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effect of incubation temperature on isolation of campylobacter jejuni genotypes from foodstuffs enriched in preston broth.preston broth and agar incubated at either 37 or 42 degrees c have been widely used to isolate campylobacters from foodstuffs. the consequences of using either incubation temperature were investigated. retail packs of raw chicken (n = 24) and raw lamb liver (n = 30) were purchased. samples were incubated in preston broth at 37 and 42 degrees c and then streaked onto preston agar and incubated as before. two campylobacter isolates per treatment were characterized. poultry isolates were genotyped ...200312902254
description of a "phoenix" phenomenon in the growth of campylobacter jejuni at temperatures close to the minimum for growth.when campylobacter jejuni cultures that had been grown in broth at 39 degrees c were subcultured into fresh medium at 30 degrees c, there was a transient period of growth followed by a decline in viable-cell numbers before growth resumed once more. we propose that this complex behavior is the net effect of the growth of inoculum cells followed by a loss of viability due to oxidative stress and the subsequent emergence of a spontaneously arising mutant population that takes over the culture.200312902294
molecular structure and evolution of the conjugative multiresistance plasmid pre25 of enterococcus faecalis isolated from a raw-fermented sausage.plasmid pre25 from enterococcus faecalis transfers resistances against kanamycin, neomycin, streptomycin, clindamycin, lincomycin, azithromycin, clarithromycin, erythromycin, roxithromycin, tylosin, chloramphenicol, and nourseothricin sulfate by conjugation in vitro to e. faecalis jh2-2, lactococcus lactis bu2, and listeria innocua l19. its nucleotide sequence of 50237 base pairs represents the largest, fully sequenced conjugative multiresistance plasmid of enterococci (plasmid 46 (2001) 170). t ...200314597005
molecular typing of campylobacter jejuni isolates involved in a neonatal outbreak indicates nosocomial transmission.genotypic typing by restriction fragment length polymorphism and pulsed-field gel electrophoresis showed that two neonates in a neonatal ward were infected with the same campylobacter jejuni strain. isolates from the mother and brother of the index patient were identical to each other but distinct from the neonatal type. genotyping results therefore suggested that the neonatal c. jejuni infection was nosocomial in origin.200312904420
hazards of healthy living: bottled water and salad vegetables as risk factors for campylobacter infection. 200314609455
characterization of waterborne outbreak-associated campylobacter jejuni, walkerton, ontario. 200314609457
comparison of human and porcine strains of campylobacter coli. 200312930063
in vitro activities of new fluoroquinolones against campylobacter jejuni and campylobacter coli isolates obtained from humans in 1980 to 1982 and 1997 to 2001.the antibacterial activities of three newly developed fluoroquinolones (gatifloxacin, levofloxacin, and moxifloxacin) against a total of 307 gastrointestinal human isolates of campylobacter jejuni and campylobacter coli collected during 1980 to 1982 and 1997 to 2001 were examined and compared to those of ciprofloxacin and the unrelated antibacterial agents, clarithromycin, erythromycin, and tetracycline by using the agar plate dilution method. all of the fluoroquinolones exhibited a good activit ...200312936999
development of a sensitive dna microarray suitable for rapid detection of campylobacter spp.campylobacter is the most common cause of human acute bacterial gastroenteritis worldwide, widely distributed and isolated from human clinical samples as well as from many other different sources. to comply with the demands of consumers for food safety, there is a need for development of a rapid, sensitive and specific detection method for campylobacter. in this study, we present the development of a novel sensitive dna-microarray based detection method, evaluated on campylobacter and non-campyl ...200312944122
natural transformation of campylobacter jejuni requires components of a type ii secretion system.the human pathogen campylobacter jejuni is one of more than 40 naturally competent bacterial species able to import macromolecular dna from the environment and incorporate it into their genomes. however, in c. jejuni little is known about the genes involved in this process. we used random transposon mutagenesis to identify genes that are required for the transformation of this organism. we isolated mutants with insertions in 11 different genes; most of the mutants are affected in the dna uptake ...200312949093
prevalence of campylobacter within a swine slaughter and processing facility.in this work, the occurrence of campylobacter in a swine slaughter and processing facility was studied. thirty composite carcass samples, representing 360 swine carcasses, were taken immediately after exsanguination, immediately after polishing, after the final wash, and after overnight chilling at 2 degrees c. thirty matching composite rectal samples were also taken immediately after exsanguination, and 60 nonmatching individual colon samples were collected from the same lot of swine during evi ...200314503704
