Immunohistochemical expression of HMGB1 and related proteins in the skin as a possible tool for determining post-mortem interval: a preclinical study.

Determining the post-mortem interval (PMI) is one of forensic pathology's primary objectives and one of its most challenging tasks. Numerous studies have demonstrated the accuracy of histomorphology and immunohistochemical investigations in determining the time of death. Nevertheless, the skin, a robust and easy-to-remove tissue, has only been partially analyzed so far. By studying 20 adult male mice, we tried to determine whether post-mortem immunohistochemical detection in the skin of HMGB1 proteins and associated components (Beclin1 and RAGE) could be used for this purpose. We discovered that nuclear HMGB1 overexpression indicates that death occurred within the previous 12 h, nuclear HMGB1 negativization with high cytoplasmic HMGB1 intensity indicates that death occurred between 12 and 36 h earlier and cytoplasmic HMGB1 negativization indicates that more than 48 h have passed since death. RAGE and Beclin1 levels in the cytoplasm also decreased with time. The latter proteins' negativization might indicate that more than 24 and 36 h, respectively, have passed from the time of death. These indicators might potentially be helpful in forensic practice for determining the PMI using immunohistochemistry.

Post mortem computed tomography meets radiomics: a case series on fractal analysis of post mortem changes in the brain.

Estimating the post-mortem interval is a fundamental, albeit challenging task in forensic sciences. To this aim, forensic practitioners need to assess post-mortem changes through a plethora of different methods, most of which are inherently qualitative, thus providing broad time intervals rather than precise determinations. This challenging problem is further complicated by the influence of environmental factors, which modify the temporal dynamics of post-mortem changes, sometimes in a rather unpredictable fashion. In this context, the search for quantitative and objective descriptors of post-mortem changes is highly demanded. In this study, we used computed tomography (CT) to assess the post-mortem anatomical modifications occurring in the time interval 0-4 days after death in the brain of four corpses. Our results show that fractal analysis of CT brain slices provides a set of quantitative descriptors able to map post-mortem changes over time throughout the whole brain. Although incapable of producing a direct estimation of the PMI, these descriptors could be used in combination with other more established methods to improve the accuracy and reliability of PMI determination.

Estimation of the time of death by measuring the variation of lateral cerebral ventricle volume and cerebrospinal fluid radiodensity using postmortem computed tomography.

Using postmortem CT (PMCT), changes in the volume of the lateral cerebral ventricles (LCVs) and modifications of the radiodensity of cerebrospinal fluid (CSF) have been examined to identify a possible relationship between these changes and the time of death. Subsequent periodical CT scans termed "sequential scans" for ten corpses at known time of death were obtained, and a 3D segmentation of the entire LCV was carried out to measure its volume and radiodensity over time from ~ 5.5- h up to 273-h postmortem. A linear decrease of the LCV volume for all the cases was observed in the investigated time range, together with an overall logarithmic increase of radiodensity. Although a larger sampling should be performed to improve the result reliability, our finding suggests that the postmortem variation of CSF radiodensity can be a potentially useful tool in determining postmortem interval, a finding that is worthy of further investigation.

Postmortem CT and autopsy findings in nine victims of terrorist attack.

In a foreign country, a religious terrorist group raided a restaurant, using pipe bombs, sharp-edged weapons, and various types of firearms (handguns, submachine guns, and AK-47 assault rifles) loaded with normal and prohibited bullets to kill foreigner customers, some of whom were Italian tourists. Local pathologists performed forensic autopsies on the bodies, but we were asked to perform additional external examinations, postmortem computed tomography (PMCT) scans, and then a second round of complete autopsies on nine victims (5 females and 4 males). Four victims had slash wounds inflicted by sharp-edged weapons, mostly localized in the head and neck. All but two victims had gunshot wounds. Finally, three casualties had injuries caused by the explosion of improvised explosive devices. In all cases, PMCT was a reliable source of information and provided strategic guide during autopsies, helping identify and describe the injuries and thus reconstruct the events. Therefore, in these cases, we suggest integrating the autopsy findings with the postmortem radiological data.

An evaluation of the objectivity and reproducibility of shear wave elastography in estimating the post-mortem interval: a tissue biomechanical perspective.

