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demographic and clinical characteristics of campylobacter bacteremia in children with and without predisposing factors.campylobacter, a common cause of childhood gastroenteritis, rarely causes bacteremia, which is reported mainly in immune-compromised children. our aim was to compare demographic and clinical characteristics of childhood campylobacter bacteremia (cb) between children with and without risk factors for cb.201323694835
prevalence, associated risk factors and antimicrobial susceptibility pattern of campylobacter species among under five diarrheic children at gondar university hospital, northwest ethiopia.recent reports indicate that campylobacter species are becoming one of the leading causes of bacterial diarrhoeal disease worldwide and most of the isolates are resistant to different antibiotics. this study aimed at determining the prevalence, associated risk factors and susceptibility pattern of campylobacter species in under-five diarrheic children.201323694714
prevalence of campylobacter jejuni and campylobacter coli species in cats and dogs from bydgoszcz (poland) region.the aim of this study was to investigate the role of cats and dogs as a potential reservoir of campylobacter spp. rectal swabs from 83 dogs and 71 cats were examined. samples were obtained from the animals aged between 2 weeks and 24 months living in shelters, private households, farms and from veterinary clinics located in bydgoszcz region during routine check-up. campylobacter spp. were isolated from 4.81% dogs and 9.86% cats, respectively. c. jejuni was predominant in this study. all strains ...201323691584
enteropathic spondyloarthritis: from diagnosis to treatment.enteropathic arthritis (ea) is a spondyloarthritis (spa) which occurs in patients with inflammatory bowel diseases (ibds) and other gastrointestinal diseases. diagnosis is generally established on the medical history and physical examination. it was, generally, made according to the european spondyloarthropathy study group (essg) criteria. rheumatic manifestations are the most frequent extraintestinal findings of ibd with a prevalence between 17% and 39%, and ibd is associated, less frequently, ...201323690825
comparison of predicted epimerases and reductases of the campylobacter jejuni d-altro- and l-gluco-heptose synthesis pathways.uniquely modified heptoses found in surface carbohydrates of bacterial pathogens are potential therapeutic targets against such pathogens. our recent biochemical characterization of the gdp-6-deoxy-d-manno- and gdp-6-deoxy-d-altro-heptose biosynthesis pathways has provided the foundation for elucidation of the more complex l-gluco-heptose synthesis pathway of campylobacter jejuni strain nctc 11168. in this work we use gdp-4-keto,6-deoxy-d-lyxo-heptose as a surrogate substrate to characterize thr ...201323689373
zoonoses in pet birds: review and perspectives.pet birds are a not-so-well known veterinarian's clientship fraction. bought individually or in couples, as families often do (which is a lucrative business for pet shops or local breeders) or traded (sometimes illegally) for their very high genetic or exotic value, these birds, commonly canaries, parakeets or parrots, are regularly sold at high prices. these animals, however, are potential carriers and/or transmitters of zoonotic diseases. some of them could have an important impact on human he ...201323687940
rab3gap1 mediates exocytosis of claudin-1 and tight junction formation during epidermal barrier acquisition.epidermal barrier acquisition during late murine gestation is accompanied by an increase in akt kinase activity and cjun dephosphorlyation. the latter is directed by the ppp2r2a regulatory subunit of the pp2a phosphatase. this was accompanied by a change of claudin-1 localisation to the cell surface and interaction between occludin and claudin-1 which are thought to be required for tight junction formation. the aim of this study was to determine the nature of the barrier defect caused by the los ...201323685254
iron in infection and immunity.iron is an essential nutrient for both humans and pathogenic microbes. because of its ability to exist in one of two oxidation states, iron is an ideal redox catalyst for diverse cellular processes including respiration and dna replication. however, the redox potential of iron also contributes to its toxicity; thus, iron concentration and distribution must be carefully controlled. given the absolute requirement for iron by virtually all human pathogens, an important facet of the innate immune sy ...201323684303
campylobacter jejuni carbon starvation protein a (csta) is involved in peptide utilization, motility and agglutination, and has a role in stimulation of dendritic cells.campylobacter jejuni is the most frequent cause of severe gastroenteritis in the developed world. the major symptom of campylobacteriosis is inflammatory diarrhoea. the molecular mechanisms of this infection are poorly understood compared to those of less frequent disease-causing pathogens. in a previous study, we identified c. jejuni proteins that antibodies in human campylobacteriosis patients reacted with. one of the immunogenic proteins identified (cj0917) displays homology to carbon starvat ...201323682166
burden and aetiology of diarrhoeal disease in infants and young children in developing countries (the global enteric multicenter study, gems): a prospective, case-control study.diarrhoeal diseases cause illness and death among children younger than 5 years in low-income countries. we designed the global enteric multicenter study (gems) to identify the aetiology and population-based burden of paediatric diarrhoeal disease in sub-saharan africa and south asia.201323680352
potential applications for annona squamosa leaf extract in the treatment and prevention of foodborne bacterial disease.foodborne disease is a major public health problem. the present study examined annona squamosa leaves, which are traditionally used to treat diarrhea and other infections, for their potential to be used in modern food safety or medicine. active constituents were partially purified by ethanol extraction and column chromatography. mics of the extract were 62.5 to 125 microg/ml against bacillus cereus, listeria monocytogenes and staphylococcus aureus, and 250 microg/ml against campylobacter jejuni. ...201323678817
role of motab in adherence and internalization in polarized caco-2 cells and in cecal colonization of campylobacter jejuni.campylobacter jejuni, a gram-negative motile bacterium commonly found in the chicken gastrointestinal tract, is one of the leading causes of bacterial gastroenteritis in humans worldwide. an intact and functional flagellum is important for c. jejuni virulence and colonization. to understand the role of c. jejuni motility in adherence and internalization in polarized caco-2 cells and in cecal colonization of chickens we constructed a c. jejuni nctc11168 v1 deltamotab mutant. the motab genes code ...201323678739
[molecular analysis of fluoroquinolones and macrolides resistance in campylobacter jejuni isolates from humans, bovine and chicken meat].campylobacter sp.- one of the leading causes of bacterial food-borne gastrointestinal illness worldwide- is increasingly resistant to fluoroquinolone and macrolide antimicrobials, which has become a major concern for public health.201323677151
