PMID(sorted ascending)
helicobacter pylori induces apoptosis of human monocytes but not monocyte-derived dendritic cells: role of the cag pathogenicity island.monocytes are circulating precursors of the dendritic cell subset, professional antigen-presenting cells with a unique ability to initiate the innate and adaptive immune response. in this study, we have investigated the effects of wild-type helicobacter pylori strains and their isogenic mutants with mutations in known bacterial virulence factors on monocytes and monocyte-derived dendritic cells. we show that h. pylori strains induce apoptosis of human monocytes by a mechanism that is dependent o ...200415271906
occurrence of campylobacter in retail foods in ireland.a surveillance study was carried out to determine the prevalence of campylobacter in a range of retail foods purchased in three irish cities over a 20-month period between march 2001 and october 2002. in total 2391 food samples were analysed during this period. campylobacter was isolated from 444 raw chicken (49.9%), 33 turkey (37.5%) and 11 duck samples (45.8%). lower isolation rates of 7/221 (3.2%), 10/197 (5.1%) and 31/262 (11.8%) were observed for raw beef, pork and lamb, respectively. one s ...200415282123
the pattern and kinetics of substrate metabolism of campylobacter jejuni and campylobacter coli.the main aim was to investigate the patterns and kinetics of substrate oxidation by campylobacter jejuni and c. coli.200415287872
role of an inducible single-domain hemoglobin in mediating resistance to nitric oxide and nitrosative stress in campylobacter jejuni and campylobacter coli.campylobacter jejuni expresses two hemoglobins, each of which exhibits a heme pocket and structural signatures in common with vertebrate and plant globins. one of these, designated cgb, is homologous to vgb from vitreoscilla stercoraria and does not possess the reductase domain seen in the flavohemoglobins. a cgb-deficient mutant of c. jejuni was hypersensitive to nitrosating agents (s-nitrosoglutathione [gsno] or sodium nitroprusside) and a nitric oxide-releasing compound (spermine nonoate). th ...200415292134
antimicrobial susceptibilities of campylobacter isolated from food-producing animals on farms (1999-2001): results from the japanese veterinary antimicrobial resistance monitoring monitoring of antimicrobial resistance in campylobacter isolated from food-producing animals on farms was performed in japan. a total of 468 campylobacter isolates were obtained during the period from june 1999 to march 2001. campylobacter species showed high frequencies of resistance to oxytetracycline and dihydrostreptomycin. the frequencies of resistance in campylobacter coli to aminoglycosides, macrolides, tetracycline and quinolones were higher than those in campylobacter jejuni ...200415325430
antigenicity of the campylobacter coli cjaa protein produced by escherichia coli.immunogenic c. coli cjaa protein is a candidate for a chicken anti-campylobacter subunit vaccine. in order to enhance its immunogenicity an antigenic determinant of the cjaa protein was identified. thereafter, two copies of the antigenic epitope were cloned in tandem directly or with a flexible hinge between them. all experiments documented that the cjaa protein contained not only linear antigenic epitope/s but also conformational ones.200415330269
use of midi-fatty acid methyl ester analysis to monitor the transmission of campylobacter during commercial poultry processing.the presence of campylobacter spp. on broiler carcasses and in scald water taken from a commercial poultry processing facility was monitored on a monthly basis from january through june. campylobacter agar, blaser, was used to enumerate campylobacter in water samples from a multiple-tank scalder; on prescalded, picked, eviscerated, and chilled carcasses; and on processed carcasses stored at 4 degrees c for 7 or 14 days. the midi sherlock microbial identification system was used to identify campy ...200415330523
species identification by genotyping and determination of antibiotic resistance in campylobacter jejuni and campylobacter coli from humans and chickens in sweden.campylobacter is today the most common cause of human bacterial enteritis in sweden, as well as in most other industrialized countries. common sources of infection are undercooked chicken meat, unpasteurized milk and contaminated drinking water. one aim with our present study was to identify the species campylobacter jejuni and campylobacter coli strains from humans and chickens using a polymerase chain reaction/restriction enzyme analysis (pcr/rea) method, as well as traditional hippurate hydro ...200415364471
use of culture, pcr analysis, and dna microarrays for detection of campylobacter jejuni and campylobacter coli from chicken feces.a dna microarray for detection of campylobacter spp. was recently developed and applied to detect campylobacter spp. directly from chicken feces. sixty-five pooled chicken cloacal swab samples from 650 individual broiler chickens were included in the study. the results of campylobacter sp. detection obtained with dna microarrays were compared to those obtained by conventional culture and gel electrophoresis. by conventional culture, 60% of the samples were positive for either campylobacter jejun ...200415364980
campylobacter, from obscurity to celebrity.after its successful isolation from stools in the 1970s, campylobacter jejuni has rapidly become the most commonly recognised cause of bacterial gastroenteritis in man. reported cases of human campylobacteriosis represent only a small fraction of the actual number. in industrialised countries, the incidence of c. jejuni/campylobacter coli infections peaks during infancy, and again in young adults aged 15-44 years. acute self-limited gastrointestinal illness, characterised by diarrhoea, fever and ...200415373879
a european survey of antimicrobial susceptibility among zoonotic and commensal bacteria isolated from food-producing study antimicrobial resistance in zoonotic bacteria isolated from food animals in different countries using uniform methodology.200415375107
nucleotide sequences and comparison of two large conjugative plasmids from different campylobacter species.two large tetracycline resistance (tcr) plasmids have been completely sequenced, the ptet plasmid (45.2 kb) from campylobacter jejuni strain 81-176 and a plasmid pcc31 (44.7 kb) from campylobacter coli strain cc31 that was isolated from a human case of severe gastroenteritis in the uk. both plasmids are mosaic in structure, having homologues of genes found in a variety of different commensal and pathogenic bacteria, but nevertheless, showed striking similarities in dna sequence and overall gene ...200415470128
swimming and campylobacter infections.a matched case-control study was conducted to study risk factors for domestically acquired sporadic campylobacter infections in finland. swimming in natural sources of water was a novel risk factor. eating undercooked meat and drinking dug-well water were also independent risk factors for campylobacter infection.200415496253
