Genetic analysis of invasive pneumococcal isolates from children in Ontario, Canada, 2007-2012.

Background: Multilocus sequence typing (MLST) is commonly used to understand the genetic background of invasive pneumococcal disease (IPD) isolates. This study was conducted to identify serotype and genetic change among IPD isolates in Canadian children following vaccine use.

Methods: Clinical isolates collected from children ≤5 years old of Ontario, Canada with IPD during 2007-2012 were characterized with serotyping, multilocus sequence typing and antimicrobial susceptibility testing.

Harmine is a potent antimalarial targeting Hsp90 and synergizes with chloroquine and artemisinin.

Previous studies have shown an antimalarial effect of total alkaloids extracted from leaves of Guiera senegalensis from Mali in West Africa. We independently observed that the beta-carboline alkaloid harmine obtained from a natural product library screen inhibited Plasmodium falciparum heat shock protein 90 (PfHsp90) ATP-binding domain. In this study, we confirmed harmine-PfHsp90-specific affinity using surface plasmon resonance analysis (dissociation constant [K(d)] of 40 μM).

Host immune response in returning travellers infected with malaria.

Background: Clinical observations suggest that Canadian-born (CB) travellers are prone to more severe malaria, characterized by higher parasite density in the blood, and severe symptoms, such as cerebral malaria and renal failure, than foreign-born travellers (FB) from areas of malaria endemicity. It was hypothesized that host cytokine and chemokine responses differ significantly in CB versus FB patients returning with malaria, contributing to the courses of severity. A more detailed understanding of the profiles of cytokines, chemokines, and endothelial activation may be useful in developing biomarkers and novel therapeutic approaches for malaria.