Pediatrics, 2003 Mar, 111(3), e269 - 74 Central venous catheter removal versus in situ treatment in neonates with enterobacteriaceae bacteremia; Nazemi KJ et al.; OBJECTIVE: To determine how often neonates with Enterobacteriaceae (ENTB) bacteremia can be treated successfully without removing central venous catheters (CVCs) . METHODS: A retrospective cohort study was conducted of ENTB bacteremia and CVCs in infants in a neonatal intensive care unit during a 7-year period (1994-2000) . Cases of ENTB bacteremia were identified from a microbiology database and limited to late-onset cases occurring after 3 days of age . RESULTS: There were 53 cases of ENTB bacteremia in infants with CVCs . Blood cultures were positive for ENTB within a median of 10 hours (range: 5-43) . Timing of CVC removal was at the discretion of attending neonatologists . Fifteen cases had early-removal CVC (ER-CVC) within 2 days, and 38 cases had late-removal CVC (LR-CVC) >2 days after the first positive blood culture for ENTB . There were no significant differences between infants in the ER-CVC and LR-CVC groups for case fatality, recurrence, or duration of ENTB bacteremia . Although 16 (42%) of 38 (95% confidence interval {CI}: 26%-59%) LR-CVC cases required CVC removal to resolve ENTB bacteremia, 17 (45%) of 38 (95% CI: 29%-62%) LR-CVC cases were treated successfully without removal of CVCs . ENTB bacteremia was successfully treated without CVC removal in 85% of 13 LR-CVC cases with 1 day of bacteremia in contrast to 24% of 25 LR-CVC cases with >1 day of bacteremia (relative risk: 3.5; 95% CI: 1.7-7.4) . CVC removal was required to resolve ENTB bacteremia in 9 (82%) of 11 LR-CVC cases with severe thrombocytopenia compared with 7 (32%) of 22 LR-CVC cases without severe thrombocytopenia (relative risk: 2.6; 95% CI: 1.3-5.0) . CONCLUSIONS: Retention of CVCs was successful in 45% of cases of ENTB bacteremia in which it was attempted, but success was unlikely when bacteremia lasted >1 day . ENTB bacteremia cases associated with severe thrombocytopenia rarely resolved unless CVCs were removed. Arch Esp Urol, 2002 Dec, 55(10), 288 - 93 Urinary tract infections in adult and adolescent males of a developing community: pattern, bacteriology and genito-urinary predisposing factors; Murshidi MS et al.; OBJECTIVES: Analysis of 95 consecutive adult and adolescent males with urinary tract infections to determine the pattern, bacteriology and the predisposing causes . METHODS: The period was 12 months, and the number of patients was 95 consecutive cases . They were adult and adolescent males with urinary tract infection . Their age ranged from 13-100 years, (median 55, mean 53.3 years) . RESULTS: Hospital and community acquired urinary tract infections occurred in 40% and 60% of patients respectively . E . coli was isolated from 66.7% of community acquired infections, which was well below the reported literature of 80-90% . CONCLUSIONS: Enterococci and Enterobacter spp . Appear to be emerging as important hospital and community acquired urinary tract pathogens in males . Bladder outflow obstruction accounted for over 50% of all genito urinary causes of urinary tract infections, while genitourinary malignancy occurred in nearly 20% of patients . The implications of these findings are discussed. Antimicrob Agents Chemother, 2003 Mar, 47(3), 1115 - 9 Mercury resistance determinants related to Tn21, Tn1696, and Tn5053 in enterobacteria from the preantibiotic era; Essa AM et al.; Three mer transposons from the Murray collection of preantibiotic enterobacteria show >99% sequence identity to current isolates . Tn5073 is most closely related to Tn5036 and Tn1696, and Tn5074 is most closely related to Tn5053 . Tn5075 is most closely related to Tn21 but lacks integron In2 and is flanked by insertion elements. Mol Microbiol, 2003 Mar, 47(5), 1445 - 57 A hexA homologue from Photorhabdus regulates pathogenicity, symbiosis and phenotypic variation; Joyce SA et al.; Photorhabdus is a genus of entomopathogenic Gram-negative bacteria that belong to the family Enterobactericeae . Remarkably, at the same time as being pathogenic to insect larvae, Photorhabdus also have a mutualistic relationship with entomophagous nematodes of the family Heterorhabditiae . Photorhabdus can be isolated in two phenotypically distinct forms, termed the primary and secondary variant . Both variants grow equally well and are equally virulent when injected into insect larvae . However, only the primary variant can colonize the intestinal tract of the IJ stage of the nematode and support nematode growth and development . The primary variant expresses several phenotypes that are absent from the secondary variant, including the production of extracellular enzymes, pigments, antibiotics and light . In this study, we use Photorhabdus temperata strain K122 to show that these primary-specific products are symbiosis factors, i.e . factors that are required for nematode growth and development . We also show that, in P . temperata K122, the production of these symbiosis factors is repressed in the secondary variant by the protein encoded by a gene with homology to hexA from Erwinia . Moreover, the derepression of the symbiosis factors in the secondary variant results in a significant attenuation of virulence to larvae of the greater wax moth, Galleria mellonella . This suggests that, during a normal infection, pathogenicity and symbiosis must be temporally separated and that HexA is involved in the regulation of this pathogen-symbiont transition. Mol Microbiol, 2003 Mar, 47(5), 1395 - 406 Regulation of Salmonella typhimurium lipopolysaccharide O antigen chain length is required for virulence; identification of FepE as a second Wzz; Murray GL et al.; Wzz proteins regulate the degree of polymerization of the O antigen (Oag) subunits in lipopolysaccharide (LPS) biosynthesis . Although the pathogenic relevance of Oag is well recognized, the significance of Oag chain length regulation is not well defined . In this report, Salmonella typhimurium was shown to possess two functional wzz genes resulting in a bimodal Oag length distribution . In addition to the previously described wzzST that results in long (L) modal length LPS with 16-35 Oag repeat units (RUs), we now report that wzzfepE, a homologue of Escherichia coli fepE, is responsible for the production of very long (VL) modal length LPS Oag, estimated to contain> 100 Oag RUs . Analysis of a series of isogenic S . typhimurium C5 mutants found that the presence of either wzz gene (and hence either modal length) was sufficient for complement resistance and virulence in the mouse model of infection, suggesting a degree of redundancy in the role of these two wzz genes and their respective Oag modal lengths . In contrast, the wzzST/wzzfepE double mutant, with relatively short, random-length Oag, displayed enhanced susceptibility to complement and was highly attenuated in the mouse . This clearly demonstrates the molecular genetic basis for the longer LPS Oag chains previously identified as the basis of complement resistance in Salmonella . The presence of wzzfepE homologues in the genomic sequences of strains of Escherichia coli, Shigella flexneri and multiple serovars of Salmonella suggests that bimodality of LPS Oag is a common phenomenon in the Enterobacteriaceae. Dis Mon, 2003 Feb, 49(2), 71 - 82 The etiology of urinary tract infection: traditional and emerging pathogens; Ronald A; The microbial etiology of urinary infections has been regarded as well established and reasonably consistent . Escherichia coli remains the predominant uropathogen (80%) isolated in acute community-acquired uncomplicated infections, followed by Staphylococcus saprophyticus (10% to 15%) . Klebsiella, Enterobacter, and Proteus species, and enterococci infrequently cause uncomplicated cystitis and pyelonephritis.The pathogens traditionally associated with UTI are changing many of their features, particularly because of antimicrobial resistance . The etiology of UTI is also affected by underlying host factors that complicate UTI, such as age, diabetes, spinal cord injury, or catheterization . Consequently, complicated UTI has a more diverse etiology than uncomplicated UTI, and organisms that rarely cause disease in healthy patients can cause significant disease in hosts with anatomic, metabolic, or immunologic underlying disease . The majority of community-acquired symptomatic UTIs in elderly women are caused by E coli . However, gram-positive organisms are common, and polymicrobial infections account for up to 1 in 3 infections in the elderly . In comparison, the most common organisms isolated in children with uncomplicated UTI are Enterobacteriaceae . Etiologic pathogens associated with UTI among patients with diabetes include Klebsiella spp., Group B streptococci, and Enterococcus spp., as well as E coli . Patients with spinal cord injuries commonly have E coli infections . Other common uropathogens include Pseudomonas and Proteus mirabilis.Recent advances in molecular biology may facilitate the identification of new etiologic agents for UTI . The need for accurate and updated population surveillance data is apparent, particularly in light of concerns regarding antimicrobial resistance . This information will directly affect selection of empiric therapy for UTI. Jpn J Antibiot, 2002 Sep, 55 Suppl A, 86 - 94 {Drug sensitivity and beta-lactamase producibility of various types of bacteria clinically isolated during the period from December 1999 to February 2000}; Hashimoto K et al.; beta-Lactamase activity and drug sensitivity were measured in 744 strains from 8 species of bacteria isolated at medical institutions in Chikugo District of Fukuoka Prefecture during the period from December 1999 to February 2000 . Nitrocefin test revealed that beta-lactamase was positive in 48% of S . aureus, 7% of H . influenzae, and 92% of M . catarrhalis, and acidometry revealed that penicillinase/cephalosporinase were positive in 13%/14% of E . coli, 22%/8% of K . pneumoniae, 47%/97% of E . cloacae, 3%/65% of S . marcescens, and 10%/36% of P . aeruginosa . Based on the assessment of the MIC values of various types of antibacterial drugs for beta-lactamase-producing strains, there were 11 strains (1 strain of K . pneumonia, 6 strains of E . cloacae, and 4 strains of P . aeruginosa) of class-B beta-lactamase-producing bacteria out of a total of 496 strains of Enterobacteriaceae and Pseudomonas aeruginosa . The results of PCR analysis suggested that 1 strain of K . pneumonia, 1 strain of E . cloacae, and 4 strains of P . aeruginosa produced metallo-beta-lactamase . There was no strain (E . coli and K . pneumoniae) of ESBL-producing bacteria . BLNAR strains, on the other hand, were found in 9% (9/100) of H . influenzae. Jpn J Antibiot, 2002 Sep, 55 Suppl A, 65 - 78 {Antimicrobial susceptibility and beta-lactamase types among clinical isolates during January and February 2000 in the Kinki area of Japan}; Yamasaki K et al.; We studied antimicrobial susceptibility and beta-lactamase types among clinical isolates in the Kinki area of Japan . Eight hundreds isolates of eight organisms were collected by seven medical institutions during January and February 2000 . The rates of beta-lactamase producing by using the chromogenic nitrocephin test were 68.0% against Staphylococcus aureus isolates, 6.0% against Haemophilus influenzae isolates, 98.0% against Moraxella catarrhalis isolates . The rate of beta-lactamase negative ampicillin-resistant H . influenzae was 4.0% (4 out of 100) . The result of beta-lactamase producing by using the acid-metric method were as follows the penicillinase and cephalosporinase: 27.0% and 37.0% against Escherichia coli isolates, 37.0% and 1.0% against Klebsiella pneumoniae isolates, 21.8% and 100% against Enterobacter cloacae isolates, 24.2% and 96.0% against Serratia marcescens isolates, 7.0% and 22.0% against Pseudomonas aeruginosa isolates . We identified beta-lactamase type of each isolate detected by polymerase chain reaction: SHV-derived extended-spectrum beta-lactamase (ESBLs) (1 isolate of E . coli and 1 isolate of K . pneumoniae), CTX-M-1-derived ESBLs (1 isolate of K . pneumoniae, 1 of E . cloacae and 4 of S . marcescens), and IMP-1-derived metallo beta-lactamases (2 isolates of S . marcescens). Jpn J Antibiot, 2002 Sep, 55 Suppl A, 54 - 64 {Antimicrobial susceptibility and beta-lactamase producibility of bacteria clinically isolated during the period from December 1999 to February 2000}; Abe M et al.; Antimicrobial susceptibility and beta-lactamase producibility were tested in 848 clinical strains collected at 8 hospitals in Kanagawa prefecture during the period from December 1999 to February 2000 . Positive rates of beta-lactamase used the nitrocefin method (Cefinase) were 21.9% of Staphylococcus aureus, 10.0% of Haemophilus influenzae, and 99.0% of Moraxella catarrhalis . Furthermore, on the acidometric method (P/Case test) penicillinase (PCase), cephalosporinase (CEPase), and both of PCase and CEPase were found to be positive in 19.0%, 16.0%, and 16.0% for Escherichia coli, 6.2/0/3.1% for Klebsiella pneumoniae, 0/66.3/26.5% for Enterobacter cloacae, 2.8/57.7/15.5% for Serratia marcescens, and 4.0/15.0/22.0% for Pseudomonas aeruginosa, respectively . Based on the assessment of minimal inhibitory concentrations (MICs) of antibacterial agents among beta-lactamase producing strains, there were 5 strains (4 strains of K . pneumoniae and 1 strain of E . coli) that may be ESBLs producing bacteria out of a total of 466 strains of Enterobacteriaceae and P . aeruginosa . During this process, 1 strain of class-B beta-lactamase-producing E . cloacae was isolated . MRSA were found in 79.2% of S . aureus, and BLNAR were found in 8.9% of H . influenzae. Jpn J Antibiot, 2002 Sep, 55 Suppl A, 42 - 53 {Antibiotic susceptibility and beta-lactamase activity of pathogenic microbes isolated in Miyagi Prefecture between December in 1999 and February in 2000}; Watanabe A et al.; We determined beta-lactamase activity and antimicrobial susceptibility of 556 strains consisting of 10 species isolated in four medical institutions and one microbiological laboratory of Miyagi Prefecture in Japan between December in 1999 and February in 2000 . beta-Lactamase determined by nitrocefin method was positive in 68% of S . aureus, in 