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| Infect Immun, 2003 Dec, 71(12), 6808 - 19 Characterization and development of T-Cell immune responses in B-cell-deficient (Igh-6(-/-)) mice with Salmonella enterica serovar Typhimurium infection; Ugrinovic S et al.; Infection of mice with Salmonella enterica serovar Typhimurium induces strong Th1 T-cell responses that are central to the control of the infection . In the present study, we examined the role of B cells in the development of Th1 T-cell responses to Salmonella by using gene-targeted B-cell-deficient mice (Igh-6(-/-) mice) . The development of Th1 T-cell responses in Igh-6(-/-) mice was impaired in the early stage of a primary infection . This impairment persisted throughout the course of the disease . The ability of T cells to produce the Th1 cytokine gamma interferon and the frequency at which they did so were lower in Igh-6(-/-) mice than in control mice . We also observed a transient switch toward Th2 cytokine production in Igh-6(-/-) mice . Thus, B cells are important for the induction of protective Th1 T-cell responses in the early phase of a Salmonella infection . Activated B cells express high levels of major histocompatibility complex and costimulatory molecules and are nearly as effective as dendritic cells in their antigen-presenting cell (APC) activity . However, their importance as APCs in infection and their role in initiating and/or maintaining T-cell responses are unknown . Here, we show that B cells upregulate costimulatory molecules upon in vitro stimulation with S . enterica serovar Typhimurium and that they can present Salmonella antigens to Salmonella-specific CD4(+) T cells . Our results show that B cells are important for the development of T-cell responses in the early stage of a Salmonella infection and that this property may be due to their ability to present antigens to T cells. Infect Immun, 2003 Dec, 71(12), 6734 - 41 Association of Salmonella enterica serovar enteritidis yafD with resistance to chicken egg albumen; Lu S et al.; Salmonella enterica serovar Enteritidis is a major cause of food-borne diseases in industrialized countries . The incidence of S . enterica serovar Enteritidis infections has increased substantially in recent decades, and S . enterica serovar Enteritidis is now one of the leading serovars of Salmonella in the United States . A unique epidemiological characteristic of S . enterica serovar Enteritidis is its association with chicken shell eggs, since approximately 80% of all human gastrointestinal diseases can be traced to contaminated egg products . Eggs are contaminated when bacteria from reproductive tissues of infected hens are packaged into the eggs and persist inside the hostile egg albumen environment . Therefore, resistance to egg albumen is an important aspect in the transmission of S . enterica serovar Enteritidis . We identified a gene, yafD from S . enterica serovar Enteritidis, whose overexpression conferred upon S . enterica serovar Typhimurium enhanced resistance to egg albumen, while disruption of this gene in S . enterica serovar Enteritidis rendered the organism more susceptible to egg albumen . YafD is homologous to members of an exonuclease-endonuclease-phosphatase family, including some enzymes involved in DNA repair . Furthermore, we discovered that egg albumen has nuclease activities and uses both circular and linear DNA as substrates . We propose that YafD provides a survival advantage to S . enterica serovar Enteritidis in eggs by repairing DNA damage caused by egg albumen and that it may be one of the biologic determinants that contribute to the epidemiological association of S . enterica serovar Enteritidis with egg products. Antimicrob Agents Chemother, 2003 Dec, 47(12), 3840 - 5 GeneHunter, a transposon tool for identification and isolation of cryptic antibiotic resistance genes; Salipante SJ et al.; GeneHunter is a transposon tool designed for the experimental activation and identification of silent antibiotic resistance genes . The method permits the identification of novel resistance genes that lack previously identified homologues . Using Salmonella enterica serovar Typhimurium strain LT2 as a test organism for the in vivo version of the GeneHunter method, we were able to activate, clone, and identify two cryptic antibiotic resistance genes, the aminoglycoside acetyltransferase aac(6')-Iaa and the probable Mar-A regulon activator rma . Because the method requires being able to electroporate the host with an efficiency of at least 10(10) transformants per microgram, the in vivo method is not applicable to most microorganisms . We therefore developed an in vitro transposition method, showed that it can also recover the cryptic rma gene from S . enterica serovar Typhimurium strain LT2, and showed that it is generally applicable to a variety of microorganisms by using it to recover a cryptic metallo-beta-lactamase gene from the gram-positive organism Bacillus cereus . It is anticipated that the GeneHunter method will be used to identify potential resistance genes during the development and testing of novel antibiotics, new variants of existing antibiotics, and drug inhibitor combinations. Antimicrob Agents Chemother, 2003 Dec, 47(12), 3743 - 9 Fusidic acid-resistant mutants of Salmonella enterica serovar Typhimurium with low fitness in vivo are defective in RpoS induction; Macvanin M et al.; Mutants of Salmonella enterica serovar Typhimurium resistant to fusidic acid (Fusr) have mutations in fusA, the gene encoding translation elongation factor G (EF-G) . Most Fusr mutants have reduced fitness in vitro and in vivo, in part explained by mutant EF-G slowing the rate of protein synthesis and growth . However, some Fusr mutants with normal rates of protein synthesis still suffer from reduced fitness in vivo . As shown here, Fusr mutants could be similarly ranked in their relative fitness in mouse infection models, in a macrophage infection model, in their relative hypersensitivity to hydrogen peroxide in vivo and in vitro, and in the amount of RpoS production induced upon entry into the stationary phase . We identify a reduced ability to induce production of RpoS (sigmas) as a defect associated with Fusr strains . Because RpoS is a regulator of the general stress response, and an important virulence factor in Salmonella, an inability to produce RpoS in appropriate amounts can explain the low fitness of Fusr strains in vivo . The unfit Fusr mutants also produce reduced levels of the regulatory molecule ppGpp in response to starvation . Because ppGpp is a positive regulator of RpoS production, we suggest that a possible cause of the reduced levels of RpoS is the reduction in ppGpp production associated with mutant EF-G . The low fitness of Fusr mutants in vivo suggests that drugs that can alter the levels of global regulators of gene expression deserve attention as potential antimicrobial agents. FEMS Microbiol Lett, 2003 Nov 21, 228(2), 225 - 31 Reduced amounts of LPS affect both stress tolerance and virulence of Salmonella enterica serovar Dublin; Thomsen LE et al.; Signature-tagged mutagenesis (STM) is a widely used technique for identification of virulence genes in bacterial pathogens . While this approach often generates a large number of mutants with a potential reduction in virulence a major task is subsequently to determine the mechanism by which the mutations influence virulence . Presently, we have characterised a Salmonella enterica serovar Dublin STM mutant that, in addition to having reduced virulence, was also impaired when growing under various stress conditions . The mutation mapped to the manC (rfbM) gene of the O-antigen gene cluster involved in O-antigen synthesis . The O-antigen is a component of the lipopolysaccharide (LPS) forming a unique constituent of the outer membrane of Gram-negative bacteria . While mutations in the O-antigen genes usually eliminate the entire O-antigen side chain we found that the transposon mutant produced intact O-antigen, however, the mutation reduced the amount of LPS. Cell, 2003 Oct 31, 115(3), 333 - 42 Temporal regulation of salmonella virulence effector function by proteasome-dependent protein degradation; Kubori T et al.; Salmonella enterica invasion of host cells requires the reversible activation of the Rho-family GTPases Cdc42 and Rac1 by the bacterially encoded GEF SopE and the GAP SptP, which exert their function at different times during infection and are delivered into host cells by a type III secretion system . We found that SopE and SptP are delivered in equivalent amounts early during infection . However, SopE is rapidly degraded through a proteosome-mediated pathway, while SptP exhibits much slower degradation kinetics . The half-lives of these effector proteins are determined by their secretion and translocation domains . Chimeric protein analysis indicated that delivery of SptP into host cells by the SopE secretion and translocation domain drastically shortened its half-life . Conversely, delivery of SopE by the SptP secretion and translocation signals significantly increased its half-life, resulting in persistent actin cytoskeleton rearrangements . This regulatory mechanism constitutes a remarkable example of a pathogen's adaptation to modulate cellular functions. Eur J Immunol, 2003 Dec, 33(12), 3275 - 83 Cutaneous lymphocyte antigen expression on human effector B cells depends on the site and on the nature of antigen encounter; Kantele A et al.; In contrast to T cells, information on skin-homing B cells expressing the cutaneous lymphocyte antigen (CLA) is sparse . CLA expression on human B cells was investigated among circulating immunoglobulin-secreting cells (ISC) and among antigen-specific antibody-secreting cells (ASC) elicited by parenteral, oral or rectal primary immunization, or by parenteral or oral secondary immunization with Salmonella typhi Ty21a . CLA expression was examined by combining cell sorting with an enzyme-linked immunospot assay . Among all ISC, the proportion of CLA(+) cells was 13-21% . Parenteral immunization induced antigen-specific ASC of which 13% were CLA(+), while oral and rectal immunizations were followed by only 1% of CLA(+) ASC (p<0.001) . Oral re-immunization was followed by an up-regulation of CLA (34-48%) regardless of the route of priming . Parenteral re-immunization elicited ASC of which 9-14% were CLA(+) . In conclusion, the expression of CLA on human effector B cells depends on the site of antigen encounter: intestinal stimulation elicits cells with no CLA, while parenteral encounter elicits significant numbers of CLA(+) cells . Even though primary antigen encounter in the intestine failed to stimulate CLA expression, up-regulation of CLA was found upon intestinal antigen re-encounter . These findings may be of relevance in the pathogenesis of some cutaneous disorders. J Biol Chem, 2004 Feb 13, 279(7), 5667 - 75 Epub 2003 Nov 21. Identification of conserved domains in Salmonella muenchen flagellin that are essential for its ability to activate TLR5 and to induce an inflammatory response in vitro; Murthy KG et al.; The bacterial surface protein flagellin is widely distributed and well conserved among distant bacterial species . We and other investigators have reported recently that purified flagellin from Salmonella dublin or recombinant flagellin of Salmonella muenchen origin binds to the eukaryotic toll receptor TLR5 and activates the nuclear translocation of NF-kappaB and mitogen-activated protein kinase, resulting in the release of a host of pro-inflammatory mediators in vitro and in vivo . The amino acid sequence alignment of flagellins from various Gram-negative bacteria shows that the C and N termini are well conserved . It is possible that sequences within the N and C termini or both may regulate the pro-inflammatory activity of flagellin . Here we set out to map more precisely the regions in both termini that are required for TLR5 activation and pro-inflammatory signaling . Systematic deletion of amino acids from either terminus progressively reduced eukaryotic pro-inflammatory activation . However, deletion of amino acids 95-108 (motif N) in the N terminus and 441-449 (motif C) in the C terminus abolished pro-inflammatory activity completely . Site-directed mutagenesis analysis provided further evidence for the importance of motifs N and C . We also present evidence for the functional role of motifs N and C with the TLR5 receptor using a reporter assay system . Taken together, our results demonstrate that the pro-inflammatory activity of flagellin results from the interaction of motif N with the TLR5 receptor on the cell surface. Lett Appl Microbiol, 2003, 37(5), 421 - 3 Presence of Listeria and Salmonella spp . in retail chicken in Northern Ireland; Soultos N et al.; AIMS: Retail packs of fresh chicken in Northern Ireland were sampled to determine the frequency with which they were contaminated with Salmonella and Listeria spp . METHODS: Packs of chicken were chosen from supermarkets ensuring a diverse range of EU producer codes were sampled . Salmonellas were isolated using BS EN 12824: 1998 methodology, biotyped and serotyped whilst Listeria spp . were isolated based on EN ISO 11290-1: 1996 procedures and identified using a multiplex PCR system utilizing genus and species specific primers . SIGNIFICANCE AND IMPACT OF THE STUDY: Only three of 205 samples yielded Salmonella spp . indicating that measures undertaken by the poultry industry to control this pathogen have apparently been successful . However, Listeria spp . were present in 38 of 80 samples tested (48%) and 14 (18%) yielded Listeria monocytogenes . Thus Salmonella controls do not markedly affect this pathogen and retail packs of raw chicken must be considered a potential source of L . monocytogenes, and appropriate precautions taken to prevent infection. Lett Appl Microbiol, 2003, 37(5), 405 - 9 Assessment of the presence of Salmonella spp . in Egyptian dairy products using various detection media; Nassib TA et al.; AIMS: To make a preliminary assessment of the incidence of Salmonella in Egyptian dairy products, and to investigate the effectiveness of various protocols for the detection of the pathogen in these products . METHODS AND RESULTS: Samples of milk and related dairy products were randomly collected from local markets and examined for the presence of Salmonella . While most samples were free of the organism, isolates of Salmonella enterica subsp . enterica serovar Typhimurium PT 8 could be recovered from 'matared' cream specimens . These isolates were susceptible to antibiotics usually used to challenge infections caused by Salmonella . A combination of buffered peptone water, Muller-Kauffman tetrathionate broth, and brilliant green phenol red agar gave the best results for the detection of the pathogen . Selenite-cystine broth and Hektoen enteric agar were ineffective as an enrichment and a plating medium, respectively, in the isolation of Salmonella . A modified identification strategy that reduces the burden of serological testing of presumptive isolates is proposed . CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: 'Matared' cream could be a vehicle for transmitting Salmonella . Using the above combination of media, beside the suggested modified confirmatory procedure, should increase the effectiveness and ease of the detection of Salmonella in milk and dairy products. Lett Appl Microbiol, 2003, 37(5), 386 - 91 Evaluation of real-time PCR vs automated ELISA and a conventional culture method using a semi-solid medium for detection of Salmonella; Uyttendaele M et al.; AIMS: Evaluation of iQ-Check PCR Salmonella for Salmonella detection in artificially and naturally contaminated food and environmental field samples . METHODS AND RESULTS: Artificially contaminated samples (poultry meat and ground red meat) subjected to cold- and freeze-stress, and 120 naturally contaminated samples (swabs and meat) were tested for Salmonella using the diagnostic semi-solid Salmonella medium (DIASALM) method, the Vidas assay and the iQ-Check PCR assay after 24 h enrichment in buffered peptone water . CONCLUSIONS: Both the iQ-Check PCR and the Vidas assay provide a rapid and user friendly screening method for detection of Salmonella . False negative samples were obtained for the inoculated samples using both the iQ-Check PCR assay and the Vidas method when Salmonella cells were severely stressed . In total 45 of 120 naturally contaminated field samples showed Salmonella positive using the DIASALM method . The agreement percentage with the DIASALM method was respectively 92% for the iQ-Check PCR and 95% for the Vidas method . SIGNIFICANCE AND IMPACT OF THE STUDY: False-negative samples were obtained for the inoculated samples using both the iQ-Check PCR assay and the Vidas method when Salmonella cells were severely stressed, e.g . freezing at -18 degrees C for 7 days . Of the 120 naturally contaminated field samples 45 showed Salmonella positive using the DIASALM method . The agreement percentage with the DIASALM method was 92% for the iQ-Check PCR and 95% for the Vidas method respectively. Lett Appl Microbiol, 2003, 37(6), 482 - 7 Inactivation of Escherichia coli O157:H7, Salmonella enteritidis and Listeria monocytogenes on the surface of tomatoes by neutral electrolyzed water; Deza MA et al.; AIMS: To determine the efficacy of neutral electrolyzed water (NEW) in killing Escherichia coli O157:H7, Salmonella enteritidis and Listeria monocytogenes, as well as nonpathogenic E . coli, on the surface of tomatoes, and to evaluate the effect of rinsing with NEW on the organoleptic characteristics of the tomatoes . METHODS AND RESULTS: The bactericidal activity of NEW, containing 444 or 89 mg l(-1) of active chlorine, was evaluated over pure cultures (8.5 log CFU ml(-1)) of the above-mentioned strains . All of them were reduced by more than 6 log CFU ml(-1) within 5 min of exposure to NEW . Fresh tomatoes were surface-inoculated with the same strains, and rinsed in NEW (89 mg l(-1) of active chlorine) or in deionized sterile water (control), for 30 or 60 s . In the NEW treatments, independent of the strain and of the treatment time, an initial surface population of about 5 log CFU sq.cm(-1) was reduced to <1 log CFU sq.cm(-1), and no cells were detected in the washing solution by plating procedure . A sensory evaluation was conducted to ascertain possible alterations in organoleptic qualities, yielding no significant differences with regard to untreated tomatoes . SIGNIFICANCE AND IMPACT OF THE STUDY: Rinsing in NEW reveals as an effective method to control the presence of E . coli O157:H7, S . enteritidis and L . monocytogenes on the surface of fresh tomatoes, without affecting their organoleptic characteristics . This indicates its potential application for the decontamination of fresh produce surfaces. J Appl Microbiol, 2003, 95(5), 1134 - 42 DNA fingerprinting of human isolates of Salmonella enterica serotype Paratyphi B in Malaysia; Goh YL et al.; AIMS: DNA fingerprinting of Salmonella enterica serotype Paratyphi B isolated in Malaysia during 1982-83, 1992 and 1996-2002 was carried out by pulsed-field gel electrophoresis (PFGE), antimicrobial susceptibility tests and D-tartrate utilization tests to assess the extent of genetic diversity of these isolates in Malaysia . METHODS AND RESULTS: Eighty-six human isolates and one food isolate of Salm . Paratyphi B were analysed by PFGE, antimicrobial susceptibility tests and D-tartrate utilization tests . Sixty-five strains were D-tartrate-negative (dT-) while 22 strains were D-tartrate-positive (dT+) . Thirty-seven per cent of the Salm . Paratyphi B strains were resistant to one or more antimicrobial agents . PFGE analysis clearly distinguished the dT- and dT+ strains into two clusters based on the unweighted pair group average method (UPGMA) . Twenty-two XbaI-pulsotypes were observed among the 65 dT- strains while 17 XbaI-pulsotypes were observed among the 22 isolates of Salm . Paratyphi B dT+ . CONCLUSIONS: The present study showed that PFGE was very discriminative with 33.7% of the strains yielding distinct fingerprints . Paratyphoid fever in Malaysia is probably caused by one predominant, endemic clone of Salm . Paratyphi B dT- with various subtypes . There was no association between the pulsotypes and the severity of the disease indicating that the severity of the disease is probably multifactorial . SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of the present study verify the usefulness of PFGE in characterizing strains of Salm . Paratyphi B . This is the first report on the application of PFGE on a large collection of Salm . Paratyphi B in Malaysia. J Appl Microbiol, 2003, 95(5), 1016 - 25 Evaluation of the use of pooled serum, pooled muscle tissue fluid (meat juice) and pooled faeces for monitoring pig herds for Salmonella; Davies RH et al.; AIMS: Monitoring for Salmonella in slaughter pigs is important to enable targeted control measures to be applied on problem farms and at the abattoir . The aim of this study was to determine whether pooled serum and meat juice could be used to identify finishing pig herds with a high prevalence of infection . METHODS AND RESULTS: Samples of meat juice, serum, caecal contents, carcase swabs and pooled faeces from pig pens were taken from 20 commercial pig finishing farms and comparisons were made between the results of Salmonella culture, individual ELISA tests on serum and meat juice and pooled samples of serum and meat juice . Salmonella was isolated from samples from 19 of 20 farms . None of the ELISA tests showed a statistically significant correlation with caecal carriage of Salmonella or contamination of carcases . Serum mean optical density (O.D.) from pools of five, 10 or 20 sera showed a significant correlation with the Salmonella status of farm pen faeces . All pooled serum O.D . and sample/positive control ratio results correlated significantly with the results of the conventional individual sample ELISA . There was a statistically significant correlation between the incidence of Salmonella in farm pen pooled faeces and the prevalence of Salmonella in caeca of slaughter pigs . CONCLUSIONS: The results show a generally poor correlation between serological and bacteriological results but pooled serum or meat juice samples could be used as a cheaper substitute for serological screening of farms for Salmonella than individual samples . SIGNIFICANCE AND IMPACT OF THE STUDY: The availability of a cheaper test should allow the costs of Salmonella monitoring of pig farms to be reduced or allow more regular testing to enhance the designation of farm Salmonella risk status. J Appl Microbiol, 2003, 95(5), 891 - 903 Salmonella on pig carcasses: positive pigs and cross contamination in the slaughterhouse; Botteldoorn N et al.; AIMS: The purpose of this study was to investigate the prevalence of Salmonella in pigs at the moment of slaughter and in the slaughterhouse environment . METHODS AND RESULTS: In total, five different commercial slaughterhouses were sampled during eight slaughterhouse visits . Carcass swabs, colon content and mesenteric lymph nodes were taken to reflect the animal status and from the slaughterhouse environmental samples were taken . Salmonella was isolated from 37% of the carcass samples as a mean value . High variations were noticed between different slaughterhouses (between 0 and 70%) and sampling days in the same abattoir (between 3 and 52%) . A correlation was found between the carcass contamination and the status of the delivered animals (P=0.01675) . Cross contamination was estimated to account for 29% of the positive carcasses . The slaughterhouse environment was highly contaminated; before starting the slaughtering activities 25% of the samples were positive on average . The most prevalent serotypes isolated at the slaughterhouse environment and from the colon content were S . Typhimurium, S . Livingstone and S . Derby . On carcasses S . Typhimurium was predominately isolated (71%) . The biggest variability of serotypes was found in the mesenteric lymph nodes . Serologically 56.3% of the pigs were found positive for Salmonella using a cut-off level of the optical density percentage higher than 10 (O.D.% > or = 10) . While on individual pig level the correlation between the bacteriological and serological data was poor, because of recent Salmonella infections, a better correlation was found at the herd level on the moment of slaughtering . CONCLUSION: A high degree of carcass contamination is noticed after slaughtering . This contamination resulted from the delivery of Salmonella-positive pigs and cross-contamination from the slaughterhouse environment . SIGNIFICANCE AND IMPACT OF THE STUDY: In pigs, Salmonella carriage is high, but it is obvious that slaughterhouse hygiene is a determinative factor for managing carcass contamination. J Appl Microbiol, 2003, 95(6), 1351 - 60 The effects of cleaning and disinfection in reducing Salmonella contamination in a laboratory model kitchen; Barker J et al.; AIMS: To establish a laboratory model to compare the effectiveness of detergent-based disinfection procedures for reducing cross-contamination risks during handling of contaminated chicken . METHODS AND RESULTS: During handling of chickens, artificially contaminated with Salmonella enteritidis PT4, the organism was widely spread to hands, cloths, and hand- and food-contact surfaces . Hygiene procedures were assessed on the basis of their ability to reduce the number of recoverable salmonellas to <1 CFU . Although detergent-based cleaning using a typical bowl-wash routine without rinsing produced some risk reduction (from 100 to 61.4% of contaminated surfaces), it was insufficient to consistently restore surfaces to a hygienic state . By combining detergent-based cleaning with a rinsing step or with hypochlorite at 500 ppm (of available chlorine) some further reduction in microbial risk was achieved, but was not considered satisfactory for food hygiene purposes . By contrast the risk reduction produced by hypochlorite at 5000 ppm was highly significant and was sufficient to reduce the number of contaminated surfaces to 2.9% . CONCLUSIONS: A key step in achieving a hygienic state through detergent-based cleaning is rinsing but even this will not produce a 'hygienic' result for difficult surfaces such as the chopping board or the dishcloth . Disinfectant compounds should be considered in order to reduce the potential for foodborne cross infection within the home environment . SIGNIFICANCE AND IMPACT OF THE STUDY: Although tests are available to determine the performance of disinfectants, there are no quantitative procedures available to compare the risk reduction achieved by disinfection with that produced by detergent-based procedures . This study describes a reproducible laboratory method which can be used to differentiate the effectiveness of different hygiene procedures for reducing cross-contamination risks during food handling. J Appl Microbiol, 2003, 95(6), 1343 - 50 Nucleic acid sequence based amplification for the rapid and sensitive detection of Salmonella enterica from foods; D'Souza DH et al.; AIMS: The purpose of this study was to apply nucleic acid sequence-based amplification (NASBA) for the detection of Salmonella enterica serovar Enteritidis (S . Enteritidis) in representative foods . METHODS AND RESULTS: A previously reported primer and probe set based on mRNA sequences of the dnaK gene of Salmonella were used in this study . To test for possible food matrix inhibition and assay detection limits, 25-g samples of representative food commodities (fresh meats, poultry, fish, ready-to-eat salads and bakery products) were pre-enriched with and without S . Enteritidis inoculation . The NucliSens(R) Basic Kit, supplemented with enzymes from various other commercial sources, was used for RNA isolation, NASBA amplification and electrochemiluminescent (ECL) detection . The end point detection limit of the NASBA-ECL assay was equivalent to 101 CFU of S . Enteritidis per amplification reaction . When the assay was tested on noncontaminated foods, none of the food matrices produced false-positive results . Some of the food matrices inhibited the NASBA-ECL reaction unless the associated RNA was diluted 10-fold prior to amplification . CONCLUSIONS: For all food items tested, positive ECL signals were achieved after 18 h of pre-enrichment and subsequent NASBA at initial inoculum levels of 102 and 101 CFU per 25 g food sample . SIGNIFICANCE AND IMPACT OF THE STUDY: This rapid, semi-automated detection method has potential for use in the food, agricultural and public health sectors. Res Commun Mol Pathol Pharmacol, 2002, 111(1-4), 3 - 12 Human natural killer cell lysis of Salmonella typhi intracellularly-infected U937 cells; Miranda D et al.; Peripheral blood mononuclear cell (PBMC) cytotoxicity against S . typhi (wild type or mutant strain TYT1231)-infected U937 cells was significantly higher than its lytic effect against noninfected cells (control) at the various effector-to-target cell ratio used (30:1, 50:1 and 70:1) . Natural killer cell activity {expressed as % specific lysis (mean +/- SEM); 30:1 (25.4 +/- 3.6, 25.1 +/- 4.2 and 16.3 +/- 3.3); 50:1 (27.8 +/- 3.7, 26.7 +/- 4.5 and 20.9 +/- 2.9) and 70:1 ratio (33.2 +/- 5.9, 29.4 +/- 4.2 and 22.8 +/- 2.8), respectively} appeared to be dependent on such ratios and independent of the S strain studied . Most (80%) of individual samples tested showed at least a 20% specific lysis increase over their own control; essentially no changes or smaller increases in NKC activity were observed in all other samples . Similar results were obtained when using highly purified NKC (HPNKC) preparations as effector cells {NKC activity (mean +/- SEM); 5:1 (46.2 +/- 4.7, 43.2 +/- 5.0 and 25.2 +/- 2.3) and 10:1 effector-to-target cell ratio (49.3 +/- 4.9, 44.7 +/- 5.2 and 27.2 +/- 2.6, respectively)} . All individual samples tested showed at least a 20% specific lysis increase over their own control . These results show that S . typhi-infected U937 cells are a significantly better target for NKCs than control cells and indicate that intracellular bacteria survival capacity is not a critical factor for infected cells becoming a NKC target. Toxicol In Vitro, 2004 Feb, 18(1), 29 - 35 Investigation of the antimutagenic effects of selected South African medicinal plant extracts; Verschaeve L et al.; Dichloromethane extracts from different parts of Rhamnus prinoides, Ornithogalum longibracteatum, Gardenia volkensii, Spirostachys africana, Diospyros whyteana, Syzigium cordatum and Prunus africana were investigated for mutagenic and antimutagenic effects in Salmonella/microsome and micronucleus tests . None of the extracts tested in the Ames test were found to induce mutations or to modify the effect of the mutagen 4-nitroquinoline-oxide (4NQO) . In the micronucleus test, extracts from twigs/bark of R . prinoides, twigs of D . whyteana, P . africana and S . cordatum significantly lowered the effect of the mutagen mitomycin C (MMC) . Extracts from twigs/bark of G . volkensii and S . africana were genotoxic in the micronucleus test, while extracts of O . longibracteatum leaves potentiated the genotoxicity of MMC . This preliminary investigation shows that plant extracts used in traditional medicine may have particular effects with regard to mutagenicity and antimutagenicity indicating careful use in some instances and the need to isolate their active principles for further research. Scand J Immunol, 2003 Nov, 58(5), 493 - 502 Nitric oxide produced by murine dendritic cells is cytotoxic for intracellular Salmonella enterica sv . Typhimurium; Eriksson S et al.; The pathogenicity of Salmonella enterica serovar Typhimurium has traditionally been correlated with its ability to survive and grow in macrophages . Macrophage-derived production of nitric oxide (NO) has been implicated as a major innate defence, restricting bacterial proliferation both in macrophage cultures and in mice . In the present study, we show that the ability of primary murine dendritic cells (DCs) to ingest Salmonella is low, but greatly enhanced by serum complement . Ingestion of bacteria was followed by the expression of inducible nitric oxide synthase (iNOS), as well as by NO production . iNOS mRNA was detected as early as 6 h post infection and production of NO 12 h post infection, rising further at 16 h post infection . Inhibition of the iNOS activity with the inhibitor N-monomethyl-l-arginine or using DCs from iNOS-/- mice resulted in increased intracellular bacterial yields . To further define the potential defensive role of DC-derived NO, the actual intracellular replication rate of S . Typhimurium in DCs was measured . DC-derived NO was shown to exert a bactericidal effect, whereas the effect of NO in macrophage-like J774-A.1 cells was found to be bacteriostatic . These results identified an important role for NO in restricting S . Typhimurium survival in DCs, indicating that DCs may actively participate in the innate defence against intracellular pathogens. J Food Prot, 2003 Nov, 66(11), 2160 - 3 In vivo assessment of effect of fermented milk diet on course of infection in mice with bioluminescent Salmonella; Brovko LY et al.; A novel method for assessing the effect of fermented milk and its components on the course of Salmonella infection in live mice is described . Following a period of feeding with whole fermented milk (group W), a cell-free fraction of fermented milk (group S), or saline (group C, control), mice were challenged by oral gavage with a bioluminescent strain of Salmonella Enteritidis . Colonization of the gastrointestinal tract and subsequent infection could be followed by bioluminescent imaging of live mice with a cooled slow-scan CCD camera . Each group of mice was fed for 7 days with the appropriate product . On the eighth day, all mice were orally infected with 10(6) Salmonella cells . On the sixth day after infection, mice in groups W and C showed evidence of disease . No bioluminescent signal was observed for any of the mice in group S . The physical condition of the mice in groups W and S was normal, but some deterioration in the health of the mice in the control group (group C) occurred . On the eighth day after infection, a weak bioluminescence signal was observed for the mice in group W, but still no signal was observed for any of the mice in group S . Mice in both of these groups appeared normal, but the mice in group C showed strong evidence of infection and marked deterioration in their physical condition accompanied by a bioluminescence signal . This method allows the assessment of the effects of potential nutraceutical agents on the course of infection by foodborne pathogens in live animals in real time. J Food Prot, 2003 Nov, 66(11), 2156 - 9 Microbial and sensory quality of marinated and irradiated chicken; Mahrour A et al.; Chicken legs were subjected to two pretreatments (packaged in air or marinated in natural plant extracts and then packaged in air) followed by irradiation (0, 3, or 5 kGy) . The control and irradiated chicken legs were stored at 4 degrees C and underwent microbial analysis (mesophilic aerobic plate counts and Salmonella detection) and sensory evaluation at predetermined intervals . Microbial analysis indicated that irradiation had a significant effect (P < or = 0.05) on the mesophilic aerobic plate counts of the poultry . For each treatment, the bacterial growth decreased with an increase of irradiation dose . The marinade had an additive effect with irradiation in reducing bacterial growth and controlling proliferation during storage at 4 +/- 1 degree C . No Salmonella was observed until day 12 in marinated chicken irradiated at 3 kGy and for all experiments with chicken legs stored under air or marinated at 5 kGy . However, Salmonella was found in chicken legs irradiated at 3 kGy in air and in nonirradiated samples . The sensory evaluation indicated a significant (P < or = 0.05) difference in odor and flavor intensities between the irradiated chicken at 5 kGy and the control . No significant difference was found (P > 0.05) between the marinated chicken irradiated at 5 kGy and the control. J Food Prot, 2003 Nov, 66(11), 2141 - 5 Real-time multiplex SYBR green I-based PCR assay for simultaneous detection of Salmonella serovars and Listeria monocytogenes; Jothikumar N et al.; A multiplex SYBR Green I-based PCR assay has been developed for simultaneous detection of Salmonella serovars and Listeria monocytogenes using a LightCycler . Primers were designed to amplify an 85-bp sequence from the gene encoding a fimbrinlike protein (fimI) of Salmonella Enteritidis and a 98-bp sequence from the hemolysin gene (hly) of L . monocytogenes . These primers allowed the amplification of PCR products having distinct melting temperature values, resulting in the formation of two distinct peaks representing the two targets . Background signals, resulting from primer-dimer formation in the late cycles of PCR, are eliminated through the acquisition of data at a high temperature (>75 degrees C), but several degrees lower than required for detection of the specific PCR products . A rapid and simple method for the extraction of bacterial genomic DNA from liquid culture, coupled with duplex PCR using LightCycler SYBR Green-based PCR assays, detected the presence of 2.5 cells and 1 cell of Salmonella serovars and L . monocytogenes, respectively, within an hour . Following overnight enrichment, target DNA was present in sufficient quantities in 1 microl of culture to enable direct detection with the LightCycler. J Food Prot, 2003 Nov, 66(11), 2123 - 9 Genotoxicity assessment of five tremorgenic mycotoxins (fumitremorgen B, paxilline, penitrem A, verruculogen, and verrucosidin) produced by molds isolated from fermented meats; Sabater-Vilar M et al.; A number of toxinogenic fungal species, particularly producers of tremorgenic mycotoxins, have been isolated from traditional fermented meats . Tremorgenic mycotoxins are a group of fungal metabolites known to act on the central nervous system, causing sustained tremors, convulsions, and death in animals . However, the mode of action of these mycotoxins has not been elucidated in detail, and their genotoxic capacity has hardly been investigated . Because genotoxicity is one of the most prominent toxicological end points in food safety testing, we assessed the genotoxicity of five tremorgenic mycotoxins (fumitremorgen B, paxilline, penitrem A, verrucosidin, and verruculogen) associated with molds found in fermented meats . The mycotoxins were tested in two short-term in vitro assays with the use of different genotoxic end points in different phylogenetic systems (the Ames Salmonella/mammalian-microsome assay and the single-cell gel electrophoresis assay of human lymphocytes) . According to the results obtained in this study, all of the investigated mycotoxins except penitrem A exhibited a certain degree of genotoxicity . Verrucosidin appeared to have the highest toxic potential, testing positive in both assays . Verruculogen tested positive in the Salmonella/mammalian-microsome assay, and paxilline and fumitremorgen B caused DNA damage in human lymphocytes . The use of fungal starter cultures to avoid tremorgen contamination in fermented meats is recommended. J Food Prot, 2003 Nov, 66(11), 2017 - 22 Reduction of Salmonella enterica on alfalfa seeds with acidic electrolyzed oxidizing water and enhanced uptake of acidic electrolyzed oxidizing water into seeds by gas exchange; Stan SD et al.; Alfalfa sprouts have been implicated in several salmonellosis outbreaks in recent years . The disinfectant effects of acidic electrolyzed oxidizing (EO) water against Salmonella enterica both in an aqueous system and on artificially contaminated alfalfa seeds were determined . The optimum ratio of seeds to EO water was determined in order to maximize the antimicrobial effect of EO water . Seeds were combined with EO water at ratios (wt/vol) of 1:4, 1:10, 1:20, 1:40, and 1:100, and the characteristics of EO water (pH, oxidation reduction potential {ORP}, and free chlorine concentration) were determined . When the ratio of seeds to EO water was increased from 1:4 to 1:100, the pH decreased from 3.82 to 2.63, while the ORP increased from +455 to +1,073 mV . EO water (with a pH of 2.54 to 2.38 and an ORP of +1,083 to +1,092 mV) exhibited strong potential for the inactivation of S . enterica in an aqueous system (producing a reduction of at least 6.6 log CFU/ml) . Treatment of artificially contaminated alfalfa seeds with EO water at a seed-to-EO water ratio of 1:100 for 15 and 60 min significantly reduced Salmonella populations by 2.04 and 1.96 log CFU/g, respectively (P < 0.05), while a Butterfield's buffer wash decreased Salmonella populations by 0.18 and 0.23 log CFU/g, respectively . After treatment, EO water was Salmonella negative by enrichment with or without neutralization . Germination of seeds was not significantly affected (P > 0.05) by treatment for up to 60 min in electrolyzed water . The uptake of liquid into the seeds was influenced by the internal gas composition (air, N2, or O2) of seeds before the liquid was added. J Food Prot, 2003 Nov, 66(11), 2010 - 6 Influence of inoculation method, spot inoculation site, and inoculation size on the efficacy of acidic electrolyzed water against pathogens on lettuce; Koseki S et al.; The influence of bacterial inoculation methods on the efficacy of sanitizers against pathogens was examined . Dip and spot inoculation methods were employed in this study to evaluate the effectiveness of acidic electrolyzed water (AcEW) and chlorinated water (200 ppm free available chlorine) against Escherichia coli O157:H7 and Salmonella spp . Ten pieces of lettuce leaf (5 by 5 cm) were inoculated by each method then immersed in 1.5 liters of AcEW, chlorinated water, or sterile distilled water for 1 min with agitation (150 rpm) at room temperature . The outer (abaxial) and inner (adaxial) surfaces of the lettuce leaf were distinguished in the spot inoculation . Initial inoculated pathogen population was in the range 7.3 to 7.8 log CFU/g . Treatment with AcEW and chlorinated water resulted in a 1 log CFU/g or less reduction of E . coli O157:H7 and Salmonella populations inoculated with the dip method . Spot inoculation of the inner surface of the lettuce leaf with AcEW and chlorinated water reduced the number of E . coli O157:H7 and Salmonella by approximately 2.7 and 2.5 log CFU/g, respectively . Spot inoculation of the outer surface of the lettuce leaf with both sanitizers resulted in approximately 4.6 and 4.4 log CFU/g reductions of E . coli O157:H7 and Salmonella, respectively . The influence of inoculation population size was also examined . Each sanitizer could not completely eliminate the pathogens when E . coli O157:H7 and Salmonella cells inoculated on the lettuce were of low population size (10(3) to 10(4) CFU/g), regardless of the inoculation technique. J Food Prot, 2003 Nov, 66(11), 1987 - 95 Evaluation of methods for recovery of Salmonella from dairy cattle, poultry, and swine farms; Pangloli P et al.; Current official methods for detection and isolation of Salmonella are mostly designed for foods . The objective of this study was to determine optimal methods for detection and isolation of Salmonella from animal and environmental samples of dairy, poultry, and swine farms . Preenrichment in lactose broth versus direct enrichment (no preenrichment) prior to selective enrichment in Rappaport-Vassiliadis, selenite cystine, and tetrathionate incubated at 35 and 42 degrees C and in four differential/selective plating media (brilliant green, bismuth sulfite, Hektoen enteric, and xylose-lysine-tergitol 4 agar base) were evaluated for their ability to recover Salmonella from artificially contaminated samples . The effects of pH adjustments to samples on Salmonella recovery were determined . A pH adjustment of the enrichment broth to 6.8 +/- 0.2 after addition of samples significantly improved recovery of Salmonella . The most effective medium combinations for isolation of Salmonella from farm samples depended on the type of samples . Generalizations of protocols for recovery of Salmonella from farm samples might result in poor recovery, increased recovery time, and increased sample processing costs. J Food Prot, 2003 Nov, 66(11), 1964 - 71 Attraction of a free-living nematode, Caenorhabditis elegans, to foodborne pathogenic bacteria and its potential as a vector of Salmonella poona for preharvest contamination of cantaloupe; Caldwell KN et al.; Caenorhabditis elegans was studied to determine the potential role of free-living microbivorous nematodes as vectors for preharvest contamination of fruits and vegetables with foodborne pathogens . The propensity of C . elegans to be attracted to seven strains of Escherichia coli O157:H7, eight serotypes of Salmonella, six strains of Listeria monocytogenes, and cantaloupe juice was investigated . Twenty to 30 adult worms were placed on the surface of K agar midway between a 24-h bacterial colony and 10 microl of uninoculated tryptic soy broth (TSB) or cantaloupe juice positioned 1.5 cm apart . The numbers of nematodes that migrated to the colony, to the TSB, and to the cantaloupe juice within 5, 10, 15, and 20 min at 21 degrees C were determined, and then the plates were incubated at 37 degrees C for up to 7 days to determine the ability of C . elegans to survive and reproduce in bacterial colonies . The nematode was attracted to colonies of all test pathogens and survived and reproduced within colonies for up to 7 days . C . elegans was not attracted to cantaloupe juice . The potential of C . elegans to serve as a vector for the transport of Salmonella Poona to cantaloupe rinds was investigated . Adult worms that had been immersed in a suspension of Salmonella Poona were deposited 1 or 3 cm below the surface of soil on which a piece of cantaloupe rind was placed . The rind was analyzed for the presence of Salmonella Poona after 1, 3, 7, and 10 days at 21 degrees C . The presence of Salmonella Poona was evident more quickly on rinds positioned