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Search Results: 1 - 10 of 514579 matches for " De Moura Kelly C. G. "
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Trypanocidal activity of isolated naphthoquinones from Tabebuia and some heterocyclic derivatives: a review from an interdisciplinary study
De Moura Kelly C. G.,Emery Flávio S.,Neves-Pinto Cleverson,Pinto Maria do Carmo F. R.
Journal of the Brazilian Chemical Society , 2001,
Abstract: Naphthoquinones isolated from the wood of trees of the families Bignoniaceae and Verbenaceae have been subjected to an interdisciplinary study since the seventies, when Dr. Benjamin Gilbert, at the Federal University of Rio de Janeiro, launched a program on the chemistry of natural products active against endemic diseases. In this paper we describe the synthesis of five naphthoimidazoles, derived from this program and their activity towards T. cruzi, the etiologic agent of Chagas disease. We also review the influence of chemical structure on trypanocidal action of naphthoquinones and of derived heterocycles with imidazole, oxazole, phenoxazine, indole, dipyrane and cyclopentene rings. The overall analysis corroborates the tendency of trypanocidal activity in compounds with an imidazole or oxazole ring linked to a naphthopyrane structure. Two naphthoimidazoles presented higher activities (14.5x and 34.8x) than the standard crystal violet. Emphasis is given to the biodiversity of the Brazilian flora as a starting point for the development of an autonomous and creative medicinal chemistry.
Trypanocidal activity of isolated naphthoquinones from Tabebuia and some heterocyclic derivatives: a review from an interdisciplinary study
De Moura, Kelly C. G.;Emery, Flávio S.;Neves-Pinto, Cleverson;Pinto, Maria do Carmo F. R.;Dantas, Andrea P.;Salom?o, Kelly;Castro, Solange L. de;Pinto, Ant?nio V.;
Journal of the Brazilian Chemical Society , 2001, DOI: 10.1590/S0103-50532001000300003
Abstract: naphthoquinones isolated from the wood of trees of the families bignoniaceae and verbenaceae have been subjected to an interdisciplinary study since the seventies, when dr. benjamin gilbert, at the federal university of rio de janeiro, launched a program on the chemistry of natural products active against endemic diseases. in this paper we describe the synthesis of five naphthoimidazoles, derived from this program and their activity towards t. cruzi, the etiologic agent of chagas disease. we also review the influence of chemical structure on trypanocidal action of naphthoquinones and of derived heterocycles with imidazole, oxazole, phenoxazine, indole, dipyrane and cyclopentene rings. the overall analysis corroborates the tendency of trypanocidal activity in compounds with an imidazole or oxazole ring linked to a naphthopyrane structure. two naphthoimidazoles presented higher activities (14.5x and 34.8x) than the standard crystal violet. emphasis is given to the biodiversity of the brazilian flora as a starting point for the development of an autonomous and creative medicinal chemistry.
1,4- Addition of diazomethane to a heterodiene: a direct preparation of the oxazolic ring
Emery, Flávio da S.;Silva, Raphael S.F.;Moura, Kelly C.G. de;Pinto, Maria C.F.R.;Amorim, Mauro B.;Malta, Valéria R.S.;Santos, Regina H.A.;Honório, Kátia M.;Silva, Albérico B.F. da;Pinto, Antonio V.;
Anais da Academia Brasileira de Ciências , 2007, DOI: 10.1590/S0001-37652007000100004
Abstract: the reaction of naphthoquinone-oximes (3) and (4) with diazomethane yields directly, in one step, the oxazoles (5) and (6), respectively.
Regula??o da síntese e secre??o de tireotrofina
Moura, Egberto G. de;Moura, Carmen C. Pazos de;
Arquivos Brasileiros de Endocrinologia & Metabologia , 2004, DOI: 10.1590/S0004-27302004000100006
Abstract: the set point of thyrotropin (tsh) secretion is determined by the balance of a positive regulation of thyrotropin releasing hormone (trh) and the strong negative regulation exerted by thyroid hormones. in addition, there are other regulators superimposed on this main axis such as somatostatin and dopamine, which act as inhibitors of tsh secretion, and central alpha-adrenergic pathways that are predominantly stimulatory and involved in the cold-induced thyroid activation. nutritional status and leptin also regulate tsh by stimulating trh neurons through direct and indirect mechanisms. stress is also involved in lowering trh/tsh secretion possibly through glucocorticoids, cytokines and opioids. recently, a new regulatory pathway has been proposed, via peptides produced in pituitary, acting in an autocrine/paracrine manner. among those, more consistent data are available on neuromedin b, gastrin-releasing peptide and pituitary leptin, which act as local inhibitors of tsh release. neonatal programming of tsh secretion set point is also discussed.
