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a genomic island defines subspecies-specific virulence features of the host-adapted pathogen campylobacter fetus subsp. venerealis.the pathogen campylobacter fetus comprises two subspecies, c. fetus subsp. fetus and c. fetus subsp. venerealis. although these taxa are highly related on the genome level, they are adapted to distinct hosts and tissues. c. fetus subsp. fetus infects a diversity of hosts, including humans, and colonizes the gastrointestinal tract. in contrast, c. fetus subsp. venerealis is largely restricted to the bovine genital tract, causing epidemic abortion in these animals. in light of their close genetic ...201019897645
demonstration of persistent strains of campylobacter jejuni within broiler farms over a 1-year period in lithuania.the aim of the study was to investigate the flock prevalence of campylobacter jejuni and campylobacter coli in broiler farms in lithuania and to identify possible persistent strains of camp. jejuni using amplified fragment length polymorphism (aflp) typing method.201019709341
occurrence of salmonella, campylobacter, yersinia enterocolitica, escherichia coli o157 and listeria monocytogenes in swine.the objective of this study was to investigate the occurrence of major bacterial foodborne pathogens in swine. in total, 359 samples from manure storage tanks (91) and fresh pooled faeces (268) obtained from finisher (110), sows (78) and weanlings (80) were collected and tested. campylobacter, salmonella, yersinia enterocolitica, escherichia coli o157 and listeria monocytogenes were isolated from 36.5%, 31.5%, 5.8%, 3.3% and 3.3% of samples respectively. all e. coli o157 isolates found on 10 far ...201019638163
comparison between the biofilm initiation of campylobacter jejuni and campylobacter coli strains to an inert surface using biofilm ring test.the adhesion to an inert surface (the first step of biofilm formation) of the two main pathogenic campylobacter species, campylobacter jejuni and campylobacter coli, isolated from diverse origins, was compared.201019796124
inaccuracy of routine susceptibility tests for detection of erythromycin resistance of campylobacter jejuni and campylobacter coli.in the netherlands, both an increase in and regional differences in erythromycin resistance of campylobacter jejuni and campylobacter coli have been reported. to determine the accuracy of routine tests for erythromycin resistance, 48 erythromycin-resistant isolates from various laboratories that participate in the dutch surveillance of campylobacter infections were reinvestigated. initial susceptibility testing for erythromycin had been performed by disk diffusion in six and mic-based methods in ...201019438640
dna identification and characterization of campylobacter jejuni and campylobacter coli isolated from caecal samples of chickens in grenada.to speciate campylobacter strains from the caeca of chickens in grenada using pcr and to evaluate dna-based typing methods for the characterization of these isolates.201019735321
prevalence of virulence-associated genes and cytolethal distending toxin production in campylobacter spp. isolated in italy.the prevalence of virulence and cytolethal distending toxin (cdt) genes and the cytotoxic activity in vero and hep-2 cells was estimated in 29 campylobacter jejuni and 36 campylobacter coli from foods, animals and humans isolates. all c. jejuni showed flaa, cadf, cdta, cdtb, cdtc and cdt cluster genes fragments, except for ceue (86.2%) and cdt genes (93.1%). amongst c. coli strains, a lower prevalence of ceue gene (83.3%) was detected than that for cdta, cdtb, cdtc genes (97.2%), cdt gene cluste ...201019195703
methods for determining disease burden and calibrating national surveillance data in the united kingdom: the second study of infectious intestinal disease in the community (iid2 study).infectious intestinal disease (iid), usually presenting as diarrhoea and vomiting, is frequently preventable. though often mild and self-limiting, its commonness makes iid an important public health problem. in the mid 1990s around 1 in 5 people in england suffered from iid a year, costing around pound0.75 billion. no routine information source describes the uk's current community burden of iid. we present here the methods for a study to determine rates and aetiology of iid in the community, pre ...201020444246
tir domain-containing adaptor sarm is a late addition to the ongoing microbe-host dialog.toll/interleukin-1 receptor (tir) domain-containing proteins play important roles in defense against pathogens in both animals and plants, connecting the immunity signaling pathways via a chain of specific protein-protein interactions. among them is sarm, the only tir domain-containing adaptor that can negatively regulate tlr signaling. by extensive phylogenetic analysis, we show here that sarm is closely related to bacterial proteins with tir domains, suggesting that this family has a different ...201021110998
risk assessment of growth hormones and antimicrobial residues in meat.growth promoters including hormonal substances and antibiotics are used legally and illegally in food producing animals for the growth promotion of livestock animals. hormonal substances still under debate in terms of their human health impacts are estradiol-17β, progesterone, testosterone, zeranol, trenbolone, and melengestrol acetate (mga) . many of the risk assessment results of natural steroid hormones have presented negligible impacts when they are used under good veterinary practices. for ...201024278538
molecular characterization of the 16s rrna gene of helicobacter fennelliae isolated from stools and blood cultures from paediatric patients in south africa.forty strains of h. fennelliae collected from paediatric blood and stool samples over an 18 year period at a children's hospital in cape town, south africa, were amplified by pcr of the 16s rrna. two distinct genotypes of h. fennelliae were identified based on the phylogenetic analysis. this was confirmed by sequencing a portion of the beta subunit of the rna polymerase (rpob) gene. all isolates from south africa clustered with a proposed novel helicobacter strain (accession number af237612) iso ...201022567323
molecular characterization of the 16s rrna gene of helicobacter fennelliae isolated from stools and blood cultures from paediatric patients in south africa.forty strains of h. fennelliae collected from paediatric blood and stool samples over an 18 year period at a children's hospital in cape town, south africa, were amplified by pcr of the 16s rrna. two distinct genotypes of h. fennelliae were identified based on the phylogenetic analysis. this was confirmed by sequencing a portion of the beta subunit of the rna polymerase (rpob) gene. all isolates from south africa clustered with a proposed novel helicobacter strain (accession number af237612) iso ...201022567323
tir domain-containing adaptor sarm is a late addition to the ongoing microbe-host dialog.toll/interleukin-1 receptor (tir) domain-containing proteins play important roles in defense against pathogens in both animals and plants, connecting the immunity signaling pathways via a chain of specific protein-protein interactions. among them is sarm, the only tir domain-containing adaptor that can negatively regulate tlr signaling. by extensive phylogenetic analysis, we show here that sarm is closely related to bacterial proteins with tir domains, suggesting that this family has a different ...201021110998
