溺死大鼠肺组织AQP-1、AQP-4的表达

目的观测生前溺死与死后抛入河水中大鼠肺组织水通道蛋白-1(aquaporin-1,AQP-1)、AQP-4的表达变化。方法将30只健康雄性Wistar大鼠随机分为河水溺死组、抛尸入水组及脱颈致死组。HE染色观察各组大鼠肺组织形态学变化,实时荧光定量PCR法检测各组大鼠肺组织AQP-1、AQP-4 m RNA的表达,免疫组织化学、Western印迹法检测其蛋白表达。结果免疫组织化学法和Western印迹法检测河水溺死组AQP-1蛋白的表达高于抛尸入水组和脱颈致死组(P0.05)。免疫组织化学法显示河水溺死组AQP-4蛋白的表达高于抛尸入水组和脱颈致死组(P0.05),而Western印迹法未检测出三者的差别(P0.05)。河水溺死组大鼠肺组织的AQP-1、AQP-4 m RNA表达高于抛尸入水组(P0.05)。结论河水溺死组的大鼠在急性肺损伤时肺组织AQP-1、AQP-4 mRNA及蛋白表达增高可能对生前溺死与死后抛尸的鉴别有一定意义。     

大鼠挫伤肺组织中水通道蛋白1表达变化

目的探讨水通道蛋白1（aquaproin 1,AQP1）在大鼠挫伤肺组织中的表达变化及其与肺水肿的关系。方法将SD大鼠随机分为实验组和对照组,制备肺挫伤模型,用免疫组织化学方法检测肺组织中AQP1的分布和表达变化。结果肺挫伤后1和3h肺组织出现水肿、出血,炎性细胞浸润,5h炎性反应进一步加重。AQP1表达在挫伤后1、3和5h均明显高于对照组（P〈0．01）,随着伤后时间延长,水肿加重,AQP1持续上升。正常AQP1主要分布在支气管和肺泡壁的毛细血管内皮细胞及间质细胞,挫伤后肺AQP1的表达部位未发生改变,但积分光密度值（intergrated optical density,IOD）差异有统计学意义（P〈0．01）。结论挫伤肺组织可能存在AQPs的基因表达调控失衡,导致大量水的异常跨膜转运以及在肺组织中的异常聚集,这可能是挫伤肺组织水肿形成原因之一。     

大鼠溺死后肺组织与血清IL-1β、IL-13mRNA表达变化

目的检测大鼠肺组织和血清中IL-1β、1L-13mRNA表达变化,探讨IL-1β、IL-13mRNA的变化情况与溺死的关系。方法 12只SD大鼠随机分为对照组、溺死组(实验组)。分别提取各组大鼠右侧肺下叶及右心室血清,应用TaqMan探针法检测肺组织及右心室血清IL-1β、IL-13mRNA的表达情况。结果 (1)溺死组大鼠肉眼观察:体表征象及解剖所见符合生前溺死特征。(2)肺组织中IL-1β、IL-13mRNA表达检测:与对照组比较,实验组IL-1β、IL-13表达呈下降趋势,差异无统计学意义(p0.05)。(3)血清中IL-1β、IL-13mRNA表达检测:与对照组比较,实验组IL-1β表达显著升高(p0.01)、IL-13表达显著升高(p0.01)。结论 (1)IL-1β、IL-13 mRNA在溺死组肺组织中表达呈下降趋势,可能是大鼠溺死出现代偿性抗炎反应综合症导致免疫无能的表现。(2)IL-1β、IL-13 mRNA在血清中表达明显升高,可能与溺水应激及溺死后急性肺损伤创伤应激有关。     

