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Search Results: 1 - 10 of 423460 matches for " Tania Maria S. Silva "
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Palladium(0)-catalyzed efficient synthesis of allylic N- and S-benzoheterocycles linked to unsaturated carbohydrate derivatives
Ronaldo Nascimento de Oliveira,Wilson S. do Nascimento,Girliane R. da Silva,Tania Maria S. Silva
Orbital : the Electronic Journal of Chemistry , 2012,
Abstract: An efficient strategy was developed to envisage the synthesis of new N- and S-benzoheterocycles attached to the C-4 position of pseudo-carbohydrates. The reaction was performed with unsaturated carbohydrates and benzoheterocycles as nucleophiles in the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium(0) and chelating bidentate ligand dppb. This strategy allowed easy access to benzoheterocyclic sugars in moderate-to-good yields. A preliminary study for antioxidant activities of O-glycosides 2,3-unsaturated was evaluated based on the 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging and 2,2-azinobis 3-ethylbenzothiozoline-6-sulfonic acid (ABTS) radical cation decolorization assay, and showed low-to-moderate activities.
Spatial and temporal variation of the nutrients in the sediment and leaves of two Brazilian mangrove species and their role in the retention of environmental heavy metals
Bernini, Elaine;Silva, Maria A. B. da;Carmo, Tania M. S. do;Cuzzuol, Geraldo R. F.;
Brazilian Journal of Plant Physiology , 2010, DOI: 10.1590/S1677-04202010000300005
Abstract: spatial and temporal variation of the nutrient concentrations in leaves and sediment between the roots of laguncularia racemosa (l.) gaertn. f and rhizophora mangle l. was analyzed in the mangrove forest of the estuary of s?o mateus river, espírito santo, brazil. in leaves, the nutrients followed the sequence: n> ca> k> mg> s> p> fe> mn> zn> cu, and there were significant differences between species and sites studied. in general, the levels of k were higher in the dry season compared to the rainy season for both species analyzed while ca and cu showed higher concentrations in the rainy season for laguncularia racemosa. in the sediment, the nutrients followed the sequence: mg> ca> fe> k> mn> p> zn> cu, in general, with lower concentrations at the site where the sediment was sandier. we observed a significant variation of nutrient concentrations in the sediment between the periods analyzed, but the seasonal pattern was not clear for all nutrients. nutrient concentration profile found in leaves of both plant species was not correlated with concentrations found in the respective sediments. the concentration factor was less than 1.0 for fe and between 1.0 and 3.7 for mn, zn and cu. these results provide physiological evidences about the relevance of these tree species for the role of mangroves as biogeochemical barriers to the transit of heavy metals.
Express?o do colágeno I em carcinomas epidermóides da cavidade oral
Martins, Gabriela Botelho;Reis, Sílvia Regina de Almeida;Silva, Tania Maria Correia;
Pesquisa Odontológica Brasileira , 2003, DOI: 10.1590/S1517-74912003000100016
Abstract: an analysis of the extracellular matrix at the invasive front of squamous cell carcinoma of the oral cavity may improve the understanding of tumour cell matrix interactions during malignancy growth. alterations in collagen i expression may influence cellular invasion and metastasis. in this work, 23 cases of squamous cell carcinoma were submitted to the anneroth's malignancy grading system1. h. e. and sirius red staining were used. immunohistochemical expression of collagen type i protein was observed in different malignancy scores. as a result, it was observed that the extracellular matrix in squamous cell carcinoma of the oral cavity shows different patterns of collagen i expression in low and high scores of malignancy.
Express o do colágeno I em carcinomas epidermóides da cavidade oral
Martins Gabriela Botelho,Reis Sílvia Regina de Almeida,Silva Tania Maria Correia
Pesquisa Odontológica Brasileira , 2003,
Abstract: A matriz extracelular no carcinoma epidermóide da cavidade oral sofre modifica es qualitativas e quantitativas durante a sua progress o. Estas altera es parecem possibilitar os processos de invas o e metástase que caracterizam as neoplasias malignas e s o mais evidentes na interface tumor-hospedeiro. No nosso estudo, 23 biópsias incisionais de carcinomas epidermóides de diversas localiza es da cavidade oral foram classificadas segundo o sistema de gradua o histológica preconizado por Anneroth et al.1 (1987). Foram utilizadas as colora es pela H. E. e a do tipo picrosirius, específica para colágeno. A express o imuno-histoquímica do colágeno tipo I foi analisada em les es com diferentes escores histológicos de malignidade. P de-se concluir que o colágeno apresenta diferentes padr es morfológicos, histoquímicos e imuno-histoquímicos em les es com altos e baixos escores de malignidade.
