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investigations of waterborne pathogens in eurasian beaver (castor fiber) from telemark county, southeast norway. 200111957376
coinfection of enteric helicobacter spp. and campylobacter spp. in cats.during a 6-year period, 64 of 227 commercially reared cats had microaerobic bacteria isolated from their feces. all the isolates were initially identified as campylobacter-like organisms based on biochemical and phenotypic characteristics. dna extractions from 51 of these isolates were subjected to pcr using primers specific for helicobacter spp. and campylobacter spp. of the isolates, 92% (47 of 51 isolates) were positive for campylobacter spp., 41% (21 of 51 isolates) were positive for helicob ...200111376052
evaluation of methods for subtyping campylobacter jejuni during an outbreak involving a food handler.in october 1998, the centers for disease control and prevention (cdc) assisted in an investigation of an outbreak of campylobacteriosis at a school in salina, kansas. twenty-two isolates were submitted from the kansas state public health laboratory to cdc, 9 associated with the outbreak and 13 epidemiologically unrelated sporadic isolates. pulsed-field gel electrophoresis (pfge) using smai and sali was initially used to validate the epidemiologic data. we then tested the ability of other subtypi ...200111427543
thermophilic campylobacters in surface water: a potential risk of campylobacteriosis.campylobacteriosis caused by campylobacter jejuni, campylobacter coli and campylobacter lari is one of the most frequently occurring acute gastroenteritis diseases in humans. an important risk factor is untreated drinking water. thermotolerant campylobacters were isolated from bø river water using 100-ml filtrate samples. campylobacters were isolated from 32 of 60 samples (53.3%). of the 75 strains isolated, 47 (62.7%) were detected using the enrichment procedure and 28 (37.2%) by direct plating ...200111798419
prevalence of salmonella, campylobacter and vtec on pig farms.four different pig farms were sampled for the prevalence of salmonella, campylobacter and verotoxigenic e. coli (vtec). pigs of different age groups and pigs of the same age were tested by taking rectal swabs. the farm environment was tested by examining overshoes, and the feed and drinking water in the pens. from a total of 215 rectal samples of individual pigs, 15 rectal samples taken from animals at the same farm were positive for salmonella. the salmonella status of the pigs at this farm dif ...200115954621
rapid detection of enterohemorrhagic escherichia coli by real-time pcr with fluorescent hybridization probes.in this report, we present a pcr protocol for rapid identification of enterohemorrhagic escherichia coli on a lightcycler instrument. in a multiplex assay, the genes encoding shiga toxin 1 and shiga toxin 2 are detected in a single reaction capillary. a complete analysis of up to 32 samples takes about 45 min.200111136804
competitive exclusion of heterologous campylobacter spp. in chicks.chicken and human isolates of campylobacter jejuni were used to provide oral challenge of day-old broiler chicks. the isolation ratio of the competing challenge strains was monitored and varied, depending upon the isolates used. a pcr-restriction fragment length polymorphism assay of the flagellin gene (flaa) was used to discriminate between the chick-colonizing isolates. our observations indicated that the selected c. jejuni colonizers dominated the niche provided by the chicken ceca. chicken i ...200111157253
systematic identification of selective essential genes in helicobacter pylori by genome prioritization and allelic replacement mutagenesis.a comparative genomic approach was used to identify helicobacter pylori 26695 open reading frames (orfs) which are conserved in h. pylori j99 but highly diverged in other eubacteria. a survey of selected pathways of central intermediary metabolism was also carried out, and genes with a potentially selective role in h. pylori were identified. forty-five orfs identified in these two analyses were screened using a rapid vector-free allelic replacement mutagenesis technique, and 33 were shown to be ...200111157938
clonal relationships among shigella serotypes suggested by cryptic flagellin gene polymorphism.the presence of cryptic flic alleles in the genomes of 120 strains representative of the four shigella species was investigated. one fragment was obtained by pcr amplification of flic, with a size varying from 1.2 to 3.2 kbp, depending on the species or serotype. after digestion with endonuclease hhai, the number of fragments in patterns varied from three to nine, with sizes of between 115 and 1,020 bp. patterns sharing most of their bands were grouped to constitute an f type. a total of 17 diff ...200111158126
molecular ecology of tetracycline resistance: development and validation of primers for detection of tetracycline resistance genes encoding ribosomal protection proteins.phylogenetic analysis of tetracycline resistance genes encoding the ribosomal protection proteins (rpps) revealed the monophyletic origin of these genes. the most deeply branching class, exemplified by tet and otra, consisted of genes from the antibiotic-producing organisms streptomyces rimosus and streptomyces lividans. with a high degree of confidence, the corresponding genes of the other seven classes (tet m, tet s, tet o, tet w, tet q, tet t, and tetb p) formed phylogenetically distinct sepa ...200111133424
novel lysophospholipase a secreted by legionella pneumophila.we show that legionella pneumophila possesses lysophospholipase a activity, which releases fatty acids from lysophosphatidylcholine. the nh2-terminal sequence of the enzyme contained fgdsls, corresponding to a catalytic domain in a recently described group of lipolytic enzymes. culture supernatants of a l. pneumophila pild mutant lost the ability to cleave lysophosphatidylcholine.200111222614
quinolone and macrolide resistance in campylobacter jejuni and c. coli: resistance mechanisms and trends in human isolates.the incidence of human campylobacter jejuni and c. coli infections has increased markedly in many parts of the world in the last decade as has the number of quinolone-resistant and, to a lesser extent, macrolide-resistant campylobacter strains causing infections. we review macrolide and quinolone resistance in campylobacter and track resistance trends in human clinical isolates in relation to use of these agents in food animals. susceptibility data suggest that erythromycin and other macrolides ...200111266291
antimicrobial properties of garlic oil against human enteric bacteria: evaluation of methodologies and comparisons with garlic oil sulfides and garlic powder.the antimicrobial effects of aqueous garlic extracts are well established but those of garlic oil (go) are little known. methodologies for estimating the antimicrobial activity of go were assessed and go, go sulfide constituents, and garlic powder (gp) were compared in tests against human enteric bacteria. test methodologies were identified as capable of producing underestimates of go activity. antimicrobial activity was greater in media lacking tryptone or cysteine, suggesting that, as for alli ...200111133485