antimicrobial resistance of campylobacter jejuni and campylobacter coli isolates in japan. 200415499812
frequency and spatial distribution of environmental campylobacter spp.humans are exposed to campylobacter spp. in a range of sources via both food and environmental pathways. for this study, we explored the frequency and distribution of thermophilic campylobacter spp. in a 10- by 10-km square rural area of cheshire, united kingdom. the area contains approximately 70, mainly dairy, farms and is used extensively for outdoor recreational activities. campylobacter spp. were isolated from a range of environmental samples by use of a systematic sampling grid. livestock ...200415528512
detection of campylobacter spp. in chicken fecal samples by real-time pcr.a real-time pcr assay for detecting thermophilic campylobacter spp. directly in chicken feces has been developed. dna was isolated from fecal material by using magnetic beads followed by pcr with a prealiquoted pcr mixture, which had been stored at -18 degrees c. campylobacter could be detected in less than 4 h, with a detection limit of 100 to 150 cfu/ml, in a fecal suspension. a bacterial internal control was added before dna extraction to control both dna isolation and the presence of pcr inh ...200415528705
sensitive and specific detection of yersinia pseudotuberculosis by loop-mediated isothermal amplification.we developed a loop-mediated isothermal amplification method able to detect yersinia pseudotuberculosis strains in 30 min by using six primers designed by targeting the inv gene. this method is more sensitive than pcr and might be a useful tool for detecting and identifying y. pseudotuberculosis.200415528740
antimicrobial resistance in campylobacter strains isolated from french broilers before and after antimicrobial growth promoter bans.the antimicrobial susceptibility of campylobacter strains isolated from standard and free-range broilers in 1992-1996 and 2001-2002 was studied.200415537699
insufficient production and tissue delivery of cd4+ memory t cells in rapidly progressive simian immunodeficiency virus infection.the mechanisms linking human immunodeficiency virus replication to the progressive immunodeficiency of acquired immune deficiency syndrome are controversial, particularly the relative contribution of cd4+ t cell destruction. here, we used the simian immunodeficiency virus (siv) model to investigate the relationship between systemic cd4+ t cell dynamics and rapid disease progression. of 18 rhesus macaques (rms) infected with ccr5-tropic sivmac239 (n=14) or cxcr4-tropic sivmac155t3 (n=4), 4 of the ...200415545355
campylobacter insulaenigrae sp. nov., isolated from marine mammals.phenotypic and phylogenetic studies were performed on four campylobacter-like organisms recovered from three seals and a porpoise. comparative 16s rrna gene sequencing studies demonstrated that the organisms represent a hitherto unknown subline within the genus campylobacter, associated with a subcluster containing campylobacter jejuni, campylobacter coli and campylobacter lari. dna-dna hybridization studies confirmed that the bacteria belonged to a single species, for which the name campylobact ...200415545485
global transposon mutagenesis and essential gene analysis of helicobacter pylori.we have constructed a genome-saturating mutant library of the human gastric pathogen helicobacter pylori. microarray tracking of transposon mutants (matt) allowed us to map the position of 5,363 transposon mutants in our library. while we generally found insertions well distributed throughout the genome, 344 genes had no detectable transposon insertions, and this list is predicted to be highly enriched for essential genes. comparison to the essential gene set of other bacteria revealed a surpris ...200415547264
pcr-restriction fragment length polymorphism assay for detection of gyra mutations associated with fluoroquinolone resistance in campylobacter coli.a fragment of the gyra gene was sequenced from 34 isolates of campylobacter coli, including 23 isolates resistant to ciprofloxacin. all ciprofloxacin-resistant isolates examined by dna sequencing carried a point mutation at position thr-86 on the gyra gene product, involving the replacement of thr-86 by ile. a combined pcr-restriction fragment length polymorphism technique using rsai was developed to detect this mutation.200415561873
regional risks and seasonality in travel-associated campylobacteriosis.the epidemiology of travel-associated campylobacteriosis is still largely unclear, and various known risk factors could only explain limited proportions of the recorded cases.200415569393
diagnostic real-time pcr for detection of salmonella in food.a robust 5' nuclease (taqman) real-time pcr was developed and validated in-house for the specific detection of salmonella in food. the assay used specifically designed primers and a probe target within the ttrrsbca locus, which is located near the salmonella pathogenicity island 2 at centisome 30.5. it is required for tetrathionate respiration in salmonella. the assay correctly identified all 110 salmonella strains and 87 non-salmonella strains tested. an internal amplification control, which is ...200415574899
characterization of lactobacillus coryniformis dsm 20001t surface protein cpf mediating coaggregation with and aggregation among pathogens.phenotypic characterization of aggregation phenotypes of lactobacillus coryniformis revealed that strain dsm 20001t coaggregated with escherichia coli k88, campylobacter coli, and campylobacter jejuni but not with other human pathogens. in addition, cells of these pathogens aggregated in the presence of the spent culture supernatant (scs) of strain dsm 20001t. cells of e. coli k88 remained viable in the coaggregates and aggregates for up to 24 h. both coaggregation and aggregation (co/aggregatio ...200415574903
survival of cold-stressed campylobacter jejuni on ground chicken and chicken skin during frozen storage.campylobacter jejuni is prevalent in poultry, but the effect of combined refrigerated and frozen storage on its survival, conditions relevant to poultry processing and storage, has not been evaluated. therefore, the effects of refrigeration at 4 degrees c, freezing at -20 degrees c, and a combination of refrigeration and freezing on the survival of c. jejuni in ground chicken and on chicken skin were examined. samples were enumerated using tryptic soy agar containing sheep's blood and modified c ...200415574906
differentiation of campylobacter coli, campylobacter jejuni, campylobacter lari, and campylobacter upsaliensis by a multiplex pcr developed from the nucleotide sequence of the lipid a gene lpxa.we describe a multiplex pcr assay to identify and discriminate between isolates of campylobacter coli, campylobacter jejuni, campylobacter lari, and campylobacter upsaliensis. the c. jejuni isolate f38011 lpxa gene, encoding a udp-n-acetylglucosamine acyltransferase, was identified by sequence analysis of an expression plasmid that restored wild-type lipopolysaccharide levels in escherichia coli strain sm105 [lpxa(ts)]. with oligonucleotide primers developed to the c. jejuni lpxa gene, nearly fu ...200415583280
