Cílem tohoto projektu jsou in vitro a in vivo hodnocení nově připravených a charakterizovaných nanokompozitních nosičů se strukturními a mechanickými vlastnostmi optimálními pro osazování mesenchymálními kmenovými buňkami (MSC). Jejich navrhované složení bude kombinovat výhody biodegradabilních alifatických polyesterů ve formě nanovláken, přírodního kolagenu jako matrice, a přírodního kalcium fosfátu ve formě nanočástic, to vše doplněno hyaluronanem sodným. Proces přípravy bude optimalizován s cílem dosažení homogenně porézní mikrostruktury se vzájemně propojenými póry s nano/mikro strukturovaným povrchem, s vhodnými mechanickými vlastnostmi a řízenou dobou biodegradace a to vše s ohledem na získání optimálního systému pro osazování MSC. Výsledky získané pomocí testů in vitro budou využity v testech in vivo na modelu miniaturních prasat.; Newly prepared and characterized nanocomposite scaffolds with suitable structural and mechanical properties for colonization with mesenchymal stem cells promoting the regeneration of defective bone tissue with the required rate of safe biodegradation will be evaluated on the basis of in vitro and in vivo tests. Their proposed composition will combine the advantages of biodegradable polylactide electrospun nanofibers, natural collagen matrix supplemented with sodium hyaluronate and natural calcium phosphate nanoparticles. The preparation process will be optimized, aiming at an interconnected and homogeneously porous material with a nano/microstructured surface, outstanding mechanical properties and a controlled rate of biodegradation capable of withstanding dynamic culture conditions and encouraging homogeneous mesenchymal stem cell (MSC) colonization. This will be tested in vitro, and the acquired knowledge will be transferred to in vivo experiments with miniature pigs.

• MeSH
• fosforečnany vápenaté terapeutické užití   MeSH
• kolagen terapeutické užití   MeSH
• mezenchymální kmenové buňky MeSH
• nanokompozity MeSH
• polyestery terapeutické užití   MeSH
• regenerace kostí MeSH
• testování materiálů MeSH
• vstřebatelné implantáty MeSH

• Konspekt
• Ortopedie. Chirurgie. Oftalmologie
• NLK Obory
• ortopedie
• technika lékařská, zdravotnický materiál a protetika
• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

The excellent mechanical, tribological and biochemical properties of diamond coatings are promising for improving orthopedic or stomatology implants. A crucial prerequisite for such applications is an understanding and control of the biological response of the diamond coatings. This study concentrates on the correlation of diamond surface properties with osteoblast behavior. Nanocrystalline diamond (NCD) films (grain size up to 200 nm, surface roughness 20 nm) were deposited on silicon substrates of varying roughnesses (1, 270 and 500 nm) and treated by oxygen plasma to generate a hydrophilic surface. Atomic force microscopy was used for topographical characterization of the films. As a reference surface, tissue culture polystyrene (PS) was used. Scanning electron microscopy and immunofluorescence staining was used to visualize cell morphological features as a function of culture time. Metabolic activity, alkaline phosphatase activity, and calcium and phosphate deposition was also monitored. The results show an enhanced osteoblast adhesion as well as increased differentiation (raised alkaline phosphatase activity and mineral deposition) on NCD surfaces (most significantly on RMS 20 nm) compared to PS. This is attributed mainly to the specific surface topography as well as to the biocompatible properties of diamond. Hence the controlled (topographically structured) diamond coating of various substrates is promising for preparation of better implants, which offer faster colonization by specific cells as well as longer-term stability.

• MeSH
• biokompatibilní materiály chemie   MeSH
• buněčná diferenciace MeSH
• buněčné kultury metody   MeSH
• buněčné linie MeSH
• diamant chemie   MeSH
• lidé MeSH
• molekulární konformace MeSH
• nanostruktury chemie   ultrastruktura   MeSH
• osteoblasty cytologie   fyziologie   MeSH
• osteogeneze fyziologie   MeSH
• povrchové vlastnosti MeSH
• proliferace buněk MeSH
• tkáňové inženýrství metody   MeSH
• velikost buňky MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH

Vaccinia virus (VV) is considered to cause lytic infection of most cells, with lysis being regarded equivalent to necrosis. Activation of caspases has not been associated with necrosis. However, we observed the activation and activity of caspases in epithelial cells HeLa G and BSC-40 lytically infected with VV. Using three different flow-cytometric approaches, we characterized the distinct stages of caspase cascade in VV-infected cells: a cleaved, activated form of caspases detected using a fluorescent pan-caspase inhibitor; caspase activity assayed by cleavage of a non-fluorescent substrate into a fluorescent product; caspase-specific cleavage of death substrates characterized by a fluorescent antibody detecting a neo-epitope in cytokeratin-18. All of these approaches yielded an increased fluorescent signal in VV-infected cells compared to mock-infected controls. Additionally, the signal was decreased by the expression of Bcl-2. The cleavage of cytokeratin-18 was confirmed by western blotting, but another key protein involved in apoptosis, PARP, was not cleaved in VV-infected lytic cells. The necrotic phenotype of the cells was confirmed by increased cell membrane permeability and/or decreased mitochondrial membrane potential. In conclusion, our data suggest that VV infection of the epithelial cells HeLa G and BSC-40 initiates the apoptotic program, however, apoptosis is not completed and switches into necrosis.

• MeSH
• aktiny genetika   metabolismus   MeSH
• aktivace enzymů MeSH
• apoptóza MeSH
• Cercopithecus aethiops MeSH
• cytopatogenní efekt virový MeSH
• epitelové buňky cytologie   fyziologie   virologie   MeSH
• fenotyp MeSH
• financování organizované MeSH
• HeLa buňky MeSH
• kaspasy genetika   metabolismus   MeSH
• keratin-18 genetika   metabolismus   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nekróza MeSH
• permeabilita buněčné membrány MeSH
• poly(ADP-ribosa)polymerasy genetika   metabolismus   MeSH
• protoonkogenní proteiny c-bcl-2 genetika   metabolismus   MeSH
• vakcínie patofyziologie   virologie   MeSH
• virus vakcinie fyziologie   růst a vývoj   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH