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961.
When two human corpses are found in temporal and locational context the assumption of a non-natural cause of death is close at hand. Suicide, extended suicide, homicide or accident (particularly with carbon monoxide) come to mind. When, however, a natural cause of death emerges for both after autopsy and further examinations, this provokes the question whether this incidence is coincidental. In our two presented cases, a married couple each was found dead together. In both cases, the wife needed nursing and was being cared for by a husband who died of cardiac disease shortly before the wife died. In one case, the wife died of acute uncompensated chronic congestive heart failure. In the other case, the cause of death of the wife was hypovolemic shock due to acute gastrointestinal bleeding from recurrent gastric mucosal erosion. It is to be discussed for both cases whether, given the pre-existing illness, the acute stress of the situation in view to the husbands' death may at least have favored the occurrence of death and may, thus, have led to the criminologically conspicuous situation of finding.  相似文献   
962.
Adipocere formation is well known as a later post-mortem change. We experienced a female victim who had been sealed up in a clothes box for approximately 4 years. We collected several subcutaneous fats as well as visceral fats from the victim to investigate adipocere formation. Fresh subcutaneous fats of one female and five male victims who suddenly died were used as the control. These samples were homogenized and the lipids were extracted with chloroform and methanol followed by injection into gas chromatography-mass spectrometry and gas chromatography. We detected a hydroxy fatty acid in the fat of the case, but not in the controls. Using standard synthetic hydroxy fatty acid, the lipid extract component was identified as 10-hydroxyoctadecanoic acid (10-OH 18:0) and this concentration was quantified. Consequently we confirmed that adipocere was formed much slowly in dry concealment. In addition, the fatty acid composition was compared with the control. Most of the linoleic acid (18:2) disappeared and a peak developed instead. Using standard synthetic fatty acid, this peak was identified as cis-12-octadecenoic acid (cis-12-18:1). This suggests that linoleic acid is hydrogenated to cis-12-octadecenoic acid in the process of adipocere formation.  相似文献   
963.
Ethyl glucuronide (EtG) is a minor metabolite of ethanol that can be detected in hair. In some specific situations, head hair can be missing, and therefore, alternative anatomical locations of hair are of interest. In this study, paired hair specimens (head hair and pubic hair) from eight social drinkers were analyzed for EtG. Each sample was decontaminated by two dichloromethane bathes (5 ml) for 2 min. After cutting into small pieces, about 50 mg of hair was incubated in 2 ml water in the presence of 10 ng of EtG-d5, used as internal standard and submitted to ultra-sonication for 2 h. The aqueous phase was extracted by SPE using Oasis MAX columns. The hair extract was separated on an ACQUITY BEH HILIC column using a gradient of acetonitrile and formate buffer. Detection was based on two daughter ions: transitions m/z 221-85 and 75 and m/z 226-75 for EtG and the IS, respectively. This laboratory is using a positive cut-off at 50 pg/mg. All eight head hair specimens were negative for EtG at a limit of quantitation fixed at 10 pg/mg. Surprisingly, EtG was identified at high concentrations in pubic hair, in the range 12-1370 pg/mg. It appears, therefore, that it is not possible to document the drinking status of a subject by simply switching from head hair to pubic hair.  相似文献   
964.
Because serum Procalcitonin is reported to be a valid postmortem marker of sepsis, this prospective study was carried out to determine whether the semi-quantitative PCT-Q((R))-Test (B.R.A.H.M.S., Germany) is a reliable indicator of postmortem Procalcitonin (PCT) serum levels, thus enabling a quick "tableside" diagnosis of sepsis. Postmortem PCT-levels of 70 forensic and 78 clinical-pathological autopsy cases (n=148) were examined using the B.R.A.H.M.S-PCT-Q-Test during autopsy. 27 cases were categorized as the cases of sepsis according to the ACCP/SCCM Consensus Conference criteria. 121 cases were assigned to the non-sepsis group. Among the 148 cases, 18 samples could not be analyzed by the reason of strong hemolysis. Using a cut-off point of 2 ng/ml, 20 cases of sepsis were identified (true positive) whereas 3 cases of sepsis were not detected (false negative). In the non-sepsis group (107 cases) 6 cases showed a positive testing (false positive). When applied within 48 h postmortem, the PCT-Q-Test showed a sensitivity of 86.96% and a specificity of 94.39% (at cut-off 2 ng/ml). Likelihood ratios and positive predictive values proved to be lower in the forensic autopsy group (PPV: 59.3% in forensic case vs. 85.1% in clinicopathological cases; NPV: 98.73% in forensic cases vs. 95.2% in clinicopathological cases). The PPVs using a cut-off point of 10 ng/ml were 100% in both groups independent of sepsis prevalences. The results show, that a high NPV for prevalences ranging from 3% to 30% can be reached using a 2 ng/ml cut-off point, whereas a cut-off of 10 ng/ml ensures a high PPV for the respective prevalences in the absence of exclusion criteria. The study provides strong evidence that the introduction of rapid diagnostic test (RDTs) of postmortem PCT serum levels may be useful in achieving rapid distinction between sepsis and non-sepsis-related causes of death, especially in conjunction with the medical case history and further autopsy results. In addition, the use of RDTs enables clinicians to conduct an evidence-based validation of clinical diagnosis, thus facilitating future clinical decision-making.  相似文献   
965.
