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1.
Int J Pharm ; 600: 120476, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33737100

RESUMEN

Bacterial cellulose nanofibrils (BCNFs), possessing excellent biocompatibility as well as hygroscopicity, are receiving high interest as a biomaterial for biomedical and healthcare treatments, since they exert various interactions with tissues after surface modification with biochemicals such as peptides, proteins, and catechols. Herein, we report a BCNF-based skin adhesion system, wherein cell penetrating peptide (CPP)-conjugated BCNFs were employed to enhance the attraction to the skin under wet conditions. For this, we conjugated Bac7, a type of CPP, with the carboxylate of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-oxidized BCNFs. We showed that Bac7-conjugated BCNFs exhibited both hydrophobic and electrostatic interactions with the cell membrane, which eventually led to the remarkable adhesion against the skin surface. Furthermore, we demonstrated that such tailored skin attraction played a key role in improving skin water retention.


Asunto(s)
Péptidos de Penetración Celular , Nanofibras , Celulosa , Óxidos N-Cíclicos , Agua
2.
Phytother Res ; 28(7): 1088-95, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24375856

RESUMEN

Crude Panax ginseng has been documented to possess hair growth activity and is widely used to treat alopecia, but the effects of ginsenoside Rg3 on hair growth have not to our knowledge been determined. The aim of the current study was to identify the molecules through which Rg3 stimulates hair growth. The thymidine incorporation for measuring cell proliferation was determined. We used DNA microarray analysis to measure gene expression levels in dermal papilla (DP) cells upon treatment with Rg3. The mRNA and protein expression levels of vascular endothelial growth factor (VEGF) in human DP cells were measured by real-time polymerase chain reaction and immunohistochemistry, respectively. We also used immunohistochemistry assays to detect in vivo changes in VEGF and 3-stemness marker expressions in mouse hair follicles. Reverse transcription polymerase chain reaction showed dose-dependent increases in VEGF mRNA levels on treatment with Rg3. Immunohistochemical analysis showed that expression of VEGF was significantly up-regulated by Rg3 in a dose-dependent manner in human DP cells and in mouse hair follicles. In addition, the CD8 and CD34 were also up-regulated by Rg3 in the mouse hair follicles. It may be concluded that Rg3 might increase hair growth through stimulation of hair follicle stem cells and it has the potential to be used in hair growth products.


Asunto(s)
Dermis/efectos de los fármacos , Ginsenósidos/farmacología , Folículo Piloso/efectos de los fármacos , Cabello/crecimiento & desarrollo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Dermis/citología , Femenino , Folículo Piloso/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Panax/química , ARN Mensajero/metabolismo , Regulación hacia Arriba
3.
Pharm Biol ; 51(11): 1467-76, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24106757

RESUMEN

CONTEXT: Sophora flavescens Ait. (Leguminosae) has been proposed as a new whitening agent for cosmetics, because it has a strong ability to inhibit tyrosinase, a key enzyme in the formation of melanin. OBJECTIVE: We conducted a study to determine whether ethanol extract of the roots of S. flavescens has the potential for use as a whitening cosmetic agent by investigating its underlying mechanisms of action. MATERIALS AND METHODS: To elucidate the mechanism of action of S. flavescens extract, we used DNA microarray technology. We investigated the changes in the mRNA levels of genes associated with the formation and transport of melanosomes. We also identified the formation and transport of melanosomes with immunohistochemistry and immunofluorescence analyses. Finally, the skin-whitening effect in vivo of S. flavescens extract was analyzed on human skin. RESULTS: We found that S. flavescens extract strongly inhibited tyrosinase activity (IC50, 10.4 µg/mL). Results also showed that key proteins involved in the formation and transport of melanosomes were dramatically downregulated at both mRNA and protein level in keratinocytes exposed to S. flavescens extract. In addition, a clinical trial of a cream containing 0.05% S. flavescens extract on human skin showed it had a significant effect on skin whitening by mechanical and visual evaluation (1.14-fold). DISCUSSION AND CONCLUSION: This study provides important clues toward understanding the effects of S. flavescens extract on the formation and transport of melanosomes. From these results, we suggest that naturally occurring S. flavescens extract might be useful as a new whitening agent in cosmetics.


