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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
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
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
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
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
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
can campylobacter coli induce guillain-barré syndrome? 200919002726
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 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
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
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
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
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
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
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
[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
occurrence of thermophilic campylobacter spp. contamination on vegetable farms in malaysia.the aim of the present study was to examine the prevalence of thermophilic campylobacter spp. (campylobacter jejuni and campylobacter coli) in soil, poultry manure, irrigation water, and freshly harvested vegetables from vegetable farms in malaysia. c. jejuni was detected in 30.4% and 2.7% of the soil samples, 57.1% and 0% of the manure samples, and 18.8% and 3% of the vegetable samples from farm a and farm b, respectively, when using the mpnpcr method. campylobacter spp. was not found in any of ...200919996696
resistance to antimicrobial agents of campylobacter spp. strains isolated from animals in poland.a total of 69 campylobacter jejuni and 16 campylobacter coli strains isolated from chicken, dog and pig stool samples were characterized based on their resistance to five antimicrobial agents and on plasmid ptet profiles. antimicrobials used in this study were: amoxicillin/clavulanic acid, ciprofloxacin, erythromycin, tetracycline and trimethoprim/sulfamethoxazole. among the isolates studied, 91.7% were resistant to one or more antimicrobial agent. the highest level of resistance for the whole t ...200920169919
[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
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
prevalence and risk factor investigation of campylobacter species in beef cattle feces from seven large commercial feedlots in alberta, canada.this fecal prevalence study targeted cattle from 7 large (10,000 to > 40,000 head) commercial feedlots in alberta as a means of establishing campylobacter levels in cattle just prior to animals entering the food chain. overall, 87% [95% confidence interval (ci) = 86-88] of 2776 fresh pen-floor fecal samples were culture positive for campylobacter species, with prevalences ranging from 76% to 95% among the 7 feedlots. campylobacter spp. prevalence was 88% (95% ci = 86-90) in the summer (n = 1376) ...200920046629
helicobacter pylori lipopolysaccharide modification, lewis antigen expression, and gastric colonization are cholesterol-dependent.helicobacter pylori specifically takes up cholesterol and incorporates it into the bacterial membrane, yet little is currently known about cholesterol's physiological roles. we compared phenotypes and in vivo colonization ability of h. pylori grown in a defined, serum-free growth medium, f12 with 1 mg/ml albumin containing 0 to 50 mug/ml cholesterol.200920003432
the hemolytic and cytolytic activities of serratia marcescens phospholipase a (phla) depend on lysophospholipid production by phla.serratia marcescens is a gram-negative bacterium and often causes nosocomial infections. there have been few studies of the virulence factors of this bacterium. the only s. marcescens hemolytic and cytotoxic factor reported, thus far, is the hemolysin shla.200920003541
easy-to-use rapid test for direct detection of campylobacter spp. in chicken feces.human campylobacteriosis is the leading cause of acute bacterial gastroenteritis in developed countries. one important source of infection is poultry. results from the dutch campylobacter risk management and assessment project indicate that meat from broiler flocks shedding >or=7 log cfu campylobacter per g of feces poses the greatest risk of transmitting campylobacteriosis. the objective of this study was to develop a simple and rapid test that would identify chicken flocks shedding high number ...200920003729
description and sources of contamination by campylobacter spp. of river water destined for human consumption in brittany, france.presence or absence of campylobacter spp. in water of five rivers upstream from an intake point for drinking water production was investigated, and isolates genetically compared with human, pig and poultry isolates in order to determine their source. river water and drinking water obtained from these rivers were sampled one time per month, over a period of one year, and tested for campylobacter. isolates were typed by pfge. campylobacter was not detected in treated drinking water, but 50% of the ...200919942377
efficacy of mini vidas for the detection of campylobacter spp. from retail broiler meat enriched in bolton broth, with or without the supplementation of blood.the goals of this study were to evaluate the efficacy of the mini vidas automated immunoassay chemistry system to detect campylobacter spp. from retail broiler meat enriched in bolton broth supplemented with lysed blood (b+b) or without blood (b-b), and to detect positive samples at 24 versus 48 h after enrichment. retail broiler meat was enriched and tested for campylobacter spp. with the mini vidas and with an agar plate. isolates were speciated with a multiplex pcr and typed with pulsed-field ...200919903413
