DIRECT CYTOPATHIC EFFECTS OF HELICOBACTER PYLORI ON HUMAN GASTRIC EPITHELIUM

幽门螺杆菌是最常见的病因之一 这种细菌已被确定在80-90%的人胃炎。 成人慢性胃炎患者和90-100%的成人慢性胃炎患者 消化性溃疡最近的研究表明，长期感染 由H.幽门螺杆菌与胃溃疡的风险增加有关， carcinoma.然而，H.幽门导致胃 上皮细胞损伤是未知的，其在发病机制中的作用， 对消化性溃疡的了解更少。感染这种 细菌局限于胃粘膜，食道和 仅在胃上皮异位或化生时累及十二指肠 存在于这些地区。H.幽门螺杆菌感染 胃粘膜在美国非常常见。的50%以上 60岁以上的成年人感染了这种细菌， 非裔美国人的患病率比非裔美国人高出约38%。 所有年龄段的白人。在这项研究中，人类体外培养系统 用于鉴定H.幽门结合在胃上 上皮细胞参与其发病机制。细菌粘附， 至少是一部分，可能是H的原因。幽门螺杆菌的偏好 胃粘膜具体目标是：（1）确定 在感染这种细菌的患者中发现的不同病理学是 继发于分离株之间毒素产生的差异，或 宿主对该细菌的反应差异;（2）鉴定 H.幽门螺杆菌;（3）评估机制， 毒素对离体人胃粘膜细胞的损伤作用。细胞损伤 用光和电子从形态学上评价活力 通过细胞掺入中性红染料， 乳酸脱氢酶释放到培养基中。变化 暴露后与细胞损伤相关的上皮细胞增殖 使用溴脱氧尿苷来测量这种细菌。GCRC 门诊设施将有助于获得血液， 临床评估中的其他身体分泌物。GCRC住院患者 调查的早期阶段不需要设施， 随着数据的产生和主题的出现，购买可能变得更加重要。 需要密切监测和临床评价。

Helicobacter pylori has been implicated as one of the most common causes of gastritis in man. This bacterium has been identified in 80-90% of adult patients with chronic gastritis and 90-100% of adult patients with peptic ulcer disease. Recent studies have shown that long-term infection by H. Pylori is associated with an increased risk of developing gastric carcinoma. However, the mechanism by which H. Pylori causes gastric epithelial cell injury is unknown and its role in the pathogenesis of peptic ulcer disease is even less understood. Infection with this bacterium is localized to the gastric mucosa, with the esophagus and duodenum only involved when heterotopic or metaplastic gastric epithelium is present in these areas. The prevalence of H. pylori infection of the gastric mucosa is very common in the United States. More than 50% of adults over 60 years of age are infected with this bacterium, and the prevalence in African Americans is approximately 38% higher than that of whites in all age groups. In this study, a human in vitro culture system is employed to identify the receptors to which H. Pylori binds on gastric epithelial cells is involved in its pathogenesis. Bacterial adherence, at least is part, may be responsible for H. pylori's predilection for gastric mucosa. Specific goals are to: (1) determine whether the differing pathology found in patients infected with this bacterium is secondary to the differences in toxin production between isolates or differences in host response to this bacterium; (2) identify the cytotoxin(s) produced by H. pylori; and (3) evaluate the mechanism of toxin induced cell injury on human gastric mucosa in vitro. Cell injury and viability is evaluated morphologically with light and electron microscopy and functionally by cell incorporation of neutral red dye and release of lactate dehydrogenase into culture media. Changes in epithelial cell proliferation associated with cell injury after exposure to this bacteria are being measured using bromodeoxyuridine. GCRC outpatient facilities will be useful in the acquisition of blood and other body secretions from clinical evaluations. GCRC inpatient facilities are not necessary for the early stages of this investigation, buy may become more critical as data are generated and subjects are in need of close monitoring and clinical evaluation.