In brief– Research news and discovery

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ONE OF the big questions about the drug thalidomide was why the birth defects that affected thousands of babies in the 1950s did not show up in tests on mice. Now the compound that protected mice has been identified, and could lead to safer versions of the drug, which has been rehabilitated as a powerful anti-cancer agent .

Jürgen Knobloch , now at the

University of Cologne in Germany, and his colleagues wanted to know what made mouse embryos immune to the harmful side effects that plague human and chicken embryos.

They discovered that chicken and human embryos exposed to thalidomide produce superoxide, a powerful oxidising agent which causes cell death and birth defects. It turns out that mice are

protected from superoxide because they also make the antioxidant glutathione, which mops up the superoxide before it can damage cells. Human and chicken embryonic cells treated with glutathione had reduced levels of superoxide and less cell death (Molecular Pharmaceutics, DOI: 10.1021/mp8001232).

The researchers hope their findings will lead to modified versions of thalidomide that don’t produce superoxide, but retain the ability to fight cancer.

Why thalidomide spared mouse pups

HIDDEN alien moons that could harbour life can be revealed by the wobbles of their planets.

Almost all the 30 known exoplanets that sit within the habitable zone of their stars are gas giants. “But they might have rocky, possibly Earth-like moons,” says David Kipping of University College London.

His calculations , which will appear in Monthly Notices of the Royal Astronomical Society, show that such moons would reveal their presence when the planet passes in front of its star as viewed from Earth. A moon would induce a wobble in the planet’s orbit, so the planet’s position and velocity would differ slightly on each transit. Existing telescopes could detect an Earth-mass moon around a Neptune-mass gas planet, he says.

If it wobbles, look for Earth 2.0

IF YOU’RE planning a lab experiment, be wary of using plastic equipment. Plastic test tubes and pipettes leach compounds on contact with water that may alter your findings.

While testing experimental Parkinson’s drugs, biochemist Andrew Holt of the University of Alberta in Edmonton, Canada, noticed that measurements of the enzyme MAO-B were all over the place. When his team investigated, they found that water stored in plastic microcentrifuge tubes blocked MAO-B and contained traces of an antimicrobial compound added to the tubes by the manufacturer (Science, DOI: 10.1126/science.1162395). Plastic pipette tips leached chemicals that block reactions, and plastic plates made MAO-B more active.

“It’s inevitable that a lot of data that’s in the public domain will be skewed,” says Holt, though he has not yet identified erroneous data or conclusions in published work.

Avoid plastic

THE shortfin mako shark’s petrifying ability to slice through the ocean at up to 80 kilometres an hour relies on a trick of its scaly skin. The scales can reduce drag by bristling to create tiny wells across the skin’s surface – just like the dimples on a golf ball.

Grooves on the 200-micrometre-long enamel scales of the fast-swimming shark are known to reduce drag slightly even when lying flat. Because the indentations on a golf ball reduce drag as it moves through the air, Amy Lang and her team at the University of Alabama in Tuscaloosa tested

whether a similar effect could be seen with shark skin when the scales are erect.

The team made artificial shortfin mako skin with scales that bristled at 90 degrees to the surface. They then put the artificial skin in a steady stream of water moving at 20 centimetres per second. The water contained particles that showed the flow patterns around the scales.

The team found that whirlpools formed in the cavities between the scales. These vortices would buffer the shark from the water and prevent the formation of a turbulent wake, which would exert a backward pull (Bioinspiration and Biomimetics, DOI: 10.1088/1748-3182/3/4/046005).

The team say the findings could inspire the design of more effective torpedoes or underwater vehicles.

Bristling skin is the secret of the high-speed shark

16 | NewScientist | 15 November 2008 www.newscientist.com