Junyao Lv

Haplotype diversity of 22 Y-chromosomal STRs in a southeast China population sample (Chaoshan area)

In this study, 22 Y-specific STR loci (DYS19, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438, DYS439, DYS461, DYS481, DYS504, DYS505, DYS508, DYS533, DYS576, DYS588, DYS607, DYS634, and DYS643) were analyzed in 216 unrelated male individuals from southeast China (Chaoshan area) by three multiplex PCR systems. The haplotype diversity using the classical set of Y-STRs (DYS19, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, and DYS385; PowerPlexY Systems) was 0.9908. For the same population sample, the haplotype diversity using the new sets of 11 novel Y-STRs (DYS461, DYS481, DYS504, DYS505, DYS508, DYS533, DYS576, DYS588, DYS607, DYS634, and DYS643; multiplex I and II) was 0.9917. By combining the allelic states of the 22 Y-STR loci we could construct highly informative haplotypes that allowed the discrimination of 99.1% (214 out of 216) of the samples tested and the overall haplotype diversity of 0.9999. These results, including the haplotype data at 22 Y-STR loci in the present study, provide useful information for forensic practice in the Chaoshan population in southeast China.

Time of Death Revealed by Hydrocarbons of Empty Puparia of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae): A Field Experiment

Determination of the postmortem interval (PMI) is crucial for investigating homicide. However, there are currently only limited methods available. Especially, once the PMI exceeds the duration of pre-adult development of the flies with the adult emergence, its determination is very approximate. Herein, we report the regular changes in hydrocarbon composition during the weathering process of the puparia in the field in Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae), one of the common species of necrophagous flies. Correlation analysis showed that the relative abundance of nearly all of the branched alkanes and alkenes decreased significantly with the weathering time. Especially, for 9 of the peaks, over 88% of the variance in their abundance was explained by weathering time. Further analysis indicated that the regular changes caused mainly by the different weathering rates of various hydrocarbons. Additionally, the weathering rates were found to depend on the chemical structure and molecular weight of the hydrocarbons. These results indicate strongly that hydrocarbon analysis is a powerful tool for determining the weathering time of the necrophagous fly puparia, and is expected to markedly improve the determination of the late PMI.

Analysis of Blood Trace Elements and Biochemical Indexes Levels in Severe Craniocerebral Trauma Adults with Glasgow Coma Scale and Injury Severity Score

We aimed to investigate the correlation between the Glasgow Coma Scale (GCS), the injury severity score (ISS) and serum levels of trace elements (TE) in severe trauma patients to analyze alteration of the levels of trace elements and serum biochemical indexes in the period of admission from 126 adult cases of severe brain trauma with traffic accidents. Multi-trace elements for patients in the trauma-TE groups were used. The results indicated that all patients presented an acute trace elements deficiency syndrome (ATEDs) after severe trauma, and the correlation between ISS and serum levels of Fe, Zn, and Mg was significant. Compared to the normal control group, levels of the trace elements in serum were significantly decreased after trauma, suggesting that enhancement of immunity to infection and multiple organ failure (MOF) via the monitoring and supplement of trace elements will be a good strategy to severe traumatic patients in clinics.

Severe Diffuse Axon Injury in Chronic Alcoholic Rat Medulla Oblongata Following a Concussion Blow

AIMS We investigated the axonal morphological changes and expression of both tau protein and β-APP following concussion to the medulla oblongata, in a rat model of chronic alcoholism. METHODS Fifty-nine male Sprague-Dawley rats were randomly divided into EtOH, EtOH-TBI and control groups (water group, water-TBI group). To establish chronic alcoholic rats, rats were intragastrically given edible spirituous liquor twice daily. Rats also received a blow on the occipital tuberosity with an iron pendulum. Morphological changes and expression of tau and β-APP proteins in the medulla oblongata were examined. RESULTS (a) Nerve fibre thickening and twisting were observed in alcoholic rats, with nerve fibre changes becoming more significant following a concussion blow, which leads to some nerve fibres fracturing. (b) Transmission electron microscopy revealed that the nerve fibre myelin became loosened and displayed lamellar separation, which became more significant following concussion. (c) The integral optical density (IOD) sum value of β-APP of the EtOH-TBI group was lower than that in the EtOH group (P < 0.05); the Tau IOD sum value of the EtOH-TBI group was higher than that in the EtOH group (P < 0.05). CONCLUSION (a) Chronic alcoholism caused nerve fibre and neuronal morphology damage in the rat medulla oblongata, with structural damage becoming more significant following concussion. (b) Concussion changed the expression of β-APP and tau protein in chronic alcoholic rat medulla oblongata, suggesting that chronic alcoholism can lead to severe axonal injury following a concussion blow. (c) The effect of chronic alcoholism may be synergistic the concussion blow to promote animal injury and death.

Metabolic Characterization of Myocardial Infarction Using GC-MS-Based Tissue Metabolomics

Understanding the metabolic features of myocardial infarction (MI) is critical to its prevention and treatment. Here, we aimed to characterize the metabolic features of early MI using a tissue metabolomics method based on gas chromatography-mass spectrometry (GC-MS). Thirty-four pairs of infarcted myocardia and their matched non-infarcted myocardia were collected from 34 rats that underwent coronary artery ligation (CAL); their metabolic profiles were compared by GC-MS-based tissue metabolomics to characterize the metabolic features of MI. On the basis of differential metabolites, their diagnostic potential for MI was analyzed, and MI-related metabolic pathways were investigated. Serum samples before and post MI were used to validate the results obtained in myocardia. The metabolic profile of the infarcted myocardia was obviously different from that of the non-infarcted myocardia, as indicated by partial least squares discriminate analysis (PLS-DA) plots. Twenty-two metabolites were identified to be different between the infarcted myocardia and non-infarcted myocardia. These metabolic alterations reflect energy deficit, acidosis, oxidative stress, ionic imbalance, and cardiac injury post MI. Glutamine, glutamate, and lactate were confirmed to jointly confer a favorable potential for diagnosing MI, which can be well validated in serum.

