Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| tissue selectivity of interferon-stimulated gene expression in mice infected with dam(+) versus dam(-) salmonella enterica serovar typhimurium strains. | the host interferon (ifn) system plays an important role in protection against microbial infections. salmonella enterica serovar typhimurium is highly virulent in the mouse model, whereas mutants that lack dna adenine methylase (dam(-)) are highly attenuated and elicit fully protective immune responses against murine typhoid fever. we examined the expression of ifn-responsive genes in several mouse tissues following infection with dam(+) or dam(-) salmonella. infection of mice with dam(+) salmon ... | 2002 | 12228285 |
| oral immunization with a salmonella enterica serovar typhi vaccine induces specific circulating mucosa-homing cd4(+) and cd8(+) t cells in humans. | the kinetics and homing characteristics of t-cell responses in humans after mucosal immunizations have not been well characterized. therefore, we have investigated the magnitude and duration of such responses as well as the homing receptor expression of antigen-specific peripheral blood t cells by using an oral model vaccine, i.e., the live, attenuated salmonella enterica serovar typhi vaccine (ty21a). eight volunteers were each given three doses of the vaccine 2 days apart, and blood samples, f ... | 2002 | 12228290 |
| characterization of a pore-forming cytotoxin expressed by salmonella enterica serovars typhi and paratyphi a. | cytolysin a (clya) is a pore-forming cytotoxic protein encoded by the clya gene that has been characterized so far only in escherichia coli. using dna sequence analysis and pcr, we established that clya is conserved in the human-specific typhoid salmonella enterica serovars typhi and paratyphi a and that the entire clya gene locus is absent in many other s. enterica serovars, including typhimurium. the gene products, designated clya(sty) and clya(spa), show >/=90% amino acid identity to e. coli ... | 2002 | 12228306 |
| bacterial contamination of animal feed and its relationship to human foodborne illness. | animal feed is at the beginning of the food safety chain in the "farm-to-fork" model. the emergence of variant creutzfeldt-jakob disease has raised awareness of the importance of contaminated animal feed, but less attention has been paid to the role of bacterial contamination of animal feed in human foodborne illness. in the united states, animal feed is frequently contaminated with non-typhi serotypes of salmonella enterica and may lead to infection or colonization of food animals. these bacter ... | 2002 | 12228823 |
| the prevalence and number of salmonella in sausages and their destruction by frying, grilling or barbecuing. | to determine the prevalence and number of salmonella and campylobacter in sausages and to evaluate their destruction during cooking. | 2002 | 12234336 |
| multidrug pump inhibitors uncover remarkable activity of plant antimicrobials. | plant antimicrobials are not used as systemic antibiotics at present. the main reason for this is their low level of activity, especially against gram-negative bacteria. the reported mic is often in the range of 100 to 1,000 micro g/ml, orders of magnitude higher than those of common broad-spectrum antibiotics from bacteria or fungi. major plant pathogens belong to the gram-negative bacteria, which makes the low level of activity of plant antimicrobials against this group of microorganisms puzzl ... | 2002 | 12234835 |
| dna sequence analysis of dna gyrase and dna topoisomerase iv quinolone resistance-determining regions of salmonella enterica serovar typhi and serovar paratyphi a. | the mutations that are responsible for fluoroquinolone resistance in the gyra, gyrb, parc, and pare genes of salmonella enterica serovar typhi and serovar paratyphi a were investigated. the sequences of the quinolone resistance-determining region of the gyra gene in clinical isolates which showed decreased susceptibilities to fluoroquinolones had a single mutation at either the ser-83 or the asp-87 codon, and no mutations were found in the gyrb, parc, and pare genes. | 2002 | 12234852 |
| a laboratory study of an inactivated bivalent iron restricted salmonella enterica serovars enteritidis and typhimurium dual vaccine against typhimurium challenge in chickens. | a commercial inactivated iron restricted salmonella typhimurium and salmonella enteritidis vaccine was used to vaccinate chicks at 1 day and again at 4 weeks of age, with challenge by a high and a low dose of s. typhimurium given either orally or by contact with seeder birds inoculated orally with a high dose of s. typhimurium. in all three challenge regimes, the shedding of challenge strain was reduced significantly (p < 0.05) in vaccinated birds compared with unvaccinated controls. vaccination ... | 2002 | 12243894 |
| multiresistant clones of salmonella enterica: the importance of dissemination. | increasing anitmicrobial resistance among foodborne pathogens has prompted calls for the reduction of anitmicrobial use in livestock to prevent future emergence or resistance. in the case of salmonella enterica, clonal dissemination may play a more critical role in regional changes in antimicrobial resistance in salmonellae than antimicrobial selection pressure. multi-resistant salmonella typhimurium definitive type 104 (mr-dt104) emerged from an unknown location and was disseminated globally du ... | 2002 | 12271270 |
| structural requirements of the mrna for intracistronic translation initiation of the enterobacterial infb gene. | the gene infb encodes the prokaryotic translation initiation factor if2, a central macromolecular component in the formation of the ribosomal 70s initiation complex. in escherichia coli, infb encodes three forms of if2: if2alpha, if2beta and if2gamma. the expression of if2beta and if2gamma is a tandem translation from intact infb mrna and not merely a translation of post-transcriptionally truncated mrna. the molecular mechanism responsible for the ribosomal recognition of the two intracistronic ... | 2002 | 12296821 |
| differences in attachment of salmonella enterica serovars and escherichia coli o157:h7 to alfalfa sprouts. | numerous salmonella enterica and escherichia coli o157:h7 outbreaks have been associated with contaminated sprouts. we examined how s. enterica serovars, e. coli serotypes, and nonpathogenic bacteria isolated from alfalfa sprouts grow on and adhere to alfalfa sprouts. growth on and adherence to sprouts were not significantly different among different serovars of s. enterica, but all s. enterica serovars grew on and adhered to alfalfa sprouts significantly better than e. coli o157:h7. e. coli o15 ... | 2002 | 12324317 |
| resuscitation of salmonella enterica serovar typhimurium and enterohemorrhagic escherichia coli from the viable but nonculturable state by heat-stable enterobacterial autoinducer. | salmonella enterica serovar typhimurium and enterohemorrhagic escherichia coli were stressed by prolonged incubation in water microcosms until it was no longer possible to observe colony formation when samples were plated on nonselective medium. overnight incubation of samples in nutrient-rich broth medium supplemented with growth factors, however, allowed resuscitation of stressed and viable but nonculturable cells so that subsequent plating yielded observable colonies for significantly extende ... | 2002 | 12324321 |
