Immunopharmacol Immunotoxicol, 2000 Aug, 22(3), 451 - 64 Evaluation of the natural immunity in pups inoculated with a modified-live canine parvovirus type 2b (CPV-2b) strain; Pratelli A et al.; Three pups 2-4 months old were vaccinated subcutaneously with the modified live canine parvovirus, CPV-2b/29-97 strain . During an observation period of two weeks pups remained clinically health, exhibiting a vigorous post-vaccinal active serological response (haemoagglutinating inhibiting antibody titers for CPV-2 ranging from 1:2560 to 1:5120 at 21 days post inoculation) . Phagocytosis and killing of Candida albicans exerted by polymorphonuclear cells and monocytes did not undergo significant modifications 3-6 days post vaccination up to 30 days . Antibacterial activity mediated by peripheral blood lymphocytes (Salmonella typhi was used as a target) was slightly, but not significantly decreased 3 days post vaccination . Conclusively, in pups the CPV type 2b vaccine seems to be safe as far as natural immune responses are concerned, while its immunogenicity is preserved. New Microbiol, 2000 Jan, 23(1), 11 - 20 Application of PFGE performed with XbaI to an epidemiological and phylogenetic study of Salmonella serotype typhimurium . Relations between genetic types and phage types; Guerra B et al.; PFGE performed with XbaI was evaluated and applied as a typing method in a series of 68 Salmonella serotype Typhimurium strains collected in a Spanish region throughout 1984-1994, and four reference strains . Using bands > 100 kb as a separation criterion, 26 pulsed-field profiles (PFPs) were defined, with a discrimination index of 0.87 . The XbaI-profiles were grouped into three clusters and two additional branches in a dendrogram of similarity (significance level = 0.7) . Strains belonging to PFP-X1 and PFP-X2 predominated (26.4% and 23.6%, respectively) and fell into the major cluster . The series had been previously analysed by phage typing and a three-way ribotyping procedure, and a certain degree of relation among the three methods was revealed, PFGE being the most discriminatory . Combining data from the three methods a further differentiation into 46 clonal lines was obtained, and four lines, at least, could be considered as endemic in the region under study . This procedure proved to be a powerful epidemiological tool for characterization of Typhimurium and in the investigation of outbreaks. Mutat Res, 2000 Aug 21, 469(1), 41 - 50 Chemical and mutagenic properties of asphalt fume condensates generated under laboratory and field conditions; Reinke G et al.; Exposure to asphalt fumes is widely recognized as a potential occupational health concern for paving and roofing workers . Two studies suggest that asphalt fumes generated in the laboratory are carcinogenic to mice . In this study, asphalt fume condensate (AFC) was collected from the head space of an operating hot mix asphalt storage tank and from a laboratory fume-generating apparatus operating at approximately 149 degrees C and 316 degrees C . Salmonella assays for mutagenesis, in vitro chromosomal aberration assays using Chinese hamster ovary (CHO) cells, chemical analyses, and simulated distillations were performed using gas chromatography to characterize the toxicological and chemical properties of AFCs generated by these two methods . The 316 degrees C lab AFC sample was more mutagenic in the Salmonella assay than the 149 degrees C lab AFC sample, with mutagenicity indices (MIs) of 8.3 and 5.3, respectively . AFCs collected from the storage tank were not mutagenic . Chromosomal aberration assays of all AFCs were negative . Chemical analyses and simulated distillations showed substantial differences in the chemical composition of the AFC samples . The 316 degrees C lab AFC sample contained more higher-boiling-point (three- and four-ring) polycyclic aromatic sulfur heterocycle compounds than the 149 degrees C lab AFC sample, and both lab AFC samples contained 5 to 100 times more of these compounds than AFC samples collected from the asphalt storage tank . These results are consistent with other data reported in the scientific literature describing the carcinogenicity of higher-boiling-point sulfur heterocycle compounds . In contrast to other recent studies, the results of this study indicate that the chemical composition and toxicological properties of laboratory-generated asphalt fumes are not representative of those properties of fumes to which workers and the public might be exposed. Vet Microbiol, 2000 Sep 25, 76(2), 185 - 92 Orally administered attenuated Salmonella enteritidis reduces chicken cecal carriage of virulent Salmonella challenge organisms; Cerquetti MC et al.; Chickens were immunized orally with 10(9)cfu of the temperature-sensitive (T(s)) mutant E/1/3 of Salmonella enteritidis at 1, 2, 3 and 7 days of age . The animals were challenged with wild-type strains of Salmonella of different serotypes 7 or 14 days following immunization . Chickens receiving multiple oral doses of the vaccine strain showed no signs of disease . Immunized animals shed the vaccine strain for at least 2 weeks after the last inoculation; on the other hand, colonization by the attenuated mutant of internal organs such as spleen and liver was limited . Early exposure of the immunized animals to the virulent bacteria resulted in a reduced cecal colonization by the pathogen . Visceral invasion by the wild-type strain of S . enteritidis or S . gallinarum was drastically diminished in birds challenged 14 days after immunization . Significant differences in the number of these Salmonella were found in the cecal contents, spleen and liver of immunized birds compared with the control animals . In addition, cecal colonization by the virulent strain was reduced in birds challenged with S . typhimurium . These results demonstrate that immunization of newly hatched chickens with live attenuated T(s) mutant E/1/3 of S . enteritidis is safe and reduces Salmonella shedding. Vet Microbiol, 2000 Sep 25, 76(2), 143 - 51 Prevalence of Salmonella in beef feeder steers as determined by bacterial culture and ELISA serology; Galland JC et al.; Results are presented for monitoring Salmonella infection by bacteriological culture and immune response (enzyme linked immunosorbent assay (ELISA) and haptoglobin) testing of samples collected from beef cattle at a single feedyard sampled over time . A total of 120 beef steers were examined on entry to the feedyard and at days 30, 60, and at time of slaughter (120-150 days) . Isolations of Salmonella decreased over time from 40% of the steers sampled at day 0 to 0% at slaughter, whereas serological results varied by serogroup . Seropositivity increased for Salmonella group B up to day 60, and subsequently decreased to about half of the 60-day positivity rate at the time of slaughter . No significant changes in seropositivity were detected during the course of the study for the four other Salmonella serogroups (C1, C3, D1, and E1) . Haptoglobin measurements were not a good indicator of Salmonella infection status . Sequential Salmonella testing either by culture, ELISA, or both could be used to monitor pathogen control practices. J Appl Microbiol, 2000 Jul, 89(1), 130 - 6 16S to 23S rRNA spacer fragment length polymorphism of Salmonella enterica at subspecies and serotype levels; Christensen H et al.; The variation in the lengths of the internal transcribed spacer (ITS) between 16S and 23S rRNA genes of 101 strains representing 58 serotypes of Salmonella enterica (used for Salm . choleraesuis) subsp . enterica (I), salamae (II), arizonae (IIIa), diarizonae (IIIb), houtenae (IV) and indica (VI) was used for typing by PCR amplification . Ten fragment lengths were observed by denaturing polyacrylamide gel electrophoresis on an automatic DNA sequencer resulting in 21 unique fragment patterns . Ten out of the 58 serotypes showed specific patterns but 48 serotypes were not fully differentiated . More than one ITS pattern was observed in seven serotypes . Five of the 21 fragment patterns contained representatives of more than one subspecies . Under non-denaturing electrophoresis conditions, serotype specificity was obtained but precise ITS fragment length determination was not possible . DNA sequence comparison between ITSs of individual rrn operons is needed to further interpret ITS diversity within Salm . enterica at serotype and subspecies levels. J Food Prot, 2000 Aug, 63(8), 1144 - 53 Microbiological safety of mayonnaise, salad dressings, and sauces produced in the United States: a review; Smittle RB; The literature on the death and survival of foodborne pathogens in commercial mayonnaise, dressing, and sauces was reviewed and statistically analyzed with emphasis on Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes . The absence of reports of foodborne illness associated directly with the consumption of commercially prepared acidic dressings and sauces is evidence of their safety . Salmonella, E . coli O157:H7, E . coli, L . monocytogenes, Staphylococcus aureus, and Yersinia enterocolitica die when inoculated into mayonnaise and dressings . Historically, mayonnaise and dressings have been exempt from the acidified food regulations and have justly deserved this status due primarily to the toxic effect of acetic and to a lesser extent lactic and citric acids . These organic acids are inimical to pathogenic bacteria and are effective natural preservatives with acetic being the most effective in killing pathogenic bacteria at the pH values encountered in these products . Statistical analysis on data reported in the literature shows that the most important and significant factor in destroying pathogenic bacteria is pH as adjusted with acetic acid followed by the concentration of acetic acid in the water phase . The reported highest manufacturing target pH for dressings and sauces is 4.4, which is below the 4.75 pKa of acetic acid and below the reported inhibitory pH of 4.5 for foodborne pathogens in the presence of acetic acid . The overall conclusion is that these products are very safe . They should remain exempt from the acidified food regulations providing adequate research has been done to validate their safety, and the predominant acid is acetic and reasonable manufacturing precautions are taken. J Food Prot, 2000 Aug, 63(8), 1113 - 6 Recalls of foods and cosmetics due to microbial contamination reported to the U.S . Food and Drug Administration; Wong S et al.; In the U.S., food product recalls serve as an important intervention in stemming the consumption of food products contaminated with infectious disease agents . We summarize the number and nature of foods and cosmetics recalled as a result of microbial contamination reported to the U.S . Food and Drug Administration (FDA) for the period 1 October 1993 through 30 September 1998 . During this period, microbial contamination of food and cosmetic products was the leading cause for recalls, accounting for a total of 1,370 recalls (36% of all products recalled) . Listeria monocytogenes accounted for the greatest number of food products recalled because of microbial contamination, whereas Pseudomonas aeruginosa was the most common microbe associated with recalls of cosmetic products . Dairy products, followed by seafood and pastry items, were the types of products most often associated with recalls due to microbial contamination . The FDA was the entity most often responsible for detecting microbial contamination of foods and cosmetics (33% of all such recalls), followed by state regulatory agencies (24%), and manufacturers/retailers (21%) . Nineteen percent of recalls were associated with at least one reported case of illness . Salmonella was the pathogen most often implicated in reports of illness associated with these recalled products. J Food Prot, 2000 Aug, 63(8), 1053 - 7 Survival of Yersinia enterocolitica and mesophilic aerobic bacteria on eggshell after washing with hypochlorite and organic acid solutions; Favier GI et al.; Populations of Yersinia enterocolitica 0:9 and mesophilic aerobic bacteria on the shell of fresh chicken eggs were assessed prior and after washing with 0.75%, 1%, and 3% acetic and lactic acids, 50, 100, and 200 mg/liter (ppm) of chlorine, and water . Highest reductions of mesophilic aerobic bacterial populations (normal flora) on trypticase soy agar were 1.28 and 2.15 log10 cycles with 100 and 200 mg/liter of chlorine, 0.28 and 0.36 log10 cycles with 1% and 3% acetic acid, and 0.70 and 0.71 log10 cycles with 1% and 3% lactic acid, respectively, as compared to the control group . No Salmonella or Yersinia were detected among the natural flora of the eggs . On Y . enterocolitica O:9-inoculated eggs, reductions of 2.66, 2.77, and 2.92 log10 cycles by 50, 100, and 200 mg/liter of chlorine, of 2.47, 2.48, and 2.49 log10 cycles by 0.75%, 1%, and 3% of acetic acid, and of 2.48 and 2.72 log10 cycles with 1% and 3% of lactic acid, respectively, were observed with respect to the control . Organic acids at 3% caused detachment of the surface cuticle of the eggshell . Y . enterocolitica was more sensitive to the wash treatments than the natural microflora . The absence of potentially pathogenic Y . enterocolitica, observed for other fresh foods, should be a norm for fresh eggs sold in retail stores. J Vet Med Sci, 2000 Jul, 62(7), 789 - 91 Salmonella contamination in commercial layer feed in Japan; Shirota K et al.; A total of 4,418 samples of commercial layer feeds obtained in 1998 were