Navegando por Palavras-chave "HEPARAN SULFATE"
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- ItemSomente MetadadadosAPPEARANCE and FATE of A BETA-GALACTANASE, ALPHA,BETA-GALACTOSIDASES, HEPARAN-SULFATE and CHONDROITIN SULFATE DEGRADING ENZYMES DURING DEVELOPMENT of the MOLLUSK POMACEA SP(Elsevier B.V., 1994-08-18) Oliveira, F. W.; Chavante, S. F.; Santos, E. A.; Dietrich, C. P.; Nader, H. B.; Universidade Federal de São Paulo (UNIFESP); UNIV FED RIO GRANDE NORTEThe characterization and properties of a beta-galactanase and alpha- and beta-galactosidases as well as heparan sulfate and chondroitin sulfate degrading enzymes which appear during the 15 days of the embryonic development of the mollusc Pomacea sp. is reported. the beta-galactanase, which appears around day 7 of development, was separated from alpha- and beta-galactosidase which emerge at day 1 and 4 after oviposition, respectively. the galactanase seems to be responsible for the degradation of an acidic beta-galactan (which is also synthesized by the eggs around day 5) to galactose and di- and tri-galactosides. Heparan sulfate appears around day 10 of development together with a heparan sulfate endoglucuronidase responsible for the degradation of its N-acetylated region. An alpha-N-acetylglucosaminidase and a beta-glucuronidase which act upon the N-acetylated fragments formed from heparan sulfate emerge around day 4 of development. Chondroitin sulfate and a chondroitin sulfate sulfatase emerge around day 9 of development whereas a beta-N-acetylgalactosaminidase and the beta beta-galactan, heparan and chondroitin sulfate, respectively. the possible role of these elements in the migration of mesenchymal cells, in the processes of cell-cell recognition and control of cell growth is discussed.
- ItemSomente MetadadadosEFFECT of DIFFERENT GLYCOSAMINOGLYCANS in A GUINEA-PIG CAROTID-ARTERY THROMBOSIS MODEL(Elsevier B.V., 1994-09-15) Mattar, L.; Maffei, FHA; Nader, H. B.; Dietrich, C. P.; Curi, P. R.; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)Heparin is the most frequently used drug for the prevention and treatment of thrombosis. Its use, however, is restricted by its side-effects. To study the efficacy of other glycosaminoglycans that could substitute heparin in the management of arterial thrombosis, 60 guinea-pigs were randomly allocated into 6 groups: G1= control, G2= heparin (150 IU/kg), G3= heparan sulfate from beef pancreas (2.5 mg/kg), G4= heparan sulfate from beef lung (2.5 mg/kg), G5= N-acetylated heparan from beef pancreas, G6= dermatan sulfate from beef intestine (2.5 mg/kg). Ten minutes after intravenous injection of the drugs, thrombosis was induced by the injection of a 50% glucose solution into a segment of the right carotid artery isolated between 2 thread loops during 10 minutes. Three hours later the artery was re-exposed and if a thrombus was present it was measured, withdrawn and weighed. Thrombin time and activated partial thromboplastin time were measured in all animals. Thrombus developed in 90% of the animals in the control group, 0% in G2 and G3, 62.5% in G4, 87.5% in G5 and G6. Only in the animals treated with heparin the coagulation tests were prolonged. in conclusion, in the used dose only the heparan sulfate from beef pancreas presented an antithrombotic effect similar to heparin in this experimental model.
- ItemSomente MetadadadosGLYCOSAMINOGLYCAN STRUCTURE AND CONTENT DIFFER ACCORDING TO THE ORIGINS OF HUMAN TUMORS(Assoc Bras Divulg Cientifica, 1994-09-01) Jeronimo, Selma Maria Bezerra [UNIFESP]; Sales, A. O.; Fernandes, M. Z.; Melo, F. P.; Sampaio, Lucia de Oliveira [UNIFESP]; Dietrich, Carl Peter [UNIFESP]; Nader, Helena Bonciani [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); UNIV FED RIO GRANDE NORTEThe glycosaminoglycans of the tumor mass and from the urine of patients with a nephroblastoma of embryonic origin (Wilms' tumor) and hypernephroma were analyzed. The urine of patients with Wilms' tumors prior to treatment, and two patients with metastasis contained high levels of hyaluronic acid (2-5 mg/l of urine) when compared to patients after surgery or chemotherapy where the content of hyaluronic acid was less than 0.1 mg/l. Urine of patients with hypernephroma and normal individuals contained even smaller amounts of hyaluronic acid. Normal kidneys contain mainly dermatan sulfate and heparan sulfate, while the hypernephroma and Wilms' tumor contain substantial amounts of chondroitin sulfate. The amount of glycosaminoglycans isolated from Wilms' tumor and hypernephroma were 10 times and 3 times, respectively, greater than normal kidneys. The amounts of hyaluronic acid in Wilms' tumor varied from 56 to 73% whereas normal kidneys contained about 13%. Chondroitin sulfate was also increased in Wilms' tumor and hypernephroma. It corresponded to 11% and 42%, respectively, of the total glycosaminoglycans. These and other findings indicate that the glycosaminoglycans of Wilms' tumors resemble those present during embryonic development of normal tissues whereas those in hypernephroma are typical of other carcinomas of different origins.
- ItemSomente MetadadadosMITOGENIC ACTIVITY of ACIDIC FIBROBLAST GROWTH-FACTOR IS ENHANCED BY HIGHLY SULFATED OLIGOSACCHARIDES DERIVED FROM HEPARIN and HEPARAN-SULFATE(Kluwer Academic Publ, 1993-07-21) Gambarini, A. G.; Miyamoto, C. A.; Lima, G. A.; Nader, H. B.; Dietrich, C. P.; Universidade Federal de São Paulo (UNIFESP)The mitogenic activity of acidic fibroblast growth factor (aFGF) is potentiated by the highly sulfated hexasaccharide [IdoUA,2S-GlcNS,6S]2-[GlcUA-GlcNS,6S] the structural repetitive unit of lung heparin chains. On a mass basis, the effect of both heparin and oligosaccharide are equivalent whereas on a molar basis, heparin, which contains about seven hexasaccharide repeats, is more efficient. On the other hand, a pentasulfated tetrasaccharide or di- and tri-sulfated disaccharides are much less effective in potentiating aFGF activity than the hexasaccharide. If the growth factor is pre-incubated with the hexasaccharide at pH 7.2 and then exposed to pH 3.5 the 306/345 nm fluorescence ratio is similar to that of native aFGF indicating that the oligosaccharide stabilizes a native conformation of the protein. Heparan sulfates extracted from various mammalian tissues were also able to potentiate aFGF mitogenic activity. On a mass basis they were in general less efficient than heparin; however, heparan sulfate prepared from medium conditioned by 3T3 fibroblasts is more efficient than heparin both on a mass and molar basis. A highly sulfated oligosaccharide isolated after digestion of pancreas heparan sulfate with heparitinase I is more active than the intact molecule, reaching a potentiating effect equivalent to that of lung heparin, whereas an N-acetylated oligosaccharide isolated after nitrous acid degradation is inactive. These data suggest that the mitogenic activity of aFGF is primarily potentiated by interacting with highly sulfated regions of heparan sulfates chains.