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Autor: Starý, Vladimír

11 záznamů v Medvik Filtry

Kniha

Biomateriály a biotolerance

Starý, Vladimír, 1942-
Autor Autorita
Denk, František
Autor Autorita
České vysoké učení technické v Praze. Strojní fakulta
Autor Autorita

Praha : České vysoké učení technické v Praze, 2020

1. vydání 166 stran : ilustrace ; 30 cm

Vysokoškolská učebnice, která se zaměřuje na vývoj a aplikaci biomateriálů ve zdravotnictví.

MeSH
biokompatibilní materiály MeSH

Konspekt
Obecná biologie
Učební osnovy. Vyučovací předměty. Učebnice
NLK Obory
biologie
biomedicínské inženýrství
NLK Publikační typ
učebnice vysokých škol

Článek

Growth of a TiNb adhesion interlayer for bioactive coatings

Materials science & engineering. C, Materials for biological applications. 2017 ; 80 (-) : 652-658. [pub] 20170712

Mater Sci Eng C Mater Biol Appl
ISSN 1873-0191
Medvik
Zdroj

Surface bioactivity has been under intensive study with reference to its use in medical implants. Our study is focused on coatings prepared from an electroactive material which can support bone cell adhesion. Until now, hydroxyapatite films have usually been utilized as a chemically-active surface agent. However, electrically-active films could set a new direction in hard tissue replacement. As a base for these films, it is necessary to prepare an intermediate film, which can serve as a suitable barrier against the possible diffusion of some allergens and toxic elements from the substrate. The intermediate film also improves the adaptation of the mechanical properties of the basic material to an electroactive film. The aim of our work was to select an implantable and biocompatible material for this intermediate film that is suitable for coating several widely-used materials, to check the possibility of preparing an electroactive film for use on a material of this type, and to characterize the structure and several mechanical properties of this intermediate film. TiNb was selected as the material for the intermediate film, because of its excellent chemical and mechanical properties. TiNb coatings were deposited by magnetron sputtering on various substrates, namely Ti, Ti6Al4V, stainless steel, and bulk TiNb (as standard), and important properties of the layers, e.g. surface morphology and surface roughness, crystalline structure, etc., were characterized by several methods (SEM, EBSD, X-ray diffraction, nanoindentation and roughness measurement). It was found that the structure and the mechanical properties of the TiNb layer depended significantly on the type of substrate. TiNb was then used as a substrate for depositing a ferroelectrically active material, e.g., BaTiO3, and the adhesion, viability and proliferation of human osteoblast-like Saos-2 cells on this system were studied. We found that the electroactive BaTiO3 film was not only non-cytotoxic (i.e. it did not affect the cell viability). It also enhanced the growth of Saos-2 cells in comparison with pure TiNb and with standard tissue culture polystyrene wells, and also in comparison with BaTiO3 films deposited on Ti, i.e. a material clinically used for implantation into the bone.

Článek

Interaction of human osteoblast-like Saos-2 and MG-63 cells with thermally oxidized surfaces of a titanium-niobium alloy

PLoS One. 2014 ; 9 (6) : e100475.

ISSN 1932-6203
Medvik
Zdroj

An investigation was made of the adhesion, growth and differentiation of osteoblast-like MG-63 and Saos-2 cells on titanium (Ti) and niobium (Nb) supports and on TiNb alloy with surfaces oxidized at 165°C under hydrothermal conditions and at 600°C in a stream of air. The oxidation mode and the chemical composition of the samples tuned the morphology, topography and distribution of the charge on their surfaces, which enabled us to evaluate the importance of these material characteristics in the interaction of the cells with the sample surface. Numbers of adhered MG-63 and Saos-2 cells correlated with the number of positively-charged (related with the Nb2O5 phase) and negatively-charged sites (related with the TiO2 phase) on the alloy surface. Proliferation of these cells is correlated with the presence of positively-charged (i.e. basic) sites of the Nb2O5 alloy phase, while cell differentiation is correlated with negatively-charged (acidic) sites of the TiO2 alloy phase. The number of charged sites and adhered cells was substantially higher on the alloy sample oxidized at 600°C than on the hydrothermally treated sample at 165°C. The expression values of osteoblast differentiation markers (collagen type I and osteocalcin) were higher for cells grown on the Ti samples than for those grown on the TiNb samples. This was more particularly apparent in the samples treated at 165°C. No considerable immune activation of murine macrophage-like RAW 264.7 cells on the tested samples was found. The secretion of TNF-α by these cells into the cell culture media was much lower than for either cells grown in the presence of bacterial lipopolysaccharide, or untreated control samples. Thus, oxidized Ti and TiNb are both promising materials for bone implantation; TiNb for applications where bone cell proliferation is desirable, and Ti for induction of osteogenic cell differentiation.

