Skin and soft tissue artifacts due to postmortem damage caused by rodents.

Five cases of postmortem bite-injuries inflicted by rodents are presented (five males between 41 and 89 years; three cases caused by mice, one case by rats, one case of possible mixed rodent activity by rats and mice). The study presents a spectrum of phenomenological aspects of postmortem artifacts due to rodent activity to fresh skin and soft tissue: the majority of the injuries have a circular appearance. The wound margins are finely serrated with irregular edges and circumscribed 1-2 mm intervals within, partly showing protruding indentations up to 5 mm. Distinct parallel cutaneous lacerations deriving from the biting action of the upper and lower pairs of the rodents incisors are diagnostic for tooth marks of rodent origin but cannot always be found. No claw-induced damage can be found in the skin beyond the wound margins. Areas involved in the present study were: exposed and unprotected parts of the body, such as eyelids, nose and mouth (representing moist parts of the face); and the back of the hands. Postmortem rodent activity may occasionally be expected on clothed and therefore protected parts of the body. The phenomenon of postmortem rodent activity to human bodies can be found indoors especially under circumstances of low socioeconomic settings; outdoors this finding is particularly observed among fatalities among homeless people.     

Experimental forensic and bioanthropological aspects of soft tissue taphonomy: 1. Factors influencing postmortem tissue desiccation rate.

Euthanized rats' carcasses were exposed in an environmental chamber to multiple variables including: (1) position, (2) enveloping clothing, and (3) soil interment in an effort to determine the individual variables' effect on postmortem rate of body and visceral organ water loss. Results indicated that body water loss was enhanced by a horizontal position versus vertical, probably because of wider spread of bacteria- and enzyme-laden abdominal fluid secondary to diaphragm digestion with consequent greater tissue digestion and liquefaction. Clothing also accelerated the desiccation rate. Desiccation was about equally as effective by soil interment as by air exposure, though simulating windy conditions by tripling the air flow rate resulted in much more rapid desiccation in the air-exposed specimen. These studies suggest that the single most important factor influencing postmortem body water loss rate is the environment at the skin surface that acts to enhance or impair water removal from the skin surface and thus influences the water concentration gradient between the skin and underlying deeper tissues.     

Determination of opiates in postmortem bone and bone marrow.

Bone and bone marrow of a fatally poisoned heroin addict were analyzed by FPIA and GC-FID, immediately after death. A piece of the bone from the above case was buried for 1 year and analyzed by the same procedure. Morphine was detected in all specimens at concentrations of 195, 340 and 155 ng/g for bone marrow, bone and buried bone, respectively. A loss of 54.4% of morphine concentration was observed during 1-year burial. Such findings have potential forensic value in cases of skeletonized remains.     

介绍一种简便的骨软组织处理方法

过去所使用的骨软组织处理法,如石灰法、煮沸法,均耗时较长而污染较重,且难以将骨上附着的软组织全部处理干净.笔者于1997年在瑞士研修期间,向瑞士同行学习了一种骨软组织处理法,现介绍如下.     

Death due to superficial soft tissue injuries.

A series of deaths due to multiple superficial injuries is reported. These cases represented 5% of a consecutive homicide series in the Northern Territory of Australia. All cases were characterized by extensive superficial injuries, particularly involving soft tissue, which were present over much of the body including the face, head, arms, legs, and trunk. Upper-limb fractures were present in some cases, as were fractured ribs. The internal organs and tissues were pale, but there was either little or no organ damage. No significant volume of free blood was found in any of the body cavities. In one case, fat emboli were identified in moderate numbers in the lung and kidney. Death due to multiple superficial soft tissue injuries has not previously been characterized in the literature.     

脑组织与法医学死亡时间推断

目前，通过脑组织推断死亡时间已经成为法医学领域研究的新热点，大量研究资料表明：死亡时间与脑组织细胞DNA、RNA、ATP含量及脑温度、脑组织血管内皮生长因子等变化有高度相关性。脑CT、MRI、磁共振波谱等检查手段对死亡时间的推断也有帮助。本文对国内外相关文献进行综述，以期为相关研究提供参考。     

Light microscopical investigations on structural changes of skeletal muscle as artifacts after postmortem stimulation

Samples of skeletal muscle were taken from 20 human corpses where mechanical or electrical stimulation had been carried out up to 8h postmortem (hpm) in order to estimate the time since death. The stimulation had caused an idiomuscular bulge or tetanic contraction of the muscle tissue at this location. The muscle samples were examined for structural changes of the fibers by light microscopy. A comparison with control muscle samples taken contralaterally from the same corpse, showed that the findings previously interpreted as being of intravital origin, e.g. destruction of fiber integrity, invagination and contraction bands, could also be due to postmortem alterations. It is hypothesized that structural changes to the muscle fibers can, in general, be produced as long as the manifestation time is shorter than the supravital phase after the time of force impact.     

