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901.
During STR analysis on the 310 Genetic Analyzer, retarded migration of GS500ROX size standards and alleles in some samples was observed. The contribution of reagents, capillary and performance optimized polymer POP 4 to the observed anomaly was experimentally eliminated. Variation in electrophoresis temperature between 55 degrees C and 65 degrees C did not alter the rate of migration of GX500ROX size standard and sample alleles. An eroded connector for the cathode mounted on the heat plate assembly caused the abnormal migration. Hence, it is important to verify the mobility of all fragments in the size standard for each sample to avoid any erroneous allele calls by the automated data analysis software. 相似文献
902.
Loss of heterozygosity detected in a short tandem repeat (STR) locus commonly used for human DNA identification 总被引:3,自引:0,他引:3
Rubocki RJ Duffy KJ Shepard KL McCue BJ Shepherd SJ Wisecarver JL 《Journal of forensic sciences》2000,45(5):1087-1089
Short tandem repeat (STR) markers are commonly used in basic genetic research and in human identification testing. Clinically, STRs can be used to study genetic alterations in tumors. A genetic deletion common to many types of cancer is referred to as the loss of heterozygosity (LOH). Numerous examples of LOH in cancer have been described and some have been mapped to areas located in close proximity to markers employed in human identity testing. Despite this fact, LOH has rarely been observed for STR loci commonly employed in forensic testing. Recently, for medico-legal purposes, we were asked to determine whether a tissue biopsy originated from a particular individual. For a reference source we assessed two specimens, one from normal tissue and one from cancerous tissue. When both reference specimens were used to generate DNA profiles, we observed LOH at one STR locus, D13S317. As demonstrated in other cancers only the cancerous biopsy demonstrated LOH. The forensic community should be cognizant of these unusual circumstances because, as identification of human DNA continues to be used more extensively, certain instances will arise in which reference material will not be readily available. In these situations, archived specimens may be employed as a reference source. Clinical specimens such as tissue biopsies should be used with caution if they have not been confirmed to contain normal tissue. 相似文献
903.
Marc B Baudry F Douceron H Ghaith A Wepierre JL Garnier M 《Journal of forensic sciences》2000,45(1):216-222
Three cases of suicide by electrocution with low-voltage current were observed in five years (1994-1998) by medical clinical forensic examiners of an Emergency Forensic Unit of the Paris suburb among 2,000 external death examinations. The cases involved one woman, aged 72 and two men, aged 38 and 41. In the last two cases, electric burns were retrieved under bared electric wires, placed on the arms or fingers in order to realize a hand-to-hand electric circuit involving the heart muscle. In the other case, the electric circuit between mouth and foot also involved the heart muscle. Household low-voltage current delivered (220 V in France) had a sufficient strength to induce local muscular paralysis and heart fibrillation. In the three cases, blood samples taken have retrieved very high levels of muscular enzymes (CPK, LDH) correlated to the mechanism of electric death. The rareness of suicide by electrocution and its forensic characteristics are detailed in order to help the clinical forensic examiners, prosecutors, and police officers concerned by such death examinations. 相似文献
904.
Drug abuse and its consequences are everyday problems encountered globally, and Scotland is no exception. During a study of drug-related deaths in the Strathclyde region of Scotland it was noted that known drug users who had recently been released from prison were at high risk of dying from a drug overdose. The majority of deaths occurred within one week of the release date and polydrug use was prevalent. Morphine was the most frequently encountered drug and this was found in combination with benzodiazepines in a significant number of cases. This paper highlights the dangers of resuming drug consumption following a period of abstinence. 相似文献
905.
906.
Advances in the diagnosis of wound vitality: a review 总被引:2,自引:0,他引:2
Hernández-Cueto C Girela E Sweet DJ 《The American journal of forensic medicine and pathology》2000,21(1):21-31
The diagnosis of the vital origin of wounds in many cases remains an unsolved problem for the forensic pathologist. Practical experience enables the expert to diagnose the vital or postmortem origin of wounds on the basis of macroscopic examination. In some cases, optic microscopy is used to confirm the diagnosis. In many other cases, additional more sensitive and specific markers of vitality are required. In the past 50 years, comprehensive research on this topic has resulted in a better understanding of the acute inflammatory reaction. The development and application of sensitive and specific markers through research in the areas of histochemistry, enzymology, and biochemistry has provided a partial solution to the problems involved in wound vitality diagnosis. A review of this challenging area of forensic pathology, including an explanation of these methods and markers, is presented in this paper. 相似文献
907.