multilocus sequence typing system for campylobacter jejuni.the gram-negative bacterium campylobacter jejuni has extensive reservoirs in livestock and the environment and is a frequent cause of gastroenteritis in humans. to date, the lack of (i) methods suitable for population genetic analysis and (ii) a universally accepted nomenclature has hindered studies of the epidemiology and population biology of this organism. here, a multilocus sequence typing (mlst) system for this organism is described, which exploits the genetic variation present in seven hou ...200111136741
use of pulsed-field gel electrophoresis and flagellin gene typing in identifying clonal groups of campylobacter jejuni and campylobacter coli in farm and clinical environments.although campylobacters have been isolated from a wide range of animal hosts, the association between campylobacters isolated from humans and animals in the farm environment is unclear. we used flagellin gene typing and pulsed-field gel electrophoresis (pfge) to investigate the genetic diversity among isolates from animals (cattle, sheep, and turkey) in farm environments and sporadic cases of campylobacteriosis in the same geographical area. forty-eight combined fla types were seen among the 315 ...200111282587
genotypic analysis of escherichia coli strains from poultry carcasses and their susceptibilities to antimicrobial agents.plasmid profiling and amplified fragment length polymorphism (aflp) analysis were used to genotype 50 escherichia coli strains from poultry carcasses. thirty different plasmid profiles were evident, and clustering of the aflp data showed that they were a distinctly heterogeneous group of strains. susceptibility testing against five antimicrobial agents used in the south african poultry industry showed all strains to be susceptible to danofloxacin and colistin, while the majority (96%) were resis ...200111282652
molecular characterization of invasive and noninvasive campylobacter jejuni and campylobacter coli isolates.campylobacter jejuni is one of the most common causes of bacterial diarrhea worldwide and is the primary bacterial cause of food-borne illness. adherence to and invasion of epithelial cells are the most important pathogenic mechanisms of campylobacter diarrhea. molecular characterization of invasive and noninvasive campylobacter isolates from children with diarrhea and symptom-free children was performed by random amplified polymorphic dna techniques (rapd). a distinct rapd profile with a dna ba ...200111283056
survival of campylobacter jejuni during stationary phase: evidence for the absence of a phenotypic stationary-phase response.when campylobacter jejuni nctc 11351 was grown microaerobically in rich medium at 39 degrees c, entry into stationary phase was followed by a rapid decline in viable numbers to leave a residual population of 1% of the maximum number or less. loss of viability was preceded by sublethal injury, which was seen as a loss of the ability to grow on media containing 0.1% sodium deoxycholate or 1% sodium chloride. resistance of cells to mild heat stress (50 degrees c) or aeration was greatest in exponen ...200111319108
study of the infectivity of saline-stored campylobacter jejuni for day-old chicks.the culturability of three campylobacter jejuni strains and their infectivity for day-old chicks were assessed following storage of the strains in saline. the potential for colonization of chicks was weakened during the storage period and terminated 3 to 4 weeks before the strains became nonculturable. the results from this study suggest that the role of starved and aged but still culturable campylobacters may be diminutive, but even more, that the role of viable but nonculturable stages in camp ...200111319130
recommendations of the subcommittee on the taxonomy of campylobacter and related bacteria.the icsb subcommittee on the taxonomy of campylobacter and related bacteria has discussed several contemporaneous issues and makes the following recommendations. (i) the reported synonymy between campylobacter coli and campylobacter hyoilei was based on valid taxonomic arguments. the subcommittee therefore discourages the use of the name c. hyoilei. (ii) the revised infrasubspecific nomenclature of campylobacter sputorum is endorsed. c sputorum is subdivided into c. sputorum biovar sputorum (cha ...200111321120
rapid pulsed-field gel electrophoresis protocol for subtyping of campylobacter jejuni.we developed a rapid pulsed-field gel electrophoresis (pfge) protocol for subtyping campylobacter isolates based on the standardized protocols used by pulsenet laboratories for the subtyping of other food-borne bacterial pathogens. various combinations of buffers, reagents, reaction conditions (e.g., cell suspension concentration, lysis time, lysis temperature, and restriction enzyme concentration), and electrophoretic parameters were evaluated in an effort to devise a protocol that is simple, r ...200111326009
role of flm locus in mesophilic aeromonas species adherence.the adherence mechanism of aeromonas caviae sch3n to hep-2 cells was initially investigated through four mini-tn5 mutants that showed a 10-fold decrease in adherence. these mutants lost motility, flagella, and their lipopolysaccharide (lps) o antigen (o-ag). three genes, flmb-neua-flmd, were found to be interrupted by the transposon insertions; additionally, two other genes, one lying upstream (flma) and one downstream (neub), were found to be clustered in the same operon. while the flma and flm ...200111119490
comparative study using amplified fragment length polymorphism fingerprinting, pcr genotyping, and phenotyping to differentiate campylobacter fetus strains isolated from animals.a collection of campylobacter fetus strains, including both c. fetus subsp. fetus and c. fetus subsp. venerealis, were phenotypically identified to the subspecies level and genotypically typed by pcr and amplified fragment length polymorphism (aflp) analysis. phenotypic subspecies determination methods were unreliable. genotyping of the strains by pcr and aflp showed a clear discrimination between the two subspecies.200111376071
changes in campylobacter jejuni and campylobacter coli carriage rates in the zenica region [correction of zenica canton] of bosnia and herzegovina in the pre- and postwar periods. 200111388169
modeling of combined processing steps for reducing escherichia coli o157:h7 populations in apple cider.probabilistic models were used as a systematic approach to describe the response of escherichia coli o157:h7 populations to combinations of commonly used preservation methods in unpasteurized apple cider. using a complete factorial experimental design, the effect of ph (3. 1 to 4.3), storage temperature and time (5 to 35 degrees c for 0 to 6 h or 12 h), preservatives (0, 0.05, or 0.1% potassium sorbate or sodium benzoate), and freeze-thaw (f-t; -20 degrees c, 48 h and 4 degrees c, 4 h) treatment ...200111133437
