Skimmed milk -- Straight from the cowHerds of cows producing skimmed milk could soon be roaming our pastures, reports Cath

O’Driscoll in Chemistry & Industry, the magazine of the SCI. Scientists in New Zealand have dis-covered that some cows have genes that give them a natural ability to produce skimmed milk and plan to use this information to breed herds of milkers producing only skimmed milk.

The researchers also plan to breed commercial herds producing milk with the unique charac-teristics required to make a butter that is spreadable straight from the fridge. They have already identified a cow, Marge, with the genes required to do this and say a commercial herd is likely by 2011. The milk is very low in saturated fats and so should be high in polyunsaturates and mo-nounsaturated fats.

Experts say that the discovery of these rogue milkers could completely revolutionise the dairy industry. Ed Komorowski, technical director at Dairy UK says that the New Zealand approach could be used to breed cows that still produce full-fat milk but with only the good fats, which could swing things back in favour of full-fat milk. In the UK, for example, only 25% of milk sold is full fat. ‘In future if whole milk can be made to contain unsaturated fats – which are good for you – then it might mean that people change back to whole milk products. The big thing about dairy products is taste, so this would be a way of giving the benefits of taste without the disadvantage of saturated fats,’ according to Komorowski.

This may also overcome the problem of waste. ‘If you can genetically produce milk without fat then that may turn out to be a very good solution to what might later be a big disposal issue,’ says Komorowski. Producing skimmed and semi-skimmed milk means there is a lot of fat left over.

Komorowski noted, however, that although the lower-fat milk may be healthier, it will be inter-esting to see how much milk the cows actually produce.

The rogue cows were discovered when biotech company ViaLactia screened the range of milk compositions across the entire herd of 4m New Zealand cattle. New Zealand dairy firm Fonterra has already made milk products from Marge’s milk and they maintain the positive taste.Intake of vitamin D and calcium associated with lower risk of breast cancer be-

fore menopauseWomen who consume higher amounts of calcium and vitamin D may have a lower risk of de-

veloping premenopausal breast cancer, according to a report in the May 28 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Data from animal studies have linked calcium and vitamin D to breast cancer prevention, ac-cording to background information in the article. However, epidemiologic studies on humans have been less conclusive.

Jennifer Lin, Ph.D., of Brigham and Women's Hospital and Harvard Medical School, Boston, and colleagues assessed 10,578 premenopausal and 20,909 postmenopausal women age 45 and older who were part of the Women's Health Study. At the beginning of the study (in 1993 or 1995), the women completed a questionnaire about their medical history and lifestyle, plus a food frequency questionnaire that detailed how often they consumed certain foods, beverages and supplements during the previous year. Every six months during the first year and then every year after that, participants returned follow-up questionnaires indicating whether they had been diagnosed with breast cancer.

Over an average of 10 years of follow-up, 276 premenopausal women and 743 post-menopausal women developed breast cancer. Calcium and vitamin D intake were moderately as-sociated with a lower risk of breast cancer before but not after menopause. The inverse associ-ated in premenopausal women appeared more pronounced for more aggressive breast tumors.

"A possible explanation for the evident difference by menopause status may be related to the joint relationship among calcium, vitamin D and insulinlike growth factors (IGFs)," they continue. "In vitro studies have suggested that calcium and vitamin D exert anticarcinogenic effects on breast cancer cells expressing high levels of IGF-1 and IGF binding protein 3. Calcium, vitamin D and IGF binding protein 3 have been shown in vitro to interact with each other in promoting growth inhibition in breast cancer cells." Since blood levels of these compounds decline with age, they would be more prevalent in younger, premenopausal women.

"Further investigation is warranted to study the potential utility of calcium and vitamin D in-take in reducing the risk of breast cancer," the authors conclude.

Researchers find deadly prescription drug effects 6 years before FDANorthwestern team also provides remedies for treatment, cause and prevention

CHICAGO -- Northwestern University's Charles Bennett, M.D., is a super sleuth of potentially deadly prescription drug reactions. He leads a national SWAT team of doctors called RADAR (Research on Adverse Drug Events and Reports) based out of Northwestern's Feinberg School of Medicine.

They swoop in to investigate early signs of trouble years before the Food and Drug Administra-tion (FDA) takes notice.

A new study by Bennett, the A.C. Buehler Professor in Economics and Aging at Northwestern's Feinberg School of Medicine, and a hematologist and oncologist at Northwestern Memorial Hospi-tal, found RADAR identified serious drug reactions six years earlier than the FDA and drug com-panies.

RADAR's proactive safety efforts and reports also were much more comprehensive than those from the FDA or drug companies, according to the study. RADAR's reports provided doctors with important medical insights as well as guidance for prevention, diagnosis and treatment.

The study will be published May 28 in Archives of Internal Medicine.Since Bennett launched RADAR in 1998, his research has resulted in black box warnings on

billion dollar drugs like Plavix that may have saved thousands of lives. He has also provided guidance to help physicians more safely administer drugs. More than 100,000 people die each year from reactions to medications. The FDA is under attack for its passive and inefficient meth-ods of learning about these problems.

Why is RADAR so nimble" Bennett's network includes hematologists and oncologists around the country and the world. His phone rings weekly with calls from concerned doctors alerting him to possible new trouble. After such a call, Bennett probes for clues that led to a life-threatening reaction to a drug. ‘What's the age and weight of the patient, x-rays, details of the physical exam and blood tests"' he'll ask. He'll canvas doctors to see if they've seen similar cases. If a vi-tal piece of evidence is missing, Bennett even will track down a doctor at home on a Sunday and ask her to drive back to her office to check a chart. Then Bennett and his team fit all the puzzle pieces together to figure out what happened and how to prevent it in the future.

The new study also shows, however, that the FDA and drug companies were faster than RADAR to spread the word about serious adverse drug reactions. RADAR relies on publishing its studies in peer-reviewed medical journals, a process that takes longer than the FDA's warning letters to doctors and the drug companies' package inserts.

Thus, it's time for a formal collaboration between RADAR and the FDA to wed their strengths, said Bennett, who also is co-director for cancer control of the Robert H. Lurie Comprehensive Cancer Center of Northwestern University.

"We need to work together as partners," Bennett said of the FDA. "Pharmaceutical side effects are one of the top five causes of death in this country. We want to move it out of the top five. This is the way to start that process and save thousands of lives."

Bennett envisions a formal partnership with the FDA in which he would share RADAR's investi-gations on safety issues, arrive at a joint insight on drug problems and have the FDA distribute the information to doctors.

"The old way of doing business was a large number of incomplete reports that took an aver-age of seven years to find adverse reactions to drugs," Bennett said. "We propose with our sys-tem we can cut that to between one to two years. That's a six-year savings. For a billion dollar drug, can you imagine how many people that's affecting"

In the study, Bennett compared RADAR's reports on serious events associated with 14 drugs and drug-coated cardiac stents to FDA and drug company reports. The FDA had more reports than RADAR, but RADAR's reports were more complete. Pharmaceutical companies sent out safety notifications two years earlier than RADAR reported its results in journals. However, drug companies' doctor notifications were less likely than RADAR's to include information on the inci-dence of the drug reaction, outcomes and treatment or prevention.

"Our hypothesis is that the quality, not the quantity counts," Bennett said. "A small number of very good case reports is better than a large number of very bad case reports."

Bennett leaped into pharmacovigilance -- as the field is called -- when a bad drug reaction got personal. Nearly ten years ago, he was sitting in a case conference when he heard about a woman whose kidneys, brain and blood vessels had mysteriously shut down. No one could figure out why. Bennett visited the woman, who was being kept alive on a ventilator. He immediately recognized his father's best friend. Bennett dug in and eventually identified a side effect of a drug that hadn't been well recognized. He saved her life. The drug was pulled from the market.

RADAR, whose research has been primarily funded by The National Institutes of Health, fo-cuses on hematology and oncology because that is Bennett's expertise. Bennett hopes his RADAR model will be adopted by researchers in cardiology, ophthalmology and other fields.

Researchers use MRI to predict recovery after spinal cord injuryOAK BROOK, Ill. -- Using magnetic resonance imaging (MRI), radiologists can better predict the likeli-hood of full or partial recovery of patients with acute spinal cord injuries (SCI), according to a study published in the June issue of the journal Radiology.

"Our study demonstrates that the possibility and extent of neurological recovery after SCI can be predicted within 48 hours after injury by rigorous assessment of MR images," said co-author Michael G. Fehlings, M.D., Ph.D., F.R.C.S.C., professor of neurosurgery at the University of Toronto and medical director at the Krembil Neuroscience Centre at Toronto Western Hospital. "In addition," Dr. Fehlings said, "these findings could result in a more aggressive clinical strategy for patients who may appear to have a severe SCI but may indeed have the capacity for substan-tial neurological recovery."

According to the National Spinal Cord Association, 250,000 to 400,000 people in the United States are living with SCI or spinal dysfunction. An estimated 7,800 new cases of SCI occur each year. Motor vehicle accidents account for 44 percent of these injuries in the U.S.

An initial MRI examination is typically performed on patients with SCI to determine the degree of neurological damage, as well as a possible prognosis. MRI findings may include cord hemor-rhage, swelling, soft tissue and ligament injury, blood clots or herniated discs.

Dr. Fehlings’ study included 100 patients with traumatic cervical SCI. The group consisted of 79 men and 21 women between the ages of 17 and 96. Complete motor and sensory SCI was seen in 26 patients, incomplete SCI was seen in 51 patients, and 22 patients were neurologically intact upon admission. One patient could not be classified. The majority of the patients had been injured in motor vehicle accidents.

MRI exams were obtained within 24 to 48 hours of injury. The research team studied three measurable imaging parameters: maximum spinal cord compression (MSCC), maximum canal compromise (MCC) and length of lesion (LOL). They also looked at other factors, including bleed-ing within the spine, swelling and soft tissue injury.

The results showed that severity of MSCC, bleeding and cord swelling were key indicators of a poor prognosis after SCI. Conversely, the absence of these symptoms indicated a good chance for neurological recovery even if the injury otherwise appeared severe.

"Since the severity of spinal cord compression is a predictor of outcome after SCI, this study suggests that MRI may predict which patients would benefit the most from decompressive surgery," Dr. Fehlings said.

He added that MRI should be performed on all patients with acute SCI whenever feasible as it provides information with prognostic value and serves to guide the clinician to optimize clinical care.

Turning Off Suspect Gene Makes Mice SmarterBy REUTERS

CHICAGO — Turning off a gene that has been associated with Alzheimer’s disease made mice smarter in the lab, researchers said Sunday.

The finding adds insight on learning and may lead to new drugs. The researchers said the mice were far more adept at sensing environmental changes than other mice.

“It’s pretty rare when you can make an animal smarter,” said Dr. James Bibb, assistant profes-sor of psychiatry at the University of Texas Southwestern Medical Center, who led the study pub-lished in the journal Nature Neuroscience.

Professor Bibb and colleagues used genetic engineering to breed mice that could be manipu-lated to switch off the gene, Cdk5, which controls a brain enzyme linked to diseases signaled by the death of neurons in the brain like Alzheimer’s.

“Any time we’re losing neurons, Cdk5 may be contributing to that process,” Professor Bibb said in a telephone interview. “That has made it an area of great interest. We have shown that we can turn off a gene in an adult animal. That has never been done before.”

When they tried to breed mice that lacked the gene, the pups died at birth. Professor Bibb said they tested the mice and found that the altered mice fared better than normal mice.

“Everything is more meaningful to these mice,” he said. “The increase in sensitivity to their surroundings seems to have made them smarter.”

Professor Bibb said the mice were better at tasks based on associated learning, adding:“It’s the most important kind of learning in the animal kingdom. It’s how we know where our

car is and that is our wife or our husband and that’s our kids. It’s how we connect things.”The smart mice performed better at learning to navigate a water maze and remembering that

they were given shocks when they were in a certain cage.“It was very clear right off the bat that the loss of Cdk5 made them have a much stronger as-

sociative memory,” Professor Bibb said.He said his work was inspired by the discovery in 1999 of Doogie mice, a smarter breed of

mice developed at Princeton University named after the television program “Doogie Houser, M.D.,” which featured a child prodigy.

Those mice were bred by manipulating NR2B, a gene that also has a role in associative mem-ory.

“It turns out Cdk5 was controlling the regulation of NR2B,” Professor Bibb said. “Maybe by finding these new mechanisms we can find new drugs that improve the cognitive performance of people who have deficits.”

He and colleagues are working on developing drugs that could create the same effect without needing genetic alteration.

But he said it was not clear what the long-term effects might be if such a drug were devel-oped, adding:

“If all of your synapses were magically strengthened all the time, that might be good for the short term. But I’m not sure if it would be good all the time.”

Nature’s Tricks Help Moths Say ‘Don’t Eat Me’By NICHOLAS WADE

The gaudy swirls of color on a butterfly’s wing, the rococo curlicues on its riotously dressed caterpillars, may seem to be delightful examples of nature’s artistry. But that is to miss nature’s point.

Every feature of a butterfly or moth, throughout its life from egg to adult, has been shaped over millions of years of evolution for specific purposes. Salient among these is escape from predators like birds, monkeys and the dreaded parasitic flies and wasps that lay their eggs inside the living caterpillar.

People arrived far too recently on the evolutionary scene for moths and butterflies to have anything to say to them. But after nearly 30 years of studying these insects in the Guanacaste conservation area of Costa Rica, Daniel Janzen has become an adept translator of their body language.

In two recent books, “100 Caterpillars” and “100 Butter-flies and Moths” (Harvard University Press, 2006 and 2007), he and Winifred Hallwachs, his colleague at the Uni-versity of Pennsylvania, explain the meaning of the exotic colors and camouflage patterns. The full-page color photo-graphs of each specimen were taken by Jeffrey C. Miller of Oregon State University.

The moth Calledema plusia never flies by day yet has learned how to imitate bright sunlight. A silvery gash on both sides of its brown wings, always folded over the body during daytime, mimics a shaft of light streaming through a dead leaf.

DISGUISES The mechanisms for warding off predators include dark coloring that allows the H. amphinome to blend in to tree bark. Jeffrey C. Miller/From “100 Butterflies and

Moths”Many butterflies have gashes of iridescent color splashed across their wings. Why risk such a

conspicuous display? The flashes of color accentuate the speed of flight. Their message to birds, Dr. Janzen suggests, is, “Don’t even try to catch me.”

Other bold color patterns, however elegant they may seem to people, are just toxic warning labels, real but often feigned, to would-be consumers.

Many butterfly and moth species try to pretend they are the least nutritious objects in the for-est. This generally means imitating a piece of bird excrement if one is a caterpillar, and a dead leaf when one reaches adulthood.

Another variation is for a caterpillar to sport a disconcerting pattern like a giant eye that can be winked at an aggressor.

A moth on which evolution has lavished a remarkable degree of protective care is Oxytenis modestia. The first four stages of its caterpillar mimic a bird dropping, complete with mock seeds. The fifth caterpillar stage performs a brilliant impersonation of a green snake, complete with a bulging head and two menacing faux eyes.

As an adult, the Oxytenis moth resembles a leaf, but even here evolution’s inventiveness is not an end. The moth breeds twice a year, and each form is different. The moths that hatch in the dry season are light beige, to resemble dry dead leaves, and those of the rainy season are dark and moldy looking.

Several butterflies practice a clever combination of camouflage and conspicuousness. Pieria helvetia has demure forewings and splashes of deep red on its hindwings. At rest, with its wings closed, it can hardly be seen. If disturbed by a predator, it darts into rapid flight, its red patches making it very visible. Then comes the disappearing act. It settles, quickly folds its wings and is invisible again.

Why do birds and monkeys go to such lengths to consume these in-sects, stimulating such a rich array of evolutionary strategies to evade capture? The answer is simple. Moths taste “like raw shrimp, if one should care to try,” Dr. Janzen assures the reader.BooksThe Brain: Malleable, Capable, VulnerableBy ABIGAIL ZUGER, M.D.Published: May 29, 2007

In bookstores, the science aisle generally lies well away from the self-help section, with hard reality on one set of shelves and wishful thinking on the other. But Norman Doidge’s fascinating synopsis of the current revolution in neuroscience straddles this gap: the age-old dis-tinction between the brain and the mind is crumbling fast as the power of positive thinking finally gains scientific credibility.The Brain That Changes ItselfStories of Personal Triumph From the Frontiers of Brain Science. By Norman Doidge, M.D. 427 pages. Viking. $24.95

The credo of this revolution is neuroplasticity ― the discovery that the human brain is as malleable as a lump of wet clay not only in in-fancy, as scientists have long known, but well into hoary old age.

In classical neuroscience, the adult brain was considered an im-mutable machine, as wonderfully precise as a clock in a locked case. Every part had a specific purpose, none could be replaced or repaired, and the machine was destined to tick in unchanging rhythm until its gears corroded with age.

Now sophisticated experimental techniques suggest the brain is more like a Disney-esque animated sea creature. Constantly oozing in various directions, it is ap-parently able to respond to injury with striking functional reorganization, and can at times actu-ally think itself into a new anatomic configuration, in a kind of word-made-flesh outcome far more characteristic of Lourdes than the National Institutes of Health.

So it is forgivable that Dr. Doidge, a Canadian psychiatrist and award-winning science writer, recounts the accomplishments of the “neuroplasticians,” as he calls the neuroscientists involved in these new studies, with breathless reverence. Their work is indeed mind-bending, miracle-making, reality-busting stuff, with implications, as Dr. Doidge notes, not only for individual pa-tients with neurologic disease but for all human beings, not to mention human culture, human learning and human history.

And all this from the fact that the electronic circuits in a small lump of grayish tissue are per-fectly accessible, it turns out, to any passing handyman with the right tools.Jacob Magraw

For patients with brain injury, the revolution brings only good news, as Dr. Doidge describes in numerous examples. A woman with damage to the inner ear’s vestibular system, where the sense of balance resides, feels as if she is in constant free fall, tumbling through space like an ocean bather pulled under by the surf. Sitting in a neuroscience lab, she puts a set of electrodes on the surface of her tongue, a wired-up hard hat on her head, and the feel of falling stops. The apparatus connects to a computer to create an external vestibular system, replacing her dam-aged one by sending the proper signals to her brain via her tongue.

But that’s not all. After a year of sessions with the device, she no longer needs it: her brain has rewired itself to bypass the damaged vestibular system with a new circuit.

A surgeon in his 50s suffers an incapacitating stroke. He is one of the first patients to enroll in a rehabilitation clinic guided by principles of neuroplasticity: his good arm and hand are immobi-lized, and he is set cleaning tables. At first the task is impossible, then slowly the bad arm re-members its skills. He learns to write again, he plays tennis again: the functions of the brain ar-eas killed in the stroke have transferred themselves to healthy regions.

An amputee has a bizarre itch in his missing hand: unscratchable, it torments him. A neurosci-entist finds that the brain cells that once received input from the hand are now devoted to the man’s face; a good scratch on the cheek relieves the itch. Another amputee has 10 years of ex-cruciating “phantom” pain in his missing elbow. When he puts his good arm into a box lined with mirrors he seems to recognize his missing arm, and he can finally stretch the cramped elbow out. Within a month his brain reorganizes its damaged circuits, and the illusion of the arm and its pain vanish.

Research into the malleability of the normal brain has been no less amazing. Subjects who learn to play a sequence of notes on the piano develop characteristic changes in the brain’s electric activity; when other subjects sit in front of a piano and just think about playing the same notes, the same changes occur. It is the virtual made real, a solid quantification of the power of thought.

