Drug Blocks Cocaine's Effects

Similar to Parkinson's treatment, could provide a basis for new abuse therapies
Betterhumans Staff
2/22/2005 4:13 PM


A substance similar to a Parkinson's disease treatment blocks the stimulating effects of cocaine and could provide the basis for drugs that counter cocaine abuse.

Researchers are seeking a molecule that blocks cocaine's effects in a specific way, disabling its ability to stimulate and addict without disabling brain mechanisms it targets.

Jonathan Katz and colleagues at the US National Institute on Drug Abuse (NIDA) have found a substance that might do the trick.

The researchers found that mice treated with a substance similar to the drug benztropine didn't show typical hyperactive behavior when later injected with cocaine.

The effect of the treatment wore off after a day.

Cocaine causes euphoria by increasing amounts of the neurotransmitter dopamine sent from neuron to neuron in the brain's reward center.

Dopamine signals pleasure and reward by binding to receptors on neurons. It is normally reabsorbed for later use, but cocaine blocks this mechanism and causes the pleasure chemical to build up.

The benztropine substance operates in a way that's about 10 times slower than cocaine, blocking its effects while not causing the same stimulating effects.

A highly addictive drug, cocaine is thought to be used by between two and 3.2 million people in the US alone, with 1.5 million people there thought to be dependent on it in 2002.

The research is reported in The Journal of Neuroscience.

http://www.betterhumans.com/News/news.aspx?articleID=2005-02-22-1

Gel Acts like Liquid Condom

Topical application in women shown to inhibit HIV and herpes infection
Betterhumans Staff
2/24/2005 4:25 PM

Credit: Uffe Fey
Disease prevention: Like condoms, a new topical microbicide gel for women helps prevent disease, but without the need for partner compliance that can hinder condom use

A gel that acts like a liquid condom to block sexually transmitted diseases has proven to inhibit HIV and herpes infection when used by women.

Researchers at Mount Sinai School of Medicine in New York say that the gel is the first to retain antiviral activity within the human vagina.

"There is an urgent need for the development of safe and effective vaginal microbicides," says Mount Sinai researcher Marla Keller. "While condoms offer protection against sexually transmitted infections, their effectiveness is limited because they require partner initiation or consent."

"Potent activity"

Called PRO 2000 and being developed by Indevus Pharmaceuticals, Inc. of Lexington, Massachusetts, the gel is part of a class of products aimed at preventing sexually transmitted infections when applied topically.

Funded by the US National Institutes of Health, Mount Sinai researchers examined its antiviral activity with the help of 20 HIV-infected women.

Examining vaginal fluid before and one hour after administration of PRO 2000 or a placebo, the researchers found that the gel reduced HIV and herpes simplex virus infectivity by at least 1,000-fold while the placebo had little effect.

"To our knowledge, this is the first time a candidate topical microbicide has been shown to exhibit potent antiviral activity following human administration," says Keller. "The results indicate that PRO 2000 is sufficiently bioavailable and retains substantial antiviral activity one hour after application of a single intravaginal dose. The retention of activity against both viruses is particularly significant in that HSV infection may increase the likelihood of HIV infection."

Large trials underway

Two large clinical trials now aim to assess the effectiveness of PRO 2000 in preventing HIV and other sexually transmitted infections.

One study will enroll about 3,200 women at nine sites in Africa and the US while another will include about 12,000 women in several African countries.

The research was reported in Boston at the 12th Conference on Retroviruses and Opportunistic Infections.


http://www.betterhumans.com/News/news.aspx?articleID=2005-02-24-3

Cloned Meat and Milk Up to Par

Meet industry standards in pilot study addressing potential as food source
Betterhumans Staff

Credit: PNAS
Clone on the range: Meat from four clones of a Japanese Black beef bull and milk from cloned cows meet industry standards

Meat and milk from cloned animals have met industry standards in a pilot study addressing their potential as a food source.

