This study involves the histological analysis of samples taken during autopsies in cases of COVID-19 related death to evaluate the inflammatory cytokine response and the tissue localization of the virus in various organs. In all the selected cases, SARS-CoV-2 RT-PCR on swabs collected from the upper (nasopharynx and oropharynx) and/or the lower respiratory (trachea and primary bronchi) tracts were positive. Tissue localization of SARS-CoV-2 was detected using antibodies against the nucleoprotein and the spike protein. Overall, we tested the hypothesis that the overexpression of proinflammatory cytokines plays an important role in the development of COVID-19-associated pneumonia by estimating the expression of multiple cytokines (IL-1β, IL-6, IL-10, IL-15, TNF-α, and MCP-1), inflammatory cells (CD4, CD8, CD20, and CD45), and fibrinogen. Immunohistochemical staining showed that endothelial cells expressed IL-1β in lung samples obtained from the COVID-19 group (p < 0.001). Similarly, alveolar capillary endothelial cells showed strong and diffuse immunoreactivity for IL-6 and IL-15 in the COVID-19 group (p < 0.001). TNF-α showed a higher immunoreactivity in the COVID-19 group than in the control group (p < 0.001). CD8 + T cells where more numerous in the lung samples obtained from the COVID-19 group (p < 0.001). Current evidence suggests that a cytokine storm is the major cause of acute respiratory distress syndrome (ARDS) and multiple organ failure and is consistently linked with fatal outcomes.
In the last few years, predicting externally visible characteristics (EVCs) by adopting informative DNA molecular markers has become a method in forensic genetics that has increased its value, giving rise to an interesting field called “Forensic DNA Phenotyping” (FDP). The most meaningful forensic applications of EVCs prediction are those in which, having only a DNA sample isolated from highly decomposed remains, it is essential to reconstruct the physical appearance of a person. Through this approach, we set out to evaluate 20 skeletal remains of Italian provenance in order to associate them with as many cases of missing persons as possible. To achieve the intended goal, in this work we applied the HIrisPlex-S multiplex system through the conventional short tandem repeats (STR) method to confirm the expected identity of subjects by evaluating phenotypic features. To investigate the reliability and accuracy of the DNA-based EVCs prediction, pictures of the cases were compared as they were available to researchers. Results showed an overall prediction accuracy greater than 90% for all three phenotypic features—iris, hair, and skin colour—at a probability threshold of 0.7. The experimental analysis showed inconclusive results in only two cases; this is probably due to the characteristics of subjects who had an intermediate eye and hair colour, for which the DNA-based system needs to improve the prediction accuracy.
The study of aquaporins (AQPs) in various forensic fields has offered a promising horizon in response to the need to have reliable elements for the identification of the manner of death and for the individuation of forensic markers for the timing of lesions and vitality of injury. In the literature, various tissues have been studied; the most investigated are the lungs, brain, kidneys, skin, and blood vessels. A systematic literature review on PubMed following PRISMA 2020 guidelines enabled the identification of 96 articles. In all, 34 of these were enrolled to identify Aquaporin-like (AQP-like) forensic markers. The analysis of the literature demonstrated that the most significant markers among the AQPs are as follows: for the brain, AQP4, which is very important in brain trauma and hypoxic damage; AQP3 in the skin lesions caused by various mechanisms; and AQP5 in the diagnosis of drowning. Other applications are in organ damage due to drug abuse and thrombus dating. The focus of this review is to collect all the data present in the literature about the forensic application of AQPs as forensic markers in the most important fields of application. In the current use, the individuation, validation, and application of markers in forensic investigation are very useful in real forensic applications in cases evaluated in court.
