Mabel O Imbuga

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The concentrations of catechins in a Kenyan tea germplasm collection of 102 accessions were determined by HPLC. Total green leaf catechin concentrations and the ratio of dihydroxylated to trihydroxylated catechins were used to establish genetic differentiation in the germplasm. Upon multivariate analysis, accumulation of the various catechins separated the(More)
The effect of the amino sugard-glucosamine on trypsin in crude midgut homogenates ofGlossina morsitans morsitans was studied in vitro. The results showed that the midgut trypsin was specifically and competitively inhibited byd-Glucosamine. Glucose, fructose, mannose, inositol, galactose, galactosamine,N-acetyl-d-glucosamine, and methyl-α-d-glucosamine were(More)
A blood-meal-induced lectin (agglutinin) with proteolytic activity was isolated from midgut extracts ofGlossina longipennis by a two-step procedure involving anion-exchange chromatography. It is a glycoprotein [native molecular weight (Mr, 61000±3000 da) composed of two noncovalently-linked subunits designated α (Mr, ∼27000 da) and β (Mr, ∼33000 da). The(More)
An in vitro system for studying the transformation of bloodstream forms ofTrypanosoma brucei brucei into procylic (midgut) forms is described. In this system, transformation of the parasites was stimulated byGlossina morsitans morsitans midgut homogenates at 27° C but not at 4° C. The transformation-stimulating capacity was irreversibly destroyed by heating(More)
The properties of a blood-meal-induced lectin (agglutinin) from the midgut ofGlossina morsitans capable of agglutinatingTrypanosoma brucei were studied in vitro. The midgut homogenate from flies that had been fed twice had the highest agglutination activity, followed by that from the once-fed flies and that from the unfed insects. As compared with the(More)
The ability ofTrypanosoma brucei brucei to inhibit trypsin or trypsin-like enzymes in crude midgut homogenates ofGlossina morsitans morsitans was studied in vitro. The isolated parasites caused a concentration-dependent decrease in midgut trypsin activity. Furthermore, trypanosomes lysed by repeated freeze-thawing had a similar effect on trypsin activity.(More)
High primary doses of Trichinella spiralis administered orally to Kenyan baboons (Papio anubis) induced a marked but unpredictable eosinophilia which started 2--3 weeks after infection and persisted as erratic waves for at least 6 months. Low primary oral doses induced no eosinophilia but a later, high challenge gave an accelerated eosinophilic response,(More)
The prevalence of a genetic polymorphism(s) at codon 268 in the cytochrome b gene, which is associated with failure of atovaquone-proguanil treatment, was analyzed in 227 Plasmodium falciparum parasites from western Kenya. The prevalence of the wild-type allele was 63%, and that of the Y268S (denoting a Y-to-S change at position 268) mutant allele was 2%.(More)
Midgut homogenates prepared from Glossina morsitans morsitans, that had previously been fed on different host blood samples, were tested for their abilities to transform bloodstream Trypanosoma brucei into procyclic (midgut) forms in vitro. Compared to rat and goat blood samples, eland blood had the least capacity to support trypanosome transformation,(More)
Genetically determined artemisinin resistance in Plasmodium falciparum has been described in Southeast Asia. The relevance of recently described Kelch 13-propeller mutations for artemisinin resistance in Sub-Saharan Africa parasites is still unknown. Southeast Asia parasites have low genetic diversity compared to Sub-Saharan Africa, where parasites are(More)
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