detection and initial characterization of novel capsular polysaccharide among diverse campylobacter jejuni strains using alcian blue dye.we have recently demonstrated that most strains of campylobacter jejuni produce capsular polysaccharide (cps), which can be detected by immunoblotting with homologous penner antisera on polyvinylidene difluoride membranes (a. v. karlyshev, d. linton, n. a. gregson, a. j. lastovica, and b. w. wren, mol. microbiol. 35:529-541, 2000). in this report, we describe a universal and rapid staining procedure using alcian blue for c. jejuni cps, which does not rely on the availability of antisera and iden ...200111136784
vacuolating cytotoxin of helicobacter pylori plays a role during colonization in a mouse model of infection.helicobacter pylori, the causative agent of gastritis and ulcer disease in humans, secretes a toxin called vaca (vacuolating cytotoxin) into culture supernatants. vaca was initially characterized and purified on the basis of its ability to induce the formation of intracellular vacuoles in tissue culture cells. h. pylori strains possessing different alleles of vaca differ in their ability to express active toxin. those strains expressing higher toxin levels are correlated with more severe gastric ...200111159961
allelic variation within helicobacter pylori baba and babb.helicobacter pylori strains show both geographic and disease-associated allelic variation. we investigated the diversity present in two genes, baba and babb, which are members of a paralogous family of outer membrane proteins. eleven family members within a single h. pylori strain, predicted to encode proteins with substantial n- and c-terminal similarity to each other, were classified as baba paralogues. in their central regions, most are less than 54% related to one another. examining the baba ...200111160014
macrolide resistance in campylobacter coli of animal origin in denmark. 200111221726
essential thioredoxin-dependent peroxiredoxin system from helicobacter pylori: genetic and kinetic characterization.helicobacter pylori, an oxygen-sensitive microaerophile, contains an alkyl hydroperoxide reductase homologue (ahpc, hp1563) that is more closely related to 2-cys peroxiredoxins of higher organisms than to most other eubacterial ahpc proteins. allelic replacement mutagenesis revealed ahpc to be essential, suggesting a critical role for ahpc in defending h. pylori against oxygen toxicity. characterization of the ahpc promoter region divulged two putative regulatory elements and identified the tran ...200111222594
development of a ceue-based multiplex polymerase chain reaction (pcr) assay for direct detection and differentiation of campylobacter jejuni and campylobacter coli in thailand.a novel ceue-based multiplex pcr system was developed as an efficient diagnostics test to detect and differentiate c. jejuni and c. coli. there is no cross reactivity between c. jejuni and c. coli. in addition, the assay does not produce a positive signal from other enteric bacteria including salmonella, shigella and escherichia coli strains. campylobacter detection sensitivity was determined to be equivalent to previously reported pcr for other enteric bacteria. we also noticed that silicon dio ...200111448558
evidence for a genetically stable strain of campylobacter jejuni.the genetic stability of selected epidemiologically linked strains of campylobacter jejuni during outbreak situations was investigated by using subtyping techniques. strains isolated from geographically related chicken flock outbreaks in 1998 and from a human outbreak in 1981 were investigated. there was little similarity in the strains obtained from the different chicken flock outbreaks; however, the strains from each of three chicken outbreaks, including strains isolated from various environme ...200111229909
iron-dependent transcription of the frpb gene of helicobacter pylori is controlled by the fur repressor protein.we have overexpressed and purified the helicobacter pylori fur protein and analyzed its interaction with the intergenic regions of divergent genes involved in iron uptake (frpb and ceue) and oxygen radical detoxification (kata and tsaa). dnase i footprint analysis showed that fur binds specifically to a high-affinity site overlapping the p(frpb) promoter and to low-affinity sites located upstream from promoters within both the frpb-kata and ceue-tsaa intergenic regions. construction of an isogen ...200111466300
antibody responses to campylobacter infections determined by an enzyme-linked immunosorbent assay: 2-year follow-up study of 210 patients.an enzyme-linked immunosorbent assay (elisa) was adapted to measure immunoglobulin g (igg), igm, and iga classes of human serum antibody to campylobacter jejuni and campylobacter coli. heat-stable antigen, a combination of c. jejuni serotype o:1,44 and o:53 in the ratio 1:1, was used as a coating antigen in the elisa test. a total of 631 sera from 210 patients with verified campylobacter enteritis were examined at various intervals after infection, and a control group of 164 sera were tested to ...200111238214
a genomic island in pseudomonas aeruginosa carries the determinants of flagellin glycosylation.protein glycosylation has been long recognized as an important posttranslational modification process in eukaryotic cells. glycoproteins, predominantly secreted or surface localized, have also been identified in bacteria. we have identified a cluster of 14 genes, encoding the determinants of the flagellin glycosylation machinery in pseudomonas aeruginosa pak, which we called the flagellin glycosylation island. flagellin glycosylation can be detected only in bacteria expressing the a-type flagell ...200111481492
helicobacter pylori resists phagocytosis by macrophages: quantitative assessment by confocal microscopy and fluorescence-activated cell sorting.helicobacter pylori infection of the stomach epithelium is characterized by an infiltration of polymorphonuclear and mononuclear cells. these immune cells contribute to mucosal damage which may eventually lead to gastritis, peptic ulcer, gastric cancer, and/or malt-associated gastric lymphoma. here we show that h. pylori inhibits its own uptake, as well as in trans the phagocytosis of neisseria gonorrhoeae, by human and murine macrophages. this antiphagocytic activity is dependent on the presenc ...200111254625
report a case of campylobacter coli bacteremia in a patient with gastro-enteritis. 200011484426
national surveillance of campylobacter in broilers at slaughter in denmark in 1998.a surveillance study for thermophilic campylobacter spp. in broiler flocks was carried out for the year 1998 in denmark. the study included examinations of 4286 broiler flocks comprising samples from 57,000 birds. overall, a flock prevalence of 46.0% was recorded. the species distribution was campylobacter jejuni 86%, campylobacter coli 11%, campylobacter lari 1%, other not further diagnosed species 2%. the prevalence was significantly higher in the period from june to october (3.2 < odds ratio ...200011195660
identification of taxonomic and epidemiological relationships among campylobacter species by numerical analysis of aflp profiles.amplified fragment length polymorphism (aflp)-based profiling was performed on 138 strains representing all named campylobacter species and subspecies. profiles of 15/16 species comprised 6 to greater than 100 fragments and were subjected to numerical analysis. the mean similarity of 48 duplicate, outbreak and/or 'identical' strain profiles exceeded 94%. species were clearly distinguished at the 17.90% similarity (s-) level in the dendrogram. subspecies of campylobacter jejuni and campylobacter ...200011094296
