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o-antigen and core carbohydrate of vibrio fischeri lipopolysaccharide: composition and analysis of their role in euprymna scolopes light organ colonization.vibrio fischeri exists in a symbiotic relationship with the hawaiian bobtail squid, euprymna scolopes, where the squid provides a home for the bacteria, and the bacteria in turn provide camouflage that helps protect the squid from night-time predators. like other gram-negative organisms, v. fischeri expresses lipopolysaccharide (lps) on its cell surface. the structure of the o-antigen and the core components of the lps and their possible role in colonization of the squid have not previously been ...201222247546
biology and pathogenesis of acanthamoeba.acanthamoeba is a free-living protist pathogen, capable of causing a blinding keratitis and fatal granulomatous encephalitis. the factors that contribute to acanthamoeba infections include parasite biology, genetic diversity, environmental spread and host susceptibility, and are highlighted together with potential therapeutic and preventative measures. the use of acanthamoeba in the study of cellular differentiation mechanisms, motility and phagocytosis, bacterial pathogenesis and evolutionary p ...201222229971
identification of gene networks and pathways associated with guillain-barré syndrome.the underlying change of gene network expression of guillain-barré syndrome (gbs) remains elusive. we sought to identify gbs-associated gene networks and signaling pathways by analyzing the transcriptional profile of leukocytes in the patients with gbs.201222253732
crystal structure of jlpa, a surface-exposed lipoprotein adhesin of campylobacter jejuni.the campylobacter jejuni jlpa protein is a surface-exposed lipoprotein that was discovered as an adhesin promoting interaction with host epithelium cells, an early critical step in the pathogenesis of c. jejuni disease. increasing evidence ascertained that jlpa is antigenic, indicating a role of jlpa in immune response during the infectious process. here, we report the crystal structure of jlpa at 2.7å resolution, revealing a catcher's mitt shaped unclosed half β-barrel. although the apparent ar ...201222245776
siglecs and immune regulation.sialic acid-binding ig-like lectins, or siglecs, vary in their specificity for sialic acid-containing ligands and are mainly expressed by cells of the immune system. many siglecs are inhibitory receptors expressed in innate immune cells that regulate inflammation mediated by damage-associated and pathogen-associated molecular patterns (damps and pamps). this family also includes molecules involved in adhesion and phagocytosis and receptors that can associate with the itam-containing dap12 adapto ...201222224769
leukocyte inflammatory responses provoked by pneumococcal sialidase.cell surface expression of sialic acid has been reported to decrease during immune cell activation, but the significance and regulation of this phenomenon are still being investigated. the major human bacterial pathogen streptococcus pneumoniae causes pneumonia, sepsis and meningitis, often accompanied by strong inflammatory responses. s. pneumoniae expresses a sialidase (nana) that contributes to mucosal colonization, platelet clearance, and blood-brain barrier penetration. using wild-type and ...201222215570
imaging the glycome in living systems.the glycome, the full complement of glycans that cells produce, is an attractive target for molecular imaging. imaging of the glycome in living systems has recently been enabled via bioorthogonal chemical reporter-based approaches. in this chapter, we describe two approaches to introduce bioorthogonal chemical reporters (tags) onto cell surface fucosylated glycans and glycans bearing lacnac disaccharides, respectively. the tagged glycans can then be conjugated to imaging probes via bioorthogonal ...201222289465
immunity to ricin: fundamental insights into toxin-antibody interactions.ricin toxin is an extraordinarily potent inducer of cell death and inflammation. ricin is also a potent provocateur of the humoral immune system, eliciting a mixture of neutralizing, non-neutralizing and even toxin-enhancing antibodies. the characterization of dozens of monoclonal antibodies (mabs) against the toxin's enzymatic (rta) and binding (rtb) subunits has begun to reveal fundamental insights into the underlying mechanisms by which antibodies neutralize (or fail to neutralize) ricin in s ...201222113742
detection and species identification of campylobacter in stool samples of children and animals from vellore, south india.campylobacter spp. are an important cause of bacterial gastroenteritis frequently isolated from animal, poultry and environmental samples. in this study, we investigated the zoonotic potential of campylobacter spp. by comparing prevalence rates and species in 394 children with diarrhoea and 652 animals in vellore using pcr-based tools. eighteen children (4.5%) had campylobacteriosis, a majority of whom had co-pathogens (15/18) and most were infected with campylobacter jejuni (16/18). a few c. co ...201222361767
ferret thoracic anatomy by 2-deoxy-2-(18f)fluoro-d-glucose (18f-fdg) positron emission tomography/computed tomography (18f-fdg pet/ct) imaging.the domestic ferret (mustela putorius furo) has been a long-standing animal model used in the evaluation and treatment of human diseases. molecular imaging techniques such as 2-deoxy-2-((18)f)fluoro-d-glucose ((18)f-fdg) positron emission tomography (pet) would be an invaluable method of tracking disease in vivo, but this technique has not been reported in the literature. thus, the aim of this study was to establish baseline imaging characteristics of pet/computed tomography (ct) with (18)f-fdg ...201223382267
recent developments in the interactions between caveolin and pathogens.the role of caveolin and caveolae in the pathogenesis of infection has only recently been appreciated. in this chapter, we have highlighted some important new data on the role of caveolin in infections due to bacteria, viruses and fungi but with particular emphasis on the protozoan parasites leishmania spp., trypanosoma cruzi and toxoplasma gondii. this is a continuing area of research and the final chapter has not been written on this topic.201222411314
in silico analysis of sequenced strains of clostridium difficile reveals a related set of conjugative transposons carrying a variety of accessory genes.the human gut pathogen clostridium difficile contains many conjugative transposons that have an array of accessory genes. in the current study, recently sequenced genomes were analyzed to identify new putative conjugative transposons. eleven new elements in 5 c. difficile strains were identified and all had a similar structure to the previously described elements ctn1, ctn5 and ctn7 in c. difficile strain 630. each element identified did however contain a new set of accessory genes compared with ...201222754747
surface-immobilization of chromatographically purified bacteriophages for the optimized capture of bacteria.bacteriophages offer interesting alternatives to antibodies for the specific capture and detection of pathogenic bacteria onto biosensing surfaces. procedures for the optimal chemical immobilization of lytic bacteriophages onto surfaces are presented. more specifically, the removal of lysate contaminants from bacteriophage suspensions by size exclusion chromatography significantly increases the resultant planar surface density of immobilized bacteriophages. e. coli t4 and salmonella enterica ser ...201222666653
