| obstructing ileal duplication cyst infected with salmonella in a 2-year-old boy: a case report and review of the literature. | alimentary tract duplications (atds) are rare congenital anomalies, with an incidence of 1 in 4500 individuals. patients with these lesions present in a variety of ways, and although histologically benign, atds can lead to lethal complications including volvulus, intussusception, or bowel obstruction. irrespective of anatomical location, the epithelial lining of atds contains ectopic acid-secreting mucosa in more than 50% of cases, which can lead to ulceration, bleeding, or transmural erosion an ... | 2007 | 17502171 |
| enhanced immunity to plasmodium falciparum circumsporozoite protein (pfcsp) by using salmonella enterica serovar typhi expressing pfcsp and a pfcsp-encoding dna vaccine in a heterologous prime-boost strategy. | two salmonella enterica serovar typhi strains that express and export a truncated version of plasmodium falciparum circumsporozoite surface protein (tcsp) fused to salmonella serovar typhi cytolysin a (clya) were constructed as a first step in the development of a preerythrocytic malaria vaccine. synthetic codon-optimized genes (t-csp1 and t-csp2), containing immunodominant b- and t-cell epitopes present in native p. falciparum circumsporozoite surface protein (pfcsp), were fused in frame to the ... | 2007 | 17502396 |
| inhibition of type iii secretion in salmonella enterica serovar typhimurium by small-molecule inhibitors. | type iii secretion systems (t3ss) are conserved in many pathogenic gram-negative bacteria. small molecules that specifically target t3ss in yersinia and chlamydia spp. have recently been identified. here we show that two such compounds inhibit salmonella t3ss-1, preventing secretion of t3ss-1 effectors, invasion of cultured epithelial cells, and enteritis in vivo. | 2007 | 17502403 |
| resistance to quinolones in salmonella infantis due to overexpression of an active efflux system and a mutation in the gyra gene. | | 2007 | 17504693 |
| a real-time pcr for the detection of salmonella enteritidis in poultry meat and consumption eggs. | a robust duplex 5' nuclease (taqman) real-time pcr was developed and in-house validated for the specific detection of salmonella enterica subspecies enterica serovar enteritidis in whole chicken carcass rinses and consumption eggs. the assay uses specifically designed primers and a taqman probe to target the prot6e gene located on the s. enteritidis specific 60-kb virulence plasmid. as an internal amplification control to monitor salmonella dna in the sample, a second primer/taqman probe set det ... | 2007 | 17512995 |
| physiological and molecular responses of lactuca sativa to colonization by salmonella enterica serovar dublin. | this paper describes the physiological and molecular interactions between the human-pathogenic organism salmonella enterica serovar dublin and the commercially available mini roman lettuce cv. tamburo. the association of s. enterica serovar dublin with lettuce plants was first determined, which indicated the presence of significant populations outside and inside the plants. the latter was evidenced from significant residual concentrations after highly efficient surface disinfection (99.81%) and ... | 2007 | 17513585 |
| risk factors for changing test classification in the danish surveillance program for salmonella in dairy herds. | a surveillance program in which all cattle herds in denmark are classified into salmonella infection categories has been in place since 2002. dairy herds were considered test negative and thus most likely free of infection if salmonella antibody measurements were consistently low in bulk tank milk samples collected every 3 mo. herds were considered test positive and thus most likely infected if the 4-quarter moving average bulk tank milk antibody concentration was high or if there was a large in ... | 2007 | 17517722 |
| [cholangitis with hepatic microabscesses caused by salmonella enterica serovar choleraesuis]. | a 71-year-old man was admitted to the emergency unit of another hospital with a mild gastroenteritis and high fever. on admission g-gt and c-reactive protein (crp) levels were markedly elevated. under nonspecific antibiotic therapy with ampicillin/sulbactam the fever persisted and for the first time, on day 5, the patient complained of right-sided abdominal pain. an increase in the laboratory values indicated cholestasis. after changing the antibiotics to ceftriaxon and metronidazole, acute chol ... | 2007 | 17520506 |
