TitleAbstractYear(sorted ascending)
antimicrobial susceptibility trends in campylobacter jejuni and campylobacter coli isolated from a rural egyptian pediatric population with diarrhea.comparative and trend analysis was conducted on annual prevalence of antimicrobial susceptibility among campylobacter jejuni and campylobacter coli recovered from rural egyptian children from 1995 through 2000. c. jejuni and c. coli demonstrated significant decreasing trends in ciprofloxacin susceptibility over the study period (p < 0.001 for both). in general, c. coli demonstrated a higher degree of susceptibility than c. jejuni, however, there was no statistical difference (p = 0.2) comparing ...200314711482
a survey of campylobacter species shed in faeces of beef cattle using polymerase chain reaction.a polymerase chain reaction (pcr)-based survey of campylobacters associated with faeces collected from 382 beef cattle was undertaken. to ensure the removal of pcr inhibitors present in faeces and determine if adequate extraction was achieved, faeces were seeded with internal control dna (i.e., dna designed to amplify with the campylobacter genus primer set, but provide a smaller amplicon) before the extraction procedure. in only two samples (0.5%) were the internal control or campylobacter genu ...200314735214
antibiotic susceptibility of campylobacter jejuni and campylobacter coli human isolates from bosnia and herzegovina. 200312654755
antimicrobial resistance of campylobacter jejuni and campylobacter coli isolates from broiler chickens isolated at an irish poultry processing plant.the antibiotic susceptibility of campylobacter jejuni and campylobacter coli isolates from broiler chickens were determined in order to evaluate the level of antibiotic resistance of campylobacter species in the irish poultry industry.200312680938
prevalence of cytolethal distending toxin production in periodontopathogenic bacteria.cytolethal distending toxin (cdt) is a newly identified virulence factor produced by several pathogenic bacteria implicated in chronic infection. seventy three strains of periodontopathogenic bacteria were examined for the production of cdt by a hela cell bioassay and for the presence of the cdt gene by pcr with degenerative oligonucleotide primers, which were designed based on various regions of the escherichia coli and campylobacter cdtb genes, which have been successfully used for the identif ...200312682119
investigation of infectious agents associated with arthritis by reverse transcription pcr of bacterial reactive and postinfectious arthritis the joints are generally sterile but the presence of bacterial antigens and nucleic acids has been reported. to investigate whether organisms traffic to affected joints in these conditions, we performed reverse transcription pcr using universal primers to amplify any bacterial 16s rrna sequences present in synovial fluid. bacterial sequences were detected in most cases, even after treatment of the synovial fluid with dnase, implying the presence of bacter ...200312716447
investigation of infectious agents associated with arthritis by reverse transcription pcr of bacterial reactive and postinfectious arthritis the joints are generally sterile but the presence of bacterial antigens and nucleic acids has been reported. to investigate whether organisms traffic to affected joints in these conditions, we performed reverse transcription pcr using universal primers to amplify any bacterial 16s rrna sequences present in synovial fluid. bacterial sequences were detected in most cases, even after treatment of the synovial fluid with dnase, implying the presence of bacter ...200312716447
detection of conserved n-linked glycans and phase-variable lipooligosaccharides and capsules from campylobacter cells by mass spectrometry and high resolution magic angle spinning nmr spectroscopy.glycomics, the study of microbial polysaccharides and genes responsible for their formation, requires the continuous development of rapid and sensitive methods for the identification of glycan structures. in this study, methods for the direct analysis of sugars from 108 to 1010 cells are outlined using the human gastrointestinal pathogen, campylobacter jejuni. using capillary-electrophoresis coupled with sensitive electrospray mass spectrometry, we demonstrate variability in the lipid a componen ...200312716884
inhibition of helicobacter pylori growth in vitro by bulgarian propolis: preliminary report.bee glue (propolis) possesses antimicrobial, anti-inflammatory, anaesthetic and immunostimulating activities. the aim of the study was to evaluate the inhibitory effect of bulgarian propolis on helicobacter pylori growth in vitro. activity of 30% ethanolic extract of propolis (eep) against 38 clinical isolates of h. pylori was evaluated by using the agar-well diffusion method. ethanol was used as a control. in addition, the effect of propolis on the growth of 26 h. pylori and 18 campylobacter st ...200312721318
in vivo tracking of campylobacter jejuni by using a novel recombinant expressing green fluorescent protein.campylobacter jejuni is a leading cause of food-borne disease in developed countries. the goal of this study was to develop a plasmid-based reporter system with green fluorescent protein (gfp) to facilitate the study of c. jejuni in a variety of niches. c. jejuni transformants harboring the pmek91 gfp gene (gfp)-containing vector were readily detectable by both fluorescence microscopy and flow cytometry. given the ease of detecting these organisms, additional experiments were performed in which ...200312732559
antimicrobial-resistant campylobacter species from retail raw meats.the antimicrobial susceptibilities of 378 campylobacter isolates were determined. resistance to tetracycline was the most common (82%), followed by resistance to doxycycline (77%), erythromycin (54%), nalidixic acid (41%), and ciprofloxacin (35%). campylobacter coli displayed significantly higher rates of resistance to ciprofloxacin and erythromycin than campylobacter jejuni, and campylobacter isolates from turkey meat showed a greater resistance than those from chicken meat.200312732579