Xiangzhong Yang of the University of Connecticut and colleagues cloned a Japanese Black beef bull and Holstein dairy cow using somatic cell nuclear transfer, the technique used to create Dolly.

The researchers then compared the meat and milk from the clones to that of matched animals bred through natural reproduction.

Based on an evaluation of protein, fat and other factors regularly assessed in the dairy industry, Yang and colleagues found no significant differences in milk.

On 100 meat quality criteria, 90% showed no noteworthy variations. Meat from the cloned animals was found higher on about eight variables related to fat and fatty acids, but the researchers say that these still fall within beef industry standards.

The report provides more information for determining whether products of cloned animals should enter the food chain.

In August 2002, the US National Academy of Sciences concluded that food from cloned animals should be considered safe if no genetic manipulation was involved, and government organizations in several countries, including the US and Japan, have already—if tentatively—said that food from cloned animals is safe.

The new research is reported in the Proceedings of the National Academy of Sciences (read abstract).

http://www.betterhumans.com

Smoking May Alter Genes for Generations

Grandmothers who smoked when pregnant appear to put grandchildren at increased risk of asthma
Betterhumans Staff


Grandmothers who smoke when pregnant appear to put their grandchildren at an increased risk of childhood asthma, suggesting that smoking can alter genes for generations.

"This is the first study to show that if a woman smokes while she is pregnant, both her children and grandchildren may be more likely to have asthma as a result," says Frank Gilliland of the Keck School of Medicine at the University of Southern California. "The findings suggest that smoking could have a longer-lasting impact on families' health than we had ever realized."

Gilliland and colleagues made the finding by interviewing parents or guardians of 908 children participating in the University of Southern California Children's Health Study. The study includes children and teens recruited in grades four, seven and 10. Of these, 338 had asthma by age five.

Double the odds

The researchers found that children whose grandmothers smoked were more than twice as likely—2.1 times the odds—to develop asthma.

Children whose mother didn't smoke while pregnant but grandmother did were 1.8 times as likely to develop asthma. If both mother and grandmother smoked while pregnant, the risk jumped to 2.6 times as likely.

"We suspect that when a pregnant woman smokes, the tobacco might affect her fetus's DNA in the mitochondria, and if it is a girl, her future reproductive cells as well," says Gilliland. "We speculate that the damage that occurs affects the child's immune system and increases her susceptibility to asthma, which is then passed down to her children."

The researchers say that further studies are needed to confirm the results and look more deeply into the relationship.

The research is reported in the journal Chest (read abstract).

http://www.betterhumans.com

"Memory Code" Discovered in Brain

Activity observed in hundreds of mouse neurons simultaneously
Betterhumans Staff



Hundreds of mouse brain cells have been simultaneously recorded in an effort to identify how memories are formed and stored.

To date, brain activity has typically only been measured in a few neurons at a time. However, complex behaviors such remembering involve groups of neurons that work together.

Using a specially developed 96-channel electrode array, Joe Tsien of Boston and Princeton universities and colleagues simultaneously recorded the electrical activity of up to 260 individual neurons in the mouse hippocampus, where memories of places and events are formed.

Exposing electrode-implanted mice to startling stimuli, the researchers found that each startling episode produced different brain activity patterns.

Study revealed that a set of coding units the researchers call "neural cliques" were responsible for encoding. The activation patterns of the coding units appear to be universal across different mice, suggesting a common language for storing memories.

The research is reported in the Proceedings of the National Academy of Sciences (read abstract).

http://www.betterhumans.com

Master Wound Healing Gene Found

Could lead to insights into tissue regeneration and cancer
Betterhumans Staff

A master gene that activates wound healing in insects and mammals has been discovered, a finding that could lead to new insights into tissue regeneration and cancer.

Kimberly Mace and colleagues from the University of California, San Diego found that the master gene, grainyhead, activates wound repair genes in cells surrounding injuries in the outer layer of fly embryos.

