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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
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
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
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
longitudinal study of campylobacter jejuni bacteriophages and their hosts from broiler chickens.a longitudinal study of bacteriophages and their hosts was carried out at a broiler house that had been identified as having a population of campylobacter-specific bacteriophages. cloacal and excreta samples were collected from three successive broiler flocks reared in the same barn. campylobacter jejuni was isolated from each flock, whereas bacteriophages could be isolated from flocks 1 and 2 but were not isolated from flock 3. the bacteriophages isolated from flocks 1 and 2 were closely relate ...200415240258
identification of bacterial populations in dairy wastewaters by use of 16s rrna gene sequences and other genetic markers.hydraulic flush waste removal systems coupled to solid/liquid separators and circulated treatment lagoons are commonly utilized to manage the large amounts of animal waste produced on high-intensity dairy farms. although these systems are common, little is known about the microbial populations that inhabit them or how they change as they traverse the system. using culture-based and non-culture-based methods, we characterized the microbial community structure of manure, water from the separator p ...200415240310
multiplex pcr assay for detection of streptococcus suis species and serotypes 2 and 1/2 in tonsils of live and dead pigs.a pcr assay was developed for the detection of streptococcus suis serotypes 2 and 1/2. this multiplex pcr is based on the amplification of the gene coding for 16s rrna of s. suis and on the amplification of the cps2j gene coding for the capsule of s. suis serotypes 2 and 1/2. an internal control was constructed and added in this test to monitor the efficiency of amplification in each reaction. to evaluate the specificity of the test, 31 strains of other bacterial species related to s. suis or is ...200415243078
campylobacter colonization of sibling turkey flocks reared under different management conditions.uncertainty exists concerning the key factors contributing to campylobacter colonization of poultry, especially the possible role of vertical transmission from breeder hens to young birds. a longitudinal study of campylobacter colonization was performed in two sibling pairs of turkey flocks (four flocks total). each pair of sibling flocks shared breeder hen populations and was obtained from the same hatchery. one flock of each pair was grown on a commercial farm, and the other was grown in an in ...200415270502
campylobacter prevalence in lactating dairy cows in the united states.the objective of the present study was to determine the prevalence of intestinal campylobacter in lactating dairy cows from various regions of the united states. participating commercial dairy farms were chosen at random and were part of a national survey to determine e. coli o157:h7 and salmonella prevalence in dairy cows. farms had no previous history of campylobacter problems. fecal samples were collected rectally from 720 cows on farms in the northeast (four farms), in the desert southwest ( ...200415270504
a real-time multiplexed pcr assay for rapid detection and differentiation of campylobacter jejuni and campylobacter coli.campylobacter species are the leading agents of bacterial gastroenteritis worldwide. c. jejuni and c. coli together are responsible for more than 95% of all cases of campylobacter-induced diarrheal disease in the united states. detection of campylobacteria in clinical samples by conventional culture is problematic and slow due to their complex taxonomy, fastidious growth requirements, and biochemical inertness. the current study describes a rapid, sensitive, and specific real-time polymerase cha ...200415271389
helicobacter pylori induces apoptosis of human monocytes but not monocyte-derived dendritic cells: role of the cag pathogenicity island.monocytes are circulating precursors of the dendritic cell subset, professional antigen-presenting cells with a unique ability to initiate the innate and adaptive immune response. in this study, we have investigated the effects of wild-type helicobacter pylori strains and their isogenic mutants with mutations in known bacterial virulence factors on monocytes and monocyte-derived dendritic cells. we show that h. pylori strains induce apoptosis of human monocytes by a mechanism that is dependent o ...200415271906
occurrence of campylobacter in retail foods in ireland.a surveillance study was carried out to determine the prevalence of campylobacter in a range of retail foods purchased in three irish cities over a 20-month period between march 2001 and october 2002. in total 2391 food samples were analysed during this period. campylobacter was isolated from 444 raw chicken (49.9%), 33 turkey (37.5%) and 11 duck samples (45.8%). lower isolation rates of 7/221 (3.2%), 10/197 (5.1%) and 31/262 (11.8%) were observed for raw beef, pork and lamb, respectively. one s ...200415282123
the pattern and kinetics of substrate metabolism of campylobacter jejuni and campylobacter coli.the main aim was to investigate the patterns and kinetics of substrate oxidation by campylobacter jejuni and c. coli.200415287872
role of an inducible single-domain hemoglobin in mediating resistance to nitric oxide and nitrosative stress in campylobacter jejuni and campylobacter coli.campylobacter jejuni expresses two hemoglobins, each of which exhibits a heme pocket and structural signatures in common with vertebrate and plant globins. one of these, designated cgb, is homologous to vgb from vitreoscilla stercoraria and does not possess the reductase domain seen in the flavohemoglobins. a cgb-deficient mutant of c. jejuni was hypersensitive to nitrosating agents (s-nitrosoglutathione [gsno] or sodium nitroprusside) and a nitric oxide-releasing compound (spermine nonoate). th ...200415292134
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