Asunto(s)
Melanosomas/efectos de los fármacos , Extractos Vegetales/farmacología , Preparaciones para Aclaramiento de la Piel/farmacología , Pigmentación de la Piel/efectos de los fármacos , Piel/efectos de los fármacos , Sophora , Adulto , Línea Celular , Técnicas de Cocultivo , Método Doble Ciego , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica , Humanos , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Melanosomas/metabolismo , Persona de Mediana Edad , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Fitoterapia , Raíces de Plantas , Plantas Medicinales , ARN Mensajero/metabolismo , Piel/metabolismo , Pigmentación de la Piel/genética , Adulto Joven
4.
J Nanosci Nanotechnol ; 13(4): 2566-72, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23763130

RESUMEN

Mesoporous SBA-15-based catalysts were applied, for the first time, to the pyrolysis of waste mandarin residue. Si-SBA-15 with few acid sites, Al-SBA-15 with a significant amount of acid sites owing to the alumination treatment, and Pt/Al-SBA-15, which was synthesized by incorporating 7.1-nm Pt nanoparticles on Al-SBA-15, were used. Pyrolysis experiments were conducted by pyrolysis gas chromatography/mass spectroscopy to determine the catalytic activities of the catalysts used. X-ray diffraction, nitrogen adsorption, NH3-temperature-programmed desorption and transmission electron microscopy were used to characterize the catalysts. Al-SBA-15 produced higher quality bio-oil than Si-SBA-15 due to its better deoxygenation and cracking performance stemming from the presence of acid sites. Pt/Al-SBA-15 showed the highest oxygenate conversion as well as the largest yield of high-value-added compounds, such as aromatics, low-molecular-mass hydrocarbons and furans.

5.
Waste Manag Res ; 31(4): 421-7, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23179512

RESUMEN

An economic evaluation of ethanol (EtOH) production from a thermo-chemical process derived from biomass/waste feedstocks was conducted. The influence of feed amounts, catalytic conversions, and EtOH selling prices was examined as these are the major variables for the economic evaluation of biomass/wastes conversion to EtOH. Among the three feedstock systems of biomass, high-moisture municipal solid waste (MSW), and plastic waste, the plastic waste has far better economic feasibility, with a payback period of 2-5 years at maximum CO conversion (40%) from syngas to ethanol, due to its higher heating value in comparison with biomass and high-moisture MSW. The heating value of the feedstock is a key factor in determining the overall economic efficiency in a thermo-chemical EtOH production system. Furthermore, enhancement of the CO conversion (related to catalytic activity) from syngas to EtOH using a low cost catalyst is necessary to retain economic efficiency because the CO conversion and cost consideration of catalyst are crucial factors to reduce the payback period.


Asunto(s)
Biomasa , Etanol/metabolismo , Catálisis , Estudios de Factibilidad
6.
Naunyn Schmiedebergs Arch Pharmacol ; 382(1): 89-101, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20508917

RESUMEN

Our previous study demonstrated the increase in the repair of UVB damage by mRg2, a mixture of ginsenosides containing 60% Rg2 in NIH3T3 cells. In the present study, the effects of purified Rg2 on the repair and apoptosis in ultraviolet B (UVB)-exposed HaCaT cells were investigated on gene expression levels. When cells were exposed to UVB and post-incubated in normal medium for 24 h, the cell viability decreased to about 50% of that in nontreated control. When Rg2 was post-incubated, however, the UVB-induced cytotoxicity was significantly prevented in an Rg2 concentration- and time-dependent manner. The apoptotic nuclear fragmentation resulting from UVB exposure was also significantly protected by the Rg2 post-incubation. Microarray analysis showed that the genes stimulated by the Rg2-alone treatment include those involved in p53 signaling pathway such as GADD45alpha, GADD45beta, and cell communication genes. RT-PCR analysis showed that the Rg2-alone treatment slightly upregulated the p53 and GADD45 transcript and protein levels by about 1.5-fold as compared with the nontreated control. The mRNA levels of p53 and GADD45 in cells exposed to UVB and post-incubated with Rg2 for 24 h decreased in an Rg2 concentration-dependent manner as compared with that post-incubated in normal medium. However, the mRNA level of the UVB-exposed cells post-incubated with 5 microM retinol was essentially the same as that post-incubated in normal medium. Time course experiment showed that the mRNA levels of p53 and GADD45 in UVB-exposed cells were upregulated by post-incubation with 50 microM Rg2 until 6 and 9 h, respectively, and then gradually decreased until 24 h. By Western blot analysis, it was also revealed that the Rg2 post-incubation decreases the expression of p53, phospho-p53, GADD45, and ATM in UVB-exposed cells. Time course analysis also indicated that these decreased expressions were due to the earlier upregulation of p53 and GADD45 proteins. When UVB-exposed cells were post-incubated with Rg2 for 24 h after UVB exposure, the level of remaining cyclobutane pyrimidine dimers decreased in both Rg2 concentration- and time-dependent manner. All these results suggest that Rg2 protects cells against UVB-induced genotoxicity by increasing DNA repair, in possible association with modulation of protein levels involved in p53 signaling pathway.


