Medicine & Health
edyong | March 30, 2009
For all appearances, this looks like the skull of any human child. But there are two very special things about it. The first is that its owner was clearly deformed; its asymmetrical skull is a sign of a medical condition called craniosynostosis that's associated with mental retardation. The second is that the skull is about half a million years old. It belonged to a child who lived in the Middle Pleistocene period.
The skull was uncovered in Atapuerca, Spain by Ana Gracia, who has named it Cranium 14. It's a small specimen but it contains enough evidence to suggest that the deformity was…
neurophilosophy | March 27, 2009If someone told you that they wanted to have a perfectly good leg amputated, or that they have three arms, when they clearly do not, you would probably be inclined to think that they are mentally disturbed. Psychiatrists, too, considered such conditions to be psychological in origin. Voluntary amputation, for example, was regarded as a fetish, perhaps arising because an amputee's stump resembles a phallus, whereas imaginary extra limbs were likely to be dismissed as the products of delusions or hallucinations.
However, these bizarre conditions - named body integrity identity disorder (BIID)…
edyong | March 9, 2009Pregnant women are generally advised to avoid drinking alcohol and for good reason - exposing an unborn baby to alcohol can lead to a range of physical and mental problems from hyperactivity and learning problems to stunted growth, abnormal development of the head, and mental retardation.
But alcohol also has much subtler effects on a foetus. Some scientists have suggested that people who get their first taste of alcohol through their mother's placenta are more likely to develop a taste for it in later life. This sleeper effect is a long-lasting one - exposure to alcohol in the womb has been…
edyong | February 25, 2009
Alzheimer's disease is the most common form of dementia in the world, affecting more than 26 million people. Creutzfeld-Jacob disease (CJD), another affliction is far less common, but both conditions share many of the same qualities. They are fatal within a few years of diagnosis, they are incurable and they involved the crippling degeneration of the brain's neurons. Now, a group of Yale researchers have discovered that the two diseases are also linked by a pair of critical proteins.
Look into the brain of someone with Alzheimer's disease and you will see large, insoluble "plaques" sitting…
edyong | February 21, 2009
When people say that every cloud has a silver lining, they probably aren't thinking about herpes at the time. Herpes may be unpleasant, but the viruses that cause it and related diseases could have a bright side. In mice at least, they provide resistance against bacteria, including the bubonic plague.
Herpes is one of a number of itchy, blistering diseases, caused by the group of viruses aptly-named herpesviruses. Eight members infect humans and cause a range of illnesses including glandular fever, chickenpox, shingles and, of course, herpes itself.
Almost everyone gets infected by one of…
edyong | February 15, 2009
A child in the womb is not just some hapless creature waiting to be born into a world of experience. It is preparing. Through its mother, it senses the conditions of the world outside and its body plans its growth accordingly.
There is strong evidence that people who are under-nourished as embryos grow up to have higher risks of heart disease and other chronic illnesses. For example, people born to women during the Dutch Famine of 1945 had higher risks of coronary heart disease as adults.
We might nod our heads at this as if it were expected news, but it's actually quite a strange result…
edyong | February 12, 2009This is the eighth of eight posts on evolutionary research to celebrate Darwin's bicentennial.
In Virginia, USA, sits a facility called the American Type Culture Collection. Within its four walls lie hundreds of freezers containing a variety of frozen biological samples and among these, are 99 strains of the common cold. These 99 samples represent all the known strains of the human rhinoviruses that cause colds. And all of their genomes have just been laid bare.
Ann Palmenberg from the University of Wisconsin and David Spiro from the J. Craig Venter Institute have cracked the genomes of all…
edyong | February 3, 2009Our health isn't just affected by the things we do after we're born - the conditions we face inside our mother's womb can have a lasting impact on our wellbeing, much later in life. This message comes from a growing number of studies that compare a mother's behaviour during pregnancy to the subsequent health of her child.
But all of these studies have a problem. Mothers also pass on half of their genes to their children, and it's very difficult to say which aspects of the child's health are affected by conditions in the womb, and which are influenced by mum's genetic legacy.
Take the case…
edyong | January 26, 2009People diet for many reasons - to fit into clothes, to look more attractive, or for the sake of their health. But to improve their memory? It's an interesting idea, and one that's been given fresh support by Veronica Witte and colleagues from the University of Munster in Germany.
Witte found that elderly people who slash the calories in their diet by 30% were better able to remember lists of words than people who stuck to their normal routine. It's the first experiment to show that cutting calories can improve human memory at an age when declining memory is par for the course.
The benefits…
edyong | January 16, 2009
Using genetic engineering, a group of scientists have developed a way of sneaking a virus past the brain's defences. Don't panic - this isn't some nightmare scenario. It could be the first step to curing a huge number of brain diseases.
