Nanostructure
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The review intends to overview a wide range of nanostructured natural, synthetic and biological membrane implants for tissue engineering to help in retinal degenerative diseases. Herein, we discuss the transplantation strategies and the new development of material in combination with cells such as induced pluripotent stem cells (iPSC), mature retinal cells, adult stem cells, retinal progenitors, fetal retinal cells, or retinal pigment epithelial (RPE) sheets, etc. to be delivered into the subretinal space. Retinitis pigmentosa and age-related macular degeneration (AMD) are the most common retinal diseases resulting in vision impairment or blindness by permanent loss in photoreceptor cells. Currently, there are no therapies that can repair permanent vision loss, and the available treatments can only delay the advancement of retinal degeneration. The delivery of cell-based nanostructure scaffolds has been presented to enrich cell survival and direct cell differentiation in a range of retinal degenerative models. In this review, we sum up the research findings on different types of nanostructure scaffolds/substrate or material-based implants, with or without cells, used to deliver into the subretinal space for retinal diseases. Though, clinical and pre-clinical trials are still needed for these transplants to be used as a clinical treatment method for retinal degeneration.
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Heat-induced antigen retrieval (HIAR) treatment improves the antigen immunodetection in formalin-fixed, paraffin-embedded tissue samples and it can also improve the detection of intracellular antigens in alcohol-fixed cytological samples, although it could deleteriously impact immunodetection, particularly that of membranous antigens. We examined the differences in cell surface topography on MCF7 cells fixed in methanol/acetone (M/A) or 4% paraformaldehyde (4% PFA), as well as the changes caused by HIAR treatment at three different temperatures (60, 90, and 120°C), using atomic force microscopy. Furthermore, the consequences for immunostaining of five membranous antigens [epidermal growth factor receptor (EGFR), E-cadherin, CD9, CD24, and CD44] were examined. Our results illustrate that while there was no one single optimal immunostaining condition for the tested antibodies, the surface topography could be an important factor in successful staining. Generally, the best conditions for successful immunostaining were M/A fixation with no HIAR treatment, whereas in 4% PFA-fixed cells, HIAR treatment at 120°C was optimal. These conditions showed similarity in cell surface skewness. A correlation factor between successful immunocytochemical staining and the skewness parameter was 0.8000. Our results indicate that the presence of valleys, depressions, scratches, and pits on the cell surface is unfavorable for the successful immunodetection of cell surface antigens.
- MeSH
- antigeny povrchové analýza MeSH
- buněčná membrána účinky záření ultrastruktura MeSH
- lidé MeSH
- MFC-7 buňky MeSH
- mikroskopie atomárních sil MeSH
- nanostruktury * MeSH
- povrchové vlastnosti * MeSH
- vysoká teplota * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This review deals with the main characteristics of modern nanostructures like Au nanoparticles or C nanotubes and the great potential of their application in biosensor manufacture. The principles of biosensing are also mentioned, focusing on the label-free electrochemical detection using self-assembled monolayers on Au surfaces. This review deals mostly with biosensors for use in clinical chemistry and diagnostics as immunosensors. Application of nanoparticles can improve electrode transduction although antigens and antibodies do not form a redox couple.
In this study, CeO2 (cerium oxide) nanoparticles were synthesized using Pinus halepensis pollen and were characterized by field emission scanning electron microscopy (FESEM), powder X-ray diffraction (PXRD) and Raman spectroscopy. The results showed that the ensuing CeO2 nanostructures, ranging in size from 5 to 25 nm, had high porosity. Synthesized CeO2 showed the effective catalytic activity towards the photocatalytic removal of dyes. In this work, the photocatalytic activity to removal dye (methyl violet 2B), in the absence of UV radiation, using cerium dioxide nanoparticles (CeO2-NP) was determined. In this research, four main factors such as effect on color, concentration and pH were examined and maximum %R was obtained about was 97% in 75 min in presence of 50 mg of hydrogen peroxide.
