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Approaches to pupils in need of support at primary school during the COVID-19 pandemic
KREJČOVÁ, Tereza
The bachelor's thesis deals with approaches to pupils in need of support at the first level of primary school during distance learning from March 2020 to March 2021. The theoretical part focuses on the topic of socialization, further describes individual approaches to education, obstacles to social inclusion, support options, inclusion in abroad, distance education and relevant legislation. In the practical part, the basic research problem, research methods, research questions and the goal of the investigation are presented. In the conclusion, the data analysis, summary of the investigation and discussion are detailed.
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The mechanism of impaired formation of head-tail coupling apparatus in centrobin deficient acephalic spermatozoa
Vlčková, Monika ; Frolíková, Michaela (advisor) ; Krejčová, Tereza (referee)
Acephalic sperm syndrome (ASS) is a rare form of teratozoospermia that is probably genetic in origin. The sperm of individuals with this syndrome have a damaged apparatus connecting the head and flagellum (HTCA), which leads to the formation of acephalic sperm, i.e. sperm with separate heads from flagella. Individuals affected by ASS are almost exclusively infertile. One of the proteins whose mutation causes ASS is SUN5. Together with KASH proteins, SUN proteins are part of the so-called LINC complex, which ensures the connection of the nucleoskeleton with the cytoskeleton. Centrobin is a protein involved in centriole duplication and assembly of the dividing spindle. Rats carrying a defective gene for centrobin have reduced fertility and exhibit an ASS phenotype. For that reason, this model organism was used in this work to study the possible interrelationships of proteins involved in the formation of ASS. Given the similar phenotype of centrobin and SUN5 mutated spermatozoa, there is a possibility that centrobin interacts with one of the LINC complex proteins and together they participate in the formation of the head-flagella junction. Sperm from rats with a defective centrobin gene also show significant damage to the flagella. Decreased Odf1 protein expression has previously been reported in ASS...
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Glycoprotein profile of human ejaculate as a marker of its quality
Pavlová, Hana ; Postlerová, Pavla (advisor) ; Krejčová, Tereza (referee)
Glycoproteins are an indispensable component of the sperm glycocalyx. They arise through the process of co-translational or post-translational modification, so-called glycosylation, during which carbohydrate chains are attached to a peptide chain. Glycoproteins are involved in reproductive processes and their presence is often key to successful fertilization. The degree of glycosylation of glycoproteins is highly variable and is determined by the representation of carbohydrate units in glycans. It has already been found that the degree of glycosylation can be related to the fertility of an individual. The diploma thesis is focused on the comparison of the representation of terminal saccharides, sialic acid and fucose, in the glycoproteins of sperm and seminal plasma of patients with normal and abnormal ejaculate parameters. The total rate of sialylation and fucosylation in the seminal plasma was determined, as well as the rate of sialylation and fucosylation of specifically detected glycoproteins of sperm and seminal plasma. A significant difference was noted only in the detection of total fucosylation of seminal plasma glycoproteins. However, subsequent correlation tests revealed important relationship between the degree of sialylation and fucosylation of glycoproteins and ejaculate parameters,...
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Expression and localization of alpha V and alpha 3 integrins in male germ cells of selected mammalian species
Bajerová, Kateřina ; Frolíková, Michaela (advisor) ; Krejčová, Tereza (referee)
Integrins are transmembrane glycoproteins mediating cell-cell adhesion and ensuring communication between extracellular matrix and cell cytoskeleton. The presence of integrin subunits has already been described on somatic cells, as well as on oocytes and sperm cells. In oocyte plasma membrane, integrins together with tetraspanins are involved in the formation of vast molecular webs. Analogical structures have been recently discovered in sperm plasma membrane as well. While the role of integrins on oocyte has been researched quite extensively, there is much less known about its presence and function on sperm. This Master's thesis focuses on expression and localization of integrins alpha V and alpha 3 on acrosome-intact sperm and its comparison between mouse, pig and human sperm cells. Furthermore, this thesis also describes relocation of the alpha V integrin after the acrosome reaction, which is an essential step of sperm maturation. Using confocal microscopy, the alpha V integrin localization was detected in acrosomal cap area of acrosome-intact sperm of all selected species. After acrosome reaction, the alpha V integrin relocated and was depicted in postacrosomal region and equatorial segment of acrosome-reacted sperm. Immunodetection revealed a decreasing expression of the alpha V integrin in...
