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Effect of iron overload on the induction of apoptosis in mammalian cells
Kabíčková, Tereza ; Balušíková, Kamila (advisor) ; Klíma, Martin (referee)
Iron cations are an important metal ions required to number of essential cell functions. On the other hand, ferrous iron can be very toxic as well. When surplus iron is present in cells, it can catalyze the formation of reactive oxygen species (especially hydroxyl radicals) by Fenton reaction. Iron homeostasis is predominantly regulated by very strict mechanisms on the level of iron uptake into the body. Moreover, iron absorption, transport and storage within the body can be also regulated using complex mechanisms which differ on the level of individual cells and on the level of whole organism. Deregulation of iron homeostasis causing an iron overload and generation of reactive oxygen radicals can evoke serious cell damage leading up to apoptotic cell death. Excess iron storage and subsequent development of oxidative stress can affect lot of different tissues in the body. The organ damages such as fibrosis, cirrhosis, hepatocellular carcinoma, heart failure, loss of β cells and glucose intolerance or diabetes mellitus in patients with iron overload are very often seen. Nevertheless, the apoptosis induced by iron overload has not been well elucidated yet. There are no complex informations about the precise mechanism by which oxidative stress affects different cell types or whether there are other...
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Role of Smarca5 (Snf2h) during transcription of transfected DNA template.
Zikmund, Tomáš ; Stopka, Tomáš (advisor) ; Smetana, Karel (referee)
Cellular and tissue characteristics are results of dynamic regulation of gene expression. DNA wrapped into proteins, referred to as chromatin, requires involvement of mechanisms guiding accessibility of specific sequences. In higher organisms, chromatin remodeling proteins are indispensable in regulating chromatin structure including ISWI ATPase SMARCA5. SMARCA5 is involved in almost any transaction on DNA including transcription, however precise in vivo role of SMARCA5 in these processes remains unknown. To advance understanding of specific role of SMARCA5 in the development of chromatin structure during transcription we devised cellular model in which SMARAC5 level is manipulated while chromatin structure development and transcriptional response are monitored. Our data indicate that the transfected DNA template that is transcribed is enriched with histone H3 and its specific methylation of Histone H3 lysine (K) 4, a mark of active chromatin structure. Overexpression of SMARCA5 results within the reporter gene coding sequence in ~2,5-3 fold increase of both H3 occupancy an its modification H3K4Me3. Increased DNA template commitment into chromatinization is associated with repression of reporter gene expression. These results are supported by studies indicating dynamic development of nucleosomal...
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HPLC Determination of Delta-9-tetrahydrocannabinol
Bažantová, Aneta ; Jezberová, Michaela (advisor) ; Lázníčková, Alice (referee)
Title: HPLC determination of delta-9-tetrahydrocanabinol Author: Aneta Bažantová Supervisor: RNDr. Michaela Hamerníková, Ph.D. Department: Department of Biophysics and Physical Chemistry The aim of my work was to develop a suitable analytical method for forensic application (without heat treatment of examined sample during analysis to prevent an increase of ∆9 -THC content in the sample) to detect delta-9-tetrahydrocanabinol from cannabis. I optimised and validated conditions of high-performance liquid chromatography (HPLC) method for the quantitative analysis of delta-9-tetrahydrocannabinol (∆9 -THC) in the n- hexane extract of marihuana. Quantitation was accomplished with the internal standard (IS) method using beta-17-estardiol acetate. The separation was achieved on a reverse-phase C18 column, using methanol and water (90:10) as mobile phase. The compounds were eluted isocratically at a flow rate of 1ml/min. The compounds were analyzed with fluorescence detection at 220nm/317nm. The retention time of ∆9 -THC and the IS was 9.97min and 5.25 min, respectively, and the total run time of the assay was around 10 min.The validation characteristics included linearity, accuracy, precision, limit of detection and quantification and robustness. The calibration curve was linear over the range of...