on soil beneath which C . elegans inoculated with Salmonella Poona was initially deposited than on rinds positioned on soil beneath which Salmonella Poona alone was deposited . The time required to detect Salmonella Poona on rinds was longer when the rind was placed 3 cm above the inoculum than when the rind was placed 1 cm above the inoculum . Free-living nematodes may play a role in the preharvest dispersal of incidental human pathogens in soil to the surfaces of raw fruits and vegetables in contact with soil during development and maturation, as evidenced by the behavior of C . elegans as a test model. Cell Stress Chaperones, 2003 Summer, 8(2), 194 - 203 Expression levels of heat shock proteins in enterocyte-like Caco-2 cells after exposure to Salmonella enteritidis; Malago JJ et al.; The enterocytes of the small intestine are occasionally exposed to pathogenic bacteria, such as Salmonella enteritidis 857, an etiologic agent of intestinal infections in humans . The expression of the heat shock response by enterocytes may be part of a protective mechanism developed against pathogenic bacteria in the intestinal lumen . We aimed at investigating whether S . enteritidis 857 is able to induce a heat shock response in crypt- and villus-like Caco-2 cells and at establishing the extent of the induction . To establish whether S . enteritidis 857 interfered with the integrity of the cell monolayer, the transepithelial electrical resistance (TEER) of filter-grown, differentiated (villus-like) Caco-2 cells was measured . We clearly observed damage to the integrity of the cell monolayer by measuring the TEER . The stress response was screened in both crypt- and villus-like Caco-2 cells exposed to heat (40-43 degrees C) or to graded numbers (10(1)-10(8)) of bacteria and in villus-like cells exposed to S . enteritidis 857 endotoxin . Expression of the heat shock proteins Hsp70 and Hsp90 was analyzed by polyacrylamide gel electrophoresis and immunoblotting with monoclonal antibodies . Exposure to heat or Salmonella resulted in increased levels of Hsp70 and Hsp90 in a temperature-effect or Salmonella-dose relationship, respectively . Incubation of Caco-2 cells with S . enteritidis 857 endotoxin did not induce heat shock gene expression . We conclude that S . enteritidis 857 significantly increases the levels of stress proteins in enterocyte-like Caco-2 cells . However, our data on TEER clearly indicate that this increase is insufficient to protect the cells. Int J Hyg Environ Health, 2003 Oct, 206(6), 539 - 51 Exposures to drinking water chlorination by-products in a Russian city; Egorov AI et al.; Exposures to water disinfection by-products (DBPs) via ingestion of drinking water, and dermal absorption and inhalation during showering/bathing were assessed in the city of Cherepovets, Russia, which uses heavy chlorination to disinfect organic-rich surface water . Concentrations of DBPs (mean +/- standard deviation) in tap water were the following: total trihalomethanes (THMs) 205 +/- 70 micrograms/l, five haloacetic acids (HAAs) 150 +/- 30 micrograms/l, and 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (mutagen X or MX) 160 +/- 50 ng/l . Concentrations of THMs and HAAs exceeded the corresponding US standards by a factor of 2.5, while MX concentrations were the highest ever reported . The mutagenic activity of tap water extracts in the Salmonella TA-100 assay was 14,900 net revertants/l . Concentrations of chloroform in breathing zone air in bathrooms during showering were 330 +/- 260 micrograms/m3, shower room air at an industrial plant 2,600 +/- 1,100 micrograms/m3, and bedrooms of local residents 2 +/- 2 micrograms/m3 . The mean concentration of chloroform was 3.2 micrograms/m3 in exhaled air samples collected before showering and 110 micrograms/m3 after showering . Data on water ingestion and water use practices in the general population and for pregnant women were collected using questionnaires and diaries . Due to concerns over microbiological safety of water, average daily consumption of non-boiled tap water in pregnant women was only 0.01 l/day, while consumption of boiled tap water was 0.81 l/day . This resulted in low ingestion exposures to volatile THMs . Inhalation and dermal absorption determined total exposures to these compounds . HAAs and MX persist in boiled water and drinks resulting in high ingestion exposures . Several brands of inexpensive home water filters were tested for removal of these compounds . To demonstrate a method of exposure reduction in a sensitive subpopulation, the most efficient filters were given to a group of pregnant women . These women and a control group of pregnant women without filters maintained water ingestion diaries for two weeks . The use of home filters resulted in reduction of exposures to HAAs by a factor of three and a greater reduction in exposures to MX. Int J Food Microbiol, 2003 Dec 31, 89(2-3), 241 - 9 Interlaboratory diagnostic accuracy of a Salmonella specific PCR-based method; Malorny B et al.; A collaborative study involving four European laboratories was conducted to investigate the diagnostic accuracy of a Salmonella specific PCR-based method, which was evaluated within the European FOOD-PCR project . Each laboratory analysed by the PCR a set of independent obtained presumably naturally contaminated samples and compared the results with the microbiological culture method . The PCR-based method comprised a preenrichment step in buffered peptone water followed by a thermal cell lysis using a closed tube resin-based method . Artificially contaminated minced beef and whole broiler carcass-rinse resulted in a detection limit of less than 5 cells per 25 g meat or 100 ml broiler rinse . A total of 435 samples from four countries, including pig carcass swabs (n = 285), whole broiler carcass-rinse (n = 25), various raw meat (n = 33), and environmental samples (n = 92) were investigated . The interlaboratory diagnostic accuracy, i.e . diagnostic specificity and sensitivity, was shown to be 97.5% . The co-amplification of an internal amplification control indicated possible inhibitory substances derived from the sample . This work can contribute to the quality assurance of PCR-based diagnostic methods and is currently proposed as international standard document. Bone, 2003 Nov, 33(5), 812 - 21 Bacterial infection induces expression of functional MHC class II molecules in murine and human osteoblasts; Schrum LW et al.; A growing body of evidence has shown that bacterially challenged osteoblasts can play a significant role in the initiation of inflammatory immune responses at sites of bone disease . We have recently demonstrated the surprising ability of osteoblasts exposed to bacteria to express CD40, a molecule that plays a critical costimulatory role in the activation of T lymphocytes . In the present study, we have extended our investigations into the ability of osteoblasts to interact with CD4+ T lymphocytes by determining the expression of antigen-presenting major histocompatibility complex (MHC) class II molecules in murine and human osteoblasts following exposure to two common pathogens of bone, Staphylococcus aureus and Salmonella . Cultured osteoblasts were found to respond rapidly to bacterial challenge by induction of mRNA encoding MHC class II molecules or its transcriptional regulator . Increased mRNA expression translated into expression of MHC class II proteins in murine and human osteoblasts as determined by Western blot analysis and by immunohistochemical and immunofluorescent microscopy . Furthermore, the increased surface expression of these molecules on osteoblasts exposed to bacteria was confirmed by FACS analysis . Finally, we show that bacterial challenge results in the elevated functional expression of MHC class II molecules on osteoblasts by demonstrating the enhanced ability of these cells to interact with T lymphocytes and to initiate antigen-specific T cell activation . Taken together, these data suggest a previously unappreciated role for osteoblasts in the initiation of T lymphocyte activation at sites of bacterial infection in bone tissue. Vet Rec, 2003 Oct 25, 153(17), 517 - 20 Epidemiology of Salmonella enterica serovars enteritidis and Typhimurium in animals and people in Scotland between 1990 and 2001; Smith-Palmer A et al.; Two serovars of salmonella which are currently of particular importance in both human and animal infections are Salmonella enterica serovars Enteritidis phage type 4 (PT4) and Typhimurium definitive type 104 (DT104) . This paper describes the trends in the relationships between the levels of infection of people and a range of farm animal species with these two serovars and explores some of the reasons behind them . In 1996, there was a peak of 520 reports of S Typhimurium DT104 infection in people in Scotland, but the number has decreased every year since, to 96 in 2001 . In cattle the incidence of S Typhimurium DT104 also peaked in 1996, with 138 incidents, and it has similarly decreased every year to 2001 when there were 10 reported incidents . Similar declines have been observed in its incidence in sheep and pigs . In people the number of reports of S Enteritidis PT4 peaked in 1997 at 1684 and then declined to 457 in 2001 . In chickens, the number of reports of S Enteritidis PT4 peaked in 1998 at 34 incidents, but no incidents were reported in the following three years. Am J Orthop, 2003 Oct, 32(10), 505 - 9 Treatment of multifocal vancomycin-resistant Enterococcus faecium osteomyelitis in sickle cell disease: a preliminary report; Bibbo C et al.; Repeat episodes of musculoskeletal infarction coupled with immunosuppression predispose sickle cell patients to infectious complications throughout their lives . Osteomyelitis is a familiar complication of sickle cell disease, and it may result in significant morbidity, especially when occurring in multiple sites . Staphylococcus and Salmonella remain the most common causes of osteomyelitis in sickle cell patients . Vancomycin-resistant enterococcus (VRE) infections have been reported mainly in connection with bacteremias and infections outside of the musculoskeletal system . To our knowledge, only a few cases of VRE long bone osteomyelitis have been reported in the literature . A few antimicrobial agents are available to treat VRE infections . The occurrence of VRE osteomyelitis is a major clinical concern, especially in an immunocompromised host, such as a sickle cell patient . We present a case of multiple long bone vancomycin-resistant Enterococcus faecium (mixed organisms) osteomyelitis in a sickle cell patient, and we report on a new method of using quinupristin-dalfopristin as part of the management plan to treat a complicated VRE infection successfully . We discuss the mechanism of action of anti-VRE drugs and the future direction to combat VRE in orthopedic infections. Mol Cell Biochem, 2003 Nov, 253(1-2), 15 - 9 Modulation of gut physiology through enteric toxins; Kaur T et al.; Diarrheal diseases caused by microorganisms and their toxins are a major cause of mortality and morbidity throughout the world . Acute diarrhea is mainly caused due to increased intestinal secretion, commonly as a result of infection with enterotoxin producing organisms (enterotoxigenic Escherichia coli, Vibrio cholera) or due to decreased intestinal absorption from infection with organisms that damage the intestinal epithelium (enteropathogenic E . coli sp., Shigella sp., Salmonella sp.) The studies of the impact of enteric pathogens and their virulence factors exert their effect by producing toxins, called bacterial toxins . The protein toxins are produced by diverse group of bacteria . Most of the bacterial toxins exert their effect through involvement of ADP-ribosylation proteins; otherwise essential for several cellular functions while other toxins involve guanylate cyclase systems or calcium and protein kinases for their ultimate action. Medicina (Kaunas), 2003, 39 Suppl 2, 70 - 5 {Antimicrobial action of ammonium salts of fused heterocycles containing ortho-nitrogen}; Stankeviciene L et al.; By alkylation of hexamethylenetetramine with halogenated derivatives of ketones, ethers, esters or amides of acids, alkyl- and aralkyl halides the corresponding N-monoalkylated compounds of hexamethylenetetramine were obtained . The quaternization of pyridine nitrogen in 5,6-benzoquinoline, 8-hydroxyquinoline, quinoline, 1,10-phenanthroline molecules with alkyl- or aralkylhalides was carried out . The susceptibility of Gram-positive (Streptococcus agalactiae and Staphylococcus aureus) and Gram-negative (E . coli, Salmonella cholerae suis, Salmonella enteridis Gartneri) microorganisms to synthesized quaternary ammonium salts by disc difussion method has been detected . The bacteriostatic action of 0.5-1% solutions of all compounds was assessed in comparison with benzalkonium chloride . It was shown, that the most effectiveness against all strains is possessed by quaternary hexamethylenetetramine ammonium salts, and especially salts, containing 1-propynyl- or hydroxycarbamoylmethyl radicals . The action of these two compounds against Salmonella and Streptococcus was stronger than the action of benzalkonium chloride . Susceptibility of Pseudomonas aeruginosa to these compounds were detected . It was shown, that 1% solutions of chlorides of N-(1-propynyl) hexamethylenetetramonium and N-(hydroxycarbamoylmethyl) hexamethylenetetrammonium demonstrate the same bacteriostatic action against P . aeruginosa as well as benzalkonium chloride. J Bacteriol, 2003 Dec, 185(23), 6950 - 67 Role of the Salmonella pathogenicity island 1 (SPI-1) protein InvB in type III secretion of SopE and SopE2, two Salmonella effector proteins encoded outside of SPI-1; Ehrbar K et al.; Salmonella enterica subspecies 1 serovar Typhimurium encodes a type III secretion system (TTSS) within Salmonella pathogenicity island 1 (SPI-1) . This TTSS injects effector proteins into host cells to trigger invasion and inflammatory responses . Effector proteins are recognized by the TTSS via signals encoded in their N termini . Specific chaperones can be involved in this process . The chaperones InvB, SicA, and SicP are encoded in SPI-1 and are required for transport of SPI-1-encoded effectors . Several key effector proteins, like SopE and SopE2, are located outside of SPI-1 but are secreted in an SPI-1-dependent manner . It has not been clear how these effector proteins are recognized by the SPI-1 TTSS . Using pull-down and coimmunoprecipitation assays, we found that SopE is copurified with InvB, the known chaperone for the SPI-1-encoded effector protein Sip/SspA . We also found that InvB is required for secretion and translocation of SopE and SopE2 and for stabilization of SopE2 in the bacterial cytosol . Our data demonstrate that effector proteins encoded within and outside of SPI-1 use the same chaperone for secretion via the SPI-1 TTSS. J Bacteriol, 2003 Dec, 185(23), 6921 - 7 Products transcribed from rearranged rrn genes of Escherichia coli can assemble to form functional ribosomes; Zaporojets D et al.; To examine the flexibility of rRNA operons with respect to fundamental organization, transcription, processing, and assembly of ribosomes, operon variations were introduced by a plasmid into an Escherichia coli strain that has deletions of all chromosomal copies of rRNA genes . In the reconstructed operons, a Salmonella intervening sequence (IVS) from 23S helix 45 was introduced into the E . coli 23S gene at the same position . Three different constructs of the E . coli 16S gene were then placed wholly within the IVS sequence, and the 16S gene was deleted from its normal position . The resulting plasmids thus had the normal operon promoters and the leader region followed by the 5' one-third of the 23S gene, the entire 16S gene within the IVS, the last two-thirds of the 23S gene, and the normal end of the operon . The three constructs differed in the amount of 16S leader and spacer regions they contained . Only two of the three constructs, those with redundant leader and spacer antiterminator signals, resulted in viable cultures of the rrn deletion strain . Electron micrographs of the variant operon suggest that the 23S rRNA is made in two separate parts which then must form subassemblies before assembling into a functional 50S subunit . Cells containing only the reshuffled genes were debilitated in their growth properties and ribosome contents . The fact that such out of the ordinary manipulation of rRNA sequences in E . coli is possible paves the way for detailed analysis of ribosome assembly and evolution. Clin Microbiol Infect, 2003 Aug, 9(8), 866 - 8 Salmonella sepsis and miscarriage; Coughlin LB et al.; We present a case of a miscarriage at 16 weeks of gestation due to infection and transplacental passage of Salmonella group C . This was identified as being Salmonella Virchow from genital tract swab culture, and placental Gram-staining revealed numerous colonies of Gram-negative bacilli within the fibrin between the placental villi, confirming a true villitis associated with a hematogenous infection . Based on the patient's history, it was suggested that she had contracted the salmonella infection from eating undercooked eggs . Treatment of salmonella infection in pregnancy is controversial, and antibiotic therapy should be reserved for cases of invasive disease, using amoxicillin or a cephalosporin. Clin Microbiol Infect, 2003 Aug, 9(8), 839 - 45 A European outbreak of Salmonella enterica serotype Typhimurium definitive phage type 204b in 2000; Crook PD et al.; OBJECTIVE: To describe the clinical, epidemiologic and microbiological features of a large outbreak of infection with a multiresistant Salmonella enterica serotype Typhimurium definitive type DT204b infection involving at least 392 people in five European countries . METHODS: Icelandic public-health doctors responded to a report on an Internet news site of an outbreak of infection with a multiresistant strain of Typhimurium DT104 in England by contacting the Public Health Laboratory Service (PHLS) Communicable Disease Surveillance Centre (CDSC) . An international alert was sent out through Enter-net . All strains from England & Wales, The Netherlands, Scotland and Germany, and 17 of the outbreak isolates from Iceland, were phage-typed, screened for antimicrobial resistance, and subjected to molecular typing . Hypothesis-generating interviews were conducted, followed by case-control studies performed in Iceland and England . RESULTS: Isolates from cases in Iceland, England and Wales, The Netherlands, Scotland and Germany were identified as Typhimurium DT204b . The antimicrobial resistance pattern was ACGNeKSSuTTmNxCpL . All strains tested displayed an identical plasmid profile . Strains from five cases in England & Wales and five cases in Iceland possessed identical pulsed-field profiles . Although a common source was suspected, only Iceland implicated imported lettuce as a vehicle, with an analytic epidemiologic study (OR = 40.8; P = 0.005; 95% CI 2.7-3175) . CONCLUSION: The identification of international outbreaks, necessary for investigation and control, can be facilitated by standardized phage-typing techniques, the electronic transfer of molecular typing patterns, formal and informal links established through international surveillance networks, and the early reporting of national outbreaks to such networks. Med Microbiol Immunol (Berl), 2003 Nov, 192(4), 205 - 9 Epub 2003 Jan 09. Human T lymphotropic virus type 1 in a seronegative B chronic lymphocytic leukemia patient; Stark P et al.; Human T lymphotropic virus type 1 (HTLV-1) is the etiological agent of adult T cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis . HTLV-1 infection in patients with B cell-type chronic lymphocytic leukemia (B-CLL) is rare and has been reported only in areas in which HTLV-1 is endemic . In the present study, we detected HTLV-1 proviral DNA by polymerase chain reaction, using tax primers, in peripheral blood lymphocytes from a B-CLL patient, an immigrant to Israel, where HTLV-1 infection is not endemic . F344 rats injected intravenously with peripheral blood lymphocytes obtained from the patient developed HTLV-1 antibodies . Titers of antibody to HTLV-1 in the rat blood were 1:512 by particle agglutination; enzyme-linked immunosorbent assay and Western blotting were also positive . No antibody against HTLV-1 was demonstrated in the animal model after inoculation of either purified B lymphocytes from the B-CLL patient or peripheral blood mononuclear cells from healthy donors . This is one of the few studies showing the presence of HTLV-1 provirus in T lymphocytes of a B-CLL patient who had multiple infections, and died of salmonella sepsis, and the first report of HTLV-1 antibody induction in an animal model by inoculation of lymphocytes obtained from an HTLV-1-infected B-CLL patient. Biol Proced Online, 2003, 5, 189 - 196 Epub 2003 Sep 26. Swarming populations of Salmonella represent a unique physiological state coupled to multiple mechanisms of antibiotic resistance; Kim W et al.; Salmonella enterica serovar Typhimurium is capable of swarming over semi-solid surfaces . Although its swarming behavior shares many readily observable similarities with other swarming bacteria, the phenomenon remains somewhat of an enigma in this bacterium since some attributes skew away from the better characterized systems . Swarming is quite distinct from the classic swimming motility, as there is a prerequisite for cells to first undergo a morphological transformation into swarmer cells . In some organisms, swarming is controlled by quorum sensing, and in others, swarming has been shown to be coupled to increased expression of important virulence factors . Swarming in serovar Typhimurium is coupled to elevated resistance to a wide variety of structurally and functionally distinct classes of antimicrobial compounds . As serovar Typhimurium differentiates into swarm cells, the pmrHFIJKLM operon is up-regulated, resulting in a more positively charged LPS core . Furthermore, as swarm cells begin to de-differentiate, the pmr operon expression is down-regulated, rapidly reaching the levels observed in swim cells . This is one potential mechanism which confers swarm cells increased resistance to antibiotics such as the cationic antimicrobial peptides . However, additional mechanisms are likely associated with the cells in the swarm state that confer elevated resistance to such a broad spectrum of antimicrobial agents. J Pediatr Surg, 2003 Nov, 38(11), 1693 - 5 A case of retroperitoneal abscess caused by Salmonella Oranienburg; Katsuno S et al.; The authors report a case of retroperitoneal abscess caused by Salmonella Oranienburg in an 8-year-old girl . This was one case in an epidemic of food poisoning from Salmonella Oranienburg or Salmonella Chester transmitted by many kinds of contaminated dried squid products . This is the first reported case of a retroperitoneal abscess by Salmonella Oranienburg. J Vet Sci, 2001 Apr, 2(1), 33 - 6 Competitive exclusion against Salmonella gallinarum of Salmonella enteritidis infected chickens; Lee YJ et al.; To evaluate the degree of competitive exclusion against Salmonella gallinarum(S . gallinarum) of Salmonella enteritidis(S . enteritidis) infected chickens, fifty-six, 4-week old Hyline layer suspected of S . enteritidis infection were challenged with S . gallinarum . All chickens were tested for S . enteritidis isolation using cloacal swabs and serum plate agglutination test using S . enteritidis Ag . before challenge and classified into four groups(SE isolated, SE nonisolated, SE seropositive and SE seronegative) . None of the SE isolated and the SE seropositive groups died after challenge and the average weight gains were 245.5g and 254.6g, respectively . But in the SE nonisolated and the SE seronegative groups, mortality was 18.2% and 20.6% and the average weight gains were 150.1g and 111.2g . The incidence of reisolation of S . gallinarum of the SE isolated and the SE seropositive groups were 41.7% and 47.6% from liver, 33.3% and 47.6% from spleen and 8.3% and 14.3% from cecum, respectively, and the SE nonisolated and the SE seronegative group were 63.6% and 64.7% from liver, 84.1% and 88.2% from spleen and 47.7% and 52.9% from cecum . The serological response of the SE isolated and the SE seropositive groups hardly changed from 75.0 and 81.8% before challenge to 75.0 and 85.7% after . But, the other two groups were found to be significantly higher after challenge and increased from 0 and 18.2% to 100% . Consequently, S . enteritidis preinfected chickens were found to be significant different in terms of mortality, weight gain, reisolation of S . gallinarum and serological response compared to noninfected chickens . Moreover, our study shows that S . enteritidis infected chickens appear strong competitive exclusion against the colonization of S . gallinarum. JOP, 2003 Nov, 4(6), 200 - 6 Pancreatic involvement in Salmonella infection; Pezzilli R et al.; CONTEXT: Salmonella has been identified as a causative agent of acute pancreatitis . OBJECTIVE: We prospectively evaluated the frequency of acute pancreatitis, pancreatic enzyme elevation and morphological pancreatic abnormalities in patients with Salmonella infection . SUBJECTS: Thirty consecutive patients with salmonellosis (Salmonella enterica serovar Enteritidis: n=25; Salmonella enterica serovar Typhimurium: n=5) and 30 sex- and age-matched healthy subjects were studied . MAIN OUTCOME MEASURES: All subjects underwent serum amylase and lipase determination and ultrasonography . RESULTS: None of the subjects developed acute pancreatitis . Two patients (6.7%) and two controls showed serum amylase activity above the upper reference limit whereas, in five patients (16.7%) and one control subject (3.3%), the serum lipase activity appeared above the upper reference limit . Salmonella infection significantly increased serum activity of lipase (P<0.001) while it did not significantly affect serum amylase levels (P=0.204) . Serum lipase activity was significantly higher in patients infected by Salmonella enterica serovar Typhimurium than in those infected by Salmonella enterica serovar Enteritidis (P=0.012) . Ultrasonography did not show pancreatic abnormalities in any of the subjects . CONCLUSIONS: Our data demonstrated an elevation of serum lipase activity in gastroenteritis due to Salmonella infection, but this elevation does not seem to have clinical significance . The elevation of serum lipase seems to be particularly related to infection from Salmonella enterica serovar Typhimurium. J Vet Sci, 2003 Aug, 4(2), 161 - 6 Biochemical characteristics and antimicrobials susceptibility of Salmonella gallinarum isolated in Korea; Lee YJ et al.; Fowl typhoid (FT) reported since 1992 in Korea is a septicemic disease of domestic birds caused by Salmonella gallinarum (S . gallinarum) . The purpose of this study was to investigate the biochemical characteristics and antimicrobials susceptibility of field isolates of S . gallinarum isolated by year in Korea . A total of 258 isolates of S . gallinarum from 1995 to 2001 showed the same pattern in the majority of biochemical test such as IMViC (indole, methyl red, Voges-Proskauer and citrate utilization), carbohydrate fermentation and amino acid decarboxylation, and these results were almost in accordance with the traditional biochemical characteristics of S . gallinarum strain . When the antimicrobial susceptibility test against 258 isolates of S . gallinarum was performed by the disk diffusion method using 12 antimicrobial agents, all isolates from 1995 appeared to be susceptible to all of the antimicrobial agents tested except for tetracycline and oxytetracycline, whereas the vast majority of isolates from 2001 showed the reduced susceptibility to ampicillin (13.0%), gentamicin (43.4%), kanamycin (69.6%), enrofloxacin (6.5%), ciprofloxacin (10.9%), norfloxacin (52.5%) and ofloxacin (82 . 6%) . The prevalence of the prevalence of completely resistant isolates resistant isolates to one or more drugs rapidly increased from 0% in 1995 to 93.5% in 2001 . The minimal concentrations range of the majority of antimicrobial agents to inhibit 50% (MIC50s) against S . gallinarum isolates increased from 0.06 approximately 8 microg/ml in 1997 to 2 approximately 256 microg/ml in 2001 . Especially, MIC50s for gentamicin and fluoroquinolones of isolates from 2001 increased over 10-fold than those of isolates from 1997 . Therefore, our results indicate that sorbitol fermentation and arginine decarboxylation showed the diversity by isolates and the vast majority of isolates from 2001 showed the reduced susceptibility to antimicrobials tested. J Vet Sci, 2003 Aug, 4(2), 143 - 9 Reference map of soluble proteins from Salmonella enterica serovar Enteritidis by two-dimensional electrophoresis; Park MR et al.; Protein identification by peptide mass fingerprinting using matrix-assisted laser desorption ionization time of fight (MALDI-TOF) mass spectrometry (MS) can analyze unambiguously identity of the spots from a 2-dimensional electrophoresis (2-DE) gel . This study developed a technique for 2-DE of Salmonella enterica serovar Enteritidis (S . enteritidis) by improving the dissolution conditions by 2-DE using a pH 4 - 7 immobilized pH gradient (IPG) strip . This report examines the protein components from the patterns of the S . enteritidis protein . The most abundant protein displayed a great number of clusters within the pH 4.5 - 7 range with a molecular mass ranging from 35-80 kDa . Some of these spots were identified as metabolic related enzymes . The protein fraction was also analyzed using an immobilized pH gradient strip . Different proteins were identified on the spot according to the elongation factors . In addition, this study showed that the 2-DE analysis of S . enteritidis provides useful information regarding the S . enteritidis proteome, and this approach might provide a strategy for identifying bacterial proteins using a proteome technology. Indian J Med Res, 2003 May, 117, 201 - 4 A prospective study of phage types & biotypes of Salmonella enterica serotype Typhi isolated from hospitalized children in Kolkata, India; Saha MR et al.; BACKGROUND & OBJECTIVES: Kolkata and its suburbs in eastern India faced an epidemic of typhoid fever in 1990 . A prospective, hospital and laboratory based study over a period of 12 yr (1990-2001), on the phage typing and biotyping pattern of Salmonella enterica serotype Typhi was carried out, to see if there has been a change . METHODS: A total of 338 S . enterica serotype Typhi isolates from 1491 blood samples were phage typed and biotyped . The mean age of isolation was calculated . RESULTS: The age distribution of subjects (neonates to 12 yr) has been analysed . Of the 338 (22.7%) isolates obtained, eight different S . enterica serotype Typhi phage types were detected . Biotype I (95.8%) was more prevalent as compared to biotype II (4.1%) . Phage type E1 was the commonest phage type in Kolkata and its suburbs . INTERPRETATION & CONCLUSION: The mean age at isolation was found to be 6.7 +/- 3.3 yr . Biotype I was predominant and it was of interest that all strains of phage type E1 belonged to biotype I. Radiats Biol Radioecol, 2003 Jul-Aug, 43(4), 428 - 31 {Influence of the indometafen radioprotector on the immune reactivity}; Mikhailov PP et al.; In the experiments on dogs and mice it was shown that indometophene could modify the immune status of the body . Specific and non-specific resistance of mice to E . coli infection increased after indometophene administration . At the same time higher titers of normal anti-salmonella antibodies in mice serum and a higher phagocytic activity of neutrophils in the peripheral blood in dogs were found . The influence of the preparation on the content of the complement and normal antibodies-hemagglutinins was less pronounced . It was suggested that the indometophene ability to bustle immune reactivity of the body played a certain role in the mechanism of its radioprotective effect. Can J Microbiol, 2003 Sep, 49(9), 531 - 7 Fitness cost of the green fluorescent protein in gastrointestinal bacteria; Rang C et al.; There are surprisingly few studies that have successfully used the green fluorescent protein (GFP) as a quantitative reporter in selection experiments screening for inducible bacterial promoters . One explanation is that GFP expression may confer a fitness cost for bacteria . To test this possibility, we monitored the doubling time in enteric bacteria expressing GFP . Four bacterial species, Escherichia coli, enterohaemorrhagic E . coli, Shigella flexneri, Salmonella typhi, and Vibrio cholerae, were examined . The level of GFP expression was varied by using a salt-inducible promoter . After accounting for the increase in doubling time resulting from elevated osmolarity, the doubling time of all bacteria was found to increase proportionally with GFP expression, and some strains were more affected than others . Cultures of the bacteria most affected by GFP exhibited a proportion of elongated cells, which suggests that GFP production could interfere with cell division in these strains . The results in this study show that GFP is costly to bacteria and suggest that overly active promoters should be difficult to obtain from a genomic promoter library . They also suggest that the chances of succeeding in using GFP as a reporter in selection experiments are increased by growing the bacteria for the fewest number of generations and by subduing the expression of GFP whenever possible, such as by using a low copy vector to clone the library. Clin Diagn Lab Immunol, 2003 Nov, 10(6), 1078 - 84 Mimotopes of the Vi antigen of Salmonella enterica serovar typhi identified from phage display peptide library; Tang SS et al.; The capsular polysaccharide Vi antigen (ViCPS) is an essential virulence factor and also a protective antigen of Salmonella enterica serovar Typhi . A random 12-mer phage-displayed peptide library was used to identify mimotopes (epitope analogues) of this antigen by panning against a ViCPS-specific monoclonal antibody (MAb) ATVi . Approximately 75% of the phage clones selected in the fourth round carried the peptide sequence TSHHDSHGLHRV, and the rest of the clones harbored ENHSPVNIAHKL and other related sequences . These two sequences were also obtained in a similar panning process by using pooled sera from patients with a confirmed diagnosis of typhoid fever, suggesting they mimic immunodominant epitopes of ViCPS antigens . Binding of MAb ATVi to the mimotopes was specifically blocked by ViCPS, indicating that they interact with the same binding site (paratope) of the MAb . Data and reagents generated in this study have important implications for the development of peptide-base diagnostic tests and peptide vaccines and may also provide a better understanding of the pathogenesis of typhoid fever. Euro Surveill, 2003 Oct, 8(10), 195 - 8 A regional outbreak of S . Enteritidis phage type 5, traced back to the flocks of an egg producer, Austria; Berghold C et al.; In the spring and summer of 2002, the Nationale Referenzzentrale fur Salmonellen (National Reference Centre for Salmonella - NRCS) in Austria noticed a cluster of human Salmonella enterica subsp . enterica ser . Enteritidis phage type 5 (S . Enteritidis PT5) infections in two neighbouring districts of Austria . Another small outbreak of S . Enteritidis PT5 infections that occurred in the same region in 1999 had been traced back to the flocks of a local egg producer (approximately 6 000 hens) . Attention was therefore again directed at this farm . The results of voluntary bacteriological examinations from the farm and further epidemiological investigations identified the same egg producer as the source of the second outbreak . The 70 human isolates of S . Enteritidis PT5 ascertained in 2002 represented a minority of all infections . It is realistic to estimate that several hundred infections occurred in the course of the 2002 outbreak . The farmer had not vaccinated new flocks against Salmonella since August 2001 . It is likely that the change in vaccination policy resulted in the reappearance of the S . Enteritidis PT5 infections . By the end of September 2002 the farmer had stopped selling untreated table eggs . In October 2002 only one isolate of S . Enteritidis PT5 was ascertained in the region. J Immunol Methods, 2003 Nov, 282(1-2), 83 - 91 The TUBEX typhoid test based on particle-inhibition immunoassay detects IgM but not IgG anti-O9 antibodies; Tam FC et al.; A serological test kit (TUBEX, IDL Biotech, Sweden) developed recently for the diagnosis of typhoid fever detects antibodies to the Salmonella enterica serovar Typhi lipopolysaccharide (LPS) O9 antigen . The antibodies are detected by their ability to inhibit the interaction between two types of reagent particles: (a) . indicator latex microspheres sensitized with an anti-O9 monoclonal antibody, and (b) . magnetic microspheres sensitized with S . typhi LPS . Following rapid mixing of the serum with these reagents and sedimentation of the magnetic particles by magnetic force, the concentration of indicator particles left in suspension provides a measure of the inhibition . Whereas it was previously assumed that both IgM and IgG antibodies could inhibit in the system, the present study reveals, surprisingly, that only the IgM antibodies do . It is not clear why IgG anti-O9 antibodies, both of mouse and human origin, do not inhibit, although these can bind to the LPS-sensitized magnetic particles as efficiently as the IgM antibodies . In addition, they can also inhibit very well in another detection system (ELISA) which uses a similar assay format and the same antibody and antigen reagents . Increasing the size of the LPS-sensitized microspheres made no difference; microscopic analysis of the TUBEX reaction mixture revealed that while the indicator particles bound abundantly to the IgG-aggregated LPS-sensitized particles, forming large clumps, these only formed a very light decoration on the IgM-aggregated particles . Thus, the TUBEX system is ideally suited for use in the diagnosis of infections as it allows IgM antibodies to be detected easily and rapidly from whole sera. J Vasc Surg, 2003 Nov, 38(5), 975 - 82 In situ reconstruction of septic aortic pseudoaneurysm due to Salmonella or Streptococcus microbial aortitis: long-term follow-up; Luo CY et al.; OBJECTIVE: This study was undertaken to illustrate the safety of in situ reconstruction of septic aortic pseudoaneurysm (SAP) secondary to microbial aortitis, with or without long-term antibiotic treatment . METHODS: Data for patients with SAP (11 abdominal, 4 thoracic) operated on between 1993 and 1999 were reviewed . Computed tomography and aortography showed septic pseudoaneurysm in all patients before surgery . After diagnosis of SAP, all patients underwent aneurysm resection and extensive debridement, with in situ prosthetic grafting or patch repair angioplasty . The graft in 10 of the 11 patients with abdominal SAP was also wrapped with an omental pedicle . In vitro active parenteral antibiotic therapy was prescribed for all patients for at least 2 to 8 weeks after surgery . RESULTS: All 15 patients had positive preoperative blood cultures or intraoperative tissue cultures for Salmonella spp (n = 12), viridans Streptococcus (n = 1), group G Streptococcus (n = 1), or Streptococcus pneumoniae (n = 1) . There were two perioperative deaths (13.3%), one 6 days after surgery and the other 19 days after surgery, and two late deaths, at 8 and 10 months after surgery, neither of which was related to aortic repair . One patient was unavailable for follow-up . The other 10 patients have been regularly followed up with abdominal ultrasound or computed tomography (mean, 84 months; range, 47-118 months) . To date, there has been no graft infection, thrombosis, false aneurysm, or subsequent aortic surgery in these 10 patients . CONCLUSION: SAP due to Salmonella and streptococcal microbial aortitis can be successfully treated with resection of the aneurysm and extensive debridement, followed by in situ prosthetic graft interposition or patch repair aortoplasty . This is a safe and effective treatment that may result in complete remission of SAP . Postoperative parenteral antibiotic therapy should be continued for 2 to 8 weeks . Although usually recommended, lifelong suppressive antibiotic therapy appears to be nonessential with this approach. Appl Environ Microbiol, 2003 Nov, 69(11), 6669 - 75 Induction and resuscitation of viable but nonculturable Salmonella enterica serovar typhimurium DT104; Gupte AR et al.; Salmonella enterica serovar Typhimurium DT104 11601 was tested for its ability to maintain viability in minimal, chemically defined solutions . Periodic monitoring of growth and survival in microcosms of different ion concentrations, maintained at various temperatures, showed a gradual decline in culturable organisms ( approximately 235 days) at 5 degrees C . Organisms maintained at a higher temperature (21 degrees C) showed continuous, equivalent CFU per milliliter ( approximately 10(6)) up to 400 days after inoculation . Fluorescence microscopy with Baclight revealed that nonculturable cells were actually viable, while observations with scanning electron microscopy showed that the cells had retained their structural integrity . Temperature upshift (56 degrees C +/- 0.5, 15 s) of the nonculturable organisms (5 degrees C) in Trypticase soy broth followed by immediate inoculation onto Trypticase soy agar (TSA) gave evidence of resuscitation . Interestingly, S . enterica serovar Typhimurium DT104 from the microcosms at either 5 degrees C (1 to 200 days) or 21 degrees C (1 to 250 days) did not show enhanced growth after intermittent inoculation onto catalase-supplemented TSA . Furthermore, cells from 21 degrees C microcosms exposed to oxidative and osmotic stress showed greater resistance to stresses over increasing times of exposure than did recently grown cells . It is possible that the exceptional survivability and resilience of this particular strain may in part reflect the growing importance of this multidrug-resistant organism, in general, as a cause of intestinal disease in humans . The fact that S . enterica serovar Typhimurium DT104 11601 is capable of modifying its physiological characteristics, including entry into and recovery from the viable but nonculturable state, suggests the overall possibility that S . enterica serovar Typhimurium DT104 may be able to respond uniquely to various adverse environmental conditions. Int J Antimicrob Agents, 2003 Nov, 22(5), 537 - 40 In vitro fluoroquinolone-resistant mutants of Salmonella enterica serotype Enteritidis: analysis of mechanisms involved in resistance; Soto SM et al.; This study analysed the mechanisms involved in the acquisition of resistance to quinolones in mutants obtained in vitro of Salmonella enterica serotype Enteritidis . Two nalidixic acid-resistant (minimal inhibitory concentrations, MIC>256 mg/l), ciprofloxacin-susceptible (MIC 0.5 mg/l) clinical isolates of Salmonella Enteritidis with a mutation at amino acid codon Ser-83 of the gyrA gene were grown on plates containing increasing concentrations of ciprofloxacin . The increase in MIC to ciprofloxacin, sparfloxacin and trovafloxacin was totally or partially associated with over-expression of an AcrAB-like efflux pump . In addition, unidentified mechanism(s) may have been involved in the increased MIC to these antimicrobials . This study demonstrated that AcrAB-like efflux pumps appear to play a relevant role in the increase in MIC to some quinolones although, other, as yet undefined, mechanisms may be involved. Int J Antimicrob Agents, 2003 Nov, 22(5), 487 - 91 Trends in antimicrobial drug resistance in Salmonella enterica serotypes Typhi and Paratyphi A isolated in Europe, 1999-2001; Threlfall EJ et al.; Results of antimicrobial sensitivity tests for strains of Salmonella enterica serotypes Typhi and Paratyphi A isolated from patients in ten European countries between 1999 and 2001 have been transferred electronically to the Enter-net surveillance hub . For Typhi between 22 and 29% of isolates were multiresistant (to four drugs or more) with decreased susceptibility to ciprofloxacin (MIC 0.25-1.0 mg/l) increasing from 20% in 1999 to 26% in 2001 . Nineteen of 169 (11%) strains with decreased ciprofloxacin susceptibility were sensitive to nalidixic acid . For Paratyphi A multiple resistance increased from 9% in 1999 to 25% in 2001 and decreased ciprofloxacin susceptibility from 6 to 17% . Clinicians should be aware of the possibility of treatment failures when fluoroquinolones are used as the first-line drug for infections with Typhi and Paratyphi A, particularly for patients recently returning from areas where drug-resistant strains are endemic. Toxicol In Vitro, 2003 Oct-Dec, 17(5-6), 731 - 6 Use of in vitro assays to assess the potential antigenotoxic and cytotoxic effects of saffron (Crocus sativus L.); Abdullaev FI et al.; Saffron is harvested from the dried, dark red stigmas of Crocus sativus L . flowers . It is used as a spice for flavoring and coloring food and as a perfume . It is often used for treating several diseases . We assessed the antimutagenic, comutagenic and cytotoxic effects of saffron and its main ingredients using the Ames/Salmonella test system, two well known mutagens (BP, 2AA), the in vitro colony formation assay and four different cultured human normal (CCD-18Lu) and malignant (HeLa, A-204 and HepG2) cells . When only using the TA98 strain in the Ames/Salmonella test system, saffron showed non-mutagenic, as well as non-antimutagenic activity against BP-induced mutagenicity, and demonstrated a dose-dependent co-mutagenic effect on 2-AA-induced mutagenicity . The saffron component responsible for this unusual comutagenic effect was safranal . In the in vitro colony formation test system, saffron displayed a dose-dependent inhibitory effect only against human malignant cells . All isolated carotenoid ingredients of saffron demonstrated cytotoxic activity against in vitro tumor cells . Saffron crocin derivatives possessed a stronger inhibitory effect on tumor cell colony formation . Overall, these results suggest that saffron itself, as well as its carotenoid components might be used as potential cancer chemopreventive agents. Br Poult Sci, 2003 Sep, 44(4), 577 - 85 Comparison of natural resistance in seven genetic groups of meat-type chicken; Kramer J et al.; 1 . Several studies have shown that genetic variation exists in response to various Salmonella strains in mammals and poultry . In the current study immunocompetence traits related to natural resistance to Salmonella were measured in 7 genetic groups of meat-type chickens (in total 296 chickens involved) . 