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The effect of partial agonist of serotonin-1A receptor on cognitive functions in animal model of schizophrenia
Antošová, Eliška ; Valeš, Karel (advisor) ; Telenský, Petr (referee)
Serotoin is a neurotransmitter participating in regulation of many physiologic fuctions. Main serotogenous neurons can be found in nukleus raphe of the brain stem. Nucleus raphe inervates many areas of the brain including the cerebal cortex and hipocampus. These structures are important for controling of higher cognitive functions. 5HT1A receptor is one of many subtypes of serotonin receptors and its activation inhibits iniciating of the action potencials. 5HT1A receptor is expressed presynapticaly as an autorecpetor in nucleus raphe. Activation of 5HT1A receptors decreased the output of the serotonin in the target structures. This key position enables to regulate the serotonin level in the brain. 5HT1A receptor can be found also postsynapticaly as an heteroreceptor in the hippocampus and in the brain cortex, where it affects the output of many other neurotransmitters. Experimental studies indicate that affecting of the 5HT1A function can improve many neuropsychiatric disorders such as schizophrenia, anxiety, depresion and it can also moderate the congitive deficit. It is supposed that the activation of 5HT1A autoreceptors and the inhibition of 5HT1A heteroreceptors can positively affect the cognigtive abilities. It seems that 5TH1A autoreceptors are more sensible for pharmacologic influence. Thus in these...
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Dual role of CD9 protein in mast cell activation
Machyna, Martin ; Dráber, Petr (advisor) ; Černý, Jan (referee)
Mast cells are well known effector cells in immune system. They have been implicated in such important processes as host defense against bacteria, toxins or parasites. However, in some cases they can develop improper reaction against harmless environmental antigens and thus causing allergies. It is therefore essential to understand signaling events that lead to activation of these cells in order to develop new treatment strategies. Newly prepared rat monoclonal antibody of IgG1 subtype raised against murine mast cells was characterized and found suitable for flow cytometry, immunoblotting and immunoprecipitation. Employing of optimized procedure for immunopurification in combination with mass spectrometry led to identification of its target cluster of differentiation (CD)9 protein. CD9 is a member of large protein family called tetraspanins. Functional studies showed that binding of this antibody to mast cells induced degranulation and early activation events such as increased tyrosine phosphorylation and enhanced levels of free cytoplasmic calcium. Interestingly, subsequent activation of these cells via antigen-mediated aggregation of the high-affinity IgE receptor (FcεRI) led to decreased degranulation, calcium response and tyrosine phosphorylation of several substrates. Importantly, anti-CD9 antibody did...
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The effect of the mast cell activation on the microtubule organisation
Hájková, Zuzana ; Dráber, Pavel (advisor) ; Binarová, Pavla (referee)
The activation of bone marrow-derived mast cells (BMMCs) induces a number of cell processes such as degranulation, proliferation and cytoskeleton rearrangements. Although microtubules are important in these processes, molecular mechanisms that control changes in microtubule organisation during cell activation are unknown. Activation of BMMCs can be achieved in several ways. Under physiological conditions, the aggregation of IgE receptors (FcRI) on the surface of BMMCs leads to the initiation of specific signaling pathways. Cells can be also activated nonspecifically by a tyrosine phosphatase inhibitor pervanadate, or by thapsigargin that inhibits Ca2+ ATPase pumps located on the endoplasmic reticulum. In this diploma thesis it was found out that rapid morphological changes can be monitored when BMMC are immobilised on the fibronectin before their activation. It was proved that specific and nonspecific activation events lead to microtubule reorganization, as well as to generation of a large number of microtubule-dependent protrusions. In the course of FcRI aggregation, generation of microtubule protrusions depends on the activity of Src family protein tyrosine kinases and on the intracellular Ca2+ concentration. STIM1, an endoplasmic reticulum Ca2+ sensor, which participates in the activation of...
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Study of mechanism of action of anticancer drug tamoxifen and its toxic side effects
Kylarová, Salome ; Stiborová, Marie (advisor) ; Moserová, Michaela (referee)
Anti-estrogen therapy is used for treatment of hormone (estrogen) receptor positive breast cancer. The rise of this type of cancer is associated with a prolonged exposure to these hormones throughout life. Tamoxifen is one of the most used hormonal drugs, which blocks the effects of these hormones in breast cancer tissue by competitive binding to hormonal receptors. The affinity of tamoxifen to these receptors is not sufficient, therefore it has to be activated to metabolites having greater affinity, namely 4-hydroxytamoxifen and endoxifen. The formation of these intermediates is catalysed by cytochromes P450. In the second phase of its biotransformation hydroxylated metabolites of tamoxifen are primarily sulphated by sulphotransferases and eliminated from the body. In addition to these active intermediates, which inhibit the growth of breast tumor tissue, there are metabolites causing negative effects in the others. The most important metabolite is α-hydroxytamoxifen, which forms covalent DNA adducts in liver tissue of rats and endometrium of females. Tamoxifen therapy is associated with numerous side effects, but the greatest attention is focused to formation of endometrial cancer and induction of tumor's resistance to this therapy. Effects of tamoxifen therapy are dependent on the activity of...
