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The mechanisms of specific polutants impact on aquatic communities.
Vaněčková, Hana ; Fuksa, Josef (advisor) ; Hořická, Zuzana (referee)
With a decrease of classic pollution of water ecosystems the importance of PPCP (pharmaceutics and personal care products) increases. Their amount is increasing due to human consumption and thus the input into municipal wastewater and consequently into the surface water, eventually into the ground water increases as well. This bachelor work is a review of scientific literature in the field of PPCP water load. The goal is resuming the results of the studies of the influence of these substances on freshwater aquatic communities. In the beginning the sources of the variability (in time and space) of the concentrations of these substances in rivers are resumed. But the rate of affection of the aquatic communities depends even on the length of exposure, which is longterm with regard to the continuous flow of substances from wastewater treatment plants. That is why the effect of long-term incidence on aquatic communities is intensively studied. The emphasis is put on the incidence of endocrine disruptors (substances disrupting the endocrine system), which affect e.g. the oestral cycle of some kind of exposed populations. There are observed changes in the way of perception of a predator by his prey whereas the escape reactions of the prey happen to be affected. The additive effect of ixtures of...
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Functional analysis of sperm quality after endocrine disruptor treatment
Linhartová, Zuzana ; Liberda, Jiří (advisor) ; Ryšlavá, Helena (referee)
The aim The aim of my study was to determine whether the selected endocrine disruptors (EDs) affect reproductive parameters of sperm. Due to two experimental models, in which was tested the influence of selected Eds, my work is divided into two parts: A) On the boar model (Sus scrofa) was tested effect of selected EDs (zearalenone (ZEN), di(2-ethylhexyl) phthalate (DEHP), vinclozolin (VIN) on the course of capacitation, acrosome responses in vitro and changes in the detection and localization of selected proteins. B) On the fish model (Perca fluviatilis L.) was tested the influence of the selected ED- bisphenol A (BPA) on the motility and velocity of fish sperm movement. Results Mammalian model In mammalian model the course of capacitation and acrosome reaction was significantly influencing by the examined EDs in comparision with control samples. The increase of the number of marked cells during capacitation and reduce of the number of marked cells after AR compared with the differences between experimental and control samples was confirmed by the flow cytometry method. At higher concentrations EDs clearly inhibited acrosome response and thus reduce the number of sperm capable of fertilization. The relevancy of the results of detection acrosome reaction was confirmed by using various methodological...
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Influence of estrogens on mammalian sperm.
Šidlová, Adéla ; Šebková, Nataša (referee) ; Hortová, Kateřina (advisor)
For many years, estrogens have been considered typically female sex hormones. It is now certain that they are also very important in the regulation of male reproduction, whether their effect is positive or negative. Endogenous estrogens in mammalian males are an important part of the endocrine system. Estrogens play an important role in the growth and maintenance of bone mass, as well as in the development of germ cells and in the marches of spermatogenesis. Healthy sperm are essential for successful reproduction. Effect of endogenous estrogens is partly involved in the regulation of proper development of sperm. Besides the positive effect of endogenous estrogens, there is also a negative effect of estrogens from the external environment, so-called environmental estrogens. Between environmental estrogens are man-made chemicals, xenoestrogens, which increasingly contaminate the environment. Hazards of these estrogenic substances in nature is hidden in their ability to act as endocrine disruptors, which cause defects in many aspects of mammalian reproduction. With regards to the fact that there are more and more substances in current environment that can interfere with hormonal path of mammalian reproduction, it is important to look at this issue. Reproductive disorders that may be caused by...
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Ecotoxicity tests on cellular level
Procházková, Petra ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Endocrine disrupting compounds among significant environmental pollutants. They are dangerous both for humans and other organisms by affect their hormonal system. They enter the environment during production, use and disposal some chemicals, but they may be of natural origin. The aim of this work is to give a brief overview of possible methods of determination of the presence of ecotoxic substances in the environment, using the in vitro toxicity assays. These tests use cell cultures instead of test organisms. The work describes principles of ecotoxicity tests at the cellular level, such as cell viability assays, cell proliferation assays, assays based on the metabolic activity of cells or DNA microarrays. A significant part of this work is focused on the possibilities of determination of endocrine disruptors by selected assays. They are ligand binding assays, reporter gene assays (recombinant yeast assay, mammalian-based reporter gene assays) and cell proliferation assay called E-screen. Significance and rationale use of tests to prove the endocrine activities in environmental matrice is given through examples of studies in which the tests were used.
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Aplication of Photocatalytic Processes for Contaminated Water Cleaning
Maléterová, Ywetta ; Krejčíková, Simona ; Spáčilová, Lucie ; Cajthaml, Tomáš ; Kaštánek, František ; Šolcová, Olga
The necessity of finding the alternative solutions for environmental protection leads to development and use of the new technologies. Photo-catalysis has been applied as a promising technique for the wastewater decontamination and/or purification using semiconductor particles have found increasing interest to solve the resistant pollutants remove problems. This study is focused on verification of the specially designed photoactive materials and their modified versions suitable for photo-processes carried out upon illumination in the UV light.TiO2 as a photocatalyst immobilized in thin layers on glass beads or glass tubes were used for the degradation of 4-chlorophenol and endocrine disruptors namely 4-nonylphenol, 17-ethynylestradiol and bisphenol A in water solution with allowance of the toxicity of final water. Experiments demonstrate the efficiency of photocatalytic degradation for all compounds in both types of photocatalytic reactor (batch and continual arrangement) was 85% in average. The toxicity and the estrogenity of final water were monitored. The long term efficiency of titania catalyst was also proved.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22013103010060 - PDF
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