International Journal of Legal Medicine最新文献

Sex determination is a critical step in identification. Scarce studies assessed the sexual dimorphism of specific lumbar vertebrae in Egyptians. This prospective study which enrolled 134 Egyptians assessed the sexual dimorphism of lumbar vertebrae using multi-slice computed tomography. At all levels, six vertebral measurements were investigated, including the upper end plate depth (EPDu), the lower end plate depth (EPDl), the upper end plate width (EPWu), the lower end plate width (EPWl), the anterior height of vertebral body (VBHa) and the posterior height of vertebral body (VBHp). The males exhibited significantly greater measurements than females, and EPDu, EPDl, EPWu, and EPWl of L1, EPDl of L2, EPWu of L3, and EPWl of L4 were the best individual sex predictors. We introduced five sex-predicting models showing exceptional area under curves ≥ 0.9. The models incorporating L1 and L2 measurements showed the highest R² of 0.791 and 0.801, respectively: Log probability of male sex=-51.524 + (5.878 x EPDu L1) + (4.383 x EPWl L1) + (4.309 x VBHp L1) and = -43.971 + (3.057 x EPDu L2) + (3.324 x EPDl L2) + (5.466 x EPWu L2) + (-10.867 x VBHa L2) + (9.699 x VBHp L2). Despite the significant correlations between the age and various measurements at different vertebral levels, lumbar vertebral bodies did not undergo uniform geometric changes with age; instead, specific regions and aspects of vertebral morphology change in distinct, sex-specific ways. We recommend validating the proposed models in different populations to generalize the obtained findings.

Object: The differentiation of acute myocardial infarction (AMI) has long been a challenging problem in clinical diagnosis and forensic identification. Recent studies have shown that microRNAs (miRNAs) in exosomes are involved in the development and progression of AMI. results indicated that plasma exosomal miRNAs can be considered as novel biomarkers for early AMI recognition.

Method: In this study, exosomal miRNAs in plasma associated with the pathogenesis of AMI was explored and AMI identification model based on these miRNAs were established using machine learning technology.

Result: Following the analysis of differentially expressed miRNAs in plasma-derived exosomes, the expression levels of 36 miRNAs increase with the passage of time, including miR-3473, miR-504, miR-490-5p, miR-218a-2-3p, and miR-760-3p, showed an increasing trend over time in the plasma exosomes of AMI rats. Based on machine learning techniques, miR-3473, miR-504, miR-490-5p, miR-218a-2-3p were used to construct a model for recognizing early AMI. The precision of the AMI identification model reached 0.955.

Conclusion: The results indicated that plasma exosomal miRNAs can be considered as novel biomarkers for early AMI recognition.

R-etomidate and metomidate, employed clinically as sedatives and hypnotics in human and veterinary medicine, respectively, have recently gained attention due to their escalating nonmedical use. Owing to their intoxicating effects and addictive potential, illicit abuse of these compounds has surged over the past few years. Understanding the enantiomer ratio of etomidate and metomidate in hair can help identify patterns of abuse and the source of the drugs. Here, a chiral separation and quantification method was developed to analyze etomidate and metomidate enantiomers in human hair. Approximately 20 mg of hair was extracted with acetonitrile by cryogenic grinding and then analyzed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Chromatographic separation was achieved using a Lux 3 μm cellulose-3 chiral column (150 mm × 4.6 mm) under gradient elution. The linearity ranged from 10 to 1000 pg/mg for all compounds. The validated method was applied to 98 authentic hair samples. The enantiomeric ratios of etomidate and metomidate were quantified using the enantiomeric fraction (EF), defined as [R-enantiomer]/[R + S-enantiomers]. The observed EF values spanned 0.40-1.00 for etomidate and 0.49-1.00 for metomidate, indicating variable stereochemical compositions across samples. This study is the first to report the chiral separation and quantification of etomidate and metomidate enantiomers in human hair using UHPLC-MS/MS. Although only R-etomidate is clinically approved, forensic hair analysis identified S-etomidate coexisting with R-enantiomers in 8 samples, indicating nonmedical exposure to incompletely refined or racemic mixtures.

Introduction: Perioperative death is a catastrophic event for the family and the surgical team. It is in the interest of both that an autopsy is carried out to explain the death. We report a sudden perioperative death post aortic valve replacement in an undiagnosed hypertrophic cardiomyopathy (HCM) in an elderly female.

Case report: A 73-year-old female underwent an elective aortic valve replacement (AVR) due to severe aortic valve stenosis (AS). The operation went smoothly. However, left ventricular function was poor despite maximal inotropic treatment. The left ventricular function never recovered and she died on the operating table. The heart weight was normal but the left ventricle shows septal hypertrophy (20 mm). Histology of the left ventricle showed florid myocyte disarray indicating hypertrophic cardiomyopathy.

