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A conservation perspective on the mechanisms that influence plant-pollinator interactions
BIELLA, Paolo
Several aspects of plant-pollinator interactions are presented in the thesis. It contains a review on the open questions of plant-pollinator interactions from single species to complex networks. The following sections document novel results. Firstly, the conservation of complex pollination networks is addressed through the hierarchy of species' importance. In addition, the habitat requirements and interactions of a threatened rare pollinator species are explored. In the following chapters, the results from manipulative approaches applied in the field to plant-pollinator interactions are presented. The effect of pollinator's population decline on pollinators' foraging for pollen is investigated. Moreover, the way plant species loss impact several aspects of pollinator visitation is presented. Lastly, the impact of species removal on plant-pollinator network topology and on species ability of establishing new interactions is investigated.
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Helminths as causative agents of vertebrate cancers
Schreiber, Manfred ; Horák, Petr (advisor) ; Kolářová, Iva (referee)
Opisthorchis viverrini, Clonorchis sinensis, and Schistosoma haematobium have been classified as the group 1 of carcinogens by the International Agency for Research on Cancer. Infections with opisthorchid flukes may lead to the development of cholangiocarcinoma of the liver, and those with schistosomes to the squamous carcinoma of the bladder. The link between helminth infections and carcinomas has been confirmed, and the exact mechanisms of carcinoma induction are at present intensively studied. There are some other representatives of helminths that are probably associated with cancers, but their direct effect on the process of carcinogenesis has not been confirmed yet. The formation of tumors can also occur via malignant transformation of totipotent parasite cells that become invasive and metastasize to different parts of the host body. However, some types of helminths may exhibit an opposite effect and show an anti-tumor activity. This review primarily focuses on the helminths associated with the development of cancer and the currently described mechanisms of carcinogenesis caused by such infections.
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Flavonoids and natural coumarins interactions with conventional medicine
Sigmundová, Tereza ; Tůmová, Lenka (advisor) ; Mladěnka, Přemysl (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Supervisor: doc. PharmDr. Lenka Tůmová, CSc. Student: Tereza Sigmundová Title of Thesis: Flavonoids and natural coumarins interactions with conventional medicine Keywords: medicinal plant, flavonoids, coumarins, interactions The aim of this diploma thesis is to give an overview of the interactions between conventional drugs and simultaneous use of flavonoids, coumarins or medicinal plants containing flavonoids and coumarins. Cited literature includes articles published since 2000 till 2018, that were collected mostly using online databases (Web of Science, Science Direct, PubMed, Google Scholar). Flavonoids can affect the metabolism of drugs through interaction with CYP450 enzymes, P-glycoprotein, ABC or SLC transporters. This type of interaction is particularly important for drugs with narrow therapeutic index such as cyclosporin, digoxin or warfarin. Furanocoumarins contained for example in grapefruit juice cause irreversible inhibition of CYP3A4 enzyme and affect the pharmacokinetics of many drugs. The major drug classes that have been reported to present pharmacodynamic interactions with flavonoids or natural coumarins are anticoagulants, cytostatics and central nervous system agents. The thesis also describes...
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Interakce mezi organismy obývajícími jírovec maďal (Aesculus hippocastanum)
KOPAČKA, Michal
Ph.D. thesis is focused on the study of ecology and interactions among fungal disease horse chestnut leaf blotch, Guignardia aesculi, invasive pest horse chestnut leaf miner, Cameraria ohridella, and predatory mites of family Phytoseiidae. Ph.D. thesis consists of two main parts: 1) a detailed background research, and 2) six separate original published papers or manuscripts describing results of my own studies. The first study investigated spatial distribution of the first generation of C. ohridella in the urban environment in relation to the pest, the mortality of overwintering pupae at the end of vegetation season and the number of hatched C. ohridella and its parasitoids at the beginning of the following vegetation season. The second paper describes the interaction between C. ohridella and G. aesculi during vegetation season. The third and fourth papers deal with the effect of specific microctimatic conditions in site on the damage inflicted to horse chestnut leaves by G. aesculi. In addition, spatial distribution of G. aesculi in urban environment was studied. The fifth paper compared the species composition and the population density of Phytoseiidae between the Czech Republic and Greece. The sixth study described the species composition, abundance, population dynamics and sex ratio of phytoseiid mites inhabiting horse chestnut. The study also investigated, whether the abundance of predatory mites on horse chestnut leaves can be influenced by leaf damage caused by the horse chestnut leaf miner or G. aesculi during vegetation season.