usefulness of the microseq 500 16s ribosomal dna-based bacterial identification system for identification of clinically significant bacterial isolates with ambiguous biochemical profiles.due to the inadequate automation in the amplification and sequencing procedures, the use of 16s rrna gene sequence-based methods in clinical microbiology laboratories is largely limited to identification of strains that are difficult to identify by phenotypic methods. in this study, using conventional full-sequence 16s rrna gene sequencing as the "gold standard," we evaluated the usefulness of the microseq 500 16s ribosomal dna (rdna)-based bacterial identification system, which involves amplifi ...200312734240
phenotypic and genotypic differentiation of campylobacter spp. isolated from austrian broiler farms: a identification scheme based on restriction fragment length polymorphism of polymerase chain reaction products (pcr-rflp) was developed to differentiate isolates of the genera campylobacter, arcobacter and helicobacter. based on the 16s rrna gene of these genera, pcr amplified a 1216-bp fragment. the amplicons were digested with the restriction enzymes rsai and ecorv. additional differentiation was obtained using a pcr-assay based on the hippuricase gene. genotyping was performed on several re ...200312745378
comparison of recovery methods for freeze-injured listeria monocytogenes, salmonella typhimurium, and campylobacter coli in cell suspensions and associated with pork surfaces.cells injured as a result of freezing, heating, and acidification treatments may not grow during conventional microbiological procedures owing to the presence of selective agents, compounds, or dyes in the media, impairing the cell's ability to repair itself and grow. injured cells can be recovered by combining selective and nonselective media into a single system. with such combinations, the diffusion of the selective compounds or dyes is controlled, allowing for the resuscitation of injured ce ...200312747688
pcr detection of seven virulence and toxin genes of campylobacter jejuni and campylobacter coli isolates from danish pigs and cattle and cytolethal distending toxin production of the study the prevalence of seven virulence and toxin genes, and cytolethal distending toxin (cdt) production of campylobacter jejuni and c. coli isolates from danish pigs and cattle.200312752808
antimicrobial resistance of campylobacter jejuni subsp. jejuni strains isolated from humans in 1998 to 2001 in montréal, canada.the rates of resistance of 51 to 72 human strains of campylobacter jejuni subsp. jejuni isolated annually from 1998 to 2001 in montréal, québec, canada, varied from 1 to 12% for erythromycin, 43 to 68% for tetracycline, and 10 to 47% for ciprofloxacin. in the last years of the study, there was a significant increase in the rate of resistance to ciprofloxacin (p = 0.00003) but not in the rate of resistance to erythromycin (p = 0.056) or tetracycline (p = 0.095) compared to the rate obtained in th ...200312760892
campylobacter--a tale of two protein glycosylation 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
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
rapid detection of campylobacter coli, c. jejuni, and salmonella enterica on poultry carcasses by using pcr-enzyme-linked immunosorbent assay.contamination of retail poultry by campylobacter spp. and salmonella enterica is a significant source of human diarrheal disease. isolation and identification of these microorganisms require a series of biochemical and serological tests. in this study, campylobacter ceue and salmonella inva genes were used to design probes in pcr-enzyme-linked immunosorbent assay (elisa), as an alternative to conventional bacteriological methodology, for the rapid detection of campylobacter jejuni, campylobacter ...200312788755
species-specific identification of campylobacters by partial 16s rrna gene sequencing.species-specific identification of campylobacters is problematic, primarily due to the absence of suitable biochemical assays and the existence of atypical strains. 16s rrna gene (16s rdna)-based identification of bacteria offers a possible alternative when phenotypic tests fail. therefore, we evaluated the reliability of 16s rdna sequencing for the species-specific identification of campylobacters. sequence analyses were performed by using almost 94% of the complete 16s rrna genes of 135 phenot ...200312791878
reduction of bacteria on pork carcasses associated with chilling addition to reducing the temperature of pork carcasses immediately after slaughter and before fabrication, blast chilling (snap chill) or conventional chilling can reduce bacterial populations associated with fresh meats. however, there is little information on bacteria survival resulting from the freeze or chill injury of meat products. in this study, porcine fecal slurries with and without pathogens (listeria monocytogenes, salmonella typhimurium, and campylobacter coli) were inoculated ont ...200312801003
comparison of eight phenotypic methods for subspecies characterization of thermophilic campylobacter spp. isolated from pig liver.four hundred pork livers from bacon pigs (37 herds) obtained at six pig-processing plants were studied to assess the campylobacter contamination rate. deep tissue areas were sampled immediately after evisceration. approximately 6% of livers were infected with campylobacter spp., including campylobacter coli (67%), campylobacter jejuni (30%), and campylobacter lari (3%). the 60 resulting isolates (39 c. coli isolates, 19 c. jejuni isolates, and 2 c. lari isolates) employed in this study were char ...200312801013
the complete genome sequence of the carcinogenic bacterium helicobacter hepaticus.helicobacter hepaticus causes chronic hepatitis and liver cancer in mice. it is the prototype enterohepatic helicobacter species and a close relative of helicobacter pylori, also a recognized carcinogen. here we report the complete genome sequence of h. hepaticus atcc51449. h. hepaticus has a circular chromosome of 1,799,146 base pairs, predicted to encode 1,875 proteins. a total of 938, 953, and 821 proteins have orthologs in h. pylori, campylobacter jejuni, and both pathogens, respectively. h. ...200312810954
