Academic literature on the topic 'Helicobacter bilis'

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Journal articles on the topic "Helicobacter bilis"

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Hynes, Sean O., Susann Teneberg, Niamh Roche, and Torkel Wadström. "Glycoconjugate Binding of Gastric and Enterohepatic Helicobacter spp." Infection and Immunity 71, no. 5 (May 2003): 2976–80. http://dx.doi.org/10.1128/iai.71.5.2976-2980.2003.

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ABSTRACT Helicobacter pylori is able to utilize several lectin-like, protein-carbohydrate interactions for binding to mucins, cell surfaces, and extracellular matrix proteins. As determined by hemagglutination assays and binding of radiolabeled bacteria to glycosphingolipids on thin-layer chromatograms, strains of gastric helicobacters and enterohepatic helicobacters, including Helicobacter canis, Helicobacter hepaticus, and Helicobacter bilis, also demonstrated evidence for the presence of lectin-hemagglutinin adhesins. In addition, in H. hepaticus and H. bilis, binding may be sialic acid dependent. The presence or absence and differences in the levels of activity of lectin adhesins may reflect the species' ecological niche.
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Lemke, Laura B., Zhongming Ge, Mark T. Whary, Yan Feng, Arlin B. Rogers, Sureshkumar Muthupalani, and James G. Fox. "Concurrent Helicobacter bilis Infection in C57BL/6 Mice Attenuates Proinflammatory H. pylori-Induced Gastric Pathology." Infection and Immunity 77, no. 5 (February 17, 2009): 2147–58. http://dx.doi.org/10.1128/iai.01395-08.

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ABSTRACT Because coinfections can alter helicobacter gastritis, we investigated whether enterohepatic Helicobacter bilis modulates Helicobacter pylori gastritis in C57BL/6 mice. Thirty mice per group were sham dosed, H. bilis or H. pylori infected, or H. bilis infected followed in 2 weeks by H. pylori and then evaluated at 6 and 11 months postinfection (mpi) for gastritis and premalignant lesions. Compared to H. pylori-infected mice, H. bilis/H. pylori-infected mice at 6 and 11 mpi had less severe gastritis, atrophy, mucous metaplasia and hyperplasia (P < 0.01) and, additionally, at 11 mpi, less severe intestinal metaplasia and dysplasia (P < 0.05). H. bilis/H. pylori-infected mice at 11 mpi exhibited less Ki67 labeling of proliferating epithelial cells, reduced numbers of FoxP3+ T-regulatory (TREG) cells, and lower FoxP3+ mRNA levels than did H. pylori-infected mice (P < 0.05). Proinflammatory interleukin-1β (IL-1β), gamma interferon, and tumor necrosis factor alpha mRNA levels were attenuated in H. bilis/H. pylori-infected mice at 6 and 11 mpi (P < 0.01), although anti-inflammatory IL-10, IL-13, and transforming growth factor β1 mRNA levels were not consistently impacted by H. bilis coinfection. Decreased pathology in H. bilis/H. pylori-infected mice correlated with higher gastric H. pylori colonization at 6 mpi (P < 0.001) and lower Th1-associated immunoglobulin G2c responses to H. pylori at 6 and 10 mpi (P < 0.05). We hypothesized that reduced pathology in H. bilis/H. pylori-infected mice was due to H. bilis-primed TREG cells in the lower bowel that migrated to the gastric compartment and inhibited Th1 responses to subsequent H. pylori infection. Thus, H. pylori-induced gastric lesions may vary in mouse models of unknown enteric helicobacter infection status and, importantly, variable sequelae to human H. pylori infection, particularly in developing countries, may occur where coinfection with lower bowel helicobacters and H. pylori may be common.
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Han, S. R., C. Schindel, R. Genitsariotis, E. Märker-Hermann, S. Bhakdi, and M. J. Maeurer. "Identification of a Unique HelicobacterSpecies by 16S rRNA Gene Analysis in an Abdominal Abscess from a Patient with X-Linked Hypogammaglobulinemia." Journal of Clinical Microbiology 38, no. 7 (2000): 2740–42. http://dx.doi.org/10.1128/jcm.38.7.2740-2742.2000.

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A unique Helicobacter species, MZ640285, was isolated from a patient with X-linked hypogammaglobulinemia suffering from recurrent abdominal abscesses and was identified by 16S rRNA gene sequence analysis. In the phylogenetic tree, the isolate fell into a cluster which included Flexispira rappini,Helicobacter bilis, and Helicobacter sp. strain Mainz. Helicobacters are being increasingly recognized as pathogens in immunocompromised hosts. These fastidious bacteria are not easily cultured in the routine diagnostic laboratory, and this is the first report of their identification by 16S rRNA gene sequencing performed directly from a clinical specimen.
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Hänninen, M. L., R. I. Kärenlampi, J. M. K. Koort, T. Mikkonen, and K. J. Björkroth. "Extension of the species Helicobacter bilis to include the reference strains of Helicobacter sp. flexispira taxa 2, 3 and 8 and Finnish canine and feline flexispira strains." International Journal of Systematic and Evolutionary Microbiology 55, no. 2 (March 1, 2005): 891–98. http://dx.doi.org/10.1099/ijs.0.63245-0.