Discussion: AS is the most common Valvular Heart Disease, and most patients undergo AVR. Nevertheless, sudden unexpected death remains a common cause of late mortality after successful valve replacement. Surprisingly this lady died just after the operative procedure. Histological examination confirmed HCM. HCM is an inherited cardiac condition and it is important for the family to be screened to prevent future sudden cardiac death.

Conclusion: This case highlights the importance of autopsy in a post-operative death case. It can be of great value to the surgical team and family members.

Forensic age estimation is essential for legal and social decision-making when reliable documentation is lacking. Traditionally, ossification of the medial clavicular epiphysis (MCE) is assessed by visual staging, but norm variants frequently limit classic systems and introduce error and irreproducibility. High-resolution computed tomography (CT) allows for quantitative morphometric assessment, potentially offering support - especially in such cases. Based on the approach of Hua et al. (2014) an open-source workflow for metric age estimation of the medial clavicles using semi-automatic three-dimensional (3D) CT segmentation was developed. Clinical CT scans were pseudonymized, archived in XNAT (Extensible Neuroimaging Archive Toolkit), and 3D models were generated in 3D Slicer. Expert-guided segmentation and alignment enabled extraction of quantitative parameters including planar areas and volumes of epiphyses and metaphyses; area and volume ratios were calculated as dimensionless metrics. It was concluded that morphometric assessment of the medial clavicles via 3D imaging is a promising approach for forensic age estimation. The workflow's open-source architecture supports transparency and collaborative validation. Future research should validate metric markers and pursue workflow automation, particularly to address anatomically complex cases.

In this study, 137 pairwise relationships representing four major relationship categories involving 49 Turkish individuals from four families were analyzed to evaluate the potential gain in the statistical power associated with likelihood ratios (LR) when using sequence-based versus length-based genotyping methods over the same STR loci coverage. To this end, the MPS Precision ID GlobalFiler NGS STR panel Kit and CE GlobalFiler™ PCR Amplification Kit were used. MPS-based analysis revealed the presence of 37 STR DNA sequence variations and / or the presence of 26 STR DNA sequence flanking region SNPs compared to the 150 unique alleles obtained with CE-based genotyping. Considering that most kinship LR calculation software do not readily take into consideration STR DNA sequence variants and STR DNA sequence flanking region SNP data that becomes available during MPS-based genotyping, an alphanumeric allele re-coding system was implemented to incorporate such additional STR isoallelic data to the already available allele calls. Over all the four major relationship categories analyzed, a significant increase in the mean combined LR (cLR) was observed when going from CE-based to MPS-based typing, whereby a 78.08 to 7,864,630.60-fold increase was noted. More specifically, in 134 out of the 137 pairwise relationships analyzed, MPS-based cLR values were higher than those calculated using CE-based data. While the mean cLR was >1,000 for three out of the four major relationship categories when using CE, the only exception being the third degree relationships, the mean cLR was >1,000 for all the four major relationship categories when using MPS. Notably, the mean cLR obtained for the third degree relationships was 47.61 with CE and 3,717.31 with MPS. In comparison with CE-based genotyping, when fully taken into account as proposed in the current study, the DNA sequence variation data afforded by MPS-based genotyping led to a statistically significant gain in terms of cLR values obtained. The use of MPS for cLR calculations had the most impact for both the second and third degree relationships, the two complex / distant type analyzed, hence further underscoring the prospects for MPS in kinship analysis. While the current study demonstrated that cLR is likely to increase substantially upon going from CE to MPS genotyping over the same loci coverage for a given case, when the additional DNA sequence variances are also taken into consideration, further increases are expected due to the more diverse type of forensic markers and even wider loci coverages used by MPS kits.

Rapid technological advancements have significantly enhanced DNA analysis. A key innovation is Next-Generation Sequencing (NGS), also known as Massively Parallel Sequencing (MPS), which followed classic Sanger (CS) sequencing. Compared to CS, NGS offers higher sensitivity, resolution, and throughput, making it particularly valuable for mitochondrial DNA (mtDNA) analysis. The high copy number, matrilineal inheritance, and non-recombining nature of mtDNA, especially its hypervariable regions (HV), make it highly relevant in forensic investigations. NGS has introduced streamlined protocols and improved low-level heteroplasmy detection in mtDNA sequencing. However, with any new technology, its informativeness and authenticity must be evaluated against traditional methods. This study compared mitotypes from degraded WWII skeletal remains recovered from a Slovenian mass grave, using the same DNA extraction method to minimize pre-sequencing variability. Femurs were mechanically and chemically cleaned, pulverized, and fully demineralized. DNA was extracted and purified using EZ1 Advanced XL and quantified with an in-house protocol. CS sequencing was performed using BigDye Terminator Kit v1.1 and ABI PRISM™ 3130 Genetic Analyzer, while NGS was conducted with the Precision ID mtDNA Control Region Panel and Ion GeneStudio™ S5 System. Comparison of mitotypes revealed that NGS identified low-level heteroplasmies undetectable by CS, particularly in length heteroplasmy. However, since Ion Torrent™ Suite 5.10.1 is prone to errors, certain NGS variants had to be disregarded.