| prophage sequences defining hot spots of genome variation in salmonella enterica serovar typhimurium can be used to discriminate between field isolates. | sixty-one salmonella enterica serovar typhimurium isolates of animal and human origin, matched by phage type, antimicrobial resistance pattern, and place of isolation, were analyzed by microbiological and molecular techniques, including pulsed-field gel electrophoresis (pfge) and plasmid profiling. pfge identified 10 profiles that clustered by phage type and antibiotic resistance pattern with human and animal isolates distributed among different pfge profiles. genomic dna was purified from 23 re ... | 2007 | 17522270 |
| genotypic analysis of salmonella enterica serovar typhi collected during two successive autumnal typhoid outbreaks in southeast tunisia. | investigation of two successive autumnal outbreaks of typhoid fever that occurred in southeast tunisia. | 2007 | 17524573 |
| impact of salmonella typhimurium dt104 virulence factors invc and ssed on the onset, clinical course, colonization patterns and immune response of porcine salmonellosis. | the present study was conducted to study the impact of the virulence factors invc and ssed of the two type iii secretion systems of salmonella enterica serovar typhimurium (s. typhimurium) on the pathogenesis of the porcine s. typhimurium dt104 infection. for this purpose, two s. typhimurium mutant strains with a disrupted invc gene of the salmonella pathogenicity island 1 or with a disrupted ssed gene of the salmonella pathogenicity island 2 have been studied in experimental infection of pigs. ... | 2007 | 17524577 |
| an electrochemical method for simultaneous detection and identification of escherichia coli, staphylococcus aureus and salmonella choleraesuis using a glucose oxidase-peroxidase composite biosensor. | quantification of bacterial pollution by amperometric detection at 0.0 v of glucose consumption at a graphite-teflon-glucose oxidase-peroxidase-ferrocene composite biosensor under flow injection conditions is reported. using escherichia coli as the model bacterium, the composition of the growing medium was optimized. a constant glucose concentration of 4.0 x 10(-4) m was added to the culture medium. the relative response to glucose, expressed as the ratio between the amperometric signal and the ... | 2007 | 17525815 |
| fepa- and tonb-dependent bacteriophage h8: receptor binding and genomic sequence. | h8 is derived from a collection of salmonella enterica serotype enteritidis bacteriophage. its morphology and genomic structure closely resemble those of bacteriophage t5 in the family siphoviridae. h8 infected s. enterica serotypes enteritidis and typhimurium and escherichia coli by initial adsorption to the outer membrane protein fepa. ferric enterobactin inhibited h8 binding to e. coli fepa (50% inhibition concentration, 98 nm), and other ferric catecholate receptors (fiu, cir, and iron) did ... | 2007 | 17526714 |
| differential interaction of aggregatibacter (actinobacillus) actinomycetemcomitans lsrb and rbsb proteins with autoinducer 2. | our previous studies showed that the aggregatibacter actinomycetemcomitans rbsb protein interacts with cognate and heterologous autoinducer 2 (ai-2) signals and suggested that the rbsdabck operon encodes a transporter that may internalize ai-2 (d. james et al., infect. immun. 74:4021-4029, 2006.). however, a. actinomycetemcomitans also possesses genes related to the lsr operon of salmonella enterica serovar typhimurium which function to import ai-2. here, we show that a. actinomycetemcomitans ls ... | 2007 | 17526716 |
| simple approach for isolating mutants expressing fimbriae. | genomes of members of the family enterobacteriaceae contain large repertoires of putative fimbrial operons. since many of these operons are poorly expressed in vitro, a convenient method for inducing elaboration of the encoded fimbriae would greatly facilitate their functional characterization. here we describe a new technique for identifying fimbriated bacteria from a library of transposon mutants by screening with immunomagnetic particles for ligand expression (simple). the simple method was a ... | 2007 | 17526787 |
| bacteriophage therapy to reduce salmonella colonization of broiler chickens. | acute enteric infections caused by salmonellas remain a major public health burden worldwide. poultry, particularly chickens, are known to be the main reservoir for this zoonotic pathogen. although some progress has been made in reducing salmonella colonization of broiler chickens by using biosecurity and antimicrobials, it still remains a considerable problem. the use of host-specific bacteriophages as a biocontrol is one possible intervention by which salmonella colonization could be reduced. ... | 2007 | 17526794 |
| nsrr: a key regulator circumventing salmonella enterica serovar typhimurium oxidative and nitrosative stress in vitro and in ifn-gamma-stimulated j774.2 macrophages. | over the past decade, the flavohaemoglobin hmp has emerged as the most significant nitric oxide (no)-detoxifying protein in many diverse micro-organisms, particularly pathogenic bacteria. its expression in enterobacteria is dramatically increased on exposure to no and other agents of nitrosative stress as a result of transcriptional regulation of hmp gene expression, mediated by (at least) four regulators. one such regulator, nsrr, has recently been shown to be responsible for repression of hmp ... | 2007 | 17526833 |