sequence typing and comparison of population biology of campylobacter coli and campylobacter jejuni.a multilocus sequence typing (mlst) scheme that uses the same loci as a previously described system for campylobacter jejuni was developed for campylobacter coli. the c. coli-specific primers were validated with 53 isolates from humans, chickens, and pigs, together with 15 penner serotype reference isolates. the nucleotide sequence of the flaa short variable region (svr) was determined for each isolate. these sequence data were compared to equivalent information for 17 c. jejuni isolates represe ...200515634992
rapid detection and differentiation of pathogenic campylobacter jejuni and campylobacter coli by real-time pcr.a two-tube real-time assay, developed in a lightcycler, was used to detect, identify and differentiate campylobacter jejuni and campylobacter coli from all other pathogenic members of the family campylobacteriaceae. in the first assay, continuous monitoring of the fluorescence resonance energy transfer (fret) signal acquired from the hybridisation of two adjacent fluoroprobes, a specific fitc probe 5'-gtgctagcttgctagaacttagaga-fitc-3') and a universal downstream probe cy5 (5'-cy5-aggtgitgcatggit ...200515636755
temperature-driven campylobacter seasonality in england and wales.campylobacter incidence in england and wales between 1990 and 1999 was examined in conjunction with weather conditions. over the 10-year interval, the average annual rate was determined to be 78.4 +/- 15.0 cases per 100,000, with an upward trend. rates were higher in males than in females, regardless of age, and highest in children less than 5 years old. major regional differences were detected, with the highest rates in wales and the southwest and the lowest in the southeast. the disease displa ...200515640174
prevalence and antimicrobial resistance of thermophilic campylobacter spp. from cattle farms in washington state.the prevalence of thermophilic campylobacter spp. was investigated in cattle on washington state farms. a total of 350 thermophilic campylobacter isolates were isolated from 686 cattle sampled on 15 farms (eight dairies, two calf rearer farms, two feedlots, and three beef cow-calf ranches). isolate species were identified with a combination of phenotypic tests, hipo colony blot hybridization, and multiplex lpxa pcr. breakpoint resistance to four antimicrobials (ciprofloxacin, nalidixic acid, ery ...200515640184
chemotaxis plays multiple roles during helicobacter pylori animal infection.helicobacter pylori is a human gastric pathogen associated with gastric and duodenal ulcers as well as specific gastric cancers. h. pylori infects approximately 50% of the world's population, and infections can persist throughout the lifetime of the host. motility and chemotaxis have been shown to be important in the infection process of h. pylori. we sought to address the specific roles of chemotaxis in infection of a mouse model system. we found that mutants lacking chew, chea, or chey are all ...200515664919
characterization of cytolethal distending toxin of campylobacter species isolated from captive macaque association between certain campylobacter species and enterocolitis in humans and nonhuman primates is well established, but the association between cytolethal distending toxin and disease is incompletely understood. the purpose of the present study was to examine campylobacter species isolated from captive conventionally raised macaque monkeys for the presence of the cdtb gene and for cytolethal distending toxin activity. the identity of each isolate was confirmed on the basis of phenotypic ...200515695658
epidemiologic features of campylobacter infection among cats in the upper midwestern united describe the epidemiologic features of campylobacter infection among cats in the minneapolis-saint paul metropolitan area.200515742694
tetracycline resistance of australian campylobacter jejuni and campylobacter coli isolates.tetracycline resistance in campylobacter is encoded by the tet(o) gene and is usually associated with conjugative plasmids. little was known about tetracycline resistance in australian campylobacter species, therefore we investigated this resistance in 41 campylobacter jejuni and five campylobacter coli strains from humans and healthy chickens.200515743900
enumeration and diversity of campylobacters and bacteriophages isolated during the rearing cycles of free-range and organic chickens.campylobacters and campylobacter-specific bacteriophages were isolated and enumerated during the rearing cycle of free-range (56 days) and organic chickens (73 days) at 3-day intervals from hatching until slaughter. in both flocks campylobacter jejuni was the initial colonizer but campylobacter coli was detected more frequently from 5 weeks of age. the diversity of the campylobacter isolates was examined by pulsed-field gel electrophoresis of smai-digested genomic dna and antimicrobial resistanc ...200515746327
establishment of a universal size standard strain for use with the pulsenet standardized pulsed-field gel electrophoresis protocols: converting the national databases to the new size standard.the pulsenet national database, established by the centers for disease control and prevention in 1996, consists of pulsed-field gel electrophoresis (pfge) patterns obtained from isolates of food-borne pathogens (currently escherichia coli o157:h7, salmonella, shigella, and listeria) and textual information about the isolates. electronic images and accompanying text are submitted from over 60 u.s. public health and food regulatory agency laboratories. the pfge patterns are generated according to ...200515750058
the occurrence of campylobacter subtypes in environmental reservoirs and potential transmission identify potential reservoirs and transmission routes of human pathogenic campylobacter spp.200515752345
could flies explain the elusive epidemiology of campylobacteriosis?unlike salmonellosis with well-known routes of transmission, the epidemiology of campylobacteriosis is still largely unclear. known risk factors such as ingestion of contaminated food and water, direct contact with infected animals and outdoor swimming could at most only explain half the recorded cases.200515752427
fly transmission of annual increase in campylobacter infection in england and wales begins in may and reaches a maximum in early june. this increase occurs in all age groups and is seen in all geographic areas. examination of risk factors that might explain this seasonal increase identifies flies as a potential source of infection. the observed pattern of infection is hypothesized to reflect an annual epidemic caused by direct or indirect contamination of people by small quantities of infected material carried b ...200515757548
