Pathology and Pathogenesis: The genetics of rosette formation in Plasmodium falciparum has been investigated in a paper starting on page 371 in which the authors were able to select and maintain in vitro rosette-positive and -negative clones, providing a methodology to study the molecular basis of this important phenomenon. The continued importance of animal models in the study of pathogenesis of human disease is demonstrated in a paper starting on page 382 in which Canadian colleagues have shown a clear relationship between disaccharidase activity and resistance to infection by Giardia muris in selected mouse strains. The third paper in this section (see page 391) provides insights into an animal model for the study of cerebral malaria. This P. coatneyi/Macaca mulatta system will give investigators an opportunity for controlled studies on this most serious clinical manifestation of human malaria.

Clinical Studies: Taiwanese investigators have studied 125 cases of amebic liver abscess and provide important insights on prognostic factors that can be indicators of severe disease requiring more radical therapeutic intervention (see page 398).