The densities of visceral organs and the extent of pathologic changes.

In this study, we designed a new device to measure the density of internal organs and correlated with their pathologic changes. The densities of hearts, livers, lungs and brains from 169 autopsy cases were measured with different extent of pathologic changes by an integrated volume-density meter. All samples were divided into 2 groups: intact and pathologic groups. The extent of pathologic changes was classified into 3 stages: slight edema, intermediate edema, severe edema (or severe fatty degeneration only for livers) according to the histologic features. Results show that there were significant differences between each subgroup and intact group and the density was closely correlated with pathologic changes. Therefore, the external parameter of density might offer some clues to its pathologic changes, such as edema and fatty changes.

Serum lipid feature and potential biomarkers of lethal ventricular tachyarrhythmia (LVTA) induced by myocardial ion channel diseases: a rat model study.

To determine the cause of death in myocardial ion channel diseases (MICD)-induced sudden cardiac death (SCD) cases is a difficulty in forensic identification practices. The majority of MICD-induced SCD cases would experience lethal ventricular tachyarrhythmia (LVTA) before deaths; thus, confirming the occurrence of LVTA in bodies can offer a key evidence to identify these cases. Several lipids in the myocardia were found disturbed after LVTA; yet, whether serum lipidome would be disrupted by LVTA is not clear. Therefore, we aimed to screen lipid feature and related diagnostic markers of LVTA in serum here. An aconitine-induced LVTA-SCD rat model was produced. Blood samples before LVTA and immediately after LVTA were retrieved and related serum specimens were used for ultra-performance liquid chromatography-mass spectrometry (UPLC-MS)-based lipidomics analyses. On the basis of the defined differential lipids, a lipid-related metabolic pathway network was constructed and potential biomarkers were screened. Twelve aconitine-induced LVTA rats were produced. Totally, 188 lipids in serum were disrupted during the LVTA-SCD process, which belong to 11 lipid classes. Most of the differential lipids were correlated, suggesting that they were interacted and that the changes were holistic during LVTA process. Ten lipid pathways were activated during LVTA process; the main lipid classes involved in these pathways were ceramide, sphingomyelin, phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine. Phosphatidylcholine O-40:4, sphingomyelin d46:5, and phosphatidylethanolamine 40:4 were tested as potential diagnostic markers of LVTA-SCD event in serum. The current results indicate a substantial change in serum lipidome after LVTA-SCD; lipidomics holds promise to identify MICD-induced SCDs in forensic practices.

Anterior wrist and medial malleolus as the novel sites of tissue selection: a retrospective study on electric shock death through the hand-to-foot circuit pathway

Our previous work demonstrated that characteristic changes could occur in the anterior wrist and medial malleolus in electric deaths through the hand-to-foot electric circuit pathway in an electric shock rat model. However, whether the same phenomenon occurs in humans is unknown. The aim of the present retrospective study was to ascertain whether the anterior wrist and medial malleolus could also be selected as the promising and significant sites in electric death through the hand-to-foot circuit pathway. Nineteen human cases from the autopsy and one clinical survivor who sustained a severe electric shock through the hand-to-foot circuit pathway were analyzed. Additional ten autopsy patients who died from traffic accidents and sudden cardiac attacks were used as the control group. Histopathological changes in the soft tissues of the anterior wrist and medial malleolus in all autopsy patients, as well as the electric current pathway of the survivor, were observed. The results showed that the nuclear polarizations in the anterior wrist and medial malleolus soft tissues of the electric death were extremely noticeable as compared with the controls. The most severe electrical injury in the survivor occurred in the anterior wrist. These findings suggest that the soft tissues of the anterior wrist and/or the medial malleolus as the narrowest parts of the limbs could be used as the complementary sites for tissue selection and considered as necessary locations for examinations to assess the electric death in medicolegal identification.

Intramedullary schwannoma of the upper cervical spinal cord: a case study of identification in pathologic autopsy

ABSTRACT Intramedullary schwannoma of the upper cervical spinal cord is rarely reported in forensic medicine. We herein report a case involving a patient who died of compression from an intramedullary schwannoma in the upper cervical spinal cord. A 30-year-old man initially presented with a five-day history of pain in the left chest that progressed to weakening in the left arm. Although the patient was treated with analgesic poultices, he developed inspiratory dyspnoea and died while working the next day without having undergone any medical imaging examination or surgical treatment. Anatomical and histopathological examinations revealed an intramedullary schwannoma in the left cervical spinal cord (C3–C5) underneath the spinal nerve root. The cause of death might have been asphyxia secondary to the tumour, which interfered with the nerve function in the respiratory muscles. This finding suggests that an autopsy is essential for pathologists and medicolegists to comprehensively undertake their due obligation to obtain “the first evidence”, especially when there is a lack of directly related evidence. As part of the central nervous system, the spinal cord could be systematically included in a routine pathological autopsy in some cases.