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Breastfeeding boosts mental health

A new study has found that babies that are breastfed for longer than six months have significantly better mental health in childhood.

The findings are based on data from the ground-breaking Raine Study at the Telethon Institute for Child Health Research, that has tracked the growth and development of more than 2500 West Australian children over the past 16 years.

Researcher Dr Wendy Oddy said there was growing evidence that bioactive factors in breast milk played an important role in the rapid early brain development that occurs in the first year of life.

"Even when we adjust the results to take into account other factors such as the parents' socio-economic situation, their education, their happiness and family functioning, we see that children that were breastfed for at least six months are at lower risk of mental health problems," Dr Oddy said.

The study found that children who were breastfed for less than six months compared to six months or longer had a 52% increased risk of a mental health problem at 2 years of age, a 55% increased risk at age 6, at age 8 the increased risk was 61% while at age 10 the increased risk was 37%.

The analysis is based on a scientifically recognised checklist of child behaviour that assessed the study children's behaviour at 2, 6, 8 and 10 years of age.

Dr Oddy said that children that were breastfed had particularly lower rates of delinquent, aggressive and anti-social behaviour, and overall were less depressed, anxious or withdrawn.

"These results are powerful evidence for more support to be given to mothers to help them breastfeed for longer," she said.

Babies say 'thank you' as new research reveals breastfeeding boosts mental health

A new study has found that babies that are breastfed for longer than six months have significantly better mental health in childhood.

The findings are based on data from the ground-breaking Raine Study at the Telethon Institute for Child Health Research, that has tracked the growth and development of more than 2500 West Australian children over the past 16 years.

Researcher Dr Wendy Oddy said there was growing evidence that bioactive factors in breast milk played an important role in the rapid early brain development that occurs in the first year of life.

"Even when we adjust the results to take into account other factors such as the parents' socio-economic situation, their education, their happiness and family functioning, we see that children that were breastfed for at least six months are at lower risk of mental health problems," Dr Oddy said.

The study found that children who were breastfed for less than six months compared to six months or longer had a 52% increased risk of a mental health problem at 2 years of age, a 55% increased risk at age 6, at age 8 the increased risk was 61% while at age 10 the increased risk was 37%.

The analysis is based on a scientifically recognised checklist of child behaviour that assessed the study children's behaviour at 2, 6, 8 and 10 years of age.

Dr Oddy said that children that were breastfed had particularly lower rates of delinquent, aggressive and anti-social behaviour, and overall were less depressed, anxious or withdrawn.

"These results are powerful evidence for more support to be given to mothers to help them breastfeed for longer," she said.

For a World of Woes, We Blame Cookie Monsters

By GINA KOLATA


FIRST we said they were ruining their health with their bad habit, and they should just quit.

Then we said they were repulsive and we didn’t want to be around them. Then we said they were costing us loads of money — maybe they should pay extra taxes. Other Americans, after all, do not share their dissolute ways.

Cigarette smokers? No, the obese.

Last week the list of ills attributable to obesity grew: fat people cause global warming.

This latest contribution to the obesity debate comes in an article by Sheldon H. Jacobson of the University of Illinois at Champaign-Urbana and his doctoral student, Laura McLay. Their paper, published in the current issue of The Engineering Economist, calculates how much extra gasoline is used to transport Americans now that they have grown fatter. The answer, they said, is a billion gallons a year.

Their conclusion is in the same vein as a letter published last year in The American Journal of Public Health. Its authors, from the Centers for Disease Control and Prevention, did a sort of back-of-the-envelope calculation of how much extra fuel airlines spend hauling around fatter Americans. The answer, they wrote, based on the extra 10 pounds the average American gained in the 1990’s, is 350 million gallons, which means an extra 3.8 million tons of carbon dioxide.

“People are out scouring the landscape for things that make obese people look bad,” said Kelly Brownell, director of the Rudd Center for Food Policy and Obesity at Yale.

And is that a bad thing? Dr. Jacobson doesn’t think so. “We felt that beyond public health, being overweight has many other socioeconomic implications,” he said, which was why he was drawn to calculating the gasoline costs of added weight.

The idea of using economic incentives to help people shed pounds comes up in the periodic calls for taxes on junk food. Martin B. Schmidt, an economist at the College of William and Mary, suggests a tax on food bought at drive-through windows. Describing his theory in a recent Op-Ed article in The New York Times, Dr. Schmidt said people would expend more calories if they had to get out of their cars to pick up their food.

“We tax cigarettes in part because of their health cost,” he wrote. “Similarly, the individual’s decision to lead a sedentary lifestyle will end up costing taxpayers.”

Eric Oliver, a political scientist at the University of Chicago, said his first instinct was to laugh at the gas and drive-through arguments. But such claims often get wide attention, he says, and take on a life of their own.

