Temperature Effect on Exciton Absorption of CuBr Nanocrystals in Potassium-aluminaborate Glass

The paper describes the research of temperature effect of potassium-alumina-borate (PAB) glass with CuBr nanocrystals, which was obtained in optical wavelength region for the first time. Temperature dependence of optical density at different wavelengths was examined. Melting and crystallization temperatures were evaluated for different nanocrystals sizes. Great changes of exciton absorption band influenced by temperatures below 100°C were recorded. Propositions for studied glass application as tunable filters in electro-optic circuit were suggested. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3542

Brain morphological changes in covid-19

The aim of the study was to identify the pathomorphology of brain damage in patients who died of COVID-19. Material and methods. Autopsy reports and autopsy brain material of 17 deceased patients with pre-mortem confirmed COVID-19 infection were analyzed. Fatal cases in which COVID-19 was the major cause of death were included in the study. Five people were diagnosed with cerebral infarction. Organ samples were taken for histological examination during autopsy. Sections were stained with hematoxylin and eosin and by Nissl to assess brain histopathology. To study the vascular basal membranes the PAS reaction was used, to detect fibrin in vessels phosphotungstic acid-hematoxylin (PTAH) staining was used, to determine DNA in nuclei sections were stained according to Feulgen, to detect RNA in neuronal nuclei and cytoplasm sections were stained with methyl green-pyronin. Immunohistochemical study of a neuronal marker, nuclear protein NeuN, was performed to assess neuronal damage. Results. The signs of neuronal damage found in patients who died of COVID-19 included nonspecific changes of nerve cells (acute swelling, retrograde degeneration, karyolysis and cytolysis, ‘ghost' cells, neuronophagia and satellitosis) and signs of circulatory disorders (perivascular and pericellular edema, diapedesis, congested and engorged microvasculature). Conclusion. Brain histopathological data indicate damage to the central nervous system in COVID-19 patients. Ischemic stroke in patients with COVID-19 is mostly caused by a combination of hypoxia resulting from respiratory failure and individual risk factors, including cerebrovascular atherosclerosis and hypertension. © 2021, V.A. Negovsky Research Institute of General Reanimatology. All rights reserved

The Role of Von Willebrand Factor in the Pathogenesis of Pulmonary Vascular Thrombosis in COVID-19

The increased plasma levels of von Willebrand factor (VWF) in patients with COVID-19 was reported in many studies, and its correlation with disease severity and mortality suggest its important role in the pathogenesis of thrombosis in COVID-19. We performed histological and im-munohistochemical studies of the lungs of 29 patients who died from COVID-19. We found a sig-nificant increase in the intensity of immunohistochemical reaction for VWF in the pulmonary vascular endothelium when the disease duration was more than 10 days. In the patients who had thrombotic complications, the VWF immunostaining in the pulmonary vascular endothelium was significantly more intense than in nonsurvivors without thrombotic complications. Duration of disease and thrombotic complications were found to be independent predictors of increased VWF im-munostaining in the endothelium of pulmonary vessels. We also revealed that bacterial pneumonia was associated with increased VWF staining intensity in pulmonary arterial, arteriolar, and venular endothelium, while lung ventilation was an independent predictor of increased VWF immunostain-ing in arterial endothelium. The results of the study demonstrated an important role of endothelial VWF in the pathogenesis of thrombus formation in COVID-19. © 2022 by the authors. Lcensee MDPI, Basel, Switzerland

ОТДАЛЕННЫЕ РЕЗУЛЬТАТЫ ЛЕЧЕНИЯ БОЛЬНЫХ САРКОМАМИ КОСТЕЙ С УЧЕТОМ СОДЕРЖАНИЯ МЕТАЛЛОПРОТЕИНАЗ В СЫВОРОТКЕ КРОВИ

Background: Bone sarcomas are extremely malignant prone to rapid hematogenic metastasing. Evaluation of biological marker expression by the tumor is important not only for the search of new potential chemotherapy targets, but for the assessment of the disease prognosis.Aim: A comparative evaluation of matrix metalloproteinases (MMP)-2, -7, -9 and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the serum of patients with primary bone tumors and in healthy people to identify their potential association with the histological characteristics of the tumor and the disease prognosis.Materials and methods: A comparative study of serum MMP-2, -7, -9, and TIMP-1 levels was performed in 54 patients with primary bone tumors (malignant, 45 patients, including central osteosarcoma in 21, periosteal osteosarcoma in 4, Ewing's sarcoma in 11, primary chondrosarcoma in 6, undifferentiated pleomorphic sarcoma in 3, and borderline giant cell tumors in 9) and in 26 healthy individuals with the use of the immunoenzyme technique (Biosource, USA, for TIMP-1 and RD, USA, for MMP-2, -7, and -9). Results: The TIMP-1 levels in the serum of patients with central and periosteal osteosarcomas were significantly higher than in the serum of healthy controls (р = 0.038 and p = 0.007, respectively). The MMP-9 levels in patients with bone malignancies were significantly lower than that in the normal controls (p 0.05). There was a positive correlation between serum TIMP-1 and MMP-9 levels in patients with central, periosteal and Ewing's sarcomas (r = 0.37, p = 0.024). No significant differences in the 5-year survival rates related to serum TIMP-1, MMP-2, -7, -9 levels were found in patients with bone sarcomas. However, in those with osteosarcoma and serum MMP-2 160 ng/ml, the overall 5-year survival rate was 1.6-fold higher than in those with lower MMP-2 levels, and in those with ММP-9 levels 377 ng/ml, the 5-year survival rate was 1.4-fold higher than in patients with ММP- 9 377 ng/ml. The worst 5-year survival (33%) was found in the patients with serum ММP-2 levels of less than 160 ng/ml and ММP-9 of more than 377 ng/ml. Conclusion: The results obtain suggest that the expression of MMP-2, MMP-9 and TIMP-1 could be associated with pathophysiological changes related to growth and metastatic process of bone sarcomas and osteosarcoma, in particular. This area could be an object for further studies on levels of these biomarkers and their prognostic value in bone malignancies.Актуальность. Саркомы костей – чрезвычайно злокачественные опухоли, склонные к быстрому гематогенному метастазированию. Изучение экспрессии опухолями биологически активных веществ актуально не только для поиска новых потенциальных мишеней химиотерапии, но и в оценке прогноза заболевания.Цель – сравнительное изучение содержания матриксных металлопротеиназ (ММП)-2, -7, -9 и их тканевого ингибитора ТИМП-1 в сыворотке крови больных первичными злокачественными новообразованиями костей и практически здоровых людей для выявления их возможной взаимосвязи с гистологическим строением опухоли и прогнозом заболевания.Материал и методы. Проведено сравнительное изучение содержания ММП-2, -7, -9 и ТИМП-1 в сыворотке крови 54 больных первичными опухолями костей (злокачественные опухоли отмечены у 45 пациентов: типичная остеосаркома (n = 21), периостальная остеосаркома (n = 4), саркома Юинга (n = 11), первичная хондросаркома (n = 6), недифференцированная плеоморфная саркома (n = 3); пограничные – гигантоклеточная опухоль кости – у 9) и 26 условно здоровых людей иммуноферментным методом с помощью реактивов “Biosource” (США) для ТИМП-1 и “RD” (США) для ММП-2, ММП-7, ММП-9.Результаты. Уровни ТИМП-1 при типичной остеосаркоме и периостальной остеосаркоме были достоверно выше, чем у практически здоровых людей (р = 0,038 и p = 0,007 соответственно). Содержание ММП-9 при злокачественных опухолях костей было достоверно ниже, чем у практически здоровых людей (p 0,05). Выявлена прямая корреляция между содержанием ТИМП-1 и ММП-9 в сыворотке крови при типичной остеосаркоме, периостальной остеосаркоме и саркоме Юинга (r = 0,37, p = 0,024). Достоверных различий в показателях общей 5-летней выживаемости при саркомах костей, в частности, при остеосаркоме, с учетом содержания ТИМП-1 и ММП-2, -7, -9 в сыворотке крови не выявлено. Однако при остеосаркоме общая 5-летняя выживаемость при содержании ММП-2 160 нг/мл в сыворотке крови была в 1,6 раза выше, чем при более низких значениях ММП-2, а при ММП-9 377 нг/мл – в 1,4 раза выше, чем при ММП-9 377 нг/мл. Минимальные показатели общей 5-летней выживаемости (33%) выявлены у пациентов с уровнями протеиназ ММП-2 160 нг/мл и ММП-9 377 нг/мл.Заключение. Полученные данные позволяют предположить, что экспрессия ММП-2, ММП-9 и ТИМП-1 может иметь связь с патогенетическими изменениями, связанными с ростом и метастазированием сарком костей, в частности, остеосаркомы, и может служить предметом дальнейших исследований по определению уровней этих показателей и их значения в прогнозе злокачественных новообразований костей