Salmonella

Vet Microbiol, 1997 Sep, 57(2-3), 171 - 80
Radioactive technetium-99m labelling of Salmonella abortusovis for the assessment of bacterial dissemination in sheep by in vivo imaging; Perin F et al.; We report the development and validation of a 99mTc-labelling technique of bacteria, applied to Salmonella abortusovis . The radioactive labelling is obtained using a pre-tinning step of the cells followed by direct incubation of S . abortusovis suspension with 99mTc-pertechnetate . Several procedures with different amounts of stannous tin (SnF2 or SnCl2) were evaluated . The selected method, respectful of bacterial viability, provided a 30% labelling yield . Viability of 99mTc-labelled bacteria was assessed by flow cytometry using rhodamine 123 and was demonstrated to be unchanged, turbidimetric measurements showing only a slight increase in the growth rate for radiolabelled cells . Incubation of 99mTc-labelled S . abortusovis with pronase, saponine and urea demonstrated labelling stability and suggested an intra-cellular localization for 99mTc . A preliminary study was also conducted in sheep to evaluate the value of the imaging of radiolabelled S . abortusovis . Spatial and temporal patterns of their in vivo dissemination in the lymphatic system after a sub-cutaneous injection were compared with control lymphoscintigraphic agents . These imaging data supported the assumption that the radioactivity detected in vivo was proportional to the number of 99mTc-labelled bacteria.

Philos Trans R Soc Lond B Biol Sci, 1997 Sep 29, 352(1359), 1331 - 45
Immunogenetics of leishmanial and mycobacterial infections: the Belem Family Study; Blackwell JM et al.; In the 1970s and 1980s, analysis of recombinant inbred, congenic and recombinant haplotype mouse strains permitted us to effectively 'scan' the murine genome for genes controlling resistance and susceptibility to leishmanial infections . Five major regions of the genome were implicated in the control of infections caused by different Leishmania species which, because they show conserved synteny with regions of the human genome, immediately provides candidate gene regions for human disease susceptibility genes . A common intramacrophage niche for leishmanial and mycobacterial pathogens, and a similar spectrum of immune response and disease phenotypes, also led to the prediction that the same genes/candidate gene regions might be responsible for genetic susceptibility to mycobacterial infections such as leprosy and tuberculosis . Indeed, one of the murine genes (Nramp1) was identified for its role in controlling a range of intramacrophage pathogens including leishmania, salmonella and mycobacterium infections . In recent studies, multicase family data on visceral leishmaniasis and the mycobacterial diseases, tuberculosis and leprosy, have been collected from north-eastern Brazil and analysed to determine the role of these candidate genes/regions in determining disease susceptibility . Complex segregation analysis provides evidence for one or two major genes controlling susceptibility to tuberculosis in this population . Family-based linkage analyses (combined segregation and linkage analysis; sib-pair analysis), which have the power to detect linkage between marker loci in candidate gene regions and the putative disease susceptibility genes over 10-20 centimorgans, and transmission disequilibrium testing, which detects allelic associations over 1 centimorgan (ca . 1 megabase), have been used to examine the role of four regions in determining disease susceptibility and/or immune response phenotype . Our results demonstrate: (i) the major histocompatibility complex (MHC: H-2 in mouse, HLA in man: mouse chromosome 17/human 6p; candidates class II and class III including TNF alpha/beta genes) shows both linkage to, and allelic association with, leprosy per se, but is only weakly associated with visceral leishmaniasis and shows neither linkage to nor allelic association with tuberculosis; (ii) no evidence for linkage between NRAMP1, the positionally cloned candidate for the murine macrophage resistance gene Ity/Lsh/Bcg (mouse chromosome 1/human 2q35), and susceptibility to tuberculosis or visceral leishmaniasis could be demonstrated in this Brazilian population; (iii) the region of human chromosome 17q (candidates NOS2A, SCYA2-5) homologous with distal mouse chromosome 11, originally identified as carrying the Scl1 gene controlling healing versus nonhealing responses to Leishmania major, is linked to tuberculosis susceptibility; and (iv) the 'T helper 2' cytokine gene cluster (proximal murine chromosome 11/human 5q; candidates IL4, IL5, IL9, IRF1, CD14) controlling later phases of murine L . major infection, is not linked to human disease susceptibility for any of the three infections, but shows linkage to and highly significant allelic association with ability to mount an immune response to mycobacterial antigens . These studies demonstrate that the 'mouse-to-man' strategy, refined by our knowledge of the human immune response to infection, can lead to the identification of important candidate gene regions in man.

Microbiology, 1997 Oct, 143 ( Pt 10), 3201 - 7
Peptides 14VIDLL18 and 96FEAAAL101 defined as epitopes of antibodies raised against amino acid sequences of enterotoxigenic Escherichia coli colonization factor antigen I fused to Salmonella flagellin; Luna MG et al.; Antibodies raised against four hybrid Salmonella flagellins carrying amino acid sequences derived from the fimbrial subunit of the colonization factor I antigen (CFA/I) of enterotoxigenic Escherichia coli (ETEC), i.e . hybrid flagellins Fla I (aa 1-15), Fla II (aa 11-25), Fla III (aa 32-45) and Fla IV (aa 88-102), were not able to inhibit the in vitro binding of CFA/I-expressing ETEC bacteria to enterocyte-like Caco-2 cells . However, one of the hybrid flagellins (Fla II) was recognized by a previously described anti-CFA/I subunit mAb (S-CFA/I 17:8) which was able to block adhesion of CFA/I-expressing bacteria to Caco-2 cells and to bind to the amino acid sequences 15IDLLQ19 of the CFA/I fimbrial subunit . Pepscan analysis of antibodies raised against the hybrid flagellins Fla II and Fla IV showed that they were specific for the sequences 14VIDLL18 and 96FEAAAL101, respectively, of the CFA/I fimbrial subunit . Thus, the discrepancy in the abilities of the anti-Fla II serum and the mAb S-CFA/I 17:8 to block binding might be ascribed to their slightly different fine specificity for epitopes.

Zentralbl Hyg Umweltmed, 1996 Nov, 199(1), 84 - 90
An evaluation of certain Salmonella detection methods in surface water; Bernagozzi M et al.; Two different procedures were employed for detecting Salmonella spp . in environmental water samples: a rapid method (enrichment in Salmosyst Broth and plating in Rambach Agar-Merck) and a longer assay (pre-enrichment in Buffered Peptone Water, enrichment in Selenite-Cistyne Broth and plating in Brilliant Green Agar-Difco) . The efficiency of microbiological tests was measured by the following criteria: recovery, sensitivity and specificity . The results analysed by the Kendall concordance coefficients demonstrated that the rapid method appeared more effective even if poorly specific.

Infect Immun, 1997 Nov, 65(11), 4624 - 33
Salmonellae activate tumor necrosis factor alpha production in a human promonocytic cell line via a released polypeptide; Ciacci-Woolwine F et al.; Invasive strains of Salmonella spp . cause both systemic and localized infections in humans . The ability to resist infection and some aspects of the tissue pathology associated with the presence of Salmonella in the gastrointestinal tract have been shown to be mediated in part by the induction of tumor necrosis factor alpha (TNF-alpha), a proinflammatory cytokine produced by activated macrophages and lymphocytes . Recent reports indicate that TNF-alpha is involved in the induction of human immunodeficiency virus replication by Salmonella in the latently infected human promonocytic cell line U1 . In the present study, we investigated the effects of Salmonella on TNF-alpha production in U1 cells and a related cell line, U38 . Unlike Escherichia coli or Yersinia enterocolitica, salmonellae rapidly induce TNF-alpha expression in these cells through a released factor(s) . Time course experiments show that the kinetics of TNF-alpha production by U38 cells stimulated with Salmonella conditioned medium closely resemble those observed in response to live Salmonella . The observation that TNF-alpha levels are elevated by 60 min after exposure to either bacteria or their conditioned medium suggests that the soluble inducer is continuously released or shed by the bacteria and that the signal acts rapidly to increase TNF-alpha production . Furthermore, the ability to produce the TNF-alpha inducer is shared by at least four Salmonella serotypes and does not correlate with the abilities to invade and to survive within phagocytes . Treatment of active conditioned medium with trypsin, but not low pH, high temperature, or urea, significantly inhibits its TNF-alpha-inducing effect on U38 cells, a finding which points to a polypeptide product of Salmonella as the mediator of TNF-alpha production . Gel filtration chromatography of Salmonella conditioned medium reveals two peaks of activity, consistent with molecular masses of approximately 150 and 110 kDa.

J Bacteriol, 1997 Nov, 179(21), 6551 - 9
Evolutionary genetics of the isocitrate dehydrogenase gene (icd) in Escherichia coli and Salmonella enterica; Wang FS et al.; Sequences of the icd gene, encoding isocitrate dehydrogenase (IDH), were obtained for 33 strains representing the major phylogenetic lineages of Escherichia coli and Salmonella enterica . Evolutionary relationships of the strains based on variation in icd are generally similar to those previously obtained for several other housekeeping and for invasion genes, but the sequences of S . enterica subspecies V strains are unusual in being almost intermediate between those of the other S . enterica subspecies and E . coli . For S . enterica, the ratio of synonymous (silent) to nonsynonymous (replacement) nucleotide substitutions between pairs of strains was larger than comparable values for 12 other housekeeping and invasion genes, reflecting unusually strong purifying selection against amino acid replacement in the IDH enzyme . All amino acids involved in the catalytic activity and conformational changes of IDH are strictly conserved within and between species . In E . coli, the level of variation at the 3' end of the gene is elevated by the presence in some strains of a 165-bp replacement sequence supplied by the integration of either lambdoid phage 21 or defective prophage element e14 . The 72 members of the E . coli Reference Collection (ECOR) and five additional E . coli strains were surveyed for the presence of phage 21 (as prophage) by PCR amplification of a phage 21-specific fragment in and adjacent to the host icd, and the sequence of the phage 21 segment extending from the 3' end of icd through the integrase gene (int) was determined in nine strains of E . coli . Phage 21 was found in 39% of E . coli strains, and its distribution among the ECOR strains is nonrandom . In two ECOR strains, the phage 21 int gene is interrupted by a 1,313-bp insertion element that has 99.3% nucleotide sequence identity with IS3411 of E . coli . The phylogenetic relationships of phage 21 strains derived from sequences of two different genomic regions were strongly incongruent, providing evidence of frequent recombination.

Lett Appl Microbiol, 1997 Oct, 25(4), 246 - 8
Use of antibody-coated cellulose sponges for enhanced isolation of salmonella; Davies RH et al.; One thousand, four hundred and fifty-one naturally contaminated samples from pig, poultry and cattle farms, poultry hatcheries and animal feed mills were examined in a trial in which transfer of small portions of cellulose sponge coated with salmonella somatic polyvalent antiserum was compared with transfer of standard liquid inocula from pre-enrichment to selective enrichment culture . Salmonella was found in 281 (19.4%) of the samples using the standard method, compared with 385 (26.5%) using the sponge method . It was therefore concluded that antibody-coated cellulose sponges could be a simple means of increasing the recovery of salmonellas from pre-enrichment broths and thereby enhancing the test sensitivity.

J Appl Microbiol, 1997 Oct, 83(4), 445 - 55
The use of an automated growth analyser to measure recovery times of single heat-injured Salmonella cells; Stephens PJ et al.; A new approach to the study of recovery times of single heat-injured Salmonella cells is described . It comprises the generation of a standard heat-injured culture, serial dilution of this culture to near extinction, inoculation of the serial dilutions across many microtitre plates and measurement of the subsequent recovery and growth using an automated turbidometric analyser . Lag times for individual cells were estimated from turbidity data using a model that accurately extrapolated the growth curve back to the starting inoculum level . Lag times were compared using a number of different commercially available pre-enrichment media . The most typical result was a very broad distribution of lag times at the single cell inoculum level, with many values in excess of 20 h . Even at an inoculum level 10-fold higher, lag times for some injured cells were estimated to be > 10 h . More significantly, it was found that some media recovered more injured cells than others and vice versa . Between the worst and best media there were as many as 3 log10 cycles difference in the number of cells recoverable . No trends were apparent linking choice of medium with performance . The implications of these findings, in relation to traditional and rapid methodology, are discussed.

J Appl Microbiol, 1997 Oct, 83(4), 438 - 44
Immersion heat treatments for inactivation of Salmonella enteritidis with intact eggs; Schuman JD et al.; The effects of water-bath immersion heat treatments on the inactivation of Salmonella enteritidis within intact shell eggs were evaluated . Six pooled strains of Salm . enteritidis (ca 3 x 10(8) cfu, inoculated near the centre of the yolk) were completely inactivated within 50-57.5 min at a bath temperature of 58 degrees C and within 65-75 min at 57 degrees C (an 8.4 to 8.5-D process per egg) . Following the initial 24 to 35-min come-up period, semilogarithmic survivor curves obtained at 58 and 57 degrees C yielded apparent decimal reduction times (D-values) of 4.5 and 6.0 min, respectively . Haugh unit values increased during heating, while yolk index and albumen pH values were unaffected . Albumen clarity and functionality were affected by the thermal treatments; therefore, extended whip times would be required for meringue preparation using immersion-heated egg whites . Immersion-heated shell eggs could provide Salmonella-free ingredients for the preparation of a variety of minimally-cooked foods of interest to consumers and foodservice operators.

J Appl Microbiol, 1997 Oct, 83(4), 407 - 12
Determination of the influence of organic acids and nisin on shelf-life and microbiological safety aspects of fresh pork sausage; Scannell AG et al.; The effect of replacing sulphur dioxide with organic acids and nisin to reduce the microbial counts in fresh pork sausage was examined . The potential of sodium citrate or sodium lactate, used singly or in combination with nisin, was also assessed in sausage inoculated with Staphylococcus aureus MMPR 3 and Salmonella kentucky AT 1 . The results indicate that a combination of sodium lactate and nisin wa particularly effective in reducing total bacterial counts in this food product . It also appears that this combination provides an increased protection against common pathogenic contaminants of fresh pork sausage, i.e . Staph . aureus and Salmonella species.

Acta Paediatr, 1997 Oct, 86(10), 1056 - 8
Salmonella meningitis: clinical experience of third-generation cephalosporins; Huang LT et al.; Fifteen paediatric patients with Salmonella meningitis were retrospectively reviewed . Presenting symptoms and signs included fever, vomiting, seizures, poor activity, diarrhoea and bulging anterior fontanelle in most patients . Seven out of eight patients with prolonged fever for > 10 days had neurologic sequelae; therefore, prolonged fever is a significant prognostic factor of a poor outcome (p < 0.005) . All 15 patients had a brain ultrasound or computed tomography in the acute stage and 11 patients had abnormal findings . The 14 surviving patients were treated with a third-generation cephalosporin for at least 3 weeks . Seven patients (47%) made complete recoveries; two of them were treated solely with a third-generation cephalosporin . Only one mortality (6%) occurred and there were no relapses . In conclusion, high frequencies of prolonged fever, neuroimaging abnormalities and neurologic sequelae were seen in patients with Salmonella meningitis treated with third-generation cephalosporins.

J Clin Microbiol, 1997 Nov, 35(11), 2786 - 90
Human salmonellosis associated with exotic pets; Woodward DL et al.; During the period from 1994 to 1996, an increase in the number of laboratory-confirmed cases of human salmonellosis associated with exposure to exotic pets including iguanas, pet turtles, sugar gliders, and hedgehogs was observed in Canada . Pet turtle-associated salmonellosis was recognized as a serious public health problem in the 1960s and 1970s, and in February 1975 legislation banning the importation of turtles into Canada was enacted by Agriculture Canada . Reptile-associated salmonellosis is once again being recognized as a resurgent disease . From 1993 to 1995, there were more than 20,000 laboratory-confirmed human cases of salmonellosis in Canada . The major source of Salmonella infection is food; however, an estimated 3 to 5% of all cases of salmonellosis in humans are associated with exposure to exotic pets . Among the isolates from these patients with salmonellosis, a variety of Salmonella serotypes were also associated with exotic pets and included the following: S . java, S . stanley, S . poona, S . jangwani, S . tilene, S . litchfield, S . manhattan, S . pomona, S . miami, S . rubislaw, S . marina subsp . IV, and S . wassenaar subsp . IV.

Am J Trop Med Hyg, 1997 Oct, 57(4), 438 - 44
Enteropathogenic bacteria in the La Paz River of Bolivia; Ohno A et al.; Diarrheal diseases often result from ingestion of contaminated water or food . The population of La Paz, Bolivia is directly or indirectly exposed to the sewage-contaminated La Paz River . We conducted a bacteriologic survey of the La Paz River to quantify the level of bacterial contamination, with particular reference to enteropathogens . A total bacterial count exceeding 10(6) colony-forming units (CFU)/ml, including lactose fermenting and nonfermenting, gram-negative bacilli of approximately 10(5) CFU/ml, respectively, were detected in river water samples collected near two densely populated areas . A total bacterial count of 10(5) CFU/ml was also detected at the most downstream area of the river near a sparsely populated area . At four sampling locations, several enteropathogens were detected, including five enterotoxigenic Escherichia coli (ETEC) (serotype O6, O15, and O159), two enteropathogenic E . coli (EPEC) (serotype O44), two enteroinvasive E . coli (EIEC) (serotype O29), and three Salmonella O4 group isolates . The heat-labile enterotoxin gene and the invasive toxin gene were detected in all ETEC and EIEC isolates by polymerase chain reaction analysis . Nine isolates of E . coli were found by the agar dilution method to be susceptible to ampicillin, kanamycin, nalidixic acid, tetracycline, and chloramphenicol, and ampicillin resistance was found in only two isolates of EIEC 7-4 (serotype O29) and EPEC 7-5 (serotype O44) . Ampicillin resistance was coded on plasmids and transferred conjugatively to E . coli chi1037 at a frequency of 10(-5) CFU/donor by the broth mating method . Strains of Aeromonas caviae, which can cause diarrheal disease in infants, were detected in vegetables grown in fields irrigated by water from the La Paz River . The survival of nine isolates of E . coli in filtered river water was compared with that of laboratory strains (E . coli chi1037, W3110, and ATCC29577) . The survival time of seven isolates, excluding two ampicillin-resistant isolates, was markedly longer than that of the laboratory strains . Our results show a high bacterial contamination of the La Paz river and suggest that such levels may contribute to the high incidence of diarrheal disease in the city of La Paz.

J Med Assoc Thai, 1997 Sep, 80 Suppl 1, S149 - 54
Immunopharmacological activity of polysaccharide from the pericarb of mangosteen garcinia: phagocytic intracellular killing activities; Chanarat P et al.; Polysaccharides from the pericarbs of mangosteen, Garcinia mangostana Linn., was obtained by treating the dried ground pericarbs with hot water followed by ethanol precipitation (M fraction) . The extract was fractionated by anion exchange chromatography on a DEAE-cellulose column as MDE1-5 fractions . The fractions of MDE3 and MDE4 composed of mainly D-galacturonic acid and a small amount of neutral sugar (L-arabinose as the major one and L-rhamnose and D-galactose as the minor ones) were studied for immunopharmacological activities by phagocytic test to intracellular bacteria (Salmonella enteritidis) and nitroblue tetrazolium (NBT) and superoxide generation tests . The results showed that the number of S . enteritidis in cultured monocyte with extract of pericarb of mangosteen (MDE3) was killed . Activating score (mean +/- SD) of NBT test of 100 polymorphonuclear phagocytic cells were 145 +/- 78, 338 +/- 58, 222 +/- 73, 209 +/- 77, 211 +/- 63, 372 +/- 19, 369 +/- 20, 355 +/- 34 in normal saline control, phorbol myristate acetate (PMA), MDE3, MDE4, indomethacin (I), PMA + MDE3, PMA + MDE4 and PMA + I, respectively . Superoxide generation test was also done by color reduction of cytochrome c . Both MDE3 and MDE4 stimulate superoxide production . The number of S . enteritidis in cultured monocyte with extract of pericarb of mangosteen was killed . This paper suggests that polysaccharides in the extract can stimulate phagocytic cells and kill intracellular bacteria (S . enteritidis).

West Afr J Med, 1997 Jul-Sep, 16(3), 195 - 8
Superficial Salmonella abscesses in two siblings with sickle cell diseases; Mansoury B et al.; Salmonella infection in sickle cell disease patients is generally well-known but presentation as superficial abscess is relatively uncommon . Two sisters aged 4 1/2 and 6 years presented with superficial subcutaneous abscesses that were caused by the same strain of Salmonella enteriditis group C . Despite in vitro susceptibility with a MIC of 0.03 microgram/ml and an adequate dosage of ciprofloxacin there was a relapse with widespread dissemination of the same organism in the younger sister who subsequently developed multiple osteolytic infections . Change of treatment to chloramphenicol produced a cure in both patients.

Am J Vet Res, 1997 Oct, 58(10), 1125 - 31
Induction of gross and microscopic lesions of porcine proliferative enteritis by Lawsonia intracellularis; Joens LA et al.; OBJECTIVE: To evaluate experimental induction of porcine proliferative enteritis (PPE), using cell cultured Lawsonia intracellularis (ileal symbiont intracellularis), and to determine whether dexamethasone administration or age of the host or both affects susceptibility to L intracellularis infection . ANIMALS: Thirty-two 3- or 7-week-old pigs . PROCEDURES: Lawsonia intracellularis was extracted from tissue with lesions of PPE and was subcultured in a continuous Henle 407 cell line at 37 C under an atmosphere of 5% CO2 . Three- or 7-week-old pigs were inoculated orally with 100 ml of a 10-day-old cell culture preparation of the bacterium or infective intestinal homogenates . Control pigs were inoculated with uninfected Henle cells . Pigs were observed daily for clinical signs of infection and necropsied at death or at termination of the study . Lesions in the small and large intestines were recorded . RESULTS: Diarrhea was observed in pigs 4 to 7 days after inoculation with the pure culture agent or homogenates and lasted throughout the study period . Histologic lesions consistent with PPE were detected in pigs inoculated with pure culture . Intestinal lesions were absent in control pigs inoculated with uninfected Henle cells . Differences in lesions were not significant between treatment groups that varied in age or were receiving dexamethasone . Tissue specimens from pigs at necropsy were culture negative for Salmonella spp and Serpulina hyodysenteriae . CONCLUSION AND CLINICAL RELEVANCE: Gross and microscopic lesions typical of acute PPE were induced in pigs by use of a cell culture agent . Age differences and the stress induced by administration of dexamethasone had no effect on development of intestinal lesions.

Am J Pathol, 1997 Oct, 151(4), 1163 - 9
Dephosphorylation of endotoxin by alkaline phosphatase in vivo; Poelstra K et al.; Natural substrates for alkaline phosphatase (AP) are at present not identified despite extensive investigations . Difficulties in imagining a possible physiological function involve its extremely high pH optimum for the usual exogenous substrates and its localization as an ecto-enzyme . As endotoxin is a substance that contains phosphate groups and is usually present in the extracellular space, we studied whether AP is able to dephosphorylate this bacterial product at physiological pH levels . We tested this in intestinal cryostat sections using histochemical methods with endotoxin from Escherichia coli and Salmonella minnesota R595 as substrate . Results show that dephosphorylation of both preparations occurs at pH 7.5 by AP activity . As phosphate residues in the lipid A moiety determine the toxicity of the molecule, we examined the effect of the AP inhibitor levamisole in vivo using a septicemia model in the rat . The results show that inhibition of endogenous AP by levamisole significantly reduces survival of rats intraperitoneally injected with E . coli bacteria, whereas this drug does not influence survival of rats receiving a sublethal dose of the gram-positive bacteria Staphylococcus aureus . In view of the endotoxin-dephosphorylating properties of AP demonstrated in vitro, we propose a crucial role for this enzyme in host defense . The effects of levamisole during gram-negative bacterial infections and the localization of AP as an ecto-enzyme in most organs as well as the induction of enzyme activity during inflammatory reactions and cholestasis is in accordance with such a protective role.

Prev Med, 1997 Sep-Oct, 26(5 Pt 1), 599 - 602
Review--animal waste used as livestock feed: dangers to human health; Haapapuro ER et al.; Foodborne illness remains a common and serious problem, despite efforts to improve slaughterhouse inspection and food preparation practices . A potential contributor to this problem that has heretofore escaped serious public health scrutiny is the feeding of animal excrement to livestock, a common practice in some parts of the United States . In 1994, 18% of poultry producers in Arkansas collectively fed more than 1,000 tons of poultry litter to cattle, and the procedure is also common in some other geographic areas as a means of eliminating a portion of the 1.6 million tons of livestock wastes produced in the United States annually . While heat processing reliably kills bacterial pathogens, its use is limited by expense and other factors . Deep-stacking and ensiling are commonly used by farmers to process animal wastes, but the maximal temperatures achieved in stacked poultry litter are typically in the range of 43 to 60 degrees C (110 to 140 degrees F), below the inactivation temperatures of pathogenic salmonella and Escherichia coli species, and far below the USDA's recommended cooking temperatures of 71 to 77 degrees C (160 to 170 degrees F) for potentially manure-tainted meat products . In addition to the spread of potential pathogens, using animal wastes as feed presents the possibility that antibiotic-resistant bacteria may spread from one animal to another and that antibiotics or other chemicals may be passed between animals . Few research reports have addressed the safety of this practice, and those studies that have been published have generally been in controlled and artificial environments, rather than in on-farm conditions . Further microbiological studies are recommended to assess the extent of risk.

Arzneimittelforschung, 1997 Sep, 47(9), 1052 - 5
Pharmacodynamic parameters of ofloxacin, tobramycin and ceftriaxone and their effect on the biological properties of salmonellae; Majtan V et al.; The postantibiotic effect and postantibiotic sub-MIC effect of ofloxacin (CAS 82419-36-1), tobramycin (CAS 32986-56-4) and ceftriaxone (CAS 73384-59-5) on two salmonella serotypes (S . typhimurium and S . enteritidis) were studied . The influence of postantibiotic effect and postantibiotic sub-MIC effect of the antibiotics on prophage induction of the lysogenic S . typhimurium strain and on Congo red binding by both serovars as indicator of their invasive ability was examined . The postantibiotic effect was induced by exposure of the bacteria to the 2x and 4x MIC concentrations of antibiotics studied for 0.5 h . The postantibiotic effects were different; ceftriaxone induced the longest postantibiotic effect against S . enteritidis, and the 4x MIC of tobramycin induced the longest postantibiotic effect against S . typhimurium . The postantibiotic sub-MIC effects lasted longer and in the case of subinhibitory concentrations of tobramycin on S . typhimurium and ceftriaxone on S . enteritidis did not allow any regrowth . The results showed that the postantibiotic effect and postantibiotic sub-MIC effect of ofloxacin induced a prophage of a lysogenic S . typhimurium strain, and the postantibiotic sub-MIC effects of tobramycin influenced Congo red binding by S . enteritidis cells.

Clin Exp Immunol, 1997 Sep, 109(3), 431 - 8
Antagonistic effects of IL-4 and interferon-gamma (IFN-gamma) on inducible nitric oxide synthase expression in bovine macrophages exposed to gram-positive bacteria; Jungi TW et al.; Cytokine-mediated modulation of nitric oxide (NO) production by bacteria-stimulated bovine macrophages was studied . When Salmonella dublin, as a prototypic gram-negative organism, was used, NO generation was barely enhanced by recombinant bovine and ovine IFN-gamma, but was suppressed by IL-4 . Salmonella dublin-induced NO generation was not influenced by a panel of nine other cytokines . The panel included IL-1, tumour necrosis factor (TNF) and IFN-alpha, which are active in a similar mouse macrophage model . The tested cytokines were either homologous or known to interact with bovine cytokine receptors . Recombinant bovine and ovine IFN-gamma were the only cytokines which strongly enhanced NO synthesis by macrophages exposed to the gram-positive organism, Listeria monocytogenes . Listeria-induced NO generation was strongly suppressed by recombinant human and bovine IL-4, but not by IL-10 and transforming-growth-factor-beta . Thus, two cytokines characterizing a Th1 and a Th2 response up- and down-regulate, respectively, bacteria-induced NO generation in bovine macrophages, whereas nine other cytokines had little activity in this regard . This modulation was reflected in changes in the steady state levels of mRNA coding for inducible nitric oxide synthase . Combinations of IFN-gamma and IL-4 suggested that the relative proportion of these cytokines determined whether bacteria-induced NO generation was up- or down-regulated . At saturating IL-4 concentrations, stimulation of bacteria-induced NO generation in macrophages by T cell supernatants was solely dependent on IFN-gamma . This was shown by antibody neutralization experiments and by a close correlation between the capacity of supernatants to stimulate NO generation and the IFN-gamma content, as determined by immunoassay.

Pediatr Cardiol, 1997 Nov-Dec, 18(6), 443 - 4
Right-sided endocarditis due to Salmonella typhi; du Plessis JP et al.; A case of right-sided endocarditis due to Salmonella typhi is described involving a native tricuspid valve in a child who was human immunodeficiency virus negative with no evidence of intravenous drug addiction . The patient had classic features of typhoid and tricuspid regurgitation without clinical evidence of bacterial endocarditis . Transthoracic echocardiography confirmed the tricuspid regurgitation . However, transesophageal echocardiography was necessary to demonstrate the vegetations affecting the tricuspid valve leaflets that made possible the diagnosis of endocarditis . The infection was cured with intravenous ceftriaxone and oral amoxicillin.

Nature, 1997 Oct 16, 389(6652), 742 - 5
Lipopolysaccharide-binding protein is required to combat a murine gram-negative bacterial infection; Jack RS et al.; An invading pathogen must be held in check by the innate immune system until a specific immune response can be mounted . In the case of Gram-negative bacteria, the principal stimulator of the innate immune system is lipopolysaccharide (LPS), a component of the bacterial outer membrane . In vitro, LPS is bound by lipopolysaccharide-binding protein (LBP) and transferred to CD14--the LPS receptor on the macrophage surface--or to high-density lipoprotein (HDL) particles . Transfer to CD14 triggers an inflammatory response which is crucial for keeping an infection under control . Here we investigate how LBP functions in vivo by using LBP-deficient mice . Surprisingly, we find that LBP is not required in vivo for the clearance of LPS from the circulation, but is essential for the rapid induction of an inflammatory response by small amounts of LPS or Gram-negative bacteria and for survival of an intraperitoneal Salmonella infection.

Cancer Res, 1997 Oct 15, 57(20), 4537 - 44
Tumor-targeted Salmonella as a novel anticancer vector; Pawelek JM et al.; There has been little investigation of bacteria as gene delivery vectors . Here, we demonstrate that genetically engineered Salmonella have many of the desirable properties of a delivery vector, including targeting of multiple tumors from a distant inoculation site, selective replication within tumors, tumor retardation, and the ability to express effector genes, such as the herpes simplex virus thymidine kinase (HSV TK) . When wild-type Salmonella were introduced into melanoma-bearing mice, the bacteria were found within the tumor at levels exceeding 10(9) per g, although as pathogens, they caused the death of the mice . However, when attenuated, hyperinvasive auxotrophic mutants were used, the tumor-targeting and amplification phenomena were retained, whereas their pathogenicity was limited . With such attenuated strains, the tumor:liver ratios ranged between 250:1 and 9000:1 . When these auxotrophs were inoculated i.p . into C57B6 mice bearing B16F10 melanomas, they suppressed tumor growth and prolonged average survival to as much as twice that of untreated mice . A plasmid containing the HSV TK gene with a beta-lactamase secretion signal was constructed that, when expressed, resulted in translocation to the periplasm and phosphorylation of the prodrug ganciclovir . Melanoma-bearing animals inoculated with HSV TK-expressing Salmonella showed ganciclovir-mediated, dose-dependent suppression of tumor growth and prolonged survival in addition to that seen with bacteria alone . The results demonstrate that attenuated Salmonella would be useful both for inherent antitumor activity and delivery of therapeutic proteins to cancer cells in vivo.

Arthritis Rheum, 1997 Oct, 40(10), 1788 - 97
Crucial role of interleukin-10/interleukin-12 balance in the regulation of the type 2 T helper cytokine response in reactive arthritis; Yin Z et al.; OBJECTIVE: To investigate whether a predominant type 1 T helper (Th1) or Th2 cytokine pattern is present in the joints of patients with reactive arthritis (ReA), and whether the cytokine pattern can be modulated by cytokines or anticytokines . METHODS: Eleven patients with ReA following infection with either Chlamydia trachomatis, Yersinia enterocolitica, or Salmonella enteritidis were investigated for the presence of Th1/Th2 cytokines in the joints . Release of the bacteria-specific cytokines interferon-gamma (IFN gamma), tumor necrosis factor alpha (TNF alpha), interleukin-10 (IL-10), and IL-4 was measured in synovial fluid mononuclear cells (SFMC) using enzyme-linked immunosorbent assay and polymerase chain reaction . In the synovial membrane, secretion of IFN gamma and IL-4 was determined by immunohistologic analysis . Cytokine regulation was studied by adding cytokines and anticytokines to the cultures . RESULTS: Upon stimulation with specific bacteria, SFMC secreted low amounts of IFN gamma and TNF alpha, but high amounts of IL-10 . IL-10 was responsible for the suppression of IFN gamma and TNF alpha, as judged by the effect of adding either anti-IL-10 antibodies or exogenous IL-10 to these cultures . The addition of neutralizing anti-IL-12 to the cultures completely abolished the effects of anti-IL-10, suggesting that inhibition of the Th1-like cytokines by IL-10 is mediated through suppression of IL-12 synthesis . Exogenous IL-12 clearly enhanced IFN gamma and TNF alpha secretion . In the synovial membrane, a higher number of cells were positive for the Th2 cytokine IL-4, compared with the amount of IFN gamma-secreting cells . CONCLUSION: These data indicate that a Th2 cytokine pattern predominates in the joints of patients with ReA . Since Th1 cytokines are necessary for the elimination of ReA-associated bacteria, Th2 cytokines might contribute to bacterial persistence in the joint . Therefore, the IL-10/IL-12 balance appears to be crucial for regulation of the cytokine pattern in the joints of patients with ReA.

J Biol Chem, 1997 Oct 17, 272(42), 26419 - 24
alpha-KDOase activity in oyster and synthesis of alpha- and beta-4-methylumbelliferyl ketosides of 3-deoxy-D-manno-octulosonic acid; Li YT et al.; Although alpha- and beta-linked 3-deoxy-D-manno-octulosonic acid (KDO) is found in lipopolysaccharides (LPSs) of Gram-negative bacteria, capsular polysaccharides of microorganisms, and plants, very little is known about its degradation . Using both thin-layer chromatography and the periodate-thiobarbituric acid reaction, we found that the hepatopancreas of oyster (Crassostrea virginica) contained an enzyme (alpha-KDOase) capable of releasing alpha-linked KDO from LPSs . To facilitate the studies of alpha-KDOase, we have carried out the synthesis of 4-methylumbelliferyl-alpha-KDO (alpha-KDO-MU) by conjugating the glycosyl chloride of the per-O-acetylated methylester of KDO with methylumbelliferone by the SN2 type reaction and the catalyzed phase-transfer . In both cases, the beta-anomer was obtained as the major product with a yield of about 80%, whereas the yield of alpha-anomer was only about 7% . Attempts to increase the yield of alpha-anomer were not successful . alpha-KDO-MU was used as substrate to follow the purification of alpha-KDOase from oyster hepatopancreas . The pH optimum for oyster alpha-KDOase was determined to be 4.5 using Re-LPS as substrate and 3.0 using alpha-KDO-MU as substrate . The enzyme was found to be stable in the pH range of 3-8 . This enzyme released KDO from different LPSs, including Re-LPS from Escherichia coli and Salmonella minnesota, Rd-LPS from S . minnesota, and de-O-acyl-Re-LPS (Kiang, J., Szu, S . C., Wang, L.X., Tang, M., and Lee, Y . C . (1997) Anal . Biochem . 245, 97-101).

Cancer Res, 1997 Oct 1, 57(19), 4378 - 83
Polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin induce intrachromosomal recombination in vitro and in vivo; Schiestl RH et al.; Polychlorinated aromatic hydrocarbons such as polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) are extremely stable and widely distributed environmental pollutants . These chemicals are animal carcinogens and probable human carcinogens, and TCDD is possibly one of the most potent toxins ever evaluated by the United States Environmental Protection Agency . Polychlorinated aromatic hydrocarbons score negatively in most genotoxicity assays, including the Ames (Salmonella) assay . Although their mechanism of toxicity is not well understood, they induce aryl hydrocarbon (AH) hydroxylases and bind to the AH receptor, which is believed to mediate toxicity . Here, we determine effects of polychlorinated aromatic hydrocarbons in genotoxicity assays that score for DNA deletions by intrachromosomal recombination in vivo and in vitro . In this study, TCDD, Aroclor 1221, and Aroclor 1260 induced deletions in vivo in the mouse embryo; Aroclor 1221 and Aroclor 1260 induced deletions in yeast . We also show that the induced deletion events did not correlate with induction of AH hydroxylase . None of the tested compounds induced CYP1A-associated ethoxyresorufin-O-deethylase activity in mouse embryos or in vitro . These results clearly demonstrate a genotoxic activity of polychlorinated aromatic hydrocarbons in vitro and in vivo, which is independent of induction of cytochrome P450 activity . Because genetic instability and deletions may be mechanistically involved in carcinogenesis, these results may encourage further research to determine whether such genotoxic mechanisms may be useful for cancer risk assessment of polychlorinated aromatic hydrocarbons.

J Rheumatol, 1997 Oct, 24(10), 2047 - 50
Different course of reactive arthritis in two HLA-B27 positive brothers with fatal outcome in one; Yli-Kerttula T et al.; During an outbreak of Yersinia pseudotuberculosis III, one of two HLA-B27 positive brothers developed reactive arthritis (ReA), mild at first, but later severely destructive and ultimately fatal . The reactivation of ReA was possibly triggered by an oral polio vaccine . The cause of death was severe secondary amyloidosis . The other brother was exposed to the same Y . pseudotuberculosis strain but did not develop any disease during or after the outbreak . However, he later developed ReA due to a Salmonella infection, with a benign course.

Vet Rec, 1997 Sep 20, 141(12), 297 - 9
Bacteriological monitoring of Salmonella enteritidis carrier birds after decontamination using enrofloxacin, competitive exclusion and movement of birds; Humbert F et al.; Two hundred and forty, four-week-old laying birds naturally infected with Salmonella enteritidis PT33 (Pasteur Institute phage typing system) were randomly divided twice (before and during the treatments) to obtain four separately housed groups of 60 birds and to study the efficacy of three decontamination treatments: enrofloxacin either with or without the movement of birds to a clean area, and enrofloxacin combined with movement of birds and a competitive exclusion treatment . The control group remained untreated . In each group contamination with S enteritidis was checked bacteriologically, every week from two months before until two months after the treatments began . All the samples taken from all the birds before the treatments began were S enteritidis-positive . After the treatments it was not possible to isolate salmonella either from the environment or from the faeces of the three treated groups . All the birds were humanely sacrificed at 22 weeks of age and samples of liver, spleen, ovaries and caeca were analysed for the presence of salmonella . The results demonstrated that although antibiotic therapy, the movement of birds into a clean house and competitive exclusion, either combined or not, had some efficacy in reducing infection levels, it was not possible to decontaminate all the birds completely.

Gene, 1997 Sep 1, 196(1-2), 145 - 58
A ColE1-type plasmid from Salmonella enteritidis encodes a DNA cytosine methyltransferase; Ibanez M et al.; The multicopy plasmid pFM366 was isolated from a virulent Salmonella enteritidis strain and was found to code for DNA methylase activity (Ibanez and Rotger, 1993) . The present work was aimed at characterizing the genetic organization and functional features of this 5.6 kb plasmid . We found pFM366 almost identical to the plasmid P4 isolated from Shigella sonnei, that encodes the SsoII restriction-modification system (Karyagina et al., 1993), and related to other ColE1-type plasmids . Examination of these plasmids revealed a common organization which suggests they were the result of similar recombinational events . The cytosine methylase of pFM366 is nearly identical to M . SsoII, whereas the gene encoding the restrictase homologous to R . SsoII is truncated and its product is inactive . The expression of the cytosine methylase encoded by pFM366 is strongly affected by deletion of regions located upstream and downstream of its ORF, and is negatively controlled by the rpoS gene in Escherichia coli . The methylase activity encoded by pFM366 induces the SOS response, which could be responsible for the observed delay in the growth of E . coli.

