Synthesis and gene transfection efficacies of PEI-cholesterol-based lipopolymers

Nine lipopolymers based on low molecular weight polyethyleneimines (PEI) and cholesterol via an ether linkage between the polymer amine and the cholesterol backbone have been synthesized. Different percentage of cholesterol moieties have been grafted on three types of PEI of molecular weights 800, 1200, and 2000. These lipopolymers were studied for gene transfection activities in HeLa cells. All the lipopolymers were first optimized for enhanced transfection efficacies as coliposomes with DOPE. All lipopolymers are better transfecting agents and highly serum compatible than commercially available PEI-25KDa. Transfection efficacies and serum compatibility of lipopolymers were found to be dependent upon the MW of PEI used for lipopolymer synthesis and percentage of cholesterol grafting on lipopolymers. Cell viability assay showed that PEI-25KDa is highly toxic as compared to all the lipopolymers. Lipopolyplexes were characterized by transmission electron microscopy, which showed the presence of spherical aggregates.     

Natural occurrence of Gibberella fujikuroi and its potential for control of the woolly aphid Ceratovacuna lanigera (Homoptera: Aphididae) in Indian sugarcane plantations

Studies were conducted to determine the natural occurrence of entomopathogenic fungi and their potential for utilisation in biological control of the woolly aphid (Ceratovacuna lanigera Zehntner) in Indian sugarcane plantations. A fungus Gibberella fujikuroi (Sawada) Wr. (Synonym: Fusarium verticillioides (Sacc.) Nirenberg, Synonym: Fusarium moniliforme (Sheld.) emend. Snyd. and Hans.) was found to be a promising biocontrol agent. It was further characterised and its field performance was studied. Reductions of aphid populations up to 60% were observed when the fungus was applied as two sprays at a week interval in the field.     

Coincident isolation of a novel homoisoflavonoid from Resnova humifusa and Eucomis montana (Hyacinthoideae: Hyacinthaceae)

We report on the first phytochemical investigation of a member of the African genus Resnova (Hyacinthoideae: Hyacinthaceae). From the dichloromethane extract of the bulbs of both Resnova humifusa and Eucomis montana (Hyacinthoideae: Hyacinthaceae) a novel 3-benzyl-4-chromanone homoisoflavonoid, 5,6-dimethoxy-7-hydroxy-3-(4′-hydroxybenzyl)-4-chromanone, was isolated. A further 11 known homoisoflavonoids were also identified, the 12 in total presenting a clear biosynthetic sequence. Eight of the 12 compounds found were common to both species.     

Health information for the developing world.

Doctors and other health professionals in developing countries are missing out on relevant information about health. A lot of the information they need is available in the developed countries, and those who have it are happy to share it with them. But transporting information, like food or medicines, from one part of the world to another is not an easy task nor is it the complete answer to the information drought. It is one thing to ferry books and journals from Europe to Africa and another to make relevant information available to the right person at the right time at an affordable cost.     

Structures of HCMV Trimer reveal the basis for receptor recognition and cell entry

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