Scientific American - Health

Fewer calories = longer life? A new primate study says, yes

Thu, 09 Jul 2009 15:55:00 EST

Long a subject of debate--and experiments with everything from yeast to mice--the question of whether a lower calorie diet increases life span while decreasing disease has a new smorgasbord of evidence. [More]

Bottled up: Data on contaminants in bottled water still lacking, government says

Thu, 09 Jul 2009 15:20:00 EST

Babies on roller skates, breakdancing and weaving between bottles of water, impart an image of vitality and purity. At least that’s what Evian, a high-end producer of bottled water, would have you believe with its new hit advertisement. As the company’s worldwide director of brand, Michael Aidan, told MSNBC today, “In the majority of countries in recent years, our communication has been very fact-based. But consumers expect more from a big brand: emotion, dream.” [More]

If Swine Flu Weren't Enough, Now There's Swine Ebola

Thu, 09 Jul 2009 14:30:00 EST

Don't worry, it can't hurt you--yet. [More]

Drugmakers Abandon Nature's Pharmacy

Thu, 09 Jul 2009 14:00:00 EST

In the 1992 film Medicine Man, actor Sean Connery stars as a grizzled scientist who discovers a cure for cancer in the Amazon and then struggles to replicate his findings as bulldozers destroy the very forests that harbor it. "What don't you understand?" he wails. "I found the cure for the...plague of the 20th century, and now I've lost it!" [More]

Obama will name Francis Collins as new NIH director

Wed, 08 Jul 2009 18:30:00 EST

Former Human Genome Project leader Francis Collins will be nominated to lead the U.S. National Institutes of Health (NIH). [More]

Are Parasites to Thank for Sex?

Wed, 08 Jul 2009 09:26:08 EST

[The following is an exact transcript of this podcast.]

Sex might seem like one of those little gifts from evolution. But it’s pretty inefficient from an evolutionary perspective. It’d be much easier to reproduce if you could do away with finding the right member of the opposite sex to help you create the next generation. So why did evolution come up with sex?

[More]

Did China's Nuclear Tests Kill Thousands and Doom Future Generations?

Wed, 08 Jul 2009 08:00:00 EST

Enver Tohti remembers the week that it rained dust. That summer of 1973 he was in elementary school in Xinjiang Province, China’s westernmost region, which is inhabited mostly by Uygurs, one of the country’s minority ethnic groups. “There were three days that earth fell from the sky, without wind or any sort of storm. The sky was deadly silent--no sun, no moon,” he recalls. When the kids asked what was happening, the teacher told them that there was a storm on Saturn (its Chinese name translates into “soil planet”). Tohti believed her. It was only years later that he realized it was radioactive dust raised by the test detonation of a nuclear bomb within the province.

Three decades on, Tohti, now a medical doctor, is launching an investigation into the toll still being taken--and one that the Chinese government steadfastly refuses to acknowledge. A few hundred thousand people may have died as a result of radiation from at least 40 nuclear explosions carried out between 1964 and 1996 at the Lop Nur site in Xinjiang, which lies on the Silk Road. Almost 20 million people reside in Xinjiang, and Tohti believes that they offer unique insight into the long-term impact of radiation, including the relatively little studied genetic effects that may be handed down over generations. He is establishing the Lop Nur project at Sapporo Medical University in Japan with physicist Jun Takada to evaluate these consequences.

[More]

Fat mice missing a specific kind of "junk DNA" more likely to be diabetic

Tue, 07 Jul 2009 12:08:00 EST

A large portion of the human genome (approximately 98 percent) does not encode genes. Long thought to be "junk DNA," these portions, researchers continue to learn, can play a role in genetic activity and, subsequently, in health and sickness. According to researchers at the German Institute of Human Nutrition, one such junk fragment might actually prevent symptoms of type 2 diabetes in obese mammals. [More]

Could Animal Surveillance Have Seen Swine Flu Coming?

Tue, 07 Jul 2009 08:00:00 EST

Less than 24 hours after a commercial jet took a sudden detour into the Hudson River this past January, security camera video of the event from multiple vantage points began surfacing. In an age of ubiquitous surveillance, the public has come to assume that someone or something is always watching, ready to spot trouble as it is happening. Yet a novel strain of the influenza A (H1N1) virus jumped species and burst into the human population in March and April, and by late May health and agriculture officials were still trying to figure out where it came from.

The emergence of the new H1N1 flu strain has demonstrated the effectiveness of existing systems to watch for human flu outbreaks while also proving a long-standing theory that pigs could serve as mixing vessels for a pandemic virus. But it has also highlighted how disappointing progress has been in detecting where and how such viruses evolve in animals and in predicting their transmission to people--abilities that might have helped avert a pandemic or at least provide an early warning.

[More]

Government-funded researchers can now study hundreds of embryonic stem cell lines

Tue, 07 Jul 2009 06:00:00 EST

This morning marks a rebirth of a U.S. stem cell research program, now that government-funded researchers can take advantage of many of the 700 stem cell lines that exist around the world. [More]

Bombs bursting in air: What's in those Fourth of July fireworks, anyway?

