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991.
This paper presents an overview of the organisation and the results of the collaborative exercises (CE) of the European DNA Profiling (EDNAP) Group's mitochondrial DNA population database project (EMPOP). The aim of the collaborative exercises was to determine whether uniformity of mtDNA sequencing results could be achieved among different laboratories. These were asked to sequence either the complete mtDNA control region or the two hypervariable regions HVI (16024-16365) and HVII (73-340) from DNA extracts, buccal swabs or bloodstains, proceeding in accordance with the protocol and strategies used in each individual laboratory. The results of the collaborative exercises were employed to identify possible sources of errors that could arise during the analysis and interpretation of mtDNA profiles. These findings were taken as a basis to tentatively make suitable arrangements for the construction of a high quality mtDNA database. One hundred fifty mtDNA profiles were submitted to the evaluating laboratory, and disaccording profiles were classified into four groups corresponding to the source of error: clerical errors, sample mix-ups, contaminations and discrepancies with respect to the mtDNA nomenclature. Overall, 14 disaccording haplotypes (16 individual errors) were observed. The errors included 10 clerical errors, 3 interpretation problems, 2 cases of sample mix-up and 1 case of point heteroplasmic mixture, where the 2 sequencing reactions brought inconsistent base calls. This corresponds to an error rate of 10.7% in a virtual mtDNA database consisting of the collaborative exercise results. However, this estimate is still conservative compared to conclusions drawn by authors of meanwhile numerous publications critically reviewing published mtDNA population databases. Our results and earlier published concerns strongly emphasize the need for appropriate safety regulations when mtDNA profiles are compiled for database purposes in order to accomplish the high standard required for mtDNA databases that are used in the forensic context.  相似文献   
992.
Malignant tissue samples may sometimes be the only source of biological material for forensic investigations, including identification of individuals or paternity testing. However, in use of such samples, uncertainties due to microsatellite instability (MSI) and loss of heterozygosity (LOH) often associated with neoplasias may be encountered. In this study, we have analysed the applicability of autosomal tetranucleotide short tandem repeat (STR) markers, which are routinely used in forensic analysis, to gain genetic information. MSI and LOH were analysed in 41 surgically removed gastrointestinal cancer specimens and the adjascent non-cancerous tissue marginals. The cancer specimens showed great variability in their genetic phenotypes due to MSI or LOH, with only 32% being microsatellite-stable. Of the 15 autosomal STR loci analysed, only TH01 had no MSI-type alteration in these samples. The loci most frequently affected by MSI were D8S1179, D21S11, D18S51 and D19S433 (MSI in 15-17% of cases). LOH-type alterations were observed at all of the loci, including the amelogenin locus used for sex determination. The highest LOH frequency was found at locus D18S51 (27%). The genetic alterations at the marker loci may indicate false homozygosity or heterozygosity, and false gender may result from erroneous deduction of DNA profiles. Therefore, typing of autosomal STRs from malignant tissues in forensic settings warrants careful interpretation of MSI and LOH results together with microscopic analysis of a tissue specimen. Results by two commercially available and widely used forensic DNA profiling kits used here were comparable.  相似文献   
993.
One out of every six nonelderly Americans without health insurance lives in California. The problem of access to competent and dependable health care is especially problematic among the state's minority, and especially Hispanic, population. Because one-third of the country's Hispanics live in California, how this state deals with health access issues will affect the practice and progress toward universal care in the nation as a whole. Expanding health care access to California's dependent population will involve overcoming a number of well-known administrative and fiscal obstacles, including an underfunded, highly fragmented public health care system that has developed incrementally and incoherently over decades. However, a key to understanding the problem of access to health care in California involves a story of how ethnic conflict and partisan politics often conspire to deny or discourage access for eligible women and children.  相似文献   
994.
Ballistic imaging databases allow law enforcement to link recovered cartridge cases to other crime scenes and to firearms. The success of these databases has led many to propose that all firearms in circulation be entered into a reference ballistic image database (RBID). To assess the performance of an RBID, we fired 4200 cartridge cases from 600 9mm Para Sig Sauer model P226 series pistols. Each pistol fired two Remington cartridges, one of which was imaged in the RBID, and five additional cartridges, consisting of Federal, Speer, Winchester, Wolf, and CCI brands. Randomly selected samples from the second series of Remington cartridge cases and from the five additional brands were then correlated against the RBID. Of the 32 cartridges of the same make correlated against the RBID, 72% ranked in the top 10 positions. Likewise, of the 160 cartridges of the five different brands correlated against the database, 21% ranked in the top 10 positions. Generally, the ranking position increased as the size of the RBID increased. We obtained similar results when we expanded the RBID to include firearms with the same class characteristics for breech face marks, firing pin impressions, and extractor marks. The results of our six queries against the RBID indicate that a reference ballistics image database of new guns is currently fraught with too many difficulties to be an effective and efficient law enforcement tool.  相似文献   
995.
