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1.
Materials (Basel) ; 12(3)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717201

RESUMO

To achieve enhanced surface characteristics in wire electrical discharge machining (WEDM), the present work reports the use of an artificial neural network (ANN) combined with a genetic algorithm (GA) for the correlation and optimization of WEDM process parameters. The parameters considered are the discharge current, voltage, pulse-on time, and pulse-off time, while the response is fractal dimension. The usefulness of fractal dimension to characterize a machined surface lies in the fact that it is independent of the resolution of the instrument or length scales. Experiments were carried out based on a rotatable central composite design. A feed-forward ANN architecture trained using the Levenberg-Marquardt (L-M) back-propagation algorithm has been used to model the complex relationship between WEDM process parameters and fractal dimension. After several trials, 4-3-3-1 neural network architecture has been found to predict the fractal dimension with reasonable accuracy, having an overall R-value of 0.97. Furthermore, the genetic algorithm (GA) has been used to predict the optimal combination of machining parameters to achieve a higher fractal dimension. The predicted optimal condition is seen to be in close agreement with experimental results. Scanning electron micrography of the machined surface reveals that the combined ANN-GA method can significantly improve the surface texture produced from WEDM by reducing the formation of re-solidified globules.

2.
Int J Biol Macromol ; 88: 236-43, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27032489

RESUMO

The intention of the study was to evaluate the effectiveness of nanocapsulated food constituent capsaicin in protection of liver oxidative stress. We had prepared phospholipid vesicle (nanoliposome) by formation of thin lipid film followed by hydration when the mean vesicle diameter was found to be 277.7nm. Protection from sodium fluoride (NaF) induced oxidative stress by capsaicin loaded nanoliposomal formulation were tested in rats where a single dose of capsaicin in free and nanoliposome forms were administered after two hour of exposure to NaF. Membrane in hepatic cells were damaged by NaF and it was evaluated by estimating reactive oxygen species (ROS), lipid peroxidation, and catalase activity when it was observed that free capsaicin produced mild protection whereas liposomal capsaicin exerted a significant result. This can be suggested that liposome encapsulating capsaicin acts as a promising therapeutic agent in reducing liver oxidative stress produced by different stress factors.


Assuntos
Antioxidantes/farmacologia , Capsaicina/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Lipossomos/química , Fígado/efeitos dos fármacos , Animais , Antioxidantes/química , Capsaicina/química , Catalase/metabolismo , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Composição de Medicamentos , Glutationa/agonistas , Glutationa/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Lipossomos/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Fluoreto de Sódio , Superóxido Dismutase/metabolismo
3.
Curr Drug Deliv ; 13(1): 27-39, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26036845

RESUMO

Cancer is the major cause of fatality and the number of new cases is increasing incessantly. Conventional therapies and existing anticancer agents cause serious side effects and expand the patient's lifespan by a few years. There is the need to exploit alternative anticancer agents and novel drug delivery system to deliver these agents to the tumor site for the prevention of cancer. Recently, biologically active compounds isolated from plants used for the management of cancer have been the heart of interest. Capsaicin is a major pungent agent present in the chili peppers that is heavily consumed in the world. Capsaicin has demonstrated effectiveness as an anticancer agent, but a restraining factor is its pungency, extremely low aqueous solubility, and poor oral bioavailability which impede its use as an anticancer agent. Many technologies have been developed and applied to conquer this drawback. We bring to light the benefits of this phytoconstituent for treating different types of cancer. We also discussed some of the delivery approaches that have already made an impact by either delivering a drug to target tissue or increasing its bioavailability by many folds.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/farmacocinética , Disponibilidade Biológica , Capsaicina/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Humanos , Solubilidade
4.
Indian J Pharmacol ; 47(6): 657-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26729959

RESUMO

AIM: Despite having better tolerability and a wide range of clinical applications over other antidepressants, selective serotonin reuptake inhibitors (SSRIs) are also known to be associated with serious adverse effects like suicidal ideation on chronic use. The present study had explored the impact of the chronic use of sertraline, an SSRI, on the behavioral changes in Wistar albino rats. MATERIALS AND METHODS: The study was conducted on 30 Wistar albino rats of either sex; divided into five groups. Four groups were subjected to chronic mild stress induced by using various stressors randomly scheduled in a week and continued for a period of 3 weeks. The stressed rodents were subjected to sertraline treatment for 9 weeks in different human therapeutic doses extrapolated to animal doses. Behavioral changes were monitored, assessed, and evaluated throughout the treatment phase with the help of tests such as locomotor activity test, forced swim test, tail suspension test, antianxiety test, and sucrose preference test (SPT). RESULTS: All tests except SPT, demonstrated significant (P < 0.05) reduction in depressive-like activity in the stressed rodents by the mid-treatment phase, followed by an abrupt onset of the depressive state by the end of the treatment phase. SPT showed a significant (P < 0.05) increase in sucrose consumption throughout the treatment phase. CONCLUSION: Behavioral changes following chronic sertraline administration conferred gradual remission of depression state on initial treatment phase, followed by a reversal of effect on chronic use.


Assuntos
Antidepressivos/administração & dosagem , Depressão/tratamento farmacológico , Modelos Animais de Doenças , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Sertralina/administração & dosagem , Animais , Antidepressivos/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Depressão/etiologia , Tolerância a Medicamentos , Comportamento Exploratório/efeitos dos fármacos , Feminino , Preferências Alimentares/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Ratos Wistar , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Sertralina/uso terapêutico , Estresse Fisiológico , Estresse Psicológico/fisiopatologia , Fatores de Tempo
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