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Functional analysis of sperm quality after endocrine disruptor treatment
Linhartová, Zuzana ; Liberda, Jiří (advisor) ; Ryšlavá, Helena (referee)
The aim The aim of my study was to determine whether the selected endocrine disruptors (EDs) affect reproductive parameters of sperm. Due to two experimental models, in which was tested the influence of selected Eds, my work is divided into two parts: A) On the boar model (Sus scrofa) was tested effect of selected EDs (zearalenone (ZEN), di(2-ethylhexyl) phthalate (DEHP), vinclozolin (VIN) on the course of capacitation, acrosome responses in vitro and changes in the detection and localization of selected proteins. B) On the fish model (Perca fluviatilis L.) was tested the influence of the selected ED- bisphenol A (BPA) on the motility and velocity of fish sperm movement. Results Mammalian model In mammalian model the course of capacitation and acrosome reaction was significantly influencing by the examined EDs in comparision with control samples. The increase of the number of marked cells during capacitation and reduce of the number of marked cells after AR compared with the differences between experimental and control samples was confirmed by the flow cytometry method. At higher concentrations EDs clearly inhibited acrosome response and thus reduce the number of sperm capable of fertilization. The relevancy of the results of detection acrosome reaction was confirmed by using various methodological...
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Mikromanipulace a kryopreservace zárodečných buněk ryb
LINHARTOVÁ, Zuzana
The induction of germ-line chimerism is an expanding focus of fisheries research. This technique is having a potential to enhance the production of gametes of species that are commercially valuable, endangered, species with problematic reproduction, using a more common or easily available species or species adapted to artificial reproduction as a surrogate host. The main goal of this technology is to establish a small-bodied surrogate broodstock producing functional donor gametes based on germ cell transplantation. Extent preliminary experiments, including documentation of donor/host embryonic and larval development, characterization of germ cells enriched by documentation of their migratory activities, sterilization of the host, isolation and cryopreservation of donor germ cells, are key factors for launching this biotechnology. All these crucial points were the main objective of the present work. The whole thesis provided the focus on two different fish species. First, our commercially valuable fish, the tench, where we would like to apply our current knowledge to create a germ-line chimera within cyprinids by transplantation of tench germ cells to smaller and faster-reproducing fish species as white cloud mountain minnow. Secondly we focused on the endangered species (listed in IUCN Red List) of large body size with long reproductive cycle, the sturgeons. In this case, we have chosen sterlet as a host, providing an advantage of shorter generation interval and smaller body size, to produce gametes of donor, a critically endangered species of large body size with long reproductive cycle, such as beluga. This innovative technology could result in collection of sperm and eggs in shorter time from small-bodied host. In tench we firstly focused on embryonic and larval development documentation together with description of origin and migration pathways of primordial germ cells (PGCs). PGCs represent a powerful tool for creation a germ-line chimera within fish species because they transmit genetic information to the next generation (Linhartova et al., 2014a). Secondly, we reported a practical technique for isolation and cryopreservation of early stages of germ cells (GC), including spermatogonia (SG) and spermatocytes (Linhartova et al., 2014b). In case of sturgeons, Saito et al. (2014) firstly described the origin and migration patterns of sturgeon PGCs deposited at the vegetal pole of the egg similar to that in anurans. Secondly, Psenicka et al. (2015) reported isolation and cryopreservation of female and male GC, SG from testes and OG and pre-vitellogenic oocytes from ovary, of 2-4-year old Siberian sturgeon. Moreover the isolated GC were transplanted into host (sterlet) and process of transplantation resulted in successful colonization of sterlet genital ridge. The potential host for germ-cell tranplantation, sterlet, was sterilized by knock-down of germ cell specific gene, the dead end gene, by the morpholino antisense oligonucleotide (MO) agent (dnd-MO). These results reported the first known and functional method of sturgeon sterilization (Linhartova et al., manuscript). We provided important information on morphology and ultrastructure of beluga spermatozoa structure by scanning and transmission electron microscopy to increase knowledge of evolutionary and taxonomic relationships among sturgeons (Linhartova et al., 2013). Finally, this thesis presents several studies with differing focus of research but with one target goal to induce germ-line chimerism in fish. All these results are prerequisite of future application and development of surrogate production in these species.
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Corporate social responsibility jako součást strategie malé firmy
Linhartová, Zuzana ; Džbánková, Zuzana (advisor) ; Černá, Iva (referee)
Cílem této práce bylo zmapování situace konceptu CSR se zaměřením na malý podnik. Stěžejní přínos pak spočívá především v aplikaci konkrétního návrhu CSR a jeho implementace do celkové podnikatelské strategie reprezentanta malých a středních podniků ? výzkumné agentury Market Vision, s.r.o.Jednotlivé kroky implementace CSR jsou navrženy z hlediska COSORE ? Balance ? Scorecard modelu, ve kterém se na tuto problematiku nahlíží ze čtyř základní perspektiv ? zainteresovaných stran, finanční, procesní a perspektivy učení a růstu. Zásadním bodem této části práce byla identifikace všech důležitých aktivit v podniku, které se týkají modelu CSR a pomocí dotazování se zjišťuje, kde se firma již realizuje a v jakém směru má stále rezervy pro naplnění hlavních myšlenek konceptu.
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