Publications

nose-to-nose transmission of salmonella typhimurium between weaned pigs.	little attention has been paid to the possibility of transmission of salmonella in intensive pig production systems through alternate methods, such as airborne or direct nose-to-nose contact. this experimental study tested the hypothesis of nose-to-nose transmission of salmonella enterica serovars typhimurium (trial i) and agona (trial ii) in weaned pigs using stainless steel/glass isolation cabinets. in each trial, cabinet 1 (control pigs) and cabinet 2 (sentinel pigs) were connected directly t ...	2007	17643873
potential management of resistant microbial infections with a novel non-antibiotic: the anti-inflammatory drug diclofenac sodium.	diclofenac sodium (dc), an anti-inflammatory agent, has remarkable inhibitory action both against drug-sensitive and drug-resistant clinical isolates of various gram-positive and gram-negative bacteria. the aim of this study was to determine the ability of dc to protect mice from a virulent salmonella infection. dc injected at 1.5 microg/g and 3.0 microg/g mouse body weight significantly protected animals from the lethality of salmonella infection. as was the case for the in vitro interaction, d ...	2007	17644318
bacteria-generated ptdins(3)p recruits vamp8 to facilitate phagocytosis.	salmonella enterica serovar typhimurium invades non-phagocytic cells by inducing macropinocytosis. sopb is involved in modulating actin dynamics to promote salmonella-induced invasion. we report here that sopb-generated ptdins(3)p binds vamp8/endobrevin to promote efficient bacterial phagocytosis. vamp8 is recruited to salmonella-induced macropinosomes in a nocodazole-dependent, but brefeldin a-independent, manner. we found that vamp8 directly binds to and colocalizes with ptdins(3)p. the inosit ...	2007	17645435
in vitro anaerobic incubation of salmonella enterica serotype typhimurium and laying hen cecal bacteria in poultry feed substrates and a fructooligosaccharide prebiotic.	the objective of this study was to investigate the effect of combining a prebiotic with poultry feeds on the growth of salmonella enterica serotype typhimurium (st) in an in vitro cecal fermentation system. cecal contents from three laying hens were pooled and diluted to a 1:3000 concentration in an anaerobic dilution solution. the cecal dilution was added to sterile test tubes filled with alfalfa and layer ration with and without fructooligosaccharide (fos). two controls containing cecal diluti ...	2007	17588782
the capsule encoding the viab locus reduces interleukin-17 expression and mucosal innate responses in the bovine intestinal mucosa during infection with salmonella enterica serotype typhi.	the viab locus contains genes for the biosynthesis and export of the vi capsular antigen of salmonella enterica serotype typhi. wild-type serotype typhi induces less cxc chemokine production in tissue culture models than does an isogenic viab mutant. here we investigated the in vivo relevance of these observations by determining whether the presence of the viab region prevents inflammation in two animal models of gastroenteritis. unlike s. enterica serotype typhimurium, serotype typhi or a serot ...	2007	17591794
mechanisms of salmonella entry into host cells.	salmonella enterica is an enteric bacterial pathogen that causes a variety of food and water-borne diseases ranging from gastroenteritis to typhoid fever. ingested bacteria colonize the intestinal epithelium by triggering their own phagocytosis, using a sophisticated array of effector proteins that are injected into the host cell cytoplasm through a type iii secretion apparatus. the synergistic action of these secreted effectors leads to a dramatic reorganization of the host actin cytoskeleton, ...	2007	17593246
quinolone resistance of salmonella enterica serovar virchow isolates from humans and poultry in israel: evidence for clonal expansion.	salmonella enterica serovar virchow is highly prevalent in humans and farm animals in israel. in addition to high rates of resistance to multiple antibiotics, this serovar exhibits a high incidence of resistance to nalidixic acid. more than 90% of salmonella serovar virchow isolates of human and poultry origin obtained from 1997 to 2004 were resistant to nalidixic acid (mic > or = 128 microg/ml), with reduced susceptibility to ciprofloxacin (mic between 0.125 and 0.250 microg/ml). most isolates ...	2007	17596371
type ivb pilus operon promoter controlling expression of the severe acute respiratory syndrome-associated coronavirus nucleocapsid gene in salmonella enterica serovar typhi elicits full immune response by intranasal vaccination.	attenuated salmonella enterica serovar typhi strains have been considered to be attractive as potential live oral delivery vector vaccines because of their ability to elicit the full array of immune responses in humans. in this study, we constructed an attenuated s. enterica serovar typhi strain stably expressing conserved nucleocapsid (n) protein of severe acute respiratory syndrome-associated coronavirus (sars-cov) by integrating the n gene into the pilv gene, which was under the control of th ...	2007	17596427
glutamine phosphoribosylpyrophosphate amidotransferase-independent phosphoribosyl amine synthesis from ribose 5-phosphate and glutamine or asparagine.	phosphoribosylamine (pra) is the first intermediate in the common pathway to purines and thiamine and is generated in bacteria by glutamine phosphoribosylpyrophosphate (prpp) amidotransferase (ec 2.4.2.14) from prpp and glutamine. genetic data have indicated that multiple, non-prpp amidotransferase mechanisms exist to generate pra sufficient for thiamine but not purine synthesis. here we describe the purification and identification of an activity (present in both escherichia coli and salmonella ...	2007	17686772
salmonella enterica serovar typhi ty21a expressing human papillomavirus type 16 l1 as a potential live vaccine against cervical cancer and typhoid fever.	human papillomavirus (hpv) vaccines based on l1 virus-like particles (vlps) can prevent hpv-induced genital neoplasias, the precursors of cervical cancer. however, most cervical cancers occur in developing countries, where the implementation of expensive vaccines requiring multiple injections will be difficult. a live salmonella-based vaccine could be a lower-cost alternative. we previously demonstrated that high hpv type 16 (hpv16)-neutralizing titers are induced after a single oral immunizatio ...	2007	17687110
concurrent infections in acute febrile illness patients in egypt.	we report the occurrence of concurrent infections with multiple acute febrile illness (afi) pathogens during an ongoing prospective laboratory-based surveillance in four infectious disease hospitals in urban and rural areas of egypt from june 2005 to august 2006. patients were screened for leptospira, rickettsia typhi, brucella, or salmonella enterica serogroup typhi by various methods including serology, culture, and pcr. one hundred eighty-seven of 1,510 patients (12.4%) evaluated had supporti ...	2007	17690420
the thiamine kinase (ycfn) enzyme plays a minor but significant role in cobinamide salvaging in salmonella enterica.	cobinamide (cbi) salvaging is impaired, but not abolished, in a salmonella enterica strain lacking a functional cobu gene. cobu is a bifunctional enzyme (ntp:adenosylcobinamide [ntp:adocbi] kinase, gtp:adenosylcobinamide-phosphate [gtp:adocbi-p] guanylyltransferase) whose adocbi kinase activity is necessary for cbi salvaging in this bacterium. inactivation of the ycfn gene in a deltacobu strain abrogated cbi salvaging. introduction of a plasmid carrying the ycfn(+) allele into a deltacobu deltay ...	2007	17693493