From this still relatively primitive experimental data, theories can be constructed for the en-tirety of human experience: creativity and love, addiction and obsession, anger and grief ― all, presumably, are the products of distinct electrical associations that may be manipulated by the brain itself, and by the brains of others, for better or worse.

For neuroplasticity may prove a curse as well. The brain can think itself into ruts, with electri-cal habits as difficult to eradicate as if it were, in fact, the immutable machine of yore. Some-times “roadblocks” can be created to help steer its activity back in the desired direction (like bandaging the stroke patient’s good arm). Sometimes rewiring the circuits requires hard cere-bral work instead; Dr. Doidge cites the successful Freudian analysis of one of his patients.

And, of course, the implications for external re-engineering of the human brain are ominous, for if the brain is malleable it is also endlessly vulnerable, not only to its own mistakes but also to the ambitions and excesses of others, whether they are misguided parents, well-meaning cul-tural trendsetters or despotic national leaders.

The new science of the brain may still be in its infancy, but already, as Dr. Doidge makes quite clear, the scientific minds are leaping ahead.

Personal HealthFinding Some Calm After Living With ‘the Shakes’

By JANE E. BRODYAs Sandy Kamen Wisniewski remembers, her hands always shook.

She hid them in long sleeves and pockets and wrote only in block letters in school because at least that was readable. The tremor became much worse as she entered her teenage years, and if she was upset or under stress, it grew so bad she cringed with embarrassment and decided that it must all be psychological.

Ms. Wisniewski, now 40, was 14 when she learned that she had not an emotional disorder, but a neurological condition called essential tremor ― “essential” not because she needed it, but because no under-lying factor caused it. It was not a prelude to Parkinson’s disease, nor was it caused by a hormonal problem, a drug reaction or nervousness.

Stuart Bradford(Many people thought that Katharine Hepburn had Parkinson’s disease, when in fact she

shook because she had essential tremor, as does Terry Link, a state senator in Illinois, and Gov. Jim Gibbons of Nevada.)

This disorder, which in most cases is inherited, is so misunderstood and so often misdiag-nosed that Ms. Wisniewski, who lives in Libertyville, Ill., decided to write a book about it. Called “I Can’t Stop Shaking,” the book was self-published last year through Dog Ear Publishing in Indi-anapolis. Her intent is to help the estimated 10 million people who suffer with essential tremor, often for decades without knowing what is wrong.

John, for example, whose head shook uncontrollably, spent 27 years “being tested for nearly everything,” as he relates in the book. He even had an M.R.I. and was told by the doctor that there was nothing wrong with him.

Modern technology helped him learn the truth when he typed “head tremors” into a computer search engine and found the Web site for the International Essential Tremor Foundation. His shouts of joy upon recognizing his disorder woke his wife. He then recalled that his grandmother and all his cousins had what they called “the shakes,” also without knowing why.

Only a small minority of patients with essential tremor seek treatment, Ms. Wisniewski’s book says, although there are several medications that help and, for intractable cases, a surgical pro-cedure that can greatly reduce, if not eliminate, the tremors.

For Shari Finsilver, who never even told her parents about the hand tremors that began at age 11, the surgery she underwent in her 50s, called deep brain stimulation, was “a life-altering ex-perience, like someone awakened from a lifetime coma.”

As she wrote in Ms. Wisniewski’s book, “I immediately began doing all the things I had not been able to do for 40 years: write by hand, use a camera, cut with scissors, make change at the cash register, sign checks and credit card receipts, enroll in a public speaking course, dance with men other than my husband and son ― all the things most people take for granted.

“But best of all, I was able to walk down the aisle at my children’s weddings, and cradle my grandchildren in my arms with steady hands.”A Tremulous Mutation

One thorough study has indicated that in 96 percent of cases, essential tremor is familial, a result of an autosomal dominant genetic mutation. That means that every child of a person with the condition has a 50 percent chance of inheriting it. And most people, after learning the nature of their problem, are able to trace it from a parent and other family members. But the so-called penetrance of the mutated gene can vary widely, resulting in different degrees of disability.

The damaged gene interferes with voluntary muscles and can affect any body part, hands most often, but also the neck, larynx (resulting in a tremulous voice) and, less often, the legs. The tremor disappears at rest and during sleep, but becomes apparent when a person tries to do something with the affected part and is made worse by stress, fatigue, caffeine and anxiety.

In people with hand tremors, the shaking starts when they try to write or hold a cup of coffee or eat with a utensil. Many people with essential tremor devise ways to avoid such activities, like eating just sandwiches or never eating in public, typing instead of writing or paying by credit card to avoid writing a check.

One woman in Ms. Wisniewski’s book was able to return to college when she learned that dis-ability laws entitled her to a note taker for all her classes. But many employment opportunities are out of reach. Jean Moore worked in a payroll office until she could no longer read her own numbers. Another woman was fired from her job as a waitress when she could no longer carry cups of liquid and plates of food without spilling them.

Head tremor is more difficult to disguise. Some people sit with their elbows planted on a firm surface, holding their head in their hands.

While the disorder can show itself at any age, essential tremor usually does not become ap-parent until midlife and then worsens with age.Treatment Options

In diagnosing essential tremor, a doctor must first rule out other causes like medications, drug or alcohol withdrawal, excessive caffeine intake, overactive thyroid, heavy metal poisoning, fever and anxiety. A doctor also must check for other neurological conditions like Parkinson’s dis-ease, multiple sclerosis or dystonia.

A number of drugs have been found, mostly by accident, to relieve tremors. They include beta blockers like propranolol, marketed as Inderal, used mainly to control high blood pressure; primi-done, found in Mysoline; and topiramate, or Topamax, used mainly to treat epilepsy.

Several other drugs have helped some patients, and sometimes a combination of medications proves helpful. Dosages are limited by the patient’s ability to tolerate side effects. Injections of botulinum toxin A, in Botox, help many people with head tremors.

If drug treatment is not helpful, implanting a stimulator in the thalamus of the brain can block the nerve signals that cause tremors in the upper extremities. The procedure has its hazards and is usually a last resort.

Most people with essential tremor have discovered on their own that alcohol provides tempo-rary relief. But over time, more and more alcohol is needed to be helpful, so excessive intake and alcoholism are real dangers. This remedy is best used sporadically.

Members of the essential tremor foundation have provided a host of “survival” tips that Ms. Wisniewski lists in her book. They include these ideas:

* Using half-full mugs and holding them with all five fingers on the top.* Using a travel mug with a lid and straw.* Asking the server to deliver your plate with the food already cut in bite-size pieces.* Using a bib or fastening the napkin under your chin with a dentist’s chain.* Writing with a fat pen that has a rubber grip.* At the computer, wearing wrist weights and keeping palms anchored to the front of the key-

board.* Using an electric toothbrush and razor.* Using Velcro instead of buttons.* Carrying preprinted labels with your name, address and telephone number.For further information, including support groups for people with es-

sential tremor and their families, the foundation has a Web site at www.essentialtremor.org, and a toll-free telephone number, (888) 387-3667.

Planet hunters spy distant haulA haul of 28 new planets beyond our solar system has been de-

tected by the world's most prolific planet hunters.

The finds were among 37 objects seen orbiting distant stars by a US and Anglo-Australian team in the last year.

Other objects reported by the group, at an American Astronomical Society meeting in Hon-olulu, included five failed stars, known as brown dwarfs.

The finds increase the total number of known exoplanets to 236, more than half of which were discovered by the team.

"The more we look, the more we find planets," said Professor Tinney of the University of New South Wales, head of the Australian part of the Anglo-Australian Planet Search.

The ice-giant Gliese 436 is 30 light years from Earth"Super-Earth"

Among the finds were at least four multiple-planetary systems. All of the planets were so-called gas giants, similar to Jupiter, with no solid surface.

"Something like 10 to 15% of stars host gas giants," said Professor Tinney. "A larger fraction of stars may host planets too small for us to detect."

These could include Earth-sized objects, which could harbour life.Earlier this year, scientists using the European Southern Observatory (ESO) 3.6m Telescope in

Chile discovered the smallest exoplanet - as astronomers call planets that orbit a star other than the Sun - yet.

The "super-Earth" orbited the faint star Gliese 581, 20.5 light-years away in the constellation Libra. Its radius was just 1.5 times that of the Earth.

Intriguingly, the planet could have liquid water on its surface, a key ingredient of life.It was discovered using a sensitive instrument that can measure tiny changes in the velocity

of a star as it experiences the gravitational tug of a nearby planet.It was the same method used to detect the latest batch of extra solar planets.According to Dr Jason Wright of the University of California, Berkeley, one of the members of

the US California and Carnegie Planet Search, the technique has be-come more sophisticated, improving detection rates dramatically.

"We're just now getting to the point where, if we were observing our own Solar System from afar, we would be seeing Jupiter," he said.

These techniques allow scientists to detect changes in the motion of stars as small as one metre per second.

Astronomers are stuck with such indirect methods of detection because current telescope technology struggles to image very dis-tant and faint objects - especially when they orbit close to the glare of a star.

The smallest exoplanet discovered orbits Gliese 581Ice planet

The discovery of the 28 new planets has given astronomers new targets to analyse in more detail.

For example, a planet discovered two years ago has already yielded a mass of "extraordinarily rich" information, according to Professor Geoff Marcy of the University of California, Berkeley.

Circling the star Gliese 436, 30 light years from Earth, was an ice-giant planet that was calcu-lated by Swiss and Belgian scientists to be at least 22 Earth masses, slightly larger than the mass of Neptune.

Their studies had also revealed its density."It must be 50% rock and about 50% water, with perhaps small amounts of hydrogen and he-

lium," said Professor Marcy."This planet has the interior structure of a hybrid super-Earth/Neptune, with a rocky core sur-

rounded by a significant amount of water compressed into solid form at high pressures and tem-peratures."

However, the planet is not thought to be capable of supporting life.Decapitation and rebirth

Recently excavated headless skeleton expands understanding of ancient Andean ritualsImages of disembodied heads are widespread in the art of Nasca, a culture based on the

southern coast of Peru from AD 1 to AD 750. But despite this evidence and large numbers of tro-phy heads in the region’s archaeological record, only eight headless bodies have been recovered with evidence of decapitation, explains Christina A. Conlee (Texas State University). Conlee’s analysis of a newly excavated headless body from the site of La Tiza provides important new data on decapitation and its relationship to ancient ideas of death and regeneration.

As Conlee outlines in the June issue of Current Anthropology, the third vertebrae of the La Tiza skeleton has dark cut marks, rounded edges, and no evidence of flaking or breakage, indicating decapitation occurred at or very soon after the time of death. A ceramic jar decorated with an image of a head was placed next to the body. The head has a tree with eyes growing out of it, the branches encircling the vessel.

"Ritual battles often take place just before plowing for potato planting, and trees and un-ripened fruit figure in these rituals, in which the shedding of blood is necessary to nourish the earth to produce a good harvest," Conlee writes. "The presence of scalp cuts on Nasca trophy heads suggests the letting of blood was an important part of the ritual that resulted in decapita-tion."

Conlee also points to damage on the jar that indicates it had already been handled and used before being included in the tomb. This was only the third head jar found with a headless skele-ton. Most are found at domestic sites, and prior research has concluded that they were probably used to drink from, most likely in connection with fertility rituals. "If the head jar was used to drink from during fertility rituals, then its inclusion in the burial further strengthens the relation-ship between decapitation and rebirth," Conlee explains.

Notably, there is also no evidence of habitation in the La Tiza region during the Middle Nasca period (AD 450-550), to which the head jar dates. All of the Nasca domestic sites in the area date to the Early Nasca, indicating that the La Tiza skeleton may have been deliberately buried in an abandoned settlement that was associated with the ancestors.

"Human sacrifice and decapitation were part of powerful rituals that would have allayed fears by invoking the ancestors to ensure fertility and the continuation of Nasca society," Conlee writes. "The decapitation of the La Tiza individual appears to have been part of a ritual associ-ated with ensuring agricultural fertility and the continuation of life and rebirth of the commu-nity."

Evidence from ancient European graves raises questions about ritual human sacrifice

A fascinating new paper from the June issue of Current Anthropology explores ancient multiple graves and raises the possibility that hunter gatherers in what is now Europe may have practiced ritual human sacrifice. This practice – well-known in large, stratified societies – supports data emerging from different lines of research that the level of social complexity reached in the dis-tant past by groups of hunter gatherers was well beyond that of many more recent small bands of modern foragers.

Due to their number, state of preservation, richness, and variety of associated grave goods, burials from the Upper Paleolithic (26,000-8,000 BC) represent an important source of informa-tion on ideological beliefs that may have influenced funerary behavior. In an analysis of the Euro-pean record, Vincenzo Formicola (University of Pisa, Italy) points to a high frequency of multiple burials, commonly attributed to simultaneous death due to natural disaster or disease.

However, a look at grave composition reveals that some of the multiple burials may have been selective. Not only do the skeletons in these graves vary by sex and age, but the most spectacular sites also include a severely deformed individual with a pathological condition that would have been apparent since birth, for example, dwarfism or congenital bowing of the bones.

These multiple graves are also richly ornamented and in choice locales. For example, the re-mains of an adolescent dwarf in Romito Cave (Calabria, Italy) lie next to a female skeleton under an elaborate engraving of a bull. In the Sunghir double burial (Russia), the skeletons of a pre-teen boy and girl are surrounded by ivory objects including about 5,000 beads, each of which may have taken an hour to make.

"These findings point to the possibility that human sacrifices were part of the ritual activity of these populations and provide clues on the complexity and symbolism pervading Upper Pale-olithic societies as well as on the perception of "diversity" and its links to magical-religious be-liefs," Formicola writes. "These individuals may have been feared, hated, or revered . . . we do not know whether this adolescent received special burial treatment in spite of being a dwarf or precisely because he was a dwarf."

A new zest for life : How the treatment of common thyroid disease reduces tiredness and the risk factors for heart disease

New research from Newcastle University shows treatment for a shortage of the hormone thy-roxine lowers cholesterol, reverses weight gain and reduces the risk factors for heart disease.

Putting on weight and feeling lethargic?

Then new research from Newcastle University and funded by Gateshead Health NHS Founda-tion Trust shows it is worth having your thyroid levels checked – as these can be symptoms of thyroid disease which is easily identified and treated.

Known medically as sub clinical hypothyroidism, it is characterised by a shortage of the hor-mone thyroxine and often precedes an underactive thyroid.

It affects up to 16% of women and 6% of men, becoming more prevalent with age.The research has shown that treatment of subclinical hypothyroidism with thyroid hormone

reduces tiredness, cholesterol and reduces the risk factors for heart disease by improving the markers of atherosclerosis or hardening of the arteries.

In the study, patients undergoing 12 weeks of thyroxine treatment saw a reduction in their amount of LDL cholesterol, reversed weight gain - losing on average half a kilo, felt less tired and had reduced their risk factors for heart disease.

Until recently many doctors considered this condition not worthy of treatment. Now a new study led by Dr Jolanta Weaver of Newcastle University and Gateshead Health NHS Foundation Trust published in this month’s issue of The Journal of Clinical Endocrinology and Metabolism shows that treatment leads to significant improvements for patients.

In the largest trial to date, 100 participants with persistent subclinical hypothyroidism were given thyroxine and compared with those taking a placebo or dummy medication.

Dr Salman Razvi and Dr Jolanta Weaver of Newcastle University’s School of Clinical Medical Sciences carried out a pivotal crossover study. They assessed common heart disease risk factors such as the level of LDL, or “bad”, cholesterol, body weight and endothelial function, which is a very early marker of hardening of the arteries. They also asked participants to rate their quality of life.

This treatment did not cause any side-effects.Dr Weaver says, “The results of our study show that treatment of people with this mild form of

underactive thyroid condition leads to significant improvements in risk factors for ischemic heart disease and symptoms of tiredness.”

Patients with subclinical hypothyroidism are being encouraged to discuss their treatment with their doctors.CASE STUDY

Frances King, 56, from Dunston, Gateshead.“I took part in the study because I was first diagnosed with a borderline underactive thyroid

27 years ago but never had any treatment. I‘d never been ill but always had a lack of energy and generally felt tired and lethargic. As soon as I was put on the medication I noticed a difference. Since the trial I’ve been back to my GP and have been prescribed thyroxine. I now have more en-ergy and feel brighter.

I’ve battled with my weight for years but since getting the medication I’ve lost a couple of stones because I’m more motivated to do things. I’ve got a real zest for life - I run up the stairs, I’ve got the energy to walk the dogs and I’m out gardening which I hadn’t been doing.”Yin and yang -- Balance could play key role in progression of Alzheimer's dis-

easeTroy, N.Y. -- Researchers at Rensselaer Polytechnic Institute are challenging current thinking on the causes and prevention of Alzheimer’s disease, offering a new hypothesis that could be the key to preventing this form of dementia. The researchers have found that a specific imbalance between two peptides may be the cause of the fatal neurological disease that affects more than five mil-lion people in the United States.

"We have found that two peptides, AB42 and AB40, must be in balance for normal function," said Chunyu Wang, lead re-searcher and assistant professor of biology at Rensselaer. "They are like the Yin and Yang in Taiji, an ancient Chinese philoso-phy. When the peptides are produced in the correct proportions, the brain is healthy; but when that delicate balance is changed, pathological changes will occur in the brain and the person’s memories be-come hazy, leading to eventual dementia."

As levels of AB40 decrease, levels of harmless AB42 monomers decrease as the monomers form harmful oligomers Rensselaer Polytechnic Institute/Yilin Yan

Wang expects that this imbalance could be the main factor in the progression of Alzheimer’s disease. If correct, the addition of AB40 may stop the disease’s development. Wang notes that further research is needed, but his preliminary results challenge the current mode of thinking about how these peptides contribute to the progression of the disease.

The research will be published in the June edition of the Journal of Molecular Biology.Peptides are formed by the linking of different amino acids. The two peptides that Wang inves-

tigated were both Amyloid B-peptides (AB) — specifically those composed of 40 and 42 amino acids, called AB40 and AB42. These two peptides have been previously found in deposits, called senile plaques or amyloid plaques, in brains afflicted with Alzheimer’s disease. These plaques, mainly composed of AB42 fibrils, are a hallmark of Alzheimer’s disease.

Prior research has uncovered that increased levels of AB42 become toxic to brain cells when individual molecules of AB42, or monomers, combine to form oligomer or fibril chains. This process is called aggregation. But the role of AB40, which is also found in senile plaques and generated from the same protein as AB42, has not been clearly estab-lished. Wang set out to determine what role this peptide played in the generation of AB42 aggregates.

Wang used the advanced Nuclear Magnetic Resonance (NMR) machines within Rensselaer’s Center for Biotechnol-ogy and Interdisciplinary Studies to monitor the formation of harmful AB42 fibrils in the presence of different levels of AB40. NMR is an extremely powerful research tool capable of characterizing the three-dimensional structure and dy-namics of biological molecules.

Using NMR data, Wang found that as AB40 levels in-creased, the aggregation of AB42 fibrils sharply decreased, protecting benign AB42 monomers.

Researchers believe an imbalance of peptides leads to Alzhiemer’s progression. Rensse-laer Polytechnic Institute/Caitlin Piette

"We have found that the ratio of AB40 to AB42 plays a key role in AB42 aggregation," Wang said. "The current mode of thinking in Alzheimer’s emphasizes the toxic role of AB42 but ne-glects the protective role of AB40. Combined with previous work on AB40 by many other groups, our data suggest that AB40 has an equally important, protective role in Alzheimer’s. Thus AB42, the bad molecule, and AB40, the good molecule, are like Yin and Yang in Taiji. The brain can only function normally when they are in balance."

