A study on estimation of time since death after histological examination of kidney.

Background: Estimation of time since death is one of the most important object of post-mortem examination. Many degenerative changes begin to take place in the body immediately or shortly after death. Kidney is one of the most important excretory organs of human body, its undergo series of gross as well as histological changes. Methods: This study was performed in department of anatomy in close association with the department of forensic medicine & toxicology and pathology, Pt. J. N. M. medical college and DBRAM hospital Raipur (C.G.) India, during study period November 2012 to October 2013. Study was done on 50 human cadavers (Study subjects). Kidney was obtained from dead bodies during post-mortem examination. In each case kidney was studied histologically. Data was compiled in MS excel and checked for its completeness and correctness and then it was analyzed. Results: In 48-60 hour increasing temperature, one case show very severe change was seen. Microscopic changes in kidney were increasing (mild to moderate, moderate to severe, severe to very severe) as temperature increases. Conclusion: In the present study earliest remarkable postmortem histological changes were seen in DCT. Finding of present study will be useful for forensic experts.

A study of pericardial fluid enzymes activities after death and their correlation with post-mortem interval.

The estimation of time since death at the time of autopsy has been and remains to be one of the challenges to the Forensic Pathologist. .A prospective study was undertaken in SMS Hospital, Jaipur on activity of Pericardial Fluid enzymes after death in deceased. A total of 50 study cases were randomly selected after screening. The pericardial fluid was examined biochemically for enzyme activity of Amylase, Creatine Kinase (CK), Gamma-glutamyl Transferase (GGT) and Lactate Dehydrogenase (LDH) enzymes by photoelectric colorimetry method. The enzyme activity levels so obtained were charted and statistically studied and graphical records obtained against known post-mortem interval. The data thus obtained was analysed with a view to ascertain whether such assays could be of any help to estimate time since death routinely. In this study we observed a positive correlation of all the four enzymes with the time elapsed after death of which rise in CK was found to be statistically significant.

Serum enzymes changes after death & its correlation with time since death.

Estimation of time since death is one of the primary objectives of an autopsy. Forensic Scientists and researchers have been persevering hard to find out methods of accurate determination of postmortem interval since long. However, the concept of “Postmortem Clocking” so far seems to be a distant dream only. The favorite biological fluids, to study postmortem biochemical changes, have been those which withstand putrefactive changes for longer duration, like vitreous humor, cerebrospinal fluid, pericardial fluid etc. In blood, markers like electrolytes, urea, creatinine, glucose etc have been more commonly studied. Enthusiastic studies have been undertaken by various researchers to find out reasonably reliable methods of estimating postmortem interval by studying serial quantitative changes in serum levels of various enzymes and to extrapolate the data obtained therefore in terms of duration of death. However, the accuracy of such an opinion remains big area of concern even today, as the range of duration is mostly too wide to be practically useful.

Polynomial regression model to estimate time since death in adults from rectal temperature in Chandigarh zone of Northwest India.

Estimation of time since death from rectal cooling with the help of polynomial regression model is the subject of discussion in the present study. Though in literature various models are available but their complex modeling structure and calculation, restricted their application for real life situations, particularly in climatic conditions where the room temperature varies between 60.33o to 91.97 o F like of Chandigarh zone of India. The present study is an attempt to provide a suitable model for estimation of time since death in such conditions. Nonetheless, with the help of polynomial regression model, time since death can be estimated with SE estimate of 0.12947 hours and 0.410277 hours in summer and winter respectively. Moreover, this model has produced smaller confidence and prediction intervals.

Double logarithmic, linear relationship between postmortem vitreous sodium/potassium electrolytes concentration ratio and time since death in subjects of Chandigarh zone of Northwest India.

Present authors had recently demonstrated a highly significant double logarithmic linear relationship between time since death and serum sodium/potassium concentration ratio and also with the serum chloride concentration in humans. Consecutively the present study was carried out to substantiate this disposition in vitreous humour. The data on postmortem vitreous sodium/potassium electrolytes concentration ratio in 1026 subjects, revealed a highly significant relationship between logarithm of vitreous sodium/potassium electrolytes concentration ratio and logarithm of time since death upto 66 hrs. of death. Postmortem interval can be predicted from vitreous sodium/potassium electrolytes concentration ratio with standard error of estimate 0.1800 hrs. However, factors like environmental temperature, age & gender also influences it significantly.

A study of serum enzymal changes after death and its correlation with time since death.

