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1.
Pharmaceutics ; 16(5)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38794280

RESUMO

Silybin (SIB) is a hepatoprotective drug known for its poor oral bioavailability, attributed to its classification as a class IV drug with significant metabolism during the first-pass effect. This study explored the potential of solid lipid nanoparticles with (SLN-SIB-U) or without (SLN-SIB) ursodeoxycholic acid and polymeric nanoparticles (PN-SIB) as delivery systems for SIB. The efficacy of these nanosystems was assessed through in vitro studies using the GRX and Caco-2 cell lines for permeability and proliferation assays, respectively, as well as in vivo experiments employing a murine model of Schistosomiasis mansoni infection in BALB/c mice. The mean diameter and encapsulation efficiency of the nanosystems were as follows: SLN-SIB (252.8 ± 4.4 nm, 90.28 ± 2.2%), SLN-SIB-U (252.9 ± 14.4 nm, 77.05 ± 2.8%), and PN-SIB (241.8 ± 4.1 nm, 98.0 ± 0.2%). In the proliferation assay with the GRX cell line, SLN-SIB and SLN-SIB-U exhibited inhibitory effects of 43.09 ± 5.74% and 38.78 ± 3.78%, respectively, compared to PN-SIB, which showed no inhibitory effect. Moreover, SLN-SIB-U demonstrated a greater apparent permeability coefficient (25.82 ± 2.2) than PN-SIB (20.76 ± 0.1), which was twice as high as that of SLN-SIB (11.32 ± 4.6) and pure SIB (11.28 ± 0.2). These findings suggest that solid lipid nanosystems hold promise for further in vivo investigations. In the murine model of acute-phase Schistosomiasis mansoni infection, both SLN-SIB and SLN-SIB-U displayed hepatoprotective effects, as evidenced by lower alanine amino transferase values (22.89 ± 1.6 and 23.93 ± 2.4 U/L, respectively) than those in control groups I (29.55 ± 0.7 U/L) and I+SIB (34.29 ± 0.3 U/L). Among the prepared nanosystems, SLN-SIB-U emerges as a promising candidate for enhancing the pharmacokinetic properties of SIB.

2.
Carbohydr Polym ; 207: 601-608, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30600045

RESUMO

Cashew gum (CG) is a biopolymer that presents a favorable chemical environment for structural modifications, which leads to more stable and resistant colloidal systems. The gum was subjected to an acetylation reaction using a fast, simple, solvent-free and low cost methodology. The derivative was characterized by infrared and NMR spectroscopy, elemental analysis, coefficient of solubility and zeta potential. The modified biopolymer was used as a platform for drug delivery systems using insulin as a model drug. Nanoparticles were developed through the technique of polyelectrolytic complexation and were characterized by size, surface charge, entrapment efficiency and gastrointestinal release profile. The nanoparticles presented size of 460 nm with a 52.5% efficiency of entrapment of insulin and the electrostatic stabilization was suggested by the zeta potential of + 30.6 mV. Sustained release of insulin was observed for up to 24 h. The results showed that acetylated cashew gum (ACG) presented potential as a vehicle for sustained oral insulin release.


Assuntos
Anacardium/química , Sistemas de Liberação de Medicamentos , Insulina/administração & dosagem , Nanopartículas/química , Gomas Vegetais/química , Acetilação , Administração Oral , Química Verde/métodos , Tamanho da Partícula , Gomas Vegetais/síntese química
4.
Nanomedicine ; 10(6): 1139-51, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24632248

RESUMO

Nanodelivery systems have been extensively studied as a strategy for the effective treatment of type 1 diabetes in animal models. Nanoparticle formulations have been shown to contribute to increased intestinal absorption of insulin according to established pathways. It is important to determine whether intestinal absorption of the hormone, specifically occurs through a privileged pathway that is favored because of particular properties of the nanoparticles. Confocal fluorescence microscopy has revealed that nanoparticles-based oral insulin delivery in intestinal tissues causes their accumulation in Peyer's patches. To quantify the preponderance of M cells involved in the overall absorption of insulin in the intestine, in vitro and in vivo results of insulin-loaded nanoparticles were analyzed and criticized based on the utilized method and whether it has translational impact for the treatment of diabetes in humans. The degree of insulin nanoparticles uptake will be interpreted for its effectiveness in the prevention/treatment of other pathologies. FROM THE CLINICAL EDITOR: This study investigates nano-formulation based insulin delivery through the oral route, with particular attention to their accumulation in Peyer patches and the role of M-cells in their absorption. While oral delivery of insulin would be an important step from the standpoint of convenience, accurate dosing and issues of potential toxicity need to be considered before clinical translation of this method.


