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Assessment of fracture risk for a langlauf ski made as a glass fibre reinforced sandwich
Láštic, Daniel ; Majer, Zdeněk (referee) ; Burša, Jiří (advisor)
The first part of bachelor’s thesis is devoted to basic theoretical knowledge about usage of sandwich theory of beams, which are made of different materials in the core and faces. This part includes brief description of composites (common car- rying component of sandwich structures) with emphasis put on the fibre compo- sites and laminates. A special characteristic of composites – orthotropy is men- tioned. The second part is focused on description of obtaining of elastic constants of materials used in the real cross-country ski by experiment, on stress calculation and fracture risk assessment in cross-country ski made as sandwich structure for the most adverse operational state. The solution is executed with the help of an- alytical formulas of mechanics of materials derived in this part. The problem is also solved using finite element method (FEM) employing ANSYS software.
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Mechanisms of invasiveness and transcription regulation in cancer cells
Tolde, Ondřej ; Folk, Petr (advisor) ; Kovář, Jan (referee) ; Brdička, Tomáš (referee)
The mechanisms of invazivity and regulation of transcription of cancer cells Cancer originates in cells that overcome the control mechanisms of the organism. Cancer cells can be eventually released from the site of origin and spread through tissues. Cancer cells can acquire certain mechanisms that enable them to more effectively invade surrounding tissue or layers of other cells. The research on the migration of cancer cells is important for the understanding of the origin and spreading of metastases and consequently for anticancer therapy. In my Ph.D. work, I participated in the research of the properties of invasive metastatic cells. We compared non-invasive rat sarcoma cell line with a higly metastatic cell line derived from it. We showed that cells of the invasive cell line use amoeboid mode of migration, have upregulated Rho/ROCK signaling, and have accumulated actin and myosin at the leading edge. It is at the leading edge where the cells generate their traction forces. Cells of non-invasive cell line use mesenchymal mode of migration and generate forces mainly at their retracting end. We also compared two breast cancer cell lines derived from a single carcinoma. We showed that the more invasive cell line, derived from its parental line by neoplastic transformation, displayed elevated cytoskeletal...
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Panels of steroid receptor reporter cell lines for compound profiling and development of selective ligands for estrogen receptor alpha and beta
Sedlák, David ; Bartůněk, Petr (advisor) ; Anzenbacher, Pavel (referee) ; Kasal, Alexander (referee)
of the Ph.D. thesis Steroid hormone receptors represent a major target in the drug discovery. As ligand inducible transcription factors, their activity can be modulated by small lipophilic molecules. The first part of this work describes a preparation of two panels of potent, selective and robust luciferase reporter cell lines on the unified cellular background in U2OS osteosarcoma cell line. This system consists of two panels of stable luciferase reporter cell lines for estrogen receptor α (ERα), estrogen receptor β (ERβ), androgen receptor (AR), glucocorticoid receptor (GR), mineralocorticoid receptor (MR) and progesterone receptor (PR). The first panel of reporter cell lines relies on the expression of the chimeric steroid receptors created by the replacement of the N-terminal part of the steroid receptor molecule by Gal4 DNA binding domain (Gal4 DBD) binding to 9 copies of Gal4 upstream activation sequences (Gal4 UAS) in the promoter of the pGL4 luciferase reporter vector. In the second panel of reporter cell lines the activation of either synthetic promoter containing multiple hormone response elements or viral promoter derived from MMTV LTR is mediated by full- length exogenously expressed steroid receptors. We have extensively validated both panels using 28 well established ligands, carefully...
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Modulation of metabolic activation of ellipticine by components of the mixed function monooxygenase system
Mrázová, Barbora ; Stiborová, Marie (advisor) ; Tichá, Marie (referee) ; Souček, Pavel (referee)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF SCIENCE, DEPARTMENT OF BIOCHEMISTRY Modulation of metabolic activation of ellipticine by components of the mixed function monooxygenase system Summary of PhD Thesis RNDr. Barbora Mrázová Supervisor: Prof. RNDr. Marie Stiborová, DrSc. Praha 2010 RNDr. Barbora Mrázová Introduction 1 IINNTTRROODDUUCCTTIIOONN Ellipticine (5,11-dimethyl-6H-pyrido [4,3-b] carbazole, figure 1) and its more soluble derivates are alkaloids isolated from Apocyanaceae plants, which exhibit significant antitumor activities[15, 21, 24, 31] . Ellipticine was first isolated in 1959 from the leaves of the evergreen tree Ochrosia elliptica Labil[6] . Nevertheless, its pharmacological efficiencies (and efficiencies of some of its derivates) was found in 1967, when they were prepared by chemical syntheses[7] . Ellipticine and its more soluble derivates, 9-methoxy- ellipticine and 2-methyl-9-hydroxyellipticine in the form of acetate, have been utilized pharmacologically since 1970s. They are highly efficient against osteolytic breast cancer with metastases, acute myeloblastic leukemia, kidney sarcoma and thyroid carcinoma[1, 17, 18, 19, 23] . Ellipticines exhibit also significant anti-HIV activity because of their ability to inhibit retroviral integrase. This is the reason, why ellipticine is also...
