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Backup power supply with solar panel charging
Křepela, Pavel ; Götthans, Tomáš (referee) ; Kubíček, Michal (advisor)
This project aims to create a backup power source with solar charging for small mobile devices (through USB connector). The charger should store power in a battery that is charged either from external power source or the solar panel. In the introduction, the work deals with the theory of solar cells and batteries. Furthermore, it described the selection of suitable components and design diagram.
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Replication and transcription of nucleolar DNA
Flusser, Michal ; Smirnov, Evgeny (advisor) ; Staněk, David (referee)
The nucleolus is the most prominent compartment of the cell nucleus and is the place where ribosomal RNAs (rRNAs) are synthesized, processed and assembled with ribosomal proteins. Although the nucleolus has been studied for decades its structural and functional organization is still unclear. In particular, the role of various types of DNA participating in the formation of nucleoli along with ribosomal genes is not understood. The present thesis summarizes the current knowledge and views on the nucleolus, focusing on the two synthetic processes, replication and transcription, in mammalian cells. Specific features of these processes in the context of nucleolar ultrastructure remains an unsolved problem of the modern molecular biology.
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Characterization of the porcine induced pluripotent stem cells
Svobodová, Eliška ; Vodička, Petr (advisor) ; Tlapáková, Tereza (referee)
Induced pluripotent stem cells (iPSCs) are the cells established by introducing several transcription factors into the somatic cells and culturing them in embryonal stem cell (ESCs) culture conditions. Factors used for the establishment of the first iPSCs are OCT3/4, SOX2, KLF4 and c-MYC. IPSCs created by these means resemble closely to the ESCs. IPS technology may be used to derive iPS cells of individual pacients and apply these cells for their treatment in the cases where the use of ESCs represents an ethical and imunological problem. Therefore, it is important to establish an appropriate animal model for the longtime safety testing of iPSCs before acceding to their medicinal aplication.
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Complexes of Cationic Porphyrins with Nucleic Acids Studied by Surface Enhanced Resonance Raman Spectroscopy
Lásková, Barbora ; Mojzeš, Peter (advisor) ; Michl, Martin (referee)
Complexes of cationic porphyrins with nucleic acids are interesting from the point of view of delivery of therapeutic oligonucleotides into cells as well as for photodynamic therapy of cancer. Diploma thesis deals with study of the complexes of cationic metalloporphyrin CuTMPyP4 with poly(dG-dC)2, where intercalation of porphyrin within polynucleotide's base pairs is supposed and with poly(dA-dT)2, poly(dA)·poly(dT), in which external groove-binding of CuTMPyP4 on the helix is assumed. The measurements were made by SERRS, RRS and absorption spectroscopies. From the time evolution of the SERRS spectra for each complex it was found, that intensity of SERRS spectra and rate of SERRS kinetics for complexes fall short of intuitive supposition about low SERRS signal and its slow increasing in the case of intercalation of porphyrin, because for complex of CuTMPyP4 with poly(dG-dC)2, the SERRS kinetic are very fast and final SERRS signal is more intense than for poly(dA-dT)2, poly(dA)·poly(dT). Comparing the SERRS and RRS spectra of the complexes it was found that SERRS spectra correspond to the porphyrin molecules released from the complexes rather that to the entire complexes. Study of various colloidal systems used for SERRS measurements revealed that SERRS signal evolves with time of exposition, namely for...
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The repair of the oxidative DNA damage and its relationship to the cytotoxic effect of the oxidants.
Havlínová, Alena ; Herink, Josef (advisor) ; Hochmann, Jiří (referee)
H2O2 is a strong oxidant and therefore affects all cell structures. Especially the oxidative damage of DNA is known as being very severe. It is considered to be contributing cause of carcinogenesis, mutagenesis and aging. Our work is focused on the relationship between cytotoxic effect of H2O2 and the repair of oxidative DNA damage caused by H2O2. We also studied the effects of epigallocatechin gallate (EGCG). Several studies have already proven its protective activity on DNA in particular concentrations. In our experiments we used the test of cytotoxicity to demonstrate the colony forming inhibition and the comet assay test which measures the number of single strand breaks (SSB) in 109 daltons of DNA. Generally we used cells of line AA8 and in one experiment also NER deficient cells of line UV-20. We found out that EGCG in concentrations of 12,5 and 25 μg/ml significantly protects the cells against cytotoxic effects of H2O2. When we followed the repair of the oxidative DNA damage, we have found that EGCG did not affect the repair of direct DNA breaks, but the repair of oxidised pyrimidines and purines was accelerated. And this acceleration is probably largely responsible for the protection against cytotoxic effect of H2O2. However, the EGCG function of free radical scavenger and iron ions chelator...
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Homegrown stereotyping: the shaping of Canadian consciousness through television broadcasting
Prosečová, Lenka ; Kolinská, Klára (advisor) ; Jindra, Miroslav (referee)
To define Canada and the Canadian nation is no easy task. From a historical perspective, Canada is a very young country: until 1949 there was no Canadian citizenship, the Canadian flag appeared as late as 1965, and it wasn't until 1967 that the Canadian national anthem could be heard. Although Canada would thereafter finally seem to have been able to establish its distinct identity in opposition to its mother country, Canadian patriotism has continued to be problematic. Despite years of efforts to form a pan-Canadian identity - characterized especially by Pierre Trudeau's attempts to institute federal bilingualism and a pan-Canadian identity rooted in liberal individualism - the existence of a self-conscious Canadian nation remains questionable. Within the Canadian Anglophone population there seems to be no unified notion of a panCanadian nation and thus no innate nationalism. Furthermore, for the rest of the world, Canada remains a mystery, an "Unknown Country."] Arthur Lismer, a member of the Group of Seven, assessed the situation as follows: "after 1919 most creative people, whether in painting, writing or music, began to have a guilty feeling that Canada was as yet unwritten, unpainted, unsung [ ... ],,2 Indeed, efforts were made to "capture" Canada in paintings, photography, in poetry and prose, in...
