Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| salmonella resistant to extended-spectrum cephalosporins: prevalence and epidemiology. | salmonella resistant to extended-spectrum cephalosporins (escs) have emerged worldwide since 1988. by 2004, 43 countries had reported this public health problem. resistance was mediated by classical extended-spectrum beta-lactamases, plasmid-mediated cephalosporinases, and recently a class a carbapenemase. of these, cmy-2 is the most widely disseminated enzyme. salmonella enterica serotype typhimurium and s. enterica serotype enteritidis are the most common serovars associated with esc resistanc ... | 2006 | 16714134 |
| emergence of salmonella enterica serotype paratyphi a as a major cause of enteric fever in kathmandu, nepal. | we performed pulsed-field gel electrophoresis (xbai) on 114 bloodstream isolates of salmonella enterica serotype paratyphi a and s. enterica serotype typhi collected from febrile patients in kathmandu, nepal. of the 56 s. paratyphi a isolates, 51 (91%) were indistinguishable, which suggests the emergence of a single clone. in contrast, only 21 (36%) of the 58 s. typhi isolates exhibited a common genotype, which is consistent with endemic disease from multiple sources. | 2006 | 16714040 |
| evolution of the virulence plasmids of non-typhoid salmonella and its association with antimicrobial resistance. | among more than 2,500 serovars, eight contain a virulence plasmid, including medically important salmonella enterica serovars choleraesuis, dublin, enteritidis, and typhimurium. these serovar-specific virulence plasmids vary in size, but all contain the spv operon, which plays a role in the expression of the virulence. genetically, these virulence plasmids are likely derived from a common ancestral plasmid possessing virulence-related genes and loci. based on the analysis of the available dna se ... | 2006 | 16713725 |
| the genetics of salmonella genomic island 1. | multidrug-resistant salmonella enterica serovar typhimurium phage type dt104, resistant to ampicillin, chloramphenicol/florfenicol, streptomycin, sulfonamides, and tetracycline, has disseminated worldwide. the resistance genes reside on the 43-kb salmonella genomic island 1 (sgi1), which is transferable. drug-resistant variants of sgi1 have been identified in numerous serotypes. strains harboring sgi1 may be more virulent and have a tendency to rapidly disseminate. | 2006 | 16713724 |
| induction of the sos response by bacteriophage lytic development in salmonella enterica. | infection of salmonella enterica with lytic mutants of either p22 or se1 bacteriophages triggers the expression of its dna damage-inducible sos response through a lexa-dependent pathway. this induction of the sos system strictly requires the presence of the bacteriophage kil gene. accordingly, plasmid overexpression of the kil gene also promotes the s. enterica sos network induction. furthermore, s. enterica gifsy prophages are induced following the infection with se1 and p22 lytic derivatives. ... | 2006 | 16713610 |
| xanthosine utilization in salmonella enterica serovar typhimurium is recovered by a single aspartate-to-glycine substitution in xanthosine phosphorylase. | xapabr from salmonella enterica was analyzed and compared with the corresponding escherichia coli genes. xapb and xapr, but not xapa, encode functional proteins. an s. enterica xapa(asp72gly) mutant that restores the phosphorolytic activity was selected. the purified mutant enzyme has different kinetic constants than the e. coli enzyme but similar substrate specificity. | 2006 | 16707709 |
| identification of methylation sites in thermotoga maritima chemotaxis receptors. | adaptation in bacterial chemotaxis involves reversible methylation of specific glutamate residues within the cytoplasmic domains of methyl-accepting chemotaxis proteins. the specific sites of methylation in salmonella enterica and escherichia coli chemoreceptors, identified 2 decades ago, established a consensus sequence for methylation by methyltransferase cher. here we report the in vitro methylation of chemoreceptors from thermotoga maritima, a hyperthermophile that has served as a useful sou ... | 2006 | 16707700 |
| crl activates transcription initiation of rpos-regulated genes involved in the multicellular behavior of salmonella enterica serovar typhimurium. | in salmonella enterica serovar typhimurium, the stationary-phase sigma factor sigma(s) (rpos) is required for virulence, stress resistance, biofilm formation, and development of the rdar morphotype. this morphotype is a multicellular behavior characterized by expression of the adhesive extracellular matrix components cellulose and curli fimbriae. the crl protein of escherichia coli interacts with sigma(s) and activates expression of sigma(s)-regulated genes, such as the csgbac operon encoding th ... | 2006 | 16707690 |
| chloroquinolines block antibiotic efflux pumps in antibiotic-resistant enterobacter aerogenes isolates. | efflux mechanisms protect bacterial cells by pumping out toxic compounds and actively contribute to bacterial multidrug resistance. agents inhibiting efflux pumps are of interest for the control of multidrug-resistant bacterial infections. herein we report the effects of new chloroquinoline derivatives that render resistant enterobacter aerogenes isolates noticeably more susceptible to structurally unrelated antibiotics. in addition, some of these chloroquinolines increase the intracellular conc ... | 2006 | 16707249 |
| interpreting streptomycin susceptibility test results for salmonella enterica serovar typhimurium. | resistance or susceptibility of salmonella enterica to streptomycin is widely used as an epidemiological marker. however, there is no clear consensus on the interpretation of streptomycin susceptibility test results. comparison of results obtained with the clinical and laboratory standards institute (clsi) disk diffusion method, the minimum inhibitory concentration (mic) determined by etest and streptomycin resistance genotype for 90 isolates of s. enterica serovar typhimurium suggests that appr ... | 2006 | 16704923 |
| aquariums as reservoirs for multidrug-resistant salmonella paratyphi b. | multidrug-resistant salmonella enterica serovar paratyphi b dt+ isolates from patients with gastroenteritis were identical with isolates from their home aquariums. matched isolates had identical phage types, xbai and is200 profiles, and salmonella genomic island 1 (sgi1). ornamental fish tanks are reservoirs for sgi1-containing s. paratyphi b dt+. | 2006 | 16704796 |
| molecular analysis of fluoroquinolone-resistant salmonella paratyphi a isolate, india. | salmonella enterica serovar paratyphi a is increasingly a cause of enteric fever. sequence analysis of an indian isolate showed a unique strain with high-level resistance to ciprofloxacin associated with double mutations in the dna gyrase subunit gyra (ser83-->phe and asp87-->gly) and a mutation in topoisomerase iv subunit parc (ser80-->arg). | 2006 | 16704790 |
| web-based surveillance and global salmonella distribution, 2000-2002. | salmonellae are a common cause of foodborne disease worldwide. the world health organization (who) supports international foodborne disease surveillance through who global salm-surv and other activities. who global salm-surv members annually report the 15 most frequently isolated salmonella serotypes to a web-based country databank. we describe the global distribution of reported salmonella serotypes from human and nonhuman sources from 2000 to 2002. among human isolates, s. enteritidis was the ... | 2006 | 16704773 |
