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campylobacter dna is present in circulating myelomonocytic cells of healthy persons and in persons with guillain-barré syndrome.campylobacter jejuni is the prime cause of foodborne bacterial gastroenteritis. an important complication of c. jejuni enteritis is guillain-barré syndrome (gbs), an immune-mediated disorder of the peripheral nerve. the presence of c. jejuni dna in peripheral blood mononuclear cells (pbmc) of patients with gbs, patients with c. jejuni enteritis, and healthy subjects was studied. two target genes, the flagellin and the ceue genes, were used for polymerase chain reaction (pcr) identification of ca ...200211807702
prevalence and comparison of genetic profiles of campylobacter strains isolated from poultry and sporadic cases of campylobacteriosis in humans.between july 1998 and june 1999, 93 lots of broiler chickens distributed on 57 farms were sampled in two abattoirs of the province of quebec (canada). a total of 2,325 samples of cecal material were analyzed to determine the prevalence of campylobacters. biotyping and pulsed-field gel electrophoresis (pfge) were done on 20% of the campylobacter isolates to study the distribution within poultry production. macrorestriction profiles were compared with profiles of 24 campylobacter strains isolated ...200211808809
identification and molecular characterisation of cmeb, a campylobacter jejuni multidrug efflux pump.a multidrug efflux pump gene (cmeb) was identified from the published campylobacter jejuni genome sequence. secondary structural analysis showed that the gene encoded a protein belonging to the resistance nodulation cell division (rnd) family of efflux transporters. the gene was inactivated by insertional mutagenesis. compared with the wild-type strain (nctc 11168), the resultant knockout strain (nctc 11168-cmeb::kan(r)) displayed increased susceptibility to a range of antibiotics including beta ...200211814661
effect of cold starvation, acid stress, and nutrients on metabolic activity of helicobacter pylori.helicobacter pylori can transform, in vivo as well as in vitro, from dividing spiral-shaped forms into nonculturable coccoids, with intermediate forms called u forms. the importance of nonculturable coccoid forms of h. pylori in disease transmission and antibiotic treatment failures is unclear. metabolic activities of actively growing as well as nonculturable h. pylori were investigated by comparing the concentrations of cellular atp and total rna, gene expression, presence of cytoplasmic polyph ...200211772603
16s rrna-based analysis of microbiota from the cecum of broiler chickens.the microbiota of the intestinal tract of chickens plays an important role in inhibiting the establishment of intestinal pathogens. earlier culturing and microscopic examinations indicated that only a fraction of the bacteria in the cecum of chickens could be grown in the laboratory. therefore, a survey of cecal bacteria was done by retrieval of 16s rrna gene sequences from dna isolated from the cecal content and the cecal mucosa. the ribosomal gene sequences were amplified with universal primer ...200211772618
occurrence of cryptosporidium and giardia in wild ducks along the rio grande river valley in southern new mexico.fecal samples were taken from wild ducks on the lower rio grande river around las cruces, n. mex., from september 2000 to january 2001. giardia cysts and cryptosporidium oocysts were purified from 69 samples by sucrose enrichment followed by cesium chloride (cscl) gradient centrifugation and were viewed via fluorescent-antibody (fa) staining. for some samples, recovered cysts and oocysts were further screened via pcr to determine the presence of giardia lamblia and crytosporidium parvum. the res ...200211772622
multiplex lightcycler pcr assay for detection and differentiation of bordetella pertussis and bordetella parapertussis in nasopharyngeal specimens.a rapid real-time multiplex pcr assay for detecting and differentiating bordetella pertussis and bordetella parapertussis in nasopharyngeal swabs was developed. this assay (lc-pcr-is) targets the insertion sequences is481 and is1001 of b. pertussis and b. parapertussis, respectively, and is performed using the lightcycler (roche molecular biochemicals, indianapolis, ind.). the analytical sensitivity is less than one organism per reaction. results for bordetella culture and/or direct fluorescent ...200211773099
evaluation of a novel heminested pcr assay based on the phosphoglucosamine mutase gene for detection of helicobacter pylori in saliva and dental plaque.a novel heminested pcr protocol was developed for the specific detection of helicobacter pylori at low copy numbers. a set of primers specific for the phosphoglucosamine mutase gene (glmm) of h. pylori produced a 765-bp fragment that was used as template for the heminested primer pair delineating a 496-bp fragment. by using agarose gel electrophoresis for detection of the heminested pcr-amplified products, amplification of h. pylori genomic dna was achieved at concentrations as low as 0.1 pg, eq ...200211773117
small-fragment genomic libraries for the display of putative epitopes from clinically significant pathogens.taking advantage of whole genome sequences of bacterial pathogens in many thriving diseases with global impact, we developed a comprehensive screening procedure for the identification of putative vaccine candidate antigens. importantly, this procedure relies on highly representative small-fragment genomic libraries that are expressed to display frame-selected epitope-size peptides on a bacterial cell surface and to interact directly with carefully selected disease-relevant high-titer sera. here ...200312866421
characterization of a new lexa binding motif in the marine magnetotactic bacterium strain mc-1.mc-1 is a marine, magnetotactic bacterium that is phylogenetically associated with the alpha subclass of the proteobacteria and is the first and only magnetotactic coccus isolated in pure culture to date. by using a tblastn search, a lexa gene was identified in the published genome of mc-1; it was subsequently cloned, and the protein was purified to >90% purity. results from reverse transcription-pcr analysis revealed that the mc-1 lexa gene comprises a single transcriptional unit with two open ...200312867456
myocarditis related to campylobacter jejuni infection: a case report.myocarditis can develop as a complication of various infections and is most commonly linked to enterovirus infections. myocarditis is rarely associated with bacterial infections; salmonellosis and shigellosis have been the most frequently reported bacterial cause. we report a case of myocarditis related to campylobacter jejuni enteritis.200312869210
growth of autobioluminescent campylobacter jejuni in response to various environmental conditions.an autobioluminescent campylobacter jejuni organism generated from the fusion of luxcdabe genes from xenorhabdus luminescens to the flaa promoter of c. jejuni was used in conjunction with gel-stabilized gradient plates to map the responses of this organism to three environmental factors (ph, nacl concentration, and temperature) and various concentrations of l-fucose, d-fucose, and sodium desoxycholate. the minimum, optimum, and maximum temperatures for the growth of autobioluminescent c. jejuni ...200312870752
