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41.
目的研究幽门螺杆菌(Hp)根除前后胃黏膜上皮细胞凋亡和端粒酶逆转录酶(hTERT)表达及其与bcl-2、c-myc蛋白表达的关系。方法采用脱氧核糖核酸末端转移酶介导的缺口末端标记(TUNEL)技术及免疫组化染色方法检测39例却Hp性患者根除治疗及21例却阴性患者对症治疗前后胃黏膜上皮细胞凋亡、hTERT、bcl-2、c—myc蛋白表达的变化。结果治疗前却阳性者胃黏膜上皮细胞凋亡指数为16.2%,显著高于却阴性者(P〈0.05);却阳性者hTERT、c—myc蛋白表达显著高于却阴性者(53.8%比23.8%;53.8%比28.6%,P〈0.05)。邯根除者治疗后胃黏膜上皮细胞凋亡、hTERT及bcl-2、c—myc蛋白表达与根除前相比均显著下降(16.9%比9.0%;59.3%比22.2%;59.3%比25.9%;59.3%比14.8%,P〈0.01),且与却阴性对照组相比差异无统计学意义(P〈0.05);而邯未根治组及对照组上述指标均无显著变化。治疗前bcl-2、c—myc蛋白与hTERT呈显著正相关,秩相关系数r分别为0.269、0.474(P〈0.05)。结论却感染诱导细胞凋亡及hTERT过度表达,使胃黏膜不稳定性增加。根除却可纠正细胞凋亡失调,使hTERT表达下降或消失,从而降低胃癌发生的可能性。bcl-2及c—myc蛋白对hTERT表达可能具有调控作用。  相似文献   
42.
目的:了解就诊及体检人群中幽门螺杆菌(HP)感染状况,探讨HP感染与相关疾病的关系。方法:采用金标免疫斑点法对3996人进行血清抗HP-IgG检测,还对其中2259人检测了抗HP-IgM。结果:(1)3996例中血清抗 HP-IgG总阳性率为76.0%;2259例 HP-IgM阳性率为41.2%。(2)HP-IgG、HP-IgM在性别间无显著性差异(P>0.05)。(3)年龄因素对HP-IgG和HP-IgM阳性率有显著(P<0.05)和极显著(P<0.001)影响。(4)HP感染存在家庭聚集倾向。(5)血清HP抗体阳性率升高的疾病:大于28 d小儿,消化系统疾病组较健康对照组,抗HP-IgM阳性率存在显著性差异(P<0.05);在成人中胃肠道疾病组与健康体检组抗HP-IgG阳性率相比,有极显著性差异(P<0.001);肝、胆、胰疾病、循环系统疾病组与健康体检组比较有显著性差异(P<0.05)。结论:HP感染与多种胃肠道、肝胆胰及循环系统疾病有关;人群初次感染始于婴幼儿期,且受家庭因素影响。  相似文献   
43.
Antibiotic-associated haemorrhagic colitis is an uncommon cause of bloody diarrhoea in patients taking penicillin or penicillin-related antibiotics. Symptoms of abdominal pain and bloody diarrhoea occur within 1 week of antibiotic use and resolve without specific therapy within days of discontinuing the offending antibiotic. There is an apparent increased incidence of the disease in patients of Oriental ethnicity. The pathogenesis is unknown. We present two cases of haemorrhagic colitis in patients taking penicillin-related antibiotics who presented within 4 months of each other. One of the patients was being treated for Helicobacter pylori infection. The published literature is reviewed with particular emphasis on the histology and pathogenesis of the condition.  相似文献   
44.
Zusammenfassung Trotz der H?ufigkeit der Erkrankung liegen nur wenige gesicherte Erkenntnisse über die ?tiologie der chronischen Urtikaria vor. Bei 10 Patienten, bei denen keine anderweitige Ursache für die Erkrankung ermittelt werden konnte, führten wir eine Gastroskopie durch. Bei 8 der 10 Patienten konnte eine Besiedlung der Magenschleimhaut mit Helicobacter pylori gesichert werden. Die Urtikaria heilte innerhalb weniger Tage bei allen Patienten ab, nachdem wir eine Therapie mit Amoxicillin und Omeprazol einleiteten. Eingegangen am 6. Februar 1995 Angenommen am 12. Mai 1995  相似文献   
45.
