Localization and quantification of the nonspecific esterase in injured skin for timing of wounds.

Histochemical quantification of the nonspecific esterase (NSE) in injured skin was performed using histochemical demonstration of the enzyme and a microspectrophotometric scanning technique on specimens taken from 32 Hartley guinea-pigs and 8 cases of human skin wounds. In all antemortem incisions and lacerations, including those made at the agonal stage, NSE activity could be observed in the dermal tissue of the wound edge. The enzyme activity increases with the antemortem duration of the injuries. Both total content and mean concentration of NSE in the wound edge between antemortem and postmortem wound groups differ significantly (less than 0.01). Multiple range test shows that significant differences (P less than 0.05 or P less than 0.01) of total content of NSE in the wound edge also exist in 0-5 min, 15-30 min, 1-h, 2-h and 4-h antemortem incised wound groups and in 0-min, 5-min, 15-30 min, 1-h and 4-h antemortem laceration groups. The positive NSE reactions in 8 cases of human skin wounds were similar. The study indicates that histochemical quantification of NSE in injured skin is very useful in timing wounds and is exactly applicable in medicolegal practice. According to the different influences of inhibitors on enzymes, it was inferred that the enzyme activity in wound edges was due to B-esterase.     

Complement component C3a or C3a desArg as a new marker for estimation of local vital reactions in incised skin wounds.

The anaphylatoxin C3a or its desArg form (C3a/desArg) generated during complement activation could be detected in the vicinity of incised skin wounds of guinea pigs using immunoblotting methods. The C3a/desArg peptides were detectable immediately after injury in local sites up to 3 mm from the wound edge. In subsequent determinations of up to at least 3-day-old antemortem wounds, the maximum concentration of these peptides was largely localized up to 6 mm from the wound edge at 2 h after injury. In postmortem wounds, however, these peptides were undetectable. When they were released in antemortem wounded tissues they could be detected up to 1 day at 22 degrees C after death. These results suggest that the detection of C3a/desArg in wounds using immunoblotting methods can be useful for distinguishing ante- from postmortem wounds.     

枪弹创纤维蛋白形成能力的免疫组化研究

采用免疫组化PAP染色法，对57例人体枪弹创标本的纤维蛋白形成能力进行检测。结果发现，所有生前枪弹创均有纤维蛋白形成祖创缘邻近皮肤组织内毛细血管内皮细胞以及血管内充盈的红细胞膜上亦呈棕色阳性染色；死后30min内形成的枪弹创均有纤维蛋白形成；死后37min后形成的枪弹创无纤维蛋白形成，说明死后30min，纤维蛋白形成能力仍存在。作者认为，仅根据损伤局部有纤维蛋白形成即判断为生前伤是不恰当的，尚应结合损伤部位、损伤程度、损伤类型以及其它生活反应综合评定，不宜单凭纤维蛋白判断。     

大鼠皮肤切创后E-选择素表达及稳定性研究

目的探讨大鼠皮肤切创后E-选择素表达规律及法医学意义。方法健康SD大鼠90只,随机分成4组：正常对照组、活体切创组（30min～7d12个时间点）、死后切创组（30min～3h3个时间点）、死后稳定性组（-20％6h-7d9个时间点,25％6h～3d5个时间点）。在大鼠头部建立皮肤切创模型,按设定的时间点取皮肤检材,运用免疫组化和图像分析技术,检测血管内皮E-选择素的表达规律。结果在活体切创组中,伤后1hE-选择素在血管内皮细胞内即呈阳性表达,持续至伤后7d,且随时间变化呈规律性表达。在正常对照及死后切创组未见阳性表达。死后-20％稳定性组各时间点E-选择素表达与死后即刻比较无显著性差异（P〉0．05）。25％各时间点与死后即刻比较有显著性差异（P〈0．01）。结论E-选择素在创伤后血管内皮细胞内特异性的表达具有时序性规律,且低温条件下稳定性较好。     

对纤维蛋白诊断生前伤的评价——45例枪弹创组织的MSB染色和扫描电镜对比观察

生活反应是诊断生前伤的主要根据.近二十年来,法医病理学在研究生前伤和死后伤的诊断中,采用了多种新兴技术,如扫描电镜技术、酶组织化学技术、酶标技术、电泳技术等,促使生前伤的诊断水平有明显提高.伤后存活1小时死亡者,大部分皆可获得明确诊断;立即死亡或在濒死期形成的损伤,由于生活反应甚微,或受腐败等     

Quantitation of nucleotides,nucleosides and bases in antemortem and postmortem bloodstains by high-performance liquid chromatography

Ante- and post-mortem bloodstains prepared from the blood of volunteers and corpses were analysed for ATP and its related compounds by reversed-phase high-performance liquid chromatography (HPLC). The results showed that (1) ATP was present in a large amount in antemortem bloodstains but not in postmortem stains, (2) AMP, adenosine, inosine, hypoxanthine, xanthine and uracil either were not detected or were detected in smaller amounts in antemortem than in postmortem bloodstains, and (3) ADP was present in both ante- and postmortem bloodstains. These differences suggest that quantitation of these compounds may be useful in identifying whether bloodstains are ante- or post-mortem.     