substrate channeling in proline metabolism.proline metabolism is an important pathway that has relevance in several cellular functions such as redox balance, apoptosis, and cell survival. results from different groups have indicated that substrate channeling of proline metabolic intermediates may be a critical mechanism. one intermediate is pyrroline-5-carboxylate (p5c), which upon hydrolysis opens to glutamic semialdehyde (gsa). recent structural and kinetic evidence indicate substrate channeling of p5c/gsa occurs in the proline catabol ...201222201749
showers, sweating and suing: legionnaires' disease and 'new' infections in britain, 1977-90.legionnaires' disease is now routinely discussed as an 'emerging infectious disease' (eid) and is said to be one of the earliest such diseases to be recognised. it first appeared in 1976 and its cause was identified in 1977, the same year that ebola fever, hantaan virus and campylobacter jejuni arrived. the designation of legionnaires' disease as an eid was retrospective; it was not and could not be otherwise as the category only gained currency in the early 1990s. in this article we reflect on ...201223752984
familial guillain-barré syndrome: first indian report.guillain-barré syndrome (gbs) is the commonest acute immune-mediated peripheral neuropathy. specific human leukocyte antigen types have been found in patients with axonal and demyelinating subtypes of gbs suggesting genetic susceptibility in the generation of gbs. however, familial occurrence of gbs is rare and 42 patients from 20 families have been reported. majority of them are from european countries and two families have been documented from asian countries, while none have been reported fro ...201222412273
authors' reply. 201222346219
separating significant matches from spurious matches in dna sequences.word matches are widely used to compare genomic sequences. complete genome alignment methods often rely on the use of matches as anchors for building their alignments, and various alignment-free approaches that characterize similarities between large sequences are based on word matches. among matches that are retrieved from the comparison of two genomic sequences, a part of them may correspond to spurious matches (sms), which are matches obtained by chance rather than by homologous relationships ...201222149632
a review of antibiotic use in food animals: perspective, policy, and potential.antibiotic use plays a major role in the emerging public health crisis of antibiotic resistance. although the majority of antibiotic use occurs in agricultural settings, relatively little attention has been paid to how antibiotic use in farm animals contributes to the overall problem of antibiotic resistance. the aim of this review is to summarize literature on the role of antibiotics in the development of resistance and its risk to human health. we searched multiple databases to identify major ...201222298919
progressive genome-wide introgression in agricultural campylobacter coli.hybridization between distantly related organisms can facilitate rapid adaptation to novel environments, but is potentially constrained by epistatic fitness interactions among cell components. the zoonotic pathogens campylobacter coli and c. jejuni differ from each other by around 15% at the nucleotide level, corresponding to an average of nearly 40 amino acids per protein-coding gene. using whole genome sequencing, we show that a single c. coli lineage, which has successfully colonized an agric ...201223279096
progressive genome-wide introgression in agricultural campylobacter coli.hybridization between distantly related organisms can facilitate rapid adaptation to novel environments, but is potentially constrained by epistatic fitness interactions among cell components. the zoonotic pathogens campylobacter coli and c. jejuni differ from each other by around 15% at the nucleotide level, corresponding to an average of nearly 40 amino acids per protein-coding gene. using whole genome sequencing, we show that a single c. coli lineage, which has successfully colonized an agric ...201223279096
diagnostic microbiologic methods in the gems-1 case/control study.to understand the etiology of moderate-to-severe diarrhea among children in high mortality areas of sub-saharan africa and south asia, we performed a comprehensive case/control study of children aged <5 years at 7 sites. each site employed an identical case/control study design and each utilized a uniform comprehensive set of microbiological assays to identify the likely bacterial, viral and protozoal etiologies. the selected assays effected a balanced consideration of cost, robustness and perfo ...201223169941
investigation of motility and biofilm formation by intestinal campylobacter concisus strains.motility helps many pathogens swim through the highly viscous intestinal mucus. given the differing outcomes of campylobacter concisus infection, the motility of eight c. concisus strains isolated from patients with crohn's disease (n=3), acute (n=3) and chronic (n=1) gastroenteritis and a healthy control (n=1) were compared. following growth on solid or liquid media the eight strains formed two groups; however, the type of growth medium did not affect motility. in contrast, following growth in ...201223241133
evaluation of the positive predictive value of a rapid immunochromatographic test to detect campylobacter in stools.the recently developed rapid immunochromatographic tests (ict) have the potential to provide a quick and easy diagnosis of campylobacter enteritis in comparison to culture. in a previous study we found them sensitive but lacking in specificity. the aim of the present study was to focus on the problem of specificity and determine the positive predictive value (ppv) of a positive result of the immunocard stat! campy (meridian bioscience, cincinnati, oh, usa). for this purpose, the stools positive ...201223206554
bioluminescent enzyme immunoassay for the detection of norovirus capsid antigen.an ultrasensitive and fully automated bioluminescent enzyme immunoassay (bleia) was developed for the detection of norovirus (nv) capsid antigen. in the evaluation tests with recombinant virus-like particles, the bleia demonstrated broad reactivity against several nv genotypes (genotypes 1, 3, 4, 7, 8, and 12 in genogroup i [gi] and genotypes 1, 2, 3, 4, 5, 6, 12, and 13 in gii), a wide dose-response range from 0.25 pg/ml to 10,000 pg/ml, and good reproducibility with low coefficients of variati ...201223081816
chromosomal tet(o)-harboring regions in campylobacter coli isolates from turkeys and swine.in turkey-derived campylobacter coli isolates of a unique lineage (cluster ii), the tetracycline resistance determinant tet(o) was chromosomal and was part of a gene cassette (transposon) interrupting a campylobacter jejuni-associated putative citrate transporter gene. in contrast, the swine-derived c. coli strain 6461 harbored a chromosomal tet(o) in a different genomic location.201223023744
