Enterobacters

J Basic Microbiol, 1998, 38(4), 283 - 7
Detection of N6-methyladenine in GATC sequences of Selenomonas ruminantium; Pristas P et al.; The presence of N6-methyladenine in GATC sequences in DNA of Selenomonas ruminantium was investigated using sensitive methylation discriminating isochizomeric restriction enzymes analysis . Methylated adenine was detected in 8 out of 18 tested strains belonging to the subsp . lactilytica of S . ruminantium . No corresponding restriction activity was detected in three tested strains . No GATC methylation was detected in 3 analysed S . ruminantium subsp . ruminantium strains . Sustainable progress was achieved in the molecular biology of ruminal microorganisms in the last decade . Many different genes acting in the cell wall degradation were cloned and characterized . As practically all cloning experiments were done in Escherichia coli cells, there is a lack of data about regulation of gene(s) expression in the natural hosts . However, much better understanding of molecular genetics of ruminal bacteria is required for improving rumen functions by genetic modifications of rumen bacteria . DNA methylation is main mechanism of the control of gene expression in eukaryotes . In prokaryotes, DNA methylation influences wide variety of important cellular functions as accessibility of DNA to digestion by restriction endonucleases, control of replication initiation, transposition, phage DNA packaging, including positive and negative regulation of gene expression . Most of the DNA methyltransferases; enzymes which facilitate methylation; identified in prokaryotes are part of restriction modification systems (WILSON and MURRAY 1991 . Another class of methyltransferase are independent methylases like Dam and Dcm in Escherichia coli . Dam methylase recognizes the sequence GATC and methylates adenine at N6 position (BARRAS and MARINUS 1989) . The methylation is the only documented case of prokaryotic methylation involved in the regulation of cellular process (NOYER-WIEDNER and TRAUTNER 1993) . Screening of large number of bacteria have detected the presence of Dam methylation in cyanobacteria as well as in the group of related families of Enterobacteriaceae (which includes E . coli), Parvobacteriaceae and Vibrionaceae . Methylated GATC sequences have been found in several other bacterial species (NOYER-WIEDNER and TRAUTNER 1993), however, it could be assumed that some of these methylations are due to the presence of restriction modification systems . There is no data about the presence of Dam methylation neither in Selenomonas ruminantium nor in any other ruminal bacteria . Bacteria of S . ruminantium species are known to contain frequently restriction modification systems . Several restriction endonucleases were characterized from these bacteria (VANAT et al., 1993, PRISTAS et al . 1994, 1995) . During characterization of modification activities associated with these endonucleases we have detected the modification of adenine in GATC sequences of DNA of this species.

J Biol Chem, 1998 Nov 6, 273(45), 29497 - 505
The assembly system for the outer core portion of R1- and R4-type lipopolysaccharides of Escherichia coli . The R1 core-specific beta-glucosyltransferase provides a novel attachment site for O-polysaccharides; Heinrichs DE et al.; The major core oligosaccharide biosynthesis operons from prototype Escherichia coli strains displaying R1 and R4 lipopolysaccharide core types were polymerase chain reaction-amplified and analyzed . Comparison of deduced products of the open reading frames between the two regions indicate that all but two share total similarities of 94% or greater . Core oligosaccharide structures resulting from nonpolar insertion mutations in each gene of the core OS biosynthesis operon in the R1 strain allowed assignment of all of the glycosyltransferase enzymes required for outer core assembly . The difference between the R1 and R4 core oligosaccharides results from the specificity of the WaaV protein (a beta1, 3-glucosyltransferase) in R1 and WaaX (a beta1, 4-galactosyltransferase) in R4 . Complementation of the waaV mutant of the R1 prototype strain with the waaX gene of the R4 strain converted the core oligosaccharide from an R1- to an R4-type lipopolysaccharide core molecule . Aside from generating core oligosaccharide specificity, the unique beta-linked glucopyranosyl residue of the R1 core plays a crucial role in organization of the lipopolysaccharide . This residue provides a novel attachment site for lipid A-core-linked polysaccharides and distinguishes the R1-type LPS from existing models for enterobacterial lipopolysaccharides.

Diagn Microbiol Infect Dis, 1998 Sep, 32(1), 21 - 6
Direct bacterial identification from positive BacT/Alert blood cultures using MicroScan overnight and rapid panels; Waites KB et al.; Studies were conducted on a method of direct inoculation of MicroScan overnight and rapid panels from positive BacT/Alert blood culture bottles containing standard aerobic media to determine the correlation with inoculation of the corresponding panels with a standardized bacterial suspension obtained following subculture to agar . For Gram-negative organisms, 122 of 127 (96%) overnight panels and 85 of 118 (72%) rapid panels showed complete agreement with the standard method for species identification . Highest concordance (99%) occurred with Enterobacteriaceae inoculated directly into overnight panels . For Gram-positive organisms, 70 of 85 (82%) overnight panels and 45 of 86 (52%) rapid panels showed complete agreement . These findings suggest that direct inoculation of Gram-negative overnight MicroScan panels yields results most comparable to standard methods when Enterobacteriaceae are detected and allows reporting of results 18 to 24 h sooner . Direct inoculation of Gram-positive overnight or rapid panels and Gram-negative rapid panels from this blood culture medium did not yield acceptable identification results and is not recommended.

Diagn Microbiol Infect Dis, 1998 Sep, 32(1), 1 - 7
Reassessment of the incubation time in a controlled clinical comparison of the BacT/Alert aerobic FAN bottle and standard anaerobic bottle used aerobically for the detection of bloodstream infections; Cornish N et al.; This study assessed the minimum incubation time required to detect bloodstream infections during a controlled clinical comparison of the performance characteristics of the BacT/Alert aerobic FAN bottle and the standard anaerobic bottle used aerobically except on a selective basis . Blood was collected from adults with suspected bloodstream infections and inoculated into each bottle, which was monitored in the BacT/Alert Microbial Detection System . The anaerobic bottle was vented before incubation except when cultures were obtained from patients on the colorectal and gynecologic surgical and emergency services . Statistical analysis was limited to those culture sets in which each bottle was inoculated with > or = 8 mL of blood and bacterial growth was considered to be clinically significant . A total of 682 positive cultures from 243 patients satisfied the inclusion criteria . Significantly more isolates of Staphylococcus aureus (p < 0.001), S . epidermidis (p < 0.001), other coagulase-negative staphylococci (p < 0.001), Enterococcus spp . (p = 0.04), Escherichia coli (p = 0.03), all Enterobacteriaceae (p < 0.001), Pseudomonas aeruginosa (p = 0.001), and Candida spp . (p < 0.001) were detected by the aerobic FAN bottle . Significantly more septic episodes due to S . aureus, S . epidermidis, other coagulase-negative staphylococci, Enterobacteriaceae, P . aeruginosa, and Candida spp . were detected by the aerobic FAN bottle . Significantly more bacterial isolates were detected by the aerobic FAN whether or not antibiotics were being administered at the time of blood culture, whereas there were significantly fewer positive cultures in the vented standard anaerobic bottle when patients were receiving antimicrobial therapy than when they were not . All but 5% of positive cultures were detected within three days . Only six of the cultures requiring four or five days of incubation represented true misses, and only one of these six resulted in a change in therapy which, however, did not affect the patent's outcome.

Mol Microbiol, 1998 Oct, 30(2), 221 - 32
Molecular basis for structural diversity in the core regions of the lipopolysaccharides of Escherichia coli and Salmonella enterica; Heinrichs DE et al.; Bacterial lipopolysaccharides (LPS) are unique and complex glycolipids that provide characteristic components of the outer membranes of Gram-negative bacteria . In LPS of the Enterobacteriaceae, the core oligosaccharide links a highly conserved lipid A to the antigenic O-polysaccharide . Structural diversity in the core oligosaccharide is limited by the constraints imposed by its essential role in outer membrane stability and provides a contrast to the hypervariable O-antigen . The genetics of core oligosaccharide biosynthesis in Salmonella and Escherichia coli K-12 have served as prototypes for studies on the LPS and lipo-oligosaccharides from a growing range of bacteria . However, despite the wealth of knowledge, there remains a number of unanswered questions, and direct experimental data are not yet available to define the precise mechanism of action of many gene products . Here we present a comparative analysis of the recently completed sequences of the major core oligosaccharide biosynthesis gene clusters from the five known core types in E . coli and the Ra core type of Salmonella enterica serovar Typhimurium and discuss advances in the understanding of the related biosynthetic pathways . Differences in these clusters reflect important structural variations in the outer core oligosaccharides and provide a basis for ascribing functions to the genes in these model clusters, whereas highly conserved regions within these clusters suggest a critical and unalterable function for the inner region of the core.

Electrophoresis, 1998 Oct, 19(13), 2324 - 30
Changes in outer membrane protein profiles of bacteria after meropenem-induced postantibiotic effect studied by capillary electrophoresis; Kustos I et al.; Persistent inhibition of bacterial growth, called postantibiotic effect (PAE), after a short exposure to a new carbapenem, meropenem, was determined in different strains of the Enterobacteriaceae family . Capillary electrophoresis (CE), as well as sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were used to study the outer membrane protein (OMP) profiles before and after meropenem treatment . CE proved to be suitable for the characterization of the OMP profiles of bacteria . Significant changes in the electrophoretic patterns were observed, showing the consequential effect of meropenem on bacteria.

Electrophoresis, 1998 Oct, 19(13), 2317 - 23
Protein profile characterization of bacterial lysates by capillary electrophoresis; Kustos I et al.; A fast and reproducible method was developed to characterize cell lysates by their electrophoretic profiles using capillary electrophoresis (CE) . Characteristic and reproducible patterns were recorded for each bacterial strains when "dynamic sieving" CE, using a polymer solution in the capillary, was applied to distinguish four strains of the Enterobacteriaceae family . The electropherograms showed distinct differences when comparing them to the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) protein profiles . This is certainly a result of the differences in the separation principles and in the detection methods of the two techniques.

Mikrobiol Z, 1998 May-Jun, 60(3), 31 - 7
{The biological properties of Rahnella aquatilis strains isolated in different regions}; Pokhyl SI; Biological properties (morphological, tinctorial, cultural, biochemical, serological, genetic) of 25 Rahnella aquatilis strains, 21 of them being isolated in the territory of Ukraine and Russia, have been studied with results presented . The research data will allow specialists to isolate these microorganisms from biotic and abiotic objects of the environment and to differentiate them from other representatives of Enterobacteriaceae.

Infect Immun, 1998 Nov, 66(11), 5196 - 201
Lipoprotein release by bacteria: potential factor in bacterial pathogenesis; Zhang H et al.; Lipoprotein (LP) is a major component of the outer membrane of bacteria in the family Enterobacteriaceae . LP induces proinflammatory cytokine production in macrophages and lethal shock in LPS-responsive and -nonresponsive mice . In this study, the release of LP from growing bacteria was investigated by immuno-dot blot analysis . An immuno-dot blot assay that could detect LP at levels as low as 100 ng/ml was developed . By using this assay, significant levels of LP were detected in culture supernatants of growing Escherichia coli cells . During mid-logarithmic growth, approximately 1 to 1.5 microgram of LP per ml was detected in culture supernatants from E . coli . In contrast, these culture supernatants contained 5 to 6 microgram/ml of lipopolysaccharide (LPS) . LP release was not unique to E . coli . Salmonella typhimurium, Yersinia enterocolitica, and two pathogenic E . coli strains also released LP during in vitro growth . Treatment of bacteria with the antibiotic ceftazidime significantly enhanced LP release . Culture supernatants from 5-h cultures of E . coli were shown to induce in vitro production of interleukin-6 (IL-6) by macrophages obtained from LPS-nonresponsive C3H/HeJ mice . In contrast, culture supernatants from an E . coli LP-deletion mutant were significantly less efficient at inducing IL-6 production in C3H/HeJ macrophages . These results suggest, for the first time, that LP is released from growing bacteria and that this released LP may play an important role in the induction of cytokine production and pathologic changes associated with gram-negative bacterial infections.

Zh Mikrobiol Epidemiol Immunobiol, 1998 Jul-Aug, (4), 69 - 73
{The etiology of sporadic acute pneumonia in children}; Vishniakova LA et al.; The complex microbiological study of tracheobronchial washings and the detection of antibodies to surface components of whole bacterial cells in the indirect fluorescence test permitted the determination of the pneumococcal etiology of acute pneumonia (AP) in 134 children aged 1 month to 13 years (97.1%) . In the course of AP 13 patients (9.4%) were found to have acute infectious processes caused by Haemophilus influenzae (5 cases), different enterobacteria (4 cases), Moraxella catarrhalis (2 cases), as well acute infectious destruction of the lungs and pyopneumothorax (1 case), whose etiological factors were Staphylococcus aureus and nontyping H . influenzae strains.

Zh Mikrobiol Epidemiol Immunobiol, 1998 Jul-Aug, (4), 12 - 4
{The corrective action of antibodies in experimental intestinal dysbacteriosis}; Chkhaidze IG et al.; As shown in this work, antisera obtained after the immunization of animals with vaccines, prepared from Salmonella minnesota strain R595 (Re mutant) or Escherichia coli O14 having enterobacterial common antigen (ECA), as well as human antisera with elevated titers of antibodies to Re glycolipid or to LPS O14 (ECA), inhibited the development of experimental intestinal dysbacteriosis in white mice, induced by the administration of ampyox in large doses . The degree of the inhibiting action of the antisera was proportional to antibody titers, which was indicative of the fact that antibodies possibly played some role in the regulation of the amount of intestinal microflora.

Zh Mikrobiol Epidemiol Immunobiol, 1998 Jul-Aug, (4), 6 - 8
{The effect of the pH of the medium on induced autolysis in populations of enterobacteria}; Akaizin ES; Changes in pH in the process of the induced autolysis of salmonellae and Escherichia coli were studied . The induced autolysis of enterobacterial populations was studied in connection with the acidity values of the medium in which the process was carried out . The pH of extracellular fluid, the optical density of cell suspension, the content of total protein and amino nitrogen were analyzed . Enterobacterial populations were found to be capable of the self-regulation of the acidity of the medium in the process of induced autolysis . The study revealed that the most Intensive autolysis of bacteria took place when the process was carried out in extreme alkaline values of pH.

Adv Exp Med Biol, 1998, 443, 239 - 46
The mechanism of in vivo bacteriostasis of bovine lactoferrin; Ogata T et al.; Recently we have reported that orally administered bovine Lf(bLf) exerts bacteriostatic effects against bacterial overgrowth in the intestine of specific-pathogen-free (SPF) mice fed milk . In this animal model, the in vivo bacteriostatic effect of bLf against the proliferation of intestinal Enterobacteriaceae, the bacteria most sensitive to bLf, was independent of the iron-chelating ability of bLf . In addition various proteolytic hydrolysates of bLf (with differing antibacterial activities in vitro) showed the same bacteriostatic effect as undigested bLf . These results suggest that the mechanism of in vivo bacteriostasis of Lf differs from the in vitro mechanism reported . In SPF mice fed milk differing in concentrations of lactose, glucose and galactose, the proliferation of intestinal Enterobacteriaceae was dependent on the carbohydrate concentration in the diet . The addition of 2% bLf to the diets significantly suppressed this carbohydrate-dependent proliferation of bacteria except in the case of diets containing excess carbohydrate . In germ-free mice fed sterile milk, the addition of 2% bLf to milk resulted in a significant decrease in concentrations of lactose, glucose and galactose in the cecal contents . In an in vitro assay system using everted sacs of the small intestine of SPF mice, both bLf and its pepsin hydrolysate apparently stimulated glucose absorption . Based on these findings, we propose that the in vivo mechanism of action of ingested bLf involves the stimulation of carbohydrate absorption resulting in a bacteriostatic effect against Enterobacteriaceae in the intestine of mice fed milk.

J Clin Microbiol, 1998 Nov, 36(11), 3273 - 7
Use of the BacT/Alert blood culture system for culture of sterile body fluids other than blood; Bourbeau P et al.; Studies have demonstrated that large-volume culture methods for sterile body fluids other than blood increase recovery compared to traditional plated-medium methods . BacT/Alert is a fully automated blood culture system for detecting bacteremia and fungemia . In this study, we compared culture in BacT/Alert standard aerobic and anaerobic bottles, BacT/Alert FAN aerobic and FAN anaerobic bottles, and culture on routine media for six specimen types, i.e., continuous ambulatory peritoneal dialysate (CAPD), peritoneal, amniotic, pericardial, synovial, and pleural fluids . Specimen volumes were divided equally among the three arms of the study . A total of 1,157 specimens were tested, with 227 significant isolates recovered from 193 specimens . Recovery by method was as follows: standard bottles, 186 of 227 (82%); FAN bottles, 217 of 227 (96%); and routine culture, 184 of 227 (81%) . The FAN bottles recovered significantly more gram-positive cocci (P < 0.001), Staphylococcus aureus (P = 0.003), coagulase-negative staphylococci (P = 0.008), gram-negative bacilli (P < 0.001), Enterobacteriaceae (P = 0.005), and total organisms (P < 0.001) than the routine culture . There were no significant differences in recovery between the standard bottles and the routine culture . The FAN aerobic bottle recovered significantly more gram-positive cocci (P < 0.001), S . aureus isolates (P < 0.001), coagulase-negative staphyococci (P = 0.003), and total organisms (P < 0.001) than the standard aerobic bottle, while the FAN anaerobic bottle recovered significantly more gram-positive cocci (P < 0.001), S . aureus isolates (P < 0.001), Enterobacteriaceae (P = 0.03), and total organisms (P < 0.001) than the standard anaerobic bottle . For specific specimen types, significantly more isolates were recovered from the FAN bottles compared to the routine culture for synovial (P < 0.001) and CAPD (P = 0.004) fluids . Overall, the FAN bottles were superior in performance to both the standard bottles and the routine culture for detection of microorganisms from the types of sterile body fluids included in this study.

J Clin Microbiol, 1998 Nov, 36(11), 3266 - 72
Serratia ficaria: a misidentified or unidentified rare cause of human infections in fig tree culture zones; Anahory T et al.; Serratia ficaria, an enterobacterium involved in the fig tree ecosystem, has been isolated from human clinical samples in rare instances, and its role as a pathogen is unclear . In 7 years, we have isolated S . ficaria from seven patients; it was the only pathogen in 4 patients, including a patient with septicemia described previously and three patients with gallbladder empyemas described in the present report . From March 1995 to July 1997, the incidence of biliary infections due to S . ficaria was 0.7% . We discuss the digestive carriage of this bacterium and its epidemiology with respect to the fig tree life cycle . Since fig trees grow around the Mediterranean as well as in the United States (California, Louisiana, Hawaii), S . ficaria should be more frequently isolated . In our experience, various strains have been misidentified or unidentified by commercial systems . Incorrect identification could be an additional explanation for the paucity of reported cases . S . ficaria produces nonpigmented, lactose-negative colonies which give off a potatolike odor . This odor is the primary feature of S . ficaria and must prompt reexamination of the identifications proposed by commercial systems . We tested 42 novel strains using three commercial systems: Vitek gram-negative identification (GNI) cards and API 20E and ID 32E strips (bioMerieux, Marcy-l'Etoile, France) . The percentages of positivity that we have obtained were lower than those published previously for the following characteristics: lipase, gelatinase, DNase, and rhamnose . The best system for the recognition of S . ficaria is ID 32E, which correctly identified 27 of 42 strains . The API 20E system gave correct identifications for only two strains . S . ficaria was not present in the Vitek GNI card system database.

Am J Kidney Dis, 1998 Oct, 32(4), 623 - 8
Differing outcomes of gram-positive and gram-negative peritonitis; Troidle L et al.; Peritonitis remains the leading cause of patient dropout from continuous peritoneal dialysis (CPD) therapy . Few studies have compared patient morbidity, mortality, and outcome for patients undergoing CPD who develop gram-positive and gram-negative peritonitis . We retrospectively reviewed the charts of patients who developed either gram-positive or gram-negative peritonitis between January 1, 1993, and December 31, 1995 . Three hundred seventy-five patients who developed 415 episodes of gram-positive and gram-negative peritonitis were maintained on CPD therapy during this time period . There was no difference in age, race, and sex between patients who developed gram-positive or gram-negative peritonitis . More patients with diabetes developed gram-negative peritonitis than gram-positive peritonitis (53% v 40%, respectively; P < 0.05) . Coagulase-negative staphylococcal species accounted for 47% of all gram-positive episodes, whereas Klebsiella organisms, Escherichia coli, and Enterobacter organisms accounted for 63% of all gram-negative episodes . Significantly more patients who developed gram-positive peritonitis continued CPD therapy 2 weeks and 6 months after the onset of peritonitis than patients who developed gram-negative peritonitis (97% v 73%; P < 0.05 at 2 weeks and 81% v 58% at 6 months; P < 0.05, respectively) . Nine percent of the patients who developed gram-positive peritonitis died within 6 months after the onset of peritonitis, whereas 21% of the patients who developed gram-negative peritonitis died (P < 0.05) . Patients who developed gram-negative peritonitis were significantly more likely to require hospitalization than patients who developed gram-positive peritonitis (74% v 24%; P < 0.001) . More patients with gram-negative peritonitis required peritoneal catheter removal than patients with gram-positive peritonitis (18% v 4%; P < 0.001) . Thirty-two percent of the patients who developed gram-positive peritonitis re-developed an episode of peritonitis with the same organism compared with only 9% of the patients who developed gram-negative peritonitis . Furthermore, peritonitis recurrence with the same organism within 6 months after the initial episode was noted in 60% of the patients with peritonitis caused by Staphylococcus aureus compared with 24% of patients with peritonitis caused by other gram-positive organisms (P < 0.05) . We conclude that the outcomes of gram-positive and gram-negative peritonitis are different . When rates of peritonitis are used to predict outcome, it appears that gram-positive and gram-negative peritonitis rates need to be examined separately.

Zhonghua Yi Xue Za Zhi, 1997 May, 77(5), 332 - 5
{Changes in patterns and resistances of bacteria from 731 patients with bacteremia in 11 years}; Xin J et al.; OBJECTIVE: To study the changes in patterns and resistances of bacteria from patients with bacteremia in 11 years . METHODS: Diffusion tests were used to measure the antibiotic sensitivity of bacteria isolated from the patients with bacteremia . RESULTS: The proportion of staphylococcus epidermidis in bacteremia increased significantly . The proportion of methicillin-resistant Staphylococcus aureus (MRSA) in bacteremia caused by staphyiococcus increased markedly . Resistance of MRSA and methlcillin-sensitive staphylococcus aureus (MSSA) to penicillin, and gentamycin increased significantly . Compared 1986-1990, with 1991-1996, the resistance of S . epidermidis to penicillin, erythromycin and methicillin increased markedly, so did resistance of pseudomonas aeruginosa to carbenicillin, and piperacillin, resistance of E . coli to gentamycin and cefoperazone, resistance of klebsiella to ampicillin and carbenicillin . The resistance of enterobacteriaceae which induced beta-lactamase to the first to the third generation of cephalosporins was relatively high . CONCLUSION: The resistance of bacteria to the commonly used antibiotics was produced in various degrees.

Pathol Biol (Paris), 1998 Jan, 46(1), 67 - 72
{A three-dimensional model for in vitro study of the association of three antibiotics . Application to the activity of piperacillin, tazobactam and amikacin against five strains of enterobacteria as a function of their phenotype of beta-lactam resistance}; Duez JM et al.; We described an in vitro 3-dimensional model to study the bactericidal activity of piperacillin (P), tazobactam (T) and amikacin (A) in combination against 5 strains of enterobacteria with different resistance patterns of beta-lactam antibiotics . A synergy was defined by calculation of sigma FBCP,T,A = BCp/MBCp + BCT/MBCT + BCA/MBCA and classic sigma FBCs for each double combination . The therapeutic value of each antibiotic was estimated by comparison of its bactericidal concentrations alone and in double or triple combination.

Pathol Biol (Paris), 1998 Apr, 46(4), 261 - 7
{Multiresistant bacteria in pediatrics}; Bonacorsi S et al.; Microorganisms that are resistant to multiple antimicrobial agents are of great concern to pediatric clinicians . Children infected with antibiotic-resistant bacteria are at risk to not respond to initial therapy . Nosocomial infection of pediatric patients with multidrug-resistant organisms are similar to those found in adults especially for Staphylococcus aureus, coagulase-negative staphylococci, vancomycin resistant Enterococcus and Enterobacteriaceae resistant to third-generation cephalosporin . However on the contrary to adult patients, multidrug-resistant bacteria are found in community infections with penicillin-resistant Streptococcus pneumoniae and P . aeruginosa in CF patients.

Pathol Biol (Paris), 1998 Apr, 46(4), 235 - 43
{Enterobacteria producing extended spectrum beta-lactamases}; Lucet JC et al.; Extended-spectrum beta-lactamases (ESBL) were first observed in 1983 . Since then, the number and variety of ESBLs have increased rapidly, particularly in France, and their distribution is now worldwide . The number of ESBLs has now reached more than 30, some of them spreading largely in several countries, such as SHV-4 in France . Intensive care units were first involved . Patients from nursing homes may recirculate ESBLs into acute care units . ESBL clinical epidemiology does not differ from other enterobacteriaceae . Digestive tract is the main reservoir, hands are the route of transmission . Infection develops in about 50% of colonized patients, more than one-half being urinary tract infections . Risk factors for colonization or infection are length of exposure to an epidemic strain and frequency of health-care-worker contact . Strategies for containing spreading of ESBL-producing strains include use of barrier precautions for carriers . Judicious use of antimicrobial agents is also important, by decreasing antibiotic selective pressure.

Pathol Biol (Paris), 1998 Apr, 46(4), 217 - 26
{Surveillance of multiresistant bacteria: justification, role of the laboratory, indicators, and recent French data}; Marty L et al.; In France, several organizations have given priority status to programs aimed at controlling outbreaks of nosocomial infections due to multiresistant bacteria (MRB), most notably methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBLE), thus recognizing the widespread distribution and marked pathogenic potential of MRB . To evaluate the impact of preventive measures, surveillance systems have been set up by bacteriology laboratories . These systems rest on a number of indicators: (1) the percentage of strains of a given bacterial species recovered from diagnostic specimens that were multiresistant; (2) the number of new patients (cases) with recovery of a MRB strain from at least one diagnostic specimen (or at least one screening specimen); (3) the incidence, or incidence density, of cases per 1000 hospital days or 100 admissions; (4) the distinction between cases acquired in and transported to the hospital or department . Studies conducted in France between 1990 and 1995 found that the percentage of Klebsiella pneumoniae that were multiresistant was around 20% overall and 25 to 35% among nosocomial strains, and that the prevalence and incidence of cases were about 0.1 to 0.3 per 100 admissions . The proportion of S . aureus strains exhibiting resistance to methicillin was 35 to 40% overall and 50% among nosocomial strains, and the prevalence and incidence of cases ranged from 0.5 to 1 per 100 admissions.

Pathol Biol (Paris), 1998 Jun, 46(6), 403 - 7
{Epidemiology of hospital bacteremias in eastern France . Eastern CCLIN Network}; Bussy Malgrange V et al.; Bacteremia occurs frequently among critically ill patients . The aim of this study carried out in Eastern France was to describe the epidemiology of nosocomial bacteremia and to assess the methicillin-resistance of Staphylococcus aureus (SA) . Data were collected during a 4 months prospective survey (09/96-12/96) carried out among 44 hospitals . We counted 2633 episodes of bacteremia classified as contamination (684), nosocomial bacteremia (970) and community bacteremia (979) . Incidence rate of nosocomial bacteremia was 30.7 per 100 beds in the intensive care units . When documented, the origin of the nosocomial bacteremia was the most often catheter blood related infection or urinary tract infection . Gram positif cocci were predominant among nosocomial bacteremia (53.8%) . Among Gram negative bacteria (enterobacteria) (31.6%), Escherichia coli was the most frequently isolated . SA was methicillin-resistant in 18.3% of community bacteremia and in 26.5% of nosocomial bacteremia . Coagulase negative Staphylococcus were methicillin-resistant in 25.4% of community bacteremia and in 60.1% of nosocomial bacteremia . Measures to prevent catheter blood related infections and urinary tract infections may be started.

Presse Med, 1998 May 2-9, 27(17), 804 - 5
{Enterobacter aerogenes pneumopathy treated by a cefepime-sulbactam-gentamicin combination}; Mardrus P et al.; BACKGROUND: Enterobacter aerogenes is the fifth most frequent pathogen causing nosocomial infections . Several strains have developed multiple resistance by over-production of a natural cephalosporinase and by the presence of wide-spectrum betalactamases . CASE REPORT: A patient with chronic respiratory failure developed Enterobacter aerogenes pneumonia while under mechanical ventilation . The infection was successfully treated with a cefepime, sulbactam, gentamycin combination . DISCUSSION: Choosing the optimum antibiotic therapy is a difficult task in many nosocomial infections . In certain cases, combining a betalactamase inhibitor with the appropriate antibiotic can improve bactericidal activity and provide successful cure.

Presse Med, 1998 Jun 27, 27(23), 1140 - 2
{Intracranial hypertension in a newborn treated with quinolone}; Bedu A et al.; BACKGROUND: Fluoroquinolones have not received administrative authorization for use in children, but because of multiresistant pathogens in neonatal intensive care, floroquinolones may be the only alternative . CASE REPORT: A premature infant exclusively nourished by parenteral nutrition developed enterobacteria sepsis . Ceftazidine was given initially but resistance led to the prescription of fluoroquinolone . Signs of intracranial hypertension developed 3 days after onset of fluoroquinolone treatment and regressed 48 hours after its withdrawal . DISCUSSION: The main potential adverse effects with fluoroquinone in the newborn are arthropathy, photosensitivity, discoloration of the teeth and neurological disorders . Intracranial hypertension is a known complication of nalidixic acid both in adults and children, but to our knowledge has not been previously with floroquinolone in the newborn.

J Med Chem, 1998 Oct 8, 41(21), 3961 - 71
Structure-based design of beta-lactamase inhibitors . 1 . Synthesis and evaluation of bridged monobactams; Heinze-Krauss I et al.; Bridged monobactams are novel, potent, mechanism-based inhibitors of class C beta-lactamases, designed using X-ray crystal structures of the enzymes . They stabilize the acyl-enzyme intermediate by blocking access of water to the enzyme-inhibitor ester bond . Bridged monobactams are selective class C beta-lactamase inhibitors, with half-inhibition constants as low as 10 nM, and are less effective against class A and class B enzymes (half-inhibition constants > 100 microM) because of the different hydrolysis mechanisms in these classes of beta-lactamases . The stability of the acyl-enzyme complexes formed with class C beta-lactamases (half-lives up to 2 days were observed) enabled determination of their crystal structures . The conformation of the inhibitor moiety was close to that predicted by molecular modeling, confirming a simple reaction mechanism, unlike those of known beta-lactamase inhibitors such as clavulanic acid and penam sulfones, which involve secondary rearrangements . Synergy between the bridged monobactams and beta-lactamase-labile antibiotics could be observed when such combinations were tested against strains of Enterobacteriaceae that produce large amounts of class C beta-lactamases . The minimal inhibitory concentration of the antibiotic of more than 64 mg/L could be decreased to 0.25 mg/L in a 1:4 combination with the inhibitor.

Leukemia, 1998 Oct, 12(10), 1627 - 9
Decreasing antibiotic resistance of Enterobacteriaceae by introducing a new antibiotic combination therapy for neutropenic fever patients; Mebis J et al.; Prompt empiric antibiotic therapy is of critical importance for patients with neutropenic fever . However, a major concern with important clinical consequences is the emergence of bacterial resistance to antibiotics . After using ceftazidime with a glycopeptide as initial empiric therapy for neutropenic fever, we were confronted with a 75% reduced susceptibility rate to ceftazidime of inducible Enterobacteriaceae collected in 1994 . The initial empiric therapy was therefore replaced in May 1995 by a combination of cefepime with amikacin, with addition of a glycopeptide after 48 h if necessary . After this change, we observed a significant decrease in reduced susceptibility of inducible Enterobacteriaceae, not only to ceftazidime, but also to amikacin, cotrimoxazole and ciprofloxacin . There was also a decrease in reduced susceptibility of non-inducible Enterobacteriaceae, such as Klebsiella spp, to ceftazidime . The reduction of resistance may be related at least in part to the combined use of cefepime together with an aminoglycoside . This study shows that it is possible to reverse bacterial resistance by modifying the antibiotic regimen used.

J Pediatr Surg, 1998 Sep, 33(9), 1338 - 40
Elective delayed reduction and no anesthesia: 'minimal intervention management' for gastrochisis; Bianchi A et al.; PURPOSE: In a pilot study of 14 children, born when the authors were on a 1:5 "on take" for neonatal referrals, a policy evolved of elective delayed midgut reduction without anaesthesia or sedation in the incubator on the neonatal surgical unit . There was no other form of selection, and it was fortunate that the authors did not encountered any adverse criteria in this small series . METHODS: Bowel reduction, which was pain free, was undertaken conventionally with the same attention and with no greater difficulty than under general anesthesia . Delaying midgut reduction for more than 4 hours led to more stable cardiovascular, respiratory, and renal parameters . Moderate lower limb congestion cleared rapidly . RESULTS: At the end of the procedure, all children were conscious, and 12 were alert and indistinguishable from normal babies . A mild periumbilical infection developed in two patients . Eleven of the 12 surviving children established enteral nutrition within 11 to 32 days, eight within 18 days . Another child with ileal atresia and bowel dilatation required bowel tailoring and lengthening (LILT) to allow enteral nutrition . All are physically and developmentally normal, and none has required umbilical herniorrhaphy or umbilicoplasty . All except one have a "scarless" abdomen and an aesthetically normal umbilicus . In marked comparison, two children immediately and obviously were unwell with abdominal pain, tachycardia, and metabolic acidosis . Abdominal wall cellulitis rapidly developed in both . At laparotomy one had a midgut volvulus and died at 22 months of short bowel syndrome (SBS) and the other with a perforated segmental ileal atresia died at 7 months of Enterobacter cloacae septicaemia . CONCLUSIONS: Our small study suggests that delayed midgut reduction without anaesthesia appears safe, carrying no additional morbidity or mortality . It helps avoid anaesthesia, muscle relaxants, and ventilation and has obvious resource benefits . The conscious child is a safety asset, and any postreduction deviation from a "normal, well-perfused, comfortable, and painfree" child is an indication for urgent laparotomy . This "minimal intervention management," when applicable, has become our preferred first option for children with gastroschisis . Further extension of this study will determine those not eligible for this technique and establish "exclusion criteria."

Res Microbiol, 1997 Jul-Aug, 148(6), 475 - 84
Relationship between the physiology of Enterobacter agglomerans CNCM 1210 grown anaerobically on glycerol and the culture conditions; Barbirato F et al.; In a preliminary study, levels of activity of enzymes involved in anaerobic glycerol catabolism by Enterobacter agglomerans grown in batch cultures regulated in a pH range of 6.5-8.0 were monitored . That study showed that activities of key enzymes of the downstream metabolism of glycerol--glyceradehyde-3-phosphate dehydrogenase (GAP-DH), lactate dehydrogenase and pyruvate formate lyase--were strongly dependent on the culture pH . To investigate the influence of pH on the physiology of the strain, E . agglomerans was grown anaerobically in a continuous culture supplied with glycerol as the sole carbon source and regulated at pH 8 . A complete biochemical analysis was performed and was compared with that previously described for the continuous culture regulated at pH 7 . A limitation of the glycolytic flux at the level of GAP-DH was demonstrated at high dilution rate, resulting in an overflow metabolism through the 1,3-propanediol formation pathway . Increasing the specific rate of glycerol consumption also resulted in enhanced lactate production due to limitation by the pyruvate decarboxylation step . Finally, changing the culture pH significantly modified the enzymatic profile of E . agglomerans, and it enabled the stability of the culture to be increased by preventing the accumulation in the fermentation broth of 3-hydroxypropionaldehyde, an inhibitory metabolite, when the glycerol supply was suddenly increased.

Res Microbiol, 1997 Feb, 148(2), 133 - 43
Molecular characterization of a 17-kDa outer-membrane protein from Klebsiella pneumoniae; Climent N et al.; A cosmid-based genomic library of Klebsiella pneumoniae 52145 (O1:K2) was introduced into Escherichia coli, and clones were screened for the bacteriocin 28b resistance phenotype . One clone was found which conferred partial resistance to bacteriocin 28b . By using Tn5tac1 insertions, it was shown that this phenotype was due to the expression, in E . coli, of an outer-membrane protein (OMP) with an apparent molecular mass of 17 kDa (OmpK17) . The DNA region defined by insertion mutagenesis was sequenced and found to contain an ORF of 510 bp . The deduced amino acid sequence has 170 residues with a theoretical molecular mass of 18.4 kDa . The protein contains an N-terminal signal sequence of 24 amino acid residues . When compared with other enterobacterial OMPs, OmpK17 most closely resembles members of a family of small OMPs of Enterobacteriaceae the known functions of which appear to be related to virulence . Immunoblotting experiments showed that OmpK17 is also present in various K . pneumoniae strains belonging to different O and K serotypes.

Acta Crystallogr D Biol Crystallogr, 1998 Jul 1, 54 ( Pt 4), 675 - 7
Crystallization and preliminary diffraction studies of pentaerythritol tetranitrate reductase from Enterobacter cloacae PB2; Moody PC et al.; Pentaerythritol tetranitrate (PETN) reductase of Enterobacter cloacae PB2, a flavoprotein involved in the biodegradation of the explosive PETN, ethylene glycol dinitrate (EGDN) and glycerol trinitrate (GTN), was purified from an overexpressing strain of E . coli and crystallized at 293 K using the sitting-drop vapour-diffusion method . Diffraction data can be seen at 1.8 A . The primitive orthorhombic cell has a monomer in the asymmetric unit . Preliminary molecular-replacement calculations have been performed using a search model based on Old Yellow enzyme.

Int J Food Microbiol, 1998 Aug 18, 43(1-2), 123 - 7
A novel, selective synthetic acetamide containing culture medium for isolating Pseudomonas aeruginosa from milk; Szita G et al.; A selective synthetic medium has been developed both in liquid (Z-broth) and solid (Z-agar) forms for selective isolation of Pseudomonas aeruginosa from foods . The simple, easy to prepare peptone-free synthetic medium contained acetamide that is metabolized to ammonia and acetic acid providing nitrogen and carbon supply . The medium contained no inhibitors . Selectivity of the liquid medium was tested by inoculation of pure cultures of different bacteria belonging to the groups Bacillus, Pseudomonas, Enterobacteriaceae and Staphylococcus . It was found that the selectivity of the medium was complete for the examined range of bacteria . However, a similar result was obtained when nitrofurantoin broth was used . Applicability of the synthetic agar medium was also tested by a nation-wide inter-laboratory test using two milk samples containing 10(3)/ml (sample I) and 10(5)/ml (sample II) Pseudomonas aeruginosa . According to this test, no microbiologically relevant differences were found between the results obtained by Z-agar and cetrimide-agar a frequently used selective agar in case of sample II . However, a relevant and statistically significant difference was found in the results of sample I in favour of the Z-agar, that could indicate the presence of a low number of bacteria . Concerning repeatability and reproducibility, Z-agar proved to be superior to cetrimide agar.

Appl Environ Microbiol, 1998 Oct, 64(10), 3818 - 23
Genetic characterization of pseudomonas syringae pv . syringae strains from stone fruits in california
Little EL, Bostock RM, Kirkpatrick BC.
Strains of Pseudomonas syringae pv . syringae were isolated from healthy and diseased stone fruit tissues sampled from 43 orchard sites in California in 1995 and 1996 . These strains, together with P . syringae strains from other hosts and pathovars, were tested for pathogenicity and the presence of the syrB and syrC genes and were genetically characterized by using enterobacterial repetitive intergenic consensus (ERIC) primers and PCR . All 89 strains of P . syringae pv . syringae tested were moderately to highly pathogenic on Lovell peach seedlings regardless of the host of origin, while strains of other pathovars exhibited low or no pathogenicity . The 19 strains of P . syringae pv . syringae examined by restriction fragment length polymorphism analysis contained the syrB and syrC genes, whereas no hybridization occurred with 4 strains of other P . syringae pathovars . The P . syringae pv . syringae strains from stone fruit, except for a strain from New Zealand, generated ERIC genomic fingerprints which shared four fragments of similar mobility . Of the P . syringae pv . syringae strains tested from other hosts, only strains from rose, kiwi, and pear generated genomic fingerprints that had the same four fragments as the stone fruit strains . Analysis of the ERIC fingerprints from P . syringae pv . syringae strains showed that the strains isolated from stone fruits formed a distinct cluster separate from most of the strains isolated from other hosts . These results provide evidence of host specialization within the diverse pathovar P . syringae pv . syringae.

Appl Environ Microbiol, 1998 Oct, 64(10), 3740 - 7
Colonization of wheat roots by an exopolysaccharide-producing pantoea agglomerans strain and its effect on rhizosphere soil aggregation
Amellal N, Burtin G, Bartoli F, Heulin T.
The effect of bacterial secretion of an exopolysaccharide (EPS) on rhizosphere soil physical properties was investigated by inoculating strain NAS206, which was isolated from the rhizosphere of wheat (Triticum durum L.) growing in a Moroccan vertisol and was identified as Pantoea aglomerans . Phenotypic identification of this strain with the Biotype-100 system was confirmed by amplified ribosomal DNA restriction analysis . After inoculation of wheat seedlings with strain NAS206, colonization increased at the rhizoplane and in root-adhering soil (RAS) but not in bulk soil . Colonization further increased under relatively dry conditions (20% soil water content; matric potential, -0.55 MPa) . By means of genetic fingerprinting using enterobacterial repetitive intergenic consensus PCR, we were able to verify that colonies counted as strain NAS206 on agar plates descended from inoculated strain NAS206 . The intense colonization of the wheat rhizosphere by these EPS-producing bacteria was associated with significant soil aggregation, as shown by increased ratios of RAS dry mass to root tissue (RT) dry mass (RAS/RT) and the improved water stability of adhering soil aggregates . The maximum effect of strain NAS206 on both the RAS/RT ratio and aggregate stability was measured at 24% average soil water content (matric potential, -0.20 MPa) . Inoculated strain NAS206 improved RAS macroporosity (pore diameter, 10 to 30 &mgr;m) compared to the noninoculated control, particularly when the soil was nearly water saturated (matric potential, -0.05 MPa) . Our results suggest that P . agglomerans NAS206 can play an important role in the regulation of the water content (excess or deficit) of the rhizosphere of wheat by improving soil aggregation.

Appl Environ Microbiol, 1998 Oct, 64(10), 3824 - 30
Phenotypic and phylogenetic characterization of ruminal tannin-tolerant bacteria; Nelson KE et al.; The 16S rRNA sequences and selected phenotypic characteristics were determined for six recently isolated bacteria that can tolerate high levels of hydrolyzable and condensed tannins . Bacteria were isolated from the ruminal contents of animals in different geographic locations, including Sardinian sheep (Ovis aries), Honduran and Colombian goats (Capra hircus), white-tail deer (Odocoileus virginianus) from upstate New York, and Rocky Mountain elk (Cervus elaphus nelsoni) from Oregon . Nearly complete sequences of the small-subunit rRNA genes, which were obtained by PCR amplification, cloning, and sequencing, were used for phylogenetic characterization . Comparisons of the 16S rRNA of the six isolates showed that four of the isolates were members of the genus Streptococcus and were most closely related to ruminal strains of Streptococcus bovis and the recently described organism Streptococcus gallolyticus . One of the other isolates, a gram-positive rod, clustered with the clostridia in the low-G+C-content group of gram-positive bacteria . The sixth isolate, a gram-negative rod, was a member of the family Enterobacteriaceae in the gamma subdivision of the class Proteobacteria . None of the 16S rRNA sequences of the tannin-tolerant bacteria examined was identical to the sequence of any previously described microorganism or to the sequence of any of the other organisms examined in this study . Three phylogenetically distinct groups of ruminal bacteria were isolated from four species of ruminants in Europe, North America, and South America . The presence of tannin-tolerant bacteria is not restricted by climate, geography, or host animal, although attempts to isolate tannin-tolerant bacteria from cows on low-tannin diets failed.

