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1.
Phys Chem Chem Phys ; 16(34): 18226-32, 2014 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-25055242

RESUMO

The catalyzed solution-liquid-solid (SLS) growth has been well developed to synthesize semiconductor nanowires with controlled diameters. The SLS growth occurs in the longitudinal direction of nanowires, due to the directional anisotropy driven by the metal catalysts where chemical precursors are introduced. In the present study, we report a selective, template-free, and environmentally-friendly electrochemical flow-based solution-solid (electrochemical flow-SS) growth of the Cu2O nanorod array. The anisotropy for directional growth without any catalysts is generated by the electrical field in a flowing electrolyte of ultra-dilute CuSO4. The filamentary anisotropy originates from electric field enhancement on pyramidal nanocrystals in the electrolyte of low ionic conductivity (13 µS cm(-1)). The Cu2O and Cu nanorods are able to be selectively synthesized by controlling the electrolyte pH and oxygen dissolution into the electrolyte. The synthesized Cu2O nanorod array shows excellent electrochemical properties as an anode material for lithium-ion batteries; the specific capacities increase from 323 to 1206 mA h g(-1) during 500 cycles. The capacity enhancement is due to the phase transformation from Cu2O to CuO, nano-restructuring of nanorods into fragmented nanoparticles, and the progressive generation of an electroactive polymeric gel-like layer on the surface of the nanoparticles. The electrochemical flow-SS growth of Cu2O nanorods is expected to contribute to further development of other functional nanorods.

3.
Pharmaceutics ; 13(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34575544

RESUMO

Lidocaine, a commonly used local anesthetic, has recently been developed into a number of ointment products to treat hemorrhoids. This study examined its efficient delivery to the dermis through the pharmaceutical improvement of hemorrhoid treatment ointments. We attempted to increase the amount of skin deposition of lidocaine by forming a nanoemulsion through the self-nanoemulsifying effect that occurs when glycerol monostearate (GMS) is saturated with water. Using Raman mapping, the depth of penetration of lidocaine was visualized and confirmed, and the local anesthetic effect was evaluated via an in vivo tail-flick test. Evaluation of the physicochemical properties confirmed that lidocaine was amorphous and evenly dispersed in the ointment. The in vitro dissolution test confirmed that the nanoemulsifying effect of GMS accelerated the release of the drug from the ointment. At a specific concentration of GMS, lidocaine penetrated deeper into the dermis; the in vitro permeation test showed similar results. When compared with reference product A in the tail-flick test, the L5 and L6 compounds containing GMS had a significantly higher anesthetic effect. Altogether, the self-nanoemulsifying effect of GMS accelerated the release of lidocaine from the ointment. The compound with 5% GMS, the lowest concentration that saturated the dermis, was deemed most appropriate.

4.
PLoS One ; 12(11): e0187154, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29117187

RESUMO

The attenuating effects of green tea supplements (GTS) against the ultraviolet (UV) radiation induced skin damages are distinguished. However, the concomitant effects of GTS on the large intestinal microbiomes and associated metabolomes are largely unclear. Herein, we performed an integrated microbiome-metabolome analysis to uncover the esoteric links between gut microbiome and exo/endogenous metabolome maneuvered in the large intestine of UVB-exposed mice subjected to dietary GTS. In UVB-exposed mice groups (UVB), class Bacilli and order Bifidobacteriales were observed as discriminant taxa with decreased lysophospholipid levels compared to the unexposed mice groups subjected to normal diet (NOR). Conversely, in GTS fed UVB-exposed mice (U+GTS), the gut-microbiome diversity was greatly enhanced with enrichment in the classes, Clostridia and Erysipelotrichia, as well as genera, Allobaculum and Lachnoclostridium. Additionally, the gut endogenous metabolomes changed with an increase in amino acids, fatty acids, lipids, and bile acids contents coupled with a decrease in nucleobases and carbohydrate levels. The altered metabolomes exhibited high correlations with GTS enriched intestinal microflora. Intriguingly, the various conjugates of green tea catechins viz., sulfated, glucuronided, and methylated ones including their exogenous derivatives were detected from large intestinal contents and liver samples. Hence, we conjecture that the metabolic conversions for the molecular components in GTS strongly influenced the gut micro-environment in UVB-exposed mice groups, ergo modulate their gut-microbiome as well as exo/endogenous metabolomes.


Assuntos
Microbioma Gastrointestinal/efeitos da radiação , Metaboloma/efeitos da radiação , Chá/química , Raios Ultravioleta , Animais , Peso Corporal/efeitos da radiação , Catequina/análise , Dieta , Suplementos Nutricionais , Ingestão de Alimentos/efeitos da radiação , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Intestino Grosso/metabolismo , Intestino Grosso/microbiologia , Intestino Grosso/efeitos da radiação , Fígado/metabolismo , Redes e Vias Metabólicas/efeitos da radiação , Camundongos
5.
Arch Dermatol Res ; 307(3): 229-38, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25663088

RESUMO

ß-Lapachone is an ortho naphthoquinone obtained from the bark of the lapacho tree (Tabebuia avellanedae), which has been used medicinally for centuries. The purpose of this study was to investigate the effects of ß-lapachone on inhibitory mechanism of melanogenesis. ß-Lapachone inhibited melanin synthesis and tyrosinase activity at 0.8 µM in melan-a cells. Also, ß-lapachone reduced the expression of tyrosinase and tyrosinase-related protein-1 at transcriptional and translational levels. The decreased expression of tyrosinase and tyrosinase-related protein-1 might result from the reduced microphthalmia-associated transcription factor (MITF) level which regulates major melanogenic proteins. The reduced level of MITF was associated with delayed ERK activation by ß-lapachone. Furthermore, ß-lapachone reduced melanogenesis in the human 3D skin tissue culture; besides, it dramatically inhibited body pigmentation of zebrafish and decreased melanin content and tyrosinase activity. These results show that ß-lapachone may be useful as a potential depigmentation agent for various hyperpigmentation disorders.


Assuntos
Melanócitos/efeitos dos fármacos , Naftoquinonas/farmacologia , Fitoterapia/métodos , Pele/efeitos dos fármacos , Tabebuia/imunologia , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Transformada , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Melaninas/metabolismo , Melanócitos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Técnicas de Cultura de Órgãos , Oxirredutases/genética , Oxirredutases/metabolismo , Pigmentação/efeitos dos fármacos , Casca de Planta , Pele/patologia , Peixe-Zebra
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