flagellin as an adjuvant: cellular mechanisms and potential.flagellin is a potent activator of a broad range of cell types involved in innate and adaptive immunity. an increasing number of studies have demonstrated the effectiveness of flagellin as an adjuvant, as well as its ability to promote cytokine production by a range of innate cell types, trigger a generalized recruitment of t and b lymphocytes to secondary lymphoid sites, and activate tlr5(+)cd11c(+) cells and t lymphocytes in a manner that is distinct from cognate ag recognition. the plasticity ...201021048152
microbial diagnostic microarray for food- and water-borne pathogens.a microbial diagnostic microarray for the detection of the most relevant bacterial food- and water-borne pathogens and indicator organisms was developed and thoroughly validated. the microarray platform based on sequence-specific end labelling of oligonucleotides and the pyhylogenetically robust gyrb marker gene allowed a highly specific (resolution on genus/species level) and sensitive (0.1% relative and 10(4) cfu absolute detection sensitivity) detection of the target pathogens. validation was ...201021255342
the era of molecular and other non-culture-based methods in diagnosis of sepsis.sepsis, a leading cause of morbidity and mortality throughout the world, is a clinical syndrome with signs and symptoms relating to an infectious event and the consequent important inflammatory response. from a clinical point of view, sepsis is a continuous process ranging from systemic inflammatory response syndrome (sirs) to multiple-organ-dysfunction syndrome (mods). blood cultures are the current "gold standard" for diagnosis, and they are based on the detection of viable microorganisms pres ...201020065332
abc transporters involved in export of cell surface glycoconjugates.complex glycoconjugates play critical roles in the biology of microorganisms. despite the remarkable diversity in glycan structures and the bacteria that produce them, conserved themes are evident in the biosynthesis-export pathways. one of the primary pathways involves representatives of the atp-binding cassette (abc) transporter superfamily. these proteins are responsible for the export of a wide variety of cell surface oligo- and polysaccharides in both gram-positive and gram-negative bacteri ...201020805402
diversity and impact of prokaryotic toxins on aquatic environments: a review.microorganisms are ubiquitous in all habitats and are recognized by their metabolic versatility and ability to produce many bioactive compounds, including toxins. some of the most common toxins present in water are produced by several cyanobacterial species. as a result, their blooms create major threats to animal and human health, tourism, recreation and aquaculture. quite a few cyanobacterial toxins have been described, including hepatotoxins, neurotoxins, cytotoxins and dermatotoxins. these t ...201022069558
pulsed field gel electrophoresis typing of human and retail foodstuff campylobacters: an irish perspective.campylobacter enteritis is a zoonosis, an infectious disease transmissible under normal conditions from vertebrate animals to man, presenting a major global public health burden. in this study, pulsed field gel electrophoresis (pfge) was employed to identify common genotypes in a collection of 600 campylobacter isolates in order to investigate if profiles obtained from retail samples of foodstuffs matched genotypes causing illness in the community in ireland. the campylobacters were isolated fro ...201021356447
adherence, invasion, toxigenic, and chemotactic properties of mexican campylobacter strains.to determine the virulence factors of mexican wild-type strains of campylobacter jejuni and campylobacter coli, 31 wild-type strains were isolated from food and from humans. the production of cytolethal distending toxin and the adherence and invasion capabilities of these strains were assayed in vero cells. hard agar plugs with repellents and attractants were used to examine chemotaxis. mueller-hinton agar with supplements was used for motility analysis and to measure hemolytic activity. nine st ...201021219724
successful treatment of cryptosporidiosis in 2 common marmosets (callithrix jacchus) by using paromomycin.two pair-housed, 1-y-old common marmosets (callithrix jacchus) had intermittent loose feces and weight loss for approximately 2 mo. cryptosporidum parvum was identified by elisa in the feces of both animals. cbc and blood chemistry values, including liver enzymes, were within normal range. both marmosets were treated with the antibiotic paromomycin (15 mg/kg po) twice daily for 28 d. resolution of clinical signs coincided with treatment. three follow-up samples, taken 2 wk apart after treatment ...201021205457
simultaneous screening of 24 target genes of foodborne pathogens in 35 foodborne outbreaks using multiplex real-time sybr green pcr analysis.a set of 8 multiplex real-time sybr green pcr (sg-pcr) assays including 3 target primers and an internal amplification control (iac) primer was simultaneously evaluated in 3 h or less with regard to detection of 24 target genes of 23 foodborne pathogens in 7 stool specimens of foodborne outbreak using a 96-well reaction plate. this assay, combined with dna extraction (qiaamp dna stool mini kit), offered detection of greater than 10(3)-10(4) foodborne pathogens per g in stool specimens. the produ ...201020936159
solexaqa: at-a-glance quality assessment of illumina second-generation sequencing data.illumina's second-generation sequencing platform is playing an increasingly prominent role in modern dna and rna sequencing efforts. however, rapid, simple, standardized and independent measures of run quality are currently lacking, as are tools to process sequences for use in downstream applications based on read-level quality data.201020875133
microbial efflux pump inhibition: tactics and strategies.traditional antimicrobials are increasingly suffering from the emergence of multidrug resistance among pathogenic microorganisms. to overcome these deficiencies, a range of novel approaches to control microbial infections are under investigation as potential alternative treatments. multidrug efflux is a key target of these efforts. efflux mechanisms are broadly recognized as major components of resistance to many classes of chemotherapeutic agents as well as antimicrobials. efflux occurs due to ...201121470111
a comparison between hippurate hydrolysis and multiplex pcr for differentiating campylobacter coli and campylobacter jejuni.species identification is important for epidemiological, clinical and treatment purposes. the aim of this study was to find out whether hippurate hydrolysis is a reliable test for differentiating between campylobacter coli and campylobacter jejuni. to achieve this, hippurate hydrolysis test was compared with multiplex polymerase chain reaction (mpcr) for their ability to speciate c. coli and c. jejuni. eighteen campylobacter strains from poultry samples were used for this study. the results from ...201124575212
