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antibiotic resistance in campylobacter: emergence, transmission and persistence.campylobacter is a leading foodborne bacterial pathogen, which causes gastroenteritis in humans. this pathogenic organism is increasingly resistant to antibiotics, especially fluoroquinolones and macrolides, which are the most frequently used antimicrobials for the treatment of campylobacteriosis when clinical therapy is warranted. as a zoonotic pathogen, campylobacter has a broad animal reservoir and infects humans via contaminated food, water or milk. antibiotic usage in both animal agricultur ...200919257846
attribution of campylobacter infections in northeast scotland to specific sources by use of multilocus sequence typing.we show that a higher incidence of campylobacteriosis is found in young children (age, <5 years) living in rural, compared with urban, areas. association of this difference with particular animal sources was evaluated using multilocus sequence typing. this evaluation was achieved by comparing campylobacter isolates originating from these children, retail poultry, and a range of animal sources by use of source attribution and phylogenetic analysis methods. the results indicate that chicken is a m ...200919265482
campylobacter genotypes from food animals, environmental sources and clinical disease in scotland 2005/6.a nationwide multi-locus sequence typing (mlst) survey was implemented to analyze patterns of host association among campylobacter jejuni and campylobacter coli isolates from clinical disease in scotland (july 2005-september 2006), food animals (chickens, cattle, sheep, pigs and turkey), non-food animals (wild birds) and the environment. sequence types (sts) were determined for 5247 clinical isolates and 999 from potential disease sources (augmented with 2420 published sts). certain sts were ove ...200919269051
campylobacter genotyping to determine the source of human infection.campylobacter species cause a high proportion of bacterial gastroenteritis cases and are a significant burden on health care systems and economies worldwide; however, the relative contributions of the various possible sources of infection in humans are unclear.200919275496
the cmp-legionaminic acid pathway in campylobacter: biosynthesis involving novel gdp-linked precursors.the sialic acid-like sugar 5,7-diacetamido-3,5,7,9-tetradeoxy-d-glycero-d-galacto-nonulosonic acid, or legion-aminic acid, is found as a virulence-associated cell-surface glycoconjugate in the gram-negative bacteria legionella pneumophila and campylobacter coli. l. pneumophila serogroup 1 strains, causative agents of legionnaire's disease, contain an alpha2,4-linked homopolymer of legionaminic acid within their lipopolysaccharide o-chains, whereas the gastrointestinal pathogen c. coli modifies i ...200919282391
molecular epidemiology and characterization of campylobacter spp. isolated from wild bird populations in northern england.campylobacter infections have been reported at prevalences ranging from 2 to 50% in a range of wild bird species, although there have been few studies that have investigated the molecular epidemiology of campylobacter spp. consequently, whether wild birds are a source of infection in humans or domestic livestock or are mainly recipients of domestic animal strains and whether separate cycles of infection occur remain unknown. to address these questions, serial cross-sectional surveys of wild bird ...200919286781
regulation of superoxide dismutase (sod) genes by sara in staphylococcus aureus.the scavenging of reactive oxygen species (ros) within cells is regulated by several interacting factors, including transcriptional regulators. involvement of sara family genes in the regulation of proteins involved in the scavenging of ros is largely unknown. in this report, we show that under aerobic conditions, the levels of sodm and soda transcription, in particular the sodm transcript, are markedly enhanced in the sara mutant among the tested sara family mutants. increased levels of sod exp ...200919286803
independent evolution of neurotoxin and flagellar genetic loci in proteolytic clostridium botulinum.proteolytic clostridium botulinum is the causative agent of botulism, a severe neuroparalytic illness. given the severity of botulism, surprisingly little is known of the population structure, biology, phylogeny or evolution of c. botulinum. the recent determination of the genome sequence of c. botulinum has allowed comparative genomic indexing using a dna microarray.200919298644
campylobacter jejuni glycosylation island important in cell charge, legionaminic acid biosynthesis, and colonization of chickens.previously, we identified five genes (cj1321 to cj1326, of which cj1325 and cj1326 are a single gene) in the o-linked flagellin glycosylation island that are highly prevalent in campylobacter jejuni isolates from chickens. we report mutagenesis, functional, and structural data to confirm that this locus, and cj1324 in particular, has a significant contributory role in the colonization of chickens by c. jejuni. a motile deltacj1324 mutant with intact flagella was considerably less hydrophobic and ...200919307210
incidence and risk factors for community-acquired acute gastroenteritis in north-west germany in 2004.in developed countries, acute gastroenteritis (age) is a major source of morbidity. however, only a few studies have estimated its incidence and the associated medical burden. this population-based study determined the incidence of community-acquired age patients seeking medical care and the relative role of various pathogens. stool samples from patients with age presenting to a general practitioner (gp), pediatrician, or specialist in internal medicine for that reason were screened for various ...200919319582
survival at refrigeration and freezing temperatures of campylobacter coli and campylobacter jejuni on chicken skin applied as axenic and mixed inoculums.campylobacter is considered to be the most common cause of bacterial diarrhoeal illness in the developed world. many cases are thought to be acquired from consumption of undercooked poultry. the aim of this study was to compare the effect of the rate of cooling on the survival, at 4 degrees c and -20 degrees c, of campylobacter coli and campylobacter jejuni strains, inoculated on chicken skin from axenic culture or as mixed inoculums. strains chilled in a domestic refrigerator varied in their to ...200919324444
dna mimics for the rapid identification of microorganisms by fluorescence in situ hybridization (fish).fluorescence in situ hybridization (fish) is a well-established technique that is used for a variety of purposes, ranging from pathogen detection in clinical diagnostics to the determination of chromosomal stability in stem cell research. the key step of fish involves the detection of a nucleic acid region and as such, dna molecules have typically been used to probe for the sequences of interest. however, since the turn of the century, an increasing number of laboratories have started to move on ...200819325728
