Liberec, Czech Republic
Liberec, Czech Republic
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Holan V.,Academy of Sciences of the Czech Republic | Holan V.,Charles University | Chudickova M.,Academy of Sciences of the Czech Republic | Chudickova M.,Charles University | And 13 more authors.
Journal of Controlled Release | Year: 2011

Cyclosporine A (CsA), a potent immunosuppressive drug with low water solubility, was dissolved in poly(L-lactic acid) (PLA) solution, and nanofibers were fabricated from this mixture by electrospinning technology. The addition of CsA into the PLA solution and the conditions of the electrospinning process did not influence the structure of the nanofibers nor affect the pharmacological activity of CsA. Study of the CsA release behavior in culture medium showed a release for at least 96 h. After the topical application of CsA-loaded nanofibers on skin allografts in vivo, the release was significantly slower and about 35% of the drug was still retained in the nanofibers on day 8. The addition of CsA-loaded nanofibers into cultures of mouse spleen cells stimulated with Concanavalin A selectively inhibited T cell functions; the activity of stimulated macrophages or the growth of non-T-cell populations was not suppressed in the presence of CsA-loaded nanofibers. The covering of skin allografts with CsA-loaded nanofibers significantly attenuated the local production of the proinflammatory cytokines IL-2, IFN-γ and IL-17. These results suggest that CsA-loaded electrospun nanofibers can serve as effective drug carriers for the local/topical suppression of an inflammatory reaction and simultaneously could be used as scaffolds for cell-based therapy. © 2011 Elsevier B.V. All rights reserved.

Novotna K.,Academy of Sciences of the Czech Republic | Zajdlova M.,Academy of Sciences of the Czech Republic | Suchy T.,Czech Institute of Rock Structure And Mechanics | Hadraba D.,Academy of Sciences of the Czech Republic | And 18 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2014

Various types of nanofibers are increasingly used in tissue engineering, mainly for their ability to mimic the architecture of tissue at the nanoscale. We evaluated the adhesion, growth, viability, and differentiation of human osteoblast-like MG 63 cells on polylactide (PLA) nanofibers prepared by needle-less electrospinning and loaded with 5 or 15 wt % of hydroxyapatite (HA) nanoparticles. On day 7 after seeding, the cell number was the highest on samples with 15 wt % of HA. This result was confirmed by the XTT test, especially after dynamic cultivation, when the number of metabolically active cells on these samples was even higher than on control polystyrene. Staining with a live/dead kit showed that the viability of cells on all nanofibrous scaffolds was very high and comparable to that on control polystyrene dishes. An enzyme-linked immunosorbent assay revealed that the concentration of osteocalcin was also higher in cells on samples with 15 wt % of HA. There was no immune activation of cells (measured by production of TNF-alpha), associated with the incorporation of HA. Moreover, the addition of HA suppressed the creep behavior of the scaffolds in their dry state. Thus, nanofibrous PLA scaffolds have potential for bone tissue engineering, particularly those with 15 wt % of HA. © 2013 Wiley Periodicals, Inc.

Viter R.,Odessa I I Mechnikov National University | Starodub N.,National University of Life and Environmental Sciences of Ukraine | Smyntyna V.,Odessa I I Mechnikov National University | Tereschenko A.,Odessa I I Mechnikov National University | And 4 more authors.
Procedia Engineering | Year: 2011

The presented paper is devoted to investigation of properties of silica nanofibers hydrogels for biosensors applications. SiO 2 nanofibers were prepared by the electrospinning method from polymeric solutions, containing SiO 2 precursor, followed by a calcination procedure to obtain highly crystalline, pure inorganic nanofiber materials. The structural properties have been investigated by Scanning electron microscopy (SEM). Hydrogels were prepared by mixing of SiO 2 nanofibers in distilled water. Photoluminescence (PL) spectra (excitation with λ=266 nm) of SiO 2 hydrogels with immobilized antigens (Ag) and antibodies (Ab) in the range were studied in the region 370-620 nm. Experimental dependence of PL properties of SiO 2 hydrogels with immobilized Ag on Ab concentration was studied. © 2011 Published by Elsevier Ltd.

Zukalova M.,J. Heyrovsky Institute of Physical Chemistry | Prochazka J.,J. Heyrovsky Institute of Physical Chemistry | Bastl Z.,J. Heyrovsky Institute of Physical Chemistry | Duchoslav J.,Elmarco | And 3 more authors.
Chemistry of Materials | Year: 2010

Nanocrystalline fibrous TiO2 (anatase) was prepared by electrostatic spinning from ethanolic solution of Ti(IV) butoxide, acetylacetone, and poly(vinylpyrrolidone) employing the Nanospider industrial process. These titania fibers were smoothly converted into cubic titanium oxynitride, TiOxNy fibers (a=4.1930Å ) during 4 h at 600 °Cin ammonia atmosphere. The obtainedmaterial is convertible back into TiO2 fibers by heat treatment in air at 500 °C. The TiO 2 fibers, which were reformed in this way, contain anatase as the main phase. Their follow-up reaction with NH3 at 600 °C/2 h leads to a less crystalline oxynitride material with a ≈ 4.173Å , which is close to that of cubic TiO. Three subsequent cycles of this transformation were demonstrated. The described conversions are specific for electrospun anatase fibers only. At the same experimental conditions, other forms of nanocrystalline anatase do not react with ammonia yielding cubic phases. An almost perfectly stoichiometric titanium nitride, TiN(a=4.2290Å ) containing only 0.2 wt% O, was prepared from TiOxNy fibers in NH3 at temperatures up to 1000 °C. This TiN material maintains the morphology of fibers and is composed of nanocrystals of a similar size as those of the precursor. © 2010 American Chemical Society.

Zajicova A.,Academy of Sciences of the Czech Republic | Pokorna K.,Academy of Sciences of the Czech Republic | Pokorna K.,Charles University | Lencova A.,Academy of Sciences of the Czech Republic | And 12 more authors.
Cell Transplantation | Year: 2010

Stem cell (SC) therapy represents a promising approach to treat a wide variety of injuries, inherited diseases, or acquired SC deficiencies. One of the major problems associated with SC therapy remains the absence of a suitable matrix for SC growth and transfer. We describe here the growth and metabolic characteristics of mouse limbal stem cells (LSCs) and mesenchymal stem cells (MSCs) growing on 3D nanofiber scaffolds fabricated from polyamide 6/12 (PA6/12). The nanofibers were prepared by the original needleless electrospun Nanospider technology, which enables to create nanofibers of defined diameter, porosity, and a basis weight. Copolymer PA6/12 was selected on the basis of the stability of its nanofibers in aqueous solutions, its biocompatibility, and its superior properties as a matrix for the growth of LSCs, MSCs, and corneal epithelial and endothelial cell lines. The morphology, growth properties, and viability of cells grown on PA6/12 nanofibers were comparable with those grown on plastic. LSCs labeled with the fluorescent dye PKH26 and grown on PA6/12 nanofibers were transferred onto the damaged ocular surface, where their seeding and survival were monitored. Cotransfer of LSCs with MSCs, which have immunosuppressive properties, significantly inhibited local inflammatory reactions and supported the healing process. The results thus show that nanofibers prepared from copolymer PA6/12 represent a convenient scaffold for growth of LSCs and MSCs and transfer to treat SC deficiencies and various ocular surface injuries. Copyright © 2010 Cognizant Comm. Corp.

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