2 . Variables were measured of both innate (phagocytic activity) and adaptive immune responses that are important after a natural or experimental Salmonella enteritidis infection . Two traditional Old Dutch Breeds (groups 1 and 2), four commercial broiler groups (groups 3 to 6), and one experimental broiler group (group 7) were used . In two periods, birds of each group were killed for examination at ages between 14 and 35 d post hatch . 3 . Significant differences between groups were found for most immune variables measured, with significant correlations between several of them . All groups produced an adequate immune response, of either the innate or the adaptive type . 4 . In the current study, group 2 showed the highest overall natural resistance, though none of the groups was uniformly superior with respect to all traits measured . 5 . In conclusion, for reliable measurements of general immunocompetence or resistance to Salmonella, for example, it is important to measure several aspects of the immune system. Gig Sanit, 2003 Sep-Oct, (5), 61 - 3 {Benzimidazole derivative inhibition of the mutagenic activity of 2-aminoanthracene}; Zinov'eva VN et al.; The antimutagenic activity of a new benzimidazole derivative that has antioxidative properties was found in the Salmonella/microsome test . This compound reduced the level histidine revertants induced by the promutagen and carcinogen 2-aminoanthracene . Inhibition of the mutagenicity of 2-aminoanthracene appears to be associated with the inactivation of its genotoxic metabolites . The capacity of the benzimidazole derivative for antimutagenic effects is possibly due to a dihydroxyphenyl radical that is present in its structure. Mol Immunol, 2003 Dec, 40(9), 603 - 10 Priming by recombinant chicken interleukin-2 induces selective expression of IL-8 and IL-18 mRNA in chicken heterophils during receptor-mediated phagocytosis of opsonized and nonopsonized Salmonella enterica serovar enteritidis; Kogut MH et al.; Heterophils, the principal avian polymorphonuclear leukocytes (PMNs) equivalent to the mammalian neutrophil, function as professional phagocytes against bacterial infections, mediate acute inflammation, and respond to cytokine stimulation to aid in regulation of innate host defenses . Interleukin-2 (IL-2) has been found to exercise an array of biological effects on other cell types besides T lymphocytes, including NK cells, B cells, monocytes, and neutrophils . In the present experiments, using real-time quantitative RT-PCR, we evaluated the role of rChIL-2 as a priming mediator controlling heterophil responses at the level of gene transcription by examining the expression of mRNA for pro-inflammatory (IL-1beta, IL-6, IL-8) and Th1 (IL-18 and IFN-gamma) cytokine genes following stimulation with phagocytosis agonists; i.e., opsonized and nonopsonized Salmonella enteritidis . Peripheral blood heterophils were isolated and incubated with rChIL-2 from transfected COS cells . rChIL-2 selectively primed the heterophils for an increase in transcription of the pro-inflammatory cytokine IL-8 and of the Th1 cytokine IL-18 induced by all three phagocytic agonists . Although rChIL-2 priming modulated the expression of specific cytokine mRNA in heterophils stimulated by different phagocytic agonists, the rChIL-2 by itself did not directly induce gene expression of either the pro-inflammatory or Th1 cytokines . We propose that rChIL-2 could be priming heterophils solely to function as more efficient innate effector cells to limit bacterial growth through the selective increase of IL-8 and IL-18 gene expression. New Microbiol, 2003 Oct, 26(4), 363 - 73 Occurrence of Salmonella typhi and Salmonella paratyphi in Jordan; Battikhi MN; In order to justify the surveillance control system and hygiene policy in Jordan, this study evaluated the occurrence of diarrhoea during the period 1988-2000, focusing on cases caused by Salmonella typhi and Salmonella paratyphi . From January 1988 to December 2000, the number of notified diarrhoeal cases by the Ministry of Health in Jordan was 1,399,563 million . Other groups of patients confined to the Governorate of Amman was diagnosed at Al-Battikhi Medical Laboratories . One-way ANOVA and Least Significant Difference (LSD) were carried out for statistical analysis . The number of reported diarrhea cases was 1,399,563, 53.0% were males, and 47.0% were females, among them, 80.3% were < 20 years and 19.7%, were > 20 years . Out of 245,255 patients tested for S . typhi and S . pararyphi, positive stool culture were 1992 (0.6%) . Out of these, 960 (48.2%) were males and 1,032 (51.8%) were females (P = 0.028) . The highest incidence rate (10.8) was observed in the year 1993, while the lowest incidence rate (0.9) was found in year 2000 . A significant difference (P < 0.001) was found between the number of S . typhi and S . Paratyphi cases and year . The seasonal variation was also found to be significant (P < 0.0001), with the summer period showing the highest incident rate . A significant difference (P < 0.001) was observed between number of typhoid and paratyphoid cases and districts . A significance difference between number of typhoid and paratyphoid cases with age and sex . The group most affected was school age and adolescence . The demographic situation plays an important role in reporting typhoid and paratyphoid cases, where there might be an urgent indication for a better surveillance control system on water resources and disposal systems . S . typhi and S . paratyphi antibiotics resistance pattern showed they were resistant to tetracycline (56.0%, 58.0%), ampicillin (45.0%, 48.0%), trimethoprim (43.0%, 47.0%), cephtazidime (12.0%, 13.5%) chloramphenicol (6.8%, 7.2%), gentamycin (3.0%, 4.0%) neomycin (2.1 . 1.8%), calvulanic acid (augmentin (1.4%, 2.2%) and norofloxacin (0.92%, 1.1%) . Susceptibility to amikacin, ciprofloxacin, cetfriaxone, ofloxacine, imepenim, cefixime and cefotaxime was 100.0% . The increase in percentage of antibiotic resistant strain might indicate a need for a further prescribing policy for treatment. Nat Struct Biol, 2003 Dec, 10(12), 1064 - 73 Epub 2003 Nov 02. CysG structure reveals tetrapyrrole-binding features and novel regulation of siroheme biosynthesis; Stroupe ME et al.; Sulfur metabolism depends on the iron-containing porphinoid siroheme . In Salmonella enterica, the S-adenosyl-L-methionine (SAM)-dependent bismethyltransferase, dehydrogenase and ferrochelatase, CysG, synthesizes siroheme from uroporphyrinogen III (uro'gen III) . The reactions mediated by CysG encompass two branchpoint intermediates in tetrapyrrole biosynthesis, diverting flux first from protoporphyrin IX biosynthesis and then from cobalamin (vitamin B(12)) biosynthesis . We determined the first structure of this multifunctional siroheme synthase by X-ray crystallography . CysG is a homodimeric gene fusion product containing two structurally independent modules: a bismethyltransferase and a dual-function dehydrogenase-chelatase . The methyltransferase active site is a deep groove with a hydrophobic patch surrounded by hydrogen bond donors . This asymmetric arrangement of amino acids may be important in directing substrate binding . Notably, our structure shows that CysG is a phosphoprotein . From mutational analysis of the post-translationally modified serine, we suggest a conserved role for phosphorylation in inhibiting dehydrogenase activity and modulating metabolic flux between siroheme and cobalamin pathways. J Bacteriol, 2003 Nov, 185(22), 6732 - 5 A mutation in the essential gene gmk (encoding guanlyate kinase) generates a requirement for adenine at low temperature in Salmonella enterica; Beck BJ et al.; In Salmonella enterica serovar Typhimurium, gmk encodes guanylate kinase, an essential enzyme involved in the synthesis and salvage of guanine nucleotides . Here we report the isolation of a mutation in gmk that results in a nutritional requirement for adenine at low temperature . Comparisons of kinetic parameters from the wild-type and mutant Gmk enzymes revealed that the mutant enzyme had a more than 20-fold-higher Km for ATP than the wild-type enzyme . The growth dependence of the mutant on temperature and/or adenine could not be explained as a direct result of this kinetic difference . We propose a model in which previously described regulatory effects of GMP are responsible for these phenotypes. J Bacteriol, 2003 Nov, 185(22), 6497 - 506 Negative osmoregulation of the Salmonella ompS1 porin gene independently of OmpR in an hns background; Flores-Valdez MA et al.; The ompS1 gene encodes a quiescent porin in Salmonella enterica serovars Typhi and Typhimurium . By using random mariner transposon mutagenesis, mutations that caused derepression of ompS1 expression were isolated, one in S . enterica serovar Typhi and two in S . enterica serovar Typhimurium . All of them mapped in the hns gene in the region coding for the carboxy terminus of the H-NS nucleoid protein . The derepressed ompS1 expression was subject to negative regulation at high osmolarity, both in the presence and in the absence of OmpR . This observation was possible due to the fact that there are two promoters: P1, which is OmpR dependent, and P2, which does not require OmpR for activation (rather, OmpR represses P2) . The sequences upstream from position -88, a region previously shown to be involved in the negative regulation of ompS1, can form a static bend, and the integrity of this region was required for function and binding of H-NS and for osmoregulation, as determined with gene reporter fusions of different lengths and with a 31-bp deletion mutant . This is consistent with the notion that this region determines a structure required for repression . Hence, ompS1 shares negative regulation by H-NS with other loci, such as the bgl operon and the ade gene. Acta Microbiol Pol, 2003, 52(2), 183 - 90 The molecular characterisation of the extended spectrum beta-lactamase (ESBL) producing strain of Salmonella enterica serovar Mbandaka isolated in Poland; Gierczynski R et al.; The molecular attributes of the first ESBL producing isolate 267/99 of Salmonella enterica serovar Mbandaka isolated in 1999 in Poland were characterised . Tested strain produced CTX-M-3 and TEM-1 beta-lactamases, encoded by genes localised on the about 80 kb self-transferable plasmid, harbouring the 2 kb class 1 integron carrying aadA2 gene. FEMS Microbiol Lett, 2003 Oct 24, 227(2), 211 - 7 Delivery of a heterologous antigen by a registered Salmonella vaccine (STM1); Bachtiar EW et al.; STM1 is an aro A(-) attenuated mutant of Salmonella enterica serovar Typhimurium, and is a well-characterised vaccine strain available to the livestock industry for the prevention of salmonellosis in chickens . This strain has potential for heterologous antigen delivery, and here we show that the strain can be used to deliver a model antigen, ovalbumin, to immune cells in vitro and in vivo . Two plasmid constructs expressing the ovalbumin gene were utilised, one of which uses a prokaryotic promoter and the other the CMV promoter (DNA vaccine) . In vitro, STM1 carrying ovalbumin-encoding plasmids was able to invade dendritic cells and stimulate a CD8(+) cell line specific for the dominant ovalbumin epitope, SIINFEKL . In vivo, spleen cells were responsive to SIINFEKL after vaccination of mice with ovalbumin-encoding plasmids in STM1, and finally, humoral responses, including IgA, were induced after vaccination. Environ Toxicol Chem, 2003 Nov, 22(11), 2576 - 84 Assessment of the mutagenic potency of sewage sludges contaminated with polycyclic aromatic hydrocarbons by an Ames sludges for fluctuation assay; Perez S et al.; The mutagenicity of crude extracts and subfractions of two samples of a reference sewage sludge material and two sewage sludges from two wastewater treatment plants (WWTP), one urban and the other one urban mixed with industrial, was assessed using an Ames fluctuation assay based on 384-well microtiter plates with liquid cultures . Crude extracts of sludges were obtained by ultrasonic extraction with dichloromethane/methanol, and further column fractionation yielded two fractions, one of which containing mutagenic polycyclic aromatic hydrocarbons (PAHs) . Quantitative analysis performed by gas chromatography-mass spectrometry gave sum concentrations of the 16 PAHs listed as priority pollutants by the U.S . Environmental Protection Agency at levels between 1,305 and 2,442 microg/kg . Subjecting crude extracts and column fractions to the mutagenicity assay with Salmonella strains TA98 and TA 100 provided good qualitative correlation between the presence of mutagenic PAH and the induction of gene mutations . In general, the crude extracts and the PAH-fractions induced positive responses in the assay with both bacterial strains on metabolic activation by S9 rat-liver homogenate, whereas direct-acting mutagens were not detectable . In the assay with the real sludge samples of two different WWTPs, TA98 proved to be more sensitive than TA100; however, similar sensitivities of the tester strains were observed for two reference sewage sludge materials of the same origin . The outcomes of the Ames fluctuation assay demonstrated its performance as a cost-effective and relatively rapid screening tool to assess the genotoxic potential of complex environmental samples. Jpn J Infect Dis, 2003 Aug, 56(4), 156 - 7 Combination effect of ciprofloxacin and gentamicin against clinical isolates of Salmonella enterica serovar typhi with reduced susceptibility to ciprofloxacin; Mandal S et al.; The present study evaluated the in vitro efficacy of ciprofloxacin (CPFX) in combination with gentamicin (GM) using agar dilution checkerboard method against six blood culture isolates of Salmonella enterica serovar Typhi with CPFX minimum inhibitory concentration (MIC) values of 0.75 - 1.25 microg/ml and GM MIC values of 0.75 - 2 microg/ml . When used in combination, the fractional inhibitory concentration (FIC) values of CPFX and GM for the isolates ranged from 0.008 - 0.032 microg/ml and 0.1 - 0.2 microg/ml, respectively . The range of the FIC index from 0.121 - 0.216 indicated the synergistic effect between CPFX and GM for all the isolates . The time-kill method, which showed a 2.64 log(10) decrease in CFU/ml between the combination and its more active compound, also established synergism between CPFX and GM against one isolate employed in the method . These results may be helpful in making clinical decisions in the treatment of enteric fever due to the infection of multidrug resistant S . enterica serovar Typhi. Jpn J Infect Dis, 2003 Aug, 56(4), 151 - 5 Multiplex polymerase chain reaction assay for selective detection of Salmonella enterica serovar typhimurium; Lim YH et al.; A multiplex polymerase chain reaction (PCR) assay was developed for the identification of Salmonella enterica serovar Typhimurium . Three sets of primers were designed for detecting O4, H:i, and H:1,2 antigen genes from the antigen-specific genes rfbJ, fliC, and fljB, respectively . These were evaluated in a multiplex PCR assay by using DNAs from S . enterica serovar Typhimurium, 15 other Salmonella serovars, and 8 non-Salmonella enteric pathogens . Multiplex PCR proved to be capable of identifying S . enterica serovar Typhimurium specifically and differentiating it from other Salmonella serovars in addition to non-Salmonella enteric pathogens . Thus, this multiplex PCR assay can be practically applied to the identification of S . enterica serovar Typhimurium. Vet Res Commun, 2003 Sep, 27(6), 425 - 32 55 kb plasmid and virulence-associated genes are positively correlated with Salmonella enteritidis pathogenicity in mice and chickens; Bakshi CS et al.; Twenty-four strains of Salmonella enteritidis, isolated from several outbreaks of salmonellosis from different poultry farms in India, were checked for the plasmid profile and detection of virulence gene(s) by PCR . Most of the strains contained only a single plasmid of 55 kb . Additional plasmids of 23.2 kb and 8.7 kb were seen in one of the strains, and another strain carried only two plasmids of 23.2 kb and 8.7 kb . Four strains did not carry any plasmid . PCR amplification showed the presence of virulence-associated genes in all the isolates harbouring the 55 kb plasmid . Intraperitoneal inoculation of mice, with most of the strains carrying the 55 kb plasmid, caused 100% mortality . Most strains lacking the 55 kb plasmid were avirulent . In chickens, oral inoculation of the S . enteritidis strains carrying the 55 kb plasmid produced 40-100% mortality, with characteristic signs of salmonellosis . Oral inoculation of strains lacking the 55 kb plasmid did not cause any mortality . Hence, it appears that the large plasmid of S . enteritidis probably contributes towards virulence in mice and chickens. Drug Chem Toxicol, 2003 Nov, 26(4), 245 - 57 Mutagenicity assay in Salmonella for thirteen 2-substituted-1 H-phenanthro (9,10-d) imidazoles; Zeytinoglu H et al.; Some 2-substituted-1 H-phenanthro {9,10-d} imidazole compounds synthesized as a predrugs were tested in mutagenicity assays in Salmonella strains TA97, TA98, and TA100 using a plate incorporation assay both with and without S9 mix . The 10 substances were mutagenic in TA97 and five of them were mutagenic only with metabolic activation, whereas one of them did not require the addition of S9 . The eight substances were mutagenic in TA98 only with S9 . For TA100, seven substances showed positive results both with and without S9, however another four required S9, whereas only one of them did not required metabolic activation . In summary, all of 13 substances derived from phenanthro {9,10-d} imidazole were found to be mutagenic for at least one or two of the three strains and their mutagenicity are discussed. Int J Food Microbiol, 2003 Dec 15, 89(1), 51 - 65 Effect of acid adaptation on inactivation of Salmonella during drying and storage of beef jerky treated with marinades; Calicioglu M et al.; This study evaluated the influence of pre-drying marinade treatments on inactivation of acid-adapted or nonadapted Salmonella on beef jerky during preparation, drying and storage . The inoculated (five-strain composite, 6.0 log CFU/cm2) slices were subjected to the following marinades (24 h, 4 degrees C) prior to drying at 60 degrees C for 10 h and aerobic storage at 25 degrees C for 60 days: (1) no marinade, control (C), (2) traditional marinade (TM), (3) double amount of TM modified with added 1.2% sodium lactate, 9% acetic acid, and 68% soy sauce with 5% ethanol (MM), (4) dipping into 5% acetic acid and then TM (AATM), and (5) dipping into 1% Tween 20 and then into 5% acetic acid, followed by TM (TWTM) . Bacterial survivors were determined on tryptic soy agar with 0.1% pyruvate and xylose-lysine-tergitol 4 (XLT4) agar . Results indicated that drying reduced bacterial populations in the order of pre-drying treatments TWTM (4.8-6.0 log CFU/cm2)> or =AATM> or =MM>TM> or =C (2.6-5.0 log CFU/cm2) . Nonadapted Salmonella were significantly (P<0.05) more resistant to inactivation during drying than acid-adapted Salmonella in all treatments . Bacterial populations decreased below the detection limit (-0.4 log CFU/cm2) as early as 7 h during drying or remained detectable even after 60 days of storage, depending on acid adaptation, pre-drying treatment, and agar media . The results indicated that acid adaptation may not cause increased resistance of Salmonella to the microbial hurdles involved in jerky processing and that use of modified marinades in manufacturing jerky may improve the effectiveness of drying in inactivating Salmonella. Mol Cell Probes, 2003 Oct, 17(5), 215 - 21 Comparison of culture, polymerase chain reaction (PCR), TaqMan Salmonella, and Transia Card Salmonella assays for detection of Salmonella spp . in naturally-contaminated ground chicken, ground turkey, and ground beef; Fratamico PM; Four types of assays were evaluated for the detection of Salmonella spp . in retail ground chicken (86 packages), ground turkey (104 packages), and ground beef (54 packages) . Two 25 g samples from each package were separately subjected to pre-enrichment in buffered peptone water for 20 h at 37 degrees C followed by enrichment in Rappaport Vassiliadis (RV) broth for 20 h at 42 degrees C . The RV enrichments were plated onto Rambach agar, Rainbow Agar Salmonella, and XLT4 agar, and were also tested by a PCR assay targeting the Salmonella invA gene, as well as by the TaqMan Salmonella PCR assay . Additionally, the RV enrichments were tested using the Transia Card Salmonella immunoassay . Results showed that 16.8, 24.0, 28.8, and 26.4% of turkey samples were positive for Salmonella spp . by culture, PCR, TaqMan PCR, and Transia Card Salmonella assays, respectively . Eighteen, 28.5, 35.5, and 34.9% of chicken samples were positive by culture, PCR, TaqMan PCR, and Transia Card Salmonella assays, respectively, and 6.5, 6.5, 6.5, and 18.5% of ground beef samples were positive by the four assays, respectively . Analysis of the data using the kappa statistic showed that there was substantial to excellent agreement between the PCR and TaqMan PCR assays and between the PCR and culture assays (kappa coefficients ranging from 0.67 to 0.87), while there was poor to fair agreement between the results of the Transia Card Salmonella assay and the other methods (kappa coefficients ranging from 0.28 to 0.32) . Overall, results showed that the PCR-based assays were more sensitive than the culture method, and the culture and PCR-based assays were more specific than the immunoassay for detection of Salmonella in ground chicken, turkey, and beef due to the occurrence of false positive results using the immunoassay. Microb Pathog, 2003 Dec, 35(6), 279 - 84 Salmonella enterica serovar Dublin strains which are Vi antigen-positive use type IVB pili for bacterial self-association and human intestinal cell entry; Morris C et al.; Some strains of Salmonella enterica serovar Dublin are Vi antigen-positive . S . enterica serovar Typhi uses Type IVB pili, encoded adjacent to the viaB locus required for Vi antigen synthesis, to facilitate both eukaryotic cell attachment and bacterial self-association under conditions that favour DNA supercoiling . These pilus-mediated events may be important in typhoid fever pathogenesis . A survey of 17 isolates of S . enterica serovar Dublin showed that all strains which carried the viaB region also carried a serovar Typhi-like Type IVB pil operon, and all serovar Dublin Vi antigen-negative isolates lacked the pil operon . The pil operon was completely sequenced from one of the Vi(+) serovar Dublin strains, and was almost identical (4 nt changes; 3 aa changes, in over 10 kb) to that of serovar Typhi . A pilS mutant of one serovar Dublin strain was constructed, and shown to invade cultured human intestinal INT407 cells to an extent only 20% that of the wild-type parent . Purified prePilS protein inhibited INT407 cell entry by serovar Dublin . The wild-type serovar Dublin strain, but not the pilS mutant, self-associated . The data suggest that the serovar Dublin Type IVB pil operon may increase the human-invasiveness of serovar Dublin, compared to pil-free strains. Acta Neurochir (Wien), 2003 Oct, 145(10), 919 - 21; discussion 921 Salmonella enteritidis causing brain abscess and coxitis following intracranial surgery; Schroder J et al.; We report the case of a 46-year-old woman who underwent surgery for an adamantinous craniopharyngeoma (WHO grade I) . The postoperative course, during which the patient received 16 mg/day of dexamethasone, was initially uneventful . After a fortnight the patient developed infectious signs and an intracranial abscess at the operation site with simultaneous purulent coxitis . Both the intracranial abscess and the coxitis were evacuated and drained . In tissue samples and pus obtained during re-craniotomy and during surgery on the hip, Salmonella enteritidis was detected by cultivation . Salmonella enteritidis was also isolated from several stool specimens . There was no known salmonellosis in the patient's medical history . She recovered as a result of antibiotic treatment with ciprofloxacin and chloramphenicol . The intracranial abscess healed without leaving any neurological deficit . Unfortunately the left hip subsequently required further surgery, culminating in removal of the entire femoral head . Prosthetic replacement could not yet be performed due to the recurrent septic course of the hip . Our case illustrates a serious complication with presumed haematogenous spread of the infection from a pre-existing asymptomatic and unknown colon infection . The immunosuppressive effect of corticosteroids in the treatment of the brain neoplasm might have been a contributing factor to the sudden exacerbation of the latent infection. Antimicrob Agents Chemother, 2003 Nov, 47(11), 3640 - 3 Multiple-drug resistance in D-tartrate-positive Salmonella enterica serovar paratyphi B isolates from poultry is mediated by class 2 integrons inserted into the bacterial chromosome; Miko A et al.; The presence of integrons in 85 multiresistant German isolates of the predominating Salmonella enterica subsp . enterica serovar Paratyphi B dT(+) clone was investigated . All isolates possessed a chromosomally located Tn7-like class 2 integron carrying the same dfrA1-sat1-aadA1 array of gene cassettes . Only four isolates (4.7%) revealed an additional class 1 integron with two strains each containing the aadA1 or dfrA1-aadA1 gene cassettes. Antimicrob Agents Chemother, 2003 Nov, 47(11), 3567 - 73 Mutations in topoisomerase genes of fluoroquinolone-resistant salmonellae in Hong Kong; Ling JM et al.; A total of 88 salmonella isolates (72 clinical isolates for which the ciprofloxacin MIC was >0.06 microg/ml, 15 isolates for which the ciprofloxacin MIC was < or =0.06 microg/ml, and Salmonella enterica serotype Typhimurium ATCC 13311) were studied for the presence of genetic alterations in four quinolone resistance genes, gyrA, gyrB, parC, and parE, by multiplex PCR amplimer conformation analysis . The genetic alterations were confirmed by direct nucleotide sequencing . A considerable number of strains had a mutation in parC, the first to be reported in salmonellae . Seven of the isolates sensitive to 0.06 micro g of ciprofloxacin per ml had a novel mutation at codon 57 of parC (Tyr57-->Ser) which was also found in 29 isolates for which ciprofloxacin MICs were >0.06 micro g/ml . Thirty-two isolates had a single gyrA mutation (Ser83-->Phe, Ser83-->Tyr, Asp87-->Asn, Asp87-->Tyr, or Asp87-->Gly), 34 had both a gyrA mutation and a parC mutation (29 isolates with a parC mutation of Tyr57-->Ser and 5 isolates with a parC mutation of Ser80-->Arg) . Six isolates which were isolated recently (from 1998 to 2001) were resistant to 4 micro g of ciprofloxacin per ml . Two of these isolates had double gyrA mutations (Ser83-->Phe and Asp87-->Asn) and a parC mutation (Ser80-->Arg) (MICs, 8 to 32 microg/ml), and four of these isolates had double gyrA mutations (Ser83-->Phe and Asp87-->Gly), one parC mutation (Ser80-->Arg), and one parE mutation (Ser458-->Pro) (MICs, 16 to 64 micro g/ml) . All six of these isolates and those with a Ser80-->Arg parC mutation were S . enterica serotype Typhimurium . One S . enterica serotype Typhi isolate harbored a single gyrA mutation (Ser83-->Phe), and an S . enterica serotype Paratyphi A isolate harbored a gyrA mutation (Ser83-->Tyr) and a parC mutation (Tyr57-->Ser); both of these isolates had decreased susceptibilities to the fluoroquinolones . The MICs of ciprofloxacin, levofloxacin, and sparfloxacin were in general the lowest of those of the six fluoroquinolones tested . Isolates with a single gyrA mutation were less resistant to fluoroquinolones than those with an additional parC mutation (Tyr57-->Ser or Ser80-->Arg), while those with double gyrA mutations were more resistant. Infect Immun, 2003 Nov, 71(11), 6680 - 5 Secretion of the orgC gene product by Salmonella enterica serovar Typhimurium; Day JB et al.; HilA activates the transcription of genes on Salmonella pathogenicity island 1 (SPI1), which encodes a type III secretion system (TTSS) . Previous studies showed that transposon insertions in orgC, a gene located on SPI1, increase hilA expression . We characterize the orgC gene product and show that it is secreted via the SPI1 TTSS . We propose a model whereby OrgC functions as a secreted repressor of the SPI1 virulence genes. Infect Immun, 2003 Nov, 71(11), 6653 - 7 Toll-like receptor expression in C3H/HeN and C3H/HeJ mice during Salmonella enterica serovar Typhimurium infection; Totemeyer S et al.; Here, we have investigated the mRNA expression of Toll-like receptor 2 (TLR-2), TLR-4, and MD-2 in spleens and livers of C3H/HeN mice (carrying wild-type TLR-4) and C3H/HeJ mice (carrying mutated TLR-4) in response to Salmonella infection . During Salmonella infections, TLR-4 is activated, leading to increased TLR-2 and decreased TLR-4 expression. Infect Immun, 2003 Nov, 71(11), 6610 - 4 Commensal bacteria increase invasion of intestinal epithelium by Salmonella enterica serovar Typhi; Lyczak JB; The intestinal microflora consists of a heterogeneous population of microorganisms and has many effects on the health status of its human host . Here, it is shown that the products of certain strains of bacteria normally present in the intestinal microflora are able to trigger redistribution of the cystic fibrosis transmembrane conductance regulator (CFTR) protein in epithelial cells . CFTR is used by Salmonella enterica serovar Typhi as a receptor on epithelial cells which mediate the translocation of this microorganism to the gastric submucosa . Serovar Typhi-epithelial cell adhesion and CFTR-dependent invasion by serovar Typhi of epithelial cells were increased following commensal-mediated CFTR redistribution . These data suggest that commensal microorganisms present in the intestinal lumen can affect the efficiency of serovar Typhi invasion of the intestinal submucosa . This could be a key factor influencing host susceptibility to typhoid fever. Infect Immun, 2003 Nov, 71(11), 6582 - 90 CapG(-/-) mice have specific host defense defects that render them more susceptible than CapG(+/+) mice to Listeria monocytogenes infection but not to Salmonella enterica serovar Typhimurium infection; Parikh SS et al.; Loss of the actin filament capping protein CapG has no apparent effect on the phenotype of mice maintained under sterile conditions; however, bone marrow-derived macrophages from CapG(-/-) mice exhibited distinct motility defects . We examined the ability of CapG(-/-) mice to clear two intracellular bacteria, Listeria monocytogenes and Salmonella enterica serovar Typhimurium . The 50% lethal dose of Listeria was 10-fold lower for CapG(-/-) mice than for CapG(+/+) mice (6 x 10(3) CFU for CapG(-/-) mice and 6 x 10(4) CFU for CapG(+/+) mice), while no difference was observed for Salmonella: The numbers of Listeria cells in the spleens and livers were significantly higher in CapG(-/-) mice than in CapG(+/+) mice at days 5 to 9, while the bacterial counts were identical on day 5 for Salmonella-infected mice . Microscopic analysis revealed qualitatively similar inflammatory responses in the spleens and livers of the two types of mice . Specific immunofluorescence staining analyzed by fluorescence-activated cell sorting revealed similar numbers of macrophages and dendritic cells in infected CapG(-/-) and CapG(+/+) spleens . However, analysis of bone marrow-derived macrophages revealed a 50% reduction in the rate of phagocytosis of Listeria in CapG(-/-) cells but a normal rate of phagocytosis of Salmonella: Stimulation of bone marrow-derived dendritic cells with granulocyte-macrophage colony-stimulating factor resulted in a reduction in the ruffling response of CapG(-/-) cells compared to the response of CapG(+/+) cells, and CapG(-/-) bone-marrowed derived neutrophils migrated at a mean speed that was nearly 50% lower than the mean speed of CapG(+/+) neutrophils . Our findings suggest that specific motility deficits in macrophages, dendritic cells, and neutrophils render CapG(-/-) mice more susceptible than CapG(+/+) mice to Listeria infection. Infect Immun, 2003 Nov, 71(11), 6446 - 52 Type 1 fimbriae of Salmonella enterica serovar Typhimurium bind to enterocytes and contribute to colonization of swine in vivo; Althouse C et al.; Salmonella enterica serovar Typhimurium strain 798 is a clinical isolate from a pig and is known to be able to cause persistent, asymptomatic infections . This strain also is known to exist in two phenotypes (adhesive and nonadhesive to enterocytes) and can switch between the two phenotypes at a rate consistent with phase variation . Cells in the adhesive phenotype are more readily phagocytosed by leukocytes than nonadhesive cells . Once in a leukocyte, adhesive-phase cells survive while nonadhesive-phase cells die . In the present study, nonadhesive mutants were obtained with the transposon TnphoA . A nonadhesive mutant was selected for study and was shown by electron microscopy not to produce fimbriae . The gene encoding the adhesin was cloned and sequenced . Based on its sequence, the adhesin was shown to be FimA, the major subunit of type 1 fimbriae . The nonadhesive mutant was attenuated in its ability to colonize both mouse and pig intestines, but remained capable of systemic spread in mice . The nonadhesive mutant was phagocytosed to the same extent as parental cells in the adhesive phase and then survived intracellularly . These results demonstrated that type 1 fimbriae were important for attachment to enterocytes and promoted intestinal colonization . However, they were not important in promoting phagocytosis or intracellular survival. Infect Immun, 2003 Nov, 71(11), 6320 - 8 Autodisplay: efficacious surface exposure of antigenic UreA fragments from Helicobacter pylori in Salmonella vaccine strains; Rizos K et al.; Live attenuated Salmonella strains expressing antigens of pathogens are promising oral vaccine candidates . There is growing evidence that the topology of expression of the foreign antigens can have a dramatic impact on the immunogenicity . We examined the potential of the AIDA-I (Escherichia coli adhesin involved in diffuse adherence) autotransporter domain to display antigenic fragments of the urease A subunit of Helicobacter pylori for the induction of a protective immune response . In the murine H . pylori model, protection is mainly mediated by CD4(+) T cells, and we therefore used the AIDA-I expression system to successfully express both nearly full-length UreA and defined T-helper-cell epitopes on the surface of an attenuated Salmonella enterica serovar Typhimurium vaccine strain . Surface exposure of the large UreA fragment or of one UreA T-cell epitope mediated a significant reduction in the level of H . pylori in immunized mice after challenge infection, whereas conventional cytoplasmic expression of UreA in Salmonella had no effect . These results support the concept that surface display increases the immunogenicity of recombinant antigens expressed on oral live vaccine carriers and further demonstrate the feasibility of immunizing against H . pylori with Salmonella vaccine strains expressing CD4(+) T-cell epitopes. Infect Immun, 2003 Nov, 71(11), 6132 - 40 Salmonella enterica serovar Typhimurium expressing mutant lipid A with decreased endotoxicity causes maturation of murine dendritic cells; Kalupahana R et al.; A major Salmonella component involved in cellular activation is the lipopolysaccharide (LPS) molecule which can act as a dendritic cell (DC) stimulator . The structure of the lipid A domain of the LPS molecule dictates its immunostimulatory capacity with various cell types . In this study, the role of lipid A as an integral component of Salmonella in stimulating murine DCs was studied by using a Salmonella enterica serovar Typhimurium lpxM mutant with defective lipid A . This study revealed that a mutation in lpxM did not significantly affect the ability of bacteria to activate DCs . Although the lpxM mutant less tumor necrosis factor alpha, interleukin-1beta, and inducible nitric oxide synthase than the parental strain, this was only seen at lower multiplicities of infection (MOIs) . Both strains upregulated surface molecule expression on DCs and augmented the T-cell-stimulating capacity of these cells in an MOI-independent manner . Thus, the lpxM mutation did not appear to affect the stimulatory capacity of the Salmonella mutant. J Food Prot, 2003 Oct, 66(10), 1805 - 10 Recovery of surface bacteria from and surface sanitization of cantaloupes; Barak JD et al.; Practical, effective methods that could be implemented in a food service establishment (restaurant or delicatessen) for the surface sanitization of cantaloupes were microbiologically evaluated . Cantaloupes (Cucumis melo L . var . reticulates) were immersed in an inoculum containing Salmonella enterica serovar Poona or Pantoea agglomerans at ca . 10(4) to 10(5) CFU/ml . An efficient method for the recovery of bacteria from the cantaloupe surface was developed and validated . The method consisted of washing the entire melon with Butterfield's buffer containing 1% Tween 80 in a plastic bag placed inside a plastic pail affixed to an orbital shaker . Levels of S . enterica Poona recovered by washing the entire melon were significantly higher than those recovered by the more common laboratory method of blending the rind . P . agglomerans can be used as a non-pathogenic proxy for S . enterica Poona . A three-compartment surface sanitization method consisting of washing with an antimicrobial soap solution, scrubbing with a brush in tap water, and immersion in 150 ppm of sodium hypochlorite reduced the initial level of recoverable viable bacteria by 99.8% . When examined separately, scrubbing with a vegetable brush in tap water, washing with soap, and dipping in chlorine were found to reduce the bacterial load by 70, 80, and 90%, respectively. J Food Prot, 2003 Oct, 66(10), 1768 - 70 Comparison of sampling methods for the detection of Salmonella on whole broiler carcasses purchased from retail outlets; Simmons M et al.; An experiment was conducted to compare the effectiveness levels of two methods in recovering Salmonella from the same carcass . One hundred fresh whole broiler chickens were purchased from retail outlets over a 5-week period (20 carcasses per week) . After carcasses had been aseptically removed from the packages and giblets had been removed, the carcasses were placed in sterile bags containing 400 ml of 1% buffered peptone water, the bags were shaken for 60 s, and a 30-ml aliquot was removed and incubated for 24 h at 37 degrees C (aliquot sample) . Then, an additional 130 ml of 1% buffered peptone water was immediately added to the bag with the carcass (bringing the volume to 500 ml), the bag was reshaken, and the carcass and rinse were incubated for 24 h at 37 degrees C (whole-carcass enrichment sample) . Following incubation, 0.5-ml samples for the two methods were placed into 10 ml of Rappaport-Vassiliadis broth and into 10 ml of tetrathionate (Hajna) broth and incubated at 42 degrees C for 24 h . Each broth was then streaked onto BG Sulfa agar and modified lysine iron agar and incubated for 24 h at 35 degrees C . Suspected Salmonella colonies were inoculated onto triple sugar iron and lysine iron agar slants and incubated at 35 degrees C for 24 h . Presumptive positive results were confirmed by Poly O and Poly H agglutination tests . Over the 5-week period, 13% of the aliquot samples tested positive for Salmonella, compared with 38% of the whole-carcass enrichment samples from the same carcasses . Recovery rates ranged from 0 of 20 samples to 4 of 20 samples for aliquot method and from 4 of 20 samples to 10 of 20 samples for the whole-carcass enrichment method over the 5-week period . These results indicate that when small numbers of Salmonella are expected, the sampling method has a major influence on the identification of Salmonella-positive carcasses. J Food Prot, 2003 Oct, 66(10), 1762 - 7 Using a portable real-time PCR assay to detect Salmonella in raw milk; Van Kessel JS et al.; The purpose of this study was to determine the efficacy of a portable real-time PCR system in detecting Salmonella spp . in raw milk . The 200 bulk milk samples chosen for this study constituted a subset of the samples for a larger study; this subset contained 24 samples that were culture positive for Salmonella and 176 that were culture negative . Milk was both plated directly on selective agar and plated after enrichment in selective media . Presumptive Salmonella colonies were isolated by direct culturing of five samples, while Salmonella was isolated from the remaining 19 positive samples only after enrichment . Presumptive Salmonella isolates were serotyped, and isolates from 22 samples were confirmed to be Salmonella isolates . PCR assays of culture-positive milk prior to enrichment yielded no evidence of Salmonella . DNA extracts of bacterial pellets from the enriched samples were analyzed for Salmonella by real-time PCR with the Ruggedized Advanced Pathogen Identification Device (RAPID) . Fifty-four samples from the enrichment pellets tested positive for Salmonella by real-time PCR . Two samples that tested positive for Salmonella by culture and serotyping tested Salmonella negative by real-time PCR . Serotyping identified isolates from these samples as Salmonella Montevideo . All DNA extracts of Salmonella Montevideo isolates tested positive for Salmonella by real-time PCR . Thirty-three samples tested negative by culture and positive by real-time PCR . These results indicate that the portable real-time PCR system appears to be a useful tool for detecting Salmonella in raw milk . Additionally, the combination of enrichment and real-time PCR techniques used in this study can yield results in 24 h, compared with the 48 to 72 h required for traditional culture. J Food Prot, 2003 Oct, 66(10), 1756 - 61 Effect of inoculum size, relative humidity, storage temperature, and ripening stage on the attachment of Salmonella Montevideo to tomatoes and tomatillos; Iturriaga MH et al.; The influence of inoculum populations and environmental factors on attachment of Salmonella Montevideo to the surface of tomatoes and tomatillos was evaluated . To study the effect of inoculum size, red, ripe tomatoes were spot-inoculated with bacterial suspensions (10(5) and 10(8) CFU/fruit) and stored at 22 degrees C under 100% relative humidity . The effects of temperature (12, 22, and 30 degrees C) and relative humidity (75, 85, and 97%) on attachment of the pathogen (10(7) CFU/fruit) to tomatoes (red and green) and ripe tomatillos were also evaluated . Inoculated fruits were stored for 90 min at all combinations of temperature and relative humidity, and after rinsing with water, the number of cells attached to the surface was determined . Salmonella Montevideo attached to the surface of tomatoes within 90 min . A direct correlation between the number of attached cells and the population in the inoculum was observed . The percentage of cells that attached immediately after inoculation was approximately 0.3% for the three test products . After storage for 90 min at various temperature and relative humidity conditions, the number of adhering cells ranged from 4.0 to 5.4 log CFU/fruit (1.2% of inoculum) . Both the type of product and the temperature/relative humidity combination had a significant (P < 0.05) effect on attachment of Salmonella Montevideo to the surfaces of tomatoes and tomatillos . Scanning electron micrographs of the cuticles of inoculated washed tomatoes and tomatillos revealed typical skin cell patterns, and only a few randomly dispersed Salmonella Montevideo were observed . Deposition of Salmonella Montevideo on the surface of tomatoes and tomatillos could result in attachment and subsequent colonization under suitable conditions. Mol Immunol, 2003 Nov, 40(7), 463 - 7 Alpha-defensins in the gastrointestinal tract; Cunliffe RN; The human intestinal tract is constantly exposed to an enormous indigenous bacterial flora . It has recently been recognised that antimicrobial peptides of the defensin family likely play a role in protection against microbial invasion at a variety of mucosal epithelial surfaces, including that of the intestinal tract . To date, six alpha-defensins have been identified in humans . Four of these, designated Human Neutrophil Peptides (HNP) 1,2,3 and 4, form part of the armoury of neutrophils, where they participate in systemic innate immunity . The remaining two, Human Defensin (HD) 5 and 6, are expressed in intestinal Paneth cells, and probably contribute to innate defense of the GI mucosal surface . Murine intestinal alpha-defensins (the 'cryptdins') have been extensively studied, but less is known about their human counterparts.The putative mature HD-5 was chemically synthesised and used to raise polyclonal antiserum . Using this anti-HD-5 antiserum, the expression of HD-5 in normal and inflamed intestinal mucosal samples was studied using immunohistochemistry . HD-5 is expressed in Paneth cells and also in some villous epithelial cells in normal duodenum, jejunum and ileum . HD-5 is not expressed in the normal stomach or colon . In cases of gastritis, colonic Crohn's disease and ulcerative colitis, HD-5 is expressed in metaplastic Paneth cells . Utilizing the anti-HD-5 antiserum, native HD-5 was isolated and purified from acid extracts