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The relationship between dietary sodium, hypertension, and cardiovascular injury is far from clear. One of the important links in this process can be microRNAs that have the ability to modulate gene expression at the post-transcriptional level. However, their role in this process has not been fully studied. In addition, further studies require the identification of structural changes in the myocardium in conditions of long-term consumption of a high-salt diet. The aim of the study was to evaluate the expression levels of nuclear transcription factor κB (NFκB), microRNA (miRNA)-21 and structural changes in the myocardium during long-term consumption of a diet containing 8% (high) sodium chloride in Wistar rats. Material and methods. 20 Wistar rats with initial body weight 280.5±42.7 g were divided into two equal groups. The high salt (HS) group received 8% NaCl in the diet, the control (NS) group received the standard diet (0.34% NaCl). After 4 months, systolic blood pressure was measured in rats using the cuff method on the tail; the myocardial mass index was assessed after dissection; histological and electron microscopic examination of the myocardium was performed, and the expression levels of miRNA-21 and NFκB in the myocardium were determined. Results and discussion. Consumption of a diet high in sodium chloride for 4 months did not significantly affect the level of systolic blood pressure in normotensive Wistar rats, but led to an increase in myocardial mass index by 25.0% (p<0.05). In the HS group, hypertrophy of cardiomyocytes and an increase in the wall thickness of arterial vessels were revealed. The area of perivascular fibrosis in rats of the HS-group was almost 1.8 fold higher than in the NS-group. In animals of HS-group, the relative levels of expression of NFκB (more than 2 times) and miRNA-21 (almost 6 times) increased compared with the control. It can be assumed that the negative impact on the cardiovascular system of high-salt diets is partially realized through NFκB-associated signaling pathways and miRNA-21 activation. Conclusion. In Wistar rats, long-term use of a high-salt diet results in myocardial remodeling that is not associated with changes in blood pressure. At the same time, the adverse effects of high salt intake on the myocardium are mediated, in particular, by postgenomic mechanisms, namely an increase in the expression levels of NFκB and microRNA-21.

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Morphological properties and the size of microvesicles were assessed using atomic force microscopy, electron microscopy, and granulometric analysis. As these methods require significant numbers of microvesicles, we chose microvesicles derived from cell lines for our research.

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Extracellular vesicles are subspherical membranous structures secreted by cells and enriched with different types of biological molecules. The number and the molecular content of these structures depend on pathological conditions and the physiological state of the organism. Extracellular vesicles play an important role in intercellular communication and represent potential disease biomarkers. However, mechanisms of formation, functions and morphological characteristics of extracellular vesicles are still studied insufficiently. Low voltage scanning electron microscopy is a promising method to investigate extracellular vesicles, since it does not require conductive coating and therefore enables a high-resolution visualization of morphological details of nanosized objects. This paper presents the results of low voltage scanning electron microscopy study of morphology and size of objects from blood plasma fractions.

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We studied the effect of two pectic polysaccharides PS-B1-AG and PS-B2-RG that were contained in total polysaccharides extracted from Betula pendula leaves on NO production by mouse macrophages and the contribution of signaling molecules to macrophage activation by the test substances. Unlike the total sample, pectins produced a NO-stimulating effect on macrophages. The effect of PS-B2-RG (10 µg/ml) did not differ from the effect of LPS, while PS-B1-AG produced this effect only in a concentration of 20 µg/ml, which was probably due to differences in the chemical structure of the test substances. The studied pectin polysaccharides activated transcription factor NF-κB, kinases p38 and PI3, and cAMP as a negative regulator. These results indicate that Betula pendula polysaccharides are promising substances for creation of immunomodulating drugs.

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Pronounced regenerative effects of alkaloid napelline extracted from Aconitum baicalense on granulocytic hemopoiesis were revealed in the model of cytostatic myelosuppression. Activation of functions of hemopoietic progenitor cells along with increased feeder capacity of the stromal elements in the hemopoiesis inducing microenvironment with decreased levels mesenchymal progenitor cells in the bone marrow are the mechanisms underlying the hemostimulating action of this substance.

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We studied the capacity of IKK-2 inhibitor ([5-(p-fluorophenyl)-2-ureido] thiophene-3-carboxamide) and non-steroidal anti-inflammatory drug voltaren to reduce the severity of local inflammation in Th1- and Th2-type immune response. The test substances (inhibitor in concentrations from 2×10(-13)to 2×10(-16)M and 9.8×10(-4)M voltaren) were shown to reduce edema caused by sheep erythrocytes (Th1-type immune response) and local immediate-type hypersensitivity response (Th2-type immune response). The anti-inflammatory effects of IKK-2 inhibitor in Th1-type immune response were similar to those of voltaren.

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We compared the effect of NF-κB inhibitor aurothiomalate and voltaren on local inflammation in different types of immune response. Both substances reduced edema caused by sheep erythrocytes (Th1-type immune response) and local immediate-type hypersensitivity response induced with ovalbumin (Th2-dependent response). The anti-inflammatory effects of aurothiomalate were similar to those of voltaren during Th1-type immune response.

