Life Sciences

Researchers have long said they won't be able to understand the brain until they can put together a "wiring diagram" – a map of how billions of neurons are interconnected. Now, researchers at the Salk Institute for Biological Studies have jumped what many believe to be a major hurdle to preparing that chart: identifying all of the connections to a single neuron. In the March 1 issue of the journal Neuron, the researchers describe how they modified the deadly rabies virus, turning it into a tool that can cross the synaptic space of a targeted nerve cell just once to identify all the neurons…

Digital atlases of the brains of humans, monkeys, dogs, cats, mice, birds and other animals have been created and posted online by researchers at the UC Davis Center for Neuroscience. BrainMaps.org features the highest resolution whole-brain atlases ever constructed, with over 50 terabytes of brain image data directly accessible online. Users can explore the brains of humans and a variety of other species at an unprecedented level of detail, from a broad view of the brain to the fine details of nerves and connections. The website also includes a suite of free, downloadable tools for…

Promiscuity is common among female rodents, leading to competition between the sperm of rival males over who fertilizes the eggs. It now seems that possessing a longer penis may give males an advantage in this competition, according to new research to be published in the March issue of The American Naturalist. Dr. Steve Ramm, an evolutionary biologist at the University of Liverpool, UK, compared the relative size of the penis bone in several mammal groups: "The data for rodents seem pretty clear cut. Species where sexual competition between males is most intense also tend to have the longest…

Seafood allergy sufferers may soon be able to eat prawns without the fear of an adverse reaction. Chinese scientists have taken a promising step towards removing from prawns the proteins that cause an allergic response without resorting to genetic manipulation, reports Lisa Richards in Chemistry & Industry, the magazine of the SCI. Li Zhenxing led the research at the Ocean University of China. The team revealed that treating prawns with a combination of heat and irradiation significantly reduced the level of reactive proteins called allergens. They took blood from patients with shrimp…

Once roofed by ice for millennia, a 10,000 square km portion of the Antarctic seabed represents a true frontier, one of Earth's most pristine marine ecosystems, made suddenly accessible to exploration by the collapse of the Larsen A and B ice shelves, 12 and five years ago respectively. Now it has yielded secrets to some 52 marine explorers who accomplished the seabed's first comprehensive biological survey during a 10-week expedition aboard the German research vessel Polarstern. While their families at home in 14 countries were enjoying New Year's dinners, experts on the powerful…

Scientists from Université Laval’s Faculty of Medicine have succeeded in producing neurons in vitro using stem cells extracted from adult human skin. This is the first time such an advanced state of nerve cell differentiation has been achieved from human skin, according to lead researcher Professor François Berthod. This breakthrough could eventually lead to revolutionary advances in the treatment of neurodegenerative illnesses such as Parkinson’s disease. Berthod and his team described the method used to produce these neurons in a recent issue of the Journal of Cellular Physiology. The…

THIS IS A CONTEST: THE WINNER WILL BE SENT A FREE COPY OF MY BOOK "Challenging Nature."   The five chemicals shown in the picture below are all consumed by millions of Americans as a means for increasing alertness (sometimes some are used for other purposes as well).   But each has different effects on the human body in terms of addictiveness, carcinogenicity, acute toxicity, and actual effectiveness, as illustrated.  Based on this information, can you decide which is legal and which is not?   CLICK IMAGE TO SEE LARGER VERSION   Consumption of each chemical has a…

The life cycles of many viruses include a self-assembly stage in which a powerful molecular motor must pack the DNA genome into the virus's preformed shell (the capsid). How it manages this intricate feat has been subject to debate, but we know that the DNA passes into the capsid shell through a channel formed by a structure called the connector. Scientists have speculated that rotation of the connector complex might feed the DNA into the capsid as it turns. In a new study published online this week in the open access journal PLoS Biology, researchers Thorsten Hugel, Jens Michaelis, Craig…

How does the heart attain its characteristic shape? Shape may be sculpted by cell movement, cell division, or changes in cell size and shape, all of which can be influenced by the local environment. The heart appears as a simple tube early in development; later, the tube walls bulge outward to form the cardiac chambers. In a new study published online in the open access journal PLoS Biology, Heidi Auman, Deborah Yelon, and colleagues found, by using transgenic zebrafish in which they can watch individual cardiac cells, that cells change size and shape, enlarging and elongating to form the…

Newborns with respiratory distress should be evaluated for primary ciliary dyskinesia, a rare genetic disease that has features similar to cystic fibrosis, says Thomas Ferkol, M.D., from Washington University School of Medicine in St. Louis. He reports finding that about 80 percent of patients with primary ciliary dyskinesia (PCD) have a history of newborn respiratory distress. "The diagnosis of PCD requires a high index of suspicion, but PCD must be considered in any term newborn who develops respiratory distress or persistent hypoxemia (low oxygen in the blood), especially those who have…