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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
retrospective study of campylobacter infection in a zoological collection.little is known about the epidemiology of campylobacter spp. in wild animal populations. however, zoological collections can provide valuable insights. using records from the zoological society of london whipsnade zoo compiled between 1990 and 2003, the roles of a range of biotic and abiotic factors associated with the occurrence of campylobacteriosis were investigated. the occurrence of campylobacteriosis varied widely across host taxonomic orders. furthermore, in mammals, a combination of chan ...200818165368
retrospective study of campylobacter infection in a zoological collection.little is known about the epidemiology of campylobacter spp. in wild animal populations. however, zoological collections can provide valuable insights. using records from the zoological society of london whipsnade zoo compiled between 1990 and 2003, the roles of a range of biotic and abiotic factors associated with the occurrence of campylobacteriosis were investigated. the occurrence of campylobacteriosis varied widely across host taxonomic orders. furthermore, in mammals, a combination of chan ...200818165368
role of campylobacter jejuni respiratory oxidases and reductases in host colonization.campylobacter jejuni is the leading cause of human food-borne bacterial gastroenteritis. the c. jejuni genome sequence predicts a branched electron transport chain capable of utilizing multiple electron acceptors. mutants were constructed by disrupting the coding regions of the respiratory enzymes nitrate reductase (napa::cm), nitrite reductase (nrfa::cm), dimethyl sulfoxide, and trimethylamine n-oxide reductase (termed cj0264::cm) and the two terminal oxidases, a cyanide-insensitive oxidase (cy ...200818192421
real-time pcr approach for detection of environmental sources of campylobacter strains colonizing broiler flocks.reducing colonization of poultry flocks by campylobacter spp. is a key strategy in the control and prevention human campylobacteriosis. horizontal transmission of campylobacters, from in and around the farm, is the presumed route of flock colonization. however, the identification and prioritization of sources are confounded by the ubiquitous nature of these organisms in the environment, their poor rates of recovery by standard culture methods, and the need for cost-effective and timely methods f ...200818203857
risk factors for infection with campylobacter jejuni flaa genotypes.we aimed to explore campylobacter genotype-specific risk factors in australia. isolates collected prospectively from cases recruited into a case-control study were genotyped using flaa restriction fragment-length polymorphism typing (flaa genotyping). exposure information for cases and controls was collected by telephone interview. risk factors were examined for major flaa genotypes using logistic and multinomial regression. five flaa genotypes accounted for 325 of 590 (55%) cases - flaa-6b (n=1 ...200818205975
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
the origin of a novel gene through overprinting in escherichia coli.overlapped genes originate by a) loss of a stop codon among contiguous genes coded in different frames; b) shift to an upstream initiation codon of one of the contiguous genes; or c) by overprinting, whereby a novel open reading frame originates through point mutation inside an existing gene. although overlapped genes are common in viruses, it is not clear whether overprinting has led to new genes in prokaryotes.200818226237
functional characterization and mutagenesis of the proposed behavioral sensor tlpd of helicobacter pylori.helicobacter pylori requires flagellar motility and chemotaxis to establish and maintain chronic infection of the human stomach. the ph gradient in the stomach mucus is essential for bacterial orientation and guides the bacterium toward a narrow layer of the mucus, suggesting that h. pylori is capable of energy sensing or taxis. in the present study, h. pylori wild-type behavior in a temporal swimming assay could be altered by electron transport inhibitors, indicating that a connection between m ...200818245281
development of a cytolethal distending toxin (cdt) gene-based species-specific multiplex pcr assay for the detection and identification of campylobacter jejuni, campylobacter coli and campylobacter fetus.a cytolethal distending toxin (cdt) gene-based species-specific multiplex pcr assay for the detection of cdta, cdtb or cdtc gene of campylobacter jejuni, campylobacter coli or campylobacter fetus, respectively, was developed and evaluated with 76 campylobacter strains belonging to seven different species and 131 other bacterial strains of eight different genera. the cdta, cdtb or cdtc gene of c. jejuni, c. coli or c. fetus, respectively, could be successfully amplified using the corresponding se ...200818248435
development and evaluation of immunochromatographic assay for simple and rapid detection of campylobacter jejuni and campylobacter coli in human stool specimens.an immunochromatographic assay (campy-ica) using a newly generated single monoclonal antibody against a 15-kda cell surface protein of campylobacter jejuni was developed. when cell suspensions of 86 c. jejuni strains and 27 campylobacter coli strains were treated with a commercially available bacterial protein extraction reagent and the resulting extracts were tested with the campy-ica, they all yielded positive results. the minimum detectable limits for the c. jejuni strains ranged from 1.8 x 1 ...200818256225
