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AIM: Postmortem brain studies offer enormous opportunities to study molecular mechanisms associated with suicide. In the present study, conventional [35S]GTPγS binding assay and its version-up method ([35S]GTPγS binding/immunoprecipitation assay) were applied to postmortem human hippocampal membranes prepared from suicide victims and control subjects. METHODS: By using conventional [35S]GTPγS binding assay, functional activations of Gi/o proteins coupled with multiple GPCRs (5-HT1A receptor, α2A-adrenoceptor, M2/M4 mAChRs, adenosine A1 receptor, histamine H3 receptor, group II mGlu, GABAB receptor, µ-opioid receptor, δ-opioid receptor, and NOP receptor) were detected by using 15 different agonists. Furthermore, 5-HT2A receptor- and M1 mAChR-mediated Gαq/11 activation and adenosine A1 receptor-mediated Gαi-3 activation were detectable by means of [35S]GTPγS binding/immunoprecipitation assay. RESULTS: No significant differences in pharmacological parameters of all concentration-response curves investigated were found between suicide victims and control subjects. Significant correlations were obtained for the maximal percent increases between some distinct signaling pathways. CONCLUSION: Although only preliminary and auxiliary results were obtained as to the potential differences between suicide victims and control subjects because of the limited number of subjects as well as unmatched age and postmortem delay, adenosine A1 receptor-mediated Gαi/o activation and 5-HT2A receptor-mediated Gαq/11 activation appear worth focusing on in the future investigations. This study also indicates the possibility that some distinct signaling pathways are interrelated with each other, for example, functional activations of Gi/o proteins coupled to M2/M4 mAChR and 5-HT1A receptor, NOP receptor, and GABAB receptor, and NOP receptor and δ-opioid receptor.
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This article explores the potential of photon-counting computed tomography (CT) in forensic medicine for a range of forensic applications. Photon-counting CT surpasses conventional CT in several key areas. It boasts superior spatial and contrast resolution, enhanced image quality at low x-ray energies, and spectral imaging capabilities that enable more precise material differentiation. These advantages translate to superior visualization of bone structures, foreign bodies, and soft tissues in postmortem examinations. The article discusses the technical principles of photon-counting CT detectors and highlights its potential applications in forensic imaging, including high-resolution virtual autopsies, pediatric forensic CT, trauma analysis, and bone density measurements. Furthermore, advancements in vascular imaging and soft tissue contrast promise to propel CT-based death investigations to an even more prominent role. The article concludes by emphasizing the immense potential of this new technology in forensic medicine and anthropology.
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Lethal intoxications can only very rarely be recognized during an external examination of corpses, as poisoning does not leave any characteristic findings on the deceased. The present study is a retrospective review on 2,4-dinitrophenol (2,4-DNP) intoxications in human subjects from the beginning of the 20th century until today, as well as a case report on a fatal intoxication of a 50-year old obese man in Rostock (Germany) and an introduction for toxicological analysis in post-mortem specimens of the substance ingested in these rare cases. Via selective literature search, the information on occurrence and localization of abnormal pathomorphological external and/or internal findings in cases of 2,4-DNP ingestion/ intoxication was gathered. By 2021, a total of 13 case reports with information on morphological findings due to 2,4-DNP ingestion/intoxication were found. The external findings were dominated by yellowing of the skin, followed by exanthemas/rashes and yellowing of the sclera. The internal findings included yellowing of the internal organs, yellow color of the stomach contents, yellowing of the mucous membranes and an intense yellow color of the urine. Yellowish discoloration of the skin, sclera, mucous membranes, internal organs, sweat and/or an intensive yellow discoloration of the urine are not observed in every 2,4-DNP intoxication. However, when they do occur, they are a characteristic indication of 2,4-DNP ingestion and, if localized to the skin, indicate prolonged consumption. A fatal case from Rostock in 2016 due to prolonged intake of 2,4-DNP for weight loss is exemplified. A simple, fast and cost-effective workup combined with HPLC-DAD for post-mortem toxicology ultimately delivers reliable analysis results.
