Pressure overload-induced transient oxidative stress mediates perivascular inflammation and cardiac fibrosis through angiotensin II.

Oxidative stress is implicated in the pathogenesis of various cardiovascular diseases. We have shown that in Wistar rats with a suprarenal aortic constriction (AC), pressure overload-induced transient perivascular inflammation (monocyte chemoattractant protein-1 [MCP-1] induction and macrophage accumulation) in the early phase is the determinant of reactive myocardial fibrosis and resultant diastolic dysfunction in the late phase. Thus, we investigated the role of reactive oxygen species production in cardiac remodeling in AC rats. Superoxide production and the footprint of lipid peroxidation were assessed using dihydroethidium staining and immunohistostaining against 4-hydroxy-2-nonenal (4-HNE), respectively. In sham rats, dihydroethidium and 4-HNE signals were scarcely found in the heart. At day 3, AC rats showed dihydroethidium signals mainly in the intramyocardial arterial wall, whereas modest 4-HNE staining was observed diffusely in the myocardium. These signals declined to lower levels by day 14 despite sustained hypertension. Chronic administration of a subdepressor dose of an angiotensin II type 1 receptor blocker candesartan reduced the pressure overload-induced dihydroethidium and 4-HNE signals at day 3. Moreover, candesartan decreased MCP-1 induction and macrophage infiltration at day 3 and prevented myocardial fibrosis at day 14, without affecting left ventricle and myocyte hypertrophy. In conclusion, acute pressure overload induced self-limited superoxide production mainly in the vascular wall. The reactive oxygen species production would contribute to the perivascular inflammation and subsequent myocardial fibrosis. Angiotensin II was suggested to have a pressure-independent effect on the reactive oxygen species production.     

类风湿病中左心室收缩功能障碍：一种未被认识的负荷？

目的:本研究旨在明确左心室收缩功能障碍在临床类风湿病(RD)患者中是否较正常人群中更常见,并评价脑利钠肽(BNP)的诊断价值。背景:RD患者罹患缺血性心脏病的风险增加,而采用超声心动图评估RD患者心功能不全的大型研究却少见。假定左心室收缩功能障碍在RD患者中较正常人群中更为     

兔关节软骨细胞的分离、培养和形态学特征

[目的]探讨兔关节软骨细胞的分离、培养方法,观察单层高浓度培养时细胞表型表达情况.[方法]无菌条件下,从 2周龄新西兰白兔的颞颌关节及四肢关节髁突面削取软骨片,采用机械-酶消化法分离软骨细胞,经台盼蓝拒染计数,将细胞按 1× 106个 /孔接种于 6孔培养板,传代培养,描绘生长曲线.利用相差显微镜及透射电镜观察细胞形态.应用甲苯胺蓝及Ⅱ型胶原免疫组化对细胞进行鉴定.[结果]每克软骨能获取 1 5× 106个软骨细胞,活性率为 95%.培养 2～ 3 d,细胞贴壁、变形,呈多角形; 8 d左右,细胞融合成层.透射电镜观察显示细胞核圆形,有丰富的粗面内质网、高尔基体及分泌的基质成分.甲苯胺蓝及Ⅱ型胶原染色阳性.细胞传至 5代后,出现"成纤维细胞样".[结论]本研究建立了简单易行的软骨细胞分离、培养方法;初代、第 2代细胞生长良好,适合于实验研究;软骨细胞 5代培养后,细胞表型发生改变.     

视场角设置对虚拟环境中目标判断的影响

目的探讨不同视场角参数对虚拟环境中目标判断的影响规律 ,找出最佳视场角参数。方法利用自行研制基于PC平台的虚拟现实 (VR)实验系统 ,选定 45名年龄在 2 3～ 5 8岁被试者并完成大小与角度判断的实验设计。首先进行 30 0人次的预实验 ,确定引起虚拟环境中目标判断差错的视场角及相应观察任务的差别等级 ,然后开始单因素、4水平的完全随机正式实验。结果方差分析表明 ,不同的虚拟环境视场角对目标判断的真实性有显著性影响 ,当视场角为 60°时 ,目标判断的正确率最大。结论利用VR技术进行载人航天器工效设计、操作训练或其它任务的研究时 ,应考虑视场角的作用 ,适合目标大小判断的视场角参数值宜取 60°,以便获得最大的工效     

