大鼠骨骼肌挫伤愈合过程中caspase-3的表达及时间规律

目的观察大鼠骨骼肌挫伤愈合过程中,caspase-3的表达及其变化规律。方法制作大鼠右小腿骨骼肌挫伤模型,应用免疫组织化学法、Western blot法及caspase-3活性测定法对不同时间段大鼠骨骼肌挫伤后caspase-3表达进行检测。结果免疫组织化学及Western blot均显示,挫伤周边区caspase-3的活性随时间延长逐渐升高,5d时达最高峰,随后活性逐渐下降。免疫组织化学染色结果显示,伤后3～5d挫伤处坏死的骨骼肌细胞被清除干净,新形成的肌细胞大量增生,且新形成的肌细胞胞浆内有caspase-3表达;损伤后7～14d,新形成的肌细胞内仍然有caspase-3的阳性表达。结论大鼠骨骼肌挫伤后,挫伤周边骨骼肌表达caspase-3有一定的时间规律性,可望作为推断骨骼肌挫伤时间的指标之一;大鼠骨骼肌挫伤后,新形成的肌细胞表达caspase-3,提示caspase-3可能在骨骼肌分化过程中起重要作用。     

Cocaine‐Induced Intracerebral Hemorrhage in a Patient with Cerebral Amyloid Angiopathy*

Abstract: Intracerebral hemorrhage (ICH) is a well‐recognized complication of recreational cocaine use. The precise mechanism of the cocaine‐induced hemorrhagic event is unclear, although multiple factors have been implicated. We report a case of a 62‐year‐old woman who suffered left parieto‐occipital ICH with herniation and death, following a cocaine binge. Microscopic examination also revealed extensive cerebral amyloid angiopathy (CAA) in the vicinity of the hemorrhage. We additionally studied brain tissue in eight subjects between ages of 60 and 80 who were positive for cocaine metabolites at autopsy; of these, none had vascular amyloid‐β deposits by immunohistochemistry. Whereas we found no evidence that chronic cocaine use is a risk factor for CAA, given the age‐associated nature of CAA and the aging population using cocaine, CAA‐induced hemorrhage in the setting of cocaine use may be more common than recognized. This is the first reported case of CAA‐associated ICH precipitated by cocaine.     

豚鼠脑震荡实验模型的建立和形态观察

实验用健康豚鼠46只,予以编号。用暴力撞击头部,建立脑震荡的动物模型。30只动物出现昏迷,于数分钟內恢复正常,无感觉和运动后遗症。分别于3、6、12、24、48、72h,1、2、3、4周处死。肉眼观察脑表面无异常,光镜和电镜下,72h以内各组胼胝休和脑干传出传入纤维轴索肿胀成串珠状或断裂成节段形,髓鞘崩解。其中24、48h有数量不等的巨噬细胞浸润;银染色可见轴索断端有收缩球。大脑皮质神经细胞部分有缺血固缩或肿胀变性,尼氏体溶解及卫星现象。血管反应及胶质细胞增生,偶见结节。伤后1～4周反应逐渐减轻。其余16只动物有不同部位的脑组织挫伤。对照组7只动物无上述阳性发现。     

多发性软组织挫伤后对肺及其他脏器的影响

目的观察多发性软组织挫伤后短时间内死亡案例的脏器病理学改变。方法应用常规组织学及免疫组织化学染色技术进行光学显微镜检查。结果光镜检查见肺组织毛细血管扩张充血，白细胞集聚，肺组织散在片状出血、灶状坏死及透明膜形成；心脏间质血管扩张充血，点灶状纤维溶解；脑组织充血水肿，肝脾充血。免疫组化发现肺泡腔及部分血管内纤维蛋白染色阳性，部分脾脏血管内及肾髓质集合管中肌红蛋白染色阳性。结论本研究结果提示多发性软组织挫伤后短时间内死亡的死因为成人呼吸窘迫综合征（ARDS）合并多脏器功能衰竭。     

凋亡相关基因表达与早期脑损伤时间关系研究

目的 探讨脑挫伤早期细胞凋亡相关基因Bcl-2、Fas表达的变化规律与损伤时间关系。方法 运用光镜观察脑挫伤后脑组织的形态学变化,同时应用图像分析技术检测脑挫伤早期不同时程Bcl-2、Fas免疫组化染色平均光度值的变化规律。结果 伤后8h在脑挫伤周围可见典型的凋亡神经细胞;伤后30min损伤灶周围神经细胞出现Bcl-2、Fas阳性表达,以后呈逐渐上升趋势且表达范围亦逐渐扩大,其中Bcl-2蛋白表达在伤后4h达高峰,随后呈下降的趋势,至伤后10～12h其表达程度与伤后1h相比无明显差异。结论检测细胞凋亡相关基因的表达可用于早期脑损伤时间的推断及生前与死后脑损伤的鉴别。     