Meanwhile, researchers led by Stephen Jane at the Royal Melbourne Hospital in Australia have found that while the outer layer of insects and mammalian skin are chemically different, grainyhead is also essential for normal skin development and wound repair in mice.

"One would envisage that maybe, not too far away, that after an operation that there's a cream or substance that's applied around the wound to stimulate the cells to migrate together to form a nice seamless connection whereby the wound heals without scar," Jane said in an interview.

Permeable skin

Mace and colleagues made their discovery by creating wounds in flies and analyzing DNA sequences to determine that grainyhead initiates repair. They also found that in flies lacking grainyhead, wounds failed to heal.

In their study, Jane and colleagues found that mice lacking grainyhead have more permeable skin than normal mice and have deficient wound repair.

Such a conserved genetic mechanism for wound repair is considered an important find. Little is known about such things as how wound repair is halted when injuries are healed. Nor is it well understood how cancer cells evade this stop program.

"The discovery that grainyhead-like factors are required for the response to injury opens up new avenues of research in the field of wound healing," says Mace. "It also opens new avenues for cancer research, since many cancer cells activate genes normally involved in wound healing in order to kick start processes such as cell division and cell migration."

Both studies are reported in the journal Science.

http://www.betterhumans.com

Babies Can Reason at 15 Months

Previously thought to develop sophisticated reasoning skills at about four years old
Betterhumans Staff
4/15/2005 3:14 PM


Babies just 15 months old display signs of sophisticated reasoning previously thought to develop at about four years of age.

The findings could lead to earlier screening for autism. They also call into question the idea that a large change occurs in early childhood in the understanding of others.

"If 15-month-olds can reason about what others believe, it means that psychological reasoning is much more sophisticated than we thought, and begins at a much earlier age than we had thought," says researcher Renee Baillargeon of the University of Illinois at Urbana-Champaign.

Violation of expectations

Baillargeon and colleagues studied 56 infants who witnessed actors perform unexpected behaviors.

In one study, for example, infants sat on a parent's lap and watched an actor place a toy watermelon slice into one of two boxes.

The slice was then moved from one box to the other seemingly unbeknownst to the actor.

When the actor searched for it in the box where it was, rather than where it was supposed to be, infants expressed surprise in the form of looking longer at the scene.

"Infants understood that the actor could have a true or a false belief about the toy's location, and they always expected her to act in a manner consistent with her belief," says Baillargeon. "This is the violation-of-expectation method: Babies look longer at events they view as unexpected. It is a 'whoa' look—a state of heightened attention. It's like it is in everyday life. You expect something and then when it's not what it should be, you tend to look longer, as when we watch a magic show. It's the wow of the unexpected."

Baillargeon says it's possible that verbal tasks used in earlier works to gauge children's reasoning skills were overly complex.

The research is reported in the journal Science.


http://www.betterhumans.com/

Protein Gives Mice Super Skeletons

Blocks fat production, increases bone mass nearly four times
Betterhumans Staff

A protein that blocks the production of fat in mice also gives them a bone mass four times that of normal mice, hinting at new ways of treating osteoporosis in humans.

The engineered mice have increased levels of a protein called Wnt10b.

In 2004, Ormond MacDougald and colleagues at the University of Michigan Medical School reported that over-expression of Wnt10b in fat cells causes mice to have 50% less body fat and fewer fat cells.

MacDougald and colleagues have now shown that high levels of Wnt10b expression in bone marrow increases bone mass and density, which could have implications for treating such conditions as osteoporosis.

"This is the first identification of a specific signaling protein in the Wnt family that regulates bone formation," says MacDougald.

Pathway regulator

Wnt10b is part of a family of 19 proteins that regulate changes that take place as embryos develop.

Wnt10b appears to affect the fate of bone marrow stem cells that can become either fat cells or bone-forming cells.

It now appears that Wnt10b blocks the fat cell pathway and stimulates the bone-forming pathway. "Which means less fat and more bone," says MacDougald.