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The evolution and taxonomy of enterohepatic Helicobacter species with flexispira morphology were studied by a polyphasic approach including phenotypic characterization, analysis of 16S rRNA and ureB gene sequences and dot-blot DNA–DNA hybridization of whole genomic DNA. In addition, available phylogenetic data on the HSP60 gene were used in the analysis. The study included 14 Finnish canine and feline flexispira strains, the reference strains of Helicobacter sp. flexispira taxa 2, 3 and 8 and Helicobacter bilis ATCC 51630T. Phenotypically, all canine and feline strains were similar to H. bilis. Analysis of 16S rRNA gene sequences of these strains revealed a similarity of 97–99·5 %. Similarity of ureB nucleotide and amino acid sequences within the studied flexispira group was 97–100 % and 99–100 %, respectively, revealing close relatedness. ureB sequences of Helicobacter hepaticus had only 64–66 % similarity to the flexispira group. The similarity to Helicobacter trogontum was 81·5–82·1 %. High levels of DNA–DNA hybridization between the strains were found in dot-blot tests. Polyphasic analysis of the phenotypic and genotypic characteristics of the Finnish flexispira strains and the reference strains of taxa 2, 3 and 8 showed that they differed from other Helicobacter species and are members of the previously described species H. bilis. In addition, canine strain F56 differed in all phylogenetic analyses from the H. bilis group and probably represents a novel Helicobacter species.
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Jacobsen, K., E. Mahabir, M. Brielmeier, P. Wilhelm, K. E. Seidel, and J. Schmidt. "Monitoring a mouse colony for Helicobacter bilis using a Helicobacter-genus-specific nested PCR." Laboratory Animals 39, no. 4 (October 1, 2005): 400–412. http://dx.doi.org/10.1258/002367705774286402.

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Although Helicobacter infections of laboratory mice are usually subclinical, they may interfere with in vivo experiments and thus may lead to misinterpretation of data. As such, it is important to provide a means to unequivocally identify infections with murine Helicobacter spp. In the present study, a nested polymerase chain reaction (PCR) was established and shown to be 10 to 100 times more sensitive than the single-step PCR commonly used for routine diagnosis of Helicobacter spp. Experimental infection of Helicobacter-free mice demonstrated that faeces, caecum, colon and rectum but not liver are equally suitable for the detection of H. bilis. However, use of faecal pellets is advantageous since detection of H. bilis is possible one week after infection and analysis of faeces instead of tissues avoids euthanasia of animals. Furthermore, it generates representative data for all animals housed in the same cage and analysis can be repeatedly performed. Use of samples from breeding pairs but not offspring provides representative information about the Helicobacter status of a mouse colony. Both C3H/HeJ and C57BL/6 mice appear to be susceptible to H. bilis and persistent infection was observed during the 20-week experimental period. Analysis of pooled faecal pellets by nested PCR seems to be the most sensitive approach for H. bilis monitoring of the given breeding colony.
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Pisani, Paola, Mark T. Whary, Ingrid Nilsson, Supannee Sriamporn, Torkel Wadström, James G. Fox, Åsa Ljungh, and David Forman. "Cross-Reactivity between Immune Responses to Helicobacter bilis and Helicobacter pylori in a Population in Thailand at High Risk of Developing Cholangiocarcinoma." Clinical and Vaccine Immunology 15, no. 9 (July 2, 2008): 1363–68. http://dx.doi.org/10.1128/cvi.00132-08.

