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Application of passive sampling for the analysis of hormones in drinking water
Remerová, Martina ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
The thesis focuses on the use of passive sampling during an analysis of hormones in drinkable water. In the theoretical part there are described selected passive samplers and the sample of the type of POCIS is described at fuller length. The next chapter engages with steroid hormones and an input of estrogenic hormone into the environment. The thesis contains chapters dealing with possibilities of the determination of hormones in water. It is specialized on the analysis of drinkable and surface water. In the last chapter of the theoretical part there are introduced water works where samples for an experimental assessment were collected from. The experimental part of the thesis presents the specification of the extraction of analytes and an adjustment of used device. In the thesis there are specific calibrations for individual assessment of hormones. The results of the assessment for each collection point are ordered to a well-arranged table. Increased levels of targeted estrogens were not approved in most of sampling points.
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Methods of water samples processing with subsequent in vitro detection of endocrine disrupters
Daniel, Romain Oliver ; Komendová, Renata (referee) ; Bittner,, Michal (advisor)
In recent years, interest in monitoring of estrogenic compounds in water environment due to their adverse effects on human and animal health has been increased. Partiucular attention is paid to analytical techniques used to quantify estrogens in water samples, such as instrumental and biological techniques (in vitro, in vivo). Water samples need to be concentrated due to very low estrogen levels (ng·L-1) and low limit of detection of used analytical methods. Solid phase extraction (SPE) or liquid-liquid extraction (LLE) are comonly used to concentrate water samples. This bachelor thesis represents reverse osmosis (RO) and nanofiltration (NF) as another possible methods for this purpose. This thesis is focused on the preconcentration of water samples spiked with four estrogens (estrone E1, 17-estradiol E2, estriol E3 and 17-ethynylestradiol EE2) and surface water samples taken from three watercourses in city of Brno using RO and SPE and its comparison of their effeciency. This was evaluated by in vitro estrogenicity assay on the stably transfected cell line hER-HeLa-9903. By using RO, estrogens were concentrated with different recovery – the highest recovery was reached for EE2 129.29%, lowest for E2 38.53%. No detectable amount of estrogen has been detected in surface water samples. RO appears to be a suitable method to the water samples preconcentration prior to in vitro analysis of endocrine disrupting compounds. Water samples treated by the SPE method were not measured untill the sunbmission of bachelor thesis, so the RO and SPE efficiency was not performed.
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Hormones and their presence in environmental
Sučková, Tereza ; Dvořáková, Petra (referee) ; Vávrová, Milada (advisor)
This thesis deals with the issue of hormones in the environment and analytical methods for the determination of hormonal substances in water and soil ecosystems. The thesis includes an overview of important hormone groups (divided into categories according to their chemical structure) and basic information about properties of chosen hormones, their sources and impacts on the environment. The next focuses upon methods of determination of hormones in soil and water ecosystems. Finally, a standard operational manual for analysis of estrogens in surface water has been created and is provided herein.
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Mathematic Modelling of Reverse Osmosis System Design for Detection of Estrogens in Water
Siegel, Jan ; Skopalík, Josef (referee) ; Bittner, Michal (advisor)
Estrogen compounds are a subgroup of the environmental pollutants named Endocrine Disrupting Chemicals. It is a large group of chemicals which are capable of causing hormonal imbalance of an organism and affecting its reproductive, developmental or behavioral functions. In the environment, they are found in very low concentrations (below ng/l). This makes their detection and elimination highly problematic. The Research Centre for Toxic Compounds in the Environment (RECETOX) has been developing an experimental device which employes reverse osmosis (RO) to concentrate the trace amounts of micropollutants (e.g. estrogens). The aim is to lower the detection limit of subsequent analytical methods. RO seems to be a promising alternative to commonly used methods which are more time consuming and costly. The aim of this thesis is to create a mathematical model of RO, which would describe the process of estrogen concentration and therefore could contribute to the optimization of experimental device. The mathematical model was created in MATLAB-simulink and verified by comparison to thirteen experimental results. The solutions used to test the model were NaCl at 0.002–2 g/l and drinking water with 17-ethinylestradiol of 25 ng/l. In order to concentrate the retentate on a flat-sheet RO membrane the model achieves a mean relative error in the range of 0.9–4.9 % for NaCl and drinking water. For the concentration of estrogens the deflection is 3.6 %. Comparing the model and experimental concentration of NaCl on a spiral wound RO-membrane, the deviation is in the range of 5.9–8.7 %. So far, ratio of retentate volume from the beginning to the end of the process has been used to determine the process recovery. However, due to the results obtained in the thesis, this approach appears inaccurate. A more accurate recovery would likely be achieved by using the theoretical concentration value obtained by the proposed mathematical model. However, to increase reliability, the further measurements with estrogens are needed, and also to determine the causes of deflection of model and experimental retentate volume values at the end of the concentration