No age-related decline

The study involved transgenic mice bred from genetically engineered mouse eggs.

Comparing the bone density in the leg of the mice to that of normal mice, the researchers found that the transgenic animals had almost four times as much bone.

Otherwise, say the researchers, there didn't appear to be any abnormal features in the bone.

The super-skeleton mice also kept their high bone mass as they aged, and even mice with induced estrogen deficiency—a cause of bone loss in women—showed no bone loss.

"Because the transgenic mice have more trabecular bone, or bone within the marrow cavity, to begin with, they are doubly protected from the usual loss of bone density due to estrogen deficiency," says MacDougald.

Potential treatments

Further confirming the role of Wnt10b in bone formation, the researchers found that a strain of mice lacking the gene had 30% lower bone volume and bone mineral density than normal mice.

MacDougald now aims to unravel the molecular mechanism behind Wnt10b's bone-building effect.

"It's not only an important scientific question, it's important to the understanding and potential treatment of osteoporosis and other human diseases," he says. "Right now, there is a need for drugs on the market to stimulate new bone formation. Being able to activate Wnt signaling in bone marrow and osteoblasts might help prevent the loss of bone associated with aging or menopause."

The research is reported in the Proceedings of the National Academy of Sciences.


http://www.betterhumans.com/

'Where Are My Glasses?' -- Study Reveals Clues To The Mechanism Of Short-term Memory

Understanding the biology of memory is a major goal of contemporary neuroscientists. Short-term or "working" memory is an important process that enables us to interact in meaningful ways with others and to comprehend the world around us on a moment-to-moment basis. A study published this week in Science (February 18) presents a strikingly simple yet robust mathematical model of how short-term memory circuits in the brain are likely to store, process, and make rapid decisions about the information the brain receives from the world.

A classic although purely practical example of working memory is our ability to look up a telephone number, remember it just long enough to dial it, and then promptly forget it. However, working memory is fundamental to many other cognitive processes including reading, writing, holding a conversation, playing or listening to music, decision-making, and thinking rationally in a general sense.

Cold Spring Harbor Laboratory computational neuroscientist Carlos Brody explores how brain neurons interact with each other to form the circuits or "neural networks" that underlie working memory and other rapid and flexible cognitive processes.

In the new study, Brody's group developed a mathematical model for interpreting data collected at Universidad Nacional Autónoma de México by his collaborator Rodolfo Romo. Romo's group measured brain neuron activity of macaque monkeys while the animals performed a simple task that involves working memory.

In one version of the task, animals were trained to compare an initial stimulus (a vibration applied to a fingertip) with a second stimulus applied a few seconds later and to immediately provide a "yes" or "no" answer to the question "was the first vibration faster than the second?"

This behavior requires the animals to load the initial stimulus into their working memory ("loading phase"), hold information about that stimulus in their working memory ("memory phase"), and compare that information to the second stimulus and make a decision based on the comparison (the "decision phase").

At the outset of the study, Brody and Cold Spring Harbor Laboratory postdoctoral fellow Christian Machens hoped to develop a mathematical model--based on known properties of "spiking" neurons--that would explain how the brain carries out just the memory phase of the behavior.

To their surprise, the simple "mutual inhibition" model they developed yielded a neural network architecture that explains not only the memory phase, but also the loading phase and the decision phase of the behavior. The model makes several predictions about the neurological basis of working memory that can be tested to confirm the likelihood that the model is a significant advance toward understanding fundamental properties of brain structure and function.


-------------------------------------

This story has been adapted from a news release issued by Cold Spring Harbor Laboratory.

How often should women get mammograms?

New mathematical model predicts live-saving benefits of different screening schedules

WASHINGTON--Researchers at Dana-Farber Cancer Institute in Boston have devised a mathematical tool that predicts how the frequency of mammograms affects the number of lives saved by detecting breast cancers at an earlier stage.

