International Journal of Legal Medicine最新文献

As the largest human organ, the skin frequently interacts with the environment and retains abundant microbial information, making it a crucial source of forensic biological evidence. However, the temporal dynamics of microbial communities between in situ and in vitro samples, as well as the traceability of in vitro samples back to their donors based on corresponding in situ samples, remain unverified through longitudinal sampling and dynamic tracking. A total of 15 young adult volunteers participated in the study, during which skin microbiome samples were collected from their palms and cheeks. A short-term exposure experiment was designed, with a duration of between 0 and 72 hours. Fresh samples were collected at corresponding timepoints, in a synchronised manner. In this study, we utilised a combination of 16S rRNA gene (V3-V4 regions) sequencing and machine learning algorithms to analyse the environmental exposure effects on microbial community structure and their forensic applicability. The results indicated that the relative abundance of dominant genera remained largely stable, regardless of exposure status, with no significant temporal variations observed in the short term. Although individual lifestyles exerted an influence on microbiome composition, they did not affect significant alterations to the overall community architecture. The random forest model attained an accuracy of 91.33% in skin site identification, while the individual differentiation accuracy attained 97.33% when integrating palm and cheek data. These results indicate that the skin microbiome exhibits considerable structural stability under both in situ and in vitro conditions during short-term exposure and maintains high host specificity and site-specific characteristics.

Objectives: Individual dental age estimation systems provide essential information in law and forensic sciences for the living and deceased. Considering the multi-ethnic population of Australia, it is important to compare the performance of the internationally recognized London Atlas against the Australian-developed Blenkin Taylor age estimation system.

Methods: 218 anonymized digital panoramic radiographs of children aged 5-18 years old were reviewed and 200 met inclusion criteria. The qualified radiographs were subjected to both the London Atlas and Blenkin Taylor age estimation systems, and this was compared to the children's real ages.

Results: The Blenkin Taylor method produced a statistically significant mean underestimation of 0.34 ± 1.44 years, while the London Atlas also produced a statistically significant mean underestimation of 0.96 ± 1.64 years.

Conclusion: Both age estimation systems produced a significantly smaller difference between the estimated and chronological age for females compared to males. Both the London Atlas and Blenkin Taylor are appropriate to apply in an Australian paediatric population for the purposes of forensic age estimation.

This study developed and evaluated data mining models for age estimation and legal age thresholds classification based on elbow MRI in a contemporary Chinese population. A total of 867 patients (614 males and 253 females) aged 30 years or younger were retrospectively included, and T1-weighted coronal elbow MRI images were assessed by experts using five age-related indicators. Multiple data mining models were constructed, with mean absolute error (MAE) as the primary performance metric. Both intra- and inter-observer agreements demonstrated good reliability. In external validation, the optimal model achieved the lowest MAE of 2.9845 years in males and 2.9767 years in females, compared to 2.0471 years and 3.0477 years, respectively, in internal validation. For classification at the 12-, 14-, 16-, and 18-year threshold, the area under the receiver operating characteristic curve (AUC) exceeded 0.90 across all models. Notably, these models also attained the highest specificity (defined as the proportion of individuals truly below the threshold correctly identified) reaching 1.000, 1.000, 0.970, and 0.800 in males, and 1.000, 1.000, 0.857, and 0.750 in females at the respective thresholds. In conclusion, the proposed models show promise in estimating age and classifying legal thresholds, with performance that is generally comparable to that of other MRI-based approaches in certain contexts. These preliminary findings suggest that elbow MRI may serve as a useful tool for age assessment in the Chinese population, though further validation is warranted to confirm its generalizability.

In medico-legal literature, the notion of the "dignity of the corpse" is frequently used as a narrative device, almost romantic in nature, aimed at highlighting the values attributed to it and thereby justifying its defense. The most common explanations tend to focus on its strictly practical effects (in relation to the living), either by pointing to a certain inviolability or by emphasizing some consequences at a symbolic level. Intentionally or not, some of these theories undertake the bold task of explaining the consequences of a phenomenon (the death/dead binomial) while disregarding the study of the material object that sustains this phenomenon, as well as the phenomenon itself. This paper proposes a reflection on the parallels between human dignity (better understood) and the so-called dignity of the dead (practically unknown), advancing an argumentative model (ontological/anthropological) that defends the existence of a 'special dignity of the corpse'. This sui generis dignity demands a sui generis treatment, whose practical applications-both in forensic science and other biological disciplines-can only be determined subsequently, after undergoing moral scrutiny.

Molecular analyses were conducted on skeletal remains discovered in a late medieval burial site beneath the former Convent of San Francesco in Mirandola, Modena, Italy. Part of the burial ground was exposed, revealing infant and adult graves dating to the construction period of the complex (14th-15th centuries AD). Thirty graves were identified which had been buried directly in the ground. They were arranged in several strictly overlapping layers and oriented along an east-west axis in accordance with Christian tradition. The historical context is poorly documented; no archival records are available regarding the causes of death or the reasons for burial at this site. Genetic analyses were conducted to complement the ongoing archaeological and anthropological studies of the site in an attempt to reveal relationships, confirm the number of individuals, explain the burial arrangements, and reconstruct their external appearance and ancestry. Ancient DNA (aDNA) was analysed using the molecular workflow routinely adopted for forensic samples. Teeth and bones were collected. DNA was isolated using a powder-free decalcification and extraction protocol. Autosomal and Y-STR markers were genotyped and Y-haplogroups inferred. The HIrisPlex system was then used to predict eye and hair colour. The results for seventeen individuals are presented herein, alongside an evaluation of the performance of this workflow when applied to severely degraded human remains. The usefulness of the powder-free decalcification protocol was also evaluated, demonstrating its applicability to both ancient and forensic samples of buried skeletal remains recovered under comparable conditions.

