**MERCK& CO INC, $45.95, down 2 pct. **TITAN PHARMACEUTICALS INC, $0.46, down 73 pct. **NEUTRAL TANDEM INC, $4.57, up 53 pct.
Stocks fell as the broadest measure of U.S. economic growth fell short of expectations in the first quarter and Amazon.com gave a disappointing outlook. **CHEVRON CORP, $120.06, up 1.3 pct. **AMAZON.COM INC, $255.52, down 7 pct.
April 25- Extreme Networks Inc:. *Appoints cHarles W. Berger as its president and Chief Executive Officer;. *Says Berger will be replacing Oscar Rodriguez who has resigned, effective.