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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
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
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
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
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
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
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
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
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
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
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
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
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
influence of tetracycline resistance on the transport of manure-derived escherichia coli in saturated porous media.in this research, tetracycline resistant (tet(r)) and tetracycline susceptible (tet(s)) escherichia coli isolates were retrieved from dairy manure and the influence of tetracycline resistance on the transport of e. coli in saturated porous media was investigated through laboratory column transport experiments. experimental results showed that tet(r)e. coli strains had higher mobility than the tet(s) strains in saturated porous media. measurements of cell surface properties suggested that tet(r)e ...201021211813
influence of tetracycline resistance on the transport of manure-derived escherichia coli in saturated porous media.in this research, tetracycline resistant (tet(r)) and tetracycline susceptible (tet(s)) escherichia coli isolates were retrieved from dairy manure and the influence of tetracycline resistance on the transport of e. coli in saturated porous media was investigated through laboratory column transport experiments. experimental results showed that tet(r)e. coli strains had higher mobility than the tet(s) strains in saturated porous media. measurements of cell surface properties suggested that tet(r)e ...201021211813
prevalence and antimicrobial resistance in campylobacter spp. isolated from retail chicken in two health units in ontario.campylobacter is an important enteric pathogen of humans and can cause diarrhea, fever, and abdominal pain. campylobacter infections have frequently been associated with the handling and consumption of raw and undercooked poultry. antimicrobial resistance among campylobacter strains is of concern in the treatment of campylobacteriosis in vulnerable populations. a 2-year multidisciplinary study was conducted in the perth and wellington-dufferin-guelph public health units in ontario, canada, to in ...201020615345
evaluation of salmonella-vectored campylobacter peptide epitopes for reduction of campylobacter jejuni in broiler chickens.campylobacter is a leading cause of bacterial gastroenteritis in humans and is often linked to contaminated poultry products. live salmonella vectors expressing three linear peptide epitopes from campylobacter proteins cj0113 (omp18/cjad), cj0982c (cjaa), and cj0420 (ace393) were administered to chicks by oral gavage on the day of hatch, and the chicks were challenged with campylobacter jejuni on day 21. all three candidate vaccines produced consistent humoral immune responses with high levels o ...201021177910
evaluation of salmonella-vectored campylobacter peptide epitopes for reduction of campylobacter jejuni in broiler chickens.campylobacter is a leading cause of bacterial gastroenteritis in humans and is often linked to contaminated poultry products. live salmonella vectors expressing three linear peptide epitopes from campylobacter proteins cj0113 (omp18/cjad), cj0982c (cjaa), and cj0420 (ace393) were administered to chicks by oral gavage on the day of hatch, and the chicks were challenged with campylobacter jejuni on day 21. all three candidate vaccines produced consistent humoral immune responses with high levels o ...201021177910
evolution of an agriculture-associated disease causing campylobacter coli clade: evidence from national surveillance data in scotland.the common zoonotic pathogen campylobacter coli is an important cause of bacterial gastroenteritis worldwide but its evolution is incompletely understood. using multilocus sequence type (mlst) data of 7 housekeeping genes from a national survey of campylobacter in scotland (2005/6), and a combined population genetic-phylogenetics approach, we investigated the evolutionary history of c. coli. genealogical reconstruction of isolates from clinical infection, farm animals and the environment, reveal ...201021179537