usefulness of the microseq 500 16s ribosomal dna-based bacterial identification system for identification of clinically significant bacterial isolates with ambiguous biochemical profiles.due to the inadequate automation in the amplification and sequencing procedures, the use of 16s rrna gene sequence-based methods in clinical microbiology laboratories is largely limited to identification of strains that are difficult to identify by phenotypic methods. in this study, using conventional full-sequence 16s rrna gene sequencing as the "gold standard," we evaluated the usefulness of the microseq 500 16s ribosomal dna (rdna)-based bacterial identification system, which involves amplifi ...200312734240
disinfectant susceptibility testing of avian and swine campylobacter isolates by a filtration method.the susceptibility testing of disinfectants against campylobacter jejuni and campylobacter coli strains from broilers and pigs was investigated. the filtration method european standard en 1040 was adapted to campylobacter cultures and validated with reference strains. two disinfectants were tested: 1% benzalkonium chloride active matter, as quaternary ammonium compound, and 0.63% sodium hypochlorite as chlorine-releasing agent. both disinfectants were effective against the 34 campylobacter strai ...200314516706
species-specific identification of campylobacters by partial 16s rrna gene sequencing.species-specific identification of campylobacters is problematic, primarily due to the absence of suitable biochemical assays and the existence of atypical strains. 16s rrna gene (16s rdna)-based identification of bacteria offers a possible alternative when phenotypic tests fail. therefore, we evaluated the reliability of 16s rdna sequencing for the species-specific identification of campylobacters. sequence analyses were performed by using almost 94% of the complete 16s rrna genes of 135 phenot ...200312791878
microarray-based identification of thermophilic campylobacter jejuni, c. coli, c. lari, and c. upsaliensis.dna microarrays are an excellent potential tool for clinical microbiology, since this technology allows relatively rapid identification and characterization of microbial and viral pathogens. in the present study, an oligonucleotide microarray was developed and used for the analysis of thermophilic campylobacter spp., the primary food-borne pathogen in the united states. we analyzed four campylobacter species: campylobacter jejuni, c. coli, c. lari, and c. upsaliensis. our assay relies on the pcr ...200312958228
the complete genome sequence of the carcinogenic bacterium helicobacter hepaticus.helicobacter hepaticus causes chronic hepatitis and liver cancer in mice. it is the prototype enterohepatic helicobacter species and a close relative of helicobacter pylori, also a recognized carcinogen. here we report the complete genome sequence of h. hepaticus atcc51449. h. hepaticus has a circular chromosome of 1,799,146 base pairs, predicted to encode 1,875 proteins. a total of 938, 953, and 821 proteins have orthologs in h. pylori, campylobacter jejuni, and both pathogens, respectively. h. ...200312810954
antimicrobial resistance in campylobacter from broilers: association with production type and antimicrobial use.the isolation and antimicrobial resistance of campylobacter jejuni and campylobacter coli strains from broilers arriving in french slaughterhouses, were analysed according to production types (i.e. standard, export or free-range) and antimicrobial (i.e. coccidiostats, growth promoters or therapeutic agents) administration in flocks. prevalence was 56.6% in standard, 51.3% in export and 80.0% in free-range broilers. three hundred and ninety-three strains were identified. two-thirds of the strains ...200314559174
flagellin glycosylation island in pseudomonas syringae pv. glycinea and its role in host specificity.the deduced amino acid sequences of the flagellins of pseudomonas syringae pv. tabaci and p. syringae pv. glycinea are identical; however, their abilities to induce a hypersensitive reaction are clearly different. the reason for the difference seems to depend on the posttranslational modification of the flagellins. to investigate the role of this posttranslational modification in the interactions between plants and bacterial pathogens, we isolated genes that are potentially involved in the postt ...200314594840
diversity and succession of the intestinal bacterial community of the maturing broiler chicken.the diversity of bacterial floras in the ilea and ceca of chickens that were fed a vegetarian corn-soy broiler diet devoid of feed additives was examined by analysis of 1,230 partial 16s rrna gene sequences. nearly 70% of sequences from the ileum were related to those of lactobacillus, with the majority of the rest being related to clostridiaceae (11%), streptococcus (6.5%), and enterococcus (6.5%). in contrast, clostridiaceae-related sequences (65%) were the most abundant group detected in the ...200314602645