investigated for the presence of salmonellae . A total of 146 strains of salmonellae which consisted of 32 serovars, including 20 strains of Salmonella Enteritidis, were isolated from 143 feed samples. J Vet Med Sci, 2000 Jul, 62(7), 767 - 9 Salmonella virchow infection in an infant transmitted by household dogs; Sato Y et al.; A 4-month-old male infant manifested diarrhea and Salmonella Virchow was isolated from his stool . The pathogen was repeatedly isolated from the infant over one month despite three regimens of treatment with antibiotics, to which the isolate was sensitive . Three household dogs were kept in his home and S . Virchow was isolated from two of them . The infant was admitted to hospital and was treated with antibiotic, then the pathogen was finally eliminated . Antibiotic sensitivity pattern and PFGE pattern produced by restriction enzyme Xba I of the isolate from the infant was completely similar to those of the isolates from the dogs . The above findings indicated that the present S . Virchow infection in the infant was transmitted by the household dogs. East Afr Med J, 2000 Jan, 77(1), 23 - 6 Chronic osteomyelitis in patients with sickle cell disease; Nwadiaro HC et al.; OBJECTIVE: To determine the baseline pattern and audit management modalities of chronic osteomyelitis in patients with sickle cell disease . DESIGN: A retrospective study . SETTING: Jos University Teaching Hospital, Jos, Nigeria from August 1993 to July 1997 . PATIENTS: Twenty four patients with concomitant chronic sickle cell disease . INTERVENTIONS: Fifteen patients had operations; eleven had sequestrectomy and curettage while four had incision and drainage . Eight patients were treated with antibiotics alone and one patient refused surgery . MAIN OUTCOME MEASURES: The demographic data of patients, aetiological agents, culture and sensitivity patterns, aetiopathogenesis, treatment modalities and outcome were analysed . RESULTS: Twenty four (36.9%) out of 65 patients who had chronic osteomyelitis also had sickle cell disease . Male:female ratio was 1.2:1 . The peak age incidence (37.5%) was in the first decade of life . Seventy five per cent of infections were haematogenous . The most frequently isolated organism was Staphylococcus aureus (58.8%) while the rest were Gram negative organisms . There was no case of Salmonella osteomyelitis . The most sensitive antibiotics were gentamicin and the third generation cephalosporins . Twelve patients (50%) had good results while eight (33.3%) were still undergoing treatment . Complications recorded were persistent discharging sinuses in two cases, recurrence of symptoms in one and pathological fracture with non-union in one patient . CONCLUSION: Though the incidence of Gram negative organisms in causation of chronic osteomyelitis in patients who have sickle cell disease is high (41.2%), Salmonella osteomyelitis may be related to endemicity of the organism in a given locality. Microbiol Immunol, 2000, 44(6), 473 - 9 Blockade of Salmonella enteritidis passage across the basolateral barriers of human intestinal epithelial cells by specific antibody; Sugita-Konishi Y et al.; Antibodies specific to Salmonella enteritidis (S.E.) were obtained from immunized egg yolk, and their protective effects against S.E . were studied by using monolayer-cultured human intestinal epithelial cells, Caco-2 and T84 . The Salmonella adherence and entry to the cells were partially inhibited by the antibodies . The antibodies inhibited the decrease in transepithelial electrical resistance (TEER) of the intestinal epithelial monolayers and IL-8 secretion of the cells induced by S.E . invasion . Also, the antibodies blocked the penetration of bacteria through the cell layer although they did not inhibit the growth of bacteria in the cells . Confocal microscopic photographs revealed the bacteria in the infected monolayer cells were bound to antibodies . These results indicate that anti-S.E . antibodies may protect the cells from destruction induced by S.E . invasion in intestinal epithelial cells in addition to the partial inhibition of adhesion and invasion of S.E . at the cell surface . Passive antibodies against invasive bacteria would be useful to prevent the migration of S.E . to blood not only at the cell surface but also inside of intestinal epithelial cells. Ned Tijdschr Geneeskd, 2000 Jul 29, 144(31), 1480 - 4 {Clinical thinking and decision making in practice . A patient with persistent fever}; Koopmans RP et al.; A 20-year old man was admitted to hospital with fever and malaise after travel to India . He was soon found to have typhoid fever, caused by a multi-drug resistant Salmonella typhi . According to in-vitro resistance testing he was treated with cefotaxim, but fever and shivering were still present after 7 days of cefotaxim, with liver enzyme disturbances . The physicians caring for him started an extensive search for possible complications of typhoid fever, and they thought of the possibility of an alternative disease to explain the fever . When cefotaxim was stopped all symptoms and signs disappeared . During every medication, drug fever is a possibility . This diagnosis can only be supported by discontinuing the use and if necessary, restarting it (dechallenge and rechallenge). J Bacteriol, 2000 Sep, 182(17), 4906 - 14 Domain structure of Salmonella FlhB, a flagellar export component responsible for substrate specificity switching; Minamino T et al.; We have investigated the properties of the cytoplasmic domain (FlhB(C)) of the 383-amino-acid Salmonella membrane protein FlhB, a component of the type III flagellar export apparatus . FlhB, along with the hook-length control protein FliK, mediates the switching of export specificity from rod- and hook-type substrates to filament-type substrates during flagellar morphogenesis . Wild-type FlhB(C) was unstable (half-life, ca . 5 min), being specifically cleaved at Pro-270 into two polypeptides, FlhB(CN) and FlhB(CC), which retained the ability to interact with each other after cleavage . Full-length wild-type FlhB was also subject to cleavage . Coproduction of the cleavage products, FlhB(delta CC) (i.e., the N-terminal transmembrane domain FlhB(TM) plus FlhB(CN)) and FlhB(CC), resulted in restoration of both motility and flagellar protein export to an flhB mutant host, indicating that the two polypeptides were capable of productive association . Mutant FlhB proteins that can undergo switching of substrate specificity even in the absence of FliK were much more resistant to cleavage (half-lives, 20 to 60 min) . The cleavage products of wild-type FlhB(C), existing as a FlhB(CN)-FlhB(CC) complex on an affinity blot membrane, bound the rod- and hook-type substrate FlgD more strongly than the filament-type substrate FliC . In contrast, the intact form of FlhB(C) (mutant or wild type) or the FlhB(CC) polypeptide alone bound FlgD and FliC to about the same extent . FlhB(CN) by itself did not bind substrates appreciably . We propose that FlhB(C) has two substrate specificity states and that a conformational change, mediated by the interaction between FlhB(CN) and FlhB(CC), is responsible for the specificity switching process . FliK itself is an export substrate; its binding properties for FlhB(C) resemble those of FlgD and do not provide any evidence for a physical interaction beyond that of the export process. Int J Syst Evol Microbiol, 2000 Jul, 50 Pt 4, 1693 - 4 Arguments against the replacement of type species of the genus Salmonella from Salmonella choleraesuis to 'Salmonella enterica' and the creation of the term 'neotype species', and for conservation of Salmonella choleraesuis; Yabuuchi E et al.; The proposals of Le Minor and Popoff in 1987 and again of Euzeby in 1999 on the type species of the genus Salmonella are in violation of Rule 20a of the Bacteriological Code (1990 Revision) and should be rejected . The introduction of the term 'neotype species' should be rejected . The specific epithet choleraesuis in the binary combination Salmonella choleraesuis should be conserved . The serovar name Choleraesuis should be changed to Hogcholera. Indian J Med Res, 2000 Mar, 111, 75 - 6 Occurrence of Salmonella typhi infection in Rourkela, Orissa; Bhattacharya SS et al.; Between January 1996 and December 1998, the isolation rate of Salmonella typhi in Rourkela was found to be on a steady rise . Of the 7866 samples (blood and bone marrow) tested, 988 were found positive for S . typhi giving an overall per cent positivity of 12.56 . Enteric fever was found to occur almost throughout the year with a peak from early winter up to the end of summer . In this study, chloramphenicol was found to have an average sensitivity of 87.46 per cent . Ceftriaxone showed 100 per cent sensitivity. Turk J Pediatr, 2000 Apr-Jun, 42(2), 151 - 4 Salmonella septic arthritis in a patient with acute idiopathic thrombocytopenic purpura treated with steroid; Kanra G et al.; Salmonella has three clinical presentations: self-limiting gastroenteritis, a systemic syndrome (enteric or typhoid fever), and bacteremia with focal infection . Hematogenous infections can cause focal lesions, but unusual manifestations occur more often when predisposing factors such as T cell defect, hemolytic disorders (sickle cell disease, malaria) or trauma are present . Salmonella tend to invade bones and joints . There is no mention of acute idiopathic (immune) thrombocytopenic purpura as a predisposing factor for salmonella septic arthritis; however there are reports about the importance of platelets for the immune response . Here we present a case of Salmonella enteritidis septic arthritis following acute idiopathic (immune) thrombocytopenic purpura in a 15-year-old female patient who has been on steroid therapy for the last two weeks. Chem Biol Interact, 2000 Jul 3, 127(2), 163 - 80 Genotoxic effects of allyl isothiocyanate (AITC) and phenethyl isothiocyanate (PEITC); Kassie F et al.; Two isothiocyanates (ITCs) commonly found in human diet, allyl isothiocyanate (AITC) and phenethyl isothiocyanate (PEITC), were tested for genotoxic effects in a battery of assays: Salmonella/microsome assay with TA 98 and TA 100, differential DNA repair assay with E . coli and micronucleus (MN) induction assay with human derived Hep G2 cells . Albeit to a different degree, both ITCs induced genotoxic effects in all test systems . AITC was more genotoxic in bacterial test systems than in Hep G2 cells; in contrast, the effect of PEITC was stronger in Hep G2 cells . In in vivo assays with E . coli indicators in which mice were exposed to relatively high doses of the compounds (90 and 270 mg/kg), AITC induced moderate but significant effects; PEITC failed to induce significant effects in any of the organs . To find out the reason for the weak genotoxicity of AITC and PEITC under in vivo test conditions, we exposed E . coli indicator cells to the test substances in the absence or presence of rat liver homogenate (with and without cofactors), bovine serum albumin (BSA) and human saliva . All of them markedly attenuated the genotoxicity of AITC and PEITC, implying that the test substances are detoxified by direct non-enzymatic binding to proteins . Additional experiments carried out on the mechanistic aspects of AITC and PEITC-induced genotoxicity showed that the compounds induce the formation of thiobarbituric acid reactive substances (TBARS) in Hep G2 cells . Furthermore, in in vitro assays with E . coli, radical scavengers reduced the differential DNA damage induced by AITC and PEITC . The latter two findings give a clue that reactive oxygen species might be involved in the genotoxic effect of the ITCs . Although ITCs have been repeatedly advocated as very promising anticancer agents, the data presented here indicate that the compounds are genotoxic, and probably carcinogenic, in their own right. Rev Sci Tech, 2000 Aug, 19(2), 405 - 24 Fowl typhoid and pullorum disease; Shivaprasad HL; Fowl typhoid (FT) and pullorum disease (PD) are septicaemic diseases, primarily of chickens and turkeys, caused by Gram negative bacteria, Salmonella Gallinarum and S . Pullorum, respectively . Clinical signs in chicks and poults include anorexia, diarrhoea, dehydration, weakness and high mortality . In mature fowl, FT and PD are manifested by decreased egg production, fertility, hatchability and anorexia, and increased mortality . Gross and microscopic lesions due to FT and PD in chicks and poults include hepatitis, splenitis, typhlitis, omphalitis, myocarditis, ventriculitis, pneumonia, synovitis, peritonitis and ophthalmitis . In mature fowl, lesions include oophoritis, salpingitis, orchitis, peritonitis and perihepatitis . Transovarian infection resulting in infection of the egg and subsequently the chick or poult is one of the most important modes of transmission of these two diseases . Salmonella Gallinarum and S . Pullorum can be isolated by use of selective and non-selective media . Salmonella Pullorum produces rapid decarboxylation of ornithine whereas S . Gallinarum does not, an important biochemical difference between the two bacteria . Both FT and PD can be detected serologically by use of a macroscopic tube agglutination test, rapid serum test, stained antigen whole blood test or microagglutination test . Both diseases can be controlled and eradicated by use of serological testing and elimination of positive birds . Vaccines may be used to control the disease and antibiotics for the treatment of FT and PD . Although FT and PD are