Intensive Care Med, 1998 Aug, 24(8), 839 - 44
In vitro activity of fleroxacin against multiresistant gram-negative bacilli isolated from patients with nosocomial infections; Araque M et al.; In order to evaluate the in vitro activity of fleroxacin against nosocomial gram-negative organisms, 263 multiresistant gram-negative bacilli (203 Enterobacteriaceae and 60 non-fermenting gram-negative bacilli) were isolated from adult patients with nosocomial infections . The different patterns of resistance to eight different antimicrobial agents (ampicillin, carbenicillin, piperacillin, cephalothin, cefamandole, ceftazidime, gentamicin and amikacin) were determined by minimum inhibitory concentration (MIC), using the agar dilution method . The most prevalent multiresistant species isolated were Klebsiella pneumoniae (28.9%), Escherichia coli (24%) and Pseudomonas aeruginosa (12.2%) . All these bacterial strains showed three to five resistance patterns to at least three different antibiotics . Resistance to ceftazidime was observed in at least one of the resistance patterns of isolated bacteria . The activity of fleroxacin against multiresistant enteric bacteria was excellent; these strains showed a susceptibility of 79-100% . The susceptibility of P . aeruginosa to antipseudomonal agents was low; however, the activity of fleroxacin against these strains was higher than 60% (MIC < or = 2 microg/ ml), broadly comparable with ciprofloxacin . The resistance to fluoroquinolones detected in this study was no cause for alarm (3%) . Consequently, fleroxacin maintains a remarkable activity against Enterobacteriaceae and remains highly active against other gram-negative bacilli . Nevertheless, actions directed at preventing or limiting resistance will be crucial to maintain the viability of fluoroquinolones as important therapeutic agents.

Antimicrob Agents Chemother, 1998 Oct, 42(10), 2557 - 63
Characterization of In40 of Enterobacter aerogenes BM2688, a class 1 integron with two new gene cassettes, cmlA2 and qacF; Ploy MC et al.; Enterobacter aerogenes BM2688, which is resistant to multiple antibiotics, and its aminoglycoside-susceptible derivative BM2688-1 were isolated from the same clinical sample . Strain BM2688 harbored plasmid pIP833, which carries a class 1 integron, In40, containing (in addition to qacEDelta1 and sul1, which are characteristic of class 1 integrons) four gene cassettes: aac(6')-Ib, qacF, cmlA2, and oxa-9 . The cmlA2 gene had 83.7% identity with the previously described nonenzymatic chloramphenicol resistance cmlA1 gene . The qacF gene conferred resistance to quaternary ammonium compounds and displayed a high degree of similarity with qacE (67.8% identity) which, however, has been found as part of a cassette with a very different 59-base element . The oxa-9 gene was not expressed due to a lack of promoter sequences . Study of the antibiotic-susceptible derivative BM2688-1 indicated that a 3,148-bp deletion between the 3' end of the aac(6')-Ib gene and the 3' conserved segment of In40 was responsible for the loss of resistance . The occurrence of this DNA rearrangement, which did not involve homologous sequences, suggests that the In40 integrase could promote recombination at secondary sites.

Chemotherapy, 1998 Nov-Dec, 44(6), 377 - 84
Comparative activity of piperacillin/tazobactam against clinical isolates of extended-spectrum beta-lactamase-producing Enterobacteriaceae; Pagani L et al.; beta-Lactam resistance on the part of the Enterobacteriaceae causes serious therapeutic problems in our institutions due to their production of extended-spectrum beta-lactamases (ESbetaLs) . We studied the in vitro activity of beta-lactam/beta-lactamase inhibitor combinations and third-generation cephalosporins and monobactams against 71 clinically relevant Enterobacteriaceae which produced TEM- and SHV-derivative ESbetaLs . Of the single drugs and combinations tested, piperacillin/tazobactam proved to be the most effective . Piperacillin/tazobactam was highly active against Proteus mirabilis, with minimum inhibitory concentrations (MICs) ranging from 0.125 to 16 microg/ml; Escherichia coli (MICs from 2 to 16 microg/ml) and Serratia marcescens (MICs from 4 to 8 microg/ml), while its activity against Klebsiella pneumoniae ESbetaL producers turned out to be closely related to the type and the amount of enzyme produced, the MIC ranging from 1 to 128 microg/ml . The antibacterial activity of piperacillin/tazobactam was stronger than that of ticarcillin/clavulanate, ceftriaxone, cefotaxime, ceftazidime and aztreonam, and the combination shared favorable in vitro activity properties against the ESbetaL producers with imipenem which, however, should be kept as reserve product.

J Clin Pharm Ther, 1998 Feb, 23(1), 11 - 7
Cefepime--assessment of its need at a tertiary care center; Harbarth S et al.; OBJECTIVE: To assess the need and possible indications for a fourth-generation cephalosporin (cefepime) . METHOD: A cohort study was carried out over a 17-month period in a 1500-bed Swiss university hospital . RESULTS: In 256 (22.6%) of the 1135 patients followed consecutively by our Infectious Diseases Division, cefepime could have been chosen as an alternative to other broad-spectrum antibiotics, including imipenem/cilastatin (n=94), ciprofloxacine (n=52) and ceftazidime (n=49) . Considering the low price-strategy of the pharmaceutical company promoting this drug in Switzerland, there would have been considerable cost savings for the hospital pharmacy if cefepime had been used as first-line treatment in these occasions . Nevertheless, we could not observe any potential advantage of cefepime compared to already introduced broad-spectrum antibiotics, except that cefepime was effective against infections caused by Enterobacter spp . resistant to ceftazidime . CONCLUSION: We conclude that fourth-generation cephalosporins such as cefepime may be introduced into large hospitals only after careful assessment of their potential benefits and that consultation by an Infectious Diseases Division is useful when evaluating the need for new broad-spectrum antibiotics in the hospital setting.

Rev Assoc Med Bras, 1998 Jul-Sep, 44(3), 196 - 200
{Increase in the frequency of norfloxacin and ciprofloxacin resistance of bacteria isolated from urine culture}; Lopes AA et al.; OBJECTIVE: To assess time trends in the frequency of norfloxacin and ciprofloxacin resistance of bacteria isolated from urine culture . METHODS: Results of all urine cultures with a bacterial growth of at least 10(5) colony-forming units per milliliter, performed at the Renal Service of the Federal University of Bahia, Brazil, from 1983 to 1994 were analyzed . The bacteria considered for this analysis were those most often isolated: Escherichia coli (n = 668), Klebsiella spp . (n = 286), Staphylococcus spp . (n = 186), Proteus spp . (n = 135) and Enterobacter spp . (n = 129) . RESULTS: The frequencies of norfloxacin resistance for the periods 1983-1986, 1987-1990 and 1991-1994 were 3.2%, 5.9% and 9.1%, respectively (p-value < 0.05) . The most pronounced increases in the frequencies of norfloxacin-resistance were observed for Klebsiella spp . and Enterobacter spp . The frequency of ciprofloxacin resistance was 7.4% in the period 1985-1989 and 16.5% in the period 1990-1994 (p-value < 0.05) . This time trend in ciprofloxacin resistance was more striking for Enterobacter spp . and Staphylococcus spp . CONCLUSION: The results show a gradual increase in the frequency of norfloxacin and ciprofloxacin resistance of the bacteria most commonly isolated from urine cultures . The influence of previous treatment with quinolones and characteristics of the infecting bacteria on these findings are important questions to to be addressed in future investigations.

J Appl Microbiol, 1998 Sep, 85(3), 554 - 60
Development and use of 16S rRNA gene targeted PCR primers for the identification of Escherichia coli cells in water; Tsen HY et al.; The primary sequences of the V3 and V6 regions of the 16S rRNA gene of pathogenic and non-pathogenic strains of Escherichia coli were determined and compared with those obtained for a number of reference strains which belong to the family Enterobacteriaceae . Three oligonucleotide primers 16E1, 16E2 and 16E3 were designed and used in the polymerase chain reaction to identify specifically all E . coli isolates . When 16E1, 16E2 and 16E3 were used as primers for the identification of E . coli cells present in tap, underground and pond waters, as low as 1 cfu 100 ml-1 of water could be detected if an 8 h pre-culture step was performed prior to the PCR reaction.

J Hosp Infect, 1998 Aug, 39(4), 323 - 9
Role of antimicrobial-impregnated polymer and Teflon in the prevention of biliary stent blockage; Rees EN et al.; Biliary stent blockage and microbial colonization is a common complication associated with polyurethane stents used for the relief of bile-duct obstruction caused by benign or malignant disease . In an attempt to overcome this problem the application of a 'Teflon' (polytetrafluoroethylene) stent and an antimicrobial benzalkonium chloride (BZC) impregnated polymer were investigated . The effects of these materials on microbial colonization were compared to a polyurethane stent in vitro in broth or bile . The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of BZC for three commonly isolated biliary stent pathogens, Staphylococcus epidermidis, Enterococcus faecium and Enterobacter cloacae were also determined . All the isolates were sensitive to BZC . The growth kinetics of the three organisms in broth and in human pooled bile were similar . Adherence to the BZC impregnated polymer was significantly reduced as compared to the polyurethane and Teflon stents (P < 0.05) in nutrient broth . In bile, fewer organisms attached to the Teflon as compared with the polyurethane stent (P < 0.05) for all organisms . For two of the three test organisms there was less bacterial adherence to the Teflon than to the BZC impregnated polymer . The Teflon and antimicrobial stent materials studied may prevent biliary stent blockage resulting from microbial colonization.

Biochim Biophys Acta, 1998 Sep 8, 1387(1-2), 395 - 405
Steady-state kinetic mechanism, stereospecificity, substrate and inhibitor specificity of Enterobacter cloacae nitroreductase; Koder RL et al.; Enterobacter cloacae nitroreductase (NR) is a flavoprotein which catalyzes the pyridine nucleotide-dependent reduction of nitroaromatics . Initial velocity and inhibition studies have been performed which establish unambiguously a ping-pong kinetic mechanism . NADH oxidation proceeds stereospecifically with the transfer of the pro-R hydrogen to the enzyme and the amide moiety of the nicotinamide appears to be the principal mediator of the interaction between NR and NADH . 2,4-Dinitrotoluene is the most efficient oxidizing substrate examined, with a kcat/KM an order of magnitude higher than those of p-nitrobenzoate, FMN, FAD or riboflavin . Dicoumarol is a potent inhibitor competitive vs . NADH with a Ki of 62 nM . Several compounds containing a carboxyl group are also competitive inhibitors vs . NADH . Yonetani-Theorell analysis of dicoumarol and acetate inhibition indicates that their binding is mutually exclusive, which suggests that the two inhibitors bind to the same site on the enzyme . NAD+ does not exhibit product inhibition and in the absence of an electron acceptor, no isotope exchange between NADH and 32P-NAD+ could be detected . NR catalyzes the 4-electron reduction of nitrobenzene to hydroxylaminobenzene with no optically detectable net formation of the putative two-electron intermediate nitrosobenzene.

Mol Gen Genet, 1998 Aug, 259(2), 172 - 8
The gene for indole-3-acetyl-L-aspartic acid hydrolase from Enterobacter agglomerans: molecular cloning, nucleotide sequence, and expression in Escherichia coli; Chou JC et al.; A 5.5-kb DNA fragment containing the indole-3-acetyl-aspartic acid (IAA-asp) hydrolase gene (iaaspH) was isolated from Enterobacter agglomerans strain GK12 using a hybridization probe based on the N-terminal amino acid sequence of the protein . The DNA sequence of a 2.4-kb region of this fragment was determined and revealed a 1311-nucleotide ORF large enough to encode the 45-kDa IAA-asp hydrolase . A 1.5-kb DNA fragment containing iaaspH was subcloned into the Escherichia coli expression plasmid pTTQ8 to yield plasmid pJCC2 . Extracts of IPTG-induced E . coli cultures containing the pJCC2 recombinant plasmid showed IAA-asp hydrolase levels 5 to 10-fold higher than those in E . agglomerans extracts . Homology searches revealed that the IAA-asp hydrolase was similar to a variety of amidohydrolases . In addition, IAA-asp hydrolase showed 70% sequence identity to a putative thermostable carboxypeptidase of E . coli.

FEBS Lett, 1998 Aug 21, 433(3), 233 - 6
The Ecl18kI restriction-modification system: cloning, expression, properties of the purified enzymes; Denjmukhametov MM et al.; Ecl18kI is a type II restriction-modification system isolated from Enterobacter cloaceae 18kI strain . Genes encoding Ecl18kI methyltransferase (M.Ecl18kI) and Ecl18kI restriction endonuclease (R.Ecl18kI) have been cloned and expressed in Escherichia coli . These enzymes recognize the 5'.../CCNGG...3' sequence in DNA; M.Ecl18kI methylates the C5 carbon atom of the inner dC residue and R.Ecl18kI cuts DNA as shown by the arrow . The restriction endonuclease and the methyltransferase were purified from E . coli B834 {p18Ap1} cells to near homogeneity . The restriction endonuclease is present in the solution as a tetramer, while the methyltransferase is a monomer . The interactions of M.Ecl18kI and R.Ecl18kI with 1,2-dideoxy-D-ribofuranose containing DNA duplexes were investigated . The target base flipping-out mechanism is applicable in the case of M.Ecl18kI . Correct cleavage of the abasic substrates by R.Ecl18kI is accompanied by non-canonical hydrolysis of the modified strand.

APMIS, 1998 Aug, 106(8), 818 - 24
An epitope shared by enterobacterial and neisserial porin proteins; Henriksen AZ et al.; A murine monoclonal antibody (MAb F9-16) raised against a porin protein epitope called Po I of an E . coli 055 strain showed broad cross-reactivity with bacteria within the Enterobacteriaceae, and also recognized neisseriae and moraxellae . In an immunodot assay, the antibody was bound by 32/33 strains of neisseriae and moraxellae after SDS treatment of the bacteria . Testing intact bacteria, 11/33 isolates showed definite MAb binding, including serogroup A and B meningococci . In Western blotting, the anti-Po I MAb targeted the gonococcal porin proteins PIA and PIB, and class 1, class 2, and class 3 porins of meningococci . The MAb showed no reactivity against decapeptides which corresponded to the whole length of a meningococcal class 1 porin protein of the subtype P1, 7, 16 . These findings accord with the inference that enterobacterial, neisserial and moraxellae porin proteins share an epitope (Po I) which is determined by the three-dimensional rather than by the primary structure of the proteins and that this epitope is shielded in most isolates but surface-exposed in some isolates, including some strains of meningococci . Since Po I is broadly distributed among commensal and pathogenic bacteria and has demonstrated immunogenicity in humans, this epitope may play a role in elicitation of "normal" antibodies with immunoprotective activity.

Rev Argent Microbiol, 1998 Apr-Jun, 30(2), 84 - 92
{Agglutination of hen egg-yolk immunoglobulins (IgY) against Salmonella enterica, serovar enteritidis}; Terzolo HR et al.; Two groups of 6 laying hens were used to produce IgY . In the vaccinated group (V), hens were injected by intramuscular route with two doses of a Salmonella enterica serovar Enteritidis bacterin at 20-day interval . In the control group (T) hens remained unvaccinated . Four IgY extractions were performed on the egg production of both groups . The first two extractions were carried out using the yolks obtained from the eggs produced during the 4th and 5th post-vaccination week (extracts 1V and 1T) and the other two using the ones from the 6th, 7th and 8th week (2V and 2T) . Starting from the extracts 1V and 1T other products were obtained by freezing-thawing (1V-A and 1T-A) and simple (1V-B and 1T-B) or double (1V-C and 1T-C) flow capillary dialysis concentration . All these products were compared using an ELISA test specific for the detection of chicken antibodies against flagellar antigens of S . Enteritidis . In this test, V extracts were positive whereas T extracts were negative . The extract 1V was more positive than the extract 2V . The extract 1V-C was the most positive and was therefore selected to be used as an antiserum in the agglutination tests . This extract contained 1.9 g/dl of total proteins, 0.028 g/dl of triglycerides and 0.012 g/dl of cholesterol and showed an electrophoretic pattern characteristic of IgY . The 1T-C extract was used as a negative control in the agglutination tests . Slide somatic and tube flagellar agglutination tests were simultaneously carried out using both IgY extracts and a standard rabbit anti-Salmonella (IgG) sera . Overall 367 strains from the Enterobacteriaceae family were tested together with two other strains belonging to the Vibrionaceae family . The 1V-C extract specifically agglutinated S . Enteritidis strains in the same way as the rabbit sera . This extract also agglutinated other Salmonella strains antigenically related to S . Enteritidis . Salmonella which did not share somatic or flagellar antigens with S . Enteritidis, other different species of the Enterobacteriaceae family and the two strains of the Vibrionaceae family were all negative . None of the strains tested was agglutinated by the 1T-C extract . This paper show that it is possible to use specific IgY to identify S . enterica serovars . The more extended use of IgY for diagnostic purposes may be a convenient way to complement the current use of mammal polyclonal antibodies.

Orig Life Evol Biosph, 1998 Oct, 28(4-6), 555 - 70
Evolution of the structure and chromosomal distribution of histidine biosynthetic genes; Fani R et al.; A database of more than 100 histidine biosynthetic genes from different organisms belonging to the three primary domains has been analyzed, including those found in the now completely sequenced genomes of Haemophilus influenzae, Mycoplasma genitalium, Synechocystis sp., Methanococcus jannaschii, and Saccharomyces cerevisiae . The ubiquity of his genes suggests that it is a highly conserved pathway that was probably already present in the last common ancestor of all extant life . The chromosomal distribution of the his genes shows that the enterobacterial histidine operon structure is not the only possible organization, and that there is a diversity of gene arrays for the his pathway . Analysis of the available sequences shows that gene fusions (like those involved in the origin of the Escherichia coli and Salmonella typhimurium hisIE and hisB gene structures) are not universal . In contrast, the elongation event that led to the extant hisA gene from two homologous ancestral modules, as well as the subsequent paralogous duplication that originated hisF, appear to be irreversible and are conserved in all known organisms . The available evidence supports the hypothesis that histidine biosynthesis was assembled by a gene recruitment process.

FEBS Lett, 1998 Aug 14, 433(1-2), 108 - 12
Evolution of new protein function: recombinational enhancer Fis originated by horizontal gene transfer from the transcriptional regulator NtrC; Morett E et al.; New protein function is thought to evolve mostly by gene duplication and divergence . Here we present phylogenetic evidence that the multifunctional protein Fis of the gamma proteobacterial species derived from the COOH-terminal domain of an ancestral alpha proteobacterial NtrC transcriptional regulatory protein . All of the known enterobacterial fis genes are preceded by an open reading frame, named yhdG, that is highly similar to nifR3, a gene that forms an operon with ntrC in several alpha proteobacterial species . Thus, we propose that yhdG and fis were acquired by a lineage ancestral to the gamma proteobacteria in a single horizontal gene transfer event, and later diverged to their present functions.

J Clin Microbiol, 1998 Oct, 36(10), 3085 - 7
Molecular epidemiology of an outbreak of Enterobacter cloacae in the neonatal intensive care unit of a provincial hospital in Gauteng, South Africa; van Nierop WH et al.; An outbreak of Enterobacter cloacae in the neonatal intensive care unit of a provincial hospital in Gauteng, South Africa, resulting in nine deaths was investigated . Macrorestriction analysis using pulsed-field gel electrophoresis revealed that three isolates of E . cloacae from blood cultures of patients, six from environmental sources, and one from the hands of a staff member belonged to the same genotypic cluster.

J Clin Microbiol, 1998 Oct, 36(10), 3055 - 6
Isolation of Enterobacter intermedium from the gallbladder of a patient with cholecystitis; O'Hara CM et al.; We describe the isolation and identification of Enterobacter intermedium from the gallbladder of a patient with cholecystitis . There have been only four documented isolations of this organism from humans; it normally occurs in surface water and unpolluted soils . The identification was initially made by a MicroScan Walk/Away system with a Neg Combo 18 conventional identification-susceptibility panel . The organism is susceptible to the aminoglycosides and imipenem but resistant to the cephalosporins and ciprofloxacin.

J Clin Microbiol, 1998 Oct, 36(10), 2973 - 81
Comparison of different DNA fingerprinting techniques for molecular typing of Bartonella henselae isolates; Sander A et al.; Seventeen isolates of Bartonella henselae from the region of Freiburg, Germany, obtained from blood cultures of domestic cats, were examined for their genetic heterogeneity . On the basis of different DNA fingerprinting methods, including pulsed-field gel electrophoresis (PFGE), enterobacterial repetitive intergenic consensus (ERIC)-PCR, repetitive extragenic palindromic (REP) PCR, and arbitrarily primed (AP)-PCR, three different variants were identified among the isolates (variants I to III) . Variant I included 6 strains, variant II included 10 strains, and variant III included only one strain . By all methods used, the isolates could be clearly distinguished from the type strain, Houston-1, which was designated variant IV . A previously published type-specific amplification of 16S rDNA differentiated two types of the B . henselae isolates (16S rRNA types 1 and 2) . The majority of the isolates (16 of 17), including all variants I and II, were 16S rRNA type 2 . Only one isolate (variant III) and the Houston-1 strain (variant IV) comprised the 16S rRNA type 1 . Comparison of the 16S rDNA sequences from one representative strain from each of the three variants (I to III) confirmed the results obtained by 16S rRNA type-specific PCR . The sequences from variant I and variant II were identical, whereas the sequence of variant III differed in three positions . All methods applied in this study allowed subtyping of the isolates . PFGE and ERIC-PCR provided the highest discriminatory potential for subtyping B . henselae strains, whereas AP-PCR with the M13 primer showed a very clear differentiation between the four variants . Our results suggest that the genetic heterogeneity of B . henselae strains is high . The methods applied were found useful for typing B . henselae isolates, providing tools for epidemiological and clinical follow-up studies.

J R Coll Surg Edinb, 1998 Aug, 43(4), 278 - 82
Bacterial translocation in thioacetamide induced liver cirrhosis in rats; al-Bader AA et al.; Cirrhotic liver is predisposed to bacterial infections . Different species of bacteria including Escherichia coli, Enterobacter and Bacteroides fragilis were found to colonize thioacetamide-induced cirrhotic rat liver . Zinc treatment of the cirrhotic rats significantly corrected the histological and histochemical changes in the liver . However, this reversal with zinc treatment was not accompanied by any change in the bacterial colonies in the liver . The study shows that cirrhosis predisposes liver to bacterial colonization and the process is not reversible despite the partial reversal of the cirrhotic changes.

J Rheumatol, 1998 Sep, 25(9), 1756 - 64
Antibody response to Klebsiella pneumoniae 60 kDa protein in familial and sporadic ankylosing spondylitis: role of HLA-B27 and characterization as a GroEL-like protein; Cancino-Diaz ME et al.; OBJECTIVE: To study the antibody response of HLA-B27+ patients with ankylosing spondylitis (AS) and their first degree relatives to the 60 kDa protein of Klebsiella pneumoniae and to characterize this protein . METHODS: Sera from 84 individuals were analyzed by ELISA to determine the titer of antibodies against the 60 kDa protein of K . pneumoniae . Subjects were divided into 3 categories: Group 1: 44 HLA-B27+ AS related individuals (35 patients, 9 healthy controls); Group 2: 28 healthy B27- AS related individuals; and Group 3: 12 healthy B27- non-AS related subjects . The 60 kDa protein of K . pneumoniae was induced at 45 degrees C and purified by electroelution from sodium dodecyl sulfate-polyacrylamide gel electrophoresis . It was characterized as a GroEL-like heat shock protein (HSP) . The recognition of GroEL-like protein was confirmed by immunoblot of 2 dimension electrophoresis . The response to GroEL-like protein from other bacteria and the response to lipopolysaccharide (LPS) was also analyzed by immunoblot . RESULTS: HLA-B27+ individuals (Group 1), independent of their disease status, showed a significant higher response to the 60 kDa protein of K . pneumoniae than HLA-B27- subjects from Groups 2 and 3 (p < 0.0001) . This protein was characterized as a HSP of the GroEL family and designated HSP60Kp . The GroEL of other enterobacteria as well as that of Mycobacterium leprae were recognized by HLA-B27+ individuals by immunoblot, whereas HLA-B27- individuals did not . LPS was not recognized by HLA-B27 positive or negative subjects . CONCLUSION: These findings suggest a relationship between HLA-B27 and the response to a GroEL-like protein that could have implications in AS.

Arch Microbiol, 1998 Oct, 170(4), 243 - 51
High genetic and physiological diversity of sulfate-reducing bacteria isolated from an oligotrophic lake sediment; Sass H et al.; The community structure of sulfate-reducing bacteria in littoral and profundal sediments of the oligotrophic Lake Stechlin (Germany) was investigated . A collection of 32 strains was isolated from the highest positive dilutions of most-probable-number series, and their partial 16S rRNA gene sequences and genomic fingerprints based on ERIC (enterobacterial repetitive intergenic consensus)-PCR were analyzed . The strains fell into eight distinct phylogenetic lineages, and the majority (70%) showed a close affiliation to the genus Desulfovibrio . Most of the remaining strains (22%) were related to the gram-positive Sporomusa and Desulfotomaculum groups . A high redundancy of 16S rRNA gene sequences was found within several of the phylogenetic lineages . This low phylogenetic diversity was most pronounced for the subset of strains isolated from oxic sediment layers . ERIC-PCR revealed that most of the strains with identical 16S rRNA gene sequences were genetically different . Since strains with identical 16S rRNA gene sequences but different genomic fingerprints also differed considerably with respect to their physiological capabilities, the high diversity detected in the present work is very likely of ecological relevance . Our results indicate that a high diversity of sulfate-reducing bacterial strains can be recovered from the natural environment using the established cultivation media.

Chemotherapy, 1998 Sep-Oct, 44(5), 313 - 7
Effect of different beta-lactams in combination with beta-lactamase inhibitors in the presence or absence of tobramycin against some enterobacteriaceae producing extended-spectrum beta-lactamases; Ferrara A et al.; Extended-spectrum beta-lactamase (ESBL) production among members of the family Enterobacteriaceae generally involves resistance to oxyimino-cephalosporins and monobactams, while implying different susceptibility profiles with other antimicrobial agents . We have investigated the activity of some beta-lactam antibiotics, alone or in double and triple combinations with beta-lactamase inhibitors, in the presence or absence of tobramycin (TOB), against some Enterobacteriaceae producing ESBL by means of time-kill curves . Antimicrobials employed were ceftazidime (CAZ), cefotaxime (CTX), TOB, ampicillin (AMP), ampicillin-sulbactam (ASL), amoxicillin (AML), amoxicillin-clavulanic acid (AMC), piperacillin (PIP) and piperacillin-tazobactam (TZP), at 1/4 minimum inhibitory concentration for susceptible strains and at achievable serum concentrations for resistant strains . Only the combinations CTX-ASL, CAZ-ASL and PIP-ASL were synergistic, both at 6 and 24 h, on some strains of Klebsiella species.

Int J Syst Bacteriol, 1998 Apr, 48 Pt 2, 605 - 10
Phylogenetic relationships of Salmonella based on rRNA sequences; Christensen H et al.; To establish the phylogenetic relationships between the subspecies of Salmonella enterica (official name Salmonella choleraesuis), Salmonella bongori and related members of Enterobacteriaceae, sequence comparison of rRNA was performed by maximum-likelihood analysis . The two Salmonella species were separated by 16S rRNA analysis and found to be closely related to the Escherichia coli and Shigella complex by both 16S and 23S rRNA analyses . The diphasic serotypes S . enterica subspp . I and VI were separated from the monophasic serotypes subspp . IIIa and IV, including S . bongori, by 23S rRNA sequence comparison.

Urology, 1998 Sep, 52(3), 411 - 5; discussion 415-6
The in vitro bactericidal effect of microwave energy on bacteria that cause prostatitis; Sahin A et al.; OBJECTIVES: We investigated the in vitro nonthermal effects of microwaves delivered from Prostatron 2.0 on Escherichia coli and Enterobacter cloacae . METHODS: The fingers of powder-free, sterile gloves were ligated, and bacterial solutions were transferred into the remaining area of the glove . The gloves were then sealed using silk ligatures . One set of gloves was subjected to the microwave treatment while another set was placed in a temperature-matched waterbath to act as control samples . The gloves containing the treatment group were taped around the probe, at the site where microwave energy exits the probe . During the treatment period, the temperatures from the urethral probe and the rectal probe were carefully monitored . RESULTS: The mean (+/-SD) energy delivered was 46.6 +/- 9.5 kJ (range 30.0 to 59.5) for the 10 trials on E . coli and colony counts in the experimental microwaved gloves decreased significantly compared with control samples (5.26 +/- 4.5 x 10(5) versus 10.16 +/- 9.3 x 10(5) CFU/mL, P = 0.02) . For the experiments on E . cloacae the mean (+/-SD) energy applied was 38.5 +/- 12.5 kJ, and a significant decrease in colony counts of microwaved samples was also observed compared with controls (11.04 +/- 4.8 x 10(5) versus 20.08 +/- 10.1 x 10(5) CFU/mL, P = 0.004) . CONCLUSIONS: Microwave energy, delivered from Prostatron 2.0, independent of heat production has an in vitro bactericidal effect on laboratory-cultured E . coli and E . cloacae.

J Perinatol, 1998 Jul-Aug, 18(4), 291 - 6
Radiological pulmonary changes during gram-negative bacillary nosocomial bloodstream infection in premature infants; Cordero L et al.; OBJECTIVE: The objective of the study was to characterize the changes that occur in chest radiographs at the time of gram-negative bacilli (GNB) nosocomial bloodstream infection (BSI) and to determine the contribution of bronchopulmonary dysplasia (BPD) and airway gram-negative bacterial pathogens to the clinical diagnosis of GNB nosocomial pneumonia . STUDY DESIGN: This retrospective investigation involved 41 BSI infants (study group) and 50 GNB airway colonized infants who had sepsis workup with negative blood cultures (control group) . We correlated clinical findings (95 blood and 305 tracheal aspirate (TA) cultures) with radiographic findings noted within 2 days before, the day of, and the day after blood cultures . Two radiologists independently graded 258 films using a modified score for BPD and a semiquantitative score ("probable," "possible," or "unlikely") for pneumonia . RESULTS: Mean birth weight was 1057 gm and 1044 gm for the study and control groups, respectively . Of the study population, 54% were male, 21% were black, 89% received surfactant, 79% received dexamethasone, and 88% survived . Average age at the time of blood cultures for both groups was 23 days . Most common isolates from blood and TA were Klebsiella pneumoniae, Enterobacter cloacae, Escherichia coli, and Pseudomonas aeruginosa . Eight BSI infants died, mainly as a result of P . aeruginosa and K . pneumoniae; three control patients also died . Radiological findings were that BPD scores did not change in relation to BSI and were similar between study and control groups . Of the BSI patients, 21 presented with newly positive TA at the time of positive blood culture; "probable" or "possible" pneumonia was diagnosed in 18 of them . Their BPD scores were higher than those of the remaining BSI patients, of whom seven were already airway colonized, nine had negative TAs, and four were not intubated . Only one of these 20 patients had "possible" pneumonia noted on chest x-ray films . CONCLUSION: Radiographic signs of air space disease accompanied by the recovery of GNB respiratory pathogens from the blood and from a previously uncolonized airway strongly support the clinical diagnosis of GNB nosocomial pneumonia . Radiological signs of BPD are stable in relation to nosocomial BSI caused by GNB, but BPD radiological scores are higher among infants who also had a newly acquired respiratory GNB . BSI, new respiratory tract GNB, and BPD are critical associations for the clinical interpretation of radiographic changes in the ventilated newborn.

Appl Environ Microbiol, 1998 Sep, 64(9), 3214 - 9
In vitro and In vivo characterization of a small-colony variant of the primary form of photorhabdus luminescens MD (Enterobacteriaceae)
Hu K, Webster JM.
A small-colony variant (Vsm) of the primary form (Vp) of Photorhabdus luminescens MD from in vitro and in vivo cultures is described . Unlike the primary form, Vp, the Vsm variant is not the preferred diet of its nematode symbiont, a Heterorhabditis sp., does not support development and reproduction of the nematode, and is less pathogenic than Vp to Galleria mellonella larvae . Vsm cells were carried by 25% of infective juveniles, but they comprised a very low percentage ( approximately 0.4%) of the total cells carried by the juvenile . In vitro subculture and in vivo injection into the larvae with either Vp or Vsm always produced a mixture of both Vp and Vsm . In nematode-bacterium-infected G . mellonella larvae, the Vp population in the hemocoel was high (4 x 10(9) to 5 x 10(9) CFU/g of wet insect tissue) at 24 h after infection, decreased about 10-fold by 48 h, and then regained a high level at day 5 before decreasing at day 7 and then remaining relatively constant through day 15 postinfection . The Vsm population, under the same conditions as those of Vp, increased gradually to a high level (9 x 10(8) CFU/g of wet insect tissue) at day 5 postinfection and then declined gradually through day 15.

Curr Opin Rheumatol, 1998 Jul, 10(4), 282 - 91
HLA-B27 and other predisposing factors in spondyloarthropathies; Khare SD et al.; Studies from around the world have confirmed the association between HLA-B27 and human spondyloarthropathies . The onset of many HLA-B27-linked arthritides follows an infection with enterobacteria . How bacteria interact with HLA-B27 and modify the immune system to give rise to the clinical disease is currently unclear . The roles of other genetic factors, including major histocompatibility complex class II genes and other genes located within this region (Tap/Lmp), have been postulated in certain spondyloarthropathies . We are using transgenic and knockout mice to answer some of these unsolved issues . This review discusses recent findings from our laboratories.

Lett Appl Microbiol, 1998 Jul, 27(1), 24 - 30
An evaluation of ERIC PCR and AP PCR fingerprinting for discriminating Salmonella serotypes; Burr MD et al.; PCR fingerprints of 89 Salmonella isolates belonging to 22 serotypes were obtained using ERIC PCR (enterobacterial repetitive intergenic consensus PCR) and AP PCR (arbitrarily primed PCR) to evaluate the ability of different fingerprinting methods to differentiate or identify serotypes and subtypes . Fingerprints were scored and comparisons were made using a computer program . ERIC PCR produced a unique, complex fingerprint for almost every isolate, but these fingerprints did not identify serotypes . One AP PCR primer also produced complex fingerprints that discriminated among isolates, but again did not identify serotypes . A second AP PCR primer produced simple patterns, including one pattern shared by 35 isolates from 12 different serotypes . In general, the three sets of PCR fingerprints distinguished isolates, but were not correlated with serotypes . Matching fingerprints from different gels by computer was difficult, since similarities were based on both intense and faint bands . In addition, this study suggests that dendrograms created from PCR fingerprints should be viewed with caution.

Turk J Pediatr, 1998 Jan-Mar, 40(1), 17 - 33
Antibiotic use in neonatal sepsis; Yurdakok M; Neonatal sepsis is a life-threatening emergency and any delay in treatment may cause death . Initial signs of neonatal sepsis are slight and nonspecific . Therefore, in suspected sepsis, two or three days empirical antibiotic therapy should begin immediately after cultures have been obtained without awaiting the results . Antibiotics should be reevaluated when the results of the cultures and susceptibility tests are available . If the cultures are negative and the clinical findings are well, antibiotics should be stopped . Because of the nonspecific nature of neonatal sepsis, especially in small preterm infants, physicians continue antibiotics once started . If a baby has pneumonia or what appears to be sepsis, antibiotics should not be stopped, although cultures are negative . The duration of therapy depends on the initial response to the appropriate antibiotics but should be 10 to 14 days in most infants with sepsis and minimal or absent focal infection . In infants who developed sepsis during the first week of life, empirical therapy must cover group B streptococci, Enterobacteriaceae (especially E . coli) and Listeria monocytogenes . Penicillin or ampicillin plus an aminoglycoside is usually effective against all these organisms . Initial empirical antibiotic therapy for infants who developed sepsis beyond the first days of life must cover the organisms associated with early-onset sepsis as well as hospital-acquired pathogens such as staphylococci, enterococci and Pseudomonas aeruginosa . Penicillin or ampicillin and an aminoglycoside combination may also be used in the initial therapy of late-onset sepsis as in cases with early-onset sepsis . In nosocomial infections, netilmicin or amikacin should be preferred . In cases showing increased risk of staphylococcal infection (e.g . presence of vascular catheter) or Pseudomonas infection (e.g . presence of typical skin lesions), antistaphylococcal or anti-Pseudomonas agents may be preferred in the initial empirical therapy . In some centers, third-generation cephalosporins in combinations with penicillin or ampicillin have been used in the initial therapy of early-onset and late-onset neonatal sepsis . Third-generation cephalosporin may also be combined with an aminoglycoside in places where aminoglycoside-resistance to this antibiotic is high . However, third-generation cephalosporins should not be used in the initial therapy of suspected sepsis, because 1) extensive use of cephalosporins for initial therapy of neonatal sepsis may lead to the emergence of drug-resistant microorganisms (this has occurred more rapidly as compared with the aminoglycosides), 2) Antagonistic interactions have been demonstrated when the other beta-lactam antibiotics (e.g . penicillins) were combined with cephalosporins . Infections due to gram-negative bacilli can be treated with the combination of a penicillin-derivative (ampicillin or extended-spectrum penicillins) and an aminoglycoside . Third-generation cephalosporins in combination with an aminoglycoside or an extended-spectrum penicillin have been used in the treatment of sepsis due to these organisms . Piperacillin and azlocillin are the most active of extended-spectrum penicillins against Pseudomonas aeruginosa . Among the third-generation cephalosporins, cefoperazone and ceftazidime possess anti-Pseudomonas activity . Ceftazidime was found to be more active in vitro against Pseudomonas than cefoperazone or piperacillin . New antibiotics for gram-negative bacteria resistant to other agents are carbapenems, aztreonam, quinolones and isepamicin . Enterococci can be treated with a cell wall-active agent (e.g . penicillin, ampicillin, or vancomycin) and an aminoglycoside . Staphylococci are susceptible to penicillinase-resistant penicillins (e.g . oxacillin, nafcillin and methicillin) . Resistant strains are uniformly sensitive to vancomycin . A penicillin or vancomycin and an aminoglycoside combination result in a more rapid bacteriocidal effect than is produced by either dr

Gastrointest Endosc, 1998 Aug, 48(2), 137 - 42
Natural bioburden levels detected on flexible gastrointestinal endoscopes after clinical use and manual cleaning; Chu NS et al.; BACKGROUND: Colonoscopes present a special bacterial decontamination challenge because the colon has a large and diverse microbial population . METHODS: Bioburden of colonoscope insertion tube surfaces and suction channels were determined after use and after manual cleaning . RESULTS: After use bioburden in suction channels averaged 7.0 x 10(9) colony-forming units (cfu) . Cleaning reduced this level to 1.3 x 10(5) . Cleaning of tube surfaces reduced the after-use bioburden from a level of 5.1 x 10(5) to 2.2 x 10(4) cfu . Gram-negative rods accounted for approximately 99% of the bioburden within the suction channel after use and after cleaning . After use flora were predominantly Escherichia coli and Bacteroides . The flora shifted to waterborne Pseudomonas organisms, and other members of the family Enterobacteriaceae after cleaning . Gram-positive bacteria were the primary isolates from the device surfaces both after use (56%) and after cleaning (47%) . Because gram-positive cocci and diphtheroids are a part of the normal microbiota of the skin, these bacteria may have been introduced by the hospital environment or by handling . CONCLUSIONS: After the cleaning of in-use colonoscopes, fewer than 10(6) vegetative bacteria could be recovered . This value is several logs lower than some previous estimates . This finding may be useful in the formulation of sterilization and disinfection cycles . Microflora from the colonoscopes indicated that the cleaning process introduced waterborne and enteric microorganisms, which highlights the importance of sanitation in the device reprocessing area.

Lett Appl Microbiol, 1998 Jun, 26(6), 427 - 31
The comparative effects of nitrogen and oxygen on the microflora of beef steaks in carbon dioxide-containing modified atmosphere vacuum skin-packaging (MA-VSP) systems; Coventry MJ et al.; The effects of 80% oxygen-20% carbon dioxide (O2-CO2) and 80% nitrogen-20% carbon dioxide (N2-CO2) atmospheres were compared with respect to the microbial and sensory characteristics of vacuum skin-packaged grain-fed beef steaks stored at -1 and 4 degrees C . In both N2-CO2 and O2-CO2 atmospheres, lactobacilli were predominant over Brochothrix, pseudomonads, enterobacteria and yeasts and moulds . The results of the current investigation showed that the O2-CO2 atmospheres did not yield total viable counts in excess of 10(5) cfu cm-2 on beef steaks after 4 weeks of storage . However, the sensory analysis and thiobarbituric acid (TBA) values (as a measure of oxidative rancidity) of the products were unacceptable at this time . In contrast, the N2-CO2 atmospheres yielded maximum total viable counts of approximately 10(7) cfu cm-2 and the sensory analysis and TBA values of the product were judged to be acceptable after 4 weeks of storage at -1 degree C . These results indicate that sensory effects of the product were influenced to a greater extent by the chemical effects of high concentration of O2 on rancidity than by the high levels of lactobacilli.

Int J Antimicrob Agents, 1998 May, 10(2), 165 - 8
Current antimicrobial susceptibility of cutaneous bacteria to first line antibiotics; Korting HC et al.; Antimicrobial susceptibility of common bacterial species occurring on human skin appears to be falling . Data for the antimicrobial susceptibility of major groups of bacteria isolated from human skin during routine cultures were complied and analysed over a period of 9 months . Routine diagnostics of specimens from skin lesions and normal human skin were analysed for the presence of specified groups of bacteria . The species were identified using standard methods . Anti-microbial susceptibility was determined using a broth microdilution system giving breakpoints, the Sensititre system . Of the 333 Staphylococcus aureus, 129 Streptococcaceae, 180 Enterobacteriaceae and 120 Pseudomonadaceae strains investigated more than 5% of Staphylococcus aureus strains were resistant to flucloxacillin and thus methicillin (MRSA) . More than 25% of Staphylococcus aureus strains were resistant to tetracycline and erythromycin . Many MRSA strains were found multi-resistant . Gentamicin was active against a large majority of Enterobacteriaceae strains but many Pseudomonadaceae strains were resistant . Compared with previous corresponding surveys methicillin-resistant Staphylococcus aureus strains are clearly on the increase . To prevent a further increase of resistant strains a defined strategy for antibiotic use is needed in dermatology.

J Food Prot, 1998 Aug, 61(8), 960 - 3
Development of a model for evaluation of microbial cross-contamination in the kitchen; Zhao P et al.; Foods can become contaminated with pathogenic microorganisms from hands, the cutting board, and knives during preparation in the kitchen . A laboratory model was developed to determine occurrence of cross-contamination and efficacy of decontamination procedures in kitchen food-handling practices . Enterobacter aerogenes B199A, an indicator bacterium with attachment characteristics similar to that of Salmonella spp., was used . Chicken meat with skin inoculated with 10(6) CFU of E . aerogenes B199A/g was cut into small pieces on a sterile cutting board . The extent of cross-contamination occurring from meat to the cutting board and from the cutting board to vegetables (lettuce and cucumbers) subsequently cut on the board was determined . Swab samples from the cutting board, hand washings, and lettuce and cucumber samples revealed that approximately 10(5) CFU of E . aerogenes/cm2 were transferred to the board and hands and approximately 10(3) to 10(4) CFU of E . aerogenes/g to the lettuce and cucumbers . The surfaces of the cutting board and hands were treated with antibacterial agents after cutting the meat, and counts of E . aerogenes on the cutting board and vegetables (lettuce and cucumbers) were determined . Results revealed that use of the disinfectant reduced the population of E . aerogenes to almost nondetectable levels on the cutting boards . The average counts after treatment were < 20 CFU/g of vegetable and ranged from < 20 to 200 CFU per cm2 or g on the cutting board and subsequently on the vegetables . These results indicate that bacteria with attachment characteristics similar to Salmonella spp . can be readily transferred to cutting boards during food preparation and then cross-contaminate fresh vegetables if the boards are not cleaned . Application of a kitchen disinfectant can greatly reduce bacterial contamination on cutting boards.

