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Ambient ozon impact on vegetation
Bystrianský, Martin ; Hůnová, Iva (advisor) ; Čabala, Radomír (referee)
Bystrianský: Ambient ozone impact on vegetation - Abstract Ambient ozone is present in the air all around the world. It is natural component of the atmosphere, due to anthropogenic emissions of ozone precursors its concentration rise. That is unlikely, because ozone is toxic. Ozone is formed as a part of photochemical smog from ozone precursors by photochemical reactions. As ozone precursors nitrogen oxides (NOx) and volatile organic compounds (VOC) are called. Their main source is car traffic. Danger of ozone lies in its reactivity. It oxidizes most of organic compounds, especially those containing double bonds. These are present in membrane lipids. Furthermore, ozone forms more reactive compounds than itself - active oxygen species (AOS), free radicals. Ozone effects negatively both human health and vegetation. Ozone disrupts structure of the cells, which for plants means destroy of leaves and needles, photosynthesis disruption and biomass loss. For that, plants have antioxidants system for AOS scavenging. But it has little effect, when concentration of ozone is high during smog period. Therefore, limits for maximal concentration of ozone in the ambient air are set.
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Oxidative stress as the possible outcome of opioid treatment
Böhmová, Barbora ; Novotný, Jiří (advisor) ; Žurmanová, Jitka (referee)
Free radicals and reactive oxygen species are continuously formed in all aerobic organisms. They may be implicated in ethiology of some diseases such as cancer, atherosclerosis, rheumatoid arthritis, liver, renal, cardiovascular, and neurodegenerative diseases and premature aging. Free radicals and reactive oxygen species can also cause oxidative damage to important cellular components - proteins, lipids, and DNA. Cells are equipped with antioxidant systems to neutralize these radicals. The antioxidant system includes some vitamins (ascorbic acid, α-tocopherol, β-carotene) and enzymes, e.g., superoxide dismutase converting superoxide radical to hydrogen peroxide and molecular oxygen or catalase destroying H2O2. Another important H2O2-removing enzyme in human cells is glutathione peroxidase. Reduced activity of antioxidants leads to excessive production of free radicals resulting in oxidative stress. Opioids belong among pro-oxidants (chemicals inducting oxidative stress). Opioids can decrease activity of antioxidant enzymes and generate reactive oxygen species. The aim of this bachelor thesis is to gather information regarding the opioid ability to elicit oxidative stress. It briefly summarizes our current knowledge about opioids, oxidative stress, free radicals and antioxidants. Key words Opioids,...
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Effect of iron overload on the induction of apoptosis in mammalian cells
Kabíčková, Tereza ; Balušíková, Kamila (advisor) ; Klíma, Martin (referee)
Iron cations are an important metal ions required to number of essential cell functions. On the other hand, ferrous iron can be very toxic as well. When surplus iron is present in cells, it can catalyze the formation of reactive oxygen species (especially hydroxyl radicals) by Fenton reaction. Iron homeostasis is predominantly regulated by very strict mechanisms on the level of iron uptake into the body. Moreover, iron absorption, transport and storage within the body can be also regulated using complex mechanisms which differ on the level of individual cells and on the level of whole organism. Deregulation of iron homeostasis causing an iron overload and generation of reactive oxygen radicals can evoke serious cell damage leading up to apoptotic cell death. Excess iron storage and subsequent development of oxidative stress can affect lot of different tissues in the body. The organ damages such as fibrosis, cirrhosis, hepatocellular carcinoma, heart failure, loss of β cells and glucose intolerance or diabetes mellitus in patients with iron overload are very often seen. Nevertheless, the apoptosis induced by iron overload has not been well elucidated yet. There are no complex informations about the precise mechanism by which oxidative stress affects different cell types or whether there are other...
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Mitochondrial production of reactive oxygen species and its role in physiological regulations
Holzerová, Eliška ; Mráček, Tomáš (advisor) ; Kalous, Martin (referee)
The production of mitochondrial reactive oxygen species and the resulting oxidative stress is an important phenomenon driving long-lasting research and intense discussions. Knowledge of exact mechanisms of reactive oxygen species production and pathways leading to their formation could help us to directly affect their production, a task with potential terapeutic implications. The molecular nature of the production of reactive oxygen species by some enzymes has already been well documented, but others still remain controversial and current theories are obviously far from the truth. Much more interesting is the question of physiological importace of this production. The reactive oxygen species were considered harmful factors clearly distorting the integrity of the organism for a long time. However, recent research suggest that their existence can also be beneficial and effective. Evidently they can serve as a signaling molecules in several metabolic and regulatory pathways occurring in the organism. This bachelor thesis offers insight into the current state of knowledge. It focuses on the most detailed description of the reactive oxygen species production by mitochondrial respiratory chain enzymes. Furthermore, it deals with some signaling cascades, where involvement of mitochondrially generated...
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The influence of oxidative stress on mammalian sperm quality and fertilization ability.
