FoxHollow Technologies

( FOXH) surged after saying

Merck

(MRK) - Get Report

would buy an 11% stake in the device maker. FoxHollow was up $5.80, or 21.3%, to $33.05.

Primedia

( PRM) gained after the New York-based media company sold the assets of the Crafts Group for about $132 million in cash. Shares of Primedia added 13 cents, or 8.6%, to $1.64.

MarkWest Hydrocarbon

( MWP) gained after the Englewood, Colo.-based energy company was upgraded by Lehman Brothers to overweight from equal-weight. Shares were rising $1.05, or 4%, to $27.42.

Landec

(LNDC) - Get Report

swung to a first-quarter profit, but the Menlo Park, Calif., company lost ground after it offered a disappointing forecast. Shares dropped $1.03, or 9.3%, to $10.07.

Molecular Devices

( MDCC) plummeted after the Sunnyvale, Calif.-based company, which makes bioanalytical-measurement systems, cut its third-quarter guidance. The company cited softer-than-expected demand from pharmaceutical companies for drug-discovery and life-sciences products. Shares fell $3.80, or 17.4%, to $18.04.