- MeSH
- barvicí látky chemie izolace a purifikace MeSH
- borovice MeSH
- cer chemie MeSH
- nanostruktury chemie MeSH
- poréznost MeSH
- Publikační typ
- časopisecké články MeSH
elektronický časopis
ECM is composed of different collagenous and non-collagenous proteins. Collagen nanofibers play a dominant role in maintaining the biological and structural integrity of various tissues and organs, including bone, skin, tendon, blood vessels, and cartilage. Artificial collagen nanofibers are increasingly significant in numerous tissue engineering applications and seem to be ideal scaffolds for cell growth and proliferation. The modern tissue engineering task is to develop three-dimensional scaffolds of appropriate biological and biomechanical properties, at the same time mimicking the natural extracellular matrix and promoting tissue regeneration. Furthermore, it should be biodegradable, bioresorbable and non-inflammatory, should provide sufficient nutrient supply and have appropriate viscoelasticity and strength. Attributed to collagen features mentioned above, collagen fibers represent an obvious appropriate material for tissue engineering scaffolds. The aim of this minireview is, besides encapsulation of the basic biochemical and biophysical properties of collagen, to summarize the most promising modern methods and technologies for production of collagen nanofibers and scaffolds for artificial tissue development.
- MeSH
- cytoskelet chemie MeSH
- extracelulární matrix - proteiny chemie MeSH
- extracelulární matrix chemie MeSH
- kolagen chemie MeSH
- lidé MeSH
- mechanický stres MeSH
- nanostruktury * MeSH
- pružnost MeSH
- testování materiálů MeSH
- tkáňové inženýrství * MeSH
- tkáňové podpůrné struktury * MeSH
- viskozita MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
This review aims to summarize the current status of photoactivatable nanostructured film and polymeric nanofiber surfaces used in biomedical applications with emphasis on their photoantimicrobial activity, oxygen-sensing in biological media, light-triggered release of drugs, and physical or structural transformations. Many light-responsive functions have been considered as novel ways to alter surfaces, i.e., in terms of their reactivities and structures. We describe the design of surfaces, nano/micro-fabrication, the properties affected by light, and the application principles. Additionally, we compare the various approaches reported in the literature.
- MeSH
- fotochemie * MeSH
- nanostruktury * MeSH
- povrchové vlastnosti MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
The role of pigments in generating the colour and maculation of birds' eggs is well characterized, whereas the effects of the eggshell's nanostructure on the visual appearance of eggs are little studied. Here, we examined the nanostructural basis of glossiness of tinamou eggs. Tinamou eggs are well known for their glossy appearance, but the underlying mechanism responsible for this optical effect is unclear. Using experimental manipulations in conjunction with angle-resolved spectrophotometry, scanning electron microscopy, atomic force microscopy and chemical analyses, we show that the glossy appearance of tinamou eggshells is produced by an extremely smooth cuticle, composed of calcium carbonate, calcium phosphate and, potentially, organic compounds such as proteins and pigments. Optical calculations corroborate surface smoothness as the main factor producing gloss. Furthermore, we reveal the presence of weak iridescence on eggs of the great tinamou (Tinamus major), an optical effect never previously documented for bird eggs. These data highlight the need for further exploration into the nanostructural mechanisms for the production of colour and other optical effects of avian eggshells.
- MeSH
- fosforečnany vápenaté metabolismus MeSH
- nanostruktury ultrastruktura MeSH
- ovum * metabolismus ultrastruktura MeSH
- pigmentace fyziologie MeSH
- ptáci MeSH
- uhličitan vápenatý metabolismus MeSH
- vaječné proteiny metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
Two approaches to polymer surface nanostructuring by laser beam are discussed: (i) exposure of surface to a polarized excimer laser beam and (ii) scanning of doped polymer surface by a semiconductor laser. The effect of laser fluence, the angle of incident laser beam and its wavelength on the nanostructure formation is described. Nanostructured polymers are used as substrates for deposition of Au nanolayers and biocompatibility studies. The properties of deposited Au nanolayers are significantly influenced by surface structure and chemical nature of the used substrate. Polymer films doped with porphyrin were irradiated with laser and simultaneously mechanically scanned. By combination of these two techniques a regular periodic pattern was formed. The structural properties depend on scanning rate and laser intensity. Nanostructured polymer surfaces are promising substrates in electronics, optics and tissue engineering.
- Klíčová slova
- laserový svazek, interakce,
- MeSH
- biokompatibilní materiály MeSH
- biopolymery terapeutické užití MeSH
- buněčné kultury MeSH
- lasery využití MeSH
- nanostruktury MeSH
- nanotechnologie MeSH
- polymery terapeutické užití MeSH
- povrchové vlastnosti MeSH
- tkáňové inženýrství MeSH
- tkáňové podpůrné struktury MeSH
- Publikační typ
- práce podpořená grantem 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