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Study on metabolism of 3-aminobenzanthrone and induction of biotransformation enzymes
Mizerovská, Jana ; Stiborová, Marie (advisor) ; Mareš, Jaroslav (referee) ; Hýsková, Veronika (referee)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF SCIENCE DEPARTMENT OF BIOCHEMISTRY Study on metabolism of 3-aminobenzanthrone and induction of biotransformation enzymes Summary of PhD Thesis RNDr. Jana Mizerovská Supervisor: Prof. RNDr. Marie Stiborová, DrSc. Prague 2010 RNDr. Jana Mizerovská Introduction 1 INTRODUCTION 3-Nitrobenzanthron, precursor of 3-ABA The nitroaromatic 3-nitrobenzanthrone (3-nitro-7H-benz de anthracen-7-one, 3-NBA) occurs in diesel exhaust and in airborne particulate matter(8, 9, 14) . 3-NBA is most likely formed during the atmospheric reaction of benzanthrone with nitrogen oxides, especially in the presence of ozone, or during imperfect burning of diesel. 3-NBA exhibits extremely high mutagenic activity(9, 14) and is also a genotoxic carcinogen causing lung tumors in rats(14) . 3-NBA is also evaluated to be a potential carcinogen for humans(14, 1, 9, 19) . The genotoxicity of 3-NBA was documented by the detection of specific 3-NBA-derived DNA adducts in vitro, in human cell lines and also in vivo in rats and mice(12, 13, 15, 2) . The predominant DNA adducts formed by 3-NBA after its metabolic activation by reduction of the nitro group are 2-(2'-deoxyguanosin-N2 -yl)-3- aminobenzanthrone and N-(2'-deoxyguanosin-8-yl)-3-aminobenzanthrone(9, 14) and these are most probably responsible for the...
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Variability and silencing of transgene expression in potato plants and in tobacco cell line BY-2
Nocarová, Eva ; Fischer, Lukáš (advisor) ; Moravec, Tomáš (referee) ; Kovařík, Aleš (referee)
Conclusions In suspension cultures of tobacco BY-2 cell line derived from calli after transformation about 90 % of lines contained cells with various GFP fluorescence level after transformation. Newly introduced cloning method allowed obtaining nearly 50 % of clones with homogeneous GFP expression from primarily heterogeneous BY-2 lines. Heterogeneity of GFP expression in transgenic BY-2 lines had two causes - genetic (primary lines contained cells with different T-DNA insertions) and epigenetic one. Epigenetic heterogeneity of BY-2 lines was connected with transgene silencing, formation of stable epigenetic states early after transformation, and "permanent heterogeneity" with fluctuating levels in GFP expression. Reduction or silencing of transgene expression in potato was predominantly observed in lines with higher number of T-DNA insertions and with higher initial GFP expression. Silencing in potato always gradually affected both introduced genes. Silencing of GFP expression preceded (in months) loss of resistance to kanamycin (silencing of NPTII gene) in all monitored cases that indicates interconnections between silencing of both transgenes. The same sequence of silencing of both transgenes in potato was also observed in silenced lines after reactivation of transgene expression by 5-azacytidine, which...
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Systems for Generation of Pulse Magnetic Vector Potential
Hanák, Pavel ; Makáň,, Florian (referee) ; Bartušek, Karel (referee) ; Vrba, Kamil (advisor)
The doctoral thesis is focused on research, design, implementation and testing of systems for the application of magnetic vector potential to biological materials. The main objective was to analyze and design systems which could generate magnetic vector potential without the presence of other unwanted fields or at least amplify its intensity. Moreover, the systems designed had to eliminate other foreign effects on the biological samples, especially the influence of waste heat from the coils. Toroidal coils were employed to generate the vector potential, because they confine the unwanted magnetic induction inside their core thanks to their shape. The thesis employed coils with two different outer diameters, specifically 102 and 600 mm. To excite the coils, four current pulse generators capable of delivering currents of up to 100 A were constructed. The systems’ generated fields were comprehensively analyzed with the help of finite-element simulations in ANSYS. To simplify the design phase, analytical equations for the calculation of vector potential intensity at an arbitrary point around the toroidal coils were also derived. A method employing electromagnetic shielding made of two different materials was developed to suppress the unwanted fields. To eliminate the influence of heat, the 102 mm system employed air cooling and the 600 mm system employed a closed water loop to equalize the temperatures of biological samples. The biological effects of both systems were tested on genetically modified bio-luminescent bacteria Escherichia coli K12 luxABCDEamp. The thesis was created in connection with the research project of The Ministry of Education, Youth and Sports of the Czech Republic named “Research into the effect of a combination of substances for targeted therapy and inhibitory action of the field pulse vector magnetic potential on oncogenous diseases”, No. 2B08063.
