Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Free Radic Res Commun ; 19(5): 315-21, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8314112

RESUMO

The production of formaldehyde from tris(hydroxymethyl) aminomethane(Tris) by interaction with hydroxyl radicals(.OH) was studied, since the reaction mixture from the Fenton reaction performed in Tris/HCl buffer was found to be color-developed by colorimetric determination of formaldehyde. The absorption spectrum of chromogens was identical to that of authentic formaldehyde. Color development, which required the presence of Tris, hydrogen peroxide and cupric ions in the Fenton reaction mixture, was inhibited by the addition of hydroxyl radical scavengers such as glucose or hyaluronic acid. These results indicated that formaldehyde was produced when Tris interacted with .OH. With structures similar to Tris, Good's buffers were also found to produce formaldehyde by interaction with .OH. Analysis of formaldehyde derived from these buffers may provide a simple and convenient assay for detecting .OH generation. In evaluating effects of .OH on the biological system in Tris/HCl buffer or certain Good's Buffers, .OH loss may be due to interactions of .OH with these buffers. The formaldehyde produced as a result of such interactions may affect biological systems.


Assuntos
Formaldeído/síntese química , Radical Hidroxila/química , Trometamina/química , Soluções Tampão , Cobre/química , Interações Medicamentosas , Formaldeído/análise , Glucose/química , Ácido Hialurônico/química
2.
Nihon Yakurigaku Zasshi ; 100(4): 359-65, 1992 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-1446887

RESUMO

Antinociceptive effects of sodium hyaluronate (Na-HA) were studied on the basis of improvement in the graded abnormal gait elicited by arthritis induced by intra-articular administration of monosodium urate crystal (MSU) to rats. One hour before MSU injection, intra-articular administration of a 1.0% solution of Na-HA with different molecular weights, ranging from 4.70 x 10(5) to 2.02 x 10(6) (HA-200), improved the score of abnormal gait in a molecular weight-dependent manner in the experimental arthritis model. Similarly, administrations of HA-200 at concentrations ranging from 0.1 to 1.0% prior to MSU treatment resulted in improvement of the score in abnormal gait in a dose-dependent manner. To elucidate the antinociceptive mechanisms of Na-HA, effects of pretreatment with Na-HA (1.0%) of different molecular weights on prostaglandin E2 (PGE2) and bradykinin (BK) releases in synovial fluid 3 hr after MSU injection were studied. Increases in PGE2 and BK concentration in the synovial fluid were depressed in a molecular weight-dependent manner by Na-HA (1.0%) pretreatment. These results indicate that Na-HA attenuates the nociceptive responses inflicted by the MSU-induced arthritis. Such an antinociceptive effect may be due to the inhibition of PGE2 and BK synthesis in the synovial joint of rats.


Assuntos
Analgésicos/uso terapêutico , Artrite/tratamento farmacológico , Ácido Hialurônico/uso terapêutico , Analgésicos/farmacologia , Animais , Artrite/induzido quimicamente , Artrite/metabolismo , Bradicinina/metabolismo , Dinoprostona/metabolismo , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Masculino , Peso Molecular , Ratos , Ratos Wistar , Líquido Sinovial/metabolismo , Ácido Úrico
3.
Nihon Yakurigaku Zasshi ; 100(1): 67-76, 1992 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-1644371