“This is like, let’s find another reason to scapegoat fat people,” Dr. Oliver says.

At an annual meeting of the Obesity Society, one talk correlated obesity with deaths in car accidents, and another correlated obesity with suicides. Dr. Oliver, who attended, said no one in the crowd of at least 200 questioned whether the correlations were really cause and effect. “The funny thing was that everyone took it seriously,” he said.

Katherine Flegal of the Centers for Disease Control and Prevention also wryly cautions against being quick to link cause and effect. “Yes, obesity is to blame for all the evils of modern life, except somehow, weirdly, it is not killing people enough,” she said. “In fact that’s why there are all these fat people around. They just won’t die.”

The message in the blame-obesity approach, said James Marone, a political science professor at Brown University, is that it is so important to persuade fat people to lose weight that common sense disappears.

“Anything we can say to persuade you, we will say,” Dr. Marone added.

So is it working?

It doesn’t seem to be. Fat people are more reviled than ever, researchers find, even as more people become fat. When smokers and heavy drinkers turned pariah, rates of smoking and drinking went down. Won’t fat people, in time, follow suit?

Research suggests that the stigma of being fat leads to more eating, not less. And if reducing the stigma suggests a solution, that’s not working either.

“One hypothesis about getting rid of stigma is having more contact with the stigmatized group,” Dr. Brownell says. But with obesity, the stigma seems to be growing along with the national girth.

He cites a famous study in the 1960’s in which children were shown drawings of children with and without disabilities, as well as a drawing of a fat child. Who, they were asked, would you want for your friend? The fat child was picked last.

Now, three researchers have repeated the study, this time with college students. Once again, almost no one, not even fat people, liked the fat person. “Obesity was highly stigmatized,” wrote the researchers, Janet D. Latner of the University of Canterbury in New Zealand, Albert J. Stunkard of the University of Pennsylvania and C. Terence Wilson of Rutgers University, in the July 2005 issue of Obesity Research.

One problem with blaming people for being fat, obesity researchers say, is that getting thin is not like quitting smoking. People struggle to stop smoking, but many, in the end, succeed. Obesity is different. It’s not that the obese don’t care. Instead, as science has shown over and over, they have limited personal control over their weight. Genes play a significant role, the science says.

That is not a popular message, Dr. Brownell says. And the notion that anyone can be thin with a little effort has consequences. “Once weight is due to a personal failing, a lot of things follow,” he said. There’s the attitude that if you are fat, you deserve to be stigmatized. Maybe it will motivate you to lose weight. The opposite happens.

In a paper published Oct. 10 in Obesity, Dr. Brownell and his colleagues studied more than 3,000 fat people, asking them about their experiences of stigmatization and discrimination and how they responded.

Almost everyone said they ate more.
World's first full-face transplant likely in UK

* 12:40 25 October 2006

* NewScientist.com news service

* NewScientist.com and AFP

The world's first full-face transplant may be performed within months after a British hospital was given the go-ahead by its ethics committee on Wednesday.

Consultant plastic surgeon Peter Butler said he was "delighted" to have been given permission for the pioneering surgery by the committee at the Royal Free Hospital in Hampstead, north London.

"We can now begin to evaluate patients and draw up a shortlist of four people who want to undergo this procedure," he said. "We will continue to take a cautious and careful approach and we will not be rushed. It may be many months before we are ready to carry out an operation."

The prospect of a full-face transplant raises hopes for people with severe facial disfigurement – caused by burns or disease, for example – and comes after surgeons in France carried out the world's first partial face transplant in November 2005.

Isabelle Dinoire, who had her nose, lips and chin replaced after she was savaged by a dog, is reportedly happy with the result. "I have now a face like everyone else," she said in February 2006, when she faced the press for the first time.

In April 2006, a hospital in China conducted what is believed to be the second partial face transplant on Li Guoxing, aged 30, who had been attacked by a bear.



Patient selection

Patients selected for the proposed full-face transplant will only be considered if they are from the UK or Ireland, due to concerns about the long-term care of overseas patients in Britain's publicly-funded National Health Service. Butler said he would not be able to carry out the operation on children, because of issues of consent.

All the patients are likely to have pan-facial disfigurement, where the whole face has been affected by injury, spreading to the scalp or ears.

"These patients will have already undergone reconstructive surgery. Perhaps they will have had 50 or 70 reconstructive operations," says Butler, who adds that he has already been approached by 34 patients from across the world.

"They have reached the end of the reconstructive ladder and there's nothing more it can offer them. They have the problem of integration into society, of being able to walk down the street in society without anybody staring at them. That's all these people want – to be normal," he says.

