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Janaína A Couto Karina LA Saraiva Cleiton D Barros Daniel P Udrisar Christina A Peixoto Juliany SB César Vieira Maria C Lima Suely L Galdino Ivan R Pitta Maria I Wanderley 《Reproductive biology and endocrinology : RB&E》2010,8(1):13
Background
The present study was designed to examine the effect of chronic treatment with rosiglitazone - thiazolidinedione used in the treatment of type 2 diabetes mellitus for its insulin sensitizing effects - on the Leydig cell steroidogenic capacity and expression of the steroidogenic acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc) in normal adult rats. 相似文献74.
75.
For the first time, from the surface of the dikaryotic mycelium of the xylotrophic basidiomycete Grifola frondosa 0917 a lectin has been isolated with a molecular mass of 68 +/- 1 kDa, consisting of two subunits of 33-34 kDa each. The lectin is a hydrophilic glycoprotein with the protein : glycan ratio of 3 : 1. It exhibits high affinity to native rabbit erythrocytes and to human erythrocytes of the 0 blood group, but not to trypsin-treated ones. The hemagglutination (HA) caused by lectin was not blocked by any of the 25 tested mono-, di-, and amino sugars; it was also not blocked by some of glyco derivatives. Only 13.9 microg/ml of the homogeneous preparation of a polysaccharide, a linear D-rhamnan with the structure of the repetitive component --> 2)-beta-D-Rhap-(1 --> 3)-alpha-D-Rhap-(1 --> 3)-alpha-D-Rhap-(1 --> 2)-alpha-D-Rhap-(1 --> 2)-alpha-D-Rhap-(1 --> blocked hemagglutination completely. The analysis of the amino acid composition of the lectin showed the greatest percentage of amino acids with positively charged R groups, arginine, lysine, and histidine, as well as the complete absence of sulfur-containing amino acids, cysteine, and methionine. D-glucose and D-glucosamine were detected in the carbohydrate part. 相似文献
76.
K. E. Yakovleva S. A. Kurzeev E. V. Stepanova T. V. Fedorova B. A. Kuznetsov O. V. Koroleva 《Applied Biochemistry and Microbiology》2007,43(6):661-668
Phenolic acids and flavonoids were characterized by cyclic voltammetry and total antioxidant activity in the reaction with the ABTS cation radical. Anode peak voltages (Eap) and their pH dependences were determined for the studied phenolic acids and flavonoids. The Eap and Trolox equivalent antioxidant capacity (TEAC) values were found to correlate for polyphenols, which react with the ABTS cation radical in two steps. Correlation between the half-wave potential (E1/2) and TEAC was determined for electrochemically irreversible compounds. Mechanisms of the reaction of phenolics on the electrode involving one-and two-electron oxidation are proposed. 相似文献
77.
Iakovleva KE Kurzeev SA Stepanova EV Fedorova TV Kuznetsov BA Koroleva OV 《Prikladnaia biokhimiia i mikrobiologiia》2007,43(6):730-739
Phenolic acids and flavonoids were characterized by cyclic voltammetry and total antioxidant activity in the reaction with the ABTS cation radical. Anode peak voltages (Eap) and their pH dependences were determined for the studied phenolic acids and flavonoids. The Eap and Trolox equivalent antioxidant capacity (TEAC) values were found to correlate for polyphenols, which react with the ABTS cation radical in two steps. Correlation between the half-wave potential (Ep/2) and TEAC was determined for electrochemically irreversible compounds. Mechanisms of the reaction of phenolics on the electrode involving one- and two-electron oxidation are proposed. 相似文献
78.
R Gon?alves LA Szmuchrowski LS Prado BP Couto JCQ Machado VO Damasceno JA Lamounier 《Biology of sport / Institute of Sport》2015,32(3):255-260
The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. 相似文献
79.
Kiselev O. I. Vasin A. V. Shevyryova M. P. Deeva E. G. Sivak K. V. Egorov V. V. Tsvetkov V. B. Egorov A. Yu. Romanovskaya-Romanko E. A. Stepanova L. A. Komissarov A. B. Tsybalova L. M. Ignatjev G. M. 《Molecular Biology》2015,49(4):480-493
Molecular Biology - Ebola hemorrhagic fever (EHF) epidemic currently ongoing in West Africa is not the first among numerous epidemics in the continent. Yet it seems to be the worst EHF epidemic... 相似文献
80.
Lada V. Stepanova Gennady L. Burygin Valentina E. Nikitina Olga M. Tsivileva 《World journal of microbiology & biotechnology》2011,27(7):1579-1585
Both quantitative and qualitative estimations of the basidiomycete Grifola frondosa lectin binding to the specific and non-specific polyclonal rabbit antibodies were attempted. The lectin complexation with
homological antibodies was shown to be characterized by greater binding constants as compared to non-homological antibodies.
Therewith the values of changes in standard free energy ∆G
0 displaying a strength of both complexes were essentially the same. The data obtained testify to universality of biospecific
reactions “antigen–antibody” and “lectin–carbohydrate” at a molecular level, and could give new insight into the phenomenon
of these biospecific interactions. The actual specificity in the above bio-recognition processes could differ from the results
of in vitro assays using lectins, and, therefore, should be interpreted carefully when concluding on the lectins behaviour
in living systems. 相似文献