RESUMEN
Recently, there has been increased interest in self-healing membranes containing functional microcapsules in relation to challenges involving water treatment membranes. In this study, a self-healing membrane has been prepared by incorporating microcapsules with a polyurethane (PU) shell and a diisocyanate core in a poly(ether sulfone) (PES) membrane. Depending on the characteristics of the microcapsule, to precisely quantify the self-healing behavior and performance of the produced microcapsule embedded membranes, it is important to understand the effect of a used surfactant on microcapsule synthesis. It is noteworthy that mixed surfactants have been employed to control and tailor the size and morphology of microcapsules during the synthetic process, and the surfactant system employed was one of the most dominant parameters for affecting the healing capability of microcapsule embedded membranes. Various techniques including microscopy (optical and electron), thermal analyses (DSC and TGA), and water flux measurements have been employed. This article provides essential and important information for future research into the subtle relation between microcapsule properties with varied synthetic parameters and the self-healing behavior of membrane.
RESUMEN
We developed a simple dual signal (color and 'Off-On' fluorescent change) ensemble system based on the complex between a rhodamine derivative 1 and Al(3+) for the detection of pyrophosphate (PPi) in 100% aqueous solutions. The complex between the rhodamine compound and Al(3+) was utilized as a chemosensing ensemble for the first time. The ensemble showed highly sensitive and selective fluorescent and colorimetric response to pyrophosphate among the anions in 100% aqueous solutions and no interference of the potent biological competitors including ATP, ADP, and phosphate for the detection of PPi in 100% aqueous solutions at pH 7.4.
Asunto(s)
Aluminio/química , Difosfatos/análisis , Fluorescencia , Compuestos Organometálicos/química , Rodaminas/química , Colorimetría , Soluciones , Espectrometría de Fluorescencia , Agua/químicaRESUMEN
Rice bran contains various polyphenolic compounds with anti-oxidative activities, and it has long been known to inhibit melanogenesis, but the inhibition mechanism has not been fully elucidated. Cofermentation of rice bran with Lactobacillus rhamnosus and Saccharomyces cerevisiae significantly reduced the cytotoxicity of the resulting extract to B16F1 melanoma cells. Marked reduction of alpha-melanocyte stimulating hormone (MSH) induced melanin synthesis was also observed upon treatment with fermented rice bran extract but it had no direct inhibitory effect on tyrosinase activity, while the intracellular tyrosinase activity was reduced by the extract. This result was further confirmed by an immunoblot assay measuring the level of tyrosinase protein. In addition, the expression of microphthalmia-associated transcription factor (MITF), a key regulator of melanogenesis, was significantly decreased by the extract. All together, the fermented rice bran extracts showed an inhibitory effect on melanogenesis through downregulation of MITF, along with reduced cytotoxicity.
Asunto(s)
Regulación hacia Abajo/efectos de los fármacos , Fermentación , Melaninas/biosíntesis , Melanoma/metabolismo , Factor de Transcripción Asociado a Microftalmía/metabolismo , Oryza/metabolismo , alfa-MSH/metabolismo , Animales , Línea Celular Tumoral , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Melanoma/patología , Melanosomas/efectos de los fármacos , Melanosomas/metabolismo , Ratones , Monofenol Monooxigenasa/antagonistas & inhibidores , Oryza/química , Extractos Vegetales/farmacología , Extractos Vegetales/toxicidad , alfa-MSH/antagonistas & inhibidoresRESUMEN
Among the various anions, only cyanide induced the revival of fluoresecence of -Cu(2+) resulting in "Off-On" type sensing of cyanide, which can be monitored at pH 7.4 in 100% aqueous system, and has been applied to a microfluidic platform, in which fluorescent sensor -Cu(2+) displayed green fluorescence upon the addition of cyanide, the in vivo imaging of cyanide using Caenorhabditis elegans.