comparative performance of different pcr assays for the identification of campylobacter jejuni and campylobacter coli.the sensitivity and specificity of 7 pcr assays described for the identification of campylobacter jejuni and campylobacter coli were examined using alkaline cell lysates from a collection of 100 well characterized reference strains of c. jejuni, c. coli, campylobacter lari and related campylobacter, helicobacter and arcobacter species. based on a preliminary evaluation, one multiplex test was excluded from further evaluation. the various assays differed considerably in sensitivity and specificit ...200818272350
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
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
a temperature-regulated campylobacter jejuni gluconate dehydrogenase is involved in respiration-dependent energy conservation and chicken colonization.campylobacter jejuni is a gastrointestinal pathogen of humans but can asymptomatically colonize the avian gut. c. jejuni therefore grows at both 37 degrees c and 42 degrees c, the internal temperatures of humans and birds respectively. microarray and proteomic studies on temperature regulation in c. jejuni strain 81-176 revealed the upregulation at 42 degrees c of two proteins, cj0414 and cj0415, orthologous to gluconate dehydrogenase (gadh) from pectobacterium cypripedii. 81-176 demonstrated ga ...200818284594
differences in virulence attributes between cytolethal distending toxin positive and negative campylobacter jejuni strains.campylobacter jejuni is a common gastrointestinal bacterial pathogen. although cytolethal distending toxin (cdt) is proposed to be an important virulence determinant of this pathogen, how cdt(+) and cdt(-) strains differ in their biological properties remains largely unknown. the virulence properties of cdt(+) and cdt(-) strains were studied on hela cells and in the suckling mouse model. presence of the cdtb gene in campylobacter species was determined by pcr. five each of cdt(+) and cdt(-) c. j ...200818287287
prevalence of virulence genes and cytolethal distending toxin production in campylobacter jejuni isolates from diarrheal patients in bangladesh.from 300 stool samples, 58 campylobacter strains were isolated by standard microbiological and biochemical methods. of these, 40 strains were identified as campylobacter jejuni and 5 as campylobacter coli. the presence of flaa (100%), cadf (100%), racr (100%), dnaj (100%), plda (100%), ciab (95%), virb11 (0%), ceue (82.5%), cdta (97.5%), cdtb (97.5%), cdtc (97.5%), and wlan (7.5%) genes was detected in c. jejuni by pcr. all c. jejuni strains but one produced cytolethal distending toxin in a hela ...200818287317
antimicrobial resistance of campylobacter spp. isolated from broiler flocks in iceland 2001-2005.minimum inhibitory concentrations of six antimicrobial agents were determined for one campylobacter sp. isolate from each of the 362 campylobacter-positive commercial chicken flocks in iceland in the years 2001-2005. of all isolates tested, 6.9% were resistant, although none were multiresistant. resistance to ampicillin was most commonly observed (3.6%) followed by resistance to enrofloxacin (3%), nalidixic acid (1.9%), and oxytetracyclin (0.3%), with cross-resistance between enrofloxacin and na ...200818321203
wide geographical distribution of internationally rare campylobacter clones within new zealand.during the southern hemisphere winter of 2006 new zealand experienced a significant increase in the number of reported cases of campylobacter infection. in total, 112 campylobacter isolates from eight district health boards (dhbs) located across new zealand were submitted for pfge, mlst and penner serotyping analysis. distinct clusters of campylobacter isolates were identified, several of which were composed of isolates from up to five different dhbs located on both the north and south islands o ...200818028582
wide geographical distribution of internationally rare campylobacter clones within new zealand.during the southern hemisphere winter of 2006 new zealand experienced a significant increase in the number of reported cases of campylobacter infection. in total, 112 campylobacter isolates from eight district health boards (dhbs) located across new zealand were submitted for pfge, mlst and penner serotyping analysis. distinct clusters of campylobacter isolates were identified, several of which were composed of isolates from up to five different dhbs located on both the north and south islands o ...200818028582
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
multilocus sequence typing, pulsed-field gel electrophoresis, and fla short variable region typing of clonal complexes of campylobacter jejuni strains of human, bovine, and poultry origins in luxembourg.campylobacter jejuni is the most common cause of bacterial gastroenteritis in luxembourg, with a marked seasonal peak during summer. the majority of these infections are thought to be sporadic, and the relative contribution of potential sources and reservoirs is still poorly understood. we monitored human cases from june to september 2006 (n = 124) by molecular characterization of isolates with the aim of rapidly detecting temporally related cases. in addition, isolates from poultry meat (n = 36 ...200818931296
