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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
fly transmission of campylobacter.an 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
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
the occurrence of campylobacter subtypes in environmental reservoirs and potential transmission routes.to identify potential reservoirs and transmission routes of human pathogenic campylobacter spp.200515752345
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
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
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
epidemiologic features of campylobacter infection among cats in the upper midwestern united states.to describe the epidemiologic features of campylobacter infection among cats in the minneapolis-saint paul metropolitan area.200515742694
characterization of cytolethal distending toxin of campylobacter species isolated from captive macaque monkeys.an 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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
antimicrobial resistance of campylobacter jejuni and campylobacter coli isolates in japan. 200415499812
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
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
a european survey of antimicrobial susceptibility among zoonotic and commensal bacteria isolated from food-producing animals.to study antimicrobial resistance in zoonotic bacteria isolated from food animals in different countries using uniform methodology.200415375107
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
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
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 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
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
antimicrobial susceptibilities of campylobacter isolated from food-producing animals on farms (1999-2001): results from the japanese veterinary antimicrobial resistance monitoring program.nationwide 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
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
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
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
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
a real-time multiplexed pcr assay for rapid detection and differentiation of campylobacter jejuni and campylobacter coli.campylobacter species are the leading agents of bacterial gastroenteritis worldwide. c. jejuni and c. coli together are responsible for more than 95% of all cases of campylobacter-induced diarrheal disease in the united states. detection of campylobacteria in clinical samples by conventional culture is problematic and slow due to their complex taxonomy, fastidious growth requirements, and biochemical inertness. the current study describes a rapid, sensitive, and specific real-time polymerase cha ...200415271389
campylobacter prevalence in lactating dairy cows in the united states.the objective of the present study was to determine the prevalence of intestinal campylobacter in lactating dairy cows from various regions of the united states. participating commercial dairy farms were chosen at random and were part of a national survey to determine e. coli o157:h7 and salmonella prevalence in dairy cows. farms had no previous history of campylobacter problems. fecal samples were collected rectally from 720 cows on farms in the northeast (four farms), in the desert southwest ( ...200415270504
campylobacter colonization of sibling turkey flocks reared under different management conditions.uncertainty exists concerning the key factors contributing to campylobacter colonization of poultry, especially the possible role of vertical transmission from breeder hens to young birds. a longitudinal study of campylobacter colonization was performed in two sibling pairs of turkey flocks (four flocks total). each pair of sibling flocks shared breeder hen populations and was obtained from the same hatchery. one flock of each pair was grown on a commercial farm, and the other was grown in an in ...200415270502
phase and antigenic variation in bacteria.phase and antigenic variation result in a heterogenic phenotype of a clonal bacterial population, in which individual cells either express the phase-variable protein(s) or not, or express one of multiple antigenic forms of the protein, respectively. this form of regulation has been identified mainly, but by no means exclusively, for a wide variety of surface structures in animal pathogens and is implicated as a virulence strategy. this review provides an overview of the many bacterial proteins a ...200415258095
