Publications

TitleAbstractYear(sorted descending)
Filter
PMID
Filter
novel clonal complexes with an unknown animal reservoir dominate campylobacter jejuni isolates from river water in new zealand.campylobacter jejuni is widely distributed in the environment, and river water has been shown to carry high levels of the organism. in this study, 244 c. jejuni isolates from three river catchment areas in new zealand were characterized using multilocus sequence typing. forty-nine of the 88 sequence types identified were new. the most common sequence types identified were st-2381 (30 isolates), st-45 (25 isolates), and st-1225 (23 isolates). the majority of the sequence types identified in the r ...200919648367
temporal patterns and risk factors for escherichia coli o157 and campylobacter spp, in young cattle.escherichia coli o157 and campylobacter jejuni and campylobacter coli are zoonotic pathogens originating from farm animals. cattle are the main reservoir for e. coli o157 and also contribute to human cases of campylobacteriosis through contaminated milk, direct contact, and environmental contamination. thirty groups of young cattle on 30 farms were observed for 7 months and sampled on 4 to 6 separate occasions for e. coli o157 and c. jejuni/coli to characterize shedding patterns and identify ris ...200919343935
mouse intestine colonization ability of campylobacter coli strains.campylobacter coli is an etiological agent of gastrointestinal and extraintestinal infections in man and animals, and can be found as a commensal in gastrointestinal tract of animals. in this study, we aimed to determine differences among c coli strains in colonization of the intestinal tract of mice. seven c coli strains isolated from diarrheic patients, asymptomatic hosts and chicken carcasses were used for this study. each strain was inoculated with 0.1 ml of a bacterial suspension (3 x 10(8) ...200919753795
amoxicillin therapy of poultry flocks: effect upon the selection of amoxicillin-resistant commensal campylobacter spp.the aim of this study was to investigate the effect of amoxicillin therapy of poultry flocks upon the persistence of commensal campylobacter spp. and the incidence of antibiotic resistance.200919656785
comparative studies of campylobacter jejuni genomic diversity reveal the importance of core and dispensable genes in the biology of this enigmatic food-borne pathogen.mlst, dna microarrays, and genome sequencing has allowed for a greater understanding of the metabolic capacity and epidemiology of campylobacter jejuni. while strain-specific genes may provide an isolate a selective advantage in environments and contribute to the organism's pathogenicity, recent work indicates that c. jejuni pathogenicity is dictated by variations in the nucleotide sequence of core genes. challenges facing c. jejuni researchers include determining (a) the degree to which genomic ...200919346123
[evaluation of genotypic and phenotypic methods for the differentiation of campylobacter jejuni and campylobacter coli clinical isolates from poland. i. biotyping, resistance pattern, plasmid analysis, restriction enzyme analysis of plasmid].a total of 128 clinical isolates of c. jejuni and 17 clinical isolates of c. coli were characterized by their plasmid profiles, susceptibility to six antimicrobial agents and the lior biotypes. we also analyzed seven isolates from three c. jejuni family outbreaks and three isolates from one c. coli family outbreak. plasmids were found in 47 c. jejuni (36.7%) and 3 c. coli (17.6%) isolates. the sizes of plasmids detected ranged from about 3.3 to 89 kb. the majority of campylobacter isolates (n = ...200919517815
[determination of sensitivity to antibiotics of campylobacter jejuni and campylobacter coli isolated from human feces].one of the most important bacterial zoonosis is campylobacteriosis. human disease is mostly caused by thermophilic campylobacter spp: campylobacter jejuni (c. jejuni), campylobacter coli (c. coli), campylobacter lari (c. lari) and campylobacter upsakensis (campsalensis). campylobacteriosis is a mild and self-healing disorder. in patients with more severe and prolonged forms, an antibiotic treatment is recommended. recommended drugsare erythromycin, ciprofloxacin, tetracyclin, chloramphenicol and ...200919195264
[evaluation of genotypic and phenotypic methods for the differentiation of campylobacter jejuni and campylobacter coli clinical isolates from poland. ii. pfge, eric-pcr, pcr-flaa-rflp and mlst].campylobacter jejuni and campylobacter coli are leading cause of bacterial gastroenteritis in many developed countries. we compared pulsed-field gel electrophoresis (pfge), enterobacterial repetitive intergenic consensus (eric-pcr) and restriction fragment length polymorphisms of the flagellin gene (pcr-flaa-rflp) for distinguishing 128 c. jejuni isolates and 17 c. coli clinical isolates isolated between 2006 and 2007 in poland. we also analysed seven isolates from three c. jejuni family outbrea ...200919517816
pyrazolopyrimidinediones are selective agents for helicobacter pylori that suppress growth through inhibition of glutamate racemase (muri).pyrazolopyrimidinediones are a novel series of compounds that inhibit growth of helicobacter pylori specifically. using a variety of methods, advanced analogues were shown to suppress the growth of h. pylori through the inhibition of glutamate racemase, an essential enzyme in peptidoglycan biosynthesis. the high degree of selectivity of the series for h. pylori makes these compounds attractive candidates for novel h. pylori-selective therapy.200919433553
campylobacter coli naturally resistant to elevated levels of gentamicin as a marker strain in poultry research.campylobacter inoculation studies are limited without a suitable marker strain. the lurpose of this study was to screen campylobacter strains (n=2073) obtained from poultry carcass rinses through the centers for disease control and prevention's national antimicrobial resistant monitoring system for resistance to gentamicin and evaluate one strain's efficacy as a marker. a c. coli strain was found resistant to gentamicin at >32 microg/ml. gentamicin was incorporated into media (campy-cefex agar, ...200919610342
campylobacter jejuni glycosylation island important in cell charge, legionaminic acid biosynthesis, and colonization of chickens.previously, we identified five genes (cj1321 to cj1326, of which cj1325 and cj1326 are a single gene) in the o-linked flagellin glycosylation island that are highly prevalent in campylobacter jejuni isolates from chickens. we report mutagenesis, functional, and structural data to confirm that this locus, and cj1324 in particular, has a significant contributory role in the colonization of chickens by c. jejuni. a motile deltacj1324 mutant with intact flagella was considerably less hydrophobic and ...200919307210
detection of escherichia coli, salmonella spp., shigella spp., yersinia enterocolitica, vibrio cholerae, and campylobacter spp. enteropathogens by 3-reaction multiplex polymerase chain reaction.the magnitude of bacterial diarrhea in developing countries is largely unknown because affordable detection methods are not available. we have developed a polymerase chain reaction (pcr)-based assay for use in areas with limited resources to screen for diarrheogenic strains from clinical isolates. to simplify the assay and minimize reagents, our method implemented the use of plasmids rather than bacteria as template controls and the use of bacterial suspensions or crude dna preparations rather t ...200918990527
