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The role of NADPH oxidase and ros in invadopodia formation
Hanušová, Kristýna ; Brábek, Jan (advisor) ; Vrbacký, Marek (referee)
Invadopodia as specific organelles enabling tumour cells movement, spreading over the organism and ultimately formation of metastasis are possible and promising targets of tumour therapy. Recently, many interesting facts about assembly and mechanism of function of invadopodia were discovered. Invadopodia are centres of ECM degradation by extra-cellular proteases facilitating an invasion of tumour cells. For creation of invadopodia a precisely localized increased production of ROS is necessary. ROS work as crucial signalling molecules and participate in many processes resulting in invadopodia formation. ROS in tumour cells are produced by specific extra-mitochondrial NADPH oxidases (Nox). Several regulatory molecules participating in activation and localization of Nox to invadopodia have been discovered recently (Tks organizer proteins). Furthermore, a regulatory role of Src kinase in ROS production and subsequent invadopodia formation was confirmed. Key words: ECM degradation, invadopodia, invasion, proteases, Nox, ROS, Src kinase, Tks proteins
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Realist theories and the causes of the US invasion to Iraq
Klincová, Lucia ; Karlas, Jan (advisor) ; Rychnovská, Dagmar (referee)
The bachelor thesis called "The realist theories and the causes of the US invasion in Iraq" discusses the motivations that led the representatives of the United States of America to the decision to invade Iraq. These causes are analyzed based on the theoretical approaches of the offensive and defensive realism. We focus directly on the theories by which we create hypotheses suggestive of the possible causes which could have led the United States to this decision. Every hypothesis then takes into account the public debate of the presented causes. This thesis mainly focuses on the effort to gain the access to the Iraqi oil resources, the strengthening of the U.S. currency, the weakening of the dictatorial regime of Saddam Hussein and the tendency to eliminate the potential threats caused by the weapons of mass destruction. After defining the theories, taking into account the public debate and formulating the hypotheses, we are trying to confirm or refute them and thus highlight the real causes of the U.S. invasion of Iraq, which is the essential purpose of this bachelor thesis.
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Structure and function of the invasion apparatus of microsporidia
Dohnálek, Vít ; Doležal, Pavel (advisor) ; Vávra, Jiří (referee)
Microsporidia are obligate intracellular parasites that cause significant economic damage and can infect humans. They had evolved highly specialized invasion apparatus that is unique to them. During the invasion the sporoplasm is released from the spore wall and it is transferred to the host cytoplasm through the polar tube. Current research on the invasion apparatus has been focused mainly on the polar tube that is its most prominent structure. Polaroplast and posterior vacuole remain out of the main interest, although they are necessary for the activation and execution of the invasion. If the right combination of environmental factors occurs, the organization of the polaroplast begins to change, the posterior vacuole starts to swell and the polar tube is discharged. Sporoplasm is eventually pushed through the tube into the host cell by growing posterior vacuole. The mechanism has not been explained yet however plenty of theories are trying to explain the germination. This work summarizes current theories and knowledge of structure and function of particular parts of the invasion apparatus. Key words: Microsporidia, invasion, polar tube, intracellular parasitism, germination
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The role of dipeptidyl peptidase-IV and homologous proteases in migration and invasion.
Fejfarová, Edita ; Bušek, Petr (advisor) ; Rösel, Daniel (referee)
Migration and invasion are processes which naturally occur in organism during embryogenesis, immune reactions or wound healing. These processes are very important factors in some serious diseases like rheumatoid arthritis and carcinogenesis. There is no doubt about contribution of proteases in these processes-many of them degrade extracellular matrix and thereby facilitate the movement of cells. While dipeptidylpeptidase-IV cleaves solely two amino acids from N-terminus so it is not considerably involved in ECM degradation. DPPIV and its homologues recognize peptides with proline on penultimate position, which causes resistance to ordinary types of proteases. Substrates of DPPIV and its activity homologues include chemokines implicated in signalling of migration - their cleavage and thus inactivation present DPPIV and DPPIV-like molecules as modulators of cell migration signalling in choriocacinoma, neuroblastoma, on Sézary cells or epithelial cells migrating in response to injury. Another activity of some DPPIV-like proteases is binding to the extracellular matrix proteins, when are helping in the attachment of cells and thus affect the migratory ability of the cells like ovarian cancer cells, prostate cancer cells, melanoma cells or kidney cells. Effects on migration and invasion have also...