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ABSTRACT Helicobacter bilis DNA has been detected in human tissue and is a candidate for etiologic investigations on the causes of hepatic and biliary tract diseases, but reliable serologic tests need to be developed in order to pursue such investigations. The scope of this study was to assess the specificity of two assays for H. bilis immune response allowing for H. pylori, and their cross-reactivity in a population in Thailand at high risk for cholangiocarcinoma. Plasma samples from 92 Thai volunteers were independently tested in two laboratories (Massachusetts Institute of Technology [MIT] and Lund). MIT performed three analyses of H. pylori and H. bilis based either on (i) outer membrane protein (OMP) with no preabsorption or on antigens derived from whole-cell sonicate before (ii) or after (iii) preabsorption with H. pylori sonicate protein. Lund used cell surface proteins from H. pylori and H. bilis as antigens. Testing for H. bilis was preabsorbed with a whole-cell lysate of H. pylori. More than 80% of the samples were positive for H. pylori in both laboratories. As tested by MIT, 58.7% (95% confidence interval, 47.9 to 68.9%) were positive for H. bilis by OMP and 44.5% (34.1 to 55.3%) were positive for H. bilis sonicate protein, but only 15.2% (8.6 to 24.2%) remained positive after preabsorption with H. pylori sonicate protein. Lund found 34.5% of the samples positive for H. bilis (22.0 to 41.0%), which was statistically compatible with all three MIT results. Serologic responses to OMPs of the two bacteria coincided in 66 and 45% of the samples in the MIT and Lund assays, respectively. We found high cross-reactivity between the immune responses to H. pylori and H. bilis antigens. More-specific H. bilis antigens need to be isolated to develop serologic tests suitable for epidemiological studies.
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Rossi, Mirko, Renato Giulio Zanoni, and Marja-Liisa Hänninen. "Delineation of two Helicobacter bilis genomospecies: implications for systematics and evolution." International Journal of Systematic and Evolutionary Microbiology 60, no. 10 (October 1, 2010): 2392–97. http://dx.doi.org/10.1099/ijs.0.016287-0.

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The evolution and taxonomy of Helicobacter bilis strains isolated in Italy and Finland were studied by phylogenetic analysis of different genes, comparative analysis of small rRNA gene intervening sequence (IVS), amplified fragment length polymorphism analysis and DNA–DNA hybridization. The results of this study divided the H. bilis strains into two distinct and divergent genomic groups. In the absence of a specific phenotype or pathotype to distinguish these groups, however, they may be referred to as two genomospecies: H. bilis sensu stricto and Helicobacter sp. FL56. The phylogenetic network of gyrB and ureB gene sequences, as well as the comparative analysis of small rRNA gene IVS, suggests independent evolution of the two genomospecies. In particular, Helicobacter sp. FL56 seems to be the result of adaptation of an ancestral H. bilis strain in a new host. The phenomenon of adaptation to different hosts, or different intestinal niches in the same host, associated with high mutation and recombination rates could explain the evolution and the complex taxonomy of the genus Helicobacter. A comprehensive phylogenomics study of this genus would be useful to properly investigate this hypothesis.
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Feng, Sunlian, Lon V. Kendall, Emir Hodzic, Scott Wong, Edward Lorenzana, Kimberly Freet, Karin S. Ku, Paul A. Luciw, Stephen W. Barthold, and Imran H. Khan. "Recombinant Helicobacter bilis Protein P167 for Mouse Serodiagnosis in a Multiplex Microbead Assay." Clinical Diagnostic Laboratory Immunology 11, no. 6 (November 2004): 1094–99. http://dx.doi.org/10.1128/cdli.11.6.1094-1099.2004.

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ABSTRACT Infection of mice with Helicobacter bilis is widespread in research and commercial mouse colonies. Therefore, sensitive, specific, and high-throughput assays are needed for rapid and accurate testing of mice in large numbers. This report describes a novel multiplex assay, based on fluorescent microbeads, for serodetection of H. bilis infection. The assay requires only a few microliters of serum to perform and is amenable to a high-throughput format. Individual microbead sets were conjugated to purified, H. bilis-specific, recombinant proteins P167C and P167D and bacterial membrane extracts from H. bilis and Helicobacter hepaticus. For detecting H. bilis infection in the microbead multiplex assay, P167C and P167D provided significantly higher sensitivities (94 and 100%, respectively) and specificities (100 and 95%, respectively) than membrane extract (78% sensitivity and 65% specificity). Microbead multiplex assay results were validated by enzyme-linked immunosorbent assay. Purified recombinant proteins showed low batch-to-batch variation; this feature allows for ease of quality control, assay robustness, and affordability. Thus, recombinant antigens are highly suitable in the multiplex microbead assay format for serodetection of H. bilis infection.
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Feng, Sunlian, Emir Hodzic, Lon V. Kendall, Amy Smith, Kimberly Freet, and Stephen W. Barthold. "Cloning and Expression of a Helicobacter bilis Immunoreactive Protein." Clinical and Vaccine Immunology 9, no. 3 (May 2002): 627–32. http://dx.doi.org/10.1128/cdli.9.3.627-632.2002.

