芬太尼中毒死亡大白兔体内分布研究

目的建立芬太尼中毒致死的动物模型,探讨芬太尼在致死大白兔体内的分布规律。方法用6只雄性大白兔按5.4mg/kg(2LD50)经耳缘静脉推注芬太尼注射液,大白兔死后迅速解剖并提取心、肝、脾、肺、肾、脑、肌肉、睾丸、胃、心血、周围血、胆汁和尿液,用正己烷∶乙醇(20∶1)萃取,利用UPLC-MSn法检测各组织和体液中芬太尼含量,使用SPSS15.0进行方差分析,均数两两比较的SNK法进行统计分析。检验水准为α=0.05。结果实验大白兔给药后1min出现颈项强直、四肢抽搐等中毒症状,平均4.7min因呼吸抑制而死亡。死后肺内芬太尼含量最高,其次是肾和心,而尿液中含量较低。结论本实验的结果与相关案例报道基本吻合,提示肺、肾和心脏是芬太尼中毒案件鉴定的理想检材,芬太尼在致死大白兔体内的分布规律可为相关案件的鉴定提供一定的依据。     

家兔死后眼玻璃体液消光度与死亡时间关系研究

目的 为寻找一种精确推定死亡时间的方法。方法 应用 754分光光度计,在 420nm波长下,检测了 48只家兔死后不同时间的眼玻璃体液消光度,探讨其与死亡时间的关系。结果 眼玻璃体液消光度（ X）与死亡时间（ Y）呈线性正相关（ r=0.983 27, P< 0.05）,在死后 0～ 72小时,眼玻璃体液消光度与死亡时间存在回归关系（ F=116.54, P< 0.05）,直线回归方程为： Y = 453.30X＋ 0.75 [Y为死亡时间 (PMI),单位为小时; X为眼玻璃体液消光度 ]。结论眼玻璃体液消光度的测定可作为推断死后 72小时内死亡时间的参考指标之一。     

组织细胞DNA含量变化与死亡时间的相关性研究

目的研究人死后各器官组织细胞DNA降解变化规律,探讨其在推断死亡时间方面的应用价值,为推断死亡时间提供科学依据。方法已知死亡时间人尸体的心、肝、脾、肾,按死后6,12,24和48h四个时间段取材,制成石蜡切片,经Feulgen染色并图像分析;同时将各器官组织按不同时间段取材,制成单细胞悬液,应用流式细胞仪检测DNA含量。结果(1)人体各器官组织细胞经FCM检测,脾细胞核DNA随死亡时间延长呈现较好的下降梯度,而心、肝、肾,则由于自溶较快,死后6h细胞核DNA含量已很低,其变化情况与死亡时间的相关性不佳;(2)各器官组织细胞核DNA染色强度指数均随死亡时间的延长而下降。结论(1)机体死亡后,各器官组织细胞核DNA含量随死亡时间延长逐渐减少,具有一定的变化规律,其中以脾细胞核DNA含量的变化趋势与死亡时间最具相关性,肝、肾次之,而心最差;(2)方法学分析,图像分析技术(IAT)与流式细胞术(FCM)两种检测方法在研究组织细胞DNA含量变化方面,各有利弊,可互补不足。     

DNA降解与腐败尸体死亡时间的相关性

目的探讨骨髓细胞核DNA含量变化与腐败尸体死亡时间的关系。方法应用DNA高度特异性染色方法Feulgen改良法结合计算机图像分析技术对死后不同时间(0～14d)胸骨骨髓细胞核DNA含量变化进行分析。结果胸骨骨髓细胞核DNA含量随死亡时间延长呈缓慢而规律下降,直至死后两周仍未完全降解。结论死后DNA降解速率与死亡时间呈线性关系,测定死后骨髓细胞核DNA含量可望成为腐败尸体死亡时间推断的新方法。     

