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The role of the gastrointestinal hormones in the control of energy homeostasis
Myšáková, Michaela ; Horáková, Olga (advisor) ; Ergang, Peter (referee)
Zachování tělesné homeostázy vyžaduje precizní komunikaci mezi všemi buňkami organismu. Velkou měrou k tomu přispívají gastrointestinální hormony, které jsou významnými signálními molekulami a podílejí se na distribuci i zpracování přijatých živin. Každý h typem buněk a jeho sekrece je regulována v závislosti na přítomnosti konkrétních nutrientů. Vzhledem rozdílné anatomii jednotlivých částí gastrointestinálního traktu, je lokalizace buněk produkujících šná. Účinky gastrointestinálních hormonů jsou rozmanité a hrají důležitou roli energetické kontrole organismu. Některé hormony (gastrin) působí jen lokálně, naproti tomu jiné (inkretiny, ghrelin) jsou zapojeny do signalizace přes centrální i periferní ne do signalizace nervové soustavy umožňuje těmto hormonům podílet se na regulaci pocitu hladu a mnoha onemocněními. V důsledku nevyváženého příjmu živin (například při nadměrném příjmu lipidů nebo sacharidů) dochází narušení některé ze složek hormonálního regulačního systému a následně vzniku onemocnění. Nejznámějšími onemocněními, vzniklými v důsledku nutriční a následně hormonální dysbalance, jsou například inzulínová rezi hormony je naprosto klíčová pro zachování lipidového metabolismu i glukózové homeostázy. Klíčová slova:
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Seasonality of reproduction in tropical birds
Kačírek, Vojtěch ; Sedláček, Ondřej (advisor) ; Tomášek, Oldřich (referee)
The aim of of this paper is to summarize the knowledge of reproduction seasonality of tropical birds. Work includes characteristics of individual tropical environment and changes in abiotic conditions, focusing on the question, in what sense are tropics aseasonal and what is not. The work includes an overview of methodologies for collecting data during field research focused on monitoring reproduction in birds. The main part of this work is to compare the differences between biogeographic regions, regions and their stimuli, which most commonly lead to the creation of seasonal reproduction, followed by a comparison of individual functional groups of birds (food guilds). Powered by TCPDF (www.tcpdf.org)
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Anxiety disorders from a biological and psychological perspective
Záplatová, Klára ; Šivicová, Gabriela (advisor) ; Hrachovinová, Tamara (referee)
Barchelor thesis focuses on anxiety disorders from a biological and psychological perspective. This thesis aims to provide anxiety disorders in their entireness. For this reason, thesis focuses on psychological and physical symptoms of anxiety. Topic contains unconscious symptoms manifesting inside of a man. Thesis is divided into two main parts. First one consists of literature review, the second one consists of experiment design. Experiment design deals with physiological symptoms of social phobia. It is focused on specific brain areas and cortisol level in anxiety feeling as well as to feeling of a man during the experiment. Powered by TCPDF (www.tcpdf.org)
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Hormonal regulation of behavioral manipulation in insects caused by parasites
Janů, Hana ; Jůzová, Kateřina (advisor) ; Žďárek, Jan (referee)
Number of scientific publications describing how parasites alter their host's behaviour providing them successful reproduction or transmission to other hosts has significantly increased during the last few decades. In recent years, more and more researchers are not only describing changes in the host organisms, but also trying to figure out mechanisms beyond these parasitic manipulations. Parasites can manipulate the host through neural and endocrine system using neuromodulators, immunomodulators, neurotransmitters and hormones. Either increase or decrease of hormone levels may cause changes of the infected hosts development, metabolism, reproduction and behaviour. Hosts, whose behaviour is altered via hormonal pathways are mostly developmentally arrested and their feeding and locomotion is terminated. Observed behavioral changes like hole digging or termination of participation in group work in insects demonstrably increase parazite's fitness. This thesis is a summary of behavioral manipulations of insects caused by changes in hormone levels.
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Physiological aspects of the variability in eggshell pigmentation
Mengr, Jan ; Javůrková, Veronika (advisor) ; Krist, Miloš (referee)
The avian eggshell colouration is caused by specific pigments deposited into the eggshell. These pigments differ in colour, chemical structure and the eggshell deposition place. The function of the eggshell pigmentation is traditionally considered to have cryptic or thermoregulatory role. However, most recent hypotheses provide a new perspective on the function of eggshell pigmentation. As between species variability in the eggshell pigmentation is under strong genetic control, within species variability is considered to be a result of adaptation to environmental factors affecting physiology of female bird. This work focuses on the description and characteristics of particular eggshell pigments, their synthesis, deponation process and also the importance of variability in the avian eggshell pigmentation and its physiological aspects. Powered by TCPDF (www.tcpdf.org)
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The influence of thyroid hormones and adrenal glands on mental function
Augustinová, Jana ; Šivicová, Gabriela (advisor) ; Špinka, Marek (referee)
This thesis focuses on effects of thyroid and adrenal hormones on mental functions, especially on cognitive functions and emotions. In the case of adrenal hormones it will also focus on stress and burnout syndrome, which are not considered as mental functions, but are connected to both psyche and the above mentioned hormones. The text is divided into two parts. The first, theoretical part deals with the anatomy and histology of these two organs, hormones that they produce and their influence on overall physical condition and pathology. The main section of this theoretical part deals with the description of influence of thyroid hormones and adrenal glands on the above mentioned mental functions. This work is based on both earlier and contemporary research, but predominantly on foreign research. In the second, empirical part, a proposal for longitudinal study of cortisol and thyroxine levels during depression treatment is presented. Klíčová slova: Hormones, thyroid glang, adrenal gland, mental functions, cognitive functions, emotions, stress, cortisol, thyroxine
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Biological aspects of stress
Sarisová, Kristina ; Šivicová, Gabriela (advisor) ; Hrachovinová, Tamara (referee)
The aim of this thesis is to describe stress as a psychological phenomenon with an emphasis on the biological aspects. The work is divided into two main parts. The first is a literary review study where stress is initially explained in general terms, with the definition of stress, stress theory, types of stress, stressors and symptoms of stress. Further there are described neural and hormonal mechanisms of stress and various hormones along with the endocrine glands which play an important role in the stress response. Then the paper deals with the possible effects of stress on the individual systems of the body. The following part is a description of mental disorders which are the effects of stress most associated. In the second part of the text is a proposal for research which presents a comparison of leaching of the stress hormone cortisol in individuals with posttraumatic stress disorder and healthy controls.
