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down-regulation of bcl-2 is mediated by nf-κb activation in helicobacter pylori-induced apoptosis of gastric epithelial cells.bcl-2 family is involved in the regulation of apoptosis. nf-κb activation is associated with either the expression of bcl-2 or down-regulation of bcl-2 depending on cell types and stimuli. previously, we showed nf-κb activation, decrease in the level of bcl-2, and apoptosis in helicobacter pylori (h. pylori)-infected gastric epithelial cells. the present study aims to investigate the relation of bcl-2 expression and nf-κb activation in h. pylori-induced apoptotic cell death of ags (gastric adeno ...201020969490
cdx2 autoregulation in human intestinal metaplasia of the stomach: impact on the stability of the phenotype.intestinal metaplasia (im) is a gastric preneoplastic lesion that appears following helicobacter pylori infection and confers an increased risk for development of cancer. it is induced by gastric expression of the intestine-specific transcription factor cdx2. the regulatory mechanisms involved in triggering and maintaining gastric cdx2 expression have not been fully elucidated. the cdx2(+/-) mouse develops intestinal polyps with gastric differentiation and total loss of cdx2 expression in the ab ...201021148572
structural determinants of inhibitor selectivity in prokaryotic imp dehydrogenases.the protozoan parasite cryptosporidium parvum is a major cause of gastrointestinal disease; no effective drug therapy exists to treat this infection. curiously, c. parvum impdh (cpimpdh) is most closely related to prokaryotic impdhs, suggesting that the parasite obtained its impdh gene via horizontal transfer. we previously identified inhibitors of cpimpdh that do not inhibit human impdhs. here, we show that these compounds also inhibit impdhs from helicobacter pylori, borrelia burgdorferi, and ...201021035731
mthfr c677t polymorphism and differential methylation status in gastric cancer: an association with helicobacter pylori infection.mthfr c677t and helicobacter pylori infection are believed to play critical roles in the dna methylation process, an epigenetic feature frequently found in gastric cancer. the aim of this study was to verify the associations between the mthfr c677t polymorphism and the methylation status of three gastric cancer-related genes. the influence of h. pylori strains was also assessed. dna extracted from 71 gastric tumor samples was available for mthfr c677t genotyping by pcr-rflp, promoter methylation ...201020957490
local recall responses in the stomach involving reduced regulation and expanded help mediate vaccine-induced protection against helicobacter pylori in mice.helicobacter pylori is recognised as the chief cause of chronic gastritis, ulcers and gastric cancer in humans. with increased incidence of treatment failure and antibiotic resistance, development of prophylactic or therapeutic vaccination is a desirable alternative. although the results of vaccination studies in animal models have been promising, studies in human volunteers have revealed problems such as 'post-immunisation gastritis' and comparatively poor responses to vaccine antigens. the foc ...201021038469
consequences of helicobacter pylori infection in children.although evidence is emerging that the prevalence of helicobacter pylori (h. pylori) is declining in all age groups, the understanding of its disease spectrum continues to evolve. if untreated, h. pylori infection is lifelong. although h. pylori typically colonizes the human stomach for many decades without adverse consequences, children infected with h. pylori can manifest gastrointestinal diseases. controversy persists regarding testing (and treating) for h. pylori infection in children with r ...201021049552
the effect of cytochrome p2c19 and interleukin-1 polymorphisms on h. pylori eradication rate of 1-week triple therapy with omeprazole or rabeprazole, amoxycillin and clarithromycin in chinese people.what is known and objective: genetic polymorphism of interleukin (il)-1β and il-1 receptor antagonist (il-1rα) are associated with efficacy of acid suppression, whereas cytochrome p (cyp) 2c19 polymorphism influences the metabolism of proton pump inhibitor family. thus, cyp2c19 and il-1 polymorphisms may affect the efficacy of h. pylori eradication therapy. we compared the efficacies of omeprazole and rabeprazole on eradication of h. pylori in relation to cyp2c19, il-1b and il-1rn genotypes in c ...201021054464
helicobacter spp. other than helicobacter pylori.over the last 12 months, new insights into the association of non-helicobacter pylori helicobacters with a range of human diseases in children and adults, including hepatobiliary disease, crohn's disease, sepsis, and gastric disease were published. studies investigating the presence of non-h. pylori helicobacters in domestic animals reinforce previous findings that cats and dogs harbor gastric helicobacter species and thus may be an important source of these organisms in humans. the confounding ...201021054656
role of helicobacter pylori infection in aberrant dna methylation along multistep gastric carcinogenesis.cpg island hypermethylation is frequently found during gastric carcinogenesis. we investigated methylation profiles of p16, lox, hand1, thbd, p41arc, and apc along multistep gastric carcinogenesis and determined their association with helicobacter pylori infection. methylation levels in these six genes were evaluated in noncancerous gastric biopsy specimens using quantitative methylation-specific pcr in 459 patients with gastric cancer (gc), 137 with dysplasia, and 248 controls. controls were di ...201020345486
induction of paranodal myelin detachment and sodium channel loss in vivo by campylobacter jejuni dna-binding protein from starved cells (c-dps) in myelinated nerve fibers.in an axonal variant of guillain-barré syndrome (gbs) associated with campylobacter jejuni (c. jejuni) enteritis, the mechanism underlying axonal damage is obscure. we purified and characterized a dna-binding protein from starved cells derived from c. jejuni (c-dps). this c-dps protein has significant homology with helicobacter pylori neutrophil-activating protein (hp-nap), which is chemotactic for human neutrophils through binding to sulfatide. because sulfatide is essential for paranodal junct ...201019880143
helicobacter pylori caga phosphorylation status determines the gp130-activated shp2/erk and jak/stat signal transduction pathways in gastric epithelial cells.the helicobacter pylori protein caga may undergo tyrosine phosphorylation following its entry into human gastric epithelial cells with downstream effects on signal transduction. disruption of the gp130 receptor that modulates the balance of the shp2/erk and jak/stat pathways enhanced peptic ulceration and gastric cancer in gp130 knock-out mice. in this study, we evaluated the effect of translocated caga in relation to its tyrosine phosphorylation status on the gp130-mediated signal switch betwee ...201020348091
