ОПРЕДЕЛЕНИЕ МИНИМАЛЬНЫХ ИНГИБИРУЮЩИХ КОНЦЕНТРАЦИЙ БЕДАКВИЛИНА ДЛЯ ОЦЕНКИ ЛЕКАРСТВЕННОЙ ЧУВСТВИТЕЛЬНОСТИ МИКОБАКТЕРИЙ ТУБЕРКУЛЕЗА

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Хроническое ультрафиолетовое облучение индуцирует развитие устойчивой резистентности клеток меланомы к противоопухолевым препаратам

Introduction. Melanoma belongs to the group of the most malignant tumors characterized by aggressive growth and active metastasis. At the same time, the effectiveness of therapy, primarily targeted therapy, is largely limited by the rapid development of drug resistance.Aim. To study the effect of chronic ultraviolet (UV) irradiation on the formation of a population of radiation-resistant melanoma cells; to study the features of cell signaling and the sensitivity of UV-resistant melanoma cells to the antitumor drugs.Materials and methods. The experiments were carried out on in vitro cultured A375 melanoma cells. Cells were cultured in a standard DMEM + 10 % FBS medium; cell growth rate was analyzed using the MTT assay; cell survival after irradiation was analyzed using a colony-forming test. Determination of the transcriptional activity of the estrogen receptor (ER) was performed by reporter analysis upon transfection into cells of a plasmid containing the luciferase reporter gene controlled by estrogen responsive element. The immunoblotting method was used to analyze the expression of cellular proteins; comparative analysis of ERα and ERβ expression was performed by immunofluorescent method.Results. Long-term UV irradiation leads to the formation of a UV-resistant subpopulation of A375 melanoma cells, which is characterized by decreased sensitivity to targeted (vemurafenib) and hormonal (tamoxifen) drugs, increased expression of Snail, an activator of the epithelial-mesenchymal transition, and in the absence of noticeable changes in the expression of PI3K / mTOR signaling. Metformin reduces Snail expression in both parental and UV-resistant A375 cells and enhances the cytostatic effect in combination with vemurafenib or tamoxifen.Conclusion. The data obtained demonstrate a decrease in the sensitivity of melanoma cells to targeted drugs under the long-term exposure to UV. The ability of metformin to potentiate the action of targeted drugs and inhibit Snail allows us to consider metformin not only as an antitumor agent, but also as a potential inhibitor of the epithelial-mesenchymal transition.Введение. Меланома относится к группе наиболее злокачественных новообразований, отличающихся агрессивным ростом и активным метастазированием. при этом эффективность терапии, в первую очередь таргетной терапии, во многом ограничена быстрым развитием резистентности к препаратам.Цель исследования – изучить влияние хронического ультрафиолетового (УФ) облучения на формирование субпопуляции устойчивых к УФ клеток меланомы, а также особенности клеточного сигналинга и чувствительность УФрезистентных клеток меланомы к действию противоопухолевых препаратов.Материалы и методы. эксперименты проводились на культивируемых in vitro клетках меланомы А375. клетки культивировали в стандартной среде DMEM + 10 % FBS, анализ скорости роста клеток проводили с помощью МТТ-теста; выживаемость клеток после облучения анализировали с использованием колониеобразующего теста. Транскрипционную активность рецептора эстрогенов (ER) определяли методом репортерного анализа при трансфекции в клетки плазмиды, содержавшей ген-репортер люциферазы под контролем промотора с эстроген-респонсивным элементом. Для анализа экспрессии клеточных белков использовали метод иммуноблоттинга; сравнительный анализ экспрессии ERα и ERβ проводили с помощью иммунофлуоресцентного метода.Результаты. Длительное УФ-облучение приводит к формированию УФ-резистентной субпопуляции клеток меланомы А375, отличающейся пониженной чувствительностью к таргетным (вемурафенибу) и гормональным (тамоксифену) препаратам на фоне повышенной экспрессии Snail – активатора эпителиально-мезенхимального перехода и при отсутствии заметных изменений в экспрессии белков PI3K (фосфоинозитид-3-киназы) / mTOR (мишень рапамицина млекопитающих) сигналинга. Метформин снижает экспрессию Snail как в родительских, так и в УФ-резистентных клетках А375 и усиливает цитостатический эффект в комбинации с вемурафенибом или тамоксифеном.Заключение. полученные данные свидетельствуют о снижении чувствительности к таргетным препаратам клеток меланомы на фоне длительной экспозиции с УФ. Способность метформина потенцировать действие таргетных препаратов и ингибировать Snail позволяет рассматривать это лекарственное стредство не только как противоопухолевый агент, но и как потенциальный ингибитор эпителиально-мезенхимального перехода

Magnetic Iron Oxide Nanoparticles: Synthesis and Surface Functionalization Strategies

