Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0038358 (gastric ulcer)
 5,179 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Helicobacter pylori is the major causative agent of chronic gastritis. It is associated with duodenal and gastric ulcer and with the majority of primary gastric B-cell lymphomas; furthermore, there is a strong epidemiological association with gastric cancer. One intriguing aspect of this infection is the ability of H pylori to persist despite the vast array of host immune responses. This article reviews what is known about the immune responses against H pylori, emphasizing what is generally accepted and applicable while highlighting areas of controversy. The first section delineates the genesis of the inflammatory responses, which initiate with the production of tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-1, IL-6, and IL-8 and continue with the recruitment of neutrophilic polymorphonuclear cells, lymphocytes, plasma cells, macrophages and eosinophils, and later with the development and recruitment of specifically committed cells (lymphocytes sensitized to H pylori antigens and B cells producing immunoglobulin (Ig)A, IgG, and possibly IgE antibodies against a variety of H pylori surface and flagellar proteins as well as bacterial toxins). The second part of the article focuses on the development of lymphoid follicles in the gastric mucosa, a phenomenon that for the first time links an immune response (the recruitment of mucosa-associated lymphoid tissue [MALT] to the gastric mucosa in response to H pylori infection) with the development of a neoplastic growth (the development of gastric MALT lymphomas). The local and systemic antibody responses are discussed in the light of their potential application in the development of diagnostic tests and vaccines. Particular emphasis is placed on the controversies surrounding the significance of antibodies directed against a 120 to 140 kDa protein apparently associated with more "aggressive" (sometimes also called "ulcerogenic" or "pathogenic") strains of H pylori.
 ...
PMID:The immunobiology of Helicobacter pylori gastritis. 900 Apr 97

The discovery of Helicobacter pylori (H. pylori) has revolutionised the pathophysiological and clinical approach to gastric and duodenal ulcer. Since the first paper identifying H. pylori was published only 19-20 years ago, it has been found out that this bacterium causes probably the commonest human infection. Like other revolutions in history, the original directions of the H. pylori story have changed in response to conflicting ideologies, observation, and practices. It is known that once H. pylori is acquired, colonisation continues for life unless the organism is eliminated by antimicrobial treatment or by the usually late-in-life development of the atrophic gastritis. If any recent achievement in the world of medicine is to be called revolutionary, then it is the discovery of the role of this spiral bacterium in the etiopathogenesis of gastritis, gastric ulcer, duodenal ulcer, gastric adenocarcinomas and gastric mucosa-associated lymphoid type (MALT) B-cell lymphomas. Essentially everyone who carries the organism in the gastric mucous layer has evidence of tissue reaction (termed chronic active gastritis), but most colonised persons remain asymptomatic for life. In the absence of treatment, the presence of H. pylori can be determined with a high degree of confidence by endoscopy (with culture, histologic examination, or urease testing of gastric biopsy specimens), by serologic testing, or by urea breath tests. After successful treatment, specific antibody levels decrease so slowly that serologic testing cannot be used to document success for at least 6 months. In most patients, elimination of H. pylori changes the natural history of peptic ulcer disease and of gastric MALT lymphomas. It is now recommended that these patients have to be treated to eliminate H. pylori because the benefits seem to substantially outweigh the risks and costs. Currently, enthusiasts, drug companies, and the lay press are putting pressure on physicians to eliminate H. pylori from all patients, symptomatic or not, in whom it is detected. There is little evidence that this is appropriate, and management will continue to change as new knowledge emerges and socioeconomic environments change in ways that are relevant to H. pylori and clinical medicine.
 ...
PMID:[Is the only good Helicobacter a dead Helicobacter?]. 1205 16

The author reviewed pathologic features of 37 cases of malignant lymphoma in the gastrointestinal organs in the last 10 years in our pathology laboratory. The current WHO classification was adopted. The 37 cases consisted of 20 males and 17 female, and the age ranged from 46 to 89 years with a median of 69 years. Of the 37 cases, 25 cases (68%) were gastric lymphomas, 6 cases (16%) were small intestinal lymphomas, and 6 cases (16%) were colon lymphomas. Of the 37 cases, 35 cases (95%) were B-cell neoplasms and 2 cases (5%) were T-cell neoplasms. In the 25 gastric lymphomas (male:female=14:11, age range 46-84 years, median 70 years) 11 cases were diffuse large B-cell lymphomas, and 14 cases were extranodal marginal zone B-cell lymphomas (MALT lymphomas). The clinical endoscopic diagnosis was gastritis in 3, gastric ulcer in 3, gastric carcinoma in 7, carcinoid in 1, submucosal tumor in 1, malignant lymphoma in 2, and suspected MALT lymphoma in 8. In the 6 small intestinal lymphomas (male:female=2:4, age range 49-89 years, median 70 years), all cases were located in the ileum. Of the 6 cases, 4 were diffuse large B-cell lymphoma and 2 were peripheral T-cell lymphoma. One case showed multiple lymphomas, and one case was associated with rectal adenocarcinoma and one case with gastric MALT lymphoma. The clinical diagnosis was adenocarcinoma in 2, suspected lymphoma in 2, and ileal tumor in 2. In the 6 colon lymphomas (male:female=4:2, age range 69-86 years, median 74 years), 5 cases were diffuse large B-cell lymphomas and one case was follicular lymphoma. Clinical endoscopic diagnosis was GIST in 1, colon carcinoma in 4, and colon polyp in 1. Cases of Hodgkin's disease, mantle cell lymphoma, Burkitt lymphoma were not recognized in the present series. In summary, the author reported pathologic features of 37 cases of gastrointestinal malignant lymphoma in our laboratory in the last 10 years.
 ...
PMID:Gastrointestinal malignant lymphoma: a pathologic study of 37 cases in a single Japanese institution. 2311 30