Gastroenterology, 1997 Oct, 113(4), 1214 - 23
Differential and regulated expression of C-X-C, C-C, and C-chemokines by human colon epithelial cells; Yang SK et al.; BACKGROUND & AIMS: Intestinal epithelial cells constitute a barrier between host and external milieu and can play a role in signaling the influx of leukocytes during the acute mucosal inflammatory response . To further explore this role, the regulated expression of twelve C-X-C, C-C, and C-chemokines by human colon epithelial cells was characterized . METHODS: Chemokine production was assessed in HT-29 and Caco-2 human colon epithelial cells that were infected with Salmonella dublin or stimulated with interleukin 1 alpha or tumor necrosis factor alpha and in freshly isolated human colon epithelial cells by quantitative reverse-transcription polymerase chain reaction and enzyme-linked immunosorbent assay . RESULTS: Expression of the neutrophil chemoattractants GRO-alpha, GRO-gamma, and interleukin 8 increased rapidly (2-3 hours) but transiently after infection or proinflammatory agonist stimulator . In contrast, expression of another neutrophil chemoattractant, epithelial cell-derived neutrophil activator 78, was delayed for 6-10 hours, and secretion continued to increase for 24 hours after infection . Among C-C chemokines known to chemoattract different leukocyte populations, monocyte chemotactic peptide 1 was rapidly expressed, whereas RANTES was up-regulated with delayed kinetics . Freshly isolated colon epithelial cells produced an array of chemokines similar to the cell lines, as well as macrophage inflammatory proteins 1 alpha and 1 beta . CONCLUSIONS: These data suggest that regulated chemokine production by epithelial cells results in temporal and spatial mucosal chemokine gradients that are important in both early and later phases of the mucosal inflammatory response.

Southeast Asian J Trop Med Public Health, 1997 Mar, 28(1), 114 - 9
Characteristics of childhood diarrhea associated with enterotoxigenic Escherichia coli in Malaysia; Samuel S et al.; Amongst 107 diarrheal cases studied a bacterial agent was isolated from 71 (66%) cases of which 60 (85%) were due to a single agent and the remaining 11 (15%) were of mixed infections . Enterotoxigenic Escherichia coli (ETEC) was isolated from 65 cases . Other pathogens isolated included Salmonella spp, Shigella spp and rotavirus . There was a higher isolation rate of ETEC from females and rotavirus from males . The infection rate was found to higher for the 0-2 year age group as compared to the 3-5 year age group . Amongst the ETEC isolated the STa 2 toxotype was the predominant type.

Southeast Asian J Trop Med Public Health, 1997 Mar, 28(1), 85 - 90
An institutional outbreak of Salmonella enteritidis in Singapore; Ng DP et al.; A large outbreak of food poisoning occurred in Singapore in March 1995 when a total of 188 inmates in an institution was taken ill . Salmonella enteritidis was isolated from the stool cultures of 35 inmates (16 symptomatic and 19 asymptomatic) . All the isolates were of the serotype profile 0:1, 9, 12 and H:g, m (antigen phase I); all were sensitive to ampicillin, ceftriaxone, chloramphenicol, co-trimoxazole and ciprofloxacin . Plasmid profile analysis and restriction enzyme fragmentation patterns (REFPs), as generated with EcoRI and HindIII, of a 60 kb plasmid obtained from these isolates were all identical, confirming that the outbreak resulted from a single source of infection . Stratified statistical analysis of food-specific attack rates strongly implicated imported canned luncheon pork consumed by the inmates on 26 March 95 as the single most probable cause of the food poisoning {p < 10(6), Mantel-Haenszel weighted odds ratio (OR) = 14.33; 95% confidence interval (CI) = 6.20-33.15} . The median incubation period of this outbreak was 19.3 hours and the median duration of illness was three days . The outbreak was rapidly brought under control through prompt implementation of epidemic control measures which comprised active search for diarrheal cases, rectal swabbing of asymptomatic inmates, isolation of those found to be infected, and maintenance of a high standard of personal, food and environmental hygiene.

Southeast Asian J Trop Med Public Health, 1997 Mar, 28(1), 82 - 4
Pulsed-field gel electrophoresis as an epidemiologic tool in the investigation of laboratory acquired Salmonella typhi infection; Koay AS et al.; Strains of Salmonella typhi implicated in two separate cases of laboratory acquired infection from patients and the medical laboratory technologists who processed the patients' samples were analysed by pulsed-field gel electrophoresis . Although all four isolates were of bacteriophage type E1, PFGE was able to demonstrate that the strains responsible for the two laboratory acquired cases were not genetically related . The PFGE patterns of the isolates from the MLTs were found to be identical to those of the corresponding patients after digestion with restriction enzyme AvrII . This provided genetic as well as epidemiological evidence for the source of the laboratory acquired infections.

Southeast Asian J Trop Med Public Health, 1997 Mar, 28(1), 73 - 81
Construction of specific DNA probe for the detection of Salmonella in food; Pilantanapak A et al.; The Salmonella specific DNA fragment from genomic DNA of S . typhimurium ATCC 23566 was cloned in E . coli and successfully used as a digoxigenin labeled probe for detecting the presence of Salmonella serotypes in both artificially contaminated food and natural contaminated food samples.

FEMS Immunol Med Microbiol, 1997 Sep, 19(1), 95 - 100
Ontogeny of the phagocytic and bactericidal activities of turkey heterophils and their potentiation by Salmonella enteritidis-immune lymphokines; Lowry VK et al.; Heterophils, the functional equivalent to the mammalian neutrophil, are important mediators of natural resistance against invasive pathogens in poultry . Young poultry are susceptible to pathogens, such as Salmonella enteritidis, during the first week post-hatch . No studies have evaluated the ontogeny of heterophil function in turkeys during the first few weeks post-hatch . Previous studies from our laboratory have shown day-old poults were protected against S . enteritidis organ invasion following immunoprophylactic administration of chicken S . enteritidis immune lymphokines . Therefore, the objective in the present study was to characterize the development of phagocytosis and bacterial killing by turkey heterophils during the first 3 weeks of life and to compare the effect of immune lymphokines on the development of heterophil phagocytosis and killing during the first 3 weeks post-hatch . Both functional phagocytosis and killing activities were age-dependent events . During the first 1-7 days post-hatch, little functional activity was demonstrated which apparently is associated with susceptibility . Optimal heterophil phagocytosis and killing activities were reached 14-21 days post-hatch . Administration immune lymphokines significantly potentiated phagocytosis (P < 0.01) and killing (P < 0.001) by turkey heterophils . In fact, immune lymphokine administration to 1-7-day-old poults augmented phagocytosis and killing activities of heterophils equivalent to levels found in functionally mature 14-21-day-old poults . These results demonstrate the ontogeny of the functional activity of the turkey heterophil is an age-related phenomenon, with inefficient phagocytosis and killing during the first week post-hatch . Prophylactic administration of immune lymphokines significantly potentiated the functional activity of the heterophil poults during the first 3 weeks of life . Most importantly the administration of immune lymphokines enhanced the functional activity of heterophils from 1-7-day-old poults to levels comparable to that of an immunologically mature bird.

Am J Physiol, 1997 Sep, 273(3 Pt 2), R1158 - 62
A sublethal dose of LPS to pregnant rats induces TNF-alpha tolerance in their 0-day-old offspring; Goto M et al.; The newborn has high mortality in septic shock . Induction of endotoxin tolerance may prevent endotoxic shock in the newborn . The present study showed that a small dose of Salmonella enteritidis lipopolysaccharide (S . ent . LPS), Rc mutant Escherichia coli lipopolysaccharide (J5 LPS), or tumor necrosis factor-alpha (TNF-alpha) given to pregnant rats on the 19th day of gestation induced endotoxin tolerance in their 0-day-old offspring . S . ent . LPS or J5 LPS injected into pregnant rats increased plasma endotoxin-like activity in dams, although not in their fetuses, and increased plasma TNF-alpha concentration in both dams and their fetuses . The endotoxin-tolerant newborn rats were also resistant to TNF-alpha . In those newborn rats, an LPS injection increased plasma TNF-alpha concentration and liver TNF-alpha mRNA abundance . These experiments showed that the endotoxin tolerance could be due to TNF-alpha tolerance . In conclusion, prenatal treatment of dams with a small dose of S . ent . LPS, J5 LPS, or TNF-alpha was beneficial in preventing endotoxic shock in the newborn.

Infect Immun, 1997 Oct, 65(10), 4236 - 42
HLA-B27 modulates the survival of Salmonella enteritidis in transfected L cells, possibly by impaired nitric oxide production; Virtala M et al.; Reactive arthritis is triggered by certain microbes that cause primary infections mainly on the gastrointestinal or urogenital mucosa . The disease is strongly associated with HLA-B27 . Long persistence of causative microbes or their structures in the body has been thought to have an important role in the pathogenesis of reactive arthritis . This suggests that the elimination of the microbes causing reactive arthritis is ineffective or disturbed in HLA-B27-positive individuals developing this complication . We examined the role of the HLA-B27 antigen in microbe-host interaction in vitro by monitoring the invasion and intracellular survival of Salmonella enteritidis in mouse fibroblasts transfected with HLA-B27, HLA-B7, or beta2-microglobulin only . S . enteritidis invaded into all the three transfectants with the same efficiency . However, at 6 and 10 days after incubation, there were more living intracellular Salmonella organisms in HLA-B27 transfectants than in the other transfected cell lines (P < 0.05), suggesting that the bactericidal effect is impaired in these cells . Impaired NO production in HLA-B27-transfected cells was indicated as a possible mechanism, since the amount of nitrite in the supernatants of the Salmonella-infected HLA-B27-transfected cells was smaller than that in the supernatants of the Salmonella-infected HLA-B7- or beta2-microglobulin-transfected cells (P < 0.001) . The inhibition of NO synthesis by N-monomethyl-L-arginine resulted in impaired elimination of Salmonella also in HLA-B7and beta2-microglobulin-transfected cells . The inverse correlation between intracellular survival of Salmonella and the amount of nitrite detected in culture supernatants supports the hypothesis that the L-arginine-dependent NO pathway plays an important role in the murine fibroblast response against Salmonella . We suggest that a major histocompatibility complex class I antigen, HLA-B27, may contribute to the intracellular persistence of Salmonella by a mechanism which involves the NO pathway.

Infect Immun, 1997 Oct, 65(10), 4094 - 9
Lipopeptides of Borrelia burgdorferi outer surface proteins induce Th1 phenotype development in alphabeta T-cell receptor transgenic mice; Infante-Duarte C et al.; Induction of the appropriate T helper cell (Th) subset is crucial for the resolution of infectious diseases and the prevention of immunopathology . Some pathogens preferentially induce Th1 or Th2 responses . How microorganisms influence Th phenotype development is unknown . We asked if Borrelia burgdorferi, the spirochete which causes Lyme arthritis, can promote a cytokine milieu in which T cells which are not specific for B . burgdorferi are induced to produce proinflammatory cytokines . Using alphabeta T-cell receptor transgenic mice as a source of T cells with a defined specificity other than for B . burgdorferi, we found that B . burgdorferi induced Th1 phenotype development in ovalbumin-specific transgenic T cells . Small synthetic lipopeptides corresponding to the N-terminal sequences of B . burgdorferi outer surface lipoproteins had similar effects . B . burgdorferi and its lipopeptides induced host cells to produce interleukin-12 . When the peptides were used in delipidated form, they did not induce Th1 development . These findings may be of pathogenic importance, since it is currently assumed that a Th2-mediated antibody response is protective against B . burgdorferi . Bacteria associated with reactive arthritis, namely, Yersinia enterocolitica, Shigella flexneri, and Salmonella enteritidis, had different effects . The molecular definition of pathogen-host interactions determining cytokine production should facilitate rational therapeutic interventions directing the host response towards the desired cytokine response . Here, we describe small synthetic molecules capable of inducing Th1 phenotype development.

J Clin Microbiol, 1997 Oct, 35(10), 2487 - 91
Molecular epidemiology of two international sprout-borne Salmonella outbreaks; Puohiniemi R et al.; Sprout-borne Salmonella outbreaks in Finland have increased during the last 10 years . The latest two were caused by Salmonella enterica serovar Bovismorbificans (antigenic structure 6,8:r:1,5) in 1994 and S . enterica serovar Stanley (4,5, 12:d:1,2) in 1995 . In this study, the restriction fragment length polymorphism of genomic DNA after pulsed-field gel electrophoresis (PFGE) and antimicrobial resistance profiles of the outbreak and nonoutbreak strains were compared . In each separate outbreak, the PFGE patterns of the outbreak strains (40 strains of S . enterica serovar Bovismorbificans and 28 strains of S . enterica serovar Stanley) after digestion of genomic DNA with restriction enzyme XbaI were indistinguishable from each other but differed clearly from those of the nonoutbreak strains (26 strains of S . enterica serovar Bovismorbificans and 40 strains of S . enterica serovar Stanley) . The restriction enzyme XhoI did not differentiate the outbreak and nonoutbreak strains . The S . enterica serovar Stanley strains associated with the outbreak also had a unique antimicrobial resistance pattern, whereas all S . enterica serovar Bovismorbificans strains, both outbreak and nonoutbreak strains, were sensitive to all antimicrobial agents tested . Thus, the molecular typing confirmed that the S . enterica serovar Bovismorbificans outbreak isolates from humans and sprout salad were identical and strongly supported the epidemiological finding that S . enterica serovar Stanley outbreak isolates also originated from contaminated alfalfa seeds . It also confirmed that the sources of similar outbreaks in Sweden in 1994 caused by S . enterica serovar Bovismorbificans and in the United States in 1995 caused by S . enterica serovar Stanley and the source of the Finnish outbreaks were common.

Eur J Pharmacol, 1997 Aug 27, 333(2-3), 181 - 6
Haemodynamic effects of dopexamine and nitric oxide synthase inhibition in healthy and endotoxaemic sheep; Waurick R et al.; Chronically instrumented awake healthy sheep (n = 6) received the synthetic catecholamine, dopexamine, during or without a background infusion of the nitric oxide synthase inhibitor . L-nitro-arginine-methylester (L-NAME) . Three days later, hypotensive-hyperdynamic circulation was induced and maintained by continuous infusion of Salmonella typhosa endotoxin (10 ng/kg per min) . After 24 h of continuous endotoxin infusion, the dopexamine L-NAME protocol was repeated . In healthy and endotoxaemic animals with and without nitric oxide synthase inhibition dopexamine caused the same haemodynamic changes: heart rate and cardiac output increased, mean arterial pressure and systemic vascular resistance decreased . L-NAME infusion induced normalisation of the hypotonic-hyperdynamic circulation in endotoxaemic animals . Dopexamine reduced some adverse effects of L-NAME treatment, like increased pulmonary vascular resistance and decreased oxygen delivery . In conclusion the haemodynamic effects of dopexamine are independent of the amount of nitric oxide production . Dopexamine may attenuate some of the adverse effects of nitric oxide synthase inhibition.

Kansenshogaku Zasshi, 1997 Aug, 71(8), 788 - 92
{A case report--typhoid fever complicated with liver and gallbladder abscess, treated for long-time as fever of unknown origin}; Kawashima I et al.; A 25-year-old male admitted to Kawasaki municipal hospital with the diagnosis of typhoid fever . He had noticed high fever since one month ago, and had been treated with prednisolone with the diagnosis of fever of unknown origin in a hospital . Then he had admitted to St . Marianna University Hospital, and Salmonella Typhi had been detected from his blood and stool . On admission, multiple liver abscess were detected by abdominal ultrasonography . S . Typhi in bile was not eliminated with CP and AMPC, but he was successfully treated with cholecystectomy and the chemotherapy of LVFX . Abscess formation was found in the resected gall bladder wall . Typhoid nodule in the lymph node, liver or other organs is a well known pathological change in the typhoid fever . But abscess formation in the liver or other organs is rare . In this case, multiple abscess is characteristic and this cause is thought to be induced by the factors that the period from onset of typhoid fever to beginning of effective therapy was too long, and that steroid therapy was done without antibiotic therapy.

Kansenshogaku Zasshi, 1997 Aug, 71(8), 745 - 50
{Application of arbitrarily primed polymerase chain reaction analysis to epidemiological study of Salmonella enterica serovar enteritidis}; Hanzaki O et al.; An arbitrarily primed polymerase chain reaction (AP-PCR) DNA profile was applied to epidemiological analysis of Salmonella enterica subsp . enterica serovar Enteritidis . A total 21 strains of S . Enteritidis isolated from 21 cases (10 cases of healthy persons, 7 cases of food poisoning outbreaks and 4 sporadic diarrhea cases), during the period between December 1991 and August 1996 in Wakayama City, were used . A total of 60 arbitrary primers (DNA oligomer (12) set, Wako) were screened with 4 S . Enteritidis strains of different cases . A-11, B-32, C-42 and C-45 primers were chosen . Plasmid DNA profiles, antimicrobial susceptibility patterns and phage types were also examined . The combination of these three methods resolved the collection into five groups (A to E) . And type C strains were found in 17 cases (81%) out of 21 cases . However, according to AP-PCR DNA profile, all 21 strains were classified into six groups (I to VI), and 17 type C strains were classified into three groups (III, IV and V) . Type IV was predominant in Wakayama City, and type C.IV was found in 15 cases (71%) . In conclusion, we considered that AP-PCR DNA profile using appropriate primers was an effective epidemiological marker.

Kansenshogaku Zasshi, 1997 Aug, 71(8), 730 - 7
{Biochemical and molecular characterization of Salmonella serovar enteritidis phage type 4 isolated from food poisoning outbreaks in Tokyo}; Kusunoki J et al.; Since 1989, outbreaks of Salmonella ser . Enteritidis (S . Enteritidis) food poisoning have dramatically increased in Tokyo, and a total of 31 outbreaks has been reported in 1989 . Twenty-one of these 31 outbreaks were caused by S . Enteritidis PT34, but 8 outbreaks were caused by S . Enteritidis PT4 . After 1990 instead of SE PT34, food poisoning due to PT4, which was a very common phage type in the UK, has increased in Tokyo . Between 1989 and 1995, there were 144 food poisoning outbreaks caused by S . Enteritidis, and 64 of these outbreaks were by due to S . Enteritidis PT4, which was one of the main phage types in Tokyo . To characterize these strains of phage type (PT) 4,293 isolates from patients, and vehicle foods, eggs and environment in Tokyo were examined for plasmid DNA profiles, acid productivity from glycols (propylene and ethylene) and antimicrobial resistance patterns . Plasmid DNA was extracted by Kado's method, and analyzed by agarose gel electrophoresis . The acid productivity from propylene glycol or ethylene glycol were tested using Barsicow medium with 1% propylene glycol or ethylene glycol . Antimicrobial susceptibility to AM, CP, TC, SM, KM, NA, ST, FOM and NFLX was tested by the K-B disc method . The strains of PT4 were further subdivided into 9 types by those epidemiologic marker analysis . The prevalent pattern of PT4 strains was type A plasmid profile carrying only one plasmid (60 kb) and there were 2 kinds of antibiograms . One was SM resistant, while the other was susceptible . A total of 56 (87.5%) of 64 outbreaks was found to have been caused by these types of S . Enteritidis . Several kinds of egg-related foods were suspected as the vehicles of transmission among 24 outbreaks . Especially, in 5 outbreaks, S . Enteritidis strains were isolated both from patients and suspected food which were cooked with egg . This strongly suggests that these foods may be the potential source of infection in S . Enteritidis PT4 outbreaks.

FEMS Microbiol Lett, 1997 Sep 15, 154(2), 207 - 13
Sequence analysis and distribution of an IS3-like insertion element isolated from Salmonella enteritidis; Collighan RJ et al.; The nucleotide sequence of a 3 kb region immediately upstream of the sef operon of Salmonella enteritidis was determined . A 1230 base pair insertion sequence which shared sequence identity (> 75%) with members of the IS3 family was revealed . This element, designated IS1230, had almost identical (90% identity) terminal inverted repeats to Escherichia coli IS3 but unlike other IS3-like sequences lacked the two characteristic open reading frames which encode the putative transposase . S . enteritidis possessed only one copy of this insertion sequence although Southern hybridisation analysis of restriction digests of genomic DNA revealed another fragment located in a region different from the sef operon which hybridised weakly which suggested the presence of an IS1230 homologue . The distribution of IS1230 and IS1230-like elements was shown to be widespread amongst salmonellas and the patterns of restriction fragments which hybridised differed significantly between Salmonella serotypes and it is suggested that IS1230 has potential for development as a differential diagnostic tool.

Int J Food Microbiol, 1997 Jul 22, 37(2-3), 241 - 4
A comparison of procedures involving single step Salmonella, 1-2 Test, and modified semisolid Rappaport-Vassiliadis medium for detection of Salmonella in ground beef; Afflu L et al.; Procedures involving Single Step Salmonella (SSS), 1-2 Test, and Modified Semisolid Rappaport-Vassiliadis Medium (MSRV) were compared for their speed and sensitivity in detection of Salmonella in ground beef contaminated with one isolate of each of five Salmonella serotypes . Inocula of 10, 10(2) and 10(3) CFU/g of ground beef were used . When pre-enrichment in buffered peptone water and selective enrichment in tetrathionate broth were used, SSS and MSRV detected all five species of Salmonella at all levels of contamination, whereas the 1-2 Test was positive in 0, 12, and 15 of 15 tests at 10, 10(2) and 10(3) CFU/g, respectively . When only pre-enrichment was used, the results with MSRV were unchanged but the SSS test failed to detect S . typhimurium . Thus, with pre-enrichment the MSRV and SSS procedures were equally sensitive and both produced a result on the third day . The 1-2 Test was less sensitive and slower, with results available on day-4 . The MSRV protocol was best overall.

Int J Food Microbiol, 1997 Jul 22, 37(2-3), 183 - 8
Assay of Salmonella in enrichment cultures of foods, feeds and environmental samples by the polymyxin-cloth enzyme immunoassay; Blais BW et al.; A variety of foods, animal feeds and environmental samples were analyzed for the presence of Salmonella using the polymyxin-cloth enzyme immunoassay (p-CEIA) system . Salmonella lipopolysaccharide (LPS) antigens were captured from test samples on polymyxin-coated polyester cloth, followed by immunoenzymatic detection of bound antigens using a monoclonal antibody recognizing an LPS common core oligosaccharide . Dairy and egg products, animal feeds and environmental samples from food processing plants were pre-enriched for 24 h, followed by selective enrichment for a further 24 h in either tetrathionate brilliant green (TBG), selenite cystine (SC) or brain-heart infusion broth containing 0.5% yeast extract, 0.5% cholate and 0.3% selenite (BYCS) . The samples were assayed by the p-CEIA after each stage of enrichment . After selective enrichment, the p-CEIA gave results which were in complete agreement with the standard culture technique in the analysis of all foods examined . On the other hand, a combination of selective enrichment and the p-CEIA out-performed the Modified Semi-Solid Rappaport Vassiliadis (MSRV) method in screening pre-enrichment cultures of feeds and environmental samples . Use of the new selective medium BYCS prior to performing the p-CEIA gave the highest recovery of Salmonella from feeds and environmental samples.

Eur J Biochem, 1997 Aug 15, 248(1), 217 - 24
Lipopolysaccharide-binding proteins and their involvement in the bacterial clearance from the hemolymph of the silkworm Bombyx mori; Koizumi N et al.; Proteins having the ability to bind to Escherichia coli K12W3110 (rough (R) mutant) were isolated and purified by affinity precipitation from the larval hemolymph of the silkworm Bombyx mori . These proteins were found to consist of two components with molecular masses of 43 kDa and 40 kDa by SDS/PAGE . They bound to all E . coli R mutants (Ra, Rb1, Rc, Rd1 and Re) and Salmonella minnesota R mutants . However, they did not bind to smooth types of the above bacteria . They bound to both lipopolysaccharide(LPS)-coated and lipid-A-coated microtiter plates and have similar dissociation constants for LPS and lipid A . This indicates that the binding proteins recognize the lipid A portion of LPS and thus, we have named these proteins BmLBP (B . mori LPS-binding proteins) . We also found that BmLBP participated in the clearance of E . coli cells injected into the body cavity of the silkworm.

AIDS Res Hum Retroviruses, 1997 Sep 20, 13(14), 1187 - 94
Induction of mucosal and systemic responses against human immunodeficiency virus type 1 glycoprotein 120 in mice after oral immunization with a single dose of a Salmonella-HIV vector; Wu S et al.; Previous studies from our group showed that a Salmonella-HIV vector vaccine that expressed recombinant HIV-1 envelope protein gp120 stably in the vector cytoplasm elicited type 1 helper T cell (Th1) responses to gp120 . Despite the promise of such vaccines, a major limitation in their use was that multiple immunizations were required to elicit even small responses . For this reason, we sought a modified vector configuration that would induce more potent gp120-specific T cell responses exhibiting a broader spectrum of effector functions after a single inoculation . In this article we describe the construction and immunogenicity of a Salmonella-HIV vector that displays a truncated derivative of HIV-1(IIIB) envelope in the periplasm of the vector . A single oral dose of this Salmonella vector, called H683(pW58-asd+), generated a gp120-specific proliferation response in the spleen 14 days after immunization . In agreement with our previous findings, the gp120-specific splenic CD4+ T cells elicited by H683(pW58-asd+) displayed a Th1 phenotype; however, gp120-specific splenic CD4+ Th2 cells were also evident . In addition, this strain induced strong gp120-specific IgA antibody-secreting cell (ASC) responses in the intestinal lamina propria and mesenteric lymph nodes . As many as 2% of the total lamina propria and mesenteric lymph node IgA ASCs were found to be specific for gp120 28 days after a single oral dose of H683(pW57-asd+) . Because the proliferative response following a single dose of H683(pW58-asd+) was comparable to that seen previously after three doses of an analogous construct expressing recombinant gp120 in the cytoplasm, these observations suggest that Salmonella-vectored secreted HIV-1 antigens elicit higher T cell responses than their cytoplasmically bound analogs.

Z Naturforsch {C}, 1997 Jul-Aug, 52(7-8), 413 - 20
New botrydial sesquiterpenoids from Hymenoscyphus epiphyllus; Thines E et al.; Four new botrydial derivatives, hymendial (1), 7 alpha-hydroxydihydrobotrydial (2), 7 alpha-hydroxy-10-O-methyldihydrobotrydial (4), and 7 alpha-acetoxy-15 alpha-methoxy-10-O-methyl-dihydrobotrydial (5) were isolated together with dihydrobotrydial (3) from the culture fluid of the ascomycete Hymenoscyphus epiphyllus . In addition, cytochalasin H (6a), 18-deoxycytochalasin H (6b) and (+)-mellein (7) were produced by this fungus . Hymendial (1), possessing an alpha, beta-unsaturated dialdehyde functionality, exhibits antimicrobial and cytotoxic activities and is mutagenic in the Ames Salmonella assay.

Microb Drug Resist, 1997 Fall, 3(3), 263 - 6
Increase in multiple antibiotic resistance in nontyphoidal salmonellas from humans in England and Wales: a comparison of data for 1994 and 1996; Threlfall EJ et al.; The incidence of multiple drug resistance (to four or more antimicrobials) in salmonellas from humans in England and Wales in 1996 has been compared with corresponding data for 1994 . For Salmonella enteritidis multiple resistance has remained rare, although a high proportion of isolates of phage type 6A have shown resistance to ampicillin . For S . typhimurium multiple resistance has continued to increase, with 81% of isolates now multiresistant . Of particular importance in S . typhimurium has been the continued epidemic of multiresistant DT 104 and the increasing occurrence of strains of this phage type with additional resistance to trimethoprim and/or ciprofloxacin . For S . virchow, a 10% increase in multiple resistance is mainly concentrated in two phage types common in returning travellers . For S . hadar, there has been a substantial increase in the incidence of multiple resistance with over 50% of isolates now multiresistant . Substantial increases in the incidence of resistance to ciprofloxacin in multiresistant S . typhimurium DT 104, S . virchow, and S . hadar since 1993, when the fluoroquinolone antibiotic enrofloxacin was licensed for veterinary use in the UK, are of particular concern.

Behring Inst Mitt, 1997 Feb, (98), 376 - 89
Targeting of mucosal vaccines to Peyer's patch M cells; Frey A et al.; Transepithelial transport of antigens and pathogens is the first step in the induction of a mucosal immune response . In the intestine, the delivery of antigens across the epithelial barrier to the underlying lymphoid tissue is accomplished by M cells, a specialized epithelial cell type that occurs only in the lymphoid follicle-associated epithelium . Selective and efficient transport of antigen by M cells is considered an essential requirement for effective mucosal vaccines . Therefore, particulate antigen formulations are currently being developed to take advantage of the capacity of M cells to endocytose particles . Based on pathogens that exploit the M cell as an invasion route into the body, live mucosal vaccines have been designed using genetically-engineered, attenuated strains of pathogens such as poliovirus and Salmonella . In an alternative approach, antigens are coupled to or encapsulated in particulate synthetic carriers . To enhance binding and uptake of such nonviable vectors, ligands are being attached which direct the vaccine particle to receptors on the M cell surface.

Behring Inst Mitt, 1997 Feb, (98), 24 - 32
Antigen sampling by epithelial tissues: implication for vaccine design; Kraehenbuhl JP et al.; Mucosal surfaces of the respiratory, digestive and urogenital tracts are covered by a specialized epithelium which constitutes an efficient physical barrier against environmental pathogens . These surfaces differ greatly in their cellular organisation and in antigen sampling . In stratified epithelia, professional antigen-presenting cells, the dendritic cells or Langerhans cells, are intimately associated with the epithelial barrier and take up samples of foreign material from the external environment which they transport to local or distant organized lymphoid tissues . In simple epithelia highly specialised cells, the so-called M cells, sample foreign material and microorganisms and deliver them by transepithelial transport from the lumen to the underlying organized lymphoid tissue (MALT) . The interaction of lymphocytes with the follicle-associated epithelium (FAE) is responsible for the loss of digestive functions and the acquisition of transepithelial transport activity . The three way interaction of epithelium, lymphoid cells, and microorganisms seen in the FAE which controls the formation of MALT provides a dramatic demonstration of the phenotypic plasticity of the intestinal epithelium and probably of all simple epithelia . We have shown that all mucosal surfaces, covered by stratified or simple epithelia are able to sample and transport live recombinant bacterial vaccines, which elicit systemic and local immune responses against the carrier and the foreign antigen . In gut and nasal-associated lymphoid tissue, Salmonella are taken up by dendritic cells which form a dense cellular network in the dome regions of MALT . Targeting bacterial vaccine candidates to dendritic or M cells is likely to facilitate their sampling by epithelial tissues and to contribute to strong mucosal and systemic immune responses.

Behring Inst Mitt, 1997 Feb, (98), 197 - 211
Bacterial antigen delivery systems: phagocytic processing of bacterial antigens for MHC-I and MHC-II presentation to T cells; Svensson M et al.; Using an in vitro model system we have studied parameters of both bacteria and antigen presenting cells that influence peptide presentation by murine major histocompatibility complex class II (MHC-II) and class I (MHC-I) molecules . To study MHC-II presentation, the HEL (52-61) epitope, which binds the murine MHC-II molecule I-Ak, was expressed as the cytoplasmic Crl-HEL fusion protein in S . typhimurium . When murine peritoneal macrophages mediated phagocytic processing of S . typhimurium expressing Crl-HEL, HEL (52-61) was processed and presented on I-Ak more efficiently from heat-killed S . typhimurium than from viable bacteria, and from a rough LPS strain compared to its isogenic smooth LPS counterpart, most likely due to enhanced phagocytosis of the rough LPS strain . Macrophages also processed phoP S . typhimurium strains with greater efficiency for peptide presentation by I-Ak than wild type bacteria while Salmonella constitutively expressing phoP were processed for peptide presentation by I-Ak less efficiently than wild type Salmonella . We have also shown that macrophage phagocytosis of E . coli or S . typhimurium results in presentation of bacterial antigens by MHC-I molecules . To investigate the role of post-Golgi MHC-I molecules in this presentation pathway, peritoneal macrophages from TAP1-/- mice, which are deficient in presenting endogenous antigens on MHC-I and lack significant surface MHC-I expression, were co-incubated with bacteria containing the 257-264 epitope from ovalbumin {OVA(257-264)}, which binds the murine class I molecule Kb . Peritoneal macrophages from TAP1-/-/ mice could process bacteria expressing the OVA epitope for recognition by epitope-specific T hybridoma cells . This processing and presentation was reduced in efficiency between three to 100 fold compared to C57BL/6 macrophages, depending on the protein harbouring the OVA (257-264) epitope (Crl-OVA or native OVA) . This suggests that the protein context of the OVA (257-264) epitope influences the extent of TAP-independent processing for MHC-I presentation . In addition, we show that murine bone marrow-derived dendritic cells can phagocytose and process viable gram negative bacteria for peptide presentation on MHC-I and MHC-II; inhibition studies showed that acidic compartments in dendritic cells are required for this presentation . These results suggest that dendritic cells may be potential antigen presenting cells used in eliciting specific immune responses against bacteria.

Behring Inst Mitt, 1997 Feb, (98), 143 - 52
Oral bacterial vaccine vectors for the delivery of subunit and nucleic acid vaccines to the organized lymphoid tissue of the intestine; Pascual DW et al.; Bacterial vaccine vectors have the potential to deliver a number of antigens from bacterial, protozoan and viral pathogens . To further develop the utility of bacterial vaccine vectors we are currently evaluating three model systems: 1 . A Salmonella-ETEC Vaccine Vector; 2 . A Salmonella-HIV Vaccine Vector, and 3 . Novel Live Bacterial Nucleic Acid Vaccine Vectors . Through our studies, and those of others, significant progress has been made toward bacterial vaccine vector systems that effectively deliver subunit and nucleic acid vaccines to the organized lymphoid tissue of the intestine . The practical reality of these findings is discussed.

Behring Inst Mitt, 1997 Feb, (98), 135 - 42
Expression and immune response to foreign epitopes in bacteria . Perspectives for live vaccine development; Charbit A et al.; We previously developed a general procedure which allows the genetic coupling of a chosen foreign linear epitope in different regions of a carrier protein . By using as carriers, two bacterial envelope proteins, the LamB and MalE proteins of E . coli K12, we were able to express the same epitope in different sites of the two proteins and in different compartments of the bacteria . This allowed us to analyze the influence of the localization in E . coli cells of a foreign B-cell epitope on the induction of specific antibody responses, and the role of the molecular environment on the immunological properties of foreign B- or T-cell epitopes, using either purified hybrid proteins or live recombinant bacteria . Several LamB and MalE hybrid proteins were expressed in the aroA attenuated strain of S . typhimurium, SL3261 . Immunizations of mice with live recombinant bacteria by the intravenous route showed that it was possible to induce humoral responses against inserted foreign sequences . In order to improve the in vivo stability of the plasmids carrying the different contructions, and to increase the amounts of recombinant LamB and MalE hybrid proteins expressed in vivo, the LamB and malE genes were placed under the control of the anaerobically inducible pnirBpromoter control . The genetic factors susceptible of influencing the immune response to recombinant Salmonella in mice were also studied.

J Biotechnol, 1997 Aug 28, 56(3), 191 - 203
Expression and immunogenicity of V3 loop epitopes of HIV-1, isolates SC and WMJ2, inserted in Salmonella flagellin; Cattozzo EM et al.; Synthetic oligonucleotides corresponding to specific V3 loop portions of two HIV-1 isolates, SC and WMJ2, were expressed in the flagella of a Salmonella live-vaccine strain . Expression of the inserted epitopes in flagellin and their exposure at the surface of flagellar filaments were shown by immunoblotting and immunogold labeling with anti-flagellin (Salmonella d) and anti-HIV-1(IIIB) V3 loop peptide sera . Live recombinant Salmonella strains expressing either one of the two V3 loop inserts were administered intraperitoneally to BALB/c mice . All these animals developed antibodies specific for the heterologous glycoprotein 120 (gp120) of HIV-1 MN strain, as detected by enzyme-linked immunosorbent assays (ELISA), two of the sera had neutralizing activity against the heterologous HIV-1 MN strain . Moreover, oral administration of the live Salmonella recombinant strains to mice evoked specific IgA directed against gp120.

Mol Plant Microbe Interact, 1997 Sep, 10(7), 926 - 8
The activity of lipid A and core components of bacterial lipopolysaccharides in the prevention of the hypersensitive response in pepper; Newman MA et al.; Pre-treatment of leaves of pepper (Capsicum annuum) with lipopolysaccharide (LPS) preparations from enteric bacteria and Xanthomonas campestris could prevent the hypersensitive response caused by an avirulent X . campestris strain . By use of a range of deep-rough mutants, the minimal structure in Salmonella LPS responsible for the elicitation of this effect was determined to be lipid A attached to a disaccharide of 2-keto-3-deoxyoctulosonate; lipid A alone and the free core oligosaccharide from a Salmonella Ra mutant were not effective . For Xanthomonas, the core oligosaccharide alone had activity although lipid A was not effective . The results suggest that pepper cells can recognize different structures within bacterial LPS to trigger alterations in plant response to avirulent pathogens.

Zh Mikrobiol Epidemiol Immunobiol, 1997 May-Jun, (3), 76 - 81
{The unknown functions of heterologous antigens of different origins}; Nikolaeva AI; After a single injection of 125I-labeled erythrocytic antigen to mice, the protein determinants of this antigen were found in nuclear RNP of B lymphocytes of the immune animals . On day 2 after the injection of Shigella sonnei phase I LPS (also containing protein) to mice hybridization between total RNA isolated from B lymphocytes and 32P-labeled plasmid pSS 120, controlling the synthesis of the S . sonnei phase I antigen, was observed . On day 1 after immunization no hybridization between cell RNA and plasmid pSS 120 occurred . Besides, no hybridization of plasmid DNA with the RNA of nonimmune animals or with RNA, obtained on day 3 after the injection of Salmonella kentucky LPS to mice, was observed . The signal indicating the occurrence of hybridization between the RNA of immune B lymphocytes and plasmid pSS 120 appeared on day 2 and increased on days 3 and 5 after the injection of the antigen . This was seemingly indicative of the accumulation of new nucleotide sequences, complementary to the gene controlling the synthesis of the heterologous antigen which caused immune response, in immune B lymphocytes.

G Chir, 1997 Apr, 18(4), 222 - 8
{Non-parasitic splenic cysts}; Teneriello FL et al.; Nonparasitic cysts of the spleen are uncommon and often result from blunt abdominal trauma . Nonsurgical management of blunt splenic injuries increases the number of observations of the post-traumatic cysts . Complications (infection, rupture and hemorrhage) are lifethreatening, difficult to diagnose and require urgent surgical management . Until recently, splenectomy has been the primary choice of treatment of these cysts . Small (< 4 cm) asymptomatic post-traumatic pseudocysts stand a reasonable chance of involution with time (3-36 months) and so may be initially observed . Splenic preservation by partial splenectomy, enucleation or by marsupialization is actually recommended in children when technically feasible . Splenectomy is required for voluminous, central, multifocal cysts, in the presence of complications and in the adults with low immunologic risk . The Authors report 5 cases of large cysts successfully treated by splenectomy with one 12-year-old girl treated in emergency for infection by Salmonella.

Vaccine, 1997 Aug-Sep, 15(12-13), 1319 - 22
Expression of the serine rich Entamoeba histolytica protein (SREHP) in the avirulent vaccine strain Salmonella typhi TY2 chi 4297 (delta cya delta crp delta asd): safety and immunogenicity in mice; Zhang T et al.; Infection by the intestinal protozoan parasite Entamoeba histolytica remains a significant threat to health in much of the world . Here we describe the successful expression of the serine rich Entamoeba histolytica protein (SREHP), a protective antigen of ameba, in an attenuated vaccine strain Salmonella typhi TY2 chi 4297 (delta cya delta crp delta asd) . The attenuation of S . typhi TY2 chi 4297 was not altered by expression of the SREHP-maltose binding protein (MBP) fusion protein and mice parenterally vaccinated with S . typhi TY2 chi 4297 expressing SREHP-MBP developed serum anti-amebic and anti-LPS antibodies . S . typhi TY2 chi 4297 expressing SREHP-MBP represents a prototype combination vaccine designed to prevent both amebiasis and typhoid fever.

