Search results for "Parasite Physiology"
showing 5 items of 5 documents
Extracellular vesicles from parasitic helminths contain specific excretory/secretory proteins and are internalized in intestinal host cells.
2012
The study of host-parasite interactions has increased considerably in the last decades, with many studies focusing on the identification of parasite molecules (i.e. surface or excretory/secretory proteins (ESP)) as potential targets for new specific treatments and/or diagnostic tools. In parallel, in the last few years there have been significant advances in the field of extracellular vesicles research. Among these vesicles, exosomes of endocytic origin, with a characteristic size ranging from 30-100 nm, carry several atypical secreted proteins in different organisms, including parasitic protozoa. Here, we present experimental evidence for the existence of exosome-like vesicles in parasitic…
Learning can be detrimental for a parasitic wasp
2021
Animals have evolved the capacity to learn, and the conventional view is that learning allows individuals to improve foraging decisions. The parasitoid Telenomus podisi has been shown to parasitize eggs of the exotic stink bug Halyomorpha halys at the same rate as eggs of its coevolved host, Podisus maculiventris, but the parasitoid cannot complete its development in the exotic species. We hypothesized that T. podisi learns to exploit cues from this non-coevolved species, thereby increasing unsuccessful parasitism rates. We conducted bioassays to compare the responses of naïve vs. experienced parasitoids on chemical footprints left by one of the two host species. Both naïve and experienced …
Effect of Multiple Parasitic Infections on the Tolerance to Pollutant Contamination
2012
8 pages; International audience; The horizontally-transmitted acanthocephalan parasite Polymorphus minutus and the vertically-transmitted microsporidian parasite Dictyocoela roeselum have both been shown to influence on the antitoxic responses of mono-infected Gammarus roeseli exposed to cadmium. The present study investigates the effect of this co-infection on the antitoxic defence responses of naturally infected females exposed to cadmium stress. Our results revealed that, depending on the cadmium dose, bi-infection induced only slight, significant increased cell damage in G. roeseli as compared to non-infection. In addition, the antitoxic defence pattern of cadmium-exposed bi-infected ho…
Increased Vascularity in Cervicovaginal Mucosa with Schistosoma haematobium Infection
2011
Background Close to 800 million people in the world are at risk of schistosomiasis, 85 per cent of whom live in Africa. Recent studies have indicated that female genital schistosomiasis might increase the risk of human immunodeficiency virus (HIV) infection. The aim of this study is to quantify and analyse the characteristics of the vasculature surrounding Schistosoma haematobium ova in the female genital mucosa. Methodology/Principal Findings Cervicovaginal biopsies with S. haematobium ova (n = 20) and control biopsies (n = 69) were stained with immunohistochemical blood vessel markers CD31 and von Willebrand Factor (vWF), which stain endothelial cells in capillary buds and established blo…
Biosynthesis of heme O in intraerythrocytic stages of Plasmodium falciparum and potential inhibitors of this pathway
2019
A number of antimalarial drugs interfere with the electron transport chain and heme-related reactions; however, the biosynthesis of heme derivatives in Plasmodium parasites has not been fully elucidated. Here, we characterized the steps that lead to the farnesylation of heme. After the identification of a gene encoding heme O synthase, we identified heme O synthesis in blood stage parasites through the incorporation of radioactive precursors. The presence of heme O synthesis in intraerythrocytic stages of Plasmodium falciparum was confirmed by mass spectrometry. Inabenfide and uniconazole–P appeared to interfere in heme synthesis, accordingly, parasite growth was also affected by the additi…