Oil prices top $50, Asian shares struggle as China sags

By Hideyuki Sano TOKYO (Reuters) - Brent crude oil rose above $50 a barrel for the first time in nearly seven months on Thursday but Asian shares struggled to gain traction, with worries about U.S. interest rates and China's slowing economy keeping investors on the sidelines. While energy stocks outperformed, a slump in mainland China stocks to 2-1/2 month lows dampened any broader interest in riskier assets in Asia, offsetting overnight gains on Wall Street. Oil prices are rising, which would b