Effectiveness of Autologous Platelet-Rich Plasma and Stromal Vascular Fraction in Autologous Skin Grafting

Introduction: Despite the medical advances, burns remain a serious challenge and require new and promising treatment options, such as biomedical technologies with a high potential for burn wound treatment. However, high cost and complexity of biotechnologies limit their routine use, but autologous tissues, such as stromal vascular fraction (SVF) and autologous platelet-rich plasma (PRP), overcome these shortcomings.   Objective: To demonstrate a successful case of using a combination of adipose-derived SVF and autologous PRP during autologous skin grafting in a severely burned patient.   Material and methods: We present a successful case of 84-year-old Patient B. treated at Saint Petersburg I. I. Dzhanelidze Research Institute of Emergency Medicine in September-October 2022. He was diagnosed with a 11% (6%) / II-III degree flame burn of the head, neck, trunk, and upper extremities and first-degree inhalation injury. At the first stage, the general condition of the patient was stabilized, and he was prepared for surgery. At the second stage, on day 25 of treatment we performed skin grafting using split-thickness autografts with rare perforations and application of SVF and autologous PRP on a burn wound. We evaluated the treatment effectiveness using planimetry, cytology, and histology.   Results: We observed complete engraftment of the autograft with no lysis or rejection during the first dressing change on day 3 after surgery and complete skin restoration on day 11. Cytologic findings over time showed an active decrease in inflammatory cells and an increase in regenerative cells, indicating successful wound healing. Histology demonstrated formation of normal stratified squamous epithelium with areas of hyperkeratosis and young granulation tissue in the superficial layers of the dermis on day 6.   Conclusions: Our case demonstrated that the combination of SVF and autologous PRP facilitates split-thickness skin autograft engraftment

Evaluating the effectiveness of combined use of non-thermal atmospheric pressure plasma and frequently-modulated electric field signal in skin wound healing

Background. Scientists around the world are interested in applying physical phenomena to various fields of science. The development of entire areas united by one concept (‘plasma medicine’, etc.) stands as an outstanding example. This study focuses on only two concepts of interest, which are plasma jet and electric field, as far as results of their combined use in clinical practice and in surgery remain understudied. Objective. Experimental evaluation of the effectiveness of physical methods of treatment in skin wound healing. Material and Methods. Animal testing involved 45 small laboratory animals (rats). They were divided into 5 groups of 9 according to methods for experimental wound healing. To generate the plasma jet, a portable generator was used, which is the original development of specialists of the Peter the Great St. Petersburg Polytechnic University. Planimetric and histological measurements were analysed. The antibacterial effectiveness of methods under research was investigated using Staphylococcus aureus 209P, cultivated in vitro on 6- and 12-millimeter discs. Discussion. A combination of non-thermal atmospheric pressure plasma and frequency-modulated electric field signal exhibited the ability to accelerate eschar separation by 52.1% (p < 0.05) and stimulate restorative regeneration by 56% (p < 0.05). Combination of physical methods of treatment demonstrated pronounced antibacterial effect. A histological examination on biopsy sample on the 21st day of observation revealed formed (mature) granulations and large number of newly formed vessels. The cellular composition of epidermal basement membrane showed high level of differentiation. Conclusion. The data obtained suggest that the use of the proposed methods in clinical practice will improve the treatment process of the patients with wounds of different etiology

Power supplies for dual-frequency induction melting of metals

The article discusses the benefits of multi frequency induction melting in the production of synthetic cast iron, structural (electric circuit) principles of dual frequency Power supplies of melting systems. The ways of electric power regulation of low frequency and high frequency components of the current in the inductor sections of furnace are demonstrated, namely power rescheduling at the metal melting stage, alloying stage and recarburizing of synthetic cast iron