[polymorphism of cytokine genes in the development of helicobacter pylori infection].the purpose of this work was to study morphological features of gastric mucosa depending on polymorphism of il-l1beta and il-1rn genes in children with chronic gastritis infected with different strains of helicobacter pylori 0. we examined 106 children with hp-associated gastritis. the results suggest association of mucosal inflammation with t allele in polymorphous c-511t locus of il-1beta (beta2 = 14,006; alpha = 0.001). aga + strains of hp were more frequently identified in patients with eros ...201020364673
angiogenesis and lymphangiogenesis of gastric cancer.tumor angiogenesis is the result of an imbalance between positive and negative angiogenic factors released by tumor and host cells into the microenvironment of the neoplastic tissue. the stroma constitutes a large part of most solid tumors, and cancer-stromal cell interactions contribute functionally to tumor growth and metastasis. activated fibroblasts and macrophages in tumor stroma play important roles in angiogenesis and tumor progression. in gastric cancer, tumor cells and stromal cells pro ...201020369064
helicobacter pylori dupa is polymorphic, and its active form induces proinflammatory cytokine secretion by mononuclear cells.infection with helicobacter pylori possessing a newly described virulence factor--duodenal ulcer-promoting gene a (dupa)--has been associated with duodenal ulceration and increased gastric inflammation.201020533870
the role of small molecular weight compounds to increase vacuolation induced by vaca toxin in vitro.vaca is a vacuolation protein toxin secreted by helicobacter pylori. many compounds have been implicated in the regulation of vaca toxin activity. in this study, regulation of cell vacuolation induced by vaca was observed with the addition of glycine, glycine hydrochloride, xylitol, and taurine by neutral red dye uptake assay using gastric human epithelial cell cultures. glycine, xylitol, and taurine increased cell vacuolation significantly after 48h (p<0.05), with their effect apparent in a wid ...201020403422
b-cell receptor signaling and cd40 ligand-independent t cell help cooperate in helicobacter-induced malt lymphomagenesis.gastric b-cell lymphoma of mucosa-associated lymphoid tissue (malt) develops in the context of chronic inflammation caused by helicobacter pylori infection. most pathophysiological features of the early stages of malt lymphomagenesis can be reproduced by experimental infection of balb/c mice with helicobacter species. we have previously shown that malt lymphomas are infiltrated by t-helper cell type 2-polarized t cells and that human and murine tumor b cells carry polyreactive surface immunoglob ...201020428202
up-regulated microrna-146a negatively modulate helicobacter pylori-induced inflammatory response in human gastric epithelial cells.helicobacter pylori (h. pylori) is a major human pathogenic bacterium in gastric mucosa. however, the regulatory mechanism of h. pylori-induced immune response is not clear. micrornas (mirnas) have recently emerged as key post-transcriptional regulators of gene expression, and their role in h. pylori infection is just beginning to be explored. here, we first reported that h. pylori infection up-regulated the expression of mir-146a in gastric epithelial cells as well as in gastric mucosal tissues ...201020542134
muc1 cell surface mucin attenuates epithelial inflammation in response to a common mucosal pathogen.helicobacter pylori infection of the gastric mucosa causes an active-chronic inflammation that is strongly linked to the development of duodenal and gastric ulcers and stomach cancer. however, greater than 80% of individuals infected with h. pylori are asymptomatic beyond histologic inflammation, and it is unknown what factors influence the incidence and character of bacterial-associated gastritis and related disorders. because previous studies demonstrated that the muc1 epithelial glycoprotein ...201020430889
refractory gastric ulcer with abundant igg4-positive plasma cell infiltration: a case report.we describe a 77-year-old man with refractory gastric ulcer that worsened after helicobacter pylori eradication therapy. pathology showed marked infiltration of igg4-positive plasma cells in the gastric lesions, which led us to suspect igg4-related sclerosing disease. to the best of our knowledge, this is the first report of igg4-related gastric ulcer without the main manifestation of autoimmune pancreatitis.201020440861
[acute upper gastrointestinal bleeding after coronary intervention in acute myocardial infarction].a 73-year-old man with nstemi (non-st segment elevation myocardial infarction) underwent coronary angiography and an in-stent restenosis and thrombosis in ramus circumflexus was found. a drug-eluting stent (des) was implanted. 12 h after intervention during threefold platelet inhibition the patient presented a gastrointestinal bleeding with melena and the hemoglobin level dropped from 15.3 g/dl to 9.7 g/dl.201020455053
chronic aspirin use suppresses cdh1 methylation in human gastric mucosa.there have been reports showing a protective role of aspirin and other nonsteroidal anti-inflammatory drugs (nsaids) against gastrointestinal cancers. e-cadherin (cdh1) is an adhesion molecule involved in tumour invasion/metastasis. silencing of cdh1 by promoter cpg island methylation was shown in gastric cancer, precancerous lesion, and helicobacter pylori-infected chronic gastritis. we investigated the methylation status of cdh1 in noncancerous gastric mucosa in chronic aspirin user, and asses ...201019184424
a comparison of the acid-inhibitory effects of esomeprazole and pantoprazole in relation to pharmacokinetics and cyp2c19 polymorphism.esomeprazole and pantoprazole are metabolized in the liver and the polymorphic cyp2c19 enzyme is involved in that process. this genetic polymorphism determines fast (70% of caucasians), intermediate (25-30% of caucasians) and slow (2-5% of caucasians) metabolism of ppis.201019785625
involvement of ras and ap-1 in helicobacter pylori-induced expression of cox-2 and inos in gastric epithelial ags cells.helicobacter pylori (h. pylori) is an important risk factor for chronic gastritis, peptic ulcer, and gastric cancer. the genetic differences of h. pylori isolates play a role in the clinical outcome of the infection. inflammatory genes including cyclooxygenase-2 (cox-2) and inducible nitric oxide synthase (inos) are involved in h. pylori gastritis. transcription factor ap-1 is composed of c-fos and c-jun and mediates inflammation and carcinogenesis. ras acts as a regulator for ap-1 activation in ...201019495976
