死后组织DNA变化与死亡时间关系的研究

为调查死后组织DNA含量变化与死亡时间的关系,本文采用流式细胞仪对死后0～96小时(0～96hourpostmortem,hpm)大鼠的骨骼肌、脾、肾细胞DNA含量进行分析,结果表明,各组织显示了随死后间隔时间延长,含碎片DNA细胞增多,含完整DNA细胞减少的趋势;DNA降解系列组方图分析结果表明,脾组织降解速度明显快于肾和骨骼肌组织;骨骼肌在制成单细胞悬液过程中的人为损伤,可造成DNA提前降解.     

A preliminary investigation on the distribution of cannabinoids in man

An LC/MS/MS procedure to determine THC along with its major metabolites 11-OH-THC, THC-COOH and its glucuronide as well as the cannabinoids CBD and CBN was applied to 5 post mortem cases to study their distribution into some less commonly studied matrices. Analytes were determined in fluids and tissue homogenates following protein precipitation and liquid-liquid extraction. Gall bladder fluid exhibited maximum concentrations of all analytes except THC, which was detectable in high concentrations in muscle tissue along with CBD. THC was also present in lung specimens, whereas its concentration in liver samples was low or not detectable at all. Liver und kidney specimens contained appreciable amounts of THC-COOglu. Findings from bile support extensive enterohepatic recirculation of the glucuronide. Muscle tissue seems an interesting specimen to detect multiple cannabis use, and brain may serve as an alternative specimen for blood; nevertheless, the present findings should be substantiated by further investigations.     

Post mortem determination of bromureides (author's transl)]

Concentrations of carbromal, carbromide and bromisoval are determined in blood, urine, brain, kidney and muscle taken at autopsy from 41 fatal cases after overdosage of bromureides. In addition values of total bromine in blood are presented. Contents of total bromine can only lead to the deduction that a chronical abuse of bromureides is existent or not. Concentrations of bromureides and carbromide show a wide range according to the different time between taking the drug and death particularly in cases of pure carbromal intoxications which sometimes cause death after several days. In such cases quantitative determination of carbromide, a pharmacologically active metabolite of carbromal, is the only way to prove an acute carbromal intoxication. Especially in cases of additional foreign substances death may occur in early the phase of poisoning. Bromureides decompose post mortem by putrefaction a high degree so that the condition of the cadaver is important. Brain tissue is the most usable material for examination but other organs, particularly muscle and kidney, can be analysed with success. For differential diagnosis fatal cases are presented which were not caused by drug intake.     

Estimating time of death from measurement of the electrical excitability of skeletal muscle.

Post-mortem contraction was measured using sensitive force transducers inserted into human muscle. The muscle was stimulated using rectangular impulses of 1 sec duration and known current intensity. After some time, a noticeable change of the muscular contraction occurred, from a two-peak to a one-peak shape. The maximum force of the muscular contraction using a stable current intensity decreased with time since death, but relaxation time increased. The decrease of the maximum force and the increase of the relaxation time were used as criteria for extrapolating the time since death in a random sample of 50 bodies. The calculated 95% limits of confidence were 2.85 h (decrease of the maximum force) and 2.7 h (increase of relaxation time) up to 13 hours post mortem. The calculated 95% limits of confidence were checked on an independent sample of 21 bodies and proved to be reliable.     

Ultrastructural pathology of mechanical skeletal muscle damage

In continuation of previous light microscope investigations the question has been raised whether the criteria determined for vital muscle damage using light microscopy, could be verified and perhaps extended for the ultrastructural region. In addition to existing human pathological material taken early post mortem, muscle tissue obtained from animal experiments was also examined. The evaluation concentrated on the muscle cells, the cell organelles and the contractile apparatus. An evaluation of semi-thin-sections was carried out in parallel. The following reaction patterns could be defined as vital reactions: hypercontraction bands, zones of rupture in narrow topological relationship to organelle changes, microstructure changes with disintegration of the fibre structure, subsarcolemmic and interfibrillary oedema, decomposition of the sarcolemma. The earliest vital reactions were detectable after only a few minutes survival time. The comparison between the results of animal experiments and human pathology and the application of the results to forensic pathology will be discussed.     