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Study of Pharmaceuticals Degradationby Advanced Oxidation Processes
Bílková, Zuzana ; Čáslavský, Josef (referee) ; Beklová, Miroslava (referee) ; Zachariášová,, Milena (referee) ; Vávrová, Milada (advisor)
At present, the issue of occurrence of female sex hormones, estrogens and progestogens, in aquatic ecosystems is often discussed by experts and the general public. These substances of steroid structure can be difficult to remove completely by conventional wastewater and drinking water treatment technologies. In given context advanced oxidation processes based on in situ generation of highly reactive hydroxyl radicals can be a suitable technique. This thesis deals with the study of kinetics and degradation products of photocatalytic decomposition of seven female sex hormones (estrone, -estradiol, estriol, ethinylestradiol, diethylstilbestrol, progesterone and norethindrone). Experiments were conducted in a laboratory glass reactor, which was equipped with an energy efficient UV-A LED light source (365 nm emission wavelength) and an immobilised photocatalyst in a form of TiO2 five-layer film deposited on glass. Model samples of water with the initial hormone concentration of 1 mg·L-1 were used and the degradation process was monitored by an HPLC-MS method. In the given system all compounds of interest except estriol had very significant tendency to be adsorb. In the case of estriol the formal rate constant of photocatalytic decomposition was determined based on the Langmuir-Hinshelwood model for two different initial concentrations, 0.5527 hour-1 (1 mg·L-1) and 0.1929 hour-1 (5 mg·L-1), and by comparison of these values it was found that the higher degraded compound concentration, the slower decomposition (fivefold increase of the initial concentration resulted in the constant decrease to almost one-third). Moreover nine degradation products of estriol photocatalytic decomposition were recorded and their structure was designed based on mass spectra. In the second thematic part of the thesis attention was paid to development of a SPE-HPLC-MS method for simultaneous determination of female sex hormones in water ecosystems, with emphasis on an extraction part optimization. The final samples treatment process included besides extraction with Supel™ Select HLB 200 mg SPE cartridges also mechanical impurities removal, hormones extraction from solids trapped on filtration material, sample acidification and extract purification with Supelclean™ ENVI-Florisil® cartridges. Optimised method was used for determination of female sex hormones in two Brno rivers, Svitava and Svratka. In the most cases the concentration was below the detection or quantification limit.
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Determination of hormones in wastewater
Zouharová, Kamila ; Tulková, Tereza (referee) ; Vávrová, Milada (advisor)
The presented theoretical and practical study was focused on a single unit of drugs – hormones. In the present study were characterized in detail hormones as drugs or medical ressource and their mode of effect on the human body. Another important part of this study was focused on the evaluate of the incidence of estrogens in the environment and their possible impact on the aquatic ecosystem, mainly for waste water. The last part of study was processed analytical problems of determination of hormones. There were introduced pre-analytical and analytical methods – methods of isolation of hormones from the waste water and methods of thein final determination, which were based mainly on the separation processes.
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Effect of estrogens on in vitro models of testicular tissue and spermatogenesis
Jursová, Pavlína ; Děd, Lukáš (advisor) ; Tlapáková, Tereza (referee)
Although estrogens are primarily known for their functions in female reproductive system, their effect on male reproductive functions has also been well established. Physiological estrogen concentration is essential for a proper spermatogenesis. Estrogens regulate many functions in testicular tissue, including proliferation and apoptosis of all testicular cell types, dynamic restructuring of cell-cell junctions in the testis, and post-translation modifications of histones. Hence, the aim of this thesis was to study effect of estrogens on in vitro models of testicular tissue and spermatogenesis and thus to address their functions in testicular tissue more deeply. This project includes testicular organoid cultivation for further usage as in vitro model of spermatogenesis. To addresss the effect of various avaliable estrogen forms, experiments on MCF-7 cell line were done. Finally experiments with in vitro model of testicullar tissue - TM4 Sertoli cell line were done. In order to fulfill the aims and verify the hypotheses, some advanced methods such as CLARITY volume confocal imaging and holographic microscopy were used. It was found that estrogens can affect Sertoli cell morphology and the expression of some genes involved in cell-cell junction dynamics. Furthermore the process of spermatogenesis was...
