258 research outputs found
The study of organogel formation with cyclo(leucyl-leucine) by the AFM method
This work was supported by the ministry of education and science of russian federation [grant №14.y26.31.0019
Influence of quantity of amino-acid residues in the oligopeptides based on glycine on their self-organization in films
Electrocatalytic Oxidation of Cysteine and Cystine at a Carbon-Paste Electrode Modified with Ruthenium(IV) Oxide
The electrocatalytic activity of ruthenium(IV) oxide incorporated into a carbon-paste electrode was studied in the oxidation of cysteine and cystine. The oxidation potentials of the amino acids decreased and the current peaks of their oxidation increased at a modified electrode as compared to an unmodified one. Procedures for the voltammetric determination of cysteine and cystine with the use of electrodes chemically modified with ruthenium(IV) oxide were proposed
Post- Anesthetic rehabilitation periods and anesthesia dosage for laparoscopic cholecystectomy: Relationship to the total oxidative capacity of liver
Analysis of the results of pharmacological phenotyping using antipyrine test prior to providing anesthesia for laparoscopic cholecystectomy showed that trimeperidine (promedol) dosing with allowance for the total oxidative capacity of liver and the patient mass allows the periods of post- Anesthetic rehabilitation to be controlled. Clear algorithm of trimeperidine dosing based on established indices of the total oxidative capacity of liver and is yet nor developed because of restricted sampling set. The obtained results show expediency of using and studying antipyrine test as a simple, cheap, and informative method of individual anesthesia dosing for increasing the adequacy of general anesthesia
Electrocatalytic oxidation and flow-injection determination of sulfur-containing amino acids at graphite electrodes modified with a ruthenium hexacyanoferrate film
The electrochemical behavior of sulfur-containing amino acids (cysteine, cystine, and methionine) at graphite electrodes modified with a ruthenium(III) hexacyanoferrate(II) film was studied. Glassy carbon and carbon paste were used as graphite materials. The electrocatalytic oxidation of amino acids at a modified electrode resulted in a decrease in the oxidation potentials of amino acids and an increase in the currents of their oxidation peaks as compared to those observed at an unmodified electrode. The voltammetric characteristics and hydrodynamic conditions for detecting the maximum catalytic current were found. A procedure is proposed for the electrocatalytic determination of cysteine, cystine, and methionine at a carbon-paste electrode modified with an inorganic film of ruthenium(III) hexacyanoferrate(II) under the conditions of flow-injection analysis
Surface morphology and electrocatalytic properties of nickel nanoparticles formed in track pores
© 2016, Pleiades Publishing, Ltd.Structures, each of which is composed of a conducting substrate with a protective dielectric layer containing an array of equal-sized pores formed under the action of high-energy ions and chemical etching, are created. The created pores are electrochemically filled with nickel nanoparticles. With atomic-force microscopy (AFM), it is established that Ni nanoparticles are generated exclusively within ion tracks without film formation on the surface of a silicon-dioxide layer. Histograms illustrating the nanoparticle-diameter distribution are constructed, and areas of the nickel nanoparticles are calculated. The electrochemical and electrocatalytic properties of Ni nanoparticles inherent to ethanol-oxidation reactions are investigated. The catalytic activity per unit area of the nanocatalyst is estimated using voltammograms, AFM data, and histograms characterizing the particle size distribution
Comparative analysis of methanogenic communities in different laboratory-scale anaerobic digesters
© 2016 Ayrat M. Ziganshin et al.Comparative analysis of methanogenic archaea compositions and dynamics in 11 laboratory-scale continuous stirred tank reactors fed with different agricultural materials (chicken manure, cattle manure, maize straw, maize silage, distillers grains, and Jatropha press cake) was carried out by analysis of the methyl coenzyme-M reductase -subunit (mcrA) gene. Various taxa within Methanomicrobiales, Methanobacteriaceae, Methanosarcinaceae, Methanosaetaceae, and Methanomassiliicoccales were detected in the biogas reactors but in different proportions depending on the substrate type utilized as well as various process parameters. Improved coverage and higher taxonomic resolution of methanogens were obtained compared to a previous 16S rRNA gene based study of the same reactors. Some members of the genus Methanoculleus positively correlated with the relative methane content, whereas opposite correlations were found for Methanobacterium. Specific biogas production was found to be significantly correlating with Methanosarcinaceae. Statistical analysis also disclosed that some members of the genus Methanoculleus positively correlated with the ammonia level, whereas the prevalence of Methanocorpusculum, Methanobacterium, and Methanosaeta was negatively correlated with this parameter. These results suggest that the application of methanogenic archaea adapted to specific feedstock might enhance the anaerobic digestion of such waste materials in full-scale biogas reactors
