surface modifications
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Titanium is commonly and successfully used in dental and orthopedic implants. However, patients still have to face the risk of implant failure due to various reasons, such as implant loosening or infection. The risk of implant loosening can be countered by optimizing the osteointegration capacity of implant materials. Implant surface modifications for structuring, roughening and biological activation in favor for osteogenic differentiation have been vastly studied. A key factor for a successful stable long-term integration is the initial cellular response to the implant material. Hence, cell-material interactions, which are dependent on the surface parameters, need to be considered in the implant design. Therefore, this review starts with an introduction to the basics of cell-material interactions as well as common surface modification techniques. Afterwards, recent research on the impact of osteogenic processes in vitro and vivo provoked by various surface modifications is reviewed and discussed, in order to give an update on currently applied and developing implant modification techniques for enhancing osteointegration.
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
AIM: In this study, we analysed the post-translational modification of receptor tyrosine kinase-like orphan receptor (Ror1). Ror1 is highly upregulated in B cells of patients with chronic lymphocytic leukaemia (CLL). Molecularly, Ror1 acts as the Wnt receptor in the non-canonical Wnt pathway. METHODS: The level of Ror1 glycosylation in HEK293 cells and in primary human CLL cells was analysed by treatment of inhibitors interfering with different steps of glycosylation process and by direct treatment of cell lysates with N-glycosidase. Ror1 ubiquitination was determined by ubiquitination assay. Functional consequences of post-translational modifications were analysed by immunohistochemistry and by analysis of cell surface proteins. Differences in Ror1 glycosylation were confirmed by analysis of 14 samples of B cells from CLL patients. RESULTS: We demonstrate that Ror1 is extensively modified by N-linked glycosylation. Glycosylation produces several variants of Ror1 with electrophoretic migration of approx. 100, 115 and 130 kDa. Inhibition of glycosylation interferes with cell surface localization of the 130-kDa variant of Ror1 and prevents Ror1-induced formation of filopodia. Moreover, we show that 130-kDa Ror1 is mono-ubiquitinated. Furthermore, individual CLL patients show striking differences in the electrophoretic migration of Ror1, which correspond to the level of glycosylation. CONCLUSION: Our data show that Ror1 undergoes complex post-translational modifications by glycosylation and mono-ubiquitination. These modifications regulate Ror1 localization and signalling, and are highly variable among individual CLL patients. These may suggest that Ror1 signals only in a subset of CLL patients despite Ror1 levels are ubiquitously high in all CLL patients.
- MeSH
- B-lymfocyty metabolismus MeSH
- CHO buňky MeSH
- chronická lymfatická leukemie metabolismus MeSH
- Cricetulus MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- glykosylace MeSH
- HEK293 buňky MeSH
- imunohistochemie MeSH
- konfokální mikroskopie MeSH
- křečci praví MeSH
- lidé MeSH
- molekulová hmotnost MeSH
- posttranslační úpravy proteinů účinky léků MeSH
- průtoková cytometrie MeSH
- pseudopodia metabolismus MeSH
- signální transdukce účinky léků MeSH
- sirotčí receptory podobné receptoru tyrosinkinasy chemie genetika metabolismus MeSH
- transfekce MeSH
- transport proteinů MeSH
- ubikvitinace MeSH
- western blotting MeSH
- zvířata MeSH
- Check Tag
- křečci praví MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Ti implants have become an important instrument in handling various problems associated with the loss of fle¬xibility of a joint system. Having replaced a damaged joint with an endoprosthesis reduces pain, restores flexibility and improves the patient's quality of life. The implant-bone integration may be a complicated and lengthy process. Therefore, the state of the material surface is of vital importance. Ti can be treated electrochemically to produce a tubular nanostructure, which can later be modified to achieve bioactivity. Moreover, the large adsorption surface enables anchoring of biologically active substances and pharmaceuticals. The nanostructure and its further modifications could facilitate and strengthen the implant-bone integration, and thus shorten the healing process. The article describes the preparation of nanostructures and summarizes the knowledge of Ti surface treatment.
- MeSH
- biokompatibilní materiály MeSH
- biomedicínský výzkum MeSH
- biotransformace MeSH
- chirurgie operační * MeSH
- integriny fyziologie MeSH
- lidé MeSH
- molekuly buněčné adheze fyziologie MeSH
- nanostruktury MeSH
- ortopedické výkony MeSH
- protézy a implantáty * MeSH
- titan * chemie terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
The nanoparticle based drugs, mostly in liposomes, are already approved for clinical use or under clinical investigation. Many attempts are made to improve nanoparticles sizes, shapes and surface modifications that lead to prolongation of drug circulation in blood stream and targeting to cancer cells. Thus small molecules like polyethylene glycol and targeting ligands like folic acid, peptides, antibodies, aptamers and nucleic acids are bound on the surface of nanoparticles with the aim to increase specific cell uptake. Very promising are multifunctional nanoparticles that combine both diagnostic as well as delivery role together.