Raman Scattering:From Structural Biology to Medical Applications

This is a review of relevant Raman spectroscopy (RS) techniques and their use in structural biology, biophysics, cells, and tissues imaging towards development of various medical diagnostic tools, drug design, and other medical applications. Classical and contemporary structural studies of different water-soluble and membrane proteins, DNA, RNA, and their interactions and behavior in different systems were analyzed in terms of applicability of RS techniques and their complementarity to other corresponding methods. We show that RS is a powerful method that links the fundamental structural biology and its medical applications in cancer, cardiovascular, neurodegenerative, atherosclerotic, and other diseases. In particular, the key roles of RS in modern technologies of structure-based drug design are the detection and imaging of membrane protein microcrystals with the help of coherent anti-Stokes Raman scattering (CARS), which would help to further the development of protein structural crystallography and would result in a number of novel high-resolution structures of membrane proteins—drug targets; and, structural studies of photoactive membrane proteins (rhodopsins, photoreceptors, etc.) for the development of new optogenetic tools. Physical background and biomedical applications of spontaneous, stimulated, resonant, and surface- and tip-enhanced RS are also discussed. All of these techniques have been extensively developed during recent several decades. A number of interesting applications of CARS, resonant, and surface-enhanced Raman spectroscopy methods are also discussed

Terahertz Crystal

FIELD: chemistry. SUBSTANCE: invention relates to terahertz (THz) materials, namely to crystals in demand for use in medicine, pharmaceuticals, customs remote control and other areas. The terahertz crystal according to the invention is characterized by being made on the basis of single-phase solid solutions of the AgCl - AgBr system, containing silver chloride and bromide at the following ratio of ingredients, wt. % : silver chloride - 0.0 to 90.0; silver bromide - 90.0 to 10.0. EFFECT: invention allows to form crystals transmitting emission in a wide spectral range, from terahertz to millimeter, infrared and visible ranges with high optical transparency from non-toxic, non-hygroscopic, plastic materials. 1 cl.Изобретение относится к терагерцовым (ТГц) материалам, а именно к кристаллам востребованных для применения в медицине, фармацевтике, таможенном дистанционном контроле и в других областях. Терагерцовый кристалл согласно изобретению характеризуется тем, что выполнен на основе однофазных твердых растворов системы AgCl - AgBr, содержит хлорида и бромида серебра при следующем соотношении ингредиентов, мас. %: хлорид серебра - 0,0-90,0; бромид серебра - 90,0-10,0. Изобретение обеспечивает возможность формировать кристаллы, пропускающие излучение в широкой спектральной области - от терагерцового до миллиметрового, инфракрасного и видимого диапазонов с высокой оптической прозрачностью из нетоксичных, негигроскопичных, пластичных материалов

A New Method for Treating Burn Wounds Using Targeted Delivery of Medicinal Substances by Magnetic Nanocarrier (Experimental Part)

Проведено экспериментальное исследование на лабораторных животных по изучению эффективности адресной доставки мази левомеколь с помощью магнитных наночастиц и внешнего магнитного поля при термических ожогах. В исследовании принимало участие 20 крыс с двумя очагами ожога. Крысы были разделены на 4 группы: без лечения, терапия с использованием мази левомеколь, лечение с использованием наночастиц, мази левомеколь и внешнего магнитного поля и только магнитотерапии. При гистологическом исследовании на 14-е сутки во всех группах в зоне термического повреждения кожи были отмечены признаки глубокого ожога III и IV степени с распространением некроза на всю глубину дермы и на мышцы. В группе с наночастицами, мазью левомеколь и магнитным полем на фоне уменьшения воспаления отмечалось очаговое появление грануляционной ткани. Таким образом, гистологические исследования ожогового раневого процесса лабораторных животных показали, что использование инновационного биологически активного ранозаживляющего средства на основе наночастиц в сочетании с мазью левомеколь улучшает регенерацию тканей и приводит к ускорению эпителизации, что в целом повышает результаты лечения ожоговой раны. Использование внешнего магнитного поля способствует адресной доставке лечебного нанокомплекса и поддержанию оптимальной концентрации препарата в ранеExperimental studies have been carried out on laboratory animals to investigate the effectiveness of targeted delivery of levomekol ointment using magnetic nanoparticles and an external magnetic field for treatment of thermal burns. The study involved 20 rats, with two burns on each. The rats were divided into 4 groups: untreated; treated with levomekol ointment; treated with levomekol ointment associated with nanoparticles and an external magnetic field; and treated with magnetic field alone. Histological examination was conducted on Day 14, and in all groups, in the thermal burn zone of the skin there were signs of deep three- and four-degree burns with necrosis spread through the dermis, reaching the muscle. In the group with levomekol ointment associated with nanoparticles and magnetic field, inflammation was decreased, and focal granulation tissue formation was observed. Thus, histological studies of the burn wound process in laboratory animals showed that the use of an innovative biologically active wound healing agent based on nanoparticles in combination with the levomecol ointment improved tissue regeneration and accelerated epithelialization, which enhanced the effectiveness of burn wound treatment. The use of an external magnetic field facilitated targeted delivery of the therapeutic nanosystem and maintenance of the optimal concentration of the drug in the woun