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Determination of mechanical properties from microcompression test
Truhlář, Michal ; Kruml, Tomáš ; Kuběna, Ivo ; Petráčková, Klára ; Náhlík, Luboš
This paper describes a microcompression test of Al - 1.5 wt. % Cu thin film deposited on Si substrate. Microcompression combines the sample preparation with the use of ion focused beam (FIB) with a compression test carried out using nanoindenter. Cylindrical specimens (pillars) were prepared using FIB. The diameter of pillars was about 1.3 μm and their height was about 2 μm (equal to the film thickness). Stress-strain curves of the thin film were obtained. The results depend on crystallographic orientation of pillar. The paper is focused to an attempt to determine as precisely as possible Young modulus of the film using experimental data and finite element modelling.
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Application of chromatographic methods for the separation of metabolites of cholesterol
Tetřevová, Lucie ; Nováková, Lucie (advisor) ; Šatínský, Dalibor (referee)
Author: Bc. Lucie Tetrevová Title: The application of chromatographic methods for separtion metabolites of cholesterol Language: czech The proposed diploma thesis deals with the development and validation of analytical method for free and esterified cholesterol separation from blood serum and adrenal tissue samples. This method is neccessary due to the different metabolism of free and esterified cholesterol in the body and it enables the research of these particular pathways using stable isotope tracers. The solid phase extraction method was chosen, optimised and validated with following results: precision values 2.14% for serum cholesterol ester, 6.98% for tissue cholesterol esters, 2.91% for serum free cholesterol, 7.48% for tissue free cholesterol, limit of detection 1 mol/l and linear range 1-25 mmol/l were found. The stability of the derivative was tested for 30 days at temperatures 4 C and -25 C. The derivative was found to be stable for the whole time period in both temperatures. Laboratory temperature was not tested due to a high volatility of the solvent used. The developed method was used in experimental studies evaluating the influence of dietary cholesterol and septic shock to cholesterol synthesis rate.
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Plasma-jet systems - experiment and model
Rubovič, Peter ; Kudrna, Pavel (advisor) ; Hubička, Zdeněk (referee)
In the present work we study the ow of working gas through a plasmajet system. In this work we describe the basic principle of hollow cathode discharge and its use for technological applications, mainly for thin layers coating. One of the important parameters during the deposition is the speed of the working gas ow and with it the sputtered target material towards the substrate. Because of the reproducibility and precision of the experiments it is important to know the relation between the working gas ow and external parameters of the experiment, e.g. ow of the gas and the pressure in the chamber. This is the reason why measurements of ions velocity using Langmuire electrostatic probe and pulse regime of plasmajet were done. Measured data are compared with a computer model, which was developed in this work. This model describes the ow of the working gas by solving Navier-Stokes equation for compressible Newtonian uids. The results of this model are compared with results from the paper describing the ow through the hollow cathode. It shows good agreement inside the cathode. The model is giving dierent results when comparing to measured data which are from the area outside the cathode. Part of the model description is a discussion of the temperature dependence of the ow.
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Analysis of the internal environment of the selected organization
KURFIRSTOVÁ, Linda
The aim of my thesis is to reveal the facts relating to the current situation in the selected company, namely through the analysis of the internal environment. The facts discovered will then serve for the design of optimal strategy that will improve the company's strengths and eliminate its weaknesses. The first conducted analysis was that of portfolio, Boston matrix, which is often used in practice precisely because it will give us the answer to the question as to what business activities have the potential for the company and which, on the other hand, have disadvantages and just swallow its resources. Thanks to its design, we can also assess the current situation of the market and take necessary action in its development field and thus gain greater competitive advantage. Analysis of corporate finances is usually implemented using financial analysis; and data needed for the development was obtained from the balance sheet and the profit and loss account.I decided to work with indicators according to the method of Rolf Grünwald (2007). These are indicators of liquidity, profitability, activity and subsequent debt. The last used method is the SWOT method, which was based on the identified strengths and weaknesses of the company as well as its opportunities and threats - only some of those were chosen and used to build Fuller triangle through which I could calculate the weight of individual factors and therefore determine the position of the company in the SWOT matrix. Boston matrix discovered that the company?s position against its strongest competitor is not bad. It just needs to focus on the involvement of such material that will ensure stable profits ? in another words material that will, in the matrix, appear in the position of dairy cow. Financial analysis found some problems in the area of ability to meet its obligations and, therefore, the company should focus on this situation. Furthermore it is far too dependent on foreign sources, which does not help much in the event of future needs of obtaining funds. SWOT analysis of the company testified that if it is able to utilize the strengths it has at its disposal, it will be able to remove the threats faced in the market, and therefore find itself in a better situation in the future. This will work to the company?s advantage simply because there are not many companies with this strategy on the market at this present time. Many businesses simply do not have such strengths at their disposal.
