|
|
Circulating tumor DNA in urine and its use as a potential biomarker of colorectal cancer
Surkovová, Veronika ; Ptáčková, Renata (advisor) ; Dračínská, Helena (referee)
Colorectal cancer (CRC) is a serious disease whose incidence has been steadily increasing. There is a high chance of cure and a good quality of life, if the treatment is started in the early stages of this disease. The so-called liquid biopsy, in which biomarkers from various body fluids are obtained and analyzed, could help with early detection of the disease, monitoring of the patient's condition and appropriate determination of the diagnosis. The aim of this study is to isolate and analyse circulating tumor DNA (ctDNA) from the urine of patients with advanced CRC. In these patients the ctDNA was detected in plasma. The method used for analysis is based on the principle of PCR with the formation of heteroduplexes, followed by the separation of "wild type" and mutated DNA fragments by denaturing capillary electrophoresis. Unlike plasma samples, the presence of KRAS mutations was not confirmed in urine samples. Neither the established procedure for plasma analysis, the attempt to enrich ctDNA by so-called purification, nor other tested isolation kits using the selected detection method allowed detection of the KRAS mutation in urine via ctDNA. Although urine ctDNA testing in general appears to be a promising method for improving the treatment level of (colorectal) cancer, and although its use could...
|
|
|
Effect of rat enzymes on the metabolism of tyrosine kinase inhibitors in vitro and in vivo
Škriabová, Simona ; Indra, Radek (advisor) ; Ptáčková, Renata (referee)
Tyrosine kinase inhibitors are small molecules, orally available, well-tolerated and globally approved drugs for the treatment of several types of tumors. These drugs include vandetanib, cabozantinib, and lenvatinib, which are used to treat thyroid cancer. Vandetanib and cabozantinib are drugs approved for the treatment of medullary thyroid cancer, and lenvatinib is approved for the treatment of differentiated thyroid cancer. In the presented diploma thesis, the in vitro and in vivo metabolism of vandetanib, cabozantinib and lenvatinib was studied. Microsomes isolated from the liver of rats premedicated with pregnenolone carbonitrile were used to study in vitro metabolism. Plasma and urine samples of rats premedicated with individual tyrosine kinase inhibitors were used to study in vivo metabolism. The resulting metabolites were analyzed by high-performance liquid chromatography and subsequently identified using the mass spectrometry method. In the study of in vitro metabolism, when NADPH and cofactors (glucuronic acid and glutathione) were added to the samples, it was found that the most metabolites appeared for all three drugs during a longer incubation periods, and at the same time, it was found that glucuronic acid and glutathione can influence the structure, properties and functions of the...
|
|
|
Inhibitory effect of endocrine disruptor 17α-ethinylestradiol on cytochrome P450 subfamily 1A
Kurshakova, Evgeniia ; Dračínská, Helena (advisor) ; Ptáčková, Renata (referee)
17-ethinylestradiol (EE2) is a synthetic derivative of the natural estrogen 17-estradiol. It is used in medicine as a key component of oral contraceptives. Due to its ability to modulate the functions of the endocrine system, EE2 belongs to the group of endocrine disruptors. The ability to bioaccumulate and affect the reproduction and development of wildlife makes EE2 a compound that possesses a potential environmental risk. Cytochromes P450 1A1 and 1A2 catalyze the oxidative reactions in metabolism of exogenous compounds, including EE2. 17-Ethinylestradiol is known to have a strong inhibitory effect on the isoform CYP1A1. Within the framework of the present thesis, the inhibition effect of EE2 on the activity of cytochromes P450 of subfamily 1A was studied in vitro via three marker reactions: 7-methoxyresorfin O-demethylation, 7-ethoxyresorufin O-deethylation and phenacetin O-deethylation, which had to be pre-optimised for the following uses. A highly selective inhibitory effect of 17-ethinylestradiol on the human and rat isoform CYP1A1 was confirmed. An inhibitory effect on the activity of the CYP1A2 isoform was not observed by any of marker reactions. Using phenacetin O-deethylation, the concentration of EE2 causing 50% inhibition of CYP1A1 (IC50) was also determined, being of 3,4 M, at a...
|
|
|
Pošta pro tebe-reality TV and social motivation of participations
Ptáčková, Renáta ; Bednařík, Petr (advisor) ; Gerbery, Juraj (referee)
Abstrakt_anglicky _Diplomova_prace_Ptackova_Renata The diploma thesis "Pošta pro Tebe - reality TV and social motivation of participants" focus on the use of social television. It describes in detail the reality TV genre, its brief history of broadcasting, focusing on the motivational elements of the program participants Pošta pro Tebe. It investigates the impact and effect of media and mediated relationship to the contents of a reality. It analysis the audience base, explores reasons for visiting the TV studio spectators, why people looking for this TV show and why they watch it by questionnaires, interviews. It's looking for the credibility of the program and asking whether the audience would become program participants. Further, the work captures the audience ratings and popularity in each year of its broadcast. Finally, describes the creation of the show and behind the scenes. The diploma thesis is divided into 4 chapters: Theoretical introduction thesis (clarifying the concepts that are crucial for the work related), Ratings (analyzing rating charts of the first channel of Czech Television and the demographic composition of the audience), Behind the Scenes program (described shooting of, the role of interested participants, technical background of the show), Audience (defines who is the audience and...