evolution of the oligopeptide transporter family.the oligopeptide transporter (opt) family of peptide and iron-siderophore transporters includes members from both prokaryotes and eukaryotes but with restricted distribution in the latter domain. eukaryotic members were found only in fungi and plants with a single slime mold homologue clustering with the fungal proteins. all functionally characterized eukaryotic peptide transporters segregate from the known iron-siderophore transporters on a phylogenetic tree. prokaryotic members are widespread, ...201121347612
comparative genotypic and pathogenic examination of campylobacter concisus isolates from diarrheic and non-diarrheic humans.campylobacter concisus is an emerging enteric pathogen, yet it is commonly isolated from feces and the oral cavities of healthy individuals. this genetically complex species is comprised of several distinct genomospecies which may vary in pathogenic potential.201121406111
Development of a rapid and sensitive method combining a cellulose ester microfilter and a real-time qPCR assay to detect Campylobacter jejuni and Campylobacter coli in 20 liters of drinking water or low turbidity waters.Investigation of Campylobacter jejuni and Campylobacter coli in samples of drinking water suspected of being at the origin of outbreak very often leads to negative results. One of the reasons for this failure is the small volume of water typically used for detecting these pathogens (10 to 1000 mL). Efficiency of three microfilters and different elution procedures were determined using real-time qPCR to propose a procedure allowing detection of Campylobacter in 20 L drinking water or low turbidit ...201122138985
closely related campylobacter jejuni strains from different sources reveal a generalist rather than a specialist lifestyle.abstract: background: campylobacter jejuni and campylobacter coli are human intestinal pathogens of global importance. zoonotic transmission from livestock animals or animal-derived food is the likely cause for most of these infections. however, little is known about their general and host-specific mechanisms of colonization, or virulence and pathogenicity factors. in certain hosts, campylobacter species colonize persistently and do not cause disease, while they cause acute intestinal disease i ...201122122991
helicobacter pylori relies primarily on the purine salvage pathway for purine nucleotide biosynthesis.helicobacter pylori is a chronic colonizer of the gastric epithelium and plays a major role in the development of gastritis, peptic ulcer disease, and gastric cancer. in its co-evolution with humans, a streamlining of the h. pylori genome has resulted in a significant reduction in metabolic pathways, one being purine nucleotide biosynthesis. bioinformatic analysis revealed that h. pylori lacks the enzymatic machinery for de novo production of inosine monophosphate (imp), the first purine nucleot ...201122194455
fate of pathogens in a simulated bioreduction system for livestock carcasses.the eu animal by-products regulations generated the need for novel methods of storage and disposal of dead livestock. bioreduction prior to rendering or incineration has been proposed as a practical and potentially cost-effective method; however, its biosecurity characteristics need to be elucidated. to address this, salmonella enterica (serovars senftenberg and poona), enterococcus faecalis, campylobacter jejuni, campylobacter coli and a lux-marked strain of escherichia coli o157 were inoculate ...201122119516
prevalence and antimicrobial susceptibility of campylobacter in broiler flocks in japan.campylobacter was isolated from 67 (47.2%) of 142 broiler flocks between september 2009 and february 2010. the prevalence of campylobacter in broiler flocks was significantly lower during january and february than it was from september to december. campylobacter colonization was more common in flocks that were not provided with a disinfected water supply, which was consistent with the findings of a previous study. the prevalence of antimicrobial drug-resistant campylobacter spp. was investigated ...201122103704
A Nationwide Study of Campylobacter jejuni and Campylobacter coli bacteremia in Finland over a 10-year period, 1998-2007, with special reference to clinical characteristics and antimicrobial susceptibility.Campylobacter bacteremia is an uncommon condition, usually diagnosed in elderly and immunocompromised patients.201121921217
genetic organisation, mobility and predicted functions of genes on integrated, mobile genetic elements in sequenced strains of clostridium difficile.clostridium difficile is the leading cause of hospital-associated diarrhoea in the us and europe. recently the incidence of c. difficile-associated disease has risen dramatically and concomitantly with the emergence of 'hypervirulent' strains associated with more severe disease and increased mortality. c. difficile contains numerous mobile genetic elements, resulting in the potential for a highly plastic genome. in the first sequenced strain, 630, there is one proven conjugative transposon (ctn) ...201121876735
prevalence of campylobacter species in adult crohn's disease and the preferential colonization sites of campylobacter species in the human intestine.crohn's disease (cd) and ulcerative colitis (uc) are the two major forms of inflammatory bowel disease (ibd). a high prevalence of campylobacter concisus was previously detected in paediatric cd and adult uc. currently, the prevalence of c. concisus in adult cd and the preferential colonization sites of campylobacter species in the human intestine are unknown. in this study, we examined the prevalence of campylobacter species in biopsies collected from multiple anatomic sites of adult patients w ...201121966525
helicobacter pylori exploits a unique repertoire of type iv secretion system components for pilus assembly at the bacteria-host cell interface.colonization of the human stomach by helicobacter pylori is an important risk factor for development of gastric cancer. the h. pylori cag pathogenicity island (cag pai) encodes components of a type iv secretion system (t4ss) that translocates the bacterial oncoprotein caga into gastric epithelial cells, and cagl is a specialized component of the cag t4ss that binds the host receptor α5β1 integrin. here, we utilized a mass spectrometry-based approach to reveal co-purification of cagl, cagi (anoth ...201121909278
does human bocavirus infection depend on helper viruses? a challenging case report.a case of severe diarrhoea associated with synergistic human bocavirus type 1 (hbov) and human herpes virus type 6 (hhv6) is reported. the case supports the hypotheses that hbov infection under clinical conditions may depend on helper viruses, or that hbov replicates by a mechanism that is atypical for parvoviruses, or that hbov infection can be specifically treated with cidofovir.201121871135
a comprehensive evaluation of colonic mucosal isolates of sutterella wadsworthensis from inflammatory bowel disease.inflammatory bowel disease (ibd) arises in genetically susceptible individuals as a result of an unidentified environmental trigger, possibly a hitherto unknown bacterial pathogen. twenty-six clinical isolates of sutterella wadsworthensis were obtained from 134 adults and 61 pediatric patients undergoing colonoscopy, of whom 69 and 29 respectively had ibd. s. wadsworthensis was initially more frequently isolated from ibd subjects, hence this comprehensive study was undertaken to elucidate its ro ...201122073125
