|
|
Sauroleishmania-sand fly interactions
Tichá, Lucie ; Volf, Petr (advisor) ; Berriatua Fernández de Larea, Eduardo (referee) ; Shaw, Jeffrey Jon (referee)
Sauroleishmania is a group of less studied parasites that belong to the genus Leishmania (Kinetoplastida: Trypanosomatidae). They circulate between reptile hosts and sand fly vectors (Diptera: Psychodidae). Due to the non-pathogenic character of its species, little is known about their development in reptiles and sand flies. The main objective of this project was to elucidate some missing aspects of Sauroleishmania life cycle. A major part of this thesis aimed to test the susceptibility of various sand fly species to different Sauroleishmania isolates and describe their development in the sand fly intestinal tract. A minor part was devoted to the study of infection in reptiles. First, we investigated the development of Leishmania (Sauroleishmania) tarentolae in three Phlebotomus species. Sand flies were infected through membrane on promastigote suspension and dissected at various time intervals post infection. Leishmania (S.) tarentolae developed in all three species tested and underwent peripylarian type of the development. Moreover, heavy parasite loads were frequently found in Malpighian tubules, which is a unique localization among Leishmania parasites. To summarize the current knowledge on L. (S.) tarentolae, we have also written a review describing the origin, life cycle and application of...
|
|
|
Sauroleishmania: development in the vectors and hosts
Tichá, Lucie ; Volf, Petr (advisor) ; Kodym, Petr (referee)
Leishmania of subgenus Sauroleishmania are parasites of reptiles, most often lizards, and are not pathogenic for humans. Therefore, they are neglected group of pathogens and their life cycle is not well-known. They are transmitted probably by ingestion of infected vector which is usually considered as sand flies of genus Sergentomyia (Diptera: Psychodidae). Sauroleishmania are traditionally denominated in Hypopylaria and it is expected that their development is limited to sand fly hindgut. The main aim of this work is to summarize the present knowledge about Sauroleishmania life cycle and to elucidate some aspects of their development in the vector and host. In the first part of thesis we studied development of four Sauroleishmania species in various sand flies of genera Sergentomyia and Phlebotomus. Late-stage infections of Leishmania (S.) adleri and L. (S.) hoogstraali were found in six and two sand fly species, respectively. Hypopylarian infections of Leishmania (S.) adleri were found in Se. schwetzi, P. papatasi and P. sergenti, while in P. argentipes, P. orientalis and P. duboscqi this Sauroleishmania migrated anteriorly in the midgut (peripylarian development). Similar type of development was observed also in P. argentipes and P. orientalis infected by Leishmania (S.) hoogstraali. Both L....
|
|
|
Identification of bloodmeal sources in phlebotomine sand flies and other bloodfeeding arthropods
Kykalová, Barbora ; Dvořák, Vít (advisor) ; Spitzová, Tatiana (referee)
Hematophagous arthropods that are involved in transmission of many infectious diseases have profound importance in human and veterinary medicine. Bloodmeal identification considerably contributes towards better understanding of vector-borne diseases and vector-host interaction. It reveals epidemiologically significant data on reservoir hosts and degree of anthropophily of studied arthropods. Methods of bloodmeal identification evolved from field observations, serological and DNA-based methods towards protein analyses. Nowadays, the most frequent methods are DNA-based methods but new methods are still being developed. This bachelor thesis summarizes and compares used methods with the primary focus on phlebotomine sand flies, which are involved in transmission of leishmaniases. Key words: sand flies, bloodmeal identification, hematophagous arthropods, analysis
|
|
|
A comparison of the peritrophic matrix in four sand fly species (Diptera: Psychodidae) and its role in the Leishmania development (Kinetoplastida: Trypanosomatidae).
Homola, Miroslav ; Sádlová, Jovana (advisor) ; Hypša, Václav (referee)
anglický Phlebotomine sand flies (Diptera: Psychodidae) are the only proven vectors of Leishmania parasites (Kinetoplastida: Trypanosomatidae). In Nematoceran Diptera, including sand flies, adults produce a type 1 peritrophic matrix (PM) which is secreted in response to the distension of the midgut caused by blood meal. The PM is an acellular envelope composed of chitin fibres and proteins, which protects the midgut epithelium against abrasion and pathogens and improves digestion. In hematophagous insects, the PM also plays a central role in heme detoxification. Female sand flies acquire Leishmania with a bloodmeal and the parasites undergo complicated development in their gut finished by the colonization of the stomodeal valve. The PM is one of the most important barriers in Leishmania development and its role in the vector competence of the S. schwetzi is the main topic of this master thesis. The PM's kinetic and morfology in the S. schwetzi is compared with other three sand fly species which differ in susceptibility to L. donovani. The key role of the PM in S. schwetzi vector competence is finally proved by disrupting the PM using the exogenous chitinase from Beauveria bassiana. Under these artificial conditions, the Leishmania parasites (L. donovani and L. major) are able to exit the PM,...
|
guest ::
