Tissue transparency Dotaz Zobrazit nápovědu
Our goal was to find an optimal tissue clearing protocol for whole-mount imaging of embryonic and adult hearts and whole embryos of transgenic mice that would preserve green fluorescent protein GFP fluorescence and permit comparison of different currently available 3D imaging modalities. We tested various published organic solvent- or water-based clearing protocols intended to preserve GFP fluorescence in central nervous system: tetrahydrofuran dehydration and dibenzylether protocol (DBE), SCALE, CLARITY, and CUBIC and evaluated their ability to render hearts and whole embryos transparent. DBE clearing protocol did not preserve GFP fluorescence; in addition, DBE caused considerable tissue-shrinking artifacts compared to the gold standard BABB protocol. The CLARITY method considerably improved tissue transparency at later stages, but also decreased GFP fluorescence intensity. The SCALE clearing resulted in sufficient tissue transparency up to ED12.5; at later stages the useful depth of imaging was limited by tissue light scattering. The best method for the cardiac specimens proved to be the CUBIC protocol, which preserved GFP fluorescence well, and cleared the specimens sufficiently even at the adult stages. In addition, CUBIC decolorized the blood and myocardium by removing tissue iron. Good 3D renderings of whole fetal hearts and embryos were obtained with optical projection tomography and selective plane illumination microscopy, although at resolutions lower than with a confocal microscope. Comparison of five tissue clearing protocols and three imaging methods for study of GFP mouse embryos and hearts shows that the optimal method depends on stage and level of detail required.
- Klíčová slova
- Confocal microscopy, Embryo, Green fluorescent protein (GFP), Heart, Optical projection tomography, Tissue transparency,
- MeSH
- myši transgenní MeSH
- myši MeSH
- srdce embryologie MeSH
- zelené fluorescenční proteiny analýza biosyntéza genetika MeSH
- zobrazování trojrozměrné metody MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- Názvy látek
- zelené fluorescenční proteiny MeSH
Nanocellulose is cellulose in the form of nanostructures, i.e., features not exceeding 100 nm at least in one dimension. These nanostructures include nanofibrils, found in bacterial cellulose; nanofibers, present particularly in electrospun matrices; and nanowhiskers, nanocrystals, nanorods, and nanoballs. These structures can be further assembled into bigger two-dimensional (2D) and three-dimensional (3D) nano-, micro-, and macro-structures, such as nanoplatelets, membranes, films, microparticles, and porous macroscopic matrices. There are four main sources of nanocellulose: bacteria (Gluconacetobacter), plants (trees, shrubs, herbs), algae (Cladophora), and animals (Tunicata). Nanocellulose has emerged for a wide range of industrial, technology, and biomedical applications, namely for adsorption, ultrafiltration, packaging, conservation of historical artifacts, thermal insulation and fire retardation, energy extraction and storage, acoustics, sensorics, controlled drug delivery, and particularly for tissue engineering. Nanocellulose is promising for use in scaffolds for engineering of blood vessels, neural tissue, bone, cartilage, liver, adipose tissue, urethra and dura mater, for repairing connective tissue and congenital heart defects, and for constructing contact lenses and protective barriers. This review is focused on applications of nanocellulose in skin tissue engineering and wound healing as a scaffold for cell growth, for delivering cells into wounds, and as a material for advanced wound dressings coupled with drug delivery, transparency and sensorics. Potential cytotoxicity and immunogenicity of nanocellulose are also discussed.
