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This study examines the relative impact of canonical hypoxia-inducible factor-1alpha- (HIF-1α and Na+i/K+i-mediated signaling on transcriptomic changes evoked by hypoxia and glucose deprivation. Incubation of RASMC in ischemic conditions resulted in ∼3-fold elevation of [Na+]i and 2-fold reduction of [K+]i. Using global gene expression profiling we found that Na+,K+-ATPase inhibition by ouabain or K+-free medium in rat aortic vascular smooth muscle cells (RASMC) led to the differential expression of dozens of genes whose altered expression was previously detected in cells subjected to hypoxia and ischemia/reperfusion. For further investigations, we selected Cyp1a1, Fos, Atf3, Klf10, Ptgs2, Nr4a1, Per2 and Hes1, i.e. genes possessing the highest increments of expression under sustained Na+,K+-ATPase inhibition and whose implication in the pathogenesis of hypoxia was proved in previous studies. In ouabain-treated RASMC, low-Na+, high-K+ medium abolished amplification of the [Na+]i/[K+]i ratio as well as the increased expression of all tested genes. In cells subjected to hypoxia and glucose deprivation, dissipation of the transmembrane gradient of Na+ and K+ completely eliminated increment of Fos, Atf3, Ptgs2 and Per2 mRNAs and sharply diminished augmentation expression of Klf10, Edn1, Nr4a1 and Hes1. In contrast to low-Na+, high-K+ medium, RASMC transfection with Hif-1a siRNA attenuated increments of Vegfa, Edn1, Klf10 and Nr4a1 mRNAs triggered by hypoxia but did not impact Fos, Atf3, Ptgs2 and Per2 expression. Thus, our investigation demonstrates, for the first time, that Na+i/K+i-mediated, Hif-1α- -independent excitation-transcription coupling contributes to transcriptomic changes evoked in RASMC by hypoxia and glucose deprivation. [ABSTRACT FROM AUTHOR]

An overview of the last works concerning the Recent environment and bottom sediments in the White Sea is presented. Special attention is devoted to the existing schemes of the modern facies structure. Up-to-date factual material allowed the authors to offer a new version of the facies structure. According to this version, the White Sea can be divided into two areas (scale 1 : 5 000 000): Northeastern and Southwestern. The Northeastern facies area includes two facies zones: Western and Eastern. The Southwestern facies area includes three facies zones: Central, Transitional, and Peripheral. In turn, the Peripheral facies zone is divided into the following facies subzones: (1) shallow-water Kandalaksha Bay; (2) Onega Bay, and (3) Severnaya Dvina prodelta and the Letnii Coast. Typical peculiarities of the Recent depositional environment and accumulated marine sediments are presented for all facies areas, zones and subzones. [ABSTRACT FROM AUTHOR]

In the geochemical review based on records from cruises of the International Deep Marine Drilling Project (DSDP, ODP, and IODP phases) and other literature data on the main types of Pleistocene sediments in the Atlantic, tables of average arithmetic chemical composition, mean weighted chemical composition, accumulation rates, and mass accumulation rates of chemical components are presented. These tables can be used for the comparative analysis with sediments of the same or other stratons in different oceanic basins, as well as with paleoceanic sediments on the continents. The terrigenous matrix dominates within the lithogenic matter. Using methods of mathematical statistics, we revealed the main geochemical associations and major factors determining the chemical composition of studied sediments. Masses of oxides of petrogenic elements and several trace elements have been calculated for Pleistocene sediments. Average chemical composition of Pleistocene sediments is proposed for the Atlantic. [ABSTRACT FROM AUTHOR]

Abstract—Lithological–facies zonality of Neo– and Eopleistocene sediments from the Fiji Sea is described for the first time. Processing of corresponding maps and isopachite schemes using A.B. Ronov's volumetric method gave us an opportunity to calculate the quantitative parameters of sedimentation for distinguished types of Pleistocene sediments. Carbonate sediments dominate over other groups of sediments. Carbonate planktonic sediments have been more intensively accumulated in the Neopleistocene than in the Eopleistocene. The highest volcanotectonic activity is typical of Eopleistocene. [ABSTRACT FROM AUTHOR]