- Klíčová slova
- stealth liposomes,
- MeSH
- apoferritiny terapeutické užití MeSH
- ferritiny terapeutické užití MeSH
- genetická terapie MeSH
- genetické vektory MeSH
- grafit MeSH
- lékové transportní systémy MeSH
- lidé MeSH
- liposomy MeSH
- magnetická rezonanční tomografie MeSH
- magnetické nanočástice chemie terapeutické užití MeSH
- magnetismus MeSH
- nádory diagnóza terapie MeSH
- nanočástice * chemie terapeutické užití MeSH
- nanomedicína MeSH
- nanotrubičky uhlíkové MeSH
- nosiče léků * chemie terapeutické užití MeSH
- protinádorové látky * chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
- MeSH
- barvicí látky chemie terapeutické užití MeSH
- citlivost dentinu etiologie terapie MeSH
- dentin chemie účinky záření ultrastruktura MeSH
- erythrosin MeSH
- extrakce zubů MeSH
- finanční podpora výzkumu jako téma MeSH
- laserová koagulace metody využití MeSH
- laserová terapie MeSH
- lasery MeSH
- lidé MeSH
- molár třetí účinky záření MeSH
- Check Tag
- lidé MeSH
Collagen is the most abundant protein in the animal and human bodies, and it is not exempt from this aging phenomenon. Some age-related changes may appear on collagen sequences, such as increased surface hydrophobicity, the appearance of post-translational modifications, and amino acids racemization. This study has shown that the protein hydrolysis under deuterium conditions is privileged to limit the natural racemization during the hydrolysis. Indeed, under the deuterium condition, the homochirality of recent collagens is preserved whose amino acids are found in their L-form. However, in aging collagen, a natural amino acid racemization was observed. These results confirmed that the % d-amino acids are progressive according to age. The collagen sequence is degraded over time, and a fifth of the sequence information is lost during aging. Post-translational modifications (PTMs) in aging collagens can be a hypothesis to explain the modification of the hydrophobicity of the protein with the decrease of hydrophilic groups and the increase of hydrophobic groups. Finally, the exact positions of d-amino acids and PTMs have been correlated and elucidated.
- MeSH
- aminokyseliny * chemie MeSH
- chromatografie kapalinová MeSH
- deuterium chemie MeSH
- kolagen MeSH
- lidé MeSH
- posttranslační úpravy proteinů MeSH
- proteomika * MeSH
- stárnutí MeSH
- tandemová hmotnostní spektrometrie metody MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- 1-fosfatidylinositol-3-kinasa genetika imunologie MeSH
- aktivace enzymů genetika imunologie MeSH
- analýza buněčné migrace metody využití MeSH
- buňky HT-29 cytologie imunologie MeSH
- cytokiny genetika imunologie MeSH
- extracelulární matrix genetika imunologie MeSH
- faktor stimulující štěpení genetika imunologie MeSH
- insulinu podobný růstový faktor I genetika imunologie MeSH
- integriny genetika imunologie MeSH
- kadheriny genetika imunologie MeSH
- kateniny genetika imunologie MeSH
- lidé MeSH
- MAP kinasový signální systém genetika imunologie MeSH
- membránové glykoproteiny genetika imunologie MeSH
- nádorové buňky kultivované cytologie imunologie MeSH
- pohyb buněk genetika imunologie MeSH
- receptory buněčného povrchu genetika imunologie MeSH
- vitronektin genetika imunologie MeSH
- Check Tag
- lidé MeSH
As the consumption of implants increases, so do the requirements for individual types of implants, for example, improved biocompatibility or longevity. Therefore, the nano-modification of the titanium surface is often chosen. The aim was to characterize the modified surface with a focus on medical applications. The titanium surface was modified by the anodic oxidation method to form nanotubes. Subsequently, the material was characterized and analyzed for medical applications-surface morphology, surface wettability, chemical composition, and release of ions into biological fluids. A human gingival fibroblasts (HGFb) cell line was used in the viability study. A homogeneous layer of nanotubes of defined dimensions was formed on the titanium surface, ensuring the material's biocompatibility-the preparation conditions influence the resulting properties of the nanostructured surface. Nanostructured titanium exhibited more suitable characteristics (e.g., wettability, roughness, ion release) for biological applications than compared to pure titanium. It was possible to understand the behavior of the modified layer on the titanium surface and its effect on cell behavior. Another contribution of this work is the combination of material characterization (ion release) with the study of cytocompatibility (direct contact of cells with metals).
- MeSH
- fibroblasty MeSH
- lidé MeSH
- nanostruktury * MeSH
- povrchové vlastnosti MeSH
- smáčivost MeSH
- titan * farmakologie chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