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BACKGROUND: Pulmonary complications commonly cause mortality in critically ill patients with acute and chronic liver diseases in the intensive care unit. Pneumonia is the most common clinical diagnosis supported by radiological and microbiological results, which are subjective and often with poor yield. The study aimed to correlate clinical diagnosis and postmortem lung histology in patients with liver disease with respiratory failure. METHODS: Records of acute and chronic liver disease patients with respiratory failure-associated mortality and postmortem lung biopsy from September 2009 to March 2020 were analyzed. Clinical diagnosis supported by radiological and/or microbiological data was compared with histology. RESULTS: One hundred eight patients (age 46.83±12.96 years), males 80 (74.1%), 63 (58.3%) cirrhosis of the liver, 30 (27.8%) acute-on-chronic-liver-failure, and 9 (8.3%) acute liver failure, were analyzed. Of the 76 patients (70.37 % of the total) with pneumonia, 33 (43.4 %) had histological evidence of pneumonia. Other histological diagnoses in these patients were normal or nonspecific changes in 27 (35.5 %) and alveolar hemorrhage in 13 (17.1 %). In the remaining 32 patients, histological diagnosis of pneumonia was evident in nine patients (28.1%). Using postmortem histology as the gold standard, the sensitivity, specificity, positive predictive value, and negative predictive value for clinical diagnosis of pneumonia were found to be 78.57%, 34.85%, 43.42%, and 71.88% respectively. The kappa statistics for agreement between the two was 0.12 (95% C.I. -0.04 to 0.27) suggesting poor agreement. Age and histological pneumonia predicted significant missed diagnosis. CONCLUSION: There is poor agreement between clinical diagnosis and postmortem histology. Postmortem lung biopsy helps with the unexplained cause of death.
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BACKGROUND: Determining the postmortem interval (PMI) accurately remains a significant challenge in forensic sciences, especially for intervals greater than 5 years (late PMI). Traditional methods often fail due to the extensive degradation of soft tissues, necessitating reliance on bone material examinations. The precision in estimating PMIs diminishes with time, particularly for intervals between 1 and 5 years, dropping to about 50% accuracy. This study aims to address this issue by identifying key protein biomarkers through proteomics and machine learning, ultimately enhancing the accuracy of PMI estimation for intervals exceeding 15 years. METHODS: Proteomic analysis was conducted using LC-MS/MS on skeletal remains, specifically focusing on the tibia and ribs. Protein identification was performed using two strategies: a tryptic-specific search and a semitryptic search, the latter being particularly beneficial in cases of natural protein degradation. The Random Forest algorithm was used to model protein abundance data, enabling the prediction of PMI. A thorough screening process, combining importance scores and SHAP values, was employed to identify the most informative proteins for model's training and accuracy. RESULTS: A minimal set of three biomarkers-K1C13, PGS1, and CO3A1-was identified, significantly improving the prediction accuracy between PMIs of 15 and 20 years. The model, based on protein abundance data from semitryptic peptides in tibia samples, achieved sustained 100% accuracy across 100 iterations. In contrast, non-supervised methods like PCA and MCA did not yield comparable results. Additionally, the use of semitryptic peptides outperformed tryptic peptides, particularly in tibia proteomes, suggesting their potential reliability in late PMI prediction. CONCLUSIONS: Despite limitations such as sample size and PMI range, this study demonstrates the feasibility of combining proteomics and machine learning for accurate late PMI predictions. Future research should focus on broader PMI ranges and various bone types to further refine and standardize forensic proteomic methodologies for PMI estimation.
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Biomarcadores , Aprendizado de Máquina , Mudanças Depois da Morte , Proteômica , Humanos , Proteômica/métodos , Projetos Piloto , Biomarcadores/análise , Masculino , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Feminino , Pessoa de Meia-Idade , Idoso , Fatores de Tempo , Restos Mortais/química , Tíbia/química , Osso e Ossos/química , Osso e Ossos/metabolismo , Adulto , Idoso de 80 Anos ou maisRESUMO
Advanced characterization is paramount to understanding battery cycling and degradation in greater detail. Herein, we present a novel methodology of battery electrode analysis, employing focused ion beam (FIB) secondary-ion mass spectrometry platforms coupled with a specific lift-out specimen preparation, allowing us to optimize analysis and prevent air contamination. Correlative microscopy, combining electron microscopy and chemical imaging of a liquid electrolyte Li-ion battery electrode, is performed over the entire electrode thickness down to subparticle domains. We observed a distinctive remnant lithiation among interparticles of the anode at the discharge state. Furthermore, chemical mapping reveals the nanometric architecture of advanced composite active materials with a lateral resolution of 16 nm and the presence of a solid electrolyte interface on the particle boundaries. We highlight the methodological advantages of studying interfaces and the ability to conduct high-performance chemical and morphological correlative analyses of battery materials and comment on their potential use in other fields.
