Further developments of -unsaturated -ketoesters as versatile synthons in asymmetric catalysis.

-Unsaturated -ketoesters prove to be versatile organic synthons participating in diverse catalytic asymmetric transformations with the breathtaking development of organo-catalysis, new catalytic systems including ingenious chiral ligands as well as Lewis acid cations. The highly efficient creation of stereogenic centers with excellent enantioselectivity is not a surprise, but owes to the bidentate coordination of its unique 1,2-dicarbonyl motif to artful chiral messenger, establishing a rigid system for the precise chiral-identification of the attack. In the past five years, various reaction modes of -unsaturated -ketoesters have been developed, involving their multiple reaction sites, such as the carbon-carbon double bond (C=C), the carbonyl group (C=O), the entire C=C-C=O fragment, and the ester group.

Vascular endothelial growth factor (VEGF) gene polymorphisms and breast cancer risk in a Chinese population.

Vascular endothelial growth factor (VEGF) is a potent regulator of angiogenesis and thereby involved in the development and progression of solid tumours. Associations between three VEGF gene polymorphisms (-634 G/C, +936 C/T, and +1612 G/A) and breast cancer risk have been extensively studied, but the currently available results are inconclusive. Our aim was to investigate associations between three VEGF gene polymorphisms and breast cancer risk in Chinese Han patients.

Aspirin use and breast cancer risk: a meta-analysis.

Animal and in vitro studies suggest that the use of aspirin may be associated with reduced risk for breast cancer, but results from these studies of the association have been inconsistent. The objective of this meta-analysis was to quantitatively summarize the current evidence for such a relationship. We searched MEDLINE for studies of aspirin use and breast cancer risk that were published in any language, from January 1, 1966, to July 1, 2011.