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Quantitative analysis of tyrosine kinase inhibitors employing liquid chromatography with mass spectrometry detection
Maier, Jan ; Pávek, Petr (advisor) ; Lochman, Lukáš (referee)
The submitted thesis is devoted to the quantitative analysis of tyrosine kinase inhibitors, specifically imatinib and nilotinib, by liquid chromatography-mass spectrometry method. The main purpose of developing this new method of analysis at the Department of Clinical Biochemistry and Diagnostics at the University Hospital in Hradec Králové was measuring and monitoring serum or plasma concentration levels of these drugs in patients with chronic myeloid leukemia, less often in patients with gastrointestinal stromal tumour. The main task during the elaboration of the thesis was to fully optimize and validate the method. Previously, this method for the analysis of tyrosine kinase inhibitors was routinely performed here by high-performance liquid chromatography with spectrophotometric (UV) detection. As part of the modernization of laboratory technology, they started to use high-performance liquid chromatography with mass spectrometry at the workplace. The analytes with their internal standards were obtained by a liquid-liquid extraction process. Then, samples were separated on a C18 reverse phase column using isocratic elution. Subsequently, both analytes were detected by a triple quadrupole tandem mass spectrometer with ESI ion source in a positive mode. As a part of the method validation was to...
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The effect of resveratrol and gambogic acid on the DNA damage caused by daunorubicin in neonatal rat cardiomyocytes.
Mašín, Martin ; Jirkovská, Anna (advisor) ; Pávek, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Martin Mašín Supervisor: PharmDr. Anna Jirkovská, Ph.D. Title of diploma thesis: The effect of resveratrol and gambogic acid on the DNA damage caused by daunorubicin in neonatal rat cardiomyocytes. DNA Topoisomerases comprise a family of enzymes that are able to alter DNA topology by transient single- or double-strand breaks (DSB) during fundamental processes such as replication and transcription. Inhibition of topoisomerase II (TOP II) is the main mechanism of action of some antitumour drugs, such as anthracyclines (ANT; e.g., daunorubicin). They stabilize the DNA-TOP II complex, leading to the formation of DSBs and later to apoptosis. Other inhibitors, that interact with the enzyme without the DSB formation, can modulate the effect of ANT. In this thesis, we studied the DNA damage caused by daunorubicin (DAU) and its main metabolite daunorubicinol (DAUnol) and the effect of two naturally-derived compounds and TOP II catalytic inhibitors resveratrol (RES) and gambogic acid (GA) in neonatal rat cardiomyocytes. The DNA damage was determined as the extent of histone H2AX phosphorylation (γ-H2AX) and by Comet Assay. It can be concluded that both DAU and DAUnol (1,2 μM) exhibit DNA damage that is...
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Endocrine disruptors as ligands of nuclear receptors.
Tóthová, Veronika ; Pávek, Petr (advisor) ; Jirkovský, Eduard (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Veronika Tóthová Supervisor: prof. PharmDr. Petr Pávek, Ph.D. Title of diploma thesis: Endocrine disruptors as ligands of nuclear receptors Endocrine disruptors are synthetic substances used in many areas of industry or agriculture that negatively affect and interfere with the functions of the endocrine system. Their negative effects have been mentioned since the beginning of the 20th century, but only recently have more attention been paid to them due to their adverse effects on the human organism and the environment. In the thesis, we summarized the mechanisms of action of the most well-known endocrine disruptors on selected nuclear receptors. Specifically, it was bisphenol A and phthalate-type compounds. From nuclear receptors, we focused on PPAR (Peroxisome Proliferator-Activated Receptors), Pregnane X receptor (PXR) and Aryl androstane receptor (AHR). From the information obtained, it follows that we are in constant contact with these substances, and therefore we should devote more attention to studying their effects, because not all mechanisms of action and effects of these compounds are completely known. In this way, we could increase the safety of using these substances,...
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The effect of resveratrol and gambogic acid on the DNA damage caused by daunorubicin in neonatal rat cardiomyocytes.
