Factors of colonization resistance of oral mucous membranes in individuals using dental orthopedic constructions: peculiarities of biofilm-forming activity of microorganisms

The article presents the results of assessing the biofilm-forming ability of the oral microflora in individuals using dental orthopedic constructions. It has been established that microorganisms isolated from oral fluid of persons using removable dentures and implants have a pronounced ability to form biofilms, in comparison with the microflora of persons without dental orthopedic constructions (p<0,05).В статье представлены результаты оценки биопленкообразующей способности микрофлоры ротовой полости у лиц, использующих стоматологические ортопедические конструкции. Установлено, что микроорганизмы, выделенные из ротовой жидкости лиц, использующих съемные зубные протезы и имплантаты, обладают выраженной способностью к образованию биопленок, в сравнении с микрофлорой лиц без стоматологических ортопедических конструкций (р<0,05)

Вакцинация против новой коронавирусной инфекции пациентов с отягощенным сердечно-сосудистым и аутоиммунным анамнезом

The review article is devoted to a discussion of the issues of vaccination against a new coronavirus infection in patients with cardiovascular and autoimmune diseases. Presented at the time of this writing are data on domestic vaccines safety in the Russian Federation: combined vector vaccines “Gam-COVID-Vac” and “Gam-COVID-Vac-Lyo”, peptide-based vaccine “EpiVacCorona”, concentrated, purified and inactivated whole-virion “KoviVac” vaccine, and a standalone vaccine/booster shot “Sputnik Light”. The analysis of the main contraindication applicable to the vaccines in different categories of patients has been carried out. A number of consensus documents published by Russian and foreign professional medical associations and communities on the issues of vaccination of patients with cardiovascular and autoimmune diseases are considered in detail.Обзорная статья посвящена обсуждению вопросов вакцинопрофилактики новой коронавирусной инфекции (COVID-19) у пациентов с сердечно-сосудистыми и аутоиммунными заболеваниями. Представлены актуальные на момент написания статьи данные по вопросам безопасности зарегистрированных в Российской Федерации отечественных вакцин: комбинированных векторных вакцин «Гам-КОВИД-Вак» и «Гам-КОВИД-Вак-Лио», вакцины на основе пептидных антигенов «ЭпиВакКорона», вакцины коронавирусной инактивированной цельновирионной концентрированной очищенной «КовиВак» и вакцины для профилактики COVID-19 «Спутник Лайт». Проведен анализ основных ограничений к вакцинации данными препаратами у различных категорий больных. Подробно рассмотрен ряд консенсусных документов, опубликованных российскими и зарубежными профессиональными медицинскими ассоциациями и сообществами, по вопросам вакцинации пациентов с сердечно-сосудистыми и аутоиммунными заболеваниями

Loss of C2orf69 defines a fatal autoinflammatory syndrome in humans and zebrafish that evokes a glycogen-storage-associated mitochondriopathy

Summary Human C2orf69 is an evolutionarily conserved gene whose function is unknown. Here, we report eight unrelated families from which 20 children presented with a fatal syndrome consisting of severe autoinflammation and progredient leukoencephalopathy with recurrent seizures; 12 of these subjects, whose DNA was available, segregated homozygous loss-of-function C2orf69 variants. C2ORF69 bears homology to esterase enzymes, and orthologs can be found in most eukaryotic genomes, including that of unicellular phytoplankton. We found that endogenous C2ORF69 (1) is loosely bound to mitochondria, (2) affects mitochondrial membrane potential and oxidative respiration in cultured neurons, and (3) controls the levels of the glycogen branching enzyme 1 (GBE1) consistent with a glycogen-storage-associated mitochondriopathy. We show that CRISPR-Cas9-mediated inactivation of zebrafish C2orf69 results in lethality by 8 months of age due to spontaneous epileptic seizures, which is preceded by persistent brain inflammation. Collectively, our results delineate an autoinflammatory Mendelian disorder of C2orf69 deficiency that disrupts the development/homeostasis of the immune and central nervous systems

Induction of Membrane Ceramides: A Novel Strategy to Interfere with T Lymphocyte Cytoskeletal Reorganisation in Viral Immunosuppression