a point of view: the need to identify an antigen in psyconeuroimmunological disorders.several lines of evidence support a mutual relationship between the nervous system and the immune system. therefore, it is not surprising that some neuropsychiatric disorders are also characterized by immune abnormalities. in patients with phobic disorders and in patients with migraine without aura some common immune abnormalities have been detected and, in particular, natural immunity deficits, exaggerated release of proinflammatory cytokines and circulating bacterial endotoxins have been found ...200312871180
axonal pharyngeal-cervical-brachial variant of guillain-barré syndrome without anti-gt1a igg antibody.we report two cases of pharyngeal-cervical-brachial (pcb) variant of guillain-barré syndrome (gbs). the patients developed dysphagia and weakness of the neck and arms subsequent to campylobacter jejuni infection. oropharyngeal palsy recovered poorly. electrophysiological findings demonstrated axonal conduction failure. anti-gd1a immunoglobulin g (igg) antibody was detected in one case, and anti-gm1b igg antibody in another. anti-gt1a igg and immunoglobulin m (igm) antibodies were negative in bot ...200312872333
[antibody response following campylobacter infections determined by elisa].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. 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 determine the cut-off for negative results. with 90 percentile specificity, igg, igm, and iga showed a sensitivity of 71, 60, and 80%, respe ...200312872469
[campylobacter jejuni enteritis and guillain-barre syndrome]. 200312872690
induction of conduction block by campylobacter jejuni lipopolysaccharides and focal neural insult.a systemic exposure to gram negative lps have caused transient conduction abnormalities in a certain strain of rats probably associated with the action of cytokines secreted by macrophages. our previous studies demonstrated that anti-gm1 antibodies induced in rats by the cross-reactive cj-lps, caused no conduction abnormalities. we designed the present study to evaluate the effect of systemic exposure to cj-lps on nerve conduction after a focal minor neural trauma. female lewis rats were sensiti ...200312873748
association of anti-gm1 antibodies but not of anti-cytomegalovirus, campylobacter jejuni and helicobacter pylori igg, with a poor outcome in guillain-barré syndrome.few reports exist on the influence of humoral immune responses, against microorganisms involved in infections preceding guillain-barré syndrome (gbs) and gm1, on clinical outcome. nor is there any data on the relation between anti-helicobacter pylori antibodies and prognosis in patients with gbs. to address these questions, we assayed and correlated serum anti-gm1 igg and igm and anti-h. pylori, anti-campylobacter jejuni and anti-cytomegalovirus (cmv) igg with duration of hospitalization of gbs ...200312873755
critical role of multidrug efflux pump cmeabc in bile resistance and in vivo colonization of campylobacter jejuni.cmeabc functions as a multidrug efflux pump contributing to the resistance of campylobacter to a broad range of antimicrobials. in this study, we examined the role of cmeabc in bile resistance and its contribution to the adaptation of campylobacter jejuni in the intestinal tract of the chicken, a natural host and a major reservoir for campylobacter. inactivation of cmeabc drastically decreased the resistance of campylobacter to various bile salts. addition of choleate (2 mm) in culture medium im ...200312874300
characterization of the novel factor paa involved in the early steps of the adhesion mechanism of attaching and effacing escherichia coli.nonenterotoxigenic porcine escherichia coli strains belonging to the serogroup o45 have been associated with postweaning diarrhea in swine and adhere to intestinal epithelial cells in a characteristic attaching and effacing (a/e) pattern. o45 porcine enteropathogenic e. coli (pepec) strain 86-1390 induces typical a/e lesions in a pig ileal explant model. using tnphoa transposon insertion mutagenesis on strain 86-1390, we found a mutant that did not induce a/e lesions. the insertion was identifie ...200312874331
survival of foodborne pathogens on stainless steel surfaces and cross-contamination to foods.the retention of bacteria on food contact surfaces increases the risk of cross-contamination of these microorganisms to food. the risk has been considered to be lowered when the surfaces are dry, partly because bacterial growth and survival would be reduced. however, some non-spore-forming bacteria might be able to withstand dry conditions on surfaces for an extensive period of time. in this study the survival of salmonella enteritidis, staphylococcus aureus and campylobacter jejuni on stainless ...200312878381
antimicrobial resistance of bacterial pathogens associated with diarrheal patients in indonesia.the antimicrobial susceptibility patterns for 2,812 bacterial pathogens isolated from diarrheal patients admitted to hospitals in several provinces in the cities of jakarta, padang, medan, denpasar, pontianak, makassar, and batam, indonesia were analyzed from 1995 to 2001 to determine their changing trends in response to eight antibiotics: ampicillin, trimethoprim-sulfamethoxazole, chloramphenicol, tetracycline, cephalothin, ceftriaxone, norfloxacin, and ciprofloxacin. vibrio cholerae o1 (37.1%) ...200312887025
effects of diet formulations containing proteins from different sources on intestinal colonization by campylobacter jejuni in broiler chickens.the objective of this study was to compare the effects of 3 diet formulations containing different protein sources (animal, plant, and a combination of animal and plant) on the colonization of campylobacter jejuni in the gastrointestinal tract of broiler chickens. a freshly isolated strain of c. jejuni (biotype iv, serotype hs o:21, o:29, hl untypable) from a broiler chicken was used to infect 3-day-old chicks that had been free of c. jejuni; 0.5 ml of an inoculum containing 10(8) colony-forming ...200312889727
[polyradiculoneuritis and campylobacter jejuni: clinical and physiopathological aspects].several explanations have been proposed to explain the relationship between axonal forms of acute auto-immune inflammatory polyradiculoneuritis and campylobacter jejuni. the major hypothesis involving molecular imitation is based on the existence of common antigenic determinants (epitopes) in the lipopolysaccharides of the infectious agent and gangliosides, i.e. glycosphingolipides on the surface of the nervous system cells, especially peripheral nervous system cells. the purpose of this literat ...200312891754
diverse effects of ascorbic acid and palmitoyl ascorbate on helicobacter pylori survival and growth.among many antioxidants used in the food, pharmaceutical and cosmetic industries, ascorbic acid (aa) is one of the most important. aa has been suggested to decrease the risk of gastric disease (gastritis, duodenal ulcer, and carcinoma) by direct action on helicobacter pylori. however, there are limited studies on the possible role of aa and its derivatives such as palmitoyl ascorbate (pa) on the growth and survival of h. pylori. in the present study it was demonstrated in vitro that aa in the co ...200312892889