RESUMO

Sodium hyaluronate (HA) with a molecular weight of approximately 600,000-1,200,000 is reportedly effective against osteoarthritis (OA). However, since HA with higher molecular weight is expected to be more effective against OA, we investigated the effects of HA (SL-1010) newly produced by fermentation with a molecular weight of 1,800,000-2,100,000 on the experimental OA induced by intraarticular injection of papain, into the knee joint of the rabbit, in comparison with those of HA with a molecular weight of about 950,000 (HA-95). When 0.4, 0.8, and 1.6% papain (0.5ml) was injected into the knee joint of the animal twice with a 3-day interval, there were dose-dependent degenerative changes and a decrease in sulfated glycosaminoglycan (S-GAG) in the articular cartilage with slight synovial inflammatory changes 6 weeks after the final injection of papain. In this OA model, intraarticular application of SL-1010 slightly reduced the degeneration of articular cartilage, compared with the injections of HA-95 or saline (control). SL-1010 also caused a significant recovery in the S-GAG level which was decreased in the cartilage of the OA model, compared with the control. In addition, SL-1010 inhibited the release of 35S-GAG from the cartilage obtained from normal and OA model joints. These results suggest that SL-1010 is effective in inhibiting the degeneration of cartilage in the OA model, probably due to the recovery of the S-GAG level by reducing the release of S-GAG from the cartilage.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Glicosaminoglicanos/análise , Ácido Hialurônico/farmacologia , Osteoartrite/tratamento farmacológico , Animais , Cartilagem Articular/patologia , Modelos Animais de Doenças , Ácido Hialurônico/administração & dosagem , Injeções Intra-Articulares , Masculino , Peso Molecular , Osteoartrite/induzido quimicamente , Osteoartrite/patologia , Papaína/administração & dosagem , Papaína/farmacologia , Coelhos , Radioisótopos de Enxofre
4.
Nihon Yakurigaku Zasshi ; 100(1): 77-86, 1992 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-1644372

RESUMO

Effects of SL-1010 on the experimental osteoarthritis (OA) produced by intra-articular injection of papain, proteolytic enzyme, in the knee joint of the guinea pigs were histologically and biochemically investigated. In addition, experimental conditions to produce OA in guinea pig knee joint were also examined, since papain-induced OA has been mainly studied in rabbits. Six weeks after intra-articular injection of papain (1%, 0.1 ml), there were inflammatory reactions of the synovial membrane, degenerative changes in chondrocytes and the matrix of the articular cartilage, a decrease in the Safranin-O staining intensity and lowering of sulfated glycosaminoglycan. Electronmicroscopic observations revealed that the amorphous layer had disappeared and large bundles of unit collagen fibers and larger collagen fibers had appeared in the cartilage matrix. In the OA model, SL-1010 reduced the inflammatory reactions of the synovial membrane, inhibited development of degenerative changes in chondrocytes and the matrix of the articular cartilage and recovered the Safranin-O staining intensity. The sulfated glycosaminoglycan contents in the cartilage was significantly increased in the SL-1010-treated group, compared with the control group. The electromicroscopically observed charges in the papain-injected knee joint of the control group were rarely detected in the SL-1010-treated group. These results suggest that SL-1010 inhibits degenerative changes in the chondrocytes and the matrix probably by reducing synovial inflammation and protection of the cartilage in the OA model of guinea pigs.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Glicosaminoglicanos/análise , Ácido Hialurônico/farmacologia , Osteoartrite/tratamento farmacológico , Animais , Cartilagem Articular/química , Cartilagem Articular/patologia , Feminino , Cobaias , Ácido Hialurônico/administração & dosagem , Injeções Intra-Articulares , Articulação do Joelho/patologia , Microscopia Eletrônica , Peso Molecular , Osteoartrite/induzido quimicamente , Osteoartrite/patologia , Papaína/administração & dosagem , Papaína/farmacologia
5.
Chem Pharm Bull (Tokyo) ; 38(7): 1953-6, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2268896

RESUMO

The concentration and degradation of hyaluronic acid in the synovial fluid of carrageenin-induced arthritic joints of rabbits was studied. A 0.5-ml volume of 1% lambda-carrageenin was intra-articularly injected three times into a right knee joint, and saline into a left. After 5 d from the last injection, inflammatory changes were observed in the synovial membrane and synovial fluid, but not in the articular cartilage. In the inflammatory synovial fluid, lipid peroxide content, phosphatase activity and cell counts were significantly increased, but the copper concentration was not changed. Concentration of polymeric hyaluronic acid and total hyaluronic acid were determined by high-performance liquid chromatography using gel-permeation columns. Total hyaluronic acid was appreciably decreased in the inflammatory fluid. The polymeric hyaluronic acid determined was 38% of the total hyaluronic acid in the inflammatory fluid and 74% in the control fluid. This suggests that in the inflammatory fluid, molecular weights of hyaluronic acid are distributed in the broader range. The concentration of chondroitin sulphates was similar in both the inflammatory fluid and the control fluid, but the content ratio of chondroitin sulphates to hyaluronic acid was higher in the inflammatory fluid. In the inflamed synovial membrane, synthesis of hyaluronic acid as measured by incorporation of [14C]glucosamine into glycoconjugates was increased by about twice that in the control membrane.