Mašín, Martin ; Jirkovská, Anna (advisor) ; Pávek, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Martin Mašín Supervisor: PharmDr. Anna Jirkovská, Ph.D. Title of diploma thesis: The effect of resveratrol and gambogic acid on the DNA damage caused by daunorubicin in neonatal rat cardiomyocytes. DNA Topoisomerases comprise a family of enzymes that are able to alter DNA topology by transient single- or double-strand breaks (DSB) during fundamental processes such as replication and transcription. Inhibition of topoisomerase II (TOP II) is the main mechanism of action of some antitumour drugs, such as anthracyclines (ANT; e.g., daunorubicin). They stabilize the DNA-TOP II complex, leading to the formation of DSBs and later to apoptosis. Other inhibitors, that interact with the enzyme without the DSB formation, can modulate the effect of ANT. In this thesis, we studied the DNA damage caused by daunorubicin (DAU) and its main metabolite daunorubicinol (DAUnol) and the effect of two naturally-derived compounds and TOP II catalytic inhibitors resveratrol (RES) and gambogic acid (GA) in neonatal rat cardiomyocytes. The DNA damage was determined as the extent of histone H2AX phosphorylation (γ-H2AX) and by Comet Assay. It can be concluded that both DAU and DAUnol (1,2 μM) exhibit DNA damage that is...
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Screening of selected alkaloids of Fumariaceae and Amaryllidaceae families on Farnesoid X receptor and the G protein-coupled bile acid receptor 1
Hutníková, Miriama ; Pávek, Petr (advisor) ; Chlebek, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Miriama Hutníková Supervisor: Prof. PharmDr. Petr Pávek, PhD. Title of diploma thesis: Screening of selected alkaloids of Fumariaceae and Amaryllidaceae families on the farnesoid X receptor and the G protein coupled receptor 1 Farnesoid X receptor (FXR) and bile acid receptor associated with G protein 1 (TGR5) significantly affect metabolic processes in the human body. The role of FXR in neuronal apoptosis in Alzheimer's disease (AD) has also been discovered. The possible structural similarity of the small lipophilic molecules binding to these receptors and the alkaloids found in the plants Corydalis cava and Narcissus pseudonarcissus, as well as the richoften use of these plants in traditional medicine, represent a potential therapeutic intervention for these molecules. In our screening methods, we performed tests using a luciferase gene reporter assay to determine the ability of the alkaloids to interact with FXR and TGR5 in the HepG2 cell line. Many derivatives have shown a strong ability to antagonize FXR and TGR5 activated by obethicholic (OCA) or litocholic (LCA) acids in this assay. Some of the compounds also demonstrated the ability to potentiate the effects of OCA or LCA. Cytotoxicity...
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The effect of flubendazole on temozolomide treatment in glioblastoma cells
Dvořáková, Kateřina ; Skálová, Lenka (advisor) ; Pávek, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Kateřina Dvořáková Supervisor: prof. RNDr. Lenka Skálová, Ph.D. Title of diploma thesis: The effect of flubendazole on temozolomide treatment in glioblastoma cells Glioblastoma multiforme (GBM) is one of the most common and aggressive brain tumors in adults. Despite significant advances in treatment, GBM remains to have very poor prognosis and median survival of only 12 to 15 months after diagnosis. Standard treatment consists of maximal possible surgical resection followed by chemo-radiotherapy with antitumor drug temozolomide (TMZ), which use is problematic due to fast developing chemoresistance. The aim of this study was to examine the effect of potential anticancer drug, anthelmintic flubendazole (FLU) and effect of FLU in combination with TMZ on GBM cells. For this purpose, two GBM cell lines were used - A172 and T98G. In general FLU reduced cell proliferation more, especially in T98G cells. Moreover, the use of different combinations of TMZ + FLU showed even higher inhibitory effect on the viability of GBM cell lines. The combination of TMZ + FLU reduced the protein level of -tubulin and III-tubulin, simoultaneously interesting changes in STAT3 and EGFR expression, as well as lower...
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Development of novel Constitutive androstane receptor (CAR) ligands
Dušek, Jan ; Pávek, Petr (advisor) ; Hudeček, Jiří (referee) ; Chládek, Jaroslav (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate Mgr. Jan Dušek Supervisor Prof. PharmDr. Petr Pávek, Ph.D. Title of Doctoral Thesis Development of novel Constitutive androstane receptor (CAR) ligands Constitutive androstane receptor is nowadays known as the established nuclear receptor that regulates the expression of several key cytochrome P450 enzymes, predominantly CYP3A4 and CYP2B6. Recently it has been shown that CAR has also essential role in the regulation of endogenous metabolism of glucose, lipids, cholesterole or bile acids. Simultaneously, this receptor is considered to have proliferative effect on human hepatocytes and protective effects against toxic and dietary damage of liver parenchyme. Given the possible therapeutic utilization of CAR, its therapeutic options are being intensively studied. Unfortunately, currently known ligands of human or mouse CAR are either poorly selective or indirect. The aim of my doctoral thesis was to find new ligands of mouse and human CAR, that would enable more detailed study of the receptor.