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ABSTRACT In an effort to identify immunoreactive Helicobacter bilis antigens with potential for serodiagnosis, sera from mice experimentally infected with H. bilis were used to screen an H. bilis genomic DNA expression library. Among 17 immunoreactive clones, several contained sequences that encoded a predicted 167-kDa protein (P167). Five overlapping P167 peptides (P167A to P167E) of approximately 40 kDa each were generated and tested. Immune sera reacted with fragments P167C and P167D at dilutions of 1:1,600 and 1:6,400, respectively, and reacted with an H. bilis membrane extract at a dilution of 1:800 in an enzyme-linked immunosorbent assay. Sera from mice experimentally infected with H. hepaticus did not react with P167C and P167D. Sera from mice naturally infected with H. bilis but not sera from mice naturally infected with H. hepaticus reacted with P167C and P167D. Hyperimmune sera against P167C peptide reacted with recombinant P167C and with a 120-kDa band in H. bilis lysates but did not react with a protein of the same size on immunoblots prepared from H. hepaticus, H. muridarum, or unrelated Borrelia burgdorferi and Campylobacter jejuni whole-cell lysates. Nevertheless, the P167A, P167B, P167C, and P167D primers, but not the P167E primers, amplified DNA from H. hepaticus, and all five primer sets amplified DNA from H. muridarum. These results suggest that P167 is an immunodominant, H. bilis-specific antigen that may have potential for use in serodiagnosis.
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Ge, Zhongming, Peter Doig, and James G. Fox. "Characterization of Proteins in the Outer Membrane Preparation of a Murine Pathogen, Helicobacter bilis." Infection and Immunity 69, no. 5 (May 1, 2001): 3502–6. http://dx.doi.org/10.1128/iai.69.5.3502-3506.2001.

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ABSTRACT Helicobacter bilis is a bacterial pathogen associated with multifocal hepatitis and inflammatory bowel disease in certain strains of mice. This bacterium colonizes the liver, bile, and lower intestine in mice and has also been isolated from a wide spectrum of laboratory animals. In this study, proteins present in the outer membrane preparation (OMP) of four H. bilis strains isolated from a mouse, a dog, a rat, and a gerbil were characterized and compared with that of Helicobacter pylori, a human gastric pathogen. All four H. bilis strains had similar OMP protein profiles that were distinct from those of H. pylori. Immunoblotting demonstrated that OMP proteins fromH. bilis and H. pylori have little cross-reactivity, except for their flagellins. Nine major immunogenic polypeptides were present in the H. bilis OMPs. By using two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis, five heat-modifiable proteins with molecular masses of 82, 66, 52, 47 and 37 kDa were identified. The N-terminal sequences of the 46- and 47-kDa OMP proteins had no homology with protein sequences available in public databases. These results indicate that H. bilis has a conserved, unique OMP protein profile that is distinct from those of H. pylori.
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Dissertations / Theses on the topic "Helicobacter bilis"

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Okoli, Arinze Stanley Medical Sciences Faculty of Medicine UNSW. "Molecular studies of the response of Helicobacter hepaticus to bile, and the effect of Helicobacter bilis on human hepatoma cells." Publisher:University of New South Wales. Medical Sciences, 2009. http://handle.unsw.edu.au/1959.4/43379.

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Enterohepatic Helicobacter species (EHS) are emerging infectious disease agents. Infection of the enterohepatobiliary tract of several mammals by this group of bacteria results in various pathological disorders. The availability of the Helicobacter hepaticus sequenced and annotated genome, allowed molecular characterisation of the responses of H. hepaticus to host factors such as bile. The adaptation/responses of the bacterium to bovine, porcine and human bile were investigated using proteomics and transcriptomics. Ninety-one different proteins were identified in the responses of H. hepaticus response to the three types of bile. These proteins participate in several key cellular processes including DNA replication; protein transcription, translation and folding; oxidative stress response; motility; virulence; and metabolism. In particular, the bacteria deployed several strategies such as inhibition of the TCA cycle and the electron transport chain as well as iron sequestration to ensure control of the levels of hydroxyl radicals. The results of this study revealed also the modulation by bile of the expression of H. hepaticus genes involved in response to oxidative stress and virulence. The responses of human HEp-2 and Huh7-derived cell-lines to H. hepaticus and Helicobacter bilis, respectively, were investigated employing proteomics and transcriptomics. One-hundred and twenty different proteins were differentially expressed in the responses of the human cells to the presence of Helicobacter spp. in the cell cultures. These proteins are involved in regulation of cell proliferation and structure; metabolism; protein transcription, translation and modification; stress response; and tumour induction. For example, in co-cultures of Huh7-derived cells and H. bilis, the activation of several mitochondrial and endoplasmic reticulum stress-related proteins and the dysregulation of several apoptosis effectors were suggested as mechanisms that could result in the death of the liver cells. Importantly, the differential expression of several tumour-related proteins by the Huh7 cells supported a possible role for Helicobacter spp. in liver cancer.
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Book chapters on the topic "Helicobacter bilis"

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Fox, J. G. "Helicobacter hepaticus and Helicobacter bilis: proinflammatory modulators of enterohepatic disease." In Helicobactor pylori, 15–29. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-1763-2_2.

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