Good buying was observed in banking index (bankex), capital goods,oil and gas and auto sectors, while selling pressure was seen in IT and healthcare sectors. The 30-scrip sensitive index (Sensex) of the S&P Bombay Stock Exchange (BSE), which opened at 21,539.44 points, was trading at 21,727.74 points in the pre-noon session, up 213.87 points or 0.99 percent from the previous day's close at 21,513.87 points.