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841.
Application of mRNA Expression Analysis to Human Blood Identification in Degenerated Samples that were False‐negative by Immunochromatography,, 下载免费PDF全文
Shusaku Matsumura M.S. Aya Matsusue Ph.D. Brian Waters M.S. Masayuki Kashiwagi M.D. Ph.D. Kenji Hara Ph.D. Shin‐ichi Kubo M.D. Ph.D. 《Journal of forensic sciences》2016,61(4):903-912
Forensic laboratories are often faced with cases in which methamphetamine hydrochloride‐mixed blood is unable to be identified as human blood by immunochromatography against human hemoglobin A0. The application of mRNA expression analysis to samples that showed a false‐negative with immunochromatography was investigated as an alternative approach that did not depend on the antigen–antibody reaction. Real‐time PCR was used to examine the expression levels of blood markers such as glycophorin A, spectrin beta, and hemoglobin beta. Hemoglobin beta was the only marker that was specifically detected in blood, while glycophorin A was useful for determining human specificity. Hemoglobin beta showed good detection sensitivity and was detectable in 37‐year‐old blood stains. Hemoglobin beta was exclusively detectable in methamphetamine hydrochloride‐mixed blood stains. Detergents and disinfectants did not significantly influence mRNA markers. The proposed mRNA expression analysis was suitable for human blood identification as an alternative method to immunochromatography. 相似文献
842.
Samah F. Ibrahim M.D. Marwa Issak M.D. Amany A. Bayoumy M.D. Dina S. Abd El‐Fatah M.D. 《Journal of forensic sciences》2016,61(4):1007-1010
Wound age estimation is one of the most important forensic aspects. Troponin I (TnI) and many cytokines, for example, tissue plasminogen activator (tPA), are involved in wound inflammation and healing. Skeletal (TnI) and cutaneous (tPA) mRNA was detected using real‐time PCR in 25 female albino rats. They were divided into 5 groups: control and 4 injured groups. Injured groups were sacrificed 1, 6, 24, and 30 h after inflicting contused wound. The expression levels of cutaneous (tPA) were decreased significantly at 1, 6, and 30 h after contusion (71.7%, 30.7 and 16.9%), while the expression levels of skeletal (TnI) were increased significantly at 1 and 6 h post‐traumatic, then they gradually decreased until reaching normal levels at 24 h and assumed significantly lower levels at 30 h postcontusion. These results suggested that the determination of cutaneous (tPA) and skeletal (TnI) mRNA levels was useful for wound age estimation. 相似文献
843.
Developmental Times of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) at Constant Temperatures and Applications in Forensic Entomology 下载免费PDF全文
Yong‐qiang Yang M.D. Xue‐bo Li M.D. Ru‐yue Shao M.D. Zhou Lyu M.D. Hong‐wei Li M.D. Gen‐ping Li M.D. Lyu‐zi Xu M.M. Li‐hua Wan B.M. 《Journal of forensic sciences》2016,61(5):1278-1284
The characteristic life stages of infesting blowflies (Calliphoridae) such as Chrysomya megacephala (Fabricius) are powerful evidence for estimating the death time of a corpse, but an established reference of developmental times for local blowfly species is required. We determined the developmental rates of C. megacephala from southwest China at seven constant temperatures (16–34°C). Isomegalen and isomorphen diagrams were constructed based on the larval length and time for each developmental event (first ecdysis, second ecdysis, wandering, pupariation, and eclosion), at each temperature. A thermal summation model was constructed by estimating the developmental threshold temperature D0 and the thermal summation constant K. The thermal summation model indicated that, for complete development from egg hatching to eclosion, D0 = 9.07 ± 0.54°C and K = 3991.07 ± 187.26 h °C. This reference can increase the accuracy of estimations of postmortem intervals in China by predicting the growth of C. megacephala. 相似文献
844.
845.
FORENSIC Autopsy of People Having Committed Suicide in 2002 and in 2012: Comparison of Epidemiological and Sociological Data 下载免费PDF全文
Angélique Franchi M.D. Jacques Bagur M.D. Patrick Lemoine Ph.D. Delphine Maucort‐Boulch Ph.D. Daniel Malicier Ph.D. Géraldine Maujean M.D. 《Journal of forensic sciences》2016,61(1):109-115
This work compares epidemiological and sociological data on persons having committed suicide in 2002 and in 2012 through a retrospective study of every suicide case having led to an autopsy at the Institute for Forensic Medicine of Lyon in 2002 and in 2012. The study included sociodemographic data, medical data, and toxicological data. A total of 486 cases were included (242 cases in 2002 and 244 cases in 2012). People committing suicide were on average older in 2012 than in 2002 with a larger proportion of over 55. There was also an increase in the proportion of psychiatric antecedents (p < 0.001). Whatever the date of death by suicide, the most affected age range is the 45–54. The results highlight the necessity of bolstering the prevention plans, in particular for people over 45. 相似文献
846.
