| pharmacogenetics of esomeprazole or rabeprazole-based triple therapy in helicobacter pylori eradication in hong kong non-ulcer dyspepsia chinese subjects. | our study aimed to assess the effectiveness of esomeprazole or rabeprazole in combination with amoxicillin and clarithromycin for the eradication of helicobacter pylori in hong kong non-ulcer dyspepsia (nud) patients. | 2010 | 20831535 |
| muc1 expression and its association with other aetiological factors and localization to mitochondria in preneoplastic and neoplastic gastric tissues. | the molecular events that underlie the conversion of normal human gastric epithelium into adenocarcinoma are poorly understood. muc1 overexpression and localization in mitochondria might confer cancer cells with attenuation of stress induced apoptosis. we studied muc1 expression pattern, interaction with hsp70 and localization in mitochondria in preneoplastic and neoplastic human gastric tissues. | 2010 | 20832392 |
| detection of helicobacter rodentium-like dna in the liver tissue of patients with chronic liver diseases by polymerase chain reaction-denaturing gradient gel electrophoresis and dna sequence analysis. | many helicobacter spp. were isolated from the stomach, intestinal tract, and liver of different animals and humans. the association between helicobacter spp. and hepatobiliary diseases, including hepatocellular carcinoma, was thoroughly examined, indicating a potential role of the bacteria in the progression toward cancer. in our work, we screened 97 liver biopsies from patients with chronic liver diseases for the presence of helicobacter spp. dna. with the use of genus-specific polymerase chain ... | 2010 | 20850251 |
| structure and immunomodulatory property relationship in napa of borrelia burgdorferi. | napa from borrelia burgdorferi is a member of the dps-like protein family with specific immunomodulatory properties; in particular, napa is able to induce the expression of il-23 in neutrophils and monocytes, as well as the expression of il-6, il-1β, and transforming growth factor beta (tgf-β) in monocytes, via toll-like receptor (tlr) 2. such an activity on innate immune cells triggers a synovial fluid th17 response. here we report the crystal structure of napa, determined at 2.6å resolution, w ... | 2010 | 20851780 |
| il23r +2199a/c polymorphism is associated with decreased risk of certain subtypes of gastric cancer in chinese: a case-control study. | today, the causal relationship between inflammation and gastric cancer is more widely accepted. genetic variations in inflammation-related genes especially cytokines and their receptors, were thought to partly determine the outcome of helicobacter pylori (h. pylori) infection and progression of gastric lesions. interleukin 23 receptor (il23r), as a key cytokine receptor gene in the important inflammatory il-17/il-23 axis, may contribute to gastric cancer predisposition. up till now, the associat ... | 2010 | 20863779 |
| online immunoaffinity assay-ce using magnetic nanobeads for the determination of anti-helicobacter pylori igg in human serum. | about two-thirds of the world's population is infected with helicobacter pylori (h. pylori). this gram-negative bacterium is the most important etiological agent of chronic active type b gastritis and peptic ulcer diseases. conventional methods such as gastric biopsy, elisa and culture, require a long time for the determination of h. pylori infections. moreover, the antibodies in human serum sample are capable to react immunologically with the purified h. pylori antigens immobilized on different ... | 2010 | 20922758 |
| significant increase in igg4+ plasma cells in gastric biopsy specimens from patients with pernicious anaemia. | to investigate the presence of igg4+ plasma cells in gastric mucosal biopsy samples from patients with atrophic gastritis (ag) and a history of pernicious anaemia (pa) (ag+pa+). | 2010 | 20924031 |
| methylation-associated silencing of microrna-34b/c in gastric cancer and its involvement in an epigenetic field defect. | altered expression of microrna (mirna) is strongly implicated in cancer, and recent studies have shown that the silencing of some mirnas is associated with cpg island hypermethylation. to identify epigenetically silenced mirnas in gastric cancer (gc), we screened for mirnas induced by treatment with 5-aza-2'-deoxycytidine and 4-phenylbutyrate. we found that mir-34b and mir-34c are epigenetically silenced in gc and that their downregulation is associated with hypermethylation of the neighboring c ... | 2010 | 20924086 |
| helicobacter pylori vaca reduces the cellular expression of stat3 and pro-survival bcl-2 family proteins, bcl-2 and bcl-xl, leading to apoptosis in gastric epithelial cells. | helicobacter pylori vacuolating cytotoxin, vaca, stimulates apoptosis via a mitochondria-dependent pathway. vaca induces apoptosis via activation of the pro-apoptotic b-cell lymphoma (bcl)-2 family proteins, bcl-2-associated x protein (bax) and bcl-2 homologous antagonist/killer (bak), while the implication of such pro-survival bcl-2 family members as bcl-2 and bcl-xl in the vaca-induced apoptosis remains unknown. signal transduction and activator of transcription 3 (stat3) is a pivotal transcri ... | 2010 | 20927590 |