influence of long time storage in mineral water on rna stability of pseudomonas aeruginosa and escherichia coli after heat inactivation.research of rna viability markers was previously studied for many bacterial species. few and different targets of each species have been checked and motley results can be found in literature. no research has been done about pseudomonas aeruginosa in this way.200818941615
antimicrobial resistance of campylobacter coli isolates from swine.eighty-three swine isolates of campylobacter coli were tested for mechanisms underlying resistance to nalidixic acid, ciprofloxacin, erythromycin and tetracycline. four isolates harbored class 1 integrons but none carried class 2 and 3 integrons. most of the tetracycline-resistant isolates (97%) possessed tet(o). a thr-86-ile substitution in gyra and an a-2230-g mutation in 23s rrna were the main resistance mechanisms for quinolones and erythromycin, respectively.200818945505
pediatric campylobacteriosis in northern taiwan from 2003 to 2005.there has been a marked increase in the incidence of, and concern regarding, human campylobacter jejuni and c. coli infections worldwide during the last decade. as the highest infectious disease control apparatus in taiwan, we aimed to describe the character of campylobacter isolates from infected children, as well as basic information about the patients, from december 2003 to february 2005.200818973701
comparison of disk diffusion and agar dilution methods for erythromycin, ciprofloxacin, and tetracycline susceptibility testing of campylobacter coli and for tetracycline susceptibility testing of campylobacter jejuni subsp. jejuni.with disk diffusion, the following zone diameters are suggested to be resistant and susceptible breakpoints, respectively: for susceptibility testing of campylobacter coli, no inhibition zone and 15 mm or more for erythromycin, and 20 mm or less and 25 mm or more for ciprofloxacin, in the absence or presence of an inhibition zone around the nalidixic acid disk; and for susceptibility testing of c. coli and campylobacter jejuni, 20 mm or less and 26 mm or more for tetracycline.200818838597
rapid screening of salmonella enterica serovars enteritidis, hadar, heidelberg and typhimurium using a serologically-correlative allelotyping pcr targeting the o and h antigen alleles.classical salmonella serotyping is an expensive and time consuming process that requires implementing a battery of o and h antisera to detect 2,541 different salmonella enterica serovars. for these reasons, we developed a rapid multiplex polymerase chain reaction (pcr)-based typing scheme to screen for the prevalent s. enterica serovars enteritidis, hadar, heidelberg, and typhimurium.200818845003
genes and molecules of lactobacilli supporting probiotic action.lactobacilli have been crucial for the production of fermented products for centuries. they are also members of the mutualistic microbiota present in the human gastrointestinal and urogenital tract. recently, increasing attention has been given to their probiotic, health-promoting capacities. many human intervention studies demonstrating health effects have been published. however, as not all studies resulted in positive outcomes, scientific interest arose regarding the precise mechanisms of act ...200819052326
helicobacter pylori hopq outer membrane protein attenuates bacterial adherence to gastric epithelial cells.helicobacter pylori genomes contain about 30 hop genes that encode outer membrane proteins. helicobacter pylori hopq alleles exhibit a high level of genetic diversity, and two families of hopq alleles have been described. type i hopq alleles are found more commonly in cag-positive h. pylori strains from patients with peptic ulcer disease than in cag-negative strains from patients without ulcer disease. in this study, we mutated hopq in four h. pylori strains that each contained a type i hopq all ...200819065710
demographic determinants for campylobacter infection in england and wales: implications for future epidemiological studies.despite a significant public health burden the epidemiology of human campylobacter infection remains blurred. the identification of demographic determinants for campylobacter infection is therefore essential for identifying potential areas for intervention. demographic data from an active, population-based sentinel surveillance system for campylobacter infection (from 2000 until 2003, n=15 907) were compared with appropriate denominator data from the 2001 united kingdom census. incidence was hig ...200819000328
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
characterization of two putative cytochrome c peroxidases of campylobacter jejuni involved in promoting commensal colonization of poultry.campylobacter jejuni is a leading cause of bacterial gastroenteritis in humans throughout the world, but infection of animals, especially poultry, results in a commensal colonization of the intestines. we previously found that a mutant lacking doca, which encodes a putative cytochrome c peroxidase (ccp), demonstrates up to a 10(5)-fold reduction in colonization of the chick cecum compared to wild-type c. jejuni strain 81-176. predictions from genomic sequences identified cjj0382 as a second locu ...200818086814