Detecting gunshot residues (GSR) plays a crucial role in forensic science and forensic medicine by providing important insights into the shooting distance, the shooter, as well as the type of weapon and ammunition used. Detection of GSR on dark surfaces is often impossible on site, and traditional methods such as tape-lift techniques with adhesive films or scanning electron microscope tabs might destroy the GSR pattern at the crime scene during their application. Infrared (IR) photography has proven particularly effective in detecting GSR on dark surfaces, enabling the preservation of the GSR pattern before applying destructive methods. This study aimed to examine how the type of ammunition and the presence of bloodstains affect GSR detection and differentiation using IR photography. 15 types of leaded and 5 types of lead-free 9 mm Luger ammunition were fired onto white cotton fabric and dark-blue denim fabric using the same firearm model, with an additional 14 samples being stained with blood. Resulting GSR patterns varied depending on the ammunition type and fewer GSR particles were visible on denim fabric, even in IR photography, compared to white cotton fabric, but still achieving reliable results comparable to the standard tape-lift method. In addition to the known ability of IR photography to detect GSR from leaded ammunition on clean surfaces, our findings demonstrate for the first time that GSR from lead-free ammunition, as well as GSR on blood-contaminated surfaces can be reliably visualized. In conclusion, IR photography provides a robust, easy-to-use and non-destructive tool for GSR detection, with the distinct benefit of allowing immediate on-site visualization of GSR patterns prior to any laboratory processing. With the use of the custom-made Python script (openly accessible on Github), a quantitative evaluation of GSR comparable to the tape-lift method is a further enhancement in this aspect.

Stiffness and plasticity of human tissues are routinely assessed during forensic autopsy and have recently been identified as a promising metric for estimating time since death in animal models. In this study, the biomechanical state of the human liver is investigated concerning pathology, age at death, sex, liver weight, autolysis, and blood congestion. Additionally, its use for biomechanical time since death estimation is evaluated. The storage, loss, and complex shear moduli of 54 human liver parenchyma samples collected during routine forensic autopsies, were determined using a rheometer. All samples were microscopically analyzed for signs of pathology, autolysis, and blood congestion. High-grade fatty liver samples (n = 6) exhibited significantly higher storage moduli, and complex shear moduli compared to healthy (n = 27), low-grade fatty liver (n = 14), and cirrhotic (n = 7) samples (p ≤ 0.02). High-grade fatty liver samples also had significantly higher loss moduli compared to healthy and cirrhotic samples (p ≤ 0.04). The rheological properties of the human liver were unrelated to age at death (p ≥ 0.26), liver weight (p ≥ 0.13), and sex (p ≥ 0.32). Autolysis significantly increased the loss moduli of healthy liver samples (p = 0.01). Blood congestion significantly lowered the loss moduli of healthy (p = 0.03) and fatty (p < 0.01) samples, as well as storage moduli (p = 0.01), and complex shear moduli (p = 0.01) of fatty samples. A significant positive correlation between the post-mortem interval and the loss modulus was observed for healthy samples, if only samples without signs of blood congestion were included (p = 0.02; n = 9). When stored at 4 °C for an average of eight days post-mortem, liver biomechanics was significantly altered by fatty infiltration, autolysis, blood congestion, and the post-mortem interval, while liver weight, age at death, and sex had no relevant impact.

Nowadays, according to the Istanbul Protocol, diagnostic tests are not an essential part of the clinical assessment of a person alleging torture or ill-treatment. In many cases, a medical history and physical examination are sufficient. However, literature evidence suggests a helpful role of diagnostic imaging in the allegation of evidence of torture, especially in the case of musculoskeletal injuries. The purpose of this narrative review is to highlight the role of imaging tests in suspected torture victims, emphasizing the role of these methods in establishing legal evidence of mistreatment. No specific imaging features are described in the literature, however, musculoskeletal imaging allows the detection of previous fractures, bone deformities, and tendon and ligament injuries. These are mainly due to blunt force injuries. MRI is the most helpful imaging tests to allegate evidence of Falaka. Imaging tests, particularly conventional X-rays and CT, are helpful in forensic investigations of when there is suspicion of retained foreign bodies, such as bullets or shrapnel, especially in cases where clinical examination is inconclusive. CT and MRI can show late sequelae of head trauma such as subdural hematomas, hygromas, old intracerebral bleeding, and hydrocephalus. The current literature highlights the importance of subjecting patients to imaging and specialists examinations to document evidence of torture and support the assessment of the degree of consistency with the reported history. These are second-level investigations that must be targeted to specific diagnostic questions and preceded by a thorough examination conducted by experts in the field using standardized methodologies, in line with the recommendations of the Istanbul Protocol. Imaging studies can bridge the gap between clinical examination and the patient's history.