of normal terminal ileal mucosal epithelial cells using cation exchange and reverse phase high pressure liquid chromatography . The purified peptide was characterised using N-terminal amino acid sequence and mass spectral analysis . Antimicrobial activity of the peptide was assessed using a sensitive colony forming unit antimicrobial assay . HD-5 is stored in the predicted precursor form in Paneth cells, and this form does not have antimicrobial activity against a defensin sensitive Salmonella . Potential processing of the precursor form of the HD-5 peptide into a mature active form, was studied by stimulating Paneth cell granule secretion in freshly isolated, cultured ileal crypts . A truncated form of the precursor form of HD-5, but not the predicted mature form, was present in the culture supernatant . Recently published studies suggest that further processing of the molecule occurs in vivo . The expression of HNP 1-3 in the normal intestinal mucosa and in cases of inflammatory bowel disease was studied . In the normal intestinal mucosa, HNP are expressed only in sparse lamina propria neutrophils, and not in Paneth cells . In cases of active ulcerative colitis and Crohn's disease, scattered surface epithelial cells, as well as numerous lamina propria neutrophils, were seen to express HNP . In conclusion, HD-5 is stored only in its precursor form in normal ileal Paneth cells, and partial processing of the peptide to a mature form occurs during and/or after secretion . In inflammatory bowel disease, HD-5 is expressed in metaplastic Paneth cells in the colon, and HNP is expressed by some surface epithelial cells . These studies suggest that antimicrobial defensin peptides may be important in protection of the host against microbial invasion in states of intestinal inflammation. Mutat Res, 2003 Nov 10, 541(1-2), 21 - 9 The Salmonella mutagenicity of industrial, surface and ground water samples of Aligarh region of India; Siddiqui AH et al.; The genotoxicity of three water bodies, viz . industrial waste water of Aligarh city, ground water pumped out from the industrial area of Aligarh, and river water of Yamuna, downstream of Agra, was carried out by means of Ames plate incorporation test and the Ames fluctuation test . All the test samples were significantly mutagenic in both the testing systems . The ground water and river water samples were subjected to XAD concentration prior to the mutagenicity/genotoxicity testing, while the industrial waste water was used directly . Whereas TA98, TA102 and TA104 strains have been found to be maximally sensitive in the Ames plate incorporation assay conducted for various water samples, TA98 and TA100 strains were the most responsive strains in the Ames fluctuation test . The apparent disparity in the sensitivity patterns of various Ames strains by plate incorporation and fluctuation assays could be attributed to a large extent to the different conventional ways of interpretation of the data in these systems. Arch Med Res, 2003 May-Jun, 34(3), 209 - 13 Changing trends in prevalence, morbidity, and lethality in persistent diarrhea of infancy during the last decade in Mexico; Guerra-Godinez JC et al.; BACKGROUND: Persistent diarrhea (PD) of infancy has incurred high morbidity and lethality . However, decrease in its prevalence, morbidity, and lethality appeared to occur progressively throughout the last decade of the twentieth century . Our objective in this study was to compare prevalence, lethality, and morbidity of infants and children with PD managed in a pediatric referral hospital . METHODS: We conducted a comparative cross-sectional study . A total of 546 patients with PD managed during three different periods (1988-1991, 1993-1994, and 1997-1999) were described and analyzed . Prevalence x 100 admissions, prevalence rates of nutritional status, sepsis, pneumatosis intestinalis, carbohydrate and protein intolerance, and lethality were calculated . We used Student t and chi2 tests (alpha = 0.05) . RESULTS: Mean age on admission was 13.8 +/- 24.3 months; 296 (54.2%) patients were males . Prevalence of admissions for PD decreased gradually from 31.7 to 13.8%; rates of lethality and mortality remained unchanged . Malnutrition had high prevalence throughout the three periods evaluated . Rate of carbohydrate intolerance diminished but protein intolerance increased; proportion of pneumatosis intestinalis and bowel perforation did not change . Isolation of Salmonella spp . and small bowel bacterial overgrowth decreased significantly from the 1988-1991 series when compared with later series . CONCLUSIONS: Although these observations were made at a pediatric referral hospital, they may suggest that prevalence of PD is diminishing . However, its lethality and mortality rates remain unchanged . Malnutrition persists as a relevant associated factor . Decrease of carbohydrate intolerance and increase in protein intolerance rates resemble rates of children with PD of developed countries . These observations may reflect an epidemiologic transition of PD in Mexico. Med Parazitol (Mosk), 2003 Jul-Sep, (3), 30 - 1 {Spontaneous infection of ixodes ticks with salmonella}; Nersesov VA et al.; An epizootological study of the ticks gathered from the cattle and ground surface in the Dedoplistskaroisky and Dushetsky districts of Eastern Georgia has identified 5 Salmonella a typhimurium strains . The strains were isolated from the ticks Haemaphysalis punctata, Rhipicephalus bursa, Hyalomma plumbeum . They were found to be resistant to 10 of 16 antibiotics . The strains showed a high sensitivity only to 3 antibiotics, such as gentamicin, cirpofloxacin, and nitrofurantoin and 3 strains were highly sensitive to chloramphenicol . The above ticks seem to have been spontaneously infected with the pathogen Salmonella on the animals at the moment of bacteremia. J Bacteriol, 2003 Nov, 185(21), 6467 - 71 Prophage contribution to bacterial population dynamics; Bossi L et al.; Cocultures of Salmonella strains carrying or lacking specific prophages undergo swift composition changes as a result of phage-mediated killing of sensitive bacteria and lysogenic conversion of survivors . Thus, spontaneous prophage induction in a few lysogenic cells enhances the competitive fitness of the lysogen population as a whole, setting a selection regime that forces maintenance and spread of viral DNA . This is likely to account for the profusion of prophage sequences in bacterial genomes and may contribute to the evolutionary success of certain phylogenetic lineages. J Bacteriol, 2003 Nov, 185(21), 6331 - 9 A new heat shock gene, AgsA, which encodes a small chaperone involved in suppressing protein aggregation in Salmonella enterica serovar typhimurium; Tomoyasu T et al.; We discovered a novel small heat shock protein (sHsp) named AgsA (aggregation-suppressing protein) in the thermally aggregated fraction from a Salmonella enterica serovar Typhimurium dnaK-null strain . The -10 and -35 regions upstream of the transcriptional start site of the agsA gene are characteristic of sigma(32)- and sigma(72)-dependent promoters . AgsA was strongly induced by high temperatures . The similarity between AgsA and the other two sHsps of Salmonella serovar Typhimurium, IbpA and IbpB, is rather low (around 30% amino acid sequence identity) . Phylogenetic analysis suggested that AgsA arose from an ancient gene duplication or amplification at an early evolutionary stage of gram-negative bacteria . Here we show that overproduction of AgsA partially complements the DeltadnaK52 thermosensitive phenotype and reduces the amount of heat-aggregated proteins in both DeltadnaK52 and DeltarpoH mutants of Escherichia coli . These data suggest that AgsA is an effective chaperone capable of preventing aggregation of nonnative proteins and maintaining them in a state competent for refolding in Salmonella serovar Typhimurium at high temperatures. Avian Dis, 2003 Jul-Sep, 47(3), 633 - 9 Effect of prior serial in vivo passage on the frequency of Salmonella enteritidis contamination in eggs from experimentally infected laying hens; Gast RK et al.; Experimental infection models are valuable tools for understanding and preventing the deposition of Salmonella enteritidis inside eggs . Oral inoculation is believed to closely simulate naturally occurring S . enteritidis infections of chickens, but oral infection studies have often generated relatively low frequencies of egg contamination . The present study assessed whether repeated in vivo passage of an S . enteritidis strain could affect its ability to cause egg contamination in experimentally infected hens . The incidence of egg contamination was determined in groups of hens inoculated orally with either a phage type 13a S . enteritidis strain or derivatives of this parent strain that were obtained by three successive rounds of passage and reisolation from tissues of infected hens . Passaged S . enteritidis isolates recovered from ovaries and oviducts induced a significantly higher incidence of egg contamination (16.97%) than was attributed to the parent strain (8.27%) . However, passaged S . enteritidis isolates recovered from livers and spleens were not associated with a significantly increased frequency of deposition in eggs . By either inducing or selecting for the expression of relevant microbial properties, passage of S . enteritidis through reproductive tissues of chickens may be useful for improving the efficiency at which experimental infection models produce egg contamination. Dtsch Tierarztl Wochenschr, 2003 Sep, 110(9), 365 - 8 {Possible interesting dietetic effects of lactulose as a feed additive in pig feed}; Kamphues J et al.; In reared piglets (n = 10), fattening pigs (n = 20) and sows (n = 8) the effects of lactulose as feed additive on the quality and composition of chyme and faeces were tested to find out potential dietetic advantages of its use . The lactulose concentration in the diets varied between 27-29 g/kg dry matter in piglets and fattening pigs and 55-140 g/kg dry matter in the diet of sows . In piglets and fattening pigs the lactulose intake did not alter the dry matter content and pH in faeces; in spite of the higher concentration lactulose did not result in diarrhea in sows or adult minipigs, there was only a slight decrease in the dry matter content of faeces . In contrast to findings in human beings only traces of lactulose reached the hind gut, although higher lactulose concentrations were measured at the end of the small intestine (in piglets: 10-40 g, in fattening pigs 40-70 g lactulose per kg dry matter of chyme) . The oral intake of lactulose did not increase the concentration of lactic acid or volatile fatty acids in the content of the small intestine and did not reduce the pH in the chyme, but in the contents of cecum and colon ascendens higher concentrations of volatile fatty acids were measured (in piglets: significantly higher values, in fattening pigs slightly increased concentrations) . In piglets as well as in fattening pigs lactulose resulted in reduced concentrations of ammonia in the content of small and large intestine, further more the concentrations of lipopolysaccharides were increased in the colonal chyme, when pigs ingested the lactulose containing diet . Due to the fact that only small amounts of lactulose reached the hind gut there are doubts, whether lactulose has comparable dietetic effects in pigs as known from human beings (for example laxative effects, forced elimination of bacteria like salmonella) . The results obtained here in pigs underline the necessity of experimental studies in the target species (including parameters of digestive physiology, chemical/microbial composition of the chyme) before substances are used and recommended for dietetic purposes in feeding practice . In spite of generally adopted similarity of the alimentary tract in pigs and human beings there are eventually some important differences within the intestine, its digestive capacity or in reactions on ingested substances leading to unexpected results. Rev Med Chil, 2003 Aug, 131(8), 837 - 45 {Biochemical phenotypes and phage types of Salmonella enteriditis strains isolated in Antofagasta during the period 1997-2000}; Silva J et al.; BACKGROUND: PhP-S48 (Phene Plate Techniques AB), a method based on biochemical phenotypes has been developed and used successfully to typify S enteritidis strains in epidemiological studies . AIM: To identify phenotypes of S enteritidis isolated from eggs, chicken meat and infected humans in Antofagasta during the period 1997-2000 . MATERIAL AND METHODS: PhP-S48 and phage typing were used to identify phenotypes of 33 S enteritidis strains, sixteen isolated from poultry and 17 from clinical sources . S enteritidis ATCC17036 was used as control strain . RESULTS: Twelve biochemical phenotypes (BTs) including 4 common (C) and 8 single (S) were identified . BTs C1 y C3 containing 16 and 5 strains, respectively, accounted for 63.6% of the isolates . BT C1 was found in poultry and human sources in the period 1997-2000, and BT C3 was isolated from humans, in the period 1999-2000 . Using phage typing, 5 phage types (PT) and 3 strains could be not typed (NTs) . PT1 and PT21 were the dominant phage types, with 14 and 13 strains respectively . Strains of PT1 were isolated from poultry and human sources in the period 1997-2000 . PT21 was found in poultry samples in the period 1997-1998 and in clinical samples, in the period 1997-1998 . Combination of biochemical phenotypes and phage typing divided the strains into 5 phenotypes (BT:PT) . Two phenotypes were the most frequently isolated, phenotype C1:1 with 8 isolates found in eggs and humans in 1999, and phenotype C1:21 with 5 strains isolated in 1997-1999 . CONCLUSIONS: These results indicate the presence of one persistent and one recently emerged phenotype among S enteritidis in Antofagasta, Chile . PhP-S48 also provided information about a relationship among the strains. Bioorg Med Chem, 2003 Nov 3, 11(22), 4785 - 9 Synthesis and biological evaluation of benzo{d}isothiazole, benzothiazole and thiazole Schiff bases; Vicini P et al.; Three new series of benzo{d}isothiazole, benzothiazole and thiazole Schiff bases were synthesized and tested in vitro with the aim of identifying novel lead compounds active against emergent and re-emergent human and cattle infectious diseases (AIDS, hepatitis B and C, tuberculosis, bovine viral diarrhoea) or against drug-resistant cancers (leukaemia, carcinoma, melanoma, MDR tumors) for which no definitive cure or efficacious vaccine is available at present . In particular, these compounds were evaluated in vitro against representatives of different virus classes, such as a HIV-1 (Retrovirus), a HBV (Hepadnavirus) and the single-stranded RNA(+) viruses Yellow fever virus (YFV) and Bovine viral diarrhoea virus (BVDV), both belonging to Flaviviridae . Title compounds were also tested against representatives of Gram-positive and Gram-negative bacteria (Staphylococcus aureus, Salmonella spp.), various atypic mycobacterial strains (Mycobacterium fortuitum and Mycobacterium smegmatis), yeast (Candida albicans) and mould (Aspergillus fumigatus) . None of the compounds showed antiviral or antimicrobial activity . The benzo{d}isothiazole compounds showed a marked cytotoxicity (CC(50)=4-9 microM) against the human CD4(+) lymphocytes (MT-4) that were used to support HIV-1 growth . For this reason, the most cytotoxic compounds of this series were evaluated for their antiproliferative activity against a panel of human cell lines derived from haematological and solid tumors . The results highlighted that all the benzo{d}isothiazole derivatives inhibited the growth of leukaemia cell lines, whereas only one of the above mentioned compounds (1e) showed antiproliferative activity against two solid tumor-derived cell lines. Acta Pol Pharm, 2003 May-Jun, 60(3), 173 - 5 Antimicrobial studies of hydrazone complexes of Hg(II) and Fe(II) divalent metal ions; Donde KJ et al.; The antibacterial, antifungal and antitubercular activities of Hg(II) and Fe(II) complexes of hydrazone were studied . All the complexes have been screened against Staphylococcus aureus, Salmonella typhi, Candida albicans, Aspergillus niger, Saccharomyces cerevisiae and Mycobacterium tuberculosis H37Rv and found to be more toxic than the parent ligand . The activity increased in the order {5-methyl-3-oximino-hexan-2-one-hydrazone}2 Fe(II) < {5-methyl-3-oximino-hexan-2-one-hydrazone}2 Hg(II) < 3-oximino-hexan-2-one-phenylhydrazone}2 Fe(II) < {5-methyl-3-oximino-hexan-2-one-phenylhydrazone}2 Hg(II) for antibacterial and antifungal activity. Environ Mol Mutagen, 2003, 42(3), 192 - 205 Methylated trivalent arsenicals as candidate ultimate genotoxic forms of arsenic: induction of chromosomal mutations but not gene mutations; Kligerman AD et al.; Arsenic is a prevalent human carcinogen whose mutagenicity has not been characterized fully . Exposure to either form of inorganic arsenic, As(III) or As(V), can result in the formation of at least four organic metabolites: monomethylarsonic acid, monomethylarsonous acid (MMA(III)), dimethylarsinic acid, and dimethylarsinous acid (DMA(III)) . The methylated trivalent species, as well as some of the other species, have not been evaluated previously for the induction of chromosome aberrations, sister chromatid exchanges (SCE), or toxicity in cultured human peripheral blood lymphocytes; for mutagenicity in L5178Y/Tk(+/-) mouse lymphoma cells or in the Salmonella reversion assay; or for prophage-induction in Escherichia coli . Here we evaluated the arsenicals in these assays and found that MMA(III) and DMA(III) were the most potent clastogens of the six arsenicals in human lymphocytes and the most potent mutagens of the six arsenicals at the Tk(+/-) locus in mouse lymphoma cells . The dimethylated arsenicals were also spindle poisons, suggesting that they may be ultimate forms of arsenic that induce aneuploidy . Although the arsenicals were potent clastogens, none were potent SCE inducers, similar to clastogens that act via reactive oxygen species . None of the six arsenicals were gene mutagens in Salmonella TA98, TA100, or TA104; and neither MMA(III) nor DMA(III) induced prophage . Our results show that both methylated As(V) compounds were less cytotoxic and genotoxic than As(V), whereas both methylated As(III) compounds were more cytotoxic and genotoxic than As(III) . Our data support the view that MMA(III) and DMA(III) are candidate ultimate genotoxic forms of arsenic and that they are clastogens and not gene mutagens . We suggest that the clastogenicity of the other arsenicals is due to their metabolism by cells to MMA(III) or DMA(III). Environ Mol Mutagen, 2003, 42(3), 185 - 91 Evaluation of mutagenic activity in an extract of pepper tree stem bark (Schinus terebinthifolius Raddi); de Carvalho MC et al.; An extract (decoction) from pepper tree stem bark (Schinus terebinthifolius Raddi) is widely used in Brazil as a topical antiinflammatory agent and to cicatrize wounds . The extract contains catechin, tannins, terpenes, flavonoids, and saponins; of these components, both mutagenic potential and antioxidant properties have been ascribed to flavonoids . The mutagenicity of some flavonoids is believed to be associated with the formation of reactive oxygen species and seems to depend on the number and position of hydroxyl groups . In the present study, we evaluated an extract of S . terebinthifolius in a series of cell-free and bacterial assays in order to determine its genotoxic potential . The extract was negative in a cell-free plasmid DNA test, indicating that it did not directly break DNA . Positive results, however, were obtained in the SOS chromotest, in a forward mutagenesis assay employing CC104 and CC104mutMmutY strains of Escherichia coli, and in the Salmonella reversion assay, using strains TA97, TA98, TA100, and TA102 . All the bacterial tests were performed without exogenous metabolic activation due to the topical use of this preparation . The results indicate that pepper tree stem bark extract produces DNA damage and mutation in bacteria, and that oxidative damage may be responsible for the genotoxicity . FEMS Microbiol Lett, 2003 Sep 26, 226(2), 391 - 6 Proteome analysis of Salmonella enterica serovar Typhimurium fis mutant; Yoon H et al.; Salmonella enterica serovar Typhimurium is an enteric pathogen and a principal cause of gastroenteritis in humans . The factor-for-inversion stimulation protein (Fis) is known to play a pivotal role in the expression of Salmonella pathogenicity island (SPI)-1 genes in addition to various cellular processes such as recombination, replication, and transcription . In order to understand Fis function in pathogenicity of Salmonella, we performed two-dimensional gel electrophoresis and identified proteins whose expression pattern is affected by Fis using mass spectrometry . The results revealed various proteins that can be grouped according to their respective cellular functions . These groups include the genes involved in the metabolism of sugar, flagella synthesis, translation, and SPI expression . Changes in SPI expression suggest the possibility that regulation of genes in SPI-2 as well as SPI-1 is affected by Fis. FEMS Microbiol Lett, 2003 Sep 26, 226(2), 363 - 72 Acidic pH is required for the functional assembly of the type III secretion system encoded by Salmonella pathogenicity island 2; Rappl C et al.; Salmonella enterica employs two type III secretion systems (T3SS) for interactions with host cells during pathogenesis . The T3SS encoded by Salmonella pathogenicity island 2 (SPI2) is required for the intracellular replication of Salmonella and the survival inside phagocytes . During growth in vitro, acidic pH is a signal that promotes secretion of proteins by this T3SS . We analyzed protein levels and subcellular localization of various T3SS subunits under in vitro conditions at acidic or neutral pH, inducing or ablating secretion, respectively . Growth at acidic pH resulted in higher levels of SsaC, a protein forming the outer membrane secretin, without increasing expression of the operon containing ssaC . Acidic pH also induced oligomerization of SsaC subunits, a prerequisite for a functional secretin pore . It has previously been described that environmental stimuli resembling the intraphagosomal habitat of Salmonella control the expression of SPI2 genes . Here we propose that such stimuli also modulate the assembly of a functional T3SS that is capable of translocation of effector proteins into the host cell. FEMS Microbiol Lett, 2003 Sep 26, 226(2), 307 - 14 Transcriptional analysis of the rpoE gene encoding extracytoplasmic stress response sigma factor sigmaE in Salmonella enterica serovar Typhimurium; Miticka H et al.; The rpoE gene of Salmonella enterica serovar Typhimurium (S . Typhimurium), which encodes the extracytoplasmic stress response sigma factor sigmaE, is critically important for the virulence of S . Typhimurium . We analysed expression of rpoE by wild-type and mutant bacteria grown in different conditions by S1-nuclease mapping using RNA, and using in vivo reporter gene fusions . Three promoters, rpoEp1, rpoEp2 and rpoEp3, were located upstream of the S . Typhimurium rpoE gene . The promoters were differentially expressed during growth and under several stress conditions including cold shock . Expression from the rpoEp3 promoter was absent in an S . Typhimurium rpoE mutant, demonstrating its dependence upon sigmaE . The level of mRNA corresponding to rpoEp3 was also higher in a cpxR mutant, indicating a negative regulation of the promoter by the Cpx system . Using this rpoE-dependent promoter, we optimised a two-plasmid system for identification of promoters recognised by S . Typhimurium sigmaE . The rpoEp3 promoter was active in the Escherichia coli two-plasmid system and has an identical transcription start point as in S . Typhimurium but only after induction of S . Typhimurium rpoE expression. Arch Pediatr, 2003 Oct, 10(10), 861 - 8 {Acute gastro-enteritis in children in France: estimates of disease burden through national hospital discharge data}; Fourquet F et al.; OBJECTIVES: To estimate the burden of hospitalized infectious gastroenteritis of children younger than 5 years of age and associated costs . METHODS: We analyzed 1997 hospital discharges with a primary diagnosis of gastroenteritis or a secondary diagnosis of gastroenteritis with gastroenteritis symptoms or complications as primary diagnosis and compared the deaths with those of the national mortality data . RESULTS: Gastroenteritis was associated with 51,125 hospitalizations which accounted for 11.4% of hospitalization discharges for this age group and an annual rate of 1,385 per 100,000 children <5-year-old . Most gastroenteritis (56%) were registered as "probably infectious", 36% as "viral" (43% of which were coded "rotavirus") and 8% as "bacterial" (of which 60% were coded "Salmonella") . The seasonal peak was winter for rotaviral, viral and "probably infectious" gastroenteritis, summer for those related to salmonellosis . Incidence increased inversely with age: 3606/100,000 infants <1-year-old, 257/100,000 4-year-old children . Complications (especially dehydration) were observed in 21% of viral gastroenteritis and 17% of bacterial gastroenteritis . At least, 14 deaths were found in both hospital discharge and mortality data . The mean duration of stay (3.2 days) was significantly higher in infants <1-year-old, viral etiology, association with complications or bronchiolitis . The costs of hospitalization could be estimated to 62 million Euros . DISCUSSION: Our results are similar to those obtained in other developed countries . Despite variations in encoding the discharge reports, data has proven to be effective to describe national trends for this health event . Our study indicates that the public health burden and economic impact of prevention and control measures can be monitored through hospital discharge surveillance. Biotechnol Adv, 1994, 12(4), 703 - 10 Monoclonal antibody technology: applications in veterinary science; Mackie DP; Monoclonal antibodies have revolutionised the study of animals and their diseases . The author looks at the detection of antigen in samples using a range of techniques from indirect fluorescence, through in-situ hybridization to enzyme linked immunosorbent assays . Examples are given of how Salmonella species, mastitis antigens, viral antigens, chlamydial organisms and E . coli toxins can be detected using specific monoclonal antibodies . The recognition of antigen in tissues by monoclonal antibodies is also discussed using as examples; the vitamin biotin, the chicken anemia virus, the growth promoter clenbuterol and the bovine lymphokine, gamma interferon . The ability of monoclonal antibodies to measure specific antibody is also discussed, with particular reference to chicken anemia agent . The review concludes with a discussion of the ability of monoclonal antibody based ELISAs to discriminate between pigs naturally infected with Aujeszky's disease and those vaccinated against the condition. J Vet Diagn Invest, 2003 Sep, 15(5), 438 - 46 Preparation and characterization of polyclonal and monoclonal antibodies against Lawsonia intracellularis; Guedes RM et al.; Proliferative enteropathy is an intestinal infectious disease caused by the obligate intracellular bacterium Lawsonia intracellularis . Immunohistochemistry staining has superior sensitivity over hematoxylin and eosin and silver staining for detecting L . intracellularis in histological sections . A L . intracellularis-specific monoclonal antibody (MAb) produced in the UK (IG4 MAb) has been described in the literature . However, no monoclonal or polyclonal antibodies are commercially available . Therefore, the objective of this study was to produce and characterize new polyclonal and monoclonal antibodies against L . intracellularis that are suitable for diagnostic use . The new monoclonal (2001 MAb) and polyclonal antibodies (1999 PAb) were compared with the IG4 MAb using Western blot analysis of outer membrane proteins (OMPs) of 6 L . intracellularis isolates, Bilophila wadsworthia and Brachyspira hyodysenteriae and using immunohistochemistry of known positive and negative histologic samples and pure cultures of L . intracellularis, B . wadsworthia, B . hyodysenteriae, Salmonella choleraesuis, S . typhimurium, and Escherichia coli K88 . Immunogold staining using 2001 MAb was performed to show the specificity of the antibody against an L . intracellularis surface protein . Western blot analysis showed that the 2001 MAb targeted an OMP of 77 kD, which made it different from the IG4 MAb that targeted an 18-kD OMP . The immunogold stain demonstrated the specificity of the 2001 MAb to a surface protein of L . intracellularis . The polyclonal antibody (1999 PAb) targeted 5 OMPs (77, 69, 54, 42, and 36 kD) . Both the 2001 MAb and 1999 PAb stained known positive, but not negative, histologic samples . Both the 2001 MAb and 1999 PAb reacted with a pure culture of L . intracellularis but not with any other common enteric pathogens . These two new antibodies will be useful for immunodiagnosis of L . intracellularis. J Endovasc Ther, 2003 Aug, 10(4), 843 - 5 Endoprosthetic treatment of a mycotic superficial femoral artery aneurysm; Callaert JR et al.; PURPOSE: To describe the successful stent-graft exclusion of a mycotic aneurysm of the superficial femoral artery . CASE REPORT: A 78-year-old man presented with Salmonella arteritis and the formation of a mycotic false aneurysm of the superficial femoral artery . Antibiotics were administered; the aneurysm was excluded using 2 Hemobahn stent-grafts, and the surrounding hematoma was drained . One year postoperatively, there are no clinical or biochemical signs of infection . Ultrasound examination does not show any fluid around the patent stent-graft . CONCLUSIONS: Stent-graft placement might be an alternative to traditional surgery in selected cases of mycotic aneurysm. J Clin Microbiol, 2003 Oct, 41(10), 4833 - 5 Subtyping of Salmonella enterica serovar typhimurium outbreak strains isolated from humans and animals in Iceland; Gudmundsdottir S et al.; A total of 75 Salmonella enterica serovar Typhimurium strains of various (mainly human and animal) origins were typed by pulsed-field gel electrophoresis (PFGE) and phage typing . These strains were collected during an outbreak in Iceland in 1999 and 2000 . The typing revealed that 84% of the strains belonged to the same PFGE and phage type (PT), namely, PFGE type 1Aa and PT 1. J Clin Microbiol, 2003 Oct, 41(10), 4578 - 82 Association between handling of pet treats and infection with Salmonella enterica serotype newport expressing the AmpC beta-lactamase, CMY-2; Pitout JD et al.; Resistance to the extended-spectrum cephalosporins can occur in Salmonella species via the production of extended-spectrum and AmpC beta-lactamases . We describe human infections with Salmonella enterica serotype Newport phage type 14 strains resistant to ceftazidime (CAZ) and cefoxitin (FOX) related to the handling of pet treats containing dried beef . These strains were isolated from five patients in Calgary, Alberta, Canada, during 2002 and were compared to a strain cultured from a commercial pet treat present at the property of one of the patients . The strains were resistant to FOX, CAZ, cefpodoxime, ampicillin, and chloramphenicol; intermediate resistant to ceftriaxone and cefotaxime; and sensitive to the aminoglycosides, ciprofloxacin, cefepime, and imipenem . Isoelectric focusing, multiplex PCR, and sequencing of the amplicons showed that all strains produced the plasmid-encoded AmpC beta-lactamase, CMY-2 . Restriction analysis of plasmid DNA following transformation demonstrated that bla(CMY-2) was encoded on an approximately 140-kb plasmid . Pulsed-field gel electrophoresis showed the human and pet treat Salmonella strains to be highly related . This study is the first to implicate the transfer of multidrug-resistant Salmonella species through the handling of commercial pet treats containing animal products . In addition to documenting the first cases of human infection caused by CMY-2-producing S . enterica serotype Newport strains in Canada, this study illustrates the necessity of rapid and accurate laboratory-based surveillance in the identification of novel types of antimicrobial resistance. J Clin Microbiol, 2003 Oct, 41(10), 4525 - 30 Etiology of acute diarrhea in adults in southwestern Nigeria; Okeke IN et al.; Stool specimens from 113 adult outpatients with diarrhea in southwestern Nigeria and 63 controls were examined for bacterial and parasitic enteric pathogens . Enterohemorrhagic Escherichia coli (EHEC) (P < 0.02), enteroaggregative E . coli (EAEC) (P < 0.02), and Entamoeba histolytica (P < 0.0002) were significantly associated with diarrhea . Salmonella, Shigella, nontoxigenic Vibrio cholerae, other categories of diarrheagenic E . coli, as well as a variety of helminths were recovered more frequently from the stools of patients than from the stools of controls but did not show a significant association with disease . Multiple pathogens were recovered from 36.3% of specimens, and bloody diarrhea was commonly associated with E . histolytica and diarrheagenic E . coli infections . The majority of EHEC isolates were non-O157 strains that carried the stx(2) gene . Of the 23 EHEC-infected patients, 12 (52.2%) presented during the 10th week of the study . EHEC strains isolated within this cluster were more likely to hybridize with the enterohemolysin gene probe, to be nonmotile and sorbitol positive, and to fail to agglutinate O157 antisera . Pulsed-field gel electrophoresis demonstrated that the only strains with XbaI profiles that occurred more than once were isolated during the 10th and 11th weeks of the study, suggesting an outbreak . The study has demonstrated that E . histolytica, EHEC, and EAEC are important diarrheal pathogens within the study area and that sporadic and epidemic EHEC infections occur in developing as well as developed countries . Routine surveillance for diarrheagenic E . coli, even only at the tertiary-care level, would be useful in identifying outbreaks and assist in identifying environmental reservoirs and transmission routes. Appl Environ Microbiol, 2003 Oct, 69(10), 6099 - 105 Molecular analysis of the rfb O antigen gene cluster of Salmonella enterica serogroup O:6,14 and development of a serogroup-specific PCR assay; Fitzgerald C et al.; The Kauffmann-White scheme for serotyping Salmonella recognizes 46 somatic (O) antigen groups, which together with detection of the flagellar (H) antigens form the basis for serotype identification . Although serotyping has become an invaluable typing method for epidemiological investigations of Salmonella, it does have some practical limitations . We have been characterizing the genes required for O and H antigen biosynthesis with the goal of developing a DNA-based system for the determination of serotype in Salmonella . The majority of the enzymes involved in O antigen biosynthesis are encoded by the rfb gene cluster . We report the sequencing of the rfb region from S . enterica serotype Sundsvall (serogroup O:6,14) . The S . enterica serotype Sundsvall rfb region is 8.4 kb in length and comprises six open reading frames . When compared with other previously characterized rfb regions, the serogroup O:6,14 sequence is most related to serogroup C(1) . On the basis of DNA sequence similarity, we identified two genes from the mannose biosynthetic pathway, two mannosyl transferase genes, the O unit flippase gene and, possibly, the O antigen polymerase . The whole cluster is derived from a low-G+C-content organism . Comparative sequencing of an additional serogroup O:6,14 isolate (S . enterica serotype Carrau) revealed a highly homologous sequence, suggesting that O antigen factors O:24 and O:25 (additional O factors associated with serogroup O:6,14) are encoded outside the rfb gene cluster . We developed a serogroup O:6,14-specific PCR assay based on a region of the putative wzx (O antigen flippase) gene . This provides the basis for a sensitive and specific test for the rapid identification of Salmonella serogroup O:6,14. Cell Microbiol, 2003 Nov, 5(11), 785 - 95 More than just innate immunity: comparative analysis of Chlamydophila pneumoniae and Chlamydia trachomatis effects on host-cell gene regulation; Hess S et al.; Chlamydophila pneumoniae and Chlamydia trachomatis cause infections of the respiratory or urogenital tract . In addition, both species have been associated with atherosclerosis or reactive arthritis respectively . For these intracellular pathogens the interaction with their host-cells is of particular importance . To get insight into this relationship, we conducted a comparative analysis of the host-cell gene regulation of human epithelial cells during infection with Chlamydia . In a screening of HeLa cells by Affymetrix-microchips, numerous regulated host-genes were identified . A detailed expression profile was obtained for 14 genes by real-time RT-PCR - comparing C . pneumoniae, C . trachomatis and intracellular S . typhimurium . The transcriptional responses induced by C . pneumoniae were similar (but usually smaller) compared to C . trachomatis, some were absent . UV-inactivated bacteria induced no differential gene expression suggesting that pathomechanisms other than those associated with innate immunity play here an important role . The expression pattern induced by Salmonella differed substantially . These genus- or group-specific transcriptional response patterns elicited by viable intracellular pathogens may considerably contribute to the different pathologies encountered in the clinic. Planta Med, 2003 Aug, 69(8), 773 - 5 Composition and antibacterial activity of the essential oils from Zanthoxylum rhoifolium; de Abreu Gonzaga W et al.; The essential oils from the aerial parts of leaves, fruits and flowers of Zanthoxylum rhoifolium of Southern Brazil (Rio Grande do Sul), were analysed by GC, GC/MS, and chiral phase gas chromatography (CPGC) . Forty-eight compounds were identified from the essential oils . The major constituents of the essential oil of the leaves were germacrene D (34 %) and bicyclogermacrene (23 %) and of the fruits, menth-2-en-1-ol (46.2 %), beta-myrcene (30.2 %), (-)-linalool (15 %) and (-)-alpha-terpineol (8.45 %) . beta-Myrcene (65 %) and menth-2-en-1-ol (5.4 %) dominate the essential oil of the flowers . The oils of the leaves and fruits were bioactive with antibacterial activity against Staphylococcus aureus (Gram positive), and Klebsiella pneumoniae and Salmonella setubal bacteria (Gram negative) microorganisms, while the essential oil of the flowers was inactive. Int J Food Microbiol, 2003 Nov 1, 87(3), 301 - 6 Efficacy of chlorine and calcinated calcium treatment of alfalfa seeds and sprouts to eliminate Salmonella; Gandhi M et al.; The efficacy of a 20,000 ppm calcium hypochlorite treatment of alfalfa seeds artificially contaminated with Salmonella was studied . Salmonella populations reached >7.0 log on sprouts grown from seeds artificially contaminated with Salmonella and then treated with 20,000 ppm Ca(OCl)(2) . The efficacy of spray application of chlorine (100 ppm) to eliminate Salmonella during germination and growth of alfalfa was assessed . Alfalfa seed artificially contaminated with Salmonella was treated at germination, on day 2 or day 4, or for the duration of the growth period . Spray application of 100 ppm chlorine at germination, day 2, or day 4 of growth was minimally effective resulting in approximately a 0.5-log decrease in population of Salmonella . Treatment on each of the 4 days of growth reduced populations of Salmonella by only 1.5 log . Combined treatment of seeds with 20,000 ppm Ca(OCl)(2) and followed by 100 ppm chlorine or calcinated calcium during germination and sprout growth did not eliminate Salmonella. Int J Food Microbiol, 2003 Nov 15, 88(1), 91 - 5 Detection of Salmonella spp . in tropical seafood by polymerase chain reaction; Sanath Kumar H et al.; The incidence of Salmonella spp . in tropical seafood was studied using standard microbiological techniques and polymerase chain reaction (PCR) . Six of 20 finfish (30%), 4 of 20 clams (20%) and 1 of 20 shrimp (5%) were positive by culture techniques and by PCR . In a comparative study of different selective enrichment broths and selective plating media, more than one enrichment broth and selective agar were found to be necessary for efficient detection of Salmonella from seafood . Selenite cystine broth (SCB) was found to be more efficient compared to tetrathionate broth (TTB) while both bismuth sulfite agar (BSA) and hektoen enteric agar (HEA) were equally effective as selective plating media for fish . In the case of clams, HEA was found to be more effective . The presence of Salmonella spp . could be detected by PCR amplification of DNA extracted directly from the enrichment broths . In two cases, enrichment broths that were positive by PCR did not yield Salmonella by conventional methods. FEBS Lett, 2003 Sep 25, 552(2-3), 110 - 4 Rapidly maturing red fluorescent protein variants with strongly enhanced brightness in bacteria; Sorensen M et al.; A rapidly maturing variant of the red fluorescent protein DsRed was optimized for bacterial expression by random mutagenesis . The brightest variant contains six mutations, two of which (S4T and a silent mutation in codon 2) explain most of the fluorescence enhancement . The novel variants are expressed at 9-60-fold higher levels in Escherichia coli compared to DsRed.T3, but are not superior fluorophores on a per molecule basis . In contrast to previously available DsRed variants, DsRed.T3_S4T is sufficiently bright to monitor Salmonella gene expression in infected animals using flow cytometry . However, no fluorescence enhancement was observed in Leishmania or HeLa cells, indicating that these novel variants are specifically useful for bacteria. Inflammation, 2003 Aug, 27(4), 225 - 31 Differential activation of signal transduction pathways mediating oxidative burst by chicken heterophils in response to stimulation with lipopolysaccharide and lipoteichoic acid; Farnell MB et al.; Toll-like receptors (TLRs) have been previously shown to mediate oxidative burst in chicken heterophils . This study was conducted to begin to map the molecular pathways that regulate TLR-mediated oxidative burst . Peripheral blood heterophils from neonatal chicks were isolated and exposed to known inhibitors of signal transduction pathways for either 20 min (genistein, verapamil, or chelerythrine) or 120 min (pertussis toxin) at 39 degrees C . The cells were then stimulated for 30 min at 39 degrees C with Salmonella enteritidis lipopolysaccharide (LPS) or Staphylococcus aureus lipoteichoic acid (LTA) . The heterophil oxidative burst was then quantitated by luminol-dependent chemiluminescence (LDCL) . Genistein (a tyrosine kinase inhibitor), verapamil (a calcium channel blocker), chelerythrine (a protein kinase C inhibitor), and pertussis toxin (a G-protein inhibitor) significantly reduced LPS-stimulated oxidative burst in chicken heterophils by 34, 50, 63, and 51%, respectively . Although genistein had a statistically significant effect on reducing LPS-stimulated LDCL biologically it seems to play only a minor role within the oxidative burst pathway . Heterophils stimulated with the gram-positive TLR agonist, LTA, activated a different signal transduction pathway since chelerythrine was the only inhibitor that significantly reduced (72%) LTA-stimulated oxidative burst . These findings demonstrate that distinct signal transduction pathways differentially regulate the stimulation of oxidative burst in avian heterophils . Pertussis toxin-sensitive, protein kinase C-dependent, Ca(++)-dependent G proteins appear to regulate oxidative burst of avian heterophils stimulated with gram-negative agonist LPS; whereas, a protein kinase C-dependent signal transduction pathway plays the major role activating the oxidative burst of avian heterophils stimulated with gram-positive agonists . The distinct differences in the response of heterophils to these two agonists illustrate the specificity of TLRs to pathogen-associated molecular patterns (PAMP)s. Berl Munch Tierarztl Wochenschr, 2003 Sep-Oct, 116(9-10), 417 - 20 Serosurvey for antibodies against Salmonella species in free-ranging moose (Alces alces) from Norway; Aschfalk A et al.; An indirect ELISA was developed as a tool for surveillance of antibodies against Salmonella sp . in free-ranging moose (Alces alces) in Norway . Serum samples from 303 clinically healthy moose sampled between 1993-2000 were examined . Anti-Salmonella antibodies were detected in samples from 6 individuals (1.98%) . This is the first evidence of Salmonella-seropositive free-ranging moose . Possible sources and transmission routes of Salmonella comprising environment, wildlife and man are discussed. J Bacteriol, 2003 Oct, 185(20), 6042 - 50 Regulation of expression of the 2-deoxy-D-ribose utilization regulon, deoQKPX, from Salmonella enterica serovar typhimurium; Christensen M et al.; Salmonella enterica, in contrast to Escherichia coli K12, can use 2-deoxy-D-ribose as the sole carbon source . The genetic determinants for this capacity in S . enterica serovar Typhimurium include four genes, of which three, deoK, deoP, and deoX, constitute an operon . The fourth, deoQ, is transcribed in the opposite direction . The deoK gene encodes deoxyribokinase . In silico analyses indicated that deoP encodes a permease and deoQ encodes a regulatory protein of the deoR family . The deoX gene product showed no match to known proteins in the databases . Deletion analyses showed that both a functional deoP gene and a functional deoX gene were required for optimal utilization of deoxyribose . Using gene fusion technology, we observed that deoQ and the deoKPX operon were transcribed from divergent promoters located in the 324-bp intercistronic region between deoQ and deoK . The deoKPX promoter was 10-fold stronger than the deoQ promoter, and expression was negatively