22 research outputs found

    Железомарганцевые корки горы Петра Великого и хребта Васильковского, Японское море

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    Изучено строение и химический состав железомарганцевых корок, сформированных на осадочном чехле подводных вулканов горы Петра Великого и хребта Васильковского, расположенных у материкового склона Приморья (Японское море). Корки образовались в результате цементации и осаждении на поверхности осадка гидроксидов марганца. Признаками гидротермальности этих образований являются очень высокое значение титанового и низкое алюминиевого модулей, низкие содержания цветных и редкоземельных элементов, превышение содержаний тяжелых РЗЭ над легкими. Отложение рудного вещества произошло, вероятно, в плейстоцен-голоценовое время из поствулканических гидротермальных растворов. В отличие от корок, отложившихся на базальтах в центральных частях Японского моря, эти корки не содержат включений мелких зерен средне- и высокотемпературных минеральных фаз цветных металлов

    MAIN FEATURES OF YOUTH JARGON: SYCHRONIC ANALYSIS

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    The article deals with synchronic analysis of the main characteristic features of youth jargon and their historical determination. The authors disclose and compare such terms as “youth jargon”, “youth slang”, “argot” and analyze some tendencies in their studies

    Effects of High and Low Molecular Weight Hyaluronic Acids on the Omega-3 and Omega-6 Fatty Acid Release upon Activation of the Toll-Like Receptors in Astrocytes

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    Abstract: Hyaluronic acid (HA) is one of the key polymer components of the extracellular matrix; it can exert different effects on intracellular signaling depending on its molecular weight. We compared the effects of low (LMW) and high molecular weight (HMW) HA polymers on the ability of primary astrocytes, glial brain cells, to release into the extracellular medium omega-3 unsaturated fatty acids, docosahexaenoic (DHA) and eicosapentaenoic (EPA), as well as omega-6 unsaturated arachidonic acid (AA), which were determined by HPLC-MS/MS. It was shown that upon the addition of LMW HA for 4.5 h the concentration of AA reduced. HMW HA did not affect the release of AA but increased the release of DHA and EPA. Adaptation of the cells for 48 h to the action of the HA polymers of different molecular weights led to a decrease in the release of omega-3 and omega-6 unsaturated fatty acids by astrocytes. A comparison of the ability of HA to modulate astrocyte responses to stimulation by Toll-like receptor (TLR) agonists showed that HA affected TLR4-stimulated induction of IL-1β proinflammatory marker gene after 0.5-h exposure to LMW HA and HMW HA followed by further stimulation with TLR4 agonist for 4 h. Thus, the release of polyunsaturated fatty acids in astrocytes was sensitive to HA and depended on the molecular weight of the polymers; long (48 h) exposure to HA led to adaptation of astrocytes; HA differently affected the release of omega-6 (AA) and omega-3 (DHA) unsaturated fatty acids, indicating a difference in the mechanisms of their release. As DHA is believed to perform anti-inflammatory and protective functions in the brain, these findings open up prospects for appliance of HA polymers as modulators of inflammatory responses of astrocytes. © 2020, Pleiades Publishing, Ltd

    Sex-mediated differences in lps induced alterations of TNFα, IL-10 expression, and prostaglandin synthesis in primary astrocytes

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    Although many neurological and psychiatric disorders reveal clear sex-dependent variations, the molecular mechanism of this process is not clear enough. Astrocytes are involved in the response of neural tissue to injury and inflammation, produce steroid hormones, and sense steroid presence. To explore the hypothesis that astrocytes may participate in sex-mediated differences of inflammatory responses, we have examined whether male and female primary rat astrocytes show different responses to lipopolysaccharide (LPS) as a toll-like receptor 4 (TLR4) agonist. Levels of mRNA and proteins of tumor necrosis factor alpha (TNFα), interleukin-10 (IL-10), and cyclooxygenase (COX)-2 were assessed using qPCR, immunoblotting, and ELISA. UPLC-MS/MS was used to detect prostaglandins (PGs). LPS stimulation resulted in different levels of cytokine production; more TNFα and less IL-10 were produced in female cells compared with male astrocytes. Although the levels of the COX-2 expression were not altered, LPS significantly induced the synthesis of PGs with notable sex-related differences. PGE2 and PGD2 were less and 6-keto-PGF1α was more upregulated in female astrocytes, and TXB2 had similar levels in cells obtained from males and females. Trilostane, an inhibitor of 3β-Hydroxysteroid dehydrogenase (3β-HSD), inhibited the LPS-induced TNFα production and the release of PGE2, PGD2, and 6-keto-PGF1α in female astrocytes. Thus, male and female astrocytes differentially respond to inflammatory challenges on the level of production of cytokines and steroid hormones. Sex-mediated differences in pro-and anti-inflammatory responses should be taken into consideration for the effective treatment of disorders with neuroinflammation. © 2018 by the authors. Licensee MDPI, Basel, Switzerland

    Sex-mediated differences in lps induced alterations of TNFα, IL-10 expression, and prostaglandin synthesis in primary astrocytes

