Application of a computer assisted image analyzer to the assessment of area and number of sites of dental attrition and its use for age estimation

A simple method was devised to assess dental attrition in terms of its area and number of sites by using dental plaster casts and a computer assisted image analyser. The changes presented on the occlusal surfaces of teeth were investigated for age estimation using these criteria. The area of attrition on each tooth demonstrated a significant positive correlation with age, but a wide individual variation was observed in the values for each tooth. Therefore, this method was unsuitable for accurate age estimation of a single tooth. A strong negative correlation with age was observed in the number of sites of attrition. A multiple stepwise regression analysis using the variables 'attrition area' and 'attrition number' revealed multiple correlation coefficient values of 0.93. The quantitative assessment of both horizontal and vertical factors of dental attrition would be essential to improve the accuracy of this method.     

The influence of putrefactive changes on the determination of Paraquat in autopsy materials

This paper describes how the putrefactive changes in a cadaver will influence the determination of Paraquat in autopsy material. The carcasses of rats that had been given large doses of Paraquat and subsequently killed by cervical dislocation, were left at room temperature for up to seven days. Samples of stomach, caecum and liver were removed for the colorimetric determination of Paraquat with sodium dithionite following extraction on a Dowex 50W-4 column.Paraquat recovered from the stomach and caecum showed a decrease with time after death with the rate of decrease being greater in the caecum samples. However, the concentration of Paraquat in the liver increased for three days and then began to decrease gradually.The possible causes of these variations in Paraquat recovery are discussed. The findings appear to demonstrate the value of Paraquat determination even in samples from material that is in a state of advanced putrefaction.     

An accidental death due to Freon 22 (monochlorodifluoromethane) inhalation in a fishing vessel

We have firstly presented a case using post mortem corrosive method in forensic medical practice after coronary stent implantation. Occlusions, fate of side branches could be detected during the clinical diagnostic angiography, intravascular ultrasound, computed tomography; however, the forensic medical determination of cause of death, identification of complications needs a careful post-mortem investigation. The injection-corrosive method seems to be a useful assistance in the characterisation of pathomorphological changes after stent implantation. Besides the classical techniques of histology, immunohistochemistry, electron microscopic investigation we have introduced a new synthetic resin corrosion cast method. This three-dimensional corrosion cast preparation may provide new data about the actual morphological condition of the coronary vessels and a better understanding of the pathomechanisms of sudden cardiac death after percutaneous coronary intervention.     

Pharmacokinetic profile of paraquat following intravenous administration to the rabbit

Pharmacokinetic studies of paraquat in rabbits were performed using [methyl-14C]-paraquat. Plasma concentration of paraquat following i.v. administration to the rabbit was fitted to a 3-exponential function of pharmacokinetic analysis. Distribution and elimination were discussed on the basis of the 3-compartment open model system, which has a central and two peripheral compartments. Computer simulations of paraquat levels in each compartment indicated that the slow-uptake peripheral compartment contained a greater amount of paraquat than the central or the fast-uptake peripheral compartment. On the basis of the present results of the computer simulations in company with tissue distributions of paraquat reported by the other investigators, it is likely that the slow-uptake peripheral compartment contains the lung. In cases of paraquat-induced renal failures, the paraquat levels of the slow-uptake peripheral compartment were remarkably higher than in cases of normal renal functions. Histology of the rabbit tissues 7 days after i.v. administration of paraquat revealed that marked changes were observed only in the kidney, suggesting some renal failures induced by paraquat. In spite of the high concentration of paraquat, which was presumed with the computer simulations in this study, the rabbit lung showed a remarkable resistance to paraquat toxicity. The histology studies suggested the complexities of paraquat toxicity to the rabbit. The lung toxicity in the rabbit would be caused by not only the paraquat concentration in the lung but also some biochemical parameters in the tissue related to the mechanisms of paraquat toxicity.     

Suicidal carbon monoxide inhalation of exhaust fumes. Investigation of cases

The inhalation of automobile exhaust gases is a relatively frequent suicidal method. Two such cases of special interest to forensic pathology and toxicology have been introduced. In case 1, a suicide note disclosed the victim's mental state, the inside conditions of the car, and toxic effects of automobile exhaust. In case 2, a reconstruction experiment has revealed important factors for the investigation of the scene, such as the size of a vinyl hose, the conditions of connecting site of the hose with the exhaust pipe, etc.     

Postmortem absorption of drugs and ethanol from aspirated vomitus--an experimental model.

