N Nitrogen

In 1492, Columbus sailed the ocean blue, but when he returned from 'cross the seas, did he bring with him a new disease?

The 1936 film Reefer Madness developed a cult following because of its over-the-top depiction of the evils of marijuana. Getting stoned and going to a midnight showing became a ritual for many college students.

DURBAN, South Africa--Former entomologist Diarmid Campbell-Lendrum of the World Health Organization worries about nosebleeds more than the average person. That's because he's one of the estimated 12 million people worldwide afflicted with leishmaniasis --a potentially fatal parasitic disease characterized most often by lesions on the skin and/or mucus membranes--caused by the bite of a sandfly.

Large numbers of infants and toddlers have died from lead poisoning in Nigerian villages where their parents process gold ore inside their family compounds, according to a report published Tuesday by an international team of researchers.

Peering through a microscope at a plate of cells one day, Ralph M. Steinman spied something no one had ever seen before. It was the early 1970s, and he was a researcher at the Rockefeller University on Manhattan’s Upper East Side. At the time, scientists were still piecing together the basic building blocks of the immune system. They had figured out that there are B cells, white blood cells that help to identify foreign invaders, and T cells, another type of white blood cell that attacks those invaders. What puzzled them, however, was what triggered those T cells and B cells to go to work in the first place. Steinman glimpsed what he thought might be the missing piece: strange, spindly-armed cells unlike any he had ever noticed.

It’s a rare kind of research that incites a frenzied panic before it’s even published. But it’s flu season, and influenza science has a way of causing a stir this time of year.

A new variant of an influenza virus that circulates in pigs has been jumping occasionally into people, providing a surprisingly early opportunity for public health officials to test out some of the lessons learned from the 2009 H1N1 pandemic .