Silencing of T cell activation and function is a highly efficient strategy of immunosuppression induced by pathogens. By promoting formation of membrane microdomains essential for clustering of receptors and signalling platforms in the plasma membrane, ceramides accumulating as a result of membrane sphingomyelin breakdown are not only essential for assembly of signalling complexes and pathogen entry, but also act as signalling modulators, e. g. by regulating relay of phosphatidyl-inositol-3-kinase (PI3K) signalling. Their role in T lymphocyte functions has not been addressed as yet. We now show that measles virus (MV), which interacts with the surface of T cells and thereby efficiently interferes with stimulated dynamic reorganisation of their actin cytoskeleton, causes ceramide accumulation in human T cells in a neutral (NSM) and acid (ASM) sphingomyelinase–dependent manner. Ceramides induced by MV, but also bacterial sphingomyelinase, efficiently interfered with formation of membrane protrusions and T cell spreading and front/rear polarisation in response to β1 integrin ligation or αCD3/CD28 activation, and this was rescued upon pharmacological or genetic ablation of ASM/NSM activity. Moreover, membrane ceramide accumulation downmodulated chemokine-induced T cell motility on fibronectin. Altogether, these findings highlight an as yet unrecognised concept of pathogens able to cause membrane ceramide accumulation to target essential processes in T cell activation and function by preventing stimulated actin cytoskeletal dynamics

СРАВНЕНИЕ МОРФОЛОГИЧЕСКИХ И ХИМИЧЕСКИХ СВОЙСТВ СФЕРИЧЕСКИХ И ИГОЛЬЧАТЫХ КАЛЬЦИЙ-ФОСФАТНЫХ БИОНОВ

Aim. To compare morphological properties, mineral, and organic profile of spherical calcium phosphate bions (SCPB) and needle calcium phosphate bions (NCPB) for the assessment of the CPB-specific endothelial toxicity in models of mild or severe hypercalcemia/hyperphosphatemia in the further studies.Methods. Both SCPB and NCPB were artificially synthesized employing blood-mimetic medium either moderately or significantly supersaturated of calcium and phosphorus salts. Size and shape of SCPB and NCPB were investigated by scanning and transmission electron microscopy and atomic force microscopy. Elemental analysis was performed utilizing energy-dispersive X-ray spectroscopy, atomic emission spectroscopy, and CHNSO analysis, functional groups were examined using Fourier-transform infrared spectroscopy and Raman spectroscopy while chemical formula was identified by X-ray powder diffraction analysis. Protein profile of SCPB and NCPB was screened employing sodium dodecyl sulfate polyacrylamide gel electrophoresis following silver staining.Results. SCPB were visualized as crystalline spherical spongeous particles of 80-200 nm diameter and mean diameter of around 120 nm while NCPB represented needle crystals of a similar diameter. Both SCPB and NCPB had similar crystallinity, surface charge and tended to form clusters of several particles. Furthermore, both SCPB and NCPB were composed of carbon, oxygen, hydrogen, nitrogen, calcium, and phosphorus, contained phosphate (PO4 3-), carbonate (CO3 2-), and hydroxyl (OH- ) functional groups, and consisted of hydroxyapatite (Ca10(PO4 )6 (OH)2 ) and carbonate-hydroxyapatite (Ca10(PO4)3 (CO3)3 (OH)2 ). In addition, protein profile of SCPB and NCPB was similar and notable for the abundant albumin and fetuin A levels.Conclusion. Having similar size, surface charge, extent of crystallinity, and chemical composition, SCPB and NCPB possess a different shape. Цель Сравнить морфологию, минеральный и органический профиль сферических кальций-фосфатных бионов (СКФБ) и игольчатых кальций-фосфатных бионов (ИКФБ), необходимых для оценки эндотелиотоксического действия КФБ при моделировании умеренной и тяжелой гиперкальциемии/гиперфосфатемии в последующих исследованиях. Материалы и методы СКФБ и ИКФБ были искусственно синтезированы посредством умеренного и выраженного перенасыщения имитирующей состав крови среды солями кальция и фосфора. Размерность и форма СКФБ и ИКФБ были изучены при помощи сканирующей и просвечивающей электронной микроскопии и атомно-силовой микроскопии. Элементный анализ проводился посредством энергодисперсионной рентгеновской спектроскопии, атомно-эмиссионной спектроскопии и CHNSO-анализа, функциональные группы идентифицировались при помощи инфракрасной спектроскопии с преобразованием Фурье и спектроскопии комбинационного рассеяния света, формула входящих в состав бионов химических соединений и степень их кристалличности определялась методом рентгеновской порошковой дифрактометрии. Белковый профиль СКФБ и ИКФБ был исследован путем электрофореза в полиакриламидном геле в присутствии додецилсульфата натрия с последующим окрашиванием нитратом серебра. Результаты СКФБ визуализировались как кристаллические сферические частицы губчатой структуры диаметром 80–200 нм и средним диаметром около 120 нм, в то время как ИКФБ представляли собой игольчатые кристаллы такого же диаметра. Как СКФБ, так и ИКФБ имели схожий поверхностный заряд и были склонны к агрегации. СКФБ и ИКФБ состояли из углерода, кислорода, водорода, азота, кальция и фосфора, содержали фосфатные (PO4 3-), карбонатные (CO3 2-) и гидроксильные (OH- ) группы и состояли из гидроксиапатита (Ca10(PO4 ) 6 (OH)2 ) и карбонат-гидроксиапатита (Ca10(PO4 ) 3 (CO3 ) 3 (OH)2 ). Кроме того, СКФБ и ИКФБ обладали идентичной степенью кристалличности и схожим белковым профилем с преобладанием альбумина и фетуина-А над остальными белками. Заключение СКФБ и ИКФБ отличаются лишь формой, имея схожие размерность, поверхностный заряд, степень кристалличности и химический соста

