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1.
Braz. J. Pharm. Sci. (Online) ; 58: e19542, 2022. graf
Artigo em Inglês | LILACS | ID: biblio-1384004

RESUMO

Abstract The main aim of the study is to quantify the cytotoxic property of the Fucoidan extracted from the Turbinaria conoides using the MTT assay with the standard fucose. Fucoidan was extracted using the soaked water method and it was determined using the HPLC procedure the obtained Test sample Fucoidan extracted from the Turbinaria conoides and standard fucose was subjected to the cytotoxicity assay against the MCF7 Human breast cancer cell line, A549 lung cancer cell line, and L929 normal mouse fibroblast cell line. From the results it was found that the Test sample showed good IC50 value for MCF7 cell line then A549 with an increasing concentration 24 hours incubation at 37°C The IC50 for MCF7 was 115.21 µg/ml and A549 396.46µg/ml and the Fucoidan extract was checked for its cytotoxicity against the normal mouse fibroblast cell line L929, Fucoidan was found non-lethal to the L929 mouse fibroblast normal cell line. Standard fucose also gave a significant result towards MCF7 and against the L929. This indicates that the Fucoidan extracted from Tubinaria conoides shows better anticancer potential in it. Hence its application can be further extended in the pharmacological fields.


Assuntos
Técnicas In Vitro/instrumentação , Citotoxinas/efeitos adversos , Células MCF-7 , Células A549 , Neoplasias da Mama/patologia , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Concentração Inibidora 50 , Fibroblastos/classificação , Fucose/análogos & derivados , Neoplasias Pulmonares/patologia
2.
Rev. chil. nutr ; 46(5): 626-632, oct. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1042704

RESUMO

Los oligosacáridos de la leche materna (HMOs) son unas 200 moléculas distintas sintetizadas y secretadas por la glándula mamaria a partir de lactosa a la que diversos enzimas unen monosacáridos simples (glucosa, galactosa, n-acetil galactosamina, fucosa y ácido siálico). Estas uniones y sus diferentes orientaciones espaciales generan una gran diversidad de estructuras químicas y de funcionalidades. La concentración de los HMOs es mayor en el calostro (± 25 g/L), está relacionada con la duración del embarazo y la lactancia: disminuyen progresivamente hasta la mitad de los niveles iniciales. La genética materna influye en el perfil de algunos HMOs; el gen FUT2, que codifica la síntesis de la fucosiltransferasa 2 (FUT2) condiciona el llamado carácter secretor en 75-85% de las mujeres y hace que los antígenos del grupo ABO(H) sean secretados en los líquidos orgánicos (saliva, lágrimas, semen). La ausencia de actividad del gen FUT2 condiciona el carácter no-secretor (15-25% de las mujeres). La actividad del gen FUT3 condiciona la actividad de la fucosiltransferasa 3 (FUT3) que se asocia con el grupo sanguíneo Lewis+ mientras que su ausencia caracteriza a los portadores como Lewis 0. Los HMOs son absorbidos a nivel del intestino como trazas (1%) pero incluso en esas cantidades ejercerían efectos sistémicos.


Human milk oligosaccharides (HMOs) are a family of some 200 different molecules synthesized by the mammary gland. At the core is a molecule of lactose, which is linked by different enzymes to glucose, galactose, n-acetyl galactosamine, fucose or sialic acid. These linkages and their different spatial orientation generate, besides the possibilities of numerous chemical structures, the potential for different spatial isomers. The concentration of HMOs in human milk depends on pregnancy and breastfeeding duration. They are highest in colostrum (± 25 g/L) and decrease over time to half this initial level. Maternal genetics modifies the concentration and profile of some oligosaccharides. For example, the FUT2 gene codifies the synthesis of fucosyltransferase 2 (FUT2) whose activity generates the secretor status for antigens of the ABO(H) blood group in organic fluids (saliva, milk, tears, semen) among 75-85% of the carriers of the trait. The absence of activity of the FUT2 gene conditions the non-secretor status (15-25% of women). The FUT3 gene regulates the activity of the fucosyltransferase 3 (FUT3) that is associated with the Lewis blood group. Traces of HMOs (1%) are absorbed in the intestinal tract, however, they exert important systemic effects even at low concentrations.