15% of H . influenzae and in 100% of M . catarrhalis . Penicillinase/cephalosporinase determined by acidometry was positive in 9%/10% of E . coli, in 17%/2% of K . pneumoniae, in 16%/58% of E . cloacae, in 43%/78% of S . marcescens, and in 4%/32% of P . aeruginosa, respectively . Of a total of 298 strains of Enterobacteriaceae and P . aeruginosa, 25 strains (14 strains of E . coli, 10 strains of K . pneumoniae and one strain of S . marcescens) produced class A beta-lactamase, two strains of E . cloacae produced class B beta-lactamase, and 12 strains (one strain of E . coli, four strains of E . cloacae, six strains of S . marcescens and one strain of P . aeruginosa) produced class C beta-lactamase . According to NCCLS standard, three strains (one strain of E . coli and two strains of K . pneumoniae) of ESBL-positive microbes were detected . beta-Lactamase-negative ampicillin-resistant (BLNAR) strains of H . influenzae were found in 10/40 (25.0%) of the strains tested. Biotechnol Bioeng, 2003 May 5, 82(3), 370 - 7 Effect of specific oxygen uptake rate on Enterobacter aerogenes energetics: carbon and reduction degree balances in batch cultivations; Converti A et al.; The effect of oxygen availability on the metabolism of Enterobacter aerogenes NCIMB 10102 was studied through batch fermentations of glucose performed increasing the specific oxygen uptake rate up to 72.7 mmol(O2) C-mol(DW) (-1) x h(-1) . The final concentrations of fermentation products of this biosystem (2,3-butanediol, hydrogen, acetoin, formate, acetate, carbon dioxide, ethanol, lactate, succinate, and biomass) were utilized to check the use of simple carbon mass and reduction degree balances for the study of microbial energetics even in batch cultivations . J Food Prot, 2003 Feb, 66(2), 293 - 9 Bacteriology and storage life of moisture-enhanced pork; Bohaychuk VM et al.; This study was undertaken to determine the impact of the moisture enhancement process on the bacterial contamination and storage life of vacuum-packaged pork loins . Bone-in and boneless pork loins injected with brine (sodium chloride, sodium phosphate, lemon juice) were obtained from a commercial processing facility and stored for 5 weeks in vacuum packaging at 2 and 5 degrees C . At weekly intervals, samples were excised to determine numbers of spoilage bacteria and pathogens . The loins were subjectively evaluated by a sensory panel to quantify appearance and odor acceptability . Moisture-enhanced loins were initially contaminated with a population of psychrotrophic bacteria that was approximately 2 log units higher than that for noninjected boneless loins . This difference was largely due to contamination by larger numbers of pseudomonads in the brine-injected loins . There were no significant differences in the initial numbers of lactic acid bacteria, Enterobacteriaceae, or Brochothrix thermosphacta . Similar trends in spoilage bacterial populations were observed for moisture-enhanced loins with bones, but Enterobacteriaceae counts were also found to be approximately 1 log unit higher for the injected product . Brine-injected loins generally had larger bacterial numbers at each storage time, but there were no consistent injection treatment effects on bacterial growth . Brine injection did not affect color or odor deterioration, and the storage life for vacuum-packaged loins was the same as that for noninjected controls . The incidence of Listeria monocytogenes was 21% for control loins and 27% for moisture-enhanced loins . Although the brine injection process resulted in an increase in bacterial contamination, there was no evidence that this contamination would affect the storage life of vacuum-packaged loins, and further research is necessary to determine the significance of the increased incidence of L . monocytogenes. Surg Infect (Larchmt), 2001, 2 Suppl 1, S13 - 22 The importance of beta-lactamase resistance in surgical infections; Edmiston CE Jr et al.; Substantial costs are associated with the treatment of nosocomial infections, 2 million cases of which occur annually in the United States . Hospital-acquired, gram-negative infection has become an increasing problem, particularly in the intensive care unit where up to 40% of the most frequently isolated strains of Enterobacteriaceae are resistant to standard beta-lactam antibiotics . Among several mechanisms of acquisition of resistance, beta-lactamase production accounts for a high percentage of treatment failures and relapses . By the end of the 1980s, some 10-30% of all nosocomial infections were caused by type-1 beta-lactamase-producing gram-negative isolates, and Enterobacter species had emerged as a major resistant pathogen . The beta-lactam/beta-lactamase inhibitor combinations, such as ampicillin/sulbactam, represent an innovative approach to the problem of beta-lactamase-mediated resistance . Clinical use of these agents has been associated with low rates of resistance and new data suggest they may have a specific role in controlling the emergence and spread of nosocomial infections. Proc Natl Acad Sci U S A, 2003 Mar 4, 100(5), 2616 - 21 Epub 2003 Feb 19. Relish-mediated immune deficiency in the transgenic mosquito Aedes aegypti; Shin SW et al.; The lack of genetic means has been a serious limitation in studying mosquito immunity . We generated Relish-mediated immune deficiency (RMID) by transforming Aedes aegypti with the Delta Rel transgene driven by the vitellogenin (Vg) promoter using the pBac{3xP3-EGFP, afm} vector . A stable transformed line had a single copy of the Vg-Delta Rel transgene . The Vg-Delta Rel transgene expression was highly activated by blood feeding, and transgenic mosquitoes were extremely susceptible to the infection by Gram-negative bacteria . This RMID phenotype was characterized by severely reduced postinfection levels of antimicrobial peptides genes, defensin and cecropin . Crossing the RMID line with the wild-type strain produced the same RMID phenotype, indicating its dominant nature, whereas crossing with the Vg-def transgenic line, in which Defensin A was activated by blood feeding, restored the immunity to Enterobacter cloacae. FEMS Microbiol Lett, 2003 Feb 14, 219(1), 69 - 74 Intraspecies variability of Desulfovibrio desulfuricans strains determined by the genetic profiles; Dzierzewicz Z et al.; Fifteen (soil and intestinal) strains of Desulfovibrio desulfuricans species were typed by PCR method with the use of primers specific for repetitive extragenic palindromic (REP) and enterobacterial repetitive intergenic consensus (ERIC) sequences . As a result, characteristic DNA fingerprints for the strains were obtained . Moreover, the genetic profiles were found to be useful for typing and distinguishing the strains of D . desulfuricans . According to cluster analysis, PCR with primers complementary to the sequences REP appeared to be slightly more discriminatory than PCR with ERIC primers for the investigated strains . Distinct fingerprint patterns of two isolates derived from the same patient pointed to the different origin of both strains. Indian J Med Res, 2002 Aug, 116, 73 - 81 Phenotypic & genotypic variants of Pseudomonas aeruginosa isolated from children with cystic fibrosis in India; Agarwal G et al.; BACKGROUND & OBJECTIVES: Pseudomonas aeruginosa is the leading cause of morbidity and mortality in patients with cystic fibrosis (CF) . With increase in the chronicity of the disease, there is a diversification of the organism into different colony morphological types . The antimicrobial susceptibility of the organism varies with its colony morphology . The present work was carried out to study the different morphotypes of P . aeruginosa isolated from patients of cystic fibrosis . METHODS: We studied 38 children with CF attending the Paediatric Chest Clinic at the All India Institute of Medical Sciences, New Delhi, India during October 2000-January 2001 who were regularly followed up at the clinic . Patients were divided into 2 groups, Group 1 included all patients chronically infected with P . aeruginosa and Group 2 included patients who were infrequently colonized with this organism . Different colony morphological types of P . aeruginosa on culture media were identified . They were characterized by phenotypic methods using antibiograms and genotypic methods using enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction and PCR-ribotyping . RESULTS: Fourteen of the 38 patients were colonized at least once with P . aeruginosa . Eight patients belonged to Group 1 and 42 isolates were obtained from these patients . Group 2 had 6 patients and 9 isolates were obtained from them . All patients in Group 1 harboured different colony morphotypes (Types 1-6) while all 6 patients in Group 2 showed a single type of colony morphology (Type 1) . The isolates from Group 1 patients showed higher antimicrobial resistance as compared to Group 2 patients . Molecular typing of the isolates revealed 10 ERIC-PCR patterns and 2 PCR-ribotyping patterns among Group 1 and 2 ERIC-PCR and 1 PCR-ribotyping pattern among patients of Group 2 . INTERPRETATION & CONCLUSION: The frequency of different morphotypes of P . aeruginosa and antibiotic resistance was higher among Group 1 patients . On molecular typing, more than one genotype was isolated from Group 1 patients while only one genotype was isolated from patients in Group 2 . We conclude that at a given time, chronically infected patients can be colonized by phenotypically and genotypically distinct strains of P . aeruginosa which has an implication in the management of these patients. J Bacteriol, 2003 Mar, 185(5), 1634 - 41 Synthesis of a Klebsiella pneumoniae O-antigen heteropolysaccharide (O12) requires an ABC 2 transporter; Izquierdo L et al.; A recombinant clone encoding enzymes for Klebsiella pneumoniae O12-antigen lipopolysaccharide (LPS) was found when we screened for serum resistance of a cosmid-based genomic library of K . pneumoniae KT776 (O12:K80) introduced into Escherichia coli DH5alpha . A total of eight open reading frames (ORFs) (wb(O12) gene cluster) were necessary to produce K . pneumoniae O12-antigen LPS in E . coli K-12 . A complete analysis of the K . pneumoniae wb(O12) cluster revealed an interesting coincidence with the wb(O4) cluster of Serratia marcescens from ORF5 to ORF8 (or WbbL to WbbA) . This prompted us to generate mutants of K . pneumoniae strain KT776 (O12) and to study complementation between the two enterobacterial wb clusters using mutants of S . marcescens N28b (O4) obtained previously . Both wb gene clusters are examples of ABC 2 transporter-dependent pathways for O-antigen heteropolysaccharides . The wzm-wzt genes and the wbbA or wbbB genes were not interchangeable between the two gene clusters despite their high level of similarity . However, introduction of three cognate genes (wzm-wzt-wbbA or wzm-wzt-wbbB) into mutants unable to produce O antigen allowed production of the specific O antigen . The K . pneumoniae O12 WbbL protein performs the same function as WbbL from S . marcescens O4 in either the S . marcescens O4 or E . coli K-12 genetic background. Heart, 2003 Mar, 89(3), 263 - 8 Molecular diagnosis of culture negative infective endocarditis: clinical validation in a group of surgically treated patients; Grijalva M et al.; OBJECTIVE: To assess the clinical validity of polymerase chain reaction (PCR) based molecular methods in the microbiological diagnosis of culture negative infective endocarditis in a group of surgically treated patients . DESIGN: Retrospective case-control study . SETTING: Reference cardiovascular surgical centre . PATIENTS AND SAMPLES: 15 culture negative patients with infective endocarditis classified according to Duke criteria, with 17 heart valve samples; 13 age and sex matched control patients without infective endocarditis, with 13 valve samples . INTERVENTIONS: Medical records were reviewed and clinical, demographic, and microbiological data collected, including results of molecular detection of bacteria and fungi from valve samples . The clinical validity of molecular diagnosis was assessed, along with the sensitivity and speed of the systems . RESULTS: In the study group, 14 patients were PCR positive (93%) . Organisms detected were streptococci (3), staphylococci (2), enterobacter (1), Tropheryma whippelii (1), Borrelia burgdorferi (1), Candida albicans (1), and Aspergillus species (2) . Three cases were positive on universal bacterial detection but the pathogen could not be identified because of contaminating background . One case was negative . All but two positive cases showed clinical correlations . These two cases had no symptoms of infective endocarditis but there was agreement with the surgical findings . All control cases were PCR negative . Results were available within eight hours, and if sequencing was necessary, within 48 hours . CONCLUSIONS: PCR based molecular detection of pathogens in valve samples from surgically treated culture negative infective endocarditis patients is fast, sensitive, and reliable . The technology, combined with thorough validation and clinical interpretation, may be a promising tool for routine testing of infective endocarditis. J Laryngol Otol, 2003 Jan, 117(1), 43 - 51 Comparison of the efficacy and safety of moxifloxacin and trovafloxacin for the treatment of acute, bacterial maxillary sinusitis in adults; Klossek JM et al.; In this multicentre, multinational, comparative, double-blind clinical trial, out-patients with both symptoms and radiographic evidence of acute sinusitis were randomly assigned to receive either a seven-day, once daily (o.d.) oral regimen of moxifloxacin (400 mg) or a 10-day o.d . oral regimen of trovafloxacin (200 mg) . Among 452 patients considered valid for clinical efficacy, moxifloxacin treatment was found to be statistically equivalent to trovafloxacin (96.9 per cent vs 92.1 per cent -95 per cent CI = 0.6 per cent; 8.9 per cent) at the seven to 10 days post-therapy assessment . At follow-up, the success rate in the moxifloxacin group was 94.9 per cent and that for the trovafloxacin group was 97.6 per cent (95 per cent CI = -4.9 per cent; 1.3 per cent) . The predominant causative organisms were Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus followed by Enterobacteriaceae and Moraxella catarrhalis . The