| cutting edge: cyclooxygenase-2 activation suppresses th1 polarization in response to helicobacter pylori. | helicobacter pylori infection causes a th1-driven mucosal immune response. cyclooxygenase (cox)-2 is up-regulated in lamina propria mononuclear cells in h. pylori gastritis. because cox-2 can modulate th1/th2 balance, we determined whether h. pylori activates cox-2 in human pbmcs, and the effect on cytokine and proliferative responses. there was significant up-regulation of cox-2 mrna and pge(2) release in response to h. pylori preparations. addition of cox-2 inhibitors or an anti-pge(2) ab resu ... | 2003 | 14530307 |
| molecular mimicry of host structures by lipooligosaccharides of neisseria meningitidis: characterization of sialylated and nonsialylated lacto-n-neotetraose (galbeta1-4glcnacbeta1-3galbeta1-4glc) structures in lipooligosaccharides using monoclonal antibodies and specific lectins. | neisseria meningitidis lipooligosaccharides (loss) are classified into 12 immunotypes. most loss are heterogeneous in having a few components by sds-page analysis that differ antigenically and chemically. we have utilized a monoclonal antibody that recognizes lacto-n-neotetraose (lnnt) and the lectin, maackia amurensis leukoagglutinin (mal), which is specific for neunacalpha2-3galbeta1-4glcnac trisacchride sequence to characterize the 12 n. meningitidis loss. using the combination of elisa, sds- ... | 2001 | 14533820 |
| effect of helicobacter pylori eradicated therapy on water gastric emptying in patients with active duodenal ulcer. | it remains debatable if duodenal ulcer (du) or helicobacter pylori infection has a definite impact on human gastric emptying (ge). we explored the nature of water ge in active du patients before and after ulcer healing and the influence of h. pylori eradication on ge. | 2003 | 14535981 |
| induction of cyclooxygenase 2 by escherichia coli but not helicobacter pylori lipopolysaccharide in gastric epithelial cells in vitro. | cyclooxygenase 2 (cox-2) is an inducible enzyme that plays a key role in the synthesis of prostaglandins in response to inflammatory stimuli. it is expressed in the gastric mucosa as part of the response to infection with helicobacter pylori. the specific interaction between h. pylori and the gastric epithelium that results in cox-2 expression has not been identified. | 2003 | 14535998 |
| the muc5ac glycoprotein is the primary receptor for helicobacter pylori in the human stomach. | helicobacter pylori shows a characteristic tropism for the mucus-producing gastric epithelium. in infected patients, h. pylori colocalizes in situ with the gastric secretory mucin muc5ac. the carbohydrate blood-group antigen lewis b (leb) was deemed responsible for the adherence of h. pylori to the gastric surface epithelium. we sought to determine if muc5ac is the carrier of leb, and thus if muc5ac is the underlying gene product functioning as the main receptor for h. pylori in the stomach. | 2003 | 14535999 |
| inhibition of helicobacter pylori-induced nuclear factor-kappa b activation and interleukin-8 gene expression by ecabet sodium in gastric epithelial cells. | helicobacter pylori stimulates nuclear factor-kappa b (nf-kappa b) activation and chemokine interleukin-8 (il-8) expression in gastric epithelial cells. ecabet sodium (ecabet), a locally acting antiulcer drug, is known to have anti-h. pylori activity. however, there is little understanding of how ecabet induces anti-inflammatory activity in gastric epithelial cells infected with h. pylori. the aim of this study was to investigate the effects of ecabet on il-8 gene expression and nf-kappa b activ ... | 2003 | 14536001 |
| [relationship between helicobacter pylori infection and expression of c-myc, bcl-2, and bax protein in different gastric mucosa lesions]. | helicobacter pylori (hp) has been believed to be a carcinogen of gastric carcinoma. however, its mechanism was yet not clearly understood. this study was designed to investigate the relationship between hp infection and gastric epithelial cell proliferation as well as apoptosis in different gastric mucosa lesions and elucidate the probable mechanism of gastric carcinogenesis relating with hp infection. | 2003 | 14558945 |
| coexpression of helicobacter pylori's proteins caga and hspb induces cell proliferation in ags gastric epithelial cells, independently from the bacterial infection. | adenocarcinoma of the stomach is the second most common cause of cancer mortality in the world. the purpose of this study was to evaluate the potential role in carcinogenesis of two secreted helicobacter pylori's proteins, caga and hspb, both shown to increase the risk of gastric carcinoma in patients infected with h. pylori-positive strain. the effects of these two proteins on cell kinetics and the ability to selectively affect the expression of cell cycle-related proteins by transfection of a ... | 2003 | 14559823 |
| helicobacter pylori: pathogen and symbiont. | there are puzzles in defining the exact role of helicobacter pylori infection in humans. the bacterium, which is associated with human disease of the upper gastrointestinal tract, may otherwise exist as a commensal with probable symbiotic association in some human hosts. although virulence associated genes have been detected in some strains which explain their pathogenicity, their pathogenic effect and subsequent clinical manifestations seem to vary in different human populations or geographical ... | 2003 | 14567051 |
| [disturbance of intracellular signaling by helicobacter pylori infection]. | | 2003 | 14577356 |
| remission of severe anemia persisting for over 20 years after eradication of helicobacter pylori in cases of ménètrier's disease and atrophic gastritis: helicobacter pylori as a pathogenic factor in iron-deficiency anemia. | a man with a 20-year history of recurrent iron-deficiency anemia complicated by helicobacter pylori-positive ménètrier's disease was observed over a 10-year clinical course, during which time he was successfully treated for the anemia and a gastric helicobacter pylori (h. pylori) infection through eradication. considering the satisfactory therapeutic results in this case, we performed eradication therapy on another h. pylori-positive atrophic gastritis case with a 24-year history of iron-deficie ... | 2003 | 14606710 |
| [invasiveness and cytopathogenicity of helicobacter pylori in human cell culture]. | invasive and cytopathogenic properties of clinical strains of helicobacter pylori in the cell culture hep-2 have been studied. it has been established that h. pylori possesses high invasive and adhesive capacity. it has been shown that h. pylori takes considerable effect on the indices of mitotic activity, such as mitotic index (mi), level of pathogenic mitoses; it also stimulates the appearance of pathologies connected with the disturbance of mitotic apparatus and damage of chromosomes. h. pylo ... | 2003 | 14618781 |