description and burden of travel-related cases caused by enteropathogens reported in a canadian community.risk of infections by enteropathogens among individuals traveling outside their country of residence is considered important. such travel-related cases (trc) have been poorly estimated and described in canada.201021199137
simple and rapid detection of campylobacter spp. in naturally contaminated chicken-meat samples by combination of a two-step enrichment method with an immunochromatographic assay.a simple and rapid method to detect campylobacter spp. in chicken-meat samples was established. this method consisted of a combination of a two-step enrichment method with a commercially available immunochromatographic assay, named nh immunochromato campylobacter (nh ic campy, nippon meat packers, ibaraki, japan), which is able to detect campylobacter antigen in an enrichment culture within 15 min. the enrichment method did not require much blood or a particular system of generating a microaerob ...201020621373
isolation and characterization of campylobacter spp. from antarctic fur seals (arctocephalus gazella) at deception island, antarctica.the presence of campylobacter spp. was investigated in 41 antarctic fur seals (arctocephalus gazella) and 9 weddell seals (leptonychotes weddellii) at deception island, antarctica. infections were encountered in six antarctic fur seals. the isolates, the first reported from marine mammals in the antarctic region, were identified as campylobacter insulaenigrae and campylobacter lari.201020639356
survival of campylobacter jejuni under conditions of atmospheric oxygen tension with the support of pseudomonas spp.campylobacter jejuni is a major food-borne pathogen. despite causing enteritis in humans, it is a well-adapted intestinal microorganism in animals, hardly ever generating disease symptoms. nevertheless, as a true microaerophilic microorganism it is still puzzling how campylobacter cells can survive on chicken meat, the main source of human infection. in this study, we demonstrate that c. jejuni is able to withstand conditions of atmospheric oxygen tension when cocultured with pseudomonas species ...201020639377
study of the molecular mechanisms involved in high-level macrolide resistance of spanish campylobacter jejuni and campylobacter coli strains.to investigate the molecular mechanisms involved in the high-level erythromycin resistance of clinical spanish campylobacter jejuni and campylobacter coli strains.201020647243
implications of faecal indicator bacteria for the microbiological assessment of roof-harvested rainwater quality in southeast queensland, australia.the study aimed to evaluate the suitability of escherichia coli, enterococci, and clostridium perfringens for assessing the microbiological quality of roof-harvested rainwater and assessing whether the concentrations of these faecal indicators can be used to predict the presence or absence of specific zoonotic bacterial or protozoan pathogens. from a total of 100 samples tested, 58%, 83%, and 46% of samples were found to be positive for, respectively, e. coli, enterococci, and clostridium perfri ...201020657617
accuracy of the api campy system, the vitek 2 neisseria-haemophilus (nh) card and the matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (maldi-tof ms) for the identification of campylobacter and related organisms.abstract biochemical identification of campylobacter and related organisms is not always specific and may lead to diagnostic errors. the api campy, the vitek 2 system and matrix-assisted desorption/ionisation time-of-flight mass spectrometry (maldi-tof ms) are commercially available methods that are routinely used for the identification of these microorganisms. in the present study, we used 224 clinical isolates and 10 reference strains previously identified by multiple pcr assays, whole-cell pr ...201020673261
antimicrobial resistance in campylobacter coli selected by tylosin treatment at a pig farm.limited knowledge is available regarding the dynamics of macrolide resistance under farm conditions with natural campylobacter populations. we examined the dynamics of antimicrobial resistance in campylobacter coli at a large pig farm. faeces were sampled from untreated sows and piglets (n=57), weaned pigs treated with tylosin (n=68) and pigs of the same group 3-5 weeks after withdrawal of tylosin (n=15). additionally, 48 weaned pigs were sampled after tylosin had not been administered for 7 mon ...201020684867
evolutionary dynamics of complete campylobacter pan-genomes and the bacterial species concept.defining bacterial species and understanding the relative cohesiveness of different components of their genomes remains a fundamental problem in microbiology. bacterial species tend to be comprised of both a set of core and dispensable genes, with the sum of these two components forming the species pan-genome. the role of the core and dispensable genes in defining bacterial species and the question of whether pan-genomes are finite or infinite remain unclear. here we demonstrate, through the ana ...201020688752
