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Illumination with respect to biological functions
Němec, Jiří ; Štěpánek, Jaroslav (referee) ; Baxant, Petr (advisor)
The paper summarizes the basic light-technical parameters, the principles of visual and non-visual photoreceptions and the effects of light on the organism. Several chapters focus on the mechanism by which light affects hormone levels and the circadian rhytm of the organism. In relation to the lighting system, the impact of electromagnetic radiation, associated with the controls, on the body is also considered. Briefly described are systems based on smart LED light sources or smart switches. The result of the thesis is to choose the solution that best suits the requirements of the contracting authority.
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Vliv hygienicky ošetřené vody na srdeční frekvenci raka a jejich následnou mortalitu
MALINOVSKA, Viktoriia
The study is focused on the evaluation of crayfish physiological reaction on hygienically treated water with chlorine dioxide (ClO2). A patented non-invasive monitoring system was used for observation of crayfish cardiac and locomotor activity. Monitoring was conducted from February to August 2017 under conditions of private commercial enterprise "Pivovar Protivín" in Czech Republic. Adult individuals of signal crayfish, Pacifastacus leniusculus, were kept separately in water-flow aquariums directly after the water treatment device producing ClO2 in concentration from 0.01 to 0.29 mg.l-1. Observed crayfish response to the disinfectant varied among individuals which could be explained by a different functional state and individual reaction on stimuli. Diurnal rhythm of some crayfish was disturbed even at a lower concentrations of chlorine dioxide (0.01-0.2 mg.l-1), while higher concentrations affected all animals. In addition to that, higher levels of chlorine dioxide ( 0.2 mg.l-1) significantly increased mortality. Maximum concentrations (0.2-0.29 mg.l-1) were observed 28 times in total during 202 days of monitoring, which resulted in 25 mortality cases occurred several days after exposure. In average, mortality of crayfish occurred three-four weeks after stocking to the experimental system. Possible lethal concentration of ClO2, which caused animal mortality, is 0.2 mg.l-1. Results suggested that crayfish exposure to ClO2, obviously, negatively affect their physiological processes; however, further studies are needed to examine specific effects of chlorine dioxide on internal organs of crayfish.
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CIrcadian regulation of miRNA and clock-controlled genes in tumorigenesis
Balounová, Kateřina ; Pácha, Jiří (advisor) ; Bendová, Zdeňka (referee)
The circadian clock generates circadian rhythms, which participate on regulation of a number of signalling pathways. Disruption of the circadian regulatory mechanism is linked to a development and a progression of certain types of cancer including colorectal tumorigenesis. Progression of tumorigenesis depends on the cell cycle machinery related to cell proliferation and apoptosis. MiRNAs play a role in initiation and progression of tumorigenesis because they interfere in regulatory pathways associated with tumorigenesis. The aim of the thesis was to determinate existence of circadian rhytms in clock controlled genes (Tef, Dbp), miRNAs (miR-1-3p, miR-16-5p, miR-34a-5p, miR-155-5p, miR-192-3p) and genes of the cell cycle machinery (Ccnd1, Ccne1, Ccna1, Ccnb1) and apoptosis (Casp3, Bcl2, Bad). Further, to compare detected circadian rhythms during aging and neoplastic transformation of colon by quantitative RT-PCR. We have observed circadian expression of Tef, Dbp, Ccne1, Ccna1, Ccnb1, Casp3 and Bcl2 in young mice colon, Tef, Dbp, miR-1-3p, Ccne1, Ccna1 in old mice colon and Tef and Dbp in colorectal tumors. In summary, circadian expression of clock controlled genes varied but was maintained in mice colorectal tumors. In aging we demonstrated weakening of circadian rhythms of the genes of the cell...
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Iron and copper metabolism in marine microalgae of the genus Ostreococcus
Pilátová, Jana ; Šuťák, Róbert (advisor) ; Falteisek, Lukáš (referee)
The smallest free living eukaryote known as Ostreococcus tauri became along with some related species great experimental models for iron uptake research in marine picoplankton. The ecological context of such topic is very interesting considering the nature of adaptation to iron limitation and its connection to the copper metabolism. Our experiments has simulated iron and copper limiting conditions of the ocean, as a control we used iron and copper repleted cultivation media. The maximum cell counts were two- to threefold higher in iron-repleted medium compared to iron- depleted one. There was the only exception showing no difference in growth - O. lucimarinus coming from open ocean with high irradiance levels and very low iron concentrations, which all together made it the best adapted species. The reinoculation of cell cultures after a week cultivation into to the same iron/copper containing media led to unmasking the copper effect on growth, which was much weaker than encountered with iron (again except of O. lucimarinus). Iron sufficiency positively affects heme b and chlorophyll a and b content with no significant copper dependency. The circadian timing of heme b and chlorophyll a and b content shows the increasing trend during the day followed by decrease at night. This might be caused by...