Amanda O. Fisher‐Hubbard M.D. Kilak Kesha M.D. Francisco Diaz M.D. Chantel Njiwaji M.D. PaoLin Chi M.D. Carl J. Schmidt M.D. 《Journal of forensic sciences》2016,61(6):1541-1545
The Valsalva maneuver is used in clinical medicine for the diagnosis and/or treatment of various cardiovascular conditions. It can also be used in activities of daily living, such as defecation. Due to the cardiovascular effects produced during the Valsalva maneuver, it may be contraindicated in certain medical conditions and could be a trigger of sudden cardiac death. The incidence and prevalence of death following Valsalva maneuver in the presence of underlying cardiovascular disease, or “commode cardia,” has not been examined. In 2012, the Wayne County Medical Examiner's Office (Detroit, MI) investigated 21 deaths that occurred on the toilet, fourteen of which were due to cardiovascular disease. In another 31 deaths in the bathroom due to cardiovascular disease, the possibility that the decedent defecated immediately prior to death could not be excluded. Hence, the incidence of commode cardia in this population ranges from 2.3 to 7.4% of all cardiovascular‐related deaths. 相似文献
847.
Molecular Pathology of Pulmonary Edema in Forensic Autopsy Cases with Special Regard to Fatal Methamphetamine Intoxication 下载免费PDF全文
Rui Zhao Ph.D. M.D. Dong Zhao Ph.D. M.D. Ye Xue M.D. Bao‐Li Zhu Ph.D. M.D. Da‐Wei Guan Ph.D. M.D. Xiao‐Li Xie Ph.D. M.D. Qi Wang Ph.D. M.D. 《Journal of forensic sciences》2016,61(6):1531-1537
Pulmonary edema is a common finding in fatal methamphetamine intoxication. However, the underlying mechanism remains poorly understood. This study investigated the molecular pathology of alveolar damage involving pulmonary edema in forensic autopsy cases. Seven candidate reference genes (RPL13A, YWHAZ, GUSB, SDHA, GAPDH, B2M, and ACTB) were evaluated in the lung by the geNorm module in qBaseplus software. RPL13A, YWHAZ, and GUSB were identified as the most stable reference genes. Using these validated reference genes, intrapulmonary mRNA expressions of matrix metalloproteinases (MMPs), intercellular adhesion molecule‐1 (ICAM‐1), claudin‐5 (CLDN‐5), and aquaporins (AQPs) were examined. Relative mRNA quantification using TaqMan real‐time PCR assay demonstrated higher expressions of all markers except for AQP‐5 in fatal METH intoxication cases. These findings suggested alveolar damage and compensatory response in fatal METH intoxication cases. Systematic analysis of gene expressions using real‐time qPCR is a useful tool in forensic death investigation. 相似文献
848.
Josep De Alcaraz‐Fossoul Ph.D. Cristina Mestres Patris B.Sc. Carme Barrot Feixat Ph.D. Luke McGarr B.Sc. Donna Brandelli M.Sc. Karen Stow Ph.D. Manel Gené Badia Ph.D. 《Journal of forensic sciences》2016,61(2):322-333
The authors are exploring degradation patterns of latent fingermarks over time which can be quantitatively determined in a predictable manner by visual means. Several physical degradation parameters for assessing this hypothesis are evaluated. This article analyzes the parameter “minutiae count” as a function of time. Experiment variables included were secretion type (sebaceous‐rich and eccrine‐rich), substrate (glass and plastic), and exposure to light (dark, shade, and direct light). Depositions were sequentially visualized with Titanium Dioxide powder over a period of 6 months, photographed, and number of minutiae recorded. Results revealed a significant decrease of minutiae for eccrine‐rich marks on glass but insignificant for sebaceous‐rich marks on the same surface. However, significant degradation was observed for both types of secretions on plastic. The authors conclude that the distinctive prevalence of minutiae changes over time indicates with a high degree of certainty the hypothesis is valid and deserves additional exploration. 相似文献
849.
Automated Classification of Epiphyses in the Distal Radius and Ulna using a Support Vector Machine 下载免费PDF全文
Ya‐hui Wang M.D. Tai‐ang Liu Ph.D. Hua Wei M.D. Lei Wan M.D. Chong‐liang Ying B.A. Guang‐you Zhu M.D. 《Journal of forensic sciences》2016,61(2):409-414
The aim of this study was to automatically classify epiphyses in the distal radius and ulna using a support vector machine (SVM) and to examine the accuracy of the epiphyseal growth grades generated by the support vector machine. X‐ray images of distal radii and ulnae were collected from 140 Chinese teenagers aged between 11.0 and 19.0 years. Epiphyseal growth of the two elements was classified into five grades. Features of each element were extracted using a histogram of oriented gradient (HOG), and models were established using support vector classification (SVC). The prediction results and the validity of the models were evaluated with a cross‐validation test and independent test for accuracy (PA). Our findings suggest that this new technique for epiphyseal classification was successful and that an automated technique using an SVM is reliable and feasible, with a relative high accuracy for the models. 相似文献
850.