Consulta: creatorFacets:"Leite,E.L."
Registros recuperados: 7
Data/hora: 16/06/2024 17:36:12

A fucan from the brown seaweed Spatoglossum schröederi inhibits Chinese hamster ovary cell adhesion to several extracellular matrix proteins
Provedor de dados: 56
Autores: 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

Development of new heparin-like compounds and other antithrombotic drugs and their interaction with vascular endothelial cells
Provedor de dados: 56
Autores: 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

Sulfated fucan as support for antibiotic immobilization
Provedor de dados: 56
Autores: Araújo,P.M.; Oliveira,G.B.; Córdula,C.R.; Leite,E.L.; Carvalho Jr.,L.B.; Silva,M.P.C.
Xylofucoglucuronan from Spatoglossum schröederi algae was tested as a support for antibiotic immobilization. The polysaccharide (20 mg in 6 ml) was first activated using carbodiimide, 1-ethyl-3-(3-dimethylamino-propyl)carbodiimide methiodide (20 mg in 2 ml), under stirring for 1 h at 25ºC and pH from 4.5 to 5.0. After adjusting the pH to 8.0, either gentamicin or amikacin (62.5 mg in 1.25 ml) was then immobilized on this chemically modified polysaccharide with shaking for 24 h in a cold room. Infrared spectra of the activated carbodiimide xylofucoglucuronan showed two bands to carbonyl (C = O at 1647.9 and 1700.7 cm-1) and to amide (C&lt;FONT FACE=Symbol&gt;Ý&lt;/FONT&gt;-NH2) groups (1662.8 and 1714.0 cm-1). Microbial characterization of the derivatives...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Sulfated fucan; Immobilization; Antibiotics; Gentamicin; Amikacin.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000300002

Partial characterization and anticoagulant activity of a heterofucan from the brown seaweed Padina gymnospora
Provedor de dados: 56
Autores: 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

Heparan sulfate and control of cell division: adhesion and proliferation of mutant CHO-745 cells lacking xylosyl transferase
Provedor de dados: 56
Autores: 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

Heparan sulfates and heparins: similar compounds performing the same functions in vertebrates and invertebrates?
Provedor de dados: 56
Autores: 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

Heterofucans from Dictyota menstrualis have anticoagulant activity
Provedor de dados: 56
Autores: 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