association of campylobacter upsaliensis with persistent bloody diarrhea.campylobacter upsaliensis is a zoonotic, emerging pathogen that is not readily recovered in traditional stool culture. this case represents the first report of persistent bloody diarrhea with c. upsaliensis that was confirmed by filtration culture, pcr, and sequencing.201222915607
identification of cj1051c as a major determinant for the restriction barrier of campylobacter jejuni strain nctc11168.campylobacter jejuni is a leading cause of human diarrheal illness in the world, and research on it has benefitted greatly by the completion of several genome sequences and the development of molecular biology tools. however, many hurdles remain for a full understanding of this unique bacterial pathogen. one of the most commonly used strains for genetic work with c. jejuni is nctc11168. while this strain is readily transformable with dna for genomic recombination, transformation with plasmids is ...201222923403
prevalence and antimicrobial resistance of thermophilic campylobacter isolated from chicken in côte d'ivoire.thermophilic campylobacters are major causes of gastroenteritis in human. the main risk factor of infection is consumption of contaminated or by cross-contaminated poultry meat. in côte d'ivoire, gastroenteritis is usually observed but no case of human campylobacteriosis has been formally reported to date. the aims of this study were to determine prevalence and antimicrobial resistance of campylobacter jejuni and campylobacter coli isolated from chickens ceaca in commercial slaughter in abidjan. ...201223133454
bacterial toxin modulation of the eukaryotic cell cycle: are all cytolethal distending toxins created equally?the cytolethal distending toxins (cdts) comprise a family of intracellular-acting bacterial protein toxins whose actions upon eukaryotic cells result in several consequences, the most characteristic of which is the induction of g(2)/m cell cycle arrest. most cdts are hetero-tripartite assemblies of cdta, cdtb, and cdtc, with cdtb required for cdt-mediated cell cycle arrest. several lines of evidence indicate that cdta and cdtc are required for the optimal intracellular activity of cdtb, although ...201223061054
a longitudinal 6-year study of the molecular epidemiology of clinical campylobacter isolates in oxfordshire, united kingdom.temporal and seasonal trends in campylobacter genotypes causing human gastroenteritis were investigated in a 6-year study of 3,300 recent isolates from oxfordshire, united kingdom. genotypes (sequence types [st]) were defined using multilocus sequence typing and assigned to a clonal complex (a cluster of related strains that share four or more identical alleles with a previously defined central genotype). a previously undescribed clonal complex (st-464) was identified which, together with st-42, ...201222814466
identification of a novel genomic island conferring resistance to multiple aminoglycoside antibiotics in campylobacter coli.historically, the incidence of gentamicin resistance in campylobacter has been very low, but recent studies reported a high prevalence of gentamicin-resistant campylobacter isolated from food-producing animals in china. the reason for the high prevalence was unknown and was addressed in this study. pcr screening identified aminoglycoside resistance genes apha-3 and apha-7 and the aade-sat4-apha-3 cluster among 41 campylobacter isolates from broiler chickens. importantly, a novel genomic island c ...201222869568
case-control study of the etiology of infant diarrheal disease in 14 districts in madagascar.acute diarrhea is a major cause of childhood morbidity and mortality worldwide. its microbiological causes and clinico-epidemiological aspects were examined during the rainy seasons from 2008 to 2009 in 14 districts in madagascar.201223028555
a convenient and robust in vivo reporter system to monitor gene expression in the human pathogen helicobacter pylori.thirty years of intensive research have significantly contributed to our understanding of helicobacter pylori biology and pathogenesis. however, the lack of convenient genetic tools, in particular the limited effectiveness of available reporter systems, has notably limited the toolbox for fundamental and applied studies. here, we report the construction of a bioluminescent h. pylori reporter system based on the photorhabdus luminescens luxcdabe cassette. the system is constituted of a promoterle ...201222773640
outcome of infection of c57bl/6 il-10(-/-) mice with campylobacter jejuni strains is correlated with genome content of open reading frames up- and down-regulated in vivo.human campylobacter jejuni infection can result in an asymptomatic carrier state, watery or bloody diarrhea, bacteremia, meningitis, or autoimmune neurological sequelae. infection outcomes of c57bl/6 il-10(-/-) mice orally infected with twenty-two phylogenetically diverse c. jejuni strains were evaluated to correlate colonization and disease phenotypes with genetic composition of the strains. variation between strains was observed in colonization, timing of development of clinical signs, and occ ...201222960579
outcome of infection of c57bl/6 il-10(-/-) mice with campylobacter jejuni strains is correlated with genome content of open reading frames up- and down-regulated in vivo.human campylobacter jejuni infection can result in an asymptomatic carrier state, watery or bloody diarrhea, bacteremia, meningitis, or autoimmune neurological sequelae. infection outcomes of c57bl/6 il-10(-/-) mice orally infected with twenty-two phylogenetically diverse c. jejuni strains were evaluated to correlate colonization and disease phenotypes with genetic composition of the strains. variation between strains was observed in colonization, timing of development of clinical signs, and occ ...201222960579
analysis of evolutionary patterns of genes in campylobacter jejuni and c. coli. 201222929701
campylobacter antimicrobial resistance in peru: a ten-year observational study.campylobacter jejuni and campylobacter coli are food-borne pathogens of great importance and feature prominently in the etiology of developing world enteritis and travellers' diarrhoea. increasing antimicrobial resistant campylobacter prevalence has been described globally, yet data from peru is limited. our objective was to describe the prevalence trends of fluoroquinolone and macrolide-resistant c. jejuni and c. coli stool isolates from three regions in peru over a ten-year period.201222898609
acid stress response and protein induction in campylobacter jejuni isolates with different acid tolerance.during the transmission route from poultry to the human host, the major foodborne pathogen c. jejuni may experience many types of stresses, including low ph caused by different acids. however, not all strains are equally sensitive to the stresses. the aim of this study was to investigate the response to acid stress of three sequenced c. jejuni strains with different acid tolerances using hcl and acetic acid.201222889088
the complete genome sequence of bacteriophage cp21 reveals modular shuffling in campylobacter group ii phages.campylobacter group ii phages described so far share a high degree of sequence similarity. we report the 182,833-bp genomic sequence of the closely related group ii phage cp21 and show that it has a completely different genomic organization. as in other group ii phages, the cp21 genome is composed of large modules separated by long dna repeat regions which obviously trigger recombination and modular shuffling.201222843857