temporal patterns and risk factors for escherichia coli o157 and campylobacter spp, in young cattle.escherichia coli o157 and campylobacter jejuni and campylobacter coli are zoonotic pathogens originating from farm animals. cattle are the main reservoir for e. coli o157 and also contribute to human cases of campylobacteriosis through contaminated milk, direct contact, and environmental contamination. thirty groups of young cattle on 30 farms were observed for 7 months and sampled on 4 to 6 separate occasions for e. coli o157 and c. jejuni/coli to characterize shedding patterns and identify ris ...200919343935
comparative studies of campylobacter jejuni genomic diversity reveal the importance of core and dispensable genes in the biology of this enigmatic food-borne pathogen.mlst, dna microarrays, and genome sequencing has allowed for a greater understanding of the metabolic capacity and epidemiology of campylobacter jejuni. while strain-specific genes may provide an isolate a selective advantage in environments and contribute to the organism's pathogenicity, recent work indicates that c. jejuni pathogenicity is dictated by variations in the nucleotide sequence of core genes. challenges facing c. jejuni researchers include determining (a) the degree to which genomic ...200919346123
campylobacter colonization of the turkey intestine in the context of microbial community development.patterns of microbial community dynamics in the turkey intestine were examined. every week of the 18-week production cycle, cecal bacterial communities and campylobacter loads were examined from five birds for each of two flocks. molecular fingerprinting via the automated ribosomal intergenic spacer analysis (arisa) and terminal restriction fragment length polymorphism (t-rflp) of the cecal samples revealed that microbial communities changed in a time-dependent manner, and during both trials the ...200919346343
a longitudinal study of campylobacter distribution in a turkey production chain.campylobacter is the most common cause of bacterial enteritis worldwide. handling and eating of contaminated poultry meat has considered as one of the risk factors for human campylobacteriosis. campylobacter contamination can occur at all stages of a poultry production cycle. the objective of this study was to determine the occurrence of campylobacter during a complete turkey production cycle which lasts for 1,5 years of time. for detection of campylobacter, a conventional culture method was com ...200919348687
functional characterization of excision repair and reca-dependent recombinational dna repair in campylobacter jejuni.the presence and functionality of dna repair mechanisms in campylobacter jejuni are largely unknown. in silico analysis of the complete translated genome of c. jejuni nctc 11168 suggests the presence of genes involved in methyl-directed mismatch repair (mmr), nucleotide excision repair, base excision repair (ber), and recombinational repair. to assess the functionality of these putative repair mechanisms in c. jejuni, muts, uvrb, ung, and reca knockout mutants were constructed and analyzed for t ...200919376866
[evaluation of usefulness of commercial recomwell campylobacter enzyme--linked immunosorbent assays for routine serodiagnosis of campylobacter jejuni and campylobacter coli infections].the commercially available enzyme-linked immunosorbent assays (elisa recomwell campylobacter) from mikrogen was evaluated for the diagnosis of campylobacter jejuni and campylobacter coli infections. serum samples from 20 healthy controls, 44 persons with symptoms of primary campylobacter infection and 24 serum samples from patients with yersinia enterocolitica or salmonella infections were tested. this elisa assay detects iga and igg antibodies against three recombinant antigens of the campyloba ...200819382600
a single nucleotide change affects fur-dependent regulation of sodb in h. pylori.helicobacter pylori is a significant human pathogen that has adapted to survive the many stresses found within the gastric environment. superoxide dismutase (sodb) is an important factor that helps h. pylori combat oxidative stress. sodb was previously shown to be repressed by the ferric uptake regulator (fur) in the absence of iron (apo-fur regulation) [1]. herein, we show that apo regulation is not fully conserved among all strains of h. pylori. apo-fur dependent changes in sodb expression are ...200919399190
campylobacter jejuni in penguins, antarctica. 200919402996
novel campylobacter lari-like bacteria from humans and molluscs: description of campylobacter peloridis sp. nov., campylobacter lari subsp. concheus subsp. nov. and campylobacter lari subsp. lari subsp. nov.a polyphasic study was undertaken to clarify the taxonomic position of campylobacter lari-like strains isolated from shellfish and humans. the diversity within the strain collection was initially screened by means of fluorescent amplified fragment length polymorphism analysis and whole-cell protein electrophoresis, revealing the existence of two clusters distinct from c. lari and other campylobacter species. the divergence of these clusters was confirmed by phenotypic analysis and by 16s rrna an ...200919406805
drug efflux pump deficiency and drug target resistance masking in growing bacteria.recent experiments have shown that drug efflux pump deficiency not only increases the susceptibility of pathogens to antibiotics, but also seems to "mask" the effects of mutations, that decrease the affinities of drugs to their intracellular targets, on the growth rates of drug-exposed bacteria. that is, in the presence of drugs, the growth rates of drug-exposed wt and target mutated strains are the same in a drug efflux pump deficient background, but the mutants grow faster than wt in a drug ef ...200919416855
population structure of streptococcus oralis.streptococcus oralis is a member of the normal human oral microbiota, capable of opportunistic pathogenicity; like related oral streptococci, it exhibits appreciable phenotypic and genetic variation. a multilocus sequence typing (mlst) scheme for s. oralis was developed and the resultant data analysed to examine the population structure of the species. analysis of 113 isolates, confirmed as belonging to the s. oralis/mitis group by 16s rrna gene sequencing, characterized the population as highly ...200919423627
pyrazolopyrimidinediones are selective agents for helicobacter pylori that suppress growth through inhibition of glutamate racemase (muri).pyrazolopyrimidinediones are a novel series of compounds that inhibit growth of helicobacter pylori specifically. using a variety of methods, advanced analogues were shown to suppress the growth of h. pylori through the inhibition of glutamate racemase, an essential enzyme in peptidoglycan biosynthesis. the high degree of selectivity of the series for h. pylori makes these compounds attractive candidates for novel h. pylori-selective therapy.200919433553
application of a group ii campylobacter bacteriophage to reduce strains of campylobacter jejuni and campylobacter coli colonizing broiler chickens.members of the genus campylobacter are frequently responsible for human enteric disease worldwide. persistent campylobacter contamination of poultry meat is a common problem that represents a significant food safety risk through the consumption of undercooked poultry meat or through cross-contamination of other foods during the preparation of poultry. bacteriophage therapy is one possible means by which this colonization of poultry could be controlled, thus limiting the entry of campylobacter in ...200919435220