The effect of pH onH. pylori urease activity in its ecological niche was studied in gastric antral biopsy specimens. Specimens were incubated in 10 mmol/liter urea solutions at pH range 3.3–8.2. Activity of urease was studied by measuring production of ammonia and change in pH of the solutions. Urease activity was reduced at pH 8.2 (1424 ± 218 µmol/liter) but decreasing initial pH to neutral and acidic values resulted in significant maximal 6.5-fold increase in ammonia production (9491 ± 1073 µmol/liter,P<0.0005), which considerably raised the pH of the test solutions. Peak urease activity was between pH 5.0 and 7.0. In contrast to specimens incubated initially at pH 8.0, reincubation of washed specimens from solutions with initial pH 7.0 showed eightfold decreased urease activity. It is concluded that urease activity is markedly pH dependent with pH optima below the physiological mucosal surface pH. Furthermore, availability of urease is limited. Thus, an impaired gastric mucosal integrity allowing back diffusion of hydrogen ions may release urease activity, which might further weaken the mucus barrier and damage the gastric epithelium.This study was supported by the Deutsche Forschungsgemeinschaft (Mi 190/3).  相似文献   
46.
The vacuolating cytotoxin and urease secreted by Helicobacter pylori are thought to be virulent factors. Because vacuolation is potentiated by the presence of ammonium ion, which is produced by urease in vitro, it is of interest to examine whether cytotoxin and urease work reciprocally in the development of atrophic gastritis or duodenal ulcer. In the present study, patients (all H. pyloripositive) were divided into four groups: mild atrophic gastritis (group 1; nine patients), severe atrophic gastritis (group 2; 36 patients), duodenal ulcer with mild atrophic gastritis (group 3; 19 patients) and duodenal ulcer with severe atrophic gastritis (group 4; 12 patients). Cytotoxin production and urease activity of H. pylori isolated from these patients were analysed. Cytotoxin production was observed in four of nine (44.4%), 28 of 36 (77.8%), 11 of 19 (57.9%) and eight of 12 (66.7%) isolates from groups 1, 2, 3 and 4, respectively. Cytotoxin-producing H. pylori isolates were found significantly more in patients with severe atrophy than in patients with mild atrophy (P= 0.048). The mean of relative activity of cytotoxin in H. pylori isolate was 1. 6. ± 2. 3, 7. 9. ± 7. 4, 5. 8. ± 6. 0 and 9. 0 ± 9. 1 in groups 1, 2, 3 and 4, respectively. Helicobacter pylori isolates from severe atrophy or duodenal ulcer patients in groups 2 or 4 possessed significantly higher activity than those from non-ulcer patients in group 1 (P= 0.017 and 0.030, respectively). The mean of urease activity was 8. 6 ± 4. 6, 10. 0 ± 5. 9, 10. 0 ± 8. 5 and 11. 2 ± 7. 7 IU/mg in groups 1, 2, 3 and 4, respectively. These differences indicated no statistical significance. In each H. pylori isolate, the production of cytotoxin and urease were independent, which indicated that there was no reciprocal effect between them in vivo. Thus, cytotoxin-producing H. pylori isolates were more prevalent in patients with severe atrophic gastritis and the cytotoxin activities of H. pylori isolates from the patients with severe atrophic gastritis or duodenal ulcer were much higher than those from the patients with mild atrophic gastritis, which suggested that vacuolating cytotoxin may be a disease-inducing factor.  相似文献   
47.
