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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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Determination of estrogen pollutants in real water sample by HPLC-UV after solid phase extraction.
Kozlík, Petr ; Bosáková, Zuzana (advisor) ; Coufal, Pavel (referee)
4 Abstract Estrogens are considered to belong to chemicals that negatively affect the endocrine system, even if present at very low concentrations. They are discharged into environment as a result of an increasing application of drugs etc. This work is focused on the separation and quantification of five estrogens, namely estrone (E1), 17β-estradiol (βE2), 17α-estradiol (αE2), 17α-ethynylestradiol (EE2) and estriol (E3) in natural water samples by HPLC-UV method. The chromatographic system consisted of a C18 stationary phase (SunFire® C18, 150 x 4.6 mm, octadecyl bounded to silica gel, particle size 5 µm) and binary mobile phase of acetonitrile/water in various ratios in isocratic separation mode. The effect of acetonitrile content in the mobile phase and flow rate of the mobile phase on retention and separation parameters was tested. Under the optimized separation conditions (acetonitrile/water 40/60 (v/v), 1.3 ml/min), all the compounds were baseline resolved and eluted within 15 min. These experimental conditions were applied to the calibration measurements which were carried out within the concentration range from 0.001 to 1 mg/ml. Limits of detection (LOD) and limits of quantification (LOQ) for the individual estrogens and their mixture (standards dissolved in methanol) were determinated. The detection...
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The effect of estrogens on capacitation and acrosome reaction of boar spermatozoa in vitro.
Dostálová, Pavla ; Pěknicová, Jana (advisor) ; Nedvídek, Josef (referee)
Fertilization is a unique biological event where male and female gametes fuse together to produce a new organism. Before the gametes are able to fuse, however, they must undergo a series of controlled changes. For the male gamete, capacitation and acrosome reaction (AR) must occur, which take place during the sperm migration through the female genital tract. Unfortunately, while the process of capacitation has been known for over half a century, the molecular basis and influential factors behind it are not fully understood. Although estrogens have been considered mainly female reproductive hormones, there is increasing evidence suggesting that these steroids have an important role also in regulation of male reproductive functions. Sperm come into the contact with estrogens during their formation in the male and female genital tract, indicating that the hormone may play an important role in sperm maturation. In this study, we examined the importance of three endogenous estrogens (E1 -estron, E2 - 17β estradiol, E3 - estriol) and one synthetic estrogen (EE2 - 17α ethinylestradiol) on sperm maturation during capacitation and AR. Stimulatory effect were observed with all tested estrogens on both capacitation and zona pellucida induced AR. Moreover, we have determinied that the stimulatory effect on...
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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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Causes currently increased incidence of thyroid carcinomas
Škarková, Barbora ; Brynychová, Iva (advisor) ; Dvořáková, Šárka (referee)
The thyroid carcinoma incidence has currently multiplied and the largest increase was recorded for thyroid papillary carcinoma. The aim of this work is to discuss factors increasing the risk of thyroid carcinoma. The only confirmed risk of developing this form of carcinoma is ionizing radiation mostly in connection with nuclear attacks and nuclear power plants disasters. Other risk factors include iodine intake and the influence of nitrates, both of which act as separate risk factors and also as factors increasing the risk potential of ionizing radiation. Thyroid carcinoma occur 3 times more frequently in women, therefore the risk factors specific for females, such as estrogens, assisted reproduction methods, pregnancy and hysterectomy, are also discussed. Hypothyroidism and Hashimoto's thyroiditis have a significant association with thyroid carcinomas while controversial factors are risky elements of lifestyle and nutrition (eg smoking, cruciferous vegetables, high glycemic index and body weigh index). A high incidence of thyroid carcinomas was found in volcanic areas in connection with the effects of heavy metals contained in lava. Another high incidence was recorded in the areas with low average annual temperatures. One of the reasons for the increase in the incidence of thyroid carcinoma is...
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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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The influence of estrogens on mouse sperm capacitation and acrosome reaction in vitro
Tejnická, Magda ; Komrsková, Kateřina (advisor) ; Linhart, Otomar (referee)
There are an increasing amount of compounds in the environment that can have a negative effect on reproductive parameters in both male and female organism. There has been a worldwide decline of sperm quality during past decades and this fact lead to an increase of unnatural ways of conception through assisted reproduction techniques in the specialised centres. Natural estrogens are one of these compounds and they get into waste water after being excluded from the body by the urine. They get back into the human body from drinking water or from the food, and they can interfere with function of endogenous hormones in very low concentrations. For these reasons it is up to date to deal with the influence of these compounds on mammalian sperm. 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. Endogenous estrogens in mammalian males are an important part of the endocrine system. Estrogens play an important role in the development of germ cells, spermatogenesis and processes leading to successful egg fertilization such as a capacitation or acrosomal reaction. Tyrosine phosphorylation is one of the essential steps for the properly ongoing process of capacitation in sperm followed by a...
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