identification of cell-surface mannans in a virulent helicobacter pylori strain.with the intent of contributing to a carbohydrate-based vaccine against the gastroduodenal pathogen, helicobacter pylori, we report here the structure of cell-surface mannans obtained from a virulent strain. unlike other wild-type strains, this strain was found to express in good quantities this polysaccharide in vitro. structural analysis revealed a branched mannan formed by a backbone of alpha-(1-->6)-linked mannopyranosyl residues with approximately 80% branching at the o-2 position. the bran ...201020227685
genetic polymorphisms in dna repair genes xpc, xpd, and xrcc4, and susceptibility to helicobacter pylori infection-related gastric antrum adenocarcinoma in guangxi population, china.genetic polymorphisms in dna repair genes may influence individual variation in dna repair capacity, which may be associated with risk of gastric antrum adenocarcinoma (gaa) related to helicobacter pylori infection. this study, including 361 gaas and 616 controls without any evidence of tumors, was designed to evaluate the association between the polymorphisms of dna repair genes xpc ala499val (rs#2228000) and lys939gln (rs#2228001), xpd lys751gln (rs#13181), and xrcc4 ala247ser (rs#3734091) and ...201020232359
high-throughput and single-cell imaging of nf-kappab oscillations using monoclonal cell lines.the nuclear factor-kappab (nf-kappab) family of transcription factors plays a role in a wide range of cellular processes including the immune response and cellular growth. in addition, deregulation of the nf-kappab system has been associated with a number of disease states, including cancer. therefore, insight into the regulation of nf-kappab activation has crucial medical relevance, holding promise for novel drug target discovery. transcription of nf-kappab-induced genes is regulated by differe ...201020233427
helicobacter pylori: bacterial factors and the role of cytokines in the immune response.helicobacter pylori is a gram-negative micro-aerophilic bacterium that is widely distributed geographically and causes chronic gastritis, peptic ulcers, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. bacterial virulence factors play an important role, since the virulent strains are more aggressive and increase the risk of developing severe clinical manifestations; in addition, other determinant factors are the nutritional state and the immune response of the host. studie ...201019847485
human primary gastric dendritic cells induce a th1 response to h. pylori.adaptive cd4 t-cell responses are important in the pathogenesis of chronic helicobacter pylori gastritis. however, the gastric antigen-presenting cells that induce these responses have not yet been identified. here we show that dendritic cells (dcs) are present in the gastric mucosa of healthy subjects and are more prevalent and more activated in the gastric mucosa of h. pylori-infected subjects. h. pylori induced gastric dcs isolated from noninfected subjects to express increased levels of cd11 ...201020237463
dual regulation by apurinic/apyrimidinic endonuclease-1 inhibits gastric epithelial cell apoptosis during helicobacter pylori infection.human apurinic/apyrimidinic endonuclease-1 (ape-1), a key enzyme involved in repair of oxidative dna base damage, is an important transcriptional coregulator. we previously reported that helicobacter pylori infection induces apoptosis and increases ape-1 expression in human gastric epithelial cells (gec). although both the dna repair activity and the acetylation-mediated transcriptional regulation of ape-1 are required to prevent cell death, the mechanisms of ape-1-mediated inhibition of infecti ...201020332233
ethnic and geographic differentiation of helicobacter pylori within iran.the bacterium helicobacter pylori colonizes the human stomach, with individual infections persisting for decades. the spread of the bacterium has been shown to reflect both ancient and recent human migrations. we have sequenced housekeeping genes from h. pylori isolated from 147 iranians with well-characterized geographical and ethnic origins sampled throughout iran and compared them with sequences from strains from other locations. h. pylori from iran are similar to others isolated from western ...201020339588
analysis of a beta-helical region in the p55 domain of helicobacter pylori vacuolating toxin.helicobacter pylori is a gram-negative bacterium that colonizes the human stomach and contributes to the development of gastric cancer and peptic ulcer disease. vaca, a toxin secreted by h. pylori, is comprised of two domains, designated p33 and p55. analysis of the crystal structure of the p55 domain indicated that its structure is predominantly a right-handed parallel beta-helix, which is a characteristic of autotransporter passenger domains. substitution mutations of specific amino acids with ...201020178613
cyp2c19 genotypes in the pharmacokinetics/pharmacodynamics of proton pump inhibitor-based therapy of helicobacter pylori infection.proton pump inhibitors (ppis) are potent gastric acid inhibitors. therapies with a ppi and antibiotics are used to cure helicobacter pylori (h. pylori) infection, which is closely related to many gastrointestinal diseases. most ppis are mainly metabolized by cytochrome 2c19 (cyp2c19). the genetic polymorphisms of cyp2c19 may lead to the differences in pharmacokinetics (pk), pharmacodynamics (pd) and clinical efficacy of ppis.201019968574
helicobacter pylori lipopolysaccharides upregulate toll-like receptor 4 expression and proliferation of gastric epithelial cells via the mek1/2-erk1/2 mitogen-activated protein kinase pathway.helicobacter pylori is recognized as an etiological agent of gastroduodenal diseases. h. pylori produces various toxic substances, including lipopolysaccharide (lps). however, h. pylori lps exhibits extremely weakly endotoxic activity compared to the typical lps, such as that produced by escherichia coli, which acts through toll-like receptor 4 (tlr4) to induce inflammatory molecules. the gastric epithelial cell lines mkn28 and mkn45 express tlr4 at very low levels, so they show very weak interl ...201019858308
methods to monitor autophagy in h. pylori vacuolating cytotoxin a (vaca)-treated cells.helicobacter pylori is a gram negative pathogen that infects at least half of the world's population and is associated not only with gastric cancer but also with other diseases such as gastritis and peptic ulcers. indeed, h. pylori is considered the single most important risk factor for the development of gastric cancer. the vacuolating cytotoxin vaca, secreted by h. pylori, promotes intracellular survival of the bacterium and modulates host immune responses. in a recent study, we reported that ...201019875940
helicobacter pylori stimulates dendritic cells to induce interleukin-17 expression from cd4+ t lymphocytes.helicobacter pylori is a human gastroduodenal pathogen that leads to active chronic inflammation characterized by t-cell responses biased toward a th1 phenotype. it has been accepted that h. pylori infection induces a th17 response. at mucosal sites, dendritic cells (dcs) have the capacity to induce effector t cells. here, we evaluate the role of dcs in the h. pylori-induced interleukin-17 (il-17) response. immunohistochemistry and immunofluorescence were performed on human gastric mucosal biops ...201019917709
