Universidade Federal Rural do Rio de Janeiro

About: Universidade Federal Rural do Rio de Janeiro is a education organization based out in Seropédica, Brazil. It is known for research contribution in the topics: Population & Species richness. The organization has 6405 authors who have published 9852 publications receiving 105911 citations.

Características físico-químicas da carne de bubalinos e de bovinos castrados e inteiros

Abstract: As caracteristicas fisico-quimicas da carne de bovinos Nelore (NE), F1 Nelore x Sindi (NS) e de bufalos Mediterrâneos (BM) castrados e inteiros foram avaliadas. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 3 x 2 (tres grupos geneticos x duas condicoes sexuais) com 24 parcelas. Os animais foram confinados, receberam a mesma dieta e foram abatidos com media de 437,5 kg. As amostras de carne foram obtidas do musculo Longissimus dorsi entre a 11a e 12a costelas. A carne de animais inteiros ofereceu maior teor de umidade (73,6 vs 71,0%), de proteina (87,5 vs 78,6%) e de minerais (4,33 vs 3,85%) e menor teor de gordura (8,9 vs 16,8%) que castrados. A carne de bovinos NE teve maior teor de gordura (15,4%) que NS (12,5%) e BM (10,8%), nao havendo diferenca para a condicao sexual dentro do grupo de BM. A luminosidade, intensidade do vermelho e intensidade do amarelo da carne e da gordura foram semelhantes entre NE, NS e BM, enquanto os castrados alcancaram maior luminosidade (39,0 vs 37,2) e intensidade do amarelo (1,82 vs 0,87) que inteiros, mas a intensidade do vermelho da carne e a luminosidade, intensidade do vermelho e intensidade do amarelo da gordura foram semelhantes entre grupos geneticos e condicao sexual. A carne de BM apresentou menor forca de cisalhamento (3,75 kgf) que NS (4,85 kgf) e NE (5,9 kgf), bem como dos castrados (4,5 kgf) em relacao aos inteiros (5,2 kgf), mas nao houve diferenca entre grupo genetico e condicao sexual para perda por cozimento e para pH final. A carne de bufalos e animais inteiros apresentou menor teor de gordura, sem perder o valor nutritivo, maciez e a baixa perda por cozimento.

Cytotoxic and DNA-topoisomerase effects of lapachol amine derivatives and interactions with DNA

Abstract: The cytotoxic activity of amino (3a-e), aza-1-antraquinone (4a-e) lapachol derivatives against Ehrlich carcinoma and human K562 leukemia cells was investigated. Cell viability was determined using MTT assay, after 48 (Ehrlich) or 96 h (K562) of culture, and vincristine (for K562 leukemia) and quercetin (for Ehrlich carcinoma) were used as positive controls. The results showed dose-dependent growthinhibiting activities and that the amino derivatives were active against the assayed cells, whereas the 4a-e derivatives were not. The allylamine derivative 3a was the most active against Ehrlich carcinoma, with IC50 = 16.94 ± 1.25 µM, and against K562 leukemia, with IC50 = 14.11 ± 1.39 µM. The analogous lawsone derivative, 5a, was also active against Ehrlich carcinoma (IC50 = 23.89 ± 2.3 µM), although the 5d and 5e derivatives showed lower activity. The interaction between 3a-d and calf thymus DNA was investigated by fluorimetric titration and the results showed a hyperchromic effect indicating binding to DNA as presented of ethidium bromide, used as positive control. The inhibitory action on DNA-topoisomerase II-α was also evaluated by a relaxation assay of supercoiled DNA plasmid, and the etoposide (200 µM) was used as positive control. Significant inhibitory activities were observed for 3a-d at 200 µM and a partial inhibitory action was observed for lapachol and methoxylapachol.

Características básicas para um agrupamento ecológico preliminar de espécies madeireiras da floresta de terra firme da Amazônia Central

Abstract: The aim of this study was to gather information on timber trees occurring in a non-flooded forest near Manaus and to makean attempt to rank these species according to their succession in the forest. The ranking would be helpful in modeling theforest’s dynamics, for forest conservation, management and rehabilitation of degraded areas. The group studied was formedby 60 botanical species belonging to 42 genera and 18 families. In a general view, seed size was >0.5cm3 (69% of the species),seed dispersal by animals predominated (60%), germination occurred within a period of up to 3 months (69%) and wooddensity was high (>0.8 g/cm3 in 52%). However the set of characteristics did not permit a clear ranking of all species, ascharacteristics thought to be typical for pioneer or climax occurred together on the same species in 24 of the selected trees(40%). Wood density and fruiting regularity showed to be of little use for classification, as well as the presence of seeddormancy, as dormancy was detected in all successional groups. On the other hand, a distinction between the various typesof seed dormancy was helpful to separate the groups. The following seed related characteristics may be recommended forclassification: dispersal type, reserve quantity, desiccation tolerance and dormancy types. The attempt of ranking the timberspecies according to their role in natural succession showed that most had a set of characteristics typical of mature forest.Only a few species had earlier successional characteristics, and probably have higher resistance to forest disturbance.