production and characterization of a monoclonal antibody to campylobacter jejuni.campylobacter species are a group of spiral-shaped bacteria that can cause disease in humans and animals. we developed a high-affinity monoclonal antibody (mab) probe that recognizes campylobacter jejuni cells. cell suspensions grown under microaerobic conditions at 42 degrees c for 20 h on bolton agar plates with lysed horse blood were used as live and heat-killed preparations, centrifuged at 8,000 x g for 20 min, and resuspended in carbonate buffer (ph 9.6) for coating on the enzyme-linked imm ...200919435241
transmission of foodborne zoonotic pathogens to riparian areas by grazing sheep.the objective of this study was to determine if sheep grazing near riparian areas on pasture in ontario are an important risk factor for the contamination of water with specific foodborne pathogens. ten ontario sheep farms were visited weekly for 12 wk during the summer of 2005. samples of feces, soil, and water were collected and analyzed for the presence of escherichia coli o157:h7, salmonella spp., campylobacter jejuni and c. coli, and yersinia enterocolitica, by bacteriological identificatio ...200919436581
inaccuracy of routine susceptibility tests for detection of erythromycin resistance of campylobacter jejuni and campylobacter coli.in the netherlands, both an increase in and regional differences in erythromycin resistance of campylobacter jejuni and campylobacter coli have been reported. to determine the accuracy of routine tests for erythromycin resistance, 48 erythromycin-resistant isolates from various laboratories that participate in the dutch surveillance of campylobacter infections were reinvestigated. initial susceptibility testing for erythromycin had been performed by disk diffusion in six and mic-based methods in ...201019438640
multiplex strategy for multilocus sequence typing, fla typing, and genetic determination of antimicrobial resistance of campylobacter jejuni and campylobacter coli isolates collected in switzerland.we present an optimized multilocus sequence typing (mlst) scheme with universal primer sets for amplifying and sequencing the seven target genes of campylobacter jejuni and campylobacter coli. typing was expanded by sequence determination of the genes flaa and flab using optimized primer sets. this approach is compatible with the mlst and flaa schemes used in the pubmlst database and results in an additional typing method using the flab gene sequence. an identification module based on the 16s rr ...200919439549
occurrence and enumeration of campylobacter spp. during the processing of chilean broilers.thermotolerant campylobacter is among the more prevalent bacterial pathogens that cause foodborne diseases. this study aimed at evaluating the occurrence of thermotolerant campylobacter contamination in chicken carcasses and processing plant stations (chilling water, scalding water, defeathering machinery, evisceration machine, and transport crates) in two of the chilean main slaughterhouses. in addition, the isolation rates of thermotolerant campylobacter during evisceration and following chill ...200919445680
survival rate of thermotolerant campylobacter on poultry meat during microwave heating.survival rates of campylobacterjejuni atcc 33 291, campylobacter jejuni pzh 38 and campylobacter coli atcc 43 478 in leg quarters (ca 330 g) of chicken broilers after microwave heating (480 and 760 watt) for 2, 4, 6, 8 and 10 minutes were determined. heating the meat in a microwave oven (moulinex, type dialog cook) at 480 watts caused a gradual decrease in the number of cells of the studied bacterial strains to total inactivation after 8-10 minutes of heating. increasing the heating power to 760 ...200919459438
the helicobacter pylori anti-sigma factor flgm is predominantly cytoplasmic and cooperates with the flagellar basal body protein flha.helicobacter pylori requires flagellar motility and orientation to persist actively in its habitat. a particular feature of flagella in most helicobacter species including h. pylori is a membraneous flagellar sheath. the anti-sigma factor flgm of h. pylori is unusual, since it lacks an n-terminal domain present in other flgm homologs, e.g., flgm of salmonella spp., whose regulatory function is intimately coupled to its secretion through the flagellar type iii secretion system. the aim of the pre ...200919465658
beta-lactamase-mediated beta-lactam resistance in campylobacter species: prevalence of cj0299 (bla oxa-61) and evidence for a novel beta-lactamase in c. jejuni.fifty-two percent of 1,288 poultry isolates of campylobacters were ampicillin resistant, and resistance was more common among campylobacter coli isolates (67.4%) than among campylobacter jejuni isolates (47.5%). production of beta-lactamase was typically associated with resistance to ampicillin, amoxicillin (amoxicilline), penicillin, and ticarcillin. regardless of beta-lactamase production, all isolates were resistant to piperacillin (mics >or= 256 microg/ml), and most were resistant to carbeni ...200919506058
[evaluation of genotypic and phenotypic methods for the differentiation of campylobacter jejuni and campylobacter coli clinical isolates from poland. i. biotyping, resistance pattern, plasmid analysis, restriction enzyme analysis of plasmid].a total of 128 clinical isolates of c. jejuni and 17 clinical isolates of c. coli were characterized by their plasmid profiles, susceptibility to six antimicrobial agents and the lior biotypes. we also analyzed seven isolates from three c. jejuni family outbreaks and three isolates from one c. coli family outbreak. plasmids were found in 47 c. jejuni (36.7%) and 3 c. coli (17.6%) isolates. the sizes of plasmids detected ranged from about 3.3 to 89 kb. the majority of campylobacter isolates (n = ...200919517815
[evaluation of genotypic and phenotypic methods for the differentiation of campylobacter jejuni and campylobacter coli clinical isolates from poland. ii. pfge, eric-pcr, pcr-flaa-rflp and mlst].campylobacter jejuni and campylobacter coli are leading cause of bacterial gastroenteritis in many developed countries. we compared pulsed-field gel electrophoresis (pfge), enterobacterial repetitive intergenic consensus (eric-pcr) and restriction fragment length polymorphisms of the flagellin gene (pcr-flaa-rflp) for distinguishing 128 c. jejuni isolates and 17 c. coli clinical isolates isolated between 2006 and 2007 in poland. we also analysed seven isolates from three c. jejuni family outbrea ...200919517816
the dual-functioning fumarate reductase is the sole succinate:quinone reductase in campylobacter jejuni and is required for full host colonization.campylobacter jejuni encodes all the enzymes necessary for a complete oxidative tricarboxylic acid (tca) cycle. because of its inability to utilize glucose, c. jejuni relies exclusively on amino acids as the source of reduced carbon, and they are incorporated into central carbon metabolism. the oxidation of succinate to fumarate is a key step in the oxidative tca cycle. c. jejuni encodes enzymes annotated as a fumarate reductase (cj0408 to cj0410) and a succinate dehydrogenase (cj0437 to cj0439) ...200919525346
prevalence of thermotolerant campylobacter in partridges (perdix perdix).to estimate the prevalence of thermotolerant campylobacter spp. in commercially reared partridges (perdix perdix) in southern italy.200919552770
