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Prevalence of Coinfection with Gastric Non‐Helicobacter pylori Helicobacter (NHPH) Species in Helicobacter pylori‐infected Patients Suffering from Gastric Disease in Beijing,China
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Jie Liu Lihua He Freddy Haesebrouck Yanan Gong Bram Flahou Qizhi Cao Jianzhong Zhang 《Helicobacter》2015,20(4):284-290
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Monotherapy with a novel intervenolin derivative,AS‐1934, is an effective treatment for Helicobacter pylori infection
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Tomokazu Ohishi Tohru Masuda Hikaru Abe Chigusa Hayashi Hayamitsu Adachi Shun‐ichi Ohba Masayuki Igarashi Takumi Watanabe Hitomi Mimuro Eri Amalia Daniel Ken Inaoka Kota Mochizuki Kiyoshi Kita Masakatsu Shibasaki Manabu Kawada 《Helicobacter》2018,23(2)
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Hassan Ashktorab Rod H. Dashwood Mohaiza M. Dashwood Syed I. Zaidi Stephen M. Hewitt William R. Green Edward L. Lee Mohammadreza Daremipouran Mehdi Nouraie Reza Malekzadeh Duane T. Smoot 《Helicobacter》2008,13(6):506-517
Background and Aim: Our previous study of Helicobacter pylori‐induced apoptosis showed the involvement of Bcl‐2 family proteins and cytochrome c release from mitochondria. Here, we examine the release of other factors from mitochondria, such as apoptosis‐inducing factor (AIF), and upstream events involving caspase‐8 and Bid. Methods: Human gastric adenocarcinoma (AGS) cells were incubated with a cagA‐positive H. pylori strain for 0, 3, 6, and 24 hours and either total protein or cytoplasmic, nuclear, and mitochondrial membrane fractions were collected. Results: Proteins were immunoblotted for AIF, Bid, polyadenosine ribose polymerase (PARP), caspase‐8, and β‐catenin. H. pylori activated caspase‐8, caused PARP cleavage, and attenuated mitochondrial membrane potential. A time‐dependent decrease in β‐catenin protein expression was detected in cytoplasmic and nuclear extracts, coupled with a decrease in β‐actin. An increase in the cytoplasmic pool of AIF was seen as early as 3 hours after H. pylori exposure, and a concomitant increase was seen in nuclear AIF levels up to 6 hours. A band corresponding to full‐length Bid was seen in both the cytoplasmic and the nuclear fractions of controls, but not after H. pylori exposure. Active AIF staining was markedly increased in gastric mucosa from infected persons, compared to uninfected controls. Conclusion: H. pylori might trigger apoptosis in AGS cells via interaction with death receptors in the plasma membrane, leading to the cleavage of procaspase‐8, release of cytochrome c and AIF from mitochondria, and activation of subsequent downstream apoptotic events, as reported previously for chlorophyllin. This is consistent with AIF activation that was found in the gastric mucosa of humans infected with H. pylori. Hence, the balance between apoptosis and proliferation in these cells may be altered in response to injury caused by H. pylori infection, leading to an increased risk of cancer. 相似文献
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Enhanced Expression of Indoleamine 2,3‐Dioxygenase in Helicobacter pylori‐Infected Human Gastric Mucosa Modulates Th1/Th2 Pathway and Interleukin 17 Production
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Tiziana Larussa Isabella Leone Evelina Suraci Immacolata Nazionale Teresa Procopio Francesco Conforti Ludovico Abenavoli Marta L. Hribal Maria Imeneo Francesco Luzza 《Helicobacter》2015,20(1):41-48
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Nagaja Capitani Gaia Codolo Francesca Vallese Giovanni Minervini Alessia Grassi Fabio Cianchi Arianna Troilo Wolfgang Fischer Giuseppe Zanotti Cosima T. Baldari Marina de Bernard Mario M. D'Elios 《Cellular microbiology》2019,21(5)