| anthropological and clinical implications for the structural diversity of the helicobacter pylori caga oncoprotein. | helicobacter pylori caga is the first bacterial oncoprotein to be identified in relation to human cancer. caga is delivered into gastric epithelial cells through a bacterial type iv secretion system and localizes to the plasma membrane, where it undergoes tyrosine phosphorylation by host cell kinases. membrane-localized caga then mimics mammalian scaffold proteins and perturbs a number of host signaling pathways in both tyrosine phosphorylation-dependent and -independent manners, thereby promoti ... | 2010 | 20942897 |
| 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 ... | 2010 | 20957490 |
| k-ras mutation targeted to gastric tissue progenitor cells results in chronic inflammation, an altered microenvironment, and progression to intraepithelial neoplasia. | chronic infectious diseases, such as helicobacter pylori infection, can promote cancer in a large part through induction of chronic inflammation. oncogenic k-ras mutation in epithelial cells activates inflammatory pathways, which could compensate for a lack of infectious stimulus. gastric histopathology and putative progenitor markers [doublecortin and calcium/calmodulin-dependent protein kinase-like 1 (dcamkl1) and keratin 19 (k19)] in k19-k-ras-v12 (k19-kras) transgenic mice were assessed at 3 ... | 2010 | 20959488 |
| 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 ... | 2010 | 20969490 |
| 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 ... | 2010 | 21035731 |
| 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 ... | 2010 | 21054656 |
| 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 ... | 2010 | 21038469 |
| 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 ... | 2010 | 21049552 |
| 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 ... | 2010 | 21054464 |
| [detection of caga prevalence in clinical isolates of helicobacter pylori.] | helicobacter pylori is a gram-negative, microaerophilic bacterium that colonizes human gastric mucosa and affects approximately 50% of the whole world population. it has put the blame on gastric ulcer, duodenal ulcer, chronic atrophic gastritis, mucosa-associated lymphoid tissue lymphoma and stomach adenocarcinoma, as the etiological agent. the caga (cytotoxin-associated gene a) gene which is one of the most important virulence factors of h.pylori, encodes a 120-145 kda protein called caga antig ... | 2010 | 21063996 |
| virulence factor cytotoxin-associated gene a in helicobacter pylori is downregulated by interferon-γin vitro. | helicobacter pylori-infected gastric mucosa is characterized by high levels of interferon-γ (ifn-γ), but whether the high level of ifn-γ regulates the virulence of h. pylori is unclear. here, we characterized the response of h. pylori to ifn-γ and found by indirect immunofluorescence that ifn-γ can bind to h. pylori. the binding resulted in the altered expression of 14 proteins, including the virulence factor, cytotoxin-associated gene a (caga), whose expression was downregulated. the transcript ... | 2010 | 21070385 |
| microbial and viral pathogens in colorectal cancer. | the heterogenetic and sporadic nature of colorectal cancer has led to many epidemiological associations with causes of this disease. as our understanding of the underlying molecular processes in colorectal-cancer develops, the concept of microbial-epithelial interactions as an oncogenic trigger might provide a plausible hypothesis for the pathogenesis of colorectal cancer. by contrast with other cancers of the gastrointestinal tract (gastric carcinoma, mucosa-associated lymphoid-tissue lymphoma) ... | 2010 | 21067973 |
| helicobacter pylori induction of the gastrin promoter through gc-rich dna elements. | helicobacter pylori (h. pylori) infection has been linked to the development of chronic gastritis, duodenal ulcer disease, and gastric cancer. helicobacter pylori- infected patients and animal models develop hypergastrinemia, chronic gastritis, and gastric atrophy. since gastrin is an important regulator of gastric acid secretion and cell growth, h. pylori regulation of this hormone has been implicated in its pathogenesis. | 2010 | 21083750 |
| [carcinogenic mechanisms of helicobacter pylori]. | | 2009 | 21089532 |
