J Colloid Interface Sci
July 1999
The data obtained show that at pH 7 copper(II) ions are adsorbed on a SiO2 surface as polymeric species of hydroxide nature. The structure of these species is similar to that of the bulk amorphous copper hydroxide. The amorphous state of supported Cu(OH)2 is caused by a small (ca.
View Article and Find Full Text PDFComposition and structure of the surface compounds formed after interaction between Cu(OH)2 supported on aerosil and bpy, py, PhOH, and H2O2 are studied. The EXAFS and electron spectroscopy methods show the main part of copper ions to remain in a hydroxide surrounding, whose structure does not change practically and does not depend on the nature of the extra ligands used. The colloidal Cu(OH)2 stabilized by starch is found to reveal the same properties as the supported one, but differs by greater sizes of hydroxide particles.
View Article and Find Full Text PDFThe effect of chronic administration of beta-guanidinopropionic acid (GPA) on the protein profiling, energy metabolism and right ventricular (RV) function was studied in the rat heart during the weaning and adolescence period. GPA was given in tap water (1-1.5%) using pair drink controls.
View Article and Find Full Text PDFTo investigate how growth hormone (GH)-releasing peptide (GHRP) and GH-releasing hormone (GHRH) interact in patients with short stature, we examined the acute effects of GHRH1-29NH2, GHRP-2, and the combination of GHRH1-29NH2 and GHRP-2 on GH release in children with GH insufficiency ([GHI] group A) and idiopathic short stature ([ISS] group B). Ten children with GHI (aged 11.8 +/- 1.
View Article and Find Full Text PDFTreatment of perfused rat hearts with 0.5 mM iodoacetamide (IAAm) for 15 min at different workloads resulting in a nearly complete inhibition of creatine kinase (CK, 99%) was followed by a rapid decline of the phosphocreatine (PCr) level (30%) and a 2-fold increase of the P(i) level which then stabilized. Conversely, the ATP content started to drop monotonously at the beginning of the IAAm washout and reached 30% 90 min after the IAAm removal under medium load.
View Article and Find Full Text PDFProbl Endokrinol (Mosk)
June 1991
The effect of monomeric (glycosylated and unglycosylated) and dimeric form of porcine prolactin on change of the blood levels of triglycerides (TG) and cholesterol in lipoproteins (LP) of different density and the activity of the main enzymes of plasmatic and liver lipid metabolism were studied under the conditions of experimental hyperprolactinemia in rabbits. It was shown to be accompanied by dyslipoproteinemia, characterized by a stable rise of TG in LP of very low, high and low density as well as by a rise of cholesterol concentration in VLDL and its decrease in HDL. Such changes in LP showed correlation with lowered activity of lipoprotein lipase, triglyceride lipase of the liver and plasmatic postheparin lipolytic activity.
View Article and Find Full Text PDFIsolated perfused guinea pig hearts were arrested by a high K+ cardioplegic solution containing (PG group) or lacking (control group) 10 mM phosphocreatine + 15 mM glutamate. Total normothermic ischemia lasted 45 min followed by 30 min reperfusion. Mitochondrial respiration in the absence and presence of different concentrations of ADP and creatine was studied in biopsy samples (6-8 mg) after saponin treatment.
View Article and Find Full Text PDFProbl Endokrinol (Mosk)
July 1989
A comparative analysis of immunological properties of previously isolated and structurally characterized glycosylated porcine prolactin was performed. Immunoelectrophoresis with antisera to nonmodified and glycolysated hormones revealed no qualitative differences in their immunological properties. Two radioimmunoassay systems for glycosylated and nonglycosylated prolactin were developed on the basis of these antisera.
View Article and Find Full Text PDFHuman somatotropin hormono (STH), produced by means of gene engineering in the complex program "Human growth hormone", managed by the Academy of Sciences of the USSR, Ministry of Medical and Biological Industry of the USSR and Ministry of Public Health of the USSR, was shown to be similar in its physico-chemical properties to the main isoform of highly purified STH, isolated from human hypophysis. As distinct from the hypophyseal STH (STHhyp) containing minor isoforms of the hormone, the preparation of biosynthetic STH (des-Phe1-STH; STHbio) proved to be homogeneous. Studies of biological properties showed that STHbio exhibited high, similar to STHhyp, immunological, growth-stimulating and insulin-like activities as well as it possessed the lipotropic effect in vivo.
