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Electrogram processing and analysis
Hanák, Pavel ; Kolářová, Jana (referee) ; Janoušek, Oto (advisor)
The aim of the study was focused on problem of electrograms recording from alive tissue. Study of electrograms recording was extended with noise analysis and its elimination. Elimination of noise and disturption was made in program Matlab; lowpass filtration and wavelet transformation was used. Application for electrograms analysis was developed in latter part of this work.
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Measurement of Isolated Cardiac Muscle Cell Lenght in real time
Klabal, Petr ; Sekora, Jiří (referee) ; Chmelař, Milan (advisor)
Diploma thesis deals with the basic description of cardiac muscle cells, the mechanism of its contraction and events associated with contractions. There are different types of methods which can be used for measuring of contractions and for evaluation of cell length. This work describe these methods and evaluate their pros and cons. Based on available information and technical possibilities is one of the methods chosen and used for the design of block diagram system for measuring of contraction of isolated heart cells in real time. The practical part of this diploma thesis deals with the designing of a system which allows processing the image of isolated cardiac muscle cells that facilitate the detection of the cells edge. For this purpose it was created a device that allows the user to select a single row from television signal containing the image information from a location where is the currently selected row. Thus obtained image information can be used for cells edge detection and measuring of its length and contractions.
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Optical Measurement of Electromechanical Characteristics of Heart Cells
Čmiel, Vratislav ; Križanová,, Olga (referee) ; Babula, Petr (referee) ; Provazník, Ivo (advisor)
Dissertation is focused on the application of optical measurement methods using techniques of optical microscopy and fluorescence microscopy in measurements of electromechanical characteristics of isolated cardiac cells and clusters of differentiated cardiomyocytes. The first proposed method uses a practical combination of fluorescence microscopy equipped with fluorescent fast and high-resolution camera and atomic force microscopy for simultaneous measurement of calcium transients and contraction of cardiomyocyte clusters. The signals obtained undergoes filtration, processing and analysis. Result function parameters obtained by analyzing signals after application of caffeine are evaluated by comparison with functional parameters obtained during the control measurement. The second proposed method is applied to the cardiomyocyte clusters for the purpose of cardiomyocyte contraction signals measurement. The signals obtained by optical methods are analyzed and compared with the reference signal obtained using atomic force microscopy. Optical measurement method of cell contractins based on detection of cell ends using adjusting of microscopy images by re-sharpening and fluorescence method for cardiomyocyte contractions measurements were designed to increase realiability in simultaneous measurement of cell contractions simultaneously with calcium transients in isolated cardiomyocytes experiments.
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Optical Method to Evaluate the Contractile Function of Isolated Cardiac Myocytes
Kopečný, Josef ; Harabiš, Vratislav (referee) ; Čmiel, Vratislav (advisor)
In this master´s thesis we will firstly focused on the description of a cyte in terms of structure as well as in terms of electrical and chemical processes. We will examine a processes, which make a contraction and the processes on cyte membrane. We will also analyse image processing methods and methods for measuring the contraction. The block diagram will be designed and requirements for the measuring platform will be specified. The programme will be realized in LabWIEV programming language.
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Dynamic Programming in Biosignal Processing
Procházka, Petr ; Kolářová, Jana (referee) ; Klimek, Martin (advisor)
Bachelor thesis describes the dynamic time warping method (DTW), which is used for extrasystoles detection in ECG signales. Several methods for extracting a reference cycle are described in this paper. These methods are applied either to whole heart cycles or just to QRS complexes. Afterwards these methods are compared with results of cluster analysis.
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Device for measuring the electrical activity of muscles
Slouka, Petr ; Chmelař, Milan (referee) ; Balogh, Jaroslav (advisor)
This thesis contains introduction to the basic principles of creation and transmission of action potentials. Afterwards it is outlined development of electromyography which is used for measuring electrical signals from muscles and attributes of electromyographic signal. Next part describes design of the device for measuring electrical activity of muscles. Thesis contains diagrams of the integrated circuit, design of printed circuit board and list of components which are needed for realization of the device.
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Optical detection of electrograms
Hanák, Pavel ; Kozumplík, Jiří (referee) ; Chmelař, Milan (advisor)
The aim of the study was focused on problem of electrograms recording with using voltage sensitive dyes. Study of electrograms recording was extended with thema of optical detectors suitable for measurement and noise analysis. Elimination of noise and disturption was made in program Matlab; lowpass filtration and wavelet transformation was used. Application for electrograms analysis was developed in latter part of this work.
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Simulation of action potentials and membrane currents by solving Hodgkin and Huxley equations
Bugnerová, Pavla ; Provazník, Ivo (referee) ; Chmelíková, Larisa (advisor)
The thesis deals with the analysis of the resting membrane potential and action potential mainly on the cell membrane of cardiac cells. Attention is given to the electrical schematic layout of the cell membrane and distribution of current part on the main components. The basis for the creation of a mathematical model and simulation is the differential equations of Hodgkin and Huxley. To the description them of calcium and potassium channel leakage from other models are added. The project explores the possibilities of reproducing the known development of membrane currents in two basic modes (voltage clamp and current clamp). All in user interface MATLAB GUI.
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3D Model of Cardial Tissue Electrical Propagation
Míková, Monika ; Mézl, Martin (referee) ; Hejč, Jakub (advisor)
The aim of this master thesis is to create a simple 3D electro-anatomical model of cardiac tissue that will be able to simulate the electrical activation in both a healthy heart and a heart with arrhytmogenic substrate. The model of electrical activation is realized in the COMSOL Multiphysics, simulation software for modelling using the finite element method. The Fitzhugh-Nagumo equation was used to model the excitatory feature of the myocardium and 2D models of myocardial tissue describing the propagation of action potential in healthy tissue, ischemic tissue, spontaneous action potential formation in the SA node, and spiral wave formation were first developed based on appropriate parameters. Subsequently, simplified 3D models of the heart describing the spread of excitement in a healthy heart, in the presence of accessory pathway and in third-degree atrioventricular block were created. The simplified 3D heart model offers a compromise between computational load and model complexity and can be used as a diagnostic tool for tissue and whole heart adjustment with appropriate equation parameter settings.
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New Approaches in Cardiac Optical Mapping
Švrček, Martin ; Kizek, René (referee) ; Sovka, Pavel (referee) ; Provazník, Ivo (advisor)
This dissertation deals with new approaches in cardiac optical mapping. The principle of cardiac optical mapping as well as the current research in this field was described. The new measurement system was developed and its characteristics presented. The system design allows epicardial and endocardial mapping, employing new ratiometric techniques in 2D acquisition and simultaneous electrical and optical mapping. The measured characteristics of fluorescent dye di-4-ANEPPSS were presented. The relation between movement and consequent motion artifacts is well described. Several new approaches in signal processing were proposed, including new ratiometry technique and using image registration to suppress motion artifacts. The algorithm for elastic image registration of optical signals and innovative method for verification of registration process were presented. Application of all proposed approaches and its results are included and discussed.
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