胡椒碱及其衍生物3,4-次甲二氧桂皮酰哌啶的抗抑郁作用

目的研究胡椒碱及其衍生物3,4次甲二氧桂皮酰哌啶的抗抑郁作用,并对其作用机理进行初步探讨。方法利用小鼠强制游泳实验、悬尾实验等考察胡椒碱和3,4次甲二氧桂皮酰哌啶的抗抑郁作用,并通过测定不同脑区内单胺类神经递质质量浓度以及全脑单胺氧化酶活性变化,探讨作用机制。结果胡椒碱和3,4次甲二氧桂皮酰哌啶(10、20 mg.kg-1)长期给药后,能明显缩短小鼠在行为学实验中的不动状态时间,并且该作用随剂量增大效应逐渐降低,高剂量(80 mg.kg-1)表现出明显的中枢神经抑制作用;能显著提高脑内5羟色胺水平,而对脑内肾上腺素递质水平未见明显影响;具有较弱的单胺氧化酶抑制作用。结论胡椒碱和3,4次甲二氧桂皮酰哌啶具有较好的抗抑郁作用,其作用是通过上调中枢神经系统5羟色胺或多巴胺水平实现的。     

Relationship Between Diastolic Mitral Regurgitation and PQ Intervals or Cardiac Function in Patients Implanted with DDD Pacemakers

Diastolic mitral regurgitation (MR) is known to be induced by prolonging atrioventricular (AV) delay in patients implanted with a DDD pacemaker. We studied the relationship between diastolic MR and PQ intervals on cardiac function in 50 patients (71.3 ± 11.3 years old: mean ± SD), who had been implanted with DDD pacemakers. In 19 patients, prior to pacemaker implantation, pulmonary capillary wedge pressure (PCWP) was measured using a Swan-Ganz catheter during AV sequential pacing with an AV delay of 0.165 seconds. Transmitrai blood flow was measured with pulsed Doppler echocardiography, while prolonging AV delay stepwise by 0.025 seconds from 0.065 seconds for about 5 minutes each. In nine patients, AV delay could not be prolonged enough due to occurrence of intrinsic AV conduction. In the other 41 patients, diastolic MR was induced by prolonging AV delay. The critical PQ intervals that induced diastolic MR ranged from 0.14 to 0.26 (0.23 ± 0.03) seconds. Four of five patients whose critical PQ intervals were 0.20 seconds or shorter had heart failure, while 36 patients whose critical PQ intervals were >0.20 seconds were free from signs and symptoms of heart failure. Their PCWPs were 2–27 (7.5 ± 5.1) mmHg. There was a significant negative correlation between the critical PQ intervals for the appearance of diastolic MR and PCWP during AV sequential pacing, which was performed prior to pacemaker implantation (r = -0.85, P < 0.001). It is suggested that the appearance of diastolic MR is determined mainly by PQ intervals and cardiac function. Measurement of the critical PQ intervals that induce diastolic MR may be useful in assessing cardiac function in patients implanted with DDD pacemakers.     

Electroporation in a Model of Cardiac Defibrillation

INTRODUCTION: It is known that high-strength shock disrupts the lipid matrix of the myocardial cell membrane and forms reversible aqueous pores across the membrane. This process is known as "electroporation." However, it remains unclear whether electroporation contributes to the mechanism of ventricular defibrillation. The aim of this computer simulation study was to examine the possible role of electroporation in the success of defibrillation shock. METHODS AND RESULTS: Using a modified Luo-Rudy-1 model, we simulated two-dimensional myocardial tissue with a homogeneous bidomain nature and unequal anisotropy ratios. Spiral waves were induced by the S1-S2 method. Next, monophasic defibrillation shocks were delivered externally via two line electrodes. For nonelectroporating tissue, termination of ongoing fibrillation succeeded; however, new spiral waves were initiated, even with high-strength shock (24 V/cm). For electroporating tissue, high-strength shock (24 V/cm) was sufficient to extinguish ongoing fibrillation and did not initiate any new spiral waves. Weak shock (16 to 20 V/cm) also extinguished ongoing fibrillation; however, in contrast to the high-strength shock, new spiral waves were initiated. Success in defibrillation depended on the occurrence of electroporation-mediated anodal-break excitation from the physical anode and the virtual anode. Some excitation wavefronts following electrical shock used a deexcited area with recovered excitability as a pass-through point; therefore, electroporation-mediated anodal-break excitation is necessary to block out the pass-through point, resulting in successful defibrillation. CONCLUSION: The electroporation-mediated anodal-break excitation mechanism may play an important role in electrical defibrillation.     

胰十二指肠切除术在高龄患者中的应用(英文)

目的评估胰十二指肠切除术在75岁以上高龄患者中应用的指征和结果。方法回顾性分析72例在2002-01～2006-12进行胰十二指肠切除术患者的临床资料,将其中18例75岁及以上的高龄患者与54例小于75岁的患者的术前、术中、术后的临床资料和病理结果等情况进行归纳、对比分析。结果两组患者在性别、术前合并症、术中出血量、手术时间、术后并发症、死亡率、ICU留观时间和住院时间等方面无统计学差异;高龄组患者中没有输入新鲜冷冻血浆,而非高龄组患者术中平均输入(1.33±2.54)单位新鲜冷冻血浆(P<0.001);高龄组没有发生术后出血的并发症,两组腹腔内感染率均为4%;高龄组患者再次开腹手术率为0%,而非高龄组为6%(P>0.05),两组均未出现死亡病例。高龄组胆管癌所占比例明显高于非高龄组(55.6%vs 25.9%,P=0.021)。结论 75岁以上高龄患者和小于75岁的患者一样能够耐受胰十二指肠切除术,并能从中获益;高龄的壶腹周围肿瘤患者中,胆管癌的发病率最高,提示在对高龄人群进行体检或疾病筛查时,要高度重视对胆道系统的详细检查。     

程为平教授额顶区倒丁字丛刺法治疗强哭强笑症举隅

强哭强笑是中风后遗症中情志障碍的主要表现之一,给病人及其家属带来极大痛苦。临床上有报道表明抗抑郁药和多巴胺能药物可以改善症状,但没有指定治疗药物。越来越多的患者开始寻求针灸治疗。程为平教授从事临床多年,在使用额顶区倒丁字丛刺法治疗中风后强哭和强笑症上积累了丰富的临床经验。