脑出血大鼠脑组织膜型基质金属蛋白酶、基质金属蛋白酶2和基质金属蛋白酶9表达及益气活血中药的干预效应

目的:观察益气活血中药对脑出血大鼠脑组织中膜型基质金属蛋白酶、基质金属蛋白酶2和基质金属蛋白酶9表达量的影响,从脑出血损伤区微血管系统重建的角度,探讨益气活血中药治疗脑出血的作用机制。方法:实验于2006-03/10在中南大学湘雅医院中西医结合研究所实验室完成。实验材料:补阳还五汤全方(黄芪,当归,赤芍,红花,川芎,地龙,桃仁按20∶3∶3∶3∶2∶3∶3的比例);补阳还五汤益气成分(黄芪按上述比例);补阳还五汤活血成分(当归,赤芍,地龙,川芎,桃仁,红花按3∶3∶3∶2∶3∶3的比例)。用蒸馏水两次水煎,分别浓缩为1.54,0.81和0.73g/mL。实验分组:155只SD大鼠随机分为正常对照组、假手术组、模型组、益气活血组、益气组、活血组。正常对照组5只大鼠,其余每组30只,再随机分为术后灌胃2,4,7,14,21,28d6个观察时间点,各个时间点5只大鼠。实验干预:造模:采用立体定位技术将胶原酶Ⅶ注入大鼠大脑右苍白球制成脑出血大鼠模型。假手术组大鼠仅注入2μL生理盐水,其余手术过程相同。给药:正常对照组:普通饲养,自由饮水;假手术组和模型组术后予蒸馏水灌胃2次/d,2mL/次;益气活血组、益气组、活血组分别给予补阳还五汤全方、补阳还五汤益气成分、补阳还五汤活血成分30.80,16.20,14.60g/(kg·d)(按体表面积计算为临床70kg成人剂量的3倍)灌胃,2次/d,2mL/次。各组大鼠分别于灌胃2,4,7,14,21,28d麻醉下取脑,制备切片;正常组动物于28d处死。实验评估:免疫组织化学染色方法检测各组灌胃不同时间脑组织基质金属蛋白酶2、基质金属蛋白酶9和膜型基质金属蛋白酶的阳性微血管数。结果:155只大鼠均进入结果分析。①正常组、假手术组皮质偶见膜型基质金属蛋白酶、基质金属蛋白酶2和基质金属蛋白酶9表达。②模型组膜型基质金属蛋白酶、基质金属蛋白酶2呈双峰表达,4d为最高峰,至14～21d再有小高峰出现。③益气活血组给药4d时,膜型基质金属蛋白酶、基质金属蛋白酶2为表达低谷,低于模型组(P<0.01)、益气组和活血组(P<0.05);在中后期,益气活血组膜型基质金属蛋白酶表达高峰为7～14d,较模型组提前出现,21d后与模型组比,各治疗组膜型基质金属蛋白酶已表达极少(P<0.01);益气活血组基质金属蛋白酶2在7d后一直呈高水平维持,高于其他各组(P<0.05),28d后开始逐渐下降。④模型组基质金属蛋白酶9在造模后4d达最高峰(P<0.01),两周后几乎无表达。益气活血组基质金属蛋白酶9高峰推迟至7d出现(P<0.05),之后逐渐下降。结论:益气活血中药可通过调节脑出血后膜型基质金属蛋白酶、基质金属蛋白酶2和基质金属蛋白酶9表达,改善出血后脑组织的微环境,有利于微血管系统重建,促进组织修复。     

Timing of operation in asymptomatic severe aortic stenosis

Calcific aortic stenosis is now the main cause of aortic stenosis in the majority of patients, due to declining incidence of rheumatic fever. Risk factors such as hyperlipidemia play an important role in the progression of aortic stenosis. According to the most recent American College of Cardiology/American Heart Association guidelines, peak velocity greater than 4 m/sec, a mean gradient of more than 40 mmHg and a valve area of less than 1.0 cm(2) is considered hemodynamically severe aortic stenosis. Aortic valve surgery promptly should be done in symptomatic patients due to dismal prognosis without operation. Features such as high aortic valve calcium and positive exercise test identify asymptomatic patients who would benefit from early aortic valve surgery. Due to improvement in surgical techniques and better prosthesis, aortic valve surgery can now be offered at low risk to a selected group of asymptomatic patients with severe aortic stenosis. Currently percutaneous aortic valves are used in very high-risk patients with severe symptomatic aortic stenosis. Their role may expand in the future, depending on the improvements in design and operator experience. Whether advances in molecular cardiology lead to novel therapies in preventing calcific aortic stenosis in the future remains to be seen.     

Evaluation of acute chest pain syndromes by two-dimensional echocardiography: its potential application in the selection of patients for acute reperfusion therapy

Two-dimensional echocardiography is useful for the immediate diagnosis of acute myocardial infarction when diagnostic electrocardiographic changes are absent. The technique is also helpful in distinguishing myocardial infarction from other conditions that may clinically or electrocardiographically mimic infarction. The extent of myocardial infarction can be estimated by the two-dimensional echocardiographically derived wall motion score index. Therefore, two-dimensional echocardiography seems to be ideally suited for the initial noninvasive assessment of patients with acute chest pain syndromes, especially those who are considered for acute reperfusion therapy.     