purification, characterization and sequence analysis of omp50,a new porin isolated from campylobacter jejuni.a novel pore-forming protein identified in campylobacter was purified by ion-exchange chromatography and named omp50 according to both its molecular mass and its outer membrane localization. we observed a pore-forming ability of omp50 after re-incorporation into artificial membranes. the protein induced cation-selective channels with major conductance values of 50-60 ps in 1 m nacl. n-terminal sequencing allowed us to identify the predicted coding sequence cj1170c from the campylobacter jejuni g ...200011104668
evaluation of a pcr primer based on the isocitrate dehydrogenase gene for detection of helicobacter pylori in feces.in order to improve detection and identification of helicobacter pylori in highly contaminated samples, we evaluated new specific primers based on the dna base sequence within the isocitrate dehydrogenase (icd) gene to amplify a 1,200-bp dna segment. the specificity of the icd primer was tested against dna derived from various bacteria, including 7 helicobacter species and a panel of 1 gram-variable, 2 gram-positive, and 16 gram-negative bacteria, as well as dna from houseflies and feces from h. ...200011015397
detection and characterization of autoagglutination activity by campylobacter jejuni.in several gram-negative bacterial pathogens, autoagglutination (aag) activity is a marker for interaction with host cells and virulence. campylobacter jejuni strains also show aag, but this property varies considerably among strains. to examine the characteristics of c. jejuni aag, we developed a quantitative in vitro assay. for strain 81-176, which shows high aag, activity was optimal for cells grown for < or = 24 h, was independent of growth temperature, and was best measured for cells suspen ...200011035721
susceptibility to secondary bacterial infections in growing pigs as an early response in ochratoxicosis.mycotoxic nephropathy was induced in twelve 14 kg pigs fed a dietary component, moulded by aspergillus ochraceus and contributing ochratoxin a at 1 or 3 ppm for up to 3 weeks. concurrently, salmonellosis arose spontaneously in all six animals treated at 3 ppm and all died between days 15 and 17. two of the six pigs in the 1 ppm group died similarly but the rest, and all of six control animals, were unaffected. clinical biochemistry and histology revealed changes typical of renal ochratoxicosis i ...200010987179
involvement of a plasmid in virulence of campylobacter jejuni 81-176.campylobacter jejuni strain 81-176 contains two, previously undescribed plasmids, each of which is approximately 35 kb in size. although one of the plasmids, termed ptet, carries a teto gene, conjugative transfer of tetracycline resistance to another strain of c. jejuni could not be demonstrated. partial sequence analysis of the second plasmid, pvir, revealed the presence of four open reading frames which encode proteins with significant sequence similarity to helicobacter pylori proteins, inclu ...200010899834
genotyping of clinical and chicken isolates of campylobacter jejuni and campylobacter coli.genomic dna from 58 strains of campylobacter made up of 48 campylobacter jejuni and ten campylobacter coli were digested with sma i and analysed by pulsed-field gel electrophoresis (pfge). the cleavage of dna by sma i gave 22 distinct hybridization patterns. the two campylobacter species were subtyped by pfge. the average genomic size for c. jejuni by sma i digestion was 1.73 mb, while that of c. coli gave 1.7 mb. results from this study indicate that pfge analysis by sma i digested genomic dna ...200011077971
campylobacter jejuni cytolethal distending toxin mediates release of interleukin-8 from intestinal epithelial cells.live cells of campylobacter jejuni and campylobacter coli can induce release of interleukin-8 (il-8) from int407 cells. additionally, membrane fractions of c. jejuni 81-176, but not membrane fractions of c. coli strains, can also induce release of il-8. membrane preparations from 81-176 mutants defective in any of the three membrane-associated protein subunits of cytolethal distending toxin (cdt) were unable to induce il-8. the presence of the three cdt genes on a shuttle plasmid in trans restor ...200011083762
sialylation of lipooligosaccharide cores affects immunogenicity and serum resistance of campylobacter jejuni.three genes involved in biosynthesis of the lipooligosaccharide (los) core of campylobacter jejuni msc57360, the type strain of the hs:1 serotype, whose structure mimics gm(2) ganglioside, have been cloned and characterized. mutation of genes encoding proteins with homology to a sialyl transferase (cstii) and a putative n-acetylmannosamine synthetase (neuc1), part of the biosynthetic pathway of n-acetylneuraminic acid (neunac), have identical phenotypes. the los cores of these mutants display id ...200011083778
differentiation of clinical helicobacter pullorum isolates from related helicobacter and campylobacter species.helicobacter pullorum, first detected in the liver and intestinal contents of poultry, was defined as a new species in 1994. this organism has since been isolated from humans with gastroenteritis. phenotypic as well as genotypic methods have been used to identify h. pullorum associated with cases of human disease.200010971678
characterization of gyra mutations associated with fluoroquinolone resistance in campylobacter coli by dna sequence analysis and mama pcr.increasing numbers of fluoroquinolone-resistant campylobacter coli isolates received at the minnesota state public health laboratory and at the centers for disease control and prevention have been a cause for concern. the gyra quinolone resistance-determining regions of several fluoroquinolone-resistant isolates were sequenced to examine the mechanism of resistance. ciprofloxacin-resistant c. coli isolates examined by dna sequencing had a thr-86 to ile (act-->att) gyra mutation, leading to resis ...200010981681
role of catalase in campylobacter jejuni intracellular survival.the ability of campylobacter jejuni to penetrate normally nonphagocytic host cells is believed to be a key virulence determinant. recently, kinetics of c. jejuni intracellular survival have been described and indicate that the bacterium can persist and multiply within epithelial cells and macrophages in vitro. studies conducted by pesci et al. indicate that superoxide dismutase contributes to intraepithelial cell survival, as isogenic sod mutants are 12-fold more sensitive to intracellular killi ...200011035743
genetics of swarming motility in salmonella enterica serovar typhimurium: critical role for lipopolysaccharide.salmonella enterica serovar typhimurium can differentiate into hyperflagellated swarmer cells on agar of an appropriate consistency (0.5 to 0.8%), allowing efficient colonization of the growth surface. flagella are essential for this form of motility. in order to identify genes involved in swarming, we carried out extensive transposon mutagenesis of serovar typhimurium, screening for those that had functional flagella yet were unable to swarm. a majority of these mutants were defective in lipopo ...200011053374