infectious agent and immune response characteristics of chronic enterocolitis in captive rhesus macaques.chronic enterocolitis is the leading cause of morbidity in colonies of captive rhesus macaques (macaca mulatta). this study's aim was to identify the common enteric pathogens frequently associated with chronic enterocolitis in normal, immunocompetent rhesus monkeys and to elucidate the influence of this clinical syndrome on the host immune system. we analyzed the fecal specimens from 100 rhesus macaques with or without clinical symptoms of chronic diarrhea. retrospective analysis revealed an inc ...200312819098
helicobacter pylori preferentially induces interleukin 12 (il-12) rather than il-6 or il-10 in human dendritic cells.dendritic cells are potent antigen-presenting cells that are present in the gastrointestinal tract and are required for the induction of a th1 t-cell acquired immune response. since infection with the gastric pathogen helicobacter pylori elicits a th1 cell response, the interaction of these organisms with dendritic cells should reflect the th1 bias. we incubated h. pylori with cultured human dendritic cells and measured the cytokine induction profile, comparing the response to that induced by sa ...200312819109
campylobacter coli - an important foodborne pathogen.campylobacters are the most common bacterial cause of infectious intestinal disease (iid) in temperate countries. c. jejuni is the predominant cause of campylobacter iid, but the impact of other, less prevalent species has largely been ignored. here, we present estimates of the burden of indigenously acquired foodborne disease (ifd) due to campylobacter coli, the second most common cause of human campylobacteriosis.200312850159
[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
sources of campylobacter colonization in broiler chickens. 200312902214
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
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
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
prevalence of multiple antibiotic resistance in 443 campylobacter spp. isolated from humans and 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
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
comparison of human and porcine strains of campylobacter coli. 200312930063
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
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 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
toward an international standard for pcr-based detection of food-borne thermotolerant campylobacters: assay development and analytical 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 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
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
production of cytolethal distending toxins by pathogenic escherichia coli strains isolated from human and animal sources: establishment of the existence of a new cdt variant (type iv).three types of cytolethal distending toxin (cdt), namely, cdt-i, cdt-ii, and cdt-iii, have been described in escherichia coli. using primers designed for the detection of sequences common to the cdtb genes, we analyzed by pcr a set of 21 cdt-producing e. coli strains of intestinal and extraintestinal origins isolated from human and different animal species in several european countries and in the united states. on the basis of the existing differences in the cdtb genes, cdt-i-, cdt-ii-, and cdt- ...200312958258
resistance to quinolones in campylobacter jejuni and campylobacter coli from danish broilers at farm investigate the prevalence of quinolone resistance among campylobacter jejuni and camp. coli isolates from danish poultry at the farm level, as well as for the whole country.200312492931
association of helicobacter pylori antioxidant activities with host colonization assess the importance of two separate antioxidant activities in helicobacter pylori, we tested the abilities of strains with mutations in either tpx (encoding thiolperoxidase) or ahpc (encoding alkyl hydroperoxide reductase [ahpc]) to colonize the stomachs of mice. the tpx strain was clearly more sensitive than the parent strain to both oxygen and cumene hydroperoxide. the strain colonized only 5% of the inoculated mice. two different classes of oxygen-sensitive ahpc mutants in the type strai ...200312496216
antimicrobial susceptibilities of campylobacter strains isolated from finnish subjects infected domestically or from those infected abroad.the in vitro susceptibilities of 678 campylobacter jejuni and campylobacter coli strains isolated from stool samples of the same number of finnish subjects were studied. a total of 523 patients, representing inhabitants from throughout finland, had not traveled abroad within the 2 weeks prior to becoming ill, whereas 155 persons had presumably acquired their infections abroad. the antimicrobial agents studied were erythromycin, ciprofloxacin, levofloxacin, trovafloxacin, and moxifloxacin. the mi ...200312499176
enhanced surveillance of campylobacter infection in the north west of england identify sources and routes of infection for sporadic cases of campylobacter infection in the north west of england.200312504607
survival and resuscitation of ten strains of campylobacter jejuni and campylobacter coli under acid conditions.the culturability of 10 strains of campylobacter jejuni and campylobacter coli was studied after the bacteria were exposed to acid conditions for various periods of time. campylobacter cells could not survive 2 h under acid conditions (formic acid at ph 4). the 10 campylobacter strains could not be recovered, even when enrichment media were used. viable cells, however, could be detected by a double-staining (5-cyano-2,3-ditolyl tetrazolium chloride [ctc]-4',6'-diamidino-2-phenylindole [dapi]) te ...200312514068