Infect Immun, 1998 Sep, 66(9), 4389 - 96
alpha-GlcNAc-1-->2-alpha-glc, the Salmonella homologue of a conserved lipopolysaccharide motif in the Enterobacteriaceae, elicits broadly cross-reactive antibodies; Nnalue NA; To define cross-reactive epitopes in Salmonella lipopolysaccharide (LPS), antisera designated anti-S, anti-Ra, and anti-Re were generated against smooth (S), complete-core (Ra), and deep-core mutant (Re) strains, respectively, and characterized immunochemically . The reactivities of anti-Ra and anti-S with rough LPS (rLPS) chemotypes in enzyme-linked immunosorbent assays (ELISA) decreased progressively with increasing truncation of the complete-core oligosaccharide (e.g., Ra > Rb1 >.Re), while that of anti-Re increased (Ra < Rb1 <.Re) . Anti-Ra was relatively more reactive with nonhomologous smooth LPS (sLPS) than anti-S, which in turn was more reactive than anti-Re . This order reflected the relative reactivities of these sera with outer-core rLPS but not those with inner-core rLPS, which suggests that the cross-reactivities of all three sera with sLPS were mediated by antibodies which bind outer-core determinants . Anti-Ra, but not anti-S or anti-Re, reacted with molecules substituted by O chains in immunoblots and revealed ladder-like patterns in sLPSs of various serospecificities . Anti-Ra, however, did not react with O-antigen-specific neoglycoconjugates in ELISA, thus demonstrating specificity for core epitopes . Ra and Rb1 but not other Salmonella core chemotypes inhibited the reactivity of anti-Ra with sLPS in ELISA, which showed that the terminal outer-core disaccharide, alpha-GlcNAc-1-->2-alpha-Glc (GlcNAc-->Glc), was the major epitope of cross-reactive antibodies in the serum . GlcNAc-->Glc represents the conserved motif alpha-hexose-1-->2-alpha-hexose in cores of the Enterobacteriaceae, other homologues of which should likewise be cross-reactive . These results demonstrate that S or Re strains do not elicit cross-reactive antibodies and indicate that immunization with Ra strains may represent a general strategy for eliciting cross-reactive antibodies against LPSs from enteric bacteria.

Microb Pathog, 1998 Aug, 25(2), 77 - 90
Identification of PhoP-PhoQ activated genes within a duplicated region of the Salmonella typhimurium chromosome; Gunn JS et al.; Salmonellae virulence requires the PhoP-PhoQ two-component regulatory system . PhoP-PhoQ activate the transcription of genes following phagocytosis by macrophages which are necessary for survival within the phagosome environment . Thirteen previously undefined PhoP-activated gene fusions generated by MudJ and TnphoA (pag A, and E-P, respectively) were cloned and sequenced . Most pag products show no similarity to proteins in the database, while others are predicted to encode: a UDP-glucose dehydrogenase (pagA); a protein with similarity to the product of an E . coli aluminium-induced gene (pagH); a protein encoded within a Salmonella-unique region adjacent to the sinR gene (pagN); a protein similar to a product of the Yersinia virulence plasmid (pagO); and a protein with similarity to CrcA which is necessary for resistance of E . coli to camphor (pagP) . Of the pag characterized, only pagK, M and O were closely linked . pagJ and pagK were shown to be unlinked but nearly identical in DNA sequence, as each was located within a 1.6 kb DNA duplication . The translations of sequences surrounding pagJ and pagK show similarity to proteins from extrachromosomal elements as well as those involved in DNA transposition and rearrangement, suggesting that this region may have been or is a mobile element . The transcriptional start sites of pagK, M, and J were determined; however, comparison to other known pag gene promoters failed to reveal a consensus sequence for PhoP-regulated activation . DNA sequences hybridizing to a Salmonella typhimurium pagK specific probe were found in S . enteritidis but absent in other Salmonella serotypes and Enterobacteriaceae tested, suggesting that these genes are specific for broad host range Salmonellae that cause diarrhoea in humans . Cumulatively, these data further demonstrate: (1) that PhoP-PhoQ is a global regulator of the production of diverse envelope or secreted proteins; (2) that PhoP-PhoQ regulate the production of proteins of redundant function; and (3) that pag are often located in regions of horizontally acquired DNA that are absent in other Enterobacteriaceae .

FEMS Microbiol Lett, 1998 Aug 1, 165(1), 85 - 90
An extended-spectrum AmpC-type beta-lactamase obtained by in vitro antibiotic selection; Morosini MI et al.; A predictive approach was assayed to evaluate the possibility of mutant Amp-C beta-lactamase emergence with increased substrate spectrum (including new C-3' quaternary ammonium cephems) . The ampC gene encoding the AmpC beta-lactamase from Enterobacter cloacae was cloned and expressed in an AmpC-defective strain of E . coli . After the AmpC containing strain was challenged with cefpirome, an ampC variant encoding an enzyme with increased resistance to cefpirome and cefepime was selected . In addition, this variant conferred increased resistance to penicillins and third generation cephalosporins . The complete nucleotide sequence of the gene was determined . The deduced peptide sequence showed a single change with respect to the wild-type gene: valine to glutamic acid at position 318 of the native protein (298 of the mature enzyme) . The potential emergence and spread of this type of AmpC variants among pathogens should be considered.

FEMS Microbiol Lett, 1998 Aug 1, 165(1), 59 - 63
Examination of Serpulina pilosicoli for attachment and invasion determinants of Enterobacteria; Hartland EL et al.; The spirochaete, Serpulina pilosicoli, is the agent of intestinal spirochaetosis, a diarrhoeal disease of humans and other species . By mechanisms as yet unknown, large numbers of these spirochaetes intimately attach to the colonic mucosa by one cell end . In some infected individuals, the spirochaetes may invade the lamina propria and adjacent tissues, and they may cause spirochaetaemia . To examine S . pilosicoli for pathogenic determinants homologous with Enterobacteria, DNA was extracted from six strains of S . pilosicoli and hybridised at low stringency with DNA probes derived from the inv, ail and yadA genes of Yersinia enterocolitica, the eae gene from enteropathogenic Escherichia coli and a probe derived from the virulence plasmid of Shigella flexneri . No hybridisation of the enterobacterial probes to S . pilosicoli DNA was detected, indicating that these gene sequences, which are known to be involved in the attachment and invasion processes of the other intestinal pathogens, were not present in the spirochaetes.

Clin Infect Dis, 1998 Aug, 27 Suppl 1, S111 - 6
Infection in the intensive care unit: beta-lactamase-mediated resistance among Enterobacteriaceae and optimal antimicrobial dosing; Drusano GL; Class I beta-lactamase-mediated resistance in Enterobacteriaceae is increasingly common, clinically important, and often associated with previous use of third-generation cephalosporins . Extended-spectrum beta-lactamases that confer resistance to third-generation cephalosporins are also becoming more widespread . Beta-lactamase-producing organisms often display multiresistance, and this has been associated with increased mortality among patients . For all beta-lactam antimicrobials, the time that the plasma concentration exceeds the minimum inhibitory concentration (MIC) is the principal factor determining antibacterial activity . For concentration-dependent antimicrobials such as aminoglycosides and fluoroquinolones, the area under the plasma-concentration time curve:MIC ratio is the variable that has the strongest link to clinical outcome, particularly when relatively low peak: MIC values (< 10:1) are achieved . Peak concentration is of major concern for suppression of resistance . When high peak: MIC ratios (> or = 10:1) are achieved, this may suppress resistance and become the primary variable linked to outcome . When designing antimicrobial dosage regimens, it is important to take into account the pharmacodynamics of the drug in order to maximize the potential for achieving a positive clinical outcome and suppressing the emergence of bacterial resistance.

Clin Infect Dis, 1998 Aug, 27 Suppl 1, S100 - 6
Trends in beta-lactam resistance among Enterobacteriaceae; Nordmann P; beta-Lactam resistance among Enterobacteriaceae is related primarily to the emergence of novel beta-lactamases . The class A extended-spectrum beta-lactamases hydrolyze extended-spectrum beta-lactams and are inhibited by clavulanic acid . These beta-lactamases are divided in two groups: TEM and SHV derivatives and non-TEM and non-SHV extended-spectrum beta-lactamases (CTX-M1, CTX-M2, MEN-1, PER-1, PER-2, TOHO-1, and VEB-1) . The plasmid-mediated cephalosporinases (MIR-1, FOX-1, MOX-1, BIL-1, CMY-1, CMY-2, and LAT-1) hydrolyze extended-spectrum cephalosporins and cephamycins and are not inhibited by clavulanic acid . They have been reported in Europe and in the United States . The 15 inhibitor-resistant penicillinases are TEM derivatives (except for SHV-10) and plasmid mediated, and they are mainly from Escherichia coli isolates . The carbapenemases noted among Enterobacteriaceae are either the chromosomally located penicillinases (Sme-1, NmcA, IMI-1) found in rare Enterobacter cloacae or Serratia marcescens isolates or the plasmid-mediated metalloenzyme IMP-1 that is widespread in Japan . The incidence of resistance among Enterobacteriaceae related to the other more common beta-lactam-resistance mechanisms has continued to rise worldwide.

Clin Infect Dis, 1998 Aug, 27 Suppl 1, S42 - 7
Induction of beta-lactamase in Enterobacter cloacae; Wiedemann B et al.; beta-lactamase induction in Enterobacter cloacae, which is linked to peptidoglycan recycling, was investigated with use of high-performance liquid chromatography of cell wall fragments in genetically defined cells of Escherichia coli . After treatment of cells with beta-lactams, we detected in the periplasm an increase of D-tripeptide (N-acetylglucosaminyl-1,6 anhydro N-acetylmuramyl-L-alanyl-D-glutamyl-meso-diaminopimelic acid), D-tetrapeptide (N-acetylglucosaminyl-1, 6 anhydro N-acetylmuramyl-L-alanyl-D-glutamyl-meso-diaminopimelic acid -D-alanine), and a yet-unknown anhydromuropeptide . We identified this anhydromuramylpeptide by fast atom bombardment-mass spectrometry as anhydromuramyl-pentapeptide . The amount of these molecules did not alter after treatment with cell wall-active non beta-lactams . The transmembrane protein AmpG transports not only D-tripeptide but also D-pentapeptide into the cell . In the cytoplasm these molecules are degraded into the corresponding monosaccharide peptides M-tripeptide (N-acetylmuramyl-L-alanyl-D-glutamyl-meso-diaminopimelic acid) and M-pentapeptide (N-acetylmuramyl-L-alanyl-D-glutamyl-meso-diaminopimelic acid-alanine-D-alanine) . These findings indicate that besides M-tripeptide and D-tripeptide, probably M-tetrapeptide, D-tetrapeptide, M-pentapeptide, and D-pentapeptide are also signal muropeptides for beta-lactamase induction.

J Food Prot, 1998 May, 61(5), 620 - 2
Automated detection of hydrogen sulfide release from thiosulfate by Salmonella spp; Shelef LA et al.; Hydrogen sulfide production is used in conventional tests for identification and differentiation of Salmonella spp . from other species of Enterobacteriaceae, and a black precipitate on agar media is the indicator of the reaction . Selective liquid media were formulated for automated optical detection of H2S in salmonellae using the BioSys instrument . The media contained thiosulfate and ferric ammonium citrate, and production of H2S caused copious black pigmentation of the broth . Combination of the H2S indicators with dulcitol or xylose as fermentable carbohydrate, lysine, ornithine or arginine to induce decarboxylase activity, and Tergitol 4 as inhibitor selectively identified six Salmonella spp . by a sharp drop in transmittance at 585 nm . The time for detection of transmittance changes was inversely proportional to initial numbers of CFU in the media: 10 h for 10(5) CFU/ml and 17 h for 10(1) CFU/ml . No detection was observed in six non-Salmonella species of Enterobacteriaceae tested.

J Food Prot, 1998 May, 61(5), 608 - 15
Changes in biogenic amines and microbiological analysis in albacore (Thunnus alalunga) muscle during frozen storage; Ben-Gigirey B et al.; Albacore specimens of extra quality were analyzed for their biogenic amine contents after 1, 3, 6, and 9 months of frozen storage at -18 degrees C or -25 degrees C . A high-performance liquid chromatography method involving a linear elution gradient was optimized for the identification and determination of putrescine, cadaverine, histamine, spermidine, and spermine in albacore tuna . Putrescine was the biogenic amine that showed the highest increase, reaching concentrations of 59.04 ppm (815% of the initial level) and 68.26 ppm (942% of the initial level) in the white muscle of albacore after 9 months of frozen storage at -18 and -25 degrees C, respectively . Cadaverine, histamine, and spermidine concentrations were below 3, 5, and 11 ppm, respectively, after 9 months of frozen storage, while spermidine underwent a significant decrease at both storage temperatures . Microbiological analysis confirmed the absence of species of Enterobacteriaceae in 75% of the albacore specimens after 9 months of frozen storage; coliforms were always below 3 CFU/g . The survival rate of the psychrotrophic microorganisms after 9 months of frozen storage at -25 degrees C was 4.6%, while 38.9 and 92.1% of the aerobic mesophiles present in the white muscle of albacore before freezing survived 9 months of storage at -18 and -25 degrees C, respectively.

J Food Prot, 1998 May, 61(5), 601 - 7
Microbiological characterization of Serra da Estrela cheese throughout its Appellation d'Origine Protégée region; Tavaria FK et al.; The purpose of this study was to assess the typical microbiological quality of the most famous Portuguese traditional cheese, Serra da Estrela, and to assess its ripening time and geographical dependence . Ninety-six experimental cheeses manufactured from sixteen batches of milk on eight dairy farms scattered over the Appellation d' Origine Protegee (AOP) region were qualitatively and quantitatively evaluated microbiologically at various ripening times . Viable counts were performed after inoculation on appropriate selective media for aerobic mesophiles and proteolytic and lipolytic microflora, as well as lactococci, lactobacilli, species of Enterobacteriaceae, lactic streptococci, staphylococci, and yeasts . Members of the Enterobacteriaceae and lactic acid bacteria were the predominant microbial groups on all dairy farms throughout maturation; the latter are probably the microbial group responsible for most proteolytic and lipolytic breakdown in Serra da Estrela cheese . The microbial groups whose numbers were most affected by dairy-to-dairy variation were species of Enterobacteriaceae staphylococci, and enterococci, which are the most critical groups in terms of health hazards . It is therefore suggested that tighter control should be implemented at the level of choice of raw materials, in milk-handling practices, and in general throughout the manufacturing process in attempts to standardize production and consistently reduce microbiological risks (even though the distinctiveness of a few final organoleptic characteristics may somehow be reduced.

Surgery, 1998 Aug, 124(2), 418 - 28
Bacterially preexposed T cells impair bacterial elimination by non-Th1/Th2 cell mechanisms in a model of intra-abdominal infection; Gleason TG et al.; BACKGROUND: Escherichia coli preexposure in mice results in impaired elimination of subsequent intra-abdominal infections by a CD+4 T cell-dependent process . Certain gram-negative infections have been shown to induce T-helper-(Th)2 type CD4+ T-cell differentiation, which correlates with impaired elimination of infection and death . We hypothesized that E coli preexposure impairs subsequent bacterial elimination as a consequence of Th2 differentiation and that interleukin-12 (IL-12) treatment could reverse this differentiation and minimize the effects of E coli preexposure . METHODS: After preexposure to E coli or other species, BALB/c mice or interferon-gamma (INF-gamma)-deficient mice, treated with or without IL-12, were given a standard intra-abdominal infection (E coli, Bacteroides fragilis, and adjuvant) . Cohorts were killed for abscess quantification, in vitro T-cell proliferative responsiveness, and cytokine secretory profiles . Splenic lymphocytes preexposed in vivo to other types of bacteria were transferred to naive mice before intra-abdominal infection to determine whether preexposure, eliciting the lymphocyte-dependent response, was species specific . RESULTS: E coli preexposure alone caused no Th1 or Th2 shift; increased the proliferative responses of T cells; and, in combination with IL-12 therapy, caused markedly decreased IL-2 and IL-4 responses and an increased IFN-gamma response . IL-12 therapy did not change the response to intra-abdominal infection despite its ability to cause marked Th1 polarization . IFN-gamma-deficient mice responded to E coli preexposure no differently than did wild-type mice . Transfer of lymphocytes preexposed to Pseudomonas aeruginosa, Klebsiella pneumoniae, and hemolytic E coli but not other types of nosocomial pathogens caused the development of more abscesses just as transfer of E coli preexposed lymphocytes had . CONCLUSIONS: CD4+ T cells responsive to E coli preexposure regulate subsequent intra-abdominal abscess formation by a mechanism not explained by the Th1/Th2 paradigm . Preexposure to hemolytic E coli and other Enterobacteriaceae alters responses to intra-abdominal infection.

J Clin Microbiol, 1998 Sep, 36(9), 2686 - 9
Controlled comparative evaluation of BacT/Alert FAN and ESP 80A aerobic media as means for detecting bacteremia and fungemia; Doern GV et al.; During a one-year period, a total of 6,305 blood cultures were processed in a tertiary-care teaching hospital; 6 to 12 ml of blood was inoculated into both a BacT/Alert Fan aerobic bottle and an ESP 80A aerobic bottle . The FAN aerobic bottle contains an antimicrobial-absorbing material; the 80A aerobic bottle does not . Bottles were processed on their respective continuous-monitoring blood culture instruments for up to five days of incubation . Four hundred thirty-three cultures (6.9%) representing 301 septic episodes in 235 different patients yielded 490 bacteria or yeasts thought to be clinically significant . Two hundred seventy-five of the 433 presumed clinically significant positive cultures (63.5%) representing 195 septic episodes and yielding 301 isolates were positive in both FAN and 80A bottles . One hundred nine significant positive cultures (25.2%) (i.e., cultures positive with an organism judged to be of probable clinical significance) from 70 septic episodes yielded 126 isolates only in FAN bottles . Conversely, the 80A bottle was exclusively positive in 49 instances (11.3%), representing 36 septic episodes and yielding 63 isolates . The higher rates of significant positive blood cultures, numbers of septic episodes documented, and numbers of isolates recovered in FAN bottles versus 80A bottles were all statistically significant (P < 0.05) . Enhanced rates of detection of presumed clinically significant isolates in FAN bottles were largely accounted for by Staphylococcus aureus, members of the Enterobacteriaceae, and non-Pseudomonas aeruginosa miscellaneous gram-negative bacilli from patients receiving antimicrobial therapy at the time blood cultures were obtained . Enhanced recovery of one organism group, the beta-hemolytic streptococci, occurred in 80A . With one exception, detection times were essentially equivalent in the two systems . The single exception pertained to streptococci and enterococci, which were recovered significantly faster in 80A bottles . Three hundred thirty-eight of the 6,305 blood cultures evaluated in this study (5.4%) were judged likely to be contaminated . The percentages of probable contaminated cultures were as follows: 26.6% FAN and 80A; 42.3% FAN only; 31.1% 80A only (P < 0.05) . Finally, the instrument false-positive rates for the two systems were 0.7% with FAN and 3.0% with 80A (P < 0.05) . We conclude that while contamination rates were slightly higher with FAN than with 80A, use of FAN aerobic bottles in conjunction with the BacT/Alert system will yield significantly higher numbers of clinically significant blood culture isolates than 80A bottles and the ESP system . Furthermore, this enhanced detection is most conspicuous in patients receiving antimicrobial therapy at the time blood cultures are performed, probably due to the presence of an antimicrobial-absorbing material in FAN aerobic bottles.

Acta Vet Hung, 1998, 46(2), 219 - 29
Bacteriological investigations on wound myiasis of sheep caused by Wohlfahrtia magnifica (Diptera: Sarcophagidae); Toth E et al.; The aim of the present investigation was to get further information about obligate aerobic and facultatively anaerobic bacterial communities of the intact and Wohlfahrtia magnifica infested vulval region of sheep . The numbers of aerobic and facultatively anaerobic microorganisms were lower in samples taken from uninfested mucous membrane and myiatic wounds as well as in the wound fluid as compared to samples originating from the uninfested skin surface . Gram-negative bacteria belonging to the family Enterobacteriaceae were isolated only from the skin and mucous membrane of uninfested sheep . Gram-positive microorganisms dominated in all samples . The ratio of facultatively anaerobic bacteria was higher than 80% in the sample taken from a lesion containing third instar Wohlfahrtia larvae and in the wound discharge collected from a vulval wound free of maggots . It is suggested that there is a shift in the composition of the bacterial communities of vulva as staphylococci disappear from the wounds due to the presence of Wohlfahrtia larvae.

Mol Microbiol, 1998 Jul, 29(1), 219 - 34
Characterization of a novel RNA regulator of Erwinia carotovora ssp . carotovora that controls production of extracellular enzymes and secondary metabolites; Liu Y et al.; The enterobacterium Erwinia carotovora ssp . carotovora strain 71 (hereafter Ecc71) produces extracellular enzymes such as pectate lyase isozymes (Pels), cellulase (Cel), polygalacturonase (Peh) and protease (Prt) . These enzymes degrade plant cell wall components and are largely responsible for the elicitation of soft-rot diseases in plants and plant products . Ecc71 also produces HarpinEcc, the elicitor of hypersensitive reaction (HR) and the quorum-sensing signal, N-(3-oxohexanoyl)-L-homoserine lactone (OHL) . OHL controls extracellular enzyme and HarpinEcc production . The levels of these enzymes, as well as the expression of hrpNEcc, the structural gene for HarpinEcc, and ohll, the gene specifying OHL synthesis, are negatively regulated by RsmaA . rsmB, formerly aepH, on the other hand, positively regulates extracellular enzyme production . 6His-RsmA recombinant protein purified from E . coli binds rsmB RNA as indicated by gel mobility shift assays . rsmB comprises 547 bp DNA, which is transcribed from a single start site immediately after a sigma70-like promoter . In Ecc71, two rsmB RNA species are detected: a full-length 479 base rsmB RNA and a 259 base rsmB' RNA . rsmB' DNA hybridizes with the 259 base and the 479 base transcripts . A 3' RNase protection assay revealed that the 259 base and the 479 base RNA species end at the same position immediately after the putative rho-independent terminator . The expression of rsmB-lacZ transcriptional fusions established that the rsmB' RNA is not produced because of the activation of an internal promoter . These data strongly suggest that the 259 base rsmB' RNA is derived by processing of the primary rsmB RNA . In Ecc71, rsmB' expression driven by the lac promoter causes overproduction of Pel, Peh, Cel and Prt, and accumulation of pel-1, peh-1, hrpNEcc and ohll transcripts . By contrast, a plasmid with the rsmB' DNA sequence deleted fails to cause overproduction of the extracellular enzymes in Ecc71 . The rsmB' effect also occurs in Escherichia coli as glycogen accumulation is stimulated in the presence of rsmB' . In vivo and in vitro translation as well as mutational analysis of rsmB' have established that rsmB' RNA does not yield a translational product . Therefore, we concluded that the rsmB' RNA itself functions as the regulator . Indeed, the expression rsmB' DNA leads to neutralization of the negative effects of the RNA-binding protein, RsmA, in Ecc71 and Serratia marcescens strain SM274 . We propose a model that explains how RsmA and rsmB control the expression of genes for extracellular enzymes.

Rev Biol Trop, 1997 Dec, 45(4), 1445 - 52
{Microbiologic depuration of Anadara tuberculosa (Mollusca: Arcidae)}; Wong E et al.; In Costa Rica the mollusk Anadara tuberculosa represents a risk for human health due to the contamination of the growing waters and the fact that its is consumed raw . The families depending on the income obtained through commercialization of these animals have a low education and economic status . Therefore, it is of great importance to develop and evaluate simple methods of depuration that could be easily used by these families to make these mollusks safe for consumption . Bottles containing 11 of saline solution (25g/l) were prepared in duplicates to test the bactericidal effect of acetic acid . The solution in each bottle was adjusted to ph 4.5, 5.0 or 5.5 or held at ph of 7.0 or 8.0 for the controls . The solution in each bottle was then inoculated with approximately 1 X 104 cfu/ml of coliforms . Counts of coliforms were determined for each bottle 0, 1, 2, 4 and 8 hours after inoculation . For the depuration studies, specimens with diameters ranging from 4.0 to 4.5 cm were collected from a harvester at the estuary of Puntarenas, Gulf of Nicoya . Fifty specimens each were depurated in separate tanks containing 25 1 of oxygenated saline solution adjusted with acetic acid to an initial ph of 4.5 (treatment) or non adjusted ph of 8.0 (control) . Counts of Enterobacteriaceae were determined, in duplicates, every 12 hr for 48 hr . An additional fifty animals were depurated using the defined method and tested to determine if they met international standards of microbiological quality for aerobic plate count, Enterobacteriaceae count, Escherichia coli count and presence of Salmonella . A sensory evaluation using a triangle test was performed to compare a typical dish prepared with depurated or non-depurated animals . A significant coliform reduction was determined in a saline solution (25 g/l) at a pH range of 4.5 to 5.5 . This reduction, during 8 hr, was higher in the acid treatments compared to the controls . During depuration, the elimination of Enterobacteriaceae bacteria was faster when acetic was used (initial ph = 4.5) than when it was not . This elimination was more important the first 24 hr, time defined as adequate for the application of the method . The method has the advantage of transforming the bivalve in a product that is safe for human consumption, since it guarantees that the international standards of microbiological quality, for raw and depurated mollusks, are reached . On the other hand, the sensory qualities of a typical dish prepared with depurated animals are not affected by the method, which can be easily implemented and applied by the people that work in the extraction of this mollusk.

J Bacteriol, 1998 Aug, 180(16), 4056 - 67
Branched-chain amino acid biosynthesis in Salmonella typhimurium: a quantitative analysis; Epelbaum S et al.; We report here the first quantitative study of the branched-chain amino acid biosynthetic pathway in Salmonella typhimurium LT2 . The intracellular levels of the enzymes of the pathway and of the 2-keto acid intermediates were determined under various physiological conditions and used for estimation of several of the fluxes in the cells . The results led to a revision of previous ideas concerning the way in which multiple acetohydroxy acid synthase (AHAS) isozymes contribute to the fitness of enterobacteria . In wild-type LT2, AHAS isozyme I provides most of the flux to valine, leucine, and pantothenate, while isozyme II provides most of the flux to isoleucine . With acetate as a carbon source, a strain expressing AHAS II only is limited in growth because of the low enzyme activity in the presence of elevated levels of the inhibitor glyoxylate . A strain with AHAS I only is limited during growth on glucose by the low tendency of this enzyme to utilize 2-ketobutyrate as a substrate; isoleucine limitation then leads to elevated threonine deaminase activity and an increased 2-ketobutyrate/2-ketoisovalerate ratio, which in turn interferes with the synthesis of coenzyme A and methionine . The regulation of threonine deaminase is also crucial in this regard . It is conceivable that, because of fundamental limitations on the specificity of enzymes, no single AHAS could possibly be adequate for the varied conditions that enterobacteria successfully encounter.

Ear Nose Throat J, 1998 Jul, 77(7), 554 - 7
Cocaine and lidocaine with phenylephrine as topical anesthetics: antimicrobial activity against common nasal pathogens; Aldous WK et al.; Topical anesthetics are commonly used in the evaluation of nasal pathology . The anesthetics routinely used, 4% lidocaine with phenylephrine, or 4% cocaine, have been demonstrated to have varying inhibitory effects on bacterial cultures . The present study examined the antimicrobial activity of these topical anesthetics used in nasal procedures . The pathogens used were Branhamella catarrhalis, Enterobacter sp., Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus pneumoniae . Organisms were against two-fold serial dilutions of stock preparations of 4% lidocaine with 0.25% phenylephrine, 0.25% phenylephrine, 0.1% methylparaben, 250 mg/ml ampicillin, and 4% cocaine . The minimum inhibitory concentration and minimum bactericidal concentration for each of the solutions were obtained . The bacteria studied varied gently in their susceptibility to lidocaine with phenylephrine versus cocaine: Cocaine consistently exhibited greater antimicrobial activity than lidocaine . Phenylephrine and methylparaben showed slight antimicrobial activity . These topical anesthetics have slight bactericidal activity against nasal pathogens, which can sometimes lead to false-negative results . Otolaryngologists should recognize the possible antimicrobial effects of topical anesthetics when culturing specimens . This is especially important when the specimen will be used for guidance of antimicrobial therapy, as in the case of the critically ill patient who requires aspiration for organism-specific therapy . Further studies, specifically in vivo experiments, are needed to determine if use of the drugs produces a significant change in the ability to culture organisms from these sites . This type of study would, however, be difficult to perform, since most patients requiring aspiration are already on high-dose antibiotics that would inhibit the growth of most microorganisms . A modified aspiration technique using a less concentrated topical anesthetic will likely be required to increase the chances of obtaining positive cultures.

Clin Lab Sci, 1998 Sep-Oct, 11(5), 266 - 8
Comparison of four latex kits for detection of E . coli O157; Chan E et al.; OBJECTIVE: To compare four Escherichia coli O157 test kits for detection of E . coli O157:H7 isolated from clinical specimens . DESIGN: One hundred two Escherichia coli O157:H7 isolates obtained from stored specimens and 99 non-sorbitol fermenting enterobacteriaceae isolates from current clinical specimens were tested against four latex kits: Wellcolex, RIM, Prolex, and Oxoid . Each isolate was tested against all four kits on the same day . SETTING: Provincial Laboratory of Saskatchewan, Canada . PATIENTS: Patients from Saskatchewan with diarrhea submitted stool specimens through their family physicians to the Provincial Laboratory for detection of enteric pathogens including E . coli O157:H7 . RESULTS: The sensitivity and specificity of each test kit were: Wellcolex 100%, 99%; RIM 100%, 99%; Prolex 99%, 100%; Oxoid 100%, 100% . The Prolex kit failed to detect one E . coli O157:H7 isolate . CONCLUSION: All kits tested were able to identify E . coli O157 isolated from stool specimens . Further study with Prolex is needed to assess the significance of the one missed E . coli O157 isolate.

Appl Environ Microbiol, 1998 Aug, 64(8), 2864 - 8
Aerobic degradation of 2,4,6-trinitrotoluene by Enterobacter cloacae PB2 and by pentaerythritol tetranitrate reductase; French CE et al.; Enterobacter cloacae PB2 was originally isolated on the basis of its ability to utilize nitrate esters, such as pentaerythritol tetranitrate (PETN) and glycerol trinitrate, as the sole nitrogen source for growth . The enzyme responsible is an NADPH-dependent reductase designated PETN reductase . E . cloacae PB2 was found to be capable of slow aerobic growth with 2,4,6-trinitrotoluene (TNT) as the sole nitrogen source . Dinitrotoluenes were not produced and could not be used as nitrogen sources . Purified PETN reductase was found to reduce TNT to its hydride-Meisenheimer complex, which was further reduced to the dihydride-Meisenheimer complex . Purified PETN reductase and recombinant Escherichia coli expressing PETN reductase were able to liberate nitrogen as nitrite from TNT . The ability to remove nitrogen from TNT suggests that PB2 or recombinant organisms expressing PETN reductase may be useful for bioremediation of TNT-contaminated soil and water.

Antimicrob Agents Chemother, 1998 Aug, 42(8), 2048 - 54
Pharmacokinetics of {18F}trovafloxacin in healthy human subjects studied with positron emission tomography; Fischman AJ et al.; Tissue pharmacokinetics of trovafloxacin, a new broad-spectrum fluoroquinolone antimicrobial agent, were measured by positron emission tomography (PET) with {18F}trovafloxacin in 16 healthy volunteers (12 men and 4 women) . Each subject received a single oral dose of trovafloxacin (200 mg) daily beginning 5 to 8 days before the PET measurements . Approximately 2 h after the final oral dose, the subject was positioned in the gantry of the PET camera, and 1 h later 10 to 20 mCi of {18F}trovafloxacin was infused intravenously over 1 to 2 min . Serial PET images and blood samples were collected for 6 to 8 h, starting at the initiation of the infusion . Drug concentrations were expressed as the percentage of injected dose per gram, and absolute concentrations were estimated by assuming complete absorption of the final oral dose . In most tissues, there was rapid accumulation of the radiolabeled drug, with high levels achieved within 10 min after tracer infusion . Peak concentrations of more than five times the MIC at which 90% of the isolates are inhibited (MIC90) for most members of Enterobacteriaceae and anaerobes (>10-fold for most organisms) were achieved in virtually all tissues, and the concentrations remained above this level for more than 6 to 8 h . Particularly high peak concentrations (micrograms per gram; mean +/- standard error of the mean {SEM}) were achieved in the liver (35.06 +/- 5.89), pancreas (32.36 +/- 20 . 18), kidney (27.20 +/- 10.68), lung (22.51 +/- 7.11), and spleen (21 . 77 +/- 11.33) . Plateau concentrations (measured at 2 to 8 h; micrograms per gram; mean +/- SEM) were 3.25 +/- 0.43 in the myocardium, 7.23 +/- 0.95 in the lung, 11.29 +/- 0.75 in the liver, 9.50 +/- 2.72 in the pancreas, 4.74 +/- 0.54 in the spleen, 1.32 +/- 0.09 in the bowel, 4.42 +/- 0.32 in the kidney, 1.51 +/- 0.15 in the bone, 2.46 +/- 0.17 in the muscle, 4.94 +/- 1.17 in the prostate, and 3.27 +/- 0.49 in the uterus . In the brain, the concentrations (peak, approximately 2.63 +/- 1.49 microg/g; plateau, approximately 0.91 +/- 0.15 microg/g) exceeded the MIC90s for such common causes of central nervous system infections as Streptococcus pneumoniae (MIC90, <0.2 microg/ml), Neisseria meningitidis (MIC90, <0.008 microg/ml), and Haemophilus influenzae (MIC90, <0.03 microg/ml) . These PET results suggest that trovafloxacin will be useful in the treatment of a broad range of infections at diverse anatomic sites.

Antimicrob Agents Chemother, 1998 Aug, 42(8), 1996 - 2001
In vivo activity and pharmacokinetic evaluation of a novel long-acting carbapenem antibiotic, MK-826 (L-749,345); Gill CJ et al.; MK-826 (formerly L-749,345), is a potent 1-beta-methyl carbapenem with a long half-life and broad spectrum of activity . This compound is presently in phase-II clinical trials . Its activity against a number of gram-positive and gram-negative organisms was compared to those of imipenem (IPM) and eight other beta-lactam agents in two in vivo murine infection models . The distribution in tissue and pharmacokinetic properties of MK-826 and ceftriaxone (CTRX) were also evaluated in CD-1 mice following a single intraperitoneal dose (10 mg/kg of body weight) . In addition, concentrations in plasma as well as biliary and urinary recovery of MK-826 were compared to that of CTRX in a cannulated rat model . In a localized murine thigh infection model, MK-826 and IPM were superior to a variety of beta-lactam antibiotics in reduction of Staphylococcus aureus CFU compared with results from nontreated controls (eliminating >/=4 log10 CFU) . Similar activities of IPM and MK-826 were observed in a gram-positive bacterial murine systemic infection model . While IPM demonstrated greater efficacy than MK-826 against Enterobacter cloacae (50% effective doses {ED50s} of 0.062 and 0.227 mg/kg, respectively) and Pseudomonas aeruginosa (ED50s of 0.142 and 3.0 mg/kg, respectively) systemic infections, MK-826 was 8- to 350-fold more efficacious than IPM against all other gram-negative organisms in this infection model . In mice, MK-826 demonstrated a higher peak concentration in serum (62.8 versus 42.6 microg/ml) and a larger area under the curve (AUC) (150.8 versus 90.0 microg . hr/ml) than CTRX . The concentrations of MK-826 and CTRX in serum declined slowly, with levels of 3.6 and 2.0 microg/ml remaining, respectively, at 6 h posttreatment . The rat pharmacokinetic model showed the average AUC of MK-826 to be greater than that of CTRX (284 versus 142 microg . hr/ml) following a single 10-mg/kg dose . Also, a half-life of MK-826 longer than that of CTRX (3.2 versus 2.3 h) was observed in this species . The total amount of drug excreted in the bile in 8 h was greater for CTRX (55 to 64% of the dose) than for MK-826 (6 to 12.5% of the dose) . Urinary recovery was similar for both antibiotics, with 16 to 18% of the dose recovered over an 8-h period . This excellent broad-spectrum in vivo efficacy of MK-826, together with advantageous pharmacokinetics, supports the argument for its further clinical development.

Hepatogastroenterology, 1998 May-Jun, 45(21), 873 - 8
Pancreatic fluid collections: diagnostic and therapeutic implications of percutaneous drainage guided by ultrasound; Malecka-Panas E et al.; BACKGROUND/AIMS: The aim of the present study is to assess the usefulness of biochemical and bacteriological analysis of the pancreatic fluid obtained at percutaneous drainage of pancreatic pseudocysts and abscesses guided by ultrasound . METHODOLOGY: The study population was comprised of 65 patients, aged 21-79 years: 18 with abscesses and 47 with pseudocysts . In all cases the etiological factor of pancreatic fluid collections was acute pancreatitis . Microbiological (both of aerobic and anaerobic flora), biochemical (including alpha 2-macroglobulin) and cytological analysis of aspirated fluid was performed . Duration of percutaneous drainage in pseudocysts was 10-40 days (mean 18 +/- 12) and in abscesses 21-56 days (mean 32 +/- 19) . RESULTS: Complete resolution of pancreatic fluid collections was obtained in 54 (83%) patients, among them in 40 (85.1%) with pseudocysts and in 14 (77.7%) with abscesses, which was confirmed in follow-up ultrasound and/or computed tomography one year after the catheter was removed . Mild complications of this procedure observed in 17 (26.1%) patients were managed without catheter removal . A variety of organisms were cultured from pancreatic fluid, E . coli being the most prevalent . Enterobacter cloacae, staphylococcus aureus, staphylococcus epidermidis, peptococcus saccharolyticus, propionibacterium acnes and bacteroides fragilis were also isolated . Cytologic analysis of the aspirate revealed no atypical cells . The level of alpha 2-macroglobulin in the pancreatic fluid was significantly higher (p < 0.05) in patients with successful pancreatic drainage as compared to the remaining group . CONCLUSION: Percutaneous drainage represents a safe therapeutic method that also provides additional criteria for the management of patients with pancreatic cystic lesions.

J Bacteriol, 1998 Aug, 180(15), 3891 - 9
Chemical structure of lipid A isolated from Flavobacterium meningosepticum lipopolysaccharide; Kato H et al.; The chemical structure of the lipid A of the lipopolysaccharide component isolated from Flavobacterium meningosepticum IFO 12535 was elucidated . Methylation and nuclear magnetic resonance analyses showed that two kinds of hydrophilic backbone exist in the free lipid A: a beta (1-->6)-linked 2-amino-2-deoxy-D-glucose, which is usually present in enterobacterial lipid A's, and a 2-amino-6-O-(2, 3-diamino-2,3-dideoxy-beta-D-glucopyranosyl)-2-deoxy-D-glucose, in a molar ratio of 1.00:0.35 . Both backbones were alpha-glycosidically phosphorylated in position 1, and the hydroxyl groups at positions 4, 4', and 6' were unsubstituted . Liquid secondary ion-mass spectrometry revealed a pseudomolecular ion at m/z 1673 {M-H}- as a major monophosphoryl lipid A component carrying five acyl groups . Fatty acid analysis showed that the lipid A contained 1 mol each of amide-linked (R)-3-OH iC17:0, ester-linked (R)-3-OH iC15:0, amide-linked (R)-3-O-(iC15:0)-iC17:0, and both amide- and ester-linked (R)-3-OH C16:0 . Fatty acid distribution analyses using several mass spectrometry determinations demonstrated that the former two constituents were distributed on positions 2 and 3 of the reducing terminal unit of the backbones and that the latter two were attached to the 2' and 3' positions in the nonreducing terminal residue.

Farmaco, 1998 May 30, 53(5), 337 - 41
Synthesis and microbiological activity of some novel 5- or 6-methyl-2-(2,4-disubstituted phenyl) benzoxazole derivatives; Temiz O et al.; The synthesis of a new series of 5-or 6-methyl-2-(2,4-disubstituted phenyl) benzoxazoles (4, 5) is described in order to determine their antimicrobial activities and feasible structure-activity relationships . The synthesized compounds were tested in vitro against three Gram-positive bacteria, three Gram-negative bacteria and the yeast Candida albicans, in comparison with several control drugs . Microbiological results exhibited that the synthesized compounds possess a broad spectrum of antibacterial activity against the tested microorganisms . The compounds 4b and 4c indicated some antibacterial activity against Staphylococcus aureus having a minimum inhibitory concentration (MIC) of 12.5 micrograms/ml . Moreover, the compound 5a revealed a significant antibacterial activity against the enterobacter Pseudomonas aeruginosa showing a MIC value of 25 micrograms/ml, i.e . more potent than the control drugs tetracycline and streptomycin . For the antimycotic activity against the yeast C . albicans, the derivative 4c was found to be more active than the other synthesized compounds with a MIC value of 12.5 micrograms/ml, but one-fold less potent than the control drugs oxiconazole and haloprogin.

J Food Prot, 1998 Jul, 61(7), 785 - 91
Application of random amplified polymorphic DNA analysis for detection of Salmonella spp . in foods; Miyamoto T et al.; The random amplified polymorphic DNA (RAPD) band patterns from 23 Salmonella spp . produced by use of an oligonucleotide primer (called du primer) designed on the basis of the N-terminal sequence of dulcitol 1-phosphate dehydrogenase (5'-GTGGTGACCCAGGATGGCCAGGTG-3') were different from those from 16 non-Salmonella spp . The bands at 460 and 700 bp were produced in all Salmonella strains tested . These RAPD fragments obtained from Salmonella typhimurium strongly hybridized with the corresponding RAPD bands from the other strains of Salmonella, but not with those from non-Salmonella spp . in Southern blot analysis . The RAPD bands were detected by ethidium bromide staining even when genomic DNA prepared from as few as 2.8 x 10(3) cells was used . The minimum detectable cell number in the initial inoculum of S . typhimurium was 4 x 10(-1) CFU/25 g of raw beef after the preenrichment in Enterobacteriaceae enrichment mannitol (EEM) broth for 6 h and the selective enrichment in dulcitol-magnesium chloride-pyridinesulfonic acid-brilliant green-novobiocin (DMPBN) medium for 18 h at 42 degrees C . Seven raw foods inoculated with S . typhimurium at numbers from 4 x 10(-1) to 2.6 x 10(2) CFU/25 g of food were positive in both the RAPD analysis and the conventional culture method.

FEMS Microbiol Lett, 1998 Jul 1, 164(1), 83 - 90
Cloning and characterisation of the Proteus mirabilis xerD gene; Villion M et al.; The Xer site-specific recombination system is involved in the stable maintenance of replicons (certain plasmids and chromosomes) in Escherichia coli and other bacteria by converting multimers into monomers . This system requires a cis-acting DNA sequence (the chromosomal dif site or the ColE1 cer site) and two trans-acting factors: the XerC and XerD recombinases, which belong to the lambda integrase family of tyrosine site-specific recombinases . In addition, in order to resolve plasmid multimers into monomers, two additional factors are required: the ArgR and PepA proteins . We have previously shown the presence of xerC and xerD genes (and their function) by Southern hybridisation and by in vivo recombination in a wide variety of Enterobacteriaceac . We have now cloned and sequenced the xerD gene of Proteus mirabilis using degenerate and inverse PCR methods . This gene encodes a tyrosine recombinase which is highly similar to the E . coli XerD recombinase, is capable of complementing an E . coli xerD mutant, and displays sequence-specific DNA binding activity.

Clin Infect Dis, 1998 Jul, 27(1), 47 - 50
Pharmacodynamics of fluoroquinolones in experimental models of endocarditis; Andes DR et al.; We calculated the magnitude of various serum pharmacodynamic parameters for fluoroquinolones in models of experimental endocarditis (EE) described in the literature . Nineteen publications contained data that allowed calculation of these parameters . Data were available for eight fluoroquinolones against methicillin-susceptible Staphylococcus aureus, methicillin-resistant S . aureus, methicillin-resistant Staphylococcus epidermidis, viridans streptococci, Enterobacter aerogenes, and Pseudomonas aeruginosa in rabbit or rat models . Enterococci were excluded because of poor bactericidal activity . A 24-hour area under the concentration curve (AUC)/minimal inhibitory concentration (MIC) ratio > or = 100, a peak level/MIC ratio > 8, and continuous levels above the time were associated with a significantly lower number of cfu per vegetation after 3-6 days of therapy . The 24-hour AUC/MIC exhibited the best linear correlation with cfu per vegetation after 3-6 days of therapy (r2 = 45%) . The pharmacodynamic parameters predictive of efficacy for fluoroquinolones in the treatment of experimental endocarditis are similar to those for other infectious models.