campylobacter coli naturally resistant to elevated levels of gentamicin as a marker strain in poultry research.campylobacter inoculation studies are limited without a suitable marker strain. the lurpose of this study was to screen campylobacter strains (n=2073) obtained from poultry carcass rinses through the centers for disease control and prevention's national antimicrobial resistant monitoring system for resistance to gentamicin and evaluate one strain's efficacy as a marker. a c. coli strain was found resistant to gentamicin at >32 microg/ml. gentamicin was incorporated into media (campy-cefex agar, ...200919610342
genomic insights into the convergence and pathogenicity factors of campylobacter jejuni and campylobacter coli species.whether or not bacteria form coherent evolutionary groups via means of genetic exchange and, hence, elicit distinct species boundaries remains an unsettled issue. a recent report implied that not only may the former be true but also, in fact, the clearly distinct campylobacter jejuni and campylobacter coli species may be converging as a consequence of increased interspecies gene flow fostered, presumably, by the recent invasion of an overlapping ecological niche (s. k. sheppard, n. d. mccarthy, ...200919617370
prokaryotic protein glycosylation is rapidly expanding from "curiosity" to "ubiquity". 200919621412
occurrence of salmonella, campylobacter, yersinia enterocolitica, escherichia coli o157 and listeria monocytogenes in swine.the objective of this study was to investigate the occurrence of major bacterial foodborne pathogens in swine. in total, 359 samples from manure storage tanks (91) and fresh pooled faeces (268) obtained from finisher (110), sows (78) and weanlings (80) were collected and tested. campylobacter, salmonella, yersinia enterocolitica, escherichia coli o157 and listeria monocytogenes were isolated from 36.5%, 31.5%, 5.8%, 3.3% and 3.3% of samples respectively. all e. coli o157 isolates found on 10 far ...201019638163
susceptibility of campylobacter jejuni and campylobacter coli isolated from animals and humans to ciprofloxacin.fifty five thermophilic campylobacter spp. strains were isolated from the caecum of broilers, cecum and colon of pigs and from human faeces. the strains were identified as campylobacter jejuni and campylobacter coli. the more prevalent species in humans and broilers was campylobacter jejuni, and in pigs campylobacter coli. in the framework of this study, sensitivity to ciprofloxacin in isolated strains of campylobacter jejuni and campylobacter coli was tested by e-test. resistant to ciprofloxaci ...200919645360
the response of campylobacter jejuni to low temperature differs from that of escherichia coli.human infection with campylobacter jejuni is often associated with the consumption of foods that have been exposed to both chilling and high temperatures. despite the public health importance of this pathogen, little is known about the effects of cold exposure on its ability to survive a subsequent heat challenge. this work examined the effect of rapid exposure to chilling, as would occur in poultry processing, on the heat resistance at 56 degrees c of two c. jejuni strains, 11168 and 2097e48, a ...200919648365
novel clonal complexes with an unknown animal reservoir dominate campylobacter jejuni isolates from river water in new zealand.campylobacter jejuni is widely distributed in the environment, and river water has been shown to carry high levels of the organism. in this study, 244 c. jejuni isolates from three river catchment areas in new zealand were characterized using multilocus sequence typing. forty-nine of the 88 sequence types identified were new. the most common sequence types identified were st-2381 (30 isolates), st-45 (25 isolates), and st-1225 (23 isolates). the majority of the sequence types identified in the r ...200919648367
amoxicillin therapy of poultry flocks: effect upon the selection of amoxicillin-resistant commensal campylobacter spp.the aim of this study was to investigate the effect of amoxicillin therapy of poultry flocks upon the persistence of commensal campylobacter spp. and the incidence of antibiotic resistance.200919656785
campylobacter coli prosthetic hip infection associated with ingestion of contaminated oysters.this report describes the first reported case of a prosthetic hip joint infection due to campylobacter coli. the infection presumably resulted from ingestion of contaminated raw oysters. issues regarding original smear interpretation, culture isolation, and susceptibility testing are presented.200919656982
rapid identification of bacterial pathogens using a pcr- and microarray-based assay.during the course of a bacterial infection, the rapid identification of the causative agent(s) is necessary for the determination of effective treatment options. we have developed a method based on a modified broad-range pcr and an oligonucleotide microarray for the simultaneous detection and identification of 12 bacterial pathogens at the species level. the broad-range pcr primer mixture was designed using conserved regions of the bacterial topoisomerase genes gyrb and pare. the primer design a ...200919664269
efflux-mediated drug resistance in bacteria: an update.drug efflux pumps play a key role in drug resistance and also serve other functions in bacteria. there has been a growing list of multidrug and drug-specific efflux pumps characterized from bacteria of human, animal, plant and environmental origins. these pumps are mostly encoded on the chromosome, although they can also be plasmid-encoded. a previous article in this journal provided a comprehensive review regarding efflux-mediated drug resistance in bacteria. in the past 5 years, significant pr ...200919678712
spatiotemporal homogeneity of campylobacter subtypes from cattle and sheep across northeastern and southwestern scotland.source attribution using molecular subtypes has implicated cattle and sheep as sources of human campylobacter infection. whether the campylobacter subtypes associated with cattle and sheep vary spatiotemporally remains poorly known, especially at national levels. here we describe spatiotemporal patterns of prevalence, bacterial enumeration, and subtype composition in campylobacter isolates from cattle and sheep feces from northeastern (63 farms, 414 samples) and southwestern (71 farms, 449 sampl ...200919700557
demonstration of persistent strains of campylobacter jejuni within broiler farms over a 1-year period in lithuania.the aim of the study was to investigate the flock prevalence of campylobacter jejuni and campylobacter coli in broiler farms in lithuania and to identify possible persistent strains of camp. jejuni using amplified fragment length polymorphism (aflp) typing method.201019709341
thermotolerant coliforms are not a good surrogate for campylobacter spp. in environmental water.this study aimed to assess the importance of quantitatively detecting campylobacter spp. in environmental surface water. the prevalence and the quantity of campylobacter spp., thermotolerant coliforms, and escherichia coli in 2,471 samples collected weekly, over a 2-year period, from 13 rivers and 12 streams in the eastern townships, québec, canada, were determined. overall, 1,071 (43%), 1,481 (60%), and 1,463 (59%) samples were positive for campylobacter spp., thermotolerant coliforms, and e. c ...200919734335