| helicobacter pylori-induced homotypic phagosome fusion in human monocytes is independent of the bacterial vaca and cag status. | following reports that a vaca+cag+ toxigenic but not a vaca-cag- non-toxigenic helicobacter pylori strain induced homotypic phagosome fusion in murine macrophages, we addressed that phenomenon in human cells. mononuclear phagocytes and epitheloid cells were challenged with h. pylori strains of different vaca and cag genotypes and with vaca- and cag- isogenic mutants, and chased in the absence or presence of signal transduction modulators. electron microscopy revealed that, in monocytes: (i) homo ... | 2003 | 14641174 |
| effect of omeprazole 10 mg on intragastric ph in three different cyp2c19 genotypes, compared with omeprazole 20 mg and lafutidine 20 mg, a new h2-receptor antagonist. | omeprazole 10 mg is used as maintenance therapy for gastro-oesophageal reflux disease, but previous reports have not mentioned the potency of its acid suppression. | 2003 | 14653835 |
| micropneumatosis coexistent with helicobacter pylori and its improvement. | micropneumatosis intestinalis is the occurrence of gas-filled circular voids with diameter of 20-200 microns, not lined with epithelium. we report a 39-year-old man with superficial gastritis and helicobacter pylori infection who also had gastric, duodenal and colonic micropneumatosis. endoscopic biopsy after treatment for h. pylori gastritis showed no micropneumatosis in gastric, duodenal or colonic mucosal sections. we suggest that h. pylori may be one of the causative factors for micropneumat ... | 2003 | 14658539 |
| association of the presence of helicobacter in gallbladder tissue with cholelithiasis and cholecystitis. | the presence of helicobacter dna species has been investigated in the biliary epithelium of patients with biliary diseases. however, conflicting results have been observed that may have been due to the small number of subjects studied, difficulty in obtaining a healthy control group, absence of controlling for confounding factors, or differences among populations. therefore, we investigated the presence of helicobacter species by culture and nested pcr of 16s rrna genes in gallbladder tissue and ... | 2003 | 14662950 |
| api2-malt1 fusion gene in colorectal lymphoma. | the api2-malt1 fusion gene was originally identified from a t(11;18)(q21;q21) translocation, a specific chromosomal abnormality that is found in mucosa-associated lymphoid tissue (malt) lymphoma. gastric malt lymphomas positive for the api2-malt1 fusion gene do not respond to helicobacter pylori-eradication therapy, but otherwise, the incidence and clinicopathological behavior of colorectal malt lymphoma with this genetic abnormality are unclear. we examined the api2-malt1 fusion by multiplex rt ... | 2003 | 14681324 |
| high-dose rabeprazole/amoxicillin therapy as the second-line regimen after failure to eradicate h. pylori by triple therapy with the usual doses of a proton pump inhibitor, clarithromycin and amoxicillin. | some patients are refractory to the usual triple therapy for eradication of helicobacter pylori, consisting of a proton pump inhibitor, amoxicillin and clarithromycin, so there needs to be an alternative strategy for retreatment after failure to eradicate the infection. | 2003 | 14696516 |
| helicobacter pylori-induced epithelial cell signalling in gastric carcinogenesis. | helicobacter pylori represents a highly successful human microbial pathogen that infects the stomach of more than half of the world's population. h. pylori induces gastric inflammation, and the diseases that can follow such infection include chronic gastritis, peptic ulcers and, more rarely, gastric cancer. the reasons why a minority of patients with h. pylori develops gastric cancer could be related to differences in host susceptibility, environmental factors and the genetic diversity of the or ... | 2004 | 14700549 |
| analysis of geospecific markers for helicobacter pylori variants in patients from japan and nigeria by triple-locus nucleotide sequence typing. | human migrations and geographical separation over long periods may have resulted in ecologically distinct populations of helicobacter pylori infecting individuals in different continents. this study used nucleotide sequence analysis with the aim of defining population-specific genomic motifs in isolates from east asian and african dyspeptic patients. sequences of internal fragments (542-627 bp) of three housekeeping genes (urei, ahpc and atpa) were analysed for 85 isolates from individuals in ja ... | 2004 | 14702408 |
| effect of total secondary carotenoids extracts from chlorococcum sp on helicobacter pylori-infected balb/c mice. | helicobacter pylori is a human pathogen associated with type b gastritis, peptic ulcer disease and gastric cancer. a high intake of carotenoids has been suggested to prevent development of gastric malignancies. microalgae chlorococcum sp. could accumulate secondary carotenoids under stress conditions. the aim of the present study was to investigate whether dietary cell extract of chlorococcum sp. could affect the bacterial load of h. pylori infected balb/c mice and whether it could induce modula ... | 2003 | 12810355 |
| oxidative-stress-related proteome changes in helicobacter pylori-infected human gastric mucosa. | helicobacter pylori infection leads to gastroduodenal inflammation, peptic ulceration and gastric carcinoma. proteomic analysis of the human gastric mucosa from the patients with erosive gastritis, peptic ulcer or gastric cancer, which were either infected or not with h. pylori, was used to determine the differentially expressed proteins by h. pylori in the human gastric mucosa in order to investigate the pathogenic mechanism of h. pylori -induced gastric diseases. prior to the experiment, the e ... | 2004 | 14711373 |
| helicobacter pylori and gastroesophageal reflux disease. | since the rediscovery of helicobacter pylori two decades ago, it has become increasingly clear that the true relationships between this organism and diseases of the upper gastrointestinal tract are highly complex. h. pylori colonization is a strong risk factor for peptic ulceration and distal gastric cancer; however, gastritis has no adverse consequences for most hosts, and the prevalence of h. pylori is inversely related to gastroesophageal reflux disease (gerd) and its sequelae, which include ... | 2004 | 14723839 |
| cell adhesion-related gene expression by helicobacter pylori in gastric epithelial ags cells. | helicobacter pylori (h. pylori) infection leads to gastroduodenal inflammation, peptic ulceration and gastric carcinoma. h. pylori may induce disease-specific gene expression in gastric epithelial cells. cdna microarray for 352 cancer-related genes was used to identify the genes altered by h. pylori (caga positive) in gastric epithelial ags cells. expressions of the genes identified on the microarray and other genes closely associated with these genes were determined by reverse transcriptase-pol ... | 2003 | 12757765 |