淡水溺死大鼠肺组织与血清中IL-1α、IL-1β和IL-13mRNA表达

目的检测溺死大鼠肺组织和血清中白细胞介素(interleukin,IL)-1α、IL-1β、IL-13 m RNA的变化,探讨其在法医学溺死诊断鉴定中的潜在价值。方法 18只SD大鼠随机分为溺死组、空白对照组和心肌梗死组(对照)。分别收集各组大鼠右心室血清及右肺下叶、心肌,应用Taq Man探针法检测肺组织及右心室血清IL-1α、IL-1β、IL-13 m RNA的表达情况。结果与空白对照组及心肌梗死组比较,溺死组大鼠肺组织IL-1α、IL-1β及IL-13 m RNA表达差异均无统计学意义(P0.05),右心室血清IL-1β、IL-13 m RNA表达升高(P0.05)。空白对照组与心肌梗死组比较,血清中IL-1α、IL-1β及IL-13 m RNA表达差异均无统计学意义(P0.05)。结论细胞因子IL-1β及IL-13 m RNA在溺死后大鼠右心室血清中表达量均有改变,表明其变化与溺死密切相关。     

SEM/EDAX检测内脏异物元素成分诊断溺死

为探讨溺死诊断的依据和推断入水地点，用扫描电镜／X－射线谱仪（SEM／EDAX）检测19例溺死尸体及28只溺死兔的肺、肾、心、肝等组织异物颗粒及其元素成分和含量，并以陆地上死亡尸体14具及8只陆地上勒死兔（2只勒死后入水浸泡6天）作实验对照。结果发现，19例溺死尸体及28只溺死兔的肺边缘区呼吸性细支气管、肺泡管、肺泡囊及肺泡内均可见高能谱值的异物颗粒，其大小自数微米至数十微米不等，多为无定形异物颗粒或细小异物颗粒集落。其中元素成分为硅、铝、钙、铁、铬、钛、钼、铅、锡、铜、溴等，与入水地点溺液中所含元素成分相同；肾、心、肝组织异物颗粒检出率分别为77％、53％及47％，数量较少，颗粒较小，大小自1微米以下至十数微米。非溺死尸体及实验兔的肺、肾、心、肝组织未检出或偶尔检出异物颗粒，其元素成分多为铁、钙或硅等，可能是病理及生理性异物颗粒，如含铁血黄素、钙化灶等。用SEM／EDAX检测水中尸体组织中异物颗粒及其元素成分和含量，可以诊断溺死，推断入水区域，为明确案件性质和确定侦察范围提供科学依据。     

MD-VF-Auto SEM法与浮游生物基因复合扩增体系在溺死诊断中的应用比较

目的 比较微波消解-真空抽滤-自动扫描电子显微镜（microwave digestion-vacuum filtrationautomated scanning electron microscopy,MD-VF-Auto SEM）法与浮游生物基因复合扩增体系在溺死诊断50例溺死案例的肺、肝、肾组织进行检测分析,比较两种方法在各组织中的阳性检出率。结果 溺死案例使用MD-VF-Auto SEM法检验的硅藻阳性率为100%,在6例非溺死案例的肝、肾组织中检出少量硅藻。浮游生物基因复合扩增体系的阳性率为84%,非溺死案例的肺、肝、肾组织结果均为阴性。两种方法检测结果相比,肝、肾组织的阳性率和总阳性率差异均具有统计学意义（P<0.05）,而肺组织阳性率差异无统计学意义检出硅藻外的其他浮游生物。两种方法相结合,可为溺死诊断提供更可靠的依据。     

趋化因子CCL2、CCL7和CCR2在淡水溺死后大鼠肺组织及血清中的表达

目的应用Taqman探针法检测淡水溺死后大鼠肺组织和血清中CCL2、CCL7以及CCR2 mRNA的表达水平,从而探讨其在法医学实践中,是否能为溺死的诊断提供辅助的科学依据。方法 24只健康雄性SD大鼠随机分为实验组(淡水溺死组)、对照组(空白对照组、淡水应激组及疾病对照组)。对各组大鼠尸表及内部脏器进行肉眼观察并取部分左心室心肌和右下叶肺组织行HE染色;提取大鼠右心室血清及右下叶肺组织,采用Taqman探针法检测CCL2、CCL7和CCR2 mRNA的表达水平。结果 (1)淡水溺死组大鼠解剖征象及肺组织HE染色结果符合溺死的特征,疾病对照组大鼠心肌组织HE染色结果符合心肌梗死的病理改变;(2)各组大鼠肺组织中CCL2、CCL7和CCR2mRNA的表达水平:淡水溺死组CCL2和CCL7 mRNA的表达水平显著高于空白对照组及淡水应激组(P0.05),且淡水溺死组CCR2 mRNA表达水平高于淡水应激组(P0.05);与疾病对照组比较,无统计学差异(P0.05)。(3)各组大鼠血清中CCL2、CCL7和CCR2 mRNA表达水平:淡水溺死组血清中CCL2、CCL7和CCR2 mRNA的表达水平均高于对照组水平(P0.05)。结论采用Taqman探针法检测肺组织及血清中CCL2、CCL7和CCR2 mRNA的表达水平,对溺死的诊断有一定的辅助作用。     

