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1.
Nat Mater ; 16(3): 342-348, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27918565

RESUMO

The fabrication of oriented, crystalline films of metal-organic frameworks (MOFs) is a critical step toward their application to advanced technologies such as optics, microelectronics, microfluidics and sensing. However, the direct synthesis of MOF films with controlled crystalline orientation remains a significant challenge. Here we report a one-step approach, carried out under mild conditions, that exploits heteroepitaxial growth for the rapid fabrication of oriented polycrystalline MOF films on the centimetre scale. Our methodology employs crystalline copper hydroxide as a substrate and yields MOF films with oriented pore channels on scales that primarily depend on the dimensions of the substrate. To demonstrate that an anisotropic crystalline morphology can translate to a functional property, we assembled a centimetre-scale MOF film in the presence of a dye and showed that the optical response could be switched 'ON' or 'OFF' by simply rotating the film.


Assuntos
Estruturas Metalorgânicas/química , Anisotropia , Compostos Inorgânicos/química , Modelos Moleculares , Conformação Molecular , Nanotubos/química , Porosidade
2.
ACS Appl Mater Interfaces ; 6(21): 19355-9, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25296395

RESUMO

Water vapor barriers are important in various application fields, such as food packaging and sealants in electronic devices. Polymer/clay composites are well-studied water vapor barrier materials, but their transparency and mechanical strength degrade with increasing clay loading. Herein, we demonstrate films with good water vapor barrier properties, high transparency, and mechanical/thermal stability. Water vapor barrier films were prepared by the solution crystallization of siloxane hybrid lamellae. The films consist of highly crystallized organic/inorganic hybrid lamellae, which provide high transparency, hardness, and thermal stability and inhibit the permeation of water vapor. The water permeability of a 6 µm thick hybrid film is comparable to that of a 200 µm thick silicon rubber film.

3.
BMC Complement Altern Med ; 12: 101, 2012 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-22809229

RESUMO

BACKGROUND: Extracts of Sasa senanensis Rehder are used in traditional Japanese medicine; however, little is known about the underlying mechanisms of their potential health benefits. METHODS: S. senanensis leaves were extracted with subcritical water. An active small-molecule was isolated using reversed-phase high-performance liquid chromatography (HPLC), and identified as 3,4-dihydroxybenzaldehyde (protocatechuic aldehyde or PA). The effects of PA on the activity of histone demethylase, the Drosophila melanogaster lifespan and gene expression in Drosophila S2 cells were investigated. RESULTS: PA inhibited the activity of Jumonji domain-containing protein 2A (JMJD2A) histone demethylase in a dose-dependent manner with a half-maximal inhibitory concentration (IC50) of 11.6 µM. However, there was no effect on lysine-specific demethylase 1 (LSD1), histone deacetylase 1 (HDAC1) or HDAC8. PA significantly extended the lifespan of female, but not male, Drosophila. In Drosophila S2 cells, the eukaryotic translation initiation factor 4E binding protein (4E-BP) was up-regulated by PA exposure. CONCLUSIONS: Our findings provide insight into the possible relationship between the pharmacological modulation of histone demethylation and lifespan extension by PA; they might also be important in the development of alternative therapies for age-related disorders.


Assuntos
Benzaldeídos/farmacologia , Catecóis/farmacologia , Drosophila melanogaster/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Histona Desmetilases/antagonistas & inibidores , Extratos Vegetais/farmacologia , Sasa/química , Animais , Benzaldeídos/química , Benzaldeídos/isolamento & purificação , Catecóis/química , Catecóis/isolamento & purificação , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Feminino , Expressão Gênica/efeitos dos fármacos , Histona Desmetilases/química , Humanos , Expectativa de Vida , Masculino , Modelos Animais , Modelos Moleculares , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Especificidade da Espécie
5.
J Neuroophthalmol ; 26(1): 11-7, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16518160

RESUMO

A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders.


Assuntos
Infarto Cerebral/complicações , Imagem de Difusão por Ressonância Magnética/métodos , Hemianopsia/diagnóstico , Córtex Visual/irrigação sanguínea , Campos Visuais , Idoso , Infarto Cerebral/diagnóstico , Seguimentos , Hemianopsia/etiologia , Hemianopsia/fisiopatologia , Humanos , Masculino , Remissão Espontânea , Testes de Campo Visual
6.
Parasitol Int ; 55 Suppl: S289-91, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16376139

RESUMO

Japan has been one of the very few countries that operated the nationwide control programme against soil-transmitted helminths (STH) infections and gained a great success. On the basis of researches and operational studies, periodical mass-examination using cellophane thick smear (Kato technique) and selective mass-treatment targeted at school children were employed as the most useful control measure. In later years, Japan's experience and the strategy for STH control programme were transferred to Asian countries through Asian Parasite Control Organization (APCO) and also to countries of Asia, Africa and Latin-America through seminar at a modified form of the integration programme (IP) of STH control with family planning and nutritional improvement. The parasitologists group conducted studies in all aspects to seek effective STH control measures for respective countries and obtained many successful results.


Assuntos
Anti-Helmínticos/uso terapêutico , Helmintíase/prevenção & controle , Helmintíase/parasitologia , Solo/parasitologia , Adolescente , Ancylostomatoidea , Animais , Anti-Helmínticos/administração & dosagem , Ascaris lumbricoides , Criança , Pré-Escolar , Helmintíase/epidemiologia , Humanos , Lactente , Recém-Nascido , Programas Nacionais de Saúde , Trichuris
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