吗啡依赖鼠成瘾相关脑区腺苷酸环化酶的变化

目的观察吗啡依赖鼠成瘾相关脑区腺苷酸环化酶的变化,探讨成瘾相关脑区腺苷酸环化酶的变化与吗啡依赖机制的关系。方法建立吗啡依赖大鼠模型,应用酶组织化学的方法对吗啡依赖鼠七个相关脑区腺苷酸环化酶的变化进行观察,用图像分析系统测定其灰度值,并进行统计学处理。结果吗啡依赖组脑区腺苷酸环化酶含量升高。结论吗啡成瘾相关七个脑区腺苷酸环化酶含量随吗啡依赖时限的延长有增加的趋势,结果提示吗啡依赖机制与特定脑区腺苷酸环化酶的含量变化有密切关系。进一步揭示AC/cAMP-PKA系统上调与吗啡成瘾机制的关系。     

Globus Pallidus Necrosis Unrelated to Carbon Monoxide Poisoning: Retrospective Analysis of 27 Cases of Basal Ganglia Necrosis

Bilateral globus pallidus necrosis is said to be characteristic of carbon monoxide (CO) poisoning. However, there has been no scientific test of this hypothesis. To examine the assertion that globus pallidus necrosis is typical of CO poisoning, this study examined autopsy cases from the King County Medical Examiner's Office (KCMEO) between 1994 and 2013. Twenty-seven cases with bilateral basal ganglia lesions were identified and examined for associated or causative disease or injury with the following results: 10 cases of drug overdose, seven heart disease, three asphyxia, two chronic ethanolism, two Huntington-like disorder, and one case each of remote trauma, rheumatic heart disease, and cerebral artery gas embolism. Additionally, review of all known cases at KCMEO of CO poisoning found no evidence of globus pallidus or basal ganglia necrosis. Thus, this study provides no support for the assertion that globus pallidus necrosis is characteristic of CO poisoning.     

Fatal Penetrating Injuries Sustained by High-pressure Water Jet Unit

The high-pressure water jet unit is a generator of frequent burst of water jets. The water jet reaches very high speeds and is able to cause wounds similar to those of high-velocity projectiles. In the presented case, unusual fatal injuries sustained by water jet are presented. Operating with the unit, an untrained worker accidentally activated a high-pressure water jet unit, and the extremely high pressure of water liberated the jet unit from his hand and whirled it around him. A jet stream of water ran across his body and caused fatal penetrating injuries in the femoral region. The edges of the wound were mainly sharp with contusion rings on the skin beyond the edges. Exploring the inside of the canals during the autopsy, the left femoral artery and vein were found to be completely transected. The resemblance to a firearm entry wound and the severity of the internal injury make it a noteworthy entity.     

Sudden Unexpected Deaths Due to Intracranial Meningioma: Presentation of Six Fatal Cases,Review of the Literature,and A Discussion of the Mechanisms of Death

Deaths due to meningiomas are routinely diagnosed in clinical practice because this neoplasm tends to present with the typical progression of neurological deficits. On the other hand, sudden unexpected deaths due to meningiomas are rarely described in the literature. The study presents six fatal cases of previously undiagnosed intracranial meningiomas from the Cook County Medical Examiner's Office from 1998 to 2014. The most common explanation of the mechanism of sudden death due to intracranial neoplasms is a rapid increase in intracranial pressure produced by the mass effect of the neoplasm. Other mechanisms of death include acute intracranial and intratumoral hemorrhage, and benign neoplasms that grow in the vicinity of vital centers altering neural discharge in autonomic pathways leading to cardiac suppression or lethal arrhythmia. Forensic pathologists must keep in mind that sudden unexpected death caused by intracranial meningiomas, although extremely rare, may be encountered in the forensic setting.     

益气养阴活血法对糖尿病合并脑缺血大鼠海马脑源性神经营养因子表达及空间学习记忆的影响

目的 观察益气养阴活血法对糖尿病合并脑缺血大鼠空间学习记忆能力及脑源性神经营养因子（brain derived neurotrophic factor, BDNF）表达的影响,并运用工具药（BDNF的Trk受体抑制剂）证实BDNF通路在其中的作用。方法 将大鼠分为假手术组、模型对照组（糖尿病合并脑缺血伴气阴两虚、瘀血阻络证）、益气养阴活血组、益气养阴活血+K252a组、益气活血组,每组20只,选用具有益气养阴活血作用的人参、川芎、玉竹、黄精组合,运用免疫组织化学法和Morris水迷宫实验观察益气养阴活血药对糖尿病合并脑缺血模型大鼠空间学习记忆的作用及对BDNF表达的影响。结果 与模型对照组比较,益气养阴活血药物和益气活血药物均可以明显增加糖尿病合并脑缺血大鼠海马齿状回BDNF的表达（P<0.01）,益气养阴活血药物显著缩短模型大鼠找到水下平台的潜伏期（P<0.01）,益气养阴活血药物和益气活血药物均显著延长大鼠在原水下平台的停留时间（P<0.05,或P<0.01）,其中益气养阴活血药物效果优于益气活血药物（P<0.05）。侧脑室注射K252a可以阻断益气养阴活血药物促进模型大鼠的空间记忆能力的恢复（P<0.01）。结论 益气养阴活血药物可能通过促进模型大鼠海马齿状回BDNF的表达而改善空间记忆功能。