characterization of a novel outer membrane hemin-binding protein of porphyromonas gingivalis.porphyromonas gingivalis is a gram-negative, anaerobic coccobacillus that has been implicated as a major etiological agent in the development of chronic periodontitis. in this paper, we report the characterization of a protein, ihtb (iron heme transport; formerly designated pga30), that is an outer membrane hemin-binding protein potentially involved in iron assimilation by p. gingivalis. ihtb was localized to the cell surface of p. gingivalis by western blot analysis of a sarkosyl-insoluble oute ...200011053391
helicobacter canadensis sp. nov. isolated from humans with diarrhea as an example of an emerging pathogen.we recently analyzed 11 helicobacter isolates cultured from diarrhea patients in canada. these isolates had been characterized biochemically by restriction fragment length polymorphism (rflp; alui, hhai) analysis and by fatty-acid analysis as helicobacter pullorum. however, four of the isolates differed biochemically from h. pullorum by their inability to hydrolyze indoxyl acetate and their resistance to nalidixic acid. using complete 16s rrna analysis, we determined that these four strains clus ...200010878041
switching of flagellar motility in helicobacter pylori by reversible length variation of a short homopolymeric sequence repeat in flip, a gene encoding a basal body protein.the genome of helicobacter pylori contains numerous simple nucleotide repeats that have been proposed to have regulatory functions and to compensate for the conspicuous dearth of master regulatory pathways in this highly host-adapted bacterium. h. pylori strain 26695, whose genomic sequence was determined by the institute for genomic research (tigr), contains a repeat of nine cytidines in the flip flagellar basal body gene that splits the open reading frame in two parts. in this work, we demonst ...200010899861
rapid detection of campylobacter jejuni in stool specimens by an enzyme immunoassay and surveillance for campylobacter upsaliensis in the greater salt lake city area.the alexon-trend, inc. (ramsey, minn.), prospect campylobacter microplate assay was compared with culture on a campy-cva plate (remel, lenexa, kans.) and blood-free campylobacter agar with cefoperazone (20 microg/ml), amphotericin b (10 microg/ml), and teicoplanin (4 microg/ml) (cat medium; oxoid limited, hampshire, england) with 631 patient stool samples. the cat medium was used to isolate campylobacter upsaliensis. the enzyme immunoassay (eia) had a sensitivity and a specificity of 89 and 99%, ...200010921981
slaughter pigs are commonly infected by closely related but distinct gastric ulcerative lesion-inducing gastrospirilla.an association between (unculturable) gastrospirillum-like organisms (glo) and ulcerative lesions in the pars oesophagea in stomachs of swine has been claimed. in dogs glo detected by microscopy may represent several helicobacter species or subspecies. therefore we investigated which helicobacter spp. are present in stomachs of swine and their possible association with ulcerative lesions of the pars oesophagea. the presence of helicobacter spp. in the antrum and pars oesophagea in 122 stomachs o ...200010878060
antibody to heat shock protein can be used for early serological monitoring of helicobacter pylori eradication treatment.infection with helicobacter pylori induces humoral immune responses against various antigens of the bacterium. heat shock proteins (hsps) are immunodominant antigens in various diseases including h. pylori infection. in the present study, we measured the anti-hsp antibody titers in 42 patients with h. pylori-infected peptic ulcers during a bacterial eradication study. the patients were treated with a proton pump inhibitor and antimicrobial agents to eradicate the organism. their sera were obtain ...200010882654
detection of thermophilic campylobacter from sparrows by multiplex pcr: the role of sparrows as a source of contamination of broilers with campylobacter.the best combination of primers and the annealing temperature of multiplex pcr for campylobacter jejuni, campylobacter coli, and campylobacter lari were examined. the multiplex pcr was able to detect type strains of the three species. all results of identification of wild strains (30 strains of c. jejuni, 20 strains of c. coli, and 4 strains of c. lari) by the multiplex pcr coincided with those of the conventional biochemical identification tests, suggesting that the multiplex pcr can simultaneo ...200011193345
development of a fluorogenic 5' nuclease pcr assay for detection of the ail gene of pathogenic yersinia enterocolitica.in this report we describe the development and evaluation of a fluorogenic pcr assay for the detection of pathogenic yersinia enterocolitica. the assay targets the chromosomally encoded attachment and invasion gene, ail. three primer-probe sets (tm1, tm2, and tm3) amplifying different, yet overlapping, regions of ail were examined for their specificity and sensitivity. all three primer-probe sets were able to detect between 0.25 and 0.5 pg of purified y. enterocolitica dna. tm1 identified all 26 ...200010966386
comparative fingerprinting analysis of campylobacter jejuni subsp. jejuni strains by amplified-fragment length polymorphism genotyping.amplified-fragment length polymorphism (aflp) analysis with the endonucleases bglii and mfei was used to genotype 91 campylobacter jejuni subsp. jejuni strains from outbreaks and sporadic cases. aflp-generated fragments were labeled with fluorescent dye and separated by capillary electrophoresis. the software packages genescan and gelcompar ii were used to calculate aflp pattern similarities and to investigate phylogenetic relationships among the genotyped strains. the aflp method was compared w ...200010970387
automated 5' nuclease pcr assay for identification of salmonella enterica.a simple and ready-to-go test based on a 5' nuclease (taqman) pcr technique was developed for identification of presumptive salmonella enterica isolates. the results were compared with those of conventional methods. the taqman assay was evaluated for its ability to accurately detect 210 s. enterica isolates, including 100 problematic "rough" isolates. an internal positive control was designed to use the same salmonella primers for amplification of a spiked nonrelevant template (116 bp) in the sa ...200010970396
roles of fe superoxide dismutase and catalase in resistance of campylobacter coli to freeze-thaw stress.we demonstrated that oxidative stress plays a role in freeze-thaw-induced killing of campylobacter coli following analysis of mutants deficient in key antioxidant functions. superoxide anions, but not h(2)o(2), were formed during the freeze-thaw process. however, a failure to detoxify superoxide anions may lead to spontaneous disproportionation of the radicals to h(2)o(2).200010877815
