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1.
Neurorehabil Neural Repair ; 35(8): 729-737, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34047233

RESUMO

BACKGROUND: Functional imaging studies have associated dystonia with abnormal activation in motor and sensory brain regions. Commonly used techniques such as functional magnetic resonance imaging impose physical constraints, limiting the experimental paradigms. Functional near-infrared spectroscopy (fNIRS) offers a new noninvasive possibility for investigating cortical areas and the neural correlates of complex motor behaviors in unconstrained settings. METHODS: We compared the cortical brain activation of patients with focal upper-limb dystonia and controls during the writing task under naturalistic conditions using fNIRS. The primary motor cortex (M1), the primary somatosensory cortex (S1), and the supplementary motor area were chosen as regions of interest (ROIs) to assess differences in changes in both oxyhemoglobin (oxy-Hb) and deoxyhemoglobin (deoxy-Hb) between groups. RESULTS: Group average activation maps revealed an expected pattern of contralateral recruitment of motor and somatosensory cortices in the control group and a more bilateral pattern of activation in the dystonia group. Between-group comparisons focused on specific ROIs revealed an increased activation of the contralateral M1 and S1 cortices and also of the ipsilateral M1 cortex in patients. CONCLUSIONS: Overactivity of contralateral M1 and S1 in dystonia suggest a reduced specificity of the task-related cortical areas, whereas ipsilateral activation possibly indicates a primary disorder of the motor cortex or an endophenotypic pattern. To our knowledge, this is the first study using fNIRS to assess cortical activity in dystonia during the writing task under natural settings, outlining the potential of this technique for monitoring sensory and motor retraining in dystonia rehabilitation.


Assuntos
Distonia/diagnóstico por imagem , Escrita Manual , Córtex Motor/diagnóstico por imagem , Adulto , Mapeamento Encefálico , Distonia/fisiopatologia , Feminino , Neuroimagem Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho
2.
Artigo em Inglês | MEDLINE | ID: mdl-31803730

RESUMO

The present study aims to improve the hydrophobicity and durability of bacterial cellulose (BC) nonwoven by functionalization with poly(fluorophenol). To this end, laccase was first entrapped onto BC and then used to polymerize the fluorophenol {4-[4-(trifluoromethyl) phenoxy] phenol} in-situ. The polymerization of fluorophenol by laccase was confirmed through 1H NMR and MALDI-TOF analyses. The effect of poly(fluorophenol) on BC nonwoven was determined by evaluation of the surface hydrophobicity and olephobicity properties such as water contact angle (WCA), oil contact angle (OCA), surface energy and water/oil absorption time. After BC functionalization with poly(fluorophenol) (20 mM), the WCA increased from 54.5 ± 1.2° to 120 ± 1.5° while the surface energy decreased (11.58 ± 1.4 mN/m). The OCA was also increased from 46.5 ± 2.5° to 87 ± 2° along to the decrease of surface energy (8.7 ± 1.5°). X-ray photoelectron spectroscopy (XPS) analysis confirmed an increase in the fluorine content in BC from 5.27 to 17.57%. The findings confirmed the polymerization of fluorophenol by laccase and its entrapment onto a BC nanofiber structure. The durability of the functionalization with poly(fluorophenol) was confirmed by evaluating the washing fastness, tensile strength after washing and dimensional stability. The results indicate that the functionalized BC nonwoven had higher tensile strength (×10 times) and better dimensional stability (30%) than the non-functionalized BC nonwoven material.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 174: 279-285, 2017 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-27960141

RESUMO

OBJECTIVE: The purpose of this study is to elucidate the behavior of retinyl acetate in penetrating human skin without the presence of enhancers by using confocal Raman spectroscopy and molecular dynamics simulation. METHODS: In this study, in vivo confocal Raman spectroscopy was combined with molecular dynamics simulation to investigate the transdermal permeation of the aqueous suspension of retinyl acetate. RESULTS: Permeation was measured after 30min, and retinyl acetate was found up to 20µm deep inside the stratum corneum. The delivery of retinyl acetate inside a skin membrane model was studied by molecular dynamics. The membrane model that was used represented normal young skin containing a lipid bilayer with 25% ceramide, 36% fatty acid, 30% cholesterol, and 6% cholesterol sulfate. CONCLUSION: Spectroscopy data indicate that retinyl acetate permeates into the stratum corneum. Molecular dynamics data showed that retinyl acetate permeates in the membrane model and that their final location is deep inside the lipid bilayer. We showed, for the first time, a correlation between Raman permeation data and computational data.