widely distributed throughout the world, the diseases have been eradicated from commercial poultry in developed countries such as the United States of America, Canada and most countries of Western Europe . Both S . Gallinarum and S . Pullorum are highly adapted to the host species, and therefore are of little public health significance. Rev Sci Tech, 2000 Aug, 19(2), 351 - 75 The paratyphoid salmonellae; Barrow PA; The paratyphoid Salmonella bacteria, comprising more than 2,000 serovars or serotypes, are a major problem to the poultry industry . This is largely the result of entry of the bacteria into the human food chain . Human infection takes the form of a gastroenteritis, which in highly susceptible individuals can result in death . Some strains of certain serotypes have the capacity to produce morbidity and mortality in very young chickens . In adult birds, some serovars become localised in the reproductive tract with concomitant vertical transmission . The association between S . Enteritidis and table eggs has produced a great deal of publicity and concern with resulting national and international attempts at controlling the major serotypes, S . Typhimurium and S . Enteritidis, at the breeder and layer level . Control is possible through rigorous hygiene and management procedures, but is not always economically viable . As a result, control by serological and bacteriological testing and slaughter may also not be feasible . Antibiotics have been used to reduce carriage but can cause problems of resistance and increased susceptibility . The use of growth promoting antibiotics can also increase susceptibility to infection . Other means of increasing the resistance of poultry to infection are therefore being sought . These include the use of intestinal flora preparations for competitive exclusion of Salmonella from newly hatched chicks . Killed and live vaccines are used, both with some success . However, the safety of some live vaccines is still uncertain. J Med Microbiol, 2000 Aug, 49(8), 691 - 6 Adhesion of Salmonella enterica var Enteritidis strains lacking fimbriae and flagella to rat ileal explants cultured at the air interface or submerged in tissue culture medium; Robertson JM et al.; Rat ileal air interface and submerged explant models were developed and used to compare the adhesion of Salmonella enterica var Enteritidis wild-type strains with that of their isogenic single and multiple deletion mutants . The modified strains studied were defective for fimbriae, flagella, motility or chemotaxis and binding was assessed on tissues with and without an intact mucus layer . A multiple afimbriate/aflagellate (fim-/fla-) strain, a fimbriate but aflagellate (fla-) strain and a fimbriate/flagellate but non-motile (mot-) strain bound significantly less extensively to the explants than the corresponding wild-type strains . With the submerged explant model this difference was evident in tissues with or without a mucus layer, whereas in the air interface model it was observed only in tissues with an intact mucus layer . A smooth swimming chemotaxis-defective (che-) strain and single or multiple afimbriate strains bound to explants as well as their corresponding wild-type strain . This suggests that under the present experimental conditions fimbriae were not essential for attachment of S . enterica var Enteritidis to rat ileal explants . However, the possession of active flagella did appear to be an important factor in enabling salmonellae to penetrate the gastrointestinal mucus layer and attach specifically to epithelial cells. Rev Latinoam Microbiol, 1999 Jul-Sep, 41(3), 121 - 6 {Antimicrobial resistance among species of Salmonella, Shigella, Escherichia, and aeromonas isolated from children with diarrhea in 7 Argentinian centers}; Binsztein N et al.; The increasing levels of resistance of enteropathogenic bacteria against antimicrobial agents present geographic variations . We have analysed the antimicrobial susceptibility of isolates obtained from 4,364 children under 5 years of age with acute diarrhea, in 7 cities of Argentina . Diarrheagenic E . coli exhibited 74.5% of resistance against ampicillin, 64.2% against sulfametoxazole-trimethoprim, and Shigella spp., 62% and 75.6% respectively . Salmonella sp . showed 35%, 14%, 41.8%, 65.4%, 14.5%, and 13.6% of resistance against ampicillin, chloranfenicol, sulfametoxazole-trimetoprim, sulfadiazin, gentamycin, and fosfomycin respectively . These values are higher than the ones observed in developed countries . Aeromonas showed significantly lower resistance percentage . Important differences in our country were observed, consequently, local trials should be carried out in order to apply corrective measures. Mol Microbiol, 2000 Jul, 37(2), 300 - 15 The cis requirements for transcriptional activation by HilA, a virulence determinant encoded on SPI-1; Lostroh CP et al.; In several models of pathogenesis, Salmonella requires genes encoded on Salmonella pathogenicity island 1 (SPI-1) for virulence . In Salmonella enterica serovar Typhimurium (S . typhimurium), most SPI-1 genes are arranged in operons and are co-ordinately regulated in response to environmental signals via the SPI-1-encoded protein HilA . In order to understand how HilA controls the transcription of SPI-1 genes, we have analysed the invF and prgH promoters . We have reconstituted HilA-dependent activation of both promoters in Escherichia coli by supplying hilA on a plasmid, strongly suggesting that HilA acts directly on the promoters . By analysing the HilA-dependent activity of deletions and mutations in PinvF, we identified cis elements necessary for HilA-dependent activation . Through biochemical studies, we have defined a probable HilA-binding sequence in the invF promoter . This 'HilA box' is intact in the minimal promoter identified through deletion analysis, and it is disrupted in one class of PinvF mutants that has reduced activation by HilA . The prgH promoter also contains a HilA box in the same position relative to the +1 of transcription . This work is the first to connect HilA-dependent environmental regulation with a specific sequence in a SPI-1 virulence gene promoter. Eur J Biochem, 2000 Aug, 267(16), 5023 - 31 Hadrurin, a new antimicrobial peptide from the venom of the scorpion Hadrurus aztecus; Torres-Larios A et al.; A new antimicrobial peptide, hadrurin, was isolated from the venom of the Mexican scorpion Hadrurus aztecus, by gel filtration on a Sephadex G-50 column, followed by high performance liquid chromatography . It is a basic peptide composed of 41 amino-acid residues with a molecular mass of 4436 Da, and contains no cysteines . A model of the three-dimensional folding of hadrurin is compatible with that of an amphipatic molecule with two alpha-helical segments . Hadrurin demonstrates antimicrobial activity at low micromolar concentration, inhibiting the growth of bacteria such as: Salmonella thyphi, Klebsiella pneumoniae, Enterococcus cloacae, Pseudomonas aeruginosa, Escherichia coli and Serratia marscences . It also shows cytolytic activity when tested in human erythrocytes . Hadrurin and two analogs (C-terminal amidated, and all D-enantiomer) were chemically synthesized . They were used to study the possible molecular mechanism of action by testing their ability to dissipate the diffusion potential of liposomes of different compositions . The results obtained indicate that there are no specific receptor molecules for the action of hadrurin, and the most probable mechanism is through a membrane destabilization activity . It is surmised that hadrurin is used by the scorpion as both an attack and defense element against its prey and putative invasive microorganisms . It is a unique peptide among all known antimicrobial peptides described, only partially similar to the N-terminal segment of gaegurin 4 and brevinin 2e, isolated from frog skin . It would certainly be a model molecule for studying new antibiotic activities and peptide-lipid interactions. FEMS Microbiol Lett, 2000 Aug 15, 189(2), 285 - 91 Partial characterization of a genomic island associated with the multidrug resistance region of Salmonella enterica Typhymurium DT104; Boyd DA et al.; This study describes the identification of the insertion site and partial characterization of a 43-kb region harboring the genes associated with the penta-resistant phenotype of a Canadian isolate of Salmonella enterica Typhymurium DT104 labelled 96-5227 . The 43-kb fragment, here referred to as Salmonella genomic island I (SgiI), was found in the genome of S . enterica Typhymurium between the thdf and a prophage CP-4-like integrase (int2) gene and is flanked by an imperfect 18-bp direct repeat . A region downstream of sulI in the right end of SgiI contained four open reading frames which includes an IS6100 element, and a 2-kb region from the left end contained two open reading frames which showed homology to an integrase and an excisionase . Furthermore, a 1.9-kb retron sequence located between int2 and yidY was identified which may be unique to the S . enterica Typhymurium genome . The int-retron sequence is flanked by a 27-bp imperfect direct repeat. Z Naturforsch {C}, 2000 May-Jun, 55(5-6), 489 - 93 Prevalence of multi-drug resistant Salmonella typhi among clinically diagnosed typhoid fever patients in Lagos, Nigeria; Akinyemi KO et al.; A total of 635 clinically diagnosed typhoid fever patients were bled from three different health institutions in the metropolis of Lagos, Nigeria over a period of 15 months, May 1997 to July 1998 . Out of the total blood cultured, 101 (15.9%) isolates of Salmonella species were isolated of which 68 (67.3%) were S . typhi, 17 (16.8%) and 16 (15.8%) were S . paratyphi A . and S . arizonae respectively . The overall isolation rate of S . typhi among patients is 10.7%, with most isolates 45.9% found among the severely-ill young adults, age group 16-30 years . All isolates were subjected to anti-microbial susceptibility testing using 12 different antibiotics: chloramphenicol, ampicillin, cotrimoxazole, gentamicin, colistin sulfate, nalidixic acid, nitrofurantoin, cefotaxime, tetracycline, streptomycin, ofloxacin and ciprofloxacin . All the S . typhi and S . paratyphi A isolates showed resistance to two or more of the 10 of 12 antibiotics tested particularly the 3-first-line antibiotics commonly used (chloramphenicol, ampicillin and cotrimoxazole) in the treatment of typhoid fever in Nigeria . No isolate showed resistance to ofloxacin and ciprofloxacin, however, nalidixic acid and gentamicin showed a moderate and appreciable inhibition to most of our isolates. Southeast Asian J Trop Med Public Health, 1999 Dec, 30(4), 776 - 8 Incidence of new Salmonella serovar (S . ratchaburi) in Thailand; Bangtrakulnonth A et al.; Eighteen strains of Salmonella group E from stool samples were confirmed as Salmonella new serovar . 3, 10 : Z35 : 1, 6 by Centre International des Salmonella, Institut Pasteur, Paris, WHO Collaborating Center for Salmonella, Atlanta, USA and Salmonella-Zentrale Hygienischen Institut, Hamburg, Germany . The name of this new serovar was proposed as S . ratchaburi according to the place of its first isolation in Ratchaburi province . The new serovar of Salmonella was sensitive to many antimicrobial agents except streptomycin and erythromycin. Southeast Asian J Trop Med Public Health, 1999 Dec, 30(4), 764 - 9 Comparison of the efficacy of ceftibuten and norfloxacin in the treatment of acute gastrointestinal infection in children; Moolasart P et al.; A prospective randomized study was conducted at an infectious disease hospital in Thailand . Ceftibuten was compared with norfloxacin, both given orally for five days for treatment of acute gastroenteritis in children . One hundred and seventy cases were included in the study . Eighty-eight cases were treated with ceftibuten and eighty-two cases with norfloxacin . The baseline characteristics of the patients in both treatment groups were similar . The results showed that mean durations of diarrhea in the ceftibuten and norfloxacin groups were 2.48 days and 2.29 days, respectively, but there was no statistically significant difference between the two groups (p > 0.05) . There were Salmonella spp and Shigella spp isolated in both treatment groups and all were susceptible to both antibiotics . The mean durations of Salmonella diarrhea in the ceftibuten and norfloxacin groups were 2.7 and 2.2 days, respectively, while those of Shigella diarrhea were 2.3 days and 2.0 days, respectively . There were no statistically significant differences in either comparison (p > 0.05) . Neither complications nor clinical relapses were observed after both antibiotics' treatment. Acta Paediatr Taiwan, 1999 Nov-Dec, 40(6), 430 - 3 Characterization of group D1 non-typhoid Salmonella isolates by serotyping and pulsed field gel electrophoresis; Li WC et al.; Non-typhoid salmonella infection is not uncommon in immunocompetent patients in Taiwan . Bacterial factors may play an important role in the pathogenesis of such infections . In a previous study, Salmonella group D1 was found to have the tendency to cause bacteremia with a higher frequency than other serotypes . In the present study, we prospectively collected 94 Salmonella group D1 isolates for serotyping and molecular typing . Salmonella panama and Salmonella dublin seemed more invasive than other serotypes . Pulsed field gel electrophoresis was also done to characterize of Salmonella enteritidis and Salmonella