利用肌原纤维小片化指数推断死亡时间

目的研究死后机体骨骼肌肌原纤维小片化指数(MFI)与死亡时间之间的关系。方法双缩脲法测定室温下不同死后时间家兔骨骼肌全蛋白浓度,分光光度法测定540nm处0.5mg/mL蛋白浓度下的骨骼肌肌原纤维小片化指数。结果在死后早期,肌原纤维小片化指数随着时间延长逐步增高。结论肌原纤维小片化指数可用于早期死亡时间的推断。     

Zur ultrastruktur vitaler,postmortaler und autolysierter gerinnsel

Investigations on animal experimental and human tissue material (skin, musculature, liver) with the scanning electron microscope are reported. These studies were carried out to clarify open questions on extravascular fibrin structures after blunt and sharp traumatization of vital and postmortem nature. The network formation which was already characterized earlier as typically vital and the irregular structure of postmortem coagula could be demonstrated even with modification of the traumatization, especially in tissue hematomas. Experimental investigations on autolysis revealed an exceedingly good preservation of the structure of vital coagulum material with massive damage and granular decomposition of fibrin fiber structures produced postmortem. The structural differences in the mode of interlinking of the fibrin was shown up especially clearly by the autolysis, which suggests an application as preparation technique for the question specified.Special modifications of the preparation technique (fixation according to Karnovsky, critical-point drying) did not provide such substantial advantages for routine investigations that they might be generally recommended.Sources of artefacts and possibilities of misinterpretation of findings as well as more advanced techniques are discussed.     

The diagnostic value of postmortem blood glucose determinations in cases of diabetes mellitus

In 24 cases of death in diabetic coma the peripheral venous blood showed glucose levels exceeding 3.5 mg/ml (mean value 7.76 mg/ml). In a control material of deaths of other causes the blood glucose was usually low and often zero, and all values were well below the lower limit of the diabetic concentrations. The acetone contents of the diabetic blood varied widely and were of limited diagnostic value. We conclude that glucose concentrations above 3.5 mg/ml in the peripheral blood indicate that death occurred in diabetic coma.     

Evaluation of Virulence Factors and Antifungal Susceptibility in Yeast Isolates from Postmortem Specimens

Invasive fungal infections are a leading cause of morbidity and mortality in immunocompromised patients, especially in cases requiring a prolonged stay in the intensive care unit. A total of 99 yeast strains were isolated from 42 postmortem cases. In this study, virulence factors and antifungal susceptibility of these species were evaluated. The isolates were identified as Candida albicans (54), C. tropicalis (15), C. glabrata (12), C. parapsilosis (6), C. lipolytica (3), C. utilis (3), C. krusei (2), C. kefyr (1), and Cryptococcus neoformans (3). The most commonly isolated species was C. albicans, and no resistant species were determined. Despite the equal number of specimens, no secretion of significant virulence factors was associated with the postmortem specimen in the Candida species. Postmortem fungal investigations in forensic autopsies are useful in explaining cause of death in such cases, also may lead to protocols for the treatment of fungal infections and contribute to fungal pathogenesis and epidemiological data.     

Popliteal Vein Blood Sampling and the Postmortem Redistribution of Diazepam,Methadone, and Morphine

Postmortem redistribution (PMR) refers to the site‐ and time‐related blood drug concentration variations after death. We compared central blood (cardiac and subclavian) with peripheral blood (femoral and popliteal) concentrations of diazepam, methadone, and morphine. To our knowledge, popliteal blood has never been compared with other sites. Intracardiac blood (ICB), subclavian blood (SB), femoral blood (FB), and popliteal blood (PB) were sampled in 30 cases. To assess PMR, mean concentrations and ratios were compared. Influence of postmortem interval on mean ratios was also assessed. Results show that popliteal mean concentrations were lower than those for other sites for all three drugs, even lower than femoral blood; mean ratios suggested that the popliteal site was less subject to PMR, and estimated postmortem interval did not influence ratios except for diazepam and methadone FB/PB. In conclusion, our study is the first to explore the popliteal site and suggests that popliteal blood is less prone to postmortem redistribution.