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Analysis of spermatogenesis in mice C57BL/6 after Toxoplasma gondii infection.
Šidlová, Adéla ; Hortová, Kateřina (advisor) ; Flegr, Jaroslav (referee)
Toxoplasma gondii is an intracellular parasite that causes a persistent infection in 10- 80% of the world's population, depending on geographic location. Infection with this parasite causes changes in behavior and physiological functions of an infected host, including warm- blooded animals including humans. Recent studies also show influence of infection with T.gondii on male reproductive fitness in mice and rat and to investigate this issue further became a task of my diploma thesis. In this study, detailed histometric screening of testicular function along with levels of a pituitary luteinizing hormone (LH) and screening of epigenetic modification of testicular DNA were analysed in infected and control mice. Testicular function and sperm production was significantly decreased in T. gondii positive group after a 30-day infection. The level of LH in urine of T. gondii infected mice was decreased compares to control and the number of leptotene primary spermatocytes and spermatids was lowered, but also number of Sertoli cells and tubule diameter were elevated. In epigenetic study the testicular epigenom was tested to measure global methylation and methylation of specific genes Hspa1, Crem and Creb1 which are essential for successfully ongoing spermatogenesis. The global level of methylation of...
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The process of translocation in Ostrov nad Ohří (Schlackenwerth). The origin and development of the church of St Jacob and the church of St Nicolas according to the urbanization
Šídlová, Andrea ; Scholz, Stefan (advisor) ; Záruba, František (referee)
The thesis should notice the time when the two churches arose by looking back at the historical situation in the 13th century Premyslid Bohemia. Furthermore, we will try to evaluate the social, legal and property situation of the given area, and it will monitor the development and building. The work is given a chapter on the administrative area of Sedlecko to point out conflicts of interest of Czech kings and Roman rulers in this territory and the formation of the state historic town of Cheb and between the 12th and 13th century. The origins of Ostrov agglomeration is linked to the family of Hrabišic. The following chapter discusses their family, their asset base and foundation. The main part is devoted to the translocation and the relocation of settlements from the center of the parish church of St. James to St. Nicholas. The reason was, as it was previously shown, an unsatisfactory position of the original settlement for its further development, which was necessary for the competitiveness of the local market center. It subsequently evolved into a town. This situation culminated in the privilege of King John of Luxembourg. At that time a new and relatively big church was being built which replaced the church of St. James. It was a part of the settlement and farmstead of the family of Hrabišic and...
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Influence of estrogens on mammalian sperm.
Šidlová, Adéla ; Šebková, Nataša (referee) ; Hortová, Kateřina (advisor)
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, whether their effect is positive or negative. Endogenous estrogens in mammalian males are an important part of the endocrine system. Estrogens play an important role in the growth and maintenance of bone mass, as well as in the development of germ cells and in the marches of spermatogenesis. Healthy sperm are essential for successful reproduction. Effect of endogenous estrogens is partly involved in the regulation of proper development of sperm. Besides the positive effect of endogenous estrogens, there is also a negative effect of estrogens from the external environment, so-called environmental estrogens. Between environmental estrogens are man-made chemicals, xenoestrogens, which increasingly contaminate the environment. Hazards of these estrogenic substances in nature is hidden in their ability to act as endocrine disruptors, which cause defects in many aspects of mammalian reproduction. With regards to the fact that there are more and more substances in current environment that can interfere with hormonal path of mammalian reproduction, it is important to look at this issue. Reproductive disorders that may be caused by...
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One more drop for decreasing reproduction
Dvořáková-Hortová, K. ; Šídlová, A. ; Děd, Lukáš ; Hladovcová, D. ; Vieweg, M. ; Weidner, W. ; Steger, K. ; Stopka, P. ; Paradowska-Dogan, A.
Toxoplasma gondii is a common protozoan parasite that infects warm-blooded animals throughout the world, including mice and humans. During infection, both, the parasite and the host, utilize various mechanisms to maximize their own reproductive success. Mice and humans are both the intermediate hosts for Toxoplasma gondii, which forms specialized vacuoles containing reproductive cysts in the formers’ tissue. As half of the human population is infected, developing a disease called toxoplasmosis, along with an ever-growing number of couples suffering with idiopathic infertility, it is therefore surprising that there is a lack of research on how T.gondii can alter reproductive parameters. In this study, a detailed histometric screening of the testicular function along with the levels of the pituitary luteinizing hormone (LH) were analysed in infected mice. Data on relative testis and epididymis weight, and sperm count were also collected. Based on the results obtained, the level of LH in the urine of Toxoplasma gondii infected mice was lower compared to the control. In direct correlation with the hormone level, testicular function and sperm production was also significantly lower in T. gondii positive group using sperm count and histometric analysis as a marker. Not only were the number of leptotene primary spermatocytes and spermatids lowered, but the number of Sertoli cells and the tubule diameter were elevated. In parallel, a pilot epigenetic study on global testicular methylation, and specific methylation of Crem, Creb1 and Hspa1genes essential for successfully ongoing spermatogenesis was performed. Global methylation was elevated in Toxoplasma infected mice, and differences in the DNA methylation of selected genes were detected between the Toxoplasma positive and control group. These findings demonstrate a direct relation between T. gondii infection and the decrease of male reproductive fitness in mice, which may contribute to an increase of infertility in humans.
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