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Bio-optical data, obtained during six cruises in the Black Sea carried out during periods of seasonal stratification in years between 1996 and 2016, have been used to parametrize phytoplankton light absorption () in the deep chlorophyll maximum (DCM) layer located near the bottom of euphotic zone. Relationships between and the sum of chlorophyll-a and phaeopigment concentrations (Chl-a) differed from those for the summertime upper mixed layer (UML). Notably, chlorophyll a specific absorption coefficients () were lower in the DCM and more comparable with values typical for winter phytoplankton in the Black Sea. The spectral shapes in the DCM differed markedly from those in winter and in the summer UML, due to a shoulder at ~490 nm and a local maximum at ~550 nm corresponding to the absorption bands of phycourobilin and phycoerythrobilin. Light absorbing properties of phytoplankton in the DCM (amplitude and spectral shape of ) reflected physiological acclimation to local conditions on the cellular level and population shifts leading to changes in the biomass-dominant species, with Synechococcus spp. domination in the DCM. The parameterization of phytoplankton absorption in the DCM will enable refined spectral models of the downwelling radiance and primary production in the Black Sea. [ABSTRACT FROM AUTHOR]

Abstract: The Marine Strategy Framework Directive (MSFD) aims to achieve Good Environmental Status (GES) in Europe''s Seas. The requirement for regional sea authorities to identify and prioritise issues for management has meant that standardized methods to assess the current level of departure from GES are needed. The methodology presented here provides a means by which existing information describing the status of ecosystem components of a regional sea can be used to determine the effort required to achieve GES. A risk assessment framework was developed to score departure from GES for 10 out of the 11 GES descriptors, based on proposed definitions of ‘good’ status, and current knowledge of environmental status in each of the four regional seas (North-East Atlantic, Mediterranean Sea, Baltic Sea and Black Sea). This provides an approach for regional evaluation of environmental issues and national prioritisation of conservation objectives. Departure from GES definitions is described as ‘high’, ‘moderate’ or ‘low’ and the implications for management options and national policy decisions are discussed. While the criteria used in this study were developed specifically for application toward MSFD objectives, with modification the approach could be applied to evaluate other high-level social, economic or environmental objectives. [Copyright &y& Elsevier]

Failure of intestinal barrier function and subsequent translocation of microorganisms and their degradation products play a decisive role in development of systemic septic complications for many systemic and intra-abdominal pathologies, for example, following obstructive colonic ileus (OCI). This study was aimed at the evaluation of the intestinal barrier state in OCI. Sixty albino Wistar rats weighting 250 to 300 g (mean 265 g) were divided into four groups (15 animals in each). Acute colonic ileus (ACI) was modeled as follows except a control group (Group 1). Our objective was to examine changes in bacterial flora in the abdomen, mesenteric lymphatic nodes (MLN), liver, spleen, and lungs during the model of OCI after 72 hours following the beginning of experiment. The composition of parietal mucus in normal and in OCI 48 hours following the beginning of experiment examined. Interleukin (IL-VI) levels were determined in both portal and peripheral blood. The right-hand half of colon was ligated at the level of ileocaecal junction in animals of Group 2 (n = 15), whereas in animals of Group 3 (n = 15) it was ligated at the level of sigmoid colon. With the same purpose, a portion of the suspended caecal content was administered into lumen of the jejunum at a concentration of 10(6) colony-forming units (CFU) in animals of Group 4 (n = 15). Experimentally--induced OCI causes significant bacterial translocation (BT) in rats. The process of colonization of the proximal small intestine with colonic flora takes place under the conditions of ileus. The conditions favorable for the development of BT are generated with colonization of 10(6) CFU in volume. As a result, intestinal flora penetrates into the abdominal organs and lungs. Its highest concentrations are noted in the lymph nodes, lungs and liver. The modeling of the small intestine colonization with colonic flora (Group 4) demonstrates critical parameters of microbial semination.

The study comprised surgical patients presenting with tumours of the extrahepatic biliferous ducts. The above patients revealed a high activity of gamma-glutamyltransferase, alkaline phosphatase at the expense of the hepatic isoenzye, to a lesser extent--of asparaginaminotransferase, alaninaminotransferase, a high level of conjugated bilirubin, an insignificant increase in the level of cholesterol and triglycerides. The above biochemical indices combined with results of other methods of investigation can be used for early diagnosis of mechanical jaundice of the tumour genesis.

Thiamine has been shown to be bound specifically by a synaptosomal plasmatic membrane and transported inside to the nervous ending. Apparent K[symbol: see text] and Km for processes of binding and transport have been determined as equal 2.34 +/- 0.55 MKM and 3.92 +/- 1.3 MKM, respectively. The thiamine uptake by the isolated nervous endings (synaptosomes) at its physiological concentration is reduced in presence of metabolic inhibitors and partially depends on Mg2+ and Ca2+ ions, that can testify about the interrelation between endogenic thiamine phosphorilation and its transport through the membrane. Thiamine binding with synaptosomes is inhibited by ouabain and neurotoxins such as, latrotoxin and most significantly--with veratridin; tetrodotoxin fail to be efficient practically. In the conditions of synaptic membranes depolarisation their ability to bind thiamine is reduced and output of already uptaken with synaptosomes thiamine is observed.

The effect of inhibited duodenal motor-evacuation on the rate of protein, glucose, and lipid absorption was studied in chronic experiments in 5 polyfistulous dogs. Evacuation was inhibited by division of Treitz's ligament (a model of duodenostasis). The results of the experiments are evidence of a considerable regulatory effect of chyme evacuation rate on the value of the flow of substances from the enteral medium into the blood. The evacuation rate is in inverse proportion to the adsorption rate.

The effect of thiamine triphosphate (ThTP) and thiamine diphosphate (ThDP) on the activity of rat liver pyruvate dehydrogenase complex regulatory enzymes (kinase and phosphatase) was studied in experiments with isolated enzyme preparations. It is shown that ThDP caused a pronounced activation of pyruvate dehydrogenase phosphatase (Ka is equal to 65.0 nM). ThTP inhibits phosphatase competitively against the substrate--the phosphorylated pyruvate dehydrogenase complex. The both thiamine phosphates inhibit the pyruvate dehydrogenase kinase activity almost similarly in concentrations exceeding 10 microM. The physiological significance of the antagonistic action of ThDP and ThTP on the pyruvate dehydrogenase phosphatase activity is discussed.