regulated by DeoQ as well as by DeoR, the repressor of the deoxynucleoside catabolism operon . Transcription of deoKPX but not of deoQ was regulated by catabolite repression . Primer extension analysis identified the transcriptional start points of both promoters and showed that induction by deoxyribose occurred at the level of transcription initiation . Gel retardation experiments with purified DeoQ illustrated that it binds independently to tandem operator sites within the deoQ and deoK promoter regions with K(d) values of 54 and 2.4 nM, respectively. Can Vet J, 2003 Sep, 44(9), 723 - 8 Antimicrobial susceptibility of hazard analysis critical control point Escherichia coli isolates from federally inspected beef processing plants in Alberta, Saskatchewan, and Ontario; Van Donkersgoed J et al.; A survey to estimate the prevalence of antimicrobial resistance in Escherichia coli was conducted in 7 Canadian federally inspected processing plants during 2001 . Escherichia coli isolates were recovered during routine hazard analysis critical control point sampling from beef carcasses and trim and subsequently tested for their antimicrobial susceptibility by using susceptibility panels . Of the 2653 isolates analyzed, 68% were sensitive to all 18 antimicrobials tested . For 14 of the 18 antimicrobials evaluated, the percentage of resistant isolates was < or = 1 . Twenty-five percent of the isolates were resistant to tetracycline, 9% to sulfamethoxazole, 7% to streptomycin, and 3% to ampicillin . Multiple resistance was found in 12% of the isolates, with 7% showing resistance to 2 antimicrobials, 2% to 3 antimicrobials, 2% to 4 antimicrobials, and 1% to 5 or more antimicrobials . Forty-five different antimicrobial resistance patterns were observed . The reasons for the development of the antimicrobial resistance were not investigated in this study . This study was useful as a pilot to help to develop a national antimicrobial resistance surveillance program in Canada . This study indicates that laboratory standardization is possible for consistent results across the country and that the indicator organism, E . coli, is fairly easy to obtain for surveillance but Salmonella are not, due to their low prevalence in beef. Microbiology, 2003 Oct, 149(Pt 10), 2809 - 17 Activation of hilA expression at low pH requires the signal sensor CpxA, but not the cognate response regulator CpxR, in Salmonella enterica serovar Typhimurium; Nakayama S et al.; A two-component regulatory system, cpxR-cpxA, plays an important role in the pH-dependent regulation of virF, a global activator for virulence determinants including invasion genes, in Shigella sonnei . The authors examined whether the cpxR-cpxA homologues have some function in the expression of Salmonella enterica serovar Typhimurium invasion genes via the regulation of hilA, an activator for these genes . In a Salmonella cpxA mutant, the hilA expression level was reduced to less than 10 % of that in the parent strain at pH 6.0 . This mutant strain also showed undetectable synthesis of an invasion gene product, SipC, at pH 6.0 and reduced cell invasion capacity - as low as 20 % of that of the parent . In this mutant, the reduction in hilA expression was much less marked at pH 8.0 than at pH 6.0 - no less than 50 % of that in the parent, and no significant reduction was observed in either SipC synthesis or cell invasion rate, compared to the parent . Unexpectedly, a Salmonella cpxR mutant strain and the parent showed no apparent difference in all three characteristics described above at either pH . These results indicate that in Salmonella, the sensor kinase CpxA activates hilA, and consequently, invasion genes and cell invasion capacity at pH 6.0 . At pH 8.0, however, CpxA does not seem to have a large role in activation of these factors . Further, the results show that this CpxA-mediated activation does not require its putative cognate response regulator, CpxR . This suggests that CpxA may interact with regulator(s) other than CpxR to achieve activation at low pH. Avian Pathol, 2003 Oct, 32(5), 483 - 8 Association between in vitro heterophil function and the feathering gene in commercial broiler chickens; Swaggerty CL et al.; We recently showed that in vitro heterophil functional efficiency in commercial broiler chickens is genetically controlled and may be a sex-associated trait . To further characterize the genetic mechanism(s) of heterophil functional efficiency, we wanted to determine whether the feathering gene, present on the Z sex chromosome, contributes to heterophil functional efficiency . Heterophils from two pairs of broiler lines were evaluated; each pair contained a fast feather (FF) (lines A and X) and a slow feather (SF) line (lines B and Y) . On days 1 and 4 post-hatch, heterophils isolated from two sets of pure line broilers (A and B, and X and Y) were evaluated for their ability to (1) phagocytize Salmonella enteritidis, and (2) exhibit bactericidal activity against S . enteritidis . On days 1 and 4 post-hatch, heterophils isolated from the FF lines were statistically (P < or = 0.02) more proficient at phagocytizing S . enteritidis than heterophils from SF lines . Bactericidal activity was also statistically (p < or = 0.02) greater on day 1 post-hatch in the heterophils isolated from FF lines compared to heterophils isolated from SF lines . These data indicate that the presence of the FF gene locus on the Z sex chromosome contributes to heterophil function and may contribute to the early innate immune competence of a flock. Vet Immunol Immunopathol, 2003 Nov 15, 96(1-2), 43 - 52 Antibody responses in the serum and gut of chicken lines differing in cecal carriage of Salmonella enteritidis; Berthelot-Herault F et al.; Salmonella frequently causes human foodborne infections . Contaminated products from poultry infected with Salmonella enteritidis are mainly involved . This serovar is able to colonize the gastrointestinal tract and generally produces a chronic asymptomatic carrier state in poultry, except in very young birds . We have developed a model of S . enteritidis carriage in chicks and found that four chicken lines, B13, L2, PA12 and Y11 differ in their cecal colonization by S . enteritidis, whereas their systemic organs are similarly infected . We have monitored the serum and gut antibody responses of these four lines to S . enteritidis for 9 weeks post inoculation (pi) . We confirm that S . enteritidis infected the spleens of the four chicken lines similarly, and that it often colonized the ceca at levels significantly higher in B13 and L2 chicks than those of the PA12 and Y11 chicks . The serum IgM and IgG antibody responses were high and the serum IgA antibody responses low . In contrast, the intestinal secretions contained mostly IgA antibodies . The serum IgM antibody values of the four chicken lines were similar . However, the B13 and L2 chicks often had significantly higher serum IgG and IgA antibody responses than PA12 and Y11 chicks . Only the B13 and L2 chicks showed high, persistent levels of IgA antibody in intestinal secretions . These results suggest that most antibody responses are related to cecal colonization by S . enteritidis . They also indicate that factors other than the antibody levels are involved in the control of this colonization. J Antimicrob Chemother, 2003 Nov, 52(5), 860 - 3 Epub 2003 Sep 30. Antimicrobial susceptibility and genetic relatedness of Salmonella serovars isolated from animal-derived dog treats in the USA; White DG et al.; OBJECTIVES: The objectives of this study were to determine the potential risk of dog treats in transmitting Salmonella to humans in the USA, and to characterize genetic relatedness and antimicrobial resistance among the isolates . METHODS: A total of 158 dog treats derived from pig ears and other animal parts were randomly collected nationwide and assayed for the presence of Salmonella . The Salmonella isolates were characterized using serotyping, pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility testing . RESULTS: Forty-one percent (65/158) of samples were positive for Salmonella . Eighty-four Salmonella isolates, comprising 24 serotypes, were recovered from the 65 positive samples . Fourteen samples were contaminated with more than one Salmonella serotype . PFGE analysis of 78 Salmonella isolates yielded 64 patterns . S . Infantis with PFGE patterns indistinguishable from those of strains identified in Canadian outbreaks in 1999 were recovered in several dog treat products . The majority of Salmonella isolates were susceptible to the antimicrobials tested; however, resistance was observed to tetracycline (26%), streptomycin (23%), sulfamethoxazole (19%), chloramphenicol (8%) and ampicillin (8%) . Twenty-eight (36%) Salmonella isolates were resistant to at least one antimicrobial and 10 (13%) isolates displayed resistance to four or more antimicrobials . Two isolates were identified as S . Typhimurium DT104 with the characteristic penta-resistance phenotype (ampicillin, chloramphenicol, streptomycin, sulfamethoxazole and tetracycline) . One S . Brandenburg isolate was resistant to eight antimicrobials . Seven Salmonella isolates also contained class I integrons encoding resistance genes to aminoglycosides, beta-lactam and streptothricin antimicrobials . CONCLUSIONS: The study indicates that animal-derived dog treats in the USA could be a potential source of animal and human infections with Salmonella, including multidrug-resistant Salmonella strains. EMBO J, 2003 Oct 1, 22(19), 5003 - 14 SseG, a virulence protein that targets Salmonella to the Golgi network; Salcedo SP et al.; Intracellular replication of the bacterial pathogen Salmonella enterica occurs in membrane-bound compartments called Salmonella-containing vacuoles (SCVs) . Maturation of the SCV has been shown to occur by selective interactions with the endocytic pathway . We show here that after invasion of epithelial cells and migration to a perinuclear location, the majority of SCVs become surrounded by membranes of the Golgi network . This process is dependent on the Salmonella pathogenicity island 2 type III secretion system effector SseG . In infected cells, SseG was associated with the SCV and peripheral punctate structures . Only bacterial cells closely associated with the Golgi network were able to multiply; furthermore, mutation of sseG or disruption of the Golgi network inhibited intracellular bacterial growth . When expressed in epithelial cells, SseG co-localized extensively with markers of the trans-Golgi network . We identify a Golgi-targeting domain within SseG, and other regions of the protein that are required for localization of bacteria to the Golgi network . Therefore, replication of Salmonella in epithelial cells is dependent on simultaneous and selective interactions with both endocytic and secretory pathways. J Biol Chem, 2003 Dec 12, 278(50), 50588 - 95 Epub 2003 Sep 26. Signal-dependent requirement for the co-activator protein RcsA in transcription of the RcsB-regulated ugd gene; Mouslim C et al.; The RcsC/YojN/RcsB phosphorelay system controls gene expression in response to a variety of signals, including changes in temperature, osmolarity, and overproduction of membrane proteins . Transcription of certain RcsB-activated genes, such as the capsule synthesis cps operon, requires the co-activator protein RcsA, whereas expression of other RcsB-activated genes is RcsA-independent . We have established previously that a tolB mutation induces transcription of the Salmonella UDP-glucose dehydrogenase ugd gene in an RcsA- and RcsB-dependent manner . This induction is independent of the two-component systems PhoP/PhoQ and PmrA/PmrB, which are required for ugd expression in response to low Mg2+ . We now report that the RcsC/YojN/RcsB system is activated in a pmrA mutant experiencing Fe3+ and low Mg2+, resulting in expression of both cps and ugd genes . However, whereas cps transcription remained RcsA-dependent, ugd transcription became RcsA-independent but dependent on the PhoP protein . S1 mapping experiments demonstrated that RcsA-dependent and -independent transcription of the ugd gene use the same promoter . DNase footprinting analysis identified a PhoP-binding site in the ugd promoter . Yet, PhoP-mediated ugd transcription required either the RcsC/YojN/RcsB or the PmrA/PmrB systems. Indian J Med Sci, 2003 May, 57(5), 199 - 203 Venous thrombosis associated with Salmonella: report of a case and review of literature; Mohanty S et al.; We describe here the first case of Salmonella paratyphi A bacteremia associated with deep vein thrombosis in a 10-year-old patient . In spite of aggressive antibiotic therapy and supportive care, the patient died of progressive respiratory distress and septic shock . Awareness of unusual clinical presentation of Salmonella infection in important . A review of the previously reported cases of Salmonella associated venous thrombosis worldwide is also presented. Cent Eur J Public Health, 2003 Sep, 11(3), 160 - 2 Characterization of Salmonella enterica serotype typhimurium in the Czech Republic: phage types, antimicrobial and plasmid profiles; Karpiskova R et al.; In this study a collection of 547 S . Typhimurium strains isolated in the years 2000 and 2001 both of the human and non-human origin were analysed . 21 different phage types were detected, the most frequent one was DT104 (46%) followed by DT141 (28%) and DT68 (3%) . Resistance to one or more antimicrobial agents was found mainly in DT104 (77.4%) . S . Typhimurium isolates resistant to 5 and more antimicrobial agents were found in three phagetypes DT104 (57%), DT120 and DT155 . Plasmid profiling of DT104 isolates showed 10 different profiles . Pattern A found in 30.5% of tested strains was predominant and carried serovar specific plasmid and one additional small plasmid of approx . 2.5 kb. Eur J Clin Microbiol Infect Dis, 2003 Oct, 22(10), 592 - 6 Epub 2003 Sep 25. Persistent bacteremia in the absence of defined intravascular foci: clinical significance and risk factors; Chowers MY et al.; The clinical significance of and the risk factors for persistent bacteremia were assessed in 299 episodes . Persistent bacteremia was defined as at least two positive blood cultures obtained on different calendar days during the same infectious episode . Short-term bacteremia was defined as positive blood cultures solely on the first day of the infectious episode . A total of 4,277 episodes of bloodstream infections were detected, of which 299 episodes (7%) were persistent bacteremia . The following were independent risk factors were for persistent bacteremia: burns, presence of a central vascular catheter, cirrhosis, infections caused by Salmonella spp., polymicrobial infections, and inappropriate empirical antibiotic treatment . Irrespective of the source of infection, the presence of a central vascular catheter was correlated with an increased risk for persistent bacteremia . Mortality among patients with persistent bacteremia was 50%, compared to 35% among patients with short-term bacteremia . Because of the high mortality associated with persistent bacteremia, a thorough search for the source of infection is essential to ensure timely and appropriate therapy. J Infect Chemother, 2003 Sep, 9(3), 233 - 7 Rapid diagnosis of typhoid fever by PCR assay using one pair of primers from flagellin gene of Salmonella typhi; Massi MN et al.; Using the polymerase chain reaction (PCR) assay, we developed a rapid diagnosis method for Salmonella typhi infection in blood specimens from patients with typhoid fever . Primers were designed from the flagellin gene sequence, which would give an amplification product of 367 base pairs . In this study, the specificity of the assay, with no amplification, was seen for the other Salmonella strains with the flagellin gene, and not for non- Salmonella bacteria . For the sensitivity test, the protocol described allowed the detection of two to three copies of the Salmonella typhi genome, as determined by serial dilution of genomic DNA from Salmonella typhi . With the PCR technique, genomic DNA of Salmonella typhi was detected in 46 of 73 blood samples collected from patients with clinically suspected typhoid fever who had fever within 3 days of admission to the General Hospital, Makassar, South Sulawesi, Indonesia, and who had had no prior antibiotic treatment . The PCR results (63% positive cases) were compared with those of blood culture (13.7% positive cases) and the Widal test (35.6% positive cases), using the same samples from each of the 73 patients admitted to the General Hospital in Makassar . The time taken for PCR analysis of each sample was less than 12 h, compared with 3 to 5 days for blood or clot culture . The PCR with one pair of primers can be used as a novel, rapid diagnostic method for typhoid fever, particularly when results of standard culture assays are negative. Science, 2003 Sep 26, 301(5641), 1918 - 21 Salmonella SipA polymerizes actin by stapling filaments with nonglobular protein arms; Lilic M et al.; Like many bacterial pathogens, Salmonella spp . use a type III secretion system to inject virulence proteins into host cells . The Salmonella invasion protein A (SipA) binds host actin, enhances its polymerization near adherent extracellular bacteria, and contributes to cytoskeletal rearrangements that internalize the pathogen . By combining x-ray crystallography of SipA with electron microscopy and image analysis of SipA-actin filaments, we show that SipA functions as a "molecular staple," in which a globular domain and two nonglobular "arms" mechanically stabilize the filament by tethering actin subunits in opposing strands . Deletion analysis of the tethering arms provides strong support for this model. Immunology, 2003 Oct, 110(2), 206 - 16 A Salmonella typhi OmpC fusion protein expressing the CD154 Trp140-Ser149 amino acid strand binds CD40 and activates a lymphoma B-cell line; Vega MI et al.; CD154 is a type II glycoprotein member of the tumour necrosis factor (TNF) ligand family, which is expressed mainly on the surface of activated T lymphocytes . The interaction with its receptor CD40, plays a central role in the control of several functions of the immune system . Structural models based on the homology of CD154 with TNF and lymphotoxin indicate that binding to CD40 involves three regions surrounding amino acids K143, R203 and Q220, and that strands W140-S149 and S198-A210 are critical for such interactions . Also, it has been reported that two recombinant CD154 fragments, including amino acid residues Y45-L261 or E108-L261 are biologically active, whereas other polypeptides, including S149-L261, are not . Therefore, we decided to construct a fusion protein inserting the W140-S149 amino acid strand (WAEKGYYTMS) in an external loop of the outer membrane protein C (OmpC) from Salmonella enterica serovar Typhi and assess its ability to bind CD40 and activate B cells . The sodium dodecyl sulphate-polyacrylamide gel electrophoresis demonstrated that the chimeric OmpC-gp39 protein conserved its ability to form trimers . Binding to CD40 was established by three variants of enzyme-linked immunosorbent assay, a direct binding assay by coating plates with a recombinant CD40-Fc protein and through two competition assays between OmpC-gp39 and recombinant CD154 or soluble CD40-Fc . Flow cytometry analysis demonstrated that OmpC-gp39 increased the expression levels of major histocompatibility complex II, CD23, and CD80, in Raji human B-cell lymphoma similarly to an antibody against CD40 . These results further support that the CD154/CD40 interaction is similar to the TNF/TNF receptor . This is the first report of a bacterial fusion protein containing a small amino acid strand form a ligand that is able to activate its cognate receptor. Anim Genet, 2003 Oct, 34(5), 339 - 48 Association of twelve candidate gene polymorphisms and response to challenge with Salmonella enteritidis in poultry; Kramer J et al.; Breeding for disease resistance to Salmonella enteritidis (SE) could be an effective approach to control Salmonella in poultry . The candidate gene approach is a useful method to investigate genes that are involved in genetic resistance . In this study, 12 candidate genes that are involved in the pathogenesis of Salmonella infection were investigated using five different genetic groups of meat-type chicken . The genes were natural resistance associated macrophage protein 1 (SLC11A1, previously known as NRAMP1), inhibitor of apoptosis protein 1 (IAP1), prosaposin (PSAP), Caspase-1 (CASP1), inducible nitric oxide production (iNOS), interferon-gamma (IFNG), interleukin-2 (IL2), immunoglobulin light chain (IGL), ZOV3, and transforming growth factors B2, B3 and B4 (TGFB2, B3 and B4) . In total, 117 birds of all groups were challenged with SE at the age of 3 weeks . In all birds at 7-day post-infection SE load in caecum content, spleen and liver were quantified . Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays were used to genotype all animals for each gene . Overall we found the most significant associations with caecum content, nine of 12 genes showed a significant association (SLC11A1, IAP1, PSAP, CASP1, iNOS, IL2, IGL, TGFB2 and TGFB4) . For liver, five genes (SLC11A1, CASP1, IL2, IGL, and TGFB4) and for spleen, only one gene (TGFB3) showed a significant association with SE load . By showing associations of 12 PCR-RFLP assays with SE load after a pathogen challenge, this study confirmed the polygenic nature of disease resistance to SE. APMIS, 2003 Sep, 111(9), 848 - 56 Usefulness of different techniques in the study of the epidemiology of salmonellosis; Ruiz M et al.; Our objective was to evaluate the usefulness of serotyping, phagotyping, antibiotyping and RAPD (random amplified polymorphic DNA) in the study of the epidemiology of salmonellosis in Elche (Spain) . We examined 1232 clinical isolates of non-typhoid Salmonella serotypes . Serotyping adequately differentiates 12.3% of the isolates and phagotyping raises this percentage to 37% . Antibiotyping is a suitable complement in certain circumstances, such as in the case of specific outbreaks . RAPD is a fast and simple technique which is within the reach of most laboratories, complementing the results obtained by antibiotyping and serotyping, in order to be able to control outbreaks of salmonellosis in everyday practice. Afr J Med Med Sci, 2001 Mar-Jun, 30(1-2), 115 - 8 Serological survey of salmonellosis in grey duiker (Sylvicapra grimmia) in Asejire, Irewole Local Government Area, Osun State, Nigeria; Ogunsanmi AO et al.; A serological survey of salmonellosis in grey duiker was carried out in Asejire, Irewole Local Government Area (LGA), Osun State, between August and September, 1996 . The sera of 50 animals were screened for antibodies to salmonella flagella (H) and/or somatic (O) antigens . Ten "bushmeat" hawkers/processors were interviewed on their state of health . Twenty-two (44%) and 3 (6%) had antibodies to the H and O antigens, respectively . Nine (18%) had antibodies to both the H and O antigens . Antibody titres of 1/320 were detected against Salmonella paratyphi serotypes B (12%) and C (2%) and S . typhi serotype D (8%) . Four (40%) of the interviewed hawkers/processors had had 'fever' in the recent past, and 80% of them usually take traditional herbal medicines for most fever-related ailments . A human typhoid epidemiological surveillance carried out within the LGA between 15th March and 4th April, 1995 revealed 64 cases of tentatively diagnosed salmonellosis . Eleven (17.2%) cases were conclusively diagnosed as typhoid fever by laboratory examination . High antibody titres against H and O antigens of S . paratyphi serotype B and S . typhi serotype were detected . Two (3.1%) of the patients died . The public health importance of these findings is discussed. J AOAC Int, 2003 Jul-Aug, 86(4), 775 - 90 Salmonella in foods: new enrichment procedure for TECRA Salmonella Visual Immunoassay using a single rv(R10) only, TT only, or dual rv(R10) and TT selective enrichment broths (AOAC official method 998.09): collaborative study; Hughes D et al.; A collaborative study was conducted to compare a new enrichment procedure for the TECRA Salmonella Visual Immunoassay (TSVIA) with the reference method given in the U.S . Food and Drug Administration's Bacteriological Analytical Manual (7th Ed.) . Three food types (milk powder, pepper, and soy flour) were analyzed in Australia and 3 food types (milk chocolate, dried egg, and raw turkey) were analyzed in the United States . Thirty-eight collaborators participated in the study . The TECRA method was evaluated using both Rappaport-Vassiliadis R10 (RV(R10)) and tetrathionate (TT) broths for selective enrichment . M broth cultures arising from each of the 2 selective enrichment broths were tested in the TSVIA using 2 individual wells, one for each selective broth, and a single well to test the pooled selective enrichment broths . The results for the pooled enrichment broths were reported elsewhere . This study presents the results for the use of single enrichment broths, i.e., RV(R10) only or TT only, with the TSVIA . No significant differences (p > 0.05) were observed for the pairwise comparison of the proportion of positive samples for either RV(R10) or TT used as a single enrichment broth for the TSVIA with that for the reference method. J AOAC Int, 2003 Jul-Aug, 86(4), 714 - 8 Effectiveness of universal pre-enrichment broth for recovery of Salmonella from selected dairy foods; Hammack TS et al.; The relative efficiencies of 2 Bacteriological Analytical Manual (BAM) pre-enrichments, lactose broth (LAC) and brilliant green water (BGW), were compared with Universal Pre-enrichment (UP) broth for the recovery of individual Salmonella serovars from instant nonfat dry milk (NFDM), dry whole milk (DWM), lactic casein (LC), and liquid whole milk (LWM) . BGW was compared with UP broth for the analysis of NFDM and DWM but not with the other 2 matrixes . LAC was compared with UP broth for the analysis of LC and LWM . UP broth was made both from a commercial dehydrated preparation (UPC) and from individual ingredients (UPI) . Bulk quantities of the selected dairy foods were inoculated with Salmonella serovars at levels intended to produce fractionally positive results, where at least half of the test portions analyzed, with one of the methods being evaluated, would be shown to be Salmonella-positive . For NFDM, in 6 of 9 experiments, with 2 different Salmonella serovars, BGW was significantly more productive than either UPI or UPC broth (p < 0.05) . Salmonella was recovered from 118 of 180 test portions with BGW, from 25 of 180 test portions with UPC, and from 14 of 180 test portions with UPI . For DWM, in 2 of 4 experiments, with 2 different Salmonella serovars, BGW was significantly more productive than either UPI or UPC broth (p < 0.05) . Salmonella was recovered from 67 of 80 test portions with BGW, from 36 of 80 test portions with UPC, and from 37 of 80 test portions with UPI . For LWM, in 9 of 9 experiments, with 3 different Salmonella serovars, there were no significant differences among the broths . Salmonella was recovered from 120 of 180 test portions with LAC, from 135 of 180 test portions with UPC, and from 129 of 180 test portions with UPI . For LC, in 5 of 7 experiments, with 2 different Salmonella serovars, both UPI and UPC broth were significantly more productive than LAC (p < 0.05) . Salmonella was recovered from 42 of 140 test portions with LAC, from 114 of 140 test portions with UPC, and from 114 of 140 test portions with UPI . In addition, overall results showed that UPC and UPI broths were equivalent for the recovery of Salmonella from the foods tested, without regard to their performance in comparison with either LAC or BGW. J Pediatr (Rio J), 2003 May-Jun, 79(3), 273 - 6 {Salmonella septicemia associated with interleukin 12 receptor beta1 (IL-12Rbeta1) deficiency}; Carvalho BT et al.; OBJECTIVE: To present a case report of a child who developed sepsis by Salmonella enteritidis associated with the diagnosis of primary immunodeficiency . DESCRIPTION: A twenty-one month old boy presenting fever and skin lesions, bilateral pneumonia with pleural effusion and septic shock . Salmonella enteritidis was isolated in blood cultures and pleural fluid . The identification of the bacteria suggested the presence of the MIM syndrome . The diagnosis of IL-12Rbeta1 was confirmed after IL-12 and IFN-gamma levels were measured using patient cells in a culture medium . The results showed absence of IL-12 and the IFN-gamma post stimulation using BCG . COMMENTS: A severe infection by Salmonella enteritidis is strongly suggestive of an immune system dysfunction . Laboratory tests for humoral, cellular and innate immunity were performed . Interleukin 12 receptor beta1 (IL-12 Rbeta1) deficiency was confirmed after specific laboratory evaluation . The use of INF-gamma is recommended in severe cases. Pediatr Infect Dis J, 2003 Sep, 22(9), 833 - 6 Salmonella retropharyngeal abscess in a child: case report and literature review; Su FH et al.; Retropharyngeal abscess is a rare but serious disease in children . Salmonella species are uncommon causative agents of deep neck infections . We present the clinical course of a 10-year-old boy with a retropharyngeal abscess caused by Salmonella lomita and review 18 previously published cases. Arch Microbiol, 2003 Nov, 180(5), 353 - 61 Epub 2003 Sep 19. PduP is a coenzyme-a-acylating propionaldehyde dehydrogenase associated with the polyhedral bodies involved in B12-dependent 1,2-propanediol degradation by Salmonella enterica serovar Typhimurium LT2; Leal NA et al.; Salmonella enterica forms polyhedral bodies involved in coenzyme-B12-dependent 1,2-propanediol degradation . Prior studies showed that these bodies consist of a proteinaceous shell partly composed of the PduA protein, coenzyme-B12-dependent diol dehydratase, and additional unidentified proteins . In this report, we show that the PduP protein is a polyhedral-body-associated CoA-acylating aldehyde dehydrogenase important for 1,2-propanediol degradation by S . enterica . A PCR-based method was used to construct a precise nonpolar deletion of the gene pduP . The resulting pduP deletion strain grew poorly on 1,2-propanediol minimal medium and expressed 105-fold less propionaldehyde dehydrogenase activity (0.011 micromol min(-1) mg(-1)) than did wild-type S . enterica grown under similar conditions (1.15 micromol min(-1) mg(-1)) . An Escherichia coli strain was constructed for high-level production of His8-PduP, which was purified by nickel-affinity chromatography and shown to have 15.2 micromol min(-1) mg(-1) propionaldehyde dehydrogenase activity . Analysis of assay mixtures by reverse-phase HPLC and mass spectrometry established that propionyl-CoA was the product of the PduP reaction . For subcellular localization, purified His8-PduP was used as antigen for the preparation of polyclonal antiserum . The antiserum obtained was shown to have high specificity for the PduP protein and was used in immunogold electron microscopy studies, which indicated that PduP was associated with the polyhedral bodies involved in 1,2-propanediol degradation . Further evidence for the localization of the PduP enzyme was obtained by showing that propionaldehyde dehydrogenase activity co-purified with the polyhedral bodies . The fact that both Ado-B12-dependent diol dehydratase and propionaldehyde dehydrogenase are associated with the polyhedral bodies is consistent with the proposal that these structures function to minimize propionaldehyde toxicity during the growth of S . enterica on 1,2-propanediol. Int J Med Microbiol, 2003 Aug, 293(4), 261 - 72 Membrane ruffling and invasion of human and avian cell lines is reduced for aflagellate mutants of Salmonella enterica serotype Enteritidis; La Ragione RM et al.; Independent studies have demonstrated that flagella are associated with the invasive process of Salmonella enterica serotypes, and aflagellate derivatives of Salmonella enterica serotype Enteritidis are attenuated in murine and avian models of infection . One widely held view is that the motility afforded by flagella, probably aided by chemotactic responses, mediates the initial interaction between bacterium and host cell . The adherence and invasion properties of two S . Enteritidis wild-type strains and isogenic aflagellate mutants were assessed on HEp-2 and Div-1 cells that are of human and avian epithelial origin, respectively . Both aflagellate derivatives showed a significant reduction of invasion compared with wild type over the three hours of the assays . Complementation of the defective fliC allele recovered partially the wild-type phenotype . Examination of the bacterium-host cell interaction by electron and confocal microscopy approaches showed that wild-type bacteria induced ruffle formation and significant cytoskeletal rearrangements on HEp-2 cells within 5 minutes of contact . The aflagellate derivatives induced fewer ruffles than wild type . Ruffle formation on the Div-1 cell line was less pronounced than for HEp-2 cells for wild-type S . Enteritidis . Collectively, these data support the hypothesis that flagella play an active role in the early events of the invasive process. J Food Prot, 2003 Sep, 66(9), 1704 - 7 Fate of salmonellae in citrus oils and aqueous aroma; Parish ME et al.; The manufacture of orange juice sometimes involves the use of flavor fractions recovered from oranges . The impact of such flavor fractions on Salmonella viability was investigated . A five-strain cocktail of salmonellae was challenged with a singlefold cold-pressed peel oil (CPO), a fivefold CPO, a terpeneless CPO, and an aqueous orange aroma stored at 4 and 25 degrees C . The results obtained in this study indicate that the test compounds possess substantial antimicrobial activity and can cause population reductions larger than the 5-log10 performance standard required by the U.S . Food and Drug Administration's juice hazard analysis critical control point rule (21 CFR 120) . The times required to achieve 5-log10 reductions in Salmonella populations ranged from 0.03 to 42.8 h . In general, levels of antimicrobial activity for the test substances were in the following order: terpeneless CPO > five-fold CPO > single-fold CPO > aqueous aroma. J Food Prot, 2003 Sep, 66(9), 1697 - 700 Effects of different disinfection treatments on the natural microbiota of lettuce; Nascimento MS et al.; In this study, water and eight sanitizing solutions (vinegar at 6, 25, and 50%; acetic acid at 2 and 4%; peracetic acid at 80 ppm, sodium hypochlorite at 200 ppm, and sodium dichloroisocyanurate at 200 ppm) were compared in terms of their effectiveness against the natural microbiota of lettuce . All of the samples were kept in contact with the sanitizing solutions for 15 min, and the effectiveness of a sanitizing agent was evaluated on the basis of the number of decimal reductions of the total aerobic mesophilic count, the mold and yeast count, the total coliform count, and the Escherichia coli count . The average initial levels of these organisms in the samples were 6.94 log10 CFU/g for aerobic mesophilic microorganisms, 5.62 log10 CFU/g for molds and yeasts, and 3.25 log10 CFU/g for total coliforms . Of 10 samples analyzed, only 4 contained E . coli, and the average initial level of this microorganism in these 4 samples was 1.64 log10 CFU/g . Salmonella was not detected in any of the samples tested . The decimal reductions of the populations of aerobic mesophilic microorganisms, molds and yeasts, total coliforms, and E . coli were 0.78, 0.87, 0.82, and >0.14 log10 CFU/g, respectively, in water; 2.89, >3.41, >2.21, and >0.26 log10 CFU/g, respectively, in 50% vinegar; 2.42, >3.20, >1.99, and >0.26 log10 CFU/g, respectively, in 25% vinegar; 1.83, 2.57, 1.58, and >0.26 log10 CFU/g, respectively, in 6% vinegar; 3.91, >3.58, >2.25, and >0.26 log10 CFU/g, respectively, in 4% acetic acid; 3.37, >3.53, >2.25, and >0.26 log10 CFU/g, respectively, in 2% acetic acid; 1.85, 2.32, 1.44, and >0.20 log10 CFU/g, respectively, in 80 ppm of peracetic acid; 2.63, 2.75, 1.91, and >0.26 log10 CFU/g, respectively, in 200 ppm of sodium hypochlorite; and 3.23, >3.08, >1.95, and >0.26 log10 CFU/g, respectively, in 200 ppm of sodium dichloroisocyanurate . Statistical analysis of the results showed that the effectiveness levels for all of the sanitizing agents tested were equivalent to or higher than that for sodium hypochlorite at 200 ppm. J Food Prot, 2003 Sep, 66(9), 1670 - 4 Preenrichment versus direct selective agar plating for the detection of Salmonella Enteritidis in shell eggs; Valentin-Bon IE et al.; The relative effectiveness of two methods for the recovery of Salmonella Enteritidis (SE) from jumbo and medium shell eggs was compared . The first method used in the comparison consisted of a preenrichment of the sample, and the second method was developed by the U.S . Department of Agriculture's Animal and Plant Health Inspection Service (APHIS) . Three bulk lots of blended, pooled eggs, each containing 220 liquid whole eggs that were thoroughly mixed manually were artificially inoculated with different levels of SE cells between approximately 10(0) and 10(3) CFU/ml . Twenty samples containing the contents of approximately 10 eggs each (by weight) were withdrawn from each of the inoculated bulk lots and incubated for 4 days at room temperature (ca . 23 degrees C) . For the APHIS method, each sample was cultured by direct plating onto brilliant green (BG), brilliant green with novobiocin (BGN), xylose lysine desoxycholate (XLD), and xylose lysine agar Tergitol 4 (XLT4) agars . For the preenrichment method, 25-g portions from each pool were enriched in modified tryptic soy broth with 30 mg/liter of FeSO4 . After 24 h of incubation, the preenrichments were subcultured to tetrathionate and Rappaport-Vassiliadis broths, and streaked to BG, BGN, bismuth sulfite, XLD, and XLT4 agar plates . SE isolates were confirmed biochemically and serologically . In all of the experiments, the preenrichment method recovered significantly more SE isolates (P < 0.05) of all the phage types and inoculum levels than did the APHIS method . From a total of 539 jumbo egg test portions analyzed, 381 (71%) were SE-positive by the preenrichment method and 232 (43%) were positive by the APHIS method . From a total of 360 medium egg test portions analyzed, 223 (62%) were SE-positive by the preenrichment method and 174 (48%) were positive by the APHIS method . The preenrichment method provided greater sensitivity for the isolation of SE in contaminated egg slurries than did the APHIS method. J Food Prot, 2003 Sep, 66(9), 1666 - 9 Comparison of homogenization methods for recovering Salmonella Enteritidis from eggs; Seo KH et al.; For Salmonella Enteritidis (SE) detection, shell eggs have been homogenized with stomachers, with electric blenders, and by hand massaging . However, to date, there have been no published reports addressing whether the method of homogenization affects the recovery of SE from raw eggs . Three inoculum levels (10, 126, and 256 SE cells per pool of 10 eggs) were used to conduct three experiments . The 10-egg pools were homogenized by one of four homogenization methods--mechanical stomaching, electric blending, hand massaging, and hand stirring-for 30 s . The homogenized eggs were then incubated at 37 degrees C, and SE colonies were enumerated after 24 and 48 h of incubation . After 24 h of incubation, no SE was recovered from egg samples from stomached or electrically blended pools inoculated with <10 cells, while levels of 106 CFU/ml were found for samples from whipped or hand-massaged pools inoculated with <10 cells . Similarly, after 24 h of incubation, the numbers of SE cells recovered from hand-massaged or hand-stirred egg pools inoculated with 126 cells were significantly larger than the numbers recovered from stomached or electrically blended egg pools inoculated with 126 cells . The number of SE cells recovered from samples homogenized with a blender was still significantly smaller than the numbers recovered from samples homogenized by the other three methods when the inoculum level was increased to 256 CFU per pool . However, the SE count for all samples approached 9 log10 CFU/ml after 48 h of incubation . It is concluded that the detection of small SE populations in shell egg samples could be improved with the use hand massaging and hand stirring for homogenization. J Food Prot, 2003 Sep, 66(9), 1637 - 41 Inactivation of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella in cranberry, lemon, and lime juice concentrates; Nogueira MC et al.; The production of thermally concentrated fruit juices uses temperatures high enough to achieve at least a 5-log reduction of pathogenic bacteria that can occur in raw juice . However, the transportation and storage of concentrates at low temperatures prior to final packaging is a common practice in the juice industry and introduces a potential risk for postconcentration contamination with pathogenic bacteria . The present study was undertaken to evaluate the likelihood of Escherichia coli O157:H7, Listeria monocytogenes and Salmonella surviving in cranberry, lemon, and lime juice concentrates at or above temperatures commonly used for transportation or storage of these concentrates . This study demonstrates that cranberry, lemon, and lime juice concentrates possess intrinsic antimicrobial properties that will eliminate these bacterial pathogens in the event of postconcentration recontamination . Bacterial inactivation was demonstrated under all conditions; at least 5-log Salmonella inactivation was consistently demonstrated at -23 degrees C (-10 degrees F), at least 5-log E . coli O157:H7 inactivation was consistently demonstrated at -11 degrees C (12 degrees F), and at least 5-log L . monocytogenes inactivation was consistently demonstrated at 0 degrees C (32 degrees F). J Food Prot, 2003 Sep, 66(9), 1604 - 10 Antimicrobial performance of alkaline ionic fluid (GC-100X) and its ability to remove Escherichia coli O157:H7 from the surface of tomatoes; Kwon NH et al.; An efficacy test of GC-100X, a noncorrosive alkaline ionic fluid (pH 12) composed of free radicals and supplemented with xylitol, was carried out against six major foodborne pathogens-Staphylococcus aureus FRI 913, Salmonella enterica serovar Enteritidis ATCC 13076, S . enterica serovar Typhimurium DT104 Korean isolate, Vibrio parahaemolyticus ATCC 17803, Escherichia coli O157:H7 ATCC 43894, and Pseudomonas aeruginosa KCTC 1637-at three different temperatures (4, 25, and 36 degrees C) with or without organic load (2% yeast extract) . Results revealed a more than 4-log10 (CFU/ml) reduction (1.0 x 10(4) CFU/ml reduction) against all pathogens reacted at 37 degrees C for 3 h in the absence of organic material . GC-100X solution diluted with an equal volume of distilled or standard hard water (300 ppm CaCO3) showed effective bactericidal activity, particularly against gram-negative bacteria . Washing efficacy of GC-100X solution was compared against E . coli O157:H7 on cherry tomato surfaces with those of a commercially used detergent and chlorine water (100 ppm) . Viable cell counts of E . coli O157:H7 that had penetrated to the cores of tomatoes after sanitizing treatment revealed that GC-100X stock and its 5% diluted solutions had similar washing effects to 100-ppm chlorine water and were more effective than the other kitchen detergent . These results indicate that GC-100X has good bactericidal and sanitizing activities and is useful as a new sanitizer for food safety and kitchen hygiene. J Food Prot, 2003 Sep, 66(9), 1595 - 8 Survival of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella in juice concentrates; Oyarzabal OA et al.; The survival of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella was studied in apple, orange, pineapple, and white grape juice concentrates and banana puree . Pouches of juice concentrate or puree were inoculated with pathogens at a level > or = 10(3) CFU/g and stored at -23 degrees C (-10 degrees F) . Pathogen survival was monitored at 6 and 24 h, once a week for four consecutive weeks, and biweekly thereafter until 12 weeks . When pathogens were not detectable by direct plating, samples were enriched in universal preenrichment broth for 72 h and plated on selective media . Results showed that E . coli O157:H7, L . monocytogenes, and Salmonella were recoverable from all five concentrates through 12 weeks of storage at -23 degrees C. Rev Inst Med Trop Sao Paulo, 2003 Jul-Aug, 45(4), 185 - 91 Epub 2003 Sep 17. Typhoid fever as cellular microbiological model; de Andrade DR et al.; The knowledge about typhoid fever pathogenesis is growing in the last years, mainly about the cellular and molecular phenomena that are responsible by clinical manifestations of this disease . In this article are discussed several recent discoveries, as follows: a) Bacterial type III protein secretion system; b) The five virulence genes of Salmonella spp . that encoding Sips (Salmonella invasion protein) A, B, C, D and E, which are capable of induce apoptosis in macrophages; c) The function of Toll R2 and Toll R4 receptors present in the macrophage surface (discovered in the Drosophila) . The Toll family receptors are critical in the signalizing mediated by LPS in macrophages in association with LBP and CD14; d) The lines of immune defense between intestinal lumen and internal organs; e) The fundamental role of the endothelial cells in the inflammatory deviation from bloodstream into infected tissues by bacteria . In addition to above subjects, the authors comment the correlation between the clinical features of typhoid fever and the cellular and molecular phenomena of this disease, as well as the therapeutic consequences of this knowledge. Cancer Gene Ther, 2003 Oct, 10(10), 737 - 44 Pilot trial of genetically modified, attenuated Salmonella expressing the E . coli cytosine deaminase gene in refractory cancer patients; Nemunaitis J et al.; We performed a pilot trial in refractory cancer patients to investigate the feasibility of intratumoral injection of TAPET-CD, an attenuated Salmonella bacterium expressing the E . coli cytosine deaminase gene . A total of three patients received three dose levels of TAPET-CD (3 x 10(6)-3 x 10(7) CFU/m(2)) via intratumoral injection once every 28 days as long as progression of disease or intolerable toxicity was not observed . From days 4 to 14 of each 28 day cycle, patients also received 5-fluorocytosine (5-FC) at a dose of 100 mg/kg/day p.o . divided three times daily . Six cycles of treatment were administered . No significant adverse events clearly attributable to TAPET-CD were demonstrated . Two patients had intratumor evidence of bacterial colonization with TAPET-CD, which persisted for at least 15 days after initial injection . Conversion of 5-FC to 5-fluorouracil (5-FU) as a result of cytosine deaminase expression was demonstrated in these two patients . The tumor to plasma ratio of 5-FU for these two colonized patients was 3.0, demonstrating significantly increased levels of 5-FU at the site of TAPET-CD colonization and insignificant systemic spread of the bacteria . In contrast, the tumor to plasma ratio of 5-FU of the patient who did not show colonization of TAPET-CD was less than 1.0 . These results support the principle that a Salmonella bacterium can be utilized as a delivery vehicle of the cytosine deaminase gene to malignant tissue and that the delivered gene is functional (i.e . able to convert 5-FC to 5-FU) at doses at or below 3 x 10(7) CFU/m(2). QJM, 2003 Oct, 96(10), 755 - 62 Cerebral infarction in perinatal and childhood bacterial meningitis; Chang CJ et al.; BACKGROUND: Cerebral infarction is an important neurological complication of childhood bacterial meningitis, but little is known about its epidemiology and outcomes . AIM: To determine the predictive factors, clinical features, causative pathogens, and outcomes of cerebral infarction secondary to perinatal and childhood bacterial meningitis . DESIGN: Retrospective analysis METHODS: Over the period 1986-2001, 166 perinatal and childhood patients were identified as having culture-proven bacterial meningitis, of whom 14 had cerebral infarction at admission . The clinical and CSF data of patients with and without cerebral infarctions on admission were compared . RESULTS: Cerebral infarction patients accounted for 10% (14/166) of bacterial meningitis cases, mostly in the first year of life (11/14, 79%) . Salmonella species (n = 4) and Streptococcus pneumoniae (n = 4) were the most frequent causative pathogens, accounting for 57% (8/14) of episodes . Single infarctions were found in four patients and multiple infarctions in 10 . At 1 year follow-up, outcome was good in three, but poor in 11 . Significant differences between the two patient groups at admission included age bands, presence of seizures, hydrocephalus, disturbed consciousness on admission, and CSF lactate concentration . DISCUSSION: There was a high prevalence of cerebral infarctions when the disease was caused by S . pneumoniae and Salmonella species . Occurrence was highest in the first year of life, and the prognosis in this patient group is poor . Risk factors associated with cerebral infarction in our patients included age 28-365 days, seizures, hydrocephalus, disturbed consciousness on admission, and high CSF lactate concentrations. Infect Immun, 2003 Oct, 71(10), 6058 - 62 Differential contribution of Toll-like receptors 4 and 2 to the cytokine response to Salmonella enterica serovar Typhimurium and Staphylococcus aureus in mice; Lembo A et al.; The contribution of murine Toll-like receptors 2 and 4 (TLR2 and -4, respectively) to cytokine induction by heat-killed bacteria was analyzed in vitro and in vivo . Gram-negative bacteria induced cytokines primarily via TLR4; the contribution of TLR2 was only minor . Neither TLR4 nor, surprisingly, TLR2 was required in the MyD88-dependent response to Staphylococcus aureus. Infect Immun, 2003 Oct, 71(10), 6049 - 50 The type IVB pili of Salmonella enterica serovar Typhi bind to the cystic fibrosis transmembrane conductance regulator; Tsui IS et al.; Salmonella enterica serovar Typhi expresses type IVB pili . We show that the prePilS protein (the soluble precursor form of the structural pilin) interacts with a 15-mer peptide representing the first extracellular domain of the cystic fibrosis transmembrane conductance regulator (CFTR), a recognized human epithelial cell receptor for serovar Typhi (G . B . Pier et al., Nature 393:79-82, 1998) . This indicates that after mediating bacterial self-association (C . Morris et al., Infect . Immun . 