| il-1 rn 2/2 genotype and simultaneous carriage of genotypes il-1 rn 2/2 and il-1beta-511 t/t associated with oesophagitis in helicobacter pylori-negative patients. | interleukin-1 receptor antagonist genotype 2/2 is associated with a prolonged and enhanced inflammatory response. it is suspected of being a risk factor for atrophic gastritis and gastric cancer and for some autoimmune diseases. no specific genetic risk factors for oesophagitis have been identified so far and there are no reports of il-1 polymorphism in relation to oesophageal disease. | 2003 | 14750640 |
| extracts of spice and food plants from thai traditional medicine inhibit the growth of the human carcinogen helicobacter pylori. | helicobacter pylori (hp) is a gramnegative bacterium and well recognized as being the primary etiological agent responsible for the development of gastritis, dyspepsia, peptic ulcer disease and gastric cancer. in developing countries, a high prevalence of hp infection is associated with an increased incidence of gastric cancer. thailand, however, while having a high prevalence of hp infections, has a lower than expected gastric cancer rate than other developing countries. it has been suggested t ... | 2003 | 14758718 |
| cardiac heart disease in the era of sucrose polyester, helicobacter pylori and chlamydia pneumoniae. | recent evidence associates inflammatory mediators with coronary heart disease. elevation of acute-phase reaction (apr) proteins such as serum amyloid a, fibrinogen, crp and haptoglobin in response to helicobacter pylori (h. pylori) infection was shown to initiate gastritis and ischemic heart disease. positive chlamydia pneumoniae (c. pneumoniae) serology is associated with increased levels of inflammatory cytokines and tumor necrosis factor-alpha (tnf-alpha), which stimulates endothelial cell ac ... | 2004 | 14962637 |
| expression of nuclear factor-kappa b and target genes in gastric precancerous lesions and adenocarcinoma: association with helicobactor pylori caga (+) infection. | to examine the expression of nuclear factor kappab (nf-kappab) and its target genes in intestinal metaplasia (im), dysplasia (dys) and gastric carcinoma (gc) infected with helicobacter pylori (h pylori) and to investigate the mechanism underlying h pylori cytotoxin associated gene a (cag a) infection leading to gastric adenocarcinoma. | 2004 | 14966904 |
| identification of novel virulence-associated genes via genome analysis of hypothetical genes. | the sequencing of bacterial genomes has opened new perspectives for identification of targets for treatment of infectious diseases. we have identified a set of novel virulence-associated genes (vag genes) by comparing the genome sequences of six human pathogens that are known to cause persistent or chronic infections in humans: yersinia pestis, neisseria gonorrhoeae, helicobacter pylori, borrelia burgdorferi, streptococcus pneumoniae, and treponema pallidum. this comparison was limited to genes ... | 2004 | 14977936 |
| [are cox-2 inhibitors truly able to prevent nsaids-associated ulcer?]. | non-steroidal anti-inflammatory drugs(nsaids) have a potential to cause mucosal injury in the gastrointestinal tract. inhibitions of cyclooxygenase, one of the targets of nsaids and direct cytotoxic effects of nsaids, are reported to be involved in nsaids-related mucosal damage. it is estimated that 15-30% of patients taking nsaids develop gastroduodenal ulcers, 2% of patients have life-threatening complications. normal gastroduodenal mucosa expresses only cox-1, and it is reported that nsaids a ... | 2004 | 15038104 |
| helicobacter pylori-mediated gastritis induces local downregulation of secretory leukocyte protease inhibitor in the antrum. | helicobacter pylori-infected subjects exhibited a strong decline in antral secretory leukocyte protease inhibitor (slpi) levels compared to h. pylori-negative subjects and subjects from whom h. pylori had been eradicated (p = 0.002). this reduction was specific for the antrum, whereas slpi expression in corpus and duodenum was not affected. antral slpi levels were inversely correlated with inflammatory scores of antrum-predominant gastritis. | 2004 | 15039364 |
| the future of gastric cancer prevention. | despite advances in surgical treatment and chemotherapy, gastric cancer remains a major global health burden. the most recent estimates show that it is the fourth most common cancer and the second most common cause of cancer deaths worldwide. various etiologic factors have been linked with the disease. it is widely accepted that helicobacter pylori infection and high salt intake are positively associated with this neoplastic process. controversial associations have been found with smoking or dri ... | 2004 | 15052434 |
| genetic pathways of two types of gastric cancer. | multiple genetic and epigenetic alterations in oncogenes, tumour-suppressor genes, cell-cycle regulators, cell adhesion molecules, dna repair genes and genetic instability as well as telomerase activation are implicated in the multistep process of human stomach carcinogenesis. however, particular combinations of these alterations differ in the two histological types of gastric cancer, indicating that well-differentiated or intestinal-type and poorly differentiated or diffuse-type carcinomas have ... | 2004 | 15055305 |
| membrane channel structure of helicobacter pylori vacuolating toxin: role of multiple gxxxg motifs in cylindrical channels. | helicobacter pylori is a human pathogen responsible for severe gastric diseases such as peptic ulcers, gastric adenocarcinoma, and gastric lymphoma. vacuolating toxin (vaca) is crucial in facilitating the colonization of the gastric lining by inducing cell apoptosis and immune suppression. vaca inserts into membranes and forms a hexameric, anion-selective pore. here we present a structural model of the vaca pore that strongly resembles the structure of an unrelated anion-selective channel, mscs. ... | 2004 | 15067113 |
| determinants of helicobacter pylori seroprevalence in mexican adolescents. | helicobacter pylori infection is one of the most common human infections and is considered to play an etiologic role in several gastroduodenal diseases. in this study we determined the h. pylori seroprevalence among adolescents in morelos, mexico, and explored the association between seroprevalence and socioeconomic, dietary and lifestyle variables. | 2004 | 15068411 |
| rapid combined characterization of microorganism and host genotypes using a single technology. | genetic information is becoming increasingly important in diagnosis and prognosis of infectious diseases. in this study we investigated the possibility of using a single technology, the pyrosequencing trade mark technology (biotage ab, uppsala, sweden), to gather several kinds of important genetic information from the human pathogen helicobacter pylori, as well as from the carrier of the h. pylori infection. | 2004 | 15068415 |
| helicobacter pylori infection negatively influences pregnancy outcome in a mouse model. | helicobacter pylori infects the human stomach, causing gastritis, peptic ulcer, and gastric cancer. h. pylori infection has also been related to extra-gastric disorders. we investigated whether h. pylori infection can influence pregnancy in a murine model. | 2004 | 15068417 |
| presence of human mycoplasma dna in gastric tissue samples from korean chronic gastritis patients. | we aimed to determine whether mycoplasmas are present in korean chronic gastritis, and to understand their roles in gastric cancer tumorigenesis, because mycoplasmas resemble helicobacter pylori in terms of ammonia production and induction of inflammatory cytokines in immune and non-immune cells. the presence and identity of mycoplasmas were assessed by semi-nested pcr and sequencing, and the results were compared with pathologic data. fifty-six samples collected from korean chronic gastritis pa ... | 2004 | 15072588 |
| human leukocyte antigen class ii genes and helicobacter pylori infection: does genotype overwhelm environmental exposure? | we investigated associations between human leukocyte antigen class ii genes, environmental exposures, and helicobacter pylori infection. | 2003 | 12921878 |
| evidence for the active role of a novel nuclease from helicobacter pylori in the horizontal transfer of genetic information. | helicobacter pylori is a gram-negative bacterium that colonizes the human stomach, causes gastritis, and is associated with ulcers and gastric cancer. h. pylori is naturally competent for transformation. natural genetic transformation is believed to be essential for the genetic plasticity observed in this species. while the relevance of horizontal gene transfer in h. pylori adaptiveness and antibiotic resistance is well documented, the dna transformation machinery components are barely known. no ... | 2004 | 15090498 |
| detection of helicobacter species dna by quantitative pcr in the gastrointestinal tract of healthy individuals and of patients with inflammatory bowel disease. | in many animal species different intestinal helicobacter species have been described and a few species are associated with intestinal infection. in humans, the only member of the helicobacter family which is well described in literature is helicobacter pylori. no other helicobacter-associated diseases have definitely been shown in humans. we developed a sensitive quantitative pcr to investigate whether helicobacter species dna can be detected in the human gastrointestinal tract. we tested gastri ... | 2004 | 15094170 |
| expression of heat shock protein 32 (hemoxygenase-1) in the normal and inflamed human stomach and colon: an immunohistochemical study. | heat shock protein 32 (hsp32, hemoxygenase-1) is induced by reactive oxygen metabolites (rom) and degrades heme leading to the formation of antioxidant bilirubin. increased mucosal generation of rom occurs in gastritis and inflammatory bowel disease. we aimed to assess mucosal expression of hsp32 in normal stomach and colon and to test the hypothesis that disease-related differential expression occurs in inflamed tissue. gastric body and antral mucosal biopsies were obtained from 33 patients com ... | 2003 | 15115285 |
| differential roles of interleukin-1beta and interleukin-8 in neutrophil transendothelial migration in patients with helicobacter pylori infection. | little information is currently available on the contribution of locally generated inflammatory and chemotactic cytokines to endothelial cell activation and subsequent neutrophil transendothelial migration in patients with helicobacter pylori (h. pylori)-associated gastritis. | 2004 | 15125462 |
| inhibition of primary human t cell proliferation by helicobacter pylori vacuolating toxin (vaca) is independent of vaca effects on il-2 secretion. | recent evidence indicates that the secreted helicobacter pylori vacuolating toxin (vaca) inhibits the activation of t cells. vaca blocks il-2 secretion in transformed t cell lines by suppressing the activation of nuclear factor of activated t cells (nfat). in this study, we investigated the effects of vaca on primary human cd4(+) t cells. vaca inhibited the proliferation of primary human t cells activated through the t cell receptor (tcr) and cd28. vaca-treated jurkat t cells secreted markedly d ... | 2004 | 15128946 |
| helicobacter pylori associated antigastric autoantibodies: role in sjögren's syndrome gastritis. | previous studies have shown that helicobacter pylori seroprevalence in sjögren's syndrome is comparable with that of the general population. however, the origin of the chronic gastropathy associated with this syndrome and the role of local autoimmunity--possibly triggered by bacterial infection--in its pathogenesis remain unclear. | 2004 | 15156903 |
| revisiting the pestilence of helicobacter pylori: insights into geographical genomics and pathogen evolution. | helicobacter pylori causes chronic gastritis and plays important roles in peptic ulcer disease, gastric carcinoma, and mucosa-associated lymphoid tissue (malt) lymphoma. it is believed that h. pylori infects over 50% of the worlds' population. however, only a small subset of infected people experience h. pylori-associated illnesses. associations with disease-specific factors remain enigmatic. the contribution of comparative genomics to our understanding of the genome organisation and diversity o ... | 2004 | 15157625 |
| infiltration of cd8+ t cells containing rantes/ccl5+ cytoplasmic granules in actively inflammatory lesions of human chronic gastritis. | chronic gastritis is frequently associated with infection of helicobacter pylori and characterized by tissue infiltration of neutrophils, lymphocytes, and plasma cells. to address the mechanism of lymphocyte infiltration in chronic gastritis, we examined the expression of chemokines and their receptors using frozen sections of chronic gastritis, obtained from 23 patients who underwent gastrectomy for gastric cancer. by immunohistochemistry, lymphocytes in inflamed gastric mucosa expressed ccr5 a ... | 2004 | 14704722 |
| cathepsins k, l, b, x and w are differentially expressed in normal and chronically inflamed gastric mucosa. | the expression of cathepsins k, l, b, x and w was studied by quantitative rt-pcr in normal and inflamed gastric mucosa (antrum, corpus, cardia). cathepsins b, l, k and x were expressed ubiquitously. in contrast, cathepsin w was expressed at very low levels. infection by helicobacter pylori caused a significant induction of cathepsin x (p<0.008), whereas the other cathepsins were not or only locally affected by h. pylori infection or reflux disease. immunohistochemistry revealed specific expressi ... | 2004 | 15196006 |
| a confirmatory report for the close interaction of helicobacter pylori with gastric epithelial muc5ac expression. | helicobacter pylori (h. pylori) infection is associated with the development of gastritis and peptic ulcer and is presumed to be a risk factor for low-grade b-cell lymphoma and gastric cancer. h. pylori also causes critical alterations in gastric mucin structure. our aim was to determine the effect of h. pylori on muc1, muc2, and muc5ac expression. | 2004 | 15220684 |
