Headline of the day
Groom arrested at own wedding reception (LaCrosse Tribune)
Well, that bodes well.
Feed a monkey a fish and you have fed him for a day. Teach a monkey how to fish ...and you have a fishing monkey.
Scientists find monkeys who know how to fish
By MICHAEL CASEY
BANGKOK, Thailand (AP) - Long-tailed macaque monkeys have a reputation for knowing how to find food - whether it be grabbing fruit from jungle trees or snatching a banana from a startled tourist.
Now, researchers say they have discovered groups of the silver-haired monkeys in Indonesia that fish.
Groups of long-tailed macaques were observed four times over the past eight years scooping up small fish with their hands and eating them along rivers in East Kalimantan and North Sumatra provinces, according to researchers from The Nature Conservancy and the Great Ape Trust.
The species had been known to eat fruit and forage for crabs and insects, but never before fish from rivers.
"It's exciting that after such a long time you see new behavior," said Erik Meijaard, one of the authors of a study on fishing macaques that appeared in last month's International Journal of Primatology. "It's an indication of how little we know about the species."
Meijaard, a senior science adviser at The Nature Conservancy, said it was unclear what prompted the long-tailed macaques to go fishing. But he said it showed a side of the monkeys that is well-known to researchers - an ability to adapt to the changing environment and shifting food sources.
"They are a survivor species, which has the knowledge to cope with difficult conditions," Meijaard said Tuesday. "This behavior potentially symbolizes that ecological flexibility."
The other authors of the paper, which describes the fishing as "rare and isolated" behavior, are The Nature Conservancy volunteers Anne-Marie E. Stewart, Chris H. Gordon and Philippa Schroor, and Serge Wich of the Great Ape Trust.
Some other primates have exhibited fishing behavior, Meijaard wrote, including Japanese macaques, chacma baboons, olive baboons, chimpanzees and orangutans.
Agustin Fuentes, a University of Notre Dame anthropology professor who studies long-tailed macaques, or macaca fascicularis, on the Indonesian island of Bali and in Singapore, said he was "heartened" to see the finding published because such details can offer insight into the "complexity of these animals."
"It was not surprising to me because they are very adaptive," he said. "If you provide them with an opportunity to get something tasty, they will do their best to get it."
Fuentes, who is not connected with the published study, said he has seen similar behavior in Bali, where he has observed long-tailed macaques in flooded paddy fields foraging for frogs and crabs. He said it affirms his belief that their ability to thrive in urban and rural environments from Indonesia to northern Thailand could offer lessons for endangered species.
"We look at so many primate species not doing well. But at the same time, these macaques are doing very well," he said. "We should learn what they do successfully in relation to other species."
Still, Fuentes and Meijaard said further research was needed to understand the full significance of the behavior. Among the lingering questions are what prompted the monkeys to go fishing and how common it is among the species.
Long-tailed macaques were twice observed catching fish by The Nature Conservancy researchers in 2007.
Another little known fact is that the Royal Coachman fly was created by a macaque that lived a quiet life as a fishing guide in a village near Saskatchewan. It’s said the bears swore by him.
Earth must seem like the Jersey Shore when those guys from Nebula 16 come here.
You've got to wonder how they both those heads into the T-shirt that says "The "rents" went to Earth and all I got was this lousy T-shirt."
Star wars: who are we inviting in from the cold?
* Graham Phillips/The Age.com.au
IT SOUNDS wacky, but a fight has broken out among scientists over whether we should be sending messages to aliens. Sure, it's a boffin fight: no vigorous punching, just vigorous publishing, spirited debate, and shock resignations from erudite organisations.
The latest instalment in the scientific scrap is a paper by Russian physicist Alexander Zaitsev. In it he shows why his alien messages can't be held responsible if extraterrestrials do one day invade the Earth. In fact if that happens, he says, blame astronomers.
At the core of the debate is a process called Active SETI. Ordinary SETI - the Search for Extraterrestrial Intelligence - is a worldwide effort by astronomers using radio telescopes to listen for alien signals. Active SETI, which some researchers are now pushing, involves actually sending messages into space.
Zaitsev has been pursuing Active SETI for a decade using a radar facility in the Ukraine. He has sent messages in the direction of various sun-like stars in the Milky Way, hoping to attract alien attention.
But some astronomers believe this puts the Earth at risk. They argue that if we don't send messages, any hostile galactic super-civilisations out there won't know we're here, and we'll remain hidden among the billions of stars. If we do send messages, ET might read our greetings as a dinner invitation.
University of California biologist Jared Diamond has pointed out that there is no guarantee extraterrestrials will be interested in chatting with an inferior species like ours. After all, he says, look what we do to the inferior species on Earth. We shoot them, dissect them, cut off their hands for trophies, exhibit them in cages, inject them with AIDS as a medical experiment, and destroy or take over their habitats.
Now the probability of inducing alien invasion is very low. But because we don't know what is out there, the risk is not zero. New research continually indicates there is reason to expect that alien life in some form is relatively common throughout the universe. Just last month Australian National University researcher Charles Lineweaver added to that research by showing that stars like our sun are very common in the Milky Way. If life got going here, why not around some of those other suns too?
A group of people within the International Academy of Astronautics determines policy decisions on SETI matters, and last year two of its prominent members resigned. They were concerned too many people in the group were professionally interested in sending messages to ET. The two didn't think SETI scientists should be making decisions on behalf of the whole of humanity.
But Zaitsev has hit back at critics. He has calculated that his - and everyone else's - messages to other star systems are small fry compared with the standard exploratory signals astronomers have been sending out for decades. In an attempt to work out the properties of the other planets and orbiting asteroids, astronomers beam microwaves into the solar system. This radiation doesn't stop in our planetary system, however, it keeps going. Aliens could detect it and calculate our location from the signals.
The area of space that has received this radiation is 2000 times bigger than the area targeted with messages, calculates Zaitsev, so the radiation is far more likely to attract attention. Our secret is already out.
Really the only question now is, how much information about ourselves should we beam into the cosmos? So far, those in Active SETI have sent out only simple messages, often just patterns of numbers. The idea is, ET should be able to distinguish the patterns from the general radio noise that clutters the skies and recognise our signals as messages. Also, as the rules of mathematics are universal, aliens should speak the language of maths.
But why not go much further? Seth Shostak, an astronomer at the SETI Institute in California, has suggested we transmit the entire contents of the internet to select stars in the Milky Way. By browsing those billions of websites, ET would not only know there are other intelligences out there, but would be able to learn all about us.
Actually, all that mindless internet detail might just put off the alien hoards from descending on Earth.
Tuesday, June 10, 2008
Monday, June 9, 2008
Making Science More Better For You on 06/09/08
Sure we'll say it..'It's the gift that keeps on giving."