Helicobacter pylori (HP) is a Gram‐negative bacterium that chronically infects the stomach of more than 50% of human population and represents a major cause of gastric cancer, gastric lymphoma, gastric autoimmunity, and peptic ulcer. It still remains to be elucidated, which HP virulence factors are important in the development of gastric disorders. Here, we analysed the role of the HP protein HP1454 in the host–pathogen interaction. We found that a significant proportion of T cells isolated from HP patients with chronic gastritis and gastric adenocarcinoma proliferated in response to HP1454. Moreover, we demonstrated in vivo that HP1454 protein drives Th1/Th17 inflammatory responses. We further analysed the in vitro response of human T cells exposed either to an HP wild‐type strain or to a strain with a deletion of the hp1454 gene, and we revealed that HP1454 triggers the T‐cell antigen receptor‐dependent signalling and lymphocyte proliferation, as well as the CXCL12‐dependent cell adhesion and migration. Our study findings prove that HP1454 is a crucial bacterial factor that exerts its proinflammatory activity by directly modulating the T‐cell response. The relevance of these results can be appreciated by considering that compelling evidence suggest that chronic gastric inflammation, a condition that paves the way to HP‐associated diseases, is dependent on T cells. 相似文献
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Gert Carra Nicole Tegtmeyer Tim Geppert Peter Schröder Norbert Sewald Steffen Backert Silja Wessler 《EMBO reports》2010,11(10):798-804
Mammalian and prokaryotic high‐temperature requirement A (HtrA) proteins are chaperones and serine proteases with important roles in protein quality control. Here, we describe an entirely new function of HtrA and identify it as a new secreted virulence factor from Helicobacter pylori, which cleaves the ectodomain of the cell‐adhesion protein E‐cadherin. E‐cadherin shedding disrupts epithelial barrier functions allowing H. pylori designed to access the intercellular space. We then designed a small‐molecule inhibitor that efficiently blocks HtrA activity, E‐cadherin cleavage and intercellular entry of H. pylori. 相似文献
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J. Wu B.A. Boghigian M. Myint H. Zhang S. Zhang B.A. Pfeifer 《Letters in applied microbiology》2010,51(2):196-204
Aims: Escherichia coli has emerged as a viable heterologous host for the production of complex, polyketide natural compounds. In this study, polyketide biosynthesis was compared between different E. coli strains for the purpose of better understanding and improving heterologous production. Methods and Results: Both B and K‐12 E. coli strains were genetically modified to support heterologous polyketide biosynthesis [specifically, 6‐deoxyerythronolide B (6dEB)]. Polyketide production was analysed using a helper plasmid designed to overcome rare codon usage within E. coli. Each strain was analysed for recombinant protein production, precursor consumption, by‐product production, and 6dEB biosynthesis. Of the strains tested for biosynthesis, 6dEB production was greatest for E. coli B strains. When comparing biosynthetic improvements as a function of mRNA stability vs codon bias, increased 6dEB titres were observed when additional rare codon tRNA molecules were provided. Conclusions: Escherichia coli B strains and the use of tRNA supplementation led to improved 6dEB polyketide titres. Significance and Impact of the Study: Given the medicinal potential and growing field of polyketide heterologous biosynthesis, the current study provides insight into host‐specific genetic backgrounds and gene expression parameters aiding polyketide production through E. coli. 相似文献
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Daniela Bustos‐Korts Ian K. Dawson Joanne Russell Alessandro Tondelli Davide Guerra Chiara Ferrandi Francesco Strozzi Ezequiel L. Nicolazzi Marta Molnar‐Lang Hakan Ozkan Maria Megyeri Peter Miko Esra akr Enes Yakr Noemi Trabanco Stefano Delbono Stylianos Kyriakidis Allan Booth Davide Cammarano Martin Mascher Peter Werner Luigi Cattivelli Laura Rossini Nils Stein Benjamin Kilian Robbie Waugh Fred A. van Eeuwijk 《The Plant journal : for cell and molecular biology》2019,99(6):1172-1191
