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Information × Registration Number 0217U001268, 0115U000475 , R & D reports Title The study of the mechanisms of formation of biological systems response and physical principles of new methods of medical micro- and macrodiagnosis. popup.stage_title Head Gorbenko Galyna Petrivna, Registration Date 02-02-2017 Organization Kharkov National University named after V.N. Karazin popup.description2 The objects of the study: oligomers and fibrils of lysozyme, fibrils of apolipoprotein A-I, hemoglobin, model lipid membranes of various composition. The goal of the study: - gaining insight into the modifying effects of oligomers and fibrils of lysozyme, as well as fibrillar mutants of 1-83 fragment of apolipoprotein A-I on the structure of lipid membranes of various composition and developing of a spectral characteristics model of the Doppler response in a tissues and complex biological systems with a variety of viscoelastic properties and their interface with the mechano-chemical processes. Methods of investigation: - fluorescence and absorption spectroscopy, fluorescence microscopy, computer modelling. Using the fluorescence probe technique the membranotropic activity of lysozyme oligomers has been investigated. The early oligomeric intermediates have been shown to exert the most pronounced effect on the structural state of model membranes, compared to the native protein. It has been demonstrated that lipid bilayer interactions of the aggregated protein produced the decrease of the membrane free volume and dehydration of the polar region. The association of oligomeric lysozyme with lipid membranes has been shown to be primarily governed by the hydrophobic interactions with the lipid acyl chains. The modifying effect of the monomers and fibrillar aggregates of lysozyme and 1-83 fragment of apolipoprotein A-I has been studied using the fluorescent probe pyrene. Amyloid lysozyme has been found to reduce the membrane free volume, while apolipoprotein A-I fibrils brought about the structural changes only in the cholesterol-containing membranes, evoking the free volume decrease and dehydration. The enhancement of the membrane effects of the lysozyme prefibrillar aggregates in the presence of hemoglobin has been revealed. The evaluation of the various stages of hepatic steatosis on the results of measurements of the attenuation coefficient in tissues was made. The measurements were made using the special measuring mode ultrasonic diagnostic scanner.An original algorithm to calculate the ultrasonic attenuation coefficient was developed. The algorithm is based on the analysis of ultrasonic amplitude response signals from different depths of tissue sensing ultrasonic pulses and applying an iterative procedure, which greatly improves the accuracy of calculations. Product Description popup.authors Є. Баранник І. Шеіна В. Трусова Г. Горбенко К. Вус О. Рижова С. Гірник С. Курилко popup.nrat_date 2020-04-02 Close