The paper considers the possible mechanism of the pathogenesis of COVID-19 caused by SARS-COV-2, associated with damage to red blood cells, which the authors attribute to the main key target that triggers a cascade of reactions leading to multiple organ failure. The paper presents morphological evidence for the presence of pathological forms of erythrocytes characteristic of various anemias in the blood vessels and parenchyma of damaged lungs of patients with COVID-19. The death of red blood cells leads to cell ischemia and anemia. The defeat of brain neurons, blood vessels and hematotissue barriers in organ systems is a consequence of ischemia due to the impossibility of transferring hemoglobin by damaged erythrocytes and ends at the terminal stages of the development of the disease with their dysfunction. Adaptive erythropoiesis with an increase in erythropoietin secretion is especially dangerous for patients suffering from hypertension, and then it is impossible, since all organs involved in the synthesis of erythropoietin are damaged. In this case, the synthesis of hemoglobin is also disrupted due to a deficiency of iron and cyancobolamin, whereas toxic iron and hemosiderin are deposited in the tissues. K E y w o r d s-COVID-19, SARS-COV-2, erythrocytes, hemoglobin, erythropoiesis, viruses, pathogenesis of COVID-19.
The reactions of dermal structures to subcutaneous injections of gold nanoparticles were studied in CBA mice. Routes of the nanoparticles migration after injection and the mechanisms of their effects on the adjacent tissues were studied. Injected nanoparticles were phagocytosed by macrophages; some of them migrated to lymphoid follicles of the lymph node, while others migrated into blood vessels, where the particles were released from the macrophage cytoplasm into circulating blood. The endothelium was destroyed as a result of the toxic activity of macrophages loaded with nanoparticles. Two mechanisms of angiogenesis inhibition and death of blood vessels in tissues after injection of nanoparticles were distinguished. One mechanism consisted in deactivation of macrophages producing vascular endothelium growth factor inducing the formation of endothelium in the growing blood vessels, but not in direct inhibition of this factor. The other mechanism was realized through direct death of the endothelium in migration of macrophages through the vascular wall.
The effects of multiwalled carbon nanotubes on epitheliocytes of different compartments of the gastrointestinal tract and urothelium of different compartments of the renal nephron were studied in CBA mice. The nanotubes affected mouse gastrointestinal mucosa and renal urothelium. The cell reaction in the macula densa of the renal distal tubules and the immune system reaction to oral nanotubes were detected. A possible effect of nanotubes administered orally on the renal filtration function was hypothesized.
The review presents the characteristics of modern biocompatible and biodegradable wound dressings on the basis of seaweed polysaccharides (carrageenans of red algae, fucoidans and alginates of brown algae, ulvans of green algae) and notes the key physicochemical and biological properties that are important for constructing wounds dressings. There are information on various types of wound dressings and results of experimental and clinical tests of dressings in the treatment of wounds of various origins. Particular attention is paid to hydrogel dressings, since hydrogels meet the basic requirements for an ideal wound dressing, and many marine polysaccharides are able to form hydrogels.
The intensity of lymphocyte proliferation in response to pokeweed mitogen depends on cortisol level in the peripheral blood in the early post-traumatic period of penetrating eye injury. Lymphocyte proliferation in 72- and 96-h cultures from patients with high levels of endogenous hormone was suppressed. In 120-h cultures, the intensity of proliferation remains unchanged. Lymphocyte blast transformation was increased in 120-h cultures from patients with normal cortisol concentration and remained unchanged in case of low cortisol level.
Была изучена динамика процессов репаративной регенерации в ожоговой ране и в аутодермотрансплантате на фоне аутодермопластики, проводимой в разные сроки после термической травмы. Исследования проведены на 62 больных с дермальными ожогами III степени площадью от 10 до 20%, индекс Франка 30-60 ед. Морфологические изменения в ране в разные сроки после ожогов оценивали после окраски препаратов гематоксилин-эозином. Для количественной оценки регенераторного потенциала тканей ожоговой раны изучали экспрессию гена Ki-67. Проведена иммуногистохимическая идентификация иммунокомпетентных клеток (клеток Лангерганса, макрофагов, СD-4, CD-8). Пролиферативная активность клеток всех структур, формирующих ожоговую рану, а также эндотелия капилляров достигала максимума на 7-е сутки после травмы, а затем начинала снижаться. Максимальная плотность капилляров кожи на границе с раной также определялась на 7-8-е сутки. Эти сроки, согласно нашим клиническим, морфологическим и гистохимическим исследованиям, являются оптимальными для полного укрытия ожоговых ран. Активное хирургическое лечение включало раннюю некрэктомию и раннюю аутодермопластику. Наилучшие результаты лечения получены при завершении лечения в оптимальные сроки. При аутодермопластике, выполненной в поздние сроки, увеличивался процент лизиса пересаженной кожи, что было связано с нарушением репаративных процессов, патологическим ангиогенезом. Выявлено, что повышенная активность CD8+, макрофагов и клеток Лангерганса может приводить к неинфекционному разрушению трансплантата. Ключевые слова: термические ожоги, активное хирургическое лечение, локальный иммунный гомеостаз, макрофаги, клетки Лангерганса, CD4. CD8.
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