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Interactions of apes and monkeys in tropical pavilons in the Prague zoo
Kloudová, Kateřina ; Vančata, Václav (advisor) ; Řezníček, Jan (referee)
Interactions of apes and monkeys in tropical pavilons in the Prague zoo The thesis is focused on the observation and subsequent assessment of the social behavior of primates, who are kept in a zoological garden. Part of the work is devoted to general characteristics of primates and their systematic classification. It also contains specific information about Prague zoological garden and its history. This work describes mutual interaction and social behavior of individuals within particular species of primates and their behavior once placed in common exhibition together with other animal species, both in closed quarters or pavilion, as well as in free range. The main objective of my work was to observe and evaluate social behavior from the point of view of both above mentioned cases. From the longtime observation we can conclude whether different groups of primates were gathered appropriately and if any mutual conflicts among them have occurred and could threaten the stability and relationship within monitored group. Regarding the contact with other animal species it was verified by the observation that chosen combination supports animal husbandry and helps the zoo staff to create better terms and conditions for breeding, corresponding to natural environment as much as possible. Keywords: zoo,...
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Interactions of herbivore funtion gourps and Succisa pratensis
Šulcová, Hana ; Janovský, Zdeněk (advisor) ; Roubíčková, Alena (referee)
Herbivory is one of most important factors which form meadow ecosystems. These ecological communities have one of the biggest variety of species in Central Europe and their research is important in terms of management of protected species as well. Localities which has a similar importance, is also a meadow ecosystem with occurrence of Succisa pratensis, the only host plant for rare butterfly Euphydryas aurinia. Research of Succisa and its other herbivores can improve a protection of this particular butterfly. Effects of herbivores of Succisa were examined by several experiments. The first one was a field cage experiment. Its aim was to detect what kinds of herbivores (rodents and invertebrates) are involved in herbivory of leaf rosettes of Succisa and what is their impact on the fitness of these plants. The intensity of herbivory of Succisa was measured for over two vegetation seasons on the month bases. In this experiment were also examined effects of surrounding vegetation on the studied plants of Succisa. The second experiment was performed in a garden. Its aim was to clarify the role of herbivores of leaf rosettes, stalks and their interactions on the fitness of Succisa. The third experiment was concerned to true bugs, which are pre-dispersal predators of seeds of Succisa. Their effects on...
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Preparation and characterization of hydrogels based on cationic biopolymer
Tesařová, Barbora ; Mravec, Filip (referee) ; Smilek, Jiří (advisor)
Presented thesis deals with the preparation and characterization of hydrogels based on positively-charged biopolymer and negatively-charged tenside. As an appropriate representative of positively-charged polymer was chosen chitosan, because of his biocompatibility and biodegrability, and N,N,N-trimethylchitosan, which was synthetised from chitosan in this diploma thesis. The final product of synthesis was characterised by SEC-MALS, elemental analysis, infrared spectroscopy and nuclear magnetic rezonation. Interactions between these polymers and representatives of negatively-charged tensides, which are sodium dodecylsuphate and sodium tetradecylsulphate, were investigated. The main method used in this thesis was rheology, through it were investigated prepared hydrogels based on chitosan and tensides and also prepared microgels based on N,N,N-trimethylchitosan and tensides. The interactions between polymers and tensides have been proved.
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