development of a real-time fluorescence resonance energy transfer pcr to identify the main pathogenic campylobacter spp.a simple real-time fluorescence resonance energy transfer (fret) pcr, targeting the gyra gene outside the quinolone resistance-determining region, was developed to identify campylobacter jejuni and campylobacter coli. these species were distinguished easily, as the corresponding melting points showed a difference of 15 degrees c. a second assay using the same biprobe and pcr conditions, but different pcr primers, was also developed to identify the less frequently encountered campylobacter fetus. ...200515760424
mixed diarrhoeal infection caused by vibrio cholerae and several other enteric pathogens in a 4-year-old child returning to germany from pakistan.we report a mixed enteric infection in a 4-y-old child who returned from pakistan with fever, vomiting and profuse diarrhoea leading to severe dehydration. vibrio cholerae o1, salmonella paratyphi a and campylobacter coli were cultured from stool. furthermore, giardia lamblia antigen and hepatitis a rna were detected. this is the first paediatric cholera case seen in frankfurt/main.200515764195
detection of mutations associated with macrolide resistance in thermophilic campylobacter spp. by real-time pcr.two point mutations (a2074c and a2075g) in the 23s rrna gene of campylobacter coli and c. jejuni are associated with erythromycin resistance. a real-time fluorescence resonance energy transfer pcr assay using a melting curve analysis was developed to identify these two point mutations and the wild-type genotype in thermophilic campylobacter species such as c. coli, c. jejuni, and c. lari. concerning these species, 141 strains were tested and a result obtained in 140 (99.3%). a single genotype wa ...200515770093
one-year (2003) nationwide pork carcass microbiological baseline data survey in taiwan.from january through december 2003, swab samples from 1,650 pork carcasses were collected from 39 slaughter plants in taiwan. these samples were analyzed for the prevalence of indicator microorganisms and specific pathogens. viable aerobic bacteria, total coliforms, and escherichia coli were recovered from 100, 95.3, and 87.5% of these carcasses, respectively. of those carcasses that harbored bacteria, the mean aerobic plate, total coliform, and escherichia coli counts were 4.0, 0.6, and 0.1 log ...200515771166
prevalence of campylobacter, salmonella, and escherichia coli on the external packaging of raw meat.during september and october 2002, 3,662 prepackaged raw meat samples were collected to evaluate the extent and nature of microbiological contamination on external surfaces of the packaging, which could potentially cross-contaminate ready-to-eat foods during and after purchase. salmonella was detected on two (<1%) samples of external packaging (both from raw chicken), and campylobacter was detected on 41 (1.1%) samples of external packaging. the external packaging of game fowl exhibited the high ...200515771168
function of neisserial outer membrane phospholipase a in autolysis and assessment of its vaccine potential.outer membrane phospholipase a (ompla) is an outer membrane-localized enzyme, present in many gram-negative bacterial species. it is implicated in the virulence of several pathogens. here, we investigated the presence, function, and vaccine potential of ompla in the human pathogen neisseria meningitidis. immunoblot analysis showed the presence of ompla in 28 out of 33 meningococcal strains investigated. the ompla-negative strains all contained a plda gene, but these alleles contained premature s ...200515784566
pcr identification of campylobacter coli and campylobacter jejuni by partial sequencing of virulence genes.the objective of this study was to utilize a multiplex pcr assay for concurrent detection of campylobacter spp. and c. coli or c. jejuni, using probes derived from genes cadf and ceue and an undefined virulence gene. a total of 97 campylobacter strains, isolated from turkey litter (n=74), chicken livers (n=15) and clinical (n=8) samples, were speciated using the pcr-based assay. pcr amplification of the isolates identified a 400-bp cadf gene, conserved in campylobacter species, an 894-bp ceue ge ...200515797819
prevalence and genetic diversity of campylobacter spp. in environmental water samples from a 100-square-kilometer predominantly dairy farming area.water samples were taken systematically from a 100-km2 area of mainly dairy farmland in northwestern england and examined for campylobacter spp. pulsed-field gel electrophoresis-restriction fragment length polymorphism (pfge-rflp) and flaa strain typing of campylobacter jejuni and campylobacter coli isolates were done. data on the water source and the adjacent environment were recorded and examined as explanatory variables. campylobacter spp. were isolated from 40.5% (n = 119) of the water sampl ...200515812015
identification and molecular epidemiology of campylobacter coli isolates from human gastroenteritis, food, and animal sources by amplified fragment length polymorphism analysis and penner serotyping.campylobacter coli is an infrequently studied but important food-borne pathogen with a wide natural distribution. we investigated its molecular epidemiology by use of amplified fragment length polymorphism (aflp)-based genotyping and penner serotyping. serotype reference strains and 177 danish isolates of diverse origin identified by routine phenotyping as c. coli were examined. molecular tools identified some 12% of field isolates as campylobacter jejuni, emphasizing the need for improved ident ...200515812025
differential detection of five mouse-infecting helicobacter species by multiplex pcr.several species of helicobacter have been isolated from laboratory mice, including h. bilis, h. hepaticus, h. muridarum, h. rodentium, and h. typhlonius, which appear to be the most common. the most widely used published method for molecular detection of these agents is pcr amplification of a conserved region of 16s rrna, but differential speciation requires restriction enzyme digestion of the amplicons. this study was undertaken to determine pcr conditions that would simultaneously and specific ...200515817762
prevalence and diversity of campylobacter jejuni in pig herds on farms with and without cattle or poultry.the prevalence and diversity of campylobacter jejuni was investigated in pig herds on farms with and without cattle or poultry production. a bacteriological screening of pig cecal samples from 247 finisher herds was carried out at the slaughter-house. subsequently, a follow-up study was conducted in 24 herds (either with or without prior c. jejuni isolation from pigs) in which fecal samples were collected from pigs and, if present, cattle and poultry. samples were analyzed for presence of campyl ...200515830662
phosphorylation-independent activity of atypical response regulators of helicobacter pylori.the genome of the gastric pathogen helicobacter pylori harbors a remarkably low number of regulatory genes, including three and five open reading frames encoding two-component histidine kinases and response regulators, respectively, which are putatively involved in transcriptional regulation. two of the response regulator genes, hp1043 and hp166, proved to be essential for cell growth, and inactivation of the response regulator gene hp1021 resulted in a severe growth defect, as indicated by a sm ...200515838037
