Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0012739 (disseminated intravascular coagulation)
 8,673 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The impact of water quality changes in River Changjiang (formally known as the Yangtze River) on dissolved CO2 and silicate concentrations and seasonal carbon flux in the past several decades (1960s-2000) was evaluated, based on monitoring data from hydrographic gauge. It was found that dissolved CO2 and silicate in Changjiang decreased dramatically during this decades, as opposed to a marked increase in nutrient (e.g. NO3-) concentrations. Our analyses revealed that dissolved CO2 in Changjiang was over-saturated with the atmosphere CO2, and its concentration had showed a declining trend since the 1960s, despite that fluvial DIC flux had maintained stable. Analysis results also suggested that the decrease in dissolved CO2 concentration was attributed to changes on the riverine trophic level and river damming activities in the Changjiang drainage basin. Due to the economic innovation (e.g. agriculture and industry development) across the Changjiang watershed, fertilizers application and river regulations have significantly altered the original state of the river. Its ecosystem and hydrological condition have been evolving toward the "lacustrine/reservoir" autotrophic type prevailing with plankton. Accordingly, average CO2 diffusing flux to the atmosphere from the river had been reduced by three-fourth from the 1960s to 1990 s, with the flux value being down to 14.2 mol.m-2.yr-1 in the 1990 s. For a rough estimate, approximately 15.3 Mt of carbon was degassed annually into the atmosphere from the entire Changjiang drainage basin in the 1990 s.
 ...
PMID:Human impact on the historical change of CO2 degassing flux in River Changjiang. 1768 86

The stable isotopic analyses of molecular oxygen dissolved in water (delta18O(DO)) and dissolved inorganic carbon (delta13C(DIC)), supplemented with basic chemical measurements, have been carried out on a diurnal basis to better understand the dynamics of photosynthesis and respiration in freshwater systems. Our observations have been carried out in a lowland dam reservoir, the Sulejow Lake (central Poland), during the summer cyanobacterial bloom. All data obtained, isotopic, hydrochemical, and biological, show a high mutual consistency. Namely, the lowest delta18O(DO) values, obtained at 10:00 and 14:00 (16.0 and 15.5 per thousand, respectively), correspond to the highest amount of cyanobacterial cells observed (66 and 63 mg dm(-3), respectively), whereas the minimum delta13C(DIC) (-10.6 per thousand) obtained at 22:00 corresponds to the maximum content of organic matter (110 mg dm(-3)). This evidence suggests that isotopic assays of delta18O(DO) and delta13C(DIC) are a reliable tool for the quantitative study of biochemical processes in freshwater systems.
 ...
PMID:Diurnal variations in the photosynthesis-respiration activity of a cyanobacterial bloom in a freshwater dam reservoir: an isotopic study. 1856 88

The study of the oligosaccharides extracted from Tephrosia purpurea seeds was undertaken using the instant controlled pressure drop (DIC) as a pre-treatment prior to conventional solvent extraction. This DIC procedure provided structural modification in terms of expansion, higher porosity and improvement of specific surface area; diffusion of solvent inside such seeds and availability of oligosaccharides increase notably. In this paper, we investigated and quantified the impact of the different DIC operative parameters on the yields of ciceritol and stachyose extracted from T. purpurea seeds. The treatment could be optimized with a steam pressure (P) (P=0.2 MPa), initial water content (W) (W=30% dry basis (DB)) and thermal treatment time (t) (t=30s). By applying DIC treatment in these conditions, the classic process of extraction was intensified in both aspects of yields (145% of ciceritol and 185% of stachyose), and kinetics (1h of extraction time instead of 4h for conventional process). The scanning electron microscopy micrographs provided evident modifications of structure of seeds due to the DIC treatment.
 ...
PMID:Effect of instant controlled pressure drop treatments on the oligosaccharides extractability and microstructure of Tephrosia purpurea seeds. 1899 89

We analyzed the major elements and stable isotopes of oxygen, hydrogen, and carbon (dissolved inorganic carbon: DIC) in various types of bottled water (domestic and foreign) commercially available in South Korea to classify the water types and to identify their origins. Only marine waters and some sparkling waters could be discriminated by their physicochemical compositions. Oxygen and hydrogen isotopes made marine waters more distinguishable from other water types. The determination of the carbon isotope composition of DIC was clearly useful for distinguishing between naturally and artificially sparkling waters. In addition, statistical analysis also appeared to aid in the discrimination of bottled water types. Our results indicate that a method that combines chemical and stable isotope composition analysis with statistical analysis is the most useful for discriminating water types and characterizing the origins of bottled water.
 ...
PMID:Characterizing the origins of bottled water on the South Korean market using chemical and isotopic compositions. 1908 25

