Forensic Science, Medicine and Pathology最新文献

A 74-year-old man underwent both a mitral valve replacement and ascending aorta replacement because of the presence of a critical aneurysm. Postoperatory CT angiography revealed both a periprosthetic hematoma of about 40 mm located at the distal prosthetic graft and a modest effusion at the base of the pericardium. 12 days after the surgery the patient suddenly died. Autopsy showed a cardiac tamponade due to ascending aorta rupture secondary to penetrating atherosclerotic ulcer (PAU). This paper highlights the key gross and microscopic findings of this rare lesion, emphasizing its forensic pathology relevance.

The age of bloodstains at a crime scene provides key information for criminal investigation and interpretation, with important implications in forensic medicine. In this study, silica gel was used as a carrier for bloodstains with different ages to simulate a porous wall surface at an indoor crime scene. A method was developed for bloodstain dating based on attenuated total reflection infrared spectroscopy (ATR-FTIR) and neural networks. Venous blood samples were collected from nine healthy volunteers, and ATR spectra were recorded at five points for each sample during a period of 7 days. The neural networks TRAINSCG, TRAINLM, and TRANGDM were constructed. The training dataset was the ATR spectra (4,000-600 cm^- 1) of samples collected from seven participants (YP1-YP7) and recorded at five points over 7 days (a total of 245 spectra). The prediction dataset was 70 spectra from two participants (YP8 and YP9). The prediction accuracy of the neural networks was compared with different numbers of hidden layers and neurons. The key absorption peaks at 1800-1300 cm^- 1 were used for neural network training and bloodstain dating. The neural network trained using the Levenberg-Marquardt algorithm based on ATR spectra (1800-1300 cm^- 1) was used for predicting the age of bloodstains on silica gel. The coefficient of determination (R²) for predicted and actual bloodstain ages was up to 0.9215 after removing outliers. ATR used in combination with neural networks provides a non-destructive and rapid method for bloodstain dating. Neural networks constructed using different algorithms showed varying performance in bloodstain dating with ATR. Prediction accuracy was improved with the Levenberg-Marquardt algorithm and key peaks.

Forensic odontology (FO) plays a crucial role in legal and humanitarian investigations, providing expert testimony and contributing to disaster victim identification (DVI). However, comprehensive global data on the demographics, distribution, and professional activities of forensic odontologists (FOs) remain limited. This pilot study aimed to explore the global landscape of FO by examining the demographic profiles, geographic distribution, professional engagement, and career trajectories of practitioners in the field. A descriptive cross-sectional design was employed, utilizing a 26-item self-administered online questionnaire developed via Microsoft Forms. The survey, comprising both open-ended and multiple-choice questions, was disseminated globally to FOs and FO students through WhatsApp®, LinkedIn®, ResearchGate®, and professional associations' email lists. A total of 206 qualified FOs and students participated in the study. The results indicated that 40.3% of respondents practice in regions where FO is formally recognized as a specialty, with notable regional disparities. Although a significant proportion reported involvement in forensic casework, 27.7% expressed dissatisfaction with the level of support and professional recognition. One of the most pressing barriers identified was the absence of FO in undergraduate dental curricula and the limited availability of specialized training programs. The survey also underscored the diverse professional roles of FOs, including participation in court proceedings, mass disaster response, and forensic research. Key challenges reported by respondents included limited recognition of the field (21.8%), restricted career opportunities (18.4%), and inadequate access to training resources (13.1%). Additionally, specific technical challenges-such as bite mark analysis and dental age estimation-were highlighted as areas requiring further attention. This study offers valuable insights into the geographic distribution and professional scope of FOs, providing a foundation for future research with expanded outreach to ensure a more globally representative sample.

Cadaveric blood is ubiquitous, and observed in various forms-liquid, coagulated, and clot-like-during autopsies. Understanding its state in postmortem vessels is essential for both scientific research and forensic investigations. Pulmonary thromboembolism (PT) is a leading cause of sudden death, often requiring medicolegal evaluation. While thrombus formation is primarily explained by Virchow's triad, the distinction between antemortem, agonal, and postmortem clot (PMC) pathogenesis remains debated. This study aims to systematically review the literature to clarify the morphological and pathological differences among these entities in forensic practice. A systematic review of PubMed, Science Direct, Scopus, and Web of Science was conducted using predefined key terms: "clot," "thrombus," "chicken-fat," "agonal," "postmortem," and "autopsy." Articles were screened for relevance, and 11 studies meeting the inclusion criteria were analyzed. The review highlights a significant gap in comparative studies addressing antemortem versus postmortem clots. The literature lacks a consensus regarding their definitions, macroscopic and microscopic characteristics, pathogenesis, and relevance to determining the cause and timing of death. Existing studies present conflicting interpretations, limiting the reliability of forensic differentiation. The current understanding of antemortem, agonal, and postmortem clots remains incomplete. Our findings underscore the need for further research to establish standardized criteria for distinguishing clot types, which is crucial for forensic pathology and medicolegal evaluations.

