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101.
The fact thatH. pylori gastritis results in an increased secretion of basal and meal-stimulated gastrin, which is also a physiologic amplifier of insulin release directed us to investigate whetherH. pylori gastritis may lead to an enhancement of nutrient-stimulated insulin secretion. For this purpose, we have investigated the insulin responses to both oral glucose and a mixed meal in 15 patients withH. pylori gastritis before and one month after the eradication therapy and also in 15H. pylori-negative control subjects. The areas under the curve (AUC) for serum insulin following both oral glucose and a mixed meal in the patients withH. pylori gastritis before the eradication were significantly (P<0.05) higher than those in theH. pylori-negative controls. After the eradication ofH. pylori, the AUC for serum insulin following oral glucose and mixed meal decreased by 9.4% and 13.1%, respectively (P<0.001 in both), and serum basal and meal-stimulated gastrin levels decreased significantly (P<0.001). These results suggest thatH. pylori gastritis enhances glucose and meal-stimulated insulin release probably by increasing gastrin secretion.Presented in part as an abstract at the 8th Balkan Congress of Endocrinology, Bursa, Turkey, May 3–5, 1995.  相似文献   
102.
We report the coexistence of symptomatic viral, bacterial, and fungal infection of the upper gastrointestinal tract in a heart transplant recipient. Endoscopic findings were normal at all levels but, because of severe symptoms and recent conversion to positive serology forCytomegalovirus, biopsies were taken. These showed esophageal candidiasis and gastricHelicobacter infection that has hitherto been unreported in cardiac transplant recipients.  相似文献   
103.
The stomach is a hostile environment for most microbes because strong gastric acid kills indigenous microorganisms. Thus, the mass of indigenous microbes detected by traditional culturing method in a highly acidic stomach is reported to be very small. However, in a stomach with less acidity due to atrophic changes of the gastric mucosa, the number of live gastric microbiota dramatically increases and their composition changes. A probiotic is defined as a live microorganism that, when administered in adequate amounts, confers a health benefit on the host. The administration of probiotics to the stomach has thus far been considered impractical, mainly due to the strong acidity in the stomach. The identification of candidate probiotic strains with sufficient resistance to acidity and the ability to achieve close proximity to the gastric mucosa could enable the application of probiotics to the stomach. The utilization of probiotics alone for Helicobacter pylori (H. pylori) infection significantly improves gastric mucosal inflammation and decreases the density of H. pylori on the mucosa, although complete eradication of H. pylori has not yet been demonstrated. The use of probiotics in combination with antimicrobial agents significantly increases the H. pylori eradication rate, especially when the H. pylori strains are resistant to antimicrobial agents. While H. pylori has been considered the most important pathogenic bacterium for the development of gastric cancer, bacteria other than H. pylori are also suggested to be causative pathogens that promote the development of gastric cancer, even after the eradication of H. pylori. Increased non-H. pylori Gram-negative bacteria in the stomach with weak acidity accompanying atrophic gastritis may perpetuate gastric mucosal inflammation and accelerate carcinogenic progression, even after H. pylori eradication. Probiotics restore the acidity in this stomach environment and may therefore prevent the development of gastric cancer by termination of Gram-negative bacteria-induced inflammation. Functional dyspepsia (FD) is defined as the presence of symptoms that are thought to originate in the gastroduodenal region in the absence of any organic, systematic or metabolic diseases. Accumulating evidence has pointed out the duodenum as a target region underlying the pathophysiology of FD. A randomized placebo-controlled clinical trial using a probiotic strain (LG21) demonstrated a significant improving effect on major FD symptoms. One of the possible mechanisms of this effect is protection of the duodenal mucosa from injurious intestinal bacteria through the resolution of small intestinal bacterial over growth.  相似文献   
104.
Epstein-Barr virus (EBV)-associated gastric cancer (EBVaGC) cells originate from a single-cell clone infected with EBV. However, more than 95% of patients with gastric cancer have a history of Helicobacter pylori (H. pylori) infection, and H. pylori is a major causative agent of gastric cancer. Therefore, it has long been argued that H. pylori infection may affect the development of EBVaGC, a subtype of gastric cancer. Atrophic gastrointestinal inflammation, a symptom of H. pylori infection, is observed in the gastric mucosa of EBVaGC. Therefore, it remains unclear whether H. pylori infection is a cofactor for gastric carcinogenesis caused by EBV infection or whether H. pylori and EBV infections act independently on gastric cancer formation. It has been reported that EBV infection assists in the onco-genesis of gastric cancer caused by H. pylori infection. In contrast, several studies have reported that H. pylori infection accelerates tumorigenesis initiated by EBV infection. By reviewing both clinical epidemiological and experimental data, we reorganized the role of H. pylori and EBV infections in gastric cancer formation.  相似文献   
105.