cytolethal distending toxin (cdt)-negative campylobacter jejuni strains and anti-cdt neutralizing antibodies are induced during human infection but not during colonization in chickens.the cytolethal distending toxin (cdt) of campylobacter jejuni was detectable, using an in vitro assay, in most but not all of 24 strains tested. the reason for the absence of toxin activity in these naturally occurring cdt-negative c. jejuni strains was then investigated at the genetic level. cdt is encoded by three highly conserved genes, cdta, -b, and -c. in the cdt-negative strains, two types of mutation were identified. the cdt activities of c. jejuni strains possessing both types of mutatio ...200515845513
evaluation of a pcr assay for the detection and identification of campylobacter jejuni and campylobacter coli in retail poultry products.a pcr-based method was applied to campylobacter detection in poultry samples at the retail level. in total, 73 retail poultry samples purchased from supermarkets in the basque country area in the north of spain were examined using both culture and molecular (alternative) methods. in our routine method, the worldwide iso 10272:1995 standard of preston broth incubated at 42 degrees c for conventional campylobacter detection was adopted. the molecular method was comprised of a dna extraction kit co ...200515862456
crga is an inducible lysr-type regulator of neisseria meningitidis, acting both as a repressor and as an activator of gene transcription.the crga gene of neisseria meningitidis, which codes for a lysr-type regulator, is divergently oriented with respect to the mdab gene, which codes for a hypothetical nadph-quinone oxidoreductase. transcriptional studies of the intergenic region between crga and mdab showed that two overlapping and divergent promoters, p(crga) and p(mdab), control transcription of these genes. deletion of the crga gene led to a strong increase in transcription from the p(crga) promoter and a concomitant strong de ...200515866928
extended multilocus sequence typing system for campylobacter coli, c. lari, c. upsaliensis, and c. helveticus.a multilocus sequence typing (mlst) system has been reported previously for campylobacter jejuni to both differentiate strains and identify clonal lineages. however, sequence variation at the mlst loci prevents its use for closely related campylobacter species. we describe herein an expanded mlst method to include three clinically relevant campylobacter species, c. coli, c. lari, and c. upsaliensis, and a fourth campylobacter species, c. helveticus. the c. coli and c. helveticus methods use the ...200515872261
oral campylobacter species involved in extraoral abscess: a report of three cases.oral campylobacter species are rarely reported to cause extraoral infections. here we present three cases of extraoral abscess caused by an oral campylobacter sp. and a streptococcus sp. the campylobacter species were all isolated anaerobically and identified by sequencing analysis of the 16s rrna gene. the cases included a breast abscess caused by campylobacter rectus and a non-group a beta-hemolytic streptococcus in a patient with lymphoma, a liver abscess caused by campylobacter curvus and an ...200515872299
clinical herd health, farm management and antimicrobial resistance in campylobacter coli on finishing pig farms in switzerland.the world-wide increase of antimicrobial resistance in micro-organisms complicates medical treatment of infected humans. we did a risk-factor analysis for the prevalence of antimicrobial resistant campylobacter coli on 64 swiss pig finishing farms. between may and november 2001, 20 faecal samples per farm were collected from the floor of pens holding finishing pigs shortly before slaughter. samples were pooled and cultured for campylobacter species. isolated campylobacter strains were tested for ...200515907569
analysis of the prevalence of tetracycline resistance genes in clinical isolates of enterococcus faecalis and enterococcus faecium in a japanese hospital.prevalence of seven tetracycline resistance (tc(r)) genes--tet(l), tet(m), tet(k), tet(o), tet(s), tet(t), and tet(u)--which are known to be distributed to gram-positive cocci was analyzed for 224 enterococcus faecalis and 46 enterococcus faecium clinical isolates obtained in a japanese hospital. any of the tc(r) genes was detected in 75.9% of all the enterococcal strains. the tet(m) was detected at highest rates in both e. faecalis (75.0%) and e. faecium (69.6%), followed by tet(l), which was h ...200515910229
[distribution and genetic characterization of porcine campylobacter coli isolates].the aim of this study was to evaluate the impact of the slaughter process on the campylobacter (c.) coli prevalence on pig carcasses and finally pork. to detect c. spp., faecal samples, organ samples and surfaces of slaughter pigs were sampled. additionally, various abattoir surfaces (n=208) and 227 pork and minced meat samples were included in our study. whereas a high c. spp. prevalence (64.0%) was detectable in the faeces of slaughter pigs (all isolates were identified as c. coli), low detect ...200515918485
a new approach for the analysis of bacterial microarray-based comparative genomic hybridization: insights from an empirical study.microarray-based comparative genomic hybridization (m-cgh) has been used to characterize the extensive intraspecies genetic diversity found in bacteria at the whole-genome level. although conventional microarray analytical procedures have proved adequate in handling m-cgh data, data interpretation using these methods is based on a continuous character model in which gene divergence and gene absence form a spectrum of decreasing gene conservation levels. however, whereas gene divergence may yet b ...200515918914
mama-pcr assay for the detection of point mutations associated with high-level erythromycin resistance in campylobacter jejuni and campylobacter coli strains.twenty campylobacter jejuni and 16 campylobacter coli strains isolated from humans and food/animals, including 17 isolates resistant to erythromycin, were analyzed. a combined mismatch amplification mutation assay-pcr technique was developed to detect the mutations a 2074 c and a 2075 g in the 23s rrna gene associated with erythromycin resistance. all high-level erythromycin-resistant strains examined by dna sequencing carried the transition mutation a 2075 g, whereas no isolate carried the a 20 ...200515927294
birds, migration and emerging zoonoses: west nile virus, lyme disease, influenza a and enteropathogens.wild birds are important to public health because they carry emerging zoonotic pathogens, either as a reservoir host or by dispersing infected arthropod vectors. in addition, bird migration provides a mechanism for the establishment of new endemic foci of disease at great distances from where an infection was acquired. birds are central to the epidemiology of west nile virus (wnv) because they are the main amplifying host of the virus in nature. the initial spread of wnv in the u.s. along the ea ...200315931279