| regression of gastric malt-lymphoma under specific therapy may be predict by endoscopic ultrasound. | mucosa-associated lymphoid tissue (malt) lymphomas represent a relatively new described class of rare lymphomas, characterized by an indolent course and favourable outcome with specific therapy. gastric malt lymphomas are associated with chronic helicobacter pylori (hp) infection. we report the case of a 67 year old man admitted for an 8-month history of epigastric pain, anorexia and progressive weight loss. he was diagnosed with low-grade primary gastric malt lymphoma by endoscopy, histopatholo ... | 2004 | 15229778 |
| gastric autoimmunity: the role of helicobacter pylori and molecular mimicry. | pathogens can induce autoreactive t cells to initiate autoimmune disease by several mechanisms. pathogen-induced inflammation results in the enhanced presentation of self antigens, which causes the expansion of the activated autoreactive t cells that are required for disease onset. alternatively, a pathogen might express antigens with epitopes that are structurally similar to epitopes of autoantigens, resulting in a mechanism of molecular mimicry. this is the case for helicobacter pylori-associa ... | 2004 | 15242679 |
| use of a novel enzyme immunoassay based on detection of circulating antigen in serum for diagnosis of helicobacter pylori infection. | recently, noninvasive diagnostic tests for helicobacter pylori infection have gained in significance. we have developed a sensitive and specific noninvasive immunoassay based on the detection of an h. pylori circulating antigen (hpca) in sera from h. pylori-infected individuals. monospecific antibody and western blot analyses were used to demonstrate the presence of the target antigen in h. pylori cell lysate and serum samples. a novel enzyme-linked immunosorbent assay (elisa) was developed for ... | 2004 | 15242956 |
| inhibition of helicobacter pylori adhesion to human gastric adenocarcinoma epithelial cells by acidic polysaccharides from artemisia capillaris and panax ginseng. | helicobacter pylori specifically adheres to host cells, mainly based on carbohydrate-mediated cell-cell interactions. previously, we investigated the anti-adhesive effect of polysaccharide fractions from artemisia capillaris and panax ginseng, using hemagglutination and enzyme-linked glycosorbent assays. in the present study, each active polysaccharide fraction was further purified, resulting in a single peak (fraction f2) using gel filtration fplc, in which no protein content was detectable. us ... | 2004 | 15254854 |
| increased oxidative dna damage, inducible nitric oxide synthase, nuclear factor kappab expression and enhanced antiapoptosis-related proteins in helicobacter pylori-infected non-cardiac gastric adenocarcinoma. | several epidemiological studies have demonstrated a close association between helicobacter pylori (h pylori) infection and non-cardiac carcinoma of the stomach. h pylori infection induces active inflammation with neutrophilic infiltrations as well as production of oxygen free radicals that can cause dna damage. the dna damage induced by oxygen free radicals could have very harmful consequences, leading to gene modifications that are potentially mutagenic and/or carcinogenic. the aims of the pres ... | 2004 | 15259072 |
| induction of maturation and cytokine release of human dendritic cells by helicobacter pylori. | helicobacter pylori causes a persistent infection in the human stomach, which can result in chronic gastritis and peptic ulcer disease. despite an intensive proinflammatory response, the immune system is not able to clear the organism. however, the immune escape mechanisms of this common bacterium are not well understood. we investigated the interaction between h. pylori and human dendritic cells. dendritic cells (dcs) are potent antigen-presenting cells and important mediators between the innat ... | 2004 | 15271898 |
| chemotactic response of helicobacter pylori to human plasma and bile. | to clarify further the role of chemotaxis in helicobacter pylori colonization, the in vitro bacterium response to human plasma and bile (secretions containing chemoeffector compounds that are present in the gastric mucus layer) was examined. human plasma, after dilution to 1 % (v/v) with buffer, was found to be a chemoattractant for the motile bacillus. human gall-bladder bile, after dilution to 2 % (v/v) with buffer, was found to be a chemorepellent, but did not cause the motility of the bacill ... | 2004 | 15272070 |
| helicobacter pylori in children and adolescents. | there is now considerable evidence that suggests that the h. pylori organism isa human pathogen. the strong association between h. pylori and gastroduodenal disease is well documented. a number of hypotheses have been suggested for the pathogenic mechanisms of h. pylori-induced gastroduodenal disease, including the presence of bacterial virulence factors, the production of inflammatory mediators, disregulation of acid secretion, and the host immune response. at the present time, treatment with a ... | 2004 | 15272256 |
| functional adaptation of baba, the h. pylori abo blood group antigen binding adhesin. | adherence by helicobacter pylori increases the risk of gastric disease. here, we report that more than 95% of strains that bind fucosylated blood group antigen bind a, b, and o antigens (generalists), whereas 60% of adherent south american amerindian strains bind blood group o antigens best (specialists). this specialization coincides with the unique predominance of blood group o in these amerindians. strains differed about 1500-fold in binding affinities, and diversifying selection was evident ... | 2004 | 15273394 |
| herpes simplex virus 1 induced lox-1 expression in an endothelial cell line, ecv 304. | infections, such as by chlamydophilia pneumoniae, cytomegalovirus, herpes simplex virus, and helicobacter pylori, have been shown to be involved in atherogenesis. herpes simplex virus i (hsv-1) could infect vascular endothelial cells, and it has been shown that, when endothelial cells were activated with oxidized ldl (oxldl), a number of cellular events are occurred, leading to endothelial cell dysfunction. since lox-1 is a major receptor for oxldl on endothelial cells and its expression was inc ... | 2004 | 15279708 |
| diagnosis of helicobacter pylori infection in dyspeptic patients by stool antigen detection usefulness of a new monoclonal enzyme immunoassay test. | helicobacter pylori antigens can be measured in human stools with an enzyme immunoassay, which may prove to be a valuable non-invasive diagnostic tool. aim. to evaluate the usefulness of a new monoclonal enzyme immunoassay for detecting h. pylori antigens in dyspeptic patients' faeces (femtolab h. pylori, connex, martinsried, germany). | 2004 | 15285523 |
| transcription profile of helicobacter pylori in the human stomach reflects its physiology in vivo. | little is known about levels of expression of helicobacter pylori genes in the human host. we therefore developed a quantitative real-time reverse-transcriptase polymerase chain reaction (qrt-pcr) assay to measure transcript profiles of h. pylori in the human stomach. | 2004 | 15295700 |