production of cytolethal distending toxins by pathogenic escherichia coli strains isolated from human and animal sources: establishment of the existence of a new cdt variant (type iv).three types of cytolethal distending toxin (cdt), namely, cdt-i, cdt-ii, and cdt-iii, have been described in escherichia coli. using primers designed for the detection of sequences common to the cdtb genes, we analyzed by pcr a set of 21 cdt-producing e. coli strains of intestinal and extraintestinal origins isolated from human and different animal species in several european countries and in the united states. on the basis of the existing differences in the cdtb genes, cdt-i-, cdt-ii-, and cdt- ...200312958258
occurrence and resistance to antibiotics of campylobacter jejuni and campylobacter coli in animals and meat in northeastern italy.a study was carried out in northeastern italy during 2000 and 2001 to investigate the occurrence of campylobacter jejuni and campylobacter coli in animals, cattle, pigs, and broilers, and raw meat, beef, pork, and chicken. campylobacter spp. were detected in 53.9% of the cattle, 63.5% of the pigs, and 82.9% of the broilers examined. chicken meat was frequently contaminated (81.3%), while lower rates were found in pork meat (10.3%) and beef (1.3%). the resistance to antibiotics of the strains was ...200312593931
resistance to quinolones in campylobacter jejuni and campylobacter coli from danish broilers at farm level.to investigate the prevalence of quinolone resistance among campylobacter jejuni and camp. coli isolates from danish poultry at the farm level, as well as for the whole country.200312492931
pcr detection of seven virulence and toxin genes of campylobacter jejuni and campylobacter coli isolates from danish pigs and cattle and cytolethal distending toxin production of the isolates.to study the prevalence of seven virulence and toxin genes, and cytolethal distending toxin (cdt) production of campylobacter jejuni and c. coli isolates from danish pigs and cattle.200312752808
antimicrobial resistance of campylobacter jejuni subsp. jejuni strains isolated from humans in 1998 to 2001 in montréal, canada.the rates of resistance of 51 to 72 human strains of campylobacter jejuni subsp. jejuni isolated annually from 1998 to 2001 in montréal, québec, canada, varied from 1 to 12% for erythromycin, 43 to 68% for tetracycline, and 10 to 47% for ciprofloxacin. in the last years of the study, there was a significant increase in the rate of resistance to ciprofloxacin (p = 0.00003) but not in the rate of resistance to erythromycin (p = 0.056) or tetracycline (p = 0.095) compared to the rate obtained in th ...200312760892
genetic diversity of campylobacter jejuni isolates from farm animals and the farm environment.the genetic diversity of campylobacter jejuni isolates from farm animals and their environment was investigated by multilocus sequence typing (mlst). a total of 30 genotypes, defined by allelic profiles (assigned to sequence types [sts]), were found in 112 c. jejuni isolates originating in poultry, cattle, sheep, starlings, and slurry. all but two of these genotypes belonged to one of nine c. jejuni clonal complexes previously identified in isolates from human disease and retail food samples and ...200314660392
survival of helicobacter pylori in a natural freshwater environment.the mode by which helicobacter pylori, the causative agent of most gastric ulcers, is transmitted remains undetermined. epidemiological evidence suggests these organisms are waterborne; however, h. pylori has rarely been grown from potential water sources. this may be due to the ability of this organism to rapidly enter the viable but nonculturable (vbnc) state. our investigation examines the entrance of h. pylori into this state in laboratory cultures and a natural freshwater environment as wel ...200314660399
simultaneous detection of mutations associated with resistance to macrolides and quinolones in campylobacter jejuni and c. coli using a pcr-line probe assay.quinolone and macrolide resistance of campylobacter jejuni and campylobacter coli mainly depend on a mutation in gyra and in 23s rdna, respectively. in order to detect quinolone and/or macrolide resistant c. jejuni and c. coli strains, a macrolide and quinolone line probe assay (mq-lipa) was developed and 42 c. jejuni and c. coli strains were tested to evaluate the efficiency of the assay. profiles of the mutations in 23s rdna and in gyra characterized by mq-lipa agreed with resistance to macrol ...200314522100
the iron-responsive regulator fur is transcriptionally autoregulated and not essential in neisseria meningitidis.fur is a well-known iron-responsive repressor of gene transcription, which is used by many bacteria to respond to the low-iron environment that pathogens encounter during infection. the fur gene in neisseria meningitidis has been described as an essential gene that may regulate a broad array of genes. we succeeded in obtaining an n. meningitidis mutant with the fur gene knocked out and used it to undertake studies of fur-mediated iron regulation. we show that expression of both fur and the trans ...200314526014
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
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
