RESUMO
Nanotechnology is an emerging field with many promising applications in drug delivery systems. Because of outstanding developments in this field, rapidly increasing research is directed to the development of nanocarriers that may enhance the availability of drugs to the target sites. Substantial fraction of information has been added into the existing scientific literature focusing on the fact that nanoparticles usually generate reactive oxygen species to a greater extent than micro-sized particles. It is worth mentioning that oxidative stress regulates an array of cell signaling cascades that resulted in cancer cell damage. Accumulating experimental evidence over the years has shown that wide-ranging biological mechanisms are triggered by these NPs in cultured cells due to the unique properties of engineered nanoparticles. In this review, we have attempted to provide an overview of the signaling cascades that are activated by oxidative stress in cancer cells in response to different kinds of nanomaterials, including quantum dots, metallic and polymeric nanoparticles.
Assuntos
Nanopartículas/efeitos adversos , Neoplasias/patologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Humanos , Neoplasias/induzido quimicamenteRESUMO
A simple, fast, sensitive and selective solid-phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) method for the quantitative analysis of ampicillin (CAS 69-53-4) in human plasma was developed using amoxicillin as internal standard, and sample extraction by solid-phase extraction (SPE). Extracts were separated by reversed-phase C18 with aqueous mobile phase (acetonitrile, 80:20, v/v) with 0.1% formic acid. The method was validated and successfully applied in a bioequivalence study of capsules 500 mg of ampicillin. Using a short running time of 2.5 min, the lower limit of quantification (LLOQ) for obtained ampicillin was 0.1 microg/ml for a plasma sample of 250 microl and a recovery of 94.38% +/- 4.05. Bioequivalence between the products was determined by calculating 90% confidence intervals (CI) for the ratio of Cmax, AUC0-t and AUC0-inf values for the test and reference products, which were within the 0.80-1.25 interval proposed by FDA and EMEA. It is concluded that the two formulations are bioequivalent in their rate and extent of absorption, and thus, may be used interchangeably.
Assuntos
Ampicilina/sangue , Ampicilina/farmacocinética , Antibacterianos/sangue , Antibacterianos/farmacocinética , Adolescente , Adulto , Amoxicilina/sangue , Calibragem , Cromatografia Líquida , Estudos Cross-Over , Método Duplo-Cego , Humanos , Indicadores e Reagentes , Masculino , Controle de Qualidade , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Equivalência TerapêuticaRESUMO
Avaliaram-se as características físicas e físico-químicas de diferentes lotes de quatro especialidades farmacêuticas contendo ibuprofeno (produtos A, B, C e D), sob a forma de comprimidos de liberação imediata, disponíveis no mercado nacional e comercializados como similares intercambiáveis, enfatizando-se o estudo comparativo da cinética de dissolução do fármaco. Utilizou-se equipamento para dissolução de formas sólidas de acordo com a USP 23, empregando-se tampão fosfato pH 7,2 como meio de dissolução a 37,0 ñ 0,5 ºC e aparato 1 na velocidade de 150 rpm. Os produtos A e B e os produtos C e D, respectivamente, poderiam, teoricamente, ser considerados equivalentes farmacêuticos, segundo a definição da Food and Drug Administration (FDA-USA)...