genotype and antibiotic resistance analyses of campylobacter isolates from ceca and carcasses of slaughtered broiler flocks.to obtain genetic information about campylobacter jejuni and campylobacter coli from broilers and carcasses at slaughterhouses, we analyzed and compared 340 isolates that were collected in 2008 from the cecum right after slaughter or from the neck skin after processing. we performed rpob sequence-based identification, multilocus sequence typing (mlst), and flab sequence-based typing; we additionally analyzed mutations within the 23s rrna and gyra genes that confer resistance to macrolide and qui ...201020709846
campylobacteriosis and other bacterial gastrointestinal diseases in sofia, bulgaria for the period 1987-2008.campylobacter is the most commonly reported enteric bacterial pathogen in humans. we still do not have any systematic data concerning campylobacteriosis in bulgaria. for that reason, we present data of the thermophilic campylobacter jejuni and campylobacter coli in the aetiology of diarrhoeal diseases in sofia, for the period from 1987 to 2008. the study included patients from 0 to over 65 years-old. a total of 51,607 faecal specimens were screened for campylobacter. c. jejuni and c. coli were d ...201020122383
spondylodiscitis and an aortic aneurysm due to campylobacter coli.campylobacter coli is a rare cause of bacteremia. we report here the first case of c.coli spondylodiscitis complicated by an aortic aneurysm. outcome was favourable with surgery and antibiotic therapy.201020132561
rapid detection and differentiation of campylobacter jejuni, campylobacter coli, and campylobacter lari in food, using multiplex real-time pcr.a multiplex real-time pcr assay based on four differently labeled taqman probes for detection and differentiation of the thermophilic campylobacter species c. jejuni, c. coli, and c. lari was established and validated in food products. this assay combines two previously published pcr assays for c. jejuni and c. coli with a newly developed detection assay for c. lari and an internal amplification control system. the selectivity of the method was determined by analyzing 70 campylobacter strains an ...201020132668
homopolymeric tracts represent a general regulatory mechanism in prokaryotes.while, traditionally, regulation of gene expression can be grouped into transcriptional, translational, and post-translational mechanisms, some mechanisms of rapid genetic variation can also contribute to regulation of gene expression, e.g., phase variation.201020144225
generation of the pathogenic r5-tropic simian/human immunodeficiency virus shivad8 by serial passaging in rhesus macaques.a new pathogenic r5-tropic simian/human immunodeficiency virus (shiv) was generated following serial passaging in rhesus macaques. all 13 animals inoculated with shiv(ad8) passaged lineages experienced marked depletions of cd4(+) t cells. ten of these infected monkeys became normal progressors (nps) and had gradual losses of both memory and naïve cd4(+) t lymphocytes, generated antiviral cd4(+) and cd8(+) t cell responses, and sustained chronic immune activation while maintaining variable levels ...201020147396
characterization of two diesel fuel degrading microbial consortia enriched from a non acclimated, complex source of microorganisms.the bioremediation of soils impacted by diesel fuels is very often limited by the lack of indigenous microflora with the required broad substrate specificity. in such cases, the soil inoculation with cultures with the desired catabolic capabilities (bioaugmentation) is an essential option. the use of consortia of microorganisms obtained from rich sources of microbes (e.g., sludges, composts, manure) via enrichment (i.e., serial growth transfers) on the polluting hydrocarbons would provide biorem ...201020158909
a pulsed-field gel electrophoresis study of the genetic diversity of campylobacter jejuni and campylobacter coli in poultry flocks in slovenia.campylobacter jejuni and c. coli have recently become the most frequent cause of bacterial foodborne enteric infection in most industrialised countries. consumption and handling of undercooked contaminated poultry meat was identified as an important risk factor for human campylobacteriosis. the aim of this study was to ascertain the genetic diversity of c. jejuni and c. coli strains isolated from poultry in slovenia. a total of 68 isolates (42 c. jejuni , 26 c. coli ) from faeces (n = 48), meat ...201020159735