| plasmid pc present in salmonella enterica serovar enteritidis pt14b strains encodes a restriction modification system. | salmonella enterica serovar enteritidis (s. enteritidis) possesses plasmids of different sizes and roles. besides the serovar-specific virulence plasmid present in most field strains, s. enteritidis can harbour plasmids of low molecular mass whose biological role is poorly understood. we therefore sequenced plasmid pc present in s. enteritidis strains belonging to phage type pt14b. the size of plasmid was determined to be 5,269 bp and it was predicted to encode four open reading frames (orfs). t ... | 2002 | 12351230 |
| molecular follow-up of salmonella enterica subsp. enterica serovar agona infection in cattle and humans. | salmonella enterica subsp. enterica serovar agona was not frequently encountered in finland until an increase in rates of isolation among animal and feed was seen in 1994. a small outbreak among cattle farms in the regions of oulu and vaasa in northwestern finland in 1994-1995 included eight farms. after the outbreak, an increase in the number of serovar agona infections in humans was seen in 1999: the number of annual microbiologically confirmed cases in humans increased from about 10 from 1990 ... | 2002 | 12354860 |
| toll-like receptor 2 contributes to liver injury by salmonella infection through fas ligand expression on nkt cells in mice. | toll-like receptors (tlrs) for bacterial constitutes are expressed not only by phagocytes but also by some subsets of t cells. we previously reported that natural killer t cells (nkt cells) play an important role in liver injury induced by salmonella infection. in the present study, we investigated whether tlrs on nkt cells are involved in salmonella-induced liver injury. | 2002 | 12360487 |
| genetic structure of salmonella revealed by fragment analysis. | recently, the genus salmonella has been studied by multilocus enzyme electrophoresis (mlee) and three collections of strains defined by this method, sara, sarb and sarc, have been assembled to represent the genetic diversity of salmonella choleraesuis (commonly known as salmonella enterica) subspecies i and of the genus as a whole. the novel technique fluorescent amplified-fragment length polymorphism (faflp) analysis was applied to these collections to determine the genetic diversity of salmone ... | 2002 | 12361277 |
| in vivo and in vitro studies of genetic resistance to systemic salmonellosis in the chicken encoded by the sal1 locus. | a number of inbred lines of chickens have been shown to be resistant or susceptible to systemic salmonellosis caused by salmonella enterica serovar gallinarum in adult birds, or by s. enterica serovar enteritidis and s. enterica serovar typhimurium in young chicks. resistant lines show only moderate pathology and low mortality rates, whereas susceptible lines display extensive pathological changes and higher levels of mortality following salmonella infection. genetic resistance to salmonellosis ... | 2002 | 12361910 |
| salmonella sepsis caused by a platelet transfusion from a donor with a pet snake. | 2002 | 12362008 | |
| translocation of integron-associated resistance in a natural system: acquisition of resistance determinants by inc p and inc w plasmids from salmonella enterica typhimurium dt104. | salmonella enterica typhimurium dt104, 961368, a veterinary field isolate that encodes a chromosomal cluster of resistance genes as well as two integrons, was used to study the mobility of resistance cassettes (aada2 and pse-1) and nonintegron-associated resistance determinants (chloramphenicol and tetracycline). a range of natural plasmids was used as targets for the translocation of resistance. plasmids that acquired resistance from the dt104 chromosome were segregated by conjugation into esch ... | 2002 | 12363003 |
| differential accumulation of salmonella[cu, zn] superoxide dismutases sodci and sodcii in intracellular bacteria: correlation with their relative contribution to pathogenicity. | most salmonella enterica strains have two peri-plasmic [cu, zn] superoxide dismutases, sodci and sodcii, encoded by prophage and chromosomal genes respectively. both enzymes are thought to play a role in salmonella pathogenicity by intercepting reactive oxygen species produced by the host's innate immune response. to examine the apparent redundancy, we have compared the levels of epitope-tagged sodci and sodcii proteins in bacteria growing in vitro, as well as inside tissue culture cells and in ... | 2002 | 12366838 |
| microarray analysis identifies salmonella genes belonging to the low-shear modeled microgravity regulon. | the low-shear environment of optimized rotation suspension culture allows both eukaryotic and prokaryotic cells to assume physiologically relevant phenotypes that have led to significant advances in fundamental investigations of medical and biological importance. this culture environment has also been used to model microgravity for ground-based studies regarding the impact of space flight on eukaryotic and prokaryotic physiology. we have previously demonstrated that low-shear modeled microgravit ... | 2002 | 12370447 |
| salmonella typhimurium survival and viability is unaltered by suspended particles in freshwater. | rolling microcosm experiments were conducted to determine whether suspended particles affect the survival and viability of a model pathogen, salmonella choleraesuis, serotype typhimurium (american type culture collection no. 23567), in a freshwater microbial community. water from the duluth, mn harbor of lake superior (including native microorganisms) was inoculated with clay, silt, or flocculent organic particles in a range of concentrations and a streptomycin-resistant strain of s. typhimurium ... | 2002 | 12371189 |
| tightly regulated gene expression system in salmonella enterica serovar typhimurium. | a new salmonella enterica serovar typhimurium strain has been constructed to facilitate tightly regulated gene expression. arabinose-inducible and glucose-repressible expression of a t7 rna polymerase gene that has been integrated with an adjacent arac-p(bad) control element into the bacterial chromosome allows dynamic control of t7 promoter-driven rna transcription. | 2002 | 12374840 |
| expanding pyrimidine diphosphosugar libraries via structure-based nucleotidylyltransferase engineering. | in vitro "glycorandomization" is a chemoenzymatic approach for generating diverse libraries of glycosylated biomolecules based on natural product scaffolds. this technology makes use of engineered variants of specific enzymes affecting metabolite glycosylation, particularly nucleotidylyltransferases and glycosyltransferases. to expand the repertoire of udp/dtdp sugars readily available for glycorandomization, we now report a structure-based engineering approach to increase the diversity of alpha ... | 2002 | 12374866 |
| identification and characterization of snra, an inducible oxygen-insensitive nitroreductase in salmonella enterica serovar typhimurium ta1535. | the biological activity of many nitrosubstituted compounds, many of which are produced commercially or have been identified as environmental contaminants, is dependent on metabolic activation catalyzed by nitroreductases. in the current study, we have cloned a nitroreductase gene, salmonella typhimurium nitroreductase a (snra), from s. enterica serovar typhimurium strain ta1535, and characterized the purified gene product. snra is 240 amino acids in length and shares 87% sequence identity to the ... | 2002 | 12379462 |
