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Introduction The estimation of post-mortem interval (PMI) remains a major challenge in forensic science. Most of the proposed approaches lack the reliability required to meet the rigorous forensic standards. Objectives We applied 1H NMR metabolomics to estimate PMI on ovine vitreous humour comparing the results with the actual scientific gold standard, namely vitreous potassium concentrations. Methods Vitreous humour samples were collected in a time frame ranging from 6 to 86 h after death. Experiments were performed by using 1H NMR metabolomics and ion capillary analysis. Data were submitted to multivariate statistical data analysis. Results A multivariate calibration model was built to estimate PMI based on 47 vitreous humour samples. The model was validated with an independent test set of 24 samples, obtaining a prediction error on the entire range of 6.9 h for PMI < 24 h, 7.4 h for PMI between 24 and 48 h, and 10.3 h for PMI > 48 h. Time-related modifications of the 1H NMR vitreous metabolomic profile could predict PMI better than potassium up to 48 h after death, whilst a combination of the two is better than the single approach for higher PMI estimation. Conclusion The present study, although in a proof-of-concept animal model, shows that vitreous metabolomics can be a powerful tool to predict PMI providing a more accurate estimation compared to the widely studied approach based on vitreous potassium concentrations.

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.

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.

Methiopropamine is a structural analog of methamphetamine that is categorized as a novel psychoactive substance. It primarily acts as a norepinephrine–dopamine reuptake inhibitor and, secondarily, as a serotonin reuptake inhibitor. In humans, methiopropamine induces stimulation and alertness and increases focus and energy. However, significant side effects are reported, such as tachycardia, anxiety, panic attacks, perspiration, headache, and difficulty in breathing. To date, little data is available regarding its pharmacodynamic effects, thereby we aimed to investigate the acute in vivo effects induced by this drug on sensorimotor responses, body temperature, pain thresholds, motor activity, and cardiovascular and respiratory systems in CD-1 male mice. We selected a range of doses that correspond to the whole range of human reported use, in order to evaluate the threshold of adverse effects presentation. This study demonstrates that methiopropamine acts as a dopaminergic and noradrenergic stimulating drug and that the highest doses (10–30 mg/kg) impair the visual placing response, facilitate the acoustic and tactile response, induce hypothermia, increase mechanical and thermal analgesia, stimulate locomotor activity, induce motor stereotypies, and strongly affected cardiovascular and respiratory parameters, increasing heart rate, breath rate, and blood pressure but reducing oxygen saturation. On the contrary, lower doses do not show any of those effects. We hypothesize that there is a range of doses that do enhance performance but do not seem hazardous to users: this gap could induce the perception of safety and increase the abuser population.

MDPV is a synthetic cathinone illegally marketed and consumed for its psychostimulant effects, which are similar to those produced by cocaine, amphetamines, and MDMA. Clinical reports indicate that MDPV produces euphoria, increases alertness, and at high doses causes agitation, psychosis, tachycardia and hypertension, hallucinations, delirium, hyperthermia, rhabdomyolysis, and even death. In rodents, MDPV reproduces the typical physiological effects of psychostimulant drugs, demonstrating greater potency than cocaine. Nevertheless, its role in aggressive behavior has been reported but not yet experimentally confirmed. Therefore, the aim of this study was to evaluate the effects of acute and repeated MDPV (0.01-10 mg/kg i.p.) administration on aggressive behavior in mice and to compare them with those of cocaine (0.01-10 mg/kg i.p.) administration. To this purpose, the resident-intruder test in isolated mice and the spontaneous and stimulated aggressiveness tests for group-housed mice were employed. The present study shows for the first time that MDPV enhances aggressive behavior and locomotion in mice with greater potency and efficacy than cocaine treatment. Moreover, the aggressive and locomotor responses are enhanced after repeated administration, indicating that a sensitization mechanism comes into play. These results, although from preclinical investigation, are suggestive that human MDPV intake could be a problem for public health and the criminal justice system. Thus, investigation by police officers and medical staff is needed to prevent interpersonal violence induced by the consumption of synthetic cathinones.

When a sudden death occurs during a minor surgical intervention, it may require a careful and extensive postmortem investigation. One such case concerns a 61-year-old male patient affected by Peyronie's disease, who died suddenly during a corporoplasty procedure. Autopsy and histologic examinations showed a massive bilateral pulmonary micro-embolism brought on by periprostatic venous plexus thrombosis. The cause of death was attributed to intraoperative fatal pulmonary micro-embolism. Pulmonary thromboembolism is a major cause of death and is known to be a possible complication of surgery. Nevertheless, the periprostatic venous plexus is an unusual site of thrombosis, as it has been demonstrated that the majority of emboli originate in the legs. In this case, the embolism was massive and fatal and occurred during a minor surgical procedure, even though the patient was not at risk for venous thromboembolism, nor did he have a significant past medical history.

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.

We report a case of a 6-year-old boy who had been living with his parents, both cocaine smokers, and who was urgently admitted to hospital for general distress. Upon examination, cocaine and cocaine metabolites were detected in hair and urine samples. These toxicological findings most likely indicate that the child had passively consumed the drug when living in a heavily contaminated environment.