detection of escherichia coli, salmonella spp., shigella spp., yersinia enterocolitica, vibrio cholerae, and campylobacter spp. enteropathogens by 3-reaction multiplex polymerase chain reaction.the magnitude of bacterial diarrhea in developing countries is largely unknown because affordable detection methods are not available. we have developed a polymerase chain reaction (pcr)-based assay for use in areas with limited resources to screen for diarrheogenic strains from clinical isolates. to simplify the assay and minimize reagents, our method implemented the use of plasmids rather than bacteria as template controls and the use of bacterial suspensions or crude dna preparations rather t ...200918990527
erythromycin resistance by l4/l22 mutations and resistance masking by drug efflux pump deficiency.we characterized the effects of classical erythromycin resistance mutations in ribosomal proteins l4 and l22 of the large ribosomal subunit on the kinetics of erythromycin binding. our data are consistent with a mechanism in which the macrolide erythromycin enters and exits the ribosome through the nascent peptide exit tunnel, and suggest that these mutations both impair passive transport through the tunnel and distort the erythromycin-binding site. the growth-inhibitory action of erythromycin w ...200919197244
antiganglioside antibodies and their pathophysiological effects on guillain-barré syndrome and related disorders--a review.guillain-barré syndrome (gbs) is an acute immune-mediated polyradiculoneuropathy which can cause acute quadriplegia. infection with micro-organisms, including campylobacter jejuni (c. jejuni), haemophilus influenzae, and cytomegalovirus (cmv), is recognized as a main triggering event for the disease. lipooligosaccharide (los) genes are responsible for the formation of human ganglioside-like los structures in infectious micro-organisms that can induce gbs. molecular mimicry of loss on the surface ...200919240270
antibiotic resistance in campylobacter: emergence, transmission and persistence.campylobacter is a leading foodborne bacterial pathogen, which causes gastroenteritis in humans. this pathogenic organism is increasingly resistant to antibiotics, especially fluoroquinolones and macrolides, which are the most frequently used antimicrobials for the treatment of campylobacteriosis when clinical therapy is warranted. as a zoonotic pathogen, campylobacter has a broad animal reservoir and infects humans via contaminated food, water or milk. antibiotic usage in both animal agricultur ...200919257846
attribution of campylobacter infections in northeast scotland to specific sources by use of multilocus sequence typing.we show that a higher incidence of campylobacteriosis is found in young children (age, <5 years) living in rural, compared with urban, areas. association of this difference with particular animal sources was evaluated using multilocus sequence typing. this evaluation was achieved by comparing campylobacter isolates originating from these children, retail poultry, and a range of animal sources by use of source attribution and phylogenetic analysis methods. the results indicate that chicken is a m ...200919265482
campylobacter genotyping to determine the source of human infection.campylobacter species cause a high proportion of bacterial gastroenteritis cases and are a significant burden on health care systems and economies worldwide; however, the relative contributions of the various possible sources of infection in humans are unclear.200919275496
the cmp-legionaminic acid pathway in campylobacter: biosynthesis involving novel gdp-linked precursors.the sialic acid-like sugar 5,7-diacetamido-3,5,7,9-tetradeoxy-d-glycero-d-galacto-nonulosonic acid, or legion-aminic acid, is found as a virulence-associated cell-surface glycoconjugate in the gram-negative bacteria legionella pneumophila and campylobacter coli. l. pneumophila serogroup 1 strains, causative agents of legionnaire's disease, contain an alpha2,4-linked homopolymer of legionaminic acid within their lipopolysaccharide o-chains, whereas the gastrointestinal pathogen c. coli modifies i ...200919282391
evaluation of procedures for outer membrane isolation from campylobacter jejuni.although infection with campylobacter jejuni is one of the leading causes of gastroenteritis worldwide, relatively little is known about the factors that are required to elicit a protective immune response. the need for a vaccine against this pathogen is well recognized and a number of vaccine candidates have been tested with varying degrees of success; however, there is still a lack of a suitable vaccine. to gain a better understanding of the outer-membrane protein components of this organism, ...200919246768
molecular epidemiology and characterization of campylobacter spp. isolated from wild bird populations in northern england.campylobacter infections have been reported at prevalences ranging from 2 to 50% in a range of wild bird species, although there have been few studies that have investigated the molecular epidemiology of campylobacter spp. consequently, whether wild birds are a source of infection in humans or domestic livestock or are mainly recipients of domestic animal strains and whether separate cycles of infection occur remain unknown. to address these questions, serial cross-sectional surveys of wild bird ...200919286781
incidence and risk factors for community-acquired acute gastroenteritis in north-west germany in 2004.in developed countries, acute gastroenteritis (age) is a major source of morbidity. however, only a few studies have estimated its incidence and the associated medical burden. this population-based study determined the incidence of community-acquired age patients seeking medical care and the relative role of various pathogens. stool samples from patients with age presenting to a general practitioner (gp), pediatrician, or specialist in internal medicine for that reason were screened for various ...200919319582
survival at refrigeration and freezing temperatures of campylobacter coli and campylobacter jejuni on chicken skin applied as axenic and mixed inoculums.campylobacter is considered to be the most common cause of bacterial diarrhoeal illness in the developed world. many cases are thought to be acquired from consumption of undercooked poultry. the aim of this study was to compare the effect of the rate of cooling on the survival, at 4 degrees c and -20 degrees c, of campylobacter coli and campylobacter jejuni strains, inoculated on chicken skin from axenic culture or as mixed inoculums. strains chilled in a domestic refrigerator varied in their to ...200919324444
comparison of loop-mediated isothermal amplification assay and conventional culture methods for detection of campylobacter jejuni and campylobacter coli in naturally contaminated chicken meat samples.we investigated the efficacy of a loop-mediated isothermal amplification (lamp) assay for detection of chicken meat samples naturally contaminated with campylobacter jejuni and campylobacter coli. a total of 144 preston enrichment broth cultures from chicken meat samples were assessed by using the lamp assay and conventional culture methods, which consist of a combination of preston enrichment culturing and plating onto butzler and modified charcoal cefoperazone deoxycholate agars. compared with ...200919139242
