U.S. regulators on Thursday took steps to ban trans fat from processed foods like microwave popcorn and frozen pizzas, saying the artery-clogging oils are not safe for humans to eat.

"Partially hydrogenated oils (PHOs), the primary dietary source of artificial trans fat in processed foods, are not 'generally recognized as safe' for use in food," the Food and Drug Administration said in a statement.

Scientists said Wednesday they had found an "invisibility cloak" that allows the AIDS virus to lurk unnoticed in human cells after infection and replicate without triggering the immune system.

And they managed to "uncloak" the virus with an experimental drug in lab-grown cells -- a feat that may lead to new and better HIV treatments, the team wrote in the journal Nature.

Scientists said Wednesday they may have found the earliest signs yet of autism in infants -- babies as young as two months starting to evade other people's eyes.

Eye-evasion has long been regarded as a hallmark of autism, but its potential value as an early diagnostic tool had not been explored before, a team of researchers wrote in the journal Nature.

Spain said Wednesday that a woman who just returned from Saudi Arabia has been infected by the MERS coronavirus in the country's first case of the deadly disease.

The patient, who was born in Morocco but lives in Spain, is receiving treatment at a Madrid hospital and is in a "stable" condition, the health ministry said in a statement.

Cynthia Carrion-Norton flits high-heeled around the Philippine capital with energy levels belying her years, thankful for a controversial treatment she highly recommends to fellow sixty-somethings.

Carrion-Norton, 66, a member of the Philippine Olympic Committee and a former undersecretary for medical tourism, credits her vitality to adult stem cell therapy.

A heated debate on proposals to legalize euthanasia for minors in Belgium, one of the few countries to allow it for adults, intensified on Wednesday with supporters and opponents pressing their case.

Proposed legislation would allow the euthanasia of minors so long as they are judged capable of deciding for themselves -- a move favored by three quarters of Belgians, according to a recent opinion poll.

Older men treated with testosterone run a higher risk of death, heart attacks and strokes, according to a study out Tuesday suggesting the hormone therapy may need to be reconsidered.

The researchers followed more than 8,700 men who had low levels of the hormone, of whom 1,223 took a testosterone supplement for a median period of around two years.

Nguyen Thi Yen rolls up the sleeves of her white lab coat and delicately slips her arms into a box covered by a sheath of mesh netting. Immediately, the feeding frenzy begins.

Hundreds of mosquitoes light on her thin forearms and swarm her manicured fingers. They spit, bite and suck until becoming drunk with blood, their bulging bellies glowing red. Yen laughs in delight while her so-called "pets" enjoy their lunch and prepare to mate.

Doctors sounded a warning Tuesday over a rise in ADHD diagnoses, saying some children may be needlessly taking powerful drugs intended to correct a poorly understood disorder.

Writing in the British Medical Journal (BMJ), the researchers noted treatment for attention-deficit/hyperactivity disorder (ADHD) had risen massively in recent years, even though its causes are unclear and drugs can have adverse effects.

Evelina Gonzalez was supposed to undergo cancer surgery in July following chemotherapy but wound up shuttling from hospital to hospital in search of an available operating table. On the crest of her left breast, a mocha-colored tumor doubled in size and now bulges through her white spandex tank top.

Gonzalez is on a list of 31 breast cancer patients waiting to have tumors removed at one of Venezuela's biggest medical facilities, Maracay's Central Hospital. But like legions of the sick across the country, she's been neglected by a health care system doctors say is collapsing after years of deterioration.