| acquisition of mn(ii) in addition to fe(ii) is required for full virulence of salmonella enterica serovar typhimurium. | the roles of the genes feob (abc ferrous iron transporter), mnth (proton-dependent manganese transporter), and sitabcd (putative abc iron and/or manganese transporter) in salmonella pathogenicity were investigated by using mutant strains deficient in one, two, or three transporters. our results indicated that sitabcd encodes an important transporter of mn(ii) and fe(ii) which is required for full virulence in susceptible animals (nramp1(-/-)) and for replication inside nramp1(-/-) macrophages in ... | 2002 | 12379679 |
| the polysaccharide portion plays an indispensable role in salmonella lipopolysaccharide-induced activation of nf-kappab through human toll-like receptor 4. | the lipid a portion has been identified as the active center responsible for lipopolysaccharide (lps)-induced macrophage activation. however, we found that salmonella (salmonella enterica serovars abortusequi, minnesota, and typhimurium) lipid a is inactive in human macrophages, despite its lps being highly active. thus we investigated the critical role of polysaccharide in salmonella lps-induced activation of nf-kappab. in human monocytic cell line thp-1, salmonella lipid a and synthetic salmon ... | 2002 | 12379680 |
| salmonella enterica serovar typhi modulates cell surface expression of its receptor, the cystic fibrosis transmembrane conductance regulator, on the intestinal epithelium. | the cystic fibrosis transmembrane conductance regulator (cftr) protein is an epithelial receptor mediating the translocation of salmonella enterica serovar typhi to the gastric submucosa. since the level of cell surface cftr is directly related to the efficiency of serovar typhi translocation, the goal of this study was to measure cftr expression by the intestinal epithelium during infection. cftr protein initially present in the epithelial cell cytoplasm was rapidly trafficked to the plasma mem ... | 2002 | 12379722 |
| bactericidal activities of plant essential oils and some of their isolated constituents against campylobacter jejuni, escherichia coli, listeria monocytogenes, and salmonella enterica. | an improved method of sample preparation was used in a microplate assay to evaluate the bactericidal activity levels of 96 essential oils and 23 oil compounds against campylobacter jejuni, escherichia coli o157:h7, listeria monocytogenes, and salmonella enterica obtained from food and clinical sources. bactericidal activity (ba50) was defined as the percentage of the sample in the assay mixture that resulted in a 50% decrease in cfu relative to a buffer control. twenty-seven oils and 12 compound ... | 2002 | 12380738 |
| the effect of temperature on the growth and persistence of salmonella in fermented liquid pig feed. | two studies were conducted to investigate the effect of temperature on the fate of salmonella enterica subsp. enterica serovar typhimurium dt104:30 in fermented liquid pig feed. these were (1) by co-inoculation of feed with s. typhimurium dt104:30 and pediococcus pentosaceus, as the fermenting organism, and (2) by fermenting feed for 48, 72 or 96 h prior to inoculation with s. typhimurium dt104:30. in co-inoculated feed incubated at 20 degrees c, s. typhimurium dt104:30 persisted for at least 72 ... | 2002 | 12382689 |
| distribution and characterization of class 1 integrons in salmonella enterica serotype gallinarum biotype gallinarum. | fowl typhoid caused by salmonella enterica subsp. enterica serotype gallinarum biotype gallinarum is the most important chicken disease in korea. due to appearance of new or multiple antibiotics resistances in the recently isolated strains, it was difficult to control the disease using antibiotics in our country. therefore, the prevalence and genetic contents of class 1 integrons in biotype gallinarum isolated between 1992 and 2001 were investigated by pcr and direct sequencing, respectively. ou ... | 2002 | 12383639 |
| dunging gutters filled with fresh water in finishing barns had no effect on the prevalence of salmonella enterica on brazilian swine farms. | our aim was to assess the importance of dunging gutters filled with water in finishing barns for the prevalence of pigs shedding salmonella enterica. some finishing barns in brazil are provided with a dunging-gutter system which consists of a continuous water flow at the back of solid-floored adjacent pens. because there is transfer of faecal material between adjacent pens by water in this system and the faecal-oral route of transmission is so important for enteric pathogens, we tested the hypot ... | 2002 | 12383653 |
| investigation of the genetic diversity among isolates of salmonella enterica serovar dublin from animals and humans from england, wales and ireland. | to assess the degree of genetic diversity among animal salmonella dublin uk isolates, and to compare it with the genetic diversity found among human isolates from the same time period. | 2002 | 12392517 |
| interaction of human hematopoietic stem cells with bacterial pathogens. | primitive hematopoietic stem cells (hscs) in the bone marrow are rare pluripotent cells with the capacity to give rise to all lineages of blood cells. during commitment, progenitor cells are composed mainly of cells with the potential for differentiation into 1 or 2 lineages. this commitment involves the acquisition of specific growth factor receptors and the loss of others. viral and bacterial infections may lead to profound disturbance of hematopoiesis, which is possibly due to different susce ... | 2002 | 12393678 |
| the efficacy of salenvac, a salmonella enterica subsp. enterica serotype enteritidis iron-restricted bacterin vaccine, in laying chickens. | the protective effect of two vaccination regimes using salenvac, a commercially available iron-restricted salmonella enterica subsp. enterica serotype enteritidis pt4 bacterin vaccine, was verified in laying birds. immunization was intramuscular at 1 day old and again at 4 weeks of age (v2), or at 1 day and 4 weeks with a third dose at 18 weeks of age (v3). challenge s. enteritidis (5 to 7.5); x 10(7) colony forming units) was given intravenously at 8, 17, 23, 30 and 59 weeks of age. for all age ... | 2002 | 12396340 |
| prevalence of antimicrobial resistance among pigeon isolates of streptococcus gallolyticus, escherichia coli and salmonella enterica serotype typhimurium. | thirty-three streptococcus gallolyticus, 60 escherichia coli and 18 salmonella enterica serotype typhimurium var. copenhagen strains isolated from homing pigeons (columba livia) were tested for susceptibility to the antimicrobials most commonly used to treat pigeons. minimal inhibitory concentrations were determined using the agar dilution technique. aminoglycosides (gentamicin and kanamycin), trimethoprim and flumequine were relatively inactive against the streptococci tested. acquired tetracyc ... | 2002 | 12396341 |
| application of molecular methods for identification of strains classified as salmonella enterica serovar 6, 7:-:- by conventional serotyping. | an increased prevalence of salmonella enterica serovar tennessee (6, 7: z(29):-) was observed in broiler flocks in denmark in 1994 and a parallel increase in the prevalence of salmonella enterica serovar 6, 7:-:- was demonstrated, albeit at a lower level. plasmid profiling and ribotyping revealed similar genotypes and it was speculated that serovar 6, 7:-:- could represent a non-motile variant of salmonella tennessee. re-testing of the salmonella 6, 7:-:- isolates demonstrated the presence of fl ... | 2002 | 12396350 |
