脑络欣通对大脑中动脉阻塞再灌注模型大鼠神经干细胞增殖分化的影响

目的 观察脑络欣通对大脑中动脉阻塞再灌注（middle cerebral artery occlusion-reperfusion,MCAO-R）模型大鼠神经干细胞增殖分化的影响。方法 采用线栓法复制MCAO-R大鼠模型,将30只健康雄性SD大鼠随机分成假手术组、模型组和给药组。分别采用神经功能评分和TTC染色鉴定模型大鼠的神经功能缺损和脑缺血面积,采用免疫荧光染色法观察大鼠海马CA1、CA2、CA3、齿状回（dentate gyrus,DG）区巢蛋白（Nestin）和神经丝蛋白-H（hypophosphorylated neurofilament-H,NF-H）表达水平。结果 给药组Nestin阳性表达主要发生在DG区,NF-H阳性表达主要发生在CA3区。脑络欣通促进神经干细胞增殖的作用在DG、CA1、CA2、CA3区均十分明显,以DG区尤为突出,促进神经干细胞分化的作用主要表现在CA3、DG、CA2、CA1区。与模型组比较,给药组大鼠海马各区的Nestin、NF-H阳性细胞均明显增多,差异具有统计学意义（P＜0.05）。结论 脑络欣通具有促进海马区神经干细胞增殖并分化为神经细胞的作用。     

大鼠脑挫伤后FN表达与损伤时程关系的研究

为寻找推断脑损伤经历时间的可靠指标,采用自制自由落体撞击法致大鼠右顶叶局灶性脑挫伤模型,于不同时间段处死大鼠后,进行纤维连接蛋白的免疫组织化学及原位杂交法研究,结果发现纤维连接蛋白及其 mRNA表达水平与伤后经历时间有一定相关性,并能较好地鉴别死前脑挫伤和死后脑挫伤,可作为推断脑挫伤经历时间的参考指标之一。     

A forensic case study of a naturally mummified brain from the bushveld of South Africa

The present study reports our observations of a naturally mummified human brain found in the bushveld of South Africa. This case extends the geographic and climatic ranges in which mummified brains have been found, and it represents an additional case where no human activity has led to the mummification. The mummified brain was c. one fifth the size of a normal human brain, while the gyral and sulcal patterns of a typical human brain were clear. CT scanning of the brain revealed that subcortical structures, normally evident in this type of imaging, were not discernable, indicating a slow mummification process. Histological examination of the tissue revealed near complete degradation of the microanatomical structure, with only putative Nissl bodies remaining as identifiable neural microstructures. The specimen appears to have survived several veld fires, as well as a high annual rainfall, and a high relative humidity. It is thought that specific conditions amenable to brain mummification, but not other soft tissues, occurred in the skull of this specimen in the weeks postmortem.     

Reduction of postmortem angiography-induced tissue edema by using polyethylene glycol as a contrast agent dissolver

Postmortem investigation is increasingly supported by computed tomography (CT) and magnetic resonance imaging, in which postmortem minimal invasive angiography has become important. The newly introduced approach using an aqueous contrast agent solution provided excellent vessel visualization but was suspected to possibly cause tissue edema artifacts in histological investigations. The aim of this study was to investigate on a porcine heart model whether it is possible to influence the contrast agent distribution within the soft tissue by changing its viscosity by dissolving the contrast agent in polyethylene glycol (PEG) as a matrix medium. High-resolution CT scans after injection showed that viscosities above c. 15 mPa s (65% PEG) prevented a contrast agent distribution within the capillary bed of the left ventricular myocardium. Thereby, the precondition of edema artifacts could be reduced. Its minimal invasive application on human corpses needs to be further adapted as the flow resistance is expected to differ between different tissues.     

丰富环境对脑梗死大鼠梗死灶周围血管内皮生长因子受体的影响

目的:研究丰富环境对大鼠局灶性脑梗死后梗死灶周围血管内皮生长因子受体的影响.方法:采用开颅电凝法制作SD大鼠右侧大脑中动脉缺血(MCAO)模型,术后第24小时随机分为丰富环境(EE)组和标准环境(SE)组.以免疫组织化学法检测血管内皮生长因子受体Flt-1及Flk-1的表达.结果:大鼠大脑中动脉闭塞后,缺血区神经元变性、坏死,Flt-1和Flk-1在缺血周边区表达明显增加,经丰富环境干预后,血管内皮生长因子受体表达大量增加.结论:丰富环境可促使血管内皮生长因子受体表达上调,进而促进微血管新生,有利于脑损伤修复.     

