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Work It Out: More Activity = Slower Aging

New study links exercise to greater longevity

 
AGING FAST A new study shows that lack of exercise may speed the aging process

Warning, couch potatoes: resting on your laurels may be hazardous to your health, not to mention make you old before your time.

"A sedentary lifestyle increases the propensity to aging-related disease and premature death," researchers at King's College London report today in the journal Archives of Internal Medicine. "Inactivity may diminish life expectancy not only by predisposing to aging-related diseases but also because it may influence the aging process itself."

Researcher Lynn Cherkas and colleagues reached their conclusions by examining the genetic material extracted from blood samples of some 2,400 twins. They specifically studied the length of telomeres (repeated DNA sequences) on the ends of chromosomes in leukocytes (white blood cells); the protective caps are believed to be markers of biological aging, because they shrink over time.

Their findings: the telomeres of subjects who exercised the most (an average of 199 minutes weekly) were longer than those of volunteers who worked out the least (a mere 16 minutes or less a week). The discrepancy was enough, researchers wrote, to suggest that the exercise mavens were on average as much as a decade biologically younger than the slackers.

"Such a relationship between leukocyte telomere length and physical activity level remained significant after adjustment for body mass index, smoking, socioeconomic status and physical activity at work," the authors report. "The mean difference in leukocyte telomere length between the most active and least active subjects was 200 nucleotides (chemical structural units of DNA and RNA), which means that the most active subjects had telomeres the same length as sedentary individuals up to 10 years younger, on average."

The scientists speculate that stress, inflammation and oxidative stress (cell damage caused by oxygen exposure) may be responsible for shortened telomeres in physically inactive people. Exercise is among the factors found to help alleviate stress. Previous research has linked regular workouts to lower rates of cardiovascular disease, type 2 diabetes, cancer, high blood pressure, obesity and osteoporosis.

The researchers note that their findings support U.S. guidelines calling for individuals to exercise moderately for 30 minutes at least five days a week. "Our results. . . show that adults who partake in regular physical activity are biologically younger than sedentary individuals," they say. "This conclusion provides a powerful message that could be used by clinicians to promote the potential anti-aging effect of regular exercise."

PR
Regulator orders drug companies to study suicide risk during trials

After decades of inattention to the possible psychiatric side effects of experimental medicines, the U.S. Food and Drug Administration is requiring drug makers to study closely whether patients become suicidal during clinical trials.

The new rules represent one of the most profound changes of the past 16 years in regulations governing drug development in the United States. But since the regulator's oversight of experimental medicines is done in secret, the agency's shift has not been announced publicly.

The drug industry, however, is keenly aware of the change. For the first time, the agency is asking makers of drugs dealing with obesity, urinary incontinence, epilepsy, smoking cessation, depression and many other conditions to put comprehensive suicide assessments into their clinical trials.

In recent months, the agency has sent letters - it would not say how many - to drug makers requiring that they use such a scale. Merck, Sanofi-Aventis and Eli Lilly are all using a detailed suicide assessment in clinical trials being conducted now.

The seeds for the new U.S. effort were planted four years ago with the discovery that antidepressants might cause some children and teenagers to become suicidal. Top agency officials at first discounted the finding but commissioned researchers from the Columbia University department of psychiatry, led by Kelly Posner, to reanalyze the drugs' clinical trials. This work led the drug agency and its experts to view the risk as real.

Then it received an application for rimonabant, a much-heralded obesity drug developed by Sanofi-Aventis, the French drug giant. As agency medical reviewers pored over the drug's clinical trial data, they discovered hints that it could cause psychiatric problems, too.

Unsettled by their experience with antidepressants, agency reviewers again ordered the use of Posner's system. The assessment found that the drug doubled the risk of suicidal symptoms. In June, an agency advisory committee voted unanimously that the regulator reject rimonabant because of its psychiatric effects, and Sanofi-Aventis withdrew the application, although the drug is sold in Europe.

Just this month, published results of a trial of Merck's obesity drug taranabant showed similar psychiatric problems.

Fears have grown that drugs used to treat epilepsy, seizures and mood disorders may have similar effects. Examination of these medicines by the agency should be completed this year.

Suddenly, agency officials realized that multiple classes of medicines might cause dangerous psychiatric problems.