Determining the cause of death when a restrained person suddenly dies is a problem for death investigators. Twenty-one cases of death during prone restraint are reported as examples of the common elements and range of variation in these apparently asphyxial events. A reasonable diagnosis of restraint asphyxia can usually be made after ruling out other causes and collecting supportive participant and witness statements in a timely fashion. Common elements in this syndrome include prone restraint with pressure on the upper torso; handcuffing, leg restraint, or hogtying; acute psychosis and agitation, often stimulant drug induced; physical exertion and struggle; and obesity. Establishing a temporal association between the restraint and the sudden loss of consciousness/death is critical to making a correct determination of cause of death. 相似文献
908.
Campman SC Holmes JF Sokolove PE Romero JA Yost BA Lie JT 《The American journal of forensic medicine and pathology》2000,21(1):69-73
Arterial fibromuscular dysplasia (FMD) represents a collection of noninflammatory and nonatherosclerotic vascular diseases with a poorly understood etiology. Classically occurring in renal and cerebral arteries, this entity has also been reported in coronary, carotid, and other medium and small arteries. One case occurring in the pulmonary vasculature has been reported. Fatal hemothorax and lung hemorrhage have multiple causes, including other vascular malformations and connective tissue disorders; however, cases of pulmonary FMD are exceedingly rare. We report what appears to be the second such association, occurring in a 69-year-old man. The patient presented with a 3-week history of increasing dyspnea, fatigue, and productive cough; 3 days of increasing back and chest pain; and syncope. Chest radiograph showed a "white-out" of the left lung. The patient died shortly after admission from a fulminant respiratory disease of undetermined etiology. At autopsy he was found to have a massive left hemothorax resulting from an unsuspected pulmonary arterial fibromuscular dysplasia. 相似文献
909.
Byard RW Green H James RA Gilbert JD 《The American journal of forensic medicine and pathology》2000,21(2):101-106
A retrospective analysis of 68 cases of fatal childhood pedestrian accidents in South Australia that occurred over a 20-year period from January 1977 to December 1996 was undertaken. The age range was 12 months to 16 years (average, 7.6 years), with a male to female ratio of 41:27. The most common site of significant injury was the head (91.2%), followed by the abdomen (50%), chest (47.1%), and neck (38.2%). The most frequently encountered significant injury combinations involved the head, chest, and abdomen (14.7%); the head and chest (11.8%); and the head, neck, and abdomen (11.8%). Injuries were severe, consisting of extensive compound and comminuted skull fractures, neck fractures, and massive intraparenchymal brain and internal organ damage with avulsions and fragmentation. Non-life-threatening limb injuries occurred in 88% of cases. A distinct subgroup involved infants and younger children playing in driveways at home who were hit by reversing vehicles. The injuries were often of such a severe nature that death was instantaneous and with no possibility of successful medical intervention. More deaths occurred during the winter than summer months. 相似文献
910.
Olanzapine is an antipsychotic drug that has been on the market since 1996. Olanzapine-related deaths are very rare; the literature reports only one. However, in a recent 5-month period one medical examiner's office found two such cases that are reported in this paper. One is a suicide and the other is not. The toxicologic and anatomic findings for each are described. Blood olanzapine concentrations ranged from 0.237 microg/ml for one to 0.675 microg/ml for the other. Gastric content concentrations also exhibited a wide range, varying from 0.197 microg/ml to 17.400 microg/ml for the other. Distribution studies of the liver, kidney, and brain produced nondetectable concentrations for the drug. There were no consistent pathologic anatomic findings for cause of death except for moderate coronary atherosclerosis in the nonsuicide case. Both deaths were attributed to olanzapine toxicity. 相似文献