comparative genotyping of campylobacter jejuni by amplified fragment length polymorphism, multilocus sequence typing, and short repeat sequencing: strain diversity, host range, and recombination.three molecular typing methods were used to study the relationships among 184 campylobacter strains isolated from humans, cattle, and chickens. all strains were genotyped by amplified fragment length polymorphism (aflp) analysis, multilocus sequence typing (mlst), and sequence analysis of a genomic region with short tandem repeats designated clustered regularly interspaced short palindromic repeats (crisprs). mlst and aflp analysis yielded more than 100 different profiles and patterns, respectiv ...200312517820
molecular assays for detection of human metapneumovirus.the recent description of the respiratory pathogen human metapneumovirus (hmpv) has highlighted a deficiency in current diagnostic techniques for viral agents associated with acute lower respiratory tract infections. we describe two novel approaches to the detection of viral rna by use of reverse transcriptase pcr (rt-pcr). the pcr products were identified after capture onto a solid-phase medium by hybridization with a sequence-specific, biotinylated oligonucleotide probe. the assay was applied ...200312517833
evaluation of 11 pcr assays for species-level identification of campylobacter jejuni and campylobacter coli.we examined the sensitivity and specificity of 11 pcr assays described for the species identification of campylobacter jejuni and campylobacter coli by using 111 type, reference, and field strains of c. jejuni, c. coli, and campylobacter lari. for six assays, an additional 21 type strains representing related campylobacter, arcobacter, and helicobacter species were also included. pcr tests were initially established in the laboratory by optimizing conditions with respect to five type and referen ...200312517869
real-time pcr assay for rapid and accurate detection of point mutations conferring resistance to clarithromycin in helicobacter pylori.the main cause of failure of helicobacter pylori eradication therapy is resistance to clarithromycin. the resistance is due to three point mutations in two positions on the 23s rrna (a2142c, a2142g, and a2143g). our aim was to develop a rapid and accurate method to detect these mutations directly on biopsy specimens. we developed a real-time pcr that included a simultaneous detection of the amplicons by hybridization of two probes labeled with lc-red and fluorescein by using the fluorescence res ...200312517879
epidemiology and antimicrobial susceptibilities of 111 campylobacter fetus subsp. fetus strains isolated in québec, canada, from 1983 to 2000.the epidemiology and antimicrobial susceptibilities of 111 campylobacter fetus subsp. fetus strains isolated from 103 patients from 1983 to 2000 in québec, canada, were determined. the median number of patients infected annually with this bacteria was seven, with an incidence of 0.1 per 100,000 population. the male-to-female ratio was 1.1 to 1.0. the patients originated from 13 of the 18 québec socioeconomic regions. the age range of the patients was 6 months to 90 years old, 53% being > or = 70 ...200312517895
the gam protein of bacteriophage mu is an orthologue of eukaryotic bacteriophage inserts its dna into the genome of host bacteria and is used as a model for dna transposition events in other systems. the eukaryotic ku protein has key roles in dna repair and in certain transposition events. here we show that the gam protein of phage mu is conserved in bacteria, has sequence homology with both subunits of ku, and has the potential to adopt a similar architecture to the core dna-binding region of ku. through biochemical studies, we demonstrate that gam and the ...200312524520
characterization of helicobacter pylori nickel metabolism accessory proteins needed for maturation of both urease and hydrogenase.previous studies demonstrated that two accessory proteins, hypa and hypb, play a role in nickel-dependent maturation of both hydrogenase and urease in helicobacter pylori. here, the two proteins were purified and characterized. hypa bound two ni(2+) ions per dimer with positive cooperativity (hill coefficient, approximately 2.0). the dissociation constants k(1) and k(2) for ni(2+) were 58 and 1.3 microm, respectively. studies on purified site-directed mutant proteins in each of the five histidin ...200312533448
the iron-binding protein dps confers hydrogen peroxide stress resistance to campylobacter jejuni.we identified and characterized the iron-binding protein dps from campylobacter jejuni. electron microscopic analysis of this protein revealed a spherical structure of 8.5 nm in diameter, with an electron-dense core similar to those of other proteins of the dps (dna-binding protein from starved cells) family. cloning and sequencing of the dps-encoding gene (dps) revealed that a 450-bp open reading frame (orf) encoded a protein of 150 amino acids with a calculated molecular mass of 17,332 da. ami ...200312533477
evaluation of broiler litter with reference to the microbial composition as assessed by using 16s rrna and functional gene markers.very little is known about the microbial composition of animal bedding wastes, including poultry litter, and what is known has been deduced from standard culture methods, by which some fastidious organisms that exist in the environment may not be detected. we evaluated the bacterial composition of poultry litter by using a combination of culture and molecular detection. total aerobic bacteria in poultry litter were detected by culture at 10(9) cfu/g of material. enteric bacteria such as enteroco ...200312571010
specific detection of arcobacter and campylobacter strains in water and sewage by pcr and fluorescent in situ hybridization.the aim of this study was to evaluate pcr and fluorescent in situ hybridization (fish) techniques for detecting arcobacter and campylobacter strains in river water and wastewater samples. both 16s and 23s rrna sequence data were used to design specific primers and oligonucleotide probes for pcr and fish analyses, respectively. in order to assess the suitability of the methods, the assays were performed on naturally and artificially contaminated samples and compared with the isolation of cells on ...200312571045
