Národní úložiště šedé literatury Nalezeno 9 záznamů.  Hledání trvalo 0.01 vteřin. 
Preparation and characterisation of encapsulated biogenic nanoparticles for medical application
Poláková, Veronika ; Vojtová, Lucy (oponent) ; Brtníková, Jana (vedoucí práce)
The aim of this bachelor thesis is a preparation and polymeric encapsulation of antibacterial biogenic nanoparticles in order to enhance their stability, reduce possible cytotoxicity while maintaining antibacterial activity. The theoretical part contains an overview of regenerative medicine, commonly used nanostructures in regenerative medicine, their properties, and methods of encapsulation. The experimental work especially focuses on selenium nanoparticles synthesis using different methods with specific protecting agents followed by encapsulation via nature-inspired polymer. The used encapsulation methods are based on self-assembly polymerization and coating of selected natural polymeric adhesive. The chemical and physical properties of pure and encapsulated selenium nanoparticles, such as their concentration and morphology (size and shape) were studied using Fourier transformed infrared spectrophotometry and scanning transmission electron microscopy. It was found that different used method provides nanoparticles with different size, shape and stability. As a main result, an optimized method of selenium particles synthesis, stabilization and encapsulation was developed and described. Nanoparticles, synthesized using this method, are spherical with size ranging from 10.5 to 101 nm. The sizes of most of the synthesized nanoparticles lay within 10.5 to 40 nm interval. When encapsulated, their sizes increase and are ranging from 74.5 to 571.5 nm.
Fotostabilization of biopolymeric materials for regenerative medicine
Izsák, Dávid ; Muchová, Johana (oponent) ; Brtníková, Jana (vedoucí práce)
Non-stabilized biopolymers often show poor mechanical properties. The stabilization and improvement of these properties could be accomplished by crosslinking, but the traditionally used crosslinking agents are rather cytotoxic and harmful for the human body. The aim of this work is to find a suitable non-toxic crosslinking method that would be efficient enough, but at the same time would not represent danger to any organism. The crosslinking method developed in the presented bachelor thesis should be comparatively efficient as traditionally used methods (e.g. chemical carbodiimide-based crosslinking) as well as potentially less cytotoxic by use of naturally derived substances. The proposed alternative crosslinking method should improve the strength and stability of the crosslinked biopolymers and enhance their biological functionality. Specifically, the presented work deals with the stabilization of collagen scaffolds using vitamin important for human metabolism followed by short- and long-wavelength irradiation. The theoretical part contains a general overview of possible non-toxic crosslinking agents, describes the structure of collagen and characterizes its properties and with the properties of used vitamin as a crosslinking agent. The experimental part deals with the preparation and crosslinking optimization of collagen scaffolds. Swelling, degradation and morphology of scaffolds as well as collagen secondary structure were evaluated. As a result, sufficiently strong crosslinked scaffolds were obtained.
Mesenchymal stem cells for treatment of spinal cord injury
Dubišová, Jana ; Kubinová, Šárka (vedoucí práce) ; Hock, Miroslav (oponent)
Poranenie miechy a jeho terapia pomocou mezenchymálnych kmeňových buniek Abstrakt Pacienti s vážnym poranením miechy (SCI - spinal cord injury) majú malú šancu na plnohodnotný návrat do ich pôvodného života. Tento druh zranení necháva doživotné následky ako na samotnom pacientovi, tak aj na jeho najbližšom okolí, rodine a celosvetovo sú vydávané nemalé finančné prostriedky pre znovuzačlenenie týchto pacientov do spoločnosti. Táto práca sa zameriava na popis poranenia miechy, jeho komplikovanosť a možnosť liečby pomocou novej terapeutickej metódy mezenchymálnymi bunkami. Prvá časť pojednáva o závažnosti poranenia miechy a jeho patofyziológii s predstavením následných klinických fáz. Druhá časť je venovaná novým liečebným metódam a prístupom s dôrazom na bunkovú terapiu. Tretia časť predstaví liečebnú metódu pomocou mezenchymálnych kmeňových buniek (MSCs - mesenchymal stem cells), ktorých imunomodulačné a protizápalové vlastnosti, tak ako ich schopnosť migrácie do miesta poranenia a možnosť ich genetickej modifikácie z nich urobili skvelých kandidátov na liečbu tohto závažného poranenia. Kľúčové slová: Poranenie miechy, kmeňové bunky, mezenchymálne kmeňové bunky, bunečná terapia, regeneratívna medicína
Novel Antibacterial Collagen Scaffolds for Regenerative Medicine
Dorazilová, Jana ; Brtníková, Jana (oponent) ; Vojtová, Lucy (vedoucí práce)