occurrence and enumeration of campylobacter spp. during the processing of chilean broilers.thermotolerant campylobacter is among the more prevalent bacterial pathogens that cause foodborne diseases. this study aimed at evaluating the occurrence of thermotolerant campylobacter contamination in chicken carcasses and processing plant stations (chilling water, scalding water, defeathering machinery, evisceration machine, and transport crates) in two of the chilean main slaughterhouses. in addition, the isolation rates of thermotolerant campylobacter during evisceration and following chill ...200919445680
survival rate of thermotolerant campylobacter on poultry meat during microwave heating.survival rates of campylobacterjejuni atcc 33 291, campylobacter jejuni pzh 38 and campylobacter coli atcc 43 478 in leg quarters (ca 330 g) of chicken broilers after microwave heating (480 and 760 watt) for 2, 4, 6, 8 and 10 minutes were determined. heating the meat in a microwave oven (moulinex, type dialog cook) at 480 watts caused a gradual decrease in the number of cells of the studied bacterial strains to total inactivation after 8-10 minutes of heating. increasing the heating power to 760 ...200919459438
identification of novel carbohydrate modifications on campylobacter jejuni 11168 flagellin using metabolomics-based approaches.it is well known that the flagellin of campylobacter jejuni is extensively glycosylated by pseudaminic acid and the related acetamindino derivative, in addition to flagellin glycosylation being essential for motility and colonization of host cells. recently, the use of metabolomics permitted the unequivocal characterization of unique flagellin modifications in campylobacter, including novel legionaminic acid sugars in campylobacter coli, which had been impossible to ascertain in earlier studies ...200919154343
campylobacter colonization of the turkey intestine in the context of microbial community development.patterns of microbial community dynamics in the turkey intestine were examined. every week of the 18-week production cycle, cecal bacterial communities and campylobacter loads were examined from five birds for each of two flocks. molecular fingerprinting via the automated ribosomal intergenic spacer analysis (arisa) and terminal restriction fragment length polymorphism (t-rflp) of the cecal samples revealed that microbial communities changed in a time-dependent manner, and during both trials the ...200919346343
campylobacter genotypes from food animals, environmental sources and clinical disease in scotland 2005/6.a nationwide multi-locus sequence typing (mlst) survey was implemented to analyze patterns of host association among campylobacter jejuni and campylobacter coli isolates from clinical disease in scotland (july 2005-september 2006), food animals (chickens, cattle, sheep, pigs and turkey), non-food animals (wild birds) and the environment. sequence types (sts) were determined for 5247 clinical isolates and 999 from potential disease sources (augmented with 2420 published sts). certain sts were ove ...200919269051
inter- and intra-genomic heterogeneity of the intervening sequence in the 23s ribosomal rna gene of campylobacter jejuni and campylobacter coli.an intervening sequence (ivs) can be present or absent in the 23s rrna of campylobacter jejuni and campylobacter coli. as part of a survey, we used a polymerase chain reaction (pcr) assay to detect the presence of the ivs in 43 isolates of c. coli and 82 isolates of c. jejuni. an ivs was present in 40 (93.0%) of the c. coli and only 34 (41.5%) of the c. jejuni isolates. twelve (27.9%) of the c. coli isolates and seven (8.5%) of the c. jejuni isolates resulted in two polymerase chain reaction pro ...200919201124
production and characterization of a monoclonal antibody to campylobacter jejuni.campylobacter species are a group of spiral-shaped bacteria that can cause disease in humans and animals. we developed a high-affinity monoclonal antibody (mab) probe that recognizes campylobacter jejuni cells. cell suspensions grown under microaerobic conditions at 42 degrees c for 20 h on bolton agar plates with lysed horse blood were used as live and heat-killed preparations, centrifuged at 8,000 x g for 20 min, and resuspended in carbonate buffer (ph 9.6) for coating on the enzyme-linked imm ...200919435241
application of a group ii campylobacter bacteriophage to reduce strains of campylobacter jejuni and campylobacter coli colonizing broiler chickens.members of the genus campylobacter are frequently responsible for human enteric disease worldwide. persistent campylobacter contamination of poultry meat is a common problem that represents a significant food safety risk through the consumption of undercooked poultry meat or through cross-contamination of other foods during the preparation of poultry. bacteriophage therapy is one possible means by which this colonization of poultry could be controlled, thus limiting the entry of campylobacter in ...200919435220
a single nucleotide change affects fur-dependent regulation of sodb in h. pylori.helicobacter pylori is a significant human pathogen that has adapted to survive the many stresses found within the gastric environment. superoxide dismutase (sodb) is an important factor that helps h. pylori combat oxidative stress. sodb was previously shown to be repressed by the ferric uptake regulator (fur) in the absence of iron (apo-fur regulation) [1]. herein, we show that apo regulation is not fully conserved among all strains of h. pylori. apo-fur dependent changes in sodb expression are ...200919399190
prevalence of campylobacter jejuni and campylobacter coli in market-weight turkeys on-farm and at slaughter.to monitor the effects of feed withdrawal on the prevalence of campylobacter, market-weight turkeys from six farms were examined before and after perimarketing events (feed withdrawal, transport, and holding at the slaughterhouse). prior to transport, birds (n = 30 per farm) were slaughtered on-farm, and viscera (crops, duodenum, jejunum, ileum, colon, ceca, gallbladder, and spleen) were removed on the premises. within ca. 48 h, cohorts (n = 30 per farm) from the same flock were transported to a ...200919205462
campylobacter jejuni in penguins, antarctica. 200919402996
transmission of foodborne zoonotic pathogens to riparian areas by grazing sheep.the objective of this study was to determine if sheep grazing near riparian areas on pasture in ontario are an important risk factor for the contamination of water with specific foodborne pathogens. ten ontario sheep farms were visited weekly for 12 wk during the summer of 2005. samples of feces, soil, and water were collected and analyzed for the presence of escherichia coli o157:h7, salmonella spp., campylobacter jejuni and c. coli, and yersinia enterocolitica, by bacteriological identificatio ...200919436581
regulation of superoxide dismutase (sod) genes by sara in staphylococcus aureus.the scavenging of reactive oxygen species (ros) within cells is regulated by several interacting factors, including transcriptional regulators. involvement of sara family genes in the regulation of proteins involved in the scavenging of ros is largely unknown. in this report, we show that under aerobic conditions, the levels of sodm and soda transcription, in particular the sodm transcript, are markedly enhanced in the sara mutant among the tested sara family mutants. increased levels of sod exp ...200919286803