Surface functionalized magnetic iron oxide nanoparticles (NPs) are a kind of novel functional materials, which have been widely used in the biotechnology and catalysis. This review focuses on the recent development and various strategies in preparation, structure, and magnetic properties of naked and surface functionalized iron oxide NPs and their corresponding application briefly. In order to implement the practical application, the particles must have combined properties of high magnetic saturation, stability, biocompatibility, and interactive functions at the surface. Moreover, the surface of iron oxide NPs could be modified by organic materials or inorganic materials, such as polymers, biomolecules, silica, metals, etc. The problems and major challenges, along with the directions for the synthesis and surface functionalization of iron oxide NPs, are considered. Finally, some future trends and prospective in these research areas are also discussed

Gene mutation and drug resistance of <i>M. tuberculosis</i> in the patients followed up in the city of Moscow

The article describes a retrospective study of the results of microbiological and molecular genetic tests of 685 M. tuberculosis cultures isolated from 685 adult tuberculosis patients registered for dispensary follow-up in Moscow in 2014.The following was identified during the study: phenotypic drug resistance (FDR) of MTB to rifampicin, isoniazid, fluoroquinolones, kanamycin, amikacin, and capreomycin in groups of patients with different treatment history; the frequency of FDR to the above anti-tuberculosis drugs in strains with mutations being drug resistance markers; the frequency of various mutations in case of FDR of mycobacteria in the patients from different groups; the relationship of FDR or the presence of a particular mutation with various characteristics of the patients and their treatment history.The history of previous treatment was determined as statistical significance to provide the greatest influence on the spread of drug resistant MTB: patients undergoing repeated treatment had FDR more often and also a much more pronounced variety of mutations being markers of FDR to certain anti-tuberculosis drugs.The results of the study showed that the detection of genetic mutations in MBT associated with FDR was a reliable tool for predicting phenotypic resistance and should be used as the main method for selecting anti-tuberculosis drugs when compiling the etiotropic therapy regimen

Features of the Biotopic Distribution of Different Species of Small Mammals and their Role in Supporting the Natural Foci of Tularemia in the North-Eastern Part of the Voronezh Region

Different species of small mammals (SM) (539 total), cached in Voronezh region, were examined for antigen and DNA of Francisella tularensis. The basic species of SM involved in circulation of F. tularensis were revealed. The features of the biotopic distribution of infected SM on the territory of the natural foci were shown. The diversity of species SM ensures long operation and epizootic activity of the natural foci of tularemia

Enzyme Replacement Therapy and Hematopoietic Stem Cell Transplantation Results in Patients with Hurler Syndrome: Clinical Cases

Mucopolysaccharidosis type I (MPS I) is the hereditary disease characterized with alpha-L-iduronidase activity decrease and further accumulation of heparan and dermatan sulfate in lysosomes. MPS I is rare autosomal recessive disorder with incidence of 0.5–4 cases on 100.000 live-birth infants. Meantime there two approaches in MPS I treatment: hematopoietic stem cell transplantation (HSCT) and enzyme replacement therapy (ERT). HSCT can be the best option for treatment of patients with severe MPS I (Hurler syndrome). Successful engraftment moderates such clinical signs as obstructive airway diseases, hepatosplenomegaly, cardiovascular system dysfunctions. HSCT prevents cognitive functions decline and other pathologic features of central nervous system. Presented clinical cases show various clinical courses according to age of diagnosis, ERT onset and HSCT implementation

Diagnostic Difficulties of Mucopolysaccharidosis Type I Mild Forms: Clinical Cases

Mucopolysaccharidosis type I mild forms include Scheie syndrome and Hurler-Scheie syndrome that are characterized by slow progression, intact intelligence, and primarily effect on visual organ, musculoskeletal and cardiovascular systems. Early diagnostics, multidisciplinary approach to examination and monitoring, timely management are crucial in maintenance of patients' quality of life, preventing complications development and early disability. The article provides the overview of published data and description of 3 clinical cases with mild course of mucopolysaccharidosis type I

EXPERIENCE IN APPLYING EDUCATIONAL PROGRAM FOR PEDIATRICIANS ON EMERGENCY CARE FOR CHILDREN USING MOBILE SIMULATION EQUIPMENT

The article describes the experience of implementing the “Emergency pediatrics” educational program with the use of simulation training methods, mobile simulation equipment, and distance educational technologies. The program is aimed at improving the doctors’ professional competence in emergency medical care for children. This format of the training helps to train the largest number of doctors in accordance with the international standards for emergency medical care on-the-job. The educational program makes it possible to assess the level of initial and final knowledge, to monitor professional skills, to determine the degree of the doctor’s readiness for emergency medical care for children. Based on the results of the incoming test control and assessment of basic cardiopulmonary resuscitation skills, we can conclude that the pediatricians have insufficient theoretical and practical skills of emergency care. As a promising direction, we plan to create a Register for sudden cardiac arrest, the Register of survival after sudden cardiac arrest in children at hospital and outside the hospital, which improve the quality of emergency and urgent care for children