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Real-time ECG monitoring
Valentová, Vanessa ; Mézl, Martin (referee) ; Šikner, Tomáš (advisor)
The key element of ECG signal analysis is the detection of the QRS complex. The QRS complex is the most significant part of the signal. In this work, there is a short summary of methods used for QRS detection in real time. Based on previous research, the detection alghorithm is chosen and created in LabVIEW. The paper is also focused on cardiac arrhytmias. Created alghorithm is used for detecion certain types of arrhytmia. Alghorithm was tested on MIT/BIH arrhytmia database.
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Laboratory diagnosis of disorders of phagocytosis
POLÍVKOVÁ, Ivona
Phagocytosis is one of the oldest processes of absorbing particles like amoeba, which is one of the basic mechanisms of the immune system to defend the body against infections. Failure of these processes is clinically manifested like immune deficiency and it can cause a very serious complication which could leads to the death of the patient. Phagocytosis is performed by specialized cells (macrophages, dendritic cells, neutrophils and other phagocytic myeloid cells) which are able to absorb the target particles, especially microorganisms, dead cells and foreign objects. These processes are essential for stability of homeostasis. Absorption of micro-organisms leads to activation of adaptive immunity response, elimination of apoptotic and destroyed cells and starts the reparation processes of damaged tissue. Phagocytosis as a complex process can be divided into several phases: active movement of phagocytes to the inflammation zone, adherence, ingestion and intracellular degradation which leads to the killing of pathogens. There are two mechanisms of killing pathogens. First is independent on oxygen where antimicrobial substances are stored in azurophilic granules which could be released into phagolysosom. Second mechanism is oxygen-dependent called oxidation (respiratory) flare which leads to the formation of biologically active mediators where oxygen molecules have considerable oxidation potential. Defects in phagocytic system are mainly caused by low number or malfunction of neutrophils which leads to severe infections mainly caused by staphylococci, Enterobacteriaceae or fungi. Among malfunctioning of phagocytosis processes belongs LAD I and LAD II syndrome. The other possible disorder of phagocytic malfunction is defect in enzymes. The NADPH oxidase is necessary for bacterial lyses mechanism of phagocytes and lack of these enzyme caused serious inherit disorder called chronic granulomatous disease. Lack or completely missing of enzyme myeloperoxidase stored in the azurophilic granules of neutrophils and monocytes is more and more common autosomal recessive disorder of phagocytosis. In this diploma work I focused on detection of these rare and serious disorders defects using flow cytometry to detect respiratory burst activity of neutrophils in blood samples. This laboratory procedure is called a burst test. In this test we quantitatively evaluate the respiratory burst activity of granulocytes in heparinized blood samples using the flow cytometery. Principle of this method is an oxidation-reduction reaction of dihydrorhodamine 123 to green fluorescent rhodamine 123 using peroxide, hydroxyl radicals and superoxide anions which are activated by respiratory burst. This process is one of the significant characteristic of phagocytic cells which are characterized by multi-stage activation of NADPH oxidase. This oxidase catalyzes electron reduction of molecular oxygen to superoxide. This step plays a very important role in our immune system and allows to kill and degrade particles and bacteria in phagocyte cells. Since 2009 - 2012 I analyzed the results of 611 patients who were tested for respiratory burst of neutrophils on a request of their physician. Among all of these results we obtain only two positive results of reduction of stimulation index (SI) and significant decrease percentage of activated granulocytes. Both of these parameters: reduced percentage of (activated granulocytes stimulated by PMA and E. coli) and low stimulation index pointing to a potentially serious disorder of phagocytosis mechanism. In specific tests of these cases proved the enzyme defect in phagocytosis mechanism which is the most common disorder in this type of immunodeficiency. These results indicate that the major primary defects of phagocytosis are very rare and their detection is usually in childhood for suspicion of primary immunodeficiency. This test is very helpful for discovering a prime immunodeficiency.
