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Leishmaniasis in domestic and wild animals
Ferencová, Blanka ; Kolářová, Iva (advisor) ; Spitzová, Tatiana (referee)
Leishmaniasis is an infectious disease affecting a wide range of vertebrates, including humans. Leishmania donovani is the causative agent of its most severe form - visceral leishmaniasis. So far animal reservoir has not been proven in the life cycle of this parasite and a man is regarded as the only source of infection. However, zoonotic transmission is demonstrated in the species Leishmania infantum, which together with L. donovani and L. archibaldi belongs into L. donovani complex. A lot of domestic and wild animals living near human dwellings are therefore tested for the presence of Leishmania DNA or anti-Leishmania antibodies, hoping to uncover reservoir host in the life cycle of L. donovani. Sensitivity and specificity of the methods significantly affects the results of undertaken studies. The animals play a significant role in the epidemiology of the disease also as a significant blood source for the vectors. Understanding the ecological interactions between parasite, vector, man, domestic and wild animals could lead to more effective transmission control, thus reducing incidence of leishmaniasis in endemic foci. Key words: Leishmania donovani, visceral leishmaniasis, reservoir, domestic animals, wild animals
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Host antibody response to sand fly saliva
Pohanková, Lucia ; Kolářová, Iva (advisor) ; Kopecký, Jan (referee)
Leishmaniasis is protozoan diseases, which is transport into the host during the feeding of sand fly. During the feeding of infected sand flies not only the leishmania but also the sand fly saliva are inoculated into the hosts. Sand fly saliva can strongly affect the response of the immune system. If the host hadn't met sand fly saliva yet, the course of infection is usually worse. In cutaneous leishmaniasis, the lesions developed early, being more destructive and perstiting longer, if not healed. The hosts living in endemic areas of leishmaniasis and the vector hosts are often exposed to feeding uninfected sand flies. To hosts are repeatedly inoculated the sand fly saliva antigen and induced specific cellular and antibody responses. Cellular and antibody responses are different for different hosts, attempts were made most frequently in murine and canine models. In humans, as host sis it difficult to monitor development leishamnia infectipon after previous exposure, that's why in humans mainly it is monitors the levels of antibodies, according to which we can determine the extent of sand fly bited and the risk of transmission of leishmaniasis. The specifity of immune responses against sand fly saliva is important for the testing new type of controlling and healing programs against sand fly and...
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The role of Sergentomyia schwetzi in visceral leishmaniasis foci in Ethiopia and canine leishmaniasis in Romania
Polanská, Nikola ; Kolářová, Iva (advisor) ; Kodym, Petr (referee)
Visceral Leishmaniasis is a disease caused by protozoan pathogen of Leishmania donovani complex (Kinetoplastida). There are some of the worst recorded outbreaks of the disease in the countries of East Africa. In the Old world the Phlebotominae sand flies of the genus Phlebotomus are vectors of Leishmania parasites, the causative agent of leishmaniasis that can affect vertebrates, including humans and veterinary important animals, while the so-called reptilian Leishmania are transmitted by the genus Sergentomyia. In the first part of this master thesis we present a summary of the results of studies and experiments focused on antibody response to saliva of the species Sergentomyia schwetzi of domestic animals in northern Ethiopia, that we could clarify the question whether sand flies of this genus take blood on warm-blooded animals. Using serological tests have confirmed the hypothesis that the species S. schwetzi, preferentially blood-taking on the reptiles, also takes blood on the warm-blooded vertebrates and might play a role in the transmission and mammalian Leishmania. In the second part of this thesis, we focus on the detection of protozoan Leishmania infantum (complex of Le. donovani) in dogs from Romania. We use specific primers against the kinetoplast DNA of Leishmania sp. but in no sample...