sources of campylobacter colonization in broiler chickens. 200312902214
isolation and characterization of campylobacter bacteriophages from retail poultry.the ability of phages to survive processing is an important aspect of their potential use in the biocontrol of campylobacter in poultry production. to this end, we have developed a procedure to recover campylobacter bacteriophages from chilled and frozen retail poultry and have validated the sensitivity of the method by using a characterized campylobacter phage (i.e., nctc 12674). by using this method, we have shown that campylobacter phages can survive on retail chicken under commercial storage ...200312902236
effect of incubation temperature on isolation of campylobacter jejuni genotypes from foodstuffs enriched in preston broth.preston broth and agar incubated at either 37 or 42 degrees c have been widely used to isolate campylobacters from foodstuffs. the consequences of using either incubation temperature were investigated. retail packs of raw chicken (n = 24) and raw lamb liver (n = 30) were purchased. samples were incubated in preston broth at 37 and 42 degrees c and then streaked onto preston agar and incubated as before. two campylobacter isolates per treatment were characterized. poultry isolates were genotyped ...200312902254
colonization of arabidopsis thaliana with salmonella enterica and enterohemorrhagic escherichia coli o157:h7 and competition by enterobacter asburiae.enteric pathogens, such as salmonella enterica and escherichia coli o157:h7, have been shown to contaminate fresh produce. under appropriate conditions, these bacteria will grow on and invade the plant tissue. we have developed arabidopsis thaliana (thale cress) as a model system with the intention of studying plant responses to human pathogens. under sterile conditions and at 100% humidity, s. enterica serovar newport and e. coli o157:h7 grew to 10(9) cfu g(-1) on a. thaliana roots and to 2 x 1 ...200312902287
description of a "phoenix" phenomenon in the growth of campylobacter jejuni at temperatures close to the minimum for growth.when campylobacter jejuni cultures that had been grown in broth at 39 degrees c were subcultured into fresh medium at 30 degrees c, there was a transient period of growth followed by a decline in viable-cell numbers before growth resumed once more. we propose that this complex behavior is the net effect of the growth of inoculum cells followed by a loss of viability due to oxidative stress and the subsequent emergence of a spontaneously arising mutant population that takes over the culture.200312902294
reduction of experimental salmonella and campylobacter contamination of chicken skin by application of lytic bacteriophages.lytic bacteriophages, applied to chicken skin that had been experimentally contaminated with salmonella enterica serovar enteritidis or campylobacter jejuni at a multiplicity of infection (moi) of 1, increased in titer and reduced the pathogen numbers by less than 1 log(10) unit. phages applied at a moi of 100 to 1,000 rapidly reduced the recoverable bacterial numbers by up to 2 log(10) units over 48 h. when the level of salmonella contamination was low (< log(10) 2 per unit area of skin) and th ...200312902308
detection of clarithromycin-resistant helicobacter pylori in stool samples.the recognition of the role of helicobacter pylori in gastric diseases has led to the widespread use of antibiotics in the eradication of this pathogen. the most advocated therapy, triple therapy, often includes clarithromycin. it is well known that clarithromycin resistance is one of the major causes of eradication failure. the development of a rapid noninvasive technique that could easily be performed on fecal samples and that could also provide information about the antibiotic resistance of t ...200312904368
differences in gene content among salmonella enterica serovar typhi isolates.we used a nonredundant microarray of the salmonella enterica serovar typhimurium lt2 and typhi ct18 genomes to assess the genomic content of a diverse set of isolates of serovar typhi. comparative genomic hybridization revealed 13 regions of absent or divergent gene content in the eight typhi strains examined compared to typhi ct18. in particular, two typhi ct18 prophage regions, sty1048 to sty1077 and sty2038 to sty2077, as well as a five-gene islet (sty3188 to sty3193) were absent or divergent ...200312904395
molecular typing of campylobacter jejuni isolates involved in a neonatal outbreak indicates nosocomial transmission.genotypic typing by restriction fragment length polymorphism and pulsed-field gel electrophoresis showed that two neonates in a neonatal ward were infected with the same campylobacter jejuni strain. isolates from the mother and brother of the index patient were identical to each other but distinct from the neonatal type. genotyping results therefore suggested that the neonatal c. jejuni infection was nosocomial in origin.200312904420
role of microfilaments and microtubules in the invasion of int-407 cells by campylobacter jejuni.the internalization mechanisms triggered by campylobacter jejuni were studied by invasion assays conducted with different inhibitors that act on the cytoskeleton structure of eukaryotic cells. the depolymerization of microfilaments by cytochalasin-d and that of microtubules by colchicines and nocodazole inhibited the uptake of c. jejuni into int-407 cells in a dose-dependent manner. the inhibitory effect of microfilament depolymerization on c. jejuni internalization was more pronounced than that ...200312906108
restriction site tagged (rst) microarrays: a novel technique to study the species composition of complex microbial systems.we have developed a new type of microarray, restriction site tagged (rst), for example noti, microarrays. in this approach only sequences surrounding specific restriction sites (i.e. noti linking clones) were used for generating microarrays. dna was labeled using a new procedure, noti representation, where only sequences surrounding noti sites were labeled. due to these modifications, the sensitivity of rst microarrays increases several hundred-fold compared to that of ordinary genomic microarra ...200312907747
prevalence of multiple antibiotic resistance in 443 campylobacter spp. isolated from humans and animals.in view of recent findings that a multidrug efflux pump cmeabc exists in campylobacter jejuni, 391 c. jejuni and 52 campylobacter coli of human and animal origin were examined for a multidrug resistance phenotype.200312917241
effect of fermented feed on the susceptibility for campylobacter jejuni colonisation in broiler chickens with and without concurrent inoculation of salmonella enteritidis.fermented liquid feed (flf) protects broiler chickens against colonisation with salmonella. while campylobacter causes more disease cases in humans than salmonella, the effect of flf on campylobacter was assessed. the fermented liquid feed is a moistened feed with a high number of lactobacilli, a high concentration of lactic acid, and a ph of 4. in three experiments campylobacter was orally applied to individually housed 9-day-old broiler chickens. a significant reduction of susceptibility, as d ...200312927709