966.
The aim of the present study was to compare the accuracy, precision, and bias of two macroscopic and one histological age at death estimation methods on human teeth. The sample was comprised of 67 permanent teeth, obtained from 37 individuals aged 20-91 years. Age was predicted according to the methods proposed by Lamendin et al. (LAM), Bang and Ramm (BR), and the quantification of tooth cementum annulations (TCA). TCA was found to be most accurate in all age groups. Its mean absolute error of the estimated age was about half as high as the mean absolute error for both LAM and BR. BR achieved approximately the same mean absolute error as TCA for old adults only. LAM displayed the highest precision in the young and the old age group whereas TCA was more precise in the middle age group. TCA was found to be the most precise method when the precision was calculated for all ages. Considering the bias, all methods displayed a tendency to overestimate age in young and to underestimate it in old specimens. The exception to this rule was TCA, which provided unbiased estimates for young adults. The higher accuracy and precision recommends favouring TCA over LAM and BR, provided that the required know-how and equipment are available.  相似文献   
967.
The requirement to differentiate between incorporation and external contamination of drugs into hair is undisputed, in particular when dealing with compounds which are administered by sniffing or inhalation (e.g. cocaine). With the aim of making this discrimination, hair samples from cocaine (COC) users (group IN) and seized cocaine samples (group OUT) were compared regarding the parameters benzoylecgonine (BZE), ecgonine methyl ester (EME), ecgonine (ECG), anhydroecgonine methyl ester (AEME), cocaethylene (CE) and norcocaine (NCOC). Since most of these compounds may be minor by-products of COC or be formed by biotransformation or chemical degradation, the stability of each substance was carefully examined. COC was found to be converted into significant amounts of BZE, EME and ECG even under mild extraction conditions, while traces of NCOC proved to be a ubiquitous by-product of COC. Cocaine positive hairs and seized cocaine samples (diluted to relevant concentrations) were equally preprocessed and analyzed by LC-MS-MS. Out of the metabolites listed above, NCOC, CE and AEME (each normalised to COC) were significantly increased in the incorporation group (i.e. hair samples from cocaine users). Based on this approach, a statistical discriminant analysis enabled us to make a prediction (and estimation of uncertainty) for each cocaine positive hair sample as to its likelihood of belonging to the group of cocaine users or of being contaminated.  相似文献   
968.
The electrostatic process for imaging indentations on documents using the ESDA device is investigated under controlled experimental settings. An in-house modified commercial xerographic developer housing is used to control the uniformity and volume of toner deposition, allowing for reproducible image development. Along with this novel development tool, an electrostatic voltmeter and fixed environmental conditions facilitate an optimization process. Sample documents are preconditioned in a humidity cabinet with microprocessor control, and the significant benefit of humidification above 70% RH on image quality is verified. Improving on the subjective methods of previous studies, image quality analysis is carried out in an objective and reproducible manner using the PIAS-II. For the seven commercial paper types tested, the optimum ESDA operating point is found to be at an electric potential near -400V at the Mylar surface; however, for most paper types, the optimum operating regime is found to be quite broad, spanning relatively small electric potentials between -200 and -550V. At -400V, the film right above an indented area generally carries a voltage which is 30-50V less negative than the non-indented background. In contrast with Seward's findings [G.H. Seward, Model for electrostatic imaging of forensic evidence via discharge through Mylar-paper path, J. Appl. Phys. 83 (3) (1998) 1450-1456; G.H. Seward, Practical implications of the charge transport model for electrostatic detection apparatus (ESDA), J. Forensic Sci. 44 (4) (1999) 832-836], a period of charge decay before image development is not required when operating in this optimal regime. A brief investigation of the role played by paper-to-paper friction during the indentation process is conducted using our optimized development method.  相似文献   
969.
Some electrocution deaths occur without detectable current marks on the skin, making forensic examination to determine the true cause of death more difficult. Because arterial thrombosis was a frequent finding in victims of electrocution, we investigated injury to the endothelium of the aorta and pulmonary artery with a scanning electron microscope in five cases of death known to be caused by electrocution. We found large pores on the surface of endothelial cells of the aorta and pulmonary artery in those who died of electrocution, but no endothelial membrane perforation was found in those who died of cardiac diseases. These findings were present within 12h after death. Therefore, scanning electron microscopic evidence of endothelial perforation in the aorta and pulmonary artery could be a useful marker to identify electrocution for those victims without detectable current marks on the skin.  相似文献   
970.
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