PURPOSE: The goal of our study is to find an optimal approach to the preparation and preservation of corneal stromal tissue. We want to compare different methods of corneal stromal tissue creation and storage to optimize the efficacy of this process under the conditions of an eye bank. After we find the most suitable method to create a safe high quality product, we want to prove the possibility of using a single donor cornea for more than one patient. We would also like to verify the feasibility of making more corneal lenticules after the removal of a corneal endothelium for DMEK transplantation. METHODS: We provided morphological (histology, scanning electron microscope) and microbiological analysis in order to compare different methods of corneal lenticule and corneal stromal lamellae preparation and preservation. We also tested the surgical handling of the tissue to secure a safe manipulation of the tissue for clinical use. We compared two methods of corneal lenticule preparation: microkeratome dissection and femtosecond laser. As methods of preservation, we tested hypothermia, cryopreservation at -80 degrees Celsius in DMSO (dimethyl sulfoxide) and storage at room temperature with glycerol. Some intrastromal lenticules and lamellae in each group were previously irradiated with gamma radiation of 25 kGy (KiloGray). RESULTS: Corneal stromal lamellae prepared with a microkeratome have a smoother cut - side surface compared to lamellae prepared with a femtosecond laser. Femtosecond laser preparation caused more irregularities on the surface and we detected more conglomerates of the fibrils, while lamellae made with microkeratome had more sparse network. Using femtosecond laser, we were able to make more than five lenticules from a single donor cornea. Gamma irradiation led to damage of collagen fibrils in corneal stroma and a loss of their regular arrangement. Corneal tissue stored in glycerol showed collagen fibril aggregates and empty spaces between fibrils caused by dehydration. Cryopreserved tissue without previous gamma irradiation showed the most regular structure of the fibrils comparable to storage in hypothermia. CONCLUSION: Our results suggest that formation of a corneal lenticule lamellae by microkeratome results in smoother corneal lenticules, while being much cheaper than formation by femtosecond laser. Gamma irradiation of 25 kGy caused damage of the collagen fibres as well as their network arrangement, which correlated with loss of transparency and stiffer structure. These changes impair possible surgical utilisation of gamma irradiated corneas. Storage in glycerol at room temperature and cryopreservation had similar outcomes and we believe that both methods are appropriate and safe for further clinical use .
- Klíčová slova
- Corneal lenticule implantation, Corneal stromal lamella, Corneal tissue cryopreservation, Corneal tissue gamma-irradiation, Corneal tissue preparation, Effective corneal tissue utilization,
- MeSH
- dimethylsulfoxid MeSH
- glycerol * MeSH
- hypotermie * MeSH
- kolagen MeSH
- lidé MeSH
- rohovka chirurgie MeSH
- stroma rohovky chirurgie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- dimethylsulfoxid MeSH
- glycerol * MeSH
- kolagen MeSH
In experimental infection of sheep with Taenia saginata eggs the intensity of infection may be influenced by the age of the animal at the time of infection, the height of the infection dose and the mode of infection (perorally in capsules or by means of an oesophagus tube). In non-adequate intermediate hosts of T. saginata (sheep, goats), the cellular reaction around the young cysticercus is very strong, but it differs from the reaction known in bovine cysticercosis: large macrophages, which migrate to the larva at the early phase of infection in cattle, are lacking in sheep and goats. Neither the new formation of collagen in the granulation tissue was observed in these hosts, but the demarcation of the mode was formed by a wide zone of connective tissue at the periphery. The development of the cysticercus was markedly retarded and already four weeks after infection a majority of cysticerci were dead. Nodular changes persisted still 40 days p.i., when the cysts are transparent in cattle. Neither cysticerci nor their remnants were found at that time. The results of indirect haemagglutination reaction are not constant in inadequate intermediate hosts (particularly in sheep) and only low titres of antibodies can be detected even in strong infections.
meso-methyl-BODIPY photocages release a leaving group upon visible light irradiation but often lack thermal stability. In turn, our thermally-stable, red-shifted BODIPY phototether allows oligonucleotide cyclization, preventing complementary strand hybridization. Hybridization resumes upon red-NIR irradiation, disconnecting the phototether by oxidative cleavage, which is easily monitored by a blue shift in fluorescence.