elevated serum matrix metalloproteinase-3 and -7 in h. pylori-related gastric cancer can be biomarkers correlating with a poor survival.helicobacter pylori (h. pylori) infection up-regulates the expression of matrix metalloproteinases (mmps), which may be involved in chronic inflammation, ulceration, and even cancer development. this study aimed to test if serum levels of mmp-3, -7, and -9 are correlated with different clinical outcomes in h. pylori-infected subjects and if these are predictive of progression to h. pylori-related gastric cancer.201019690958
drinking air and maneuvering it to the pyloric region of the stomach for the treatment for helicobacter pylori infection.helicobacter pylori is a flagellate, gram-negative bacterium which lives in the pyloric region of the human stomach and is a major cause of a large proportion of peptic ulcers, some non-ulcer dyspepsias and rarely, gastric cancers. it is a microaerophilic (anaerobic) organism. in place of the several drugs currently in use for treating h. pylori infection, plain simple atmospheric air swallowed or sucked into the stomach, or drunk by any of the various techniques described here and then postural ...201020189723
late reactivation of sonic hedgehog by helicobacter pylori results in population of gastric epithelial cells that are resistant to apoptosis: implication for gastric carcinogenesis.as much as that a disturbance of tissue homeostasis through dysregulated apoptosis is generally associated with carcinogenesis, gastric carcinogenesis after helicobacter pylori infection could be the accumulated consequence of imbalances between apoptosis and proliferation. since sonic hedgehog (shh) has been reported to play versatile roles in various tumorigenesis, we hypothesized that late reactivation of sonic hedgehog by h. pylori infection results in population of gastric epithelial cells ...201019540662
helicobacter pylori urease activates blood platelets through a lipoxygenase-mediated pathway.the bacterium helicobacter pylori causes peptic ulcers and gastric cancer in human beings by mechanisms yet not fully understood. h. pylori produces urease which neutralizes the acidic medium permitting its survival in the stomach. we have previously shown that ureases from jackbean, soybean or bacillus pasteurii induce blood platelet aggregation independently of their enzyme activity by a pathway requiring platelet secretion, activation of calcium channels and lipoxygenase-derived eicosanoids. ...201019754669
study on the association of cox-2 genetic polymorphisms with risk of gastric cancer in high incidence hexi area of gansu province in china.to investigate the possible association of polymorphisms, cyclooxygenase-2 (cox-2) promoter region -899g>c, cox-2 codon 587g>a, with risk of gastric cancer in the high incidence hexi area of gansu province in china. blood samples from 140 patients with gastric carcinoma and 125 normal persons were collected in hexi area of gansu province in china. polymorphisms of cox-2 -899g>a and cox-2 587g>a were genotyped by pcr-taqman. for detection helicobacter pylori infection, warhin-starry staining was ...201120364406
the expression of renin-angiotensin system components in the human gastric mucosa.the aim of the present study was to map the distribution of representative protein components of the renin-angiotensin system (ras) in the human gastric mucosa.201120739374
combined effect of mir-146a rs2910164 g/c polymorphism and toll-like receptor 4 +3725 g/c polymorphism on the risk of severe gastric atrophy in japanese.a g/c polymorphism in mirna-146a (rs2910164) was shown to be associated with the risk of hepatocellular carcinoma.201120721625
transferring network topological knowledge for predicting protein-protein interactions.protein-protein interactions play an important role in cellular processes within a cell. an important task is to determine the existence of interactions among proteins. unfortunately, existing biological experimental techniques are expensive, time-consuming and labor-intensive. the network structures of many such networks are sparse, incomplete and noisy. thus, state-of-the-art methods for link prediction in these networks often cannot give satisfactory prediction results, especially when some n ...201121770035
bacterial virulence in the moonlight: multitasking bacterial moonlighting proteins are virulence determinants in infectious disease.men may not be able to multi-task, but it is emerging that proteins can. this capacity of proteins to exhibit more than one function is termed protein moonlighting and, surprisingly, many highly conserved proteins involved in metabolic regulation or the cell stress response have a range of additional biological actions which are involved in bacterial virulence. this review highlights the multiple roles exhibited by a range of bacterial proteins, such as glycolytic and other metabolic enzymes and ...201121646455
architecture of the helicobacter pylori cag-type iv secretion system.type iv secretion systems (t4ss) are macromolecular assemblies used by bacteria to transport material across their membranes. t4ss are generally composed of a set of twelve proteins (virb1-11 and vird4). this represents a dynamic machine powered by three atpases. t4ss are widespread in pathogenic bacteria where they are often used to deliver effectors into host cells. for example, the human pathogen helicobacter pylori encodes a t4ss, the cag-t4ss, which mediates the injection of the toxin caga. ...201121352491
antigenic diversity among portuguese clinical isolates of helicobacter pylori.ôçéthe human gastroduodenal pathogen, helicobacter pylori, is characterized by an unusual extent of genetic heterogeneity. this dictates differences in the antigenic pattern of strains resulting in heterogeneous human humoral immune responses. here, we examined the antigenic variability among a group of 10 strains isolated from portuguese patients differing in age, gender, and h. pylori-associated gastric diseases.201121435094
determination of strains of helicobacter pylori and of polymorphism in the interleukin-8 gene in patients with stomach cancer.gastric neoplasia is the second most common cause of death by cancer in the world and h. pylori is classified as a type i human carcinogen by the world health organization. however, despite the high prevalence of infection by h. pylori around the world, less than 3% of individuals carrying the bacteria develop gastric neoplasias. such a fact indicates that evolution towards malignancy may be associated with bacterial factors in the host and the environment.201121537542