rapid detection of campylobacter jejuni in chicken rinse water by melting-peak analysis of amplicons in real-time polymerase chain reaction.five dna extraction protocols for the detection of campylobacter spp. by polymerase chain reaction (pcr) were compared. a method involving triton x-100 produced template dna of sufficient quality to allow the detection of campylobacter jejuni at levels of 100 cfu/ml in pure culture. primers were designed on the basis of the cadf gene sequence. with a sybr green i real-time pcr assay, these primers amplified only sequences present in c. jejuni to produce a product with a melting temperature of 81 ...200312929818
sequence analysis of a cryptic plasmid pcj419 from campylobacter jejuni and construction of an escherichia coli-campylobacter shuttle vector.a small cryptic plasmid, pcj419, was identified in a human clinical isolate of campylobacter jejuni, cloned and sequenced. pcj419 is a circular molecule of 4013 bp with a g+c content of 27.1%. the products of four open reading frames (orfs) share significant sequence similarity with putative proteins from known c. jejuni and campylobacter coli plasmids. orf-1 encodes a putative mobilisation protein (mob). orf-2 and orf-3 encode proteins that have high identity to putative repa and repb proteins, ...200312932741
interactions of campylobacter jejuni cytolethal distending toxin subunits cdta and cdtc with hela cells.campylobacter jejuni produces a toxin, called cytolethal distending toxin (cdt), which causes direct dna damage leading to invocation of dna damage checkpoint pathways. the affected cells arrest in g(1) or g(2) and eventually die. cdt consists of three protein subunits, cdta, cdtb, and cdtc, with cdtb recently identified as a nuclease. however, little is known about the functions of cdta or cdtc. in this work, enzyme-linked immunosorbent assay-based experiments were used to show, for the first t ...200312933829
in vitro activities of new fluoroquinolones against campylobacter jejuni and campylobacter coli isolates obtained from humans in 1980 to 1982 and 1997 to 2001.the antibacterial activities of three newly developed fluoroquinolones (gatifloxacin, levofloxacin, and moxifloxacin) against a total of 307 gastrointestinal human isolates of campylobacter jejuni and campylobacter coli collected during 1980 to 1982 and 1997 to 2001 were examined and compared to those of ciprofloxacin and the unrelated antibacterial agents, clarithromycin, erythromycin, and tetracycline by using the agar plate dilution method. all of the fluoroquinolones exhibited a good activit ...200312936999
development of a triplex pcr assay for the specific detection of campylobacter jejuni, salmonella spp., and escherichia coli o157:h7.a triplex pcr assay was developed and evaluated for efficacy in detecting campylobacter jejuni, salmonella spp., and escherichia coli o157:h7 in a variety of raw and ready-to-eat food products. following a short enrichment period, artificially contaminated food samples were subjected to a triplex pcr assay, which incorporated published primers for each food pathogen, a protocol for sample collection, and a pcr procedure designed specifically for the assay. the selected primers amplified fragment ...200312944114
development of a sensitive dna microarray suitable for rapid detection of campylobacter spp.campylobacter is the most common cause of human acute bacterial gastroenteritis worldwide, widely distributed and isolated from human clinical samples as well as from many other different sources. to comply with the demands of consumers for food safety, there is a need for development of a rapid, sensitive and specific detection method for campylobacter. in this study, we present the development of a novel sensitive dna-microarray based detection method, evaluated on campylobacter and non-campyl ...200312944122
natural transformation of campylobacter jejuni requires components of a type ii secretion system.the human pathogen campylobacter jejuni is one of more than 40 naturally competent bacterial species able to import macromolecular dna from the environment and incorporate it into their genomes. however, in c. jejuni little is known about the genes involved in this process. we used random transposon mutagenesis to identify genes that are required for the transformation of this organism. we isolated mutants with insertions in 11 different genes; most of the mutants are affected in the dna uptake ...200312949093
rapid selection of quinolone resistance in campylobacter jejuni but not in escherichia coli in individually housed broilers.to determine the within-host population dynamics of campylobacter jejuni and escherichia coli in chickens during and after treatment with fluoroquinolones.200312951353
evolution of mosaic operons by horizontal gene transfer and gene displacement in situ.shuffling and disruption of operons and horizontal gene transfer are major contributions to the new, dynamic view of prokaryotic evolution. under the 'selfish operon' hypothesis, operons are viewed as mobile genetic entities that are constantly disseminated via horizontal gene transfer, although their retention could be favored by the advantage of coregulation of functionally linked genes. here we apply comparative genomics and phylogenetic analysis to examine horizontal transfer of entire opero ...200312952534
application of dna microarrays to study the evolutionary genomics of yersinia pestis and yersinia pseudotuberculosis.yersinia pestis, the causative agent of plague, diverged from yersinia pseudotuberculosis, an enteric pathogen, an estimated 1500-20,000 years ago. genetic characterization of these closely related organisms represents a useful model to study the rapid emergence of bacterial pathogens that threaten mankind. to this end, we undertook genome-wide dna microarray analysis of 22 strains of y. pestis and 10 strains of y. pseudotuberculosis of diverse origin. eleven y. pestis dna loci were deemed absen ...200312952873
the low complexity proteins from enteric pathogenic bacteria: taxonomic parallels embedded in diversity.the number and functions of the low complexity (lc) proteins from four enteric bacterial pathogens escherichia coli o157, vibrio cholerae, helicobacter pylori and campylobacter jejuni were compared. for this purpose the lc proteins were grouped into 3 categories for pairwise comparisons. these were common, variant and lc proteins with no homologues (lcnh). homologous lc proteins in both species in a given pairwise comparison were grouped as common. lc proteins of same function but not of low com ...200312954090
effect of campylobacter-specific maternal antibodies on campylobacter jejuni colonization in young chickens.using laboratory challenge experiments, we examined whether campylobacter-specific maternal antibody (mab) plays a protective role in young chickens, which are usually free of campylobacter under natural production conditions. kinetics of c. jejuni colonization were compared by infecting 3-day-old broiler chicks, which were naturally positive for campylobacter-specific mab, and 21-day-old broilers, which were negative for campylobacter-specific mab. the onset of colonization occurred much sooner ...200312957925