bacteriological success rate at the post-therapy evaluation was similar in both treatment groups: 94.4 per cent and 90.1 per cent in the moxifloxacin and trovafloxacin groups respectively (95 per cent CI = -3.0 per cent; 11.9 per cent) . Only three of the 103 baseline isolated pathogens still persisted in the moxifloxacin group, whereas there were 10 of the 121 isolates that failed to respond in the trovafloxacin treatment group . At least one drug-related event was reported by 16.9 per cent of the moxifloxacin-treated patients and by 22.3 per cent of those who received trovafloxacin . CNS events such as dizziness and vertigo were reported more than five times more often in patients receiving trovafloxacin than in the moxifloxacin group . Trovafloxacin recipients were also more than twice as likely to discontinue treatment due to adverse events than moxifloxacin-treated patients . Overall, moxifloxacin was at least as effective clinically and bacteriologically as trovafloxacin and better tolerated. Biochem Biophys Res Commun, 2003 Feb 21, 301(4), 985 - 90 Imipenem and expression of multidrug efflux pump in Enterobacter aerogenes; Bornet C et al.; Imipenem is often used to treat intensive care unit patients infected by Enterobacter aerogenes, but it is leading to an increasing number of antibiotic resistant strains . Clinical isolates and imipenem resistant variants presented a high level of resistance to beta-lactam antibiotic group and to chemically unrelated drugs . We report here that imipenem selects strains which contain active efflux pumps ejecting various unrelated antibiotics including quinolones, tetracycline, and chloramphenicol . An increase of AcrA, an efflux pump component, was observed in the imipenem resistant variants . The overexpression of marA, involved in the genetic control of membrane permeability via porin and efflux pump expression, indicated the activation of the resistance genetic cascade in imipenem resistant variants. J Hosp Infect, 2003 Feb, 53(2), 144 - 6 Timing and aetiology of bacterial infections in a liver intensive care unit; Wade J et al.; We undertook a prospective study of 887 consecutive adult patients admitted over an 11 year period to a liver intensive care unit . One or more bacterial infections occurred in 335 (37.8%) patients . Gram-positive cocci predominated . In relation to the date of admission these infections occurred in a statistically significant sequence . Streptococci infections were earliest (median time to infection two days), followed by Staphylococcus aureus (three days), coagulase-negative staphylococci (six days) and enterococci (eight days) . Escherichia coli infections occurred earlier than those due to klebsiella-enterobacter (two vs seven days; P = 0.0001) and, overall, Enterobacteriaceae earlier than non-fermentative Gram-negatives (four vs . eight days; P = 0.0081) . This study contributes to the management of high-dependency patients by confirming statistically the timing and sequence of infecting bacteria in patients with acute liver failure . J Hosp Infect, 2003 Feb, 53(2), 111 - 6 Nosocomial infections after cardiac surgery in infants and children: incidence and risk factors; Levy I et al.; This prospective study was undertaken to determine the spectrum, sites and main risk factors for hospital-acquired infections (HAI) in our paediatric cardiothoracic intensive care unit (PCICU), and to determine the main organisms causing bloodstream infection in this setting . All patients admitted between January and December 1999 were prospectively followed for the development of HAI . To define risk factors, patients were grouped by age, complexity score, length of stay in PCICU, and whether the patient's chest was open or closed postoperatively . Three hundred and thirty-five patients underwent cardiac surgery . Fifty-five patients acquired 69 HAIs (HAI patient rate 16.4%) . The most common HAI were bloodstream and surgical wound infection in 10 and 8%, respectively . The main causative organisms were Klebsiella spp.,Enterobacter spp . and Pseudomonas spp . in 22, 17 and 16% of episodes, respectively.Staphylococcus spp . accounted for 16% of episodes . The main risk factors for developing HAI were: neonatal age {P < 0.05, odds ratio (OR): 5.89, 95% confidence interval (CI): 2.96-11.58} prolonged PCICU stay (P < 0.05, OR: 6.82, 95% CI: 3.37-14.48), open chest postoperatively (P < 0.05, OR: 3.44, 95% CI: 1.31-8.52) and high complexity score (P < 0.05, OR: 4.03 95% CI: 1.87-8.43) . The main causative organisms of bloodstream infections in children hospitalized in the PCICU differ from those in adult and pediatric general intensive care units (ICUs) and include mainly Gram-negative bacilli . High complexity score, neonatal age, prolonged ICU stay, and open chest postoperatively are risk factors of HAI in this patient population . FEMS Microbiol Lett, 2003 Jan 28, 218(2), 333 - 8 Phenotypic evidence for inducible multiple antimicrobial resistance in Salmonella choleraesuis; Tibbetts RJ et al.; Multiple antimicrobial resistance (MAR) in Salmonella choleraesuis is becoming a major concern . It has been demonstrated that a MAR phenotype can be induced in Escherichia coli and other members of the Enterobacteriaceae by exposing the isolates to salicylates, various antimicrobials, or organic solvents used to combat and control bacterial infection . Therefore the purpose of the present study was to determine whether this marA-associated MAR-phenotype is inducible in S . choleraesuis . Isolates used in the present study were able to withstand toxic effects of the organic solvent cyclohexane naturally, or following exposure to the inducing compounds salicylate, tetracycline, or chloramphenicol . All isolates possessed fragments of marA with the predicted size of 408 bp when amplified using marA-specific primers by PCR . The resulting PCR products that were sequenced revealed that amplified S . choleraesuis marA was 99% and 85% homologous to the published Salmonella typhimurium and E . coli marA sequences respectively . Minimum inhibitory concentrations of tetracycline (P<0.08), chloramphenicol (P<0.001), rifampin (P<0.08), and nalidixic acid (P<0.001) against cyclohexane-tolerant mutants were significantly increased when compared with wild-type S . choleraesuis . Northern hybridization signals for both marA and acrB were increased in the induced isolates when compared to uninduced controls while soxS expression did not change between induced and uninduced cultures . The results suggest that marA is present in S . choleraesuis and a MAR-phenotype is inducible in S . choleraesuis presumably due to the overexpression of marA and acrB and not to the overexpression of soxS. FEMS Microbiol Lett, 2003 Jan 28, 218(2), 231 - 7 Genetic variability of the frameshift region in IS911 transposable elements from Escherichia coli clinical isolates; Licznar P et al.; The IS911 bacterial transposable element has been analyzed for its mechanism of transposition and for the way it controls the expression of its genes by programmed -1 translational frameshifting . In the present study the prevalence of IS911 has been determined in the Enterobacteriaceae family and in other Gram-negative bacilli . Three variants, found in Escherichia coli clinical isolates and having mutations in the region implicated in frameshifting, were functionally characterized . All three were altered in their frameshifting and transposition abilities, suggesting that the frameshift region of IS911 may constitute a target for mutations reducing the transposition frequency of this mobile element in natural populations of E . coli. Plasmid, 2003 Jan, 49(1), 79 - 85 Species differences in plasmid carriage in the Enterobacteriaceae; Sherley M et al.; Modern concerns about the spread of antibiotic resistance raise questions about the effect of bacterial species on plasmid evolution and maintenance . We studied 223 Enterobacteriaceae isolated from wild mammals and determined the number of plasmids per isolate, the size of those plasmids, and the distribution of plasmid incompatibility groups N, P, W, FII, and A/C . All of these variables were non-randomly distributed with respect to bacterial species, suggesting that host-cell factors constrain the plasmids that a strain will carry . The implication for the evolution of multiple-resistance plasmids in a clinical setting is that although inter-generic plasmid transfer may introduce a novel resistance plasmid into a bacterial genus, it is likely to be modified to suit the requirements of the new host cell . This then further suggests that resistance plasmids will evolve independent lineages within bacterial species although the genes incorporated in them may have come from the same original source . Indian J Pathol Microbiol, 2000 Jan, 43(1), 51 - 3 The mechanism of ampicillin resistance in enterobacteriaceae isolated in Vellore; Jesudason SM et al.; Ampicillin resistance in clinical isolates of enterobacteriaceae has been on the increase in the last decade . A study was carried out to delineate the possible mechanisms of this resistance . The method employed was isoelectric focussing to observe the electrophoretic mobility of the enzyme responsible and this showed that TEM 1 betalactamase was the cause irrespective of the species. Pneumologie, 2003 Feb, 57(2), 73 - 7 {Nosocomial pneumonias in haematological malignancies in the medical intensive care unit}; Hoheisel G et al.; 30 patients with malignant haematological disorders and nosocomial pneumonia, treated during a three-year period in the medical intensive care unit (ICU) of a university hospital, were studied in retrospect . Twelve patients had received bone marrow or peripheral stem cell transplantations 90 +/- 143 (10 - 546) days prior to ICU admission . Six of these received cyclosporin A . 19 of 30 patients were on corticosteroids and 20 had received courses of chemotherapy within a period of one month prior to ICU admission . Patients presented with signs of pulmonary infection and respiratory failure . In 24 patients the likely causative pathogen for pneumonia could be identified . Gram-negative bacteria (n = 17) were in the majority, lead by Pseudomonas, Enterobacter, and Klebsiella species . Gram-positive bacteria (n = 5) were Streptococcus and Staphylococcus species . Infections with Chlamydiae species were diagnosed in two cases . Fungal infections were caused by Candida (n = 8) or Aspergillus species (n = 3) and viral infections by Cytomegalovirus (n = 6) . Infections with more than one pathogen were common . Ten patients had pneumonia associated with signs of diffuse pulmonary parenchymal damage of varying degree . 26 patients received mechanical ventilation for 7 +/- 9 (1 - 32) days . The duration of stay in the ICU was 11 +/- 10 (1 - 43) days . 26 of the 30 patients (87 %) died . Patients with haematological malignancies and nosocomial pneumonias have despite medical intensive care treatment a poor prognosis with substantial mortality. Biochemistry, 2003 Feb 18, 42(6), 1529 - 36 Inhibition of beta-lactamases by monocyclic acyl phosph(on)ates; Kaur K et al.; The cyclic acyl phosph(on)ates, 1-hydroxy-5-phenyl-2,6-dioxaphosphorinone(3)-1-oxide, its 4-phenyl isomer, and the phosphonate (2-oxo) analogue of the latter inhibited typical class A (TEM-2) and class C (Enterobacter cloacae P99) beta-lactamases in a time-dependent fashion . No enzyme-catalyzed turnover was detected in any case . The interactions occurring were interpreted in terms of the reaction scheme E + I left arrow over right arrow EI left arrow over right arrow EI', where EI is a reversibly formed noncovalent complex, and EI' is a covalent complex . Reactions of the cyclic phosphates with the P99 beta-lactamase were effectively irreversible, while that of the 4-phenyl cyclic phosphate with the TEM beta-lactamase was slowly reversible . The 4-phenyl cyclic phosphate was generally the most effective inhibitor, both kinetically and thermodynamically, with second-order rate constants of inactivation of both enzymes around 10(4) s(-1) M(-1) . This compound also bound noncovalently to both enzymes, with dissociation constants of 25 microM from the P99 enzyme and 100 microM from the TEM . It is unusual to find an inhibitor equally effective against the TEM and P99 enzymes; the beta-lactamase inhibitors currently employed in medical practice (e.g., clavulanic acid) are significantly more effective against class A enzymes . The results of lysinoalanine analysis after hydroxide treatment of the inhibited enzymes and of a (31)P nuclear magnetic resonance spectrum of one such complex were interpreted as favoring a mechanism of inactivation by enzyme acylation rather than phosphylation . Molecular modeling of the enzyme complexes of the 4-phenyl phosphate revealed bound conformations where recyclization and thus reactivation of the enzyme would be difficult . The compounds studied were turned over slowly or not at all by acetylcholinesterase and phosphodiesterase I. New Microbiol, 2003 Jan, 26(1), 27 - 32 Antimicrobial resistance of animal and human strains of Enterobacteriaceae in Greece; Burriel AR et al.; Two hundred sixty two strains of Enterobacteriaceae from animal and human sources where intermixing and/or spreading is possible were examined for their resistance to 15 antimicrobials frequently used in animal prophylaxis and metaphylaxis . The antimicrobials with the highest proportion of resistant strains from animal sources were amoxicillin 25 mg, colistin sulphate 25 mg, erythromycin 5 mg, penicillin G 10 mg and spectinomycin 10 mg . The same with isolates from human sources where ampicillin 10 mg, amoxicillin 25 mg, colistin sulphate 25 mg, erythromycin 5 mg, neomycin 10 mg, penicillin G 10 mg and spectinomycin 10 mg . Human isolates were resistant to more antimicrobials than animal isolates . Common a high proportion of isolates from both sources were resistant to some antimicrobials . Systematic and better distributed information is needed to address the epidemiological role of veterinary treatment, prophylaxis and metaphylaxis in antimicrobial resistance in Greece. Crit Care Med, 2003 Feb, 31(2), 419 - 27 Multicenter evaluation of a human monoclonal antibody to Enterobacteriaceae common antigen in patients with Gram-negative sepsis; Albertson TE et al.; OBJECTIVE: To evaluate in Gram-negative sepsis patients the human monoclonal immunoglobulin M antibody (MAB-T88) directed at the enterobacterial common antigen which is a specific surface antigen closely linked to lipopolysaccharide and shared by all members of the Enterobacteriaceae family of Gram-negative bacteria . DESIGN: Prospective, randomized, double-blinded, placebo-controlled, multicenter trial . SETTING: Thirty-three academic medical centers in the United States . PATIENTS: Patients were entered with a clinical diagnosis of sepsis, the presence of either shock or multiple organ dysfunction, and presumptive evidence for Gram-negative infection . INTERVENTIONS: Patients received a single intravenous infusion, over 30 mins, of either 300 mg of MAB-T88 formulated in albumin, or placebo (albumin) . MEASUREMENTS AND MAIN RESULTS: The primary analysis group was prospectively identified as those patients with documented evidence of an infection with bacteria of the family Enterobacteriaceae at any site . The primary end point was survival within the first 28 days . A total of 826 patients were enrolled with 55% (n = 455) in the primary analysis group . There were no significant differences between the intervention and control primary analysis group study groups for sites of infection, severity of illness, underlying medical conditions, adequacy of antibiotic or surgical treatment, or other baseline variables except for a higher frequency of chronic renal failure in the MAB-T88 group (4.4% vs . 