| comparative genomics reveals what makes an enterobacterial plant pathogen. | the bacterial family enterobacteriaceae contains some of the most devastating human and animal pathogens, including escherichia coli, salmonella enterica and species of yersinia and shigella. these are among the best-studied of any organisms, yet there is much to be learned about the nature and evolution of interactions with their hosts and with the wider environment. comparative and functional genomics have fundamentally improved our understanding of their modes of adaptation to different ecolo ... | 2006 | 16704357 |
| fitness of human enteric pathogens on plants and implications for food safety. | the continuous rise in the number of outbreaks of foodborne illness linked to fresh fruit and vegetables challenges the notion that enteric pathogens are defined mostly by their ability to colonize the intestinal habitat. this review describes the epidemiology of produce-associated outbreaks of foodborne disease and presents recently acquired knowledge about the behavior of enteric pathogens on plants, with an emphasis on salmonella enterica, escherichia coli o157:h7, and listeria monocytogenes. ... | 2006 | 16704355 |
| nationwide outbreak of salmonella enterica serotype agona infections in infants in france, linked to infant milk formula, investigations ongoing. | 2005 | 16702636 | |
| prevalence of shiga toxin-producing escherichia coli and salmonella enterica in rock pigeons captured in fort collins, colorado. | the potential role of rock pigeons (columba livia) in the epidemiology of shiga toxin-producing escherichia coli (stec) and salmonella enterica is unclear. our objective was to determine the prevalence of stec and s. enterica in pigeons at urban and dairy settings as a function of season. prevalence of stec and s. enterica was estimated by bacteriologic culture of cloacal swabs collected from pigeons trapped at urban and dairy locations in and around fort collins, colorado from january to novemb ... | 2006 | 16699148 |
| differences in gene expression levels and in enzymatic qualities account for the uneven contribution of superoxide dismutases sodci and sodcii to pathogenicity in salmonella enterica. | most salmonella enterica serovars produce two periplasmic [cu,zn] superoxide dismutases, sodci, which is prophage encoded, and sodcii, encoded by a conserved chromosomal gene. both enzymes were proposed to enhance salmonella virulence by protecting bacteria against products of macrophage oxidative burst. however, we previously found sodci, but not sodcii, to play a role during mouse infection by s. enterica serovar typhimurium. here we have extended these findings to another serovar of epidemiol ... | 2006 | 16697686 |
| antagonistic activity of probiotic lactobacilli and bifidobacteria against entero- and uropathogens. | to develop in vitro assays for comparing the antagonistic properties and anti-oxidative activity of probiotic lactobacillus and bifidobacterium strains against various entero- and urinary pathogens. | 2006 | 16696680 |
| lawsonia intracellularis infection in the large intestines of pigs. | in this study we examined the proliferative enteropathy, caused by the obligate intracellular bacterium lawsonia intracellularis, in colon of naturally infected pigs, using immunohistochemistry, in situ hybridisation and scanning confocal laser microscopy. when 396 pigs submitted for routine laboratory examination were investigated, large intestinal gross lesions were seen in 93, including 74 cases of l. intracellularis colitis (proliferative enteropathy). fifty-one pigs without recorded colonic ... | 2006 | 16689824 |
| cytotoxin clya from escherichia coli assembles to a 13-meric pore independent of its redox-state. | clya is a pore-forming toxin from virulent escherichia coli and salmonella enterica strains. here, we show that the intrinsic hemolytic activity of clya is independent of its redox state, and that the assembly of both reduced and oxidized clya to the ring-shaped oligomer is triggered by contact with lipid or detergent. a rate-limiting conformational transition in membrane-bound clya monomers precedes their assembly to the functional pore. we obtained a three-dimensional model of the detergent-in ... | 2006 | 16688219 |
| treatment of enteric fever in children on the basis of current trends of antimicrobial susceptibility of salmonella enterica serovar typhi and paratyphi a. | recent reports indicate decreased susceptibility of s. typhi to fluoroquinolones, especially ciprofloxacin. chloramphenicol has been suggested as first line therapy of enteric fever in many studies. this is a prospective study that describes the trends of antimicrobial susceptibility of s. typhi and s. paratyphi a causing bacteraemia in children and reports therapeutic failure to ciprofloxacin and evaluates the possible use of chloramphenicol, ampicillin, ciprofloxacin and third generation cepha ... | 2006 | 16687859 |
| analysis of the salmonella typhimurium proteome through environmental response toward infectious conditions. | salmonella enterica serovar typhimurium (also known as salmonella typhimurium) is a facultative intracellular pathogen that causes approximately 8,000 reported cases of acute gastroenteritis and diarrhea each year in the united states. although many successful physiological, biochemical, and genetic approaches have been taken to determine the key virulence determinants encoded by this organism, the sheer number of uncharacterized reading frames observed within the s. enterica genome suggests tha ... | 2006 | 16684765 |
| evidence that feedback inhibition of nad kinase controls responses to oxidative stress. | formation of nadp+ from nad+ is catalyzed by nad kinase (nadk; ec 2.7.1.23). evidence is presented that nadk is the only nad kinase of salmonella enterica and is essential for growth. nadk is inhibited allosterically by nadph and nadh. without effectors, nadk exists as an equilibrium mixture of dimers and tetramers (kd = 1.0 +/- 0.8 mm) but is converted entirely to tetramers in the presence of the inhibitor nadph. comparison of nadk kinetic parameters with pool sizes of nadh and nadph suggests t ... | 2006 | 16682646 |
| the virulence markers of salmonella enterica serovar typhimurium. different phage-type strains isolated in slovakia. | phage-typing determination of cell-surface hydrophobicity, motility, and serovar-specific virulence plasmid was performed in a collection of 154 clinical isolates of s. enterica serovar typhimurium (set) isolated in slovakia. all isolates were also examined in pcr for the presence of both stn (enterotoxin) and irob (siderophore) genes. the dt104 was the definitive phage type most frequently identified (37.7 %), the second most frequently isolated phage type was dt41 (5.8 %); the occurrence of ot ... | 2005 | 16681151 |
| occurrence of swine salmonellosis in postweaning multisystemic wasting syndrome (pmws) affected pigs concurrently infected with porcine reproduction and respiratory syndrome virus (prrsv). | fourteen diseased pigs from four farms in which there had been an outbreak of salmonellosis were investigated. granulomatous inflammation with depletion of lymphocytes was observed in the swollen lymph nodes in these pigs. antigens to porcine circovirus type 2 (pcv2) were immunolabeled in the lesions along with detection of viral dna as pcv2 by polymerase chain reaction (pcr). in addition, antigens to porcine reproductive respiratory syndrome virus (prrsv) were immunodetected in the lungs and sa ... | 2006 | 16679733 |
| rapid and simple detection of food poisoning bacteria by bead assay with a microfluidic chip-based system. | a rapid bead assay for detecting pathogenic bacteria with a simple microfluidic chip-based system was developed. five oligonucleotide probes corresponding to the 16s rrna of the targeted bacteria were coupled covalently to fluorescent beads. four species of bacteria (escherichia coli, salmonella enterica subsp. enterica serovar enteritidis, yersinia enterocolitica, and bacillus cereus) were used as representative food-borne pathogenic bacteria. the rnas extracted from pure cultures of these micr ... | 2006 | 16678290 |
| evaluation of the association between feeding raw meat and salmonella enterica infections at a greyhound breeding facility. | to investigate salmonella enterica infections at a greyhound breeding facility. | 2006 | 16677120 |
| empyema thoracic from salmonella choleraesuis. | 2005 | 16673520 | |
| studies of the coba-type atp:co(i)rrinoid adenosyltransferase enzyme of methanosarcina mazei strain go1. | although methanogenic archaea use b(12) extensively as a methyl carrier for methanogenesis, little is known about b(12) metabolism in these prokaryotes or any other archaea. to improve our understanding of how b(12) metabolism differs between bacteria and archaea, the gene encoding the atp:co(i)rrinoid adenosyltransferase in methanosarcina mazei strain gö1 (open reading frame mm3138, referred to as coba(mm) here) was cloned and used to restore coenzyme b(12) synthesis in a salmonella enterica st ... | 2006 | 16672609 |
| direct visualization of red fluorescent lipoproteins indicates conservation of the membrane sorting rules in the family enterobacteriaceae. | chimeras created by fusing the monomeric red fluorescent protein (rfp) to a bacterial lipoprotein signal peptide (liporfps) were visualized in the cell envelope by epifluorescence microscopy. plasmolysis of the bacteria separated the inner and outer membranes, allowing the specific subcellular localization of liporfps to be determined in situ. when equipped with the canonical inner membrane lipoprotein retention signal cdsr, liporfp was located in the inner membrane in escherichia coli, whereas ... | 2006 | 16672606 |
| increased persistence in escherichia coli caused by controlled expression of toxins or other unrelated proteins. | bacterial populations contain persisters, cells which survive exposure to bactericidal antibiotics and other lethal factors. persisters do not have a genetic resistance mechanism, and their means to tolerate killing remain unknown. in exponentially growing populations of escherichia coli the frequency of persister formation usually is 10(-7) to 10(-5). it has been shown that cells overexpressing either of the toxic proteins hipa and rele, both members of the bacterial toxin-antitoxin (ta) module ... | 2006 | 16672603 |
| salmonella serovars in the herpetofauna of indiana county, pennsylvania. | herpetofaunal salmonella enterica serovars have not been fully examined in any u.s. region. thirty-three salmonella serovars were isolated from 156 samples from 34 species, all within indiana county, pennsylvania. results suggest that herpetofaunas could potentially pose a threat to humans. further understanding of salmonella in herpetofaunas may prevent future human cases. | 2006 | 16672533 |
| survival characteristics of salmonella enterica serovar enteritidis in chicken egg albumen. | salmonella enterica serovar enteritidis (se) is a major foodborne pathogen primarily causing human infection through contaminated chicken eggs. to understand how se survives in chicken egg albumen, we systematically and quantitatively analysed the survival properties of se in egg albumen and identified factors affecting its survival. survival assays of se in egg indicate that egg albumen restricted the growth of se. a major factor that controlled se's growth in egg albumen was iron restriction, ... | 2006 | 16650332 |
| salmonella enterica serovar enteritidis colonization of the chicken caecum requires the hila regulatory protein. | invasion of salmonella into intestinal epithelial cells is believed to be essential for the pathogenesis of salmonella infections. invasion is mediated by genes located on the salmonella pathogenicity island i (spi-1), which are needed for assembling a type three secretion system, that mediates injection of bacterial proteins into the cytosol of epithelial cells, resulting in cytoskeletal rearrangements and as a consequence invasion. hila is the key regulator of the salmonella pathogenicity isla ... | 2006 | 16647227 |
| immunity induced with a salmonella enterica serovar enteritidis live vaccine is regulated by th1-cell-dependent cellular and humoral effector mechanisms in susceptible balb/c mice. | the objective of this study was to characterize the immune response induced by a live attenuated salmonella enteritidis (se; ade(-)/his(-)) vaccine using an intraperitoneal immunization/challenge model in susceptible wild-type and cytokine-deficient balb/c mice. in wild-type mice, inoculation of the se live vaccine induced a protective immune response characterized by both cellular (production of interleukin(il)-12 and interferon(ifn)-gamma, granuloma formation in liver and spleen, dth response) ... | 2006 | 16647169 |
| substrate specificity of bacterial oligosaccharyltransferase suggests a common transfer mechanism for the bacterial and eukaryotic systems. | the pglb oligosaccharyltransferase (otase) of campylobacter jejuni can be functionally expressed in escherichia coli, and its relaxed oligosaccharide substrate specificity allows the transfer of different glycans from the lipid carrier undecaprenyl pyrophosphate to an acceptor protein. to investigate the substrate specificity of pglb, we tested the transfer of a set of lipid-linked polysaccharides in e. coli and salmonella enterica serovar typhimurium. a hexose linked to the c-6 of the monosacch ... | 2006 | 16641107 |
| characterization of antimicrobial resistance of salmonella newport isolated from animals, the environment, and animal food products in canada. | multi-drug-resistant (mdr) salmonella enterica serovar newport strains are increasingly isolated from animals and food products of animal origin and have caused septicemic illness in animals and humans. the purpose of this study was to determine the occurrence and the epidemiologic, phenotypic, and genotypic characteristics of s. newport of animal origin that may infect humans, either via the food chain or directly. during the 1993-2002 period, the office international des epizooties reference l ... | 2006 | 16639942 |
| intracellular salmonella enterica redirect exocytic transport processes in a salmonella pathogenicity island 2-dependent manner. | during intracellular life, salmonella enterica proliferate within a specialized membrane compartment, the salmonella-containing vacuole (scv), and interfere with the microtubule cytoskeleton and cellular transport. to characterize the interaction of intracellular salmonella with host cell transport processes, we utilized various model systems to follow microtubule-dependent transport. the vesicular stomatitis virus glycoprotein (vsvg) is a commonly used marker to follow protein transport from th ... | 2006 | 16637890 |