MeSH
biologické markery metabolismus MeSH
buněčná adheze účinky léků MeSH
buněčná diferenciace účinky léků MeSH
buněčné linie MeSH
kolagen typu I metabolismus MeSH
lidé MeSH
lipopolysacharidy farmakologie MeSH
makrofágy cytologie účinky léků metabolismus MeSH
myši MeSH
osteoblasty cytologie účinky léků metabolismus MeSH
osteokalcin metabolismus MeSH
oxidace-redukce MeSH
povrchové vlastnosti MeSH
proliferace buněk účinky léků MeSH
slitiny chemie farmakologie MeSH
statická elektřina MeSH
tkáňové podpůrné struktury * MeSH
TNF-alfa farmakologie MeSH
vysoká teplota MeSH
zvířata MeSH
Check Tag
lidé MeSH
myši MeSH
zvířata MeSH
Publikační typ
časopisecké články MeSH
práce podpořená grantem MeSH

Článek

Influence of surface roughness of carbon materials on human osteoblast-like cell growth

Journal of biomedical materials research. Part A. 2014 ; 102 (6) : 1868-79.

J Biomed Mater Res
ISSN 1552-4965
Medvik
Zdroj

This article presents a study of the dependence of the biocompatibility of a carbon-based material, namely a 2D C/C composite, on mechanical and chemical surface modifications. The mechanical modifications were surface grinding and polishing, and chemical modifications were made by depositing thin layers of pyrolytic carbon, titanium-carbon and DLC layers. Human osteoblast-like MG 63 cells were cultivated on these materials. The densities of the cells after one-day cultivation and after four-day cultivation, and the average cell spreading area after one-day cultivation, were evaluated in dependence on particular surface roughness parameters. The minima of the cell density on pyrolytic carbon and titanium-carbon layers were found; they were connected with the maxima of the average cell area. For DLC, the cell area decreased as the roughness parameter Ra increased in the range 0.1-10 µm, although the minimum appeared for the density of the cells. Using a multivariate test, the dependences of the biocompatibility parameters on the layer material and on surface grinding were statistically significant. The results suggest that the optimal roughness parameters for MG 63 cell on carbon based surface were Ra ∼ 3.5 µm, RSm ∼0.03-0.08 mm, Rsk ∼0 or negative and Rku ∼ 20, DLC being the best material choice. These values of roughness were obtained by simple mechanical grinding of substrate and coating by DLC layer.

Článek

On the role of Nb-related sites of an oxidized β-TiNb alloy surface in its interaction with osteoblast-like MG-63 cells

Materials science & engineering. C, Materials for biological applications. 2013 ; 33 (3) : 1636-45.

Mater Sci Eng C Mater Biol Appl
ISSN 0928-4931
Medvik
Zdroj

β-Stabilized titanium (Ti) alloys containing non-toxic elements, particularly niobium (Nb), are promising materials for the construction of bone implants. Their biocompatibility can be further increased by oxidation of their surface. Therefore, in this study, the adhesion, growth and viability of human osteoblast-like MG 63 cells in cultures on oxidized surfaces of a β-TiNb alloy were investigated and compared with the cell behavior on thermally oxidized Ti, i.e. a metal commonly used for constructing bone implants. Four experimental groups of samples were prepared: Ti or TiNb samples annealed to 600 °C for 60 min in a stream of dry air, and Ti and TiNb samples treated in Piranha solution prior to annealing. We found that on all TiNb-based samples, the cell population densities on days 1, 3 and 7 after seeding were higher than on the corresponding Ti-based samples. As revealed by XPS and Raman spectroscopy, and also by isoelectric point measurements, these results can be attributed to the presence of T-Nb2O5 oxide phase in the surface of the alloy sample, which decreased its negative zeta (ζ)-potential in comparison with zeta (ζ)-potential of the Ti sample at physiological pH. This effect was tentatively explained by the presence of positively charged defects acting as Lewis sites of the surface Nb2O5 phase. Piranha treatment slightly decreases the biocompatibility of the samples, which for the alloy samples may be explained by a decrease in the number of defective sites with this treatment. Thus, the presence of Nb and thermal oxidation of β-stabilized Ti alloys play a significant role in the increased biocompatibility of TiNb alloys.