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One-tier organisational structure of Czech joint-stock companies and British public limited companies
Václavíková, Radka ; Černá, Stanislava (advisor) ; Tomášek, Petr (referee)
1 One-tier organisational structure of Czech joint-stock companies and British public limited companies Abstract This thesis deals with selected issues of one-tier board structure of a joint-stock company in the Czech and British legislation. The emphasis is placed on the position and regulation of the Board of directors, its members, shareholders, and their mutual relationship. Not only has the present legal regulation been monitored, but also its historical roots, which significantly influenced the evolution of the institute and its present form. The first chapter deals with corporate governance. It includes all aspects and theories, which as a whole have completed the position of a shareholder as well as a joint-stock company itself. Moreover, diffuse and concentrated ownership is explained, as well as separation of ownership of the company from its management, and the related "principal"-"agent" problem. Also, the basic characteristics of Anglo-Saxon and continental approach to the law have been reflected. The second chapter describes and clarifies the essence and the form of one-tier board structure as it is regulated in the UK. A remarkable element of British company law is the extent to which the company's internal affairs are left to its shareholders through the company's articles of association....
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The study of the factors affecting colorectal cancer chemotherapy
Dolníková, Alexandra ; Opattová, Alena (advisor) ; Václavíková, Radka (referee)
Application of cytotoxic chemotherapy still remains the essential treatment strategy in advanced colorectal cancer. The intrinsic and acquired drug resistance represents one of the reasons that may even lead to failure of cancer therapy. The DNA damage response pathways have been shown to play an important role in the development of chemoresistance. There is sufficient evidence showing the high-frequency deregulated expression of many DNA repair genes across multiple cancer types. An example of such gene in colorectal cancer is MRE11, which encodes protein known as a sensor of DNA double-strand breaks. In year 2016, there was a substantial study published by our group at The Department of Molecular Biology of Cancer (IEM CAS, Prague), the study analysed the association of polymorphisms in predicted microRNA target sites of double-strand breaks (DSBs) repair genes, including MRE11, and clinical outcome and efficacy of chemotherapy in colorectal cancer. Our hypothesis, based on the mentioned study, is that specifically and exactly defined microRNAs with ability to regulate certain DNA repair proteins may not only affect the survival of colorectal cancer cells, but also the sensitivity to chemotherapy. In practical part of the submitted thesis we have identified miR-140 as a potential regulator of...
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The effect of tyrosinkinase inhibitors vandetanib and lenvatinib and cytotoxic alkaloid ellipticine on biotransformation enzymes
Baráčková, Petra ; Dračínská, Helena (advisor) ; Václavíková, Radka (referee)
In recent years, tyrosine kinase inhibitors have been widely used for the treatment of certain tumors as so-called targeted therapy. Many studies are concerned with their metabolism and the role of enzymes in the biotransformation process, but very little is known about the impact of tyrosine kinase inhibitors on the expression and activity of biotransformation enzymes. Nevertheless modification of the expression and activity of enzymes may cause adverse interactions of co-administered drugs and their negative impact on the human body. This diploma thesis studies the effect of tyrosine kinase inhibitors vandetanib and lenvatinib and cytotoxic alkaloid ellipticine on biotransformation enzymes in a rat model organism in vivo. The aim was to characterize the effect of the investigated compounds on gene expression, protein expression and activity of cytochromes P450 (CYP) 1A1, 1A2 and 1B1 and flavin-containing monooxygenases FMO1 and FMO3 in renal and hepatic microsomes. Microsomes and RNA were isolated from kidneys of control rats and the pretreated rats. Western blot and immunodetection was used to compare the protein expression levels of studied enzymes in kidney and liver. By reverse transcription, cDNA was prepared from isolated RNA and used as a template for quantitative PCR to compare the...