ischaemic colitis associated with oral contraceptive and bisacodyl use.a woman with a history of hip replacement presented 3 days prior to revision of the hip with abdominal pain, diarrhoea and haematochezia. these symptoms began 6 h after she began taking bisacodyl in preparation for her upcoming surgery. she was on low-dose estradiol for hormone replacement therapy (hrt). subsequent colonoscopy and biopsies were consistent with acute colonic ischaemia (ci). she was treated with intravenous fluids and antibiotics and discharged and told to stop hrt and bisacodyl. ...201222843752
guillain-barré syndrome and anti-ganglioside antibodies: a clinician-scientist's journey.guillain-barré syndrome (gbs) is the most frequent cause of acute flaccid paralysis. having seen my first gbs patient in 1989, i have since then dedicated my time in research towards understanding the pathogenesis of gbs. along with several colleagues, we identified igg autoantibodies against ganglioside gm1 in two patients with gbs subsequent to campylobacter jejuni enteritis. we proceeded to demonstrate molecular mimicry between gm1 and bacterial lipo-oligosaccharide of c. jejuni isolated from ...201222850724
restricted gene flow among hospital subpopulations of enterococcus faecium.enterococcus faecium has recently emerged as an important multiresistant nosocomial pathogen. defining population structure in this species is required to provide insight into the existence, distribution, and dynamics of specific multiresistant or pathogenic lineages in particular environments, like the hospital. here, we probe the population structure of e. faecium using bayesian-based population genetic modeling implemented in bayesian analysis of population structure (baps) software. the anal ...201222807567
campylobacter epidemiology: a descriptive study reviewing 1 million cases in england and wales between 1989 and 2011.to review campylobacter cases in england and wales over 2 decades and examine the main factors/mechanisms driving the changing epidemiology.201222798256
estimating the relative roles of recombination and point mutation in the generation of single locus variants in campylobacter jejuni and campylobacter coli.single locus variants (slvs) are bacterial sequence types that differ at only one of the seven canonical multilocus sequence typing (mlst) loci. estimating the relative roles of recombination and point mutation in the generation of new alleles that lead to slvs is helpful in understanding how organisms evolve. the relative rates of recombination and mutation for campylobacter jejuni and campylobacter coli were estimated at seven different housekeeping loci from publically available mlst data. th ...201222767048
nutraceutical values of natural honey and its contribution to human health and wealth.the use of natural honey (nh) as a nutraceutical agent is associated with nutritional benefits and therapeutic promises. nh is widely accepted as food and medicine by all generations, traditions and civilizations, both ancient and modern. the nutritional profiles, including its use in infant and children feeding reported in different literatures as well as health indices and biomarkers observed by various researchers are illustrated in this manuscript. the review documents folk medicine, experim ...201222716101
detection of shiga toxin-producing escherichia coli by sandwich enzyme-linked immunosorbent assay using chicken egg yolk igy antibodies.enterohemorrhagic escherichia coli (ehec), a subset of shiga toxin producing e. coli (stec) is associated with a spectrum of diseases that includes diarrhea, hemorrhagic colitis and a life-threatening hemolytic-uremic syndrome (hus). regardless of serotype, shiga toxins (stx1 and/or stx2) are uniformly expressed by all ehec, and so exploitable targets for laboratory diagnosis of these pathogens. in this study, a sandwich elisa for determination of shiga toxin (stx) was developed using anti-stx2b ...201222919675
development and evaluation of a genus-specific, probe-based, internal-process-controlled real-time pcr assay for sensitive and specific detection of blastocystis spp.blastocystis is a common intestinal parasite of unsettled clinical significance, which is not easily detected by standard parasitological methods. the genus comprises at least 13 subtypes (sts) (which likely represent separate species), 9 of which have been found in humans. recent data indicate that at least one of the subtypes is associated with intestinal disease. a quantitative taqman 5' nuclease real-time pcr (taqman pcr) including an internal process control (ipc) was developed for the dete ...201222422846
development of a novel genus-specific real-time pcr assay for detection and differentiation of bartonella species and genotypes.the genus bartonella includes numerous species with varied host associations, including several that infect humans. development of a molecular diagnostic method capable of detecting the diverse repertoire of bartonella species while maintaining genus specificity has been a challenge. we developed a novel real-time pcr assay targeting a 301-bp region of the ssra gene of bartonella and demonstrated specific amplification in over 30 bartonella species, subspecies, and strains. subsequent analysis o ...201222378904
characterization of the structurally diverse n-linked glycans of campylobacter species.the gram-negative bacterium campylobacter jejuni encodes an extensively characterized n-linked protein glycosylation system that modifies many surface proteins with a heptasaccharide glycan. in c. jejuni, the genes that encode the enzymes required for glycan biosynthesis and transfer to protein are located at a single pgl gene locus. similar loci are also present in the genome sequences of all other campylobacter species, although variations in gene content and organization are evident. in this ...201222389484
a gene-by-gene approach to bacterial population genomics: whole genome mlst of campylobacter.campylobacteriosis remains a major human public health problem world-wide. genetic analyses of campylobacter isolates, and particularly molecular epidemiology, have been central to the study of this disease, particularly the characterization of campylobacter genotypes isolated from human infection, farm animals, and retail food. these studies have demonstrated that campylobacter populations are highly structured, with distinct genotypes associated with particular wild or domestic animal sources, ...201224704917
xer recombinase and genome integrity in helicobacter pylori, a pathogen without topoisomerase iv.in the model organism e. coli, recombination mediated by the related xerc and xerd recombinases complexed with the ftsk translocase at specialized dif sites, resolves dimeric chromosomes into free monomers to allow efficient chromosome segregation at cell division. computational genome analysis of helicobacter pylori, a slow growing gastric pathogen, identified just one chromosomal xer gene (xerh) and its cognate dif site (difh). here we show that recombination between directly repeated difh sit ...201222511919