1.3%, p=.051) . The average Acute Physiology and Chronic Health Evaluation II scores were 26.8 +/- 8.6 (mean +/- sd) in the MAB-T88-treated group and 26.5 +/- 8.3 in the placebo-treated group (p =.72) . There was no significant difference between MAB-T88- and placebo-treated groups during the first 28-day all-cause mortality in the primary analysis group (34.2% vs . 30.8%, p=.44) or in all 826 patients enrolled (37.0% vs . 34.0%, p=.36) . On subset analysis, the use of MAB-T88 was not associated with significant mortality trends . More adverse events were seen with the use of MAB-T88 in the bacteremic enterobacterial common antigen group (p <.05) . CONCLUSIONS: Use of the human monoclonal antibody, MAB-T88, did not improve the mortality in patients with presumed Gram-negative sepsis or in those patients with proven enterobacterial common antigen infections . No subset trends were identified that would support further investigation of this agent in sepsis. Hunan Yi Ke Da Xue Xue Bao, 2002 Feb 28, 27(1), 77 - 8 {Extended-spectrum beta-lactamase detection in Enterobacteriaceae and antibiotic susceptibility analysis}; Cao W et al.; OBJECTIVE: To detect the extended-spectrum beta-lactamases (ESBLs) in family Enterobacteriaceae and analyze the antibiotic susceptibility of those ESBLs-producing strains . METHODS: ESBLs were determined by the double-disk confirmatory test and 8 antibiotic susceptibilities were tested with the disk disffusion method in those strains producing ESBLs . RESULTS: Forty-seven ESBLs-producing strains comprised of 25 of E . coli, 14 of K . pneumoniae, 5 of E . cloacae, 1 of K . oxytoca, 1 of K . rhinoscleromatis, and 1 of S . liquefaciens . The susceptibility rates of those strains were: 100% for imipenem and meropenem, 89.4% for piperacillin/tazobactam, 72.4% for cefoxitin and 65.9% for cefotetan . CONCLUSION: E . coli and K . pneumoniae are the prime strains producing ESBLs in Enterobacteriaceae . Imipenem and meropenem are the best drugs to deal with those ESBLs-producing strains . Piperacillin/tazobactam is better than cephamycins and other beta-lactama/beta-lactamase inhibitor combination. Zhong Yao Cai, 1999 Aug, 22(8), 408 - 11 {Studies on the anti-enteropathogenic bacteria action of Herba Pogostemonis extracts}; Liu H et al.; The results of antimicrobial test in vitro of water-extracts and volatile oil of the Herba Pogostemonis shown that the water-extracts posses some inhibitory activity on all the tested bacteria, including Salmonella, Escherichia coli, Shigella flexneri and Staphylococcus aureus, while inhibition to S . aureus is more stronger than to Enterobacteriaceae (P < 0.01) . In addition, the activity of anti-enteropathogens of water-extracts of the herb collected from Gaoyao county is more stronger than of the herb collected from Wuchuan county (P < 0.01). Appl Environ Microbiol, 2003 Feb, 69(2), 1114 - 20 Differential inactivation of seed exudate stimulation of Pythium ultimum sporangium germination by Enterobacter cloacae influences biological control efficacy on different plant species; Kageyama K et al.; This study was initiated to understand whether differential biological control efficacy of Enterobacter cloacae on various plant species is due to differences in the ability of E . cloacae to inactivate the stimulatory activity of seed exudates to Pythium ultimum sporangium germination . In biological control assays, E . cloacae was effective in controlling Pythium damping-off when placed on the seeds of carrot, cotton, cucumber, lettuce, radish, tomato, and wheat but failed to protect corn and pea from damping-off . Seeds from plants such as corn and pea had high rates of exudation, whereas cotton and cucumber seeds had much lower rates of exudation . Patterns of seed exudation and the release of P . ultimum sporangium germination stimulants varied among the plants tested . Seed exudates of plants such as carrot, corn, lettuce, pea, radish, and wheat were generally more stimulatory to P . ultimum than were the exudates of cotton, cucumber, sunflower, and tomato . However, this was not directly related to the ability of E . cloacae to inactivate the stimulatory activity of the exudate and reduce P . ultimum sporangium germination . In the spermosphere, E . cloacae readily reduced the stimulatory activity of seed exudates from all plant species except corn and pea . Our data have shown that the inability of E . cloacae to protect corn and pea seeds from Pythium damping-off is directly related to its ability to inactivate the stimulatory activity of seed exudates . On all other plants tested, E . cloacae was effective in suppressing damping-off and inactivating the stimulatory activity of seed exudates. Int J Fertil Womens Med, 2002 Nov-Dec, 47(6), 265 - 70 Positive bacterial culture of semen from infertile men with asymptomatic leukocytospermia; Esfandiari N et al.; OBJECTIVE: To examine results of semen culture in a population of infertile men with asymptomatic leukocytospermia, and to determine the correlation between culture results and sperm characteristics in these patients . METHODS: Semen samples were collected from a group of infertile men (n = 80) after 2-3 days of sexual abstinence . Standard semen analysis was performed according to World Health Organization (WHO) guidelines . Seminal leukocyte concentrations were determined by a myeloperoxidase staining technique . Culture of semen was performed on enriched and specific culture media . RESULTS: Based on the results of semen culture, the samples were classified into three groups: group 1 (enteric gram-negative bacilli {Enterobacteriaceae}, n = 13), group 2 (bacteria other than Enterobacteriaceae, n = 15), and group 3 (negative cultures, n = 52) . No correlation was found between positive semen culture and sperm characteristics (concentration, motility, and morphology) . However, seminal leukocyte concentrations were negatively correlated with percentages of motile sperm and normal sperm morphology . CONCLUSION: Our data indicate that semen samples from infertile men with asymptomatic leukocytospermia may have bacterial contamination, evidenced by positive bacterial cultures . Lack of correlation between positive semen cultures and sperm characteristics may be indicative of early or mild (subclinical) infection. Cell Mol Life Sci, 2002 Dec, 59(12), 2055 - 64 The role of conjugative transposons in the Enterobacteriaceae; Pembroke JT et al.; Although widely studied in gram-positive Streptococci and in the gram-negative Bacteroides, there is a scarcity of information on the occurrence and nature of conjugative transposon-like elements in the well-studied Enterobacteriaceae . In fact, some of the major reviews on conjugative transposons prior to 1996 failed to mention their occurrence in this group . Recently, their presence has been reported in Salmonella, Vibrio and Proteus species, and in some cases such as the SXT element in Vibrio and the IncJ group element CTnR391, there has been some molecular characterization . The elements thus far examined appear to be larger than the common gram-positive conjugative transposons and to be mosaic in structure, with genes derived from several sources . Recent evidence suggests that in the Enterobacteriaceae the elements may be related to enteric pathogenicity islands . The evolution, distribution and role of these elements in the Enterobacteriaceae is discussed. Arch Esp Urol, 2002 Nov, 55(9), 1165 - 79 {Urinary tract infection in pregnancy and menopause}; Broseta Rico E et al.; OBJECTIVES: To review the topic of urinary tract infections (UTI) during pregnancy and menopause . UTI during pregnancy and menopause have great relevance in the field of urologic infections; during pregnancy because of the particularities involved in its diagnosis and treatment and potential consequences to the fetus and mother; menopausal UTI because this group of women is numerous and represents a growing section of the general population pyramid, due to the aging of population in developed countries associated with longer life expectancies and grater demand for quality of life . METHODS AND RESULTS: We performed a bibliographic review combined with our personal experience . During pregnancy there are several functional and anatomical changes that condition not only a higher risk of UTI, but also an additional treatment difficulty due to antimicrobial pharmacokinetics alterations and potential damage to the fetus . Despite efforts to find an easy, fast and reliable test for bacteriuria detection, urine culture continues to be the first diagnostic test for its detection and follow up during pregnancy . Penicillin derivates and cephalosporins continue to be the first choice because their lack of adverse effects on either fetus or mother . Alternative options like phosphomicin and aztreonam although they show low toxicity there is need for more studies supporting their suitability for the treatment of pregnancy UTIs . Menopausal female UTI have their different features from those in younger women . Hormonal alterations derived from gonadal atrophy associate functional changes in the vaginal ecosystem, making it prone to enterobacteriaceae colonization as a first step up to the urinary tract . This associated with genitourinary tract anatomical alterations inherent t aging make UTI extraordinary prevalent in this growing segment of population . Treatment lines focus on hormonal alteration correction and proper antimicrobial prophylaxis and vaccines in a close future . CONCLUSIONS: UTIs during pregnancy and menopause have differential features that require different diagnostic and treatment approaches. J Antimicrob Chemother, 2003 Feb, 51(2), 459 - 62 Tissue and serum concentrations of levofloxacin 500 mg administered intravenously or orally for antibiotic prophylaxis in biliary surgery; Swoboda S et al.; OBJECTIVES: Levofloxacin is a third-generation fluoroquinolone with a broad spectrum of antibacterial activity, comprising enterobacteria, non-fermenters, Gram-positive cocci and some anaerobic species . Members of these species are common pathogens in acute and chronic cholecystitis . This suggests that levofloxacin may be used as peri-operative prophylaxis in gall-bladder surgery . The purpose of our study was to determine serum and tissue levels of levofloxacin in cholecystectomy patients following pre-operative dosing . PATIENTS AND METHODS: Patients with gall-bladder surgery were given levofloxacin 500 mg as a single dose either intravenously (iv) or orally pre-operatively, at the treating physician's decision . Gall-bladder tissue and serum samples were collected, and drug concentrations were determined by HPLC with fluorescence detection . Additionally, all tissue samples underwent routine microbiological diagnostics . MICs for aerobic isolates were determined using the Etest . RESULTS: A total of 61 patients (48 female, 13 male) were included . The medians of the levofloxacin concentrations in serum were 11.37 mg/L (iv) and 9.65 mg/L (oral), and in gall-bladder tissue they were 15.61 mg/kg (iv) and 17.93 mg/kg (oral) . Eleven pathogens were isolated from gall-bladder samples . Post-operative wound infection was observed in two of the 61 patients . CONCLUSION: Our data suggest that levofloxacin may be considered for peri-operative prophylaxis in biliary tract surgery. J Antimicrob Chemother, 2003 Feb, 51(2), 397 - 400 Characterization of a new integron containing VIM-2, a metallo- beta-lactamase gene cassette, in a clinical isolate of Enterobacter cloacae; Jeong SH et al.; We report the first description of a new integron containing bla(VIM-2), a metallo-beta-lactamase gene from Enterobacter cloacae KU680, which was isolated from peritoneal fluid of a liver cirrhosis patient in South Korea . Antibiotic susceptibility testing, and modified Hodge and EDTA-disc synergy tests, were carried out to screen for metallo-beta-lactamase-producing strains . PCR and sequence analysis were used to identify and analyse the bla(VIM-2)-containing integron . The isolate was resistant to most beta-lactams, including imipenem, and demonstrated a positive modified Hodge and EDTA-disc synergy test, which are findings suggesting a metallo-beta-lactamase . Preliminary PCR-based experiments detected the metallo-beta-lactamase gene bla(VIM-2) . Sequencing of the 4392 bp cloned PCR amplicon, containing the gene cassette bla(VIM-2), revealed the structure of the class 1 integron . The integron also contained additional insert gene cassettes, aadA, and unknown open reading frames 'orfII' and 'orfIII' . To the best of our knowledge, this is the first time that this metallo-beta-lactamase gene has been detected in E . cloacae. J Antimicrob Chemother, 2003 Feb, 51(2), 317 - 21 Prevalence and types of class 1 integrons in aminoglycoside-resistant Enterobacteriaceae