International Journal of Legal Medicine最新文献

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.

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.

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.

Olze et al. (2010) proposed the use of pulp involution, classified through stages, for dental age estimation by analyzing the lower third molar. However, the absence of this tooth may render the method inapplicable. The aim of this research was to validate the stages of root pulp visibility in the lower second molar for dental age estimation in the Brazilian population. A total of 1,190 orthopantomographs obtained from participants aged between 14.00 and 30.99 years were evaluated. The data were organized and analyzed using Microsoft Excel© (Microsoft Corp., Redmond, WA, USA) and R Studio (R Foundation, Vienna, Austria) software. The prediction of the age of majority achieved an accuracy of 72%. The probability of a person classified in stage 3 being over 18 years old was 100%; for stage 2, it was 95.26%; for stage 1, 82.88%; and for stage 0, 55.9%. Stage 3 was the only one to present a minimum age above 18 years, while stages 0, 1, and 2 had similar minimum and maximum ages. It is suggested that the stages of pulp involution be used for the assessment of age thresholds rather than for age estimation or the determination of a specific age range. It can be concluded that the stages of root pulp visibility in the lower second molar have the potential to be used for predicting the age of majority in Brazil, especially when used in association with other methods. Further studies are necessary in other countries to assess inter-population differences and the method's applicability across different regions.

Age inference is a key focus of forensic work, and traditional dental age inference methods require individuals to have a complete dental arch. However, congenital or acquired tooth loss may lead to random tooth loss in individuals, resulting in bias in age prediction. To address this issue, we validated and modified Bedek's tooth age inference method (a method for inferring the age of a population with missing teeth) for the first time in the Chinese population of children with complete dentition, congenital tooth loss, and acquired tooth loss, and constructed two new machine learning based tooth age inference methods (unilateral mandible and bilateral mandible tooth age estimation models) in this population. The unilateral mandible model was constructed using the remaining five teeth of the left mandible, excluding the lateral incisor and the second premolar of congenital tooth loss, and the first premolars and first molars of the acquired tooth loss, to estimate chronological age (the two most common types of missing teeth in the Chinese population, respectively). However, the actual types of missing teeth in the population are varied, and the information on the location of missing teeth is often replaced by the developmental morphology of the contralateral teeth. In order to augment the predictive information available to model, we further constructed a bilateral mandible model containing 14 individual mandibular teeth by filling in missing values using datawig. In the male agenesis validation group, the MAE values of the best bilateral, unilateral mandible model, and modified Bedek model were 0.641, 0.715, and 0.920, respectively. In females, the MAE values were 0.763, 0.785, and 0.990, respectively. In the male acquired tooth loss validation group, the MAE values of the three models were 0.793, 0.728, and 1.376, respectively. In females, the MAE values were 0.744, 0.779, and 1.094, respectively. Collectively, these novel odontological age-estimation frameworks provide robust, flexible solutions for forensic casework involving partial dentitions. By accommodating variable patterns of congenital and acquired tooth loss without sacrificing predictive precision, they constitute a critical advancement in the forensic identification of unknown or disputed-age individuals.

In forensic practice, accurately estimating post-mortem interval (PMI) is a crucially significant task, as it can provide key clues for cases in forensic medicine. However, it has also been a major challenge since ancient times. Currently, the traditional methods used in forensic medicine to infer PMI mainly include early post-mortem phenomena, corneal opacity, degree of gastric content digestion, and entomological analysis, but are significantly influenced by environmental factors and individual differences, presenting certain defects in terms of precision and applicability. With the advancement of modern molecular biology techniques, the application of gene expression analysis in the area of forensic medicine has gradually become a research hotspot. Moreover, the integration of machine learning algorithms and artificial intelligence (AI) can analyze multi-source data to construct prediction models, thereby improving the correctness of PMI inference and expanding its application scenarios. In this review, we elaborate on the research advancements, mainly in molecular biology or forensic molecular genetics of PMI estimation in forensic medicine. By systematically reviewing the latest research findings of molecular biology in PMI estimation and exploring its future directions, this review also endeavors to offer valuable references for forensic practitioners to improve the reliability of PMI inference in practical forensic potential applications in the future.