| helicobacter pylori affects the cellular deubiquitinase usp7 and ubiquitin-regulated components traf6 and the tumour suppressor p53. | helicobacter pylori is a recognized cancerogenic bacterial agent in humans, associated with gastritis, peptic ulcer, and gastric cancer. immunoevasive and immunomodulatory mechanisms underlie the chronic persistence of the bacterium and the active proinflammatory effect of life-long h. pylori infection. in contrast to tumorigenic viruses, which frequently possess factors to influence the host ubiquitin-proteasome system (ups), nothing is yet known about potential effects of h. pylori in this res ... | 2010 | 21131231 |
| optimizing the growth of stressed helicobacter pylori. | helicobacter pylori is a gram-negative bacterium that colonizes the human stomach and is responsible for causing gastric ulcers. h. pylori is known to become stressed and nonculturable after exposure to unfavorable conditions. in this study, we enhanced previously published resuscitation procedures, characterized conditions under which stressed h. pylori can be recovered, and formulated a selective and differential resuscitation medium. results showed that a specialized broth supplemented with t ... | 2010 | 21129415 |
| personalized treatment in the eradication therapy for helicobacter pylori. | helicobacter pylori (hp) is known to be a causative bacterium of gastritis and peptic ulcers. the combination treatment consisting of a proton pump inhibitor (ppi), amoxicillin and clarithromycin (cam) is widely used in eradication therapy, but the eradication fails in some patients. the main causes are cam resistance of hp and individual variability in ppi metabolism related to the activity of the cytochrome p450 2c19 (cyp2c19) enzyme. in this study, we examined the usefulness of the prediction ... | 2010 | 21132257 |
| 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 ... | 2010 | 21148572 |
| runx3 methylation and expression associated with advanced precancerous gastric lesions in a chinese population. | runt-related transcription factor 3 (runx3) is a tumor suppressor of gastric cancer. our study aimed to investigate the correlation of runx3 methylation, expression and the risk of advanced gastric lesions, based on a high-risk population in linqu county, shandong province, china. methylation status of runx3 was determined by methylation-specific polymerase chain reaction, and expression was detected by immunohistochemical analysis in 1113 subjects with different gastric lesions. results showed ... | 2010 | 21135153 |
| vitamin b(6) is required for full motility and virulence in helicobacter pylori. | despite recent advances in our understanding of how helicobacter pylori causes disease, the factors that allow this pathogen to persist in the stomach have not yet been fully characterized. to identify new virulence factors in h. pylori, we generated low-infectivity variants of a mouse-colonizing h. pylori strain using the classical technique of in vitro attenuation. the resulting variants and their highly infectious progenitor bacteria were then analyzed by global gene expression profiling. the ... | 2010 | 21151756 |
| the gastrointestinal aspects of halitosis. | halitosis is a common human condition for which the exact pathophysiological mechanism is unclear. it has been attributed mainly to oral pathologies. halitosis resulting from gastrointestinal disorders is considered to be extremely rare. however, halitosis has often been reported among the symptoms related to helicobacter pylori infection and gastroesophageal reflux disease. | 2010 | 21152460 |
| partial regression of duodenal lesions of intestinal follicular lymphoma after antibiotic treatment. | a 51-year-old man was referred to our hospital because of duodenal lesions of lymphoma. endoscopy showed multiple tiny smooth whitish granules in the second portion of the duodenum including the papilla of vater. biopsy specimens showed medium-sized centrocyte-like cells forming lymphoid follicles, and immunohistology showed positive staining for bcl-2 and cd10. a small bowel series showed multiple granular lesions extending from the second portion of the duodenum to the proximal jejunum and the ... | 2010 | 21175486 |
| helicobacter pylori defines local immune response through interaction with dendritic cells. | the bacterial pathogen helicobacter pylori colonizes the human gastric and duodenal mucosa, evades clearance by the host response and is associated with peptic ulcer disease and an increased risk of gastric adenocarcinoma. dendritic cells (dcs) are initiators of the immune response to h. pylori. the aim of the current study was to investigate the interaction between h. pylori with dcs. to determine the impact of h. pylori on the maturation and the activation of monocyte-derived dcs, the effect o ... | 2010 | 21175878 |
| helicobacter pylori: pathological mechanism involved in gastric colonization. | since 1982, when marshall and warren highlighted the presence of h. pylori at the apical pole of the epithelial gastric cells, the medical literature has registered a cascade of subsequent researches concerning this amazing bacterium, its action on the human body and the body response. the apogee of these studies and conclusions about the pathogenic role of hp was touched with its certain recognition as class one carcinogenic agent (peura 1997, who), becoming the first bacteria with such an acti ... | 2009 | 21179915 |