71:1141-1146, 2003), the pili then act to attach the bacterial clumps to CFTR in the membrane of gut epithelial cells . These sequential type IVB pilus-mediated events cannot be performed by (for example) S . enterica serovar Typhimurium, which may explain why only serovar Typhi causes epidemics of enteric fever in humans. Infect Immun, 2003 Oct, 71(10), 5881 - 91 Intracellular adhesion molecule 1 plays a key role in acquired immunity to salmonellosis; Clare S et al.; This study investigated the role of intracellular adhesion molecule 1 (ICAM-1) during Salmonella enterica serovar Typhimurium infection of mice . We show that ICAM-1 is expressed in and around granulomas on day 4 of infection in wild-type mice . However, when naive ICAM-1(-/-) mice were challenged with a sublethal dose of serovar Typhimurium, there were no detectable differences in systemic bacterial burden over the first 9 days of infection compared to wild-type control mice . When mice were immunized with the S . enterica serovar Typhimurium vaccine strain SL2361 and then challenged with the virulent S . enterica serovar Typhimurium strain C5, 100% of the ICAM-1(-/-) mice succumbed to infection, compared to 30% of wild-type mice . T-cell responses, as measured by activation via interleukin-2 production, as well as antibody responses were comparable in the ICAM-1(-/-) and wild-type mice . Following challenge, counts in organs were significantly higher in the ICAM-1(-/-) mice, and histological examination of organs showed pathological differences . Strain SL3261-immunized wild-type mice had cellular infiltrate and normal granuloma formation in the liver and spleen on days 5 and 10 after challenge with strain C5 . ICAM-1(-/-) mice had a similar infiltrate on day 5, whereas on day 10 the infiltrate was more widespread and there were fewer macrophages associated with the granulomas . High circulating levels of tumor necrosis factor alpha and gamma interferon, as well as a high burden of strain C5 in the blood, accompanied the differences in histopathology . In this study we show that ICAM-1 plays a critical role during rechallenge of immunized mice with virulent S . enterica serovar Typhimurium. J Chromatogr A, 2003 Aug 15, 1009(1-2), 215 - 21 Immunomagnetic separation and detection of Salmonella cells using newly designed carriers; Spanova A et al.; Magnetic nonporous poly(HEMA-co-EDMA) and poly(HEMA-co-GMA) microspheres were prepared by dispersion copolymerisation of 2-hydroxyethyl methacrylate (HEMA) and ethylene dimethacrylate (EDMA) or glycidyl methacrylate (GMA) in the presence of magnetite . They were functionalized by polyclonal Salmonella antibodies via the trichlorotriazine method . Salmonella cells were then successfully identified using cultural and polymerase chain reaction (PCR) methods after their immunomagnetic separation . The PCR sensitivity of target cell detection was negatively influenced by the presence of some compounds used in the process of particle preparation . In some cases, magnetic poly(HEMA-co-EDMA) microspheres with immobilized proteinase K were used for degradation of intracellular inhibitors present in Salmonella cells. J Bacteriol, 2003 Oct, 185(19), 5901 - 5 Global regulation of the Salmonella enterica serovar typhimurium major porin, OmpD; Santiviago CA et al.; The OmpD porin is the most abundant outer membrane protein in Salmonella enterica serovar Typhimurium and represents about 1% of total cell protein . Unlike the case with the less abundant OmpC and OmpF porins, the stoichiometry of OmpD in the outer membrane does not change in response to changes in osmolarity . The abundance of OmpD increases in response to anaerobiosis and decreases in response to low pH, conditions encountered by serovar Typhimurium during the infection of its murine host . By constructing an operon fusion of the lacZY genes with the ompD promoter, we show that the abundance of OmpD in the outer membrane is regulated primarily at the level of transcription and is subject to catabolite repression . In response to anaerobiosis, the abundance of OmpD in the outer membrane also appears to be controlled posttranscriptionally by a function dependent on Fnr. J Appl Toxicol, 2003 Sep-Oct, 23(5), 341 - 8 Toxicological evaluation of an electrically heated cigarette . Part 3: Genotoxicity and cytotoxicity of mainstream smoke; Tewes FJ et al.; The in vitro toxicity of cigarette mainstream smoke from an electrically heated cigarette (EHC) with controlled combustion was compared with that of the standard University of Kentucky Reference Cigarette 1R4F.In the Salmonella reverse mutation assay, strains TA98, TA100, TA102, TA1535 and TA1537 were used in the absence and presence of a metabolic promutagen activation system (S9) to determine the mutagenic potential of the total particulate matter (TPM), which was collected on a glass-fiber filter . In the neutral red uptake assay, mouse embryo BALB/c 3T3 cells were used to determine the cytotoxic potential of TPM as well as of the water-solubles in the gas/vapor phase trapped in phosphate-buffered saline.The TPM from the electrically heated cigarette was up to 90% lower in mutagenicity than that of the 1R4F calculated on an equal TPM basis . This reduction in mutagenicity is consistent with the significantly lower concentration of nearly all constituents analyzed in EHC smoke . With regard to cytotoxicity when calculated on an equal TPM basis, TPM from the electrically heated cigarette was 40% less active relative to the 1R4F . When calculated on a per cigarette basis, the cytotoxicity of both the TPM fraction and the water-solubles in the gas/vapor phase of smoke from the EHC was ca . 80% lower relative to the 1R4F . J Appl Toxicol, 2003 Sep-Oct, 23(5), 323 - 8 Toxicological evaluation of an electrically heated cigarette . Part 1: Overview of technical concepts and summary of findings; Patskan G et al.; This series of papers provides a description of the toxicological evaluation of an electrically heated cigarette (EHC) . With this novel cigarette design the tobacco is heated by a series of electric heating elements, which allows for greater control of the available heat and results in lower temperatures and less combustion compared with conventional lit-end cigarettes . This design was subjected to testing, including an evaluation of smoke chemistry, in vitro bacterial genotoxicity, in vitro mammalian cell cytotoxicity and a 90-day smoke inhalation study in rats . A conventional lit-end cigarette, the University of Kentucky Reference Cigarette 1R4F, was used as a point of comparison in these experiments . When adjusted for the yield of total particulate matter, the EHC delivered 50% lower amounts of about two-thirds of the 69 smoke constituents measured . Mutagenic activity (Salmonella reverse mutation assay) of the particulate phase material in the presence of metabolic activation was ca . 90% lower, with a slight reduction of activity in the absence of metabolic activation . Cytotoxic activity (neutral red assay) of the particulate phase material was ca . 40% lower, with about equal activity of the gas/vapor-phase material . Equal activity was noted between cigarette types in a whole smoke rat inhalation assay . The results from this series of tests demonstrate that the EHC produces a much different smoke--with an at least partially reduced yield of smoke constituents and biological activity--from that of a standard reference cigarette . Pest Manag Sci, 2003 Sep, 59(9), 1007 - 15 Field evaluation of capsaicin as a rodent aversion agent for poultry feed; Jensen PG et al.; Developing additional techniques for reducing animal feed contamination by rodents and controlling rodent populations is critical to efforts aimed at reducing the occurrence of Salmonella spp infection on poultry farms . Capsaicin, a compound found in chili peppers of the genus Capsicum, produces a burning sensation in the mouth of mammals and is used effectively as an animal deterrent for some pest species . Applied to poultry feed, capsaicin may be effective as an aversive agent to deter rodent feeding and enhance acceptability of rodenticide baits . We tested capsaicin-treated poultry diets (2000 and 3000 Scoville Heat Units, SHU) in no-choice feeding trials at four active New York farms in the winter of 1997-1998 . At all farms, consumption of the 2000 SHU diet by rodents (Norway rats, Rattus norvegicus (Berk), and house mice, Mus musculus L) was significantly less than consumption of a control diet . Consumption of the 3000 SHU diet by rodents was significantly less than consumption of a control diet at three of the four farms . Overall, consumption of treated diets was 58-97% and 55-98% less than consumption of the control diet, for the 2000 and 3000 SHU diets, respectively . These reductions appeared to be related closely to the availability of alternative feed sources at these farms . Two-choice feeding trials involving a rodenticide bait (0.05 g kg(-1) brodifacoum) and the 3000 SHU diet demonstrated that Norway rats preferred the rodenticide to the capsaicin-treated poultry feed . Overall, rodenticide bait acceptance was high (95.6%) when offered simultaneously with capsaicin-treated poultry feed . Although poultry managers must utilize several techniques to manage rodent pests, the use of capsaicin-treated diets to reduce feed losses and increase rodenticide bait acceptance appears promising . Use of capsaicin-treated feed on poultry farms may substantially reduce feed contamination by rodents and ultimately the incidence of Salmonella infection in poultry. Pediatr Emerg Care, 2003 Aug, 19(4), 252 - 4 A rare case of Salmonella-mediated sacroiliitis, adjacent subperiosteal abscess, and myositis; Sharieff GQ et al.; We report the case of a 16-year-old female who was ultimately diagnosed with Salmonella sacroiliitis, adjacent subperiosteal abscess, and myositis of the left iliopsoas, gluteus medius, and obturator internus muscles . Early and accurate recognition of this syndrome and other infectious musculoskeletal syndromes can prove difficult for the emergency physician, as these disease processes require special attention to pain of proportion to physical findings and a high index of suspicion. J Antimicrob Chemother, 2003 Oct, 52(4), 715 - 8 Epub 2003 Sep 12. Antimicrobial susceptibility and occurrence of resistance genes among Salmonella enterica serovar Weltevreden from different countries; Aarestrup FM et al.; OBJECTIVES: This study was conducted to investigate the occurrence of antimicrobial resistance among Salmonella Weltevreden isolates from different sources in South-East Asia (Indonesia, Laos, Malaysia, Taiwan, Thailand, Vietnam), Australia, Denmark, New Zealand and the USA . METHODS: A total of 503 isolates were examined for susceptibility to antimicrobial agents, and resistant isolates were examined for the presence of selected resistance genes by PCR . RESULTS: Only 48 (9.5%) of the isolates were resistant to one or more of the antimicrobial agents tested . A low frequency of resistance was found towards ampicillin (1.8%), chloramphenicol (1.6%), florphenicol (0.4%), nalidixic acid (1.6%), neomycin (0.6%), streptomycin (4.4%), sulfamethoxazole (4.2%), tetracycline (4.0%) and trimethoprim (1.4%), whereas all isolates were susceptible to co-amoxiclav, ceftiofur, ciprofloxacin, colistin and gentamicin . All nine ampicillin-resistant isolates contained a sequence similar to the blaTEM-1b gene, one of the eight chloramphenicol-resistant isolates a sequence similar to the catA1 gene, all three neomycin-resistant isolates a sequence similar to the aphA-2 gene, 16 (73%) of the 22 streptomycin-resistant isolates a sequence similar to the aadA gene, the remaining six (27%) a sequence similar to the strA gene, and all 21 sulfamethoxazole-resistant isolates a sequence similar to the sul2 gene . Thirteen (65%) of the 20 tetracycline-resistant isolates contained the tet(A) gene, four (20%) the tet(B) gene, and one (5%) the tet(C) gene . CONCLUSIONS: This study showed a low frequency of resistance among Salmonella Weltevreden isolated from humans and other reservoirs in South-East Asia and elsewhere . There was no major difference in the occurrence of resistance between source or geographical origin. Lett Appl Microbiol, 2003, 37(4), 292 - 8 A comparative heat inactivation study of indigenous microflora in beef with that of Listeria monocytogenes, Salmonella serotypes and Escherichia coli O157:H7; Juneja VK; AIMS: Thermal inactivation of a mixture of five strains of Listeria monocytogenes, four strains of Escherichia coli O157:H7 and eight serotypes of Salmonella were compared with that of indigenous microflora in 75% lean ground beef . METHODS AND RESULTS: Inoculated meat was packaged in bags that were completely immersed in a circulating water bath and held at 55, 57.5 and 60 degrees C for predetermined lengths of time . The surviving cell population was enumerated by spiral plating heat-treated samples onto tryptic soya agar supplemented with 0.6% yeast extract and 1% sodium pyruvate . D-values, determined by linear regression, in beef were 77.49, 21.9, and 10.66 min at 55, 57.5, and 60 degrees C, respectively, for indigenous microflora (z = 5.81 degrees C) . When either of the three pathogens were heated in beef, their D-values calculated were significantly lower (P < 0.05) than those of indigenous microflora at all temperatures . The slope of the thermal death time curve for L . monocytogenes, E . coli O157:H7 and indigenous microflora were similar . Using a survival model for nonlinear survival curves, the D1-values at all temperatures for L . monocytogenes were significantly higher (P < 0.05) compared with those for Salmonella serotypes, E . coli O157:H7 or indigenous microflora . However, higher recovery of a subpopulation of the indigenous microflora in beef exposed to heating at 55, 57.5 or 60 degrees C resulted in significantly higher (P < 0.05) D2-values at all three temperatures, compared with those of the three pathogens at the same test temperatures . CONCLUSIONS: If the thermal process is designed to ensure destruction of indigenous microbial flora, it should also provide an adequate degree of protection against L . monocytogenes, Salmonella serotypes or E . coli O157:H7 . SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study will assist the retail food industry in designing acceptance limits on critical control points that ensure safety, without introducing pathogens in a retail food environment, against L . monocytogenes, E . coli O157:H7 and Salmonella in cooked ground beef. J Appl Microbiol, 2003, 95(4), 773 - 80 Genetic diversity of human isolates of Salmonella enterica serovar Enteritidis in Malaysia; Bakeri SA et al.; AIMS: The study was undertaken to determine clonal relationship and genetic diversity of the human strains of Salmonella enterica serovar Enteritidis isolated from 1995 to 2002 from different parts of Malaysia . METHODS AND RESULTS: Antimicrobial susceptibility test, plasmid profiling and pulsed-field gel electrophoresis were applied to analyse 65 human isolates of S . Enteritidis obtained over an eight year period from different parts of Malaysia . Four nonhuman isolates were included for comparison . A total of 14 distinct XbaI-pulsed-field profiles (PFPs) were observed, although a single PFP X1 was predominant and this particular clone was found to be endemic in Malaysia . The incidence of drug resistant S . Enteritidis remained relatively low with only 37% of the strains analysed being resistant to one or more antimicrobial agents . All except one resistant strain carried at least one plasmid ranging in size from 3.7 to 62 MDa giving nine plasmid profiles . The three isolates from raw milk and one from well-water had similar PFPs to that of the human isolates . CONCLUSIONS: Salmonella Enteritidis strains were more diverse than was previously thought . Fourteen subtypes were noted although one predominant clone persisted in Malaysia . The combination of pulsed-field gel electrophoresis, plasmid profiling and antibiograms provided additional discrimination to the highly clonal strains of S . Enteritidis . SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report to assess the genotypes of the predominant clinical S . Enteritidis in different parts of the country . As S . Enteritidis is highly endemic in Malaysia, the data generated would be useful for tracing the source during outbreaks of gastroenteritis in the study area. Shokuhin Eiseigaku Zasshi, 2003 Jun, 44(3), 155 - 60 A new logistic model for bacterial growth; Fujikawa H et al.; A new logistic model for bacterial growth was developed in this study . The model is based on a logistic model, which is often applied for biological and ecological population kinetics . The new model is described by a differential equation and contains an additional term for suppression of the growth rate during the lag phase, compared with the original logistic equation . The new model successfully described sigmoidal growth curves of Escherichia coli and Salmonella under various initial conditions . Data for E . coli were obtained from our experiments and data for Salmonella from the literature . When the new model was compared with a modified Gompertz model, which is widely used by many predictive microbiology researchers, it proved to be superior to the Gompertz model . Further, Salmonella growth at varying temperature could be well simulated by the new model . These results indicate that the new model will be a useful tool to predict bacterial growth under various temperature profiles. Org Biomol Chem, 2003 Aug 21, 1(16), 2833 - 9 Phosphorylation and dephosphorylation of polyhydroxy compounds by class A bacterial acid phosphatases; Tanaka N et al.; Nonspecific acid phosphatases share a conserved active site with mammalian glucose-6-phosphatases (G6Pase) . In this work we examined the kinetics of the phosphorylation of glucose and dephosphorylation of glucose-6-phosphate (G6P) catalysed by the acid phosphatases from Shigella flexneri (PhoN-Sf) and Salmonella enterica (PhoN-Se) . PhoN-Sf is able to phosphorylate glucose regiospecifically to G6P, glucose-1-phosphate is not formed . The K(m) for glucose using pyrophosphate (PPi) as a phosphate donor is 5.3 mM at pH 6.0 . This value is not significantly affected by pH in the pH region 4-6 . The K(m) value for G6P by contrast is much lower (0.02 mM) . Our experiments show these bacterial acid phosphatases form a good model for G6Pase . We also studied the phosphorylation of inosine to inosine monophosphate (IMP) using PPi as the phosphate donor . PhoN-Sf regiospecifically phosphorylates inosine to inosine-5'-monophosphate whereas PhoN-Se produces both 5'IMP and 3'IMP . The data show that during catalysis an activated phospho-enzyme intermediate is formed that is able to transfer its phosphate group to water, glucose or inosine . A general mechanism is presented of the phosphorylation and dephosphorylation reaction catalysed by the acid phosphatases . Considering the nature of the substrates that are phosphorylated it is likely that this class of enzyme is able to phosphorylate a wide range of hydroxy compounds. Emerg Infect Dis, 2003 Aug, 9(8), 1007 - 9 From pig to pacifier: chitterling-associated yersiniosis outbreak among black infants; Jones TF; In this case-control study of Yersinia enterocolitica infections among black infants, chitterling preparation was significantly associated with illness (p<0.001) . Of 13 samples of chitterlings tested, 2 were positive for Yersinia intermedia and 5 for Salmonella . Decontamination of chitterlings before sale with methods such as irradiation should be strongly considered. Poult Sci, 2003 Sep, 82(9), 1378 - 82 Approach for selection of individual enteric bacteria for competitive exclusion in turkey poults; Bielke LR et al.; The intentional early colonization of the intestinal tract with beneficial microflora, known as competitive exclusion, has been shown to successfully protect poultry from selected enteric pathogens . Although effective cultures have been produced and are available, an inexpensive, air-tolerant, and completely defined culture is needed . Presently, we developed an in vitro competition assay to select for individual facultative anaerobes of poultry enteric origin that could exclude Salmonella . Using this assay, 24 isolates were selected and stored individually . These 24 isolates were amplified in batch culture (tryptic soy broth, 4 h at 40 degrees C) and administered at final dilutions of 10, 100, or 1,000 cfu to day-of-hatch poults . Forty-eight hours later, poults were challenged with 100 to 1,000 cfu antibiotic-resistance-marked Salmonella enteritidis PT 13A by oral gavage . Five days later, all poults were killed, and cecal tonsils were aseptically removed for tetrathionate enrichment (24 h at 37 degrees C) followed by selective plating with marker antibiotics . Selected lactose-negative, antibiotic-resistant colonies typical of Salmonella were further confirmed by serogrouping . Treatment-related protection ranged from 0 to 100% in three experiments . Greatest protection was related to the lowest concentrations of the protective microflora in each experiment . These data suggest that effective combinations of competitive enteric microflora can be identified by appropriate in vitro selection methods. J S Afr Vet Assoc, 2003 Jun, 74(2), 35 - 40 A comparison of selected public health criteria in milk from milk-shops and from a national distributor; O'Ferrall-Berndt MM; Selected public health criteria of pasteurised milk available to the consumer from milk-shops in a pre-defined area of Pretoria compared with a national distributor's milk was evaluated . Of the 135 milk samples purchased from milk-shops, 87% were not fit for human consumption on the basis of the minimum standards prescribed in the Foodstuffs, Cosmetics and Disinfectants Act, 1972 (Act 54 of1972) . The national distributor's milk (n = 79) did not contain any pathogens, toxins nor inhibitory substances and passed all the criteria laid down in the Act . Even though milk-shop milk was sold as having been pasteurised, 38.5% of samples were alkaline phosphatase positive, indicating probable inadequate pasteurisation . Milk-shop milk quality varied between milk-shops and between sampling days and differed significantly (P < 0.05) from the national distributor's milk . Total aerobic plate and coliform counts were generally high for all milk-shop milk samples . Somatic cell counts of milk-shop milk differed significantly (P < 0.05) from the national distributor's milk . Escherichia coli was detected in 1 ml of 17% of milk-shop milk, 95% of which originated from milk which was alkaline phosphatase positive . Salmonella spp . could not be detected in 1 ml in any of the E . coli-positive milk tested . Staphylococcus aureus was isolated from 40% of milk-shop milk samples, and S . aureus enterotoxins from 7.8% of 51 cultures . Inhibitory substances were detected in 54.1% of milk-shop milk . The presence of inhibitory substances and the isolation of E . coli and S . aureus (some of which were able to produce enterotoxins) indicated potentially unsafe milk and poses a serious public health risk to consumers. Zh Mikrobiol Epidemiol Immunobiol, 2003 Jul-Aug, (4), 64 - 7 {New method for the determination of anti-lactoferrin activity of microorganisms}; Valysheva IV et al.; A new method for the determination of the antilactoferrin activity (ALfA) of microorganisms, based on the detection of lactoferrin by the enzyme immunoassay, is proposed . The new method widens the spectrum of microorganisms to be tested, makes it possible to detect lactoferrin inactivation by bacteria producing antagonistically active substances (muramidases, organic acids, hydrogen peroxide, etc.), increases the reliability of the determination of the ALfA antilactoferrin activity of microorganisms due to the increased accuracy of its quantitative characterization . Testing of the culture fluid for lactoferrin following the growth of microorganisms in a medium with this protein revealed the capacity to inactivate lactoferrin in bacteria (Escherichia coli, Salmonella sp.) and yeast-like fungi (Candida sp.), isolated from feces and clinical material, of persons with carrier states, dysbiotic disturbances and pyoinflammatory diseases. Zh Mikrobiol Epidemiol Immunobiol, 2003 Jul-Aug, (4), 59 - 60 {Clinical importance of infective agent persistence in Salmonella infection in children}; Fel'dman SZ et al.; The persistence properties of 70 S . enteriditis cultures and 12 S . typhimurium cultures isolated from the feces of children of the earliest age groups with the gastrointestinal form of Salmonellosis infection were studied . The study revealed that the low level of persistence properties occurred in most cases of mild forms of the disease . Salmonellae with a high level of anticomplement and antilysozyme activity were more often isolated in cases of moderate and severe forms of salmonellosis . The presence of correlation between the expression of the factors under study and the severity of the symptoms of intoxication in combination with the duration of the diarrhea syndrome in moderate and severe forms of Salmonella infection in children of the earliest age groups was established . The suggestion was made that the evaluation of the persistence properties of bacteria may be used for the prognosis of the course of the infectious process. Med Princ Pract, 2003 Oct-Dec, 12(4), 252 - 5 Antimicrobial susceptibility, phage typing and plasmid profile of Salmonella enterica serotype paratyphi A strains isolated in Kuwait; Panigrahi D et al.; OBJECTIVE: To determine the antimicrobial susceptibility, phage type and plasmid profile pattern of Salmonella enterica serotype paratyphi A strains isolated in Kuwait . MATERIAL AND METHODS: From January 1995 to December 1999, 106 strains of S . enterica serotype paratyphi A isolated from an equal number of cases of enteric fever, attending the Infectious Disease and Mubarak Al-Kabeer Hospitals in Kuwait were investigated . The isolates were tested for antimicrobial susceptibility to 8 commonly used antimicrobial agents . Their phage type and plasmid profile patterns were determined using an international set of phages and Qiagen plasmid mini kit, respectively . RESULTS: All of the isolates were susceptible to ciprofloxacin, cefuroxime, ceftazidime, piperacillin and co-trimoxazole . One hundred isolates were susceptible to ampicillin, 99 to chloramphenicol and 98 to tetracycline . None of the isolates was multidrug resistant . Sixty-six percent of the isolates were phage type I, 27.4% phage type II and 6.6% were untypable . All phage type I and untypable strains had 3 plasmids of 2.2, 5 and 20 kb, whereas phage type II strains had only 1 plasmid of 20 kb . CONCLUSION: The findings indicate that while all of the isolates of the S . enterica serotype paratyphi A were susceptible to 4 of the drugs tested, some were resistant to ampicillin, chloramphenicol or tetracycline, thereby indicating the need for continued surveillance and monitoring of antimicrobial susceptibility of these isolates . J Neuroimmunol, 2003 Aug, 141(1-2), 74 - 82 Neuromodulation of enteropathogen internalization in Peyer's patches from porcine jejunum; Green BT et al.; Jejunal Peyer's patches (JPP) are innervated sites of immune induction and enteropathogen infection . We investigated the role of enteric nerves in modulating pathogen entry into porcine JPP . Presumptive norepinephrine (NE)-containing nerve fibers were localized in JPP domes and follicle-associated villi by secondary immunofluorescence histochemistry . NE or the neuronal conduction blocker saxitoxin increased intracellular internalization of pathogenic Salmonella choleraesuis and Escherichia coli O157:H7, but not nonpathogenic E . coli, into isolated JPP mucosa . NE action was prevented by the alpha-adrenergic antagonist phentolamine . Withdrawal of enteric neural activity or NE administration appears to modulate JPP interactions with pathogenic bacteria. J Ethnopharmacol, 2003 Oct, 88(2-3), 253 - 60 Chemical composition, toxicity and mosquito repellency of Ocimum selloi oil; Padilha de Paula J et al.; Ocimum spp . (Lamiaceae) and their essential oils have been traditionally used to kill or repel insects, and also to flavor foods and oral products, in fragrances, in folk medicine and as condiments . In Brazil, Ocimum selloi has been used to treat stomachaches and as an anti-inflammatory remedy . This study was performed to provide data on the chemical composition, acute toxicity, mutagenicity, skin irritant potential and mosquito repellency of Ocimum selloi oil . GC/MS analysis of Ocimum selloi oil revealed that its major constituents were methyl-chavicol or estragole (55.3%), trans-anethole (34.2%), cis-anethole (3.9%) and caryophyllene (2.1%) . Ocimum selloi oil given by gavage to adult Swiss Webster mice produced no adverse effects at doses as high as 1250 mg/kg body weight . Deaths and symptoms (e.g . hypoactivity, ataxia and lethargy) were observed at doses > or =1500 mg/kg body weight, being females apparently more susceptible than males . Genotoxicity of Ocimum selloi oil was evaluated in the Salmonella/microsome assay without and with S9 mixture . The oil, tested up to the toxicity limit (500-700 microg/plate), was not mutagenic to tester strains TA97a, TA98 and TA100 . None of 30 volunteers of either sex exposed to undiluted Ocimum selloi oil (4-h patch test) showed a positive skin irritant reaction . A field test (six volunteers, each individual his/her own control) was carried out to evaluate mosquito (Anopheles braziliensis) repellency of Ocimum selloi oil diluted in ethanol (10% v/v) . The median number of mosquito bites on volunteers' skin-recorded for 30 min after application of Ocimum selloi oil (2, range 0-3) was much lower than that noted after application of the solvent alone (19.5, 3-25) (Wilcoxon test, P<0.01) . In conclusion, results showed that Ocimum selloi oil is an effective mosquito repellent that presents a low acute toxicity, poses no mutagenic risk and seems not to be irritating to human skin. J Membr Biol, 2003 Jun 1, 193(3), 137 - 52 Phagosome maturation: a few bugs in the system; Scott CC et al.; Cells of the innate immune system ingest and destroy invading microorganisms by initially engulfing them into a specialized vacuole, known as the phagosome . The membrane of the forming phagosome is similar to the plasmalemma and its contents resemble the extracellular milieu . As such, the nascent phagosome is not competent to kill and eliminate the ingested microorganisms . However, shortly after sealing, the phagosome undergoes a series of rapid and extensive changes in its composition, the result of a sophisticated sequence of membrane fusion and fission reactions . Understanding the molecular basis of these events is of particular importance, since they are often the target of disruption by intracellular parasites such as Mycobacterium, Salmonella and Legionella . The objective of this review is to summarize the current knowledge of the molecular mechanisms underlying phagosomal maturation and its subversion by parasitic microorganisms. Proc Natl Acad Sci U S A, 2003 Sep 16, 100(19), 10913 - 8 Epub 2003 Sep 05. The response of natural killer T cells to glycolipid antigens is characterized by surface receptor down-modulation and expansion; Wilson MT et al.; CD1d-restricted natural killer T (NKT) cells are a subset of regulatory T cells that react with glycolipid antigens . Although preclinical studies have effectively targeted NKT cells for immunotherapy, little is known regarding the early in vivo response of these cells to antigenic stimulation . We have analyzed the early response of NKT cells to glycolipid antigens and bacterial infection by using specific reagents for tracking these cells . Our results demonstrate dramatic in vivo expansion and surface phenotype alterations after NKT cell activation with alpha-galactosylceramide . In addition, we show significant NK1.1 down-modulation on NKT cells in the setting of oral Salmonella infection . Our results indicate that in vivo activation of NKT cells leads to a dynamic response characterized by surface receptor down-modulation and expansion . These findings alter current understanding of NKT cell biology and should aid in the rational design of NKT cell-based immunotherapies. Environ Toxicol Chem, 2003 Sep, 22(9), 1945 - 55 The use of toxicity bioassays to monitor the recovery of oiled wetland sediments; Mueller DC et al.; Six toxicity assays were compared to determine their efficacy in assessing toxicity dynamics during a wetland bioremediation study . The toxicity bioassays used were the Microtox 100% elutriate test, Microtox Solid Phase Test (SPT), amphipod assay, P450 reporter gene system, Toxi-ChromoPad test and a Salmonella/microsome assay . Oiled sediments were analyzed for toxicity in the petroleum biostimulation experiment conducted along the San Jacinto River, near Houston (TX, USA) . The bioassays were evaluated for their ability to measure acute toxicity, chronic toxicity, and the mutagenic potential of amended oiled plots as compared to oiled and unoiled control plots . Amendments were diammonium phosphate alone or in combination with potassium nitrate, which served as an alternate electron acceptor . With exception of the Toxi-ChromoPad and Salmonella tests, the bioassays exhibited a significant increase in toxicity after oil application . Microtox bioassays detected significant sediment toxicity up to 29 d after oil and amendment application . The Microtox solid phase test results correlated strongly with gas chromatography-mass spectrometry analyses of total target saturate and aromatic hydrocarbons . The amphipod assay detected initial toxicity with a decline to day 70, followed by a significant increase in toxicity on day 140 in plots receiving nutrient amendments, which may be in response to excessive nutrient application . Low levels of enzyme induction were observed with the P450 reporter gene system assay in all oiled sediments throughout the study, suggesting low but persistent levels of polycyclic aromatic hydrocarbons . Of the six tests, the two Microtox tests and the amphipod test showed the most potential in evaluating petroleum toxicity in wetland sediments. J Clin Microbiol, 2003 Sep, 41(9), 4462 - 4 In vivo development of quinolone resistance in Salmonella enterica serotype typhimurium DT104; Kristiansen MA et al.; Salmonella enterica serotype Typhimurium definitive phage type 104 was isolated several times from the same patient over a period of 2 years . The strain developed reduced sensitivity to fluoroquinolones, and a mutation in the gyrA gene that is associated with reduced sensitivity to quinolones was identified. J Clin Microbiol, 2003 Sep, 41(9), 4388 - 94 Molecular typing of Salmonella enterica serovar typhi isolates from various countries in Asia by a multiplex PCR assay on variable-number tandem repeats; Liu Y et al.; A multiplex PCR method incorporating primers flanking three variable-number tandem repeat (VNTR) loci (arbitrarily labeled TR1, TR2, and TR3) in the CT18 strain of Salmonella enterica serovar Typhi has been developed for molecular typing of S . enterica serovar Typhi clinical isolates from several Asian countries, including Singapore, Indonesia, India, Bangladesh, Malaysia, and Nepal . We have demonstrated that the multiplex PCR could be performed on crude cell lysates and that the VNTR banding profiles produced could be easily analyzed by visual inspection after conventional agarose gel electrophoresis . The assay was highly discriminative in identifying 49 distinct VNTR profiles among 59 individual isolates . A high level of VNTR profile heterogeneity was observed in isolates from within the same country and among countries . These VNTR profiles remained stable after the strains were passaged extensively under routine laboratory culture conditions . In contrast to the S . enterica serovar Typhi isolates, an absence of TR3 amplicons and a lack of length polymorphisms in TR1 and TR2 amplicons were observed for other S . enterica serovars, such as Salmonella enterica serovar Typhimurium, Salmonella enterica serovar Enteritidis, and Salmonella enterica serovar Paratyphi A, B, and C . DNA sequencing of the amplified VNTR regions substantiated these results, suggesting the high stability of the multiplex PCR assay . The multiplex-PCR-based VNTR profiling developed in this study provides a simple, rapid, reproducible, and high-resolution molecular tool for the epidemiological analysis of S . enterica serovar Typhi strains. J Clin Microbiol, 2003 Sep, 41(9), 4292 - 7 Discrimination of d-tartrate-fermenting and -nonfermenting Salmonella enterica subsp . enterica isolates by genotypic and phenotypic methods; Malorny B et al.; A multiplex PCR and an improved lead acetate test were developed to discriminate d-tartrate-fermenting and -nonfermenting Salmonella enterica subsp . enterica strains . Both methods showed an accuracy of 100% when 125 Salmonella strains belonging to 15 serovars were tested . Special emphasis was given to S . enterica subsp . enterica serovar Paratyphi B isolates because of the clinical importance of its d-tartrate-nonfermenting variant and the recently increasing numbers of cases of human outbreaks caused by its fermenting variant (formerly Salmonella serovar Java) . The lead acetate test described previously (G . A . Alfredsson, R . M . Barker, D . C . Old, and J . P . Duguid, J . Hyg . 