Supravital electrical excitability of muscles

A new method of postmortem electrical stimulation of muscles, measuring the force of the reaction against time, is presented. Preliminary investigations have yielded the following results: The maximum force of reaction in response to a definitive stimulation, measured by a sensitive force transducer, decreases in proportion to the post mortem interval. Using this method, the mechanical reactions of muscles by electrical stimulation can be demonstrated over a much longer postmortem period as these movements are visible. The duration of postmortem reaction of different muscles seems to be much more uniform than was previously assumed. Occasionally, reactions of the M. orbicularis oculi can be seen for the longest time. The basal muscular tonus changes relative to time. The time course of a single force reaction also changes relative to the postmortal interval: the reaction becomes slower. It has been theoretically established that measurement of influencing factors such as temperature and pH in the tested muscle will enable the time of death to be more precisely estimated.     

Estimation of the post mortem period by multiple-site temperature measurements and the use of a new algorithm

The estimation of the post mortem period, in cases where death occurred under suspicious circumstances, is usually attempted using temperature measurements taken at a single body site. Early investigations of the validity of such an approach use the abdominal skin surface, the axilla and the rectum as measurement sites (B.H. Knight, Forensic Sci. Int., 36 (1987) 47-55). However, it has recently become more common to use the rectum alone, though the ear and the nasal passages have also been utilized. Whatever site is employed, the estimates are frequently found to be inaccurate. There are several fundamental reasons for these inaccuracies, the most prominent being the unknown variation in the ambient temperature between the time of death and the commencement of measurements, and the unknown body temperature at the time of death. This paper proposes a method of overcoming the above difficulties by taking a series of measurements concurrently at a number of body sites, a technique used by several previous workers (B.H. Knight, Forensic Sci. Int., 36 (1987) 47-55). Initial investigations have shown that an improved estimation of post mortem period is obtainable by the application of a suitable decision-making algorithm.     

Post-mortem changes in skeletal muscle protease and creatine phosphokinase activity — A possible marker for determination of time of death

The pattern of change in activity of two enzymes in rat skeletal muscle during body storage after death has been determined. Myofibrillar protease activity was found to increase linearly with time of storage post mortem at room temperature but not at 4 °C. In contrast, creatine phosphokinase activity declines linearly with time, and again storage at 4 °C prevented the change in enzyme activity. Starvation of animals for 5 days or forced exercise prior to death did not markedly alter the rate of change in activity of the two enzymes, although creatine phosphokinase specific activity at time of death was higher in the starved and exercised rats as compared to control animals. A plot of the logarithm of protease/creatine phosphokinase specific activities ratio versus time post mortem yields a linear curve at room temperature. These observations offer a potential method for estimating time of death.     

Morphologic identification of mummified tissue traces

Post mortem tissue samples from various human organs (skin, muscle, liver, kidney, brain) were stored at room temperature for a period of one year. During this time the samples were regularly histologically tested. Without any pretreatment of the samples a histological preparation and identification was no longer possible after only a few hours. By the use of a rehydration solution consisting of absolute ethanol (30 ml), aqua dest. (50 ml) and 0.2 M phosphate buffer pH 7.0 (20 ml) a reconstitution and identification was again possible. Further immunhistochemical examinations were also unaffected by the solution. The use of microwave stimulation allowed a reduction of the rehydration process from 24 hours to only 4 hours.     

Haptoglobin typing of human bloodstains using a specific DNA probe

The stability of DNA in human bloodstains and various post mortem tissues has been investigated. High molecular weight (HMW) DNA was usually recovered from dried bloodstains, even those up to a few years old, but very rapid degradation was found to occur post mortem in the liver, pancreas, spleen and kidney. Other tissues such as the heart, thyroid and skeletal muscle were found to give a reasonable yield of HMW DNA during the first few days after death. The feasibility of using DNA extracted from forensic bloodstain specimens for the detection of DNA polymorphisms was explored using a human haptoglobin (Hp) alpha chain specific probe. Using HindIII and XbaI digests the Hp genotypes Hp2, Hp1F and Hp1S were distinguished by Southern blot analysis in DNA prepared from 1 cm2 bloodstains up to 15-18 months old.     