Amperometric cholinesterase biosensors with carbon paste electrodes modified with cobalt phthalocyanine
Biosensors based on a carbon paste electrode with immobilized cholinesterase and cobalt(II) phthalocyanine as a mediator are studied. Electrochemical characteristics of the biosensors are investigated in relation to the carbon paste composition, the enzyme and mediator immobilization procedures, nature of the protective film and procedure of its application, and also storage conditions of the electrodes. A method is suggested for fabricating a cholinesterase biosensor with cobalt(II) phthalocyanine mediator, providing the maximum electrocatalytic response in electrooxidation of butyrylthiocholine iodide (substrate for cholinesterase)
Synthesis and study of inorganic pigment properties on the basis of dead chrome catalyst
Generation of unprocessed wastes of industrial production is the key part of multi-factor negative impact on environment. The technologies of catching and neutralization of discharges and wastes have been developed extremely slow, as a result of it, the level of utilization remains to be low (only half of them is reused in production). All these concern in full measure chemical industry and adjacent branches of production - coal industry, mining, metallurgy, energy. In particular, only in chemical industry it has been calculated about 800 names of wastes. Major part of wastes is deleterious and hazardous to biosphere, processing toxicity, chemical, biological activities, corrosiveness, inflammability and explosibility. On the other hand - industrial wastes contain valuable elements, in particular different metals, the reserves of them are exhaustible. Waste burial is unpractical from the point of view of stability of functioning of industrial complex on the whole. The industrial wastes are often multi-component mixtures of substances of heterogeneous chemical composition, having different physical and chemical properties. The processes of interaction between the components and the background objects and by-product assimilation bring a considerable uncertainty in chemical composition and material constitution of industrial wastes. The technologies of waste recycling to receive the products, specifically inorganic pigments, involve the complex of methods of processing with the use of different modifiers to obtain the needed complex of physical and chemical properties defining the functional characteristics of the target product
Angiogenesis-Related Factors in Early Pregnancy Loss
The habitual loss of early pregnancy is one of the major problems of obstetrics nowadays, provided that the cause of more than 50% of all early pregnancy losses is unknown. Adequate angiogenesis is one of the main indicators of proper formation of placental system, making the basis of fetal life support. The objective description of angiogenesis in physiological development of pregnancy and in pathological conditions is complicated by the difficulties in obtaining and characterizing placental tissue in early pregnancy. Thus, angiogenesis‐related factors are promising indicators to characterize angiogenesis in pregnancy. This chapter draws attention to alteration in angiogenesis‐related factors in peripheral blood of patients with habitual early pregnancy losses. Investigation of factors (vascular endothelial growth factor (VEGF), sFlt‐1, sKDR, metalloproteinase (MMP)‐2, MMP‐9, tissue inhibitor (TIMP)‐1, TIMP‐2 and placental growth factor (PLGF)), which specifically and nonspecifically regulate angiogenesis in pregnancy, was performed in the most significant terms for placentogenesis: 6 weeks, 7–8 weeks and 11–14 weeks of pregnancy. It was found that in a missed abortion there was a significant imbalance of angiogenesis‐related factors compared with normal pregnancy. These results reflect a disturbance of angiogenesis in a missed abortion and point to the importance of the studied factors in the pathogenesis of early pregnancy losses
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