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Morphology of the Abdominal Aortic Aneurysm
Eberlová, Lada ; Valenta, Jiří (advisor) ; Stingl, Josef (referee) ; Šebesta, Pavel (referee)
Dissertation Abstract Abdominalaortic aneurysm (AAA) is a serious disease. Its prevalence is in the developed countries about 3%. As an aneurysm is considered a dilatation of all layers of a vessel wall over 3 cm. Majority of AAA are small and asymptomatic, and although the risk of rupture increases with the size of aneurysm sack, even the small aneurysms rupture. The rupture mortaliry ranges about 70 %. Surgical treatment is indicated in the asymptomatic patients in diameter of AAA over 5 cm. The average speed of growth of AAA is 0.3 cm per year, e.g. in the early diagnosed patients there is a several years interval for a pharmacolocical influencing of the progression of this disease. Knowledge of pathogenesis is essential for any targeted pharmacological treatment. Our prospective, non-randomised studies are based on the application of the stereological methods for the histopathological assessment of the AAA samples. The acquired data enable the statistical analysis, including the null hypothesis testing. In our study analyzing the histopathology of AAA aortae of 65 patients (65 walls and 55 thrombi) and 6 normal abdominal aortae from the organ donors we assessed the following parameters: the area fractions of collagen and elastin, and the length density of elastin in intima and media, the area...
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Quantification of Perfusion using MRI ASL Methods
Kolajová, Martina ; Mézl, Martin (referee) ; Jiřík, Radovan (advisor)
This bachelor thesis deals with quantification of perfusion using a contrast-free MRI technique called „Arterial Spin Labeling“ (ASL). Firstly, the physical principle of magnetic resonance imaging and the concept of perfusion will be described for better understanding of the subject. The next chapters will focus on the ASL method itself and perfusion quantification using mathematical models, namely T1 perfusion and Standard. The algorithm for preprocessing and analysis of selected datasets, designed in the thesis, is implemented using the program MATLAB. Program BASIL was used for further processing. The outputs in the form of perfusion and ATT maps and model fitting processes using various models from both programs are compared and evaluated.
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MRI of Rats - Quantification of T1 in Myocardium
Vitouš, Jiří ; Mézl, Martin (referee) ; Jiřík, Radovan (advisor)
This thesis focuses on cardiac imaging and quantification of T1 relaxation time in rat hearts. Its main focus is to investigate available methods for such quantification and their application in the development of quantification tools. The large impact is given to methods of acquisition synchronization, mainly with respect to cardiac motion and breathing using retrospective gating, where the navigator signal is obtained solely from the acquired data, so without any external equipment such as the ECG or respiratory sensors. This paper takes into account situations where steady-state has been reached and also those where it has not, by means of contrast agent injection or by inversion pulses.
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Quantitative properties of Banach spaces
Krulišová, Hana ; Kalenda, Ondřej (advisor)
The present thesis consists of four research papers. Each article deals with quan- tifications of certain properties of Banach spaces. The first paper is devoted to the Grothendieck property. The main result is that the space ∞ enjoys its quan- titative version. The second paper investigates quantifications of the Banach- Saks and the weak Banach-Saks property. The relationship of compact, weakly compact, Banach-Saks, and weak Banach-Saks sets is quantified, as well as some characterizatons of weak Banach-Saks sets. In the third article we discuss possible quantifications of Pelczy'nski's property (V), their characterizations and relations to quantitative versions of other properties of Banach spaces. The last paper is a continuation of the third one. We prove that C∗ -algebras have a quantita- tive version of the property (V), which generalizes one of the results obtained in the previous paper. Moreover, we establish a relationship between quantita- tive versions of the property (V) and the Grothendieck property in dual Banach spaces. 1
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Polyethylene wear particles around joint replacements - their properties, distribution and possible mechanism of their adverse biological effects
Zolotarevová, Eva
This PhD thesis in essence rounds off the range of queries asked several years ago when the task was set by Doc. RNDr. Zdenek Horak, PhD. The original isolation procedure for polyethylene wear particles, identification of some of their physico-chemical properties and manipulation accordingly has been successful in the process of this thesis accomplishment. It became possible to quantify the particles at relative as well as absolute scale. The thesis managed to disprove the published opinion that centrifugation can affect the morphology of isolated particles. The issue of distribution of polyethylene wear particles around hip endoprothesis has been solved at two levels: "macroscopically", the distribution of wear particles in zones around endoprosthesis was showed (this thesis does not include these data). Furthermore, at the "microscopic" level, the distribution of wear particles in granuloma tissue from the zones surrounding endoprostheses with most particles has been determined. The granuloma tissue formed in zones with most particles because of that. It was observed that the common term - osteoagressive granuloma - used by orthopedist is rather misguided. Granuloma is not aggressive to bone tissue. On the contrary, the granuloma formation reduces the effective amount of wear particles with...