| the cytolytic effects of salmonella enterica serovar typhimurium on chicken heterophils. | mixing of chicken heterophils and salmonella enterica serovar typhimurium resulted in a rapid disappearance of heterophils when examined by scanning electron microscopy and trypan blue dye exclusion test. this disappearance appeared to be caused by a rapid degranulation of heterophils. | 2002 | 12396351 |
| isolation of salmonella from urban wild brown rats (rattus norvegicus) in the west midlands, uk. | a 6-month study was undertaken to investigate the prevalence of salmonella enterica in wild urban brown rats (rattus norvegicus) in the west midlands. samples were obtained of faecal droppings (n = 100) and from rectal swabs (n = 50) of rat carcases collected from active infestation sites. a subset of the rats (n = 25) had additional swab samples taken of the fur, paws and tail. five (10%) of the rectal swabs were positive for salmonella by direct plating onto xld media. no further samples were ... | 2002 | 12396533 |
| detection of a novel repeated sequence useful for epidemiological typing of pathogenic yersinia enterocolitica. | strains (n = 203) of yersinia species were used in genotyping and pcr experiments in order to evaluate the genotyping potential of the yeo:3rs probe. this probe comprises a 12.5 kb genomic fragment of the y. enterocolitica o:3 lipopolysaccharide o-antigen gene cluster cloned into plasmid pbr322. the genotyping potential of yeo:3rs was shown to reside in the region upstream of the o-antigen gene cluster, i.e., in the first 1.65 kb of the cloned genomic fragment that contains a repeated sequence ( ... | 2002 | 12398212 |
| metabolic flux in both the purine mononucleotide and histidine biosynthetic pathways can influence synthesis of the hydroxymethyl pyrimidine moiety of thiamine in salmonella enterica. | together, the biosyntheses of histidine, purines, and thiamine pyrophosphate (tpp) contain examples of convergent, divergent, and regulatory pathway integration. mutations in two purine biosynthetic genes (puri and purh) affect tpp biosynthesis due to flux through the purine and histidine pathways. the molecular genetic characterization of puri mutants and their respective pseudorevertants resulted in the conclusion that <1% of the wild-type activity of the puri enzyme was sufficient for thiamin ... | 2002 | 12399482 |
| inversions over the terminus region in salmonella and escherichia coli: is200s as the sites of homologous recombination inverting the chromosome of salmonella enterica serovar typhi. | genomic rearrangements (duplications and inversions) in enteric bacteria such as salmonella enterica serovar typhimurium lt2 and escherichia coli k12 are frequent (10(-3) to 10(-5)) in culture, but in wild-type strains these genomic rearrangements seldom survive. however, inversions commonly survive in the terminus of replication (ter) region, where bidirectional dna replication terminates; nucleotide sequences from s. enterica serovar typhimurium lt2, s. enterica serovar typhi ct18, e. coli k12 ... | 2002 | 12399489 |
| phenotypes of lexa mutations in salmonella enterica: evidence for a lethal lexa null phenotype due to the fels-2 prophage. | the lexa protein of escherichia coli represses the damage-inducible sos regulon, which includes genes for repair of dna. surprisingly, lexa null mutations in salmonella enterica are lethal even with a sula mutation, which corrects lexa lethality in e. coli. nine suppressors of lethality isolated in a sula mutant of s. enterica had lost the fels-2 prophage, and seven of these (which grew better) had also lost the gifsy-1 and gifsy-2 prophages. all three phage genomes included a homologue of the t ... | 2002 | 12399494 |
| characterization of the flgg operon of rhodobacter sphaeroides ws8 and its role in flagellum biosynthesis. | in this work, we show evidence regarding the functionality of a large cluster of flagellar genes in rhodobacter sphaeroides. the genes of this cluster, flgghijkl and orf-1, are mainly involved in the formation of the basal body, and flgk and flgl encode the hook-associated proteins hap1 and hap3. in general, these genes showed a good similarity as compared with those reported for salmonella enterica. however, flgj and flgk showed particular features that make them unique among the flagellar sequ ... | 2002 | 12401220 |
| isolation of spectinomycin resistance mutations in the 16s rrna of salmonella enterica serovar typhimurium and expression in escherichia coli and salmonella. | two single-base mutations in 16s rrna conferring high-level resistance to spectinomycin were isolated on a plasmid-borne copy of the rrnd operon from salmonella enterica serovar typhimurium. neither of the mutations (c1066u and c1192u) had appreciable effects on cell growth, but each had differential effects on resistance to spectinomycin and fusidic acid. both mutations also conferred resistance to spectinomycin in escherichia coli strains containing deletions of all seven chromosomal rrn opero ... | 2002 | 12402084 |
| identification and characterization of transferable integron-mediated antibiotic resistance among salmonella serovar typhimurium and salmonella serovar infantis isolates from 1991 to 2002. | 2002 | 12403914 | |
| viable but nonculturable salmonella species recovery and systemic infection in morphine-treated mice. | in vivo recovery and pathogenicity of salmonella enterica serovar oranienburg that became viable but nonculturable (vnc) in food were examined. vnc cells were completely eliminated in normal mice but caused systemic bacteremia and were subsequently lethal to morphine-treated mice. therefore, morphine-treated mice might be a useful bioassay for vnc salmonella species in implicated food items. | 2002 | 12404175 |
| validation of microbial recovery from disinfectants. | we evaluated the efficacy of different neutralizing solutions for use in disinfectant efficacy assays. our approach used comparisons between the recoveries of low inocula in different treatment populations. the challenge organisms employed were those described by the aoac for use in determining germicidal, tuberculocidal, sporicidal, and fungicidal activity of disinfectants. neutralizer efficacy (ne) ratios were determined by comparing the recovery of identical inocula from the neutralizing solu ... | 2002 | 12404721 |
| anti-salmonella activity of alkyl gallates. | a series of alkyl gallates (3,4,5-trihydroxybenzoates) was synthesized and tested for their antibacterial activity against salmonella choleraesuis. nonyl (c(9)) and octyl (c(8)) gallates were noted to be the most effective against this food-borne bacterium, each with a minimum bactericidal concentration (mbc) of 12.5 microg/ml, followed by decyl (c(10)) gallate, with a mbc of 25 microg/ml. dodecyl (c(12)) gallate exhibited activity against s. choleraesuis, with a mbc of 50 microg/ml. propyl (c(3 ... | 2002 | 12405763 |
