实验大鼠胃Kappa-阿片受体与死亡时间的相关性

目的研究实验大鼠餐后死亡不同时间段的胃主细胞Kappa-阿片受体(KOR)的表达变化。探讨其变化、表达规律与死亡时间(PMI)的相关性。方法实验雄性大鼠,随机分为对照组和实验组,进食后断颈处死后于不同时间提取组织检材,对组织进行免疫组织化学染色,采用图像分析软件测定阳性面积、积分光密度、平均光密度、平均灰度等参数,用SPSS统计软件对各参数与死亡时间的关系进行相关性分析。结果死后9d内的胃主细胞上Kappa-阿片受体随着死亡时间(PMI)的延长,其积分光密度和阳性面积与死亡时间(PMI)存在一定的相关回归关系。结论实验大鼠死后胃主细胞上Kappa-阿片受体的变化规律与死亡时间有相关性。     

Petechial Hemorrhages and Ethanol in Deaths from Intoxication

Petechiae in conjunctivae and in the palpebrae/skin of the eyelids are of particular interest for the forensic pathologist, because of their association with pressure on the neck. They have been described in the eyelids of intoxicated persons both in case reports and in text books of forensic pathology. We studied 590 deaths caused by intoxication, and 75 had petechiae either in the conjunctivae, the eyelids, or in both locations. We examined the influence of drugs and ethanol on the location of the petechial hemorrhages in these deaths. Deaths with ethanol in blood and in urine/vitreous humor more often had petechiae in both locations than those without. This association was statistically significant, independent of body position and livor mortis. No association between the location of petechiae, medicinal drugs, or narcotics was found. These results suggest that ethanol may contribute to the development of petechial hemorrhages in deaths from intoxication.     

Detection of Diatoms by a Combination of Membrane Filtration and Transparentness,

Diagnosis of drowning remains a difficult issue in current forensic sciences. A large number of diatoms were lost by removing the supernatant after centrifugation in the conventional forensic diatom test. We developed a novel membrane filtration method to enrich diatoms from samples. A new solution using different ratios of acetic acid and eugenol is prepared to make the membrane transparent. These processes allow the diatom‐containing membrane to be visualized and identified easily by light microscopy. The tissues contaminated by water rich in diatoms were detected by the new method for the recovery of diatoms. Eleven drowning cases were analyzed by both the new method and the conventional method to compare the sensitivity of both methods. The recovery of the novel diatom test method was 54.2 ± 23.1%. The positive rate of the novel method has been proven to be superior to the conventional method in the diagnosis of drowning.     

Why We Need Postmortem Analysis of Cardiac Implantable Electronic Devices

The prevalence of cardiac implantable electronic devices (CIEDs), pacemakers and implantable cardioverter defibrillators (ICDs) is increasing. However, postmortem analysis of CIEDs is not performed routinely. Fourteen consecutive CIEDs were analyzed. The indication for and date of implantation, technical data, CIED reprogramming, heart rhythm disturbances, patient demographics and medical consultations were investigated. Death during the first year after implantation was seen in 54%, whereof 71% consulted a physician within 10 days before death. The time of death was attributed to a particular day in 29%. There was a relationship between CIEDs and cause/manner of death in 50%. Although limited by a small sample size, this study advocates the routine postmortem CIED analysis for forensic and clinical purposes in selected cases. Patients with CIEDs seem to show an increased risk of death during the first year after implantation. The analysis of CIEDs can be helpful in evaluating the time/cause/manner of death.     