dna identification and characterization of campylobacter jejuni and campylobacter coli isolated from caecal samples of chickens in grenada.to speciate campylobacter strains from the caeca of chickens in grenada using pcr and to evaluate dna-based typing methods for the characterization of these isolates.201019735321
molecular, antigenic, and functional characteristics of ferric enterobactin receptor cfra in campylobacter jejuni.the ferric enterobactin receptor cfra not only is responsible for high-affinity iron acquisition in campylobacter jejuni but also is essential for c. jejuni colonization in animal intestines. in this study, we determined the feasibility of targeting the iron-regulated outer membrane protein cfra for immune protection against campylobacter colonization. alignment of complete cfra sequences from 15 campylobacter isolates showed that the levels of amino acid identity for cfra range from 89% to 98%. ...200919737895
genetic diversity and stability of the pora allele as a genetic marker in human campylobacter infection.the major outer-membrane protein (momp) of campylobacter jejuni and campylobacter coli, encoded by the pora gene, is extremely genetically diverse. conformational momp epitopes are important in host immunity, and variation in surface-exposed regions probably occurs as a result of positive immune selection during infection. pora diversity has been exploited in genotyping studies using highly discriminatory nucleotide sequences to identify potentially epidemiologically linked cases of human campyl ...200919744989
cost analysis and antimicrobial susceptibility testing comparing the e test and the agar dilution method in campylobacter jejuni and campylobacter coli.although numerous reports have compared the antimicrobial susceptibility of campylobacter spp., controversy still exists about the use of the e test as an alternative to the agar dilution method suggested by the clinical and laboratory standards institute. mics of 8 antimicrobials were determined using the e test and agar dilution methods for 103 campylobacter jejuni and campylobacter coli isolates from fresh chicken randomly purchased from stores in 3 southern ontario counties. overall, 72.6% o ...200919748428
functional characterization of flagellin glycosylation in campylobacter jejuni 81-176.the major flagellin of campylobacter jejuni strain 81-176, flaa, has been shown to be glycosylated at 19 serine or threonine sites, and this glycosylation is required for flagellar filament formation. some enzymatic components of the glycosylation machinery of c. jejuni 81-176 are localized to the poles of the cell in an flhf-independent manner. flagellin glycosylation could be detected in flagellar mutants at multiple levels of the regulatory hierarchy, indicating that glycosylation occurs inde ...200919749047
mouse intestine colonization ability of campylobacter coli strains.campylobacter coli is an etiological agent of gastrointestinal and extraintestinal infections in man and animals, and can be found as a commensal in gastrointestinal tract of animals. in this study, we aimed to determine differences among c coli strains in colonization of the intestinal tract of mice. seven c coli strains isolated from diarrheic patients, asymptomatic hosts and chicken carcasses were used for this study. each strain was inoculated with 0.1 ml of a bacterial suspension (3 x 10(8) ...200919753795
diversity of campylobacter jejuni and campylobacter coli genotypes from human and animal sources from rio de janeiro, brazil.to compare the genotypes of campylobacter jejuni and campylobacter coli isolates of human and animal origin collected in rio de janeiro city, 30 c. jejuni and 35 c. coli isolates from animal sources (n=45) and human patients with gastroenteritis (n=20) were genotyped by pcr-based techniques, namely random amplified polymorphic dna (rapd-pcr) and enterobacterial repetitive intergenic consensus sequence (eric-pcr). rapd-pcr identified 50 types and eric-pcr identified 22 genotypes, among the 65 cam ...201019765787
functional analysis of the helicobacter pylori flagellar switch proteins.helicobacter pylori uses flagellum-mediated chemotaxis to promote infection. bacterial flagella change rotational direction by changing the state of the flagellar motor via a subcomplex referred to as the switch. intriguingly, the h. pylori genome encodes four switch complex proteins, flim, flin, fliy, and flig, instead of the more typical three of escherichia coli or bacillus subtilis. our goal was to examine whether and how all four switch proteins participate in flagellation. previous work de ...200919767432
prevalence of campylobacter spp. in raw retail poultry on sale in northern ireland.a year-long survey of fresh, retail poultry products on sale in northern ireland was undertaken to define the prevalence of campylobacter spp. by using protocols based on iso (standard) 10272-1:2006. incubation at 37 and 42 degrees c was undertaken to increase the diversity of isolates obtained. overall, 652 isolates were identified as campylobacter spp. by using pcr and amplified fragment length polymorphic typing. phenotyping wrongly identified 21% of isolates. prevalences of campylobacter fou ...200919777882
comparison between the biofilm initiation of campylobacter jejuni and campylobacter coli strains to an inert surface using biofilm ring test.the adhesion to an inert surface (the first step of biofilm formation) of the two main pathogenic campylobacter species, campylobacter jejuni and campylobacter coli, isolated from diverse origins, was compared.201019796124
long-term survival of campylobacter jejuni at low temperatures is dependent on polynucleotide phosphorylase activity.campylobacter jejuni is a leading cause of bacterial gastroenteritis worldwide. infection generally occurs after ingestion of contaminated poultry products, usually conserved at low temperatures. the mechanisms promoting survival of c. jejuni in the cold remain poorly understood despite several investigations. the present study provides insight into the survival mechanism by establishing the involvement of polynucleotide phosphorylase (pnpase), a 3'-5' exoribonuclease with multiple biological fu ...200919801468
study of cytolethal distending toxin (cdt) in campylobacter coli using a multiplex polymerase chain reaction assay and its distribution among clinical and food strains.from a collection of 242 food isolates of campylobacter spp. 72 were identified as campylobacter jejuni and 170 as campylobacter coli and of 112 isolates from clinical sources, 92 were identified as c. jejuni and 20 as c. coli. the results for food isolates were in contrast to other reported identifications. twenty c. coli strains from clinical cases of campylobacter that occurred in portugal and 170 isolated from poultry products were examined for the presence of cytolethal distending toxin (cd ...201019821742
development and evaluation of internal amplification controls for use in a real-time duplex pcr assay for detection of campylobacter coli and campylobacter jejuni.a common problem of both conventional and real-time pcr assays is failure of dna amplification due to the presence of inhibitory substances in samples. in view of this, our aim was to develop and evaluate internal amplification controls (iacs) for use with an existing duplex real-time pcr assay for campylobacter coli and campylobacter jejuni. both competitive and non-competitive iacs were developed and evaluated. the competitive approach involved a dna fragment of the coding region of the fish v ...201019833779