Lupus, 1997, 6(7), 610 - 2
Fatal amoebic colitis in a patient with SLE: a case report and review of the literature; Tai ES et al.; Colitis in systemic lupus erythematosus (SLE) poses a diagnostic challenge as clinical, radiological and laboratory findings are often non-specific . Fulminant amoebic colitis is a rare cause of death in SLE . Early diagnosis coupled with timely surgery can reduce the mortality . The demonstration of haematophagous trophozoites in the stool is diagnostic but insensitive . Early endoscopy with adequate specimen collection is an important part of the diagnosis . Serology is both sensitive and specific but can take up to 2-4 weeks for seroconversion making it less useful in a disease that takes a rapid downhill course if treated inappropriately . We report a fatal case of colitis in a patient with SLE due to invasive amoebiasis which was complicated by Salmonella bacteraemia, disseminated intravascular coagulation, acute oliguric renal failure and adult respiratory syndrome . We also reviewed the literature on the clinical features and diagnosis of fulminant amoebic colitis . Amoebic colitis, although rare, should be considered in the differential diagnosis of lupus patients with colitis.

Clin Diagn Lab Immunol, 1997 Sep, 4(5), 587 - 91
Field evaluation of an immunoglobulin G anti-F1 enzyme-linked immunosorbent assay for serodiagnosis of human plague in Madagascar; Rasoamanana B et al.; Bacteriological isolation of Yersinia pestis is the reference test for confirming plague infection, but recovery of the pathogen from human samples is usually very poor . When the etiology of the disease cannot be bacteriologically confirmed, it may be useful to possess alternative tests such as detection of specific circulating antibodies to help guide the diagnosis . In the present study, the immunoglobulin G (IgG) anti-F1 enzyme-linked immunosorbent assay (ELISA) has been applied to various human sera to evaluate its large-scale applicability in the high-endemicity plague foci of Madagascar . The sensitivity of the test was found to be 91.4%, and its specificity was 98.5% . The positive and negative predictive values were 96 and 96.6%, respectively . Seroconversion was observed on day 7 after onset of the disease . Patients with a positive ELISA result could be separated into high (82%) and low (18%) IgG anti-F1 responders . Cross-reactions with eight other infectious diseases prevalent in Madagascar were scarce and were found in 1 of 27 Mycobacterium tuberculosis-, 3 of 34 Schistosoma haematobium-, and 1 of 41 Salmonella-infected patients . Finally, the efficiency of the IgG anti-F1 ELISA was evaluated during the Mahajanga, Madagascar, plague outbreak of 1995 . When the number of ELISA-positive patients was added to the number of bacteriologically confirmed and probable cases, the number of positive patients was increased by 35% . In conclusion, although it does not replace bacteriology, IgG anti-F1 ELISA is a useful and powerful tool for retrospective diagnosis and epidemiological surveillance of plague outbreaks.

Ann Vasc Surg, 1997 Sep, 11(5), 533 - 5
Infectious aortitis due to penicillin-resistant Streptococcus pneumoniae; Maclennan AC et al.; Infectious aortitis is uncommon and typically affects elderly immunocompromised men, with a Salmonella or Staphylococcal infection of an atheromatous or aneurysmal aorta . We present a fit young man who developed infectious aortitis with peripheral embolization due to a penicillin-resistant Streptococcus pneumoniae bacteremia.

Ann Vasc Surg, 1997 Sep, 11(5), 453 - 63
Infected aneurysms of the infrarenal abdominal aorta: diagnostic criteria and therapeutic strategy; Sessa C et al.; From 1976 to 1994 we performed surgical treatment of 18 infected aneurysms of the infrarenal abdominal aorta . The aneurysm had ruptured in nine patients: into the retroperitoneum in six patients, and into an adjacent structure in three patients (duodenum, inferior vena cava, left renal vein) . Two patients had an associated spondylitis . Four patients were in shock at the time of surgical treatment . Six patients (including four patients with Salmonella infection and two patients with spondylitis) had positive preoperative blood cultures . Salmonella was the most common microorganism (27%) . Anaerobes accounted for 16% . In situ replacement was performed in 13 patients including three procedures performed under emergency conditions with frank purulent infection . Extraanatomic bypass was performed in five patients . Early postoperative death occurred in two patients (11%) due to septic complications (rupture of aortic anastomosis in one patient and rupture of aortic stump in one patient) . All surviving patients underwent prolonged antibiotic therapy for at least 6 weeks . Overall mortality secondary to infected aneurysm was 16% . Infection of the aortic graft occurred in four patients (38%) including two patients with Salmonella infection and one patient with spondylitis . One patient developed a false anastomotic aneurysm 6 months postoperatively and was treated by in situ arterial allograft replacement . Postoperative blood cultures were positive in two patients presenting spondylitis and infection of the aortic prosthesis occurred in one of these patients . In addition to rupture, poor prognostic factors included spondylitis and Salmonella infection that were found to greatly enhance the risk of postoperative graft infection following in situ reconstruction.

Environ Health Perspect, 1997 Sep, 105(9), 940 - 8
Allergic contact sensitizing chemicals as environmental carcinogens; Albert RE; Chemicals that were bioassayed by the National Toxicology Program (NTP) and that also produce allergic dermatitis (ACD) in humans were evaluated for their tumorigenic characteristics . The impetus for the study was that most contact sensitizers, i.e., those that produce ACD, and genotoxic carcinogens are chemically similar in that they are electrophilic, thereby producing adducts on macromolecules including protein and DNA . This similarity in chemical behavior suggests that many contact sensitizers might be environmental carcinogens . All of the published NTP bioassays by early 1996 that had both genotoxicity and carcinogenicity studies were included in this analysis . The NTP chemicals had been chosen for bioassay without regard to their ability to produce ACD . Of the 209 chemicals that were bioassayed, there were 36 (17%) that were known to be human contact sensitizers; about half of these were positive on tumor bioassays . The contact sensitizers differed from the NTP sample as a whole by having a proportionately larger number of nongenotoxic chemicals by the Ames Salmonella assay, presumably because more of them were selected on the basis of widespread usage rather than structural resemblance to known carcinogens . Compared to the nongenotoxic chemicals, the genotoxics were stronger carcinogens in that they had a higher incidence of positive tumor bioassays, with twice the number of organs in which tumors were induced . The nongenotoxic chemicals had a preference for tumor induction in parenchymal tissues in contrast to epithelial tissues . The contact sensitizers showed essentially the same characteristics as the whole NTP sample when stratified according to genotoxicity . Judging by the chemicals that were chosen primarily for their widespread use rather than for their structural resemblance to carcinogens, the addition of a test for contact sensitization to the Ames test as a screening tool would increase the tumorigenic detection efficiency by about 40% because of the nongenotoxic tumorigens . A ballpark estimate suggests that there could be several thousand contact sensitizers for humans in commercial use that are rodent tumorigens.

Biol Chem, 1997 Aug, 378(8), 815 - 9
RAGged repair: what's new in V(D)J recombination; Hagmann M; Antigen-specific immunity is due to the generation of a multitude of both immunoglobulins and T-cell receptors through a process designated V(D)J recombination . In vitro reconstitution of this system has taught us a great deal about the molecular mechanism underlying this site-specific recombination process . Hence, it became obvious that the initial steps of the reaction are carried out by the lymphocyte-specific proteins RAG1 and RAG2 (recombination-activating genes), with the help of members of the high mobility group protein family of DNA-binding proteins, HMG1 or HMG2 . Structural resemblance between RAG1 and a prokaryotic recombinase, the Salmonella Hin Recombinase, together with mechanistic similarities between V(D)J recombination and bacterial transposition reactions, make it likely that these different processes have evolved from a common ancestral recombination system . The second step in V(D)J recombination is catalysed by the ubiquitous DNA double-strand break repair machinery . The link between V(D)J recombination and double-strand break repair was established through some mutational complementation groups, including the murine SCID mutation (severe combined immunodeficiency), which were shown to be defective in both V(D)J recombination and double-strand break repair . The multisubunit DNA-dependent protein kinase appears to be a key player in these processes . Thus, from an evolutionary point of view, antigen-specific immunity in mammals, e.g., humans and mice, appears to be the result of an evolutionary combination of two unrelated systems involved in DNA metabolism.

Gene, 1997 Aug 11, 195(1), 93 - 100
Sequence comparison of the genes for immunity, DNA replication, and cell lysis of the P22-related Salmonella phages ES18 and L; Schicklmaier P et al.; Complementation and hybridization experiments with the generalized transducing Salmonella phages P22, ES18 and L revealed strong similarity between the phages L and P22; the genome of ES18 shows a mosaic structure . About half of its genome, including the early genes, is similar or completely homologous to P22; the other half of the morphologically different ES18 does not show any similarity to P22 nor to E . coli phage lambda . Sequence comparison of the early genes has confirmed that the C-immunity region of ES18 is identical with that of P22, whereas the same region of phage L shows poor (repressor gene) or no similarity . The 5'-terminus of the DNA replication gene 12 of ES18, however, is homologous to the same section of gene O of phage lambda . The lysis genes of ES18 again are identical to those of P22; only gene 15 is mosaic-like and has more similarity to gene Rz of phage lambda . These results will be discussed in terms of the theory of modular genome organization.

Haematologica, 1997 Jul-Aug, 82(4), 415 - 9
Bacteremia in patients with hematological malignancies . Analysis of risk factors, etiological agents and prognostic indicators; Pagano L et al.; BACKGROUND AND OBJECTIVE: Patients with hematological malignancies are at increased risk for developing bacteremia . No previous study has investigated the risk and prognostic indicators of bacteremia in such patients using a statistical approach . METHODS: A case-control study was performed in 106 patients with hematological malignancies (group A) . Two hundred and twelve patients were included as controls and divided into two groups: 106 patients with hematological malignancy without bacteremia (group B) and 106 HIV-infected patients with bacteremia (group C) . RESULTS: At univariate analysis, bacteremia risk factors in group A were: neutropenia for more than six days (p = 0.03 vs . group B), central venous catheter usage (p = 0.04) and absence of antibiotic prophylaxis (p = 0.03) . At multivariate analysis, the use of CVC and neutropenia were independent bacteremia risk factors . The most frequent etiological agents were: Staphylococcus epidermidis and Pseudomonas aeruginosa . Comparing groups A and C, the distribution of Staphylococcus spp . was different, with S . epidermidis being prevalent in hematological patients only . As regards gram-negative organisms, it is of note that no episode of NT-Salmonella bacteremia was observed in group A, unlike group C, where they represent the second leading etiological agents . In group A, 14% of the patients died . Persistent neutropenia (p = 0.01) and the presence of relapsed neoplasm (p = 0.04) were prognostic indicators of bacteremia . INTERPRETATION AND CONCLUSIONS: Our findings suggest that bacteremia in patients with hematological malignancies strictly correlates with the intensity and length of neutropenia and CVC usage . Although we observed a low mortality rate, we stress that this clinical condition requires special attention from the physician, who must recognize and treat it promptly.

Pathol Biol (Paris), 1997 May, 45(5), 415 - 9
In vitro activity of cefixime versus ceftizoxime against Salmonella typhi; Rastegar Lari A et al.; Emergence of multi-resistant strains of Salmonella typhi is a major problem in treatment of typhoid fever and requires an excessive hospitalization period . Therefore, the present study was carried out to estimate the degree of the resistance of S . typhi strains to various antibiotics such as cefixime . Fifty two strains of Salmonella typhi isolated from patients with typhoid fever and their sensitivity to various antibiotics was determined . MICs of cefixime and chloramphenicol were also determined according to comitee de l'antibiogramme francais . Results indicated that 41.9%, 33.9%, 38.7%, 58.1% and 1.6% of isolated strains were resistant to chloramphenicol, co-trimoxazole, ampicillin, tetracycline and gentamycin respectively . About one third (33.9%) of strains showed multiple resistance to the first four mentioned antibiotics . All strains were susceptible to ceftizoxime and cefixime (MICs 1 and less than 1 mcg/ml) . It could be concluded that cefixime due to its effectiveness, oral administration and shorter courses of treatment could be the therapy of choice in cases of typhoid fever caused by multiple resistant strains especially when we have a shortage of hospital beds.

Collegian, 1997 Jul, 4(3), 36 - 7
Salmonella: a villain in 'food poisoning'; Leaver M; The majority of these reports occurred during and shortly after the hottest summer recorded in Melbourne . It has been suggested that meat coming from the abattoirs may have carried a higher than usual load of organisms . Variability of the severity of the symptoms is related to host factors and food handling as well as to the virulence of the particular serovar . Investigations by the staff of the Department of Human Services revealed some major errors in food handling in some situations and minor breaches in others . Mishandling by consumers is also likely (Lester et al 1997) . Such outbreaks serve to remind us not only of the importance, particularly in hot weather, of careful handling of meat, especially smallgoods, but also of the need for rapid notification to the appropriate authority of diarrhoeal illness where food is suspected to be the cause.

Trends Microbiol, 1997 Sep, 5(9), 343 - 9
How Salmonella became a pathogen; Groisman EA et al.; In many pathogens, virulence can be conferred by a single region of the genome . In contrast, the facultative intracellular lifestyle of Salmonella demands a large number of genes distributed around the chromosome . The evolution of Salmonella has been marked by the acquisition of several 'pathogenicity islands', each contributing to the unique virulence properties of this microorganism.

Rev Inst Med Trop Sao Paulo, 1996 Sep-Oct, 38(5), 315 - 22
Changing patterns of Salmonella serovars: increase of Salmonella enteritidis in São Paulo, Brazil; Tavechio AT et al.; Serovars of a total of 5,490 Salmonella strains isolated during the period of 1991-95, from human infections (2,254 strains) and from non-human materials (3,236 strains) were evaluated . In the studied period, 81 different serovars were determined among human isolates . Salmonella Enteritidis corresponded to 1.2% in 1991, 2% in 1992, 10.1% in 1993, 43.3% in 1994, and 64.9% in 1995 of all isolates . A significant rise on the isolation of this serovar was seen since 1993 linked to food poisoning outbreaks . It is reported also an increase on the isolation of S . Enteritidis from blood cultures, associated mainly with patients with immunodeficiency syndrome . S . Enteritidis was prevalent among one hundred and thirty different serovars isolated from non-human sources . Increasing number of isolation of this serovar was seen from shell eggs, breeding flocks and from environmental samples . It is also reported a contamination of commercial feed stuffs by S . Enteritidis which represents a major concern for Brazilian poultry industry.

Proc Natl Acad Sci U S A, 1997 Sep 2, 94(18), 9887 - 92
A secreted Salmonella protein with homology to an avirulence determinant of plant pathogenic bacteria; Hardt WD et al.; Bacterial pathogens have evolved sophisticated mechanisms to interact with their hosts . A specialized type III protein secretion system capable of translocating bacterial proteins into host cells has emerged as a central factor in the interaction between a variety of mammalian and plant pathogenic bacteria with their hosts . Here we describe AvrA, a novel target of the centisome 63 type III protein secretion system of Salmonella enterica . AvrA shares sequence similarity with YopJ of the animal pathogen Yersinia pseudotuberculosis and AvrRxv of the plant pathogen Xanthomonas campestris pv . vesicatoria . These proteins are the first examples of putative targets of type III secretion systems in animal and plant pathogenic bacteria that share sequence similarity . They may therefore constitute a novel family of effector proteins with related functions in the cross-talk of these pathogens with their hosts.

J Bacteriol, 1997 Sep, 179(17), 5398 - 406
Mutational characterization of promoter regions recognized by the Salmonella dublin virulence plasmid regulatory protein SpvR; Grob P et al.; The virulence plasmid-encoded spv regulon is essential for virulence of Salmonella dublin in mice . The spvR gene product belongs to the LysR family of transcriptional regulator proteins . SpvR induces the expression of the spvABCD operon and positively regulates its own expression . DNase I protection analysis with purified SpvR fusion proteins identified SpvR binding sites within the spvA and spvR promoters (P . Grob and D . G . Guiney, J . Bacteriol . 178:1813-1820, 1996) . We have used PCR mutagenesis, combined with functional selection for reduced SpvR affinity, to define the DNA elements essential for SpvR binding . For the spvR promoter fragment, a screen for reduced expression was also applied . Sequence analysis of the resulting mutant fragments reveals that the base pair changes are clustered in distinct regions . Determination of the apparent dissociation constants of SpvR for the mutant promoters showed that the spvA LysR-type motif and the upstream palindromic sequences of both promoters play an important role in SpvR recognition.

Poult Sci, 1997 Sep, 76(9), 1232 - 8
Preharvest sources of Salmonella colonization in turkey production; Hoover NJ et al.; An ecological survey was conducted from March, 1995 to February 1996 to determine sources of Salmonella colonization in two flocks of turkeys reared consecutively in a newly constructed facility . Sampling was conducted prior to placement of poults, at Day 0, and again at 2, 10, 14, and 18 wk . Samples were collected at comparable times for the second flock except that final sampling occurred at 22 wk instead of 18 wk . Poult box liners, birds, new litter, drinkers, and air were sampled . Feed was collected from each shipment upon arrival at the facility . Feeders, drinkers, and used litter were monitored to evaluate horizontal transmission . Conventional methods for isolation and serological screening were used to analyze samples for the presence or absence of Salmonella . Prior to placement of the first flock, litter, drinkers, and air samples were negative for the presence of Salmonella, whereas drinkers were positive prior to placement of the second flock . Following placement of poults, 51.1, 63.8, and 22.8% of all litter, drinker, and air samples, respectively, were positive . Salmonella was isolated from 13.6% of poult box liners, 25.0% of yolk sac samples, and 53.8% of ceca, excluding Day 0 . Salmonella was isolated from 14.8% of feed shipments and 39.1% of feeder contents . Frequency of Salmonella detection was higher P < 0.05) in Flock 1 than Flock 2 for cecal and air samples . Salmonella colonization of turkey flocks and the spread of Salmonella within the environment was extensive once initial contamination of the production house occurred . Drinkers, feeders, litter, and air were critical sources of horizontal transmission within each pen as well as between pens.

Poult Sci, 1997 Sep, 76(9), 1212 - 9
Preservation of hatchery waste by lactic acid fermentation . 1 . Laboratory scale fermentation; Deshmukh AC et al.; In Experiment 1, two types of hatchery wastes, including cockerel chicks (CC), and shell waste (SW) blended with CC (60:40 CC:SW), were ground and mixed with a by-product carbohydrate (5, 10, and 15% wt/wt) with or without a bacterial culture and fermented for a period of 21 d . Cockerel chicks fermented with 15% carbohydrate and the culture had a pleasant smell and little H2S production . Elevated H2S concentrations were recorded for CC:SW samples at all carbohydrate levels when the culture was not added . No NH3 was detected from any treatments during fermentation . The addition of culture to the CC and CC:SW by-products resulted in pH values lower (P < 0.05) than those without culture on Day 21, and the 15% carbohydrate treatment significantly reduced pH beyond the 5% carbohydrate . Final proximate composition of CC and CC:SW samples with culture were not significantly different from those without culture added . In Experiment 2, carbohydrate was added at 10.0, 13.3, 16.7, and 20.0% wt/wt to CC and CC:SW in the presence of the bacterial culture . Shell waste alone was fermented with 15, 20, and 25% carbohydrate and the culture . Moisture level in this experiment was adjusted to approximately 70% for all treatments . The lowest pH for the CC and CC:SW treatments was observed at the 16.7% carbohydrate level . Shell waste pH was better maintained at the 20 and 25% carbohydrate levels . After fermentation for 21 d CC, CC:SW and SW treatments from Experiments 1 and 2 contained negligible Escherichia coli, and no Salmonella were detected.

J Toxicol Environ Health, 1997 Sep, 52(1), 35 - 44
Mutagenicity of scooter exhaust particulate matter; Zhou W et al.; By using the in vitro Ames Salmonella/microsomal assay and the in vivo mouse micronucleus assay, studies were performed to evaluate the genotoxicity of gasoline exhaust particulate matter generated from five different domestic and imported scooters . In the Ames assay, treatment of test strains TA98 and TA100 with solvent extracts of particulate matter from four of five scooter models caused an increase in the number of histidine-independent colonies over the background in TA98 without S9 mix . Positive results were also obtained from the micronucleus assay . The frequencies of bone marrow micronucleated polychromatic erythrocytes were significantly higher in the treated compared to the nontreated animals, and the increases in the frequencies were not significantly different among the five types of scooters . Analyses of chemical components showed that scooter exhaust particulate matter contained more than 100 different substances including polycyclic aromatic hydrocarbons.

Blood, 1997 Aug 15, 90(4), 1673 - 83
Downregulation of the proinflammatory cytokine response to endotoxin by pretreatment with the nontoxic lipid A analog SDZ MRL 953 in cancer patients; Kiani A et al.; Interfering with the endotoxin-mediated cytokine cascade is thought to be a promising approach to prevent septic complications in gram-negative infections . The synthetic lipid A analog SDZ MRL 953 has been shown to be protective against endotoxic shock and bacterial infection in preclinical in vivo models . As part of a trial of unspecific immunostimulation in cancer patients, we conducted a double-blind, randomized, vehicle-controlled phase I trial of SDZ MRL 953 to investigate, first, its biologic effects and safety of administration in humans and, second, its influence on reactions to a subsequent challenge of endotoxin (Salmonella abortus equi) . Twenty patients were treated intravenously with escalating doses of SDZ MRL 953 or vehicle control, followed by an intravenous application of endotoxin (2 ng/kg of body weight {BW}) . Administration of SDZ MRL 953 was safe and well-tolerated . SDZ MRL 953 itself increased granulocyte counts and serum levels of granulocyte colony-stimulating factor (G-CSF) and interleukin-6 (IL-6), but not of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha), IL-1beta, and IL-8 . Compared with vehicle control, pretreatment with SDZ MRL 953 markedly reduced the release of TNF-alpha, IL-1beta, IL-8, IL-6, and G-CSF, but augmented the increase in granulocyte counts to endotoxin . Induction of tolerance to the endotoxin-mediated cascade of proinflammatory cytokines by pretreatment with SDZ MRL 953 in patients at risk may help to prevent complications of gram-negative sepsis.

J Mol Biol, 1997 Aug 15, 271(2), 178 - 94
Quantitative specificity of the Mnt repressor; Fields DS et al.; The Mnt protein of Salmonella phage P22 binds site-specifically to its operator . To better understand this binding we used dideoxy DNA sequencing in a quantitative manner to determine the relative binding constants, and hence the relative free energies, of wild-type Mnt protein to a substantial number of variants of its operator . These measurements were supported by experiments which used the SELEX procedure to generate a set of operators from an initially randomized population . In the Discussion we show that the present model of Mnt protein/operator binding, due to Sauer and co-workers, along with the assumption of an independent contribution of each position in the operator to the total binding, provides a reasonably accurate description of the system . We also discuss the use of information content as a measure of DNA-protein binding specificity with the Mnt protein/operator system serving as an example and show again that the assumption of independence supports the current view of this case of site-specific binding.

Mutat Res, 1997 Aug 1, 378(1-2), 89 - 95
Correlation of mutagenic potencies of various petroleum oils and oil coal tar mixtures with DNA adduct levels in vitro; Reddy MV et al.; An in vitro system was utilized to measure DNA adduct-forming ability of petroleum oils and oil coal tar mixtures to define correlations between DNA adduct levels and their mutagenic potencies . The system consisted of reaction of dimethyl sulfoxide extracts of oils with calf thymus DNA in the presence of Aroclor-induced hamster liver microsomes for 30 min . Following DNA extraction, DNA adducts were measured by the nuclease P1-enhanced postlabeling assay coupled with two-dimensional polyethyleneimine (PEI)-cellulose TLC . Thin layer plates showed putative aromatic DNA adducts, with levels ranging from 60 to 1400 adducts per 10(9) DNA nucleotides . TLC mobilities suggested adducts to be aromatic compounds containing 4 or more rings . A good correlation (coefficient of correlation = 0.91) was observed between DNA adduct levels and Salmonella mutagenicity for 19 oils . All 19 samples tested produced DNA adducts . To expedite the TLC procedure, adducts were resolved by one-dimensional TLC and the radioactivity measured using a mechanical scanner . Results were comparable to those obtained by two-dimensional TLC and quantification after scraping . Our data show that the in vitro incubation system coupled with the postlabeling adduct assay is a useful screening method to identify mutagenic and potentially carcinogenic oils.

Epidemiol Infect, 1997 Aug, 119(1), 15 - 23
Salmonella isolated from humans, animals and other sources in Canada, 1983-92; Khakhria R et al.; A total of 89760 human and 22551 non-human isolates of salmonella were serotyped in Canada during the period 1983-92 . There were 2180 reported outbreaks associated with 10065 cases during the 10-year period . The most common salmonella serovars isolated from human and non-human sources were S . typhimurium and S . hadar . The third and fourth most common serovars from human sources were S . enteritidis and S . heidelberg, respectively, and from non-human sources they were S . heidelberg and S . infantis . The number of S . typhimurium isolations from human and non-human sources showed a downward trend over the 10-year period . A total of 222 outbreaks of S . typhimurium associated with 1622 cases occurred . The S . hadar isolations from human and non-human sources reached a peak during the years 1987-90 and declined thereafter . The number of human isolates of S . enteritidis increased until 1985 and fluctuated at a level of 8.3-12.8% of all human isolates thereafter . Seventy-three outbreaks of S . enteritidis infection associated with 568 cases occurred . More than 50% of the S . enteritidis infections in humans were caused by phage type (PT) 8 . During the review period, infections caused by PT4 were less common and were almost exclusively found in people who had travelled abroad . The annual isolation rates of S . heidelberg from human and non-human sources increased steadily during the period . Bacteriophage typing of serovars from outbreaks showed that contaminated food products of poultry and bovine origin were common sources of human infection . Salmonella typhi was identified as the cause of 43 small outbreaks affecting 116 persons.

Neth J Med, 1997 Aug, 51(2), 83 - 6
Management of Salmonella infections during pregnancy and puerperium; van der Klooster JM et al.; The case history of a neonatal infection caused by Salmonella enteritidis group D is presented . The mother suffered from gastroenteritis 1 week ante partum . The newborn was treated with ampicillin, gentamicin and later amoxicillin but 5 months later was still a carrier of Salmonella . The possible route of infection and the guidelines for therapy and management of Salmonella infections during pregnancy and puerperium are discussed.

J Appl Microbiol, 1997 Aug, 83(2), 236 - 42
In vitro 14C-amino acid fermentation by CF3, a characterized continuous-flow competitive exclusion culture of caecal bacteria; Hume ME et al.; Competition for growth-limiting nutrients by broiler caecal bacteria and Salmonella has been suggested as one factor associated with decreased Salmonella caecal colonization . The amino acids arginine, aspartic acid, serine and threonine have been indicated as Salmonella growth-limiting nutrients . Broiler caecal bacteria maintained in a continuous-flow culture (CF3) were used as inoculum for media containing 14C-arginine, 14C-aspartic acid, 14C-serine or 14C-threonine . The 14C-labelled amino acids, except 14C-arginine, were metabolized to lactic, formic, acetic, propionic and butyric acids . In glucose-based media, 72%, 72% and 33% of the radiolabel from aspartic acid, serine and threonine, respectively, were detected in organic acids . Fermentation without glucose resulted in 48%, 50% and 71% of the radiolabel from aspartic acid, serine and threonine, respectively, being detected in organic acids . Results indicated that the early establishment of CF3 in young chicks may result in the depletion of growth-limiting amino acids and, therefore, reduction of Salmonella colonization.

Eur J Clin Invest, 1997 Aug, 27(8), 673 - 9
Comparative effects of nitric oxide synthesis inhibition and catecholamine treatment in a rat model of endotoxin shock; Nava E et al.; Catecholamines and volume repletion are currently used for the treatment of septic shock . However, the prognosis of patients suffering from this condition is very poor . An overproduction of nitric oxide (NO) seems to be related to the hypotension and tissue damage of endotoxin shock . Thus, treatment with NO synthase inhibitors has been proposed . Using a rat model of septic shock we have studied the effects of noradrenaline or the NO synthase inhibitor, NG-nitro-L-arginine methylester (L-NMMA) on arterial pressure, tissue damage and NO production . Anaesthetized rats treated with Salmonella typhosa showed a decrease in blood pressure accompanied by an increase in the plasma concentration of cytosolic enzymes (transaminases and lactate dehydrogenase, markers of cell disruption) and nitrite plus nitrate (NO2-/NO3-, markers of NO production) . A large proportion of these animals (40%) died before the end of the experiment . Co-treatment with noradrenaline resulted in temporary maintenance of arterial pressure followed by a decline, despite the dose being increased progressively . No differences were observed in plasma cytosolic enzymes, NO2-/NO3- or mortality compared with animals treated with lipopolysaccharide (LPS) alone . In contrast, administration of L-NMMA (10 mg kg-1) to septic animals prevented the fall in blood pressure and death caused by endotoxin . This treatment markedly diminished cell disruption, as measured by the plasma levels of necrosis enzymes, and partially, but significantly, reduced the production of NO as assessed by plasma NO2-/NO3- . We conclude that tissue damage in septic shock is related to the overproduction of NO and not exclusively to the hypotension that follows this increased production . Thus, maintenance of blood pressure with catecholamines fails to improve cellular damage . Instead, partial inhibition of NO generation is sufficient to ameliorate the haemodynamic and tissue-damaging effects of septic shock and improves survival in this model of endotoxaemia.

Microbiology, 1997 Aug, 143 ( Pt 8), 2665 - 72
Salmonella typhi mutants defective in anaerobic respiration are impaired in their ability to replicate within epithelial cells; Contreras I et al.; By using MudJ (Kan, lac)-directed operon fusion technology, mutants of Salmonella typhi whose gene expression is induced under anaerobic growth conditions were isolated . Characterization of their phenotypes and regulatory properties revealed that two of the mutants were unable to use nitrate as a terminal electron acceptor in the absence of oxygen, suggesting that they were defective in nitrate reductase activity . Anaerobic induction of these fusions did not further increase in response to nitrate . Strains carrying an additional mutation in oxrA were constructed . They showed a lower level of beta-galactosidase expression both aerobically and anaerobically; however, the ratios of anaerobic induction remained unaltered . These MudJ insertions mapped to the 17-19 min region of the chromosome . Based upon their phenotypes and mapping, one of the mutants probably possessed a modC (chlD)::MudJ insertion and the other a moaA (chlA)::MudJ insertion . A third mutant was unable to use either nitrate or fumarate as a terminal electron acceptor . All three mutants showed a reduced ability to enter into and proliferate within HEp-2 epithelial cells . The oxrA mutation enhanced entry and proliferation of both the wild-type cells and the three mutants . Taken together, these results suggest that anaerobic respiration plays a role in S . typhi invasiveness.

Trends Microbiol, 1997 Aug, 5(8), 318 - 22
The record of horizontal gene transfer in Salmonella; Baumler AJ; The evolution of virulence in Salmonella is driven by horizontal gene transfer . This has given rise to highly flexible pathogens that are able to colonize new niches and extend their host range . Tracing the record of horizontal gene transfer can provide clues to the virulence factors that contribute to the formation of new pathovars.

J Appl Physiol, 1997 Aug, 83(2), 359 - 65
Posthemorrhagic antipyresis: what stage of fever genesis is affected?
Romanovsky AA, Karman YK.
It has been shown that hemorrhage leads to a decreased thermal responsiveness to lipopolysaccharide (LPS) . The aim of this study was to clarify what stage of fever genesis {production of endogenous pyrogens such as interleukin-1 (IL-1), increase of the prostaglandin E2 (PGE2) concentration in brain tissue, activation of cold-defense effectors} is deficient in posthemorrhagic antipyresis . In adult rabbits, we evaluated the effect of acute hemorrhage (15 ml/kg) on the rectal temperature (Tre) responses to LPS from Salmonella typhi (200 ng/kg iv), ethanol-purified preparation of homologous IL-1 (1 ml from 3.5 x 10(7) cells, 1.5 ml/kg iv), and PGE2 (1 microg, intracisternal injection) . The effect of hemorrhage on Tre was also studied in afebrile rabbits, both at thermoneutrality (23 degrees C) and during ramp cooling (to 7 degrees C) . The hemorrhage strongly attenuated the biphasic LPS-induced fever (a Tre rise of 0.4 +/- 0.1 instead of 1.2 +/- 0.2 degrees C at the time of the second peak), the monophasic Tre response to IL-1 (by approximately 0.5 degrees C for over 1-5 h postinjection), and the PGE2-induced hyperthermia (0.4 +/- 0.1 vs . 0.9 +/- 0.1 degrees C, maxima) . In afebrile animals, the hemorrhage neither affected Tre at thermoneutrality nor changed the Tre response to cold exposure . The data suggest that neither insufficiency of cold-defense effectors nor lack of endogenous mediators of fever (IL-1, PGE2) can be the only or even the major cause of posthemorrhagic antipyresis . We speculate that fever genesis is altered at a stage occurring after the intrabrain PGE2 level is increased but before thermoeffectors are activated.

Pediatr Nephrol, 1997 Aug, 11(4), 488 - 90
Immune response to Escherichia coli O157:H7 in hemolytic uremic syndrome following salmonellosis; Flores FX et al.; Escherichia coli O157:H7, a Shiga-like toxin (SLT)-producing enteric pathogen, has been implicated in most cases of post-diarrheal hemolytic uremic syndrome (D + HUS) . Infection with other bacterial pathogens such as Salmonella has also preceded D + HUS episodes, leading to speculation that these organisms may also be etiological . We present two children with unrelated D + HUS following salmonellosis . Both children had negative stool cultures on sorbitol-MacConkey agar soon after the onset of diarrhea . After the diagnosis of HUS, both patients had repeat stool cultures positive for Salmonella alone . Polymerase chain reactions for SLT I and II gene sequences in Salmonella isolates were negative . Enzyme-linked immunosorbent assay for specific humoral response to E . coli O157:H7 lipopolysaccharide in acute and convalescent serum samples revealed evidence of heretofore undetected E . coli O157:H7 infection contemporaneous with each D + HUS episode . These cases demonstrate that isolation of only non-SLT-producing microbes from children with D + HUS should raise suspicion of concurrent undetected infection with SLT-producing organisms . Assaying specific immune response to E . coli O157:H7 can be an important epidemiological adjunct . Bacterial infection with non-SLT-producing Salmonella may represent concomitant enteric pathology rather than D + HUS-instigating infection.

Spine, 1997 Aug 1, 22(15), 1741 - 6
Spondylodiscitis . Clinical and magnetic resonance diagnosis; Maiuri F et al.; STUDY DESIGN: This study reviews 65 patients with spondylodiscitis, both spontaneous and postoperative and of different etiology, studied by magnetic resonance imaging . OBJECTIVES: To define the magnetic resonance imaging characteristics of infections of the spine in acute and chronic stages and to evaluate the role of magnetic resonance imaging in defining their etiology . BACKGROUND DATA: Early diagnosis of spondylodiscitis is often difficult because of the long latent period . Radiographs of the spine, bone scan, and computed tomography scan provide insufficient data . METHODS: Among 65 patients with spondylodiscitis studied by magnetic resonance imaging, 24 were examined in the acute stage (clinical evolution between 7 days and 20 days), and 41 were examined in the chronic stage (3-6 weeks) . The etiologic agent was staphylococcus in eight cases, Brucella in 13, Mycobacterium tuberculosis in 29, Salmonella in four, and unknown in 11 . RESULTS: In cases observed in the acute stage, the disc and the vertebral bodies were hypointense in T1 and hyperintense in T2; this relatively constant finding was not correlated with the etiologic agent . In the chronic stage, cases caused by Brucella or of unknown etiology showed long T1 and T2 relaxation times, with precocious contrast enhancement of the disc; in cases of tubercular etiology there was slight shortening of T1, with inhomogeneous enhancement of the involved vertebral bodies and late disc enhancement . CONCLUSIONS: Magnetic resonance imaging is the investigation method of choice in diagnosing spondylodiscitis, especially in very early stages of the disorder, when other investigations still yield negative results . In chronic stages, magnetic resonance imaging also allows tubercular spondylodiscitis to be distinguished from cases of different etiology.

Mutat Res, 1997 Aug, 387(1), 1 - 16
Review of mutagenicity of monocyclic aromatic amines: quantitative structure-activity relationships; Chung KT et al.; Monocyclic aromatic amines (MAAs) are environmental pollutants . Many of them are genotoxic and impose hazards to human health . The mutagenicity of more than 80 of these amines was reviewed with primary emphasis on evaluation by the Ames Salmonella/microsome testing system . Many amines are mutagenic in Salmonella tester strains TA98 and TA100, but S9 mix is required for activity for most of the active ones . 2,4-Diaminotoluene, 2,4-diaminoethylbenzene, and a few amines containing a nitro-group are direct mutagens . There are several quantitative structure-activity relationship (QSAR) models which rationalize mutagenicity of many aromatic amines and several parameters, such as the lowest unoccupied molecular orbital energy (ELUMO), highest occupied molecular orbital energy (EHOMO), and hydrophobicity that are important . What factors determine the minimum requirement for the compound to be mutagenic and what factors determine the extent of mutagenicity suggest questions for further study.

FEMS Microbiol Lett, 1997 Aug 1, 153(1), 33 - 42
SEF17 fimbriae are essential for the convoluted colonial morphology of Salmonella enteritidis; Allen-Vercoe E et al.; Salmonella enteritidis isolated from poultry infections generated a convoluted colonial morphology after 48 h growth on colonisation factor antigen (CFA) agar at 25 degrees C . A mutant S . enteritidis defective for the elaboration of the SEF17 fimbrial antigen, in which the agf gene cluster was inactivated by insertion of an ampicillin resistance gene cassette, and other wild-type S . enteritidis transduced to this genotype failed to produce convoluted colonies . However, growth of SEF17- mutants at 25 degrees C on CFA agar supplemented with 0.001% Congo red resulted in partial recovery of the phenotype . Immunoelectron microscopy demonstrated that copious amounts of the SEF17 fimbrial antigen were present in the extracellular matrix of convoluted colonies of wild-type virulent S . enteritidis isolates . Bacteria were often hyperflagellated also . Immunoelectron microscopy of SEF17- mutants grown on CFA agar+0.001% Congo red demonstrated the elaboration of an as yet undefined fimbrial structure . Isolates of S . enteritidis which were described previously as avirulent and sensitive to environmental stress failed to express SEF17 or produce convoluted colonies . These data indicate an essential role for SEF17, and possibly for another fimbria and flagella, in the generation of the convoluted colonial phenotype . The relationship between virulence and colonial phenotype is discussed.

Biomaterials, 1997 Aug, 18(16), 1115 - 20
Cytotoxic, allergic and genotoxic activity of a nickel-titanium alloy; Wever DJ et al.; The nearly equiatomic nickel-titanium (NiTi) alloy is known for its shape memory properties . These properties can be put to excellent use in various biomedical applications, such as wires for orthodontic tooth alignment and osteosynthesis staples . The aim of this study was to evaluate the short-term biological safety of the NiTi alloy . We carried out an end-point dilution minimal essential medium (MEM) extract cytotoxicity test, a guinea-pig sensitization test and two genotoxicity tests: the Salmonella reverse mutation test and the chromosomal aberration test . The NiTi alloy showed no cytotoxic, allergic or genotoxic activity, similar to the clinical reference control material AISI 316 LVM stainless steel . This promising biological behaviour was most likely due to a minimal release of ions and in that way a reflection of the good corrosion resistance of the NiTi alloy . Given these very good results, together with the good tissue compatibility as shown in several implantation studies in the literature, the NiTi alloy can be regarded as a biologically safe implant material with many promising clinical applications.

