Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
J Biomed Mater Res A ; 105(2): 424-432, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27684050

RESUMEN

The aim of the study has been to evaluate the morphology, proliferation, and pluripotency maintenance of mouse embryonic stem cells (mESCs) cultivated on poly(lactic-co-glycolic acid) scaffolds. The scaffolds were hydrolyzed with NaOH (treated) and nonhydrolyzed (untreated). Morphological and mechanical characterization of the scaffolds was performed. mESC were evaluated for cell viability, cytotoxicity, expression of pluripotency markers, colony morphology, and overall distribution. The treatment generated a reduction in the hydrophobic characteristics of the scaffolds, leading to a higher wettability compared to the untreated group. The viability, cytotoxicity, number of colonies, and the thickness of the cell layer presented similar results between the scaffold groups. The viability test showed that it was possible to cultivate the mESCs on the scaffolds. The cytotoxicity analysis showed that the PLGA scaffolds were not harmful for the cells. The cells maintained the expression of the pluripotency markers Oct4 and Sox2. The number of colonies and the thickness of the cell layer on the scaffold showed that they were not able to colonize the entire volume of the scaffolds. The area occupied by the mESCs was the same between the treated and untreated groups after 14 days in culture. It is possible to conclude that both conditions are equally suitable for maintaining mESC culture. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 424-432, 2017.


Asunto(s)
Proliferación Celular , Ensayo de Materiales , Células Madre Embrionarias de Ratones/metabolismo , Poliglactina 910/química , Andamios del Tejido/química , Animales , Femenino , Ratones , Células Madre Embrionarias de Ratones/citología
2.
Drug Discov Today ; 21(8): 1243-56, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27155458

RESUMEN

Whereas highly porous scaffolds composed of electrospun nanofibers can mimick major features of the extracellular matrix in tissue engineering, they lack the ability to incorporate and release biocompounds (drugs, growth factors) safely in a controlled way. Here, electrospun core-shell fibers (core made from water and aqueous solutions of hydrophilic polymers and the shell from materials with well-defined release mechanisms) offer unique advantages in comparison with those that have helped make porous nanofibrillar scaffolds highly successful in tissue engineering. This review considers the preparation and biofunctionalization of such core-shell fibers as well as applications in various areas, including neural, vascular, cardiac, cartilage and bone tissue engineering, and touches on the topic of clinical trials.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanofibras , Ingeniería de Tejidos , Animales , Humanos , Nanotecnología , Tecnología Farmacéutica
3.
Biomed Res Int ; 2015: 967814, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25667931

RESUMEN

Electrospun nanofibers composed of polymers have been extensively researched because of their scientific and technical applications. Commercially available polyhydroxybutyrate (PHB) and polyhydroxybutyrate-co-valerate (PHB-HV) copolymers are good choices for such nanofibers. We used a highly integrated method, by adjusting the properties of the spinning solutions, where the cyanophyte Arthrospira (formally Spirulina) was the single source for nanofiber biofunctionalization. We investigated nanofibers using PHB extracted from Spirulina and the bacteria Cupriavidus necator and compared the nanofibers to those made from commercially available PHB and PHB-HV. Our study assessed nanofiber formation and their selected thermal, mechanical, and optical properties. We found that nanofibers produced from Spirulina PHB and biofunctionalized with Spirulina biomass exhibited properties which were equal to or better than nanofibers made with commercially available PHB or PHB-HV. Our methodology is highly promising for nanofiber production and biofunctionalization and can be used in many industrial and life science applications.