| reducing the fitness cost of antibiotic resistance by amplification of initiator trna genes. | deformylase inhibitors belong to a novel antibiotic class that targets peptide deformylase, a bacterial enzyme that removes the formyl group from n-terminal methionine in nascent polypeptides. using the bacterium salmonella enterica, we isolated mutants with resistance toward the peptide deformylase inhibitor actinonin. resistance mutations were identified in two genes that are required for the formylation of methionyl (met) initiator trna (trnai)(fmet): the fmt gene encoding the enzyme methiony ... | 2006 | 16636273 |
| differential recognition of citrate and a metal-citrate complex by the bacterial chemoreceptor tcp. | the chemoreceptor tcp of salmonella enterica serovar typhimurium can sense citrate and a metal-citrate complex as distinct attractants. in this study, we tried to investigate the molecular mechanism of this discrimination. that citrate binds directly to tcp was verified by the site-specific thiol modification assays using membrane fractions prepared from escherichia coli cells expressing the mutant tcp receptors in which single cys residues were introduced at positions in the putative ligand-bin ... | 2006 | 16636062 |
| purification and initial biochemical characterization of atp:cob(i)alamin adenosyltransferase (eutt) enzyme of salmonella enterica. | atp:cob(i)alamin adenosyltransferase (eutt) of salmonella enterica was overproduced and enriched to approximately 70% homogeneity, and its basic kinetic parameters were determined. abundant amounts of eutt protein were produced, but all of it remained insoluble. soluble active eutt protein (approximately 70% homogeneous) was obtained after treatment with detergent. under conditions in which cobalamin (cbl) was saturating, km(atp) = 10 microm, kcat = 0.03 s(-1), and vmax = 54.5 nm min(-1). simila ... | 2006 | 16636051 |
| quantitative and simultaneous detection of four foodborne bacterial pathogens with a multi-channel spr sensor. | we report the quantitative and simultaneous detection of four species of bacteria, escherichia coli o157:h7, salmonella choleraesuis serotype typhimurium, listeria monocytogenes, and campylobacter jejuni, using an eight-channel surface plasmon resonance (spr) sensor based on wavelength division multiplexing. detection curves showing spr response versus analyte concentration were established for each species of bacteria in buffer at ph 7.4, apple juice at native ph 3.7, and apple juice at an adju ... | 2006 | 16635568 |
| lipid-specific membrane activity of human beta-defensin-3. | defensins represent a major component of innate host defense against bacteria, fungi, and enveloped viruses. one potent defensin found, e.g., in epithelia, is the polycationic human beta-defensin-3 (hbd3). we investigated the role of the lipid matrix composition, and in particular the presence of negatively charged lipopolysaccharides (lps) from sensitive (escherichia coli, salmonella enterica serovar minnesota) or resistant (proteus mirabilis) gram-negative bacteria or of the zwitterionic phosp ... | 2006 | 16634647 |
| cmy-2 beta-lactamase-producing salmonella enterica serovar infantis isolated from poultry in japan. | 2006 | 16632924 | |
| a severe salmonella enterica serotype paratyphi b infection in a child related to a pet turtle, trachemys scripta elegans. | our report highlights a case of severe childhood salmonellosis related to a pet turtle, a red-eared slider (trachemys scripta elegans). a 6-year-old girl had gastroenteritis complicated with sepsis caused by serotype paratyphi b, which shared the same pulsed-field gel electrophoresis profiles with the organism isolated from a pet turtle. based on our literature survey on childhood invasive salmonellosis acquired from reptiles, this case is the first documented reptile-associated salmonellosis in ... | 2006 | 16632917 |
| effect of environmental stresses on antibody-based detection of escherichia coli o157:h7, salmonella enterica serotype enteritidis and listeria monocytogenes. | to study the reaction patterns of selected antibodies to escherichia coli o157:h7, salmonella enterica serotype enteritidis and listeria monocytogenes cells exposed to various environmental stresses. | 2006 | 16630002 |
| colonization of barley (hordeum vulgare) with salmonella enterica and listeria spp. | colonization of barley plants by the food-borne pathogens salmonella enterica serovar typhimurium and three listeria spp. (l. monocytogenes, l. ivanovii, l. innocua) was investigated in a monoxenic system. herbaspirillum sp. n3 was used as a positive control and escherichia coli hb101 as a negative control for endophytic root colonization. colonization of the plants was tested 1-4 weeks after inoculation by determination of cfu, specific pcr assays and fluorescence in situ hybridization (fish) w ... | 2006 | 16629755 |
| hierarchical involvement of various ggdef domain proteins in rdar morphotype development of salmonella enterica serovar typhimurium. | ggdef and eal domain proteins are involved in the turnover of the novel secondary messenger cyclic-di(3'-->5')-guanylic acid (c-di-gmp) in many bacteria. in this work the role of the 12 ggdef domain proteins encoded by the salmonella enterica serovar typhimurium (s. typhimurium) chromosome in rdar morphotype development was investigated. previously, it was shown that the ggdef domain protein adra activated the biosynthesis of cellulose by production of c-di-gmp. enhancement of the c-di-gmp level ... | 2006 | 16629664 |
| salmonellosis with liver abscess mimicking hepatocellular carcinoma in a diabetic and cirrhotic patient: a case report and review of the literature. | salmonellosis with liver abscess in a cirrhotic liver is extremely rare. we report the first case of salmonellosis with septic shock and liver abscess in a diabetic and cirrhotic patient. the image studies of liver initially favored hepatocellular carcinoma. but no definite focus of sepsis was found. after close follow-up of the liver space-occupied lesion, ultrasound examination revealed the features of liver abscesses at space-occupied lesion later. ultrasound-guided liver aspiration proved ab ... | 2006 | 16629655 |
| salmonella enterica in superficial cervical (prescapular) and ileocecal lymph nodes of slaughtered pigs. | because certain lymph nodes may be incorporated in food products, the presence of salmonella enterica in these tissues could pose a food safety risk. we designed this two-part study to assess the prevalence of salmonella in prescapular lymph nodes from normal slaughtered swine. prescapular lymph nodes were collected from 300 systematically selected pigs in study 1 and, in study 2, from 75 pigs distributed among 10 herds. for study 2, pooled bacterial cultures were also completed on ileocecal lym ... | 2006 | 16629040 |
| inhibition of salmonella enterica and escherichia coli o157:h7 on roasted turkey by edible whey protein coatings incorporating the lactoperoxidase system. | the effects of whey protein isolate (wpi) coatings incorporating a lactoperoxidase system (lpos) on the inhibition of salmonella enterica and escherichia coli o157:h7 on roasted turkey were studied by testing the initial inhibition as well as the inhibition during storage. the initial antimicrobial effects of wpi coatings incorporating lpos (lpos-wpi coatings) were examined with various inoculation levels and lpos concentrations. lpos-wpi coatings with 7 and 4% of lpos demonstrated initial 3- an ... | 2006 | 16629020 |