"Clearly we were somewhat surprised when this signal emerged in the pediatric antidepressant data," said Dr. Thomas Laughren, the drug agency's director of the division of psychiatry products. "So various groups within FDA are now looking at suicidality more broadly as a possible adverse event."

Rethinking the Meat-Guzzler

It’s meat.

The two commodities share a great deal: Like oil, meat is subsidized by the federal government. Like oil, meat is subject to accelerating demand as nations become wealthier, and this, in turn, sends prices higher. Finally — like oil — meat is something people are encouraged to consume less of, as the toll exacted by industrial production increases, and becomes increasingly visible.

Global demand for meat has multiplied in recent years, encouraged by growing affluence and nourished by the proliferation of huge, confined animal feeding operations. These assembly-line meat factories consume enormous amounts of energy, pollute water supplies, generate significant greenhouse gases and require ever-increasing amounts of corn, soy and other grains, a dependency that has led to the destruction of vast swaths of the world’s tropical rain forests.

Just this week, the president of Brazil announced emergency measures to halt the burning and cutting of the country’s rain forests for crop and grazing land. In the last five months alone, the government says, 1,250 square miles were lost.

The world’s total meat supply was 71 million tons in 1961. In 2007, it was estimated to be 284 million tons. Per capita consumption has more than doubled over that period. (In the developing world, it rose twice as fast, doubling in the last 20 years.) World meat consumption is expected to double again by 2050, which one expert, Henning Steinfeld of the United Nations, says is resulting in a “relentless growth in livestock production.”

Americans eat about the same amount of meat as we have for some time, about eight ounces a day, roughly twice the global average. At about 5 percent of the world’s population, we “process” (that is, grow and kill) nearly 10 billion animals a year, more than 15 percent of the world’s total.

Growing meat (it’s hard to use the word “raising” when applied to animals in factory farms) uses so many resources that it’s a challenge to enumerate them all. But consider: an estimated 30 percent of the earth’s ice-free land is directly or indirectly involved in livestock production, according to the United Nation’s Food and Agriculture Organization, which also estimates that livestock production generates nearly a fifth of the world’s greenhouse gases — more than transportation.

To put the energy-using demand of meat production into easy-to-understand terms, Gidon Eshel, a geophysicist at the Bard Center, and Pamela A. Martin, an assistant professor of geophysics at the University of Chicago, calculated that if Americans were to reduce meat consumption by just 20 percent it would be as if we all switched from a standard sedan — a Camry, say — to the ultra-efficient Prius. Similarly, a study last year by the National Institute of Livestock and Grassland Science in Japan estimated that 2.2 pounds of beef is responsible for the equivalent amount of carbon dioxide emitted by the average European car every 155 miles, and burns enough energy to light a 100-watt bulb for nearly 20 days.

Grain, meat and even energy are roped together in a way that could have dire results. More meat means a corresponding increase in demand for feed, especially corn and soy, which some experts say will contribute to higher prices.

This will be inconvenient for citizens of wealthier nations, but it could have tragic consequences for those of poorer ones, especially if higher prices for feed divert production away from food crops. The demand for ethanol is already pushing up prices, and explains, in part, the 40 percent rise last year in the food price index calculated by the United Nations’ Food and Agricultural Organization.

Though some 800 million people on the planet now suffer from hunger or malnutrition, the majority of corn and soy grown in the world feeds cattle, pigs and chickens. This despite the inherent inefficiencies: about two to five times more grain is required to produce the same amount of calories through livestock as through direct grain consumption, according to Rosamond Naylor, an associate professor of economics at Stanford University. It is as much as 10 times more in the case of grain-fed beef in the United States.

The environmental impact of growing so much grain for animal feed is profound. Agriculture in the United States — much of which now serves the demand for meat — contributes to nearly three-quarters of all water-quality problems in the nation’s rivers and streams, according to the Environmental Protection Agency.

Because the stomachs of cattle are meant to digest grass, not grain, cattle raised industrially thrive only in the sense that they gain weight quickly. This diet made it possible to remove cattle from their natural environment and encourage the efficiency of mass confinement and slaughter. But it causes enough health problems that administration of antibiotics is routine, so much so that it can result in antibiotic-resistant bacteria that threaten the usefulness of medicines that treat people.