Detailed scrutiny

Computer modelling has shown that the recipient of a full-face transplant would look different to the donor because of their face shape and bone structure.

Andrew Way, chief executive of the trust that runs the Royal Free Hospital, said the committee gave the green light only after "the most detailed scrutiny" of more than 10 years' research by Butler's team.

After the first transplant – which is likely to take 10 to 12 hours and involve four to six surgeons – there will be a six-month gap before the second operation to assess the procedure.

Changing Faces, a UK-based organisation for people with facial disfigurements, said that patients considered for the procedure must have a full understanding of the risks and benefits, especially the risks associated with taking immunosuppressant drugs for life, which are needed to prevent rejection of the new facial tissue.

“A viable 'Plan B' should be developed and explained in the event of a transplant being rejected and every effort must be made to protect the patient’s privacy and that of the donor’s family,” the charity added.


Late motherhood may risk infertility in daughters

* 16:16 25 October 2006

* NewScientist.com news service

* Phil McKenna

Women who put off pregnancy until late in life not only jeopardise their own chances of bearing children, but may place their daughter’s fertility at risk as well.

A new study found that the mothers of infertile women tended to be older and closer to menopause when their daughters were conceived compared with the mothers of women who became pregnant. And as women wait longer and longer to have children, the affects could increase dramatically.

“In one or two generations, we could have serious problems and it could start to accumulate; it could have an additive affect,” warns Zsolt Nagy of Reproductive Biology Associates in Atlanta, Georgia, US.

Nagy and colleagues examined 74 patients who were using IVF to treat infertility. Women who did not become pregnant were themselves conceived an average of 20 years before their mothers reached menopause, the team found.

Gene expression

However, women who did become pregnant through IVF had been conceived earlier on in their mothers’ reproductive lives – an average of 25 years before menopause.

Nagy suspects that eggs from older women may have impaired gene expression that goes unnoticed until their female offspring try to conceive. “All the genes are there,” he says of the daughters' infertile eggs, “but they aren’t functioning correctly.”

He suggests it is “very likely” that the findings apply to women generally and not just to women seeking treatment for infertility. Nagy presented his findings at the American Society for Reproductive Medicine conference in New Orleans, US, on Tuesday.


It's the next best thing to a Babel fish

* 26 October 2006

* From New Scientist Print Edition. Subscribe and get 4 free issues

* Celeste Biever

Imagine mouthing a phrase in English, only for the words to come out in Spanish. That is the promise of a device that will make anyone appear bilingual, by translating unvoiced words into synthetic speech in another language.

The device uses electrodes attached to the face and neck to detect and interpret the unique patterns of electrical signals sent to facial muscles and the tongue as the person mouths words. The effect is like the real-life equivalent of watching a television show that has been dubbed into a foreign language, says speech researcher Tanja Schultz of Carnegie Mellon University in Pittsburgh, Pennsylvania.

Existing translation systems based on automatic speech-recognition software require the user to speak the phrase out loud. This makes conversation difficult, as the speaker must speak and then push a button to play the translation. The new system allows for a more natural exchange. "The ultimate goal is to be in a position where you can just have a conversation," says CMU speech researcher Alan Black.

In October 2005 Schultz and her colleague Alex Waibel demonstrated the first automatic translator that could pick up electrical signals from face and throat muscles and convert them into text or synthesised speech - a technique called sub-vocal speech recognition. This ran on a laptop and translated Mandarin Chinese to English or Spanish, but it could only translate around 100 words, each of which had first to be spoken into the system by the user, to "train" it on their voice.

Now the team has developed a system that can recognise a potentially limitless lexicon. Their secret is to detect not just words but also the phonemes that form the building blocks of words. The system then uses these to reconstruct the word. To translate from English to another language, the user only has to train the system on the 45 phonemes used in spoken English.

The researchers use software that has been taught to recognise which phonemes are most likely to appear next to each other and in what order. When it encounters a string of phonemes it is unfamiliar with or has only partially heard, it uses this knowledge to come up with a range of sequences that make sense given the surrounding phonemes and words, assigns a probability to each one, and then picks the one with the highest probability.

The system still has some way to go. Faced with a sequence of words it has never heard before, it picks the right phoneme sequence only 62 per cent of the time. This nevertheless ranks as "a very significant achievement" according to Chuck Jorgensen, who is working on using sub-vocal speech recognition to control robots at NASA's Ames Research Center in Moffett Field, California. "This is showing that the technology is really within reach."

Schultz's team plan to attach the phoneme recognition software to their prototype Spanish or German translators, once they have improved its accuracy.



From issue 2575 of New Scientist magazine, 26 October 2006, page 32
Fasting may boost recovery from spinal injury

* 16:43 26 October 2006

* NewScientist.com news service

* Roxanne Khamsi

Fasting may improve recovery from spinal cord injury, according to a new rodent study.