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Anticoagulation factors of haematophagous parasites
Skipalová, Karolína ; Mikeš, Libor (advisor) ; Kolářová, Iva (referee)
2. Abstract Presence of antihaemostasis molekule is essential for the successful reception of food organisms that feed on blood. They are vasodilators, anticoagulant molecules and apyrases that break into the host hemostasis, thus blocking the whole process. This work summarizes all available information about the anticoagulant factors of haematophagous parasites. The blood sucking groups of helminths, arthropods and leeches is particularly inhibitors of serine proteases, which have their inhibitory aktivity directed primarily against thrombin and factor Xa. These are two key factors in the coagulation cascade. Factor X is the first member, where it sets the intrinsic and extrinsic coagulation pathways. At the same time it arises due to the aktive form of the protein thrombin, which is responsible for the conversion of soluble fibrinogen to insoluble fibrin, which stops bleeding. In addition to these two factors are inhibited of other members of the cascade. For example the inhibition of komplex factor VII and TF, which has been described in ticks and hookworms. Anticoagulation factors play a crucial role in the transmission of pathogens by blood from the vector into the host. The longer the blood is a liquid, the greater the chance of transmission of the pathogen.
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Macrophages in leishmania - sand fly - host interaction
Kratochvílová, Tereza ; Kolářová, Iva (advisor) ; Fialová, Anna (referee)
Sand flies (order Diptera) are vectors of Leishmania parasites (Trypanosomatida), which are inoculated into the host skin together with the vector saliva. Sand fly saliva plays the important role in the Leishmania transmission; in naive host it supresses the host immune response assisting Leishmania to establish the infection, while in repeatedly bitten host it elicits a protective immune response. The submitted thesis focuses on the effect of sand fly saliva on macrophages, the key cells in the infection control. In the first part of the thesis we established a laboratory model L. major - P. papatasi - Balb/c to describe the protective effect of saliva immunization on Leishmania infection development. Immunized mice were protected against Leishmania infection which was reflected in the ear lesion size, parasite load in the ear dermis and draining lymph nodes but also in cytokine production. On the contrary, produced lower amount of nitric oxide, while arginase activity was comparable with nonimmunized group. The IgG antibodies against saliva served as a marker of exposure to sandflies while IgG antibodies against Leishmania antigens served as a marker of infection severity. The experiments were aimed on the possibility of cross-protectivity in Balb/c mice against L. major between closely related...
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Immunity in hosts repeatedly exposed to sand fies and the effect on pathogen transmission
Pohanková, Lucia ; Kolářová, Iva (advisor) ; Fialová, Anna (referee)
6 Abstrakt During the feeding of infected sand flies are inoculate into the host also sand fly saliva, which can strongly modulate the response of the immune system. If the host is naive, the course of infection is usually worse. In cutaneous leishmaniasis, the lesions developed early, are more destructive and persist longer. The hosts living in endemic areas of leishamniasis and their vector hosts are often exposed to feeding uninfected sand flies. For host are the saliva antigenic and induces specific cellular and antibody responses. This responses induce the protection against leishmania infection and differ for different hosts, attempts were made most frequently in murine and canine models. In humans, as hosts is difficult to monitor developments leishmania infection after previous exposure, because in humans mainly monitors the levels of antibodies, by which we can determine the degree of sand fly bites and the risk of transmission of leishmaniasis. Keywords: Lutzomyia, Phlebotomus, DTH, antibody, IgG,
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Macrophages and nitric oxide in leishmania - sandfly - host interactions
Kratochvílová, Tereza ; Fialová, Anna (referee) ; Kolářová, Iva (advisor)
Leishmania reside fagolysosome of macrophages immediately after their entry to host where they multiply and consequently infect other macrophages or eventually other cells. A synthesis of a reactive reactant of oxygen and nitrogen is one of the mechanisms that some mammal cells are equipped with and that also contributes to eradication of leishmania. Nitric oxide rising during a metabolic change of L-arginine under the catalysis of NO synthase is of a large importance. Beyond cytotoxic function, nitric oxide is involved in signalling pathways for a neurotransmission (nNOS) and vasorelaxation (eNOS). Not all types of macrophages have ability to produce NO (iNOS). It is a heterogeneous group differing in immunological function and also in physiology. A group of classical activated macrophages represents an effective APC capable of efficient killing of intracellular pathogens. In addition to NO, they also secrete an inflammatory cytokines, which evolve an immune reaction towards to Th1. Contrary to this, a group of alternative activated macrophages is not capable of any efficient antigen presentation and nitric oxide production but produces L-ornithine, which is a precursor of polyamines, which leishmania utilizes for its own intracellular growth. For the mouse model, status of resistance and/or...
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