Life Sciences and Chemistry

Answer revealed in glowing live cells

Using a new mouse model that literally glows with health- protecting molecules, researchers have rewritten part of the textbook tale about how the immune system knows when to fight germs.

Time-lapse video from a pair of Harvard Medical School labs shows how pieces of captured germs may work their way to the surface of live dendritic cells. Dendritic cells are immune cells that alert other immune cells about invading germs. Inside a dendri

Mechanism may provide insights into development and cancer

When cells divide in two, they must carefully manage the process by which their DNA is replicated and then apportioned to the daughter cells. In one critical step along the way, the replicated DNA strands – or sisters – are held together for a period by a temporary scaffold of bridging proteins. When the timing is right, the proteins unzip, allowing the DNA sisters to separate. Errors in this or other steps in cell division ca

Protein phosphatase 1 (PP1) belongs to a group of molecules that on the basis of earlier studies has been proposed to be a controlling factor for learning and memory. The ETH researchers produced genetically modified mice in which the activity of PP1 can be reduced at will. These animals were subjected to various learning and memory tests in one of which, the mice had to learn about various objects in a box. For this, they were trained on different schedules: without any interruption during learning

USDA Forest Service plant pathologists have discovered a new cause of damage to loblolly pine seedlings grown in the South – needle nematodes. In the July 2002 issue of Plant Disease, pathologists Stephen Fraedrich (SRS Insects and Diseases of Southern Forests unit in Athens, GA) and Michelle Cram (Forest Health Protection Program, Region 8) report on finding a previously undescribed species of nematode stunting the growth of pine seedlings in a Georgia nursery.

In 1998, a three-year study w

Some bottles of wine are worth thousands of dollars. But if oxygen has leaked past the cork, it could be thousand-dollar vinegar — and there’s no way to tell without opening the bottle. Now chemists at the University of California, Davis, can check an unopened bottle for spoilage using nuclear magnetic resonance (NMR), the same technology used for medical MRI scans.

Natural bacteria in wine use oxygen from the air to turn alcohol into vinegar, or acetic acid. If a wine bottle is secur

Like tiny Russian dolls, the mealybugs that infest your houseplants carry bacteria inside their cells that are themselves infected with another type of bacteria. A new study by researchers at the University of California, Davis, shows that instead of spreading from bug to bug, the second set of bacteria infected the first several times in the past and are now being passed along and evolving with them.

The knowledge could be useful for working out how the insect species are related to each o