Fri, 03 Jul 2009 12:00:00 EST

Red, white and blue aside, how green will this weekend’s firework festivities be? Not very, argue some. [More]

How Fructose Impairs the Memory

Fri, 03 Jul 2009 09:00:00 EST

Americans consume more fructose than ever before, yet concerns remain that the sugar, used to sweeten beverages and processed foods, poses health risks. In animals, fructose-rich diets increase the production of fat and promote resistance to the energy-regulating hormone insulin. New research suggests that memory suffers as well, at least in rats.

Neuroscientist Marise B. Parent of Georgia State University and her colleagues fed 11 adolescent rats a diet in which fructose supplied 60 percent of the calories. For 10 other rats, cornstarch took the place of the sweetener. The scientists trained the rats to find a submerged platform in a pool, with the help of surrounding cues.

[More]

MIND Reviews: A Healthy Mind

Fri, 03 Jul 2009 09:00:00 EST

Healthy Mindswww.wliw.org/healthyminds

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For your health, steer clear of the hospital on July Fourth weekend

Fri, 03 Jul 2009 08:30:00 EST

A word to the wise: stay out of the emergency room this long weekend. [More]

Plastic Not-So-Fantastic: How the Versatile Material Harms the Environment and Human Health

Thu, 02 Jul 2009 12:00:00 EST

From cell phones and computers to bicycle helmets and hospital IV bags, plastic has molded society in many ways that make life both easier and safer. But the synthetic material also has left harmful imprints on the environment and perhaps human health, according to a new compilation of articles authored by scientists from around the world.

More than 60 scientists contributed to the new report, which aims to present the first comprehensive review of the impact of plastics on the environment and human health, and offer possible solutions.

[More]

Why haven't we evolved eyes in the backs of our heads?

Thu, 02 Jul 2009 11:00:00 EST

As much as we might appreciate the value of detecting predators that approach from behind--or of keeping an eye on the offspring who follow us--it is important to remember that selection is not directed toward the development or formation of anything, let alone “perfect” organs. In other words, just because some feature seems like a good idea, random mutation and selection will not necessarily fashion it.

Body parts that enable us to detect the sights, sounds, smells, tastes, temperature and tactile elements of our environment did not arise from some master plan or blueprint. Rather selection crafted body parts from available components of cells and tissues within existing forms of life, molding ancient and intermediate versions of sensory cells and organs--each elegant in its own right--like lumps of clay over aeons into the shape and form of our modern bodies. There have never been perfectly formed organs for sight or hearing--just versions that get the job done.

[More]

Do Brain Trainer Games and Software Work?

Thu, 02 Jul 2009 09:00:00 EST

The market for brain-training software continues to grow, but evidence of the programs’ ability to boost memory or intelligence in a broadly applicable way (rather than simply making people better at the task they are practicing) remains scarce. New studies offer a tantalizing suggestion that certain programs may work--but the bulk of the research is murky.

Neuroscientist Peter Snyder of Brown University reviewed nearly 20 software studies and concluded that, as a group, they were underwhelming. They are marred by flaws that induce confounding factors, such as a lack of control groups and follow-up, Snyder warns. More than a third of those he reviewed were too shoddy even to include in the analysis he printed early this year in the journal Alzheimer’s & Dementia. “You’d be surprised at what gets published,” he says. Although some products claimed to treat dementia, Snyder did not find any evidence to back such claims.

[More]

How Do Stress Fractures Develop?

Thu, 02 Jul 2009 08:00:00 EST

Considering the forces involved in many sports, it's no surprise that professional athletes sustain serious injuries to their muscles, ligaments, tendons and bones. A spate of bone fracture–related injuries seems to be dogging professional teams this year. The Houston Rockets of the National Basketball Association lost seven-time all-star Tracy McGrady to season-ending microfracture surgery in February. And on Monday, Rocket’s team physician Tom Clanton announced in the Houston Chronicle that all-star center Yao Ming's fractured foot, which he sustained in a play-off game against the Los Angeles Lakers in May, has worsened over time and may end his career. The possibility that New York Mets centerfielder Carlos Beltran might have a microfractured knee turned fans and fantasy baseball owners into nervous wrecks. Such an injury ended the career of NBA star Jamal Mashburn.

So how do these fractures develop? And why can they have such impact on athletes' careers, in some cases forcing players into early retirement? To find out, we turned to Howard Palamarchuk, a former Olympic-class race walker who is the director of sports medicine at Temple University School of Podiatric Medicine.

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Bald eagles succumb to poison in rat eradication on Alaskan island

Wed, 01 Jul 2009 18:47:00 EST

Last month we reported on bald eagles and other birds found dead after a rat eradication project in Alaska’s Aleutian Islands. The National Wildlife Health Center in Madison, Wis., has confirmed that the birds were casualties of brodifacoum, the poison used in bait scattered around Rat Island by helicopter.

“Every one of the liver samples tested positive for brodifacoum,” U.S. Fish and Wildlife Service spokesman Bruce Woods told Scientific American. Fish and Wildlife law enforcement agents are investigating whether there were any egregious errors and to assess that the poison drop was conducted according to an approved protocol, Woods said.

[More]

DNA Sudoku

Wed, 01 Jul 2009 17:30:00 EST

A 2,000-year-old math theorem, along with Sudoku, may soon help researchers untangle DNA at blazing speeds. [More]