Those grain-fed animals, in turn, are contributing to health problems among the world’s wealthier citizens — heart disease, some types of cancer, diabetes. The argument that meat provides useful protein makes sense, if the quantities are small. But the “you gotta eat meat” claim collapses at American levels. Even if the amount of meat we eat weren’t harmful, it’s way more than enough.

Americans are downing close to 200 pounds of meat, poultry and fish per capita per year (dairy and eggs are separate, and hardly insignificant), an increase of 50 pounds per person from 50 years ago. We each consume something like 110 grams of protein a day, about twice the federal government’s recommended allowance; of that, about 75 grams come from animal protein. (The recommended level is itself considered by many dietary experts to be higher than it needs to be.) It’s likely that most of us would do just fine on around 30 grams of protein a day, virtually all of it from plant sources .

What can be done? There’s no simple answer. Better waste management, for one. Eliminating subsidies would also help; the United Nations estimates that they account for 31 percent of global farm income. Improved farming practices would help, too. Mark W. Rosegrant, director of environment and production technology at the nonprofit International Food Policy Research Institute, says, “There should be investment in livestock breeding and management, to reduce the footprint needed to produce any given level of meat.”

Then there’s technology. Israel and Korea are among the countries experimenting with using animal waste to generate electricity. Some of the biggest hog operations in the United States are working, with some success, to turn manure into fuel.

Longer term, it no longer seems lunacy to believe in the possibility of “meat without feet” — meat produced in vitro, by growing animal cells in a super-rich nutrient environment before being further manipulated into burgers and steaks.

Another suggestion is a return to grazing beef, a very real alternative as long as you accept the psychologically difficult and politically unpopular notion of eating less of it. That’s because grazing could never produce as many cattle as feedlots do. Still, said Michael Pollan, author of the recent book “In Defense of Food,” “In places where you can’t grow grain, fattening cows on grass is always going to make more sense.”

But pigs and chickens, which convert grain to meat far more efficiently than beef, are increasingly the meats of choice for producers, accounting for 70 percent of total meat production, with industrialized systems producing half that pork and three-quarters of the chicken.

Once, these animals were raised locally (even many New Yorkers remember the pigs of Secaucus), reducing transportation costs and allowing their manure to be spread on nearby fields. Now hog production facilities that resemble prisons more than farms are hundreds of miles from major population centers, and their manure “lagoons” pollute streams and groundwater. (In Iowa alone, hog factories and farms produce more than 50 million tons of excrement annually.)

These problems originated here, but are no longer limited to the United States. While the domestic demand for meat has leveled off, the industrial production of livestock is growing more than twice as fast as land-based methods, according to the United Nations.

Perhaps the best hope for change lies in consumers’ becoming aware of the true costs of industrial meat production. “When you look at environmental problems in the U.S.,” says Professor Eshel, “nearly all of them have their source in food production and in particular meat production. And factory farming is ‘optimal’ only as long as degrading waterways is free. If dumping this stuff becomes costly — even if it simply carries a non-zero price tag — the entire structure of food production will change dramatically.”

Animal welfare may not yet be a major concern, but as the horrors of raising meat in confinement become known, more animal lovers may start to react. And would the world not be a better place were some of the grain we use to grow meat directed instead to feed our fellow human beings?

Real prices of beef, pork and poultry have held steady, perhaps even decreased, for 40 years or more (in part because of grain subsidies), though we’re beginning to see them increase now. But many experts, including Tyler Cowen, a professor of economics at George Mason University, say they don’t believe meat prices will rise high enough to affect demand in the United States.

“I just don’t think we can count on market prices to reduce our meat consumption,” he said. “There may be a temporary spike in food prices, but it will almost certainly be reversed and then some. But if all the burden is put on eaters, that’s not a tragic state of affairs.”

If price spikes don’t change eating habits, perhaps the combination of deforestation, pollution, climate change, starvation, heart disease and animal cruelty will gradually encourage the simple daily act of eating more plants and fewer animals.

Mr. Rosegrant of the food policy research institute says he foresees “a stronger public relations campaign in the reduction of meat consumption — one like that around cigarettes — emphasizing personal health, compassion for animals, and doing good for the poor and the planet.”