longitudinal study of the persistence of antimicrobial-resistant campylobacter strains in distinct swine production systems on farms, at slaughter, and in the environment.the objectives of this study were to compare and characterize the prevalence of antimicrobial-resistant (ar) campylobacter in conventional and antimicrobial-free (abf) production systems on farms, at slaughter, and in the environment. fecal and environmental samples were collected from abf farms (pigs, 1,239; environment, 797) and conventional farms (pigs, 1,650; environment, 1,325). at slaughter, we collected samples from carcasses, including postevisceration swabs, postchill swabs, and mesente ...201222307299
molecular detection of campylobacter jejuni as a cause of culture-negative spondylodiscitis.spondylodiscitis caused by campylobacter species is a rare disease which is most often caused by campylobacter fetus. we report a case of culture-negative spondylodiscitis and a psoas abscess due to campylobacter jejuni in a 68-year-old woman, as revealed by 16s rrna gene and campylobacter-specific pcrs from biopsied tissue.201222259199
comparison of the microflex lt and vitek ms systems for routine identification of bacteria by matrix-assisted laser desorption ionization-time of flight mass spectrometry.this study compared the performance of three matrix-assisted laser desorption ionization-time of flight mass spectrometry systems: microflex lt (bruker daltonics, bremen, germany), vitek ms ruo (axima assurance-saramis database; biomérieux, marcy l'etoile, france), and vitek ms ivd (biomérieux). a total of 1,129 isolates, including 1,003 routine isolates, 73 anaerobes, and 53 bacterial enteropathogens, were tested on the microflex lt and axima assurance devices. the spectra were analyzed using t ...201222322345
campylobacter bacteremia: a rare and under-reported event?bacteria belonging to the species campylobacter are the most common cause of bacterial diarrhoea in humans. the clinical phenotype associated with campylobacter infections ranges from asymptomatic conditions to severe colitis and bacteremia. in susceptible patients, campylobacter infections are associated with significant morbidity and mortality, with both host factors and bacterial factors being involved in the pathogenesis of bacteremia. in the host, age, gender and immune-compromising conditi ...201224611124
current concepts in laboratory testing to guide antimicrobial therapy.antimicrobial susceptibility testing (ast) is indicated for pathogens contributing to an infectious process that warrants antimicrobial therapy if susceptibility to antimicrobials cannot be predicted reliably based on knowledge of their identity. such tests are most frequently used when the etiologic agents are members of species capable of demonstrating resistance to commonly prescribed antibiotics. some organisms have predictable susceptibility to antimicrobial agents (ie, streptococcus pyogen ...201222386185
characterization of protein glycosylation in francisella tularensis subsp. holarctica: identification of a novel glycosylated lipoprotein required for virulence.fth_0069 is a previously uncharacterized strongly immunoreactive protein that has been proposed to be a novel virulence factor in francisella tularensis. here, the glycan structure modifying two c-terminal peptides of fth_0069 was identified utilizing high resolution, high mass accuracy mass spectrometry, combined with in-source cid tandem ms experiments. the glycan observed at m/z 1156 was determined to be a hexasaccharide, consisting of two hexoses, three n-acetylhexosamines, and an unknown mo ...201222361235
development and comparison of a real-time pcr assay for detection of dichelobacter nodosus with culturing and conventional pcr: harmonisation between three laboratories.ovine footrot is a contagious disease with worldwide occurrence in sheep. the main causative agent is the fastidious bacterium dichelobacter nodosus. in scandinavia, footrot was first diagnosed in sweden in 2004 and later also in norway and denmark. clinical examination of sheep feet is fundamental to diagnosis of footrot, but d. nodosus should also be detected to confirm the diagnosis. pcr-based detection using conventional pcr has been used at our institutes, but the method was laborious and t ...201222293440
the genome and proteome of a campylobacter coli bacteriophage vb_ccom-ibb_35 reveal unusual features.campylobacter is the leading cause of foodborne diseases worldwide. bacteriophages (phages) are naturally occurring predators of bacteria, ubiquitous in the environment, with high host specificity and thus considered an appealing option to control bacterial pathogens. nevertheless for an effective use of phages as antimicrobial agents, it is important to understand phage biology which renders crucial the analysis of phage genomes and proteomes. the lack of sequence data from campylobacter phages ...201222284308
leptospiral outer membrane protein microarray, a novel approach to identification of host ligand-binding proteins.leptospirosis is a zoonosis with worldwide distribution caused by pathogenic spirochetes belonging to the genus leptospira. the leptospiral life cycle involves transmission via freshwater and colonization of the renal tubules of their reservoir hosts. infection requires adherence to cell surfaces and extracellular matrix components of host tissues. these host-pathogen interactions involve outer membrane proteins (omps) expressed on the bacterial surface. in this study, we developed an leptospira ...201222961849
automatic assignment of prokaryotic genes to functional categories using literature profiling.in the last years, there was an exponential increase in the number of publicly available genomes. once finished, most genome projects lack financial support to review annotations. a few of these gene annotations are based on a combination of bioinformatics evidence, however, in most cases, annotations are based solely on sequence similarity to a previously known gene, which was most probably annotated in the same way. as a result, a large number of predicted genes remain unassigned to any functi ...201223077617
mathematical modeling and comparison of protein size distribution in different plant, animal, fungal and microbial species reveals a negative correlation between protein size and protein number, thus providing insight into the evolution of proteomes.the sizes of proteins are relevant to their biochemical structure and for their biological function. the statistical distribution of protein lengths across a diverse set of taxa can provide hints about the evolution of proteomes.201222296664
molecular mechanisms and biological role of campylobacter jejuni attachment to host cells.adhesion to host cells is an important step in pathogenesis of campylobacter jejuni, which is the most prevalent bacterial cause of human gastroenteritis worldwide. in contrast to other bacteria such as e. coli and salmonella, adherence of c. jejuni is not mediated by fimbria or pili. a number of c. jejuni adhesion-related factors have been described. however, the results obtained by different researchers in different laboratories are often contradictory and inconclusive, with only some of the f ...201224611119
