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Migration and pathogenicity of neurotropic helminths
Pech, Václav ; Horák, Petr (advisor) ; Chanová, Marta (referee)
A neurotropism of helminths can be observed in their intermediate, paratenic and definitive hosts. Neurotropic helminths migrate through the nervous tissue, where maturation and reproduction can take place. The neurotropic helminths can be found in the family of trematodes (Diplostomum baeri, D. phoxini, Ornithodiplostomum ptychocheilus, Trichobilharzia regenti), cestodes (Taenia multiceps, T. solium) and nematodes (Angiostrongylus cantonensis, Elaphostrongylus cervi, Parelaphostronglus tenuis, Baylisascaris procyonis). Presence of these helminths in the nervous tissue can (usually with contribution of the immune system) lead to neurological or other pathological changes: the infected hosts can even die. Some of the neurotropic helminths (A. cantonensis, B. procyonis, T. solium, T. multiceps) can infect humans as well.
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Differentiation of totipotent germinal cells in larvae of bird schistosomes
Peštová, Jitka ; Horák, Petr (advisor) ; Chanová, Marta (referee)
This thesis aims to explore the larval development of a bird fluke Trichobilharzia regenti in its intermediate hosts, as well as the processes of differentiation of its embryonal cells and the differentiation between sporocystogenesis and cercariogenesis in sporocysts, with the ultimate goal to find out whether it is possible to find multiple generations of daughter sporocysts throughout the development of avian schistosomes in the intermediate hosts, just like in the case of human schistosomes of genus Schistosoma. Five developmental stages of daughter sporocysts, and ten developmental stages of cercariae have been defined. The first developmental stage in both larvae is the germinal cell. It divides and gives rise to a cell agregate. Afterwards an envelope (primitive epithelium) is formed around the embryo and subsequently, the embryo elongates. At this stage, the development of the two larvae undergoes different pathways. We can distinguish daughter sporocyst from cercaria in the phase, when the tegument is completed. The daughter sporocyst acquires characteristic vermiform appearance, and its body cavity contains plenty of germinal cells. For cercariae with an developed tegument, presence of the penetration glands is characteristic. Key words: Trichobilharzia regenti, germinal cells, mother...
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Cathepsins L of Diplostomum pseudospathaceum cercariae
Perháčová, Terézia ; Mikeš, Libor (advisor) ; Hartmann, David (referee)
This study is focused on cercarial cysteine peptidases of the trematode Diplostomum pseudospathaceum. It follows previous research which confirmed the presence of a 24kDa cysteine peptidase in cercariae biochemically and by mass spectrometry. It was postulated, that the function of this peptidase is histolytic, when cercariae penetrate the tissues. During an attempt to purify this peptidase and characterize its peptidolytic activity, it was found out that the cercarial homogenate containsmore different peptidases varying in their pI. Tests of peptidolytic activity and inhibition have shown that these peptidases are cathepsin L-like. They are active over a broad spectrum of pH with optima of activities in weakly acidicor neutral pH. Using degenerate primers based on conserved motifs of cysteine pepridases, partial sequences of three genes for cathepsin L of D. pseudospataceum (DpCL1, 2 a 3) were obtained. Then the complete sequences of DpCL2 and 3 genes and partial sequence (without 5'end) of DpCL1 were obtained by RACE PCR. To confirm function of these peptidases we tried to immunolocalize them. We assumed that they are localized in penetration glands. Preliminary results suggested that some of the cathepsins could be also localized in the gut of cercariae. For more detailed biochemical...