Assuntos
Humanos , Oligossacarídeos , Carboidratos , Leite Humano , Fucose , Lactose
3.
Biol. Res ; 33(3/4): 215-226, 2000. ilus
Artigo em Inglês | LILACS | ID: lil-454063

RESUMO

The structural diversity of the many oligosaccharide chains of surface glycoconjugates renders them likely candidates for modulators of cell-interactions, cellular movements, differentiation, and cellular recognition. A selection of different lectins was used to investigate the appearance of cellular distribution and changes in sugar residues during tooth development in the polyphyodont lizard, Liolaemus gravenhorsti. Lectins from three groups were used: (1) N-acetylgalactosamine specificity: BS-1, PNA, RCA-120; (2) N-acetylglucosamine specificity: ECA; and (3) fucose specificity: UEA 1 and LTA.. Digital images were processed using Scion Image. Grayscale graphics in each image were obtained. The lectins used showed a strong, wide distribution of the L-fucose and N-acetylgalactosamine at the cell surface and in the cytoplasm of multinucleate odontoclast cell, while mononuclear odontoclast cells showed no binding, suggesting some roles that the residues sugar might play in the resorption of dentine or with multinucleation of odontoclast after the attachment to the dentine surface in this polyphyodont species. Further studies must be planned to determine the specific identities of these glycoconjugates,and to elucidate the roles played by these sugar residues in the complex processes related to odontogenesis in polyphyodont species.


Assuntos
Animais , Acetilgalactosamina/análise , Acetilglucosamina/análise , Dente/química , Fucose/análise , Lectinas , Lagartos , Osteoclastos/química , Dente/citologia , Histocitoquímica , Odontogênese
4.
Braz. j. med. biol. res ; 31(2): 207-13, feb. 1998. graf
Artigo em Inglês | LILACS | ID: lil-212571

RESUMO

The efficiency and reliability of radioactive fucose as a specific label for newly synthesized glycoproteins were investigated. Young adult male rabbits were injected intravitreally with [3H]-fucose, [3H]-galactose, [3H]-mannose, N-acetyl-[3H]-glucosamine or N-acetyl-[3H]-mannosamine, and killed 40 h after injection. In another series of experiments rabbits were injected with either [3H]-fucose or several tritiated amino acids and the specific activity of the vitreous proteins was determined. Vitreous samples were also processed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and histological sections of retina, ciliary body and lens (the eye components around the vitreous body) were processed for radioautography. The specific activity (counts per minute per microgram of protein) of the glycoproteins labeled with [3H]-fucose was always much higher than that of the proteins labeled with any of the other monosaccharides or any of the amino acids. There was a good correlation between the specific activity of the proteins labeled by any of the above precursors and the density of the vitreous protein bands detected by fluorography. This was also true for the silver grain density on the radioautographs of the histological sections of retina, ciliary body and lens. The contribution of radioautography (after[3H]-fucose administration) to the elucidation of the biogenesis of lysosomal and membrane glyco-proteins and to the determination of the intracellular process of protein secretion was reviewed. Radioactive fucose is the precursor of choice for studying glycoprotein secretion because it specific, efficient and practical for this purpose.


Assuntos
Coelhos , Animais , Masculino , Fucose , Glicoproteínas/metabolismo , Traçadores Radioativos , Corpo Vítreo/química , Autorradiografia , Eletroforese em Gel de Poliacrilamida , Dodecilsulfato de Sódio
5.
Biocell ; 20(1): 11-20, Apr. 1996.
Artigo em Inglês | LILACS | ID: lil-336008

