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1.
Semin Cutan Med Surg ; 30(3): 176-80, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21925373

RESUMO

The skin is a complex organ and its aging is a complex process. Cutaneous aging is influenced by factors such as sun exposure, genetics, stress and the environment. While skin laxity, rhytides, and dyschromia appear on the surface, these processes originate in deeper layers including the dermis and subcutaneous tissues. Until recently, most topical skin treatments were applied to, and consequently only affected the skin surface. Skin care has evolved to be scientifically based, and as knowledge increases about the physiology of the skin, novel methods of maintaining its health and appearance are developed. New generation skin care products are targeting multiple aging mechanisms by utilizing functional active ingredients in combination with innovative delivery systems.


Assuntos
Cosméticos/administração & dosagem , Cosméticos/uso terapêutico , Sistemas de Liberação de Medicamentos , Nanotecnologia , Administração Tópica , Humanos , Lipossomos , Nanopartículas , Envelhecimento da Pele , Higiene da Pele , Adesivo Transdérmico
2.
J Control Release ; 108(1): 21-32, 2005 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-16126299

RESUMO

The production and characterization of AI-700, an intravenously administered ultrasound contrast agent under investigation for myocardial perfusion echocardiography, are described. The product consists of small, porous microparticles filled with decafluorobutane gas, and formulated as a dry powder. Small scale spray drying studies demonstrated that porous PLGA microparticles could be produced with varying porosity using ammonium bicarbonate as a volatile pore-forming agent. The porous microparticles of AI-700 were created aseptically by spray drying a water-in-oil emulsion containing poly-d,l-lactide-co-glycolide, 1,2-diarachidoyl-sn-glycero-3-phosphocholine, and ammonium bicarbonate using a two-chamber spray dryer. The porous microparticles were further formulated into a dry powder drug product (AI-700) containing decafluorobutane gas and excipients. The dry powder was reconstituted with sterile water prior to evaluation. Microscopy demonstrated that the microparticles were sphere-shaped and internally porous. The microparticles were appropriately sized for intravenous administration, having an average diameter of 2.3 mum. Zeta-potential analysis demonstrated that the microparticles would be expected to be stable post-reconstitution. The microparticles retained encapsulated gas post-reconstitution, had high acoustic potency that was stable over time and were physically stable upon exposure to high-power ultrasound, as used clinically. AI-700 has the characteristics desirable for an intravenously administered ultrasound contrast agent for myocardial perfusion echocardiography.


Assuntos
Meios de Contraste/química , Ecocardiografia , Fluorocarbonos/química , Ácido Láctico/química , Ácido Poliglicólico/química , Polímeros/química , Meios de Contraste/administração & dosagem , Composição de Medicamentos/instrumentação , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Excipientes , Fluorocarbonos/administração & dosagem , Injeções Intravenosas , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Porosidade
3.
Pharm Res ; 22(3): 347-55, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15835739

RESUMO

PURPOSE: To develop a rapidly dissolving porous particle formulation of paclitaxel without Cremophor EL that is appropriate for quick intravenous administration. METHODS: A rapidly dissolving porous particle formulation of paclitaxel (AI-850) was created using spray drying. AI-850 was compared to Taxol following intravenous administration in a rat pharmacokinetic study, a rat tissue distribution study, and a human xenograft mammary tumor (MDA-MB-435) model in nude mice. RESULTS: The volume of distribution and clearance for paclitaxel following intravenous bolus administration of AI-850 were 7-fold and 4-fold greater, respectively, than following intravenous bolus administration of Taxol. There were no significant differences between AI-850 and Taxol in tissue concentrations and tissue area under the curve (AUC) for the tissues examined. Nude mice implanted with mammary tumors showed improved tolerance of AI-850, enabling higher administrable does of paclitaxel, which resulted in improved efficacy as compared to Taxol administered at its maximum tolerated dose (MTD). CONCLUSIONS: The pharmacokinetic data indicate that paclitaxel in AI-850 has more rapid partitioning from the bloodstream into the tissue compartments than paclitaxel in Taxol. AI-850, administered as an intravenous injection, has been shown to have improved tolerance in rats and mice and improved efficacy in a tumor model in mice when compared to Taxol.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Interações Hidrofóbicas e Hidrofílicas , Paclitaxel/administração & dosagem , Animais , Química Farmacêutica , Feminino , Humanos , Infusões Intravenosas , Masculino , Camundongos , Camundongos Nus , Paclitaxel/metabolismo , Tamanho da Partícula , Porosidade , Ratos , Ratos Sprague-Dawley
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