Determining the time since death (TSD) is crucial in forensic investigations, yet it remains a complex process influenced by numerous postmortem factors. This study explores RNA degradation as a promising marker for precise TSD estimation, leveraging real-time quantitative polymerase chain reaction to quantify degradation rates. We analysed degradation patterns of messenger RNA (mRNA), ribosomal RNA (rRNA), and microRNA (miRNA) across liver, lung, and heart tissues, focusing on housekeeping genes (GAPDH, ACTB, RPS10, RPS29) and rRNA (5 S, 18 S, 28 S), alongside tissue-specific miRNAs (miR-122, miR-195, miR-200c, miR-1, U6). RNA yield, and purity varied significantly among tissues, with the liver showing higher RNA yields but lower purity compared to the heart and lung. RPS29 and RPS18 emerged as stable reference markers, unlike GAPDH and ACTB, which showed postmortem instability. rRNA demonstrated greater resilience to degradation compared to mRNA, with distinct patterns peaking at 60-84 h postmortem. miRNAs, particularly miR-122, and miR-1, showed potential as TSD biomarkers due to their relative stability. A mathematical model for TSD estimation was developed using 14,400 Ct values from 600 tissues analyzed in R-studio. The model demonstrated high to moderate predictive accuracy across three tissues under controlled environmental conditions. The model achieved the highest accuracy in heart (R² = 0.75), followed by liver (R² = 0.739), with the lowest predictive power observed in lung (R² = 0.57). These findings underscore the effectiveness of RNA degradation profiles, particularly rRNA and microRNAs, in TSD estimation and highlight the importance of integrating multiple tissues and tissue-specific markers for enhanced forensic reliability.

In recent years, several countries have undergone changes in their legal framework, now explicitly allowing the analysis of genetic markers for the purpose of forensic DNA phenotyping (FDP). Consequently, laboratory workflows for the analysis of appearance informative single nucleotide polymorphisms (SNPs) have been established in several laboratories. Currently, the HIrisPlex-S marker panel and webtool are the most widely used set of appearance informative SNP markers and statistical model used for phenotype predictions. However, many different laboratory protocols are employed for SNP genotyping, mostly using either massive parallel sequencing or single base extension technology. For the GEDNAP and TrACE proficiency tests, FDP modules were introduced in 2021 and 2023. These represented the first instances in which identical samples were analyzed by a fairly large number of laboratories, each of them employing their own laboratory-validated protocol. While mostly consistent phenotyping results were obtained, discrepant genotyping results were observed for some of the analyzed HIrisPlex-S-SNPs in BNC2, OCA2, and TYR. By performing a systematic in-silico analysis of commonly used primer sequences and sequencing the flanking regions of target SNPs in the affected samples from the collaborative exercises, we were able to identify primer binding site mutations, amplification of off-target products and overlap of SBE primers as risk factors for (analysis method-dependent) genotyping discrepancies. While the impact on phenotyping results was minor to negligible in all cases reported here, the issues uncovered by this in-depth analysis may provide a basis for improvements towards more consistent results in the future.

Each year, 320 000 people die from occupational injuries. The construction sector is one of the most hazardous sectors, showing a high incidence of workplace fatalities, of which many are caused by traumatic head injuries. In this study, the efficiency of construction helmets has been investigated through an in-depth accident reconstruction of a real-world workplace head trauma, aiming to investigate causation, prevention and liabilities in an ongoing police investigation. The accident was reconstructed with a state-of-the-art subject-specific head model, used to predict the skull fracture and the brain's response to impact. The results of this study show how the skull fracture pattern was predicted with striking resemblance to the real-world fracture and how the locations of high brain strains were predicted in accordance with the victim's brain lesions. The impact scenarios were compared with the hypothetical scenario in which a construction helmet was worn during the impact. The comparison provides evidence to support that a helmet would have prevented the skull fracture, and possibly also life-threatening brain injury. This case study demonstrates how FE reconstructions can help prove causality and liability in fatal head traumas. More importantly, the findings highlight the role of safety helmets in preventing lethal head injuries and their importance in combating the globally high incidence of fatal work-related accidents.

Postmortem interval (PMI) estimation is a pivotal challenge in forensic science, and skeletal muscle protein degradation has emerged as a promising biochemical tool. In this review, we conducted a comprehensive literature search of PubMed for studies published between 2014 and 2024 using keywords related to PMI estimation and protein/proteomics. Of the 287 results retrieved, 81 were available as free full-text articles, and 17 met the inclusion criteria focusing on skeletal muscle protein. The most used techniques were Western blotting, followed by mass spectrometry and immunohistochemistry. Frequently studied proteins included eEF1A2, desmin, GAPDH, α-actinin, vinculin, α-tubulin, and tropomyosin. Although protein degradation in muscle tissue shows significant potential for PMI estimation, relying on a single protein or a small group of proteins is insufficient due to variability introduced by environmental, individual, and species-specific factors. The study highlights the need for long-term, semi-controlled studies using human tissue, as well as further investigation of new candidate biomarkers and the stability of established markers across diverse PMI ranges and conditions. Comparative studies between animal and human data are vital for understanding species differences and ensuring reliable extrapolation. Moving forward, interdisciplinary and methodologically standardized approaches will be critical for integrating protein-based findings into routine forensic practice and achieving a robust, multifactorial method for PMI estimation.