The Wall Street Journal writes, "China's securities regulator said Friday that it has called on the nation's securities brokers and fund managers to help stabilize the stock market after a steep selloff in recent weeks. In meetings with officials from the securities industry, a senior official with the China Securities Regulatory Commission also called for stepped-up supervision over margin trading in an effort to limit market risk, the regulator said. Margin trading, which allows investors to buy shares with borrowed funds, has been a factor in China's massive stock-market run-up and subsequent dramatic drop."