characterization of two putative cytochrome c peroxidases of campylobacter jejuni involved in promoting commensal colonization of poultry.campylobacter jejuni is a leading cause of bacterial gastroenteritis in humans throughout the world, but infection of animals, especially poultry, results in a commensal colonization of the intestines. we previously found that a mutant lacking doca, which encodes a putative cytochrome c peroxidase (ccp), demonstrates up to a 10(5)-fold reduction in colonization of the chick cecum compared to wild-type c. jejuni strain 81-176. predictions from genomic sequences identified cjj0382 as a second locu ...200818086814
extended sequence typing of campylobacter spp., united kingdom.supplementing campylobacter spp. multilocus sequence typing with nucleotide sequence typing of 3 antigen genes increased the discriminatory index achieved from 0.975 to 0.992 among 620 clinical isolates from oxfordshire, united kingdom. this enhanced typing scheme enabled identification of clusters and retained data required for long-range epidemiologic comparisons of isolates.200818826829
molecular mechanisms involved in vascular interactions of the lyme disease pathogen in a living host.hematogenous dissemination is important for infection by many bacterial pathogens, but is poorly understood because of the inability to directly observe this process in living hosts at the single cell level. all disseminating pathogens must tether to the host endothelium despite significant shear forces caused by blood flow. however, the molecules that mediate tethering interactions have not been identified for any bacterial pathogen except e. coli, which tethers to host cells via a specialized ...200818833295
recombination-based in vivo expression technology identifies helicobacter pylori genes important for host colonization.here we undertook to identify colonization and gastric disease-promoting factors of the human gastric pathogen helicobacter pylori as genes that were induced in response to the stomach environment. using recombination-based in vivo expression technology (rivet), we identified six promoters induced in the host compared to laboratory conditions. three of these promoters, designated pivi10, pivi66, and pivi77, regulate genes that h. pylori may use to interact with other microbes or the host. pivi10 ...200818794279
monoclonal antibody binding to the major outer membrane protein of campylobacter coli.campylobacter species are major enteric pathogens causing diarrhea illness in humans and animals. immunological tests are needed for accurate and rapid identification of c. coli, in conjunction with the use of standard biochemical tests. we initiated the creation of monoclonal antibodies (mabs) using whole c. coli cells as antigen. four positive clones were identified, namely mab2g6, mab3b9, mab4a10 and mab5b9. dot-blot assay and elisa revealed that only mab2g6 did not cross react with c. jejuni ...200818796306
prevalence of thermotolerant campylobacter in pheasants (phasianus colchicus).the present study was undertaken with the aim to evaluate the prevalence of thermotolerant campylobacter spp. in living pheasants in italy. to achieve this goal, a total of 240 living pheasants, equally shared between female and male birds, were examined. thermotolerant campylobacter spp. was isolated in 104 out of 204 (43.3%) living pheasants analysed. campylobacter coli (100%) and campylobacter jejuni (13.5%) were identified by polymerase chain reaction. adult pheasants showed a significantly ...200818798025
identification of campylobacter jejuni proteins recognized by maternal antibodies of chickens.campylobacter jejuni is one of the leading bacterial causes of food-borne gastroenteritis. infection with c. jejuni is frequently acquired through the consumption of undercooked poultry or foods cross-contaminated with raw poultry. given the importance of poultry as a reservoir for campylobacter organisms, investigators have performed studies to understand the protective role of maternal antibodies in the ecology of campylobacter colonization of poultry. in a previous study, chicks with maternal ...200818805999
characterization of two campylobacter jejuni strains for use in volunteer experimental-infection studies.the development of vaccines against campylobacter jejuni would be facilitated by the ability to perform phase ii challenge studies. however, molecular mimicry of the lipooligosaccharide (los) of most c. jejuni strains with human gangliosides presents safety concerns about the development of guillain-barré syndrome. clinical isolates of c. jejuni that appeared to lack genes for the synthesis of ganglioside mimics were identified by dna probe analyses. two clinical isolates from southeast asia (st ...200818809665
longitudinal study of prevalence of campylobacter jejuni and campylobacter coli from turkeys and swine grown in close proximity.eastern north carolina is a major contributor to both turkey and swine production in the united states. in this region, turkeys and swine are frequently grown in close proximity and by common growers. to further characterize colonization of turkeys and swine with campylobacter in such a setting, we investigated the prevalence of thermophilic campylobacters in eight paired operations involving turkey farms in close proximity to finishing swine farms. all 15 surveyed flocks and 15 herds were campy ...200818810862