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Genetic structure of mammalian invasive populations on islands
Loudová, Miroslava ; Černá Bolfíková, Barbora (advisor) ; Hájková, Petra (referee)
Biological invasion is understood as introduction, establishment and expansion of organisms into new, non-native area. This is a natural process that is significantly compounded by human activities and is one of the factors that threaten biological diversity and stability of natural ecosystems. Understanding to the evolution and current status of invasive populations is especially important for planning a project to eradicate invasive species from certain areas to avoid their negative impact on the environment. One option for the research of the invasive populations and their history is the analysis of genetic material. This thesis summarizes the current knowledge on invasive populations of small mammals on the islands, with the focus on genetic studies. Specifically, the study of Norway rats (Rattus norvegicus) on Moturemu island and five archipelagos off the coast of Brittany; black rats (Rattus rattus) on Congo Cay, Madagascar, Guadeloupe Archipelago, Sainte Anne Archipelago and Canary Islands; Pacific rats (Rattus exulans) on Tetiaroa Atoll; house mice (Mus musculus) on Marion Island; house mice (Mus musculus domesticus) on Kerguelen Archipelago; red squirrels (Sciurus vulgaris) on Jersey island, West European hedgehogs (Erinaceus europaeus) in New Zealand; pygmy shrews (Sorex minutus) in Ireland and...
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The United States' policy of democracy promotion after the intervention in Iraq.
Klimešová, Tereza ; Hornát, Jan (advisor) ; Riegl, Martin (referee)
Bibliographic note KLIMEŠOVÁ, Tereza. The Implications of the Intervention in Iraq for the United States' Policy of Democracy Promotion. Master thesis. Charles University, Faculty of Social Sciences, Institute of International Studies, Supervisor Ph.Dr. Jan Hornát, Ph.D. Abstract Democracy promotion has been an integral part of US foreign policy for more than a century. Particularly at the end of the 20th century, democracy flourished worldwide as autocratic regimes collapsed at large and scholars talked about the "End of History." Nevertheless, the current situation is very different, and substantial democratic backsliding is observable. Many scholars are tracing the origins of this decline to the Bush's Freedom Agenda, particularly the intervention in Iraq in 2003, arguing that it was the initial turning point for US democracy promotion. However, this thesis argues that the invasion and the subsequent war were pivotal only in part. The most visible implications were within the public perception of democracy promotion. Due to the US engagement in Iraq, domestic support deteriorated substantially. Moreover, the international community's perception of the US as a benign democracy exporter crumbled as well. Another change was observable within the rhetoric of President Obama after taking office in 2009. In...
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Invasion of the host cell by the parasitic protist Plasmodium falciparum.
Charvátová, Klára ; Doležal, Pavel (advisor) ; Tůmová, Pavla (referee)
Plasmodium falciparum is an intracellular parasite that causes tropical malaria. Although plasmodium is not a problem in the middle latitudes, in tropical and subtropical regions it poses a great health threat. This specifically concerns little children, which constitute more than a half of the victims. This thesis discusses the invasion of the red blood cell by a merozoite, which is a key step of the parasite life cycle responsible for the disease development. The main part of the thesis deals with proteins secreted by organelles of the invasive apparatus of plasmodium cell. It is preceded by a chapter introducing basic information on P. falciparum and malaria. The end of the thesis contains a chapter on the parasite exit from the red blood cell. Key words Invasion, plasmodium, parasite, merozoite, red blood cell, tight junction, gliding motility, apical complex, micronemes, rhoptries
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Changes in the distribution of invasive neophytes in the riparan vegetation of the Berounka river
Randová, Nela ; Matějček, Tomáš (advisor) ; Lipský, Zdeněk (referee)
Riparian vegetation along the water courses is one of the places that are highly vulnerable to the spread of invasive alien plants. Water corridors allow their easy and rapid spread to new area. The diploma thesis occupies with changes in the distribution of the invasive neophytes in the riparian vegetation of the Berounka river during the years 2015-2018. The objective of this study was to find out how changes in the course of each year will be reflected and whether a certain trend of population development can be traced. In connection with this, the thesis occupies with the possible influence of extremely dry years 2015 and 2018 on the occurrence of invasive neophytes. Field research took place on the banks of the Berounka river from the village of Čilá near Skryje to the confluence of the Berounka and Vltava river in Prague-Lahovice during the summer months in 2015, 2016, 2017 and 2018. The riparian vegetation was divided into 500 ± 150 m long segments. There were 90 segments where the occurrence and abundance of 17 invasive neophytes were mapped. In total, occurrence of 14 taxons was registered. The most frequent taxons were Robinia pseudacacia, Impatiens glandulifera and Solidago sp. in the Berounka riverbank vegetation. The highest number of specimen was recorded for invasive neophyte...
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