Conducted electrical weapons (CEWs) are widely employed by law enforcement agencies globally to manage and restrain potentially violent individuals. As newer generations of these weapons are introduced, it is crucial to assess their effectiveness and safety profiles. The TASER 10 (T10) represents a significant advancement, utilizing an independently targeted probe system with floating polarities, enabling any two probes to establish a connection. This design enhances its versatility and operational effectiveness compared to earlier models. In scenarios requiring use over greater distances- such as deployment via drones-prolonged electrical exposure may be necessary to bridge the gap to the subject and secure control of the situation. The extended exposure duration associated with these probes may result in altered wound mechanisms and morphological features. This study examines the morphological wound characteristics of 20-30 s of electrical exposure delivered through hand-placed dart electrodes of the T10 CEW. To our knowledge, this represents the first human study to investigate potential electrical injuries resulting from extended-duration exposure with the T10 CEW.

Saliva is a frequently encountered body fluid at crime scenes, however currently there are no definite means to rapidly identify a body fluid as being saliva. In this study, a novel detection method for saliva using a modified Loop-mediated Isothermal Amplification (LAMP) integrated with CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeat-CRISPR associated protein) and LFA (Lateral Flow Assay) was developed to detect the expression of a saliva-specific gene: follicular dendric cell secreted protein (FDCSP). To determine the specificity of the assay, RNA from saliva plus other commonly encountered body fluids was tested (peripheral blood, semen, vaginal fluid, and menstrual blood): positive results were only observed from RNA extracted from known saliva samples and RNA from all the other body fluids exhibited a negative result. To assess the reproducibility, triplicates were used from one saliva sample, and the assay was performed on three different days: positive results were observed from all triplicates. The limit of detection was 2^-6 (0.3906 ng RNA) or 2^-7 (0.1953 ng RNA). This preliminary study for the identification of saliva requires no complex equipment and is easy to perform, offering an alternative means for body fluid identification.

There are only few reports on the neuropathologic findings of fire victims. We investigated brain tissues of a 44-year-old and a 77-year-old man for neuropathologic examination with dehydration, embedding in celloidin, sectioning at 400 μm, and staining with gallocyanin. Microscopically, neurons were less well stained than those from an 87-year-old woman who died of cancer and whose brain had been fixed in formalin for three months. Glial cells were optimally stained. We observed local, laminar and disease-related qualitative and quantitative differences in the amygdaloid complex, temporal allo- and isocortex together with hyperchromatic staining of the medullary layer in the temporal lobe of both fire cases. The vasculature was well preserved and free of blood cells or clotted blood. The heat in fire deaths apparently acts as a kind of fixation, similar to the intention of formalin use, without the confounding effects of agonal and postmortem factors. Heat is most likely a major factor in microwave fixation. Thick gallocyanin-stained sections allow intuitive visual diagnosis of local and laminar neuronal degeneration or gliosis and have the potential to enhance and refine neuropathology-related diagnoses.

Purpose: Superfecundation, the fertilization of two oocytes by different spermatozoa within the same ovulatory cycle, can result in monopaternal or heteropaternal dizygotic twins. While monopaternal superfecundation is more common, heteropaternal superfecundation is rare and typically seen in disputed paternity cases. This study presents a case of heteropaternal superfecundation confirmed through forensic DNA analysis and reviews its occurrence in existing literature.

Methods: A forensic investigation was conducted in a court-ordered paternity case involving dizygotic twins, their mother, and an alleged father. Buccal swab samples were collected and analyzed using multiplex amplification of 19 STR markers and the amelogenin locus. A second DNA test confirmed the results. Additionally, a dataset of 2,679 paternity tests over 10 years was examined to estimate paternity exclusion rates in twin cases.

Results: Genetic analysis confirmed the alleged father's paternity of twin 1 but not twin 2, with 14 out of 19 STR loci showing absent alleles in twin 2. The 10-year dataset showed 553 paternity exclusions (20.64% of cases), with 31 involving twins, of which one case (3.23%) was identified as heteropaternal superfecundation. No significant difference was found between paternity exclusion rates in twin and non-twin cases.

Conclusions: This case underscores the value of forensic genetic testing in detecting heteropaternal superfecundation, a rare occurrence with legal and social implications. Advances in DNA analysis may lead to more frequent identification of such cases.