the helicobacter pylori anti-sigma factor flgm is predominantly cytoplasmic and cooperates with the flagellar basal body protein flha.helicobacter pylori requires flagellar motility and orientation to persist actively in its habitat. a particular feature of flagella in most helicobacter species including h. pylori is a membraneous flagellar sheath. the anti-sigma factor flgm of h. pylori is unusual, since it lacks an n-terminal domain present in other flgm homologs, e.g., flgm of salmonella spp., whose regulatory function is intimately coupled to its secretion through the flagellar type iii secretion system. the aim of the pre ...200919465658
beta-lactamase-mediated beta-lactam resistance in campylobacter species: prevalence of cj0299 (bla oxa-61) and evidence for a novel beta-lactamase in c. jejuni.fifty-two percent of 1,288 poultry isolates of campylobacters were ampicillin resistant, and resistance was more common among campylobacter coli isolates (67.4%) than among campylobacter jejuni isolates (47.5%). production of beta-lactamase was typically associated with resistance to ampicillin, amoxicillin (amoxicilline), penicillin, and ticarcillin. regardless of beta-lactamase production, all isolates were resistant to piperacillin (mics >or= 256 microg/ml), and most were resistant to carbeni ...200919506058
a longitudinal study of campylobacter distribution in a turkey production chain.campylobacter is the most common cause of bacterial enteritis worldwide. handling and eating of contaminated poultry meat has considered as one of the risk factors for human campylobacteriosis. campylobacter contamination can occur at all stages of a poultry production cycle. the objective of this study was to determine the occurrence of campylobacter during a complete turkey production cycle which lasts for 1,5 years of time. for detection of campylobacter, a conventional culture method was com ...200919348687
the dual-functioning fumarate reductase is the sole succinate:quinone reductase in campylobacter jejuni and is required for full host colonization.campylobacter jejuni encodes all the enzymes necessary for a complete oxidative tricarboxylic acid (tca) cycle. because of its inability to utilize glucose, c. jejuni relies exclusively on amino acids as the source of reduced carbon, and they are incorporated into central carbon metabolism. the oxidation of succinate to fumarate is a key step in the oxidative tca cycle. c. jejuni encodes enzymes annotated as a fumarate reductase (cj0408 to cj0410) and a succinate dehydrogenase (cj0437 to cj0439) ...200919525346
prevalence of thermotolerant campylobacter in partridges (perdix perdix).to estimate the prevalence of thermotolerant campylobacter spp. in commercially reared partridges (perdix perdix) in southern italy.200919552770
population structure of streptococcus oralis.streptococcus oralis is a member of the normal human oral microbiota, capable of opportunistic pathogenicity; like related oral streptococci, it exhibits appreciable phenotypic and genetic variation. a multilocus sequence typing (mlst) scheme for s. oralis was developed and the resultant data analysed to examine the population structure of the species. analysis of 113 isolates, confirmed as belonging to the s. oralis/mitis group by 16s rrna gene sequencing, characterized the population as highly ...200919423627
campylobacter immunity and coinfection following a large outbreak in a farming community.an outbreak of campylobacteriosis affected approximately one-half of 165 people attending an annual farmers' dance in montrose, scotland, in november 2005. epidemiological investigations, including a cohort study (n = 164), identified chicken liver paté as the most likely vehicle of infection. paté preparation involved deliberate undercooking of chicken livers by flash-frying, followed by mechanical homogenization. typing of 32 campylobacter strains (isolated from submitted stools) by multilocus ...200919005146
genotyping of campylobacter coli isolated from humans and retail meats using multilocus sequence typing and pulsed-field gel electrophoresis.to determine the antimicrobial resistant profiles and clonality of campylobacter coli isolated from clinically ill humans and retail meats.200919226383
a pan-european survey of antimicrobial susceptibility towards human-use antimicrobial drugs among zoonotic and commensal enteric bacteria isolated from healthy food-producing animals.the aim of the study was to study antimicrobial susceptibility in escherichia coli, salmonella, campylobacter and enterococcus recovered from chickens, pigs and cattle using uniform methodology.200919233897
campylobacter immunity and coinfection following a large outbreak in a farming community.an outbreak of campylobacteriosis affected approximately one-half of 165 people attending an annual farmers' dance in montrose, scotland, in november 2005. epidemiological investigations, including a cohort study (n = 164), identified chicken liver paté as the most likely vehicle of infection. paté preparation involved deliberate undercooking of chicken livers by flash-frying, followed by mechanical homogenization. typing of 32 campylobacter strains (isolated from submitted stools) by multilocus ...200919005146
campylobacter and arcobacter species sensitivity to commercial orange oil fractions.seven orange oil fractions were screened for their ability to inhibit the growth of selected campylobacter and arcobacter spp. using the standard agar-disk diffusion assay. cold pressed (cp) terpeneless valencia orange oil was found to be the most inhibitory to both campylobacter jejuni and campylobacter coli, exhibiting maximum zones of inhibition up to 80+/-0.0 mm. five-fold concentrated valencia oil and distilled d-limonene resulted in campylobacter inhibition zones ranging from 11.0+/-1.4 to ...200919070381
antimicrobial activity of prulifloxacin tested against a worldwide collection of gastroenteritis-producing pathogens, including those causing traveler's diarrhea.prulifloxacin, the prodrug of ulifloxacin (active component), is a newer fluoroquinolone with broad activity against enteric and nonenteric gram-negative bacilli. ulifloxacin and other oral comparator agents were tested for activity against 582 gastroenteritis strains from global surveillance studies. ulifloxacin was highly active against escherichia coli, salmonella spp., shigella spp., yersinia spp., vibrio spp., aeromonas spp., and plesiomonas spp. (mic(50)s and mic(90)s, <or=0.03 microg/ml a ...200919114678
antimicrobial activity of prulifloxacin tested against a worldwide collection of gastroenteritis-producing pathogens, including those causing traveler's diarrhea.prulifloxacin, the prodrug of ulifloxacin (active component), is a newer fluoroquinolone with broad activity against enteric and nonenteric gram-negative bacilli. ulifloxacin and other oral comparator agents were tested for activity against 582 gastroenteritis strains from global surveillance studies. ulifloxacin was highly active against escherichia coli, salmonella spp., shigella spp., yersinia spp., vibrio spp., aeromonas spp., and plesiomonas spp. (mic(50)s and mic(90)s, <or=0.03 microg/ml a ...200919114678