Improvement of Modified Charcoal-Cefoperazone-Deoxycholate Agar by Supplementation with a High Concentration of Polymyxin B for the Detection of Campylobacter jejuni and C. coli in Chicken Carcass Rinse.Modified charcoal-cefoperazone-deoxycholate agar (mCCDA) was improved by supplementation with a high concentration of polymyxin B. The ability of the supplemented medium to isolate Campylobacter jejuni and C. coli from chicken carcass rinse was compared to that of Campy-Cefex agar and mCCDA. Modification of mCCDA with increased polymyxin B yielded significantly (p < 0.05) better isolation rate and selectivity than those achieved on using Campy-Cefex agar and mCCDA.201122210208
a model for the effect of homologous recombination on microbial diversification.the effect of homologous recombination (hr) on the evolution of microbial genomes remains contentious as competing hypotheses seek to explain the evolutionary dynamics of microbial species. evidence for hr between microbial genomes is widespread, and this process has been proposed to act as a cohesive force that can constrain the diversification of microbial lineages. we seek to characterize the evolutionary dynamics of sympatric populations to explore the impact of hr on microbial speciation. w ...201122071790
fate and survival of campylobacter coli in swine manure at various temperatures.campylobacter coli is the most common campylobacter species found in pig (95%), but the ability of this bacterium to survive in swine manure as well as the potential for causing human illness are poorly understood. we present here laboratory-scale experiments to investigate the effect of temperature on the survival of c. coli in spiked swine manure samples at temperatures from 4 to 52°c. the survival of c. coli during storage for 30 days was studied by three different methods: bacterial culture ...201122207868
Comparative Genomics of Helicobacter pylori and the human-derived Helicobacter bizzozeronii CIII-1 strain reveal the molecular basis of the zoonotic nature of non-pylori gastric Helicobacter infections in humans.ABSTRACT:201122039924
Genome and proteome of Campylobacter jejuni bacteriophage NCTC 12673.Campylobacter jejuni continues to be the leading cause of bacterial food-borne illness worldwide, so improvements to current methods used for bacterial detection and disease prevention are needed. We describe here the genome and proteome of C. jejuni bacteriophage NCTC 12673 and the exploitation of its receptor-binding protein for specific bacterial detection. Remarkably, the 135-kb Myoviridae genome of NCTC 12673 differs greatly from any other proteobacterial phage genome described (including C ...201121965409
campylobacter populations in wild and domesticated mallard ducks (anas platyrhynchos).identifying the campylobacter genotypes that colonize farmed and wild ducks will help to assess the proportion of human disease that is potentially attributable to the consumption of duck meat and environmental exposure to duck faeces. comparison of temporally and geographically matched farmed and wild ducks showed that they had different campylobacter populations in terms of: (i) prevalence, (ii) campylobacter species and (iii) diversity of genotypes. furthermore, 92.4% of campylobacter isolate ...201122164198
pathogenic potential of campylobacter ureolyticus.the recent detection and isolation of the aflagellate campylobacter ureolyticus (previously known as bacteroides ureolyticus) from intestinal biopsy specimens and fecal samples of children with newly diagnosed crohn's disease led us to investigate the pathogenic potential of this bacterium. adherence and gentamicin protection assays were employed to quantify the levels of adherence to and invasion into host cells. c. ureolyticus unswcd was able to adhere to the caco-2 intestinal epithelial cell ...201122124656
effects of polyphosphate additives on the ph of processed chicken exudates and the survival of campylobacter.campylobacter spp. are nutritionally fastidious organisms that are sensitive to normal atmospheric oxygen levels and lack homologues of common cold shock genes. at first glance, these bacteria seem ill equipped to persist within food products under processing and storage conditions; however, they survive in numbers sufficient to cause the largest number of foodborne bacterial disease annually. a mechanism proposed to play a role in campylobacter survival is the addition of polyphosphate-contain ...201122004823
analysis of caga in helicobacter pylori strains from colombian populations with contrasting gastric cancer risk reveals a biomarker for disease severity.helicobacter pylori infection is a risk factor for the development of gastric cancer, and the bacterial oncoprotein caga contributes to gastric carcinogenesis.201121859954
identification of lactobacilli residing in chicken ceca with antagonism against campylobacter.bacteriocins produced by lactobacillus salivarius have been recently recognized as a natural means to control campylobacter and salmonella in live poultry. this finding is of relevance since campylobacter jejuni and campylobacter coli are the predominant species isolated from poultry that are associated with human campylobacteriosis. in the present work, lactic acid bacteria (lab) isolated from the cecum of twenty tunisian chickens were identified and those isolates with antagonism against campy ...201122069154
Prevalence and antimicrobial susceptibility of major foodborne pathogens in imported seafood.Seafood is a leading commodity implicated in foodborne disease outbreaks in the United States. Seafood importation rose dramatically in the past 3 decades and now contributes to more than 80% of the total U.S. seafood supply. However, limited data are available on the microbiological safety of imported seafood. In this study, we obtained a total of 171 salmon, shrimp, and tilapia samples imported from 12 countries in three retail stores in Baton Rouge, LA. The total microbial population and the ...201121902913
Ribosomal mutations as the main cause of macrolide resistance in Campylobacter jejuni and Campylobacter coli.The aim of this study was to examine macrolide resistance mutations in Campylobacter species. In 76 strains studied, point mutation A to G at position 2059 of the 23S rRNA gene was detected in 30 of the 33 erythromycin-resistant strains. An amino acid insertion in the ribosomal protein L22 was found in one resistant strain without a 23S rRNA mutation. The A2059G mutation is the main cause of macrolide resistance in Campylobacter species.201121911571
[antimicrobial sensitivity of hippurate-negative campylobacter and helicobacter pullorum strains isolated from patients with diarrhea].c. jejuni as well as some hippurate-negative campylobacter species and related diarrheagenic organisms, are the leading cause of gastroenteritis in our environment all throughout the year. the aim of the present study was to determine the sensitivity of hippurate-negative campylobacter and helicobacter pullorum strains isolated from the stools of patients with diarrhea. we tested 39 campylobacter coli, two c. lari and five helicobacter pullorum strains identified by mass spectrometry analysis. t ...201122173192