occurrence and resistance to antibiotics of campylobacter jejuni and campylobacter coli in animals and meat in northeastern italy.a study was carried out in northeastern italy during 2000 and 2001 to investigate the occurrence of campylobacter jejuni and campylobacter coli in animals, cattle, pigs, and broilers, and raw meat, beef, pork, and chicken. campylobacter spp. were detected in 53.9% of the cattle, 63.5% of the pigs, and 82.9% of the broilers examined. chicken meat was frequently contaminated (81.3%), while lower rates were found in pork meat (10.3%) and beef (1.3%). the resistance to antibiotics of the strains was ...200312593931
gastroenteritis in nf-kappab-deficient mice is produced with wild-type camplyobacter jejuni but not with c. jejuni lacking cytolethal distending toxin despite persistent colonization with both strains.campylobacter jejuni continues to be a leading cause of bacterial enteritis in humans. however, because there are no readily available animal models to study the pathogenesis of c. jejuni-related diseases, the significance of potential virulence factors, such as cytolethal distending toxin (cdt), in vivo are poorly understood. mice deficient in nf-kappab subunits (p50(-/-) p65(+/-)) in a c57bl/129 background are particularly susceptible to colitis induced by another enterohepatic microaerobe, he ...200414742559
proteomic analysis of the sarcosine-insoluble outer membrane fraction of helicobacter pylori strain 26695.helicobacter pylori causes gastroduodenal disease, which is mediated in part by its outer membrane proteins (omps). to identify omps of h. pylori strain 26695, we performed a proteomic analysis. a sarcosine-insoluble outer membrane fraction was resolved by two-dimensional electrophoresis with immobilized ph gradient strips. most of the protein spots, with molecular masses of 10 to 100 kda, were visible on the gel in the alkaline pi regions (6.0 to 10.0). the proteome of the omps was analyzed by ...200414761989
genotypic and antibiotic susceptibility characteristics of a campylobacter coli population isolated from dairy farmland in the united kingdom.campylobacter infections are the most common cause of bacterial enteritis in humans, and nearly 8% of such infections are caused by campylobacter coli. most studies have concentrated on campylobacter jejuni, frequently isolated from intensively farmed poultry and livestock production units, and few studies have examined the spread and relatedness of campylobacter across a range of geographical and host boundaries. systematic sampling of a 100-km2 area of mixed farmland in northwest england yield ...200414766560
comparison of survival of campylobacter jejuni in the phyllosphere with that in the rhizosphere of spinach and radish plants.campylobacter jejuni has been isolated previously from market produce and has caused gastroenteritis outbreaks linked to produce. we have tested the ability of this human pathogen to utilize organic compounds that are present in leaf and root exudates and to survive in the plant environment under various conditions. carbon utilization profiles revealed that c. jejuni can utilize many organic acids and amino acids available on leaves and roots. despite the presence of suitable substrates in the p ...200414766604
simultaneous presence of multiple campylobacter species in dogs.the prevalence of coinfection of campylobacter species in dogs was determined using four isolation methods. in 26% of the positive-testing stools, multiple campylobacter species were identified. the use of multiple isolation methods as well as the time lapse between sampling and processing are important for detection of coinfection.200414766860
campylobacter spp., giardia spp., cryptosporidium spp., noroviruses, and indicator organisms in surface water in southwestern finland, 2000-2001.a total of 139 surface water samples from seven lakes and 15 rivers in southwestern finland were analyzed during five consecutive seasons from autumn 2000 to autumn 2001 for the presence of various enteropathogens (campylobacter spp., giardia spp., cryptosporidium spp., and noroviruses) and fecal indicators (thermotolerant coliforms, escherichia coli, clostridium perfringens, and f-rna bacteriophages) and for physicochemical parameters (turbidity and temperature); this was the first such systema ...200414711629
fluorescent amplified fragment length polymorphism genotyping of campylobacter jejuni and campylobacter coli strains and its relationship with host specificity, serotyping, and phage typing.fluorescent amplified fragment length polymorphism (faflp) analysis was applied to 276 campylobacter jejuni strains and 87 campylobacter coli strains isolated from humans, pigs, cattle, poultry, and retail meats to investigate whether certain faflp genotypes of c. jejuni and c. coli are associated with a particular host and to determine the degree of association between faflp-defined genotypes and heat-stable serotypes and/or phage types. within c. coli, the poultry strains clustered separately ...200414715757
the neuc protein of escherichia coli k1 is a udp n-acetylglucosamine 2-epimerase.the k1 capsule is an essential virulence determinant of escherichia coli strains that cause meningitis in neonates. biosynthesis and transport of the capsule, an alpha-2,8-linked polymer of sialic acid, are encoded by the 17-kb kps gene cluster. we deleted neuc, a k1 gene implicated in sialic acid synthesis, from the chromosome of ev36, a k-12-k1 hybrid, by allelic exchange. exogenously added sialic acid restored capsule expression to the deletion strain (deltaneuc), confirming that neuc is nece ...200414729696
characterization of a haemolytic phospholipase a(2) activity in clinical isolates of campylobacter concisus.a membrane-bound, haemolytic phospholipase a(2) (pla(2)) activity was detected in clinical strains of campylobacter concisus isolated from children with gastroenteritis. the clinical strains were assigned into two molecular groups (genomospecies) based on pcr amplification of their 23s rdna. this calcium-dependent, heat-stable, haemolytic pla(2) activity was detected in strains from both genomospecies. a crude haemolysin extract (che) was initially prepared from cellular outer-membrane proteins ...200415150326