| diffraction quality crystals of prd1, a 66-mda dsdna virus with an internal membrane. | it has proved difficult to obtain well diffracting single crystals of macromolecular complexes rich in lipid. we report here the path that has led to crystals of the bacteriophage prd1, a particle containing approximately 2,000 protein subunits from 18 different protein species, around 10 of which are integral membrane proteins associated with a host-derived lipid bilayer of some 12,500 lipid molecules. these crystals are capable of diffracting x-rays to bragg spacings below 4a. it is hoped that ... | 2002 | 12406692 |
| low-shear modeled microgravity alters the salmonella enterica serovar typhimurium stress response in an rpos-independent manner. | we have previously demonstrated that low-shear modeled microgravity (low-shear mmg) serves to enhance the virulence of a bacterial pathogen, salmonella enterica serovar typhimurium. the salmonella response to low-shear mmg involves a signaling pathway that we have termed the low-shear mmg stimulon, though the identities of the low-shear mmg stimulon genes and regulatory factors are not known. rpos is the primary sigma factor required for the expression of genes that are induced upon exposure to ... | 2002 | 12406731 |
| salmonellae in avian wildlife in norway from 1969 to 2000. | postmortem records of wild-living birds in norway with laboratory-confirmed findings of salmonella infection were summarized for the period from 1969 to 2000. salmonella spp. were isolated from 470 birds belonging to 26 species. the salmonella-positive birds included 441 small passerines, 15 gulls, 5 waterfowl, 4 birds of prey, 3 doves, and 2 crows. the bullfinch (pyrrhula pyrrhula) was by far the most frequently recorded species (54% of the cases). salmonella enterica serover typhimurium was re ... | 2002 | 12406754 |
| molecular epidemiology of salmonella enterica serovar typhimurium isolates determined by pulsed-field gel electrophoresis: comparison of isolates from avian wildlife, domestic animals, and the environment in norway. | the molecular epidemiology of 142 isolates of salmonella enterica serovar typhimurium from avian wildlife, domestic animals, and the environment in norway was investigated using pulsed-field gel electrophoresis (pfge) and computerized numerical analysis of the data. the bacterial isolates comprised 79 isolates from wild-living birds, including 46 small passerines and 26 gulls, and 63 isolates of nonavian origin, including 50 domestic animals and 13 environmental samples. thirteen main clusters w ... | 2002 | 12406755 |
| characterization of serracin p, a phage-tail-like bacteriocin, and its activity against erwinia amylovora, the fire blight pathogen. | serratia plymithicum j7 culture supernatant displayed activity against many pathogenic strains of erwinia amylovora, the causal agent of the most serious bacterial disease of apple and pear trees, fire blight, and against klebsiella pneumoniae, serratia liquefaciens, serratia marcescens, and pseudomonas fluorescens. this activity increased significantly upon induction with mitomycin c. a phage-tail-like bacteriocin, named serracin p, was purified from an induced culture supernatant of s. plymith ... | 2002 | 12406768 |
| molecular characterization of spm-1, a novel metallo-beta-lactamase isolated in latin america: report from the sentry antimicrobial surveillance programme. | the gene encoding the metallo-beta-lactamase spm-1 was cloned from a genomic library of pseudomonas aeruginosa strain 48-1997 a. the insert carrying spm-1 possessed a gc content of 47%, indicating that it is of non-pseudomonas origin. upstream of spm-1 there is a small open reading frame (orf), which is homologous to the lysr family of proteins (69% identity to the lysr protein from salmonella enterica serovar typhimurium). downstream of spm-1 there is the start of an orf, the product of which s ... | 2002 | 12407123 |
| how do bacteria resist human antimicrobial peptides? | cationic antimicrobial peptides (camps), such as defensins, cathelicidins and thrombocidins, are an important human defense mechanism, protecting skin and epithelia against invading microorganisms and assisting neutrophils and platelets. staphylococcus aureus, salmonella enterica and other bacterial pathogens have evolved countermeasures to limit the effectiveness of camps, including the repulsion of camps by reducing the net negative charge of the bacterial cell envelope through covalent modifi ... | 2002 | 11912025 |
| bacterial superoxide dismutase and virulence. | 2002 | 11912905 | |
| characterization of the campylobacter jejuni heptosyltransferase ii gene, waaf, provides genetic evidence that extracellular polysaccharide is lipid a core independent. | campylobacter jejuni produces both lipooligosaccharide (los) and a higher-molecular-weight polysaccharide that is believed to form a capsule. the role of these surface polysaccharides in c. jejuni-mediated enteric disease is unclear; however, epitopes associated with the los are linked to the development of neurological complications. in escherichia coli and salmonella enterica serovar typhimurium the waaf gene encodes a heptosyltransferase, which catalyzes the transfer of the second l-glycero-d ... | 2002 | 11914340 |
| gene transfer between salmonella enterica serovar typhimurium inside epithelial cells. | virulence and antibiotic resistance genes transfer between bacteria by bacterial conjugation. conjugation also mediates gene transfer from bacteria to eukaryotic organisms, including yeast and human cells. predicting when and where genes transfer by conjugation could enhance our understanding of the risks involved in the release of genetically modified organisms, including those being developed for use as vaccines. we report here that salmonella enterica serovar typhimurium conjugated inside cul ... | 2002 | 11914355 |
| salmonella effectors within a single pathogenicity island are differentially expressed and translocated by separate type iii secretion systems. | pathogenicity islands (pais) are large dna segments in the genomes of bacterial pathogens that encode virulence factors. five pais have been identified in the gram-negative bacterium salmonella enterica. two of these pais, salmonella pathogenicity island (spi)-1 and spi-2, encode type iii secretion systems (ttss), which are essential virulence determinants. these 'molecular syringes' inject effectors directly into the host cell, whereupon they manipulate host cell functions. these effectors are ... | 2002 | 11918798 |
| an evaluation of the performance of xld, dca, mlcb, and abc agars as direct plating media for the isolation of salmonella enterica from faeces. | to compare the performance of four media, singly and in combination, as direct plating media for the isolation of salmonella enterica from human faeces. | 2002 | 11919214 |
| salmonella enterica serovar enteritidis burden in broiler breeder chicks genetically associated with vaccine antibody response. | the relationship between antibody response to salmonella enteritidis vaccine and internal organ burden of s. enteritidis is not fully understood. the genetic relationship, therefore, between postchallenge s. enteritidis burden and antibody response to s. enteritidis vaccine was determined in broiler breeder chicks. sibling chicks from a broiler breeder male line were either inoculated with a pathogenic s. enteritidis or vaccinated with a commercial s. enteritidis vaccine. spleen, liver, cecal wa ... | 2002 | 11922346 |