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název v anglickém jazyce není uveden
Kolesová, Hana ; Grim, Miloš (advisor) ; Slípka, Jaroslav (referee) ; Nečas, Emanuel (referee)
Branchial arches region and its blood vessels are extensively transformed in the embryonic development. Aim of this study is to investigate mechanisms of the branchial arches region development and to study how a morphogen Sonic hed gehog (Shh) participate on the formation and remodeling of branchial arches and their blood vessels. Influence of Shh was evaluated based on the changes caused by its inhibition in vivo. Shh function was inhibited with an anti-Shh antibody, which was produced into the embryo from the applied hybridoma cells. Shh signaling cascade was also inhibited by cyclopamine. Results show that Shh is important for dc novo format,ion of the blood vessels in the branchial arches region. Further Shh is necessary for stabilization of the vessel wall, mainly for anterior cardinal vein. Shh also alfects later vessel development and transformation, which includes i.e. fusion of the dorsal aorta, branching of the internal carotid artery and outflow tract development. Short time inhibition of Shh has minor effect on the apoptosis and proliferation activity of the branchial arches region mesenchymal cells. We assume that Shh signals directly to the blood vessels endothelial cells, as Shh receptor ptel is also expressed in endothelial cells and its signal is reduced with Shh inhibition. In studied...
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Cytotoxicity of new taxol derivatives in selected tumor cell lines
Némethová, Ingrid ; Skálová, Lenka (advisor) ; Kvasničková, Eva (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Ingrid Némethová Supervisor: Doc. RNDr. Lenka Skálová, Ph.D. Title of diploma thesis: Cytotoxicity of new taxol derivatives in selected tumor cell lines. Paclitaxel (Taxol, PTX) is a natural product with antitumor activity, used in the treatment of various types of solid tumors, especially breast and ovarian cancer. It belongs to the so-called mitotic poisons, which cause cell cycle arrest and apoptosis of cells by interference with microtubule dynamics. The aim of this study was to compare the antiproliferative effect of PTX and its derivatives, prepared in the ÚEB AVČR by conjugation of peptide receptor agonists for gonadotropin-releasing hormone (GnRH) within a targeted cancer therapy. For the experiment was chosen cell line MCF-7, which is derived from breast adenocarcinoma and has receptors for GnRH. The results were evaluated by two different methods (NRU, MTT). Of the six tested substances showed derivative MP 265 the most significant antiproliferative effect. When using the other substances occurred more pronounced decrease in cell-life at higher concentrations compared to PTX.
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Preemptive analgesia & the role of drugs affecting nervous system in potentiatio n of analgesics efficacy
Slíva, Jiří ; Kršiak, Miloslav (advisor) ; Geršl, Vladimír (referee) ; Kozák, Jiří (referee)
The aim of our research is was to determine whether new and already clinically successfullyused anticonvulsant levetiracetam has a preemptive or therapeutic effects in the model of postoperative pain in rats. The second objective of our research was to determine whether guaifenesin increases the efficiency even analgesic NSAIDs, with different selectivity for COX-2 (ibuprofen, nimesulide and celecoxib) in the model of visceral pain in mice. As Previously, it was discovered that guaifenesin increases theabsorption of paracetamol, we investigated whether guaifenesin also affect plasma levels of one of the NSAIDs tested, andnimesulide. The third main objective of our research was therefore to determine whether cannabinoid receptor agonist CP-55940 increases the analgesic activity of diclofenac in amodel of visceral pain model in mice and inflammatory pain in rat.
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The effect of Goeckerman therapy on selected markers of angiogenesis and inflammation in psoriasis patients
Pohl, David ; Andrýs, Ctirad (advisor) ; Hernychová, Lenka (referee) ; Petrisková, Jela (referee)
Psoriasis is one of the most common skin diseases affecting about 2-3% of the caucasian population. Its clinical presentation is the formation of red scaled plaques on the skin. The main pathological features of psoriatic plaque comprise of skin inflammation, disturbances of keratinocyte proliferation and maturation and angiogenesis. Although the precise precipitating mechanism of psoriasis has not been discovered yet, the key element in psoriasis initiation is T- lymphocyte population. Nevertheless, other inflammatory cells (e.g. neutrophils, macrophages) as well as activated endothelium play a role in its pathogenesis. Indeed, one of the first histological changes in the affected skin is leukocyte infiltration. The so called trafficking of inflammatory cells to the skin is tightly regulated process guided by cytokines especially chemokines. Angiogenesis is a process of new blood vessel growth from preexisted vessel bed. Vessels in the most of the tissues of adult individual remain in a state of quiescence. The rate of endothelial cell turnover is relatively slow (1-2 years). However in cases of physiological or pathological requirements, a new vessel formation can be initiated by the mechanism called angiogenic switch. One of the pathological conditions associated with angiogenesis is formation of...
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Studies on NKR-P1A and NKR-P1B receptors expressed in eukaryotic organisms
Ivanova, Lyubina ; Rychlovský, Petr (referee) ; Bezouška, Karel (advisor)
NK (natural killer) cells, with their ability to identify antigens and extraneous substances, available in the organism through various moleculary receptors, are an important component of the immune system. The NKR-P1A and NKR-P1B proteins belong to the lectin receptors of natural killer cells. Primary ligands of lectin receptors comprise terminal oligosaccharides of glycoproteins on the surface of target (e.g. tumor) cells. The interaction between carbohydrate structures on the surface of antigens and their binding partners on NK receptors is followed by triggering the effector function of NK cells against the targets. The NK cells and NK receptors findings and their interactions with ligands are greatly utilized in the treatment of cancer, viral and autoimmune diseases. Heterologous protein production in the eukaryotic organism brings a lot of advantages. Unlike the prokaryotic organism, the methylotrophic yeast Pichia pastoris has the capability of performing many posttranslational modifications resulting in production of biological active protein molecule. Usually, the P. pastoris expression system disposes of high level protein expression and is also generally regarded as being faster, easier, and less expensive to use than expression systems derived from other eukaryotes. In this thesis, I...
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