Principles for reducing the phase shift between instantaneous analogue and discrete signals and the corresponding values in the sampled values (SV) stream of a digital substation

There are numerous publicly available articles on digital substations, including those dedicated to current and voltage measurements, time synchronization, test systems development, principles of substation design, and other aspects of this topic. But the phase shift between instantaneous signals and the corresponding values in the SV (sampled values) stream has been little discussed. We can list the following principles to reduce the phase shift between instantaneous analogue and discrete signals and the corresponding values in the SV stream. 1) Exclusion from the device, of non-essential elements that introduce additional propagation delays of analogue and discrete signals, provided that such exclusion does not adversely affect the device performance or characteristics. 2) Reduction of the delay time for the other device elements to the minimum values. 3) Adjustment of the delay time of some device elements or addition of special delay elements to equalize the time of signal propagation over analogue and discrete channels. 4) Consideration of the total delay time of signal propagation over analogue and discrete channels and adjustment of the time stamp in the SV frame. The article provides examples of application of these principles in signal generation and measuring devices and phase shift meters

Correlation of hardness and surface microcracking in ITER specification tungsten exposed at QSPA Kh-50

In this work, we have investigated the evolution of the hardness of tungsten under successive thermal shock pulses induced under plasma exposure at quasi-stationary plasma accelerator QSPA-Kh50. The applied conditions represent localized modes of plasma instabilities expected under operation in ITER. The base temperature of 300 °C and deposited heat load of 0.45 MJ/m 2 is known to be close to the cracking threshold, which is chosen in this study on purpose. Nanoindentation and microstructural characterization (identification of microcracks) is applied to the samples exposed to 10, 50, 70 and 100 pulses to reveal ability of nanoindentation technique to capture the threshold for the microcrack formation. Knowing that under the selected exposure conditions, the subsurface region of the material is a subject to the recrystallization, which is induced by the overheating during the plasma discharge, nanoindentation measurements are performed on the same tungsten grade annealed at 1300 °C, 1500 °C and 1800 °C to achieve different degree of recrystallization. It is shown that multiple microcracks appear after the 50 th cycle which correlates with the reduction of the hardness corresponding to the massive grain growth. FEM analysis is applied to identify stress/temperature distribution across the sample depth to clarify the nucleation location, expected to occur in the region with the highest stress concentration close to the ductile to brittle transition temperature

RIMS analysis of Ca and Cr in Genesis solar wind collectors

RIMS depth profiles have been measured for Cr and Ca in Genesis solar wind collector made from Si and compared to such measurements for ion-implanted Si reference material. The presence of surface contamination has been shown to be a significant factor influencing the total Ca and Cr fluence measured in the Genesis collectors. A procedure to remove the contaminant signal from these depth profiles using the reference material implanted with a minor isotope demonstrated that 36% of the measured Ca fluence in our Genesis sample comes from terrestrial contamination