View Article and Find Full Text PDFAfter prolonged ischemia followed by reperfusion of the isolated rat heart, irreversible heart failure is associated with creatine kinase leakage from the cells. The possible implications of MM creatine kinase leakage from myofibrillar compartments on the contractile properties of ventricular muscle have been studied in control versus ischemic hearts. Total creatine kinase activity decreased in ischemic cells while creatine kinase and ATPase activities were not modified in isolated myofibrils.
View Article and Find Full Text PDFSkinned rat papillary muscles and purified preparations of rat cardiac myofibrils were used to study the nature of the interaction of creatine kinase with cardiac myofibrils. High activity of creatine kinase (2 IU/mg protein in fibers and 0.9 IU/mg in purified myofibrils) was due mostly to reversibly bound enzyme.
View Article and Find Full Text PDFRat heart myofibrils were isolated and purified in three different media: sucrose medium; EGTA medium; EGTA+ATP medium. All preparations were characterized by similar Ca2+-sensitive ATPase activities and were practically free of mitochondrial and sarcolemmal contaminations. However, they contained different amounts of creatine kinase.
View Article and Find Full Text PDFBiull Vsesoiuznogo Kardiol Nauchn Tsentra AMN SSSR
March 1988
The state of myofibril creatinkinase and contractile properties of chemically skinned myocardial fibers of rat after 70-90 min ischemia and 15-30 min reperfusion was studied. In spite of sharp fall in the total creatinkinase activity in the tissue, the enzyme activity in myofibrils does not change greatly. Ischemia does not change the functional abilities of myofibril creatinkinase as well as characteristics of Ca-activated contraction of skinned fibers.
View Article and Find Full Text PDFThe protein hormone prolactin was isolated from sea whale hypophysis and its amino acid sequence was partially characterized. The hormone was hydrolyzed by BrCN and trypsin, the products of hydrolysis were separated and purified by gel filtration on Sephadex G-50, G-100 and G-25, by ion-exchange chromatography on CM-cellulose and on Dowex 50 x 8 and by partition paper chromatography. The structure of the obtained peptides was determined by the Edman method and by carboxypeptidase A hydrolysis.
View Article and Find Full Text PDFSynthesis of neuraminidase activity in an affinity column with an inhibitor para-amino-phenyloxamine acid (PAPOA), immobilized on sepharose via tripeptide "spacer" (glycyl-glycyl-tyrosine) is described as well as the conditions of PAPOA synthesis. The column has been tested for isolation of neuraminidase types N1 and N2 from various influenza virus strains. The strain specificity of the action of the column in neuraminidase isolation was demonstrated.
View Article and Find Full Text PDFThe maximal content of mitochondrial isoenzyme of creatine kinase (CK) in rat heart mitochondria does not exceed 12.5 moles per mole of ATP-ADP translocase. This value was obtained by titration of mitochondrial CK activity in aged mitochondria by 5,5'-dithiobis-(2-nitrobenzoate) (DTNB) and 2,4-dinitrofluorobenzene (DNFB) and by a more complex and accurate method.
View Article and Find Full Text PDFThe method of penetrating ions was used to measure the membrane potential and to study the creatine phosphokinase reaction in rat heart mitochondria. The concentration of adenine nucleotides in the intermembrane space at different levels of the membrane potential was estimated. The role of the diffusional layer adjacent to the inner membrane of heart mitochondria for coupling of the creatine phosphokinase reaction with oxidative phosphorylation is discussed.
View Article and Find Full Text PDFThe corticotropins from two species of whales, e. g. seiwhale (Balaenoptera borealis) and finwhale (Balaenoptera physalus) were subjected to hydrolysis by trypsin, chymotrypsin and pepsin.
View Article and Find Full Text PDFIn the primary structure of bovine prolactin a hydrophobic fragment 79-88 of the peptide chain was found, which participated in a maintenance of conformation of the hormone molecule in a solution due to hydrophobic interactions. The fragment contained about 50% of leucine residues, which are currently considered as important in determination of three-dimensional structure and biological functions of protein (6).
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