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
proteomic analysis of iron acquisition, metabolic and regulatory responses of yersinia pestis to iron starvation.the gram-negative bacterium yersinia pestis is the causative agent of the bubonic plague. efficient iron acquisition systems are critical to the ability of y. pestis to infect, spread and grow in mammalian hosts, because iron is sequestered and is considered part of the innate host immune defence against invading pathogens. we used a proteomic approach to determine expression changes of iron uptake systems and intracellular consequences of iron deficiency in the y. pestis strain kim6+ at two phy ...201020113483
prevalence and antimicrobial resistance of campylobacter isolates in broilers from china.the prevalence and antimicrobial resistance of campylobacter spp. in broiler chickens were determined in shandong province, china. in total, 275 campylobacter isolates were obtained from 767 broiler cecal samples, including 208 campylobacter jejuni, 53 campylobacter coli, and 14 unidentified campylobacter isolates. minimal inhibitory concentrations of 11 antimicrobial agents were determined using the agar dilution method recommended by clsi. more than 98% of the tested campylobacter isolates wer ...201020116182
evaluation of diffusion and dilution methods to determine the antibacterial activity of plant extracts.the aim of this study was to evaluate diffusion and dilution methods for determining the antibacterial activity of plant extracts and their mixtures. several methods for measurement of the minimal inhibitory concentration (mic) of a plant extract are available, but there is no standard procedure as there is for antibiotics. we tested different plant extracts, their mixtures and phenolic acids on selected gram-positive (staphylococcus aureus, bacillus cereus, and listeria monocytogenes) and gram- ...201020171250
effects of polyphosphate additives on campylobacter survival in processed chicken exudates.campylobacter spp. are responsible for a large number of the bacterial food poisoning cases worldwide. despite being sensitive to oxygen and nutritionally fastidious, campylobacter spp. are able to survive in food processing environments and reach consumers in sufficient numbers to cause disease. to investigate campylobacter persistence on processed chicken, exudates from chickens produced for consumer sale were collected and sterilized. two types of exudates from chicken products were collected ...201020173061
phylogenomics reveals a diverse rickettsiales type iv secretion system.with an obligate intracellular lifestyle, alphaproteobacteria of the order rickettsiales have inextricably coevolved with their various eukaryotic hosts, resulting in small, reductive genomes and strict dependency on host resources. unsurprisingly, large portions of rickettsiales genomes encode proteins involved in transport and secretion. one particular transporter that has garnered recent attention from researchers is the type iv secretion system (t4ss). homologous to the well-studied archetyp ...201020176788
abc transporters involved in export of cell surface glycoconjugates.complex glycoconjugates play critical roles in the biology of microorganisms. despite the remarkable diversity in glycan structures and the bacteria that produce them, conserved themes are evident in the biosynthesis-export pathways. one of the primary pathways involves representatives of the atp-binding cassette (abc) transporter superfamily. these proteins are responsible for the export of a wide variety of cell surface oligo- and polysaccharides in both gram-positive and gram-negative bacteri ...201020805402
diversity and impact of prokaryotic toxins on aquatic environments: a review.microorganisms are ubiquitous in all habitats and are recognized by their metabolic versatility and ability to produce many bioactive compounds, including toxins. some of the most common toxins present in water are produced by several cyanobacterial species. as a result, their blooms create major threats to animal and human health, tourism, recreation and aquaculture. quite a few cyanobacterial toxins have been described, including hepatotoxins, neurotoxins, cytotoxins and dermatotoxins. these t ...201022069558
pulsed field gel electrophoresis typing of human and retail foodstuff campylobacters: an irish perspective.campylobacter enteritis is a zoonosis, an infectious disease transmissible under normal conditions from vertebrate animals to man, presenting a major global public health burden. in this study, pulsed field gel electrophoresis (pfge) was employed to identify common genotypes in a collection of 600 campylobacter isolates in order to investigate if profiles obtained from retail samples of foodstuffs matched genotypes causing illness in the community in ireland. the campylobacters were isolated fro ...201021356447