Brine shrimp bioassay of some species of Solanum from Northestern Brazil
Silva, Tania Maria S.;Nascimento, Roberto Jefferson B.;Batista, Michelle M.;Agra, Maria F.;Camara, Celso A.;
Revista Brasileira de Farmacognosia , 2007, DOI: 10.1590/S0102-695X2007000100008
Abstract: the methanolic extracts of 13 specieis of the genus solanum (solanaceae) have been tested for bioactivity in artemia salina. the extracts investigated were prepared from various parts (aerial parts, roots and fruits) of s. asperum, s. capsicoides, s. palinacantum, s. paludosum, s. paniculatum, s. paraibanum, s. sisymbriifolium, s. crinitum, s. diamantinense, s. megalonyx, s. torvum, s. asterophorum and s. stipulaceum. the lethal concentrations were determined for the extracts and among thirteen plants tested, four appear to be inactive. the extracts of the fruits of s. asperum (lc50 = 420.5 μg/ml) and s. paludosum (lc50 = 548.0 μg/ml), aerial parts of s. diamantinense (lc50 = 481.0 μg/ml) and s. sisymbrifolium (lc50 = 382.7 μg/ml), and the roots of s. asperum (lc50 = 593.4 μg/ml) and s. stipulaceum (lc50 = 823.1 μg/ml), all of which previously showed molluscicidal activity against biomphalaria glabrata were also found to be active in the present study with brine shrimp.
Hipersinais subcorticais no exame de ressonancia magnética: compara o entre idosos deprimidos e idosos normais
Novaretti Tania Maria da Silva,Marcolin Marco Ant?nio,Meira Jr Sílvio,Gelás Paulo de Lorenzetti
Arquivos de Neuro-Psiquiatria , 2001,
Abstract: é relatado em alguns estudos que idosos deprimidos apresentam maior frequência de hipersinais ao exame de ressonancia magnética do que controles normais. No entanto os indivíduos estudados tinham fatores de risco para doen as cerebrovasculares. Este estudo analisou pacientes com história de depress o maior e indivíduos controles compatíveis, excluindo-se fatores de risco cerebrovasculares, com o objetivo de determinar se indivíduos deprimidos apresentam maior frequência de hipersinais em substancia branca e outras les es. Avaliamos a prevalência e a severidade dos hipersinais à ressonancia magnética de encéfalo em 30 pacientes idosos deprimidos e 20 controles pareados para a idade. Hipersinais de substancia branca profunda, hipersinais periventriculares e hipersinais em substancia cinzenta subcortical foram classificados em escala padr o 0-3, por dois radiologistas que desconheciam o diagnóstico clínico. N o foram encontradas diferen as significativas entre os grupos para hipersinais subcorticais. Estes achados sugerem que os fatores de risco cerebrovasculares provavelmente medeiam a rela o entre depress o e hipersinais, encontrada em estudos anteriores.
Metais presentes no chorume coletado no aterro sanitário de Ribeir?o Preto, S?o Paulo, Brasil, e sua relevancia para saúde pública
Celere, Marina Smidt;Oliveira, Aline da Silva;Trevilato, Tania Maria Beltramini;Segura-Mu?oz, Susana Inés;
Cadernos de Saúde Pública , 2007, DOI: 10.1590/S0102-311X2007000400021
Abstract: this study analyzed the levels of cadmium, lead, copper, chromium, manganese, mercury, and zinc in leachate from the ribeir?o preto landfill site in s?o paulo state, brazil. samples were taken from runoff tanks in module i (operating from 1989 to 2000) and module ii (operating since november 2000). metal levels were measured by atomic absorption spectrophotometry at the university of s?o paulo in ribeir?o preto (university hospital). results were compared to the maximum limits for metal concentration in liquid effluents set by ruling 357/2005 of the national environmental council (conama). the study also investigated whether there was any attenuation in metal concentrations in the leachate, considering differences in the life spans of the various ribeir?o preto landfill site modules. metal levels in the samples were within the maximum limits for cadmium, chromium, copper, mercury, and manganese, but lead and zinc were above the limits set by the above-mentioned ruling.