impaired fitness and transmission of macrolide-resistant campylobacter jejuni in its natural host.campylobacter jejuni is a major zoonotic pathogen transmitted to humans via the food chain and is prevalent in chickens, a natural reservoir for this pathogenic organism. due to the importance of macrolide antibiotics in clinical therapy of human campylobacteriosis, development of macrolide resistance in campylobacter has become a concern for public health. to facilitate the control of macrolide-resistant campylobacter, it is necessary to understand if macrolide resistance affects the fitness an ...201122183170
emerging dynamics of human campylobacteriosis in southern ireland.infections with campylobacter spp. pose a significant health burden worldwide. the significance of campylobacter jejuni/campylobacter coli infection is well appreciated but the contribution of non-c. jejuni/c. coli spp. to human gastroenteritis is largely unknown. in this study, we employed a two-tiered molecular study on 7194 patient faecal samples received by the microbiology department in cork university hospital during 2009. the first step, using entericbio(®) (serosep), a multiplex pcr syst ...201122077228
pulsed-field gel electrophoresis analysis of more than one clinical isolate of campylobacter spp. from each of 49 patients in new zealand.pulsed-field gel electrophoresis (pfge) analysis demonstrated that while 76% of patients had only one genotype of campylobacter, 10% carried two different but related genotypes (dice coefficients > 0.78), and 14% carried at least two unrelated genotypes (dice coefficients < 0.65). this supports the clustering of campylobacter isolates with similar pfge patterns, highlights the need to analyze multiple isolates from both sources and patients, and confirms that caution should be exercised before e ...201122116155
campylobacter spp. as a foodborne pathogen: a review.campylobacter is well recognized as the leading cause of bacterial foodborne diarrheal disease worldwide. symptoms can range from mild to serious infections of the children and the elderly and permanent neurological symptoms. the organism is a cytochrome oxidase positive, microaerophilic, curved gram-negative rod exhibiting corkscrew motility and is carried in the intestine of many wild and domestic animals, particularly avian species including poultry. intestinal colonization results in healthy ...201121991264
extracts of edible and medicinal plants in inhibition of growth, adherence, and cytotoxin production of campylobacter jejuni and campylobacter coli.campylobacter spp. is recognized as one of the most common cause of food-borne bacterial gastroenteritis in humans. campylobacter infection causes campylobacteriosis, which can range from asymptomatic to dysentery-type illnesses with severe complications, such as guillian-barre syndrome. epidemiological studies have revealed that consumption of poultry products is an important risk factor of this disease. adherence and cytotoxic activity of the bacteria to host mucosal surfaces have been propose ...201122417513
genotypes and antibiotic resistance of campylobacter coli in fattening pigs.campylobacter coli is a food-borne zoonotic pathogen causing human gastroenteritis worldwide. the organism is a commensal in the intestine of many food production animals including fattening pigs. the role of the pig as a potential reservoir for c. coli affecting human either directly or via poultry has hardly been investigated and genetic characterization of porcine strains is needed to address this question. for this aim multilocus sequence typing (mlst) and flab typing was applied to 256 c. c ...201121899961
evaluation of novel agars for the enumeration of campylobacter spp. in poultry retail samples.the purpose of this study was to examine the performance of novel agars for the identification and enumeration of campylobacter species. the analytical sensitivity and specificity of campylobacter selective agar (casa), brilliance campycount agar (bcca) and campyfoodidagar (cfa) for 84 campylobacter spp. isolates and 50 non-campylobacter spp. isolates from 37 distinct genera were of 100% sensitivity, with a 98% specificity for bcca and cfa, and a 100% specificity for casa. the application of the ...201122226753
campylobacter jejuni infection and its virulence associated genes among children with moderate to severe diarrhea attended at emergency rooms in northeastern brazil.campylobacter is an important cause of foodborne gastroenteritis. we determined the occurrence of campylobacter sp. - using culture-based methods - and c. jejuni, c. coli and some virulence associated genes (vag) - using pcr - among children aged ≤ 14 years attended at emergency rooms in northeastern brazil because of diarrhea. genomic dna was extracted directly from stool samples collected from 366 children. a survey form regarding clinical parameters was applied to caretakers. c. jejuni was de ...201122174372
the zinc-ribbon domain of helicobacter pylori hp0958: requirement for rpon accumulation and possible roles of homologs in other bacteria.helicobacter pylori hp0958 protein (flgz) prevents the rapid turnover of rpon (σ(54)), a transcription factor required for expression of several flagellar genes in h. pylori. flgz possesses a zinc-ribbon domain (duf164) that contains two conserved cxxc motifs which coordinate a zinc ion and is thought to interact with nucleic acids or proteins. two conserved cysteine residues in flgz (cys-202 and cys-223) were replaced with serine to assess their significance in flgz function. after confirming t ...201122408721
welcome to microbial informatics and experimentation. 201122587655
identification of genes involved in the glycosylation of modified viosamine of flagellins in pseudomonas syringae by mass spectrometry.previously we revealed that flagellin proteins in pseudomonas syringae pv. tabaci 6605 (pta 6605) were glycosylated with a trisaccharide, modified viosamine (mvio)-rhamnose-rhamnose and that glycosylation was required for virulence. we further identified some glycosylation-related genes, including vioa, viob, viot, fgt1, and fgt2. in this study, we newly identified vior and viom in a so-called viosamine island as biosynthetic genes for glycosylation of mvio in pta 6605 by the mass spectrometry ( ...201124710292
human isolates of cronobacter sakazakii bind efficiently to intestinal epithelial cells in vitro to induce monolayer permeability and apoptosis.cronobacter sakazakii (cs) is an emerging opportunistic pathogen that causes life-threatening infections in infants. this pathogen has been implicated in the outbreaks of necrotizing enterocolitis (nec) with associated rates of high mortality and morbidity. in this study, we compared the abilities of cs strains isolated from human and environmental sources to bind to intestinal epithelial cells and trigger apoptosis.201122221600
human isolates of cronobacter sakazakii bind efficiently to intestinal epithelial cells in vitro to induce monolayer permeability and apoptosis.cronobacter sakazakii (cs) is an emerging opportunistic pathogen that causes life-threatening infections in infants. this pathogen has been implicated in the outbreaks of necrotizing enterocolitis (nec) with associated rates of high mortality and morbidity. in this study, we compared the abilities of cs strains isolated from human and environmental sources to bind to intestinal epithelial cells and trigger apoptosis.201122221600