It wouldn’t surprise Professor Eshel if all of this had a real impact. “The good of people’s bodies and the good of the planet are more or less perfectly aligned,” he said.

The United Nations’ Food and Agriculture Organization, in its detailed 2006 study of the impact of meat consumption on the planet, “Livestock’s Long Shadow,” made a similar point: “There are reasons for optimism that the conflicting demands for animal products and environmental services can be reconciled. Both demands are exerted by the same group of people ... the relatively affluent, middle- to high-income class, which is no longer confined to industrialized countries. ... This group of consumers is probably ready to use its growing voice to exert pressure for change and may be willing to absorb the inevitable price increases.”

In fact, Americans are already buying more environmentally friendly products, choosing more sustainably produced meat, eggs and dairy. The number of farmers’ markets has more than doubled in the last 10 years or so, and it has escaped no one’s notice that the organic food market is growing fast. These all represent products that are more expensive but of higher quality.

If those trends continue, meat may become a treat rather than a routine. It won’t be uncommon, but just as surely as the S.U.V. will yield to the hybrid, the half-pound-a-day meat era will end.

Maybe that’s not such a big deal. “Who said people had to eat meat three times a day?” asked Mr. Pollan.

Tapping into the Cancer-Fighter Collective for Treatment

The Cancer Institute of New Jersey is working with others to develop software that lets doctors and researchers compare cases and treatment outcomes

 
TISSUE MICROARRAY (TMA) technique enables investigators to extract small cylinders of tissue from pathology specimens and arrange them in a matrix configuration on a recipient paraffin block such that hundreds can be analyzed simultaneously.

 
IMAGINE: Cancer researchers and IBM scientists are developing a client interface (see here) to provide decision support for characterizing and tracking tumors across consecutive imaging studies.

In an effort to improve cancer care, researchers today announced plans to create a giant database designed to allow oncologists and scientists to share vital information. The Cancer Institute of New Jersey (CINJ) and Rutgers University, both in New Brunswick, along with IBM are developing a computer system that allows physicians and researchers worldwide to tap into the latest developments in cancer research and treatment; they envision it as a tool that will help doctors tailor the best possible therapies for their patients and let scientists track the success—or failure—of previous research.

In particular, the system will feature a digital database of microarrays of cancerous tissue against which new samples can be compared. This will let physicians and researchers study how similar cancers have been treated and which therapies worked best.

Such a database will help doctors determine the best way to proceed once a malignancy has been discovered, says the project's lead investigator, David Foran, director of the Center for Biomedical Imaging & Informatics and professor of pathology and laboratory medicine at U.M.D.N.J–Robert Wood Johnson Medical School in Piscataway, N.J.

Tissue microarrays allow researchers to test slivers of many biopsies at one time. "It's extremely valuable in research and discovery in terms of identifying what proteins come into play at what stage of the disease and what brings about the onset of the disease," Foran says.

The new decision-support system will extend CINJ's Help Defeat Cancer project, launched in July 2006 to develop software and algorithms for improving cancer detection in tissue samples. The initial phase of the project, which has since received a $2.5 million grant from the National Institutes of Health (NIH), netted a large database that allows doctors and researchers to compare various treatment options for patients with breast and colon as well as head and neck cancers.

The developing decision-support software will take the process a step further, allowing physicians and scientists to analyze and classify digitized tissue microarray images of the specimens and contrast them with the more than 100,000 samples already in the system's database. The Ohio State University Medical Center is set to modify the software so it can run on a grid of computers that can be accessed by researchers. CINJ and its partners plan to expand the system to include information about other forms of cancer, although no timetable has been set.

Foran and his colleagues plan to share these technologies with other cancer research facilities around the nation through use of mirrored sites at CINJ and The Ohio State University (O.S.U.), and with the support of the NIH's Cancer Biomedical Informatics Grid program (caBIG). CINJ and O.S.U. will initially use grid technology to provide access to the software and database to cancer researchers at their institutions, plus Arizona State University, and the University of Pennsylvania School of Medicine. Access will be expanded as the project progresses.