application of host-specific bacteriophages to the surface of chicken skin leads to a reduction in recovery of campylobacter jejuni.retail poultry products are widely purported as the major infection vehicle for human campylobacteriosis. numerous intervention strategies have sought to reduce campylobacter contamination on broiler carcasses in the abattoir. this study reports the efficacy of bacteriophage in reducing the number of recoverable campylobacter jejuni cells on artificially contaminated chicken skin.200314532096
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
comparison of campylobacter isolates from poultry and humans: association between in vitro virulence properties, biotypes, and pulsed-field gel electrophoresis clusters.the in vitro virulence properties of 197 temporally and geographically related campylobacter isolates from chicken broilers and humans were compared. comparisons of the virulence properties associated with genotypes and biotypes were made. all isolates adhered to, and 63% invaded, int-407 cells, whereas 13% were cytotoxic for cho cells. cho cell-cytotoxic extracts were also cytotoxic for int-407 cells, but the sensitivity for vero cells was variable. the proportion of isolates demonstrating a hi ...200314532099
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
deletion of helicobacter pylori vacuolating cytotoxin gene by introduction of directed mutagenesis.to construct a vaca-knockout helicobacter pylori mutant strain, whose only difference from the wild strain is its disrupted vaca gene.200314562387
investigation of infectious agents associated with arthritis by reverse transcription pcr of bacterial rrna.in reactive and postinfectious arthritis the joints are generally sterile but the presence of bacterial antigens and nucleic acids has been reported. to investigate whether organisms traffic to affected joints in these conditions, we performed reverse transcription pcr using universal primers to amplify any bacterial 16s rrna sequences present in synovial fluid. bacterial sequences were detected in most cases, even after treatment of the synovial fluid with dnase, implying the presence of bacter ...200312716447
detection and typing of campylobacter jejuni and campylobacter coli and analysis of indicator organisms in three waterborne outbreaks in finland.waterborne outbreaks associated with contamination of drinking water by campylobacter jejuni are rather common in the nordic countries sweden, norway, and finland, where in sparsely populated districts groundwater is commonly used without disinfection. campylobacters, escherichia coli, or other coliforms have rarely been detected in potential sources. we studied three waterborne outbreaks in finland caused by c. jejuni and used sample volumes of 4,000 to 20,000 ml for analysis of campylobacters ...200312620821
comparison of broth microdilution, e test, and agar dilution methods for antibiotic susceptibility testing of campylobacter jejuni and campylobacter coli.a standardized broth microdilution method was compared to the e test and an agar dilution method for the antimicrobial susceptibility testing of campylobacter jejuni and c. coli isolates. a group of 47 human clinical isolates, 37 isolates from retail poultry, and 29 isolates from living turkeys (total, 113 isolates) was included in the study. these encompassed 92 c. jejuni and 21 c. coli strains. the mics of six antimicrobial agents were determined by the broth microdilution and e test methods, ...200312624030
molecular typing of campylobacter jejuni and campylobacter coli. 200312624086
antimicrobial susceptibilities of campylobacter strains isolated from finnish subjects infected domestically or from those infected abroad.the in vitro susceptibilities of 678 campylobacter jejuni and campylobacter coli strains isolated from stool samples of the same number of finnish subjects were studied. a total of 523 patients, representing inhabitants from throughout finland, had not traveled abroad within the 2 weeks prior to becoming ill, whereas 155 persons had presumably acquired their infections abroad. the antimicrobial agents studied were erythromycin, ciprofloxacin, levofloxacin, trovafloxacin, and moxifloxacin. the mi ...200312499176
helicobacter pylori preferentially induces interleukin 12 (il-12) rather than il-6 or il-10 in human dendritic cells.dendritic cells are potent antigen-presenting cells that are present in the gastrointestinal tract and are required for the induction of a th1 t-cell acquired immune response. since infection with the gastric pathogen helicobacter pylori elicits a th1 cell response, the interaction of these organisms with dendritic cells should reflect the th1 bias. we incubated h. pylori with cultured human dendritic cells and measured the cytokine induction profile, comparing the response to that induced by sa ...200312819109
detection of conserved n-linked glycans and phase-variable lipooligosaccharides and capsules from campylobacter cells by mass spectrometry and high resolution magic angle spinning nmr spectroscopy.glycomics, the study of microbial polysaccharides and genes responsible for their formation, requires the continuous development of rapid and sensitive methods for the identification of glycan structures. in this study, methods for the direct analysis of sugars from 108 to 1010 cells are outlined using the human gastrointestinal pathogen, campylobacter jejuni. using capillary-electrophoresis coupled with sensitive electrospray mass spectrometry, we demonstrate variability in the lipid a componen ...200312716884