| comparison of antibiotic susceptibility profiles and molecular typing patterns of clinical and environmental salmonella enterica serotype newport. | the genus salmonella is composed of more than 2,400 serotypes, many of which cause enteric diseases in humans and animals. several salmonella serotypes are multidrug resistant, and there is evidence of the clonal spread of these strains from animals to humans. salmonella enterica serotype newport is one of the serotypes that increasingly present a multidrug-resistant phenotype. source tracking and antibiotic resistance testing are important considerations for identifying the outbreak strain. the ... | 2006 | 16629015 |
| comparison of prevalence, antimicrobial resistance, and occurrence of multidrug-resistant salmonella in antimicrobial-free and conventional pig production. | conventional swine production evolved to routinely use antimicrobials, and common occurrence of antimicrobial-resistant salmonella has been reported. there is a paucity of information on the antimicrobial resistance of salmonella in swine production in the absence of antimicrobial selective pressure. therefore, we compared the prevalence and antimicrobial resistance of salmonella isolated from antimicrobial-free and conventional production systems. a total of 889 pigs and 743 carcasses were samp ... | 2006 | 16629014 |
| detection of multiple antibiotic-resistant salmonella enterica serovar typhimurium dt104 by phage replication-competitive enzyme-linked immunosorbent assay. | a phage replication-competitive enzyme-linked immunosorbent assay (pr-celisa) was developed for the detection of multiple antibiotic-resistant salmonella typhimurium dt104. in the pr-celisa procedure, a phage, bp1, was inoculated into a log-phase bacterial culture at a ratio of 1:100. after a 3-h incubation of the mixture, bp1 replication was measured by celisa based on the competitive binding between bp1 and biotinylated bp1 to salmonella typhimurium smooth lipopolysaccharide. among the 84 salm ... | 2006 | 16629013 |
| inhibition of salmonella enterica by plant-associated pseudomonads in vitro and on sprouting alfalfa seed. | foodborne illness due to the consumption of contaminated raw or lightly cooked sprouts is a continuing food safety concern. in this study, we tested several plant-associated pseudomonads for their ability to inhibit the growth of salmonella enterica both in vitro and in situ. an agar spot bioassay method was used with three different media. only pseudomonas fluorescens 2-79 produced clear zones of inhibition when tested against five serovars of s. enterica, and activity was dependent on media ty ... | 2006 | 16629011 |
| growth of salmonella enteritidis phage type 30 in almond hull and shell slurries and survival in drying almond hulls. | traceback investigation of a 2000 to 2001 outbreak of salmonellosis associated with consumption of raw almonds led to isolation of the outbreak strain salmonella enterica serovar enteritidis phage type (pt) 30 on three geographically linked almond farms. interviews with these growers revealed that significant rain fell during the 2000 harvest when many almonds were drying on the ground. the objectives of this study were to document weather conditions during the 2000 harvest, determine the potent ... | 2006 | 16629010 |
| improved cell typing by charge-state deconvolution of matrix-assisted laser desorption/ionization mass spectra. | robust, specific, and rapid identification of toxic strains of bacteria and viruses, to guide the mitigation of their adverse health effects and optimum implementation of other response actions, remains a major analytical challenge. this need has driven the development of methods for classification of microorganisms using mass spectrometry, particularly matrix-assisted laser desorption/ionization mass spectrometry (maldi-ms), that allows high-throughput analyses with minimum sample preparation. ... | 2006 | 16628570 |
| salmonella enterica serovar enteritidis producing a tem-52 beta-lactamase: first report in spain. | tem-52 is an extended-spectrum beta-lactamase (esbl) that is being increasingly reported in enterobacteria. in spain, tem-52 had been reported before only in escherichia coli. here we report the first finding of a tem-52 esbl in salmonella in spain, associated to a tn3 transposon. | 2006 | 16626913 |
| virulence-defective strains of salmonella enterica serovar typhi as candidates for education at level 2 facilities. | the use of biosafety level 3 pathogens is an essential element of education and training at medical schools. we previously reported on invasion-defective strains of salmonella enterica serovar typhi, gtc 3p408 (deltainva, deltasipb) and gtc 3p409 (deltainva, deltasipb, and deltaviab), as candidates for use in educational programs. vi negative strains of s. enterica serovar typhi became extremely sensitive to complement attack but showed increased invasiveness. therefore, this study was conducted ... | 2006 | 16625049 |
| molecular genotyping of salmonella enterica abortusovis by pulsed field gel electrophoresis. | genotyping of salmonella strains is an important tool to discriminate among isolates and to improve epidemiological studies when an outbreak occurs. no phagetyping scheme is available for salmonella enterica subsp. enterica serovar abortusovis (sao) and molecular methods previously used were not standardized and were time consuming. among the dna-based methods of genotyping, pulsed field gel electrophoresis (pfge) is currently in use to subtype salmonella isolates. in this study we evaluated the ... | 2006 | 16624505 |
| the iron efflux protein ferroportin regulates the intracellular growth of salmonella enterica. | we investigated the influence of the macrophage iron exporter ferroportin and its ligand hepcidin on intracellular salmonella growth. elevated ferroportin expression inhibited bacterial multiplication; hepcidin-induced ferroportin down-regulation enhanced it. expression analysis of iron-responsive salmonella genes indicated ferroportin-mediated iron deprivation. these results demonstrate a role for ferroportin in antimicrobial resistance. | 2006 | 16622252 |
| influence of slc11a1 on the outcome of salmonella enterica serovar enteritidis infection in mice is associated with th polarization. | genetic analyses identified ses1 as a significant quantitative trait locus influencing the carrier state of 129s6 mice following a sublethal challenge with salmonella enterica serovar enteritidis. previous studies have determined that slc11a1 was an excellent candidate gene for ses1. kinetics of infection in 129s6 mice and slc11a1-deficient (129s6-slc11a1(tm1mcg)) mice demonstrated that the wild-type allele of slc11a1 contributed to the s. enterica serovar enteritidis carrier state as early as 7 ... | 2006 | 16622216 |
| identification of the sigmae regulon of salmonella enterica serovar typhimurium. | the extracytoplasmic function sigma factor, sigma(e), has been shown to play a critical role in virulence of salmonella enterica serovar typhimurium (s. typhimurium). the previously optimized two-plasmid system has been used to identify s. typhimurium promoters recognized by rna polymerase containing sigma(e). this method allowed identification of 34 sigma(e)-dependent promoters that direct expression of 62 genes in s. typhimurium, 23 of which (including several specific for s. typhimurium) have ... | 2006 | 16622052 |
