Assessing violent mechanical asphyxia in forensic pathology: State-of-the-art and unanswered questions.

Mechanical asphyxiation has been a common method used to commit homicide, including femicide, throughout history. A recent report by the United Nations has shed light on the issue of misidentification and concealment of gender-related killings, which makes it difficult to effectively fight against it. Forensic pathologists are frequently asked to examine cases involving suspected asphyxia to determine whether other persons have been involved. Therefore, medicolegal experts must look for signs of occlusion of the oral/nasal orifices, compression of the neck, or specific signs such as the "facie sympathique". There are situations where the physical signs are not distinctive enough to diagnose asphyxia, especially in cases where the individual has limited ability to resist external compression. In such cases, judicial autopsies should include an anatomical dissection of the neck structures through a layer-by-layer progression. It is important to search for the Amussat's sign, e.g., as part of a Forensic Clinical Anatomy approach. Additionally, individual anatomical variations, age or artefactual modifications, must be considered for the correct interpretation of findings. Microscopic examinations could aid in the diagnosis by providing additional findings, and several attempts have been made to identify unique markers of asphyxia through various laboratory techniques such as biochemistry, radiology and miRNA studies. However, no single finding or method has been identified as definitive. In the future, biomedical-legal sciences will have to rely on scientific research and the retrospective case series to provide a scientific framework on which to base their hypothesis, giving weight to evidence in the trial.

Microscopic analysis of cut mark characteristics from chopping/hacking tools.

Evaluating sharp force trauma (SFT) injuries to bone inflicted by a larger class of chopping/hacking tools (i.e., swords, axes, hatchets, machetes, and cleavers) is a growing area within the field of forensics. Previous studies have demonstrated promise regarding tool differentiation through the utilization of microscopic cut mark characteristics. However, this is an area that warrants additional investigation as there has yet to be a comprehensive study that incorporates the majority of these microscopic chopping/hacking cut mark characteristics into one analysis. The purpose of the current research was to analyze a large sample of microscopic cut mark characteristics derived from the current chopping/hacking literature to determine if differentiation of tool type could be made based on the microscopic cut mark characteristics. An additional goal of the current research is to develop standardization guidelines for the assessment of cut marks, focusing on a comprehensive suite of microscopic cut mark characteristics commonly observed in the existing literature. The skeletal sample for the current research was derived from a previous macroscopic cut mark characteristic experiment where trauma was inflicted to 20 partially fleshed domestic pig (Sus scrofa domesticus) limbs utilizing four chopping/hacking tools (i.e., axe, hatchet, machete, and cleaver) as well as a large carving knife for comparison. Cut marks were evaluated for 15 microscopic cut mark characteristics to assess statistical significance. Utilizing a chi-square analysis, nine of the 15 microscopic cut mark characteristics demonstrated statistically significant differences in relation to the tool utilized, indicating moderate to relatively strong effect sizes. For example, it should be possible to use a combination of microscopic cut mark characteristics to potentially indicate which chopping/hacking tool inflicted trauma when analyzing bones. In particular, examining the characteristics such as regularity of the cut mark edges along with the occurrence of uprising, fossae/depressions, and microscopic fractures can suggest or exclude tool class within forensic contexts.

Identification of bullet holes in mummified corpse.

Background: The evaluation of the cause of death in a forensic context is often challenging especially when the corpse is in a severely altered state (decomposed, skeletonized, charred, dismembered, etc.), thus making it difficult to obtain an overview of the features and/or lesions suggestive of the dynamics leading to death. Case Report: In this case, the corpse was partly in a state of saponification and partly in a state of mummification with signs of skeletonization. The head, trunk, arms and upper legs were mummified and almost completely dehydrated. Conclusion: The use of special techniques such as the rehydration of bodies is an ancient practice. Parts of skin in different states of decomposition with the use of rehydration solution represents a useful procedure for the study of some damaging modalities, being able to identify damaged areas characterized by compression/dehydration effects, hidden by the advanced transformative state of the corpse, highlighting very damaged, in which skin normality can no longer be restored.