A prospective study was underteken as a part of postgraduate thesis work on quantitative serum enzymal changes after death in the Deptt. of Forensic Medicine GMC Bhopal (M.P.) in 1999-2002. A total of one hundred study cases and ten control cases were randomly selected after screening. The sera was assayed biochemically by photoelectric colorimetry for an imotransfereases (AST & ALT) and serum acid phosphatase. The enzymal levels were plotted against known postmortem interval. The graphical records were studied with a view to ascertain whether such assyas could be of any help to calculate time since death routinely.

Changes in the levels of vitreous potassium with increasing time since death.

This study was done to know the changes in the levels of potassium in the vitreous humour of eye with increasing time since death by flame photometry method. 200 cases brought to the mortuary of Govt. Medical College, Patiala, formed the material of this study. The cases were divided in 2 groups, burn cases (24) and non-burn cases (176). The data thus collected was analyzed statistically. It was found that the vitreous humour potassium concentration was increasing in a linear fashion with increasing time since death and this increase in the level was independent of the factors like age, sex, environmental temperature and humidity.

Synchronous use of maggots and diatoms in decomposed bodies.

The use of maggots and diatoms conjointly has proved to be an important factor in the medicolegal cases referred with advance decomposition. In practice it is quite much difficult to determine Post Mortem Interval (PMI) and as well as to ascertain ante-mortem drowning factor in the bodies, which are being recovered with advance putrefaction. However the analysis of co-existing evidences associated with corpses viz: Maggots and diatoms may reveal to draw fairly sound inferences, relating to PMI and drowning mode of death as well, especially in the decomposed bodies. Otherwise, it would not be possible to solve the cases of this nature. The present paper enumerates the two case studies recently reported in year 2003 emphasizing about the medicolegal application of both the evidences simultaneously in the cases with advance decomposition.

Estimation of the postmortem interval by determining nuclear DNA degradation from bone marrows and brains in rats / 中国法医学杂志

Objective To detect nuclear DNA degradation of bone marrows and brains in rat cadavers at different temperatures,and develop a new parameter for estimating early postmortem interval(PMI).Methods The brain and bone marrow were taken out for every 4h,during 0~40h after death at 10℃ and 20℃,respectively.And the single cell gel electrophoresis(SCGE) was carried out to detect the nuclear DNA degradation.Linear regression analysis was used to assay the relationship of the comet parameter HeadDNA%,Tail Length(TL) and Olive TailMoment(TM) with PMI.Results Different decline degrees of comet HeadDNA% were found in both brain cells and bone marrow cells after death,the decline of HeadDNA% in brain cells at 20℃ was faster.Compared with degradation in marrow cells,the linear relation between degradation of brain cells and PMI was better.Conclusion with that of comet parameters TL and TM,the perfect linear relationship between HeadDNA% and PMI was also observed.Conclusion Brain tissues are more suitable for PMI estimation by detecting degradation of DNA with SCGE.The HeadDNA% is more valuable for PMI estimation than TL and TM.

Investigation of the sarcosaphagous fly in Guizhou Province / 中国法医学杂志

Objective To investigate the fly in relation to cadaver in the area of Guizhou. Method According to entomological investigation method, 12 areas were selected for investigation, where specimens were collected from 10th to 20th in February, May, August and November in a year. Results 37433 sarcosaphagous fly specimens were collected in 12 areas in a year, which were classified into 27 species of 17 genera in 5 families.Conclusion Data on the sarcosaphagous fly species, area- and season-related distribution were obtained, which is reported first time in China. and may form a basis for further study on the development of sarcosaphagous fly and provide reference to estimation of possible season and circumstance when death occurred.

DEGRADATION KINETICS OF ACONITINE IN THE SAMPLE OF RABBITS / 西安交通大学学报(医学版)

A high performance liquid chromatography (HPLC)has been used to determine aconitine in the sample of rabbits. Kinetics of degradation of aconitine in vitro was studied. The degradation of aconite from the poisoned specimens (coagulated blood, liver) treated differently in vitro was characterized by pseudo-secondorder kinetics. The K. of aconitine in these samples was the biggest in the fixed section of 4% aqueous solution of formaldehyde (1.5619, O.7728?g/d), bigger in the fixed section of 95% alcohol(0.4891, 0.07536?g/d) and the smallest in the refrigerator at 4℃ (0.06372, 0.03903 ?g/d), respectively. That is, aconitine in the poisoned samples was decomposed slowly in the refrigerator and secondly in the fixative of alcohol. Amount of aconitine might be extrapolated from the result of examination of specimens taken from the subject after poisoning or killing by the poison, using the kinetics equation.