effect of preslaughter events on prevalence of campylobacter jejuni and campylobacter coli in market-weight turkeys.the effects of events which occur prior to slaughter, such as loading, transport, and holding at an abattoir, on the prevalence of campylobacter species, including campylobacter jejuni and campylobacter coli, were examined. cloacal swabs from market-weight turkeys in each of five flocks were obtained on a farm prior to loading (time 1; 120 swabs per flock) and after transport and holding at the abattoir (time 2; 120 swabs per flock). a statistically significant increase in the overall prevalence ...200515932973
genetic diversity and antibiotic resistance patterns in a campylobacter population isolated from poultry farms in switzerland.the diversity and genetic interrelation of campylobacter jejuni and c. coli isolated from swiss poultry were assessed by three independent typing methods. samples were derived prior to slaughter from 100 randomly selected flocks (five birds per flock) raised on three different farm types. the observed flock prevalence was 54% in total, with 50% for conventional and 69% for free-range farms. birds held on farms with a confined roaming area had the lowest prevalence of 37%. campylobacter isolates ...200515932975
evaluation of agar plates for direct enumeration of campylobacter spp. from poultry carcass rinses.campy-cefex, a modification of campy-cefex, modified charcoal cefoperazone deoxycholate (mccda), karmali, campy, and campy-line agars were evaluated for their efficiency to isolate and enumerate campylobacter spp. from poultry carcass rinses. campy-cefex and its modification produced the best results but were statistically similar to campy, mccda, and karmali.200515933040
prevalence of potential virulence markers in polish campylobacter jejuni and campylobacter coli isolates obtained from hospitalized children and from chicken carcasses.the pathogenicity of thermotolerant campylobacter species, common food-borne pathogens, depends on certain factors unevenly distributed among strains of different origin. the prevalence of such markers has never been examined in a population of polish campylobacter strains of human and poultry origin. therefore, we analysed the presence of the cadf, cdta, cdtb and cdtc genes and the iam sequence in campylobacter jejuni (n = 115) and campylobacter coli (n = 57) isolates from children with diarrho ...200515947425
prevalence of salmonella, campylobacter and vtec on pig farms.four different pig farms were sampled for the prevalence of salmonella, campylobacter and verotoxigenic e. coli (vtec). pigs of different age groups and pigs of the same age were tested by taking rectal swabs. the farm environment was tested by examining overshoes, and the feed and drinking water in the pens. from a total of 215 rectal samples of individual pigs, 15 rectal samples taken from animals at the same farm were positive for salmonella. the salmonella status of the pigs at this farm dif ...200115954621
h-ns is a part of a thermally controlled mechanism for bacterial gene regulation.temperature is a primary environmental stress to which micro-organisms must be able to adapt and respond rapidly. whereas some bacteria are restricted to specific niches and have limited abilities to survive changes in their environment, others, such as members of the enterobacteriaceae, can withstand wide fluctuations in temperature. in addition to regulating cellular physiology, pathogenic bacteria use temperature as a cue for activating virulence gene expression. this work confirms that the n ...200515966862
stable accumulation of sigma54 in helicobacter pylori requires the novel protein hp0958.several flagellar genes in helicobacter pylori are dependent on sigma(54) (rpon) for their expression. these genes encode components of the basal body, the hook protein, and a minor flagellin, flab. a protein-protein interaction map for h. pylori constructed from a high-throughput screen of a yeast two-hybrid assay ( revealed interactions between sigma(54) and the conserved hypothetical protein hp0958. to see if hp0958 influences sigma(54) function, ...200515968056
[antimicrobial susceptibility of campylobacter jejuni and campylobacter coli isolated from human diarrheic samples].one hundred forty-seven campylobacter were isolated using 3,204 samples taken from sporadic diarrheic patients from january 2001 to december 2003. the detection rate of campylobacter in 16 to 30 year old patients (12.9%, 83/641) was significantly higher than that in patients less than 16 years of age, 5%, (29/1,155) (p < 0.001) and more than 30 years of age, 2.5% (35/1,408) (p < 0.001), respectively. the highest detection rate was obtained from the stool of males in the 16 to 30 year old range d ...200515977557
macrolide resistance in campylobacter jejuni and campylobacter coli: molecular mechanism and stability of the resistance phenotype.a collection of 23 macrolide-resistant campylobacter isolates from different geographic areas was investigated to determine the mechanism and stability of macrolide resistance. the isolates were identified as campylobacter jejuni or campylobacter coli based on the results of the hippurate biochemical test in addition to five pcr-based genotypic methods. three point mutations at two positions within the peptidyl transferase region in domain v of the 23s rrna gene were identified. about 78% of the ...200515980346
agricultural antibiotics and human health. 200515984910
strain persistence and fluctuation of multiple-antibiotic resistant campylobacter coli colonizing turkeys over successive production cycles.the dynamics of colonization of turkeys by thermophilic campylobacters that are resistant to multiple antibiotics is poorly understood. in this study, we monitored cecal colonization of turkeys by campylobacter over three successive production cycles at the same farm. campylobacter isolated from the ceca was predominantly c. coli in all three flocks. isolates with two distinct fla types that represented a single clonal group based on pulsed-field gel electrophoresis and that were resistant to mu ...200515992304
further characterization of campylobacter isolated from u.s. dairy cows.the objective of the present study was to compare polymerase chain reaction (pcr) identification with ribotype results and to use pulsed field electrophoresis (pfge) to correlate genotypic patterns with antibiotic resistance of campylobacter isolated from lactating dairy cows in the united states. thirty isolates were studied. twenty-seven of the isolates were identified by pcr as campylobacter jejuni and three were identified as campylobacter coli. genotypic patterns of 15 isolates were determi ...200515992313