characterization of plasmid-mediated apha-3 kanamycin resistance in campylobacter jejuni.a total of 254 isolates of campylobacter jejuni and three isolates of campylobacter coli, isolated from sweden, canada, and egypt, were screened for kanamycin resistance. eight strains of c. jejuni contained large plasmids that carried the apha-3 kanamycin-resistance marker. in six plasmids, the apha-3 gene was located downstream of an apparent insertion sequence, designated is607*, which showed a considerable similarity to is607, characterized on the chromosome of some helicobacter pylori strai ...200415256024
multiplex pcr assay for detection of streptococcus suis species and serotypes 2 and 1/2 in tonsils of live and dead pigs.a pcr assay was developed for the detection of streptococcus suis serotypes 2 and 1/2. this multiplex pcr is based on the amplification of the gene coding for 16s rrna of s. suis and on the amplification of the cps2j gene coding for the capsule of s. suis serotypes 2 and 1/2. an internal control was constructed and added in this test to monitor the efficiency of amplification in each reaction. to evaluate the specificity of the test, 31 strains of other bacterial species related to s. suis or is ...200415243078
identification of bacterial populations in dairy wastewaters by use of 16s rrna gene sequences and other genetic markers.hydraulic flush waste removal systems coupled to solid/liquid separators and circulated treatment lagoons are commonly utilized to manage the large amounts of animal waste produced on high-intensity dairy farms. although these systems are common, little is known about the microbial populations that inhabit them or how they change as they traverse the system. using culture-based and non-culture-based methods, we characterized the microbial community structure of manure, water from the separator p ...200415240310
longitudinal study of campylobacter jejuni bacteriophages and their hosts from broiler chickens.a longitudinal study of bacteriophages and their hosts was carried out at a broiler house that had been identified as having a population of campylobacter-specific bacteriophages. cloacal and excreta samples were collected from three successive broiler flocks reared in the same barn. campylobacter jejuni was isolated from each flock, whereas bacteriophages could be isolated from flocks 1 and 2 but were not isolated from flock 3. the bacteriophages isolated from flocks 1 and 2 were closely relate ...200415240258
iron acquisition and regulation in campylobacter jejuni.iron affects the physiology of bacteria in two different ways: as a micronutrient for bacterial growth and as a catalyst for the formation of hydroxyl radicals. in this study, we used dna microarrays to identify the c. jejuni genes that have their transcript abundance affected by iron availability. the transcript levels of 647 genes were affected after the addition of iron to iron-limited c. jejuni cells. several classes of affected genes were revealed within 15 min, including immediate-early re ...200415231804
helicobacter pylori flgr is an enhancer-independent activator of sigma54-rna polymerase holoenzyme.helicobacter pylori flgr activates transcription with sigma54-rna polymerase holoenzyme (sigma54-holoenzyme) from at least five flagellar operons. activators of sigma54-holoenzyme generally bind enhancer sequences located >70 bp upstream of the promoter and contact sigma54-holoenzyme bound at the promoter through dna looping to activate transcription. h. pylori flgr lacks the carboxy-terminal dna-binding domain present in most sigma54-dependent activators. as little as 42 bp of dna upstream of t ...200415231786
molecular characterization of benzimidazole resistance in helicobacter pylori.a family of benzimidazole derivatives (bi) was shown to possess potent and selective activity against helicobacter pylori, although the precise cellular target of the bis is unknown. spontaneous h. pylori mutants were isolated as resistant to a representative bi (compound a). genomic dna was isolated from a bi-resistant mutant, transformed into a bi-sensitive strain, and found to be sufficient to confer bi resistance. the resistance determinant was localized to a 17-kb clone after screening a la ...200415215104
adaptation of campylobacter jejuni nctc11168 to high-level colonization of the avian gastrointestinal tract.the genome sequence of the human pathogen campylobacter jejuni nctc11168 has been determined recently, but studies on colonization and persistence in chickens have been limited due to reports that this strain is a poor colonizer. experimental colonization and persistence studies were carried out with c. jejuni nctc11168 by using 2-week-old light sussex chickens possessing an acquired natural gut flora. after inoculation, nctc11168 initially colonized the intestine poorly. however, after 5 weeks ...200415213117