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Singular Initial Value Problem for Ordinary Differential and Integrodifferential Equations
Archalousová, Olga ; Beránek, Jaroslav (referee) ; Růžičková,, Miroslava (referee) ; Šmarda, Zdeněk (advisor)
The thesis deals with qualitative properties of solutions of singular initial value problems for ordinary differential and integrodifferential equations which occur in the theory of linear and nonlinear electrical circuits and the theory of therminionic currents. The research is concentrated especially on questions of existence and uniqueness of solutions, asymptotic estimates of solutions and modications of Adomian decomposition method for singular initial problems. Solution algoritms are derived for scalar differential equations of Lane-Emden type using Taylor series and modication of the Adomian decomposition method. For certain classes of nonlinear of integrodifferential equations asymptotic expansions of solutions are constructed in a neighbourhood of a singular point. By means of the combination of Wazewski's topological method and Schauder xed-point theorem there are proved asymptotic estimates of solutions in a region which is homeomorphic to a cone having vertex coinciding with the initial point. Using Banach xed-point theorem the uniqueness of a solution of the singular initial value problem is proved for systems of integrodifferential equations of Volterra and Fredholm type including implicit systems. Moreover, conditions of continuous dependence of a solution on a parameter are determined. Obtained results are presented in illustrative examples.
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Nonnegative time series
Ročková, Veronika ; Anděl, Jiří (advisor) ; Štěpán, Josef (referee)
Models for non-negative time series nd their usefulness in many diverse areas of applications (hydrology, medicine, nance). The non-negative nature of the observations has been utilized for deriving estimators with superior asymptotic properties. For the purposes of estimation, it is necessary to recognize the situations when the estimated model indeed de nes a non-negative time series. Such non-negativity conditions can then be used as a basis for constrained optimization. The main thrust of this work is to review the non-negativity conditions currently available for ARMA models and, more importantly, to generalize the existing results for some models for which the explicit result was missing. We center our discussion mainly on univariate models. However, we note that the pursued ideas are directly applicable also for multivariate time series. This observation enables determination of some readily obtainable conditions for lower order vector valued Autoregressive Moving Average models.
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Production of Selected Yeast Metabolites Applicable to Food Supplements
Němcová, Andrea ; Čertík, Milan (referee) ; Vávrová, Milada (referee) ; Márová, Ivana (advisor)
Carotenoids are naturally occurring pigments of plants also produced in many bacteria, and fungi. They represent one of the widest group of natural antioxidants with significant biological effects and numerous of industrial applications. There is an increased interest in carotenoids as natural antioxidants for their ability to reduce chronic diseases, various pathological stages and aging. The area of their application concerns mainly food industry; however, they are used in chemical, pharmaceutical, and cosmetics industry as well. One possibility is study of potential of red yeasts that are able to convert various substrates into carotenoid pigments. In presented thesis carotenogenic yeast belonging to the genus Rhodotorula, Sporobolomyces and Cystofilobasidium were tested for ability to use of selected waste substrates and also random mutagenesis in order to increase the production of biomass and specific metabolites – carotenoids and other lipid-soluble substances. As alternative nutrient sources derived from waste substrates from agricultural and food production (rapeseed substrate, rice, wheat, apple fiber, pasta and lignocellusic materials) were tested. To selected production media extracellular hydrolytic enzymes or commercial enzymes degrading polysaccharide were added. All tested red yeast strains were able to utilize these substrates as the only carbon source and simultaneous produce carotenoid enriched biomass. In this work, characterization of carotenogenic yeast using molecular techniques was studied. For this usage, interspecific variables of strongly conserved sequences of genomic DNA, especially rDNA D1/D2 large ribosomal subunit and ITS1 and 5,8-ITS2 rDNA regions were amplified. These sequences were subjected analysed by DGGE method to compare differences of carotenogenic yeasts. Isolation procedure of the intact DNA were optimized for caryotypic yeast characterization by pulsed field gel electrophoresis (PFGE). The karyotype of tested yeasts contain visible differences between yeast species and genera.
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