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INTRODUCTION: Analysis of a single tooth and nail can provide valuable forensic information, including year of birth, year of death, age, sex, DNA-profile, geographic residence during childhood and at time of death and drug exposure. The aim is to minimize the amount of used bodily material and to validate the applicability of a multidisciplinary sampling protocol. METHODS: A nail of the big toe, a tooth and blood of seven deceased individuals were collected postmortem. Collected materials were sampled and segmented in accordance with the multidisciplinary sampling protocol. DNA analysis was conducted on the pulp of the tooth, isotope analysis (Sr, Pb, O and C) on the enamel and 14C-, toxicological and tooth cementum annulation analysis on root segments. DNA-, isotope (Sr, Pb, O and C) -, toxicological-, and 14C -analysis were conducted on toenail segments. The acquired DNA profiles were compared with profiles acquired from blood. RESULTS: Material from seven deceased persons was analysed. 45 out of 56 analyses on dental samples were successful, constituting a success rate of 80%. Additionally, 27 out of 35 analyses were successful on nail samples, yielding a success rate of 77%. DNA-, toxicological and 14C- analyses performed better in nail than in tooth. Isotope analyses performed better in tooth than in nail. A profile with personal characteristics was constructed and matched for 62% of parameters with collected medical information. CONCLUSION: The performed sampling protocol for simultaneous multidisciplinary forensic analysis on a single tooth and nail sample provided applicable results and valuable information.
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Aims: The aim of this study is to provide a retrospective assessment of the possibility of determining the severity of atherosclerosis based on postmortem computed tomography (PMCT), autopsy protocols and histopathological examination results. In the first stage of the study, 200 cases were evaluated of persons over 40 years of age in whom postmortem computed tomography and autopsy were performed. In the second stage, the cases were divided into a study group (cardiovascular deaths) and a control group, as well as divided by age and, in addition to autopsy protocols and PMCT results, histopathological findings were evaluated. Results: The results of stage I demonstrated that the best detection of atherosclerosis was in the advanced stage with a predominance of detection in PMCT. Atherosclerosis detection in autopsy was highest in the coronary arteries, aorta and cerebral arteries; while in PMCT it remained equal in all evaluated locations. Autopsy showed higher detection of advanced atherosclerotic lesions in the coronary arteries and aorta compared to PMCT. The results of stage II of the study revealed that attaching the results of the general histopathological examination to the retrospective evaluation does not provide an opportunity to increase the accuracy of the evaluation of atherosclerotic lesions. The results obtained indicate the need for prospective studies. Conclusions: Autopsy allows macroscopic evaluation of a very broad spectrum of atherosclerotic lesions, but often without precise determination of their nature, and with limited localization; PMCT allows accurate and reproducible evaluation of calcified atherosclerotic lesions in large and medium-sized vessels, but is unsuitable for the evaluation of non-calcified lesions and small vessels; targeted histopathological examinations allow very accurate, but local assessment of atherosclerotic lesions.