A geochemical review of Pleistocene sediments in the Indian Ocean has been accomplished based on the deep-sea drilling cruise reports and other literature references. We compiled the database including more than 2000 chemical analyses of sediment samples and tables showing the mean arithmetic composition of lithogenic and biogenic sediments. All data were PAAS-normalized. The dominant role of terrigenous clastics is revealed in the formation of the chemical composition of noncarbonate sediments and noncarbonate matter in planktonic carbonates. The results made it possible to establish the main geochemical associations together with three main (terrigenous, carbonate, and hydrogenous) factors determinating the sediment composition. We calculated the weighted mean chemical composition, as well as the element accumulation rate in the sediments and their mass accumulation rates. All these parameters of the chemical composition can be used for the comparative analysis, with analogous parameters in other ocean sediments within Pleistocene straton in the World Ocean. [ABSTRACT FROM AUTHOR]

Abstract—Lithological and facies zonality of Neopleistocene and Eopleistocene sediments of the Australian seas is described for the first time. Processing of these maps and isopach schemes by A.B. Ronov volumetric method gave us an opportunity to calculate the quantitative parameters of sedimentation for different types of the Pleistocene sediments. It was revealed that carbonate sediments predominate over other sediment groups. The Neopleistocene was characterized by more intense accumulation of carbonate planktic sediments and lithogenic sediments than Eopleistocene. [ABSTRACT FROM AUTHOR]

We performed a comparative analysis of quantitative parameters for Pleistocene sediments from the pelagic zone and submarine parts of continental margins of the Atlantic Ocean in seven key areas. In the Neopleistocene compared to the Eopleistocene, the lithogenic fluxes increased both in the pelagic zone and on the continental margins. The residual absolute masses of СаСО3 and biogenic opal decreased in both megafacies zones. The biogenic sedimentation was more important for facies structure of the pelagic zone than for continental margins. [ABSTRACT FROM AUTHOR]

We have done a comparative analysis of quantitative parameters for Pleistocene sediments from pelagic zone of the Indian Ocean and submarine parts of its continental margins (for five key areas). The distribution areas, thicknesses, and volumes of main lithological types and groups have been analyzed. Dry sediment masses and their accumulation rates have been calculated. In the Neopleistocene compared to Eopleistocene, the fluxes (absolute masses) of all components of bottom sediments have been increased both in the pelagic zone and on the continental margins. Biogenic sedimentation was more important for facies structure of pelagic zone than (on average) for continental margins. [ABSTRACT FROM AUTHOR]

A comparative analysis of two large Arctic sedimentary basins was performed: the Sverdrup and East Barents, with emphasis on the quantitative parameters of sedimentation in the Mesozoic, determined by A.B. Ronov's volumetric method. The similarities and differences of both basins are revealed, in particular, in sediment accumulation areas, in masses of sedimentary material per time unit, and in gross sand ratio. It was concluded that at the end of the Paleozoic and in the Mesozoic, both basins were close to each other but did not merge into one structure. In the Cenozoic, the distance between the basins increased due to spreading of the Eurasian Basin. [ABSTRACT FROM AUTHOR]

Recent studies demonstrated that in addition to Na+,K+-ATPase inhibition cardiotonic steroids (CTSs) affect diverse intracellular signaling pathways. This study examines the relative impact of [Na+]i/[K+]i-mediated and -independent signaling in transcriptomic changes triggered by the endogenous CTSs ouabain and marinobufagenin (MBG) in human umbilical vein endothelial cells (HUVEC). We noted that prolongation of incubation increased the apparent affinity for ouabain estimated by the loss of [K+]i and gain of [Na+]i. Six hour exposure of HUVEC to 100 and 3,000 nM ouabain resulted in elevation of the [Na+]i/[K+]i ratio by ~15 and 80-fold and differential expression of 258 and 2185 transcripts, respectively. Neither [Na+]i/[K+]i ratio nor transcriptome were affected by 6-h incubation with 30 nM ouabain. The 96-h incubation with 3 nM ouabain or 30 nM MBG elevated the [Na+]i/[K+]i ratio by ~14 and 3-fold and led to differential expression of 880 and 484 transcripts, respectively. These parameters were not changed after 96-h incubation with 1 nM ouabain or 10 nM MBG. Thus, our results demonstrate that elevation of the [Na+]i/[K+]i ratio is an obligatory step for transcriptomic changes evoked by CTS in HUVEC. The molecular origin of upstream [Na+]i/[K+]i sensors involved in transcription regulation should be identified in forthcoming studies. [ABSTRACT FROM AUTHOR]