ROLE OF SUBSTRATE ANTIHYPOXANTS IN CORRECTION OF ABNORMALITIES OF MYOELECTRICAL ACTIVITY OF GASTROINTESTINAL TRACT IN VICTIMS WITH SEVERE COMBINED TRAUMA

The abnormalities of myoelectrical activity of gastrointestinal tract were detected in 80 victims with severe combined trauma. There were observed a decrease of total electrical activity and dyscoordination of electrical activity of sections of gastrointestinal tract. An application of substrate antihypoxants should normalize the indices of myoelectrical activity of gastrointestinal tract. This approach allowed elimination of imbalance of total power between superposed (the stomach, the duodenum) and other sections of gastrointestinal tract. This would remove dyscoordination contraction of the jejunum and the ileum

Extreme iron isotope fractionation between colloids and particles of boreal and temperate organic-rich waters

Significant and systematic variations of iron isotopic composition in surface water sample fractions obtained by frontal cascade filtration and ultrafiltration have been recorded in (1) subarctic organic-rich boreal river and stream, mire, lake and soil solutions in northern taiga zone (Karelia, NW Russia) and (2) temperate river and lake waters of the southern boreal zone (Central Russia). Water samples were filtered in the field employing progressively decreasing pore size from 100 mu m to 1 kDa followed by iron isotope analysis. In all river samples, there was a gradual increase of delta Fe-57 relative to IRMM-14 with decreasing pore size, from +0.4 +/- 0.1 parts per thousand at 100 mu m up to +4.2 +/- 0.1 parts per thousand at 10 kDa fraction in the subarctic zone and from -0.024 +/- 0.2 parts per thousand at 100 mu m up to +1.2 +/- 0.2 parts per thousand at 10 kDa in the temperate zone. In the series of filtrates/ultrafiltrates of subarctic and temperate streams and rivers, the delta Fe-57 value decreases with increasing molar Fe/C-org ratio. Therefore, small-size, Fe-poor, C-rich colloids (1-10 kDa) and Low Molecular Weight (LMW) fractions of oxygenated water exhibit strong enrichment in heavy isotope whereas High Molecular Weight Fe-rich colloids (100 kDa-0.22 mu m) and particles (1-100 mu m) are isotopically lighter and closer to the continental crust Fe isotope composition. The relative enrichment of 1-10 kDa ultrafiltrates in heavy isotopes suggests that low molecular weight ligands bind Fe more strongly (Fe-O-C bonds) than Fe(III)oxy(hydr)oxides (Fe-O-Fe bonds), in accord with quantum mechanics principles. Highly positive delta Fe-57 of the LMW fraction of labile and potentially bioavailable Fe in small subarctic rivers may turn out to be a very important source of isotopically heavy Fe in the Arctic Ocean. The mechanisms involved in the production of this isotopically heavy Fe may lead this tracer to become a new indicator of environmental changes occurring in the boreal zone

EARLY ENTERAL INFUSSIONS IN COMPLEX TREATMENT OF SEVERE COMBINED CHEST TRAUMA

On the basis of study and treatment of 98 victims it was stated that the absorption of isotonic glucose electrolytes solutions in the small intestine was saved even increased in case of large hemorrhage in severe polytrauma with chest, abdominal injury and other regions trauma. An application of early enteral infusions allowed reducing of the volume of parenteral introduction solutions and facilitated to a reliable decrease of development frequency of nosocomial pneumonia of attributive lethality

Dissolved organic matter degradation by sunlight coagulates organo-mineral colloids and produces low-molecular weight fraction of metals in boreal humic waters

International audiencePhotochemical degradation of dissolved organic matter (DOM) is recognized as the major driver of CO2 emission to the atmosphere from the inland waters of high latitudes. In contrast to numerous studies of photo-induced DOM transformation, the behavior of trace element (TE) during photodegradation of boreal DOM remains virtually unknown. Towards a better understanding of concentration, size fractionation and speciation change of DOM and TE in boreal waters subjected to solar radiation, we conducted on-site photo-degradation experiments in stream and bog water collected from a pristine zone of the Northern Karelia (Russian subarctic). The removal of Fe and Al occurred only in the bog water (90% and 50% respectively, over 5 days of reaction), whereas no detectable decrease of dissolved ( fraction was preferentially enriched in Fe, Al, Ca, Mg and other divalent metals relative to Corg. The climate warming leading to water temperature rise in the boreal zone will intensify the Fe and Al hydroxide coagulation while increasing the production of LMW organic ligands and free metals and metal - organic complexes

Transformation of organo-ferric peat colloids by a heterotrophic bacterium

International audienceBacterial mineralization of allochthonous (soil) dissolved organic matter (DOM) in boreal waters governs the CO2 flux from the lakes and rivers to the atmosphere, which is one of the main factor of carbon balance in high latitudes. However, the fate of colloidal trace element (TE) during bacterial processing of DOM remains poorly constrained. We separated monoculture of Pseudomonas saponiphila from a boreal creek and allowed it to react with boreal Fe-rich peat leachate of approximate colloidal (3 kDa-0.45 μm) composition C1000Fe12Al3.3Mg2Ca3.7P1.2Mn0.1Ba0.5 in nutrient-free media. The total net decrease of Dissolved Organic Carbon (DOC) concentration over 4 day of exposure was within 5% of the initial value, whereas the low molecular weight fraction of Corg (LMW kDa) yielded a 16%-decrease due to long-term bio-uptake or coagulation. There was a relative depletion in Fe over Corg of 0.45 μm, colloidal and LMW fraction in the course of peat leachate interaction with P. saponiphila. Al, Mn, Ni, Cu, Ga, REEs, Y, U were mostly affected by bacterial presence and exhibited essentially the adsorption at the cell surface over first hours of reaction, in contrast to Fe, Ti, Zr, and Nb that showed both short-term adsorption and long-term removal by physical coagulation/coprecipitation with Fe hydroxide. The low molecular weight fraction (LMW kDa) of most TE was a factor of 2-5 less affected by microbial presence via adsorption or removal than the high molecular weight (HMW) colloidal fractions (<0.45 μm and <50 kDa). The climate change-induced acceleration of heterotrophic bacterial activity in boreal and subarctic waters may lead to preferential removal of Fe over DOC from conventionally dissolved fraction and the decrease of the proportion of LMW < 3 kDa fraction and the increase of HMW colloids. Enhanced heterotrophic mineralization of organo-ferric colloids under climate warming scenario may compensate for on-going "browning" of surface waters