defining the causes of diarrhea: novel approaches.diarrheal disease causes substantial morbidity and mortality worldwide; however, defining the microbiologic causes are challenging due to the large number of potential enteropathogens that require testing, insensitivity of existing conventional methods, the frequent occurrence of mixed infections, and high rates of background carriage in many communities.201121844805
inadequacies of minimum spanning trees in molecular epidemiology.minimum spanning trees (msts) are frequently used in molecular epidemiology research to estimate relationships among individual strains or isolates. nevertheless, there are significant caveats to mst algorithms that have been largely ignored in molecular epidemiology studies and that have the potential to confound or alter the interpretation of the results of those analyses. specifically, (i) presenting a single, arbitrarily selected mst illustrates only one of potentially many equally optimal s ...201121849692
cytolethal distending toxin: a conserved bacterial genotoxin that blocks cell cycle progression, leading to apoptosis of a broad range of mammalian cell lineages.cytolethal distending toxin (cdt) is a heterotrimeric ab-type genotoxin produced by several clinically important gram-negative mucocutaneous bacterial pathogens. irrespective of the bacterial species of origin, cdt causes characteristic and irreversible cell cycle arrest and apoptosis in a broad range of cultured mammalian cell lineages. the active subunit cdtb has structural homology with the phosphodiesterase family of enzymes including mammalian dnase i, and alone is necessary and sufficient ...201121565933
carry-over of thermophilic campylobacter spp. between sequential and adjacent poultry flocks.nineteen flocks of four poultry species were monitored at a veterinary field station to investigate the distribution and spread of campylobacter genotypes between sequential and adjacent flocks. caecal and liver samples were obtained at frequent intervals from birds of all flocks and examined for campylobacter. amplified fragment length polymorphism (aflp) analysis was performed to genotype campylobacter isolates. of the 1643 caecal and liver samples investigated, 452 (27.5%) caecal samples and ...201120619560
survival of escherichia coli, enterococci, and campylobacter spp. in sheep feces on pastures.the survival of enteric bacteria in 10 freshly collected sheep fecal samples on pastures was measured in each of four seasons. ten freshly collected feces were placed on pasture, and concentrations of escherichia coli, enterococci, and campylobacter spp. were monitored until exhaustion of the fecal samples. in all four seasons, there was an increase in enterococcal concentrations by up to 3 orders of magnitude, with peak concentrations recorded between 11 and 28 days after deposition. e. coli co ...201121239546
persistence of free-living protozoan communities across rearing cycles in commercial poultry houses.the introduction and survival of zoonotic bacterial pathogens in poultry farming have been linked to bacterial association with free-living protozoa. to date, however, no information is available on the persistence of protozoan communities in these environments across consecutive rearing cycles and how it is affected by farm- and habitat-specific characteristics and management strategies. we therefore investigated the spatial and temporal dynamics of free-living protozoa in three habitats (pipel ...201121239551
detection, isolation, and characterization of helicobacter species from the gastrointestinal tract of the brushtail possum.the presence of helicobacter species in australian marsupials was examined systematically using microscopy, culture, and pcr in different regions of the gastrointestinal tract (git) and in the liver of brushtail possums (btps) (trichosurus vulpecula), a common australian marsupial that feeds on eucalyptus leaves. the spatial distribution of helicobacter species in the git sections also was examined microscopically in silver-stained sections and by fluorescent in situ hybridization (fish) using a ...201121216901
arcobacter population dynamics in pigs on farrow-to-finish farms.healthy pigs are an important reservoir for the emerging human pathogen arcobacter which can result in contamination of porcine carcasses and pork and the spread of arcobacters into the environment. up to now, the excretion of arcobacters by pigs has been studied, but information about the transmission routes in fattening pigs is lacking. the present study aimed to elucidate the arcobacter population dynamics in pigs during the fattening period on four farrow-to-finish farms. on each farm, 30 cl ...201121216902
occurrences of thermophilic campylobacter in pigs slaughtered at morogoro slaughter slabs, tanzania.occurrences of thermophlic campylobacter in pigs and pig carcasses was investigated in a cross-sectional study that was carried out in three selected slaughter slabs in morogoro municipality, tanzania. before sampling, the slab hygiene, slaughter, carcass dressing, and meat handling was assessed. fecal samples were collected from 66 slaughter pigs at the kill floor. after slaughter, a 100-cm(2) area on medial surface of the thigh muscles of dressed carcasses was sampled using sterile cotton swab ...201120730490
change is good: variations in common biological mechanisms in the epsilonproteobacterial genera campylobacter and helicobacter.microbial evolution and subsequent species diversification enable bacterial organisms to perform common biological processes by a variety of means. the epsilonproteobacteria are a diverse class of prokaryotes that thrive in diverse habitats. many of these environmental niches are labeled as extreme, whereas other niches include various sites within human, animal, and insect hosts. some epsilonproteobacteria, such as campylobacter jejuni and helicobacter pylori, are common pathogens of humans tha ...201121372321
related antimicrobial resistance genes detected in different bacterial species co-isolated from swine fecal samples.a potential factor leading to the spread of antimicrobial resistance (ar) in bacteria is the horizontal transfer of resistance genes between bacteria in animals or their environment. to investigate this, swine fecal samples were collected on-farm and cultured for escherichia coli, salmonella enterica, campylobacter spp., and enterococcus spp. which are all commonly found in swine. forty-nine of the samples from which all four bacteria were recovered were selected yielding a total of 196 isolates ...201121385089
fitness cost of fluoroquinolone resistance in campylobacter coli and campylobacter jejuni.in this study, the fitness cost of fluoroquinolone resistance was evaluated in vitro, on food matrices, and in vivo, using campylobacter coli and campylobacter jejuni in vitro selected mutants. in vitro, the growth rate of the susceptible (wild type) and resistant (mutant) strains did not differ when cultured separately. however, by conducting sequential passages of mixed cultures, the ratio of the resistant mutant to the susceptible strain decreased for c. coli but not for c. jejuni. when the w ...201121388301