characterization of a theta-type plasmid from lactobacillus sakei: a potential basis for low-copy-number vectors in lactobacilli.the complete nucleotide sequence of the 13-kb plasmid prv500, isolated from lactobacillus sakei rv332, was determined. sequence analysis enabled the identification of genes coding for a putative type i restriction-modification system, two genes coding for putative recombinases of the integrase family, and a region likely involved in replication. the structural features of this region, comprising a putative ori segment containing 11- and 22-bp repeats and a repa gene coding for a putative initiat ...200312957947
toward an international standard for pcr-based detection of food-borne thermotolerant campylobacters: assay development and analytical validation.as part of a european research project (food-pcr), we developed a standardized and robust pcr detection assay specific for the three most frequently reported food-borne pathogenic campylobacter species, c. jejuni, c. coli, and c. lari. fifteen published and unpublished pcr primers targeting the 16s rrna gene were tested in all possible pairwise combinations, as well as two published primers targeting the 23s rrna gene. a panel of 150 strains including target and nontarget strains was used in an ...200312957958
toward an international standard for pcr-based detection of food-borne thermotolerant campylobacters: validation in a multicenter collaborative trial.as part of a european research project, the performance of a pcr assay to detect food-borne thermotolerant campylobacters (campylobacter jejuni, c. coli, and c. lari) was evaluated through an international collaborative trial involving 12 participating laboratories. dna from 10 target and 8 nontarget strains was tested, and the results were reported as the presence of a positive signal after gel electrophoresis. the overall inclusivity (sensitivity) was 93.7%, and the exclusivity (specificity) w ...200312957959
unexpected decrease with age of helicobacter pylori seroprevalence among swedish blood donors.blood donors are often used as proxies for the general population in studies of helicobacter pylori epidemiology. our aim was to test if the age-specific seroprevalence rates among blood donors match with the corresponding rates in a random population sample. this descriptive study was based on sera obtained from 3,502 blood donors representing all swedish counties and cities. an age-stratified random population sample of 1,030 from stockholm county served as comparison. sera were analyzed by an ...200312958222
clonal complexes of campylobacter jejuni identified by multilocus sequence typing correlate with strain associations identified by multilocus enzyme electrophoresis.multilocus sequence typing (mlst) and pulsed-field gel electrophoresis (pfge) with smai were used to subtype 55 isolates of campylobacter jejuni from a diverse range of human and animal sources previously characterized by multilocus enzyme electrophoresis (mee). mee and mlst targeted 11 and 7 loci, respectively, and all loci were unique to each method. mee, mlst, and pfge identified 40, 37, and 48 discrete subtypes, respectively, with many of the subtypes occurring only once within the data set. ...200312958226
microarray-based identification of thermophilic campylobacter jejuni, c. coli, c. lari, and c. upsaliensis.dna microarrays are an excellent potential tool for clinical microbiology, since this technology allows relatively rapid identification and characterization of microbial and viral pathogens. in the present study, an oligonucleotide microarray was developed and used for the analysis of thermophilic campylobacter spp., the primary food-borne pathogen in the united states. we analyzed four campylobacter species: campylobacter jejuni, c. coli, c. lari, and c. upsaliensis. our assay relies on the pcr ...200312958228
campylobacter-stimulated int407 cells produce dissociated cytokine profiles.to study the action of factors produced by living campylobacter jejuni (c. jejuni) against those present within sonicated and filtrated bacteria on induction of potential cytokines by the human intestinal cell line int407.200312963383
acute motor conduction block neuropathy another guillain-barré syndrome variant.to report two patients with an acute exclusively motor neuropathy with conduction blocks.200312963751
cdr3 spectratyping analysis of the t cell receptor repertoire in guillain-barré and fisher syndromes.several autoimmune and infectious disorders show oligoclonal expansion of particular t cell phenotypes. the extent of t cell involvement in the pathogenesis of guillain-barré syndrome (gbs), a post-infectious autoimmune neuropathy, however, is not clear. to identify the pathogenic t cell phenotypes in gbs and fisher syndrome (fs), variations in t cell receptor use of the v beta 1-24 and v delta 1-5 chain genes were analyzed at complementarity-determining region 3 level in 119 patients with gbs o ...200312965261
the genome of campylobacter jejuni: codon and amino acid usage.the genes from the genome of the at-rich bacterium campylobacter jejuni were analysed and characterised with respect to usage and amino acid usage. codon usage is generally biased for all amino acids having synonymous codons, so that at-rich synonyms are most frequently used. markov chain analysis showed that codon bias and over- or underrepresentation of the corresponding tri-letter words are not related. predicted secondary structure, lipophilicity, codon position within the gene, strand, and ...200312969016
identification of campylobacteria isolated from danish broilers by phenotypic tests and species-specific pcr assays.to validate a phenotypic campylobacter species identification method employed to identify campylobacters in broilers by comparison with campylobacterial species identification using various species-specific pcr analyses.200312969276
identification of a novel stress resistance mechanism in campylobacter jejuni.to study stress resistance mechanisms in campylobacter spp.200312969282
the cog database: an updated version includes eukaryotes.the availability of multiple, essentially complete genome sequences of prokaryotes and eukaryotes spurred both the demand and the opportunity for the construction of an evolutionary classification of genes from these genomes. such a classification system based on orthologous relationships between genes appears to be a natural framework for comparative genomics and should facilitate both functional annotation of genomes and large-scale evolutionary studies.200312969510
fulminant crohn's colitis after allogeneic stem cell transplantation.we report a case of fulminant crohn's colitis that occurred following non-myeloablative allogeneic stem cell transplantation for hodgkin's lymphoma. adoptive transfer of inflammatory bowel disease by haematopoietic cells is recognised in several animal models of inflammatory bowel disease and remission of crohn's disease has been reported in patients who have received a bone marrow transplant. however, adoptive transfer of crohn's disease susceptibility leading to phenotypic manifestation of the ...200312970148