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
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
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
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
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
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
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
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
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
[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
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
genotypic and antibiotic susceptibility characteristics of a campylobacter coli population isolated from dairy farmland in the united kingdom.campylobacter infections are the most common cause of bacterial enteritis in humans, and nearly 8% of such infections are caused by campylobacter coli. most studies have concentrated on campylobacter jejuni, frequently isolated from intensively farmed poultry and livestock production units, and few studies have examined the spread and relatedness of campylobacter across a range of geographical and host boundaries. systematic sampling of a 100-km2 area of mixed farmland in northwest england yield ...200414766560
comparison of survival of campylobacter jejuni in the phyllosphere with that in the rhizosphere of spinach and radish plants.campylobacter jejuni has been isolated previously from market produce and has caused gastroenteritis outbreaks linked to produce. we have tested the ability of this human pathogen to utilize organic compounds that are present in leaf and root exudates and to survive in the plant environment under various conditions. carbon utilization profiles revealed that c. jejuni can utilize many organic acids and amino acids available on leaves and roots. despite the presence of suitable substrates in the p ...200414766604
simultaneous presence of multiple campylobacter species in dogs.the prevalence of coinfection of campylobacter species in dogs was determined using four isolation methods. in 26% of the positive-testing stools, multiple campylobacter species were identified. the use of multiple isolation methods as well as the time lapse between sampling and processing are important for detection of coinfection.200414766860
campylobacter spp., giardia spp., cryptosporidium spp., noroviruses, and indicator organisms in surface water in southwestern finland, 2000-2001.a total of 139 surface water samples from seven lakes and 15 rivers in southwestern finland were analyzed during five consecutive seasons from autumn 2000 to autumn 2001 for the presence of various enteropathogens (campylobacter spp., giardia spp., cryptosporidium spp., and noroviruses) and fecal indicators (thermotolerant coliforms, escherichia coli, clostridium perfringens, and f-rna bacteriophages) and for physicochemical parameters (turbidity and temperature); this was the first such systema ...200414711629
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
antimicrobial resistance of campylobacter jejuni and campylobacter coli isolates in japan. 200415499812
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
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
[incidence of the virulence markers iam in campylobacter jejuni and campylobacter coli strains isolated from poultry carcases].previously found dna sequence (iam), correlated with the invasiveness of campylobacter strains, became a starting point for present investigation. main goal of this study was to isolate number of campylobacter strains from chicken carcasses, to determine their taxonomic position and to establish the presence of iam sequence in their genoms. it was found, that invasion associated marker is present in all campylobacter coli strains and in majority but not all campylobacter jejuni. this may confirm ...200419097580
comparison of electrolyzed oxidizing water with other antimicrobial interventions to reduce pathogens on fresh pork.to date, the effectiveness of electrolyzed oxidizing (eo) water against bacteria associated with fresh pork has not been determined. using a hand-held, food-grade garden sprayer, distilled water (w), chlorinated water (cl; 25 ppm), 2% lactic acid (la), acidic eo water (eoa), or "aged" acidic eo water (aeoa; stored at 4 °c for 24 h) was sprayed (15 s) onto pork bellies inoculated with feces containing listeria monocytogenes (lm), salmonella typhimurium (st), and campylobacter coli (cc). remaining ...200422062415
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
campylobacter in food animals and humans in northern thailand.cross-sectional, longitudinal, and case-control studies were conducted to describe the epidemiology of campylobacter in chickens, swine, dairy cows, farm workers, nonfarm residents, and children with diarrhea. samples were collected in chiang mai and lamphung provinces of northern thailand from 2000 through 2003. a total of 2,360 samples were processed. results from the cross-sectional study indicated that the prevalences of campylobacter in chickens at the farm, slaughterhouse, and market were ...200516355821
prevalence and antimicrobial resistance of campylobacter in antimicrobial-free and conventional pig production systems.the objectives of this study were to determine and compare the prevalence and antimicrobial resistance of campylobacter species in swine reared in conventional and antimicrobial-free (abf) production systems. campylobacter coli was the predominant species, with 1,459 isolates (99%) in the study. we found significantly higher prevalence of c. coli on the abf farms (77.3%) than on the conventional farms (27.6%) among pigs at the nursery stage (p < 0.001). at slaughter, we found significantly highe ...200516300080
multiplex pcr for identification of campylobacter coli and campylobacter jejuni from pure cultures and directly on stool samples.a multiplex-pcr method, specifically designed for application in routine diagnostic laboratories, was developed for the detection of campylobacter coli and campylobacter jejuni. primers were directed towards the following loci: the hippuricase gene (hipo) characteristic of c. jejuni, a sequence partly covering an aspartokinase gene characteristic of c. coli, and a universal 16s rdna gene sequence serving as an internal positive control for the pcr. the method was tested on 47 c. coli strains and ...200516192435
