Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0847097 (acidity)
 15,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Helicobacter pylori is the major causative agent of chronic antral gastritis and is thought to be involved in the pathogenesis of mucosa-associated lymphoid tissue lymphoma (MALToma) developing in the human stomach. The aim of this study was to clarify whether corporal autoimmune gastritis (AIG), which is known to decrease acidity due to destruction of parietal cells, predisposes mice to H. pylori infection, thereby leading to MALToma-like pathology. BALB/c mice in which AIG had been induced by thymectomy 3 days after birth (AIG mice) were used. The AIG mice were orally administered mouse-adapted H. pylori at the age of 6 weeks and were examined histologically and serologically after 2 to 12 months. The results were compared with those obtained from uninfected AIG mice and infected normal mice. Germinal centers were induced in the corpus in 57% of the H. pylori-infected AIG mice, which elicited anti-H. pylori antibody responses in association with upregulation of interleukin-4 (IL-4) mRNA. In these mice, parietal cells remained in the corpus mucosa. These findings were in contrast to those with the uninfected AIG mice: fundic gland atrophy due to disappearance of parietal cells associated with upregulation of gamma interferon, but not IL-4, mRNA and no germinal center formation in the corpus. These observations suggest that AIG alters the infectivity of H. pylori, leading to MALToma-like follicular gastritis, at an early stage after H. pylori infection.
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PMID:Induction of follicular gastritis following postthymectomy autoimmune gastritis in Helicobacter pylori-infected BALB/c mice. 1060 74

Helicobacter pylori (Hp) infection is one of the most common chronic bacterial infections worldwide. The pathogenic properties of Hp are due to its ability to survive in the gastric juice, to escape the gastric acidity and to colonise the crypts of the gastric mucosa. Eradication of Hp is needed for patients with a gastroduodenal ulcer associated with Hp gastritis. Eradication modifies the natural history of the disease and greatly reduces the risk of recidive and the consequences of the discovery of Hp have been spectacular, in particular in duodenal ulcer disease. A tritherapy regimen given for 7 days combining a double-dosed proton pump inhibitor, amoxicillin (2 g/d) and clarithromycin (0.5 g bid) is used. Persistent infection may lead to a progression toward atrophy, intestinal metaplasia, dysplasia and eventually cancer. However, systematic eradication in order to reduce the incidence of gastric adenocarcinoma is not recommended. Acquisition of mucosa-associated lymphoid tissue (malt) lymphoma is related to gastritis induced by Hp infection and is commonly postulated as the initial stage in the development of malt lymphoma. Eradication is also indicated for patients with lymphoma with a low degree of malignancy.
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PMID:[Helicobacter pylori update]. 1497 70

The gut of a healthy adult harbours a myriad of different microbial species. It is estimated that approximately 10 14 are present in total bacterial colony forming units (CFU). Each colony colonizes a specific intestinal tract. In healthy adult, the main control of intestinal bacterial colonization occurs through gastric acidity but also other factors can influence the intestinal microenvironment such as pH, temperature, competition among different bacterial strains, peristalsis, drugs, radiotherapy and much more. Impaired microbial homeostasis leads to an alteration of the permeability of tissue, together with the activation of the intestinal immune system MALT (mucosal associated lymphoid tissue). In this regard we discuss the increasing experimental evidences of the role of commensal microbiota in the activation of specific intestinal immunocompetent cells. The aforementioned micro-environmental changes provide the substrate for the etiopathogenetic outbreak of numerous pathologies of gastro-intestinal tract, such as intestinal chronic inflammation (Crohn's disease and Ulcerative Colitis), together with a miscellany of extra intestinal disorders. This article is an overview of the latest scientific findings about the close causal relationship between intestinal microbial flora and inflammatory bowel diseases or other extra-intestinal diseases; it is also mentioned the possible relationship between mycobacteria and Chron's disease. Finally we analyse the beneficial role of probiotics.
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PMID:From gut microflora imbalance to mycobacteria infection: is there a relationship with chronic intestinal inflammatory diseases? 2198 43

Helicobacter pylori is a Gram-negative bacterium that causes chronic atrophic gastritis and peptic ulcers and it has been associated with the development of gastric adenocarcinoma and mucosa-associated lymphoid tissue (MALT). One of the more remarkable characteristics of H. pylori is its ability to survive in the hostile environment of the stomach. H. pylori regulates the expression of specific sets of genes allowing it to survive high acidity levels and nutrient scarcity. In the present study, we determined the expression of virulence associated protein D (VapD) of H. pylori inside adenocarcinoma gastric (AGS) cells and in gastric biopsies. Using qRT-PCR, VapD expression was quantified in intracellular H. pylori-AGS cell cultures at different time points and in gastric mucosa biopsies from patients suffering from chronic atrophic gastritis, follicular gastritis, peptic ulcers, gastritis precancerous intestinal metaplasia and adenocarcinoma. Our results show that vapD of H. pylori presented high transcription levels inside AGS cells, which increased up to two-fold above basal values across all assays over time. Inside AGS cells, H. pylori acquired a coccoid form that is metabolically active in expressing VapD as a protection mechanism, thereby maintaining its permanence in a viable non-cultivable state. VapD of H. pylori was expressed in all gastric biopsies, however, higher expression levels (p = 0.029) were observed in gastric antrum biopsies from patients with follicular gastritis. The highest VapD expression levels were found in both antrum and corpus gastric biopsies from older patients (>57 years old). We observed that VapD in H. pylori is a protein that is only produced in response to interactions with eukaryotic cells. Our results suggest that VapD contributes to the persistence of H. pylori inside the gastric epithelial cells, protecting the microorganism from the intracellular environment, reducing its growth rate, enabling long-term infection and treatment resistance.
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PMID:High expression of Helicobacter pylori VapD in both the intracellular environment and biopsies from gastric patients with severity. 3216 5