Infect Immun, 1997 Aug, 65(8), 3406 - 11
Expression profile and subcellular location of the plasmid-encoded virulence (Spv) proteins in wild-type Salmonella dublin; El-Gedaily A et al.; The plasmid-encoded virulence genes (spvABCD) in nontyphoid Salmonella strains mediate lethal infections in a variety of animals . Previous studies have shown that these genes are transcriptionally regulated by stationary-phase growth . We studied the expression profile and the subcellular locations of the SpvABCD proteins in wild-type S . dublin by using polyclonal antibodies against SpvA, SpvB, SpvC, and SpvD . The cellular levels of the individual proteins were determined during growth by quantitative immunoblotting . As expected, SpvA, SpvB, SpvC, and SpvD were not detectable before the late logarithmic growth phase and appeared in the sequence SpvA, SpvB, SpvC, and SpvD . In contrast to the transcriptional regulation, however, SpvA and SpvB reached their maximal expression shortly after induction and declined during further growth whereas SpvC and SpvD expression remained high throughout the stationary phase, indicating that the Spv proteins are individually regulated at a posttranscriptional level . To localize SpvABCD within the bacteria, the cells were fractionated into the periplasmic, cytoplasmic, inner membrane, and outer membrane components . The cell fractions and the culture supernatant were analyzed by immunoblotting . SpvA was present in the outer membrane, SpvB was present in the cytoplasm and the inner membrane, and SpvC was present in the cytoplasm . SpvD was secreted into the supernatant; however, a substantial portion of this protein was also detected in the cytoplasm and membranes . The molecular weights of SpvD in the supernatant and in the cytoplasm appeared to be equal, suggesting that SpvD is not cleaved upon secretion.

Infect Immun, 1997 Aug, 65(8), 3381 - 5
Safety and immunogenicity in humans of an attenuated Salmonella typhi vaccine vector strain expressing plasmid-encoded hepatitis B antigens stabilized by the Asd-balanced lethal vector system; Tacket CO et al.; Attenuated Salmonella typhi organisms which express genes encoding protective antigens of other pathogens have been developed for use as experimental oral vaccines . A delta asd S . typhi strain attenuated by deletions in cya, crp, and cdt which contains hepatitis B core (HBc) and pre-S genes encoded on an Asd+ pBR-based plasmid vector was constructed . Healthy adult volunteers ingested a single dose of 5 x 10(5) to 5 x 10(8) CFU of strain chi4073 (delta cya delta crp delta cdt S . typhi Ty2), 6 x 10(7) or 1 x 10(9) CFU of strain chi4632(pYA3149), a further derivative of chi4073 deleted in asd and containing the Asd+ vector without the HBc-pre-S fusion, or 3 x 10(7) or 7 x 10(8) CFU of strain X4632(pYA3167), a derivative containing the vector with the HBc-pre-S fusion . Chi4073 was generally well tolerated by 22 volunteers . No volunteer had fever or positive blood cultures; 4 of 22 volunteers shed vaccine organisms in the stool in the first 48 h only . Two of 18 volunteers who received one of the plasmid-containing derivatives of chi4073 developed low-grade fevers on day 10 or 12 after ingestion . One of these volunteers had positive blood cultures on days 7 and 8 . Seven of these 18 volunteers had vaccine organisms detected in their stools in the first 48 h only . Most volunteers developed S . typhi-specific serum responses and developed S . typhi-specific antibody-secreting cells . However, no volunteer developed serum antibody to hepatitis pre-S or pre-S-specific antibody-secreting cells . Although the parent strain chi4073 was well tolerated, induced immunoglobulin G seroconversion to S . typhi lipopolysaccharide in 80 to 100% of vaccinees and stimulated specific IgA-secreting lymphocytes in 80 to 100% of vaccinees given a single oral dose of 2 x 10(7) and 5 x 10(8) CFU, chi4073 derivatives containing the Asd+ vector with and without sequences encoding the HBc-pre-S fusion caused occasional febrile reactions at high doses and did not stimulate detectable immune responses to hepatitis B antigens.

Infect Immun, 1997 Aug, 65(8), 3186 - 92
Intracellular Salmonella dublin induces substantial secretion of the 40-kilodalton subunit of interleukin-12 (IL-12) but minimal secretion of IL-12 as a 70-kilodalton protein in murine macrophages; Bost KL et al.; The induction by intracellular pathogens of interleukin-12 (IL-12) secretion is of particular importance since this cytokine has been shown to be necessary for optimal cell-mediated immune responses . Several recent investigations have suggested that cultured macrophages are a significant source of IL-12 following intracellular infection with pathogens such as Salmonella spp . In an effort to critically evaluate the magnitude of the IL-12 response in cultured macrophages following interaction with Salmonella dublin, enzyme-linked immunosorbent assays specific for the 40- and 70-kDa subunits of IL-12 (IL-12p40 and IL-12p70) and a sensitive bioassay for IL-12p70 were used . Using BALB/c macrophages, S . dublin at various challenge doses was a potent inducer of IL-12p40 secretion (>6,000 pg/10(7) macrophages) . However when secretion of IL-12p70 was evaluated, S . dublin did not induce comparable IL-12p70 production (<80 pg/10(7) macrophages) at any time, despite varying the challenge dose of Salmonella . The limited ability of BALB/c (Ity(s)) macrophages to secrete IL-12p70 in response to Salmonella was not a strain-specific phenomenon since similar results were demonstrated for macrophages isolated from CBA/J (Ity(r)) and C3H/HeJ (lipopolysaccharide {LPS}-hyporesponsive) mice . While intracellular infection with Salmonella was not a potent stimulus for IL-12p70 secretion in these mouse strains, macrophages from these mice responded significantly to a stimulus of gamma interferon plus LPS . Taken together these results demonstrate a limited capacity for intracellular Salmonella to stimulate murine macrophage secretion of IL-12p70, despite being a significant stimulus for IL-12p40 secretion . Furthermore, our results suggest that Salmonella-induced IL-12p40 secretion by macrophages is not solely an LPS-mediated event.

J Mol Biol, 1997 Jul 25, 270(4), 616 - 23
Bioincorporation of telluromethionine into proteins: a promising new approach for X-ray structure analysis of proteins; Budisa N et al.; A simple and efficient method for the specific and quantitative replacement of the naturally occurring amino acid methionine by its isosteric analogue telluromethionine in the expression of recombinant proteins has been developed . The method requires a controlable and competitive expression system like the bacteriophage T7 polymerase/promoter in a methionine-auxotrophic host . Using methionine-auxotrophic Escherichia coli strains, incorporation of telluromethionine at high yields has been achieved for human recombinant annexin V, human mitochondrial transamidase, Arabidopsis glutathione-S-transferase and the N-terminal domain of Salmonella tailspike adhesion protein as confirmed by amino acid, mass-spectrometric and X-ray analyses . Expressed and purified telluromethionine-proteins and native proteins were found to crystallise isomorphously . In terms of efficient bio-expression, isomorphism of crystals and relative abundance of methionine residues, the production of telluromethionine-proteins as heavy-atom derivatives offers a valid and general approach in X-ray analysis by the method of multiple isomorphous replacement.

Vet Parasitol, 1997 Jul 15, 71(1), 1 - 15
The time course of the specific antibody response by various ELISAs in pigs experimentally infected with Toxoplasma gondii; Lind P et al.; With the aim of developing routine serological tests for monitoring the Toxoplasma infection status of Danish swine herds, four ELISAs based on tachyzoite antigen were set up: (1) an indirect ELISA for IgG-antibody; (2) a blocking ELISA for antibody to the membrane antigen, P30; (3) an indirect ELISA for IgM; (4) a reverse, antibody-catching IgM-ELISA . Groups of pigs (number between 6 and 10) were inoculated with tachyzoites of the RH-strain, tissue cysts of two complete strains, or oocysts in two doses (10(3) and 10(4) . All inoculations were tolerated well . Irrespective of strain and stage used for inoculation, specific IgG and anti-P30 blocking activity appeared after 1-2 weeks, with OD-values stabilizing after 3-6 weeks and persisting throughout the study period (3-4 months) . Specific IgM appeared quickly, but was short-lived (approximately 2 weeks) . A cut-off OD-value of 0.36 for positive seroreaction in the indirect IgG-ELISA was determined on the basis of 69 sera from four herds, investigated in the dye-test (serum dilution 1:10) and ELISA . The chosen cut-off gave optimal combined sensitivity and specificity of 0.94 and 0.92, respectively, using the dye-test as a standard . Corresponding figures for the blocking ELISA were 37% inhibition as cut-off, with sensitivity and specificity of 0.94 and 0.94, respectively . Sera from a total of 87 pigs, experimentally infected with bacteria of the genera Salmonella, Yersinia or Actinobacillus and with the parasites Isospora suis, Trichinella spiralis or Ascaris suum, in no case produced cross-reactions in the IgG-ELISA . However, 3/9 pigs inoculated with 50 000 sporocysts of Sarcocystis miescheriana gave maximal OD-readings of 0.40-0.45 during the 13-15 weeks observation period . None of the sera from heterologously infected animals produced inhibitions in the anti-P30 blocking ELISA exceeding 36%.

FEMS Microbiol Lett, 1997 Jul 15, 152(2), 255 - 60
A plasmid-mediated CMY-2 beta-lactamase from an Algerian clinical isolate of Salmonella senftenberg; Koeck JL et al.; Multiresistance to antibiotics including beta-lactams, e.g . cefoxitin, was transferred by conjugation to Escherichia coli strain C1a from a clinical isolate of Salmonella senftenberg recovered from stools of an Algerian child . The susceptibility pattern to beta-lactams was similar to the profile mediated by an AmpC-type beta-lactamase . By biochemical analysis, typical AmpC-type enzyme substrate and inhibition profiles were obtained . Finally, an ampC plasmid-encoded beta-lactamase gene was cloned and sequenced . Its deduced amino acid sequence confirmed its identity as a class C beta-lactamase . It showed 99.5% sequence identity with the plasmid-mediated beta-lactamase CMY-2 . The differences in the amino acid sequences of the two enzymes were located in the signal peptide.

Cell, 1997 Jul 11, 90(1), 55 - 64
A proteinaceous gene regulatory thermometer in Salmonella; Hurme R et al.; Novel utilization of the coiled-coil motif is presented that enables TlpA, an autoregulatory repressor protein in Salmonella, to sense temperature shifts directly and thereby to modulate the extent of transcription repression . Salmonella cells shifted to higher temperatures, such as those encountered at host entry, showed derepressed tlpA activity . tlpA::lacZ fusions indicated that the promoter itself is insensitive to thermal shifts and that transcription control was exerted by the autorepressor TlpA only . In vitro studies with highly purified TlpA showed concentration and temperature dependence for both fully folded conformation and function, indicating that the thermosensing in TlpA is based on monomer-to-coiled-coil equilibrium.

Emerg Infect Dis, 1997 Jul-Sep, 3(3), 395 - 400
Using laboratory-based surveillance data for prevention: an algorithm for detecting Salmonella outbreaks; Hutwagner LC et al.; By applying cumulative sums (CUSUM), a quality control method commonly used in manufacturing, we constructed a process for detecting unusual clusters among reported laboratory isolates of disease-causing organisms . We developed a computer algorithm based on minimal adjustments to the CUSUM method, which cumulates sums of the differences between frequencies of isolates and their expected means; we used the algorithm to identify outbreaks of Salmonella Enteritidis isolates reported in 1993 . By comparing these detected outbreaks with known reported outbreaks, we estimated the sensitivity, specificity, and false-positive rate of the method . Sensitivity by state in which the outbreak was reported was 0%(0/1) to 100% . Specificity was 64% to 100%, and the false-positive rate was 0 to 1.

Emerg Infect Dis, 1997 Jul-Sep, 3(3), 371 - 2
Emerging quinolone-resistant Salmonella in the United States; Herikstad H et al.; We conducted a national survey of antimicrobial resistance in human clinical isolates of Salmonella between July 1, 1994, and June 30, 1995 . Every tenth nontyphoidal Salmonella isolate received at state public health laboratories in the United States during this period was tested for resistance to 12 antimicrobial agents, including two quinolones, nalidixic acid, and ciprofloxacin . Emerging quinolone resistance was detected; of 4,008 isolates tested, 21 (0.5%) were resistant to nalidixic acid, and one (0.02%) was resistant to ciprofloxacin . Continued surveillance for quinolone-resistant Salmonella is necessary, particularly after the recent approval of a fluoroquinolone for use in animals intended for food in the United States.

Emerg Infect Dis, 1997 Jul-Sep, 3(3), 285 - 93
Emerging foodborne diseases; Altekruse SF et al.; The epidemiology of foodborne diseases is rapidly changing . Recently described pathogens, such as Escherichia coli O157:H7 and the epidemic strain of Salmonella serotype Typhimurium Definitive Type 104 (which is resistant to at least five antimicrobial drugs), have become important public health problems . Well-recognized pathogens, such as Salmonella serotype Enteritidis, have increased in prevalence or become associated with new vehicles . Emergence in foodborne diseases is driven by the same forces as emergence in other infectious diseases: changes in demographic characteristics, human behavior, industry, and technology; the shift toward a global economy; microbial adaptation; and the breakdown in the public health infrastructure . Addressing emerging foodborne diseases will require more sensitive and rapid surveillance, enhanced methods of laboratory identification and subtyping, and effective prevention and control.

FEMS Immunol Med Microbiol, 1997 Jul, 18(3), 185 - 92
Salmonella enterica var Typhimurium and Salmonella enterica var Enteritidis express type 1 fimbriae in the rat in vivo; Ewen SW et al.; In a series of experiments rats were dosed with purified type 1 fimbriae from Salmonella enterica var Enteritidis or with fimbriated cultures of either S . enterica var Typhimurium or S . enterica var Enteritidis . Paraffin-wax embedded histological sections of jejunal and ileal tissue were taken and stained by the streptavidin biotin complex (sABC) staining technique for the detection of salmonella and type 1 fimbriae . On oral infection with Enteritidis and Typhimurium both bacteria were shown to be closely associated with the rat ileal epithelium and expressed type 1 fimbriae, thus clearly demonstrating that type 1 fimbriae are expressed by salmonellae in vivo . Moreover, association with the ileum was also shown to occur when purified type 1 fimbriae were orally administered to rats . Our results suggest that type 1 fimbriae alone or in combination with other fimbriae may play an important role in the early stages of infection with these pathogenic bacteria.

FEMS Immunol Med Microbiol, 1997 Jul, 18(3), 139 - 45
R-form lipopolysaccharides (LPS) of Gram-negative bacteria as possible vaccine antigens; Stanislavsky ES et al.; The antigenic and immunogenic properties of R-form lipopolysaccharides (LPS) of Pseudomonas aeruginosa, Salmonella spp., Escherichia coli and Shigella spp . were studied . The results showed the presence of antigenic relationships among P . aeruginosa R mutants with different structures of the LPS core lipid A region and also among E . coli, Shigella and P . aeruginosa R-LPS, but not with S . minnesota Re-LPS . Vaccines prepared with R-LPS proved to be effective preparations for the active immunization of mice against P . aeruginosa infection . The vaccine stimulated 40-100% protection in mice depending upon the scheme of immunization.

New Microbiol, 1997 Jul, 20(3), 283 - 7
Use of hybridization assay and direct immuno assay for detection of Salmonella spp . in surface waters and a comparison with conventional culture procedure; Marranzano M et al.; Hybridization assay and direct immunoassay for detecting Salmonella in contaminated surface waters have been compared with the conventional culture procedure . The 67 samples examined were taken from different rivers in the provinces of Catania and Ragusa . By culture method, Salmonella was isolated in 23 samples (34%), while direct immunoassay revealed the presence of Salmonella in 58 samples (87%) and the hybridization method identified Salmonella in 20 samples (30%) . On the basis of the results obtained, the direct immunoassay method proved to be inaccurate for the high number of false positives revealed . The DNA probe test gave almost identical results to those obtained with the culture method, with notably shorter execution times than the latter . This test proved to be both sensitive and specific and could be used for the direct demonstration of Salmonella in surface waters where it is easier to find bacteria under stress from the environmental conditions, in waters where isolation is difficult, and in all those environmental control conditions which do not require isolation and the serological typing of the strains of Salmonella.

J Antimicrob Chemother, 1997 Jul, 40(1), 67 - 75
Antimicrobial resistance in Salmonella enterica subsp . enterica serovar typhimurium from humans and production animals; Seyfarth AM et al.; We have studied the frequency of antimicrobial resistance and epidemiological relatedness among 473 isolates of Salmonella enterica subsp . enterica serovar typhimurium (S . typhimurium) from human and veterinary sources . The human strains were clinical isolates from patients with diarrhoea sent to the State Serum Institute during August 1993 (228 isolates) . The animal strains were isolated from clinical or subclinical infections in cattle (48 isolates), pigs (99 isolates) or poultry (98 isolates), all from 1993 . All strains were tested against 22 different antimicrobial agents used in both human and veterinary medicine with the tablet diffusion method . Strains were also phage-typed and the plasmid content determined in all resistant strains . Ribotyping was performed on selected strains . Of 228 human isolates tested, 19.3% of the strains were resistant to one or more antimicrobial agent compared with 10.4% of strains from cattle, 11.1% of strains from pigs and 9.2% of strains from poultry . Multiple resistance, i.e . resistance against at least four antimicrobial agents, was found in 9.2% of the human strains, but in only two of the cattle isolates . The majority of the multi-resistant strains in humans were from infections contracted outside Denmark, most often in southern Europe or south-east Asia . Resistance in human strains was most common against tetracycline (13%), ampicillin (12%), sulphonamide (12%), streptomycin (10%) and chloramphenicol (8%) . The resistance pattern differed somewhat in animal isolates: Poultry strains were usually resistant only to ampicillin, while pig and cattle isolates were most often resistant to sulphonamide, tetracycline and streptomycin . Typing of the strains showed that some animal strains and human strains were indistinguishable . In conclusion, while antimicrobial resistance was present in S . typhimurium isolated from humans and animals in Denmark, multiple resistance was most often acquired outside Denmark.

Indian J Gastroenterol, 1997 Jul, 16(3), 115 - 6
Hepatitis E virus and Salmonella paratyphi A coinfection; Phadke AY et al.; We report a patient with simultaneous Salmonella paratyphi A and hepatitis E virus infection . The possibility of coinfection with water borne diseases in India is emphasized.

Lett Appl Microbiol, 1997 Jul, 25(1), 54 - 7
Subspecies differentiation of Salmonella by PCR-RFLP of the ribosomal operon using universal primers; Shah SA et al.; A polymerase chain reaction (PCR)-based method was developed to aid identification of bacteria to subspecies level . The method used primers that annealed to highly conserved regions of the bacterial rRNA operon, which are proposed to be universal for all bacteria . The resulting PCR products gave unique electrophoretic patterns due to restriction fragment length polymorphisms (RFLP) within the rRNA operon, allowing differentiation to the subspecies level . Six serotypes of Salmonella choleraesuis are presented to demonstrate the specificity of PCR-RFLP patterns for building an identification database . As the database continues to accumulate, the method proves to be specific and rapid for identifying bacteria based on stable genetic characteristics.

Can J Vet Res, 1997 Jul, 61(3), 173 - 81
Utilization of both phenotypic and molecular analyses to investigate an outbreak of multidrug-resistant Salmonella anatum in horses; Hartmann FA et al.; Phenotypic and molecular techniques, including antimicrobial susceptibility testing, plasmid analysis, and pulsed-field gel electrophoresis (PFGE) were used to characterize 15 isolates of multidrug-resistant (MDR) Salmonella anatum cultured during a 16 mo period from horses and a veterinary clinic environment . The isolates were resistant to multiple antimicrobial agents and could be placed into 4 groups based on their antimicrobial resistance patterns . The isolates contained multiple plasmids ranging in size from 2 to > 100 kb that could be grouped into 3 different plasmid profile patterns; these patterns did not correlate with the antimicrobial resistance groupings . Furthermore, antimicrobial resistance was conjugatively transferable . Digestion of genomic DNA from the 15 isolates with 3 different restriction endonucleases, SfiI, SpeI, and XbaI followed by PFGE revealed a highly conserved restriction endonuclease digestion pattern . In contrast, diverse banding patterns were observed with S . anatum obtained from other sources . These observations suggest that the MDR S . anatum isolates represent a common outbreak strain even though they possess different, albeit similar, antibiograms and plasmid profiles . The study showed that PFGE is a useful epidemiological tool for discriminating between unrelated and outbreak-related strains of S . anatum . In conclusion, epidemiological studies of outbreaks caused by MDR isolates of S . anatum should consist of both genotypic and phenotypic methods of analysis.

Am J Surg, 1997 Jul, 174(1), 87 - 93
Splenic abscesses from 1987 to 1995; Ooi LL et al.; BACKGROUND: Isolated splenic abscesses is an uncommon clinical entity that is being increasingly recognized as a cause of intraabdominal sepsis in a wide variety of clinical situations, and involving a wide range of organisms . The increasing incidence of immunosuppressed states in this decade due to the use of chemotherapy for oncology, immunosuppression therapy for transplantation, and acquired immune deficiency syndrome, has changed the disease pattern of splenic abscesses . METHOD: Data from 287 cases reported in the English literature between 1987 and 1995 were collected, analyzed, and compared with two previous reviews of cases reported before 1987 . RESULTS: Staphylococcus, Salmonella, and Escherichia coli are the most common organisms cultured . Immunosuppressed states were present in 33.5% of cases, with intravenous drug abuse and acquired immune deficiency syndrome accounting for half these cases . Computerized tomography and ultrasonography are diagnostic, with a sensitivity of 92.2% and 87.2%, respectively . Nonoperative management has a success rate of less than 65%, but salvage splenectomy does not increase mortality compared with splenectomy as initial therapy . CONCLUSIONS: Splenic abscesses are increasingly recognized with immunosuppressed states . Percutaneous radiologically guided drainage may be suitable in some cases, but splenectomy with appropriate antibiotics is the definitive treatment.

Mutagenesis, 1997 Jul, 12(4), 215 - 20
Aniline and its metabolites generate free radicals in yeast; Brennan RJ et al.; The carcinogen aniline is negative in the Ames Salmonella mutagenicity assay . Aniline does, however, induce intrachromosomal recombination between repeated sequences in Saccharomyces cerevisiae, resulting in deletion (DEL) of intervening sequences . We have investigated whether the generation of oxidative free radical species by aniline and/ or its metabolites may be responsible for its recombinagenic activity in yeast . The toxicity and recombinagenicity of aniline in yeast were greatly reduced in the presence of the free radical scavenger N-acetyl cysteine . Aniline cytotoxicity was many-fold increased in strains of S.cerevisiae lacking the antioxidant enzyme superoxide dismutase . Aniline also induced oxidation of the intracellular free radical-sensitive reporter compound 2,4-dichlorofluorescin diacetate to its fluorescent derivative 2,4-dichlorofluorescein in vivo in S.cerevisiae . The aniline metabolites 4-aminophenol and 2-aminophenol were significantly more potent inducers of DEL recombination in yeast than aniline . In contrast, the secondary metabolite 4-acetamidophenol (acetaminophen) was non-toxic and non-recombinagenic in yeast . 4-Aminophenol and 2-aminophenol were also significantly more toxic than aniline in a superoxide dismutase deficient yeast strain . 4-aminophenol was a significantly more potent oxidizer of 2,4-dichlorofluorescin diacetate than aniline . The Escherichia coli soxS promoter, which is induced in the presence of redox cycling agents like paraquat, was induced weakly by aniline at toxic doses . The soxS promoter was strongly induced by 4-aminophenol and 2-aminophenol . The results indicate a role for oxidative stress, mediated by generation of superoxide radical, in the toxicity and recombinagenicity of aniline . The increased activity of 4-aminophenol and 2-aminophenol suggests that ring hydroxylation may be an important activating step in this process.

Ann Vasc Surg, 1997 Jul, 11(4), 416 - 9
Ruptured Salmonella mycotic aneurysm of the extracranial carotid artery; Rice HE et al.; Mycotic aneurysms of the extracranial carotid artery are rare and difficult to diagnose and can lead to significant medical morbidity . Treatment of these lesions requires expert surgical management and necessitates an assiduous search for an underlying source . We report a case of a ruptured mycotic aneurysm of the cervical carotid artery due to Salmonella infection successfully treated by wide excision and saphenous vein patch angioplasty.

J Med Microbiol, 1997 Jul, 46(7), 623 - 8
Analysis of the mechanism of quinolone resistance in nalidixic acid-resistant clinical isolates of Salmonella serotype Typhimurium; Ruiz J et al.; Over a period of 2.5 years, 42 cases of gastro-enteritis caused by nalidixic acid-resistant Salmonella serotype Typhimurium occurred in Malaga . The epidemiological relationship among the strains involved was investigated by analysis of plasmid profile and of chromosomal DNA by pulsed-field gel electrophoresis (PFGE) . Despite having different plasmid profiles, all 42 nalidixic-acid resistant Typhimurium isolates had evolved from one clone as shown by analysis of chromosomal DNA by PFGE . The mechanism of quinolone resistance in these Typhimurium isolates was also investigated . Analysis of outer-membrane proteins and lipopolysaccharide from quinolone-susceptible and resistant clinical isolates tested showed no differences . All nalidixic acid-resistant isolates had MICs for ciprofloxacin of 0.25 mg/L and for nalidixic acid of 1024 mg/L . Polymerase chain reaction fragments of 285 bp, containing the quinolone resistance-determining region of the gyrA gene, and of 237 bp, containing the region of parC homologous to the quinolone resistance-determining region of the gyrA gene, were sequenced . All resistant isolates presented a change at Ser-83 to Phe in the GyrA protein, but no changes were observed in the ParC protein . These findings indicated that this mutation in gyrA plays a major role in the acquisition of nalidixic-acid resistance in clinical isolates of Typhimurium.

J Med Microbiol, 1997 Jul, 46(7), 617 - 22
Phenotypic and genotypic discrimination of strains of Salmonella serotype Eimsbuettel from human and animal sources; Old DC et al.; One hundred isolates of Salmonella serotype Eimsbuettel from various human, animal and environmental sources in six countries were typed and shown to belong to five ribotypes, five biotypes and eight different ribotype/biotype groups, one of which, ribotype 3/biotype 5, was represented among isolates from all six countries . Most of the Eimsbuettel isolates from Scotland belonged to ribotype 1/biotype 3, which was the epidemic strain involved in a large outbreak centred in a Glasgow maternity hospital in 1986 . That strain was also responsible for almost all the human infections that occurred in the west of Scotland in the years of this study . However, isolates from human cases in the east of Scotland belonged to either ribotype 2/biotype 1 or ribotype 3/biotype 5, groups not found in the west of Scotland . Representatives of all three ribotype/biotype groups causing human infection in Scotland were also found among isolates from poultry or poultry-associated materials . Plasmids were carried by only 14% of isolates and so provided little additional strain discrimination . However, plasmid analysis suggested that Salmonella Eimsbuettel of ribotype 2/biotype 1 had the potential to enter the human food chain in the UK via meat or bone meal, animal feed and poultry.

Crit Care Med, 1997 Jul, 25(7), 1198 - 206
Dietary fish oil and fish and borage oil suppress intrapulmonary proinflammatory eicosanoid biosynthesis and attenuate pulmonary neutrophil accumulation in endotoxic rats; Mancuso P et al.; OBJECTIVE: Proinflammatory eicosanoids and cytokines are important mediators of local inflammation in acute lung injury . We determined if enteral nutrition with anti-inflammatory fatty acids, eicosapentaenoic acid, and gamma-linolenic acid would reduce the intrapulmonary synthesis of proinflammatory eicosanoids and cytokines and pulmonary neutrophil accumulation in a rat model of acute lung injury . DESIGN: Prospective, randomized, controlled, double-blind study . SETTING: Research laboratory at a university medical center . SUBJECTS: Male Long-Evans rats (250 g) . INTERVENTIONS: Rats were randomly assigned to three dietary treatment groups and fed nutritionally complete diets (300 kcal/kg/day) containing 55.2% of the total calories from fat with either 97% corn oil, 20% fish oil, or 20% fish and 20% borage oil for 21 days . On day 22, bronchoalveolar lavage was performed 2 hrs after an intravenous injection of Salmonella enteritidis endotoxin (10 mg/kg) or saline . Bronchoalveolar lavage fluid was analyzed for leukotriene B4, leukotriene C4/D4, thromboxane B2, prostaglandin E2, 6 keto-prostaglandin F1alpha, tumor necrosis factor (TNF)-alpha, and macrophage inflammatory protein-2 (MIP-2) . Lung myeloperoxidase activity (a marker for neutrophil accumulation) and phospholipid fatty acid composition were also determined . MEASUREMENTS AND MAIN RESULTS: Lung phospholipid concentrations of arachidonic acid were lower and the concentrations of eicosapentaenoic acid and docosahexaenoic acid were higher with fish oil and fish and borage oil as compared with corn oil . Dihomo-gamma-linolenic acid, the desaturated and elongated intermediate of gamma-linolenic acid, increased with fish and borage oil as compared with fish oil and corn oil . The levels of leukotriene B4, leukotriene C4/D4, 6-keto-prostaglandin F1alpha, and thromboxane B2 with corn oil were significantly increased with endotoxin as compared with saline . In contrast to the corn oil group, endotoxin did not significantly increase bronchoalveolar lavage levels of leukotriene B4, leukotriene C4/D4, and thromboxane B2 above those of saline-treated rats with fish oil and fish and borage oil . Lung myeloperoxidase activity was significantly increased in endotoxin-treated rats compared with those rats given saline in all dietary treatment groups . However, lung myeloperoxidase activity was significantly lower with either fish oil or fish and borage oil as compared with corn oil after endotoxin . Although endotoxin increased the levels of TNF-alpha and MIP-2 with all dietary treatment groups as compared with saline-treated rats, there were no significant differences in the levels of either cytokine between the dietary treatment groups . CONCLUSIONS: These results indicate that dietary fish oil and fish and borage oil as compared with corn oil may ameliorate endotoxin-induced acute lung injury by suppressing the levels of proinflammatory eicosanoids (but not TNF-alpha or MIP-2) in bronchoalveolar lavage fluid and reducing pulmonary neutrophil accumulation.

Infect Immun, 1997 Jul, 65(7), 2983 - 6
Induction and characterization of heat shock proteins of Salmonella typhi and their reactivity with sera from patients with typhoid fever; Tang SW et al.; The heat shock protein (HSP) response of Salmonella typhi following exposure to elevated growth temperatures was studied . Three major proteins with molecular sizes of 58, 68, and 88 kDa were abundantly expressed when S . typhi cells were shifted from 37 to 45 degrees C and to 55 degrees C . These proteins were also constitutively expressed at 37 degrees C . Western blotting and immunoprecipitation studies with anti-HSP monoclonal antibodies revealed that the 58- and 68-kDa proteins were analogous to the GroEL and DnaK proteins, respectively, of Escherichia coli . These HSPs are also abundantly present in the outer membrane fraction of disrupted cells and, to a lesser extent, in the cytosol . Immunoblotting experiments with sera from patients with a culture-positive diagnosis of typhoid fever showed the presence of antibodies to these HSPs . Nine of twelve sera reacted with the 58-, 68-, and 88-kDa proteins, while three sera reacted only with the 68- and 88-kDa proteins . All 10 sera from healthy individuals showed no binding to these HSPs . In light of the well-documented roles of HSPs in the pathogenesis of microbial infections and as immunodominant antigens, these findings may be relevant for a better understanding of disease processes and for the future development of diagnostic and preventive strategies.

Int J Food Microbiol, 1997 Jun 17, 37(1), 55 - 62
Detection of Salmonella from raw food samples using Dynabeads anti-Salmonella and a conventional reference method; Cudjoe KS et al.; A Dynal core method has been established using Dynabeads anti-Salmonella to detect Salmonella from all categories of food samples . The protocol consists of the standard pre-enrichment of samples in buffered peptone water followed by immunomagnetic separation and subsequent selective enrichment of the bead-bacteria complexes in Rappaport-Vassiliadis Soya Peptone broth before plating onto Salmonella selective media . This modified IMS cultural method is intended to replace or augment traditional cultural methods used for Salmonella detection due to its specificity and increased sensitivity . The optional direct plating of bead-bacteria complexes onto solid media using a swab-streak technique is suitable for processed foods or samples known to have a history of very low resident flora . In an evaluation using 100 naturally contaminated samples, this IMS core method detected 39 of the 44 positive samples detected by all the methods combined, compared to 31 detected by the conventional ISO 6579 reference method . Furthermore, in ten different food matrices inoculated with low levels (1-5 cells/25 g) of twenty Salmonella serovariants, frozen for one month before being examined, the IMS core method, showed a 90% concordance with the ISO method and isolated two more Salmonella positive samples than the conventional ISO method.

J Immunol, 1997 Jun 15, 158(12), 5941 - 8
Transcriptional activation of vascular cell adhesion molecule-1 gene in vivo and its role in the pathophysiology of neutrophil-induced liver injury in murine endotoxin shock; Essani NA et al.; Polymorphonuclear leukocytes (neutrophils) can cause hepatic parenchymal cell injury during endotoxin (ET) shock . Because adhesion molecules are critical for inflammatory cell damage, the role of vascular cell adhesion molecule-1 (VCAM-1) was studied in the pathophysiology of ET shock . ET-sensitive mice (C3Heb/FeJ) were treated with 700 mg/kg galactosamine in combination with 100 microg/kg Salmonella abortus equi ET, 15 microg/kg TNF-alpha, or 13 to 23 microg/kg IL-1 . VCAM-1 mRNA formation was strongly activated in animals treated with ET, TNF-alpha, or IL-1 . In contrast, only TNF-alpha and IL-1, not ET, induced VCAM-1 gene transcription in livers of ET-resistant mice (C3H/HeJ) . Immunohistochemistry and isolation of liver cells during endotoxemia indicated that VCAM-1 mRNA and protein were only formed in endothelial cells and Kupffer cells, not in hepatocytes . Galactosamine/ET induced neutrophil accumulation in sinusoids (515 +/- 30 neutrophils/50 high power fields) followed by transmigration at 7 h . At that time, severe liver injury was observed (necrosis, 53 +/- 5%) . An anti-VCAM-1 Ab (3 mg/kg) attenuated the area of necrosis by 60% . The Ab reduced neutrophil transmigration by 84%, but had no effect on the total number of cells in the liver vasculature . Flow cytometric analysis identified the presence of very late Ag-4 on mouse peripheral neutrophils . Our data demonstrated cytokine-dependent VCAM-1 gene transcription and protein expression in the liver during endotoxemia . Neutrophils were able to use very late Ag-4/VCAM-1 interactions to transmigrate into liver parenchyma in vivo . Preventing transmigration by blocking VCAM-1 protected hepatocytes against neutrophil-induced injury.

Mutat Res, 1997 Jun 13, 391(1-2), 71 - 7
Exposure of organic extracts of air particulates to sunlight leads to metabolic activation independence for mutagenicity; al-Khodairy F et al.; Air particulates were collected on Whatman, GFA glass fibre filters using a RADECO constant-flow air sampler from a car-parking basement and an open roadside adjacent to the basement . While the basement was not exposed to sunlight, the roadside from where air samples were collected was exposed to regular daylight in the month of July (peak summer month) . The filters were soaked and sonicated in acetone to dislodge the particulates and then a residue was obtained after evaporation of acetone . The residues were either held in dark or exposed to natural sunlight or germicidal UV light before being tested for mutagenicity using the Salmonella tester strain TA98 with and without metabolic activation (S9 mix) . The results showed that the addition of S9 mix resulted in only a slight increase in the frequency of histidine revertants/plate in the case of daylight-exposed roadside air samples . On the other hand, a considerable increase in mutagenicity was observed in the case of the basement air samples, particularly at higher concentrations of the organic extracts when S9 mix was added . However, a pre-exposure of the organic extract of air from the basement to sunlight abrogated the need for S9 mix for showing mutagenic activity . A pre-exposure of the same extracts to germicidal UV light failed to produce a similar effect . These results suggested that long wavelengths of natural sunlight could be responsible for the conversion of certain promutagens in air particulates into direct-acting mutagens . The environmental impact of solar radiation as a modifier of air particulate mutagens in high-sun countries like Saudi Arabia needs to be carefully considered for assessment of air pollution-related health risks.

Mutat Res, 1997 Jun 13, 391(1-2), 33 - 8
Comparison of the lethal effects of different actinomycins on a repair-deficient strain of Escherichia coli; Holmalahti J et al.; We report here the isolation and purification of a genotoxic antibiotic from the culture medium of a Streptomyces strain . The antibiotic was identified as actinomycin X2 by using a database search (AntiBase) . In the previous studies a related compound, actinomycin D, has been shown to be non-mutagenic in the salmonella/microsome assay and several other bacterial systems . The fact that an actinomycin was detected by a bacterial repair assay seems to contradict these results . Therefore we tested several actinomycins by differential killing assay based on the same Escherichia coli strains that were used in our screening bioassays . According to our results the uvrA, recA double mutant sensitizes E . coli to the genotoxic effects of actinomycins.

Carbohydr Res, 1997 Jun 11, 301(1-2), 61 - 7
Structure of the O-specific polysaccharide of Salmonella enterica ssp . arizonae O50 (Arizona 9a,9b); Senchenkova SN et al.; On the basis of sugar and methylation analysis, selective removal of 3,6-dideoxy-L-xylohexose (colitose, Col), 1H and 13C NMR spectroscopy, including 1D NOE, 2D COSY, and 2D H-detected 1H, 13C heteronuclear multiple-quantum coherence (HMQC), the following structure of the repeating unit of the O-specific polysaccharide of Salmonella enterica ssp . arizonae O50 (Arizona 9a,9b) was established: {sequence: see text} The O-antigen studied includes a trisaccharide fragment alpha-Co1p-(1-->2)-beta-D-Galp-(1-->3)-beta-D-GlcpNAc, which is a colitose ('3-deoxy-L-fucose') analogue of the Lewis (precursor) blood group antigen.

Gene, 1997 Jun 11, 192(1), 51 - 9
The invasion-associated type-III protein secretion system in Salmonella--a review; Collazo CM et al.; The genetic determinants that confer upon Salmonella the ability to enter non-phagocytic cells are largely encoded in a pathogenicity island located at centisome 63 of the bacterial chromosome . Molecular genetic analysis has revealed that this region encodes a specialized protein secretion system that mediates the export and/or translocation of putative signaling proteins into the host cell . This protein secretion system, which has been termed type III or contact-dependent, has also been identified in other plant and animal pathogens that have, in common, the ability to interact with eukaryotic host cells in an intimate manner.

J Investig Med, 1997 Jun, 45(5), 295 - 301
A novel model of bacterially-induced acute anterior uveitis in rats and the lack of effect from HLA-B27 expression; Baggia S et al.; BACKGROUND: Humans with the major histocompatibility antigen B27 (HLA-B27) are especially at risk for developing rheumatic disorders such as ankylosing spondylitis and Reiter's syndrome . Acute anterior uveitis (AAU) often occurs in association with these diseases or in HLA B27 positive individuals without joint disease . METHODS: We induced acute anterior uveitis in Lewis rats by a standard model, the intraperitoneal injection of 200 micrograms of Escherichia coli endotoxin . We also developed a novel model of uveitis secondary to gram-negative infection . RESULTS: Transgenic rats that expressed a low copy number of the B27 gene did not differ statistically from litter mate controls in the intensity of anterior uveitis as judged by histology, enumeration of cells in aqueous humor, protein in aqueous humor, or slit lamp examination . The majority of rats exposed to live Salmonella enteritidis or Yersinia enterocolitica 0:3 using either an oral or intravenous route of infection developed anterior uveitis . In contrast to the disease induced by endotoxin that is most intense 24 hours after the endotoxin challenge, uveitis induced by live bacteria usually began 7 to 9 days after exposure to bacterial products, was more often unilateral, persisted for as long as 3 weeks, and was sometimes recurrent . The expression of HLA-B27 did not appear to influence the incidence or severity of uveitis in B27+ low copy heterozygous animals . CONCLUSION: This rat model of AAU should facilitate evaluation of bacterial antigenic component(s) involved in the pathogenesis of live gram-negative bacteria induced AAU.

Zentralbl Bakteriol, 1997 Jun, 286(1), 69 - 82
Further search for virulence factors encoded by Salmonella serovar-specific plasmids; Glockner S et al.; The so called Salmonella virulence plasmids which are specifically prevalent among some of the S . enterica serovars were shown to contribute only marginally to the virulence make-up of salmonella, which is in contrast to Shigella and Yersinia spp . The experiments reported in this paper failed to find encoded plasmid factors which contribute to serum resistance, surface antigens, immunoinsufficiency or to up-regulation of chromosomally encoded factors such as toxins, surface antigens etc . Taking into consideration the rare prevalence of these plasmids among S . enterica but their common occurrence among a few of its serovars, their virulence implication remains an enigma.

