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Objectives. Biogenic polyamines are widely present in nature. They are characteristic of both protozoan cells and multicellular organisms. These compounds have a wide range of biological functions and are necessary for normal growth and development of cells. Violation of polyamine homeostasis can cause significant abnormalities in cell functioning, provoking various pathological processes, including oncological and neuropsychiatric diseases. The impact on the “polyamine pathway” is an attractive basis for the creation of many pharmacological agents with a diverse spectrum of action. The purpose of this review is to summarize the results of the studies devoted to understanding the biological activity of compounds of the polyamine series, comparing their biological action with action on certain molecular targets. Due to the structural diversity of this group of substances, it is impossible to fully reflect the currently available data in one review. Therefore, in this work, the main attention is paid to the derivatives, acyclic saturated polyamines.Results. The following aspects are considered: biological functionality, biosynthesis and catabolism, cell transport, and localization of biogenic polyamines in the living systems. Structural analogs and derivatives of biogenic polyamines with antitumor, neuroprotective, antiarrhythmic, antiparasitic, antibacterial, and other biological activities are represented; the relationship between biological activity and the target of exposure is reflected. It was found that the nature of the substituent, the number of cationic centers, and the length of the polyamine chain have a great influence on the nature of the effect.Conclusions. At present, the use of polyamine structures is restrained by cytotoxicity and nonspecific toxic effects on the central nervous system. Further research in the field of biochemistry, cell transport, and a deeper understanding of receptor interaction mechanisms will help making polyamines as the basis for potential drug formulation.

It was established that at the cathodic treatment of titanium in aqueous dimethyl sulfoxide solutions of sodium molybdate, containing phosphoric acid, at the potential of the cathodic incorporation of sodium (Ec = − 2.6 V) in the potentiostatic mode, the composition formed on the electrode surface layer depended not only on the composition of the solution, but also on the volume ratio of the aqueous electrolyte solution and the organic solvent (dimethyl sulfoxide).

The possibility of using microwave radiation at various stages of obtaining an unsaturated polyester composite modified with carbon nanotubes was studied. The optimal content of MWCNTs in the system was experimentally selected, having the best effect on the strength of the composite. The effect of the microwave field on the properties of a polyester composite during the microwave treatment of an oligomer, a polymerized composite, and MWCNTs before their addition into the oligomer was studied. The processes of the structure formation, the structure of the composite, the effect of the microwave radiation on MWCNTs, and the thermal stability of the resulting composites were considered.

. The purpose of the article is to assess energy efficiency of the expander generator application in cogeneration systems. It demonstrates that the research works devoted to this subject do not take into account the effect that gas parameters after the expander have on operating efficiency of the main power generating equipment that leads to a distortion of the assessment of expander energy efficiency. The energy efficiency is determined by specific fuel savings resulting from the use of a circuit with an expander compared to the option of gas throttling. It shows that spe-cific fuel saving is directly proportional to the increment value of the total specific useful work of the utility company when using expander generators. It was found that when using the ex-pander at the cogeneration plant the total specific useful work increment is less than the specific work of the expander generator. It is shown that the energy effect magnitude from the use of circuits with an expander at cogeneration boilers depends on the ambient air temperature. For an expander at cogeneration boiler houses with gas piston internal combustion engines at air tem-peratures below the optimum mixture temperature, the total increment of the specific work is equal to the specific work of the expander, at higher temperatures, the increment of the total specific work can be several times greater than the specific work of the expander. The prospects of preheating gas before the expander at the considered utility companies were analyzed.

The possibility of using graphene oxide as a modifying additive for polymer fiber-reinforced composites based on epoxy resin and basalt roving has been studied. The content of graphene oxide in the system has been experimentally selected, which has the best effect on the physico-mechanical properties of the obtained polymer composite material. The efficiency of the modification of the graphene oxide surface with APTES finishing additives and aminoacetic acid, which provides chemical interaction at the polymer matrix–filler interface, has been considered. The influence of graphene oxide and functionalizing additives on the polymer curing process was investigated using the thermometric method and differential scanning calorimetry.

The baseline levels of proinflammatory mediators (high-sensitivity C-reactive protein, Interleukin-6) and markers of endothelial damage (endothelin-1, von Willebrand factor ) in the blood serum were measured in 128 patients with atherosclerosis of the lower extremities who had underwent balloon angioplasty. Hemodynamically significant restenosis in patients with lesions of the iliac arteries was observed in 34% of patients, with the postoperative loss of the lumen being equal to 58.34.29%, while in the group of patients with stenosis of the femoral and popliteal arteries it accounted for 46%, with the postoperative loss of the lumen reaching 65.25.14%. A direct correlation between the level of indicators of proinflammatory mediators, markers of endothelial damage and the degree of ischemia of the lower extremities was identified. Also determined were the predictors of restenosis formation after angioplasty of the lower extremity arteries. The level of CRP tended to exceed 10.1 mg/l, IL-6 was over 6.1 pg/ml and ET-1 was higher than 0.8 ng/ml.