phopq-mediated regulation produces a more robust permeability barrier in the outer membrane of salmonella enterica serovar typhimurium.	the phopq two-component system of salmonella enterica serovar typhimurium produces a remodeling of the lipid a domain of the lipopolysaccharide, including the pagp-catalyzed addition of palmitoyl residue, the pmrab-regulated addition of the cationic sugar 4-aminoarabinose and phosphoethanolamine, and the lpxo-catalyzed addition of a 2-oh group onto one of the fatty acids. by using the diffusion rates of the dyes ethidium, nile red, and eosin y across the outer membrane, as well as the susceptibi ...	2007	17693506
recombining population structure of plesiomonas shigelloides (enterobacteriaceae) revealed by multilocus sequence typing.	plesiomonas shigelloides is an emerging pathogen that is widespread in the aquatic environment and is responsible for intestinal diseases and extraintestinal infections in humans and other animals. virtually nothing is known about its genetic diversity, population structure, and evolution, which severely limits epidemiological control. we addressed these questions by developing a multilocus sequence typing (mlst) system based on five genes (fusa, leus, pyrg, recg, and rpob) and analyzing 77 epid ...	2007	17693512
molecular characterization of the thi3 gene involved in thiamine biosynthesis in zea mays: cdna sequence and enzymatic and structural properties of the recombinant bifunctional protein with 4-amino-5-hydroxymethyl-2-methylpyrimidine (phosphate) kinase and thiamine monophosphate synthase activities.	a thiamine biosynthesis gene, thi3, from maize zea mays has been identified through cloning and sequencing of cdna and heterologous overexpression of the encoded protein, thi3, in escherichia coli. the recombinant thi3 protein was purified to homogeneity and shown to possess two essentially different enzymatic activities of hmp(-p) [4-amino-5-hydroxymethyl-2-methylpyrimidine (phosphate)] kinase and tmp (thiamine monophosphate) synthase. both activities were characterized in terms of basic kineti ...	2007	17696876
sopd acts cooperatively with sopb during salmonella enterica serovar typhimurium invasion.	the intracellular bacterial pathogen, salmonella enterica serovar typhimurium (s. typhimurium), causes disease in a variety of hosts. to invade and replicate in host cells, these bacteria subvert host molecular machinery using bacterial proteins, called effectors, which they translocate into host cells using specialized protein delivery systems. one of these effectors, sopd, contributes to gastroenteritis, systemic virulence and persistence of s. typhimurium in animal models of infection. recent ...	2007	17696999
molecular characterisation of multidrug-resistant salmonella enterica serovar typhimurium isolates from gomel region, belarus.	this study describes the characterisation by pulsed-field gel electrophoresis (pfge), multilocus variable number tandem repeat analysis (mlva) typing and antimicrobial resistance profiles of 35 salmonella enterica serovar typhimurium isolates, mostly from infections in children who acquired an infection outside hospitals in the gomel region of belarus. thirty-one isolates were highly similar according to pfge and mlva typing, were multidrug-resistant, including resistance to ceftiofur, and harbo ...	2007	17697002
identification of the salmonella enterica serotype typhimurium sipa domain responsible for inducing neutrophil recruitment across the intestinal epithelium.	in human intestinal disease induced by salmonella enterica serotype typhimurium (s. typhimurium) transepithelial migration of polymorphonuclear leukocytes (pmns) rapidly follows attachment of the bacteria to the epithelial apical membrane. previously, we have shown that the s. typhimurium effector protein, sipa, plays a pivotal role in signalling epithelial cell responses that lead to the transepithelial migration of pmns. thus, the objective of this study was to determine the functional domain ...	2007	17697195
regional ifngamma expression is insufficient for efficacious control of food-borne bacterial pathogens at the gut epithelial barrier.	ifngamma is critical for host defence against various food-borne pathogens including salmonella enterica and listeria monocytogenes, the causative agents of salmonellosis and listeriosis, respectively. we investigated the impact of regional ifngamma expression at the intestinal epithelial barrier on host invasion by salmonellae and listeriae following oral challenge. transgenic mice (ifngamma-gut), generated on an ifngamma knock-out (ko) background, selectively expressed ifngamma in the gut driv ...	2007	17698562
lipopolysaccharide from salmonella enterica activates nf-kappab through both classical and alternative pathways in primary b lymphocytes.	lipopolysaccharides (lps) are potent polyclonal b-lymphocyte activators. recently, we have shown that lps inhibits both spontaneous and drug-induced apoptosis in mature b lymphocytes, through cytosolic retention of bax, a proapoptotic protein of the bcl-2 family, by preventing its translocation to mitochondria. research within the last few years has revealed that members of the nf-kappab transcription factor regulate cell viability by activating genes involved in mitochondrion-dependent apoptosi ...	2007	17698569
constitutive acid sphingomyelinase enhances early and late macrophage killing of salmonella enterica serovar typhimurium.	we have identified acid sphingomyelinase (asm) as an important player in the early and late anti-salmonella activity of macrophages. a functional asm participated in the killing activity of macrophages against wild-type salmonella enterica serovar typhimurium. the role of asm in early macrophage killing of salmonella appears to be linked to an active nadph phagocyte oxidase enzymatic complex, since the flavoprotein inhibitor diphenyleneiodonium not only blocked a productive respiratory burst but ...	2007	17698574
comparative analysis of inchi2 plasmids carrying blactx-m-2 or blactx-m-9 from escherichia coli and salmonella enterica strains isolated from poultry and humans.	salmonella enterica bla(ctx-m-2) and bla(ctx-m-9) plasmid backbones from isolates from belgium and france were analyzed. the bla(ctx-m-2-)plasmids from both human and poultry isolates were related to the inchi2 papec-o1-r plasmid, previously identified in the united states in avian escherichia coli strains; the bla(ctx-m-9) plasmids were closely related to the inchi2 r478 plasmid.	2007	17698627
prevalence and characterization of extended-spectrum cephalosporin-resistant nontyphoidal salmonella isolates in adults in saint petersburg, russia (2002-2005).	we studied the prevalence of resistance to extended-spectrum cephalosporins (esc) among 1,078 salmonella enterica isolates collected from adults admitted to botkin hospital, st. petersburg, russia, for gastroenteritis between 2002 and 2005. only two esc-resistant isolates were detected, giving a low percentage of strains resistant to esc (0.2%). one multidrug-resistant (mdr) isolate of the virchow serotype produced a ctxm-3 extended-spectrum beta-lactamase (esbl). the bla(ctx-m-3) gene was locat ...	2007	17650961