Chest, 1998 Jul, 114(1), 120 - 30
Sparfloxacin vs ofloxacin in the treatment of acute bacterial exacerbations of chronic bronchitis: a multicenter, double-blind, randomized, comparative study . Sparfloxacin Multicenter ABECB Study Group; DeAbate CA et al.; STUDY OBJECTIVE: Comparison of efficacy and safety of sparfloxacin vs ofloxacin for treatment of acute bacterial exacerbations of chronic bronchitis (ABECB) . DESIGN: Multicenter, double-blind, randomized study . SETTING: Sixty-eight private offices and outpatient clinics in the United States and Canada . PATIENTS: Seven hundred ninety-eight adults with ABECB, as confirmed by the acute onset of new (or worsened from the immediate premorbid state) cough and sputum production . INTERVENTIONS: Randomization 1:1 to sparfloxacin, 400 mg on day 1, then 200 mg once daily, or ofloxacin, 400 mg twice daily, with matching comparator placebos, given concurrently for 10 consecutive days . RESULTS: The primary efficacy parameter was overall response in the bacteriologically evaluable population . Overall success rates in this population were 85.3% and 89.3% for sparfloxacin and ofloxacin, respectively . The two-sided 95% confidence interval was -9.9, 1.9, indicating that sparfloxacin was statistically equivalent to ofloxacin . The all-treated population analysis was similar to that in the evaluable population . Bacterial eradication rates were similar in both treatment groups for Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, Chlamydia pneumoniae, Haemophilus parainfluenzae, Klebsiella pneumoniae, Enterobacter cloacae, and Staphylococcus aureus . The frequency of adverse events overall was comparable in the two treatment groups . The sparfloxacin group had a lower frequency of digestive and nervous system adverse events, but a higher frequency of photosensitivity reactions than the ofloxacin group . CONCLUSIONS: Once-daily oral treatment with 200 mg sparfloxacin (after initial 400 mg dose) is as effective as twice-daily treatment with 400 mg ofloxacin in patients with ABECB.

J Appl Microbiol, 1998 May, 84(5), 802 - 10
Sensorial and microbial effects of gaseous ozone on fresh scad (Trachurus trachurus); da Silva MV et al.; The bactericidal activity of gaseous ozone was investigated using a commercial ozone generator . Five species of fish bacteria, Pseudomonas putida, Shewanella putrefaciens, Brochothrix thermosphacta, Enterobacter sp . and Lactobacillus plantarum, were inoculated on agar surfaces and exposed to different ozonation times in a gas chamber . Results showed ozone in relatively low concentrations (< 0.27 x 10(-3) g l-1) was an effective bactericide of vegetative cells of the five fish bacteria . The age of the cell culture was shown to influence the cell response following exposure . Survival rate was not linearly related to ozonation time, but exhibited biphasic death over an extended period . Similar bactericidal effects were observed on fish skin treated with ozone daily in the laboratory, with decreases of 1.0 log cfu cm-2 for the micro-organisms studied . Whole fish treated daily in the laboratory using a commercial ozone generator showed improved scores for sensory analyses compared with the controls . The results were statistically significant . Fish treated on board ships were also analysed for microbiological and sensory changes . Controls were obtained from a similar vessel without the ozone facility in the hold . Similar trends to those recorded in the laboratory for the microbiological and sensory results on ozonated fish were observed.

J Small Anim Pract, 1998 Jun, 39(6), 286 - 9
Comparative field evaluation of marbofloxacin tablets in the treatment of feline upper respiratory infections; Dossin O et al.; One hundred and three cats presenting with clinical signs of feline acute upper respiratory infection were selected from Belgium, France and the Netherlands in a randomised comparative field trial . Each cat underwent a bacteriological examination before treatment (day 0) and received either marbofloxacin, at a dosage of 2 mg/kg once daily for five days, or amoxycillin-clavulanic acid (ACA) at a dosage of 12.5 mg/kg twice daily for five days . Clinical examinations were performed on days 2, 5 and 14 . Pasteurella species were cultured in one-third of the samples . The other main bacteria isolated were Streptococcaceae, Enterobacteriaceae and Staphylococcaceae . Response rates (cures + improvements) to treatment on day 5 were 87.8 vs 77.8 per cent for marbofloxacin and ACA, respectively . A few mild side-effects (diarrhoea, vomiting) were recorded with both drugs.

Biochemistry, 1998 Jul 21, 37(29), 10461 - 8
Effect of an amino acid insertion into the omega loop region of a class C beta-lactamase on its substrate specificity; Nukaga M et al.; The extended-substrate specificity of Enterobacter cloacae GC1 beta-lactamase is entirely due to a three amino acid insertion after position 207 . To clarify the reason for the extended-substrate specificity, Ala, Ala-Ala, Ala-Ala-Ala, and Ala-Ala-Ala-Ala were inserted after position 207 on the basis of the class C beta-lactamase from E . cloacae P99, respectively . The kcat and Km values of all the mutant enzymes for cephalothin, benzylpenicillin and ampicillin were almost the same as those of the wild-type enzyme, except for those of P99-210-4A which were decreased 4-15-fold . On the other hand, the kcat and Km values for oxyimino beta-lactams such as cefuroxime, ceftazidime, and aztreonam increased with increasing numbers of inserted alanines . The kcat values of the mutant enzymes for cefroxime increased 140-7400-fold compared with that of the wild-type . The Km values also increased with almost the same magnitude, resulting in about the same kcat/Km values as that of the wild-type . On progressive inhibition analysis of aztreonam of the mutant enzymes, two kinds of inactive acyl-enzyme with distinct stabilities were observed, and the proportion of the less stable inactive enzyme increased with increasing numbers of inserted alanines . This suggests that the extension of the substrate specificity is due to instability of the acyl-intermediate caused by an increased deacylation rate in the reaction process.

Am J Med Sci, 1998 Jul, 316(1), 13 - 20
Microbiology of acute and chronic sinusitis in children and adults; Wald ER; The microbiology of infections of the paranasal sinuses can be anticipated according to the patient's age, clinical presentation, and immunocompetence . In acute sinus disease, viral upper respiratory infections frequently precede bacterial superinfection by Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis . Staphylococci and respiratory anaerobes are common in chronic sinus infection, which may also be caused by exacerbations of infection with the bacterial species that cause acute disease . Enterobacteriaceae may be found in patients with nosocomial sinusitis who are predisposed to the development of sinusitis by prolonged nasogastric and nasotracheal intubation . Immunosuppressed patients have episodes of sinusitis caused by the usual agents associated with acute sinusitis in immunocompetent patients, and they may also become infected with a broad array of unusual agents, including mycobacterial species, fungi, and protozoa.

Ann Med, 1998 Apr, 30(2), 176 - 85
Multiresistant bacteria as a hospital epidemic problem; Dennesen PJ et al.; Since the introduction of antibiotics into clinical use, bacteria have protected themselves by developing antibiotic resistance mechanisms . Currently, there are increasing problems worldwide with multiresistant bacteria . These problems are especially evident within hospitals, where they frequently present as nosocomial epidemics . Currently, the most important nosocomial resistance problems on a global scale are caused by methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci and Enterobacteriaceae with plasmid-encoded extended-spectrum beta-lactamases . In this review we describe the characteristics of nosocomial epidemics of these three groups of multiresistant nosocomial pathogens . Despite the differences in bacterial species, the differences in mechanisms of resistance, the different ecological niches and the different infections caused by these pathogens, there are striking similarities in the variables determining nosocomial spread . The existence of each of these multiresistant micro-organisms and their concurrent spread seem to result from extensive antibiotic use and lapses in compliance with infection control measures . Problems with these bacteria became evident as monoclonal outbreaks, soon followed by establishment of endemicity especially in intensive care units . Finally, endemicity seems to be established on general hospital wards and in chronic care facilities and nursing homes, creating a continuous influx of colonized patients into special care wards . High compliance with infection control measures and a prudent and more restrictive use of antibiotics are the key measures to prevent these epidemics.

Immunopharmacology, 1998 Mar, 39(1), 1 - 7
Displacement of platelets from blood to spleen following intravenous injection of liposomes encapsulating dichloromethylene bisphosphonate; Shibazaki M et al.; Liposomes encapsulating dichloromethylene bisphosphonate (Cl2MBP-liposomes) have been shown to cause selective depletion of phagocytic macrophages . We have shown that intravenous injection of Cl2MBP-liposomes into mice induces an almost complete depletion of F4/80-positive cells (mature macrophages) in the liver and in the splenic red pulp, but not in the lung . Platelets in the mouse contain a large amount of 5-hydroxytryptamine (5HT; serotonin) and so, by measuring 5HT, it is possible to assess the translocation of platelets to tissues . The injection of Cl2MBP-liposomes was found to induce a prolonged and marked increase in 5HT that occurred selectively in the spleen . On the other hand, 5HT in the blood decreased by as much as 50% . These changes in 5HT corresponded well with each other in terms of both time course and dose-response relationship . To judge from measurements made at the peak of the response, the 5HT increase in the spleen corresponded to about 80% of the 5HT lost from the blood . Electron microscopic analysis revealed a great accumulation of platelets in the splenic cords . We have shown that aggregation and degranulation of platelets in the lung is involved in rapid anaphylactoid shock induced within 10 min of intravenous injection into mice of a lipopolysaccharide {Shibazaki, M., Nakamura, M., Endo, Y., 1996 . Biphasic, organ-specific, and strain-specific accumulation of platelets induced in mice by a lipopolysaccharide from Escherichia coli and its possible involvement in shock . Infect . Immun . 64, 5290-5294; Endo, Y., Shibazaki, M., Nakamura, M., Takada, H., 1997 . Contrasting effects of lipopolysaccharides (endotoxins) from oral black-pigmented bacteria and Enterobacteriaceae on platelets, a major source of serotonin, and on histamine-forming enzyme in mice . J . Infect . Dis . 175, 1404-1412} . In the present study, it was found that such shock was almost completely prevented in those mice in which platelets were displaced from the blood by Cl2MBP-liposomes . These results suggest that in the spleen the depletion of phagocytic macrophages may impair the function or structure of this organ . This may lead to the entry of platelets into the spleen in such large numbers as to reduce their level in the blood and result in their prolonged accumulation in the spleen . The Cl2MBP-liposome may be an excellent tool for the in vivo investigation of the role of platelets, as well as that of macrophages.

Clin Diagn Lab Immunol, 1998 Jul, 5(4), 567 - 73
Development of a colony lift immunoassay to facilitate rapid detection and quantification of Escherichia coli O157:H7 from agar plates and filter monitor membranes; Ingram DT et al.; E . coli O157:H7 is a food-borne adulterant that can cause hemorrhagic ulcerative colitis and hemolytic uremic syndrome . Faced with an increasing risk of foods contaminated with E . coli O157:H7, food safety officials are seeking improved methods to detect and isolate E . coli O157:H7 in hazard analysis and critical control point systems in meat- and poultry-processing plants . A colony lift immunoassay was developed to facilitate the positive identification and quantification of E . coli O157:H7 by incorporating a simple colony lift enzyme-linked immunosorbent assay with filter monitors and traditional culture methods . Polyvinylidene difluoride (PVDF) membranes (Millipore, Bedford, Mass.) were prewet with methanol and were used to make replicates of every bacterial colony on agar plates or filter monitor membranes that were then reincubated for 15 to 18 h at 36 +/- 1 degree C, during which the colonies not only remained viable but were reestablished . The membranes were dried, blocked with blocking buffer (Kirkegaard and Perry Laboratories {KPL}, Gaithersburg, Md.), and exposed for 7 min to an affinity-purified horseradish peroxidase-labeled goat anti-E . coli O157 antibody (KPL) . The membranes were washed, exposed to a 3,3',5,5'-tetramethylbenzidine membrane substrate (TMB; KPL) or aminoethyl carbazole (AEC; Sigma Chemical Co., St . Louis, Mo.), rinsed in deionized water, and air dried . Colonies of E . coli O157:H7 were identified by either a blue (via TMB) or a red (via AEC) color reaction . The colored spots on the PVDF lift membrane were then matched to their respective parent colonies on the agar plates or filter monitor membranes . The colony lift immunoassay was tested with a wide range of genera in the family Enterobacteriaceae as well as different serotypes within the E . coli genus . The colony lift immunoassay provided a simple, rapid, and accurate method for confirming the presence of E . coli O157:H7 colonies isolated on filter monitors or spread plates by traditional culture methods . An advantage of using the colony lift immunoassay is the ability to test every colony serologically on an agar plate or filter monitor membrane simultaneously for the presence of the E . coli O157 antigen . This colony lift immunoassay has recently been successfully incorporated into a rapid-detection, isolation, and quantification system for E . coli O157:H7, developed in our laboratories for retail meat sampling.

J Mol Evol, 1998 Jul, 47(1), 52 - 61
Molecular characterization of the principal symbiotic bacteria of the weevil Sitophilus oryzae: a peculiar G + C content of an endocytobiotic DNA; Heddi A et al.; The principal intracellular symbiotic bacteria of the cereal weevil Sitophilus oryzae were characterized using the sequence of the 16S rDNA gene (rrs gene) and G + C content analysis . Polymerase chain reaction amplification with universal eubacterial primers of the rrs gene showed a single expected sequence of 1,501 bp . Comparison of this sequence with the available database sequences placed the intracellular bacteria of S . oryzae as members of the Enterobacteriaceae family, closely related to the free-living bacteria, Erwinia herbicola and Escherichia coli, and the endocytobiotic bacteria of the tsetse fly and aphids . Moreover, by high-performance liquid chromatography, we measured the genomic G + C content of the S . oryzae principal endocytobiotes (SOPE) as 54%, while the known genomic G + C content of most intracellular bacteria is about 39.5% . Furthermore, based on the third codon position G + C content and the rrs gene G + C content, we demonstrated that most intracellular bacteria except SOPE are A + T biased irrespective of their phylogenetic position . Finally, using the hsp60 gene sequence, the codon usage of SOPE was compared with that of two phylogenetically closely related bacteria: E . coli, a free-living bacterium, and Buchnera aphidicola, the intracellular symbiotic bacteria of aphids . Taken together, these results show a peculiar and distinctly different DNA composition of SOPE with respect to the other obligate intracellular bacteria, and, combined with biological and biochemical data, they elucidate the evolution of symbiosis in S . oryzae.

Ann Acad Med Singapore, 1998 Mar, 27(2), 223 - 6
Survey of aerobic bacterial infections in paediatric surgical intensive care unit patients; Yap KP et al.; Infections cause a significant amount of morbidity and mortality in paediatric surgical patients requiring intensive care . The study aims to describe the epidemiology of infection among these patients, to correlate the source of infection with the underlying medical condition, and to determine the antibiotic sensitivity pattern of the organisms . Through a retrospective review over a period of one year, 133 cases were analysed . The overall incidence of infection was 35% . Those who had emergency surgery had the highest infection rate (47%) . Respiratory tract infections were the commonest source of infection, and were associated with ventilator therapy rather than the underlying medical condition . The Enterobacteriaceae were the most common isolates seen . From antibiotic sensitivity tests, the empirical antibiotics of choice are gentamicin for suspected gram-negative infection and vancomycin for severe infections where methicillin-resistant Staphylococcus aureus is a likely cause . A high rate of resistance to ampicillin was seen and its use as a first-line monotherapy drug should be discontinued in our patient population.

Antimicrob Agents Chemother, 1998 Jul, 42(7), 1762 - 70
Bacterial pathogens isolated from patients with bloodstream infection: frequencies of occurrence and antimicrobial susceptibility patterns from the SENTRY antimicrobial surveillance program (United States and Canada, 1997); Pfaller MA et al.; The SENTRY Program was established in January 1997 to measure the predominant pathogens and antimicrobial resistance patterns of nosocomial and community-acquired infections over a broad network of sentinel hospitals in the United States (30 sites), Canada (8 sites), South America (10 sites), and Europe (24 sites) . During the first 6-month study period (January to June 1997), a total of 5,058 bloodstream infections (BSI) were reported by North American SENTRY participants (4,119 from the United States and 939 from Canada) . In both the United States and Canada, Staphylococcus aureus and Escherichia coli were the most common BSI isolates, followed by coagulase-negative staphylococci and enterococci . Klebsiella spp., Enterobacter spp., Pseudomonas aeruginosa, Streptococcus pneumoniae, and beta-hemolytic streptococci were also among the 10 most frequently reported species in both the United States and Canada . Although the rank orders of pathogens in the United States and Canada were similar, distinct differences were noted in the antimicrobial susceptibilities of several pathogens . Overall, U.S . isolates were considerably more resistant than those from Canada . The differences in the proportions of oxacillin-resistant S . aureus isolates (26.2 versus 2.7% for U.S . and Canadian isolates, respectively), vancomycin-resistant enterococcal isolates (17.7 versus 0% for U.S . and Canadian isolates, respectively), and ceftazidime-resistant Enterobacter sp . isolates (30.6 versus 6.2% for U.S . and Canadian isolates, respectively) dramatically emphasize the relative lack of specific antimicrobial resistance genes (mecA, vanA, and vanB) in the Canadian microbial population . Among U.S . isolates, resistance to oxacillin among staphylococci, to vancomycin among enterococci, to penicillin among pneumococci, and to ceftazidime among Enterobacter spp . was observed in both nosocomial and community-acquired pathogens, although in almost every instance the proportion of resistant strains was higher among nosocomial isolates . Antimicrobial resistance continues to increase, and ongoing surveillance of microbial pathogens and resistance profiles is essential on national and international scales.

J Clin Pathol, 1998 Apr, 51(4), 302 - 5
Experience of changing between signal and Bactec 9240 blood culture systems in a children's hospital; Gray J et al.; AIM: To compare experience of positive blood cultures in successive years before and after changing from Signal (Unipath) to Bactec 9240 (Becton Dickinson) blood culture systems . METHODS: Analysis of data collected prospectively on 7967 Signal and 7062 Bactec blood culture sets . RESULTS: Significant growths occurred in 5.7% of Signal and 8.9% of Bactec cultures; 33.0% more significant isolates and 24.0% more episodes of bacteraemia were detected in the second year, following introduction of the Bactec system . Inpatient hospital activity increased by 8.2% between the first and second years, although the numbers of blood cultures received actually fell by 11.4% . There were striking increases in numbers of isolates of coagulase negative staphylococci (47.7%) and Enterobacteriaceae (56.8%) from Bactec cultures . Two anaerobic bacteraemias were detected in Signal blood cultures, whereas none was detected by the Bactec system, despite 12.1% of sets including an anaerobic bottle . Of significant positive cultures, 90.2% were detected within one day with the Bactec 9240, compared with only 50.0% of Signal cultures; 20.7% of significant positive Signal blood cultures were detected only on terminal subculture . Microorganisms that were not significant were isolated from 5.1% Signal and 3.8% Bactec cultures . CONCLUSIONS: Compared with the Signal system, the Bactec 9240 offers markedly more rapid and sensitive detection of bacteraemia, together with a lower rate of non-significant isolates . However, using a single PEDS PLUS/F bottle the few episodes of anaerobic bacteraemia that occur in children are likely to be missed.

J Clin Microbiol, 1998 Jul, 36(7), 1953 - 8
Molecular epidemiology of Stenotrophomonas maltophilia isolated from clinical specimens from patients with cystic fibrosis and associated environmental samples; Denton M et al.; Stenotrophomonas maltophilia was isolated from the respiratory tracts of 41 (25%) of 163 children attending our pediatric cystic fibrosis unit between September 1993 and December 1995 . The extents of S . maltophilia contamination of environmental sites frequented by these patients were investigated with a selective medium incorporating vancomycin, imipenem, and amphotericin B . Eighty-two isolates of S . maltophilia were cultured from 67 different environmental sites sampled between January and July 1996 . The organism was widespread in the home environment, with 20 (36%) and 25 (42%) of sampled sites positive in the homes of colonized and noncolonized patients, respectively . In the nosocomial setting, it was isolated from 18 (32%) sites in the hospital ward and from 4 (17%) sites in the outpatient clinic area . The most common sites of contamination were sink drains, faucets, and other items frequently in contact with water . All environmental and clinical isolates were genotyped with enterobacterial repetitive intergenic consensus sequences as primers . A total of 33 of the 41 patients were colonized with unique strains, and four pairs of patients shared strains . Further characterization by pulsed-field gel electrophoresis after digestion with XbaI found that there was no evidence of patient-to-patient transmission; however, there was some evidence that a small number of patients may have acquired the organism from the hospital environment . Resampling of environmental sites in the hospital ward in January 1997 revealed evidence of genetic drift, complicating the accurate determination of environmental sources for clinical strains . The source of the majority of S . maltophilia strains colonizing the respiratory tracts of these patients with cystic fibrosis remained uncertain but may have represented multiple, independent acquisitions from a variety of environmental sites both within and outside the hospital.

J Clin Microbiol, 1998 Jul, 36(7), 1948 - 52
Evaluation of the VITEK 2 system for rapid identification of medically relevant gram-negative rods; Funke G et al.; The new VITEK 2 system (bioMerieux) was evaluated at two independent sites with the identification card for gram-negative bacilli (ID-GNB card) . Of the 845 strains tested, which represented 70 different taxa belonging to either the family Enterobacteriaceae or the nonenteric bacilli, 716 (84.7%) were correctly identified at the species level . Thirty-two (3.8%) additional strains were identified to the species level after the performance of simple, rapid manual tests (oxidase, hemolysis, indole reaction, motility, and pigmentation) . For 80 (9.5%) strains, these additional tests did not lead to an identification at the species level but the correct species identification was given among the organisms listed . Only 7 (0.8%) strains were misidentified, and 10 (1.2%) were not identified . Mistakes were randomly distributed over different taxa . Due to the new, more sensitive fluorescence-based technology of the VITEK 2 system, final results were available after 3 h . Since our evaluation was mainly a stress test, it is predicted that the VITEK 2 system in conjunction with the ID-GNB card would perform well under conditions of a routine clinical laboratory in identifying members of the family Enterobacteriaceae and selected species of nonenteric bacteria . This system is a promising, highly automated new tool for the rapid identification of gram-negative bacilli from human clinical specimens.

J Clin Microbiol, 1998 Jul, 36(7), 1846 - 52
Molecular epidemiological study of nosocomial Enterobacter aerogenes isolates in a Belgian hospital; Jalaluddin S et al.; In 1995, the rate of isolation of Enterobacter aerogenes in the Saint-Pierre University Hospital in Brussels, Belgium, was higher than that in the preceding years . A total of 45 nosocomial E . aerogenes strains were collected from 33 patients of different units during that year, and they were isolated from 19 respiratory specimens, 13 pus specimens, 7 blood specimens, 4 urinary specimens, 1 catheter specimen, and 1 heparin vial . The strains were analyzed to determine their epidemiological relatedness and were characterized by their antibiotic resistance pattern determination, plasmid profiling, and genomic fingerprinting by macrorestriction analysis with pulsed-field gel electrophoresis (PFGE) . The majority of the strains (82%) were multiply resistant to different commonly used antibiotics . Two major plasmid profiles were found: most strains (64%) harbored two plasmids of different sizes, whereas the others (20%) contained a single plasmid . PFGE with SpeI and/or XbaI restriction enzymes revealed that a single clone (80%) was responsible for causing infections or colonizations throughout the year, and this result was concordant with those obtained by plasmid profiling, with slight variations . By comparing the results of these three methods, PFGE and plasmid profiling were found to be the techniques best suited for investigating the epidemiological relatedness of E . aerogenes strains, and they are therefore proposed as useful tools for the investigation of nosocomial outbreaks caused by this organism.

J Formos Med Assoc, 1998 Jun, 97(6), 405 - 9
Bacteremia in patients with hematologic malignancies; Wang FD et al.; The decision regarding the appropriate empirical antibiotic therapy for bacteremia in patients with hematologic malignancies must be individualized in each institution, by taking into account variations in the patterns of microbial isolates and their resistance profiles . Microbial isolates and antibiotic resistance patterns must be taken into account at each hospital . A shift from bacteremia due to infections caused by predominantly gram-negative organisms to predominantly gram-positive organisms in patients with hematologic malignancies has been noted in reports from other countries . We investigated bacterial isolates and their antibiotic sensitivities in patients with hematologic malignancies in the Veterans General Hospital-Taipei . A total of 185 episodes of bacteremia in 140 patients with hematologic malignancies were recorded during the period from 1995 to 1996 . Unlike foreign reports, our investigation shows that gram-negative organisms still predominate, accounting for 72.7% of isolates, followed by gram-positive organisms, accounting for 26.3% of isolates, and anaerobes, accounting for 1% of isolates . Escherichia coli was the most commonly isolated organism, accounting for 23.9% of isolates, followed by Klebsiella pneumoniae (18.5%), Pseudomonas aeruginosa (12.2%), Enterobacter cloacae (7.3%), and methicillin-resistant Staphylococcus aureus (7.3%) . A high mortality rate was observed in gram-negative bacteremia: 31% for E . coli, 26% for K . pneumoniae, 24% for P . aeruginosa, and 33% for E . cloacae . If methicillin-resistant S . aureus bacteremia occurred, mortality was high (47%) . The antibiotic sensitivity profiles of the four most common gram-negative isolates (E . coli, K . pneumoniae, P . aeruginosa, and E . cloacae) indicated that, in our hospital, amikacin with either cefoperazone, ceftazidime, ciprofloxacin, or imipenem, would be an ideal combination for empirical therapy for bacteremia in patients with hematologic malignancies.

Br Poult Sci, 1998 May, 39(2), 229 - 34
Antimicrobial efficacy of AvGard carcase wash under industrial processing conditions; Coppen P et al.; 1 . The efficacy of the AvGard Trisodium Phosphate (TSP) immersion carcase wash process was evaluated during 5 industrial trials against Salmonella, Enterobacteriaceae, thermotolerant coliforms and total aerobic count . The effect against Pseudomonas was also studied in the first 3 trials . 2 . Dramatic reductions in Salmonella incidence were seen using a whole carcase rinse method . In 4 of the 5 trial sites, only one positive sample was found after AvGard treatment (average 0.5% incidence), in spite of an average control incidence of 57.7% . In the 5th site, a water-chilled broiler plant, an average control incidence of 74.0% was reduced to 9.4% after AvGard treatment . 3 . In the latter case, Most Probable Number (MPN) analyses were performed on some of the Salmonella positive samples taken from the control and post-treatment series; the average MPN count per carcase on controls was 115, whereas for AvGard treated birds the figure was only 0.6 per carcase, a greater than 2 log reduction . 4 . In addition, AvGard treatment gave average log reductions for all trials of: Enterobacteriaceae; 2.5 log; Coliforms; 2.7 log, and Total Aerobic Count; 1.1 log, leading to carcases substantially free of Gram negative pathogens . 5 . Pseudomonas was reduced by an average of 1.7 log in the first 3 trials, dramatically reducing the carcase loading of this important spoilage organism.

Appl Environ Microbiol, 1998 Jul, 64(7), 2449 - 53
Detection of hemolysin variants of Shiga toxin-producing Escherichia coli by PCR and culture on vancomycin-cefixime-cefsulodin blood agar; Lehmacher A et al.; The presence of a hemolysin-encoding gene, elyA or hlyA, from Shiga toxin-producing Escherichia coli (STEC) was detected by PCR in each of 95 strains tested . PCR products of elyA from human STEC isolates of serovars frequently detected in Germany, such as O157:H-, O103:H2, O103:H-, O26:H11, and O26:H-, showed nucleotide sequences identical to previously reported ones for O157:H7 and O111:H- strains . Compared to them, four elyA amplicons derived from human isolates of rare STEC serovars showed identity of about 98% but lacked an AluI restriction site . However, the nucleotide sequence of an amplicon derived from a porcine O138:K81:H- STEC strain was identical to the corresponding region of hlyA, encoding alpha-hemolysin, from E . coli . This hlyA amplicon showed 68% identity with the nucleotide sequence of the corresponding elyA fragment . It differed from the elyA PCR product in restriction fragments generated by AluI, EcoRI, and MluI . Of the 95 representative STEC strains, 88 produced hemolysin on blood agar supplemented with vancomycin (30 mg/liter), cefixime (20 micrograms/liter), and cefsulodin (3 mg/liter) (BVCC) . The lowest added numbers of two to six STEC CFU per g of stool or per ml of raw milk were detectable on BVCC plates after seeding of the preenrichment broth, modified tryptic soy broth (mTSB) supplemented with novobiocin (10 mg/liter), with 16 STEC strains . These strains represented the seven prevailing serovars diagnosed from German patients . However, with ground-beef samples, PCR was essential to identify the lowest added numbers of two to six STEC CFU among colonies of hemolyzing Enterobacteriaceae, such as Serratia spp . and alpha-hemolysin-producing E . coli . We conclude that preenrichment of stool and food samples in mTSB for 6 h followed by overnight culturing on BVCC is a simple method for the isolation and presumptive identification of STEC.

Scand J Plast Reconstr Surg Hand Surg, 1998 Jun, 32(2), 233 - 6
Mycotic aneurysm in a free flap; Kalainov DM et al.; A 41-year-old man developed a 3 x 4 cm wound after corrective osteotomies of his distal tibia and fibula . The wound was debrided and covered with a free gracilis muscle flap . Seven days after flap transfer, the arterial pedicle ruptured adjacent to the anastomosis . Attempted repair of the aneurysm failed and the graft was subsequently debrided . Intraoperative wound cultures grew Pseudomonas and Enterobacter cloacae, which were attributed to formation of the aneurysm.

Acta Haematol, 1998, 99(4), 206 - 11
Effect of discontinuing prophylaxis with norfloxacin in patients with hematologic malignancies and severe neutropenia . A matched case-control study of the effect on infectious morbidity; Martino R et al.; The use of fluorinated quinolones for prophylaxis of infections in neutropenic cancer patients has led to a reduction of infections with gram-negative enteric bacilli, but there is concern about the emergence of antibiotic-resistant entero-bacterial infections and a rise of gram-positive bacteremias . Due to these concerns, in mid-1995 the use of prophylactic norfloxacin was discontinued in our unit . In order to evaluate the impact of this measure on the infectious morbidity in our unit, 91 severe neutropenic episodes in 58 patients with hematologic malignancies who did not receive norfloxacin prophylaxis (NO group) were closely matched to 91 episodes in 60 patients who received norfloxacin prophylaxis (NORFLO group) . There were no differences in the incidence of febrile neutropenia, fever of unknown origin or bacteremia during the first febrile episode . There was a trend for a higher rate of coagulase-negative staphylococcal bacteremia in the NORFLO group (5 vs . 11 cases in the NO and NORFLO groups, respectively, p = NS) . Enterobacterial bloodstream infections were more frequent in the NO group (13 vs . 2 cases, respectively, p = 0.01), especially Escherichia coli (9 vs . 1 case, respectively, p = 0.01) . Twelve of 13 enterobacterial isolates in the NO group were sensitive to the fluoroquinolones vs . 0/2 in the NORFLO group (p = 0.07) . We conclude that the abrupt discontinuation of norfloxacin prophylaxis in our ward led to a rapid increase in the rate of fluoroquinolone-susceptible enterobacterial infections, with a scarce impact on infectious morbidity . This suggests that the selection of resistant flora in an inpatient ward by prophylactic antimicrobials may be reversible following the discontinuation of the prophylactic agent(s).

Biochim Biophys Acta, 1998 May 20, 1392(1), 51 - 8
Expression of an active phytoene synthase from Erwinia uredovora and biochemical properties of the enzyme; Neudert U et al.; The crtB gene encoding phytoene synthase from the carotenogenic enterobacterium Erwinia uredovora was overexpressed to about 20% of the total cellular protein in Escherichia coli . Formation of the active phytoene synthase had the effect of suppressing the growth of the expressing strain . Presumably inhibition of growth arose from the depletion of the substrate geranylgeranyl pyrophosphate (GGPP) which, in E . coli, is necessary for the synthesis of essential prenylpyrophosphate derivatives . In order to overcome the poor growth characteristics of the phytoene synthase expressing strain, GGPP levels were increased by co-expressing the isoprenoid biosynthetic genes crtE and idi, encoding the Erwinia GGPP synthase and Rhodobacter isopentenyl pyrophosphate isomerase, respectively . The crude enzyme preparation was partially purified 15-fold by chromatography on a DEAE column . A non-radioactive assay was developed that enabled the conversion of GGPP to phytoene . The reaction product was identified by co-chromatography with authentic standards on HPLC systems and comparison of spectral characteristics . The phytoene formed in vitro was present in both a 15-cis and all-trans isomeric configuration . The essential cofactors required were ATP in combinations with either Mn2+ or Mg2+ . The Km value for GGPP was determined as 41 microM . Phytoene synthesis was inhibited by phosphate ions and squalestatin . The I50 value for the latter inhibitor was 15 microM . Lineweaver-Burk plots showed constant Km values in the presence or absence of squalestatin .

Diagn Microbiol Infect Dis, 1998 Jun, 31(2), 389 - 95
Clinical strategies for serious infection: a North American perspective; Quinn JP; In the United States, as in Europe, clinical strategies for serious infection are being increasingly driven by growing numbers of cephalosporin-resistant and multiresistant gram-negative bacilli . In a survey of nearly 400 hospital intensive care units in North America, resistance rates of Klebsiella to third-generation cephalosporins increased (from 3.6 to 14.4%) between 1990 and 1993 . Resistance rates in Enterobacter are even higher, approaching 40% . Much of this resistance, which is due mainly to production of type-1 and extended spectrum beta-lactamases, appears to have arisen through overuse of third-generation cephalosporins and from poor hand-washing practices . In some American cities, a major reservoir of resistant organisms are nursing homes, where there is evidence of overuse of oral antibiotics . Currently, the most reliable agents available for the treatment of resistant gram-negative pathogens are the carbapenems, imipenem/cilastatin and meropenem, and the aminoglycoside, amikacin . A recent clinical study of meropenem monotherapy in patients with nosocomial pneumonia showed statistically significantly better clinical and microbiologic outcome compared with a standard regimen of ceftazidime plus tobramycin . The enhanced in vitro activity of meropenem against a number of key organisms may have been responsible for the superior results . Although the newer cephalosporins, cefepime and cefpirome, show greater stability to chromosomal type-1 beta-lactamases than ceftazidime, they have variable activity against extended spectrum beta-lactamase producers and can be rendered ineffective by permeability changes which occur in certain organisms . Carbapenems, on the other hand, possess good activity against virtually all of the pathogens which produce the clinically important beta-lactamases, and represent a reliable option for treatment.

Lett Appl Microbiol, 1998 Apr, 26(4), 253 - 8
Antimicrobial resistance of bacteria isolated from slaughtered and retail chickens in South Africa; Manie T et al.; Animal feed is increasingly being supplemented with antibiotics to decrease the risk of epidemics in animal husbandry . This practice could lead to the selection for antibiotic resistant micro-organisms . The aim of this study was to determine the level of antibiotic resistant bacteria present on retail and abattoir chicken . Staphylococci, Enterobacteriaceae, Salmonella and isolates from total aerobic plate count were tested for resistance to vancomycin, streptomycin, methicillin, tetracycline and gentamicin using the disc diffusion susceptibility test; resistance to penicillin was determined using oxacillin . Results from the antibiotic code profile indicated that many of the bacterial strains were displaying multiple antibiotic resistance (MAR) . A larger proportion of resistance to most antibiotics, except for vancomycin, was displayed by the abattoir samples, therefore suggesting that the incidence of MAR pathogenic bacteria was also higher in the abattoir samples . This resistance spectrum of abattoir samples is a result of farmers adding low doses of antibiotics to livestock feed to improve feeding efficiency so that the animals need less food to reach marketable weight . The lower incidence of MAR pathogenic bacteria in the retail samples is a result of resistance genes being lost due to lack of selective pressure, or to the fact that the resistant flora are being replaced by more sensitive flora during processing . The use of subtherapeutic levels of antibiotics for prophylaxis and as growth promoters remains a concern as the laws of evolution dictate that microbes will eventually develop resistance to practically any antibiotic . Selective pressure exerted by widespread antimicrobial use is therefore the driving force in the development of antibiotic resistance . This study indicated that a large proportion of the bacterial flora on fresh chicken is resistant to a variety of antibiotics, and that resultant food-related infections will be more difficult to treat.

Chest, 1998 Jun, 113(6), 1542 - 8
Infective exacerbations of chronic bronchitis: relation between bacteriologic etiology and lung function; Eller J et al.; STUDY OBJECTIVE: In patients with severe COPD, acute infective exacerbations are frequent . Streptococcus pneumoniae and Haemophilus influenzae are the most commonly isolated bacteria in sputum cultures from these patients . We hypothesized that in patients with advanced disease, Gram-negative bacteria other than H influenzae play at least an equally important role . METHODS: We evaluated clinical data and sputum culture results from 211 unselected COPD patients admitted to our hospital with an acute infective exacerbation of COPD . One hundred twelve patients fulfilled our protocol criteria of reliable microbiologic results and reproducible lung function tests; the patients were categorized according to the recently published three stages of severity . RESULTS: Lung function tests revealed an FEV1 of > or =50% of the predicted value in 30 patients (stage I), an FEV1 of 35% to <50% of the predicted value in 30 patients (stage II), and an FEV1 of < or =35% of the predicted value in 34 patients (stage III) . Bacteria were classified into three groups: group 1 contained S pneumoniae and other Gram-positive cocci; group 2, H influenzae and Moraxella catarrhalis; and group 3, Enterobacteriaceae and Pseudomonas spp . For all patients together, the most frequently isolated bacteria were group 3 organisms (Enterobacteriaceae and Pseudomonas spp, 48.2%), followed by group 1 organisms (S pneumoniae and other Gram-positive cocci, 30.4%), and group 2 organisms (H influenzae and M catarrhalis, 21.4%) . In stage I patients, 14 of 30 had bacteria from group 1, seven of 30 had group 2, and nine of 30 had group 3 . In stage II patients, eight of 30 had group 1 bacteria, 10 of 30 had group 2, and 12 of 30 had group 3 . In stage III patients, 12 of 52 had group 1 bacteria, seven of 52 had group 2, and 22 of 52 had group 3 . The three groups of bacteria causing infective exacerbations were unevenly distributed among the three severity stages of lung function (p=0.016) . CONCLUSION: There is a correlation between deterioration of lung function and the bacteria isolated from patients with infective exacerbations of COPD . In acute infective exacerbations, Enterobacteriaceae and Pseudomonas spp are the predominant bacteria in patients with an FEV1 < or =35% of the predicted value.

Protein Expr Purif, 1998 Jun, 13(1), 53 - 60
Overexpression, isotopic labeling, and spectral characterization of Enterobacter cloacae nitroreductase; Koder RL et al.; Bacterial nitroreductases have generated much interest recently due to their central roles in both nitroaromatic bioremediation and nitroaromatic toxicity, mutagenicity, and carcinogenicity . Enterobacter cloacae nitroreductase (NR) has been subcloned into the pET overexpression system and purified to homogeneity via a four-step procedure resulting in a final yield of 65.7 mg per liter . Overexpression in minimal media containing 15NH4Cl as the sole source of nitrogen yielded 37.6 mg per liter of homogenous NR containing > 99 atom % 15N . A series of melting curves generated under a variety of solvent conditions established the optimal conditions for NR stability as pH 7.5, low ionic strength phosphate buffer . A two-dimensional 1H-15N heteronuclear single quantum coherence nuclear magnetic resonance spectrum demonstrates this enzyme to be amenable to study by high-resolution multidimensional NMR in combination with amino-acid-specific isotopic labeling . Optical spectra of the purified enzyme suggest that the noncovalently bound flavin mononucleotide cofactor binds in a hydrophobic environment and is in the neutral and anionic protonation states in the oxidized and two-electron reduced oxidation states, respectively . NR exhibits a novel visible region circular dichroism spectrum which has a small distinct negative band at 366 nm and a large positive ellipticity at 454 nm with a shoulder centered at 480 nm.

Support Care Cancer, 1998 May, 6(3), 273 - 80
Prospective study of bacteraemia in cancer patients . Results of a French multicentre study; Escande MC et al.; We performed a prospective assessment of the current epidemiology of bacteraemia in cancer patients hospitalized in 70 different adult and paediatric haematology and oncology departments . Over a 1-month period, microbiologists from 54 hospitals collected clinical data relating to patients with at least one positive blood culture . In addition, all strains isolated were assessed for their in vitro susceptibility to three broad-spectrum cephalosporins suitable for empirical treatment in cancer patients: cefpirome, cefepime and ceftazidime . A total of 494 different strains were isolated from 1,038 blood cultures taken from 403 different patients . Seventeen strains were isolated from 13 patients with various nonmalignant diseases, and these cases were excluded from analysis . Overall, 330 (69.2%) of the strains were isolated in patients with haematological malignancy and 147 (30.8%), in patients with solid tumours . There was no difference in the distribution of the species involved in bacteraemia between patients with haematological malignancy and patients with solid tumours: coagulase-negative staphylococci were the leading pathogens (50.6% and 44.9%, respectively), followed by E . coli (11.2% and 12.2% respectively), S . aureus (6.3% vs 7.5%), streptococci (4.8% vs 5.4%) and P . aeruginosa (5.2% vs 4.8%) . All other species accounted for less than 5% in both groups . There was no difference in the strain distribution with age (> or = 15 years vs < 15 years) or type of underlying disease . S . aureus and Enterobacteriaceae bacteraemia were more frequent in patients with end-stage disease, while oral streptococci, Enterobacteriaceae and P . aeruginosa infections were more frequent in patients who were severely neutropenic . Digestive tract decontamination was associated with increased frequency of oral streptococci and decreased frequency of Enterobacteriaceae infections . All three cephalosporins demonstrated similar activity against E . coli, while cefpirome and cefepime appeared to be more effective against other Enterobacteriaceae . Ceftazidime had better activity against P . aeruginosa . Cefpirome was the most effective against Gram-positive cocci, especially oral streptococci and methicillin-susceptible staphylococci.

Biol Chem, 1998 Apr-May, 379(4-5), 437 - 41
Sequence comparison of the EcoHK31I and EaeI restriction-modification systems suggests an intergenic transfer of genetic material; Lee KF et al.; The genes coding for the EcoHK31I and EaeI restriction-modification (R-M) systems from Escherichia coli strain HK31 and Enterobacter aerogenes, respectively, have been cloned and sequenced . Both ENases recognize and cleave Y/GGCCR leaving 4 nucleotide 5'-protruding ends, while the MTases modify the internal cytosine . The systems were isolated on a 2.3kb AseI fragment for EcoHK31I, and a 4.6 kb HindIII fragment for EaeI . The R and M genes of both systems converge and overlap by 14 nucleotides . Previously, we found that M.EcoHK31I consisted of two subunits, (alpha and beta), with the beta subunit being translated from an alternative open reading frame within the gene encoding the alpha subunit . Sequence comparison between the EcoHK31I and EaeI systems reveals striking similarity . The eaeIM gene also encodes alpha and beta polypeptides of 309 and 176 amino acids which share 96% and 97% identity, respectively, with those of ecoHK31IM . ecoHK31IR and eaeIR encode proteins of 318 and 315 aa, respectively, which share 92% identity but are otherwise unique in the GenBank database . The EaeI and the EcoHK31I R-M systems were found to be flanked by genes coding for integrases . It is possible that these integrases have facilitated the transfer of this system among different bacterial species.

Antimicrob Agents Chemother, 1998 Jun, 42(6), 1370 - 4
Initial concentration-time profile of gentamicin determines efficacy against Enterobacter cloacae ATCC 13047; Rayner CR et al.; In vitro studies were designed to investigate the influence of peak drug concentration (Cmax), the area under the concentration-time curve (AUC), and, consequently, the trough concentration on the bactericidal effects of gentamicin against Enterobacter cloacae (MIC, 0.5 mg/liter) by simulating bolus versus infusion administration and bolus dosing with altered drug clearance . Bacteria in the lag phase were exposed to gentamicin concentration-time profiles modelling either bolus or infusion dosing (AUC constant, Cmax changing) with 30-min postdose peak concentrations (Cpeak30) of 4, 6, 8, and 10 mg/liter or bolus dosing with normal and double drug clearance (Cmax constant, AUC changing) corresponding to normal clearance profiles with Cpeak30 of 6 and 8 mg/liter . Exposure to gentamicin caused early bactericidal effects apparent by 2 h, followed by variable bacteriostatic and recovery phases . Exposure to bolus profiles resulted in greater bactericidal activity than the corresponding infusion profile up to a Cpeak30 of 8 mg/liter . At a Cpeak30 of 10 mg/liter, there were no differences in bactericidal effect . Double clearance profiles had a reduced bactericidal effect at 6 mg/liter compared to the corresponding normal clearance profile, but no differences in bactericidal effect were observed for 8-mg/liter double and normal clearance profiles . These results suggest that the initial exposure (i.e., 0 to 30 min) is a more important determinant for bacterial killing than the AUC or trough concentration for this bacterium . Subject to confirmation of these findings with other gram-negative bacteria, to optimize aminoglycoside efficacy the initial exposure (Cmax) should be maximized by giving higher doses or bolus administration at intervals which may not produce detectable trough concentrations . Clinical trials with a broad range of patients, especially those with higher clearance, would confirm these in vitro observations and define optimal dosing recommendations.