There is a great potential to assimilate CO(2) and produce bio-energy from cellular component by utilizing carbon fixation of photosynthetic microorganisms. Two different types of photosynthetic microorganisms were used in the present study. The strain Thermosynechococcus sp. CL-1 (TCL-1) was previously isolated from a hot spring while Nannochloropsis sp.Oculta (NAO) from sea water. Two types of inorganic carbon were used (gaseous CO(2) and dissolved inorganic carbon, DIC) with nitrate as N source under different temperature conditions. The Monod model was used to relate its growth rate and DIC concentration. Additionally, lipid and carbohydrate of cell component, which can be used as bio-energy precursors, as function of CO(2) and DIC concentrations is quantified. The growth rate of TCL-1 decreased as CO(2) concentrations increased from 10% to 40% due to low pH inhibition with the maximum value 2.7 d(-1) at 10% CO(2). As for NAO, the maximum growth rate of about 1.6 d(-1) was obtained at 5% and 8% CO(2) (pH between 5.5 and 7 at 30 degrees C). Regarding the cultivation of TCL-1 under various DIC concentrations, the maximum growth rate of TCL-1 was 3.5 d(-1) at the initial DIC 94.3 mM, pH 9.5 and 50 degrees C. The carbohydrate content of TCL-1 increased from 2.1% to 33% as DIC concentration increased from 4.7 to 94.3 mM. However, the 33% carbohydrate content at 94.3 mM DIC was much less than 61% at 10% CO(2). That may be due to the fact that the cultivation at 94.3 mM DIC can not supply adequate amounts of DIC to produce carbohydrate under N-limiting conditions. Conversely, enough amounts of DIC supplied from washing flue gas for cultivating TCL-1 would provide a higher performance of carbon bio-fixation and carbohydrate production.
 ...
PMID:Carbon bio-fixation by photosynthesis of Thermosynechococcus sp. CL-1 and Nannochloropsis oculta. 1916 7

Major ion chemistry and dissolved inorganic carbon system (DIC, mainly HCO3(-) and gaseous CO2) in the Luodingjiang River, a mountainous tributary of the Zhujiang (Pearl River), China, were examined based on a seasonal and spatial sampling scheme in 2005. The diverse distribution of lithology and anthropogenic impacts in the river basin provided the basic idea to assess the effects of lithology vs. human activities on water chemistry and carbon biogeochemistry in river systems. Major ions showed great spatial variations, with higher concentrations of total dissolved solids (TDS) and DIC in the regions with carbonate rocks and clastic sedimentary rocks, while lower in the regions with metamorphic sandstones and schists as well as granites. pCO2 at all sampling sites was oversaturated in June, ranging with a factor from 1.6 to 18.8 of the atmospheric concentration, reflecting the enhanced contribution from baseflow and interflow influx as well as in situ oxidation of organic matter. However, in April and December, undersaturated pCO2 was found in some shallow, clean rivers in the upstream regions. delta13C of DIC has a narrow range from -9.07 to -13.59 per thousand, which was more depleted in the regions with metamorphic rocks and granites than in the carbonate regions. Seasonally, it was slightly more depleted in the dry season (December) than in the wet season (June). The results suggested that lithological variability had a dominant control on spatial variations of water chemistry and carbon geochemistry in river systems. Besides, anthropogenic activities, such as agricultural and urban activities and in-stream damming, as well as river physical properties, such as water depth and transparency, also indicated their impacts. The seasonal variations likely reflected the changes of hydrological regime, as well as metabolic processes in the river.
 ...
PMID:Major ion chemistry and dissolved inorganic carbon cycling in a human-disturbed mountainous river (the Luodingjiang River) of the Zhujiang (Pearl River), China. 1918 5

In this work the application of two levels of N fertilizer (NH(4)NO(3)) dissolved in water or olive oil mill wastewater (OOMW) diluted 10 or 20 times in water, has been studied in relation to the properties of two soils (Loam and Silt-Clay-Loam). Also, the effect of irrigation water bubbled with CO(2) (Dissolved Inorganic Carbon, DIC) was studied. Nitrate N, ammonium N, total N, organic C (OC), and CaCO(3) contents were determined in the soil as well as pH, electrical conductivity (EC), oxidation-reduction potential (ORP), and absorbance at 250 and 360 nm. Our data provide evidence that inorganic-N fertilizer dissolved in OOMW significantly reduced the emission of nitrates from soils for two months, increasing OC values. Moreover, OOMW significantly lowered the ORP. The irrigation with DIC also increased soil OC. Thus, the application of inorganic-N fertilizers dissolved in OOMW diluted with water on soils and the irrigation with water bubbled with CO(2) could reduce the environmental impact of OOMW, nitrates, and CO(2).
 ...
PMID:Olive oil mill wastewater for soil nitrogen and carbon conservation. 1933 3