Ah, don't be sore......
Study: 1 in 4 adults in NYC have herpes virus
NEW YORK (AP) - A city Health Department study finds that more than a fourth of adult New Yorkers are infected with the virus that causes genital herpes.
The study, released Monday, says about 26 percent of New York City adults have genital herpes, compared to about 19 percent nationwide.
The department says genital herpes can double a person's risk for contracting HIV.
Herpes can cause painful sores, but most people have no recognizable symptoms.
Among New Yorkers, the herpes rate is higher among women, black people and gay men.
The health department urges consistent use of condoms, and says its STD clinics offer free, confidential herpes testing.
We just called to say that you're late with the payments.
Saudi calls for talks with oil consumers
Jun 9 01:12 PM US/Eastern
Oil kingpin Saudi Arabia called on Monday for talks with consumer nations on soaring world prices and reiterated its readiness to meet any increase in demand.
At a meeting chaired by King Abdullah, the Saudi cabinet restated its view that the leap in prices that saw New York's benchmark contract hit a record 138.54 dollars on Friday was unjustified by fundamentals.
But it added that it had asked Oil Minister Ali al-Nuaimi to "convene a meeting soon of representatives of producer and consumer nations and firms operating in the production, export and trading of oil to discuss the jump in prices, its causes and how to deal with it objectively".
"Saudi Arabia ... has notified all oil companies with which it does business, as well as consumer nations, of its readiness to provide them with any additional quantities of oil they need," added the cabinet statement carried by the official SPA news agency.
It's like having the five families run a clinic for problem gamblers.
Ah, don't be sore......
Study: 1 in 4 adults in NYC have herpes virus
NEW YORK (AP) - A city Health Department study finds that more than a fourth of adult New Yorkers are infected with the virus that causes genital herpes.
The study, released Monday, says about 26 percent of New York City adults have genital herpes, compared to about 19 percent nationwide.
The department says genital herpes can double a person's risk for contracting HIV.
Herpes can cause painful sores, but most people have no recognizable symptoms.
Among New Yorkers, the herpes rate is higher among women, black people and gay men.
The health department urges consistent use of condoms, and says its STD clinics offer free, confidential herpes testing.
We just called to say that you're late with the payments.
Saudi calls for talks with oil consumers
Jun 9 01:12 PM US/Eastern
Oil kingpin Saudi Arabia called on Monday for talks with consumer nations on soaring world prices and reiterated its readiness to meet any increase in demand.
At a meeting chaired by King Abdullah, the Saudi cabinet restated its view that the leap in prices that saw New York's benchmark contract hit a record 138.54 dollars on Friday was unjustified by fundamentals.
But it added that it had asked Oil Minister Ali al-Nuaimi to "convene a meeting soon of representatives of producer and consumer nations and firms operating in the production, export and trading of oil to discuss the jump in prices, its causes and how to deal with it objectively".
"Saudi Arabia ... has notified all oil companies with which it does business, as well as consumer nations, of its readiness to provide them with any additional quantities of oil they need," added the cabinet statement carried by the official SPA news agency.
It's like having the five families run a clinic for problem gamblers.
Tuesday, June 3, 2008
Making Science More Better For You on 06/06/08
Headlines of the day
Kennedy’s Brain Surgeon On Cutting Edge (New York Post)
Does Kobe have Beef with Allen? (SI.com/CNN)
Try saying it out loud.
This just in—Kids do what they want until someone says no. Film at 11.
Kids drinking more sugary drinks and juice
By Anne Harding
Posted 5:06 pm EDT
NEW YORK, Jun. 2, 2008 (Reuters Health) — Children in the U.S. are now getting more of their calories from fruit juice and sugar-sweetened beverages than they were 20 years ago, according to a new analysis of national data published in Pediatrics.
Limiting the consumption of "empty calories" by reducing intake of sugar-sweetened beverages could help kids eat healthier and stay slim, the study's authors, Dr. Y. Claire Wang of the Columbia Mailman School of Public Health in New York City and colleagues, conclude.
However, the authors of another study out today report that children who drink 100 percent fruit juice are no more likely to be overweight than kids who don't. What's more, say Dr. Theresa A. Nicklas of Baylor College of Medicine in Houston and her team, juice drinkers ate more fruit and had a higher intake of several nutrients including vitamin C, folate and potassium.
"The science clearly shows that 100 percent juice is a valuable contributor of nutrients to children's diets and it's not associated with weight," Nicklas told Reuters Health in an interview.
Both sets of researchers looked at the same data: the National Health and Nutrition Examination Survey (NHANES), in which people report what they ate in the previous 24 hours. Wang and her team compared NHANES 1988-1994 and NHANES 1999-2004, while Nicklas and colleagues looked at 1999-2002 NHANES data.
"I don't think we are really saying opposite things," Wang commented. "The focus of our study is to look at the trends."
Wang and her colleagues looked at the percentage of calories consumed as sugar-sweetened beverages and fruit juice from 1988 to 2004. On average, they found, kids 2 to 19 years old got 242 calories a day from these beverages in 1988-1994, and 270 calories daily in 1999-2004; intake of sugar sweetened beverages increased from 204 to 224 calories daily while fruit juice intake rose from 38 to 48 calories per day.
Preschoolers who drank fruit juice consumed an average of 10 ounces a day. However, the American Academy of Pediatrics (AAP) recommends no more than six ounces daily for children one to six years old. Children 7 to 18 years old should drink no more than 12 ounces, or two servings, of fruit juice daily, according to the AAP. Across children of all ages, average fruit juice consumption was 12.4 ounces daily in 1999-2004, up from 11.2 ounces in 1988-1994.
Two- to five-year-olds were consuming 176 calories a day worth of sugar sweetened beverages, equivalent to more than a can of soda, while 6- to 11-year-olds took in 229 calories in sugar-sweetened beverages daily and 12 to 19 year olds consumed 356 calories, about the same as a 20-ounce bottle.
The sharpest increases in sugar-sweetened beverage consumption, of 20 percent, were seen among 6- to 11-year-olds. Consumption also rose more among Latino and African-American children than whites.
Among teens, Wang and her team found, the 84 percent who drank sugar sweetened beverages consumed 30 ounces daily or 360 calories, representing 16 percent of their calorie intake. A 15-year-old boy would have to spend an hour jogging or more than three hours walking in order to burn off this amount of extra calories, the researchers say.
Fruit juice isn't the problem, argues Nicklas, who points out that the daily calorie increase represented by fruit juice is quite small-just 10 calories between the two time periods. "It explains such a small percentage of the calories in the diet. We need to look at where are all the other calories coming from."
Also, Nicklas notes, most Americans aren't meeting fruit consumption requirements, and drinking 100 percent juice may be one way to up fruit intake.