diversity and habitat specificity of free-living protozoa in commercial poultry houses.despite stringent biosecurity measures, infections by bacterial food pathogens such as campylobacter are a recurrent problem in industrial poultry houses. as the main transmission route remains unclear, persistence of these infections has been linked to bacterial survival and possibly multiplication within protozoan vectors. to date, however, virtually no information is available on the diversity and occurrence of free-living protozoa in these environments. using a combination of microscopic ana ...200919124593
independent evolution of neurotoxin and flagellar genetic loci in proteolytic clostridium botulinum.proteolytic clostridium botulinum is the causative agent of botulism, a severe neuroparalytic illness. given the severity of botulism, surprisingly little is known of the population structure, biology, phylogeny or evolution of c. botulinum. the recent determination of the genome sequence of c. botulinum has allowed comparative genomic indexing using a dna microarray.200919298644
structures of acrr and cmer: insight into the mechanisms of transcriptional repression and multi-drug recognition in the tetr family of regulators.the transcriptional regulators of the tetr family act as chemical sensors to monitor the cellular environment in many bacterial species. to perform this function, members of the tetr family harbor a diverse ligand-binding domain capable of recognizing the same series of compounds as the transporters they regulate. many of the regulators can be induced by a wide array of structurally unrelated compounds. binding of these structurally unrelated ligands to the regulator results in a conformational ...200919130905
structures of acrr and cmer: insight into the mechanisms of transcriptional repression and multi-drug recognition in the tetr family of regulators.the transcriptional regulators of the tetr family act as chemical sensors to monitor the cellular environment in many bacterial species. to perform this function, members of the tetr family harbor a diverse ligand-binding domain capable of recognizing the same series of compounds as the transporters they regulate. many of the regulators can be induced by a wide array of structurally unrelated compounds. binding of these structurally unrelated ligands to the regulator results in a conformational ...200919130905
recombineering reveals a diverse collection of ribosomal proteins l4 and l22 that confer resistance to macrolide antibiotics.mutations in ribosomal proteins l4 and l22 confer resistance to erythromycin and other macrolide antibiotics in a variety of bacteria. l4 and l22 have elongated loops whose tips converge in the peptide exit tunnel near the macrolide-binding site, and resistance mutations typically affect residues within these loops. here, we used bacteriophage lambda red-mediated recombination, or "recombineering," to uncover new l4 and l22 alleles that confer macrolide resistance in escherichia coli. we randomi ...200919150357
a dnase encoded by integrated element cjie1 inhibits natural transformation of campylobacter jejuni.the species campylobacter jejuni is considered naturally competent for dna uptake and displays strong genetic diversity. nevertheless, nonnaturally transformable strains and several relatively stable clonal lineages exist. in the present study, the molecular mechanism responsible for the nonnatural transformability of a subset of c. jejuni strains was investigated. comparative genome hybridization indicated that c. jejuni mu-like prophage integrated element 1 (cjie1) was more abundant in nonnatu ...200919151136
severe diarrhoea caused by highly ciprofloxacin-susceptible campylobacter isolates.the impact of fluoroquinolone resistance of campylobacter jejuni and campylobacter coli isolates on the outcome of the disease in sporadic campylobacter infections of finnish individuals was studied. questionnaires were sent, during a 6-month study period, to patients who were stool culture-positive for campylobacter spp. in total, 192 returned questionnaires were analysed and assessed, together with the susceptibility data of the respective bacterial isolates. only one (2%) of the domestic, but ...200919154485
initial studies using aliphatic beta-nitro alcohols for therapeutic corneal cross-linking.corneal collagen cross-linking through uva-riboflavin photochemistry (uvar) has been shown to be an effective treatment for keratoconus and related keratectasias. in recent studies using sclera, the authors observed that short-chain aliphatic beta-nitro alcohols can cross-link collagenous tissue under physiologic conditions. thus, this study was undertaken to evaluate these agents as potential pharmacologic alternatives to uvar.200918836172
initial studies using aliphatic beta-nitro alcohols for therapeutic corneal cross-linking.corneal collagen cross-linking through uva-riboflavin photochemistry (uvar) has been shown to be an effective treatment for keratoconus and related keratectasias. in recent studies using sclera, the authors observed that short-chain aliphatic beta-nitro alcohols can cross-link collagenous tissue under physiologic conditions. thus, this study was undertaken to evaluate these agents as potential pharmacologic alternatives to uvar.200918836172
rapid evolution and the importance of recombination to the gastroenteric pathogen campylobacter jejuni.responsible for the majority of bacterial gastroenteritis in the developed world, campylobacter jejuni is a pervasive pathogen of humans and animals, but its evolution is obscure. in this paper, we exploit contemporary genetic diversity and empirical evidence to piece together the evolutionary history of c. jejuni and quantify its evolutionary potential. our combined population genetics-phylogenetics approach reveals a surprising picture. campylobacter jejuni is a rapidly evolving species, subje ...200919008526
can campylobacter coli induce guillain-barré syndrome? 200919002726
prevalence of campylobacter jejuni and its resistance to antibiotics in poultry in the czech republic.thermotolerant campylobacter spp., in particular campylobacter jejuni, are among the most frequently identified pathogens, found to be causing human gastrointestinal infections in europe, with the czech republic being no exception. the presented work aimed at assessing results of the first nationwide monitoring of prevalence and antibiotic resistance of campylobacter spp. in broiler flocks in the czech republic, including a comparison of antibiotic resistance of c. jejuni isolates collected from ...200918771516
23s rrna gene mutations contributing to macrolide resistance in campylobacter jejuni and campylobacter coli.the genetic basis of macrolide resistance in campylobacter coli (n = 17) and c. jejuni (n = 35) isolates previously subjected to in vivo selective pressure was investigated to determine if the number of copies of 23s rrna genes with macrolide-associated mutations affects the minimum inhibitory concentration (mic) of macrolides. sequence data for domain v of the 23s rrna gene revealed that two macrolide-resistant c. coli isolates had adenine-->guanine transitions at position 2059 (a2059g, escheri ...200919014274
survival of campylobacter spp. in bovine faeces on pasture.to determine the survival on pasture of campylobacter spp. naturally present in bovine faeces and compare this with a previously published study using laboratory-cultured campylobacter spp.200919018956