骨纤维结构不良的诊断和治疗进展

目的:对长期以来关于骨纤维结构不良大量相关研究及文献进行回顾,综述骨纤维结构不良的诊断和治疗的最新进展。资料来源:通过计算机互联网检索OVID数据库1966-01/2006-10关于骨纤维结构不良的文献,检索词:Osteofibrous dysplasia,限定语言种类为English。同时检索1994-01/2006-10中国全文期刊数据库有关骨纤维结构不良的文献,检索词为:骨纤维结构不良,限定语言种类为中文。资料选择:选择与骨纤维结构不良相关的观察对比研究、经验总结、个案报道、最新研究进展等文献,力求资料全面,排除重复研究。资料提炼:共收集相关国内外文献41篇,排除重复性研究11篇,采用30篇,包括关于骨纤维结构不良定义、发病机制、病理、诊断及治疗等。资料综合:①骨纤维结构不良是一种起源于纤维组织的良性骨肿瘤。发病率低、误诊率高。目前具体发病机制不明,现认为与常染色体显性遗传有关。②骨纤维结构不良好发于胫骨,症状为局部肿块。特征性影像学表现为胫骨中段前侧皮质膨胀性密度减低。确诊方法为病理检查。重点与骨纤维异常增殖症、造釉细胞瘤相鉴别,现有大量研究证明该病与造釉细胞瘤有联系。③治疗上过去认为10岁以前应保守治疗,10岁后选择手术治疗,目前倾向于早期骨膜外切除手术治疗。结论:骨纤维结构不良发病率低,对该病认识较少,误诊率较高,重点需与骨纤维异常增殖症、造釉细胞瘤相鉴别,应提高对该病的认识与重视程度,对可疑者行病理检查,确诊者行骨膜外切除,切除范围较大的病例行重建手术。     

白藜芦醇对动物离体心房收缩力和心率作用的种属差异性比较

目的:观察白藜芦醇对豚鼠、小鼠和家兔离体心肌收缩力和心率的影响。方法:实验于2005-08/2006-12在河北医科大学西校区实验中心完成。①实验分组:离体豚鼠、小鼠和家兔心肌各分为9组:空白对照组、溶剂对照组、递增累积浓度白藜芦醇组(浓度为10-6,3×10-6,10-5,3×10-5,10-4,3×10-4mol/L),白藜芦醇对照组(5×10-5mol/L),ATP敏感性钾通道阻断剂格列苯脲(5×10-5mol/L)预孵育 白藜芦醇组,钙激活钾通道阻断剂四乙胺(10-3mol/L)预孵育 白藜芦醇组,电压依赖性钾通道阻断剂4-氨基吡啶(10-3mol/L)预孵育 白藜芦醇组,内向整流钾通道阻断剂氯化钡(10-4mol/L)预孵育 白藜芦醇组,乙酰胆碱调节钾通道阻断剂阿托品(10-5mol/L)预孵育 白藜芦醇组。②实验方法:不同类型的钾通道阻断剂均预孵育15min后,分别加入白藜芦醇(终浓度为5×10-5mol/L),连续记录30min,与相应动物白藜芦醇对照组相比较。③评估指标:分析不同阻断剂与白藜芦醇联用对心房收缩力下降率及心率抑制率的影响。结果:①白藜芦醇可降低豚鼠和小鼠离体心肌收缩力和心率(P<0.05),并被ATP敏感性钾通道阻断剂格列苯脲和钙激活钾通道阻断剂四乙胺部分阻断。②白藜芦醇可降低家兔离体心肌心率,格列苯脲可阻断白藜芦醇的负性变时作用。③电压依赖性钾通道阻断剂4-氨基吡啶、内向整流钾通道阻断剂氯化钡、乙酰胆碱调节钾通道阻断剂阿托品均不能阻断白藜芦醇对3种不同动物离体心房收缩力和心率的作用(P>0.05)。结论:白藜芦醇可呈剂量依赖性减慢豚鼠、小鼠和家兔的心率,白藜芦醇可减弱豚鼠心肌收缩力,其作用是与开放ATP敏感性钾通道有关,而与电压依赖性钾通道、内向整流钾通道和乙酰胆碱调节钾通道无关。同时,钙激活钾通道也参与了白藜芦醇对豚鼠和小鼠离体心房收缩力和/或心率的抑制作用。白藜芦醇对离体心肌收缩力和心率的作用有种属差异性。     

Diagnostic value of mitral annular velocity for constrictive pericarditis in the absence of respiratory variation in mitral inflow velocity