Fruit juices "can never replace the benefits of whole fruit," said Wang. "However I do think that juices do contain some essential nutrients and you cannot say the same thing about sugar sweetened beverages."
Nicklas' study was funded by the US Department of Agriculture and the Juice Products Association. The Robert Wood Johnson Foundation and the Centers for Disease Control and Prevention provided support for Wang's research.
“Limiting the consumption of "empty calories" by reducing intake of sugar-sweetened beverages could help kids eat healthier and stay slim, the study's authors, Dr. Y. Claire Wang of the Columbia Mailman School of Public Health in New York City and colleagues, conclude.” Yeah, sure. Hey look, there’s a flying pig.
Kennedy’s Brain Surgeon On Cutting Edge (New York Post)
Does Kobe have Beef with Allen? (SI.com/CNN)
Try saying it out loud.This just in—Kids do what they want until someone says no. Film at 11.
Kids drinking more sugary drinks and juice
By Anne Harding
Posted 5:06 pm EDT
NEW YORK, Jun. 2, 2008 (Reuters Health) — Children in the U.S. are now getting more of their calories from fruit juice and sugar-sweetened beverages than they were 20 years ago, according to a new analysis of national data published in Pediatrics.
Limiting the consumption of "empty calories" by reducing intake of sugar-sweetened beverages could help kids eat healthier and stay slim, the study's authors, Dr. Y. Claire Wang of the Columbia Mailman School of Public Health in New York City and colleagues, conclude.
However, the authors of another study out today report that children who drink 100 percent fruit juice are no more likely to be overweight than kids who don't. What's more, say Dr. Theresa A. Nicklas of Baylor College of Medicine in Houston and her team, juice drinkers ate more fruit and had a higher intake of several nutrients including vitamin C, folate and potassium.
"The science clearly shows that 100 percent juice is a valuable contributor of nutrients to children's diets and it's not associated with weight," Nicklas told Reuters Health in an interview.
Both sets of researchers looked at the same data: the National Health and Nutrition Examination Survey (NHANES), in which people report what they ate in the previous 24 hours. Wang and her team compared NHANES 1988-1994 and NHANES 1999-2004, while Nicklas and colleagues looked at 1999-2002 NHANES data.
"I don't think we are really saying opposite things," Wang commented. "The focus of our study is to look at the trends."
Wang and her colleagues looked at the percentage of calories consumed as sugar-sweetened beverages and fruit juice from 1988 to 2004. On average, they found, kids 2 to 19 years old got 242 calories a day from these beverages in 1988-1994, and 270 calories daily in 1999-2004; intake of sugar sweetened beverages increased from 204 to 224 calories daily while fruit juice intake rose from 38 to 48 calories per day.
Preschoolers who drank fruit juice consumed an average of 10 ounces a day. However, the American Academy of Pediatrics (AAP) recommends no more than six ounces daily for children one to six years old. Children 7 to 18 years old should drink no more than 12 ounces, or two servings, of fruit juice daily, according to the AAP. Across children of all ages, average fruit juice consumption was 12.4 ounces daily in 1999-2004, up from 11.2 ounces in 1988-1994.
Two- to five-year-olds were consuming 176 calories a day worth of sugar sweetened beverages, equivalent to more than a can of soda, while 6- to 11-year-olds took in 229 calories in sugar-sweetened beverages daily and 12 to 19 year olds consumed 356 calories, about the same as a 20-ounce bottle.
The sharpest increases in sugar-sweetened beverage consumption, of 20 percent, were seen among 6- to 11-year-olds. Consumption also rose more among Latino and African-American children than whites.
Among teens, Wang and her team found, the 84 percent who drank sugar sweetened beverages consumed 30 ounces daily or 360 calories, representing 16 percent of their calorie intake. A 15-year-old boy would have to spend an hour jogging or more than three hours walking in order to burn off this amount of extra calories, the researchers say.
Fruit juice isn't the problem, argues Nicklas, who points out that the daily calorie increase represented by fruit juice is quite small-just 10 calories between the two time periods. "It explains such a small percentage of the calories in the diet. We need to look at where are all the other calories coming from."
Also, Nicklas notes, most Americans aren't meeting fruit consumption requirements, and drinking 100 percent juice may be one way to up fruit intake.
Fruit juices "can never replace the benefits of whole fruit," said Wang. "However I do think that juices do contain some essential nutrients and you cannot say the same thing about sugar sweetened beverages."
Nicklas' study was funded by the US Department of Agriculture and the Juice Products Association. The Robert Wood Johnson Foundation and the Centers for Disease Control and Prevention provided support for Wang's research.
“Limiting the consumption of "empty calories" by reducing intake of sugar-sweetened beverages could help kids eat healthier and stay slim, the study's authors, Dr. Y. Claire Wang of the Columbia Mailman School of Public Health in New York City and colleagues, conclude.” Yeah, sure. Hey look, there’s a flying pig.
Thursday, May 29, 2008
Making Science More Better For You on 05/29/08
Headline of the day
Irked neighbor saws off left half of tree (CNN)
It's nice to know someone still gets "irked."
Must press button. Must get food. Must crap in hand and throw it at strangers.
Monkeys control a robot arm with their thoughts
By Benedict Carey (International Herald Tribune)
Two monkeys with tiny sensors in their brains have learned to control a mechanical arm with just their thoughts, using it to reach for and grab food and even to adjust for the size and stickiness of morsels when necessary, scientists reported on Wednesday.
The report, released online by the journal Nature, is the most striking demonstration to date of brain-machine interface technology. Scientists expect that technology will eventually allow people with spinal cord injuries and other paralyzing conditions to gain more control over their lives.
The findings suggest that brain-controlled prosthetics, while not practical, are at least technically within reach.
In previous studies, researchers showed that humans who had been paralyzed for years could learn to control a cursor on a computer screen with their brain waves and that nonhuman primates could use their thoughts to move a mechanical arm, a robotic hand, a robot on a treadmill or a small vehicle.
The new experiment goes a step further. In it, the monkeys' brains seem to have adopted the mechanical appendage as their own, refining its movement as it interacted with real objects in real time. The monkeys had their own arms gently restrained while they learned to use the added one.
Multimedia
Experts not involved with the study said the findings were likely to accelerate interest in human testing, especially given the need to treat head and spinal injuries in veterans returning from Iraq and Afghanistan.
"This study really pulls together all the pieces from earlier work and provides a clear demonstration of what's possible," said Dr. William Heetderks , director of the extramural science program at the National Institute of Biomedical Imaging and Bioengineering.
Dr. John Donoghue, director of the Institute of Brain Science at Brown University, said the new report was "important because it's the most comprehensive study showing how an animal interacts with complex objects, using only brain activity."