СРАВНИТЕЛЬНОЕ ТЕСТИРОВАНИЕ IN VITRO БИОДЕГРАДИРУЕМЫХ СОСУДИСТЫХ ИМПЛАНТОВ ДЛЯ ОЦЕНКИ ПЕРСПЕКТИВЫ ИСПОЛЬЗОВАНИЯ В ТКАНЕВОЙ ИНЖЕНЕРИИ

We prepared polycaprolactone (PCL) and polyhydroxybutyrate/valerate (PHBV)/polycaprolactone (PCL) 2 mm vascular grafts using electrospinning. The structure of the graft surface along with the physico-mechanical and viscoelastic properties were investigated by scanning electron microscopy, universal testing machine (n=20), and arterial pulsatile flow circuit (n=12), respectively. We also assessed hemocompatibility and thromboresistance of the inner graft surface (n=12). Cell adhesion and viability were investigated using EA.hy 926, an endothelial cell line that was cultured on the cultural plate, PCL, and PHBV/PCL scaffolds during 6 days.PCL and PHBV/PCL grafts consisted of ≤ 4 μm diameter fibers which were randomly distributed and formed ≤ 40 μm diameter pores. The durability, elasticity, and stiffness of PCL grafts were 2,7-fold lower, 10,7-fold higher, and 2,9-fold higher, respectively, compared to autologous saphenous veins (р&lt;0,001). However, the durability, elasticity, and stiffness of PHBV/PCL grafts were 1,9-fold higher, 1,8-fold lower, and 6,9-fold higher in comparison with PCL grafts (р&lt;0,001). Viscoelastic properties of both PCL and PHBV/PCL grafts differed from native arteries (p&lt;0,001) but were more similar to them then Dacron and ePTFE grafts. After the contact with blood, inner surface of PHBV/PCL grafts contained minimal amount of proteins and blood cells, and there were no signs of platelet activation. However, PCL grafts contained a high amount of proteins and induced platelet activation. After 6 days of culture, the number of EA.hy 926 cells was lower on PCL scaffolds compared to the PHBV/PCL scaffolds and cultural plate; the viability of the cells was similar.На основе поликапролактона (ПКЛ) и композиции полигидроксибутирата/валерата и поликапролактона (ПГБВ/ПКЛ) методом электроспиннинга изготовлены сосудистые графты диаметром 2 мм. Структура поверхности графтов изучена методом сканирующей электронной микроскопии, физико-механические свойства – на разрывной машине (n=20), вязкоэластические свойства – на установке артериального пульсирующего потока (n=12). Оценена гемосовместимость и тромборезистентность внутренней поверхности графтов (n=12). С использованием культуры эндотелиальных клеток линии Ea.hy 926 изучены адгезивные характеристики и жизнеспособность клеток, культивируемых на полимерных матриксах в течение 6 суток.Разработанные ПКЛ- и ПГБВ/ПКЛ-графты состояли из полимерных нитей диаметром до 4 мкм, которые при своем хаотичном расположении формировали поры размером до 40 мкм. ПКЛ-графты были в 2,7 раза менее прочными, но в 10,7 раза более эластичными, чем аутовены (p&lt;0,001). Жесткость ПКЛ-графтов 2,9 раза превысила жесткость аутовен (р&lt;0,001). Добавление в полимерный состав графтов ПГБВ способствовало повышению прочности материала в 1,9 раза и снижению его относительного удлинения в 1,8 раза (р&lt;0,001). Жесткость материала при этом возросла в 6,9 раза (р&lt;0,001). Вязкоэластические свойства полимерных графтов статистически значимо отличались от вязкоэластических свойств артерий (p&lt;0,001), однако были с ними более схожи, чем с аналогичными свойствами сосудистых имплантов из Dacron и ePTFE. После контакта с кровью на внутренней поверхности ПГБВ/ПКЛ-матриксов обнаружили минимальное количество протеинов и форменных элементов крови, активации тромбоцитов не происходило. На поверхности ПКЛ-матриксов отмечена активация тромбоцитов и большее количество белка. После культивиро- вания клеток линии Ea.hy 926 на поверхности ПКЛ-матриксов абсолютное количество клеток оказалось в 1,5 раза меньше, чем на культуральном пластике. Введение в состав полимерной композиции ПГБВ привело к увеличению количества адгезированных клеток, которые располагались как на поверхности, так и внутри матриксов. Достоверного снижения клеточной жизнеспособности при культивировании на полимерных матриксах не отмечено

