The Los Angeles Business Journal’s index of largest local public companies closed up for the week ended Dec. 10 as the markets reacted to news of a lower trade deficit and other encouraging economic signs.

The weighted LABJ index rose 1.37 percent to 117.28, with gainers outpacing decliners 110 to 62.

Among the biggest gainers was Korn/Ferry International Inc., which jumped nearly 25 percent to $22.44 after the Los Angeles staffing giant reported better-than-expected second-quarter earnings.

American Apparel Inc. rose more than 20 percent to $1.75 after the Los Angeles apparel company said it sold $1.67 million worth of its common shares to Chief Executive Dov Charney in a private placement, proceeds of which will fund equity grants to managers as part of their compensation package.

Valencia biotech MannKind Inc., which is awaiting long-delayed U.S. regulatory approval of its first product, jumped 20 percent to $7.51 following upbeat remarks made by its chief financial officer at an investor conference.

Koreatown’s Nara Bancorp Inc. and Center Financial Corp. announced that they will merge to create the nation’s largest Korean-American bank. Both banks rose 10 percent, with Nara closing at $10.34 and Center at $7.15.

Among a handful of significant decliners was Los Angeles Internet security software developer CyberDefender Corp., which dropped more than 20 percent to $2.54 after disclosing that it would be filing amended financial reports for fiscal 2009 and the first three quarters of 2010 by the end of the month.

Monrovia prepaid debit card provider Green Dot Corp., which went public in July, fell nearly 10 percent to $53.84 after pricing a secondary offering of up to $100 million of its common shares that were being sold by existing stockholders.