The researchers, from the University of Pittsburgh and Carnegie Mellon University, used monkeys partly because of their anatomical similarities to humans and partly because they are quick learners.
In the experiment, two macaques first used a joystick to gain a feel for the arm, which had shoulder joints, an elbow and a grasping claw with two mechanical fingers.
Then, just beneath the monkeys' skulls, the scientists implanted a grid about the size of a large freckle. It sat on the motor cortex, over a patch of cells known to signal arm and hand movements. The grid held 100 tiny electrodes, each connecting to a single neuron, its wires running out of the brain and to a computer.
The computer was programmed to analyze the collective firing of these 100 motor neurons, translate that sum into an electronic command and send it instantaneously to the arm, which was mounted flush with the left shoulder.
The scientists used the computer to help the monkeys move the arm at first, essentially teaching them with biofeedback.
After several days, the monkeys needed no help. They sat stationary in a chair, repeatedly manipulating the arm with their brain to reach out and grab grapes, marshmallows and other nuggets dangled in front of them. The snacks reached the mouths about two-thirds of the time — an impressive rate, compared with earlier work.
The monkeys learned to hold the grip open on approaching the food, close it just enough to hold the food and gradually loosen the grip when feeding.
On several occasions, a monkey kept its claw open on the way back, with the food stuck to one finger. At other times, a monkey moved the arm to lick the fingers clean or to push a bit of food into its mouth while ignoring a newly presented morsel.
The animals were apparently freelancing, discovering new uses for the arm, showing "displays of embodiment that would never be seen in a virtual environment," the researchers wrote.
"In the real world, things don't work as expected," said the senior author of the paper, Dr. Andrew Schwartz, a professor of neurobiology at the University of Pittsburgh. "The marshmallow sticks to your hand or the food slips, and you can't program a computer to anticipate all of that.
"But the monkeys' brains adjusted. They were licking the marshmallow off the prosthetic gripper, pushing food into their mouth, as if it were their own hand."
The co-authors were Meel Velliste, Sagi Perel, M. Chance Spalding and Andrew Whitford.
Scientists have to clear several hurdles before this technology becomes practical, experts said. Implantable electrode grids do not generally last more than a period of months, for reasons that remain unclear.
The equipment to read and transmit the signal can be cumbersome and in need of continual monitoring and recalibrating. And no one has yet demonstrated a workable wireless system that would eliminate the need for connections through the scalp.
Yet Schwartz's team, Donoghue's group and others are working on all of the problems, and the two macaques' rapid learning curve in taking ownership of a foreign limb gives scientists confidence that the main obstacles are technical and, thus, negotiable.
In an editorial accompanying the Nature study, Dr. John Kalaska, a neuroscientist at the University of Montreal, argued that after such bugs had been worked out, scientists might even discover areas of the cortex that allow more intimate, subtle control of prosthetic devices.
Such systems, Kalaska wrote, "would allow patients with severe motor deficits to interact and communicate with the world not only by the moment-to-moment control of the motion of robotic devices, but also in a more natural and intuitive manner that reflects their overall goals, needs and preferences."
They knew it was Viking DNA because it wore a tiny hat with little horns on it and kept asking for lutefisk.
Authentic Viking DNA Retrieved From 1,000-year-old Skeletons
ScienceDaily (May 28, 2008) — Although "Viking" literally means "pirate," recent research has indicated that the Vikings were also traders to the fishmongers of Europe. Stereotypically, these Norsemen are usually pictured wearing a horned helmet but in a new study, Jørgen Dissing and colleagues from the University of Copenhagen, investigated what went under the helmet; the scientists were able to extract authentic DNA from ancient Viking skeletons, avoiding many of the problems of contamination faced by past researchers.
Analysis of DNA from the remains of ancient humans provides valuable insights into such important questions as the origin of genetic diseases, migration patterns of our forefathers and tribal and family patterns.
Unfortunately, severe problems connected with the retrieval and analysis of DNA from ancient organisms (like the scarcity of intact molecules) are further aggravated in the case of ancient humans. This is because of the great risk of contamination with abundant DNA from modern humans. Humans, then, are involved at all steps, from excavation to laboratory analyses. This means that many previous results have subsequently been disputed as attributed to the presence of contaminant DNA, and some researchers even claim that it is impossible to obtain reliable results with ancient human DNA.
Using freshly sampled material from ten Viking skeletons from around AD 1,000, from a non-Christian burial site on the Danish island of Funen, Dissing and colleagues showed that it is indeed possible to retrieve authentic DNA from ancient humans.
Wearing protective suits, the researchers removed the teeth from the jaw at the moment the skeletons were unearthed when they had been untouched for 1,000 years. The subsequent laboratory procedures were also carefully controlled in order to avoid contamination.
Analysis of the Viking DNA showed no evidence of contamination with extraneous DNA, and typing of the endogenous DNA gave reproducible results and showed that these individuals were just as diverse as contemporary humans. A reliable retrieval of authentic DNA opens the way for a valuable use of prehistoric human remains to illuminate the genetic history of past and extant populations.
Irked neighbor saws off left half of tree (CNN)
It's nice to know someone still gets "irked."
Must press button. Must get food. Must crap in hand and throw it at strangers.
Monkeys control a robot arm with their thoughts
By Benedict Carey (International Herald Tribune)
Two monkeys with tiny sensors in their brains have learned to control a mechanical arm with just their thoughts, using it to reach for and grab food and even to adjust for the size and stickiness of morsels when necessary, scientists reported on Wednesday.
The report, released online by the journal Nature, is the most striking demonstration to date of brain-machine interface technology. Scientists expect that technology will eventually allow people with spinal cord injuries and other paralyzing conditions to gain more control over their lives.
The findings suggest that brain-controlled prosthetics, while not practical, are at least technically within reach.
In previous studies, researchers showed that humans who had been paralyzed for years could learn to control a cursor on a computer screen with their brain waves and that nonhuman primates could use their thoughts to move a mechanical arm, a robotic hand, a robot on a treadmill or a small vehicle.
The new experiment goes a step further. In it, the monkeys' brains seem to have adopted the mechanical appendage as their own, refining its movement as it interacted with real objects in real time. The monkeys had their own arms gently restrained while they learned to use the added one.
Multimedia
Experts not involved with the study said the findings were likely to accelerate interest in human testing, especially given the need to treat head and spinal injuries in veterans returning from Iraq and Afghanistan.
"This study really pulls together all the pieces from earlier work and provides a clear demonstration of what's possible," said Dr. William Heetderks , director of the extramural science program at the National Institute of Biomedical Imaging and Bioengineering.
Dr. John Donoghue, director of the Institute of Brain Science at Brown University, said the new report was "important because it's the most comprehensive study showing how an animal interacts with complex objects, using only brain activity."