Assuntos
Simulação de Dinâmica Molecular , Pele/efeitos dos fármacos , Análise Espectral Raman , Vitamina A/análogos & derivados , Adulto , Diterpenos , Feminino , Humanos , Bicamadas Lipídicas/química , Tamanho da Partícula , Ésteres de Retinil , Vitamina A/farmacologia
4.
J Biomed Mater Res B Appl Biomater ; 100(8): 2269-78, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22987762

RESUMO

The Ca(2+)-induced cold gelation technique was found suitable to prepare highly porous biodegradable scaffolds based on bovine serum albumin (BSA) and alpha-casein from bovine milk for tissue engineering. A 2(3) full factorial design was used to study the influence and impact of each factor on the several responses of the scaffolds. In vitro degradation (ID), swelling ratio (SR), porosity (PO), and pore size (PS) as well cytotoxicity (CT) were evaluated and shown to be dependent on the pH of sample preparation and on the amount of BSA and casein present, making these scaffolds tunable structures. Under optimized working conditions (4.19% of BSA, 0.69% of Casein, pH 7.07), the ID attained was 37.97%, the SR observed was 11.87, the PO was 82.11%, the PS measured was 180.63 µm at surface, and 175.91 µm at fracture, whereas maximum cell viability was 84% in comparison to controls. Moreover, the scaffold supported cell adhesion and proliferation. These results, consistent with the prediction by the experimental design approach, support the use of this methodology to develop tunable scaffolds for tissue engineering using the Ca(2+)-induced cold gelation.


Assuntos
Cálcio/química , Caseínas/química , Proliferação de Células , Embrião de Mamíferos/metabolismo , Fibroblastos/metabolismo , Teste de Materiais , Soroalbumina Bovina/química , Alicerces Teciduais/química , Animais , Bovinos , Adesão Celular , Células Cultivadas , Embrião de Mamíferos/citologia , Fibroblastos/citologia , Concentração de Íons de Hidrogênio , Camundongos , Porosidade , Engenharia Tecidual/métodos
5.
Biotechnol J ; 2(3): 370-3, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17183503

RESUMO

In the present study we examined the performance of a thermoalkalophilic bacterial consortium, where the predominant strain was Bacillus sp. SF, in the degradation of Reactive Black 5 (RB5). We used a reactor working in continuous mode and investigated the effects of pH, hydraulic retention time (HRT) and several added salts on colour and chemical oxygen demand (COD) reductions. For the chosen operational conditions (pH 9, 55 degrees C and HRT of 12 h) the efficiencies achieved were 91.2 +/- 0.8 % for colour removal and 81.2% for COD removal. The system tolerated, with no significant decrease in colour removal efficiency, 30 g/L Na(2)SO(4), Na(2)CO(3) or NaCl. The latter two salts, however, led to a reduction in COD removal of 30% and 50%, respectively. The system proved to be very effective in the decolourisation of C.I. RB5 under alkaline conditions and at a comparatively high temperature.


Assuntos
Bactérias/metabolismo , Cor , Têxteis/microbiologia , Bacillus/efeitos dos fármacos , Bacillus/metabolismo , Bactérias/efeitos dos fármacos , Reatores Biológicos/microbiologia , Carbonatos/farmacologia , Concentração de Íons de Hidrogênio , Naftalenossulfonatos/química , Naftalenossulfonatos/metabolismo , Cloreto de Sódio/farmacologia , Sulfatos/farmacologia , Temperatura , Indústria Têxtil/métodos
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