| 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 ... | 2011 | 21220698 |
| biochemical studies on helicobacter pylori arginase: insight into the difference in activity compared to other arginases. | arginase is a binuclear mn(2+)-metalloenzyme of urea cycle that catalyzes the conversion of l-arginine to l-ornithine and urea. unlike other arginases, the helicobacter pylori enzyme is selective for co(2+), and has lower catalytic activity. to understand the differences in the biochemical properties as well as activity compared to other arginases, we carried out a detailed investigation of different metal reconstituted h. pylori arginases that includes steady-state kinetics, fluorescence measur ... | 2010 | 21190293 |
| helicobacter pylori and inflammation. | helicobacter pylori is a spiral-shaped, flagellated, microaerophilic gram-negative bacillus which colonizes the gastric mucosa of more than 50% of human population. the chronic infection generates a state of inflammation, which however is asymptomatic in the majority of the subjects. nevertheless, in a subset of the h. pylori-infected population, the gastric inflammation may evolve toward chronic gastritis, peptic ulcer, gastric mucosa-associated lymphoid tissue (malt) lymphoma, and gastric canc ... | 2010 | 21184659 |
| 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 ... | 2011 | 21199513 |
| [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 ... | 2011 | 21226255 |
| 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. | 2011 | 21241411 |
| 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 ... | 2011 | 21283694 |
| 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 ... | 2011 | 21269254 |
| 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. | 2011 | 21282970 |
| 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, ... | 2011 | 21273772 |
| 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 ... | 2011 | 21311794 |
| 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 ... | 2011 | 21318889 |
| 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. ... | 2011 | 21352491 |
| host responses to h. pylori : molecular analysis of cytokine gene expression. | the interactions between helicobacter pylori and the human gastric epithelium have been modeled in an in vitro cell culture system. the model permits investigation of the interplay between the bacteria and epithelial cells in a controled environment. following coculture, the cells, bacteria, and culture supernatants are available for analysis. | 1997 | 21351036 |
| 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 ... | 2011 | 21321973 |
| pcr for the detection of h. pylori in gastric juice aspirates and environmental water samples. | helicobacter pylori is a curved gram-negative bacillus that infects the human gastric mucosa. most methods used to diagnose h. pylori require the collection of gastric samples by biopsy during gastroduodenoscopy. a positive culture or visualization of the organism by histologic examination of biopsy material can give a definitive diagnosis (1). to make a diagnosis without gastroduodenoscopy, indirect tests, such as elisa or urea breath tests, must be relied on (2). the polymerase chain reaction ... | 1997 | 21351019 |
| 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 ... | 2011 | 21359221 |
| editorial foreword for the special issue "infection and human cancer". "infection and human cancer: disclosing the biology of cancer and beyond". | | 2011 | 21397391 |
| the dual therapy with 4 times daily dosing of rabeprazole and amoxicillin as the 3rd rescue regimen for eradication of h. pylori. | most of patients who are refractory to usual standard eradication therapies for h. pylori infection have rapid metabolizer genotype of cyp2c19 and are infected with resistant strains to several antimicrobial agents. however, most of h. pylori strains are sensitive to amoxicillin. we tested whether dual therapy with the 4 times daily dosing of rabeprazole and amoxicillin was effective as the 3rd rescue regimen for eradication of h. pylori. | 2010 | 21410079 |
| 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. | 2011 | 21435094 |
| 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 ... | 2011 | 21418558 |
| 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. | 2011 | 21445876 |
| 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 ... | 2011 | 21455638 |
| 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. | 2011 | 21455714 |
| 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 ... | 2011 | 21464244 |
| 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 ... | 2011 | 21472096 |
| 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. | 2011 | 21459793 |