Asphyxia with a blunt instrument: which forensic evidence to use in complex cases of murder.

Background: The blunt injuries may be heterogeneous. Due to the diversity, it is often difficult to establish the type of weapon used. Particular attention must be paid to the circumstantial data and previous diseases because the injuries often could not correspond to the presumed instruments used. Case Report: A man was found dead in his bedroom wearing pajamas. On the bed there was a blanket with visible traces of blood, which had dried. There were around 10 dogs in the house, poor hygienic and sanitary conditions, widespread excrements and unbreathable air. Testimonies from general practitioner, neighbors and the partner were collected. An autopsy, histological and toxicological examination was performed. On external examination the face showed blood smearing down the nose, subconjunctival hemorrhages, and labial cyanosis. Mo-reover, a hypochromic skin area was present on the right lateral region of the neck. The inguinal region showed large de-epithelized areas with multiple purplish red ecchymoses which were histologically analyzed. These areas showed hemorrhagic infiltration in the superficial and deep dermis up to the adipose tissue due to traumatic action. Conclusion: The reconstruction of the case allowed us to state a strangulation probably attributable to a belt. The discovery of intradermal hemorrhagic infiltrations, supported by histopathological investigations, confirmed the diagnosis of blunt force injuries, excluding other type of non-violent causes of lesions. Therefore, we recommended the use of experimental methods and procedures to evaluate the harmful suitability on biological matrices.

The role of necroscopy and autopsy investigations in the diagno-sis and risk management of infections related to public health care: forensic and medico legal implications.

Background: Healthcare-associated infections (HAIs) represent the most frequent adverse event in healthcare systems around the world. From a forensic point of view, HAIs show various legal implications. Therefore, it is essential in cases of death or injury from a suspected nosocomial infection that the infection itself, the source and the method of contamination are correctly diagnosed in order to evaluate any profiles of professional liability. Methods: This study combined a minireview of the scientific literature using the Pubmed search engine, the website of the Higher Institute of Health and the member states information sessions on infection prevention and control (IPC). Discussion: Despite the significant impact that HAIs have on healthcare systems, their severity is often not fully understood by healthcare professionals, leading to insufficient responses. In the autopsy setting, the diagnosis of these infections is not always simple due to the risk of post-mortem contamination determined by the endogenous bacterial flora. In the forensic field, the medical examiner during the autopsy can use various diagnostic techniques and investigative tools to identify the infection. Some usefulpp approaches include: 1) Macroscopic examination of the organs; 2) Histopathological investiga-tions; 3) Microbiological analyzes with the performance of swabs; 4) Immunofluorescence tests for the detection of antigens or antibodies on biological liquids; 5) Molecular tests. The choice of methods will depend on the nature of the suspected infection and the availability of diagnostic resources.

[Forensic assessment of neck organs alterations in hanging depending on the noose position]. / Sudebno-meditsinskaya otsenka izmenenii v organokomplekse shei pri poveshenii v zavisimosti ot polozheniya petli.

OBJECTIVE: To reveal statistical patterns in the localization of alterations in organs and tissues of the neck in hanging depending on the noose location. MATERIAL AND METHODS: In this study 222 forensic examination reports of corpses of those who died from hanging, conducted in the Bureau of Forensic Medical Expertise of Moscow Oblast for 2019, were investigated. Standard methods of mathematical statistics, including Mann-Whitney U Test and the Fisher's Exact Test, were used for calculations. Sex and age characteristics of hanging cases were given. RESULTS: Retrospective statistical analysis has shown that the pattern of injuries revealed in organs and tissues of the neck both depends (in cases of Amussat's sign) and does not depend (in cases of hemorrhages in the legs of sternocleidomastoid muscle, fractures of the hyoid bone and thyroid cartilage, Martin's sign) on the noose position. CONCLUSION: The obtained results can be used to develop measures aimed at improving the quality of forensic examination of hanging cases.