effects of subtherapeutic administration of antimicrobial agents to beef cattle on the prevalence of antimicrobial resistance in campylobacter jejuni and campylobacter hyointestinalis.the influence of antimicrobial agents on the development of antimicrobial resistance (amr) in campylobacter isolates recovered from 300 beef cattle maintained in an experimental feedlot was monitored over a 315-day period (11 sample times). groups of calves were assigned to one of the following antimicrobial treatments: chlortetracycline and sulfamethazine (cs), chlortetracycline alone (ct), virginiamycin, monensin, tylosin phosphate, and no antimicrobial agent (i.e., control treatment). in tota ...200516000800
prevalence and antimicrobial resistance of campylobacter spp. and salmonella serovars in organic chickens from maryland retail stores.retail organic (n = 198) and conventional (n = 61) chickens were analyzed. most organic (76%) and conventional (74%) chickens were contaminated with campylobacters. salmonellae were recovered from 61% of organic and 44% of conventional chickens. all salmonella enterica serovar typhimurium isolates from conventional chickens were resistant to five or more antimicrobials, whereas most s. enterica serovar typhimurium isolates (79%) from organic chickens were susceptible to 17 antimicrobials tested.200516000828
advantages of peptide nucleic acid oligonucleotides for sensitive site directed 16s rrna fluorescence in situ hybridization (fish) detection of campylobacter jejuni, campylobacter coli and campylobacter lari.traditionally fluorescence in situ hybridization (fish) has been performed with labeled dna oligonucleotide probes. here we present for the first time a high affinity peptide nucleic acid (pna) oligonucleotide sequence for detecting thermotolerant campylobacter spp. using fish. thermotolerant campylobacter spp, including the species campylobacter coli, campylobacter jejuni and campylobacter lari, are important food and water borne pathogens. the designed pna probe (cje195) bound with higher affi ...200516009278
rapid decay of salmonella flagella antibodies during human gastroenteritis: a follow up indirect enzyme-linked immunosorbent assay (elisa) based on salmonella re-polymerized flagella was employed to measure levels of immunoglobulin (ig) g, igm and iga antibodies in sera from 303 danish patients diagnosed with either salmonella enteritidis or salmonella typhimurium. the antibody-levels were assessed at one, three and six months after onset of salmonellosis, and sera from a control-group of 170 healthy blood donors were additionally analysed in order to establish cut-off values fo ...200516009280
[establishment of immunomagnetic capture-fluorescent pcr detection method for campylobacter jejuni].in order to develop a rapid method which can check campylobacter jejuni in animal and poultry foods nicely, an immunomagnetic capture-fluorescent pcr (imc-fpcr) method was established in this paper. the reported method involves isolation of the target pathogen by immunocapture prior to the fluorescent pcr step, therefore the immunomagnetic-beads for campylobacter were developed, and two groups of primer/probe, which targeted for the species special sequence of flaa gene and hipo gene for campylo ...200516013502
resistance of human periodontal ligament fibroblasts to the cytolethal distending toxin of actinobacillus actinomycetemcomitans.the cytolethal distending toxin (cdt) of actinobacillus actinomycetemcomitans is a typical member of this gram-negative bacterium holotoxin family that targets a wide spectrum of eukarytotic cells, typically causing cell cycle arrest at either the g(1) or g(2)/m phase of the cell cycle. in view of the possible role of the cdt as a prominent a. actinomycetemcomitans virulence factor in periodontal diseases, we have examined the effects of the toxin on primary cultures of human periodontal ligamen ...200516018764
origin and evolution of the archaeo-eukaryotic primase superfamily and related palm-domain proteins: structural insights and new members.we report an in-depth computational study of the protein sequences and structures of the superfamily of archaeo-eukaryotic primases (aeps). this analysis greatly expands the range of diversity of the aeps and reveals the unique active site shared by all members of this superfamily. in particular, it is shown that eukaryotic nucleo-cytoplasmic large dna viruses, including poxviruses, asfarviruses, iridoviruses, phycodnaviruses and the mimivirus, encode aeps of a distinct family, which also includ ...200516027112
identification of a d-glycero-d-manno-heptosyltransferase gene from helicobacter pylori.we have identified a helicobacter pylori d-glycero-d-manno-heptosyltransferase gene, hp0479, which is involved in the biosynthesis of the outer core region of h. pylori lipopolysaccharide (lps). insertional inactivation of hp0479 resulted in formation of a truncated lps molecule lacking an alpha-1,6-glucan-, dd-heptose-containing outer core region and o-chain polysaccharide. detailed structural analysis of purified lps from hp0479 mutants of strains ss1, 26695, o:3, and pj1 by a combination of c ...200516030209
antimicrobial resistance patterns of campylobacter from feedlot cattle*.this study examined 448 campylobacter strains isolated in 1999 and 2000 from us feedlot cattle for resistance to 12 antimicrobials.200516033459
development of real-time pcr and hybridization methods for detection and identification of thermophilic campylobacter spp. in pig faecal develop a real-time (rt) pcr for species differentiation of thermophilic campylobacter and to develop a method for assessing co-colonization of pigs by campylobacter spp.200516033460
real-time pcr screening for 16s rrna mutations associated with resistance to tetracycline in helicobacter pylori.the effectiveness of recommended first-line therapies for helicobacter pylori infections is decreasing due to the occurrence of resistance to metronidazole and/or clarithromycin. quadruple therapies, which include tetracycline and a bismuth salt, are useful alternative regimens. however, resistance to tetracycline, mainly caused by mutations in the 16s rrna genes (rrna and rrnb) affecting nucleotides 926 to 928, are already emerging and can impair the efficacies of such second-line regimens. her ...200516048919
role of efflux pumps and topoisomerase mutations in fluoroquinolone resistance in campylobacter jejuni and campylobacter coli.point mutations in the topoisomerase (dna gyrase a) gene are known to be associated with fluoroquinolone resistance in campylobacter. recent studies have shown that an efflux pump encoded by cmeabc is also involved in decreased susceptibilities to fluoroquinolones, as well as other antimicrobials. genome analysis suggests that campylobacter jejuni contains at least nine other putative efflux pumps. using insertional inactivation and site-directed mutagenesis, we investigated the potential contri ...200516048946
