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Vlastnosti a regulace objemově-závislých aniontových kanálů u astrocytů.
Harantová, Lenka ; Anděrová, Miroslava (advisor) ; Moravec, Jan (referee)
Animal cells need to preserve constant volume in the face of osmolarity perturbations to function properly. To regain their original volume after hyposmotically induced swelling, most cell types extrude intracellular electrolytes and organic osmolytes accompanied by osmotically driven water. This process is termed regulatory volume decrease and is ensured by various ion channels and transporters. Recently, much attention has been focused on the ubiquitous volume-regulated anion channels activated by cell swelling. VRACs are moderately outwardly rectifying with intermediary conductance, permeable to inorganic anions and organic osmolytes and sensitive to broad-spectrum anion channels blockers. Functional properties of VRACs in astrocytes are particularly interesting, because many brain pathologies, such as ischemia, traumatic brain injury or hyponatremia, are associated with marked astrocytic swelling and VRACs could thus constitute a possible target for therapy of cerebral edema. Furthermore, VRACs are thought to play a role in cell cycle progression, cell migration, apoptosis and intercellular communication. Despite intensive research, VRACs molecular identity and mechanism of their activation and regulation are still unclear. This work summarizes known facts about VRACs, accentuating their...
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Neurosteroid modulation of ligand-gated ion-channel activity
Krausová, Barbora ; Vyklický, Ladislav (advisor) ; Moravec, Jan (referee)
The term neurosteroids refers to steroids that are synthetized in the nervous tissue from cholesterol or steroidal precursors from peripheral sources. These compounds affect the neuronal excitability by modulating the function of some ligand-gated ion channels. NMDA (N methyl D aspartate) receptors are glutamate gated ion channels involved in excitatory synaptic transmission, synaptic plasticity and excitotoxicity. GABAA ( aminobutyric acid type A) receptors mediate most of the inhibitory synaptic transmission in the mammalian brain and are targeted by many clinically important drugs. Function of NMDA and GABAA receptors can by affected by neurosteroids, both positively and negatively. The aim of this work is to summarize the current knowledge about the neurosteroid effects on the function of GABAA a NMDA receptors and suggest the physiological role and the potential therapeutic use of the neurosteroids as a regulator of some functions of the central nervous system.
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Phenotypic and molecular approaches in the systematics of the Palearctic and Neotropic tree frogs, Hyla and Osteocephalus (Amphibia: Hylidae)
Gvoždík, Václav ; Moravec, Jiří (advisor) ; Mikulíček, Peter (referee) ; Hulva, Pavel (referee)
The systematics and taxonomy of tree frogs of the family Hylidae has undergone turbulent changes both at higher (subfamilies, genera) and lower (species) level during the last decades. The original approach used morphological characters to distinguish tree frogs. It has been completed by bioacoustics, since the advertisement calls of the males were in some cases found to represent an important behavioural reproductive barrier and therefore useful for systematic evaluations. However, a completely new impulse was given to systematics by the introduction of modern genetic methods. These methods have allowed to distinguish not only morphologically but even acoustically cryptic taxa. The most reliable method to distinguish tree frogs at present is a combination of data from the different disciplines. The present dissertation thesis aims to evaluate the systematics of tree frogs of the genus Hyla from Eastern Europe and the Middle East as well as the systematics of the Amazonian genus Osteocephalus using a combination of morphological, bioacoustic and molecular approaches. The thesis is composed of a general introduction, three published papers, two manuscripts under reviews and a conclusion chapter. The first three papers deal with the phenotypic (morphological plus bioacustic) approach in systematic...
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Point processes on linear networks
Moravec, Jan ; Prokešová, Michaela (advisor) ; Pawlas, Zbyněk (referee)
The central theme of this thesis is the theory of point processes on linear net- works, in particular two kinds of the network K-function. The first part is devoted to the theory of stationary point processes in the plane, including the K-function and its estimator. The second part is concerned with the theory of point proces- ses on linear networks. There is defined the Okabe-Yamada network K -function and its estimator, the geometrically corrected network K-function, including its estimator, and there are explained their theoretical properties. In the third part we examine the ability of these two kinds of the network K-function to detect clustering or regularity in point processes on linear networks. There is explained the envelope test, the refined envelope test and the deviation tests. The software environment R with library spatstat is used for simulations.
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Combining classifiers by means of fuzzy methods
Moravec, Jaroslav ; Holeňa, Martin (advisor) ; Eckhardt, Alan (referee)
In this paper we elaborate a method of combining classifiers by means of the tconorm integral for SVM classifiers ensembles. We compare accuracy of combined classifiers for the case of SVM classifiers and quazi-Sugeno integrals. For t-conorm systems for integration, which we use to determine quazi-Sugeno integrals, we use t-norms from three families of t-norms, Aczél-Alsina family, Dombi family and Frank family. Results of our experiments show that combining classifiers by Sugeno integral is superior to integrals relying on the other considered t-norms.