Asunto(s)
Técnicas Biosensibles , Caenorhabditis elegans , Cobre/química , Cianuros/análisis , Técnicas Analíticas Microfluídicas/métodos , Contaminantes Químicos del Agua/análisis , Agua/análisis , Animales , Aniones/química , Cianuros/química , Colorantes Fluorescentes , Contaminantes Químicos del Agua/químicaRESUMEN
The application of rice wine on skin is known to have beneficial effects such as enhancement of the skin barrier function and skin whitening. In this study, we focused on examination of the anti-aging effects of rice wine. The treatment of fibroblasts with rice wine in vitro increased the expression of procollagen and laminin-5, a key basement membrane component in cultured human fibroblasts. Rice wine significantly reduced the expression of UV-induced matrix metalloproteinase-1 (MMP-1) in a dose-dependent manner in both cultured human fibroblasts and keratinocytes. In addition, treatment with rice wine decreased UV-induced tumor necrosis factor-alpha (TNF-alpha) production in human keratinocytes. An in vivo study using hairless mice showed that topical application of rice wine protected mouse skin from photoaging. Thus, we suggest that rice wine may have potential as an effective agent for the prevention and treatment of UV-induced skin aging.
Asunto(s)
Fibroblastos/efectos de los fármacos , Queratinocitos/efectos de los fármacos , Oryza , Envejecimiento de la Piel/efectos de los fármacos , Vino , Animales , Células Cultivadas , Fibroblastos/metabolismo , Fibroblastos/efectos de la radiación , Humanos , Queratinocitos/metabolismo , Queratinocitos/efectos de la radiación , Laminina/metabolismo , Metaloproteinasa 1 de la Matriz/biosíntesis , Ratones , Ratones Pelados , Procolágeno/metabolismo , Envejecimiento de la Piel/efectos de la radiación , Factor de Necrosis Tumoral alfa/metabolismo , Rayos Ultravioleta/efectos adversosRESUMEN
The effect of poly(ADP-ribosyl)ation on the stability of p53 in SK-HEP1 cells treated with UV light was examined. Intracellular levels of p53 increased in cells treated with a low dose of UV light (20 J/m2), whereas they increased but then declined after a higher dose of UV (100 J/m2). Intracellular levels of p53 in the UV treated SK-HEP1 cells were dependent on the UV dose. Use of proteasome inhibitors revealed that p53 is degraded by proteasomal proteolysis after high doses of UV light. We present evidence that, at low doses, poly(ADP-ribose)polymerase (PARP) poly(ADP-ribosyl)ates p53 and protects it from proteasomal degradation before caspase-3 is activated, whereas at high doses the cells undergo UV induced apoptosis and PARP is cleaved by caspase-3 before it can protect p53 from degradation. Destabilization of p53 by cleavage of PARP may be important in cell fate decision favoring apoptosis.
Asunto(s)
Apoptosis/fisiología , Células Cultivadas/efectos de la radiación , Poli Adenosina Difosfato Ribosa/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Caspasa 3/metabolismo , Relación Dosis-Respuesta en la Radiación , Activación Enzimática , Humanos , Poli(ADP-Ribosa) Polimerasa-1 , Poli(ADP-Ribosa) Polimerasas/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma , Proteína p53 Supresora de Tumor/genética , Rayos UltravioletaRESUMEN
von Willebrand factor (vWF) multimeric pattern and von Willebrand factor-cleaving protease activity (vWF-cp) were studied using plasmas from patients with advanced stage- and limited stage-malignant tumors. Deficiency of highly polymeric forms of vWF was observed in plasmas from 7 of 11 patients tested. vWF-cp activity was deficient in plasma samples of six patients with advanced stage-malignant tumors (ranging from 6% to 30% activity of normal plasma), whereas an essentially normal vWF-cp activity was observed in samples taken from patients with limited stage-malignant tumors. Inhibitor of vWF-cp was not detected in any plasma samples tested. To further analyze the relevance of this enzymatic activity in metastatic diagnosis, a study of vWF-cp activity was conducted in 17 patients with colon cancer, and it was shown that deficiency of vWF-cp was associated with the progression of the disease.