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Aterosclerose , Autopsia , Tomografia Computadorizada por Raios X , Humanos , Autopsia/métodos , Feminino , Masculino , Aterosclerose/patologia , Aterosclerose/diagnóstico por imagem , Estudos Retrospectivos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Patologia Legal/métodos , Adulto , Vasos Coronários/patologia , Vasos Coronários/diagnóstico por imagem , Idoso , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Causas de Morte , Imageamento post mortemRESUMO
Mathematical algorithms known as "epigenetic clocks" use methylation values at a set of CpG sites to estimate the biological age of an individual in a tissue-specific manner. These clocks have demonstrated both acceleration and delays in epigenetic aging in multiple neuropsychiatric conditions, including schizophrenia and neurodevelopmental disorders such as autism spectrum disorder. However, no study to date has examined epigenetic aging in ADHD despite its status as one of the most prevalent neurodevelopmental conditions, with 1 in 9 children having ever received an ADHD diagnosis in the US. Only a handful of studies have examined epigenetic age in brain tissue from neurodevelopmental conditions, with none focused on ADHD, despite the obvious relevance to pathogenesis. Thus, here we asked if post-mortem brain tissue in those with lifetime histories of ADHD would show accelerated or delayed epigenetic age, as has been found for other neurodevelopmental conditions. We applied four different epigenetic clocks to estimate epigenetic age in individuals with ADHD and unaffected controls from cortical (anterior cingulate cortex, N = 55) and striatal (caudate, N = 56) post-mortem brain tissue, as well as peripheral blood (N = 84) and saliva (N = 112). After determining which epigenetic clock performed best in each tissue, we asked if ADHD was associated with altered biological aging in corticostriatal brain and peripheral tissues. We found that a range of epigenetic clocks accurately predicted chronological age in all tissues. We also found that a diagnosis of ADHD was not significantly associated with differential epigenetic aging, neither for the postmortem ACC or caudate, nor for peripheral tissues. These findings held when accounting for comorbid psychiatric diagnoses, substance use, and stimulant medication. Thus, in this study of epigenetic clocks in ADHD, we find no evidence of altered epigenetic aging in corticostriatal brain regions nor in peripheral tissue. We consider reasons for this unexpected finding, including the limited sampling of brain regions, the age range of individuals studied, and the possibility that processes that accelerate epigenetic age may be counteracted by the developmental delay posited in some models of ADHD.
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OBJECTIVE: To develop and implement an online application for the numerical method of determination of the postmortem interval and its limiting faults, caused by errors of measurement processes, based on the Marshall-Hoare law of cooling and dual thermometry of the corpse's core. MATERIAL AND METHODS: The numerical search for a minimum of two variables' target function, obtained from the system of non-linear Marshall-Hoare equations, reflecting the dual thermometry of the corpse's core was performed. The code of online program was written in Python 3 programming language. RESULTS: The method for determination of the postmortem interval, based on iterative algorithm of non-linear optimization, allowing by dual thermometry of the corpse to consider the uniqueness of its cooling conditions, as well as to calculate the degree of uncertainty of computational estimations, caused by the impact of measurement errors, has been developed. The method is implemented in the format of the Warm Bodies Z online application. CONCLUSIONS: The developed numerical method and its online application are recommended for determining of the postmortem interval.
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Mudanças Depois da Morte , Humanos , Algoritmos , Patologia Legal/métodos , Autopsia/métodos , Temperatura CorporalRESUMO
Diphenhydramine has been available for decades in non-prescription formulations for the treatment of allergic reactions, insomnia and symptomology associated with colds. In addition, dimenhydrinate, a precursor to diphenhydramine, is available in preparations for the treatment of nausea and vomiting. Diphenhydramine and other first-generation antihistamines are being replaced by second- and third-generation antihistamines which are associated with fewer side effects, notably the lack of drowsiness; however, there are still a variety of therapeutic uses that have persisted in both adults and children. In this study, postmortem blood concentrations of diphenhydramine were determined, by liquid chromatography tandem mass spectrometry, in seven children with concentrations ranging from 0.051 to 2.6 mg/L. The cause of death in two cases was attributed, at least in part, to diphenhydramine toxicity while diphenhydramine detection in five cases was considered incidental to the cause of death.
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CLINICAL PROBLEM: Detection of manual strangulation, choking and hanging, as well as the intensity of these actions, helps to clarify the course of events, to enforce the state's right to prosecute and ultimately to protect against further attacks. However, this is complicated by the scarcity of externally visible findings. STANDARD PROCEDURE TO DATE: The forensic examination of the head and neck after strangulation is carried out by means of external inspection to detect injuries and congestion above the strangulation level. Lesions below the surface of the skin, in particular of the subcutaneous fat tissue, the muscles or the laryngeal structures, usually escape the external inspection. FORENSIC RADIOLOGY AS AN IMPORTANT COMPONENT: Imaging techniques allow internal injuries to be recorded and objectified, which can be of considerable added value in the collection of evidence. Since criminal proceedings must meet the highest standards of security, high demands are placed on imaging and diagnosis. ASSESSMENT: Imaging techniques are suitable for detecting and objectifying internal injuries after a person has survived strangulation. However, their excellent reconstruction and visualization capabilities also make them a valuable addition to postmortem examinations. RECOMMENDATIONS FOR PRACTICE: After reported and survived strangulation, choking or hanging, magnetic resonance imaging (MRI) of the soft tissues of the neck should be performed as soon as possible, and if cerebral damage is suspected, the skull should also be examined. If the event was not survived, whole-body computed tomography (CT) is now standard practice at many forensic medicine institutes.