Antimicrob Agents Chemother, 1998 Jun, 42(6), 1350 - 4
beta-Lactamases responsible for resistance to expanded-spectrum cephalosporins in Klebsiella pneumoniae, Escherichia coli, and Proteus mirabilis isolates recovered in South Africa; Pitout JD et al.; Although resistance to the expanded-spectrum cephalosporins among members of the family Enterobacteriaceae lacking inducible beta-lactamases occurs virtually worldwide, little is known about this problem among isolates recovered in South Africa . Isolates of Klebsiella pneumoniae, Escherichia coli, and Proteus mirabilis resistant to expanded-spectrum cephalosporins recovered from patients in various parts of South Africa over a 3-month period were investigated for extended-spectrum beta-lactamase production . Antibiotic susceptibility was determined by standard disk diffusion and agar dilution procedures . Production of extended-spectrum beta-lactamases was evaluated by using the double-disk test, and the beta-lactamases were characterized by spectrophotometric hydrolysis assays and an isoelectric focusing overlay technique which simultaneously determined isoelectric points and general substrate or inhibitor characteristics . DNA amplification and sequencing were performed to confirm the identities of these enzymes . The P . mirabilis and E . coli isolates were found to produce TEM-26-type, SHV-2, and SHV-5 extended-spectrum beta-lactamases . An AmpC-related enzyme which had a pI of 8.0 and which conferred resistance to cefoxitin as well as the expanded-spectrum cephalosporins was found in a strain of K . pneumoniae . This is the first study which has identified organisms producing different extended-spectrum beta-lactamases from South Africa and the first report describing strains of P . mirabilis producing a TEM-26-type enzyme . The variety of extended-spectrum beta-lactamases found among members of the family Enterobacteriaceae isolated from major medical centers in South Africa is troubling and adds to the growing list of countries where these enzymes pose a serious problem for antimicrobial therapy.

J Biol Chem, 1998 Jun 5, 273(23), 14077 - 80
The vacB gene required for virulence in Shigella flexneri and Escherichia coli encodes the exoribonuclease RNase R; Cheng ZF et al.; vacB, a gene previously shown to be required for expression of virulence in Shigella and enteroinvasive Escherichia coli, has been found to encode the 3'-5' exoribonuclease, RNase R . Thus, cloning of E . coli vacB led to overexpression of RNase R activity, and partial deletion or interruption of the cloned gene abolished this overexpression . Interruption of the chromosomal copy of vacB eliminated endogenous RNase R activity; however, the absence of RNase R by itself had no effect on cell growth . In contrast, cells lacking both RNase R and polynucleotide phosphorylase were found to be inviable . These data indicate that RNase R participates in an essential cell function in addition to its role in virulence . The identification of the vacB gene product as RNase R should aid in understanding how the virulence phenotype in enterobacteria is expressed and regulated . On the basis of this information we propose that vacB be renamed rnr.

Glycobiology, 1998 Jun, 8(6), 557 - 67
Characterization of the lipid-carrier involved in the synthesis of enterobacterial common antigen (ECA) and identification of a novel phosphoglyceride in a mutant of Salmonella typhimurium defective in ECA synthesis; Rick PD et al.; The polysaccharide chains of enterobacterial common antigen (ECA) consist of linear trisaccharide repeat units with the structure -->3)-alpha-d-Fuc4NAc-(1-->4)-beta-d-ManNAcA-(1--> 4)-alpha-d-GlcNAc-(1-->, where Fuc4NAc is 4-acetamido-4, 6-dideoxy-d-galactose, ManNAcA is N -acetyl-d- mannosaminuronic acid, and GlcNAc is N -acetyl-d-glucosamine . The major form of ECA (ECAPG) consists of polysaccharide chains that are believed to be covalently linked to diacylglycerol through phosphodiester linkage; the phospholipid moiety functions to anchor molecules in the outer membrane . The ECA trisaccharide repeat unit is assembled as a polyisoprenyl-linked intermediate which has been tentatively identified as Fuc4NAc-ManNAcA-GlcNAc-pyrophosphorylundecaprenol (lipid III) . Subsequent chain-elongation presumably occurs by a block-polymerization mechanism . However, the identity of the polyisoprenoid carrier-lipid has not been established . Accordingly, the current studies were conducted in an effort to structurally characterize the polyisoprenyl lipid-carrier involved in ECA synthesis . Isolation and characterization of the lipid carrier was facilitated by the accumulation of a ManNAcA-GlcNAc-pyrophosphorylpolyisoprenyl lipid (lipid II) in mutants of Salmonella typhimurium defective in the synthesis of TDP-Fuc4NAc, the donor of Fuc4NAc residues for ECA synthesis . Analyses of lipid II preparations by fast atom bombardment tandem mass spectroscopy (FAB-MS/MS) resulted in the identification of the lipid-carrier as the 55-carbon polyisoprenyl alcohol, undecaprenol . These analyses also resulted in the identification of a novel glycolipid which copurified with lipid II . FAB-MS/MS analyses of this glycolipid revealed its structure to be 1,2-diacyl- sn -glycero-3-pryophosphoryl-GlcNAc-ManNAcA (DGP-disaccharide) . An examination of purified ECAPGby phosphorus-31 nuclear magnetic resonance spectroscopy confirmed that the polysaccharide chains are linked to diacylglycerol through phosphodiester linkage . Thus, DGP-disaccharide does not appear to be an intermediate in ECAPGsynthesis . Nevertheless, although the available evidence clearly indicate that lipid II is a precursor of DGP-disaccharide, the function of this novel glycolipid is not yet known, and it may be an intermediate in the biosynthesis of a molecule other than ECAPG.

Biochem J, 1998 Apr 15, 331 ( Pt 2), 639 - 48
Cystathionine gamma-synthase from Arabidopsis thaliana: purification and biochemical characterization of the recombinant enzyme overexpressed in Escherichia coli; Ravanel S et al.; Cystathionine gamma-synthase catalyses the first reaction specific for methionine biosynthesis in plants, the gamma-replacement of the phosphoryl substituent of O-phosphohomoserine by cysteine . A cDNA encoding cystathionine gamma-synthase from Arabidopsis thaliana has been cloned and used to overexpress the enzyme in Escherichia coli . The native recombinant enzyme is a homotetramer composed of 53 kDa subunits, each being tightly associated with one molecule of pyridoxal 5'-phosphate that binds at lysine-379 of the protein precursor . The replacement reaction follows a Ping Pong mechanism with a Vmax of 33.6 units/mg and Km values of 2.5 mM and 460 microM for O-phosphohomoserine and cysteine respectively . The protective effect of O-phosphohomoserine against enzyme inactivation by propargylglycine indicated that the Kd for the substrate is approx . 1/2500 of its Km value . Thus most of these biochemical properties are similar to those previously reported for plant and bacterial cystathionine gamma-synthases . However, the plant enzyme differs markedly from its enterobacterial counterparts because it catalyses a very faint gamma-elimination of O-phosphohomoserine in the absence of cysteine, this process being about 1/2700 as fast as the gamma-replacement reaction and approx . 1/1500 as fast as the gamma-elimination catalysed by the E . coli enzyme . This huge difference could be attributed to the inability of the A . thaliana cystathionine gamma-synthase to accumulate a long-wavelength-absorbing species that is characteristic for the efficient gamma-elimination reaction catalysed by the enterobacterial enzyme.

Comput Methods Programs Biomed, 1998 Apr, 56(1), 11 - 22
Stochastic complexity as a taxonomic tool; Gyllenberg HG et al.; In this paper we propose a method of constructing a hierarchical classification based on the notion of stochastic complexity . Minimization of stochastic complexity amounts to maximization of the information content of the classification . A dendrogram is obtained by first finding the classification which minimizes stochastic complexity and then by step-wise merging of groups such that at each step there is a minimum loss of information . The method was applied to a database containing 5313 strains of Enterobacteriaceae . The results are in reasonable accordance with present-day views on the taxonomy of Enterobacteriaceae.

J Med Entomol, 1998 May, 35(3), 222 - 6
Midgut bacteria in Anopheles gambiae and An . funestus (Diptera: Culicidae) from Kenya and Mali; Straif SC et al.; Field studies in Kenya and Mali investigated the prevalence of bacteria in the midguts of malaria vectors, and the potential relationship between gram-negative bacteria species and Plasmodium falciparum sporozoites . Midguts were dissected from 2,430 mosquitoes: 863 Anopheles funestus Giles and 1,037 An . gambiae s.l . Giles from Kenya, and 530 An . gambiae s.l . from Mali . An . funestus had a higher prevalence of gram-negative bacteria (28.5%) compared with An . gambiae collected in Kenya and Mali (15.4 and 12.5%, respectively) . Twenty different genera of bacteria were identified by gas chromatography from 73 bacterial isolates from mosquito midguts . Pantoea agglomerans (Enterobacter agglomerans) was the most common species identified . There was no association between gram-negative bacteria in the midgut and P . falciparum sporozoites in field-collected An . gambiae s.l . and An . funestus . However, An . funestus females that harbored gram positive bacteria were more likely to be infected with sporozoites compared with those with no cultivable bacteria or gram negative bacteria in their midguts . Habitat-related variation in the prevalence of diverse types of bacteria in mosquitoes could influence malaria parasite development in mosquitoes and corresponding sporozoite prevalence.

Klin Khir . 1997;(11-12):64.
{Characteristics of peritoneal exudate microflora in children with appendicular peritonitis}; Bodnar BM; Bacteriological investigation of peritoneal exudate was conducted in 131 children with peritonitis . The greatest quantity of pathogenic and conventionally pathogenic Escherichias and bacteroids was revealed in March, April and September . In summer peritonitis was caused by pathogenic and conventionally pathogenic Escherichias in association with enterobacterias, staphylococci and other microorganisms.

Ann Trop Med Parasitol, 1998 Jan, 92(1), 107 - 13
Tungiasis among five communities in south-western Trinidad, West Indies; Chadee DD; The prevalences of Tunga penetrans Linn . within the five townships of Granville, Fullerton, Icacos, Coromandel and Cedros in south-western Trinidad, West Indies, as determined by physical examination of all inhabitants present during the survey, were 17.0% (38/223 subjects), 15.7% (36/237), 31.4% (102/325), 17.4% (42/242) and 17.9% (50/280), respectively . The rate in Icacos was significantly higher than in the other four sites (P < 0.001) . Not only were males more likely to be infected than females in all five study sites (P < 0.0007) but chigoe-flea burdens were also higher in males than in females (P < 0.012), with mean (S.D.) burdens of 5.44 (2.54) fleas/male infected subject and 2.38 (2.00) fleas/female infected subject . Feet were significantly more infected than other areas of the body (P < 0.001) . Analysis of variance revealed that the interactions between prevalence of chigoe-flea infection and geographical location (P = 0.0058) and between sex of infected subject and site of infection (P = 0.0109) were highly significant but that between geographical location and sex of infected subject was not significant (P > 0.30) . At least seven species of bacteria, with varying sensitivities to antibiotics, were isolated from 16 patients with sepsis associated with their T . penetrans infections: Streptococcus pyogenes, beta-haemolytic Streptococcus (not group A), Klebsiella aerogenes, Enterobacter agglomerans, Staphylococcus aureus, Escherichia coli and a Bacillus species . Closteridium tetani was not isolated.

Arch Immunol Ther Exp (Warsz), 1998, 46(2), 79 - 83
Serum IgG antibodies in children and adults reacting with Helicobacter pylori lipopolysaccharides; Cedzynski M et al.; The presence of IgG antibodies reacting with Helicobacter pylori lipopolysaccharides (LPSs) in sera from children and adults diagnosed as H . pylori-infected, as well as healthy persons, was tested . There was no correlation between the production of antibodies reacting with H . pylori surface proteins and LPSs . Also no correlation between reactivity of tested sera with H . pylori antigens and deep rough mutant (Re types) enterobacterial LPSs was revealed . The prevalence of anti-LPS IgG in randomly selected children was relatively high.

Epidemiol Mikrobiol Imunol, 1998 Apr, 47(2), 43 - 6
{Antibacterial activity of lactobacilli}; Dembele T et al.; The antagonistic action of lactobacilli is an important factor in the protection of the vagina of fertile women from infection by other microorganisms . In the present study the authors investigated 17 strains of lactobacilli, incl . 11 of vaginal origin . The objective was to investigate in more detail the antibacterial activity of lactobacilli and to attempt to assess substances responsible for inhibition . The investigated lactobacilli inhibited some strains of Escherichia coli, Serratia marcescens, Shigella boydii, Staphylococcus aureus, Listeria monocytogenes, Listeria innocua and Listeria ivanovii with different intensity . The authors provided evidence that inhibition is due mainly to organic acids and to a lesser extent to bacteriocins . The authors assessed also the effect of enterobacteria on lactobacilli but did not observe any inhibition of lactobacilli.

Microbiology, 1998 May, 144 ( Pt 5), 1435 - 41
Aspartate carbamoyltransferase from a psychrophilic deep-sea bacterium, Vibrio strain 2693: properties of the enzyme, genetic organization and synthesis in Escherichia coli; Xu Y et al.; The aspartate carbamoyltransferase (ATCase) genes of psychrophilic Vibrio strain 2693 were cloned by complementation in Escherichia coli and the enzyme was partly characterized . The genes constitute a pyrBI operon homologous to the cognate structure in E . coli where pyrB and pyrI respectively encode the catalytic and the regulatory chains of ATCase . The strong sequence similarities noted between Vibrio and E . coli ATCases include extensive conservation of residues involved in interactions between subunits, suggesting that the two enzymes have very similar tertiary and quaternary structures . Vibrio ATCase is, however, not activated by ATP and not synergistically inhibited by CTP and UTP . It is also much more thermolabile than E . coli ATCase . With respect to Pyrococcus abyssi and E . coli ATCases, Vibrio ATCase presents marked differences in composition which could be related to its psychrophilic character . The results of these structural and functional comparisons indicate that Vibrio 2693 ATCase is a suitable model for biochemical studies on structure-function relationships in a 'cold' allosteric enzyme . The operon is expressed from a promoter which is immediately followed by a pyrimidine-rich leader ORF terminating within a putative transcription attenuator . These genetic and enzymic data strengthen the evolutionary relationship already noted between Vibrionaceae and Enterobacteriaceae.

Aviakosm Ekolog Med, 1998, 32(1), 73 - 7
{Influence of lactobacterin on the upper respiratory tract microflora of subjects with microflora disorders}; Korniushenkova IN; High respiratory tract microflora recovery has been revealed in human subjects treated perorally with commercial Lactobacterinum . In most of the participants in the study, different (up to epidemically significant) values of disbiotic shifts including persistence of conventional pathogens (enterobacteria) and pathogenic staphylococci in high respiratory tract mucosa as well as nasopharyngeal lactoflora deficiency were observed in the pretreatment period . Significant, in the order of one to four, decreases in pathogenic microflora count up to complete elimination were accompanied by lactoflora restoration in a part of the subjects after treatment . Hence, Lactobacterinum seems to be a perspective means for correcting and optimizing the high respiratory tract microflora, especially in contingents subjected to the environmental factors with a high risk of disbiotic disorders.

J Chemother, 1998 Apr, 10(2), 102 - 7
Susceptibility to new beta-lactams of enterobacterial extended-spectrum beta-lactamase (ESBL) producers and penicillin-resistant Streptococcus pneumoniae in Mexico; Silva J et al.; The activities of several beta-lactam antimicrobial agents, aminoglycosides and ciprofloxacin, were determined against 62 clinical isolates of enterobacteria resistant to oxyimino cephalosporins (extended-spectrum beta-lactamase producers), collected during 1991 to 1993, and 16 penicillin-resistant invasive isolates of Streptococcus pneumoniae collected during 1994-1996 . The numbers and percentages of susceptible enterobacterial strains to tested antibiotics were: imipenem 60 (97%), ciprofloxacin 57 (92%), cefepime 56 (90%), cefpirome 34 (55%), aztreonam 13 (21%), cefotaxime 7 (11%), ceftazidime 0 (0%), amikacin 11 (18%) and gentamicin 16 (26%) . Despite the fact that these strains had never been exposed previously to cefepime or cefpirome, the susceptibility was 90% and 55%, respectively . No penicillin-resistant strains of S . pneumoniae were susceptible to cefotaxime, imipenem or cefepime . Only one strain was susceptible to ceftazidime and 4 (25%) were susceptible to cefpirome . Erythromycin showed the greatest activity with 12 (75%) susceptible strains.

Infect Immun, 1998 Jun, 66(6), 2887 - 94
Characterization of the type 3 fimbrial adhesins of Klebsiella strains; Sebghati TA et al.; The Klebsiella pneumoniae fimbrial adhesin, MrkD, mediates adherence to the basolateral surfaces of renal and pulmonary epithelia and to the basement membranes of tissues . Although all isolates possessing the MrkD adhesin mediate the agglutination, in vitro, of erythrocytes treated with tannic acid, the mrkD gene is not conserved within species . The ability of a plasmid-borne mrkD gene product to mediate binding to type V collagen is associated frequently with strains of K . oxytoca and rarely with strains of K . pneumoniae . In K . pneumoniae, the MrkD adhesin is located within a chromosomally borne gene cluster and mediates binding to collagen types IV and V . The plasmid-borne determinant, mrkD1P, and the chromosomally borne gene, mrkD1C, are not genetically related . Some strains of enterobacteria possess a mrkD1C allele that is associated with hemagglutinating activity but does not bind to either type IV or type V collagen.

Ann Plast Surg, 1998 May, 40(5), 523 - 7
Vascularized muscle flaps and reoperative approach for complicated, dehisced sternal wounds in children; Sung K et al.; Vascularized muscle flaps for treatment of mediastinitis and sternal wound dehiscence have become standard treatment practice, but triple-muscle flap reconstruction is reserved for the more complex wounds . The incisional approach for reoperation in such patients is controversial . We report an extremely ill infant, born at 38 weeks gestational age, who underwent an arterial switch procedure for transposition of the great arteries at 12 days of age . Sternal wound infection, dehiscence, mediastinitis, and extensive wound necrosis complicated the postoperative course . The cultured organism Enterobacter is a relatively rare cause for median sternotomy wound infection and was associated with massive postoperative hemorrhage . The infant underwent multiple debridements and at 2 months of age had reconstructive surgery with bilateral pectoralis major muscle advancement flaps combined with a rectus abdominis muscle flap . Three months postreconstruction the infant required reoperation to correct a stenosis at the site of the pulmonary artery anastomosis . This surgery was carried out through the previous median sternotomy scar because it was the safest, most direct approach and would also limit additional scarring . Long-term follow-up at 2 years of age shows a well-developed young boy with no limitations in growth and activity.

J Am Mosq Control Assoc, 1998 Mar, 14(1), 72 - 7
Bacterial density and survey of cultivable heterotrophs in the surface water of a freshwater marsh habitat of Anopheles quadrimaculatus larvae (Diptera: Culicidae); Smith TW et al.; We examined surface water samples collected in September and October 1994 from a freshwater marsh habitat containing larval Anopheles quadrimaculatus mosquitoes . Bacterial densities in direct microscopic counts ranged from 9.7 x 10(5) to 1.3 x 10(7) cells/ml . Densities of cultivable bacteria on trypticase soy agar medium ranged from 1.0 to 1.5 x 10(5) cells/ml . The majority of 888 isolates were gram-positive rods (41%) followed by gram-negative rods (28%) . Analysis of the cellular fatty acid profiles of 824 isolates using gas chromatography and Microbial Identification Systems TSBA (Rev . 3.60) library software grouped the bacteria into Bacillus spp . (35%), other gram-positive bacteria (16%), pseudomonads (15%), other gram-negative bacteria including mainly Enterobacteriaceae and Vibrionaceae (21%), and profiles not recognized (13%) . Among 33 genera within these groups, the most common were Bacillus, Pseudomonas, Aeromonas, and Arthrobacter.

J Antimicrob Chemother, 1998 Apr, 41(4), 443 - 50
Comparative in-vitro activity of cefpirome against isolates from intensive care and haematology/oncology units . Belgian Multicentre Study Group; Pierard D et al.; The susceptibility of 389 Enterobacteriaceae, 231 other Gram-negative bacilli (including 150 Pseudomonas aeruginosa) and 233 Gram-positive organisms was determined by the NCCLS reference microdilution technique against cefpirome and other antibiotics . Cefpirome and cefepime were the most active compounds against Enterobacteriaceae, including potentially beta-lactamase-inducible species . The MIC90 of cefpirome against potentially inducible and non-inducible species of Enterobacteriaceae was 2 mg/L and 0.5 mg/L, respectively . Ceftazidime, cefpirome and cefepime had similar activity against P . aeruginosa, with MIC90s of 64 mg/L, 64 mg/L and 32 mg/L, respectively . Cefpirome and cefepime had similar activity against Gram-positive cocci, with MIC90s of 1 mg/L and 2 mg/L, respectively, against oxacillin-susceptible Staphylococcus aureus and 64 mg/L and 128 mg/L, respectively, against Enterococcus spp.; both had an MIC90 of 1 mg/L against Streptococcus pneumoniae . This study shows that fourth-generation cephalosporins, such as cefpirome, could be useful in haematology/oncology units and, in particular, ICUs where high resistance rates are observed.

Clin Infect Dis, 1998 May, 26(5), 1066 - 70
Epidemiology of severe hospital-acquired infections in patients with liver cirrhosis: effect of long-term administration of norfloxacin; Campillo B et al.; We performed a 5-year retrospective study to evaluate the effect of long-term administration of norfloxacin on the epidemiology of severe hospital-acquired infections in patients with advanced cirrhosis . Sixty-seven episodes of spontaneous bacterial peritonitis and 60 episodes of bacteremia occurred in, respectively, 46 patients (group 1a) and 52 patients (group 1b) who did not receive norfloxacin, while 23 and 17 episodes occurred in 21 patients (group 2a) and 17 patients (group 2b) during or within 10 days after long-term administration of norfloxacin . Enterobacteriaceae were more prevalent in groups 1a and 1b than in the other two groups (P < .001 and P < .01, respectively); conversely, staphylococci were more prevalent in groups 2a and 2b (P < .001 and P < .05, respectively) . The rate of staphylococcal resistance to methicillin was 53.6% in groups 1a and 1b and 77.3% in groups 2a and 2b . We conclude that long-term norfloxacin administration to cirrhotic patients reduces the risk of gram-negative infections but increases the risk of severe hospital-acquired staphylococcal infections and of high-level resistance to antibiotics.

J Med Chem, 1998 Apr 23, 41(9), 1507 - 12
Therapeutic effects of monoclonal antibody-beta-lactamase conjugates in combination with a nitrogen mustard anticancer prodrug in models of human renal cell carcinoma; Svensson HP et al.; A panel of 13 renal cell carcinoma cell lines was evaluated for the expression of antigens recognized by the L6 and L49 monoclonal antibodies . All of the cell lines were strongly positive for the L6 antigen, and 9/13 bound 96.5, which, like the L49 monoclonal antibody, recognizes the p97 melanotransferrin antigen . The L6 and L49 antibodies were chemically conjugated to Enterobacter cloacae beta-lactamase (bL), and their abilities to effect site-selective anticancer prodrug activation on two of the renal cell carcinoma cell lines (SN12P and 1934J) were evaluated in vitro and in vivo . L49-bL was 10-90-fold more potent in vitro than L6-bL for the activation of 7-(4-carboxybutanamido)cephalosporin mustard (CCM), a cephalosporin prodrug of phenylenediamine mustard (PDM) . In addition, L49-bL showed higher degrees of specific SN12P and 1934J intratumoral uptake than L6-bL, even though the expression of L6 antigen was 2-fold higher than that of p97 . These differences might be due to the high-affinity antigen binding of L49-bL relative to L6-bL . In vivo studies utilizing nude mice with established subcutaneous SN12P and 1934J tumor xenografts demonstrated that L49-bL/CCM combinations led to regressions and cures at well-tolerated doses, while L6-bL/CCM and the nonbinding control conjugate P1.17-bL in combination with CCM were ineffective . Conjugate localization in 1934J tumors was much lower than that observed in SN12P tumors, a finding that might acount for the higher activities of L49-bL/CCM in the latter model . These data show that the p97 antigen on renal cell carcinomas can be exploited for selective prodrug activation, even on tumors that localize very small amounts of the L49-bL conjugate.

Antimicrob Agents Chemother, 1998 May, 42(5), 1233 - 8
Meropenem versus cefuroxime plus gentamicin for treatment of serious infections in elderly patients; Jaspers CA et al.; In this multicenter study, the efficacy of and tolerability for meropenem were compared with those for the combination of cefuroxime-gentamicin (+/- metronidazole) for the treatment of serious bacterial infections in patients > or = 65 years of age . A total of 79 patients were randomized; thirty-nine received meropenem (1 g/8 h), and 40 received cefuroxime (1.5 g/8 h) plus gentamicin (4 mg/kg of body weight daily) for 5 to 10 days . Metronidazole (500 mg/6 h) could be added to the cefuroxime-gentamicin regimen for the treatment of intra-abdominal infections (n = 10) . Seventy patients were evaluable for clinical efficacy; the primary diagnoses were as follows: pneumonia in 41 patients (20 treated with meropenem, 21 treated with cefuroxime-gentamicin), intra-abdominal infection in 10 patients (7 meropenem, 3 cefuroxime-gentamicin-metronidazole), urinary tract infection (UTI) in 11 patients (6 meropenem, 5 cefuroxime-gentamicin), sepsis syndrome in 7 patients (4 meropenem, 3 cefuroxime-gentamicin), and "other" in 1 patient (cefuroxime-gentamicin) . The pathogens isolated from 18 patients with bacteremia were as follows: Staphylococcus spp . (n = 2), Streptococcus spp . (n = 2), members of the family Enterobacteriaceae (n = 11), and Bacteroides spp . (n = 3) . A satisfactory clinical response at the end of therapy was achieved in 26 of 37 (70%) and 24 of 33 (73%) evaluable patients treated with meropenem and combination therapy, respectively . Clinical success was achieved in 23 of 31 (74%) and 21 of 28 (75%) evaluable patients with infections other than UTIs, respectively . A satisfactory microbiological response occurred in 15 of 22 (68%) patients in the meropenem group compared with 12 of 19 (63%) treated with combination therapy . Renal failure occurred during therapy in 2 of 39 (5%) meropenem recipients compared with 5 of 40 (13%) of those treated with combination therapy . The findings in this small study indicate that meropenem is as efficacious for and as well tolerated by elderly patients as the combination of cefuroxime-gentamicin (+/- metronidazole).

Electrophoresis, 1998 Apr, 19(4), 545 - 50
Structural and functional implications of sequence diversity of Pseudomonas aeruginosa genes oriC, ampC and fliC; Spangenberg C et al.; Sequence analysis of three representative gene loci, oriC, ampC and fliC, in 19 Pseudomonas aeruginosa strains revealed a low sequence diversity that does not correlate with the extensive diversity of P . aeruginosa habitats . Single point mutations lead to a mean sequence diversity of 0.40%, 0.38% and 0.59% for oriC, ampC and a-type fliC, respectively, but of only 0.05% for b-type flagellin genes . The analyzed genes encode highly conserved functions that are subject to strong selective pressure . The detected nucleotide substitutions of oriC, accumulating in a central 95 bp region, affect neither the putative DnaA binding sites nor the 13 bp direct repeats that presumably provide the sites to open oriC duplex DNA . Even in P . aeruginosa strain DSM 1128, which exhibits an unusually high sequence variability in several analyzed genes, the 9 bp and 13 bp motifs are conserved, reflecting their essential functional role in replication initiation . The two flagellin types, differing by 37-38% in their primary structure, exhibit pronounced structural and functional homology, as shown by alignment of flagellin variants by hydrophobicity index, probability of surface exposure, chain flexibility and antigenicity, and by cross-reactivity between both proteins using specific antisera . Five nonsynonymous nucleotide substitutions of ampC lead to beta-lactamase variants that differ in recognition and turnover of substrate, as deduced from the three-dimensional structure of the highly homologous Enterobacter cloacae beta-lactamase and confirmed by inhibition kinetics . The identified point mutations in the three genes are classified as selectively equivalent sequence variants indicating neutral genetic drift as a mechanism of molecular evolution in P . aeruginosa, rather than positive selection.

Enferm Infecc Microbiol Clin, 1998 Feb, 16(2), 79 - 82
{The etiology of nosocomial infection in surgery: comparison of 2 years (1988 and 1996)}; Valero LF et al.; BACKGROUND: Nosocomial infections (NI) make up an important problem in Public Health Care . From an etiologic point of view they are characterized by their constant evolution over time . Thus, the aim of this study was to know the etiologic variations of NI in the surgery departments of a university hospital . MATERIAL AND METHODS: Active surveillance of NI in the departments of general, vascular and urologic surgery was undertaken in 1988 and 1996 . The frequency of the presentation of different microorganisms was globally calculated and based on the localization of the infection . RESULTS: At present, the most important microorganisms were E . coli (20.6%), Enterococcus sp . (15.6%), S . epidermidis (8.8%), Streptococcus sp . (8.5%), other negative coagulase staphylococci (NCS) (5.7%), Pseudomonas sp . (5.5%), S . aureus (5.2%), and Candida sp . (4.3%) . On analysis of the temporal evolution an increase was observed in gram positives (27.4% in 1988 and 46.4% in 1996) . Enterococcus sp . increased in surgical infections (5.8% in 1988 and 15.8% in 1996) and in the urinary tract (8.5% in 1988 and 25.6% in 1996) . Contrary to the S . epidermidis, the NCS increased in importance mainly in infections at the site of surgery (0% in 1988 to 5.1% in 1996) . The appearance of Klebsiella sp., Enterobacter sp . and Proteus sp . decreased . CONCLUSIONS: A great variation was observed in the etiology of nosocomial infections in surgery departments not only over time but also based on the localization of the infection . In recent years gram positive infections have increased with a rise in the incidence of staphylococci, streptococci and enterococci, in addition to greater protagonism by Candida sp.

Mayo Clin Proc, 1998 May, 73(5), 473 - 8
Bacterial and parasitic cholangitis; Carpenter HA; Bacterial cholangitis is a clinically defined syndrome caused by the regurgitation of infected bile into the circulation . The pathogenic mechanism is unclear, and systemic sepsis may not occur . Prerequisite conditions are the presence of microorganisms in the bile and increased biliary pressure . Bacteria that commonly cause cholangitis are Escherichia coli, Klebsiella, Enterococcus, Enterobacter, Pseudomonas, and anaerobes . Although most infections are polymicrobial, this situation may not always prevail . Successful treatment depends on relieving biliary obstruction and administering antibiotics effective against bacteria in the circulation and the bile . The causes of biliary obstruction that predispose to bacterial cholangitis are myriad . Common conditions include biliary stones and benign strictures . In many parts of the world, biliary parasites are an important factor . Biliary parasites cause necrosis, inflammation, fibrosis, strictures, and cholangiectasis of the bile ducts by several mechanisms: (1) as a direct result of the irritating chemical composition of the parasite, parasitic secretions, or eggs; (2) physical obstruction of the bile ducts; (3) induction of formation of biliary stones; and (4) introduction of bacteria into the biliary system during migration from the duodenum . Therefore, bacterial cholangitis has an important and frequently dominant role in the pathogenesis and clinical course of biliary disease due to these parasitic infestations . Common biliary parasites include the nematode Ascaris lumbricoides, the trematodes Opisthorchis viverrini and felineus, Clonorchis sinensis, and Fasciola hepatica, and the cestodes Echinococcus granulosus and multilocularis . The epidemiologic, pathologic, and clinical manifestations of these parasitic infestations are reviewed.

Berl Munch Tierarztl Wochenschr, 1998 Apr, 111(4), 127 - 33
{Generation and characterization of avian vitelline antibodies against lipopolysaccharide and lipid A . 2 . Investigations of specificity of egg yolk antibodies (IgY) against endotoxin}; Sasse M et al.; Various preparations of egg yolk antibodies against different endotoxins of gram-negative bacteria were characterized with regard to their immunological properties . To do this, we investigated the reactivity of antibodies against a number of lipopolysaccharides and lipid-A by enzyme-immuno-assays and immunoblot . It could be shown that all antibody preparations contained specific antibodies, reactive with their homologous antigen . Furthermore these antibodies showed cross-reactivity with structural diverse LPS- and lipid A-antigens from different sources . Anti lipid A-antibodies appeared to be highly crossreactive with purified LPS and lipid A from several gram-negative organisms . Egg yolk antibodies raised by immunization with LPS showed cross-reactivity with enterobacterial LPS and only marginal reactivity with both LPS from other gram-negative bacteria and lipid A . The results from immunoblot experiments confirmed our findings from EIA-studies.

J Antimicrob Chemother, 1998 Mar, 41(3), 367 - 72
Cefepime and amikacin synergy in vitro and in vivo against a ceftazidime-resistant strain of Enterobacter cloacae; Mimoz O et al.; The activities of cefepime and amikacin alone or in combination against an isogenic pair of Enterobacter cloacae strains (wild type and stably derepressed, ceftazidime-resistant mutant) were compared using an experimental model of pneumonia in non-leucopenic rats . Animals were infected by administering 8.4 log10 cfu of E . cloacae intratracheally, and therapy was initiated 12 h later . At that time, the animals' lungs showed bilateral pneumonia and contained more than 7 log10 E . cloacae cfu/g tissue . Because rats eliminate amikacin and cefepime much more rapidly than humans, renal impairment was induced in all animals to simulate the pharmacokinetic parameters of humans . In-vitro susceptibilities showed an inoculum effect with cefepime proportional to the bacterial titre against the two strains, but more pronounced with the stably derepressed mutant strain, whereas with bacterial concentrations of up to 7 log10 cfu/mL, no inoculum effect was observed with amikacin . In-vitro killing indicated that antibiotic combinations were synergic only at intermediate concentrations . At peak concentrations, the combination was merely as effective as amikacin alone . At trough concentrations, a non-significant trend towards the superiority of the combination over each antibiotic alone was noted . Moreover, cefepime was either bacteriostatic or permitted regrowth of the organisms in the range of antibiotic concentrations tested . Although each antibiotic alone failed to decrease bacterial counts in the lungs, regardless of the susceptibility of the strain used, the combination of both antibiotics was synergic and induced a significant decrease in the lung bacterial count 24 h after starting therapy when compared with tissue bacterial numbers in untreated animals or animals treated with either antibiotic alone . No resistant clones emerged during treatment with any of the antibiotic regimens studied.

Urol Nefrol (Mosk), 1998 Mar-Apr, (2), 46 - 8
{The role of persisting microflora in the development of pathospermia}; Kuz'min MD et al.; The paper presents the results of the study of species composition and biological signs of microflora of the ejaculate obtained from infertile males . The strains of the microorganisms were characterized by high adhesive capacity and multiple resistance to antibiotics . High antilysozyme activity in staphylococci and enterobacteria isolated from the sterile patients was registered . The correlation between spermatozoa motility, lysozyme level in the ejaculate and bacterial ability to inactivate lysozyme is demonstrated the hypothesis about the role of persistent properties of bacteria in pathogenesis of male infertility is discussed.

J Clin Microbiol, 1998 May, 36(5), 1357 - 60
Nosocomial outbreak of Klebsiella pneumoniae producing SHV-5 extended-spectrum beta-lactamase, originating from a contaminated ultrasonography coupling gel; Gaillot O et al.; Klebsiella pneumoniae resistant to ceftazidime was isolated from six adult women and two neonates hospitalized between July and November 1993 in the Department of Obstetrics and Gynecology of Boucicaut Hospital (Paris, France) . The epidemiological investigation revealed a notably short delay (less than 48 h) between admission and contamination of the six adults and peripartum transmission to the neonates . The only environmental source of ceftazidime-resistant K . pneumoniae was the ultrasonography coupling gel used in the emergency room . Phenotypic (biotyping and antibiotyping) and genotypic (plasmid profile and pulsed-field gel electrophoresis) analysis of all the clinical isolates indicated the spread of a single strain . It produced SHV-5 and TEM-1 beta-lactamases, as demonstrated by isoelectric focusing and gene sequencing . The risk of cross-contamination in ultrasonography procedures is usually low and had not been associated so far with bacteria producing an extended-spectrum beta-lactamase (ESBL) . Furthermore, this is the first time an epidemic of an SHV-5 ESBL-producing member of the family Enterobacteriaceae has been reported from a French hospital.

Appl Environ Microbiol, 1998 May, 64(5), 1890 - 4
Ecophysiological and phylogenetic studies of Nevskia ramosa in pure culture; Sturmeyer H et al.; During the last 100 years, the neuston bacterium Nevskia ramosa has been described several times . This bacterium forms conspicuous rosette-like microcolonies at the air-water interface . In this study, pure cultures of Nevskia ramosa were obtained for the first time, from a bog lake (strain Soe1, DSMZ 11499T) and a freshwater ditch (strain OL1, DSMZ 11500) . The isolates showed special adaptations to life in the epineuston . They formed hydrophobic surface films with a dull appearance . N . ramosa is sensitive to UV radiation but revealed a very effective photorepair mechanism . Exposure to light at a wavelength of 350 nm after UV treatment raised the number of surviving cells by several orders of magnitude . The isolates grew with a broad range of organic substrates . Surface films were formed only in the absence of combined nitrogen; however, nitrogenase activity was not detected . It appears that during growth at the air-water interface the cells benefit from trapping ammonia from the air . The G + C content of the DNA was 67.8 and 69.0 mol% for strains Soe1 and OL1, respectively . The slight difference was confirmed by enterobacterial repetitive intergenic consensus PCR . The 16S rRNA sequences revealed 99.2% similarity . Thus, both isolates belong to the same species . The phylogenetic analysis indicated that Nevskia is a member of the gamma-subclass Proteobacteria that has no known close relatives.

Scand J Infect Dis, 1997, 29(6), 623 - 6
The influence of antimicrobial prophylaxis on the microbial and clinical findings in patients after autologous bone marrow transplantation; Haahr V et al.; The influence of a prophylactic regimen consisting of ciprofloxacin 250 mg bid, was examined by surveillance cultures from nose, throat, axilla, gingiva, exit site of central venous catheters, blood, rectum and urine of 60 patients undergoing autologous bone marrow transplantation during a 6-year period . None of the 60 patients developed any infectious with Gram-negative rods belonging to the Enterobacteriaceae, or deep fungal infections, during hospitalization . All patients were neutropenic . Febrile episodes were seen in all patients but 3 . From 13 patients, microorganisms in the blood, mostly nonhaemolytic streptococci (9/13), were cultured . Surveillance cultures did not predict later infections, but revealed the marked influence of the prophylactic antibiotics on the normal flora . Thus, mainly streptococci, coagulase-negative staphylococci and yeasts were cultured from the sites examined . It is concluded that the future objective of the microbiological surveillance should be restricted to monitoring the possible selection of drug-resistant microorganisms, and that routine cultures of blood and urine are unnecessary.

Scand J Infect Dis, 1997, 29(6), 601 - 6
Antibiotic therapy and outcome of monomicrobial gram-negative bacteraemia: a 3-year population-based study; Pedersen G et al.; Within the 3-y period 1992-94 a total of 815 episodes of monomicrobial bacteraemia caused by Enterobacteriaceae not including Salmonella were registered in the County of Northern Jutland . The 30-d case fatality rate was 24%, ranging from 21% for Enterobacter spp . (n = 43), 22% for E . coli (n = 577) to 32% for both Klebsiella spp . (n = 138) and a group of miscellaneous enterobacteria (n = 57) . In 16% of the bacteraemias, antibiotic treatment was not instituted before notification of positive blood cultures; in 9% empirical antibiotic treatment was inappropriate . Antibiotic regimens mainly included beta-lactams, ampicillin or mecillinam in combination with an aminoglycoside . The following factors were independently associated with case fatality: age > or = 75 y, high comorbidity index, admission to a medical ward or an intensive care unit, nosocomial acquisition, a source of infection outside the urinary tract or an undetermined focus, Klebsiella spp., inappropriate coverage or lack of antibiotic treatment before notification of positive blood culture . It is a matter of concern that in one-sixth of patients the physicians had not responded to the possibility of bacteraemia with institution of empirical antibiotic therapy.

Biochem Biophys Res Commun, 1998 Apr 17, 245(2), 572 - 82
The rfb genes in Azotobacter vinelandii are arranged in a rfbFGC gene cluster: a significant deviation to the arrangement of the rfb genes in Enterobacteriaceae; Hausman BS et al.; We report the identification of rfbF and rfbC located adjacent to the previously identified rfbG (Gavini et . al . Biochem . Biophys . Res . Commun . 1997, 240, 153-161) from the non-symbiotic, non-pathogenic soil bacterium Azotobacter vinelandii . The rfbF open reading frame encodes a putative polypeptide of 256 amino acids . This polypeptide shares a homology of 74% with the RfbF of Synechocystis sp . and a 70% homology with the AscA of Yersinia pseudotuberculosis which function as alpha-D-glucose-1-phosphate cytidylyltransferases in the biosynthesis of the O-antigen . The rfbC encodes a putative polypeptide of 186 amino acids . It shows strongest homology to the RfbC of Synechocystis sp . (64%) and Salmonella typhimurium (40%) . RfbC functions as a dTDP-4-Dehydrorhamnose 3,5-Epimerase . The genes identified here have a low G + C content (approximately 56%) as compared to the A . vinelandii chromosome (approximately 63%) which is characteristic of the rfb clusters identified in other bacteria and may be indicative of the acquisition of the rfb genes by interspecific gene transfer . Despite the high level of sequence conservation, the organization of the rfb genes in A . vinelandii deviates from the arrangement of the most thoroughly studied rfb gene clusters of Enterobacteriaceae.

Int J Biochem Cell Biol, 1997 Dec, 29(12), 1485 - 91
DNA-dependent RNA polymerase from Enterobacter cloacae is closely related to Escherichia coli; Gao N et al.; The RNA polymerase holoenzyme (RNAP) of Enterobacter cloacae was purified by gel filtration and heparin affinity chromatography and shown to consist of four subunits (beta', beta, alpha and sigma) of 156, 151, 45 and 82 kDa, as measured by SDS-PAGE . The 82 kDa protein was shown to be related to the Escherichia coli primary sigma factor by western blot analysis with polyclonal antisera raised against purified E . coli sigma 70 . Functional reconstitution of E . cloacae core enzyme with purified E . coli sigma 70 showed that E . cloacae and E . coli sigma factors are closely related . The RNAP of E . cloacae initiated transcription from the tac promoter with an efficiency similar to that of E . coli . Measuring promoter-specific transcription, the dependence of holoenzyme activity on salt, divalent cation and temperature was also similar to that of the E . coli RNAP . We also showed that the transcriptional inhibitor, rifampicin, inhibits the enzyme activity of the purified RNAP of E . cloacae and E . coli at similar concentrations . We conclude, based on these data, that the RNAP of E . cloacae and E . coli, both enterobacteria, are closely related.

Int J Syst Bacteriol, 1998 Jan, 48 Pt 1, 257 - 61
Phylogenetic characterization of the bacterium-like organism associated with marginal chlorosis of strawberry and proposition of a Candidatus taxon for the organism, 'Candidatus phlomobacter fragariae'; Zreik L et al.; Marginal chlorosis is a new disease of strawberry which was first seen in France in 1988 . A phloem-restricted bacterium-like organism was found associated with the disease . Even though the organism could not be cultured and resembles in this way most other phloem-restricted pathogens, characterization was achieved from the sequence of its PCR-generated 16S rDNA, and comparison with other organisms . From these studies, the strawberry agent was found to be a new bacterium within group 3 of the gamma subclass of Proteobacteria, a group of Gram-negative bacteria including, in particular, insect symbionts or parasites as well as enterobacteria . Its closest relative, Arsenophonus nasoniae, is the causal agent of the son-killer trait in wasps . The two bacteria share 92% 16S rDNA sequence identity . We propose a Candidatus taxon for the marginal-chlorosis-associated bacterium, 'Candidatus Phlomobacter fragariae'.