This master’s thesis deals with the characterisation of 3D porous collagenous sponges enriched with selected antibacterial agents. The literature part of the thesis focuses on the overview of biomaterials and biopolymers with the emphasis on collagen and chitosan, outlines the antibacterial properties of nanoparticles and reviews current aspects of using selenium nanoparticles as an antibacterial agent. For the purpose of this work, two types of antibacterial additives were used – biopolymeric chitosan and selenium nanoparticles. Preparation of 3D porous structure was achieved using the freeze drying method. Mechanical properties of prepared biopolymeric matrices were improved by chemical crosslinking in the presence of carbodiimide. Predominantly physiochemical methods were used for characterization of prepared collagenous sponges. For microstructure analysis, pore size determination, visualisation of nanoparticles and their distribution inside the porous structure, scanning electron microscopy (SEM) with energy dispersive x ray optical analysis (EDX) was used. Parameters such as total porosity, swelling ratio, weight loss during degradation in water and enzymatic environment were evaluated by suitable gravimetric methods. Fourier transformed infrared spectroscopy with attenuated total reflectance (ATR-FTIR) was used to determine changes in the chemical structure of collagenous matrices before and after addition of the antibacterial agents. Percentage release of nanoparticles was evaluated using optical emission spectroscopy with inductively coupled plasma (ICP OES). Evaluation of antibacterial properties of tested samples was carried out mainly by the agar diffusion disk method and the macrodilution broth method. In the conducted research we were able to determine the influence of selected antibacterial additives on the physiochemical properties of 3D collagenous matrices. Their antibacterial activities showed a positive effect on bacterial inhibition of both chitosan and selenium nanoparticles with respect to their concentrations. The designed materials could be further utilized for bio medicinal applications, especially in the field of soft tissue regeneration.
Tailoring of phase composition and microstructure of calcium phosphate scaffolds applied in regenerative medicine.
Pejchalová, Lucie ; Novotná, Lenka (oponent) ; Salamon, David (vedoucí práce)
Calcium phosphates are the most used ceramic materials for bone regeneration. Calcium phosphates are biocompatible, bioactive and differ in solubility and related degradation in organism. Therefore, calcium phosphate materials are used to regenerate bone defects of small size and as coatings for metallic implants. The solubility of the used materials in body environment after implantation is determined by the ratio of individual calcium phosphates and related degradation rates. This thesis deals with the impact of shaping methods on microstructure and phase composition of calcium phosphates. Commercial hydroxyapatite powder was used as a starting ceramic powder and was treated by calcination at 800 °C for one hour. The biphasic mixture of hydroxyapatite and -tricalcium phosphate was formed during the calcination and this mixture was used for ceramic suspension preparation, with solid loading of 15 vol%, as well as for green bodies preparation. Samples were prepared using several shaping methods: freeze casting, cold isostatic pressing, uniaxial pressing, and slip-casting. Characterization of both, green bodies and sintered samples was performed and the impact of used shaping methods on microstructure and phase composition, was confirmed. It was also observed that the hydroxyapatite content is increasing with increasing porosity, and pore size. This trend applies for samples with unimodal pore size distribution as well as for samples with bimodal pore size distribution.
Immunogenicity of stem cells and their derivatives
Doležalová, Nikola ; Holáň, Vladimír (vedoucí práce) ; Kubinová, Šárka (oponent)
Imunogenicita kmenových buněk a jejich derivátů Nikola Doležalová Abstrakt Kmenové buňky mají potenciál v regenerativní medicíně především z důvodu své schopnosti diferenciovat v řadu buněčných linií a také nízké imunogenicity. Ta vyplývá mimo jiné z nízké exprese histokompatibilních antigenů a kostimulačních molekul nebo sekrece tlumivých cytokinů. Imunogenicita tkání odvozených z kmenových buněk byla v minulosti často přehlížena, ale dnes je zřejmé, že rejekce představuje nezanedbatelné riziko při jejich transplantaci. Jejich imunologickým vlastnostem je tedy věnována velká pozornost, aby bylo možné zaručit bezpečnost léčby kmenovými buňkami. Tato bakalářská práce se snaží nastínit současné poznatky o imunogenicitě kmenových buněk a jejich derivátů - zmíněny jsou jak pluripotentní kmenové buňky (embryonální a indukované pluripotentní), tak dospělé kmenové buňky (mezenchymální, limbální, neurální, hematopoetické a kmenové buňky z pupečníkové krve). Exprese imunologicky významných molekul a interakce s buňkami imunitního systému in vitro a in vivo tvoří v této práci základ pro hodnocení imunogenicity. Společně s těmito vlastnostmi budou prezentovány možné způsoby překonání imunologických bariér při transplantaci kmenových buněk. Teprve po pečlivé analýze všech těchto faktorů bude možné poznatky o kmenových...
