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Role of drug transporters in placental transfer of entecavir
Křečková, Veronika ; Červený, Lukáš (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Veronika Křečková Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Role of drug transporters in placental transfer of entecavir Entecavir (ETV), an analogue of guanosine, is a highly efficient anti-hepatitis B antiviral drug. It is the first-line therapy for both adults and children. Its use in pregnancy is limited due to a number of factors, including lack of data on placental pharmacokinetics. The placental transition of drugs is frequently controlled by drug transporters. ATP-binding (ABC) transporters, P-glycoprotein (P-gp), breast cancer resistance protein (BCRP) or multidrug resistance-associated protein 2 (MRP2) localized in the apical membrane of syncytiotrophoblast and pumping their substrates in the feto-maternal direction belong to most significant determinants of placental pharmacokinetics. Moreover placental transport of nucleoside-derived drugs can be affected by the activity of nucleoside transporters (NTs); equilibrative nucleoside transporters (ENTs) mediate facilitated diffussion, while the concentrative nucleoside transporters (CNTs) control active influx of their substrates. The aim of the diploma thesis was to describe the role of P-gp, BCRP, MRP2 and NTs (ENTs and...
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Study of drug-drug interactions of antiviral drugs on intestinal transporters
Záboj, Zdeněk ; Červený, Lukáš (advisor) ; Vokřál, Ivan (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Zdeněk Záboj Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Study of drugs interactions of antiviral drugs with intestinal transporters Sofosbuvir is an antiviral agent widely used in the treatment of chronic hepatitis C. This orally administered prodrug is a designed substrate of ATP-binding (ABC) efflux transporters, P- glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2). ABCB1 and ABCG2 are important determinants of intestinal absorption and are the site of significant pharmacokinetic drug interactions, leading to changes in drug exposure. Pharmacokinetic drug interactions may be undesirable (increasing the toxicity of the treatment) or desirable (allowing dose reduction). Because sofosbuvir is often administered in combination regimens with other anti(retro)virotics, the aim of this thesis was to study the ability to enhance intestinal absorption of sofosbuvir. To study the pharmacokinetic drug interactions on ABCB1 and ABCG2, a widely established in vitro bi-directional transport method through a polarized monolayer formed by the Caco-2 cell line derived from colorectal cancer has been used. We analyzed the drug interactions of sofosbuvir on these efflux...
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Pharmacokinetics of ivermectin in the sheep feces
Sobotová, Dominika ; Vokřál, Ivan (advisor) ; Lamka, Jiří (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Dominika Sobotová Tutor: PharmDr. Ivan Vokřál, Ph.D. Title of diploma thesis: Pharmacokinetics of ivermectin in the sheep feces Key words: ivermectin, pharmacokinetics, sheep, anthelminthic Infection with internal parasites (endoparasites) is one of the most common diseases in sheep. Infection with these parasites mainly with the barber's pole worm (Haemonchus contortus) causes considerable economic losses and has a significant impact on sheep productivity. Anthelmintics, including ivermectin, are used for treatment. Ivermectin belongs to the class of macrocyclic lactones and is characterised by broad spectrum and low toxicity. On the other hand, it poses a risk to the environment in form of residues that are excreted in feces by treated individuals. The aim of this study was to determine the excretion profile of ivermectin in sheep subcutaneously administered in a standard dose 0,2 mg/kg of body weight. UHPLC/MS/MS method was used for the analysis of ivermectin fecal concentration. Based on the obtained results we determined basic pharmacokinetic parameters which includes time to achieve maximum concentration (tmax), maximum concentration (cmax), area under the curve (AUC) and mean residence...
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Evaluation of rationality and risks of pharmacotherapyin older patients in long-term care facilities
Lukačišinová, Anna ; Fialová, Daniela (advisor) ; Alušík, Štefan (referee) ; Paluch, Zoltán (referee)
Objectives Main objectives of this doctoral thesis were to review available information on pharmacological properties of benzodiazepines and their age-related changes; to evaluate the prevalence of benzodiazepine use in older patients residing in long term care facilities; to investigate the association between use of benzodiazepines and occurrence of falls in acutely hospitalized older patients; and to describe utilization of benzodiazepines in the Czech Republic. Methods A narrative review of literature focused on pharmacokinetics, pharmacodynamics, adverse effects and association of benzodiazepines with falls in older population was conducted. The evaluation of benzodiazepine use in long term care facilities was analysed in a retrospective cross-sectional study using data from the EC 7th Framework Program SHELTER project (Service and Health in the Elderly in Long Term Care). A prospective cohort study data of acutely hospitalized patients in Australia were used to evaluate association between benzodiazepines and falls. To describe utilization of benzodiazepines in the Czech Republic, data from the State Institute for Drug Control and from databases of General Health Insurance Fund were used. This dissertation thesis is a summary of published articles from above stated works and analyses. Results...
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Mathematics and implementations of physiologically based pharmacokinetic modeling
Rakhimov, Yestay ; Duintjer Tebbens, Erik Jurjen (advisor) ; Klemera, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Kr'alov'e Department of Biophysics and Physical Chemistry Candidate: Yestay Rakhimov Supervisor: doc. Erik Jurjen Duintjer Tebbens, Ph.D. Title of diploma thesis: Mathematics and implementations of physiologically based phar- macokinetic modeling The thesis addresses some basic aspects of pharmacokinetic modeling, which is used to describe pharmacokinetic processes. Understanding these processes is important for example to determine optimal concentrations of drugs dosing. The thesis focuses on mathematical proofs of a number of pharmacokinetic equa- tions, which are often not given in standard books. The derived equations are illustrated with numerical experiments for a particular drug in the software PharmCalcCl and MAT- LAB. 4
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Geometric Semantic Genetic Programming
Končal, Ondřej ; Bidlo, Michal (referee) ; Sekanina, Lukáš (advisor)
This thesis examines a conversion of a solution produced by geometric semantic genetic programming (GSGP) to an instantion of cartesian genetic programming (CGP). GSGP has proven its quality to create complex mathematical models; however, the size of these models can get problematically large. CGP, on the other hand, is able to reduce the size of given models. This thesis combinated these methods to create a subtree CGP (SCGP). The SCGP uses an output of GSGP as an input and the evolution is performed using the CGP. Experiments performed on four pharmacokinetic tasks have shown that the SCGP is able to reduce the solution size in every case. Overfitting was detected in one out of four test problems.
