A Google project to develop nanoparticles that can detect cancer cells inside the body is a useful contribution but faces important hurdles, experts said on Wednesday.

The technology could yield "another tool in our arsenal (but) in my opinion, it won't be a game-changer in terms of diagnostics," said Agnes Buzyn, president of France's National Cancer Institute (InCA).

One of the widest investigations into autism has implicated several dozen genes, boosting the search for a diagnostic tool and new treatments, scientists said on Wednesday.

Mutations in these genes emerged in two studies which compared thousands of people with autism spectrum disorder against family members with or without ASD.

Scientists using stem cells said on Wednesday they had built the world's first "mini-stomachs" -- tiny clusters of human gastric tissue that could spur research into cancer, ulcers and diabetes.

Called gastric organoids, the lab-dish tissue comprises buds of cells that are "a miniature version of the stomach", the researchers said.

The rate of new Ebola infections appears to be slowing in hard-hit Liberia, but the crisis is far from over, according to the World Health Organization.

"It appears that the trend is real in Liberia and there may indeed be a slowing of the epidemic there," WHO assistant director-general Bruce Aylward told reporters in Geneva.

A report warned Wednesday of a looming tuberculosis-diabetes epidemic as the two diseases intertwine in many countries, driven in part by a rise in unhealthy lifestyles.

Having diabetes triples a person's risk of contracting TB, which killed about 1.5 million people last year, said the report compiled by the International Union Against Tuberculosis and Lung Disease and the World Diabetes Foundation.

The deadly Middle East Respiratory Syndrome coronavirus (MERS-CoV) remains a significant threat to Saudi Arabia, the health ministry said on Tuesday after a series of cases in the western city of Taif.

The virus, believed to be transmitted from camels to humans, has infected at least 17 people in Taif since September 5, a ministry statement said.

Drink lots of milk to strengthen your bones and boost your health, doctors say.

But a study in The BMJ medical journal Wednesday said Swedes with a high intake of cow's milk died younger -- and women suffered more fractures.

U.S. President Barack Obama and the Red Cross have offered hope that the battle against the deadly West African Ebola outbreak is being won, amid a dramatic drop in bodies collected in Liberia's capital.

Obama on Tuesday hailed progress in the fight against the disease, which has already killed almost 5,000 people, but said Washington would remain "vigilant," and stressed that science, not fear, should guide the response to the virus.

The Red Cross said Tuesday the weekly total of Ebola victims collected by its body disposal teams around the Liberian capital is falling dramatically, indicating a sharp drop in the spread of the epidemic.

The announcement appears at odds with an assessment by the World Health Organization (WHO), which said last week transmission "remains intense" in the capitals of Liberia and neighbouring Guinea and Sierra Leone.

Is a violent criminal born that way, or shaped by childhood experiences and circumstances?

Delving into one of oldest questions in psychology, some scientists have suggested genes may contribute to roughly half of the influence -- by affecting complex brain chemistry, for instance.