The researchers, from the University of Pittsburgh and Carnegie Mellon University, used monkeys partly because of their anatomical similarities to humans and partly because they are quick learners.
In the experiment, two macaques first used a joystick to gain a feel for the arm, which had shoulder joints, an elbow and a grasping claw with two mechanical fingers.
Then, just beneath the monkeys' skulls, the scientists implanted a grid about the size of a large freckle. It sat on the motor cortex, over a patch of cells known to signal arm and hand movements. The grid held 100 tiny electrodes, each connecting to a single neuron, its wires running out of the brain and to a computer.
The computer was programmed to analyze the collective firing of these 100 motor neurons, translate that sum into an electronic command and send it instantaneously to the arm, which was mounted flush with the left shoulder.
The scientists used the computer to help the monkeys move the arm at first, essentially teaching them with biofeedback.
After several days, the monkeys needed no help. They sat stationary in a chair, repeatedly manipulating the arm with their brain to reach out and grab grapes, marshmallows and other nuggets dangled in front of them. The snacks reached the mouths about two-thirds of the time — an impressive rate, compared with earlier work.
The monkeys learned to hold the grip open on approaching the food, close it just enough to hold the food and gradually loosen the grip when feeding.
On several occasions, a monkey kept its claw open on the way back, with the food stuck to one finger. At other times, a monkey moved the arm to lick the fingers clean or to push a bit of food into its mouth while ignoring a newly presented morsel.
The animals were apparently freelancing, discovering new uses for the arm, showing "displays of embodiment that would never be seen in a virtual environment," the researchers wrote.
"In the real world, things don't work as expected," said the senior author of the paper, Dr. Andrew Schwartz, a professor of neurobiology at the University of Pittsburgh. "The marshmallow sticks to your hand or the food slips, and you can't program a computer to anticipate all of that.
"But the monkeys' brains adjusted. They were licking the marshmallow off the prosthetic gripper, pushing food into their mouth, as if it were their own hand."
The co-authors were Meel Velliste, Sagi Perel, M. Chance Spalding and Andrew Whitford.
Scientists have to clear several hurdles before this technology becomes practical, experts said. Implantable electrode grids do not generally last more than a period of months, for reasons that remain unclear.
The equipment to read and transmit the signal can be cumbersome and in need of continual monitoring and recalibrating. And no one has yet demonstrated a workable wireless system that would eliminate the need for connections through the scalp.
Yet Schwartz's team, Donoghue's group and others are working on all of the problems, and the two macaques' rapid learning curve in taking ownership of a foreign limb gives scientists confidence that the main obstacles are technical and, thus, negotiable.
In an editorial accompanying the Nature study, Dr. John Kalaska, a neuroscientist at the University of Montreal, argued that after such bugs had been worked out, scientists might even discover areas of the cortex that allow more intimate, subtle control of prosthetic devices.
Such systems, Kalaska wrote, "would allow patients with severe motor deficits to interact and communicate with the world not only by the moment-to-moment control of the motion of robotic devices, but also in a more natural and intuitive manner that reflects their overall goals, needs and preferences."
They knew it was Viking DNA because it wore a tiny hat with little horns on it and kept asking for lutefisk.
Authentic Viking DNA Retrieved From 1,000-year-old Skeletons
ScienceDaily (May 28, 2008) — Although "Viking" literally means "pirate," recent research has indicated that the Vikings were also traders to the fishmongers of Europe. Stereotypically, these Norsemen are usually pictured wearing a horned helmet but in a new study, Jørgen Dissing and colleagues from the University of Copenhagen, investigated what went under the helmet; the scientists were able to extract authentic DNA from ancient Viking skeletons, avoiding many of the problems of contamination faced by past researchers.
Analysis of DNA from the remains of ancient humans provides valuable insights into such important questions as the origin of genetic diseases, migration patterns of our forefathers and tribal and family patterns.
Unfortunately, severe problems connected with the retrieval and analysis of DNA from ancient organisms (like the scarcity of intact molecules) are further aggravated in the case of ancient humans. This is because of the great risk of contamination with abundant DNA from modern humans. Humans, then, are involved at all steps, from excavation to laboratory analyses. This means that many previous results have subsequently been disputed as attributed to the presence of contaminant DNA, and some researchers even claim that it is impossible to obtain reliable results with ancient human DNA.
Using freshly sampled material from ten Viking skeletons from around AD 1,000, from a non-Christian burial site on the Danish island of Funen, Dissing and colleagues showed that it is indeed possible to retrieve authentic DNA from ancient humans.
Wearing protective suits, the researchers removed the teeth from the jaw at the moment the skeletons were unearthed when they had been untouched for 1,000 years. The subsequent laboratory procedures were also carefully controlled in order to avoid contamination.
Analysis of the Viking DNA showed no evidence of contamination with extraneous DNA, and typing of the endogenous DNA gave reproducible results and showed that these individuals were just as diverse as contemporary humans. A reliable retrieval of authentic DNA opens the way for a valuable use of prehistoric human remains to illuminate the genetic history of past and extant populations.
Wednesday, May 28, 2008
Making Science More Better For You on 05/28/08
Headlines of the day
Nude Maid Stole Wife's Jewelry, Husband Says (tampabay.com)
Car carrying nude couple runs off road, hits sign PalmBeachPost.com
Hey Florida, put some clothes on.
Yo T-Rex, I’m Walkin’ Here
Giant Flying Reptiles Preferred To Walk
ScienceDaily (May 28, 2008) —New research into gigantic flying reptiles has found that they weren't all gull-like predators grabbing fish from the water but that some were strongly adapted for life on the ground.
Pterosaurs lived during the age of dinosaurs 230 to 65 million years ago. A new study by researchers at the University of Portsmouth on one particular type of pterosaur, the azhdarchids, claims they were more likely to stalk animals on foot than to fly.
Until now virtually all pterosaurs have been imagined by palaeontologists to have lived like modern seabirds: as gull- or pelican-like predators that flew over lakes and oceans, grabbing fish from the water. But a study of azhdarchid anatomy, footprints and the distribution of their fossils by Mark Witton and Dr Darren Naish shows that this stereotype does not apply to all flying reptiles and some were strongly adapted for terrestrial life.
Azhdarchids were probably better than any other ptersosaurs at walking because they had long limbs and skulls well suited for picking up small animals and other food from the ground.
Azhdarchids, named after the Uzbek word for 'dragon', were gigantic toothless pterosaurs. Azhdarchids include the largest of all pterosaurs: some had wingspans exceeding 10 metres and the biggest ones were as tall as a giraffe.
Dr Naish said: "Azhdarchids first became reasonably well known in the 1970s but how they lived has been the subject of much debate. Originally described as vulture-like scavengers, they were later suggested to be mud-probers (sticking their long bills into the ground in search of prey), and later still suggested to make a living by flying over the water's surface, grabbing fish.