campylobacter species occurrence within internal organs and tissues of commercial caged leghorn laying hens.campylobacter spp. are frequently present in the intestinal tract and internal tissues of broiler breeder and broiler chickens. campylobacter spp. ecology in commercial leghorn laying hens has not been extensively studied. the objectives of the current study were to determine 1) campylobacter spp. presence in the reproductive tract, lymphoid organs, liver-gallbladder, and ceca of commercial leghorn laying hens; 2) species of campylobacter present; and 3) antimicrobial resistance pattern of campy ...200919834099
characterization of the oxidative stress stimulon and perr regulon of campylobacter jejuni.during gut colonization, the enteric pathogen campylobacter jejuni must surmount the toxic effects of reactive oxygen species produced by its own metabolism, the host immune system, and intestinal microflora. elucidation of c. jejuni oxidative stress defense mechanisms is critical for understanding campylobacter pathophysiology.200919835633
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
long-term survival of campylobacter jejuni at low temperatures is dependent on polynucleotide phosphorylase activity.campylobacter jejuni is a leading cause of bacterial gastroenteritis worldwide. infection generally occurs after ingestion of contaminated poultry products, usually conserved at low temperatures. the mechanisms promoting survival of c. jejuni in the cold remain poorly understood despite several investigations. the present study provides insight into the survival mechanism by establishing the involvement of polynucleotide phosphorylase (pnpase), a 3'-5' exoribonuclease with multiple biological fu ...200919801468
functional analysis of the helicobacter pylori flagellar switch proteins.helicobacter pylori uses flagellum-mediated chemotaxis to promote infection. bacterial flagella change rotational direction by changing the state of the flagellar motor via a subcomplex referred to as the switch. intriguingly, the h. pylori genome encodes four switch complex proteins, flim, flin, fliy, and flig, instead of the more typical three of escherichia coli or bacillus subtilis. our goal was to examine whether and how all four switch proteins participate in flagellation. previous work de ...200919767432
prevalence of campylobacter spp. in raw retail poultry on sale in northern ireland.a year-long survey of fresh, retail poultry products on sale in northern ireland was undertaken to define the prevalence of campylobacter spp. by using protocols based on iso (standard) 10272-1:2006. incubation at 37 and 42 degrees c was undertaken to increase the diversity of isolates obtained. overall, 652 isolates were identified as campylobacter spp. by using pcr and amplified fragment length polymorphic typing. phenotyping wrongly identified 21% of isolates. prevalences of campylobacter fou ...200919777882
molecular, antigenic, and functional characteristics of ferric enterobactin receptor cfra in campylobacter jejuni.the ferric enterobactin receptor cfra not only is responsible for high-affinity iron acquisition in campylobacter jejuni but also is essential for c. jejuni colonization in animal intestines. in this study, we determined the feasibility of targeting the iron-regulated outer membrane protein cfra for immune protection against campylobacter colonization. alignment of complete cfra sequences from 15 campylobacter isolates showed that the levels of amino acid identity for cfra range from 89% to 98%. ...200919737895
genetic diversity and stability of the pora allele as a genetic marker in human campylobacter infection.the major outer-membrane protein (momp) of campylobacter jejuni and campylobacter coli, encoded by the pora gene, is extremely genetically diverse. conformational momp epitopes are important in host immunity, and variation in surface-exposed regions probably occurs as a result of positive immune selection during infection. pora diversity has been exploited in genotyping studies using highly discriminatory nucleotide sequences to identify potentially epidemiologically linked cases of human campyl ...200919744989
cost analysis and antimicrobial susceptibility testing comparing the e test and the agar dilution method in campylobacter jejuni and campylobacter coli.although numerous reports have compared the antimicrobial susceptibility of campylobacter spp., controversy still exists about the use of the e test as an alternative to the agar dilution method suggested by the clinical and laboratory standards institute. mics of 8 antimicrobials were determined using the e test and agar dilution methods for 103 campylobacter jejuni and campylobacter coli isolates from fresh chicken randomly purchased from stores in 3 southern ontario counties. overall, 72.6% o ...200919748428
functional characterization of flagellin glycosylation in campylobacter jejuni 81-176.the major flagellin of campylobacter jejuni strain 81-176, flaa, has been shown to be glycosylated at 19 serine or threonine sites, and this glycosylation is required for flagellar filament formation. some enzymatic components of the glycosylation machinery of c. jejuni 81-176 are localized to the poles of the cell in an flhf-independent manner. flagellin glycosylation could be detected in flagellar mutants at multiple levels of the regulatory hierarchy, indicating that glycosylation occurs inde ...200919749047
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