Asunto(s)
Materiales Biocompatibles/química , Biopolímeros/química , Nanofibras/química , Spirulina/química , Biomasa , Hidroxibutiratos/química , Valeratos/química
4.
J Biomed Nanotechnol ; 8(2): 211-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22515072

RESUMEN

Tissue engineering is a potential approach to regenerate damaged tissue by the combination and synergism among the scaffolding material, cell source and signaling factors. In the present study, mesenchymal stem cells (MSCs) were isolated from C57BL/6 mice, cultured on poly(D, L-lactide-co-glycolide) (PLGA) scaffold produced by electrospinning technique and differentiated into chondrogenic lineage. After seeding, MSCs were responsive and became flattened with fibroblast-like morphology demonstrated by the presence of actin stress fibers. Integrin-beta1 receptor blockage reduced significantly cell adhesion with loss of actin stress fibers, demonstrating the ability of PLGA nanofiber to trigger integrin receptor-mediated cell adhesion. Present data contribute to the understanding of MSCs' behavior on these biodegradable and biocompatible scaffolds that can be used as carriers in treatments involving cell transplantation.


Asunto(s)
Adhesión Celular/fisiología , Integrina beta1/metabolismo , Ácido Láctico/química , Células Madre Mesenquimatosas/citología , Nanofibras/química , Ácido Poliglicólico/química , Animales , Antígenos CD/metabolismo , Materiales Biocompatibles/química , Diferenciación Celular , Células Cultivadas , Citometría de Flujo , Ensayo de Materiales , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , Microscopía Confocal , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Andamios del Tejido/química
5.
Int J Biol Macromol ; 49(4): 480-6, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21664927

RESUMEN

The aim of this work has been to elaborate well defined gliadin nanofibers with incorporation of inorganic molecules, such as polyhedral oligomeric silsesquioxane (POSS). Nanofibers were obtained by electrospinning processing, controlling the relevant parameters such as tip-to-collector distance, voltage and feed rate. The fiber mats were characterized by SEM, confocal images, DSC, viscosity, FTIR and conductivimetry analysis. FTIR spectra showed characteristic absorption bands related to the presence of POSS-NH(2) within the matrices. SEM micrographs showed that gliadin fibers decreased their dimensions as the amount of POSS-NH(2) increased in the spinning solution. The electrical conductivity of gliadin solutions diminished as the concentration of POSS-NH(2) was increased. Besides, confocal micrographs revealed that POSS-NH(2) might be dispersed as nanocrystals into gliadin and gluten fibers. The dimension of gluten nanofibers was also affected by the POSS-NH(2) concentration, but conversely, this dependence was not proportional to the POSS-NH(2) amount. Somehow, the interaction between gliadin and POSS-NH(2) in aqueous TFE affected the solution viscosity and, as a consequence, higher jet instabilities and thinner fiber dimensions were obtained.


Asunto(s)
Gliadina/química , Glútenes/química , Nanofibras/química , Nanotecnología/métodos , Compuestos de Organosilicio/química , Conductividad Eléctrica , Gliadina/ultraestructura , Glútenes/ultraestructura , Microscopía Fluorescente , Modelos Moleculares , Nanofibras/ultraestructura , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura de Transición , Viscosidad
6.
Bioresour Technol ; 101(8): 2872-6, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20056537

RESUMEN

Spirulina is a microalga which offers biological functions highly favorable for tissue engineering. Highly porous scaffolds can be produced by electrospinning containing biomass of Spirulina. The goal of this contribution was therefore to establish spinning conditions allowing to produce well defined nanofibers with diameters down to about 100 nm and to produce nanofibers with various concentration of the biomass for subsequent studies in tissue engineering applications. The experimental results reveal that the blend system PEO/biomass is behaved surprisingly well in electrospinning. Very thin bead-free nanofibers with diameters of about 110 nm can be produced for different biomass contents of up to 67 wt.% of the nanofibers and for PEO concentrations in the spinning solution well below 4 wt.%. These results suggest to us the use of the biomass containing nanofibers as extracellular matrices for stem cell culture and future treatment of spinal chord injury.


Asunto(s)
Biotecnología/métodos , Nanofibras/microbiología , Spirulina , Ingeniería de Tejidos/métodos , Reactores Biológicos , Brasil
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA