Dynamics of endothelial function indexes in patients with post-Covid syndrome using a combination drug of ethylmethylhydroxyperidine succinate/vitamin B6

Aim: to evaluate endothelial function in patients after COVID-19 before and after treatment with combination drug of ethylmethylhydroxyperidine succinate (EMHPS)/vitamin B

Influence of silicone mammoplasty on the immunoendocrine status of female recipients

The article concerns a study of early influence of silicone breast implants on the development of autoimmune reactions and dynamics of prolactin and thyroid hormone levels in women after mammoplasty. At the present time, this issue remains relevant for several reasons: more than 20 million pairs of implants have been installed in the world and the number of their implantations is constantly growing. Despite relative safety of the silicone implants, some of them are periodically banned by regulatory bodies in various countries. At the same time, there is a growing number of controversial publications in the scientific literature, about potential adverse consequences of their use. Some authors suggest an association between the silicone implants and risk of developing autoimmune conditions, connective tissue disorders, and occasional malignancies. On the other hand, the journals are full of publications about the overall safe tolerance of such medical devices by the patients. These considerations served as a pre-requisite to our research. As part of this project, we have assayed serum levels of autoantibodies to ten antigens, as well as contents of prolactin and thyroid hormones by means of ELISA technique in 27 patients before, 3 and 6 months after aesthetic and reconstructive mammoplastics performed within a period of September 2018 to November 2019. As a result, it was found that 5 out of 27 patients exhibited changes in the autoimmunity spectrum and intensity after mammoplasty. In particular, the concentrations of autoantibodies to modified citrullinated vimentin and IgM autoantibodies to cardiolipin exceeded the normal level at 3 and 6 months. In addition, the initially high prolactin concentration in mammoplasty recipients dropped to normal ranges by 3 months after breast surgery, even after several-fold increased initial levels. As for thyroid hormones, there were no statistically significant changes in their dynamics. The increase of autoantibodies to various target antigens after mammoplasty was statistically significant and positively correlated with each other. This can be explained, for example, by dependence on the adjuvant effect of silicone, which is not associated with antigen specificity. However, it may generally stimulate the immune responses

Mechanisms of the Vertical Secular Heating of a Stellar Disk

We investigate the nonlinear growth stages of bending instability in stellar disks with exponential radial density profiles.We found that the unstable modes are global (the wavelengths are larger than the disk scale lengths) and that the instability saturation level is much higher than that following from a linear criterion. The instability saturation time scales are of the order of one billion years or more. For this reason, the bending instability can play an important role in the secular heating of a stellar disk in the $z$ direction. In an extensive series of numerical $N$-body simulations with a high spatial resolution, we were able to scan in detail the space of key parameters (the initial disk thickness $z_0$, the Toomre parameter $Q$, and the ratio of dark halo mass to disk mass $M_{\rm h} / M_{\rm d}$). We revealed three distinct mechanisms of disk heating in the $z$ direction: bending instability of the entire disk, bending instability of the bar, and heating on vertical inhomogeneities in the distribution of stellar matter.Comment: 22 pages including 8 figures. To be published in Astronomy Letters (v.29, 2003

Bending Instability of Stellar Disks: The Stabilizing Effect of a Compact Bulge

The saturation conditions for bending modes in inhomogeneous thin stellar disks that follow from an analysis of the dispersion relation are compared with those derived from $N$-body simulations. In the central regions of inhomogeneous disks, the reserve of disk strength against the growth of bending instability is smaller than that for a homogeneous layer. The spheroidal component (a dark halo, a bulge) is shown to have a stabilizing effect. The latter turns out to depend not only on the total mass of the spherical component, but also on the degree of mass concentration toward the center. We conclude that the presence of a compact (not necessarily massive) bulge in spiral galaxies may prove to be enough to suppress the bending perturbations that increase the disk thickness. This conclusion is corroborated by our $N$-body simulations in which we simulated the evolution of almost equilibrium, but unstable finite-thickness disks in the presence of spheroidal components. The final disk thickness at the same total mass of the spherical component (dark halo + bulge) has been found to be much smaller than that in the simulations where a concentrated bulge is present.Comment: 27 pages including 10 figures. To be published in Astronomy Letters (v.31, No. 1, pp. 15-29 2005

