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Endocrine disrupting compounds in the environment
Ezechiáš, Martin ; Cajthaml, Tomáš (advisor) ; Kočí, Vladimír (referee) ; Bláha, Luděk (referee)
A great variety of chemical compounds are released into the environment on a daily basis. Some of these compounds might be dangerous for human health or wildlife and might persist in the environment. In recent years, there has been a growing interest regarding chemical substances which could interfere with hormone biosynthesis and metabolism, cause a deviation from normal homeostatic control or negatively influence reproductive system. These chemicals are called endocrine disruptors. This dissertation thesis studied novel brominated flame retardants and selected pharmaceutical drugs as potential endocrine disruptors, based on their effect on hormonal receptors. Assays for estrogenic activities were also used for the evaluation of biodegradation experiments and for the validation of a novel mathematical model that could predict the effects of a mixture of toxic compounds. The results indicated that some of the tested chemicals were able to inhibit hormonal response of estradiol and testosterone and act as an anti-estrogens or anti-androgens. In the case of biodegradation experiments, the measured estrogenic activities were in agreement with the analytical concentrations of applied estrogens. Suggested mathematical model for mixture toxicity yielded a good fit with the experimental data from...
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Measurement and toxicity of combustion generated nanoparticles
Sikorová, Jitka ; Topinka, Jan (advisor) ; Klusoň, Petr (referee) ; Bláha, Luděk (referee)
This thesis is focused on nanoparticles produced by internal combustion engines utilized in vehicles. It deals with spatial distribution of nanoparticles within urban areas, impact of alternative fuels usage on particle production and toxicity, and a particle toxicological testing methodology. Monitoring of airborne nanoparticles identified traffic as the main source of airborne nanoparticles in places with heavy traffic load (Prague), as well as in a small city with only local traffic (Čelákovice). Most particles were likely emitted during short episodes of high emissions (e.g. uphill acceleration). During the measurements, high-emission vehicles responsible for a large fraction of the air pollution were also identified. On the other hand, small non-road internal combustion engines, which are not subject to any limit on particle emissions, such as a lawn mower, were operated during the measurement and generated a large number of nanoparticles. The amount and characteristics of the particles produced by combustion depend on the combustion technology and the fuel composition. A large part of the thesis deals with alternative fuels and their effects on the quantity of produced particles and toxicity of organic matter adsorbed on the particles. Hydrotreated vegetable oil (HVO) exhibited the lowest...
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The use of "omics" methods in molecular-epidemiologic study in newborns from different localities of the Czech Republic
Hoňková, Kateřina ; Rössner, Pavel (advisor) ; Gábelová, Alena (referee) ; Bláha, Luděk (referee)
The "omics" is a concept of biological disciplines that globally characterizes and quantifies biomolecules involved in the key functions of an organism. The "omics" methods are used e.g. in molecular epidemiology, where they help to evaluate potential biomarkers that identify the impact of environmental factors for human health. In this thesis, the "omics" methods were applied in samples collected from newborns born in localities of the Czech Republic mostly differing by pollution levels from industrial sources. The principal aim was to determine whether environmental changes during prenatal development can affect gene expression and its regulation in newborns. The thesis further aimed to evaluate the level of air pollution at the time of biological samples collection. Using the whole genome approach, differentially expressed genes (DEGs) in newborns from districts Karvina and Ceske Budejovice (CB) were identified. In a pilot study of a small group of newborns from districts Most and CB, differentially methylated CpG sites in DNA were assessed. These sites attenuate gene activity and could be responsible for long-term changes at the genetic level. Finally, the aim was to find differentially expressed small non-coding RNA (DE miRNA) in newborns from Most and CB. Samples of umbilical cord blood from...
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Measurement and toxicity of combustion generated nanoparticles
Sikorová, Jitka ; Topinka, Jan (advisor) ; Klusoň, Petr (referee) ; Bláha, Luděk (referee)
This thesis is focused on nanoparticles produced by internal combustion engines utilized in vehicles. It deals with spatial distribution of nanoparticles within urban areas, impact of alternative fuels usage on particle production and toxicity, and a particle toxicological testing methodology. Monitoring of airborne nanoparticles identified traffic as the main source of airborne nanoparticles in places with heavy traffic load (Prague), as well as in a small city with only local traffic (Čelákovice). Most particles were likely emitted during short episodes of high emissions (e.g. uphill acceleration). During the measurements, high-emission vehicles responsible for a large fraction of the air pollution were also identified. On the other hand, small non-road internal combustion engines, which are not subject to any limit on particle emissions, such as a lawn mower, were operated during the measurement and generated a large number of nanoparticles. The amount and characteristics of the particles produced by combustion depend on the combustion technology and the fuel composition. A large part of the thesis deals with alternative fuels and their effects on the quantity of produced particles and toxicity of organic matter adsorbed on the particles. Hydrotreated vegetable oil (HVO) exhibited the lowest...
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Endocrine disrupting compounds in the environment
Ezechiáš, Martin ; Cajthaml, Tomáš (advisor) ; Kočí, Vladimír (referee) ; Bláha, Luděk (referee)
A great variety of chemical compounds are released into the environment on a daily basis. Some of these compounds might be dangerous for human health or wildlife and might persist in the environment. In recent years, there has been a growing interest regarding chemical substances which could interfere with hormone biosynthesis and metabolism, cause a deviation from normal homeostatic control or negatively influence reproductive system. These chemicals are called endocrine disruptors. This dissertation thesis studied novel brominated flame retardants and selected pharmaceutical drugs as potential endocrine disruptors, based on their effect on hormonal receptors. Assays for estrogenic activities were also used for the evaluation of biodegradation experiments and for the validation of a novel mathematical model that could predict the effects of a mixture of toxic compounds. The results indicated that some of the tested chemicals were able to inhibit hormonal response of estradiol and testosterone and act as an anti-estrogens or anti-androgens. In the case of biodegradation experiments, the measured estrogenic activities were in agreement with the analytical concentrations of applied estrogens. Suggested mathematical model for mixture toxicity yielded a good fit with the experimental data from...
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Monitoring of toxic cyanobacteria in drinking water reservoirs in the C.R. (1993-2008) - traditional and new cyanotoxins
Maršálek, Blahoslav ; Bláha, Luděk ; Bláhová, Lucie ; Kohoutek, Jiří ; Adamovský, O. ; Babica, Pavel ; Šejnohová, Lenka ; Kopp, Radovan ; Vinklárková, Darina ; Maršálková, Eliška
Summary of results from the long-term monitoring of toxic cyanobacteria with special attention to drinking water supplies.
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