Malaria parasite Subject

Most of the work on membrane transport with malaria parasites prior to 1990 concerned itself with studies of bird, murine and monkey plasmodia (Plasmodium lophurae, P. berghei and P. knowlesi) and this was summarized some 20 years ago (Sherman, 1979,1988). With the successful in vitro culture of P. falciparum, membrane-transport phenomena of malaria-infected red cells and free parasites have concerned themselves principally with this species and this too has been the subject of periodic review (e.g. see Kirk s tour de force, 2001). 

In the first LDMS-based detection of malaria in human subjects (unpublished), lOOpl P. falciparum or P. v/vax-infected blood samples, grouped into three different parasitemia ranges—low (10-150 parasites/pl), mid (2 x 103 parasites/pl), and high (25 x 103-60 x 103 parasites/pl)—have been examined using both sample preparation protocols. Parasitemia levels in these samples were previously determined independently for each sample by optical microscopy examination of blood smears. The LDMS data clearly indicate that... 

A number of studies have noted that, in areas where malaria is endemic, riboflavin-deficient subjects are relatively resistant and have a lower parasite burden than adequately nourished subjects. Dietary deficiency of riboflavin, hypothyroidism, which induces functional riboflavin deficiency by lowering the synthesis of flavokinase (Section 7.2.4), or the administration of chlor-promazine, which inhibits flavokinase and can cause functional riboflavin deficiency (Section 7.4.4), all inhibit the growth of malarial parasites in experimental animals. However, although parasitemia is less in riboflavin deficiency, the course of the disease may be more severe (Dutta et al., 1985 Dutta, 1991 Akompong et al., 2000a, 2000b Shankar, 2000). 

Hogh, B., Petersen, E., Crandall, I., Gottschau, A., and Sherman, I. W. (1994). Immune responses to band 3 neoantigens on Plasmodium falciparum-infected erythrocytes in subjects living in an area of intense malaria transmission are associated with low parasite density and high hematocrit value. Infect. Immun. 62,4362-4366. 

Quartan malaria is caused by infection with P. malariae. Although the mildest form of the disease, it is the most persistent, and relapses may take place years after the primary infection. Indeed, the parasite can produce cases of transfusion-induced malaria in non-immune subjects receiving infected blood. The geographical distribution of P. malariae is similar to that of P. falciparum. 

A number of studies have noted that in areas where malaria is endemic riboflavin-deficient subjects are relatively resistant and have a lower parasite burden than adequately nourished subjects. The biochemical basis of this resistance to malaria in riboflavin deficiency is not known, but two possible mechanisms have been proposed ... 

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