In normal human serum (NHS), axenic promastigotes of Crithidia, Phytomonas, and Leishmania trigger complement activation, and from 1.2 to 1.8 x 10(5) C3 molecules are deposited per promastigote within 2.5 min. In Leishmania, promastigote C3 binding capacity remains constant during in vitro metacyclogenesis. C3 deposition on promastigotes activated through the classical complement pathway reache...

The leishmanioses, vector-borne diseases caused by the trypanosomatid protozoan Leishmania, are transmitted to susceptible mammals by infected phlebotomine sand flies that inoculate promastigotes into hemorrhagic pools created in host skin. We assumed that promastigotes are delivered to a blood pool, and analyzed early promastigote interactions (0-5 min) with host components, which lead to para...

Transmission of leishmaniasis is effected by a specific developmental stage, the metacyclic promastigote. The precursors of metacyclic promastigotes were a distinct subpopulation of parasites, identified for the first time as a new stage in the life-cycle and named leptomonad promastigotes. Microdissection of infected sandflies into 4 midgut regions and foregut allowed precursor-product relatio...

Artemisinin and its derivatives are very important new class of antimalarial drugs. One of the most important artemisinin derivatives is artemether. The antiparasitic activity of artemether as a derivative of artemisinin is related to endoperoxide bridge in its structure. The aim of this study was the evaluation of antileishmanial effect of artemether, with more focus on its apoptotic effect. I...

Artemisinin and its derivatives are very important new class of antimalarial drugs. One of the most important artemisinin derivatives is artemether. The antiparasitic activity of artemether as a derivative of artemisinin is related to endoperoxide bridge in its structure. The aim of this study was the evaluation of antileishmanial effect of artemether, with more focus on its apoptotic effect. I...

visceral leishmanisasis is endemic and zoonotic in several foci in ardabil province, north west of iran. the main objective of this study was to determine the natural promastigote infection of sand-flies in active seasons, during 1991-1995. sand-flies were caught by sticky traps, aspirator and cdc light traps from indoors and outdoors. altogether 2659 sandflies were dissected and identified. th...

Leishmania chagasi, the cause of South American visceral leishmaniasis, requires iron for its growth. However, the extent to which different iron sources can be utilized by the parasite is not known. To address this question, we studied acquisition of iron from lactoferrin and transferrin by the extracellular promastigote form of L. chagasi during growth in vitro. A promastigote growth medium b...

Artemisinin and its derivatives are very important new class of antimalarial drugs. One of the most important artemisinin derivatives is artemether. The antiparasitic activity of artemether as a derivative of artemisinin is related to endoperoxide bridge in its structure. The aim of this study was the evaluation of antileishmanial effect of artemether, with more focus on its apoptotic effect. I...