prevalence of horb gene among the helicobacter pylori strains isolated from dyspeptic patients: first report from iran.helicobacter pylori (h. pylori) is globally accepted as an important cause of gastritis in human, and evidence strongly shows an etiological role for h. pylori in gastric cancer and peptic ulceration. in this study, we determined the relationship between digestive diseases and the horb gene of h. pylori infection. fresh antral biopsy specimens were obtained from 140 dyspeptic patients (67 men and 73 women; mean age 41.5, aged 19-63 years). they were examined for presence of the horb gene of h. p ...201121559747
[morphological characteristics of duodenum mucosa in children with atopic dermatitis].the results of investigation of 87 children suffering from chronic gastroduodenitis and atopic dermatitis are presented. all the child underwent fibrogastroduodenoscopy with duodenal mucosal biopsy and diagnostics of helicobacter pylori infection, lambliasis. hystomorphological and immunohystochemical studies of mucosal biopsy specimens for epstein - barr virus were carried out. the role of atopy and infection factors in genesis of chronic gastroduodenitis was evaluated.201121560389
protease activity of the api2-malt1 fusion oncoprotein in malt lymphoma development and treatment.gastric mucosa-associated lymphoid tissue (malt) lymphoma is a prototypical cancer that occurs in the setting of chronic inflammation and an important model for understanding how deregulated nf-κb transcriptional activity contributes to malignancy. most gastric malt lymphomas require ongoing antigenic stimulation for continued tumor growth, and stage i disease is usually cured by eradicating the causative microorganism, helicobacter pylori, with antibiotics. however, in a subset of malt lymphoma ...201121568677
redox biology and gastric carcinogenesis: the role of helicobacter pylori.almost half the world's population is infected by helicobacter pylori (h. pylori). this bacterium increases the production of reactive oxygen species (ros) and reactive nitrogen species (rns) in human stomach, and this has been reported to impact upon gastric inflammation and carcinogenesis. however, the precise mechanism by which h. pylori induces gastric carcinogenesis is presently unclear. although the main source of ros/rns production is possibly the host neutrophil, h. pylori itself produce ...201121605492
mucosal progranulin expression is induced by h. pylori, but independent of secretory leukocyte protease inhibitor (slpi) expression.abstract: background: mucosal levels of secretory leukocyte protease inhibitor (slpi) are specifically reduced in relation to h. pylori-induced gastritis. progranulin is an epithelial growth factor that is proteolytically degraded into fragments by elastase (the main target of slpi). considering the role of slpi for regulating the activity of elastase, we studied whether the h. pylori-induced reduction of slpi and the resulting increase of elastase-derived activity would reduce the progranulin p ...201121612671
anti-helicobacter pylori activity of fermented milk with lactic acid bacteria.ten strains of lactic acid bacteria (lab) were investigated for their anti-helicobacter pylori effects. the bactericidal activity and organic acid content in spent culture supernatants (scs) from fermented milk were measured. in addition, the exclusion effect of scs against h. pylori infection of human gastric epithelial ags cells was assayed.201121445876
increased expression of toll-like receptors (tlr) 2, 4 and 5 in gastric dysplasia.tlrs are important innate immunity receptors. even though tlr2, 4 and 5 appear to be important for helicobacter pylori (hp) recognition, their role in the evolution of gastritis to more advanced lesions is still unknown. to compare the expression of tlr2, 4 and 5 in normal gastric mucosa, hp+ gastritis, intestinal metaplasia, dysplasia and adenocarcinoma. immunohistochemistry for tlr2, 4 and 5 was performed with anti-tlr2-tlr4-tlr5 antibodies in 117 histological samples of normal gastric mucosa ...201121455638
the combination of serum trefoil factor 3 and pepsinogen testing is a valid non-endoscopic biomarker for predicting the presence of gastric cancer: a new marker for gastric cancer risk.a valid biomarker for predicting the presence of gastric cancer may contribute to reducing deaths from this disease. although pepsinogen (pg) testing has been introduced as a predictor, its predictive power is not satisfactory. we examined whether serum trefoil factor (tff) could be a non-endoscopic predictor of the presence of gastric cancer.201121455714
polymorphisms in the 3'-untranslated region of the cdh1 gene are a risk factor for primary gastric diffuse large b-cell lymphoma.primary gastric b-cell lymphomas arise from mucosa-associated lymphatic tissue (malt) in patients with chronic helicobacter pylori infection. we investigated whether germline variants in the cdh1 gene, coding for e-cadherin, genetically predispose patients to primary gastric b-cell lymphoma.201121459793
cholesterol enhances helicobacter pylori resistance to antibiotics and ll-37.the human gastric pathogen helicobacter pylori steals host cholesterol, modifies it by glycosylation, and incorporates the glycosylated cholesterol onto its surface via a cholesterol glucosyltransferase, encoded by cgt. the impact of cholesterol on h. pylori antimicrobial resistance is unknown. h. pylori strain 26695 was cultured in ham's f12 chemically defined medium in the presence or absence of cholesterol. the two cultures were subjected to overnight incubations with serial 2-fold dilutions ...201121464244
molecular cross-talk between helicobacter pylori and human gastric mucosa.helicobacter pylori (h. pylori) has co-evolved with humans to be transmitted from person to person and to colonize the stomach persistently. a well-choreographed equilibrium between the bacterial effectors and host responses permits microbial persistence and health of the host, but confers a risk for serious diseases including gastric cancer. during its long coexistence with humans, h. pylori has developed complex strategies to limit the degree and extent of gastric mucosal damage and inflammati ...201121472096
helicobacter pylori vaca induces programmed necrosis in gastric epithelial cells.helicobacter pylori is a gram-negative bacterium that colonizes the human stomach and contributes to the development of peptic ulcer disease and gastric cancer. the secreted pore-forming toxin vaca is one of the major virulence factors of h. pylori. in the current study, we show that az-521 human gastric epithelial cells are highly susceptible to vaca-induced cell death. wild-type vaca causes death of these cells, whereas mutant vaca proteins defective in membrane channel formation do not. incub ...201121482684