Cadaveric rigidity-also referred to as rigor mortis-is a valuable source of information for estimating the time of death, which is a fundamental and challenging task in forensic sciences. Despite its relevance, assessing the level of cadaveric rigidity still relies on qualitative and often subjective observations, and the development of a more quantitative approach is highly demanded. In this context, ultrasound shear wave elastography (US SWE) appears to be a particularly well-suited technique for grading cadaveric rigidity, as it allows non-invasive quantification of muscle stiffness in terms of Young's modulus (E), which is a widely used parameter in tissue biomechanics. In this pilot study, we measured, for the first time in the literature, changes in the mechanical response of muscular tissues from 0 to 60 h post-mortem (hpm) using SWE, with the aim of investigating its applicability to forensic practice. For this purpose, 26 corpses were included in the study, and the muscle mechanical response was measured at random times in the 0-60 hpm range. Despite the preliminary nature of this study, our data indicate a promising role of SWE in the quantitative determination of cadaveric rigidity, which is still currently based on qualitative and semiquantitative methods. A more in-depth study is required to confirm SWE applicability in this field in order to overcome some of the inherent limitations of the present work, such as the rather low number of cases and the non-systematic approach of the measurements.

A novel method for post-mortem interval estimation based on tissue nano-mechanics.

Forensic estimation of post-mortem interval relies on different methods, most of which, however, have practical limitations or provide insufficient results, still lacking a gold standard method. In order to better understand the phenomenon of rigor mortis and its applicability to the post-mortem interval estimation, we decided to use atomic force microscopy, a tool often employed to measure mechanical properties of adherent cells. Thus, we surgically removed skeletal muscle samples of three forensic cases from 0 to 120 h post-mortem and quantitatively evaluate two parameters: the Young's modulus (E), which gives information about the sample stiffness, and the hysteresis (H), which estimates the contribution of viscous forces. Despite being a preliminary study, the obtained results show that the temporal behavior of E well correlates with the expected evolution of rigor mortis between 0 and 48 h post-mortem, and then monotonically decreases over time. Unfortunately, it is strongly affected by inter-individual variability. However, we found that H provides measurable data along a time-dependent curve back to the starting point, and these data measured on different subjects collapse onto a single master curve, getting rid of the inter-individual variability. Although a larger sampling should be performed to improve the result reliability, this finding is strongly suggestive that the evaluation of rigor mortis should involve the measure of the nanoscale dissipative behavior of muscular tissues.

Medico-legal perspectives on sudden cardiac death in young athletes.

Sudden cardiac death (SCD) in a young athlete represents a dramatic event, and an increasing number of medico-legal cases have addressed this topic. In addition to representing an ethical and medico-legal responsibility, prevention of SCD is directly correlated with accurate eligibility/disqualification decisions, with an inappropriate pronouncement in either direction potentially leading to legal controversy. This review summarizes the common causes of SCD in young athletes, divided into structural (hypertrophic cardiomyopathy, arrhythmogenic cardiomyopathy, congenital coronary artery anomalies, etc.), electrical (Brugada, congenital LQT, Wolf-Parkinson-White syndrome, etc.), and acquired cardiac abnormalities (myocarditis, etc.). In addition, the roles of hereditary cardiac anomalies in SCD in athletes and the effects of a positive result on them and their families are discussed. The medico-legal relevance of pre-participation screening is analyzed, and recommendations from the American Heart Association and European Society of Cardiology are compared. Finally, the main issues concerning the differentiation between physiologic cardiac adaptation in athletes and pathologic findings and, thereby, definition of the so-called gray zone, which is based on exact knowledge of the mechanism of cardiac remodeling including structural or functional adaptions, will be addressed.

The Differential Diagnosis Between Natural Death and Homicide, an Everlasting Challenge for the Forensic Pathologist: An Exemplar Case Report.

Most of the work performed by the forensic expert is to find proof for different plausible hypotheses that may be used in a trial to serve justice purposes when the "identity" of a case is already unveiled. Yet the previous phase of the investigation is also of great importance, and sometimes (like in the presented case), it represents the core element of the entire investigation. The appropriate determination of the differential diagnosis between a natural death and a death of forensic interest (ie, homicide) is the first and crucial step in the classification of a case. This article analyzes the case of the body of a man found lying on the border of a country road with his wrists tied up with rope and the resulting investigation performed by the medicolegal forensic expert. In the end, as more specific examinations where performed aimed to find the truth, the final conclusions excluded a violent death and confirmed that the cause of the death was an acute myocardial infarction.

Visualization of myocardial infarction by post-mortem single-organ coronary computed tomography: a feasibility study.