[susceptibility of campylobacter jejuni clinical isolates from children to eight antibiotics].this study aimed to identify the activity of eight antibiotics (ofloxacin, moxifloxacin, azithromycin, erythromycin, clindamycin, ampicillin, amoxicillin-clavulanic acid and tetracycline) against 80 strains of campylobacter jejuni isolated from children. minimal inhibitory concentrations (mic) were determined by an agar dilution method. resistance to azithromycin and erythromycin was considered when mic > or =8 mg/l, to clindamycin when mic > or =1 mg/l, to amoxicillin-clavulanic acid and ampici ...200312973460
an improved probability mapping approach to assess genome mosaicism.maximum likelihood and posterior probability mapping are useful visualization techniques that are used to ascertain the mosaic nature of prokaryotic genomes. however, posterior probabilities, especially when calculated for four-taxon cases, tend to overestimate the support for tree topologies. furthermore, because of poor taxon sampling four-taxon analyses suffer from sensitivity to the long branch attraction artifact. here we extend the probability mapping approach by improving taxon sampling o ...200312974984
experimental determination and system level analysis of essential genes in escherichia coli mg1655.defining the gene products that play an essential role in an organism's functional repertoire is vital to understanding the system level organization of living cells. we used a genetic footprinting technique for a genome-wide assessment of genes required for robust aerobic growth of escherichia coli in rich media. we identified 620 genes as essential and 3,126 genes as dispensable for growth under these conditions. functional context analysis of these data allows individual functional assignment ...200313129938
a noncognate aminoacyl-trna synthetase that may resolve a missing link in protein evolution.efforts to delineate the advent of many enzymes essential to protein translation are often limited by the fact that the modern genetic code evolved before divergence of the tree of life. glutaminyl-trna synthetase (glnrs) is one noteworthy exception to the universality of the translation apparatus. in eukaryotes and some bacteria, this enzyme is essential for the biosynthesis of gln-trnagln, an obligate intermediate in translation. glnrs is absent, however, in archaea, and most bacteria, organel ...200313679580
complete genome sequence and analysis of wolinella succinogenes.to understand the origin and emergence of pathogenic bacteria, knowledge of the genetic inventory from their nonpathogenic relatives is a prerequisite. therefore, the 2.11-megabase genome sequence of wolinella succinogenes, which is closely related to the pathogenic bacteria helicobacter pylori and campylobacter jejuni, was determined. despite being considered nonpathogenic to its bovine host, w. succinogenes holds an extensive repertoire of genes homologous to known bacterial virulence factors. ...200314500908
infectious causes of acute flaccid paralysis.although acute flaccid paralysis (afp) is more frequently seen in the tropics than in temperate regions, recent outbreaks of west nile virus (wnv) in north america have drawn attention to this important presentation. starting with anatomical and neurophysiological considerations, this article examines data on afp caused by wnv, and considers recent data on paralysis caused by enteroviruses, and guillain-barré syndrome (gbs).200314501988
prevalence of campylobacter within a swine slaughter and processing facility.in this work, the occurrence of campylobacter in a swine slaughter and processing facility was studied. thirty composite carcass samples, representing 360 swine carcasses, were taken immediately after exsanguination, immediately after polishing, after the final wash, and after overnight chilling at 2 degrees c. thirty matching composite rectal samples were also taken immediately after exsanguination, and 60 nonmatching individual colon samples were collected from the same lot of swine during evi ...200314503704
conditions in lairages at abattoirs for ruminants in southwest england and in vitro survival of escherichia coli o157, salmonella kedougou, and campylobacter jejuni on lairage-related substrates.information on lairages (regarding design, construction materials, and use of bedding and cleaning regimes) was collected for 21 commercial cattle and/or sheep abattoirs in southwest england. overall, roughened or grooved concrete was the most common lairage flooring material. straw bedding was used in the majority of lairages and was changed between animal batches, daily, weekly, and monthly in roughly 5, 60, 15, and 10%, respectively, of the surveyed lairages. lairages were commonly washed wit ...200314503707
survival and persistence of campylobacter and salmonella species under various organic loads on food contact surfaces.although many cases of campylobacter and salmonella enteritis have been attributed to the undercooking of poultry and other foods, cross-contamination between raw and cooked foods via food contact surfaces and worker contact has also been identified as a significant risk factor. cross-contamination may be particularly important in relation to the high prevalence of contamination in raw poultry products and other foods and the low infectious doses that have been reported for campylobacter species ...200314503710
detection and enumeration of campylobacter jejuni and campylobacter coli by indirect impedimetry with an oxygen scavenging system.six strains of campylobacter jejuni and campylobacter coli were shown to grow in a variety of media, but, with one exception, they were unable to produce sufficient change in the electrical properties of the medium to allow their detection by impedance monitoring. with the use of an indirect method based on absorption of evolved carbon dioxide and a medium containing the oxygen scavenger oxyrase, all strains were detectable, and correlations between time to detection and the logarithm of the ino ...200314503735
antibiotic-dependent induction of pseudomonas putida dot-t1e ttgabc efflux pump is mediated by the drug binding repressor ttgr.pseudomonas putida is well known for its metabolic capabilities, but recently, it has been shown to exhibit resistance to a wide range of antibiotics. in p. putida dot-t1e, the ttgabc efflux pump, which has a broad substrate specificity, extrudes antibiotics such as ampicillin, carbenicillin, tetracycline, nalidixic acid, and chloramphenicol. we have analyzed the expression of the ttgabc efflux pump operon and its regulatory gene, ttgr, in response to several structurally unrelated antibiotics a ...200314506010
an outbreak of campylobacter jejuni infection among conference delegates.campylobacter infection is one of the most commonly reported foodborne diseases in australia however, reported campylobacter outbreaks are rare. this report describes such an outbreak among delegates attending a 10 day international academic meeting in south australia during may 2001. a retrospective cohort study of the 29 delegates who attended the conference was conducted. a questionnaire was sent by email with a response rate of 93 per cent. ten cases (onset of diarrhoea while attending the c ...200314510066