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Selected aspects of methotrexate treatment in patients with rheumatoid arthritis
Hloch, Karel ; Pávek, Petr (advisor) ; Souček, Miroslav (referee) ; Tomčík, Michal (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Training Workplace Department of Social and Clinical Pharmacy Doctoral Degree Program Clinical and Social Pharmacy Candidate MSc. Karel Hloch Supervisor prof. PharmD. Petr Pávek, Ph.D. Advisor assoc. prof. MUDr. Tomáš Soukup, Ph.D.; PharmD. Martin Doseděl, Ph.D. Title of Doctoral Thesis: Selected aspects of methotrexate treatment in patients with rheumatoid arthritis Introduction and objectives Rheumatoid arthritis (RA) is an autoimmune disease typically connected with chronic inflammation of the joints, causing their swelling and pain. The prevalence of RA is about 1% in the general population. A crucial role in higher morbidity and mortality in RA patients has been associated with increased inflammatory activity. Methotrexate (MTX), a drug with immunosuppressive activity, is the most frequent drug of choice used in RA therapy. It seems that main anti-inflammatory effect is mediated via release of purine nucleoside adenosine. The status of patients with inflammatory diseases is influenced by activation of A2a and A3 adenosine receptors. High caffeine (adenosine receptor antagonist) consumption may therefore lead to alteration of MTX treatment efficacy. 1) The aim of first study was to determine whether RA patients who had discontinued...
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Screening of selected alkaloids of Fumariaceae and Amaryllidaceae families on Farnesoid X receptor and the G protein-coupled bile acid receptor 1
Hutníková, Miriama ; Pávek, Petr (advisor) ; Chlebek, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Miriama Hutníková Supervisor: Prof. PharmDr. Petr Pávek, PhD. Title of diploma thesis: Screening of selected alkaloids of Fumariaceae and Amaryllidaceae families on the farnesoid X receptor and the G protein coupled receptor 1 Farnesoid X receptor (FXR) and bile acid receptor associated with G protein 1 (TGR5) significantly affect metabolic processes in the human body. The role of FXR in neuronal apoptosis in Alzheimer's disease (AD) has also been discovered. The possible structural similarity of the small lipophilic molecules binding to these receptors and the alkaloids found in the plants Corydalis cava and Narcissus pseudonarcissus, as well as the richoften use of these plants in traditional medicine, represent a potential therapeutic intervention for these molecules. In our screening methods, we performed tests using a luciferase gene reporter assay to determine the ability of the alkaloids to interact with FXR and TGR5 in the HepG2 cell line. Many derivatives have shown a strong ability to antagonize FXR and TGR5 activated by obethicholic (OCA) or litocholic (LCA) acids in this assay. Some of the compounds also demonstrated the ability to potentiate the effects of OCA or LCA. Cytotoxicity...
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Bioinformatic aspects of nuclear receptors in pharmacotherapy
Škoda, Josef ; Pávek, Petr (advisor) ; Kollár, Peter (referee) ; Matoušková, Petra (referee)
IN ENGLISH LANGUAGE Candidate: Mgr. Josef Škoda Supervisor: Prof. PharmDr. Petr Pávek, PhD. Title of the doctoral thesis: Bioinformatical aspects of nuclear receptors in pharmacotherapy The liver plays a central role in energy homeostasis via processing post-prandial excess energy into storage molecules and reusing stored energy via gluconeogenesis during the fasting period. This tight energy balance is maintained by a myriad of regulating processes. Dysfunction of metabolic control is a key event of severe diseases in today's population, starting with obesity, insulin resistance, and metabolic syndrome, proceeding to end-stage complications in type 2 diabetes, whole organ malfunctions, or even tumor diseases. Master players in metabolic regulation are nuclear receptors (NR) activated by endogenous stimuli or scavenging for nutritional or toxicological signals. NRs regulate gene transcription activation and therefore maintain liver metabolic plasticity. In this thesis, modern molecular biology approaches were used to study ligands of NRs and the effects of their treatment. After the typical activation of a NR, hundreds of genes are regulated, which is beyond the ability to study with conventional biology methods. For this purpose, omics methods are an ideal solution. They are characterized by...
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