- Klíčová slova
- vizualizace výdechových kapének,
- MeSH
- diagnostické techniky dýchacího ústrojí MeSH
- dýchání ústy MeSH
- lidé MeSH
- pilotní projekty MeSH
- pozorovací studie jako téma MeSH
- vydechnutí * MeSH
- zátěžový test * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- abstrakt z konference MeSH
- práce podpořená grantem MeSH
The goal of our study is to design BaTiO3 ferroelectric layers that will cover metal implants and provide improved osseointegration. We synthesized ferroelectric BaTiO3 layers on Pt/fused silica substrates, and we studied their physical and bio-properties. BaTiO3 and Pt layers were prepared using KrF excimer laser ablation at substrate temperature Ts in the range from 200°C to 750°C in vacuum or under oxygen pressure of 10 Pa, 15 Pa, and 20 Pa. The BaTiO3/Pt and Pt layers adhered well to the substrates. BaTiO3 films of crystallite size 60-140 nm were fabricated. Ferroelectric loops were measured and ferroelectricity was also confirmed using Raman scattering measurements. Results of atomic force microscopy topology and the X-ray diffraction structure of the BaTiO3/Pt/fused silica multilayers are presented. The adhesion, viability, growth, and osteogenic differentiation of human osteoblast-like Saos-2 cells were also studied. On days 1, 3, and 7 after seeding, the lowest cell numbers were found on non-ferroelectric BaTiO3, while the values on ferroelectric BaTiO3, on non-annealed and annealed Pt interlayers, and on the control tissue culture polystyrene dishes and microscopic glass slides were similar, and were usually significantly higher than on non-ferroelectric BaTiO3. A similar trend was observed for the intensity of the fluorescence of alkaline phosphatase, a medium-term marker of osteogenic differentiation, and of osteocalcin, a late marker of osteogenic differentiation. At the same time, the cell viability, tested on day 1 after seeding, was very high on all tested samples, reaching 93-99%. Ferroelectric BaTiO3 films deposited on metallic bone implants through a Pt interlayer can therefore markedly improve the osseointegration of these implants in comparison with non-ferroelectric BaTiO3 films.
- MeSH
- buněčné linie MeSH
- elektřina MeSH
- kostní náhrady chemie MeSH
- lasery MeSH
- lidé MeSH
- nanočástice chemie ultrastruktura MeSH
- osteoblasty cytologie MeSH
- osteogeneze MeSH
- oxid křemičitý chemie MeSH
- platina chemie MeSH
- protézy a implantáty MeSH
- sloučeniny barya chemie MeSH
- titan chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Diamond-like carbon (DLC) thin films are promising for use in coating orthopaedic, dental and cardiovascular implants. The problem of DLC layers lies in their weak layer adhesion to metal implants. Chromium is used as a dopant for improving the adhesion of DLC films. Cr-DLC layers were prepared by a hybrid technology, using a combination of pulsed laser deposition (PLD) from a graphite target and magnetron sputtering. Depending on the deposition conditions, the concentration of Cr in the DLC layers moved from zero to 10.0 at.%. The effect of DLC layers with 0.0, 0.9, 1.8, 7.3, 7.7 and 10.0 at.% Cr content on the adhesion and osteogenic differentiation of human osteoblast-like Saos-2 cells was assessed in vitro. The DLC samples that contained 7.7 and 10.0 at.% of Cr supported cell spreading on day 1 after seeding. On day three after seeding, the most apparent vinculin-containing focal adhesion plaques were also found on samples with higher concentrations of chromium. On the other hand, the expression of type I collagen and alkaline phosphatase at the mRNA and protein level was the highest on Cr-DLC samples with a lower concentration of Cr (0-1.8 at.%). We can conclude that higher concentrations of chromium supported cell adhesion; however DLC and DLC doped with a lower concentration of chromium supported osteogenic cell differentiation.
- MeSH
- alkalická fosfatasa metabolismus MeSH
- biokompatibilní potahované materiály MeSH
- buněčná adheze * MeSH
- buněčná diferenciace * MeSH
- buněčné linie MeSH
- chrom chemie MeSH
- diamant chemie MeSH
- fokální adheze MeSH
- kolagen typu I metabolismus MeSH
- kovy chemie MeSH
- lasery MeSH
- lidé MeSH
- messenger RNA metabolismus MeSH
- osteoblasty cytologie MeSH
- osteogeneze MeSH
- povrchové vlastnosti MeSH
- stanovení celkové genové exprese MeSH
- talin chemie MeSH
- uhlík chemie MeSH
- vinkulin metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BaTiO3 (BTO) layers were deposited by pulsed laser deposition (PLD) on TiNb, Pt/TiNb, Si (100), and fused silica substrates using various deposition conditions. Polycrystalline BTO with sizes of crystallites in the range from 90nm to 160nm was obtained at elevated substrate temperatures of (600°C-700°C). With increasing deposition temperature above 700°C the formation of unwanted rutile phase prevented the growth of perovskite ferroelectric BTO. Concurrently, with decreasing substrate temperature below 500°C, amorphous films were formed. Post-deposition annealing of the amorphous deposits allowed obtaining perovskite BTO. Using a very thin Pt interlayer between the BTO films and TiNb substrate enabled high-temperature growth of preferentially oriented BTO. Raman spectroscopy and electrical characterization indicated polar ferroelectric behaviour of the BTO films.