from several Chilean hospitals; Reyes A et al.; Members of the family Enterobacteriaceae are responsible for a variety of nosocomial infections, treatment of which is limited due to their increasing resistance to antibiotics . Some bacterial genes encoding antibiotic resistance comprise the major part of gene cassettes, most of which are associated with integrons . In this work, the carriage of class 1, 2 and 3 integrons was investigated in 191 Enterobacteriaceae isolates from clinical specimens of hospitalized patients . Class 1 integrons were found to be the most common, whereas no class 3 integrons were detected . The variable regions of 13 class 1 integrons were characterized and four types were found . Type 1 harbours only ant(3")I, type 2 harbours ant(2")I and ant(3")I, type 3 harbours aac(6')Ib and ant(3")I and type 4 lacks inserted gene cassettes. Drugs, 2003, 63(4), 353 - 65 Extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae: considerations for diagnosis, prevention and drug treatment; Rupp ME et al.; Extended spectrum beta-lactamase (ESBL)-producing organisms pose unique challenges to clinical microbiologists, clinicians, infection control professionals and antibacterial-discovery scientists . ESBLs are enzymes capable of hydrolysing penicillins, broad-spectrum cephalosporins and monobactams, and are generally derived from TEM and SHV-type enzymes . ESBLs are often located on plasmids that are transferable from strain to strain and between bacterial species . Although the prevalence of ESBLs is not known, it is clearly increasing, and in many parts of the world 10-40% of strains of Escherichia coli and Klebsiella pneumoniae express ESBLs . ESBL-producing Enterobacteriaceae have been responsible for numerous outbreaks of infection throughout the world and pose challenging infection control issues . Clinical outcomes data indicate that ESBLs are clinically significant and, when detected, indicate the need for the use of appropriate antibacterial agents . Unfortunately, the laboratory detection of ESBLs can be complex and, at times, misleading . Antibacterial choice is often complicated by multi-resistance . Many ESBL-producing organisms also express AmpC beta-lactamases and may be co-transferred with plasmids mediating aminoglycoside resistance . In addition, there is an increasing association between ESBL production and fluoroquinolone resistance . Although in in vitro tests ESBLs are inhibited by beta-lactamase inhibitors such as clavulanic acid, the activity of beta-lactam/beta-lactamase inhibitor combination agents is influenced by the bacterial inoculum, dose administration regimen and specific type of ESBL present . Currently, carbapenems are regarded as the drugs of choice for treatment of infections caused by ESBL-producing organisms . Unfortunately, use of carbapenems has been associated with the emergence of carbapenem-resistant bacterial species such as Stenotrophomonas sp . or Pseudomonas sp. Wei Sheng Wu Xue Bao, 2002 Apr, 42(2), 236 - 41 {The solubilization of four insoluble phosphates by some microorganisms}; Zhao X et al.; Four insoluble phosphates of ferric phosphate (Fe-P), aluminum phosphate (Al-P), fluorapatite (FAP) and rock phosphate (RP) were used as a sole phosphorus resource for some phosphate-solubilizing microorganisms . It was found that there was significant difference in solubilizing these phosphates by the tested isolates . The fungi normally were more powerful than the bacteria in dissolving the phsophates . The microorganisms generally solubilized more phosphate when supplied with NO3- than with NH4+ . However, the isolates of 2TCiF2 and 4TCiF6 had much higher capacity to solubilize FAP and Al-P respectively in NH4+ medium . Most of the isolates solubilized readily FAP and RP, and then Al-P . Ferric phosphate was the least soluble to these isolates . Only isolate 2TCiF2 showed strong ability to solubilize Fe-P . In particular, two Aspergillus sp . had much higher capacity of dissolving Fe-P when suppled with NO3- . The isolates of Evwinia sp . 4TCRi22 and Enterobacter sp . 1TCRi15 had higher capacity of solubilizing FAP . But two Arthrobacter sp . showed the highest activity in RP medium . It is supposed that complexion of organic acids with metals may be the main reason for these isolates to solubilize the phosphates . However, other chelant substances may be much more important for Enterobacter sp . and Erwinia sp . to release phosphorus from the phsphates. Phytother Res, 2003 Jan, 17(1), 60 - 5 The comparative effect of novel Pelargonium essential oils and their corresponding hydrosols as antimicrobial agents in a model food system; Lis-Balchin M et al.; Essential oils and their corresponding hydrosols, obtained after distillation of various scented Pelargonium (Geraniaceae) leaves were assessed for their antimicrobial activity in a model food system . Both the essential oils and hydrosols were used at 1000 ppm in broccoli soup, previously inoculated with Enterobacter aerogenes (at 10(5) cfu g(-1)) and Staphylococcus aureus (at 10(4) cfu g(-1)) . The results showed a complete inhibition of S . aureus in the broccoli soup by the essential oils of 'Sweet Mimosa', 'Mabel Grey', P . graveolens, 'Atomic Snowflake', 'Royal Oak', 'Attar of Roses' and a lesser effect by 'Chocolate Peppermint' and 'Clorinda'; the hydrosols, however, had a potentiating effect on the bacterial population in the food . Both extracts showed a complete inhibition of S . aureus in the Maximum Recovery Diluent (MRD) . Antibacterial activity against E . aerogenes in the broccoli soup was generally very much reduced: only the essential oil of 'Mabel Grey' showed complete inhibition and virtually no reductions in colonies were seen with the other essential oils; the hydrosols again caused an increase in bacterial colonies . All the essential oils, bar Chocolate Peppermint showed complete inhibition of E . aerogenes in MRD, but the hydrosols showed no effect . The results strongly suggest that the residual hydrosols from distillation of these plant essential oils have no potential as antibacterial agents in foods, in contrast to most of the essential oils, which show potential against some micro-organisms, but only in some food systems . The problem of food component interference and its possible management is discussed . J Biol Chem, 2003 Apr 11, 278(15), 12779 - 85 Epub 2003 Jan 29. Purification and characterization of PrbA, a new esterase from Enterobacter cloacae hydrolyzing the esters of 4-hydroxybenzoic acid (parabens); Valkova N et al.; The esterase PrbA from Enterobacter cloacae strain EM has previously been shown to confer additional resistance to the esters of 4-hydroxybenzoic acid (parabens) to two species of Enterobacter . The PrbA protein has been purified from E . cloacae strain EM using a three-step protocol resulting in a 60-fold increase in specific activity . The molecular mass of the mature enzyme was determined to be 54,619 +/- 1 Da by mass spectrometry . It is highly active against a series of parabens with alkyl groups ranging from methyl to butyl, with K(m) and V(max) values ranging from 0.45 to 0.88 mM and 0.031 to 0.15 mM/min, respectively . The K(m) and V(max) values for p-nitrophenyl acetate were 3.7 mM and 0.051 mM/min . PrbA hydrolyzed a variety of structurally analogous compounds, with activities larger than 20% relative to propyl paraben for methyl 3-hydroxybenzoate, methyl 4-aminobenzoate, or methyl vanillate . The enzyme showed optimum activity at 31 degrees C and at pH 7.0 . PrbA was able to transesterify parabens with alcohols of increasing chain length from methanol to n-butanol, achieving 64% transesterification of 0.5 mm propyl paraben with 5% methanol within 2 h . PrbA was inhibited by 1-chloro-3-tosylamido-4-phenyl-2-butanone and 1-chloro-3-tosylamido-7-amino-2-heptanone (TLCK), with K(i) values of 0.29 and 0.20 mM, respectively, and was irreversibly inhibited by Diisopropyl fluorophosphate (DFP) or diethyl pyrocarbonate . The stoichiometry of addition of DFP to the enzyme was 1:1 and only 1 TLCK molecule was found in TLCK-modified enzyme, as measured by mass spectrometry . Analysis of the tryptic digest of the DFP-modified PrbA demonstrated that the addition of a DFP molecule occurred at Ser-189, indicating the location of the active serine. Wei Sheng Wu Xue Bao, 1999 Aug, 39(4), 296 - 304 {Genetic diversity among Chinese peanut rhizobia by rep-PCR analysis}; Li J et al.; Repetitive sequences(repetitive extragenic palindromic{REP}, and enterobacterial repetitive intergenic consensus {ERIC}) with the polymerase chain reaction(PCR) were used to fingerprint pure DNA extracted from 79 bradyrhizobial strains . These strains included 59 peanut rhizobia {Bradyrhizobium sp . (Arachis)} isolated from root nodules of 24 peanut (Arachis hypogaea L) cultivars from 23 sites in 11 provinces in China, 6 peanut rhizobial strains from other nations, and 14 reference strains of other bradyrhizobia . All the strains were clustered at the level of 11%, 2%, and 11, 24 clusters were obtained at the similarity of 50% with REP-PCR and ERIC-PCR fingerprints, respectively . The results showed that significant genomic diversity exists within the peanut rhizobia from China . Also they suggested that there are different distributions of REP and ERIC in genomic DNA of the peanut rhizobia . The combined results, REP plus ERIC data, were found between the both above . The genomic diversity seems not to correlate with their host and geographic origins . Our results supported this technique is a useful tool for genotypic characterization and identification of rhizobia as well as ecological studies. Arch Tierernahr, 2002 Dec, 56(6), 419 - 29 Influence of a probiotic Enterococcus faecium strain on selected bacterial groups in the small intestine of growing turkey poults; Vahjen W et al.; A feeding trial was carried out with turkey poults, which were fed a diet containing 10(10) viable probiotic E . faecium NCIB 10415 cells/kg feed . Samples of the intestinal tract were analyzed for lactate, colony forming units of total anaerobic bacteria, lactic acid bacteria, enterobacteria and enterococci . Furthermore, metabolic activity of total eubacterial, lactobacilli and enterococci was recorded in selected RNA-extracts with specific ribosomal RNA oligonucleotide probes . Animals fed the probiotic diet showed continously increasing lactate concentrations throughout the sampling period up to day 42 of life . No correlation was found for colony forming units (cfu) of lactic acid bacteria, but metabolic activity of lactobacilli showed very close relation to continously increasing lactate concentrations . Throughout the feeding trial, enterococci in the control group continously increased to a maximum of 10(4) cfu/g wet weight, but 10-fold higher enterococci cfu were generally found in the treated group . However, rRNA content as measure for metabolic activity showed a drastic decline in both groups after high metabolic activities on day 7 . This study shows that E . faecium NCIB 10415 (E . faecium SF68) stimulates other lactic acid bacteria in the small intestine, especially lactobacilli. Wei Sheng Wu Xue Bao, 2001 Dec, 41(6), 686 - 92 {Expression of the chiA gene from Serratia marcescens in both strain E26 and strain NG13, nitrogen-fixing bacteria associated with rice root}; Ye Z et al.; A 1.8 kb HinfI fragment carrying the chitinase gene (chiA) from Serratia marcescens was cloned into the expression vector pKK223-3 and the plasmid pMC71A, yielded the plasmid pKChiA and the plasmid pMChiA respectively . Both plasmid pKChiA and plasmid pMChiA were used to transform to the Enterobacter cloacae strain E26 and the Klebsiella oxytoca strain NG13, two nitrogen-fixing bacteria associated with rice root . The chiA gene could be highly expressed in the ChiA+ transformants of the strain E26 or the strain NG13 . Cell location determination of the expressed chitinase showed that the enzyme existed not only in cell periplasm and cytoplasm, but also in extracellular broth . When the cultures were in the aftor logarithmic growthe phase, the distribution of the enzyme activity in extracellular broth, periplasm and cytoplasm were 23%-28%, 45%-51% and 21%-32%, respectively . The molecular weight of chitinase expressed in the ChiA+ transformants was 58 kD by SDS-PAGE analysis . The stability of the plasmid pMChiA in the transformants was better than that of the plasmid pKChiA. J Infect Dis, 2003 Jan 15, 187(2), 251 - 9 Epub 2002 Dec 30. Multidrug resistance among Enterobacteriaceae is strongly associated with the presence of integrons and is independent of species or isolate origin; Leverstein-van Hall MA et al.; This study investigated the extent to which multidrug resistance (MDR) among Enterobacteriaceae is related to DNA elements called "integrons," whether the relationship is species dependent or origin dependent, and which resistance patterns are associated with integrons . Analysis of 867 nonrepeat isolates comprising 8 species and originating from the community and 23 European hospitals showed a significant relation between MDR and integrons, independent of species or origin . Although resistance to each tested antimicrobial agent was significantly associated with integrons, only resistance to sulfamethoxazole, cotrimoxazole, gentamicin, tobramycin, ampicillin, piperacillin, and cefuroxime predicted the presence of integrons . Combined resistance to both ampicillin and sulfamethoxazole-trimethoprim was the starting point for the development of resistance to additional beta-lactams, aminoglycosides, cephalosporins, and ciprofloxacin, a development paralleled by an increasing prevalence of integrons . The acquisition of resistance genes is not random, and the transfer of integron-carrying elements plays a dominant role in the development of MDR by Enterobacteriaceae. Wei Sheng Wu Xue Bao, 2001 Feb, 41(1), 82 - 6 {Purification and properties of chitinase from Enterobacter aerogenes}; Tang Y et al.; A bacterium producing chitinase was isolated from the dead body of Gymephorap ruoergensis . A chitinase was isolated from the culture of E . aerogenes and purified by means of ammonium sulfate precipitation, DEAE-cellulose column chromatography, and Sephadex G-100 column gel filtration . The purified chitinase showed homogeneity on the