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1.
Int J Mol Sci ; 23(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35008948

RESUMO

Myotonic dystrophy type 1 (DM1) is a hereditary and multisystemic disease characterized by myotonia, progressive distal muscle weakness and atrophy. The molecular mechanisms underlying this disease are still poorly characterized, although there are some hypotheses that envisage to explain the multisystemic features observed in DM1. An emergent hypothesis is that nuclear envelope (NE) dysfunction may contribute to muscular dystrophies, particularly to DM1. Therefore, the main objective of the present study was to evaluate the nuclear profile of DM1 patient-derived and control fibroblasts and to determine the protein levels and subcellular distribution of relevant NE proteins in these cell lines. Our results demonstrated that DM1 patient-derived fibroblasts exhibited altered intracellular protein levels of lamin A/C, LAP1, SUN1, nesprin-1 and nesprin-2 when compared with the control fibroblasts. In addition, the results showed an altered location of these NE proteins accompanied by the presence of nuclear deformations (blebs, lobes and/or invaginations) and an increased number of nuclear inclusions. Regarding the nuclear profile, DM1 patient-derived fibroblasts had a larger nuclear area and a higher number of deformed nuclei and micronuclei than control-derived fibroblasts. These results reinforce the evidence that NE dysfunction is a highly relevant pathological characteristic observed in DM1.


Assuntos
Biomarcadores , Fibroblastos/metabolismo , Membrana Nuclear/metabolismo , Núcleo Celular/metabolismo , Imunofluorescência , Humanos , Espaço Intracelular/metabolismo , Lamina Tipo A/metabolismo , Proteínas de Membrana/metabolismo , Distrofia Miotônica/genética , Distrofia Miotônica/metabolismo , Miotonina Proteína Quinase/metabolismo , Proteínas Nucleares/metabolismo
2.
Nanotechnology ; 26(13): 135202, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25760231

RESUMO

The intense light scattered from metal nanoparticles sustaining surface plasmons makes them attractive for light trapping in photovoltaic applications. However, a strong resonant response from nanoparticle ensembles can only be obtained if the particles have monodisperse physical properties. Presently, the chemical synthesis of colloidal nanoparticles is the method that produces the highest monodispersion in geometry and material quality, with the added benefits of being low-temperature, low-cost, easily scalable and of allowing control of the surface coverage of the deposited particles. In this paper, novel plasmonic back-reflector structures were developed using spherical gold colloids with appropriate dimensions for pronounced far-field scattering. The plasmonic back reflectors are incorporated in the rear contact of thin film n-i-p nanocrystalline silicon solar cells to boost their photocurrent generation via optical path length enhancement inside the silicon layer. The quantum efficiency spectra of the devices revealed a remarkable broadband enhancement, resulting from both light scattering from the metal nanoparticles and improved light incoupling caused by the hemispherical corrugations at the cells' front surface formed from the deposition of material over the spherically shaped colloids.

3.
Opt Express ; 22 Suppl 4: A1059-70, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24978069

RESUMO

Plasmonic light trapping in thin film silicon solar cells is a promising route to achieve high efficiency with reduced volumes of semiconductor material. In this paper, we study the enhancement in the opto-electronic performance of thin a-Si:H solar cells due to the light scattering effects of plasmonic back reflectors (PBRs), composed of self-assembled silver nanoparticles (NPs), incorporated on the cells' rear contact. The optical properties of the PBRs are investigated according to the morphology of the NPs, which can be tuned by the fabrication parameters. By analyzing sets of solar cells built on distinct PBRs we show that the photocurrent enhancement achieved in the a-Si:H light trapping window (600 - 800 nm) stays in linear relation with the PBRs diffuse reflection. The best-performing PBRs allow a pronounced broadband photocurrent enhancement in the cells which is attributed not only to the plasmon-assisted light scattering from the NPs but also to the front surface texture originated from the conformal growth of the cell material over the particles. As a result, remarkably high values of J(sc) and V(oc) are achieved in comparison to those previously reported in the literature for the same type of devices.

4.
Sci Technol Adv Mater ; 14(4): 045009, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27877602

RESUMO

We report the effect of a disperse carbon interlayer between the n-a-Si:H layer and an aluminium zinc oxide (AZO) back contact on the performance of amorphous silicon solar cells. Carbon was incorporated to the AZO film as revealed by x-ray photoelectron spectroscopy and energy-dispersive x-ray analysis. Solar cells fabricated on glass substrates using AZO in the back contact performed better when a disperse carbon interlayer was present in their structure. They exhibited an initial efficiency of 11%, open-circuit voltage Voc = 1.6 V, short-circuit current JSC = 11 mA cm-2 and a filling factor of 63%, that is, a 10% increase in the JSC and 20% increase in the efficiency compared to a standard solar cell.

