Indian equity benchmarks Sensex and Nifty reversed early gains to trade lower by midday Thursday, reflecting a cautious investor mood amid growing uncertainty surrounding the leadership of the US Federal Reserve and other macroeconomic factors. The Sensex had opened on a stronger note, rising by 119.05 points to touch 82,753.53, while the Nifty advanced 18.7 points to 25,230.75. However, this initial positivity gave way to selling pressure later in the session, dragging the Sensex down to 82,