Grading rigor mortis with myotonometry--a new possibility to estimate time of death.

Myotonometry has been applied to grade rigor mortis. The myotonometer is a hand-held instrument which gives a mechanical impact against the muscle. The muscle responds with a damped vibration which is registered and treated mathematically. The period and the logarithmic decrement of decay of the vibrations were found to change with the development of rigor mortis. The method gives quantitative information on the muscular stiffness and it can be used when estimating the time of death.     

脑组织中ATP含量变化与死亡时间关系的初步研究

本文报道用生物发光法测定不同死亡时间狗脑组织中ATP含量的变化．结果表明：随着死亡时间的延长，脑组织中ATP浓度逐渐下降，这对法医在实际检案工作中推断死亡时间有一定的应用价值。     

Evaluation of age estimation technique: testing traits of the acetabulum to estimate age at death in adult males

This study evaluates the accuracy and precision of a skeletal age estimation method, using the acetabulum of 100 male ossa coxae from the Grant Collection (GRO) at the University of Toronto, Canada. Age at death was obtained using Bayesian inference and a computational application (IDADE2) that requires a reference population, close in geographic and temporal distribution to the target case, to calibrate age ranges from scores generated by the technique. The inaccuracy of this method is 8 years. The direction of bias indicates the acetabulum technique tends to underestimate age. The categories 46-65 and 76-90 years exhibit the smallest inaccuracy (0.2), suggesting that this method may be appropriate for individuals over 40 years. Eighty-three percent of age estimates were ±12 years of known age; 79% were ±10 years of known age; and 62% were ±5 years of known age. Identifying a suitable reference population is the most significant limitation of this technique for forensic applications.     

Using the acetabulum to estimate age at death of adult males

The acetabular region is often present and adequately preserved in adult human skeletal remains. Close morphological examination of the 242 left male os coxae from the identified collection of Coimbra (Portugal) has enabled the recognition of seven variables that can be used to estimate age at death. This paper describes these variables and argues their appropriateness by analyzing the correlation between these criteria and the age, the intra- and interobserver consistence, and the accuracy in age prediction using Bayesian inference to estimate age of identified specimens. Results show significant close correlation between the acetabular criteria and age, nonsignificant differences in intra- and interobserver test, and 89% accuracy in Bayes prediction. Obtained estimated age of the specimens had similar accuracy in all ages. These results indicate that these seven variables, based on the acetabular area, are potentially useful to estimate age at death for adult specimens.     

Morphometric approaches to diagnosing the time of death

A new method has been used to evaluate the time of death. The relationship between the degree of autolysis of cadaveric viscera and time of death has been studied by histomorphometrical methods. The study was carried out on histological preparations of the lungs, heart, liver, spleen, and kidneys from 20 corpses of humans dead from craniocerebral injuries. Based on the results, tables were created for evaluating the time of death even at remote periods after death, when the results of other methods are unreliable.     

mRNA和microRNA在机械性窒息死推断中的研究进展

机械性窒息死的推断是法医学鉴定的难点之一。利用实时荧光定量PCR（fluorogenic quantitative RT-PCR,RT-qPCR）技术检测RNA表达水平变化规律,并据之推测机械性窒息死亡的原因,近年来已成为研究热点。本文对mRNA和microRNA（miRNA或miR）在机械性窒息死推断的研究文献进行复习综述,并重点探讨miRNA在该类死因推断中的应用,以期为机械性窒息死推断提供新的思路。     

Estimation of the time since death

The main principle of the determination of the time since death is the calculation of a measurable date along a time-dependent curve back to the start point. Characteristics of the curve (e.g. the slope) and the start point are influenced by internal and external, antemortem and postmortem conditions. These influencing factors have to be taken into consideration quantitatively in order to improve the precision of death time estimation. It does not make any sense to study the postmortem time course of any analyte without considering influencing factors and giving statistical parameters of the variability. Comparison of different methods requires an investigation of the same postmortem interval. For practical purposes, it must be concluded that the amount of literature on estimating the time since death has a reverse correlation with its importance in practice.     