RESUMO

Fucosylated glycoconjugates play an important role in fertilization as the recognition signal of the zona pellucida. In this work, using "critical" concentrations of either, FITC Lotus tetragonolobus lectin or FITC alpha-L-fucosyl-BSA neoglycoprotein as molecular probes, population densities of fucosylated glycoconjugates and of their "complementary" molecules (carrying fucosyl receptors), were found all over the sperm surface with higher population densities in post acrosomal sheath, neck and midpiece. These results were compared with previously reported data on the population densities of lactosaminic compounds and their "complementary" molecules, obtained on same samples of spermatozoa. Statistical data demonstrate that fucosylated glycoconjugates share the same domains with biantennary N-acetyllactosaminic oligosaccharides carrying outer galactose and bisected N-acetylglucosamine residues. These domains highly differ with those of the lactosaminic glycoproteins carrying tri and tetraantennary N-acetyllactosaminic oligosaccharides. These studies also show that the domains of fucosylated glycoconjugates and their "complementary" molecules (carrying fucosyl receptors) locate in different zones of the spermatozoon than those of the compounds carrying beta-galactosyl receptors. Besides, the results suggest structural differences between fucosylated glycoconjugates of the acrosome, equatorial zone and post acrosomal sheath. This may be relevant to the different biological behavior of these compounds and zones, in fertilization.


Assuntos
Humanos , Masculino , Amino Açúcares/química , Fucose , Galactose , Glicoconjugados , Espermatozoides , Amino Açúcares/metabolismo , Hormônio Foliculoestimulante , Fucose , Galactose , Glicoconjugados , Hormônio Luteinizante/química , Hormônio Luteinizante/metabolismo , Lectinas , Estrutura Terciária de Proteína , Sítios de Ligação/fisiologia , Espermatozoides
6.
Rev. Soc. Bras. Med. Trop ; 29(2): 153-63, Mar.-Apr. 1996. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-187142

RESUMO

The Fucose-Mannose Ligand (FML) of Leishmania donovani is a complex glycoproteic fraction. Its potential use as a tool for diagnosis of human visceral leishmaniasis was tested with human sera from Natal, Rio Grande do Norte, Brazil. The FML-ELISA test, showed 100 per cent sensitivity and 96 per cent specificity, identifying patients with overt kala-azar (p < 0.001, when compared to normal sera), and subjects with subclinical infection. More than 20 per cent apparently healthy subjects with positive reaction to FML developed overt kala-azar during the following 10 months. In the screening of human blood donnors, a prevalence of 5 per cent of sororeactive subjects was detected, attaining 17 per cent in a single day. The GP36 glycoprotein of FHL is specifically reconized by human kala-azar sera. The immunoprotective effect of FML on experimental L. donovani infection was tested in swiss albino mice. The protection scheemes included three weekly doses of FML, supplemented or not with saponin by the subcutaneous or intraperitoneal routes and challenge with 2 x 10(7) amastigotes of Leishmania donovani. An enhancement of 80.0 per cent in antibody response (p < 0.001) and reduction of 85.5 per cent parasite liver burden (p < 0.001) was detected in animals immunized with FML saponin, unrespectively of the immunization route.


Assuntos
Humanos , Animais , Feminino , Camundongos , Antígenos de Protozoários/análise , Leishmania donovani/imunologia , Leishmaniose Visceral/diagnóstico , Proteínas de Protozoários/análise , Doadores de Sangue , Brasil/epidemiologia , Doença de Chagas/imunologia , Ensaio de Imunoadsorção Enzimática , Fucose/análise , Leishmania donovani/química , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/prevenção & controle , Ligantes , Manose/análise , Vacinação
7.
Acta bioquím. clín. latinoam ; 30(1): 49-58, mar. 1996. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-177465

RESUMO

El plasma seminal humano (PSH) de individuos normospérmicos y con diferentes patologías fue analizado por cromatografía de afinidad en Concanavalina-A Sepharose. Se obtuvieron dos fracciones mayoritarias, F1 y F2, en proporciones variables y con diferencias en la composición de monosacáridos y aminoácidos de acuerdo con el tipo de patología. Galactosa es el principal miembro, juntamenete con fucosa y proporciones variables de manosa, N-acetilglucosamina y N-acetilgalactosamina. Se encontraron diferencias en la estructura primaria de los glicanos (enlaces N- y O-glicosídicos) presentes en las fracciones de los individuos con diferentes patologías. En F1 todas las cadenas de oligosacáridos son del tipo O-glicosídica correspondiendo a glicoproteínas tipo mucina; en F2 se encontró una relación molar O-/N- es 5,3/1. La fracción de F1 de individuos azoospérmicos y oligozoospérmicos son del tipo O-glicosídico mientras que en vasectomizados la relación molar O-/N- es 1,7/1. En todos los casos, F2 presenta cadenas de oligosacáridos O- y N-glicosídicas en diferentes proporciones, con la excepción del plasma seminal de vasectomizado que pertenece al tipo O-glicosídico. Los resultados obtenidos sugieren que la composición de las fracciones F1 y F2 de donantes con diferentes patologías está caracterizada por diferencias importantes en el contenido de carbohidratos y pépticos