prevalence, antimicrobial resistance, and extended-spectrum beta-lactamases characterization of salmonella isolates in apulia, southern italy (2001-2005).	the prevalence, antimicrobial susceptibility, and production of extended-spectrum beta-lactamases (esbls) of salmonella collected from several hospitals in apulia (southern italy) were evaluated. the most common salmonella isolates were salmonella enterica serovar typhimurium (44.6%), s. enterica serovar enteritidis (33.4 %), s. enterica serovar infantis (3.2 %), s. enterica serovar typhi (1.5%), and s. enterica serovar bovismorbificans (1.5%). the other serovars accounted for less than 1% each. ...	2007	17650965
complete nucleotide sequence of a small qnrs1-carrying plasmid from salmonella enterica subsp. enterica typhimurium dt193.		2007	17652106
geobacillus stearothermophilus lv cada gene mediates resistance to cadmium, lead and zinc in znta mutants of salmonella entérica serovar typhimurium.	salmonella entérica serovar typhimurium cells expressing the cada gene of geobacillus stearothermophilus lv exhibit a hypersensitive phenotype to cadmium chloride. deletion of the orf stm3576 from the salmonella genome resulted in cadmium, lead and zinc sensitivity, confirming that this orf is a homologue of the znta gene. the observed sensitivity was reverted upon expression of the g. stearothermophilus lv cada gene. these results indicate that the cada gene product is involved in cd, pb and zn ...	2007	17657347
characterization of the osmoprotectant transporter opuc from pseudomonas syringae and demonstration that cystathionine-beta-synthase domains are required for its osmoregulatory function.	the plant pathogen pseudomonas syringae may cope with osmotic stress on plants, in part, by importing osmoprotective compounds. in this study, we found that p. syringae pv. tomato strain dc3000 was distinct from most bacterial species in deriving greater osmoprotection from exogenous choline than from glycine betaine. this superior osmoprotection was correlated with a higher capacity for uptake of choline than for uptake of glycine betaine. of four putative osmoregulatory abc transporters in dc3 ...	2007	17660277
alterations in the two globular domains or in the connecting alpha-helix of bacterial ribosomal protein l9 induces +1 frameshifts.	the ribosomal 50s subunit protein l9, encoded by the gene rpli, is an elongated protein with an alpha-helix connecting the n- and c-terminal globular domains. we isolated rpli mutants that suppress the +1 frameshift mutation hisc3072 in salmonella enterica serovar typhimurium. these mutants have amino acid substitutions in the n-terminal domain (g24d) or in the c-terminal domain (i94s, a102d, g126v, and f132s) of l9. in addition, different one-base deletions in rpli altered either the final port ...	2007	17660285
mutations in yhit enable utilization of exogenous pyrimidine intermediates in salmonella enterica serovar typhimurium.	mutants capable of utilizing the pyrimidine biosynthetic intermediates carbamoylaspartate and dihydroorotate for growth were derived from pyrimidine auxotrophs of salmonella enterica serovar typhimurium lt2. the gain-of-function phenotypes both resulted from mutations in a single gene, yhit, the third gene of a putative four-gene operon, yhivuts, for which there is no homologous region in escherichia coli. notably, when a mutant yhit allele was transferred to a pyrimidine-requiring e. coli strai ...	2007	17660412
the escherichia coli arac-family regulators gadx and gadw activate gade, the central activator of glutamate-dependent acid resistance.	escherichia coli can survive ph 2 acid stress by using several acid resistance systems. the most efficient of these employs glutamate decarboxylase (gada/gadb) to consume protons, and an antiporter (gadc) to exchange the intracellular decarboxylation product for external glutamic acid. expression of the essential transcriptional activator of this system, gade, is controlled by several regulators in a hierarchical fashion. in this study, two additional activators have been identified. the arac-fa ...	2007	17660422
shigella flexneri phagosomal escape is independent of invasion.	infections with salmonella enterica serovar typhimurium and shigella flexneri result in mucosal inflammation in response to epithelial cell invasion and macrophage cytotoxicity. these processes are mediated by type iii secretion systems encoded in homologous virulence loci in the two species, namely, salmonella pathogenicity island 1 (spi-1), carried in the genome, and the shigella entry region (ser), carried in a large virulence plasmid. here we show that spi-1 can functionally complement a del ...	2007	17664266
i/st mice hypersusceptible to mycobacterium tuberculosis are resistant to m. avium.	we previously demonstrated that mice of the i/st strain are extremely susceptible to mycobacterium tuberculosis, as well as to the taxonomically distant intracellular bacteria chlamydia pneumoniae and salmonella enterica. to broaden our knowledge about the control of susceptibility to intracellular pathogens, we studied the infection caused by mycobacterium avium virulent strain 724 in a panel of inbred mouse strains and found that i/st mice are resistant to m. avium. by comparing i/st mice with ...	2007	17664269
a proteomic approach to study salmonella enterica serovar typhimurium putative transporter yjeh associated with ceftriaxone resistance.	mutant 6b7 of salmonella enterica serovar typhimurium has a transposon inserted in the putative transporter gene yjeh and shows a more-than-fourfold reduction in resistance to ceftriaxone. in this report we have used proteomic analysis to compare outer membrane protein profiles between this mutant and its parental strain r200. five identified proteins were found to be altered. of these proteins, the level of expression of the porin ompd was increased and those of the putative outer membrane prot ...	2007	17669360
role of nucleoid-associated proteins hha and h-ns in expression of salmonella enterica activators hild, hilc, and rtsa required for cell invasion.	the coordinate expression of salmonella enterica invasion genes on salmonella pathogenicity island 1 is under the control of the complex circuits of regulation that involve the arac/xyls family transcriptional activators hild, hilc, and rtsa and nucleoid-associated proteins. single-copy transcription fusions were used to assess the effects of nucleoid-associated proteins hha and h-ns on hild, hilc, and rtsa expression. the data show that all three genes, hild, hilc, and rtsa, were repressed by h ...	2007	17675384
isolation of salmonella enterica serovar enteritidis from houseflies (musca domestica) found in rooms containing salmonella serovar enteritidis-challenged hens.	houseflies (musca domestica) released into rooms containing hens challenged with salmonella enterica serovar enteritidis (salmonella serovar enteritidis) rapidly became contaminated with salmonella serovar enteritidis. forty to 50% of the flies were contaminated at 48 h, and the percentage increased to 50 to 70% at 4 and 7 days postexposure and then decreased to 30% at day 15. initial attempts at recovering surface organisms for culture using an aqueous rinse were largely unsuccessful, while cul ...	2007	17675422