a large waterborne outbreak of campylobacteriosis in norway: the need to focus on distribution system safety.on 7 may 2007 the medical officer in røros (population 5600) reported 15 patients with gastroenteritis. three days later he estimated hundreds being ill. untreated tap water from a groundwater source was suspected as the vehicle and chlorination was started 11 may. campylobacter was isolated from patients' stool samples. we conducted an investigation to identify the source and describe the extent of the outbreak.200818816387
[evaluation of antigenic properties of campylobacter jejuni and campylobacter coli proteins in a western-immunoblot].campylobacter jejuni and campylobacter coli are the most common bacterial cause for acute diarrheal illnesses in developed countries. the aim of this study was to evaluate the antigenic properties of campylobacterjejuni and campylobacter coli proteins in western-blot assay. whole-cell components of campulobacter jejuni and campylobacter coli were separated by sodium dodecyl sulfate-polyacrylamide gel electroforesis. using this method we detected in all seven c. jejuni strains 21 peptides migrati ...200818819448
development of a loop-mediated isothermal amplification assay for sensitive and rapid detection of vibrio parahaemolyticus.vibrio parahaemolyticus is a marine seafood-borne pathogen causing gastrointestinal disorders in humans. thermostable direct hemolysin (tdh) and tdh-related hemolysin (trh) are known as major virulence determinants of v. parahaemolyticus. most v. parahaemolyticus isolates from the environment do not produce tdh or trh. total v. parahaemolyticus has been used as an indicator for control of seafood contamination toward prevention of infection. detection of total v. parahaemolyticus using conventio ...200818823567
occurrence and characterization of campylobacter in the brazilian production and processing of broilers.twenty-two commercial broiler flocks and their carcasses, totaling 546 samples (450 collected from a poultry farm and 96 from a slaughterhouse), were surveyed for the presence of campylobacter. the positive results for campylobacter among the analyzed samples were homogeneous, yielding 81.8% for cecal droppings, 80.9% for feces, and 80.4% for cloacal swabs. pre-enrichment and direct plating showed that 77.85% and 81.8% of cloacal swabs, respectively, were positive for campylobacter compared to 9 ...200819166063
evidence of cross-contamination by campylobacter spp. of broiler carcasses using genetic characterization of isolates.campylobacter is recognized as one of the leading cause of gastroenteritis worldwide, and is frequently isolated from the small intestines and ceca microflora of chickens. twenty-one out of 81 campylobacter-positive poultry flocks were selected to evaluate the genetic diversity of campylobacter isolates and to study the distribution of genotypes among flocks. campylobacter isolates recovered from chicken carcasses and ceca were analyzed by pulsed-field gel electrophoresis (pfge). little diversit ...200819086371
[annual changes in antimicrobial susceptibility of campylobacter jejuni and campylobacter coli isolated from acute diarrheic patients].two hundred thirty-one campylobacter were isolated from acute diarrheic patients between january 2001 and december 2005. we evaluated annual changes in identified species of campylobacter and their susceptibilities against antibiotics. campylobacter jejuni (219 strains; 94.8%) and campylobacter coli (12 strains; 5.2%) were identified to the species. susceptibilities to four antimicrobial agents, minocycline (mino), levofloxacin (lvfx), erythromycin (em) and clindamycin (cldm) were examined. the ...200819086420
trends of norfloxacin and erythromycin resistance of campylobacter jejuni/campylobacter coli isolates recovered from international travelers, 1994 to 2006.campylobacter sp. is a major cause of bacterial enterocolitis and travelers' diarrhea. empiric treatment regimens include fluoroquinolones and macrolides.200819090796
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
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
[evaluation of usefulness of commercial recomwell campylobacter enzyme--linked immunosorbent assays for routine serodiagnosis of campylobacter jejuni and campylobacter coli infections].the commercially available enzyme-linked immunosorbent assays (elisa recomwell campylobacter) from mikrogen was evaluated for the diagnosis of campylobacter jejuni and campylobacter coli infections. serum samples from 20 healthy controls, 44 persons with symptoms of primary campylobacter infection and 24 serum samples from patients with yersinia enterocolitica or salmonella infections were tested. this elisa assay detects iga and igg antibodies against three recombinant antigens of the campyloba ...200819382600
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
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
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
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
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
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
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
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
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
[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
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
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
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
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