comparative genome analysis of an avirulent and two virulent strains of avian pasteurella multocida reveals candidate genes involved in fitness and pathogenicity.pasteurella multocida is the etiologic agent of fowl cholera, a highly contagious and severe disease of poultry causing significant mortality and morbidity throughout the world. all types of poultry are susceptible to fowl cholera. turkeys are most susceptible to the peracute/acute forms of the disease while chickens are most susceptible to the acute and chronic forms of the disease. the whole genome of the pm70 strain of p. multocida was sequenced and annotated in 2001. the pm70 strain is not v ...201323672515
comprehensive antigen screening identifies moraxella catarrhalis proteins that induce protection in a mouse pulmonary clearance model.moraxella catarrhalis is one of the three most common causative bacterial pathogens of otitis media, however no effective vaccine against m. catarrhalis has been developed so far. to identify m. catarrhalis vaccine candidate antigens, we used carefully selected sera from children with otitis media and healthy individuals to screen small-fragment genomic libraries that are expressed to display frame-selected peptides on a bacterial cell surface. this antigenome technology led to the identificatio ...201323671716
severe guillain-barré syndrome in a patient receiving anti-tnf therapy. consequence or coincidence. a case-based review.the adverse effects of anti-tumour necrosis factor alpha (tnfα) drugs include an increase in the risk of infections, congestive heart failure, lupus-like syndrome, and the onset or worsening of various demyelinating diseases such as, multiple sclerosis, optic neuritis, and guillain-barrè syndrome (gbs), among others. we describe the case of a patient who developed gbs while she was on treatment with adalimumab. a 50-year-old woman with rheumatoid arthritis (ra) was admitted to the hospital due t ...201323666317
occurrence of campylobacter and salmonella in ducks and duck eggs in selangor, malaysia.the importance of campylobacter and salmonella as foodborne pathogens is well recognised globally. a recent work in penang found ducks in commercial farms were infected with these organisms. the aim of the study was to detect the presence of campylobacter and salmonella in ducks and salmonella in duck eggs in farms in a small part of selangor. cloacal swabs were obtained from 75 ducks and 30 duck eggs from three farms. the isolation and identification of campylobacter and salmonella were done us ...201323665722
phytochemical analysis and antibacterial evaluation of the ethyl acetate extract of the stem bark of bridelia micrantha.plant cells fundamentally are chemical factories containing a rich supply of therapeutically useful phytocompounds that have the potential of being developed into potent antimicrobial agents.201323661993
identification of bacterial protein o-oligosaccharyltransferases and their glycoprotein substrates.o-glycosylation of proteins in neisseria meningitidis is catalyzed by pgll, which belongs to a protein family including waal o-antigen ligases. we developed two hidden markov models that identify 31 novel candidate pgll homologs in diverse bacterial species, and describe several conserved sequence and structural features. most of these genes are adjacent to possible novel target proteins for glycosylation. we show that in the general glycosylation system of n. meningitidis, efficient glycosylati ...201323658772
life without trnaarg-adenosine deaminase tada: evolutionary consequences of decoding the four cgn codons as arginine in mycoplasmas and other mollicutes.in most bacteria, two trnas decode the four arginine cgn codons. one trna harboring a wobble inosine (trna(arg)icg) reads the cgu, cgc and cga codons, whereas a second trna harboring a wobble cytidine (trna(arg)ccg) reads the remaining cgg codon. the reduced genomes of mycoplasmas and other mollicutes lack the gene encoding trna(arg)ccg. this raises the question of how these organisms decode cgg codons. examination of 36 mollicute genomes for genes encoding trna(arg) and the tada enzyme, respons ...201323658230
pif1 family helicases suppress genome instability at g-quadruplex motifs.the saccharomyces cerevisiae pif1 helicase is the prototypical member of the pif1 dna helicase family, which is conserved from bacteria to humans. here we show that exceptionally potent g-quadruplex unwinding is conserved among pif1 helicases. moreover, pif1 helicases from organisms separated by more than 3 billion years of evolution suppressed dna damage at g-quadruplex motifs in yeast. the g-quadruplex-induced damage generated in the absence of pif1 helicases led to new genetic and epigenetic ...201323657261
oral immunization with cholera toxin provides protection against campylobacter jejuni in an adult mouse intestinal colonization model.immunity to campylobacter jejuni, a major diarrheal pathogen, is largely penner serotype specific. for broad protection, a vaccine should be based on a common antigen(s) present in all strains. in our previous study (m. j. albert, s. haridas, d. steer, g. s. dhaunsi, a. i. smith, and b. adler, infect. immun. 75:3070-3073, 2007), we demonstrated that antibody to cholera toxin (ct) cross-reacted with the major outer membrane proteins (momps) of all campylobacter jejuni strains tested. in the curre ...201323653448
gut microbiota, tight junction protein expression, intestinal resistance, bacterial translocation and mortality following cholestasis depend on the genetic background of the host.failure of the intestinal barrier is a characteristic feature of cholestasis. we have previously observed higher mortality in c57bl/6j compared with a/j mice following common bile duct ligation (cbdl). we hypothesized the alteration in gut barrier function following cholestasis would vary by genetic background. following one week of cbdl, jejunal teer was significantly reduced in each ligated mouse compared with their sham counterparts; moreover, jejunal teer was significantly lower in both sham ...201323652772
short and long-term genome stability analysis of prokaryotic genomes.gene organization dynamics is actively studied because it provides useful evolutionary information, makes functional annotation easier and often enables to characterize pathogens. there is therefore a strong interest in understanding the variability of this trait and the possible correlations with life-style. two kinds of events affect genome organization: on one hand translocations and recombinations change the relative position of genes shared by two genomes (i.e. the backbone gene order); on ...201323651581
the dot/icm effector sdha is necessary for virulence of legionella pneumophila in galleria mellonella and a/j mice.legionella pneumophila is an intracellular bacterium that resides within amoebae and macrophages in a specialized compartment termed the legionella-containing vacuole (lcv). as well as providing an intracellular niche for replication, the lcv helps to prevent the release of bacterial components into the cytoplasm. recognition of these components as danger signals by the host activates immune responses leading to clearance of the bacterium. here, we examined the role of two important virulence fa ...201323649096