rodents on pig and chicken farms - a potential threat to human and animal health.rodents can cause major problems through spreading various diseases to animals and humans. the two main species of rodents most commonly found on farms around the world are the house mouse (mus musculus) and the brown rat (rattus norvegicus). both species are omnivorous and can breed year-round under favourable conditions. this review describes the occurrence of pathogens in rodents on specialist pig and chicken farms, which are usually closed units with a high level of bio-security. however, wi ...201222957130
complete 6-deoxy-d-altro-heptose biosynthesis pathway from campylobacter jejuni: more complex than anticipated.the campylobacter jejuni capsule is important for colonization and virulence in various infection models. in most strains, the capsule includes a modified heptose whose biological role and biosynthetic pathway are unknown. to decipher the biosynthesis pathway for the 6-deoxy-d-altro-heptose of strain 81-176, we previously showed that the 4,6-dehydratase wcbk and the reductase wcag generated gdp-6-deoxy-d-manno-heptose, but the c3 epimerase necessary to form gdp-6-deoxy-d-altro-heptose was not id ...201222787156
performances of the vitek ms matrix-assisted laser desorption ionization-time of flight mass spectrometry system for rapid identification of bacteria in routine clinical microbiology.rapid and cost-effective matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms)-based systems will replace conventional phenotypic methods for routine identification of bacteria. we report here the first evaluation of the new maldi-tof ms-based vitek ms system in a large clinical microbiology laboratory. this system uses an original spectrum classifier algorithm and a specific database designed for the identification of clinically relevant species. we have te ...201222593596
dprb facilitates inter- and intragenomic recombination in helicobacter pylori.for naturally competent microorganisms, such as helicobacter pylori, the steps that permit recombination of exogenous dna are not fully understood. immediately downstream of an h. pylori gene (dpra) that facilitates high-frequency natural transformation is hp0334 (dprb), annotated to be a putative holliday junction resolvase (hjr). we showed that the hp0334 (dprb) gene product facilitates high-frequency natural transformation. we determined the physiologic roles of dprb by genetic analyses. dprb ...201222609923
toll-like receptor 4 mediates intrauterine growth restriction after systemic campylobacter rectus infection in mice.campylobacter rectus is associated with fetal exposure and low birthweight in humans. c. rectus also invades placental tissues and induces fetal intrauterine growth restriction (iugr) in mice, along with overexpression of toll-like receptors (tlr4), suggesting that tlr4 may mediate placental immunity and iugr in mice. to test this hypothesis we examined the effect of in vitro tlr4 neutralization on trophoblastic proinflammatory activity and studied the iugr phenotype in a congenic tlr4-mutant mo ...201222958386
investigation of the enteric pathogenic potential of oral campylobacter concisus strains isolated from patients with inflammatory bowel disease.campylobacter concisus, a bacterium colonizing the human oral cavity, has been shown to be associated with inflammatory bowel disease (ibd). this study investigated if patients with ibd are colonized with specific oral c. concisus strains that have potential to cause enteric diseases.201222666490
novel functions for glycosyltransferases jhp0562 and galt in lewis antigen synthesis and variation in helicobacter pylori.lewis (le) antigens are fucosylated oligosaccharides present in the helicobacter pylori lipopolysaccharide. expression of these antigens is believed to be important for h. pylori colonization, since le antigens also are expressed on the gastric epithelia in humans. a galactosyltransferase encoded by β-(1,3)galt is essential for production of type 1 (le(a) and le(b)) antigens. the upstream gene jhp0562, which is present in many but not all h. pylori strains, is homologous to β-(1,3)galt but is of ...201222290141
putative mechanisms and biological role of coccoid form formation in campylobacter jejuni.in certain conditions campylobacter jejuni cells are capable of changing their cell shape from a typically spiral to a coccoid form (cf). by similarity to other bacteria, the latter was initially considered to be a viable but non-culturable form capable of survival in unfavourable conditions. however, subsequent studies with c. jejuni and closely related bacteria helicobacter pylori suggested that cf represents a non-viable, degenerative form. until now, the issue on whether the cf of c. jejuni ...201224611120
[role of infectious agents in the emergence of malignant tumors].according to the data of the international agency for research on cancer (iarc), at least 6 virus species (hpv, ebv, hhv-8/kshv, htlv-1, hbv, hcv), 4 helminthes species (schistosoma haematobium and japonicum, opisthorchis viverrini, clonorchis sinensis) and i bacterium species (helicobacter pylori) have been proved to be capable of causing the development of cancer. the analysis of the data available shows that merkel cell polyomavirus (mcv), herpes simplex virus (hsv), john cunningham polyomavi ...201223163048
acute diarrhea among military recruits.there is a considerable amount of speculations concerning the presence of symptoms mainly diarrhea in various bacterial and parasitic infections. among a youth group with acute diarrhea, many bacterial and parasitic diseases were detected. the bacterial causes were campylobacter jejuni, shigella sp. entero-toxigenic, escherichia coli, salmonella sp. and aeromonas hydrophila. the parasitic causes were cryptosporidium parvum, entamoeba histolytica, giardia lamblia and strongyloides stercoralis. ma ...201223214210
identification of the first known inhibitors of o-acetylpeptidoglycan esterase: a potential new antibacterial target.the o-acetylation of peptidoglycan (pg) is now known to occur in 53 species, including numerous human pathogens such as, staphylococcus aureus, bacillus anthracis, species of enterococcus, campylobacter jejuni, helicobacter pylori, neisseria gonorrhoeae and n. meningitidis. this modification, which occurs at the c-6 hydroxyl of n-acetylmuramoyl residues within pg, serves to regulate autolytic activity during pg metabolism and contributes to pathogenesis and persistence within a host. o-acetylpep ...201222351512
molecular characterization and genotypic antimicrobial resistance analysis of campylobacter jejuni and campylobacter coli isolated from broiler flocks in northern italy.genetic variability and genotypic antimicrobial resistance (amr) of campylobacter jejuni and campylobacter coli from commercial broiler farms were investigated in this study. campylobacter isolates were genetically characterized by random amplified polymorphic dna (rapd)-polymerase chain reaction (pcr) and flaa-svr and flab-svr sequence-based typing. eight rapd types were identified in c. jejuni and three in c. coli, while 16 fla profiles were detected among all isolates. further, 13 flaa-svr an ...201223237371