thermotolerant coliforms are not a good surrogate for campylobacter spp. in environmental water.this study aimed to assess the importance of quantitatively detecting campylobacter spp. in environmental surface water. the prevalence and the quantity of campylobacter spp., thermotolerant coliforms, and escherichia coli in 2,471 samples collected weekly, over a 2-year period, from 13 rivers and 12 streams in the eastern townships, québec, canada, were determined. overall, 1,071 (43%), 1,481 (60%), and 1,463 (59%) samples were positive for campylobacter spp., thermotolerant coliforms, and e. c ...200919734335
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
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 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
susceptibility of campylobacter jejuni and campylobacter coli isolated from animals and humans to ciprofloxacin.fifty five thermophilic campylobacter spp. strains were isolated from the caecum of broilers, cecum and colon of pigs and from human faeces. the strains were identified as campylobacter jejuni and campylobacter coli. the more prevalent species in humans and broilers was campylobacter jejuni, and in pigs campylobacter coli. in the framework of this study, sensitivity to ciprofloxacin in isolated strains of campylobacter jejuni and campylobacter coli was tested by e-test. resistant to ciprofloxaci ...200919645360
the response of campylobacter jejuni to low temperature differs from that of escherichia coli.human infection with campylobacter jejuni is often associated with the consumption of foods that have been exposed to both chilling and high temperatures. despite the public health importance of this pathogen, little is known about the effects of cold exposure on its ability to survive a subsequent heat challenge. this work examined the effect of rapid exposure to chilling, as would occur in poultry processing, on the heat resistance at 56 degrees c of two c. jejuni strains, 11168 and 2097e48, a ...200919648365
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
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
campylobacter coli prosthetic hip infection associated with ingestion of contaminated oysters.this report describes the first reported case of a prosthetic hip joint infection due to campylobacter coli. the infection presumably resulted from ingestion of contaminated raw oysters. issues regarding original smear interpretation, culture isolation, and susceptibility testing are presented.200919656982
efflux-mediated drug resistance in bacteria: an update.drug efflux pumps play a key role in drug resistance and also serve other functions in bacteria. there has been a growing list of multidrug and drug-specific efflux pumps characterized from bacteria of human, animal, plant and environmental origins. these pumps are mostly encoded on the chromosome, although they can also be plasmid-encoded. a previous article in this journal provided a comprehensive review regarding efflux-mediated drug resistance in bacteria. in the past 5 years, significant pr ...200919678712
spatiotemporal homogeneity of campylobacter subtypes from cattle and sheep across northeastern and southwestern scotland.source attribution using molecular subtypes has implicated cattle and sheep as sources of human campylobacter infection. whether the campylobacter subtypes associated with cattle and sheep vary spatiotemporally remains poorly known, especially at national levels. here we describe spatiotemporal patterns of prevalence, bacterial enumeration, and subtype composition in campylobacter isolates from cattle and sheep feces from northeastern (63 farms, 414 samples) and southwestern (71 farms, 449 sampl ...200919700557
multiplex strategy for multilocus sequence typing, fla typing, and genetic determination of antimicrobial resistance of campylobacter jejuni and campylobacter coli isolates collected in switzerland.we present an optimized multilocus sequence typing (mlst) scheme with universal primer sets for amplifying and sequencing the seven target genes of campylobacter jejuni and campylobacter coli. typing was expanded by sequence determination of the genes flaa and flab using optimized primer sets. this approach is compatible with the mlst and flaa schemes used in the pubmlst database and results in an additional typing method using the flab gene sequence. an identification module based on the 16s rr ...200919439549
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
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
[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
[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
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
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
genomic insights into the convergence and pathogenicity factors of campylobacter jejuni and campylobacter coli species.whether or not bacteria form coherent evolutionary groups via means of genetic exchange and, hence, elicit distinct species boundaries remains an unsettled issue. a recent report implied that not only may the former be true but also, in fact, the clearly distinct campylobacter jejuni and campylobacter coli species may be converging as a consequence of increased interspecies gene flow fostered, presumably, by the recent invasion of an overlapping ecological niche (s. k. sheppard, n. d. mccarthy, ...200919617370
prokaryotic protein glycosylation is rapidly expanding from "curiosity" to "ubiquity". 200919621412
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
campylobacter jejuni in penguins, antarctica. 200919402996