- Publikační typ
- časopisecké články MeSH
Surgical experience with 2959 allogeneic and xenogeneic dense connective tissue grafts (1767 of fascia lata, 909 of pericardium, and 283 of dura mater), used in 2665 neurosurgical operations performed in the course of 20 years (1976 to 1995) is reported. Duraplasty using either allogeneic or xenogeneic grafts has had a similar, and favourable clinical outcome. Nevertheless, the pliable deep frozen fascia lata grafts, which could be used in any location, have been reserved for sella turcica plugging, anterior cranial base plasty, aneurysmal wrapping, and surgery of lipomyelomeningocele. Pericardium and dura mater grafts were in the majority of cases used over the brain convexity and posterior cranial fossa. Ovine pericardium proved to be superior to bovine and allogeneic pericardia because of its workability, flexibility, reduced thickness, and better transparency. Postsurgical complications occurred in 7.3%, and they were: 1) cerebrospinal fluid fistulas in 2.8%; 2) meningites in 2.3% (aseptic 1.4%, bacterial 0.8%, and tumoural 0.1% meningites); 3) pseudomeningoceles in 2.2%; 4) wound infections in 0.6%; 5) malresorptive hydrocephalus in 0.5%; and 6) adhesions to nerve tissue in 0.5%. The majority of complications healed without surgery. Forty-eight grafts (1.6%) failed to fulfil the requirements of the surgeon, and 46 of them were re-operated upon. Though another thirty-nine grafts healed successfully, 39 shunts (1.5%) had to be performed for malresorptive hydrocephalus (0.9%), and/or for a big pseudomeningocele (0.6%). So, the pure complication rate in 2665 duraplasties was 3.1%. The complex evaluation of the allogeneic and xenogeneic grafts (fascia, pericardium, and dura mater), used for duraplasty in neurosurgery during the last 20 years proved them, as remarkably good, with a success rates of 96.9%.
- MeSH
- časové faktory MeSH
- dítě MeSH
- dospělí MeSH
- dura mater chirurgie ultrastruktura MeSH
- elektronová mikroskopie MeSH
- fascia lata chirurgie ultrastruktura MeSH
- homologní transplantace * MeSH
- lidé MeSH
- neurochirurgie MeSH
- perikard chirurgie ultrastruktura MeSH
- pojivová tkáň chirurgie MeSH
- transplantace heterologní * MeSH
- výsledek terapie MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
- MeSH
- biochemická analýza krve MeSH
- injekce intravenózní MeSH
- izotopy vápníku analýza MeSH
- komorová voda analýza MeSH
- králíci MeSH
- oči analýza MeSH
- oční čočka analýza MeSH
- rohovka analýza MeSH
- sklivec analýza MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- izotopy vápníku MeSH
The authors proved, based on electron microscopic analysis that the vitreous body of the rabbit creates under physiological conditions a regular network of collagenous fibrils with a different cell population. The cells can be divided into three basic types: 1. Large cells with a lobular nucleus and well differentiated cytoplasm and multiple organelles which ensure a high metabolic activity. 2. The second type are cells of an elongated shape with an oval nucleus surrounded by a thin layer of cytoplasm with a small amount of organelles. 3. The third type are large globular cells with a homogeneous structureless mass. The basic cytoplasm with the nucleus and a negligible amount of organelles is pushed to the cell surface and thus forms a thin layer beneath the plasmalemma. Contrary to the pathologically altered vitreous body, the authors did not detect on the sound vitreous body any phagocytosing cells. On the other hand, the long-term effect of copper in experimental chalcosis markedly alters the cytological character of the structure of the vitreous body. Cell types typical for a sound vitreous body were not found in the affected eye in chalcosis. In addition to rare destroyed cells containing autophagosomes of varying size with incomplete plasmalemma at some sites there is the important finding of two different forms of phagocytes in the pathological vitreous body: 1. Neutrophil granulocytes and 2. Macrophages containing large phagosomes in the cytoplasm. Their function is to eliminate destroyed tissues and engulfing of copper particles.