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Modulation of activities and expression of enzymes metabolizing ellipticine by histone deacetylase inhibitor trichostatin A
Kopejtková, Barbora
Histone deacetylase inhibitor trichostatin A (TSA) increases cytotoxicity of antineoplastic agent ellipticine to human neuroblastoma cells. Its mechanism of action has not yet been explained. One of the possible mode of action is conformational change in chromatin, which leads to changes in DNA that is more accessible to covalent modification and intercalation. The aim of this work is to study another mode of action, which can explain this phenomenon. The question is, if TSA can increase cytotoxicity of ellipticine to human neuroblastoma cells by modulation of activities and expression of cytochromes P450 and peroxidases. These enzymes are responsible for cytotoxicity of ellipticine to human neuroblastoma cells. TSA has no effect on oxidation of ellipticine mediated by cytochromes P450 leading to metabolites responsible for formation of ellipticine-DNA adducts and detoxication metabolites. TSA increases formation of ellipticine dimer, which is a detoxication metabolite, forming during its oxidation by peroxidases. TSA has no effect on activities of CYP1A1, CYP1A2, CYP3A, which significantly participate in oxidation of ellipticine. TSA modulates expression of enzymes oxidizing ellipticin in human neuroblastoma cells. TSA in the presence of ellipticine increases expression of CYP1A1 a CYP3A4 in...
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The role of actin dynamics in auxin transport
Stillerová, Lenka ; Cvrčková, Fatima (advisor) ; Schwarzerová, Kateřina (referee)
Phytohormones are signalling molecules directing physiological and developmental processes in plants. One of them, auxin, is involved in the diverse regulation of plant processes, e.g. embryogenesis, organogenesis, vascular tissue formation and tropisms. Auxin transport is polar. Auxin isdistributed via the phloem, utilizing specialized membrane transport proteins; small amount diffuse also through the membrane. Aux1/Lax transporters mediate auxin entry into the cell, auxin efflux is mediate mostly by PIN transporters, which are the crucial factors in determining the directionality of auxin flow. Asymmetric localization of membrane PIN proteins depends on vesicle transport from Golgi to the plasma membrane. Vesicles are transported along actin filaments which are dynamically rebuilted by regulators. They are maintaining asymmetric cellular localization of the auxin transport proteins. PIN proteins are cycling between endosomes and plasma membrane. Cycling is regulated by ARF-GEF proteins and serin/threonin kinase (PID, PINOID). Newly synthesized PIN proteins are equally distributed in the plasma membrane, afterwards they are asymmetrically redistributed. Regulation of actin filaments formation and remodelling is the crucial factor for transport of vesicles with PIN proteins. Many proteins which regulate...
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The oxidative DNA damage and its relationship to the cytotoxic effect.
Blahová, Hana ; Hochmann, Jiří (advisor) ; Polívková, Zdeňka (referee)
This work has been focused on the study of oxidative DNA damage induced with hydrogen peroxide and on the relationship of this damage to cytotoxic effect . The repair of the oxidative DNA damage and the cell survival was followed both in normal Chinese hamster cells and their mutant derivative UV-20. The modified single cell gel electrophoresis (the comet assay,) was used to estimate the DNA damage. The cytotoxiciy was measured using the inhibition of colony forming capacity of cells. Both normal AA8 and mutant UV-20 cells repair the oxidative DNA damage with approximately the same velocity, and they show also the same sensitivity towards the hydrogen peroxide. These results indicate, that the defect in the nucleotide excision DNA repair in UV-20 cells does not play any important role in the response of these cells to the oxidative DNA damage, and therefore this mechanism is not involved in the removal of this damage. This may indicate, that the main mechanism of the repair of oxidative DNA damage is the base excision repair. Keywords: Oxidative DNA damage, hydrogen peroxide, comet assay, excision repair.
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Differentiation of yeast colonies and development of new approaches to monitor oxygen and nutrient availability
Vopálenská, Irena ; Janderová, Blanka (advisor) ; Demnerová, Kateřina (referee) ; Pichová, Iva (referee)
Yeast Saccharomyces cerevisiae as an unicellular organism is one of the best-studied experimental organisms. It is an important model organism for the study of intracellular processes of eukaryotic cells. Yeasts are also social organisms with cell-to-cell communication able to form organized multicellular structures (colonies and biofilms). Yeast and other microorganisms in nature prefer to form colonies on solid substrates rather than to grow as "planktonic" single cells (Palková, 2004; Wimpenny, 2009). The yeast S. cerevisiae typically forms colonies, biofilms were described only rarely. Yeast colonies exhibit an organized morphological pattern characteristic of each particular yeast strain (Kocková-Kratochvílová, 1982). This work is focusing on morphology and differentiation of the S. cerevisiae colonies of common laboratory strains forming less structured colonies, and strains of the Σ1278b genetic background forming highly structured "fluffy" colonies. It shows that polarized budding pattern and especially cell ability to form aggregates enable development of structured morphology. During development of "fluffy" colonies two differently regulated events of dimorphic switch from yeast form to filamentous growth occur. One of these events is dependent on the surface glycoprotein, Flo11p flocculin. This...
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