cloning and transfer of the salmonella pathogenicity island 2 type iii secretion system for studies of a range of gram-negative genera.	the engineering of bacterial strains with specific phenotypes frequently requires the use of blocks or "cassettes" of genes that act together to perform a desired function. the potential benefits of utilizing type iii secretion systems in this regard are becoming increasingly realized since these systems can be used to direct interactions with host cells for beneficial purposes such as vaccine development, anticancer therapies, and targeted protein delivery. however, convenient methods to clone ...	2007	17675443
icsbp1/irf-8 is required for innate and adaptive immune responses against intracellular pathogens.	the chronic myeloid leukemia syndrome of the bxh-2 mouse strain (mus musculus) is caused by a recessive mutation (r294c) in the transcriptional regulator icsbp1/irf-8. in trans activation assays using an il-12p40 gene reporter construct introduced in raw 264.7 mouse macrophages, we show that the icsbp1(c294) isoform behaves as a partial loss-of-function. the icsbp1(c294) hypomorph allele appears to have a threshold effect on il-12 production, with pleiotropic consequences on resistance to differ ...	2007	17675508
global gene expression profile after salmonella enterica serovar enteritidis challenge in two f8 advanced intercross chicken lines.	a chicken 13k cdna microarray was used to profile global gene expression after salmonella enteritidis (se) challenge of young chickens. two f8 advanced intercross lines (ail), broiler by leghorn, and broiler by fayoumi, were studied. day-old chicks were orally inoculated with se, and spleens were harvested at day 7 or 8 post-inoculation. the se bacteria burden in the spleen was quantified. the 20% high and 20% low se burden birds within each ail and harvest time were studied by microarray. the l ...	2007	17675853
susceptibility of germ-free pigs to challenge with protease mutants of salmonella enterica serovar typhimurium.	salmonella protease mutants, clpp and especially htra, are candidate live oral vaccines in humans. a functional and mature immune system is, however, required to cope with them in mice. here, we test the cytokine response of highly susceptible germ-free pigs to infection with salmonella typhimurium clpp and htra mutants. cytokine levels (il-4, il-10, il-18 and ifn-gamma) were measured by elisa in plasma and washes from the terminal small bowel 24h after oral challenge. unlike the infection with ...	2007	17678715
immune complex-induced enhancement of bacterial antigen presentation requires fcgamma receptor iii expression on dendritic cells.	dendritic cells (dcs) are capable of initiating adaptive immune responses against infectious agents by presenting pathogen-derived antigens on mhc molecules to naïve t cells. because of their key role in priming adaptive immunity, it is expected that interfering with dc function would be advantageous to the pathogen. we have previously shown that salmonella enterica serovar typhimurium (st), is able to survive inside dcs and interfere with their function by avoiding activation of bacteria-specif ...	2007	17679697
oral infection of mice with salmonella enterica serovar typhimurium causes meningitis and infection of the brain.	salmonella meningitis is a rare and serious infection of the central nervous system following acute salmonella enterica sepsis. for this pathogen, no appropriate model has been reported in which to examine infection kinetics and natural dissemination to the brain.	2007	17597539
sigma(s)-dependent carbon-starvation induction of pbpg (pbp 7) is required for the starvation-stress response in salmonella enterica serovar typhimurium.	carbon-energy source starvation is a commonly encountered stress that can influence the epidemiology and virulence of salmonella enterica serovars. salmonella responds to c-starvation by eliciting the starvation-stress response (ssr), which allows for long-term c-starvation survival and cross-resistance to other stresses. the stic locus was identified as a c-starvation-inducible, sigma(s)-dependent locus required for a maximal ssr. we report here that the stic locus is an operon composed of the ...	2007	17600059
a group of escherichia coli and salmonella enterica o antigens sharing a common backbone structure.	the o-antigen moiety of the lps is one of the most variable cell surface components of the gram-negative bacterial outer membrane. variation is due to the presence of different sugars and sugar linkages. here, it is reported that a group of escherichia coli o serogroups (o17, o44, o73, o77 and o106), and the salmonella enterica serogroup o : 6,14 (h), share a common four-sugar backbone o-subunit structure, and possess almost identical o-antigen gene clusters. whereas the e. coli o77 antigen does ...	2007	17600060
positive adaptive state: microarray evaluation of gene expression in salmonella enterica typhimurium exposed to nalidixic acid.	the emergence of antimicrobial resistance among foodborne bacteria associated with food animal production is an important global issue. we hypothesised that antibiotics generate a positive adaptive state in salmonella that actively contributes to the development of antimicrobial resistance. this is opposed to common views that antimicrobials only act as a passive selective pressure. microarray analysis was used to evaluate changes in gene expression that occur upon exposure of salmonella enteric ...	2007	17600486
construction and evaluation of a microbiological positive process internal control for pcr-based examination of food samples for listeria monocytogenes and salmonella enterica.	pcr assays for food-borne pathogens are widely available but have had more limited application to food testing compared with their use in clinical laboratories. when testing food samples, false negative pcr results can occur and may be due to interference with target-cell lysis necessary for nucleic acid extraction, nucleic acid degradation and/or direct inhibition of the pcr. therefore, it is essential to include appropriate controls for the application of pcr to the detection of pathogens in f ...	2007	17604864
comparison of salmonella enterica serovar heidelberg susceptibility testing results.	disk diffusion and broth dilution assays are conventionally used for antimicrobial susceptibility testing (ast) of bacteria. the goal of this study was to determine the correlation of results from different ast methods for the salmonella enterica serovar heidelberg.	2007	17607044
bacterial-induced hepoxilin a3 secretion as a pro-inflammatory mediator.	bacterial infections at epithelial surfaces, such as those that line the gut and the lung, stimulate the migration of neutrophils through the co-ordinated actions of chemoattractants secreted from pathogen-stimulated epithelial cells. one such factor involved in attracting polymorphonuclear leukocytes across the epithelium and into the lumen has until recently remained elusive. in 2004, we identified the eicosanoid, hepoxilin a(3), to be selectively secreted from the apical surface of human inte ...	2007	17608718
a small rna downregulates lamb maltoporin in salmonella.	in escherichia coli and salmonella enterica, activation of sigma(e)-dependent envelope stress response leads to the abrupt decline in the synthesis of all major outer membrane proteins (omps). recent studies found that two sigma(e)-controlled small rnas (srnas), mica and rybb, downregulate a number of omps. while rybb targets several different mrnas, including ompc and ompd, mica was up to date thought to act solely on ompa. here we present evidence showing that mica downregulates a second salmo ...	2007	17608792