70:651-666, 1972) was modified in the inoculation and incubation procedure . The PCR assay was based on the genotypic difference of the presence (d-tartrate-fermenting strains) or absence (d-tartrate-nonfermenting strains) of the ATG start codon for the gene STM 3356, which encodes a putative cation transporter . Sequence data revealed a nucleotide exchange from G to A within the ATG start codon of gene STM 3356 in the d-tartrate-nonfermenting strains . In order to increase the reliability of the PCR assay, a positive control based on a Salmonella genus-specific primer set for the detection of Salmonella DNA was included . The PCR-based discrimination needs only several hours compared to 6 days needed by the improved lead acetate test to obtain reliable results . Consequently, the PCR d-tartrate assay should be the method of choice for the discrimination of d-tartrate-fermenting and -nonfermenting Salmonella strains in the future. J Clin Microbiol, 2003 Sep, 41(9), 4279 - 84 Phage-based typing scheme for Salmonella enterica serovar Heidelberg, a causative agent of food poisonings in Canada; Demczuk W et al.; Salmonella enterica serovar Heidelberg is perhaps the second most frequent Salmonella serovar isolated from humans and the most common isolated from animals in Canada . This pathogen has shown increasing resistance to antimicrobial agents and mimics the multidrug resistance observed in S . enterica serovar Typhimurium strain DT 104 . However, unlike for serovar Typhimurium, a rapid and inexpensive subtyping method has not been available for large-scale surveillance efforts . We developed a phage typing scheme and subtyped 2,523 strains of serovar Heidelberg from outbreaks, sporadic infections, and environmental sources in Canada between January 1991 and December 2000 . All strains were sensitive to one or more phages and could be subdivided into 49 phage types . A total of 196 isolates from 13 major outbreaks could be subtyped into six phage types, while 86 strains from family outbreaks were assigned to seven phage types . All strains were typeable, and epidemiologically related strains isolated from patients and implicated foods had identical phage types, antibiograms, and pulsed-field gel electrophoresis (PFGE) patterns . Combining PFGE with phage typing increased the discriminatory power of the analysis beyond that of either method alone . We concluded that this phage typing scheme, in conjunction with PFGE, enhances subtyping of serovar Heidelberg strains . Furthermore, this phage typing scheme is a rapid, economical, stable, and reliable epidemiologic tool for tracing the origin of food-borne disease and for the surveillance of sporadic infections. J Clin Microbiol, 2003 Sep, 41(9), 4270 - 8 Molecular properties of Salmonella enterica serotype paratyphi B distinguish between its systemic and its enteric pathovars; Prager R et al.; Salmonella enterica serotype O1,4,5,12:Hb:1,2, designated according to the current Kauffmann-White scheme as S . enterica serotype Paratyphi B, is a very diverse serotype with respect to its clinical and microbiological properties . PCR and blot techniques, which identify the presence, polymorphism, and expression of various effector protein genes, help to distinguish between strains with systemic and enteric outcomes of disease . All serotype Paratyphi B strains from systemic infections have been found to be somewhat genetically related with respect to the pattern of their virulence genes sopB, sopD, sopE1, avrA, and sptP as well as other molecular properties (multilocus enzyme electrophoresis type, pulsed-field gel electrophoresis {PFGE} type, ribotype, and IS200 type) . They have been classified as members of the systemic pathovar (SPV) . All these SPV strains possess a new sopE1-carrying bacteriophage (designated PhiSopE309) with high SopE1 protein expression but lack the commonly occurring avrA determinant . They exhibit normal SopB protein expression but lack SopD protein production . In contrast, strains from enteric infections classified as belonging to the enteric pathovar possess various combinations of the respective virulence genes, PFGE pattern, and ribotypes . We propose that the PCR technique for testing for the presence of the virulence genes sopE1 and avrA be used as a diagnostic tool for identifying both pathovars of S . enterica serotype Paratyphi B . This will be of great public health importance, since strains of serotype Paratyphi B have recently reemerged worldwide. Appl Environ Microbiol, 2003 Sep, 69(9), 5138 - 56 Predictive thermal inactivation model for effects of temperature, sodium lactate, NaCl, and sodium pyrophosphate on Salmonella serotypes in ground beef; Juneja VK et al.; Analyses of survival data of a mixture of Salmonella spp . at fixed temperatures between 55 degrees C (131 degrees F) and 71.1 degrees C (160 degrees F) in ground beef matrices containing concentrations of salt between 0 and 4.5%, concentrations of sodium pyrophosphate (SPP) between 0 and 0.5%, and concentrations of sodium lactate (NaL) between 0 and 4.5% indicated that heat resistance of Salmonella increases with increasing levels of SPP and salt, except that, for salt, for larger lethalities close to 6.5, the effect of salt was evident only at low temperatures (<64 degrees C) . NaL did not seem to affect the heat resistance of Salmonella as much as the effects induced by the other variables studied . An omnibus model for predicting the lethality for given times and temperatures for ground beef matrices within the range studied was developed that reflects the convex survival curves that were observed . However, the standard errors of the predicted lethalities from this models are large, so consequently, a model, specific for predicting the times needed to obtained a lethality of 6.5 log(10), was developed, using estimated results of times derived from the individual survival curves . For the latter model, the coefficient of variation (CV) of predicted times range from about 6 to 25% . For example, at 60 degrees C, when increasing the concentration of salt from 0 to 4.5%, and assuming that the concentration of SPP is 0%, the time to reach a 6.5-log(10) relative reduction is predicted to increase from 20 min (CV = 11%) to 48 min (CV = 15%), a 2.4 factor (CV = 19%) . At 71.1 degrees C (160 degrees F) the model predicts that more than 0.5 min is needed to achieve a 6.5-log(10) relative reduction. Niger J Med, 2003 Jan-Mar, 12(1), 22 - 6 Cellular immunity and diarrhoeal disease amongst patients infected with the human immunodeficiency viruses 1 and 2 in Zaria, Nigeria; Keshinro IB et al.; This study was carried out to determine the aetiological agents associated with diarrhoea in Nigerians infected with the Human Immunodeficiency Viruses, and to correlate the cellular immunity status with the causes of diarrhoea . The mean duration of diarrhoea was 20.7 weeks . Giardia lamblia was the commonest pathogen and was isolated from the stools of 10 patients (25%) . Isospora belli was isolated in 3 of the patients (7.5%) but in none of the controls . Other pathogens isolated include salmonella spp . (12.5%), Entamoeba histolytica (7.5%), hookworm (5%), and shigella spp . (5%) . No pathogens were identified in seventeen cases (42.5%) . No statistically significant difference was established in the stool microbiological findings of the cases and controls . No statistically significant relationship was established between stool microbiological findings and cellular immunity in the patients (ANOVA P > 0.05) . It was concluded that the organisms associated with diarrhoea in the HIV-infected patient are similar to those found in HIV-seronegative patients with diarrhoea, and that there is no correlation between the degree of immunodeficiency and the aetiology of diarrhoea. Orthopade, 2003 Aug, 32(8), 744 - 50 {In vitro toxicity and mutagenicity of CoCrMo and TiAl wear particles}; Katzer A et al.; Contact of wear particles with body fluids can result in widespread dissemination of extractable constituents from joint implants . The aim of this in vitro study is to clarify whether there is a mutagenic and/or carcinogenic risk from Co(28)Cr(6)Mo and Ti(6)Al(4)V wear particles . Particles of a representative size were produced by fretting; toxicity and mutagenicity were investigated using the Ames Salmonella/microsome test and the V79-HGPRT Test (Chinese hamster fibroblasts) . To obtain the greatest possible elution of all constituents, the metallic wear particles were extracted with DMSO and water and the resulting eluates mixed together . After repeated test series under standardized conditions, neither the bacterial nor the mammalian cell assays produced evidence of toxic or mutagenic effects in the concentration range under study . It is therefore not to be expected that CoCrMo or TiAl alloys initiate carcinogenesis in the human organism. Scand J Infect Dis, 2003, 35(6-7), 416 - 8 Adjacent organ involvement in Salmonella aortic aneurysms; Habib AG; Salmonella aortic aneurysms occasionally affect adjoining organs . This study reports on 2 elderly men with fatal cases of Salmonella enteritidis involving adjacent organs: aortobronchial fistula from a thoracic aneurysm, and renal involvement from an infrarenal aneurysm . The hope of averting a tragic outcome lies in prompt clinical and radiological recognition followed by effective medical and early surgical interventions. Eur J Epidemiol, 2003, 18(7), 699 - 702 Outbreaks of food borne diseases in the Lazio region, Italy: the results of epidemiological field investigations; Faustini A et al.; BACKGROUND: More thorough information about risks, exposures and vehicles of food borne diseases can be obtained from epidemiological field investigations than from infectious disease reports or laboratory data . METHODS: We analysed the results of 410 field investigations of food borne disease outbreaks reported from 1996 to 2000 and conducted as cohort studies . RESULTS: The incidence of food borne outbreaks increased from 0.8/100,000 in 1996 to 2.0 in 1999, as did the incidence of salmonellosis (from 16/100,000 to 21 in the same period) and diarrhoea episodes reported by laboratories (from 12/100,000 in 1997 to 29 in 1999) . Of the food borne disease outbreaks, 264 (64.4%) occurred in private homes; 5 (1.2%) in hospitals; 31 (7.6%) in canteens and refectories, 84 (20.5%) in restaurants, 41 of which occurred during special functions . The home outbreaks exposed few people (average of 7), had high attack rates (61.7% average) and a high proportion of known aetiology (66%), while food borne disease outbreaks in canteens and restaurants (during special functions) exposed many people (300 and 81, respectively), had medium attack rates (19.7 and 34.5%, respectively) and a higher proportion of confirmed vehicles (50 and 49%, respectively), compared to those occurring at home (21%) . Salmonella spp . was the most frequent agent detected in each setting (67% of confirmed cases) . The most frequent vehicles at home were mushrooms and sweets containing eggs and cream; in canteens, meat and vegetables and in restaurants, shellfish . CONCLUSIONS: Outbreak characteristics varied according to the setting . This implies the need for a different approach of field investigations, and different preventive measures. Mol Microbiol, 2003 Sep, 49(6), 1565 - 76 The Salmonella SpiC protein targets the mammalian Hook3 protein function to alter cellular trafficking; Shotland Y et al.; The Salmonella SpiC protein is secreted into the cytosol of macrophages via a unique type III secretion system that functions intracellularly to translocate proteins across the phagosomal membrane . The SpiC protein is required for survival within macrophages and inhibition of phagosome-lysosome fusion in vivo, and it is sufficient to inhibit endosome-endosome fusion in vitro . Here, we establish that SpiC targets the function of Hook3, a mammalian protein implicated in cellular trafficking . Purified GST-SpiC pulled down Hook3 from murine macrophages, and anti-Hook3 antibodies precipitated SpiC from the cytosol of Salmonella-infected macrophages . Expression of the spiC gene disrupted Golgi morphology in Vero cells and altered the distribution of lysosomes in macrophages, mimicking the phenotype of cells expressing a hook3 dominant-negative mutant . By inactivating Hook3 function, the SpiC protein may alter the lysosome network and prevent phagosome-lysosome fusion. J Bacteriol, 2003 Sep, 185(18), 5546 - 54 Interactions of FliJ with the Salmonella type III flagellar export apparatus; Fraser GM et al.; FliJ, a 17-kDa protein, is a soluble component of the Salmonella type III flagellar protein export system that has antiaggregation properties and several other characteristics that suggest it may have a chaperone-like function . We have now examined this protein in detail . Ten-amino-acid scanning deletions covering the entire 147-amino-acid sequence were tested for complementation of a fliJ null strain; only the first and last deletions complemented . A few of the deletions, especially towards the C terminus, exerted a dominant negative effect on wild-type cells, indicating that they were actively interfering with function . Two truncated versions of FliJ, representing its N- and C-terminal halves, failed to complement and were not dominant . We tested for FliJ self-association by several techniques . Size-exclusion chromatography (Superdex 200) indicated an apparent molecular mass of around 50 kDa, which could reflect either multimerization or an elongated shape or both . Multiangle light scattering gave a peak value of 20 kDa, close to the molecular mass of the monomer . Analytical ultracentrifugation gave evidence for weak self-association as a trimer or tetramer . It was known from previous studies that FliJ interacts with the N-terminal region of FliH, a negative regulator of the ATPase FliI . Using both truncation and deletion versions of FliJ, we now show that it is its C-terminal region that is responsible for this interaction . We also show that FliJ interacts with the soluble cytoplasmic domain of the largest membrane component of the export apparatus, FlhA; although small deletions in FliJ did not interfere with the association, both truncated versions failed to associate, indicating that a substantial amount of the central region of the FliJ sequence participates in the association . We present a model summarizing these multiple interactions. J Bacteriol, 2003 Sep, 185(18), 5398 - 407 Extracellular polysaccharides associated with thin aggregative fimbriae of Salmonella enterica serovar enteritidis; White AP et al.; Lipopolysaccharide (LPS) O polysaccharide was identified as the principle factor impeding intercellular formation of intact thin aggregative fimbriae (Tafi) in Salmonella enterica serovar Enteritidis . The extracellular nucleation-precipitation assembly pathway for these organelles was investigated by quantifying fimbrial formation between deltaagfA (AgfA recipient) and deltaagfB (AgfA donor) cells harboring mutations in LPS (galE::Tn10) and/or cellulose (deltabcsA) synthesis . Intercellular complementation could be detected between deltaagfA and deltaagfB strains only when both possessed the galE mutation . LPS O polysaccharide appears to be an impenetrable barrier to AgfA assembly between cells but not within individual cells . The presence of cellulose did not restrict Tafi formation between cells . Transmission electron microscopy of w+ S . enterica serovar Enteritidis 3b cells revealed diffuse Tafi networks without discernible fine structure . In the absence of cellulose, however, individual Tafi fibers were clearly visible, appeared to be occasionally branched, and showed the generally distinctive appearance described for Escherichia coli K-12 curli . A third extracellular matrix component closely associated with cellulose and Tafi was detected on Western blots by using immune serum raised to whole, purified Tafi aggregates . Cellulose was required to tightly link this material to cells . Antigenically similar material was also detected in S . enterica serovar Typhimurium and one diarrheagenic E . coli isolate . Preliminary analysis indicated that this material represented an anionic, extracellular polysaccharide that was distinct from colanic acid . Therefore, Tafi in their native state appear to exist as a complex with cellulose and at least one other component. Mutat Res, 2003 Aug 5, 539(1-2), 195 - 201 Mutagenic activity and heterocyclic amine carcinogens in commercial pet foods; Knize MG et al.; Twenty-five commercial pet foods were analyzed for mutagenic activity using the Ames/Salmonella test with strain TA98 and added metabolic activation . All but one gave a positive mutagenic response . Fourteen of these samples were analyzed for heterocyclic amine mutagens/carcinogens and all but one contained 2-amino-3,8-dimethylimidazo{4,5-f}quinoxaline (MeIQx) and 10 of 14 contained 2-amino-1-methyl-6-phenylimidazo{4,5-b}pyridine (PhIP) as analyzed by HPLC and confirmed by photodiode array peak matching . From these findings it is hypothesized that there is a connection between dietary heterocyclic amines and cancer in animals consuming these foods. Mutat Res, 2003 Aug 5, 539(1-2), 29 - 41 Differential mutagenic, antimutagenic and cytotoxic responses induced by apomorphine and its oxidation product, 8-oxo-apomorphine-semiquinone, in bacteria and yeast; Picada JN et al.; Apomorphine (APO) is considered to be a classical mixed type dopamine D(1) and D(2) receptor agonist . It has been used in the therapy of Parkinson's disease and, more recently, for the treatment of erectile dysfunction . Like other catechols (e.g . dopamine), APO easily autoxidizes, producing quinone and semiquinone derivatives that may lead to the formation of reactive oxygen species and induce neurotoxicity . We assayed mutagenicity, antimutagenicity, and cytotoxicity of these compounds by means of the Salmonella/microsome assay, WP2 Mutoxitest and sensitivity assay in Saccharomyces cerevisiae yeast strains lacking antioxidant defenses . In the absence of S9 mix both compounds Apomorphine and its oxidation derivative, 8-oxo-apomorphine-semiquinone (8-OASQ), both at doses ranging from 20 to 80 microg per plate, induced frameshift mutations in TA98 and TA97 S . typhimurium strains, with 8-OASQ being up to two times more mutagenic . However, for strains which detect oxidative mutagens, 8-OASQ acted as a mutagen while APO was an antimutagen, inhibiting H(2)O(2) and t-BOOH-induced mutagenicity in TA102 S . typhimurium and WP2-derived E . coli strains . The S9 mix inhibited all mutagenic effects, probably either by conjugation of APO and 8-OASQ to proteins or by quenching reactive oxygen species . In sensitivity assays with S . cerevisiae, APO was only clearly cytotoxic to some strains at higher doses (200 and 400 microg/ml), whereas 8-OASQ dose-dependently sensitized all the strains, mainly the mutants lacking catalase (deltactt1), superoxide dismutase (deltasod1) and Yap1 transcription factor (deltayap1), suggesting that 8-OASQ cytotoxicity towards S . cerevisiae results from its pro-oxidant properties . APO also tended to protect S . cerevisiae strains against oxidative damage induced by high concentrations of H(2)O(2) and t-BOOH, while 8-OASQ enhanced pro-oxidant effects and induced adaptation responses to these agents . These results suggest that the 8-OASQ oxidation product of APO might induce cytotoxic and genotoxic effects. Epidemiol Infect, 2003 Aug, 131(1), 607 - 12 Molecular epidemiology of Salmonella enteritidis phage type 1b and 6a isolates in Portugal; Soares AR et al.; Salmonella enterica serotype Enteritidis is an important serovar comprising 76 % of Salmonella isolates in Portugal in 2001 . For better understand the epidemiology of salmonellosis, a total of 47 isolates of S . Enteritidis phage type (PT) 1b and 6a were analysed by pulsed-field gel electrophoresis (PFGE) and genomic DNA was subjected to macro restriction with XbaI . For PT 1b isolates, only three different patterns were observed, and PT6a showed a total of 10 digestion patterns . Curiously, the main pattern among PT1b isolates seams quite similar to main pattern of PT6a isolates, but when the two patterns were analysed with Bionumerics, we observed that they exhibited some differences . It was concluded that, in 2001, there was one predominant pattern for PT1b and PT6a and, possibly, we were in presence of clonal strains that exists all over the country. Epidemiol Infect, 2003 Aug, 131(1), 599 - 606 Factors associated with the serological prevalence of Salmonella enterica in Greek finishing swineherds; Leontides LS et al.; Blood samples were taken from 50 finishing pigs at 90-105 kg in each of 59 randomly selected farrow-to-finish herds . The sera were tested for antibodies to Salmonella enterica by the Danish mix-ELISA . Samples with an optical density of > 10% were considered to be positive . Associations between the odds of seropositivity of pigs and possible risk factors were evaluated in multivariable logistic regression models . The results of the analysis indicated that pigs fed non-pelleted dry or wet ration had 11 (P = 0.0004) or 9 (P = 0.02) times, respectively, lower odds of seropositivity than those fed pelleted ration . The risk of seropositivity was 4 (P = 0.0006) times higher in pigs fed a combination of chlortetracycline, procaine penicillin and sulphamethazine during fattening than in those fed an approved growth promotor or a probiotic. Org Biomol Chem, 2003 Jun 21, 1(12), 2075 - 83 Design, synthesis and evaluation of bifunctional inhibitors of type II dehydroquinase; Toscano MD et al.; Inhibitors of type II dehydroquinase were designed to straddle the two distinct binding sites identified for the inhibitor (1S,3R,4R)-1,3,4-trihydroxy-5-cyclohexene-1-carboxylic acid and a glycerol molecule in a crystallographic study of the Streptomyces coelicolor enzyme . A number of compounds were designed to incorporate characteristics of both ligands . These analogues were synthesized from quinic acid, and were assayed against type I (Salmonella typhi) and type II (S . coelicolor) dehydroquinases . None of the analogues showed inhibition for type I dehydroquinase . Six of the analogues were shown to have inhibition constants in the micromolar to low millimolar range against the S . coelicolor type II dehydroquinase, while two showed no inhibition . The binding modes of the analogues in the active site of the S . coelicolor enzyme were studied by molecular docking with GOLD1.2 . These studies suggest a binding mode where the ring is in a similar position to (1S,3R,4R)-1,3,4-trihydroxy-5-cyclohexene-1-carboxylic acid in the crystal structure and the side-chain occupies part of the glycerol binding-pocket. Org Biomol Chem, 2003 Jul 7, 1(13), 2238 - 46 Mutagenicity and DNA damage studies of N-acyloxy-N-alkoxyamides--the role of electrophilic nitrogen; Banks TM et al.; N-Acyloxy-N-alkoxyamides are anomeric amides that are direct-acting mutagens . They have been shown to damage DNA in the major and the minor grooves in a pH and sequence-selective manner . In acidic media, they damage adenines at N3 in the minor groove but above neutral pH, only guanine is damaged at N7 in the major groove . Both the acyloxy leaving group and the alkoxy group at the amide nitrogen are responsible for their electrophilicity and Salmonella mutagenicities in TA 100 and DNA damage data confirm that the mutagens react with DNA in an intact form, rather than by solvolysis to electrophilic nitrenium ions in the cytosol, or in vitro, prior to reacting with DNA . Hydrophobicity plays a role in both mutagenicity and DNA damage. Br J Surg, 2003 Sep, 90(9), 1080 - 4 Management of aortic aneurysm infected with Salmonella; Hsu RB et al.; BACKGROUND: This study reviewed the clinical outcomes of patients with an aortic aneurysm infected with Salmonella treated by a single centre over 6 years . METHODS: Data were collected by a retrospective case-note review . RESULTS: Between September 1995 and December 2001, 121 patients with non-typhoid Salmonella bacteraemia were treated, of whom 24 patients had an aortic aneurysm infected with Salmonella . Ten had a suprarenal and 14 an infrarenal aortic infection . The most common responsible pathogen was group C Salmonella (12 patients) . All of the 20 patients who had combined medical and surgical therapy survived, whereas two of four who had medical therapy alone died . There were two late deaths during a mean follow-up of 23 (range 3-63) months . CONCLUSION: The incidence of aortic infection in patients with non-typhoid Salmonella bacteraemia was high in Taiwan . Timely surgical intervention and prolonged intravenous antibiotic therapy resulted in excellent outcomes . J Clin Pathol, 2003 Sep, 56(9), 694 - 8 Early diagnosis of typhoid fever by the detection of salivary IgA; Herath HM; BACKGROUND:/AIMS: Current diagnostic methods for typhoid fever have low sensitivity and specificity . This study aimed to develop an enzyme linked immunosorbent assay (ELISA) with greater sensitivity and specificity . METHODS: The ELISA was developed and evaluated on patients with acute typhoid infection, febrile controls, and healthy controls . A sequential study on patients with culture confirmed typhoid was also carried out to determine the time period of maximum sensitivity . RESULTS: The ELISA detected anti-Salmonella typhi lipopolysaccharide (LPS) salivary IgA antibodies . A six month follow up study of patients with culture confirmed typhoid fever showed that the test shows maximum efficiency during the second and third weeks of fever and enables detection of the acute infection during the early phase . CONCLUSIONS: This ELISA can detect typhoid fever during the early phase of infection and is most efficient during the second and third weeks of fever, the time at which patients normally present for treatment . Because the sensitivity of the assay is subsequently greatly reduced, it will be useful for the diagnosis of acute infection. Mol Cell Probes, 2003 Aug, 17(4), 183 - 6 Avoidance of false PCR results with the integron-retron junction in multiple antibiotic resistant Salmonella enterica serotype Typhimurium; Carlson SA et al.; Salmonella infections continue to cause gastrointestinal and systemic disease throughout the world . Another concern with this pathogen is the ability to acquire integrons that confer resistance to multiple antibiotics . For multiresistant Salmonella enterica serotype Typhimurium, the most common multiresistant Salmonella serotype, an integron structure can be found between thdF and a retron . Our objective was to investigate the utility of a 450 bp thdF-retron amplicon as an indicator of an insertless thdF-retron junction thus indicating an integron-free strain . Surprisingly, we found that the 450 bp thdF-retron amplicon was present, and thus incorrectly suggesting an integron-free status, in some multiresistant S . enterica serotype Typhimurium isolates . However, this phenomenon was not observed if the isolate was enriched in the presence of two antibiotics . This demonstrates that, within some individual clinical isolates of multiresistant S . enterica serotype Typhimurium, there exists a small subpopulation of integron-free bacteria . Consequently, it appears that the thdF-retron amplicon is an inaccurate predictor of integron status in S . enterica serotype Typhimurium unless multiresistance is used as a selection tool during enrichment. Mutat Res, 2003 Aug 28, 529(1-2), 117 - 27 Synergy between systemic toxicity and genotoxicity: relevance to human cancer risk; Rosenkranz HS; The health risk manager and policy analyst must frequently make recommendations based upon incomplete toxicity data . This is a situation which is encountered in the evaluation of human carcinogenic risks as animal cancer bioassay results are often not available . In this study, in order to assess the relevance of other possible indicators of carcinogenic risks, we used the "chemical diversity approach" to estimate the magnitude of the human carcinogenic risk based upon Salmonella mutagenicity and systemic toxicity data of the "universe of chemicals" to which humans have the potential to be exposed . Analyses of the properties of 10,000 agents representative of the "universe of chemicals" suggest that chemicals that have genotoxic potentials as well as exhibiting greater systemic toxicity are more likely to be carcinogens than non-genotoxicants or agents that exhibit lesser toxicity . Since "genotoxic" carcinogenicity is a hallmark of recognized human carcinogens, these findings are relevant to human cancer risk assessment. Clin Infect Dis, 2003 Sep 1, 37(5), 685 - 91 Epub 2003 Aug 13. Norfloxacin and azithromycin for treatment of nontyphoidal salmonella carriers; Sirinavin S et al.; There has been inadequate evaluation of an antibiotic for eradication of nontyphoidal salmonellae (NTS) in asymptomatic carriers . In a randomized, placebo-controlled trial, such efficacy was evaluated using 2 five-day regimens (norfloxacin, 400 mg twice per day, and azithromycin, 500 mg once per day) compared with placebo . The study included 265 food workers in an area of Thailand where NTS are endemic who were asymptomatic NTS carriers . The presence of NTS in stool samples was assessed on days 7, 30, 60, and 90 after start of treatment . At each assessment visit, <4% of participants in each of the 3 groups carried an initial Salmonella serotype; 16%-35% had new Salmonella serotypes detected, except on day 7 in the azithromycin group, when the rate was 4% . Sanitation was good at work but not at home . Selection of multidrug-resistant Salmonella enterica serotype Schwarzengrund was demonstrated . The study regimens were not better than placebo for treatment of asymptomatic food workers who carried NTS in an area where these organisms are endemic, and use of the regimens resulted in antimicrobial resistance. Euro Surveill, 2003 Jul, 8(7), 151 - 6 Two outbreaks of Salmonella enteritidis phage type 8 linked to the consumption of Cantal cheese made with raw milk, France, 2001; Haeghebaert S et al.; Salmonelloses are one are the main causes of foodborne infections in industrialised countries . In France, the incidence of human salmonellosis recorded by the National Reference Centre for Salmonella and Shigella (CNRSS) in 2001 was 21 cases per 100,000 inhabitants, and Salmonella serotype Enteritidis represented 39% of cases (1) . This article reports the investigation results of two community outbreaks of salmonellosis that occurred simultaneously in the south west of France, and which were linked to the consumption of cheese made from raw milk. Microbes Infect, 2003 Sep, 5(11), 977 - 89 Lateral gene transfer in Salmonella; Porwollik S et al.; Comparative genomics and microarrays reveal that the genomes of different Salmonella enterica serovars are distinguished from each other by the presence or absence of hundreds of genes . The distribution of these variable genome regions is often not clonal . Therefore, lateral gene transfer (LGT) plays an important role in diversity among Salmonella . Overall, almost one quarter of the entire S . enterica sv Typhimurium genome may have been introduced by LGT. Mem Inst Oswaldo Cruz, 2003 Jun, 98(4), 501 - 2 Epub 2003 Aug 18. A new serovar and a new serological variant belonging to Salmonella enterica subspecies diarizonae; Solari CA et al.; Description of a new serovar (S . IIIb 16:k:e,n,x,z15) and a new serological variant (S . IIIb 42:z10:e,n,x,z15:z60 ) belonging to the genus Salmonella isolated from stool specimens of Brazilian snakes (Crotalus durissus). Antimicrob Agents Chemother, 2003 Sep, 47(9), 2859 - 63 Molecular and biochemical characterization of OXA-45, an extended-spectrum class 2d' beta-lactamase in Pseudomonas aeruginosa; Toleman MA et al.; As part of the CANCER Antimicrobial Surveillance Program in North America, a clinical strain of Pseudomonas aeruginosa, strain 07-406, isolated in Texas was found to be resistant to all antimicrobials except polymyxin B . Genetic analysis of this isolate identified two unique extended-spectrum beta-lactamase genes . One, bla(VIM-7), encoded a metallo-beta-lactamase (unpublished data), and the other, bla(OXA-45), described here, encoded a class D extended-spectrum beta-lactamase . bla(OXA-45) was isolated on a Sau3A1 genomic fragment of 1.8 kb and encodes a protein of 264 amino acids with the highest identities to OXA-18 (65.9%), OXA-9 (42.8%), OXA-22 (40.2%), OXA-12 (38.6%), and OXA-29 (35.2%) but weak identities with other class D beta-lactamases . bla(OXA-45) was found to be harbored on a 24-kb plasmid in a region that displays high identities with a section of the 43-kb genomic island of Salmonella enterica serovar Typhimurium DT104 . Biochemically OXA-45 is most similar to OXA-18 in its substrate profile and inhibition by clavulanic acid and is a member of the 2d' class of beta-lactamases. Antimicrob Agents Chemother, 2003 Sep, 47(9), 2732 - 9 Molecular analysis of incHI1 antimicrobial resistance plasmids from Salmonella serovar Typhi strains associated with typhoid fever; Wain J et al.; The first outbreak of multidrug-resistant (MDR) typhoid fever in Vietnam was in 1993, and by 1995 nearly 90% of cases were MDR . Plasmid HCM1, sequenced in full, is an incHI1 plasmid from Salmonella enterica serovar Typhi strain CT18, isolated in Vietnam in 1993 . Restriction analysis shows that pHCM1 shares a restriction fragment length polymorphism (RFLP) pattern with plasmids isolated from the first outbreak and 10 of 17 MDR plasmids isolated from sporadic cases occurring at the same time in Vietnam . A core region of pHCM1 has significant DNA sequence similarity to plasmid R27, isolated in 1961 from S . enterica in the United Kingdom . There are five regions of DNA in pHCM1 which are not present in R27 . Two of these are putative acquisition regions; the largest is 34.955 kbp in length and includes sequences of several antibiotic resistance genes and several insertion sequences . The borders of this region are defined by two identical IS10 left elements, associated with an inversion of DNA or with a truncated Tn10 element . The second, smaller region is 14.751 kbp and carries a trimethoprim resistance gene dfr14A cassette associated with a class 1 integrase . In 1993 to 1994, restriction analysis revealed some variations in the structures of Salmonella serovar Typhi MDR plasmids which were mapped to the two putative acquisition regions and three smaller variable regions . In 1996 a single RFLP type, RFLP7, was found to carry the dfrA7 and sul-1 genes, which were not present on R27 or pHCM1 . This plasmid type appears to have a selective advantage over other plasmids with the same resistance phenotype. Infect Immun, 2003 Sep, 71(9), 5432 - 5 The small nucleoid-binding proteins H-NS, HU, and Fis affect hilA expression in Salmonella enterica serovar Typhimurium; Schechter LM et al.; hilA encodes an activator of Salmonella enterica serovar Typhimurium virulence genes and is transcriptionally modulated by environmental conditions . We show that H-NS represses hilA under low-osmolarity conditions . H-NS, HU, and Fis also appear to affect the derepression of hilA by HilD . Modulation of hilA by counteracting repressing and derepressing mechanisms may allow Salmonella serovar Typhimurium to regulate its virulence genes in response to different situations in vivo. Infect Immun, 2003 Sep, 71(9), 5386 - 8 Role of periplasmic peptidylprolyl isomerases in Salmonella enterica serovar Typhimurium virulence; Humphreys S et al.; FkpA is a peptidylprolyl isomerase whose expression is regulated by the alternative sigma factor, sigma factor E (sigma(E)) . In contrast to the results of a previous report, inactivation of fkpA was found to have only a minor effect on the ability of Salmonella enterica serovar Typhimurium to invade and survive within epithelial and macrophage cell lines and cause infection in mice . However, an effect of the fkpA mutation on serovar Typhimurium virulence was seen if the mutation was combined with mutations in surA or htrA, two other sigma(E)-regulated genes, which encode proteins involved in protein folding and/or degradation in the periplasm. Infect Immun, 2003 Sep, 71(9), 4873 - 82 Role of Toll-like receptor 4 in macrophage activation and tolerance during Salmonella enterica serovar Typhimurium infection; Li Q et al.; Toll-like receptors (TLRs) play an important role in the innate immune response, particularly in the initial interaction between the infecting microorganism and phagocytic cells, such as macrophages . We investigated the role of TLR4 during infection of primary murine peritoneal macrophages with Salmonella enterica serovar Typhimurium . We found that macrophages from the C3H/HeJ mouse strain, which carries a functionally inactive Tlr4 gene, exhibit marked impairment of tumor necrosis factor alpha (TNF-alpha) secretion in response to S . enterica serovar Typhimurium infection . However, activation of extracellular growth factor-regulated kinase and NF-kappa B signaling pathways was relatively unaffected, as was increased expression of TNF-alpha mRNA . Furthermore, macrophage tolerance, which is associated with increased expression of the NF-kappa B p50 and p52 subunits, was induced by S . enterica serovar Typhimurium even in the absence of functional TLR4 . These results indicate that during infection of macrophages by S . enterica serovar Typhimurium, TLR4 signals are required at a posttranscriptional step to maximize secretion of TNF-alpha . Signals delivered by pattern recognition receptors other than TLR4 are sufficient for the increased expression of the TNF-alpha transcript and at least some genes associated with macrophage tolerance. Indian J Med Res, 2003 Feb, 117, 66 - 70 Distribution of virulence genes in Salmonella serovars isolated from man & animals; Murugkar HV et al.; BACKGROUND & OBJECTIVES: Pathogenesis of Salmonellosis depends upon a large number of factors controlled by an array of genes that synergise into the actual virulence of Salmonella . A study was undertaken to observe the distribution of three such genes, namely, Salmonella enterotoxin (stn), Salmonella Enteritidis fimbrial (sef and plasmid encoded fimbrial (pef genes, among different serovars of Salmonella enterica isolated from man and animals . METHODS: A total of 95 isolates belonging to S . Typhimurium (51), S . Enteritidis (36), S . Bareilly (3), and S . Paratyphi B (5) serovars were subjected to polymerase chain reaction (PCR) assay for the detection of stnl ssf and pef genes using their specific primers and the PCR products were analysed by 1 per cent agarose gel electrophoresis for the presence of the respective genes . RESULTS: Varying distribution pattern of these genes was observed amongst the isolates . While, stn was found in all the 95 strains, sef was found only among the S . Enteritidis isolates . The pef gene was found to be absent in 10 isolates including the three S . Bareilly isolates . INTERPRETATION & CONCLUSION: Findings indicated that the stn gene is widely distributed among Salmonella irrespective of the serovars and source of isolation . However, the sef gene appears to be serovar specific . Since the stn gene is found in all the isolates, it can be a viable target gene to explore the possibility of direct detection of Salmonella from samples from biological sources. Kansenshogaku Zasshi, 2003 Jul, 77(7), 516 - 20 {Salmonella enteritidis osteomyelitis of the tibia--a case report and review of literature on Salmonella osteomyelitis of Japanese patients}; Matsubara K et al.; We described a rare case of Salmonella enteritidis osteomyelitis of the tibia combined with arthritis of the ankle joint . A 4-year-old, otherwise healthy girl was hospitalized with 9-day history of fever, left leg pain, and diarrhea . On admission, her left lower leg and ankle were markedly reddened and swollen . Laboratory examinations disclosed a WBC of 16,300/microliter and a C-reactive protein of 15.6 mg/dl . A T2-weighed magnetic resonance image of the leg depicted a high intensity area around the left distal tibia and an extremely high intensity fluid in her left ankle joint, leading to our diagnosis of purulent osteomyelitis of the tibia and arthritis of the ankle joint . Salmonella enteritidis was isolated from ankle joint fluid and later aspirated bone marrow of the tibia, but not from blood or stool . Because of poor response to intravenous treatment with panipenem/betamipron for 2 days, she underwent drainage and washing of the joint fluid, and intramedullary administration of cefotaxime and ampicillin . She completely recovered without sequelae following treatment with sensitive antibiotics for 4 weeks in total . There has not been any relapse for more than 1.5 years . The authors also bibliographically surveyed the literature published from 1966 to 2002 and found 35 Japanese patients with Salmonella osteomyelitis . The present patient was the second case caused by Salmonella enteritidis in Japan . Septic arthritis is a rare complication, accounting for only 8% of the patients . Since Salmonella enteritidis has been a leading serotype among human isolates of Salmonella species during the past decade, it would be warranted to determine whether osteomyelitis due to this organism is likely to increase. J Food Prot, 2003 Aug, 66(8), 1479 - 81 Survival of Staphylococcus aureus and Salmonella enteritidis on salted sardines (Sardina pilchardus) during ripening; Arkoudelos JS et al.; The ripening period for salted sardines ranges from 4 to 6 months, depending on the season . Sometimes producing industries need to distribute the product earlier owing to market needs, and when this happens the product's safety needs to be assured . The purpose of this work was to study the survival of Staphylococcus aureus and Salmonella Enteritidis on salted sardines during a ripening period of 115 days . Salted sardines were inoculated with pure cultures of S . aureus and Salmonella Enteritidis (10(5) CFU/g of fish on day 0) . After 5 days of ripening, the water activity value for the sardines decreased from 0.93 to 0.69 . The survival of both pathogens and that of total viable cells were evaluated during the ripening process . Total viable counts decreased by 2 log units over the 115-day ripening period . Salmonella Enteritidis and S . aureus survived for 60 and 90 days, respectively . Therefore, the use of a 90-day ripening period could be effective in assuring the safety of the final product. J Food Prot, 2003 Aug, 66(8), 1462 - 4 Survivability of Salmonella and Shigella spp . in sodium lauryl sulfate and tween 80 at 22 and 40 degrees C; Raiden RM et al.; Fresh produce has been implicated in several foodborne disease outbreaks . A primary site of contamination during production and handling is the surface of produce . One approach to reducing contamination is to treat fresh produce with rinsing agents . Studies have examined the efficacies of detergents and other rinses in recovering pathogens from produce surfaces . The determination of how these detergents affect bacterial cells may aid in understanding the mechanisms behind their removal . This study examines the survivability of Salmonella and Shigella in two detergents . A 0.1% sodium lauryl sulfate (SLS) solution, a 0.1% Tween 80 solution, and water were inoculated with a cocktail of stationary-phase organisms (3 log CFU/ml) and incubated for up to 32 h at 22 degrees C and 40 degrees C . Samples were taken over time and plated on tryptic soy agar supplemented with 50 ppm of nalidixic acid . Salmonella survived in all solutions and exhibited significant growth in water (0.8 log CFU/ml at 22 degrees C and 1.9 log CFU/ml at 40 degrees C) and Tween 80 (1.0 log CFU/ml at 40 degrees C) . Shigella survived in all solutions at 22 degrees C and exhibited a growth level of 2.0 log CFU/ml in SLS . Shigella also survived in all solutions at 40 degrees C, although its populations decreased significantly in Tween 80 over time . Elevated temperatures may allow Tween 80 to kill Shigella spp . over time . Overall, the detergents tested were not detrimental to the cells; therefore, if these solutions were to be used as produce rinse agents, they would aid in removal of organisms from surfaces rather than kill the cells. J Food Prot, 2003 Aug, 66(8), 1459 - 61 Potential of a plant-parasitic nematode to facilitate internal contamination of tomato plants by Salmonella; Beuchat LR et al.; The objective of this study was to determine whether tomato plants infested with a plant-parasitic nematode, Meloidogne incognita, can internalize Salmonella . Tomato plants (Lycopersicon esculentum Mill . 