dublin . PFGE type "a" of Salmonella dublin appeared to be more invasive than the other two PFGE types . All six Salmonella dublin isolates were Vi antigen negative . Further study using a larger number of isolates is needed to identify the tendency to invade blood stream of Salmonella dublin and Salmonella panama. Berl Munch Tierarztl Wochenschr, 2000 Jun, 113(6), 246 - 52 {A new live Salmonella enteritidis vaccine for chickens--experimental evidence of its safety and efficacy}; Springer S et al.; Within the works for the registration of a new live Salmonella Enteritidis vaccine for layers, safety and efficacy of the vaccine strain were tested by experimental studies . After oral administration of the single and the tenfold dose, no incompatibility reactions were seen in day-old chicks . The laying performance and the egg weight were not affected by the vaccination of the chickens during the laying period . There was only a limited period in which the excretion of the vaccine strain and its persistency in organs were seen . Even after the threefold oral vaccination the vaccine strain could not be isolated from eggs and internal organs of slaughtered chickens . Moreover, a high safety for non-target animals (cattle, pigs) could be established . Studies with BALB/c mice proved that a cell-mediated immunity and the development of complement-fixing antibodies is induced by the vaccine . Efficacy studies in target animals were carried out by a proved dependable oral challenge system that reproduces a latent infection with marked S . Enteritidis strains and by means of the seeder-bird method . The test results demonstrate that the vaccination is capable to avert or to reduce an infection significantly. Berl Munch Tierarztl Wochenschr, 2000 Jun, 113(6), 225 - 33 {Results of the German investigation in the EU Project "Salmonella in Pork (Salinpork)"--2 . Investigations in a slaughterhouse}; von Altrock A et al.; In 1997 bacteriological examinations for the distribution of Salmonella in slaughterhouses were carried out in Germany within the framework of an international study "Salmonella in Pork (Salinpork)" . During 6 days, 1,200 swab and water samples from slaughtered pigs and the environment were taken . 4.4% of the samples (n = 53) were Salmonella positive . S . typhimurium was isolated mainly (69.8%; n = 37), and 6 phagetypes were differentiated . In addition, S . derby and S . panama could be demonstrated . The resistance pattern of the different isolated S . typhimurium-phagetypes are presented . The phagetype DT 104 was multiresistant to ampicillin, spectinomycin, streptomycin, sulphonamide and tetracycline . In comparison with the serological prevalence of 7.3% of the fattening pigs in the farms (Part 1), only 1.0% of the samples taken from the surface of the carcass were Salmonella-positive . Swabs taken from the liver were in 2.7% positive and samples from the tongue gave in 5.3% of the cases Salmonella-positive results . In the examination of the environment Salmonella was demonstrated mainly from the water outlets, whereas Salmonella could not be isolated from water of the scalding tank . There was only one case (0.7%) in which Salmonella could be isolated from the hands of the personnel, and also only one swab of the polishing machine was positive (1.1%) . But 6.7% samples of the saw were Salmonella-positive . A comparison of repeated, at intervals taken samples showed that the number of Salmonella-positive samples was higher in the last examination round of the particular slaughter days . The reason is suspected in the increasing number of slaughtered pigs and supplying farms, which may increase the probability of bringing in Salmonella. Vet Microbiol, 2000 Sep 15, 76(1), 61 - 9 Strain discrimination of a novel serotype of Salmonella from harbour porpoises (Phocoena phocoena) by molecular techniques; Crichton PB et al.; The relatedness of 41 isolates of Salmonella of a novel serotype (antigenic formula 4,12:a:-) of serogroup B, obtained from harbour porpoises (Phocoena phocoena) stranded at various sites around the coastline of Scotland, was assessed by two molecular typing methods . Ribotyping showed that these isolates belonged to seven EcoRI (E) ribotypes and 11 PstI (P) ribotypes that were, in each case, distinct but closely related . Combined ribotyping data identified 15 different E/P ribotypes, the most common of which, E1/P1, was represented by 15 isolates from 14 animals stranded on both east and west coastlines . Strain discrimination achieved by E/P ribotyping was high (D=0.84) . IS200 profiling revealed only three different fingerprints and strain discrimination by this method alone was poor (D=0.39) . When E/P ribotyping and IS200 profiling were used together, they revealed the existence of 17 different types among the 41 isolates which formed two distinct, but related, groups of Salmonella serotype 4,12:a:- . This information should prove helpful in future studies examining the mode of transmission of this novel salmonella serotype and its association with disease in harbour porpoises. Int J Epidemiol, 2000 Aug, 29(4), 730 - 3 Have lessons been learned from the UK bovine spongiform encephalopathy (BSE) epidemic? O'Brien M. History is full of examples of public health, commerce and politics in conflict . In recent years attempts to protect UK egg producers, after the discovery of Salmonella enteritidis (phage type 4) in hens' eggs, strained previously good working relationships between medical and veterinary epidemiologists and ended the political career of a government minister who spoke out in defence of the public health . Against the background lessons of earlier high profile public health problems in the UK conflict should have been avoided when bovine spongiform encephalopathy (BSE) started . It might have been expected that its significance for human health could have been recognized and researched earlier . Public announcements about it could have been timely and clear . Unfortunately this was not the case and it looks as though similar mistakes are going to be repeated over genetically modified foods. Proc Natl Acad Sci U S A, 2000 Aug 1, 97(16), 8822 - 8 Role of the cystic fibrosis transmembrane conductance regulator in innate immunity to Pseudomonas aeruginosa infections; Pier GB; Chronic Pseudomonas aeruginosa infection occurs in 75-90% of patients with cystic fibrosis (CF) . It is the foremost factor in pulmonary function decline and early mortality . A connection has been made between mutant or missing CF transmembrane conductance regulator (CFTR) in lung epithelial cell membranes and a failure in innate immunity leading to initiation of P . aeruginosa infection . Epithelial cells use CFTR as a receptor for internalization of P . aeruginosa via endocytosis and subsequent removal of bacteria from the airway . In the absence of functional CFTR, this interaction does not occur, allowing for increased bacterial loads in the lungs . Binding occurs between the outer core of the bacterial lipopolysaccharide and amino acids 108-117 in the first predicted extracellular domain of CFTR . In experimentally infected mice, inhibiting CFTR-mediated endocytosis of P . aeruginosa by inclusion in the bacterial inoculum of either free bacterial lipopolysaccharide or CFTR peptide 108-117 resulted in increased bacterial counts in the lungs . CFTR is also a receptor on gastrointestinal epithelial cells for Salmonella enterica serovar Typhi, the etiologic agent of typhoid fever . There was a significant decrease in translocation of this organism to the gastrointestinal submucosa in transgenic mice that are heterozygous carriers of a mutant DeltaF508 CFTR allele, suggesting heterozygous CFTR carriers may have increased resistance to typhoid fever . The identification of CFTR as a receptor for bacterial pathogens could underlie the biology of CF lung disease and be the basis for the heterozygote advantage for carriers of mutant alleles of CFTR. Proc Natl Acad Sci U S A, 2000 Aug 1, 97(16), 8754 - 61 Striking a balance: modulation of the actin cytoskeleton by Salmonella; Galan JE et al.; Salmonella spp . have evolved the ability to enter into cells that are normally nonphagocytic . The internalization process is the result of a remarkable interaction between the bacteria and the host cells . Immediately on contact, Salmonella delivers a number of bacterial effector proteins into the host cell cytosol through the function of a specialized organelle termed the type III secretion system . Initially, two of the delivered proteins, SopE and SopB, stimulate the small GTP-binding proteins Cdc42 and Rac . SopE is an exchange factor for these GTPases, and SopB is an inositol polyphosphate phosphatase . Stimulation of Cdc42 and Rac leads to marked actin cytoskeleton rearrangements, which are further enhanced by SipA, a Salmonella protein also delivered into the host cell by the type III secretion system . SipA lowers the critical concentration of G-actin, stabilizes F-actin at the site of bacterial entry, and increases the bundling activity of the host-cell protein T-plastin (fimbrin) . The cellular responses stimulated by Salmonella are short-lived; therefore, immediately after bacterial entry, the cell regains its normal architecture . Remarkably, this process is mediated by SptP, another target of the type III secretion system . SptP exert its function by serving as a GTPase-activating protein for Cdc42 and Rac, turning these G proteins off after their stimulation by the bacterial effectors SopE and SopB . The balanced interaction of Salmonella with host cells constitutes a remarkable example of the sophisticated nature of a pathogen/host relationship shaped by evolution through a longstanding coexistence. Aten Primaria, 2000 May 31, 25(9), 634 - 8 {Results of the application of a health test in a population of immigrants}; Lacalle Rodriguez-Labajo M et al.; OBJECTIVE: To describe the demographic characteristics and the results of a healthcare exam of immigrants . DESIGN: A retrospective descriptive study . SETTING: Rural doctor office of Villafranca del Castillo . Madrid . PATIENTS: All immigrants (n = 76) that came for care between May of 1996 and May of 1998 . INTERVENTIONS: History, physical exam and basic laboratory tests . RESULTS: Demographic data: 82% are women with a medium age of 33 years (SD 8.49) . Their places of origin are Central America: 70%, Philippines: 20%, Africa: 5% and South America: 3% . 97% of them work as household employees or gardeners . They have been living in Spain for an average time of 56 months . Health data: 21.1% are smokers and 17.1% low risk drinkers . 64.5% lack tetanus vaccine and 11.8% lack both tetanus and rubeola vaccines . Serologic test for HBV are negative in 68.4% . 14.5% have past infection and there are no cases of chronic or active infection . PPD is over 10 mm in 35.5%, and between 5 and 10 mm in 7.9% . Prevalence of active TBC is 0% . Stool culture is positive in 6.5% . Salmonella tiphy is identified in one case . Stool examination for ova and parasites is positive in 42.1% of the patients . Protozoos (88%) are more common than helminths (12%) . CONCLUSIONS: This study reveals a selective young and healthy immigrant group . The low presence of hepatitis B and tuberculosis infections are notable . The majority present parasites in stool samples. J Radiol, 2000 Aug, 81(8), 899 - 901 {Infected aneurysm of abdominal aorta: early CT finding}; Sellami D et al.; Infected abdominal aortic aneurysm is an uncommon but life-threatening disease, especially in case of salmonella infection . Early CT findings should be well known in order to allow immediate diagnosis and accurate management . The authors present an early CT finding of a salmonella infected aneurysm of abdominal aorta in an HIV-infected patient . This pattern consists in a slight-enhancing focal densification of periaortic soft-tissue, while aorta remains of normal size . Within two weeks, infection progressed to the constitution of an infected aneurysm . This CT finding seems to be initial to previously described signs. J Infect Dis, 2000 Aug, 182(2), 474 - 81 Epub 2000 Jul 18. Natural T, gammadelta, and NK cells in mycobacterial, Salmonella, and human immunodeficiency virus infections; Jason J et al.; NK cells, gammadelta T cell antigen receptor chain-positive cells, and CD3(+)CD16/56(+) (natural T {NT}) cells are involved in innate immunity and immunoregulation; however, their role in clinical infection is not well defined . Cytofluorometric analysis was used to examine peripheral blood from bacteremic, nonbacteremic, and healthy human immunodeficiency virus (HIV)-positive and -negative persons in Malawi, Africa . Mycobacteremia was associated with a higher proportion of CD3(+)CD8(-) gammadelta cells (median, 16.6% vs . 0.7% for all other cells; P<.001), and Salmonella bacteremia was associated with a higher proportion of NT cells (4.3% vs . 2.2%; P= . 002) . HIV plasma RNA levels were weakly positively correlated with NT cells (rs=.39; P=.002), NK cells (rs=.38; P=.003), and gammadelta cells (rs=.43; P<.001) . Compared with patients who survived, patients who died had a higher percentage of NT cells (3.7% vs . 1 . 9%; P=.017) and a higher percentage of NT cells that spontaneously produced interferon-gamma (2.4% vs . 