State of Artemisinin and Partner Drug Susceptibility in Clinical Isolates from Colombia.

Delayed parasite clearance time observed in Southeast Asia provided the first evidence of resistance to artemisinins. The ex vivo ring-stage survival assay (RSA) mimics parasite exposure to pharmacologically relevant artemisinin concentrations. Mutations in the C-terminal propeller domain of the putative kelch protein Pf3D7_1343700 (K13) are associated with artemisinin resistance.

Propeller Alleles, Polymorphism, and Drug Effectiveness at Day 3 after Artemether-Lumefantrine Treatment for Plasmodium falciparum Malaria in Colombia, 2014-2015.

High treatment failure rates for malaria have been reported in Colombia for chloroquine, amodiaquine, and sulfadoxine-pyrimethamine. Artemisinin combination therapies were introduced in 2006 in Colombia, where artemether-lumefantrine (AL) is currently used to treat uncomplicated malaria. Artemisinin (ART) resistance was initially observed in Southeast Asia as an increased parasite clearance time, manifesting as a positive thick-blood smear on day 3 after treatment (D3 positivity).

Cytoadhesion to gC1qR through Plasmodium falciparum Erythrocyte Membrane Protein 1 in Severe Malaria.

Cytoadhesion of Plasmodium falciparum infected erythrocytes to gC1qR has been associated with severe malaria, but the parasite ligand involved is currently unknown. To assess if binding to gC1qR is mediated through the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family, we analyzed by static binding assays and qPCR the cytoadhesion and var gene transcriptional profile of 86 P.

Antiplasmodial and Cytotoxic Activity of Raw Plant Extracts as Reported by Knowledgeable Indigenous People of the Amazon Region (Vaupés Medio in Colombia).

The in vitro antiplasmodial activity of 122 raw extracts prepared in ethanol and water from 35 medicinal plants reported by the Cubeo indigenous village of the Amazon region (Vaupés Medio in Colombia) was evaluated for efficacy against 3D7 (sensitive to chloroquine) and FCR-3 (resistant to chloroquine) Plasmodium falciparum strains. Five percent of these extracts presented a significant antiplasmodial activity (< 5 µg/mL) and 83 % of them were not cytotoxic. These findings highlight the importance of investigating traditional medicinal plants implemented by these ancestral communities of the Amazon region as well as their potential to become a source of new drugs against malaria.

Adherence to human lung microvascular endothelial cells (HMVEC-L) of Plasmodium vivax isolates from Colombia.

Background: For years Plasmodium vivax has been considered the cause of benign malaria. Nevertheless, it has been observed that this parasite can produce a severe disease comparable to Plasmodium falciparum. It has been suggested that some physiopathogenic processes might be shared by these two species, such as cytoadherence.