Efeito de métodos de irriga??o e do uso de cobertura vegetal sobre o cultivo de repolho em S?o Luís-MA
Moura, Emanoel G de;Rezende, Karla Danielle A;Araujo, Jovenilson C;Castro, Melissa F;
Horticultura Brasileira , 2006, DOI: 10.1590/S0102-05362006000400003
Abstract: in order to develop techniques that minimize heat stress of cabbage crop (brassica oleracea var. capitata l.) provoked by high air temperatures in s?o luís (ma), brazil, an experiment was carried out in a sandy alfisol. we compared irrigation by sprinkler in two daily periods of irrigation (12:00 and 18:00 hours) and with and without mulching with furrow irrigation with and without mulching in a completely randomized design with six replications. the schedule of irrigation and the use of mulch didn't affect the development of the cabbage heads in the irrigation by sprinkler treatments, as these factors didn't significantly affect the compactness, the length of the heart or the mass of the cabbage heads. by contrast, in furrow irrigation the compactness and the mass of the cabbage heads were significantly affected by mulching, the absence of mulching resulted in not very firm heads and low fresh mass (mean of 300 g), and a low productivity (7.5 mg.ha-1). the furrow irrigation in covered soil and sprinkle in covered or uncovered soil didn't allow better development of the cabbage plants.
Investigating the spontaneous formation of SDS micelle in aqueous solution using a coarse-grained force field
Pires, José Maria;Moura, André F. de;Freitas, Luiz C. G.;
Química Nova , 2012, DOI: 10.1590/S0100-40422012000500021
Abstract: a 1μs molecular dynamic simulation was performed with a realistic model system of sodium dodecyl sulfate (sds) micelles in aqueous solution, comprising of 360 ds-, 360 na+ and 90000 water particles. after 300 ns three different micellar shapes and sizes 41, 68 and 95 monomers, were observed. the process led to stabilization in the total number of sds clusters and an increase in the micellar radius to 2.23 nm, in agreement with experimental results. an important conclusion, is be aware that simulations employed in one aggregate, should be considered as a constraint. size and shape distribution must be analyzed.
Potencial pedoclimático do Estado da Bahia para o cultivo da atemóia
Silva, Thieres G. F. da;Zolnier, Sérgio;Moura, Magna S. B. de;Sediyama, Gilberto C.;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2009, DOI: 10.1590/S1415-43662009000500009
Abstract: atemoya crop has become an option for commercial purposes in the state of bahia. however, the expansion of the cultivated area is being conducted without knowledge of the climatic and pedologic crop requirements. the objective of this work was to carry out a pedoclimatic zoning for atemoya cultivation in the state of bahia based on established criteria of climate and soil according to crop requirements. by crossing the information between climatic and pedologic thematic maps, it was verified that 19.3% of the state territory exhibited appropriate conditions for crop production. marginal and unsuitable areas were also identified, covering 13.9 and 24.3% respectively of the state area. restrictions for atemoya cultivation were also observed in the major part of the territory (42.5%), which is caused mainly by climatic limitations. however, areas that present soil water deficiency only should have the cultivation encouraged by the use of irrigation since ideal conditions of the pedologic and the remaining climatic factors may be appropriate for obtaining high income.