离体人胸骨骨髓DNA降解与腐败尸体死亡时间推断的初步研究

目的研究死后胸骨骨髓DNA的降解与较长死后间隔时间(PMI)的关系。方法采用改良Feulgen染色及计算机图像分析技术对离体人胸骨(取材后分别室温搁置0,1,3,5,7d)骨髓DNA含量进行定量检测。结果在较长PMI范围内,人胸骨骨髓DNA含量仍呈现下降规律。结论人胸骨骨髓DNA降解规律可望应用于较长PMI的推断。     

The effects of corrosive substances on human bone, teeth, hair, nails, and soft tissue

Abstract: This research investigates the effects of household chemicals on human tissues. Five different human tissues (bone, tooth, hair, fingernails, and skin/muscle/fat) were immersed into six different corrosive agents. These agents consisted of hydrochloric acid, sulfuric acid, lye, bleach, organic septic cleaner, and Coca‐Cola^® soda. Tap water was used as a control. Tissue samples were cut to consistent sizes and submerged in the corrosive liquids. Over time, the appearance, consistency, and weight were documented. Hydrochloric acid was the most destructive agent in this study, consuming most tissues within 24 h. Sulfuric acid was the second most destructive agent in this study. Bleach, lye, and cola had no structural effects on the hard tissues of the body, but did alter the appearance or integrity of the hair, nails, or flesh in some way. The organic septic cleaner and tap water had no effect on any of the human tissue tested during the timeframe of the study.     

RNA指标在死后人体皮肤组织中稳定性研究

目的探讨多种RNA指标的表达水平在死后人体皮肤组织中的稳定性。方法收集死亡时间(PMI)明确的人体皮肤组织样本10例,提取总RNA,运用实时荧光定量PCR(qRT-PCR)技术检测ACTB、GAPDH、18S、miR-203、5S、1et-7a、RPS29、U6共计8个RNA指标的表达水平。geNorm软件评估各RNA指标表达水平的稳定性,挑选出稳定的内参指标并分析其表达水平与相关因素(年龄、性别、死因)的关系。结果人体皮肤组织中5S、U6和miR-203表达水平最为稳定,其平均表达量与年龄、性别、及死因无关(P0.05)。结论 5S、U6和miR-203可以作为qRT-PCR方法研究PMI的理想内参指标。     

死后离体人肝组织的激光共聚焦显微拉曼光谱分析

目的观察和探讨人死后肝组织细胞激光共聚焦显微拉曼光谱的变化规律及其与死亡时间的关系。方法离体肝组织于死后48～72h内每隔4h提取样品,采用激光共聚焦显微拉曼光谱技术进行检测。观察800cm-1～3 200cm-1范围内检测样本特征峰的变化,指认其对应的化学基团,选择强度比值I1094/I2923作为响应值,并进行统计学计算。结果在48～72h内,随时间的延长,肝组织细胞主要散射峰峰位无明显变化,而其峰强度有明显差异;与核酸有关的峰（1 094cm-1）强度随时间推移有明显下降;与脂类有关的峰（1 454cm-1、2 923cm-1）强度变化不明显;各相对峰强（I1094/I2923）随死亡时间的推移而减小,并得到回归方程（r=0.914）。结论人死后肝组织细胞DNA降解随死亡时间延长呈下降趋势,I1094/I2923值与PMI呈负线性关系。激光共聚焦显微拉曼光谱技术有望成为推断死亡时间的检测方法。     

Distribution of digoxin, digitoxin and their cardioactive metabolites in human heart and kidney tissue. A postmortem study

A method was developed for the specific determination of digoxin and digitoxin, as well as their semisynthetic derivatives and dependent cardioactive metabolites, in autopsy samples of heart and kidney. A collective of six patients on long-term treatment with therapeutic doses of beta-acetyldigoxin had a mean myocardial digoxin content of 46.1 +/- 25.0 ng/g (SD); kidney: 50.3 +/- 30.3 ng/g. Digoxigenin bisdigitoxoside represented the second most important metabolite in heart and kidney; digoxigenin monodigitoxoside and digoxigenin follow, respectively. In a collective of seven patients on maintenance treatment with digitoxin, the mean tissue levels were higher but the metabolic pattern was similar (myocardial digitoxin content: 78.9 +/- 38.4 ng/g, renal content: 104.1 +/- 44.1 ng/g). The amount of digoxin formed by hydroxylation under long-term treatment with digitoxin in heart and kidney were approximately 10 ng/g. A case of digoxin intoxication differed both in the tissue content and in the metabolic distribution.     