immunity to bacterial infection in the chicken.bacterial infections remain important to the poultry industry both in terms of animal and public health, the latter due to the importance of poultry as a source of foodborne bacterial zoonoses such as salmonella and campylobacter. as such, much focus of research to the immune response to bacterial infection has been to salmonella. in this review we will focus on how research on avian salmonellosis has developed our understanding of immunity to bacteria in the chicken from understanding the role ...201323648643
occurrence and population density of campylobacter jejuni in irrigation ponds on produce farms in the suwannee river watershed.campylobacter spp., especially campylobacter jejuni, are common causal agents of gastroenteritis globally. poultry, contaminated water, and fresh produce are considered to be the main sources for infection by this pathogen. in this study, occurrence and population density of c. jejuni from vegetable irrigation ponds in the suwannee river watershed were investigated and the relationship to environmental factors was analyzed. two water samples were collected from each of 10 ponds every month from ...201323647347
crystal structure of peroxide stress regulator from streptococcus pyogenes provides functional insights into the mechanism of oxidative stress sensing.regulation of oxidative stress responses by the peroxide stress regulator (perr) is critical for the in vivo fitness and virulence of group a streptococcus. to elucidate the molecular mechanism of dna binding, peroxide sensing, and gene regulation by perr, we performed biochemical and structural characterization of perr. sequence-specific dna binding by perr does not require regulatory metal occupancy. however, metal binding promotes higher affinity perr-dna interactions. perr metallated with ir ...201323645680
characterization of the campylobacter jejuni cryptic plasmid ptiw94 recovered from wild birds in the southeastern united states.the complete nucleotide sequence was determined for a cryptic plasmid, ptiw94, recovered from several campylobacter jejuni isolates from wild birds in the southeastern united states. ptiw94 is a circular molecule of 3860 nucleotides, with a g+c content (31.0%) similar to that of many campylobacter spp. genomes. a typical origin of replication, with iteron sequences, was identified upstream of dna sequences that demonstrated similarity to replication initiation proteins. a total of five open read ...201323639726
in vivo modulation of campylobacter jejuni virulence in response to environmental stress.campylobacters have developed a number of mechanisms for responding to environmental conditions, although the different virulence properties of these cells following exposure to stress are still poorly understood. we analyzed in vitro stress responses and the consequent in vivo modulation of campylobacter jejuni pathogenicity in balb/c mice, as a result of the exposure of the c. jejuni to environmental stress (starvation, oxidative stress, heat shock). in vitro, the influence of starvation and o ...201323638846
salmonella uses energy taxis to benefit from intestinal inflammation.chemotaxis enhances the fitness of salmonella enterica serotype typhimurium (s. typhimurium) during colitis. however, the chemotaxis receptors conferring this fitness advantage and their cognate signals generated during inflammation remain unknown. here we identify respiratory electron acceptors that are generated in the intestinal lumen as by-products of the host inflammatory response as in vivo signals for methyl-accepting chemotaxis proteins (mcps). three mcps, including trg, tsr and aer, enh ...201323637594
construction of escherichia coli strains with chromosomally integrated expression cassettes for the synthesis of 2'-fucosyllactose.the trisaccharide 2'-fucosyllactose (2'-fl) is one of the most abundant oligosaccharides found in human milk. due to its prebiotic and anti-infective properties, 2'-fl is discussed as nutritional additive for infant formula. besides chemical synthesis and extraction from human milk, 2'-fl can be produced enzymatically in vitro and in vivo. the most promising approach for a large-scale formation of 2'-fl is the whole cell biosynthesis in escherichia coli by intracellular synthesis of gdp-l-fucose ...201323635327
campylobacter jejuni lipooligosaccharide sialylation, phosphorylation, and amide/ester linkage modifications fine-tune human toll-like receptor 4 activation.campylobacter jejuni is a leading cause of acute gastroenteritis. c. jejuni lipooligosaccharide (los) is a potent activator of toll-like receptor (tlr) 4-mediated innate immunity. structural variations of the los have been previously reported in the oligosaccharide (os) moiety, the disaccharide lipid a (la) backbone, and the phosphorylation of the la. here, we studied los structural variation between c. jejuni strains associated with different ecological sources and analyzed their ability to act ...201223629657
campylobacter jejuni lipooligosaccharide sialylation, phosphorylation, and amide/ester linkage modifications fine-tune human toll-like receptor 4 activation.campylobacter jejuni is a leading cause of acute gastroenteritis. c. jejuni lipooligosaccharide (los) is a potent activator of toll-like receptor (tlr) 4-mediated innate immunity. structural variations of the los have been previously reported in the oligosaccharide (os) moiety, the disaccharide lipid a (la) backbone, and the phosphorylation of the la. here, we studied los structural variation between c. jejuni strains associated with different ecological sources and analyzed their ability to act ...201223629657
circovirus in tissues of dogs with vasculitis and hemorrhage.we characterized the complete genome of a novel dog circovirus (dogcv) from the liver of a dog with severe hemorrhagic gastroenteritis, vasculitis, and granulomatous lymphadenitis. dogcv was detected by pcr in fecal samples from 19/168 (11.3%) dogs with diarrhea and 14/204 (6.9%) healthy dogs and in blood from 19/409 (3.3%) of dogs with thrombocytopenia and neutropenia, fever of unknown origin, or past tick bite. co-infection with other canine pathogens was detected for 13/19 (68%) dogcv-positiv ...201323628223
secondary membranous nephropathy associated with guillain-barré syndrome.membranous nephropathy (mn) is one of the most common causes of nephrotic syndrome (ns) in adults. it may be primary, usually mediated by igg4 anti-phospholipase a2 autoantibodies or secondary to various other conditions. guillain- barré syndrome (gbs) has been associated with mn, but a cause and effect relation has not been proven. we present a case of concurrent development of gbs and severe ns, with renal biopsy demonstrating mn. igg4 stain was negative, indicating that most likely, the mn wa ...201323626596
enumeration of salmonella and campylobacter spp. in environmental farm samples and processing plant carcass rinses from commercial broiler chicken flocks.a prospective cohort study was performed to evaluate the prevalences and loads of salmonella and campylobacter spp. in farm and processing plant samples collected from 55 commercial broiler chicken flocks. environmental samples were collected from broiler houses within 48 h before slaughter, and carcass rinses were performed on birds from the same flocks at 4 different stages of processing. salmonella was detected in farm samples of 50 (90.9%) flocks and in processing samples of 52 (94.5%) flock ...201323624481