association between alcohol intake and risk for gastric cancer with regard to aldh2 genotype in the korean population.background: the relationship between alcohol intake and the risk for gastric cancer is not fully understood. the association between alcohol consumption and the risk for gastric cancer was investigated in the korean population with the aldh2 genotype. methods: from 2003 to 2008, 445 patients with gastric cancer and 370 control subjects ≥50 years of age were included in the analysis. logistic regression models including age, gender, education, smoking and drinking status, helicobacter pylori infe ...201121507992
association between genetic polymorphisms related to dna repair or xenobiotic pathways and gastric premalignant conditions.genetic factors related to dna repair or xenobiotic pathways might confer different degrees of susceptibility to helicobacter pylori (h. pylori)-related gastric carcinogenesis. the association between xrcc1 arg399gln, and arg194trp, gstp1 ile104val, and gstt1, gstm1 null polymorphisms with gastric intestinal metaplasia, severity of histological gastritis, and peptic ulcer diseases were evaluated in a japanese population.201121508403
increased genetic susceptibility to intestinal-type gastric cancer is associated with increased activity of the runx3 distal promoter.background: the runt-related transcription factor runx3 plays essential roles in various types of tumors, including gastric cancer. epigenetic changes in the methylation of the runx3 proximal promoter, but not common genetic changes in runx3, have been associated with both changes in the gene expression and development of the cancer. methods: a case-control association study was conducted by genotyping 865 unrelated korean subjects. subsequent functional studies were performed to reveal function ...201121523770
knockdown of ezrin via rna interference suppresses helicobacter pylori-enhanced invasion of gastric cancer cells.h. pylori interacts with gastric epithelial cells, which may activate signaling pathways important for gastric cancer invasion. ezrin, a membrane cytoskeletal crosslinker protein, is well documented to regulate cell adhesion and cell motility. the aim of the present study was to determine whether ezrin is involved in h. pylori-induced cancer cell motility and invasion.201121282970
cd25high tregs and pd-1 expression on gastric infiltrating cd4+ t lymphocytes in patients with helicobacter pylori infection.we observed by flow cytometry that the frequency of both gastric infiltrating tregs and pd-1 positive cd4 t cells is correlated with the density of h. pylori, suggesting that cellular immunity is inhibited against this pathogen.201121562113
chepep controls helicobacter pylori infection of the gastric glands and chemotaxis in the epsilonproteobacteria.abstract microbes use directed motility to colonize harsh and dynamic environments. we discovered that helicobacter pylori strains establish bacterial colonies deep in the gastric glands and identified a novel protein, chepep, necessary to colonize this niche. chepep is preferentially localized to the flagellar pole. although mutants lacking chepep have normal flagellar ultrastructure and are motile, they have a slight defect in swarming ability. by tracking the movement of single bacteria, we f ...201121791582
esophageal adenocarcinoma developing after eradication of helicobacter pylori.a 75-year-old man underwent endoscopic hemostatic therapy for hemorrhagic gastric ulcer in september 2002. after healing of the gastric ulcer, he underwent helicobacter pylori eradication therapy in february 2003. in august 2007, an irregular tumor was detected in the lower esophagus at annual checkup for gastric cancer screening using x-ray. endoscopic examination showed that the lower margin of the tumor almost coincided with the esophagogastric junction and that a short segment of barrett's e ...201121769287
stress-induced hemorrhagic gastric ulcer after successful helicobacter pylori eradication: two case reports.abstract:201121714884
unexpected role for helicobacter pylori dna polymerase i as a source of genetic variability.helicobacter pylori, a human pathogen infecting about half of the world population, is characterised by its large intraspecies variability. its genome plasticity has been invoked as the basis for its high adaptation capacity. consistent with its small genome, h. pylori possesses only two bona fide dna polymerases, pol i and the replicative pol iii, lacking homologues of translesion synthesis dna polymerases. bacterial dna polymerases i are implicated both in normal dna replication and in dna rep ...201121731507
high levels of soluble herpes virus entry mediator in sera of gastric cancer patients.the development of gastric cancer (gc) is closely related to chronic inflammation caused by helicobacter pylori infection, and herpes virus entry mediator (hvem) is a receptor expressed on the surface of leukocytes that mediates potent inflammatory responses in animal models. however, the role of hvem in human gc has not been studied. previously, we showed that the interaction of hvem on human leukocytes with its ligand light induces intracellular calcium mobilization, which results in inflammat ...201122113134
Communicable diseases prioritized for surveillance and epidemiological research: results of a standardized prioritization procedure in Germany, 2011.To establish strategic priorities for the German national public health institute (RKI) and guide the institute's mid-term strategic decisions, we prioritized infectious pathogens in accordance with their importance for national surveillance and epidemiological research.201121991334
use of real-time, label-free analysis in revealing low-affinity binding to blood group antigens by helicobacter pylori.infectious diseases are often initiated by microbial adherence that is mediated by the binding of attachment molecules, termed adhesins, to cell surface receptors on host cells. we present an experimental system, oblique-incidence reflectivity difference (oi-rd) microscopy, which allows the detection of novel, low-affinity microbial attachment mechanisms that may be essential for infectious processes. oi-rd microscopy was used to analyze direct binding of the oncopathogen, helicobacter pylori ( ...201121721569
novel short amp: design and activity study.in a previous study, we reported that truncation of hp (2-20) (derived from the n-terminal region of helicobacter pylori ribosomal protein l1 (rpl1)) at the n- (residues 2-3) and c-terminal (residues 17-20) truncated fragments to give hp (4-16) induces increased antibiotic activity against several bacterial strains without hemolysis. in this study, to develop novel short antibiotic peptides useful as therapeutic drugs, an analogue was designed to possess increased hydrophobicity by trp substitut ...201121838696
Exploiting bacterial glycosylation machineries for the synthesis of a Lewis antigen-containing glycoprotein.Glycoproteins constitute a class of compounds of increasing importance for pharmaceutical applications. The manipulation of bacterial protein glycosylation systems from Gram-negative bacteria for the synthesis of recombinant glycoproteins is a promising alternative to the current production methods. Proteins carrying Lewis antigens have been shown to have potential applications for the treatment of diverse autoimmune diseases. In this work, we developed a mixed approach consisting of in vivo and ...201121878645