Wang’s experiments show that when there is 15 times more AB40 than AB42, the formation of AB42 fibrils is almost completely stopped. "This means that the introduction of AB40 to tip the peptide balance toward AB40 could potentially halt or slow down the progression of the Alzheimer’s in the human brain," Wang said.

Wang plans to continue investigating how AB40 halts the formation of AB42 fibrils, and he al-ready sees vast implications for this change in thinking about the progression of the disease.

"This has the potential to become a simple therapy to prevent the formation of toxic AB42 species," he said. "I plan to continue my research on the role of AB40 and hope that we can test this theory on human neurons, animal models, and someday in clinical trials. One critical advan-tage of using AB40 for the prevention or therapy for Alzheimer’s is that AB40 is already known to be largely free of side effects at near physiological concentration."

-------------------------The research was funded by the Alzheimer’s Association and a New York State Office of Science, Technology, and Academic Research (NYSTAR) James D. Watson Investigator Program Award.Rensselaer graduate student Yilin Yan worked with Wang on the research project.

New study suggests potential for a broadly-protective HIV vaccineUSU researchers find broad-spectrum defense against multiple strains of HIV-1

BETHESDA, Md. -- New research conducted at the Uniformed Services University of the Health Sci-ences (USU) suggests that it may be possible to develop a vaccine that protects against the myr-iad strains of the HIV virus. HIV is extremely variable, so an effective vaccine may need to stimu-late the body to produce cross-reactive antibodies that will neutralize multiple viral strains. These results demonstrate that induction of truly broad-spectrum neutralizing antibodies may be an achievable goal. This groundbreaking study titled: “Extensively Cross-Reactive Anti-HIV-1 Neutralizing Antibodies Induced by gp140 Immunization” appears this week in the Early

Edition of Proceedings of the National Academy of Sciences http://www.pnas.org/papbyre-cent.shtml.

To be effective, an HIV vaccine must induce the body to produce cross-reactive antibodies that can neutralize multiple strains. USU Professors CAPT Gerald Quinnan, Jr., M.D., USPHS, and Christopher Broder, Ph.D., and their colleagues at USU attempted to elicit these broad-range an-tibodies in an animal model by immunizing with a particular HIV-1 surface protein, designated R2 gp140, and an immune response-boosting component. The researchers tested antibodies gener-ated by the immunizations to determine their effectiveness in neutralizing the infectivity of a va-riety of HIV-1 strains. Antibodies produced as a result of immunization neutralized all 48 strains of HIV-1 tested. The results are encouraging for vaccine development, because they showed that it is possible to elicit a broad-spectrum antibody response.

Genes may help people learn Chinese* 22:00 28 May 2007

* NewScientist.com news service* Nora Schultz

All babies can grow up speaking any language, but now researchers have uncovered evidence that genes may in fact play a part in learning so-called "tonal languages", such as Chinese.

Subtle pronunciation differences in tonal languages can radically change the meaning of words, which may be one reason why such languages are so hard to learn for speakers of non-tonal languages like English. So for a non-native Chinese speaker, to enquire after the health of someone’s mother might easily result in a query about the wellbeing of their horse.

And now it appears that there may after all be something in our genes that affects how easily tonal languages can be learned. Such are the findings of Dan Dediu and Robert Ladd of Edin-burgh University, UK, who have discovered the first clear correlation between language and ge-netic variation.

Using statistical analysis, the pair showed that people in regions where non-tonal languages are spoken are more likely to carry different, more recently evolved forms of two brain develop-ment genes, ASPM and Microcephalin, than people in tonal regions. Dediu and Ladd accounted for geography and history, and the gene differences remained.

Bernard Crespi, an evolutionary biologist at Simon Fraser University in Burnaby, Canada, says the results "open up a whole new field of

inquiry, that links language evolution with adaptive molecular evolution and brain function."No genetic advantage

Since both genes function in brain development, Dediu and Ladd propose that they may have subtle effects on the organisation of the cerebral cortex, including the areas that process lan-guage.

It is already known that brain anatomy differs between English speakers who are good at learning tonal languages and those that find it harder, says Ladd, who now wants to see whether similar differences can be found between individual carriers of the ASPMand Microcephalin vari-ants.

A remaining puzzle is the role of natural selection. It has been argued that the newer variants of these two genes are positively selected, but so far nobody has been able to show how they might provide a selective advantage.

Dediu and Ladd do not think the genes' link to tonality could be the answer. "There is abso-lutely no reason to think that non-tonal languages are in any way more fit for purpose than tonal languages," says Ladd. "Chinese society developed advanced technology, politics and philoso-phy with a tonal language just as successfully as roughly contemporary eastern Mediterranean societies with non-tonal languages."

But Crespi speculates that the lower complexity of non-tonal languages could confer a selec-tive advantage: "Adoption of a simpler language might be 'easier', allowing for faster acquisition of language or other brain functions in early childhood. These ideas could be tested."Journal reference: Proceedings of the National Academy of Sciences (DOI: 10.1073/pnas.0610848104)

Human antibodies successfully treat bird flu* 01:00 29 May 2007

* NewScientist.com news service* Clare Wilson

"Immortalised" blood cells from two Vietnamese patients who survived a brush with bird flu may provide a way to cure people of the infection, rather than just reduce its severity.

Antibodies made from the patients’ blood cells grown in the lab have cured mice infected with the H5N1 bird flu virus, suggesting they might make an effective treatment or preventive ther-apy for humans.

The antibodies worked well when administered three days after the mice were infected, with all 20 mice in the treatment groups surviving, compared with none out of five in the control group. The antibodies also worked as a preventive therapy when given before the mice were in-fected.

The researchers, from the Hospital for Tropical Diseases in Ho Chi Min City, isolated four blood-cell lines that produced antibodies effective against bird flu from Vietnam - three of these also worked against samples taken from Indonesia, home to the other main strain of H5N1 virus found in Asia.No guarantee

At the moment, antiviral drugs such as Tamiflu are the best treatment and prevention against bird flu. But, although these drugs improve survival rates, they do not guarantee a cure, and there have already been a few cases of virus resistant to Tamiflu.

The new antibody treatment could be used together with antivirals: “What we are trying to do is add another arrow to the quiver of options for treating patients with H5N1 infection," says Cameron Simmons, who led the study.

“If it works after three days, that’s very good news,” says Albert Osterhaus, a bird flu expert at Erasmus University in Rotterdam, the Netherlands. “It means you could use it after the first symptoms.”Costly production

Other groups have produced antibodies effective against bird flu made from animal blood cells. This study is the first to use antibodies from human survivors of H5N1.

Compared with drugs, however, antibodies could be costlier and harder to mass produce in the face of a pandemic. They might be of most use in treating the few people who catch the dis-ease directly from birds, and for localised outbreaks. This could help prevent wider outbreaks.

"This is not a tool for public-health-level control of H5N1," says Simmons. "It could be useful in the sort of setting at the moment where we have low levels of infection." Another drawback is that the antibodies may not be effective if the virus mutates.

H5N1 is affecting poultry in several Asian countries, and so far has caused 306 cases in hu-mans, almost two-thirds of which were fatal. All of the victims seem to have been infected after close contact with diseased birds. But experts fear that if the virus changes so that it is more easily transmitted between humans, it could cause a global pandemic.

A crude form of antibody therapy was used in the 1918 flu pandemic, which killed 50 million people worldwide. Doctors gave patients infusions of serum, the liquid portion of blood, taken from people who had recently been infected and survived. A recent study suggests it halved the death rate, from 37% to 16%.Journal reference: PloS Medicine (vol 4, p 178)

Common gene mutation heightens breast cancer risk* 14:09 29 May 2007

* NewScientist.com news service* Roxanne Khamsi

A common gene mutation found in one out of six women carries a 60% increased risk of breast cancer, a large new analysis reveals.

Researchers surveyed DNA samples from nearly 50,000 women – half of whom had breast cancer – looking for genes that may incur only small increases in breast cancer risk, but which are carried by a large proportion of the population.

They say that the newly identified gene variant – in the gene called fibroblast growth factor receptor 2 (FGFR2) – is the most important genetic risk factor for breast cancer identified in about a decade, due to its widespread prevalence.New biological pathway

Douglas Easton at the University of Cambridge, UK, and colleagues who carried out the DNA analysis, looked specifically for small changes in the genetic code known as single nucleotide polymorphisms (SNPs) associated with breast cancer.

The team found that women who carry one faulty copy of FGFR2 appear to have a 20% ele-vated risk of breast cancer, while those with two altered versions – one in six women – face up to a 60% greater chance of the illness.

"This is probably the most important paper on breast cancer genetics since the cloning of BRCA2 in 1995," says Georgia Chenevix-Trench at the Queensland Institute of Medical Research in Australia, who collaborated with Easton on the new study.

A second group has also found a similar link between FGFR2 and cancer among women en-rolled in the US-based Nurses' Health Study.

"This finding opens up new avenues of research into the causes and prevention of breast can-cer by identifying a new biological pathway relevant to risk of the disease," says David Hunter of the Harvard School of Public Health in Boston, Massachusetts, US, who contributed to both new studies."Premature" to screen

Scientists have already identified other genes that contribute to the risk of breast cancer. For example, somewhere between 50% to 85% of women who have mutations in the BRCA1 and BRCA2 genes will develop this disease at some point in their lives, according to Cancer Research UK.

But experts estimate that BRCA1 and BRCA2 account for only 25% of the breast cancer cases caused by hereditary factors. Moreover, these genes appear to influence DNA repair.

FGFR2 is different in that seems to relate more to cell growth or cell signalling, scientists say."We're very excited by these results because the regions we identified don't contain previ-

ously known inherited cancer genes," says Easton. "This opens the door to new research direc-tions."

Researchers hesitate to advocate testing women for the FGFR2 gene. Hunter believes that "it is premature to recommend screening women for these variants" until scientists know more about other genetic risk factors.

In the meantime, the new genetic insights into breast cancer may help scientists develop new drugs to treat these tumours. Journal reference: Nature (DOI: 10.1038/nature05887) and Nature Genet-ics (DOI: 10.1038/ng2075)

The Dirty Water UndergroundBy GREGORY DICUM OAKLAND, Calif.

LAURA ALLEN’S modest gray house in the Oakland flatlands would give a building inspector nightmares. Jerry-built pipes protrude at odd angles from the back and sides of the nearly cen-tury-old house, running into a cascading series of bathtubs filled with gravel and cattails. White PVC pipe, buckets, milk crates and hoses are strewn about the lot. Inside, there is mysterious — and illegal — plumbing in every room.

Ms. Allen, 30, is one of the Greywater Guerrillas, a team focused on promoting and installing clandestine plumbing systems that recycle gray water — the effluent of sinks, showers and washing machines — to flush toilets or irrigate gardens.

To her, this house is as much an emblem of her belief system as a home. Although gray water use is legal in California, systems that conform to the state’s complicated code tend to be very expensive, and Ms. Allen and her fellow guerrilla, Cleo Woelfle-Erskine, are out to persuade the world that water recycling can be a simple and affordable option, as well as being a morally es-sential one.

They are part of a larger movement centered in the West — especially in arid regions like Ari-zona, New Mexico and Southern California — that includes both groups that operate within the law and ones that skirt it. The goal is the reuse of home gray water as a way to live within the re-gion’s ecological means. Using their own experience and contributions from others, they have just published a do-it-yourself guide to gray water systems that is also a manifesto for the move-ment, “Dam Nation: Dispatches From the Water Underground.”

“A lot of people that care about water try to conserve it,” said Ms. Allen, an elementary-school teacher who installed several gray water systems after buying this home — which she named the “Haut House,” for House of Appropriate Urban Technology — four years ago with a house-mate. “But this is about changing the way you interact with it.”

Mr. Woelfle-Erskine, a writer and teacher who lives on a houseboat with a gray water system in San Pablo, Calif., 10 miles north, added, “It’s about trying to use resources to their full poten-tial and interact with ecosystems in a beneficial way.”

In 1994, California became the first state to establish guidelines for gray water use — as most other states have since — and it has become a leader in building industrial-scale gray water sys-tems. The town of Arcata, for example, has an extensive system that serves the entire popula-tion of 17,000, and even the state’s oil refineries have gray water systems.

But many gray water advocates say that California’s plumbing code — which stipulates things like pipe sizes, burial depths and soil tests based on rules established for septic systems — is prohibitively complicated for private homeowners interested in recycling gray water, and that its requirements are prohibitively expensive.

“The code is so overbuilt that I’m beginning to think it’s better to just have everyone do it bootleg,” said Steve Bilson, the founder of ReWater Systems, a company that has installed around 800 code-compliant gray water systems at a cost of about $7,000 each, and who worked as a consultant on California gray water legislation in the 1990s.

As a result, many homeowners have installed unpermitted, illegal plumbing, relying on tech-niques developed by covert researchers like the Greywater Guerrillas. (It is difficult to know how many, since these systems are not registered with any government or organization, but Ms. Allen said that based on her observations there are probably around 2,000 homes equipped with gray water systems, a few legal but most illegal, in the Bay Area alone.)

On a recent afternoon, Mr. Woelfle-Erskine stood in the backyard of the Haut House and ex-plained how one of the half-dozen gray water systems there works. A pipe running from the house deposits shower and sink water into an elevated bathtub in the yard that is filled with gravel and reeds, and the roots of plants begin filtering and absorbing contaminants. The water then flows into a second, lower, tub, also containing a reedbed, before flowing into a still-lower tub of floating water hyacinths and small fish.

“We’ve had the water tested,” Mr. Woelfle-Erskine said, “and it’s clean — there’s just a little phosphorous left, which the plants in the garden actually like.” Through trial and error, Mr. Woelfle-Erskine and Ms. Allen have found what they say is the best way to spread wastewater into the gravel beds (through a screened milk crate) and which plants best clean the water while not growing so vigorously as to block pipes (cattails).

Although this Rube Goldberg setup, known as a constructed wetland, cost only about $100 to build, it represents a pinnacle of gray water system design, which is usually far more modest, ac-cording to Art Ludwig, an ecological systems designer in Santa Barbara. (Mr. Ludwig’s Web site, graywater.net, offers a practical introduction for do-it-yourselfers.) The vast majority of systems, Mr. Ludwig said, “cost less than a hundred bucks — it can be just a hose.” For example, a hose connects the sink to the toilet tank to create a gray-water toilet in one of the Haut House bath-rooms.

In spite of the ad hoc nature of many illegal systems, Mr. Ludwig said, he has “never heard of a single case of health problems from using gray water, ever.” Similarly, Simon Eching, the chief of program development at California’s Department of Water Resources — the body that drafted the state’s gray water code — said he knew of no health issues arising from gray water use in California.

But Mr. Ludwig’s Web site also points out that there are a number of potential pitfalls. He strongly discourages ponds of exposed water like the one fed by the constructed wetland in Ms. Allen’s backyard, for example, because they can draw mosquitoes that carry disease. He cau-tions against crossing plumbing lines and contaminating clean water; using gray water in sprin-kler systems or on fruits and vegetables that are eaten raw (it should only be used to irrigate roots); and allowing water contaminated by toxic cleansers, soiled diapers or contact with people who have infectious diseases to enter the gray water system.

Not even the Greywater Guerrillas would now condone the first system they built, in 1999. Back then, they were living with six housemates in a rented house in a rundown part of Oakland.

After receiving a water bill showing that the house was using 241 gallons a day despite their conservation efforts (the figure was actually less than half the national average of 70 gallons per person per day), the two headed to the basement with little more than a hacksaw and righteous enthusiasm. “We didn’t have a plan,” Ms. Allen said, “and we didn’t even have the materials. We were dumb, really.”

Their initial efforts dumped used shower water into the basement, forcing their housemates to forgo bathing for days. But before long, they were building a gray water system.

Two years later, as the Guerrilla Greywater Girls (at the time, Cleo Woelfle-Erskine was a woman) they published a “Guide to Water,” a crude sheaf of photocopies held together with a rubber band that combined plumbing instructions and design tips with an argument that water systems like dams and aqueducts were instruments of greed. “Dam Nation” is an expanded and less breathless descendant of the guide, with contributions from movement members as far away as Thailand.

Thousands of copies of the original were circulated while the Greywater Guerrillas honed their skills up and down the West Coast, installing systems from Seattle to Los Angeles for friends and like-minded people, and occasionally for hire, and connecting interested homeowners with plumbers willing to do illegal work. (Ms. Allen even took a plumbing course at a community col-lege; she said that when the instructor began to sense what she was up to, he stopped answer-ing her questions.)

Four years ago, they worked with Babak Tondre, a co-founder of a demonstration home in Berkeley called EcoHouse, to install a gray water system there.

“When the Greywater Guerrillas came over, I didn’t really know what I was getting into,” said Mr. Tondre, 37. He was soon forced to remove the system when the nonprofit Berkeley Ecology

Center, which runs the house, objected: “The board flipped when they saw it. It was totally ille-gal.”

Mr. Tondre then applied for a permit from the city. The resulting system, a more robustly engi-neered constructed wetland, funnels shower and laundry water underground, through a deep bed of gravel contained within a pond liner, and into a pipe at the other end of the gravel bed. More buried pipes direct water to the roots of plum, pear and cherry trees.

The system — which Mr. Tondre believes is the first and so far only residential constructed wetland in California built with a permit — cost $4,000 using volunteer labor. It can convert a maximum of 27,000 gallons of gray water into irrigation every year, enough for six fruit trees, along with the marsh plants in the wetland itself.

If gray water is starting to gain public acceptance, the Greywater Guerrillas are staying well ahead of the mainstream. At the side of the Haut House, next to a chicken coop, twin plastic bar-rels hold hundreds of pounds of waste from composting toilets inside the house.

While chickens pecked around her bare feet, Ms. Allen plunged a giant corkscrew into one of the barrels to mix the contents and speed the yearlong composting process. “Smell it,” she said. “Not bad at all.”

XO-3b: Supersized planet or oasis in the 'brown dwarf desert'?Amateur, professional astronomers find one of the oddest planets on record

The latest find from an international planet-hunting team of amateur and professional as-tronomers is one of the oddest extrasolar planets ever cataloged -- a mammoth orb more than 13 times the mass of Jupiter that orbits its star in less than four days.

Researchers from the U.S.-based XO Project unveiled the planet, XO-3b, at today's American Astronomical Society meeting in Honolulu. Christopher Johns-Krull, a Rice University astronomer and presenter of the team's results, said, "This planet is really quite bizarre. It is also particularly appropriate to be announcing this find here, since the core of the XO project is two small tele-scopes operating here in Hawaii."

"Of the 200-plus exoplanets found so far, XO-3b is an oddity in several respects," said XO Project director Peter McCullough, an astronomer at the Space Telescope Science Institute in Bal-timore. "It's the largest and most massive planet yet found in such a close orbit, and given the proximity of the orbit to the star, we were surprised to find that the orbit is not circular but sig-nificantly elliptical."

Given all its eccentricities, XO-3b is likely to pique the interest of astronomers who study planet formation, McCullough said.

"We are intrigued that its mass is on the boundary between planets and 'brown dwarfs,'" Johns-Krull said, "There's still a lively debate among astronomers about how to classify brown dwarfs." Any stellar mass that's large enough to fuse hydrogen -- anything more than about 80 Jupiter masses -- is a star. Brown dwarfs are massive objects that fall short of being stars.

"The controversy lies at the lower end of the scale," said Johns-Krull, an assistant professor of physics and astronomy at Rice. "Some people believe anything capable of fusing deuterium, which in theory happens around 13 Jupiter masses, is a brown dwarf. Others say it's not the mass that matters, but whether the body forms on its own or as part of a planetary system."

