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Vplyv vonkajších a vnútorných faktorov na vyrastanie kotylárnych pupencov hrachu
Kucsera, Attila
Apical dominance is one of the fundamental growth correlation phenomena in plant physiology. It is well known that auxin originates in the shoot apex and moving down in the stem to the root tip. This tip-to-base polar auxin flow maintains lower axillary buds in dormancy. When the shoot apex is removed and the auxin flow is disrupted, axillary buds can canalize and export their own auxin to the stem polar auxin transport system, establishing new auxin sources resulting in bud outgrowth. Besides stem axillary buds there are also two cotyledonary buds in pea (Pisum sativum L.) plantlets that were used as model system in this work. The cotyledonary buds are positioned in the vicinity of the stem and cotyledons. It is also known that cotyledons are rich auxin sources. In this work was shown that in cotyledone petioles PIN1 auxin efflux transmembrane proteins are localized in polar manner. This polarization indicates auxin flow from cotyledons to the main stem, suggesting that cotyledonary buds are maintained in dormancy by both stem and petiole auxin flows. Next, on different experimental models where stem auxin flow and/or auxin flow from the cotyledons was disrupted we shown that apex originated stem auxin flow had higher impact on cotyledonary bud outgrowth inhibition than cotyledon originated auxin. Furthermore, there was shown that the outgrowing pattern of cotyledonary buds can be influenced by light availability, suggesting some connection between auxin and the shade avoiding response. Last but not least there was also demonstrated that cotyledonary bud outgrowth mechanism is based on a same canalization principle as axillary bud outgrowth.
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Parasitic protease SmCB2 as a target for the treatment of schistosomiasis
Bakardjieva, Marina ; Mareš, Michael (advisor) ; Mikeš, Libor (referee)
Blood flukes of the genus Schistosoma are parasitic trematodes that cause schistosomiasis, a serious disease afflicting more than 240 million people. The proteolytic system of schistosomes is essential for their viability: it participates in important processes during host-parasite interactions such as food digestion, invasion and tissue migration. Thus, schistosomal proteases are promising molecular targets for therapeutic intervention in schistosomiasis treatment. The thesis focuses on the protease cathepsin B2 from S. mansoni (SmCB2) which has not been studied in detail so far in terms of biochemical properties and biological function. Recombinant SmCB2 was prepared using yeast and bacterial expression systems and was chromatographically purified. Using an in vitro activity assay, the first effective inhibitors of SmCB2 were identified which inhibited its proteolytic activity in submicromolar concentrations. Specific polyclonal antibodies against SmCB2 were prepared and used for immunomicroscopic localization of this protease on the surface of the parasite. ELISA analysis demonstrated that SmCB2 is a parasite antigen recognized by the host immune system in the mouse model of schistosomiasis. The thesis provides valuable information about SmCB2 as a potential target molecule for synthetic...
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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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