When several Helicobacter pylori eradication treatments fail, guidelines recommend a cultured guided approach; however, culture is not widely available. Therefore, a rifabutin based regimen could be the best solution. Rifabutin indeed shows a low rate of antibiotic resistance. Rifabutin is generally used in combination with amoxicillin in a triple therapy, with eradication rates about 80% in third-line regimens. The ideal duration of this therapy should range between 10 and 12 d. Combinations with antibiotics other than amoxicillin have demonstrated even better results, such as vonoprazan, which is a type of novel acid suppressor drug. Finally, a new formulation of triple therapy in a single capsule is under investigation, which is a field that deserves further investigation. Some notes of caution about rifabutin should be mentioned. This drug is used to treat tuberculosis or atypical mycobacteria; therefore, before starting a rifabutin-based eradication regimen, Mycobacterium tuberculosis infection should be thoroughly tested, since its use could promote the development of antibiotic resistance, thus affecting its effectiveness against Koch’s bacillus. Additionally, some serious side effects must be evaluated before starting any rifabutin-based therapy. Adverse effects include fever, nausea, vomiting and bone marrow suppression. For this reason, full blood count surveillance is required.  相似文献   
106.
The aims of the study were to evaluate the diagnostic accuracy of a rapid whole blood test (one-step BM-Test Helicobacter pylori) in different blood collections and compare it with a quantitative ELISA test (HEL-p TEST II). One hundred four dyspeptic patients were studied, and 53 (51%) were H. pylori-positive as determined by [13C] urea breath test. The area under the ROC curve was higher for HEL-pTEST II compared to the one-step BM-Test with either fingerstick or venipuncture (0.972 vs 0.721 and 0.714, P = 0.000). The most appropriate cutoff reading time was 5 min for the one-step BM-Test. The sensitivity, specificity, and accuracy were 52.8%, 88.2%, 70.2% for fingerstick; 62.3%, 80.4%, 71.2% for venipuncture; and 90.6%, 92.2%, 91.3% for HEL-pTEST II. We conclude that there is no difference in diagnostic performance between capillary and venous blood for rapid whole blood test, and extending the reading time beyond the manufacturer's suggestion for the one step BM-Test does not improve its accuracy.  相似文献   
107.
The hypergastrinemia and hyperacidity associated with Helicobacter pylori infection has been explained by either a primary excess of gastrin or a lack of inhibitory influence by somatostatin (SOM). The objective of the present study was to compare the concentrations of fundic and antral SOM- and antral progastrin-derived peptides in nonulcer dyspepsia (NUD) subjects with and without H. pylori infection. Antral and fundic mucosal biopsies were extracted and assayed for SOM and gastrin amide, glycine–extended gastrin (gastrin gly), progastrin, and total gastrin. There was a significant sixfold reduction in antral SOM but no change in fundic SOM content in H. pylori-infected subjects compared to uninfected subjects. Antral gastrin amide concentrations were significantly higher in infected subjects. However, the concentrations of the nonamidated gastrin forms (progastrin and glycine-extended gastrin) were significantly lower in the infected subjects, indicating an increased conversion of the precursor forms of gastrin to amidated gastrin, the type known to stimulate gastric acidity. The present study demonstrates that the elevated gastrin concentrations associated with H. pylori infection may be due to a reduction in the paracrine inhibitory effect of SOM on antral gastrin release. In addition, the posttranslational processing of gastrin to the amidated forms is increased in infected subjects, explaining why the elevation in antral gastrin is confined to the amidated form.  相似文献   
108.