| development of two pcr-based techniques for detecting helical and coccoid forms of helicobacter pylori. | the primary mode of transmission of helicobacter pylori, a human pathogen carried by more than half the population worldwide, is still unresolved. some epidemiological data suggest water as a possible transmission route. h. pylori in the environment transforms into a nonculturable, coccoid form, which frequently results in the failure to detect this bacterium in environmental samples by conventional culture techniques. to overcome limitations associated with culturing, molecular approaches based ... | 2004 | 15297506 |
| human polymeric iga is superior to igg and single-chain fv of the same monoclonal specificity to inhibit urease activity associated with helicobacter pylori. | helicobacter-induced gastritis is considered nowadays an epidemic, the prevalence of which is one of the highest world-wide (70%), with as much as 40% of the population in industrialized countries. helicobacter pylori (h. pylori) antigens (ag) capable to elicit a protective immune response in animal models have been identified, but these antigens have not been shown to be strongly immunogenic when administered to humans. due to their stability in the gastric environment and avidity, passive admi ... | 2004 | 15302163 |
| gastric epithelial cell cxc chemokine secretion following helicobacter pylori infection in vitro. | helicobacter pylori infection of the stomach is commonly associated with infiltration of neutrophils. gastric epithelial cells are recognized as central mediators of tissue responses to this organism. the aim of the present study was to ascertain patterns of production of three neutrophil chemoattractant chemokines following infection of gastric epithelial cells with h. pylori in vitro. | 2004 | 15304113 |
| experimental helicobacter pylori infection in humans: a multifaceted challenge. | | 2004 | 15306572 |
| challenge model for helicobacter pylori infection in human volunteers. | a reliable challenge model is needed to evaluate helicobacter pylori vaccine candidates. | 2004 | 15306577 |
| is the host responsible? -- the role of the immune system in helicobacter pylori infection. | helicobacter pylori is the primary aetiological agent of chronic gastritis and a necessary factor in most peptic ulcer disease. to date the majority of studies, which have examined factors predictive of disease outcome, have concentrated on bacterial virulence factors. recent evidence suggests that the immune response might be responsible. fc receptors polymorphisms have been implicated in autoimmune diseases and persistent bacterial infections. individuals who are h. pylori positive and homozyg ... | 2004 | 14729011 |
| predicting protein-protein interactions using signature products. | proteome-wide prediction of protein-protein interaction is a difficult and important problem in biology. although there have been recent advances in both experimental and computational methods for predicting protein-protein interactions, we are only beginning to see a confluence of these techniques. in this paper, we describe a very general, high-throughput method for predicting protein-protein interactions. our method combines a sequence-based description of proteins with experimental informati ... | 2005 | 15319262 |
| extracellular signal-regulated protein kinase mediates interleukin 17 (il-17)-induced il-8 secretion in helicobacter pylori-infected human gastric epithelial cells. | helicobacter pylori-induced mucosal inflammation results in high production of interleukin 17 (il-17), a potent inducer of il-8 in gastric epithelial cells. the aim of this study was to investigate signaling pathways by which il-17 regulates il-8 production in human gastric epithelial cells. activation of mitogen-activated protein (map) kinases in both il-17-stimulated mkn28 cells and epithelial cells isolated from h. pylori-colonized gastric mucosa was assessed by western blotting. in il-17-sti ... | 2004 | 15321994 |
| differential expression of bax and bcl-2 in gastric mucosa. | | 2004 | 15326840 |
| one patient, two lymphomas. simultaneous primary gastric marginal zone lymphoma and primary duodenal follicular lymphoma. | we report the case of a 73-year-old man who presented with a 2- to 3-month history of epigastric discomfort and guaiac-positive stool. an upper gastrointestinal endoscopy revealed a diffuse erythematous nodular mucosa and submucosal thickening in the stomach. diffuse mucosal nodularity was also found in the second portion of the duodenum. a complete workup with histologic, immunohistochemical, and molecular studies revealed 2 distinct, apparently unrelated lymphomas, namely, a gastric marginal z ... | 2004 | 15335250 |
| [construction, expression and antigenicity of bivalent vaccine candidate of human helicobacter pylori]. | to construct a recombinant vector containing fused gene of heat shock protein a(hspa) and outer membrane protein(omp) with m(r) 18,000, from human helicobacter pylori(hp) and express the fusion protein in e.coli bl21. | 2004 | 15182624 |
| [pathogenesis and treatment of refractory gastroesophageal reflux disease in japanese patients]. | prevalence of refractory gastroesophageal reflux disease (gerd) defined as a patient who have persistent gerd symptoms during treatment with proton pump inhibitor (ppi) is rare in japanese patinets. pathogenesis of refractory gerd is associated with several factors including dysfunction of esophageal motility, presence of severe hiatal hernia, complication such as stricture and short esophagus, extensive metabolizer of cyp2c19 genotype, nocturnal gastric acid breakthrough, absence of h. pylori i ... | 2004 | 15344542 |
| effect of h. pylori on the expression of trail, fasl and their receptor subtypes in human gastric epithelial cells and their role in apoptosis. | in the human stomach expression of tnf-related apoptosis inducing ligand (trail) and its receptors and the modulatory role of helicobacter pylori are not well described. therefore, we investigated the effect of h. pylori on the expression of trail, fasl and their receptors (trail-r1-r4, fas) in gastric epithelial cells and examined their role in apoptosis. | 2004 | 15361075 |
| geranylgeranylacetone attenuates suppression by helicobacter pylori extract of human umbilical vein epithelial cell growth. | helicobacter pylori infection delays gastric ulcer healing. angiogenesis is important for the healing of gastric ulcers. therefore, the effects of h. pylori water extract and a novel antiulcer drug, geranylgeranylacetone, on the viability of human umbilical vein epithelial cells (huvecs) were investigated. | 2004 | 15362801 |
| helicobacter pylori infection in pediatric population: epidemiology, pathophysiology, and therapy. | helicobacter pylori, one of the most commonly encountered human pathogens, has been recognized in more than half of adults and children with chronic nonspecific gastritis, and nearly all children with peptic ulcer disease demonstrate antral infection with h. pylori. a high prevalence and early colonization of h. pylori infection in childhood was described in developing countries in contrast to developed countries. the current diagnostic methods include histology, microbiological culture, urease ... | 2004 | 15371120 |