Qualidade de Organossolo sob diferentes usos antrópicos em áreas de preserva o permanente no Distrito Federal Quality of Histosol under different on anthropic uses in permanent preservation areas in the Distrito Federal
Luciano N. de A. e Moura,Marilusa P. C. Lacerda,Maria L. G. Ramos
Revista Brasileira de Engenharia Agrícola e Ambiental , 2013,
Abstract: O uso e a ocupa o das terras devem ser planejados de forma racional a fim de evitar impactos ambientais negativos nos recursos naturais, particularmente em áreas ambientalmente protegidas por lei. O objetivo deste trabalho foi avaliar atributos de qualidade dos solos em áreas de preserva o permanente da Microbacia do Ribeir o do Gama, Distrito Federal, Brasil, para verificar o efeito do uso antrópico. Foram avaliados atributos físicos, químicos e biológicos de qualidade de organossolos em cinco áreas de uso e ocupa o diversificada das terras: três áreas cultivadas (hortali as, eucalipto e mandioca) e duas áreas preservadas (pastagem nativa e mata de galeria). As amostras de solo foram coletadas nas camadas de 0-10 e 10-20 cm. Os dados obtidos pelas análises físicas, químicas e biológicas dos solos foram avaliados estatisticamente por meio do software Sisvar 4.6. Os resultados obtidos mostraram influência dos usos e ocupa es diferentes das terras em rela o aos atributos de qualidade dos solos. O manejo dos solos adotado nessas áreas foi considerado o principal fator de altera o dos atributos físicos, químicos e biológicos, destacando-se a compacta o dos solos sob áreas de vegeta o nativa e diminui o da matéria organica nos solos em sistemas cultivados. The use and occupation of soil should be planned in a rational way to avoid negative environmental impacts on natural resources, particularly in areas environmentally protected by law. This study aimed to evaluate quality attributes of soil in permanent preservation areas of a Ribeir o do Gama Watershed, Distrito Federal, Brazil, to verify the influence of anthropic use. The physical, chemical and biological attributes of Histosol quality were assessed in five areas of diversified use and soil occupation: three areas under cultivation (vegetables, eucalyptus and cassava) and two preserved areas (native pasture and gallery forest). Soil samples were collected in 0-10 and 10-20 cm depth. The data obtained for physical, chemical and biological analysis of the soils were statistically evaluated using the Sisvar 4.6 software. The results obtained showed the influence of different uses and soil occupation in relation to the attributes of soil quality. The adopted management in these areas was considered the main factor of change in the physical, chemical and biological attributes, highlighting the compaction of soils under native vegetation and decrease of organic matter in the soils under cultivated systems.
Order and thermalized dynamics in Heisenberg-like square and Kagomé spin ices
G. M. Wysin,A. R. Pereira,W. A. Moura-Melo,C. I. L. de Araujo
Physics , 2014, DOI: 10.1088/0953-8984/27/7/076004
Abstract: Thermodynamic properties of a spin ice model on a Kagom\'e lattice are obtained from dynamic simulations and compared with properties in square lattice spin ice. The model assumes three-component Heisenberg-like dipoles of an array of planar magnetic islands situated on a Kagom\'e lattice. Ising variables are avoided. The island dipoles interact via long-range dipolar interactions and are restricted in their motion due to local shape anisotropies. We define various order parameters and obtain them and thermodynamic properties from the dynamics of the system via a Langevin equation, solved by the Heun algorithm. Generally, a slow cooling from high to low temperature does not lead to a particular state of order, even for a set of coupling parameters that gives well thermalized states and dynamics. Some suggestions are proposed for the alleviation of the geometric frustration effects and for the generation of local order in the low temperature regime.
Chromosomal organization of the 18S and 5S rRNAs and histone H3 genes in Scarabaeinae coleopterans: insights into the evolutionary dynamics of multigene families and heterochromatin
Diogo C Cabral-de-Mello, Sárah G Oliveira, Rita C de Moura, Cesar Martins
BMC Genetics , 2011, DOI: 10.1186/1471-2156-12-88
Abstract: The number of 18S rRNA gene (a member of the 45S rDNA unit) sites varied from one to 16 and were located on the autosomes, sex chromosomes or both, although two clusters were most common. Comparison of the 45S rDNA cluster number and the diploid numbers revealed a low correlation value. However, a comparison between the number of 45S rDNA sites per genome and the quantity of heterochromatin revealed (i) species presenting heterochromatin restricted to the centromeric/pericentromeric region that contained few rDNA sites and (ii) species with a high quantity of heterochromatin and a higher number of rDNA sites. In contrast to the high variability for heterochromatin and 45S rDNA cluster, the presence of two clusters (one bivalent cluster) co-located on autosomal chromosomes with the 5S rRNA and histone H3 genes was highly conserved.Our results indicate that the variability of the 45S rDNA chromosomal clusters is not associated with macro-chromosomal rearrangements but are instead related to the spread of heterochromatin. The data obtained also indicate that both heterochromatin and the 45S rDNA loci could be constrained by similar evolutionary forces regulating spreading in the distinct Scarabaeinae subfamily lineages. For the 5S rRNA and the histone H3 genes, a similar chromosomal organization could be attributed to their association/co-localization in the Scarabaeinae karyotypes. These data provide evidence that different evolutionary forces act at the heterochromatin and the 45S rDNA loci compared to the 5S rRNA and histone H3 genes during the evolution of the Scarabainae karyotypes.Repetitive DNA elements constitute a large portion of eukaryote genomes and include satellites, minisatellites, microsatellites, transposable elements and some multigene families with high copy numbers [1,2]. Among them, ribosomal RNAs (rRNA) and histone genes are grouped into distinct multigene families that are organized in tandem with hundreds to thousands of copies of each [3,4]. Th
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