longitudinal on-farm study of the development of antimicrobial resistance in campylobacter coli from pigs before and after danofloxacin and tylosin treatments.effects of danofloxacin or consecutive fluoroquinolone and macrolide treatments on resistance development in campylobacter have remained uncharacterised. therefore we analysed the development of resistance in porcine campylobacter coli before and after danofloxacin and tylosin treatments at a farrowing farm. danofloxacin-treated (n=12, group a) and control pigs (n=15, group b) were subsequently treated with tylosin and sampled longitudinally. c. coli were isolated and susceptibilities to ciprofl ...201121397412
eleutherine americana: a candidate for the control of campylobacter species.the antibacterial activity of ethanolic extracts of selected thai medicinal plants (rhodomyrtus tomentosa (aiton) hassk., quercus infectoria g. olivier, and eleutherine americana merr.) against campylobacter spp. was investigated. sixty-five campylobacter, including 39 isolates from humans and 26 isolates from chicken samples, were tested. reference campylobacter spp. that are commonly encountered in gastroenteritis were included. the ethanolic extract of e. americana demonstrated good antibacte ...201121406364
a novel immunity system for bacterial nucleic acid degrading toxins and its recruitment in various eukaryotic and dna viral systems.the use of nucleases as toxins for defense, offense or addiction of selfish elements is widely encountered across all life forms. using sensitive sequence profile analysis methods, we characterize a novel superfamily (the sukh superfamily) that unites a diverse group of proteins including smi1/knr4, pgs2, fbxo3, skip16, syd, herpesviral us22, irs1 and trs1, and their bacterial homologs. using contextual analysis we present evidence that the bacterial members of this superfamily are potential imm ...201121306995
detection and genotypic differentiation of campylobacter jejuni and campylobacter coli strains from laying hens by multiplex pcr and fla-typing.in total, 26 campylobacter (c.) strains, isolated from liver, spleen, caecal or jejunal content of laying hens from different flocks were examined. in these flocks a drop in egg production, an increasing mortality and livers with whitish-grey lesions as post-mortem finding were observed. suspected campylobacter colonies were differentiated using a modified m-pcr in 13 campylobacter jejuni and 13 campylobacter coli strains. all isolates were characterised by typing of the flaa and flab gene each ...201121349563
comparison of cape town and skirrow's campylobacter isolation protocols in humans and broilers in morogoro, tanzania.comparison of cape town and skirrow's protocols used in isolation of campylobacter in humans and broilers was carried out in a cross-sectional study in morogoro, tanzania. a total of 176 and 158 human stool and broiler intestinal samples were collected, respectively. while human stool samples were collected from selected health centers, broiler intestinal samples were obtained from selected farms and chicken markets. samples were inoculated and cultured in duplicate using two protocols and preva ...201121359592
automated identification of medically important bacteria by 16s rrna gene sequencing using a novel comprehensive database, 16spathdb.despite the increasing use of 16s rrna gene sequencing, interpretation of 16s rrna gene sequence results is one of the most difficult problems faced by clinical microbiologists and technicians. to overcome the problems we encountered in the existing databases during 16s rrna gene sequence interpretation, we built a comprehensive database, 16spathdb (http://147.8.74.24/16spathdb) based on the 16s rrna gene sequences of all medically important bacteria listed in the manual of clinical microbiology ...201121389154
campylobacter jejuni, campylobacter coli, and cytolethal distending toxin genes in laying hens.as no data are available on the prevalence of cytolethal distending toxin (cdt) genes carried by campylobacter spp. in laying hens, this study was conducted with the aim to evaluate the prevalence of both campylobacter spp. and cdt genes in 1680 laying hens from four different farms. the samples were analyzed by culture methods and by polymerase chain reaction. campylobacter spp. were isolated from 1097/1680 cloacal swabs. among the isolates, 913 were identified as campylobacter jejuni whereas 3 ...201121500644
regulation of oxidative stress response by cosr, an essential response regulator in campylobacter jejuni.cosr (campylobacteroxidative stress regulator; cj0355c) is an ompr-type response regulator essential for the viability of campylobacter jejuni, a leading foodborne pathogen causing human gastroenteritis worldwide. despite importance, the function of cosr remains completely unknown mainly because of cell death caused by its knockout mutation. to overcome this technical limitation, in this study, antisense technology was used to investigate the regulatory function of cosr by modulating the level o ...201121811584
etiology of diarrhea in young children and patterns of antibiotic resistance in cambodia.little is known about diarrhea etiology and antibiotic resistance in developing countries where diarrhea is a major public health problem.201121412204
campylobacter contamination of broiler caeca and carcasses at the slaughterhouse and correlation with salmonella contamination.in order to estimate the prevalence of campylobacter spp. and salmonella spp. on broiler chicken carcasses and the prevalence of campylobacter spp. in caeca, 58 french slaughterhouses were investigated in 2008. enumeration of campylobacter spp. was also performed in order to study the relation between caeca and carcass contamination. a pool of 10 caeca and one carcass were collected from 425 different batches over a 12-month period in 2008. salmonella was isolated on 32 carcasses leading to a pr ...201121569927
diarrheagenic pathogens in polymicrobial infections.during systematic active surveillance of the causes of diarrhea in patients admitted to the infectious diseases and beliaghata general hospital in kolkata, india, we looked for 26 known gastrointestinal pathogens in fecal samples from 2,748 patients. samples from about one-third (29%) of the patients contained multiple pathogens. polymicrobial infections frequently contained vibrio cholerae o1 and rotavirus. when these agents were present, some co-infecting agents were found significantly less o ...201121470448
genome and characterization of phages bcep22 and bcepil02, founders of a novel phage type in burkholderia cenocepacia.within the burkholderia cepacia complex (bcc), b. cenocepacia is the most common species associated with aggressive infections in the lungs of cystic fibrosis patients, causing disease that is often refractive to treatment by antibiotics. phage therapy may be a potential alternative form of treatment for these infections. here we describe the genome of the previously described therapeutic b. cenocepacia podophage bcepil02 and its close relative, bcep22. phage bcep22 was found to contain a circul ...201121804006