Zentralbl Bakteriol, 1997 Jun, 286(1), 23 - 32
Screening for Salmonella with a murine monoclonal antibody M105 detects both Felix O1 bacteriophage sensitive and resistant Salmonella strains; Tsang RS et al.; Ten Felix O1 (FO1) bacteriophage sensitive Salmonella strains as well as their phage resistant derivates together with 39 strains of FO1-resistant Salmonella were tested for their reactivities with a murine monoclonal antibody, M105, by indirect whole cell and competitive ELISA . All FO1 phage sensitive and 48 of the 49 FO1-resistant Salmonella strains were found to react with M105 . The single Salmonella strain not reacting with M105 was a FO1 resistant derivative selected by exposing the sensitive parent strain to the phage . This M105-negative and FO1-resistant strain was also found to be a rough mutant without O-antigens and possibly lacks the terminal LPS core sugars which form the M105 reactive epitope.

Pharmacol Toxicol, 1997 Jun, 80(6), 272 - 9
T25: a simplified carcinogenic potency index: description of the system and study of correlations between carcinogenic potency and species/site specificity and mutagenicity; Dybing E et al.; A simplified carcinogenic potency index, the T25, is proposed as a practical method for the inclusion of potency considerations in carcinogen classification systems . The T25 is the chronic daily dose in mg per kg bodyweight which will give 25% of the animals tumours at a specific tissue site, after correction for spontaneous incidence, within the standard life span of that species . Calculated T25 values of a set of 113 US National Cancer Institute/National Toxicology Program (NC/NTP) carcinogens showed excellent correlation (correlation coefficient 0.96, P < 0.0001) with the carcinogenic potency index TD50 of Peto et al . (1984) . The mean of T25 values for 51 transspecies, multiple common site NCI/NTP carcinogens were 10-fold lower than those for 62 NCI/NTP single species, single site carcinogens . For these 113 carcinogens, the mean T25 values were approximately 3-fold lower for agents that were also mutagenic in Salmonella compared to the non-mutagenic agents.

Mol Microbiol, 1997 Jun, 24(6), 1235 - 47
Role of arginine-43 and arginine-69 of the Hin recombinase catalytic domain in the binding of Hin to the hix DNA recombination sites; Adams CW et al.; The Hin recombinase mediates the site-specific inversion of a segment of the Salmonella chromosome between two flanking 26bp hix DNA recombination sites . Mutations in two amino acid residues, R43 and R69 of the catalytic domain of the Hin recombinase, were identified that can compensate for loss of binding resulting from elimination of certain major and minor groove contacts within the hix recombination sites . With one exception, the R43 and R69 mutants were also able to bind a hix sequence with an additional 4bp added to the centre of the site, unlike wild-type Hin . Purified Hin mutants R43H and R69C had both partial cleavage and inversion activities in vitro while mutants R43L, R43C, R69S, and R69P had no detectable cleavage and inversion activities . These data support a model in which the catalytic domain plays a role in DNA-binding specificity, and suggest that the arginine residues at positions 43 and 69 function to position the Hin recombinase on the DNA for a step in the recombination reaction which occurs either at and/or prior to DNA cleavage.

J Hosp Infect, 1997 Jun, 36(2), 123 - 31
Application of molecular methods to a nosocomial outbreak of Salmonella enteritidis phage type 4; Rushdy AA et al.; A nosocomial outbreak of Salmonella enteritidis phage type 4 occurred in July 1995 . Seven definite cases were identified over 13 days affecting four wards in a London hospital . The outbreak strain was characterized by plasmid profile typing and pulsed-field gel electrophoresis (PFGE), and was unusual in that it did not possess a 38 MDa plasmid common to most isolates of S . enteritidis PT 4 made from humans and food animals in England and Wales . Seven asymptomatic excreters were identified on screening . No additional cases occurred on wards after standard isolation procedures were implemented . No common or continuing food or dietary source was identified . Results of epidemiological, microbiological and environmental investigations suggested that the outbreak was due to person-to-person transmission within the hospital . The source of the outbreak was not established but was probably due to admission of a patient with an unrecognized infection of S . enteritidis PT 4 . The study highlights the importance of close collaboration between hospital staff, epidemiologists and microbiologists, and demonstrates the value of molecular techniques for strain subdivision in outbreak investigations.

Eur J Immunol, 1997 Jun, 27(6), 1331 - 8
HLA-B27 modulates intracellular survival of Salmonella enteritidis in human monocytic cells; Laitio P et al.; Human major histocompatibility complex class I allele HLA-B27 is associated with a group of diseases called spondyloarthropathies . In reactive arthritis (ReA), the disease is triggered by certain infections, e.g . gastroenteritis caused by Salmonella . The host/microbe interaction is abnormal in susceptible individuals leading to inefficient elimination of arthritis-triggering bacteria, fragments of them, or both, after the initial infection . Using transfected human monocytic U937 cell lines, we demonstrate that the expression of the HLA-B27 antigen does not influence the uptake of S . enteritidis into U937 cells in vitro . Interestingly, HLA-B27 remarkably impairs the elimination of S . enteritidis within the HLA-B27 transfected U937 cells . The impaired elimination of ReA-triggering microbes by HLA-B27+ monocytes may offer an explanation for the persistence of ReA-triggering microbes in susceptible HLA-B27+ individuals . This modulation of the host/microbe interaction by HLA-B27 may have an important role in the pathogenesis of ReA.

Lett Appl Microbiol, 1997 Jun, 24(6), 493 - 7
Immunomagnetic separation and conventional culture procedure for detection of naturally occurring Salmonella in raw pork sausages and chicken meat; Ripabelli G et al.; The aim of the study was to compare immunomagnetic separation (IMS) and conventional selective enrichment procedures using selenite cystine broth (SC) and Rappaport-Vassiliadis broth (RV) in 137 naturally contaminated food samples (69 raw pork sausages and 68 chicken meat) . The utilization of SC or IMS appeared to be the most appropriate enrichment procedure: 15 out of 18 Salmonella-positive samples (83.3%) were detected by SC and 12 (66.7%) by IMS; RV yielded only seven positive isolations (38.9%) . However, RV yielded the highest count of Salmonella colonies per plate and the lowest interference by competing organisms . IMS could become a reliable alternative to standard enrichment procedures and a combined IMS and selective enrichment broth could increase the chance of Salmonella recovery.

Crit Care Med, 1997 Jun, 25(6), 1030 - 6
Monoclonal antibody to endotoxin attenuates hemorrhage-induced lung injury and mortality in rats; Bahrami S et al.; OBJECTIVES: To determine the possible role of enteric bacteria-derived endotoxin in the pathogenesis of the lung injury and mortality in rats following hemorrhagic shock and resuscitation . DESIGN: Prospective, randomized study . SETTING: Animal laboratory of an institute for research traumatology . SUBJECTS: Male Sprague-Dawley rats, weighing 450 to 480 g . INTERVENTIONS: Anesthetized rats were subjected to a prolonged hemorrhagic shock (mean arterial pressure of 30 to 35 mm Hg for 180 mins) followed by resuscitation . A murine monoclonal antibody to lipopolysaccharide from Escherichia coli and Salmonella, WN1 222-5, was administered at a total dose of 5 mg/kg i.v., starting at the onset of shock (WN1 group) . The control group was treated similarly to the WN1 group but received saline at the same volume as WN1 222-5 . MEASUREMENTS AND MAIN RESULTS: The 48-hr mortality rate was significantly reduced by WN1 222-5 treatment (28.6% in the treatment group vs . 78.6% in the control group; p = .0169) . The characteristic lung injury in this model was significantly reduced in the WN1 group, as assessed by microscopic histopathologic examination increase in lung wet weight (7.60 +/- 0.47 g/kg in the control group vs . 5.14 +/- 0.31 g/kg in the WN1 group; p = .0002), and pulmonary neutrophilic infiltration (myeloperoxidase activity: 1835 +/- 567 mU/g wet weight in the control group vs . 891 +/- 212 mU/g wet weight in the WN1 group) . CONCLUSIONS: These data suggest that a) endotoxin derived from enteric bacteria might play an important role in the pathogenesis of lung injury; and b) antiendotoxin agents, such as WN1 222-5, appear to protect against endogenous bacterial endotoxin-related disorders in severe hemorrhagic shock in rats.

J Bacteriol, 1997 Jun, 179(12), 3866 - 74
Altered localization of HrpZ in Pseudomonas syringae pv . syringae hrp mutants suggests that different components of the type III secretion pathway control protein translocation across the inner and outer membranes of gram-negative bacteria; Charkowski AO et al.; Pseudomonas syringae pv . syringae 61 (Pss61) secretes the HrpZ harpin by a type III protein secretion pathway encoded by a cluster of hrp (hypersensitive response and pathogenicity) and hrc genes . The nine hrc genes represent a subset of hrp genes that are also conserved in the type III virulence protein secretion systems of animal pathogenic Yersinia, Shigella, and Salmonella spp . The hrpJ and hrpU operons contain seven hrc genes (counting hrcQ(A) and hrcQ(B) as one gene), all with additional homologs involved in flagellar biogenesis and secretion, and five of which encode predicted inner membrane proteins . The hrpC and hrpZ operons encode HrcC and HrcJ, respectively, which are associated with the outer membrane . Interposon mutants affected in all of the hrc genes in the hrpJ and hrpU operons and TnphoA-induced hrcC and hrcJ mutants were assayed for altered localization of HrpZ in mid-log-phase cultures by immunoblotting sodium dodecyl sulfate-polyacrylamide gels that were run with various cell fractions . The hrpJ and hrpU operon mutants revealed a novel phenotype of partially reduced accumulation of HrpZ in the total culture (despite wild-type levels of hrpZ operon transcription), all of which was cell bound and equivalent in level to that of cell-bound HrpZ in the wild type . The hrcC and hrcJ mutant cultures accumulated the same total amount of HrpZ as the wild type, but the HrpZ was cell bound . Among all the strains tested, only the hrcC mutant accumulated significant amounts of HrpZ in the periplasm, as indicated by selective release through spheroplasting . Analysis of nonpolar mutations in the hrpU and hrpC operons support the results obtained with polar mutations . These observations indicate that a constant pool of HrpZ is maintained in the cytoplasm of Pss61 despite secretion deficiencies, that the hrpJ and hrpU operons encode an alternative to the Sec (general protein export) pathway for translocation across the inner membrane, that genes in the hrpC operon are necessary for translocation across the outer membrane, and that the Pss61 Hrp system permits study of two genetically distinguishable stages in type III protein secretion.

Poult Sci, 1997 Jun, 76(6), 798 - 801
Assessing the sensitivity of egg yolk antibody testing for detecting Salmonella enteritidis infections in laying hens; Gast RK et al.; The identification of infected commercial poultry flocks has become a pivotal component of efforts to reduce the incidence of egg-associated transmission of Salmonella enteritidis to humans . To assess the sensitivity with which testing for specific antibodies in egg yolks can be applied to detect S . enteritidis infection in laying chickens, groups of hens were orally inoculated with either 10(3), 10(5), or 10(7) cfu of a phage type 13a strain of S . enteritidis . Eggs from these hens were collected for 4 wk after inoculation and yolk samples were tested for antibodies to S . enteritidis flagella by ELISA . All hens that were inoculated with 10(7) cfu of S . enteritidis were detected as infected by the egg yolk ELISA when eggs were tested individually, as were up to 66 and 35% of hens inoculated with 10(5) or 10(3) cfu, respectively . Even when yolks from infected hens were diluted 1:10 in yolk from uninfected hens, specific antibodies could still be found in eggs from 31% of hens given 10(7) cfu of S . enteritidis and 13% of hens given 10(3) cfu . These results demonstrate that egg yolk antibody testing can provide a highly sensitive indication of prior exposure to S . enteritidis, and should accordingly be useful for verifying the effectiveness of programs designed to reduce the incidence of S . enteritidis infection in poultry.

Infect Control Hosp Epidemiol, 1997 Jun, 18(6), 417 - 21
Susceptibility of antibiotic-susceptible and antibiotic-resistant hospital bacteria to disinfectants; Rutala WA et al.; OBJECTIVE: To evaluate whether hospital strains of antibiotic-resistant bacteria exhibited altered susceptibility to disinfectants . DESIGN: Antibiotic-susceptible bacteria were obtained from American Type Culture Collection: Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Salmonella choleraesuis, and Pseudomonas aeruginosa . Hospital strains of antibiotic-resistant bacteria were obtained from clinical isolates, including: S aureus, S epidermidis, E coli, Enterococcus species, K pneumoniae, and P aeruginosa . The Association of Official Analytical Chemist's use-dilution method was used to test these 12 strains of 7 bacterial pathogens for their susceptibility to a phenol and a quaternary ammonium compound . For five pathogens, we tested a susceptible and a more resistant strain in 20 comparative trials (5 pathogens, 2 disinfectants, 2 dilutions per disinfectant) . RESULTS: In our 20 comparative trials, the antibiotic-resistant strains exhibited an increased resistance to the disinfectant in only a single instance . CONCLUSIONS: Our data demonstrate that the development of antibiotic resistance does not appear to be correlated to increased resistance to disinfectants.

J Bacteriol, 1997 Jun, 179(11), 3451 - 7
Isolation and characterization of two genes, waaC (rfaC) and waaF (rfaF), involved in Pseudomonas aeruginosa serotype O5 inner-core biosynthesis; de Kievit TR et al.; Recent studies have provided evidence to implicate involvement of the core oligosaccharide region of Pseudomonas aeruginosa lipopolysaccharide (LPS) in adherence to host tissues . To better understand the role played by LPS in the virulence of this organism, the aim of the present study was to clone and characterize genes involved in core biosynthesis . The inner-core regions of P . aeruginosa and Salmonella enterica serovar Typhimurium are structurally very similar; both contain two main chain residues of heptose linked to lipid A-Kdo2 (Kdo is 3-deoxy-D-manno-octulosonic acid) . By electrotransforming a P . aeruginosa PAO1 library into Salmonella waaC and waaF (formerly known as rfaC and rfaF, respectively) mutants, we were able to isolate the homologous heptosyltransferase I and II genes of P . aeruginosa . Two plasmids, pCOREc1 and pCOREc2, which restored smooth LPS production in the waaC mutant, were isolated . Similarly, plasmid pCOREf1 was able to complement the Salmonella waaF mutant . Sequence analysis of the DNA insert of pCOREc2 revealed one open reading frame (ORF) which could code for a protein of 39.8 kDa . The amino acid sequence of the deduced protein exhibited 53% identity with the sequence of the WaaC protein of S . enterica serovar Typhimurium . pCOREf1 contained one ORF capable of encoding a 38.4-kDa protein . The sequence of the predicted protein was 49% identical to the sequence of the Salmonella WaaF protein . Protein expression by the Maxicell system confirmed that a 40-kDa protein was encoded by pCOREc2 and a 38-kDa protein was encoded by pCOREf1 . Pulsed-field gel electrophoresis was used to determine the map locations of the cloned waaC and waaF genes, which were found to lie between 0.9 and 6.6 min on the PAO1 chromosome . Using a gene-replacement strategy, we attempted to generate P . aeruginosa waaC and waaF null mutants . Despite multiple attempts to isolate true knockout mutants, all transconjugants were identified as merodiploids.

Infect Immun, 1997 Jun, 65(6), 2306 - 12
Role of alphabeta and gammadelta T cells in the host response to Salmonella infection as demonstrated in T-cell-receptor-deficient mice of defined Ity genotypes; Weintraub BC et al.; Salmonella spp . are facultative intracellular bacteria which enter the body through the intestinal tract . We studied the roles of T cells expressing either the alpha and beta chains or the gamma and delta chains of the T-cell receptor (alphabeta T cells or gammadelta T cells, respectively) in the host defense against Salmonella using mice genetically deficient in either alphabeta T cells, gammadelta T cells, or both T-cell subsets . These mutant strains of mice were infected orally or intraperitoneally with Salmonella dublin, and the progression of the disease was monitored by determining bacterial numbers in the feces, gut wall, Peyer's patches, mesenteric lymph nodes, spleen, and liver . Since susceptibility to Salmonella infection in mice is strongly affected by the alleles at the Ity locus, T-cell-mutant mice with either the Ity-sensitive or Ity-resistant phenotype were tested for resistance to S . dublin infection . We found that even though large numbers of intraepithelial and mucosal alphabeta and gammadelta T cells populate the normal intestine, they have no role in controlling the invasion of S . dublin into the intestine or the subsequent bacterial replication in the Peyer's patches or gut wall . Furthermore, systemic infections were equally severe for the first 6 days in normal, alphabeta T-cell-deficient, and gammadelta T-cell-deficient mice, and alphabeta but not gammadelta T cells were required for clearance of S . dublin, regardless of the Ity phenotype . However, mice that lacked both T-cell subsets had higher bacterial counts in their livers 15 to 18 days after infection than did alphabeta T-cell-deficient mice, suggesting that gammadelta T cells can contribute to acquired immunity to S . dublin.

Infect Immun, 1997 Jun, 65(6), 2088 - 93
Synthesis and immunological properties of Vi and di-O-acetyl pectin protein conjugates with adipic acid dihydrazide as the linker; Kossaczka Z et al.; The Vi capsular polysaccharide of Salmonella typhi, a licensed vaccine for typhoid fever in individuals > or = 5 years old, induces low and short-lived antibodies in children, and reinjection does not elicit booster responses at any age . Its immunogenicity was improved by binding Vi to proteins by using N-succinimidyl-3-(2-pyridyldithio)propionate (SPDP) as a linker . Similar findings were observed with the structurally related, di-O-acetyl derivative of pectin {poly-alpha(1-->4)-D-GalpA} designated OAcP . Protein conjugates of Vi and OAcP were synthesized by carbodiimide-mediated synthesis with adipic acid dihydrazide (ADH) as the linker . Hydrazide groups were introduced into proteins (bovine serum albumin or recombinant Pseudomonas aeruginosa exoprotein A) by treatment with ADH and 1-ethyl-3(3-dimethylaminopropyl carbodiimide (EDC) . The resultant adipic acid hydrazide derivatives (AH-proteins), containing 2.3 to 3.4% AH, had antigenic and physicochemical properties similar to those of the native proteins . The AH-proteins were bound to Vi and OAcP by treatment with EDC . The immunogenicity of Vi or OAcP, alone or as protein conjugates, was evaluated in young outbred mice and guinea pigs by subcutaneous injection of 2.5 and 5.0 microg, respectively, of polysaccharide, and antibodies were measured by enzyme-linked immunosorbent assay . All conjugates were significantly more immunogenic than Vi or OAcP alone and induced booster responses with 5- to 25-fold increases of antibodies . Vi conjugates were significantly more immunogenic than their OAcP analogs . A carboxymethyl derivative of yeast beta-glucan enhanced the anti-Vi response elicited by an OAcP conjugate but had no effect on the immunogenicity of Vi or of OAcP alone . Vi and OAcP conjugates synthesized by this scheme will be evaluated clinically.

J Clin Microbiol, 1997 Jun, 35(6), 1316 - 21
Molecular epidemiology of antibiotic resistance of Salmonella enteritidis during a 7-year period in Greece; Tassios PT et al.; A significant increase in the frequency of isolation of Salmonella enteritidis has been observed during recent years in Greece, parallelled by an increasing rate of resistance of this organism to antibiotics . A substantial proportion of ampicillin- and doxycycline-resistant isolates exhibited cross-resistance to drugs of other classes, such as sulfonamides and streptomycin . Isolates of human origin were overall less resistant than those of animal or food-feed origin . Indeed, strains associated with animal infections were characterized by the highest rates of resistance to several antibiotics . These phenotypic data were correlated with genotypic information concerning two distinct populations: isolates from all sources that were resistant only to ampicillin, the drug toward which resistance rates were highest, and a control group of sensitive isolates . Ampicillin resistance was due to a 34-MDa conjugative plasmid . DNA fingerprinting by macrorestriction of genomic DNA revealed two types, A and B, common to both ampicillin-resistant and -sensitive strains, with 80 to 90% of strains being of type A . However, a third type, C, was specific for the sensitive population, representing 17% of those strains . Therefore, although the majority of resistant isolates were genetically related to sensitive ones, there existed a susceptible clone which had not acquired any resistance traits.

Commun Dis Rep CDR Rev, 1997 May 30, 7(6), R87 - 90
Outbreak of Salmonella enteritidis phage type 6 infection associated with food items provided at a buffet meal; Holtby I et al.; Preliminary enquiries following prompt notification of three cases of suspected food poisoning revealed that they had all attended the same three functions during the preceding weekend . Subsequent investigation identified 49 people with gastrointestinal symptoms, 13 of whom were infected with Salmonella enteritidis phage type 6 . Forty-five of those with symptoms, including 11 with confirmed infection, had eaten a buffet meal at a public house . Eating egg sandwiches was strongly associated with infection . Defects in the kitchen structure and the storage and handling of the implicated food items provided the potential for cross contamination . Salmonella was isolated from several environmental sites, including a general purpose cleaning cloth . Two different quiches and pork pies, which were possible vehicles of infection were thought to have been contaminated after being brought into the kitchen . The investigation did not reveal whether or not shell eggs used in the sandwiches were the original source or whether they too had been contaminated during their preparation.

Mutat Res, 1997 May 23, 390(3), 245 - 55
Genotoxicity of six pesticides by Salmonella mutagenicity test and SOS chromotest; Ruiz MJ et al.; Two in vitro tests (Ames test and SOS chromotest), one for bacterial mutagenicity and one for primary DNA damage, were assayed to determine the genotoxic activity of 6 pesticides (atrazine, captafol, Captan, chlorpyrifosmethyl, molinate and tetrachlorvinphos) . Assays were carried out both in the absence and presence of S9 fractions of liver homogenate from rat (Sprague-Dawley) pretreated with Aroclor 1254 . Captan and captafol were genotoxic on both the Ames test and the SOS chromotest . Comparisons with mutagenesis data in Salmonella indicated that the SOS assay detected as genotoxic the pesticides that were mutagenic on the Salmonella test . Non-genotoxic effects were not detected in vitro either in the Salmonella/microsome assay nor in the SOS chromotest when bacterial tester strains were exposed to atrazine, molinate, chlorpyrifosmethyl and tetrachlorvinphos in the absence or presence of S9 mix.

Mutat Res, 1997 May 23, 390(3), 233 - 8
Activity of a nitroalkene derivative, 1-(5-bromofur-2-il)-2-bromo-2-nitroethene, in the Salmonella/microsome assay and the mouse bone marrow micronucleus test; Ramos A et al.; Mutagenicity of a substituted nitroalkene, 1-(5-bromofur-2-il)-2-bromo-2-nitroethene (BNF) was tested in the Salmonella/microsome assay using the strains TA 98, TA 100 and TA 100NR (nitroreductase deficient) . BNF was a direct mutagen in TA 98 and TA 100; the response was lowered when exogenous metabolic activation (S9) was used . A further decrease in mutagenicity was observed in strain TA 100NR, as compared to the parental TA 100, which showed the involvement of nitroreduction in the overall response elicited by BNF . The micronucleus assay was carried out in Swiss male mice which were given a single i.p . dose of 10-20 mg/kg of BNF dissolved in peanut oil, bone marrow being sampled 24 and 48 h later . The micronucleated polychromatic erythrocyte counts (MNPCE) showed a weak response in the dose range of 10-17.5 mg/kg at the second sampling (48 h) and a significant rise for 20 mg/kg at 24 and 48 h.

Int J Food Microbiol, 1997 May 20, 36(2-3), 111 - 25
Development of a quantitative risk assessment model for Salmonella enteritidis in pasteurized liquid eggs; Whiting RC et al.; The performance of hazard analyses and the establishment of critical limits by the food industry are both hampered by the inability to directly relate food processing operations from farm-to-table with their public health impact . Using a 'unit operations' and stochastic simulation approach, data on the frequency of pathogens in raw ingredients, predictive microbiology models for growth and inactivation (thermal and non-thermal), and dose-response models for infectivity were integrated to create a quantitative risk assessment model for a Salmonella enteritidis infection from thermally processed liquid whole eggs made into mayonnaise in the home . The risk assessment indicated pasteurization provides sufficient consumer protection from a high incidence of infected birds and from temperature abuse between the farm and the egg breakers . However scenarios showed how inadequate pasteurization temperatures and/or temperature abuse during storage leads to a hazardous product . This dynamic approach to modeling risk should aid in identification and setting critical control points and assessing the impact of altering food formulations or processes.

Int J Food Microbiol, 1997 May 20, 36(2-3), 97 - 102
Use of predictive microbiology in microbial food safety risk assessment; Walls I et al.; Microbial risk assessment is a newly emerging discipline in the area of food safety . One of the difficulties associated with microbial risk assessment is in determining the number of microorganisms in food at a given time, i.e. . estimating exposure of an individual to the microorganism . Numbers of bacteria in food can change at all stages of food production and processing, depending on the nature of the food and the way it is handled, stored and processed . Predictive microbiology can be used to estimate changes in bacterial numbers, allowing exposure of an individual to a pathogen to be assessed . A survey was sent to scientists in the food industry to determine their perspective on the role of predictive microbiology in conducting microbial risk assessments . In this paper, responses to that survey are presented, as well as examples of the potential risk of foodborne illness from a cooked meat product contaminated with Staphylococcus aureus and hamburger contaminated with Salmonella.

Tidsskr Nor Laegeforen, 1997 May 20, 117(13), 1908 - 10
{Splenic abscess . Diagnosis and treatment}; Rerbakken G et al.; A diagnosis of hospital discharges shows splenic abscess to be a rare condition, with one case per 10,000 discharges . Haematogenous seeding to the spleen from an infection at a distant site, most often endocarditis, has been the most common predisposing condition but an increase has been observed in immuno-suppressed patients too . Fever, leukocytosis and left upper quadrant pain are suggestive, but the signs and symptoms of splenic abscesses are often non-specific . Ultrasound and computed tomography are reliable diagnostic tools . Splenectomy and antibiotics have been the treatments of choice, with increasing use of percutaneous drainage as an alternative, in order to preserve splenic function . We describe a patient with a salmonella splenic abscess that was treated with percutaneous drainage and ciprofloxacin.

Cancer Lett, 1997 May 19, 115(2), 129 - 33
Protective effect of food additives on aflatoxin-induced mutagenicity and hepatocarcinogenicity; Soni KB et al.; Food additives such as turmeric (Curcuma longa), and active ingredient curcumin (diferuloyl methane), asafoetida (flavouring agent), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and ellagic acid were found to inhibit the mutagenesis induced by aflatoxin B1 (AFB1) (0.5 microg/plate) in Salmonella tester strains TA 98 and TA 100 . Turmeric and curcumin, which were the most active, inhibited mutation frequency by more than 80% at concentrations of 2 microg/plate . Other food additives were also significantly effective . Dietary administration of turmeric (0.05%), garlic (0.25%), curcumin and ellagic acid (0.005% each) to rats significantly reduced the number of gammaglutamyl transpeptidase-positive foci induced by AFB1 which is considered as the precursor of hepatocellular neoplasm . These results indicate the usefulness of antioxidant food additives in ameliorating aflatoxin-induced mutagenicity and carcinogenicity.

Mutat Res, 1997 May 12, 376(1-2), 97 - 100
Antigenotoxic activity of natural chlorophylls; Negishi T et al.; Chlorophyllin, a man-made water-soluble form of chlorophyll, is a focus of intensive studies from many laboratories for its antimutagenic and anticarcinogenic properties . Natural chlorophylls, in contrast, have been little studied in this regard . Since yellow-green vegetables are implicated to be protective against human cancers by epidemiological studies, it is important to explore the antigenotoxic properties of natural chlorophylls . Previously, we reported that a chlorophyll sample prepared from Chlorella vulgaris inhibited the mutagenicity of 3-hydroxyamino-1-methyl-5H-pyrido{4,3-b}indole, a direct-acting mutagen, in Salmonella, and that the chlorophyll also showed inhibition of wing spot formation in Drosophila induced by 3-amino-1-methyl-5H-pyrido{4,3-b}indole (Trp-P-2) . We have now prepared several samples of chlorophyll from spinach and chlorella, and studied their effect on the genotoxicity of 4-nitroquinoline 1-oxide (4NQO) in Drosophila . The results showed that the genotoxicity of orally given 4NQO was suppressed by simultaneous administration of the chlorophylls . The mechanisms of this inhibition are discussed.

Mutat Res, 1997 May 12, 376(1-2), 87 - 96
Quantitative structure-activity (QSAR) relationships of mutagenic aromatic and heterocyclic amines; Hatch FT et al.; We extended our previous studies of mutagenic/carcinogenic heterocyclic aromatic amines formed during the cooking of foods to 66 aromatic and 99 heterocyclic amines for which mutagenic potency data are available . The amines require activation by enzymes to form metabolites reactive with DNA and exhibit an enormous range of potency as frameshift mutagens in the Ames/Salmonella assay . To ascertain factors that might influence potency, structural features and quantum mechanical parameters calculated by the Huckel method (and, for a subset of 20 amines, by semi-empirical AM1, and ab initio methods) were analyzed by multiple linear regression . The major findings were: (1) earlier findings on cooked food mutagens and their synthetic congeners can be extended to other amines; (2) mutagenic potency is directly related to the number of fused aromatic rings (size of the aromatic system), the number of ring nitrogen atoms (participation of lone electron pairs in the pi-cloud), and presence of a methyl substituent on a ring nitrogen; (3) potency is inversely related to the energy of the lowest unoccupied molecular orbital (LUMO) of the parent amine . Ford and Griffin (1992) and Sabbioni and Wild (1992) showed that the LUMO energy of the derived nitrenium ion is closely related to its stability (calculated with reference to aniline) . Increased stability has been hypothesized to enhance the probability of adduct formation with DNA by avoiding detoxifying side reactions and increasing the lifetime of the ion . In the large heterogeneous series of amines in our present study the Huckel method energy of the highest occupied molecular orbital (HOMO), rather than the LUMO energy, of the nitrenium ion was marginally related to the potency of the parent amine . However, in the selected subset of 20 amines with ab initio calculation, the LUMO energy of the ion confirmed the previous reports . The contribution of quantum chemical factors to mechanistic insight on the mutagenicity and carcinogenicity of aromatic and heterocyclic amines is still under development.

Vet Rec, 1997 May 3, 140(18), 472 - 7
Meat safety consequences of implementing visual postmortem meat inspection procedures in Danish slaughter pigs; Mousing J et al.; The consequences of a change from a traditional meat inspection procedure, including manual handling, palpation and incision, to an entirely visual postmortem meat inspection procedure in Danish slaughter pigs were assessed by a comparative study of the two methods in 183,383 slaughter pigs . Out of 58 lesion codes (selected with a prevalence > or = 5.5 x 10(-5)), 26 (45 per cent) were assessed either as merely aesthetic or as the healed stage of an earlier lesion and nine (15 per cent) as active, but local processes, occurring only in non-edible tissue . Five lesion codes (9 per cent) were assessed as active, non-abscessal processes occurring in edible tissue, caused by swine-specific pathogens and 10 (17 per cent) were abscessal or pyaemic lesions occurring in edible tissue . Seven lesion codes (12 per cent) may be associated with consumer health hazards (two frequently and five rarely), and one with occupational health hazards . It was estimated that per 1000 carcases, an additional 2.5 with abscessal or pyaemic lesions (in edible tissue) containing Staphylococcus aureus, 4 x 10(-4) containing ochratoxin, 0.2 with arthritis due to Erysipelothrix rhusiopathiae, 0.1 with caseous lymphadenitis, 0.7 faecally contaminated with Salmonella species, and 3.4 faecally contaminated with Yersinia enterocolitica would remain undetected as a result of changing from the traditional to the visual inspection procedure . Two valuable reasons for implementing a visual control system are the potential for decreased cross-contamination (no handling, cutting and incision) and reduced inspection costs . The resources released as a result may be reallocated to hygiene and surveillance programmes.

Equine Vet J, 1997 May, 29(3), 230 - 3
An outbreak of abortion in mares associated with Salmonella abortusequi infection; Madic J et al.; An abortion outbreak occurred in a herd of 38 horses, 26 of which were pregnant mares . Twenty-one mares aborted between 5-10 months of gestation . In no case were there indications of impending abortion . Pathoanatomical, histopathological, virological and bacteriological examinations were carried out on 4 aborted fetuses . Histopathology identified Gram-negative bacteria compatible with salmonella in all 4 placentae . By subsequent bacteriological examination Salmonella abortusequi was isolated as the single causative agent in each case . Nonmotile Salmonella abortusequi with antigenic formula 4,12:-:- was isolated from one of the 4 fetuses . The described episode of equine abortion clearly indicates that Salmonella abortusequi has not been eradicated from Europe as previously thought.

Trans R Soc Trop Med Hyg, 1997 May-Jun, 91(3), 347 - 9
Short courses of ofloxacin for the treatment of enteric fever; Nguyen TC et al.; Typhoid fever continues to be a major public health problem in tropical countries, exacerbated in recent years by the spread of multi-drug resistant strains of Salmonella typhi . Short treatment courses of fluoroquinolones are effective, and have the advantage of reduced cost and increased compliance, but the optimal length of treatment is unknown . In an open, randomized comparison, 107 adults with uncomplicated enteric fever (95 of whom had positive blood cultures for S . typhi and 5 for S . paratyphi) were treated with oral ofloxacin, 15 mg/kg/d for 2 d or 10 mg/kg/d for 3 d . Mean fever clearance times were the same in the 2 treatment groups (97 h) . There were 7 treatment failures, one in the 2 d group and 6 in the 3 d group (P = 0.07) . Three of the 5 patients infected with nalidixic acid resistant strains of S . typhi had treatment failures, compared with 4 of 90 with nalidixic acid sensitive isolates (P < 0.0001; relative risk 13.5, 95% confidence interval 4.1-43%) . Treatment with ofloxacin for 2 or 3 d is equally effective in adults with uncomplicated enteric fever caused by nalidixic acid sensitive strains of S . typhi . The epidemiology and management of nalidixic acid resistent typhoid needs further investigation.

Vet Microbiol, 1997 May, 56(1-2), 111 - 24
Epidemiology and virulence assessment of Salmonella dublin; Rice DH et al.; Six strains of Salmonella dublin with distinct antimicrobial susceptibility patterns and/or plasmid profiles were repeatedly isolated from calves in a calf rearing facility . Three of the six strains were isolated from numerous calves during outbreaks of clinical salmonellosis while the other three were not . These strains were compared for their ability to adhere to and internalize in human intestinal epithelial cells (Caco-2) and in bovine alveolar macrophages (BAM), to survive in BAM, and to cause lethal infection in female BALB/c mice . All six strains of S . dublin demonstrated an ability to adhere to and internalize in both Caco-2 cells and in BAM . However, strain differences in the level of adhesion and/or internalization in Caco-2 cells and BAM were demonstrated . Most strains were able to persist but not proliferate in BAM . One outbreak-associated strain which readily attached and internalized in eukaryotic cells in vitro was avirulent to mice at the dose tested . The remaining five strains were virulent to mice . In vitro measures of virulence attributes were not clearly correlated with virulence among S . dublin strains measured either as prevalence in calves during outbreaks of disease or as mouse lethality . Also, there was no association between prevalence of strains in calves during outbreaks of clinical salmonellosis and lethality in mice.

J Surg Res, 1997 May, 69(2), 249 - 54
Immunization with antibodies that mimic LPS protects against gram negative bacterial sepsis; Klaerner HG et al.; We developed 9H1.B11, an anti-idiotypic anti-deep core/lipid A (DCLA), murine monoclonal antibody (mAb) that mimics the conserved DCLA region of lipopolysaccharide (LPS) . It recognizes an epitope in the variable region of an DCLA mAb, binds to the murine macrophage cell surface, and inhibits LPS-induced macrophage cytokine secretion . We hypothesized that (1) active immunization with mAb 9H1.B11 would be associated with the development of anti-DCLA antibodies and (2) immunization would protect against subsequent gram negative bacterial challenge . Mice were immunized for 8 weeks before intraperitoneal (ip) challenge with Escherichia coli O111:B4 bacteria . Control animals were immunized with an irrelevant IgM antibody 8133 (negative control) or with LPS derived from Salmonella minnesota Re bacteria (positive control) . Sera from immunized mice were collected, and titers against the core region of LPS (Re) and against LPS derived from the infecting E . coli strain were determined . Mice immunized with mAb 9H1.B11 developed measurable titers against S . minnesota Re LPS but not against the challenge strain of E . coli . However, immunization with 9H1.B11 on S . minnesota Re LPS protected against subsequent infection due to E . coli O111:B4 (100% survival) . The group of mice immunized with IgM 8133 exhibited only 25% survival . The development of an anti-S . minnesota Re LPS titer after immunization with 9H1.B11 provides further evidence that a portion of 9H1.B11 mimics the conserved DCLA region of LPS . We believe that this approach holds considerable promise and plan further studies to define the mechanism by which protective capacity occurs.

Food Chem Toxicol, 1997 May, 35(5), 433 - 41
Effects of marinating on heterocyclic amine carcinogen formation in grilled chicken; Salmon CP et al.; This study compared heterocyclic aromatic amines in marinated and unmarinated chicken breast meat flame-broiled on a propane grill . Chicken was marinated prior to grilling and the levels of several heterocyclic amines formed during cooking were determined by solid-phase extraction and HPLC . Compared with unmarinated controls, a 92-99% decrease in 2-amino-1-methyl-6-phenylimidazo{4,5-b}pyridine (PhIP) was observed in whole chicken breast marinated with a mixture of brown sugar, olive oil, cider vinegar, garlic, mustard, lemon juice and salt, then grilled for 10, 20, 30 or 40 min . Conversely, 2-amino-3, 8-dimethylimidazo{4,5-f}quinoxaline (MeIQx) increased over 10-fold with marinating, but only at the 30 and 40 min cooking times . Marinating reduced the total detectable heterocyclic amines from 56 to 1.7 ng/g, from 158 to 10 ng/g and from 330 to 44 ng/g for grilling times of 20, 30 and 40 min, respectively . The mutagenic activity of the sample extracts was also measured, using the Ames/Salmonella assay . Mutagenic activity was lower in marinated samples cooked for 10, 20 and 30 min, but higher in the marinated samples cooked for 40 min, compared with unmarinated controls . Although a change in free amino acids, which are heterocyclic amine precursors, might explain the decrease in PhIP and increase in MeIQx, no such change was detected . Marinating chicken in one ingredient at a time showed that sugar was involved in the increased MeIQx, but the reason for the decrease in PhIP was unclear . PhIP decreased in grilled chicken after marinating with several individual ingredients . This work shows that marinating is one method that can significantly reduce PhIP concentration in grilled chicken.

J Clin Pathol, 1997 May, 50(5), 437 - 9
Standardisation of polymerase chain reaction for the detection of Salmonella typhi in typhoid fever; Chaudhry R et al.; To improve the diagnosis of Salmonella typhi infection, a polymerase chain reaction (PCR) assay was developed for the amplification of the dH flagellin gene of S typhi . Primers were designed from dH flagellin gene sequence which will give an amplification product of 486 base pairs . In tests to study the specificity of the assay, no amplification was seen in non-salmonella strains or salmonella strains with flagellar gene other than "d" . Sensitivity tests determined that 28 pg of S typhi target DNA or 3 x 10(2) target bacteria could be detected by the PCR assay . Subsequently, the PCR technique was used for detection of S typhi in blood or clot cultures from 84 patients clinically suspected of having typhoid fever, and from 20 healthy control subjects . Twenty five of 84 samples from clinically suspected cases were positive by PCR; four of which were culture negative . No amplification was seen in samples from patients who were culture positive for organisms other than S typhi or from controls . The time taken for each sample for PCR analysis was less than 48 hours compared with three to five days for blood or clot culture . PCR appeared to be a promising diagnostic test for typhoid fever.

Neuroimaging Clin N Am, 1997 May, 7(2), 223 - 9
Intracranial bacterial infections in patients with AIDS; Cohen WA; Nontuberculous, nonsyphilitic intracranial bacterial infections in HIV-positive individuals may be nonspecific presentations of unusual organisms, such as R . equi, B . henselae, Nocardia sp . or L . monocytogenes . In addition, more common organisms, such as Staphylococcus, Streptococcus, or Salmonella sp . may cause an unusually severe infection . In general, the imaging appearance of these bacterial infections is similar to that in immunocompetent individuals.