Assuntos
Humanos , Masculino , Concanavalina A , Cromatografia de Afinidade/métodos , Oligospermia/fisiopatologia , Sêmen/citologia , Vasectomia/efeitos adversos , Aminoácidos , Cromatografia em Gel , Fucose , Galactose , Glucose , Manose , Monossacarídeos , Mucinas , Oligospermia/diagnóstico , Oligospermia/etiologia , Sêmen/química
8.
Rev. oftalmol. venez ; 51(3-4): 63-6, jul.-dic. 1995. tab
Artigo em Espanhol | LILACS | ID: lil-259403

RESUMO

Evaluar el contenido de glicoproteínas en el vítreo y determinar las posibles modificaciones en relación al tiempo de fallecimiento, edad. Se obtuvo humor vítreo (HV) de 120 pacientes (60 hombres y mujeres), en edades comprendidas entre 20-40 años fallecidos recientemente por causas que no afectaban los tejidos oculares. Los resultados fueron sometidos a los análisis estadísticos habituales, calculándose las medias, desviaciones y los correspondientes errores estándares. Se practicó análisis de varianza (ANAVA) de los factores y tres períodos (4, 6 y 8 horas) a un nivel de significación del 0,01. Los valores promedios de fucosa, de PBH y de ácido siálico en los 120 HV fueron de 0,8798 ñ 0,1189; 8.18 ñ 0,62 y 13,09 ñ 0,50 mg/dl, sin diferencias entre los sexos. El ANAVA de dos vías demuestra que ni el sexo, ni el tiempo influyen significativamente sobre el contenido vítreo de fucosa, de PBH y de ácido siálico. La edad tampoco ejerce una influencia significativa sobre la composición glicoproteíca de HV, como lo demostró el análisis de varianza de una vía (f= 0,08 gl= 4/119 no significativo). El contenido de glicoproteínas en el HV humano, con pocas excepciones es muy similar al de la mayoría de las especies animales. La concentración de proteínas en el HV no es influenciada ni por el sexo ni por el tiempo de recolección postmortem. Entre 20 y 40 años no existe una influencia significativa de la edad sobre el contenido de glicoproteína vítrea


Assuntos
Humanos , Masculino , Feminino , Adulto , Morte , Fucose , Corpo Vítreo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Oftalmologia
9.
Ciênc. cult. (Säo Paulo) ; 46(4): 290-6, July-Aug. 1994. graf
Artigo em Inglês | LILACS | ID: lil-196744

RESUMO

Visceral leishmaniais or kala-azar, is a chronic and frequently lethal disease, caused by Leishmania donovani. Clinical signs include malaise, hepatosplenomegaly, hypergammaglobulinemia, fever, cachexia and progressive suppresion of the cellular immune response. Only few studies on prophylactic immunization against this disease have been understaken, mostly with crude antigens, and no vaccine against kala-azar is yet available. In previous studies, we have isolated the Fucose-Mannose Ligand (FML) of L. donovani that strongly and specifically inhibits the in vitro infection of macrophages by promastigotes and amastigotes. The FML behaves as a pontent immunogen for rabbits and mice, and is specifically recognized by kala-azar patient sera. The protective pontential of FML on kala-azar was now analyzed in the CB-hamster model. We studied the efect of three intraperitoneal weekly doses of FML (100 mg) in saponin (100 mg), folowed by an intracardiac injection of 107 amastigotes. Saponin- and saline-treated controls were also included. Protection was highly significant regarding the enhancement of anti-FML antibodies titers, the splenocyte proliferative response, and the intradermal delayed hypersensitivity reaction to antigen, as well as the decrease of the parasite burden in spleen and of splenomegaly. Protection to kala-azar was due to specific FML antigenic properties, since the results obtained by saponin alone were significantly different. We conclude that the use of FML and saponin as a vaccine reduced the disease impact and retarded its onset.