| functional characterization of the fimh adhesin from salmonella enterica serovar enteritidis. | salmonella enterica serovar enteritidis has emerged during the last 20 years as the major causative agent of food-borne gastroenteritis in humans and as the major infectious agent on poultry farms, replacing salmonella enterica serovar typhimurium as the dominant pathogenic serovar. because adhesion to gut tissues and colonization of the alimentary tract, mediated in large part by the fimh adhesins located on type 1 fimbriae, is an important stage in the pathogenesis of both serovars, the bindin ... | 2006 | 16622051 |
| flagellar glycosylation - a new component of the motility repertoire? | the biosynthesis, assembly and regulation of the flagellar apparatus has been the subject of extensive studies over many decades, with considerable attention devoted to the peritrichous flagella of escherichia coli and salmonella enterica. the characterization of flagellar systems from many other bacterial species has revealed subtle yet distinct differences in composition, regulation and mode of assembly of this important subcellular structure. glycosylation of the major structural protein, the ... | 2006 | 16622043 |
| the rate of adaptive evolution in enteric bacteria. | here we estimate the rate of adaptive substitution in a set of 410 genes that are present in 6 escherichia coli and 6 salmonella enterica genomes. we estimate that more than 50% of amino acid substitutions in this set of genes have been fixed by positive selection between the e. coli and s. enterica lineages. we also show that the proportion of adaptive substitutions is uncorrelated with the rate of amino acid substitution or gene function but that it may be correlated with levels of synonymous ... | 2006 | 16621913 |
| posttranscriptional control of the salmonella enterica flagellar hook protein flge. | previous work suggested that the flge (flagellar hook subunit) protein in salmonella enterica serovar typhimurium was posttranscriptionally regulated in response to the stage of flagellar assembly. specifically, the flge protein could be detected in flagellar mutants defective at the stages of assembly before or after rod assembly but not in rod assembly mutants, yet flge mrna levels were unaffected. to elucidate posttranscriptional mechanisms involved in the coupling of flge gene expression to ... | 2006 | 16621824 |
| characterisation of antimicrobial resistance patterns and class 1 integrons among escherichia coli and salmonella enterica serovar choleraesuis strains isolated from humans and swine in taiwan. | escherichia coli isolates from humans (n=110) and swine (n=61) and salmonella enterica serovar choleraesuis isolates (n=95) from swine in southern taiwan were characterised for antimicrobial resistance patterns and class 1 integrons. all e. coli isolates and s. choleraesuis isolates were multidrug resistant and demonstrated high resistance to beta-lactams, aminoglycosides, tetracycline, sulfonamides, spectinomycin, chloramphenicol and nalidixic acid. by polymerase chain reaction and dna sequenci ... | 2006 | 16621462 |
| studies on the interaction between salmonella enterica ser. typhimurium and intestinal helminths in pigs. | concomitant infections with helminths and bacteria may affect the course and the resulting disease outcome of the individual infections. salmonella, oesophagostomum, trichuris and ascaris coexist naturally in pig herds in denmark, and possible interactions were studied. pigs in one experiment were trickle infected with low or moderate dose levels of oesophagostomum spp. and challenge infected with s. typhimurium. in another experiment, pigs were inoculated with s. typhimurium followed by a chall ... | 2006 | 16621287 |
| immunogenicity of salmonella vector vaccines expressing sbr of streptococcus mutans under the control of a t7-nirb (dual) promoter system. | the purpose of the present study was to determine if a salmonella vector expressing the cloned saliva-binding region (sbr) of streptococcus mutans or sbr linked to the a2 and b subunits of cholera toxin (cta2/b) under the control of both the t7 and nirb promoters (t7-nirb dual promoter) was more effective in inducing mucosal and systemic anti-sbr antibody responses than salmonella clones expressing the same antigens but under the control of either the nirb or t7 promoter. mice were immunized by ... | 2006 | 16621196 |
| common ground for the control of multidrug-resistant salmonella in ground beef. | a strategy to combat multidrug-resistant (mdr) salmonella in ground beef is urgently needed. a national multi-disciplinary meeting reviewed the epidemiology of mdr salmonella infection and contamination in humans, animals, and retail meat. in spite of a recent overall decrease in human mdr salmonella isolates, certain types, such as salmonella enterica serotype newport multidrug-resistant-ampc strain and salmonella enterica serotype typhimurium definitive type (dt) 104, have persisted, and sever ... | 2006 | 16619160 |
| otitis interna (labyrinthitis) associated with salmonella enterica arizonae in turkey poults. | otitis interna was diagnosed in five 9-to-21-day-old turkey poults with clinical signs of paralysis, opisthotonus, torticollis, blindness, and increased mortality. gross and microscopic lesions in the poults included omphalitis, typhlitis, hepatitis, meningoencephalitis, ophthalmitis, neuritis and ganglionitis of the vestibulocochlear nerve, and otitis interna. salmonella enterica arizonae was isolated from the brains, eyes, intestines, yolk sacs, and livers of poults. birds with otitis interna ... | 2006 | 16617998 |
| a salmonella-based, propionate-inducible, expression system for salmonella enterica. | the expression and regulatory properties of a propionate-regulated overexpression system (salmonella enterica prpbcde promoter (p(prpb)) and positive regulator (prpr)) were evaluated in wild-type s. enterica serovar typhimurium tr6583 and prpb(-) or prpd(-) versions of this strain and compared with the arabinose-regulated t7 expression system. the wild-type strain showed low expression in the absence of propionate and high expression in the presence of propionate under all growth conditions. in ... | 2006 | 16616438 |
| an rna sensor for intracellular mg(2+). | most rna molecules require mg(2+) for their structure and enzymatic properties. here we report the first example of an rna serving as sensor for cytoplasmic mg(2+). we establish that expression of the mg(2+) transporter mgta of salmonella enterica serovar typhimurium is controlled by its 5' untranslated region (5'utr). we show that the 5'utr of the mgta gene can adopt different stem-loop structures depending on the mg(2+) levels, which determine whether transcription reads through into the mgta ... | 2006 | 16615891 |
| the acrab-tolc efflux system of salmonella enterica serovar typhimurium plays a role in pathogenesis. | the ability of an isogenic set of mutants of salmonella enterica serovar typhimurium l354 (sl1344) with defined deletions in genes encoding components of tripartite efflux pumps, including acrb, acrd, acrf and tolc, to colonize chickens was determined in competition with l354. in addition, the ability of l354 and each mutant to adhere to, and invade, human embryonic intestine cells and mouse monocyte macrophages was determined in vitro. the tolc and acrb knockout mutants were hyper-susceptible t ... | 2006 | 16611233 |