J Laryngol Otol, 1997 May, 111(5), 489 - 90
A rare case of Salmonella neck abscess; Ray J et al.; A case of a deep neck abscess caused by Salmonella enteritidis in a 29-year-old previously undiagnosed diabetic patient is reported . Review of relevant literature has shown 11 cases of Salmonella neck abscess . Predisposing conditions include immunosuppression due to any cause . Salmonella sp . should be included in the differential diagnosis of head and neck abscesses in predisposed individuals and treated accordingly.

J Infect, 1997 May, 34(3), 237 - 42
Typhoid fever in hospitalized children in Singapore; Oh HM et al.; A study was conducted to determine the clinical features and severity of typhoid fever in children admitted to the Communicable Disease Centre, Singapore . Over a 5 year period (1990-94), 40 children had documented culture-proven typhoid fever . Nine of the 40 children (22.5%) were below the age of 5 years . The predominant presenting symptoms were fever and diarrhoea . Pneumonia and ileus were the only complications observed . No patient in the series died . Ten Salmonella typhi isolates were multi-drug resistant . The majority of the children were treated with chloramphenicol and ceftriaxone . Typhoid fever appears to be a mild disease in Singapore children.

Acta Paediatr, 1997 May, 86(5), 547 - 8
A relapse of paratyphoid fever after treatment with ciprofloxacin in a child with congenital biliary atresia; Eltringham IJ et al.; This report describes a relapse of Salmonella paratyphi B infection in a child with biliary atresia, following 2 weeks of treatment with ciprofloxacin . The recrudescence was complicated by the development of osteomyelitis and was treated with chloramphenicol, trimethoprim, ceftriaxone and ampicillin in succession.

Am J Physiol, 1997 May, 272(5 Pt 2), H2353 - 60
Endothelin-1 in rat endotoxemia: mRNA expression and vasoreactivity in pulmonary and systemic circulations; Curzen NP et al.; Endothelin-1 (ET-1) is a vasoconstrictor and proinflammatory peptide, but its role in the vascular response to sepsis is unknown . After intraperitoneal injection of male Wistar rats (300 g) with 20 mg/kg of Salmonella enteritidis lipopolysaccharide (LPS), the expression of ET-1 mRNA was significantly increased in pulmonary artery and aorta within 1 h and arterial ET-1 concentration was elevated . Despite this increase in ET-1 production, there was no difference in baseline systemic or pulmonary arterial pressures between control and endotoxin-treated rats, and, furthermore, combined ETA/ETB receptor antagonism using bosentan produced reductions in systemic and pulmonary arterial pressures that were not greater than the modest fall seen in controls . However, bosentan completely antagonized the hemodynamic effects of exogenous ET-1 in controls but only weakly antagonized its effects in LPS animals . After LPS the initial (ETB-mediated) systemic hypotensive responses to ET-1 were attenuated, but the subsequent systemic pressor responses were not . By contrast, the increases in pulmonary arterial pressure in response to ET-1 and the ETB receptor agonist sarafotoxin S6c were significantly reduced in LPS animals . Vascular ET-1 mRNA expression and arterial ET-1 concentration are elevated after LPS treatment in rats, but the functional activity of ET-1 cannot be exposed by combined ETA/ETB receptor antagonism, possibly because of an alteration in the functional status of ET receptors.

Am J Physiol, 1997 May, 272(5 Pt 1), G1195 - 200
Neutrophil margination and extravasation in sinusoids and venules of liver during endotoxin-induced injury; Chosay JG et al.; Neutrophils contribute to liver damage during endotoxin shock . The objective of this investigation was to document where neutrophils localize in the hepatic vasculature and whether they migrate out of sinusoids or postsinusoidal venules . A well-characterized model of galactosamine and endotoxin shock and immunostaining for neutrophil-associated migration inhibition factor-related protein complex 8/14 S100 calcium-binding proteins were used . Treatment of C3Heb/FeJ mice with 100 micrograms/kg Salmonella abortus equi endotoxin alone or in combination with 700 mg/kg galactosamine induced a time-dependent increase of neutrophil margination in sinusoids and postsinusoidal venules at 4 h . The number of venular neutrophils decreased in both groups at later time points without evidence for transmigration . Extravasation of neutrophils was only observed from sinusoids in galactosamine plus endotoxin-treated animals between 4 and 7 h, which correlated with parenchymal cell injury . After endotoxin alone, large numbers of neutrophils remained sequestered in sinusoids without injury . These data suggest that neutrophils cause hepatocellular injury during endotoxemia after extravasation and are less likely to cause damage when sequestered in the vasculature . In the liver, neutrophils migrate out of sinusoids and not out of postsinusoidal venules.

J Formos Med Assoc, 1997 May, 96(5), 346 - 52
Surgical experience with Salmonella-infected aneurysms of the abdominal aorta; Luo CY et al.; Five patients, aged between 64 and 75 years with Salmonella-infected abdominal aortic aneurysms were surgically treated between 1993 and 1995 at the National Cheng Kung University Hospital . Cultures of aneurysmal wall tissue and blood yielded Salmonella enteritidis Group B in three patients and Salmonella choleraesuis in the remaining two . All patients presented with fever and abdominal or back pain . Pulsatile masses were noted in only two patients . Infrarenal abdominal infected aneurysms were demonstrated by computed tomography and aortography in each patient . The five patients underwent aneurysmal resection with in situ graft reconstruction from 1 to 20 days after the diagnosis was made . The graft was wrapped with an omental pedicle . Duodenal repair was performed in one patient due to an aortoduodenal fistula found during surgery . He died 19 days after surgery because of duodenal leakage and uncontrolled sepsis . Four patients survived and remained well 11 to 34 months (mean, 25 mo) after surgery . Postoperatively, only one patient developed adhesion ileus and required enterolysis . Parenteral antimicrobial therapy was continued in all patients after surgery for 2 to 4 weeks; only one patient had an additional 4 months of oral antibiotics . Although the number of patients was small, the survival rate was high, at 80% . Our experience suggests that Salmonella-infected aneurysms of the abdominal aorta can be successfully treated by resection of the aneurysm with extensive debridement followed by in situ graft interposition with omentum wrapping . Once diagnosed, the patients should be scheduled for surgery as soon as possible . Antibiotics should be continued parenterally for at least 2 to 4 weeks postoperatively . While long-term suppressive antibiotic therapy is usually recommended, it might not be essential with our surgical approach.

J AOAC Int, 1997 May-Jun, 80(3), 491 - 504
VIDAS enzyme-linked fluorescent immunoassay for detection of Salmonella in foods: collaborative study; Curiale MS et al.; The VIDAS SLM method for detection of Salmonella was compared with the Bacteriological Analytical Manual (BAM)/AOAC culture method in a collaborative study . Twenty laboratories participated in the evaluation . Each laboratory tested one or more of 6 test products: milk chocolate, nonfat dry milk, dried whole egg, soy flour, ground black pepper, and ground raw turkey . No significant differences (P < 0.05) were observed between the 2 methods . The 2 methods were in agreement for 99% of 1544 samples analyzed . Of the 20 samples out of agreement, 8 were VIDAS SLM positive and BAM/AOAC negative, and 12 were VIDAS SLM negative and BAM/AOAC positive . The VIDAS SLM method for detection of Salmonella in foods has been adopted first action by AOAC INTERNATIONAL.

Phytochemistry, 1997 May, 45(2), 321 - 4
A bioactive triterpene from Lantana camara; Barre JT et al.; Lantana camara afforded a novel triterpene 22 beta-acetoxylantic acid and the known triterpenes, lantic acid, 22 beta-dimethylacryloyloxylantonolic acid, a mixture of 22 beta-dimethylacryloyloxy lantanolic acid and 22 beta-angeloyloxylantanolic acid and lantanolic acid . 22 beta-Acetoxylantic acid showed antimicrobial activity against Staphylococcus aureus and Salmonella typhi . This compound and 22 beta-dimethylacryloyloxy lantanolic acid also showed antimutagenic activity.

Biochem Mol Biol Int, 1997 May, 41(6), 1125 - 36
Mutagenic and genotoxic activities of four pesticides: captan, foltaf, phosphamidon and furadan; Saxena S et al.; The mutagenic and genotoxic potential of four pesticides viz . captan, foltaf, phosphamidon and furadan was evaluated by the Ames mutagenicity assay and their DNA damaging ability on radiation repair defective E . coli K-12 strains respectively . The mutagenic spectrum revealed captan to be most mutagenic in the absence of metabolic activation, while the presence of S9 mix led to an attenuated mutagenic response . Foltaf, phosphamidon and furadan were detected as relatively weaker mutagens . A significant decrease in the survival of SOS defective mutants, recA, lexA and pol- of E . coli was observed as compared to their wild-type counterparts in the presence of the pesticides . The role of SOS repair genes gains further support from the Salmonella strains triggering the error-prone SOS response.

J Med Microbiol, 1997 May, 46(5), 377 - 82
Epidemiological analysis of strains of Salmonella enterica serotype Enteritidis from foodborne outbreaks occurring in Italy, 1980-1994; Nastasi A et al.; Polymerase chain reaction (PCR-) ribotyping was performed on 243 strains of Salmonella enterica serotype Enteritidis isolated during the years 1980-1994 from 58 foodborne outbreaks occurring in different regions of Italy . The majority (37) of the outbreaks were attributed to phage type (PT) 4, followed by PT1 (seven outbreaks); the latter was identified in 1993 in Italy in epidemic strains of Enteritidis . In eight cases more than one phage type was recognised from a single event . Nine PCR-ribotypes (PCR-RTs) were detected, with a strong prevalence of PCR-RTs f7 and e5 (23 and 21 outbreaks, respectively) . In two instances two distinct PCR-RTs were identified within strains from a single outbreak . All but one of the PT1 outbreaks were caused by PCR-RT f7, whereas PT4 outbreaks could be subdivided into six subsets . Clustering of isolates was consistent with data obtained from epidemiological investigations . PCR-ribotyping proved to be an effective and reliable tool for subtyping isolates of Enteritidis belonging to the most frequent phage types . Nevertheless, in terms of laboratory expertise and lack of inter-laboratory standardisation, this typing technique is best suited for reference laboratories.

Commun Dis Intell, 1997 May 1, 21(9), 120 - 2
Salmonella in Victoria, 1997: the story so far; Lester R et al.; The Infectious Diseases Unit of the Department of Human Services, Victoria, reported an increased incidence of Salmonella infections in early 1997 . To 21 April 1997, 944 notifications had been received, passing the previous year's total of 915 . Five outbreaks of five separate serovars have been investigated and traced to their sources . The outbreaks, their sources and the control measures undertaken are described . Further clusters of other Salmonella serovars are being investigated.

Appl Environ Microbiol, 1997 May, 63(5), 2082 - 5
Identification of Salmonella abortusovis by PCR amplification of a serovar-specific IS200 element; Beuzon CR et al.; Field and collection isolates of Salmonella abortusovis carry one IS200 element in a distinct chromosome location . IS200 is not found in the corresponding region of the chromosome of other Salmonella serovars . Sequencing of the boundaries of the S . abortusovis-specific IS200 insertion permitted the design of primers for the amplification of this IS200 element by PCR . Isolates of S . abortusovis are identified by the amplification of a DNA fragment of about 900 bp or larger . PCR amplification of DNA from salmonellae other than S . abortusovis yields either a fragment of about 200 bp or no product . The high specificity of the assay is confirmed by the absence of cross-reactivity with the following templates: (i) sheep DNA, (ii) DNAs from abortion-causing agents other than S . abortusovis, and (iii) DNAs from microorganisms that do not cause abortion but are common in flocks.

Clin Infect Dis, 1997 May, 24(5), 998 - 1000
Characteristics of typhoid fever in children and adolescents in a major metropolitan area in the United States; Misra S et al.; To examine the epidemiology of typhoid fever in children in an area that was not endemic, we analyzed 55 cases of typhoid fever in children and adolescents who were < or = 18 years and whose cases were reported to the Chicago and suburban Cook County Health Departments over 7 years . Cases had positive blood and/or stool cultures for Salmonella typhi . The ethnic distribution of the patients was as follows: 25% Asian, 22% Hispanic, 15% African American, 9% Caucasian, 18% other, and 11% unknown . Of the 55 cases, 35% were aged 0-5 years, 25% were aged 6-10 years, 31% were aged 11-15 years, and 9% were aged 16-18 years . Twelve patients did not have a history of travel . All patients recovered; none became carriers . Symptoms in 41 patients whose charts were available for review included fever (100%), diarrhea (77%), vomiting (50%), and dehydration (30%) . Bacteremia was documented in 27 (66%) of 41 cases . In 17 of 41 cases, the household contacts were food handlers or health care workers . Eight (31%) of 26 isolates were resistant to both ampicillin and trimethoprim-sulfamethoxazole . The findings in our study were as follows: typhoid fever occurred frequently in children aged 0-5 years (in contrast with reports from areas of endemicity), approximately 20% of patients did not have a history of travel, and multidrug-resistant strains were prevalent.

J Immunol, 1997 May 1, 158(9), 4381 - 8
In vivo production and function of IL-12 p40 homodimers; Heinzel FP et al.; The bioactivity of IL-12 is mediated by heterodimers of disulfide-linked p35 and p40 protein subunits . Homodimeric p40 competes with heterodimer for binding to the high affinity IL-12R and inhibits IL-12 bioactivity in vitro . However, the production and significance of p40 homodimer as a cytokine antagonist in vivo have not been determined . In these studies, we observed increased amounts of both IL-12 p40 monomer and homodimer in the serum of C57BL/6 mice following injection of 300 microg of Salmonella enteritidis LPS . Homodimer constituted between 20 and 40% of the total circulating p40 in endotoxemic sera, as confirmed by both Sephacryl S-100 gel filtration and p40-specific immunoprecipitation analyses . Similar relative amounts of homodimer and monomer were observed in endotoxemic BALB/c, C57BL/6, IFN-gamma-deficient C57BL/6 mice and C57BL/6 mice previously infected with bacille Calmette-Guerin . To determine whether IL-12 p40 homodimer was capable of antagonizing IL-12-dependent IFN-gamma responses in vivo, we pretreated C57BL/6 mice with purified rIL-12 p40 homodimer before i.p . challenge with endotoxin . Mice treated with 40 to 80 microg of p40 homodimer generated 80 to 82% less circulating IFN-gamma during acute endotoxemia than saline controls (p < 0.01) . We conclude that p40 homodimer is produced in vivo, functions as a cytokine antagonist in the context of the mouse model of acute endotoxemia, and may represent a novel form of self-regulating cytokine response.

Infect Immun, 1997 May, 65(5), 1786 - 92
The spv genes on the Salmonella dublin virulence plasmid are required for severe enteritis and systemic infection in the natural host; Libby SJ et al.; The pathogenic role of the spv (Salmonella plasmid virulence) genes of Salmonella dublin was determined in the natural, bovine host . Since the lack of overt signs of enteritis or enterocolitis due to Salmonella infections in mice has limited the development of a convenient experimental system to study enteric disease, we used calves to study the contribution of the spv genes to S . dublin-induced salmonellosis . Since the SpvR transcriptional regulator is required for expression of the spvABCD operon, we constructed an spvR knockout mutation in a calf-virulent strain of S . dublin . Calves were infected with the wild-type strain, an spvR mutant, and an spvR mutant containing a complementing plasmid . Calves that were infected with the wild type or the complemented spvR mutant rapidly developed severe diarrhea and became moribund . Calves that were infected with the spvR mutant showed little or no clinical signs of systemic salmonellosis and developed only mild diarrhea . The survival and growth of the wild-type strain and the spvR mutant were determined by using blood-derived bovine monocytes . Wild-type S . dublin survived and grew inside cells, while the spvR mutant did not proliferate . These results suggest that the spv genes of S . dublin promote enhanced intracellular proliferation in intestinal tissues and at extraintestinal sites in the natural host.

J Clin Microbiol, 1997 May, 35(5), 1224 - 30
Rapid detection of Salmonella enterica with primers specific for iroB; Baumler AJ et al.; The iroB gene of Salmonella enterica is absent from the chromosome of the related organism Escherichia coli . We determined the distribution of this gene among 150 bacterial isolates, representing 51 serotypes of different Salmonella species and subspecies and 8 other bacterial species which are frequent contaminants during routine enrichment procedures by Southern hybridization . An iroB-specific DNA probe detected homologous sequences in all strains of S . enterica, including serotypes of S . enterica subsp . enterica (I), salamae (II), diarizonae (IIIb), and houtenae (IV) . No hybridization signal was obtained with strains of Salmonella bongori or other bacterial species . In contrast, hybridization with a DNA probe specific for purD, a purine biosynthesis gene, detected homologs in all bacterial species tested . Primers specific for iroB were used to amplify this gene from 197 bacterial isolates by PCR . The iroB gene could be PCR amplified from S . enterica subsp . enterica (I), salamae (II), diarizonae (IIIb), houtenae (IV), arizonae (IIIa), and indica (VI), but not from S . bongori or other bacterial species . Thus, PCR amplification of iroB can be used to distinguish between S . enterica and other bacterial species, including S . bongori . A combination of preenrichment in buffered peptone water supplemented with ferrioxamine E and amplification of iroB by magnetic immuno-PCR allowed detection of S . enterica in albumen within 24 h . In conclusion, PCR amplification of iroB is a new sensitive and selective method which has the potential to rapidly detect S . enterica serotypes.

Nucleic Acids Res, 1997 May 1, 25(9), 1694 - 700
The specificity of sty SKI, a type I restriction enzyme, implies a structure with rotational symmetry; Thorpe PH et al.; The type I restriction and modification (R-M) enzyme from Salmonella enterica serovar kaduna ( Sty SKI) recognises the DNA sequence 5'-CGAT(N)7GTTA, an unusual target for a type I R-M system in that it comprises two tetranucleotide components . The amino target recognition domain (TRD) of Sty SKI recognises 5'-CGAT and shows 36% amino acid identity with the carboxy TRD of Eco R124I which recognises the complementary, but degenerate, sequence 5'-RTCG . Current models predict that the amino and carboxy TRDs of the specificity subunit are in inverted orientations within a structure with 2-fold rotational symmetry . The complementary target sequences recognised by the amino TRD of Sty SKI and the carboxy TRD of Eco R124I are consistent with the predicted inverted positions of the TRDs . Amino TRDs of similar amino acid sequence have been shown to recognise the same nucleotide sequence . The similarity reported here, the first example of one between amino and carboxy TRDs, while consistent with a conserved mechanism of target recognition, offers additional flexibility in the evolution of sequence specificity by increasing the potential diversity of DNA targets for a given number of TRDs . Sty SKI identifies the first member of the IB family in Salmonella species.

Mutat Res, 1997 Apr 24, 390(1-2), 105 - 12
Cytogenetic effects of softwood kraft pulp bleaching effluents and methanesulfonyl chloride in Chinese hamster ovary cells; Sipi P et al.; The genotoxicity of effluents collected from a conventional 5-stage softwood kraft pulp bleaching process was studied in Chinese hamster ovary (CHO) cells in vitro . Spent liquor from the first chlorination stage (C/D), where elemental chlorine and chlorine dioxide had been used in equal proportions, was shown to induce a dose-dependent increase in sister chromatid exchanges (SCEs) without metabolic activation (4-h treatment), with a maximum increase of 1.6 times over the control level at 204 microliters/ml; this dose also induced 15.5- and 20.5-fold increases in cells with chromatid-type chromosomal aberrations after 4-h and a 20-h treatment, respectively . Another C/D stage spent liquor from a process where the ratio of elemental chlorine and chlorine dioxide had been 9:1 produced a 40.5-fold elevation of cells with chromatid-type aberrations at 204 microliters/ml (20-h treatment) . This sample clearly increased chromosomal aberrations also when tested as a concentrate (4-h treatment), which showed that the observed clastogenicity was not unspecifically due to the relatively large volumes used in the treatments with the unconcentrated liquors . In general, the use of rat liver S9 mix reduced the genotoxicity of the spent liquors . The results agree with earlier findings on the Salmonella mutagenicity of the same C/D samples: both the prokaryotic and eukaryotic assays showed a reduction in genotoxicity when the amount of elemental chlorine in the bleaching process was reduced . An effluent sample collected from the alkaline stage of the process was not clastogenic with or without metabolic activation . Methanesulfonyl chloride, a new compound identified in bleaching plant air, was found to be induce chromosomal aberrations in the presence of S9 mix.

Carbohydr Res, 1997 Apr 21, 299(3), 159 - 64
Synthesis of colitose-containing oligosaccharide structures found in polysaccharides from Vibrio cholerae O139 synonym Bengal using thioglycoside donors; Oscarson S et al.; The syntheses of the two colitose-containing trisaccharides 8-methoxycarbonyloctyl (3,6-dideoxy-alpha-L-xylo-hexopyranosyl)-(1-->2)-beta-D-galactopyranosyl -(1-->3)-2-acetamido-2-deoxy-beta-D-glucopyranoside and 8-methoxycarbonyloctyl beta-D-galactopyranosyl-(1-->3)-{(3,6- dideoxy-alpha-L-xylo-hexopyranosyl)-(1-->4)}-2-acetamido-2-deoxy-beta-D- glucopyranoside, and tetrasaccharide 8-methoxycarbonyloctyl (3,6-dideoxy-alpha-L-xylo-hexopyranosyl)-(1-->2)-beta-D-galactopyranosyl - (1-->3)-{(3,6-dideoxy-alpha-L-xylo-hexopyranosyl)-(1-->4)}-2-acetamido-2 -deoxy- beta-D-glucopyranoside are described . The oligosaccharides correspond to structures found in the capsular polysaccharide and the lipopolysaccharide of Vibrio cholerae O139 and also to lipopolysaccharide structures of E . coli O55 and Salmonella greenside . The colitose residues were introduced via dimethyl(methylthio)sulfonium trifluoromethanesulfonate promoted glycosylations using colitose thioglycosides as glycosyl donors.

FEMS Microbiol Lett, 1997 Apr 15, 149(2), 239 - 44
Structural characterization of lipid A obtained from Pantoea agglomerans lipopolysaccharide; Tsukioka D et al.; Lipopolysaccharide isolated from Pantoea agglomerans showed higher priming and triggering activities for macrophages in terms of tumor necrosis factor production than other lipopolysaccharides . To identify the difference in biological activities of lipopolysaccharide of Pantoea agglomerans from other lipopolysaccharides on the basis of structure, we determined the structure of the lipid A part, which is the biological center of lipopolysaccharides, by quantitative analysis, nuclear magnetic resonance spectroscopy and mass spectrometry . Lipopolysaccharide of Pantoea agglomerans is constructed with at least two kinds of lipid A of different levels of acylation . One is of the same type as that of Escherichia coli with hexa-acyl lipid A and the other is the Salmonella minnesota type with hepta-acyl lipid A.

FEMS Microbiol Lett, 1997 Apr 15, 149(2), 173 - 80
Induction of flagellation and a novel agar-penetrating flagellar structure in Salmonella enterica grown on solid media: possible consequences for serological identification; Guard-Petter J; Salmonella enterica grown on solid medium containing iron, thiosulfate and 100 mM hexoses and amino acids underwent cell surface differentiation involving increased flagellation (electrophoretic isotypes 60, 54 and 50 kDa), conversion from rough to smooth lipopolysaccharide, and assembly of a matrix that penetrated 1.4% agar . Flagellation was also induced in the avian pathogen S . enterica var Pullorum, which is diagnostically defined as aflagellate . Induction correlated closely with a simple colonial color change when Hektoen Enteric agar was used as the basal growth medium . Group D1 egg-contaminating Salmonella grown under inducing conditions deviated from their expected H-antigen immunoreactivity, suggesting possible consequences for the interpretation of the Kauffman-White identification scheme.

Int J Food Microbiol, 1997 Apr 15, 35(3), 239 - 50
The evaluation of a fluorogenic polymerase chain reaction assay for the detection of Salmonella species in food commodities; Chen S et al.; The TaqMan LS-50B PCR Detection System facilitates the automated and direct detection of polymerase chain reaction (PCR) products . The system employs the 5' nuclease activity of Taq DNA polymerase to hydrolyse a Salmonella specific internal fluorogenic probe for monitoring the amplification of a 287-bp region of the Salmonella invA gene . Using the fluorogenic 5' nuclease assay, 164 Salmonella strains representing all the subspecies of Salmonella enterica were detected while over 50 non-Salmonella strains were not detected . The detection limit of the assay was two colony forming units (cfu) per PCR reaction when a pure culture of S . typhimurium was used . Six protocols for the isolation of PCR-amplifiable DNA were evaluated using chicken carcass rinses, ground beef, ground pork and raw milk contaminated with Salmonella . Of the six DNA isolation protocols, a modified sample preparation protocol using the EnviroAmp kit was chosen for subsequent studies because it was reliable, easy to use and efficient for the isolation of PCR-amplifiable DNA from foods . A detection limit of 3-7 cfu per PCR reaction was obtained using food samples that were pre-enriched overnight and then inoculated with Salmonella . The detection limit was below 3 cfu/25 g or 25 ml when foods inoculated with Salmonella were pre-enriched overnight . Naturally contaminated foods (50 chicken carcass rinses and 60 raw milk samples) were examined using both the fluorogenic 5' nuclease assay and a modified semi-solid rappaport vassiliadis (MSRV) culture method . Thirty four of the 110 samples tested were Salmonella-positive and 74 were Salmonella-negative by both the 5' nuclease assay and the MSRV method . Two samples were Salmonella-positive by the 5' nuclease assay, but negative by the MSRV method . The correlation between the 5' nuclease assay and the MSRV method was over 98%.

Int J Food Microbiol, 1997 Apr 15, 35(3), 223 - 30
Comparative study of the protective effect against Salmonella colonisation in newly hatched SPF chickens using live, attenuated Salmonella vaccine strains, wild-type Salmonella strains or a competitive exclusion product; Methner U et al.; There is a need to prevent intestinal colonisation by Salmonella enteritidis and S . typhimurium in newly hatched chicks . Treatment with an undefined bacterial flora is not acceptable to regulatory agencies in some countries because of the potential risk of transmitting pathogens . A defined culture with a potency and stability equivalent to those of an undefined culture has not yet been developed . Since attenuated Salmonella vaccine strains could possess the colonisation characteristics but not the virulence of Salmonella wild-type strains, they could inhibit colonisation of the challenge organism . S . typhimurium live vaccines registered in Germany (Zoosaloral H, Salmonella vac T), S . enteritidis aroA and S . typhimurium aroA strains, S . enteritidis, S . typhimurium and S . infantis wild-type strains or a competitive exclusion product (Broilact) were used as pretreatment cultures and evaluated for their inhibitory effects against S . enteritidis and S . typhimurium colonisation in newly hatched SPF chickens . Day-old chicks were administered a pretreatment culture and infected orally with variants of S . enteritidis or S . typhimurium wild type-strains resistant to nalidixic acid or rifampicin 1 day after pretreatment . On days 2 and 6 after infection, viable numbers of the challenge strain in liver and caeca were determined . The results for birds pretreated with Broilact showed a distinct protective effect against both S . enteritidis and S . typhimurium at a challenge dose of 10(4) cfu/bird . After pretreatment of chicks with S . enteritidis and S . typhimurium wild-type strains, the greatest degree of inhibition of caecal colonisation was produced using isogenic strains . Colonisation after infection with non-isogenic strains could not be prevented but only reduced for a brief period . These effects were also observed after administration of aroA strains of S . enteritidis and S . typhimurium but the protective effect was considerably lower than after pretreatment with wild-type Salmonella strains . Inoculation with attenuated S . typhimurium vaccines resulted in a weak but significantly reduced colonisation by S . typhimurium . Colonisation by S . enteritidis could not be diminished by either of the S . typhimurium vaccine strains . The results indicate in principle the potency of Salmonella vaccine strains to inhibit Salmonella wild-type colonisation in newly hatched chicks . Potential vaccine candidates should be tested for their capacity to prevent intestinal colonisation in newly hatched chicks.

Int J Food Microbiol, 1997 Apr 15, 35(3), 195 - 204
Estimating the incidence of food-borne Salmonella and the effectiveness of alternative control measures using the Delphi method; Henson S; The paper describes the use of the Delphi method to estimate the incidence of food-borne Salmonella in the UK and the effectiveness of alternative control measures . A panel of experts of food-borne Salmonella participated in the Delphi survey, which involved five rounds of questioning taking place in the period July 1993 to January 1994 . Participants were asked to give initial estimates for a number of parameters and invited to revise these estimates through progressive rounds of the survey at which the group responses were reported back . This process resulted in a reduction in the variation between the estimates given by individual experts . The final estimated annual incidence of food-borne Salmonella in the UK was 537,000, although significant variation remained between, individual estimates . The foods judged to be the most important modes of transmission were poultry and poultry products (50% of cases) and eggs and egg products (26% of cases) . The panel was also requested to estimate the effectiveness of strategies available to reduce the incidence of food-borne Salmonella from all sources . The most effective methods were judged to be food irradiation and mandatory application of HACCP, although there were significant differences in the judged effectiveness of these technologies for individual respondents . The paper demonstrates the efficacy of the Delphi method as a mechanism for reconciling differences between expert judgements of the incidence of food-borne disease and the effectiveness of alternative control strategies.

J Chromatogr A, 1997 Apr 11, 767(1-2), 53 - 61
Analysis of a monophosphoryl lipid A immunostimulant preparation from Salmonella minnesota R595 by high-performance liquid chromatography; Hagen SR et al.; MPL immunostimulant, a 4'-monophosphoryl lipid A (MLA) preparation obtained from the lipopolysaccharide of Salmonella minnesota R595, is being developed for several clinical indications . MPL comprises a mixture of MLA congeners that contain 4, 5, and 6 fatty acids . In this paper, we report a new high-performance liquid chromatography (HPLC) method for analyzing the congener composition and purity of MPL . MPL is first derivatized with dinitrobenzyloxyamine (DNBA), resulting in incorporation of the dinitrobenzyl chromophore at the reducing end of all MLA congeners . DNBA-MPL is then analyzed by reversed-phase HPLC on a Waters NovaPak C18, 4 microns particle size, 300 mm x 3.9 mm column . Optimal separation of DNBA-MLA species is obtained using a linear gradient of 10% to 80% isopropanol-water (95:5, v/v), 5 mM tetrabutylammonium dihydrogenphosphate (TBAP), in acetonitrile-water (95:5, v/v), 5 mM.TBAP, over 45 min . A synthetic compound, corresponding to a hexaacyl MLA congener, is used for determination of the detector response factor, allowing the MLA content of MPL (i.e., purity) to be determined . Overall, this method provides better separation, higher sensitivity, and is faster and saler than previous methods used for the analysis of MPL.

J Toxicol Environ Health, 1997 Apr 11, 50(5), 451 - 62
3-Chloro-p-toluidine hydrochloride: in vitro mutagenicity studies for human health hazards determinations; Stankowski LF Jr et al.; 3-Chloro-p-toluidine hydrochloride (CPT-HCl) is an aniline derivative used in the manufacture of the dye palatine fast yellow; it is also registered as a selective, low-volume-use (< 45 kg/yr) avicide . Three in vitro mutagenicity tests of CPT-HCl were performed according to methods recommended by the U.S . Environmental Protection Agency (EPA): the Ames/Salmonella assay, the Chinese hamster ovary/hypoxanthine-guanine phosphoribosyl-transferase (CHO/HPRT) mammalian cell forward gene mutation assay, and the CHO chromosome aberration assay . CPT-HCl did not display mutagenic activity using the Ames/Salmonella or CHO/HPRT assays . However, CPT-HCl induced statistically significant, concentration-dependent, metabolically activated increases in the proportion of aberrant cells and aberrations/cell in cultured CHO cells . Results are suggestive of minimal mutagenicity effects associated with exposure to anilines and their derivatives.

J Mol Biol, 1997 Apr 11, 267(4), 865 - 80
Phage P22 tailspike protein: crystal structure of the head-binding domain at 2.3 A, fully refined structure of the endorhamnosidase at 1.56 A resolution, and the molecular basis of O-antigen recognition and cleavage; Steinbacher S et al.; The tailspike protein of Salmonella phage P22 is a viral adhesion protein with both receptor binding and destroying activities . It recognises the O-antigenic repeating units of cell surface lipopolysaccharide of serogroup A, B and D1 as receptor, but also inactivates its receptor by endoglycosidase (endorhamnosidase) activity . In the final step of bacteriophage P22 assembly six homotrimeric tailspike molecules are non-covalently attached to the DNA injection apparatus, mediated by their N-terminal, head-binding domains . We report the crystal structure of the head-binding domain of P22 tailspike protein at 2.3 A resolution, solved with a recombinant telluromethionine derivative and non-crystallographic symmetry averaging . The trimeric dome-like structure is formed by two perpendicular beta-sheets of five and three strands, respectively in each subunit and caps a three-helix bundle observed in the structure of the C-terminal receptor binding and cleaving fragment, reported here after full refinement at 1.56 A resolution . In the central part of the receptor binding fragment, three parallel beta-helices of 13 complete turns are associated side-by-side, while the three polypeptide strands merge into a single domain towards their C termini, with close interdigitation at the junction to the beta-helix part . Complex structures with receptor fragments from S . typhimurium, S . enteritidis and S . typhi253Ty determined at 1.8 A resolution are described in detail . Insertions into the beta-helix form the O-antigen binding groove, which also harbours the active site residues Asp392, Asp395 and Glu359 . In the intact structure of the tailspike protein, head-binding and receptor-binding parts are probably linked by a flexible hinge whose function may be either to deal with shearing forces on the exposed, 150 A long tailspikes or to allow them to bend during the infection process.

MMWR Morb Mortal Wkly Rep, 1997 Apr 11, 46(14), 308 - 10
Multidrug-resistant Salmonella serotype Typhimurium--United States, 1996; A modelling approach to the quantification of the benefits of a national surveillance programme; Batchelar Agriculture Centre, Palmerston North, New Zealand . sansonr@pnorth.mqm.govt.nz

A simulation modelling approach was developed to investigate the effects of a reduction in funding for animal health surveillance on the probability of diagnosis of a currently-exotic species of Salmonella if it were introduced into New Zealand . Both severe and mild clinical-disease outbreaks were hypothesized . The probabilities of diagnosis for a single outbreak on a cattle farm under the current surveillance programme were 0.742 and 0.328 for severe and mild clinical-disease episodes respectively, reducing to 0.018 and 0.005 respectively under the reduced surveillance programme . The impacts of these probabilities on the likely time delays from introduction into New Zealand before a definitive diagnosis was reached and the resultant numbers of infected properties were estimated for three different epidemic scenarios . For the best-case epidemic, the median time to diagnosis under the current surveillance programme was 4 weeks (by which time there was still only the index property infected), but under the reduced surveillance programme, the median time to diagnosis was over 1.5 years . Under the most-likely epidemic scenario, the mean time to diagnosis under the current programme was 4 weeks (by which stage there were two infected properties), whereas the median time to diagnosis under the reduced programme was 40 weeks (by which time there were 88 infected herds) . With the worst-case epidemic, the median time to diagnosis under the current surveillance programme was still 4 weeks with only two infected properties; however the median time to diagnosis under the reduced programme was 33 weeks by which stage there were 90 infected farms.

Biometals, 1997 Apr, 10(2), 95 - 103
Siderophore activity of chemically synthesized dihydroxybenzoyl derivatives of spermidines and cystamide; Reissbrodt R et al.; Chemically synthesized dihydroxybenzoyl derivatives of spermidine and cystamide containing two-, three- and four-bidentates with the hydroxyl groups in 2,3 or 3,4 position were examined in cross-feeding tests using Gram-negative siderophore indicator strains carrying different iron-related markers, and two Mycobacterium spp . The catecholates were unable to feed tonB mutants of E . coli and S . typhimurium as well as the fepA, fiu, cir mutant of E . coli, pointing to a tonB- and fepA, cir, fiu-dependent transport . Bis(2,3-dihydroxybenzoyl)derivatives promoted Salmonella spp, E . coli, K . pneumoniae and P . aeruginosa strains significantly better than did 3,4-dihydroxybenzoyl derivatives . N4-substituted spermidines acted more effectively than non-substituted derivatives . Bis(2,3-dihydroxybenzoyl) cystamide was superior to the other catecholates tested in growth promotion of Gram-negative bacteria . The two four-bidentates and the tri-bidentate reacted to K . pneumoniae in an inhibitory mode . The position of the hydroxyl groups did not significantly influence the growth promotion of M . smegmatis and M . fortiutum in the cases of substituted spermidines and of cystamides.

Avian Dis, 1997 Apr-Jun, 41(2), 490 - 5
Status of Salmonella gallinarum-pullorum infections in poultry in Zambia; Sato Y et al.; Ten outbreaks of Salmonella gallinarum-pullorum infections on poultry farms in Zambia were investigated . Three cases were seen in day-old broiler chickens and were diagnosed by culture as S . gallinarum-pullorum and characterized as pullorum disease because the mortality was only in the first few weeks . Another case was diagnosed by culture from broiler parent stock . Day-old chicks from two of the three cases were supplied by a hatchery . Five cases in 5-to-18-month-old layer chickens were diagnosed by culture as S . gallinarum-pullorum and characterized as fowl typhoid because of the clinical disease appearing after 5 months of age and the typical lesions of fowl typhoid . The last case was in 5-month-old village-bred fowls and was diagnosed by culture and clinical manifestation as fowl typhoid . Outbreaks of S . gallinarum-pullorum are still manifest in Zambia . Clinically, both pullorum disease and fowl typhoid were observed, and it was indicated that hatchery infection plays an important role in the transmission of S . gallinarum-pullorum.

Avian Dis, 1997 Apr-Jun, 41(2), 455 - 60
Application of normal avian gut flora by prolonged aerosolization onto turkey hatching eggs naturally exposed to Salmonella; Primm ND et al.; A commercial preparation of normal avian gut flora (NAGF) was aerosolized for an extended period over turkey hatching eggs during pipping and hatching to examine any protective effects against natural exposure to salmonellae . Turkey hatching eggs, produced by salmonellae-infected breeder flocks and hatched in a commercial hatchery with a history of salmonellae contamination, were used in two trials . In Trial 1, four doses of NAGF inoculum per hatching egg were aerosolized through an automated hatcher fogging system during the final 48 hr of the pipping and hatching process . In Trial 2, two doses of NAGF inoculum were aerosolized in a like manner . In both trials, poults were exposed to Salmonella montevideo during hatching, as indicated by samples collected at the time of pull . At day 7, treated poults in both trials were culture negative for salmonellae and control poults were culture positive for salmonellae . In Trial 1, control poults were infected with Salmonella brandenburg, and in Trial 2, control poults were infected with S . montevideo . These studies justify further critical evaluation of the protective effects of prolonged aerosolization of normal avian gut flora during pipping and hatching against salmonellae colonization in turkey poults.

Avian Dis, 1997 Apr-Jun, 41(2), 438 - 41
Heterophil response to intraperitoneal challenge with invasion-deficient salmonella enteritidis and Salmonella-immune lymphokines; Ziprin RL; The present work compared the accumulation of intraperitoneal heterophils in day-of-hatch chicks following treatment with Salmonella enteritidis-immune lymphokine (ILK) and challenge with various strains of Salmonella enteritidis (SE) . Day-of-hatch chicks received ILK by intraperitoneal injection and were challenged 1 hr later by intraperitoneal inoculation with one of the following SE strains: a wild-type, SE 890034-3; a delta cya-12 delta cyp-11 avirulent vaccine strain, chi 4357; and an invasion-deficient strain, InvA::kan, chi 4420 . Four hours after challenge heterophils were recovered from the peritoneal cavity by lavage . The concentration of heterophils in the recovered lavage fluid was determined . Heterophil concentrations increased in response to challenge with each SE strain but there was a lower response to the invasion-deficient strain . The difference was statistically significant . This diminished heterophil response to challenge with invasion-deficient salmonellae supports existing evidence that the initial defensive reaction occurs at the earliest stages of the Salmonella-host interaction.