strong associations between gene function and codon usage.the association between codon usage and gene function was analyzed in the complete genomes of eschericia coli, bacillus subtilis, lactococcus lactis and campylobacter jejuni, using the functional annotation provided by ncbi. two distinctly different ways of quantifying codon usage were used in the analysis. by using contingency tables it was found that for most amino acids a highly significant association with gene function exists for all species, indicating that codon usage at the level of indi ...200314510641
antibiotic resistance among campylobacter jejuni/coli strains acquired in sweden and abroad: a longitudinal study.antibiotic resistance was compared in 844 campylobacter jejuni/coli strains acquired outside sweden and 575 acquired in sweden during 1990-2002. there was a clear gradual increase in ciprofloxacin and tetracycline resistance among c. jejuni/coli strains acquired outside sweden during the 13 y period. this trend was not seen for erythromycin or in domestically acquired strains for any of the 3 antibiotics tested.200314514147
disinfectant susceptibility testing of avian and swine campylobacter isolates by a filtration method.the susceptibility testing of disinfectants against campylobacter jejuni and campylobacter coli strains from broilers and pigs was investigated. the filtration method european standard en 1040 was adapted to campylobacter cultures and validated with reference strains. two disinfectants were tested: 1% benzalkonium chloride active matter, as quaternary ammonium compound, and 0.63% sodium hypochlorite as chlorine-releasing agent. both disinfectants were effective against the 34 campylobacter strai ...200314516706
simultaneous detection of mutations associated with resistance to macrolides and quinolones in campylobacter jejuni and c. coli using a pcr-line probe assay.quinolone and macrolide resistance of campylobacter jejuni and campylobacter coli mainly depend on a mutation in gyra and in 23s rdna, respectively. in order to detect quinolone and/or macrolide resistant c. jejuni and c. coli strains, a macrolide and quinolone line probe assay (mq-lipa) was developed and 42 c. jejuni and c. coli strains were tested to evaluate the efficiency of the assay. profiles of the mutations in 23s rdna and in gyra characterized by mq-lipa agreed with resistance to macrol ...200314522100
application of real-time pcr for quantitative detection of campylobacter jejuni in poultry, milk and environmental water.campylobacter jejuni is a leading human food-borne pathogen. the rapid and sensitive detection of c. jejuni is necessary for the maintenance of a safe food/water supply. in this article, we present a real-time polymerase chain reaction (pcr) assay for quantitative detection of c. jejuni in naturally contaminated poultry, milk and environmental samples without an enrichment step. the whole assay can be completed in 60 min with a detection limit of approximately 1 cfu. the standard curve correlati ...200314522462
ribotyping characterisation of campylobacter isolates randomly collected from different sources in italy.in this study the potential for using the automated psti ribotyping as a primary library typing method to survey campylobacter and for identification of two thermophilic campylobacter jejuni and campylobacter coli species was evaluated. a total of 158 isolates randomly collected in italy from different sources were analyzed. a large percentage of chicken (28%), turkey (27%) and turkey meat (25%) isolates shared their ribotyping profiles (ribotypes) with those of humans, whereas the swine isolate ...200314522511
comparison of the bax system with a multiplex pcr method for simultaneous detection and identification of campylobacter jejuni and campylobacter coli in environmental samples.the campylobacter detection is performed by conventional culture methods and the identification of campylobacter jejuni and campylobacter coli is principally based on the hippurate hydrolysis test. the two major drawbacks of this biochemical test for species identification include the inconsistency of the results and the presence of atypical strains, which can lead to the misidentification of an isolate. as an alternative, multiplex polymerase chain reaction (mpcr) protocols for the simultaneous ...200314527799
a 6 x 6 drop plate method for simultaneous colony counting and mpn enumeration of campylobacter jejuni, listeria monocytogenes, and escherichia coli.a protocol was developed using 96-well plates and multichannel pipettes for serial dilutions, followed by drop plating on agar in a 6 x 6 format. this protocol permits simultaneous plating of six dilutions which greatly decreases the number of plates utilized thereby saving incubator space for organisms such as campylobacter which require unique environmental conditions.200314529971
using quantitative real-time pcr to determine the hygienic status of cattle manure.we developed a suitable system of dna extraction and real-time quantitative polymerase chain reaction (qpcr) for the specific and sensitive quantification of pathogens and other relevant (indicator) organisms in recalcitrant material such as cattle manure. pcr inhibition by coextraction of humic compounds was minimized in this system, resulting in detection sensitivity of one target dna copy per reaction well. data from qpcr analysis for escherichia coli agreed with cultivation based results, bu ...200314531427
a model to estimate the optimal sample size for microbiological surveys.estimating optimal sample size for microbiological surveys is a challenge for laboratory managers. when insufficient sampling is conducted, biased inferences are likely; however, when excessive sampling is conducted valuable laboratory resources are wasted. this report presents a statistical model for the estimation of the sample size appropriate for the accurate identification of the bacterial subtypes of interest in a specimen. this applied model for microbiology laboratory use is based on a b ...200314532078
application of host-specific bacteriophages to the surface of chicken skin leads to a reduction in recovery of campylobacter jejuni.retail poultry products are widely purported as the major infection vehicle for human campylobacteriosis. numerous intervention strategies have sought to reduce campylobacter contamination on broiler carcasses in the abattoir. this study reports the efficacy of bacteriophage in reducing the number of recoverable campylobacter jejuni cells on artificially contaminated chicken skin.200314532096
comparison of campylobacter isolates from poultry and humans: association between in vitro virulence properties, biotypes, and pulsed-field gel electrophoresis clusters.the in vitro virulence properties of 197 temporally and geographically related campylobacter isolates from chicken broilers and humans were compared. comparisons of the virulence properties associated with genotypes and biotypes were made. all isolates adhered to, and 63% invaded, int-407 cells, whereas 13% were cytotoxic for cho cells. cho cell-cytotoxic extracts were also cytotoxic for int-407 cells, but the sensitivity for vero cells was variable. the proportion of isolates demonstrating a hi ...200314532099