"Other lifestyles have been suggested too. These lifestyles all seem radically divergent so Mark and I sat down and carefully examined the evidence and we argue that azhdarchids were specialised terrestrial stalkers. All the details of their anatomy, and the environment their fossils are found in, show that they made their living by walking around, reaching down to grab and pick up animals and other prey."
Animals like azhdarchids no longer exist but the closest analogues in the modern world are large ground-feeding birds like ground-hornbills and storks.
The researchers studied fossils in London, Portsmouth and Germany and compared the anatomy of azhdarchid with those of modern animals. This showed that azhdarchids were strikingly different from mud-probers and animals that grab prey from the water's surface while in flight.
Dr Naish said: "We also worked out the range of motion possible in the azhdarchid neck: this bizarrely stiff neck has previously been a problem for other ideas about azhdarchid lifestyle, but it fits with our model as all a terrestrial stalker needs to do its raise and lower its bill tip to the ground."
Other aspects of azhdarchid anatomy, such as their relatively small padded feet and long but weak jaws often pose problems in other proposed lifestyles but fit perfectly with the terrestrial stalker hypothesis. Mr Witton said: "The small feet of azhdarchids were no good for wading around lake margins or swimming should they land on water but are excellent for strutting around on land. As for what azhdarchids would eat, they'd have snapped up bite-size animals or even bits of fruit. But if your skull is over two metres in length then bite-size includes everything up to a dinosaur the size of a fox."
The researchers found that over 50 percent of azhdarchid fossils come from sediments that were laid down inland. Significantly, the only articulated azhdarchid fossils we have come from these inland sediments.
“Pterosaurs lived during the age of dinosaurs 230 to 65 million years ago.:
Yeah, well that certainly narrows it down.
Risky Behavior among Teens—we’re shocked
Energy drinks linked to risky behavior among teenagers
By Tara Parker-Pope/International Heral Tribune
Published: May 27, 2008
Health researchers have identified a surprising new predictor for risky behavior among teenagers and young adults: the energy drink.
Super-caffeinated energy drinks, with names like Red Bull, Monster, Full Throttle and Amp, have surged in popularity in the past decade. About a third of 12- to 24-year-olds say they regularly down energy drinks, which account for more than $3 billion in annual sales in the United States.
The trend has been the source of growing concern among health researchers and school officials. Around the country, the drinks have been linked with reports of nausea, abnormal heart rhythms and emergency room visits.
In Colorado Springs, several high school students last year became ill after drinking Spike Shooter, a high caffeine drink, prompting the principal to ban the beverages. In March, four middle school students in Broward County, Florida, went to the emergency room with heart palpitations and sweating after drinking the energy beverage Redline. In Tigard, Oregon, teachers this month sent parents e-mail alerting them that students who brought energy drinks to school were "literally drunk on a caffeine buzz or falling off a caffeine crash."
New research suggests the drinks are associated with a health issue far more worrisome than the jittery effects of caffeine — risk taking.
In March, The Journal of American College Health published a report on the link between energy drinks, athletics and risky behavior. The study's author, Kathleen Miller, an addiction researcher at the University of Buffalo, says it suggests that high consumption of energy drinks is associated with "toxic jock" behavior, a constellation of risky and aggressive behaviors including unprotected sex, substance abuse and violence.
The finding doesn't mean the drinks cause bad behavior. But the data suggest that regular consumption of energy drinks may be a red flag for parents that their children are more likely to take risks with their health and safety. "It appears the kids who are heavily into drinking energy drinks are more likely to be the ones who are inclined toward taking risks," Miller said.
The American Beverage Association says its members don't market energy drinks to teenagers. "The intended audience is adults," said Craig Stevens, a spokesman. He says the marketing is meant for "people who can actually afford the two or three bucks to buy the products."
The drinks include a variety of ingredients in different combinations: plant-based stimulants like guarana, herbs like ginkgo and ginseng, sugar, amino acids including taurine as well as vitamins. But the main active ingredient is caffeine.
Caffeine content varies. A 12-ounce serving of Amp contains 107 milligrams of caffeine, compared with 34 to 38 milligrams for the same amount of Coca-Cola or Pepsi. Monster has 120 milligrams and Red Bull has 116. Higher on the spectrum, Spike Shooter contains 428 milligrams of caffeine in 12 ounces, and Wired X344 contains 258.
Stevens points out that "mainstream" energy drinks often have less caffeine than a cup of coffee. At Starbucks, the caffeine content varies depending on the drink, from 75 milligrams in a 12-ounce cappuccino or latte to as much as 250 milligrams in a 12-ounce brewed coffee.
One concern about the drinks is that because they are served cold, they may be consumed in larger amounts and more quickly than hot coffee drinks, which are sipped. Another worry is the increasing popularity of mixing energy drinks with alcohol. The addition of caffeine can make alcohol users feel less drunk, but motor coordination and visual reaction time are just as impaired as when they drink alcohol by itself, according to an April 2006 study in the medical journal Alcoholism: Clinical and Experimental Research.
"You're every bit as drunk, you're just an awake drunk," said Mary Claire O'Brien, associate professor in the departments of emergency medicine and public health services at Wake Forest University Baptist Medical Center in Winston-Salem, North Carolina
O'Brien surveyed energy drink and alcohol use among college students at 10 universities in North Carolina. The study, published this month in Academic Emergency Medicine, showed that students who mixed energy drinks with alcohol got drunk twice as often as those who consumed alcohol by itself and were far more likely to be injured or require medical treatment while drinking. Energy drink mixers were more likely to be victims or perpetrators of aggressive sexual behavior. The effect remained even after researchers controlled for the amount of alcohol consumed.
Energy drink marketers say they don't encourage consumers to mix the drinks with alcohol. Michelle Naughton, a spokeswoman for PepsiCo, which markets Amp, said, "We expect consumers to enjoy our products responsibly."
That’s odd, we thought the energy drinks were part of the risky behavior. You know, sort of like product placement for adolescents.
Nude Maid Stole Wife's Jewelry, Husband Says (tampabay.com)
Car carrying nude couple runs off road, hits sign PalmBeachPost.com
Hey Florida, put some clothes on.
Yo T-Rex, I’m Walkin’ Here
Giant Flying Reptiles Preferred To Walk
ScienceDaily (May 28, 2008) —New research into gigantic flying reptiles has found that they weren't all gull-like predators grabbing fish from the water but that some were strongly adapted for life on the ground.
Pterosaurs lived during the age of dinosaurs 230 to 65 million years ago. A new study by researchers at the University of Portsmouth on one particular type of pterosaur, the azhdarchids, claims they were more likely to stalk animals on foot than to fly.