isolation of campylobacter jejuni and campylobacter coli from the gall bladder samples of sheep and identification by polymerase chain reaction.in this study, 100 gall bladder samples of sheep slaughtered at an abattoir in elaziğ province were examined for campylobacter jejuni and campylobacter coli by culture and polymerase chain reaction (pcr). preston campylobacter agar supplemented with 7% horse blood and preston selective supplement (oxoid, hampshire, uk) were used for isolation of the agents. campylobacter spp. were isolated in 66 samples, and they were identified as 34% c. jejuni and 32% c. coli. a multiplex pcr based upon the us ...200314629001
antimicrobial resistance in campylobacter jejuni and campylobacter coli strains isolated in 1991 and 2001-2002 from poultry and humans in berlin, germany.the susceptibilities of 430 campylobacter jejuni strains and 79 c. coli strains to six antimicrobial agents were tested and analyzed. the two sets of strains originated from retail market chicken and turkey samples and from humans, respectively, in berlin, germany. two groups of isolates, one dating from 1991 and the other dating from 2001-2002, were tested. of the campylobacter sp. isolates recovered from humans in 2001-2002, 45.1% were resistant to ciprofloxacin, 37.8% were resistant to tetrac ...200314638490
detection and enumeration of campylobacter jejuni and campylobacter coli by indirect impedimetry with an oxygen scavenging system.six strains of campylobacter jejuni and campylobacter coli were shown to grow in a variety of media, but, with one exception, they were unable to produce sufficient change in the electrical properties of the medium to allow their detection by impedance monitoring. with the use of an indirect method based on absorption of evolved carbon dioxide and a medium containing the oxygen scavenger oxyrase, all strains were detectable, and correlations between time to detection and the logarithm of the ino ...200314503735
comparison of the bax system with a multiplex pcr method for simultaneous detection and identification of campylobacter jejuni and campylobacter coli in environmental samples.the campylobacter detection is performed by conventional culture methods and the identification of campylobacter jejuni and campylobacter coli is principally based on the hippurate hydrolysis test. the two major drawbacks of this biochemical test for species identification include the inconsistency of the results and the presence of atypical strains, which can lead to the misidentification of an isolate. as an alternative, multiplex polymerase chain reaction (mpcr) protocols for the simultaneous ...200314527799
ribotyping characterisation of campylobacter isolates randomly collected from different sources in italy.in this study the potential for using the automated psti ribotyping as a primary library typing method to survey campylobacter and for identification of two thermophilic campylobacter jejuni and campylobacter coli species was evaluated. a total of 158 isolates randomly collected in italy from different sources were analyzed. a large percentage of chicken (28%), turkey (27%) and turkey meat (25%) isolates shared their ribotyping profiles (ribotypes) with those of humans, whereas the swine isolate ...200314522511
risk factors for sporadic campylobacter jejuni infections in rural michigan: a prospective case-control study.this case-control study investigated risk factors for campylobacteriosis in a rural population. exposure to live farm animals was hypothesized to increase the risk for campylobacter jejuni enteritis.200314652344
evaluation of the prospect microplate assay for detection of campylobacter: a routine laboratory perspective.to evaluate the use of the new enzyme-linked immunosorbent assay, the prospect campylobacter microplate assay (alexon-trend, minneapolis, mn, usa), which allows 2-h detection of both campylobacter jejuni and campylobacter coli antigen directly in stool specimens.200314616724
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
pseudaminic acid, the major modification on campylobacter flagellin, is synthesized via the cj1293 gene.flagellins from campylobacter jejuni 81-176 and campylobacter coli vc167 are heavily glycosylated. the major modifications on both flagellins are pseudaminic acid (pse5ac7ac), a nine carbon sugar that is similar to sialic acid, and an acetamidino-substituted analogue of pseudaminic acid (pseam). previous data have indicated that pseam is synthesized via pse5ac7ac in c. jejuni 81-176, but that the two sugars are synthesized using independent pathways in c. coli vc167. the cj1293 gene of c. jejuni ...200314617187
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
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
enhanced surveillance of campylobacter infection in the north west of england 1997-1999.to identify sources and routes of infection for sporadic cases of campylobacter infection in the north west of england.200312504607
