S100B protein expression in the heart of deceased individuals by overdose: a new forensic marker?

OBJECTIVE: The evaluation of S100B protein expression in the human heart and its correlation with drug-related death. METHOD: Left ventricular samples were collected from 74 serial forensic autopsies (15 overdose-related deaths; 59 non-overdose-related deaths) from 2007 to 2010. Tissue sections from each sample were immunostained for S100B protein by a commercial antibody. RESULTS: The S100B protein was detected in the heart samples of all 15 cases of drug-related deaths; S100B immunoreactivity was mainly observed in the cytoplasm of cardiomyocytes and as globular deposits in the interstitial spaces. No reactivity or weak reactivity was found in the cardiomyocytes of the 59 subjects who died of other causes. CONCLUSION: Our preliminary data show that the S100B protein accumulates in injured cardiomyocytes during drug-related sudden death. Given the near absence of S100B protein in the heart of subjects who died from causes other than drug overdose, S100B immunopositivity may be used as a new ancillary screening tool for the postmortem diagnosis of overdose-related cardiac death

Hypoxia/reoxygenation-induced myocardial lesions in newborn piglets are related to interindividual variability and not to oxygen concentration

OBJECTIVE: Evaluation of myocardial histological changes in an experimental animal model of neonatal hypoxiareoxygenation. METHODS: Normocapnic hypoxia was induced in 40 male Landrace/Large White piglets. Reoxygenation was initiated when the animals developed bradycardia (HR <60 beats/min) or severe hypotension (MAP <15 mmHg). The animals were divided into four groups based on the oxygen (O2) concentration used for reoxygenation; groups 1, 2, 3, and 4 received 18%, 21%, 40%, and 100% O2, respectively. The animals were further classified into five groups based on the time required for reoxygenation: A: fast recovery (<15 min); B: medium recovery (15-45 min); C: slow recovery (45-90 min); D: very slow recovery (>90 min), and E: nine deceased piglets. RESULTS: Histology revealed changes in all heart specimens. Interstitial edema, a wavy arrangement, hypereosinophilia and coagulative necrosis of cardiomyocytes were observed frequently. No differences in the incidence of changes were observed among groups 1-4, whereas marked differences regarding the frequency and the degree of changes were found among groups A-E. Coagulative necrosis was correlated with increased recovery time: this condition was detected post-asphyxia in 14%, 57%, and 100% of piglets with fast, medium, and slow or very slow recovery rates, respectively. CONCLUSIONS: The significant myocardial histological changes observed suggest that this experimental model might be a reliable model for investigating human neonatal cardiac hypoxia-related injury. No correlation was observed between the severity of histological changes and the fiO2 used during reoxygenation. Severe myocardial changes correlated strictly with recovery time, suggesting an unreported individual susceptibility of myocardiocytes to hypoxia, possibly leading to death after the typical time-sequence of events

Stem cell markers in the heart of the human newborn

The identification of cardiac progenitor cells in mammals raises the possibility that the human heart contains a population of stem cells capable of generating cardiomyocytes and coronary vessels. Several recent studies now show that the different cell types that characterize the adult human heart arise from a common ancestor. Human cardiac stem cells differentiate into cardiomyocytes, and, in lesser extent, into smooth muscle and endothelial cells. The characterization of human cardiac stem cells (CSCs) has important clinical implications. In recent years, CD117 (c-kit) has been reported to mark a subtype of stem/progenitor cells in the human heart, with stem cell-like properties, including the ability to self-renewal and clonogenicity multipotentiality.   Proceedings of the 2nd International Course on Perinatal Pathology (part of the 11th International Workshop on Neonatology · October 26th-31st, 2015) · Cagliari (Italy) · October 31st, 2015 · Stem cells: present and future Guest Editors: Gavino Faa, Vassilios Fanos, Antonio Giordan

Perinatal cardiac failure from the eyes of the pathologist

Cardiac abnormalities in neonates are often underdiagnosed and require an high index of suspicion by the perinatal pathologist. Perinatal conditions, such as preterm birth, infection and asphyxia can affect newborn health and disease, and in particular may cause relevant pathological changes in the cardiovascular system. On the basis of our experience on the histological study of the neonatal heart, endothelial damage represents a diffuse pathological feature in the myocardial vessels of newborns subjected to perinatal hypoxia. Endothelial cell swelling, apoptosis, detachment and microthrombosis are the most frequent lesions observed in the neonatal heart. In cases of severe vascular changes associated with disseminated intravascular coagulation (DIC), cardiomyocyte apoptosis and coagulative necrosis represent the histological marker of cardiac pathology in the neonatal heart. A new and very sensitive early tool to identify cardiac changes in perinatal period is represented by immunoreactivity of cardiac cells for S100B protein. Immunostaining for S100B protein in the neonatal heart might indicate an early protective reaction of cardiomyocytes in newborns subjected to asphyxia, clearly indicating a chronic or sub-acute evolution of the clinical picture, and contrasting with the hypothesis of a sudden death. In conclusions, our data shows that the perinatal pathologist represents a pivotal figure in the early study and detection of cardiac changes in all neonates, particularly in newborns undergoing asphyxia in the perinatal period.   Proceedings of the International Course on Perinatal Pathology (part of the 10th International Workshop on Neonatology · October 22nd-25th, 2014) · Cagliari (Italy) · October 25th, 2014 · The role of the clinical pathological dialogue in problem solving Guest Editors: Gavino Faa, Vassilios Fanos, Peter Van Eyke