Palatal rugae as an individualising marker: reliability for forensic odontology and personal identification

Personal identification is based on the comparison between ante mortem and post mortem data which can be considered unique for each individual: palatal rugae represent a useful element for such a comparison, thanks to their apparent low variability with time and unique patterns. Literature however is scarce.This pilot study aims at assessing the reliability of palatal rugae in time and at developing an identification method based on their comparison. Two casts from the upper dental arch of 39 subjects were obtained in different periods of time; at their first cast, 85.2% of patients were less than 16 years old. The second cast was performed after a period of time which varied between 4 and 65 months later than the first cast. The first cast can be taken to simulate ante mortem information, the second post mortem information. Every cast was then digitised with a scanner. In the digital images the palatal rugae were highlighted by using Adobe® Photoshop® 7.0 software; each image was coded and a comparison between “simulated” ante mortem and post mortem data was performed. In all cases ante mortem and post mortem data from the same individual were correctly matched.The study seems to indicate that this technique is highly reliable and user friendly, even on subadults, where growth processes seem not to affect the specific morphology of palatal rugae.     

The speed of post mortem change to the human skeleton and its taphonomic significance

The aim of this study was to assess the potential speed of post mortem alteration to skeletal microstructure by examining human material drawn from differing environmental contexts and time periods. The material was taken from terrestrial, intertidal and lacustrine contexts and extended over a range of 3 months to 83 years post mortem. The examination was conducted using backscattered electron imaging which provided information on microstructure and relative density. The results from this study have significantly brought forward the time of known onset for post mortem alteration for 3 morphological types of microstructural change, the earliest of which was 3 months post mortem. The contribution of the depositing environment was also shown to influence significantly the microstructural/ morphological type of post mortem alteration. It is hypothesized that microstructural changes to bone could occur within days of death as a result of endogenous bacterial migration to the skeleton. Further studies are required to establish definitively the earliest moment that such change can occur prior to skeletonisation.     

Macroscopic findings for the exclusion of a forensic relevant soil embedded resting period in skeletal remains--an approach based upon literature

A reliable determination of the post mortem interval (PMI) in human bones has neither been found by morphological nor by intensive analyses of other kinds. In most cases of legal medicine practice the question of PMI is restricted to a forensically relevant resting period. In a survey based upon literature, all osteological signs of decomposition, which have not been described for a soil embedded resting period of under 50 years, were collected. 21 research reports could be found, describing macroscopic findings on soil-embedded human bones with known PMI. All in all, 1295 individuals were examined in these investigations. A censorious review of the summarized results found in literature reveals that the following findings have never been seen in a PMI of 50 years or less. Outer appearance: macroscopically no adipocere, deep incisions of the outer compact layer, extensive defects of the bone surface, intense brownish-black lawn of microorganisms, fraying of the outer lamellar system, lifting of the cortical area, torsion of the tissue, attached brushit, bone manually breakable. On freshly sawn cross sections: lack of adipocere, brushit in the marrow area, reduced or lack of UV-fluorescence.     

Pushing the Dead into the Next Reproductive Frontier: Post Mortem Gamete Retrieval under the Uniform Anatomical Gift Act

In re Matter of Daniel Thomas Christy authorized post mortem gamete retrieval under the most recent revision of the Uniform Anatomical Gift Act. This article recommends that the National Conference of Commissioners on Uniform State Laws explicitly address the issue of post mortem gamete retrieval for reproductive purposes; that legislators specify whether their states will follow the Christy ruling; and that ethics committees and consultants prepare for the questions about human identity and self determination that post mortem gamete retrieval raises.     