Polycarbonates are promising biomaterials due to their biocompatibility, degradability and low toxicity. In this study, a series of COOH-functionalized polycarbonates was synthesized via an organocatalytic ring opening polymerization pathway under mild conditions. The polymers displayed a range of molecular weights (M(w): 3.1, 5.5 and 9.7 kDa) and were very narrowly distributed (polydispersity index: 1.07, 1.07 and 1.15 respectively). Aliphatic amines with different chain lengths (triethylenetetramine, tetraethylenepentamine or pentaethylenehexamine) were then conjugated onto the polycarbonate backbone using DIC/NHS chemistry. These amine-functionalized polycarbonates could form nanoparticles upon simple dissolution in water and had CMC values ranging from 22 to 45 mg/L. It was found that a longer amine chain resulted in greater buffering capacity, more positive zeta potential and smaller hydrodynamic size of the polymeric nanoparticles. Results from gel retardation assays indicated that the polymers were able to condense DNA. In-vitro studies further demonstrated that selected amine-functionalized polycarbonates could mediate efficient luciferase expression in HEK293, HepG2 and 4T1 cell lines at levels that were comparable, or even superior, to the polyethylenimine (PEI) standard. Importantly, minimal cytotoxicty was induced in the cells. These functional polycarbonates therefore have the potential to be a useful non-viral vector for gene therapy.
 ...
PMID:Functional polycarbonates and their self-assemblies as promising non-viral vectors. 1947 Mar 98

The effects of typical organic pollutants (ethanol, acetone, ON, OP) on pH and marine carbon dioxide system were investigated in laboratory simulated experiments. The results indicated that the growth of biological carbon fixed system was promoted by ethanol and acetone of low concentration (< 0.5 mmol x L(-1)) (t = 7 d). So pH increased while DIC, HCO3(-) and p(CO2) significantly decreased compared to the controls (p <0.01). The concentrations of ethanol and acetone which resulted in the maximum decrease of carbon dioxide parameters were 0.25 mmol x L(-1) and 0.1 mmol x L(-1), respectively. When the infusion of organic pollutants were higher than the "critical concentration", the carbon dioxide parameters increased and pH decreased compared to the controls with the decrease of carbon fixation strength of alga. As for ON and OP groups, when they were in the range of experimental concentration, decreasing trends of inorganic carbon in sea water were always found. The concentration changes of DIC (DeltaDIC) under the press of the four typical organic pollutants were significantly negatively correlated with the changes of dry weight of alga (p < 0.01 or p < 0.05) and the coefficient parameters were -0.902, -0.945, -0.898 and -0.918, respectively (t = 7 d). The main controlling factor to the variation of carbon dioxided system was the adaption of biological carbon fixed system to different concentration and kind of organic pollutants.
 ...
PMID:[Effects of typical organic pollutants on marine dioxide carbon system in simulated experiments]. 1955 94

N-terminal modification of peptides by unnatural amino acids significantly affects their enzymatic stability, conformational properties and biological activity. Application of N-amidino-amino acids, positively charged under physiological conditions, can change peptide conformation and its affinity to the corresponding receptor. In this article, we describe synthesis of short peptides, containing a new building block-N-amidino-pyroglutamic acid. Although direct guanidinylation of pyroglutamic acid and oxidation of N-amidino-proline using RuO(4) did not produce positive results, N-amidino-Glp-Phe-OH was synthesized on Wang polymer by cyclization of alpha-guanidinoglutaric acid residue. In the course of synthesis, it was found that literature procedure of selective Boc deprotection using TMSOTf/TEA reagent is accompanied by concomitant side reaction of triethylamine alkylation by polymer linker fragment. It should be mentioned that independently from cyclization time and coupling agent (DIC or HCTU), the lactam formation was incomplete. Separation of the cyclic product from the linear precursor was achieved by HPLC in ammonium formate buffer at pH 6. HPLC analysis showed N-amidino-Glp-Phe-OH stability at acidic and physiological pH and fast ring opening in water solution at pH 9. The suggested method of N-amidino-Glp residue formation can be applied in the case of short peptide chains, whereas synthesis of longer ones will require fragment condensation approach.
 ...
PMID:Incorporation of N-amidino-pyroglutamic acid into peptides using intramolecular cyclization of alpha-guanidinoglutaric acid. 1973 27


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>