The Los Angeles Business Journal’s index of largest local public companies closed up for the week.

The weighted LABJ Stock Index rose 0.9 percent to 170.84 for the trading week ended Sept. 20. Gainers outpaced decliners 107 to 50, with nine companies unchanged.

The biggest mover was Virtual Piggy Inc., plunging 25 percent to $1.51. The Hermosa Beach provider of online financial products for kids was hurt by negative articles about the company’s founders and financial backers.

Kythera Biopharmaceuticals Inc. for the second week was among the biggest gainers, adding another 18 percent to close at $41.37. The Calabasas aesthetic medicine developer continued to benefit from positive clinical study results.

NetSol Technologies Inc. fell 11 percent to $9.96. Investors took profits after gains resulting from the Calabasas software company reporting stronger fiscal fourth quarter revenue and profit.

Cherokee Inc. rose 9.6 percent to $13.01. The Sherman Oaks licenser of apparel and accessory lines recently reported a strong second quarter.