| neutrophil phagocytosis following inoculation of salmonella choleraesuis into swine. | neutrophils are an important mediator of host defence, especially in early stages of infection. a major function of neutrophils is the uptake and killing of invading microbes. little is known about the effect of neutrophil activity on the pathogenesis and development of the carrier state in swine following infection with salmonella choleraesuis. a human whole-blood microassay using flow cytometry was modified to measure the effect of s. choleraesuis infection in vivo on the rate of ingestion, or ... | 2002 | 11922481 |
| comparison of gyra mutations, cyclohexane resistance, and the presence of class i integrons in salmonella enterica from farm animals in england and wales. | this study is focused on real-time detection of gyra mutations and of the presence of class i integrons in a panel of 100 veterinary isolates of salmonella enterica from farm animals. the isolates were selected on the basis of resistance to nalidixic acid, representing a variety of the most prevalent serotypes in england and wales. in addition, organic solvent (cyclohexane) resistance in these isolates was investigated in an attempt to elucidate the presence of efflux pump mechanisms. the most p ... | 2002 | 11923377 |
| identification of two phylogenetically related organisms from feces by pcr for detection of salmonella spp. | two previously reported pcr methods were evaluated to determine whether they are as sensitive and specific as conventional culture methods in detecting salmonella spp. from feces. bovine and equine feces were enriched overnight in brain heart infusion broth and assayed using pcr methods and primer sets described by other investigators. a total of 774 fecal specimens were tested using a primer set (inve-a primer set) that amplifies a region spanning the invasin e and a genes of salmonella enteric ... | 2002 | 11923378 |
| parotitis caused by salmonella choleraesuis varietas kunzendorf. | 2002 | 11928112 | |
| salmonella enterica serotype typhimurium shda is an outer membrane fibronectin-binding protein that is expressed in the intestine. | the shda gene is the only determinant known to be required for persistence of salmonella enterica serotype typhimurium (s. typhimurium) in the murine caecum and for efficient and prolonged shedding of the organism with the faeces. to study the biological activity of the shda protein, we examined its expression and binding activity. shda was not detected with anti-shda antiserum in s. typhimurium strain atcc14028 grown in vitro, suggesting that this protein is not expressed under standard conditi ... | 2002 | 11929540 |
| envelope instability in dna adenine methylase mutants of salmonella enterica. | mutants of salmonella enterica serovar typhimurium lacking dna adenine (dam) methylase show reduced secretion of invasion effectors encoded in the salmonella-pathogenicity island 1 (spi-1). concomitant with this alteration, a high number and quantity of extracellular proteins are detected in cultures of dam(-) mutants. this study shows by subcellular fractionation analysis that the presence of numerous extracellular proteins in cultures of dam(-) mutants is linked to an exacerbated release of me ... | 2002 | 11932461 |
| antimicrobial susceptibility of actinobacillus pleuropneumoniae, escherichia coli, and salmonella choleraesuis recovered from taiwanese swine. | minimum inhibition concentrations (mics) were determined for ampicillin, ceftiofur, cephalothin, chloramphenicol, enrofloxacin, gentamicin, lincomycin, lincospectin (lincomycin/spectinomycin), neomycin, premafloxacin, spectinomycin, sulfamethoxazole/trimethoprim, and tetracycline against a total of 180 isolates of actinobacillus pleuropneumoniae, escherichia coli, and salmonella choleraesuis (60 each) clinically isolated from pigs on farms in taiwan from 1994 to 1996. no more than 3 isolates per ... | 2002 | 11939337 |
| three-dimensional structure of the l-threonine-o-3-phosphate decarboxylase (cobd) enzyme from salmonella enterica. | the three-dimensional structure of the pyridoxal 5'-phosphate (plp)-dependent l-threonine-o-3-phosphate decarboxylase (cobd) from salmonella enterica is described here. this enzyme is responsible for synthesizing (r)-1-amino-2-propanol phosphate which is the precursor for the linkage between the nucleotide loop and the corrin ring in cobalamin. the molecule is a molecular dimer where each subunit consists of a large and small domain. overall the protein is very similar to the members of the fami ... | 2002 | 11939774 |
| population heterogeneity of salmonella enterica serotype typhimurium resulting from phase variation of the lpf operon in vitro and in vivo. | the lpf fimbrial operon oscillates between phase on and phase off expression states, thereby generating heterogeneity within s. enterica serotype typhimurium populations with regard to expression of long polar fimbrial antigens. to determine whether the proportion of lpf phase variants changes with growth conditions, the lpf phase on content of cultures was determined after in vitro and in vivo passage. after passage in luria-bertani (lb) broth for 120 generations, 96% of cells in a serotype typ ... | 2002 | 11948147 |
| mobility of a restriction-modification system revealed by its genetic contexts in three hosts. | the flow of genes among prokaryotes plays a fundamental role in shaping bacterial evolution, and restriction-modification systems can modulate this flow. however, relatively little is known about the distribution and movement of restriction-modification systems themselves. we have isolated and characterized the genes for restriction-modification systems from two species of salmonella, s. enterica serovar paratyphi a and s. enterica serovar bareilly. both systems are closely related to the pvuii ... | 2002 | 11948154 |
| a new chromosomal locus associated with gut-modulated phenotypes in salmonella enterica serotype typhimurium. | a cosmid dna library had been constructed previously from 40-kb fragments of genomic dna from a virulent invasive strain of salmonella enterica serotype typhimurium (tml) in an avirulent hypo-invasive typhimurium strain (lt7). selection of invasive clones from the library was attempted by iterative passage through a rabbit ileal organ culture. after the fourth passage, a clone, designated lt7(phc20-2), was isolated. exposure to both gut tissue and caco-2 cells enhanced the growth, invasiveness f ... | 2002 | 11871620 |
| extensive variation in the o-antigen gene cluster within one salmonella enterica serogroup reveals an unexpected complex history. | the 46 serogroups of salmonella enterica have different o-antigens, and each is thought to have a specific form of the o-antigen cluster. comparison of the 145 serovars of serogroup b revealed much more intraserogroup genetic diversity than expected. the o27 factor, due to an alpha 1-6 linkage between o units in place of the more common alpha 1-2 linkage and previously thought to be due to a converting bacteriophage, is now shown to be due to a wzy(alpha(1-6)) gene located within the major gene ... | 2002 | 11872718 |
| microsatellite markers linked to salmonella enterica serovar enteritidis vaccine response in young f1 broiler-cross chicks. | reduction in salmonella enteritidis (se) contamination is of importance for poultry production as well as for food safety. the objectives of this study were to identify potential genetic markers of antibody response to se vaccine in young broiler chicks and then to confirm this linkage in broiler-cross offspring, as well as to explore interactions of marker alleles with dam line and sex. the initial identification of suggestive quantitative trait loci (qtl) markers for antibody response to se va ... | 2002 | 11873827 |