the role of epsilonproteobacteria in children with gastroenteritis.a polymerase chain reaction-denaturing gradient gel electrophoresis method was used to examine 50 stool samples from children in belgium with gastroenteritis for an extensive range of epsilonproteobacteria species. during the 3-month study period, campylobacter concisus was the most common species. our observations suggest that c. concisus displays similar microbiologic and clinical features as campylobacter jejuni.201323624432
cytochrome bd-i in escherichia coli is less sensitive than cytochromes bd-ii or bo'' to inhibition by the carbon monoxide-releasing molecule, corm-3: n-acetylcysteine reduces co-rm uptake and inhibition of respiration.co-releasing molecules (co-rms) are potential therapeutic agents, able to deliver co - a critical gasotransmitter - in biological environments. co-rms are also effective antimicrobial agents; although the mechanisms of action are poorly defined, haem-containing terminal oxidases are primary targets. nevertheless, it is clear from several studies that the effects of co-rms on biological systems are frequently not adequately explained by the release of co: co-rms are generally more potent inhibito ...201323624261
using campylobacter spp. and escherichia coli data and bayesian microbial risk assessment to examine public health risks in agricultural watersheds under tile drainage management.human campylobacteriosis is the leading bacterial gastrointestinal illness in canada; environmental transmission has been implicated in addition to transmission via consumption of contaminated food. information about campylobacter spp. occurrence at the watershed scale will enhance our understanding of the associated public health risks and the efficacy of source water protection strategies. the overriding purpose of this study is to provide a quantitative framework to assess and compare the rel ...201323623467
marginal zone lymphoma: old, new, targeted, and epigenetic therapies.marginal zone lymphoma (mzl) is an indolent b-cell lymphoma arising from marginal zone b-cells present in lymph nodes and extranodal tissues. mzl comprises 5-17% of all non-hodgkin's lymphomas in adults. the world health organization categorizes mzl into three distinct types based on their site of impact: (1) splenic marginal zone lymphoma (smzl); (2) nodal marginal zone lymphoma (nmzl); (3) extranodal mucosa-associated lymphoid tissue (malt) lymphoma, which can be subdivided into gastric and no ...201223616915
variation in the complex carbohydrate biosynthesis loci of acinetobacter baumannii genomes.extracellular polysaccharides are major immunogenic components of the bacterial cell envelope. however, little is known about their biosynthesis in the genus acinetobacter, which includes a. baumannii, an important nosocomial pathogen. whether acinetobacter sp. produce a capsule or a lipopolysaccharide carrying an o antigen or both is not resolved. to explore these issues, genes involved in the synthesis of complex polysaccharides were located in 10 complete a. baumannii genome sequences, and th ...201323614028
investigation of virulence and cytolethal distending toxin genes in campylobacter spp. isolated from sheep in turkey.the presence of virulence and cytolethal distending toxin (cdt) genes was investigated in isolates of campylobacter jejuni, c. coli, c. lanienae, and c. lari that originated from intestinal contents and gallbladders of clinically healthy sheep. these genes have important roles in the pathogenicity of campylobacters. a total of 363 campylobacter isolates (221 c. jejuni, 135 c. coli, five c. lanienae, and two c. lari) were used in this study. the frequency of racr, dnaj, ciab, plda, flaa, and cadf ...201323611104
targeted delivery of lipid antigen to macrophages via the cd169/sialoadhesin endocytic pathway induces robust invariant natural killer t cell activation.invariant natural killer t (inkt) cells induce a protective immune response triggered by foreign glycolipid antigens bound to cd1d on antigen-presenting cells (apcs). a limitation of using glycolipid antigens to stimulate immune responses in human patients has been the inability to target them to the most effective apcs. recent studies have implicated phagocytic cd169(+) macrophages as major apcs in lymph nodes for priming inkt cells in mice immunized with glycolipid antigen in particulate form. ...201323610394
helicobacter pylori infection, chronic inflammation, and genomic transformations in gastric malt lymphoma.nowadays, it is believed that the main role in the development of gastric mucosa-associated lymphoid tissue (malt) lymphoma plays helicobacter pylori infection. this world-wide distributed bacteria is in charge of most cases of not only upper gastrointestinal tract disorders but also some of extragastric problems. constant stimulation of the immune system causes a b-lymphocytes proliferation, which is considered to be responsible for the neoplastic transformation. on the other hand, there are 10 ...201323606792
systematic application of multiplex pcr enhances the detection of bacteria, parasites, and viruses in stool samples.to determine whether systematic testing of faecal samples with a broad range multiplex pcr increases the diagnostic yield in patients with diarrhoea compared with conventional methods and a clinician initiated testing strategy.201323603249
spatial and numerical regulation of flagellar biosynthesis in polarly flagellated bacteria.control of surface organelle number and placement is a crucial aspect of the cell biology of many gram-positive and gram-negative bacteria, yet mechanistic insights into how bacteria spatially and numerically organize organelles are lacking. many surface structures and internal complexes are spatially restricted in the bacterial cell (e.g. type iv pili, holdfasts, chemoreceptors), but perhaps none show so many distinct patterns in terms of number and localization as the flagellum. in this review ...201323600726
interpreting infective microbiota: the importance of an ecological perspective.complex microbiota are being reported increasingly across a range of chronic infections, including those of the cystic fibrosis airways. such diversity fits poorly into classical models of sterile tissue infections, which generally involve one species, and where microbe-outcome associations usually imply causality. it has been suggested that microbiota at sites of infection could represent pathogenic entities, analogous to individual species. we argue that our ability to identify causality in mi ...201323598051
a review of vaccine development and research for industry animals in korea.vaccination has proven to be the most cost-effective strategy for controlling a wide variety of infectious diseases in humans and animals. for the last decade, veterinary vaccines have been substantially developed and demonstrated their effectiveness against many diseases. nevertheless, new vaccines are greatly demanded to effectively control newly- and re-emerging pathogens in livestock. however, development of veterinary vaccines is a challenging task, in part, due to a variety of pathogens, h ...201223596575