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Estimation of risks associated with the occurrence of synthetic thyroid
PECH, Michal
The aim of this work was to provide a comprehensive overview of published findings regarding thyroid, thyroid hormones, their concentrations, stability in the aquatic environment and effect on fish. To determine the consumption of synthetic thyroid hormones in the Czech Republic, the data on the distribution of the drugs, in which they are contained, is analyzed over a period of five years (2011 - 2015). This has provided information about the issued amount of active ingredients i.e. levothyroxine (T4) and liothyronine (T3) for each year. T4 consumption increased over five years, except for 2013, with the highest consumption in 2015 corresponding to 34.6 kg of T4. T3 consumption ranged only in tens of grams before prescribing drugs containing T3 in the Czech Republic was ceased in September 2013. Based on the distribution of synthetic thyroid hormones, an estimate of concentrations that could normally occur in surface water was performed (PECRIVER). Two variants of the calculation were performed. The first variant was based on consumption of synthetic thyroid hormones. The second variant was based on excretion of thyroid hormones (including natural ones) by humans. Each of these variants was counted with the F value, i.e. the rate of removal of the chemical during the WWTP wastewater treatment process, from two different sources. The first source was the study by Svanfelt et al. (2010) where the efficacy of thyroid hormone removal during the WWTP purification process was 66% for T4 (this value was not determined for T3). The second source was EPI Suite software, which calculated the theoretical efficacy of removal of T4 and T3 at WWTP (35.83% for T4 and 5.36% for T3). The resulting concentrations were relatively low in the first variant. The median of the estimated concentrations of thyroid hormones in surface water with the efficacy of removing thyroid hormones during the WWTP purification process, taken from the study by Svanfelt et al. (2010), ranged from 0.6 - 0.7 ng-l-1 for T4. Using the theoretical value of the elimination rate calculated using the EPI Suite program, the median ranged from 1.1 to 1.3 ng-l-1 for T4 and from 0.0007 to 0.0025 ng-l-1 for T3 before it ceased to be used in September 2013. In the second variant, the resulting concentrations were somewhat higher. Median of the environmental concentrations of thyroid hormone with the removal rate taken from the study by Svanfelt et al. (2010) was determined to 1.5 ng-l-1 for T4. With the EPI Suite removal efficacy, the median was determined to 2.9 ng-l-1 for T4 and 0.13 ng-l-1 for T3. Estimated concentrations of thyroid hormones in surface water may currently seem relatively low to have a significant effect on fish, since the lowest thyroid hormone concentration at which any effect was observed ranged in tens of ng-l-1. However, it should be borne in mind that thyroid hormones enter the surface water as a result of incomplete removal during waste water treatment and fish are exposed to these hormones over a long period of time, meaning that even seemingly low concentration may pose a potential risk to aquatic organisms including fish. The fate of these hormones in the environment is therefore to be judged by further studies and toxicological experiments.
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The canine mammary tumours
BÁRTOVÁ, Hedvika
The bachelor thesis deals with mammary tumors in dogs, causes, genetic foundation, hormonal factors, diagnosis of disease and choice of therapy. Then the bachelor thesis cites specific cases from the veterinary clinic. And at the end of this thesis there are confirmation and summary that mammary tumors are very common disease in females.
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Assessment of the drinking water treatment plant effectiveness via ecotoxicological tests and screening analyses
Nývltová, Barbora ; Mravcová, Ludmila (referee) ; Zlámalová Gargošová, Helena (advisor)
The quality of raw water is deteriorating with the continuous increase in environmental pollution. Raw water is being modified to drinking water by technological processes, and it is therefore necessary to put increased demands on the efficiency of these technological processes and their possible innovation. Due to the fact that raw water is contaminated with different types of pollutants, it is necessary to continuously control the drinking water supplied to the public distribution network in order to ensure its quality. Drinking water treatment is still unable to treat the raw water perfectly, its pollution is only reduced to acceptable standards. For this reason, it is indispensable that the quality of drinking water is being checked regularly and at the same time the efficiency of individual technological processes of drinking water treatment is assessed. This includes screening analysis or eventually ecotoxicological tests. The thesis focuses on the efficiency of technological processes of drinking water treatment. Within the experimental part, samples of raw water and samples of water after each separation stage have been collected at the drinking water treatment plant in the Czech Republic. These samples have been subjected to ecotoxicological tests and screening analysis. Based on the ecotoxicological tests carried out on Thamnocephalus platyurus, Lemna minor and Vibrio fischeri, we can assume the emergence of harmful chlorinated by-products, resulting to nearly 100% mortality in T. platyurus. The results of the screening analysis carried out indicate, after the extraction of specimens by the SPE method using HPLC/MS, that the most effective method for the removal of hormonal substances is ozonization.
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