Dudková, Barbora ; Komrsková, Kateřina (advisor) ; Svoboda, Petr (referee)
This bachelor's thesis deals with the oxidative stress and its influence on structures and physiologic functions of mammalian sperm. Oxidative stress is a consequence of imbalance between pro-oxidants and anti-oxidants in the body. It is associated with impaired quality of sperm and it is considered to be one of the major reasons of male infertility, including humans. This work is presented as a research review targeting how and where reactive oxygen species are generated in the male reproductive tract. It summarizes specific structures and physiologic functions that are influenced by reactive oxygen species either positively or negatively and it also covers a protective role of antioxidants in seminal fluid.
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Surface ozone as a factor of oxidative stress in mountain forests.
Bendáková, Hana ; Hůnová, Iva (advisor) ; Matoušková, Leona (referee)
This study presents mountain forest Norway spruce (Picea abies) injured by surface ozone and oxidative stress. Norway spruce is not a sensitive species but it is the most representative tree in our country and this is the reason to pay attention on its injury. Study was connected to the ozone measurement by CHMI in Jizerske mountains. Aim of our study was to find influence of surface ozone on the forest and show correlation between ozone concentrations, altitude and Norway spruce injury. Ozone concentrations are growing with the altitude. Increasing percentage of injury with growing concentrations and altitude was expected. Needles were collected at the altitude 750-1100 meters. Collected needle years were 2006, 2007 and 2009. The 2009 year was not evaluated because no symptoms were found. Injury was observed on the maroscopical, microscopical and biochemical level. Visual injury was assessed by percentage of injured needle surface by chlorosis and necrosis. Microscopical analysis studied injury on cross and longitudinal sections of needles. On the longitudinal sections were visible typically bone-cells. These cells have lost its shape by ozone stress and were narrowed in its width. Bone-cells were best visible near the stomata. Four symptoms were observed on the cross sections: tannin...
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Gilbetr syndrome
Šimáková, Eva ; Kuklík, Miloslav (advisor) ; Kučerová, Mária (referee)
The mail focus of this thesis is to assess a genealogical frequency of homo- and heterozygotes for a mutation in a promotor region of UGT 1A1 gene. This mutation is typical for Gilbert's syndrome. It explains a genesis, symptoms, pathology and also a therapy of this syndrome. It discusses a possibly protective effect of this polymorphic mutation that might result in a lower incidence of vascular diseases (myocardial infarction, stroke, atherosclerosis, pulmonary embolism). An important contribution is also an attenuation of stress due to hyperbilirubinaemia. This thesis was worked out in a cooperation with GENVIA Ltd.
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The molecular mechanism of CSL protein participation in oxidative stress response in Schizosaccharomyces pombe
Daněk, Petr ; Převorovský, Martin (advisor) ; Sipiczki, Matthias (referee)
Redox homeostasis maintenance is important for proper organism and cell function, for while relatively low amount of reactive oxygen (and nitrogen) species contributes to the fine tuning of signal transduction, excessive concentration of ROS (oxidative stress) has demonstrably harmful effects and is tightly connected to many pathological states. Cells therefore evolved broad palette of antioxidant mechanisms that express striking level of conservation among different species. Large, intricate stress response signaling networks have been already described; nonetheless, novel molecules employed in stress-related signaling are still being discovered. Several studies recently suggested transcription factors CSL, proteins essential for regulation of metazoan development as effectors of Notch signaling, are also involved in response to oxidative stress. The fission yeast Schizosaccharomyces pombe, well established model of response to various stresses, comprises two paralogs of CSL proteins - Cbf11 and Cbf12. We have found cells depleted of cbf11 are highly resistant to hydrogen peroxide. This resistance appears to be caused by upregulation of important stress responsive genes including ctt1, gst2, pyp2, and atf1. Cbf11 is therefore negative regulator of these genes, which suppresses their expression...
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Vliv chronicky podávaných subletálních dávek parakvatu na délku telomer a rezistenci vůči oxidačnímu stresu drozofily
TOMÁŠKOVÁ, Jindřiška
As the most widely dispersed fauna around the world, insects are exposed to a range of stresses within their environments. Oxidative stress causes a disturbance of the balance between production of free radicals and antioxidant response, which leads to various physiological changes in an organism. Despite this, there are several of defense mechanisms, which include in particular the main antioxidant enzymes AKH. In this thesis, I tried to contribute especially to understand the physiological nature of telomere elongation after exposure to free radicals.
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Antioxidanty v bylinných čajích
Musilová, Eva
This bachelor's thesis "Antioxidants in Herbal Teas" brings a summary of substances with antioxidant properties contained in herbs used for production of herbal teas. The basic terms, e.g. oxidative stress, antioxidant, or free radical, are explained first. The individual groups of plant antioxidants (flavonoids, phenolic acids, terpenoids, chlorophylls etc.) are described in terms of their chemical structure and occurrence. There is also a brief introduction to methods for determining antioxidant activity (DPPH, TEAC, FRAP etc.). The next section focuses on the parts of plants used for production of herbal teas, tea preparation methods and characterization of selected herbs concerning their components with antioxidant effects. The final part of the thesis deals with the importance of antioxidants for human health in relation to particular diseases (cancer, cardiovascular and neurodegenerative diseases etc.).
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