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Use of nanofluidic mixing for preparation of liposome carriers stained by gadolinium for contrast imaging by magnetic resonance (MRI)
Velínská, Kamila ; Mašek,, Josef (referee) ; Turánek, Jaroslav (advisor)
This diploma thesis focuses on the preparation of the liposomes, containing lipids with gadolinium, which are used for a contrast magnetic resonance imaging. The liposomes were prepared by the lipid film hydration followed by an extrusion and also by a new nanofluid mixing method on the NanoAssemblr Benchtop. The preparation technology has been optimized for parameters such as the composition of lipids, the flow rate ratio and total flow rate. The method of modification of the liposomes surface by gadolinium complexes has been developed. This method is using a conjugation reaction between the lipids containing cyanuric acid and Gd-DOTA. Prepared Gd-liposomes, which contain gadolinium, were complexly defined by the characterization techniques of DLS and NTA. The morphology of liposomes was observed by TEM and cryo-TEM. Methods for the determination of phospholipid content (Stewart test) and residual water in the lyophylisates of liposomes (Karl-Fischer titration) were used. Gadolinium in liposomal preparations was determined by ICP-OES. Using MR, the concept of gadolinium liposomes was verified and designed for MRI imaging of thrombi. The concept describing the mechanism of liposomes formation based on the experimentally proven existence of a phospholipid bilayer fragment has been developed. This concept is based on the experimentally proven existence of a phospholipid bilayer fragment.
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Detection of luminescent nanoparticles in plants by laser spectroscopy
Střítežská, Sára ; Novotný,, Karel (referee) ; Modlitbová, Pavlína (advisor)
This diploma thesis deals with evaluation of toxicity and bioaccumulation of photon-upconversion nanoparticles (UCNPs) in model plant maize (Zea mays). Lanthanide-doped UCNPs with different composition and size were tested in three different concentrations in this work. The exposure took place for 168 hours. Toxicity was assessed based on four macroscopic toxicological endpoints (mortality, the length of belowground part of the plants, the length of aboveground part of the plants and whole plants length). Spatial distribution of elements yttrium, ytterbium, erbium and gadolinium in model plants was determined using laser induced breakdown spectroscopy with spatial resolution of 100 m and 26 m. Distribution of UCNPs in plants was further studied with photon-upconversion microscanning with spatial resolution of 40 m. Stability of UCNPs during and after the plant exposure was also discussed in this thesis.
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Nuclear Fuel in Operational Conditions
Konopová, Tamara ; Novotný, Filip (referee) ; Katovský, Karel (advisor)
This thesis deals with the issue of nuclear fuel. Firstly, the problem of nuclear fuel in the implementation for certain reactors is presented. Production of nuclear fuel is introduced, which includes the performance of companies engaged in the production of this fuel. Secondly, the phenomena in the fuel burnup are discussed. Lastly, the burnable absorbers are mentioned and the analysis of burnable absorbers is carried out.
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MRI Acquisition and Preprocessing of Image Sequences for Clinical Perfusion Imaging
Krchňavý, Jan ; Bartoš, Michal (referee) ; Jiřík, Radovan (advisor)
This thesis describes the theory for static and dynamic magnetic-resonance imaging using contrast agents affecting T1 relaxation time. The available acquisition methods in the specified facility of Masaryk Oncological Institute in Brno are described. The sequences for subsequent experimental measurements are selected. The used phantoms are described. Acquisition protocol for measuring is described briefly and the evaluation method for the measured data is suggested. The best acquisition sequence and a method of measurements is chosen influenced by estimation of relaxation time T1, sensitivity and signal to noise ratio. Perfusion analysis is executed and perfusion parameters are calculated. The work was supported by the European Regional Development Fund and the State Budget of the Czech Republic (RECAMO, CZ.1.05/2.1.00/03.0101).
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Nuclear Fuel in Operational Conditions
Konopová, Tamara ; Novotný, Filip (referee) ; Katovský, Karel (advisor)
This thesis deals with the issue of nuclear fuel. Firstly, the problem of nuclear fuel in the implementation for pressurized water reactors is presented. Production of nuclear fuel is introduced, which includes the performance of companies engaged in the production of this fuel. Secondly, problems of nuclear fuel during operation, focusing on burnable absorbers and phenomena in the fuel burnup are discussed. Lastly, the calculation is carried out and gadolinium as a burnable absorber is compared with erbium as a burnable absorber.
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Thermal lens spectrometric detection of MRI contrast agents in the process of their photocatalytic degradation
Petruľák, Michal ; Řezáčová, Veronika (referee) ; Franko, Mladen (advisor)
Diplomová práce je zaměřena na studium degradace kontrastních látek pro magnetickou rezonanci. Tyto látky se dnes ve velké míře používají v oblastech s rozvinutým zdravotnictvím. Můžeme je najít v odtocích z čistíren odpadních vod, což svědčí o tom, že běžné stupně čištění odpadních vod nejsou dostatečně efektivní pro jejich odstranění. O degradaci kontrastních látek na bázi gadolinia je jen málo informací. Fotokatalytický rozklad za pomoci oxidu titaničitého a také ozonace vybrané kontrastní látky gadobutrolu, byl sledován pomocí měření celkového organického uhlíku, mikroskopie termálních čoček a spektrofotometrie.