Injured rats that were only fed on alternate days showed half the spinal cord damage compared with their normally fed counterparts after several months. The findings add to a growing body of evidence that calorie restriction can boost recovery from a variety of injuries.

Ward Plunet at the University of British Columbia in Vancouver, Canada, and colleagues created lesions in the spinal cords of a group of rats. Half of the animals were able to eat whenever they wanted, while the other “fasting” half were fed only every other day.

Over the course of these two months following the initial spinal injury, fasting rats showed slightly better improvement in their ability to complete a ladder-climbing task than their counterparts. Inspection of the rodents’ spinal cords then revealed that the lesions were 50% smaller in the fasting animals than the control animals.



Overzealous cells

Other studies have shown that a calorie restricted diet started several months before an injury such as stroke can protect neurons from dying. This is the first to show that calorie restriction can help after injury too, Plunet believes.

He suspects that fasting helps because it dampens the body’s immune system, causing fewer overzealous immune cells to reach the site of spinal injury. These cells sometimes block off the site of injury to such an extent that they prevent nerve regeneration.

Calorie restriction appears to make the cells in the spinal cord more sensitive to growth-promoting proteins, Plunet adds. Spinal cord biopsies from the animals in his study showed that the cells of fasting rats had more functional copies of a receptor that responds to a chemical that boosts nerve growth.



Profound changes

The study findings may seem counterintuitive, since people who are sick are often encouraged to eat more to help their body heal, Plunet admits.

“The findings challenge conventional medical protocols for severely ill, traumatised patients,” says neurosurgeon Michael Fehlings at Toronto Western Research Institute, Canada.

However, he says, patients with spinal cord injury have undergone a major trauma to their body, which can result in profound metabolic changes that potentially leave them at risk of malnutrition, which fasting may exacerbate.

“Nonetheless, the current research is of major interest and suggests a novel therapeutic approach for spinal cord injury,” Fehlings adds.

Plunet presented the findings at the annual Society for Neuroscience meeting in Atlanta, Georgia, last week.


Introducing humans version 2.0

By James van der Pool

BBC Horizon

The half-human, half-robot cyborg has long been a vision nurtured by science fiction writers and futurologists. But how close are we to humans version 2.0, computer-enhanced people?

Ray Kurzweil, a renowned American inventor and futurist, supplements his daily diet with a cocktail of 250 pills. Now in his mid-fifties, Kurzweil is attempting to extend his life until 2029.

This is when he believes science will have made two huge breakthroughs; understanding how the human mind works and the creation of computers that are equal to its power.

If Mr Kurzweil is right the implications could be profound.

"In 25 years from now... we will have both the hardware and the software to recreate human intelligence in a machine," he says.

Once computers have the processing power of the human brain it will be possible to enhance our intelligence with silicon implants and even download the contents of our minds to machines, preserving them forever.

Mr Kurzweil is saying that in just a few decades humans could, in effect, become immortal.

Rehashed sci-fi

Although his vision may sound like rehashed sci-fi fantasy it is based on the closely observed trends in the fields of computer and neuroscience.

As far back as 1964, Gordon Moore, a founder of the computer chip firm Intel, predicted that computer power would double every year.

Moore turned out to be right and his simple idea offers up a staggering statistic, as Kurzweil points out: "Computers are about a billion times more powerful than they were a quarter century ago and they will become a billon times more powerful than they are today in a quarter century."

But whilst there may be an almost metronomic predictability about the progress of computers toward Kurzweil's dateline, neuroscience inhabits a far more complex and controversial arena.

In order to unlock the secrets of the human mind, neuroscientists often turn to other species, with some extraordinary results.

At the State University of New York, Professor John Chapin has come up with a unique interface between animal and machine - a remote control rat.

Prof Chapin transmits radio signals to electrodes placed in the area of the rat's brain that controls its whiskers.

When he sends a signal to the right whisker the rat turns right. If the rat does as asked, Chapin rewards it with another signal to its pleasure centre.

Rat's mind

Bizarre as it sounds, by commanding the rat's mind, Prof Chapin hopes to discover the exact function of the different parts of its brain.

Professor Miguel Nicolelis at Duke University in North Carolina, has taken this paradigm of brain machine interfaces even further.

For the past decade, he has been tapping in to the brains of monkeys by wiring them up to computers and eavesdropping on their thoughts.

Prof Nicolelis acknowledges how surprisingly fertile this approach has been.

"The brain was considered the last frontier, the impenetrable part of us, and we are just learning that we can actually go in there and read thoughts," he says.

Prof Nicolelis has refined his decoding of the mind to such a degree that his monkeys are able to control extraneous devices, such as robotic arms, through thought alone.



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