| a salmonella type iii secretion effector interacts with the mammalian serine/threonine protein kinase pkn1. | essential to salmonellae pathogenesis is an export device called the type iii secretion system (ttss), which mediates the transfer of bacterial effector proteins from the bacterial cell into the host cell cytoplasm. once inside the host cell, these effectors are then capable of altering a variety of host cellular functions in order to promote bacterial survival and colonization. ssph1 is a salmonella enterica serovar typhimurium ttss effector that localizes to the mammalian nucleus and down-modu ... | 2006 | 16611232 |
| manipulating cellular transport and immune responses: dynamic interactions between intracellular salmonella enterica and its host cells. | intracellular survival and replication within eukaryotic host cells is of central importance for the pathogenesis of infections caused by salmonella enterica. intracellular salmonella translocates a set of effector proteins by means of a type iii secretion system (t3ss) encoded by salmonella pathogenicity island 2 (spi2) that manipulates normal host-cell functions. intracellular survival and replication is linked to the function of the spi2-t3ss, but recent observations show that many additional ... | 2006 | 16611223 |
| epidemiology and clinical aspects of enteric fever in israel. | enteric fever decreased in israel in the last 50 years, but its current epidemiology is unknown. in a nationwide study, we evaluated all cases of enteric fever from 1995 to 2003. on hundred thirty-six cases met the case definition. during the period studied, the incidence of enteric fever decreased from 0.42 to 0.23/100,000. a total of 57.4% of the cases were acquired abroad. the incidence of endemic enteric fever was 2.7 times higher in arabs than in jews. in arabs, salmonella typhi was the cau ... | 2006 | 16606981 |
| probing genomic diversity and evolution of escherichia coli o157 by single nucleotide polymorphisms. | infections by shiga toxin-producing escherichia coli o157:h7 (stec o157) are the predominant cause of bloody diarrhea and hemolytic uremic syndrome in the united states. in silico comparison of the two complete stec o157 genomes (sakai and edl933) revealed a strikingly high level of sequence identity in orthologous protein-coding genes, limiting the use of nucleotide sequences to study the evolution and epidemiology of this bacterial pathogen. to systematically examine single nucleotide polymorp ... | 2006 | 16606700 |
| molecular subtyping of salmonella enterica serovar typhi isolates from colombia and argentina. | salmonella typhi is the etiological agent of typhoid fever with 16 million annual cases estimated worldwide. in colombia and argentina it is a notifiable disease but many cases have only a clinical diagnosis. molecular subtyping of s. typhi is necessary to complement epidemiologic analysis of typhoid fever. the aims of this study were to determine the genetic relationships between the strains circulating in both countries and to evaluate possible variations in the distribution of 12 virulence ge ... | 2006 | 16602990 |
| genomic diversity within phage types of salmonella enterica ssp. enterica serotypes enteritidis and typhimurium. | the diversity among 1354 strains of salmonella enterica subsp. enterica, serotype enteritidis (n = 847) and typhimurium (n = 507) isolated in finland in 1991-2002 (n = 608) and in 2003 (n = 746) were studied. the former strains were studied retrospectively by phage typing and pulsed-field gel electrophoresis (pfge) harmonized in the european salm-gene project. the latter strains were studied prospectively, and the results correlated to their antimicrobial susceptibility and association with trav ... | 2006 | 16602985 |
| pulsenet usa: a five-year update. | pulsenet usa is the molecular surveillance network for foodborne infections in the united states. since its inception in 1996, it has been instrumental in detection, investigation and control of numerous outbreaks caused by shiga toxin-producing escherichia coli o157:[h7] (stec o157), salmonella enterica, listeria monocytogenes, shigella spp., and campylobacter. this paper describes the current status of the network, including the methodologies used and its future possibilities. the currently pr ... | 2006 | 16602975 |
| evaluation of a novel vi conjugate vaccine in a murine model of salmonellosis. | immunisation of balb/c mice with a vaccine containing vi polysaccharide conjugated to the klebsiella pneumoniae outer membrane 40 kda protein (rp40), in combination with escherichia coli heat-labile toxin adjuvant (lt), elicited anti-vi igg antibodies after administration using different routes. testing of the immune serum in opsonisation assays demonstrated the specific enhancement of vi-positive bacterial uptake by cultured murine bone marrow derived macrophages. intra-peritoneal challenge of ... | 2006 | 16600446 |
| antimicrobial susceptibility and characterization of salmonella isolates from processed bison carcasses. | seventeen salmonella enterica serovar hadar isolates recovered from bison were found to possess a range of virulence genes and resistance to tetracycline, gentamicin, sulfamethoxazole, and streptomycin simultaneously. a 1-kb class 1 integron containing the aada1 gene was identified in all isolates. pulsed-field gel electrophoresis found that all isolates were closely related, indicating the possibility of cross-contamination during processing. | 2006 | 16598016 |
| identification of salmonella enterica serovar typhimurium genes important for survival in the swine gastric environment. | since the stomach is a first line of defense for the host against ingested microorganisms, an ex vivo swine stomach contents (ssc) assay was developed to search for genes important for salmonella enterica serovar typhimurium survival in the hostile gastric environment. initial characterization of the ssc assay (ph 3.87) using previously identified, acid-sensitive serovar typhimurium mutants revealed a 10-fold decrease in survival for a phop mutant following 20 min of challenge and no survival fo ... | 2006 | 16597989 |
| analyses of the red-dry-rough phenotype of an escherichia coli o157:h7 strain and its role in biofilm formation and resistance to antibacterial agents. | in a previous study, we identified congo red-binding and -nonbinding phase variants of escherichia coli serotype o157:h7 strain atcc 43895. the congo red-binding variant, strain 43895or, produced a dry, aggregative colony that was similar to the red, dry, and rough (rdar) phenotype characteristic of certain strains of salmonella. in contrast, variant 43895ow produced a smooth and white colony morphology. in this study, we show that, similar to rdar strains of salmonella enterica serovar typhimur ... | 2006 | 16597958 |
| differentiation of escherichia coli pathotypes by oligonucleotide spotted array. | to accurately determine the pathotypes of escherichia coli strains, a comprehensive assessment of each strain that targets multiple genes is required. a new approach to the identification and characterization of e. coli pathotypes was developed by constructing gene-specific probes (70-mers) for not only the virulence genes associated with each e. coli pathotype but also the o157-, cft073-, and k-12-specific and common genes of each pathotype. analysis of oligonucleotide probes with reference and ... | 2006 | 16597882 |
