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Haematopoiesis in Sea lamprey
Kovář, Martin ; Bartůněk, Petr (advisor) ; Živný, Jan (referee)
To find out if the haematopoietic system is common feature of vertebrates, we decided to examine haematopoiesis in a sea lamprey (Petromyzon marinus). All blood cells arises from the haematopoietic stem cells in higher vertebrates. We assume that this is common for the higher vertebrates and a jawless vertebrates, but nobody was interested in the jawless haematopoiesis since 1970. Using a reverse genetic, we identify homologues of important hematopoietic of higher vertebrates in transcriptome of the sea lamprey with emphasis on important receptors or transcription factors, because they can be used as the specific markers of different blood cells and their progenitors. Then we use those sequences for cloning, expression measurements and other work. We picked up sea lamprey as model organism because its unique phylogenetic position, important foe evo-devo studies, but also because lack of elementary knowledge about sea lamprey haematopoiesis. Key words: Petromyzon marinus, haematopoiesis, HSC, evo-devo
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The mechanisms and regulation of lineage commitment in hematopoietic stem cell
Tichý, Marko ; Stopka, Tomáš (advisor) ; Svoboda, Ondřej (referee)
Hematopoietic stem cells (HSCs) are crucial for maintaining balanced homeostasis in the human body. HSCs are pluripotent cells, which are able to give rise to many very different cells. HSCs can be found in fetal liver initially during organismal development where they expand and move to their more definitive location, the bone marrow, shortly before birth in humans and mice. HSCs possess to not only recapitulate themselves (self-renew) or proliferate and expand, but are also the first branching point from which subsequent multipotent progenitors and eventually all blood cell lineages are formed thus establishing specific and restricted terminal differentiation pathways. The irreversible decision to initiate and follow a specific differentiation pathway is designated as lineage commitment. The drivers of lineage commitment, which are a base of this thesis, are intrinsic as well as extrinsic factors acting within the stem cell niche, such as transcription factors, chromatin remodeling factors, and cytokines, which are essential for proliferation, survival, self-renewal and lineage commitment decisions. These regulatory factors, working either independently or in mutual coordination, maintain balanced homeostasis of HSC renewal and their differentiation. The goal of this thesis will be to ascribe the...
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Comparing results of cell blood count and leukocyte differential count between different series of analyzers Sysmex
Opletalová, Monika ; Blažková, Hana (advisor) ; Bártů, Iva (referee)
In this bachelor thesis I focused on comparing results of cell blood count and leukocyte differential count between three types of Sysmex analyzers. XS - 1000 i, XT - 4000i and XE - 5000 are automatic analyzers, measuring on principles of flow cytometry and impedance methods using hydrodynamic focusation. These methods provide very accurate blood cell an alysis. The theoretical part of bachelor thesis is focused on description of hematopoesis, options for measuring cell blood counts and leukocyte differential counts and general description of measuring methods used by Sysmex analysers. In the experimental part I described the composition of mentioned analysers, their measuring channels and reagents which are used for peripheral blood cells analysis. Every sample from 50 patients was measured on each analyser and results were statistically compared by using ANOVA test. Graphs showing average values of each parameter for negative and positive patient ́s samples were made. The aim of this study was to summarize the main advantages and disadvantages of all three analyzers and determine whether differences in the results of samples between analyzers are statistically significant or not. Powered by TCPDF (www.tcpdf.org)
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Transplantace kostní dřeně příjemcům s regenerující krvetvorbou: účinnost transplantace a stav regenerující kostní dřeně
Forgáčová, Katarína ; Nečas, Emanuel (advisor) ; Vávrová, Jiřina (referee) ; Hofer, Michal (referee)
Hematopoietic stem cells (HSCs) have the ability of both self-renewal and differentiation. After bone marrow damage, surviving host HSCs or transplanted donor HSCs are able to restore hematopoiesis and maintain it for a long time due to the self-renewal potential. HSCs reside in a specific microenvironment in the bone marrow, in stem cell niche, which supports their survival and controls their functioning. In this study, we investigated the impact of bone marrow damage induced by increasing doses of irradiation on engraftment efficiency of transplanted donor repopulating cells. Using the CD45.1/CD45.2 congenic mouse model, we developed a new approach enabling estimation of surviving HSCs in damaged hematopoietic tissue. Its principle is in measuring of the donor chimerism resulting from transplantation of a defined dose of normal congenic bone marrow cells. The transplanted donor cells contain repopulating cells, progenitors (STRCs) and HSCs (LTRCs) that give rise to blood cell production which proceeds in parallel with that present in the host hematopoietic tissue. We applied this approach to monitor spontaneous regeneration of repopulating cells, including HSCs, in mice irradiated with a sublethal dose of 6 Gy or by a lethal dose of 9 Gy and rescued by syngenic bone marrow cells. This was...
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The role of microRNAs in lymphomas with a focus on miR-155
Hušková, Hana ; Stopka, Tomáš (advisor) ; Svoboda, Petr (referee)
MicroRNAs (miRNAs) are 19-25 nucleotide noncoding RNAs which regulate the expression of target mRNAs at both posttranscriptional and translational level. The physiological functions of miRNAs include development, differentiation, cell cycle regulation and apoptosis. miRNA deregulation has been found in various human diseases, including lymphoproliferative disorders. This Bachelor thesis provides introduction to delineate roles of miRNAs in normal hematopoiesis and cites recent publications on miRNAs in lymphomas with a focus on the role of miR-155. Key words microRNA, hematopoiesis, lymphoma, miR-155
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Origins of vertebrate hematiopoiesis
Svoboda, Ondřej ; Bartůněk, Petr (advisor) ; Divoký, Vladimír (referee) ; Živný, Jan (referee)
(ENGLISH) Hematopoiesis is dependent on the actions of hematopoietic stem cells (HSCs). This process is tightly controlled through a complex array of extrinsic and intrinsic factors. Even though the hematopoiesis seems to be well conserved across the disparate vertebrate animals, erythroid and thrombocytic differentiation have changed during the evolution of mammals. Specifically, adult mammalian red blood cells have the unique feature of being enucleated, and mammalian thrombocytes are not individual cells, but fragments of megakaryocytes, instead. It is likely that these enhancements provided a survival advantage to early mammalian species; however, they also bring up the question of evolutionary origin of these cells that studied using zebrafish (Danio rerio) model. First, it was necessary to generate a toolbox of a recombinant cytokines and optimized culture media that allowed us to manipulate zebrafish hematopoietic cells ex vivo in liquid and clonal cultures. Interestingly, teleost species underwent an extra duplication event during their evolution and as a result, two copies (paralogs) of some of the genes are present in zebrafish. This was also the case for majority of the cytokines from our toolbox and here, we provide functional characterization of these paralogs. Strikingly, our results...
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