antibiotic resistance in campylobacter strains isolated from animals, foods, and humans in spain in 1997-1998.colonization by campylobacter strains was investigated in human, broiler, and pig fecal samples from 1997-1998, as well as in foods of animal origin, and antibiotic susceptibility testing was carried out for these strains. campylobacter strains were isolated in the foods of animal origin (55 of 101 samples; 54.4%), intestinal samples from broilers (85 of 105; 81%), and pigs (40 of 45; 88.9%). a total of 641 campylobacter strains were isolated from 8,636 human fecal samples of clinical origin (7. ...200010639348
a novel action of the proton pump inhibitor rabeprazole and its thioether derivative against the motility of helicobacter pylori.the motility of helicobacter pylori was maximum at 37 degrees c and at ph 6. a newly developed proton pump inhibitor, rabeprazole (rpz), and its thioether derivative (rpz-th) markedly inhibited the motility of h. pylori. the concentrations of the drug necessary to inhibit 50% of the motility were 0.25, 16, 16, and >64 microgram/ml for rpz-th, rpz, lansoprazole, and omeprazole, respectively. no such inhibitory effects were observed with h(2) blockers or anti-h. pylori agents. the motilities of ca ...200011036024
milkborne campylobacter infection in hungary.in april 1998, an annual 2-day animal farm sale was held in hódmezóvásárhely, where 500 to 600 visitors consumed unpasteurized milk. the first signs of disease began 2 days after the end of the sale. fifty-two people from a wide age range fell ill, primarily with inflammatory enteritis. these cases included 34 with campylobacter positivity: 30 with campylobacter jejuni and 4 with campylobacter coli. environmental samples (raw milk, udder swabs, and rectal swabs from 12 cows in the suspected herd ...200011041145
improved repetitive-element pcr fingerprinting of salmonella enterica with the use of extremely elevated annealing temperatures.modified thermal cycling conditions were explored in an effort to improve the reproducibility and resolving power of repetitive-element pcr (rep-pcr) fingerprinting. assay performance was rigorously evaluated under standard and modified cycling conditions, using as a test set 12 strains putatively representing 12 serovars of salmonella enterica. for all three fingerprint types (eric2, boxa1r, and composite fingerprints), the use of extremely elevated annealing temperatures plus an initial "touch ...200010702502
identification of ciprofloxacin-resistant campylobacter jejuni by use of a fluorogenic pcr assay.fluoroquinolones are one class of antimicrobial agents commonly used to treat severe campylobacter jejuni infection. c. jejuni strains resistant to high levels of the fluoroquinolone ciprofloxacin (mic >/=16 microg/ml) have been predominantly characterized with a c-->t transition in codon 86 of gyra. the gyra gene encodes one subunit of dna gyrase, which is a primary target for fluoroquinolone antibiotics. this study establishes a rapid pcr-based taqman method for identifying ciprofloxacin-resis ...200011060054
serum amyloid p component bound to gram-negative bacteria prevents lipopolysaccharide-mediated classical pathway complement activation.although serum amyloid p component (sap) is known to bind many ligands, its biological function is not yet clear. recently, it was demonstrated that sap binds to lipopolysaccharide (lps). in the present study, sap was shown to bind to gram-negative bacteria expressing short types of lps or lipo-oligosaccharide (los), such as salmonella enterica serovar copenhagen re and escherichia coli j5, and also to clinical isolates of haemophilus influenzae. it was hypothesized that sap binds to the bacteri ...200010722560
chronic atrophic gastritis in scid mice experimentally infected with campylobacter fetus.campylobacter fetus is a cause of enteritis and invasive extraintestinal disease in humans. in order to develop an animal model of c. fetus infection, outbred icr scid mice were orally challenged with a clinical isolate of c. fetus. the stomachs of scid mice were heavily colonized with c. fetus, and colonization was associated with the development of chronic atrophic gastritis. this lesion was characterized by an inflammatory infiltrate of granulocytes and macrophages that over time resulted in ...200010722608
detection and differentiation of campylobacter jejuni and campylobacter coli in broiler chicken samples using a pcr/dna probe membrane based colorimetric detection assay.campylobacter enteritis in humans has been linked to consumption of poultry meat. surveys show that 30-100% of poultry harbour campylobacter as normal flora of the digestive tract which indicates a need to identify prevalent organism types in flocks and trace their epidemiology. in this study we describe a campylobacter genus specific polymerase chain reaction (pcr) assay, amplifying the 16 s-23 s rrna intergenic spacer region with an internal campylobacter genus specific dna probe and species s ...200010725058
lipopolysaccharides of a campylobacter coli isolate from a patient with guillain-barré syndrome display ganglioside mimicry.campylobacter coli was isolated from a patient with severe, axonal type guillain-barré syndrome (gbs). the patient's serum was tested by elisa for glycolipid antibodies and showed a high titer of igg antibodies to asialo-gm1 (ga1) and gd3. campylobacter coli lipopolysaccharide (lps) was extracted and analyzed by elisa, immunoblot binding and blocking studies, and found to avidly bind cholera toxin and peanut agglutinin. the lps from the patient's isolate also induced anti-ga1 antibodies in a rat ...200010734265
the gale gene of campylobacter jejuni is involved in lipopolysaccharide synthesis and virulence.lipopolysaccharide (lps) is one of the main virulence factors of gram-negative bacteria. the lps from campylobacter spp. has endotoxic properties and has been shown to play a role in adhesion. we previously cloned a gene cluster (wla) which is involved in the synthesis of the campylobacter jejuni 81116 lps molecule. sequence alignment of the first gene in this cluster indicated similarity with gale genes. these genes encode a udp-glucose 4-epimerase, which catalyzes the interconversion of udp-ga ...200010768949
immobilization with metal hydroxides as a means to concentrate food-borne bacteria for detection by cultural and molecular methods.the application of nucleic acid amplification methods to the detection of food-borne pathogens could be facilitated by concentrating the organisms from the food matrix before detection. this study evaluated the utility of metal hydroxide immobilization for the concentration of bacterial cells from dairy foods prior to detection by cultural and molecular methods. using reconstituted nonfat dry milk (nfdm) as a model, two food-borne pathogens (listeria monocytogenes and salmonella enterica serovar ...200010788338
helicobacter mesocricetorum sp. nov., a novel helicobacter isolated from the feces of syrian hamsters.a spiral-shaped bacterium with bipolar, single, nonsheathed flagella was isolated from the feces of syrian hamsters. the bacterium grew as a thin spreading film at 37 degrees c under microaerobic conditions, did not hydrolyze urea, was positive for catalase and alkaline phosphatase, reduced nitrate to nitrite, did not hydrolyze hippurate, and was sensitive to nalidixic acid but resistant to cephalothin. sequence analysis of the 16s rrna gene and biochemical and phenotypic criteria indicate that ...200010790105