[Forensic characteristic of damages caused by offensive grenades detonation]. / Sudebno-meditsinskaya kharakteristika povrezhdenii, prichinennykh pri vzryve nastupatel'nykh granat.

OBJECTIVE: To determine the specific morphological features of damages on the cloth and biological simulator of the human body in the detonation of RGD-5 and RGN fragmentation hand offensive grenades. MATERIAL AND METHODS: The study was carried out on the 12 targets from a biological simulator of the human body wrapped in cotton cloth by detonation of examined grenades at a distance of 50 cm and 1 m from the target. RESULTS: The character and features of damages of cloth and human body biological simulator, features of soot deposition made it possible to determine specific signs for each of examined offensive grenades types. CONCLUSIONS: The complex of obtained data allows to determine with high accuracy the detonation distance and the type of explosive device.

The use of dye to detect sites of hemorrhage and leak in postmortem cases.

This study introduces a novel, cost-effective, and rapid method for identifying hemorrhage or leakage sites following postoperative deaths, a critical aspect in the context of medical malpractice litigation. The technique employs diluted ink as an injectable dye, providing an alternative to postmortem contrast imaging. The utility of this method was demonstrated through a series of three cases. In the first case, the technique successfully detected leaks within vascular structures. The second case revealed a leakage in the cystic duct, while in the third case, the method was instrumental in identifying a leak in a hollow organ situated below the gastro-esophageal junction. Given its demonstrated efficacy, this technique has been incorporated into routine practice by the forensic pathologist in the medicolegal directorate in Baghdad, Iraq.

Selective postmortem arterial angiography of head and neck using digital x-ray or computed tomography: A practical and rapid method to identify vascular injuries.

Identification of vascular injuries is crucial for complete postmortem evaluation and understanding of trauma deaths by the Medical Examiner. Some vascular injuries are difficult to evaluate due to challenging anatomic locations, especially in the head and neck. Documenting injuries of the facial and vertebral arteries is challenging and necessitates time-consuming dissections that can create artifacts and disfigurement. In busy medical examiner offices with a significant number of traumatic injuries, finding a creative solution to employ reliable postmortem angiography is desirable. At the Office of the Chief Medical Examiner for the State of Maryland (OCME), we created and effectively implemented a selective angiography procedure using traditional indwelling Foley catheters and water-soluble barium swallow contrast to evaluate arterial injuries using either digital radiography or computed tomography imaging modalities. This technique and imaging interpretation can be performed by a medical examiner or forensic pathology fellow after basic technical training and basic radiology training. This study outlines the technique, methods, and utilization of the procedure and describes the findings of six deaths due to vascular lesions from different injury mechanisms and disease processes and describes the ease of implementation on a broader scale in busy Medical Examiner's offices.

New perspectives of forensic pathology through machine learning approach on autopsy data: a pilot study.

Background: The analysis, interpretation and storage of information is entrusted to the individual expert, who bases his judgments on the knowledge resulting from the experience. The aim of this experimental study is to analyse and introduce a new line of research applicable to forensic pathology, based on the use of artificial intelligence techniques as a possible tool for data collection and analysis. Methods: The sample analysed is represented by judicial autop-sies performed at the University of Catanzaro from 01/01/2020 to 31/12/2021. For each case were performed: study of medical records; autopsy; histological examinations; toxicological analysis of blood samples. Continuous variables were presented as means ± standard deviations, and categorical variables were expressed as percentages. A random forest regression model was conducted, as a machine learning approach, to estimate the importance of individual solid organ weight variables in predicting cause of death. Conclusions: This study aimed to evaluate autopsy data to aid in the description and study of forensic cases, using a machine learning approach. To date, this study appears to be the first to evaluate the weight of organs in predicting a cause of death. Artificial intelligence techniques are an optimal solution in solving forensic dilemmas. The results of this study demonstrate that routine data can be submitted using machine learning techniques in order to identify key elements of procedures that provide more information in relation to the predic-tion of cause of death.

