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841.
Adrienne E. Ng B.S. Ernesto Sandoval B.S. Terence M. Murphy Ph.D. 《Journal of forensic sciences》2016,61(Z1):S226-S229
Lophophora williamsii (peyote) is a small, spineless, greenish‐blue cactus found in Mexico and the southwestern United States. Ingestion of the cactus can result in hallucinations due to its content of mescaline. In the United States, L. williamsii is classified as a Schedule I controlled substance. In this study, we use DNA analysis of the chloroplast trnL/trnF region and chloroplast rbcL gene to identify the individuals of Lophophora. Using the rbcL gene, Lophophora specimens could be distinguished from outgroups, but species within the genus could not be distinguished. The trnL/trnF region split the Lophophora genus into several groups based on the length and substructure of an AT‐rich segment of the sequence. Our results indicate that the genetic variability at the trnL/trnF locus is greater than previously recognized. Although DNA structures at the trnL/trnF region and rbcL gene do not align with the classification of Lophophora species, they can be used to aid in forensic analysis. 相似文献
842.
Alper Gümüş M.D. Burak Gümüş M.D. Erdal Özer M.D. Esma Yücetaş M.D. Uğur Yücetaş M.D. Emin Düz M.D. Soner Sarı M.D. Macit Koldaş M.D. 《Journal of forensic sciences》2016,61(Z1):S144-S149
The aim of our study was to investigate the postmortem levels of glucose and glycogen in hepatic, renal, muscle, and brain tissues and then examine the changes in those levels that could be useful for estimating postmortem interval. We established an animal model. Seventy female BALB/c albino mice were used in this study. After being sacrificed, the mice were randomly divided into six groups according to time elapsed since death (Group 1: 0 h; Group 2: 12 h; Group 3: 24 h; Group 4: 36 h; Group 5: 48 h; and Group 6: 60 h). Glucose levels were significantly different between groups for all tissues studied. Slope of the change per unit time was higher for the hepatic glucose levels. Based on these results, it is possible to estimate postmortem interval using postmortem glucose levels in hepatic tissue. Tissue‐specific assessment may contribute valuable information to postmortem interval studies. 相似文献
843.
Calvin Y. Shiroma D.M.D. 《Journal of forensic sciences》2016,61(1):59-67
During the Korean War, the Office of the Quartermaster General's Graves Registration Service (GRS) was responsible for the recovery, processing, identification, and repatriation of US remains. In January 1951, the GRS established a Central Identification Unit (CIU) at Kokura, Japan. At the Kokura CIU, postmortem dental examinations were performed by the dental technicians. Thirty‐nine postmortem dental examinations performed at the CIU were compared to the findings documented in the Forensic Odontology Reports written at the JPAC Central Identification Laboratory (CIL). Differences were noted in 20 comparisons (51%). The majority of the discrepancies was considered negligible and would not alter the JPAC decision to disinter a set of unknown remains. Charting discrepancies that were considered significant included the occasional failure of the Kokura technicians to identify teeth with inter‐proximal or esthetic restorations and the misidentification of a mechanically prepared tooth (i.e., tooth prepared for a restoration) as a carious surface. 相似文献
844.
Sachil Kumar M.Sc. Wahid Ali Ph.D. Uma S. Singh M.D. Ashutosh Kumar M.D. Sandeep Bhattacharya M.D. Anoop K. Verma M.D. Raja Rupani M.D. 《Journal of forensic sciences》2016,61(Z1):S241-S245
Estimation of time of death is an indispensible requirement of every medico‐legal autopsy, but unfortunately, there is not a single method by which it could be determined accurately. This study focused on the temperature‐dependent postmortem degradation of cardiac troponin‐T and its association with postmortem interval (PMI) in human. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS‐PAGE), and visualization by Western blot using cTnT‐specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc (Universal Hood). The results indicate a characteristic banding pattern among human cadavers (n = 6) and a pseudo‐linear relationship between percentage of cTnT degradation and the log of the time since death (r > 0.95), which can be used to estimate the postmortem interval. The data presented demonstrate that this technique can provide an extended time range during which PMI can be more accurately estimated. 相似文献
845.