With screening guidelines and financial coverage varying among health systems and insurers – sometimes dramatically – the model provides quantitative predictions of the mortality benefits, on average, in populations of women over the course of 40 years.

"We're not advocating any particular interval for mammography screening," says Sandra Lee, ScD, a biostatistician at Dana-Farber who developed the model along with Marvin Zelen, PhD, of Dana-Farber and the Harvard School of Public Health. "This is a preliminary tool to show policymakers the kind of information they can draw on to help them make decisions."

Lee will describe the development of the mathematical model, which made use of data from several past clinical trials of mammography screening and from cancer databases, in a presentation at the annual meeting of the American Association for the Advancement of Science on Sunday, Feb. 20, 8:30 am (Marriott Wardman Park Hotel, Lobby Level, Maryland Suite C). She also will present that data at a press briefing later that day at 2 pm (Marriott Wardman Park Hotel, Mezzanine Level).

The mathematical tool generates comparative information that's impossible to obtain in the real world, say the scientists, because clinical trials would require hundreds of thousands of volunteers following a variety of schedules over many years to demonstrate small mortality differences – and would be prohibitively expensive. Moreover, adds Lee, such trials would be ethically questionable because of the need for unscreened control groups.

At present, American Cancer Society guidelines recommend that women age 40 and older have a screening mammogram every year and that they "should continue to do so for as long as they are in good health."

But payors differ in their coverage for the tests: in Great Britain, said Zelen, the National Health System pays for mammograms only at three-year intervals and doesn't cover any screening whatsoever for women younger than 50, when the incidence of breast cancer is lower and mammograms are effective.

The model can be helpful to women, he said, by eliminating unnecessary screening exams when the chance of detecting an unknown breast cancer is too low to warrant them.

"It's clear that the more mammograms you give, the more able you are to locate disease that a person didn't know about," Zelen says. But, testing with increasing frequency has diminishing returns, while boosting the odds of "false positives" that can be traumatic to women and lead to unneeded biopsies that drive up health costs.

Lee and Zelen, along with Hui Huang, MS, of Dana-Farber, described the model in 2004 in Statistical Methods in Medical Research. Among their conclusions:


Annual screening from age 50 to 79 of women with average breast cancer risk would reduce mortality by 37 percent – compared to 30 percent with screenings every two years, and 26 percent with mammograms every three years.

Beginning mammograms at age 40 – when breast cancer risk is low – rather than at 50, reduces overall risk of death by five percent because the incidence of cancer in the younger women is very low. However, Zelen said he believes screening women between 40 and 50 has merit because their breast cancers are more aggressive.

If women underwent mammograms every two years beginning at 40 and then annually starting at 50, there would still be a 33 percent reduction in mortality.

Because breast cancer risk increases with age, an alternative screening schedule derived from the model calls for fewer mammograms at early ages, but increasingly often later on. This "threshold" method provides for 18 screenings between 40 and 79, and predicts a mortality reduction of 26 percent.
Women who have a higher breast cancer risk because of their family history are advised to begin mammography at an early age. Using the model, say the researchers, health care providers can determine when to schedule mammograms depending on the amount of a woman's extra risk.

The model also provides estimates of the relative costs incurred by screening populations of women at greater or lesser intervals – an important issue for health policymakers.


###
Dana-Farber Cancer Institute (www.danafarber.org) is a principal teaching affiliate of the Harvard Medical School and is among the leading cancer research and care centers in the United States. It is a founding member of the Dana-Farber/Harvard Cancer Center (DF/HCC), designated a comprehensive cancer center by the National Cancer Institute.



http://www.eurekalert.org/pub_releases/2005-02/dci-hos021705.php

Robots bring hope for amputees

By Los Angeles Times and Washington Post

Washington: Three new robots can walk much like a parent, child and toddler strolling through Central Park, and one requires only about the same amount of human energy to do so.