adherence, invasion, toxigenic, and chemotactic properties of mexican campylobacter strains.to determine the virulence factors of mexican wild-type strains of campylobacter jejuni and campylobacter coli, 31 wild-type strains were isolated from food and from humans. the production of cytolethal distending toxin and the adherence and invasion capabilities of these strains were assayed in vero cells. hard agar plugs with repellents and attractants were used to examine chemotaxis. mueller-hinton agar with supplements was used for motility analysis and to measure hemolytic activity. nine st ...201021219724
role of the pjm1 plasmid-encoded transport proteins fatb, c and d in ferric anguibactin uptake in the fish pathogen vibrio anguillarum.vibrio anguillarum serotype o1 is part of the natural flora in the aquatic habitat, but under certain circumstances it can cause terminal haemorrhagic septicemia in marine and fresh water fish due to the action of the anguibactin iron uptake system encoded by the virulence plasmid pjm1. this plasmid harbours the genes for the biosynthesis of the siderophore anguibactin and the ferric anguibactin transport proteins fatd, c, b and a encoded in the iron transport operon. the fata protein is the out ...201021304833
characterization of campylobacter jejuni and campylobacter coli strains isolated in the region of nis, serbia.campylobacter jejuni and campylobacter coli represent one of the main causes of bacterial diarrhoea in humans. although the disease is usually mild and self-limiting, severe chronic sequelae may occur, such as reactive arthritis, guillain-barré and miller fisher syndromes. serotyping is used as an epidemiological marker, while post-infective polyneuropathies are associated with several o serotypes.201021361150
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
prevalence of virulence-associated genes and cytolethal distending toxin production in campylobacter spp. isolated in italy.the prevalence of virulence and cytolethal distending toxin (cdt) genes and the cytotoxic activity in vero and hep-2 cells was estimated in 29 campylobacter jejuni and 36 campylobacter coli from foods, animals and humans isolates. all c. jejuni showed flaa, cadf, cdta, cdtb, cdtc and cdt cluster genes fragments, except for ceue (86.2%) and cdt genes (93.1%). amongst c. coli strains, a lower prevalence of ceue gene (83.3%) was detected than that for cdta, cdtb, cdtc genes (97.2%), cdt gene cluste ...201019195703
erythromycin resistance by l4/l22 mutations and resistance masking by drug efflux pump deficiency.we characterized the effects of classical erythromycin resistance mutations in ribosomal proteins l4 and l22 of the large ribosomal subunit on the kinetics of erythromycin binding. our data are consistent with a mechanism in which the macrolide erythromycin enters and exits the ribosome through the nascent peptide exit tunnel, and suggest that these mutations both impair passive transport through the tunnel and distort the erythromycin-binding site. the growth-inhibitory action of erythromycin w ...200919197244
inter- and intra-genomic heterogeneity of the intervening sequence in the 23s ribosomal rna gene of campylobacter jejuni and campylobacter coli.an intervening sequence (ivs) can be present or absent in the 23s rrna of campylobacter jejuni and campylobacter coli. as part of a survey, we used a polymerase chain reaction (pcr) assay to detect the presence of the ivs in 43 isolates of c. coli and 82 isolates of c. jejuni. an ivs was present in 40 (93.0%) of the c. coli and only 34 (41.5%) of the c. jejuni isolates. twelve (27.9%) of the c. coli isolates and seven (8.5%) of the c. jejuni isolates resulted in two polymerase chain reaction pro ...200919201124
prevalence of campylobacter jejuni and campylobacter coli in market-weight turkeys on-farm and at slaughter.to monitor the effects of feed withdrawal on the prevalence of campylobacter, market-weight turkeys from six farms were examined before and after perimarketing events (feed withdrawal, transport, and holding at the slaughterhouse). prior to transport, birds (n = 30 per farm) were slaughtered on-farm, and viscera (crops, duodenum, jejunum, ileum, colon, ceca, gallbladder, and spleen) were removed on the premises. within ca. 48 h, cohorts (n = 30 per farm) from the same flock were transported to a ...200919205462