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Circadian regulation of sleep during ontogenesis in humans
Grieblová, Adéla ; Sumová, Alena (advisor) ; Soták, Matúš (referee)
The circadian system has evolved as an adaptation to periodically changing conditions on Earth. In mammals, and therefore in humans, the circadian system consists of the central and perip- heral oscillators generating a circadian rhythm. One of the most significant process exhibiting circadian rhythm is the sleep-wake cycle. Sleep is regulated by cooperation of circadian and homeostatic process. There are changes in circadian regulation of sleep during ontogenesis in human. The changes mainly releate to chronotype, i.e., to the diurnal preferences of activity and sleep. In the first years of life, there is a typical morning chronotype. In the end of first decade of life, the circadian phase begins to delay and reaches its maximal eveningness during ado- lescence. In adulthood, the preference changes again toward morning chronotype and reaches extreme morningness in elderly. Changes in circadian regulation of sleep during ontogenesis depend not only on age, but also on sex. 1
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Role of microRNA in regulations of circadian rhythms and tumorigenesis
Balounová, Kateřina ; Pácha, Jiří (advisor) ; Červená, Kateřina (referee)
MicroRNAs (miRNAs) are ~22nt long single-strand RNA found in all groups of organisms, where they affect biochemical, physiological and behavioral pathways by regulation of protein expression. Regulation of protein expression is mediated by silencing mRNA of target genes in one of two processes, translation repression or degradation of mRNA. Changed expression of miRNA can lead to aberrant regulatory pathways resulting in various pathophysiological conditions like cardiovascular diseases, cancer or neurological disorders. MiRNA can play a role in cancer both as an oncogen or as a tumor suppressor, and it is tissue and cancer-type specific. In colorectal cancer miRNAs downregulate or upregulate signaling pathways including key processes involved in cancer development, like proliferation, cell cycle, apoptosis and metastasis formation. Circadian clock in mammals synchronizes cellular and physiological processes by transcriptional-translational feedback loops. Not only miRNAs regulate the levels of key clock genes and clock controlled genes, but also a number of miRNAs exhibit circadian expression. Therefore aberrant circadian rhythms increase risk of colorectal cancer also by altered expression of miRNAs. The main aim of the thesis was to identify miRNAs, which regulate both tumorigenesis and circadian...
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Determination of cortisol in saliva
Žánová, Magdalena ; Martínková, Markéta (advisor) ; Milichovský, Jan (referee)
This thesis deals with salivary cortisol levels measured by the ADVIA: Centaur CP Immunoassay System. Experimental saliva sampling was performed on 141 pro- bands from age 7 to 76. Volunteers were divided to groups according to their sex: males, females using hormonal contraceptives (HC) and females not using HC. Re- ference intervals of morning and evening salivary cortisol were defined: females not using HC 13,2 - 55,5 nmol/l and females using HC 15,5 - 44,2 nmol/l for mor- ning salivary cortisol. Females not using HC 4,0 - 16,6 nmol/l and females using HC 7,9 - 22,6 nmol/l for afternoon salivary cortisol. Males 15,8 - 47,7 nmol/l for morning salivary cortisol and 5,2 - 25,4 nmol/l for afternoon salivary cortisol. Dif- ferences in stated intervals were imperceptible in all monitored groups. However, it is necessary to maintain different reference intervals for both morning and evening sampling. Reference interval for morning sampling was 14,3 - 46,2 nmol/l and refe- rence interval for afternoon sampling was set at 4,0 - 22,2 nmol/l. Daily profiles of salivary cortisol were determined in 6 females and 4 males in four different parts of a day. The course of salivary cortisol levels corresponded in females not using HC, females using HC and males with circadian rhythm, which is subject to cortisol. Sa-...
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