Respiratory variation of 25% or more in transmitral early diastolic filling (E) velocity is a well-recognized diagnostic feature of constrictive pericarditis (CP) that is useful for distinguishing it from restrictive cardiomyopathy. However, a subset of patients with CP do not exhibit the typical respiratory change. Recent data showed that mitral annular (E') velocity measured by Doppler tissue echocardiography (DTE) is markedly reduced in patients with restrictive cardiomyopathy whereas E' velocity is well-preserved in CP. This study evaluated the role of DTE for the diagnosis of CP when there is no characteristic respiratory variation of E velocity. From September 1999 to March 2001, 19 patients (17 men, 2 women; mean age, 57 +/- 13 years) with surgically confirmed CP underwent comprehensive echocardiography preoperatively, including pulsed wave and DTE examination with simultaneous recording of respiration. Nine (47%) of the 19 patients had less than 25% respiratory variation in E velocity. There was no significant difference in mitral inflow peak velocity, deceleration time, early-to-late ventricular filling ratio, and E' velocity between patients with and patients without respiratory variation of E velocity of 25% or more. Regardless of the presence or absence of a significant respiratory variation of E velocity, E' velocity was relatively normal (mean, 12 +/- 4 cm/s) in all patients with CP. In conclusion, E' velocity is well preserved in patients with isolated CP even when there is no characteristic respiratory variation of E velocity. Thus, when the respiratory variation in Doppler E velocity is blunted or absent during the evaluation of suspected CP in patients with restrictive mitral inflow velocity, preserved E' velocity shown by DTE should support the diagnosis of CP over a primary myocardial disease.     

超声和微泡造影剂介导细胞基因转染的实验研究

目的 探讨低频超声对细胞基因转染的作用。方法 超声治疗仪频率1MHz，脉冲重复频率100Hz，占空系数20％。质粒DNA为含编码绿荧光蛋白的pEGFP。应用荧光显微镜和流式细胞仪评价细胞基因转染率，台盼蓝染色计算细胞成活率。选用C2C12、3T3-MDEI和CHO3种细胞系为研究对象，加入DNA后辐照不同声强、时间或加入超声造影剂，观察各条件下的细胞基因转染率和成活率。结果 ①超声介导的基因转染与声强和辐射时间有关，最佳剂量为1w／cm^2 20s；②同样超声剂量，较高的声强较早达到最大基因转染率；③较低剂量时，微泡造影剂可使超声介导的基因转染提高2～3倍并可显著提高最高基因转染率。结论 低频超声可介导细胞基因转染，基因转染率不但与超声辐射剂量有关，而且同样剂量时，高声强较早达到最大基因转染率，最佳剂量是1w／cm^2 20s。同时，微泡造影剂可提高超声介导基因转染的最高转染率。     

Noninvasive measurement of cardiac output by continuous-wave Doppler echocardiography: initial experience and review of the literature

Doppler echocardiographic measurement of the velocity of blood flow in the ascending aorta is a noninvasive method for determining cardiac output in the critically ill patient. Fifty-four patients in the medical intensive care unit (35 men and 19 women, age range 41 to 91 years) in whom a Swan-Ganz catheter had been inserted underwent measurement of cardiac output with use of a commercially available continuous-wave Doppler echocardiographic instrument. The aortic root diameter was measured by A-mode echocardiography. An additional 26 patients (17 men and 9 women, age range 20 to 83 years) who had undergone an open-heart surgical procedure and had hemodynamic monitoring in the postoperative period also underwent Doppler measurement of cardiac output. In these patients, the aortic root diameter was measured directly intraoperatively. Cardiac output was also determined by thermodilution in both groups. An adequate A-mode study was possible in 83% of the medical patients but only 27% of the surgical patients. Doppler signals were adequate in 84% of the medical patients and 92% of the surgical patients. The correlation between thermodilution and Doppler-derived cardiac output was good in both the medical (r = 0.94, SEE = 0.78, P less than 0.001) and the surgical (r = 0.85, SEE = 0.78, P less than 0.001) group. Doppler echocardiography is a promising noninvasive method for determining cardiac output in critically ill patients.     

Ebstein's anomaly in an 85-year-old man.

This is a report of the longest survival of a patient with Ebstein's anomaly. The patient had no cardiac symptoms until the age of 79 years, when he presented with severe tricuspid incompetence and congestive heart failure, from which he ultimately died. The diagnosis was established by utilizing two-dimensional sector echocardiography.     

Restrictive left ventricular diastolic filling identifies patients with heart failure after acute myocardial infarction.

Left ventricular diastolic filling was characterized by transmitral pulsed-wave Doppler velocities in 62 patients with acute myocardial infarction, and diastolic filling variables were correlated with the presence of clinical heart failure. At the time of admission, 47 patients were free of heart failure and 15 patients were in Killip class II to IV. In the latter group of patients with heart failure, peak velocity of late filling wave caused by atrial contraction (A) was lower (0.48 versus 0.59 m/sec, p < 0.05), ratio of peak velocity of early rapid filling wave to peak velocity of late filling wave caused by atrial contraction (E/A) was higher (1.5 versus 1.1, p < 0.01), and deceleration time (136 versus 196 msec, p = 0.0001) was shorter when compared with the patients not in heart failure after acute myocardial infarction. Multivariate analysis showed that the deceleration time was a powerful independent predictor of presence of heart failure after controlling for systolic functional variables. Therefore, diastolic filling variables can complement systolic functional variables in the identification of the patients with postinfarction left ventricular failure.