Asunto(s)
Daño del ADN/efectos de los fármacos , Ginsenósidos/farmacología , Queratinocitos/efectos de los fármacos , Rayos Ultravioleta/efectos adversos , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Células Cultivadas , Reparación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/efectos de la radiación , Ginsenósidos/administración & dosificación , Humanos , Queratinocitos/efectos de la radiación , Análisis por Micromatrices , ARN Mensajero/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Proteína p53 Supresora de Tumor/metabolismo
7.
Waste Manag ; 27(2): 168-76, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-16513339

RESUMEN

Pyrolysis of a waste plastic mixture (high-density polyethylene: low-density polyethylene: polypropylene: polystyrene = 3:2:3:1) into a liquid product was carried out in a stirred semi-batch reactor at low (350 degrees C) and high (400 degrees C) temperatures. The effect of lapse time of reaction in the reactor and also degradation temperature on the characteristics of the liquid product from pyrolysis of the mixture was investigated. Liquid products were described by cumulative amount distribution, paraffin, olefin, naphthene and aromatic (PONA) distribution and molecular weight distribution. Their characteristic was quite differed with a lapse time of reaction and also at a low and high degradation temperatures, because of the different physicochemical properties of the plastic types in the mixture. With increase of lapse time of reaction, the order for the main products in PONA components obtained at 350 degrees C was firstly aromatic products and then olefin products, while at 400 degrees C the order was firstly aromatic products, then olefin products and finally paraffin products. The experiments also showed from the molecular weight distribution of liquid PONA components that the paraffin and olefin products had a wide distribution by mainly random scission of polymer, but in the case of olefin products were produced by an end-chain scission mechanism as well as random scission mechanism, as evidenced by much more light olefin products. This phenomenon was evident at a higher degradation temperature. Also, both the light olefin and naphthene products with a molecular weight of around 120, as a main product, showed a similar trend as a function of lapse time, which had a maximum fraction at 343 min (at 350 degrees C) and 83 min (at 400 degrees C). Among PONA components, the highest concentrations of aromatic products were obtained with a molecular weight of around 100 at the fastest lapse time of reaction, regardless of degradation temperature. It was concluded that the characteristics of liquid product on the pyrolysis of plastic mixtures were strongly influenced by lapse time of reaction and degradation temperature.


Asunto(s)
Calor , Incineración , Plásticos , Residuos , Factores de Tiempo , Residuos/análisis
8.
Laryngoscope ; 116(7): 1180-4, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16826057

RESUMEN

OBJECTIVES: The objective of this study was to investigate how the expression of the RANK-RANKL-OPG system mediates the formation and differentiation of osteoclasts and causes bone resorption in cholesteatoma. METHODS: An immunohistochemical analysis was carried out in 22 cholesteatoma tissues obtained during middle ear surgery and 15 normal postauricular skin tissues to examine the expression of RANKL and OPG. RESULTS: All 22 cases of cholesteatoma and the 15 cases of normal postauricular skin expressed RANKL and OPG. The count and rate of RANKL-positive cells in cholesteatoma was significantly higher than in normal postauricular skin. The count and rate of OPG-positive cells in normal postauricular skin was significantly higher than in cholesteatoma. The ratio of the positive expression rates of RANKL and OPG in cholesteatoma was statistically higher than in normal postauricular skin. CONCLUSIONS: We provide evidence suggesting that RANKL, which activates osteoclasts, plays a significant role in the mechanism of bone destruction in cholesteatoma, and that the ratio of RANKL to OPG may be a reliable indicator of bone destruction in cholesteatoma.


Asunto(s)
Proteínas Portadoras/biosíntesis , Colesteatoma del Oído Medio/metabolismo , Glicoproteínas/biosíntesis , Glicoproteínas de Membrana/biosíntesis , Osteoclastos/metabolismo , Receptores Citoplasmáticos y Nucleares/biosíntesis , Receptores del Factor de Necrosis Tumoral/biosíntesis , Biomarcadores/metabolismo , Colesteatoma del Oído Medio/patología , Progresión de la Enfermedad , Humanos , Inmunohistoquímica , Técnicas In Vitro , Osteoclastos/patología , Osteoprotegerina , Pronóstico , Ligando RANK , Receptor Activador del Factor Nuclear kappa-B , Estudios Retrospectivos
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