Until now virtually all pterosaurs have been imagined by palaeontologists to have lived like modern seabirds: as gull- or pelican-like predators that flew over lakes and oceans, grabbing fish from the water. But a study of azhdarchid anatomy, footprints and the distribution of their fossils by Mark Witton and Dr Darren Naish shows that this stereotype does not apply to all flying reptiles and some were strongly adapted for terrestrial life.
Azhdarchids were probably better than any other ptersosaurs at walking because they had long limbs and skulls well suited for picking up small animals and other food from the ground.
Azhdarchids, named after the Uzbek word for 'dragon', were gigantic toothless pterosaurs. Azhdarchids include the largest of all pterosaurs: some had wingspans exceeding 10 metres and the biggest ones were as tall as a giraffe.
Dr Naish said: "Azhdarchids first became reasonably well known in the 1970s but how they lived has been the subject of much debate. Originally described as vulture-like scavengers, they were later suggested to be mud-probers (sticking their long bills into the ground in search of prey), and later still suggested to make a living by flying over the water's surface, grabbing fish.
"Other lifestyles have been suggested too. These lifestyles all seem radically divergent so Mark and I sat down and carefully examined the evidence and we argue that azhdarchids were specialised terrestrial stalkers. All the details of their anatomy, and the environment their fossils are found in, show that they made their living by walking around, reaching down to grab and pick up animals and other prey."
Animals like azhdarchids no longer exist but the closest analogues in the modern world are large ground-feeding birds like ground-hornbills and storks.
The researchers studied fossils in London, Portsmouth and Germany and compared the anatomy of azhdarchid with those of modern animals. This showed that azhdarchids were strikingly different from mud-probers and animals that grab prey from the water's surface while in flight.
Dr Naish said: "We also worked out the range of motion possible in the azhdarchid neck: this bizarrely stiff neck has previously been a problem for other ideas about azhdarchid lifestyle, but it fits with our model as all a terrestrial stalker needs to do its raise and lower its bill tip to the ground."
Other aspects of azhdarchid anatomy, such as their relatively small padded feet and long but weak jaws often pose problems in other proposed lifestyles but fit perfectly with the terrestrial stalker hypothesis. Mr Witton said: "The small feet of azhdarchids were no good for wading around lake margins or swimming should they land on water but are excellent for strutting around on land. As for what azhdarchids would eat, they'd have snapped up bite-size animals or even bits of fruit. But if your skull is over two metres in length then bite-size includes everything up to a dinosaur the size of a fox."
The researchers found that over 50 percent of azhdarchid fossils come from sediments that were laid down inland. Significantly, the only articulated azhdarchid fossils we have come from these inland sediments.
“Pterosaurs lived during the age of dinosaurs 230 to 65 million years ago.:
Yeah, well that certainly narrows it down.
Risky Behavior among Teens—we’re shocked
Energy drinks linked to risky behavior among teenagers
By Tara Parker-Pope/International Heral Tribune
Published: May 27, 2008
Health researchers have identified a surprising new predictor for risky behavior among teenagers and young adults: the energy drink.
Super-caffeinated energy drinks, with names like Red Bull, Monster, Full Throttle and Amp, have surged in popularity in the past decade. About a third of 12- to 24-year-olds say they regularly down energy drinks, which account for more than $3 billion in annual sales in the United States.
The trend has been the source of growing concern among health researchers and school officials. Around the country, the drinks have been linked with reports of nausea, abnormal heart rhythms and emergency room visits.
In Colorado Springs, several high school students last year became ill after drinking Spike Shooter, a high caffeine drink, prompting the principal to ban the beverages. In March, four middle school students in Broward County, Florida, went to the emergency room with heart palpitations and sweating after drinking the energy beverage Redline. In Tigard, Oregon, teachers this month sent parents e-mail alerting them that students who brought energy drinks to school were "literally drunk on a caffeine buzz or falling off a caffeine crash."
New research suggests the drinks are associated with a health issue far more worrisome than the jittery effects of caffeine — risk taking.
In March, The Journal of American College Health published a report on the link between energy drinks, athletics and risky behavior. The study's author, Kathleen Miller, an addiction researcher at the University of Buffalo, says it suggests that high consumption of energy drinks is associated with "toxic jock" behavior, a constellation of risky and aggressive behaviors including unprotected sex, substance abuse and violence.
The finding doesn't mean the drinks cause bad behavior. But the data suggest that regular consumption of energy drinks may be a red flag for parents that their children are more likely to take risks with their health and safety. "It appears the kids who are heavily into drinking energy drinks are more likely to be the ones who are inclined toward taking risks," Miller said.
The American Beverage Association says its members don't market energy drinks to teenagers. "The intended audience is adults," said Craig Stevens, a spokesman. He says the marketing is meant for "people who can actually afford the two or three bucks to buy the products."
The drinks include a variety of ingredients in different combinations: plant-based stimulants like guarana, herbs like ginkgo and ginseng, sugar, amino acids including taurine as well as vitamins. But the main active ingredient is caffeine.
Caffeine content varies. A 12-ounce serving of Amp contains 107 milligrams of caffeine, compared with 34 to 38 milligrams for the same amount of Coca-Cola or Pepsi. Monster has 120 milligrams and Red Bull has 116. Higher on the spectrum, Spike Shooter contains 428 milligrams of caffeine in 12 ounces, and Wired X344 contains 258.
Stevens points out that "mainstream" energy drinks often have less caffeine than a cup of coffee. At Starbucks, the caffeine content varies depending on the drink, from 75 milligrams in a 12-ounce cappuccino or latte to as much as 250 milligrams in a 12-ounce brewed coffee.
One concern about the drinks is that because they are served cold, they may be consumed in larger amounts and more quickly than hot coffee drinks, which are sipped. Another worry is the increasing popularity of mixing energy drinks with alcohol. The addition of caffeine can make alcohol users feel less drunk, but motor coordination and visual reaction time are just as impaired as when they drink alcohol by itself, according to an April 2006 study in the medical journal Alcoholism: Clinical and Experimental Research.
"You're every bit as drunk, you're just an awake drunk," said Mary Claire O'Brien, associate professor in the departments of emergency medicine and public health services at Wake Forest University Baptist Medical Center in Winston-Salem, North Carolina
O'Brien surveyed energy drink and alcohol use among college students at 10 universities in North Carolina. The study, published this month in Academic Emergency Medicine, showed that students who mixed energy drinks with alcohol got drunk twice as often as those who consumed alcohol by itself and were far more likely to be injured or require medical treatment while drinking. Energy drink mixers were more likely to be victims or perpetrators of aggressive sexual behavior. The effect remained even after researchers controlled for the amount of alcohol consumed.