INTRODUCTION: Post-mortem imaging is increasingly used in forensic field in cases of natural deaths related to cardiovascular diseases, which represent the most common causes of death in developed countries. While radiological examination is generally considered to be a good complement for conventional autopsy, it was thought to have limited application in cardiovascular pathology. The aim of this study was to investigate the role of post-mortem multidetector coronary artery computed tomography in cases of sudden death in adults. MATERIALS AND METHODS: We have enrolled 11 cases, all of whom were negative for macroscopic extra-cardiac lethal findings after standard autopsy procedure. Later, from the same individuals, isolated single-organ post-mortem computed tomography coronarography (PMCTA), using an iodinated non-ionic contrast medium, was achieved. After computed tomography examination, all the isolated hearths were carried to the forensic pathologist, and a conventional histology assessment was performed on them. RESULTS: In 7 out of 11 of cadavers, a final diagnosis of myocardial infarction was made after a complete autopsy and histology procedures. Isolated hearts underwent PMCTA scanning and was confirmed in 6/11 cases, with the autopsy findings showing the presence and the localization of occlusions or severe stenoses and the extension of the myocardial hypoxic area by the extravasation of contrast medium as well. CONCLUSION: Isolated single-organ PMCTA could be considered a valid and useful tool in addition to traditional autopsy investigation (macroscopic sections and histology) in identifying the cause of death by recognizing the presence and degree of coronary artery disease and myocardial infarction area visualization.

Evaluation of two methods for the use of diatoms in drowning cases.

In this study, we compare digestive methods used in a forensic context to extract diatoms (37 % hydrochloric acid) to a method recently described in Italian protocols for analysis of benthic diatoms for ecological assessment of surface water (hydrogen peroxide digestion). The two digestive methods were performed using 5 g of brain, lung, liver, kidney, and bone marrow taken from the bodies of 10 drowning victims recovered from three different aquatic environments (ocean, lakes, and rivers). Postmortem examination was performed on all bodies, but aquatic samples were only analyzed in two cases. Tissue digestion was equal by both methods. Hydrogen peroxide (H2O2) digestion resulted in better diatom preservation, enabling identification of nine genera in all samples examined versus three obtained using hydrochloride digestion. The ideal digestive method to provide evidence for corroboration of a diagnosis of drowning still needs to be established. However, the benthic diatoms protocol can be useful because it is less chemically hazardous to the laboratory operator and supports better diatom preservation for reliable taxonomic analysis.

Genetics of arrhythmogenic right ventricular cardiomyopathy.

Arrhythmogenic right ventricular cardiomyopathy is a rare clinical entity characterised by fibro-fatty replacement of myocardium, mainly involving right ventricular free wall, leading to malignant electrical instability and sudden cardiac death. The disease is inherited in up to 50% of cases, with incomplete penetrance and variable phenotypic expression. To date, more than 300 pathogenic mutations have been identified in 12 genes, mainly with autosomal dominant inheritance. Here, we focus on recent advances in the genetics of arrhythmogenic right ventricular cardiomyopathy. Despite continuous improvements, current genotype-phenotype studies have not contributed yet to establish a genetic risk stratification of the disease.

Loss-of-function KCNH2 mutation in a family with long QT syndrome, epilepsy, and sudden death.

There has been increased interest in a possible association between epilepsy channelopathies and cardiac arrhythmias, such as long QT syndrome (LQTS). We report a kindred that features LQTS, idiopathic epilepsy, and increased risk of sudden death. Genetic study showed a previously unreported heterozygous point mutation (c.246T>C) in the KCNH2 gene. Functional studies showed that the mutation induces severe loss of function. This observation provides further evidence for a possible link between idiopathic epilepsy and LQTS.

An unusual suicide: asphyxia by methane gas.

Asphyxia by suffocating gases, that is, methane or carbon dioxide, is characterized by the displacement of oxygen from inspired air. Thus, the cells are unable to receive oxygen and, as a consequence, are affected by acute hypoxemic hypoxia. The brain suffers because of the hypoxemic state, the subject become unconscious, and then, respiration arrest occurs, followed by cardiac arrest. This is the physiopathologic mechanism leading to death.We report a case of a 35-year-old man found dead at home with his mouth containing a tube linked to the domestic methane gas system originating from the wall, sealed with packing tape.

Comparative Impact Analysis of Low-Deductible Insurance Versus In-house Hospital Assumption of Risk and Management on Medical Malpractice Claims.

OBJECTIVES: Claims management is critical to ensure the safe and high-quality medical care for which liability insurers and/or hospitals are responsible. The aim of this research is to determine whether increasing hospital malpractice risk exposure, with increasing deductibles, has an impact on malpractice claims and payouts. METHODS: The study was conducted at a single tertiary hospital, the Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy. Payouts on closed reported and registered claims were analyzed during 4-study periods, which ranged from 1.5 million euro annual aggregate deductibles entirely managed by the insurance company to 5 million euro annual aggregate deductibles entirely managed by the hospital. We retrospectively analyzed 2034 medical malpractice claims submitted between January 1, 2007, and August 31, 2021. Four periods were examined depending on the claims management model adopted, ranging from total outsourcing to the insurer (period A) to an almost total hospital assumption of risk method (period D). RESULTS: We found that progressive hospital assumption of risk is associated with a decrease in the incidence of medical malpractice claims (average variation per year: -3.7%; P = 0.0029 if the 2 initial periods and the 2 last periods-characterized by the highest risk retention-are respectively aggregated and compared), an initial decrease in the mean claims cost followed by an increase that is still lower than the national increase (-5.4% on average), and an increase in the total claims cost (when compared with the period where the insurer solely managed claims). We also found that the rate of increase in payouts was less than the national average. CONCLUSIONS: The assumption of more malpractice risk by the hospital was associated with the adoption of numerous patient safety and risk management initiatives. The decrease in claims incidence could be due to the implementation of patient safety policies, while the cost increase could be attributed to inflation and rising costs of healthcare services and claims. Notably, only the hospital assumption of risk model with a high-deductible insurance coverage is sustainable for the studied hospital, while also being profitable for the insurer. In conclusion, as hospitals progressively assumed more risk and management responsibility of malpractice claims, there was a progressive decrease in the total number of claims, and a less rapid rise in claim payouts as compared with the national average. Even a small assumption of risk appeared to elicit meaningful changes in claim filings and payouts.