quinolone-resistant campylobacter infections: risk factors and clinical consequences.we integrated data on quinolone and macrolide susceptibility patterns with epidemiologic and typing data from campylobacter jejuni and c. coli infections in two danish counties. the mean duration of illness was longer for 86 patients with quinolone-resistant c. jejuni infections (median 13.2 days) than for 381 patients with quinolone-sensitive c. jejuni infections (median 10.3 days, p = 0.001). foreign travel, eating fresh poultry other than chicken and turkey, and swimming were associated with ...200415207057
relapsing cellulitis associated with campylobacter coli bacteremia in an agammaglobulinemic patient.campylobacter coli rarely causes bacteremia or extraintestinal infection. we report herein a case of agammaglobulinemia in which cellulitis associated with c. coli bacteremia relapsed after a disease-free interval of >5 years. pulsed field gel electrophoresis revealed that the organisms in this patient were genetically identical, suggesting a latent c. coli infection.200415194845
genotyping of broiler-originated campylobacter jejuni and campylobacter coli isolates using fla typing and random amplified polymorphic dna methods.liver and intestine samples taken from 200 broilers at 20 flocks were inoculated onto preston enrichment broth and agar for selective isolation of campylobacter jejuni and campylobacter coli. the isolates were identified by both conventional and polymerase chain reaction (pcr) methods. campylobacter spp. were identified in 102 of 400 samples (200 liver and 200 intestine), 57 (14.25%) of which were identified as c. jejuni and 45 (11.25%) as c. coli. pcr-restriction fragment length polymorphism (r ...200415193806
in vitro inhibitory activity of chinese leek extract against campylobacter species.three aqueous extracts of dietary materials of chinese leek (leek flower stem, soft leek and green leek) and two other reference extracts of allium plants were used to investigate the antibacterial effects against campylobacter jejuni and campylobacter coli. all the tested strains of campylobacter species were isolated from chickens. the minimum concentration of aqueous leek extracts (ales) required to inhibit the bacterial growth was 2.0 mg/ml. among the plant extracts tested, ales shared the l ...200415193803
characterization of erythromycin resistance in campylobacter coli and campylobacter jejuni isolated from pig offal in new zealand.to determine the level and mechanism(s) of antimicrobial resistance in campylobacter isolates obtained from human and environmental sources from south canterbury, new zealand.200415186451
antimicrobial resistance among enteric pathogens.diarrhea is a major cause of morbidity and mortality in infants and children worldwide. use of antimicrobial therapy in children with bacterial diarrhea involves consideration of advantages and limitations of use of appropriate agents in the general population and in specific hosts. antimicrobial agents for bacterial diarrhea should be prescribed with an appreciation of limitations including antimicrobial resistance. studies from many countries have reported resistance to campylobacter jejuni, c ...200415185189
prevalence and antimicrobial resistance of campylobacter coli isolated from fattening pigs in france.campylobacter are a leading cause of human diarrhea. the usual source of infection is contaminated food, particularly poultry but pork has also been described. the veterinary use of antimicrobial drugs has been suggested to be largely responsible for resistance in human isolates of this zoonotic pathogen. a study was carried out to investigate the occurrence and antimicrobial resistance of campylobacter isolated from french fattening pigs. from march 1998 to june 1999, stomach samples were colle ...200415172691
characterization of a haemolytic phospholipase a(2) activity in clinical isolates of campylobacter concisus.a membrane-bound, haemolytic phospholipase a(2) (pla(2)) activity was detected in clinical strains of campylobacter concisus isolated from children with gastroenteritis. the clinical strains were assigned into two molecular groups (genomospecies) based on pcr amplification of their 23s rdna. this calcium-dependent, heat-stable, haemolytic pla(2) activity was detected in strains from both genomospecies. a crude haemolysin extract (che) was initially prepared from cellular outer-membrane proteins ...200415150326