etiology of diarrhea in young children in denmark: a case-control study.infectious gastroenteritis is one of the most common diseases in young children. to clarify the infectious etiology of diarrhea in danish children less than 5 years of age, we conducted a 2-year prospective case-control study. stools from 424 children with diarrhea and 870 asymptomatic age-matched controls were examined, and their parents were interviewed concerning symptoms. rotavirus, adenovirus, and astrovirus were detected by enzyme-linked immunosorbent assay, and norovirus and sapovirus wer ...200516081890
genetic diversity of campylobacter sp. isolates from retail chicken products and humans with gastroenteritis in central michigan.multilocus sequencing was used to compare campylobacter sp. strains isolated from retail chicken products and humans with gastroenteritis in central michigan. sequence comparisons demonstrated overlapping diversity between chicken and human isolates. campylobacter jejuni isolates from clinical sources had a greater diversity of flagellin alleles and a higher rate of quinolone resistance than isolates from retail chicken products.200516081984
inhibition of clostridium perfringens by a novel strain of bacillus subtilis isolated from the gastrointestinal tracts of healthy chickens.the objectives of this study were to isolate beneficial strains of microorganisms from the gastrointestinal tracts of healthy chickens and to screen them against clostridium perfringens, a causative agent of necrotic enteritis in poultry. one of the bacteria isolated, a strain of bacillus subtilis, was found to possess an anticlostridial factor that could inhibit the c. perfringens atcc 13124 used in this study. the anticlostridial factor produced by b. subtilis pb6 was found to be fully or part ...200516085801
discrimination of enterobacterial repetitive intergenic consensus pcr types of campylobacter coli and campylobacter jejuni by fourier transform infrared spectroscopy.fourier transform infrared spectroscopy (ft-ir) has been used together with pattern recognition methodology to study isolates belonging to the species campylobacter coli and campylobacter jejuni and to compare ft-ir typing schemes with established genomic profiles based on enterobacterial repetitive intergenic consensus pcr (eric-pcr). seventeen isolates were cultivated under standardized conditions for 2, 3, and 4 days to study variability and improve reproducibility. eric-pcr profiles and ft-i ...200516085819
news and notes: an atypical campylobacter coli exhibiting unusual morphology.campylobacter coli cells are characterized by a comma, or spiral shape, and a single polar flagellum. here we report stable spontaneous changes in morphology to an aflagellated straight rod. the ability to colonize the chick cecum was lost. the atypical cells were compared with the original c. coli 67 culture from which they were derived, with pcr, riboprinting, and pfge.200516091850
a newly constructed primer pair for the pcr amplification, cloning and sequencing of the flagellin (flaa) gene from isolatesof urease-negative campylobacter lari.a newly constructed primer pair (lari-af/lari-ar) designed to generate a product of the flagellin (flaa) gene for urease-negative campylobacter lari produced a pcr amplicon of about 1700 bp for 16 isolates from 7 seagulls, 5 humans, 3 food animals and one mussel in japan and northern ireland. nucleotide sequencing and alignments of the flaa amplicons from these isolates demonstrated that the deduced amino acid sequences of the possible open reading frame were 564-572 amino acid residues in lengt ...200516096687
campylobacter spp., salmonella spp., verocytotoxic escherichia coli, and antibiotic resistance in indicator organisms in wild cervids.faecal samples were collected, as part of the national health surveillance program for cervids (hop) in norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. samples from a total of 618 animals were examined for verocytotoxic e. coli (vtec); 611 animals for salmonella and 324 animals for campylobacter. a total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species e. coli and enterococcus fa ...200516108210
identification of a new family of enzymes with potential o-acetylpeptidoglycan esterase activity in both gram-positive and gram-negative bacteria.the metabolism of the rigid bacterial cell wall heteropolymer peptidoglycan is a dynamic process requiring continuous biosynthesis and maintenance involving the coordination of both lytic and synthetic enzymes. the o-acetylation of peptidoglycan has been proposed to provide one level of control on these activities as this modification inhibits the action of the major endogenous lytic enzymes, the lytic transglycosylases. the o-acetylation of peptidoglycan also inhibits the activity of the lysozy ...200516111493
does age acquired immunity confer selective protection to common serotypes of campylobacter jejuni?campylobacter infection is a major cause of bacterial gastrointestinal disease. exposure to campylobacter is known to produce an immune response in humans that can prevent future symptomatic infections. further, studies of the general population have shown that seroprevalence to campylobacter increases with age.200516117832
sequence analysis of two cryptic plasmids from an agricultural isolate of campylobacter part of a study identifying plasmids in campylobacter, we isolated and sequenced two novel cryptic plasmids from an agricultural isolate of campylobacter coli. the larger of the two plasmids, p3384, is 3316 bp in length and has a g+c content of 31.18%. a typical origin of replication consisting of five iterons was observed directly upstream of the first of three putative orfs. the smaller plasmid, p3386, is 2426 bp in length and has a g+c content of 26.22%. of the three putative orfs detected ...200616120460
identification and characterization of neub3 from campylobacter jejuni as a pseudaminic acid synthase.campylobacter jejuni and campylobacter coli are the main causes of bacterial diarrhea worldwide, and helicobacter pylori is known to cause duodenal ulcers. in all of these pathogenic organisms, the flagellin proteins are heavily glycosylated with a 2-keto-3-deoxy acid, pseudaminic acid (5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-l-manno-nonulosonic acid). the presence of pseudaminic acid is required for the proper development of the flagella and is thereby necessary for motility in, and invasi ...200516120604
campylobacter coli: prevalence and antimicrobial resistance in antimicrobial-free (abf) swine production determine the prevalence and antimicrobial resistance of campylobacter species in swine reared in the intensive and extensive antimicrobial-free (abf) production systems at farm and slaughter. in the abf system, antimicrobials are neither used for growth promotion nor therapeutic purposes.200516120624
involvement of the cmeabc efflux pump in the macrolide resistance of campylobacter coli.this study was conducted to examine the role of the cmeabc efflux pump in decreasing the susceptibility of campylobacter coli to macrolides and ketolides in the context of absence or presence of mutations in the 23s rrna genes.200516157618
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