campylobacter species occurrence within internal organs and tissues of commercial caged leghorn laying hens.campylobacter spp. are frequently present in the intestinal tract and internal tissues of broiler breeder and broiler chickens. campylobacter spp. ecology in commercial leghorn laying hens has not been extensively studied. the objectives of the current study were to determine 1) campylobacter spp. presence in the reproductive tract, lymphoid organs, liver-gallbladder, and ceca of commercial leghorn laying hens; 2) species of campylobacter present; and 3) antimicrobial resistance pattern of campy ...200919834099
characterization of the oxidative stress stimulon and perr regulon of campylobacter jejuni.during gut colonization, the enteric pathogen campylobacter jejuni must surmount the toxic effects of reactive oxygen species produced by its own metabolism, the host immune system, and intestinal microflora. elucidation of c. jejuni oxidative stress defense mechanisms is critical for understanding campylobacter pathophysiology.200919835633
campylobacter excreted into the environment by animal sources: prevalence, concentration shed, and host association.an intensive study of 443 isolates of campylobacter jejuni and campylobacter coli from 2031 fecal samples excreted by animal sources including cattle, sheep, and pigs, a range of wild and domesticated avian species and pets is described. the prevalence found in the majority of animal sources ranged from 22% to 28% with poultry being highest at 41% and cats and dogs lowest (<5%). the average count excreted for each animal source was found not to be significantly different ranging from approximate ...200919839759
multiplex pcr to diagnose bloodstream infections in patients admitted from the emergency department with sepsis.sepsis is caused by a heterogeneous group of infectious etiologies. early diagnosis and the provision of appropriate antimicrobial therapy correlate with positive clinical outcomes. current microbiological techniques are limited in their diagnostic capacities and timeliness. multiplex pcr has the potential to rapidly identify bloodstream infections and fill this diagnostic gap. we identified patients from two large academic hospital emergency departments with suspected sepsis. the results of a m ...200919846634
multiplex pcr to diagnose bloodstream infections in patients admitted from the emergency department with sepsis.sepsis is caused by a heterogeneous group of infectious etiologies. early diagnosis and the provision of appropriate antimicrobial therapy correlate with positive clinical outcomes. current microbiological techniques are limited in their diagnostic capacities and timeliness. multiplex pcr has the potential to rapidly identify bloodstream infections and fill this diagnostic gap. we identified patients from two large academic hospital emergency departments with suspected sepsis. the results of a m ...200919846634
investigation of food and environmental exposures relating to the epidemiology of campylobacter coli in humans in northwest england.this study uses multilocus sequence typing (mlst) to investigate the epidemiology of campylobacter coli in a continuous study of a population in northwest england. all cases of campylobacter identified in four local authorities (government administrative boundaries) between 2003 and 2006 were identified to species level and then typed, using mlst. epidemiological information was collected for each of these cases, including food and recreational exposure variables, and the epidemiologies of c. je ...201019854914
a genomic island defines subspecies-specific virulence features of the host-adapted pathogen campylobacter fetus subsp. venerealis.the pathogen campylobacter fetus comprises two subspecies, c. fetus subsp. fetus and c. fetus subsp. venerealis. although these taxa are highly related on the genome level, they are adapted to distinct hosts and tissues. c. fetus subsp. fetus infects a diversity of hosts, including humans, and colonizes the gastrointestinal tract. in contrast, c. fetus subsp. venerealis is largely restricted to the bovine genital tract, causing epidemic abortion in these animals. in light of their close genetic ...201019897645
a genomic island defines subspecies-specific virulence features of the host-adapted pathogen campylobacter fetus subsp. venerealis.the pathogen campylobacter fetus comprises two subspecies, c. fetus subsp. fetus and c. fetus subsp. venerealis. although these taxa are highly related on the genome level, they are adapted to distinct hosts and tissues. c. fetus subsp. fetus infects a diversity of hosts, including humans, and colonizes the gastrointestinal tract. in contrast, c. fetus subsp. venerealis is largely restricted to the bovine genital tract, causing epidemic abortion in these animals. in light of their close genetic ...201019897645
efficacy of mini vidas for the detection of campylobacter spp. from retail broiler meat enriched in bolton broth, with or without the supplementation of blood.the goals of this study were to evaluate the efficacy of the mini vidas automated immunoassay chemistry system to detect campylobacter spp. from retail broiler meat enriched in bolton broth supplemented with lysed blood (b+b) or without blood (b-b), and to detect positive samples at 24 versus 48 h after enrichment. retail broiler meat was enriched and tested for campylobacter spp. with the mini vidas and with an agar plate. isolates were speciated with a multiplex pcr and typed with pulsed-field ...200919903413
development of a dna microarray to detect antimicrobial resistance genes identified in the national center for biotechnology information database.to understand the mechanisms and epidemiology of antimicrobial resistance (ar), the genetic elements responsible must be identified. due to the myriad of possible genes, a high-density genotyping technique is needed for initial screening. to achieve this, ar genes in the national center for biotechnology information genbank database were identified by their annotations and compiled into a nonredundant list of 775 genes. a dna microarray was constructed of 70mer oligonucelotide probes designed to ...201019916789
recrudescent campylobacter jejuni infection in an immunocompetent adult following experimental infection with a well-characterized organism.the recrudescence of infection with campylobacter jejuni after appropriate antibiotic treatment has not been previously reported in an immunocompetent adult. we present the complete clinical, microbiologic, and immunologic evaluation of a closely monitored healthy male with recrudescent c. jejuni infection occurring in the absence of immunodeficiency following experimental infection with a well-characterized strain. after antibiotic treatment, the initial infection was clinically cleared and mic ...201019923572
recrudescent campylobacter jejuni infection in an immunocompetent adult following experimental infection with a well-characterized organism.the recrudescence of infection with campylobacter jejuni after appropriate antibiotic treatment has not been previously reported in an immunocompetent adult. we present the complete clinical, microbiologic, and immunologic evaluation of a closely monitored healthy male with recrudescent c. jejuni infection occurring in the absence of immunodeficiency following experimental infection with a well-characterized strain. after antibiotic treatment, the initial infection was clinically cleared and mic ...201019923572