Today in modern times, traumatic injuries caused by crossbows are a rarity. The largest collection of cases so far is presented in this study, consisting of four fatalities (two homicides and two suicides) and two non-fatal injuries (grievous bodily harm and an accident). All the victims were male having an age between 31 and 54. The weapons, which were used, were mainly high-performance precision crossbows with telescopic sights and hunting bolts. The parts of the body involved were the facial/head area in three of the cases and the thorax in three of them. There were either deep or total penetration injuries to the cranium and thorax with the bolt remaining in the wound in four out of six cases. The persons with non-fatal crossbow injuries exhibited comparatively few symptoms, despite the sometimes extensive involvement of the interior of the cranium (cerebrocranial penetration, in one instance). The two cases of suicide favoured the body areas often found with gun-users. The aetiological classification of crossbow injuries may be difficult after the removal of the bolt. The external morphology is strongly dependent on the type of tip used. Multiple-bladed hunting broadheads produce radiating incised wounds, whereas conical field tips produce circular to slitlike defects. Correspondingly, the external injuries can be reminiscent of the effects of a violent attack by sharp force or of a gunshot wound. The possibility, supported by clinical data, that the victim might have the ability to act or even to survive for a period of time, even with penetration of the brain, should be taken into account when the cause of death is being investigated.  相似文献   
996.
An alleged assault was reported by a 42-year-old female, with initial medical examination revealing an apparent bite mark on the right buttock. Odontological examination, including visual assessment, full history and photographs showed that the injury did not meet the class characteristics of a human bite. Subsequent digital overlay production showed that the injury pattern was consistent with a corrugated bottle top. This case highlights the need for careful assessment of injuries alleged to be caused by human teeth.  相似文献   
997.
Fatal monointoxications with benzodiazepines, for instance with a suicidal intention, are exceptional findings. We report the autopsy case of an 82-year-old woman who died due to a suicidal monointoxication with Rohypnol 1 mg film tablets (therapeutical agent: flunitrazepam). 0.065 mg/L flunitrazepam and 0.34 mg/L 7-aminoflunitrazepam were detected in a postmortem heart blood sample and toxicological analysis revealed the metabolite 7-aminoflunitrazepam in gastric contents, too. At external examination, a bluish-turquoise coloration was seen around the woman's right nostril and within the oral cavity. At autopsy, similar coloration phenomena were seen on the mucosa of the distal esophagus and the stomach. Formerly, bluish stains on mouth and nostrils were considered indicative of intoxications with organophosphates such as parathion (E 605). More recently, case reports accumulate where an intoxication with Rohypnol 1 film tablets (containing the coloring agent indigocarmine in its core) have to be considered as a potential differential diagnosis of such coloration phenomena.  相似文献   
998.
The frequency of electric arc accidents has been successfully reduced owing to preventive measures taken by the professional association. However, the risk of accidents has continued to exist in private setting. Three fatal electric arc accidents caused by high voltage are reported with reference to the autopsy findings.  相似文献   
999.
In previous investigations hair analysis for ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEE) proved to be suitable for the detection of excessive alcohol consumption. The aim of this study was to compare EtG and FAEE concentrations in hair of alcoholics, social drinkers and teetotallers. Hair samples from 10 alcoholics in withdrawal treatment, 11 fatalities with documented excessive alcohol consumption, four moderate social drinkers who consumed up to 20 g ethanol per day, and three strict teetotallers were analysed. After external degreasing with n-heptane, extraction with a dimethyl sulfoxide/n-heptane mixture and headspace solid-phase microextraction of the extracts, four fatty acid ethyl esters (FAEEs) (ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate) were analysed by gas chromatography-mass spectrometry (GC-MS) with deuterated internal standards. EtG was determined by GC-MS/NCI after ultrasonication of the samples with H2O, cleanup by SPE with aminopropyl columns and PFP derivatisation. The following concentrations were measured for the four groups: teetotallers EtG < 0.002 ng/mg, FAEE 0.05-0.37 ng/mg, moderate social drinkers EtG < 0.002 ng/mg, FAEE 0.26-0.50 ng/mg, alcoholic patients EtG 0.030-0.415 ng/mg, FAEE 0.65-20.50 ng/mg and the fatalities with alcohol history EtG 0.072-3.380 ng/mg, FAEE 1.30-30.60 ng/mg. The results confirm that by using a cut-off value of the sum of FAEE > 1 ng/mg and/or a positive EtG result in hair, excessive alcohol consumption can be identified using hair analysis. However, no significant correlation between the EtG and FAEE concentrations in the positive cases could be shown. Segmental analysis of some of the specimens did not reveal the same distribution for EtG compared to FAEE in hair, and no chronological accordance compared to the self-reported alcohol consumption could be observed for both parameters. These different results of both methods are discussed in terms of differences between EtG and FAEE in mechanism of formation and incorporation into hair and elimination from hair.  相似文献   
1000.
The procedure used in this laboratory for removing and identifying contamination of hair specimens with drugs is demonstrated by its application to hair contaminated by various experimental models. The models include soaking; coating with drug followed by sweat conditions for 6 h; and soaking in a very high concentration of cocaine followed by storage and multiple shampoo treatments. A multi-part wash procedure along with a wash criterion is applied to all samples containing drug above the cutoff. The failure of the wash criterion is a signal that the sample may be positive due to contamination rather than use, and in the absence of other over-riding evidence, the sample would be considered to be negative for drug use. This Wash Criterion has also been tested with hair from subjects demonstrated to be drug users by one or more drug-positive urines; in these studies, all hair samples from demonstrated users passed the Wash Criterion test.  相似文献   
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