Virtual massage' can relieve amputees' phantom limb pain
Amputees who experience phantom limb pain could find relief in a surprisingly simple way - by paying more attention to the people around them.
Phantom limbs occur when an amputee feels the often painful sensation of touch arising from a limb that is no longer present. Working with combat veterans, Vilayanur Ramachandran, of the Center for Brain and Cognition at the University of California, San Diego, has now discovered a potential cure.
His treatment makes use of the newly discovered properties of mirror neurons. Mirror neurons fire when a person performs an intentional action - such as waving - and also when they observe someone else performing the same action. They are thought to help us predict the intentions of others by creating a "virtual reality" simulation of the action in our minds.
"You also find cells like this for touch," says Ramachandran. "They fire when you touch yourself and when you watch someone else being touched in the same location."Massaging the skin helps relieve a painful sensation by restoring blood flow and activating sensory fibres, which inhibit pain messages to the brain. By watching another person rubbing their hand, these amputees are apparently tapping into this latter mechanism, says Ramachandran. source
Why men should pair off with younger women
Mick Jagger, Rupert Murdoch and Michael Douglas all have the right idea, evolutionarily speaking. Statistics show that monogamous men have the most children if they marry women younger than themselves. How much younger is the key question.
Last year, a study of Swedish census information suggested a 4 to 6-year age gap is best, but new research has found that in some circumstances a surprisingly large gap – 15 years – is the optimum.
Martin Fieder at the University of Vienna and Susanne Huber of the University of Veterinary Medicine, also in Vienna, Austria, studied the Swedish data and found that a simple equation related the age difference of the parents to the number of offspring. For people who had maintained monogamous relationships throughout adulthood, the most children were found in couples where the man was 4.0 to 5.9 years older than the woman.
The probable reasons behind this state of affairs are not controversial: "Men want women younger than themselves because they are physically attractive," says Fieder, while women tend to prioritise a partner who can provide security and stability, and so tend to opt for older men. source
In recent years, crystal meth (methamphetamine) and ecstasy (MDMA) have become some of America's top problem drugs. Meth can cause severe problems in the cardiovascular and central nervous systems. Furthermore, because there is no way to remove the drug from the body, therapies tend to focus on treating its side-effects.
But antibodies that bind to methamphetamines and methamphetamine-like compounds to effectively remove them from the bloodstream could change that. Michael Owens, director of the Center for Alcohol and Drug Abuse at the University of Arkansas, US, and colleagues claim to have developed a way to generate them.
The team have not yet tested the antibodies in humans, only in rats, but they say that a single injection can reduce the level of drug within the bloodstream for several days. By binding to drug molecules, the antibodies prevent them from reaching tissues like the heart and brain, and mark the compounds for clean up by the body.
Owens says that his team's antibodies bind to many drugs from the same chemical "family". Cocaine and nicotine are single, specific compounds but methamphetamines share a basic chemical skeleton with many other drugs. So-called "designer drugs" are made by modifying this skeleton to create specific effects. The team say their therapy works for meth, amphetamines and ecstasy.
Genome is a snip at $60,000
WHEN the cost of sequencing a human genome gets down to the price of a family car, then the era of personalised genomics will truly be upon us. This was the prediction from James Watson, co-discoverer of the structure of DNA, in an interview with New Scientist (20 October 2007, p 58) last year.
Well, it's getting close. Last week, Applied Biosystems of Foster City, California, announced that it had sequenced the genome of a Nigerian man at a cost of less than $60,000, excluding labour. "We are committed to pushing the limits of this technology," says Shaf Yousaf of Applied Biosystems. "These prices will come down further in the next year or two."
Several companies are already offering partial personal-genome scans, based on single-letter changes in parts of the genome, for about $1000. Cheap full-genome sequencing would help us to understand why people differ from others, and could help determine whether someone was at risk of a particular disease. source
Carbon monoxide could fight disease
CARBON monoxide, that notorious killer, could also be a life-saver. A small quantity of the gas given to people with a potentially fatal lung disease led to signs of improvement in their condition. It is also showing promise for treating other chronic and acute inflammatory conditions.
At high concentrations, carbon monoxide (CO) displaces oxygen from red blood cells, and in effect kills by asphyxiation. Its healing effects have emerged in ongoing experiments in animals, which show that low levels of CO can reduce inflammation and oxidative damage to tissue.
In fact CO is produced as a normal part of a reaction that generates antioxidants in the blood when tissues are inflamed. It was once dismissed as a worthless by-product of this reaction, but now it seems that the gas itself has the ability to calm inflammation in humans too. source
More on that study:here
Mic based on fly ear can pinpoint soundsIT MAY be inspired by a humble fly, but a sensor just a couple of centimetres in diameter could turn out to be the best microphone yet for pinpointing the source of a sound. The device could be added to hearing aids or mounted on autonomous robotic vehicles to locate cries for help during disaster relief efforts.
Humans detect slight differences in the timing of sound waves as they arrive at each eardrum and use this to reconstruct where a sound is coming from. However, the differences are only noticeable because our eardrums are at least a few centimetres apart. In contrast, despite the small distance between its two eardrums, the parasitic fly Ormia ochracea can pinpoint a sound source far more accurately than humans.Its secret is a chitin bridge that links the fly's eardrums. source