screening for lactic acid bacteria capable of inhibiting campylobacter jejuni in in vitro simulations of the broiler chicken caecal environment.thermotolerant campylobacter spp., specifically campylobacter jejuni and campylobacter coli, are the most common bacterial causes of human gastroenteritis in developed countries. consumption of improperly prepared poultry products and cross contamination are among the main causes of human campylobacteriosis. the aim of this study was to identify lactic acid bacterial (lab) strains capable of inhibiting c. jejuni growth in initial in vitro trials ('spot-on-lawn' method), as well as in batch ferme ...201223234730
comparative genotypic and antimicrobial susceptibility analysis of zoonotic campylobacter species isolated from broilers in a nationwide survey, portugal.campylobacter is a major cause of human foodborne disease worldwide and has been associated with the consumption of contaminated poultry. the prevalence of campylobacter species in broiler flocks from more than 200 producers widespread in mainland portugal was assessed in 2008 in response to commission decision 2007/516/ec. campylobacter isolates were obtained from 83.3% of 424 pooled cecal samples, with a higher prevalence of campylobacter coli (61.2%) than campylobacter jejuni (38.8%). restric ...201223212005
antibiotic susceptibility of salmonella, campylobacter coli, and campylobacter jejuni isolated from northern german fattening pigs.this study was conducted to assess the antimicrobial susceptibility rate of salmonella and campylobacter spp. isolated from northern german fattening pigs. from 540 lymph node samples, 16 salmonella typhimurium, 1 salmonella brandenburg, 37 campylobacter coli, and 11 campylobacter jejuni strains were isolated. antibiotic susceptibility testing was carried out by the broth dilution method. the 14 tested antibiotics for salmonella were ampicillin, cefotaxime, ceftazidime, chloramphenicol, ciproflo ...201223043834
antibiotic resistance in bacterial pathogens from retail raw meats and food-producing animals in japan.to determine the prevalence and antimicrobial susceptibility profiles of campylobacter, salmonella, staphylococcus aureus, methicillin-resistant s. aureus (mrsa), and vancomycin-resistant enterococci (vre) in food-producing animals and retail raw meats in japan, raw meat samples as well as food-producing animal feces, cutaneous swabs, and nasal swabs collected from 2004 to 2006 were analyzed. isolation rates of campylobacter jejuni and campylobacter coli, salmonella, and s. aureus were 34.6% (36 ...201223043825
[simple and rapid detection methods for campylobacters].campylobacter jejuni and campylobacter coli have been leading cause of food poisoning in terms of both number of patients and cases in japan. therefore these bacteria are recognized as one of the most important food-borne pathogens. since campylobacters are microaerobic, slow growing, biochemically unreactive, not only it takes some time but also there are several problems regarding isolation and identification of campylobacter spp. we found that cytolethal distending toxin (cdt) genes are ubiqu ...201222894063
short-term and medium-term clinical outcomes of campylobacter concisus infection.there are only sparse data on the short-term and medium-term clinical impacts of campylobacter concisus infection. a clinical study was performed during a 2-year period to determine the clinical manifestations in c. concisus-positive adult patients. a case patient was defined as an adult patient (≥18 years) with a c. concisus-positive stool sample during the study period. clinical data were obtained with use of a questionnaire supplemented with the patients' medical records, if any. the short-te ...201222882347
bacteremia caused by antimicrobial resistant campylobacter species at a medical center in taiwan, 1998-2008.this study was intended to delineate the clinical and microbiological characteristics of patients with bacteremia caused by campylobacter species.201222771419
effects of efflux pump inhibitors on erythromycin, ciprofloxacin, and tetracycline resistance in campylobacter spp. isolates.the aim was to assess the potency of the efflux pump inhibitors (epis) phenylalanine-arginine ß-naphthylamide (paßn) and 1-(1-naphthylmethyl)-piperazine (nmp) and the putative natural epi phenolic (-)-epigallocatechin gallate (egcg) for the reversal of erythromycin, ciprofloxacin, and tetracycline resistance in campylobacter jejuni and campylobacter coli isolates. we investigated target mutations and resistant genes involved in erythromycin and tetracycline resistance and determined the roles of ...201222741576
prevalence of multidrug resistance campylobacter jejuni and campylobacter coli in chickens slaughtered in selected markets, malaysia.the objectives of this study were to determine the occurrence of campylobacter spp. in live chickens sold at wet markets in selangor, malaysia and the multidrug resistance (mdr) profiles of the isolates. cloacal swabs were taken from the chickens before slaughter and their caecal mucosae were swabbed after slaughter. of the 90 chickens examined, 68 (75.6%) were positive for campylobacter. campylobacter were recovered from caecal swabs (53/90) and cloacal swabs (34/90) and campylobacter coli (46 ...201222735845
prevalence of human pathogens and indicators in stormwater runoff in brisbane, australia.elevated numbers of enteric pathogens in the receiving waters following a storm event can be a serious public health concern. the purpose of this study was to conduct a preliminary investigation into the presence of human pathogens of concern in urban stormwater runoff. the involvement of a human sewage as a potential source of contamination was also investigated by using microbial source tracking methods. water samples (20 l) were collected after storm events and during the dry weather from six ...201222572123
incidence and antimicrobial resistance profiling of campylobacter in retail chicken livers and gizzards.campylobacter species are one of the leading causes of foodborne disease in the united states. campylobacter jejuni and campylobacter coli are the two main species that are of concern to human health, and they cause approximately 95% of human infections. the number of studies investigating campylobacter in chicken livers and gizzards is very limited in the literature. the objective of this study was to determine the prevalence of campylobacter jejuni and campylobacter coli in retail chicken live ...201222545960
trend analysis of antimicrobial resistance in campylobacter jejuni and campylobacter coli isolated from belgian pork and poultry meat products using surveillance data of 2004-2009.the purpose of this study was to analyze and compare antimicrobial resistance in campylobacter spp. isolated from pork and poultry carcasses, and pork and poultry meat (at slaughterhouse level, during meat cutting, and at retail) in belgium, using available surveillance data over the period 2004-2009. the susceptibilities of 1724 campylobacter isolates for ampicillin, ciprofloxacin, nalidixic acid, tetracycline, erythromycin, and gentamicin were tested by e-test. gentamicin resistance was low (n ...201222510058
isolation of campylobacter from feral swine (sus scrofa) on the ranch associated with the 2006 escherichia coli o157:h7 spinach outbreak investigation in california.we report the isolation of campylobacter species from the same population of feral swine that was investigated in san benito county, california, during the 2006 spinach-related escherichia coli o157:h7 outbreak. this is the first survey of campylobacter in a free-ranging feral swine population in the united states. campylobacter species were cultured from buccal and rectal-anal swabs, colonic faeces and tonsils using a combination of selective enrichment and antibiotic-free membrane filtration m ...201222405465
