Estimation of postmortem interval using histological and oxidative biomarkers in human bone marrow.

In forensic medicine, estimating the postmortem interval (PMI) is of great importance for the timeline and the reconstruction of the events surrounding death. Bone marrow (BM) is one of the largest organs in the body, with good resistance to autolysis and contamination. Therefore, the present study aims to correlate different postmortem intervals and bone marrow antioxidant enzyme levels using an Enzyme-linked immunosorbent assay (ELISA). In addition, detection of the changes in the histological structure of human bone marrow in relation to the time passed since death. BM samples from 20 forensic autopsy cadavers were obtained from cases referred to the Department of Forensic Medicine in the Ministry of Justice, Dakahlia Governorate, processed for histopathological examination as well as estimation of reduced glutathione (GSH), glutathione peroxidase (GPX), and glutathione reductase (GRX) using ELISA. Results of ELISA analysis showed a significant decrease in the level of antioxidant enzymes with increasing PMI; regarding histopathological examination, from 6 to > 18 h PMI, the changes in morphology after death were gradual, progressive, and regular, indicating great value in PMI determination. Also, 18 h of PMI showed loss of cellular details, absence of fat cells, and necrosis of BM with the nucleus dispersed as eosinophilic debris. Estimation of antioxidant enzymes level in human bone marrow using ELISA and detection of the changes in the histological structure of human bone marrow in relation to time passed since the death, either separately or in combination, can be used to estimate PMI accurately.

Estimation of postmortem interval in myocardial stab wounds and firearm injuries: An immunohistochemical comparative study using C5b-9 and cardiac Troponin C.

BACKGROUND: Estimation of postmortem interval (PMI) is a critical component of forensic death investigations. C5b-9 and cardiac Troponin C (cTnC) have the potential as markers for myocardial damage and can be suitable markers for determination of PMI. The aim of current study was to estimate different postmortem intervals using C5b-9 and cTnC detected by immunohistochemical technique in stab wounds and firearm injuries of the heart. MATERIALS AND METHODS: Cardiac tissue samples from 70 forensic autopsy cadavers were obtained from XXXXXXX morgue, processed, for histopathological examination as well as immunohistochemical detection of C5b-9 and cTnC expression. The surface area of the positive C5b-9 and troponin C immune reactive cardiac tissue was measured morphometrically then the data were used to construct multiple regression equations for the estimation of PMI. RESULTS: Histopathological autolytic changes occurred in all groups and increased in intensity with the increase in the PMI in stab wound and firearm injury groups. These findings were supported by immunohistochemical morphometric analysis. Constructed equations to estimate PMI were highly accurate especially those combining both markers. CONCLUSION: C5b-9 and cTnC can be considered reliable indicators of myocardial damage and can be used either separately or in combination for accurate estimation of PMI.

Psychological distress among Egyptian physicians during COVID-19 pandemic.

OBJECTIVE: The current study's main objective was to measure the prevalence of psychological distress and its associated factors among Egyptian physicians during the COVID-19 pandemic. Perceived stressors and coping strategies were also explored. METHODS: A cross-sectional study on 714 physicians was carried out using an online administered questionnaire. The questionnaire included sociodemographic and occupational data, data related to the current pandemic, Kessler psychological distress scale, and the brief resilient coping scale. Multivariable logistic regression analysis was performed to identify significant predictors. RESULTS: About 50% of physicians had severe psychological distress. Among studied physicians, the significant predictors were being female, having a pre-existing illness, having an elderly family member, and being in close contact with a case (AOR 1.6, 1.6, 1.4 and 1.7, respectively). Meanwhile, significant occupational predictors were less experienced and frontline physicians (AOR 2.0 and 1.8, respectively). The most distressful concern was fear for families and personal health and safety, while religious coping was the most effective coping strategy. CONCLUSION: During the current pandemic, Egyptian physicians have a high prevalence of psychological distress. Frontline, low-experienced, female, previously ill physicians are more likely to have severe psychological distress. Therefore, psychological preparedness and psychological support services should be implemented and made easily accessible during pandemics.

Time course analysis of large-scale gene expression in incised muscle using correspondence analysis.

Studying the time course of gene expression in injured skeletal muscle would help to estimate the timing of injuries. In this study, we investigated large-scale gene expression in incision-injured mouse skeletal muscle by DNA microarray using correspondence analysis (CA). Biceps femoris muscle samples were collected 6, 12, and 24 hours after injury, and RNA was extracted and prepared for microarray analysis. On a 2-dimensional plot by CA, the genes (row score coordinate) located farther from each time series (column score coordinate) had more upregulation at particular times. Each gene was situated in 6 subdivided triangular areas according to the magnitude of the relationship of the fold change (FC) value at each time point compared to the control. In each area, genes for which the ratios of two particular FC values were close to 1 were distributed along the two border lines. There was a tendency for genes whose FC values were almost equal to be distributed near the intersection of these 6 areas. Therefore, the gene marker candidates for estimation of the timing of injuries were detectable according to the location on the CA plot. Moreover, gene sets created by a specific gene and its surrounding genes were composed of genes that showed similar or identical fluctuation patterns to the specific gene. In various analyses on these sets, significant gene ontology term and pathway activity may reflect changes in specific genes. In conclusion, analyses of gene sets based on CA plots is effective for investigation of the time-dependent fluctuation in gene expression after injury.