1.2%; P=.035) . The data support the clinical relevance of gammadelta and NT cells in mycobacterial, Salmonella, and HIV infections and of NT cells in mortality. J Food Prot, 2000 Jul, 63(7), 958 - 60 Isolation of Salmonella spp . from the housefly, Musca domestica L., and the dump fly, Hydrotaea aenescens (Wiedemann) (Diptera: Muscidae), at caged-layer houses; Olsen AR et al.; Flies, especially houseflies, are widely recognized as potential reservoirs and vectors of foodborne Salmonella pathogens . In this study, flies were collected at caged-layer facilities that had produced eggs that were implicated as the food vehicle in two recent outbreaks of Salmonella Enteritidis infections . The flies were separated by species into pools for microbiological testing . A total of 15 species pools of houseflies, Musca domestica L., and 7 species pools of bronze dump flies, Hydrotaea aenescens (Wiedemann) (Diptera: Muscidae), were analyzed . Salmonella Enteritidis was isolated from 2 of the 15 pools of houseflies . Other species of Salmonella were isolated from three pools of flies, including Salmonella Infantis from houseflies and from dump flies and Salmonella Heidelberg from houseflies . Salmonella Mbandaka was isolated from a lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae). J Food Prot, 2000 Jul, 63(7), 876 - 83 Attachment and growth of Salmonella Chester on apple fruits and in vivo response of attached bacteria to sanitizer treatments; Liao CH et al.; Attachment and growth of Salmonella Chester on fresh-cut apple disks and in vivo response of attached bacteria to sanitizer treatments were investigated . Apple disks (14 mm in diameter and 3 to 4 mm in thickness) were immersed in a bacterial suspension that contained 8.17 log CFU/ml of Salmonella Chester and air dried at room temperature for 10 min . After two rinses, the population of Salmonella Chester retained on apple disks that contained no skin was 13 to 19% higher than that retained on disks that contained skin, indicating that Salmonella Chester attached more firmly to the surfaces of injured tissue than to the unbroken skin . The number of bacteria attached to the disk was not affected by the immersion time but was directly proportional to the concentration of bacteria in the suspension . The distribution of artificially inoculated Salmonella Chester on the surfaces of three different parts of whole fruit was determined; 94% of attached bacteria was found on the stem and calyx cavity areas and 6% on the skin of the remaining area of the fruit . Despite their acidic pH (4.1), apple disks supported the growth of Salmonella Chester at 20 degrees C but not at 8 degrees C . All four sanitizers tested in the study, including 6% hydrogen peroxide, 2% trisodium phosphate, 0.36% calcium hypochlorite, and 1.76% sodium hypochlorite, were effective in reducing the population of Salmonella Chester on apple disks by 1 to 2 logs . However, 5 to 13% of bacteria survived the sanitizer treatments . Hydrogen peroxide, which reduced the population of Salmonella Chester on skin by 3 to 4 logs and the population of bacteria on stem or calyx by 1 to 2 logs, was the most effective among the four sanitizers tested . Firm attachment of bacteria on calyx, stem, and injured tissue and partial resistance of attached bacteria to sanitizer treatments are two major obstacles to be considered when developing methods for cleaning and decontaminating apple fruits destined for juice production and fresh consumption. J Food Prot, 2000 Jul, 63(7), 871 - 5 Reduction of Salmonella spp . and strains of Escherichia coli O157:H7 by gamma radiation of inoculated sprouts; Rajkowski KT et al.; There have been several recent outbreaks of salmonellosis and infections with Escherichia coli O157:H7 linked to the consumption of raw sprouts . Use of ionizing radiation was investigated as a means to reduce or to totally inactivate these pathogens, if present, on the sprouts . The radiation D value, which is the amount of irradiation in kilograys for a 1-log reduction in cell numbers, for these pathogens was established using a minimum of five doses at 19 +/- 1 degrees C . Before inoculation, the sprouts were irradiated to 6 kGy to remove the background microflora . The sprouts were inoculated either with Salmonella spp . cocktails made with either meat or vegetable isolates or with E . coli O157:H7 cocktails made with either meat or vegetable isolates . The radiation D values for the Salmonella spp . cocktails on sprouts were 0.54 and 0.46 kGy, respectively, for the meat and vegetable isolates . The radiation D values for the E . coli O157:H7 cocktails on sprouts were 0.34 and 0.30 kGy, respectively, for the meat and vegetable isolates . Salmonella was not detected by enrichment culture on sprouts grown from alfalfa seeds naturally contaminated with Salmonella after the sprouts were irradiated to a dose of 0.5 kGy or greater . Ionizing radiation is a process that can be used to reduce the population of pathogens on sprouts. J Food Prot, 2000 Jul, 63(7), 867 - 70 Commercial field trial evaluation of mucosal starter culture to reduce Salmonella incidence in processed broiler carcasses; Bailey JS et al.; A series of four paired-house studies was conducted in Arkansas, Alabama, and Georgia (two farms) to determine the efficacy of Mucosal Starter Culture (MSC) in eliminating or reducing salmonellae in broiler chickens . Randomly designated chicks were treated twice with MSC . First they were sprayed with an MSC solution using a spray vaccination cabinet in the hatchery, and then they received MSC in the first drinking water at the growing house . Chicks were grown in identically constructed and equipped paired houses managed by the same grower . At the end of grow-out, broilers were tested for the presence of salmonellae on the farm and during processing . In three trials where no hatchery salmonellae were found, less salmonellae were found on MSC-treated chickens compared to untreated chickens . On the farm at the end of grow-out, salmonellae were detected in 54 of 150 untreated control chickens compared to 40 of 180 MSC-treated chickens . In the processing plant, significantly (P < or = 0.05) more salmonellae were detected on prechill untreated control carcasses (23 of 180) compared to MSC-treated carcasses (12 of 180) and on untreated postchill processed carcasses (9 of 180) compared to MSC-treated carcasses (0 of 180) . In one trial where appreciable (28% of egg shell samples) salmonellae was found before treatment with the MSC, more salmonellae were found in the treated birds than in the control birds both on the farm and after processing . These data confirm that when salmonellae levels were controlled in the hatchery, a significant reduction in the salmonellae was found on processed broiler carcasses treated with MSC and that this reduction in salmonellae was carried through processing to the final processed carcass, thus potentially reducing consumer exposure to salmonellae. J Bacteriol, 2000 Aug, 182(16), 4406 - 13 Tissue-specific gene expression identifies a gene in the lysogenic phage Gifsy-1 that affects Salmonella enterica serovar typhimurium survival in Peyer's patches; Stanley TL et al.; In vivo expression technology was used to identify Salmonella enterica serovar Typhimurium genes that are transcriptionally induced when the bacteria colonize the small intestines of mice . These genes were subsequently screened for those that are transcriptionally inactive during the systemic stages of disease . This procedure identified gipA, a gene that is specifically induced in the small intestine of the animal . The gipA gene is carried on the lambdoid phage Gifsy-1 . Consistent with the expression profile, the sole defect conferred by a gipA null mutation is in growth or survival in a Peyer's patch . The gipA strain is wild type in its ability to initially colonize the small intestine and invade the intestinal epithelium . The mutant also survives and propagates at wild-type levels during the systemic stages of disease . The gipA open reading frame is homologous to a family of putative insertion sequence elements, although our evidence shows that transposition is not required for gipA function in the Peyer's patch . These results suggest that the bacteria sense and respond to the particular environment of the Peyer's patch, a critical site for the replication of Salmonella serovar Typhimurium. J Bacteriol, 2000 Aug, 182(16), 4375 - 9 rpoS mutants in archival cultures of Salmonella enterica serovar typhimurium; Sutton A et al.; Long-term survival under limited growth conditions presents bacterial populations with unique environmental challenges . The existence of Salmonella enterica serovar Typhimurium cultures undisturbed in sealed nutrient agar stab vials for 34 to 45 years offered a unique opportunity to examine genetic variability under natural conditions . We have initiated a study of genetic changes in these archival cultures . We chose to start with examination of the rpoS gene since, among gram-negative bacteria, many genes needed for survival are regulated by RpoS, the stationary-phase sigma factor . In each of 27 vials examined, cells had the rpoS start codon UUG instead of the expected AUG of Salmonella and Escherichia coli strains recorded in GenBank . Ten of the 27 had additional mutations in the rpoS gene compared with the X77752 wild-type strain currently recorded in GenBank . The rpoS mutations in the 10 strains included two deletions as well as point mutations that altered amino acid sequences substantially . Since these stored strains were derived from ancestral cells inoculated decades ago and remained undisturbed, it is assumed that the 10 rpoS mutations occurred during storage . Since the remaining 17 sequences were wild type (other than in the start codon), it is obvious that rpoS remained relatively stable during decades of sealed storage. Toxicol Sci, 2000 Aug, 56(2), 351 - 6 Mutagenicity studies of benzidine and its analogs: structure-activity relationships; Chung KT et al.; The Ames SALMONELLA:/microsome assay was employed to test the mutagenicity of benzidine and its analogs using strains TA98 and TA100 in the presence and absence of Aroclor 1254-induced rat S9 mix . 3,3'-Dichlorobenzidine-2HCl and 4,4'-dinitro-2-biphenylamine were directly mutagenic to TA98, while 4,4'-dinitro-2-biphenylamine was directly mutagenic to both TA98 and TA100 in the absence of S9 mix . 2-Aminobiphenyl, 3-aminobiphenyl, and 3,3'-5,5'-tetramethylbenzidine were not mutagenic in either strains in the presence or absence of S9 . In the presence of S9 mix, 4-aminobiphenyl, benzidine, 3, 3'-dichlorobenzidine-2HCl, 3,3'-dimethoxybenzidine, 3,3'-4, 4'-tetraaminobiphenyl, o-tolidine, N, N-N', N'-tetramethylbenzidine, and 4,4'-dinitro-2-biphenylamine were mutagenic to TA98; 4-aminobiphenyl, 3,3'-dichlorobenzidine-2HCl, 3, 3'-dimethoxybenzidine, and 4,4'-dinitro-2-biphenylamine were mutagenic to TA100 . Physicochemical parameters of these compounds including oxidation potentials, the energy difference between the lowest unoccupied molecular orbital and the highest occupied molecular orbital, ionization potentials, dipole moment, relative partition coefficient, and basicity did not correlate with their bacterial mutagenic activities. Acta Paediatr Taiwan, 2000 Jan-Feb, 41(1), 43 - 6 Toxic megacolon in Salmonella colitis: report of two cases; Tiao MM et al.; Toxic megacolon is a complication that usually presents in inflammatory bowel disease such as ulcerative colitis or Crohn's disease . It also occurs in typhoid fever, acute bacillary dysentery, amebic colitis, ischemic colitis, pseudomembranous colitis and severe salmonellosis . This report describes the occurrence of toxic megacolon in two young children with Salmonella colitis manifesting as abdominal distension, diarrhea and fever . The clinical course of these two cases suggests that toxic megacolon is a severe complication of salmonellosis in children, irrespective of the use of antibiotics . In the light of its paucity in children and severity, accurate diagnosis and appropriate intensive medical-surgical management is essential. Acta Paediatr Taiwan, 2000 Jan-Feb, 41(1), 28 - 32 Typhoid fever in children: a fourteen-year experience; Chiu CH et al.; From 1982 to 1995, 71 children admitted in our medical center were diagnosed to have typhoid fever by culture or serology . Of the 71 children, most (83%) were aged 5-15 years . These children usually presented with fever and gastrointestinal symptoms, including abdominal pain, diarrhea, nausea or vomiting, and constipation . Hepatosplenomegaly was the most common physical sign observed and abdominal tenderness ranked the second . Thrombocytopenia occurring in 9 patients (13%) was the most common mode of complication . Other complications included intestinal perforation (3%), rectal bleeding (3%), ascites or pleural effusion (4%), and meningitis (1%) . The incidence of complications tended to be higher among children 5 years of age or older (p = 0.31) . Most patients responded well to appropriate antimicrobial therapies . There was no mortality . Relapse was observed in two children, although both had received 10 days of chloramphenicol therapy . The clinical isolates of Salmonella typhi were susceptible in vitro to all the antibiotics tested, including chloramphenicol, which, however, showed a higher MIC90 level than other drugs tested . In conclusion, there were age-specific differences of typhoid fever in children in terms of the incidence and morbidity and antibiotic resistance of S . typhi has not been a problem in this area at least up to 1995. Acta Paediatr Taiwan, 1999 Sep-Oct, 40(5), 