novel campylobacter lari-like bacteria from humans and molluscs: description of campylobacter peloridis sp. nov., campylobacter lari subsp. concheus subsp. nov. and campylobacter lari subsp. lari subsp. nov.a polyphasic study was undertaken to clarify the taxonomic position of campylobacter lari-like strains isolated from shellfish and humans. the diversity within the strain collection was initially screened by means of fluorescent amplified fragment length polymorphism analysis and whole-cell protein electrophoresis, revealing the existence of two clusters distinct from c. lari and other campylobacter species. the divergence of these clusters was confirmed by phenotypic analysis and by 16s rrna an ...200919406805
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
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
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
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
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
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
multiplex pcr to diagnose bloodstream infections in patients admitted from the emergency department with sepsis.sepsis is caused by a heterogeneous group of infectious etiologies. early diagnosis and the provision of appropriate antimicrobial therapy correlate with positive clinical outcomes. current microbiological techniques are limited in their diagnostic capacities and timeliness. multiplex pcr has the potential to rapidly identify bloodstream infections and fill this diagnostic gap. we identified patients from two large academic hospital emergency departments with suspected sepsis. the results of a m ...200919846634
multiplex pcr to diagnose bloodstream infections in patients admitted from the emergency department with sepsis.sepsis is caused by a heterogeneous group of infectious etiologies. early diagnosis and the provision of appropriate antimicrobial therapy correlate with positive clinical outcomes. current microbiological techniques are limited in their diagnostic capacities and timeliness. multiplex pcr has the potential to rapidly identify bloodstream infections and fill this diagnostic gap. we identified patients from two large academic hospital emergency departments with suspected sepsis. the results of a m ...200919846634
occurrence of campylobacter jejuni and campylobacter coli and their biotypes in beef and dairy cattle from the south of chile.the prevalence of campylobacter jejuni and campylobacter coli and their biotypes in beef and dairy cattle from the south of chile was established. campylobacter were statistically more prevalent among beef cattle (35.9%) than among dairy cattle (21.3%), being c. jejuni the species most frequently isolated.200924031386
rapid identification of bacterial pathogens using a pcr- and microarray-based assay.during the course of a bacterial infection, the rapid identification of the causative agent(s) is necessary for the determination of effective treatment options. we have developed a method based on a modified broad-range pcr and an oligonucleotide microarray for the simultaneous detection and identification of 12 bacterial pathogens at the species level. the broad-range pcr primer mixture was designed using conserved regions of the bacterial topoisomerase genes gyrb and pare. the primer design a ...200919664269
comprehensive and rapid real-time pcr analysis of 21 foodborne outbreaks.a set of four duplex sybr green i pcr (sg-pcr) assay combined with dna extraction using qiaamp dna stool mini kit was evaluated for the detection of foodborne bacteria from 21 foodborne outbreaks. the causative pathogens were detected in almost all cases in 2 hours or less. the first run was for the detection of 8 main foodborne pathogens in 5 stool specimens within 2 hours and the second run was for the detection of other unusual suspect pathogens within a further 45 minutes. after 2 to 4 days, ...200920016673
drug efflux pump deficiency and drug target resistance masking in growing bacteria.recent experiments have shown that drug efflux pump deficiency not only increases the susceptibility of pathogens to antibiotics, but also seems to "mask" the effects of mutations, that decrease the affinities of drugs to their intracellular targets, on the growth rates of drug-exposed bacteria. that is, in the presence of drugs, the growth rates of drug-exposed wt and target mutated strains are the same in a drug efflux pump deficient background, but the mutants grow faster than wt in a drug ef ...200919416855
campylobacter enteritis in children in northern taiwan--a 7-year experience.campylobacter infection is recognized as a major cause of acute enteritis in humans. the clinical characteristics may vary in different countries. this study investigated the clinical manifestations of pediatric campylobacter enteritis in a medical center in northern taiwan.200819122923
antimicrobial resistance in selected bacteria from poultry.this paper reviews the present state of antimicrobial resistance (amr) in the zoonotic bacteria salmonella, campylobacter jejuni and campylobacter coli, and in escherichia coli from chickens and turkeys. for salmonella, the frequencies and patterns of amr vary depending on time, region, serovar, the particular farm, layers versus broilers, and the antimicrobial agent. there is usually a higher frequency of amr in salmonella from turkeys compared with salmonella from chickens. clonal and horizont ...200819102788
case-case analysis of enteric diseases with routine surveillance data: potential use and example results.case-control studies and outbreak investigations are the major epidemiological tools for providing detailed information on enteric disease sources and risk factors, but these investigations can be constrained by cost and logistics.200818976484