prevalence and antimicrobial resistance of campylobacter coli isolated from fattening pigs in france.campylobacter are a leading cause of human diarrhea. the usual source of infection is contaminated food, particularly poultry but pork has also been described. the veterinary use of antimicrobial drugs has been suggested to be largely responsible for resistance in human isolates of this zoonotic pathogen. a study was carried out to investigate the occurrence and antimicrobial resistance of campylobacter isolated from french fattening pigs. from march 1998 to june 1999, stomach samples were colle ...200415172691
antimicrobial resistance among enteric pathogens.diarrhea is a major cause of morbidity and mortality in infants and children worldwide. use of antimicrobial therapy in children with bacterial diarrhea involves consideration of advantages and limitations of use of appropriate agents in the general population and in specific hosts. antimicrobial agents for bacterial diarrhea should be prescribed with an appreciation of limitations including antimicrobial resistance. studies from many countries have reported resistance to campylobacter jejuni, c ...200415185189
characterization of erythromycin resistance in campylobacter coli and campylobacter jejuni isolated from pig offal in new determine the level and mechanism(s) of antimicrobial resistance in campylobacter isolates obtained from human and environmental sources from south canterbury, new zealand.200415186451
in vitro inhibitory activity of chinese leek extract against campylobacter species.three aqueous extracts of dietary materials of chinese leek (leek flower stem, soft leek and green leek) and two other reference extracts of allium plants were used to investigate the antibacterial effects against campylobacter jejuni and campylobacter coli. all the tested strains of campylobacter species were isolated from chickens. the minimum concentration of aqueous leek extracts (ales) required to inhibit the bacterial growth was 2.0 mg/ml. among the plant extracts tested, ales shared the l ...200415193803
genotyping of broiler-originated campylobacter jejuni and campylobacter coli isolates using fla typing and random amplified polymorphic dna methods.liver and intestine samples taken from 200 broilers at 20 flocks were inoculated onto preston enrichment broth and agar for selective isolation of campylobacter jejuni and campylobacter coli. the isolates were identified by both conventional and polymerase chain reaction (pcr) methods. campylobacter spp. were identified in 102 of 400 samples (200 liver and 200 intestine), 57 (14.25%) of which were identified as c. jejuni and 45 (11.25%) as c. coli. pcr-restriction fragment length polymorphism (r ...200415193806
relapsing cellulitis associated with campylobacter coli bacteremia in an agammaglobulinemic patient.campylobacter coli rarely causes bacteremia or extraintestinal infection. we report herein a case of agammaglobulinemia in which cellulitis associated with c. coli bacteremia relapsed after a disease-free interval of >5 years. pulsed field gel electrophoresis revealed that the organisms in this patient were genetically identical, suggesting a latent c. coli infection.200415194845
quinolone-resistant campylobacter infections: risk factors and clinical consequences.we integrated data on quinolone and macrolide susceptibility patterns with epidemiologic and typing data from campylobacter jejuni and c. coli infections in two danish counties. the mean duration of illness was longer for 86 patients with quinolone-resistant c. jejuni infections (median 13.2 days) than for 381 patients with quinolone-sensitive c. jejuni infections (median 10.3 days, p = 0.001). foreign travel, eating fresh poultry other than chicken and turkey, and swimming were associated with ...200415207057
adaptation of campylobacter jejuni nctc11168 to high-level colonization of the avian gastrointestinal tract.the genome sequence of the human pathogen campylobacter jejuni nctc11168 has been determined recently, but studies on colonization and persistence in chickens have been limited due to reports that this strain is a poor colonizer. experimental colonization and persistence studies were carried out with c. jejuni nctc11168 by using 2-week-old light sussex chickens possessing an acquired natural gut flora. after inoculation, nctc11168 initially colonized the intestine poorly. however, after 5 weeks ...200415213117
molecular characterization of benzimidazole resistance in helicobacter pylori.a family of benzimidazole derivatives (bi) was shown to possess potent and selective activity against helicobacter pylori, although the precise cellular target of the bis is unknown. spontaneous h. pylori mutants were isolated as resistant to a representative bi (compound a). genomic dna was isolated from a bi-resistant mutant, transformed into a bi-sensitive strain, and found to be sufficient to confer bi resistance. the resistance determinant was localized to a 17-kb clone after screening a la ...200415215104
helicobacter pylori flgr is an enhancer-independent activator of sigma54-rna polymerase holoenzyme.helicobacter pylori flgr activates transcription with sigma54-rna polymerase holoenzyme (sigma54-holoenzyme) from at least five flagellar operons. activators of sigma54-holoenzyme generally bind enhancer sequences located >70 bp upstream of the promoter and contact sigma54-holoenzyme bound at the promoter through dna looping to activate transcription. h. pylori flgr lacks the carboxy-terminal dna-binding domain present in most sigma54-dependent activators. as little as 42 bp of dna upstream of t ...200415231786
iron acquisition and regulation in campylobacter jejuni.iron affects the physiology of bacteria in two different ways: as a micronutrient for bacterial growth and as a catalyst for the formation of hydroxyl radicals. in this study, we used dna microarrays to identify the c. jejuni genes that have their transcript abundance affected by iron availability. the transcript levels of 647 genes were affected after the addition of iron to iron-limited c. jejuni cells. several classes of affected genes were revealed within 15 min, including immediate-early re ...200415231804
