Malaria merozoite surface protein 1 (MSP1) is cleaved in an essential step during erythrocyte invasion. The responses of children to natural malaria infection included antibodies that inhibit this cleavage and others that block the binding of these inhibitory antibodies. There was no correlation between the titer of the antibody to the 19-kDa fragment of MSP1 and its inhibitory activity. These findings have implications for the design of MSP1-based vaccines.

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Thrombocytopaenia, or platelet aggregation, is a serious complication of African trypanosomiasis. The biochemical basis is not clearly known. Proteases are known potent inducers of blood coagulation and platelet aggregation, and unknown factors released by Trypanosoma brucei have been shown to induce platelet aggregation. In attempts to define the biochemical mechanisms involved in thrombocytopaenia we purified and characterised a major proteolytic enzyme released extracellularly by T. brucei. Actively motile trypanosomes released proteins into the medium (phosphate saline/glucose, pH 8.0) in which the organisms were incubated in vitro. The M(r) of the released polypeptides ranged from 15 to > 200 kDa, amongst which are proteases. One of the major protein bands, a 250 kDa protease, was purified to homogeneity by ammonium sulfate precipitation followed by diethylaminoethyl (DEAE)-cellulose chromatography and Sephacryl S-300 gel filtration. The protease migrated as a single band of 63 kDa upon electrophoresis in both denaturing and non-denaturing gel co-polymerised with gelatin. The enzyme was strongly active against Z-ARR-AFC peptide substrate, with a pH optimum of 7.0. The proteolytic activity was enhanced by dithiothreitol and inhibited by E-64, leupeptin, TPCK and antipain. The released proteolytic enzyme is putatively identified as a cathepsin B-like cysteine protease.

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Background:The most common cause of anemia is a deficiency of iron; but it may also be caused by deficiencies of folates, vitamin B 12 and protein. Some anemias are not caused by nutritional factors, but by congenital factors and parasitic diseases such as malaria. This study attempted to estimate the prevalence of anemia among pre-school and school-aged children in two rural areas of Odogbolu Local government area, and to determine whether its cause was nutritional or could be attributed to malaria. Methods: A total of 177 children between the ages of 2 and 11 years were included in the study. Children were examined for malaria parasites by microscopy. The World Health Organization (WHO) age-adjusted cut-off for hemoglobin and hematocrit were used to classify anemia. An enzyme linked immunosorbent assay for serum ferritin was compared with standard methods of determining iron deficiency. Under-nutrition (stunting, wasting and underweight) was classified according to the National Centre for Health Statistics standards. Values below  -2SD were defined as mild-moderate under-nutrition, and those below  -3SD as severe malnutrition. Results: Most of the children were anemic, 87.1%, having PCV values below the 32% cut-off and 95% with hemoglobin levels lower than the 11g/dl, although parasite prevalence and density were low. Malnutrition was patent; 36% of the children were stunted, 18.3% wasted and 44.2% underweight. Serum ferritin was more sensitive than PCV in detecting anemic children. Although anemia was higher in boys and preschoolers compared to girls and school aged children, the difference was significant only in preschoolers (P = .004). Anaemia was also significantly higher in Irawo village school than in Iloti (P = .0001) Conclusion: The anemia detected in this population may be due more to under-nutrition than to malaria. Key words: Anaemia, nutrition, childrenRésumé Introduction: La cause la plus fréquente de l'anémie est une carence en fer, mais elle peut aussi être causée par des carence en folates, vitamine B12 et de protéines. Certaines anémies ne sont pas causées par des facteurs nutritionnels, mais par les facteurs congénitales et les maladies parasitaires telles que le paludisme. Cette étude est pour but d'estimer la prévalence de l'anémie chez les préscolaires et les enfants d'âge scolaire dans deux zones rurales de l'administration locale d'Odogbolu, et de déterminer si sa cause est nutritionnel ou pouvaient être attribués à la malaria. Méthodes: Un total de 117 enfants âgés entre 2 et 11 ans ont été inclus dans l'étude. Des enfants ont été étudiés pour les parasites du paludisme par microscopie. L'Organisation Mondiale de la Santé (OMS), l'âge corrigé de coupure de l'hémoglobine et l'hématocrites ont été utilisés pour classer l'anémie. L'anémie. Une enzyme ayant rapport avec immunosorben assay pour la ferritinemie a été Nutritional anaemia and malaria in children. Anumudu C et al. Page | 12 comparée avec les méthodes standard de la détermination de la carence en fer. La sous-alime...