339 - 40 Typhoid fever presenting as infection-associated hemophagocytic syndrome: report of one case; Chien YH et al.; This report describes a 13-year-old boy who had high fever with severe pancytopenia and acute psychosis as initial presentation . Bone marrow examination was compatible with infection-associated hemophagocytic syndrome (IAHS) . Blood culture showed no growth of bacteria while the culture of bone marrow yielded Salmonella typhi . The clinical condition stabilized shortly after the use of ceftriaxone . This case illustrates that typhoid fever must be included in the differential diagnosis of IAHS . In cases with IAHS, bacterial culture as well as morphological study of bone marrow is necessary for the evaluation of etiological agent and to avoid injudicious use of chemotherapy. Am J Epidemiol, 2000 Jul 15, 152(2), 171 - 7 How many foodborne outbreaks of Salmonella infection occurred in France in 1995? Application of the capture-recapture method to three surveillance systems; Gallay A et al.; Despite control measures, foodborne outbreaks of non-typhi Salmonella infection continue to occur in developed countries . The authors aimed to assess the number of foodborne Salmonella outbreaks that occurred in France in 1995 using a capture-recapture approach . Data from three sources--the National Public Health Network (NPHN), the Ministry of Agriculture (MA), which receives mandatory notification, and the National Salmonella and Shigella Reference Center (NRC)-were collected . Matching algorithms permitted identification of matched outbreaks . The total number of outbreaks was estimated by log-linear modeling taking into account source dependencies and the variable catchability . The final estimate was adjusted for the positive predictive value (66%) of the NRC case definition . The dependence between the NPHN and the MA was also evaluated by means of a qualitative survey . A total of 716 foodborne Salmonella outbreaks were reported to the three sources, and 108 matches were identified . The best-fitting model, taking into account a positive dependence between the NPHN and MA sources, gave an estimate of 757 outbreaks . The sensitivity was 15% for the NPHN, 10% for the MA, and 50% for the NRC . In France, routine mandatory reporting of foodborne Salmonella outbreaks is very incomplete, and it is not representative of the serotype and the type of outbreak. J Vet Med Sci, 2000 Jun, 62(6), 615 - 9 Detection of Salmonella by using the colorimetric DNA/rRNA sandwich hybridization in microtiter wells; Namimatsu T et al.; A rapid and readily available DNA probe kit was developed for the detection of Salmonella spp . This kit utilized the colorimetric DNA/rRNA sandwich hybridization method in microtiter wells . Within 3 hr Salmonella spp . in selective enrichment broth cultures were detected by the DNA probe kit . The kit effectively identified all of 187 strains of Salmonella tested and yielded no false-positive reactions in the examination of 674 pure cultures of non-salmonellae . The DNA probe kit could detect 10(5) cfu/ml in pure culture . A total of 379 naturally contaminated samples (raw chicken meat, liquid egg, animal feeds, poultry feces and frozen foods) were tested, both by the standard culture method and the DNA probe kit . The 169 of these samples were culture positive and 210 were culture negative . The sensitivity of the DNA probe kit was 98.2% (166/169) and the specificity was 99.5% (209/210) . These results show that the DNA probe kit is a useful tool to examine a large number of various samples for contamination by Salmonella spp . in food and livestock industry. J Vet Med Sci, 2000 Jun, 62(6), 565 - 70 Chronological recognition by chicken of antigenic polypeptides in Salmonella enteritidis with different plasmid profiles: relationship to infection rate; Barbour EK et al.; The antigenic polypeptides in Salmonella Enteritidis (SE) were chronologically recognized by the chicken immune system, using Western immunoblotting . Broiler chicks challenged at three days of age with SE strain carrying the most prevalent plasmid profile of 14.1 and about (approximately) 50 kb were bled at 17, 24, 31, 38 and 45 days of age . Pooled sera of blood collected at each age was reacted by Western immunoblotting with banded polypeptides of three predominant SE strains that acquired the following respective plasmid profiles: 14.1 kb; 14.1 and approximately 50.0 kb; and 1.8, 14.1 and approximately 50.0 kb . The immunoblots of each pooled sera collected at a specific age against the three SE strains were similar . More specifically, the early immune response at 17 days of age had antibodies recognizing only one polypeptide in the three SE strains namely, the 35.8 kDa . At 24 or 31 days of age, the acquired immunity to infection had antibodies recognizing five similar polypeptides in the three SE strains namely, the 14.4 (fimbriae protein), 21.5 (fimbriae protein), 30.5, 35.8, and 66.2 kDa . At 38 and 45 days of age, the antibodies recognized additional polypeptides namely, the 41.5 and 55.6 kDa, respectively . The recognition of the 41.5 and 55.6 kDa polypeptides at 45 days of age was associated with higher invasiveness of SE to spleens and livers (15.6%) and in higher cecal colonization (59.4%) in comparison to absence of recognition to the two polypeptides at 31 days of age associated with low infectivity to spleens (0%), livers (3.1%), and ceca (9.4%). Przegl Lek, 2000, 57(1), 54 - 5 {Hemolytic-uremic syndrome in a patient with bacterial food poisoning}; Kalinowska-Nowak A et al.; A rare case of a 47-year-old man with bacterial food poisoning due to Salmonella enteritidis, complicated by haemolitic-uraemic syndrome was described. Microb Pathog, 2000 Aug, 29(2), 121 - 6 Experimental Salmonella typhi infection in the domestic pig, Sus scrofa domestica; Metcalf ES et al.; The domestic pig, Sus scrofa domestica, was examined as a model for typhoid fever, a severe and systemic disease of humans caused by Salmonella typhi . Six pigs were inoculated 1 week post-weaning with approximately 10(10)colony forming units (cfu) of wild type Salmonella typhi strain ISP1820 intranasally and observed for 3 weeks . S . typhi was cultured from the tonsils of 50% of the pigs at necropsy . Cultures from all other organs analysed (ileum, colon, spleen and liver) were negative . No clinical or histopathological signs of disease were observed . Pigs inoculated in parallel with swine-virulent S . choleraesuis all exhibited signs of systemic salmonellosis indicating that the parameters of the experimental infection with S . typhi (e.g . route) were appropriate . Whereas the pig has a gastrointestinal tract that is very similar to humans, our results indicated that the unique features of host and microbe interaction needed to produce typhoid fever were not mimicked in swine . Nevertheless, our observation of tonsillar involvement was consistent with former observations of S . choleraesuis and S . typhimurium infections in swine and supports a role for the tonsil in all porcine salmonella infections . J Comp Pathol, 2000 Jul, 123(1), 1 - 6 Effect of experimental zinc deficiency on immunological responses in Salmonella-infected guinea-pigs; Gupta RP et al.; Cellular and humoral immune responses to Salmonella dublin infection were studied in guinea-pigs given zinc-deficient (ZnD) or zinc-adequate (ZnA) diet, containing 1.03 or 52.4 mg Zn/kg, respectively . On day 30, each animal of each dietary group was inoculated intraperitoneally with 10(6)viable cells of S . dublin strain 493 . On the 15th day after infection, the immune responses were assessed by skin hypersensitivity (SH) tests and enzyme-linked immunosorbent assay (ELISA) for serum antibody with Salmonella -extract antigen . ZnD animals had significantly decreased ability to produce Salmonella -specific immediate and delayed type SH responses . These results were further substantiated by histological examination of skin sections . The ELISA indicated significantly lower Salmonella -specific serum antibody titres in ZnD animals than in ZnA animals . Mean viable counts of S . dublin in the liver and spleen of ZnD animals were significantly higher than those in ZnA animals . Emerg Infect Dis, 2000 Jul-Aug, 6(4), 420 - 1 Drug-resistant Salmonella enterica serotype paratyphi A in India; Chandel DS et al.; The incidence of enteric fever caused by Salmonella enterica serotype Paratyphi A has been increasing in India since 1996 . In 1998, the incidence of enteric fever caused by drug- resistant S . Paratyphi A abruptly increased in the New Delhi region . In the first 6 months of 1999, 32% of isolates were resistant to both chloramphenicol and cotrimoxazole and another 13% were resistant to more than two antibiotics. Emerg Infect Dis, 2000 Jul-Aug, 6(4), 401 - 3 Antimicrobial resistance in Salmonella enteritidis, southern Italy, 1990-1998; Nastasi A et al.; During 1990 to 1998, we identified multidrug-resistant isolates of Salmonella Enteritidis in southern Italy . Plasmids containing class I integrons and codifying for synthesis of extended- spectrum beta-lactamases were detected . Active surveillance for resistance to antimicrobial agents is needed to guard against the possible spread of resistant clones. Anal Chem, 2000 Jul 1, 72(13), 2809 - 13 A Salmonella detection system using an engineered DNA binding protein that specifically captured a DNA sequence; Takeuchi A et al.; We have developed a novel method for the detection with high selectivity of a double-stranded DNA fragment using an engineered DNA-binding protein, DnaA IV, a fusion protein of the DNA-binding domain of DnaA and glutathione S-transferase . The DNA fragment detection system is based on DNA-protein interaction and consists of sequence-specific binding of DnaA IV with a DNA fragment containing the DnaA box . DnaA IV, while not capturing other DNA fragments, specifically captured that containing the DnaA box . Because the oriC fragment containing the DnaA box could be specifically amplified by PCR from the genus Salmonella, the DNA fragment detection system was adapted for the detection of Salmonella . The Salmonella detection system using PCR amplification and the engineered DNA-binding protein could distinguish 104 cfu/mL Salmonella from 106 cfu/ mL contaminating bacteria. Enferm Infecc Microbiol Clin, 2000 Mar, 18(3), 125 - 32 {Epidemiology of non-typhoid salmonellosis in a hospital in Pontevedra (1994-1997)}; Bellver P et al.; BACKGROUND: Since data on non-typhoidal salmonellosis in our health care area are scarce, we undertook an epidemiological study covering a four year period (1994-1997) . METHODS: Retrospective descriptive study carried out through review of the medical and clinical microbiologic records at Hospital Provincial de Pontevedra . Culture, isolation, identification, antibiotic susceptibility and serotypification were done according to usual Clinical Microbiology protocols . RESULTS: Along the period under study 459 cases of non-typhoidal salmonellosis were diagnosed . The relative incidence was higher among pediatric than adult patients . Between 1994-1996 top incidence was detected in August, while in 1997 another maximum was found in April, closely related to climatic variations . The most frequent serogroup was D, with an increase in serogroup B since 1996 . We found 16 different serotypes, being the more frequent in decreasing order Enteritidis (87.2%), Typhimurium (3.6%) and Hadar (2.3%) . This distribution shows differences with regard to other national series covering a similar period of time . The more frequently detected antibiotic resistance was to ampicillin (39.0% strains), ampicillin-sulbactam (17.6%) and nalidixic acid (5.9%) . Neither 3rd-generation cephalosporines nor fluoroquinolones resistance was detected . Serotype Typhimurium was the most resistant . We found association between certain resistance patterns and serotypes Hadar, Paratyphi B and Typhimurium . Most diagnosed cases corresponded to acute gastroenteritis (95.6%) . Patients under 3 and over 69 suffered more frequently from extraintestinal salmonellosis . CONCLUSIONS: The high incidence of alimentary toxinfection due to Salmonella spp . in our area should warrant strict epidemiological surveillance programmes to detect sources of infection, evaluate sanitary control measures and use of antibiotics. J Med Assoc Thai, 1997 Oct, 80(10), 613 - 8 Nontyphoidal Salmonella diarrhea in Thai children: a study at Bamrasnaradura Hospital, Nonthaburi, Thailand; Moolasart P et al.; From July 1, 1994 to June 30, 1996, 394 children with Nontyphoidal Salmonella diarrhea were studied at Bamrasnaradura Infectious Disease Hospital in Thailand . The ages ranged from 1 month to 12 years (mean, 1.4 years) . Eighty-seven per cent of patients were in the first 2 years of life . Diarrhea, mostly acute with watery stool and fever were the most common presenting symptoms . The duration of diarrhea ranged from 1 to 20 days (mean, 5.2 days) . Salmonella group B was the most common serogroup (56.1%) . Most isolates were multiresistant strains, however, they were all sensitive to norfloxacin . Four (1%) patients were HIV-infected . Pneumonia found in 2 patients (0.5%) and septicemia in 1 patient (0.3%) . None of the patients died . We conclude that nontyphoidal Salmonella diarrhea in children is still endemic in Thailand, especially among infants and high multidrug resistance occurs. Arthritis Rheum, 2000 Jul, 43(7), 1527 - 34 Modification of disease outcome