genetic diversity of campylobacter on broiler carcasses collected preevisceration and postchill in 17 u.s. poultry processing plants.campylobacter jejuni and campylobacter coli are the most important human enteropathogens among the campylobacters. the objective of this study was to determine how diversity in campylobacter populations found on chicken carcasses collected from 17 broiler processing plants in the united states is impacted by processing. genetic diversity was determined for up to four isolates per carcass by sequencing the short variable region (svr) of the flaa locus. on 70% of campylobacter-positive carcasses, ...200919205463
genotyping of campylobacter coli isolated from humans and retail meats using multilocus sequence typing and pulsed-field gel electrophoresis.to determine the antimicrobial resistant profiles and clonality of campylobacter coli isolated from clinically ill humans and retail meats.200919226383
a pan-european survey of antimicrobial susceptibility towards human-use antimicrobial drugs among zoonotic and commensal enteric bacteria isolated from healthy food-producing animals.the aim of the study was to study antimicrobial susceptibility in escherichia coli, salmonella, campylobacter and enterococcus recovered from chickens, pigs and cattle using uniform methodology.200919233897
antiganglioside antibodies and their pathophysiological effects on guillain-barré syndrome and related disorders--a review.guillain-barré syndrome (gbs) is an acute immune-mediated polyradiculoneuropathy which can cause acute quadriplegia. infection with micro-organisms, including campylobacter jejuni (c. jejuni), haemophilus influenzae, and cytomegalovirus (cmv), is recognized as a main triggering event for the disease. lipooligosaccharide (los) genes are responsible for the formation of human ganglioside-like los structures in infectious micro-organisms that can induce gbs. molecular mimicry of loss on the surface ...200919240270
evaluation of procedures for outer membrane isolation from campylobacter jejuni.although infection with campylobacter jejuni is one of the leading causes of gastroenteritis worldwide, relatively little is known about the factors that are required to elicit a protective immune response. the need for a vaccine against this pathogen is well recognized and a number of vaccine candidates have been tested with varying degrees of success; however, there is still a lack of a suitable vaccine. to gain a better understanding of the outer-membrane protein components of this organism, ...200919246768
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
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
dynamics of campylobacter colonization of a natural host, sturnus vulgaris (european starling).wild european starlings (sturnus vulgaris) shed campylobacter at high rates, suggesting that they may be a source of human and farm animal infection. a survey of campylobacter shedding of 957 wild starlings was undertaken by culture of faecal specimens and genetic analysis of the campylobacters isolated: shedding rates were 30.6% for campylobacter jejuni, 0.6% for c. coli and 6.3% for c. lari. genotyping by multilocus sequence typing (mlst) and antigen sequence typing established that these bact ...200918826435
detection of escherichia coli, salmonella spp., shigella spp., yersinia enterocolitica, vibrio cholerae, and campylobacter spp. enteropathogens by 3-reaction multiplex polymerase chain reaction.the magnitude of bacterial diarrhea in developing countries is largely unknown because affordable detection methods are not available. we have developed a polymerase chain reaction (pcr)-based assay for use in areas with limited resources to screen for diarrheogenic strains from clinical isolates. to simplify the assay and minimize reagents, our method implemented the use of plasmids rather than bacteria as template controls and the use of bacterial suspensions or crude dna preparations rather t ...200918990527
detection of escherichia coli, salmonella spp., shigella spp., yersinia enterocolitica, vibrio cholerae, and campylobacter spp. enteropathogens by 3-reaction multiplex polymerase chain reaction.the magnitude of bacterial diarrhea in developing countries is largely unknown because affordable detection methods are not available. we have developed a polymerase chain reaction (pcr)-based assay for use in areas with limited resources to screen for diarrheogenic strains from clinical isolates. to simplify the assay and minimize reagents, our method implemented the use of plasmids rather than bacteria as template controls and the use of bacterial suspensions or crude dna preparations rather t ...200918990527