Assuntos
Animais , Masculino , Feminino , Cricetinae , Fucose/farmacologia , Leishmania donovani/imunologia , Leishmaniose Visceral/prevenção & controle , Manose/farmacologia , Vacinas Protozoárias/farmacologia , Ensaio de Imunoadsorção Enzimática , Fucose/administração & dosagem , Leishmania donovani/efeitos dos fármacos , Ligantes , Manose/administração & dosagem , Análise de Regressão , Fatores de Tempo , Vacinas Protozoárias/administração & dosagem
10.
Rev. cuba. pediatr ; 65(2): 138-44, mayo-ago. 1993. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-140834

RESUMO

Se describen 3 pacientes: 2 del sexo masculino y 1 del femenino, con enfermedad por almacenamiento lisosomal del tipo fucosidosis. En los 3 casos existió el antecedente de retardo psicomotor y posteriormente se hizo evidente el deterioro progresivo de las capacidades psíquicas motoras adquiridas. Todos tenían facies toscas, retardo mental profundo y alteraciones morfológicas en vértebras lumbares. Desde el punto de vista bioquímico, los 3 pacientes presentaron excreción urinaria de oligisacáridos ricos en fucosa, así como disminución de la actividad de la enzima alfa-L-fucosidasa en leucocitos. Se hace énfasis en la demostración del defecto enzimático como único criterio diagnóstico confirmatorio


Assuntos
Criança , Humanos , Masculino , Feminino , alfa-L-Fucosidase/sangue , Fucose/urina , Fucosidose/diagnóstico , Fucosidose/enzimologia , Oligossacarídeos/urina
11.
Bol. Hosp. San Juan de Dios ; 35(3): 135-40, mayo-jun. 1988. tab, ilus
Artigo em Espanhol | LILACS | ID: lil-77086

RESUMO

Con el propósito de conocer los niveles séricos de ácido siálico, 1-fucosa y fucosidasa, se cuantificaron sus valores en 107 adultos (25 a 90 años) sometidos a endoscopia oral. Con los resultados obtenidos se analiza su utilidad como método de pesquisa en el diagnóstico de cáncer gástrico. La muestra estudiada estuvo integrada por cuatro grupos: sin alteraciones endoscópicas (n=25); úlcera duodenal (n = 25); úlcera gástrica (n = 25) y cáncer gástrico (n = 32). Los valores promedio obtenidos para el ácido siálico fueron: 1,96; 1,19; 20,5 y 2,80 micronmol/ml; para la 1-fucosa: 9,32; 9,00; 10,8 y 13,0 mg/dl y para la actividad fucosidasa: 11,5; 10,2; 9,06 y 10,6 U/l respectivamente. El coeficiente de correlación ácido siálico-1-fucosa fue 0,80 (p < 0,01) en los grupos sin alteración y cáncer gástrico. La fucosidasa no tuvo variaciones significativas entre los diferentes grupos estudiados. Las determinaçöes de ácido siálico y 1-fucosa presentaron una sensibilidad del 81 y 74% respectivamente en pacientes portadores de cáncer gástrico pero ella fue de 97% cuando se consideran pacientes que tienen ácido siálico o 1-fucosa positivos. Porcentajes importantes de pacientes sin alteraciones endoscópicas o con otras afecciones gástricas cursan con valores positivos de ácido siálico y 1-fucosa. Por tratarse de procedimientos simples y sensibles, las ácido siálico y 1-fucosa. Por tratarse de procedimientos simpsles y sensibles, las determinaciones séricas de ácido siálico y 1-fucosa pudiera ser de utilidad para la detección de cáncer gástrico o de su control evolutivo


Assuntos
Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Ácidos Siálicos/sangue , alfa-L-Fucosidase/sangue , Fucose/sangue , Neoplasias Gástricas/diagnóstico
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