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Frequency of selected genetic polymorphisms of cytochrome P450 in the Czech population and the influence of CYP2C9 genotype on the hypolipidemic effect of fluvastatin
Buzková, Helena ; Perlík, František (advisor) ; Bultas, Jan (referee) ; Mičuda, Stanislav (referee)
55 Abstract Frequency of selected genetic polymorphisms of cytochrome P450 in the Czech population and the influence of CYP2C9 genotype on the hypolipidemic effect of fluvastatin Introduction: One of the main factors of genetically determined variability in response of humans to administered drugs are differences in catalytic activity of metabolizing enzymes, which are caused mainly by genetic polymorphisms in cytochrom P450 family enzymes. This thesis consists of two parts and it is presented as a commentary to the original papers. The first aim was to investigate the frequency of functionally important variant alleles of three main isoenzymes of cytochrome P450 gene: CYP2D6, CYP2C9, CYP2C19, throughout the Czech population, predict the prevalence of poor metabolizer phenotypes, and then to compare the results to the data from other populations. Secondly, we analysed the correlation between the CYP2C9 genotype and cholesterol-lowering effect of fluvastatin in human hypercholesterolemic patients. Methods: Genotypes were determined by PCR-RFLP. The presence of alleles CYP2D6*1, *6, *5, *4, *3, and gene duplication was analysed in 233 healthy volunteers, CYP2C9*1, *2 and*3 in 254 subjects and CYP2C19*1, *2 and *2 in 218 subjects. Eighty seven patients on fluvastatin therapy, and 48 patients on monotherapy...
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Circadian rhythm of parathyroid hormone and bone remodeling: implication for the osteoporosis treatment with teriparatide (parathormone [1-34])
Rašková, Mária ; Zikán, Vít (advisor) ; Žofková, Ivana (referee) ; Perlík, František (referee)
Circadian rhythm of parathyroid hormone (PTH) is well documented, but its physiological role is not fully understood. In healthy individuals, biochemical markers of bone remodeling follow a similar circadian rhythm to PTH with a nocturnal rise in bone resorption and formation. The loss of PTH diurnal variation was observed not only in primary hyperparathyroidism, but also in patients with postmenopausal osteoporosis. Continuously elevated concentrations of PTH lead to excessive stimulation of bone resorption, whereas intermittent PTH administration has a strong osteoanabolic effect in patients with osteoporosis. It has not been examined whether the skeletal sensitivity to PTH action depends also on the time of its application. The aim of our study was to verify the hypothesis that the application of teriparatide (TPTD, recombinant human PTH [1-34]) at different times of the day in the context of its diurnal variability affects the physiological circadian rhythm of bone remodeling and also the bone mineral density (BMD) after the long-term TPTD treatment. Fourteen women with postmenopausal osteoporosis treated with 20 micrograms of TPTD daily, applied subcutaneously either in the morning or evening, were included in the first study. The concentration of serum C-terminal telopeptide of type I collagen...
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Frequency of occurrence of selected single nucleotide polymorphisms of CYP2C8 and MDR1 in the Czech population and their influence on the effect of amiodarone
Pechandová, Kristina ; Perlík, František (advisor) ; Král, Jiří (referee) ; Anzenbacher, Pavel (referee)
Frekvence výskytu vybraných bodových polymorfismů CYP2C8 a MDR1 v české populaci a jejich vliv na působení amiodaronu Úvod: Variabilita lékové odpovědi je někdy podmíněna genetickými rozdíly v metabolismu a transportu léčiv. Interindividuální rozdíly jsou často způsobeny polymorfismy, které ovlivňují biotransformační aktivitu enzymů a expresi transportérů. V disertační práci jsme věnovali pozornost cytochromu P450 izoenzymu CYP2C8 a MDR1. Nejprve jsme popsali frekvenci výskytu vybraných variantních alel CYP2C8*2, CYP2C8*3 (2 substituce v exonu 3 a 8, CYP2C8*3G416A a CYP2C8*3A1196G), CYP2C8*4, CYP2C8 P404A u zdravé české populace a variantních alel MDR1 v exonech: 26 C3435T, 21 G2677A/T, 12 C1236T a 17 T-76A. Následně jsme sledovali vliv těchto polymorfismů na působení amiodaronu u vybraného souboru pacientů. Metody: Genotyp MDR1 a CYP2C8 jsme stanovili pomocí PCR-RFLP za využití specifických restrikčních enzymů a primerů. Frekvence genotypů MDR1jsme určili u 189 zdravých dobrovolníků a CYP2C8 u 161 zdravých osob. Do sledování jsme dále zařadili 63 pacientů užívajících amiodaron déle než dva měsíce. Jejich léčbu jsme posuzovali ze záznamů lékařské dokumentace, s využitím standardních biochemických a hematologických vyšetření a záznamů EKG. Koncentrace amiodaronu a jeho metabolitu N-...