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Asfixia , Lesões do Pescoço , Humanos , Lesões do Pescoço/diagnóstico , Lesões do Pescoço/diagnóstico por imagem , Asfixia/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Obstrução das Vias Respiratórias/diagnóstico por imagem , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/diagnóstico , Medicina Legal/métodosRESUMO
Fentanyl and its analogues are synthetic opioids of varying potencies that are unfortunately heavily abused. Over the last 15 years, fentanyl and its analogues have contributed to the increasing prominence of hospitalisation and numerous deaths due to drug overdose. In this comprehensive literature review, the mechanism of toxicity of the drug in humans is evaluated. A systematic approach was used whereby the relevant literature has been detailed where the toxicity of fentanyl and/or its analogues to different organs/systems were investigated. Furthermore, the review covers the post-mortem toxicological data and demographic information from past fatal cases where fentanyl was believed to be involved. Such insight into fentanyl toxicity is useful as an aid to better understand the toxic doses of the drug and the suspected mechanism of action and the unexpected complications associated with overdose incidences involving the drug. Finally, the review offers an overview of the traditional and emerging test systems used to investigate the adverse effects of fentanyl on human health.
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The estimation of the postmortem interval (PMI) is a significant challenge in legal medicine and forensic sciences due to the dynamic and continuous decomposition of organisms after death. Thanatochemistry has emerged as a promising area to estimate PMI by measuring the concentrations of postmortem biochemical markers. This systematic review and meta-analysis aimed to summarize evidence on postmortem biochemical alterations in vitreous humor (VH) and synovial fluid (SF) to estimate early PMI. Comprehensive searches of electronic databases identified studies measuring postmortem biomarker concentrations in both matrices. Our analysis included three meta-analytical approaches: calculating standardized mean differences to assess variations in biochemical parameters, executing correlation meta-analysis (ρ) to explore relationships between these parameters and PMI, and conducting meta-regression to derive a predictive model. Results from five eligible studies indicated no correlation between sodium levels and PMI in both matrices. However, a strong correlation was found between potassium levels and PMI in VH (ρ = 0.69; 95 % CI 0.52 to 0.86) and SF (ρ = 0.81; 95 % CI 0.75 to 0.87), with the meta-regression yielding the optimal predictive equation for SF: [K+] = 6.15 + 0.21 × PMI. These findings support the use of potassium as a reliable biomarker for PMI estimation, particularly in SF.
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Post-mortem computed tomography (PMCT) is a useful tool to investigate the cause of death. To appropriately use PMCT for cause-of-death analysis, it is necessary to know natural courses after death such as hypostasis in the lungs. We aimed to investigate the natural time-course change of postmortem chest CT findings and its pathological correlation in piglets. Serial chest PMCT scans of four piglets were performed each hour for 24 h and the chronological changes of the lung were evaluated. Immediately after the final CT scan, the autopsy was conducted and bilateral lungs were taken for pathological examination. Two additional piglets were sacrificed and pathological specimens were prepared immediately after death for reference. On pulmonary PMCT, ground glass attenuation (GGA) appeared after the first several hours and increased gradually. Histologically, GGA corresponded to pulmonary edema. The time-related increase in CT attenuation was more prominent in the dorsal lung. Consolidation, endotracheal air defects, and pleural effusion were not observed on PMCT. GGA appeared after the first several hours and increased gradually, and it corresponded to pulmonary edema. GGA in the lung as one of the natural postmortem processes needs to be distinguished from pathogenic findings depending on the time elapsed since death. J. Med. Invest. 71 : 232-236, August, 2024.