Assuntos
Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Insulina/administração & dosagem , Insulina/farmacocinética , Absorção Intestinal , Mucosa Intestinal/citologia , Nanopartículas/metabolismo , Administração Oral , Animais , Portadores de Fármacos/metabolismo , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Mucosa Intestinal/metabolismo , Nódulos Linfáticos Agregados/citologia , Nódulos Linfáticos Agregados/metabolismo
5.
J Pharm Sci ; 102(11): 4057-64, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23983168

RESUMO

The treatment of benign prostatic hyperplasia can be accomplished by the use of different drugs including, doxazosin, an α-1 adrenergic antagonist, and finasteride (FIN), a 5-α reductase inhibitor. Traditionally, treatments using these drugs have been administered as either a mono or combination therapy by the oral route. A transdermal delivery system optimized for doxazosin and FIN combination therapy would provide increased patient adherence and facilitate dose adjustment. Doxazosin base (DB) was prepared from doxazosin mesylate and characterized together with FIN, by X-ray powder diffraction (XRD), differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR). The permeation enhancers, azone and lauric acid, and the gelling agents, hydroxypropyl cellulose (HPC) and Poloxamer 407 (P407), were evaluated to determine their ability to promote in vitro permeation of drugs through the pig ear epidermis. Successful preparation of DB was confirmed by evaluating the XRD, DSC, and NMR patterns and in vitro studies revealed that 3% (w/w) azone was the best permeation enhancer. When P407 gel was compared with HPC gel, it showed reduced lag time and promoted higher permeation of both drugs. This may be because of the interactions of the former with the stratum corneum, which disorganizes the lipid structure and consequently promotes higher drug permeation.


Assuntos
Inibidores de 5-alfa Redutase/administração & dosagem , Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Doxazossina/administração & dosagem , Finasterida/administração & dosagem , Veículos Farmacêuticos/metabolismo , Inibidores de 5-alfa Redutase/farmacocinética , Administração Cutânea , Antagonistas de Receptores Adrenérgicos alfa 1/farmacocinética , Animais , Azepinas/metabolismo , Doxazossina/farmacocinética , Finasterida/farmacocinética , Humanos , Ácidos Láuricos/metabolismo , Masculino , Permeabilidade , Hiperplasia Prostática/tratamento farmacológico , Absorção Cutânea , Suínos
6.
Rio de Janeiro; s.n; 2004. 108 p. tab, graf.
Tese em Português | LILACS | ID: lil-402073

RESUMO

O presente trabalho propõe a elaboração de um sistema que, reunindo possíveis instrumentos existentes, tem como objetivo acompanhar os projetos de Pesquisas do Centro de Informação Científica e Tecnológica, de modo a permitir análises permanentes, vinculadas às demandas de C&T em saúde, que levem em consideração os contextos sociossanitário e científico-tecnológico.O instrumento a ser proposto deverá ter consonância com as prioridades institucionais no campo da pesquisa na área da Informação e Comunicação em Saúde. Ele permitirá o redirecionamento de propostas de acordo com as demandas sociais, adequando as atividades do planejamento e permitindo ao CICT ter um controle em tempo real de seus projetos. Isso fornecerá subsídios para apoiar com maior eficiência, eficácia e efetividade o desenvolvimento científico, através da disponibilização de insumos e infra-estrutura básicos, planejando melhor os recursos orçamentários, financeiros e humanos e também atenderá com maior amplitude aos anseios do quadro de pesquisa da Unidade.


Assuntos
Projetos de Pesquisa
7.
Rev. chil. neurocir ; 6(10): 66-8, 1992. ilus
Artigo em Português | LILACS | ID: lil-138008

RESUMO

A case of traumatic occlusion of the middle cerebral artery in a 12 years-old child is reporter. This complication has been rarely observed, since cerebral angiography was substituted by computed tomography in patients with head injury in emergency rooms. The mechanisms involved in the physiopathology of this complication and its treatment are discussed


Assuntos
Criança , Arteriopatias Oclusivas/fisiopatologia , Artérias Cerebrais/lesões , Traumatismos Craniocerebrais/fisiopatologia , Arteriopatias Oclusivas/diagnóstico , Arteriopatias Oclusivas/tratamento farmacológico , Estudos de Casos e Controles , Tomografia Computadorizada por Raios X
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