5.
Nanomaterials (Basel) ; 13(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36616119

RESUMO

The present contribution aims to enhance solar cells' performance via the development of advanced luminescent down-shifting based on encapsulated nanostructured perovskite materials. Here, thin films of inorganic lead halide (CsPbBr3) perovskite nanocrystal luminophores were synthetized, by hot-injection, deposited on glass substrates by spin-coating, and encapsulated with parylene type C, via chemical vapor deposition, to protect and stabilize the films. The optical properties of these thin films were characterized by absorption, emission and 2D contour spectra, their structure by X-ray diffraction and X-ray photoelectron spectroscopy, and the morphology by Scanning Transmission Electron microscopy. I-V curve and spectral response nanocrystalline silicon photovoltaic (nc-Si:H PV) cells were studied in the absence and presence of the perovskite and parylene luminescent down-shifting layers. The incorporation of the CsPbBr3 nanocrystals and their encapsulation with the parylene type C polymeric coating led to an increase in the current generated and the spectral response of the PV cells in the regime of the nanocrystals' fluorescence emission. A 3.1% increase in the short circuit current density and a 5.6% increase in the power conversion efficiency were observed.

6.
Neuromuscul Disord ; 32(2): 99-115, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35031191

RESUMO

Measurement of muscle strength is fundamental for the management of patients with myotonic dystrophy type 1 (DM1). Nevertheless, guidance on this topic is somewhat limited due to heterogeneous outcome measures used. This systematic literature review aimed to summarize the most frequent outcome measures to assess muscle strength in patients with DM1. We searched on Pubmed, Web of Science and Embase databases. Observational studies using measures of muscle strength assessment in adult patients with DM1 were included. From a total of 80 included studies, 24 measured cardiac, 45 skeletal and 23 respiratory muscle strength. The most common method and outcome measures used to assess cardiac muscle strength were echocardiography and ejection fraction, for skeletal muscle strength were quantitative muscle test, manual muscle test and maximum isometric torque and medical research council and for respiratory muscle strength were manometry and maximal inspiratory and expiratory pressure. We successfully gathered the more consensual methods and measures to evaluate muscle strength in future clinical studies, particularly to test muscle strength response to treatments in patients with DM1. Future consensus on a set of measures to evaluate muscle strength (core outcome set), is important for these patients.


Assuntos
Distrofia Miotônica , Adulto , Humanos , Força Muscular/fisiologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Distrofia Miotônica/terapia , Avaliação de Resultados em Cuidados de Saúde , Torque
7.
Artigo em Inglês | MEDLINE | ID: mdl-33673200

RESUMO

Myotonic dystrophy type 1 (DM1) is an autosomal dominant hereditary and multisystemic disease, characterized by progressive distal muscle weakness and myotonia. Despite huge efforts, the pathophysiological mechanisms underlying DM1 remain elusive. In this review, the metabolic alterations observed in patients with DM1 and their connection with lipin proteins are discussed. We start by briefly describing the epidemiology, the physiopathological and systemic features of DM1. The molecular mechanisms proposed for DM1 are explored and summarized. An overview of metabolic syndrome, dyslipidemia, and the summary of metabolic alterations observed in patients with DM1 are presented. Patients with DM1 present clinical evidence of metabolic alterations, namely increased levels of triacylglycerol and low-density lipoprotein, increased insulin and glucose levels, increased abdominal obesity, and low levels of high-density lipoprotein. These metabolic alterations may be associated with lipins, which are phosphatidate phosphatase enzymes that regulates the triacylglycerol levels, phospholipids, lipid signaling pathways, and are transcriptional co-activators. Furthermore, lipins are also important for autophagy, inflammasome activation and lipoproteins synthesis. We demonstrate the association of lipin with the metabolic alterations in patients with DM1, which supports further clinical studies and a proper exploration of lipin proteins as therapeutic targets for metabolic syndrome, which is important for controlling many diseases including DM1.