No one would mistake these mechanical amblers for humans. But the toy-inspired concept behind their realistic movement could prove key to a new generation of robots and more efficient prosthetic limbs, at a time when there has been a surge of leg amputations among Iraq war veterans.

Making its debut at the annual conference of the American Association for the Advancement of Science, one pint-sized robot known as "Robo-Toddler" essentially toddled down a slightly descending table, but proved a bit temperamental when coaxed to walk across a level surface.

Andy Ruina, a professor of theoretical and applied mechanics at Cornell University and another co-author, said the mechanical concept employed in walking was akin to starting to fall and catching yourself, with gravity propelling us along.

The three robots, described in last week's issue of the journal Science, use small motors as gravity substitutions on level surfaces, allowing them to walk in a more human way.

The research also suggests the movement of feet is key to energy-efficient walking.

"You can't know how the foot should work unless you know about its role in how all of walking works," said Steven Collins, a former student of Ruina's who designed a child-sized "efficient walker" robot with freely moving hip and knee joints and motor-stretched springs in each leg that allow its ankles to push off the ground.


He said the accumulating knowledge of the walking motion could be a boon for improving prosthetic limbs.

"Amputees use 20% to 30% more energy to go the same distance or speed as intact in-dividuals," he said. While new prosthetics have added comfort, he said, none has solved the energy problem.

Now a graduate student at the University of Michigan, Collins said he is working toward that goal.

Inspired by late 19th-century toys that used gravity to propel themselves down a slight slope, separate groups at Cornell, MIT and at Delft University of Technology in the Netherlands arrived at more refined robots introduced yesterday.

Although German and Japanese-engineered robots, including the famous Honda Asimo, have been hailed for their life-like range of motion, Ruina said the Asimo robot needs about 10 times as much energy to walk as humans.

Cornell's "efficient" robot, by contrast, requires as little as one-half the wattage of a standard fluorescent bulb. - Los Angeles Times and Washington Post

http://www.dailynews.co.za/

Childhood Brain Cancer

A new approach to treating childhood brain tumors leaves parents with a tough decision.

More than 2,000 children suffer from brain tumors each year in the U.S. Many times, the treatment is as bad, if not worse, than the disease itself. Now, a new approach offers hope -- but not without risk.

Marianna Sanchez has always had a lot to smile about.

"She was such a healthy child, not even a cold," says her mom.

But one day, everything changed.

"She said her head felt like it was going to explode," she remembers.

An MRI detected a very serious brain tumor, known as Medulloblastoma.

"We can cure this, but there are going to be costs, and I think that's probably one ofo the more difficult things I ever have to say to a family," says Dr. Paul Fisher, a Pediatric Neuro-oncologist.

Dr. Fisher says surgery is the easy part.

"That's where the tumor has been successfully removed," he says.

What happens after surgery is more complicated. Without chemo and radiation, the tumor almost always returns. But radiation can cause brain damage -- and possibly even a lower IQ.

"There's a chance they could, say a 2- or 3-year-old, could wind up being mentally retarded," says Dr. Fisher.

Now, some doctors are trying lower doses of radiation to minimize the chance of brain damage. But that could be risky. Here's why.

Some studies show the survival rate is about the same. But others show it may be as much as 10-percent lower. It's a tough decision for parents. Marianna's family chose lower-dose radiation.

"When they mentioned the tradeoff of the mental damage, you know, I said I couldn't do this to her. We were very focused on not changing her, kind of her going into this thing and coming out the same person," says Mariana's mom.

For Marianna, it's paid off. Two years later, she's cancer-free and past the point when most tumors return.

Medulloblastoma is the most common cancerous brain tumor in children.

Doctors believe it's caused by a combination of genetic and environmental factors.

The typical survival rate for children with these types of brain turmors is between 60 and 80 percent.

Log on to www.ivanhoe.com for more information.


http://www.wqad.com/Global/story.asp?S=3648587

¿Podría volver el Vioxx? (inglés)

Merck's top scientist now says he would consider putting Vioxx back on the market.