Avian Dis, 1997 Apr-Jun, 41(2), 354 - 60
The effect of the flow of air on horizontal transmission of Salmonella enteritidis in chickens; Nakamura M et al.; Horizontal transmission of Salmonella enteritidis and the effect of airflow on spreading were examined in 80 5-wk-old chickens divided into five groups . Sixteen chickens in each group were placed in four cages in a row separated by wire . One among four chickens placed in a cage at the downwind end of the row was inoculated orally with 10(9) colony-forming units of S . enteritidis . Cecal droppings, drinking water, and feed were cultured every day . Horizontal transmission was rapid in the row with low air velocity but slow in the row with high air velocity . However, in another experiment, where the inoculated chicken was situated in a cage upstream in the airflow, horizontal transmission was equally rapid whether the airflow was rapid or slow . Contamination of feed and water never preceded the appearance of positive cecal droppings . These findings suggest that the rapidity of horizontal transmission of S . enteritidis may be affected by airflow patterns.

Avian Dis, 1997 Apr-Jun, 41(2), 296 - 303
Salmonella enteritidis contamination of eggs from hens inoculated by vaginal, cloacal, and intravenous routes; Miyamoto T et al.; Laying hens were inoculated intravaginally (IVg) once (IVg-single) or three times (IVg-triple), intracloacally (IC), or intravenously (IV) with Salmonella enteritidis (SE) phage type 4 . Eggs tested were significantly (P < 0.05) fewer positive in group IC than in other groups . SE was recovered from egg contents in the groups IVg-single (9.6%), IVg-triple (4.2%), and IV (11.5%) . IVg and IC inoculation resulted in colonization of the cloaca and lower portions of the oviduct but not the portion above the isthmus, whereas IV inoculation resulted in colonization of the entire oviduct . Only IV inoculation resulted in colonization of the ovary . In group IV, SE was recovered from three of six eggs found in the oviduct at necropsy, but in other groups, SE was not recovered from 53 eggs in the oviduct . The results suggested that the SE infection of vagina resulted in a frequent incidence of contaminated eggs and that SE adhered to the eggs from the contaminated vagina might pass through shells and shell membranes.

Zentralbl Veterinarmed B, 1997 Apr, 44(2), 87 - 98
{Detection methods for Salmonella abortus ovis and examinations in sheep flocks in northern Baden-Württemberg}; Sting R et al.; Investigations into the incidence of Salmonella abortus ovis (S . abortus ovis) infections should not be neglected in diagnosis of ovine abortion cases . For detection of this pathogen agent, direct cultivation, as well as pre-enrichment combined with enrichment procedures in tetrathionate or Rappaport-Vassiliadis medium, should be performed with respect to the features of S . abortus ovis . The detection limit of S . abortus ovis using pre-enrichment and enrichment media could be determined using 6.5 x 10(3)-6.5 x 10(4) bacteria . For subsequent cultivation of S . abortus ovis Gassner, XLD or Rambach agar are suitable . In infected sheep showing no excretion of S . abortus ovis, the pathogen can be detected by serological studies using microagglutination or the ELISA test . The ELISA test proved to be more sensitive than the microagglutination test, detecting antibodies against S . abortus ovis in 17% of the 814 sheep tested . The microagglutination test revealed positive results in only 2% of the sheep tested.

Vaccine, 1997 Apr-May, 15(6-7), 700 - 8
A murine model of intranasal immunization to assess the immunogenicity of attenuated Salmonella typhi live vector vaccines in stimulating serum antibody responses to expressed foreign antigens; Galen JE et al.; The lack of a practical small animal model to study the immunogenicity of Salmonella typhi-based live vector vaccines expressing foreign antigens has seriously impeded the vaccine development process . For some foreign antigens, stimulation of serum IgG antibody is the desired, protective immune response . We administered to mice, by orogastric or intranasal (i.n.) routes, attenuated delta aroC delta aroD S . typhi CVD 908 carrying a plasmid encoding fragment C (fragC) of tetanus toxin fused to the eukaryotic cell receptor binding domain of diphtheria toxin (fragC-bDt), and monitored serum antibody . While orogastric inoculation of three doses was not immunogenic, i.n . immunization elicited high titers of serum IgG tetanus antitoxin, generating peak ELISA geometric mean titers (GMT) of 27024 and 35658 with 10(8) and 10(9) c.f.u . dosages, respectively; 10(9) c.f.u . i.n . of an delta aroA S . typhimurium live vector stimulated a peak antitoxin GMT of 376 405 . Mice immunized with the S . typhi live vector were 100% protected against challenge with 100 50% lethal doses of tetanus toxin that rapidly killed all control mice . Intranasal immunization with two doses of S . typhi expressing unfused fragment C under control of an anaerobically-activated promoter derived from nirB stimulated significantly higher titers of serum neutralizing antitoxin than fused fragC-bDt controlled by the same promoter (GMT 0.10 AU ml-1 vs 0.01 AU ml-1, P = 0.0095) . Two i.n . doses of S typhi encoding fragC under control of powerful constitutive promoter 1pp led to significantly higher peak serum neutralizing antitoxin titers than the otherwise identical construct utilizing the nirB promoter (peak GMT 0.72 AU ml-1 vs 0.10 AU ml-1, P = 0.022) . The i.n . route of inoculation of mice may constitute a practical breakthrough that could expedite the development of some S . typhi-based live vector vaccines by allowing, for the first time, quantitative measurement of serum antibody responses to candidate constructs following i.n . mucosal immunization.

Vaccine, 1997 Apr-May, 15(6-7), 659 - 63
Protection in a gerbil model of amebiasis by oral immunization with Salmonella expressing the galactose/N-acetyl D-galactosamine inhibitable lectin of Entamoeba histolytica; Mann BJ et al.; Infection with the enteric parasite Entamoeba histolytica can result in colitis and dysentery as well as abscesses at extra-intestinal sites . An effective vaccine must be able to protect against both mucosal and systemic disease . In this study an attenuated Salmonella strain that expressed a portion of the GalNAc lectin of E, histolytica was used to orally immunize gerbils . Animals were challenged by intrahepatic injection of amebic trophozoites . A significant decrease in size of amebic liver abscesses was observed in orally immunized animals . Oral immunization with a Salmonella-based vaccine was as effective as systemic immunization for protection against systemic challenge.

J Korean Med Sci, 1997 Apr, 12(2), 105 - 10
The etiology and clinical characteristics of mesenteric adenitis in Korean adults; Lee JH et al.; This study is aimed at investigating the etiology and clinical characteristics of mesenteric adenitis in Korean adults, prospectively . Clinical manifestations of fifteen patients who presented with the acute onset of right lower quadrant pain and sonographically enlarged mesenteric lymph nodes and normal appendix were evaluated . For etiologic diagnosis, stool culture, serologic test for Epstein-Barr virus, and Widal test were performed . Colonoscopy with mucosal biopsies and microbial tissue cultures were performed in 12 of 15 patients . Of fifteen patients 6 were male and the average age was 29.9 (17 approximately 41) years . Associated symptoms were diarrhea (80%), fever (73%), nausea and vomiting (27%) . Right lower quadrant tenderness was observed in all cases but rebound tenderness was observed only in 26.7% of the cases . Etiology was identified in 7 cases (47%): 2 Yersinia enterocolitica infection, 2 non-typhoidal Salmonella infection, 2 tuberculosis, and 1 typhoid fever . In colonoscopic examination, signs of active inflammation were observed in 9 cases (75%) and inactive or normal findings in 3 cases (25%) . All of our patients, except for the patients with tuberculosis and typhoid fever who needed specific antibiotic therapy, improved spontaneously without using antibiotics . In conclusion, the etiology of mesenteric adenitis in Korean adults seems to be different from that of western countries . Furthermore, mesenteric adenitis in Korean adults is a clinical syndrome, frequently found in a relatively young age group, which improves spontaneously unless specific anti-microbial agents are indicated by microbiological tests, such as tuberculosis or typhoid fever.

J Clin Microbiol, 1997 Apr, 35(4), 1016 - 20
Detection of motility and putative synthesis of flagellar proteins in Salmonella pullorum cultures; Holt PS et al.; Salmonella pullorum is a host-adapted pathogen of poultry previously thought to be nonmotile and nonflagellated . We discovered that motility can be induced in this organism under special medium conditions, and this motility was observed in 39 of 44 S . pullorum isolates tested . The migration appeared to occur only on the medium surface and not within the medium itself, indicating that swimming may not be responsible for this event . Agar concentration, carbohydrate concentration and type, and temperature of incubation all affected the motility . Flagellar stains and transmission electron micrographs of the motile S . pullorum culture showed long fibrous appendages resembling flagella extending from the cells, but these appendages were thinner and less numerous than the flagella observed on Salmonella enteritidis . Antisera to G flagellar antigens reacted strongly with the induced-motility S . pullorum culture, indicating that G epitopes were expressed on these cells . These results indicate that, contrary to the paradigm which held that S . pullorum is nonmotile and nonflagellated, motility can be induced in S . pullorum and that the organism appears to have the capacity to produce flagella.

Microbiology, 1997 Apr, 143 ( Pt 4), 1471 - 9
Genomic relationships between selected phage types of Salmonella enterica subsp . enterica serotype typhimurium defined by ribotyping, IS200 typing and PFGE; Olsen JE et al.; The genomic relationship between isolates representing 17 definitive phage types (DTs) of Salmonella enterica subsp . enterica serotype typhimurium (S . typhimurium) were analysed using three different typing methods: IS200 typing using the restriction enzymes EcoRI and PvuII, ribotyping using SmaI and EcoRI, and PFGE using XbaI . These methods were used to study four DTs in greater detail; in all 18 (DT 49), 10 (DT 110), five (DT 120) and seven (DT 135) isolates were studied . The combined data generated two large clusters, which could be divided into five groups . Within the first cluster, a close similarity was indicated between isolates of the following phage types: group A-DTs 44, 49, 135 and 204c, with DT 9 distantly related; group B-DTs 95 and 99; and group C-DTs 104a, 110 and 120 . The other large cluster contained group D-DTs 10, 20 and 146, with DT 12 distantly related, and group E-DTs 69, 103 and 153 . The same grouping was observed by principal component analysis, but a minimum spanning tree linked DT 12 to group E and not group D in this analysis . Among the typing methods used, IS200 gave the best representation of the overall similarity between the S . typhimurium isolates . Five different IS200 profiles were obtained among isolates belonging to DT 49 . Only one profile was observed within each of the phage types DT 110, 120 and 135 . All isolates within each of these four phage types were of one ribotype . Isolates of DT 49 showed four PFGE patterns, while one pattern was present within isolates of the three other phage types . Members of these four phage types were found to be clonally related as they formed tight subclusters separated from isolates of other phage types.

Acta Paediatr Jpn, 1997 Apr, 39(2), 218 - 21
Ofloxacin versus co-trimoxazole in the treatment of typhoid fever in children; Secmeer G et al.; Ofloxacin has been successfully used in the treatment of typhoid fever and Salmonella infectious of adults for many years . However, it has rarely been tried for the typhoid fever of children . In the present study, the therapeutic efficacy of ofloxacin in the treatment of typhoid fever in children was compared to that of co-trimoxazole . Out of 41 patients with bacteriologically documented typhoid fever, those with co-trimoxazole-resistant strains received 20 mg/kg ofloxacin twice daily for 10 days, and those with co-trimoxazole-susceptible bacteria were given 60 mg/kg co-trimoxazole twice daily for 10 days . Both groups were compared according to the clinical variables (apyrexia, resolution of gastrointestinal, central nervous system reactions and articular symptoms) and the time when cultures became negative . All patients in both groups were cured without relapse . Apyrexia, resolution of gastrointestinal, central nervous system reactions and articular symptoms were obtained in a significantly shorter time with ofloxacin than with co-trimoxazole (P < 0.05) . The interval between onset of therapy and the time when cultures became negative was significantly shorter in the ofloxacin group than in the co-trimoxazole group (P = 0.005) . Ofloxacin seems to be a good alternative in the treatment of typhoid fever caused by co-trimoxazole resistant salmonellae in children aged less than 16 years . It is well tolerated by the patients and it causes no side effects with short-term usage.

Lett Appl Microbiol, 1997 Apr, 24(4), 261 - 4
The cross-contamination and survival of Salmonella enteritidis PT4 on sterile and non-sterile foodstuffs; Bradford MA et al.; The ability of two strains of Salmonella enteritidis PT4 to cross-contaminate from inoculated egg droplets on surfaces onto melon or beef (sterile or non-sterile) was investigated . When the foods were placed on these surfaces where egg droplets were still wet, cross-contamination occurred within 1 s onto every piece of food . It took at least 1 min for all the food pieces to be contaminated when egg droplets had been allowed to dry . Both strains were capable of rapid growth on melon and beef (sterile or non-sterile) at 20 degrees C, but growth rates on beef appeared to be slowed by pre-exposure to either 4 or -18 degrees C.

Lett Appl Microbiol, 1997 Apr, 24(4), 243 - 8
Optimization of RAPD for fingerprinting Salmonella; Hilton AC et al.; Random amplification of polymorphic DNA (RAPD) is proving to be a useful technique in studying the epidemiology of micro-organisms . The technique can be troublesome and time consuming to establish due to the essentially empirical approach to optimization . By standardization of certain parameters and use of a commercially available PCR buffer optimization kit, a particularly promising primer was identified and RAPD conditions for a highly discriminatory and reproducible characterization of Salmonella isolates was achieved . In addition, a technique to obtain reproducible RAPD fingerprints of Salmonella isolates without the need to purify genomic DNA is described.

J Appl Microbiol, 1997 Apr, 82(4), 507 - 10
Salmonella DNA persistence in natural seawaters using PCR analysis; Dupray E et al.; The risks of false-positive responses were examined when using the polymerase chain reaction (PCR) method for the detection of Salmonella in the marine environment (water and shellfish) . The degradation rates of DNA, both free and from dead Salmonella, were evaluated in natural seawaters maintained at 10 degrees and 20 degrees C, using PCR with Vir and invA primers . The DNA of dead Salmonella was detected up to 55 d in seawater collected in winter and stored at 10 degrees C . But in summer, the persistence was shorter: 10 d or even 2 d for a smaller inoculum (3 x 10(3) Salmonella ml-1) . The role of the planktonic organisms present in spring and summer was pinpointed . For free DNA, the persistence times were shorter: from 2 to 4 d at 20 degrees C, and from 3 to 8 d at 10 degrees C showing that the nuclease activity of marine organisms is higher at warm temperatures . These data led us to recommend careful interpretations of direct PCR results, especially during cold periods and for samples collected close to terrestrial discharges of high concentrations of live, dead or lysed Salmonella . PCR is a rapid, specific and sensitive method, but should be applied with care to marine samples, in order to avoid false-positive responses.

J Appl Microbiol, 1997 Apr, 82(4), 494 - 8
Conventional and molecular approaches to isolates of Salmonella hadar from sporadic and epidemic cases; Fantasia M et al.; In September 1994 an outbreak of gastroenteritis occurred in 437 people who had consumed lunch in the canteen of a factory in Central Italy . Salmonella sp . was isolated from stools of 99 patients and in 73 of them Salmonella hadar was identified . This is the first outbreak caused by this serotype described in Italy . In order to examine the genotypic basis of the epidemic strains, molecular typing was applied to sporadic strains isolated before and after the outbreak episode . For this purpose phage type, resistance to antibiotics, DNA plasmid profile and sites of insertion of the mobile element of IS200 were determined . The epidemic strains were genetically distinct from the non-epidemic isolates; they were shown to be phage type 26, harbouring four small plasmids, were resistant to nalidixic acid and showed a unique characteristic IS200 fingerprint . The typing methods used in this study allowed the identification and discrimination of the outbreak strains from related isolates . They can thus be considered as a tool for epidemiological purposes . In addition we should point out the emerging resistance to nalidixic acid, largely used in veterinary medicine, in Salm . hadar.

Eur J Obstet Gynecol Reprod Biol, 1997 Apr, 72(2), 207 - 11
Salmonella enteritidis in an endometriotic ovarian cyst; Burgmans JP et al.; Isolated Salmonella infections are rare . In view of the rarity, we present a case of a 16-year-old patient with an endometriotic ovarian cyst where Salmonella enteritidis was isolated from aspirated material from the cyst . We include a review of the world literature on ovarian Salmonella infection from 1966 to June 1996.

Immunopharmacology, 1997 Apr, 36(1), 9 - 15
Hydrolysis of thalidomide abrogates its ability to enhance mononuclear cell synthesis of IL-2 as well as its ability to suppress the synthesis of TNF-alpha; Shannon EJ et al.; Thalidomide is effective in the treatment of inflammatory conditions like erythema nodosum leprosum in leprosy patients, and aphthous ulcers in AIDS patients . Its mechanism of action is uncertain and reports of its effect on the synthesis of inflammatory cytokines such as IL-2 and TNF-alpha are contradictory . As thalidomide is labile to spontaneous hydrolysis at pH 7.4, studies were carried out to explore the effects of deliberate hydrolysis or the ability of thalidomide to modulated cytokine production by human mononuclear cells stimulated in vitro with Staphylococcal enterotoxin A (SEA)(IL-2) or lipopolysaccharide from Salmonella minnesota (LPS)(TNF-alpha) . Unhydrolyzed thalidomide at 4.0 micrograms/ml consistently enhanced the synthesis of IL-2 in SEA-stimulated cells, and suppressed the synthesis of TNF-alpha in LPS-stimulated cells; whereas, hydrolyzed thalidomide had no enhancing effect on SEA stimulated-cell synthesis of IL-2 or suppressive effect on LPS stimulated-cell synthesis of TNF-alpha . These findings demonstrate that thalidomide's ability in vitro to enhance IL-2 and to suppress TNF-alpha in stimulated cells is dependent on the intact molecule and underscore the necessity to employ thalidomide under appropriate physicochemical conditions.

Epidemiol Infect, 1997 Apr, 118(2), 97 - 103
Antimicrobial resistance of Salmonella enterica typhimurium DT104 isolates and investigation of strains with transferable apramycin resistance; Low JC et al.; An examination of salmonella isolates collected by the Scottish Agricultural College Veterinary Services Division from April 1994 to May 1995 was conducted to determine the extent to which Salmonella enterica serotype Typhimurium phage type 104 (DT104) occurred and to investigate the antimicrobial resistance patterns of isolates . Typhimurium DT104 was the predominant salmonella and was isolated from nine species of animal . All isolates of this phage type possessed resistance to at least one antimicrobial and 98% of the isolates were resistant to multiple antimicrobials with R-type ACTSp the predominant resistance pattern . Various other resistance patterns were identified and transferable resistance to the veterinary aminoglycoside antimicrobial apramycin was demonstrated in three strains . A retrospective study for gentamicin resistance in isolates from the Scottish Salmonella Reference Laboratory collection revealed a human isolate of Typhimurium DT104 resistant to gentamicin but sensitive to apramycin and a bovine isolate with apramycin and gentamicin resistance.

J Med Microbiol, 1997 Apr, 46(4), 307 - 13
A three-way ribotyping scheme for Salmonella serotype Typhimurium and its usefulness for phylogenetic and epidemiological purposes; Guerra B et al.; Ribotyping of Salmonella serotype Typhimurium strains was optimised as a tool for epidemiological and phylogenetic purposes . Of five restriction endonucleases evaluated on a series of 84 isolates, HincII, SalI and PvuII were the most useful, generating 13, 9 and 9 ribotypes with 17, 11 and 18 polymorphic restriction sites, and attaining a discrimination index (DI) of 0.81, 0.53 and 0.59, respectively . The combination of results from tests with the three enzymes provided further discrimination (19 ribotypes, DI=0.84) . It proved useful for clonal analysis, defining 19 clonal lines with a remarkable degree of genetic heterogeneity, that were grouped into two major clusters (including 12 and 7 lines, respectively) at a significance level of 0.65 . When the attributes of this system were compared with those of phage typing, it was found that ribotyping showed higher typability and sensitivity, supporting its use as an appropriate molecular method . In tracing the molecular epidemiology of Typhimurium strains in Asturias, six lines were found that could be considered endemic and were represented by organisms implicated in salmonellosis throughout the period of study; another four lines included organisms isolated from meat, water or both.

Arthritis Rheum, 1997 Apr, 40(4), 694 - 703
Induction of alternative splicing of HLA-B27 by bacterial invasion; Huang F et al.; OBJECTIVE: Alternative splicing of certain class I major histocompatibility complex pre-messenger RNA (pre-mRNA) is known to lead to generation of a cell-free soluble protein analog . This study was undertaken to examine whether this process occurs with HLA-B27, whether the process is modified by arthritis-causing bacteria, and whether the assembly of the soluble molecules follows the same pathway as the integral parent molecules . METHODS: Alternative splicing of pre-mRNA was analyzed by reverse transcriptase-polymerase chain reaction, and assembly of soluble HLA-B27 by immunoprecipitation followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography . RESULTS: There was alternative splicing of the pre-mRNA of HLA-B27 . The process could be amplified by invasion with Salmonella or Yersinia bacteria . The soluble HLA-B27 was assembled in a pathway similar to that of the parent molecule . CONCLUSION: The association between arthritis-causing bacteria and HLA-B27 positive cells is a complex event . Soluble HLA-B27 is a potential key player.

Infect Immun, 1997 Apr, 65(4), 1267 - 72
Naturally occurring deletions in the centisome 63 pathogenicity island of environmental isolates of Salmonella spp; Ginocchio CC et al.; We have identified several environmental isolates of Salmonella senftenberg and S . litchfield which carry a deletion encompassing a vast segment of the centisome 63 region of the Salmonella chromosome . The deletion includes the entire inv, spa, and hil loci, which are required for entry of Salmonella spp . into mammalian cells . Consequently, these isolates were found to be markedly deficient in the ability to enter cultured epithelial cells . In contrast, no deletions were found in the corresponding regions of the chromosomes of clinical isolates of these serovars; consequently, these isolates were found to be highly invasive for cultured epithelial cells . These data confirm the importance of the centisome 63 region of the Salmonella chromosome in mediating the entry of these organisms into cultured mammalian cells and indicate that additional entry pathways are presumably not utilized by these environmental isolates . These results are also consistent with the notion that this region constitutes a pathogenicity island which remains unstable in certain Salmonella serotypes.

Surg Laparosc Endosc, 1997 Apr, 7(2), 137 - 9
Bacteriology of cholelithiasis in infants and children; Klin B et al.; Today, laparoscopic cholecystectomy is rapidly replacing traditional cholecystectomy as the standard treatment of symptomatic cholelithiasis in children . We reviewed the bile cultures and postoperative course of 30 children who underwent laparoscopic cholecystectomy with the aim of establishing a routine policy for perioperative antibiotic treatment and for the management of biliary leak during that procedure . A positive bile culture was found in only one child (Salmonella Group D) . All patients, including six children with intraoperative bile spillage, had a completely normal and uneventful postoperative course . We concluded that the use of preoperative antibiotic treatment should be limited in laparoscopic cholecystectomy in children and is probably not required at all, awaiting proof from a further study . The present study further showed that intraoperative bile spillage is of no clinical significance and can be treated simply with local saline irrigation during the laparoscopic procedure.

Poult Sci, 1997 Apr, 76(4), 654 - 6
Effect of feed withdrawal on the incidence of Salmonella in the crops and ceca of market age broiler chickens; Ramirez GA et al.; Previous research regarding Salmonella contamination in poultry has focused predominantly on cecal and intestinal contamination . Recently, the crop has been implicated as an important source of carcass contamination within the processing plant . In the present study, broiler chickens were orally challenged with 1 x 10(8) cfu S . enteritidis at 6 wk of age . At 7 wk of age, birds were randomly divided into two groups consisting of full access to feed, or total feed withdrawal, 18 h prior to sample collection . At the time of sample collection, crops and ceca were aseptically removed and cultured for the presence or absence of S . enteritidis by enrichment . The incidence of S . enteritidis-positive crops was consistently higher (range: 2.8- to 7.3-fold increases) following feed withdrawal than the incidence in samples collected from full-fed broilers in four experiments . Similarly, the incidence of S . enteritidis isolation was consistently higher (range: 1.4- to 2.1-fold increases) in ceca following feed withdrawal than in samples collected from full-fed broilers in these experiments . In a subsequent experiment, ceca and crops were aseptically collected and cultured for the presence of Salmonella immediately prior to or following 8 h feed withdrawal at a commercial broiler house . Similar to the laboratory experiments, the incidence of Salmonella isolation was significantly (P < 0.01) greater from crops following feed withdrawal (36/100) than from samples obtained immediately prior to withdrawal (19/100) . However, the incidence of Salmonella in the ceca was not significantly higher following feed withdrawal (31/100) than in samples obtained immediately prior to withdrawal (25/ 100) in this field experiment . These studies indicate that feed withdrawal increases the incidence of Salmonella in broiler crops prior to slaughter and provide further evidence that the crop may be an important critical control point for reducing Salmonella contamination of broiler carcasses.

Am J Vet Res, 1997 Apr, 58(4), 334 - 7
Detection of antibodies to Salmonella lipopolysaccharide in muscle fluid from cattle; Hoorfar J et al.; OBJECTIVE: To compare muscle fluid with serum samples for detection of antibodies to Salmonella lipopolysaccharide . SAMPLE POPULATION: Muscle fluid and serum samples from 2 cattle populations: 1 from the island of Bornholm with no history of salmonellosis (n = 39), and the other from the S dublin-enzootic areas of Jutland (n = 144) . PROCEDURE: Salmonella dublin (O:1,9,12), S typhimurium (O:1,4,5,12), and Salmonella O:9-blocking ELISA were used for testing the samples . RESULTS: In the S dublin ELISA, all serum and muscle fluid samples from cattle on the island of Bornholm had OD450 values well below the cutoff value (0.5) . For samples obtained from cattle in the enzootic areas of Jutland, high correlation was found between serum and muscle fluid samples (rs = 0.89, P < 0.001) . In addition, 19% (28/144) of the cattle had ELISA-positive muscle fluid and serum samples; 2% (3/144) had positive results for muscle fluid only, whereas 1 animal had positive results for serum only (kappa = 0.91, P < 0.0001; sensitivity and specificity of 97%) . The same samples had similar significant correlation in the S typhimurium ELISA (rs = 0.88, P < 0.001, kappa = 0.7, P < 0.001; sensitivity of 73% and specificity of 98%) and the O:9-blocking ELISA (rs = 0.49, P < 0.001) . CONCLUSION AND CLINICAL RELEVANCE: Muscle fluid samples taken at slaughter can be used as a practical alternative to serum samples for surveillance of Salmonella infections in cattle.

Appl Environ Microbiol, 1997 Apr, 63(4), 1588 - 93
On-farm monitoring of mouse-invasive Salmonella enterica serovar enteritidis and a model for its association with the production of contaminated eggs; Guard-Petter J et al.; Mice (Mus musculus) captured in henhouses were assessed for the presence of salmonellae in spleens . Of 621 and 526 spleens cultured during the first and second years of collection, 25.0 and 17.9%, respectively, were positive for Salmonella enterica serovar Enteritidis . Contaminated eggs were cultured from nine houses during the first year of sampling, and for eight of these houses, serovar Enteritidis was recovered from the spleens of mice . Rank sum statistical analysis of positive mouse spleens indicated that three overlapping bacterial populations were present . This pattern of infection was repeated when lipopolysaccharide (LPS) variants were used to infect chicks, and the worst infections were associated with isolates producing high-molecular-weight (HMW) LPS . Mouse isolates were capable of producing unprecedented amounts of HMW LPS as indicated by compositional analysis of six isolates that swarmed across 2% agar, which is a type of bacterial migration dependent upon production of HMW LPS . It is suggested that serovar Enteritidis cultured from the spleens of mice caught on farms will detect strains that are enhanced in their ability to contaminate eggs, in part because they are able to produce HMW LPS.

J Mol Evol, 1997 Apr, 44(4), 383 - 97
Amelioration of bacterial genomes: rates of change and exchange; Lawrence JG et al.; Although bacterial species display wide variation in their overall GC contents, the genes within a particular species' genome are relatively similar in base composition . As a result, sequences that are novel to a bacterial genome-i.e., DNA introduced through recent horizontal transfer-often bear unusual sequence characteristics and can be distinguished from ancestral DNA . At the time of introgression, horizontally transferred genes reflect the base composition of the donor genome; but, over time, these sequences will ameliorate to reflect the DNA composition of the new genome because the introgressed genes are subject to the same mutational processes affecting all genes in the recipient genome . This process of amelioration is evident in a large group of genes involved in host-cell invasion by enteric bacteria and can be modeled to predict the amount of time required after transfer for foreign DNA to resemble native DNA . Furthermore, models of amelioration can be used to estimate the time of introgression of foreign genes in a chromosome . Applying this approach to a 1.43-megabase continuous sequence, we have calculated that the entire Escherichia coli chromosome contains more than 600 kb of horizontally transferred, protein-coding DNA . Estimates of amelioration times indicate that this DNA has accumulated at a rate of 31 kb per million years, which is on the order of the amount of variant DNA introduced by point mutations . This rate predicts that the E . coli and Salmonella enterica lineages have each gained and lost more than 3 megabases of novel DNA since their divergence.

J Infect Dis, 1997 Apr, 175(4), 876 - 82
An international outbreak of Salmonella infections caused by alfalfa sprouts grown from contaminated seeds; Mahon BE et al.; An outbreak of Salmonella serotype stanley infections occurred in the United States and Finland in 1995 . The outbreak was investigated through case-control studies in Arizona, Michigan, and Finland; by isolate subtyping; and by tracing and culturing of the implicated food . Alfalfa sprout consumption was the only exposure associated with S . stanley infections in Arizona (matched odds ratio {MOR} = 11.1; 95% confidence interval {CI}, 1.4-513), Michigan (MOR = 5.5; CI, 1.6-23), and Finland (MOR undefined; CI, 4.9-infinity) . US and Finnish patient isolates were a unique outbreak strain distinct from S . stanley isolates not linked to the outbreak . Alfalfa sprouts eaten by patients in 6 US states and Finland were traced to seed shipped by a Dutch shipper . Thus, it was concluded that alfalfa sprouts grown from contaminated seed caused an international outbreak of > or =242 S . stanley infections in > or =17 US states and Finland . This outbreak illustrates a new mechanism through which contamination of fresh produce can cause large, widely dispersed outbreaks.

J Infect Dis, 1997 Apr, 175(4), 871 - 5
Safety and immunogenicity of live oral cholera and typhoid vaccines administered alone or in combination with antimalarial drugs, oral polio vaccine, or yellow fever vaccine; Kollaritsch H et al.; The effects of concomitant administration of antimalarial drugs, oral polio vaccine, or yellow fever vaccine on the immune response elicited by the Vibrio cholerae CVD103-HgR and Salmonella typhi Ty21a live oral vaccines were investigated . Healthy adults were immunized with CVD103-HgR alone or combined with Ty21a . Subjects were randomized to simultaneously receive mefloquine, chloroquine or proguanil, or oral polio or yellow fever vaccine . The vibriocidal antibody seroconversion rate was significantly reduced (P = .008) only in the group that received chloroquine with the CVD103-HgR . The geometric mean vibriocidal antibody titer was significantly decreased in the groups that received chloroquine (P = .001) or mefloquine (P = .02) compared with titers in groups that received CVD103-HgR alone . However, similar immunosuppressive effects were not observed in the groups immunized with Ty21a and CVD103-HgR . Only the concomitant administration of proguanil effected a significant (P = .013) decline in the anti-S . typhi lipopolysaccharide antibody response . These results indicate that chloroquine and proguanil should not be simultaneously administered with the CVD103-HgR and Ty21a vaccine strains, respectively.

J Bacteriol, 1997 Apr, 179(7), 2147 - 53
Identification of additional genes required for O-antigen biosynthesis in Vibrio cholerae O1; Fallarino A et al.; The cloning and expression of the genes encoding the Vibrio cholerae O1 lipopolysaccharide O antigen in a heterologous host have been described previously (P . A . Manning, M . W . Heuzenroeder, J . Yeadon, D . I . Leavesley, P . R . Reeves, and D . Rowley, Infect . Immun . 53:272-277, 1986) . It was thus assumed that all the genes required for O-antigen expression were located on a 20-kb SacI restriction fragment . We present evidence for a number of other as yet undescribed genes that are essential for O-antigen biosynthesis in V . cholerae O1 and that these genes are somehow complemented in Escherichia coli K-12 . The two genes termed Vibrio cholerae rfbV and rfbU are transcribed in the opposite orientation from the rest of the rfb operon, whereas the galE dehydratase and rfbP (Salmonella enterica) homologs, designated ORF35x7 and rfbW, respectively, are transcribed in the same orientation . The evidence presented here, using chromosomal insertion mutants, clearly shows that the three genes now designated rfbV, rfbU, and rfbW appear to be accessory rfb genes and are essential for O-antigen biosynthesis in V . cholerae but that ORF35x7 is not.

J Bacteriol, 1997 Apr, 179(7), 2126 - 31
A virulent isolate of Salmonella enteritidis produces a Salmonella typhi-like lipopolysaccharide; Rahman MM et al.; The lipopolysaccharide (LPS) of Salmonella enteritidis has been implicated as a virulence factor of this organism . Therefore, the LPS from a stable virulent isolate, SE6-E21, was compared with that from an avirulent isolate, SE6-E5 . The LPSs were extracted, and the high-molecular-weight (HMW) LPS was separated from the low-molecular-weight (LMW) LPS for both isolates . Both the HMW and LMW LPSs were characterized by glycosyl composition and linkage analyses . Immunochemical characterization was performed by Western blotting using factor 9 antiserum and using S . typhimurium antiserum which contains factors 1, 4, 5, and 12(2) . In addition, the polysaccharides released by mild acid hydrolysis were isolated and subjected to hydrolysis by bacteriophage P22, which contains endorhamnosidase activity . The resulting oligosaccharides were purified by using Bio-Gel P4 gel permeation chromatography and characterized by nuclear magnetic resonance spectroscopy, fast atom bombardment mass spectrometry (FAB-MS), tandem MS-MS, and matrix-assisted laser desorption time of flight MS . The results show that the HMW LPS O-antigen polysaccharides from both isolates are comprised of two different repeating units, -{-->2)-{alpha-Tyvp-(1-->3)}beta-D-Manp-(1-->4)-alpha-L-R hap-(1-->3)-alpha-D-Galp-(1-->}- (structure I) and {-->2)-{alpha-Tyvp-(1-->3)}beta-D-Manp-(1-->4)-alpha--L-R hap-(1-->3)-{alpha-D-Glcp-(1-->4)}alpha-D-Galp-(1-->}- (structure II) . The LMW LPSs from both isolates contains truncated O-antigen polysaccharide which is comprised of only structure I . In the virulent SE6-E21 isolate, the HMW LPS has a structure I/II ratio of 1:1, while in the avirulent SE6-E5 isolate, this ratio is 7:1 . While the 7:1 ratio represents the published level of glucosylation for S . enteritidis LPS as well as for S . enteritidis LPS purchased from Sigma Chemical Co., the 1:1 ratio found for the virulent SE6-E21 is identical to the high level of glucosylation reported for S . typhi LPS . Thus, the LPS from the virulent SE6-E21 isolate produces an S . typhi-like LPS . Furthermore, the amount of O-antigen polysaccharide in SE6-E21 was twice that in SE6-E5.

Gene, 1997 Mar 25, 188(1), 53 - 61
Genetic map of the virulence plasmid of Salmonella enteritidis and nucleotide sequence of its replicons; Rodriguez-Pena JM et al.; Partial sequencing of a genomic library of the virulence plasmid of Salmonella enteritidis has been used to localize in the restriction map of this plasmid the genetic loci already described in other Salmonella plasmids . The comparison of the vestigial tra region with the corresponding genes in the F plasmid allowed us to define the extent of the deletions that the S . enteritidis plasmid should have suffered . The putative replicons of the plasmid, repB and repC, were isolated and both proved to be functional in Escherichia coli, but repC was segregationally unstable . The nucleotide sequence of repB showed the typical organization of RepFIIA replicons, although the similarity was lower than usual in this group of replicons . The highest homology was found with the replicon of the virulence plasmid pYVe439-80 from Yersinia enterocolitica (72.5%) . Replicon repC also showed a maximum identity of 72.6% with known replicons, namely the RepFIB of pColV-K30 and P307, both virulence plasmids isolated from E . coli . We conclude that the S . enteritidis plasmid could arise from the S . typhimurium plasmid through deletions, and that they are evolutionary distant from other IncFI and IncFII plasmids.

J Comp Neurol, 1997 Mar 24, 379(4), 592 - 602
Central amygdala Fos expression during hypotensive or febrile, nonhypotensive endotoxemia in conscious rats; Tkacs NC et al.; The distribution and time course of Fox expression in neurons in the central nucleus of the amygdala (CeA) were studied in endotoxemic rats in two separate experiments . In each case, the severity of the endotoxin (lipopolysaccharide; LPS) challenge was characterized by using physiological outcome variables, including blood pressure and heart rate . Throughout the rostrocaudal extent of the CeA, extensive Fos staining was found 3 hours after injection with a hypotensive dose of Salmonella enteritidis LPS . Hypotension alone has been reported to induce Fos in the CeA; therefore, the remaining experiments were performed by using a lower dose of Escherichia coli LPS that did not cause hypotension . The nonhypotensive dose of E . coli LPS also induced Fos in large numbers of neurons of the CeA, with peak staining at 2 hours and Fos staining persisting for 6 hours after LPS injection . Tachycardia and fever after LPS also persisted for at least 6 hours . CeA Fos staining during nonhypotensive endotoxemia was predominantly located in the lateral subnucleus, although Fos-stained medial sub-nucleus neurons were also present . Additional forebrain regions that showed persistent Fos staining 6 hours after LPS included the parvocellular paraventricular nucleus of the hypothalamus, the bed nucleus of the stria terminalis, and the medial preoptic area . Forebrain regions that contained Fos-stained nuclei at earlier time points, but not at 6 hours, included the supraoptic nucleus, magnocellular regions of the paraventricular nucleus of the hypothalamus, the subfornical organ, and the organum vasculosum of the lamina terminalis . Few CeA neurons showed Fos staining in rats that were restrained in a ventilated plastic tube . Neurons in the lateral septal nucleus and the medial amygdaloid nucleus, which have numerous Fos-stained nuclei after stressors such as footshock or restraint, did not show Fos staining above control levels after LPS administration . Activation of CeA neurons after intravenous LPS may indicate persistent drive from vagal afferents and may implicate the CeA in the autonomic, neuroendocrine, and/or behavioral responses to this treatment.

J Mol Biol, 1997 Mar 21, 267(1), 118 - 31
Single-chain repressors containing engineered DNA-binding domains of the phage 434 repressor recognize symmetric or asymmetric DNA operators; Simoncsits A et al.; Single-chain (sc) DNA-binding proteins containing covalently dimerized N-terminal domains of the bacteriophage 434 repressor cI have been constructed . The DNA-binding domains (amino acid residues 1 to 69) were connected in a head-to-tail arrangement with a part of the natural linker sequence that connects the N and C-terminal domains of the intact repressor . Compared to the isolated N-terminal DNA-binding domain, the sc molecule showed at least 100-fold higher binding affinity in vitro and a slightly stronger repression in vivo . The recognition of the symmetric O(R)1 operator sequence by this sc homodimer was indistinguishable from that of the naturally dimerized repressor in terms of binding affinity, DNase I protection pattern and in vivo repressor function . Using the new, sc framework, mutant proteins with altered DNA-binding specificity have also been constructed . Substitution of the DNA-contacting amino acid residues of the recognition helix in one of the domains with the corresponding residues of the Salmonella phage P22 repressor c2 resulted in a sc heterodimer of altered specificity . This new heterodimeric molecule recognized an asymmetric, artificial 434-P22 chimeric operator with high affinity . Similar substitutions in both 434 domains have led to a new sc homodimer which showed high affinity binding to a natural, symmetric P22 operator . These findings, supported by both in vitro and in vivo experiments, show that the sc architecture allows for the introduction of independent changes in the binding domains and suggest that this new protein framework could be used to generate new specificities in protein-DNA interaction.

