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Molecular mechanism of transport of plant hormone auxin into cells
Laňková, Martina ; Zažímalová, Eva (advisor) ; Stiborová, Marie (referee) ; Opatrný, Zdeněk (referee)
The non-uniform distribution of the plant growth regulator (phytohormone) auxin is known to mediate many fundamental processes in plant development. Auxin is transported through the plant body either via vascular pathways or from cell to cell by specialized polar auxin transport machinery. This machinery consists of a balanced system of passive diffusion combined with the activities of auxin influx and efflux carriers. This work is focused on the processes that are involved in the uptake of auxin into plant cells. On the basis of molecular-biological and biochemical characterization, the function as an auxin influx carrier was confirmed for PaLAX1 protein from wild cherry (Prunus avium). The sequences of isolated cDNA of the PaLAX1 gene and of its protein product are highly similar to both the cDNAs and the corresponding protein products of the AUX1/LAX-type genes, coding for putative auxin influx carriers in model plant A. thaliana. On the level of organs and single cells, we have shown that the overproduction of PaLAX1 in transgenic lines resulted in an increase of the content of native auxin indole-3-acetic acid as well as of the uptake of synthetic auxin, 2,4-dichlorophenoxyacetic acid. Further, the mechanism of action of putative auxin influx inhibitors 1-naphthoxyacetic acid (1-NOA),...
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Optimalization of Power Electric Engineering Processes by Genetic Algorithms
Paar, Martin ; Hradílek, Zdeněk (referee) ; Skala, Petr (referee) ; Toman, Petr (advisor)
Current trends in regulation of electricity supply continuity in the power engineering industry includes introduction of systems and customers standards. The electricity market liberalization in the European Union is speeded up the process furthermore. Companies included in the distribution network bussiness therefore began to be interested more in the evaluation of risks associated with the aplication of these standards. The aim of the thesis is to minimize the expenses caused by power losses of the distribution network by means of distribution network reconfiguration depending on the standard selection. For the minimization two of the Genetic algorithms was selected. As an criterion the overall expenses caused by power losses and the expenses caused by an electricity shortage. Furthermore the influence of the inclusion of the power loss to the calculation on the operation costs for given regulation standards. Two contemporary standards - finish and portugues - are considered together with three experimental standards. The aim of including experimental standards is to complete the regulation standards with parameters uncovered in the portuguese and finish standard. The results described in the thesis can be used in the distribution network optimization process from the point of reliability and operational costs.
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Recombinant vaccinia viruses used for tumor therapy; analysis of biological and biochemical features
Žůrková, Kamila
Recombinant vaccinia virus has been used for elicitation of the immune response against expressed heterologous proteins which has led to protection of the host organisms against the agents producing that antigen (viruses, cancer cells). In our laboratory, we designed and evaluated several vaccines against cancer caused by human papillomavirus type 16 (HPV16). Vaccinia viruses derived from replication competent strain P13 or attenuated MVA were used for construction of recombinant viruses expressing HPV16-E7 in highly immunogenic fusion construct SigE7LAMP. Recombinant viruses were used both in prophylactic and therapeutic settings in mouse tumor models using TC-1 or TC-1/A9 cells. The genes encoding stimulatory cytokines GM-CSF or Flt3 ligand were inserted into the above viruses to support the immune system and to potentiate the anticancer response. Tumor microenvironment was modified using the recombinant viruses expressing both the E7 gene and soluble receptor for TGF-β which should decrease the inhibition of immune system caused by tumor TGF-β cytokine and elicit the response against tumor cells. Intratumoral or intraperitoneal administration of viruses enhanced anticancer response in mice, the viruses expressing Flt3 ligand induced the proliferation of E7- specific cytotoxic T lymphocytes. The...
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Formulation of Nanoparticle Systems with Antimicrobial Agents
Brambůrková, Eva ; Dittrich, Milan (advisor) ; Podzimek, Štěpán (referee) ; Masteiková, Ruta (referee)
Drug delivery as modern way of therapeutic application is important goal of contemporary pharmaceutical research. The very specific tailor-made drug carriers and special working methods are used. Parametrs which potentially influence nanoparticle size distribution and their zeta potential were studied. Nanoparticles were prepared by emulsion solvent distribution-evaporation method from commercially available, biocompatible and biodegradable polymer PDLLA (poly (DL-lactic acid)) and other polyesters branched on mannitol or pentaerythritol and polyurethanes synthesized at workplace. Polymers were dissolved in different organic solvents (dichlormethane, chloroform or mixture of both in mass ratio 1:1). Poloxamers and polyvinylalcohol with different molecular weight and different degree of hydrolysis, polysorbate 20, and lecithin from soya bean or from eggs as emulsifying agent were used. Nanoemulsion was prepared by homogenizer with stator and rotor. Particle size and zeta potential was measured by Zetasizer. This study demonstrates that monodisperse nanoparticles can be prepared by emulsion solvent distribution-evaporation method in various composition of organic and also aqueous phase. Dispersion process is modified by organic solvent and emulsifier used. Zeta potential was influenced by composition...