 Long-term treatment with proton pump inhibitors in patients with Helicobacter pylori gastritis can lead to atrophic changes in the corpus mucosa. What is still unclear, however, is whether this atrophy can regress in response to Helicobacter pylori eradication. We report on a male patient with Helicobacter pylori gastritis receiving long-term treatment (4 years) with omeprazole for gastro-oesophageal reflux disease, who developed autoaggressive gastritis with progressive atrophy, hypochlorhydria, hypergastrinaemia and nodular ECL-cell hyperplasia. To determine whether these changes might be induced to regress, Helicobacter pylori eradication therapy was administered. Ten months after Helicobacter pylori eradication autoaggressive lymphocytic infiltrates were no longer detectable, and the glands in the corpus mucosa had normalised despite continued treatment with omeprazole – a finding that was confirmed at two further follow-up surveys performed at 6-month intervals. This case report shows that atrophy of the corpus mucosa developing under long-term treatment with a proton pump inhibitor can be cured by eradicating Helicobacter pylori. Received: 21 April 1998 / Accepted: 10 August 1998  相似文献   
48.
Jarvis D  Luczynska C  Chinn S  Burney P 《Allergy》2004,59(10):1063-1067
BACKGROUND: A negative association of oro-faecally spread infection with serological markers of sensitization and allergic disease has been reported. METHOD: Previous infection with hepatitis A and Helicobacter pylori was assessed in a community-based sample of young British adults and associations with serum-specific IgE to environmental allergens, asthma-like symptoms and hay fever were examined. RESULTS: There was no association of previous infection with hepatitis A or H. pylori with wheeze or hay fever. There was no evidence of an association of infection with either agent and sensitization except for the isolated finding of a lower prevalence of sensitization to grass in those with IgG antibodies to H. pylori (OR 0.65, 95% CI 0.43-0.99). This association did not explain the negative association of family size with sensitization to grass. CONCLUSION: In this population, there was no evidence that infection with hepatitis A or H. pylori was associated with lower levels of IgE sensitization, asthma or hay fever except for an isolated finding of a negative association of H. pylori infection with sensitization to grass.  相似文献   
49.
Helicobacter pylori has been shown to be strongly associated with chronic gastritis, gastric and duodenal ulceration, and is a risk factor for gastric carcinoma. Histology, urease, culture, and polymerase chain reaction have been employed as for H. pylori diagnostic methods, pre and post treatment or during follow-up of dyspeptic adult individuals referred for endoscopy. In order to obtain a more-sensitive and specific method for H. pylori detection, we evaluated gastric body and antrum biopsies of 134 consecutive Brazilian consecutive dyspeptic children aged 1-16 years by rapid urease test, histology and polymerase chain reaction using two pairs of oligonucleotides. Our results indicated that polymerase chain reaction with Southern blotting and hybridization with specific chemiluminescent probes increased the number of positive H. pylori patients by 35%. The genotyping of H. pylori strains directly from gastric biopsy using the same nucleic acid methodology revealed that there is no association of chronic gastritis in our infant patients with vacA s1 and the presence of the cagA gene. These data suggest an initial infection of children with normal mucosa and probably others factors than vacA s1 genotype or the presence of the cagA gene are associated with the onset of gastric disease. Altogether, our results reinforce the need for using more sensitive diagnostic methods in order to understand the role of H. pylori in the genesis of gastric disease in children and its progression in adults.  相似文献   
50.
幽门螺旋杆菌对慢性胃炎患者胃窦黏膜内G、D细胞的影响   总被引:2,自引:0,他引:2  
目的 了解幽门螺旋杆菌 (HP)对慢性胃炎胃窦黏膜内G、D细胞的影响。 方法 用免疫组织化学双重染色法 ,观察正常人、HP- 组和HP+ 组慢性胃炎患者胃窦黏膜内G、D细胞的数量 ,G D细胞的比值以及G、D细胞接触的百分率。 结果 G细胞数量在 3组中无明显差异 (P >0 0 5 ) ,HP+ 胃炎组D细胞显著减少 ,与其他 2组相比有显著性差异 (P <0 0 1) ;而G D细胞比值增高 ,G、D细胞接触的百分率下降。 结论 HP可抑制胃窦D细胞生长抑素的合成和D细胞的增殖 ,从而可能减少D细胞对G细胞胃泌素分泌的抑制。  相似文献   
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