Assuntos
Artrite Experimental/metabolismo , Ácido Hialurônico/análise , Líquido Sinovial/química , Animais , Carragenina , Cartilagem Articular/metabolismo , Joelho , Masculino , Peso Molecular , Coelhos , Membrana Sinovial/metabolismo
6.
Leuk Lymphoma ; 1(5-6): 353-9, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-20394564

RESUMO

A 10-month-old male infant underwent splenectomy because of life-threatening hypersplenism due to malignant histiocytosis. The spleen tissue positive for herpes simplex virus (HSV)-DNA, histologically and immunologically revealed a marked B cell depletion replaced by proliferation of activated cytotoxic T cells. S100-positive histiomonocytoid cells and lysozyme-positive hemophagocytes were also significantly increased. No metaphases were obtained by cytogenetic studies and Southern blot analysis of spleen cell DNA demonstrated only germ bands of immunoglobulin and both T gamma and beta genes, providing no evidence of monoclonality in this case of so-called malignant histiocytosis.

7.
Arch Biochem Biophys ; 266(1): 201-9, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3178223

RESUMO

We have previously reported that naturally occurring sulfated glycosaminoglycans having a chondroitin-type structure and glycosaminoglycan polysulfate (GAGPS, a persulfated derivative of chondroitin sulfate) caused a specific stimulation of hyaluronic acid synthesis in rabbit knee synovial membranes [H. Nishikawa et al. (1985) Arch. Biochem. Biophys. 240, 146-153]. In the present study, the interaction of [3H]GAGPS and the surface of the rabbit knee synovial membranes and the relationship between this interaction and the stimulatory effect of GAGPS on the hyaluronic acid synthesis were examined in order to define the stimulatory mechanism of hyaluronic acid synthesis by GAGPS. A part of the [3H]GAGPS taken up by the synovial membranes was released from the membranes by trypsin treatment. The interaction of [3H]GAGPS and the surface of the isolated synovial membranes was diminished by pretreatment of the membranes with proteases or chelating reagents. Pretreatment of synovial membranes with trypsin or ethylene glycol bis(beta-aminoethyl ether) N,N'-tetraacetic acid had little effect on the basal hyaluronic acid synthesis but caused the loss of GAGPS-induced stimulation of hyaluronic acid synthesis accompanied by significant decrease (20% P less than 0.05-P less than 0.01) in the interaction between GAGPS and the surface of the synovial membranes. Dermatan sulfate having a chondroitin-type structure also stimulated hyaluronic acid synthesis but this effect was not additive to the stimulation of hyaluronic acid synthesis by GAGPS. Heparin had no effect on either the basal hyaluronic acid synthesis or the GAGPS-induced stimulation of hyaluronic acid synthesis. These results indicate that binding of GAGPS to certain distinct protein components on the surface of synovial membranes is involved in the stimulatory mechanism of hyaluronic acid synthesis by GAGPS, and that the binding may be mediated by Ca2+ ion. The binding was also found to be specific for sulfated glycosaminoglycans having a chondroitin-type structure.


Assuntos
Cálcio/fisiologia , Glicosaminoglicanos/farmacologia , Ácido Hialurônico/biossíntese , Membrana Sinovial/metabolismo , Animais , Glicosaminoglicanos/metabolismo , Técnicas In Vitro , Ligação Proteica , Coelhos , Propriedades de Superfície , Tripsina/farmacologia
8.
J Chromatogr ; 435(2): 335-42, 1988 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-3346344