a campylobacter jejuni znua orthologue is essential for growth in low-zinc environments and chick colonization.campylobacter jejuni infection is a leading cause of bacterial gastroenteritis in the united states and is acquired primarily through the ingestion of contaminated poultry products. here, we describe the c. jejuni orthologue of znua in other gram-negative bacteria. znua (cj0143c) is the periplasmic component of a putative zinc abc transport system and is encoded on a zinc-dependent operon with cj0142c and cj0141c, which encode the other two likely components of the transport system of c. jejuni. ...200919103921
antimicrobial susceptibility profiles and strain type diversity of campylobacter jejuni isolates from turkeys in eastern north carolina.campylobacter jejuni is one of the most common bacterial causes of human gastroenteritis, and recent findings suggest that turkeys are an important reservoir for this organism. in this study, 80 c. jejuni isolates from eastern north carolina were characterized for resistance to nine antimicrobials, and strain types were determined by fla typing, pulsed-field gel electrophoresis (pfge) with smai and kpni, and (for 41 isolates) multilocus sequence typing (mlst). pfge analysis suggested that many o ...200919028914
antimicrobial susceptibility profiles and strain type diversity of campylobacter jejuni isolates from turkeys in eastern north carolina.campylobacter jejuni is one of the most common bacterial causes of human gastroenteritis, and recent findings suggest that turkeys are an important reservoir for this organism. in this study, 80 c. jejuni isolates from eastern north carolina were characterized for resistance to nine antimicrobials, and strain types were determined by fla typing, pulsed-field gel electrophoresis (pfge) with smai and kpni, and (for 41 isolates) multilocus sequence typing (mlst). pfge analysis suggested that many o ...200919028914
dynamics of campylobacter colonization of a natural host, sturnus vulgaris (european starling).wild european starlings (sturnus vulgaris) shed campylobacter at high rates, suggesting that they may be a source of human and farm animal infection. a survey of campylobacter shedding of 957 wild starlings was undertaken by culture of faecal specimens and genetic analysis of the campylobacters isolated: shedding rates were 30.6% for campylobacter jejuni, 0.6% for c. coli and 6.3% for c. lari. genotyping by multilocus sequence typing (mlst) and antigen sequence typing established that these bact ...200918826435
quantifying transmission of campylobacter jejuni in commercial broiler flocks.since meat from poultry colonized with campylobacter spp. is a major cause of bacterial gastroenteritis, human exposure should be reduced by, among other things, prevention of colonization of broiler flocks. to obtain more insight into possible sources of introduction of campylobacter into broiler flocks, it is essential to estimate the moment that the first bird in a flock is colonized. if the rate of transmission within a flock were known, such an estimate could be determined from the change i ...200919047389
quantifying transmission of campylobacter jejuni in commercial broiler flocks.since meat from poultry colonized with campylobacter spp. is a major cause of bacterial gastroenteritis, human exposure should be reduced by, among other things, prevention of colonization of broiler flocks. to obtain more insight into possible sources of introduction of campylobacter into broiler flocks, it is essential to estimate the moment that the first bird in a flock is colonized. if the rate of transmission within a flock were known, such an estimate could be determined from the change i ...200919047389
oxidative stress-induced peptidoglycan deacetylase in helicobacter pylori.structural modification of peptidoglycan (pg) is one of the mechanisms that pathogenic bacteria use to evade the host innate immune system. for the noninvasive human gastric pathogen helicobacter pylori, pg delivery to the host cells is one trigger of the immune response. h. pylori hp310 was markedly up-expressed upon cell exposure to oxidative stress. however, disruption of hp310 did not produce a phenotype distinguishable from the parent, including oxidative stress resistance characteristics. ...200919147492
roles of lipooligosaccharide and capsular polysaccharide in antimicrobial resistance and natural transformation of campylobacter jejuni.this study is aimed to determine the role of capsular polysaccharide (cps) and lipooligosaccharide (los) in modulating antimicrobial resistance and natural transformation of campylobacter jejuni, an important food-borne human pathogen.200919147521
risk factors for campylobacter jejuni and campylobacter coli in young cattle on english and welsh farms.campylobacter jejuni and c. coli are the most prevalent causes of bacterial diarrhoea in most of the western world. in great britain, the source remains unknown for the majority of cases, though poultry is considered the main source of infection. molecular typing methods identify cattle as a potential source of a proportion of the non-source-attributed cases, mainly through direct contact, environmental contamination or milk, but little is known about the epidemiology of campylobacter in cattle. ...200918835052
a campylobacter jejuni znua orthologue is essential for growth in low-zinc environments and chick colonization.campylobacter jejuni infection is a leading cause of bacterial gastroenteritis in the united states and is acquired primarily through the ingestion of contaminated poultry products. here, we describe the c. jejuni orthologue of znua in other gram-negative bacteria. znua (cj0143c) is the periplasmic component of a putative zinc abc transport system and is encoded on a zinc-dependent operon with cj0142c and cj0141c, which encode the other two likely components of the transport system of c. jejuni. ...200919103921
campylobacter spp among children with acute diarrhea attending mulago hospital in kampala--uganda.campylobacter infections occur worldwide. a recent study in kampala, uganda, found that 87% of broiler chickens had campylobacter jejuni; these are potential source of human infection. isolation rate in developing countries is between 5-35%. this study aimed at finding prevalence of children with campylobacter infection among children with acute diarrhea attending mulago hospital.200920589152
[molecular investigation of relatedness of campylobacter coli isolated from child with campylobacteriosis and healthy, household dog].thermotolerant species of campylobacter (mainly c. jejuni and c. coli) are among the most frequently isolated bacterial agents of gastroenteritis in many developed countries. c. coli is less prevalent than c. jejuni. the main reservoir of c. coli is swine, however this pathogen may also be found in poultry, cattle and pets. genotypic methods have successfully been applied to the subtyping of campylobacter species in epidemiological investigation. in the present study we report a case of isolatio ...200920120926