| differential salmonella survival against communities of intestinal amoebae. | predation from intestinal amoebae may provide selective pressure for the maintenance of high genetic diversity at the salmonella enterica rfb locus, whereby serovars better escape predators in particular environments depending on the o-antigens they express. here, the hypothesis that amoebae from a particular intestinal environment collectively prefer one serovar over another is tested. collections of acanthamoeba, tetramitus, naegleria and hartmannella were isolated from the intestinal tracts o ... | 2007 | 17526835 |
| plasmids derived from gifsy-1/gifsy-2, lambdoid prophages contributing to the virulence of salmonella enterica serovar typhimurium: implications for the evolution of replication initiation proteins of lambdoid phages and enterobacteria. | gifsy-1 and gifsy-2 are lambdoid prophages which contribute to the virulence of salmonella enterica serovar typhimurium. the nucleotide sequence of the replication region of both prophages is identical, and similar in organization to the replication region of bacteriophage lambda. to investigate the replication of the gifsy phages and the relationship between gifsy and host chromosome replication, a plasmid which contained all the genes and regulatory sequences required for autonomous replicatio ... | 2007 | 17526845 |
| role in virulence and protective efficacy in pigs of salmonella enterica serovar typhimurium secreted components identified by signature-tagged mutagenesis. | salmonella enterica serovar typhimurium (s. typhimurium) is a zoonotic enteric pathogen of worldwide importance and pigs are a significant reservoir of human infection. signature-tagged transposon mutagenesis (stm) was used to identify genes required by s. typhimurium to colonize porcine intestines. a library of 1045 signature-tagged mutants of s. typhimurium st4/74 nal(r) was screened following oral inoculation of pigs in duplicate. a total of 119 attenuating mutations were identified in 95 dif ... | 2007 | 17526851 |
| prevalence, distribution and characterisation of ceftiofur resistance in salmonella enterica isolated from animals in the usa from 1999 to 2003. | third-generation cephalosporin (3gc) antimicrobials are the drugs of choice for treatment of salmonellosis in children. salmonella isolated in the usa are assayed by the national antimicrobial resistance monitoring system (narms) for resistance to antimicrobials including first-, second- and third-generation cephalosporins. from 1999 to 2003, 34,411 salmonella were isolated from animals in the usa, of which 10.9% were found to be resistant to ceftiofur, a 3gc used in animals, whilst only 0.3% we ... | 2007 | 17531447 |
| utilization of gaseous ozone for the decontamination of escherichia coli o157:h7 and salmonella on raspberries and strawberries. | each year in the united states, there are approximately 76 million foodborne illnesses, and fresh produce is the second most common vehicle for such illnesses. before going to market, small fruits are not washed or treated in any manner to extend their shelf life. washing alone is not a viable option, and the use of novel technologies should be investigated. one such technology is ozone treatment, which has been used with drinking water since the late 19th century. the efficacy of gaseous ozone ... | 2007 | 17536666 |
| salmonella diagnosis in pig production: methodological problems in monitoring the prevalence in pigs and pork. | salmonellosis is an important foodborne infection in industrialized and developing countries. especially for human salmonellosis caused by salmonella enterica serovar typhimurium, pigs and pork are the major sources of infection. mitigation and control strategies that result from surveillance programs attempt to reduce or even eradicate salmonella in pork to lower consumers' risks. the methodology for salmonella screening in pigs is generally based on antibody detection at slaughter with meat ju ... | 2007 | 17536687 |
| characterization of the inca/c plasmid pcc416 encoding vim-4 and cmy-4 beta-lactamases. | to characterize the antibiotic resistance regions of pcc416, a vim-4- and cmy-4-encoding plasmid from clinical enterobacteria, and to elucidate its relation with the cmy-encoding plasmids widely diffused in salmonella. | 2007 | 17540674 |
