Scientists at the U.S. Energy Dept.'s Lawrence Berkeley National Laboratory are developing a type of artificial bone that's inspired by oysters, abalone, and other hard-shelled ocean dwellers. And they're using a property of seawater to speed the process.
When seawater freezes, it forms stacked layers of crystals. The researchers found they could exploit the same freezing process to mold ceramic materials into layered structures that mimic the properties of a substance in the shells called nacre, which makes them light and strong. The new material is four times stronger than synthetic bone used today, and less likely to trigger inflammation of surrounding tissue.
The researchers hope to come up with a light, durable scaffolding that will incorporate both natural bone cells and an organic material that will release growth-stimulating compounds as it degrades. New bone cells will then gradually fill the pores of the scaffold, fusing the natural and artificial bone together. The material might also be used in body armor and airplane and computer parts.
Connoisseurs pride themselves on their ability to judge the quality of wine by sniffing it and swishing it around in their mouths. The distinctive bouquet comes from compounds called volatiles. Scientists at the University of British Columbia in Vancouver are studying the molecules in an effort to make fine wine even finer.
Plant volatiles emit invisible chemical clouds that people perceive as smells and tastes. Today, winemakers base their harvest and fermentation practices on relatively unscientific predictions of when volatiles will be produced in the skin, flesh, and seeds of wine grapes. The Canadian researchers hope to refine that practice by using what they learn about volatiles to manipulate the grapes' genes, and maybe to overhaul pruning and fertilization methods. A paper they wrote on grape chemistry is featured in Science.
The immune system doesn't always protect us. It runs amok in diseases such as lupus, and it may also help tumors resist some anticancer drugs.
In the Feb. 10 issue of Cell, researchers at the University of California at San Diego School of Medicine report that macrophages, which normally keep connective tissue healthy, can interact with prostate cancer cells to cause inflammation. That may help explain why one important class of drugs loses effectiveness over time.
The drugs work by blocking genes that are activated by male hormones called androgens, which play a role in both normal and abnormal prostate growth. The UCSD team believes that when macrophages interact with tumor cells, they prompt changes that allow tumors to resume expressing these growth-related genes, even in the presence of the drugs. Further studies may show whether it is the inflammation that changes the activity of the drugs.
-- Malaria-carrying mosquitoes thrive in hot, humid weather, and the risk of an epidemic increases after a particularly rainy season. A team led by the University of Liverpool has developed a computer model that uses long-term weather forecasts to predict epidemics up to five months in advance. That's earlier than any other forecasting method, and may provide enough warning to kick off prevention programs. The tool, which is being tested in Botswana, combines seven different global climate models, and incorporates health statistics and data on disease vulnerability from Botswana's health ministry.
-- Scientists at the University of New South Wales in Australia hope to ease one of the world's most hated chores: cleaning the bathroom. They're developing coatings made from particles of titanium dioxide, which absorb ultraviolet light. The light prompts the particles to kill microbes -- potentially even more powerfully than bleach does. If it works, bathroom surfaces would essentially clean themselves when exposed to UV. One potential hitch is that right now the coatings can only be activated with sunlight, so the team is rejiggering the particles to work indoors.