stability of multiple-locus variable-number tandem repeats in salmonella enterica serovar typhimurium.	variable-number tandem repeats (vntrs) may evolve so rapidly that multiple profiles emerge during an outbreak. a total of 190 isolates from eight salmonella enterica serovar typhimurium outbreaks and 15 isolates from seven patients were analyzed by pulsed-field gel electrophoresis and vntr typing. small changes in loci were noted; otherwise, the vntr profiles were stable during the course of the outbreaks.	2007	17609320
genotypes, serotypes, and antibiotic resistance profiles of salmonella isolated from commercial north carolina turkey farms.	this study was designed to determine the serotypes, genotypes, and antibiotic resistance (abr) patterns of 42 salmonella isolates recovered from either fecal or litter samples of 12 commercial turkey farms across two seasons (summer and winter) and two ages (3 and 19 weeks). isolates were serotyped on the basis of the kauffmann-white scheme. genotyping was done by restriction digestion of cdna (xbai) and subsequent pulsed-field gel electrophoresis (pfge). the abr was determined with sensititre s ...	2007	17612059
surveillance and antimicrobial resistance of salmonella strains isolated from slaughtered pigs in spain.	the prevalence of and the antibiotic resistance shown by salmonella isolated from pigs in andalusia (southern spain) is reported. salmonella enterica was recovered from 40 (33%) of 121 sampled herds, and a total of 65 isolates were serotyped. the most common salmonella serotypes were typhimurium and rissen (30.7% each); others included derby (9.2%), brandenburg (9.2%), newport (7.7%), bredeney (4.6%), anatum (3.0%), hadar (1.5%), and goldcoast (1.5%). one strain (1.5%) belonging to the monophasi ...	2007	17612084
inactivation kinetics of inoculated escherichia coli o157:h7, listeria monocytogenes and salmonella enterica on strawberries by chlorine dioxide gas.	inactivation kinetics of inoculated escherichia coli o157:h7, listeria monocytogenes and salmonella enterica on strawberries by chlorine dioxide gas at different concentrations (0.5, 1, 1.5, 3 and 5 mgl(-1)) for 10 min were studied. a cocktail of three strains of each targeted organism (100 microl) was spotted onto the surface of the strawberries (approximately 8-9 log ml(-1)) separately followed by air drying, and then treated with clo(2) gas at 22 degrees c and 90-95% relative humidity. approx ...	2007	17613371
survival of escherichia coli o157:h7 and salmonella enterica serovars typhimurium in iceberg lettuce and the antimicrobial effect of rice vinegar against e. coli o157:h7.	the microbiological safety of fresh produce is a significant concern of consumers and industry. after applying at an inoculated level (about 10(6) cfug(-1)) of e. coli o157:h7 and salmonella enterica serovars typhimurium on shredded iceberg lettuce and water samples individually, they were stored at 4 degrees c for 14 days and 22 degrees c for 7 days to monitor the growth and survival of pathogens. the results showed that at the end of 4 degrees c storage, populations of two pathogens in lettuce ...	2007	17613372
the influence of attachment to beef surfaces on the survival of cells of salmonella enterica serovar typhimurium dt104, at different a(w) values and at low storage temperatures.	this study investigated the influence of attachment to beef surfaces on the survival, injury and death of stationary phase cells of salmonella enterica serovar typhimurium dt104, compared to cells free in solution. the effects on cells are considered at different a(w) values and low temperatures in relation to osmotic and cold temperature shock effects. attachment of cells to meat surfaces prevented cell injury and death from hyperosmosis and low temperatures, compared to meat solutions. storage ...	2007	17613377
salmonella enterica serotype urbana interference with brucellosis serology.	sheep were immunized with killed salmonella enterica serotype urbana cells and their sera were tested in various serological tests for antibody to brucella sp., yersinia enterocolitica o:9 and escherichia coli o:157 h:7. of the eight sheep, all gave a positive agglutination reaction in the brucellosis buffered antigen plate agglutination test (bpat), seven gave positive brucellosis standard tube agglutination test (tat) and complement fixation test (cft) results and four gave slightly positive r ...	2007	17613674
nucleoside analogues are activated by bacterial deoxyribonucleoside kinases in a species-specific manner.	to investigate the bactericidal activity of antiviral and anticancer nucleoside analogues against a variety of pathogenic bacteria and characterize the activating enzymes, deoxyribonucleoside kinases (dnks).	2007	17615154
salmonella enterica serovar typhimurium regulates intercellular junction proteins and facilitates transepithelial neutrophil and bacterial passage.	the establishment of tight junctions (tj) between columnar epithelial cells defines the functional barrier, which enteroinvasive pathogens have to overcome. salmonella enterica serovar typhimurium (s. typhimurium) directly invades intestinal epithelial cells but it is not well understood how the pathogen is able to overcome the intestinal barrier and gains access to the circulation. therefore, we sought to determine whether infection with s. typhimurium could regulate the molecular composition o ...	2007	17615177
a connector of two-component regulatory systems promotes signal amplification and persistence of expression.	organisms rely on a variety of regulatory architectures to control gene transcription. whereas the functional characteristics of particular architectures are well understood, the properties of newly discovered regulatory designs cannot be easily predicted. one emerging design depends on small proteins that connect two-component regulatory systems, which constitute the dominant form of bacterial signal transduction. these connectors enable one system to respond to the signal perceived by a differ ...	2007	17615238
antimicrobial susceptibility patterns of salmonella enterica serotype typhi in eastern nepal.	the aim of the present study was to evaluate antimicrobial susceptibility patterns with special reference to multidrug resistance, susceptibility to ciprofloxacin, and bacteriophage typing of salmonella enterica serotype typhi isolated from blood sent for culture in a tertiary-care teaching hospital in eastern nepal during january 2000-december 2004. in total, 132 strains of s. enterica typhi, isolated from 2,568 blood culture samples collected from cases of suspected enteric fever, were tested ...	2007	17615907
rcs and phopq regulatory overlap in the control of salmonella enterica virulence.	genetic screens based on the use of mudj-generated lac fusions permitted the identification of novel genes regulated by the rcs signal transduction system in salmonella enterica serovar typhimurium. besides genes that are also found in the escherichia coli genome, our screens identified salmonella-specific genes regulated by rcsb, including bapa, siie, srfa, and srfb. here we show that the srfabc operon is negatively regulated by rcsb and by phop. in vivo studies using mutants with constitutive ...	2007	17616593
the ompw (porin) gene mediates methyl viologen (paraquat) efflux in salmonella enterica serovar typhimurium.	porins are channels that enable passive diffusion of hydrophilic solutes, nutrients and toxins through the outer bacterial membrane. this explains in part the ability of gram-negative microorganisms to grow in several different environments, as well as their drug resistance. ompd is an outer membrane channel that works with the inner membrane pump yddg to expel methyl viologen (mv) from salmonella enterica serovar typhimurium; this occurs independently of smva, also involved in mv resistance. on ...	2007	17618087