Hypoxia-Induced Endothelial Damage and Microthrombosis in Myocardial Vessels of Newborn Landrace/Large White Piglets

Objective. Evaluating the presence of endothelial changes in myocardial vessels in an experimental model of hypoxia and resuscitation in newborn piglets. Methods. Fifty male Landrace/Large White neonatal piglets were studied: ten of them were allocated in group A (control group, SHAM-operated). In group B (forty animals, experimental group) normocapnic hypoxia was induced by decreasing inspired concentration of O2 to 6%–8%. When the animals developed bradycardia or severe hypotension, reoxygenation was initiated. The animals of group B were allocated in 4 subgroups of 10, according to the concentration of O2 they were resuscitated with (groups 1, 2, 3, and 4 received 18%, 21%, 40%, and 100% O2, resp.). Results. Control group animals did not show any significant endothelial lesions. Contrarily, endothelial lesions were detected in all experimental group cases. When these lesions were analyzed in the different heart zones, no significant difference in their incidence was observed; analyzing the frequency in the animals of the 4 subgroups, only microthrombosis showed a higher frequency in animals in groups 4 and 3. Conclusions. Endothelial damage represents a diffuse pathological feature in the myocardial vessels of piglets subjected to normocapnic hypoxia and resuscitation suggesting a possible role of hyperoxygenation in aggravating endothelial damage

Hypoxia-Induced Endothelial Damage and Microthrombosis in Myocardial Vessels of Newborn Landrace/Large White Piglets

Objective. Evaluating the presence of endothelial changes in myocardial vessels in an experimental model of hypoxia and resuscitation in newborn piglets. Methods. Fifty male Landrace/Large White neonatal piglets were studied: ten of them were allocated in group A (control group, SHAM-operated). In group B (forty animals, experimental group) normocapnic hypoxia was induced by decreasing inspired concentration of O 2 to 6%-8%. When the animals developed bradycardia or severe hypotension, reoxygenation was initiated. The animals of group B were allocated in 4 subgroups of 10, according to the concentration of O 2 they were resuscitated with (groups 1, 2, 3, and 4 received 18%, 21%, 40%, and 100% O 2 , resp.). Results. Control group animals did not show any significant endothelial lesions. Contrarily, endothelial lesions were detected in all experimental group cases. When these lesions were analyzed in the different heart zones, no significant difference in their incidence was observed; analyzing the frequency in the animals of the 4 subgroups, only microthrombosis showed a higher frequency in animals in groups 4 and 3. Conclusions. Endothelial damage represents a diffuse pathological feature in the myocardial vessels of piglets subjected to normocapnic hypoxia and resuscitation suggesting a possible role of hyperoxygenation in aggravating endothelial damage

Hypoxia-Induced Endothelial Damage and Microthrombosis in Myocardial Vessels of Newborn Landrace/Large White Piglets

Objective. Evaluating the presence of endothelial changes in myocardial vessels in an experimental model of hypoxia and resuscitation in newborn piglets. Methods. Fifty male Landrace/Large White neonatal piglets were studied: ten of them were allocated in group A (control group, SHAM-operated). In group B (forty animals, experimental group) normocapnic hypoxia was induced by decreasing inspired concentration of O-2 to 6%-8%. When the animals developed bradycardia or severe hypotension, reoxygenation was initiated. The animals of group B were allocated in 4 subgroups of 10, according to the concentration of O-2 they were resuscitated with (groups 1, 2, 3, and 4 received 18%, 21%, 40%, and 100% O-2, resp.). Results. Control group animals did not show any significant endothelial lesions. Contrarily, endothelial lesions were detected in all experimental group cases. When these lesions were analyzed in the different heart zones, no significant difference in their incidence was observed; analyzing the frequency in the animals of the 4 subgroups, only microthrombosis showed a higher frequency in animals in groups 4 and 3. Conclusions. Endothelial damage represents a diffuse pathological feature in the myocardial vessels of piglets subjected to normocapnic hypoxia and resuscitation suggesting a possible role of hyperoxygenation in aggravating endothelial damage

Multiple organ failure syndrome in the newborn: morphological and immunohistochemical data

Multiple organ failure (MOF) syndrome, also known as multiple organ dysfunction syndrome (MODS) represents a common but complex problem in critically ill patients in neonatal intensive care unit (NICU) centers, and a major cause of morbidity and mortality in newborns. MOF is considered the result of an inappropriate generalized inflammatory response of the newborn to a variety of acute insults. This study was aimed at analyzing, at histology, multiple organ pathological changes in two newborns admitted to the NICU center of our University Hospital, who showed a progressive clinical picture of MOF, in order to verify the pathological changes of vascular structures and of endothelial cells in the different organs affected by MOF. All the samples obtained at autopsy for histological examination showed specific organ pathological changes, especially related to modifications in vascular structures and, in particular, in endothelial cells. The most interesting findings were found in the intestinal barrier, in the lower respiratory tract and in the endothelial barrier. The loss of the gut barrier could allow the passage into the blood of microbial factors that could trigger the production of tumor necrosis factor alpha (TNF alpha) leading to endothelial damage. Our preliminary study underlines the principal role probably played by intestinal and vascular changes in the origin of MOF in newborns