Identification of Helicobacter pylori in Skin Biopsy of Prurigo Pigmentosa.A 23-year-old Chinese man presented with a 3-year history of a pruritic eruption. On examination, pink urticarial papules associated with hyperpigmented reticulated patches were noted on his neck, back, and upper chest. Histopathology revealed vacuolar interface dermatitis and numerous gram-negative rods within a dilated hair follicle. The organisms were reactive with anti-Helicobacter pylori immunohistochemisty. The histologic findings and clinical presentation support the diagnosis of prurigo ...201122197863
[jianpi jiedu recipe inhibited helicobacter pylori-induced the expression of cyclooxygenase-2 via p38mapk/atf-2 signal transduction pathway in human gastric cancer cells].to study the effect of jianpi jiedu recipe (jjr) on the expression of cyclooxygenase (cox-2) in helicobacter pylori (hp) infected gastric cancer cell line mkn 45, and its regulatory mechanism of p38mapk signal transduction.201121866663
The genome-wide expression profile of gastric epithelial cells infected by naturally occurring cagA isogenic strains of Helicobacter pylori.Helicobacter pylori (H. pylori) is associated with the development of gastric adenocarcinoma and lymphoma. However, the mechanisms through which H. pylori induces gastric mucosal lesions are not well defined. This study was conducted to evaluate the effect of the oncoprotein CagA on gastric cancer cells using whole-genome expression arrays. Human gastric epithelial (AGS) cells were incubated with CagA-positive H. pylori strains (147C (phosphorylated CagA) or 147A (dephosphorylated CagA)), and to ...201122004957
helicobacter felis--associated gastric disease in microbiota-restricted mice.human helicobacter pylori infection leads to multiple pathological consequences, including gastritis and adenocarcinoma. although this association has led to the classification of h. pylori as a type 1 carcinogen, it is not clear if additional nonhelicobacter gastric microbiota play a role in these diseases. in this study, we utilized either specific pathogen-free c57bl/6 mice (b6.spf) or mice colonized with altered schaedler flora (b6.asf) to evaluate the role of nonhelicobacter gastric microbi ...201121852692
genetic factors influence serological measures of common infections.antibodies against infectious pathogens provide information on past or present exposure to infectious agents. while host genetic factors are known to affect the immune response, the influence of genetic factors on antibody levels to common infectious agents is largely unknown. here we test whether antibody levels for 13 common infections are significantly heritable.201121996708
ulcerogenic helicobacter pylori strains isolated from children: a contribution to get insight into the virulence of the bacteria.infection with helicobacter pylori is the major cause for the development of peptic ulcer disease (pud). in children, with no other etiology for the disease, this rare event occurs shortly after infection. in these young patients, habits of smoking, diet, consumption of alcohol and non-steroid anti-inflammatory drugs and stress, in addition to the genetic susceptibility of the patient, represent a minor influence. accordingly, the virulence of the implicated h. pylori strain should play a crucia ...201122039453
assembly of preactivation complex for urease maturation in helicobacter pylori: crystal structure of uref-ureh protein complex.colonization of helicobacter pylori in the acidic environment of the human stomach depends on the neutralizing activity of urease. activation of apo-urease involves carboxylation of lysine 219 and insertion of two nickel ions. in h. pylori, this maturation process involves four urease accessory proteins as follows: uree, uref, ureg, and ureh. it is postulated that the apo-urease interacts with uref, ureg, and ureh to form a pre-activation complex that undergoes gtp-dependent activation of urease ...201122013070
cure of alopecia areata after eradication of helicobacter pylori: a new association?alopecia areata is a disease of the hair follicles, with strong evidence supporting autoimmune etiology. alopecia areata is frequently associated with immune-mediated diseases with skin manifestations such as psoriasis and lichen planus, or without skin manifestations such as autoimmune thyroiditis and idiopathic thrombocytopenic purpura. helicobacter pylori (h. pylori) infection is present in around 50% of the world's population and has been associated with a variety of immune-mediated extra-di ...201121912461
Lack of association between gene polymorphisms of Angiotensin converting enzyme, Nod-like receptor 1, Toll-like receptor 4, FAS/FASL and the presence of Helicobacter pylori-induced premalignant gastric lesions and gastric cancer in Caucasians.Several polymorphisms of genes involved in the immunological recognition of Helicobacter pylori and regulating apoptosis and proliferation have been linked to gastric carcinogenesis, however reported data are partially conflicting. The aim of our study was to evaluate potential associations between the presence of gastric cancer (GC) and high risk atrophic gastritis (HRAG) and polymorphisms of genes encoding Angiotensin converting enzyme (ACE), Nod-like receptor 1 (NOD1), Toll-like receptor 4 (T ...201121864388
[Complete remission of diffuse large B-cell lymphoma of the stomach after eradication of Helicobacter pylori].A 91 year-old man was found to have diffuse large cell B-cell lymphoma (DLBCL), localized to the stomach. Because of his age, his only treatment was anti-Helicobacter pylori therapy. He achieved a complete remission, and six months after the initial presentation, there were no signs of recurrence. The recommended treatment of DLBCL is chemotherapy followed by involved-field irradiation. However, small prospective trials have shown high rates of complete remission after eradication of H. pylori a ...201121958489
induction of cd69 expression by cagpai-positive helicobacter pylori infection.to investigate and elucidate the molecular mechanism that regulates inducible expression of cd69 by helicobacter pylori (h. pylori) infection.201121990950
mir-449 inhibits cell proliferation and is down-regulated in gastric cancer.gastric cancer is the fourth most common cancer in the world and the second most prevalent cause of cancer related death. the development of gastric cancer is mainly associated with h. pylori infection leading to a focus in pathology studies on bacterial and environmental factors, and to a lesser extent on the mechanistic development of the tumour. micrornas are small non-coding rna molecules involved in post-transcriptional gene regulation. they are found to regulate genes involved in diverse b ...201121418558
