RESUMO
Extracts of Gymnemy sylvestre (GS) exhibit hemorheological activity. The most pronounced effect was observed for GL extract in 25 wt % concentration, which (i) induced a decrease in the viscosity of blood and washed erythrocyte suspensions in the entire range of shear rates by a factor of 1,3 (ii) reduced the degree of deformability of red blood cells, (iii) increased the degree of osmotic resistance of erythrocytes by 21.3%, (iv) increased the intensity of fluorescence of DSM+ probe in erythrocyte suspensions by a factor of 1.5, and (v) decreased the degree of anisotropy, thus generally improving the viscoelastic properties of the erythrocyte membrane and preventing the thrombocyte aggregation. In this respect, the GS extract activity exceeded that of Tanakan.
Assuntos
Diabetes Mellitus Experimental/sangue , Eritrócitos/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Viscosidade Sanguínea/efeitos dos fármacos , Agregação Eritrocítica/efeitos dos fármacos , Deformação Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/efeitos dos fármacos , Hemorreologia , RatosRESUMO
The main function of Csk tyrosine kinases is phosphorylation of the C-terminal part of Srk tyrosine kinases as a mechanism of their downregulation. A decrease in the expression of csk gene results in the enhancement of Srk tyrosine kinase activity. In this study, cDNA containing the full coding sequence of the human leukocyte Csk tyrosine kinase gene has been cloned. The protein encoded by a a 1624-bp cDNA fragment has 99% homology to human Csk tyrosine kinase. A comparative sequence analysis of full-length cDNAs for Csk tyrosine kinase of normal lymphocytes and lymphocytes of patients with choroidal melanoma revealed a nucleotide substitution in dexon 10 of the gene, which appears to be of diagnostic significance. It has been shown that the risk of choroidal melanoma correlated with the frequency of this allele.
Assuntos
Neoplasias da Coroide/genética , Linfócitos/enzimologia , Melanoma/genética , Proteínas Tirosina Quinases/genética , Sequência de Bases , Proteína Tirosina Quinase CSK , Neoplasias da Coroide/enzimologia , Clonagem Molecular/métodos , DNA Complementar/genética , DNA Complementar/metabolismo , Humanos , Melanoma/enzimologia , Dados de Sequência Molecular , Mutação , Proteínas Tirosina Quinases/isolamento & purificação , Proteínas Tirosina Quinases/metabolismo , Quinases da Família srcRESUMO
Tyrosine kinases of Csk family play important role in the cell growth regulation and normal cell differentiation and also can participate in the process of cancer genesis as oncoproteins. The main function of these tyrosine kinases is the phosphorylation of the Src family tyrosine kinases at their carboxyl terminus, which is the basis of their activity negative regulation. The disturbance of the csk gene expression leads to the increase of the Src tyrosine kinase activity. We have cloned a full-length encoding cDNA of the tyrosine kinase csk gene of human lymphocytes. 1.6-kilobase cDNA encodes the protein, which consists of 12 exons with conserved SH2 and SH3 domains. The homology between this protein and human Csk tyrosine kinase is 99%. A full-length DNA-copy of human lymphocytes RNA can be used for the analysis of csk gene structure in normal and pathologically changed human cells.