in Salmonella-infected patients by HLA-B27; Ekman P et al.; OBJECTIVE: To study whether HLA-B27 modifies the outcome of Salmonella infection in vivo . METHODS: The frequency of HLA-B27 was determined in 198 Salmonella-infected patients and 100 healthy controls by immunofluorescence and polymerase chain reaction . The excretion of Salmonella was monitored at monthly intervals . The symptoms of acute infection and possible joint involvement were evaluated using questionnaires . RESULTS: Thirty-eight of 198 Salmonella-infected patients (19.2%) and 13 of 100 healthy controls (13.0%) were HLA-B27 positive . The excretion of Salmonella did not differ significantly between HLA-B27-positive and -negative patients, or for patients with versus those without joint symptoms . As many as 35 patients (17.7%) reported Salmonella-triggered joint symptoms . Three of 14 patients (21.4%) with arthralgia, 5 of 13 patients (38.5%) with probable reactive arthritis (ReA), and 6 of 8 patients (75%) with confirmed ReA were HLA-B27 positive . The duration and severity of joint symptoms directly correlated with HLA-B27 positivity . Women reported Salmonella-induced pain and swelling of joints more frequently than men (P = 0.07 and P = 0.03, respectively) . Patients with Salmonella-triggered joint symptoms reported abdominal pain and headache more frequently than patients without joint symptoms (P = 0.05 and P = 0.004, respectively) . CONCLUSION: HLA-B27 did not (at least, not strongly) confer susceptibility to Salmonella infection . Salmonella excretion correlated neither with HLA-B27 positivity nor with the occurrence of joint symptoms . Joint symptoms were surprisingly common during or after Salmonella infection . HLA-B27-positive patients had a significantly increased risk of developing joint and tendon symptoms . Moreover, HLA-B27 positivity correlated with the development of more severe and prolonged joint symptoms. Commun Dis Public Health, 2000 Jun, 3(2), 95 - 100 Four linked outbreaks of Salmonella enteritidis phage type 4 infection--the continuing egg threat; Ejidokun OO et al.; Four outbreaks of Salmonella enteritidis phage type (PT) 4 occurred among guests at functions for which a single commercial caterer supplied food . Retrospective cohort studies were used to describe the epidemiology of three of these outbreaks and identify the vehicle(s) responsible . Of 172 guests at these three events, 47 fitted the clinical case definition for illness and 24 cases were confirmed to have S . enteritidis PT4 infection . Food containing raw egg was identified epidemiologically as the likely vehicle of infection in two of the three outbreaks (odds ratios (OR) and 95% confidence intervals 9.1 (2.2-39.9) and 6.9 (1.2-46.4)) . Logistic regression analysis yielded OR = 10.7 (p = 0.0022) and OR = 9.3 (p = 0.015) for egg consumption in two of the outbreaks . These outbreaks highlighted the continuing need to remind the public and commercial caterers of the potential high risks of contracting salmonella from shell eggs . Education of caterers includes advice to obtain eggs and other products from reputable and identifiable suppliers. Commun Dis Public Health, 2000 Jun, 3(2), 90 - 4 Survey of raw egg use by home caterers; Sin J et al.; Outbreaks of egg related salmonella infection continue to occur despite over ten years of national guidance on this subject . Fifty-four out of 70 registered home caterers in Cheshire responded to a telephone questionnaire, which revealed that a sixth prepared raw egg dishes containing shell eggs, none used pasteurised egg, and advice about storage of eggs and handwashing was not always followed . A postal questionnaire sent to 13 wholesalers and major supermarket chains showed that pasteurised egg was available in large packs from wholesalers but not from supermarkets . It is time to consider new approaches to reinforce advice about pasteurised egg use for raw egg dishes, storage, and measures to prevent cross contamination . These findings have implications for the training of home caterers and the general public. Vet Rec, 2000 Jun 17, 146(25), 721 - 8 Pulmonary pathology of harbour porpoises (Phocoena phocoena) stranded in England and Wales between 1990 and 1996; Jepson PD et al.; The pathological changes observed in the lungs of 197 freshly dead to moderately decomposed harbour porpoises (Phocoenaphocoena) stranded in England and Wales between October 1990 and December 1996 were reviewed . In 135 (69 per cent of the cases) macroscopic nematode infections of the bronchial tract with Pseudalius inflexus and Torynurus convolutus, either singly or in combination, were recorded, and 106 (54 per cent) also had P inflexus within the pulmonary blood vessels . All the macroscopically parasitised porpoises were adults or juveniles although two neonates had histological evidence of nematode infection . There were 62 cases of mild to severe, subacute to chronic bronchitis and bronchiolitis, 113 cases of mild to severe chronic granulomatous interstitial pneumonia, and 34 cases of mild to severe vasculitis or thrombovasculitis of pulmonary blood vessels attributable to these nematode infections . In 35 cases necropurulent or purulent (broncho)pneumonias were attributed either to secondary bacterial infections of the lungs or to septicaemias associated in seven cases with Streptococcus canis, in two cases with group B Salmonella species, in one case with Escherichia coli and in one case with Streptococcus lactis . The pulmonary lesions in 67 animals known or diagnosed to have been entrapped in fishing gear were non-specific and included persistent foam in the airways in 45 cases, diffuse congestion in 53, oedema in 50, and multifocal intra-alveolar haemorrhage in 33 cases . Seven cases of acute fibrinous or chronic fibrous pleuritis, seven cases of chronic necropurulent pneumonia associated with mycotic infections, four porpoises with traumatic lesions of the thorax and other parts of the body consistent with fatal attack from bottlenose dolphins (Tursiops truncatus), and one case of diffuse bronchointerstitial pneumonia associated with generalised morbillivirus infection were also recorded. Infect Immun, 2000 Aug, 68(8), 4782 - 5 Salmonella enterica serovars gallinarum and pullorum expressing Salmonella enterica serovar typhimurium type 1 fimbriae exhibit increased invasiveness for mammalian cells; Wilson RL et al.; Salmonella enterica serovars Gallinarum and Pullorum are S . enterica biotypes that exhibit host specificity for poultry and aquatic birds and are not normally capable of causing disease in mammalian hosts . During their evolution toward host restriction serovars Gallinarum and Pullorum lost their ability to mediate mannose-sensitive hemagglutination (MSHA), a phenotype correlated with adherence to certain cell types . Because adherence is an essential requirement for invasion of cells by bacterial pathogens, we examined whether MHSA type 1 fimbriae would increase the ability of serovars Pullorum and Gallinarum to invade normally restrictive cells . Serovars Gallinarum and Pullorum expressing S . enterica serovar Typhimurium strain LT2 type 1 fimbriae exhibited a 10- to 20-fold increased ability to adhere to and a 20- to 60-fold increased invasion efficiency of the human epithelial HEp-2 cell line . Invasion was accompanied by extensive ruffling of the membranes of the HEp-2 cells . In a murine ligated ileal loop model, a 32% increase in the number of M-cell ruffles was seen when serovar Gallinarum expressed serovar Typhimurium type 1 fimbriae. Infect Immun, 2000 Aug, 68(8), 4647 - 52 Constitutive expression of the Vi polysaccharide capsular antigen in attenuated Salmonella enterica serovar typhi oral vaccine strain CVD 909; Wang JY et al.; Live oral Ty21a and parenteral Vi polysaccharide vaccines provide significant protection against typhoid fever, albeit by distinct immune mechanisms . Vi stimulates serum immunoglobulin G Vi antibodies, whereas Ty21a, which does not express Vi, elicits humoral and cell-mediated immune responses other than Vi antibodies . Protection may be enhanced if serum Vi antibody as well as cell-mediated and humoral responses can be stimulated . Disappointingly, several new attenuated Salmonella enterica serovar Typhi oral vaccines (e.g., CVD 908-htrA and Ty800) that elicit serum O and H antibody and cell-mediated responses following a single dose do not stimulate serum Vi antibody . Vi expression is regulated in response to environmental signals such as osmolarity by controlling the transcription of tviA in the viaB locus . To investigate if Vi antibodies can be stimulated if Vi expression is rendered constitutive, we replaced P(tviA) in serovar Typhi vaccine CVD 908-htrA with the constitutive promoter P(tac), resulting in CVD 909 . CVD 909 expresses Vi even under high-osmolarity conditions and is less invasive for Henle 407 cells . In mice immunized with a single intranasal dose, CVD 909 was more immunogenic than CVD 908-htrA in eliciting serum Vi antibodies (geometric mean titer of 160 versus 49, P = 0.0007), whereas O antibody responses were virtually identical (geometric mean titer of 87 versus 80) . In mice challenged intraperitoneally with wild-type serovar Typhi 4 weeks after a single intranasal immunization, the mortality of those immunized with CVD 909 (3 of 8) was significantly lower than that of control mice (10 of 10, P = 0.043) or mice given CVD 908-htrA (9 of 10, P = 0.0065). Infect Immun, 2000 Aug, 68(8), 4485 - 91 Salmonella enterica serovar typhimurium waaP mutants show increased susceptibility to polymyxin and loss of virulence In vivo; Yethon JA et al.; In Escherichia coli, the waaP (rfaP) gene product was recently shown to be responsible for phosphorylation of the first heptose residue of the lipopolysaccharide (LPS) inner core region . WaaP was also shown to be necessary for the formation of a stable outer membrane . These earlier studies were performed with an avirulent rough strain of E . coli (to facilitate the structural chemistry required to properly define waaP function); therefore, we undertook the creation of a waaP mutant of Salmonella enterica serovar Typhimurium to assess the contribution of WaaP and LPS core phosphorylation to the biology of an intracellular pathogen . The S . enterica waaP mutant described here is the first to be both genetically and structurally characterized, and its creation refutes an earlier claim that waaP mutations in S . enterica must be leaky to maintain viability . The mutant was shown to exhibit characteristics of the deep-rough phenotype, despite its ability to produce a full-length core capped with O antigen . Further, phosphoryl modifications in the LPS core region were shown to be required for resistance to polycationic antimicrobials . The waaP mutant was significantly more sensitive to polymyxin in both wild-type and polymyxin-resistant backgrounds, despite the decreased negative charge of the mutant LPSs . In addition, the waaP mutation was shown to cause a complete loss of virulence in mouse infection models . Taken together, these data indicate that WaaP is a potential target for the development of novel therapeutic agents. Antimicrob Agents Chemother, 2000 Aug, 44(8), 2166 - 9 Antimicrobial resistance and spread of class 1 integrons among Salmonella serotypes; Guerra B et al.; The resistance profiles, for 15 antimicrobial agents, of 333 Salmonella strains representing the most frequent nontyphoidal serotypes, isolated between 1989 and 1998 in a Spanish region, and 9 reference strains were analyzed . All strains were susceptible to amikacin, ceftazidime, ciprofloxacin, and imipenem, and 31% were susceptible to all antimicrobials tested . The most frequent types of resistance were to sulfadiazine, tetracycline, streptomycin, spectinomycin, ampicillin, and chloramphenicol (ranging from 46 to 22%); 13% were resistant to these six drugs . This multidrug resistance pattern was found alone or together with other resistance types within serotypes Typhimurium (45%), Panama (23%), and Virchow (4%) . Each isolate was also screened for the presence of class 1 integrons and selected resistance genes therein; seven variable regions which carried one (aadA1a, aadA2, or pse-1) or two (dfrA14-aadA1a, dfrA1-aadA1a, oxa1-aadA1a, or sat1-aadA1a) resistance genes were found in integrons. Int J Food Microbiol, 2000 Jun 30, 58(1-2), 107 - 11 Analysis of Salmonella serotypes from selected carcasses and raw ground products sampled prior to implementation of the Pathogen Reduction; Hazard Analysis and Critical Control Point Final Rule in the US; Schlosser W et al.; In July 1996, the US Department of Agriculture (USDA), Food Safety and Inspection Service (FSIS), published the Pathogen Reduction; Hazard Analysis and Critical Control Point (HACCP) Systems final rule to improve food safety of meat and poultry products . The final rule established, among other requirements, pathogen reduction performance standards for Salmonella for food animal carcasses and raw ground products . The final rule is to be fully implemented in three stages in successively smaller federally inspected meat and poultry slaughter and processing establishments . Implementation began in January 1998 and was completed in January 2000 . Samples of carcasses of four species of food animals (cattle, swine, chickens, turkeys), and raw ground product from each of these species, were collected by FSIS from establishments prior to implementation of the final rule and cultured for