RESUMEN
The aggregation and accumulation of amyloid beta (Aß) peptide is believed to be the primary cause of Alzheimer's disease (AD) pathogenesis. Vitamin D-binding protein (DBP) can attenuate Aß aggregation and accumulation. A biocompatible polymer poly (D,L-lactic acid-co-glycolic acid) (PLGA) can be loaded with therapeutic agents and control the rate of their release. In the present study, a PLGA-based drug delivery system was used to examine the therapeutic effects of DBP-PLGA nanoparticles in Aß-overexpressing (5XFAD) mice. DBP was loaded into PLGA nanoparticles and the characteristics of the DBP-PLGA nanoparticles were analyzed. Using a thioflavin-T assay, we observed that DBP-PLGA nanoparticles significantly inhibited Aß aggregation in vitro. In addition, we found that intravenous injection of DBP-PLGA nanoparticles significantly attenuated the Aß accumulation, neuroinflammation, neuronal loss and cognitive dysfunction in the 5XFAD mice. Collectively, our results suggest that DBP-PLGA nanoparticles could be a promising therapeutic candidate for the treatment of AD.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Portadores de Fármacos/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Proteína de Unión a Vitamina D/administración & dosificación , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Animales , Masculino , Ratones , Ratones Transgénicos , Nanopartículas/química , Agregación Patológica de Proteínas/tratamiento farmacológico , Agregación Patológica de Proteínas/metabolismo , Agregación Patológica de Proteínas/patología , Proteína de Unión a Vitamina D/uso terapéuticoRESUMEN
The objective of the present study is to investigate the catalytic performance of mesoporous alumina that were prepared via spray pyrolysis for double bond migration from 2-butene to 1-butene. The mesoporous alumina particles were prepared via spray pyrolysis by changing the types of organic surfactants and Al precursors. The texture and acidic properties of mesoporous alumina were analyzed through N2 adsorption, SEM, ammonia-temperature programmed desorption, and FT-IR of adsorbed pyridine. The morphologies and texture properties of the mesoporous alumina were found to have been strongly influenced by the combination of the Al precursor and the structure-directing agents. The mesoporous alumina samples had two kinds of acidic sites: a Lewis acid site and a H-bonded weak acid site. 1-Butene was produced selectively through double bond migration of 2-butene over all of the mesoporous alumina catalysts. The catalyst prepared by using a chloride compound as an aluminium precursor and CTAC as a structure-directing agent showed the highest activity in the double bond migration of 2-butene, which was attributed to its large surface area and an overall high amount of acid sites.
RESUMEN
Two kinds of ordered mesoporous silicas, SBA-15 and MSU-H, have been synthesized and functionalized by direct and post synthesis method to widen their various application possibilities. In this study, phenyltrimethoxysilane (PTMS), methacryloxy-methyltrimethoxysilane (MAMTMS), 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (ECETMS), and N(beta-aminoethyl)-gamma-aminopropylmethyldimethoxysilane (AEAPMDMS) were used as a silane precursor for the functionalization. The post synthesis was more effective method to sustain ordered pore structure than the direct synthesis method under our experimental conditions. The surface area and pore size of mesoporous silica SBA-15 and MSU-H decreased through the functionalization process. FT-IR and XPS results confirmed the functionalized silane existence in the SBA-15/MAMTMS. These functional groups (vinyl, epoxide, and amine group) could be useful for various applications such as a linker of functional organic materials or active metal for heterogeneous catalysts. As a practical instance, rhodium immobilized on the aminated SBA-15 was investigated as a 1-octene hydroformylation.