MYC is an oncogene involved in cell cycle regulation, cell growth arrest, cell adhesion, metabolism, ribosome biogenesis, protein synthesis, and mitochondrial function. It has been described as a key element of several carcinogenesis processes in humans. Many studies have shown an association between MYC deregulation and gastric cancer. MYC deregulation is also seen in gastric preneoplastic lesions and thus it may have a role in early gastric carcinogenesis. Several studies have suggested that amplification is the main mechanism of MYC deregulation in gastric cancer. In the present review, we focus on the deregulation of the MYC oncogene in gastric adenocarcinoma carcinogenesis, including its association with Helicobacterpylori (Hpylon] and clinical applications.  相似文献   
109.
BACKGROUND: Studies on the incidence of perforated duodenal ulcer are limited and in the United Kingdom, data are largely based on findings observed over two decades ago. To provide updated epidemiological data on duodenal ulcer perforation, the incidence of the disease in Norfolk, United Kingdom was determined. METHODOLOGY: Medical records of patients with duodenal ulcer perforation were reviewed to confirm the diagnosis and obtain information on possible risk factors, namely, Helicobacter pylori infection, smoking and intake of non-steroidal anti-inflammatory drugs. The patients were admitted between 1 January 1996 and 31 December 1998, and were residents of Norfolk, United Kingdom. RESULTS: Sixty-eight cases of duodenal ulcer perforation were identified, 36 (52.9%) were males and 32 (47.1%) were females. The age-standardised incidence rate was 3.77 per 100,000 population per year (95% confidence interval 3.72-3.83). The mean age upon admission for all cases was 72.3 years (standard deviation: 17.8). The mean age for males was 67.7 years (standard deviation: 19.4) and for females 77.6 years (standard deviation: 15.7), which differed significantly (difference in means: 9.9, 95% confidence interval 1.5-18.3). There were 29 deaths (42.7%), of which 19 were females. After adjustment for covariates, the odds ratio of mortality in women was 4.57 (95% confidence interval 1.28-16.29). There were 25 (36.8%) smokers and 22 (32.4%) patients were non-steroidal anti-inflammatory drug users. Helicobacter pylori infection was assessed in only 14 (20.6%) patients; 2 were positive, 3 were negative, and in the rest the results were unrecorded. CONCLUSIONS: The incidence rates were lower compared to previous studies in the United Kingdom conducted in the 1960's and 1980's, which could reflect either improved health care or decreasing exposure to known risk factors. Furthermore, the difference in age distribution of incident cases between males and females may explain the higher mortality in females.  相似文献   
110.
根除幽门螺杆菌对消化性溃疡合并胃炎及胃泌素的影响   总被引:8,自引:0,他引:8  
目的 :评估胃舒散联合呋喃唑酮、阿莫西林对消化性溃疡 (PU)患者Hp根除的效果及其对溃疡合并胃炎、血清胃泌素(Gas)的影响。方法 :77例Hp阳性十二指肠溃疡组 (DU ,52例 )和胃溃疡组 (GU ,2 5例 )患者 ,均服用胃舒散 2 .0g(含铋 0 .1 2g) ,呋喃唑酮0 .1g,阿莫西林 0 .5g ,各 3次 /d ,2周后再继服胃舒散 4周。治疗前及疗程结束 1月后进行内镜检查并对胃窦、胃体胃炎予以内镜下评分。采用放射免疫法于治疗前及结束 1月、6月后检测胃泌素水平。结果 :DU组与GU组溃疡愈合率分别为 1 0 0 %和 92 % ,Hp根除率分别为 90 .3 %和 84.0 % ,二组比较差异均无显著性 (P >0 .0 5)。将根除Hp的 47例DU和 2 1例GU患者分为 2组 ,治疗前 2组胃窦胃炎的评分差异无显著性 (P >0 .0 5) ;GU组胃体胃炎的评分显著高于DU组 (P <0 .0 0 1 ) ;血浆中胃泌素含量 (DU组 39.4± 1 3 .6pg/ml;GU组38.4± 1 2 .3pg/ml)均显著高于正常对照值 (2 8.5± 1 0 .6pg/ml,P <0 .0 5)。Hp根除 1月后 ,2组患者胃窦胃炎与胃体胃炎的评分均显著下降 ,与治疗前自身比较 ,差异有统计学意义 (均P <0 .0 0 1 )。DU组Hp根除治疗 1月后 ,胃泌素水平显著下降到 32 .7± 1 0 .5pg/ml (P <0 .0 5)。GU组Hp根除 1月后 ,胃泌素水平有所下降 ,但与治疗前相比 ,差  相似文献   
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