salmonella pseudomembranous colitis.	pseudomembranous colitis is most often associated with antibiotic use and caused most often by clostridium difficile. aclinical syndrome and pathology that is identical can be caused rarely by other organisms. we report a case of salmonella enterica pseudomembranous colitis and briefly review the literature regarding rare causes of this syndrome.	2007	17619469
role of gene 10 protein in the hierarchical assembly of the bacteriophage p22 portal vertex structure.	the portal vertex structure of the phage p22 is a 2.8 mda molecular machine that mediates attachment and injection of the viral genome into the host salmonella enterica serovar typhimurium. five proteins form this molecular machine: the portal protein, gp1; the tail-spike, gp9; the tail-needle, gp26, and the tail accessory factors, gp4 and gp10. in order to understand the assembly of the portal vertex structure, we have isolated the gene encoding tail accessory factor gp10 and defined its struct ...	2007	17620013
implication of quorum sensing in salmonella enterica serovar typhimurium virulence: the luxs gene is necessary for expression of genes in pathogenicity island 1.	despite the fact that the regulatory system sensing density of cell population and its signaling molecule have been identified in salmonella enterica, the biological significance of this phenomenon termed as quorum sensing remains unknown. in this report, we provide evidence that the luxs gene is necessary for salmonella virulence phenotypes. transcription assays showed that the cell-density-dependent induction of the invf gene was abolished in a salmonella strain with the luxs gene deleted. the ...	2007	17620352
investigation on the agonistic and antagonistic biological activities of synthetic chlamydia lipid a and its use in in vitro enzymatic assays.	the synthetic 1,4'-bisphosphorylated penta-acyl and tetra-acyl lipid a structures representing the major molecular species of natural chlamydial lipid a were tested for their endotoxic activities as measured by interleukin-8 release from human embryonic kidney (hek) 293 cells expressing toll-like receptor (tlr) 2 or tlr4. both compounds were unable to activate hek293 cells transiently transfected with tlr2. the penta-acyl lipid a was a weak activator of hek293 cells expressing tlr4/md-2/cd14 whe ...	2007	17621554
effects of salmonella enterica subsp. enterica serovar enteritidis vaccination in layer hens subjected to s. enteritidis challenge and various feed withdrawal regimens.	levels of salmonella enterica subsp. enterica serovar enteritidis infection and serum s. enteritidis antibodies after experimental s. enteritidis challenge and feed withdrawal were investigated in s. enteritidis-vaccinated and unvaccinated hens. the results were used to determine whether formalin-inactivated s. enteritidis vaccination can protect layer hens from s. enteritidis challenge during feed withdrawal periods. s. enteritidis infection rates were evaluated from cloacal swabs, eggs and org ...	2007	17624693
chicken gallinacin gene cluster associated with salmonella response in advanced intercross line.	salmonella enterica serovar enteritidis is a gram-negative bacterium that negatively affects human and animal health. many eukaryotes use antimicrobial peptides (alpha-defensins, beta-defensins, gamma-defensins, and cathelicidins) in innate immune responses to fight bacterial infections. poultry gallinacins are the functional equivalents of mammalian beta-defensins. two related advanced intercross lines of chickens were analyzed for association of gallinacin genotypic variation with salmonella e ...	2007	17626484
molting in salmonella enteritidis-challenged laying hens fed alfalfa crumbles. i. salmonella enteritidis colonization and virulence gene hila response.	the objectives of this study were to enumerate salmonella enterica serovar enteritidis colonization in fecal, cecal, and internal organs, and to compare the level of virulence gene expression (hila) of experimentally challenged laying hens fed different dietary molt-induction regimens. twelve salmonella-free single comb leghorn hens (>50 wk old) hens were randomly assigned to each of 6 treatment groups designated based on diet in 2 trials: 1) feed withdrawal salmonella enteritidis-positive (fw+) ...	2007	17626806
assessing the prevalence of salmonella enterica in poultry hatcheries by using hatched eggshell membranes.	salmonella enterica causes a number of significant poultry diseases and is also a major pathogen in humans. most poultry infected by salmonella become carriers; infection may also be fatal, depending on the particular serovar and the age of the bird at infection. younger birds are more susceptible to infection by salmonella, so it is critical that hatcheries monitor birds. we developed a method to use hatched eggshell membranes (hem) to assess contamination by salmonella in poultry hatching cabi ...	2007	17626809
gene promoter scan methodology for identifying and classifying coregulated promoters.	a critical challenge of the postgenomic era is to understand how genes are differentially regulated. genetic and genomic approaches have been used successfully to assign genes to distinct regulatory networks in both prokaryotes and eukaryotes. however, little is known about what determines the differential expression of genes within a particular network, even when it involves a single transcription factor. the fact that coregulated genes may be differentially expressed suggests that subtle diffe ...	2007	17628149
phosphorylation assays of chemotaxis two-component system proteins in borrelia burgdorferi.	borrelia burgdorferi has a complex chemotaxis signal transduction system with multiple chemotaxis gene homologs similar to those found in escherichia coli and bacillus subtilis. the b. burgdorferi genome sequence encodes two chea, three chey, three chew, two cheb, two cher, but no chez genes. instead of chez, b. burgdorferi contains a different chey-p phosphatase, referred to as chex. the multiple b. burgdorferi histidine kinases (chea1 and chea2) and response regulators (chey1, chey2, and chey3 ...	2007	17628153
core-linked lps expression of shigella dysenteriae serotype 1 o-antigen in live salmonella typhi vaccine vector ty21a: preclinical evidence of immunogenicity and protection.	shigella dysenteriae serotype 1 (s. dysenteriae 1) causes severe shigellosis that is typically associated with high mortality. antibodies against shigella serotype-specific o-polysaccharide (o-ps) have been shown to be host protective. in this study, the rfb locus and the rfp gene with their cognate promoter regions were pcr-amplified from s. dysenteriae 1, cloned, and sequenced. deletion analysis showed that eight rfb orfs plus rfp are necessary for biosynthesis of this o-ps. a tandemly-linked ...	2007	17629369
emergence of multidrug-resistant salmonella enterica serovar typhi associated with a class 1 integron carrying the dfra7 gene cassette in nepal.	a total of 121 salmonella enterica serovars typhi and paratyphi a isolated from enteric fever patients at a university hospital in nepal between february 2004 and january 2006 were tested for their antimicrobial susceptibility. the occurrence and cassette content of integrons as well as the molecular mechanisms of resistance among the multidrug-resistant (mdr) s. typhi were evaluated. thirty-nine percent of the isolates were susceptible to all the antimicrobial agents tested. seven of the s. typ ...	2007	17629465
