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Mechanisms of the karyotype evolution in scorpions (Arachnida: Scorpiones)
Štundlová, Jana ; Šťáhlavský, František (advisor) ; Špakulová, Marta (referee) ; Marec, František (referee)
Scorpions represent an ancient group of arachnids that have colonized a diverse range of terrestrial environments since Silurian times. Despite their long evolutionary history and ecological diversity, these animals are characterized by morphological stasis. However, the uniform morphology of extant scorpions may hide the true diversity of contemporary lineages. The study of cytogenetic traits thus has the potential to deepen our knowledge of the diversity of contemporary scorpion taxa and bring new insight into the processes underlying karyotypic changes in this group of arachnids. The subject of this thesis is to examine the diversity and dynamics of karyotypes of selected scorpion groups with holokinetic and monocentric chromosomes. Comparative cytogenetic analysis, including more than 110 species from five families, was based on standard cytogenetic techniques and mapping of the gene for 18S ribosomal RNA and telomeric (TTAGG)n repeats by fluorescence in situ hybridization (FISH). To elucidate the fundamental structural mechanisms underlying karyotype differentiation in the studied groups, the emphasis was placed on the interconnection of cytogenetic and sequence data of the analyzed species. The knowledge of the genetic structure and phylogenetic relationships of studied taxa played a crucial...
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BIRD SCHISTOSOMES: development of schistosomula with focus on Trichobilharzia spp
Chanová, Marta ; Horák, Petr (advisor) ; Špakulová, Marta (referee) ; Haas, Wilfried (referee)
5 ABSTRACT Schistosomulum is the first stage developing in definitive host body, affecting various body parts and in the case of bird schistosomes present in host tissues for longest period. The aims of the present thesis are to summarize recent knowledge of bird schistosomula migration, development and pathogenic impact on host tissues and complete the details for two model species (Trichobilharzia szidati and T. regenti) with different life strategy. The other aim was to introduce and test the method for in vitro cultivation of schistosomula. Schistosomulum is formed by transformation of cercaria in the host skin at the time of penetration. The process is preceded by cercarial tail detachment and includes emptying of penetration glands and extensive surface changes. All this take place also under defined in vitro conditions. Transformed schistosomula migrate towards the target organ in host body. Depending on the species schistosomula migrate via the circulatory system or nervous tissues and the migration is directed either to intestinal or nasal area (visceral or nasal species, respectively). Specific migratory pattern for lung passage of T. szidati and migratory route of T. regenti through the nervous system, unique among schistosomes and including intra- and extra vascular location, are obligatory for...
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Mechanisms of the karyotype evolution in scorpions (Arachnida: Scorpiones)
Štundlová, Jana ; Šťáhlavský, František (advisor) ; Špakulová, Marta (referee) ; Marec, František (referee)
Scorpions represent an ancient group of arachnids that have colonized a diverse range of terrestrial environments since Silurian times. Despite their long evolutionary history and ecological diversity, these animals are characterized by morphological stasis. However, the uniform morphology of extant scorpions may hide the true diversity of contemporary lineages. The study of cytogenetic traits thus has the potential to deepen our knowledge of the diversity of contemporary scorpion taxa and bring new insight into the processes underlying karyotypic changes in this group of arachnids. The subject of this thesis is to examine the diversity and dynamics of karyotypes of selected scorpion groups with holokinetic and monocentric chromosomes. Comparative cytogenetic analysis, including more than 110 species from five families, was based on standard cytogenetic techniques and mapping of the gene for 18S ribosomal RNA and telomeric (TTAGG)n repeats by fluorescence in situ hybridization (FISH). To elucidate the fundamental structural mechanisms underlying karyotype differentiation in the studied groups, the emphasis was placed on the interconnection of cytogenetic and sequence data of the analyzed species. The knowledge of the genetic structure and phylogenetic relationships of studied taxa played a crucial...
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BIRD SCHISTOSOMES: development of schistosomula with focus on Trichobilharzia spp
Chanová, Marta ; Horák, Petr (advisor) ; Špakulová, Marta (referee) ; Haas, Wilfried (referee)
5 ABSTRACT Schistosomulum is the first stage developing in definitive host body, affecting various body parts and in the case of bird schistosomes present in host tissues for longest period. The aims of the present thesis are to summarize recent knowledge of bird schistosomula migration, development and pathogenic impact on host tissues and complete the details for two model species (Trichobilharzia szidati and T. regenti) with different life strategy. The other aim was to introduce and test the method for in vitro cultivation of schistosomula. Schistosomulum is formed by transformation of cercaria in the host skin at the time of penetration. The process is preceded by cercarial tail detachment and includes emptying of penetration glands and extensive surface changes. All this take place also under defined in vitro conditions. Transformed schistosomula migrate towards the target organ in host body. Depending on the species schistosomula migrate via the circulatory system or nervous tissues and the migration is directed either to intestinal or nasal area (visceral or nasal species, respectively). Specific migratory pattern for lung passage of T. szidati and migratory route of T. regenti through the nervous system, unique among schistosomes and including intra- and extra vascular location, are obligatory for...
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Molecular diagnostics of giant liver fluke (Fascioloides magna)
Siegelová, Veronika ; Špakulová, Marta (referee) ; Kašný, Martin (advisor)
Fascioloides magna (giant liver fluke) is veterinary important endoparasitic helminth parasitizing in a number of vertebrate species (primarily in ruminants), causing them severe health problems, often leading to death. The F. magna adults are mostly localized in the liver tissue of the definitive hosts, where they survive in pseudocysts for a long time and produce eggs. The eggs are released from the pseudocysts via the bile ducts into the gut and then leave the host's body together with faeces. Up to now, the diagnostics of fascioloidosis is primarily based on the dissection of the host's liver. The direct and indirect intravital diagnostic methods could represent an appropriate alternative. Using the intravital diagnostic methods, the parasitosis can be revealed either directly (microscopically) - by discovering the eggs in the host's faeces or indirectly (molecularly) - by isolation of the parasite's DNA and the subsequent PCR. The molecular diagnostic methods also allow the reliable differentiation of F. magna infection from the other eventual trematodosis (caused by e.g. Fasciola hepatica, Dicrocoelium dendriticum, Paramphistomum cervi).
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