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
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
effect of temperature on viability of campylobacter jejuni and campylobacter coli on raw chicken or pork skin.to determine growth and survival of campylobacter jejuni and campylobacter coli on chicken and pork, campylobacter spp. (10(4) cfu/cm2) were inoculated on pieces of raw, irradiated chicken or pork skin and exposed to temperatures ranging from -20 to 42 degrees c under either microaerobic or aerobic conditions. viable counts over 48 h declined 2 to 3 log cfu/cm2 at -20 degrees c and 1 to 2 log cfu/cm2 at 25 degrees c regardless of skin type, species of campylobacter, or level of oxygen. at 4 degr ...200314627278
birds, migration and emerging zoonoses: west nile virus, lyme disease, influenza a and enteropathogens.wild birds are important to public health because they carry emerging zoonotic pathogens, either as a reservoir host or by dispersing infected arthropod vectors. in addition, bird migration provides a mechanism for the establishment of new endemic foci of disease at great distances from where an infection was acquired. birds are central to the epidemiology of west nile virus (wnv) because they are the main amplifying host of the virus in nature. the initial spread of wnv in the u.s. along the ea ...200315931279
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
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
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
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
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
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
campylobacter, from obscurity to celebrity.after its successful isolation from stools in the 1970s, campylobacter jejuni has rapidly become the most commonly recognised cause of bacterial gastroenteritis in man. reported cases of human campylobacteriosis represent only a small fraction of the actual number. in industrialised countries, the incidence of c. jejuni/campylobacter coli infections peaks during infancy, and again in young adults aged 15-44 years. acute self-limited gastrointestinal illness, characterised by diarrhoea, fever and ...200415373879
a european survey of antimicrobial susceptibility among zoonotic and commensal bacteria isolated from food-producing animals.to study antimicrobial resistance in zoonotic bacteria isolated from food animals in different countries using uniform methodology.200415375107
nucleotide sequences and comparison of two large conjugative plasmids from different campylobacter species.two large tetracycline resistance (tcr) plasmids have been completely sequenced, the ptet plasmid (45.2 kb) from campylobacter jejuni strain 81-176 and a plasmid pcc31 (44.7 kb) from campylobacter coli strain cc31 that was isolated from a human case of severe gastroenteritis in the uk. both plasmids are mosaic in structure, having homologues of genes found in a variety of different commensal and pathogenic bacteria, but nevertheless, showed striking similarities in dna sequence and overall gene ...200415470128
[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
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
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
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
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
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
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
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
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
swimming and campylobacter infections.a matched case-control study was conducted to study risk factors for domestically acquired sporadic campylobacter infections in finland. swimming in natural sources of water was a novel risk factor. eating undercooked meat and drinking dug-well water were also independent risk factors for campylobacter infection.200415496253
antimicrobial resistance of campylobacter jejuni and campylobacter coli isolates in japan. 200415499812
frequency and spatial distribution of environmental campylobacter spp.humans are exposed to campylobacter spp. in a range of sources via both food and environmental pathways. for this study, we explored the frequency and distribution of thermophilic campylobacter spp. in a 10- by 10-km square rural area of cheshire, united kingdom. the area contains approximately 70, mainly dairy, farms and is used extensively for outdoor recreational activities. campylobacter spp. were isolated from a range of environmental samples by use of a systematic sampling grid. livestock ...200415528512
detection of campylobacter spp. in chicken fecal samples by real-time pcr.a real-time pcr assay for detecting thermophilic campylobacter spp. directly in chicken feces has been developed. dna was isolated from fecal material by using magnetic beads followed by pcr with a prealiquoted pcr mixture, which had been stored at -18 degrees c. campylobacter could be detected in less than 4 h, with a detection limit of 100 to 150 cfu/ml, in a fecal suspension. a bacterial internal control was added before dna extraction to control both dna isolation and the presence of pcr inh ...200415528705