Michael A. Marino M.S. Brandy Voyer B.S. Robert B. Cody Ph.D. A. John Dane Ph.D. Mercurio Veltri Pharm.D. Ling Huang Ph.D. 《Journal of forensic sciences》2016,61(Z1):S82-S91
The usage of herbal incenses containing synthetic cannabinoids has caused an increase in medical incidents and triggered legislations to ban these products throughout the world. Law enforcement agencies are experiencing sample backlogs due to the variety of the products and the addition of new and still‐legal compounds. In our study, proton nuclear magnetic resonance (NMR) spectroscopy was employed to promptly screen the synthetic cannabinoids after their rapid, direct detection on the herbs and in the powders by direct analysis in real time mass spectrometry (DART‐MS). A simple sample preparation protocol was employed on 50 mg of herbal sample matrices for quick NMR detection. Ten synthetic cannabinoids were discovered in fifteen herbal incenses. The combined DART‐MS and NMR methods can be used to quickly screen synthetic cannabinoids in powder and herbal samples, serving as a complementary approach to conventional GC‐MS or LC‐MS methods. 相似文献
846.
Suicide by shotgun is a common method of suicide with high regional variation. We sought to describe their distinct, challenging features and provide demographic and risk characteristics. We reviewed 228 gunshot wounds autopsied at Mayo Clinic from 1994 to 2014; of these, 75 (32.9%) were shotgun wounds. All were suicides and contact range. Ages ranged from 14 to 92 years old; of these, 97% were men. The majority involved the head (70.9%), were intraoral (48.2%), and had upward (73.2%) and backward (73.2%) directionality. Next most common was the chest (21.5%), with backward (94.1%) and downward (64.7%) directionality. Four involved multiple wounds. Wadding was recovered in 16 (21.3%) cases. Six (8.0%) had a survival period. Most (66.7%) took place at home. Seventy‐one percent had a known psychiatric history; 32.4% had positive toxicology. Although contact range shotgun wounds cause severe destruction, entrance wound and other characteristic are identifiable with thorough scene, autopsy, and radiographic documentation. 相似文献
847.
848.
A finding in the autopsy of John Paul Jones, the American Revolutionary War naval hero, may explain his terminal illness. During his last 2 years, he had a persistent productive cough and dyspnea. Ten days before death, he developed rapidly progressive dependent edema and ascites. He died in France in 1792. His body, preserved in alcohol in a lead coffin, was, in 1905, removed to the United States. Glomerulonephritis was noted on an autopsy, performed in France, but there was no comment then or since about ventricular wall thickness being the same in both ventricles at 5–6 mm. Hypertrophy and dilatation with biventricular failure followed by tissue shrinkage during 113 years in alcohol could have resulted in these ventricular wall findings. Systemic hypertension and left ventricular failure are consistent with his respiratory symptoms complicated perhaps by pulmonary emboli, right ventricular failure with tricuspid regurgitation, peripheral congestion, and jaundice. 相似文献
849.
Cynthia M. Cale B.S. Madison E. Earll M.S. Krista E. Latham Ph.D. Gay L. Bush Ph.D. 《Journal of forensic sciences》2016,61(1):196-203
The occurrence of secondary DNA transfer has been previously established. However, the transfer of DNA through an intermediary has not been revisited with more sensitive current technologies implemented to increase the likelihood of obtaining results from low‐template/low‐quality samples. This study evaluated whether this increased sensitivity could lead to the detection of interpretable secondary DNA transfer profiles. After two minutes of hand to hand contact, participants immediately handled assigned knives. Swabbings of the knives with detectable amounts of DNA were amplified with the Identifiler® Plus Amplification Kit and injected on a 3130xl. DNA typing results indicated that secondary DNA transfer was detected in 85% of the samples. In five samples, the secondary contributor was either the only contributor or the major contributor identified despite never coming into direct contact with the knife. This study demonstrates the risk of assuming that DNA recovered from an object resulted from direct contact. 相似文献
850.
Marek Dziadosz Ph.D. Michael Klintschar Prof. M.D. Jörg Teske Ph.D. 《Journal of forensic sciences》2016,61(Z1):S250-S251
This study highlights the problem of levamisole‐adulterated cocaine in context of active traffic participation. For the purposes of levamisole concentration monitoring in human serum, an analytical method based on LC‐MS/MS and solid‐phase extraction was applied. A Luna 5 μm C18 (2) 100 A, 150 mm × 2 mm column and a mobile phase consisting of A (H2O/methanol = 95/5, v/v) and B (H2O/methanol = 3/97, v/v), both with 10 mM ammonium acetate and with 0.1% acetic acid (pH = 3.2), were used. The validation experiments demonstrated that the method applied was appropriate for levamisole quantification in human serum. For 23% of levamisole‐positive samples, the concentrations exceeded 20 ng/mL. Therefore, the interaction of this drug with cocaine has to be considered as important for active traffic participation. As a consequence, monitoring of levamisole concentration in human serum is recommended, as long as it is used as cocaine adulterant. 相似文献