死后肌肉切创创壁纤维蛋白的扫描电镜观察

用扫描电镜观察大鼠肌肉组织切创创壁纤维蛋白网的形成和形态,发现生前和死后8小时内的切创壁,均有纤维蛋白网形成,两者形态无显著差异。死后16小时,切创创壁无纤维蛋白网形成。     

Acute Benztropine Intoxication and Fatality

A woman was found unresponsive with an empty bottle of Cogentin^® prescribed to another. Admitted to an area hospital, her condition steadily declined until death 29 h after admission. Following toxicological screening on hospital (admission) whole blood, the only significant compound detected was benztropine. Benztropine was confirmed at 0.28 mg/L – the highest antemortem blood concentration recorded in a case of toxicity or fatality uniquely associated with benztropine. A second serum antemortem specimen showed a benztropine concentration of 0.19 mg/L. Despite over 24 h in the hospital, benztropine was also found in the postmortem specimens collected at autopsy. Peripheral blood, central blood, liver, and gastric concentrations were 0.47 mg/L, 0.36 mg/L, 9.6 mg/kg, and 44 mg, respectively. These results indicate that benztropine exhibited a potential difference between whole‐blood and serum (plasma) concentrations. Additionally, in consideration of literature data, benztropine was found indicative of a compound prone to at least some postmortem redistribution.     

扫描电子显微镜下生前和死后枪弹创的对比观察

本文用扫描电镜,对11例生前枪弹创和12例死后不同时间形成的枪弹创作对比观察。结果发现,生前枪弹创有大量红细胞和血小板凝块,纤维蛋白网形成,死后10min内的枪弹创亦有少许散在红细胞和纤维蛋白形成,很少见纤维蛋白网。死后25min的标本仍可见稀疏的红细胞,但无纤维蛋白形成。作者认为在扫描电镜下诊断生前枪弹创,需全面观察,综合分析。     

The extent of postmortem drug redistribution in a rat model.

The aim of this study was to investigate the postmortem redistribution of several drugs in a rat model and to examine if any of the pharmacological properties was related to the extent of this phenomenon. One of the following drugs: phenobarbital (phenobarbitone), acetaminophen (paracetamol), carbamazepine, codeine, verapamil, amphetamine, mianserin, trimeprazine (alimemazine) or chloroquine was administered together with nortriptyline orally to rats 90 min prior to sacrifice. Heart blood was sampled immediately before sacrifice and after 2 h postmortem, as it has previously been shown that this is sufficient time for postmortem concentration changes to occur in heart blood. Blood was also sampled from the clamped abdominal inferior vena cava (representing peripheral blood) and tissue samples were taken from lungs, myocardium, liver, kidney, thigh muscle, forebrain, and vitreous humor together with a specimen from the minced carcass. Drugs were analyzed by high performance liquid or gas chromatography. For phenobarbital, acetaminophen and carbamazepine the postmortem to antemortem blood drug concentration ratios were close to 1.0 and tissue concentrations were low. The postmortem to antemortem heart blood drug concentration ratio for chloroquine (6.9 +/- 1.5) was higher than for nortriptyline (3.5 +/- 0.3), and the remaining drugs (codeine, verapamil, amphetamine, mianserin, and trimeprazine) showed ratios of the same magnitude as nortriptyline. The postmortem to antemortem blood drug concentration ratios for both heart blood and blood from the vena cava and also the lung to antemortem blood drug concentration ratio were closely related to the apparent volume of distribution for the drugs studied (p < 0.001). Accordingly, an apparent volume of distribution of more than 3-4 L/kg is a good predictor that a drug is liable to undergo postmortem redistribution with significant increments in blood levels. The postmortem drug concentration in blood from vena cava was closely related to the antemortem blood level, confirming that among the postmortem samples, the peripheral blood sample was the most representative for the antemortem blood concentration.     

