Testosterone can skew one's judgment, creating the impression that decisions are best taken alone even in situations that call for collaboration, according to a study released Wednesday.

In a clever set of experiments, scientists led by Nicholas Wright at the University of London showed that women given a dose of testosterone become less inclined to act in concert even when it was clearly in their interest to do so.

U.S. regulators on Tuesday approved Kalydeco, a new, gene-targeted drug treatment for people who have a rare kind of the incurable lung disease cystic fibrosis.

Made by the Massachusetts-based Vertex Pharmaceuticals, Kalydeco (ivacaftor) was approved by the US Food and Drug Administration on a fast-track for drugs that may offer big advances over standard therapy.

U.S. authorities on Monday approved a new drug to treat the most common form of skin cancer, basal cell carcinoma, which is rarely lethal but can spread if left untreated.

Erivedge (vismodegib) is made by Genentech, a U.S. subsidiary of the Swiss drug giant Roche, and was approved by the Food and Drug Administration after an expedited review for drugs that offer the potential for major advances in treatment.

Measuring blood pressure on both arms rather than only one can reveal an elevated risk of heart disease or even death, according to a study released Monday.

In a review of medical literature, researchers at the University of Exeter found that a difference in the so-called systolic blood pressure between arms can be a useful indicator of the likelihood of heart trouble.

Zapping testicles with ultrasound can reduce sperm counts and might be used in the future as an inexpensive, reliable and reversible male contraceptive, according to U.S. researchers.

Scientists from the University of North Carolina School of Medicine, who conducted experiments on male rats, issued their findings on Saturday in the journal Reproductive Biology and Endocrinology.

Bugs that cause childhood pneumonia and meningitis have evolved to evade vaccines by swapping bits of their genome with other bacteria, according to a study published Sunday.

The findings, published in Nature Genetics, show how quickly these life-threatening pathogens can disguise themselves with borrowed genetic decoys, and how hard it is for medicine to keep up.

Mohammed Qasim, a 58-year-old butcher, is traumatized, depressed and anxious -- like 50 percent of his fellow Afghans after 30 years of war, according to government figures.

Qasim saw his wife, daughter-in-law and two grandsons aged five and six die in a horrific suicide bombing in Kabul last month.

Amylin Pharmaceuticals won approval Friday for its long-delayed diabetes drug Bydureon, a next-generation treatment that requires fewer injections than the company's 7-year old diabetes medicine, Byetta.

Bydureon is a once-a-week version of Byetta, which is taken twice a day to control blood sugar. Amylin executives say the new drug's convenient regimen will give it a competitive advantage in the marketplace. After multiple delays however, it enters a crowded market, including one diabetes treatment in the same class that has shown superior results.

U.S. authorities on Friday seized nine shipments of orange juice from Brazil and Canada after their contents tested positive for an illegal fungicide.

The Food and Drug Administration said the orange juice tested positive for carbendazim, a pesticide that is not legal for use on oranges in the United States but is approved in Brazil and some other countries.

Around 100 Pakistani heart patients have died after taking faulty medicine made locally and dozens more are in a critical condition in hospital, government officials said Thursday.

"Nearly 100 patients have died due to a reaction to heart drugs," said Shahbaz Sharif, the head of the government in central Punjab province.