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Interaction between tapeworm infection and heavy metals accumulation in the host
Magdálek, Jan ; Jankovská, Ivana (advisor) ; Ivana, Ivana (referee)
Heavy metals in living organisms occur in trace amounts. While zinc is an essential element wich is indispensable for many physiological processes, cadmium in body acts
as atissue toxin, that can cause oxidative stress and contribute to cancer development. Recent studies suggest that some species of tapeworms (Cestoda) and Acantocephala are able
to absorb in their tissue higher quantity of heavy metals in comparsion with their hosts. Moreover it was observed that In connection with the increased accumulation of heavy metals in the tissue of tapeworm was decreased amounts of these metals in the organs of the host. The aim of this thesis was to investigate whether the rat tapevorm (Hymenolepis diminuta) causes a decrease in the concentration of Cd and Zn in the organs of rats. A total of 24 Wistar rats (Rattus norvegicus) were divided into 4 groups (n=6). Groups PT and 0P take increased doses of kadmium (3,0 mg/week) and zinc (235,7 mg/week) for six weeks. This increased intake was achieved by adding Arabidopis halleri to feed. After six weeks rats were killed and concentrations in their tissues (bone, muscle, testes, spleen, intestine, liver kidney) were analyzed. Subsequent statistical tests confirmed lower levels of Cd and Zn in some organs
of rats infected with tapeworm compared to rats without infection. For example
in kidney, liver ant intestine of infected rats was detected 2,9; 2,5 and 1,8 times lower concentrations of cadmium and zinc in comparsion with uninfected rats. Tapeworm absorbed 1695 time higher amount of kadmium compared to the host muscle. The zinc content was lower in all organs (except spleen and testes) of infected rats in comparsion to uninfected.
In kidney, liver and intestine of infected rats was 1,2; 1,25 and 1,4 times lower average concentration of zinc in comparsion with uninfected rats. The tape worm absorb higher concentration of zinc compared to all organs of the host.
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Revision of tapeworms of family Diphyllobothriidae (Eucestoda: Solenophoridae) from the monitor lizards
VLNOVÁ, Ivana
Diphyllobothriidean tapeworms are well-known parasites of mammals including man, but species parasiting in reptiles are much less known. These tapeworms belong to three genera (Bothridium, Duthiersia, Scyphocephalus) of the family Solenophoridae and are characterized by their unique scolex morphology. They occur in the intestine of varanid lizards and snakes. All three genera are known from Asia, two from Africa (Bothridium and Duthiersia) and one from Australia and South America (Bothridium). Individual genera are well characterised, but species composition of these genera is not well understood. This study surveyed available literary data on the genera Duthiersia and Scyphocephalus and provides new information based on new collected material from Africa and Southeast Asia and material deposited in helminthological collections.
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Morphological analysis of the tapeworms eggs of the order Diphyllobothriidea
LEŠTINOVÁ, Kateřina
The order Diphyllobothriidea is a unique group of tapeworms in terms of the wide spectrum of definitive hosts involving all groups of tetrapods including man. They are almost globally distributed in both freshwater and marine ecosystems, but there are also terrestrial species. It is very difficult to identify species of diphyllobothriid cestodes to the species level. Morphology of the eggs might represent a new method in the differential diagnosis of these parasites. Besides the size and shape of the eggs, the structure of egg surface might play a significant role in the determination of different taxa. For the analysis of these characteristics Scanning Electron Microscopy (SEM) was used. Experimental infections in hamsters and man were done.
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Manipulation hypothesis: critical review of published works on parasitic invertebrates
TRÁVNÍČKOVÁ, Jana
The manipulation hypothesis has attracted many researchers, and at present it seems to be documented fora wide range of parasites. However, in the last thirty years, numerous parasites have been revealed that, in fact, cannot manipulated with their host morphology, behaviour, and/or habitat preference, unlike conclusions of the previous studies. The major purpose of this study is to test critically the plausibility of the hypothesis about parasitic manipulation, based on metaanalysis of 55 papers concerning four helminth taxa, namely, Acanthocephala, Cestoda, Trematoda, and Nematomorpha.
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Tapeworms of family Gryporhynchidae from Africa
HAASOVÁ, Ivana
Morphological-taxonomical study of gryporhynchid cestodes from Africa is presented. New material from Kenya, Senegal and Sudan was studied and we belong to 17 species in 8 orders - Amirthalingamia macracantha (Joyeux et Baer, 1935) Bray, 1974; Anomotaenia riccii (Fuhrmann et Baer, 1943) Baer et Bona, 1960; Cyclustera magna (Baer, 1959) Bona, 1975; Cyclustera sp.; Dendrouterina macrosphincter (Fuhrmann, 1909) Baer et Bona, 1960; Neogryporhynchus sp.; Paradilepis lloydi (Southwell, 1926) Spasski, 1954; Paradilepis maleki (Khalil, 1961); Paradilepis urceina Bona, 1975; Paradilepis urceus (Wedl, 1855) Joyeux et Baer, 1950; Parvitaenia macrocoleo Bona, 1975; Parvitaenia macropeos (Wedl, 1855) Baer et Bona, 1960; Parvitaenia megascolecina Bona, 1975; Parvitaenia purpurea Johri, 1959; Parvitaenia samfyia Mettrick, 1967; Valipora ardeolae (Singh, 1952) Baer et Bona, 1960 and Valipora mutabilis (Linton, 1927). Known larval stages and adults from Africa are presented in review of species.
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