RESUMO

The simultaneous analysis of the molecular weight and concentration of hyaluronic acid in biological samples using high-performance liquid chromatography with two gel permeation columns is described. The elution volumes of various molecular weights of hyaluronic acids were linearily related to the logarithms of their molecular weights up to 600,000. The concentration of hyaluronic acid could be determined in the range from 20 to 100 micrograms/ml, i.e., from 4 to 20 micrograms per 200 microliter injected. The method was applied to the analysis of several animal skin extracts and rabbit synovial fluid. Skin extracts from mouse, rat, guinea-pig and rabbit could be chromatographed without prior isolation and purification. Hyaluronic acids in skin were separated clearly from chondroitin sulphates and their concentrations were determined. The molecular weights were estimated simultaneously to be more than 10(6). Rabbit synovial fluids from intact joints and saline- and carrageenin-treated joints could be chromatographed directly. The chromatograms showed that the concentration of hyaluronic acid in carrageenin-treated synovial fluid is lower than that in saline-treated fluid and the molecular weight distribution is broader. This technique enabled the rapid analysis of hyaluronic acid present at low levels in biological samples.


Assuntos
Ácido Hialurônico/análise , Pele/análise , Líquido Sinovial/análise , Animais , Cromatografia em Gel , Sangue Fetal/análise , Cobaias , Humanos , Masculino , Camundongos , Peso Molecular , Coelhos , Ratos , Espectrofotometria Ultravioleta
9.
Arch Biochem Biophys ; 240(1): 146-53, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-4015094

RESUMO

The effect of various sulfated glycosaminoglycans on glycoconjugates syntheses in synovial membranes of rabbit knee joints in culture was investigated by two different approaches. In the first approach, synovial membranes isolated from rabbit knee joints were cultured in the presence of sulfated glycosaminoglycans and [14C]glucosamine. In the second approach, solutions of sulfated glycosaminoglycans were injected into rabbit knee joints and synovial membranes isolated from the joints were cultured in the presence of [14C]glucosamine. The major part of [14C]glucosamine-labeled glycoconjugates associated with the synovial membranes and secreted into culture medium was hyaluronic acid. Of the natural glycosaminoglycans tested, dermatan sulfate gave the maximum stimulation of hyaluronic acid synthesis followed by chondroitin 4- and 6-sulfate. Heparin, heparan sulfate, keratan sulfate, keratan polysulfate, and hyaluronic acid had no significant effect. Of the chemically polysulfated glycosaminoglycans, GAGPS (a persulfated derivative of chondroitin sulfate) gave high stimulation but N-acetylchitosan 3,6-disulfate had no effect. The effect of sulfated glycosaminoglycans on hyaluronic acid synthesis was the same in both experimental approaches. The increase in the amount of secreted hyaluronic acid in culture medium paralleled that in synovial membranes. The results indicate that the galactosamine-containing sulfated glycosaminoglycans have a specific stimulatory effect on hyaluronic acid synthesis. A high degree of sulfation of the molecules appeared to potentiate the stimulatory effect.


Assuntos
Glicosaminoglicanos/farmacologia , Ácido Hialurônico/biossíntese , Membrana Sinovial/metabolismo , Animais , Cromatografia em Gel , Técnicas de Cultura , Glucosamina/metabolismo , Concentração de Íons de Hidrogênio , Articulação do Joelho , Peso Molecular , Coelhos , Sulfatos/farmacologia
10.
Biochim Biophys Acta ; 646(3): 402-10, 1981 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-7284369

RESUMO

Plasma membranes were isolated from HM7 melanoma cells grown in the presence of [3H]glucosamine and Na2(35)SO4 or [3H]mannose and [14C]glucosamine. The labeled glycoconjugates were solubilized with 0.6 M lithium diiodosalicylate/0.5% Triton X-100. Fractionation of glycoconjugates by repeated chromatography on columns of Sepharose CL-6B and DEAE-Sepharose and by affinity chromatography on WGA-Sepharose yielded three radiochemically homogeneous glycoproteins. One of these having an apparent molecular weight of 100,000 was found to contain clusters of (AcNeu)1 or 2 leads to [Gal leads to GalNAc] linked O-glycosidically to the protein. One other glycoprotein contained both O-glycosidically and N-glycosidically-linked oligosaccharides, and the third contained only N-glycosidically-linked carbohydrates. Preliminary results indicate that the 100,000 molecular weight mucin-type glycoprotein is present in significantly reduced quantitites in cultured human fetal uveal melanocytes. Further, the bulk of the glycoproteins from the melanocytes were of lower molecular size compared to those from the melanoma cells.