Salmonella . This paper reports Salmonella serotype results of samples collected from June 1997 through August 1998 . These results represent a baseline for future comparisons. Trans R Soc Trop Med Hyg, 2000 Mar-Apr, 94(2), 212 - 5 Antibiotic susceptibility and genotypes of non-typhi Salmonella isolates from children in Kilifi on the Kenya coast; Oundo JO et al.; A 4-year retrospective study was undertaken at the Kilifi District Hospital on the coast of Kenya to determine the antibiotic-susceptibility patterns and genotypes of non-typhi Salmonella (NTS) isolates from children . Overall, during the period 1994-97, positive cultures were obtained from 543 (14%) of 3885 blood samples, 364 (30%) of 1210 stool samples and 143 (11%) of 1283 cerebrospinal fluid (CSF) samples . NTS were isolated from 151 (27.8%), 72 (19.8%), and 11 (7.7%) of these positive cultures, respectively . The total 234 NTS isolates were serotyped: the most frequent were Salmonella enterica serotype Enteritidis (41%) and S . enterica serotype Typhimurium (38%) . Antibiotic sensitivity testing was done using ampicillin (amp), chloramphenicol (chl), gentamicin (cn), co-trimoxazole (s-t), cefuroxime (cxm), ciprofloxacin (cip), cefotaxime (ctx), amoxicillin-clavulanic acid 20 micrograms-10 micrograms (amc), and tobramycin (tob) . Of the 234 isolates, 43 were sensitive to all antibiotics tested and 133 were multiple drug resistant (MDR) . The most common resistance type seen was amp, cn, cxm, s-t, ctx, amc, tob (36/234) . Our results indicate a high proportion of MDR amongst the isolates from Kilifi . We conclude that 2 major serotypes of salmonella, i.e., S . enterica serotype Typhimurium and S . enterica serotype Enteritidis, of micro-epidemic nature that have been previously unrecognized in Kilifi are responsible for infection in Kilifi district on the coast of Kenya and that over half (56.8%) of total NTS isolates are MDR. Rev Esp Quimioter, 1999 Dec, 12(4), 366 - 8 {Evolution of resistance to quinolones in Salmonella enterica in our setting}; Ruiz M et al.; Salmonella enterica is mainly associated with acute gastroenteritis; however, it is also associated with other more severe disease processes, for which quinolones are the treatment of choice . We retrospectively studied the evolution of resistance to nalidixic acid and ciprofloxacin of all the clinical isolates of S . enterica from 1992 to 1998 in our hospital environment . A total of 848 strains from feces, blood and other locations were studied . We detected an increase in the resistance to nalidixic acid from 12% in 1992 to 21.3% in 1998, especially in the Enteritidis and Hadar serotypes . We did not detect resistance to ciprofloxacin, but there was in increase in the MIC in the nalidixic acid-resistant strains . Although this is interpreted as sensitive according the the NCCLS criteria, if we apply the cutoff points established by MENSURA, 89.46% of the strains do not fit into this category (S <0.12 mg/l) . This puts into question the utility of quinolones in the long-term treatment of severe disease processes produced by this type of strain. J Bacteriol, 2000 Aug, 182(15), 4304 - 9 Reduction of Cob(III)alamin to Cob(II)alamin in Salmonella enterica serovar typhimurium LT2; Fonseca MV et al.; Reduction of the cobalt ion of cobalamin from the Co(III) to the Co(I) oxidation state is essential for the synthesis of adenosylcobalamin, the coenzymic form of this cofactor . A cob(II)alamin reductase activity in Salmonella enterica serovar Typhimurium LT2 was isolated to homogeneity . N-terminal analysis of the homogeneous protein identified NAD(P)H:flavin oxidoreductase (Fre) (EC 1.6.8.1) as the enzyme responsible for this activity . The fre gene was cloned, and the overexpressed protein, with a histidine tag at its N terminus, was purified to homogeneity by nickel affinity chromatography . His-tagged Fre reduced flavins (flavin mononucleotide {FMN} and flavin adenine dinucleotide {FAD}) and cob(III)alamin to cob(II)alamin very efficiently . Photochemically reduced FMN substituted for Fre in the reduction of cob(III)alamin to cob(II)alamin, indicating that the observed cobalamin reduction activity was not Fre dependent but FMNH(2) dependent . Enzyme-independent reduction of cob(III)alamin to cob(II)alamin by FMNH(2) occurred at a rate too fast to be measured . The thermodynamically unfavorable reduction of cob(II)alamin to cob(I)alamin was detectable by alkylation of the cob(I)alamin nucleophile with iodoacetate . Detection of the product, caboxymethylcob(III)alamin, depended on the presence of FMNH(2) in the reaction mixture . FMNH(2) failed to substitute for potassium borohydride in in vitro assays for corrinoid adenosylation catalyzed by the ATP:co(I)rrinoid adenosyltransferase (CobA) enzyme, even under conditions where Fre and NADH were present in the reaction mixture to ensure that FMN was always reduced . These results were interpreted to mean that Fre was not responsible for the generation of cob(I)alamin in vivo . Consistent with this idea, a fre mutant displayed wild-type cobalamin biosynthetic phenotypes . It is proposed that S . enterica serovar Typhimurium LT2 may not have a cob(III)alamin reductase enzyme and that, in vivo, nonadenosylated cobalamin and other corrinoids are maintained as co(II)rrinoids by reduced flavin nucleotides generated by Fre and other flavin oxidoreductases. J Bacteriol, 2000 Aug, 182(15), 4227 - 33 Identification of an alternative nucleoside triphosphate: 5'-deoxyadenosylcobinamide phosphate nucleotidyltransferase in Methanobacterium thermoautotrophicum delta H; Thomas MG et al.; Computer analysis of the archaeal genome databases failed to identify orthologues of all of the bacterial cobamide biosynthetic enzymes . Of particular interest was the lack of an orthologue of the bifunctional nucleoside triphosphate (NTP):5'-deoxyadenosylcobinamide kinase/GTP:adenosylcobinamide-phosphate guanylyltransferase enzyme (CobU in Salmonella enterica) . This paper reports the identification of an archaeal gene encoding a new nucleotidyltransferase, which is proposed to be the nonorthologous replacement of the S . enterica cobU gene . The gene encoding this nucleotidyltransferase was identified using comparative genome analysis of the sequenced archaeal genomes . Orthologues of the gene encoding this activity are limited at present to members of the domain Archaea . The corresponding ORF open reading frame from Methanobacterium thermoautotrophicum Delta H (MTH1152; referred to as cobY) was amplified and cloned, and the CobY protein was expressed and purified from Escherichia coli as a hexahistidine-tagged fusion protein . This enzyme had GTP:adenosylcobinamide-phosphate guanylyltransferase activity but did not have the NTP:AdoCbi kinase activity associated with the CobU enzyme of S . enterica . NTP:adenosylcobinamide kinase activity was not detected in M . thermoautotrophicum Delta H cell extract, suggesting that this organism may not have this activity . The cobY gene complemented a cobU mutant of S . enterica grown under anaerobic conditions where growth of the cell depended on de novo adenosylcobalamin biosynthesis . cobY, however, failed to restore adenosylcobalamin biosynthesis in cobU mutants grown under aerobic conditions where de novo synthesis of this coenzyme was blocked, and growth of the cell depended on the assimilation of exogenous cobinamide . These data strongly support the proposal that the relevant cobinamide intermediates during de novo adenosylcobalamin biosynthesis are adenosylcobinamide-phosphate and adenosylcobinamide-GDP, not adenosylcobinamide . Therefore, NTP:adenosylcobinamide kinase activity is not required for de novo cobamide biosynthesis. J Bacteriol, 2000 Aug, 182(15), 4207 - 15 Role of FliJ in flagellar protein export in Salmonella; Minamino T et al.; We isolated and characterized spontaneous mutants with defects in the 147-amino-acid Salmonella protein FliJ, which is a cytoplasmic component of the type III flagellar export apparatus . These mutants, including ones with null mutations, have the ability to form swarms on motility agar plates after prolonged incubation at 30 degrees C; i.e., they display a leaky motile phenotype . One mutant, SJW277, which formed significantly bigger swarms than the others, encoded only the N-terminal 73 amino acids of FliJ, one-half of the protein . At 30 degrees C, overproduction of this mutant protein improved, to wild-type levels, both motility and the ability to export both rod/hook-type (FlgD; hook capping protein) and filament-type (FliC; flagellin) substrates . At 42 degrees C, however, export was inhibited, indicating that the mutant FliJ protein was temperature sensitive . Taking advantage of this, we performed temperature upshift experiments, which demonstrated that FliJ is directly required for the export of FliC . Co-overproduction of FliJ and either of two export substrates, FliE or FlgG, hindered their aggregation in the cytoplasm . We conclude that FliJ is a general component of the flagellar export apparatus and has a chaperone-like activity for both rod/hook-type and filament-type substrates. Am J Gastroenterol, 2000 Jun, 95(6), 1495 - 502 Phagocytosis, killing, lymphocyte-mediated antibacterial activity, serum autoantibodies, and plasma endotoxins in inflammatory bowel disease; Caradonna L et al.; OBJECTIVE: Alteration of mucosal and systemic immune responses may play an important role in the pathogenesis of inflammatory bowel disease (IBD) . The aim of this study was to evaluate natural immune responses (i.e., phagocytosis, killing, and antibacterial activity), serum autoantibodies (antineutrophil cytoplasmic antibodies {ANCA} and anti-lactoferrin {LF} antibodies), and plasma endotoxins in patients affected by ulcerative colitis (UC) and Crohn's disease (CD) . METHODS: Blood samples were obtained from 71 patients with UC, 32 patients with CD, and 32 control subjects . Disease activity was scored using Truelove's criteria in patients with UC and the Crohn's Disease Activity Index (CDAI) in patients with CD . Candida albicans served as a target for evaluation of phagocytosis and killing exerted by polymorphonuclear cells (PMN) and monocytes (MO), whereas Salmonella typhi was used for assessing lymphocyte-mediated antibacterial activity . ANCA were detected by indirect immunofluorescence, whereas anti-LF antibodies were assayed by means of enzyme-linked immunosorbent assay . Plasma endotoxins were measured by Limulus amoebocyte lysate assay . RESULTS: Phagocytosis and killing exerted by PMN and MO, as well as lymphocyte-mediated antibacterial activity, were significantly reduced (p < 0.0001) in patients affected by UC and CD in comparison with controls, irrespective of either disease activity or treatment . Plasma endotoxins were detected in 12/71 (17%) patients with UC, and in 10/32 (31%) patients with CD . ANCA were present in 42/71 (59%) patients with UC and in 3/32 (9%) patients with CD, whereas anti-LF antibodies were detected in 31 (44%) UC patients and in six (19%) CD patients . No significant differences in phagocytosis and killing exerted by PMN were found between ANCA-positive and ANCA-negative UC patients . CONCLUSIONS: Our data demonstrate an impairment of natural immunity exerted by peripheral blood phagocytes and lymphocytes in patients with UC and CD . ANCA and anti-LF antibodies were present mainly in UC patients but their presence did not affect PMN-mediated phagocytosis and killing . Finally, plasma endotoxins may contribute to the chronic inflammatory status, likely by inducing release of proinflammatory mediators. Nature, 2000 Jul 6, 406(6791), 64 - 7 Parallel evolution of virulence in pathogenic Escherichia coli; Reid SD et al.; The mechanisms underlying the evolution and emergence of new bacterial pathogens are not well understood . To elucidate the evolution of pathogenic Escherichia coli strains, here we sequenced seven housekeeping genes to build a phylogenetic tree and trace the history of the acquisition of virulence genes . Compatibility analysis indicates that more than 70% of the informative sites agree with a single phylogeny, suggesting that recombination has not completely obscured the remnants of ancestral chromosomes . On the basis of the rate of synonymous substitution for E . coli and Salmonella enterica (4.7 x 10(-9) per site per year), the radiation of clones began about 9 million years ago and the highly virulent pathogen responsible for epidemics of food poisoning, E . coli O157:H7, separated from a common ancestor of E . coli K-12 as long as 4.5 million years ago . Phylogenetic analysis reveals that old lineages of E . coli have acquired the same virulence factors in parallel, including a pathogenicity island involved in intestinal adhesion, a plasmid-borne haemolysin, and phage-encoded Shiga toxins . Such parallel evolution indicates that natural selection has favoured an ordered acquisition of genes and the progressive build-up of molecular mechanisms that increase virulence. Vet Microbiol, 2000 Jul 31, 75(2), 155 - 65 Genotypic characterisation by PFGE of Salmonella enterica serotype Enteritidis phage types 1, 4, 6, and 8 isolated from animal and human sources in three European countries; Laconcha I et al.; A total of 101 strains of Salmonella Enteritidis phage types (PT) 1, 4, 6, and 8 from Denmark, England and Spain were studied by PFGE to elucidate genetic relationships among strains isolated from animal, human and environmental sources betwee