| the selection of acceptable protein mutations. | we have determined the general constraints that govern sequence divergence in proteins that retain entirely, or very largely, the same structure and function. to do this we collected data from three different groups of orthologous sequences: those found in humans and mice, in humans and chickens, and in escherichia coli and salmonella enterica. in total, these organisms have 21,738 suitable pairs of orthologs, and these contain nearly 2 million mutations. the three groups differ greatly in the t ... | 2007 | 17540730 |
| a fusogenic peptide expressed on the surface of salmonella enterica elicits ctl responses to a dengue virus epitope. | attenuated salmonella strains are used widely as live carriers of antigens because they elicit both mucosal and systemic immunity against passenger antigens. however, they generally evoke poor cytotoxic t cell (ctl) responses because salmonella resides within vacuolar compartments and the passenger antigens must travel to the cytosol and be processed through the mhc class i-dependent pathway to simulate ctls. to address this problem, we designed a fusion protein to destabilize the phagosome memb ... | 2007 | 17543427 |
| antimicrobial susceptibility phenotypes, resistance determinants and dna fingerprints of salmonella enterica serotype typhimurium isolated from bovine in southern japan. | a longitudinal study was conducted in cattle to determine the antimicrobial resistance phenotypes, integron elements, resistance genes and pulsed-field gel electrophoresis fingerprints among salmonella enterica serotype typhimurium isolates. a total of 33 strains were isolated and categorised into groups a, b and c during the period 1989-2004. thirty-one strains (93.9%) showed resistance to ampicillin (a) encoded by bla(oxa-1), bla(tem) and bla(pse-1) genes; 84.8% showed resistance to chloramphe ... | 2007 | 17543503 |
| neutralizing and cross-reactive antibodies against enterobacterial lipopolysaccharide. | lipopolysaccharide (lps, endotoxin) elicits an immune reaction which is responsible for many of the harmful effects seen in septic shock patients. the eradication of bacteria by antibiotics is insufficient to resolve the pathology due to the lack of lps neutralization. lps-neutralizing antibodies have been described; however, these were specific for the serotype of the infecting bacteria and thus not useful for the treatment of septic shock patients. structural analyses revealed that the lps str ... | 2007 | 17544324 |
| comparison of growth phase on salmonella enterica serovar typhimurium invasion in an epithelial cell line (ipec j2) and mucosal explants from porcine small intestine. | salmonella typhimurium dt104 is a zoonotic enteropathogen of increasing concern for human health. in this study, the influence of growth phase on invasiveness of a s. typhimurium dt104 field isolate and two reference strains (sl1344 and atcc 14028) was compared in ipec j2 cells and mucosal explants from porcine ileum. internalized bacteria were quantified by a gentamicin resistance assay. after 90 min of exposure to the apical aspect of epithelial monolayers or luminal surface of explants, inter ... | 2008 | 17544508 |
| net replication of salmonella enterica serovars typhimurium and choleraesuis in porcine intestinal mucosa and nodes is associated with their differential virulence. | salmonella enterica is a facultative intracellular pathogen of worldwide importance and causes a spectrum of diseases depending on serovar- and host-specific factors. oral infection of pigs with s. enterica serovar typhimurium strain 4/74 produces acute enteritis but is rarely fatal, whereas serovar choleraesuis strain a50 causes systemic disease with a high mortality rate. with a porcine ligated ileal loop model, we observed that systemic virulence of serovar choleraesuis a50 is not associated ... | 2007 | 17548482 |
| salicylidene acylhydrazides that affect type iii protein secretion in salmonella enterica serovar typhimurium. | a collection of nine salicylidene acylhydrazide compounds were tested for their ability to inhibit the activity of virulence-associated type iii secretion systems (t3sss) in salmonella enterica serovar typhimurium. the compounds strongly affected salmonella pathogenicity island 1 (spi1) t3ss-mediated invasion of epithelial cells and in vitro secretion of spi1 invasion-associated effector proteins. the use of a spi1 effector beta-lactamase fusion protein implicated intracellular entrapment of the ... | 2007 | 17548496 |
| regulation of dmbt1 via nod2 and tlr4 in intestinal epithelial cells modulates bacterial recognition and invasion. | mucosal epithelial cell layers are constantly exposed to a complex resident microflora. deleted in malignant brain tumors 1 (dmbt1) belongs to the group of secreted scavenger receptor cysteine-rich proteins and is considered to be involved in host defense by pathogen binding. this report describes the regulation and function of dmbt1 in intestinal epithelial cells, which form the primary immunological barrier for invading pathogens. we report that intestinal epithelial cells up-regulate dmbt1 up ... | 2007 | 17548659 |
| tandem repeat analysis for surveillance of human salmonella typhimurium infections. | in denmark, as part of the national laboratory-based surveillance system of human enteric infections, all salmonella enterica serotype typhimurium isolates are currently subtyped by using phage typing, antimicrobial resistance profiles, and pulsed-field gel electrophoresis (pfge). we evaluated the value of real-time typing that uses multiple-locus variable-number tandem-repeats analysis (mlva) of s. typhimurium to detect possible outbreaks. because only a few subtypes identified by pfge and phag ... | 2007 | 17552091 |
| drug-resistant nontyphoidal salmonella bacteremia, thailand. | | 2007 | 17552113 |
| international spread of multidrug-resistant salmonella schwarzengrund in food products. | we compared 581 salmonella enterica serotype schwarzengrund isolates from persons, food, and food animals in denmark, thailand, and the united states by antimicrobial drug susceptibility and pulsed-field gel electrophoresis (pfge) typing. resistance, including resistance to nalidixic acid, was frequent among isolates from persons and chickens in thailand, persons in the united states, and food imported from thailand to denmark and the united states. a total of 183 pfge patterns were observed, an ... | 2007 | 17553251 |
| inhibition of salmonella enterica serotype enteritidis on agar and raw chicken by carvacrol vapour. | carvacrol is known to inhibit a number of food borne pathogens. the activity of carvacrol vapour was evaluated against s. enterica serotype enteritidis on tryptone soya agar and on pieces of raw chicken. on agar, the size of the inhibition zone increased with decreasing volume of agar, increasing vapour exposure period, increasing temperature, increasing volume of carvacrol used and with decreasing bacterial density. inhibition was equally effective under aerobic and anaerobic conditions. on chi ... | 2007 | 17553584 |
| prevalence of selected enteropathogenic bacteria in hungarian finishing pigs. | the aim of this study was to obtain prevalence estimates about the most important enteropathogenic bacteria: lawsonia intracellularis, brachyspira hyodysenteriae, brachyspira pilosicoli, salmonella enterica and clostridium perfringens a and c in hungarian farrow-to-finish pig herds. a total of 31 herds were selected, from where six pooled faecal samples, each containing three individual rectal faecal samples were collected from fattening pigs of 5-6 months of age. all 186 samples were examined b ... | 2007 | 17555287 |
| identification of a transcriptional regulator that controls intracellular gene expression in salmonella typhi. | salmonella enterica serovar typhi (s. typhi), the aetiological agent of typhoid fever, is an exclusively human pathogen. little is known about specific factors that may confer to this bacterium its unique pathogenic features. one of these determinants is cdtb, a homologue of the active subunit of the cytolethal distending toxin, which causes dna damage leading to cell cycle arrest and distension of intoxicated cells. a unique property of s. typhi cdtb is that it is only synthesized when this bac ... | 2007 | 17555437 |
| clonal reconquest of antibiotic-susceptible salmonella enterica serotype typhi in son la province, vietnam. | in the last three decades, high rates of resistance to common first-line antimicrobial agents have been reported in salmonella enterica serotype typhi (typhi), the causative organism of typhoid fever (tf), in many regions of the world, especially in south east asia. analysis of typhi strains isolated from outbreaks and sporadic cases of tf in son la province, northwest vietnam, in 2002 revealed that 94.5% (85/90) of the isolates were fully susceptible to amoxicillin, chloramphenicol, cotrimoxazo ... | 2007 | 17556632 |
| mutations in the tryptophan operon allow purf-independent thiamine synthesis by altering flux in vivo. | phosphoribosyl amine (pra) is an intermediate in purine biosynthesis and also required for thiamine biosynthesis in salmonella enterica. pra is normally synthesized by phosphoribosyl pyrophosphate amidotransferase, a high-turnover enzyme of the purine biosynthetic pathway encoded by purf. however, purf-independent pra synthesis has been observed in strains having different genetic backgrounds and growing under diverse conditions. genetic analysis has shown that the anthranilate synthase-phosphor ... | 2008 | 17557816 |
| pathogen specific carbohydrate antigen microarrays: a chip for detection of salmonella o-antigen specific antibodies. | a salmonella o-antigen microarray was developed by covalent coupling of oligosaccharide antigens specific for serogroups salmonella enterica sv. paratyphi (group a), typhimurium (group b) and enteritidis (group d). antibodies were correctly detected in sera from patients with culture verified salmonellosis. high serogroup-specificity was seen with the disaccharide antigens. with the larger antigens, containing the backbone sequence manalpha1-2rhaalpha1-2gal (mrg), common backbone-specific antibo ... | 2008 | 17558551 |
| endogenous endophthalmitis due to salmonella choleraesuis in an hiv-positive patient. | to report a case of endogenous endophthalmitis caused by the gram-negative bacterium salmonella choleraesuis as a first sign of hiv infection in a patient from thailand. | 2007 | 17558841 |
| [a rare outbreak of food poisoning caused by salmonella enterica serovar. oranienburg--a case report and features of isolates]. | a rare food poisoning outbreak caused by s. oranienburg occurred at a junior high school athletic meet in kurashiki, okayama, in september 2005. the 70 patients included junior high school students, teachers and other school staff, and their families. this bacillus was isolated from stools of two employees and another in catered sandwiches. the cause of the outbreak was determined by evidence and epidemiological investigation to be sandwiches served at the athletic meet. biochemical features, se ... | 2007 | 17564111 |
| outbreak of healthcare-associated infection and colonization with multidrug-resistant salmonella enterica serovar senftenberg in florida. | in july 1999, a rare strain of multidrug-resistant salmonella enterica serovar senftenberg was isolated from the sputum of a trauma patient. over a 6-year period (1999-2005) in northeast florida, this salmonella serovar spread to 66 other patients in 16 different healthcare facilities as a result of frequent transfers of patients among institutions. to our knowledge, this is the first outbreak of healthcare-associated infection and colonization with a fluoroquinolone-resistant strain of s. senft ... | 2007 | 17564982 |
| molecular typing of salmonella enterica serovars enteritidis, corvallis, anatum and typhimurium from food and human stool samples in tunisia, 2001-2004. | during the period from 2001 to 2004, a total of 72 isolates of salmonella enterica serovars: anatum (n=40), enteritidis (n=18), corvallis (n=8), and typhimurium (n=6), of various origins (mainly food and diarrhoeagenic stool samples), were collected and further characterized by antibiotic resistance, plasmid analysis, and pulsed-field gel electrophoresis (pfge). forty-five isolates presented multidrug resistance to antibiotics. among which one s. enterica serovar anatum isolate was resistant to ... | 2008 | 17568477 |
| testing an ecological model for transmission of salmonella enterica in swine production ecosystems using genotyping data. | an ecological model for transmission of salmonella enterica in swine production ecosystems was developed, identifying host species, environmental reservoirs, and temporal, spatial, and functional (i.e., stage of production) dimensions. it was hypothesized that transmission was most likely within spatial and functional compartments, between hosts of the same species and abiotic compartments of the same type. eighteen swine production systems in illinois, usa, were sampled in four collection cycle ... | 2007 | 17570546 |
| antibody-quantum dot conjugates exhibit enhanced antibacterial effect vs. unconjugated quantum dots. | the effect of a 20-min exposure to antibody-quantum dot (ab-qd) conjugates on colony counts of escherichia coli was assessed by the spread-plate method and compared with exposure to unconjugated qds having only amine or carboxyl groups on their surfaces. under these conditions, ab-qd conjugates generally exhibited >90% reduction in colony-forming units as compared to untreated e. coli and e. coli treated with unconjugated qds after incubation for as long as 41 h. the antibacterial effect of ab-q ... | 2007 | 17571792 |
| expressed salmonella antigens within macrophages enhance the proliferation of cd4+ and cd8+ t lymphocytes by means of bystander dendritic cells. | atp-dependent lon protease-deficient salmonella enterica serovar typhimurium (strain cs2022) appeared to invade successfully the mesenteric lymph nodes (mln) and peyer's patches (pp) of balb/c mice and appeared to be easily eradicated by the host after oral immunization. as detected by flow cytometry, the population of major histocompatibility complex class i (mhc-i)-expressing macrophages and dendritic cells (dcs) was increased in the pp of mice immunized with cs2022 on day 6 after immunization ... | 2007 | 17573927 |
| mucosal lymphatic-derived gammadelta t cells respond early to experimental salmonella enterocolitis by increasing expression of il-2r alpha. | to better understand the roles of gammadelta t cells in mucosal infection, we utilized salmonella enterica serovar typhimurium (salmonella serovar typhimurium) infection in cattle as it closely approximates salmonella serovar typhimurium-induced enterocolitis in humans. protein and gene expression in alphabeta and gammadelta t cells derived from lymphatic ducts draining the gut mucosa in salmonella serovar typhimurium-infected calves were analyzed. in calves with enterocolitis, general gene expr ... | 2007 | 17574223 |