Assuntos
Glicoproteínas/isolamento & purificação , Melanoma/análise , Linhagem Celular , Membrana Celular/análise , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Feminino , Glucosamina/metabolismo , Humanos , Manose/metabolismo , Peso Molecular , Gravidez
11.
J Antibiot (Tokyo) ; 33(8): 791-5, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6776084

RESUMO

A new antibiotic, B-1008 has been isolated from the cultured broth of Pseudomonas fluorescens No. 101 B-13L. B-1008 is a water-soluble basic substance containing the spermidine moiety and possessing antibacterial activity against a wide range of bacterial species.


Assuntos
Antibacterianos/biossíntese , Espermidina/análogos & derivados , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Fenômenos Químicos , Química , Físico-Química , Feminino , Hidrólise , Masculino , Camundongos , Pseudomonas fluorescens/metabolismo , Espermidina/análise , Espermidina/biossíntese , Espermidina/isolamento & purificação , Espermidina/farmacologia
12.
Anal Biochem ; 91(1): 186-93, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9762098

RESUMO

The synthetic glycosides, p-nitrophenyl- and o-nitrophenyl-2-acetamido-2-deoxy-3-O-beta-D-galactopyranosyl-alpha- D-galactopyranosides, were found to be effective chromogenic substrates for an endo-alpha-N-acetyl-D-galactosaminidase. We did not experience any problems when these substrates were used for the screening of column fractions during the purification of the endoenzyme from Diplococcus pneumoniae culture filtrates. However, it should be pointed out that a combination of exo-beta-galactosidase, capable of cleaving beta 1-->3 linkages, and an exo-alpha-N-acetyl galactosaminidase would also liberate nitrophenol from the above substrates. The enzyme had no action on several other synthetic glycosides tested indicating the strict specificity of this enzyme for the disaccharide Gal beta-->GalNAc linked via an alpha-linkage to the aglycone. The enzyme was inactive when the aglycone was methanol but shows activity against the glycosides of phenol, nitrophenols, serine, and threonine. The use of p-nitrophenyl-2-acetamido-2-deoxy-3-O-beta -D-galactopyranosyl-beta-D-galactopyranoside, which is a competitive inhibitor of the endoenzyme, as an affinity ligand for the purification of the enzyme is described.


Assuntos
Hexosaminidases/metabolismo , Marcadores de Afinidade , Cromatografia de Afinidade/métodos , Compostos Cromogênicos , Glicosídeos/síntese química , Glicosídeos/química , Hexosaminidases/isolamento & purificação , Cinética , Ligantes , Streptococcus pneumoniae/enzimologia , Especificidade por Substrato , alfa-N-Acetilgalactosaminidase
13.
J Biol Chem ; 252(23): 8609-14, 1977 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-21877

RESUMO

An enzyme that hydrolyzes the O-glycosidic linkage between alpha-N-acetyl-D-galactosamine and serine or threonine in mucins and mucin-type glycoproteins was purified by chromatography on an Affi-Gel 202 column or isoelectric focusing from filtrates of Diplococcus pneumoniae cultures. The final preparations were free of protease and a wide range of other glycosidase activities. The preparation obtained by isoelectric focusing was shown to consist of a single protein by gel filtration and sodium dodecyl sulfate-gel electrophoresis. This preparation had an apparent molecular weight of about 160,000, determined by gel filtration, an optimum pH of 7.6, and an isoelectric point in the range pH 8 to 9. The enzyme releases the disaccharide Gal-GalNAc from a variety of glycopeptide and glycoprotein substrates and appears to have a specific requirement for an unsubstituted galactose in the nonreducing terminus and an alpha linkage between N-acetylgalactosamine and the aglycone. This is the only endoenzyme known capable of cleaving the linkage between a carbohydrate and serine or threonine residues in glycoproteins. The ability of this enzyme to act on macromolecular substrates and its pH optimum makes it ideally suited to explore the distribution and function of mucin-type glycoproteins on normal and cancer cell surfaces.


Assuntos
Hexosaminidases/metabolismo , Streptococcus pneumoniae/enzimologia , Acetilglucosaminidase , Glicoproteínas , Hexosaminidases/isolamento & purificação , Cinética , Serina , Especificidade por Substrato , Treonina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA