Oesophageal acid exposure: higher in Barrett's oesophagus than in reflux oesophagitis

Oesophageal acid exposure at different pH intervals between 0 and 8 in patients with Barrett's oesophagus (n = 24) was compared with that in patients with reflux oesophagitis (n = 19) by using 24-h pH monitoring. Prior to the monitoring, the position and pressure of the lower oesophageal sphincter was measured by manometry. Columnar epithelium with intestinal metaplasia and goblet cells was verified histologically in all Barrett patients and grade I-III oesophagitis in patients with reflux oesophagitis. Acid exposure (percentage of total time at pH < 4) in the Barrett group was significantly greater than in the oesophagitis group: 21.5+/-20.0% SD vs 11.1+/-11.7% SD (P < 0.01). The number of reflux episodes lasting longer than 5 min (representing oesophageal body clearance function) was also significantly greater in the Barrett group (8.3+/-5.9 SD) than in the oesophagitis group (4.5+/-4.7 SD) (P < 0.01). In the Barrett group the acid exposure time was greater at all pH intervals 0-1, 1-2, 2-3 and 3-4, (P < 0.01) but in the oesophagitis group the exposure time was greater at pH interval 5-6 (P < 0.01). There was no significant difference in exposure at pH values above 7. The mean lower oesophageal sphincter pressure was equal in both groups (11.0 vs 11.9 mmHg). In conclusion, oesophageal acid exposure was significantly greater in Barrett's oesophagus than in reflux oesophagitis, and this was associated with decreased oesophageal clearance function. In addition, the results indicated the need for special attention and perhaps higher dosages of drugs to suppress acid production in patients with Barrett's oesophagus.     

Barrett's Oesophagus Is Not a Risk Factor for Colonic Neoplasia: A Case-control Study

Previous uncontrolled studies have suggested that patients with Barrett's oesophagus have an increased risk of colonic neoplasia. The present study was undertaken to clarify the occurrence of colorectal neoplasms in patients with Barrett's oesophagus and asymptomatic controls.

Colonoscopy in 72 consecutive patients with Barrett's oesophagus and in 27 controls, none with symptoms of colonic neoplasm, revealed colorectal adenoma(s) in 17 cases (24%) in patients with Barrett's oesophagus and in eight (30%) controls. All 34 adenomas were less than 2 cm in diameter, with 30 less than 1 cm. None was malignant. Using logistic regression model with occurrence of colonic adenoma as dependent and sex, age and occurrence of Barrett's oesophagus as explanatory variables, none of these was found to be a significant risk factor for the appearance of colonic adenoma. The study thus suggests that Barrett's oesophagus is not associated with increased risk of colorectal neoplasm. Colonoscopic surveillance of patients with Barrett's oesophagus is not justified.     

Esomeprazole in acute and maintenance treatment of reflux oesophagitis: a multicentre prospective study

INTRODUCTION: The aim of this study was to assess the efficacy and safety of esomeprazole 40 mg once daily (q.d.) in healing reflux oesophagitis at 4 and 8 weeks, and the efficacy of esomeprazole 20 mg q.d. for 12 weeks in the maintenance of remission. METHODS: A total of 235 patients with endoscopically proven reflux oesophagitis were enrolled in this study, which consisted of two phases (healing and maintenance therapy). Patients who showed complete endoscopic and symptomatic healing at the end of 4 or 8 weeks were switched to maintenance treatment with esomeprazole 20 mg q.d. for 12 weeks. The primary efficacy endpoint was healing of reflux oesophagitis at week 8. Secondary assessments included the proportion of patients with symptomatic relapse in the maintenance phase. RESULTS: At the end of week 8, 88% (95% life-table confidence intervals [CI]: 84%, 92%) of patients were healed endoscopically and 90.6% of the patients were asymptomatic. Patient age, gender and Helicobacter pylori status had no effect on the efficacy of treatment. During the 12-week maintenance treatment phase, symptomatic relapse ratios were 0.5%, 2.2%, and 0%, for the first, second, and third 4-week periods, respectively. The proportions of patients satisfied with treatment were 95% and 99.4% at the end of acute and maintenance treatment, respectively. The most common adverse effects were headache, upper respiratory tract infection and abdominal pain. CONCLUSIONS: Esomeprazole is effective in the healing of reflux oesophagitis, the resolution of heartburn, and in maintaining symptomatic remission. The effectiveness of esomeprazole in patients with gastroesophageal reflux disease is not affected by the presence of H. pylori.     