| influence of gastritis on cyclooxygenase-2 expression before and after eradication of helicobacter pylori infection. | helicobacter pylori infection causes chronic gastritis and induces cyclooxygenase (cox)-2 expression. the relationship between gastritis and cox-2 expression is not well understood, especially long after the organism has been eradicated. we designed a study to elucidate this relationship. | 2004 | 15371919 |
| cyp2c19 polymorphism is a major predictor of treatment failure in white patients by use of lansoprazole-based quadruple therapy for eradication of helicobacter pylori. | proton pump inhibitors, metabolized by the polymorphic enzyme cytochrome p450 (cyp) 2c19, are essential drugs for helicobacter pylori eradication. it was reported that patients with cyp2c19 wild type in asia had lower eradication rates. this study tests the hypothesis that cyp2c19 wild type ( wt/wt ) in white patients is also associated with a higher probability of treatment failure. | 2004 | 15371981 |
| essential domain of receptor tyrosine phosphatase beta (rptpbeta) for interaction with helicobacter pylori vacuolating cytotoxin. | helicobacter pylori produces a potent exotoxin, vaca, which causes progressive vacuolation as well as gastric injury. although vaca was able to interact with two receptor-like protein tyrosine phosphatases, rptpbeta and rptpalpha, rptpbeta was found to be responsible for gastric damage caused by vaca. to define the region of rptpbeta involved in vaca binding, we made mutants of human cdna rptpbeta-b, a short receptor form of rptpbeta. immunoprecipitation experiments to assess vaca binding to rpt ... | 2004 | 15383529 |
| sensitivity of helicobacter pylori to an innate defence mechanism, the lactoperoxidase system, in buffer and in human whole saliva. | helicobacter pylori has frequently been isolated from human dental plaque, and oral spread via saliva is thought to be one of its principal modes of transmission. among other innate defence systems human saliva contains peroxidase enzymes and lysozyme. the sensitivity of h. pylori to physiological concentrations of lactoperoxidase and its salivary substrate thiocyanate, and different amounts of hydrogen peroxide (h(2)o(2)) was investigated in buffer and in human whole saliva. the effect of lysoz ... | 2004 | 15314191 |
| mucosal concentration of basic fibroblast growth factor in the healing process in human giant gastric ulcers. | basic fibroblast growth factor (bfgf) is a key factor in the healing of human and experimental peptic ulcers, but the behavior of bfgf in human giant gastric ulcer remains to be determined. we determined the bfgf content in the rim of giant ulcers (bfgf rim) and in non-ulcerated mucosa located opposite the ulcer (bfgf opposite) before and during treatment. | 2004 | 15086596 |
| elevated concentrations of alpha-defensins in gastric juice of patients with helicobacter pylori infection. | defensins (alpha- and beta-defensins) are endogenous antimicrobial peptides. little is known about alpha-defensins during helicobacter pylori infection. | 2004 | 15447750 |
| solving the riddle of codon usage preferences: a test for translational selection. | translational selection is responsible for the unequal usage of synonymous codons in protein coding genes in a wide variety of organisms. it is one of the most subtle and pervasive forces of molecular evolution, yet, establishing the underlying causes for its idiosyncratic behaviour across living kingdoms has proven elusive to researchers over the past 20 years. in this study, a statistical model for measuring translational selection in any given genome is developed, and the test is applied to 1 ... | 2004 | 15448185 |
| helicobacter pylori infection causes persistent platelet activation in vivo through enhanced lipid peroxidation. | we aimed at investigating the relationship between helicobacter pylori infection and in vivo lipid peroxidation and platelet activation, as reflected by urinary 8-iso-prostaglandin (pg)f(2alpha) and 11-dehydro-thromboxane (tx)b2, respectively, in otherwise healthy dyspeptic subjects. | 2005 | 15472127 |
| epidemiology of non-hodgkin's lymphoma (nhl): trends, geographic distribution, and etiology. | while for most cancers incidence and mortality are decreasing, those of non-hodgkin's lymphoma (nhl) are steadily increasing. research to define reasons for this increase is extensive, but has not yet resolved them. we have conducted a literature analysis on trends regarding changes in the incidence, geographic distribution, and etiologic factors of nhl. from our own and previous analyses, an increasing nhl incidence at a rate of 3-4% per year was observed for the 1970s and 1980s. this stabilize ... | 2005 | 15480663 |
| specific immunoglobulin a antibodies in maternal milk and delayed helicobacter pylori colonization in gambian infants. | immunoglobulin a (iga) in maternal milk may protect gambian infants from early helicobacter pylori colonization. this study sought evidence that this protection could be due to specific iga antibodies. | 2004 | 15486839 |
| nod1 responds to peptidoglycan delivered by the helicobacter pylori cag pathogenicity island. | epithelial cells can respond to conserved bacterial products that are internalized after either bacterial invasion or liposome treatment of cells. we report here that the noninvasive gram-negative pathogen helicobacter pylori was recognized by epithelial cells via nod1, an intracellular pathogen-recognition molecule with specificity for gram-negative peptidoglycan. nod1 detection of h. pylori depended on the delivery of peptidoglycan to host cells by a bacterial type iv secretion system, encoded ... | 2004 | 15489856 |
| [genetic susceptibility and risk of gastric cancer in a human population of cauca, colombia]. | gastric cancer (gc) is the main cause of mortality by cancer in colombia. glutathione s-transferase (gst) enzymes are involved in the detoxification of many environmental carcinogens. the homozygous deletions of glutathione s-transferase m1 (gstm1-0) and glutathione s-transferase t1 (gstt1-0) have been associated with several types of cancer. the risk to develop gc has been associated with environmental factors and helicobacter pylori infection. the tumor necrosis factor (tnf-alpha) and its leve ... | 2004 | 15495595 |
| review article: relationship between the metabolism and efficacy of proton pump inhibitors--focus on rabeprazole. | proton pump inhibitors are now considered the mainstay of treatment for acid-related disease. although all proton pump inhibitors are highly effective, the antisecretory effects of different drugs in this class are not completely consistent across patients. one reason for this is the acid-suppressing effect of helicobacter pylori infection, which may augment the actions of proton pump inhibitors. a second important reason for interpatient variability of the effects of proton pump inhibitors on a ... | 2004 | 15496214 |