| 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 ... | 2011 | 21507992 |
| 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. | 2011 | 21508403 |
| 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 ... | 2011 | 21482684 |
| 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. | 2011 | 21537542 |
| 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 ... | 2011 | 21523770 |
| 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 ... | 2011 | 21559747 |
| [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. | 2011 | 21560389 |
| 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. | 2011 | 21562113 |
| 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 ... | 2011 | 21568677 |
| 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 ... | 2011 | 21605492 |
| motility, chemotaxis, and flagella | for many pathogenic bacteria, flagellum-dependent motility and chemotaxis are crucial factors in the process of colonization of the host organism and establishment of a successful infection (reviewed in references 36 and 39). the flagella of helicobacter pylori have been extensively studied, and convincing evidence is available demonstrating the key role of these organelles in the colonization of the human gastric mucosa by this fastidious pathogen. experiments with gnotobiotic piglets have esta ... | 2001 | 21290725 |
| enterohepatic helicobacter species | most of the members of the genus
helicobacter do not normally colonize the gastric mucosa, but
instead thrive in the mucosal surfaces of the intestinal tract and/or the liver of
humans, other mammals, and birds. these enterohepatic helicobacter
species have features of ultrastructure and physiology in common with helicobacter pylori and the other gastric
helicobacter species, and have been the subject of several recent
... | 2001 | 21290746 |
| 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 ... | 2011 | 21612671 |
| regulation of urease for acid habitation | h. pylori shows a remarkable acid-resistance response to the gastric environment by a specialized means of utilizing an intracellular, neutral ph optimum urease. within the urease gene cluster it has a gene encoding an acid-activated urea channel, urei. instead of an acidic ph optimum urease suitable only for passage through the stomach, it has a neutral ph optimum urease that allows the cytoplasm to remain relatively neutral while the organism protects itself against acid by enhancing urea acce ... | 2001 | 21290728 |
| activation of type i ifn signaling by nod1 mediates mucosal host defense against helicobacter pylori infection. | infection of gastric epithelial cells with helicobacter pylori (h. pylori) induces a complex array of host protective immune responses. the best known are the adaptive t helper type 1 and type 17 responses that are induced in the gastric lamina propria by antigen-presenting cells via presentation of h. pylori antigens to cd4 (+) t cells. recently, it has become apparent that innate immune responses are also induced by h.pylori infection, both in epithelial cells and in underlying antigen-present ... | 2010 | 21637021 |
| 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 ... | 2011 | 21646455 |
| 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 ... | 2011 | 21791582 |
| 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 ... | 2011 | 21770035 |
| 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 ... | 2011 | 21769287 |
| stress-induced hemorrhagic gastric ulcer after successful helicobacter pylori eradication: two case reports. | abstract: | 2011 | 21714884 |
| 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 ... | 2011 | 21731507 |
| 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 ... | 2011 | 21838696 |
| 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 ( ... | 2011 | 21721569 |
| 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 ... | 2011 | 22113134 |
| 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 ... | 2011 | 21878645 |
| 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. | 2011 | 21991334 |
| [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. | 2011 | 21866663 |
| 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 ... | 2011 | 22197863 |
| 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 ... | 2011 | 22004957 |
| 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 ... | 2011 | 21852692 |
| 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. | 2011 | 21996708 |
| 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 ... | 2011 | 22013070 |
| 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 ... | 2011 | 22039453 |
| 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 ... | 2011 | 21912461 |
| [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 ... | 2011 | 21958489 |
| 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. | 2011 | 21990950 |
| 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 ... | 2011 | 21864388 |