Heart proteomic profiling discovers MYH6 and COX5B as biomarkers for sudden unexplained death.

Sudden unexplained death (SUD) is not uncommon in forensic pathology. Yet, diagnosis of SUD remains challenging due to lack of specific biomarkers. This study aimed to screen differentially expressed proteins (DEPs) and validate their usefulness as diagnostic biomarkers for SUD cases. We designed a three-phase investigation, where in the discovery phase, formalin-fixed paraffin-embedded (FFPE) heart specimens were screened through label-free proteomic analysis of cases dying from SUD, mechanical injury and carbon monoxide (CO) intoxication. A total of 26 proteins were identified to be DEPs for the SUD cases after rigorous criterion. Bioinformatics and Adaboost-recursive feature elimination (RFE) analysis further revealed that three of the 26 proteins (MYH6, COX5B and TNNT2) were potential discriminative biomarkers. In the training phase, MYH6 and COX5B were verified to be true DEPs in cardiac tissues from 29 independent SUD cases as compared with a serial of control cases (n = 42). Receiver operating characteristic (ROC) analysis illustrated that combination of MYH6 and COX5B achieved optimal diagnostic sensitivity (89.7 %) and specificity (84.4 %), with area under the curve (AUC) being 0.91. A diagnostic software based on the logistic regression formula derived from the training phase was then constructed. In the validation phase, the diagnostic software was applied to eight authentic SUD cases, seven (87.5 %) of which were accurately recognized. Our study provides a valid strategy towards practical diagnosis of SUD by integrating cardiac MYH6 and COX5B as dual diagnostic biomarkers.

Could synovial fluid be a useful substrate for the forensic analysis of diatoms?

To date, synovial fluid has not been the subject of targeted analysis as a possible substrate to search for the presence of diatoms in the forensic context of drowning. However, its unique characteristics of production and isolation from the external environment could make it suitable for this purpose, similar to what has already been demonstrated in the literature for vitreous humor. By considering this, synovial fluid was analyzed in a specific case that came to our attention, where the coexisting signs of polytrauma and drowning were documented during autopsy, demonstrating a period of vitality during immersion. After a thin smear of the supernatant was obtained from the centrifugation of the synovial fluid sample, diatoms were successfully detected, consistent with those found in other organs and the water of the canal. The detection of diatoms in the synovial fluid was an objective finding, but its generalizability is limited because this was a pilot application. However, in cases where death by drowning is suspected and the body has multiple areas breached by trauma, the technique of analyzing diatoms in the synovial fluid could have great potential. Therefore, it is appropriate to further explore this technique in order to obtain more forensic evidence in such a setting.

Relationship between N-terminal pro-brain natriuretic peptide concentration and heart-type fatty acid-binding protein in postmortem urine.

The clinical use of N-terminal pro-brain natriuretic peptide (NT-proBNP) and blood concentrations of heart-type fatty acid-binding protein (HFABP) is well-established in diagnosing heart conditions. However, their applicability in forensics is controversial due to postmortem changes. NT-proBNP and HFABP are excreted in the urine due to their small molecular weights and may be found in postmortem urine samples; however, their correlation has not been evaluated. In this study, we compared the concentrations of urinary NT-proBNP and HFABP in 386 forensic autopsy cases. The urinary NT-proBNP levels were significantly higher in acute myocardial infarction (AMI), congestive heart failure (CHF), sepsis, and hyperthermia cases, with the highest levels in CHF cases. Similarly, HFABP concentration was significantly higher in CHF, sepsis, and hyperthermia cases, with the highest level observed in hyperthermia cases. However, the difference in urinary HFABP levels between the AMI and control cases was not significant. Our analysis revealed a correlation between postmortem urine NT-proBNP and HFABP levels, and the NT-proBNP/HFABP ratio was high in patients with CHF and sepsis cases and low in those with hyperthermia. The difference between the ratios was possibly due to the combined release of ventricular myocardial cells in response to ventricular wall stress and myocardial injury for NT-proBNP, as well as myocardial and skeletal muscle injuries for HFABP. This study, for the first time, demonstrates the utility of postmortem measurements of urinary NT-proBNP and HFABP levels, offering valuable insights for improving the accuracy of postmortem diagnosis in forensic medicine.