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
insufficient production and tissue delivery of cd4+ memory t cells in rapidly progressive simian immunodeficiency virus infection.the mechanisms linking human immunodeficiency virus replication to the progressive immunodeficiency of acquired immune deficiency syndrome are controversial, particularly the relative contribution of cd4+ t cell destruction. here, we used the simian immunodeficiency virus (siv) model to investigate the relationship between systemic cd4+ t cell dynamics and rapid disease progression. of 18 rhesus macaques (rms) infected with ccr5-tropic sivmac239 (n=14) or cxcr4-tropic sivmac155t3 (n=4), 4 of the ...200415545355
campylobacter insulaenigrae sp. nov., isolated from marine mammals.phenotypic and phylogenetic studies were performed on four campylobacter-like organisms recovered from three seals and a porpoise. comparative 16s rrna gene sequencing studies demonstrated that the organisms represent a hitherto unknown subline within the genus campylobacter, associated with a subcluster containing campylobacter jejuni, campylobacter coli and campylobacter lari. dna-dna hybridization studies confirmed that the bacteria belonged to a single species, for which the name campylobact ...200415545485
global transposon mutagenesis and essential gene analysis of helicobacter pylori.we have constructed a genome-saturating mutant library of the human gastric pathogen helicobacter pylori. microarray tracking of transposon mutants (matt) allowed us to map the position of 5,363 transposon mutants in our library. while we generally found insertions well distributed throughout the genome, 344 genes had no detectable transposon insertions, and this list is predicted to be highly enriched for essential genes. comparison to the essential gene set of other bacteria revealed a surpris ...200415547264
pcr-restriction fragment length polymorphism assay for detection of gyra mutations associated with fluoroquinolone resistance in campylobacter coli.a fragment of the gyra gene was sequenced from 34 isolates of campylobacter coli, including 23 isolates resistant to ciprofloxacin. all ciprofloxacin-resistant isolates examined by dna sequencing carried a point mutation at position thr-86 on the gyra gene product, involving the replacement of thr-86 by ile. a combined pcr-restriction fragment length polymorphism technique using rsai was developed to detect this mutation.200415561873
regional risks and seasonality in travel-associated campylobacteriosis.the epidemiology of travel-associated campylobacteriosis is still largely unclear, and various known risk factors could only explain limited proportions of the recorded cases.200415569393
diagnostic real-time pcr for detection of salmonella in food.a robust 5' nuclease (taqman) real-time pcr was developed and validated in-house for the specific detection of salmonella in food. the assay used specifically designed primers and a probe target within the ttrrsbca locus, which is located near the salmonella pathogenicity island 2 at centisome 30.5. it is required for tetrathionate respiration in salmonella. the assay correctly identified all 110 salmonella strains and 87 non-salmonella strains tested. an internal amplification control, which is ...200415574899
characterization of lactobacillus coryniformis dsm 20001t surface protein cpf mediating coaggregation with and aggregation among pathogens.phenotypic characterization of aggregation phenotypes of lactobacillus coryniformis revealed that strain dsm 20001t coaggregated with escherichia coli k88, campylobacter coli, and campylobacter jejuni but not with other human pathogens. in addition, cells of these pathogens aggregated in the presence of the spent culture supernatant (scs) of strain dsm 20001t. cells of e. coli k88 remained viable in the coaggregates and aggregates for up to 24 h. both coaggregation and aggregation (co/aggregatio ...200415574903
survival of cold-stressed campylobacter jejuni on ground chicken and chicken skin during frozen storage.campylobacter jejuni is prevalent in poultry, but the effect of combined refrigerated and frozen storage on its survival, conditions relevant to poultry processing and storage, has not been evaluated. therefore, the effects of refrigeration at 4 degrees c, freezing at -20 degrees c, and a combination of refrigeration and freezing on the survival of c. jejuni in ground chicken and on chicken skin were examined. samples were enumerated using tryptic soy agar containing sheep's blood and modified c ...200415574906
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
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 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
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
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
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
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
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
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
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
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
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