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Mudanças Depois da Morte , Tomografia Computadorizada por Raios X , Animais , Suínos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Autopsia , Edema Pulmonar/diagnóstico por imagem , Edema Pulmonar/patologiaRESUMO
In this study, we explored the correlation between the lysosome-mitochondrial apoptosis pathway and fish softening, as well as the correlation between ferritin degradation and lysosomal iron changes. The results indicated that ferritin levels gradually decreased, lysosomal iron first increased and then decreased and tended to stabilize, and lysosomal membrane stability significantly decreased (p < 0.05). Spearman's analysis suggested that an increase in lysosomal iron was associated with ferritin degradation. Lysosomal instability promoted the release of cathepsin D, thereby increasing the release of Bid and Bax, and inhibiting the expression of Bcl-2. Subsequently, caspase-9/-3 was activated. In addition, transmission electron microscopy revealed ultrastructural damage to mitochondria and cell nuclei, which are morphological features of apoptosis during post-mortem storage. Moreover, TUNEL staining confirmed the occurrence of apoptosis. We concluded that the lysosome- mitochondrial apoptosis pathway was active during the storage of Esox Lucius, in which ferritin degradation and increased lysosomal iron were key factors inducing lysosomal damage, and cathepsin D released by lysosomes was a key factor connecting lysosomes and mitochondria.
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OBJECTIVE: To determine the diagnostic accuracy of virtual autopsy using whole-body postmortem ultra-high field magnetic resonance imaging (MRI) at 7 Tesla (T), using a short T2-weighted imaging (T2-WI) protocol, compared with classical autopsy, for detecting structural abnormalities in small second-trimester fetuses. METHODS: Thirty consecutive fetuses at 13-19 weeks' gestation (weight, 17-364 g) were included following spontaneous pregnancy loss or termination of pregnancy. After fixation in 10% formaldehyde solution (48 h to 1 week), all fetuses were scanned using a two-dimensional turbo high-resolution T2-WI protocol with multislice relaxation time, followed by an invasive autopsy. The diagnostic accuracy of virtual autopsy vs classical autopsy was calculated for 990 anatomical structures (30 fetuses × 33 items). Sensitivity, specificity, positive and negative predictive values and Cohen's κ coefficient of agreement, with their 95% CIs, as well as the McNemar test, were used to evaluate the accuracy and agreement of the two diagnostic methods. Analysis was stratified by anatomical segment (nervous, pulmonary, cardiovascular, digestive, renal, facial and skeletal) and across three gestational-age intervals (13-14, 15-16 and 17-19 weeks). RESULTS: Considering classical autopsy as the gold standard, virtual autopsy had a sensitivity of 92.04% (95% CI, 85.42-96.29%) and a specificity of 97.87% (95% CI, 94.64-99.42%), with a positive predictive value of 96.30% (95% CI, 90.78-98.56%) and a negative predictive value of 95.34% (95% CI, 91.61-97.45%), achieving a diagnostic accuracy of 95.68% (95% CI, 92.73-97.68%) for detecting structural abnormalities in second-trimester fetuses. Cohen's κ for virtual vs classical autopsy was 0.907. The diagnostic ability of virtual autopsy at 7 T for malformed fetuses was superior to that of classical autopsy for analyzing the nervous system in small fetuses with pronounced autolysis, equivalent to that of classical autopsy when analyzing pulmonary, cardiovascular and renal systems and inferior when evaluating the fetal intestines. The sensitivity of virtual autopsy at 7 T for describing structural abnormalities increased with gestational age. CONCLUSION: Virtual fetal autopsy using 7-T MRI and a turbo high-resolution T2-WI protocol with multislice relaxation time is a feasible postmortem diagnostic tool for the identification of fetal structural anomalies. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
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An extensive proteomic analysis utilizing the tandem mass tag (TMT) method was conducted to investigate the changes in protein expression in the longissimus dorsi muscle of Xinjiang goats over various post-mortem intervals: immediately after death within 0 h, 12 h, 24 h and 48 h. The investigation carefully identified around 108 proteins that showed significant changes in expression during these intervals. Among these proteins, six were highlighted for their crucial roles in muscle growth and differentiation of muscle fibers post-mortem. These proteins, namely COL12A1, MRPL46, CTNNB1, MYH1, CAPZA1, and MYL9, have a direct effect on the meat's quality attributes, such as tenderness and color. Further discuss observed a progressive increase in the expression of proteins linked with oxidative metabolism (MSRB2, ENOX1, LOC102170282, GSTM1, and AOC3) as the post-mortem aging period extended, particularly between 24 h to 48 h. These proteins are instrumental in defining the color and flavor profiles of goat meat, underscoring the importance of precise processing and storage conditions to preserve meat quality during the critical aging phase. This enhanced understanding of protein expression dynamics offers significant implications for optimizing meat quality and provides a scientific basis for post-mortem handling practices in the goat meat industry.
