Dimensionality reduction and prediction of the protein macromolecule dissolution profile

A suitable regression model for predicting the dissolution profile of Poly (lactic-co-glycolic acid) (PLGA) micro-and nanoparticles can play a significant role in pharmaceutical/medical applications. The rate of dissolution of proteins is influenced by several factors and taking all such influencing factors into account; we have a dataset in hand with three hundred input features. Therefore, a primary approach before identifying a regression model is to reduce the dimensionality of the dataset at hand. On the one hand, we have adopted Backward Elimination Feature selection techniques for an exhaustive analysis of the predictability of each combination of features. On the other hand, several linear and non-linear feature extraction methods are used in order to extract a new set of features out of the available dataset. A comprehensive experimental analysis for the selection or extraction of features and identification of the corresponding prediction model is offered. The designed experiment and prediction models offer substantially better performance over the earlier proposed prediction models in literature for the said problem

Histologia hepática e produção em tanques-rede de tilápia-do-nilo masculinizada hormonalmente ou não masculinizada

O objetivo deste trabalho foi avaliar o desempenho e a sanidade da estrutura hepática de tilápia-do-nilo, masculinizada hormonalmente ou não masculinizada, criada em tanques-rede com dois níveis proteicos. Tilápias-do-nilo da linhagem Tailandesa (total de 2.400), com peso médio inicial de 127 g, foram distribuídas em delineamento inteiramente casualizado, com quatro tratamentos, em arranjo fatorial 2×2, correspondente aos grupos de tilápias masculinizadas hormonalmente ou não masculinizadas e ao teor proteico na dieta de 28 ou 32% de proteína bruta, com três repetições. Após 115 dias de alimentação, não houve interação entre os fatores quanto a peso final, ganho de peso, conversão alimentar, comprimento final e sobrevivência. Não houve diferença entre os peixes masculinizados hormonalmente e os não masculinizados, quanto a peso final, ganho de peso e sobrevivência, o que mostra a possibilidade de sua produção em tanques-rede, sem a necessidade de masculinização hormonal. A proteína bruta a 32% na dieta possibita melhor desempenho para ambos os grupos. Alterações histológicas no fígado - como o incremento do volume das células, o desarranjo da disposição cordonal e o aumento de vesículas nos hepatócitos - são encontradas nos peixes masculinizados hormonalmente e são mais acentuadas nos peixes alimentados com 32% de proteína bruta na dieta

Validation of high-performance liquid chromatographic method for analysis of fluconazole in microemulsions and liquid crystals

In recent decades, there has been a significant increase in the incidence of fungal diseases. Certain fungal diseases cause cutaneous lesions and in the usual treatment, generally administred orally, the drug reaches the site of action with difficulty and its concentration is too low. An approach much explored in recent years is the development of nanotechnology-based drug delivery systems, and microemulsions (ME) and liquid crystals (LC) are promising. ME and LC were developed with oleic acid or copaiba oil as the oil phase, propoxyl (5OP) ethoxyl (20 OE) cetyl alcohol as surfactant and water. An analytical method to assess the incorporation of fluconazole (FLU) in the systems under study was validated according to guidelines of the International Conference on Harmonization (ICH) guidelines and the Brazilian Food, Drug and Sanitation Agency (ANVISA). The method was conducted on a C18-RP column (250 × 4.6 mm i.d.), maintained at room temperature. The mobile phase consisted of acetonitrile and water (50:50, v/v), run at a flow rate of 1.0mL/min and using ultraviolet detection at 210nm. The chromatographic separation was obtained with a retention time of 6.3min, and was linear in the range of 20-400 µg/mL (r2=0.9999). The specificity showed no interference of the excipients. The accuracy was 100.76%. The limits of detection and quantitation were 0.057 and 0.172 µg.mL-1, respectively. Moreover, method validation demonstrated satisfactory results for precision and robustness. The proposed method was applied for the analysis of the incorporation of FLU in ME and LC, contributing to improve the quality control and to assure the therapeutic efficacy