campylobacter jejuni and campylobacter coli genotyping by high-resolution melting analysis of a flaa fragment.the highly variable flagellin-encoding flaa gene has long been used for genotyping campylobacter jejuni and campylobacter coli. high-resolution melting (hrm) analysis is emerging as an efficient and robust method for discriminating dna sequence variants. the objective of this study was to apply hrm analysis to flaa-based genotyping. the initial aim was to identify a suitable flaa fragment. it was found that the pcr primers commonly used to amplify the flaa short variable repeat (svr) yielded a m ...201019933351
description and sources of contamination by campylobacter spp. of river water destined for human consumption in brittany, france.presence or absence of campylobacter spp. in water of five rivers upstream from an intake point for drinking water production was investigated, and isolates genetically compared with human, pig and poultry isolates in order to determine their source. river water and drinking water obtained from these rivers were sampled one time per month, over a period of one year, and tested for campylobacter. isolates were typed by pfge. campylobacter was not detected in treated drinking water, but 50% of the ...200919942377
species-specific identification and differentiation of arcobacter, helicobacter and campylobacter by full-spectral matrix-associated laser desorption/ionization time of flight mass spectrometry analysis.rapid and reliable identification of arcobacter and helicobacter species, and their distinction from phenotypically similar campylobacter species, has become increasingly important, since many of them are now recognized as human and/or animal pathogens. matrix-associated laser desorption/ionization-time of flight (maldi-tof) ms has been shown to be a rapid and sensitive method for characterization of micro-organisms. in this study, we therefore established a reference database of selected arcoba ...201019959629
occurrence of thermophilic campylobacter spp. contamination on vegetable farms in malaysia.the aim of the present study was to examine the prevalence of thermophilic campylobacter spp. (campylobacter jejuni and campylobacter coli) in soil, poultry manure, irrigation water, and freshly harvested vegetables from vegetable farms in malaysia. c. jejuni was detected in 30.4% and 2.7% of the soil samples, 57.1% and 0% of the manure samples, and 18.8% and 3% of the vegetable samples from farm a and farm b, respectively, when using the mpnpcr method. campylobacter spp. was not found in any of ...200919996696
genetic similarity of campylobacter isolates in humans, food, and water sources in central poland.campylobacter spp. is an important cause of gastroenteritis in humans throughout the world. however, sources of these infections are often difficult to identify. therefore, this study aimed at analyzing the genetic relatedness of campylobacter isolates from environmental and food samples as well as stool specimens of diarrheal patients obtained in a single geographic region in poland. only a few campylobacter jejuni isolates (4/18, 22%) could be assigned to one cluster, whereas the majority were ...201020001328
method for bacteriophage isolation against target campylobacter strains.poultry meat is considered a major source of campylobacter. this micro-aerobic bacterium is commonly responsible for foodborne illness. this work focuses on the isolation of campylobacter coli lytic bacteriophages (phages) against target c. coli strains.201020002571
helicobacter pylori lipopolysaccharide modification, lewis antigen expression, and gastric colonization are cholesterol-dependent.helicobacter pylori specifically takes up cholesterol and incorporates it into the bacterial membrane, yet little is currently known about cholesterol's physiological roles. we compared phenotypes and in vivo colonization ability of h. pylori grown in a defined, serum-free growth medium, f12 with 1 mg/ml albumin containing 0 to 50 mug/ml cholesterol.200920003432
the hemolytic and cytolytic activities of serratia marcescens phospholipase a (phla) depend on lysophospholipid production by phla.serratia marcescens is a gram-negative bacterium and often causes nosocomial infections. there have been few studies of the virulence factors of this bacterium. the only s. marcescens hemolytic and cytotoxic factor reported, thus far, is the hemolysin shla.200920003541
easy-to-use rapid test for direct detection of campylobacter spp. in chicken feces.human campylobacteriosis is the leading cause of acute bacterial gastroenteritis in developed countries. one important source of infection is poultry. results from the dutch campylobacter risk management and assessment project indicate that meat from broiler flocks shedding >or=7 log cfu campylobacter per g of feces poses the greatest risk of transmitting campylobacteriosis. the objective of this study was to develop a simple and rapid test that would identify chicken flocks shedding high number ...200920003729
comprehensive and rapid real-time pcr analysis of 21 foodborne outbreaks.a set of four duplex sybr green i pcr (sg-pcr) assay combined with dna extraction using qiaamp dna stool mini kit was evaluated for the detection of foodborne bacteria from 21 foodborne outbreaks. the causative pathogens were detected in almost all cases in 2 hours or less. the first run was for the detection of 8 main foodborne pathogens in 5 stool specimens within 2 hours and the second run was for the detection of other unusual suspect pathogens within a further 45 minutes. after 2 to 4 days, ...200920016673
prolonged survival of campylobacter species in bovine manure compost.the persistence of naturally occurring campylobacteria in aerobic compost constructed of manure from beef cattle that were administered chlortetracycline and sulfamethazine (as700) or from cattle not administered antibiotics (control) was examined. although there were no differences in population sizes of heterotrophic bacteria, the temperature of as700 compost was more variable and did not become as high as that of control compost. there were significant differences in water content, total carb ...201020023098
comparison of pcr binary typing (p-bit), a new approach to epidemiological subtyping of campylobacter jejuni, with serotyping, pulsed-field gel electrophoresis, and multilocus sequence typing methods.to overcome some of the deficiencies with current molecular typing schema for campylobacter spp., we developed a prototype pcr binary typing (p-bit) approach. we investigated the distribution of 68 gene targets in 58 campylobacter jejuni strains, one campylobacter lari strain, and two campylobacter coli strains for this purpose. gene targets were selected on the basis of distribution in multiple genomes or plasmids, and known or putative status as an epidemicity factor. strains were examined wit ...201020023103