molecular characterization of campylobacter jejuni from patients with guillain-barré and miller fisher syndromes.campylobacter jejuni has been identified as the predominant cause of antecedent infection in guillain-barré syndrome (gbs) and miller fisher syndrome (mfs). the risk of developing gbs or mfs may be higher after infection with specific c. jejuni types. to investigate the putative clonality, 18 gbs- or mfs-related c. jejuni strains from the netherlands and belgium and 17 control strains were analyzed by serotyping (penner and lior), restriction fragment length polymorphism analysis of pcr products ...200010834992
[campylobacter coli-related meningitis in an adult male]. 200010846879
campylobacter contamination of raw meat and poultry at retail sale: identification of multiple types and comparison with isolates from human infection.campylobacter species are the major cause of acute bacterial enteritis reported in the united kingdom, nonetheless many aspects of campylobacteriosis epidemiology remain poorly understood. the aim of this study was to determine the prevalence of campylobacter jejuni and campylobacter coli in fresh bovine, ovine, and porcine liver and chicken portions from retail outlets and compare strain subtype distributions with those associated with cases of human campylobacteriosis occurring within the same ...200011131886
molecular characterization of two-component systems of helicobacter pylori.two-component systems are frequently involved in the adaptation of bacteria to changing environmental conditions at the level of transcriptional regulation. here we report the characterization of members of the two-component systems of the gastric pathogen helicobacter pylori deduced from the genome sequence of strain 26695. we demonstrate that the response regulators hp166, hp1043, and hp1021 have essential functions, as disruption of the corresponding genes is lethal for the bacteria, irrespec ...200010735847
identification of campylobacter jejuni, c. coli, c. lari, c. upsaliensis, arcobacter butzleri, and a. butzleri-like species based on the glya gene.currently, the detection and identification of campylobacter and arcobacter species remains arduous, largely due to cross-species phenotypic similarities and a relatively narrow spectrum of biochemical reactivity. we have developed a pcr-hybridization strategy, wherein degenerate primers are used to amplify glya fragments from samples, which are then subjected to species-specific oligodeoxyribonucleotide probe hybridizations, to identify and distinguish between campylobacter jejuni, c. coli, c. ...200010747131
restriction fragment length polymorphism analysis using random chromosomal gene probes for epidemiological analysis of campylobacter jejuni infections.we have evaluated the ability of a new genotyping method for campylobacter jejuni based on restriction fragment length polymorphisms using random chromosomal gene probes. dnas from c. jejuni strains digested with each of three restriction enzymes, hhai, haeiii, and hpaii, were analyzed by southern hybridization using each of two unrelated cosmid clones, p14 and p15 (respectively containing 30- and 35-kb genomic dna fragments of c. jejuni strain oh4384). the method reported provides a stable and ...200010747164
a field-suitable, semisolid aerobic enrichment medium for isolation of campylobacter jejuni in small numbers.the objective of this study was to produce an economical, easy to prepare, field-suitable enrichment medium for detection of campylobacter jejuni in small numbers. a semisolid aerobic enrichment medium was developed. rates of recovery from inoculated medium, sterile swabs, and mixed cultures of c. jejuni and coliform bacteria were tested.200010747165
antibiotic resistance trends in enteropathogenic bacteria isolated in 1985-1987 and 1995-1998 in barcelona.trends in resistance to antimicrobial agents used for therapy have been evaluated with 3,797 enteropathogenic bacteria, campylobacter, salmonella, shigella, and yersinia, between 1985-1987 and 1995-1998. the greater increase in the rate of resistance was observed in campylobacter jejuni for quinolones (from 1 to 82%) and tetracycline (from 23 to 72%) and in gastroenteric salmonellae for ampicillin (from 8 to 44%), chloramphenicol (from 1.7 to 26%), and trimethoprim-sulfamethoxazole and nalidixic ...200010770742
rapid and specific enzyme immunoassay on hydrophobic grid membrane filter for detection and enumeration of thermophilic campylobacter spp. from milk and chicken rinses.six commercially available anti-campylobacter antibodies were examined for their applicability in an enzyme immunoassay on hydrophobic grid membrane filters, both for the detection and enumeration of campylobacter spp. when a panel of nine campylobacter (seven campylobacter jejuni and two campylobacter coli) and eight non-campylobacter strains were used in a dot-blot format enzyme immunoassay to test the specificity of these antibodies, only one polyclonal antibody (biodesign) detected all campy ...200010772214
fecal shedding of campylobacter and arcobacter spp. in dairy cattle.campylobacter jejuni, campylobacter coli, and arcobacter spp. were detected in feces of healthy dairy cows by highly specific multiplex-pcr assays. for c. jejuni, at this one-time sampling, cows from 80.6% of farm operations (n = 31) and 37.7% of individual dairy cattle fecal samples (n = 2,085) were positive. farm management factors were correlated with prevalence in herds in which >25% of cows were positive for c. jejuni. statistical significance was set at a p of 0.20. using these criteria, a ...200010788372
computer-assisted analysis and epidemiological value of genotyping methods for campylobacter jejuni and campylobacter coli.for epidemiological tracing of the thermotolerant campylobacter species c. jejuni and c. coli, reliable and highly discriminatory typing techniques are necessary. in this study the genotyping techniques of flagellin typing (flaa typing), pulsed-field gel electrophoresis (pfge), automated ribotyping, and amplified fragment length polymorphism (aflp) fingerprinting were compared. the following aspects were compared: computer-assisted analysis, discriminatory power, and use for epidemiological typi ...200010790125
intercellular communication in helicobacter pylori: luxs is essential for the production of an extracellular signaling molecule.individual bacteria of numerous species can communicate and coordinate their actions via the production, release, and detection of extracellular signaling molecules. in this study, we used the vibrio harveyi luminescence bioassay to determine whether helicobacter pylori produces such a factor. cell-free conditioned media from h. pylori strains 60190 and 26695 each induced >100-fold-greater luminescence in v. harveyi than did sterile culture medium. the h. pylori signaling molecule had a molecula ...200010816463
amplified fragment length polymorphism analysis of campylobacter jejuni strains isolated from chickens and from patients with gastroenteritis or guillain-barré or miller fisher syndrome.the high-resolution genotyping method of amplified fragment length polymorphism (aflp) analysis was used to study the genetic relationships between campylobacter jejuni strains infecting chickens (n = 54) and those causing gastroenteritis in humans (n = 53). in addition, c. jejuni strains associated with the development of guillain-barré syndrome (gbs) (n = 14) and miller fisher syndrome (mfs) (n = 4), two related acute paralytic syndromes in human, were included. strains were isolated between 1 ...200010966409