For a long time, the thermal history of northeastern (NE) Fennoscandia in the Phanerozoic and Precambrian remained unknown, since no thermochronological studies were carried out within the Kola Peninsula area. Two years ago, we developed the first model of tectono-thermal evolution of the Kola Peninsula territory for the last 1.9 Gyr using a set of newly obtained apatite fission-track (AFT) and Ar/Ar thermochronological data. However, the low-temperature history of the most ancient tectonic unit of the northeastern part of the Kola Peninsula—the Archean Murmansk craton—remained poorly constrained due to the lack of AFT data. In this paper, we present the first results of AFT studies of 14 samples representing intrusive and metamorphic Precambrian rocks, located within the Murmansk craton of NE Fennoscandia. AFT ages and track length distributions indicate a similar tectono-thermal evolution of Precambrian tectonic units in NE Fennoscandia over the last 300 Myr. The AFT ages are distributed between ca. 177 and ca. 384 Ma; their median value, ~293 Ma, confirms the presence of a previously identified hidden thermal event that took place at about 300 Ma. However, a detailed analysis of the AFT age distribution shows the presence of three statistically distinguishable age components: 180–190 Ma (C1), 290–320 Ma (C2) and 422 Ma (C3). We assume that the relatively young AFT ages of C1 may originate from apatite crystals with low thermal resistivity. Remarkably, this value coincides with the initial stage of the Barents Sea magmatic province activity during large-scale plume-lithospheric interaction, as well as with the assumed age of an enigmatic remagnetization event throughout the Kola Peninsula. C2 ages can be observed in both the gabbroic and non-gabbroic samples, whereas C3 ages can only be found in gabbro. It is supposed that C2 ages, similarly to the Central Kola terrane, correspond to a cooling event related to the denudation of a thick sedimentary cover, representing a continuation of the Caledonian foreland basin towards NE Fennoscandia. C3 ages may be associated with a thermal event corresponding to the Caledonian collisional orogeny.

Проведен ретроспективный анализ результатов эндоваскулярного лечения 52 пациентов с 57 мешотчатыми аневризмами сосудов головного мозга, которым выполнено 55 эндоваскулярных вмешательств. Тотальной эмболизации (тип А) удалось достигнуть у 77% больных, эмболизация типа В выполнена в 19% случаев, неполная эмболизация (тип С) имела место в 4% случаев. В острейшем периоде субарахноидальных кровоизлияний были прооперированы 14 (26,9%) пациентов. Сделаны выводы об эффективности и относительной безопасности внутрисосудистого выключения аневризм, необходимости дифференцированного подхода к тактике оперативного лечения больных в остром периоде геморрагического инсульта после разрыва мешотчатой аневризмы головного мозга.

During the period from 2004 to 2014, prostatic artery embolization was performed in 59 patients with benign prostatic hyperplasia (BPH) and superselective chemoembolization in 36 patients with prostate cancer. After the embolization in BPH cases, the number of symptoms according to IPSS significantly decreased, and Qmax increased. The volume of the prostate and hyperplastic lesions decreased on the average by 53% and 47% on the average, respectively. The positive effect of chemoembolization was achieved in 30 patients (83.3%). The objective response was observed by the reduced PSA levels, prostate volume reduction and the improvement of urination parameters.In 12 months, check biopsy was performed in 16 patients. In 12 cases, fibrosis and epithelial dystrophy without atypia signs were observed, in 2 cases, therapeutic pathomorphism was observed.The application of the methods of embolization in BHP cases and chemoembolization in localized prostate cancer cases has showed their high effectiveness and safety in the patients who are not amenable to conventional therapy.

The synthesis of a series of N-substituted arylheteraaliphatic amino amides was carried out to determine their antiarrhythmic activity. Styrene oxide was the initial compound for the synthesis. Its oxirane ring was opened with N,N-dialkylaminoethanols in the presence of alcoholates. It was found that the opening of the oxirane ring was carried out mainly according to the Krasusky rule on the bond between the oxygen atom and the less substituted carbon atom. A mixture of two products with the predominance of the secondary amino alcohol was created. The main product was separated by multiple vacuum distillations. 2-[2-(Dialkylamino) ethoxy]-1-phenylethanols were obtained and used in the Ritter reaction for the alkylation of benzonitrile in the presence of sulfuric acid to give N-{2-[2-(dialkylamino)ethoxy]-1-phenylethyl} benzamides. Biological tests of the obtained compounds were carried on the aconitine arrhythmia model out in rats. Procainamide, Quinidine, Lidocaine and Ethacyzin were used as the drugs. The findings in this study indicate that most of the obtained compounds have a low toxicity and expressed antiarrhythmic activity.