Drug-eluting Stent Coatings

This paper reviews the development of coronary stents from a polymer scientist\u27s view point, and presents the first results of an interdisciplinary team assembled for the development of new stent systems. Poly(styrene-b-isobutylene-b-styrene) block copolymer (SIBS), a nanostructured thermoplastic elastomer, is used in clinical practice as the drug-eluting polymeric coating on the Taxus coronary stent (trademark of Boston Scientific Co.). Our group has been developing new architectures comprising of arborescent (dendritic) polyisobutylene cores (D_SIBS), which were shown to be as biocompatible as SIBS. ElectroNanospray (Nanocopoeia Inc.™) was used to coat test coupons and coronary stents with selected DSIBS polymers loaded with dexamethasone, a model drug. The surface topology varied from smooth to nanosized particulate coating. This paper will demonstrate how drug release profiles were influenced by both the molecular weight of the polyisobutylene core and spraying conditions of the polymer-drug mixture. Copyright © 2009 John Wiley & Sons, Inc

The Costs of Wrongful-Discharge Laws

We estimate the effects on employment and wages of wrongful-discharge protections adopted by U.S. state courts during the last three decades. We find robust evidence that one wrongful-discharge doctrine, the implied-contract exception, reduced state employment rates by 0.8% to 1.7%. The initial impact is largest for female and less-educated workers (those who change jobs frequently), while the longer-term effect is greater for older and more-educated workers (those most likely to litigate). By contrast, we find no robust employment or wage effects of two other widely recognized wrongful-discharge laws: the public-policy and goodfaith exceptions. Copyright by the President and Fellows of Harvard College and the Massachusetts Institute of Technology.