application of the 5'-nuclease pcr assay in evaluation and development of methods for quantitative detection of campylobacter jejuni.campylobacter jejuni is recognized as a leading human food-borne pathogen. traditional diagnostic testing for c. jejuni is not reliable due to special growth requirements and the possibility that this bacterium can enter a viable but nonculturable state. nucleic acid-based tests have emerged as a useful alternative to traditional enrichment testing. in this article, we present a 5'-nuclease pcr assay for quantitative detection of c. jejuni and describe its evaluation. a probe including positions ...200010966425
quantitative immunocapture pcr assay for detection of campylobacter jejuni in foods.the rapid detection of food-borne bacterial pathogens as part of a quality control program is necessary for the maintenance of a safe food supply. in this report, we present our findings for an immunocapture pcr method for the detection of campylobacter jejuni in foods. the method permits direct detection of the pathogen without an enrichment step and can be performed in approximately 8 h. assay results are quantitative, and one cell in a milliliter sample can be detected. application of the met ...200010966437
phenotypic and genotypic diversity of the flagellin gene (flic) among clostridium difficile isolates from different serogroups.phenotypic and genotypic diversity of the flagellin gene (flic) of clostridium difficile was studied in 47 isolates from various origins belonging to the serogroups a, b, c, d, f, g, h, i, k, x, and s3. electron microscopy revealed 17 nonflagellated strains and 30 flagellated strains. pcr and reverse transcription-pcr demonstrated that the flagellin gene was present in all strains and that the flic gene was expressed in both flagellated and nonflagellated strains. southern blotting showed the pr ...200010970353
cytolethal distending toxin sequence and activity in the enterohepatic pathogen helicobacter hepaticus.little is known about the molecular pathogenesis of hepatitis and enterocolitis caused by enterohepatic helicobacter species. sonicates of the murine pathogen helicobacter hepaticus were found to cause progressive cell distension, accumulation of filamentous actin, and g(2)/m cell cycle arrest in hela cell monolayers. the genes encoding this cytotoxic activity were cloned from h. hepaticus. three open reading frames with closest homology to cdta, cdtb, and cdtc from campylobacter jejuni were ide ...200010603386
localized reversible frameshift mutation in the flha gene confers phase variability to flagellin gene expression in campylobacter coli.phase variation of flagellin gene expression in campylobacter coli ua585 was correlated with high-frequency, reversible insertion and deletion frameshift mutations in a short homopolymeric tract of thymine residues located in the n-terminal coding region of the flha gene. mutation-based phase variation in flha may generate functional diversity in the host and environment.200010613882
prevalence of campylobacter, arcobacter, helicobacter, and sutterella spp. in human fecal samples as estimated by a reevaluation of isolation methods for campylobacters.the aims of this study were to investigate the prevalence of campylobacteria including campylobacter jejuni subsp. jejuni (c. jejuni) and campylobacter coli in human clinical samples and in samples from healthy individuals and to reevaluate the efficacies of conventional selective methods for isolation of campylobacter spp. two charcoal-based selective media, modified charcoal cefoperazone deoxycholate agar (mccda) and cefoperazone-amphotericin-teicoplanin (cat) agar, were compared with skirrow' ...200010618103
efficient isolation of campylobacteria from stools. 200010979752
genotyping of campylobacter spp. 200010618195
isolation and characterization of campylobacter jejuni subsp. jejuni from macaroni penguins (eudyptes chrysolophus) in the subantarctic region.on bird island, south georgia, albatrosses (n = 140), penguins (n = 100), and fur seals (n = 206) were sampled for campylobacter jejuni. c. jejuni subsp. jejuni was recovered from three macaroni penguins (eudyptes chrysolophus). these isolates, the first reported for the subantarctic region, showed low genetic diversity and high similarity to northern hemisphere c. jejuni isolates, possibly suggesting recent introduction to the area.200010618265
sequence polymorphism, predicted secondary structures, and surface-exposed conformational epitopes of campylobacter major outer membrane protein.the major outer membrane protein (momp), a putative porin and a multifunction surface protein of campylobacter jejuni, may play an important role in the adaptation of the organism to various host environments. to begin to dissect the biological functions and antigenic features of this protein, the gene (designated cmp) encoding momp was identified and characterized from 22 strains of c. jejuni and one strain of c. coli. it was shown that the single-copy cmp locus encoded a protein with character ...200010992471
characterization and expression of hmur, a tonb-dependent hemoglobin receptor of porphyromonas gingivalis.the gram-negative pathogen porphyromonas gingivalis requires hemin for growth. hemoglobin bound to haptoglobin and hemin complexed to hemopexin can be used as heme sources, indicating that p. gingivalis must have a means to remove the hemin from these host iron-binding proteins. however, the specific mechanisms utilized by p. gingivalis for the extraction of heme from heme-binding proteins and for iron transport are poorly understood. in this study we have determined that a newly identified tonb ...200011004172
antibodies, directed towards campylobacter jejuni antigens, in sera from poultry abattoir workers.occupational exposure of susceptible humans to campylobacter jejuni appears to result in resistance to disease. this is believed to be due to acquired protective immunity. to support this hypothesis the levels of c. jejuni-specific igg and igm antibodies were determined in sera from poultry abattoir workers. such individuals are persistently exposed to c. jejuni, but apparently rarely acquire campylobacteriosis. sera from 43 short-term workers (employed < or = 1 month), 78 long-term workers and ...200011012618
virulent strains of helicobacter pylori demonstrate delayed phagocytosis and stimulate homotypic phagosome fusion in macrophages.helicobacter pylori colonizes the gastric epithelium of approximately 50% of the world's population and plays a causative role in the development of gastric and duodenal ulcers. h. pylori is phagocytosed by mononuclear phagocytes, but the internalized bacteria are not killed and the reasons for this host defense defect are unclear. we now show using immunofluorescence and electron microscopy that h. pylori employs an unusual mechanism to avoid phagocytic killing: delayed entry followed by homoty ...200010620610
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