| salmonella enterica serovar typhimurium strain lacking pmrg-hm-d provides excellent protection against salmonellosis in murine typhoid model. | the superiority of live attenuated vaccines in systemic salmonellosis has been proven over killed and subunit vaccines, because of its ability to induce protective cell mediated immunity by cd8+ t cells. a live attenuated salmonella enterica serovar typhimurium vaccine has been developed by systematic site directed deletion of the pmrg-hm-d chromosomal genomic loci. this gene confers involved in antimicrobial peptide resistance and is involved in lps modification, both of which are the major imm ... | 2007 | 17574312 |
| domain organization and polarity of tail needle gp26 in the portal vertex structure of bacteriophage p22. | the attachment of tailed bacteriophages to the host cell wall as well as the penetration and injection of the viral genome into the host is mediated by the virion tail complex. in phage p22, a member of the podoviridae family that infects salmonella enterica, the tail contains an approximately 220 a elongated protein needle, previously identified as tail accessory factor gp26. together with tail factors gp4 and gp10, gp26 is critical to close the portal protein channel and retain the viral dna i ... | 2007 | 17574574 |
| intratumoral delivery and suppression of prostate tumor growth by attenuated salmonella enterica serovar typhimurium carrying plasmid-based small interfering rnas. | the facultative anaerobic, invasive salmonella enterica serovar typhimurium (s. typhimurium) has been shown to retard the growth of established tumors. we wondered if a more effective antitumor response could be achieved in vivo if these bacteria were used as tools for delivering specific molecular antitumor therapeutics. constitutively activated transcription factor signal transducer and activator of transcription 3 (stat3) promotes the survival of a number of human tumors. in this study, we in ... | 2007 | 17575154 |
| ordered expression of virulence genes in salmonella enterica serovar typhimurium. | using transcriptional promoter fusions, we investigated the expression of selected spi-1 and spi-2 genes of salmonella enterica serovar typhimurium (s. typhimurium). promoters of genes related to the invasion of the epithelial cell (hila, hilc, hild, invf, sica, sopa, sopb and sope2) were active in luria-bertani (lb) medium and lb with butyrate but were suppressed by bile salts and in glucose minimal (m9) medium. genes related to s. typhimurium intracellular survival (phop, ssra, ssab, ssag, sif ... | 2007 | 17575908 |
| [sanitary microbiology]. | sanitary microbiology is a science based on the detection of risks associated with the production, manufacture and consumption of foods and water. it has been established that environment facts determine the survival, growing and inactivation of the microorganisms. these risks are commonly associated with the presence of microbiological hazards and represent a serious problem from the public health viewpoint. the types of microorganisms presents in products will depend of the way they have been ... | 2006 | 17578095 |
| 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 |
| salmonella enterica subsp. enterica serovar agona infections in commercial pheasant flocks. | infections in pheasant flocks due to salmonella enterica subsp. enterica serovar agona occurred in a commercial pheasant farm in 1995 and 2000. s. enterica serovar agona isolates obtained from the affected birds in both years and an environmental sample from 1998 showed an identical pulsed-field gel electrophoresis pattern, indicating that the farm was continually contaminated with the strain during this period. nine hundred and seventy-three of 1850 birds (56.2%) died at 4 to 5 days of age in 1 ... | 2003 | 17585459 |
| 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 |
| salmonella enterica serotype typhimurium carrying hybrid virulence-resistance plasmids (puo-stvr): a new multidrug-resistant group endemic in spain. | the epidemiological impact in spain of an emerging group of multidrug-resistant salmonella enterica serotype typhimurium, characterized by the presence of virulence-resistance hybrid plasmids (termed puo-stvr) that are related to the s. typhimurium virulence plasmid pslt, was evaluated. adscription to the group was based on detection of the bla(oxa-1) gene (encoding ampicillin resistance) by pcr, and identification of a puo-stvr plasmid through hybridization with specific probes for virulence (s ... | 2008 | 17597002 |
| 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 |