longitudinal study of campylobacter jejuni bacteriophages and their hosts from broiler chickens.a longitudinal study of bacteriophages and their hosts was carried out at a broiler house that had been identified as having a population of campylobacter-specific bacteriophages. cloacal and excreta samples were collected from three successive broiler flocks reared in the same barn. campylobacter jejuni was isolated from each flock, whereas bacteriophages could be isolated from flocks 1 and 2 but were not isolated from flock 3. the bacteriophages isolated from flocks 1 and 2 were closely relate ...200415240258
identification of bacterial populations in dairy wastewaters by use of 16s rrna gene sequences and other genetic markers.hydraulic flush waste removal systems coupled to solid/liquid separators and circulated treatment lagoons are commonly utilized to manage the large amounts of animal waste produced on high-intensity dairy farms. although these systems are common, little is known about the microbial populations that inhabit them or how they change as they traverse the system. using culture-based and non-culture-based methods, we characterized the microbial community structure of manure, water from the separator p ...200415240310
multiplex pcr assay for detection of streptococcus suis species and serotypes 2 and 1/2 in tonsils of live and dead pigs.a pcr assay was developed for the detection of streptococcus suis serotypes 2 and 1/2. this multiplex pcr is based on the amplification of the gene coding for 16s rrna of s. suis and on the amplification of the cps2j gene coding for the capsule of s. suis serotypes 2 and 1/2. an internal control was constructed and added in this test to monitor the efficiency of amplification in each reaction. to evaluate the specificity of the test, 31 strains of other bacterial species related to s. suis or is ...200415243078
characterization of plasmid-mediated apha-3 kanamycin resistance in campylobacter jejuni.a total of 254 isolates of campylobacter jejuni and three isolates of campylobacter coli, isolated from sweden, canada, and egypt, were screened for kanamycin resistance. eight strains of c. jejuni contained large plasmids that carried the apha-3 kanamycin-resistance marker. in six plasmids, the apha-3 gene was located downstream of an apparent insertion sequence, designated is607*, which showed a considerable similarity to is607, characterized on the chromosome of some helicobacter pylori strai ...200415256024
campylobacter colonization of sibling turkey flocks reared under different management conditions.uncertainty exists concerning the key factors contributing to campylobacter colonization of poultry, especially the possible role of vertical transmission from breeder hens to young birds. a longitudinal study of campylobacter colonization was performed in two sibling pairs of turkey flocks (four flocks total). each pair of sibling flocks shared breeder hen populations and was obtained from the same hatchery. one flock of each pair was grown on a commercial farm, and the other was grown in an in ...200415270502
campylobacter prevalence in lactating dairy cows in the united states.the objective of the present study was to determine the prevalence of intestinal campylobacter in lactating dairy cows from various regions of the united states. participating commercial dairy farms were chosen at random and were part of a national survey to determine e. coli o157:h7 and salmonella prevalence in dairy cows. farms had no previous history of campylobacter problems. fecal samples were collected rectally from 720 cows on farms in the northeast (four farms), in the desert southwest ( ...200415270504
a real-time multiplexed pcr assay for rapid detection and differentiation of campylobacter jejuni and campylobacter coli.campylobacter species are the leading agents of bacterial gastroenteritis worldwide. c. jejuni and c. coli together are responsible for more than 95% of all cases of campylobacter-induced diarrheal disease in the united states. detection of campylobacteria in clinical samples by conventional culture is problematic and slow due to their complex taxonomy, fastidious growth requirements, and biochemical inertness. the current study describes a rapid, sensitive, and specific real-time polymerase cha ...200415271389
helicobacter pylori induces apoptosis of human monocytes but not monocyte-derived dendritic cells: role of the cag pathogenicity island.monocytes are circulating precursors of the dendritic cell subset, professional antigen-presenting cells with a unique ability to initiate the innate and adaptive immune response. in this study, we have investigated the effects of wild-type helicobacter pylori strains and their isogenic mutants with mutations in known bacterial virulence factors on monocytes and monocyte-derived dendritic cells. we show that h. pylori strains induce apoptosis of human monocytes by a mechanism that is dependent o ...200415271906
occurrence of campylobacter in retail foods in ireland.a surveillance study was carried out to determine the prevalence of campylobacter in a range of retail foods purchased in three irish cities over a 20-month period between march 2001 and october 2002. in total 2391 food samples were analysed during this period. campylobacter was isolated from 444 raw chicken (49.9%), 33 turkey (37.5%) and 11 duck samples (45.8%). lower isolation rates of 7/221 (3.2%), 10/197 (5.1%) and 31/262 (11.8%) were observed for raw beef, pork and lamb, respectively. one s ...200415282123
the pattern and kinetics of substrate metabolism of campylobacter jejuni and campylobacter coli.the main aim was to investigate the patterns and kinetics of substrate oxidation by campylobacter jejuni and c. coli.200415287872
