Around one in 20 men is infertile, but despite the best efforts of scientists, in many cases the underlying causes of infertility have remained a mystery.

Substances produced by living organisms found in nature—so-called "natural products"—have played a critical role in the development of drugs for life-threatening conditions. The anticancer agent Taxol was sourced from a plant, penicillin from a fungus, and a number of recent breakthroughs have resulted in the development and approval of anticancer drugs derived from marine sources such as coral and sponges.

Two proteins that are abnormally modified in the brains of patients with Alzheimer disease collude, resulting in ill effects on the crucial energy centers of brain cells, according to new findings published online in Neurobiology of Aging.