肺组织硅藻定量分析在实验动物溺死诊断中的应用

目的探讨肺组织硅藻检验在法医学溺死诊断中的应用价值。方法将实验动物随机分为溺死组、死后入水组和陆地死亡组,采用微波消解-真空抽滤-扫描电镜联用的硅藻检验方法对肺组织和溺液硅藻进行定量分析,记录肺组织与溺液硅藻含量的比值(ratio of content of diatoms in lung tissue and drowning fluid,C_L/C_D)。结果溺死组实验兔的C_L/C_D值(5.82±3.50)高于死后入水组(0.47±0.35);溺死组实验猪肺叶不同部位的C_L/C_D值均高于死后入水组;在海水、咸淡水交界、河道淡水及湖泊淡水中,溺死组实验猪的C_L/C_D值均高于死后入水组(P0.05)。动物实验中,C_L/C_D值1.6的案例均来自溺死组。结论 C_L/C_D值是溺死诊断中有较好应用前景的指标。     

检测浮游生物叶绿素相关基因诊断溺死的实验研究

目的评估浮游生物叶绿素相关基因检测用于溺死诊断的价值。方法将18只大白兔随机分为溺死组（n=10）、死后抛尸组（n=6）和对照组（n=2）,各组分别取心血及肺、肝、肾、脑组织,分离浮游生物并提取其DNA,用PCR技术检测叶绿素相关基因EG（EG1和EG2）及SK（SK1和SK2）。同时用硝酸消化法检验肺和肝组织中的硅藻。结果溺死组心血及肺、肝、肾、脑组织中EG1分别检出9、10、9、7和8例阳性,EG2分别检出8、10、7、5和7例阳性;死后抛尸组仅在心血和肺组织中各检出1例EG1阳性;对照组各组织均未检出EG1和EG2。SK1、SK2除在溺死组心血、肺和肾有少数检出外（≤2例）,在其他组未检出扩增产物。硝酸消化法从溺死组肺、肝组织中分别有9例及3例检出硅藻,死后抛尸组仅在1例肺组织中检出。结论浮游生物叶绿素相关基因EG用于溺死诊断的阳性检出率要高于硝酸消化法,在溺死诊断中具有较高的应用价值。     

气单胞菌aerA和hlyA两基因在溺死诊断中的应用

目的建立溺死尸体脏器气单胞菌气溶素(aerA)和溶血素(hlyA)两基因的PCR-CE检测方法,验证该方法的特异性和灵敏度,并探讨其在溺死诊断中的应用价值。方法设计气单胞菌(Aeromonas)特异性引物aer-A1和hlyA-1,构建PCR-CE方法;扩增52种标准株DNA;确定最低DNA检测浓度;检测16只实验猪和40例真实案件尸体组织样本,分别计算两对引物总阳性率。结果引物aerA-1可特异性扩增杀鲑气单胞菌和温和气单胞菌,产物片段为180bp,灵敏度分别为0.034、0.92ng;引物hlyA-1可特异性扩增杀鲑气单胞菌和嗜水气单胞菌,产物片段为150bp,灵敏度分别为0.94、0.034ng。利用aerA-1检测溺死实验猪和真实案件尸体组织样本,溺死阳性率分别为70.00%、78.38%;利用hlyA-1检测溺死实验猪和真实案件尸体组织样本,溺死阳性率分别为80.00%、83.78%。结论基于气单胞菌aerA基因和hlyA基因建立的PCR-CE检测方法进行溺死诊断,快速灵敏,特异性好,有良好的应用前景。     

创伤性脑损伤大鼠水通道蛋白4表达变化及法医学意义

目的观察大鼠颅脑损伤后不同时间内水通道蛋白4（AQP4）mRNA表达的变化，探讨AQP4在脑损伤经过时间推断中的意义。方法利用液压冲击法制作不同程度大鼠颅脑损伤模型，在伤后不同时间（0．5、2、6、12、24、48、72h），应用RT-PCR法检测脑组织AQP4 mRNA表达，同时以非损伤组做对照。结果不同程度颅脑损伤后0．5h脑组织AQP4 mRNA表达均开始上调（P〈0．01），6、12h依次增高，24h达到高峰，差异均有统计学意义（P〈0．01），72h时仍维持较高水平（P〈0．01）；0．5h时轻度、中度、重度脑损伤时AQP4 mRNA的表达差异两两之间无统计学意义（P〉0．05），2、6、12、24、48、72h轻度、中度、重度脑损伤时AQP4 mRNA的表达差异两两之间有统计学意义（P〈0．01）。结论颅脑损伤后AQP4 mRNA呈现出时序性变化，其变化规律可望成为法医学推断早期脑损伤时间的指标之一。     

Molecular Pathology of Pulmonary Edema in Forensic Autopsy Cases with Special Regard to Fatal Methamphetamine Intoxication

Pulmonary edema is a common finding in fatal methamphetamine intoxication. However, the underlying mechanism remains poorly understood. This study investigated the molecular pathology of alveolar damage involving pulmonary edema in forensic autopsy cases. Seven candidate reference genes (RPL13A, YWHAZ, GUSB, SDHA, GAPDH, B2M, and ACTB) were evaluated in the lung by the geNorm module in qBase^plus software. RPL13A, YWHAZ, and GUSB were identified as the most stable reference genes. Using these validated reference genes, intrapulmonary mRNA expressions of matrix metalloproteinases (MMPs), intercellular adhesion molecule‐1 (ICAM‐1), claudin‐5 (CLDN‐5), and aquaporins (AQPs) were examined. Relative mRNA quantification using TaqMan real‐time PCR assay demonstrated higher expressions of all markers except for AQP‐5 in fatal METH intoxication cases. These findings suggested alveolar damage and compensatory response in fatal METH intoxication cases. Systematic analysis of gene expressions using real‐time qPCR is a useful tool in forensic death investigation.     

Improved method for the detection of TATP after explosion

TATP in post explosion exhibits was reported earlier to be best recovered from vapor phase. A typical procedure includes its adsorption on Amberlite XAD-7, elution with acetonitrile and analysis by GC/MS. In this work, improved recovery of TATP from the vapor phase was achieved by SPME using PDMS/DVB fiber and immediate sampling to GC/MS. The recovery of TATP by SPME was compared with headspace and with adsorption on Amberlite XAD-7 by spiking onto filter paper put in a 100 mL beaker. The limit of detection of TATP was 6.4 ng in these conditions, few orders magnitude more than in the other tested methods. Recovery of TATP in the presence of various solvents was also studied. Acetone, water, and mixtures of water:alcohols (1:1) were found to reduce the recovery of TATP. Using SPME, TATP has been identified in dozens of post-explosion cases.     

A transition zone phenomenon of the skin in cadavers lying in bath water

In three cases a phenomenon is reported, seen on the skin of bodies found dead after a longer time of lying in bathtubs filled with water. The sign was parallel to the surface of the water and showed a breadth up to about 1 cm. Contrary to the surrounding skin, the mark was characterized by paleness and clearly les distinct formation of postmortem alterations as put-refaction. Searching for an explanation, temperature measurements were performed in model. The results showed the marginal paleness of the skin to be a thermal phase transition phenomenon. This mark has a forensic message too: it demonstrates a longer remaining of the corpse in the corresponding position, is a statement concerning the high of the water level, and allows a reconstruction of the original situation after manipulation, but is no sign of vital reaction.     