native polyacrylamide gel electrophoresis . Its molecular weight was estimated to be about 42.5 kD by SDS-PAGE . The optimum pH and temperature for hydrolysis of chitin were 6.0 and 55 degrees C respectively . Michaelis constant was 2.88 mg/mL . Different metal ions showed different effects on the chitinase activity, The chitinase activity was enhanced by Zn2+, Ba2+, Ca2+, Mn2+ and was strongly inhibited by Hg2+, Co2+, Mg2+. J Mol Biol, 2003 Feb 7, 326(1), 21 - 33 Complete nucleotide sequence of carbazole/dioxin-degrading plasmid pCAR1 in Pseudomonas resinovorans strain CA10 indicates its mosaicity and the presence of large catabolic transposon Tn4676; Maeda K et al.; The car and ant operons originally isolated from Pseudomonas resinovorans strain CA10 contain the genes encoding the carbazole/dioxin-degrading enzymes and anthranilate 1,2-dioxygenase, respectively, and are located on the plasmid pCAR1 . The entire nucleotide sequence of pCAR1 was determined to elucidate the mechanism by which the car operon may have been assembled and distributed in nature . pCAR1 is a 199,035-bp circular plasmid, and carries 190 open reading frames . Although the incompatibility group of pCAR1 is unclear, its potential origin for replication, OriP, and Rep and Par proteins appeared to be closely related to those of plasmid pL6.5 isolated from Pseudomonas fluorescens . The potential tellurite-resistance klaABC genes identified in the neighboring region of repA gene were also related to those in IncP plasmid originally identified from pseudomonads . On the other hand, we found genes encoding proteins that showed low but significant homology (20-45% identity) with Trh and Tra proteins from Enterobacteriaceae, which are potentially involved in conjugative transfer of plasmids or genomic island, suggesting that pCAR1 is also a conjugative plasmid . In pCAR1, we found tnpAcCST genes that encoded the proteins showing >70% length-wise identities with those are encoded by the toluene/xylene-degrading transposon Tn4651 of TOL plasmid pWW0 . Both car and ant degradative operons were found within a 72.8-kb Tn4676 sequence defined by flanking tnpAcC and tnpST genes and bordered by a 46-bp inverted repeat (IR) . Within Tn4676 and its flanking region, we found the remnants of numerous mobile genetic elements, such as the duplicated transposase genes that are highly homologous to tnpR of Tn4653 and the multiple candidates of IRs for Tn4676 and Tn4653-like element . We also found distinct regions with high and low G+C contents within Tn4676, which contain an ant operon and car operon, respectively . These results suggested that multiple step assembly could have taken place before the current structure of Tn4676 had been captured. Antimicrob Agents Chemother, 2003 Feb, 47(2), 816 - 9 Levofloxacin and ciprofloxacin in vitro activities against 4,003 clinical bacterial isolates collected in 24 Italian laboratories; Gesu GP et al.; Levofloxacin showed comparable in vitro susceptibility to ciprofloxacin among Enterobacteriaceae, Pseudomonas aeruginosa, enterococci, and Staphylococcus aureus, while greater susceptibility was observed in Stenotrophomonas maltophilia and Staphylococcus epidermidis, mainly when oxacillin resistant . The susceptibility of Streptococcus pneumoniae to levofloxacin reached 99%. Diagn Microbiol Infect Dis, 2002 Dec, 44(4), 379 - 82 Antimicrobial activity of broad-spectrum agents tested against Gram-negative bacilli resistant to ceftazidime: report from the SENTRY Antimicrobial Surveillance Program (North America, 2001); Jones RN et al.; To assess the effect of ceftazidime resistance on the activity of other antimicrobial agents, 4,175 Gram-negative bacilli isolates, designated as ceftazidime-susceptible (3,759, 90%) or -resistant (416, 10%) were tested against a panel of nine agents . Cefepime was the most active of the agents tested, against both ceftazidime-susceptible and -resistant isolates, with a particularly low incidence (0.3%, 10/3152 isolates) of resistance among the Enterobacteriaceae . Tobramycin had the best activity against Pseudomonas aeruginosa and ticarcillin/clavulanate was the least active of the tested agents . This study confirms the need for constant monitoring of in vitro antimicrobial efficacy to direct empiric treatment regimens. Diagn Microbiol Infect Dis, 2002 Dec, 44(4), 367 - 77 Evaluation of the in vitro activity of six broad-spectrum beta-lactam antimicrobial agents tested against recent clinical isolates from India: a survey of ten medical center laboratories; Mathai D et al.; The widespread use of beta-lactam antimicrobial agents as first-line therapy for the treatment of serious infections has led to the development of various resistances that have compromised the use of some agents . In certain countries, the lack of local or national surveillance programs limits the ability to detect these resistant strains and prevent their dissemination . A 10 medical center study in India was initiated to benchmark prevailing resistance rates for a range of bacterial pathogens to beta-lactams, and it found high rates of beta-lactamase-mediated resistance in Escherichia coli and Klebsiella spp . These rates included: cephalosporins (55.6-61.3% resistance), with extended-spectrum beta-lactamase (ESBL) phenotypes noted in over 60% of E . coli isolates and in Salmonella spp . (3.2-8.1%) . Imipenem, a carbapenem, was the only antimicrobial agent tested with 100% activity against Enterobacteriaceae . Cefpirome was the most active of the tested cephalosporins, and all were fully active against methicillin-susceptible staphylococci with the exception of ceftazidime . Molecular and susceptibility characterization of 52 selected ESBL-producing strains showed a high level of co-resistance with aminoglycosides and fluoroquinolones, and clonal dissemination of resistant strains within medical centers . Collaborative studies, such as those presented here, can accurately detect changes in resistance patterns, and their continued use may help limit the further development and spread of bacterial resistances in India. Eur J Biochem, 2003 Feb, 270(3), 440 - 50 Endotoxic activity and chemical structure of lipopolysaccharides from Chlamydia trachomatis serotypes E and L2 and Chlamydophila psittaci 6BC; Heine H et al.; The lipopolysaccharide (LPS) of Chlamydia trachomatis serotype E was isolated from tissue culture-grown elementary bodies and analyzed structurally by mass spectrometry and 1H, 13C and 31P nuclear magnetic resonance . The LPS is composed of the same pentasaccharide bisphosphate alphaKdo-(2-8)-alphaKdo-(2-4)-alphaKdo-(2-6)-betaGlcN-4P-(1-6)-alphaGlcN-1P (Kdo is 3-deoxy-alpha-d-manno-oct-2-ulosonic acid) as reported for C . trachomatis serotype L2{Rund, S., Lindner, B., Brade, H . and Holst, O . (1999) J . Biol . Chem . 274, 16819-16824} . The glucosamine disaccharide backbone is substituted with a complex mixture of fatty acids with ester or amide linkage whereby no ester-linked hydroxy fatty acids were found . The LPS was purified carefully (with contaminations by protein or nucleic acids below 0.3%) and tested for its ability to induce proinflammatory cytokines in several readout systems in comparison to LPS from C . trachomatis serotype L2 and Chlamydophila psittaci strain 6BC as well as enterobacterial smooth and rough LPS and synthetic hexaacyl lipid A . The chlamydial LPS were at least 10 times less active than typical endotoxins; specificity of the activities was confirmed by inhibition with the LPS antagonist, B1233, or with monoclonal antibodies against chlamydial LPS . Like other LPS, the chlamydial LPS used toll-like receptor TLR4 for signalling, but unlike other LPS activation was strictly CD14-dependent. Childs Nerv Syst, 2003 Jan, 19(1), 57 - 9 Epub 2002 Sep 04. Neonatal brain abscess--potential pitfalls of CT scanning; Sidaras D et al.; CASE REPORT . A 6-day-old preterm infant collapsed on the neonatal unit and was found to have enterobacter meningitis . Cranial ultrasounds had been normal in the first few days of life, but an ultrasound on day 9 of life showed a well-defined lesion, which was thought to be an abscess in view of his underlying illness . This finding could not be confirmed on CT scanning, which showed oedematous frontal lobes with a lack of grey-white differentiation . OUTCOME . The correct diagnosis and treatment were delayed until a follow-up CT scan showed more typical features of an abscess 4 days later. Proc Natl Acad Sci U S A, 2003 Feb 4, 100(3), 839 - 44 Epub 2003 Jan 21. Sodium ion cycling mediates energy coupling between complex I and ATP synthase; Gemperli AC et al.; We show here sodium ion cycling between complex I from Klebsiella pneumoniae and the F(1)F(0) ATP synthase from Ilyobacter tartaricus in a reconstituted proteoliposome system . In the course of NADH oxidation by complex I, an electrochemical sodium ion gradient was established and served as a driving force for the synthesis of ATP from ADP and phosphate . In the opposite direction, the deltamu(Na(+)) generated by ATP hydrolysis could be coupled to NADH formation by reversed electron transfer from ubiquinol to NAD . For reverse electron transfer, a transmembrane voltage larger than 30 mV was obligatory . No NADH-driven proton transport into the lumen of proteoliposomes was detected . We conclude that Na(+) is used as the exclusive coupling ion by the enterobacterial complex I. J Appl Microbiol, 2003, 94(2), 289 - 94 Antibiotic resistance and genotyping of clinical group B Salmonella isolated in Accra, Ghana; Mills-Robertson F et al.; AIMS: The purpose of this study was to investigate the antibiotic resistance and clonal lineage of serogroup B Salmonella isolated from patients suspected of suffering from enteric fever in Accra, Ghana . METHODS AND RESULTS: Serogroup B Salmonella were isolated from blood (n=28), cerebral spinal fluid (CSF) (n=1), or urine (n=2), and identified based on standard biochemical testing and agglutinating antisera . Isolates were examined for their susceptibility to ampicillin, chloramphenicol, tetracycline and trimethoprim-sulfamethoxazole . Most of the isolates could be classified as multiple-drug resistant . Furthermore, the genetic location of resistance genes was shown to be on conjugative plasmids . Genetic fingerprinting by plasmid profiling, enterobacterial repetitive intergenic consensus (ERIC)-PCR, and repetitive element (REP)-PCR were performed to determine the diversity among the isolates . Plasmid profiling discriminated five unique groupings, while ERIC-PCR and REP-PCR resulted in two and three groupings, respectively . CONCLUSIONS: A high rate of antibiotic resistance was associated with the Salmonella isolates and the genes responsible for the resistance are located on conjugative plasmids . Also, there appears to be minimal diversity associated with the isolates . SIGNIFICANCE AND IMPACT OF THE STUDY: As a result of the increasing antibiotic resistance among bacteria of all genera, surveys to monitor microbial populations are critical to determine the extent of the problem . The inability to treat many infectious diseases with current antibiotic regimens should prompt the medical community to be more prudent with its antibiotic use. J Bacteriol, 2003 Feb, 185(3), 1059 - 70 Traffic at the tmRNA gene; Williams KP; A partial screen for genetic elements integrated into completely sequenced bacterial genomes shows more significant bias in specificity for the tmRNA gene (ssrA) than for any type of tRNA gene . Horizontal gene transfer, a major avenue of bacterial evolution, was assessed by focusing on elements using this single attachment locus . Diverse elements use ssrA; among enterobacteria alone, at least four different integrase subfamilies have independently evolved specificity for ssrA, and almost every strain analyzed presents a unique set of integrated elements . Even elements using essentially the same integrase can be very diverse, as is a group with an ssrA-specific integrase of the P4 subfamily . This same integrase appears to promote damage routinely at attachment sites, which may be adaptive . Elements in arrays can recombine; one such event mediated by invertible DNA segments within neighboring elements likely explains the monophasic nature of Salmonella enterica serovar Typhi . One of a limited set of conserved sequences occurs at the attachment site of each enterobacterial element, apparently serving as a transcriptional terminator for ssrA . Elements were usually found integrated into tRNA-like sequence at the 3' end of ssrA, at subsites corresponding to those used in tRNA genes; an exception was found at the non-tRNA-like 3' end produced by ssrA gene permutation in cyanobacteria, suggesting that, during the evolution of new site specificity by integrases, tropism toward a conserved 3' end of an RNA gene may be as strong as toward a tRNA-like sequence . The proximity of ssrA and smpB, which act in concert, was also surveyed. J Bacteriol, 2003 Feb, 185(3), 991 - 1000 Characterization of SrgA, a Salmonella enterica serovar Typhimurium virulence plasmid-encoded paralogue of the disulfide oxidoreductase DsbA, essential for biogenesis of plasmid-encoded fimbriae; Bouwman CW et al.; Disulfide oxidoreductases are viewed as foldases that help to maintain proteins on productive folding pathways by enhancing the rate of protein folding through the catalytic incorporation of disulfide bonds . SrgA, encoded on the virulence plasmid pStSR100 of Salmonella enterica serovar Typhimurium and located downstream of the plasmid-borne fimbrial operon, is a disulfide oxidoreductase . Sequence analysis indicates that SrgA is similar to DsbA from, for example, Escherichia coli, but not as highly conserved as most of the chromosomally encoded disulfide oxidoreductases from members of the family Enterobacteriaceae . SrgA is localized to the periplasm, and its disulfide oxidoreductase activity is dependent upon the presence of functional DsbB, the protein that is also responsible for reoxidation of the major disulfide oxidoreductase, DsbA . A quantitative analysis of the disulfide oxidoreductase activity of SrgA showed that SrgA was less efficient than DsbA at introducing disulfide bonds into the substrate alkaline phosphatase, suggesting that SrgA is more substrate specific than DsbA . It was also