Определение ионов меди(II) методом спектроскопии диффузного отражения

A method for copper(II) determination based on copper(II) ions interaction with the organic reagent picramine-ε, concentrating the formed complex on a solid-phase matrix and recording diffuse reflectance spectroscopy spectra by a portable combined LED miniphotometer was developed. Poly-ε-caproamide membranes were investigated as solid-phase matrixes. It was found that the diffuse reflectance coefficient of the studied membranes in the visible spectrum region does not depend on wavelength. So, the signal from membranes does not distort the results of the analysis. Factors controlling the process of sorption of the copper(II) complex with picramine-ε were studied. It was shown that the poly-ε-caproamide membranes are effective sorbents which provide the possibility of concentrating the analyte at a level higher than 105. The dependences of analytical signal on the acidity of the solution, the time of keeping the complex in the solution and the initial volume of the solution passed through the membrane were studied. Based on the obtained data, the optimal conditions of the analysis were found. Calibration dependence of the analytical signal on the concentration of copper(II) in model solutions was estimated. The method was tested for the determination of copper(II) ions in white wine. The method of additives was used for the analysis. It was found that the concentration of copper(II) ions in “Vagrus” wine is 0.0016 mkg/ml.Разработана методика определения меди(II), основанная на взаимодействии ионов меди(II) с органическим реагентом пикрамин-ε, концентрировании образовавшегося комплекса на твердой матрице и регистрации спектров диффузного отражения с помощью портативного комбинированного светодиодного минифотометра. В качестве твердых матриц исследованы поли-ε-капроамидные мембраны. Установлено, что коэффициент диффузного отражения таких мембран в видимой области практически не зависит от длины волны, поэтому сигнал от мембраны не влияет на результаты анализа. Изучены условия сорбции комплекса меди(II) с прикрамином-ε. Показано, что поли-ε-капроамидные мембраны являются эффективными сорбентами, которые обеспечивают возможность концентрирования аналита на уровне, превышающем 105. Исследованы зависимости кислотности среды, времени выдерживания комплекса в растворе, а также исходного объема раствора, пропускаемого через мембрану, на величину регистрируемого сигнала. Найдены оптимальные условия анализа. С использованием модельных растворов меди(II) построена градуировочная зависимость. Разработанная методика апробирована для определения ионов меди(II) в белом вине. Найдено, что в вине марки «Вагрус» (РФ) концентрация ионов меди(II) составляет 0.0016 мкг/см3. Анализ проведен с использованием метода добавок

Современные концепции молекулярного патогенеза рака щитовидной железы

Thyroid cancer remains the most common malignancy of the endocrine system worldwide. The indicators of its morbidity and mortality rates have been increasing rapidly over the last decades. Most cases of differentiated thyroid cancer (follicular and papillary histotypes) are clinically manifested by nodular goiter frequently combined with uncertain results of cytological diagnosis (categories III and IV according to the Bethesda (Bethesda System for Reporting Thyroid Cytopathology) classification). All of that makes it difficult to choose a proper tactic for patient treatment. It is known that the development, progression, invasion, and metastasis of cancer cells are regulated by a variety of molecular mechanisms. This review describes several molecular aspects of thyroid nodules oncogenesis, as well as its most promising diagnostic tumor markers. Following molecular pathways are described in particular: gene mutations, protein tumor markers, and epigenetic effects of micro-RNA, histones, as well as DNA methylation. The study of the pathogenesis of this disease has a prognostic value and contributes to the search for effective therapeutic and diagnostic methods and their improvement. That is why we also reviewed modern test panels aimed at preoperative differential diagnosis of thyroid nodules. Summarizing the results of world research on this topic allows us not only to expand the understanding of the fundamental processes of oncogenesis, but also to outline promising areas for future experimental research projects. All of that together will contribute to developing new prognostic, diagnostic and therapeutic technologies, and as a result, will improve the quality of medical care for patients with thyroid cancer.Рак щитовидной железы – распространенное злокачественное новообразование эндокринной системы. В последние десятилетия показатели заболеваемости и смертности вследствие этой патологии стремительно увеличиваются. Большинство случаев дифференцированного рака щитовидной железы (фолликулярного и папиллярного гистотипов) клинически проявляются как узловой зоб. Неопределенность результатов цитологической диагностики (категории III и IV по классификации Bethesda (Bethesda System for Reporting Thyroid Cytopathology)) обусловливает сложности в выборе тактики ведения пациентов. Известно, что развитие, прогрессирование, инвазия и метастазирование раковых клеток регулируются множеством молекулярных механизмов. В данной статье описываются некоторые молекулярные аспекты онкогенеза узловых образований щитовидной железы, а также наиболее перспективные диагностические онкомаркеры. В частности, рассматривается роль генных мутаций, белковых маркеров, эпигенетических воздействий микроРНК, гистонов и метилирования ДНК в патогенезе рака щитовидной железы. Изучение патогенеза этого заболевания имеет прогностическую ценность и способствует поиску эффективных лечебно-диагностических методов и их совершенствованию. Поэтому в исследовании были рассмотрены применяемые в настоящий момент тест-панели, направленные на дооперационную дифференциальную диагностику узловых образований щитовидной железы. Анализ и обобщение результатов исследований по данной теме позволят не только расширить понимание фундаментальных процессов онкогенеза, но и наметить перспективные направления планирования экспериментальных научных работ для разработки новых прогностических, диагностических и терапевтических технологий с целью повышения качества медицинской помощи пациентам с раком щитовидной железы

Determination of Copper(II) Ions by Diffuse Reflectance Spectroscopy Method

A method for copper(II) determination based on copper(II) ions interaction with the organic reagent picramine-ε, concentrating the formed complex on a solid-phase matrix and recording diffuse reflectance spectroscopy spectra by a portable combined LED miniphotometer was developed. Poly-ε-caproamide membranes were investigated as solid-phase matrixes. It was found that the diffuse reflectance coefficient of the studied membranes in the visible spectrum region does not depend on wavelength. So, the signal from membranes does not distort the results of the analysis. Factors controlling the process of sorption of the copper(II) complex with picramine-ε were studied. It was shown that the poly-ε-caproamide membranes are effective sorbents which provide the possibility of concentrating the analyte at a level higher than 105. The dependences of analytical signal on the acidity of the solution, the time of keeping the complex in the solution and the initial volume of the solution passed through the membrane were studied. Based on the obtained data, the optimal conditions of the analysis were found. Calibration dependence of the analytical signal on the concentration of copper(II) in model solutions was estimated. The method was tested for the determination of copper(II) ions in white wine. The method of additives was used for the analysis. It was found that the concentration of copper(II) ions in “Vagrus” wine is 0.0016 mkg/ml