fluoroquinolone-resistant campylobacter in animal reservoirs: dynamics of development, resistance mechanisms and ecological fitness.thermophilic campylobacter species, including campylobacter jejuni and campylobacter coli, are responsible for foodborne campylobacteriosis in humans and are increasingly resistant to fluoroquinolone (fq) antimicrobials. the therapeutic use of fq antimicrobial agents in food animal production, particularly in poultry, has become a concern for public health, because the practice may promote the emergence of fq-resistant campylobacter that can be transmitted to humans through the food chain. recen ...200315134291
use of the omp50 gene for identification of campylobacter species by pcr.we studied the prevalence of the omp50 gene and the omp50 protein in campylobacter strains. immunodetection assays and dna-dna hybridizations showed that most c. coli strains tested were negative and most c. jejuni and c. lari strains tested were positive. a pcr assay was developed, using the omp50 gene as a species-specific target. we propose a combination of a hippurate test and an omp50 assay to perform identification of campylobacter species.200415131219
longitudinal study of the excretion patterns of thermophilic campylobacter spp. in young pet dogs in denmark.the campylobacter excretion patterns of 26 domestic pet dogs were described in a longitudinal study. the dogs entered the study between 3 and 8 months of age and were monitored until 2 years of age. they were tested monthly for campylobacter carriage in stool samples that were cultured on the campylobacter-selective media cat and modified ccda agar at 37 and 42 degrees c. this study comprised 366 fecal swab samples, of which 278 (76.2%) were found to be campylobacter positive, with the following ...200415131162
molecular characterization of class 1 integrons from irish thermophilic campylobacter spp.in this study a large random collection (n = 378) of irish thermophilic campylobacter isolates were investigated for the presence of integrons, genetic elements associated with the dissemination of antimicrobial resistance.200415128721
dual control of helicobacter pylori heat shock gene transcription by hspr and hrca.the hspr repressor regulates transcription of the groesl, hrca-grpe-dnak, and cbpa-hspr-orf operons of helicobacter pylori. here we show that two of the hspr-regulated operons, namely, the groesl and dnak operons, encoding the major cellular chaperone machineries are also regulated by the h. pylori homologue of the hrca repressor. similarly to the hspr mutation, deletion of the hrca gene also leads to complete derepression of the pgro and phrc promoters. the presence of both hspr and hrca is the ...200415126455
relative contribution of target gene mutation and efflux to fluoroquinolone and erythromycin resistance, in french poultry and pig isolates of campylobacter coli.thirty-eight avian and swine french isolates of campylobacter coli were studied for their mechanisms of co-resistance to fluoroquinolones and erythromycin. a thr86ile modification of gyra, responsible for fluoroquinolone resistance, was found in all the strains. two different levels of resistance to erythromycin (mic of 8-16 or >/=256 mg/l) were observed. a a2075g mutation in the 23s rrna genes was found only in the highly-resistant strains. phe-arg-beta-naphthylamide, an efflux pump inhibitor, ...200415120725
cloning and characterization of the gene encoding the major cell-associated phospholipase a of legionella pneumophila, plab, exhibiting hemolytic activity.legionella pneumophila, the causative agent of legionnaires' disease, is an intracellular pathogen of amoebae, macrophages, and epithelial cells. the pathology of legionella infections involves alveolar cell destruction, and several proteins of l. pneumophila are known to contribute to this ability. by screening a genomic library of l. pneumophila, we found an additional l. pneumophila gene, plab, which coded for a hemolytic activity and contained a lipase consensus motif in its deduced protein ...200415102773
in vitro and in vivo characterization of helicobacter hepaticus cytolethal distending toxin mutants.helicobacter hepaticus expresses a member of the cytolethal distending toxin (cdt) family of bacterial cytotoxins. to investigate the role of cdt in the pathogenesis of h. hepaticus, transposon mutagenesis was used to generate a series of isogenic mutants in and around the cdtabc gene cluster. an h. hepaticus transposon mutant with a disrupted cdtabc coding region no longer produced cdt activity. conversely, a transposon insertion outside of the cluster did not affect the cdt activity. an examin ...200415102759
bacterial pathogen incidences in sludge from swedish sewage treatment plants.this study surveyed the presence of bacterial pathogens in eight swedish sewage treatment plants (stps), with four different treatment methods, focusing on detection of zoonotic bacteria in raw and treated sludge. salmonella spp., listeria monocytogenes, campylobacter coli and jejuni, escherichia coli o157 and indicator bacteria were investigated. samplings were performed from july 2000 to june 2002, resulting in 64 raw sludge samples and 69 treated sludge samples. the samples from raw sludge (6 ...200415087179