differential resuscitative effect of pyruvate and its analogues on vbnc (viable but non-culturable) salmonella.an environmental isolate of salmonella enteritidis (se), grown to the logarithmic phase, rapidly lost culturability by the addition of 3 mm h2o2 to cultures grown in luria-bertani (lb) medium; however, some h2o2-treated bacteria regained their culturability in m9 minimal medium, if sodium pyruvate was present at at least 0.3 mm. in addition, most pyruvate analogues, such as bromopyruvate or phenylpyruvate, did not show restoration activity similar to that of pyruvate, except in the case of α-ket ...201323595023
effect of spatial separation of pigs on spread of streptococcus suis serotype 9.the spread of an infectious agent in a population can be reduced by interfering in the infectiousness or susceptibility of individuals, and/or in their contact structure. the aim of this study was to quantify the effect of prevention of direct contact between infectious and susceptible pigs on the transmission of streptococcus suis (s. suis). in three replicate experiments, s. suis-free pigs were housed in boxes either in pairs (25 pairs) or alone (15 pigs). the distance between the boxes was ±1 ...201323593467
interferon-inducible mechanism of dendritic cell-mediated hiv-1 dissemination is dependent on siglec-1/cd169.human immunodeficiency virus type 1 (hiv-1) interactions with myeloid dendritic cells (dcs) can result in virus dissemination to cd4⁺ t cells via a trans infection pathway dependent on virion incorporation of the host cell derived glycosphingolipid (gsl), gm3. the mechanism of dc-mediated trans infection is extremely efficacious and can result in infection of multiple cd4⁺ t cells as these cells make exploratory contacts on the dc surface. while it has long been appreciated that activation of dc ...201323593001
bartonella henselae infection in a family experiencing neurological and neurocognitive abnormalities after woodlouse hunter spider bites.bartonella species comprise a group of zoonotic pathogens that are usually acquired by vector transmission or by animal bites or scratches.201323587343
diet, microbiome, and the intestinal epithelium: an essential triumvirate?the intestinal epithelium represents a critical barrier protecting the host against diverse luminal noxious agents, as well as preventing the uncontrolled uptake of bacteria that could activate an immune response in a susceptible host. the epithelial monolayer that constitutes this barrier is regulated by a meshwork of proteins that orchestrate complex biological function such as permeability, transepithelial electrical resistance, and movement of various macromolecules. because of its key role ...201323586037
development of a broad-range 23s rdna real-time pcr assay for the detection and quantification of pathogenic bacteria in human whole blood and plasma specimens.molecular methods are important tools in the diagnosis of bloodstream bacterial infections, in particular in patients treated with antimicrobial therapy, due to their quick turn-around time. here we describe a new broad-range real-time pcr targeting the 23s rdna gene and capable to detect as low as 10 plasmid copies per reaction of targeted bacterial 23s rdna gene. two commercially available dna extraction kits were evaluated to assess their efficiency for the extraction of plasma and whole bloo ...201323586027
[role of fliy gene in pathogenicity-associated chemotaxis and colonization of campylobacter jejuni].to construct a knockout fliy gene mutant strain of campylobacter jejuni for determining the role of fliy protein in flagellar movement related to bacterial motility, chemotaxis and colonization.201323584999
comparison of genotypes and antibiotic resistances of campylobacter jejuni and campylobacter coli on chicken retail meat and at slaughter.multilocus sequence typing (mlst) and antibiotic resistance patterns of campylobacter jejuni and campylobacter coli from retail chicken meat showed high overlap with isolates collected at slaughterhouses, indicating little selection along the production chain. they also showed significant common sequence types with human clinical isolates, revealing chicken meat as a likely source for human infection.201323584778
molecular detection of campylobacter spp. and fecal indicator bacteria during the northern migration of sandhill cranes (grus canadensis) at the central platte river.the risk to human health of the annual sandhill crane (grus canadensis) migration through nebraska, which is thought to be a major source of fecal pollution of the central platte river, is unknown. to better understand potential risks, the presence of campylobacter species and three fecal indicator bacterial groups (enterococcus spp., escherichia coli, and bacteroidetes) was assayed by pcr from crane excreta and water samples collected during their stopover at the platte river, nebraska, in 2010 ...201323584775
a crispr/cas system mediates bacterial innate immune evasion and virulence.crispr/cas (clustered regularly interspaced palindromic repeats/crispr-associated) systems are a bacterial defence against invading foreign nucleic acids derived from bacteriophages or exogenous plasmids. these systems use an array of small crispr rnas (crrnas) consisting of repetitive sequences flanking unique spacers to recognize their targets, and conserved cas proteins to mediate target degradation. recent studies have suggested that these systems may have broader functions in bacterial phys ...201323584588
optimized protocol for expression and purification of membrane-bound pglb, a bacterial oligosaccharyl transferase.asparagine-linked glycosylation (nlg) plays a significant role in a diverse range of cellular processes, including protein signaling and trafficking, the immunologic response, and immune system evasion by pathogens. a major impediment to nlg-related research is an incomplete understanding of the central enzyme in the biosynthetic pathway, the oligosaccharyl transferase (otase). characterization of the otase is critical for developing ways to inhibit, engineer, and otherwise manipulate the enzyme ...201323583934
the glove-like structure of the conserved membrane protein tatc provides insight into signal sequence recognition in twin-arginine translocation.in bacteria, two signal-sequence-dependent secretion pathways translocate proteins across the cytoplasmic membrane. although the mechanism of the ubiquitous general secretory pathway is becoming well understood, that of the twin-arginine translocation pathway, responsible for translocation of folded proteins across the bilayer, is more mysterious. tatc, the largest and most conserved of three integral membrane components, provides the initial binding site of the signal sequence prior to pore ass ...201323583035
mnsod in oxidative stress response-potential regulation via mitochondrial protein influx.the mitochondrial antioxidant manganese superoxide dismutase (mnsod) is encoded by genomic dna and its dismutase function is fully activated in the mitochondria to detoxify free radical o2(•-) generated by mitochondrial respiration. accumulating evidence shows an extensive communication between the mitochondria and cytoplasm under oxidative stress. not only is the mnsod gene upregulated by oxidative stress, but mnsod activity can be enhanced via the mitochondrial protein influx (mpi).201423581847
