2 resultados para Aminoácidos aromáticos

em Repositorio Institucional da UFLA (RIUFLA)


Relevância:

10.00% 10.00%

Publicador:

Resumo:

With the emergence of new genetic lines due to intense breeding improvement on swine production in recent years, there is the need to adapt more accurately diets for the current sows, which have higher nutritional demands. The use of functional amino acids aimsto optimize the sows production and among these amino acids arginine has excelled. Arginine is involved in several important metabolic pathways, for example, it serves as a substrate forsynthesis of protein, creatine, nitric oxide, polyamines, citrulline, agmatine, ornithine, proline, and glutamate. It also helps to stimulate the secretion of some hormones such as insulin, prolactin, and growth hormone.As arginine plays such important roles, its supplementation has been suggested in lactation feed once it may enhance the development of the mammary gland and milk nutritional profile, thus, providing a better piglet development.Thus, the objective was to evaluate the effect of lactation feed supplementation with L-Arginine on the productive performance of primiparoussows and their respective litter.One hundred forty sows from the same genetic lineage on a commercial farm, located in the city of Oliveira, MG were used in this study, in a completely randomized design with five treatments: control diet without amino acid supplementation and four diets with increasing levels of L-Arginine supplementation (containing 98.5% purity) - 0.5, 1.0, 1.5, and 2.0%. Each treatment hadtwenty-eight swine sows, and the experimental unit was the sowand its litter.It was used ‘on top’ amino acid supplementation.All data was submitted to variance analysis using the SAEG Software: version 9.1 (SAEG, 2005).The data relating to days of lactation were compared by Tukey test (5%). L-Arginine supplementation levels in lactation feed did not influence (P>0.05) average daily feed intake, body condition variables, and blood parameters of the sows (urea, creatinine, and non-esterified fatty acids) as well as it did not affect the dry matter, crude protein, and amino acid profile of milk and the litter performance. There was effect (P<0.05) of days of lactation on the percentage of crude protein and amino acids in milk, which reduced througout the days of lactation. The L-Arginine supplementation on the lactation diet at levels of 0.5, 1.0, 1.5, and 2.0% did not influence the sow and its respective litter performance.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Multivariate image analysis applied to the quantitative structure-activity relationships (MIA-QSAR) is a 2D QSAR technique that has been presenting promising outcomes for the development of new drug candidates, due to its simplicity, rapidity and low cost. In this way, the present study aims at introducing, consolidating and improving the new dimensions named aug-MIA-QSAR and aug-MIA-QSARcolor, as well as applying them to the study of neglected diseases, in order to obtain new drug targets using chemico-biological interpretation of the MIA molecular descriptors. Four compound data sets with experimental bioactivities against Chagas disease, malaria, dengue and schistosomiasis were evaluated using three approaches: MIA-QSARt, aug-MIA-QSAR and aug-MIA-QSARcolor. In general, representations of atoms as spheres with different colors and sizes proportional to the corresponding van der Waals radii (aug-MIA approaches) improved the predictive ability and interpretability in all data sets. The use of colors proportional to the Pauling´s electronegativity showed that MIA descriptors are capable of identifying periodic properties relevant for the studied activity. Finally, solid colors instead of spotlighted atoms allowed a correct identification of atoms by means of pixel values in the studies for malaria, dengue and schistosomiasis, which were, subsequently, useful for the chemical interpretation related to the bioactivity. It can be inferred that semicarbazones and thiosemicarbazones derivative with a tri-substituted ring in R1 group and a trifluoro methyl group in the R 3 position instead of a chlorine antitripanossoma resulted in higher activity. The antimalarial activity of quinolon-4(1H)imines can be improved if: 1) R1 and R2 are electron donor groups, 2) R3 has long aminoalkyl chains, and 3) R4 possesses substituents with big atomic volume. In the study for dengue, it was found that tetrapeptides with unbranched small size amino acids in the A1 and A4 positions can increase the substrate affinity (Km) to the NS3 protein, and when in A1 and A2 positions, the substrate cleavage rate (kcat). On the other hand, acidic amino acids in the A2 and A4 positions were found to be related with low substrate affinity to the NS3 protein and when present in A1, with low substrate cleavage rate. Finally, the presence of metoxy substituents in R1 (or R2) and R5 in the neolignan backbone can favor their antischistosomal activity.