Impact of High-Temperature, High-Pressure Synthesis Conditions on the Formation of the Grain Structure and Strength Properties of Intermetallic Ni[3]Al

The impact of the preliminary load on 3Ni+Al powder mixture and the impact of the duration of the delay in application of compacting pressure to synthesis product under the conditions of continuous heating of the mixture up to its self-ignition on the grain size and strength properties of the synthesized Ni[3]Al intermetallide material have been studied. The grain structure of the intermetallide synthesized under pressure was studied by means of metallography, transmission electron microscopy and EBSD analysis, with the dependence of ultimate tensile strength on the grain size in the synthesized intermetallide having been investigated at room temperature and at temperatures up to 1000°С. It is shown that an increase in the pressure preliminarily applied to the initial mixture compact results in reduced grain size of the final intermetallide, whereas an increase in pre-compaction time makes the grain size increased. A decrease in the grain size increases the ultimate tensile strength of the intermetallide. The maximum value of the ultimate tensile strength in the observed anomalous temperature dependence of this strength exhibits a shift by 200°С toward higher temperatures, and the ultimate strength of the synthesized intermetallide at 1000°С increases roughly two-fold

ПАТОГЕНЕТИЧНЕ ОБҐРУНТУВАННЯ ВИКОРИСТАННЯ ЛОЗАРТАНУ У ХВОРИХ НА ХРОНІЧНУ ХВОРОБУ НИРОК З БЕЗСИМПТОМНОЮ ГІПЕРУРИКЕМІЄЮ

В статье освещается проблема влияния гиперурикемии на развитие и течение сердечно-сосудистой патологии. На основании данных ряда исследований показано, что имеется все больше свидетельств об отрицательном влиянии нетрадиционных факторов риска таких как гиперурикемия, микроальбуминурия и др. на прогноз сердечно-сосудистых заболеваний, в том числе и при хронической болезни почек. Основываясь на результаты клинических исследований показано, что лозартан способен блокировать реабсорбцию мочевой кислоты в проксимальных канальцах почек, снижая уровень мочевой кислоты у пациентов с хроничeской болезнью почек, артериальной гипертензией и бессимптомной гиперурикемией

Закономерности регенерации конъюнктивы и склеры после интраоперационной аппликации раствора циклоспорина А у кроликов со стероидной моделью глаукомы

 Aim. In an in vivo experiment, to study the effect of local intraoperative application of 0.05% cyclosporin A solution on the conjunctival and scleral regeneration after surgery on the rabbit eyes with steroid-induced  glaucoma.Materials and methods. At the first stage of the experiment, a model of steroid-induced glaucoma was reproduced for 29 male Californian rabbits by injecting 0.5 ml of a 0.4% solution of dexamethasone subconjunctivally in both eyes once a week for 3 months (12 subconjunctival injections for each rabbit). At the second stage of the experiment, after the development of  steroid glaucoma, the rabbits were divided into the main group, consisting  of the subgroup «a» (n = 8) and the subgroup «b» (n = 8), and the comparison group (n = 8). All animals were performed a penetrating incision of the conjunctiva and a non-penetrating incision of the sclera of one of the eyes. A hemostatic sponge impregnated with 0.05% cyclosporin А solution was applied to the intervention area in the main group, in the subgroup «a» – for 3 minutes, in the subgroup «b» – for 6 minutes. In the comparison group, the cytostatic was not used.Results. The use of 0.05% cyclosporin А solution led to a decrease in the  infiltration of fibroblasts and inflammatory cells into the area of surgical  injury. On the 4th day after the surgery, cell density in the intervention area  in the subgroup «a» with 3-minute application of cytostatic-antimetabolite solution was 2.7 times lower (p = 0.043) than in the comparison group, while exceeding the values in the subgroup «b» by 3.2 times (p = 0.036). The number of fibroblasts in the subgroups «a» and «b» was 3.6 (p = 0.043) and 12.8 times (p = 0.031) less than in the comparison group, and a shift in the cellular composition of the infiltrate towards the fibroblastic population occurred only on the 14th day after the surgery.Conclusion. Intraoperative application of 0.05% cyclosporin А solution significantly slows down the course of regeneration, reducing infiltrative inflammation in the intervention area, which prevents excessive scarring.  Цель. В эксперименте in vivo изучить влияние местной интраоперационной аппликации 0,05%-го раствора (р-ра) циклоспорина А на регенерацию конъюнктивы и склеры  после операции на глазах кроликов со стероидной  глаукомой.Материалы и методы. На I этапе эксперимента 29 самцам  кроликов калифорнийской породы моделировали  стероидную глаукому путем введения под конъюнктиву  обоих глаз 0,5 мл 0,4%-го р-ра дексаметазона 1 раз в нед в течение 3 мес (12 инъекций). На II этапе эксперимента, после развития стероидной глаукомы, кроликов разделили на основную группу, состоящую из подгруппы «a» (n = 8) и подгруппы «b» (n = 8), и группу сравнения (n = 8). Всем животным выполняли сквозной разрез конъюнктивы и непроникающий надрез склеры одного из глаз. На область вмешательства в основной группе накладывали гемостатическую губку, пропитанную 0,05%-м р-ром циклоспорина А, в подгруппе «а» на 3 мин, в подгруппе «b» – на 6 мин. В группе сравнения цитостатик не использовали.Результаты. Применение 0,05%-го р-ра циклоспорина А  привело к уменьшению инфильтрации зоны хирургической  травмы воспалительными клетками и фибробластами. На 4- е сут после операции клеточная плотность в области вмешательства в подгруппе «а» основной группы с трехминутной аппликацией р-ра цитостатика-антиметаболита была в 2,7 раза меньше (p = 0,043), чем в  группе сравнения, превышая при этом показатели подгруппы «b» в 3,2 раза (p = 0,036). Численность  фибробластов в подгруппах «а» и «b» была в 3,6 (p = 0,043) и 12,8 раза (p = 0,031) ниже, чем в группе сравнения. При  этом сдвиг клеточного состава инфильтрата в сторону  фибробластической популяции произошел только на 14-е  сут после операции. Заключение. Интраоперационная аппликация 0,05%-го р- ра циклоспорина А существенно замедляет течение  воспалительно-репаративной регенерации, уменьшая  инфильтративное воспаление в зоне вмешательства, что  предотвращает излишнее рубцевание.