- MeSH
- biokompatibilní materiály chemie MeSH
- difrakce rentgenového záření MeSH
- elektřina MeSH
- elektrody MeSH
- lasery * MeSH
- mikroskopie elektronová rastrovací MeSH
- niob chemie MeSH
- oxid křemičitý chemie MeSH
- protézy a implantáty * MeSH
- Ramanova spektroskopie MeSH
- slitiny chemie MeSH
- sloučeniny barya chemie MeSH
- titan chemie MeSH
- Publikační typ
- časopisecké články MeSH
Chromium-enriched diamond-like carbon (DLC) layers were prepared by a hybrid technology using a combination of pulsed laser deposition (PLD) and magnetron sputtering. XRD revealed no chromium peaks, indicating that the layers are mostly amorphous. Carbon (sp(2) and sp(3) bonds) and chromium bonds were determined by XPS from C 1s, O 1s, and Cr 2p photoelectron peaks. Depending on the deposition conditions, the concentration of Cr in DLC layers moved from zero to 10 at.% for as-received sample surfaces, and to about 31 at.% after mild sputter-cleaning by argon ion cluster beam. It should be noted that the most stable Cr(3+) bonding state is in Cr2O3 and Cr(OH)3, and that there is the toxic Cr(6+) state in CrO3. The surface content of hexavalent chromium in the Cr 2p3/2 spectra is rather low, but discernible. The population density of Saos-2 cells was the highest in samples containing higher concentrations of chromium 7.7 and 10 at.%. This means that higher concentrations of chromium supported the cell adhesion and proliferation. In addition, as revealed by a LIVE/DEAD viability/cytotoxicity kit, the cells on all Cr-containing samples maintained high viability (96 to 99%) on days 1 and 3 after seeding. However, this seemingly positive cell behavior could be associated with the risk of dedifferentiation and oncogenic transformation of cells.
- MeSH
- biokompatibilní materiály chemie toxicita MeSH
- chrom chemie MeSH
- diamant chemie MeSH
- lasery MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Titanium dioxide (TiO2) and Ag-incorporated diamond-like carbon (DLC) films were prepared on different substrates. The films were prepared by pulsed laser deposition (PLD). TiO2 and Ag were selected due to their potential values as biomaterials. Silver is effective against a wide range of spectrum including Gram-negative and Gram-positive bacteria and yeast. TiO2 and Ag-incorporated DLC thin films are suitable candidates for application on biomedical devices and implants due to their biocompatibility, chemical inertness, and mechanical properties. Thin films are widely used in coronary artery stents, dental implants, heart valves and other vascular devices. The microstructure and antibacterial properties of TiO2 and silver-doped diamond-like carbon (DLC) films have been investigated. The films structural quality was evaluated using SEM microscopy, AFM microscopy and Raman spectroscopy. The antibacterial activity was determined using Gram-negative bacteria Escherichia coli and Gram-positive bacteria Bacillus subtilis. Our results demonstrate that the TiO2, nitrogen doped titanium oxides TON and Ag-incorporated DLC films are potentially useful as biomedical materials having good antibacterial properties.
Diamond-like carbon (DLC) thin films are frequently used for coating of implants. The problem of DLC layers lies in bad layer adhesion to metal implants. Chromium is used as a dopant for improvement of adhesion of DLC films. DLC and Cr-DLC layers were deposited on silicon, Ti6Al4V and CoCrMo substrates by a hybrid technology using combination of pulsed laser deposition (PLD) and magnetron sputtering. The topology of layers was studied using SEM, AFM and mechanical profilometer. Carbon and chromium content and concentration of trivalent and toxic hexavalent chromium bonds were determined by XPS and WDS. It follows from the scratch tests that Cr doping improved adhesion of DLC layers. Ethylene glycol, diiodomethane and deionized water were used to measure the contact angles. The surface free energy (SFE) was calculated. The antibacterial properties were studied using Pseudomonas aeruginosa and Staphylococcus aureus bacteria. The influence of SFE, hydrophobicity and surface roughness on antibacterial ability of doped layers is discussed.
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- MeSH
- biofyzika záření MeSH
- fotometrie MeSH
- lasery MeSH
- luminiscenční měření MeSH
- optika a fotonika MeSH
- spektrofotometrie MeSH
- Konspekt
- Biochemie. Molekulární biologie. Biofyzika
- NLK Obory
- fyzika, biofyzika
- NLK Publikační typ
- učebnice vysokých škol
Pulsed laser deposition was proved as a suitable method for hydroxyapatite (HA) coating of coaxial poly-ɛ-caprolactone/polyvinylalcohol (PCL/PVA) nanofibers. The fibrous morphology of PCL/PVA nanofibers was preserved, if the nanofiber scaffold was coated with thin layers of HA (200 nm and 400 nm). Increasing thickness of HA, however, resulted in a gradual loss of fibrous character. In addition, biomechanical properties were improved after HA deposition on PCL/PVA nanofibers as the value of Young's moduli of elasticity significantly increased. Clearly, thin-layer hydroxyapatite deposition on a nanofiber surface stimulated mesenchymal stem cell viability and their differentiation into osteoblasts. The optimal depth of HA was 800 nm.
- MeSH
- buněčná diferenciace účinky léků MeSH
- hydroxyapatit chemie farmakologie MeSH
- mezenchymální kmenové buňky cytologie MeSH
- nanovlákna chemie MeSH
- osteoblasty cytologie MeSH
- polyestery chemie MeSH
- polyvinylalkohol chemie MeSH
- prasata MeSH
- proliferace buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- biokompatibilní potahované materiály terapeutické užití MeSH
- fibroblasty fyziologie MeSH
- financování organizované MeSH
- hydroxyapatit terapeutické užití MeSH
- imunohistochemie využití MeSH
- keratinocyty fyziologie chemie MeSH
- krystalizace metody využití MeSH
- lidé MeSH
- zubní implantáty trendy využití MeSH
- zubní materiály terapeutické užití MeSH
- Check Tag
- lidé MeSH