家兔死后体表锐器伤出血现象的研究

目的对家兔死后体表锐器损伤出血现象进行研究,以期能够贴近实际办案需要,找到一个更为实用的鉴别生前锐器伤和死后锐器伤的方法。方法家兔脱毛,制作锐器损伤模型,采用大体观察结合HE染色镜下组织病理学观察。结果死后锐器损伤出血量均较少,随着时间延长出血量减少,出血速度慢。死后30min的锐器损伤在形成过程与生前损伤有所区别,但在死后12h肉眼观察结果与生前损伤难以区别。死后1h以上的锐器损伤与生前损伤不同之处在于创缘不会被血染。结论位于尸体低下位置的死后30min内的锐器创与生前锐器创的区别是出血量相对较少。死后60min-90min的锐器伤出血量少,创缘皮肤不被血染,肌肉的出血较局限,与生前损伤相鉴别较容易。     

Localization and quantification of histamine in injured skin as parameters for the timing of wounds.

Localization and estimation of the histamine (HA) content in skin wound edges in 86 Sprague-Dawley rats and three cases of human injuries were carried out by a microfluorimetric method specific for this amine which forms a complex with o-phthalaldehyde (OPT). Distribution and density of the mast cells in the same areas were observed at the same time by toluidine blue stain. In all skin specimens with antemortem wounds, both the epidermis and upper dermis exhibit extracellular yellowish fluorescence of the HA-OPT complex. The fluorescent zone spreads in the wound edges with the lapse of time in vital injuries. The HA content increases gradually up to 30 min and then the yellow histamine fluorescence in areas 0-200 microns from the wound edge decreases. None of these features can be observed in normal skin and postmortem-injured skin. Mast cell degranulation can be demonstrated in all antemortem-injured skin. No statistical relationship exists between the number of mast cells and the HA-OPT fluorescence in either ante- or postmortem-injured groups. This study indicates that skin HA microfluorimetry by the OPT method is of practical value for distinguishing ante- from the postmortem wounds and for timing antemortem wounds.     

To Test or Not To Test?: The Value of Toxicology in a Delayed Overdose Death

A case demonstrating the necessity of thorough death investigation processes where toxicology plays an active role is presented. A 33‐year‐old white man presented to the emergency room in respiratory distress after an overdose episode where he was revived on the scene by fire rescue. His condition continued to deteriorate and he expired 6 days after the initial incident. No admission specimens were available for testing; however, there were specimens drawn 4 and 5 days after the incident. Drug paraphernalia from the scene was obtained by the laboratory through collaboration with local law enforcement. Drug paraphernalia was initially tested in the laboratory and after obtaining the results, the antemortem and postmortem specimens were tested identifying mitragynine and U‐47700, among other drugs. These results indicate the value in obtaining and testing drug paraphernalia, and the value of testing antemortem specimens even in the event of a delay.     

Assessment of the Role Played by N‐propanol Found in Postmortem Blood in the Discrimination Between Antemortem Consumption and Postmortem Formation of Ethanol Using Rats

This study disproves the reliability of n‐propanol as a biomarker to establish whether the ethanol found in postmortem blood is derived from antemortem ingestion or postmortem putrefactive processes. Two groups of rats were given ethanol or normal saline solution, respectively, and sacrificed 1.5 h later. After putrefaction, blood and, in a few cases, urine samples from the rats were analyzed for ethanol and n‐propanol by head‐space gas chromatography equipped with flame ionization detection. Although the concentration ratios of ethanol/n‐propanol in the postmortem blood collected from the bodies without prior alcohol consumption were expected to be <20 (as per limited case reports and previous in vitro studies), in samples from several rats that were on saline solution, this ratio was found to exceed 20. In conclusion, the concentration ratio of ethanol/n‐propanol in postmortem blood does not allow for the discernment between antemortem ingestion and the postmortem synthesis of ethanol.     

损伤皮肤酯酶显微定位、定量与损伤时间推断

作者用显微分光光度计扫描法,对32只 Hartly 豚鼠的实验性损伤以及8例人体损伤的皮肤组织中的酯酶,进行定位、定量研究。发现生前损伤后,创壁0.4mm 以内真皮胶原纤维等间质即刻出现酯酶着色,存活时间越长,着色就越深、范围越大。生前各时间组互相间有显著差异。所有的生前损伤组创缘酯酶含量及平均单位面积酶含量与正常皮肤及死后损伤组差别均极显著。人体损伤皮肤组织酯酶定位及含量变化与豚鼠所见一致。因此,作者认为损伤皮肤酯酶定位定量分析以推断损伤后存活时间,已可应用于法医实际案例鉴定中。作者还根据对抑制剂的反应认为创缘真皮胶原纤维上所显示的酯酶为 B-酯酶。     

Proximal End Root Morphology Characteristics in Antemortem Anagen Head Hairs

The proximal end morphology of antemortem anagen head hair was compared with the characteristics documented to occur in postmortem hairs. Antemortem anagen and telogen head hairs (N = 967) were recovered following exposure to seven environments. Root morphology characteristics consistent with those reported in postmortem hairs were observed in 66 (14%) hairs exposed to a water, normal saline, outdoor soil, or indoor shower environment. Thirty‐three anagen hairs (7%) exhibited a root band at the proximal end. The mean distance from the root tip to the onset of the root band ranged from 0.23 to 0.7 mm, depending on the environment. The mean distance from the root tip to the onset of the root band was 0.46 mm, with a mean band length of 0.44 mm. The results illustrate the need to better characterize postmortem banding through quantitative measurements, including the range for root tip to band distance and the overall band length.     