致命室性快速心律失常心室肌能量的代谢改变与氧化损伤

目的探讨致命室性快速型心律失常(LVTA)能量代谢相关变化及氧化损伤。方法建立以乌头碱(ACO)注射和冠脉结扎(CAL)心肌缺血诱导的LVTA-心脏性猝死(SCD)SD大鼠模型,以过度麻醉(PI)及冠脉结扎心衰致死(CAL-B)为各自对照,检测心室肌线粒体膜电位(MMP)、活性氧(ROS)、丙二醛(MDA)、磷酸肌酸(PCr)及血清肌钙蛋白I(cTnI)含量,并进行比较。结果成功制备ACO-LVTA及CAL-LVTA大鼠14只及6只。与各自的同行对照比较,ACO-LVTA组及CAL-LVTA组心室肌的ROS及MDA呈升高的趋势,PCr呈下降的趋势,其中CAL-LTVA的MDA显著高于其同行对照(P0.05)。ACO-LVTA组心室肌的MMP低于对照组,但高于CAL处理的两组。CAL-LVTA组血清cTnI高于对照组,且显著高于ACO-LVTA组及其对照与处理前(P0.01),ACO-LVTA组血清cTnI高于对照组与处理前。心肌ROS水平与VT及VF持续时间相关(P0.05),相关系数分别为0.44、0.46。结论发生LVTA后,心室肌MMP及PCr下降、ROS、MDA升高,血清cTnI升高,表明LVTA可导致能量代谢改变及氧化损伤,可能与线粒体功能异常相关。     

大鼠早期缺血心肌中Basigin mRNA的表达

目的检测Basigin mRNA在大鼠早期缺血心肌和非缺血区心肌中的表达差异及探讨其法医学意义。方法建立大鼠早期心肌缺血手术模型,分为EIM组、NIM组、假手术组以及空白对照组,采用real-time PCR方法检测大鼠心肌缺血后15min、30min、1h和2h Basigin mRNA的表达量。结果与NIM组、假手术组及空白组相比,EIM组BSG mRNA表达量在缺血15min时降低,而冠状动脉结扎1h后表达量降低到SO组的一半,此时具有统计学差异(P0.05),结扎2h后表达量恢复至SO组水平。NIM组、SO组和空白对照组之间表达量无统计学差异(P0.05)。结论心肌急性缺血2小时内BSG mRNA表达降低明显,之后升高,说明BSG参与早期缺血心肌自我保护病理生理过程,提示BSG可用于鉴定早期心肌缺血。     

溺死鉴定中硅藻检验的应用

在法医学检案中,溺死诊断以及入水地点的判定一直是重点和难点之一,硅藻检验被认为是一种相对可靠的诊断溺死的方法,而根据硅藻的群落特征推断其入水区域具有一定的可信度。对不同水域内硅藻进行研究,可为溺死鉴定及入水区域的判定提供参考。本文就硅藻相关的生物学特性、检验方法等相关的国内外研究进展进行综述,供法医学工作者在相关科研和检案实践中参考。     

液化石油气中毒死亡兔的法医病理学研究

目的观察新西兰兔在液化石油气中毒后不同组织的病理学特征,探讨其在日常法医鉴定工作中的应用价值。方法健康新西兰兔42只,随机分为3组:轻度中毒组6只,中毒死亡组30只,窒息死亡组6只。在中毒和致死过程中进行行为学观察,分析心血中液化石油气浓度,中毒死亡组和窒息死亡组进行大体解剖形态学和组织病理切片观察及心血检验。结果轻度中毒组在吸入少量液化石油气后会表现为呼吸加快、站立、伸舌、磨牙等兴奋的状态;中毒死亡组尸体解剖主要表现皮肤、肌肉呈土黄色,气管、支气管出血明显,肺气肿明显;中毒死亡组心血中可检验出液化石油气成分。结论新西兰兔液化石油气中毒的特征主要表现为皮肤、肌肉呈土黄色,气管、支气管出血明显,心血可检出液化石油气成分。我们推断液化石油气的神经毒性与缺氧可能是液化石油气中毒死亡的机制。     

GFAP和VEGF在创伤性脑损伤中表达的研究进展

创伤性脑损伤是世界上导致死亡及残疾的主要原因之一。检测对中枢神经系统损伤有高度特异性和敏感性的生物标志物,可以在一定程度上反映损伤情况。胶质纤维酸性蛋白与血管内皮生长因子均可作为颅脑损伤的生物学标记物,其表达变化规律、峰值出现时间,与创伤性脑损伤的严重程度及损伤时间的推断密切相关,对于法医病理学具有重大意义。该文对胶质纤维酸性蛋白与血管内皮生长因子的分子生物学特性及其在创伤性脑损伤中的表达进行综述。     

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。