我国中水回用的立法现状及思考

我国虽早就开始推广中水回用,但是各地中水回用的普及和推广效果却一直不佳。究其原因,中水回用法律制度未能起到很好地引导和保障作用是重要原因。我国在上世纪90年代就开始了中水回用的立法工作,但是,中水回用法律制度中还存在着不少问题。要想普及和推广中水回用,就必须要建立和完善中水回用法律制度,只有在法律的引导和保障之下,中水回用才能真正健康发展。     

Medical evaluation of the victims of the 1986 Lake Nyos disaster

A cloud of carbon dioxide gas, with an estimated volume of 1 km3 was released from Lake Nyos, a volcanic crater lake in Cameroon, Africa, causing 1700 to 2000 human fatalities as well as killing thousands of livestock and wild animals. At the request of the Cameroonian Government, the Office of Foreign Disaster Assistance of the U.S. Department of State sent a multidisciplinary team which included 2 forensic pathologists to assist the Government of Cameroon in investigating this natural disaster. The medical evaluation was concentrated in 3 areas: the autopsy of human and animal fatalities, examination and interview of survivors, and examination of the scene of the disaster. Toxicologic specimens were obtained at autopsy, and numerous samples of lake water were collected. The autopsy findings were consistent with asphyxia. The results of chemical analyses excluded many volatiles but not carbon dioxide as the toxic agent. The exact source of this gas continues to be a subject of a heated geologic debate, but fermentation of organic materials in the lake water has been eliminated on the basis of C14 isotope studies. This investigation underlines the value of forensic pathologists in epidemiological studies and in the examination of living persons.     

Articles found in the possession of a methamphetamine abuser

A plastic syringe containing bloody fluid, 2 ampules of 20% glucose, an ampule containing diphenhydramine hydrochloride and calcium bromide, powder in a plastic bag and powder wrapped in paper were among the articles found in the possession of a 42-year-old male methamphetamine abuser, who had been taken to a mental hospital owing to his hallucinations.Examination of the patient revealed several recent needle punctures on the left forearm. The concentration of methamphetamine and its metabolite, amphetamine, in blood collected 1 day following the last intake was 76 nmol/100 g. Analysis of the powder and of the contents of the syringe revealed methamphetamine hydrochloride at a concentration of 99.0–99.5% and 7.4%, respectively. Neither glucose nor diphenhydramine were detected in the contents of the syringe.It would seem that the patient abused methamphetamine hydrochloride by intravenous injection after dissolving it in city water or distilled water.     

Sex determination of cadaver material by the detection of specific nucleotide sequences of the Y chromosome following DNA cleavage

A gene technological method of sex determination in cadaverous material is reported. The samples were taken from a child's corpse, which was nearly completely skeletonized after 1 year in water. From cells of the bone marrow the DNA was isolated and digested by restriction enzymes. A defined fragment of 2.12kb length was cleaved off by the endonuclease HaeIII in the presence of Y chromosomes. After agarose-gel electrophoresis of the DNA fragments, the specific sequence was detected by hybridization with the cloned, radioactively labelled complementary plasmide pHY2.1.     

Death by peroral ingestion of soluble glass (sodium silicate)

The intake of 0.51 of water glass (sodium metasilicate; colloid pH 12.5) led to death within 1-1.5 h. Autopsy revealed alkali burns of the stomach mucosa. The stomach contained a small amount of liquid with a pH of 11.5. Histologically, numerous bronchioles and alveoles were filled with amorphous material. This material was chemically proved to be condensed water glass. The obstruction of large parts of the lungs by water glass led to an inhibition of alveolar gas diffusion, which may have been the cause of death. The transformation of the water glass from liquid to solid occurred in the lungs by means of the carbonic acid of expiration air. This was made possible because the pH of water glass had been changed by gastric secretions from 12.5 to 11.5. Water glass starts to solidify around pH 11.4-11.3.