Am J Respir Crit Care Med, 1998 Apr, 157(4 Pt 1), 1165 - 72
Nosocomial pneumonia in patients with acute respiratory distress syndrome; Chastre J et al.; To describe the epidemiologic and microbial aspects of ventilator-associated pneumonia (VAP) in patients with acute respiratory distress syndrome (ARDS), we prospectively evaluated 243 consecutive patients who required mechanical ventilation (MV) for > or = 48 h, 56 of whom developed ARDS as defined by a Murray lung injury score > 2.5 . We did this with bronchoscopic techniques when VAP was clinically suspected, before any modification of existing antimicrobial therapy . For all patients, the diagnosis of pneumonia was established on the basis of culture results of protected-specimen brush (PSB) (> or = 10(3) cfu/ml) and bronchoalvelolar lavage fluid (BALF) (> or = 10(4) cfu/ml) specimens, and direct examination of cells recovered by bronchoalveolar lavage (BAL) (< or = 5% of infected cells) . Thirty-one (55%) of the 56 patients with ARDS developed VAP for a total of 41 episodes, as compared with only 53 (28%) of the 187 patients without ARDS for a total of 65 episodes (p = 0.0005) . Only 10% of first episodes of VAP in patients with ARDS occurred before Day 7 of MV, as compared with 40% of the episodes in patients without ARDS (p = 0.005) . All but two patients with ARDS who developed VAP had received antimicrobial treatment (mostly with broad-spectrum antibiotics) before the onset of infection, as compared with only 35 patients without ARDS (p = 0.004) . The organisms most frequently isolated from patients with ARDS and VAP were methicillin-resistant Staphylococcus aureus (23%), nonfermenting gram-negative bacilli (21%), and Enterobacteriaceae (21%) . These findings confirm that microbiologically provable VAP occurs far more often in patients with ARDS than in other ventilated patients . Because these patients are often treated with antibiotics early in the course of the syndrome, the onset of VAP is frequently delayed after the first week of MV, and is then caused mainly by methicillin-resistant S . aureus and other multiresistant microorganisms.

Ann Surg, 1998 Apr, 227(4), 547 - 52
Clinical impact of abnormal gut flora in infants receiving parenteral nutrition; Pierro A et al.; OBJECTIVE: Illness is associated with the carriage of abnormal flora (aerobic Gram-bacilli except E . coli) in the oropharynx and rectum . The aim of this study was to investigate whether carriage of abnormal flora is associated with increased risk of sepsis and septicemia in surgical newborn infants . METHODS: A 2-year prospective study was carried out on 94 consecutive newborn infants requiring parenteral nutrition (PN) for gastrointestinal abnormalities . Throat and rectal swabs were taken on day 1 of PN and twice weekly . Patients were divided into two groups: abnormal flora (AF; n = 41) and normal flora (NF; n = 53) . Sepsis was defined as clinical features of generalized inflammation requiring blood culture . Septicemia was the combination of sepsis and positive blood culture . RESULTS: Among the infants carrying abnormal flora Pseudomonas and Enterobacter spp . predominated . Duration of PN (AF median 30 days; NF median 9 days), incidence of sepsis (AF 29%; NF 6%), and septicemia (AF 22%; NF 2%) were significantly greater in the group of infants with abnormal flora . Surveillance cultures allow the detection of a subset of infants on PN at high risk of sepsis and septicemia . The degree of gut dysfunction related to the severity of underlying disease determines the duration of PN and the development of abnormal flora . The association between abnormal carriage and increased risk of sepsis and septicemia may be because of the intestinal endotoxin pool known to cause liver impairment and consequent suppression of systemic immunity.

Transfusion, 1998 Mar, 38(3), 229 - 35
The relationship between the duration of platelet storage and the development of transfusion reactions; Sarkodee-Adoo CB et al.; BACKGROUND: The incidence of platelet transfusion reactions may depend partly on the length of storage . The influence of reactions on the effectiveness of platelet transfusions is not known . STUDY DESIGN AND METHODS: Platelet transfusion reactions, identified by prospective monitoring, were analyzed for the effects of component type, recipient lymphocytotoxic antibodies, bacterial contamination, and duration of storage . Posttransfusion corrected count increments (CCIs) were used to evaluate the effectiveness of transfusions associated with reactions by comparing them to those of randomly selected transfusions without reactions . RESULTS: Reactions accompanied 4 percent of the 4926 transfusions given and included 119 febrile nonhemolytic transfusion reactions, 62 allergic reactions, and 13 reactions with features of both . Platelet concentrates contained a mean of 0.5 x 10(8) white cells per unit . Lymphocytotoxic antibodies were detectable in 20 of 84 recipients tested proximate to a reaction . Bacterial cultures from 4 of 81 units were positive; 1 unit was associated with fatal Enterobacter sp . sepsis . The incidence of febrile nonhemolytic transfusion reactions but not allergic reactions was related to platelet storage duration . The CCI was not significantly different for transfusions associated with reactions (10.97 {median, range 0-72.5; n = 165}) or not so associated (13.1 {median, range 0-39.5; n = 174}) (p = 0.08) . CONCLUSION: The incidence of febrile nonhemolytic transfusion reactions but not allergic reactions appears to be related to the duration of platelet storage . Transfusion reactions may not have an adverse impact on the effectiveness of platelet transfusions.

Naturwissenschaften, 1998 Mar, 85(3), 99 - 108
Molecular mechanisms of bacterial pathogenicity; Fuchs TM; Cautious optimism has arisen over recent decades with respect to the long struggle against bacteria, viruses, and parasites . This has been offset, however, by a fatal complacency stemming from previous successes such as the development of antimicrobial drugs, the eradication of smallpox, and global immunization programs . Infectious diseases nevertheless remain the world's leading cause of death, killing at least 17 million persons annually {61} . Diarrheal diseases caused by Vibrio cholerae or Shigella dysenteriae kill about 3 million persons every year, most of them young children: Another 4 million die of tuberculosis or tetanus . Outbreaks of diphtheria in Eastern Europe threatens the population with a disease that had previously seemed to be overcome . Efforts to control infectious diseases more comprehensively are undermined not only by socioeconomic conditions but also by the nature of the pathogenic organisms itself; some isolates of Staphylococcus aureus and Enterobacter have become so resistant to drugs by horizontal gene transfer that they are almost untreatable . In addition, the mechanism of genetic variability helps pathogens to evade the human immune system, thus compromising the development of powerful vaccines . Therefore detailed knowledge of the molecular mechanisms of microbial pathogenicity is absolutely necessary to develop new strategies against infectious diseases and thus to lower their impact on human health and social development.

Int J Food Microbiol, 1998 Jan 6, 39(1-2), 101 - 10
Mathematical modelling of microbial growth in packaged refrigerated beef stored at different temperatures; Giannuzzi L et al.; Gompertz and logistic models were fitted to experimental counts of microorganisms growing in beef stored at 0, 4, 7, 9 and 10 degrees C . Samples were packaged in polyethylene (high gaseous permeability) and in EVA/SARAN/EVA (low gaseous permeability) films, being EVA ethyl vinyl acetate and SARAN polyvinyl and polyvinylidene chloride copolymer . Lag phase duration (LPD) and specific growth rate (mu) were obtained as derived parameters for lactic acid bacteria, Enterobacteriaceae, Pseudomonas sp . and psychrotrophic microorganisms . The reciprocal of LPD was fitted to an Arrhenius type equation; LPD of lactic acid bacteria showed a marked dependence on temperature, with activation energy values (ELPD) of 222.2 and 216.9 kJ/mol for polyethylene and ESE respectively . The effect of initial microbial population at different storage temperatures on adaptation period was analyzed . As the initial microbial population increased, adaptation period decreased for all studied microorganisms and for both packaging films . The effect of temperature on specific growth rate was better interpreted by the Arrhenius model than by the linear or the square root equations . Psychrotrophic microorganisms in beef showed the highest activation energy values for specific growth rate (E mu) in both packaging films, being E mu 85.50 and 103.10 KJ/mol for polyethylene and ESE film respectively . In both films, Enterobacteriaceae showed the lowest E mu values, being 15.33 and 59.89 kJ/mol in ESE and polyethylene respectively . The final number of microorganisms (maximum population density) did not show significant changes with storage temperature.

Acta Clin Belg, 1998 Feb, 53(1), 28 - 38
A multicentre survey of antimicrobial resistance in gram-negative isolates from Belgian intensive care units in 1994-1995 . Belgian Multicenter ICU Study Group; Glupczynski Y et al.; The aim of this prospective study was to evaluate the distribution and antibiotic susceptibility of aerobic Gram-negative bacilli isolated from patients in intensive care units in 18 Belgian hospitals during 1994 and 1995 . A standardised method (i.e . the E-test) was used in each center to determine the minimum inhibitory concentrations of 12 major antibiotics against 1435 consecutive, non duplicate, Gram-negative isolates (close to 100 strains per hospital) during a period of 6 months . The isolates were mainly isolated from the lower respiratory tract (57.4%), urinary tract (17.7%), pus (7.9%) or blood specimens (7.8%) and were mainly P.aeruginosa (20.3%), E.coli (19.9%) and Enterobacter spp . (12.6%) . Overall inducible Enterobacteriaceae (IE) accounted for 29.8% of all isolates, and E.aerogenes was the most frequently isolated species in this group (27.6%) . The overall susceptibility rate (all species confounded) was about 70% to piperacillin, ticarcillin-clavulanic acid and ceftriaxone, 78% to piperacillin-tazobactam; 87% both to ceftazidime and to ciprofloxacin; and 90% to imipenem . Widespread resistance was observed in several IE species to third generation cephalosporins, broad-spectrum penicillins and to ciprofloxacin . By contrast, imipenem and the aminoglycosides still retained excellent activity against most multiresistant species . Although there were wide differences between hospitals in the frequencies of resistance to most antibiotics, these were not related to the types (general vs . university) of hospitals or to the number of beds . Some variations were however observed in the distribution of bacterial species: the prevalence of inducible Enterobacteriaceae was significantly higher in university than in general hospitals and in hospitals located in Brussels and in Wallonia than in the Flanders . Overall few trends in resistance rates were observed in comparison to a similar survey performed in 1991.

Eur J Surg, 1998 Mar, 164(3), 223 - 8
Microbial translocation and impairment of mucosal immunity induced by an elemental diet in rats is prevented by selective decontamination of the digestive tract; Spath G et al.; OBJECTIVE: To assess the effect of selective decontamination of the digestive tract (SDD) on intestinal secretory immunoglobulin A (sIgA) concentrations in a model of intestinal bacterial overgrowth and bacterial translocation induced by an elemental diet in rats . DESIGN: Laboratory study . SETTING: University hospital, Germany . MATERIAL: 45 specific pathogen free female Crl:CD(R) BR rats . INTERVENTIONS: For 7 days, 3 groups of rats were fed orally with standard chow (n = 15), total parenteral nutrition solution (ORAL-TPN, n = 15), or ORAL-TPN plus tobramycin (20 mg/L) and polymyxin E (25 mg/L) (ORAL-TPN + SDD) . MAIN OUTCOME MEASURES: Bacterial translocation to mesenteric lymph nodes (MLN), numbers of gram negative enterobacteria and total aerobic bacteria in the caecum, and intestinal concentrations of sIgA . RESULTS: The incidence of bacterial translocation was significantly increased in the group given ORAL-TPN (8/15, 53%) compared with the group given chow (1/15, 7%, p < 0.01) . Supplementation of ORAL-TPN with SDD reduced translocation to 0/15 . The ORAL-TPN group had a pronounced overgrowth of aerobic bacteria in the caecum, mainly by gram negative enterobacteria, which was prevented by the SDD . The concentrations of intestinal sIgA were significantly reduced in the ORAL-TPN group . SDD resulted in both the soluble and insoluble sIgA fractions in the gut being within the reference ranges . CONCLUSION: SDD prevents gram negative caecal overgrowth and translocation to MLN in rodents fed on ORAL-TPN . The significantly reduced mucosal immunity caused by ORAL-TPN alone is restored by SDD, although one might have expected a further reduction in sIgA concentrations with lower microbial populations than in the ORAL-TPN group . Not only does SDD not seem to affect the mucosa associated immune system adversely, but also depressed mucosal immunity was restored.

J Vet Intern Med, 1998 Mar-Apr, 12(2), 76 - 8
Results of quantitative cultures of urine by free catch and catheterization from healthy adult horses; MacLeay JM et al.; Quantitative urine cultures were performed on 11 male and 11 female healthy adult horses . Urine was collected by free catch and catheterization using standard methods . Results showed that all samples collected by free catch contained less than 20,000 colony-forming units (CFU)/mL . All samples collected by catheterization contained 500 CFU/mL or less . A significant difference was found between collection methods (P < .005), with catheterization having less contamination . In samples collected by free catch, females had significantly greater contamination than did males (P < .03) . Predominant bacterial species isolated included Streptococcus spp., Escherichia coli, Enterobacter sp., Bacillus sp., Staphylococcus spp., Diptheroids sp., Proteus spp., and Enterococcus sp . Many samples contained multiple bacterial species . Bacterial isolates were representative of the normal bacterial flora of the equine urogenital tract . This paper establishes reference values for quantitative urine culture results in healthy adult horses to aid in the diagnosis of urinary tract infections.

Chemotherapy, 1998 Mar-Apr, 44(2), 77 - 84
In vitro activity of enoxacin versus ciprofloxacin, fleroxacin, lomefloxacin, ofloxacin, pefloxacin, and rufloxacin against uropathogens; Naber KG et al.; Minimum inhibitory concentrations (MIC) of enoxacin, ciprofloxacin, fleroxacin, lomefloxacin, ofloxacin, pefloxacin and rufloxacin were determined against 400 uropathogens cultured from the urine of patients with complicated and/or hospital-acquired urinary tract infections (UTI) using an agar dilution method . The bacterial spectrum consisted of Entero-bacteriaceae (34.5%), enterococci (31.5%), staphylococci (21.2%) and non-fermenting bacteria (12.8%) . Enoxacin inhibited all but one strain (Enterobacter cloacae) of Enterobacteriaceae up to an MIC of 1 mg/l (MIC90 0.25 mg/l) . Regarding the total bacterial spectrum, enoxacin inhibited 54.5, 59.5, 76.0 and 83.8% up to an MIC of 1, 2, 4 and 8 mg/l, respectively . If the same breakpoint of resistance for ofloxacin according to DIN 58,940 (NCCLS), i.e . MIC > or = 4 mg/l (> or = 8 mg/l), is also taken for the other fluoroquinolones, and the 126 strains of enterococci are excluded, for which alternative agents, e.g . aminopenicillins, should be considered instead, the following resistance rates were found: ciprofloxacin and enoxacin 15.3% (15.0%), ofloxacin 17.2% (15.3%), pefloxacin 18.2% (15.3%), fleroxacin 19.3% (15.3%), lomefloxacin 19.7% (17.9%) and rufloxacin 31.8% (27.4%) . According to their in vitro activity, all fluoroquinolones tested besides rufloxacin show similar rates of resistance against uropathogens and can therefore be considered good alternative agents for the treatment of complicated UTI.

Antimicrob Agents Chemother, 1998 Apr, 42(4), 879 - 84
Discriminatory detection of inhibitor-resistant beta-lactamases in Escherichia coli by single-strand conformation polymorphism-PCR; Speldooren V et al.; Plasmid-mediated mechanisms, comprising TEM hyperproduction, TEM derivative production, and OXA production, lead to amoxicillin-clavulanic acid resistance in enterobacteria . The ability of the single-strand conformation polymorphism (SSCP)-PCR method to differentiate the genes encoding inhibitor-resistant beta-lactamases was evaluated with three bla(TEM) primer pairs . The bla(TEM) genes, which were known to be different on the basis of their nucleotide sequences (bla{TEM-1A}, bla{TEM-1B}, bla{TEM-2}, bla{TEM-30}, bla{TEM-32}, and bla{TEM-35}), were identified as different by their electrophoretic mobilities . The bla(TEM-33), bla(TEM-34), bla(TEM-36), bla(TEM-37), bla(TEM-38), and bla(TEM-39) genes, whose sequence differences have been established by oligotyping, displayed different SSCP profiles for different fragments, suggesting genetic differences in addition to those defined by oligotyping . Confirmed by sequencing, these additional genetic events concerned silent mutations at certain positions and, notably, a G-->T transversion at position 1 of the -10 consensus sequence in bla(TEM-34), bla(TEM-36), bla(TEM-37), and bla(TEM-39) . Applied to eight clinical isolates of Escherichia coli resistant to amoxicillin-clavulanic acid, the SSCP method detected TEM-1 in three strains and TEM-30, TEM-32, and TEM-35 in three other strains, respectively . A novel TEM derivative (TEM-58) was detected in another strain, and the deduced amino acid sequence showed two substitutions: Arg244Ser, which is known to confer amoxicillin-clavulanic acid resistance in TEM-30, and Val261Ile, which has not been described previously . The eighth strain produced an OXA beta-lactamase . Given the discriminatory power and the applicability of SSCP-PCR, this method can be proposed as a means of following the evolution of the frequencies of the different inhibitor-resistant beta-lactamases.

Vet Res, 1998 Jan-Feb, 29(1), 3 - 19
{Epidemiologic markers of Salmonella}; Millemann Y; Salmonellae are enterobacteria responsible for outbreaks of human and animal clinical diseases, with important hygienic and economic consequences . Accurate epidemiological studies require the use of efficient markers, which make it possible to trace the establishment and diffusion of different bacterial strains and also to evaluate the similarities between different isolates . Numerous phenotypic and genotypic markers applicable to Salmonella are available for these epidemiological studies . Nevertheless, the relative interest of those markers depends on the serotypes, and a different hierarchy can be achieved for the Typhimurium and Enteritidis serotypes.

Zentralbl Veterinarmed B, 1998 Mar, 45(2), 65 - 71
Infectious bovine mastitis caused by environmental organisms; Costa EO et al.; The purpose of this study was to determine the prevalence of environmental mastitis in dairy herds and identify the main environmental pathogens, and to evaluate the influence of season, housing and management . A total of 20,310 quarters of 5216 animals from 52 dairy herds in 32 counties was examined . Milk samples were aseptically collected for laboratory examination from mammary glands testing positive to any of the field tests . From these, 736 environmental infections were identified . The most frequently isolated environmental pathogens were algae of the genus Prototheca sp . (41.2%), Streptococcus uberis (21.1%), fungi (19.5%), enterobacteriacea (8.3%) and Nocardia sp . (6.6%) . The occurrence of mastitis was not influenced by the herd size, use of dry cow therapy, or post milking teat dipping . A tendency for increased occurrence of environmental mastitis during the months of September to February (hot and wet weather) was observed, suggesting a seasonal influence.

J Bacteriol, 1998 Apr, 180(8), 2144 - 51
Variation of the ribosomal operon 16S-23S gene spacer region in representatives of Salmonella enterica subspecies; Perez Luz S et al.; The 16S-23S spacer regions of two ribosomal operons (rrnA and rrnE) have been sequenced in seven representatives of the Salmonella enterica subspecies . Isolated nucleotide substitutions were found at the same sites as in Escherichia coli but the number of polymorphic sites was much larger, as could be expected for a more heterogeneous species . Still, as in E . coli, most of the variation found was due to insertions and/or deletions affecting blocks of nucleotides generally located at equivalent regions of the putative secondary structure for both species . Isolated polymorphic sites generated phylogenetic trees generally consistent with the subspecies structure and the accepted relationships among the subspecies . However, the sequences of rrnE put subspecies I closer to E . coli K-12 than to the other S . enterica subspecies . The distribution of polymorphisms affecting blocks of nucleotides was much more random, and the presence of equivalent sequences in distantly related subspecies, and even in E . coli, could reflect relatively frequent horizontal transfer . The smallest 16S-23S spacers in other genera of the family Enterobacteriaceae were also sequenced . As expected, the level of variation was much larger . Still, the phylogenetic tree inferred is consistent with those of 16S rRNA or housekeeping genes.

Int J Food Microbiol, 1998 Feb 17, 39(3), 227 - 30
Amino acid decarboxylase capability of microorganisms isolated in Spanish fermented meat products; Santos MH; Enterobacteria, lactic acid bacteria (LAB) and Gram-positive cocci were isolated from Spanish meat products . The most frequent species in the meat products studied were identified as Lactobacillus sake, Lactobacillus plantarum and Lactobacillus curvatus from De Man-Rogosa-Sharpe agar; Staphylococcus xylosus, Staphylococcus saprophyticus and Micrococcus varians from mannitol salt phenol-red agar; and Hafnia alvei, Escherichia coli, Pseudomonas fluorescens, Enterobacter amnigenes and Enterobacter aerogenes from violet red bile dextrose agar . The amino acid decarboxylase activity of the microorganisms isolated was assayed . Enterobacteria had higher amino acid decarboxylase activity than the other groups . LAB did not show any significant amino acid decarboxylase capability in this study.

Int J Food Microbiol, 1998 Feb 17, 39(3), 155 - 66
Evaluation of the role of Carnobacterium piscicola in spoilage of vacuum- and modified-atmosphere-packed cold-smoked salmon stored at 5 degrees C; Paludan-Muller C et al.; The microflora on spoiled cold-smoked salmon often consists of a mixture of lactic acid bacteria (LAB) and Gram-negative bacteria . To elucidate the role of the different groups, a storage trial was carried out in which nisin and CO2 were used for the selective inhibition of the two bacterial groups . The shelf-life of vacuum-packed cold-smoked salmon, recorded by sensory evaluation, was four weeks at 5 degrees C and the microflora was composed of LAB (10(6)-10(7) cfu/g) with an associate Gram-negative flora in varying levels (10(5)-10(7) cfu/g) . The addition of nisin and/or a CO2-atmosphere increased the shelf-life to five or six weeks and limited the level of LAB to about 10(4)-10(6), 10(3)-10(6) and 10(2)-10(4) cfu/g, respectively . CO2-atmosphere +/- nisin inhibited the growth of Gram-negative bacteria, whereas nisin had no effect on these in vacuum packages . The Gram-negative flora on vacuum-packed salmon was dominated by a Vibrio sp., resembling V . marinus, Enterobacteriaceae (Enterobacter agglomerans, Serratia liquefaciens and Rahnella aquatilis) and occasionally Aeromonas hydrophila . Irrespective of the addition of nisin and/or CO2-atmosphere, the LAB microflora was dominated by Carnobacterium piscicola, which was found to account for 87% of the 255 LAB isolates characterized . Whole-cell-protein patterns analysed by SDS-PAGE confirmed the Carnobacterium species identification . The spoilage potential of C . piscicola isolates was further studied by inoculation of approx . 10(6) cfu/g in cold-smoked salmon stored at 5 degrees C . The salmon did not spoil within 4 weeks of storage in vacuum- or CO2-atmosphere, and it is concluded that despite high levels (> 10(7) cfu/g) of C . piscicola, sensory rejection was caused by autolytic changes . This was supported by the development of soft texture and sour, rancid and bitter off-flavours at the point of spoilage, irrespective of the length of shelf-life and low or high total counts of LAB and Gram-negative bacteria.

Clin Oral Investig, 1997 Feb, 1(1), 47 - 52
Miconazole lacquer in the treatment of denture stomatitis: clinical and microbiological findings in Chinese patients; Dias AP et al.; OBJECTIVE: To investigate the efficacy of a miconazole lacquer in producing mycological and clinical cure of Candida-associated denture stomatitis in a Chinese cohort and to study the microbiology of the conditions . DESIGN: A cross-sectional study of the clinical and microbiological features of the condition and its response to treatment with the lacquer . SUBJECTS AND METHOD: Twenty-one Chinese adults with palatal erythema; 15 denture wearers matched for age and sex as controls for microbiology . Clinical examination, impression for culture, photograph of palate to monitor response to treatment, and lacquer application on upper denture base on days 0, 7 and 14 . Impression and photograph repeated on day 21; impression cultures quantified by image analysis . Palatal impression in controls; dummy impression as control for impression culture procedures . MAIN OUTCOME MEASURES: Severity of lesion, incidence and type of microorganism at presentation and during treatment; qualitative and quantitative assessment of yeast growth; the latter by statistical analysis of pixel units of yeast colonies; correlation of clinical and mycological cure . RESULTS: Out of the 21 lesions (16 Newton's stage I and 5 stage II), 57% had yeasts at presentation, 10% coliforms and 33% no significant growth . Clinical cure in 3 weeks in 71%, mycological cure in 75% in 7 days; clinical and mycological cure coincided only in 43% . Polymicrobial growth of yeasts and coliforms throughout the course in some . CONCLUSIONS: Miconazole lacquer was a viable treatment option for Candida-associated denture stomatitis in this adult, Chinese cohort; microbiology comprised yeasts, mainly C . albicans and coliforms, especially Klebsiella and Enterobacter species; the pathogenic role of the latter is questionable.

Int J Antimicrob Agents, 1997 Jan, 9(3), 165 - 7
ERIC-PCR typing profiles of Enterobacter cloacae are stable after development of advanced cephalosporin resistance; Zaher A et al.; Enterobacterial repetitive intergenic consensus (ERIC) sequence polymerase chain reaction genotype profiles of Enterobacter cloacae were prepared for paired isolates which were obtained before and after the high level expression of the chromosomal cephalosporinase . These profiles were homologous within strain pairs which suggests that the acquired resistance does not lead to major chromosomal alterations . ERIC genotypes are therefore reliable markers in epidemiological investigations where antibiogram modifications may arise as a consequence of antibiotic exposure and beta-lactamase over-production..

Farmaco, 1997 Nov, 52(11), 685 - 9
Synthesis and microbiological activity of some novel N-(2-hydroxyl-5-substitutedphenyl)benzacetamides, phenoxyacetamides and thiophenoxyacetamides as the possible metabolites of antimicrobial active benzoxazoles; Yalcin I et al.; Synthesis of some novel N-(2-hydroxyl-5-substitutedphenyl)benzacetamides, phenoxyacetamides and thiophenoxyacetamides (5a-k) were described in order to determine their in vitro antimicrobial activity against 3 Gram-positive, 3 Gram-negative bacteria and the fungus Candida albicans comparing with several control drugs . The derivative 5e was found active at a MIC value of 25 micrograms/ml against the whole tested Gram-positive bacteria strains and the Gram-negative microorganism Klebsiella pneumoniae . Moreover, the synthesized compounds 5a-k exhibited significant antibacterial activity against the enterobacter Pseudomonas aureginosae when compared to the control drugs . For the antifungal avtivity against C . albicans, the compound 5k was found more active than the other synthesized derivatives . On the other hand, the antimicrobial activity of some of these acetamide derivatives (5c, 5d, 5e, 5j and 5k) which are the possible metabolites of benzoxazoles, were also compared with their cyclic analogues 6-10 . However, most of the MIC values of the benzoxazole derivatives provided better activity than the compared acetamides, while some others of the acetamide derivatives possessed either one fold improved (5d, 5e and 5j) or the same potency (5c, 5d, 5e, 5j and 5k) against the tested microorganisms.

Vet Microbiol, 1998 Jan 16, 59(2-3), 157 - 74
Characterisation of epitopes of type 1 fimbriae of Salmonella using monoclonal antibodies specific for SEF21 fimbriae of Salmonella enteritidis; Sojka MG et al.; Monoclonal antibodies (mAbs) were used to identify and characterise epitopes of type 1 (SEF21) fimbriae of Salmonella enteritidis . The distribution of the epitopes among salmonellas and other enterobacteria was investigated, as well as the influence of growth media and temperatures on their expression . At least four different epitope clusters were identified on SEF21 fimbriae of S . enteritidis . Two of these clusters were associated with fimbrial haemagglutinins that were either common to all salmonellae tested, or restricted only to S . enteritidis and S . dublin . The four epitope clusters were identified on type 1 fimbriae of most Salmonella serotypes, as well as non-haemagglutinating type 2 fimbriae of S . pullorum and S . gallinarum, and on many other enterobacterial species . The expression of the epitopes was affected by growth conditions.

J AOAC Int, 1998 Mar-Apr, 81(2), 438 - 40
Comparison of the VITEK Gram-Negative Identification Card and an enhanced version for identification of Salmonella, Escherichia coli, and other Enterobacteriaceae: method modification; Gravens CK; The VITEK Gram-Negative Identification Card (GNI) was compared to an enhanced version of the test kit, the GNI + Card . The GNI Card is an official AOAC method (991.13) for identification of Salmonella, Escherichia coli, and other Enterobacteriaceae in foods . In this comparison 5 replicates of 124 gram-negative stock culture strains were evaluated to determine equivalency . Isolates were obtained primarily from food sources, with 108 of the isolates representing 15 genera within the family Enterobacteriaceae . Overall agreement between the GNI Card and the GNI + Card was 98.2% . Of the 23 strains of Salmonella tested, the longest identification time for the GNI Card was 10 h, with 43.5% of the strains identifying in 4 h or less . The longest identification time of the same Salmonella strains tested with the GNI + Card was 8 h, with 95.7% of the strains identifying within 4 h . The GNI + Card provided increased speed of identification while retaining the accuracy of the GNI Card . The GNI method for identifying Salmonella, Escherichia coli, and other Enterobacteriaceae was approved as a method modification by AOAC INTERNATIONAL.

J Nat Prod, 1998 Feb 27, 61(2), 207 - 11
Isolation and Identification of Two l-Azetidine-2-carboxylic Acid-Degrading Soil Microorganisms, Enterobacter agglomerans and Enterobacter amnigenus
Yeung KF, Lee KM, Woodard RW.
Soil samples collected at several times during the growing season and at different locations within Convallaria majalis beds in Ann Arbor, MI, were screened for their ability to grow with the cyclic amino acid, l-azetidine-2-carboxylic acid (l-A-2-C), as their sole nitrogen source (i.e., metabolize l-A-2-C) . Two different soil microorganisms were isolated, characterized, and identified using fundamental selection methods, the standard battery of biochemical characterization tests, and scanning electron microscopy . The assignment of the identity of these organisms as Enterobacter agglomerans and Enterobacter amnigenus was further verified by comparison with authentic microbial samples obtained from ATCC that were able to utilize l-A-2-C as their sole nitrogen source.

Appl Environ Microbiol, 1998 Apr, 64(4), 1319 - 22
Biodegradation of metal-EDTA complexes by an enriched microbial population; Thomas RA et al.; A mixed culture utilizing EDTA as the sole carbon source was isolated from a mixed inoculum of water from the River Mersey (United Kingdom) and sludge from an industrial effluent treatment plant . Fourteen component organisms were isolated from the culture, including representatives of the genera Methylobacterium, Variovorax, Enterobacter, Aureobacterium, and Bacillus . The mixed culture biodegraded metal-EDTA complexes slowly; the biodegradability was in the order Fe > Cu > Co > Ni > Cd . By incorporation of inorganic phosphate into the medium as a precipitant ligand, heavy metals were removed in parallel to EDTA degradation . The mixed culture also utilized a number of possible EDTA degradation intermediates as carbon sources.

Appl Environ Microbiol, 1998 Apr, 64(4), 1210 - 9
Self-transmissible mercury resistance plasmids with gene-mobilizing capacity in soil bacterial populations: influence of wheat roots and mercury addition; Smit E et al.; A set of mercury resistance plasmids was obtained from wheat rhizosphere soil amended or not amended with mercuric chloride via exogenous plasmid isolation by using Pseudomonas fluorescens R2f, Pseudomonas putida UWC1, and Enterobacter cloacae BE1 as recipient strains . The isolation frequencies were highest from soil amended with high levels of mercury, and the isolation frequencies from unamended soil were low . With P . putida UWC1 as the recipient, the isolation frequency was significantly enhanced in wheat rhizosphere compared to bulk soil . Twenty transconjugants were analyzed per recipient strain . All of the transconjugants contained plasmids which were between 40 and 50 kb long . Eight selected plasmids were distributed among five groups, as shown by restriction digestion coupled with a similarity matrix analysis . However, all of the plasmids formed a tight group, as judged by hybridization with two whole-plasmid probes and comparisons with other plasmids in dot blot hybridization analyses . The results of replicon typing and broad-host-range incompatibility (Inc) group-specific PCR suggested tht the plasmid isolates were not related to any previously described Inc group . Although resistance to copper, resistance to streptomycin, and/or resistance to chloramphenicol was found in several plasmids, catabolic sequences were generally not identified . One plasmid, pEC10, transferred into a variety of bacteria belonging to the beta and gamma subdivisions of the class Proteobacteria and mobilized as well as retromobilized the IncQ plasmid pSUP104 . A PCR method for detection of pEC10-like replicons was used, in conjunction with other methods, to monitor pEC10-homologous sequences in mercury-polluted and unpolluted soils . The presence of mercury enhanced the prevalence of pEC10-like replicons in soil and rhizosphere bacterial populations.

Protein Expr Purif . 1998 Apr;12(3):IV.
Papers to appear in forthcoming issues
Genotypic and phenotypic characterization of two Swedish isolates and two prototypic strains of Coxiella burnetii.
Department of Microbiology, Defence Research Establishment, Umea, Sweden . sjostedt@ume.foa.se

Two Swedish isolates of Coxiella burnetii and the two prototype strains of the species, Nine Mile and Priscilla, were characterized with regard to their multiplication and cytopathic effect on BGM cells and by PCR-based amplification of repetitive element DNA and the C . burnetii-specific plasmids QpH1 and QpRS . Moreover, 1330 bp of each 16S rRNA gene were sequence-determined . All four strains multiplied at virtually the same rate and displayed the same type of vacuoles in the BGM cells . Genetic homogeneity was observed inasmuch as the 16S rDNA sequences were identical and the strains showed identical PCR amplification patterns using primers specific to enterobacterial repetitive intragenic consensus DNA sequences . The two Swedish strains and the Priscilla strain also showed identical patterns after PCR amplification of repetitive extragenic palindromic DNA sequences, whereas the Nine Mile strain demonstrated a similar, but not identical pattern . Thus, the investigated strains demonstrated very similar phenotypic and genotypic characteristics . This finding is discussed in view of the very rare occurrence of domestic Q fever in Sweden.

Clin Transplant, 1998 Feb, 12(1), 19 - 23
Urinary tract infections following renal transplantation; Takai K et al.; The incidence of urinary tract infections (UTIs) in 363 adult renal transplant recipients transplanted during the period 1990-96 has been analysed . UTI occurred in 96 patients (26%), most frequently during the first year after transplantation . Female recipients had significantly more UTI than male recipients (49% vs . 14%, p < 0.0001) . There was no difference in the incidence of UTI between recipients receiving pig-tail catheters as ureteral stents or not, the figures being 21% vs . 28%, respectively . Age had no influence on the incidence of UTI . In 341 patients treated with cyclosporine the incidence of UTI was 28%, while in 15 patients treated with FK-506 only 1 patient (7%) had a UTI (ns) . The majority of organisms cultured were gram-negative (76%), with approximately 1/3 being Escherichia coli and 1/5 being Enterococcus and Klebsiella/Enterobacter . The bacterial spectrum was not influenced by the recipient's age . UTI had no effect on the number of rejections, or on graft and patient survival in living donor transplant recipients . No significant difference was found in graft and patient survival rates at 3 yr between patients who had UTI or no UTI.

J Pediatr Surg, 1998 Mar, 33(3), 417 - 21
Pyogenic liver abscess in children--South Indian experiences; Kumar A et al.; PURPOSE: Eighteen cases of pyogenic liver abscess (PLA) admitted at JIPMER hospital, South India, over a 6-year period were analyzed to document the clinical profile and to evaluate the management of PLA among children . METHODS: Records of all these patients were reviewed for presenting signs and symptoms, any associated condition, investigative results, management, and follow-up findings . RESULTS: The overall incidence of PLA was 78.9 per 100,000 pediatric (under 12 years) admissions . One patient had aplastic anemia and was on long-term steroid therapy, whereas another had measles in recent past . Moderate to severe malnutrition was present in five (27.8%) and ascariasis in seven (38.9%) children . Common presentations were fever (100%), abdominal pain (76.9%), and tender hepatomegaly (83.3%) . Ultrasonography results were positive in all cases . Fourteen patients (77.8%) had solitary liver abscess, and four had multiple abscesses . Organism was isolated in 11 cases (63.6%), and Staphylococcus aureus was the commonest isolate (66.7%) . All patients received antibiotics . Twelve cases were managed conservatively with antibiotics alone, of these only two (16.7%) required drainage later on . Percutaneous aspiration was also undertaken in four additional (22.2%) cases and open drainage in two (11.1%), at presentation . The overall mortality rate was 11.1% . Time taken for complete resolution ranged from 10 days to 40 days . CONCLUSIONS: Any child presenting with fever, abdominal pain, and tender hepatomegaly should be subjected to ultrasound scan for early detection of PLA . S aureus is the commonest causative agent . Enterobacteriaceae contribute significantly during infancy . A combination of cloxacillin and gentamicin or a third generation cephalosporine and gentamicin, especially in infants, is a satisfactory initial coverage . Therapeutic drainage is not a must in all cases of PLA . When required, percutaneous needle aspiration is safe and effective . Resolution and significant reduction in mortality has been made possible by early detection and optimum antibiotics therapy.

J Bacteriol, 1998 Apr, 180(7), 1959 - 61
Occurrence of homologs of the Escherichia coli lytB gene in gram-negative bacterial species; Potter S et al.; The Escherichia coli LytB protein regulates the activity of guanosine 3',5'-bispyrophosphate synthetase I (RelA) . A Southern blot analysis of chromosomal DNA with the E . coli lytB gene as a probe revealed the presence of lytB homologs in all of the gram-negative bacterial species examined but not in gram-positive species . The lytB homologs from Enterobacter aerogenes and Pseudomonas fluorescens complemented the E . coli lytB44 mutant allele.

Pediatr Infect Dis J, 1998 Mar, 17(3), 224 - 30
The clinical spectrum of respiratory syncytial virus disease in The Gambia; Weber MW et al.; BACKGROUND: Respiratory syncytial virus (RSV) is a well-recognized cause of lower respiratory tract infections in early childhood in industrialized countries, but less is known about RSV infection in developing countries . METHODS: Four outbreaks of RSV infection that occurred between 1993 and 1996 in The Gambia, West Africa, were studied . RSV was sought by immunofluorescent staining of nasopharyngeal aspirate samples among young children who presented with respiratory infections at three hospitals in the Western Region of the country . RESULTS: Five hundred seventy-four children with RSV infection were identified . The median ages of children seen in 1993 through 1996 were 3, 7, 8 and 5 months, respectively . Sixty-two percent of children <6 months old were boys . Thirteen children (2.4%) had conditions considered to increase the risk of severe RSV infection . On physical examination crepitations were heard in 80% of the children admitted to hospital, whereas wheezes were heard in only 39% . Eighty (16%) children received oxygen because of hypoxemia . Nine of 255 blood cultures (3.5%) were positive: 4 Streptococcus pneumoniae; 2 Haemophilus influenzae type b; 2 Staphylococcus aureus; and 1 Enterobacter agglomerans . Thirteen children died (2.4%) . During the 4 study years 90, 25, 75 and 95% of isolates typed were RSV Subgroup A, respectively . CONCLUSIONS: RSV is a significant cause of lower respiratory tract infection in young children in The Gambia, causing epidemics of bronchiolitis . It poses a significant burden on the health system, especially through the demand for supplementary oxygen . The clinical spectrum of RSV disease in The Gambia is similar to that seen in developed countries; concomitant bacterial infections are uncommonPIP: Respiratory syncytial virus (RSV) is a well-recognized cause of lower respiratory tract infections during early childhood in industrialized countries . The study of 4 RSV infection outbreaks which occurred during 1993-96 in The Gambia led to the identification of RSV infection in 574 children through the immunofluorescent staining of nasopharyngeal aspirate samples among children of median age 3-8 months who presented with respiratory infections at 3 hospitals in the Western region of the country . 13 children had conditions thought to increase the risk of severe RSV infection, with crepitations heard during physical examinations in 80% of children admitted to the hospital and wheezes heard in 39% . 80 children were given oxygen because of hypoxemia . 9 of 255 blood cultures were positive for the following pathogens: 4 Streptococcus pneumoniae, 2 Haemophilus influenzae type b, 2 Staphylococcus aureus, and 1 Enterobacter agglomerans . 13 children died . 90% of isolates typed during year 1 were RSV subgroup A, 25% in the second year of study, 75% in year 3, and 95% in year 4 . These findings demonstrate that RSV is a significant cause of lower respiratory tract infection in young children in The Gambia, causing epidemics of bronchiolitis . It is most likely cost-effective to prevent RSV infection through vaccination .

J Antimicrob Chemother, 1998 Feb, 41(2), 247 - 51
Can susceptibility to an antimicrobial be restored by halting its use? The case of streptomycin versus Enterobacteriaceae; Chiew YF et al.; To test the widespread view that resistance disappears in the absence of antimicrobial use, we tested streptomycin against 477 Enterobacteriaceae from the Royal London Hospital . Twenty per cent proved resistant although streptomycin is little used at the hospital and streptomycin resistance in gram-negative bacteria is caused by mechanisms that do not compromise the drugs that are used . Up to 70% of the observed resistance was associated with cross-resistance to spectinomycin and the presence of ant(3")-Ia, an integron-associated gene carried in Tn21-type transposons . This genetic organization may have conserved streptomycin resistance in the absence of direct selection pressure.

Ann Pharmacother, 1998 Mar, 32(3), 320 - 36
Levofloxacin and sparfloxacin: new quinolone antibiotics; Martin SJ et al.; OBJECTIVE: To discuss the pharmacology, pharmacokinetics, spectrum of activity, clinical trials, and adverse effects of levofloxacin and sparfloxacin, two new fluoroquinolone antibiotics . DATA SOURCES: Literature was identified by a MEDLINE search from January 1985 to September 1997 . Abstracts and presentations were identified by review of program abstracts from the Interscience Conference on Antimicrobial Agents and Chemotherapy from 1988 to 1996 . STUDY SELECTION: Randomized, controlled clinical studies were selected for evaluation; however, uncontrolled studies were included when data were limited for indications approved by the Food and Drug Administration (FDA) . In vitro data were selected from comparison trials whenever available . Only in vitro trials that provided data on the minimum inhibitory concentrations required to inhibit 90% of isolates were used . Data from North American studies were selected whenever available . DATA EXTRACTION: Data were evaluated with respect to in vitro activity, study design, clinical and microbiologic outcomes, and adverse drug reactions . DATA SYNTHESIS: Levofloxacin and sparfloxacin are active against pathogens frequently involved in community-acquired upper and lower respiratory tract infections, including Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Mycoplasma pneumoniae, Legionella pneumophila, and Chlamydia pneumoniae . Both compounds have enhanced activity compared with ciprofloxacin against most gram-positive bacteria, including enterococci, streptococci, and staphylococci, and retain good activity against most Enterobacteriaceae and Pseudomonas aeruginosa . Sparfloxacin has greater anaerobic activity than levofloxacin, which is more active than ciprofloxacin or ofloxacin . Although many clinical studies are available only in abstract form, the clinical data demonstrate that these new quinolones are effective for most community-acquired upper and lower respiratory tract infections, urinary tract infections, gonococcal and nongonococcal urethritis, and skin and skin structure infections . FDA-approved indications are limited for both compounds to date . CONCLUSIONS: Levofloxacin and sparfloxacin have improved gram-positive activity compared with that of older fluoroquinolones, and are administered once daily . Sparfloxacin-associated photosensitivity may limit its therapeutic usefulness . Clinical trials confirm that these agents are as effective as traditional therapies for the management of community-acquired pneumonia, acute exacerbations of chronic bronchitis, sinusitis, urinary tract infections, acute gonococcal and nongonococcal urethritis, and skin and skin structure infections.

Zh Mikrobiol Epidemiol Immunobiol, 1998 Jan-Feb, (1), 3 - 6
{An experimental model of enteric klebsiellosis}; Bondarenko VM et al.; Acute enteric infection was reproduced in rabbits, used as an experimental model, receiving Aspergillus flavus metabolites with food for 15 days and inoculated rectally with enterotoxigenic strain Klebsiella pneumoniae K24 6723 . Pathomorphological study revealed the penetration of Klebsiella into microplicate cells of the intestinal epithelium, the proliferation of bacteria in the lamina propria and in the cupolas of Peyer's patches, as well as in phagolysosomes of leukocytes and macrophages . The lesion of the mucous membrane in both large and small intestine, accompanied by the hyperplasia of lymphoid follicles, was noted . As a rule, surface epithelium was dystrophically changed and peeled off into the lumen of the intestine . The specificity of such lesion was confirmed by the detection of Klebsiella in Coons' direct immunofluorescence test . The experimental model confirmed the role of a decrease in immunological protective reactions of the body, caused the action of A.flavus metabolites, in the development of the infectious process, initiated by opportunistic enterobacteria.