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Biologically active compounds of selected model trematodes
Kurečka, Martin ; Kameník, Zdeněk (advisor) ; Mikeš, Libor (referee)
Trematoda are parasites known for their ability to manipulate their host for survival and reproduction. They have complex life cycles with the intermediate host represented by mollusks and the definitive host, represented by vertebrates. This work focuses on three medically important genera of trematodes: Schistosoma, Fasciola and Opisthorchis. The aim of this work is to summarize biologically active low molecular weight substances that parasites modulate or produce in order to manipulate their host. The result of the work is a literature research of a comparative change in the concentration of metabolites of infected and uninfected trematode hosts with a focus on the analytical method used. Metabolomics deals with a comprehensive analysis of the metabolism of biological samples. It uses spectrometric analytical methods such as nuclear magnetic resonance and mass spectrometry combined with gas or liquid chromatography. Part of the work is also a summary of the importance, development and perspectives of metabolic profiling in parasitology. Current research in this area focuses mainly on vertebrate hosts. In addition, for vertebrate hosts, the sum of studied substances is still much broader than that in intermediate hosts. In intermediate host studies also focus on different types of substances,...
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Influence of bird schistosome Trichobilharzia regenti on haemocyte activity of lymnaeid snails
Skála, Vladimír
Gastropod molluscs are naturally exposed to various pathogens such as bacteria, or multicellular parasites that include digenetic trematodes (digeneans) which develop in snails. To combat these pathogens gastropods have evolved a sophisticated internal defence system that is composed of humoral and cellular arms. Lectins are probably the most important humoral components, whereas haemocytes represent the main effector cells. Immunity is one of the important factors determining compatibility/non-compatibility of gastropods and pathogens (particularly snails and trematodes). The introductory part of this thesis includes a review of literature focused on the components of the gastropod immune system and their reactions against pathogens represented by bacteria and digeneans. Additionally, selected immunomodulations caused by compatible digenean species are reviewed. Experimental work (presented in publications) focused mainly on the influence of the bird schistosome Trichobilharzia regenti on haemocyte activities of two lymnaeid snail species, Radix lagotis and Lymnaea stagnalis that are susceptible or refractory to the parasite, respectively. This schistosome parasite causes neuromotor disorders in specific definitive hosts (waterfowl), but it also causes cercarial dermatitis in accidental hosts...
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Endoparazitózy ovcí na konvenčních farmách a biofarmách
Vomáčková, Karolína
The aim of this thesis is to assess the difference in prevalence of endoparasites in sheep bred on conventional farms and on organic farms. The theoretic part consists of a literary research on the basis of both domestic and foreign literature dealing with the problem of endoparasitic nematodes, tapeworms and coccidia in sheep. According to this research it is possible to identify seven perilous species of coccidia, fourteen species of intestinal nematodes, two species of lung nematodes, two species of tapeworms and two species of trematodes in the Czech Republic. The practical observations were carried out using nondestructive coprological techniques throughout the year 2016. Four species of coccidia (Eimeria bakuensis, Eimeria ovinoidalis, Eimeria parva, Eimeria crandalis), seven species of intestinal nematodes (Haemonchus concortus, Trychostrongylus spp.axei, Nematodirus spp., Cooperia curticei, Bunostomum trigonocephalum, Chaberia ovina, Oesophagostomum venulosum), one species of lung nematodes (Protostrongylus rufescens) and one species of tapeworms (Moniezia expansa) have been identified during the analysis. The prevalence of parasites and intensity of infection differed according to the type of farming, type of sheep care (incl. deworming) and also time of year. In total the organic farming has been assessed the healthier farming type. The practical outcome therefore is a recommendation for conventional farms to pay more attention to the sheep care with respect to the life cycles of the parasites.