demonstrated that the disulfide oxidoreductase activity of SrgA is necessary for the production of plasmid-encoded fimbriae . The major structural subunit of the plasmid-encoded fimbriae, PefA, contains a disulfide bond that must be oxidized in order for PefA stability to be maintained and for plasmid-encoded fimbriae to be assembled . SrgA efficiently oxidizes the disulfide bond of PefA, while the S . enterica serovar Typhimurium chromosomally encoded disulfide oxidoreductase DsbA does not . pefA and srgA were also specifically expressed at pH 5.1 but not at pH 7.0, suggesting that the regulatory mechanisms involved in pef gene expression are also involved in srgA expression . SrgA therefore appears to be a substrate-specific disulfide oxidoreductase, thus explaining the requirement for an additional catalyst of disulfide bond formation in addition to DsbA of S . enterica serovar Typhimurium. Intensive Care Med, 2003 Jan, 29(1), 49 - 54 Epub 2002 Dec 10. Rational use of antibiotics in the intensive care unit: impact on microbial resistance and costs; Geissler A et al.; OBJECTIVE: To evaluate the impact of an intensive care unit (ICU) antibiotic-use policy on the microbial resistance in nosocomial infections and costs . DESIGN: Comparative study before and after policy implementation . SETTINGS: An eleven-bed ICU in a general hospital . PATIENTS: All patients admitted for at least 48 h during a 5year period (1994-1998) . INTERVENTIONS: In 1995, implementation of an antibiotic-use policy . MEASUREMENTS AND MAIN RESULTS: Patients' general characteristics, incidence of nosocomial infections, antibiotic-selective pressure (the number of days of antibiotic treatment for 1,000 days of presence in the ICU), presence and types of multi-resistant micro-organisms and costs linked to antibiotic use were recorded before (1994) and after implementation of the policy (1995-1998) . For each year, patients' general characteristics and the incidence of nosocomial infections were the same . Costs linked to antibiotics use showed a progressive reduction (100% for 1994, 81% for 1995, 65% for 1998) . Antibiotic-selective pressure diminished (from 940 days of antibiotic use per 1,000 days (1994) to 610 (1998), p<10(-5)) . A statistically significant reduction in nosocomial infections due to antimicrobial resistant micro-organisms was observed (from 37% (1994) to 15% (1998) of nosocomial infections, p<10(-5)) after 3 years of implementation of the policy, essentially due to a reduction in methicillin-resistant Staphylococcus aureus and ceftriaxone-resistant Enterobacteriaceae . Nosocomial infections due to ceftazidime-resistant Pseudomonas species or extended-spectrum ss-lactamase Enterobacteriaceae showed no reduction . CONCLUSIONS: Antibiotic-use policy allowed a reduction in antibiotic-selective pressure, costs linked to antibiotics and selective reduction of nosocomial infections due to antimicrobial resistant micro-organisms. Nucleic Acids Res, 2003 Jan 15, 31(2), 743 - 9 Esp1396I restriction-modification system: structural organization and mode of regulation; Cesnaviciene E et al.; Esp1396I restriction-modification (RM) system recognizes an interrupted palindromic DNA sequence 5'-CCA(N)(5)TGG-3' . The Esp1396I RM system was found to reside on pEsp1396, a 5.6 kb plasmid naturally occurring in Enterobacter sp . strain RFL1396 . The nucleotide sequence of the entire 5622 bp pEsp1396 plasmid was determined on both strands . Identified genes for DNA methyltransferase (esp1396IM) and restriction endonuclease (esp1396IR) are transcribed convergently . The restriction endonuclease gene is preceded by the small ORF (esp1396IC) that possesses a strong helix-turn-helix motif and resembles regulatory proteins found in PvuII, BamHI and few other RM systems . Gene regulation studies revealed that C.Esp1396I acts as both a repressor of methylase expression and an activator of regulatory protein and restriction endonuclease expression . Our data indicate that C protein from Esp1396I RM system activates the expression of the Enase gene, which is co-transcribed from the promoter of regulatory gene, by the mechanism of coupled translation. Eur J Clin Microbiol Infect Dis, 2002 Dec, 21(12), 849 - 55 Epub 2002 Dec 11. Prevalence and drug susceptibility of pathogens causing bloodstream infections in northern Italy: a two-year study in 16 hospitals; Luzzaro F et al.; The epidemiology of bacterial pathogens causing bloodstream infection was studied in 16 hospitals in Lombardy (northern Italy) over a 2-year period (1999 and 2000) . Overall, 2924 microorganisms causing significant bacteremia were collected . The most frequent isolates were Escherichia coli ( n=663; 22.7%), Staphylococcus aureus ( n=534; 18.3%), Staphylococcus epidermidis ( n=242; 8.2%), and Pseudomonas aeruginosa ( n=176; 6.0%) . Unlike Escherichia coli, which was usually acquired from the community, Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa were usually acquired in hospitals . Rates of resistance to oxacillin and its associated traits were significantly higher among hospital-acquired staphylococci as compared to those of isolates from the community . Escherichia coli was highly susceptible to extended-spectrum cephalosporins, with a very low percentage of strains producing extended-spectrum ss-lactamases (ESBLs) . On the contrary, production of ESBL appeared to be an important mechanism of resistance among nosocomial isolates of Klebsiella pneumoniae . Resistance to ciprofloxacin was widespread in several members of the family Enterobacteriaceae, with rates often exceeding 10% . Moreover, with regard to ciprofloxacin, there were no significant differences between rates of resistance among Enterobacteriaceae causing hospital-acquired infections versus those causing community-acquired infections . Multidrug resistance was commonly observed in Pseudomonas aeruginosa, indicating the need for new antimicrobial agents that are more active against nonfermentative gram-negative bacteria . In conclusion, epidemiological studies of the prevalence and antimicrobial susceptibility patterns of blood isolates in northern Italy appear to provide useful information for both empirical treatment of suspected infections and better management of patients. Zh Mikrobiol Epidemiol Immunobiol, 2002 Sep-Oct, (5), 86 - 91 {Types of secretion and regulation of the functional activity of molecules associated with the pathogenicity of Enterobacteriaceae}; Bondarenko VM et al.; Five types of nonhomologous systems of the export of protein molecules, known to exist in pathogenic bacteria, are characterized . The described secretion systems take part in the synthesis of not only toxic proteins, but also different adhesins and hydrolytic enzymes . In the export of Enterobacteriaceae toxins secretion types I, II, III and V are of importance . Characteristics of Sec-dependence at the stage of transport through the cytoplasmic membrane is the key sign in their differentiation . The functional activity of bacterial toxins and the level of toxigenicity expression are finely regulated signs, mediated by external signals . The systems for their regulation are relatively few in number and rather conservative . As shown in this study, the regulation of pathogenicity expression has no specific mechanisms . Moreover, it is regulated by common systems and mechanisms for the regulation of usual physiological processes. Microb Drug Resist, 2002 Winter, 8(4), 393 - 9 Resistance to quaternary ammonium compounds in food-related bacteria; Sidhu MS et al.; Microbial resistance to antimicrobial agents continues to be a major problem . The frequent use and misuse of disinfectants based on quaternary ammonium compounds (QACs) in food-processing industries have imposed a selective pressure and may contribute to the emergence of disinfectant-resistant microorganisms . A total number of 1,325 Gram-negative isolates (Escherichia coli, other coliforms Vibrio spp., and Aeromonas spp.) and 500 Enterococcus spp . from food and food-processing industries and fish farming were screened for natural resistance to the QAC-based disinfectant benzalkonium chloride (BC) . Of the 1,825 isolates, 16 strains, mainly from meat retail shops, showed low-level resistance to BC . None of the Enterococcus spp . from broiler, cattle, and pigs, the antibiotic-resistant E . coli from pig intestine and fish pathogens Vibrio spp . and Aeromonas spp . from the Norwegian fish farming industry were resistant to BC . The BC-resistant strains were examined for susceptibility to 15 different antibiotics, disinfectants, and dyes . No systematic cross-resistance between BC and any of the other antimicrobial agents tested was detected . Stable enhanced resistance in Enterobacter cloacae isolates was demonstrated by step-wise adaptation in increasing concentrations of BC . In conclusion, BC resistance among food-associated Gram-negative bacteria and Enterococcus spp . is not frequent, but resistance may develop to user concentrations after exposure to sublethal concentrations of BC. Vopr Pitan, 2002, 71(6), 29 - 34 {Detection and serological screening of conditionally-pathogenic enterobacteria isolated from food products and the environment}; Efimochkina NR et al.; The spread of some coliform bacteria in foods, the faeces of children and adults and in human environment was studied, and the evaluation of their toxigenic potential and serological properties was given . More then 160 strains of enterobacteria including 70 strains of Escherichia spp were described . The frequency of detection enterotoxigenic E . coli in foods--18%--was approximately similar an amount of ETEC strains which was isolated in humans (22%) . 3 strains of E . coli) 157 were found in foods and in clinical samples (1.9%) . The observed results have confirmed the proposal about the increasing of ETEC E . coli food-borne transmitting and dissemination its in the environment. J Trop Pediatr, 2002 Dec, 48(6), 373 - 7 Bacteremia in childhood cancer; Celkan T et al.; Infection-related mortality affects the overall survival rates of children who are receiving treatment for cancer . The leading cause of mortality is bacteremia and sepsis related to it in febrile neutropenic patients . All positive blood cultures of febrile neutropenic patients treated in the Department of Pediatric Hematology-Oncology, Cerrahpasa Medical School, between January 1995 and January 2001 were reviewed . Cultures grew 159 micro-organisms, 95 (60 per cent) of which were Gram-positive bacteria, 56 (35 per cent) were Gram-negative bacteria and eight (5 per cent) were fungi . Coagulase-negative staphylococci (63, 40 per cent) and S . aureus (8, 5 per cent) were the most frequent Gram-positive pathogens . Klebsiella, E . coli, Enterobacter and Pseudomonas infections were the primary Gram-negative pathogens . Twenty cases were lost because of sepsis: in 11 cases (55 per cent) Gram-negative bacteria, in eight cases (40 per cent) Gram-positive bacteria, and in only one case a fungus were the causative organisms . Although vancomycin was not included in the first-line treatment, the mortality rate of Gram-positive bacteremia was 8 per cent . In Gram-negative bacteremia it was 20 per cent . Gram-negative pathogens, which were resistant to multiple antibiotics, caused the mortality . Drug resistance and mortality due to micro-organisms must be taken into consideration while febrile neutropenia protocols are prepared. Nucleic Acids Res, 2003 Jan 1, 31(1), 147 - 51 ASAP, a systematic annotation package for community analysis of genomes; Glasner JD et al.; ASAP (a systematic annotation package for community analysis of genomes) is a relational database and web interface developed to store, update and distribute genome sequence data and functional characterization . ASAP facilitates ongoing community annotation of genomes and tracking of information as genome projects move from preliminary data collection through post-sequencing functional analysis . The ASAP database includes multiple genome sequences at various stages of analysis, corresponding experimental data and access to collections of related genome resources . ASAP supports three levels of users: public viewers, annotators and curators . Public viewers can currently browse updated annotation information for Escherichia coli K-12 strain MG1655, genome-wide transcript profiles from more than 50 microarray experiments and an extensive collection of mutant strains and associated phenotypic data . Annotators worldwide are currently using ASAP to participate in a community annotation project for the Erwinia chrysanthemi strain 3937 genome . Curation of the E . chrysanthemi genome annotation as well as those of additional published enterobacterial genomes is underway and will be publicly accessible in the near future. Clin Exp Immunol, 2003 Jan, 131(1), 34 - 40 CD4+ T regulatory cells from the colonic lamina propria of normal mice inhibit proliferation of enterobacteria-reactive, disease-inducing Th1-cells from scid mice with colitis; Gad M et al.; Adoptive transfer of CD4+ T cells into scid mice leads to a chronic colitis in the recipients . The transferred CD4+ T cells accumulate in the intestinal lamina propria (LP), express an activated Th1 phenotype and proliferate vigorously when exposed ex vivo to enteric bacterial antigens . As LP CD4+ T cells from normal BALB/c mice do not respond to enteric bacterial antigens, we have investigated whether colonic LP-derived CD4+ T cells from normal mice suppress the antibacterial response of CD4+ T cells from scid mice with colitis . LP-derived CD4+ T cells cocultured with bone marrow-derived dendritic cells effectively suppress the antibacterial proliferative response of CD4+ T cells from scid mice with colitis . The majority of these LP T-reg cells display a nonactivated phenotype and suppression is independent of antigen exposure, is partly mediated by soluble factor(s) different from IL-10 and TGF-beta, and is not prevented by the addition of high doses of IL-2 to the assay culture . Functionally and phenotypically the T-reg cells of the present study differ from previously described subsets of T-reg cells . The presence of T cells with a regulatory potential in the normal colonic mucosa suggests a role for these cells in the maintenance of local immune homeostasis of the gut. Cancer, 2003 Jan 15, 97(2), 419 - 24 Ciprofloxacin prophylaxis in patients with acute leukemia and granulocytopenia in an area with a high prevalence of ciprofloxacin-resistant Escherichia coli; Gomez L et al.; BACKGROUND: Infection remains the major cause of morbidity and mortality in patients with neutropenia, and the beneficial effects of oral prophylaxis remain controversial . METHODS: From 1993 to December 1999, the authors analyzed the clinical and microbiologic outcomes of 144 episodes of febrile neutropenia among adult patients with acute leukemia . RESULTS: Forty-three consecutive episodes occurred among patients who were on ciprofloxacin prophylaxis during 1993-1996 (ciprofloxacin group), and 101 subsequent episodes occurred among patients who were not exposed to ciprofloxacin prophylaxis (control group) . There were no differences in clinical presentation, antibiotic treatment received for the episode, or a worse outcome between groups . The rate of bacteremia was similar (12 of 43 patients {28%} vs . 