Vet Clin North Am Food Anim Pract, 1998 Mar, 14(1), 17 - 29
Microbial food borne pathogens . Salmonella; Ekperigin HE et al.; All food animals are susceptible to infection with Salmonella, a genus of gram negative, nonspore-forming, usually motile, facultative anaerobic bacilli belonging to the family Enterobacteriaceae . Salmonella are differentiated into over 2200 serologically distinct types (serotypes) based on differences in somatic, flagellar, and capsular antigens . Infection with Salmonella may or may not lead to a sometimes fatal salmonellosis, a disease that can remain localized in the gastrointestinal tract as gastro-enteritis, or become generalized as a septicemia and affect several organ systems . Infected food animals that do not develop salmonellosis, and those that recover from the disease, become carriers of Salmonella and serve as sources of infection to humans and other animals . Apart from being a source of Salmonella food poisoning for humans, Salmonella-contaminated food animal carcasses are also a concern because they are a source of antibiotic-resistant Salmonella.

J Chemother, 1998 Feb, 10(1), 35 - 46
Pneumonia: the impact of risk factors on the outcome of treatment with meropenem and ceftazidime; Finch RG et al.; This analysis comprises data pooled from two clinical trials of meropenem (0.5 g 8-hourly) versus ceftazidime (1 g 8-hourly) in hospitalized patients with community-acquired pneumonia . The clinical and bacteriological responses to treatment were assessed in relation to a range of risk factors previously linked to a poor clinical outcome . 393 patients (198 meropenem, 195 ceftazidime) were clinically evaluable while 230 (113 meropenem, 117 ceftazidime) were bacteriologically evaluable . Meropenem was highly effective, independent of associated risk factors, producing overall satisfactory clinical and bacteriological response rates at the end of therapy of 91.4% and 94.7%, respectively, similar to those produced by ceftazidime (90.3% and 92.3%, respectively) . Clinical and bacteriological treatment outcome were similar in patients with up to three of the following key risk factors: age > or =65 years, male gender, serum urea >7 mmol/L, serum albumin <35 g/L and difficult-to-treat pathogens . Meropenem also achieved high clinical (85.7%) and bacteriological (89.3%) success rates in patients requiring ventilation, as did ceftazidime (81.6% and 87.1%, respectively) . Both agents were highly effective against both Gram-negative and Gram-positive causative pathogens, including those organisms normally considered difficult to treat and typical of nosocomial pneumonia (e.g . Enterobacteriaceae, Staphylococcus aureus, Pseudomonas aeruginosa) . Thus, meropenem and ceftazidime were highly effective in patients hospitalized with community-acquired pneumonia, irrespective of a number of concurrent risk factors (including those regarded as key risk factors) . Furthermore, the analysis points to a role for meropenem 0.5 g 8-hourly in the treatment of nosocomial pneumonias that do not require intensive care unit admission and/or mechanical ventilation . Overall, this novel analysis of trial data suggests that incorporation of key risk factor endpoints into the initial design of pneumonia studies may prove to be a useful approach in defining appropriate antibiotic treatment for specific patient groups.

Semin Immunol, 1998 Feb, 10(1), 15 - 23
Unraveling the mystery of HLA-B27 association with human spondyloarthropathies using transgenic and knock out mice; Khare SD et al.; Human spondyloarthropathies have a strong association with the presence of MHC class I allele, HLA-B27 . Spondyloarthropathies occur predominantly in males and are usually triggered by an infection with an enterobacteria . Similar to human disease, experimental animals with HLA-B27 transgene also develop spontaneous inflammatory disease . In addition to HLA-B27, the role of environmental antigens has also been implicated in the animal models . How bacteria interact with HLA-B27 is not yet clearly understood . By breeding HLA-B27 transgenic mice with various transgenic and knock out mice, we investigated the immune mechanism in this inflammatory disease . In this review, we will summarize our recent findings and propose a hypothesis.

Antimicrob Agents Chemother, 1998 Feb, 42(2), 425 - 7
Concentrations of pefloxacin in plasma and tissue after administration as surgical prophylaxis; Jacoberger B et al.; Plasma and epiploic-fat drug concentrations determined by high-performance liquid chromatography and fat penetration of pefloxacin and its metabolite (norfloxacin) given for antimicrobial prophylaxis were studied in patients scheduled for colorectal surgery . Concentrations of pefloxacin in plasma decreased about 40% from the beginning of the operation to closure of the peritoneum, and corresponding levels in epiploic fat stayed stable . The plasma and tissue norfloxacin concentrations were very low . Concentrations of pefloxacin in tissue were greater than MIC at which 90% of isolates are inhibited for sensitive bacteria (members of the family Enterobacteriaceae) . The penetration of pefloxacin into epiploic fat was about 32%.

Plant Foods Hum Nutr, 1997, 51(2), 145 - 57
An evaluation of the microflora associated with fermented African oil bean (Pentaclethra macrophylla Bentham) seeds during ugba production; Isu NR et al.; The microorganisms associated with fermented African oil bean (Pentaclethra macrophylla Bentham) seed during ugba production was studied . Only bacteria were isolated from the ugba samples used . Although the bacteria included Bacillus spp., Lactobacillus spp., Staphylococcus spp., Micrococcus spp . and members of the family Enterobacteriaceae, only the Bacillus spp . were found to ferment African oil bean seeds to ugba . Bacillus spp . were the predominant microorganisms present, constituting over 95% of the total microbial population density . An increase in the number of Bacillus cells of about 2 log units daily, which attained a maximum density of log10 9.00 - log10 11.90 cfu/g after 3 days was observed . Contrarily, the Lactobacillus spp . increased minimally and attained a maximum value of log10 4.20 - log10 6.35 cfu/g within the same period . The Staphylococcus spp., Micrococcus spp . and the members of the family Enterobacteriaceae remained fairly steady in number for 24h, increased slightly till the 3rd day followed by exponential increases which attained maximum values of between log10 9.20 - log10 11.00, about the 7th day . Bacillus spp . cells also had the highest protease activities which were significantly (p < 0.05) higher than the values for the other bacterial isolates . The Bacillus spp . responsible for the fermentation of African oil bean seeds to ugba were identified as Bacillus coagulans, B . macerans, B . megaterium, B . pumilis and B . subtilis.

Plant Foods Hum Nutr, 1997, 51(2), 125 - 35
Date bars fortified with almonds, sesame seeds, oat flakes and skim milk powder; Al-Hooti S et al.; Fortified date bars were prepared from some of the commonly grown date cultivars in the United Arab Emirates . The average ash, fat and protein contents in the control date bar sample were 1.78, 6.09 and 7.83%, respectively . The ash and protein contents increased, but the fat content decreased slightly with the inclusion of skim milk powder in the remaining date bar formulations . All the date bar samples were found to be free from Enterobacteriaceae and coliforms . Date fruit, which usually supplies only calories, can thus be turned into a product having significant amounts of other valuable nutrients.

Perit Dial Int, 1998 Jan-Feb, 18(1), 41 - 5
Risk factors for developing peritonitis caused by micro-organisms of enteral origin in peritoneal dialysis patients; Caravaca F et al.; OBJECTIVE: To investigate the risk factors associated with the development of peritonitis caused by enteral bacteria in peritoneal dialysis patients, including the prescription of gastric acid inhibitors as a potential risk factor . DESIGN: Retrospective single-center study . SETTING: Tertiary university hospital . PATIENTS AND MAIN OUTCOME MEASURES: Fifty-five patients who entered into our continuous ambulatory peritoneal dialysis (CAPD) program during the last 6 years were included . Multiple logistic regression analysis was used to establish the best determinants over the development of at least one episode of enteric peritonitis . The predictive variables included in the model were: age, gender, diabetic versus nondiabetic, polycystic versus nonpolycystic kidney diseases, history of constipation, presence or absence of moderate/severe malnutrition, peritoneal transport characteristics, peritoneal protein losses, rate of exit-site infections, rate of total peritonitis, intestinal abnormalities, and treatment with inhibitors of gastric acid secretion . RESULTS: The total number of peritonitis episodes during the studied period was 88, which clustered in 34 of 55 patients . Fourteen (16%) were caused by enteric micro-organisms in 10 patients: Escherichia coli (6), Klebsiella sp (2), Enterobacter sp (1), and Enterococcus sp (5) . Nine of 10 patients who developed enteric peritonitis were on gastric acid inhibitors (3 patients on omeprazole and 6 patients on H2-antagonists), while 15 of 45 patients who did not develop enteric peritonitis were on gastric acid inhibitors (all of them on H2-blockers) . There were temporal relationships between the start of gastric acid inhibitors and the development of enteric peritonitis in 6 of 9 patients who were on this medication . Four of 10 patients who developed enteric peritonitis had diverticulosis . Ten of 45 patients who did not develop enteric peritonitis had been diagnosed with diverticulosis of the colon or sigmoid prior to entry to CAPD . The unique patient who was not on gastric acid inhibitors and developed enteric peritonitis, had been diagnosed with chronic atrophic gastritis with achlorhydria . By multiple logistic regression analysis, the treatment with gastric acid inhibitors was the only independent variable that entered into the best predictive equation over the development of enteric peritonitis (log likelihood ratio = -26.077, odds ratio = 18; 95% CI odds ratio: 2 - 155) . CONCLUSION: Gastric acid inhibitors may increase the risk for developing enteric peritonitis in peritoneal dialysis patients.

Eur J Biochem, 1998 Mar 1, 252(2), 299 - 304
Primary cause of mortality in the armyworm larvae simultaneously parasitized by parasitic wasp and infected with bacteria; Matsumoto H et al.; Parasitoid wasps never kill their hosts before the wasp larvae emerge from the host . However, almost 100% of the host armyworm larvae Pseudaletia separata die within 2-3 days by parasitization with the wasp Cotesia kariyai or by injection of polydnavirus, the wasp symbiont virus, when they are simultaneously infected by the pathogenic bacterium Serratia marcescens . The present study was conducted to elucidate the crucial factor causing this larval mortality . An insecticidal protein has been shown to exist in the hemolymph of dying host larvae; it has been purified by procedures consisting of reverse-phase column extraction, gel filtration and ion-exchange column chromatography . The purified protein showed a strong insecticidal effect with a median lethal dosage (LD50) of 13 pmol/larva and was estimated to have a molecular mass of 57 kDa . The amino acid sequence of the insecticidal protein was partially characterized and used for isolation and sequencing of the genomic DNA . The deduced amino acid sequence for this protein revealed striking similarity with the metalloprotease of S . marcescens enterobacter.

Pol Merkuriusz Lek, 1997 Dec, 3(18), 264 - 8
{Occurrence and susceptibility of hospital strains producing enzymes with a wide spectrum of substrate profiles}; Goras-Zawiazalec A et al.; In connection with more and more frequent occurrence of extended spectrum beta-lactamases an effort has been made to detect their presence in the biological materials coming from the patients of different wards of Mining Hospital in Sosnowiec from January to September 1995 . Among 38 diagnostic materials, from which the strains in question were isolated, the following materials have been examined: bronchial lavage (52.6%), surgical wounds (18.4%), urines (15.8%) and others (13.2%) . The examined diagnostic materials came from Intensive Care Unit (87.0%), Casualty and Orthopaedic Surgery Clinic (5.0%) and General Surgery Clinic (3.0%) . The most frequently isolated microorganisms were Klebsiella pneumoniae . (47.4%), Serratia marcescens (36.8%), Enterobacter cloacae (10.5%) and others (5.3%) . Half of the examined strains constituted those producing extended spectrum beta-lactamases and probably possessing an extra resistance mechanism: (Serratia marcescens--74%, Enterobacter cloacae--21%, Enterobacter aerogenes--5.0%) and 50% were those producing extended--spectrum beta-lactamases . (Klebsiella pneumoniae--95%, Escherichia coli--5%) . Susceptibility of the examined strains to anti-microbial antibiotics was diverse . Full susceptibility of the analysed strains has been observed exclusively in case of Karbapenems (Imipenem, Meropenem and Cefamycyn) . In case of beta-lactamase with beta-lactamase inhibitor combinations susceptibility was diverse and dependent on the species of the examined microorganism.

Clin Orthop, 1998 Feb, (347), 131 - 7
Clinical and functional outcomes of internal fixation of displaced pilon fractures; Sands A et al.; The clinical and functional outcomes for patients treated with open reduction and plate fixation of displaced tibial pilon fractures were determined . A retrospective search of the authors' trauma database was conducted for AO and Orthopaedic Trauma Association Code 43 injuries (pilon fractures) in adults 18 years or older who were treated between December 1988 and December 1992 . The group of 64 patients who required open reduction and internal fixation to treat their fractures make up the primary cohort for this analysis . Twenty of these cases required no fibular fixation; the remainder were mostly fixed with 1/3 tubular or 3.5-mm compression plates . Tibial fixation was done using most commonly 3.5-mm cloverleaf plates, 1/3 tubular plates, or both . Of the 64 patients treated with open reduction and internal replacement, four (5%) patients had deep infection develop . Two (7%) of 14 patients had open fractures, and two (4%) of 50 patients had closed fractures . Three of these four patients smoked tobacco products; one was also an intravenous drug abuser . Staphylococcus aureus was the organism in two cases; Enterobacter, in the other two . The infection was controlled with a free flap in two cases, with antibiotics and wound debridement in one and with an arthrodesis in one . Thirty of the 64 patients completed the Short Form-36; two of these patients had bilateral fractures . The study group had significant differences in general health perceptions, physical function, physical role function, emotional role function, social and mental function, and pain and energy levels when compared with age matched population data and patients with tibial plateau fractures . The effect of other injuries on these functional status results cannot be determined specifically.

Lancet, 1998 Mar 14, 351(9105), 797 - 9
Quinolone resistance from a transferable plasmid; Martinez-Martinez L et al.; BACKGROUND: Bacteria can mutate to acquire quinolone resistance by target alterations or diminished drug accumulation . Plasmid-mediated resistance to quinolones in clinical isolates has been claimed but not confirmed . We investigated whether a multiresistance plasmid could transfer resistance to quinolones between bacteria . METHODS: We transferred resistance between strains by conjugation . The resistance plasmid was visualised in different hosts by agarose-gel electrophoresis . We determined the frequency of spontaneous mutations to ciprofloxacin or nalidixic-acid resistance in Escherichia coli strains, with or without the quinolone resistance plasmid . FINDINGS: A multiresistance plasmid (pMG252) from a clinical isolate of Klebsiella pneumoniae was found to increase quinolone resistance to minimum inhibitory concentrations (MICs) as high as 32 microg/mL for ciprofloxacin when transferred to strains of K pneumoniae deficient in outer-membrane porins . Much lower resistance was seen when pMG252 was introduced into K pneumoniae or E coli strains with normal porins . The plasmid had a wide host range and expressed quinolone resistance in other enterobacteriaceae and in Pseudomonas aeruginosa . From a plasmid-containing E coli strain with ciprofloxacin MIC of 0.25 microg/mL and nalidixic-acid MIC of 32 microg/mL, quinolone-resistant mutants could be obtained at more than 100 times the frequency of a plasmid-free strain, reaching MICs for ciprofloxacin of 4 microg/mL and for nalidixic acid of 256 microg/mL . INTERPRETATION: Transferable resistance to fluoroquinines and nalidixic acid has been found in a clinical isolate of K pneumoniae on a broad host range plasmid . Although resistance was low in wild-type strains, higher levels of quinolone resistance arose readily by mutation . Such a plasmid can speed the development and spread of resistance to these valuable antimicrobial agents.

Antimicrob Agents Chemother, 1998 Mar, 42(3), 596 - 600
Plasmid-mediated resistance to expanded-spectrum cephalosporins among Enterobacter aerogenes strains; Pitout JD et al.; Resistance to expanded-spectrum cephalosporins commonly develops in Enterobacter aerogenes during therapy due to selection of mutants producing high levels of the chromosomal Bush group 1 beta-lactamase . Recently, resistant strains producing plasmid-mediated extended-spectrum beta-lactamases (ESBLs) have been isolated as well . A study was designed to investigate ESBL production among 31 clinical isolates of E . aerogenes from Richmond, Va., with decreased susceptibility to expanded-spectrum cephalosporins and a positive double-disk potentiation test . Antibiotic susceptibility was determined by standard disk diffusion and agar dilution procedures . Beta-lactamases were investigated by an isoelectric focusing overlay technique which simultaneously determined isoelectric points (pIs) and substrate or inhibitor profiles . Decreased susceptibility to cefotaxime, ceftazidime, and aztreonam (MIC range, 1 to 64 microg/ml) was detected and associated with resistance to gentamicin and trimethoprim-sulfamethoxazole . All strains produced an inducible Bush group 1 beta-lactamase (pI 83) . Twenty-nine of the 31 isolates also produced an enzyme similar to SHV-4 (pI 7.8), while 1 isolate each produced an enzyme similar to SHV-3 (pI 6.9) and to SHV-5 (pI 8.2) . The three different SHV-derived ESBLs were transferred by transconjugation to Escherichia coli C600N and amplified by PCR . Plasmid profiles of the clinical isolates showed a variety of different large plasmids . Because of the linkage of resistance to aminoglycosides and trimethoprim-sulfamethoxazole with ESBL production, it is possible that the usage of these drugs was responsible for selecting plasmid-mediated resistance to extended-spectrum cephalosporins in E . aerogenes . Furthermore, it is important that strains such as these be recognized, because they can be responsible for institutional spread of resistance genes.

Antimicrob Agents Chemother, 1998 Mar, 42(3), 514 - 20
Ceftazidime-resistant Enterobacteriaceae isolates from three Polish hospitals: identification of three novel TEM- and SHV-5-type extended-spectrum beta-lactamases; Gniadkowski M et al.; Twelve ceftazidime-resistant isolates of the family Enterobacteriaceae (11 Klebsiella pneumoniae isolates and 1 Escherichia coli isolate) were collected in 1995 from three Polish hospitals located in different cities . All were identified as producers of extended-spectrum beta-lactamases (ESBLs) . Detailed analysis of their beta-lactamase contents revealed that six of them expressed SHV-5-like ESBLs . The remaining six were found to produce three different TEM enzymes, each characterized by a pI value of 6.0 and specified by new combinations of amino acid substitutions . The amino acid substitutions compared to the TEM-1 beta-lactamase sequence were Gly238Ser, Glu240Lys, and Thr265Met for TEM-47; Leu21Phe, Gly238Ser, Glu240Lys, and Thr265Met for TEM-48; and Leu21Phe, Gly238Ser, Glu240Lys, Thr265Met, and Ser268Gly for TEM-49 . The new TEM beta-lactamases, TEM-47, TEM-48, and TEM-49, belong to a subfamily of TEM-2-related enzymes . Genes coding for TEM-47 and TEM-49 could have originated from the TEM-48-encoding sequence by various single genetic events . The new TEM derivatives probably document the already advanced microevolution of ESBLs ongoing in Polish hospitals, in a majority of which no monitoring of ESBL producers was performed before 1996.

J Clin Pathol, 1997 Dec, 50(12), 1027 - 8
Resistance to ciprofloxacin in pathogenic Enterobacteriaceae in England and Wales in 1996; Threlfall EJ et al.; In 1996, 6% of Escherichia coli from extraintestinal infections were resistant to ciprofloxacin with minimum inhibitory concentrations (MICs) > or = 2 mg/l (high level resistance) . Low level resistance (MIC 0.125-1 mg/l) was also identified in 7% of Salmonella typhi, 4% of S paratyphi A, and 4% of non-typhoidal salmonellas . However, resistance to ciprofloxacin was rarely identified in shigellas . For E coli, physicians should be aware that treatment failures may occur when patients with invasive illness are treated with ciprofloxacin before the results of laboratory sensitivity tests are available . For salmonellas an increasing number of treatment failures have been recorded for patients infected with strains with low level resistance . Because of the increasing incidence of Enterobacteriaceae with low level resistance to ciprofloxacin, it is recommended that for this group of organisms a breakpoint of 0.125 mg/l should be included in laboratory sensitivity tests.

J Bacteriol, 1998 Mar, 180(6), 1586 - 91
The folate branch of the methionine biosynthesis pathway in Streptomyces lividans: disruption of the 5,10-methylenetetrahydrofolate reductase gene leads to methionine auxotrophy; Blanco J et al.; In enterobacteria, the methyl group of methionine is donated by 5-methyltetrahydrofolate that is synthesized from N5,10-methylenetetrahydrofolate by the 5,10-methylenetetrahydrofolate reductase . The Streptomyces lividans metF gene, which encodes 5,10-methylenetetrahydrofolate reductase, has been cloned . It encodes a protein of 307 amino acids with a deduced molecular mass of 33,271 Da . S1 exonuclease mapping of the transcription initiation site showed that the metF gene is expressed, forming a leaderless mRNA . A 13-bp tandem repeat located immediately upstream of the promoter region shows homology with the consensus MetR-binding sequence of Salmonella typhimurium . Expression of metF in multicopy plasmids in S . lividans resulted in accumulation of a 32-kDa protein, as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis . Disruption of the metF gene led to methionine auxotrophy . Integration of the disrupting plasmid at the metF locus was confirmed by Southern hybridization in three randomly isolated transformants . The methionine auxotrophy was complemented by transformation of the auxotrophs with an undisrupted metF gene . These results indicate that the folate branch is essential for methionine biosynthesis in streptomycetes, as occurs in enterobacteria.

J Bacteriol, 1998 Mar, 180(6), 1446 - 53
IroN, a novel outer membrane siderophore receptor characteristic of Salmonella enterica; Baumler AJ et al.; Speciation in enterobacteria involved horizontal gene transfer . Therefore, analysis of genes acquired by horizontal transfer that are present in one species but not its close relatives is expected to give insights into how new bacterial species were formed . In this study we characterize iroN, a gene located downstream of the iroBC operon in the iroA locus of Salmonella enterica serotype Typhi . Like iroBC, the iroN gene is present in all phylogenetic lineages of S . enterica but is absent from closely related species such as Salmonella bongori or Escherichia coli . Comparison of the deduced amino acid sequence of iroN with other proteins suggested that this gene encodes an outer membrane siderophore receptor protein . Mutational analysis in S . enterica and expression in E . coli identified a 78-kDa outer membrane protein as the iroN gene product . When introduced into an E . coli fepA cir fiu aroB mutant on a cosmid, iroN mediated utilization of structurally related catecholate siderophores, including N-(2,3-dihydroxybenzoyl)-L-serine, myxochelin A, benzaldehyde-2,3-dihydroxybenzhydrazone, 2-N,6-N-bis(2,3-dihydroxybenzoyl)-L-lysine, 2-N,6-N-bis(2,3-dihydroxybenzoyl)-L-lysine amide, and enterochelin . These results suggest that the iroA locus functions in iron acquisition in S . enterica.

J Nat Prod, 1998 Feb, 61(2), 262 - 3
Transtorine, a new quinoline alkaloid from Ephedra transitoria; al-Khalil S et al.; Transtorine (1), a new quinoline alkaloid, isolated from the aerial part of Ephedra transitoria by column chromatography, was identified as 4-quinolone-2-carboxylic acid . The structure was determined by spectroscopic methods . Transtorine exhibited growth inhibitory activity against the common bacteria, Enterobacter cloacae, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus.

Electrophoresis, 1998 Jan, 19(1), 66 - 70
DNA fingerprinting of Listeria monocytogenes using enterobacterial repetitive intergenic consensus (ERIC) motifs-polymerase chain reaction/capillary electrophoresis; Sciacchitano CJ; The molecular technique, enterobacterial repetitive intergenic consensus (ERIC)-polymerase chain reaction (PCR) produces genomic DNA fingerprint that discriminate bacterial species and strains . This technique was applied to the characterization of Listeria monocytogenes, an important food-borne pathogen implicated in numerous cases of listeriosis . The ERIC-PCR resulted in distinct DNA fingerprinting patterns of all L . monocytogene serotypes and Listeria species . Analysis of the genomic DNA fingerprints was accomplished using capillary electrophoresis (CE), an alternative technique to the conventional agarose gel method . The optimization of CE conditions (electrokinetic injection, applied voltage) resulted in the resolution of amplified DNA fragments up to 1000 bp . Comparisons of electropherograms provided genomic fingerprint templates which could be further used for supplementary information . The ERIC-PCR method coupled to CE provides a rapid technique in differentiating bacterial spp., and may contribute relevant information in food-borne outbreak studies.

J Med Microbiol, 1998 Mar, 47(3), 227 - 34
Characterisation of diarrhoeagenic Escherichia coli clones by ribotyping and ERIC-PCR; Dalla-Costa LM et al.; The ability of ribotyping and enterobacterial repetitive intergenic concensus-polymerase chain reaction (ERIC-PCR) to discriminate diarrhoeagenic Escherichia coli clones of 122 strains belonging to 26 distinct serotypes was evaluated . The 26 serotypes corresponded to 24 ribotypes and 25 ERIC-types . Correlation between multilocus enzyme electrophoresis, ERIC-PCR and ribotyping was c . 90% for the dominant ribotypes . Related clones such as O55:H7 and O157:H7 presented similar ribotypes and clustered together in a dendrogram, and the two divergent clonal groups of enteropathogenic E . coli (EPEC) and enterohaemorrhagic E . coli (EHEC) were included in distinct branches . The results suggest the possibility of applying these two simpler techniques as tools to identify clones of diarrhoeagenic E . coli.

Dig Dis Sci, 1998 Jan, 43(1), 138 - 47
Evaluation of fructooligosaccharide supplementation of oral electrolyte solutions for treatment of diarrhea: recovery of the intestinal bacteria; Oli MW et al.; Although oral electrolyte solutions (OES) replenish salts and water lost during diarrhea, present formulations do not address disturbances of the normal intestinal microbiota . Therefore, we evaluated the efficacy of an OES with and without fructooligosaccharide (FOS) for treatment of pigs with acute secretory diarrhea induced by cholera toxin . Before, during, and after diarrhea, bacteriologic evaluation was made of contents collected from the mid small intestine, cecum, and distal colon and mucosa scraped from the mid small intestine . Diarrhea caused significant declines in total bacterial counts of contents from all three regions, with less of an impact on bacteria associated with the mucosa . Although total bacterial counts recovered within 24 hr, regardless of treatment, densities of Enterobacteriaceae were higher in pigs treated with OES whereas those receiving FOS had more lactobacilli . Our results show that secretory diarrhea disturbs the normal densities and relative species abundance of the microbiota, with the influences more pronounced for contents relative to the mucosa, and that adding FOS to OES accelerates the recovery of bacteria perceived as beneficial while potentially slowing the recovery of pathogenic forms.

J Clin Microbiol, 1998 Mar, 36(3), 814 - 7
PCR methods for rapid identification and characterization of Actinobacillus seminis strains; Appuhamy S et al.; Twenty-four isolates of Actinobacillus seminis were typed by PCR ribotyping, repetitive extragenic palindromic element (REP)-based PCR, and enterobacterial repetitive intergenic consensus (ERIC)-based PCR . Five types were distinguished by REP-PCR, and nine types were distinguished by ERIC-PCR . PCR ribotyping produced the simplest pattern and could be useful for identification of A . seminis and for its differentiation from related species . REP- and ERIC-PCR could be used for strain differentiation in epidemiological studies of A . seminis.

J Clin Microbiol, 1998 Mar, 36(3), 657 - 61
Controlled clinical laboratory comparison of two supplemented aerobic and anaerobic media used in automated blood culture systems to detect bloodstream infections; Ziegler R et al.; A 20-ml blood sample was collected from adult patients with suspected bloodstream infections and distributed equally into the four volume-controlled bottles of a blood culture set consisting of aerobic and anaerobic BACTEC Plus/F bottles and aerobic and anaerobic BacT/Alert FAN bottles . All bottles were incubated in their respective instruments for a standard 5-day protocol or until the instruments signalled positivity . Samples in all bottles with negative results by these instruments were terminally subcultured . A total of 8,390 blood culture sets were obtained during the study period, of which 4,402 (52.5%) met the study criteria . Of these, 946 (21.5%) were positive either by instrument signal or by additional terminal subculture of all negative bottles and yielded growth of microorganisms . Five hundred eighty-nine (13.4%) blood culture sets were considered to have recovered 663 clinically significant organisms . When both the BACTEC and the BacT/Alert systems were used, 465 positive sets were detected; BACTEC alone detected 52 positive sets and BacT/Alert alone detected 72 (P = 0.09) . No differences were found between the two systems in microbial recovery rate from blood cultures obtained from patients on antibiotic therapy . Significantly more members of the family Enterobacteriaceae (P < 0.01) were detected from patients without antimicrobial therapy by BacT/Alert than by BACTEC . The false-negative rates were 0.20% for BACTEC and 0.32% for BacT/Alert . A significantly higher false-positive rate was found for BACTEC (P < 0.0001) . Both systems were comparable for the time to detection of microorganisms . However, gram-positive bacteria were detected faster by BACTEC and Enterobacteriaceae were detected faster on average by BacT/Alert . We concluded that both systems are comparable in their abilities to recover aerobic and anaerobic organisms from blood cultures and a terminal subculture might not be necessary for either of the two systems . The increased positivity rate when using an anaerobic bottle in a two-bottle blood culture set is due to the additional blood volume rather than to the use of an anaerobic medium.

Rev Sci Tech, 1997 Aug, 16(2), 452 - 71
{Pathogenic organisms in milk and milk products: the situation in France and in Europe}; Brisabois A et al.; Milk and dairy products harbour a natural microbial flora and/or other micro-organisms, which vary within the wide range of products available on the French market . The origin of contamination by pathogenic bacteria varies with the type of product and the mode of production and processing . Contamination of milk and dairy products by pathogenic micro-organisms can be of endogenous origin, following excretion from the udder of an infected animal . Contamination may also be of exogenous origin, through direct contact with infected herds or through the environment (e.g . water, personnel) . Treatment and processing of milk can inhibit or encourage the multiplication of micro-organisms . The authors describe the relevant aspects of bacterial physiology and ecology, the occurrence of bacteria in dairy products, and the public health significance for each of the principal micro-organisms found in such products . Bacteria most frequently involved are mycobacteria, Brucella sp., Listeria monocytogenes, Staphylococcus aureus and enterobacteria (including toxigenic Escherichia coli and Salmonella) . At present, systems of testing and surveillance are required for the control of pathogenic bacteria in milk and dairy products, as specified by regulations currently being developed for all countries in the European Union . Preventive measures should take into account the well-established facts concerning the potential microbiological impact of pathogenic bacteria on milk and dairy products . There should be increased recourse to risk analysis methods to assess the threat to the consumer with regard to the presence of pathogenic bacteria in food.

Anasthesiol Intensivmed Notfallmed Schmerzther, 1997 Nov, 32(11), 699 - 702
{Multiple organ failure with several weeks' persistence of ARDS: successful therapy with methylprednisolone}; Jellinek H et al.; A 21-year-old female who had developed ileus underwent abdominal surgery for adhesiolysis . Because of postoperative bleeding she required repeated surgical reexploration . Subsequently, the patient developed abdominal sepsis (Enterobacter cloacae) and, on day 11 of mechanical ventilation, severe adult respiratory distress syndrome (ARDS) (Lung injury score 3.5, paO2/FiO2 55 mmHg) . Despite clearing the abdominal situation, chest films showed persisting and new pulmonary infiltrates, leucocytosis, fever and purulent bronchial secretion occurring over a period of five weeks . Despite aggressive antibiotic treatment the patient deteriorated further and disease progressed to multiple organ dysfunction syndrome . At the beginning of week six all bacteriological specimens (blood, bronchoalveolar lavage, urine, catheter tips) were negative for potential pathogens . Possible extrapulmonary infection sites were cleared by computed tomography and Tc 99 labeled antigranulocyte antibody scan . Open lung biopsy was performed on day 33 of ARDS and revealed severe diffuse alveolar damage in the fibroproliferative phase of ARDS . On day 37 after ARDS onset, antibiotic treatment was discontinued and methyl-prednisolone (32 mg every 6 hours, 2.5 mg/kg.day) was started . After five days a significant improvement of pulmonary function (lung injury score decreased from 3.5 to 2.5, paO2/FiO2 increased from 82 to > 200 mmHg) and of cardiovascular performance occurred . Corticosteroid treatment was continued for 29 days and was complicated by an episode of pneumonia (Klebsiella pneumoniae) requiring antibiotic therapy . The patient's trachea was successfully extubated on day 80 . She was discharged from intensive care unit on day 93 and left hospital three weeks later . We conclude that late ARDS may cause systemic inflammatory response and persisting organ dysfunction without an identifiable source of infection . Corticosteroid therapy might improve fibroproliferative changes of the lung even if instituted weeks after the onset of ARDS.

New Microbiol, 1998 Jan, 21(1), 31 - 40
The influence of the SOS response on the activity of 4-quinolones and zidovudine against some strains of Enterobacteria; Mascellino MT et al.; The 4-Quinolones are known to induce the SOS response . This should also be the case with AZT (Zidovudine) which has the same bactericidal mechanism . SOS response might make the bacteria more sensitive or more resistant to subsequent doses of quinolones and AZT . NA (Nalidixic acid), the first quinolone of the early 1960s, sensitises a strain of E . coli isolated from the urine of patients with cystopyelitis and the E . coli AB1157 wild type strain which is a well-known SOS inducer . In this case, the SOS system is not involved but only the recombination repair mechanisms which make the bacteria more susceptible to further damage by NA . On the contrary, CPX (Ciprofloxacin) protects E . coli from further exposure to antibiotics . Therefore the SOS response induction assists the bacteria in recovering from the DNA damage caused by CPX . The SOS response induced by AZT in the tested E . coli strains does not seem to either contribute to the lethality of the drug or to be involved in protecting bacteria from the damage caused by AZT . In fact, the percentage of killing was the same for both pre-treated and non pre-treated bacteria (p = 0.5) . On the contrary, it was found that in Salmonella typhimurium belonging to blood of a patient with recurrent bacteriaemia, the CPX added to pre-treated bacteria with AZT was less lethal than when it was added to non pre-treated bacteria . The SOS response, in this case, protects bacteria from the damage caused by AZT.

Rev Med Chil, 1997 May, 125(5), 544 - 51
{Salmonella enteritidis, an emergent pathogen in Chile}; Fica A et al.; BACKGROUND: Salmonella enteritidis infections have increased worldwide in the last years . Isolation of this pathogen was remarkably rare in Chile until 1994, when the still ongoing outbreak emerged . AIM: To assess the main epidemiological characteristics of the Salmonella enteritidis epidemic in Chile . MATERIALS AND METHODS: Cases of clinical infections by Salmonella enteritidis were recorded from bacteriological and demographic notifications obtained at The National Reference Laboratory for Enterobacteria . Infection rates were calculated using the total Chilean population and the population of the different Health Services along the country . RESULTS: Until 1993, 13.67 Salmonella enteritidis strains per year were received at the Reference Laboratory . The figures increased to 478 and 432 in 1994 and 1995, respectively . National rates were 3.41 and 3.04 notifications/100,000 inhabitants in 1994 and 1995 respectively . Northern regions were the most affected and 90% of observed cases during 1994 came from Arica and Antofagasta . At the present time, 20% of cases are observed in Santiago, located in the mid-portion of the country . The outbreak has mainly affected children and young adults (70% of cases) . Strains have been isolated from stool cultures, suggesting gastrointestinal infections as the main clinical presentation . More than 98% of strains are susceptible to chloramphenicol, ampicillin, tetracycline, sulfa-trimetroprim, cefotaxime or ciprofloxacin . CONCLUSIONS: The obtained data clearly indicate the existence of an epidemic outbreak of Salmonella enteritidis infections, with a geographic progression from North to South.

Diabetes Metab, 1997 Dec, 23(6), 537 - 40
Minimisation of microbial contamination for potential islet xenografts using specific pathogen-free pigs and a protected environment during tissue preparation; Gouin E et al.; One major risk of islet xenotransplantation is transmission of infections . We thus compared microbial contamination during preparation of islets from 4 pigs conventionally breeded and slaughtered or 8 specific pathogen free (SPF) pigs, and different environmental conditions during pancreas excision . Pancreas harvested in a slaughterhouse (for conventional pigs) or in a protected autopsy room (for SPF pigs) were soaked in betadine solution and submitted to enzymatic digestion with collagenase . Islets were purified on histopaque gradient with a COBE 2991 processor . For each step of the process, a 10 ml aliquot was harvested and microbial contamination was analysed . For all animals, contamination of livers, which were not soaked in betadine solution, was also examined . Analysis of livers from the 4 conventional pigs showed polymicrobial contaminations (1,122 +/- 841 CFU/mg) with several species of Staphylococcus, Streptococcus, Bacillus and Enterobacteriaceae . For these conventional pigs, soaking of pancreas in betadine solution and presence of antibiotics in all media decreased the pancreatic contamination compared to hepatic contamination, but were unable to suppress it, as transport solution and crude suspension obtained after the digestion step with collagenase showed persistent contamination (9.7 +/- 2.4 and 10.5 +/- 4 CFU/ml, respectively) . After islet purification by histopaque gradient, no medium remained contaminated . During analysis of the 8 SPF pigs, no liver exhibited contamination . Analysis of medium from each preparation step showed complete absence of contamination for 7 pancreases . Only one contamination with Staphylococcus simulans was observed for one pancreas in transport solution (6 CFU/ml), and persisted in digestion medium (16 CFU/ml) . Finally, all purified suspensions were completely sterile . In conclusion, breeding conditions of pig islet donors, and controlled environment for pancreas excision, considerably influence the risk of microbial contamination . In order to limit the risk, SPF pigs are a suitable and compulsory source of islets.

J Chemother, 1997 Dec, 9(6), 415 - 9
Periapical abscesses: causal bacteria and antibiotic sensitivity; Goumas PD et al.; The purpose of this study was to investigate the aerobic and anaerobic flora of periapical abscesses and evaluate their susceptibility to various antibiotics . In 52 patients, with a diagnosis of periapical abscesses, pus cultures were taken . Forty-two aerobes and 122 anaerobes were revealed, with 2 or more than 2 anaerobic strains isolated in 36 patients . Infections were purely aerobic in 6%, purely anaerobic in 17% and mixed in 75%, while in 2% of the specimens there was no growth of microorganisms . Among anaerobes, microorganisms from the Bacteroides group (38.5%), Peptostreptococcus spp . (24.6%), Peptococcus spp . (13.9%), and Fusobacterium spp . (4.1%), predominated in all cultures . Among aerobes the most prevalent bacteria were streptococci (47.6%) followed by staphylococci (35.6%) while Enterobacteriaceae were isolated in 4.8% of specimens . Selected susceptibility tests performed on several anaerobic species revealed that nitroimidazole derivatives, chloramphenicol and clindamycin retain their broad spectrum killing activity against anaerobes, followed by cefoxitin and moxalactam . Of the newer quinolones, ofloxacin was the most effective . It is evident that the high isolation rate of anaerobic bacteria should influence empiric therapeutic decisions.

J Chemother, 1997 Dec, 9(6), 403 - 10
Gram-negative bacilli isolated from patients in intensive care unit: prevalence and antibiotic susceptibility; Eltahawy AT; The surveillance of 100 gram-negative bacilli that were recovered from patients in the intensive care unit (ICU) at King Abdulaziz University Hospital (KAUH), Jeddah, Saudi Arabia showed that Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Enterobacter species, in this order, were the most frequently isolated organisms . The most common sites were respiratory tract (34%), wounds (24%), urinary tract (18%), and blood (11%) . The resistance patterns towards different antimicrobial agents were determined by the minimal inhibitory concentration (MIC) using the E test . Imipenem, ciprofloxacin and amikacin were the most active agents against the isolates . Of the gram-negative isolates, 31% were resistant to at least two of the four major antibiotic groups (e.g . aminoglycosides, fluoroquinolones, third generation cephalosporins, and carbapenems), and 6% to three of the groups . Twenty-nine percent of the gram-negative bacilli were resistant to ceftazidime . Ceftazidime-resistant bacteria were frequently resistant to monobactams, piperacillin/tazobactam and gentamicin.

East Afr Med J, 1997 Jul, 74(7), 444 - 6
Role of plasmids in the virulence of enteric bacteria; Bebora LC; Plasmids have been shown to play an important role in the pathogenecity of most enterobacteria . Their involvement in various enterobacteria was discovered at different times and there is resemblance in the type of toxins produced by a number of enterobacteria and in the genes responsible for the production of the toxins and invasiveness . This indicates a spread of a factor from one bacterial strain to another, thus enabling the recipient to demonstrate the characteristic coded for . This factor may be the plasmid or chromosomal portion that codes for the characteristic.

Diagn Microbiol Infect Dis, 1998 Jan, 30(1), 45 - 52
Multicenter evaluation of the antimicrobial activity for six broad-spectrum beta-lactams in Venezuela using the Etest method . The Venezuelan Antimicrobial Resistance Study Group; Pfaller MA et al.; In early 1997, a 15-laboratory surveillance project was initiated in Venezuela to monitor the potency and spectrum of 6 broad-spectrum antimicrobial agents (cefepime, cefotaxime, ceftazidime, piperacillin, piperacillin/tazobactam, and imipenem) tested against approximately 100 organisms per participant center (1297 strains) . Ten groups of organisms were tested by the Etest method (AB BIODISK, Solna, Sweden) with results validated by concurrent quality control strain analysis . Results from all centers were tabulated and 96.3% of quality assurance tests were within ranges recommended by the National Committee for Clinical Laboratory Standards . Among the six beta-lactam class drugs tested, imipenem and cefepime were the most active against all isolates tested . Overall, the rank order of susceptibility of the six agents was imipenem (97.2%, susceptible; MIC90 2 micrograms/ml) > cefepime (92.8%; MIC90 6 micrograms/mL) > piperacillin/tazobactam (77.2-83.0%; MIC90 > 256 micrograms/mL) > cefotaxime (72.2%; MIC90 > 256 micrograms/mL) > piperacillin (56.8-65.8%; MIC90 > 256 micrograms/mL) > ceftazidime (64.66%; MIC90 128 micrograms/mL) . Both cefepime and imipenem were active against ceftazidime-resistant strains of Enterobactericaeae as well as against Pseudomonas aeruginosa and oxacillin-susceptible staphylococci . Resistance phenotypes consistent with extended spectrum beta-lactamases (ESBLs) and stably derepressed Bush group 1 cephalosporinases were documented in strains of Klebsiella spp . and Enterobacters, respectively . These data should be used to guide empiric therapy with beta-lactams in Venezuela, and additionally will provide a reference statistical baseline to which future studies in this nation can be compared.

J Biotechnol, 1997 Dec 17, 59(1-2), 117 - 26
Bioenergetic consequences of microbial adaptation to low-nutrient environments; Teixeira de Mattos MJ et al.; A striking property of many prokaryotes is their enormous metabolic flexibility with respect not only to catabolic and anabolic substrates but also with respect to the continuously changing availability of nutrients . The phenotypic responses to low-nutrient growth conditions involve structural changes in the cellular make-up, changes in the specific capacity of the enzyme system(s) involved in uptake and/or assimilation of the limiting nutrient and changes in the affinity of these enzymes . Here the responses of some members of the Enterobacteriaceae to potassium-, ammonium- and energy source-limited conditions will be reviewed . The focus will be on the energetic consequences of these adaptations as reflected by the growth yield value for the energy source (Y energy source) . It will be illustrated that Y energy source values can be dramatically lowered as a result of incomplete oxidation of the energy source (overflow metabolism), bypassing potential sites of energy conservation (uncoupling) or catabolic cycles that have no other apparent effect than the hydrolysis of ATP (futile cycles) . Thus, it is concluded that adaptation to low nutrient conditions aims at maintaining high metabolic fluxes at low nutrient concentrations at the cost of a loss in the energetic efficiency of the overall metabolism.