By virtue of their mass, any planet big enough to contend for brown dwarf status should be easy for most planet hunters to spot. That's because astronomers don't actually look for planets when they scan the sky; they generally look for stars that wobble due to the gravitational pull of planets orbiting around them. The larger the planet, the more wobble it creates, so planet hunters using this "radial velocity" method expected to find a lot of brown dwarfs when they started scanning the sky for wobbling stars a decade ago. That hasn't happened, and the dearth of supersized objects has become known in the field as the "brown dwarf desert."

What also makes XO-3b intriguing is the fact that it's a "transiting planet," meaning it passes in front of its star during each orbit. Fewer than two dozen transiting planets have been identi-fied, and XO-3b is the third found by the XO Project, which was designed specifically to look for them.

The XO Project benefits from its partnership between professional and amateur astronomers. The XO Project begins its search with a telescope located on Haleakala summit operated by the Institute for Astronomy of the University of Hawaii. The telescope is created from two commer-cially available 200-millimeter telephoto camera lenses. Using the Haleakala telescope, XO's pro-fessional team first identifies candidate stars that dim ever so slightly from time to time. XO's amateur astronomers observe these candidates over time and look for further evidence that the dimming is due to a transiting planet. Once enough evidence is in place, the professional team uses large telescopes -- the 2.7-meter Harlan J. Smith Telescope and the 11-meter Hobby-

Ebberly Telescope, both at the University of Texas McDonald Observatory in West Texas -- to confirm the presence of a transiting planet.

"There are many astrophysical systems out there that mimic transiting planets," McCullough said. "The only way to sort out the real planets from the rest is to observe the stars more care-fully. Observation time on big telescopes is scarce, and that's where our amateur partners come in, culling our long lists of candidates down to more manageable size to observe with the big telescopes. The XO Project benefits enormously from the clear skies of Haleakala and the avail-ability of telescopes such as the Hobby-Ebberly, Spitzer, and Hubble and their capable staffs that operate them. The global reach and dedication of our amateur collaborators is especially note-worthy.

"I like to point out that Olympic athletes are amateurs too," McCullough said.UCL scientist develops a measure of distraction

A scientific indicator of how easily distracted you are has been designed by a UCL (University College London) psychologist. It could be used as another assessment tool during the recruit-ment process and would have particular benefits in fields where employee distraction could lead to fatal errors.

People who are more easily distracted are at greater risk of being involved in accidents. Pro-fessor Nilli Lavie, UCL Psychology, who led the research published today in the Association for Psychological Science journal, said: "When you are easily distracted, you are more liable to do things like put your keys in the fridge or call out 'come in' when answering the phone. These are the more amusing consequences of distraction but distraction can have more serious implica-tions. For example, it is known to be associated with a higher risk of being involved in various types of accidents such as car and workplace accidents."

Some jobs – such as bus driver or pilot – put the employee in situations where the potential for distraction is very high and yet focused attention is crucial. This computer-based test, which measures subjects' accuracy and reaction times when they are exposed to distractions, would effectively filter out any candidates who were easily distracted.

Professor Lavie said: "This test could act as another form of psychometric testing for employ-ers who want to know how focused the staff they are hiring are likely to be. Some jobs can be undertaken very well even if you are prone to being distracted. For example, you can be a great scientist or writer and still be absent-minded! But there are many areas where productivity criti-cally depends on the ability of staff to stay focused, yet current psychometric tests do not mea-sure it."

This test correlates with responses given to the 'Cognitive Failures Questionnaire', which pre-dicts a person's level of distractibility provided that the subject answers honestly. The questions include: "How often do you find you accidentally throw away the thing you want and keep what you meant to throw away – as in the example of throwing away the matchbox and putting the used match in your pocket""

Professor Lavie said: "Relying on questionnaires to assess how easily distracted potential em-ployees might be obviously has its downsides – people are not always honest about their nega-tive attributes during interviews.

"People come away from our test thinking they've done really well and haven't been dis-tracted at all when in fact their response times increase and they tend to make more mistakes; showing that they have been distracted. So the test is objective and there's no way of doctoring the results."

61 subjects took a short computerised test during which letters, acting as distractions, flashed up on screen. The test involves finding the odd-one-out in a circular display of letters. For exam-ple, subjects had to find the letter X amongst similar letters such as H, M, K and Z; or, in the eas-ier task, a letter X or N among Os. At the same time, letters were flashed on-screen outside the circle of letters to distract the participant from their task. Subjects were asked to ignore the dis-tracter letters and focus on the odd-one-out in the circle of letters. They had to rapidly press the relevant key on a keyboard when they located the odd-one-out. This measures reaction times and the effects of distracters on performance.

The second finding in the paper showed that all people – whether they are generally easily distracted or not – were far less distracted when they were performing the more difficult task. Because the brain was loaded with information that was relevant to the task, there was no extra brain capacity for processing distracting information and so even people who are more easily distracted are able to focus all their attention on the task in hand.

Professor Lavie said: "This second finding shows that, even if you are more easily distracted than others, you can decrease your susceptibility to being distracted. This could have important implications for increasing attention and performance. I am currently working on specific applica-

tions for education that aim to improve attention in school pupils and reduce the likelihood of them being distracted both in class and when doing homework. We could make commercial ap-plications of the distraction test available on demand."

An 'elegant' idea proves its worth 25 years laterThe simple notion of copying the body’s own natural "waste disposal" chemistry to mop up po-

tentially toxic nitrogen has saved an estimated 80 percent of patients with urea cycle disorders --- most of them children – according to a report in this week’s New England Journal of Medicine summarizing a quarter century of experience with the treatment.

The effectiveness of sodium phenylacetate and sodium benzoate, two chemicals the body al-ready makes to carry nitrogen for disposal in urine "just knocked my socks off from the moment we first tried them," recalls Saul Brusilow, M.D., professor emeritus of pediatrics at Hopkins who first had the notion to use the drugs. "In all my years I never came across another disease where patients come in near-comatose and you stick a needle in them and lo and behold, they wake up—just like that. It was just astonishing," he says.

"His elegant idea was to give patients chemicals they already make in small amounts in large doses to make up for the missing urea cycle enzyme they inherited," says Ada Hamosh, M.D., M.P.H, clinical director of the McKusick-Nathans Institute of Genetic Medicine. "Sodium phenylac-etate and sodium benzoate already know how to eliminate nitrogen in urine, so having more in the body carries more nitrogen out and reduces the toxic effects of excess nitrogen accumula-tion."

Excess nitrogen yields ammonia, which is poisonous and in the case of urea cycle disorders, causes brain damage, retardation, coma and even death.

Despite the immediate clinical success of the treatment, the drug combination was finally ap-proved by the U.S. Food and Drug Administration only in 2005.

Brusilow, Hamosh, and colleagues at Stanford University, University of Minnesota, Thomas Jefferson University and the Medical College of Wisconsin looked back at 299 urea cycle disorder patients with a total of 1,181 hyperammonemia "episodes" from 118 hospitals around the United States from August 1980 until March 2005.

The regimen consisted of high-dose intravenous sodium phenylacetate and sodium benzoate for two hours followed by "maintenance infusions" until blood ammonia levels were normal. The patients’ overall survival rate was 84 percent, and 96 percent survived episodes of severe am-monia poisoning.

An estimated one in 40,000 live births is a child with a urea cycle disorder, according to Hamosh, who says early and accurate detection can now assure prompt treatment.

"We’re teaching all medical students at Hopkins to consider hyperammonemia and immedi-ately do blood tests when they see a combative, lethargic or comatose newborn or child," she says. "The longer the hyperammonemia lasts, the higher the risk for brain damage."

"This is a happy story," says Brusilow. "It isn’t too often in genetic medicine that we can intu-itively develop a treatment with already available chemicals and save lives."

Detecting cold, feeling pain: Study reveals why menthol feels freshScientists have identified the receptor in cells of the peripheral nervous system that is most

responsible for the body's ability to sense cold.The finding, reported on-line in the journal "Nature" (May 30, 2007), reveals one of the key

mechanisms by which the body detects temperature sensation. But in so doing it also illuminates a mechanism that mediates how the body experiences intense stimuli – temperature, in this case – that can cause pain.

As such, the receptor – known as menthol receptor TRPM8 -- provides a target for studying acute and chronic pain, as can result from inflammatory or nerve injury, the researchers say, and a potential new target for treating pain.

"By understanding how sensory receptors work, how thresholds for temperature are deter-mined, we gain insight into how these thresholds change in the setting of injury, such as inflam-matory and nerve injury, and how these changes may contribute to chronic pain," says senior author David Julius, PhD, chairman and professor of physiology at UCSF.

The methanol receptor, and other temperature receptors discovered in recent years by the Julius lab, offer potential targets for developing analgesic drugs that act in the peripheral, ner-vous system, rather than centrally, where opiate receptors act, he says.

The finding is a milestone in an investigation the team began several years ago. In 2002, the researchers discovered that the receptor was activated by chemical cooling agents such as men-thol, a natural product of mint, and cool air. They reported their discovery, or "cloning," of the re-ceptor in "Nature" (March 7, 2002), hypothesizing that the receptor would play a key role in sensing cold. However, some subsequent papers questioned this theory.

In the current study, the team confirmed their hypothesis by "knocking out" the gene that synthesizes the receptor, both in sensory neurons in cell culture and in mice. The cells in culture were unresponsive to cooling agents, including menthol. The genetically engineered mice did not discriminate between warm and cold surfaces until the temperature dropped to extremes.

"It's been known for years that menthol and related cooling agents evoke the psychophysical sensation of cold – somehow by interacting with the aspect of the sensory nervous system that's related to cold detection," says Julius.

The current study, he says -- led by Diana M. Bautista, PhD, and Jan Siemens, PhD, of the Julius lab and Joshua M. Glazer, PhD, of the lab of co-senior author Cheryl Stucky, PhD, of the Medical College of Wisconsin – puts that question to rest.

As the mice lacking the gene were not completely insensitive to cold -- they avoided contact with surfaces below 10 degrees C, though with reduced efficiency -- the next step, says Julius, will be to illuminate this residual aspect of cold sensation.

The finding is the latest of a series of discoveries led by the Julius lab on the molecular mecha-nisms of temperature sensation and pain. In 1997, the lab cloned the gene for the capsaicin re-ceptor, the main pungent ingredient in some chili peppers (Nature, Oct. 23, 1997), and in 2000 reported that, in mice, the receptor triggers the nerves to fire pain signals when they are ex-posed to high ambient heat or the fiery properties of peppery food. (Science, April 14, 2000). The study demonstrated that capsaicin and noxious heat elicit the sensation of burning pain through activation of the same receptor on sensory neurons.

Most recently, they identified the receptor of isothiocyanate compounds, which constitute the pungent ingredients in such plants as wasabi and yellow mustard. In response to high tempera-tures, the receptor produces pain and irritation.

"All of these studies use natural products to understand pain mechanisms in the periphery of the body, where they are first sensed," says Julius.

Ultimately, pain signals are transmitted from the peripheral nervous system into the body's central nervous system – moving through nerves in the spinal cord and brain stem up to the brain, which prompts a response, or "feeling." Co-author of the current study Allan Basbaum, PhD, also of UCSF, is a pioneer of research into the mechanism of chronic pain within the central nervous system.

The Julius team's complementary work is focused at the level of the sensory nerve fiber, where the signals are first initiated. "We want to know," Julius says, "how do you detect these stimuli to begin with" How do your sensory nerve endings do this to begin with" And what are the biochemical and biophysical mechanisms that account for this""

All three receptors the Julius lab has discovered are members of the TRP family of ion chan-nels expressed on sensory neurons. The latest finding adds to the evidence, says Julius, that TRP channels are the principal transducers of thermal stimuli in the mammalian periphery nervous system.

Better Insight into Brain Anatomical StructuresManganese oxide nanoparticles as contrast agents for brain magnetic resonance imaging

Magnetic resonance imaging is a very effective method for revealing anatomical details of soft tissues. Contrast agents can help to make these images even clearer and allow physiological processes to be followed in real time. Conventional gadolinium complexes currently used as MRI contrast agent cannot reveal anatomic structures. As reported in the journal Angewandte Chemie, Korean researchers led by Jung Hee Lee at Samsung Medical Center and Taeghwan Hyeon at Seoul National University have now developed a new MRI contrast agent using man-ganese oxide nanoparticles that produces images of the anatomic structures of mouse brain which are as clear as those obtained by histological examination .

Magnetic resonance images after injection of the manganese oxide nanoparticles gave a view into different areas of the mouse brains—in excellent resolution. “We have developed the first truly biocompatible MRI contrast agent for anatomical brain imaging,” Lee and Hyeon point out. “With this agent, we are able to get high-contrast views of the anatomical details of live mouse brain.” The researchers hope that their new contrast agent will allow better research and diagno-sis of brain diseases involving the CNS (central nervous system), such as Alzheimer’s disease, Parkinson’s disease, strokes, and tumors.

Furthermore, the Korean team was able to attach antibodies to the manganese oxide nanoparticles. These antibodies recognize and specifically bind to receptors on the surface of breast cancer cells. In mouse brains with breast cancer metastases, the tumors were clearly highlighted by the antibody-coupled contrast agent. The same principle should allow other dis-ease-related changes or physiological systems to be visualized by using the appropriate antibod-ies.

Secrets of Sun-like star probedThe first image of the surface of a Sun-like star has been captured.

It confirms that Altair, one of the brightest stars in the night sky, is a rapidly spinning, non-spherical body.

Until now, telescopes have only been powerful enough to zoom in on the Sun or on rare giant stars outside of the Solar System.

But researchers, writing in the journal Science, say they got around this problem by combining the light from four separate telescopes.

Lead researcher John Monnier, an astronomer at the University of Michigan, US, said: "What may not be obvious to most people is that until now we have not really had the zoom-up capabil-ity with our telescopes to make images of stars that are like the Sun."

Altair is a rapidly rotating star and is elongated in shapeCompared with the Sun, which can be imaged in spectacular detail,

and some rare gas giants, stars outside of the Solar System simply appear as specks of light through even the most powerful telescopes.

Professor Monnier said: "Even Altair, which is pretty close at 15 light years away and very bright, would be very challenging to zoom-up on. In order to do this, you would need a telescope that is about 300m (1,000ft) across - and that is a long way beyond our engineer-ing capabilities"Elongated shape

To image Altair, which is the brightest star in the Aquila constella-tion (The Eagle) and clearly visible to the naked eye, the researchers harnessed the power of four telescopes at Georgia State University's Center for High Resolution Angular Astronomy (Chara).

Professor Monnier told the BBC News website: "By combining and processing the light from the four smaller telescopes, using a new instrument called the Michigan Infrared Combiner, we are creating an image as if it is coming from a much bigger tele-scope."

The result was a detailed surface image of Altair.Previous research had suggested that this bright star was spinning

very rapidly - about 60 times faster than our home star. But until now, the effect of the rapid rotations on the its shape was not clear.

Professor Monnier said: "Computer models had given very basic predictions of what happens if you have a star that is spinning very fast, but our image definitely confirmed that this star was elongated in shape."

The centrifugal forces created as the star was spinning were flattening it into an oval shape, he said.

Altair appears as a speck from other telescopesHowever, the image also revealed that the amount of distortion and changes in surface tem-

perature at the equator differed from current models.Professor Monnier said: "Since we have a lot more data and the images are very powerful, we

can do the modelling again to give a new level of detail."We're testing the theories of how stars work in much more detail than ever before."

Basic research must orient itself toward societal goalsLeading science policy analysts urge greater emphasis on community participation

Citing numerous examples historical and contemporary, leading Science Policy Analysts Sheila Jasanhoff (Kennedy School of Government, Harvard) and Suzan Cozzens (Georgia Institute of Technology) have urged a fundamental shift in the way scientific research is carried out.

Speaking at the Science Impact conference, Vienna May 10-11th, Jasanhoff stated that "In or-der to create the linkages between basic science and the world of applications – the area I'm calling the 'Frontier of Dreams', we need networks that are incredibly heterogeneous – not only because they involve science and technology – but they also bringing in things like the law and other institutions."

"You can be pursuing fundamental knowledge, learning fundamental things about nature, but at the same time generally orienting your research towards societal goals. I do not see it as be-ing incompatible," added Cozzens, who lectured on "Maximizing Social Impact through Science and Technology: Best Practices".

Jasanhoff sought to depict the often unclear, ill-defined pathways from basic to applied sci-ence, through a series of examples ranging from the relatively poor-uptake of GM Food crops of

the 1990s to the current overwhelmingly negative public perception surrounding the human genome project and the so-called 'genetic revolution'.

"Biotechnology was framed in the U.S. from the beginning as a collection of new products pro-duced through a means of development that did not by itself require scrutiny," she said. "As a result, in America we never adopted legislation for biotechnology, instead we attempted to regu-late the products that came out of the biotech revolution.

Her argument is that failure at the market level is often the "result of a narrow framing process and in sufficiently inclusive a democratic process".Sustainability of Economic Growth

"The challenge here is that economic growth is a very good thing, of course, but it doesn't ac-tually automatically produce the kind of society that we want to live in. It doesn't produce all of those characteristics," stated Cozzens, whose research has delved into on-the-ground impacts of frontier research over the past 150 years.

Her studies showed, for example, that in the U.S. vast disparities have existed when it comes to dissemination of benefits between rich and poor, among ethnic groups, and between men and women. The issues have been addressed over time, but Cozzens feels interventions at an earlier stage could substantially raise the quality of life.

"Starting with the political rise of women in the U.S. through participation in the political process – as females members of congress and senate were elected they looked at huge NIH [National Institute of Health] budget and said – what's in this budget for us" And discovered there were oddities there – a neglect of women's issues including such things as breast cancer research being done on men."

Cozzens drew on further contemporary examples of such disparity on a worldwide scale, such as the high prices of HIV drugs which made them inaccessible for vast swathes of the developing world, which was at the time "considered a scandal by people within the medical community it-self and within civil society".

One solution, she said, lay in creating a system of advance purchase commitments whereby a donor coalition of countries would come together and buy a drug before it even came to market, thus ensuring a market for the drug company at a reasonable price.

Such "public sector stimulation of private sector activity", as Cozzens puts it, is the way to move forward.

"In order to create a sustainable society public leadership and public funding has a very im-portant role to play maintaining traditional mechanisms of orienting public research to social goals…public agencies also need to think more about working with industry to produce the kinds of societies that we want to live in.

"What's important here is that you do the work in a way that actually shifts power from the current centre out. If you don't change the power relationship, you haven't actually made it sus-tainable."

Limiting stroke damage is focus of studyBrain damage that occurs even days after a stroke, increasing stroke size and devastation, is

the focus of researchers trying to identify new treatments."This would be a death wave coming through; neurons are dying here," says Medical College

of Georgia Neuroscientist Sergei Kirov as he watches moving images of compounding events that kill brain tissue in the stroke's core.

Within seconds of a clot or hemorrhage cutting off blood, oxygen and glucose, the neuron's powerhouses, or mitochondria, shut down and the key energy source ATP goes away. Energy loss shuts down the sodium-potassium pump and the membrane that keeps the right substances inside and outside the cell becomes dysfunctional. Neurons swell and the proper electrical bal-ance – essential for neuronal activity – is lost.

"This is what is happening in the ischemic core; dendrites get beaded, spines are lost and synapses are probably lost at the same time," says Dr. Kirov describing rapidly deteriorating communication points for neurons. "This is not recoverable; everything dies here," he says of the destruction, termed anoxic depolarization.