prevalence of intestinal parasitic and bacterial pathogens in diarrhoeal and non-diarroeal human stools from vhembe district, south africa.in the present study, a cross-sectional survey of intestinal parasitic and bacterial infections in relation to diarrhoea in vhembe district and the antimicrobial susceptibility profiles of isolated bacterial pathogens was conducted. stool samples were collected from 528 patients attending major public hospitals and 295 children attending two public primary schools and were analyzed by standard microbiological and parasitological techniques. entamoeba histolytica/e. dispar (34.2%) and cryptospori ...200920099757
similarity of campylobacter coli from pigs, poultry and man.campylobacteriosis is one of the most frequently occurring acute gastroenteritis in humans and 10% are caused by campylobacter coli. a total of 136 isolates of c. coli from humans, poultry, and pigs were identified by multiplex polymerase chain reaction (pcr) and genetically characterized and compared by ribotyping. automatic riboprints were performed with the psti restriction enzyme and riboprinter. all poultry, pig and human strains represented a heterogeneous spectre of ribotypes. ten of 23 h ...200920183201
campylobacter excreted into the environment by animal sources: prevalence, concentration shed, and host association.an intensive study of 443 isolates of campylobacter jejuni and campylobacter coli from 2031 fecal samples excreted by animal sources including cattle, sheep, and pigs, a range of wild and domesticated avian species and pets is described. the prevalence found in the majority of animal sources ranged from 22% to 28% with poultry being highest at 41% and cats and dogs lowest (<5%). the average count excreted for each animal source was found not to be significantly different ranging from approximate ...200919839759
antimicrobial drug resistance as determined by the e-test in campylobacter jejuni, c. coli, and c. lari isolates from the ceca of broiler and layer chickens in grenada.one hundred and twenty five chickens from grenada, consisting of 77 broilers and 48 layers were examined for carriage of thermophilic campylobacters in their ceca by culture. seventy nine percent of chickens were positive for campylobacters, with an isolation rate of 93.5% for broilers and 56.3% for layers, the difference being significant. sixty-four pure cultures comprising 39 campylobacter coli, 21 campylobacter jejuni, and 4 campyilobacter lari isolates were tested for their resistance again ...200918329712
prevalence and patterns of antimicrobial resistance of fecal escherichia coil among pigs on 47 farrow-to-finish farms with different in-feed medication policies in ontario and british columbia.the main objectives of this study were to determine the prevalence and patterns of antimicrobial resistance in pigs on farms that medicated swine ration and those that did not. a total of 940 isolates of escherichia coli from 188 pooled fecal samples obtained from weaner and finisher pigs on 47 farrow-to-finish swine farms (34 farms used in-feed medication and 13 did not) were tested for susceptibility to 21 antimicrobials using a breakpoint concentration method. the prevalence of resistance var ...200818505210
the campylobacter jejuni thiol peroxidases tpx and bcp both contribute to aerotolerance and peroxide-mediated stress resistance but have distinct substrate specificities.the microaerophilic food-borne pathogen campylobacter jejuni experiences variable oxygen concentrations during its life cycle, especially during transitions between the external environment and the avian or mammalian gut. single knockout mutations in either one of two related thiol peroxidase genes, tpx and bcp, resulted in normal microaerobic growth (10% [vol/vol] oxygen) but poorer growth than that of the wild type under high-aeration conditions (21% [vol/vol] oxygen). however, a tpx/bcp doubl ...200818515414
prevalence of gastrointestinal bacterial pathogens in a population of zoo animals.faecal prevalence of gastrointestinal bacterial pathogens, including campylobacter, escherichia coli o157:h7, salmonella, shigella, yersinia, as well as arcobacter, were examined in 317 faecal specimens from 44 animal species in belfast zoological gardens, during july-september 2006. thermophilic campylobacters including campylobacter jejuni, campylobacter coli and campylobacter lari, were the most frequently isolated pathogens, where members of this genus were isolated from 11 animal species (1 ...200818331520
development and evaluation of a loop-mediated isothermal amplification assay for rapid and simple detection of campylobacter jejuni and campylobacter coli.we developed a loop-mediated isothermal amplification (lamp) assay for the rapid and simple detection of campylobacter jejuni and campylobacter coli. the assay provides a specific lamp product for each of these two species. the assay correctly identified 65 c. jejuni and 45 c. coli strains, but not 75 non-c. jejuni/coli strains. the sensitivity of the lamp assay for c. jejuni and c. coli in spiked human stool specimens was 5.6 x 10(3) c.f.u. g(-1) (1.4 c.f.u. per test tube) and 4.8 x 10(3) c.f.u ...200818349363
real-time pcr detection of pathogenic microorganisms in roof-harvested rainwater in southeast queensland, australia.in this study, the microbiological quality of roof-harvested rainwater was assessed by monitoring the concentrations of escherichia coli, enterococci, clostridium perfringens, and bacteroides spp. in rainwater obtained from tanks in southeast queensland, australia. samples were also tested using real-time pcr (with sybr green i dye) for the presence of potential pathogenic microorganisms. of the 27 rainwater samples tested, 17 (63%), 21 (78%), 13 (48%), and 24 (89%) were positive for e. coli, en ...200818621865
viral, bacterial and parasitic etiology of pediatric diarrhea in gaza, palestine.to determine the etiology of acute diarrhea in palestinian children under 5 years of age and to improve knowledge of the etiology of gastrointestinal pathogens using traditional and molecular diagnostic techniques.200818523397
host-pathogen interactions in campylobacter infections: the host perspective.campylobacter is a major cause of acute bacterial diarrhea in humans worldwide. this study was aimed at summarizing the current understanding of host mechanisms involved in the defense against campylobacter by evaluating data available from three sources: (i) epidemiological observations, (ii) observations of patients, and (iii) experimental observations including observations of animal models and human volunteer studies. analysis of available data clearly indicates that an effective immune syst ...200818625685
key role of mfd in the development of fluoroquinolone resistance in campylobacter jejuni.campylobacter jejuni is a major food-borne pathogen and a common causative agent of human enterocolitis. fluoroquinolones are a key class of antibiotics prescribed for clinical treatment of enteric infections including campylobacteriosis, but fluoroquinolone-resistant campylobacter readily emerges under the antibiotic selection pressure. to understand the mechanisms involved in the development of fluoroquinolone-resistant campylobacter, we compared the gene expression profiles of c. jejuni in th ...200818535657
campylobacter infection of broiler chickens in a free-range environment.campylobacter jejuni is the most common cause of bacterial gastroenteritis worldwide, with contaminated chicken meat considered to represent a major source of human infection. biosecurity measures can reduce c. jejuni shedding rates of housed chickens, but the increasing popularity of free-range and organic meat raises the question of whether the welfare benefits of extensive production are compatible with food safety. the widespread assumption that the free-range environment contaminates extens ...200818412548