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The influence of individual genetic predisposition to the pharmacokinetics and pharmacodynamics of chosen opioids
Matoušková, Olga ; Perlík, František (advisor) ; Votava, Martin (referee) ; Mičuda, Stanislav (referee)
MUDr. Olga Matoušková - the dissertation theses The influence of individual genetic predisposition to the pharmacokinetics and pharmacodynamics of chosen opioids ABSTRACT Introduction: The aim of this thesis is to study the influence of polymorphism of CYP2D6 and MDR1 on the pharmacokinetics and pharmacodynamics of tramadol in healthy volunteers using measurement. A secondary objective is to evaluate these polymorphisms in relation to the analgesic efficacy and side effects of piritramide for acute postoperative pain. Materials and methods: In two prospective work studying the influence of genetic predisposition on the pharmacokinetic and pharmacodynamic parameters of tramadol, we included a total of 90 healthy volunteers. Clinical studies on opioid analgesia and influence of genetic predisposition to the pharmaco-therapeutic effects and side effects in patients with acute postoperative pain, we included a total of 161 patients with acute postoperative pain. Polymorphism genotyping CYP2D6 and MDR1 gene we performed PCR - RFLP analysis, to determine concentrations of tramadol and metabolite, we used gas and liquid chromatography and pharmacodynamic effects of opioids was evaluated by pupilometric measurement and visual analogue scale. Results and conclusion: Variability of the opioid effect is influenced by...
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Antiplatelet therapy in elderly
Paluch, Zoltán ; Alušík, Štefan (advisor) ; Perlík, František (referee) ; Martínek, Arnošt (referee)
The aim of our study was to determine the efficacy of antiplatelet therapy in elderly and polymorbid patients. We were interested to know whether selected laboratory parameters, co-existing conditions, and concomitant therapy may affect the antiplatelet effect of low-dose acetylsalicylic acid. In our study groups, we demonstrated high urinary levels of 11-dehydrothromboxane B2 suggesting ineffective antiplatelet therapy. In our series, its prevalence was in excess of 46%. A comparison of groups of aspirin-sensitive and aspirin-resistant patients revealed statistically significant differences in CRP levels, smoking status, previous stroke, and atrial fibrillation. Patients with effective antiplatelet therapy were more often treated with statins, nitrates, and beta-blockers. Determination of the serum levels of salicylates showed a major role in the high prevalence of ineffective antiplatelet therapy was played by patient non-compliance.
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Genetic variability of drug metabolizing enzymes
Slanař, Ondřej ; Perlík, František (advisor) ; Průša, Richard (referee) ; Lukáš, Milan (referee)
Drug metabolism is one of the key processes allowing to eliminate the administered dose. High interindividual variability of the activity of drug metabolizing enzymes is caused by many genetic and epigenetic factors. This variation can result in substantial differences in clinical response to the drug, ranging from failure of the therapy to appearance of toxic side effects or frequent onset of drug-drug interactions. The aim of the thesis was to evaluate the influence of genetically determined variability in drug metabolizing enzymes activity on the drug pharmacokinetics, pharmacodynemics and to asses whether either phenotyping or genotyping can be effectively applied under the naturalistic conditions of routine clinical practice, for e.g. as a prediction tool during to asses individual risk of development and progress of a disease or to forecast the drug response. The thesis mainly summarizes previously published articles on the topic. We have studied genetically determined variability of tramadol pharmacokinetics as well as drug-induced miosis in healthy volunteers with known CYP2D6 status. The lowest blood concentrations of principal active metabolite O-demethyltramadol accompanied by the highest levels of the parent compound at all sampling intervals up to 12 hours post-dose were found in the...
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