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Metabolism, transport and anticancer effect of classical and novel taxanes
Václavíková, Radka ; Gut, Ivan (advisor) ; Perlík, František (referee) ; Anzenbacherová, Eva (referee)
L I I I I I I I I t CONCLUSIONS The dissertation thesis contributes to detail knowledge of the metabolism, transport and anticancer effects of classical taxanes (paclitaxel and docetaxel) as well as their novel synthetic analogs (SB-T-1103, SB-1'-1214 and SB-T-1216). The r]lost rmportanl reslrlts concerning studies on these anticancet drugs are srultnarized as iollorvs: o Detail metabolisrrr oť paclitaxel and docetaxel rvas estimated in human. rat. pig arrd minipig liver microsomes. The metabolism of docetaxel rvas the same i:r all four tested species. Drug rvas metabolized mainly to hydroxydocetaxel and two minor h1'droxyoxazol.idinones A and B. Despite various simiiarities between human and pig netabolism of paclitaxel, the profile oť paclitaxel metabolites in the studied species r'u.as different and main hunan metabolite óo.oHP renrains uniquelv human one' The other new metabolites of paclitaxel w.ere revealed. speciíicall1 di-oHP in ra1s and a new. hydroxypaclitaxel in rats. pigs and minipigs. q,here thrs metabolite is the main metabolic pathway oť paciitaxel. The major enzymes responsible for oxidative metaboiism of paclitaxei are CYP2CB and CYP3A4 in humans and CYP3Ai/2 in rats. Docelaxel is oxidatively metabolized by GYP3A famil"v in humans as rvell as in rats. The oxidation metabolism of classical...
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Determination of methylation in the promotor regions of genes, that control metabolism of 5-FU
Bendová, Petra ; Vodička, Pavel (advisor) ; Václavíková, Radka (referee)
Several malignant diseases, such as colorectal, pancreatic, breast or ovarial cancers, are primarily treated with cytostatics 5-fluorouracil (5-FU). 5-FU undergoes biotransformation in human body and arising metabolites induce the damage and subsequent apoptosis in the target cells. The main aim of this diploma Thesis was the determination of methylation in promoter regions of 14 candidate genes participating on 5-FU biotransformation: TK1, PPAT, RRM1, RRM2, UCK2, UCK1, UMPS, TYMP, UPP1, UPP 2 SLC29A1, UPB1, DPYS and DPYD. We hypothesize that the methylation in promoter regions regulates mRNA transcription of the above candidate genes. We have conducted appropriate analyses in 128 colorectal cancer patients, for whom both tumor and nonmalignant adjacent tissues were available. Sample processing and analysis involved DNA isolation, bisulfite conversion of unmethylated cytosines to corresponding uracils, methylation-specific analysis of melting curves with high resolution for theproper methylation analysis and gel electrophoresis to separate PCR products. For the majority of the studied genes (TK1, PPAT, RRM1, RRM2, UCK2, UCK1, UMPS, TYMP, UPP1, SLC29A1 and DPYD) we did not detect any aberrant methylation in promoter regions. In genes DPYS, UPB1 and UPP2 we recorded various degree of promoter...
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Effects of chemopreventive compounds on cytochrome P450s
Křížková, Jitka ; Hodek, Petr (advisor) ; Helia, Otto (referee) ; Václavíková, Radka (referee)
CHARLES UNIVERSITY IN PRAGUE Faculty of Science Department of Biochemistry Effects of chemopreventive compounds on cytochrome P450s Summary of Ph.D. Thesis RNDr. Jitka Křížková Supervisor: prof. RNDr. Petr Hodek, CSc. Prague 2010 Introduction 1 Introduction According to the World Health Organization statistics, cancer is one of the leading causes of death in the human population worldwide for more than 50 years. Moreover, colorectal and gastrointestinal tract cancers are one of the main types of cancer leading to overall cancer mortality. Prevention consisting in a healthy lifestyle and a natural diet is suggested to be one of the main approaches to reduce cancer risk. In recent years, the consumption and use of dietary supplements containing concentrated chemopreventive phytochemicals increased dramatically. Flavonoids, as the most popular representatives of chemopreventive compounds, present in foods (fruits, vegetables, herbs, beverages) and dietary supplements have the potential to modulate the activity of xenobiotic-metabolizing enzymes [Hodek et al., 2002]. Among proteins interacting with flavonoids, cytochrome P450s (CYPs), monooxygenases metabolizing xenobiotics (e.g. drugs, carcinogens), play the most prominent role. The two members of CYP1A subfamily, CYP1A1 and CYP1A2, are involved in the...
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