Digital autopsy archive using the personal computer

The development of a dissection register for Legal medicine well differentiated and considering special requirement of the subject was not achieved in history because of complexity of post mortem findings in many cases. Realizing that an all satisfying concept failed we looked for the possibility of using electronic data processing for rapid and flourish collection of autopsy results not requiring much time for the coroner. Based on personal computer software "dBase" a database program was developed easy to handle using different forms asking for characteristic circumstances of the case and essential post mortem findings. Short codes for locations and ascertainments were chosen to enable rapid selection of interesting statements as far as handling for statistical evaluations later on. Less then 10 minutes are needed for recording post mortem results in this way short time after autopsy.     

Classification of digoxin concentrations in blood and tissues in cases under suspicion of poisoning

The clarification of a suspicion of poisoning at all times poses a problem to the forensic toxicologist, when a narrow margin of therapeutic safety and a low dosage coincide as in cases of digoxin poisoning. Statistical methods may serve as an aid. The post mortem digoxin concentration in the tissues of heart, kidney, liver and in blood of 45 patients who had received therapeutic daily doses and of 13 cases of fatal poisoning are compared. After logarithmic transformation of the individual concentration values a two modal distribution is obtained. There is one concentration calculated with equal probability of being classified to "therapeutic or toxic", as well as the probability of observing the "critical" concentrations of 400 ng digoxin/g cardiac tissue, 500 ng/g kidney and 250 ng/g liver after therapeutic dosing. Using the discriminant analysis each of the cases clearly falls into one of the two collectives "therapeutic" and "toxic", when taken as a separate observation. Concentration data of fatal poisonings taken from the literature are as successfully classified as the analytical results of some exhumed bodies under suspicion but not poisoned. As expected the power of discrimination increases with the number of parameters. Because of the relatively slow body distribution of digoxin the blood taken from peripheral vessels is of most important evidence.     

Postmortem exsiccation of the fingertips--results of a systematic quantitative and qualitative experimental study

To date there have been no results published on qualitative and quantitative time-related changes with regard to desiccation of human fingertips post mortem. The fingertips of 52 hands from 36 corpses were qualitatively examined soon after death (2-6 h) to 120 h post mortem. The quantitative investigations were confined to the tips of the middle fingers. The width of three adjoining ridges of the skin was measured in four defined areas of the middle fingertips, and photographs were taken at intervals of 2, 3, 4, 5, 6, 7, 8, 12, 20, 26, 32, 44, 50, 60, 72, 84, 96 and 120 h p.m. Concerning the qualitative test results, four time-related stages were classified macroscopically and by a pocket lens (X25). Desiccation stage IV correlates to the period 72 h after death in bodies found in apartments. Besides the rough, wrinkled, and brown or black surface of the fingertips, microwrinkles of the epidermis occur on the skin ridges, which have so far not been described. The quantitative results did not show any changes in the width of the skin ridges, independent of age, sex, right or left hand.     

Deaths among narcotic addicts in Denmark in 1978 and 1979

Objective measurements were carried out to study the evolution of rigor mortis on rats at various temperatures.Our experiments showed that:(1) at 6 °C rigor mortis reaches full development between 48 and 60 hours post mortem, and is resolved at 168 hours post mortem; (2) at 24 °C rigor mortis reaches full development at 5 hours post mortem, and is resolved at 16 hours post mortem; (3) at 37 °C rigor mortis reaches full development at 3 hours post mortem, and is resolved at 6 hours post mortem; (4) the intensity of rigor mortis grows with increase in temperature (difference between values obtained at 24 °C and 37 °C); and (5) at 6 °C a “cold rigidity” was found, in addition to and independent of rigor mortis.     

Death certificates in Germany, England, The Netherlands, Belgium and the USA

Every country has its own legal system regarding post mortem examinations and death certificates. The authorities want to know the cause and the manner of death of their citizens and especially whether someone is responsible for the death of someone else. In this article a comparison is made between the legal regulations in the Netherlands, Belgium, Germany, England and the USA. Specific attention is given to the following aspects: which official performs the post mortem exam, what is the role of the attending physician by issuing the death certificate and how is the privacy of the deceased protected.