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Marketing Strategy of the Selected Company
Šperlík, Max ; Krejčová, Tereza (referee) ; Chlebovský, Vít (advisor)
This master thesis is focused on increasing the competitiveness of the company “Pizzerie U Kalichu” by creating new marketing strategy. The work is divided into three main parts. The first part describes the theoretical knowledge associated with this topic. Second part is focused on the analysis of the current situation in the company. From these facts and dates we found out is created the third part, which is focused on the suggestion for improvement a marketing strategy. These improvements should lead to gain new customers, increase a profit for the company and increase a competitiveness of the company on the market.
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Effect of ubiquitin-proteasome system on spermiogenesis in mammals
Kroumanová, Kristýna ; Petelák, Aleš (advisor) ; Krejčová, Tereza (referee)
Spermiogenesis is a complicated process in which the haploid spermatids differentiate into morphologically mature sperm. Morphological changes include condensation of chromatin and histone-to-protamine replacement, fusion of Golgi-derived vesicles to form acrosomal cap, flagellum formation, reduction of cytoplasmic volume and organelles rearrangement. Ubiquitin-proteasome system plays a key role in these processes. Ubiquitination is a posttranslational modification, leading to the labelling of intracellular proteins targeted for degradation by 26S proteasome. Importance of sperm ubiquitination, is supported by the fact, that deficiency of ubiquitin-proteasome system can lead to infertility at various degrees. During the subsequent sperm maturation in the epididymis extracellular ubiquitination of abnormal sperm and sperm quality control take place. Ubiquitin-proteasome system plays a key role during fertilization, when the sperm 26S proteasome is co-responsible in zona pellucida penetration. The purpose of this assay is to describe the effect of ubiquitin- proteasome system during different stages of spermiogenesis in mammals.
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Photoreceptors properties in strictly subterranean African mole-rats
Krejčová, Tereza ; Němec, Pavel (advisor) ; Kott, Ondřej (referee)
4 Photoreceptor properties and distribution in strictly subterranean African mole-rats (Rodentia, Bathyergidae) The visual system of subterranean rodents is assumed to be regressed in response to their lightless ecotope. According to the prevailing doctrine, negative or non-selective processes have driven evolutionary regression of the visual system in many unrelated groups of rodents that has adopted strictly subterranean mode of life. Among rodents this has been exemplified by detailed studies of the blind mole-rat Spalax ehrenbergi. However, recent studies involving a larger spectrum of subterranean rodent species demonstrated unexpected diversity of retinal properties and visual system designs among subterranean rodent species and thus challenged the widely held view that the visual system has undergone extensive convergent evolution in subterranean mammals. This paper examines the presence, the distribution, and photoreceptor properties in the African mole-rats (Bathyergidae, Rodentia). It describes rodopsin, S- and L-opsin expression patterns, photoreceptor densities and rod/cones proportions in five species of bathyergid mole-rats, namely Bathyergus suillus, Georychus capensis, Fukomys damarensis, Cryptomys natalensis and Heliophobius argenteocinereus. Spectral cone types and rods were assessed...
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Effect of hydrogen sulphide on aging of porcine oocytes in vitro
Krejčová, Tereza ; Petr, Jaroslav (advisor) ; Ješeta, Michal (referee)
Unfertilized or parthenogenetically non-activated porcine oocytes matured in vitro conditions are subjected to a process known as aging. During such development, porcine oocytes undergo the complex of the structural and functional changes, which can result in spontaneous parthenogenetic activation, fragmentation or lysis. After three days of culture in our condition, 23% of oocytes remained at the stage of metaphase II, 48% of oocytes were spontaneously parthenogenetically activated, 26% of oocytes were subjected to fragmentation and 3% of oocytes were lysed. The complete suppression of porcine oocyte fragmentation during the process of aging occurred during oocytes cultured in medium with sulphide donor Na2S in concentrations 150 µM and 300 µM. Inhibition of enzymes catalyzing the synthesis of hydrogen sulfide in the oocytes during the process of aging (cystathionine-gamma-lyase and cystathionine beta-synthase), iniciates earlier onset of oocytes fragmentation. The effect of both inhibitors could be completely reversed by using sulphide donor Na2S. The process of aging in porcine oocytes significantly reduces the success of the activation processes. Parthenogenetic activation occurred in 94% of pig oocytes, which were not subjected to aging. The proportion of activated oocytes after exposure to 24...
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