activation of human and chicken toll-like receptors by campylobacter spp.campylobacter infection in humans is accompanied by severe inflammation of the intestinal mucosa, in contrast to colonization of chicken. the basis for the differential host response is unknown. toll-like receptors (tlrs) sense and respond to microbes in the body and participate in the induction of an inflammatory response. thus far, the interaction of campylobacter with chicken tlrs has not been studied. here, we investigated the potential of four campylobacter strains to activate human tlr1/2/ ...201020038539
activation of human and chicken toll-like receptors by campylobacter spp.campylobacter infection in humans is accompanied by severe inflammation of the intestinal mucosa, in contrast to colonization of chicken. the basis for the differential host response is unknown. toll-like receptors (tlrs) sense and respond to microbes in the body and participate in the induction of an inflammatory response. thus far, the interaction of campylobacter with chicken tlrs has not been studied. here, we investigated the potential of four campylobacter strains to activate human tlr1/2/ ...201020038539
antimicrobial susceptibilities of multidrug-resistant campylobacter jejuni and c. coli strains: in vitro activities of 20 antimicrobial agents.there is a paucity of information regarding antimicrobial agents that are suitable to treat severe infections caused by multidrug-resistant campylobacter spp. our aim was to identify agents that are potentially effective against multiresistant campylobacter strains. the in vitro activities of 20 antimicrobial agents against 238 campylobacter strains were analyzed by determining mics by the agar plate dilution method or the etest. these strains were selected from 1,808 campylobacter isolates coll ...201020038624
prevalence and risk factor investigation of campylobacter species in beef cattle feces from seven large commercial feedlots in alberta, canada.this fecal prevalence study targeted cattle from 7 large (10,000 to > 40,000 head) commercial feedlots in alberta as a means of establishing campylobacter levels in cattle just prior to animals entering the food chain. overall, 87% [95% confidence interval (ci) = 86-88] of 2776 fresh pen-floor fecal samples were culture positive for campylobacter species, with prevalences ranging from 76% to 95% among the 7 feedlots. campylobacter spp. prevalence was 88% (95% ci = 86-90) in the summer (n = 1376) ...200920046629
high-throughput identification of bacteria and yeast by matrix-assisted laser desorption ionization-time of flight mass spectrometry in conventional medical microbiology laboratories.matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) is suitable for high-throughput and rapid diagnostics at low costs and can be considered an alternative for conventional biochemical and molecular identification systems in a conventional microbiological laboratory. first, we evaluated maldi-tof ms using 327 clinical isolates previously cultured from patient materials and identified by conventional techniques (vitek-ii, api, and biochemical tests). discre ...201020053859
amoebae and algae can prolong the survival of campylobacter species in co-culture.several species of free-living amoebae can cause disease in humans. however, in addition to the direct pathogenicity of e.g. acanthamoebae and naegleria species, they are recognized as environmental hosts, indirectly involved in the epidemiology of many pathogenic bacteria. although several studies have demonstrated intracellular survival of many different bacteria in these species, the extent of such interactions as well as the implications for the epidemiology of the bacterial species involved ...201020056117
the era of molecular and other non-culture-based methods in diagnosis of sepsis.sepsis, a leading cause of morbidity and mortality throughout the world, is a clinical syndrome with signs and symptoms relating to an infectious event and the consequent important inflammatory response. from a clinical point of view, sepsis is a continuous process ranging from systemic inflammatory response syndrome (sirs) to multiple-organ-dysfunction syndrome (mods). blood cultures are the current "gold standard" for diagnosis, and they are based on the detection of viable microorganisms pres ...201020065332
comparison of campylobacter populations isolated from a free-range broiler flock before and after slaughter.relatively little is known about the campylobacter genotypes colonizing extensively reared broiler flocks and their survival through the slaughter process, despite the increasing demand for free-range and organic products by the consumer. campylobacter isolates from a free-range boiler flock, sampled before and after slaughter, were genotyped by mlst (multilocus sequence typing) and sequence analysis of the flaa short variable region (svr). the campylobacter genotypes isolated before and after s ...201020071049
understanding the molecular epidemiology of the footrot pathogen dichelobacter nodosus to support control and eradication programs.the gram-negative anaerobe dichelobacter nodosus is the primary etiologic agent of ovine footrot. few studies of the genetic diversity and epidemiology of d. nodosus have been done, despite the economic cost and welfare implications of the disease. this study examined a large collection of australian isolates; 735 isolates from footrot-infected sheep from 247 farms in western australia (wa) were tested by pulsed-field gel electrophoresis (pfge), and a subset of 616 isolates was tested by infrequ ...201020071558
understanding the molecular epidemiology of the footrot pathogen dichelobacter nodosus to support control and eradication programs.the gram-negative anaerobe dichelobacter nodosus is the primary etiologic agent of ovine footrot. few studies of the genetic diversity and epidemiology of d. nodosus have been done, despite the economic cost and welfare implications of the disease. this study examined a large collection of australian isolates; 735 isolates from footrot-infected sheep from 247 farms in western australia (wa) were tested by pulsed-field gel electrophoresis (pfge), and a subset of 616 isolates was tested by infrequ ...201020071558
expanded multilocus sequence typing and comparative genomic hybridization of campylobacter coli isolates from multiple hosts.the purpose of this work was to evaluate the evolutionary history of campylobacter coli isolates derived from multiple host sources and to use microarray comparative genomic hybridization to assess whether there are particular genes comprising the dispensable portion of the genome that are more commonly associated with certain host species. genotyping and clonalframe analyses of an expanded 16-gene multilocus sequence typing (mlst) data set involving 85 isolates from 4 different hosts species te ...201020097815
prevalence of intestinal parasitic and bacterial pathogens in diarrhoeal and non-diarroeal human stools from vhembe district, south africa.in the present study, a cross-sectional survey of intestinal parasitic and bacterial infections in relation to diarrhoea in vhembe district and the antimicrobial susceptibility profiles of isolated bacterial pathogens was conducted. stool samples were collected from 528 patients attending major public hospitals and 295 children attending two public primary schools and were analyzed by standard microbiological and parasitological techniques. entamoeba histolytica/e. dispar (34.2%) and cryptospori ...200920099757
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