全面康复:勃起功能障碍治疗的新目标

5型磷酸二酯酶(PDE5)抑制剂有效改善勃起功能障碍(ED)患者的勃起功能。枸橼酸西地那非的应用范围不断扩展,肺动脉高压已成为新的适应证。临床研究发现,西地那非能改善多种血管性疾病患者的内皮功能。在ED领域的研究进展包括:动物实验发现,西地那非可以改善海绵体内皮功能,增强磷酸化内皮型一氧化氮合酶(eNOS)蛋白表达,逆转缺血或缺氧导致的海绵体内压(ICP)降低。临床研究证实,西地那非可以使50%以上ED患者阴茎勃起恢复到最充分的硬度(4级勃起);使50%以上保留神经的根治性前列腺切除术后患者勃起功能康复,自发产生足以性交的勃起;使ED患者的自尊心、自信心和性关系满意度等社会心理功能恢复正常。从勃起功能到社会心理功能的全面恢复可能成为今后ED治疗的新目标。     

Effects of endotoxin on intestinal hemodynamics, glutamine metabolism, and function

The purpose of this study was to investigate the intestinal hemodynamics and gut glutamine metabolism during endotoxemia, and their correlation with altered intestinal absorptive capacity and permeability. Seventeen Sprague-Dawley rats were used in the study. The endotoxin group (ENDO) recieved endotoxin (10 mg/kg intraperitoneally,n=9), while the control group (CONT,n=8) received saline injection. Twelve hours later, D-xylose (0.5 g/kg) and fluorescein isothiocyanate-dextran (FITC-dextran, 750 mg/kg) were given by oral gavage. One hour later abdominal aortic (AA) blood flow, superior mesenteric venous (SMV) flow, mean arterial pressure (MAP), central venous pressure (CVP), and SMV pressure (SMVP) were also measured. The MAP, AA, and SMV blood flow decreased (P<0.05), while the CVP and SMVP increased (P<0.05) in the ENDO group as compared with the CONT group. The ENDO group showed significant decreases for both intestinal glutaminase activity and net intestinal glutamine uptake (P<0.05). The D-xylose concentration in SMV decreased significantly (P<0.05) in the ENDO group as compared with the CONT group. However, the plasma FITC-dextran concentration showed no significant difference between the groups. Endotoxin produced a hypodynamic effect in rats 12h after intraperitoneal administration in association with both a decreased intestinal glutamine metabolism and an absorptive capacity.     

一种胰岛素抵抗的糖尿病特殊类型报告

报告５例对胰岛素抵抗的糖尿病特殊类型病例，其均具有胰岛素应用指征，但使用胰岛素后血糖却反而上升，逐渐增加胰岛素用量，则血糖值亦呈上升趋势。对该类病人的治疗，首先停用胰岛素，改用自制中药制剂及优降糖、降糖灵治疗，取得了良好效果。     

上睑下垂78例手术分析

用额肌悬吊术或提上睑肌缩短术治疗７８例上睑下垂病例，治愈７眼，基本治愈１２眼，矫正不足３眼，矫正过度２眼，笔者认为，术前分析病因；注意提上睑肌肌力的测定；采用适当的手术方法，是手术成功的关键。     

人类转移癌间质淋巴样细胞漫润及其意义的探讨

观察126例人类转移癌,分析比较淋巴样细胞浸润(LI)程度与患者年龄、病理类型、组织分化和核异型程度的关系。结果表明:患者年龄及病理类型与LI程度无关;组织分化程度在LI上虽有差别,但无对应性关系;而核异型程度与LI关系密切。核异型性愈明显,LI程度愈高,反之亦然。这说明核分级不仅可以反映宿主免疫反应的高低,也可提示转移癌抗原性的强弱。     

股骨头缺血性坏死的CT诊断

本文报告了19例股骨头缺血性坏死的CT及多平面重建和三维CT成像表现,并探讨其对术前病变评估的价值,在显示Ⅱ期病变时CT明显优于平片,多平面重建有利于发现股骨头塌陷、关节间隙改变和髋臼改变,三维CT可作为一种补充检查手段。