[Features of expression of GLUT-1 and Ki-67 proteins in various components of mixed variants of ameloblastoma]. / Osobennosti ekspressii belkov GLUT-1 i Ki-67 v razlichnykh komponentakh smeshannykh variantov ameloblastomy.

THE AIM OF THE STUDY: The aim was to study the metabolic and proliferative activity of the components of ameloblastoma of mixed histological structure. To assess the impact of individual components of mixed variants of ameloblastoma on treatment results and the risk of relapse. MATERIAL AND METHODS: The study included 21 histological specimens of mixed ameloblastoma. To study proliferative and metabolic activity, histological preparations were immunohistochemically stained. To assess the proliferation of tumor components, histological preparations were stained for the presence of antigens to Ki-67, and the level of metabolic activity was assessed by the expression level of the glucose transporter GLUT-1. Statistical analysis was performed using the Mann-Whitney test, statistical significance was determined using the Chi-square test, and correlation analysis was performed using Spearman's. RESULTS: Among the samples of mixed ameloblastoma included in the study, a non-uniform distribution of proliferation and intensity of metabolic activity among the components was obtained. So, among all the components, the plexiform and basal cell variants are distinguished by the greatest proliferative activity. The metabolic activity of these components of mixed ameloblastoma is also increased. CONCLUSIONS: The data obtained allow us to conclude that it is necessary to take into account plexiform and basal cell components of mixed ameloblastoma, as this can affect the effectiveness of treatment and the risk of relapse.

[Organ changes found by postmortem examination in COVID-19 patients]. / Izmeneniya organov, vyyavlennye pri posmertnom issledovanii patsientov s COVID-19.

The postmortem study results presented in 20 sources of literature on 186 COVID-19 patients were analyzed. Pathological changes were noted in multiple organs, by involving predominantly the respiratory, circulatory, and excretory systems. The changes in the lungs were characterized by an increase in organ weight (59.3%), a dark red color of the parenchyma (47.4%), compaction of lung tissue (56%), and signs of lung congestion (37.3%). The histological characteristics found during postmortem lung tissue examination, which were indicative of diffuse alveolar damage, were proliferation of type II alveolocytes in 65.2% of cases, the appearance of hyaline membranes lining the alveoli in 64.4%, and interstitial edema in 54.2%. In the analyzed sources, 22% of cases were noticed to have severe thrombosis and pulmonary artery branch embolism that was associated with lower extremity deep vein thrombosis. In all the sources of literature, acute tubular necrosis, tubular luminal dilatation, and interstitial edema were detected in the kidneys.

[The proliferative activity of tumor cells and the distribution of SOX2+ pluripotent stem cells in various histological types of ameloblastoma]. / Proliferativnaia aktivnost' kletok opukholi i raspredelenie SOX2+ pliuripotentnykh stvolovykh kletok v razlichnykh gistologicheskikh variantakh ameloblastomy.

AIM: to investigate the proliferative activity and distribution of pluripotent stem cells in various histological types of amelobrastoma. MATERIAL AND METHODS: The surgical and archival materials of 76 patients with ameloblastoma from the Central Research Institute of Dentistry and Oral Surgery, Ministry of Health of the Russian Federation, were used. Tissue antigens were determined using a rabbit monoclonal antibody against to Ki-67 and SOX2. RESULTS: Proliferating (Ki-67) and pluripotent (SOX2) cells were identified in various histological types of ameloblastoma. A weak significant correlation was found between tumor size, pluripotent stem cells, and cellular proliferative activity. Enhanced cell proliferative activity and extensive bone tissue destruction significantly correlated with the development of recurrent ameloblastoma. CONCLUSION: The presence of pluripotent stem cells, the proliferative activity of ameloblastoma cells, and the extensiveness of bone tissue destruction allow basal-cell and plexiform options to be considered as the most aggressive indicators.

[The role of Wnt/ß-catenin signaling pathway in ameloblastoma formation]. / Rol' Wnt/ß-kateninsignal'nogo puti v formirovanii ameloblastomy.

The aim of the study was to assess the role of the canonical Wnt/ß-catenin signaling pathway in the formation and clinical course of various histological variants of ameloblastoma. MATERIAL AND METHODS: 76 cases of ameloblastoma were investigated, the average age of the patients was 46 years. There were 49 (64.5%) cases of recurrence of the disease. Tissue antigens were determined using monoclonal rabbit antibodies to Ki-67 and ß-catenin. RESULTS: it was found correlation between the proliferative activity of ameloblastoma cells and the intranuclear localization of ß-catenin, indicating the activation of the Wnt/ß-catenin-signaling pathway. It was shown that the nuclear localization of ß-catenin is positively correlated with the recurrence. CONCLUSION: The Wnt/ß-catenin signaling pathway is involved in a formation and progression of ameloblastoma.