Stocks mixed on volatile oil prices

NEW YORK — Wall Street started the week mixed Monday as investors weighed volatility in oil prices and new hope for the financial sector after Lehman Brothers posted results.

Crude oil futures swung wildly soaring to a trading record of $139.89 before settling at $134.61 a barrel.

Lehman, meanwhile, posted a nearly $3 billion loss. Chief Executive Richard Fuld took the blame, saying the bank was too slow in reacting to the credit market's tumult.

The Dow Jones industrial average fell 38.27, or 0.31 percent, to 12,269.08. The S&P 500 index added 0.11, or 0.01 percent, to 1,360.14. The Nasdaq composite rose 20.28, or 0.83 percent, to 2,474.78.

Fed chairman frets over medical costs

WASHINGTON — Bolstering the performance of the U.S. health care system is one of the top challenges facing the country, Federal Reserve Chairman Ben Bernanke said Monday.

New technologies and treatments are allowing people to live healthier, longer and more productive lives. But the aging of millions of baby boomers coupled with rising costs are accounting for a growing share of personal and government budgets, the Fed chief said.

Ex-Broadcom chief pleads not guilty

SANTA ANA, Calif. — Broadcom co-founder Henry T. Nicholas III pleaded not guilty Monday to federal drug and securities fraud charges.

The plea involves 21 counts against the 48-year-old technology billionaire. One indictment details what authorities say was one of the largest stock-option backdating cases in U.S. history. The other accuses Nicholas of drugging business cohorts, hiring prostitutes and maintaining a drug warehouse.

AIG ousts its CEO, names a successor

NEW YORK — AIG's Martin Sullivan lost his job as the head of the world's largest insurer, becoming the latest CEO to be sent packing after racking up huge losses on bad mortgage-market bets.

American International Group named former Citigroup executive Robert Willumstad to replace Sullivan, effective immediately.

Willumstad, who has been on AIG's board since 2006, said Monday he will conduct a review of AIG over the next two to three months. Willumstad's review could mean more management reshuffling at AIG, and could result in the company shedding some of its businesses. Though Willumstad said "it would be very hard for me to imagine seeing the insurance businesses broken up," he also said that "nothing is off the table, and there will be no sacred cows."

Hybrid auto leader short on batteries

TOKYO — Toyota is struggling to keep up with booming demand for its hybrid vehicles because it can't make enough of the batteries that are key parts in the hit "green" cars, a senior executive said Monday.

The crunch is likely to remain the rest of the year, as battery production can't be boosted until next year, said Takeshi Uchiyamada. Toyota leads all automakers in hybrids sold at about 1.5 million vehicles.