Time-Dependent Changes in Local and Serum Levels of Inflammatory Cytokines as Markers for Incised Wound Aging of Skeletal Muscles.

Wound age estimation is an important research field in forensic pathology. The expression levels of cytokines in the incised skeletal muscle were analyzed using a mouse model to explore the applicability for wound aging. A 5-mm long incisional wound was made at the biceps femoris muscle, and the muscle and serum were sampled at 6, 12, 24 and 48 hours after injury. Using a multiplex bead-based immunoassay, we measured the tissue levels of nine cytokines (IL-1ß, IL-6, IL-7, CCL2, CCL3, CCL4, CXCL1, CXCL2, and CXCL10), which are all involved in the pathways of inflammatory response and tissue injury. Immunoassay of post-injury muscle samples revealed significant increases in the levels of six cytokines, except for CCL3, CCL4 and IL-7, at 6 hours after injury. The elevated tissue levels of these six cytokines were maintained during 48 hours after injury, although the levels of IL-6 and CXCL1 were significantly decreased at 12 hours. In case of CCL3, its tissue levels were increased only at 12 hours. By contrast, CCL4 and IL-7 levels were increased only at 48 hours. Moreover, serum levels of most cytokines, except for CXCL1, remained unchanged during 24 hours after injury, followed by significant increases at 48 hours. Serum CXCL1 levels were increased at 6 hours and then decreased to the basal levels. Thus, the significant increase in the muscle levels of CXCL1 and IL-7 was observed at 6 and 48 hours after injury, respectively. Measuring muscle CXCL1 and IL-7 levels is helpful for estimating incised wound aging.

A simple method for calculating the likelihood ratio in a kinship test using X-chromosomal markers incorporating linkage, linkage disequilibrium, and mutation.

X-chromosomal short tandem repeats (X-STRs) are useful for personal identification and kinship tests. However, it has not yet been fully established how to incorporate linkage and linkage disequilibrium (LD) into the calculation of the likelihood ratio (LR). In this paper, we describe a simple calculation method of LR for X-STRs that incorporated linkage, LD, and mutations. Initially, Japanese population data of 27 X-STRs (DXS6807, DXS9902, DXS6795, DXS6810, DXS10076, DXS10077, DXS10078, DXS10162, DXS10163, DXS10164, DXS7132, DXS981, DXS6800, DXS6803, DXS6809, DXS6789, DXS6799, DXS7424, DXS101, DXS7133, GATA172D05, DXS10103, HPRTB, GATA31E08, DXS8377, DXS10147, and DXS7423) were collected from 748 unrelated individuals to estimate the influence of LD. Significant LD was observed on six pairs of loci. Subsequently, using the population data, a simulation study was performed to evaluate the validity of the present calculation method for LR in cases of father-daughter, full-sisters, paternal half-sisters, maternal half-sisters, and unrelated pairs of females (FD, FS, PHS, MHS, and UR, respectively). As a result, the distribution of LR among FD was completely separated from that among UR. In the sibship test, 98.6% of FS and 98.0% of PHS surpassed the maximum value of UR in combined LR. Even in the FS versus MHS setting, 60.5% of FS had a higher LR than any MHS. We conclude that the present model is powerful in discriminating the relationship and is able to obtain a reasonable LR with fewer computations.

Sudden Death in an Adult Due to Nontraumatic Diaphragmatic Hernia.

Sudden death due to diaphragmatic hernia in an adult is exceptionally rare. A 43-year-old man was found dead by his cohabiting mother, lying supine on the floor in his house. He had complained of epigastric discomfort for 1 month, and respiratory symptoms occurred 1 day before his death. He had no history of trauma. Postmortem computed tomography scan revealed the enlarged fluid-filled stomach herniated into the left pleural cavity, compressing the left lung with a mediastinal shift to the right. At autopsy, the left pleural cavity was occupied by herniated abdominal contents with mediastinal shift. The herniation of the stomach, the whole spleen, a portion of the colon, and omentum into the left pleural cavity had occurred through a smooth oval 9 × 5-cm defect in the posterolateral part of the light diaphragm. The stomach was markedly distended and contained 1600 mL of yellowish brown liquid with food residue. Ischemic changes of the herniated organs were not observed. Death was attributed to respiratory failure from abdominal viscera herniation into the left pleural cavity.