Women in stilettos and ostriches have unwittingly contributed to scientific advancement by showing researchers how to design a prosthetic leg better adapted for walking, said a study published Wednesday.

The best prosthesis for above-knee amputees, and for humanoid robots, would work nothing like the human leg, scientists found, -- but like that of an ostrich or the synthetic limbs used by South African amputee sprinter Oscar Pistorius.

Forty-two percent of the U.S. population could be obese by 2030, up from about one-third currently, and the associated rise in health woes would likely cost $550 billion over two decades, said a study on Monday.

In real numbers, the increase would mean about 32 million more obese people, said the forecast led by researchers at Duke University in North Carolina and published in the American Journal of Preventive Medicine.

From liposuction in Athens to an eye operation in Dubai, the lucrative market in medical tourism is on the up, tempting ever more countries to look for ways to profit from foreign patient care.

"Everyone wants their share of the pie," Sanjiv Malik, director of DM Healthcare, a Dubai-based network of hospitals, said at a recent conference on medical tourism attended by more than 300 professionals here.

For desperate Vietnamese cancer patients ground rhinoceros horn is seen as an elixir of life -- a medically unproven and illegal obsession that threatens the very survival of the world's wild rhinos.

The substance, which shares the same protein found in human fingernails, sells for thousands of dollars an ounce in Vietnam. Soaring demand has led to a bloodbath in South Africa as poachers kill record numbers of the creatures.

People who drive long distances to work are more likely to be overweight and have poorer fitness levels than people who live closer to their jobs, a U.S. study said Tuesday.

The study in the American Journal of Preventive Medicine was based on data from nearly 4,300 people in Texas near the major metropolitan hubs of Dallas-Fort Worth -- one of the top five most congested areas in the United States -- and nearby Austin.

German pharmaceutical giant Bayer AG has challenged a ground-breaking Indian ruling that allowed a local firm to produce a vastly cheaper copy of its patented drug for kidney and liver cancer.

India's patents chief ruled in March the price Bayer charged for the drug, Nexavar, was "exorbitant" and ordered the firm to give a so-called "compulsory license" to make the medicine to Indian company Natco Pharma.

Researchers said Monday they were a step closer to developing a vaccine against the type of meningitis that mostly affects Europe and North America and kills hundreds every year.

A trial in adolescents in Australia, Poland and Spain showed them developing an immune response without serious side-effects, according to a study published in The Lancet Infectious Diseases medical journal.

Indian generic drug giant Cipla said Friday it had slashed by up to 76 percent prices of three anti-cancer medicines in what it called a "humanitarian" move and promised to cut the costs of more products.

There are 2.5 million cases of cancer diagnosed in India each year, according to the World Health Organisation, with most patients receiving inadequate treatment as drugs are priced beyond their reach.

Men rarely get breast cancer, but those who do often don't survive as long as women, largely because they don't even realize they can get it and are slow to recognize the warning signs, researchers say.

On average, women with breast cancer lived two years longer than men in the biggest study yet of the disease in males.

Tainted dog food has sickened at least 14 people in the United States, health officials said Friday.

"Humans can become ill by handling pet products contaminated with salmonella, and by coming in contact with pets or with surfaces that have been contaminated," Ohio's health department said in a statement.