RESUMEN

Introducing two-dimensional post arrays and a water-soluble sacrificial layer between an ultrathin substrate and a handling substrate provides controllability of the interfacial adhesion in a stable manner. The periodically anchored and suspended configuration after the chemical etching process facilitates the development of, for example, printable Alq3 -based OLEDs that can be attached to unconventional surfaces.

RESUMEN

Although the induction of heme oxygenase-1 (HO-1) by hydrogen peroxide (H2O2) has been reported, the HO-1 and odontoblastic differentiation-inducing effects against H2O2 have not been clarified in human pulp cells. In this study, we investigated whether HO-1 is involved in the protective mechanisms against the cytotoxic effects of H2O2 by using a cell viability assay, and we examined the production of dentin sialophosphoprotein (DSPP) and other mineralization markers by using reverse transcriptase-polymerase chain reaction in human pulp cells. H2O2 decreased cell viability but increased HO-1 and DSPP expression in a concentration- and time-dependent manner. Antioxidants and inhibitors of HO-1, phosphatidylinositol-3'-kinase, extracellular signal-regulated kinase, and p38 mitogen-activated protein kinase blocked H2O2-induced cytotoxicity and the expression of HO-1 and DSPP mRNA in pulp cells. These data suggest that the induction of HO-1 by H2O2 in pulp cells plays a protective role against the cytotoxic effects of H2O2 and stimulates DSPP expression, resulting in premature odontoblast differentiation through pathways that involve phosphatidylinositol-3'-kinase, p38, and extracellular signal-regulated kinase.

Asunto(s)

Pulpa Dental/efectos de los fármacos , Proteínas de la Matriz Extracelular/biosíntesis , Hemo-Oxigenasa 1/fisiología , Peróxido de Hidrógeno/toxicidad , Oxidantes/toxicidad , Western Blotting , Diferenciación Celular , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Citoprotección , Pulpa Dental/citología , Pulpa Dental/metabolismo , Hemo-Oxigenasa 1/biosíntesis , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Odontoblastos/citología , Estrés Oxidativo , Fosfoproteínas/biosíntesis , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sialoglicoproteínas , Blanqueamiento de Dientes/efectos adversos

RESUMEN

Perylenetetracarboxylic diimide (PDI) derivatives bearing two or four peripheral pyrrole pendants (PDI-nPy, n=2 or 4) are cross-linkable materials by electro/phototreatment. In this paper, we introduce a new posttreatment technique to produce an insoluble film. Unlike the common solution-phase electrochemical deposition, we first spin-coated PDI-nPy on an electrode and then electrotreated the coated surface in a monomer-free electrolyte solution. This method gives the film a smooth surface with no granules, while the common method induces a rough film with a lot of granules. The post electrochemical treatment also provides a merit of higher resolution in a patterning process on a specific metal electrode. As one of the applications, we carried out an electrochromic study on the posttreated PDI-4Py film. It turned purple (lambdamax=590 nm) and sky blue (lambdamax=797 nm) at 0 and -1.9 V vs Ag/Ag+, respectively. We believe this method will broaden the patterning concept with the desired film morphology and resolution using PDI on a specific electrode.

Asunto(s)

Imidas/química , Perileno/análogos & derivados , Electroquímica , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Estructura Molecular , Perileno/química , Análisis Espectral

RESUMEN

Perylenetetracarboxylic diimide derivatives bearing 2- or 4-peripheral pyrrole pendants could be efficiently crosslinked to form an insoluble film either by electropolymerization or visible light induced oxidative photopolymerization of the pyrrole units.