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Macrophage activity was studied after treatment with hybrid molecules obtained by condensation of terpenic acid residues (betulinic and betulonic acids) and α-tocopherol analogues (α-tocopherol hemisuccinate and Trolox acid). As distinct from betulinic acid and α-tocopherol hemisuccinate, hybrid molecules did not exhibit cytotoxicity in relation to mouse peritoneal macrophages in the MTT test. Test substances inhibited the production of NO by mouse peritoneal macrophages. However, hybrid molecules had no effect on activity of macrophage arginase. Our results indicate that new molecules have anti-inflammatory activity. It can be hypothesized that these substances have immunomodulatory properties.

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We compared the effects of NF-κB inhibitor aurothiomalate and voltaren on NO production by mouse macrophages in vitro, their ability to cause local edema at the site of injection, and their effect on carrageenan-induced inflammation. High concentrations of aurothiomalate reduced NO production, while in low concentrations both aurothiomalate and voltaren stimulated this process. When injected into mouse footpad, aurothiomalate in a dose >1 mM and voltaren in a dose >1.6 µM induce paw edema. Both compounds suppressed carrageenan-induced inflammation, but the efficacy of aurothiomalate 2-fold exceeded that of voltaren.

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The article covers clinical and ophthalmologic characteristics of oculomotor disturbances in myastenic patients with endocrine ophtalmopathy, and differential diagnostic signs and peculiarities of endocrine ophtalmopathy in patients with a combination of the two diseases.

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Male generative buds of the Siberian larch have no organic quiescence during the autumn-winter period and are capable of completing the development of male generative structures under favorable conditions. When microsporophylls of the Siberian larch were cultivated on medium MS with 0.2 mg/l 2,4-D, embryoids of two types were obtained: directly from the microspore body and via formation of organogenic callus. This means that in the Siberian larch, direct and indirect androgenesis in vitro is possible. The Siberian larch pollen was first germinated in vitro, which was enhanced by pretreatment with hydrogen peroxide.

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Contusions of the eyeball involve reactive or secondary changes in intraocular pressure. Clinical examinations of 151 patients with contusion disorders in ophthalmic tone revealed reactive hypertension in 6.62%, reactive hypotone in 31.79%, secondary hypertension in 48.34%, and stable hypotone of the injured eye in 15.89% cases. Secondary changes in intraocular pressure were caused by massive intraocular hemorrhages and structural injuries to the eyeball. The main cause of reactive hypotone resulting from blunt injury to the eye was exfusion, detachment of the vascular membrane diagnosed at that period by ultrasonic examination in 76.92% cases. The main factors responsible for the postcontusion reactive syndrome are changes occurring within a very short period of time, intraocular pressure differences, and "loss" of the threshold volume of the anterior chamber humor because of its discharge during the shock, and activation of the kallikrein-kinin system with release of kinins causing capillary dilatation and increasing capillary wall permeability in the presence of low activity of angiotensin-converting enzyme which destroys bradykinin.

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The reliability theory model of aging (Kol'tover 1981, 1982) was used for analysis of life-tables of Swedish males and females for 1951-1955, 1962-1973 and 1971-1975 calendar years. In terms of the model it has been possible 1) to explain the Gompertz "law" of mortality; 2) to describe quantitatively statistical life-table data including Gompertz's and geriatric ages; 3) to predict the behavior of mortality rate function depending on the extent of population heterogeneity, among them the existence, at respective degrees of heterogeneity, of a maximum in geriatric age range and 4) to estimate the species-specific maximum life-span potential of animals.

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Alpha-glycerophosphate dehydrogenase (alpha-GPD) and succinate dehydrogenase (SD) activities were investigated in lymphocytes from peripheral blood of normal rats and rats bearing the Walker 256 carcinosarcoma. Computer analysis using an original algorithm revealed a hierarchy of biorhythmic patterns of dehydrogenase activities. In all rats, mean SD activity was higher than mean alpha-GPD activity. In rats without tumor, SD and alpha-GPD activities were both higher than in rats with the Walker tumor. Biorhythm spectra for both dehydrogenases were very similar in rats with or without tumor, but tumor implantation resulted in a change of the phase relationship between alpha-GPD and SD.

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Diffusion kinetics model of development of solid tumor has been proposed. This model allows qualitative description of a number of experimental effects, e.g. formation of necrosis zones, change of exponential growth to linear one. Critical parameters for transfer from tumor stabilization mode to its growth have been obtained. Methods of calculation have been elaborated and model calculations have been carried out.

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In a series of experiments the alpha-glycerophosphate dehydrogenase and succinate dehydrogenase (SDH) activities were daily determined simultaneously by the cytochemical method in peripheral blood lymphocytes of normal rats and those with the Walker carcinosarcoma. Using an original algorithm a hierarchy of biorhythms was singled out by a computer according to individual changes in the dehydrogenase activity for each rat. The mean level of succinate dehydrogenase activity was higher than that of alpha-glycerophosphate dehydrogenase. A set of discovered biorhythms and their representation were identical in the both enzymes. The tumor transplantation caused changes in the phase coordination of investigated dehydrogenases in all rhythms and promoted an increase of the succinate dehydrogenase amplitude as compared with the alpha-glycerophosphate dehydrogenase amplitude in certain rhythms. It is concluded that biorhythmological parameters of these enzymes may be used for characterization of the tumor-bearing host.

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The results of the overtime combined clinico-laboratory investigations have evidenced a high medical effectiveness of red blood cell pack transfusions in the treatment of anemia in patients with varying diseases of internal organs.

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