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Detection of luminescent nanoparticles in plants by laser spectroscopy
Střítežská, Sára ; Novotný,, Karel (referee) ; Modlitbová, Pavlína (advisor)
This diploma thesis deals with evaluation of toxicity and bioaccumulation of photon-upconversion nanoparticles (UCNPs) in model plant maize (Zea mays). Lanthanide-doped UCNPs with different composition and size were tested in three different concentrations in this work. The exposure took place for 168 hours. Toxicity was assessed based on four macroscopic toxicological endpoints (mortality, the length of belowground part of the plants, the length of aboveground part of the plants and whole plants length). Spatial distribution of elements yttrium, ytterbium, erbium and gadolinium in model plants was determined using laser induced breakdown spectroscopy with spatial resolution of 100 m and 26 m. Distribution of UCNPs in plants was further studied with photon-upconversion microscanning with spatial resolution of 40 m. Stability of UCNPs during and after the plant exposure was also discussed in this thesis.
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MRI contrast agents for angiography
Urbanovský, Peter ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
Modern diagnostic method magnetic resonance imaging (MRI) usually uses contrast agents T1-type, which are based on Gd3+ complexes. Due to severe toxicity of free Gd3+ , it is desired to have thermodynamically stable and kinetically inert complexes with fast elimination from the body. This work summarizes information about a novel contrast agent based on ligand DO3AP (1,4,7,10-tetraazacyclododecane-1-methyl(alkyl)phosphinic-4,7,10- triacetic acid) with pendant hydrophobic dibenzylamino group which is able to interact hydrophobically with the macromolecule of serum albumin. The stability of supracomplex is dependent on pH value, i.e. on the protonation of the pendant amino group of the complex (pKA = 5.6) and this interaction was confirmed from 1 H-NMRD profile and fluorescent analysis. The compound was tested for its angiographic properties in vivo on rat model. Furthermore, other complexes of the ligand with trivalent lanthanides (Nd3+ , Eu3+ , Tb3+ , Dy3+ , Er3+ ) were characterized by various methods (XRD, luminescence, UV-VIS, 1 H-, 17 O- and 31 P-NMR). The cleavage of the benzyl groups affords ligand whose Ln3+ complexes possess pH dependent PARACEST effect. These complexes were characterized by XRD, luminescence and 1 H- and 31 P-NMR. Moreover, the novel ligands with modified length of pendant...
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New ligands for magnetic resonance imaging - pH-resposive contrast agents
Urbanovský, Peter ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
Fast spread of MRI technique has brought new demands for MRI contrast agents. They are required to be nontoxic, kinetically inert, thermodynamically stable, biologically inactive complexes Gd(III) with high relaxivity (the ability of magnetic compounds to increase the relaxation rates of the surrounding water proton spins), removable from body in unchanged form. This bachelor thesis resumes basic theory for contrast agents, synthesis of new ligand and its Gd(III) complex coordinating one molecule of water and with ability of the non-covalent interaction of benzylic group with serum albumine resulting in increase in relaxivity. Luminiscence were measured for Eu(III) and Tb(III) complexes and relaxivity of Gd(III) complex in and without the presence of bovine serum albumine in vitro. The novel contrast agent was tested in vivo on rat model. Keywords MRI, gadolinium, macrocyclic ligands, macrocyclic complexes
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Use of nanofluidic mixing for preparation of liposome carriers stained by gadolinium for contrast imaging by magnetic resonance (MRI)
Velínská, Kamila ; Mašek,, Josef (referee) ; Turánek, Jaroslav (advisor)
This diploma thesis focuses on the preparation of the liposomes, containing lipids with gadolinium, which are used for a contrast magnetic resonance imaging. The liposomes were prepared by the lipid film hydration followed by an extrusion and also by a new nanofluid mixing method on the NanoAssemblr Benchtop. The preparation technology has been optimized for parameters such as the composition of lipids, the flow rate ratio and total flow rate. The method of modification of the liposomes surface by gadolinium complexes has been developed. This method is using a conjugation reaction between the lipids containing cyanuric acid and Gd-DOTA. Prepared Gd-liposomes, which contain gadolinium, were complexly defined by the characterization techniques of DLS and NTA. The morphology of liposomes was observed by TEM and cryo-TEM. Methods for the determination of phospholipid content (Stewart test) and residual water in the lyophylisates of liposomes (Karl-Fischer titration) were used. Gadolinium in liposomal preparations was determined by ICP-OES. Using MR, the concept of gadolinium liposomes was verified and designed for MRI imaging of thrombi. The concept describing the mechanism of liposomes formation based on the experimentally proven existence of a phospholipid bilayer fragment has been developed. This concept is based on the experimentally proven existence of a phospholipid bilayer fragment.
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