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Vliv chovatelského prostředí na výskyt endoparazitů ovcí na Tišnovsku
Vomáčková, Karolína
The aim of this thesis was to survey the problem of endoparasitic nematode, cestode, trematode and coccidia infections in sheep and their connection with the farming conditions and zoo-hygienic care. We have found out that 7 species of coccidia, 14 species of gastrointestinal nematodes, three species of lung nematodes, two species of cestodes and four species of trematodes can be found in local conditions. Further we discussed possible ways of suppressing the infections in the breeding environment. The practical coprological examination took place in autumn 2018. We've examined fecal samples from 10 different sheep farms in the Tišnov region, 100 samples in total. We've discovered four species of coccidia (Eimeria bakuensis, E. crandalis, E. parva, E. ovinoidalis), eight species of gastrointestinal nematodes (Bunostomum trigonocephalum, Cooperia curticei, Haemonchus contortus, Chabertia ovina, Nematodirus spp., Oesophagostomum venulosum, Trichuris ovis, Trichostrongylus spp.), two species of lung nematodes (Muellerius ca¬pillaris, Protostrongylus rufescens) and one cestode species (Moniezia expansa). Prevalence and intensity of the infection varied greatly among the farms. We concluded that administering feed supplements during lambing had the most noticeable positive effect on the infection course.
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Aporocotyle simplex fluke from the flounder Hippoglossoides platessoides in Svalbard.
HÁJKOVÁ, Šárka
In my bachelor thesis I studied trematodes from plaice Hippoglossoides platessoides obtained during expeditions to Svalbard in 2014 and 2018. My goal was morphological and molecular processing of the obtained material, which allowed me to confirm the identification of the flukes as Aporocotyle simplex Odhner, 1900. Aporocotyle simplex is a common parasite of plaice, ocurring mainly in Hippoglossoides platessoides, but also in Limanda limanda and Pleuronectes platessa. The species A. simplex is geographically distributed in the Gulf of St. Lawrence in Canada, off the west coast of Sweden, in the Barents Sea and Bering Sea, off the coast of Kamchatka and Greenland. My results showed that the species A. simplex is widespread in Svalbard. In the practical part, I dealt with methods that helped me to identify the studied specimens. I observed the trematode tegumental surface with aid of a scanning electrom microscope (JEOL JSM-7401F). The trematode internal organs were stained with Mayer-Schuberg carmine, which allowed me to observe and draw the mounted specimens using a light microscope (Olympus BX51) equipped with a drawing attachment. Furthermore, for molecular analysis, the DNA was isolated using the commercial Exgene Tissue SV mini kit (GeneAll). The isolated DNA (the gene for the large ribosomal subunit, 28S rRNA) was amplified by PCR, the obtained PCR products were sequenced on an automated sequencer (ABI Prism 3130xl or 3730xl, by SEQme). The newly acquired sequences (three in total) were aligned in the program Geneious 8.0.5with sequences available from GenBank (64 sequences). Phylogenetic analysis of the species relationships within the family Aporocotylidae was performed using the Maximum Likelihood method with TPM2u + F + G4 used as the best model. Aporocotyle simplex falls into a separate branch together with A. michaudi, from which however, it differs substantially by its morphology (distribution of tegumental spines on body and their number in the clusters, number of testes, ratio of esophagus length to body length) and geographical distribution (A. michaudi occurs in the South Atlantic Ocean).
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Influence of bird schistosome Trichobilharzia regenti on haemocyte activity of lymnaeid snails
Skála, Vladimír
Gastropod molluscs are naturally exposed to various pathogens such as bacteria, or multicellular parasites that include digenetic trematodes (digeneans) which develop in snails. To combat these pathogens gastropods have evolved a sophisticated internal defence system that is composed of humoral and cellular arms. Lectins are probably the most important humoral components, whereas haemocytes represent the main effector cells. Immunity is one of the important factors determining compatibility/non-compatibility of gastropods and pathogens (particularly snails and trematodes). The introductory part of this thesis includes a review of literature focused on the components of the gastropod immune system and their reactions against pathogens represented by bacteria and digeneans. Additionally, selected immunomodulations caused by compatible digenean species are reviewed. Experimental work (presented in publications) focused mainly on the influence of the bird schistosome Trichobilharzia regenti on haemocyte activities of two lymnaeid snail species, Radix lagotis and Lymnaea stagnalis that are susceptible or refractory to the parasite, respectively. This schistosome parasite causes neuromotor disorders in specific definitive hosts (waterfowl), but it also causes cercarial dermatitis in accidental hosts...
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