direct quantification of campylobacter jejuni and campylobacter lanienae in feces of cattle by real-time quantitative pcr.campylobacter species are fastidious to culture, and the ability to directly quantify biomass in microbiologically complex substrates using real-time quantitative (rtq) pcr may enhance our understanding of their biology and facilitate the development of efficacious mitigation strategies. this study reports the use of nested rtq-pcr to directly quantify campylobacter jejuni and campylobacter lanienae in cattle feces. for c. jejuni, the single-copy mapa gene was selected. for c. lanienae, the thre ...200415066825
development of a multiplex microarray microsystem.a hybrid multiplex microarray microsystem has been developed that consists of 32 individually addressable array reaction chambers, supporting the use of multichannel pipettes for addition of up to 8 samples simultaneously. discrimination between campylobacter jejuni and campylobacter coli bacteria was observed in dna samples containing campylobacter spp., with the same specificity and sensitivity as when compared to a full-size microarray. the spinloaded multiplex microarray microsystem describe ...200415052357
prevalence and characteristics of shiga toxin-producing escherichia coli, salmonella spp. and campylobacter spp. isolated from slaughtered sheep in switzerland.caecum samples collected from 653 slaughtered sheep from two swiss abattoirs were examined. the aim of this study was: (i) to determine the prevalence of shiga toxin-producing escherichia coli (stec), salmonella spp. and campylobacter spp.; (ii) to further characterize isolated strains; and (iii) to discuss the results obtained with their relevance to food safety. the percentage of samples testing positive for stec by a polymerase chain reaction was 29.9%. the prevalence of positive salmonella s ...200415033267
sequence polymorphism in the glycosylation island and flagellins of pseudomonas aeruginosa.a genomic island consisting of 14 open reading frames, orfa to orfn was previously identified in pseudomonas aeruginosa strain pak and shown to be essential for glycosylation of flagellin. dna microarray hybridization analysis of a number of p. aeruginosa strains from diverse origins showed that this island is polymorphic. pcr and sequence analysis confirmed that many p. aeruginosa strains carry an abbreviated version of the island (short island) in which orfd, -e and -h are polymorphic and orfi ...200415028697
emergence of fluoroquinolone resistance in the native campylobacter coli population of pigs exposed to enrofloxacin.the effect of a single 5 day enrofloxacin treatment on the native campylobacter coli population in conventionally weaned 5-week-old pigs was investigated.materials: twelve pigs were split into two groups of six: one group was treated with a therapeutic dose (15 mg/pig/day) of enrofloxacin and the other remained untreated to act as the control. campylobacter coli were isolated from faecal samples and tested for ciprofloxacin resistance by measuring mic values. mutations in the quinolone resistanc ...200415028665
[the role of certain campylobacter types in the etiology of enterocolitis].in recent decades, medical community has increasingly been calling attention to the importance of campylobacter as an disease-causing agent in humans. nowadays, campylobacter jejuni (c. jejuni) is known as the most frequent bacterial cause of diarrhea worldwide. epidemiological differences of the infections caused by campylobacter, present in the developed and the developing countries, are attributed to the differences of the types of virulence. due to the specificity, and the demanding features ...200415022385
occurrence of campylobacter jejuni in pets living with human patients infected with c. jejuni.campylobacter jejuni was recovered from four dogs (11%) and four cats (33%) living with danish human patients infected with c. jejuni. pulsed-field gel electrophoresis (pfge) analysis revealed the occurrence of the same quinolone-resistant strain in a girl and her dog. c. jejuni isolates with closely related (>95% similarity) pfge profiles occurred in humans and pets from different danish counties.200415004120