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The estimation of the postmortem interval for skeletal remains is a crucial aspect of forensic anthropology. This paper illustrates the importance of radiocarbon analysis for establishing medico-legal significance and supporting forensic identification, through the analysis of three case studies for which the years of both birth and death were investigated. In Audresselles, Northern France, a partial skull was discovered with no contextual information or identity. Radiocarbon dating yielded an average calibrated calendar age of 4232 BCE (92.5% probability), indicating significant archaeological value but no forensic relevance. In the second case, skeletal remains were found in the flooded underground of a historical fort at Wimereux, Northern France, also with no identity. Radiocarbon dating based on the bomb-pulse curve indicated a calibrated date of death in 1962 CE (37.3% probability) or 1974-1975 CE (58.1% probability), both surpassing the French statute of limitations. Lastly, a skeleton with a suspected identity was discovered near Valenciennes, Northern France, and various biological tissues underwent radiocarbon dating. A bone sample suggested a calibrated date of death of 1998-2002 CE (84.6% probability), differing from a hair sample (2013-2018 CE, 83.3% probability) because of the slower bone tissue remodeling process. DNA analysis confirmed the person's identity, reported missing a decade prior to the discovery of the remains, following the alignment of the radiocarbon results with the individual's year of birth based on dental tissues and year of death. These case studies reveal that traditional radiocarbon dating and bomb-pulse dating are essential tools for estimating the postmortem interval, providing mutual benefits for archaeologists, forensic anthropologists, and the criminal justice system. Key points: Traditional radiocarbon dating and bomb-pulse dating are essential tools to establish the archaeological relevance or medico-legal significance of human skeletal remains.Bomb-pulse dating enables assessment of an individual's years of birth and death.Bomb-pulse dating helps to narrow down the pool of candidates for identification.Radiocarbon analysis provides mutual benefits for archaeologists, forensic anthropologists, and the criminal justice system.
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This study investigated if microscopic surface features captured with a scanning electron microscope (SEM) effectively discriminate fracture timing. We hypothesized that microscopic fracture characteristics, including delamination, osteon pullout, and microcracks, may vary as bone elasticity decreases, elucidating perimortem and postmortem events more reliably than macroscopic analyses. Thirty-seven unembalmed, defleshed human femoral shafts from males (n=18) and females (n=2) aged 33-81 years were fractured at experimentally simulated postmortem intervals (PMIs) ranging from 1 to 60 warm weather days (250-40,600 ADH). A gravity convection oven was used to approximate tissue decomposition at 37â¯C and 27â¯C, and the resulting heat-time unit (accumulated degree hours, or ADH) was used to examine fractures in elastic/wet versus brittle/dry bone. The bones were fractured with a drop test frame using a three-point bending setup, sensors were used to calculate fracture energy, and high-speed photography documented fracture events. The following data were collected to relate fracture appearance to the biomechanical properties of bone: PMI (postmortem interval) length in ADH, temperature, humidity, collagen percentage, water loss, bone mineral density, cortical bone thickness, fracture energy, age, sex, cause of death, and microscopic fracture feature scores. SEM micrographs were collected from the primary tension zones of each fracture surface, and three microscopic fracture characteristics were scored from a region of interest in the center of the tension zone: percentage of delaminated osteons, percent osteon pullout, and number of microcracks. Multiple linear regression showed that microscopic fracture surface features are strong predictors of ADH (adjusted R-squared=0.67 for the 0 - 40,000 ADH samples; adjusted R-squared=0.92 for the 0-16,000 ADH samples). Osteon pullout is the single best predictor of ADH. Additionally, water loss is the primary driver of bone elasticity changes in low ADH samples, while collagen fibers appear to remain intact until later in the postmortem interval (approximately 40,000 ADH in this study). The results of this study indicate microscopic fracture surface analysis detects the biomechanical effects of decreased elasticity more reliably and with greater sensitivity than macroscopic analysis.