|
|
|
Characterization of hapt oglobin glycoforms in human serum
Darebná, Petra ; Pompach, Petr (advisor) ; Ptáčková, Renata (referee)
Characterization of haptoglobin glycoforms in human serum Petra Darebná (Katedra biochemie, Přírodovědecká fakulta, Univerzita Karlova v Praze, Česká republika) Changes in glycosylation of proteins are associated with several types of cancer, including hepatocelular carcinoma and colorectal carcinoma. This project deals with data independent analysis using ion cyclotron resonance with Fourier transform and tandem mass spectrometry with liquid chromatogramy and multiple reaction monitoring to quantify these changes in hepatocelular cancinoma and colorectal carcinoma with liver metastases. In the first part of the project the haptoglobin was enriched from pooled serum samples of pacients with hepatocellular carcinoma, colorectal cancer and colorectal carcinoma with metastases using hemoglobin immobilized on CNBr-activated Sepharose 4B and then purified by high pressure liquid chromatography. Individual haptoglobin glycopeptides were analyzed using ion cyclotron resonance with Fourier transform. In the second part of the project we analyzed changes in glycosylation depending on diferent tumor diseases in partially depleted serum of individual patients using ethanol precipitation. Individual fucosylated glycoforms of N-glycopeptides of serum proteins were compared with their nonfucosylated forms. In...
|
|
|
Structural characterization of Nkr-p1f/Clrg interaction
Tůmová, Lucie ; Kavan, Daniel (advisor) ; Ptáčková, Renata (referee)
NK cells are ranked among lymphocytes, which are involved in primary immune responses to virus infected and tumour cells. They produce cytokines at the same time and are involved in the formation of secondary immune responses together with T and B lymphocytes. This diploma thesis is engaged in the study of the structure and interaction of the transmembrane receptor Nkr-p1f with its ligand Clr-g. This receptor Nkr-p1f has an activation function and is able to initiate the cytotoxic function of the NK cells. The three-dimensional structure has been solved as a Clr-g homodimer, but its interaction with the Nkr-p1f receptor remains mysterious. The aim was to prepare an expression vector coding the entire extracellular region of the receptor NKR-P1F and carry out the production of the receptor Nkr-p1f and Clr-g in prokaryotic expression system, subsequently renaturation and purification of the proteins in vitro. This way prepared proteins were analyzed by electrophoresis and mass spectrometry. Their interaction was studied with biophysical method, surface plasmon resonance (SPR). However, the interaction between them was not revealed by SPR technology. (In Czech)
|
|
|
Television Christmas - comparison of television programme offered during the Christmas feasts in last 10 years
Ptáčková, Renáta ; Reifová, Irena (advisor) ; Bednařík, Petr (referee)
Bachelor's thesis "Television Christmas - comparison of television programme offered during the Christmas feasts in last 10 years" target the analysis of particular genres in term of frequency and length in television programme. Special attention comes in on fairy tales, serials and news. The thesis is for example interested in the fact, if the serials don't dominate above the fairy tales or what is the frequency of broadcast news in television stations. Then the thesis solves how the television structure was formed, who controlled the prime time and which fairy tale or film won audience over. For methodology of thesis was used quantitative analysis of television programmes in prime time during the Christmas feasts 1997-2006. Bachelor's thesis is structured in 6 chapters: Theoretical introduction of thesis (show up the notions, which are keyword for the theme), Quantitative analysis of sampled television programmes (process the theme by tables and graphs, Prime time News (progress and frequency of broadcast news during the 10-years term and progress during the holidays), Serials and last chapter is Progress of fairy tales, news and serials in 1997-2006 (grand summary of three the most significance television genre during Christmas). The end of the thesis is enriched by photos of the most famous...
|
|
|
Effect of cytochromes P450 on metabolism of anticancer drugs bound into apoferritin nanoparticle
Wilhelm, Marek ; Indra, Radek (advisor) ; Ptáčková, Renata (referee)
Tumour-related diseases are the second most common cause of death in the Czech Republic, right after cardiovascular diseases. Nanomedicine - a novel scientific discipline - shows captivating potential in anticancer treatment with help of so called nanotranporters - nanoparticles capable of transporting other molecules. Encapsulation of a cytostatic drug into a nanoparticle improves its pharmacokinetical and pharmacodynamical properties which helps to reduce adverse side effects on non-tumour healthy tissue. In the scope of this diploma thesis apoferritin - apo-form of ferritin - was studied, since this nanotransporter shows promise for clinical use in anticancer treatment. Effect of hepatic microsomes from premedicated and control rats on biotransformation of doxorubicin cytostatic (Dox) in free and apoferritin nanoparticle-bound forms was investigated at pH 7,4. Over the course of biotransformation two types of metabolites - M1 and M2 - were observed. Regardless of the employed inductor all studied microsomes have exhibited similar metabolism of free doxorubicin and its apoferritin encapsulated form (ApoDox). Our results also imply that doxorubicin can be metabolically processed by rat hepatic microsomes in both free and ApoDox form with similar efficiency. We have also studied biotransformation...
|
|
|
Expression and purification of protein containing photo-methionine - the use of photo-induced cross-linking to map protein-protein interaction
Tichá, Andrea ; Ptáčková, Renata (advisor) ; Indra, Radek (referee)
Protein 14-3-3ζ is an important protein that plays a role in the regulation of cell survival and keeps cell from stress and possible apoptosis. A photo-activatable group can be incorporated into the protein to detect protein-protein interaction by photo induced crosslinking. The aim of this work was to create protein with incorporated photo-methionine in auxotrophic bacteria E. coli B834 and to optimize expression conditions. Photo-methionine is structurally very similar to natural methionine, so photo-methionine can be incorporated into the protein by host aminoacyl tRNA synthetase. It has been studied how the rate of incorporation varies depending on production time. After 3 or 6 hours, up to 70 % incorporation of photo-methionine was achieved compared to about 50 % after one hour.
|
|
| |
guest ::
RSS feed.