dna mimics for the rapid identification of microorganisms by fluorescence in situ hybridization (fish).fluorescence in situ hybridization (fish) is a well-established technique that is used for a variety of purposes, ranging from pathogen detection in clinical diagnostics to the determination of chromosomal stability in stem cell research. the key step of fish involves the detection of a nucleic acid region and as such, dna molecules have typically been used to probe for the sequences of interest. however, since the turn of the century, an increasing number of laboratories have started to move on ...200819325728
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
evaluation of 16s rrna gene-based pcr assays for genus-level identification of helicobacter species.the inclusivity, exclusivity, and detection limit of six 16s rrna gene-based helicobacter genus-specific pcr assays were examined. five out of six assays were 100% inclusive, but the tests varied considerably in their exclusivity (9.1 to 95.5%). the clinical detection limit varied between 10(3) and 1 viable bacterial cell per reaction mixture.200818337392
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
sequence variability of campylobacter temperate bacteriophages.prophages integrated within the chromosomes of campylobacter jejuni isolates have been demonstrated very recently. prior work with campylobacter temperate bacteriophages, as well as evidence from prophages in other enteric bacteria, suggests these prophages might have a role in the biology and virulence of the organism. however, very little is known about the genetic variability of campylobacter prophages which, if present, could lead to differential phenotypes in isolates carrying the phages ve ...200818366706
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
comparison of campylobacter populations in wild geese with those in starlings and free-range poultry on the same farm.wild geese are a potential source of campylobacter infection for humans and farm animals and have been implicated in at least two large waterborne disease outbreaks. there have been few investigations into the population biology of campylobacter in geese, carriage rates are reported to vary (0 to 100%), and no genetic characterization of isolates has been performed. fecal samples collected from wild geese in oxfordshire, united kingdom, were culture positive for c. jejuni (50.2%) and c. coli (0. ...200818390684
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
convergence of campylobacter species: implications for bacterial evolution.the nature of species boundaries in bacteria remains controversial. in particular, the mechanisms of bacterial speciation and maintenance in the face of frequent genetic exchange are poorly understood. here, we report patterns of genetic exchange that show two closely related zoonotic pathogenic species, campylobacter jejuni and campylobacter coli, are converging as a consequence of recent changes in gene flow. population expansion into a novel ecological niche generated by human activity is the ...200818403712
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
sexual dimorphism in campylobacteriosis.sexual dimorphism in infectious diseases whereby disease incidence is more prevalent in one gender has been reported repeatedly in the scientific literature. both behavioural and physiological differences have been suggested as a cause of this gender bias but there is a paucity of data to support either of these viewpoints. here it is hypothesized that for campylobacteriosis physiological factors play an important role in the higher incidence in males. we demonstrate in the human population (fro ...200818062834
sexual dimorphism in campylobacteriosis.sexual dimorphism in infectious diseases whereby disease incidence is more prevalent in one gender has been reported repeatedly in the scientific literature. both behavioural and physiological differences have been suggested as a cause of this gender bias but there is a paucity of data to support either of these viewpoints. here it is hypothesized that for campylobacteriosis physiological factors play an important role in the higher incidence in males. we demonstrate in the human population (fro ...200818062834
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
survey of campylobacter jejuni in stray cats in southern italy.to evaluate the presence of thermotolerant campylobacter spp. in stray cats in southern italy.200818069980
lack of response of int-407 cells to the presence of non-culturable campylobacter jejuni.many contradictory articles on the infectivity of non-culturable campylobacter jejuni can be found. we studied the effect of non-culturable c. jejuni in an in vitro assay. to prevent the potential effect of a few culturable bacteria in the non-culturable suspension, int-407 cells, which mimic the outer cell layer in the small intestines, were exposed to culturable c. jejuni suspensions with or without non-culturable c. jejuni. the number of bacteria adhering to and/or invading int-407 cells and ...200818081950
lack of response of int-407 cells to the presence of non-culturable campylobacter jejuni.many contradictory articles on the infectivity of non-culturable campylobacter jejuni can be found. we studied the effect of non-culturable c. jejuni in an in vitro assay. to prevent the potential effect of a few culturable bacteria in the non-culturable suspension, int-407 cells, which mimic the outer cell layer in the small intestines, were exposed to culturable c. jejuni suspensions with or without non-culturable c. jejuni. the number of bacteria adhering to and/or invading int-407 cells and ...200818081950
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