Technology of manufacturing the reliable silicon photoconverters with long operation time

We offer to use an amorphous metal alloy Al₈₀Ni₂₀ as ohmic contact and current-collecting tracks to silicon photoconverters (PC) based on p-n junctions. Technological processes for production of silicon photosensitive structures and film coatings with an amorphous structure are described. The data of the X-ray structure analysis of the metal alloy Al₈₀Ni₂₀ confirming amorphism were obtained. The key PC parameters are determined

Physiological features of cells and microvasculature under the local hypothermia influence

Hypothermia or cold therapy is the local or systemic application of cold for therapeutic purposes. Local application of cold is used to control inflammation: pain and swelling, hematoma and trismus reduction. Despite the frequent use of cooling in prosthodontic rehabilitation and in physical therapy, as evidenced by many reports in the literature, there is scientific documentation that suggests disadvantages of using this treatment in maxillofacial surgery and oral surgery. Also the clinical studies that have been carried out in maxillofacial surgery and oral surgery have been conducted in an empirical manner, which casts doubt on the results. In view of this, it is relevant to study the mechanisms of microcirculatory preconditioning and hypothermia. This physiological process is so interesting for the development of medical devices of controlled hardware hypothermia to prevent inflammatory symptoms at the stage of rehabilitation by targeting the vascular and cellular component of the inflammatory process in different areas of the human body. To date, the use of local hardware controlled hypothermia in various pathological conditions in humans is a topical trend in medicine. Microcirculatory bloodstream is directly related to temperature factors. Although there are concepts of vascular spasm or dilatation in the microcirculatory bloodstream during systemic hypothermia, there are no reliable data on the cellular and vascular reactions during local hypothermia. In this paper, a search for fundamental and current scientific work on the topic of cellular and vascular changes under the influence of hypothermia was conducted. The search for data revealed that the mechanisms of intracellular hypothermia are of particular interest for the development of therapeutic treatments after surgical interventions in areas with extensive blood supply. With this in mind, it is relevant to investigate several areas: the role of endothelium, glycocalyx and blood cells in microcirculatory-mediated preconditioning and intracellular hypothermia, and in the molecular mechanism that regulates these processes, whether they occur in the same way in all tissues.Гипотермия или терапия холодом является местным или системным применением холода в терапевтических целях. Местное применение холода используется для контроля воспалительного процесса: боли и отека, гематомы, снизить тризм. Несмотря на частое использование охлаждения в ортопедической реабилитации и физиотерапии, о чем свидетельствует множество сообщений в литературе, существуют научные данные, которые говорят о недостатках применения в челюстно-лицевой хирургии и хирургической стоматологии. Также клинические исследования, которые проводились на базе челюстно-лицевой хирургии и хирургической стоматологии, проводились эмпирическим путем, что ставит под сомнения результаты исследования. Ввиду этого актуально изучение механизмов микроциркуляторного прекондиционирования и гипотермии. Данный физиологический процесс представляет особый интерес для разработки медицинских устройств контроллируемой аппаратной гипотермии для предотвращения воспалительных симптомов на этапе реабилитации, целенаправленно воздействуя на сосудисто-клеточный компонент воспалительного процесса в разных областях тела человека. На сегодняшний день применение локальной аппаратной контролируемой гипотермии при различных патологических состояниях человека актуальное направление в медицине. Микроциркуляторное русло напрямую связано с температурными факторами. Несмотря на то, что существуют понятия сосудистых спазма или дилятации в микроциркуляторном русле при системной гипотермии, отсутствуют достоверные данные по клеточно-сосудистым реакциям при локальной гипотермии. В данной работе проведен поиск фундаментальных и современных научных работ на тему клеточно-сосудистых изменений под влиянием гипотермии. При поиске данных было выявлено, что механизмы внутриклеточной гипотермии представляет особый интерес для разработки терапевтических методов лечения после оперативных вмешательств в областях с обильным кровоснабжением. Исходя из этого актуально проведение исследований, направленных на изучение нескольких направлений: роль эндотелия, гликокаликса и клеток крови в микроциркуляторно-опосредованном прекондиционирования и внутриклеточной гипотермии, а также при молекулярном механизме, регулирующем эти явления, одинаково ли они проходят во всех тканях

Vitamin D effects on guided bone regeneration and osseointegration of dental implants (literature review) [Влияние витамина D на регенерацию костной ткани при реконструктивных операциях в полости рта и остеоинтеграцию дентальных имплантатов (обзор литературы)]

Background. Due to the prevalence of Vitamin D deficiency as well as the frequency of reconstructive surgical interventions followed by dental implantation, the issue arises concerning the effect of Vitamin D on reparative regeneration of bone and osseointegration of dental implants. The purpose - using literature data we are conducting an impact assessment of vitamin D on reparative regeneration of bone tissue, in particular, after oral reconstruction surgeries and dental implantation. Methods. Retrieval, systematization and analysis of scientific data on application of vitamin D supplementation and its effect on reparative regeneration of jaw bone tissue. The conclusions. For the most part, the positive effect exerted on reparative regeneration of jaw bone tissue and osseointegration of dental implants is due to the role of vitamin D in physiological processes evolving in bone tissue, namely maintenance of calcium and phosphate exchange through intestinal absorption and TNFα, RANKL (Receptor activator of nuclear factor kappa-B ligand) and consequently differentiation of precursors to osteoclasts into osteoclasts through VDR stimulation (Vitamin D Receptor) - receptors for further osteogenesis. Also, according to literature data, FGF23 (Fibroblast Growth Factor) protein is a marker of osteoblasts differentiation into osteocytes, it is also known that FGF23 and 1,25(ОН)2D3 are genetically related. FGF23 is the main regulator of both phosphate exchange in bones and metabolism of vitamin D and its metabolites. Besides, indirect anti-inflammatory effect has been observed thanks to inhibition of pro-inflammatory cytokine secretion. Taking into account the abovementioned data, of particular relevance is the definition of serum concentration 25(ОН)D and development of schemes of vitamin D level pre-surgery correction in patients, who have to undergo oral reconstruction surgeries and dental implantation. Mass spectrometry is a promising diagnostic method for determining the level of vitamin D in a body, as it allows to identify the actual amount of vitamin D free from admixture of other steroid hormones. The introduction of this method into clinical practice will allow to monitor the level of vitamin D in patients, receiving reconstructive and rehabilitative treatment. © 2020 Izdatel'stvo Meditsina. All rights reserved

Developing Techniques of Acoustic Microscopy for Monitoring Processes of Osteogenesis in Regenerative Medicine

Abstract: High-resolution ultrasonic imaging techniques are necessary for the non-invasive diagnostics of artificial cell-matrix systems. The results from experimental studies show these techniques are sensitive to variations in the elastic properties of biopolymer samples and can be used effectively to detect micro and macro voids and monitor processes of biodegradation in tissue-engineered constructs (TECs). © 2020, Allerton Press, Inc

Biocompatibility and Bioresorption of 3D-Printed Polylactide and Polyglycolide Tissue Membranes

We studied biocompatibility and bioresorption of 3D-printed polylactide and polyglycolide tissue membranes. Ultrasound microscopy and histological examination showed that membranes fabricated of a copolymer of lactic and glycolic acids in a mass ratio of 1:9 are bioresorbed and have good biocompatibility with soft tissues (connective tissue, adipose tissue, and epithelium). An important feature of the copolymer membranes, which differs them from pure polylactide membranes, is the formation of a thin fibrous capsule that did not interfere its destruction by the mechanism of hydrolytic resorption. © 2021, Springer Science+Business Media, LLC, part of Springer Nature