multiplex pcr assay for differentiation of helicobacter felis, h. bizzozeronii, and h. salomonis.helicobacter felis, helicobacter bizzozeronii, and helicobacter salomonis are frequently found in the gastric mucous membrane of dogs and cats. these large spiral organisms are phylogenetically highly related to each other. their fastidious nature makes it difficult to cultivate them in vitro, hampering traditional identification methods. we describe here a multiplex pcr test based on the trna intergenic spacers and on the urease gene, combined with capillary electrophoresis, that allows discrim ...200415004062
transcriptional phase variation at the flhb gene of pseudomonas putida dot-t1e is involved in response to environmental changes and suggests the participation of the flagellar export system in solvent tolerance.frameshift mutations in a poly(g) track at the flhb gene of pseudomonas putida dot-t1e are responsible for the diminished swimming of this strain on semisolid medium, which contrasts with the high swimming ability of p. putida kt2440, which does not exhibit a poly(g) track at the flhb gene. we previously showed that a mutant lacking flhb was more sensitive to solvents than the wild-type strain (segura et al., j. bacteriol., 183:4127-4133, 2001). in this study, we show that swimming ability corre ...200414996824
optimization of pcr-based methods for rapid detection of campylobacter jejuni, campylobacter coli and yersinia enterocolitica serovar 0:3 in wastewater samples.pcr-based methods were evaluated for their adequacy to assess the removal of pathogens from wastewater samples. for the development and optimization of the methods, samples were taken at two different sites from two different constructed wetlands. campylobacter jejuni/coli and yersinia enterocolitica serogroup 0:3 were selected as model pathogens and enterococcus faecalis as a standard microbiological indicator. the chosen pcr protocols were optimized for wastewater dna extracts in order to obta ...200414975667
distribution and characterization of campylobacter spp. from russian poultry.the distribution of campylobacter spp. on 13 poultry farms (broiler chicken, quail, pheasant, peacock, and turkey) from eight regions (vladimir, vologda, voronezh, kaluga, liptsk, moscow, orenburg, and orel) in russia was surveyed. intestinal materials were plated onto campylobacter-selective medium and plates were incubated microaerobically at 42 degrees c for 24 or 48 h. identification was based on colonial morphology, microscopic examination, and biochemical tests; latex agglutination assays ...200414968953
characterization of campylobacter isolates recovered from clinically healthy pigs and from sporadic cases of campylobacteriosis in humans.campylobacter spp. were recovered from 660 (77.6%) of 850 swine cecal contents at the abattoir and from 24 (8.6%) of 278 specimens from sporadic cases of human diarrhea during the same period in the same geographical area. campylobacter coli represented 95.7% of campylobacter isolates recovered from pigs and 8.3% of those isolated from humans. genetic profiles were determined by pulsed-field gel electrophoresis (pfge) using kpni enzyme to characterize the isolates in combination with phenotypic ...200414968951
routes for campylobacter contamination of poultry meat: epidemiological study from hatchery to slaughterhouse.from april 1998 to march 2000, 18 broiler flocks were followed from the hatchery to the slaughterhouse. campylobacter was not found in the hatchery, 1-day-old chicks or in the rearing house before the arrival of the chicks. the infection of broiler flocks increased continuously during the rearing time, with a total of seven positive flocks at the end of rearing. farms with campylobacter-positive broilers were characterized by the circulation of campylobacter in the environment (puddles, dung hil ...200314959785
simultaneous presence of multiple campylobacter species in dogs.the prevalence of coinfection of campylobacter species in dogs was determined using four isolation methods. in 26% of the positive-testing stools, multiple campylobacter species were identified. the use of multiple isolation methods as well as the time lapse between sampling and processing are important for detection of coinfection.200414766860
comparison of survival of campylobacter jejuni in the phyllosphere with that in the rhizosphere of spinach and radish plants.campylobacter jejuni has been isolated previously from market produce and has caused gastroenteritis outbreaks linked to produce. we have tested the ability of this human pathogen to utilize organic compounds that are present in leaf and root exudates and to survive in the plant environment under various conditions. carbon utilization profiles revealed that c. jejuni can utilize many organic acids and amino acids available on leaves and roots. despite the presence of suitable substrates in the p ...200414766604