Using human cadavers an experimental model was developed to simulate the agonal aspiration of drug- and alcohol-laden vomitus. By needle puncture, an acidified (N/20 HCl) 60-ml slurry of drugs (paracetamol 3.25 g, dextropropoxyphene 325 mg) and ethanol 3% w/v was introduced into the trachea. After 48 h undisturbed at room temperature, blood samples were obtained from ten sites. Ethanol and drug concentrations were highest in the pulmonary vessels in all five cases studied. Pulmonary vein mean ethanol was 58 mg% (range 13-130), paracetamol 969 mg/l (range 284-1934), propoxyphene 70 mg/l (range 11-168). Pulmonary artery mean ethanol was 53 mg% (range 10-98), paracetamol 476 mg/l (range 141-882), propoxyphene 29 mg/l (range 7.6-80). Ethanol and drug concentrations in aortic blood were higher than in the left heart and concentrations in the superior vena cava were higher than in the right heart, suggesting direct diffusion into these vessels rather than diffusion via the pulmonary and cardiac blood. Potential interpretive problems arising from this phenomenon can be avoided by using femoral vein blood for quantitative toxicological analysis.     

Clocapramine-related fatality. Postmortem drug levels in multiple psychoactive drug poisoning

A suicide caused by ingestion of multiple psychoactive drugs is reported. A 42-year-old man with a history of psychosis was found dead in a blood pool in his room. The forensic autopsy revealed two stab wounds on his chest. However, these wounds could not explain the cause of death. Eighty-six tablets were found in his stomach. Four psychoactive drugs; clocapramine (CC), chlorpromazine (CP), promethazine (PM) and clotiazepam (CT) were detected in blood and tissues. The concentrations of CC, CP, PM and CT in the femoral vein (FV) blood were 0.39, 0.61, 1.23 and 0.09 microg/ml, respectively. The cause and manner of death were attributed to suicidal multiple psychoactive drug poisoning.Postmortem drug redistribution showed great site-dependent variations with the lowest level in the FV blood. Remarkable variations were observed in CC, CP and PM, but not in CT compared to other three drugs. The variations were dependent on the volume of distribution (Vd) of the drugs. Our human case has demonstrated drugs with higher Vd values showed higher degree of postmortem redistribution of the drug and vice versa.     

A rare fatal case of wood preservative,monochloro-naphthalene (MCN), poisoning

A rare case of poisoning by the wood preservative Xylamon^® TH-Clear (active ingredient: 60% 1-chloronaphthalene) is reported.A mentally disordered carpenter, 44 years old, ingested an unknown amount of Xylamon^® and died in about 2 hours. Analysis for 1-chloronaphthalene was performed by TLC, IR and GC methods. GC analysis for 1-chloronaphthalene showed the concentration in the peripheral blood to be 2.46 μg/ml and the bile concentration to be 75.5 μg/ml. The total amount in the stomach contents was 27.7 g.     

Quantitative evaluation of volatile hydrocarbons in post-mortem blood in forensic autopsy cases of fire-related deaths

Volatile hydrocarbons in post-mortem blood from victims of fires were analyzed quantitatively by headspace gas chromatography mass spectrometry. The benzene and styrene concentrations in the blood were positively correlated with the carboxyhemoglobin (CO-Hb) concentration, which is evidence that the deceased inhaled the hydrocarbons and carbon monoxide simultaneously. By contrast, the concentrations of toluene and CO-Hb in the blood were not significantly correlated. This lack of correlation could be explained by two different sources of toluene, with low blood concentrations of toluene arising when the deceased inhaled smoke and high blood concentrations of toluene arising when the deceased inhaled petroleum vapor or other unknown vapors. The quantity of soot deposited in the respiratory tract was classified into four grades (-, 1+, 2+, 3+). The mean CO-Hb concentration in the 1+ soot group was significantly lower than those in the 2+ (p<0.05) and 3+ (p<0.01) soot groups. The blood CO-Hb concentrations in the 1+ soot group were all below 30%. Those indicated that the deceased aspirated smoke that contained both soot and carbon monoxide. The wide variation in CO-Hb concentrations for each soot classification could be caused by the different types of smoke produced by different materials. For example, petroleum combustion with a limited supply of oxygen, like in a compartment fire, may produce a large volume of dense black smoke that contains a large quantity of soot. Soot deposits in the airways and the blood CO-Hb concentration are basic and essential autopsy findings that are used to investigate fire-related deaths. The quantitative GC-MS analysis of blood volatile hydrocarbons can provide additional useful information on the cause of the fire and the circumstances surrounding the death. In combination, these three findings are useful for the reconstruction of cases.