effect of antimicrobial growth promoter administration on the intestinal microbiota of beef cattle.antimicrobial growth promoters (agps) are antimicrobial agents administered to livestock in feed for prolonged periods to enhance feed efficiency. beef cattle are primarily finished in confined feeding operations in canada and the usa, and the administration of agps such as chlortetracycline and sulfamethazine (aureo s-700 g) is the standard. the impacts of agps on the intestinal microbiota of beef cattle are currently uncertain; it is documented that agps administered to beef cattle pass throug ...201323578222
case-control study on the role of enterotoxigenic bacteroides fragilis as a cause of diarrhea among children in kolkata, india.a total of 874 fecal specimens (446 diarrheal cases and 428 controls) from diarrheal children admitted in the infectious diseases hospital, kolkata and age and sex matched asymptomatic subjects from an urban community were assessed for the prevalence of enterotoxigenic bacteroides fragilis (etbf). isolates of b. fragilis were tested for the presence of enterotoxin gene (bft) by pcr. the detection rate of etbf was 7.2% (63 of 874 specimens) that prevailed equally in diarrheal cases and controls ( ...201323577134
campylobacter jejuni infections associated with unpasteurized milk--multiple states, 2012.in 2012, a multistate outbreak of campylobacter infections associated with unpasteurized milk resulted in 148 illnesses. a dairy with a pennsylvania department of agriculture unpasteurized milk permit and minimal deficiencies identified during inspection was the outbreak source, demonstrating the ongoing hazards of unpasteurized dairy products.201323575199
antimicrobial resistance of campylobacter jejuni isolated from chicken carcasses in the federal district, brazil.the aim of the present study was to perform microbiological isolation of campylobacter jejuni from chilled chicken carcasses marketed in the federal district of brazil and to subject the strains to an antibiogram. a total of 92 samples from chilled chicken carcasses were acquired, 18 of which (19.56%) tested positive for c. jejuni. a total of 16 strains were tested for susceptibility to eight antimicrobial drugs. all 16 strains were resistant to ciprofloxacin, 15 strains to nalidixic acid, strep ...201323575135
aerobic growth of campylobacter in media supplemented with c3-monocarboxylates and c4-dicarboxylates.experiments were conducted to examine aerobic growth of campylobacter spp. in basal media supplemented with c4-dicarboxylates (fumarate, succinate, or malate) and c3-monocarboxylates (pyruvate or lactate). basal medium was supplemented with 30 mm fumarate, succinate, or malate and 0 to 100 mm lactate or pyruvate; inoculated with 10(6) cfu/ml of campylobacter coli, campylobacter fetus, or campylobacter jejuni; then incubated aerobically at 37 °c for 72 h. optical density (od) of cultures was meas ...201323575134
lateral transfer, vertical translocation, and survival of inoculated bacteria during moisture enhancement of pork.lateral transfer, vertical translocation, and survival of bacteria during moisture enhancement of pork were investigated under laboratory conditions. in the first experiment, a pork loin was surface inoculated with escherichia coli biotype i and moisture enhanced with brine to 10%. after the inoculated loin had been injected, four uninoculated loins were processed in the same manner, without cleaning or sanitizing the injector equipment. samples were collected from both the surface and the inter ...201323575120
lessons learned and unlearned in periodontal microbiology.periodontal diseases are initiated by bacterial species living in polymicrobial biofilms at or below the gingival margin and progress largely as a result of the inflammation elicited by specific subgingival species. in the past few decades, efforts to understand the periodontal microbiota have led to an exponential increase in information about biofilms associated with periodontal health and disease. in fact, the oral microbiota is one of the best-characterized microbiomes that colonize the huma ...201323574465
epidemiological investigation of an outbreak of hepatitis a at a residential facility for the disabled, 2011.an outbreak of hepatitis a occurred at a residential facility for the disabled in july 10, 2011. this investigation was carried out to develop a response plan, and to find the infection source of the disease.201323573370
simultaneous detection of listeria monocytogenes and salmonella spp. in dairy products using real time pcr-melt curve analysis.the present investigation reports development of post real time pcr (rti-pcr) - melt curve analysis for simultaneous detection of listeria monocytogenes and salmonella spp. the optimal sybr green i (sg-i) concentration of 1.6 μm resulted in two specific peaks with melting temperature (tm) of 79.90 ± 0.39 °c and 86.29 ± 0.13 °c for l. monocytogenes and salmonella spp respectively. the detection sensitivity of the assay in reconstituted non-fat dried milk (nfdm; 11%) spiked with the target pathoge ...201123572847
simultaneous detection of listeria monocytogenes and salmonella spp. in dairy products using real time pcr-melt curve analysis.the present investigation reports development of post real time pcr (rti-pcr) - melt curve analysis for simultaneous detection of listeria monocytogenes and salmonella spp. the optimal sybr green i (sg-i) concentration of 1.6 μm resulted in two specific peaks with melting temperature (tm) of 79.90 ± 0.39 °c and 86.29 ± 0.13 °c for l. monocytogenes and salmonella spp respectively. the detection sensitivity of the assay in reconstituted non-fat dried milk (nfdm; 11%) spiked with the target pathoge ...201123572847
a culture-independent sequence-based metagenomics approach to the investigation of an outbreak of shiga-toxigenic escherichia coli o104:h4.identification of the bacterium responsible for an outbreak can aid in disease management. however, traditional culture-based diagnosis can be difficult, particularly if no specific diagnostic test is available for an outbreak strain.201323571589
effects of decontamination at varying contamination levels of campylobacter jejuni on broiler meat.when assessing effects of decontamination techniques on counts of campylobacter spp. on broiler meat, it is essential that the results reflect the variations that may exist. decontamination studies often use high inoculation levels (10(7) to 10(8) cfu) and one or few strains of campylobacter jejuni, thereby restricting the results to reflect only a limited part of the true situation. this study presents results from physical and chemical decontamination of broiler meat medallions using different ...201323571355
is allicin able to reduce campylobacter jejuni colonization in broilers when added to drinking water?reducing campylobacter shedding on the farm could result in a reduction of the number of human campylobacteriosis cases. in this study, we first investigated if allicin, allyl disulfide, and garlic oil extract were able to either prevent c. jejuni growth or kill c. jejuni in vitro. allyl disulfide and garlic oil extract reduced c. jejuni numbers in vitro below a detectable level at a concentration of 50 mg/kg (no lower concentrations were tested), whereas allicin reduced c. jejuni numbers below ...201323571353