Ann Rheum Dis, 1997 Jul, 56(7), 421 - 5
Enhanced jejunal production of antibodies to Klebsiella and other Enterobacteria in patients with ankylosing spondylitis and rheumatoid arthritis; Maki-Ikola O et al.; OBJECTIVE: To measure gut immunity directly in jejunal fluid in patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA) . METHODS: Antibodies against three different Enterobacterias were measured in jejunal perfusion fluids (collected by a double balloon perfusion device) of 19 patients with AS, 14 patients with RA, and 22 healthy controls using enzyme linked immunosorbent assay . RESULTS: The AS patients had significantly increased jejunal fluid concentrations of IgM, IgG, and IgA class antibodies against Klebsiella pneumoniae, and IgM and IgA class antibodies against Escherichia coli and Proteus mirabilis compared with healthy controls . When compared with the patients with RA, the AS patients had higher concentrations of IgA and IgG class antibodies only against K pneumoniae . The RA patients had higher IgM class antibody concentrations against all three studied Enterobacterias, when compared with the healthy controls, suggesting an enhanced mucosal immune response in these patients . A three month treatment with sulphasalazine did not decrease enterobacterial antibody concentrations in the 10 patients with AS . CONCLUSION: There is strong direct evidence for an abnormal mucosal humoral immune response particularly to K pneumoniae in patients with AS.

J Formos Med Assoc, 1998 Jan, 97(1), 73 - 5
Course and management of renal subcapsular abscess in a 63-year-old diabetic woman; Yu WL et al.; Renal subcapsular abscess is a very rare disease that is defined by a suppurative process localized to a space between the renal capsule and the renal parenchyma . The course and management of subcapsular abscesses have received less attention than those of renal and perirenal abscesses . We describe a 63-year-old diabetic woman who presented with intermittent fever of 1 month's duration . She was initially treated for suspected acute pyelonephritis then referred to our hospital because of poor clinical response to cefazolin plus gentamicin . Computed tomography of the abdomen revealed a huge subcapsular abscess with displacement and compression of the left renal parenchyma . A percutaneous catheter was inserted and left in place for 8 days; a total of approximately 850 mL of pus was drained . Culture of the pus yielded Klebsiella pneumoniae and Enterobacter cloacae . A 2-week course of moxalactam was administered on the basis of the results of in vitro antibiotic susceptibility testing . The distorted renal parenchyma appeared normal at sonographic follow-up examination 3 weeks after hospitalization . The course and management of this rare entity are presented as a reminder to physicians that renal subcapsular abscess could manifest as fever of unknown origin in a diabetic patient . A high degree of clinical suspicion is required for early diagnosis and treatment in order to achieve a satisfactory outcome.

Mikrobiol Z, 1997 Sep-Oct, 59(5), 34 - 41
{New data on the etiological factors in acute pyelonephritis}; Rudenko AV et al.; Spectrum of microbe agents of acute pyelonephritis has been studied . It is shown that Mycoplasma hominis plays an important role in etiology of acute pyelonephritis besides the already known enterobacteria and Gram-positive cocci . It is also established that mycoplasmal pyelonephritis more often develops in patients with the diseases of urinary blade (cystitis) and genital organs . Results of serological investigations which confirm etiological role of isolated microorganisms in the initiation of acute pyelonephritis are presented.

J Biol Chem, 1998 Jan 30, 273(5), 2747 - 57
The structures of the lipopolysaccharides from Rhizobium etli strains CE358 and CE359 . The complete structure of the core region of R . etli lipopolysaccharides; Forsberg LS et al.; The structural arrangement of oligosaccharides comprising the core region of Rhizobium etli CE3 lipopolysaccharide (LPS) has been elucidated through the characterization of the LPSs from two R . etli mutants . One mutant, CE358, completely lacks the O-chain polysaccharide, while the second mutant, CE359, contains a truncated portion of this polysaccharide . This structural arrangement of the core oligosaccharides in these LPSs was determined using electrospray ionization mass spectrometry, tandem mass spectrometry, and methylation analysis . Mild acid hydrolysis of the CE359 LPS produces two major core oligosaccharides: a tetrasaccharide (1) with the structure alpha-D-Galp-(1-->6)-{alpha-D-GalpA-(1-->4)}-alpha-D-Manp-(1 -->5)-Kdo p (where Kdo represents 3-deoxy-D-manno-2-octulosonic acid) and a trisaccharide (2) having the structure alpha-D-GalpA-(1-->4)-{alpha-D-GalpA-(1-->5)}-Kdop . Structure 1 in CE358 LPS lacks the galacturonosyl residue . Glycosyl linkage and tandem mass spectrometry analyses show that the intact LPS core region consists of trisaccharide (2) attached to O-4 of the Kdo residue in tetrasaccharide 1, and that an additional Kdo residue is attached to O-6 of the galactosyl residue of 1 . {structure: see text} The additional terminally linked Kdo residue is not in close proximity to the lipid A moiety, a unique location for a core Kdo residue . The mutant LPS preparations also contain minor LPS species, one of which lacks the Kdo linked to O-6 of the galactosyl residue, another that lacks the galacturonic acid attached to O-5 of Kdo, and a third that lacks two galacturonosyl residues and one Kdo residue . Thus, in addition to lacking both heptose and phosphate, the R . etli LPS core region differs substantially from the typical enterobacterial cores . The abundance of galacturonosyl residues in the R . etli core might serve as a suitable functional replacement for phosphate, such as would be predicted for Ca2+ binding.

Indian J Exp Biol, 1997 Aug, 35(8), 912 - 4
Reductive and hydrolytic activities of enteric bacteria on food colours; Singh S et al.; Reductive and hydrolytic activities on two food colours namely metanil yellow and indigo carmine by different strains of enteric bacteria were evaluated . Enteric bacteria possessed both reductive and hydrolytic capabilities which depended upon the incubation period and the type of strain . In certain bacterial strains, (Escherichia coli and Vibrio sp.), reductive activity was visible after 3 hr . Other enteric strains showed an increasing activity right from the beginning of incubation . Enterobacter cloacae appeared to be producing maximum reductive capability followed by Enterobacter aerogenes and E . coli . Even enteric bacterial strains demonstrated a good response in obtaining hydrolytic activity of indigo carmine during incubation upto 10 hr, establishing the fact that the gut microflora may cause health problem to consumers.

J Bacteriol, 1998 Feb, 180(4), 909 - 13
A major outer membrane protein of Rahnella aquatilis functions as a porin and root adhesin; Achouak W et al.; A 38-kDa major outer membrane protein (OMP) was isolated from the nitrogen-fixing enterobacterium Rahnella aquatilis CF3 . This protein exists as a stable trimer in the presence of 2% sodium dodecyl sulfate at temperatures below 60 degrees C . Single channel experiments showed that this major OMP of R . aquatilis CF3 is able to form pores in the planar lipid membrane . Two oligonucleotides encoding the N-terminal portion of the 38-kDa OMP and C-terminal portion of OmpC were used to amplify the 38-kDa gene by PCR . The deduced amino acid sequence showed a strong homology with Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, and Serratia marcescens OmpC sequences, except loops L6 and L7, which are postulated to be cell surface exposed . On the basis of the OmpF-PhoE three-dimensional structure, it seems likely that this 38-kDa organizes three 16-strand beta-barrel subunits . The relationship between the structure and the double functionality of this protein as porin and as a root adhesin is discussed.

Wien Med Wochenschr, 1997, 147(19-20), 465 - 9
{Pathogenetic aspects of urinary tract infection}; Funfstuck R et al.; Most urinary tract infections are caused by Enterobacteriaceae; E . coli-strains dominating in 50 to 80% of primary infections . Microorganisms possessing the ability to colonize the uroepithelium (fimbriae/pili) and to cytotoxically damage of cells (hemolysin) may initiate acute infections . On the other hand, properties favouring the survival of these strains in the tissue (K-antigen, iron sequestering/aerobactin) tend to produce relapse and/or chronic infection . A variety of host-specific factors, especially glycosphingolipids, on the surface of epithelial cells determine the virulence of pathogenic microorganisms in the urinary tract and the course of a disease . Structural damages resulting from intra- or extrarenal obstructions, disturbances of the urinary flow and metabolic disorders are essential, predisposing factors of a host organism . These different factors and interactions of these mechanisms determine the manifestation and course of urinary tract infections.

Intensive Care Med, 1997 Dec, 23(12), 1251 - 7
Endogenous endotoxemia of intestinal origin during cardiopulmonary bypass . Role of type of flow and protective effect of selective digestive decontamination; Martinez-Pellus AE et al.; OBJECTIVE: To evaluate the possible related factors to endotoxemia and cytokine activation during the ischemic phase of extracorporeal surgery, and the effect of selective digestive decontamination (SDD) as a preventive measure . DESIGN: Prospective, open, randomized trial . SETTING: Two multidisciplinary ICUs (tertiary care hospitals) . PATIENTS: One hundred consecutive patients undergoing cardiopulmonary bypass (CPB), randomly allocated to two groups; gut decontamination (group I = 50 cases) and controls (group II = 50 cases) . INTERVENTIONS: Preoperative administration of oral non-absorbable antibiotics (polymyxin E, tobramycin and amphotericin B) versus no administration . MEASUREMENTS AND RESULTS: The assessment of decontamination by means of the bacteriologic control of rectal swabs . Determinations of gastric intramucosal pH (gastric pHi) and plasma endotoxin, tumor necrosis factor (TNF) aNd interleukin-6 (IL-6) before surgery and during the ischemic and reperfusion phases of bypass . Rectal aerobic Gram-negative bacilli (AGNB) were significantly reduced in the treated patients and in 56% total eradication was achieved . Endotoxin, TNF and IL-6 plasma levels were significantly lower in this group . By contrast, both endotoxin and TNF/IL-6 levels and gastric pHi correlated with the type of surgical flow (pulsatile versus non-pulsatile) . CONCLUSIONS: SDD reduces the gut content of enterobacteria . This may explain the lower endotoxin and cytokine levels detected in decontaminated patients . In addition to SDD, the type of flow employed during bypass seems to influence endotoxemia and cytokine levels.

Am J Gastroenterol, 1998 Feb, 93(2), 234 - 7
Liver damage in human small intestinal bacterial overgrowth; Riordan SM et al.; OBJECTIVE: Some rodent strains with experimental small intestinal bacterial overgrowth (SIBO) unrelated to jejunoileal bypass are susceptible to hepatic damage, possibly because of increased small intestinal permeability to proinflammatory bacterial polymers . However, data on the prevalence of hepatic damage in human subjects with SIBO in this setting are lacking . This study addressed this issue . METHODS: Seventy adult subjects were investigated for possible SIBO and hepatic damage with bacteriological analysis of small intestinal aspirates and measurement of serum concentrations of alkaline phosphatase, gamma-glutamyl transpeptidase, aspartate aminotransferase, and alanine aminotransferase . Nutritional indices (serum albumin and anthropometry) and the urinary lactulose/mannitol ratio, an index of small intestinal permeability, were measured in all subjects with SIBO and liver damage . RESULTS: SIBO was present in 40 of 70 subjects (57.1%) . Overgrowth flora included salivary-type bacteria alone in 11 subjects and colonic-type bacteria in 29 subjects (facultative anaerobes {Enterobacteriaceae} alone in 21 subjects and both facultative and obligate anaerobes {Enterobacteriaceae and Bacteroides spp} in eight subjects) . Biochemical evidence of liver damage was found in zero of 30 subjects without SIBO, zero of 11 subjects with SIBO with salivary-type bacteria alone, zero of 21 subjects with SIBO with facultative but not obligate anaerobic colonic-type bacteria, and in one of eight subjects (12.5%) with SIBO with obligate anaerobic colonic-type bacteria, in whom serum alkaline phosphatase and gamma-glutamyl transpeptidase levels were elevated . Nutritional indices were normal in this patient . Small intestinal permeability was increased and, along with liver enzyme abnormalities, normalized after eradication of SIBO . Small intestinal permeability was also increased in three of six patients (50.0%) with SIBO with obligate anaerobic colonic-type bacteria who had no evidence of liver damage . CONCLUSIONS: SIBO per se is not a major risk factor for liver damage in humans, even when the overgrowth flora includes obligate anaerobes . Liver damage is not a necessary consequence of increased small intestinal permeability in this setting.

Microbios, 1997, 91(367), 97 - 103
Susceptibilities of 97 strains of Xanthomonas maltophilia to antibiotics and the effect of beta-lactamase inhibitors; Ismaeel NA; An agar dilution technique and the 'E' test were used to compare the antimicrobial activities of ticarcillin, ticarcillin-clavulanate, ampicillin, ampicillin-sulbactam, piperacillin, piperacillin-tazobactam, meropenem, biapenem, imipenem, levofloxacin, ofloxacin, ciprofloxacin, ceftazidime and cefepime against 97 clinical isolates of Xanthomonas maltophilia . Intermediate susceptibility breakpoints for members of the family Enterobacteriaceae were used . Results were analysed as minimum inhibitory concentrations for 50 and 90% of the strains tested and as percentages of strains susceptible at the breakpoint . Good correlation between the two techniques was observed, with ticarcillin-clavulanate clearly the most active agent by both methods with 64 to 66% followed by levofloxacin with 63 to 65% of the strains being susceptible . Biapenem and imipenem showed weak activity with none of the strains being susceptible . Ceftazidime had better activity than cefepime when they were compared by the two methods . There was no significant difference in the results between the two susceptibility techniques used.

Oral Microbiol Immunol, 1997 Jun, 12(3), 183 - 8
A 4-year longitudinal study of the oral prevalence of enteric gram-negative rods and yeasts in Chinese children; Sedgley CM et al.; A 4-year longitudinal study of the oral prevalence of enteric gram-negative rods and yeasts in 116 Chinese primary school children in Hong Kong was conducted . The oral prevalence of enteric gram-negative rods for each consecutive year was 25.3%, 37.0%, 24.0% and 25.8% respectively, with a weighted mean of 27.9% . Enterobacteriaceae, which comprised 57% of all enteric gram-negative rods, were more common in children with no caries experience . The oral prevalence of yeasts for each consecutive year was 7.7%, 12.0%, 14.4% and 15.5% respectively, with a weighted mean of 12.5% . Candida albicans comprised 84% of all yeasts isolated . Oral yeast carriage was significantly associated with caries prevalence . While the oral prevalence of enteric gram-negative rods in primary school children in Hong Kong may be higher than in other parts of the world, repeated isolation of either enteric gram-negative rods or Candida spp . from individual children over the 4-year study period was rare, suggesting that carriage of these organisms is transient.

Zentralbl Veterinarmed B, 1997 Dec, 44(10), 577 - 82
Clinical disorders in armadillos (Dasypodidae, Edentata) in captivity; Diniz LS et al.; The major health problems found in 113 armadillos are presented and correlated with management in captivity . The most common of 217 recorded clinical disorders involved injury (28.5%), digestive system (17.9%), respiratory system (15.2%), nutritional deficiency (13.3%), skin problems (3.6%), septicaemia (1.8%), nervous system (1.3%), urinary system (0.9%) and effects of environmental (0.9%), with 14.7% of the cases inconclusive . Internal parasites were identified in 42.0% of faeces samples, mainly eggs of helminths (66.6%), of which the commonest were Ancylostoma sp . (33.3%), Strongyloides sp . (30.5%), Ascaris sp . (25.0%), Trichuris sp . (11.1%), and also protozoa (13.0%) . Enterobacteriaceae were the bacteria most frequently isolated, with Escherichia coli the most prevalent, followed by Salmonella sp . and Enterobacter aerogenes . The most successful treatments are listed . The influence of some captive factors on the onset of the diseases was also analysed: donated animals 91.1% and zoo born 8.8%; quarantine enclosure 84.0% and exhibition 15.0%; and related to time in captivity, 92.2% occurred with animals in the first 6 months in the zoo and 7.8% with animals more than 6 months.

Appl Environ Microbiol, 1998 Feb, 64(2), 651 - 8
Identification of bacterial isolates obtained from intestinal contents associated with 12,000-year-old mastodon remains; Rhodes AN et al.; Mastodon (Mammut americanum) remains unearthed during excavation of ancient sediments usually consist only of skeletal material, due to postmortem decomposition of soft tissues by microorganisms . Two recent excavations of skeletal remains in anoxic sediments in Ohio and Michigan, however, have uncovered organic masses which appear to be remnants of the small and large intestines, respectively . Macrobotanical examinations of the composition of these masses revealed assemblages of plant material radiocarbon dated to approximately 11,500 years before the present and thought to be incompletely digested food remains from this extinct mammal . We attempted to cultivate and identify bacteria from the intestinal contents, bone-associated sediments, and sediments not in proximity to the remains using a variety of general and selective media . In all, 295 isolates were cultivated, and 38 individual taxa were identified by fatty acid-methyl ester (FAME) profiles and biochemical characteristics (API-20E) . The taxonomic positions of selected enteric and obligately anaerobic bacteria were confirmed by 16S ribosomal DNA (rDNA) sequencing . Results indicate that the intestinal and bone-associated samples contained the greatest diversity of bacterial taxa and that members of the family Enterobacteriaceae represented 41% of all isolates and were predominant in the intestinal masses and sediments in proximity to the skeleton but were uncommon in the background sediments . Enterobacter cloacae was the most commonly identified isolate, and partial rDNA sequencing revealed that Rahnella aquatilis was the correct identity of strains suggested by FAME profiles to be Yersinia enterocolitica . No Bacteroides spp . or expected intestinal anaerobes were recovered . The only obligate anaerobes recovered were clostridia, and these were not recovered from the small intestinal masses . Microbiological evidence from this study supports other, macrobotanical data indicating the intestinal origin of these masses . Whether these organisms are direct descendants of the original intestinal microbiota, however, cannot be established.

J Antimicrob Chemother, 1997 Dec, 40(6), 863 - 71
Sequential therapy with cefuroxime followed by cefuroxime axetil in acute exacerbations of chronic bronchitis; Vogel F et al.; A prospective, multicentre, randomized, open-label, parallel group study compared the efficacy, safety and tolerability of cefuroxime 750 mg iv administered either twice daily (bd) or three times daily (tds) for 48-72 h, followed by oral cefuroxime axetil 500 mg bd for 5-7 days in a sequential therapy regimen for the treatment of acute exacerbations of chronic bronchitis . A total of 628 adult patients entered the study; 323 in the cefuroxime tds group and 305 in the cefuroxime bd group . For clinically evaluable patients, the post-treatment clinical response rate was 86% and 88% in the cefuroxime tds and bd groups, respectively . Cure was maintained at follow-up (14-28 days after treatment completion) in 85% of the cefuroxime tds group and 84% of patients in the cefuroxime bd group . A total of 189 pathogens was isolated, the most common being Haemophilus influenzae (17%), other Haemophilus spp . (15%), Streptococcus pneumoniae (15%) and Enterobacteriaceae (23%) . At the post-treatment assessment, 66% and 70% of pathogens were cleared in the cefuroxime tds and bd groups, respectively . Both treatment regimens were well tolerated . The incidence of drug-related adverse events was 7% in the cefuroxime tds group and 6% in the cefuroxime bd group; the most common side-effects were gastrointestinal . Qualitative and quantitative markers were used to determine the optimal time to switch from iv to oral therapy and, of these, peak expiratory flow rate was shown to be the most useful in the present study . In conclusion, the findings of this study support the use of a bd dosing schedule of cefuroxime in a sequential therapy regimen with oral cefuroxime axetil, demonstrating it to be clinically equivalent to the standard tds dosage currently used, as well as being simpler and more convenient to administer at a lower cost.

Urol Nefrol (Mosk), 1997 Nov-Dec, (6), 7 - 14
{Current aspects in the diagnosis and treatment of chronic cystitis in women}; Loran OB et al.; Chronic cystitis (CC) in females is annually encountered now in 15,000-20,000 per 1,000,000 . Etiological and pathogenetic factors in CC are closely related . Bacteriologically, CC is represented primarily by Enterobacter . The infection, as a rule, ascends the lower urinary tracts . The contributing factors are: weak local antibacterial mechanisms of the urogenital system, anatomical variants and anomalies of the urethra and introitus, sexual activity, impaired urodynamics of the lower urinary tracts . The diagnosis of chronic inflammation of the bladder is made mainly endoscopically, with obligatory endovesical multifocal biopsy of the bladder followed by histological examination . The treatment of CC includes antibacterial, general and local antiinflammatory therapy, measures to normalize urodynamics of the lower urinary tracts, correction of hygienic and sexual factors, immunostimulation . 16 nonresponders to conservative treatment of interstitial cystitis with progressive contraction of the bladder were subjected to supratrigonal or subtotal resection of the bladder with one-stage ileocystoplasty.

J Clin Microbiol, 1998 Jan, 36(1), 248 - 50
First report of a human isolate of Erwinia persicinus; O'Hara CM et al.; Erwinia persicinus was first described in 1990 after being isolated from a variety of fruits and vegetables, including bananas, cucumbers, and tomatoes . In 1994, it was shown to be the causative agent of necrosis of bean pods . We now report the first human isolate of E . persicinus . The strain was isolated from the urine of an 88-year-old woman who presented with a urinary tract infection . By the hydroxyapatite method, DNA from this strain was shown to be 94.5% related at 60 degrees C and 86% related at 75 degrees C to the type strain of E . persicinus . The biochemical profile of E . persicinus is most similar to those of Erwinia rhapontici, Pantoea agglomerans, and Enterobacter species . It is negative in tests for lysine, arginine, ornithine, dulcitol, and urea . It is motile and positive in tests for D-sorbitol and sucrose . It is susceptible to the expanded-spectrum cephalosporins, aminoglycosides, and fluoroquinolones, but it is resistant to ampicillin, ticarcillin, and cefazolin.

J Clin Microbiol, 1998 Jan, 36(1), 128 - 32
Enterobacterial repetitive intergenic consensus sequences as molecular targets for typing of Mycobacterium tuberculosis strains; Sechi LA et al.; The presence of enterobacterial repetitive intergenic consensus (ERIC) sequences was demonstrated for the first time in the genome of Mycobacterium tuberculosis; these sequences have been found in transcribed regions of the chromosomes of gram-negative bacteria . In this study genetic diversity among clinical isolates of M . tuberculosis was determined by PCR with ERIC primers (ERIC-PCR) . The study isolates comprised 71 clinical isolates collected from Sardinia, Italy . ERIC-PCR was able to identify 59 distinct profiles . The results obtained were compared with IS6110 and PCR-GTG fingerprinting . We found that the level of differentiation obtained by ERIC-PCR is greater than that obtained by IS6110 fingerprinting and comparable to that obtained by PCR-GTG . This method of fingerprinting is rapid and sensitive and can be applied to the study of the epidemiology of M . tuberculosis infections, especially when IS6110 fingerprinting is not of any help.

J Clin Microbiol, 1998 Jan, 36(1), 48 - 51
Enterobacter cloacae endophthalmitis: report of four cases; Okhravi N et al.; Members of the genus Enterobacter are commensal organisms of the gastrointestinal tract and are considered pathogenic only for patients with lowered resistance to infection (e.g., chronic infection, cancer, or diabetes mellitus) or those with impaired immunity (congenital, acquired, or impaired immunity secondary to therapy) . We report on four cases of endophthalmitis caused by Enterobacter cloacae: two in patients with acute postoperative endophthalmitis, one in a patient with delayed bleb-related endophthalmitis, and one in a patient presenting with presumed posttraumatic endophthalmitis . Each patient presented with severe disease many days after the onset of ocular symptoms, and two patients had systemic risk factors accounting for a reduced resistance to infection . Endophthalmitis caused by gram-negative bacilli is characterized by acute onset, rapid progression, and poor final visual outcome . Each of these patients was treated by a standard protocol with intravitreal, systemic, and topical antibiotics and systemic steroids . Despite treatment, the final visual outcomes for three of these patients was no perception of light, and that for one patient remained perception of hand movements only . In common with endophthalmitis caused by other gram-negative organisms, intraocular infection secondary to Enterobacter cloacae infection is a devastating disease which, despite treatment, results in extensive ocular damage and severe visual loss . Since 1966, only four cases of endophthalmitis secondary to infection with members of this genus have been reported . This report presents four cases which occurred over a period of 14 months and, to the best of our knowledge, the first case of bleb-related endophthalmitis secondary to E . cloacae infection.

J Med Assoc Thai, 1997 Nov, 80(11), 742 - 5
Cefaclor therapy in uncomplicated cystitis; Asvanich K et al.; Thirty patients with acute urinary tract infection were treated orally with 500 mg of cefaclor three times a day for 7 days . Urine cultures were made before treatment and after therapy . In 97 per cent (29/30) of these patients clinical success was achieved and in 90 per cent (27/30) of them, pathogens were eradicated . Our study showed that cefaclor was still active against most Enterobacteriaceae, such as Escherichia coli and Klebsiella species, the principle pathogens of urinary tract infection . No adverse effects of cefaclor were observed in this study.

Boll Chim Farm, 1997 Jun, 136(6), 483 - 7
{Experimental-practical study of some methods for culturing and counting enterobacteria from raw materials and oral medical preparations}; Casetta P et al.; The technique of enterobacteria enumeration according to F.U., by rivivification in Lactose Broth for 5 h at 37 degrees C and subsequent incubation in Enterobacteriaceae Enrichment Broth, causes artful increases of the number of enterobacteria, often resulting higher than the total microbial charge . To eliminate the drawback we have assayed other two methods: a) incubation in Soybean Casein Digest Broth for 5 h at 37 degrees C, followed by enumeration onto Violet Red Bile Dextrose Agar plates; b) incubation into Soybean Casein Digest Agar plates for 5 h at 37 degrees C, followed by enumeration onto overlayed Violet Red Bile Dextrose Agar . The experimental investigations were performed on 8 artificially stressed (heating, freezing) strain of Enterobacteriaceae and carried out the superiority of the method onto Soybean Casein Digest Agar + Violet Red Bile Dextrose Agar plates . This method was tested on No . 302 samples of raw materials and pharmaceutical preparations, that shown an enterobacterial charge higher than 100 C.F.U . in 24 cases (8%) . On the contrary, the enumeration of the enterobacteria according to the F.U . method (Lactose Broth + Enterobacteriaceae Enrichment Broth + Violet Red Bile Dextrose Agar) carried out an enterobacterial charge higher than 100 C.F.U . in 270 cases (89.4%) . Indeed, the artful increase of the number of enterobacteria may make unacceptable pharmaceutical preparations suitable for the market . The employment of the method of enumeration of the enterobacteria onto Soybean Casein Digest Agar + Violet Red Bile Dextrose Agar plates is augured.

Kaohsiung J Med Sci, 1997 Sep, 13(9), 525 - 33
Genetic localization of the type I trimethoprim resistance gene and its dissemination in urinary tract isolates in Taiwan; Chang LL et al.; In a total of 425 urinary isolates of E . coli, Enterobacter spp., and Klebsiella spp . selected, there were 169 (45.4%) isolates harbouring type I dihydrofolate reductase (DHFR) gene among 374 trimethoprim-resistant isolates . In these 169 isolates, only 17.2% hybridized with the Tn7 probe . According to another probe specific for the integrase gene of integron, 87.6% showed a positive reaction . Further analysis by restriction mapping proved that the type I DHFR gene was inserted into a integron-like structure . These results indicate that the type I DHFR gene that was initially observed in association with transposable element Tn7 is becoming associated with an integrase function similar to integrons in most instances . Further analysis of the distribution of Tn21-like integrase gene in clinical isolates indicated that the prevalence rates were 86.4%, 84.8%, and 76.7% respectively in E . coli, Enterobacter spp., and Klebsiella spp. . Furthermore, the integrase gene found in our clinical isolates proved to be mediated by a plasmid, demonstrated by Southern hybridization . Thus, the trimethoprim-resistant gene that developed under selective pressure from the double drug trimethoprim and sulphonamide was transmitted by insertion into integron-like structure and then mediated by plasmid transfer for dissemination.

Infect Immun, 1998 Feb, 66(2), 645 - 9
Occurrence of virulence-associated properties in Enterobacter cloacae; Keller R et al.; Enterobacter cloacae is not a primary human pathogen but has been considered to be an important cause of nosocomial infections . Even so, there are almost no reports on its ability to produce recognized virulence-associated properties . In this study, we show that most of the E . cloacae strains examined were resistant to serum bactericidal activity and were able to produce aerobactin and mannose-sensitive hemagglutinin, and all of them could adhere to and invade HEp-2 cells . Since E . cloacae is part of the normal intestinal floras of many individuals, we believe that infectious disease due to endogenous E . cloacae might be a result of both host predisposing factors and the bacterial virulence determinants that we have detected in this survey.

Infect Immun, 1998 Feb, 66(2), 480 - 5
Prevalence of the "high-pathogenicity island" of Yersinia species among Escherichia coli strains that are pathogenic to humans; Schubert S et al.; The fyuA-irp gene cluster contributes to the virulence of highly pathogenic Yersinia (Yersinia pestis, Yersinia pseudotuberculosis, and Yersinia enterocolitica 1B) . The cluster encodes an iron uptake system mediated by the siderophore yersiniabactin and reveals features of a pathogenicity island . Two evolutionary lineages of this "high pathogenicity island" (HPI) can be distinguished on the basis of DNA sequence comparison: a Y . pestis group and a Y . enterocolitica group . In this study we demonstrate that the HPI of the Y . pestis evolutionary group is disseminated among species of the family Enterobacteriaceae which are pathogenic to humans . It prevails in enteroaggregative Escherichia coli and in E . coli blood culture isolates (93 and 80%, respectively), but is rarely found in enteropathogenic E . coli, enteroinvasive E . coli, and enterotoxigenic E . coli isolates . In contrast, the HPI was absent from enterohemorrhagic E . coli, Shigella, and Salmonella enterica strains investigated . Polypeptides encoded by the fyuA, irp1, and irp2 genes located on the HPI could be detected in E . coli strains pathogenic to humans . However, these E . coli strains showed a reduced sensitivity to the bacteriocin pesticin, whose uptake is mediated by the FyuA receptor . Escherichia strains do not possess the hms gene locus thought to be a part of the HPI of Y . pestis . Deletions of the juA-irp gene cluster affecting solely the fyuA part of the HPI were identified in 3% of the E . coli strains tested . These results suggest horizontal transfer of the HPI between Y . pestis and some pathogenic E . coli strains.

FEMS Microbiol Lett, 1998 Jan 1, 158(1), 115 - 20
Immuno-detection of the virulence determinant OmpX at the cell surface of Enterobacter cloacae; de Kort G et al.; A model for the topology of the Enterobacter cloacae outer membrane protein OmpX has been proposed, based on the primary sequence and on analogy to homologous proteins . According to this model the membrane embedded part of the protein consists of eight antiparallel beta-strands . Four random coil loops are located at the bacterial surface and three beta-turns at the periplasmic side of the membrane . Antibodies were raised against synthetic peptides representing five OmpX domains, four of which are putative peripheral and one located in the membrane . The accessibilities of OmpX to these antibodies were tested in intact cells by immuno-gold electron microscopy . This study showed that OmpX is indeed an outer membrane protein, the N-proximal loop of which forms an IgG-accessible epitope at the cell surface.

World J Surg, 1998 Feb, 22(2), 158 - 63
Tertiary peritonitis: clinical features of a complex nosocomial infection; Nathens AB et al.; The objective of this study was to define risk factors for and the clinical course of recurrent or tertiary peritonitis . Intensive supportive care of patients with life-threatening intraabdominal infections has led to the emergence of a new clinical syndrome, tertiary peritonitis, defined as the persistence or recurrence of intraabdominal infection following apparently adequate therapy of primary or secondary peritonitis . We undertook a retrospective study of 59 patients admitted with intraabdominal infection to a surgical intensive care unit (ICU) . Tertiary peritonitis developed in 74% (44/59) of patients . Despite comparable premorbid health status, source of peritonitis, and admission APACHE II scores, patients with tertiary peritonitis had a significantly longer ICU stay (21.8 +/- 14.9 vs . 8.5 +/- 7.9 days), more advanced organ dysfunction reflected in higher organ dysfunction scores (13.3 +/- 5.1 vs . 7.7 +/- 3.3), and higher ICU mortality (64% vs . 33%) than patients with uncomplicated secondary peritonitis . The most common infecting organisms in patients with tertiary peritonitis were Enterococcus, Candida, Staphylococcus epidermidis, and Enterobacter . Infectious foci were rarely amenable to percutaneous drainage and were found to be poorly localized at laparotomy . Recurrent, or tertiary, peritonitis is a common complication of intraabdominal infection in patients admitted to an ICU . It differs from uncomplicated secondary peritonitis in its microbial flora and lack of response to appropriate surgical and antibiotic therapy . Like nosocomial pneumonia in the critically ill patient, the syndrome appears to be more a reflection than a cause of adverse outcome.

Biometals, 1998 Jan, 11(1), 1 - 12
Selective growth promotion and growth inhibition of gram-negative and gram-positive bacteria by synthetic siderophore-beta-lactam conjugates; Mollmann U et al.; Conjugates of a carbacephalosporin with hydroxamate, spermexatol, N alpha,N epsilon-bis(2,3-dihydroxybenzoyl)-L-lysine, mixed catecholate/hydroxamate and cyanuric acid-based siderophores were investigated for their potential to promote growth of siderophore indicator strains of Gram-negative and Gram-positive bacteria under iron depleted conditions, for their antibacterial activity and for their ability to use iron transport pathways to penetrate the Gram-negative bacterial outer membrane . The selective growth promotion of enterobacterial and pseudomonas strains by hydroxamate, spermexatol and mixed catecholate-hydroxamate siderophore-based conjugates bearing a L- or D-amino acid spacer was correlated with TonB dependent uptake routes . The preferred outer membrane siderophore receptor used in Escherichia coli was found to be Fiu, followed by Cir . Antagonistic effects of siderophores administered with the conjugates to determine antibacterial activity confirmed the active transport of conjugates via siderophore receptors . All of the conjugates were still able to diffuse through the porin proteins OmpC and OmpF . Nevertheless, strong inhibition of E . coli and Pseudomones aeruginosa outer membrane mutants DC2 and K799/61 compared to the parent strains indicated inefficient penetrability of all types of conjugates tested . Mycobacterium smegmatis SG 987 was able to use all of the siderophore-cephalosporin conjugates as growth promotors . Consequently there was no growth inhibition of this strain.

Carbohydr Res, 1997 Nov 10, 304(2), 125 - 32
Some properties and action mode of (1-->4)-alpha-L-guluronan lyase from Enterobacter cloacae M-1; Shimokawa T et al.; An intracellular alginate lyase was purified from Enterobacter cloacae M-1 by successive fractionation on Q Sepharose FF, SP Sepharose FF, and Sephacryl S-200 HR . The purified enzyme gave a single band on SDS-PAGE and isoelectric focusing . The enzyme easily degraded polyguluronate and produced unsaturated oligoguluronic acids with a wide range of dp . The major end product of the enzyme reaction on polyguluronate was unsaturated triuronic acid . The pattern of oligoguluronic acids (dp 2-9) generated with the enzyme was investigated by fluorophore-assisted carbohydrate electrophoresis . The enzyme was not capable of degrading oligoguluronic acids having dp < 4 . The degradation rate of heptaguluronic acid by this enzyme remarkably increased, compared with that of hexaguluronic acid, and heptaguluronic acid had a single preferential point of cleavage by this enzyme . On the basis of the cleavage pattern of oligoguluronic acids, the number of subsites was estimated to be seven for this enzyme . The catalytic site of the enzyme is located between the second and the third subsites from the non-reducing end.

Antimicrob Agents Chemother, 1998 Jan, 42(1), 94 - 9
In vitro and in vivo antibacterial activities of S-4661, a new carbapenem; Tsuji M et al.; The in vitro and in vivo antibacterial activities of S-4661, a new 1beta-methylcarbapenem, were compared with those of imipenem, meropenem, biapenem, cefpirome, and ceftazidime . The activity of S-4661 against methicillin-susceptible staphylococci and streptococci was comparable to that of imipenem, with an MIC at which 90% of the strains tested were inhibited (MIC90) equal to 0.5 microg/ml or less . S-4661 was highly active against members of the family Enterobacteriaceae, Haemophilus influenzae, and Moraxella catarrhalis, with MIC90s ranging from 0.032 to 0.5 microg/ml . Against imipenem-resistant Pseudomonas aeruginosa, S-4661 was the most active among test agents (MIC90, 8 microg/ml) . Furthermore, S-4661 displayed a high degree of activity against many ceftazidime-, ciprofloxacin-, and gentamicin-resistant isolates of P . aeruginosa . The in vivo efficacy of S-4661 against experimentally induced infections in mice caused by gram-positive and gram-negative bacteria, including penicillin-resistant Streptococcus pneumoniae and drug-resistant P . aeruginosa, reflected its potent in vitro activity and high levels in plasma in mice . We conclude that S-4661 is a promising new carbapenem for the treatment of infections caused by gram-positive and -negative bacteria, including penicillin-resistant S . pneumoniae and drug-resistant P . aeruginosa.

J Perinatol, 1997 Nov-Dec, 17(6), 428 - 33
Bacterial and Ureaplasma colonization of the airway: radiologic findings in infants with bronchopulmonary dysplasia; Cordero L et al.; OBJECTIVE: We designed this retrospective study to compare radiologic findings in premature infants with bronchopulmonary dysplasia (BPD) in whom gram-positive cocci (GPC), gram-negative bacilli (GNB), or Ureaplasma urealyticum were colonized . Another objective was to correlate the radiologic findings of these patients with the clinical severity of BPD . STUDY DESIGN: We correlated serial tracheal aspirates with radiographic findings from 183 infants whose birth weight was < or = 1250 gm . BPD severity was assessed by oxygen dependency at 36 weeks of postconceptional age (36 w PCA) and at the time of discharge . Two radiologists independently scored films taken at birth and 1, 7, 14, 21, 28, and 35 days of life . RESULTS: Of the study population, 55% were male and 35% were black; 80% received surfactant and 69% received dexamethasone; 91% survived . GPC isolates from throat cultures were mainly Staphylococcus {corrected} epidermidis and Streptococcus haemolyticus . A superimposed GNB colonization was present in 37% of these infants . Most common isolates were Klebsiella pneumoniae, Enterobacter cloacae, and Escherichia coli . Sepsis caused by GPC developed in 16% of all patients; 7% had sepsis caused by GNB . Infants infected with GNB remained receiving oxygen at 36 w PCA and at the time of discharge twice as often as those noninfected . RADIOLOGIC FINDINGS: Hyperinflation, interstitial changes, and generalized or localized emphysema were prominent features throughout . Mean radiologic scores increased over time in a pattern similar among GPC, GNB, and U . urealyticum infected and noninfected infants . High radiologic scores were not predictive at any time of infants who needed supplemental oxygen at 28 days and at 36 w PCA . Infants infected with U . urealyticum were neither clinically nor radiologically different than noncolonized neonates . CONCLUSION: GPC, GNB, and U . urealyticum airway colonization is not associated with particular radiographic changes at any time . GNB-infected infants had the most severe BPD course, and yet they were radiologically indistinguishable from the other patients . U . urealyticum colonization does not result in more clinically severe BPD or demonstrate a unique radiologic course.

Genetika, 1997 Oct, 33(10), 1341 - 4
{Evidence of autogenic regulation of rplJ gene expression in Thermotoga maritima and possibility of autogenic cross-regulation of expression between T . maritima and enterobacteria}; Paton EB et al.; Regulatory interaction of the L10 protein and translation operator of L10 mRNA was studied in vivo using a double-plasmid system . Feedback regulation of rplJ gene expression in Thermotoga maritima was proved, and the possibility of feedback cross-regulation was demonstrated in a heterologous system containing T . maritima and enterobacterial components.

Infect Control Hosp Epidemiol, 1997 Dec, 18(12), 809 - 13
Multiply antibiotic-resistant gram-negative bacilli in a long-term-care facility: a case-control study of patient risk factors and prior antibiotic use; Muder RR et al.; OBJECTIVE: To determine the relation between prior exposure to specific antimicrobials and acquisition of gram-negative bacilli resistant to multiple beta-lactam and aminoglycoside antibiotics among long-term-care patients . DESIGN: Case-control study . Cases were patients from whom multiply resistant Enterobacteriaceae or Pseudomonas aeruginosa were isolated; controls were patients from whom nonresistant bacteria of the same species were isolated . Prospectively defined risk factors included underlying illness, activity level, presence of decubitus ulcers, presence of indwelling devices, and prior exposure to specific antimicrobial agents . Resistant and control isolates of P aeruginosa were compared using pulsed-field gel electrophoresis (PFGE) of genomic DNA after digestion with XbaI . SETTING: 390-bed long-term Veterans' Affairs facility . RESULTS: We identified 35 patients with multiply resistant Enterobacteriaceae and 24 patients with multiply resistant P aeruginosa . Of the resistant Enterobacteriaceae, 87% of isolates were resistant to piperacillin, 55% to ceftazidime, and 90% to gentamicin . Acquisition of multiply resistant Enterobacteriaceae was associated with presence of decubitus ulcers (odds ratio {OR}, 12.2; 95% confidence interval {CI95}, 3.3-44.2; P = .0002) and prior receipt of ampicillin (OR, 13.7; CI95, 2.2-84; P = .005) . Of resistant isolates of P aeruginosa, 88% were resistant to piperacillin, 25% to ceftazidime, 42% to imipenem, and 67% to ciprofloxacin . Isolation of a multiply resistant P aeruginosa was associated with total days of antimicrobial exposure (OR, 1.07; CI95, 1.01-1.12; P = .011) and not with prior receipt of any individual agent . Eleven multiply resistant isolates shared a common PFGE pattern . CONCLUSIONS: In our long-term-care facility, acquisition of multiply resistant Enterobacteriaceae was associated with the presence of decubitus ulcers and prior exposure to ampicillin . Acquisition of resistant P aeruginosa was associated with total antibiotic exposure . Molecular typing of P aeruginosa isolates implicated patient-to-patient transmission of a limited number of resistant strains.

Med Clin (Barc), 1997 Oct 11, 109(12), 452 - 6
{Chronic enteropathy of unknown etiology in patients with AIDS . An analysis of 40 cases}; Moreno Camacho A et al.; BACKGROUND: Data about the etiology of chronic enteropathy in AIDS patients are scarce and are very dependent upon the geographical area . The aim of this study was to detect microorganisms potentially associated with chronic enteropathy in AIDS patients with diarrhoea for more than one month, and initial negative routine stool bacterial cultures and examinations for ova and parasites . The degrees of associated intestinal malabsorption and immunodeficiency were also analysed . PATIENTS AND METHODS: Forty consecutive patients were recruited from January 1993 to December 1994 . The following studies were performed: Intestinal absorption tests (d-xylose and 14C-triolein), CD4/CD8 cell counts, microbiological studies (standard stool cultures for detection of bacteria and examinations for ova and parasites including the detection of Enterocitozoon bieneusi spores by the Weber's stain), upper gastrointestinal endoscopy or colonoscopy with intestinal biopsies and blood cultures for CMV and mycobacteria . RESULTS: The median duration of diarrhoea was 4 months and the mean weight loss was 8.4 kg . Ninety percent of patients had less than 0.1 x 10(9) CD4+ cells/l, with a mean CD4+ cell count of 0.035 x 10(9)/l . Malabsorption was found in 84% of patients . An etiological diagnosis of chronic enteropathy was reached in 60% of the patients . The yield of pathological examination was 37% and the microbiological test using samples of faeces and blood were positive in 45% and 20% of cases respectively . The most frequently identified microorganisms were CMV (10 cases), E . bieneusi (9), enterobacteria (8), Cryptosporidium parvum (5), Leishmania donovani (2) . Patients with enteropathy caused by E . bieneusi had lower count of CD4 cells (p = 0.005) and with higher serum levels of alkaline phosphatase (p = 0.02) than patients with CMV enteropathy . CONCLUSIONS: Stool Weber's stain and CMV and mycobacterial blood cultures should be added to the standard work-up diagnosis in patients with chronic diarrhoea and a CD4+cells count below 0.1 x 10(9) l . Upper and/or lower gastrointestinal endoscopies with intestinal biopsies should be performed only in patients with persistent diarrhea without microbiological diagnosis or a lack of response to treatment.

J Bacteriol, 1998 Jan, 180(2), 403 - 6
Staphylococcus aureus cap5O and cap5P genes functionally complement mutations affecting enterobacterial common-antigen biosynthesis in Escherichia coli; Kiser KB et al.; The Staphylococcus aureus cap5P and cap5O genes of the type 5 capsule biosynthetic locus restore enterobacterial common-antigen expression to Escherichia coli mutants defective in rffE and rffD gene expression, respectively . Cap5P and Cap5O likely function as UDP-GlcNAc 2-epimerase and UDP-ManNAc dehydrogenase enzymes, respectively, in the synthesis of the capsule precursor UDP-ManNAcA.

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