campylobacter and arcobacter species sensitivity to commercial orange oil fractions.seven orange oil fractions were screened for their ability to inhibit the growth of selected campylobacter and arcobacter spp. using the standard agar-disk diffusion assay. cold pressed (cp) terpeneless valencia orange oil was found to be the most inhibitory to both campylobacter jejuni and campylobacter coli, exhibiting maximum zones of inhibition up to 80+/-0.0 mm. five-fold concentrated valencia oil and distilled d-limonene resulted in campylobacter inhibition zones ranging from 11.0+/-1.4 to ...200919070381
diversity and habitat specificity of free-living protozoa in commercial poultry houses.despite stringent biosecurity measures, infections by bacterial food pathogens such as campylobacter are a recurrent problem in industrial poultry houses. as the main transmission route remains unclear, persistence of these infections has been linked to bacterial survival and possibly multiplication within protozoan vectors. to date, however, virtually no information is available on the diversity and occurrence of free-living protozoa in these environments. using a combination of microscopic ana ...200919124593
structures of acrr and cmer: insight into the mechanisms of transcriptional repression and multi-drug recognition in the tetr family of regulators.the transcriptional regulators of the tetr family act as chemical sensors to monitor the cellular environment in many bacterial species. to perform this function, members of the tetr family harbor a diverse ligand-binding domain capable of recognizing the same series of compounds as the transporters they regulate. many of the regulators can be induced by a wide array of structurally unrelated compounds. binding of these structurally unrelated ligands to the regulator results in a conformational ...200919130905
structures of acrr and cmer: insight into the mechanisms of transcriptional repression and multi-drug recognition in the tetr family of regulators.the transcriptional regulators of the tetr family act as chemical sensors to monitor the cellular environment in many bacterial species. to perform this function, members of the tetr family harbor a diverse ligand-binding domain capable of recognizing the same series of compounds as the transporters they regulate. many of the regulators can be induced by a wide array of structurally unrelated compounds. binding of these structurally unrelated ligands to the regulator results in a conformational ...200919130905
comparison of loop-mediated isothermal amplification assay and conventional culture methods for detection of campylobacter jejuni and campylobacter coli in naturally contaminated chicken meat samples.we investigated the efficacy of a loop-mediated isothermal amplification (lamp) assay for detection of chicken meat samples naturally contaminated with campylobacter jejuni and campylobacter coli. a total of 144 preston enrichment broth cultures from chicken meat samples were assessed by using the lamp assay and conventional culture methods, which consist of a combination of preston enrichment culturing and plating onto butzler and modified charcoal cefoperazone deoxycholate agars. compared with ...200919139242
oxidative stress-induced peptidoglycan deacetylase in helicobacter pylori.structural modification of peptidoglycan (pg) is one of the mechanisms that pathogenic bacteria use to evade the host innate immune system. for the noninvasive human gastric pathogen helicobacter pylori, pg delivery to the host cells is one trigger of the immune response. h. pylori hp310 was markedly up-expressed upon cell exposure to oxidative stress. however, disruption of hp310 did not produce a phenotype distinguishable from the parent, including oxidative stress resistance characteristics. ...200919147492
roles of lipooligosaccharide and capsular polysaccharide in antimicrobial resistance and natural transformation of campylobacter jejuni.this study is aimed to determine the role of capsular polysaccharide (cps) and lipooligosaccharide (los) in modulating antimicrobial resistance and natural transformation of campylobacter jejuni, an important food-borne human pathogen.200919147521
recombineering reveals a diverse collection of ribosomal proteins l4 and l22 that confer resistance to macrolide antibiotics.mutations in ribosomal proteins l4 and l22 confer resistance to erythromycin and other macrolide antibiotics in a variety of bacteria. l4 and l22 have elongated loops whose tips converge in the peptide exit tunnel near the macrolide-binding site, and resistance mutations typically affect residues within these loops. here, we used bacteriophage lambda red-mediated recombination, or "recombineering," to uncover new l4 and l22 alleles that confer macrolide resistance in escherichia coli. we randomi ...200919150357
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