提高透析液钙浓度对透析中低血压患者血流动力学的影响

目的 对反复出现透析中低血压的维持性血液透析患者,提高透析液钙浓度,观察透析过程的血流动力学稳定性.方法 本研究采用前瞻性、单中心、前后交叉自身对照研究方式,将四川大学华西医院透析中心符合纳入标准的透析中低血压(intra-dialysis hypotension,IDH)患者随机分为2组.A组患者分别予以低钙、中钙、高钙的透析液各进行2周透析,B组患者分别予以高钙、中钙、低钙的透析液各进行2周透析.2组患者均每周透析3次,每次4h.记录透析前与透析过程中的收缩压、舒张压与心率、透析前血压与透析中最低血压差值(△P);记录透析过程中症状性低血压、提前停止透析事件的发生率.结果 共有16例IDH患者符合纳入标准,其中2例因发生感染退出,其余14例患者均完成研究.与中钙透析液相比,高钙透析液提高透析过程中的平均收缩压,差别具有显著性差异 (F =3.302,P=0.013),而收缩压差值无显著性差异( F=3.047,P=0.098).与低钙透析液相比,高钙透析液降低透析前与透析中最低血压的收缩压差值有显著性差异( F=3.047,P=0.016),平均收缩压无显著性差异( F=3.302,P=0.073).而中钙透析液与低钙透析液之间透析中平均收缩压、收缩压差值无显著性差异(分别为F=3.302,P=0.457和F =3.047,P=0.479),但对于舒张压、心率的变化以及减少透析不良事件的发生率无显著作用.结论 通过3种钙浓度的比较,高钙透析液对提高透析中低血压患者血流动力学稳定性有一定改善,但不能减少透析中症状性低血压的发生,改善透析充分性.高钙透析液对顽固透析中低血压患者血流动力学方面的作用,尚需要多中心、大样本的临床研究来明确.     

幽门螺杆菌感染对胃食管反流病患者食管酸暴露及食管动力的影响

目的分析幽门螺杆菌（helicobacterpylor,Hp）感染胃食管反流病（gastroesophagealrefluxdisease,GERD）患者食管远端酸暴露及食管动力变化特点,探讨Hp感染与GERD的关系。方法GERD患者80例,分为Hp阳性组30例,Hp阴性组50例,同期20例慢性浅表性胃炎患者为对照组,对3组进行食管动力学检测和食管24hpH监测。结果Hp阳性组与Hp阴性组DeMeester评分、食管下括约肌压力、24hpH监测各项指标及食管动力学各项指标比较差异均无统计学意义（P〉O．05）;2组DeMeester评分均高于对照组（P〈0．05）,食管下括约肌压力低于对照组（P〈0．05）。结论GERD患者食管下括约肌压力较正常人群低,且存在过量酸反流;Hp感染与GERD发生可能无明显关系。     

A novel H(+) conductance in eosinophils: unique characteristics and absence in chronic granulomatous disease.

Efficient mechanisms of H(+) ion extrusion are crucial for normal NADPH oxidase function. However, whether the NADPH oxidase-in analogy with mitochondrial cytochromes-has an inherent H(+) channel activity remains uncertain: electrophysiological studies did not find altered H(+) currents in cells from patients with chronic granulomatous disease (CGD), challenging earlier reports in intact cells. In this study, we describe the presence of two different types of H(+) currents in human eosinophils. The "classical" H(+) current had properties similar to previously described H(+) conductances and was present in CGD cells. In contrast, the "novel" type of H(+) current had not been described previously and displayed unique properties: (a) it was absent in cells from gp91- or p47-deficient CGD patients; (b) it was only observed under experimental conditions that allowed NADPH oxidase activation; (c) because of its low threshold of voltage activation, it allowed proton influx and cytosolic acidification; (d) it activated faster and deactivated with slower and distinct kinetics than the classical H(+) currents; and (e) it was approximately 20-fold more sensitive to Zn(2+) and was blocked by the histidine-reactive agent, diethylpyrocarbonate (DEPC). In summary, our results demonstrate that the NADPH oxidase or a closely associated protein provides a novel type of H(+) conductance during phagocyte activation. The unique properties of this conductance suggest that its physiological function is not restricted to H(+) extrusion and repolarization, but might include depolarization, pH-dependent signal termination, and determination of the phagosomal pH set point.