campylobacter coli in swine production: antimicrobial resistance mechanisms and molecular epidemiology.the aim of this study was to determine antimicrobial resistance, to evaluate and compare the use of two genotyping methods for molecular epidemiology purposes, and to determine the genotypic diversity of campylobacter coli of porcine origin. a total of 100 c. coli isolates from swine were tested for susceptibility to six antimicrobials using the agar dilution method and genotyped using two high-resolution fingerprinting approaches: multilocus sequence typing (mlst) and pulsed-field gel electroph ...200516272508
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
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
delineation of campylobacter concisus genomospecies by amplified fragment length polymorphism analysis and correlation of results with clinical data.campylobacter concisus has been as frequently isolated from human diarrhea as the important enteropathogen campylobacter jejuni, but it also occurs in the feces of healthy individuals. the role of c. concisus in human disease has been difficult to determine, since the species comprises at least two phenotypically indistinguishable but genetically distinct taxa (i.e., genomospecies) that may vary in pathogenicity. we examined 62 c. concisus strains by amplified fragment length polymorphism (aflp) ...200516207968
occurrence of campylobacter species in poultry forms in lagos area of nigeria.samples of poultry droppings were collected from fifty poultry farms in lagos area of nigeria. campylobacter species were isolated from serially diluted samples using bolton selective enrichment medium under microaerophilic condition at 42 degrees c. samples of water, both treated and untreated used in the farms were also analysed in the same manner. fifteen campylobacter strains were isolated from the droppings. all the strains were identified using biochemical characteristics differentiating c ...200516334275
the heterogeneity of campylobacter jejuni and campylobacter coli strains isolated from healthy cattle.to identify campylobacters isolated from clinically healthy cattle at species level by a multiplex polymerase chain reaction (m-pcr). the heterogeneity among campylobacter jejuni and campylobacter coli isolates was also investigated by using a restriction fragment length polymorphism (rflp) analysis of flagellin (flaa) gene.200516238642
dissimilatory metabolism of nitrogen oxides in bacteria: comparative reconstruction of transcriptional networks.bacterial response to nitric oxide (no) is of major importance since no is an obligatory intermediate of the nitrogen cycle. transcriptional regulation of the dissimilatory nitric oxides metabolism in bacteria is diverse and involves fnr-like transcription factors hcpr, dnr, and nnrr; two-component systems narxl and narqp; no-responsive activator norr; and nitrite-sensitive repressor nsrr. using comparative genomics approaches, we predict dna-binding motifs for these transcriptional factors and ...200516261196
microbial health risk posed by table eggs in trinidad.a survey of the microbial quality of table eggs sold in trinidad was conducted. for 23 poultry layer farms each visited twice approximately 1 month apart, 25 pooled eggs constituted a composite sample, for 14 shopping malls each visited twice approximately 1 month apart, six pooled eggs made a composite sample and for a total of 102 other retailers across the country each visited once over a 4-month period, six pooled eggs constituted a composite sample. swabs of egg shells and egg content were ...200516274501
the importance of campylobacter coli in human campylobacteriosis: prevalence and genetic characterization.the primary aim of this study was to detect and genotype campylobacter coli strains from humans over a period of one year from november 2002 to october 2003. campylobacter spp. were isolated from patients with symptoms of enteric infection. amplified fragment length polymorphism (aflp) analysis was used to identify the genetic diversity of c. coli strains by cluster analysis. a total of 18.6% of all campylobacter isolates were identified as c. coli. these data show, that c. coli is indeed of imp ...200516274505
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
[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
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
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
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
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
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
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
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
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
agricultural antibiotics and human health. 200515984910
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
factors affecting the pressure resistance of some campylobacter species.to compare pressure resistance between strains of campylobacter jejuni, campylobacter coli, campylobacter lari and campylobacter fetus, and to investigate the effect of suspending medium on pressure resistance of sensitive and more resistant strains.200516162138
acid-induced activation of the urease promoters is mediated directly by the arsrs two-component system of helicobacter pylori.the nickel-containing enzyme urease is an essential colonization factor of the human gastric pathogen helicobacter pylori which enables the bacteria to survive the low-ph conditions of the stomach. transcription of the urease genes is positively controlled in response to increasing concentrations of nickel ions and acidic ph. here we demonstrate that acid-induced transcription of the urease genes is mediated directly by the arsrs two-component system. footprint analyses identify binding sites of ...200516177315