genotypic and antibiotic susceptibility characteristics of a campylobacter coli population isolated from dairy farmland in the united kingdom.campylobacter infections are the most common cause of bacterial enteritis in humans, and nearly 8% of such infections are caused by campylobacter coli. most studies have concentrated on campylobacter jejuni, frequently isolated from intensively farmed poultry and livestock production units, and few studies have examined the spread and relatedness of campylobacter across a range of geographical and host boundaries. systematic sampling of a 100-km2 area of mixed farmland in northwest england yield ...200414766560
proteomic analysis of the sarcosine-insoluble outer membrane fraction of helicobacter pylori strain 26695.helicobacter pylori causes gastroduodenal disease, which is mediated in part by its outer membrane proteins (omps). to identify omps of h. pylori strain 26695, we performed a proteomic analysis. a sarcosine-insoluble outer membrane fraction was resolved by two-dimensional electrophoresis with immobilized ph gradient strips. most of the protein spots, with molecular masses of 10 to 100 kda, were visible on the gel in the alkaline pi regions (6.0 to 10.0). the proteome of the omps was analyzed by ...200414761989
gastroenteritis in nf-kappab-deficient mice is produced with wild-type camplyobacter jejuni but not with c. jejuni lacking cytolethal distending toxin despite persistent colonization with both strains.campylobacter jejuni continues to be a leading cause of bacterial enteritis in humans. however, because there are no readily available animal models to study the pathogenesis of c. jejuni-related diseases, the significance of potential virulence factors, such as cytolethal distending toxin (cdt), in vivo are poorly understood. mice deficient in nf-kappab subunits (p50(-/-) p65(+/-)) in a c57bl/129 background are particularly susceptible to colitis induced by another enterohepatic microaerobe, he ...200414742559
a survey of campylobacter species shed in faeces of beef cattle using polymerase chain reaction.a polymerase chain reaction (pcr)-based survey of campylobacters associated with faeces collected from 382 beef cattle was undertaken. to ensure the removal of pcr inhibitors present in faeces and determine if adequate extraction was achieved, faeces were seeded with internal control dna (i.e., dna designed to amplify with the campylobacter genus primer set, but provide a smaller amplicon) before the extraction procedure. in only two samples (0.5%) were the internal control or campylobacter genu ...200314735214
the neuc protein of escherichia coli k1 is a udp n-acetylglucosamine 2-epimerase.the k1 capsule is an essential virulence determinant of escherichia coli strains that cause meningitis in neonates. biosynthesis and transport of the capsule, an alpha-2,8-linked polymer of sialic acid, are encoded by the 17-kb kps gene cluster. we deleted neuc, a k1 gene implicated in sialic acid synthesis, from the chromosome of ev36, a k-12-k1 hybrid, by allelic exchange. exogenously added sialic acid restored capsule expression to the deletion strain (deltaneuc), confirming that neuc is nece ...200414729696
fluorescent amplified fragment length polymorphism genotyping of campylobacter jejuni and campylobacter coli strains and its relationship with host specificity, serotyping, and phage typing.fluorescent amplified fragment length polymorphism (faflp) analysis was applied to 276 campylobacter jejuni strains and 87 campylobacter coli strains isolated from humans, pigs, cattle, poultry, and retail meats to investigate whether certain faflp genotypes of c. jejuni and c. coli are associated with a particular host and to determine the degree of association between faflp-defined genotypes and heat-stable serotypes and/or phage types. within c. coli, the poultry strains clustered separately ...200414715757
campylobacter spp., giardia spp., cryptosporidium spp., noroviruses, and indicator organisms in surface water in southwestern finland, 2000-2001.a total of 139 surface water samples from seven lakes and 15 rivers in southwestern finland were analyzed during five consecutive seasons from autumn 2000 to autumn 2001 for the presence of various enteropathogens (campylobacter spp., giardia spp., cryptosporidium spp., and noroviruses) and fecal indicators (thermotolerant coliforms, escherichia coli, clostridium perfringens, and f-rna bacteriophages) and for physicochemical parameters (turbidity and temperature); this was the first such systema ...200414711629