impact and management of campylobacter in human medicine--us perspective.viruses, enteric bacteria and parasites can all produce similar syndromes of acute enteritis, although the pathophysiology and molecular pathogenesis may vary widely. the severity of acute enteritis varies greatly, and only a small fraction of cases undergo medical evaluation. there are over 200 000 000 episodes of acute enteritis annually in the usa, of which approximately 75 000 000 are foodborne. fewer than 20% of estimated cases have a known etiology. nearly half of the more than 4 000 000 c ...200223570172
genetic differentiation of campylobacter jejuni.genotyping methods have been developed and applied to differentiate campylobacter jejuni isolates over the last two decades. although a wealth of information was generated, the data are disappointingly complex and do not support simple models of transmission. several observations have apparently weakened the value and complicated the interpretation of genotyping methods. for several methods, instability of genotype has been demonstrated, due to recombinations with or without transformation. c. j ...200223570170
the ecology of campylobacter jejuni in avian and human hosts and in the environment.campylobacter jejuni, and its close relative c. coli, are highly successful bacteria colonizing the intestinal mucosa of a wide range of avian and animal hosts, including humans. in general, this colonization is either as a commensal, as in birds, or is an asymptomatic transient infection, as in livestock and in humans in endemic regions. however, in susceptible human populations, infection causes acute bacterial enteritis. the ecology of the organism for each outcome of colonization is consider ...200223570169
the microbial content of unexpired pasteurized milk from selected supermarkets in a developing country.to determine the presence and levels of microbes in unexpired pasteurized milk from randomly selected supermarkets in kingston, jamaica.201123569760
use of a web forum and an online questionnaire in the detection and investigation of an outbreak.a campylobacteriosis outbreak investigation provides relevant examples of how two web-based technologies were used in an outbreak setting and potential reasons for their usefulness. a web forum aided in outbreak detection and provided contextual insights for hypothesis generation and questionnaire development. an online questionnaire achieved a high response rate and enabled rapid preliminary data analysis that allowed for a targeted environmental investigation. the usefulness of these tools may ...201123569598
inverse metabolic engineering to improve escherichia coli as an n-glycosylation host.an inverse metabolic engineering strategy was used to select for escherichia coli cells with an increased capability to n-glycosylate a specific target protein. we developed a screen for e. coli cells containing extra-chromosomal dna fragments for improved ability to add precise sugar groups onto the acra protein using the glycosylation system from campylobacter jejuni. four different sized (1, 2, 4, and 8 kb) genomic dna libraries were screened, and the sequences that conferred a yield advantag ...201323568537
risk factor analysis may provide clues to diarrhea prevention in outdoor-housed rhesus macaques (macaca mulatta).seventy-five percent of rhesus macaques at national primate research centers are housed outside. annually, 15-39% of these animals experience diarrhea and require veterinary treatment for dehydration, electrolyte imbalance, or weight loss. an estimated 21-33% of these patients will die or be euthanized. many studies have explored the various infectious etiologies of non-human primate diarrhea. however, there is little published information on diarrhea incidence rates and risk factors in outdoor- ...201323568382
real-time polymerase chain reaction for detection of strongyloides stercoralis in stool.the use of real-time polymerase chain reaction (pcr) for detection of strongyloides stercoralis in stool has recently been described. we compared five dna extraction methods by using normal human stool spiked with strongyloides ratti and tested by using a real-time pcr. the powersoil kit was found to be the best technique in terms of sensitivity and ease of use. the pcr detected dna extracted from one spiked s. ratti larva diluted 10⁻². the powersoil kit was then used to extract dna from 160 hum ...201323568289
the htra protease of borrelia burgdorferi degrades outer membrane protein bmpd and chemotaxis phosphatase chex.borrelia burgdorferi, the spirochaetal agent of lyme disease, codes for a single htra protein, htrabb (bb0104) that is homologous to degp of escherichia coli (41% amino acid identity). htrabb shows physical and biochemical similarities to degp in that it has the trimer as its fundamental unit and can degrade casein via its catalytic serine. recombinant htrabb exhibits proteolytic activity in vitro, while a mutant (htrabbs198a) does not. however, htrabb and degp have some important differences as ...201323565798
trypanosoma cruzi trans-sialidase initiates a program independent of the transcription factors rorγt and ahr that leads to il-17 production by activated b cells.here we identified b cells as a major source of rapid, innate-like production of interleukin 17 (il-17) in vivo in response to infection with trypanosoma cruzi. il-17(+) b cells had a plasmablast phenotype, outnumbered cells of the th17 subset of helper t cells and were required for an optimal response to this pathogen. with both mouse and human primary b cells, we found that exposure to parasite-derived trans-sialidase in vitro was sufficient to trigger modification of the cell-surface mucin cd ...201323563688
the tracrrna and cas9 families of type ii crispr-cas immunity systems.crispr-cas is a rapidly evolving rna-mediated adaptive immune system that protects bacteria and archaea against mobile genetic elements. the system relies on the activity of short mature crispr rnas (crrnas) that guide cas protein(s) to silence invading nucleic acids. a set of crispr-cas, type ii, requires a trans-activating small rna, tracrrna, for maturation of precursor crrna (pre-crrna) and interference with invading sequences. following co-processing of tracrrna and pre-crrna by rnase iii, ...201323563642
strategy for identification & characterization of bartonella henselae with conventional & molecular methods.bartonella henselae is a fastidious gram-negative bacterium usually causing self limiting infections in immunocompetent individuals but often causes potentially life threatening infection, such as bacillary angiomatosis in immunocompromised patients. both diagnosis of infections and research into molecular mechanisms of pathogenesis have been hindered by lack of appropriate and reliable diagnostic techniques. we undertook this study to standardize methods to characterize b. henselae in clinical ...201323563383
