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Rocha,H.A.O.; Franco,C.R.C.; Trindade,E.S.; Carvalho,L.C.M.; Veiga,S.S.; Leite,E.L.; Dietrich,C.P.; Nader,H.B.. |
Fucans, a family of sulfated polysaccharides present in brown seaweed, have several biological activities. Their use as drugs would offer the advantage of no potential risk of contamination with viruses or particles such as prions. A fucan prepared from Spatoglossum schröederi was tested as a possible inhibitor of cell-matrix interactions using wild-type Chinese hamster ovary cells (CHO-K1) and the mutant type deficient in xylosyltransferase (CHO-745). The effect of this polymer on adhesion properties with specific extracellular matrix components was studied using several matrix proteins as substrates for cell attachment. Treatment with the polymer inhibited the adhesion of fibronectin to both CHO-K1 (2 x 10(5))()and CHO-745 (2 x 10(5) and 5 x 10(5))... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: CHO cells; Extracellular matrix proteins; Fucan; Glycosaminoglycans; Cell adhesion; Brown algae. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000500009 |
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Nader,H.B.; Pinhal,M.A.S.; Baú,E.C.; Castro,R.A.B.; Medeiros,G.F.; Chavante,S.F.; Leite,E.L.; Trindade,E.S.; Shinjo,S.K.; Rocha,H.A.O.; Tersariol,I.L.S.; Mendes,A.; Dietrich,C.P.. |
The anticlotting and antithrombotic activities of heparin, heparan sulfate, low molecular weight heparins, heparin and heparin-like compounds from various sources used in clinical practice or under development are briefly reviewed. Heparin isolated from shrimp mimics the pharmacological activities of low molecular weight heparins. A heparan sulfate from Artemia franciscana and a dermatan sulfate from tuna fish show a potent heparin cofactor II activity. A heparan sulfate derived from bovine pancreas has a potent antithrombotic activity in an arterial and venous thrombosis model with a negligible activity upon the serine proteases of the coagulation cascade. It is suggested that the antithrombotic activity of heparin and other antithrombotic agents is due... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Heparin; Anticlotting activity heparan sulfate; Antithrombotic activity low molecular weight heparins; Preparation and antithrombotic activity antithrombotic agents; Development for clinical use crustacean heparin-like compounds; Antithrombotic activity antithrombotic agents vascular endothelial cells. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000600002 |
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Silva,T.M.A.; Alves,L.G.; Queiroz,K.C.S. de; Santos,M.G.L.; Marques,C.T.; Chavante,S.F.; Rocha,H.A.O.; Leite,E.L.. |
The brown algae Padina gymnospora contain different fucans. Powdered algae were submitted to proteolysis with the proteolytic enzyme maxataze. The first extract of the algae was constituted of polysaccharides contaminated with lipids, phenols, etc. Fractionation of the fucans with increasing concentrations of acetone produced fractions with different proportions of fucose, xylose, uronic acid, galactose, and sulfate. One of the fractions, precipitated with 50% acetone (v/v), contained an 18-kDa heterofucan (PF1), which was further purified by gel-permeation chromatography on Sephadex G-75 using 0.2 M acetic acid as eluent and characterized by agarose gel electrophoresis in 0.05 M 1,3 diaminopropane/acetate buffer at pH 9.0, methylation and nuclear magnetic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fucan; Anticoagulant activity; Sulfated polysaccharides; Brown algae; Padina gymnospora. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2005000400005 |
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Franco,C.R.C.; Rocha,H.A.O.; Trindade,E.S.; Santos,I.A.N.; Leite,E.L.; Veiga,S.S.; Nader,H.B.; Dietrich,C.P.. |
We have examined the role of cell surface glycosaminoglycans in cell division: adhesion and proliferation of Chinese hamster ovary (CHO) cells. We used both wild-type (CHO-K1) cells and a mutant (CHO-745) which is deficient in the synthesis of proteoglycans due to lack of activity of xylosyl transferase. Using different amounts of wild-type and mutant cells, little adhesion was observed in the presence of laminin and type I collagen. However, when fibronectin or vitronectin was used as substrate, there was an enhancement in the adhesion of wild-type and mutant cells. Only CHO-K1 cells showed a time-dependent adhesion on type IV collagen. These results suggest that the two cell lines present different adhesive profiles. Several lines of experimental... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: CHO cells; Extracellular matrix proteins; Proteoglycans; Glycosaminoglycans; Cell adhesion; Cell proliferation. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000800001 |
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Nader,H.B.; Chavante,S.F.; dos-Santos,E.A.; Oliveira,F.W.; de-Paiva,J.F.; Jerônimo,S.M.B.; Medeiros,G.F.; de-Abreu,L.R.D.; Leite,E.L.; de-Sousa-Filho,J.F.; Castro,R.A.B.; Toma,L.; Tersariol,I.L.S.; Porcionatto,M.A.; Dietrich,C.P.. |
The distribution and structure of heparan sulfate and heparin are briefly reviewed. Heparan sulfate is a ubiquitous compound of animal cells whose structure has been maintained throughout evolution, showing an enormous variability regarding the relative amounts of its disaccharide units. Heparin, on the other hand, is present only in a few tissues and species of the animal kingdom and in the form of granules inside organelles in the cytoplasm of special cells. Thus, the distribution as well as the main structural features of the molecule, including its main disaccharide unit, have been maintained through evolution. These and other studies led to the proposal that heparan sulfate may be involved in the cell-cell recognition phenomena and control of cell... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Heparin - occurrence and function; Heparan sulfate - occurrence and function; Heparin - invertebrates; Heparan sulfate - invertebrates; Heparin and heparan sulfate - structure. |
Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000500005 |
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Albuquerque,I.R.L.; Queiroz,K.C.S.; Alves,L.G.; Santos,E.A.; Leite,E.L.; Rocha,H.A.O.. |
Fucan is a term used to denote a family of sulfated L-fucose-rich polysaccharides which are present in the extracellular matrix of brown seaweed and in the egg jelly coat of sea urchins. Plant fucans have several biological activities, including anticoagulant and antithrombotic, related to the structural and chemical composition of polysaccharides. We have extracted sulfated polysaccharides from the brown seaweed Dictyota menstrualis by proteolytic digestion, followed by separation into 5 fractions by sequential acetone precipitation. Gel electrophoresis using 0.05 M 1,3-diaminopropane-acetate buffer, pH 9.0, stained with 0.1% toluidine blue, showed the presence of sulfated polysaccharides in all fractions. The chemical analyses demonstrated that all... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Fucan; Fucoidan; Anticoagulant drugs; Brown algae; Antithrombotic agents. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000200002 |
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