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Disposition of New Synthetic Drugs in The Organism. Pharmacokinetics and Biotransformation Study. Toxicological Detection in Biological Materials.
Židková, Monika ; Balíková, Marie (advisor) ; Šustková, Magdaléna (referee) ; Šanda, Miloslav (referee)
The object of this thesis was the study on the pharmacokinetics and biotransformation of selected abused new synthetic drugs, specifically belonging to cathinone and aminoindane groups, in experimental rats. This work consisted of two parts: a biotransformation study of mephedrone, methylone, 5,6-methylenedioxy-2- aminoindane (MDAI) and a distribution profile study of mephedrone, methylone, MDAI and naphyrone. This document is presented as a commentary to the original papers, which were published in peer reviewed journals. The samples of blood and tissue (brain, lungs, liver) were taken at specific times after a subcutaneous single bolus dose of the studied drugs. The urine samples for the biotransformation studies were collected over a 24-hour period following the sc. dose. The LC/HRMS method was used for metabolite detection and quantitative analysis. Our findings not only included testing metabolites of the aforementioneddrugs against the synthesized reference standards, but also discovering previously unknown metabolites of these drugs. Ten phase I and five phase II metabolites aside from the parent drug were identified in urine after mephedrone administration by comparison of their spectra against those of reference standards and/or MS2 spectra of previously identified metabolites. The main...
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The pharmacokinetics of isoflavonoides
Ungerová, Lucie ; Pourová, Jana (advisor) ; Mladěnka, Přemysl (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Lucie Ungerová Supervisor: PharmDr. Jana Pourová, Ph.D. Title of diploma thesis: The pharmakokinetics of isoflavonoids The aim of this diploma thesis is to summarize currently available informations about the pharmacokinetics of the polyfenolic compounds from a large group of flavonoids, isoflavonoids. Isoflavonoids are coumpounds found in many plant families, but especially in some members of Fabaceae family. One of the main well-known sources are soy beans containing the most famous isoflavones - genistein and daidzein, their pharmakokinetics is the main theme of this diploma thesis. Since isoflavonoids are mainly contained in the diet, their oral administration is very relevant. Isoflanonoids in the human diet occurs predominantly in the form of glykosides and therefore, after ingestion, they have to be deglycosylated by β- glucosidase enzyme family to aglycones. After that they are able to pass through the intestine into the systemic circulation and they are available for action. This is already happening in the oral cavity and the absorption occurs in the small intestine. The intestinal bacterial microflora composition is also very important for pharmacokinetics, for example I can mention...
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Study on interaction potential of maraviroc with drug transporters ABCB1 and ABCG2
Erbenová, Kateřina ; Čečková, Martina (advisor) ; Červený, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Kateřina Erbenová Supervisor: PharmDr. Martina Čečková, Ph.D. Title of diploma thesis: Study of interactions antiretroviral drug maraviroc with drug transporters ABCB1 and ABCG2. Maraviroc is inhibitor of CCR5 HIV virus entry into the cells representing one of the important components of antiretroviral therapy. To optimize the treatment strategies and minimize the therapeutic risks of maraviroc-containing combination antiretroviral therapy, it is important to know the interactions of this drug with other antiretrovirals. In particular, interaction on membrane transporters may affect pharmacokinetics and thereby the tissue concentrations of administered drugs, leading to insufficient efficacy of the therapy or increased toxicity. The aim of this study was to experimentally evaluate interaction of maraviroc with the two most important active drug transporters of the ABC transporter superfamily, ABCB1 (P-glycoprotein) and ABCG2 (BCRP). Using in vitro methods employing cell lines we aimed to fulfil two main goals: (1) to evaluate the inhibitory effect of maraviroc on ABCB1 and ABCG2 transporters and (2) to study if any of these transporters could transfer maraviroc as their substrate. The data...
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Factors affecting drug distribution and elimination and their application in personalized pharmacotherapy.
Šíma, Martin ; Slanař, Ondřej (advisor) ; Juřica, Jan (referee) ; Tesfaye, Hundie (referee)
The aim of this dissertation thesis was to study the factors affecting drug distribution and elimination and to use these factors to individualize dosing. The work consists of three thematic areas: estimation of the volume of distribution and subsequent dosing of selected drugs (vancomycin, amikacin, phenobarbital) using body size descriptors; estimation of clearance and subsequent dosing of selected drugs (vancomycin, amikacin, phenobarbital, perindopril) using renal function status markers; and the impact of drug interactions on the distribution and elimination of phenobarbital. The thesis summarizes original papers on these topics. Individual pharmacokinetic parameters were calculated for each patient based on their demographic and clinical characteristics, dosing records and measured serum drug levels. The relationships between distribution volume/drug clearance and body size descriptors/renal functional status markers were examined by regression analysis. Vancomycin volume of distribution was best predicted by the total body weight. Loading dose of 10.7 mg/kg of total body weight was optimal in patients taking continuous vancomycin and would lead to reducing of median time to reach target concentrations from 17 to 1 hour. On the contrary, amikacin volume of distribution was most associated...
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