- MeSH
- králíci MeSH
- měď metabolismus MeSH
- oční nemoci metabolismus patologie MeSH
- sklivec ultrastruktura MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- měď MeSH
INTRODUCTION: To optimize the use of nontransplantable organs in their own territory, the European Commission, as part of a project led by Italy, has promoted the use of an information technology (IT) portal, the COORENOR portal, developed by the Czech Republic in 2012, which evolved to become FOEDUS in 2015. METHODS: To evaluate the impact of the portal on our reality, we analyzed the number and type of offers received and organs imported in the previous 48 months (period A) as well as the 48 months after the introduction of the portal (period B). We also examined the origin and the offer mode. RESULTS: The offers received were 404 and 753, respectively, in the two periods, with 315 (41.8%) organs received through the portal. The organs transplanted were 53 and 64, respectively, in the two periods; 20 (31.2%) were sent through the portal. The most commonly offered organs are lungs (36.7% and 29.3% of offers in periods A and B, respectively). The most transplanted organ is the liver (59.4% and 45% of transplants in periods A and B, respectively). The use of the portal has gradually increased, growing from 16.4% of the offer mode in 2012 to 84.7% in 2016. CONCLUSIONS: The increase of offers related to the increase of donations and the attitude to the sharing of resources has determined an increase of 19.2% of total transplants, especially for certain types such as pediatric transplants. The portal, ensuring speed and simultaneity of offer, real time sharing of information and transparency of allocation, is also used for trade in the International Partnership Agreements. Therefore, transplants have been conditioned by the existing agreements with Greece, Malta, and the countries of the South Transplant Alliance.
- MeSH
- Evropská unie MeSH
- informační technologie * MeSH
- lidé MeSH
- transplantáty statistika a číselné údaje MeSH
- získávání tkání a orgánů metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Itálie MeSH
- Řecko MeSH
Ocular surface defects represent one of the most common causes of impaired vision or even blindness. For treatment, keratoplasty represents the first choice. However, if corneal defects are more extensive and associated with a limbal stem cell (LSC) deficiency, corneal transplantation is not a sufficient therapeutic procedure and only viable approach to treatment is the transplantation of LSCs. When the LSC deficiency is a bilateral disorder, autologous LSCs are not available. The use of allogeneic LSCs requires strong immunosuppression, which leads to side-effects, and the treatment is not always effective. The alternative and perspective approach to the treatment of severe ocular surface injuries and LSC deficiency is offered by the transplantation of autologous mesenchymal stem cells (MSCs). These cells can be obtained from the bone marrow or adipose tissue of the particular patient, grow well in vitro and can be transferred, using an appropriate scaffold, onto the damaged ocular surface. Here they exert beneficial effects by possible direct differentiation into corneal epithelial cells, by immunomodulatory effects and by the production of numerous trophic and growth factors. Recent experiments utilizing the therapeutic properties of MSCs in animal models with a mechanically or chemically injured ocular surface have yielded promising results and demonstrated significant corneal regeneration, improved corneal transparency and a rapid healing process associated with the restoration of vision. The use of autologous MSCs thus represents a promising therapeutic approach and offers hope for patients with severe ocular surface injuries and LSC deficiency.
- MeSH
- autologní transplantace MeSH
- biologické modely MeSH
- buněčná diferenciace MeSH
- buňky kostní dřeně cytologie metabolismus MeSH
- CD antigeny metabolismus MeSH
- kultivované buňky MeSH
- lidé MeSH
- mezenchymální kmenové buňky cytologie metabolismus MeSH
- mezibuněčné signální peptidy a proteiny metabolismus MeSH
- nanovlákna * MeSH
- nemoci rohovky chirurgie MeSH
- pohyb buněk MeSH
- transplantace kmenových buněk metody MeSH
- transplantace mezenchymálních kmenových buněk metody MeSH
- tuková tkáň cytologie metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- CD antigeny MeSH
- mezibuněčné signální peptidy a proteiny MeSH
