Особенности развития и клинического течения пневмоторакса у больных новой коронавирусной инфекцией

New coronavirus infection (COVID-19) is a modern global problem that requires the rapid development of diagnostic and treatment methods, as well as the study of pathological effects on body tissues. Due to severe damage to the respiratory organs, special attention is paid to the study of pneumothorax as a manifestation of gas syndrome, one of the complications of COVID-19.The purpose of the study was to assess the incidence of pneumothorax as a complication of COVID-19, the features of the development of the pathological process, and to determine the criteria for treatment tactics.Materials and methods. In total, for the period from April 2020 to May 2022 at the Clinical Infectious Diseases Hospital named after. S.P. Botkin treated 31532 patients with a confirmed diagnosis of COVID-19. As part of this study, the case histories of 316 patients with clinical manifestations of gas syndrome were retrospectively analyzed. All patients were diagnosed with COVID-19, the diagnostic criterion of which was a positive result of the PCR test – the detection of RNA in a swab taken from the nasopharynx and oropharynx.Results. Analysis of case histories showed that severe COVID-19 occurs in all age groups. Collapse of half of the lung was observed in most cases (59 patients). The main treatment method for pneumothorax was Bulau drainage. At the same time, in 47 patients (32%) this method required active aspiration. In 37 patients (26%), drainage was corrected and the pleural cavity was re-drained. In 37 patients, the result of hospitalization was a fatal outcome, the main causes of which were severe pneumonia and/or severe immunodeficiency, 75 patients (52%) were discharged from the hospital in a stable condition.Conclusions. The occurrence of pneumothorax in patients with COVID-19 is characterized by late onset, protracted course, the formation of purulent complications and a high incidence of fatal outcomes, which do not always correlate with the severity of pneumonia.Новая коронавирусная инфекция – это современная глобальная проблема, требующая быстрой разработки методов диагностики и лечения, а также изучения патологического влияния на ткани организма. Вследствие выраженного повреждения органов дыхания особо важным представляется изучение пневмоторакса как проявления газового синдрома, одного из осложнений новой коронавирусной инфекции.Цель: оценить частоту встречаемости пневмоторакса как осложнения новой коронавирусной инфекции, особенности развития патологического процесса, а также определить критерии в лечебной тактике.Материалы и методы. Всего за период с апреля 2020 г. по май 2022 г. в Клинической инфекционной больнице им. С.П. Боткина пролечено 31 532 пациента с подтвержденным диагнозом новой коронавирусной инфекции. В рамках данного исследования ретроспективно проанализированы истории болезни 316 пациентов с клиническими проявлениями газового синдрома. У всех больных был выявлен COVID-19, диагностическим критерием которого являлся положительный результат ПЦР-теста – обнаружение РНК в мазке, взятом из носоглотки и ротоглотки.Результаты. Анализ историй болезни показал, что тяжелое течение новой коронавирусной инфекции встречается во всех возрастных группах. Коллабирование легкого на 1/2 наблюдалось в большей части случаев (59 пациентов). Основным методом лечения пневмоторакса является дренирование по Бюлау. При этом у 47 пациентов (32%) данный метод потребовал проведения активной аспирации. У 37 пациентов (26%) проведена коррекция дренажа и редренирование плевральной полости. У 37 пациентов итогом госпитализации стал летальных исход, основными причинами которого являлись тяжелое течение пневмонии и/или выраженный иммунодефицит, 75 пациентов (52%) были выписаны из стационара.Выводы. Возникновение пневмоторакса у больных с новой коронавирусной инфекции характеризуется поздним появлением, затяжным течением, формированием гнойных осложнений и высокой частотой летальных исходов, которые не всегда коррелируют с тяжестью течения пневмонии

UV-induced in-plane anisotropy in layers of mixture of the azo-dyes SD-1/SDA-2 characterized by spectroscopic ellipsometry

The optical properties of the azo-dyes SD-1/SDA-2, which are used for photoaligning of liquid crystals (LCs), are investigated with Variable Angle Spectroscopic Ellipsometry (VASE). Films of mixture of SD-1/SDA-2 are deposited by spin coating on silicon wafers. The estimated thickness is approximately 10 nm. To achieve photo-induced anisotropy, one of the samples is illuminated during 15 minutes with linearly polarized UV light followed by thermal stabilization during 1 hour at 150 °C. VASE measurements are performed in the wavelength range 200-1350 nm at several angles of incidence and at different sample orientations. Dielectric functions of azo-dye films without/with polarized UV light illumination were modelled using an ensemble of Lorentz oscillators. The results confirm the diffusion model proposed recently for explanation of the formation of the photo-induced order in azo-dye films under the action of polarized light. Refractive indices, their wavelength dispersion and thicknesses of films of SD-1/SDA-2 are reported here. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA

Liquid-crystal based light steering optical elements

Potential abilities of active optical elements based on liquid crystals are investigated. We consider liquid crystal cells in which a desired distribution of the liquid crystal director is achieved by a non-uniform electric field and by inhomogeneous boundary conditions. The optical elements built on principles of diffractive optics are discussed. © 2011 Photonics Society of Poland

Monochromatic bistable reflective and transfiective ferroelectric LCDs

We study single and double polarizer monochromatic bistable reflective and transfective direct view ferroelectric liquid crystal displays (FLCDs). Three types of monochromatic displays are considered Black & White, Black & Yellow, Black & Green. Theoretical approach for finding optimal parameters of an FLCD is presented

Characterization of the photo-alignment material SD-1/SDA-2 with spectroscopic ellipsometry

Variable angle spectroscopic ellipsometry (VASE) is applied for investigation of the azo-dye SD-1/SDA-2 which are used for photoalignment of liquid crystals. The azo-dye was spin coated on silicon substrates. Samples as prepared as well as samples illuminated with polarized UV light were studied. The measured optical constants were modelled with an ensemble of the Lorentz oscillators. The results confirm the reorientation mechanism of the photo-induced order formation in the azo-dye films under the action of polarized light, and also show that there exist some photochemical processes

Liquid crystal light deflecting devices based on nonuniform anchoring

Tunable liquid crystal light deflecting devices based on nonuniform anchoring energy are proposed. These devices have uniform thicknesses of the layers they are composed of, and beam deviation is controlled with a uniform electrical field. Potential applicability of such an approach in beam deflectors and active lenses is investigated. It is shown that the approach is a competitive alternative to liquid crystal light deflecting devices, in which the needed spatial distribution of liquid crystal molecules is achieved either due to nonuniform thickness or due to generation of nonuniform electrical field.Original Publication: Sergiy Valyukh, Iryna Valyukh, V Chigrinov, H S Kwok and Hans Arwin, Liquid crystal light deflecting devices based on nonuniform anchoring, 2010, APPLIED PHYSICS LETTERS, (97), 23, 231120. http://dx.doi.org/10.1063/1.3526311 Copyright: American Institute of Physics http://www.aip.org/</p

Liquid crystal light deflecting devices based on nonuniform anchoring

Tunable liquid crystal light deflecting devices based on nonuniform anchoring energy are proposed. These devices have uniform thicknesses of the layers they are composed of, and beam deviation is controlled with a uniform electrical field. Potential applicability of such an approach in beam deflectors and active lenses is investigated. It is shown that the approach is a competitive alternative to liquid crystal light deflecting devices, in which the needed spatial distribution of liquid crystal molecules is achieved either due to nonuniform thickness or due to generation of nonuniform electrical field. © 2010 American Institute of Physics