Damage doesn't stop there. In the minutes, hours and even days following stroke, waves of peri-infarct depolarization pound surrounding brain tissue, where blood flow is reduced by about 60 percent.

"It's enough oxygen and energy for neurons to survive for some time, but not enough to func-tion properly," says Dr. Kirov, who received a $1.4 million, five-year grant from the National Insti-tute of Neurological Disorders and Stroke, to study this compromised tissue around the stroke core called the penumbra. His grant was ranked among the top 1 percent of those reviewed by the study section.

"If the recurring waves continue, finally they will kill cells," says Dr. Kirov who wants to better understand this depolarizing event with the goal of stopping it. "We are trying to block this event to save the penumbra. Part of the recovery is if you can restore the normal electrical activity of neurons. We need some energy to do that."

He's using real-time microscopical imaging to monitor changes in neurons and their dendrites and spines following a stroke, and pharmaceuticals – including an antibiotic and an anesthetic – to try to stop it. Disintegration of a neuron's dendrites and spines, which receive messages from other neurons via synapses, is an early indicator of trouble. Studies are being done in an animal model for stroke and dissected but still-viable brain tissue.

"The penumbra exists for several days, so this is basically a window of opportunity to save this region, but we don't yet have good drugs to do this. We need to target this area for drug treat-ment," Dr. Kirov says.

So Dr. Kirov studies dendrite and spine damage that occurs in anoxic depolarization and peri-infarct depolarization and watches their recovery after a short simulated stroke.

He believes by finding a way to inhibit anoxic depolarization in a slice of living brain, he can protect neurons by stopping structural and functional damage and promoting recovery.

His previous work has shown that cold also inhibits the sodium-potassium pump, resulting in dendrite beading and spine loss, and that warming of brain tissue and pump revival quickly heals old spines and induces new ones.

Now he wants to know if the new spines function and last and if this adaptive recovery also occurs when stroke is the culprit.

Galaxy Cluster Takes It to the ExtremeEvidence for an awesome upheaval in a massive galaxy cluster was discovered in an image

made by NASA's Chandra X-ray Observatory. The origin of a bright arc of ferociously hot gas ex-tending over two million light years requires one of the most energetic events ever de-tected.

The cluster of galaxies is filled with tenuous gas at 170 million degree Celsius that is bound by the mass equivalent of a quadrillion, or 1,000 trillion, suns. The temperature and mass make this cluster a giant among giants.

"The huge feature detected in the cluster, combined with the high temperature, points to an exceptionally dramatic event in the nearby Universe," said Ralph Kraft of the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass., and leader of a team of as-tronomers involved in this research. "While we're not sure what caused it, we've narrowed it down to a couple of exciting possibilities."

The favored explanation for the bright X-ray arc is that two massive galaxy clusters are un-dergoing a collision at about 4 million miles per hour. Shock waves generated by the violent encounter of the clusters' hot gas clouds could produce a sharp change in pressure along the boundary where the collision is occurring, giving rise to the observed arc-shaped structure which resembles a titanic weather front.

Chandra X-ray Image of 3C438Evidence for an awesome upheaval in a massive galaxy cluster was discovered in an im-age made by NASA's Chandra X-ray Observatory. The origin of a bright arc of extremely

hot gas extending over two million light years requires one of the most energetic events ever detected. There are also hints of a cavity in the hot gas to the upper left.

Scale: Image is 8.4 arcmin per side(Credit: NASA/CXC/CfA/R.P.Kraft)

"Although this would be an extreme col- li-sion, one of the most powerful ever seen, we think this may be what is going on," said team member Martin Hardcastle, of the University of Hertfordshire, United Kingdom.Images of 3C438 and Surrounding Galaxy Cluster

A problem with the collision theory is that only one peak in the X-ray emission is seen, whereas two are expected. Longer observations with Chandra and the XMM-Newton X-ray observatories should help de-termine how serious this problem is for the collision hypothesis.

Another possible explanation is that the disturbance was caused by an outburst generated by the infall of matter into a su-permassive black hole located in a central galaxy. The black hole inhales much of the matter but expels some of it outward in a pair of high-speed jets, heating and pushing aside the surrounding gas.

VLA Radio Image of 3C438This radio image from NRAO's Very Large Array shows the inner-most region of 3C438.

Jets seen in the radio data do not point in the same directions as the cavity structure seen in the X-ray, adding more mysteries about this system.

(Credit: Radio: NRAO/VLA/A.H.Bridle & R.G.Strom; X-ray: NASA/CXC/CfA/R.P.Kraft)Such events are known to occur in this cluster. The galaxy 3C438 in the central region of the

cluster is known to be a powerful source of explosive activity, which is presumably due to a cen-tral supermassive black hole. But the energy in these outbursts is not nearly large enough to ex-plain the Chandra data.

"If this event was an outburst from a supermassive black hole, then it's by far the most power-ful one ever seen," said team member Bill Forman, also of CfA.

The phenomenal amount of energy involved implies a very large amount of mass would have been swallowed by the black hole, about 30 billion times the Sun's mass over a period of 200 million years. The authors consider this rate of black hole growth implausible.

"These values have never been seen before and, truthfully, are hard to believe," said Kraft.These results were presented at the American Astronomical Society meeting in Honolulu, HI,

and will appear in an upcoming issue of The Astrophysical Journal. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the agency's Science Mission Direc-torate. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass.Additional information and images are available at: http://chandra.harvard.edu and http://chandra.nasa.gov

Russia bans human tissue export in bioweapon alert* 16:22 30 May 2007

* NewScientist.com news service* New Scientist and AFP

Russia has banned the shipment of medical specimens abroad, threatening hundreds of pa-tients and complicating drug trials by major companies, the national Kommersant newspaper re-ported on Wednesday.

Kommersant attributed the ban to fears in the secret service that Russian genetic material could be used abroad to make biochemical weapons targeting Russians. The quality daily cited anonymous sources in the medical community.

The ban, initiated by the Ministry of Health and carried out by the Federal Customs Service, began on 28 May. Shipment beyond Russia's borders of all biological material, including hair and blood, has been blocked.

"If this is true, it will hit us like a cannonball" due to the centre's reliance on processing of medical specimens abroad, Aleksei Maschan, director of the Central Children's Hospital, Moscow, told the newspaper.Secret service warning

The ban may also complicate clinical trials by major pharmaceutical companies, including GlaxoSmithKline, which runs trials on tens of thousands of Russians.

The Russian Customs Service and Ministry of Health refused to comment on the reports.An anonymous medical source linked the ban to a report by the FSB secret service in May

2007, that he said warned of Russian genetic material being used in Western clinics to prepare biological weapons that would harm only Russians.

Nikolai Yankovsky, head of the Russian Institute of Sciences' General Genetics Institute, ridiculed the idea of a ban on transporting genetic material abroad. "Forbidding the shipment of one's DNA abroad is impossible – I am my DNA," he told Echo of Moscow radio.

Okay, I give up! Let’s give George bush a doctorate. He’s obviously the smarter president.

Life decisions separate 'hawk' from 'dove'* 30 May 2007

* NewScientist.com news service* Rowan Hooper

ASK anyone who has regular contact with animals - from farmers to pet owners - and they will tell you that animals have personalities. Some are docile, some are tetchy. Animals are individu-als, with a range of temperaments, from aggressive to shy. Explaining the evolution of personal-ity has been difficult. Now it seems the decisions animals make about how to live their lives and when to reproduce may be what gives them their personalities.

To test the idea, Max Wolf of the theoretical biology group at the University of Groningen, the Netherlands, and colleagues built an evolutionary model based on trade-offs animals face during their lives. For example, young oystercatchers have to decide whether to move into a vacant ter-ritory with a poor food supply and start breeding, or wait for higher quality territory to become available. "We predict that the ones that delay reproduction will be more risk-averse, and more shy and non-aggressive, than the ones that start reproducing immediately," says Wolf. This ex-ample is in birds, but all animals face similar decisions.

The model incorporates this dilemma over current or future reproduction, and looks at how behavioural traits evolve over many generations. Individuals in the model are confronted with a risky situation in which they might get injured but where there is also a chance of a high pay-off. This is similar to the famous "hawk-dove" game in which an individual who behaves aggressively has a higher chance of winning a fight over a resource than one who behaves meekly. Hawks, however, are more likely than doves to die in the attempt.

The team also examined how animals forage when there are predators around. Bolder individ-uals get more food because they don't waste time hiding - but they also run the risk of being eaten. In other words, individuals that live fast do risk dying young.

In the model, individuals can differ in their aggressiveness, boldness and intensity of ex-ploratory behaviour. These behaviour traits are linked to the probability of obtaining resources and successfully reproducing (Nature, vol 447, p 581).

"We find that evolution results in personalities," says Wolf. "Individuals that have more to lose evolve to be more risk-averse in the different risk situations." Individuals that put more emphasis on future reproduction evolve to have low levels of aggression and behave shyly. In contrast, in-dividuals that invest more in current reproduction evolve to be more aggressive risk-takers.

It is the first time that a formal mathematical model has been produced incorporating these different parameters to explain why individual animals have different personalities. The model also explains consistency in behaviour, says Wolf.

Judy Stamps of the University of California, Davis, has also suggested there is a link between life-history trade-offs and personality (Ecology Letters, vol 10, p 355). But she points out that the first set of models produce bimodal personalities: animals that are either bold or shy, but never in between. In real life, animals are not just one thing or the other. Wolf and colleagues address this in another model by invoking “genetic constraints”, says Stamps, arguing that many genes with small effects govern the development and expression of personality traits.

"I have trouble accepting this result because there is plenty of evidence that genetic systems can produce highly bimodal behavioural trait distributions, when those distributions are adap-tive,” says Stamps. "The authors may need to think a bit more about the processes that gener-ate continuous trait distributions."

Our upright walking started in the trees* 18:28 31 May 2007

* NewScientist.com news service

* Rowan HooperOur ancient tree-dwelling ancestors stood upright on

two legs – a trait modern humans have retained, while other great apes have evolved four-legged knuckle-walk-ing, researchers say.

It was one of the characteristics that was supposed to define the ancestral human line from our great ape cousins: We walk upright, while chimps and gorillas walk on four legs, using their knuckles.

Now it seems that we did not evolve from knuckle-walkers – bipedalism apparently arose far earlier in evo- lu-tionary history, when our ancestors were still in the trees.An adult female Sumatran orang-utan and her infant in the Gunung Leuser National Park,

Indonesia. [Image courtesy of SKS Thorpe]Several scenarios have been proposed to explain why we came to walk on two legs, from the

idea that it allowed our ancestors to feed more efficiently and carry infants, to the idea that the posture reduced our exposure to sunlight and so gave us longer to forage. Canopy skills

Susannah Thorpe, of the University of Birmingham, UK, and colleagues have made extensive observations of the most arboreal of the modern great apes, the orang-utan, and come to an-other conclusion, that bipedalism evolved to help us move about the forest canopy.

"The orang-utan is the only great ape still living in its ancestral habitat," says Thorpe, making them good models for understanding the selection pressures on ancestral apes.

Thorpe spent a year recording orang-utan behaviour in the Gunung Leuser National Park in Sumatra, Indonesia, and from nearly 3000 observations of locomotion, the team concluded that the apes were more likely to walk on two legs - using their hands to guide them - when they are on the thinnest branches, less than 4 centimetres in diameter.

On medium-sized branches - those greater than 4 cm but less than 20 cm diameter - the apes tended to walk bipedally, but used their arms to support their weight by swinging or hanging.

Only on the largest branches, with a diameter greater than 20 cm, did the animals walk on all fours.Fruits of bipedalism

Since orang-utans are fruit eaters, and fruit is more likely to be found on the ends of thinner branches, the ability to walk out along them is advantageous. Since they also spend most of their time in the trees, the ability to move over thinner branches helps when it comes to crossing from tree to tree and traversing the canopy, says Thorpe.

When walking bipedally, orang-utans extended their legs at the knee and hip to give them a straighter posture, in contrast to what happens when chimps try to walk on two legs. Chimps are forced to waddle with bent knees and their torso bent over at the hip. When humans run on springy surfaces they also keep their legs straight, like orang-utans, Thorpe points out.

"Walking upright and balancing themselves by holding branches with their hands is an effec-tive way of moving on smaller branches," says Robin Crompton of the University of Liverpool, UK, who was also involved in the study.

"It helps to explain how early human ancestors learnt to walk upright while living in the trees, and how they would have used this way of moving when they left the trees for a life on the ground."Ground foragers

So, rather than evolving to walk on two feet after scrabbling around on the floor on all fours, the theory suggests our ancestors already had the rudimentary means of walking on two feet be-fore they even left the trees.

When the ancestors of chimps and gorillas left the trees, however, they needed to maintain the ability to climb tree trunks. This need for tree-climbing strength and anatomy guided their evolution at the ex-pense of more efficient terrestrial movement, and there-fore led to knuckle-walking, says Crompton.

Orang-utans are the most distant of our relatives among the great apes, followed by gorillas, and then bonobos and chimpanzees. The ancestors of the latter two

species split from the human line around 6 million years ago; the orang-utan ancestor split from the human ancestor around 10 million years ago.

Thorpe and colleagues suggest that at sometime in the Miocene epoch - 24 to 5 million years ago - the increased gaps in the forest canopy that came about as a result of climate fluctuations had a profound effect on our ape ancestors.

Some of them - the ancestors of chimps and gorillas - specialised on climbing high into the canopy and crossing the gaps between trees by knuckle walking. Others - the ancestors of hu-mans - retained their ability to walk on two legs, and specialised on collecting food from smaller trees and the ground.

An adult female Sumatran orang-utan doing the splits in the Gunung Leuser National Park, Indonesia. [Image courtesy of SKS Thorpe]

Plausible mechanismThe idea of an arboreal origin for human bipedalism has been proposed before, says Chris

Stringer, a palaeontologist at the Natural History Museum, London. "Nevertheless, this is the best observational data on the importance of hand-assisted bipedalism to orangs, and its possi-ble implications for the evolution of human bipedalism."

Since all the sites which have yielded fossil evidence of our earliest ancestors were forested or wooded, rather than open, Stringer says, "arboreal bipedalism is certainly a very plausible mech-anism for the origins of walking upright."

Paul O’Higgins, of the Functional Morphology and Evolution unit at the University of York, UK, says the finding makes it more difficult to find a feature unique to the human ancestral line. "If extended hip and knee bipedalism did indeed arise in the distant past, this makes the task of identifying possible ancestors of the human line much more difficult," he says.

There has been tantalising fossil evidence suggesting an early origin for bipedalism, says Crompton. "And the orang-utan is the only ape with a knee joint similar to that of humans."

Despite this, the idea that all apes at one stage had the potential to walk on two legs and that from this starting point some evolved to knuckle walk and some evolved bipedalism has been re-sisted. "Perhaps we’ve been too focused on the African apes," says Thorpe. "The trend has been to look at them to explain human evolution." Journal reference: Science (DOI: 10.1126/science.1140799)

Smart painkillers target damaged tissue* 31 May 2007

* NewScientist.com news service* Roxanne Khamsi

Imagine a painkiller that only switches on in injured tissue, leaving the rest of the body unaf-fected. That is the idea behind a new class of pH-dependent drugs that interfere with nerve sig-nals to the brain and spinal cord - but only where the tissue is slightly acidic due to injury.

Normal tissue has a pH of around 7.4, but this drops to around 7.0 in injured tissue, largely be-cause the blood supply is disrupted, resulting in the accumulation of waste products such as car-bon dioxide and a switch to anaerobic respiration, which produces lactic acid.

The new drugs act by blocking NMDA receptors, which are found on cells throughout the brain and central nervous system and are implicated in a variety of nerve functions, including pain sensitisation. Earlier generations of drugs, such as ketamine, also targeted NMDA receptors, but these often have unwanted side effects such as impaired movement or hallucinations, because they act on undamaged nerve tissue as well.

Ray Dingledine of the Emory University School of Medicine in Atlanta, Georgia, and his col-leagues have now developed a compound called NP-A, that binds to the base of NMDA receptors and stops glutamate and a related neurotransmitter called NMDA from binding. A slight drop in pH can cause a significant boost in NP-A's ability to block the receptor - for example, a drop in pH from 7.6 to 6.9 causes the compound's activity to increase 62 fold.

This means that NP-A gets switched on only where it's most needed, says Dingledine, who has now set up a company called NeurOp to develop the drug further. "It's a context-dependent blocking of pain, which is a new strategy for these receptors," he says.

He showed that rats were significantly less sensitive to pain in an injured paw when they were injected with NP-A. Usually, rats will flinch when their paw is touched using a force greater than 15 grams. When they have injured paws, however, they pull their leg back when the force is only 2 g. Forty-five minutes after an NP-A injection, the rats did not move their injured paws away un-til the force was about 12 g.

The pain stayed away for about 3 hours, and the animals showed no signs of side effects. The results were presented at the annual meeting of the Biotechnology Industry Organization in Bos-ton, Massachusetts, last month.

Dingledine believes that a compound like NP-A could one day provide pain relief for people with agonising peripheral nerve damage, or neuropathy. Doctors often prescribe drugs such as gabapentin, which boost a pathway in the brain that inhibits pain through a neurotransmitter called GABA. However, these drugs don't work for everyone - possibly because GABA misfiring is not necessarily the cause of the pain.

Min Zhuo of the University of Toronto in Canada, who studies NMDA receptors and pain, says that a drug targeting NMDA receptors might help a different subset of patients who experience pain because of NMDA overactivation. "GABA inhibition and NMDA firing are like yin and yang," he says.

Transformation for people with AIDS on the horizonDrug resistant HIV: Promising research on three new drugs gives hope for chronically in-

fected patientsA major breakthrough for people with AIDS is on the horizon, according to an editorial in this

week’s BMJ.Three new drugs are predicted to help transform the long-term prognosis for people with the

AIDS virus, says an editorial in the journal, which points towards highly promising results from trials of three new drugs.

HIV patients in “deep salvage” – meaning those people who have developed multidrug resis-tant HIV that does not respond to drug combination therapy – could benefit the most.

“This year, we may witness a dramatic shift in how these patients are managed,” says the edi-torial written by Hiroyu Hatano, infectious diseases fellow and Steven Deeks, associate professor of medicine, both of San Francisco General Hospital, University of California, USA.

For the first time in the HIV epidemic, three new agents have been developed for the manage-ment of the drug resistant virus, they say.

“Hence for patients in deep salvage, 2007 may be comparable to the landmark events of 1996, when the near miraculous effects of combination therapy were first observed,” they write.

The drugs are the HIV integrase inhibitors, R5 inhibitors, and etravirine (TMC125) – a second generation non-nucleoside reverse transcriptase inhibitor.

Some caution is necessary about potential hype around new treatments for these patients, they warn, and add that it is not possible to predict the end of deep salvage for all people with HIV.

But within the next year, the world will “probably” see a remarkable transformation in the long-term prognosis for a generation of chronically ill adults with HIV they conclude.

More rib fractures, but better survival ratesJournal study tests trained and untrained adults in cardiopulmonary resuscitation

New findings show that the majority of people untrained in how to perform cardiopulmonary resuscitation, and even many trained emergency personnel, do not push with enough force to properly administer CPR.

The research tested 104 adults untrained in CPR and 83 firefighters, trained in the procedure. The findings, to be published in the June issue of the journal Cardiovascular Engineering¹, showed that most of the untrained people simply do not apply enough force, said Leslie Geddes of Purdue University, one of the authors of the study.

