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1.
Nat Mater ; 19(2): 212-217, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31712744

RESUMO

The digital fabrication of oxide glasses by three-dimensional (3D) printing represents a major paradigm shift in the way glasses are designed and manufactured, opening opportunities to explore functionalities inaccessible by current technologies. The few enticing examples of 3D printed glasses are limited in their chemical compositions and suffer from the low resolution achievable with particle-based or molten glass technologies. Here, we report a digital light-processing 3D printing platform that exploits the photopolymerization-induced phase separation of hybrid resins to create glass parts with complex shapes, high spatial resolutions and multi-oxide chemical compositions. Analogously to conventional porous glass fabrication methods, we exploit phase separation phenomena to fabricate complex glass parts displaying light-controlled multiscale porosity and dense multicomponent transparent glasses with arbitrary geometry using a desktop printer. Because most functional properties of glasses emerge from their transparency and multicomponent nature, this 3D printing platform may be useful for distinct technologies, sciences and arts.

2.
Nat Commun ; 9(1): 4763, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30420659

RESUMO

Current methods for generating liquid-liquid interfaces with either controlled composition or coverage often rely on adsorption equilibria which limits the freedom to design such multiphase materials, in particular when different components are used. Moreover, when interfaces become densely populated, slowing down of adsorption may impose additional constraints. Up to now, it is not possible to control surface coverage and composition of droplet interfaces at will. Here, we report a generic and versatile method to create designer liquid-liquid interfaces, using transient double emulsions. We demonstrate how the surface coverage in Pickering emulsions can be controlled at will, even for dense particulate layers going up to multilayers. Moreover, composite droplet interfaces with compositional control can be generated, even with particles which would have intrinsically different or even opposite adsorption characteristics. Given its simplicity, this method offers a general approach for control of composition of liquid-liquid interfaces in a variety of multiphase systems.

3.
Langmuir ; 33(36): 9007-9017, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28813598

RESUMO

Microcapsules with organic-inorganic hybrid shells can be used as functionally responsive delivery systems that are attractive for a broad range of applications. Hybrid-shell microcapsules have often been synthesized by the assembly of solid inorganic nanoparticles and polymers. Efforts to extend this approach to microfluidic emulsification have been hampered by problems with clogging and flow instabilities when utilizing dispersions of solid particles. In this work, hybrid shell microcapsules are synthesized through the reaction of liquid precursors, eliminating the use of solid dispersions. Our microfluidic water-oil-water emulsification technique also enables the preparation of hybrid-shell microcapsules with thicker and more robust shells compared to alternative techniques. By utilizing bridged-silane precursors to form the hybrid material, we demonstrate hybrid-shell microcapsules with independently tunable functional and mechanical/barrier properties. This independent tuning of physical and functional properties allows for the production of functional organic-inorganic hybrid shell microcapsules that can be tailored to meet the demands of a wide range of applications.

4.
Mitochondrion ; 36: 36-42, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28093355

RESUMO

Leber hereditary optic neuropathy (LHON) is an important cause of mitochondrial blindness among young adults. In this study, we investigated the potential of four quinone analogues (CoQ1, CoQ10, decylubiquinone and idebenone) in compensating for the deleterious effect of the m.11778G>A mitochondrial DNA mutation. The LHON fibroblast cell lines tested exhibited reduced cell growth, impaired mitochondrial bioenergetics and elevated levels of reactive oxygen species (ROS). Idebenone increased ATP production and reduced ROS levels, but the effect was partial and cell-specific. The remaining quinone analogues had variable effects and a negative impact on certain mitochondrial parameters was observed in some cell lines.


Assuntos
Trifosfato de Adenosina/biossíntese , Antioxidantes/metabolismo , Fibroblastos/efeitos dos fármacos , Atrofia Óptica Hereditária de Leber/patologia , Quinonas/metabolismo , Espécies Reativas de Oxigênio/análise , Ubiquinona/análogos & derivados , Adolescente , Células Cultivadas , Metabolismo Energético/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Ubiquinona/metabolismo , Adulto Jovem
5.
Brain ; 137(Pt 8): 2329-45, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24934289

RESUMO

Mitochondrial DNA instability disorders are responsible for a large clinical spectrum, among which amyotrophic lateral sclerosis-like symptoms and frontotemporal dementia are extremely rare. We report a large family with a late-onset phenotype including motor neuron disease, cognitive decline resembling frontotemporal dementia, cerebellar ataxia and myopathy. In all patients, muscle biopsy showed ragged-red and cytochrome c oxidase-negative fibres with combined respiratory chain deficiency and abnormal assembly of complex V. The multiple mitochondrial DNA deletions found in skeletal muscle revealed a mitochondrial DNA instability disorder. Patient fibroblasts present with respiratory chain deficiency, mitochondrial ultrastructural alterations and fragmentation of the mitochondrial network. Interestingly, expression of matrix-targeted photoactivatable GFP showed that mitochondrial fusion was not inhibited in patient fibroblasts. Using whole-exome sequencing we identified a missense mutation (c.176C>T; p.Ser59Leu) in the CHCHD10 gene that encodes a coiled-coil helix coiled-coil helix protein, whose function is unknown. We show that CHCHD10 is a mitochondrial protein located in the intermembrane space and enriched at cristae junctions. Overexpression of a CHCHD10 mutant allele in HeLa cells led to fragmentation of the mitochondrial network and ultrastructural major abnormalities including loss, disorganization and dilatation of cristae. The observation of a frontotemporal dementia-amyotrophic lateral sclerosis phenotype in a mitochondrial disease led us to analyse CHCHD10 in a cohort of 21 families with pathologically proven frontotemporal dementia-amyotrophic lateral sclerosis. We identified the same missense p.Ser59Leu mutation in one of these families. This work opens a novel field to explore the pathogenesis of the frontotemporal dementia-amyotrophic lateral sclerosis clinical spectrum by showing that mitochondrial disease may be at the origin of some of these phenotypes.


Assuntos
Esclerose Lateral Amiotrófica/etiologia , DNA Mitocondrial/genética , Demência Frontotemporal/etiologia , Mitocôndrias/patologia , Doenças Mitocondriais/complicações , Proteínas Mitocondriais/genética , Idade de Início , Idoso , Alelos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/fisiopatologia , Exoma/genética , Feminino , Demência Frontotemporal/genética , Demência Frontotemporal/fisiopatologia , Células HeLa , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/genética , Doenças Mitocondriais/genética , Mutação de Sentido Incorreto , Linhagem , Fenótipo
6.
Autism ; 12(3): 261-74, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18445735

RESUMO

It is widely accepted that autistic children experience difficulties in processing and recognizing emotions. Most relevant studies have explored the perception of faces. However, context and bodily gestures are also sources from which we derive emotional meanings. We tested 23 autistic children and 23 typically developing control children on their ability to recognize point-light displays of a person's actions, subjective states and emotions. In a control task, children had to recognize point-light displays of everyday objects. The children with autism only differed from the control children in their ability to name the emotional point-light displays. This suggests that children with autism can extract complex meanings from bodily movements but may be less sensitive to higher-order emotional information conveyed by human movement. The results are discussed in the context of a specific deficit in emotion perception in children with autism.


Assuntos
Transtorno Autístico/diagnóstico , Percepção de Movimento , Adolescente , Transtorno Autístico/psicologia , Criança , Formação de Conceito , Aprendizagem por Discriminação , Emoções , Feminino , Humanos , Masculino , Teoria da Construção Pessoal , Semântica
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