| [isolation of a highly purified capsular polysaccharide from salmonella enterica serovar typhi (salmonella typhi)--vi-antigen and its use in serological diagnosis of typhoid fever]. | for use in differential diagnostics of typhoid fever, samples of the capsular polysaccharide from salmonella enterica serovar typhi (usually named vi-antigen) were isolated and characterized by physicochemical and serological methods. it was shown that only the sample of vi-antigen with the minimal (0.57%) admixture of the corresponding lipopolysaccharide (lps) from s. typhi retained a high serological activity in the tests with monoreceptor anti-vi sera. however, it exhibited a substantially we ... | 2002 | 11875976 |
| molecular epidemiological study of salmonella enterica serovar paratyphi b infections imported from turkey to western norway. | during the summer of 1999, several norwegian tourists returning from turkey became ill as a result of salmonella enterica serovar paratyphi b (s. paratyphi b) infection. we examined the s. paratyphi b isolates from 14 of these patients (10 from blood cultures, 4 from stool specimens) who were admitted to 2 hospitals in bergen, norway during august and september 1999. moreover, during the same period, a laboratory technician working at 1 of these hospitals was admitted with s. paratyphi b septice ... | 2002 | 11878291 |
| two different extended-spectrum beta-lactamases (esbls) in one of the first esbl-producing salmonella isolates in poland. | two extended-spectrum beta-lactamase (esbl)-producing salmonella isolates, salmonella enterica serovar enteritidis and salmonella enterica serovar typhimurium, were analyzed. both isolates produced the ctx-m-3 esbl; however, their bla(ctx-m-3) genes were located on different plasmids. the serovar typhimurium isolate also expressed another esbl, shv-2a, and probably the two esbl genes had been acquired independently by the strain. | 2002 | 11880450 |
| capsular vi polysaccharide antigen in salmonella enterica serovar typhi isolates. | 2002 | 11880463 | |
| the protective effect of alcoholic beverages on the occurrence of a salmonella food-borne outbreak. | there are few studies about the effect of alcoholic beverages in food-borne disease outbreaks. | 2002 | 11880766 |
| [characteristics of strains of salmonella enterica serovar typhimurium dt104 isolated in the slovak republic]. | from 1997 to 2000 in the slovak republic 8 strains of salmonella enterica serovar typhimurium dt104 were isolated from sporadic cases of human salmonellosis. four strains were multiresistant and three strains were sensitive to antibiotics. we investigated the influence of the cultivation medium (complete müeller-hinton, synthetic-staples) on growth, surface hydrophobicity and motility of the mentioned isolates. the hydrophobicity was evaluated by methods of adherence to the hydrocarbon xylene (b ... | 2002 | 11881300 |
| the role of two periplasmic copper- and zinc-cofactored superoxide dismutases in the virulence of salmonella choleraesuis. | periplasmic copper- and zinc-cofactored superoxide dismutases ([cu,zn]-sods, sodc) of several gram-negative pathogens can protect against superoxide-radical-mediated host defences, and thus contribute to virulence. this role has been previously defined for one [cu,zn]-sod in various salmonella serovars. following the recent discovery of a second periplasmic [cu,zn]-sod in salmonella, the effect of knockout mutations in one or both of the original sodc-1 and the new sodc-2 on the virulence of the ... | 2002 | 11882706 |
| trafficking of the salmonella vacuole in macrophages. | salmonella enterica is a facultative intracellular pathogen which can replicate in macrophages. intracellular salmonella exist in a membrane-bound compartment called the salmonella-containing vacuole. most studies on salmonella trafficking in relation to the endocytic pathway have concluded that the majority of salmonella-containing vacuoles do not interact extensively with late endosomes and lysosomes. numerous bacterial genes have been identified which are required for survival and replication ... | 2002 | 11886586 |
| dynamics of immune cell infiltration in the caecal lamina propria of chickens after neonatal infection with a salmonella enteritidis strain. | dynamics of leucocyte infiltration and bacterial invasion in the caecal wall were studied after oral infection of 2-day-old chicks with salmonella enterica ser. enteritidis. bacteria invaded the lamina propria of the caecal wall from 12h post-challenge onwards. bacteriological examination of internal organs (liver, spleen) showed a peak in salmonella bacteria at 3days post-infection, after which the number of bacteria decreased. immunohistochemistry revealed macrophages and t-lymphocytes invadin ... | 2002 | 11888650 |
| an outbreak of multidrug-resistant salmonella enterica subsp. enterica serotype typhimurium, dt104l linked to dried anchovy in singapore. | multidrug-resistant salmonella enterica subsp. enterica serotype typhimurium dt104l was first reported in singapore from mid-july to mid-october 2000. salmonella strains isolated from clinical laboratories were submitted to a reference laboratory for serotyping, phage-typing and pulsed-field gel electrophoresis (pfge) using xbai restriction endonuclease. an epidemiological investigation was conducted to determine the source of infection and mode of transmission using a structured questionnaire. ... | 2002 | 11895083 |
| immune responses to recombinant pneumococcal pspa antigen delivered by live attenuated salmonella enterica serovar typhimurium vaccine. | attenuated salmonella enterica serovar typhimurium expressing recombinant antigens from other pathogens elicits primarily a th1-type dominant immune response to both recombinant and salmonella antigens. the immunogenicity and appropriate subcellular location of the recombinant antigen in the salmonella vaccine strain may contribute to augmenting immune responses by facilitating adequate exposure of recombinant antigen to antigen-presenting cells for processing. to allow for secretion from gram-n ... | 2002 | 11895935 |
| host immune response to salmonella enterica serovar typhimurium infection in mice derived from wild strains. | studies of mouse models of endotoxemia and sepsis with gram-negative bacteria have shown that the host response is genetically controlled. mice infected with the gram-negative bacterium salmonella enterica serovar typhimurium exhibit marked genetic differences in disease manifestation, and the wild-derived strain mus musculus molossinus molf/ei is extremely susceptible to s. enterica serovar typhimurium. the kinetics of bacterial proliferation within the liver and the spleen and histological exa ... | 2002 | 11895964 |
| construction of a tetr-integrated salmonella enterica serovar typhi cvd908 strain that tightly controls expression of the major merozoite surface protein of plasmodium falciparum for applications in human vaccine production. | attenuated salmonella strains are an attractive live vector for delivery of a foreign antigen to the human immune system. however, the problem with this vector lies with plasmid segregation and the low level of expression of the foreign gene in vivo when constitutive expression is employed, leading to a diminished immune response. we have established inducible expressions of foreign genes in the salmonella enterica serovar typhi cvd908 vaccine strain using the tetracycline response regulatory pr ... | 2002 | 11895968 |
