Scientists Closer to Unfolding Mysteries of Prion Formation in Mad Cow Disease
Scientific American
09 May 2007
N Swaminathan
Photo courtesy of Istockphoto/Lisa Young
Area: United States
Short elements within a prion protein's sequence can cause it to activate and even cross the species barrier to spread neurodegenerative disorders such as Creutzfeldt-Jakob disease to humans
Prions, the maddening, infectious proteins, and the diseases they trigger, such as the fatal neurodegenerative disorder in humans, Creutzfeldt-Jakob disease—as well as its bovine counterpart, mad cow disease—have baffled scientists for decades. Although researchers know what they are (abnormally folded proteins) and the illnesses that they cause, how they form and multiply has remained elusive. Today, a study appearing in an advance online publication of the journal Nature announces a first step in demystifying the mechanisms governing prion behavior.
Studying yeast proteins, a pair of researchers at the Massachusetts Institute of Technology's Whitehead Institute of Biomedical Research discovered that a highly specific section of a prion protein's amino-acid sequence controls its switch to the prion state. In addition, this same segment regulates its ability to cross species barriers. Biology professor Susan Lindquist and postdoctoral researcher Peter Tessier examined the behavior of prions in baker's yeast (Saccharomyces cerevisiae). (Unlike in humans or cows, these yeast prions do not negatively affect their hosts.)
Lyme and Tick-borne Diseases Research Center Opens at Columbia
EmpireStateNews.net
08 May 2007
Area: New York USA
Columbia University Medical Center has opened the first endowed research center for chronic Lyme disease in the world. The Lyme & Tick-Borne Diseases Research Center in New York will use its vast resources to bring together various disciplines from within and outside the University to address fundamental clinical and basic science questions that plague adults and children affected by Lyme disease. The center’s clinical and research mission includes studies of new diagnostic tests, clinical phenomenology, immunopathogenesis, co-infections, genetic markers of vulnerability, brain imaging, neuoropathology of post-mortem brains, well-controlled studies of new treatments and tick pathogens.
This Center will serve as a national resource, providing pilot grants to researchers nation-wide and focusing the latest scientific technology on helping to resolve the problems of chronic Lyme disease. As Lyme cases increase worldwide, so does the development of chronic disease which may result from a delayed diagnosis and delayed or inadequate treatment. While much is known about early Lyme disease, relatively little is known about chronic Lyme disease, despite its disabling effects, which may include arthritis, cognitive loss, peripheral neuropathies, and debilitating fatigue.
Deadly Ocean Toxin at Worst-Ever LevelDaily Pilot
09 May 2007
M Alexander
Photo courtesy of Mark Dustin/Daily Pilot
Area: California USA
Scientists find record-high concentration of domoic acid in Southland. Deaths particularly bad for Orange County marine life. The natural toxin that killed hundreds of Southern California birds, sea lions, dolphins and other coastal marine life in the last two weeks had been at its highest levels ever recorded in local waters, scientists said Wednesday. And while concentrations of the neurotoxin domoic acid are lower now, the die-off hasn't fully halted yet. Wildlife care and rescue staff from throughout Southern California gathered at a bird rescue center in San Pedro for a news conference where USC professor David Caron announced the results. The week of April 26 showed twice as much domoic acid as ever before, Caron said.
"This is the worst," he said. "It's the highest numbers we've ever seen in terms of concentration." That much poison is bad news for animals. The toxin moves up the food chain from tiny plankton to sardines and shellfish, which larger animals then eat in enough numbers to get a heavy dose. Domoic acid can cause massive seizures and brain damage, Caron said.
Plague Concerns Climb as More Animals DieDenver Post
09 May 2007
JP Meyer
Photo courtesy of Denver Post/John Prieto
Area: Denver, CO USA
Reports of dead squirrels continue to come into a hotline set up by the state health department to track what could be the first plague outbreak in Denver since 1968. There have been positive plague tests on 15 squirrels and one rabbit in Denver, Jefferson and Arapahoe counties. Thirteen of the animals were in Denver's City Park area, health officials said. Between Friday and Monday, nearly 200 calls came into the hotline, reporting dead animals mostly in the City Park neighborhood, said John Pape, the state epidemiologist.
The city of Boulder this week closed Tom Watson Park to test a prairie dog town that has been unusually inactive. "We're still trying to determine how widespread it is," Pape said. "I wouldn't apply the term 'outbreak' to this," he said. "We normally see this kind of rodent die-off where plague is occurring, and it just happens to be occurring in Denver this year."
Stopping U.S. Turtles from Going to ChinaTime
08 May 2007
H Hylton
Photo courtesy of Bobby Yip/Reuters/Corbis
Globalization has brought Americans tech support from India, Chinese-made Christmas lights, T-shirts from Bangladesh and those inexpensive Aussie wines, but U.S. conservationists are sounding the alarm that global trade is a two way street that threatens American wildlife — thanks to rising economic tides in Asia and the fast and easy import-export routes between China and the U.S. Turtles — except for the occasional slow road-crosser — are not on most Americans' radar. But the Asian appetite for turtles, whose meat and body parts are believed to hold a variety of medicinal and life-enhancing qualities, is creating a global market for U.S. turtles and tortoises.
During the Great Depression, Americans living near the country's wetlands harvested high protein turtle meat, sometimes so aggressively that it threatened local species. In the early 1930s thousands of pounds of terrapin were harvested in Maryland, but by 1937 the yield had fallen to just 537 pounds, according to Peter Paul van Dijk, director of the tortoise and freshwater turtle biodiversity program at Virginia-based Conservation International (CI). Turtle meat is still eaten in parts of rural America and there is a growing domestic market in urban Asian-American communities.
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