'Rutgers') were grown in soil infested with M . incognita and/or inoculated with a six-serotype mixture of Salmonella enterica . M . incognita, upon wounding roots when parasitizing the tomato plant, does not result in the entry and survival of Salmonella . Analysis of roots, galls, stems, and leaves 2 and 4 weeks after inoculation of the soil failed to reveal the presence of Salmonella . Salmonella remained viable in soil for at least 4 weeks . The potential for the presence of Salmonella in the tissues of tomato fruits via root entrance facilitated by M . incognita appears to be remote. J Food Prot, 2003 Aug, 66(8), 1368 - 73 Effect of temperature on the growth response of Salmonella enteritidis inoculated onto the vitelline membranes of fresh eggs; Fleischman GJ et al.; The growth response of Salmonella Enteritidis (SE) on the vitelline membrane in vitro was studied with the use of a special tube devised specifically for the inoculation of SE onto the vitelline membrane and for the sampling of the yolk near the inoculation site . This latter ability allowed the detection of the movement of SE into the yolk . The growth of SE on the membrane was compared with that of SE inoculated into yolk and albumen in vitro and in ovo in fresh in-shell eggs . The incubation time was 2 days, and the incubation temperatures were 4, 8, 15, 27, and 37 degrees C . Comparison of the results obtained for in vitro growth showed that at 4, 8, and 15 degrees C, SE behaved as if it were in the albumen, with its numbers decreasing over time . At 27 and 37 degrees C, SE grew as if it were in yolk, with a maximum increase of 4.5 log CFU after 2 days at 37 degrees C . In no experiments involving growth on the vitelline membrane did SE appear in the yolk . Comparisons between in vitro and in ovo growth responses of SE in yolk and albumen indicate that SE growth on the membrane parallels that in the in-shell egg. Int J Antimicrob Agents, 2003 Aug, 22(2), 134 - 9 Characterisation of Salmonella spp . mutants produced by exposure to various fluoroquinolones; Cebrian L et al.; We repeatedly exposed six Salmonella spp . strains of different serotypes (three susceptible to nalidixic acid and three resistant) to constant low concentrations of various fluoroquinolones with the aim of characterising the mutations that produce the first decrease in susceptibility to these agents . The fluoroquinolone-susceptibility of all the strains was reduced after repeated exposure to these agents . However, gyrA mutants were not always produced . Furthermore, the type of mutation produced and the time taken for it to appear varied depending on the initial resistance to nalidixic acid, the antibiotic used and the serotype involved . Therefore, we believe that the initial decrease in quinolone-susceptibility is due to various mechanisms and, in many cases, is not caused by mutations in the gyrA gene Int J Food Microbiol, 2003 Oct 15, 87(1-2), 139 - 44 Simple and rapid methods for detecting Salmonella enteritidis in raw eggs; Seo KH et al.; The Centers for Disease Control and Prevention estimates there were 300,000 cases of Salmonella enteritidis (SE) in 1997 . Egg products were associated with many of the cases . To address this problem, many producers implemented flock surveillance of the SE situation at their facilities . A rapid and simple method for detecting SE from poultry samples is critical for the effective implementation of such testing strategies . A lateral flow device for the detection of SE utilized in this study was manufactured by Neogen, Lansing, MI . The test panel is a presumptive qualitative test system that detects only members of Group D1 Salmonella species . A series of studies were conducted to optimize the test procedure for raw eggs with different sample preparations . A novel antigen extraction method was developed for use with the test panel kit . The detection limit of the test panel kit was increased approximately tenfold when the extraction method was used . Detection of SE was 100% in raw egg pools inoculated with 10 SE cells per ml of egg and incubated at a 1:10 ratio in buffered peptone water (BPW) or tetrathionate brilliant green broth (TBG) for 24 h at 37 degrees C . The developed lateral flow test kit could provide a simple, rapid, and inexpensive method for egg producers and processors to test specifically for Salmonella group D1 serovars, such as SE, in egg samples. Toxicology, 2003 Aug 28, 190(3), 145 - 54 In vitro toxicity and mutagenicity of CoCrMo and Ti6Al wear particles; Katzer A et al.; Contact of wear particles with body fluids can result in widespread dissemination of extractable constituents from joint implants . The aim of this in vitro study is to clarify whether there is a mutagenic and/or carcinogenic risk from CoCrMo and Ti6Al wear particles . Particles of a representative size were produced by fretting; toxicity and mutagenicity were investigated using the salmonella/microsome test according to AMES and the V79-HGPRT Test (Chinese Hamster Fibroblasts) . To obtain the greatest possible elution of all constituents the metallic wear particles were extracted with dimethylsulfoxyd and water and the resulting eluates mixed together . Neither the bacterial assay nor the mammalian cell system after repeated test series under standardised conditions produced evidence of a toxic or mutagenic effect in the concentration range under study . It is therefore not to be expected that CoCrMo or Ti6Al alloys initiate carcinogenesis in the human organism. Genet Sel Evol, 2003, 35 Suppl 1, S99 - 111 Association of INOS, TRAIL, TGF-beta2, TGF-beta3, and IgL genes with response to Salmonella enteritidis in poultry; Malek M et al.; Several candidate genes were selected, based on their critical roles in the host's response to intracellular bacteria, to study the genetic control of the chicken response to Salmonella enteritidis (SE) . The candidate genes were: inducible nitric oxide synthase (INOS), tumor necrosis factor related apoptosis inducing ligand (TRAIL), transforming growth factor beta2 (TGF-beta2), transforming growth factor beta3 (TGF-beta3), and immunoglobulin G light chain (IgL) . Responses to pathogenic SE colonization or to SE vaccination were measured in the Iowa Salmonella response resource population (ISRRP) . Outbred broiler sires and three diverse, highly inbred dam lines produced 508 F1 progeny, which were evaluated as young chicks for either bacterial load isolated from spleen or cecum contents after pathogenic SE inoculation, or the circulating antibody level after SE vaccination . Fragments of each gene were sequenced from the founder lines of the resource population to identify genomic sequence variation . Single nucleotide polymorphisms (SNP) were identified, then PCR-RFLP techniques were developed to genotype the F1 resource population . Linear mixed models were used for statistical analyses . Because the inbred dam lines always contributed one copy of the same allele, the heterozygous sire allele effects could be assessed in the F1 generation . Association analyses revealed significant effects of the sire allele of TRAIL-StyI on the spleen (P <0.07) and cecum (P <0.0002) SE bacterial load . Significant effects (P <0.04) were found on the cecum bacterial load for TGF-beta3-BsrI . Varied and moderate association was found for SE vaccine antibody response for all genes . This is the first reported study on the association of SNP in INOS, TRAIL, TGF-beta2, TGF-beta3, and IgL with the chicken response to SE . Identification of candidate genes to improve the immune response may be useful for marker-assisted selection to enhance disease resistance. Przegl Epidemiol, 2003, 57(1), 201 - 9 {Antimicrobial susceptibility and phage types of Salmonella enteritidis strains isolated in the Lublin area}; Kowalczyk-Pecka D et al.; The study aimed at specifying the value of two traditional methods of typing, using the collection of 241 strains of Salmonella Enteritidis isolated from people and animals in the Lublin area in 1994-1995 from the occasional cases of infections . There were 8 phage types identified among the examined strains . Phage types PT 6 (40.24% of strains) and PT 7 (29.46%) were the most numerous ones . Salmonella Enteritidis was numbered among 38 profiles on the basis of the analysis of resistance to 15 antimicrobial agents . It was found that nitrofurantoin had the lowest efficacy in vitro in relation to the examined collection of Salmonella isolates . High percentage of strains were characterized by lack of susceptibility to streptomycin, neomycin, cefixime, tetracycline and canamycine . While analyzing the profiles of resistance to chemiotherapeutics and the expression of phage type of the examined strains it was observed that only 14.1% of all strains showing resistance to nitrofurantoin represented at the same time phage type PT 6, whereas 10.8% of strains belonging to the same resistance profile indicated PT 7 phage type . In correlated analysis of resistance to chemiotherapeutics and phage type expression of the examined collection of 241 isolates of Salmonella Enteritidis, 18.3% of strains showed distinct and unique set of these two features, which can be used in epidemiological investigations for the preliminary characterization of the bacterial population. Przegl Epidemiol, 2003, 57(1), 85 - 98 {Foodborne infections and intoxications in Poland in 2001}; Przybylska A; A total of 24,393 bacterial foodborne infections and intoxications were registered in 2001 . The incidence was 63.1/100,000 population . S . Enteritidis was found in 93.4% of cases in outbreaks (in Poland 4 sick people and more) caused by Salmonella sp . The main vehicle of foodborne and waterborne outbreaks was food prepared from eggs (31.8% cases in outbreaks, 45.2% cases caused by Salmonella of animal's source) . Private homes prevailed (47.9% of outbreaks, 62.6% of outbreaks caused by Salmonella) among the places of the ready made food production . Seven epidemics with more than 100 cases each, were registered . Ten deaths were noted in outbreaks in 2001 (1--in the result of salmonellosis of the animals's source and 9--after chemical poisoning). Przegl Epidemiol, 2003, 57(1), 9 - 17 {Infectious diseases in Poland in 2001}; Zielinski A et al.; In 2001 surveillance system of infectious diseases in Poland remained unchanged . New cases of infectious diseases were recorded in 103 positions including intoxications . Tuberculosis and sexually transmitted infections were registered in separate systems . Influenza was the most frequently reported infectious disease with 576,449 cases, 63.9% less then in the previous year . The next most numerous were foodborne infections, which were reported in 24,393 cases, including 19,788 cases of infections caused by Salmonella sp . An increase in incidence was observed in the following diseases: viral hepatitis type A, rubella, measles and pertussis . Also the number of recorded cases of Lyme boreliosis and tickborne encephalitis were higher then in 2000 . Incidence of AIDS remained within the range recorded during the last few years . In 2001 further drop in incidence of viral hepatitis type B was observed reaching the level of 6.2 per 100,000 . It was the result of implemented comprehensive program of prophylactic measures, which brought incidence of this disease from the highest in Europe down to the level close to European average . Infectious diseases contributed to 0.75% of deaths . The most frequent cause of death among infectious diseases was tuberculosis and its sequels (1,061 cases) . 13 cases of death due to tuberculosis occurred in people below 30 years of age. Cell Microbiol, 2003 Sep, 5(9), 593 - 600 Dynamics of bacterial growth and distribution within the liver during Salmonella infection; Sheppard M et al.; Salmonella enterica causes severe systemic diseases in humans and animals and grows intracellularly within discrete tissue foci that become pathological lesions . Because of its lifestyle Salmonella is a superb model for studying the in vivo dynamics of bacterial distribution . Using multicolour fluorescence microscopy in the mouse typhoid model we have studied the interaction between different bacterial populations in the same host as well as the dynamic evolution of foci of infection in relation to bacterial growth and localization . We showed that the growth of Salmonella in the liver results in the spread of the microorganisms to new foci of infection rather than simply in the expansion of the initial ones . These foci were associated with independently segregating bacterial populations and with low numbers of bacteria in each infected phagocyte . Using fast-growing and slow-growing bacteria we also showed that the increase in the number of infected phagocytes parallels the net rate of bacterial growth of the microorganisms in the tissues . These findings suggest a novel mechanism underlying growth of salmonellae in vivo with important consequences for understanding mechanisms of resistance and immunity. Clin Microbiol Infect, 2003 Jul, 9(7), 727 - 30 Molecular epidemiology of invasive Salmonella typhi in southeast Turkey; Hosoglu S et al.; The objective of this study was to determine the molecular epidemiology of Salmonella typhi isolates from patients with typhoid fever in southeast Turkey and to determine the relationship between the clinical strains and environmental subtypes . Both demographic and clinical data were obtained by chart review and compared to the molecular subtyping results. J Bacteriol, 2003 Sep, 185(17), 5295 - 300 Purification and characterization of the flagellar basal body of Rhodobacter sphaeroides; Kobayashi K et al.; Flagellar hook-basal body (HBB) complexes were purified from Rhodobacter sphaeroides . The HBB was more acid labile but more heat stable than that of Salmonella species, and protein identification revealed that HBB components were expressed only from one of the two sets of flagellar gene clusters on the R . sphaeroides genome, under the heterotrophic growth conditions tested here. J Bacteriol, 2003 Sep, 185(17), 5192 - 9 Thin pilus PilV adhesins of plasmid R64 recognize specific structures of the lipopolysaccharide molecules of recipient cells; Ishiwa A et al.; IncI1 plasmid R64 encodes a type IV pilus called a thin pilus, which includes PilV adhesins . Seven different sequences for the C-terminal segments of PilV adhesins can be produced by shufflon DNA rearrangement . The expression of the seven PilV adhesins determines the recipient specificity in liquid matings of plasmid R64 . Salmonella enterica serovar Typhimurium LT2 was recognized by the PilVA' and PilVB' adhesins, while Escherichia coli K-12 was recognized by the PilVA', PilVC, and PilVC' adhesins . Lipopolysaccharide (LPS) on the surfaces of recipient cells was previously shown to be the specific receptor for the seven PilV adhesins . To identify the specific receptor structures of LPS for various PilV adhesins, R64 liquid matings were carried out with recipient cells consisting of various S . enterica serovar Typhimurium LT2 and E . coli K-12 waa mutants and their derivatives carrying various waa genes of different origins . From the mating experiments, including inhibition experiments, we propose that the GlcNAc(alpha1-2)Glc and Glc(alpha1-2)Gal structures of the LPS core of S . enterica serovar Typhimurium LT2 function as receptors for the PilVB' and PilVC' adhesins, respectively, while the PilVC' receptor in the wild-type LT2 LPS core may be masked . We further propose that the GlcNAc(beta1-7)Hep and Glc(alpha1-2)Glc structures of the LPS core of E . coli K-12 function as receptors for the PilVC and PilVC' adhesins, respectively. J Bacteriol, 2003 Sep, 185(17), 5182 - 91 The SopEPhi phage integrates into the ssrA gene of Salmonella enterica serovar Typhimurium A36 and is closely related to the Fels-2 prophage; Pelludat C et al.; Salmonella spp . are enteropathogenic gram-negative bacteria that use a large array of virulence factors to colonize the host, manipulate host cells, and resist the host's defense mechanisms . Even closely related Salmonella strains have different repertoires of virulence factors . Bacteriophages contribute substantially to this diversity . There is increasing evidence that the reassortment of virulence factor repertoires by converting phages like the GIFSY phages and SopEPhi may represent an important mechanism in the adaptation of Salmonella spp . to specific hosts and to the emergence of new epidemic strains . Here, we have analyzed in more detail SopEPhi, a P2-like phage from Salmonella enterica serovar Typhimurium DT204 that encodes the virulence factor SopE . We have cloned and characterized the attachment site (att) of SopEPhi and found that its 47-bp core sequence overlaps the 3' terminus of the ssrA gene of serovar Typhimurium . Furthermore, we have demonstrated integration of SopEPhi into the cloned attB site of serovar Typhimurium A36 . Sequence analysis of the plasmid-borne prophage revealed that SopEPhi is closely related to (60 to 100% identity over 80% of the genome) but clearly distinct from the Fels-2 prophage of serovar Typhimurium LT2 and from P2-like phages in the serovar Typhi CT18 genome . Our results demonstrate that there is considerable variation among the P2-like phages present in closely related Salmonella spp. J Bacteriol, 2003 Sep, 185(17), 5125 - 32 Anthranilate synthase can generate sufficient phosphoribosyl amine for thiamine synthesis in Salmonella enterica; Ramos I et al.; In bacteria, the biosynthetic pathway for the hydroxymethyl pyrimidine moiety of thiamine shares metabolic intermediates with purine biosynthesis . The two pathways branch after the compound aminoimidazole ribotide . Past work has shown that the first common metabolite, phosphoribosyl amine (PRA), can be generated in the absence of the first enzyme in purine biosynthesis, PurF . PurF-independent PRA synthesis is dependent on both strain background and growth conditions . Standard genetic approaches have not identified a gene product singly responsible for PurF-independent PRA formation . This result has led to the hypothesis that multiple enzymes contribute to PRA synthesis, possibly as the result of side products from their dedicated reaction . A mutation that was able to restore PRA synthesis in a purF gnd mutant strain was identified and found to map in the gene coding for the TrpD subunit of the anthranilate synthase (AS)-phosphoribosyl transferase (PRT) complex . Genetic analyses indicated that wild-type AS-PRT was able to generate PRA in vivo and that the P362L mutant of TrpD facilitated this synthesis . In vitro activity assays showed that the mutant AS was able to generate PRA from ammonia and phosphoribosyl pyrophosphate . This work identifies a new reaction catalyzed by AS-PRT and considers it in the context of cellular thiamine synthesis and metabolic flexibility. J Bacteriol, 2003 Sep, 185(17), 5096 - 108 RtsA and RtsB coordinately regulate expression of the invasion and flagellar genes in Salmonella enterica serovar Typhimurium; Ellermeier CD et al.; Salmonella enterica serovar Typhimurium encounters numerous host environments and defense mechanisms during the infection process . The bacterium responds by tightly regulating the expression of virulence genes . We identified two regulatory proteins, termed RtsA and RtsB, which are encoded in an operon located on an island integrated at tRNA(PheU) in S . enterica serovar Typhimurium . RtsA belongs to the AraC/XylS family of regulators, and RtsB is a helix-turn-helix DNA binding protein . In a random screen, we identified five RtsA-regulated fusions, all belonging to the Salmonella pathogenicity island 1 (SPI1) regulon, which encodes a type III secretion system (TTSS) required for invasion of epithelial cells . We show that RtsA increases expression of the invasion genes by inducing hilA expression . RtsA also induces expression of hilD, hilC, and the invF operon . However, induction of hilA is independent of HilC and HilD and is mediated by direct binding of RtsA to the hilA promoter . The phenotype of an rtsA null mutation is similar to the phenotype of a hilC mutation, both of which decrease expression of SPI1 genes approximately twofold . We also show that RtsA can induce expression of a SPI1 TTSS effector, slrP, independent of any SPI1 regulatory protein . RtsB represses expression of the flagellar genes by binding to the flhDC promoter region . Repression of the positive activators flhDC decreases expression of the entire flagellar regulon . We propose that RtsA and RtsB coordinate induction of invasion and repression of motility in the small intestine. J Bacteriol, 2003 Sep, 185(17), 5086 - 95 Protein content of polyhedral organelles involved in coenzyme B12-dependent degradation of 1,2-propanediol in Salmonella enterica serovar Typhimurium LT2; Havemann GD et al.; Salmonella enterica forms polyhedral organelles during coenzyme B(12)-dependent growth on 1,2-propanediol (1,2-PD) . Previously, these organelles were shown to consist of a protein shell partly composed of the PduA protein, the majority of the cell's B(12)-dependent diol dehydratase, and additional unidentified proteins . In this report, the polyhedral organelles involved in B(12)-dependent 1,2-PD degradation by S . enterica were purified by a combination of detergent extraction and differential and density gradient centrifugation . The course of the purification was monitored by electron microscopy and gel electrophoresis, as well as enzymatic assay of B(12)-dependent diol dehydratase . Following one- and two-dimensional gel electrophoresis of purified organelles, the identities and relative abundance of their constituent proteins were determined by N-terminal sequencing, protein mass fingerprinting, Western blotting, and densitometry . These analyses indicated that the organelles consisted of at least 15 proteins, including PduABB'CDEGHJKOPTU and one unidentified protein . Seven of the proteins identified (PduABB'JKTU) have some sequence similarity to the shell proteins of carboxysomes (a polyhedral organelle involved in autotrophic CO(2) fixation), suggesting that the S . enterica organelles and carboxysomes have a related multiprotein shell . In addition, S . enterica organelles contained four enzymes: B(12)-dependent diol dehydratase, its putative reactivating factor, aldehyde dehydrogenase, and ATP cob(I)alamin adenosyltransferase . This complement of enzymes indicates that the primary catalytic function of the S . enterica organelles is the conversion of 1,2-PD to propionyl coenzyme A (which is consistent with our prior proposal that the S . enterica organelles function to minimize aldehyde toxicity during growth on 1,2-PD) . The possibility that similar protein-bound organelles may be more widespread in nature than currently recognized is discussed. J Bacteriol, 2003 Sep, 185(17), 5055 - 65 Composition, acquisition, and distribution of the Vi exopolysaccharide-encoding Salmonella enterica pathogenicity island SPI-7; Pickard D et al.; Vi capsular polysaccharide production is encoded by the viaB locus, which has a limited distribution in Salmonella enterica serovars . In S . enterica serovar Typhi, viaB is encoded on a 134-kb pathogenicity island known as SPI-7 that is located between partially duplicated tRNA(pheU) sites . Functional and bioinformatic analysis suggests that SPI-7 has a mosaic structure and may have evolved as a consequence of several independent insertion events . Analysis of viaB-associated DNA in Vi-positive S . enterica serovar Paratyphi C and S . enterica serovar Dublin isolates revealed the presence of similar SPI-7 islands . In S . enterica serovars Paratyphi C and Dublin, the SopE bacteriophage and a 15-kb fragment adjacent to the intact tRNA(pheU) site were absent . In S . enterica serovar Paratyphi C only, a region encoding a type IV pilus involved in the adherence of S . enterica serovar Typhi to host cells was missing . The remainder of the SPI-7 islands investigated exhibited over 99% DNA sequence identity in the three serovars . Of 30 other Salmonella serovars examined, 24 contained no insertions at the equivalent tRNA(pheU) site, 2 had a 3.7-kb insertion, and 4 showed sequence variation at the tRNA(pheU)-phoN junction, which was not analyzed further . Sequence analysis of the SPI-7 region from S . enterica serovar Typhi strain CT18 revealed significant synteny with clusters of genes from a variety of saprophytic bacteria and phytobacteria, including Pseudomonas aeruginosa and Xanthomonas axonopodis pv . citri . This analysis suggested that SPI-7 may be a mobile element, such as a conjugative transposon or an integrated plasmid remnant. Curr Issues Mol Biol, 2003 Oct, 5(4), 113 - 22 Plasmid-mediated antimicrobial resistance in Salmonella enterica; Carattoli A; The selective pressure imposed by the use of antimicrobials in both human and veterinary medicine promotes the spread of multiple antimicrobial resistance . The dissemination of antimicrobial resistance in Salmonella enterica strains, causing severe enteritis in human, has been reported worldwide and is largely attributed to conjugative DNA exchange . In the present review, the relevance of plasmids to the dissemination of antimicrobial resistance in S . enterica is discussed . Recent examples of plasmid-mediated resistance to expanded-spectrum cephalosporins are reported to illustrate the severity of current situation in enteric pathogens . The exchanges between plasmid(s) and the bacterial chromosome and the integration of resistance genes into specialised genetic elements, called integrons, play a major role in acquisition and dissemination of resistance genes . The evolution of a plasmid through the acquisition of integrons is reported, describing novel mechanisms for short-term accumulation of resistance determinants in plasmids circulating in Salmonella. Microbes Infect, 2003 Aug, 5(10), 841 - 50 AFLP analysis of Salmonella enterica serovar Typhimurium isolates of phage types DT 9 and DT 135: diversity within phage types and its epidemiological significance; Lan R et al.; Amplified fragment length polymorphism (AFLP) was applied to 35 and 34 isolates, respectively, of Salmonella enterica serovar Typhimurium phage types DT 9 and DT 135, using eight primer pair combinations . Eight and 17 AFLP types were observed in DT 9 and DT 135, respectively . DT 9 is rare in the UK and common in Australia, but one AFLP form dominated with 28 isolates, comprising 22 of 25 UK isolates, four of five Australian isolates, one Jamaican and one Spanish isolate . Of the others, two UK isolates are closely related to the major form, two from elsewhere are in the major cluster and three isolates from different countries are in a separate cluster . For DT 135, two closely related AFLP types of seven and 11 isolates form the major cluster, which also includes 11 isolates, mostly in single-isolate AFLP types, while five isolates from different countries form a well-separated minor cluster . For both DTs all isolates are grouped together if only the phage type specific bands identified earlier are used, confirming their value for molecular-based 'phage typing' . Polymorphic markers identified in this study could also be used for subtyping within both phage types . The value of AFLP is in locating DNA fragments useful for typing, but implementation of a replacement typing scheme would probably involve multiplex PCR or microarray technologies. Biomol Eng, 2003 Jul, 20(4-6), 255 - 9 Potent antibacterial activity of halogenated metabolites from Malaysian red algae, Laurencia majuscula (Rhodomelaceae, Ceramiales); Vairappan CS; Red algae genus Laurencia (Rhodomelaceae, Ceramiales) are known to produce a wide range of chemically interesting secondary halogenated metabolites . This investigation delves upon extraction, isolation, structural elucidation and antibacterial activity of inherently available secondary metabolites of Laurencia majuscula Harvey collected from two locations in waters of Sabah, Malaysia . Two major halogenated compounds, identified as elatol (1) and iso-obtusol (2) were isolated . Structures of these compounds were determined from their spectroscopic data such as IR, 1H-NMR, 13C-NMR and optical rotation . Antibacterial bioassay against human pathogenic bacteria was conducted using disc diffusion (Kirby-Bauer) method . Elatol (1) inhibited six species of bacteria, with significant antibacterial activities against Staphylococcus epidermis, Klebsiella pneumonia and Salmonella sp . while iso-obtusol (2) exhibited antibacterial activity against four bacterial species with significant activity against K . pneumonia and Salmonella sp . Elatol (1) showed equal and better antibacterial activity compared with tested commercial antibiotics while iso-obtusol (2) only equaled the potency of commercial antibiotics against K . pneumonia and Salmonella sp . Further tests conducted using dilution method showed both compounds as having bacteriostatic mode of action against the tested bacteria. J Vet Diagn Invest, 2003 Jul, 15(4), 382 - 7 Comparison of phenotypic traits and genetic relatedness of Salmonella enterica subspecies arizonae isolates from a colony of ridgenose rattlesnakes with osteomyelitis; Bemis DA et al.; Reptiles are well-known sources of human Salmonella infections; however, little is known about the ability of Salmonella to cause disease in reptiles . Thirty-seven isolates of Salmonella enterica subspecies arizonae (S . arizonae) were obtained from retrospective and prospective studies of a closed colony of ridgenose rattlesnakes (Crotalus willardi) with osteomyelitis . All isolates (N = 7) from bone lesions were of a single serotype, 56:z4,z23, and this serotype was found on only 1 occasion among 8 other serotypes isolated from 21 cloacal and intestinal samples . The remainder (N = 7) of serotype 56:z4,z23 isolates were from other extraintestinal sites, including liver, ovary, blood, and testis . S . arizonae isolates were susceptible to most antimicrobials, and plasmid profiles did not correlate with serotype or antimicrobial resistance . Isolates of the 56:z4,z23 serotype (N = 14) formed a tight cluster with 95% similarity by XbaI macrorestriction analysis . Individual isolates of serotypes, 56:z4,z23, 38:(k)-z35, and 48:i-z invaded HeLa cells but an isolate of serotype 50:r-z did not . The same individual isolates of serotype 56:z4,z23 and 48:i-z also invaded viper heart cells . The Salmonella InvA gene was detected by polymerase chain reaction (PCR) in all S . arizonae serotypes tested, including 5 serotype 56:z4,z23 isolates and individual isolates of serotypes 48:i-z and 50:r-z . A source or possible explanation for increased virulence of S . arizonae serotype 56:z4,z23 in this unique host has not been found. J Antimicrob Chemother, 2003 Sep, 52(3), 500 - 2 Epub 2003 Aug 13. Activity of faropenem and imipenem for ciprofloxacin-resistant bacteria; Piddock LJ et al.; AIM: To determine whether an association exists between ciprofloxacin and faropenem resistance in bacteria including multiply drug-resistant isolates . METHODS: The MICs were determined for 150 fluoroquinolone-resistant bacteria, plus 20 nalidixic acid-resistant strains of Salmonella enterica serovar Typhimurium . RESULTS: Faropenem was very active against Escherichia coli and Streptococcus pneumoniae, but 5/31 Staphylococcus aureus and 2/26 Bacteroides fragilis required > or =16 mg/L for inhibition . Of 30 multiply drug-resistant isolates with a phenotype suggestive of enhanced efflux, only for one strain (a Bacteroides fragilis) was the faropenem MIC higher than that associated with the other isolates of the same species . CONCLUSIONS: Faropenem was in general as active as imipenem . There was no association between resistance to ciprofloxacin and faropenem or imipenem resistance. J Antimicrob Chemother, 2003 Sep, 52(3), 493 - 6 Epub 2003 Aug 13. Diversity of TEM-52 extended-spectrum beta-lactamase-producing non-typhoidal Salmonella isolates in Korea; Lee K et al.; OBJECTIVES: Extended-spectrum beta-lactamase (ESBL)-producing non-typhoidal Salmonella (NTS) isolates in Korea were characterized . PATIENTS AND METHODS: Five isolates of ESBL-producing NTS were isolated from stool specimens of three infants and two adults with diarrhoea . Two infants acquired the infection in the community, and three other infections were hospital acquired . RESULTS: The isolates were one each of serovars Saintpaul, Stanley and Agona, and two Enteritidis . Cell sonicates of the isolates hydrolysed cefotaxime more efficiently than ceftazidime, and had beta-lactamase bands of approximate isoelectric points 6.0 and 7.4 . Sequencing revealed that the beta-lactamases were TEM-52 and an OXA type . The blaOXA gene was located on a class 1 integron . Cefotaxime resistance, associated with TEM-52, was transferred by conjugation . Identical pulsed-field gel electrophoresis patterns of XbaI-digested genomic DNA were observed in initially beta-lactam-susceptible serovar Agona isolates and subsequent ESBL-producing isolates from an infant, and in two isolates of serovar Enteritidis from two different patients . CONCLUSIONS: This study suggests that TEM-52-producing NTS is spreading both clonally and horizontally in Korea. Traffic, 2003 Sep, 4(9), 587 - 99 Taking possession: biogenesis of the Salmonella-containing vacuole; Knodler LA et al.; The Gram-negative pathogen Salmonella enterica can survive and replicate within a variety of mammalian cells . Regardless of the cell type, internalized bacteria survive and replicate within the Salmonella-containing vacuole, the biogenesis of which is dependent on bacterially encoded virulence factors . In particular, Type III secretion systems translocate bacterial effector proteins into the eukaryotic cell where they can specifically interact with a variety of targets . Salmonella has two distinct Type III secretion systems that are believed to have completely different functions . The SPI2 system is induced intracellularly and is required for intracellular survival in macrophages; it plays no role in invasion but is categorized as being required for Salmonella-containing vacuole biogenesis . In contrast, the SPI1 Type III secretion system is induced extracellularly and is essential for invasion of nonphagocytic cells . Its role in post-invasion processes has not been well studied . Recent studies indicate that Salmonella-containing vacuole biogenesis may be more dependent on SPI1 than previously believed . Other non-SPI2 virulence factors and the host cell itself may play critical roles in determining the intracellular environment of this facultative intracellular pathogen . In this review we discuss the recent advances in determining the mechanisms by which Salmonella regulate Salmonella-containing vacuole biogenesis and the implications of these findings. J Appl Microbiol, 2003, 95(3), 437 - 50 Metabiosis of proteolytic moulds and Salmonella in raw, ripe tomatoes; Wade WN et al.; AIMS: The aim of this study was to determine the survival and growth characteristics of Salmonella enterica in sound and chill-injured tomatoes as influenced by co-infection with proteolytic moulds . METHODS AND RESULTS: Sound (not chill injured) raw, ripe tomatoes (Lycopersicon esculentum Mill . 'Roma') were inoculated with a five-serotype mixture of S . enterica and/or Alternata alternata (two strains), Cladosporium herbarum and C . cladosporioides . Simultaneous and delayed (3 days) inoculation of tomatoes with Salmonella and each mould was studied . Growth of moulds in sound tomatoes stored at 15 and 25 degrees C for up to 10 days was accompanied by increased pH of radial pericarp tissue (pulp), which enhanced the growth of Salmonella . Growth of moulds and Salmonella at 25 degrees C was enhanced in chill-injured tomatoes compared with sound tomatoes . CONCLUSIONS: Growth of proteolytic moulds in tomatoes stored at conditions simulating those commonly used in commercial postharvest storage and handling promotes the growth of Salmonella that may be an incidental contaminant . SIGNIFICANCE AND IMPACT OF THE STUDY: Discarding tomatoes that are infected by moulds is important in handling and minimal processing practices designed to minimize the risk of human salmonellosis. J Wildl Dis, 2003 Apr, 39(2), 359 - 65 Hematology, plasma biochemistry, and serosurvey for selected infectious agents in southern giant petrels from Patagonia, Argentina; Uhart MM et al.; In conjunction with reproductive and feeding ecology studies on southern giant petrels (SGP, Macronectes giganteus) blood samples were collected for baseline health evaluations . Twenty-five adult SGP from a breeding colony in Chubut, Argentina, were sampled during two consecutive breeding seasons, 1999-2000 (n = 15) and 2000-01 (n = 10) . Values for hematology, plasma biochemistry, and minerals are described for 20 birds in apparent good physical condition . A serologic survey of exposure to selected infectious agents was also conducted on all 25 birds sampled . Southern giant petrels were serologically negative for evidence of exposure to infectious laryngotracheitis virus, avian encephalomyelitis virus, avian influenza virus, avian reovirus, infectious bursal disease virus, infectious bronchitis virus, paramyxovirus 1, 2, and 3 virus, Chlamydophila, and Aspergillus . Antibodies to avian adenovirus were found in 14% of SGP during the first sampling season, and 60% in the second year . Additionally, all birds were negative for antibodies to Salmonella pullorum at the first sampling date, but 90% had low titers the following breeding season . This study contributes to understanding the health status of South Atlantic seabirds and to establishment of baseline information for SGP . Long-term monitoring of pelagic predator-scavenger seabirds such as SGP should be established for the surveillance of marine ecosystem health. J Med Microbiol, 2003 Sep, 52(Pt 9), 741 - 5 Anaerobiosis-induced virulence of Salmonella enterica subsp . enterica serovar Typhimurium: role of phospholipase Cgamma signalling cascade; Khullar M et al.; Salmonella enterica subsp . enterica serovar Typhimurium (S . Typhimurium) can initiate entry into non-phagocytic epithelial cells by triggering certain signal transduction pathways, thereby allowing the pathogen to invade and establish a niche within host cells . Anaerobiosis has been shown to be an important inducer of the invasion process of S . Typhimurium . However, the effect of anaerobiosis on modulation of cell signalling cascades by S . Typhimurium is not known . In the present study, the phospholipase Cgamma signalling cascade was investigated in mice enterocytes, following interaction with S . Typhimurium grown under aerobic and anaerobic growth conditions . Significant increases in enterocyte intracellular calcium and inositol 1,4,5-triphosphate levels were observed on interaction with S . Typhimurium grown anaerobically compared with S . Typhimurium grown aerobically . An increased membrane/cytosolic ratio of protein kinase C was also seen with anaerobic S . Typhimurium in enterocytes compared with aerobic S . Typhimurium . These data suggest that anaerobically grown organisms are more efficient in initiating cell-signalling events than are aerobically grown bacteria . These enhanced cell signals may contribute to the increased virulence of S . Typhimurium grown anaerobically. J Biol Chem, 2003 Oct 24, 278(43), 42361 - 8 Epub 2003 Aug 08. Endotoxin contamination of ovalbumin suppresses murine immunologic responses and development of airway hyper-reactivity; Watanabe J et al.; The reversible airway hyper-reactivity (AHR) of asthma is modeled by sensitizing and challenging mice with aerosolized ovalbumin . However, the C57BL/6 murine strain does not display the large increase in circulating IgG and IgE antibodies found in human atopy and asthma . We found that commercial ovalbumin was contaminated with lipopolysaccharide (LPS) in amounts sufficient to fully activate endothelial cells in an in vitro assay of the first step of inflammation . Desensitization of TLR4 by LPS pretreatment suppressed the inflammatory effect of ovalbumin . The presence of LPS was occult, because it does not require serum presentation and, like the LPS of Salmonella minnesota, was not suppressed by polymyxin B . Purified ovalbumin did not activate endothelial cells in vitro; however, endotoxin-free ovalbumin was far more effective than commercial material in stimulating IgE production and respiratory dysfunction in a C57BL/6 murine model of AHR . Moreover, endotoxin-free ovalbumin induced lung inflammation with alveolar enlargement and destruction in a histologic pattern that differed from the changes caused by commercial, endotoxin-contaminated ovalbumin . Reconstitution of purified ovalbumin with S . minnesota LPS decreased lung inflammation, decreased changes in lung function, and suppressed anti-ovalbumin antibody production . We conclude endotoxin contaminates ovalbumin preparations and that endotoxin co-administration with the ovalbumin antigen creates a state of tolerance in a murine model of AHR . Co-exposure to endotoxin and antigen occurs in humans through organic dusts, so murine models of AHR may reflect the clinical situation, but models based on commercial ovalbumin do not accurately reflect the effect of protein antigen alone on animal physiology. Arch Pediatr, 2003 Jul, 10(7), 608 - 14 {Ciprofloxacin after clinical failure of beta-lactam antibiotics in children with salmonellosis}; Moulin F et al.; BACKGROUND: Children with enteric fever or severe salmonella infections are usually treated with beta-lactam antibiotics, particularly ceftriaxone . Due to their poor penetration into cells, beta-lactam antibiotics, even if active in vitro, are sometimes clinically ineffective because they cannot reach the intracellular sites of Salmonella multiplication . OBJECTIVES: To evaluate in a retrospective study usefulness, efficacy and safety of oral ciprofloxacin in patients with severe salmonellosis and clinical failure of ceftriaxone or beta-lactam antibiotics . PATIENTS AND METHODS: From July 1, 1995 to 2000, the bacteriology laboratory of a French pediatric hospital had identified 215 patients aged between 1 month and 15 years with positive blood or stools for Salmonella sp, 113 of them requiring hospitalization due to their clinical symptoms . Three were excluded for sickle-cell disease or poor nutritional status . None of the 110 strains (including 4 S . typhi, 51 S . typhimurium, 25 S . enteritidis, 6 S . hadar and 5 S . heidelberg) isolated was resistant to ceftriaxone or ciprofloxacin . Forty-one of the 110 strains (37.3%) produced a beta-lactamase . Twelve patients had a rapid recovery without antibiotic treatment, and 98 (mean age 3.9 years) were given antibiotics (ceftriaxone in 91 and amoxicillin in 7) for dysentery (43%), shock (15%) or persistent high fever and severe diarrhea (42%) . RESULTS: In 72 children (mean age = 3.6 years) ceftriaxone treatment (amoxicillin in 5) for 5 or 7 days was rapidly effective: apyrexia was obtained in 1.5 day after the start of treatment and the number of stools per day was 4 or less in 2.2 days . Two to 3 weeks after clinical recovery, asymptomatic carriage was present in 22/38 patients . In the 26 other patients ceftriaxone (amoxicillin in 2) treatment was clinically ineffective, despite good in vitro activity, and was switch for oral ciprofloxacin (20 mg kg(-1) d(-1), 5 days) after 2 to 7 days of lasted fever and/or severe diarrhea . Clinical improvement with ciprofloxacin was obtained in less than 48 h . The strains involved in these 26 patients included the 4 S . typhi and 15 S . typhimurium (P < 0.05), 13/15 (P < 0.01) producing beta-lactamase . Asymptomatic carriage was found in 5/22 patients (P < 0.05) after recovery . None of the patient treated with ciprofloxacin had side effect . CONCLUSION: In severe salmonellosis, the clinical failure of treatment with ceftriaxone is not rare, particularly in S . typhimurium producing beta-lactamase infection and short treatment with oral ciprofloxacin is safe and allows to obtain a rapid recovery. Microbiol Res, 2003, 158(2), 135 - 42 Typing of Salmonella enterica subsp . enterica serovars Choleraesuis, Typhimurium, Dublin and laboratory strains of Escherichia coli using subtracted restriction fingerprinting (SRF); Terletski V et al.; The aim of the present study was to evaluate the usefulness of a new typing technique called subtracted restriction fingerprinting (SRF) for bacterial strain and isolate discrimination . The technique was applied to isolates of Salmonella enterica subsp . enterica (S.) serovars Choleraesuis, Typhimurium, Dublin and to two laboratory strains of E . coli . SRF is based on the selective removal of excess fragments from a restriction digest using magnetic particles . Subsequently, the remaining subset of restriction fragments can easily be analyzed with a conventional agarose gel . Larger fragments are preferentially removed by SRF . This results in an even distribution of bands within each electrophoretic lane and significantly improves scoring . The high discriminatory index for (S.) Choleraesuis (D = 0.914) illustrated the suitability of SRF for genome typing. Clin Infect Dis, 2003 Aug 15, 37(4), e47 - 52 Epub 2003 Jul 29. Clinical review of nontyphoid Salmonella infections from 1991 to 1999 in a Danish county; Fisker N et al.; To determine outcomes of nontyphoid Salmonella infections, we reviewed all 3328 cases of infection registered in a large Danish county from 1991 to 1999 . The hospitalization rate was 27% among patients <5 years old, 22% among patients 5-59 years old, and 54% among patients > or =60 years old; complications were present in 7% and extraintestinal disease in 4% of patients . We conclude that nontyphoid Salmonella infections may frequently cause severe disease even among patients without predisposing conditions. Arch Microbiol, 2003 Oct, 180(4), 240 - 50 Epub 2003 Aug 07. Genetic analysis of phosphomannomutase/phosphoglucomutase from Vibrio furnissii and characterization of its role in virulence; Kim SH et al.; The pmm gene from Vibrio furnissii, which encodes phosphomannomutase (PMM), was cloned and sequenced . The open reading frame consisted of 1,434 bp, encoding a polypeptide of 477 amino acids with a molecular mass of 53,325 Da . The predicted amino acid sequence of V . furnissii PMM showed high similarity with PMMs from other enteric bacteria, such as V . cholerae, Salmonella sp . and Escherichia coli . The PMM protein was overexpressed in E . coli as a His(6)-tagged recombinant protein . The estimated apparent K(m )and k(cat) values of the purified recombinant protein for mannose 1-phosphate were about 60 microM and 800 min(-1), respectively . To investigate the biochemical functions and the role of pmm in the virulence of V . furnissii, a pmm knock-out mutant was constructed by homologous recombination mutation . Under the various physical conditions, cell numbers of the wild-type and the mutant did not differ . Oral introduction of bacterial suspensions to a mouse model showed that the pmm-deficient mutant decreased in viability at the intestine . Microscopy of the isolated intestines from mice revealed significant damage after 3 days in intestinal mucosa infected with the wild-type as compared with the mutant . The pmm-deficient mutant caused a reduction of virulence in mice and the loss of O-antigen polysaccharide, and showed low resistance relative to the wild-type when incubated with normal human serum. Microbiology, 2003 Aug, 149(Pt 8), 2015 - 21 Effect of EDTA on Salmonella enterica serovar Typhimurium involves a component not assignable to lipopolysaccharide release; Alakomi HL et al.; The effect of EDTA on Salmonella enterica serovar Typhimurium was studied in different growth phases with cells grown with or without Ca(2+) and Mg(2+) supplementation . EDTA affected the outer membrane much more strongly in the early exponential phase than in the mid- or late exponential phase, as indicated by uptake of 1-N-phenylnaphthylamine (a nonpolar hydrophobic probe, M(r) 219), and detergent (SDS) susceptibility . This effect was, however, not paralleled by LPS release (determined by measuring LPS-specific fatty acids or 14C-labelled LPS in cell-free supernatants, per a standardized cell density), which remained unchanged as a function of the growth curve . The conclusion from these results is that in the early exponential phase the effect of EDTA in S . enterica involves a component that is independent of LPS release. J Clin Microbiol, 2003 Aug, 41(8), 3823 - 8 Differences in gene content among Salmonella enterica serovar typhi isolates; Boyd EF et al.; We used a nonredundant microarray of the Salmonella enterica serovar Typhimurium LT2 and Typhi CT18 genomes to assess the genomic content of a diverse set of isolates of serovar Typhi . Comparative genomic hybridization revealed 13 regions of absent or divergent gene content in the eight Typhi strains examined compared to Typhi CT18 . In particular, two Typhi CT18 prophage regions, STY1048 to STY1077 and STY2038 to STY2077, as well as a five-gene islet (STY3188 to STY3193) were absent or divergent in all other Typhi strains examined . Seven Typhi strains lacked most or all of the IS1 elements present in strain CT18, and three Typhi strains lacked a P4-like phage (STY4821 to STY4834) . One strain was devoid of a 149-gene region (STY4521 to STY4680), which encodes numerous phage genes and the Vi antigen biosynthesis and export gene cluster, a type IV pilus, and numerous phage genes . In Typhi strain 26T25, an amplification of an entire inter-ribosomal region encompassing 31 genes has occurred . Furthermore, a 257-gene region (STY1360 to STY1639) showed an aberrant replication pattern in three Typhi isolates . Overall, these differences in gene content indicate that even within a highly clonal bacterial population the genomic reservoir is unstable. J Clin Microbiol, 2003 Aug, 41(8), 3574 - 8 Antimicrobial susceptibilities of salmonella strains isolated from humans, cattle, pigs, and chickens in the Netherlands from 1984 to 2001; van Duijkeren E et al.; We monitored antimicrobial susceptibility data for Salmonella strains isolated from humans, cattle, pigs, and chickens in The Netherlands from 1984 to 2001 in order to provide insight into the dynamics of resistance over time . The strains were tested for their susceptibilities to seven antimicrobial agents by the agar diffusion method . Resistance was most common in Salmonella enterica subsp . enterica serovar Typhimurium . Among the strains from humans, pigs, and chickens, it was found that the level of resistance of serovar Typhimurium strains to tetracycline, ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole increased from 1984 to 2001 . This increase could be attributed to the emergence of multidrug-resistant serovar Typhimurium DT 104 . Among the strains from cattle, it was found that the level of resistance of serovar Typhimurium strains, which was already very high in the 1980s, declined during the study period to the same levels as those for the strains from the other species from 1996 to 2001 . Serovar Enteritidis isolates remained susceptible during the entire survey period . Among serovar Paratyphi B variation Java strains isolated from chickens, resistance to furazolidone, flumequine, trimethoprim-sulfamethoxazole, and ampicillin emerged, although furazolidone was not used after 1990 . Together, the data indicate that the levels and patterns of resistance differed considerably between Salmonella serovars isolated from one host species.
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