Crack Propagation in Teeth: A Comparison of Perimortem and Postmortem Behavior of Dental Materials and Cracks*

Abstract: This study presents a new method for understanding postmortem heat-induced crack propagation patterns in teeth. The results demonstrate that patterns of postmortem heat-induced crack propagation differ from perimortem and antemortem trauma-induced crack propagation patterns. Dental material of the postmortem tooth undergoes dehydration leading to a shrinking and more brittle dentin material and a weaker dentin-enamel junction. Dentin intertubule tensile stresses are amplified by the presence of the pulp cavity, and initiates crack propagation from the internal dentin, through the dentin-enamel junction and lastly the enamel. In contrast, in vivo perimortem and antemortem trauma-induced crack propagation initiates cracking from the external surface of the enamel toward the dentin-enamel junction where the majority of the energy of the crack is dissipated, eliminating the crack’s progress into the dentin. These unique patterns of crack propagation can be used to differentiate postmortem taphonomy-induced damage from antemortem and perimortem trauma in teeth.     

兔皮肤钝器伤IL-1β、COX-2和MCP-1 mRNA表达与法医学应用

目的应用荧光定量PCR技术检测兔皮肤钝器伤后IL-1β、COX-2和MCP-1mRNA的时序性表达规律,分析其与损伤时间的关系。方法分别在兔耳皮肤钝器伤后<0.5h,0.5h,1h,2h,3h,4h,5h,6h,8h,12h,24h,1d,3d,7d和死后10min,0.5h,1h取材,一步法提取组织总RNA,逆转录合成cDNA第一条链,荧光定量PCR检测IL-1β、COX-2和MCP-1mRNA逆转录合成第一条cDNA链的拷贝数,作统计学分析。结果IL-1βmRNA在钝器伤后<0.5h表达显著增强(P<0.001),0.5h达到峰值,至第2d降至基本水平;COX-2mRNA于创伤后0.5h表达显著增强(P<0.05)并持续强表达至24h开始下降,第2d降至正常;MCP-1 mRNA在钝器伤后于1h表达显著增强(P<0.05),于3h出现表达峰,至第3d降至正常;3个指标在死后各时间组与正常对照无明显表达差异。结论检测皮肤IL-1β、COX-2和MCP-1mRNA可对早期损伤时间的推断提供帮助,并且这三个指标都可以鉴别生前伤和死后伤。     

Toxicological findings in military aircraft fatalities from 1986-1990.

Toxicological findings in all military aircraft fatalities investigated by the Division of Forensic Toxicology at the Armed Forces Institute of Pathology from 1986-1990 are presented. Carbon monoxide saturation levels greater than 10% were found in 4% of the 535 cases where appropriate specimens were collected. Positive ethanol findings were more indicative of postmortem formation than antemortem consumption. In only 1 case were abused drugs (cannabinoids in a passenger) detected. Other drugs identified included nicotine, chloroquine and over-the-counter analgesic agents, antihistamines and sympathomimetic drugs.     

Investigation of cardiac troponins in postmortem subjects: comparing antemortem and postmortem levels

The limitations of autopsy in the diagnosis of death due to ischemic heart disease are well known. In the living, a simple reliable biochemical assay for cardiac troponins is used in the diagnosis of acute myocardial ischemia. Several studies have investigated the use of biochemical assays for cardiac troponins in postmortem subjects as a means to distinguish between a cardiac and anoncardiac cause of death. All of these studies, however, rely upon assigning subjects to "cardiac" or "noncardiac" death on the basis of a postmortem examination. As postmortem examination does not always accurately distinguish between these two groups, this approach is intrinsically flawed.Our study compares antemortem and postmortem cardiac troponin levels in five subjects. The antemortem samples were retrieved from the hospital biochemistry laboratory after each subject's death. The postmortem samples for each subject were taken from different sites and at different times during the early postmortem period.Erratic results bearing little or no relation to the antemortem cardiac troponin level were obtained for all subjects. Four of the five subjects had raised antemortem troponin levels, although only one had a cardiac cause of death.From this, we conclude that postmortem blood is not a suitable substrate for standard biochemical assays of cardiac troponins, which are designed for use on serum taken from living patients. In addition, the results of our study support the view that elevated cardiac troponins are a marker of serious morbidity and are not specific for cardiac injury as the primary cause of morbidity or mortality.