involvement of efflux mechanisms in biocide resistance of campylobacter jejuni and campylobacter coli.active efflux has an important role in the antimicrobial resistance of campylobacter jejuni and campylobacter coli. the effects of two putative efflux pump inhibitors (epis), phenylalanine-arginine β-naphthylamide and 1-(1-naphthylmethyl)-piperazine, and the effects of inactivation of the cmeb,cmef and cmer genes on resistance to a broad range of antimicrobials were studied using the broth microdilution method. the antimicrobials tested in c. jejuni and c. coli were the biocides triclosan, benza ...201222361460
campylobacter sequence typing databases: applications and future prospects.human campylobacteriosis, caused by the zoonotic bacteria campylobacter jejuni and campylobacter coli, remains a major cause of gastroenteritis worldwide. for many countries the implementation of effective interventions to reduce the burden of this disease is a high priority. nucleotide sequence-based typing, including multilocus sequence typing (mlst) and antigen gene sequence typing (agst), has provided unified, comprehensive, and portable campylobacter isolate characterization, with curated d ...201222986295
an enhanced technique combining pre-enrichment and passive filtration increases the isolation efficiency of campylobacter jejuni and campylobacter coli from water and animal fecal samples.improved isolation techniques from environmental water and animal samples are vital to understanding campylobacter epidemiology. in this study, the efficiency of selective enrichment in bolton broth (bb) followed by plating on charcoal cefoperazone deoxycholate agar (ccda) (conventional method) was compared with an approach combining bb enrichment and passive filtration (membrane method) adapted from a method previously developed for testing of broiler meat, in the isolation of thermophilic camp ...201222985716
fitness of macrolide resistant campylobacter coli and campylobacter jejuni.the aim of this study was to investigate the fitness of macrolide resistant campylobacter coli and campylobacter jejuni. the in vitro growth, the survival on food matrix, and the in vivo colonization of c. jejuni and c. coli susceptible isolates and their isogenic resistant mutants were studied. in vitro experiments demonstrated that macrolide resistance imposed a fitness cost when the susceptible strains and their isogenic resistant mutants were cultured in competition. when inoculated in food ...201222324770
prevalence, antibiotic resistance and rapd typing of campylobacter species isolated from ducks, their rearing and processing environments in penang, malaysia.we report for the first time on the prevalence, antibiotic resistance and rapd types of campylobacter species in ducks and duck related environmental samples in malaysia. samples were examined by enrichment in bolton broth followed by plating onto modified charcoal cefoperazone deoxycholate agar (mccda) and/or plating directly onto mccda. a total of 643 samples were screened, and the prevalence of campylobacter spp. in samples from different sources ranged from 0% to 85%. the method of isolation ...201222285201
elucidation of colonization time and prevalence of thermophilic campylobacter species during turkey rearing using multiplex polymerase chain reaction.two turkey flocks (male and female) and the environment of their house were investigated for the presence of thermophilic campylobacter. sample dna was extracted directly from fecal material and environmental samples. bacterial identification was done using a modified campylobacter species specific multiplex pcr. the times needed for colonization and prevalence in male and female turkeys were determined independently. all environmental samples collected before restocking were negative in the pcr ...201222252360
susceptibility of campylobacter to high intensity near ultraviolet/visible 395±5nm light and its effectiveness for the decontamination of raw chicken and contact surfaces.campylobacter is an important cause of human gastroenteritis worldwide. chicken meat is frequently contaminated with this organism and is considered to be a significant source of infection. it has been predicted that lowering the numbers of campylobacter on chicken meat can reduce the risk to public health. the aims of the current study were to investigate the susceptibility of campylobacter to high intensity near ultraviolet/visible (nuv-vis) 395±5nm light and to examine its potential for the m ...201223107507
structural characterization of the highly cyclized lantibiotic paenicidin a via a partial desulfurization/reduction strategy.lantibiotics are ribosomally synthesized antimicrobial peptides produced by bacteria that are increasingly of interest for food preservation and possible therapeutic uses. these peptides are extensively post-translationally modified, and are characterized by lanthionine and methyllanthionine thioether cross-links. paenibacillus polymyxa nrrl b-30509 was found to produce polymyxins and tridecaptins, in addition to a novel lantibiotic termed paenicidin a. a bacteriocin termed srcam 602 previously ...201223167271
research considerations for more effective groundwater monitoring.since numerous pathogens occur in feces, water is monitored for fecal contamination using indicator organisms rather than individual pathogens. although this approach is supported by health effects data in recreational waters, it is questionable when used for drinking water. most outbreaks in groundwater occur in systems that have not violated the us epa's maximum contaminant limit (mcl) for total coliforms within 12 months before the outbreak. additionally, environmentally stable viruses and pa ...201223165708
application of ozonated dry ice (aligal™ blue ice) for packaging and transport in the food industry.dry ice is used by meat and poultry processors for temperature reduction during processing and for temperature maintenance during transportation. aligal™ blue ice (abi), which combines the antimicrobial effect of ozone (o(3)) along with the high cooling capacity of dry ice, was investigated for its effect on bacterial reduction in air, in liquid, and on food and glass surfaces. through proprietary means, o(3) was introduced to produce dry ice pellets to a concentration of 20 parts per million (p ...201223163945
quantitative risk assessment of verocytotoxin-producing escherichia coli o157 and campylobacter jejuni related to consumption of raw milk in a province in northern italy.a quantitative risk assessment was developed to describe the risk of campylobacteriosis and hemolytic uremic syndrome (hus) linked to consumption of raw milk sold in vending machines in northern italy. exposure assessment considered the microbiological status of dairy farms, expected milk contamination, storage conditions from bulk tank to home storage, microbial growth during storage, destruction experiments, consumption frequency of raw milk, age of consumers, serving size, and consumption pre ...201223127713
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