antimicrobial susceptibility trends in campylobacter jejuni and campylobacter coli isolated from a rural egyptian pediatric population with diarrhea.comparative and trend analysis was conducted on annual prevalence of antimicrobial susceptibility among campylobacter jejuni and campylobacter coli recovered from rural egyptian children from 1995 through 2000. c. jejuni and c. coli demonstrated significant decreasing trends in ciprofloxacin susceptibility over the study period (p < 0.001 for both). in general, c. coli demonstrated a higher degree of susceptibility than c. jejuni, however, there was no statistical difference (p = 0.2) comparing ...200314711482
cecal colonization of chicks by bovine-derived strains of campylobacter.campylobacter jejuni and campylobacter coli strains were isolated from feces of dairy cattle at farms with no known problem due to campylobacteria. farms were located in the northeast, desert southwest, and pacific west. twenty isolates were identified by ribotyping with a riboprinter. the ability of these bovine isolates to colonize the ceca of chicks was determined by challenge inoculation and reisolation of the challenge strain from the ceca at 1 and 2 wk after challenge. isolates recovered f ...200314708992
l-serine catabolism via an oxygen-labile l-serine dehydratase is essential for colonization of the avian gut by campylobacter jejuni.campylobacter jejuni is a microaerophilic, asaccharolytic bacterium. the identity of the carbon and energy sources used by c. jejuni in vivo is unknown, but the genome sequence of strain nctc11168 indicates the presence of genes for catabolism of a limited range of amino acids, including serine. specific omission of l-serine from a defined medium containing a mixture of amino acids led to a dramatic decrease in cell yields. as c. jejuni does not have a biosynthetic serine requirement, this suppo ...200414688104
[acute diarrhea in children less than 3 years of age: enteropathogens isolated in patient's stools, compared with a control group]objectives: to observe the occurrence of different etiological agents of acute diarrhea (ad) in stool specimens of patients and children in a control group. material and methods: 100 children less than three years of age with ad were studied as well as 100 controls, between november 1993 and may 1994. stool specimens were collected in both groups and the following enteropathogens were searched for: rotavirus, escherichia coli (epec, etec, eiec, ehec), salmonella sp, shigella sp, campylobacter je ...199914685548
applicability of a rapid duplex real-time pcr assay for speciation of campylobacter jejuni and campylobacter coli directly from culture plates.a rapid duplex real-time polymerase chain reaction (pcr) assay for speciation of campylobacter jejuni and campylobacter coli using the abi prism 7700 sequence detection system (applied biosystems) was developed based on two of the genes used in a conventional multiplex pcr. a rapid turnaround time of 3 h was achieved with the use of boiled cell lysates. applicability of the assay was tested with 6015 random campylobacter strains referred to the campylobacter reference unit, with 97.6% being iden ...200314680705
risk factors associated with campylobacter jejuni infections in curaçao, netherlands antilles.a steady increase in the incidence of guillain-barré syndrome (gbs) with a seasonal preponderance, almost exclusively related to campylobacter jejuni, and a rise in the incidence of laboratory-confirmed campylobacter enteritis have been reported from curaçao, netherlands antilles. we therefore investigated possible risk factors associated with diarrhea due to epidemic c. jejuni. typing by pulsed-field gel electrophoresis identified four epidemic clones which accounted for almost 60% of the infec ...200314662945
risk factors for antibiotic resistance in campylobacter spp. isolated from raw poultry meat in switzerland.the world-wide increase of foodborne infections with antibiotic resistant pathogens is of growing concern and is designated by the world health organization as an emerging public health problem. thermophilic campylobacter have been recognised as a major cause of foodborne bacterial gastrointestinal human infections in switzerland and in many other countries throughout the world. poultry meat is the most common source for foodborne cases caused by campylobacter. because all classes of antibiotics ...200314662013
avian reservoirs and zoonotic potential of the emerging human pathogen helicobacter canadensis.a polyphasic identification approach was used to investigate the taxonomic position of campylobacter-like isolates recovered from barnacle geese (branta leucopsis) and canada geese (branta candensis). seven strains were selected from a collection of 21 isolates and analyzed by extensive phenotypic testing; four strains were characterized by 16s rrna gene sequence analysis. the results clearly identified the bird isolates as helicobacter canadensis, recently described as an emerging human pathoge ...200314660407
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