[Is this iatrogenic pathology or rare disease?] / Yatrogennaya patologiya ili redkaya bolezn'?

The article is devoted to the problem of diagnosis and treatment strategy of Buerger's disease rarely found in the expert and clinical practice, that is inflammatory disease of unknown etiology, affecting mainly small and medium arteries and veins of limbs. Vascular surgeons around the world have been solving this problem for many years, both in terms of timely diagnosis of this disease and its proper pathogenic treatment. The authors of the article described an expert case of Buerger's disease larvated course in 15-years-old girl, which primarily was mistakenly assessed by specialists as iatrogenic pathology of right forearm vessels in injecting aminazin solution that, according to the clinicians' opinion, led to dry gangrene formation of right wrist and its subsequent amputation. The results of the forensic histological study and retrospective analysis of all child's medical documents allowed to correctly diagnose this rare pathology but only on the stage of commission forensic medical examination in the framework of the initiated criminal proceeding against several leading medical organizations in Saint-Petersburg with a pediatric profile. The authors noted the role of routine medical manipulation in manifestation of larvated pathologic process in a teenage girl in addition to full health and well-being. The objective of present article is devoted to understanding this problem.

[Diagnostic criteria of death cause from low temperature in air and water established by traditional expert examination methods]. / Diagnosticheskie kriterii prichiny smerti ot deistviya nizkoi temperatury na vozdukhe i v vode, ustanavlivaemye s pomoshch'yu traditsionnykh metodov ekspertnogo issledovaniya.

Death from general hypothermia is one of the leading causes in the structure of violent death in the Russian Federation. OBJECTIVE: To clarify and supplement the complex of differential diagnostic macro- and microscopic signs of a fatal acute general cold trauma received when person is in the air and water. MATERIAL AND METHODS: The conclusions of forensic medical experts on the bodies of people who died from hypothermia in the air and in water (by 150 observations) were analyzed. Methods of descriptive statistics, calculation of the frequency ratio of signs' occurrence were used. RESULTS: The article provides quantitative assessment of occurrence (detection) rate of diagnostically significant signs established with the help of traditional methods of expert examination. A new classification of diagnostic death signs from hypothermia taking into account their differential diagnostic significance and reflecting the conditions of a person's stay in the air and water in the pre-mortem and post-mortem periods, as well as terminal period mechanisms is proposed. CONCLUSION: The established complexes of signs provide an objective basis for determining death cause in non-obvious conditions when cold exposure is expected to be one of the most damaging factors.

Traumatic axonal injury: Clinic, forensic and biomechanics perspectives.

Identification of Traumatic axonal injury (TAI) is critical in clinical practice, particularly in terms of long-term prognosis, but also for medico-legal issues, to verify whether the death or the after-effects were attributable to trauma. Multidisciplinary approaches are an undeniable asset when it comes to solving these problems. The aim of this work is therefore to list the different techniques needed to identify axonal lesions and to understand the lesion mechanisms involved in their formation. Imaging can be used to assess the consequences of trauma, to identify indirect signs of TAI, to explain the patient's initial symptoms and even to assess the patient's prognosis. Three-dimensional reconstructions of the skull can highlight fractures suggestive of trauma. Microscopic and immunohistochemical techniques are currently considered as the most reliable tools for the early identification of TAI following trauma. Finite element models use mechanical equations to predict biomechanical parameters, such as tissue stresses and strains in the brain, when subjected to external forces, such as violent impacts to the head. These parameters, which are difficult to measure experimentally, are then used to predict the risk of injury. The integration of imaging data with finite element models allows researchers to create realistic and personalized computational models by incorporating actual geometry and properties obtained from imaging techniques. The personalization of these models makes their forensic approach particularly interesting.