Research chief Peter Kim announced the news before an advisory panel to the Food and Drug Administration. Doctors on the panel were debating whether Celebrex and Bextra, two Pfizer (nyse: PFE - news - people ) medicines that work similarly to Vioxx, cause heart attacks and whether their risks mean patients should no longer have access to them. Also up for debate were older drugs such as ibuprofen, sold by Johnson & Johnson (nyse: JNJ - news - people ) as Motrin.

After looking nervous for some time, Kim stepped up to the microphone and waited for the panel's head to address him. When Merck (nyse: MRK - news - people ) pulled Vioxx off the market because it increased the risk of heart attacks and strokes, it had stated that the company believed it would be possible to continue to market Vioxx with a strong warning label. Now, he said, the science was again evolving and some therapies that had looked safe for the heart may not be.

"Given this new data," Kim said, "it is not clear that the cardiovascular risk seen in Approve makes Vioxx unique in the class of similar drugs marketed in the U.S." Approve is the cancer-prevention study that turned up the heart risk for Vioxx.

Vioxx, he pointed out, was the only medicine that eased some patients' pain. It was the only drug in its class proven to reduce the risk of gastrointestinal problems, and it lacks the potential for a type of allergy seen in both Celebrex and Bextra. "Merck is a data-driven company," Kim said. However, he said the company has not altered its position on the withdrawal of Vioxx, and that to say anything further would be "speculation."

Kim said he's looking forward to hearing the advisory committee's thoughts and concerns, and to discussing the outcomes of the meeting. For tonight, at least, ahead of most of the FDA panel's biggest decisions, investors will be happy to speculate.

Garret FitzGerald, a pharmacologist at the University of Pennsylvania, said that he thought the move would help recapture the lost value of the drug to some patients. "It does illustrate the value of recognizing a problem and dealing with it."

http://www.forbes.com

Robots Learn to Walk

For the first time, mimic human gait and energy efficiency
Betterhumans Staff


Credit: Cornell University
A step forward: One of three new robots with humanlike walking ability, this robot by Cornell University researchers nearly matches human efficiency in movement

Robots have been constructed that for the first time mimic human gait and energy efficiency.

The robots integrate concepts from "passive-dynamic walkers," devices similar to children's toys around since the 1800s that walk down a shallow slope using the pull of gravity.

The toys work by swaying from side to side, allowing one foot at a time to swing forward.

For the robots, researchers simply substituted small motors for gravity power.

More efficient than Asimo

Independently developed by researchers at Cornell University in New York, the Massachusetts Institute of Technology and Delft University of Technology in The Netherlands, the robots are furthering understanding of bipedal motion as well as human locomotion and motor learning.

Insight from the work is also being applied to the development of robotic prostheses.

All of the robots are far more efficient than what's likely the world's most famous bipedal robot, Honda's Asimo. The researchers estimate that Asimo uses at least 10 times as much energy as a human.

The Cornell robot approaches human efficiency, able to walk on level ground while using as little as one-half the wattage of a standard compact fluorescent bulb.

Simple mechanics

The Cornell robot supplies power to the ankles to push off.

When the front foot hits the ground, a simple microchip controller tells the rear foot to push off.

With the forward swing of each leg, a small motor stretches a spring that is released to provide the push.

The Delft robot uses a pneumatic push at the hip, while the MIT robot uses electric motors that directly move the ankle.

All three robots have arms synchronized to swing with the opposite leg for balance.

Machine toddlers

While control programs are simple in the Cornell and Delft robots because of their mechanical design, the MIT robot—"Toddler"—uses a program that allows it to learn how to walk in less than 20 minutes or 600 steps.

The fact that the robots can walk like humans with simple control programs "suggests that steady-state human walking might require only simple control as well," the researchers say.

The robots will be reported in the journal Science.

They were unveiled in Washington, DC at the annual meeting of the American Association for the Advancement of Science.

http://www.betterhumans.com