molecular subtyping of vibrio cholerae o1 and o139 by pulsed-field gel electrophoresis in hong kong: correlation with epidemiological events from 1994 to 2002.two hundred twenty isolates of vibrio cholerae o1 and o139 collected from 1994 to 2002 in hong kong were analyzed by pulsed-field gel electrophoresis (pfge). chromosomal dnas from all v. cholerae isolates in agarose plugs were digested with the restriction enzyme noti, resulting in 20 to 27 bands. sixty distinctive pfge patterns in the range of 10 to 300 kb were noted among 213 isolates typeable by pfge. by comparing the common pfge patterns obtained from four well-defined outbreaks of v. choler ...200314532174
evaluation of protocol using gene capture and pcr for detection of helicobacter pylori dna in feces.the route of transmission of helicobacter pylori, which is usually acquired in childhood and is one of the most common bacterial infections in humans, remains undetermined. mapping the distribution of h. pylori genotypes within families could help to determine the routes of transmission and risk factors. here we describe a noninvasive method for obtaining h. pylori dna isolates from the feces of children. children presenting with gastrointestinal symptoms at the royal hospital for sick children ...200314532187
diagnosis of helicobacter pylori infection in adults with intellectual disability.helicobacter pylori infection is common among adults with intellectual disability. the acceptabilities and accuracies of different diagnostic tests in this population are unknown. we aimed to determine (i) patient acceptability and (ii) performance characteristics of serology, fecal-antigen, and urea breath tests among adults with intellectual disability. one hundred sixty-eight such adults underwent h. pylori testing with serology and fecal-antigen tests, and a portion underwent treatment. one ...200314532206
utility of multilocus sequence typing as an epidemiological tool for investigation of outbreaks of gastroenteritis caused by campylobacter jejuni.multilocus sequence typing (mlst) has been proven useful for the study of the global population structure of campylobacter jejuni; however, its usefulness for the investigation of outbreaks of disease caused by c. jejuni has not been proven. in this study, mlst plus sequencing of the flaa short variable region (svr) were applied to 47 isolates from 12 outbreaks of c. jejuni infection whose relatedness has been determined previously, and the results were compared to those of serotyping and pulsed ...200314532212
temporal and geographical distribution and overlap of penner heat-stable serotypes and pulsed-field gel electrophoresis genotypes of campylobacter jejuni isolates collected from humans and chickens in finland during a seasonal peak.the association of penner heat-stable serotypes and pulsed-field gel electrophoresis genotypes of 208 human and 30 chicken campylobacter jejuni isolates was studied. overall, 46% of the human strains had overlapping sero- and genotype combinations with chicken strains. the percentage was reduced to 31% for strains that were considered temporally related. this suggests common environmental sources.200314532246
high prevalence of atypical enteropathogenic escherichia coli (epec) in norwegian children with diarrhoea.the aim of the present study was to investigate the relative contribution of enteropathogenic escherichia coli (epec) as a cause of infectious diarrhoea in norwegian children. data from faecal specimens from children <2 years old with diarrhoea during the year 2001 were analysed. e. coli isolates with the attaching and effacing genotype (eae+) were examined for the presence of the bundle-forming pilus (bfpa) and shiga toxin genes by pcr, and for genetic relatedness by pfge. during the 1-year per ...200314532347
cloning, preliminary characterization and crystallization of nucleoside hydrolases from caenorhabditis elegans and campylobacter jejuni.the nucleoside hydrolases (nhs) are a family of nucleoside-modifying enzymes. they play an important role in the purine-salvage pathway of many pathogenic organisms which are unable to synthesize purines de novo. although well characterized in protozoan parasites, their precise function and mechanism remain unclear in other species. for the first time, nhs from caenorhabditis elegans and campylobacter jejuni, which are representatives of mesozoa and bacteria, respectively, have been cloned and p ...200312777783
seasonal variation in bacterial pathogens isolated from stool samples in karachi, pakistan.to determine the seasonal variation of the commonly isolated bacterial pathogens in stool samples.200312779031
campylobacter--a tale of two protein glycosylation systems.post-translational glycosylation is a universal modification of proteins in eukarya, archaea and bacteria. two recent publications describe the first confirmed report of a bacterial n-linked glycosylation pathway in the human gastrointestinal pathogen campylobacter jejuni. in addition, an o-linked glycosylation pathway has been identified and characterized in c. jejuni and the related species campylobacter coli. both pathways have similarity to the respective n- and o-linked glycosylation proces ...200312781527
campylobacter jejuni contamination on broiler carcasses of c. jejuni-negative flocks during processing in a japanese slaughterhouse.at a slaughterhouse, we determined the campylobacter jejuni status of each broiler flock coming from different farms by culturing cecal contents of representative birds, and examined the prevalence of c. jejuni on carcasses during processing. then, c. jejuni isolates from the carcasses were typed with rapd pcr and compared with those from the cecal contents of a c. jejuni-positive flock. c. jejuni was not isolated from the carcasses of c. jejuni-negative flocks processed before the c. jejuni-pos ...200312781960
characterization of urease-positive thermophilic campylobacter subspecies by multilocus enzyme electrophoresis typing.thirty-one urease-positive thermophilic campylobacter (uptc) isolates, including three reference strains (nctc12892, nctc12895 and nctc12896), and three campylobacter lari isolates, which were isolated from several countries and sources, were compared genotypically by using multilocus enzyme electrophoresis (mlee). we examined allelic variation around seven enzyme loci, including the adenylate kinase, alkaline phosphatase, catalase, fumarase, malic enzyme, malate dehydrogenase, and l-phenylalany ...200312788730
use of pcr for direct detection of campylobacter species in bovine feces.this study reports on the use of pcr to directly detect and distinguish campylobacter species in bovine feces without enrichment. inhibitors present in feces are a major obstacle to using pcr to detect microorganisms. the qiaamp dna stool minikit was found to be an efficacious extraction method, as determined by the positive amplification of internal control dna added to bovine feces before extraction. with nested or seminested multiplex pcr, campylobacter coli, c. fetus, c. hyointestinalis, and ...200312788747
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