Assuntos
Distrofia Miotônica , Humanos , Lipídeos , Debilidade Muscular , Compostos Orgânicos
8.
Artigo em Inglês | MEDLINE | ID: mdl-33917301

RESUMO

Myotonic dystrophy type 1 (DM1) is a hereditary disease characterized by progressive distal muscle weakness and myotonia. Patients with DM1 have abnormal lipid metabolism and a high propensity to develop a metabolic syndrome in comparison to the general population. It follows that metabolome evaluation in these patients is crucial and may contribute to a better characterization and discrimination between DM1 disease phenotypes and severities. Several experimental approaches are possible to carry out such an analysis; among them is Fourier-transform infrared spectroscopy (FTIR) which evaluates metabolic profiles by categorizing samples through their biochemical composition. In this study, FTIR spectra were acquired and analyzed using multivariate analysis (Principal Component Analysis) using skin DM1 patient-derived fibroblasts and controls. The results obtained showed a clear discrimination between both DM1-derived fibroblasts with different CTG repeat length and with the age of disease onset; this was evident given the distinct metabolic profiles obtained for the two groups. Discrimination could be attributed mainly to the altered lipid metabolism and proteins in the 1800-1500 cm-1 region. These results suggest that FTIR spectroscopy is a valuable tool to discriminate both DM1-derived fibroblasts with different CTG length and age of onset and to study the metabolomic profile of patients with DM1.


Assuntos
Distrofia Miotônica , Humanos , Debilidade Muscular , Distrofia Miotônica/diagnóstico , Distrofia Miotônica/genética , Fenótipo , Projetos Piloto , Espectroscopia de Infravermelho com Transformada de Fourier
9.
J Endod ; 42(7): 1131-4, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27233582

RESUMO

INTRODUCTION: The purpose of this study was to measure the temperature rise on the external root surface of filled root canals using Touch'n Heat (Analytic Endodontics, Orange, CA), the TC System (TC; Tanaka de Castro & Minatel Ltda, Cascavel, PR, Brazil), and the Tagger technique. METHODS: Forty-five single-canal mandibular premolar human teeth were used in the 3 experimental groups. The root canals were enlarged to accommodate up to an R40 Reciproc file (VDW, Munich, Germany). Next, the specimens were filled according to the technique evaluated. The measurement of the temperature was performed by K chromium-aluminum thermocouples attached to the coronal, middle, and apical root levels. RESULTS: There was a significant difference among the 3 techniques (P < .001) in relation to the temperature variation between the highest temperature and the initial temperature. The highest temperature change was found with the Tagger technique at the middle third root level (11.8°C), and the lowest variation was in TC at the cervical third (2.05°C). CONCLUSIONS: There was a rise of temperature on the external root surface for all of the techniques evaluated. TC showed the lowest temperature rise.


Assuntos
Guta-Percha/química , Materiais Restauradores do Canal Radicular/química , Preparo de Canal Radicular/métodos , Temperatura , Termometria/instrumentação , Dente Pré-Molar , Humanos , Técnicas In Vitro , Teste de Materiais , Propriedades de Superfície
10.
Acta ortop. bras ; 13(5): 221-224, 2005. ilus, tab
Artigo em Português | LILACS | ID: lil-420409

RESUMO

As fraturas da patela são prevalentes na faixa etária de 20 a 50 anos e representam 1 por cento das fraturas. São classificadas através de 2 aspectos principais: característica do traço de fratura e presença de exposição óssea, o que dirige a escolha do tratamento dentro das diversas técnicas propostas. Este trabalho objetivou estudar a incidência dos padrões de fraturas patelares e analisar os resultados funcionais encontrados com as diferentes modalidades de tratamento no IOT-HC-FMUSP. Levantou-se 103 prontuários de pacientes com fratura de patela tratados no IOT no período de 1988 - 1999 com seguimento mínimo de 5 anos. A média etária foi de 39,4 anos, 68 por cento do sexo masculino, 51,5 por cento de acometimento do lado direito e 2,9 por cento de bilateralidade. Prevaleceram fraturas transversas (36 por cento); 30 por cento de exposição óssea; técnicas mais utilizadas patelectomia parcial (46,6 por cento), banda de tensão (20,4 por cento), imobilização gessada (17,5 por cento), cerclagem (4,8 por cento) e patelectomia total (2,9 por cento); notou-se 57,1 por cento de excelentes e bons resultados com banda de tensão AO e 44,4 por cento nas patelectomias parciais. Concluiu-se que o resultado funcional final do tratamento da fratura de patela é multifatorial; o tipo de fratura, o modo de tratamento - conservador ou cirúrgico, a idade e o mecanismo de trauma não influenciam, isoladamente, o sucesso da terapêutica.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Avaliação de Resultado de Intervenções Terapêuticas , Patela/fisiopatologia , Patela/lesões , Patela , Terapêutica/métodos , Brasil , Patela/cirurgia , Estudos Retrospectivos , Prontuários Médicos/estatística & dados numéricos
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