Broadening the genetic base of crops is crucial for developing varieties to respond to global agricultural challenges such as climate change. Here, we analysed a diverse panel of 371 domesticated lines of the model crop barley to explore the genetics of crop adaptation. We first collected exome sequence data and phenotypes of key life history traits from contrasting multi‐environment common garden trials. Then we applied refined statistical methods, including some based on exomic haplotype states, for genotype‐by‐environment (G×E) modelling. Sub‐populations defined from exomic profiles were coincident with barley's biology, geography and history, and explained a high proportion of trial phenotypic variance. Clear G×E interactions indicated adaptation profiles that varied for landraces and cultivars. Exploration of circadian clock‐related genes, associated with the environmentally adaptive days to heading trait (crucial for the crop's spread from the Fertile Crescent), illustrated complexities in G×E effect directions, and the importance of latitudinally based genic context in the expression of large‐effect alleles. Our analysis supports a gene‐level scientific understanding of crop adaption and leads to practical opportunities for crop improvement, allowing the prioritisation of genomic regions and particular sets of lines for breeding efforts seeking to cope with climate change and other stresses. 相似文献
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Cholesterol‐α‐glucosyltransferase gene is present in most Helicobacter species including gastric non‐Helicobacter pylori helicobacters obtained from Japanese patients
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Masatomo Kawakubo Kazuki Horiuchi Takehisa Matsumoto Jun Nakayama Taiji Akamatsu Tsutomu Katsuyama Hiroyoshi Ota Junji Sagara 《Helicobacter》2018,23(1)
Background
Non‐Helicobacter pylori helicobacters (NHPHs) besides H. pylori infect human stomachs and cause chronic gastritis and mucosa‐associated lymphoid tissue lymphoma. Cholesteryl‐α‐glucosides have been identified as unique glycolipids present in H. pylori and some Helicobacter species. Cholesterol‐α‐glucosyltransferase (αCgT), a key enzyme for the biosynthesis of cholesteryl‐α‐glucosides, plays crucial roles in the pathogenicity of H. pylori. Therefore, it is important to examine αCgTs of NHPHs.Materials and Methods
Six gastric NHPHs were isolated from Japanese patients and maintained in mouse stomachs. The αCgT genes were amplified by PCR and inverse PCR. We retrieved the αCgT genes of other Helicobacter species by BLAST searches in GenBank.Results
αCgT genes were present in most Helicobacter species and in all Japanese isolates examined. However, we could find no candidate gene for αCgT in the whole genome of Helicobacter cinaedi and several enterohepatic species. Phylogenic analysis demonstrated that the αCgT genes of all Japanese isolates show high similarities to that of a zoonotic group of gastric NHPHs including Helicobacter suis, Helicobacter heilmannii, and Helicobacter ailurogastricus. Of 6 Japanese isolates, the αCgT genes of 4 isolates were identical to that of H. suis, and that of another 2 isolates were similar to that of H. heilmannii and H. ailurogastricus.Conclusions
All gastric NHPHs examined showed presence of αCgT genes, indicating that αCgT may be beneficial for these helicobacters to infect human and possibly animal stomachs. Our study indicated that NHPHs could be classified into 2 groups, NHPHs with αCgT genes and NHPHs without αCgT genes. 相似文献20.
Development of a sequence‐characterized amplified region marker using inter‐simple sequence repeats for detection of Puccinia striiformis f. sp. tritici
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Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is the most devastating wheat disease in China. Early and accurate detection of the pathogens would facilitate effective control of the diseases. DNA‐based methods now provide essential tools for accurate plant disease diagnosis. In this study, inter‐simple sequence repeats (ISSR) technique has been successfully applied to develop a sequence‐characterized amplified region (SCAR) marker for diagnosis of stripe rust of wheat and detection of Pst. In this study, one fragment unique to Pst was identified by ISSR and then sequenced. Based on the specific fragment, a pair of SCAR primers (616AF/616AR) was designed to amplify a 299‐bp DNA fragment within the sequenced region. The primers can amplify a unique DNA fragment for all tested isolates of Pst but not for the other pathogens of wheat leaves and the uninfected leaves. The polymerase chain reaction (PCR) assay could detect as low as 0.1 ng of genomic DNA in a 25.0 μl PCR reaction mixture and detect the pathogen from asymptomatic wheat leaves inoculated with Pst under glasshouse conditions. 相似文献