J Mol Biol, 1997 Mar 21, 267(1), 88 - 102
Prevalence of temperature sensitive folding mutations in the parallel beta coil domain of the phage P22 tailspike endorhamnosidase; Haase-Pettingell C et al.; Temperature sensitive mutations fall into two general classes: tl mutations, which render the mature protein thermolabile, and tsf (temperature sensitive folding) mutations, which destabilize an intermediate in the folding pathway without altering the functions of the folded state . The molecular defects caused by tsf mutations have been intensively studied for the elongated tailspike endorhamnosidase of Salmonella phage P22 . The tailspike, responsible for host cell recognition and attachment, contains a 13 strand parallel beta coil domain . A set of tsf mutants located in the beta coil domain have been shown to cause folding defects in the in vivo folding pathway for the tailspike . We report here additional data on 17 other temperature sensitive mutants which are in the beta coil domain . Using mutant proteins formed at low temperature, the essential functions of assembling on the phage head, and binding to the O-antigen lipopolysaccharide (LPS) receptor of Salmonella were examined at high temperatures . All of the mutant proteins once folded at permissive temperature, were functional at restrictive temperatures . When synthesized at restrictive temperature the mutant chains formed an early folding intermediate, but failed to reach the mature conformation, accumulating instead in the aggregated inclusion body state . Thus this set of mutants all have the temperature sensitive folding phenotype . The prevalence of tsf mutants in the parallel beta coil domain presumably reflects properties of its folding intermediates . The key property may be the tendency of the intermediate to associate off pathway to the kinetically trapped inclusion body state.

MMWR Morb Mortal Wkly Rep, 1997 Mar 21, 46(11), 237 - 9
Salmonella serotype Montevideo infections associated with chicks--Idaho, Washington, and Oregon, spring 1995 and 1996; Genotoxic potential of estrogens; Department of Public Health, National Institutes of Health, Bethesda, MD, USAA genotoxicity evaluation of three commonly used estrogens-ethinyl estradiol, cyclotriol and cyclodiol was undertaken using short-term in vitro and in vivo assays . None of the drugs caused significantly increased or decreased number of His+ mutants to appear in the Ames Salmonella assay, either with or without S9 mix or in a modified host-mediated version of this assay . However, the clastogenic potential of these drugs became evident from the increased number or chromosome aberrations and sister chromatid exchanges (SCEs) induced by these drugs in human lymphocyte cultures both in the presence and absence of S9 mix . Increased frequencies of micronuclei and of sister chromatid exchanges in mice confirmed their clastogenic potential.

Int J Food Microbiol, 1997 Mar 3, 34(3), 329 - 33
Comparison of chemical treatments to kill Salmonella on alfalfa seeds destined for sprout production; Beuchat LR; Outbreaks of salmonellosis in the US, Canada and Finland linked to alfalfa sprouts have been attributed to Salmonella stanley in 1995 and Salmonella newport in 1996 . This study was undertaken to compare the efficacy of chemical treatments in killing a mixture of five Salmonella serovars inoculated onto alfalfa seeds . Solutions containing calcium hypochlorite or sodium hypochlorite at concentrations of 1800 and 2000 micrograms/ml active (available) chlorine respectively, as well as 6% hydrogen peroxide or 80% ethanol were effective in reducing Salmonella populations by more than 1000 fold . However, viable Salmonella cells were detected in seeds treated for 10 min in these solutions . The inaccessibility of Salmonella cells in crevices and between the cotyledon and testa of seeds to lethal concentrations of these chemicals are thought to be the reason for the lack of effectiveness.

Int J Food Microbiol, 1997 Mar 3, 34(3), 279 - 92
The determination of efficacy of antimicrobial rinses on turkey carcasses using response surface designs; Bautista DA et al.; Chlorine, lactic acid . TSP (trisodium phosphate) and a commercial phosphate blend (Avgard) were evaluated for their potential bactericidal effects on faecally contaminated turkey carcasses . Carcasses were sprayed for 10 s with each bactericide, at various concentrations and pressure combinations, derived from a response surface central composite design . For all the bactericides, variation in pressure had no significant (P > 0.05) effect in reducing either total or coliform counts . Lactic acid at various concentrations showed a significant effect (P < 0.20) in reducing total and coliform counts . The results indicate that lactic acid at 4.25% (w/w) has the potential for reducing the total microbial load and coliforms by more than 95% . Chlorine, TSP and Avgard concentration did not significantly (P > 0.20) affect the microbial load when compared with a water spray, i.e . no bactericide . Preliminary presumptive testing indicated that lactic acid and Avgard had some effect against Salmonella spp . Chlorine and TSP, irrespective of concentration and pressure, were not effective against Salmonella spp . Overall, these findings suggest that lactic acid was the most effective bactericide for reducing microbial contamination and improving the safety of poultry meat.

Cell Stress Chaperones, 1997 Mar, 2(1), 50 - 9
Hsp70 protects macrophages infected with Salmonella choleraesuis against TNF-alpha-induced cell death; Nishimura H et al.; Hsp70 plays an important role in cytoprotection against tumor necrosis factor (TNF) alpha-mediated cytotoxicity . To investigate the role of Hsp70 in cytoprotection during Salmonella infection, we examined endogenous Hsp70 induction and TNF-alpha production in a monocyte/macrophage line, J774A.1, after infection with a virulent strain of Salm . choleraesuis RF-1 carrying a 50 kb virulent plasmid or the plasmid-cured avirulent strain 31N-1 . Intracellular bacteria progressively increased in J774A.1 cells phagocytosing virulent RF-1 bacteria, whereas such progressive growth was not evident in J774A.1 cells phagocytosing avirulent 31N-1 bacteria . On the contrary, J774A.1 cells infected with virulent RF-1 bacteria expressed less Hsp70 than those infected with avirulent 31N-1 bacteria . The level of TNF-alpha production by J774A.1 infected with virulent RF-1 was much the same as that by J774A.1 infected with avirulent 31N-1 . J774A.1 infected with virulent RF-1 died spontaneously; death was inhibited by the addition of anti-TNF-alpha mAb . Although the frequency of dead J774A.1 with hypodiploid DNA content increased only marginally after infection with avirulent 31N-1, treatment with Hsp70 anti-sense oligonucleotide resulted in a dramatic increase of dead cells in the infected macrophages . Taken together, these results suggest that Hsp70 induced in infected macrophages plays an important role in host defense against Salmonella infection by protecting the macrophages against TNF alpha-induced cell death . Furthermore, cell death due to impaired endogenous Hsp synthesis in the phagocytes implies a novel pathogenic mechanism for virulence of Salm . choleraesuis RF-1.

Mikrobiol Z, 1997 Mar-Apr, 59(2), 73 - 8
{The immunosuppressive activity of filtrates of the culture broth from nonvirulent salmonellae}; Molozhavaia OS et al.; Cultural filtrates (CF) of avirulent Salmonella virchow and Salmonella dublin have been studied for their influence on the delayed type hypersensitivity (DTH) to test-antigen in mice . It is found that i.p . injection of CF inhibits DTH in mice . The immunosuppressive activity is indicated in lipid fraction of CF and it may be removed from CF by the O-specific immunosorbent . It is heat-stable and disappears after phenol or trichloroacetic acid treatment . Gel filtration data evidence for high molecular weight of the active factor . These facts indicate to the connection of immunosuppressive activity with native lipopolysaccharide of avirulent Salmonella.

East Afr Med J, 1997 Mar, 74(3), 193 - 7
Antibiotic resistance pattern of Vibrio cholerae and Shigella causing diarrhoea outbreaks in the eastern Africa region: 1994-1996; Materu SF et al.; Between March 1994 and December 1996, 1797 rectal swabs were transported to the AMREF laboratory from sites in six countries in the eastern Africa region: 1749 were cultured for Vibrio cholerae and 48 for Shigella/Salmonella . Culture, isolation, identification and antibiotic susceptibility testing were performed using standardized techniques . The isolates were categorized as sensitive or resistant based on standardized zones of inhibition . The rate of isolation of V . cholerae from rectal swabs increased progressively from less than 20% to more than 45% between 1994 and 1996, 80-100% of isolates of V . cholerae from Kenya and south Sudan, and 65-90% from Somalia were sensitive to tetracycline, although in 1995 isolates from Mogadishu showed only 44% sensitivity . All isolates from Tanzania and Rwanda were 100% resistant to tetracycline . In Kenya and Somalia, the percentage of isolates sensitive to chloramphenicol and cotrimoxazole reduced markedly from 85% in 1994 to < 10% in 1996 . 100% of isolates from Rwanda and Tanzania were resistant to chloramphenicol and cotrimoxazole while in south Sudan > 70% of isolates were sensitive . Nalidixic acid and erythromycin retained > 75% sensitivity in all areas . Shigella dysenteriae and Shigella flexneri were recovered from dysentery specimens in northern Kenya . Both species showed similar antibiotic sensitivity patterns and were sensitive only to nalidixic acid and furazolidone . Due to variations of resistance patterns within countries in the region, antibiotic sensitivity testing should be performed at the start of an outbreak, and antibiotic use should be restricted to severe cases of V . cholerae and Shigella infection.

East Afr Med J, 1997 Mar, 74(3), 183 - 6
Salmonella serogroups identified from adult diarrhoeal out-patients in Addis Ababa, Ethiopia: antibiotic resistance and plasmid profile analysis; Mache A et al.; Forty five Salmonella strains were isolated from 700 diarrhoeal samples collected from adult diarrhoeal out-patients in Addis Ababa . Among the isolates, serogroup C comprised 31.1%, B 24.4%, S.typhi 15.6%, D 13.3%, A 8.9% and E 6.7% . Among the isolates, 71.1% were resistant to tetracycline, 68.9% to ampicillin, 66.7% to cephalothin, 57.8% to trimethoprim-sulphamethoxazole, 53.9% to kanamycin, 46.7% to chloramphenicol and less than 31.8% of the isolates were resistant to other drugs . Among S.typhi isolates, 28.6% were resistant to chloramphenicol and this shows the emergence of chloramphenicol resistant S.typhi strains in Ethiopia . Gentamicin and polymyxin B were found to be the drugs of choice for cases of salmonellosis including S.typhi . All drug resistant isolates analysed for plasmids contained multiple plasmids ranging in sizes from 1.8 to greater than 21 Kilobases.

Midwifery, 1997 Mar, 13(1), 17 - 23
Adolescents' ideas about the health of the fetus; Edwards G et al.; OBJECTIVE: To determine the preponderance of ideas in adolescents about the relationship between maternal habits and the health of the fetus . DESIGN: Quantitative survey using a precoded questionnaire, the content of which was derived from the transcripts of interviews and the responses to open-form questionnaires . SETTING: North West Region Health Authority area, UK . PARTICIPANTS: 674 adolescents in British National Curriculum Year 10 (age 14/15) from 6 Community Comprehensive Schools . FINDINGS: Most of the adolescents were aware of the dangers to the fetus of alcohol and smoking, including passive smoking . However, they were less aware of the potential hazards during pregnancy of eggs (Salmonella), soft cheeses (Listeria), liver (Vitamin A excess) or handling cats (Toxoplasmosis) . Most of the respondents thought that the optimum time to initiate actions for a healthy pregnancy was when pregnancy had been confirmed, suggesting that the benefits of preconceptual care are not well known . KEY CONCLUSIONS: Adolescents lack knowledge about some of the specific hazards to the fetus of maternal diet and behaviour during pregnancy and are unaware of the importance of the early stages of pregnancy in this context . IMPLICATIONS: There is a need for the provision of education about the importance of a healthy maternal lifestyle before conception and during early pregnancy for adolescents . Midwives may have a proactive role in such education, but should be aware that young people may have specific areas of ignorance and misconceptions which will need addressing.

Biol Chem, 1997 Mar-Apr, 378(3-4), 337 - 43
Interaction of Salmonella phage P22 with its O-antigen receptor studied by X-ray crystallography; Steinbacher S et al.; The O-antigenic repeating units of the Salmonella cell surface lipopolysaccharides (serotypes A, B and D1) serve as receptors for phage P22 . This initial binding step is mediated by the tailspike protein (TSP), which is present in six copies on the base plate of the phage . In addition to the binding activity, TSP also displays a low endoglycolytic activity, cleaving the alpha(1,3)-O-glycosidic bond between rhamnose and galactose of the O-antigenic repeats . The crystal structure of TSP in complex with receptor fragments allowed to identify the receptor binding site for the octasaccharide product of the enzymatic action of TSP on delipidated LPS and the active site consisting of Asp392, Asp395 and Glu359 . The structure comprises a large right-handed parallel beta-helix of 13 turns . These fold independently in the trimer, whereas the N-terminus forms a cap-like structure and the C-terminal parts of the three polypeptide strands merge to a single common domain . In addition, TSP has served as model system for the folding of large, multisubunit proteins . Its folding pathway is influenced by a large number of point mutations, classified as lethal, temperature sensitive or general suppressor mutations, which influence the partitioning between aggregation and the productive folding pathway.

Hepatogastroenterology, 1997 Mar-Apr, 44(14), 529 - 32
Intrahepatic hematoma with secondary Salmonella infection via biliary fistula; Cerwenka H et al.; Usually liver hematoma after blunt trauma is treated conservatively as long as clinically possible, in order to avoid infection via drainage . We report a patient who developed a huge liver abscess after a minor blunt trauma caused by a piece of wood that hit his hepatic region during work with a circular saw . Neither conservative treatment nor percutaneous drainage was successful and intraoperatively a biliary fistula was identified as the route of infection by salmonella . Cholecystectomy (here meaning removal of the salmonella reservoir) and consequent drainage of the gall flow via T-drain were the crucial therapeutic steps and the fistula finally closed after three months . Therapeutic possibilities in the management of blunt liver trauma, and biliary and septic complications are discussed.

Berl Munch Tierarztl Wochenschr, 1997 Mar, 110(3), 96 - 101
{Food hygiene aspects in the production of food fish in fishing}; Hormansdorfer S et al.; The development of the aerob-mesophilic bacteria on epidermis and peritoneum of 68 barbels was determined at 0, 4 and 8 hours after slaughtering . Therefore, one group of 34 animals was stored at 15.3 degrees C, an other equal one at 21.6 degrees C . A change in germ counts per cm2 could be seen in none of the groups during the first 4 hours . However, unrefrigerated carcasses showed an increase of bacteria up to 5-fold between the 4th and 8th hour, whereas in the refrigerated group no change occurred during that time, too . Rinsing the fish after slaughtering resulted in a decrease of the initial bacterial counts by up to 65.4% and so in significantly lower germ loads at the end of the storage time . These results were confirmed by contaminating 24 rainbow trout with Salmonella Infantis artificially . The frequency of detection did not change in refrigerated fish over 8 hours, while nearly doubling in unrefrigerated ones . Moreover, it could be shown that a Salmonella-concentration of only 30 CFU per 100 ml water was sufficient for contaminating fish in detectable grades . The study leads to the conclusion that the storage of instantly slaughtered fish in a common thermobox with freezing elements is suited for preserving its microbiological status for at least 8 hours . The caging of living fish after capture, which must be regarded critically under the aspect of treating animals in a humane way, seems therefore unnecessary.

J Infect, 1997 Mar, 34(2), 133 - 8
Salmonella osteomyelitis in sickle cell disease children in the east end of London; Atkins BL et al.; Five cases of Salmonella osteomyelitis are presented in children with sickle cell disease living in the East End of London . Four of these had involvement of the long bones and one (an infant) presented with hand-foot syndrome . Four required surgical drainage of pus and all required lengthy therapy with antibiotics . Factors contributing to the increased susceptibility of these patients to invasive disease with Salmonella sp . are discussed as are the clinical features, surgical and antibiotic management and possible preventative measures.

Br J Rheumatol, 1997 Mar, 36(3), 333 - 7
HIV infection as a risk factor for septic arthritis; Saraux A et al.; We prospectively studied the demographics, the clinical and diagnostic features, the HIV-1 serostatus and the therapeutic response for all new patients with septic arthritis (SA) admitted to the Department of Internal Medicine of the Centre Hospitalier de Kigali, Rwanda, over a 19 month period . SA was diagnosed in 24 patients (10 male, 14 female), of whom 19 (79%) were HIV-1 seropositive (HIVpos) . Gonococcal arthritis was found in four patients, all HIVpos . Non-gonococcal bacterial arthritis was established in 16 patients, of whom 13 were HIVpos . Causative organisms involved in this group and the corresponding HIV-1 serostatus of the patients were: Staphylococcus aureus: 4; 2 HIVpos . 2 HIVneg: Streptococcus pneumoniae: 4; 4 HIVpos; Salmonella group B: 2; 2 HIVpos; Streptococcus group D: 1; 1 HIVpos; Klebsiella pneumoniae: 1; 1 HIVpos; undetermined: 4; 3 HIVpos; 1 HIVneg . Tuberculous arthritis was presumed in four patients, of whom two were HIVpos . HIV-1-associated SA had a classical acute presentation and an overall good prognosis Compared to a control group consisting of hospitalized patients with malaria as the sole diagnosis, patients with SA were more likely to be infected with HIV-1 (P = 0.005, or 6.3; 95% CI 1.7 22.2) . Prevalence rate estimates of SA among HIVpos and HIVneg patients were 0.5 and 0.25%, respectively (P = 0.38) . We conclude that HIV-1 infection appears as a risk factor for SA among patients hospitalized at the Centre Hospitalier de Kigali, but that SA cannot be used as a predictor for HIV-1 infection for hospitalized patients . SA occurs infrequently and may present at any stage of HIV-1 infection.

Am J Trop Med Hyg, 1997 Mar, 56(3), 254 - 7
Cryptosporidium infections in Mexican children: clinical, nutritional, enteropathogenic, and diagnostic evaluations; Javier Enriquez F et al.; Using an indirect immunofluorescence assay on stool samples, we found a 6.4% prevalence of cryptosporidiosis among 403 children less than five years of age with acute diarrhea in Mexico City over a one-year period . The prevalence was highest (11.4%) during the rainy summer months . Most Cryptosporidium parvum cases occurred in infants less than one year of age . Cryptosporidium parvum was more common in malnourished children (P < 0.05) and in nonbreast-fed infants less than six months of age (P < 0.01) . Neither dwelling characteristics nor the presence of domestic animals at home were associated with C . parvum infection . Enteropathogenic bacteria were found in 26.8% of the children; Escherichia coli, Salmonella, and Shigella being the most frequently identified . None of 100 serum samples tested showed antibodies against human immunodeficiency virus . When compared with immunofluorescence, the acid-fast technique showed a sensitivity of 76.9% and a specificity of 98.9%, with a predictive positive value of 83.3% . It was concluded that 1) monoclonal antibody-based immunofluorescence is a better diagnostic tool than the acid-fast technique, 2) the prevalence of cryptosporidiosis in this population was similar to that of other developing countries, 3) clinical manifestations were nonspecific, and 4) C . parvum was more common in malnourished children and in nonbreast-fed infants.

J Antibiot (Tokyo), 1997 Mar, 50(3), 246 - 55
Correlation of susceptibility and resistance of twenty-five bacterial strains by analysis of MIC database of cephalosporins and oxacephalosporins; Kodama Y et al.; MIC database of 1,407 cephalosporins and oxacephalosporins was utilized to characterize 25 bacterial strains including Gram-positive and Gram-negative bacteria . MIC values were converted to activity rank indices, and distribution patterns of these indices were compared among the bacterial strains . Salmonella enteritidis . No . 11 was the most susceptible bacterium, and the activity against this strain was ascribed to the binding of beta-lactams to the PBPs without any significant barrier to the approach of beta-lactams . Twenty-one strains were assumed to have similar types of PBPs to those of S . enteritidis No . 11 in the binding profile to beta-lactams . Comparison of the scatter diagrams of the activity rank indices revealed two different types of resistances arising from beta-lactamases (9 strains) and outer membrane permeability and/or active efflux (15 strains) . The resistance factor arising from beta-lactamase was affected by the nature of the C-3 substituents of beta-lactams.

Crit Care Med, 1997 Mar, 25(3), 523 - 32
Effects of eicosapentaenoic and gamma-linolenic acid on lung permeability and alveolar macrophage eicosanoid synthesis in endotoxic rats; Mancuso P et al.; OBJECTIVES: Proinflammatory eicosanoids (cyclooxgenase and lipoxygenase metabolites of arachidonic acid) released by alveolar macrophages play an important role in endotoxin-induced acute lung injury . We investigated the effect of prefeeding rats for 21 days with enteral diets that provided the anti-inflammatory fatty acids, eicosapentaenoic acid and gamma-linolenic acid (derived from fish oil and borage oil, respectively), as compared with an n-6 fatty acid-enriched diet (corn oil) on the following: a) lung microvascular protein permeability, arterial blood pressure, and platelet and white blood cells in a model of endotoxin-induced acute lung injury; b) alveolar macrophage prostaglandin and leukotriene synthesis; and c) liver and alveolar macrophage phospholipid fatty acid composition . DESIGN: Prospective, randomized, controlled, double-blind study . SETTING: Research laboratory at a university medical center . SUBJECTS: Male Long-Evans rats, weighing 250 g . INTERVENTIONS: Rats were randomized into four dietary treatment groups and fed nutritionally complete diets (300 kcal/kg/day), containing 55.2% of the total calories from fat with either 97% corn oil, 20% fish oil, 20% fish and 5% borage oil, or 20% fish and 20% borage oil for 21 days . On day 22, lung microvascular protein permeability, mean arterial pressure, and platelet and white blood cell counts were determined for 2 hrs after an intravenous injection of Salmonella enteritidis endotoxin (10 mg/kg) . In a second group of prefed rats, the phospholipid fatty acid composition was determined in liver and alveolar macrophages . Alveolar macrophages were harvested by bronchoalveolar lavage and stimulated in vitro with a calcium ionophore (A23187), and the concentrations of leukotrienes B4 and B5, thromboxane A2, prostaglandin E2, and 6-keto-prostaglandin F1 alpha were measured in a third group of prefed rats . MEASUREMENT AND MAIN RESULTS: Lung permeability was greatest with corn oil and was significantly attenuated with 20% fish oil and 20% fish and 5% borage oil, and this effect approached significance with 20% fish and 20% borage oil (p = .06) . The early and late hypotensive effects of endotoxin were attenuated with 20% fish oil, 20% fish and 5% borage oil, and 20% fish and 20% borage oil, as compared with corn oil . Concentrations of leukotriene B4, prostaglandin E2, and thromboxane B2 released from A23187-stimulated alveolar macrophages were significantly lower with 20% fish oil and 20% fish and 20% borage oil, as compared with corn oil . The increase in lung microvascular protein permeability with 20% fish and 20% borage oil was not significantly different than the lung microvascular protein permeability that was found in animals receiving 20% fish oil (p = .20) and 20% fish and 5% borage oil (p = .31) . Alveolar macrophage and liver phospholipid concentrations of arachidonic acid were lower, and the concentrations of eicosapentaenoic acid and docosahexaenic acid were higher, with 20% fish oil, and 5% borage oil, and 20% fish and 20% borage oil, as compared with corn oil . Dihomo-gamma-linolenic acid, the desaturated and elongated intermediate of gamma-linolenic acid, was increased with 20% fish and 20% borage oil, as compared with 20% fish oil and 20% fish and 5% borage oil . CONCLUSIONS: The severity of pulmonary microvascular protein permeability and the degree of hypotension were reduced with fish or fish and borage oil diets, as compared with corn oil, in endotoxic rats . The reduced synthesis of the proinflammatory arachidonic acid-derived mediators, leukotriene B4, thromboxane B2, and prostaglandin E2 from stimulated alveolar macrophages was indicative of a decrease in arachidonic acid and an increase in eicosapentaenoic acid and docosahexaenoic acid in cell membrane phospholipids.

Can J Cardiol, 1997 Mar, 13(3), 299 - 301
Salmonella endocarditis of a ventricular aneurysm: a case report and review of the literature; Amyot R et al.; A 63-year-old man with salmonella endocarditis of a ventricular aneurysm is presented . The patient had a documented apical aneurysm with mural thrombus and left ventricular dysfunction following a previous myocardial infarction . His condition was unresponsive to maximal medical therapy and was cured by surgery . A review of the English-language literature revealed that only two other published cases of nonvalvular salmonella endocarditis resulted in patient survival . This report underscores the importance of suspecting a cardiovascular origin in cases of salmonella bacteremia to avoid delay in diagnosis and surgical intervention in this deadly condition.

Clin Infect Dis, 1997 Mar, 24(3), 506 - 10
Epidemiology of an unusually prolonged outbreak of typhoid fever in Terrassa, Spain; Xercavins M et al.; An unusually prolonged outbreak of typhoid fever, from 1988 to 1994, in Terrassa (Barcelona, Spain), was caused by a casual food handler who was a carrier . The pattern of this outbreak suggested intermittent low-level exposure to Salmonella typhi . We found 70 patients with S . typhi infections, 52 of whom were available for study . Medical records were reviewed and patients were interviewed with use of a standard questionnaire . Phage typing and pulsed-field gel electrophoresis (PFGE) for strain subtyping were used to confirm the epidemiological data . The 27 outbreak strains shared the same phage type and the same PFGE pattern . Four sporadic strains shared the same phage type as the outbreak strain . PFGE was found to be useful for differentiating strains for epidemiological purposes.

Dtsch Tierarztl Wochenschr, 1997 Mar, 104(3), 118 - 9
Salmonella enteritidis colonization in turkey poults; Hafez HM et al.; An experimental trial on the colonization of two Salmonella enteritidis strains (phage types 4 and 8) originating from meat turkey flocks, were carried out . Three-day old poults were inoculated orally with approximately 10(6) cfu/bird (one group with PT8 and the other with PT4) . clinical signs were not observed in any of the groups . The total reisolation rates from cloacal swabs in birds inoculated with PT4 was higher than from birds inoculated with PT8 . The inoculated strains could also be detected in contact birds . Examination of internal organs 21 days p.i . revealed higher isolation rates in the group infected with PT4 than with PT8 . The results indicate that both phage types of S . enteritidis were able to colonize the intestinal tract and the internal organs of turkey poults . However, the colonization and duration of shedding differed between the two phage types . This may be due to the fact that PT8 strain used was free from the S . e . virulence plasmid 37 MDa.

Vet Microbiol, 1997 Mar, 54(3-4), 375 - 83
Potential virulence determinants of Salmonella serovars from poultry and human sources in Spain; Carraminana JJ et al.; A total of 173 Salmonella strains of different serovars isolated during 1992 from poultry and human sources in Zaragoza (NE Spain) were investigated for potential virulence factors . Parameters studied included production of aerobactin, enterobactin, colicin (including colicin V) and hemolysin, serum resistance against serum from man, sheep, cattle and chicken, binding of Congo red and crystal violet, auto-agglutination and calcium dependency at 37 degrees C and double colony morphology . Preliminary studies showed tests with completely negative results (colicins and hemolysin production, double colony morphology, auto-agglutination and calcium dependency at 37 degrees C) and tests with completely positive results (enterobactin production and binding of Congo red) . The tests with variability of results were production of aerobactin, serum resistance and crystal violet binding . Aerobactin production was detected in 80% of Salmonella strains of clinical human origin and in 30% of Salmonella strains isolated from healthy slaughtered chickens . Sixty-five per cent of patient isolates were human serum resistant, 73% were ovine serum resistant, 85% were bovine serum resistant and 98% were chicken serum resistant . The percentages of poultry isolates serum resistant were 61, 86, 60 and 89% in human, ovine, bovine and chicken serum, respectively . Crystal violet binding was detected in 22.5% of Salmonella isolates from human origin and in 32.3% of Salmonella strains from poultry origin . This study can form a marker for the prevalence of strains with various characteristics (production of aerobactin, serum resistance and crystal violet binding) for comparison in future epidemiological studies . Furthermore, the data of this work suggested that strains causing enteric salmonellosis in man are partially identical to strains isolated from carrier broilers.

J Physiol Pharmacol, 1997 Mar, 48(1), 111 - 7
Fe(2+)-initiated chemiluminescence in rats with high hemoglobin-oxygen affinity during fever; Zinchuk V et al.; The effect of high hemoglobin-oxygen affinity (HOA) on chemiluminescence initiated by Fe2+ was studied in rat plasma and red cell ghosts during fever . The high HOA was induced by daily ingestion of sodium cyanate with drinking water for 8 weeks . Rats with high or normal HOA received i.p . lipopolysaccharide Salmonella typhi (LPS) . The half-saturation oxygen pressure (p50) after 240 min of fever was 23.3 +/- 0.7 in cyanate-treated rats comparing with 30.4 +/- 0.4 Torr in the group received placebo . The maximal value of initiated chemiluminescence rose in plasma and red cell ghosts of rats with normal HOA by 26.5 and 27.5%, respectively, and in rats with modified HOA by 17.1 and 23.8%, respectively . The antioxidant activity of plasma and red cell ghosts decreased under high HOA to a less extent . These investigations show that the lowering of oxygen flux to tissues due to hemoglobin carbamylation may decrease the production of free radicals in rats during fever.

J Physiol Pharmacol, 1997 Mar, 48(1), 81 - 8
A comparison of febrile responses induced by LPS from E . coli and S . abortus in unrestrained rats placed in a thermal gradient; Bodurka M et al.; The purpose of our study was a comparison of pyrogenic and behavioural effects of Escherichia coli (E.coli) and Salmonella abortus (S.abortus) endotoxins in unrestrained, freely moving Wistar rats, placed in a thermal gradient and having an easy access to ambient temperatures within a range 5-40 degrees C . Hypothalamic and chosen by the rats ambient temperatures as well as locomotor activity were recorded before and after intraperitoneal injection of 1 mg/kg lipopolysaccharide from E . coli or from S . abortus . Control animals were injected with pyrogen-free saline . Both endotoxins induced warm-seeking behaviour which was accompanied by biphasic fever . Locomotor activity of LPS-injected rats was reduced . S . abortus-induced fever peaked at 100th minute (reaching 37.5 +/- 0.2 degrees C) and at 250th minute (reaching 38.1 +/- 0.1 degrees C) . Respective data for E . coli fever were: 170th minute (when hypothalamic temperature reached 37.6 +/- 0.3 degrees C) and 430th minute (with hypothalamic temperature of 38.6 +/- 0.1 degrees C) . Comparing to S . abortus-generated fever both peaks of E . coli LPS-induced fever were significantly delayed (p < 0.05) . A limited structural variability of lipid A from both bacteria is likely to be responsible for the difference in fever timing recorded in this study.

Br Poult Sci, 1997 Mar, 38(1), 59 - 65
Antibacterial activity of formic and propionic acids in the diet of hens on Salmonellas in the crop; Thompson JL et al.; 1 . The inclusion of formic and propionic acids in the form of Bio-Add to the food of hens made no difference to the pH of the intestinal tract, but resulted in higher concentrations of these acids in the contents of the crop and gizzard . 2 . Organic acids in the crop contents were bactericidal for Salmonella serotype Enteritidis PT4 in vitro, and also caused sub-lethal damage because fewer cells were recovered on selective salmonella media (brilliant green phenol red agar) than on non-selective media (nutrient agar) . 3 . Inclusion of Bio-Add in the food at 12g/kg may reduce the number of lactic acid-producing bacteria in the crop, and hence the amount of naturally produced organic acids.

Rinsho Byori, 1997 Mar, 45(3), 242 - 8
{Current status of gastrointestinal infection in Japan--with special reference to enterohaemorrhagic Escherichia coli infection}; Kudoh Y; The annual incidence of gastrointestinal infections such as bacillary dysentery, typhoid fever and paratyphoid fever has declined markedly since the early 1960s . However, in parallel with the increase of international travel, the incidence of imported cases from abroad has recently tended to increase . Moreover, similar to North America and Europe, food-borne infections such as Salmonella food poisoning due to serovar Enteritidis and enterohaemorrhagic Escherichia coli infection has increased dramatically recently . In this paper, the current trend of gastrointestinal infections in Japan was discussed from the epidemiologic and bacteriologic view points.

Lett Appl Microbiol, 1997 Mar, 24(3), 217 - 20
Immunomagnetic separation for enhanced flagellar antigen phase inversion in salmonella; Davies RH et al.; Immunomagnetic separation (IMS) was used to reduce delays in serotyping caused by slow flagellar phase inversion of diphasic salmonellas . Some 375 strains of 11 salmonella serotypes were examined using IMS . The mean time for successful flagellar phase inversion was reduced from 4.3 (range 1-18) d to 1.0 (range 1-3) d using the IMS method, and in a further experiment phase inversion was achieved within 8 h in 112 of a further 117 strains representing four salmonella serotypes.

Pediatr Infect Dis J, 1997 Mar, 16(3), 277 - 83
Clinical definition for invasive Salmonella infection in African children; Cheesbrough JS et al.; BACKGROUND: Invasive salmonellosis is common among children in tropical Africa, typically presenting as a nonspecific febrile illness that is difficult to distinguish clinically from malaria . This study examines the performance of a clinical definition devised to aid its recognition among children ages 1 to 15 years presenting to a mission hospital in rural Zaire . METHODS: Invasive salmonellosis was defined by: (1) illness requiring admission to hospital in the opinion of an experience pediatrician; (2) history of fever for 5 or more days; (3) no focus of infection on clinical examination; and (4) negative or only scanty positive thick film for malarial parasites . Children fulfilling all these criteria were treated with ciprofloxacin after culture of blood and feces . The primary outcome measure was blood culture-confirmed salmonellosis . Secondary measures were final clinical diagnosis and serologic evidence of recent salmonellosis . RESULTS: Of 120 children fulfilling the definition, 55 (46%) were bacteremia; in 46 (38%) Salmonella species were isolated . In the majority of the nonbacteremic children no definite cause for the fever could be found . Salmonella serology supported invasive salmonellosis as the diagnosis in 62% of the nonbacteremic children . CONCLUSION: Salmonella serology suggested that invasive salmonellosis without detectable bacteremia was common . The addition of blood culture-proved and serologically diagnosed cases indicates that the definition has a specificity of at least 60%.

J Bacteriol, 1997 Mar, 179(6), 1985 - 91
Comparative genetics of the inv-spa invasion gene complex of Salmonella enterica; Boyd EF et al.; The chromosomal region containing the Salmonella enterica pathogenic island inv-spa was present in the last common ancestor of all the contemporary lineages of salmonellae . For multiple strains of S . enterica, representing all eight subspecies, nucleotide sequences were obtained for five genes of the inv-spa invasion complex, invH, invE, invA, spaM, and spaN, al of which encode proteins that are required for entry of the bacteria into cultured epithelial cells . The invE, invA, spaM, and spaN genes were present in all eight subspecies of S . enterica, and for invE and invA and their products, levels of sequence variation among strains were within the ranges reported for housekeeping genes . In contrast, the InvH, SpaM, and SpaN proteins were unusually variable in amino acid sequence . Furthermore, invH was absent from the subspecies V isolates examined . The SpaM and SpaN proteins provide further evidence of a relationship (first detected by Li et al . {J . Li, H . Ochman, E . A . Groisman, E . F . Boyd, F . Solomon, K . Nelson, and R . K . Selander, Proc . Natl . Acad . Sci . USA 92:7252-7256, 1995}) between the cellular location of the products of the inv-spa genes and evolutionary rate, as reflected in the level of polymorphism within S . enterica . Invasion proteins that are membrane bound or membrane associated are relatively conserved in amino acid sequence, whereas those that are exported to the extracellular environment are hypervariable, possibly reflecting the action of diversifying selection.

Shock, 1997 Mar, 7(3), 200 - 5
Molsidomine increases endotoxic survival and decreases cytokine production; Kumins NH et al.; We hypothesized that nitric oxide (NO) may exert feedback regulatory control over cytokine production and improve survival in endotoxin (ETX) shock . To test this hypothesis, we evaluated the pre-endotoxin effect of the NO donor molsidomine (MOL) on circulating tumor necrosis factor (TNF), interleukin (IL)-1, and IL-6 levels, the production of these cytokines in the perfused liver, and endotoxic lethality in mice . Male BDF mice weighing 28-32 g were administered either 100 mg/kg MOL or saline (SAL) i.p . Thirty minutes later, the mice received either 50 mg/kg Salmonella enteriditis ETX or SAL i.p . Mice were killed at 90 min after ETX or SAL, for either the determination of plasma cytokine levels by enzyme-linked immunosorbent assays or for use in the perfused liver assessment of cytokine production . MOL treatment significantly reduced the post-ETX circulating levels of TNF to 84%, IL-1 to 65%, and IL-6 to 56%, as compared with SAL-treated ETX controls . Endotoxic livers from MOL-pretreated mice produced 82% less TNF, 88% less IL-1, and 54% less IL-6 over a 2 h perfusion, as compared with SAL-treated ETX controls . MOL pretreatment also decreased lethality in ETX shock from 90 to 50% (p < .05) . Therefore, NO may provide a beneficial effect during sepsis by inhibiting hepatic cytokine production, and thus providing survival benefits.

J Pediatr, 1997 Mar, 130(3), 394 - 9
Septicemia caused by Salmonella infection: an overlooked complication of sickle cell disease; Wright J et al.; OBJECTIVES: To describe the characteristics of salmonella infections in sickle cell disease and to compare the features of osteomyelitis and those with bacteremia/septicemia without obvious bone changes . To search for risk factors for osteomyelitis, and to draw attention to the frequency and significance of salmonella bacteremia/septicemia . STUDY DESIGN: A retrospective review of all salmonella isolations from the blood, pus, or aspirates during a 22-year period . SETTING: The sickle cell clinic at the University Hospital of the West Indies, Kingston, Jamaica . SUBJECTS: Patients with all genotypes of sickle cell disease . Incidence data and the frequency of associated cholelithiasis were derived from the cohort study based on follow-up of all children detected by neonatal screening . MAIN OUTCOME MEASURES: Osteomyelitis and bacteremia/septicemia . RESULTS: Of 55 patients with salmonella infections, 25 initially had osteomyelitis and 27 had bacteremia/septicemia . Three of the first group later had bacteremias for a total of 30 episodes of bacteremia/septicemia, and 4 of the second group later had osteomyelitis for a total of 32 episodes of osteomyelitis . The incidence of salmonella infection was 8.6% by 15 years, and 96% of infections occurred before the age of 10 years . Preceding episodes of avascular necrosis of bone were more frequent (p < 0.006) in patients with osteomyelitis . Patients with osteomyelitis were not more prone to gallstones . High fever (temperature > or = 40 degrees C or 104 degrees F) occurred in 41%, and occasionally marked bone marrow suppression mimicked the aplastic crisis . Twenty Salmonella serotypes were isolated; Salmonella enteritidis accounted for 36% of infections, but no serotype difference occurred between those with osteomyelitis and those with bacteremia/septicemia . There were no deaths in the 32 patients with osteomyelitis, but 7 (23%) of 30 patients with septicemia died . CONCLUSIONS: Anti-salmonella prophylaxis requires assessment in the management of bone necrosis . Anti-salmonella agents may be indicated in undiagnosed septic conditions in sickle cell disease pending culture results.

What Is Biotechnology?, What Is Genetics?, What Is Cell Biology?, What Is MIC?, What Is Bioremediation?, c, Bacteriology, n, Microbe, e, Microorganism, i, Bacterium, c, Microbes, r, Escherichia coli, c, Staphylococcus, i, Escherichia coli, i, Pseudomonas aeruginosa, c, Staphylococcus aureus, r, Enterobacteriacea, n, Nitrifying, e, Bacillus, a, Salmonella, i, Meningococcus, s, Escherichia coli, n, Vibriosis, i, Ciprofloxacin, e, Microbiological, i, Microbiological, a, Cell cultures, c, Cell cultures, i, Candida albicans, r, Escherichia coli, i, Microorganism, n, Proteus

Scientific Publications - Work Done by Microbiology Reader Bioscreen C
Agricultural Microbiology Anaerobic Microbiology Antimicrobial Susceptibility Artificial Atmosphere Bioassay of Antibiotics Biofilm Microbiology Bioreactor Technology Biotechnology Cell Biology Clinical Microbiology Environmental Microbiology Experiments with Yeast	Fermentation Food Microbiology Functional Genomics Gene Technology Growth Media Development Growth Rate and Lag Time Industrial Microbiology Medical/Pharmaceutical Field Microbiological Assay Microbiological Research Microbiology of Cosmetics go to a specific theme...	Military Microbiology Molecular Microbiology Mutagenicity and Genotoxicity Oral Microbiology Patents Postantibiotic Studies Soil Microbiology Spore Microbiology Veterinary Microbiology Waste/Wastewater Treatment Water Microbiology Wine Microbiology

� 2005 Transgalactic Ltd (manufacturer of Bioscreen C software) | Privacy Statement | P.O. Box 1393, 00101 Helsinki, Finland, phone: +358 9 85172920, fax: +358 9 8749481, e-mail: microbiology@bionewsonline.com

Last modified: May 25, 2005