Histopathological evaluation of tissue undergoing thermal insult

Pathological alterations and COHb evaluations as tools for investigating fire-related deaths in veterinary forensic pathology

Fire-related deaths are usually a consequence of carbon monoxide (CO) poisoning or shock from thermal injuries. In humans, high levels of carboxyhemoglobin (COHb) concentrations in the blood can support a diagnosis of CO poisoning. In veterinary medicine, few studies investigated the pathological changes and blood COHb% in fire victims, and no data are available on post-mortem changes in blood gas composition due to fire. This study aims to investigate the pathological changes and COHb levels in both animal victims of fire and cadavers experimentally exposed to fire. For this purpose, dogs were selected and subdivided into three groups. Group A comprised 9 adult dogs, and Group B comprised 7 puppies that died under fire-related conditions. Group C was represented by 4 dog cadavers experimentally exposed to heat and smoke. A complete macroscopic, histological, and COHb evaluation were performed on each animal. Animals in Groups A and B showed cherry-red discoloration, thermal-injuries and soot deposits along the respiratory tract. Animals in Group C showed thermal injuries and soot deposits limited to the upper respiratory tract. The mean COHb% values in cadavers in Group C were lower than those observed in the other groups but higher compared to the values detected before the heat and smoke treatment. These findings suggest that both pathological changes and COHb analysis are valid tools for investigating fire-related deaths in dogs. However, the increase of COHb levels in cadavers exposed post-mortem to heat and smoke highlights how the COHb analysis should always be evaluated together with macroscopical and microscopical findings to avoid significant misjudgments in investigating fire-related fatalities in veterinary forensic practice.

Forensic Analysis and Identification Processes in Mass Disasters: Explosion of Gun Powder in the Fireworks Factory

A mass disaster is a situation that involves criticality between the number of victims and resources, in terms of both men and means, present on the site of an event that is mostly unexpected and sudden. In the multidisciplinary teams that intervene, the role of forensic pathologists, who are responsible for the direction and coordination of post-mortem operations, is central, and must remain so. The authors report the case of an explosion of a pyrotechnic artifice factory, as a result of which numerous victims and injuries are recorded. So, the team completed the autopsies and created a protocol to obtain biological samples (bones, blood, teeth, muscles), while the forensic pathologists contacted the families of the alleged victims and each provided a blood sample that was collected for the DNA. The geneticist, using the method of gene extraction and amplification, obtained the DNA from each bone, tooth, and muscle of blood taken from the victims and then compared it with that extracted from the blood samples of the relatives; the electropherograms showed at least one allele for each genetic marker of the "Combined DNA Index System" in common between the victims and the families, thus allowing to establish the identity of all the subjects involved in the event. Having established the identity of all workers, it was possible to determine their whereabouts in the environment at the time of the location of fires and explosions. The results of the various forensic analyzes (autopsies, genetic investigations and even traumatological investigations) have allowed us to validate a scientific method useful in all mass disasters even when any type of anthropological or forensic dental research is difficult.

Histological Studies on a Newly Isolated Bacillus subtilis D10 Protease in the Debridement of Burn Wound Eschars Using Mouse Model

Background: Proteases are among the most important industrial enzymes, playing a critical role in the physiological, biochemical, and regulatory processes of all living organisms. This study evaluated the histological effects of a Bacillus subtilis D10 protease in combination with the antibacterial ointment silver sulfadiazine (SSD) on the burned skin of mice. Materials and Methods: The bacterial proteolytic enzyme was produced and purified through DEAE-Sepharose CL-6B and Sephadex G-100 FF. The in vitro protease specificity was then determined. The dorsal skin of albino mice was burned with 80% HCl solution, then treated under three conditions: cold cream, SSD, and SSD combined with the tested protease. After 15 days of daily treatment, the mice were sacrificed and skin tissue samples were histopathologically examined using hematoxylin eosin, and Masson trichrome staining. Results: The D10 protease hydrolyzed the proteinaceous components of eschars (fibrin, normal collagen, and denatured collagen) in vitro. Mice skins treated with protease and SSD mixture showed promising results, with more rapid healing than the other treatments. This group regenerated epidermis and dermis with newly formed granulated follicles, fibroblasts and blood capillaries in the dermis, and collagen fibers in the hypodermis. Conclusions: These results suggest that the serine protease produced by B. subtilis D10 promotes wound healing of mice skin burnt with HCl and restores the normal architectural pattern in a shorter time than the standard treatments.

Safety of carotid artery stent in repetitive transcranial magnetic stimulation-The histopathological proof from swine carotid artery

INTRODUCTION

Repetitive transcranial magnetic stimulation (rTMS), including theta burst stimulation (TBS), is considered helpful for functional recovery in post-stroke patients. However, the safety is a common concern forusingr TMS for neuro-rehabilitation and research in patients with stents.

METHOD

Prolonged continuous theta burst stimulation (cTBS) with 1200 pulses at 50% of maximum output of Magstim Super Rapid2 was delivered in three different angles to a carotid stent placed in an isolated fresh swine carotid artery or on a table at a distance of 5cm. The possible migration and temperature change of the stent caused by cTBS was monitored by video recording and a digital thermometer, respectively. Histopathological study with hematoxylin and eosin stain were done on the vessel wall to identify possible micro thermal injury.

RESULTS

Stents in vessels did not cause any significant morphology change, such as thermal damage, after cTBS was given at three different angles. Neither visible migration nor significant temperature elevation was induced by cTBS.

CONCLUSION

There was no temperature change, thermal injury or migration after prolonged TBS at a high intensity, suggesting TBS is safe for clinical neuro-rehabilitation and physiological assessments in stroke patients with vascular stents.