    No full text
    Although many neurological and psychiatric disorders reveal clear sex-dependent variations, the molecular mechanism of this process is not clear enough. Astrocytes are involved in the response of neural tissue to injury and inflammation, produce steroid hormones, and sense steroid presence. To explore the hypothesis that astrocytes may participate in sex-mediated differences of inflammatory responses, we have examined whether male and female primary rat astrocytes show different responses to lipopolysaccharide (LPS) as a toll-like receptor 4 (TLR4) agonist. Levels of mRNA and proteins of tumor necrosis factor alpha (TNFα), interleukin-10 (IL-10), and cyclooxygenase (COX)-2 were assessed using qPCR, immunoblotting, and ELISA. UPLC-MS/MS was used to detect prostaglandins (PGs). LPS stimulation resulted in different levels of cytokine production; more TNFα and less IL-10 were produced in female cells compared with male astrocytes. Although the levels of the COX-2 expression were not altered, LPS significantly induced the synthesis of PGs with notable sex-related differences. PGE2 and PGD2 were less and 6-keto-PGF1α was more upregulated in female astrocytes, and TXB2 had similar levels in cells obtained from males and females. Trilostane, an inhibitor of 3β-Hydroxysteroid dehydrogenase (3β-HSD), inhibited the LPS-induced TNFα production and the release of PGE2, PGD2, and 6-keto-PGF1α in female astrocytes. Thus, male and female astrocytes differentially respond to inflammatory challenges on the level of production of cytokines and steroid hormones. Sex-mediated differences in pro-and anti-inflammatory responses should be taken into consideration for the effective treatment of disorders with neuroinflammation. © 2018 by the authors. Licensee MDPI, Basel, Switzerland

    High and low molecular weight hyaluronic acid differentially influences oxylipins synthesis in course of neuroinflammation

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    Hyaluronic acid (HA), a major glycosaminoglycan of the extracellular matrix, has cell signaling functions that are dependent on its molecular weight. Anti-inflammatory effects for high-molecular-weight (HMW) HA and pro-inflammatory effects for low-molecular-weight (LMW) HA effects were found for various myeloid cells, including microglia. Astrocytes are cells of ectodermal origin that play a pivotal role in brain inflammation, but the link between HA with different molecular weights and an inflammatory response in these cells is not clear. We tested the effects of LMW and HMW HA in rat primary astrocytes, stimulated with Poly:IC (PIC, TLR3 agonist) and lipopolysaccharide (LPS, TLR4 agonist). Oxylipin profiles were measured by the UPLC-MS/MS analysis and metabolites HDoHEs (from docosahexaenoic acid),-HETEs, prostaglandins (from arachidonic acid), DiHOMEs and HODEs (from linoleic acid) were detected. Both, HMW and LMW HA downregulated the cyclooxygenase-mediated polyunsaturated fatty acids metabolism, LMW also reduced lipoxygenase-mediated fatty acid metabolism. Taken together, the data show that both LMW and HMW (i) influence themselves on cytokines (TNFα, IL-6, IL-10), enzymes iNOS, COX-2, and oxylipin levels in extracellular medium of cultured astrocytes, (ii) induced cellular adaptations in long-term applications, (iii) modulate TLR4-and TLR3-signaling pathways. The effects of HMW and LMW HA are predominantly revealed in TLR4– and TLR3-mediated responses, respectively. © 2019 by the authors. Licensee MDPI, Basel, Switzerland

    Cellular Model of Endotoxin Tolerance in Astrocytes: Role of Interleukin 10 and Oxylipins

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    A phenomenon of endotoxin tolerance where prior exposure of cells to minute amounts of lipopolysaccharide (LPS) causes them to become refractory to a subsequent high-amount endotoxin challenge is well described for innate immune cells such as monocytes/macrophages, but it is still obscure for brain cells. We exposed primary rat cortical astrocytes to a long-term low-grade concentration of LPS, followed by stimulation with a middle-grade concentration of LPS. Inflammatory markers, i.e., pro-inflammatory cytokine TNF alpha, inducible enzymes COX-2 and iNOS, anti-inflammatory cytokine interleukin 10 (IL-10) detected at the mRNA and protein levels reveal similarities between astrocytes and macrophages in the model, i.e., tolerance in pro-inflammatory markers and priming in IL-10. Long-term or short-term treatment with IL-10 does not change cell sensitivity for LPS, which makes doubtful its involvement in the mechanisms of cell tolerance development. Significant changes occur in the oxylipin profiles measured by UPLC-MS/MS analysis. The priming occurs in the following compounds: 11-HETE, PGD(2), PGE(2), cyclopentenone prostaglandins, and TXB2. Tolerance is observed for 12-HHT, PGF(2 alpha), and 6-keto-PGF(1 alpha). As far as we know, this is the first report on changes in oxylipin profiles in the endotoxin tolerance model. The data can greatly improve the understanding of oxylipins' role in inflammatory and resolution processes in the brain and mechanisms of astrocyte involvement in neuroinflammation
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