| specific entry of helicobacter pylori into cultured gastric epithelial cells via a zipper-like mechanism. | although helicobacter pylori has generally been considered an extracellular pathogen, a number of in vitro infection experiments and biopsy examinations have shown that it is capable of occasionally entering mammalian host cells. here, we characterized this entry process by using ags cells as a host cell model. in gentamicin protection-invasion assays, the number of h. pylori colonies recovered was lower than that for salmonella enterica serovar typhimurium x22, escherichia coli expressing inva, ... | 2002 | 11895977 |
| laboratory-scale preparation of soft cheese artificially contaminated with low levels of escherichia coli o157, listeria monocytogenes, and salmonella enterica serovars typhimurium, enteritidis, and dublin. | the production of cheese with incurred low levels of pathogenic microorganisms stressed by the production process was the aim of the study. a standard protocol for the preparation of artificially contaminated soft cheese on a laboratory scale was developed. milk for cheese preparation was artificially contaminated with pathogenic target microorganisms at low levels, between 1 and 10 cfu/ml. two strains of escherichia coli oi157:h7, two strains of listeria monocytogenes, and three salmonella spp. ... | 2002 | 11899950 |
| sero types, phage types and antibiotic susceptibilities of salmonella strains isolated from horses in the netherlands from 1993 to 2000. | we studied 232 salmonella strains from horses with salmonellosis in the netherlands, isolated in the period from 1993 to 2000 in order to provide insight in the dynamics of sero-, phage types (pt) and antibiotic susceptibilities over time. the strains were tested for susceptibility to seven antimicrobial agents using the agar diffusion method. in addition, the isolates were sero typed and salmonella enterica subspecies enterica typhimurium and enteritidis strains were further phage typed. s. typ ... | 2002 | 11900955 |
| salmonella enterica serotype typhimurium and its host-adapted variants. | 2002 | 11953356 | |
| genome-based identification of chromosomal regions specific for salmonella spp. | acquisition of genomic elements by horizontal gene transfer represents an important mechanism in the evolution of bacterial species. pathogenicity islands are a subset of horizontally acquired elements present in various pathogens. these elements are frequently located adjacent to trna genes. we performed a comparative genome analysis of salmonella enterica serovars typhi and typhimurium and escherichia coli and scanned trna loci for the presence of species-specific, horizontally acquired genomi ... | 2002 | 11953370 |
| a superoxide-hypersusceptible salmonella enterica serovar typhimurium mutant is attenuated but regains virulence in p47(phox-/-) mice. | salmonella enterica serovar typhimurium is a gram-negative, facultative intracellular pathogen that predominantly invades mononuclear phagocytes and is able to establish persistent infections. one of the innate defense mechanisms of phagocytic cells is the production of reactive oxygen species, including superoxide. s. enterica serovar typhimurium has evolved mechanisms to resist such radicals, and these mechanisms could be decisive in its ability to survive and replicate within macrophages. rec ... | 2002 | 11953403 |
| biofilm formation and interaction with the surfaces of gallstones by salmonella spp. | salmonellae can exist in an asymptomatic carrier state in the human gallbladder. individuals with gallstones are more likely to become typhoid carriers, and antibiotic treatments are often ineffectual against salmonella enterica serovar typhi in carriers with gallstones. therefore, we hypothesized that salmonella spp. form biofilms on the surfaces of gallstones, where the bacteria are protected from high concentrations of bile and antibiotics. a number of methods were utilized to examine biofilm ... | 2002 | 11953406 |
| antimicrobial resistance in salmonella enterica serovars enteritidis and typhimurium isolated from animals in korea: comparison of phenotypic and genotypic resistance characterization. | fourteen and 22 each of salmonella enteritidis and salmonella typhimurium (s. typhimurium) were isolated from animals from 1983 to 1999 in korea and tested for their antibiotic resistance patterns, phage types and resistance gene patterns. s. typhimurium isolates were highly resistant to streptomycin, sulfisoxazole and tetracycline, 95, 95 and 86%, respectively. the incidence of multiple antibiotic resistance (resistant to more than two drugs tested) of s. typhimurium isolates was extremely high ... | 2002 | 11955779 |
| differences between national reference laboratories of the european community in their ability to serotype salmonella species. | the capacity of national reference laboratories of the european union member states to correctly serotype salmonella strains was assessed in four collaborative studies on serotyping in the period 1995-1999. participants were asked to identify 20 strains in studies i, ii and iii and 16 strains in study iv, using the typing method routinely performed in their laboratory. in the first study, the strains to be identified belonged to salmonella enterica subsp. enterica, salamae or houtenae, while in ... | 2002 | 11957022 |
| lack of interaction of fluoroquinolones with lipopolysaccharides. | fluoroquinolones are known to chelate with di- and trivalent cations, and it has accordingly been claimed that they perturb the integrity of the outer membrane (om) of gram-negative bacteria. so far, chelation has not been assessed in biologically relevant test systems. therefore, we investigated the interaction of ciprofloxacin and moxifloxacin in the absence and presence of mg2+ with whole bacteria and isolated lipopolysaccharide (lps) from various rough mutant strains of salmonella enterica c ... | 2002 | 11959601 |
| characterization of a laboratory-derived, high-level ampicillin-resistant salmonella enterica serovar typhimurium strain that caused meningitis in an infant. | a salmonella enterica serovar typhimurium strain that harbored a plasmid carrying a tem-1-type beta-lactamase gene was isolated from the blood and cerebrospinal fluid of an infant with meningitis. this 3.2-kb plasmid was further characterized to be a nonconjugative pgem series cloning vector containing a foreign insert. the strain was likely laboratory derived and contaminated the environment before it caused the infection. | 2002 | 11959613 |
| salmonella enterica serotype typhimurium dt104 isolated from humans, united states, 1985, 1990, and 1995. | first isolated from an ill person in 1985, multidrug-resistant salmonella enterica serotype typhimurium dt104 emerged in the mid-1990s as a strain of salmonella frequently isolated from humans in the united states. we compared the integron content, plasmid profile, and xbai pulsed-field gel electrophoresis (pfge) patterns of multidrug-resistant s. typhimurium dt104 (mr-dt104) isolated from humans in the united states in 1985, 1990, and 1995. all isolates contained a 60-mda plasmid and had indist ... | 2002 | 11971772 |