| salmonella enterica serovar paratyphi a and s. enterica serovar typhi cause indistinguishable clinical syndromes in kathmandu, nepal. | enteric fever is a major global problem. emergence of antibacterial resistance threatens to render current treatments ineffective. there is little research or public health effort directed toward salmonella enterica serovar paratyphi a, because it is assumed to cause less severe enteric fever than does s. enterica serovar typhi. there are few data on which to base this assumption, little is known of the serovar's antibacterial susceptibilities, and there is no readily available tolerable vaccina ... | 2006 | 16586383 |
| an allele of gyra prevents salmonella enterica serovar typhimurium from using succinate as a carbon source. | a mutant gyra allele resulting in an a271e substitution in the dna gyrase protein generated a strain unable to grow on the c(4)-dicarboxylates succinate, malate, and fumarate. bacteria harboring gyra751 displayed decreased negative supercoiling in cells. expression of the dcta gene, which encodes the c(4)-dicarboxylate transporter, was reduced in a gyra751 mutant, providing the first evidence that dcta expression is supercoiling sensitive and uncovering a simple metabolic screen for lesions in g ... | 2006 | 16585773 |
| mechanism of hila repression by 1,2-propanediol consists of two distinct pathways, one dependent on and the other independent of catabolic production of propionate, in salmonella enterica serovar typhimurium. | a glycerol dehydrogenase gene was selected as a multicopy suppressor rescuing the reduced hila expression in the salmonella enterica serovar typhimurium cpxa mutant. a substrate of the enzyme, 1,2-propanediol, repressed hila expression. the 1,2-propanediol-mediated repression at 150 mm, but not that at 300 mm, was abrogated by blocking the catabolism producing propionate from 1,2-propanediol. | 2006 | 16585772 |
| structural alterations of the cysteine desulfurase iscs of salmonella enterica serovar typhimurium reveal substrate specificity of iscs in trna thiolation. | the cysteine desulfurase iscs in salmonella enterica serovar typhimurium is required for the formation of all four thiolated nucleosides in trna, which is thought to occur via two principally different biosynthetic pathways. the synthesis of 4-thiouridine (s(4)u) and 5-methylaminomethyl-2-thiouridine (mnm(5)s(2)u) occurs by a transfer of sulfur from iscs via various proteins to the target nucleoside in the trna, and no iron-sulfur cluster protein participates, whereas the synthesis of 2-thiocyti ... | 2006 | 16585765 |
| conserving a volatile metabolite: a role for carboxysome-like organelles in salmonella enterica. | salmonellae can use ethanolamine (ea) as a sole source of carbon and nitrogen. this ability is encoded by an operon (eut) containing 17 genes, only 6 of which are required under standard conditions (37 degrees c; ph 7.0). five of the extra genes (eutm, -n, -l, -k, and -g) become necessary under conditions that favor loss of the volatile intermediate, acetaldehyde, which escapes as a gas during growth on ea and is lost at a higher rate from these mutants. the eutm, -n, -l, and -k genes encode hom ... | 2006 | 16585748 |
| invasive multidrug-resistant non-typhoidal salmonella infections in africa: zoonotic or anthroponotic transmission? | in africa, multidrug-resistant non-typhoidal salmonellae (nts) are one of the leading causes of morbidity and high mortality in children under 5 years of age, second in importance only to pneumococcal disease. the authors studied nts isolates from paediatric admissions at two hospitals in nairobi, kenya, and followed the index cases to their homes, where rectal swabs and stools from parents and siblings, and from animals in close contact, were obtained. the majority of nts obtained from cases we ... | 2006 | 16585646 |
| human vitamin b12 absorption measurement by accelerator mass spectrometry using specifically labeled (14)c-cobalamin. | there is a need for an improved test of human ability to assimilate dietary vitamin b(12). assaying and understanding absorption and uptake of b(12) is important because defects can lead to hematological and neurological complications. accelerator mass spectrometry is uniquely suited for assessing absorption and kinetics of carbon-14 ((14)c)-labeled substances after oral ingestion because it is more sensitive than decay counting and can measure levels of (14)c in microliter volumes of biological ... | 2006 | 16585531 |
| attenuated aroa salmonella enterica serovar typhimurium does not induce inflammatory response and early protection of gnotobiotic pigs against parental virulent lt2 strain. | cytokine and inflammatory response against virulent lt2 strain and its attenuated aroa deletion mutant of salmonella enterica serovar typhimurium were compared in gnotobiotic pigs. contrary to the parental strain, the auxotrofic mutant did not induce il-1beta, il-18, tnf-alpha, and ifn-gamma in the ileum and plasma 24h after the infection, did not cause pathological changes in ileal epithelium and mesenteric lymph nodes or immunoreactivity of gp91 phox and peroxynitrite and was not immunostained ... | 2006 | 16584815 |
| variability in antimicrobial resistance among salmonella enterica strains from fattening pigs and sows. | the aim of this study was to determine the prevalence of antibiotic resistance and different resistance patterns for salmonella isolates collected from belgian sows and fattening pigs at different ages and at slaughter. the most frequently isolated serotypes were s. typhimurium (42.3%), s. derby (25.1%), s. goldcoast (7.3%), and s. infantis (4.8%). all 901 isolates were submitted to antimicrobial susceptibility testing for 14 compounds using the disc agar diffusion test. the highest percentage o ... | 2006 | 16584313 |
| the cytokine balance in the maintenance of a persistent infection with salmonella enterica serovar typhimurium in mice. | clpxp, serine protease-disrupted mutant of salmonella enterica serovar typhimurium chi3306 exhibits attenuated but persistent infection in mice. during infection with s. enterica serovar typhimurium clpxp-disrupted mutant, gamma interferon (ifn-gamma) produced by cd4+ cells was up-regulated on day 10 and tumor necrosis factor-alpha (tnf-alpha) produced by cd8+ cells was up-regulated on day 30 after infection. treatment of monoclonal antibodies against cytokines showed that ifn-gamma and interleu ... | 2006 | 16580226 |
| global gene expression of a murein (braun) lipoprotein mutant of salmonella enterica serovar typhimurium by microarray analysis. | braun/murein lipoprotein (lpp) is one of the major outer membrane components of gram-negative enteric bacteria involved in inflammatory responses and septic shock. in previous studies, we reported that two copies of the lipoprotein (lpp) gene (designated as lppa and lppb) existed on the chromosome of salmonella enterica serovar typhimurium. deletion of both lppa and lppb genes rendered salmonella defective in invasion, motility, induction of cytotoxicity, and production of inflammatory cytokines ... | 2006 | 16574345 |
| first report of extended-spectrum-beta-lactamase-producing salmonella enterica isolates in ireland. | 2006 | 16569897 |