THE SPECTRUM OF BACTERIAL AGENTS ISOLATED FROM THE WOUND IN PATIENTS WITH DIABETIC FOOT SYNDROME IN ONE OF THE HOSPITALS IN CHELYABINSK

Aim. To establish the features of the spectrum and antibiotic resistance of bacterial agents isolated from wounds in patients with diabetic foot syndrome.Materials and methods. In 2016-2017 a retrospective cohort study was carried out on the basis of the archive of the municipal budgetary healthcare institution «City clinical hospital №6» in Chelyabinsk with analyzing the data of the medical cards of patients who were at the department of purulent surgery in 2015 with various forms of diabetic foot syndrome. The main data for the study were taken from the results of bacteriological studies. To determine the antibiotic susceptibility of the isolated flora, a diffusion method was used with discs with antibiotics. The classification proposed by Wagner F.W. was used to determine the prevalence and depth of the lesion of diabetic foot syndrome (1979). The statistical processing of data was carried out using Excel 12.0 (Office 2008), the level of significance of the results was evaluated by calculating the two-sided exact Fisher test (F) using the calculator on the site «Medical Statistics» (URL: http://medstatistic.ru/calculators/calchi.html).Results. In the studied group of patients with diabetic foot syndrome the infectious process caused by one bacterial agent was most often encountered. The most common causative agent isolated from the wound defects was S. aureus. The tendency to develop resistance against antibiotics, widely used in clinical practice, is more pronounced in representatives of gram-negative flora.Conclusion. The obtained data generally coincide with the results of studies in the field of the microbial spectrum of the wounds in diabetic foot syndrome determined by other authors, but the predominance of monoinfections over bacterial associations in this studied population requires further study

Modern Conceptions about the Mechanisms of Interaction Between Biofilm and Cellular Immunity Factors

Features of the cellular immune response in the presence of a microbial biofilm are well described in the literature. Based on numerous studies, it became possible to establish a number of patterns: mature biofilms are better protected from immune factors, the effectiveness of antibiofilm strategies depends on species of the microorganisms, forming the biofilm, and, accordingly, on the composition of the biopolymer matrix. For example, rhamnolipids and alginate of Pseudomonas aeruginosa exert a significant negative effect on the function of immunocompetent cells. The bacteria of biofilms became able to turn to their advantage many of the protective reactions developed by the immune system and fixed evolutionarily, applying them for the growth and development of the microbial consortium

MICROFLORA OF THE ORAL CAVITY AND CONDITION OF ANTI-INFECTION PROTECTION FACTORS IN PERSONS USING DENTAL ORTHOPEDIC CONSTRUCTIONS (DOC)

Aim. To study the qualitative composition, the quantitative content of microorganisms, to assess the viability and functional status of neutrophils in the oral fluid of patients using removable and non-removable DOC. Materials and methods. The present study used a free oral fluid of 100 patients aged 21 to 79 years. The qualitative and quantitative composition of the microflora was determined using the PCR method by means of the Femoflor-16 system (NPO DNA-technology, Russia). Determination of the total number of leukocytes was carried out in Goryaev's chamber, analysis of their viability was carried out with Trypan blue staining. Acridine orange was used to study the indices of lysosomal activity of neutrophils. Oxygendependent metabolism was studied using the Nitro Blue-Tetrazolium (NBT) test, and the phagocytic function was determined by the absorption of latex particles. Results. In persons using dentures, the qualitative and quantitative composition of the microflora of the oral cavity changes. The method of hygienic care of the DOC significantly does not affect the composition of the microflora of the oral fluid of patients. In persons using DOC, a decrease in the total number of leukocytes and their viable forms in the free oral fluid was established. However we registered the stability of functioning of viable neutrophils in patients with removable DOC and a significant decrease in the phagocytic ability and microbicidal oxygen-dependent potential of neutrophils when using non-removable DOC. Conclusion. Foreign body in the form of a removable or non-removable DOC changes the functioning of the factors of congenital anti-infective protection of the oral mucosa, which can lead to the development of infectious complications during dental prosthetics