Peripheral vascular lesions with the development of hand and foot skin necrosis in a patient with COVID-19: a case report

In the presented case report, 36-year-old female patient, who was hospitalized in the rheumatology department, developed thrombotic microangiopathy and sepsis-related coronavirus disease 2019 (COVID-19). In the department, hereditary thrombophilia was revealed: heterozygous polymorphism in the coagulation factor 5 gene (Factor V Leiden). Livedo reticularis. It is known that in October 2020, the patient had COVID-19 with bilateral pneumonitis on chest computed tomography. On examination, dry gangrene of 1, 2, 4, 5 fingers of the right hand, 2 finger of the left hand, as well as 2, 3, 4, 5 fingers of the right and left feet were diagnosed. Necrosis of the nasal tip. Surgery was performed with amputation of the affected fingers and distal feet with autodermoplasty

Enhancement of Raman light scattering in dye-labeled cell membrane on metal-containing conducting polymer film

An enhanced Raman spectroscopy method based on a plasmon resonance in ultrathin metal-containing LB-film deposited on nanoporous anodic alumina supports has been proposed. This material has been utilized to enhance Raman scattering of light in fluorescent-labeled subcellular membrane structures. It has been shown that the plasmon resonance between vibrational modes of the organometallic complexes monolayers and dye-labeled subcellular structures happens. It makes possible to detect interactions between living cell monolayers and an extracellular matrix

Poloxomer 188 Has a Deleterious Effect on Dystrophic Skeletal Muscle Function

Duchenne muscular dystrophy (DMD) is an X-linked, fatal muscle wasting disease for which there is currently no cure and limited palliative treatments. Poloxomer 188 (P188) is a tri-block copolymer that has been proposed as a potential treatment for cardiomyopathy in DMD patients. Despite the reported beneficial effects of P188 on dystrophic cardiac muscle function, the effects of P188 on dystrophic skeletal muscle function are relatively unknown. Mdx mice were injected intraperitoneally with 460 mg/kg or 30 mg/kg P188 dissolved in saline, or saline alone (control). The effect of single-dose and 2-week daily treatment was assessed using a muscle function test on the Tibialis Anterior (TA) muscle in situ in anaesthetised mice. The test comprises a warm up, measurement of the force-frequency relationship and a series of eccentric contractions with a 10% stretch that have previously been shown to cause a drop in maximum force in mdx mice. After 2 weeks of P188 treatment at either 30 or 460 mg/kg/day the drop in maximum force produced following eccentric contractions was significantly greater than that seen in saline treated control mice (P = 0.0001). Two week P188 treatment at either dose did not significantly change the force-frequency relationship or maximum isometric specific force produced by the TA muscle. In conclusion P188 treatment increases susceptibility to contraction-induced injury following eccentric contractions in dystrophic skeletal muscle and hence its suitability as a potential therapeutic for DMD should be reconsidered

Thermal effects of carbonated hydroxyapatite modified by glycine and albumin

In this work calcium phosphate powders were obtained by precipitation method from simulated solutions of synovial fluid containing glycine and albumin. X-ray diffraction and IR spectroscopy determined that all samples are single-phase and are presented by carbonate containing hydroxyapatite (CHA). The thermograms of solid phases of CHA were obtained and analyzed; five stages of transformation in the temperature range of 25-1000°C were marked. It is shown that in this temperature range dehydration, decarboxylation and thermal degradation of amino acid and protein connected to the surface of solid phase occur. The tendency of temperature lowering of the decomposition of powders synthesized from a medium containing organic substances was determined. Results demonstrate a direct dependence between the concentration of the amino acid in a model solution and its content in the solid phase