Energy drink marketers say they don't encourage consumers to mix the drinks with alcohol. Michelle Naughton, a spokeswoman for PepsiCo, which markets Amp, said, "We expect consumers to enjoy our products responsibly."
That’s odd, we thought the energy drinks were part of the risky behavior. You know, sort of like product placement for adolescents.
Friday, May 23, 2008
Making Science More Better For You on 05/23/08
We’re kind of surprised that the structure of the receptor was a mystery. It’s located right next to the pork and cold beer receptors.
Some Like It Hot! Structure Of Receptor For Hot Chili Pepper And Pain Revealed
ScienceDaily (May 22, 2008) — You can now not only feel the spicy kick of a jalapeno pepper, you can also see it in full 3D, thanks to researchers at Baylor College of Medicine in Houston.
Using sophisticated equipment, the research team led by Dr Theodore G. Wensel, professor of biochemistry and molecular biology at BCM, generated the first three dimensional view of the protein that allows you to sense the heat of a hot pepper.
"This protein, known as TRPV1, not only senses spicy foods, but also makes it possible to feel real heat and the pain and inflammation related to other medical conditions," said Wensel, senior author on the study. "This method of viewing the protein now gives us the chance to clearly see the functional relationship between outside stimuli and the nerve cell."
The outside stimulus used in this study was the heat of a chili pepper. It has been known for years that the burning sensation results from the action of a chemical known as capsaicin on TRPV1 found on the nerve cell membrane. TRPV1 is an ion channel, a tiny pore on the cell membrane that allows chemicals such as calcium to flux in and out.
"Any time you feel a burn or pain sensation, it is mediated by a TRPV1 channel. Different levels of heat are mediated by different TRP channels," said Dr. Vera Moiseenkova-Bell, a postdoctoral associate in Wensel's laboratory at BCM and first author of the study. "They are all related but each is regulated in a different manner."
Wensel said the three-dimensional image of TRPV1 revealed surprising information about its structure. It is made up of a pore domain embedded in the cell membrane, and a "hanging basket" of regulatory domains that extend into the interior of the cell.
"It's an unusual thing. There is a whole hollow 'basket' area but we don't know what's that's for," Wensel said. "Now the search is on to understand how the 'basket' area regulates the channel."
Isolating TRPV1 gives researchers an idea of how other channels are structured as well.
"Visualization of TRPV1 gives us insight on other TRP channels since they are structurally similar," said Moiseenkova-Bell. "Pharmaceutical companies target these TRP channels to make sure the drug binds properly. With this first structure we can start to build models of binding sites and hopefully in the future design more effective pharmaceuticals for a wide range of medical conditions."
Studying these channels is nothing new. In the past, scientists could measure the activity in the cells but it was unclear what each channel was responding to. Determining which proteins interacted with TRPV1, however, required Wensel's lab to create a purified model.
The protein had to be removed from cells, purified, and reconstituted in a synthetic membrane so researchers could control channel activity.
"Since calcium is involved in cell signaling, following the calcium movement confirmed the protein is active," said Wensel. "We are the first group to purify a TRPV1 channel and control what goes in and out when the channel opens."
The report appears in the current issue of the Proceedings of the National Academy of Sciences.
Others who took part in this work are Dr. Lia Stanicu, of Purdue University, Dr. Irina Serysheva, adjunct associate professor of biochemistry at BCM, and BCM graduate student, Ben J. Tobe.
Funding for this work came from the National Institutes of Health.
Some Like It Hot! Structure Of Receptor For Hot Chili Pepper And Pain Revealed
ScienceDaily (May 22, 2008) — You can now not only feel the spicy kick of a jalapeno pepper, you can also see it in full 3D, thanks to researchers at Baylor College of Medicine in Houston.
Using sophisticated equipment, the research team led by Dr Theodore G. Wensel, professor of biochemistry and molecular biology at BCM, generated the first three dimensional view of the protein that allows you to sense the heat of a hot pepper.
"This protein, known as TRPV1, not only senses spicy foods, but also makes it possible to feel real heat and the pain and inflammation related to other medical conditions," said Wensel, senior author on the study. "This method of viewing the protein now gives us the chance to clearly see the functional relationship between outside stimuli and the nerve cell."
The outside stimulus used in this study was the heat of a chili pepper. It has been known for years that the burning sensation results from the action of a chemical known as capsaicin on TRPV1 found on the nerve cell membrane. TRPV1 is an ion channel, a tiny pore on the cell membrane that allows chemicals such as calcium to flux in and out.
"Any time you feel a burn or pain sensation, it is mediated by a TRPV1 channel. Different levels of heat are mediated by different TRP channels," said Dr. Vera Moiseenkova-Bell, a postdoctoral associate in Wensel's laboratory at BCM and first author of the study. "They are all related but each is regulated in a different manner."
Wensel said the three-dimensional image of TRPV1 revealed surprising information about its structure. It is made up of a pore domain embedded in the cell membrane, and a "hanging basket" of regulatory domains that extend into the interior of the cell.
"It's an unusual thing. There is a whole hollow 'basket' area but we don't know what's that's for," Wensel said. "Now the search is on to understand how the 'basket' area regulates the channel."
Isolating TRPV1 gives researchers an idea of how other channels are structured as well.
"Visualization of TRPV1 gives us insight on other TRP channels since they are structurally similar," said Moiseenkova-Bell. "Pharmaceutical companies target these TRP channels to make sure the drug binds properly. With this first structure we can start to build models of binding sites and hopefully in the future design more effective pharmaceuticals for a wide range of medical conditions."
Studying these channels is nothing new. In the past, scientists could measure the activity in the cells but it was unclear what each channel was responding to. Determining which proteins interacted with TRPV1, however, required Wensel's lab to create a purified model.
The protein had to be removed from cells, purified, and reconstituted in a synthetic membrane so researchers could control channel activity.
"Since calcium is involved in cell signaling, following the calcium movement confirmed the protein is active," said Wensel. "We are the first group to purify a TRPV1 channel and control what goes in and out when the channel opens."
The report appears in the current issue of the Proceedings of the National Academy of Sciences.
Others who took part in this work are Dr. Lia Stanicu, of Purdue University, Dr. Irina Serysheva, adjunct associate professor of biochemistry at BCM, and BCM graduate student, Ben J. Tobe.
Funding for this work came from the National Institutes of Health.
Thursday, May 22, 2008
Making Science More Better For You on 05/22/08
Headline of the day
European Court agrees to hear chimp's plea for human rights
(This Is London.co.uk)
If they can’t have him declared “a person,” maybe they can have him recognized as a European.
European Court agrees to hear chimp's plea for human rights
(This Is London.co.uk)
If they can’t have him declared “a person,” maybe they can have him recognized as a European.
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