Treatment of spinal cord injury by transplantation different types of stem cells
Dubišová, Jana ; Kubinová, Šárka (vedoucí práce) ; Cizkova, Dasa (oponent)
Poranenie miechy (SCI) je veľmi zložité poranenie s obrovskými následkami, ktoré postihujú nielen samotného pacienta, ale zmenia život aj rodinným príslušníkom a okoliu. Rovnako sa extrémne dvíhajú náklady na život takto postihnutých ľudí. Preto sa hľadá vhodná metóda, ktorá by pomohla pacientom po SCI vrátiť sa do normálneho života, alebo aspoň zmierniť následky na čo najmenšiu možnú formu. Existuje viacero medicínskych prístupov pre liečenie následkov SCI. V tejto práci sme sledovali účinky transplantácie rozličných typov kmeňových buniek, a to mezenchymálnych buniek kostnej drene (hBM-MSCs), mezenchymálnych buniek z pupočníkového tkaniva (hUC- MSCs), neurálnych prekurzorov derivovaných z indukovaných pluripotentných buniek (iPS- NPs) a neurálnych kmeňových buniek derivovaných z ľudského fetálneho tkaniva miechy (SPC- 01). Tieto bunky boli transplantované intraspinálne alebo inrtathekálne 7 dní po navodení experimentálneho modelu SCI u laboratórneho potkana. Sledovali sme expresiu génov, týkajúcich sa neurogenézy, rastových faktorov a inflamačných markerov a to v dvoch časových intervaloch, 10 a 28 dní po SCI. Naše údaje ukázali signifikantné zmeny v génovej expresií 10 dní po SCI. Signifikantne zvýšená expresia vaskulárneho endotelového rastového faktoru (Vegf), ciliárneho rastového faktoru...
Mesenchymal stem cells for treatment of spinal cord injury
Dubišová, Jana ; Kubinová, Šárka (vedoucí práce) ; Hock, Miroslav (oponent)
Poranenie miechy a jeho terapia pomocou mezenchymálnych kmeňových buniek Abstrakt Pacienti s vážnym poranením miechy (SCI - spinal cord injury) majú malú šancu na plnohodnotný návrat do ich pôvodného života. Tento druh zranení necháva doživotné následky ako na samotnom pacientovi, tak aj na jeho najbližšom okolí, rodine a celosvetovo sú vydávané nemalé finančné prostriedky pre znovuzačlenenie týchto pacientov do spoločnosti. Táto práca sa zameriava na popis poranenia miechy, jeho komplikovanosť a možnosť liečby pomocou novej terapeutickej metódy mezenchymálnymi bunkami. Prvá časť pojednáva o závažnosti poranenia miechy a jeho patofyziológii s predstavením následných klinických fáz. Druhá časť je venovaná novým liečebným metódam a prístupom s dôrazom na bunkovú terapiu. Tretia časť predstaví liečebnú metódu pomocou mezenchymálnych kmeňových buniek (MSCs - mesenchymal stem cells), ktorých imunomodulačné a protizápalové vlastnosti, tak ako ich schopnosť migrácie do miesta poranenia a možnosť ich genetickej modifikácie z nich urobili skvelých kandidátov na liečbu tohto závažného poranenia. Kľúčové slová: Poranenie miechy, kmeňové bunky, mezenchymálne kmeňové bunky, bunečná terapia, regeneratívna medicína
Polymeric nanofibrous scaffolds reinforced with diamond and ceramic nanoparticles for bone tissue engineering
Bačáková, Lucie ; Pařízek, Martin ; Staňková, Ľubica ; Novotná, Katarína ; Douglas, T.E.L. ; Brady, M. A. ; Kromka, Alexander ; Potocký, Štěpán ; Stránská, D.
Three types of nanofibrous scaffolds were prepared by electrospining: (1) poly(lactide-co-glycoside) (PLGA) scaffolds reinforced with 23 wt.% of diamond nanoparticles (DNPs), (2) poly(L-lactide) (PLLA) scaffolds with DNPs in concentration ranging from from 0.4 wt.% to 12.3 wt.%, and (3) PLLA scaffolds with 5 wt.% or 15 wt.% of hydroxyapatite (HAp) nanoparticles. The diameter of the nanofibers ranged between 160 and 729 nm. The nanofibers with nanoparticles were thicker and the void spaces among them were smaller. Mechanical properties of the nanoparticle-loaded scaffolds were better, as demonstrated by a rupture test in scaffolds with DNPs and by a creep behavior test in scaffolds with HAp. On PLGA scaffolds with DNPs, the human osteoblast-like MG-63 cells adhered in similar numbers and grew with similar kinetics as on pure PLGA scaffolds. Human bone marrow mesenchymal stem cells grew faster and reached higher population densities on PLGA-DNP scaffolds. However, on PLLA-based scaffolds, the activity of mitochondrial enzymes and concentration of osteocalcin in MG-63 cells decreased with increasing DNP concentration. On the other hand, the metabolic activity of MG-63 cells and content of osteocalcin in these cells were positively correlated with the HAp concentration in PLLA scaffolds. Thus, PLGA nanofibers with 23 wt% of DNPs and PLLA nanofibers with 5 and particularly 15 wt.% of HAp seem to be promising for bone tissue engineering.

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