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Nano modification of the W(100)/ZrO electron emitter tip using reactive ion etching
Horáček, Miroslav ; Matějka, František ; Kolařík, Vladimír ; Matějka, Milan ; Urbánek, Michal
The W(100)/ZrO electron emitter tip is typically prepared from a tungsten single-crystal shaft of a diameter of 125 μm using electrochemical anodic etching. In order to prepare an emitter for e-beam writer with a shaped beam it is desirable to etch the tip with a radius around 100 nm. Despite the anodic etching is precisely controlled using dedicated software, the desired final form shape of the emitter tip is not achieved in every case. The correcting anodic etching is not possible due to the technology principle of the etching itself. We present in this contribution the procedure that modifies/repairs the tungsten tip shape in a nanoscale region using a reactive ion etching (RIE) in CF4 + O2 gaseous mix in a barrel type reactor at the radio frequency of 13,56 MHz and the working pressure of 1000 Pa. The change of the geometry after the RIE process is checked using a high resolution scanning electron microscope. The influence of the tip modification of the activated thermal-field W(100)/ZrO electron emitter on its emission characteristics is also presented.
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Parameter identification of the asynchronous machine substituting circuit
Otýpka, Jan ; Běloušek, Josef (referee) ; Patočka, Miroslav (advisor)
This work deals the precise identification of the substituting circuit parameters of the asynchronous machine for the gama-network, inverted Gama-network, T-network. I make use the best identification of the substituting circuit parameters of the asynchronous machine experimental method, theoretical procedurs and konstruction dates. In this work I solve various methods of identification and i compare solving like construction moment's characteristics from these establishen parametrs. Further I'm solving in my work comparations of two the costruction of them is similar with asyhronous mashins with power of 2,2kW , 2p = 2.
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Metabotropic glutamate receptors: mechanism of activation
Hlaváčková, Veronika ; Blahoš, Jaroslav (advisor) ; Vyklický, Ladislav (referee) ; Martásek, Pavel (referee) ; Konvalinka, Jan (referee)
Any living organism receives constantly many signals that have to be evaluated and weighted to respond in an appropriate way. To perform all functions needed for precise control of homeostasis and for communication with the surrounding environment, signals coming from the outside are recognized and transferred into modulation of intracellular signaling cascades. These mediate response to the extracellular stimulus as well as intercellular communication. Cell communication is mediated by several types of receptors, located either intracellularly (including nuclear receptors) that modulate gene transcription and receptors localized on plasma membrane. Cell membrane receptors are transmembrane proteins that are divided into three superfamilies according to their structure and principles of signal transduction. These are ion channel-linked receptors, enzyme-linked receptors and G-protein-coupled receptors (GPCRs). GPCRs comprise the biggest family of membrane receptors and are one of the largest gene families in general. They are encoded by about 1% of genes in mammals. Many of them bind sensory ligands (rhodopsin, taste and olfactory receptors), but others also recognize ions, amino acids, nucleotides, peptides and large glycoproteins (1). They play a crucial role in such distant physiological functions as...
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