efficacy of uv light treatment for the microbiological decontamination of chicken, associated packaging, and contact surfaces.uv light was investigated for the decontamination of raw chicken, associated packaging, and contact surfaces. the uv susceptibilities of a number of campylobacter isolates (seven campylobacter jejuni isolates and three campylobacter coli isolates), escherichia coli atcc 25922, and salmonella enterica serovar enteritidis atcc 10376 in liquid media were also investigated. from an initial level of 7 log cfu/ml, no viable campylobacter cells were detected following exposure to the most intense uv do ...201121477470
antimicrobial resistance and molecular subtyping of campylobacter jejuni and campylobacter coli from retail meats.campylobacter isolates (n = 297; 202 c. jejuni and 95 c. coli isolates) recovered from 2,513 retail meat samples (chicken breasts, ground turkey, ground beef, and pork chops) were examined for antimicrobial susceptibility. the isolates were further analyzed for genetic relatedness by pulsed-field gel electrophoresis (pfge) using smai and kpni restriction enzymes, and a subset of isolates (n = 174) were subtyped by multilocus sequence typing (mlst). the resistance most frequently observed was tha ...201121477476
l-fucose utilization provides campylobacter jejuni with a competitive advantage.campylobacter jejuni is a prevalent gastrointestinal pathogen in humans and a common commensal of poultry. when colonizing its hosts, c. jejuni comes into contact with intestinal carbohydrates, including l-fucose, released from mucin glycoproteins. several strains of c. jejuni possess a genomic island (cj0480c-cj0490) that is up-regulated in the presence of both l-fucose and mucin and allows for the utilization of l-fucose as a substrate for growth. strains possessing this genomic island show in ...201121482772
occurrence of thermotolerant campylobacter spp. on eggshells: a missing link for food-borne infections?we analyzed the prevalence of thermotolerant campylobacter spp. compared that of to salmonella spp. in raw yolk and on eggshells. a total of 2,710 eggs were investigated for each bacterium. viable bacteria were found in 4.1% (campylobacter spp.) and 1.1% (salmonella spp.) of the eggshell samples, whereas the egg yolk samples were negative for both bacteria.201121498761
influence of cell surface hydrophobicity on attachment of campylobacter to abiotic surfaces.this work aimed to investigate the influence of physicochemical properties and prior mode of growth (planktonic or sessile culture) on attachment of 13 campylobacter jejuni strains and 5 campylobacter coli strains isolated from chicken samples to three abiotic surfaces: stainless steel, glass and polyurethane. water contact angle and zeta potential measurements indicated that the strains varied with respect to surface hydrophobicity (17.6 ± 1.5 to 53.0 ± 2.3°) and surface charge (-3.3 ± 0.4 to - ...201121569937
metagenome of the gut of a malnourished child.abstract: background: malnutrition, a major health problem, affects a significant proportion of preschool children in developing countries. the devastating consequences of malnutrition include diarrhoea, malabsorption, increased intestinal permeability and suboptimal immune response etc. nutritional interventions and dietary solutions have not been effective for treatment of malnutrition till date. metagenomic procedures allow one to access the complex cross-talk between the gut and its microbia ...201121599906
niche segregation and genetic structure of campylobacter jejuni populations from wild and agricultural host species.bacterial populations can display high levels of genetic structuring but the forces that influence this are incompletely understood. here, by combining modelling approaches with multilocus sequence data for the zoonotic pathogen campylobacter, we investigated how ecological factors such as niche (host) separation relate to population structure. we analysed seven housekeeping genes from published c. jejuni and c. coli isolate collections from a range of food and wild animal sources as well as abi ...201121762392
genomic species are ecological species as revealed by comparative genomics in agrobacterium tumefaciens.the definition of bacterial species is based on genomic similarities, giving rise to the operational concept of genomic species, but the reasons of the occurrence of differentiated genomic species remains largely unknown. we used the agrobacterium tumefaciens species complex, and particularly the genomic species presently called genomovar g8, which includes the sequenced strain c58, to test the hypothesis of genomic species having specific ecological adaptations possibly involved in the speciati ...201121795751
differentiation of campylobacter species by surface-enhanced laser desorption/ionization-time-of-flight mass spectrometry.abstract the genus campylobacter contains several, widespread pathogens causing food-borne diseases of zoonotic nature in humans. in case of outbreaks, the differentiation of closely related campylobacter is essential for epidemiological studies, which investigate the routes of geographical spread and ways of transmission. recent advances in mass spectrometry (ms) have shown that matrix-assisted laser desorption/ionization-time-of-flight (maldi-tof) ms is a valuable tool for speciation of bacter ...201121524195
influence of season and geography on campylobacter jejuni and c. coli subtypes in housed broiler flocks reared in great britain.geographical and seasonal variation in the incidence and prevalence of campylobacter jejuni and c. coli in housed broiler flocks reared in great britain in 2004 to 2006 was investigated in this study. ceca (30) from 797 flocks, not subject to prior partial depopulation and reared on 211 farms, were examined individually for the presence of campylobacter spp. the best-fitting climatic factors explained approximately 46% of the prevalence of campylobacter-colonized flocks at slaughter and consiste ...201121460110
campylobacter from sows in farrow-to-finish pig farms: risk indicators and genetic diversity.sows have been identified as a source of campylobacter contamination in piglets. we carried out a one-year study, in 2008, at 53 farrow-to-finish farms in brittany, france, to determine the proportion of sows excreting campylobacter. we also determined the genotypes of the campylobacter isolates. moreover, generalized estimating equations including repeated effects were used to assess the association between management practices and farm characteristics, and risk of campylobacter shedding by sow ...201121802224
rapid identification and quantification of campylobacter coli and campylobacter jejuni by real-time pcr in pure cultures and in complex samples.abstract: background: campylobacter spp., especially campylobacter jejuni (c. jejuni) and campylobacter coli (c. coli), are recognized as the leading human foodborne pathogens in developed countries. livestock animals carrying campylobacter pose an important risk for human contamination. pigs are known to be frequently colonized with campylobacter, especially c. coli, and to excrete high numbers of this pathogen in their faeces. molecular tools, notably real-time pcr, provide an effective, rapid ...201121600037
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