February 14, 2013 |
About 30,000 years ago, a tiny mutation arose in a gene known as EDAR and began to spread rapidly in central China, eventually becoming common in the region. This week, scientists at Harvard University offered some explanations for why the EDAR mutation may have been so successful - by observing how it affects mice, animals long used in disease research but never before pressed into service for the study of human evolution. The small change, substituting one chemical letter of DNA for another, may have helped humans in Asia survive crippling heat and humidity by endowing them with extra sweat glands, the scientists reported Thursday in the journal Cell.
February 13, 2013 |
Researchers at USC have made mice insensitive to near-freezing temperatures by deactivating select neurons, a development that could one day lead to new treatments for pain in humans. In a study published Tuesday in the Journal of Neuroscience, researchers used a bacterial toxin to kill neurons equipped with so-called TRPM8 channels, cellular structures that help relay sensations of cold. (The pathway is also responsible for sensing menthol, the cooling component of mint.) Neurons that sense heat and mechanical pain were left intact, however.
January 18, 2013 |
Why are women more prone to autoimmune diseases like lupus, multiple sclerosis and rheumatoid arthritis? A new study in mice points to a possible contributor: different types of bacteria that populate our guts. It goes like this: Different mixes of bacteria reside in the innards of male and female mice. Those bacteria, in turn, affect the chemistry of the animals' bodies -- and, it appears, their risk of autoimmunity. The study, just published in Science , was done by Janet Markle of the Hospital for Sick Children Research Institute, Toronto, and colleagues. It's a little complicated, with players that include sex hormones, fatty chemicals, immune cells and a whole host of microscopic life forms.
January 15, 2013 |
Despite all the attempts to legislate America's way out of obesity with food regulations, a new study out of UC Irvine suggests that there could be more to fat than sloth and supersized sodas. Pregnant mice exposed to a chemical commonly used in PVC -- best known as the material used for piping but also a component in home furnishings, children's toys, packaging and lots of other everyday items -- gave birth to offspring with a tendency to obesity. And their offspring's offspring, which were never exposed to the chemical.
January 10, 2013 |
Anyone who's gone to too many rock concerts or worked with loud machinery for too long (or listened to too many kazillion-decibel advertisements at a movie theater) may eventually pay the price: hearing loss caused by damage to tiny, sound-transmitting cells in the inner ear. Researchers now report they can regenerate some of these crucial “hair cells” in the inner ears of mice and restore noise-induced damage to some extent. It's something that hearing scientists have been hoping for ages (though we will avoid using the term “holy grail”)
January 9, 2013 |
The Consumer Electronics Show has a dizzying array of tech accessories, but every once in a while, a few of those find a way to stand out. Here are some of the ones that caught my eye. Lucien Element's $650 iPhone 5 case In a world of iPhones, there are cases and then there are cases . Lucien Elements makes the latter, specializing in luxury cases for iPhone users who want to protect their phones with style. Their top product at CES? A $650 crocodile-skin case with studs for the edges of the iPhone.
November 3, 2012 |
A tiny, porthole-shaped device that allows scientists to peer into the guts of a living mouse may provide researchers with valuable new insights into the lethal migration of rogue cancer cells. In a procedure evocative of cows who have been fitted with cannula, or "windows," so that veterinarians can observe their digestion, scientists in the Netherlands surgically implanted glass windows in the abdomens of mice so that they could observe their livers and other organs. Researchers then used powerful microscopes to track the movements of individual cancer cells for up to a month.
November 1, 2012 |
Inflammatory bowel disease -- a range of conditions including Crohn's disease and ulcerative colitis -- afflicts an estimated 1.4 million Americans. Now some scientists in France have come up with a novel potential therapy: an enzyme that calms down the gut delivered via a genetically engineered bacterium. The approach -- tested so far only on mice and pieces of inflamed human gut tissue in the lab -- was reported in a paper in this week's Science Translational Medicine . Crohn's and ulcerative colitis, which range in severity and can be chronic or recurring, develop when parts of the body's immune system turn traitor and -- for poorly understood reasons -- start attacking the gut. Symptoms include diarrhea, cramping, weight loss, ulcers and intestinal scarring.
October 31, 2012 |
Doctors have long urged people with red hair, fair skin and freckles to avoid the sun and its damaging ultraviolet rays. To venture outdoors without a wide-brimmed hat and sunscreen was simply courting skin cancer, they cautioned. Now, however, a study in mice suggests that those among us with ginger hair and fair complexions face an elevated risk of the disease even when covered up. The study, published online Wednesday in the journal Nature, suggests that the same reddish-yellow pigment that gives rise to rusty locks and an inability to tan is itself a potential trigger in the development of melanoma, the deadliest form of skin cancer.
October 11, 2012 |
Mice appear to learn to sing from other mice in a manner similar to how humans and songbirds learn, according to a new study. Songbirds are a common model animal for studying language acquisition and learning. That's because they learn to sing from those around them, and because they have specific brain networks honed for this purpose. Researchers have long held that a small group of animals including humans, songbirds, dolphins, whales and elephants are "vocal learners," while most animals are not. Instead, other animals have vocalizations that are innate and do not change during the animal's lifetime.