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Nanoparticles formed by complexes of copolymers with low-molar-mass compounds
Vojtová, Jana
This thesis is focused on mixed systems of various copolymers (double hydrophilic block and gradient polyelectrolytes, hydrophobic graft copolymers) and low-molar-mass compounds (sodium dodecyl sulfate as a representative of a ionic surfactant or superparamagnetic iron oxides in the form of nanocrystals). The electrostatic and hydrophobic interactions in the studied systems in aqueous solutions leading to aggregation behavior and to the formation of co-assembled nanoparticles were investigated by combination of scattering and microscopy techniques, including light, X-ray and neutron scattering, electron microscopy and atomic force microscopy. Powered by TCPDF (www.tcpdf.org)
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Mimetic complex of Central European red-and-black bugs (Heteroptera)
Hotová Svádová, Kateřina ; Exnerová, Alice (advisor) ; Žďárek, Jan (referee) ; Krištín, Anton (referee)
Aposematic animals signal to the predators their unprofitability (e.g. unpalatability, toxicity) Predators have either innate bias against warning signals or they have to learn to avoid aposematic prey. Aposematic species with similar warning signals profit from their resemblance and form mimetic complexes. Theoretically, there are five types of mimetic relations between species within the mimetic complex: Batesian, quasi-Batesian, quasi- Müllerian, Müllerian and super-Müllerian. Classification of mimetic relations depends on the level of mutual resemblance, and presence, type and efficiency of defensive mechanisms. Central European red-and-black true bugs (Heteroptera) were used as a model of mimetic complex in my Ph.D. thesis. We used six species of passerine birds. The species differ in body size, preferred food and reactions toward aposematic red-and-black prey and non- aposematic brown-painted prey. Although the diet of some passerine birds may include true bugs, there is evidence that birds mostly avoid aposematic species. In the first paper included in the thesis, we found that mimetic complexes may be predator dependent. There are differences in the extent of Batesian-Müllerian mimetic complexes and in the relations among the species involved. In the second paper, we analysed reactions of...
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The tools for study of cholesterol in biological membranes
Koukalová, Alena ; Nováková, Olga (referee) ; Černý, Jan (advisor)
Cholesterol is one of the major membrane component in most eukaryotic cells, where it performs multiple functions. Cholesterol regulates the fluidity of cell membranes, influences the activity of several membrane proteins and is the precursor of many steroid hormones and bile acids. Cholesterol is not a fluorophor or chromophor on its own, therefore it is necessary to visualize it to study its localization and distribution in cells. Reporter molecules that can be used for this purpose can be classified in two groups: specific cholesterol binding probes and cholesterol analogues. Among specific binding cholesterol probes are cholesterol oxidase enzyme that catalyses the reaction of cholesterol and oxygen into the products cholest-4-en-3-one and hydrogen peroxide and is used to study membrane organization and cholesterol flip-flop kinetics in plasma membrane, the polyene filipin forms fluorescent complex with cholesterol and is usually used to gain information about cholesterol distribution and localization in cells. Thiol-activated cytolysins and a derivate of perfringolysin O - BCθ-toxin - are suitable for recognizing cholesterol-rich domains and localization cholesterol in membrane. Cyclodextrins (especially methyl-β-cyclodextrin) selectively extract cholesterol from membranes and they can be used as...
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The Effect of EGF - like Peptides on Cumulus-Oocyte Complexes
Blaha, Milan ; Krylov, Vladimír (referee) ; Němcová, Lucie (advisor)
In mammals, the ovarian cycle is controlled by follicle-stimulating hormone (FSH) and luteinizing hormone (LH), secreted by the anterior lobe of the pituitary gland. FSH is assumed to be essential for follicle growth. LH is required for the terminal phases of follicle growth, estrogen synthesis, ovulation, development of the corpus luteum and progesterone synthesis. Although cumulus cells and oocytes lack LH-receptors, LH causes cumulus expansion and meiosis resumption. The effect of LH is mediated via EGF-like peptides - amphiregulin (AREG), epiregulin (EREG) and betacellulin (BTC). The precursors of these peptides are present in the mural granulosa cells and EGF-like peptides are released by activation of metalloproteases in response to LH-stimulus. The aim of this thesis is to present EGF-like peptides in the wide context of the molecular mechanisms regulating the late phases of folliculogenesis and meiotic maturation of oocytes.
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