Origin of lead in andean calc-alkaline lavas, southern peru

Lead isotope data from Quaternary andesitic lavas of the Arequipa and Barroso groups of southern Peru and from regional Precambrian granulitic gneisses reveal a lead component in the lavas from the gneisses. The lava leads can be accounted for by two-component mixtures of lead from mantle and lower crustal sources, although the mixing process need not have occurred in the lower crust.     

Harnessing chaperones to generate small-molecule inhibitors of amyloid beta aggregation

Protein aggregation is involved in the pathogenesis of neurodegenerative diseases and hence is considered an attractive target for therapeutic intervention. However, protein-protein interactions are exceedingly difficult to inhibit. Small molecules lack sufficient steric bulk to prevent interactions between large peptide surfaces. To yield potent inhibitors of beta-amyloid (Abeta) aggregation, we synthesized small molecules that increase their steric bulk by binding to chaperones but also have a moiety available for interaction with Abeta. This strategy yields potent inhibitors of Abeta aggregation and could lead to therapeutics for Alzheimer's disease and other forms of neurodegeneration.