* Researchers from Abbott Laboratories are conducting trials of a painkiller called ABT-594, which the company says is about 50 times better than morphine in relieving chronic and acute pain yet is not addictive. Abbott scientists had already synthesized ABT-594 for other uses when they learned of the work of National Institutes of Health biologist John Daly, who more than a decade ago discovered the powerful painkilling properties of a substance called epibatidine in the skin of a tiny Ecuadoran tree frog.