Circumstances at the time of death in drug fatalities

The circumstances in drug-related deaths were investigated in this study. The basic client sample was composed of 743 drug addicts of the opiate type who had been admitted into the institute's drug-free outpatient program from 1969 to 1982. In this program, 91 clients died during the observation period. In order to be able to judge the various backgrounds adequately, a multiply subdivided classification system was developed for the death cases. Each case was recorded in three main categories: manner of death, cause of death, and phase of addiction. This was a more elaborate procedure than those commonly used since, in general, such death cases are only subdivided into a few groups that differ little from one another. Two manners of death predominated in this sample: accidents caused by poison (62%) and suicide (25%). Within in the various causes of death, poison cases prevailed (80%) and opiate intoxication (single or combined) was predominant (60%). Concerning the phase of addiction two phases were distinguished: the actual drug addiction phase (65%) and the intramural stay in prison or a hospital (25%). There were no significant sex-related differences. Various combinations regarding the mechanism of lethal opiate intoxication of drug addicts were scrutinized, concentrating on three approaches: the lack of opiate tolerance after periods of abstinence, the synergistic effect of simultaneously taking other CNS-depressant drugs, and differences in concentration in the heroin used. Our conclusions are given from the point of view of adequate counseling for drug addicts.     

Determination of the time of death in a homicide-suicide case using flow cytometry.

The study of the biologic processes involved in determining the postmortem interval also can be useful for determining the time of death. In this instance, we investigated the time of death in a case of homicide-suicide using circumstantial findings and thanatochronological and flow cytometric data. The flow cytometric data confirmed the time of death as calculated from the police investigations. This method has proven more reliable than thanatochronological techniques and can be used to supplement these observations. This case indicates that the use of flow cytometry "on the spot" is useful and reliable; however, more evidence is needed to support this new, although to date very sound, method of investigation.     

Stomach contents and the time of death. Reexamination of a persistent question

The inspection of the contents of the stomach must be part of every postmortem examination because it may provide qualitative information concerning the nature of the last meal and the presence of abnormal constituents. Using it as a guide to the time of death, however, is theoretically unsound and presents many practical difficulties, although it may have limited applicability in some exceptional instances. Generally, using stomach contents as a guide to time of death involves an unacceptable degree of imprecision and is thus liable to mislead the investigator and the court.     

Evaluation of sudden death in epilepsy

Records of the Office of the Chief Medical Examiner of the State of Maryland were reviewed for all cases of natural deaths due to epilepsy occurring in 1981 and 1982. Cases involving unclear seizure history, alcoholism, or other superimposed disorders were excluded. Twenty-nine cases were accepted and analyzed with respect to age, race, sex, circumstances of death, neuropathology, and anticonvulsant therapy. Most cases involved black males, the median age at death was 26 years, and the vast majority died in bed or in the bedroom. Less than half of these individuals had neuropathological lesions. Most had detectable levels of anticonvulsants in post-mortem blood; more than half the decedents with detectable levels of phenobarbital showed therapeutic levels of this drug.     

Cathepsin activity in the myocardium and skeletal muscles as a sign of the time of death

Determination of postmortem interval according to the time course of cathepsins activity within 5 days since death was carried out using myocardium and skeletal muscles of white breedless rats and cadavers of people who died of craniocerebral trauma. Natural time course of changes in cathepsins activity was determined which makes it possible to use these values as one of criteria in determination of postmortem interval.     

脑温死亡时间测定仪的研制

目的研制脑温死亡时间测定仪。方法根据动物和尸体实验了解脑温下降的规律,并选择针状温度传感器,确定测温入径途径。结果针状传感器的优点是:快速敏感、准确性高、对组织破坏少、插入方便。尽管这种方法仍有误差,但它与现在法医学上常用的方法相比误差已减少了许多。结论所研制的死亡时间测定仪具有体积小,便于携带、探头灵敏,可以迅速方便地探测死者的脑温,并能直接推断死亡时间,避免了某些人为的因素造成的误差。     

Historical aspects of the determination of the time of death

The origins of the determination of the time of death are presented with special reference to the signs of death, rigor mortis and body cooling, as well as to the supravital electrical response of skeletal muscle. The systematic method for future research resulting from these old experiments is presented, with the aim of making a more precise estimation of the time of death by standardization of the influencing factors.