genomic diversity of campylobacter coli and campylobacter jejuni isolates recovered from free-range broiler farms and comparison with isolates of various origins.in many industrialized countries, the incidence of campylobacteriosis exceeds that of salmonellosis. campylobacter bacteria are transmitted to humans mainly in food, especially poultry meat products. total prevention of campylobacter colonization in broiler flocks is the best way to reduce (or eliminate) the contamination of poultry products. the aim of this study was to establish the sources and routes of contamination of broilers at the farm level. molecular typing methods (dna macrorestrictio ...200516204541
differentiation of campylobacter populations as demonstrated by flagellin short variable region sequences.the dna sequence of the flaa short variable region (svr) was used to analyze a random population of campylobacter isolates to investigate the weakly clonal population structure of members of the genus. the svr sequence from 197 strains of c. jejuni and c. coli isolated from humans, bovine, swine, and chickens identified a group of 43 strains containing disparate short variable region sequences compared to the rest of the population. this group contains both c. jejuni and c. coli strains but disp ...200516204559
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
campylobacter coli: prevalence and antimicrobial resistance in antimicrobial-free (abf) swine production systems.to 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
neither hippurate-negative brachyspira pilosicoli nor brachyspira pilosicoli type strain caused diarrhoea in early-weaned pigs by experimental infection.a hippurate-negative biovariant of brachyspira pilosicoli (b. pilosicolihipp-) is occasionally isolated in diarrhoeic pigs in finland, often concomitantly with hippurate-positive b. pilosicoli or lawsonia intracellularis. we studied pathogenicity of b. pilosicolihipp- with special attention paid to avoiding co-infection with other enteric pathogens. pigs were weaned and moved to barrier facilities at the age of 11 days. at 46 days, 8 pigs were inoculated with b. pilosicolihipp- strain br1622, 8 ...200516398337
measurement of the viability of lawsonia intracellularis.the objective of this study was to develop and test both a flow cytometry method (fcm) and a direct count method (dcm) that both use fluorescent stains to determine the viability of lawsonia intracellularis (li), an obligate intracellular bacterium and the cause of proliferative enteropathy (pe) in pigs and other animal species. live li were passaged in cell culture and harvested from infected mccoy cells. dead li were prepared by exposing live li to 70% isopropyl alcohol for 30 min. seven sampl ...200516479724
characterization of a cmeabc operon in a quinolone-resistant campylobacter coli isolate of irish origin.in this study, a tripartite-operon-encoding efflux system together with its regulatory gene was characterized in an irish campylobacter coli isolate cit-382 showing high-level resistance to nalidixic acid and ciprofloxacin. sequence comparisons revealed significant homology between c. coli and the cmeabc operon of campylobacter jejuni. conservation of functional sequence domains and motifs were noted among c. coli and similar operons in unrelated organisms. a transcriptional regulatory gene cmer ...200516359189
mortality following campylobacter infection: a registry-based linkage study.campylobacteriosis is one of the most commonly identified causes of bacterial diarrheal disease and a common cause of gastroenteritis in travellers from developed nations. despite the widespread occurrence, there is little information on campylobacter mortality.200516162289
comparative phylogenomics of the food-borne pathogen campylobacter jejuni reveals genetic markers predictive of infection source.campylobacter jejuni is the predominant cause of bacterial gastroenteritis worldwide, but traditional typing methods are unable to discriminate strains from different sources that cause disease in humans. we report the use of genomotyping (whole-genome comparisons of microbes using dna microarrays) combined with bayesian-based algorithms to model the phylogeny of this major food-borne pathogen. in this study 111 c. jejuni strains were examined by genomotyping isolates from humans with a spectrum ...200516230626
epidemiology of campylobacter jejuni and campylobacter coli infections in the zenica--doboj canton, bosnia and herzegovina--a laboratory based surveillance in the 1999-2001 period.previous studies in the zenica--doboj canton, bosnia and herzegovina, indicated some different epidemiological features of campylobacter infections and high degree of antimicrobial resistance. therefore, it was important to investigate epidemiology of campylobacter jejuni and campylobacter coli infections by demographic features and antimicrobial resistance in the 1999-2001 period. a total number of 40 (75.5%) c. jejuni and 13 (24.5%) c. coli non-repeated clinical isolates were analyzed. more th ...200516417178
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
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
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
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
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
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
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 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
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
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
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
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
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
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
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 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
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 samples.to 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
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
[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
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
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