The success rate for CPR ranges from 5 percent to 10 percent, depending on how quickly it is administered after a person's heart stops. "This is important because every minute lost in apply-ing CPR results in a 10 percent decrease in successful resuscitation," Geddes said. "Time is the enemy. After 10 minutes, very few are resuscitated. The American Heart Association recom-mends pushing with enough force to compress the chest 1.5 to 2 inches, which requires 100 to 125 pounds of force.”

The research represents the first time such measurements have been recorded to quantify just how hard people push in a simulated CPR test. The findings showed that 60 percent of the CPR-trained rescue personnel pushed with more than 125 pounds, whereas more than 60 per-cent of those not trained in CPR failed to push with more than 125 pounds of force.

The people in the study were asked to push on a bathroom scale as though they were per-forming CPR, and their force was recorded by the scale. "All we are trying to establish is how hard people are able to push in a simulated CPR situation," Geddes said. "You can't tell from the data how successful they would have been at resuscitation in a real-life situation."

Pushing with more than 125 pounds increases the potential for rib fractures. Neverthe-less, the chances of survival increase enormously. New guidelines from the American Hearth Association recommend that rescuers performing CPR should "push harder and faster," Geddes said. "As a result of this recommendation, it's likely that the resuscitation rate will increase, but it's equally likely that the fracture rate will increase."

1. Geddes A. et al. (2007). Chest Compression Force of Trained and Untrained CPR Rescuers (Cardio-vascular Engineering, DOI 10.1007/s10558-007-9029-5).

Research finds that Earth's climate is approaching 'dangerous' pointNASA and Columbia University Earth Institute research finds that human-made greenhouse

gases have brought the Earth’s climate close to critical tipping points, with potentially dangerous consequences for the planet.

From a combination of climate models, satellite data, and paleoclimate records the scientists conclude that the West Antarctic ice sheet, Arctic ice cover, and regions providing fresh water sources and species habitat are under threat from continued global warming. The research ap-pears in the current issue of Atmospheric Chemistry and Physics.

Tipping points can occur during climate change when the climate reaches a state such that strong amplifying feedbacks are activated by only moderate additional warming. This study finds that global warming of 0.6ºC in the past 30 years has been driven mainly by increasing green-house gases, and only moderate additional climate forcing is likely to set in motion disintegra-tion of the West Antarctic ice sheet and Arctic sea ice. Amplifying feedbacks include increased absorption of sunlight as melting exposes darker surfaces and speedup of iceberg discharge as the warming ocean melts ice shelves that otherwise inhibit ice flow.

The researchers used data on earlier warm periods in Earth’s history to estimate climate im-pacts as a function of global temperature, climate models to simulate global warming, and satel-lite data to verify ongoing changes. Lead author James Hansen, NASA Goddard Institute for Space Studies, New York, concludes: “If global emissions of carbon dioxide continue to rise at the rate of the past decade, this research shows that there will be disastrous effects, including increasingly rapid sea level rise, increased frequency of droughts and floods, and increased stress on wildlife and plants due to rapidly shifting climate zones.”

The researchers also investigate what would be needed to avert large climate change, thus helping define practical implications of the United Nations Framework Convention on Climate Change. That treaty, signed in 1992 by the United States and almost all nations of the world, has the goal to stabilize atmospheric greenhouse gases “at a level that prevents dangerous human-made interference with the climate system.”

Based on climate model studies and the history of the Earth the authors conclude that addi-tional global warming of about 1ºC (1.8ºF) or more, above global temperature in 2000, is likely to be dangerous. In turn, the temperature limit has implications for atmospheric carbon dioxide (CO2), which has already increased from the pre-industrial level of 280 parts per million (ppm) to 383 ppm today and is rising by about 2 ppm per year. According to study co-author Makiko Sato of Columbia’s Earth Institute, “the temperature limit implies that CO2 exceeding 450 ppm is al-most surely dangerous, and the ceiling may be even lower.”

The study also shows that the reduction of non-carbon dioxide forcings such as methane and black soot can offset some CO2 increase, but only to a limited extent. Hansen notes that “we probably need a full court press on both CO2 emission rates and non-CO2 forcings, to avoid tip-ping points and save Arctic sea ice and the West Antarctic ice sheet.”

A computer model developed by the Goddard Institute was used to simulate climate from 1880 through today. The model included a more comprehensive set of natural and human-made climate forcings than previous studies, including changes in solar radiation, volcanic particles, human-made greenhouse gases, fine particles such as soot, the effect of the particles on clouds and land use. Extensive evaluation of the model’s ability to simulate climate change is contained in a companion paper to be published in Climate Dynamics.

The authors use the model for climate simulations of the 21st century using both ‘business-as-usual’ growth of greenhouse gas emissions and an ‘alternative scenario’ in which emissions de-crease slowly in the next few decades and then rapidly to achieve stabilization of atmospheric CO2 amount by the end of the century. Climate changes are so large with ‘business-as-usual’, with additional global warming of 2-3ºC (3.6-5.4ºF) that Hansen concludes “‘business-as-usual’ would be a guarantee of global and regional disasters.”

However, the study finds much less severe climate change – one-quarter to one-third that of the "business-as-usual" scenario – when greenhouse gas emissions follow the alternative sce-nario. “Climate effects may still be substantial in the 'alternative scenario’, but there is a better chance to adapt to the changes and find other ways to further reduce the climate change,” said Sato.

While the researchers say it is still possible to achieve the “alternative scenario,” they note that significant actions will be required to do so. Emissions must begin to slow soon. “With an-other decade of ‘business-as-usual’ it becomes impractical to achieve the ‘alternative scenario’ because of the energy infrastructure that would be in place” says Hansen.

----------------------http://www.nasa.gov/vision/earth/environment/danger_point.html

Boost to artery block treatmentScientists are working on ways to cut the risk of blood clots following treatment to unblock

clogged arteries.Stents, which are tiny tubes used to hold open the diseased blood vessels of heart patients,

can themselves become blocked following treatment.A team from Germany reports success in The Lancet with a new biodegradable prototype. And

an Irish team is to begin testing a new coating for stents.Experts welcomed the findings but said more work was needed.

Treating clogged arteriesTo improve blood flow through clogged heart blood vessels, a balloon is inflated inside the

artery.This treatment - angioplasty - improves the blood supply to the heart muscle, which helps pre-

vent angina and heart attacks.Once the balloon is withdrawn stents are inserted to prevent the artery from re-narrowing.

The need for stenting is only temporary, but current metal stents remain in place for life.There is a risk that blood clots can occur within the stent and re-block the artery.Such events are rare, but can be life threatening.

New developmentsThe stents tested by an international team led by Professor

Raimund Erbel of the West German Heart Centre Essen, are made from biodegradable magnesium.

Within four months of fitting they can dissolve and completely dis-appear, which the scientists reason will eliminate the risk of stent re-blockage.

In tests, the biodegradable stents worked as well as conventional metal stents over 12 months, The Lancet reports.

The coronary arteries supply the heart muscle with bloodThey were also safe - none of the 63 patients had heart attacks or developed a clot where the

stent had been.Almost half of the patients had new blockages elsewhere in their arteries which would need

treatment.This research shows that absorbable stents can be used as a safe alternative in the future

Professor Peter WeissbergBut this is expected in heart patients because of the poor general state of their arteries and is

unrelated to the type of stent used.Meanwhile, Professor Jim McLaughlin and colleagues in Ulster have developed a 3D plasma

coating technique for stents, and are now preparing to test it in clinical trials.The stents, only a few millimetres wide, are covered in a diamond-like carbon structure.This forms a coating which is theoretically smooth enough to repel the proteins which could

form clots.Professor McLaughlin said some forms of carbon were already well-known implant materials

used for heart valves.He said: "Our group are now seeking to further develop and even commercialise the 3-D

plasma-coating technique, which has already shown to be highly biocompatible and promising with regards to its mechanical properties."

Professor Peter Weissberg, medical director at the British Heart Foundation, said: "This re-search shows that absorbable stents can be used as a safe alternative in the future, allowing the blood vessel to repair itself before the scaffold dissolves.

"But before they can be used in routine practise, further research is needed to refine the stents to get the best result."

Coca-Cola and PepsiCo Agree to Curb Animal TestsBy BRENDA GOODMAN

ATLANTA, May 30 — Under pressure from animal rights advocates, two soft drink giants, Coca-Cola and PepsiCo, have agreed to stop directly financing research that uses animals to test or de-velop their products, except where such testing is required by law.

Researchers at People for the Ethical Treatment of Animals sought the assurances after dis-covering studies financed by the companies that used animals like rats and chimpanzees to test taste perception and, in some cases, to bolster support for promotional health claims.

PepsiCo said that it would stop directly financing animal experiments, including some it had fi-nanced through grants given to graduate students through its Gatorade Sports Science Institute.

Elaine Palmer, a spokeswoman for PepsiCo, said that while the company had never supported the idea of animal testing, “We had not been policing it, so that part is new.”

Coca-Cola and PepsiCo are the largest largest manufacturers to agree to the ban.Coca-Cola also said that it would discontinue a grant given to a researcher at Virginia Com-

monwealth University who has been studying taste perception in rats, which share certain taste pathways with humans.

Representatives of Coca-Cola and the university declined to say how much financing the com-pany was providing or to elaborate on what the ultimate application of the research might be.

A research associate at PETA, Shalin G. Gala, said, “We see these statements from Coke and Pepsi, massive global conglomerates, as the beginning of the end of all animal tests on food.”

Scientists conducting basic research in animal models have cautioned against PETA’s hard line, saying their work, which may have medical benefits, would not be possible in many cases without help from corporate sponsors.

“It’s very easy to characterize scientific research like this in a bad light,” said Dr. John A. DeSi-mone, a professor at Virginia Commonwealth University who had been working under the Coca-Cola grant. “To do medical research, you sometimes need an animal model.”

Not everyone agrees with Dr. DeSimone’s thinking, particularly when it involves tests on highly intelligent animals, as did a study involving a Coca-Cola scientist, financed by Nutrasweet, that cut open the faces of chimpanzees to study nerve impulses used in the perception of sweet tastes.

“I have never found chimpanzee work justifiable,” said Dr. Alan Goldberg, director of the Cen-ter for Alternatives to Animal Testing at Johns Hopkins University.

Dr. Goldberg said that over the last 30 years, advances in alternatives to animal models, many of which are usually more scientifically precise, have already reduced the number of lab animals in use by 50 percent.

“The bottom line for me is that I’d love to see animal studies disappear entirely,” Dr. Goldberg said. “In vitro models are cleaner.”

The two soft drink giants are the latest companies to respond to scrutiny by PETA, which has mounted a campaign to denounce animal testing practices in the beverage industry, an industry that, unlike cosmetics or pharmaceuticals, had largely been unpublicized in the animal testing arena.

In January, Roll International, the company that makes Pom Wonderful pomegranate juice, agreed to cease tests on animals after PETA disclosed a 2005 study financed by the company that tested the juice to see if it might relieve artificially induced erectile dysfunction in rabbits.

Hot TopicOutlaw DNA

By GRETCHEN REYNOLDSIt was a single line from a longer e-mail message. But when read

into the record by prosecutors at the drug trial last year of the Ger-man track coach Thomas Springstein, it caused a sensation. “The new Repoxygen is hard to get,” Springstein had written. “Please give me new instructions soon so that I can order the product before Christmas.”

Until that day in the courtroom, Repoxygen was an obscure gene-therapy drug developed at a pharmaceutical lab in Oxford, England, to fight anemia. The lab shelved the product when it seemed unlikely to be profitable. Once it was mentioned in court in January 2006, however, Repoxygen vaulted to celebrity-drug status in Europe. Newspapers and Web sites ran dozens of stories about the imminent danger of the therapy. “The moment that e-mail was presented in open court,” a columnist wrote in the weekend paper Scotland on Sunday, was when the “era of genetic doping . . . arrived.”

Anne-Kathrin Elbe's former coach tried to order bootleg gene therapy.Repoxygen works by worming a specialized gene into its host’s DNA. In the right circum-

stances, the gene directs cells to start making extra erythropoietin (EPO), a hormone that drives the production of red blood cells. More red blood cells means more oxygen transported to mus-cles, which is why athletes have been known to inject themselves with synthetic EPO. By insinu-ating itself into an athlete’s genetic code, Repoxygen would theoretically produce a natural stream of the stuff.

That presumably was its allure for Thomas Springstein, who in all likelihood had heard the ru-mors that a single dose of Repoxygen was not only undetectable but also had the capacity to al-ter an athlete’s DNA. Once a coach for several top German track-and-field athletes, Springstein was tried last year for giving performance-enhancing drugs to unwitting young runners, including one of Germany’s best female hurdlers, Anne-Kathrin Elbe, who was 16 at the time.

“I was taken aback and speechless,” Elbe told me in an e-mail message. “He said that they were vitamins.”

It’s unlikely that Springstein ever got hold of Repoxygen; none was found during a 2004 raid of his home. It’s even harder to say that the “era of genetic doping” is unequivocally upon us. What is clear, and what the Springstein case reminds us, is just how impatient some coaches and athletes are to find new and ingenious ways to cheat. First it was steroids, then EPO, then human growth hormone — and now the illicit grail seems to be gene therapy. Researchers have been hounded with requests for gene therapy from sports teams as well as individual athletes; many scientists also believe that would-be dopers troll the Internet, searching for just the right gene-therapy study to try to duplicate on their own. The formula for Repoxygen itself is publicly accessible, and a few Web sites even claim to have it for sale.

“We filed a patent,” says Alan Kingsman, the chief executive of Oxford BioMedica, the lab that developed Repoxygen. “We published our data. It’s all available to anyone who has the training to understand it.”

So far, there have been no confirmed cases of gene doping in the United States or anywhere else, though that could change during the 2008 Summer Olympics in Beijing, which is when some speculate that gene doping will make its debut. The World Anti-Doping Agency (WADA), which preemptively banned gene doping in 2003, has been funding research at laboratories around the world to develop a reliable blood or urine test to use at the Games. “They’ll freeze samples,” says Theodore Friedmann, a geneticist at the University of California, San Diego, who also is head of a gene-doping advisory panel for WADA. “If gene doping is happening in Beijing, I believe we will be able to tell — if not during the competition, then later.”

Friedmann can’t say just how close WADA is to producing its gene-doping test, and won’t speculate about how foolproof it would be. At present, gene doping is detectable only through biopsies of affected muscle tissue. Cheaters can only hope this remains the case indefinitely.

“We all know people who’ll take anything — anything — to make the Olympic team,” says Darren De Reuck, a running coach in Boulder, Colo., whose athletes include his wife, Colleen, the 2004 United States Women’s Olympic Trials marathon champion. “It doesn’t matter how weird and wacky it sounds. Playing around with genes is about as out-there as anything I’ve ever heard of. So I’m sure some people will think it would be a great thing to try.”

In the United States, the first news media reports of gene doping appeared in the late 1990s, when word got out that “Schwarzenegger mice” were being produced in the lab of H. Lee Sweeney, a molecular physiologist at the University of Pennsylvania. Sweeney, who had been searching for treatments for muscle-wasting diseases, focused his research on a gene that pro-duces a protein called IGF-1, which helps regulate growth. His experiments worked. The mice that had been injected with an extra copy of the IGF-1 gene packed on muscle and became as much as 30 percent stronger than before.

After his work was publicized, Sweeney was inundated with calls from athletes volunteering themselves as human test subjects. One high-school football coach offered up his entire team. “I was quite surprised, I must admit,” Sweeney says. “People would try to entice me, saying things like, ‘It’ll help advance your research.’ Some offered to pay me.”

To this day, Sweeney receives overtures from would-be guinea pigs. “Every time there’s a story about our research or any research similar to ours, we get more calls,” he says. Patiently he’ll explain to the caller that, even when his therapy is ready for human testing — Sweeney says it will be years — there will be risks of infection, rejection, organ failure, possibly death. The callers will listen, he says, and then reply, “O.K., when can we start?”

Other gene-therapy advances are closer to fruition. At Harvard Medical School, Chris Evans, a professor of orthopedic surgery, has located a gene that may treat and prevent osteoarthritis; he and his colleagues have tested it successfully in lame horses and plan to switch to human sub-jects later this year.

“I’ve had lots of people volunteer,” he says. “Some of them are my friends, middle-aged weekend athletes whose knees are shot.” But he’s anticipating that he’ll eventually get requests from coaches and trainers as well. When I ask how his therapy could affect healthy young ath-letes, he replies: “It is possible they could create stronger joints. They could train harder without risking joint injury. But that’s not the point of our research. We’re trying to treat disease.”

The search for effective gene therapies was a primary motivation behind the Human Genome Project, which, between 1990 and 2003, identified the 20,000-plus genes that make up human DNA. Each of these genes expresses a protein that, in turn, regulates cellular functions. If, for in-stance, you have a defective gene for producing the muscle protein dystrophin, your muscles won’t repair themselves correctly. That’s the cause of muscular dystrophy. By fixing glitches in a person’s genome, gene therapy would, in theory, cure any number of devastating genetic dis-eases.

The science is quite simple: typically, the requisite gene is introduced into a virus that is then injected into a patient. The virus can enter the nuclei of host cells, changing their DNA. When the cells replicate, they pass on the new DNA as well.

But the results have been largely disappointing. Hundreds of gene-therapy trials have been performed on humans and animals over the past two decades. A handful of therapies have shown moderate success, but most have done absolutely nothing, good or bad. Some have had unintended, even disastrous consequences. In one 1998 study, baboons were injected with a ge-netic compound similar to Repoxygen designed to alter EPO production. The new gene did, in-deed, produce extra EPO — at an unchecked pace. The baboons’ circulatory systems became so clogged with red blood cells that the animals had to be drained of excess blood. In another study, healthy primates had an unexpected immune reaction to the virus used to carry the EPO gene. Their bodies lost the ability to produce red blood cells. Stricken with anemia, several of the animals had to be euthanized.

Repoxygen is not so capricious. Unlike most experimental EPO gene therapies, Repoxygen has a built-in gauge that recognizes when red-blood-cell counts have fallen below a healthy level. Only then will the gene crank up EPO production. Once normal red-blood-cell counts have been reached, the gene turns itself off. Since athletes presumably have optimum red-blood-cell levels, Repoxygen would likely do nothing for them, except possibly set off an immune reaction to the virus.

Nonetheless, dopers want it, as is apparent by underground Web sites that advertise gene therapies for sale. In the interest of research, Olivier Rabin, the science director of WADA, or-dered some samples. “What came was just versions of synthetic EPO,” he says, not gene-ther-apy drugs. But fraudulent advertising doesn’t seem to be a deterrent to sales.

The Web sites are, Rabin believes, quite popular: “No one ever said the people willing to use gene doping will be great minds or careful scientists.”

The unsettling dystopian aura surrounding gene doping also obscures the fact that this isn’t fantasy science: gene doping is not eugenics. It can’t create superathletes. None of the sub-stances with which dopers will likely experiment would completely rewrite a person’s DNA; nor could dopers pass on their altered genes to future generations. And genetic changes wouldn’t necessarily be permanent.

If successful, gene therapy would affect performance by fractions of seconds. But, of course, gold medals and multimillion-dollar sponsorship deals rest on such knife-edged differences, so the dopers are sure to keep trying.

As for Thomas Springstein, he received a 16-month suspended sentence for supplying an ille-gal substance to a minor. He has been banned from the German Track and Field Federation but is otherwise free to coach. The word is, he’s been getting offers.