role of an inducible single-domain hemoglobin in mediating resistance to nitric oxide and nitrosative stress in campylobacter jejuni and campylobacter coli.campylobacter jejuni expresses two hemoglobins, each of which exhibits a heme pocket and structural signatures in common with vertebrate and plant globins. one of these, designated cgb, is homologous to vgb from vitreoscilla stercoraria and does not possess the reductase domain seen in the flavohemoglobins. a cgb-deficient mutant of c. jejuni was hypersensitive to nitrosating agents (s-nitrosoglutathione [gsno] or sodium nitroprusside) and a nitric oxide-releasing compound (spermine nonoate). th ...200415292134
antimicrobial susceptibilities of campylobacter isolated from food-producing animals on farms (1999-2001): results from the japanese veterinary antimicrobial resistance monitoring monitoring of antimicrobial resistance in campylobacter isolated from food-producing animals on farms was performed in japan. a total of 468 campylobacter isolates were obtained during the period from june 1999 to march 2001. campylobacter species showed high frequencies of resistance to oxytetracycline and dihydrostreptomycin. the frequencies of resistance in campylobacter coli to aminoglycosides, macrolides, tetracycline and quinolones were higher than those in campylobacter jejuni ...200415325430
antigenicity of the campylobacter coli cjaa protein produced by escherichia coli.immunogenic c. coli cjaa protein is a candidate for a chicken anti-campylobacter subunit vaccine. in order to enhance its immunogenicity an antigenic determinant of the cjaa protein was identified. thereafter, two copies of the antigenic epitope were cloned in tandem directly or with a flexible hinge between them. all experiments documented that the cjaa protein contained not only linear antigenic epitope/s but also conformational ones.200415330269
use of midi-fatty acid methyl ester analysis to monitor the transmission of campylobacter during commercial poultry processing.the presence of campylobacter spp. on broiler carcasses and in scald water taken from a commercial poultry processing facility was monitored on a monthly basis from january through june. campylobacter agar, blaser, was used to enumerate campylobacter in water samples from a multiple-tank scalder; on prescalded, picked, eviscerated, and chilled carcasses; and on processed carcasses stored at 4 degrees c for 7 or 14 days. the midi sherlock microbial identification system was used to identify campy ...200415330523
species identification by genotyping and determination of antibiotic resistance in campylobacter jejuni and campylobacter coli from humans and chickens in sweden.campylobacter is today the most common cause of human bacterial enteritis in sweden, as well as in most other industrialized countries. common sources of infection are undercooked chicken meat, unpasteurized milk and contaminated drinking water. one aim with our present study was to identify the species campylobacter jejuni and campylobacter coli strains from humans and chickens using a polymerase chain reaction/restriction enzyme analysis (pcr/rea) method, as well as traditional hippurate hydro ...200415364471
use of culture, pcr analysis, and dna microarrays for detection of campylobacter jejuni and campylobacter coli from chicken feces.a dna microarray for detection of campylobacter spp. was recently developed and applied to detect campylobacter spp. directly from chicken feces. sixty-five pooled chicken cloacal swab samples from 650 individual broiler chickens were included in the study. the results of campylobacter sp. detection obtained with dna microarrays were compared to those obtained by conventional culture and gel electrophoresis. by conventional culture, 60% of the samples were positive for either campylobacter jejun ...200415364980
campylobacter, from obscurity to celebrity.after its successful isolation from stools in the 1970s, campylobacter jejuni has rapidly become the most commonly recognised cause of bacterial gastroenteritis in man. reported cases of human campylobacteriosis represent only a small fraction of the actual number. in industrialised countries, the incidence of c. jejuni/campylobacter coli infections peaks during infancy, and again in young adults aged 15-44 years. acute self-limited gastrointestinal illness, characterised by diarrhoea, fever and ...200415373879
a european survey of antimicrobial susceptibility among zoonotic and commensal bacteria isolated from food-producing study antimicrobial resistance in zoonotic bacteria isolated from food animals in different countries using uniform methodology.200415375107
nucleotide sequences and comparison of two large conjugative plasmids from different campylobacter species.two large tetracycline resistance (tcr) plasmids have been completely sequenced, the ptet plasmid (45.2 kb) from campylobacter jejuni strain 81-176 and a plasmid pcc31 (44.7 kb) from campylobacter coli strain cc31 that was isolated from a human case of severe gastroenteritis in the uk. both plasmids are mosaic in structure, having homologues of genes found in a variety of different commensal and pathogenic bacteria, but nevertheless, showed striking similarities in dna sequence and overall gene ...200415470128
swimming and campylobacter infections.a matched case-control study was conducted to study risk factors for domestically acquired sporadic campylobacter infections in finland. swimming in natural sources of water was a novel risk factor. eating undercooked meat and drinking dug-well water were also independent risk factors for campylobacter infection.200415496253
antimicrobial resistance of campylobacter jejuni and campylobacter coli isolates in japan. 200415499812
frequency and spatial distribution of environmental campylobacter spp.humans are exposed to campylobacter spp. in a range of sources via both food and environmental pathways. for this study, we explored the frequency and distribution of thermophilic campylobacter spp. in a 10- by 10-km square rural area of cheshire, united kingdom. the area contains approximately 70, mainly dairy, farms and is used extensively for outdoor recreational activities. campylobacter spp. were isolated from a range of environmental samples by use of a systematic sampling grid. livestock ...200415528512
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