| pathogen burden, inflammation, proliferation and apoptosis in human in-stent restenosis. tissue characteristics compared to primary atherosclerosis. | pathogenic events leading to in-stent restenosis (isr) are still incompletely understood. among others, inflammation, immune reactions, deregulated cell death and growth have been suggested. therefore, atherectomy probes from 21 patients with symptomatic isr were analyzed by immunohistochemistry for pathogen burden and compared to primary target lesions from 20 stable angina patients. while cytomegalovirus, herpes simplex virus, epstein-barr virus and helicobacter pylori were not found in isr, a ... | 2004 | 15528935 |
| [probiotics: from metchnikoff to the current preventive and therapeutic possibilities]. | about a century ago, metchnikoff first hypothesised that some intestinal bacteria "produce compounds useful against a premature ageing". since then, studies progressed over last century, leading to a remarkable improvement of the knowledge about the role of intestinal micro-organisms. nowadays a number of different micro-organisms satisfying certain requisites are named probiotics and are produced on a large scale. at present, a rational use of probiotics with preventive and therapeutic purposes ... | 2004 | 15529809 |
| microsomal prostaglandin e synthase (mpges)-1, mpges-2 and cytosolic pges expression in human gastritis and gastric ulcer tissue. | recently, three different prostaglandin e2 synthases have been identified: microsomal prostaglandin e synthase (mpges)-1, cytosolic pges (cpges), and mpges-2; however, their role and connection to cyclooxygenase (cox)-2 in the gastric ulcer repair process remain unknown. therefore, we examined mpges-1, cpges, and mpges-2 expression and localization in the stomach in vitro and in vivo. tissues were obtained from helicobacter pylori (h. pylori)-infected patients and consisted of surgical resection ... | 2005 | 15531909 |
| downregulation of cxcr1 and cxcr2 expression on human neutrophils by helicobacter pylori: a new pathomechanism in h. pylori infection? | in helicobacter pylori gastritis, neutrophil activation and migration, which play central roles in the pathogenesis of the disease, are regulated by the neutrophil attractant chemokines interleukin 8 (il-8) and groalpha, whose secretion is induced by h. pylori. however, the modulation of the corresponding chemokine receptors cxcr1 and cxcr2 on human neutrophils under the influence of h. pylori has not been investigated. incubation of neutrophils with cag(+) and cag deletion h. pylori strains res ... | 2004 | 15557597 |
| role of the receptor-mediated apoptosis in helicobacter pylori in gastric epithelial cells. | two major pathways leading to apoptosis have been described. it has been shown that helicobacter pylori-mediated apoptosis is mainly effected through the mitochondrial pathway (type ii). the role of the type i pathway, including the death receptors, has been discussed controversially. therefore, we investigated the role of fas ligand (fasl) and trail in h. pylori-mediated apoptosis by overexpressing antiapoptotic proteins in the human gastric epithelial cell line ags. | 2004 | 15557763 |
| the adherent gastric mucous layer is composed of alternating layers of muc5ac and muc6 mucin proteins. | mucin-type glycoproteins are the major structural proteins in gastric mucus. stomach mucin proteins include muc5ac, synthesized by surface foveolar or pit cells, and muc6, synthesized by neck and gland cells. the aim of this study was to determine the spatial distribution of these mucin proteins within the extracellular mucous coat. double-labeling immunoflourescence/confocal microscopy was used in histologically normal surgical resection specimens. intralumenal mucin within antral glands consis ... | 2004 | 15573912 |
| spermine oxidation induced by helicobacter pylori results in apoptosis and dna damage: implications for gastric carcinogenesis. | oxidative stress is linked to carcinogenesis due to its ability to damage dna. the human gastric pathogen helicobacter pylori exerts much of its pathogenicity by inducing apoptosis and dna damage in host gastric epithelial cells. polyamines are abundant in epithelial cells, and when oxidized by the inducible spermine oxidase smo(paoh1) h(2)o(2) is generated. here, we report that h. pylori up-regulates mrna expression, promoter activity, and enzyme activity of smo(paoh1) in human gastric epitheli ... | 2004 | 15574757 |
| helicobacter-induced intestinal metaplasia in the stomach correlates with elk-1 and serum response factor induction of villin. | chronic helicobacter pylori infection results in serious sequelae, including atrophy, intestinal metaplasia, and gastric cancer. intestinal metaplasia in the stomach is defined by the presence of intestine-like cells expressing enterocyte-specific markers, such as villin. in this study, we demonstrate that villin is expressed in intestine-like cells that develop after chronic infection with h. pylori in both human stomach and in a mouse model. transfection studies were used to identify specific ... | 2004 | 15576363 |
| gastric malt lymphomas are divided into three groups based on responsiveness to helicobacter pylori eradication and detection of api2-malt1 fusion. | gastric malt lymphoma shows unique features including regression by helicobacter pylori eradication and api2-malt1 fusion. we performed a molecular and clinicopathologic study for 115 cases. all eradication-responsive cases were devoid of api2-malt1 fusion. all tumors positive for the fusion and all negative for h. pylori infection were nonresponsive to the eradication. consequently, gastric malt lymphomas were divided into three groups: eradication-responsive and fusion-negative (group a, n = 7 ... | 2004 | 15577674 |
| novel 180- and 480-base-pair insertions in african and african-american strains of helicobacter pylori. | helicobacter pylori is a genetically diverse bacterial species that chronically infects human stomachs and sometimes causes severe gastroduodenal disease. studies of polymorphic dna sequences can suggest geographic origins of individual strains. here, we describe a 180-bp insertion (ins180), which is just after the translation stop of a gene of unknown function, near the promoter of jhp0152-jhp0151 two-component signal transduction genes in strain j99, and absent from this site in strain 26695. ... | 2004 | 15583296 |
| the selective cyclooxygenase-2 inhibitor nimesulide prevents helicobacter pylori-associated gastric cancer development in a mouse model. | helicobacter pylori infection can lead to gastric cancer, and cyclooxygenase-2 (cox-2) is overexpressed in the stomach during h. pylori infection. therefore, we investigated whether nonsteroidal anti-inflammatory drugs might protect against this form of cancer. specifically, we examined the chemopreventive effect of the cox-2 inhibitor nimesulide on h. pylori-associated gastric carcinogenesis in mice. | 2004 | 15585646 |