Comparative performance of the Mbita trap, CDC light trap and the human landing catch in the sampling of Anopheles arabiensis, An. funestus and culicine species in a rice irrigation in western Kenya

Background

IL-1β and IL-1RA levels are higher in the serum of cerebral malaria patients than in patients with mild malaria. Recently, the level of IL1B expression was reported to be influenced by a polymorphism in the promoter of IL1, IL1B -31C>T.

Methods

To examine whether polymorphisms in IL1B and IL1RA influence the susceptibility to cerebral malaria, IL1B -31C>T, IL1B 3953C>T, and IL1RA variable number of tandem repeat (VNTR) were analysed in 312 Thai patients with malaria (109 cerebral malaria and 203 mild malaria patients).

Results

In this population, IL1B -31C>T and IL1RA VNTRwere detected, while IL1B 3953C>T (i.e., IL1B 3953T) was not observed in the polymorphism screening for 32 patients. Further analyses for IL1B -31C>T and IL1RA VNTR in 110 cerebral malaria and 206 mild malaria patients showed no significant association of these polymorphisms with cerebral malaria.

Conclusion

The present results suggest that IL1B -31C>T and IL1RA VNTR polymorphisms do not play a crucial role in susceptibility or resistance to cerebral malaria.     

The isolation and some properties of a lectin (Haemagglutinin) from Cucurbita phloem exudate

The occurrence of high haemagglutinating (lectin) activity in phloem exudate from three cucurbit species is reported. The protein responsible for this lectin activity in Cucurbita maxima Duch. has been isolated by cation exchange chromatography on Sepharose and identified by gel electrophoresis. The lectin showed agglutinating activity at concentrations as low as 0.1 g/ml. No sugar, including those transported in the phloem of these species, interacted with agglutination. The lectin could not be extracted from cucurbit seed, but appeared in 5-day old seedlings. The possible role of a lectin in the sieve element is discussed.     

Heterogeneity in phloem protein complements from different species

Protein subunits present in phloem exudate from 17 cultivars, 5 species and 3 genera of the Cucurbitaceae have been fractionated by SDS-gel electrophoresis. The degree of difference in the phloem protein patterns appears to reflect the taxonomic relationships of the plants: there were major differences among genera, significant differences and similarities among species, and relatively few differences among cultivars of a single species. A representative of another family (Acer pseudoplatanus; Aceraceae) provided a completely different electrophoretic pattern. Each plant displayed a consistent protein pattern, irrespective of the organ from which exudate was obtained or the age and physiological status of the plant. Neither complete etiolation nor transition to the flowering phase effected any change in phloem proteins. The differences in phloem proteins between plants and the unusual properties of major subunits from different protein complements, render improbable many of the present ideas concerning the origin and function of P-protein.     

Radioautographic analysis of the distribution of label from h-indoleacetic Acid supplied to isolated coleus internodes

Isolated fifth internodes of Coleus blumei Benth. were supplied with ³H-IAA at their apical ends. Microradioautography, using thin sections (0.25-0.5 microns) of Epon embedded tissue and liquid emulsion techniques, revealed extremely specific localization of the acetone-insoluble derivatives of IAA. Changes in the patterns of labeling were followed over periods of 3, 24, and 48 hr at various distances from the source of applied auxin. Progressively basipetal labeling of the cell walls of the youngest xylem elements was evident with time. At the end of 24 hr the label was detected also within the cytoplasm or slime of phloem elements. After 24 to 48 hr, labeling of plastids was evident. The results suggest a continued incorporation of IAA derivatives into cell wall precursors.     

Phenylglycine as a novel P2 scaffold in hepatitis C virus NS3 protease inhibitors

Molecular modeling and inhibitory potencies of tetrapeptide protease inhibitors of HCV NS3 proposed phenylglycine as a new promising P2 residue. The results suggest that phenylglycine might be capable of interacting with the NS3 (protease-helicase/NTPase) in ways not possible for the common P2 proline-based inhibitors. Thus, a series of tripeptides, both linear and macrocyclic, based on p-hydroxy-phenylglycine in the P2 position were prepared and their inhibitory effect determined. When the p-hydroxy group was replaced by methoxy, isoquinolin-, or quinolinyloxy functions, inhibitors with improved potencies were obtained. The P2 phenylglycine-based inhibitors were further optimized by C-terminal extension to acyl sulfonamides and by P1-P3 cyclization, which gave products with inhibition constants in the nanomolar range ( approximately 75nM).     

MalariaSphere: A greenhouse-enclosed simulation of a natural Anopheles gambiae (Diptera: Culicidae) ecosystem in western Kenya

Background  

The development and implementation of innovative vector control strategies for malaria control in Africa requires in-depth ecological studies in contained semi-field environments. This particularly applies to the development and release of genetically-engineered vectors that are refractory to Plasmodium infection. Here we describe a modified greenhouse, designed to simulate a natural Anopheles gambiae Giles ecosystem, and the first successful trials to complete the life-cycle of this mosquito vector therein.     

Calcium-binding protein in sieve tube exudate

A calcium-binding macromolecule, with an estimated molecular weight greater than 100,000, was detected in phloem exudate from Cucurbita maxima and related species. The macromolecule was a component of sieve tube sap, rather than a contaminant leached from cell walls or cut parenchyma cells during exudate collection. The protein nature of this macromolecule was deduced from its size, lability, susceptibility to proteolytic digestion, and by the dependence of calcium-binding activity on thiol-protecting agents. This protein is distinct from the major proteins of exudate and does not appear to be related to calmodulin.Abbreviations SDS-PAGE sodium dodecyl sulphate polyacrylamide gel electrophoresis - CBP calcium-binding protein     

Inheritance of Variegation

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