During its initial phase, Help Defeat Cancer used computing horsepower from IBM's World Community Grid to create the database of expression patterns that the decision-support system will access. The World Community Grid is a virtual supercomputer that draws its computing resources from unused processing power donated by thousands of volunteers worldwide who make a portion of their PCs available to the grid. IBM established the World Community Grid in November 2004 to deliver computing resources to science and research projects that otherwise would not have the means to advance, says Robin Willner, IBM's vice president of global community initiatives.

In addition to this research project, the grid has hosted eight others mostly in the biomedical field, including those trying to develop treatments for HIV/AIDS, dengue fever and West Nile virus. IBM is donating a high-performance P6 570 Series Class server and a storage system to CINJ to provide an information technology infrastructure that will share the workload of running the new software with computers based at Ohio State.

Geophysicists Urge Steep Cuts in Greenhouse Gas Emissions

The American Geophysical Union says massive reductions in greenhouse gases will be needed—and scientists should speak up about it

earth 
EARTH IN BALANCE: The American Geophysical Union urges reductions of 50 percent or more in greenhouse gas emissions to avoid unpredictable climate change.

The scientists of the American Geophysical Union (AGU) warn that greenhouse gas (GHG) emissions must be slashed in half to keep temperatures from rising 3.6 degrees Fahrenheit (2 degrees Celsius)—or else. "Warming greater than 2 degrees Celsius above 19th-century levels is projected to be disruptive, reducing global agricultural productivity, causing widespread loss of biodiversity and—if sustained over centuries—melting much of the Greenland ice sheet with ensuing rise in sea levels of several meters," the AGU declares in its first statement in four years on "Human Impacts on Climate."

The statement, released today, is the latest—and strongest—statement from the Washington, D.C.–based scientific organization on human-induced climate change. "The record of the Earth's climate since the invention of the thermometer is much better understood now," says physicist Tim Killeen, AGU president and director of the National Center for Atmospheric Research (NCAR) in Boulder, Colo. "This detailed understanding of the climate of the 20th century gives confidence in the ability to project into the future. It is now agreed that we can't explain the detailed temperature record of the 20th century without bringing to bear human effects and GHG emissions. That, in a way, is the smoking gun, the fingerprint."

That fingerprint is now clearly visible on Earth's climate, according to physicist Michael Prather of the University of California, Irvine, who chaired the AGU committee that wrote the statement. Humanity's touch has tipped the scales in favor of more of the sun's heat being trapped by the sky and sea. "Earth's energy system is out [of] balance, excess heat is being pumped into the ocean," Prather says. "That means we're on the move to someplace different."

"Someplace different" will be a lot warmer; 11 of the past 12 years were warmer than any since 1850, and 2007 tied 1998 as the second-warmest since instrument-based records began, according to NASA. Global average sea level has risen by roughly 0.11 inch (3 millimeters) per year since 1993 due to a combination of water expanding as it warms and melting ice sheets. "The scales of change we are seeing is something that modern society has never experienced," Prather notes.

But cutting global (GHG) emissions by 50 percent by 2050 is a major challenge that would require curbs on the smokestacks of power generators and the tailpipes of vehicles as well as a halt to deforestation, among other efforts. Although California, the European Union (E.U.) and others have pledged to meet that goal, global emissions continue to climb rapidly—as do concentrations of GHGs in the atmosphere. "We're on a trajectory upwards for the next five or 10 years no matter what we do. We need to turn that over and bring it down," Prather says. "What we're really looking for is much more substantial cuts by the end of the century."

Regional emission efforts—such as the E.U.'s new plan to reduce emissions by 20 percent by 2030—are already underway. Most rely on so-called cap-and-trade mechanisms: an overall cap on emissions is set, allowances to meet that cap are distributed to polluters, and those who emit more or less than their quota can buy or sell these allowances. Killeen notes that those programs will rely on unprecedented precision in measuring and monitoring greenhouse gas emissions, a role AGU scientists might fill.

But the AGU believes that a broader solution is needed, which is why the statement calls on members to become more involved not only in researching the problem but also spreading the word about the urgency of controlling climate change, something many scientists have been loathe to do in the past, Killeen admits. "Each scientist can do it in their own way," says NCAR senior scientist Bette Otto-Bliesner, also a member of the AGU committee that wrote the statement. "From one-on-one conversations, to giving talks to schools or communities, to going up to Congress."

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