curcumin alleviates matrix metalloproteinase-3 and -9 activities during eradication of helicobacter pylori infection in cultured cells and mice.current therapy-regimens against helicobacter pylori (hp) infections have considerable failure rates and adverse side effects that urge the quest for an effective alternative therapy. we have shown that curcumin is capable of eradicating hp-infection in mice. here we examine the mechanism by which curcumin protects hp infection in cultured cells and mice. since, mmp-3 and -9 are inflammatory molecules associated to the pathogenesis of hp-infection, we investigated the role of curcumin on inflamm ...201121283694
infection with the carcinogenic human liver fluke, opisthorchis viverrini.throughout southeast asia there is a strikingly high incidence of cholangiocarcinoma (cca--hepatic cancer of the bile duct epithelium), particularly in people from rural settings in laos and northeast thailand who are infected with the liver fluke, opisthorchis viverrini, one of only three carcinogenic eukaryotic pathogens. more ubiquitous carcinogenic microbes, such as helicobacter pylori, induce cancer in less than 1% of infected people, while as many as one-sixth of people with opisthorchiasi ...201121311794
methods to evaluate alterations in polyamine metabolism caused by helicobacter pylori infection.helicobacter pylori is a gram-negative bacteria that infects the human stomach of half of the world's -population. colonization is followed by infiltration of the gastric mucosa by lymphocytes and myeloid cells. these cells are activated by various bacterial factors, causing them to produce immune/inflammatory mediators, including reactive nitrogen species and polyamines that contribute to cellular damage and the pathogenesis of h. pylori-associated gastric cancer. in vitro experiments have reve ...201121318889
determination of volatile organic compounds in human breath for helicobacter pylori detection by spme-gc/ms.helicobacter pylori living in the human stomach release volatile organic compounds (vocs) that can be detected in expired air. the aim of the study was the application of breath analysis for bacteria detection. it was accomplished by determination of vocs characteristic for patients with h. pylori and the analysis of gases released by bacteria in suspension. solid-phase microextraction was applied as a selective technique for preconcentration and isolation of analytes. gas chromatography coupled ...201121321973
the characterization of helicobacter pylori dna associated with ancient human remains recovered from a canadian glacier.helicobacter pylori is a gram-negative bacterium that colonizes the stomach of nearly half of the world's population. genotypic characterization of h. pylori strains involves the analysis of virulence-associated genes, such as vaca, which has multiple alleles. previous phylogenetic analyses have revealed a connection between modern h. pylori strains and the movement of ancient human populations. in this study, h. pylori dna was amplified from the stomach tissue of the kwäday dän ts'ìnchi individ ...201121359221
editorial foreword for the special issue "infection and human cancer". "infection and human cancer: disclosing the biology of cancer and beyond". 201121397391
tumor promoters--microcystin-lr, nodularin and tnf-a and human cancer development.microcystin-lr and nodularin, along with okadaic acid, are potent inhibitors of protein phosphatases 1 and 2a (pp1 and pp2a). the mechanisms of action of microcystin-lr and nodularin in the liver and that of okadaic acid, a potent tumor promoter on mouse skin, have attracted the attention of the scientists. this paper reviews several topics: new inhibitors of pp1 and pp2a with new chemical structures, structure-function relationships for both receptor binding and inhibition of protein phosphatas ...201121269254
tribbles 3: a novel regulator of tlr2-mediated signaling in response to helicobacter pylori lipopolysaccharide.helicobacter pylori causes chronic gastritis, peptic ulcers, and gastric carcinoma. gastric epithelial cells provide the first point of contact between h. pylori and the host. tlrs present on these cells recognize various microbial products, resulting in the initiation of innate immunity. although previous reports investigated tlr signaling in response to intact h. pylori, the specific contribution of h. pylori lps with regard to functional genomics and cell-signaling events has not been defined ...201121220698
[etiology of atherosclerosis-- special reference to bacterial infection and viral infection].atherosclerosis is caused by multiple factors. infectious disease has been proposed to be one of the causative factors, and several bacteria and viruses have been studied for their correlations with atherosclerotic diseases; these organisms include chlamydia pneumoniae, helicobacter pylori, hiv, cmv, hsv and hepatitis viruses. many underlying mechanisms that infectious diseases cause atherosclerosis have been proposed; most of them suggested that inflammatory process provoked by infectious disea ...201121226255
evaluation of a new antigen for diagnosis of helicobacter pylori infection in stool of adult and children.nowadays, there is an increasing interest in noninvasive methods to diagnose helicobacter pylori infection. indeed, they can profitably replace endoscopy in predicting the diagnosis. the stool antigen test for h. pylori is a noninvasive immunoassay to diagnose active infection with this bacterium in human fecal samples. the aim of this study was detection of alkyl hydroperoxide reductase protein (ahpc) antigen by immunoblotting in stool samples for diagnosis of h. pylori.201121241411
role of dna methylation in the development of diffuse-type gastric cancer.cancer cells exhibit two opposing methylation abnormalities: genome-wide hypomethylation and gene promoter hypermethylation. downregulation of e-cadherin (cdh1) plays a key role in the development of diffuse-type gastric cancer, and dna methylation is a major cause of the gene's silencing. hereditary diffuse gastric cancer is caused by germline mutation of cdh1 gene, and dna methylation frequently serves as the second hit completely inactivating the gene. in sporadic diffuse-type gastric cancer, ...201121273772
helicobacter pylori and gastritis: untangling a complex relationship 27 years on.since its' introduction by warren and marshall 27 years ago, helicobacter pylori (hp) has become the linchpin in our understanding of important gastric conditions including gastritis, intestinal metaplasia (im), gastric/duodenal ulcers (gu/du), mucosal associated lymphoid tumour (maltoma) and gastric cancer. initially named campylobacter pyloridis, it was re-named hp when biochemical and genetic characterization of the organism showed that it was not a member of the campylobacter genus. the find ...201121199513
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