26 of 101 patients {26%}, respectively) . There was a trend toward a higher rate of Gram positive bacteremia in the control group (12 of 101 patients {12%} vs . 2 of 43 patients {5%}) and a higher rate of Gram negative bacteremia in the ciprofloxacin group (11 of 43 patients {26%} vs . 15 of 101 patients {15%}) . Resistance to fluoroquinolones was greater in Escherichia coli blood isolates from patients in the ciprofloxacin group (7 of 8 patients vs . 2 of 9 patients; P = 0.02) . CONCLUSIONS: The current results suggest that fluoroquinolone prophylaxis for patients with febrile neutropenia may be abandoned safely in areas with a high prevalence of ciprofloxacin-resistant enterobacteria . J Clin Microbiol, 2003 Jan, 41(1), 351 - 8 Antimicrobial susceptibility testing of carbapenems: multicenter validity testing and accuracy levels of five antimicrobial test methods for detecting resistance in Enterobacteriaceae and Pseudomonas aeruginosa isolates; Steward CD et al.; From January 1996 to May 1999, Project ICARE (Intensive Care Antimicrobial Resistance Epidemiology) received 448 nonduplicate clinical isolates of Enterobacteriaceae and Pseudomonas aeruginosa that were reported to be imipenem intermediate or resistant . However, broth microdilution (BMD) confirmatory testing at the Project ICARE central laboratory confirmed this result in only 11 of 123 (8.9%) Enterobacteriaceae isolates and 241 of 325 (74.2%) P . aeruginosa isolates . To investigate this overdetection of imipenem resistance, we tested 204 selected isolates from the Project ICARE collection plus five imipenem-resistant challenge strains at the Centers for Disease Control and Prevention against imipenem and meropenem by agar dilution, disk diffusion, Etest (AB BIODISK North America, Inc., Piscataway, N.J.), two MicroScan WalkAway conventional panels (Neg MIC Plus 3 and Neg Urine Combo 3) (Dade MicroScan, Inc., West Sacramento, Calif.), and two Vitek cards (GNS-116 containing meropenem and GNS-F7 containing imipenem) (bioMerieux Vitek, Inc., Durham, N.C.) . The results of each test method were compared to the results of BMD testing using in-house-prepared panels . Seven imipenem-resistant and five meropenem-resistant isolates of Enterobacteriaceae and 43 imipenem-resistant and 21 meropenem-resistant isolates of P . aeruginosa were identified by BMD . For Enterobacteriaceae, the imipenem and meropenem test methods produced low numbers of very major and major errors . All test systems in the study produced low numbers of very major and major errors when P . aeruginosa was tested against imipenem and meropenem, except for Vitek testing (major error rate for imipenem, 20%) . Further testing conducted in 11 of the participating ICARE hospital laboratories failed to pinpoint the factors responsible for the initial overdetection of imipenem resistance . However, this study demonstrated that carbapenem testing difficulties do exist and that laboratories should consider using a second, independent antimicrobial susceptibility testing method to validate carbapenem-intermediate and -resistant results. J Clin Microbiol, 2003 Jan, 41(1), 213 - 7 Comparison of recovery of blood culture isolates from two BacT/ALERT FAN aerobic blood culture bottles with recovery from one FAN aerobic bottle and one FAN anaerobic bottle; Riley JA et al.; Traditionally, a routine blood culture for adult patients consisted of paired aerobic and anaerobic bottles, but the routine use of an anaerobic blood culture bottle has been challenged in recent years . In this study, we compared the recovery of two FAN aerobic bottles with one FAN aerobic and one FAN anaerobic bottle . Each pair of bottles was collected by a separate collection procedure, and each bottle held a recommended 8- to 12-ml draw . A total of 704 clinically significant isolates were recovered from 8,620 sets (17,240 pairs), with 487 (69.2%) isolates recovered from one or both bottles in each pair of bottles, 86 isolates (12.2%) recovered only from the FAN aerobic-FAN aerobic pair, and 131 isolates (18.6%) recovered only from the FAN aerobic-FAN anaerobic pair . Significantly more total organisms (P = 0.002), gram-positive cocci (P = 0.03), Staphylococcus aureus (P = 0.05), Enterobacteriaceae other than Escherichia coli (P = 0.02), and anaerobes (P = 0.01) were recovered from the FAN aerobic-FAN anaerobic pair than from the FAN aerobic-FAN aerobic pair . A separate analysis was performed on the 618 isolates that were recovered from the FAN aerobic-FAN anaerobic pair to compare recovery by bottle type . Significantly more S . aureus (P = 0.005) and anaerobes (P < 0.001) were recovered from the FAN anaerobic bottle, while significantly more coagulase-negative staphylococci (P = 0.01), Streptococcus pneumoniae (P = 0.03), and other gram-negative bacilli (P = 0.004) were recovered from the FAN aerobic bottle . These results support the routine use of a FAN anaerobic bottle for use in the culture of blood with the BacT/ALERT system in our institution . These results also suggest that the decision of whether to routinely utilize an anaerobic blood culture bottle should be influenced by the overall recovery of bacteria and yeast, the recovery of specific types of bacteria or yeast, the medium type, and the blood culture system utilized by the laboratory. Infect Control Hosp Epidemiol, 2002 Dec, 23(12), 721 - 4 Surveillance of hemodialysis-associated primary bloodstream infections: the experience of ten hospital-based centers; Dopirak M et al.; OBJECTIVE: To determine baseline rates of primary bloodstream infection (BSI) among a large pool of patients receiving hemodialysis using standardized surveillance tools and methodology . DESIGN: Prospective, descriptive analysis of primary BSI rates . SETTING: Ten hospital-based hemodialysis centers in Connecticut . PATIENTS: All patients receiving long-term hemodialysis in the participating facilities . RESULTS: A total of 158 BSIs occurred during 142,525 dialysis sessions within a 12-month study period . Of the BSIs, 15.2% occurred in patients with fistula or graft access and 84.8% in patients with central venous catheter access (P < .001) . Rates per 100 patient-years in centers ranged from 0 to 30.8, with a mean of 16.6 . Rates per 1,000 dialysis sessions ranged from 0 to 2.1, with a mean of 1.1 . Coagulase-negative staphylococci and Staphylococcus aureus (including methicillin-resistant S . aureus) accounted for 61% and Klebsiella or Enterobacter species for 14.6% of infections . Of the patients, 63.3% received vancomycin, 24.7% received cefazolin, and 41.7% received aminoglycosides . Rates declined in the second 6 months of the study from 1.4 to 0.8 infections per 1,000 dialysis sessions (P < .001) . CONCLUSIONS: Primary BSI rates varied widely among participating centers and declined during the study period . BSIs were strongly associated with central venous catheter access . Further studies are needed to determine the reasons for variance in rates between centers and among various types of hemodialysis access. Zhonghua Yi Xue Za Zhi, 2002 Oct 10, 82(19), 1355 - 8 {The expression of AmpC and extended-spectrum beta-lactamases among clinical isolates of enterobacter cloacae and its impact on antibiotics susceptibility}; She D et al.; OBJECTIVE: To investigate the expression of AmpC beta-lactamases and ESBL among clinical isolates of E . cloacae and its impact on antibiotic susceptibility . METHODS: Antibiotic susceptibility was determined by standard agar dilution procedures . beta-lactamases of the isolates with decreased susceptibilities to ceftazidime, cefotaxime, ceftriaxon or aztreonam were investigated by three-dimensional extract tests, isoelectric focusing overlay technique, conjugation experiments and PCR . RESULTS: Among 106 E . cloacae isolates, 16.0% produced only high-level AmpC beta-lactamases, 10.4% produced only ESBL, 13.2% produced both high-level AmpC beta-lactamases and ESBL . 18 isolates (17.0%) carried CTX-M-type ESBL and 7 isolates (6.6%) carried SHV-type ESBL . All carbapenems showed high activity against E . cloacae strains (MIC90 <or= 2 micro g/ml) . More than 70% of the isolates producing only high-level AmpC beta-lactamases were susceptible to cefepime, amikacin, gentamicin or ciprofloxacin . More than 60% of the isolates producing only ESBL were susceptible to piperacillin/tazobactam, cefoperazone/sulbactam, ciprofloxacin or amikacin . The susceptible rates of the isolates producing both high-level AmpC beta-lactamases and ESBL to tested antimicrobial agents other than carbapenems were all lower than 25% . CONCLUSION: CTX-M-type ESBL was prevalent among clinical isolates of E . cloacae . Resistance to expanded-spectrum cephalosporins in E . cloacae was mediated not only by AmpC beta-lactamases but also by ESBL . Expression of ESBL in high-level AmpC beta-lactamases producing strains resulted in a significant rise in resistance level. Int J Antimicrob Agents, 2003 Jan, 21(1), 1 - 7 Sustained activity and spectrum of selected extended-spectrum beta-lactams (carbapenems and cefepime) against Enterobacter spp . and ESBL-producing Klebsiella spp.: report from the SENTRY antimicrobial surveillance program (USA, 1997-2000); Jones RN et al.; Enterobacter spp . and Klebsiella spp . are important clinical pathogens that frequently exhibit resistance to third-generation cephalosporins . In Enterobacter spp . strains, resistance is usually due to derepression of the Amp C locus, whereas plasmid-encoded extended-spectrum beta-lactamases (ESBLs) are primarily responsible for resistance in Klebsiella spp . Here we report the results from the SENTRY Antimicrobial Surveillance Program concerning the rates and trends of resistance to extended-spectrum beta-lactams and other antimicrobial agents in Enterobacter spp . and Klebsiella spp . isolated between 1997 and 2000 in participating hospitals in the United States . Among Enterobacter spp., resistance (MIC>or=32 mg/l) to aztreonam, ceftazidime and ceftriaxone ranged from 12.3 to 21.2% over the 4 years, whereas resistance in Klebsiella (MIC>or=2 mg/l) ranged from 5.9 to 6.8% . There was no trend toward increased resistance to these beta-lactam agents over the monitored period . Carbapenems (imipenem, meropenem) and cefepime had excellent activity against both ceftazidime-susceptible and -resistant Enterobacter spp . and Klebsiella spp . (>99% susceptible), although the minimum inhibitory concentration values of cefepime were higher in ceftazidime-resistant isolates compared with ceftazidime-susceptible isolates . Co-resistance to other antimicrobial agents was common in both tested genus groups. Biosci Biotechnol Biochem, 2002 Nov, 66(11), 2474 - 8 Characterization of five phyllosphere bacteria isolated from Rosa rugosa leaves, and their phenotypic and metabolic properties; Hashidoko Y et al.; Five gram-negative bacteria, all of which were Enterobacteriaceae, were isolated from the phyllosphere of green or senescing leaves of Rosa rugosa, and their phenotypic and physiological characteristics were examined . Partial 16S rDNA sequences led to identification of these isolates as Pantoea agglomerans, Klebsiella terrigena, Erwinia rhapontici, and two strains of Rahnella aquatilis . Interestingly, these phyllosphere bacteria had certain phenotypic and physiological convergences, while they showed their own metabolic properties toward phenolic compounds of plant origin . In particular, the two Ra . aquatilis isolates from the green leaves had a substrate-inducible gallate decarboxylase activity in the resting cells that had been cultured in 1 mM gallic acid- or protocatechuic acid-containing medium . The other three isolates from the senescing leaves did not have this enzyme activity . Simple phenolics that the Ra . aquatilis decarboxylatively produced from benzoic acid derivatives had better antimicrobial activities than those of the substrates. Am J Epidemiol, 2003 Jan 1, 157(1), 40 - 7 Risk factors for resistance to antimicrobial agents among nursing home residents; Loeb MB et al.; The authors prospectively collected data on exposure to antimicrobial agents and susceptibility patterns among all clinical isolates of bacteria taken from 9,156 residents of 50 nursing homes in Canada and the United States in 1998-1999 . Exposure to antimicrobial agents was measured during the 10 weeks prior to detection of targeted resistant bacteria in residents and compared with antibiotic exposure during a 10-week interval in individuals with sensitive organisms . These main effects were adjusted for infection-control and staffing covariates using multiple logistic regression modeling . Increased staffing of nursing homes with registered nurses (adjusted odds ratio (OR) = 0.79 (95% confidence interval (CI): 0.72, 0.87) per registered nurse per 100 resident-days) and use of antibacterial soap (adjusted OR = 0.40, 95% CI: 0.18, 0.90) were associated with reduced risk of methicillin-resistant Staphylococcus aureus in nursing home residents . An increase in the number of hand-washing sinks per 100 residents was shown to reduce the risk of trimethoprim-sulfamethoxazole (TMP/SMX)-resistant Enterobacteriaceae (adjusted OR = 0.94, 95% CI: 0.90, 0.98) . Exposure to TMP-SMX and exposure to fluoroquinolones were significant risk factors for isolation