unusual features in organisation of capsular polysaccharide-related genes of c. jejuni strain x.pcr probing of the genome of campylobacter jejuni strain x using conserved capsular polysaccharide (cps)-related genes allowed elucidation of a complete sequence of the respective gene cluster (cps). this is the largest known campylobacter cps cluster (38 kb excluding flanking kps regions), which includes a number of genes not detected in other campylobacter strains. sequence analysis suggests genetic rearrangements both within and outside the cps gene cluster, a mechanism which may be responsib ...201323562723
efficacy of oral fecal bacteriotherapy in rhesus macaques (macaca mulatta) with chronic diarrhea.chronic diarrhea remains the principal burden in providing health care for nonhuman primates in biomedical research facilities. although the exact etiology continues to puzzle nonhuman primate clinicians, recent research in humans has shown that restoring the indigenous microbial diversity may be successful in resolving cases of chronic diarrhea when other treatment modalities have failed. the process of restoring this microbial balance, known as fecal bacteriotherapy, uses the complete flora fr ...201323561941
inactivation of the lysr regulator cj1000 of campylobacter jejuni affects host colonization and respiration.transcriptional regulation mediates adaptation of pathogens to environmental stimuli and is important for host colonization. the campylobacter jejuni genome sequence reveals a surprisingly small set of regulators, mostly of unknown function, suggesting an intricate regulatory network. interestingly, c. jejuni lacks the homologues of ubiquitous regulators involved in stress response found in many other gram-negative bacteria. nonetheless, cj1000 is predicted to encode the sole lysr-type regulator ...201323558264
mlst genotypes and antibiotic resistance of campylobacter spp. isolated from poultry in grenada.this study determined whether multilocus sequence types (mlst) of campylobacter from poultry in 2 farms in grenada, west indies, differed by farm, antimicrobial resistance and farm antibiotic use. farm a used fluoroquinolones in the water and farm b used tetracyclines. the e-test was used to determine resistance of isolates to seven antibiotics. pcr of the ipxa gene confirmed species and mlst was used to characterize 38 isolates. all isolates were either c. jejuni or c. coli. farm antibiotic use ...201323555097
pinworm infestation mimicking crohns' disease.we here report a case of a young man who presented to his general practitioner with diarrhea. inflammatory bowel disease was suspected and a colonoscopy showed aphthous lesions suggestive of crohns' disease but biopsies revealed eggs of enterobius vermicularis. when treated for this parasite, his symptoms were alleviated and a followup colonoscopy revealed a normal colon and distal ileum. enterobius vermicularis is the most common parasite worldwide and has been attributed with many different pr ...201323555063
the contribution of arsb to arsenic resistance in campylobacter jejuni.arsenic, a toxic metalloid, exists in the natural environment and its organic form is approved for use as a feed additive for animal production. as a major foodborne pathogen of animal origin, campylobacter is exposed to arsenic selection pressure in the food animal production environments. previous studies showed that campylobacter isolates from poultry were highly resistant to arsenic compounds and a 4-gene operon (containing arsp, arsr, arsc, and acr3) was associated with arsenic resistance i ...201323554953
the microaerophilic microbiota of de-novo paediatric inflammatory bowel disease: the biscuit study.children presenting for the first time with inflammatory bowel disease (ibd) offer a unique opportunity to study aetiological agents before the confounders of treatment. microaerophilic bacteria can exploit the ecological niche of the intestinal epithelium; helicobacter and campylobacter are previously implicated in ibd pathogenesis. we set out to study these and other microaerophilic bacteria in de-novo paediatric ibd.201323554935
antimicrobial resistance and virulence: a successful or deleterious association in the bacterial world?hosts and bacteria have coevolved over millions of years, during which pathogenic bacteria have modified their virulence mechanisms to adapt to host defense systems. although the spread of pathogens has been hindered by the discovery and widespread use of antimicrobial agents, antimicrobial resistance has increased globally. the emergence of resistant bacteria has accelerated in recent years, mainly as a result of increased selective pressure. however, although antimicrobial resistance and bacte ...201323554414
microbiological diagnosis of severe diarrhea in kidney transplant recipients by use of multiplex pcr assays.diarrhea is a frequent complication after kidney transplantation, ascribed to adverse effects of the immunosuppressive therapy in case of negative microbiological examination of the stools. the aim of this study was to improve the microbiological diagnosis by implementing molecular tests. fifty-four severe diarrhea events that occurred in 49 adult kidney transplant recipients from september 2010 to november 2011 were investigated. one or several enteric pathogens were detected in 13 (23%) stool ...201323554205
detection of non-jejuni and -coli campylobacter species from stool specimens with an immunochromatographic antigen detection assay.the stat! campy immunochromatographic assay for campylobacter antigen was compared to culture for 500 clinical stool specimens. antigen was detected in six culture-negative, pcr-positive specimens. c. upsaliensis, a pathogenic species that is traditionally difficult to recover in routine stool cultures, was detected in two of these culture-negative specimens. this study provides evidence that antigen testing may cross-react with at least one additional non-jejuni and -coli campylobacter species ...201323554192
production and evaluation of the utility of novel phage display-derived peptide ligands to salmonella spp. for magnetic separation.the objectives of this study were to produce salmonella-specific peptide ligands by phage display biopanning and evaluate their use for magnetic separation (ms).201323551658
phylum-wide general protein o-glycosylation system of the bacteroidetes.the human gut symbiont bacteroides fragilis has a general protein o-glycosylation system in which numerous extracytoplasmic proteins are glycosylated at a three amino acid motif. in b. fragilis, protein glycosylation is a fundamental and essential property as mutants with protein glycosylation defects have impaired growth and are unable to competitively colonize the mammalian intestine. in this study, we analysed the phenotype of b. fragilis mutants with defective protein glycosylation and found ...201323551589
improvement of karmali agar by addition of polymyxin b for the detection of campylobacter jejuni and c. coli in whole-chicken carcass rinse.the karmali agar was modified by supplementation with a high concentration of polymyxin b. the goal of the study was to evaluate the effect of a high concentration of polymyxin b on the ability and selectivity of the modified karmali agar to isolate campylobacter jejuni and campylobacter coli from whole chicken carcass rinse. a total of 80 whole chickens were rinsed with 400 ml of buffer peptone water. the rinsed samples were incubated with 2× blood-free modified bolton enrichment broth for 48 h ...201323550907
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