Discerning the ancestry of European Americans in genetic association studies.

European Americans are often treated as a homogeneous group, but in fact form a structured population due to historical immigration of diverse source populations. Discerning the ancestry of European Americans genotyped in association studies is important in order to prevent false-positive or false-negative associations due to population stratification and to identify genetic variants whose contribution to disease risk differs across European ancestries. Here, we investigate empirical patterns of population structure in European Americans, analyzing 4,198 samples from four genome-wide association studies to show that components roughly corresponding to northwest European, southeast European, and Ashkenazi Jewish ancestry are the main sources of European American population structure. Building on this insight, we constructed a panel of 300 validated markers that are highly informative for distinguishing these ancestries. We demonstrate that this panel of markers can be used to correct for stratification in association studies that do not generate dense genotype data.

Sudden cardiac death due to an anomalous posterior papillary muscle.

Anomalies of the mitral subvalvular apparatus can include differing types of papillary muscles and chordae tendinae. Direct insertion of the anomalous papillary muscle or chordae tendinea into the anterior mitral leaflet and fusion to the ventricular septum are common findings related to these anomalies. Anomalous papillary muscles or chordae, especially those that insert directly into the mitral leaflets, play a role in obstructing left ventricular outflow by restricting the mobility of the leaflets and/or tethering them toward the septum, thus narrowing the left ventricular outflow tract (LVOT). The incidence of mitral valve anomalies associated with LVOT is probably underestimated. This topic is frequently studied, however, especially in the pediatric cardiac surgery milieu, because LVOT obstruction could have a surgical solution. We report a case of an 18-year-old woman affected by epilepsy since 5 months of age who was found dead in her bedroom. An uncommon anomalous papillary muscle/chordae was the main autopsy finding. This malformation causes direct continuity between an accessory papillary muscle and a mitral leaflet, resulting in a long rigid area that can cause dynamic late-systolic intraleft-ventricular obstruction. In our case, in the absence of any other pathologic findings or major structural abnormalities, we speculate that a malignant cardiac arrhythmia provoked by the accessory papillary muscle could be the cause of death.

Decapitation due to car accident.

The occurrence of complete decapitation as a consequence of car accident is an extremely rare event. This fatality is generally seen in pedestrians run over by trains and also in motorcyclists who impact against the tailboard of trucks. Moreover, complete transection of pedestrians and occupants of cars has been described in road accidents especially in case of vehicles traveling at a high speed. We present a case of decapitation with complete degloving injury of the neck in a patient involved in a traffic accident, and we briefly discuss the possible mechanisms producing this injury.

State of the art in forensic investigation of sudden cardiac death.

The sudden death of a young person is a devastating event for both the family and community. Over the last decade, significant advances have been made in understanding both the clinical and genetic basis of sudden cardiac death. Many of the causes of sudden death are due to genetic heart disorders, which can lead to both structural (eg, hypertrophic cardiomyopathy) and arrhythmogenic abnormalities (eg, familial long QT syndrome, Brugada syndrome). Most commonly, sudden cardiac death can be the first presentation of an underlying heart problem, leaving the family at a loss as to why an otherwise healthy young person has died. Not only is this a tragic event for those involved, but it also presents a great challenge to the forensic pathologist involved in the management of the surviving family members. Evaluation of families requires a multidisciplinary approach, which should include cardiologists, a clinical geneticist, a genetic counselor, and the forensic pathologist directly involved in the sudden death case. This multifaceted cardiac genetic service is crucial in the evaluation and management of the clinical, genetic, psychological, and social complexities observed in families in which there has been a young sudden cardiac death. The present study will address the spectrum of structural substrates of cardiac sudden death with particular emphasis given to the possible role of forensic molecular biology techniques in identifying subtle or even merely functional disorders accounting for electrical instability.