Ancient melon found in Shiga Pref.The Yomiuri Shimbun

The inner fruit of what experts believe is the world's oldest melon, dating back about 2,100 years, has been excavated from the Shimonogo ruins in Moriyama, Shiga Prefecture, the Shi-monogo Municipal Board of Education announced Thursday.

The fruit, measuring 10.5 centimeters, was discovered about one meter underground in the Shimonogo settlement, which was surrounded by moats during the Yayoi period (ca 300 B.C.-ca A.D. 300).

The surface of the melon is discolored dark brown. Buried in moisture-rich soil that acted as a vacuum seal, the melon segment was kept from contact with the atmosphere and was able to preserve its inner fruit.

The Research Institute for Humanity and Nature in Kyoto identified the age of the fruit based on radiocarbon dating.

The melon, native to Africa, came to Japan via the Middle East and India. The oldest melon fruit previously discovered was one in China that dated back to the fourth century.

Pregnant mom's exposure to flu vaccine kick-starts fetal immune systemSome researchers have hypothesized that the fetus can be exposed to and mount an immune

response against allergens to which the mother has been exposed, and this may have an effect

on the development of allergic sensitivity (e.g. eczema and asthma) later in an infant’s life. How-ever this hypothesis has remained controversial because of an inability to detect antigen-specific T cells in cord blood. Recently, a newly developed technique known as MHC tetramer staining has facilitated the detection of antigen-specific T cells.

In the June 1 issue of the Journal of Clinical Investigation, a team of researchers led by Rachel Miller from Columbia University used this technique to study cord blood B and T cell immune re-sponses following maternal vaccination against influenza with Fluzone during pregnancy. The vaccination of pregnant women against influenza is considered safe and is recommended by the Centers for Disease Control and Prevention. The authors detected anti-Fluzone antibodies in ap-proximately 40% of cord blood specimens examined. These results and further data reported in the study establish that B and T cell responses to antigens occur in utero following maternal vac-cination against influenza, supporting the theory that the human neonatal immune system is not deficient or incompetent but, rather, capable of responding to environmental exposures. These conclusions have important implications for determining when immune responses to environ-mental exposures begin.

Nursing Home Placement Associated with Accelerated Cognitive Decline in Alzheimer’s Disease

Study by Rush Alzheimer’s Disease Center finds adult day care may help the transition(CHICAGO) – People with Alzheimer’s disease experience an acceleration in the rate of cognitive decline after being placed in a nursing home according to a new study by the Rush Alzheimer’s Disease Center. The study, published in the June issue of the American Journal of Psychiatry, finds that prior experience in adult day care may lessen this association.

The observational study involved 432 older persons with Alzheimer’s disease who were re-cruited from health care settings in the Chicago area. At baseline, they lived in the community and 196 participants were using day care services from 2 to 6 days a week for an overall mean of 1.7 days a week. At six month intervals for up to four years, they completed nine cognitive tests from which a composite measure of global cognition was derived.

On average, cognition declined at a gradually increasing rate for all participants. During the study period, 155 persons were placed in a nursing home, and placement was associated with a lower level of cognition and more rapid cognitive decline.

Study participants who had previous adult day care experience fared better. As level of day care use at study onset increased, the association of nursing home placement with accelerated cognitive decline substantially decreased. Thus, people using day care 3 to 4 days a week at the beginning of the study showed no increase in cognitive decline upon nursing home placement.

“The findings suggest that experience in day care may help individuals with Alzheimer’s dis-ease make the transition from the community to institutional residence,” said study author Robert S. Wilson, Ph.D., a neuropsychologist at the Rush Alzheimer’s Disease Center.

The study also found that a higher level of education was associated with accelerated cogni-tive decline upon nursing home placement. Yet, day care use markedly reduced the association of education with accelerated cognitive decline in the nursing home; further evidence that there is a robust association between day care experience and cognition during the transition to a nursing home.

The authors considered the possibility that nursing home placement is simply a sign of in-creased severity of Alzheimer’s disease. Yet, the nursing-home-related increase in cognitive de-cline was observed even after simultaneous control for cognitive and noncognitive indicators of dementia severity at the time of nursing home entry.

Alternatively, the increased cognitive decline upon placement may reflect difficulty adapting to an unfamiliar environment, consistent with clinical reports of increased confusion and behav-ior problems in those with dementia during acute hospitalization or trips away from home. Pa-tients who had prior adult day care services may have been better able to adjust to the unfamil-iar environment.

“The findings suggest that the transition from the community to a nursing home is particularly difficult for people with Alzheimer’s disease and that those planning for their care should con-sider the possibility that experience in adult day care programs may help prepare affected per-sons for institutional living,” said Wilson.

The research was supported by grants from the National Institutes on Aging, which leads the federal effort supporting and conducting research on aging and the medical, social and behav-ioral issues of older people, including Alzheimer’s disease and age-related cognitive decline.

The Rush Alzheimer's Disease Center is one of approximately 30 NIA-supported Alzheimer's Disease Centers across the U.S. which conduct basic science, clinical, and social and behavioral

research on dementia and AD. General information on aging and aging research can be viewed at the NIA's home website, www.nia.nih.gov.

Brain inflammation may be friend, not foe, for Alzheimer's patientsNew findings fit well with vaccine approach to fight disease

Inflammation in the brain may not be so bad after all when it comes to Alzheimer’s disease.In the June 1 issue of the Journal of Clinical Investigation, a team of scientists from the Univer-

sity of Rochester Medical Center shows that a key inflammatory regulator, a known villain when it comes to parsing out damage after a stroke and other brain injuries, seems to do the opposite in Alzheimer’s disease, protecting the brain and helping get rid of clumps of material known as plaques that are a hallmark of the disease.

While many scientists have assumed that inflammation as a result of disease or injury only adds to the brain’s woes, the new findings show that the opposite may be true when it comes to Alzheimer’s disease. Perhaps inflammation is playing the role of protector and is acting more like an ambulance crew helping at the site of a road wreck, not causing the crash.

The work suggests that doctors not rush in to turn off molecular events that scientists have widely considered to be detrimental in people with the disease. The findings could also renew efforts to develop a vaccine or other strategies against Alzheimer’s by engaging the body’s im-mune system.

The team expected to see the telltale clumps of material known as amyloid plaques, made up of the peptide amyloid beta, worsen. Instead, to the team’s surprise, the brains of the mice with IL-1beta stuck in overdrive had only about half

“This work provides evidence that blocking all inflammatory responses in Alzheimer’s disease is not an ideal therapy,” added Shaftel. “This might hinder processes that are beneficial and part of the body’s adaptive response to fight plaques.”

The new findings hinge on a very special mouse that Shaftel spent three years creating with the guidance of his adviser, M. Kerry O’Banion, M.D., Ph.D., associate professor of Neurobiology and Anatomy. Shaftel genetically engineered a one-of-a-kind mouse that gives him pinpoint con-trol over brain levels of a human molecule known as interleukin-1beta, a well-recognized molec-ular kingpin in the realm of inflammation.

IL-1 beta, a signaling molecule that promotes brain inflammation, was one of the first mole-cules that scientists found in higher levels in the brains of people with Alzheimer’s disease com-pared to healthy people. It’s recognized as a critical player in bringing about much of the brain damage that follows a stroke and brain injury, so it’s no surprise that its presence in the brains of Alzheimer’s patients would be assumed to be part of the problem.

In the original development of his mouse, Shaftel worked closely with Stephanos Kyrkanides, D.D.S., Ph.D., associate professor in the Eastman Department of Dentistry and an expert on us-ing a class of viruses known as lentiviruses for use in gene therapy. The team used a lentivirus to boost levels of IL-1 beta in select brain regions of its engineered mouse, then applied the technology in mice specially designed to develop Alzheimer’s disease.

The mice developed normally for six months. Then Shaftel raised the level of IL-1beta in one part of the brain –the hippocampus, an area of the brain that specializes in memory and one of the first parts of the brain to be affected by the disease – and followed the mice for an additional month, watching for effects in the brain regions that were awash in higher-than-normal levels of IL-1beta. It’s the first use of an organism where scientists can boost IL-1beta in select areas and then watch what happens as the process unfolds.

The team expected to see the telltale clumps of material known as amyloid plaques, made up of the peptide amyloid beta, worsen. Instead, to the team’s surprise, the brains of the mice with IL-1beta stuck in overdrive had only about half as many plaques as mice without the over-active IL-1beta.

Through extensive experiments, the team showed that the mice simply weren’t making fewer plaques, but rather that the body was better at getting rid of the plaques. The team suspects the involvement of brain cells called microglia, the major immune cell that rushes to injury sites and helps repair and clean up wounds in the brain.

The work is the latest in a growing body of research that is trying to determine the exact role of inflammation in Alzheimer’s disease. O’Banion notes that some studies have found that taking medications to squelch inflammation, such non-steroidal anti-inflammatory drugs or NSAIDs, might help reduce a person’s chances of getting Alzheimer’s disease, while other studies, includ-ing a study of more than 2,100 people published in April, refute that notion.

“There is a great deal of evidence that inflammation plays a potentially negative role in Alzheimer’s disease,” said O’Banion. “But much of the evidence comes from experiments with

cells in a dish or postmortem human tissue, not from living organisms in which disease progres-sion is closely monitored.

“People have talked for a long time about a balance of ‘good guys’ and ‘bad guys’ within the inflammatory process, either causing harm or alleviating the disease. The current work rein-forces the idea that inflammation is not simply the bad guy that many people think it is.”

The work could have ramifications for the development of a vaccine or other strategy to pro-tect against or fight off Alzheimer’s. Work on an Alzheimer’s vaccine has at times been promis-ing, reducing the number of plaques in the brains of animals and a few people with the disease, but it’s also been fraught with difficulty, producing side effects such as encephalitis or severe brain inflammation in people with Alzheimer’s.

“The potential to treat Alzheimer’s disease by modulating the immune system is tremendous and is an area that has not been fully explored,” said O’Banion. “That said, people have to re-member that the current findings are in mice, not people. We need to be cautious about how to interpret the results.”

---------------------The project was part of Shaftel’s research to earn his doctoral degree as part of the University’s Medi-cal Scientist Training (M.D./Ph.D.) Program. He was awarded his doctoral degree for this work last month, and now he’ll spend the next two years completing medical school and earning his medical degree.In addition to Shaftel, O’Banion and Kyrkanides, authors include John Olschowka, Ph.D., associate professor of Neurobiology and Anatomy; and technical associates Jen-Nie Miller and Renee Johnson. The work was funded by the National Institute of Neurological Disorders and Stroke.University Hospitals Case Medical Center and Case Western Reserve University

School of Medicine to Conduct Innovative Smallpox Vaccine Research StudyCLEVELAND: University Hospitals Case Medical Center (UHCMC) and Case Western Reserve Univer-sity School of Medicine are part of a nationwide research study to determine the safety and ef-fectiveness of a new smallpox vaccine geared toward adults ages 18 to 34 who have never been vaccinated against the disease. The study is the first of its type in Northeast Ohio.

The current FDA-approved vaccine, Dryvax®, is not recommended for use on everyone be-cause of the potential for serious side effects in certain individuals. "For example, the current vaccine cannot be used in immune-compromised individuals, such as patients with HIV or indi-viduals with certain skin conditions such as eczema," says Robert A. Salata, M.D., chief of the Di-vision of Infectious Diseases at Case Western Reserve University School of Medicine and UHCMC.

The new vaccine, IMVAMUNE®, is different from Dryvax® in that it contains a more weakened form of the live-virus within the vaccine.

"Because the vaccine is weakened, the side effects should be minimized enough to give the vaccine to all individuals, even those whose immune systems are suppressed," says Dr. Salata. "Our hope is that the new vaccine will be a safer alternative to the current vaccine."

UHCMC and the School of Medicine will act as a subunit of St. Louis University's Center for Vaccine Development, which is one of seven national testing sites known as Vaccine and Treat-ment Evaluation Units (VTEUs), designated by the National Institute of Allergy and Infectious Dis-eases (NIAID), part of the National Institutes of Health.

The research study, which is actively recruiting and begins here June 15, will follow 215 volun-teers nationwide over a two-year period. Volunteers must be in general good health and must not have previously been vaccinated against smallpox.

Smallpox is a contagious and sometimes fatal infectious disease characterized by raised bumps that appear on the face and body of an infected person. There is no specific treatment for smallpox disease, and the only prevention is vaccination. The World Health Organization de-clared the disease eradicated in 1980 with the success of a worldwide vaccination program. Rou-tine vaccination against smallpox among the general public was ceased in 1972 because it was no longer necessary for prevention. However, recent threats of bioterrorism after 9/11 have spurred the development of a new safer vaccine that can be given to immune-compromised indi-viduals.For more information about the study and how to participate, call the Division of Infectious Diseases at 216-368-2003, or e-mail vaccinecenter@case.edu . Additional information can be found under the vaccine research unit link at http://www.cwru.id.org/ .

Smithsonian scientists connect climate change, origins of agriculture in Mexico

New charcoal and plant microfossil evidence from Mexico’s Central Balsas valley links a pivotal cultural shift, crop domestication in the New World, to local and regional environmental history. Agriculture in

the Balsas valley originated and diversified during the warm, wet, postglacial period following the much cooler and drier climate in the final phases of the last ice age. A significant dry period appears to have occurred at the same time as the major dry episode associated with the col-lapse of Mayan civilization, Smithsonian researchers and colleagues report in the Proceedings of the National Academy of Sciences online.

Cores from Laguna Tuxpan in Mexico's Iguala Valley, provided evidence for maize and squash cultivation along its edges by ~8000 B.P. and for the major dry event between

1800 and 900 B.P. Ruth Dickau“Our climate and vegetation studies reveal the ecological settings in which people domesti-

cated plants in southwestern Mexico. They also emphasize the long-term effects of agriculture on the environment,” said Dolores Piperno, curator of archaeobotany and South American ar-chaeology at the Smithsonian’s National Museum of Natural History and the Smithsonian Tropi-cal Research Institute in Panama.

Piperno’s co-authors include Enrique Moreno and Irene Holst, research assistants at STRI; Jose Iriarte, lecturer in archaeology at the University of Exeter in England; Matthew Lachinet, assis-tant professor at the University of Nevada in Las Vegas; John Jones, assistant professor at Wash-ington State University; Anthony Ranere, professor at Temple University; and Ron Castanzo, re-search collaborator at the National Museum of Natural History.

Pollen of Podocarpus, a conifer now found primarily at higher elevations, is common in the old-est strata of sediment cores taken from lakes and a swamp in the central Balsas watershed. Along with pollen from grasses and other dryland plants, the Podocarpus indicates the environ-ment encountered by humans at the end of the last ice age (14,000-10,000 B.P.) was drier and 4 or 5 degrees Centigrade cooler than it is today.

The Balsas valley is one of the most likely sites for the domestication of corn (Zea mays) from its wild ancestor, teosinte (Zea mays ssp. parviglumis) because populations of modern teosinte from that region are genetically closest to maize. As the lakes formed beginning around 10,000 B.P., they became magnets for human populations who exploited the fertile soils and rich aquatic resources the lakes contained. The researchers found prehistoric pottery sherds and other artifacts in sediments at the edges of the lakes. At one lake, phytolith data shows that maize and squash were probably planted at the fertile edges by 8000 B.P. Pollen from teosinte is indistinguishable from that of maize, but Zea pollen is consistently present in the cores since the end of the last ice age.

Pollen and phytoliths from weeds associated with crop plants become plentiful in the cores at roughly 6300 B.P Charcoal associated with agricultural burning practices also is abundant at that time. Between 1800 B.P. and 900 B.P., a major drying event occurred, corresponding to the time when a drought occurred in the region of the Classic Mayan civilization. This evidence shows that even during the Holocene, severe, short-term climatic oscillations occurred that may have had considerable importance for social change.

“We continue to find that tropical forests played a much more important role in the origin of agriculture in the New World than was once thought,” Piperno said.

Flaxseed stunts the growth of prostate tumorsDURHAM, N.C. -- Flaxseed, an edible seed that is rich in omega 3-fatty acids and fiber-related com-pounds known as lignans, is effective in halting prostate tumor growth, according to a study led by Duke University Medical Center researchers. The seed, which is similar to a sesame seed, may be able to interrupt the chain of events that leads cells to divide irregularly and become cancerous.

"Our previous studies in animals and in humans had shown a correlation between flaxseed supplementation and slowed tumor growth, but the participants in those studies had taken flaxseed in conjunction with a low-fat diet," said Wendy Demark-Wahnefried, Ph.D., a researcher in Duke's School of Nursing and lead investigator on the study. "For this study, we demonstrated that it is flaxseed that primarily offers the protective benefit."

The researchers will present their results on Saturday, June 2, during a news briefing at the annual meeting of the American Society of Clinical Oncology, in Chicago. The multisite study, which was funded by the National Institutes of Health, also involved researchers at the Univer-sity of Michigan and the University of North Carolina at Chapel Hill.

In the study, the researchers examined the effects of flaxseed supplementation on men who were scheduled to undergo prostatectomy -- surgery for the treatment of prostate cancer. The men took 30 grams of flaxseed daily for an average of 30 days prior to surgery. Once the men's tumors were removed, the researchers looked at tumor cells under a microscope, and were able to determine how quickly the cancer cells had multiplied.

Men taking flaxseed, either alone or in conjunction with a low-fat diet, were compared to men assigned to just a low-fat diet, as well as to men in a control group, who did not alter or supple-ment their daily diet. Men in both of the flaxseed groups had the slowest rate of tumor growth, Demark-Wahnefried said. Each group was made up of about 40 participants.

Study participants took the flaxseed in a ground form because flaxseed in its whole form has an undigestible seed coat, she said. Participants elected to mix it in drinks or sprinkle it on food, such as yogurt.

"The results showed that the men who took just flaxseed as well as those who took flaxseed combined with a low-fat diet did the best, indicating that it is the flaxseed which is making the difference," Demark-Wahnefried said.

Flaxseed is thought to play a part in halting the cellular activity that leads to cancer growth and spread. One reason could be that as a source of omega-3 fatty acids, flaxseed can alter how cancer cells lump together or cling to other body cells, both factors in how fast cancer cells pro-liferate, Demark-Wahnefried said. The researchers also suspect that lignans may have antiangio-genic properties, meaning they are able to choke off a tumor's blood supply, stunting its growth.

"We are excited that this study showed that flaxseed is safe and associated with a protective effect on prostate cancer," Demark-Wahnefried said.

The researchers hope to next test the effectiveness of flaxseed supplementation in patients with recurrent prostate cancer, and ultimately to study its role as a preventative agent.

----------One out of six American men will develop prostate cancer. More than 218,000 men are expected to be diagnosed with the disease in 2007, according to the American Cancer Society, and about 27,000 will die from it.Gene variations point to why lung cancer drugs work better in Japanese vs. US

patientsDNA analysis reveals why patients react differently to two commonly used drugs

ANN ARBOR, Mich. — Last year, a groundbreaking international project found that a group of Japa-nese patients with advanced non-small cell lung cancer survived longer —and had a higher rate of side effects — than U.S. patients with the same diagnosis,.when both groups were given two well-known drugs for the disease.

Now, a follow-up study suggests the reasons appear to lie in subtle variations in certain genes that govern how the body metabolizes chemotherapy drugs. David Gandara, M.D., a University of California, Davis researcher who led the recent Southwest Oncology Group study, will present the results Saturday, June 2, at the American Society of Clinical Oncology annual meeting.