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Ecology,ethology and variability of european green lizard Lacerta viridis in Natural reservation Tiché údolí
Chmelař, Jan ; Rehák, Ivan (advisor) ; Moravec, Jiří (referee)
The european green lizard, Lacerta viridis is a critically endangered reptile species which is in the region of Bohemia present only in relict isolated populations. These populations are closely linked to slopes with a southern exposition in deeply engorged river valleys. These valleys exhibit a unique climatic effect also known as the river phenomenon which allows numerous animal and plant species to survive far beyond their standard northern range. The chosen locality in Tiché údolí is a subject to long-term conservational management and the studied lizard population seems to reflect its effectiveness. This study is aimed to evaluate variability, ecological and ethological characteristics of lizards within the locality and is focused on changes on the population level. Key words: European green lizard, Lacerta viridis, Tiché údolí, river phenomenon, variability, ecology, ethology, population characteristics Abstrakt Ještěrka zelená, Lacerta viridis, je kriticky ohrožený druh plaza, který se na území Čech vyskytuje pouze v reliktních a izolovaných populacích. Ty jsou úzce spjaty se svahy v hluboko zaříznutých říčních údolích. Tato údolí vykazují unikátní klimatický efekt, známý též jako říční fenomén, který umožňuje výskyt četných živočišných i rostlinných druhů i za severní hranicí jejich běžného...
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Induction of neurogenesis and gliogenesis after ischemic injury of CNS
Filipová, Marcela ; Anděrová, Miroslava (advisor) ; Moravec, Jan (referee)
Ischemic injury (stroke) is one of the most common causes of death and disability in humans. Discovery of adult neurogenesis and possibilities to induce neurogenesis by cytokines brought new approaches and hopes in treating the ischemic lesion in future. The aim of this thesis is to describe cellular and molecular mechanisms of neurogenesis, mainly those discovered within last ten years. The first part describes generation of new neurons in the brain under physiological conditions, which is localized in the dentate gyrus of the hippocampus and in the subventricular zone of the lateral ventricles (i.e. in principal neurogenic regions). The second part describes animal models used for studying ischemic injury in rodents and moreover, it focuses on patophysiology of ischemic brain injury, which is accompanied by astrocyte and microglia activation. Further, the ischemia-induced neurogenesis is described in these two major neurogenic regions. Also the important role of NG2 glial cells in central nervous system (CNS) regeneration is pointed out. According to recent findings NG2 glia that are present in all regions of CNS might serve as a potential source of cells for directed differentiation into oligodendrocytes, astrocytes and even neurons during CNS repair/regeneration. In the last part of this work,...
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The role of synaptic modulation in pain states.
Adámek, Pavel ; Paleček, Jiří (advisor) ; Moravec, Jan (referee)
Everybody has experienced pain. Pain by definition is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. In the peripheral tissues acute painful stimuli activate specialized endings of afferent neurons called nociceptors. The information about tissue damage is then transmitted to the cell bodies of these dorsal root ganglion neurons by unmyelinated or thinly myelinated axons (C and A fibers, respectively). The central branches of these neurons form synapses with superficial dorsal horn neurons in the spinal cord. The information is conveyed at the synaptic connections by neurotransmitters such as glutamate and many others neuromodulators. Important is the subsequent activation of projection neurons that transmit the information to supraspinal brain areas. Activity of excitatory and inhibitory interneurons, glial cells and descending pathways from the CNS are also important for the modulation of nociceptive information at the spinal cord level. After peripheral tissue damage and in other pathological states, increased sensitivity to peripheral stimuli may develop. As results of this change innocuous stimuli are perceived as painful (alodynia) and increased pain is perceived after noxious stimuli (hyperalgesia). The underlying mechanisms of these changes may be...
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Ethical Plausibility of Suicide
Moravec, Jan ; Hogenová, Anna (advisor) ; Blažková, Miloslava (referee)
Diploma thesis "the ethical plausibility of suicide" deals with problem of suicide from philosophical and ethical spectacle. Enthrones essential metodological determination in view on different suicides. Importanat determination is essential enthronement of hierarchy of human questioning for life. In the thesis is showed primary onthological question, secondary qualitative question and tertiary quantitative wuestion. This determination of essential questions should help in inquiry for main thesis question: "in which cases is suicide ethicaly accetable or ethicaly good." Diploma thesis works with different arguments and admitances to suicide. Diploma thesis confrontates this arguments and admitances with offered metodology and with ethical norms and systems from onther philosophers. Those norms and systems are converted to essental three questions and consenquently compared, if they can predicate something about ethical acceptability suicide. Diploma thesis don't only stays on person of self-murderer. Diploma thesis tries to shows a connections between the act of suicide and relations with other people. The moment which draws together different cogitations is moment of toleration. Final admittance is build on teaching of John Locke. Diploma thesis is also forced to consider the problem of human freedom.
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