tricarballylate catabolism in salmonella enterica. the tcub protein uses 4fe-4s clusters and heme to transfer electrons from fadh2 in the tricarballylate dehydrogenase (tcua) enzyme to electron acceptors in the cell membrane.	tricarballylate, a citrate analogue, is considered the causative agent of grass tetany, a ruminant disease characterized by acute magnesium deficiency. although the normal rumen flora cannot catabolize tricarballylate, the gram-negative enterobacterium salmonella enterica can. an operon dedicated to tricarballylate utilization (tcuabc) present in this organism encodes all functions required for tricarballylate catabolism. tricarballylate is converted to the cis-aconitate in a single oxidative st ...	2007	17630784
isolation of salmonella enterica serotype newport from a partly ruptured splenic abscess in a traveler returning from zanzibar.	salmonella enterica subsp. enterica serotype newport is a pathogen of growing importance because of its epidemic spread in dairy cattle and increasing rate of antimicrobial resistance. human infections, however, are rare. we report a case of a splenic abscess in a young traveler returning from east africa.	2007	17634302
multiplex, bead-based suspension array for molecular determination of common salmonella serogroups.	we report the development and evaluation of a salmonella o-group-specific bio-plex assay to detect the six most common serogroups in the united states (b, c(1), c(2), d, e, and o13) plus serotype paratyphi a. the assay is based on rfb gene targets directly involved in o-antigen biosynthesis; it can be completed 45 min post-pcr amplification. the assay correctly and specifically identified 362 of 384 (94.3%) isolates tested in comparison to traditional serotyping. seventeen isolates (4.4%) produc ...	2007	17634307
salmonella pathogenicity island 4-mediated adhesion is coregulated with invasion genes in salmonella enterica.	salmonella pathogenicity island 4 (spi4) encodes a type i secretion system and the cognate substrate protein, siie. we have recently demonstrated that siie is a giant nonfimbrial adhesin involved in the adhesion of salmonella enterica serovar typhimurium to polarized epithelial cells. we also observed that under in vitro culture conditions, the synthesis and secretion of siie coincided with the activation of salmonella invasion genes. these observations prompted us to investigate the regulation ...	2007	17635868
plasmid-mediated quinolone resistance determinant qnrs1 detected in salmonella enterica serovar corvallis strains isolated in denmark and thailand.		2007	17635876
the effect of methylation on dna replication in salmonella enterica serovar typhimurium.	the dna adenine methylase of salmonella typhimurium methylates adenine at gatc sequences. strains deficient in this methylase are not well transformed by methylated plasmids, but unmethylated plasmids transform them at high frequencies. hemimethylated daughter molecules accumulate after the transformation of dam(-) strains with fully methylated plasmids, suggesting that hemimethylation prevents dna replication. it will also be shown that plasmids isolated from dam(-) bacteria are hemimethylated ...	2007	17637438
cloning, nucleotide sequencing, and analysis of the acrab-tolc efflux pump of enterobacter cloacae and determination of its involvement in antibiotic resistance in a clinical isolate.	enterobacter cloacae is an emerging clinical pathogen that may be responsible for nosocomial infections. management of these infections is often difficult, owing to the high frequency of strains that are resistant to disinfectants and antimicrobial agents in the clinical setting. multidrug efflux pumps, especially those belonging to the resistance-nodulation-division family, play a major role as a mechanism of antimicrobial resistance in gram-negative pathogens. in the present study, we cloned a ...	2007	17638702
a multiplex polymerase chain reaction method for rapid identification of citrobacter freundii and salmonella species, including salmonella typhi.	salmonella enterica is one of the most common enteric pathogens worldwide. conventional methods of isolation of salmonella strains take 4-7 days to complete, are laborious and require substantial manpower. we devised a polymerase chain reaction (pcr) method that simultaneously uses three pairs of specific primers to detect inv, spv, and via genes of salmonella.	2007	17639162
change of serotype pattern of group d non-typhoidal salmonella isolated from pediatric patients in southern taiwan.	group d non-typhoidal salmonella infection is increasing in taiwan. this study aimed to investigate the changing serotypes and antibiotic resistance of childhood group d salmonella infection.	2007	17639164
extraintestinal focal infections in adults with salmonella enterica serotype choleraesuis bacteremia.	salmonella enterica serotype choleraesuis, which is associated with severe human infections and multidrug resistance, poses a serious problem in taiwan. the aim of the study was to investigate the epidemiology and clinical features of s. choleraesuis bacteremia.	2007	17639165
gas-forming splenic abscess due to salmonella enterica serotype enteritidis in a chronically hemodialyzed patient.	we describe a diabetic patient who was chronically hemodialyzed due to end-stage renal disease and developed a gas-forming splenic abscess and bacteremia caused by salmonella enterica serotype enteritidis. fever persisted despite urgent splenectomy and intravenous ceftriaxone and metronidazole for 14 days. he recovered completely after intravenous ciprofloxacin/metronidazole treatment for a further 14 days. the isolate was susceptible to ciprofloxacin and ceftriaxone and did not exhibit extended ...	2007	17639171
comparison of salmonella enterica serotype infantis isolates from a veterinary teaching hospital.	to compare salmonella enterica serotype infantis isolates obtained from patients or the environment of a veterinary teaching hospital over a period of 9 years following a nosocomial outbreak to determine whether isolates were epidemiologically related or represented unrelated introductions into the hospital environment.	2007	17578417
the spi-2 type iii secretion system restricts motility of salmonella-containing vacuoles.	intracellular replication of salmonella enterica occurs in membrane-bound compartments, called salmonella-containing vacuoles (scvs). following invasion of epithelial cells, most scvs migrate to a perinuclear region and replicate in close association with the golgi network. the association of scvs with the golgi is dependent on the salmonella-pathogenicity island-2 (spi-2) type iii secretion system (t3ss) effectors sseg, ssef and sifa. however, little is known about the dynamics of scv movement. ...	2007	17578517
effect of dietary beta1-4 mannobiose in the prevention of salmonella enteritidis infection in broilers.	1. this study investigated the effects of beta1-4 mannobiose (mnb)-supplemented feeds on the kinetics of salmonella enterica serovar enteritidis (se) in broilers and the ensuing histopathological changes. d-mannose (man) was used for comparison. the diets supplemented with mnb or man were fed during the first two weeks after hatching to investigate any protection against se infection in growing birds and any immunomodulatory functions in the gut. 2. mnb-supplementation reduced se organ colonisat ...	2007	17578696