Application of ultrasonography to postmortem examination. Diagnosis of pericardial tamponade

In postmortem examination, it is difficult to diagnose pericardial tamponade in a dead body from the findings of conventional external examination alone. However, ultrasonography is a common diagnostic tool for pericardial tamponade in clinical practice. We studied the postmortem diagnosis of pericardial tamponade at external examination level by applying an ultrasonographic device. The ultrasonographic findings were compared with the conventional autopsy findings. Among 455 cases of forensic autopsy in Hamburg and Tokyo conducted within 5 days after death, we successfully diagnosed 11 cases of pericardial tamponade by ultrasound imaging prior to autopsy, and failed to diagnose pericardial tamponade in only two cases. In addition, 79 cases of external examination conducted at the Tokyo Medicinal Examiner's Office were also examined with ultrasonography, and we diagnosed three cases of pericardial tamponade and five cases of pericardial effusion. The differences in ultrasonographic findings between tamponade and effusion were relatively clear. Although autopsy provides definitive evidence for the cause of death, sometimes autopsy cannot be performed due to some social factors. In such cases, conventional external examination alone cannot establish a cause of death by pericardial tamponade, and application of diagnostic imaging technique will be helpful. While CT and/or MRI may provide more detailed information than ultrasound imaging, these techniques require special equipment, room and specialist, and most of all involves high cost, which is perhaps the most important consideration in the present atmosphere of medical cost containment. On the other hand, the ultrasonographic devices we use are compact, and can be used directly at the scene of death. Postmortem application of ultrasonography may be a valuable adjunct in the work of medical examiners and forensic pathologists.     

Correlation of antemortem and postmortem digoxin levels.

Postmortem serum digoxin levels from any source routinely exceed antemortem values. Variation resulting from site of sampling gave a mean postmortem to antemortem ratio of 1.96 for heart, 1.63 for subclavian vein, and 1.42 for femoral vein samples. No correlation could be made between the postmortem interval and the increase in post-mortem serum values, irrespective of the site of sampling. A combination of femoral venous serum and vitreous humor values gave the best information for determining possible antemortem digoxin toxicity.     

Determination of morphine in postmortem rabbit bone marrow and comparison with blood morphine concentrations

The aim of this study is to predict how long after time of death a buried body could be analyzed for opiates in soft tissues and to show the accessibility and suitability of bone marrow as a useful toxicological specimen from buried bodies. Morphine solutions were injected in nine albino rabbits. Doses ranged from 0.3 to 1.1 mg/kg with 0.1 mg/kg increments. One hour after the injections, the rabbits were sacrificed. Blood, urine and bone marrow samples were collected for analysis. After the whole bodies were buried, femur bone marrow specimens were collected on the seventh and fourteenth days. CEDIA was used to monitor morphine contents of the collected samples. All experimental cases showed that the increase in the given morphine doses correlated with the increase in blood and bone marrow morphine concentrations. High morphine concentrations were detected in urine samples, but there was no correlation between the urine and blood or urine and bone marrow morphine concentrations. Statistically meaningful increases in bone marrow morphine concentrations were found parallel to increase of blood morphine concentrations. Seventh and fourteenth day postmortem morphine concentrations also followed this correlation. Morphine concentrations in bone marrow at 7 and 14 day postmortem decreased consistently when compared with bone marrow morphine concentrations collected immediately after death. We conclude that in sudden death when other specimens are unavailable due to degradation, bone marrow can be a most useful specimen. Further experimental research in this area is required to validate bone marrow as an alternative tissue.     

组织中三甲胺-氮浓度变化与晚期PMI关系初探

目的探索死后尸体组织中三甲胺-氮(TMA-N)浓度变化规律及其与晚期死亡时间的关系。方法健康SD大鼠66只,颈椎脱臼法处死,随机分成11组,分别于死后即刻、1、2、3、4、5、6、7、8、9、10d取大鼠肌肉、肝脏和肾脏组织,用分光光度法检测TMA-N浓度,所得数据用方差分析比较组间差异性,并进行回归方程拟合。结果3种组织中TMA-N含量随死后时间延长而增加,肌肉于死后7d、肝脏和肾脏于死后8d达到高峰,之后有所下降,并均于死后10d再次升高,肝、肾组织之间TMA-N含量比较无统计学差异性。死后2~7d内,PM I与肌肉TMA-N浓度变化拟合度最高(R2=0.969);死后3~8d内,与肝肾中TMA-N浓度变化拟合度最高(R2=0.953)。结论死后组织中TMA-N含量变化与PM I有相关性,可望为晚期PM I推断提供参考,但肌肉与肝肾TMA-N含量变化规律存在一定差异,需选择最适时段以提高PM I推断的准确性。