尸体血管造影技术的发展和趋势

尸体血管造影技术是一种有效的血管检查手段,对探查尸体血管,尤其是心脏、脑部血管的情况具有重要意义。该技术起源于15世纪,发展于18、19世纪。尤其是在发现X线之后,该技术进入了快速发展阶段,无论是在对比剂、灌注方法,还是在成像方法上都取得了巨大的发展。目前,该技术已被广泛应用于实践中。但该技术仍存在一些瑕疵,首先,对比剂仍无法克服渗透弥散、栓塞血管等问题,最理想的对比剂仍未发现;其次,目前的灌注方法仍无法模拟生理血液流动状态。在＂保全尸＂的宗教和传统观念的指引下,有必要进一步提高目前的造影技术,以满足实践需求。     

Brain Fluid Content Related to Body Position and Postmortem Interval – An Animal Model

Adult male Sprague Dawley rats were euthanized and placed in a horizontal or vertical (head‐down) position at room temperature, after which brain fluid content was measured by a moisture analysis technique at variable time points. No significant difference in brain fluid content was observed between horizontal and vertical postmortem positions. A significant increase in brain fluid content was demonstrated 3, 6, and 24 h after death, with maximal fluid content observed at 24 h. Specifically, the brain fluid content of control animals was 77.79 ± 0.36%, increasing to 80.05 ± 0.22% at 24 h (p < 0.0001). This study has demonstrated no significant differences in brain fluid content related to postmortem position, suggesting that a head‐down position is not associated with increased brain fluid content or swelling. However, significant temporal increases in brain fluid content after death, most likely related to cerebral liquefaction, occur.     

大鼠脑损伤后EPO及其受体表达与损伤时间的关系

目的研究大鼠脑损伤后脑组织中促红细胞生成素(erythropoietin,EPO)及其受体(erythropoietin receptor,EPOR)的表达与损伤时间的关系。方法 72只SD大鼠随机分为对照组(36只)、脑损伤组(36只),在建模后1、2、4、8、12、24 h每组各取6只大鼠处死,取挫伤部位脑组织,应用实时荧光定量PCR和Western印迹法检测不同时间点EPO以及EPOR的mRNA表达和蛋白表达情况。结果伤后24h内,EPO及EPOR的表达随损伤时间的增加而呈上升趋势。EPO的mRNA及蛋白表达与损伤时间之间存在相关性,其相关系数分别为0.875、0.911(P0.05);EPOR的mRNA及蛋白表达与损伤时间之间存在相关性,其相关系数分别为0.936、0.905(P0.05)。结论大鼠颅脑损伤早期EPO及EPOR的表达呈逐步上升趋势,与损伤时间具有相关性,可以作为脑损伤时间推断的参考。     

急性乙醇中毒大鼠脑皮质α-syn表达与神经细胞凋亡的关系

目的观察急性乙醇中毒大鼠脑皮质α-突触核蛋白(α-synuclein,α-syn)表达及神经细胞凋亡的变化,探讨乙醇对神经细胞损害的机制。方法用50%乙醇溶液灌胃方法制作大鼠急性乙醇中毒模型。采用免疫组织化学染色技术和图像分析方法观察大鼠急性乙醇中毒后1 h、3 h、6 h、12 h脑皮质内α-syn和caspase-3的表达。测定阳性细胞数和平均光密度值,分析其变化趋势,并进行方差分析和t检验。结果急性乙醇中毒组大鼠脑皮质α-syn染色阳性细胞数和平均光密度值均呈上升趋势,6 h达到峰值,12 h略有下降,但仍高于1 h、3 h组。中毒后12 h以内,大鼠脑皮质的caspase-3阳性细胞数和平均光密度值均呈逐渐上升趋势。结论急性乙醇中毒后脑水肿、缺氧引起α-syn异常聚集可能参与乙醇中毒后早期神经细胞凋亡过程。     

加减薯蓣丸抑制单磷酸腺苷活化蛋白激酶活性对慢性脑灌注不足大鼠的神经保护研究

目的 检测慢性脑灌注不足大鼠海马组织单磷酸腺苷活化蛋白激酶（adenosine monophosphate-activated protein kinase, AMPK）水平的变化,探讨加减薯蓣丸对海马神经细胞损伤的影响及其作用机制。方法 采用改良双侧颈总动脉阻断法复制慢性脑灌注不足模型,应用尼氏染色检测神经细胞损伤情况,应用Western blot法检测海马区AMPK及p-AMPK表达水平。结果 与正常组比较,模型组大鼠海马CA1区的尼氏染色较浅,神经锥体细胞数减少,海马组织p-AMPK表达水平明显升高（P<0.05）;与模型组比较,中药组与西药组大鼠海马CA1区的尼氏染色加深,锥体细胞数量增加,p-AMPK表达水平明显下降（P<0.05）;中药组与西药组大鼠海马CA1区AMPK和p-AMPK表达水平比较,差异均无统计学意义（P>0.05）。结论 大鼠慢性脑灌注不足损伤后,AMPK过度激活,出现海马神经细胞损伤,加减薯蓣丸可抑制海马区AMPK的激活,减轻海马神经损伤。