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Removal of organic pollution using advanced oxidation processes
Přibilová, Petra ; Kučerík, Jiří (referee) ; Chýlková, Jaromíra (referee) ; Opatřilová, Radka (advisor)
The presented doctoral thesis deals with the use of advanced oxidation processes combining hydrodynamic cavitation (HC) to produce hydroxyl and sulfur-based radicals. The investigated micropollutants are selected natural estrogens estrone (E1), 17-estradiol (E2), estriol (E3) and synthetic 17-ethinylestradiol (EE2). The theoretical section includes information on the properties of estrogens, their occurrence and effects in the environment on non-target organisms across trophic levels; and list of options for their removal from wastewater. The advanced oxidation processes themselves are also discussed and current knowledge in this area is summarised. In the research section, used analytical methods (LC-MS/MS and spectrophotometry), designs of individual experiments and results of tested processes are described. In addition monitoring the efficiency of different combinations of hydrodynamic cavitation and other agent and the suitability of the materials used on the experimental unit were also investigated. The sorption/desorption onto the surface of selected plastic materials (SBR, EPDM, PTFE, Tygon S3TM, PVDF and PVC) was also evaluated. Based on the results, the material for the unit - on which the degradation experiments were carried out - was selected. The methods chosen for the removal of estrogens from water were HC/H2 O2 , HC/O3, HC/percarbonate, HC/persulfate, hydrodynamic cavitation alone, and H2O2 alone. The design of the experiments was created to minimize the time required to treat the water, ideally one cycle per unit (4 seconds), which corresponds to the flow-through arrangement of the system.
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Historical development of the usage of contraception since the end of the 20th century to the present time
Bajerová, Michaela ; Černý, Andrej (advisor) ; Šimonová, Daniela (referee)
The bachelor thesis topic is "Historical development of the use of contraceptives from the end of the 20th century to the present day". It is divided into 2 parts - theoretical and practical. The theoretical part is devoted to the basic and extended division of contraceptives into hormonal and non-hormonal forms. After the basic division, we can find a table of contraceptive reliability. Furthermore, we will find the favourable, unfavourable effects and possible contraindications of hormonal and non-hormonal contraception. The history of each form is also briefly mentioned. In the practical part, I was interested in the different views of three generations of women and examined the historical development of demand for forms of contraception across their reproductive ages. I constructed a total of 3 questionnaires to better distinguish differences of opinion. I obtained responses from a total of 403 respondents in the categories of women born before 1979, between 1980-1989, and born after 1990 inclusive. The pre-constructed hypotheses helped me to evaluate each objective. For the second question, each respondent had to answer whether she had encountered contraceptives at least once; this allowed me to eliminate biased results, and thus only women who had encountered contraceptives more than once...
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Effect of prenatal hormonal levels on human sexual orientation
Freudenfeld, Petr ; Havlíček, Jan (advisor) ; Kubička, Lukáš (referee)
Sexual orientation is extensively studied topic nevertheless its etiology remains unclear. Several theories have been proposed to explain it. One of them is Neurohormonal theory of homosexuality. According to this theory, sexual orientation is affected by prenatal levels of androgen hormones. This thesis includes selected studies of experimental manipulations with prenatal levels of hormones in model mammalian species to explain effects of these hormones. Main part of the thesis focuses on the effect of prenatal androgens in humans using somatic biomarkers, for example 2D:4D digit ratio. Studies concerning sex, age and ethnic differences are described in detail. Great attention is dedicated to studies of sexual orientation. In women it seems that sexual orientation could be influenced by prenatal hormones, in men this theory isn't supported. This thesis summarizes and critically evaluates available literature concerning the effects of prenatal hormones on human sexual orientation.
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