Informatiza??o da informa??o: a experiência do Sistema de Bibliotecas da Universidade Federal do Rio Grande do Sul
Gon?alves, Eliane Maria Severo;Costa, Janise Silva Borges da;Caregnato, Laís Freitas;Fraga, Tania Marisa de Abreu;
Ciência da Informa??o , 1998, DOI: 10.1590/S0100-19651998000100014
Abstract: the library system of the federal university of rio grande do sul has been developing the ufrgs library automation system _ sabi, since 1988. this paper presents sabi, emphasizing the resources used in its definition and implementation, its structure and its application in the treatment, recovery and diffusion of bibliographic data of documents produced in the university.
Composi??o química do sedimento e de folhas das espécies do manguezal do estuário do Rio S?o Mateus, Espírito Santo, Brasil
Bernini, Elaine;Silva, Maria Amélia B. da;Carmo, Tania Mara S. do;Cuzzuol, Geraldo Rogério F.;
Brazilian Journal of Botany , 2006, DOI: 10.1590/S0100-84042006000400018
Abstract: we analyzed nutrient concentrations in leaves and sediments, and element accumulation capacity in foliar tissues of avicennia germinans (l.) stearn., avicennia schaueriana staft & leechm., laguncularia racemosa (l.) gaertn. f. and rhizophora mangle l. in four sites along the s?o mateus river estuary mangrove, espírito santo state, se-brazil. in sediment, elements decrease following the sequence: mg > ca > fe > k > mn > p > zn > cu and showed inter and intraespecific variation. avicennia leaves showed the greatest n, k and mg concentrations and lowest ca concentrations. rhizophora mangle presented the greatest mn concentration, and laguncularia racemosa the greatest fe level. sediment nutrient concentrations reflected the influence of granulometry in this compartment. nutrient accumulation in leaves varied according to species and study site but it was not correlated with sediment concentrations. results confirmed the mangrove role as a biogeochemistry barrier blocking heavy metal up to tropical coastal areas. however, it is necessary periodic sampling so that it can be possible a better understanding of the nutrient dynamic.
Spasmolytic activity of lapachol and its derivatives, α and β-lapachone, on the guinea-pig ileum involves blockade of voltage-gated calcium channels
Cavalcante, Fabiana A.;Silva, Joelmir L. V.;Carvalho, Viviane M. N.;Camara, Celso A.;Silva, Tania M. S.;Pinto, ?ngelo C.;Vargas, Maria D.;Silva, Bagnólia A.;
Revista Brasileira de Farmacognosia , 2008, DOI: 10.1590/S0102-695X2008000200007
Abstract: lapachol, α and β-lapachone are naphthoquinones extracted from species of tabebuia that have shown antiinflammatory, antibacterial, anticancer and trypanosomicidal properties. the aim of this work was to investigate the spasmolytic effect of these naphthoquinones on the guinea-pig ileum, since other naphthoquinones are known to depress the contractile activity of smooth muscles. lapachol, α and β-lapachone inhibited the phasic contractions induced by both carbachol (ic50 = 1.5 ± 0.2 x 10-4; 7.3 ± 0.9 x 10-5 and 3.2 ± 0.5 x 10-5 m, respectively) and histamine (ic50 = 3.6± 0.5; 3.6 ± 0.7 and 3.3 ± 0.6 x 10-5 m, respectively). these compounds also relaxed the ileum pre-contracted with kcl (ec50 = 1.2 ± 0.4; 4.3 ± 0.8 and 2.7 ± 0.2 x 10-5 m, respectively); carbachol (ec50 = 2.6 ± 0.7; 3.5 ± 0.5 and 2.2 ± 0.7 x 10-5 m, respectively) or histamine (ec50 = 3.0 ± 0.8; 1.1 ± 0.3 and 3.3 ± 0.6 x 10-5 m, respectively) in a concentration-dependent manner. this effect is probably due to inhibition of calcium influx through voltage-gated calcium channels (cav). β-lapachone antagonized (pd'2 = 5.73 ± 0.12; slope = 1.51 ± 0.05) cacl2-induced contractions in depolarizing medium nominally without ca2+. the finding that β-lapachone inhibited the tonic contractions induced by s-(-)-bay k8644 (ec50 = 1.4 ± 0.1 x 10-5 m) is suggestive that the l-type cav is involved. in conclusion, lapachol, α and β-lapachone showed non-selective spasmolytic activity in guinea-pig ileum, and β-lapachone exerts this effect by to blockade of l-type cav channels.
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