During pregnancy, reactive oxygen species (ROS) serve as crucial signaling molecules for fetoplacental circulatory physiology. Oxidative stress is thought to sustain the pathogenesis and progression of hypoxic-ischemic encephalopathy (HIE). A retrospective study was performed on the brains and placentas of fetuses and newborns between 36–42 weeks of gestation (Group_1: Fetal intrauterine deaths, Group_2: Intrapartum deaths, Group_3: Post-partum deaths, Control group sudden neonatal death); all groups were further divided into two subgroups (Subgroup_B [brain] and Subgroup_P [placenta]), and the study was conducted through the immunohistochemical investigations of markers of oxidative stress (NOX2, 8-OHdG, NT, iNOS), IL-6, and only on the brain samples, AQP4. The results for the brain samples suggest that NOX2, 8-OHdG, NT, iNOS, and IL-6 were statistically significantly expressed above the controls. iNOS was more expressed in the fetal intrauterine death (Group_1) and less expressed in post-partum death (Group_3), while in intrapartum death (Group_2), the immunoreactivity was very low. IL-6 showed the highest expression in the brain cortex of the fetal intrauterine death (Group_1), while intrapartum death (Group_2) and post-partum death (Group_3) showed weak immunoreactivity. Post-partum death (Group_3) placentas showed the highest immunoreactivity to NOX2, which was almost double that of the fetal intrauterine death (Group_1) and intrapartum death (Group_2) placentas. Placental tissues of fetal intrauterine death (Group_1) and intrapartum death (Group_2) showed higher expression of iNOS than post-partum death (Group_3), while the IL-6 expression was higher in the fetal intrauterine death (Group_1) than the post-partum death (Group_3). The AQP4 was discarded as a possible marker because the immunohistochemical reaction in the three groups of cases and the control group was negative. The goal of this study, from the point of view of forensic pathology, is to provide scientific evidence in cases of medical liability in the Obstetric field to support the clinical data of the timing of HIE.
In the context of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, significant attention was given to pulmonary manifestations. However, cardiac involvement is increasingly recognized as a critical factor influencing the prognosis, leading to myocardial damage, heart failure, acute coronary syndromes, potentially lethal arrhythmic events, and sudden cardiac death. Despite these findings, there is a lack of studies detailing the necroscopic, macroscopic, and microscopic cardiac changes associated with SARS-CoV-2. This study aimed to investigate the presence of SARS-CoV-2 viral proteins in cardiac tissue using immunohistochemical techniques to assess viral tropism. The analysis of cardiac tissue samples from deceased subjects, in different stages of conservation, confirmed to be positive for SARS-CoV-2 via reverse transcriptase-polymerase chain reaction (RT-PCR), showed immunopositivity for the SARS-CoV-2-NP viral antigen in 33% of cases. Notably, the presence of leukocyte infiltrates sufficient for diagnosing lymphocytic myocarditis was not observed. The central proinflammatory cytokines involved in the pathogenetic mechanism of coronavirus disease 19 (COVID-19) were researched using the immunohistochemical method. A significant increase in cytokine expression was detected, indicating myocardial involvement and dysfunction during SARS-CoV-2 infection. These findings suggest that the immunohistochemical detection of SARS-CoV-2 viral antigens and inflammatory cytokine expression in cardiac tissue could be crucial for a proper forensic assessment of the cause of death, even in sudden cardiac death.
Background: Intrauterine fetal death and perinatal death represent one of the most relevant medical scientific problems since, in many cases, even after extensive investigation, the causes remain unknown. The considerable increase in medical legal litigation in the obstetrical field that has witnessed in recent years, especially in cases of stillborn births, has simultaneously involved the figure of the forensic pathologist in scientific research aimed at clarifying the pathophysiological processes underlying stillbirth. Methods: our study aims to analyze cases of sudden intrauterine unexplained death syndrome (SIUD) to evaluate the role of oxidative stress in the complex pathogenetic process of stillbirth. In particular, the immunohistochemical expression of specific oxidative stress markers (NOX2, NT, iNOS, 8-HODG, IL-6) was evaluated in tissue samples of placentas of SIUDs belonging to the extensive case series (20 cases), collected from autopsy cases of the University of Ferrara and Politecnica delle Marche between 2017 and 2023. Results: The study demonstrated the involvement of oxidative stress in intrauterine fetal deaths in the placenta of the cases examined. In SIUD, the most expressed oxidative stress markers were NOX2 and 8-HODG. Conclusions: The study contributes to investigating the role of oxidative stress in modulating different pathways in unexplained intrauterine fetal death (SIUD) tissues.