cutting edge: natural dna repetitive extragenic sequences from gram-negative pathogens strongly stimulate tlr9.	bacterial dna exerts immunostimulatory effects on mammalian cells via the intracellular tlr9. although broad analysis of tlr9-mediated immunostimulatory potential of synthetic oligonucleotides has been developed, which kinds of natural bacterial dna sequences are responsible for immunostimulation are not known. this work provides evidence that the natural dna sequences named repetitive extragenic palindromic (reps) sequences present in gram-negative bacteria are able to produce innate immune sys ...	2007	17579017
precollaborative study of the genequence salmonella assay using 24-hour enrichment protocols for detection of salmonella spp. in select foods.	new enrichment protocols are described for use with a dna hybridization (dnah) method for detection of salmonella spp. in select foods. genequence salmonella, in its original version, utilized a 3-stage enrichment of minimum 42 h duration. new 2-stage procedures of 24-28 h duration are described for raw poultry, raw beef, pasteurized egg products, milk chocolate, and dry pet food. in the validation study described here, a total of 345 samples were tested by the abbreviated dnah method in paralle ...	2007	17580626
evaluation of the genequence dna hybridization method in conjunction with 24-hour enrichment protocols for detection of salmonella spp. in select foods: collaborative study.	a multilaboratory study was conducted to compare performance of the genequence dna hybridization (dnah) method incorporating new 24 h enrichment protocols and reference culture procedures for detection of salmonella spp. in select foods. six food types (raw ground turkey, raw ground beef, dried whole egg, milk chocolate, walnuts, and dry pet food) were tested by the dnah method and by the culture methods of either the u.s. department of agriculture-food safety and inspection service (usda-fsis) ...	2007	17580627
c-reactive protein collaborates with plasma lectins to boost immune response against bacteria.	although human c-reactive protein (crp) becomes upregulated during septicemia, its role remains unclear, since purified crp showed no binding to many common pathogens. contrary to previous findings, we show that purified human crp (hcrp) binds to salmonella enterica, and that binding is enhanced in the presence of plasma factors. in the horseshoe crab, carcinoscorpius rotundicauda, crp is a major hemolymph protein. incubation of hemolymph with a range of bacteria resulted in crp binding to all t ...	2007	17581635
cell-mediated immunity and antibody responses elicited by attenuated salmonella enterica serovar typhi strains used as live oral vaccines in humans.	the development of improved typhoid vaccines is a high global public health priority. however, their development has been hampered by a lack of information regarding the specific determinants of protective immunity to salmonella enterica serovar typhi (s. typhi) infection in humans. although antibodies to s. typhi o, h, and vi appear to be involved in protection against s. typhi infection, it is unknown whether such antibodies mediate protection, act in conjunction with other adaptive responses, ...	2007	17582562
cvd 908, cvd 908-htra, and cvd 909 live oral typhoid vaccines: a logical progression.	typhoid fever remains an important public health problem in many parts of the world. despite the availability of oral ty21a (vivotif; berna biotech) and parenteral vi polysaccharide vaccine (typhim vi; aventis pasteur), improved typhoid fever vaccines have been sought. these include a series of vaccine candidates developed at the center for vaccine development, university of maryland, based on attenuation of salmonella enterica serovar typhi by deletions in the aroc, arod, and htra genes. these ...	2007	17582563
ty21a live oral typhoid vaccine and prevention of paratyphoid fever caused by salmonella enterica serovar paratyphi b.	in randomized, controlled field trials in area norte and area occidente of santiago, chile, 2 (norte) or 3 (occidente) doses of live oral typhoid vaccine ty21a in enteric-coated capsules conferred protection against confirmed salmonella enterica serovar typhi disease (53% efficacy in norte; 67% efficacy in occidente) during 3 years of follow-up. there was also a trend in each trial showing protection against s. enterica serovar paratyphi b disease (56% efficacy in norte; 42% efficacy in occident ...	2007	17582564
the genome of salmonella enterica serovar typhi.	the generation of complete genome sequences provides a blueprint that facilitates the genetic characterization of pathogens and their hosts. the genome of salmonella enterica serovar typhi (s. typhi) harbors ~5 million base pairs encoding some 4000 genes, of which >200 are functionally inactive. comparison of s. typhi isolates from around the world indicates that they are highly related (clonal) and that they emerged from a single point of origin ~30,000-50,000 years ago. evidence suggests that, ...	2007	17582565
a personal perspective on clinical research in enteric fever.	with the global spread of enteric fever, the emergence of salmonella enterica serovar paratyphi as a major pathogen (particularly in asia), the spread of drug resistance, and the global increase in the incidence of non-typhi salmonella, particularly in patients coinfected with human immunodeficiency virus, there is now more than ever a need for clinical research in enteric fever. the work of ted woodward 60 years ago remains relevant today, and his holistic approach to clinical research inspired ...	2007	17582579
t cell immunity evasion by virulent salmonella enterica.	salmonella enterica are gram-negative bacteria that cause systemic disease in their specific hosts. one of the recently appreciated features of salmonella pathogenicity is the capacity of the bacteria to impair host adaptive immunity by interfering with dc function and t cell activation. it is likely that this feature of virulent salmonella is needed to promote systemic dissemination in the host. recent studies have suggested explanations for some of the molecular mechanisms developed by virulen ...	2007	17583359
[outbreak of gastroenteritis in a nursery school caused by a strain of salmonella enterica serovar typhimurium carrying the hybrid virulence-resistance plasmid puo-stvr2].	epidemiological and microbiological study of a salmonellosis outbreak, affecting 22 children in a nursery school in oviedo (spain).	2007	17583650
inactivation of salmonella senftenberg strain w 775 during composting of biowastes and garden wastes.	determination of the minimum requirements (time-temperature relationship and moisture content) that are needed for a sufficient eradication of an indicator organism.	2007	17584452
tbk1 protects vacuolar integrity during intracellular bacterial infection.	tank-binding kinase-1 (tbk1) is an integral component of type i interferon induction by microbial infection. the importance of tbk1 and type i interferon in antiviral immunity is well established, but the function of tbk1 in bacterial infection is unclear. upon infection of murine embryonic fibroblasts with salmonella enterica serovar typhimurium (salmonella), more extensive bacterial proliferation was observed in tbk1(-/-) than tbk1(+/+) cells. tbk1 kinase activity was required for restriction ...	2007	17335348