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Quantification of procalcitonin in human serum by affinity surfaces and mass spectrometry
Dvořák, Josef ; Pompach, Petr (advisor) ; Kozlík, Petr (referee)
Sepsis is a worldwide health condition. It is caused by disproportionatly large immunity system response for patogene presence. Fast and accurate diagnosis of sepsis can make difference between life and death. For clinical diagnosis of sepsis is used serum protein procalcitonin (PCT) as biomarker. Procalcitonin concentration level in patient bloodstream increases up to thousand times in short time period. Severity of sepsis can be determined by correlation with its concentration in bloodstream. To determine PCT level in patient bloodstream a broad variety of specialized instrument is used. All methods have same principle of measurement - PCT-antibody interaction. Procalcitonin level is then quantified by calibration curve method. During these measurements non-specific protein-antibody interactions can occur and distort the quantification of PCT level. Mass spectrometry due to its properties comes into consideration as an alternative method, that can be used for PCT determination. Aim of this diploma thesis was in situ enrichment of PCT on surface modified affinity carriers with immobilized antibody against PCT. These carriers are compatible with matrix assisted laser desorption/ionization time of flight mass spectrometry. Mass spectrometry provides mass spectrum, where PCT and other signals...
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Vliv mírného teplotního stresu na expresi genů metabolismu cytokininů a kinetiku růstu klíčních rostlin Arabidopsis thaliana
Truong, Thanh Huong
Climate change and thermal stress poses a problem for sustainable agriculture. Research in the adaptation and acclimation of plants to the elevated temperature is therefore one of the current scientific issues. Plants are exposed to different ambient temperatures during their life. The response to adverse temperatures includes a number of signalling pathways affecting development and growth processes in plants. Coordination of develomental processes under elevated temperature and other external factors is primarily controlled by plant hormones. Here effect of cytokinins on plant morphology, growth kinetics, gene expression and quanification in combination with increased temperature was observed. By determination of the hypocotyl growth during increased temperature, cytokinins were found to play important role in this process. Cytokinins were found to inhibit temperature induced hypocotyl growth and inversly seedlings treated with higher temperatutre showed decreased level of cytokinins which was confirmed on the level of marker gene expression and determination of levels of cytokinins.
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Studium exprese genů v živočišných tkáních metodou real-time PCR
Valentová, Šárka
The gene expression study in animal tissues enables a better understanding of animal physiology which allows to control and regulate gene expression. Quantitative real-time PCR is a highly flexible method for studying gene expression. Several variants of the technology are currently available considering the chemistry and instrumentation used. Optimal results of gene expression studies require a clear understanding of this method and an overview of available variants. The bachelor thesis describes the real-time PCR method and its variants for their subsequent comparison in terms of suitability for different types of analysis and summarizes the main importance of gene expression studies in biotechnology and clinical practice. In addition, the sensitivity and the performance of the 7500 Real-Time PCR SYSTEM and Rotor-Gene Q instruments are compared. The mean values of measured Ct values have been compared by statistical t-test. The results conclude that there is no statistically significant sensitivity or performance difference between tested instruments.
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Advanced Methods of Perfusion Analysis in MRI
Macíček, Ondřej ; Frollo, Ivan (referee) ; Mikl, Michal (referee) ; Jiřík, Radovan (advisor)
This dissertation deals with quantitative perfusion analysis of MRI contrast-enhanced image time sequences. It focuses on two so far separately used methods -- Dynamic contrast-enhanced MRI (DCE-MRI) and Dynamic susceptibility contrast MRI (DSC-MRI). The common problem of such perfusion analyses is the unreliability of perfusion parameters estimation. This penalizes usage of these unique techniques on a regular basis. The presented methods are intended to improve these drawbacks, especially the problems with quantification in DSC in case of contrast agent extravasation and instability of the deconvolution process in DCE using advanced pharmacokinetic models. There are a few approaches in literature combining DCE and DSC to estimate new parameters of the examined tissue, namely the relaxivity of the vascular and of the interstitial space. Originally, in this scheme, the 2CXM DCE model was used. Here various models for DCE analysis are tested keeping in mind the DCE-DSC combination. The ATH model was found to perform better in this setting compared to 2CXM. Finally, the ATH model was used in alternating DCE-DSC optimization algorithm and then in a truly fully simultaneous DCE-DSC. The processing was tested using simulated and in-vivo data. According to the results, the proposed simultaneous algorithm performs better in comparison with sequential DCE-DSC, unleashing full potential of perfusion analysis using MRI.
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Quantitative analysis of matrix elements using SIMS and LEIS methods
Staněk, Jan ; Šik, Ondřej (referee) ; Bábor, Petr (advisor)
This thesis studies comparison and connection of two spectrometric methods – low energy ion scattering spektrometry (LEIS) and secondary ion mass spectrometry (SIMS). SIMS method, despite its many positive qualities, suffers of so called matrix effect, which makes quantifiaction of data very difficult. LEIS method on the other hand is immune to this effect and so it’s suitable completion of SIMS method. As a convenient sample have been chosen AlGaN samples with various concentration of gallium and aluminium. In the first part of thesis is introduced physical essence of SIMS and LEIS method, experimental details and studied samples. In second part of the thesis there’s a description of measurements and comparison of data gained by each method.
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