The discovery that Japanese and U.S. patients, matched in age, gender and other respects, had differences in key metabolism-related genes is the latest result from a seven-year collabora-tion between the Southwest Oncology Group and two clinical trials groups in Japan. Gandara, who leads lung cancer trial efforts for the Southwest Oncology Group, is director of clinical re-search at the University of California, Davis, Cancer Center. The Southwest Oncology Group (SWOG) is the largest federally funded U.S. cancer trials network.

The recent SWOG study breaks new ground by exploring the possible role of ethnic patterns in the emerging science of pharmacogenomics, which promises to tailor drug regimens to a pa-tient’s genetic profile. “Nobody else in the world has ever done this, with a common arm looking at genetic differences among ethnic groups,” Gandara says.

Researchers looked at DNA from 156 patients who received the chemotherapy drugs pacli-taxel and carboplatin in a SWOG clinical trial and one conducted by the Japan Multicenter Trial Organization. In the trials, half the Japanese patients survived one year, while slightly more than one-third of U.S. patients did. The Japanese patients as a group survived longer despite the fact that a significant number of them had to be given a lower dose of paclitaxel and for a shorter time than the U.S. patients because of toxicity. The U.S. group was predominantly Caucasian; 2 percent were Asian-Americans.

To find clues to the differences, the scientists examined six genes in DNA samples from the patients. They found differences in four. In patients with certain variations in the CYP3A4 gene, it took 2.75 times longer for their lung cancer to progress than in patients without the variations. A variation in another gene, ERCC2, appeared to interfere with how well patients responded to treatment.

The differences in outcomes corresponded with the patients’ genetic makeup, rather than their ethnicity per se, since. some individuals in each group possessed genetic variations not typical of their group. Thus, the study suggests therapies in the future need to be tailored to each individual based on analysis of his or her genetic makeup, not simply ethnicity.

The relatively small number of patients makes the results of the study far from conclusive: Gandara calls the study “hypothesis-generating.” Next, he and other SWOG scientists are seek-ing funding to learn what genes may explain why Japanese and U.S. patients respond differently to EGFR inhibitors such as erlotinib, a relatively new targeted therapy that is another important class of drugs for lung cancer.

Herb shows potential to reduce cancer-related fatigueNorth Central Cancer Treatment Group reports on pilot ginseng study

CHICAGO -- North Central Cancer Treatment Group (http://ncctg/) (NCCTG) researchers, based at Mayo Clinic in Rochester, Minn., have generated preliminary data suggesting that a form of American ginseng provides greater improvements in fatigue and vitality in patients who receive the highest doses tested, compared to lower doses or no treatment.

The results of their scientifically rigorous pilot study, the first to evaluate the Wisconsin species of American ginseng as a possible therapy for cancer-related fatigue, are being pre-sented June 3 at the annual meeting of the American Society of Clinical Oncology.

Many cancer patients face extreme fatigue after diagnosis and during treatment. Getting more sleep or rest often does not relieve the fatigue, nor is it related to activity levels. Other than exercise, there isn’t a good solution available for these patients.

“We hope that Wisconsin ginseng may offer us a much-needed treatment to improve our pa-tients’ quality of life, and we look forward to further evaluation,” says Debra Barton, Ph.D. (http://mayoresearch.mayo.edu/mayo/research/staff/barton_dl.cfm), a registered nurse, Mayo Clinic cancer researcher (http://cancercenter.mayo.edu/) and the study’s primary investigator.

“Cancer-related fatigue is one of the most profound and distressing issues patients face,” she says. This unique type of fatigue can have dozens of causes, and for patients who have com-pleted cancer therapy, fatigue is among their foremost concerns, second only to fear of disease recurrence.”

Traditional Chinese medicine and current understanding of ginseng’s function both point to its characteristics as an adaptogen -- a substance that helps the body overcome the effects of envi-ronmental stress. Since cancer patients have stressors ranging from the psychological stress of diagnosis to the physiological stresses of chemotherapy and radiation, if ginseng helps, the re-searchers think it would be a valuable addition to currently available therapies.

“With animal data indicating the possibilities of ginseng with respect to increased swimming endurance, and the availability and verified product quality of Wisconsin ginseng, we decided to move forward with a pilot study,” says Dr. Barton.

The investigators enrolled 282 patients in a randomized, placebo-controlled trial, averaging 71 patients per each of four arms, with between 39 and 48 patients in each arm completing the eight weeks of treatment. Treatment arms consisted of placebo, and three different daily doses of Wisconsin ginseng -- 750, 1,000 and 2,000 milligrams.

Of the four treatment arms, patients receiving the placebo and the lowest dose of ginseng re-ported very little improvement in fatigue or other areas of physical or psychological well-being. The patients receiving the larger doses showed improvements in overall energy levels, reporting higher vitality levels and less interference with activity from fatigue. They also reported an im-provement in overall mental, physical, spiritual and emotional well-being.

Because this was a pilot trial designed to pinpoint which aspects of fatigue ginseng might help alleviate, determine likely dosage options, and identify possible side effects, Dr. Barton cautions against immediate addition of ginseng supplements to any patient’s therapeutic regimen. “While results were promising, we have more research to conduct,” she says. “And besides, it’s just not a good idea to grab the nearest bottle on the supermarket shelf — consumers need to research the company and the product. Because there is less federal regulation of dietary supplements, there is no consistency in currently available products. In fact, some research has shown various supplements to contain little or no amount of the ingredient on the label, and sometimes even harmful contaminants.”

Dr. Barton’s research team hopes to open a new clinical trial in 2008 looking at a specific dose of Wisconsin ginseng versus placebo and trying to better refine the results, in hopes of a con-firming a new treatment option for cancer-related fatigue.

According to the National Center for Health Statistics (http://www.cdc.gov/nchs/), Americans spend between $36 billion and $47 billion per year on complementary and alternative therapies, including herbal supplements. A recent study (http://www.mayoclinicproceedings.com/Abstrac-t.asp?AID=4359&Abst=Abstract&UID=) authored by Mayo Clinic resident Aditya Bardia, M.D., re-ports that two-thirds of people who use herbs do not use any scientific evidence-based informa-tion to guide their purchases. To aid consumers in their decision-making process, Mayo Clinic re-cently published a book addressing current knowledge regarding a number of complementary

and alternative therapies. The Mayo Clinic Book of Alternative Medicine (http://bookstore.may-oclinic.com/products/bookDetails.cfm?mpid=35) dispels myths and sheds light on therapies that have been scientifically studied for safety and effectiveness.

MACHO matter is running out of places to hide* 11:45 01 June 2007

* NewScientist.com news service* Maggie McKee, Honolulu

"Dark objects" lurking in the outskirts of the Milky Way are running out of places to hide. As-tronomers have successfully measured the distance to one such object - probably a pair of orbit-ing black holes - for the first time, by triangulating observa-tions made on Earth and in space.

The novel technique could reveal how many of these dark objects are out there.

At least 80% of the Milky Way's mass is dark matter. Most of that takes an exotic, as-yet-unknown form, but some is thought to be made up of relatively familiar objects - such as stars and black holes - that are simply too faint to see. Scat-tered in the outer reaches of the galaxy, they are called mas-sive compact halo objects (MACHOs).

The only way to spot them is to wait for a one to pass be-tween the Earth and a distant star. The MACHO’s gravity will bend the light of the star like a lens, making it appear brighter for several weeks or months. Astronomers took advantage of the wide separation between the Spitzer Space Telescope and Earth to measure the distance to a dark object in the outer reaches of the Milky Way

NASA/JPL-Caltech/T Pyle/SSC)Two eyes are better than one

Unfortunately, different groups searching for this effect have come to drastically different con-clusions about whether any MACHOs have been detected, with one team saying it has seen about a dozen events, and another reporting it has seen none.

Much of the confusion stems from the fact that standard observations do not reveal the dis-tance to the dim objects, leaving researchers in the dark about whether they lie in our galaxy - and thereby qualify as MACHOs - or in neighbouring galaxies.

"Our method has the potential to disentangle this and solve the mystery," says team member Subo Dong of Ohio State University in Columbus, US.

The new method pinpoints the distance to the candidate MACHO by comparing the views out of each of two "eyes", one on Earth, the other in space

A 1.3-metre telescope in Chile called OGLE discovered the telltale brightening of a background star in 2005. Astronomers then commanded the Spitzer Space Telescope, then 30 million kilome-tres from Earth, to turn its eye towards the event. Spitzer saw the same star brightening slowly, but with a slight time delay.

The delay is just the length that astronomers would expect if the two events were caused by an object in our galactic halo - which typically move at a few hundred kilometres per second - crossing over the two separate lines of sight.Gravitational clues

It is probably no more than about 16,000 light years from Earth, says team leader Andrew Gould of Ohio State University, although there is still a 5% chance the pair of objects may lie out in the Small Magellanic Cloud galaxy, home of the background star that was brightened.

By the way the brightness of the background star's light fluctuated slightly over the course of the year-long lensing event, the team determined that the dark object was actually composed of two bodies: one about seven times the Sun's mass, and the other about 3.5 times.

Stars so heavy would be visible, if they are indeed within our halo. Since they are not visible, the researchers say the dark pair may actually be two black holes in orbit around each other - a duo that could only be detected from their gravitational lensing effect.

With a single observation, Dong says it is not yet possible to say how much MACHOs contrib-ute to the Milky Way's dark matter. "But with more events, we will be able to further understand the composition of the dark matter halo in the form of MACHOs," he says.

He presented the research on Wednesday, at a meeting of the American Astronomical Society in Honolulu, Hawaii, US.

Folic acid could protect against strokes* 12:23 01 June 2007

* NewScientist.com news service* Roxanne Khamsi

Folic acid supplements can reduce the risk of stroke by 30%, according to a review of eight studies involving nearly 17,000 participants.

The new findings will add fuel to growing calls for the B vitamin to be routinely added to flour or bread - to protect against birth defects - in countries such as the UK where this is not already practice.

Opponents point out that an increase in folic acid can mask a vitamin B12 deficiency which can be dangerous in the elderly.

Xiaobin Wang at the Children's Memorial Research Center in Chicago, Illinois, US, and col-leagues combined existing data from trials looking at the vitamin's effect on cardiovascular dis-ease.

The studies, in which people aged around 60 received either placebo pills or daily folic acid supplements, followed participants for between two to six years.Small dose sufficient

Those taking supplements in the trials received between 0.5 milligrams and 15 mg. Health officials in the US recommend a daily intake of at least 0.4 milligrams of folic acid - about the amount in a bowl of fortified cereal.

The analysis revealed that taking any amount of folic acid lowered the risk of stroke by 18%. Another analysis looking specifically at the effect in countries that do not fortify grain with folic acid, such as Norway, China and Italy, found a 25% drop in stroke among those taking the sup-plement.

When Wang analysed a subgroup of those who took the supplements for at least three years, she found that folic acid reduced the risk of stroke by almost 30%.

Unexpectedly, those who received the smallest dose of folic acid benefited just as much as those who received the largest amounts. Wang believes this is because the body needs only a certain crucial amount of the vitamin.Cardiovascular risk

"If you have a person who has never had a stroke before, they may benefit," says Cynthia Carlsson of the University of Wisconsin School of Medicine in Madison, US, who was not involved in the study.

She cautions, however, that people with a history of cardiovascular disease might want to steer clear of folic acid supplements, since previous studies have suggested it may slightly ele-vate the risk of heart attack.

How folic acid protects against stroke remains unclear. It is known that the vitamin helps the body excrete homocysteine, a by-product of protein breakdown that effects small blood vessels, and which has been linked to heart disease and dementia. Journal reference: Lancet (vol 369, p 1876)

Ice Age Ends Smashingly: Did a comet blow up over eastern Canada?Sid Perkins

Evidence unearthed at more than two dozen sites across North America suggests that an ex-traterrestrial object exploded in Earth's atmosphere above Canada about 12,900 years ago, just as the climate was warming at the end of the last ice age. The explosion sparked immense wildfires, devastated North America's ecosystems and prehistoric cultures, and triggered a mil-lennium-long cold spell, scientists say.

At sites stretching from California to the Carolinas and as far north as Alberta and Saskatchewan—many of which were home to prehistoric people of the Clovis culture—re-searchers have long noted an enigmatic layer of carbon-rich sediment that was laid down nearly 13 millennia ago. "Clovis artifacts are never found above this black mat," says Allen West, a geophysicist with Geoscience Consult-ing in Dewey, Ariz. The layer, typically a few millimeters thick, lies between older, underlying strata that are chock-full of mammoth bones and younger, fossilfree sediments immediately above, he notes.

IT'S IN THERE. A layer of carbon-rich sediment (arrow) found here at Murray Springs, Ariz., and elsewhere across North America, provides evidence that an extraterrestrial ob-ject blew up over Canada 12,900 years ago. The hallmarks include lumps of glasslike car-

bon (top), carbon spherules (middle, in cross section), and magnetic grains rich in iridium (bottom).

West; (middle inset): Cannon MicroprobeNew analyses of samples taken from 26 of those sites reveal several hallmarks of an extrater-

restrial object's impact, West and his colleagues reported at the spring meeting of the American Geophysical Union in Acapulco, Mexico.

Samples from the base of the black mat yield most of the clues to its extraterrestrial origin, says Richard B. Firestone, West's coworker and a nuclear physicist at the Lawrence Berkeley (Calif.) National Laboratory. Some of the particles there are small, magnetic grains of material with higher proportions of iridium than are found in Earth's crust, he notes.

Also in the mat's base are tiny lumps of glasslike carbon that probably formed from molten droplets of the element. These lumps, as well as little spheres of carbon with a different mi-crostructure, contain nanoscale diamonds formed under intense pressure.

A host of unusual geological features, collectively known as Carolina Bays, hints at the cata-clysm's location, says team member George A. Howard, a wetland manager at Restoration Sys-tems, an environmental-restoration firm in Raleigh, N.C. Around 1 million of these elliptical, sand-rimmed depressions, measuring between 50 meters and 11 kilometers across, scar the landscape from New Jersey to Florida. In samples taken from 15 of the features, Howard and his colleagues found iridium-rich magnetic grains and carbon spherules with tiny diamond frag-ments similar to those found at Clovis archaeological sites.

The long axes of the great majority of the Carolina Bays point toward locations near the Great Lakes and in Canada—a hint that the extraterrestrial object disintegrated over those locales, says Howard.

Because scientists "haven't discovered a large, smoking hole" left by the event, the object that blew up in the atmosphere probably was a comet, says West.

Heat from the event would have set off wildfires across the continent, the scientists suggest. The heat and shock from the explosion probably broke up portions of the ice sheet smothering eastern Canada at the time, they add. The flood of fresh water into the North Atlantic that re-sulted would have interrupted ocean currents that bring warmth to the region, and thick clouds of smoke and soot in the air would have intensified cooling across the Northern Hemisphere.

The inferred date of the event matches the beginning of a 1,200-year-long cold spell that ge-ologists call the Younger Dryas, which in its first few decades saw temperatures in the Northern Hemisphere drop as much as 10°C.

Tea—Milking ItJanet Raloff

I'm a serious tea drinker. I'll down it hot or cold, plain or with lemon. Like most Americans, however, I don't regularly add milk. But when my colleague David Lindley, an editor here at Sci-ence News, was growing up, his family certainly did.

Being a Brit, David comes from a culture that holds considerable reverence for this brew and might be accused of being fussy about its preparation. When I add milk to tea, which I do only occasionally, I'm not careful about the amount. It's typically a big slosh—and always added after the tea is fully brewed and sitting in a mug.

In the Lindley household, by contrast, "a little milk was put into the bottom of a cup—just a touch," before any tea was added, David notes. And his mom invariably made tea in the pot, brewing it from some black, loose-leaf variety.

Because adding milk to tea is routine in the United Kingdom, a team of Scottish researchers decided to investigate the potential health significance of this practice. Their concern: Because milk can bind to some of tea's antioxidants, it might prevent them from countering free radicals.

These radicals can wreak havoc on DNA and other components of cells. And with the on-slaught of age, disease, and pollutant exposures, our bodies find it harder to keep those radicals in check. The result: Studies have begun linking excessive free-radical production to a host of chronic disorders, from cancer and diabetes to heart disease.

Against this backdrop, Janet A.M. Kyle and her colleagues at the Rowett Research Institute purchased different teas from local stores, brewed them up, and then assayed their antioxidant activity. In a paper published online and in an upcoming Journal of Agricultural and Food Chem-istry, they report finding some brand-related differences in the inherent antioxidant activity of a brew. The good news: Adding milk doesn't alter that activity.

Moreover, they found, adding milk to tea doesn't diminish the amount of antioxidants—such as the epigallocatechin gallate, which many commercial teas tout as EGCG—that ends up in tea-drinkers' blood. So, it appears one can safely boost the protein content of your brew, by adding milk, without sacrificing tea's antioxidant bounty.

Rich in antioxidantsWhen it comes to quashing free radicals, tea provides an antioxidant bonanza. Best known are

its catechins, a family of compounds whose star, EGCG, has been linked not only to weight loss but also to diminished cancer risk.

Teas also contain polyphenolic chemicals, another class of antioxidant compounds that ap-pear capable of lowering an individual's risk of heart disease and cancer. Tea's chief polyphenol constituents are quercetin and kaempferol. However, because milk can bind to these, there had been concern that such chemical pairings might limit the polyphenols' biological activity or even their uptake by the body.

To test that, Kyle's group purchased six locally popular teas and evaluated the composite an-tioxidant activity of each. They boiled water and added 3 grams of tea leaves—the amount in a typical U.K. tea bag, but 50 percent more than is found in typical European tea bags—for each brewed cup. Chemical assays showed that the brews' levels of polyphenols and catechins rose steadily for about 7 minutes.

"Except for the cheapest supermarket brand," Kyle notes, "we got similar results for these teas." The low-cost outlier proved lower than the name brands in terms of the free-radical-quenching punch it delivered, mostly owing to its low concentrations of polyphenols.

The researchers selected the tea that had exhibited the strongest antioxidant performance for their follow-up human trials. On three separate occasions, each of 9 healthy men in their mid-20s to mid-30s avoided tea for at least a day, fasted overnight, and then drank a test beverage for breakfast.

On one morning, each man got two cups of black tea that had been steeped for 7 minutes. To-gether, the cups contained 300 ml of tea mixed with 100 ml of hot water. Another day, volun-teers got 300 ml of tea mixed with 100 ml of skim milk. On the remaining test day, each recruit downed 300 ml of hot water that had been doctored with 100 ml of milk. (Didn't the latter taste ghastly? "It did," Kyle concedes, "and I'm very grateful to my volunteers for actually drinking it.")

Before and at various points over a 3-hour period following the consumption of each day's beverage, Kyle's group sampled the volunteers' blood to measure polyphenols, catechin levels, and the blood's ability to quash free radicals. While the gross, milky hot water had no effect on these parameters, both brews showed equivalent increases in circulating antioxidants and radi-cal-thwarting prowess, which peaked about 60 minutes after tea had been consumed.

Kyle says her group now hopes to examine tea's antioxidant performance in a larger group of people and for a longer period. She's hoping it proves substantial because the only other source of the antioxidant chemicals being looked at in her study come from fruits and vegetables—and "we don't eat a lot of those in Scotland," she says, "but we do drink a lot of tea."

And what about David: After 24 years in the United States, does he still blend a touch of milk with his tea? No, he says. Milk is for black tea, which doesn't much agree with his constitution. Today, his brews are "mostly green and herbal teas."By the way, David's not just one of our editors. The author-physicist also has 6 books under his belt. On Feb. 20, Doubleday published his latest—Uncertainty: Einstein, Heisenberg, Bohr, and the Strug-gle for the Soul of Science.Editor's note: David Lindley played no role in assigning or editing this article.