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Photopolymerization
Kučera, Vladimír ; Petrůj, Jaroslav (referee) ; Kučera, František (advisor)
The bachelor thesis deals with the photochemistry of macromolecular substances, especially with photopolymerization and photocrosslinking reactions. In the theoretical section there is at first a summary of the current knowledge from the area of the general photochemistry and principles of photochemical reactions which are also applied in photopolymerization. There are also both types of photopolymerization analysed – cationic and free-radical, photocrosslinking reactions and photopolymerization applications. In the experimental part, the testing of two fotopolymerization systems was performed. In both of them, styrene was used as a monomer. In one case benzoin was used as a photoinitiator, in the second one there was benzoin ethyl ether used. Furthermore, the photoinitiation ability of these two photoinitiators was compared at the base of conversion and molecular weight of products that were synthetized at different concentrations of photoinitiators and different time periods of irradiation of the mercury lamp.
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Influence of polysaccharides on caffein absorption from beverages
Osecká, Karolína ; Márová, Ivana (referee) ; Pekař, Miloslav (advisor)
This bachelor thesis was focused on investigation of the interaction between the polysaccharide sodium hyaluronan (HA) and the alkaloid caffeine (CAF). The reason why this thesis was focused on study of aqueous solutions of hyaluronan with caffeine is that presence of polysaccharide can slow down the realising from hyalurona-caffeine complex. At first, it was determined whether the photophysical properties of caffeine reacts in different polarity solvents. Based on these results was studied the interaction of caffeine and hyaluronan using the fluorescence. Emission and excitation spectra of caffeine were observed. The HA of molecular weight of 1.7 MDa were chosen for the study of the interactions with the caffeine of concentration the caffeine contained in coffee. The results of interaction that would result to influence the emission properties of CAF, not show. In acidic solutions leading to the formation of various shapes of HA and by centrifugation it was determined whether HA in this form interacts with CAF, which was shown to decrease the absorbance of the supernatant in the CAF. The solution and the mixtures were measured in four types of environment in hydrochloric acid solutions at different pH. The influence of constant addition of caffeine and the HA of molecular weights of 1.7 MDa with different concentrations in different acidic solutions. As a part of the work was to determine how hyaluronan behaves in strongly acidic solution. And then determine the pH in model gastric juices after intake of Coca Cola and Kofola. The obtained results can be used as for description of the behavior of caffeine in the presence of selected polysaccharide.
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Quasi-parallel optimizing of simulated systems by means of genetic algorithms
Konopa, Michal ; Neruda, Roman (referee) ; Kindler, Evžen (advisor)
This work goals are SIMULA classes to model experts sessions so that each expert has his own start ideas the optimal system's parameters. All the experts are simulating the system (each expert with his own parameters), but during the simulation they are mutually exchanging information about behavior of theirs models and - in accordance with this information - they are learning, changing their own system parameters. The learning process is performed by means of genetic algorithms. The resulting optimizer is tested on concrete examples, both from the mathematical theory and real practice (e.g. optimizing of a given project). This work reassumes the dissertation of RNDR. Jiří Weinberger. CSc., who made similar type of optimizer in the 80es, when nothing concrete was known on genetic algorithms and so the experts learning scheme was modeled by techniques, which had great success in solution of real problems afterwards; but nowadays it is worth to replace them by genetic algorithms, or at least to compare both methods. Genetic algorithms are successfully used in systems optimization, where the model run is algorithmic-managed, but never in the way of directly changing the models during their running times. Parallel run of multiple simulating models on the computer equipped with only one processor requires...
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Identification of Z-linked genes for the study of sex chromosome evolution in Lepidoptera
PROVAZNÍK, Jan
Moths and butterflies (Lepidoptera) have a WZ/ZZ (female/male) sex chromosome system or its numerical variants. The non-recombining W chromosome is largely formed by heterochromatin, composed of repetitive DNA and almost free of genes. Its use for evolutionary studies is thus limited due to fast molecular divergence. Whereas the Z chromosome resembles to autosomes; it is rich in genes and thus expected to be more conserved. In this study, the Z-linked genes with available DNA sequence information are summarized in order to give reference to suitable candidates for the study on evolutionary history of sex chromosomes in Lepidoptera. The use of Zlinked genes to test current hypotheses on the origin of the lepidopteran W chromosome is also discussed.
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Antimicrobial peptides and their application into foods
Janhuba, Filip ; Petrik, Siniša (referee) ; Márová, Ivana (advisor)
The presented thesis is focused on a study of antimicrobial peptides and their potential applications into foods. Two types of antimicrobial peptides were studied in detail - bacteriocin nisin and antimicrobial enzyme lysozyme. In theoretical part an overview of antimicrobial peptides used in food industry was introduced. The experimental part of this work was focused on optimization of methods for the determination of antimicrobial peptides concentration. Commonly used spectrophotometric methods for quantitative analysis of total proteins as well as high performance liquid chromatography were tested. To determine the molecular weight and purity a modified SDS-PAGE with the addition of urea and tricine buffer was performed. Further, encapsulation of nisin into liposome was tested. Encapsulated particles were prepared by three different procedures: by ultrasonication, ethanol injection and TLE. Particles stability, distribution and size were studied by dynamic light scattering. Stability of encapsulated peptides in model conditions and model foods was studied too. Finally, antibacterial properties of the selected peptides using test system Bacillus subtilis were studied. Nisin already showed antimicrobial effect at low concentrations - about 1 µg/ml. The inhibitory effect of nisin was more evident in liquid cultures.
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