identification of nine sequence types of the 16s rrna genes of campylobacter jejuni subsp. jejuni isolated from broilers.campylobacter is the most commonly reported bacterial cause of enteritis in humans in the eu member states and other industrialized countries. one significant source of infection is broilers and consumption of undercooked broiler meat. campylobacter jejuni is the campylobacter sp. predominantly found in infected humans and colonized broilers. sequence analysis of the 16s rrna gene is very useful for identification of bacteria to genus and species level. the objectives in this study were to deter ...200818492293
high-resolution genotyping of campylobacter species by use of pcr and high-throughput mass spectrometry.in this work we report on a high-throughput mass spectrometry-based technique for the rapid high-resolution identification of campylobacter jejuni strain types. this method readily distinguishes c. jejuni from c. coli, has a resolving power comparable to that of multilocus sequence typing (mlst), is applicable to mixtures, and is highly automated. the strain typing approach is based on high-performance mass spectrometry, which "weighs" pcr amplicons with enough mass accuracy to unambiguously det ...200818272701
production of a monoclonal antibody specific for the major outer membrane protein of campylobacter jejuni and characterization of the epitope.campylobacter species are important enteric pathogens causing disease in humans and animals. there is a lack of a good immunological test that can be used routinely to separate campylobacter jejuni from other campylobacter species. we produced monoclonal antibodies (mabs) directed against the major outer membrane protein (momp) of c. jejuni using recombinant momp as the antigen. one mab, designated mab5c4 and of the immunoglobulin g1 isotype, was found to be potentially specific for c. jejuni. d ...200818065632
production of a monoclonal antibody specific for the major outer membrane protein of campylobacter jejuni and characterization of the epitope.campylobacter species are important enteric pathogens causing disease in humans and animals. there is a lack of a good immunological test that can be used routinely to separate campylobacter jejuni from other campylobacter species. we produced monoclonal antibodies (mabs) directed against the major outer membrane protein (momp) of c. jejuni using recombinant momp as the antigen. one mab, designated mab5c4 and of the immunoglobulin g1 isotype, was found to be potentially specific for c. jejuni. d ...200818065632
occurrence and genotypes of campylobacter in broiler flocks, other farm animals, and the environment during several rearing periods on selected poultry farms.on 15 swiss poultry farms, broiler flocks, other farm animals, and the environment were examined during consecutive rearing periods to investigate the occurrence and genetic diversity of campylobacter. of the 5154 collected samples, 311 (6%) from 14 farms were campylobacter positive by culture. amongst the positive samples, 228 tested positive for campylobacter jejuni and 92 for campylobacter coli. positive samples originated from broilers, the broiler houses, cattle, pigs, bantams, laying hens, ...200818508146
development of a strain-specific molecular method for quantitating individual campylobacter strains in mixed populations.the identification of sites resulting in cross-contamination of poultry flocks in the abattoir and determination of the survival and persistence of campylobacters at these sites are essential for the development of intervention strategies aimed at reducing the microbial burden on poultry at retail. a novel molecule-based method, using strain- and genus-specific oligonucleotide probes, was developed to detect and enumerate specific campylobacter strains in mixed populations. strain-specific oligo ...200818281428
comparison of antimicrobial resistance of campylobacter jejuni and campylobacter coli isolated from humans and chicken carcasses in poland.campylobacter-associated gastroenteritis remains an important cause of morbidity worldwide, and some evidence suggests that poultry is an important source of this foodborne infection in humans. this study was conducted to analyze the prevalence and genetic background of resistance of 149 campylobacter jejuni and 54 campylobacter coli strains isolated from broiler chicken carcasses and from stool samples of infected children in poland from 2003 through 2005. nearly all isolates were susceptible t ...200818389707
harmonised monitoring of antimicrobial resistance in salmonella and campylobacter isolates from food animals in the european union.many member states of the european union (eu) currently monitor antimicrobial resistance in zoonotic agents, including salmonella and campylobacter. according to directive 2003/99/ec, member states shall ensure that the monitoring provides comparable data on the occurrence of antimicrobial resistance. the european commission asked the european food safety authority to prepare detailed specifications for harmonised schemes for monitoring antimicrobial resistance. the objective of these specificat ...200818397331
ccaat/enhancer binding protein beta is a major mediator of inflammation and viral replication in the gastrointestinal tract of simian immunodeficiency virus-infected rhesus macaques.the gastrointestinal tract (git) is a major target of infection with human immunodeficiency virus (hiv) and simian immunodeficiency virus (siv). chronic git disease and inflammation are common sequelae to hiv/siv infection. nonetheless, the molecular mechanisms that cause and maintain git dysfunction remain unclear. we investigated the contribution of ccaat/enhancer-binding protein beta (c/ebpbeta) to git disease and viral replication in jejunum and colon collected at necropsy from 12 siv-infect ...200818535173
campylobacter jejuni survives within epithelial cells by avoiding delivery to lysosomes.campylobacter jejuni is one of the major causes of infectious diarrhea world-wide, although relatively little is know about its mechanisms of pathogenicity. this bacterium can gain entry into intestinal epithelial cells, which is thought to be important for its ability to persistently infect and cause disease. we found that c. jejuni is able to survive within intestinal epithelial cells. however, recovery of intracellular bacteria required pre-culturing under oxygen-limiting conditions, suggesti ...200818225954
competing isogenic campylobacter strains exhibit variable population structures in vivo.consumption of poultry contaminated with campylobacter jejuni is a risk factor for human gastrointestinal disease. the rational development of control strategies for campylobacter within chickens requires an understanding of the colonization process at the molecular and population levels, both within and between hosts. experiments employing competing strains of campylobacter have been used to investigate colonization. implicit in these studies is the assumption that the behavior of competing str ...200818424530
Refresh
firstprev
12345678910...
nextlast
Displaying items 901 - 1000 of 2341