The brain seems incredibly well protected amid its shell of bone and cushioning fluid. But even the strongest of forts needs supply lines, and brain is no exception.
A dense network of blood vessels carries vital oxygen to its cells. These vessels are a potential vulnerable spot, providing access for bacteria and other disease-causing organisms to migrate…
edyong | January 11, 2009You've just been in a horrific car crash. You're unharmed but the vividness of the experience - the sight of a looming car, the crunching of metal, the overwhelming panic - has left you a bit traumatised. You want something to help take the edge off and fortunately a doctor is on hand to prescribe you with... Tetris.
Yes, that Tetris. According to Emily Holmes from the University of Oxford, the classic video game of falling coloured blocks could prevent people who have suffered through a traumatic experience from developing full-blown post-traumatic stress disorder (PTSD). As ideas go, it's…
edyong | January 1, 2009The mosquito Aedes aegypti sucks the blood of people from all over the tropics, and exchanges it for the virus that causes dengue fever - a disease that afflicts 40 million people every year. The mosquito has proven to be a tough adversary and efforts to drive it from urban settings have generally failed in the long-term. So how do you fight such an accomplished parasite? Simple - use a better parasite. In fact, try the most successful one in the world, a bacterium called Wolbachia.
Wolbachia's success rests on two traits. First, it targets the most diverse group of animals on the planet,…
edyong | December 22, 2008
The video above seems completely unremarkable at first - man walks down a corridor, navigating his way around easily visible and conspicuous obstacles. But it's far from an easy task; in fact, it should be nigh-impossible. The man, known only as TN, is totally blind.
His inability to see stems from a failure in his brain rather than his eyes. Those work normally, but his visual cortex - the part of the brain that processes visual information - is inactive. As a result, TN is completely unaware of the ability to see and in his everyday life, he behaves like a blind person, using a stick to…
edyong | December 13, 2008When normal bacteria are exposed to a drug, those that become resistant gain a huge and obvious advantage. Bacteria are notoriously quick to seize upon such evolutionary advantages and resistant strains rapidly outgrow the normal ones. Drug-resistant bacteria pose an enormous potential threat to public health and their numbers are increasing. MRSA for example, has become a bit of a media darling in Britain's scare-mongering tabloids. More worryingly, researchers have recently discovered a strain of tuberculosis resistant to all the drugs used to treat the disease.
New antibiotics are…
neurophilosophy | December 9, 2008The top medical breakthrough of the year, according to TIME Magazine, is the creation of motor neurons from ALS patients. (Here are all 50 of the magazine's Top 10 lists for 2008.)
This work was carried out by researchers at Harvard and Columbia universities, and published in the journal Science back in August. I wrote about it at the time: skin cells were taken from an 82-year-old ALS patient and made to de-differentiate into pluripotent stem cells, which were then reprogrammed to form motor neurons, the cell type which degenerates in ALS.
This research is significant for two reasons. First…
edyong | December 1, 2008You are not alone. Even if you're currently reading this in complete isolation, you are still far from a singular individual. You're more of a colony - one human, together with microbes in their trillions. For every one of your own genes, your body is also host to thousands of bacterial ones. Some of the most important of these tenants - the microbiota - live in our gut. Their genes, collectively known as our microbiome, provide us with the ability to break down sources of food, like complex carbohydrates, that we would otherwise find completely indigestible.
Peter Turnbaugh from the…
neurophilosophy | November 26, 2008The term body image was coined by the great neurologist Henry Head and refers to a mental representation of one's physical appearance. Constructed by the brain from past experience and present sensations, the body image is a fundamental aspect of both self-awareness and self-identity, and can be disrupted in many conditions.
Disruption of the body image can have profound physical and psychological effects. For example, body image distortion is implicated in eating disorders such as anorexia nervosa, and also leads to phenomena such as phantom limb syndrome and body dysmorphic disorder;…
neurophilosophy | November 19, 2008
Fox 10 News has a rather gruesome story about the removal of a live parasitic worm from a woman's brain, which is accompanied by a film clip containing footage of the surgical procedure.
As the film explains, the woman, who lives in Arizona, first started to experience flu-like symptoms, followed by numbness in her left arm which grew progressively worse. Neurosurgeon Peter Nakaji operated, expecting to find a tumour in the brainstem, but instead found and removed a tapeworm.
It goes on to say that the woman was infected either by eating uncooked pork or unwashed food contaminated…
edyong | November 10, 2008If you're anything like me, then you will find that the onset of spring is a time of great rejoicing and equally great woe. The longer days, rising temperatures and greening world also signal the arrival of pollen, microscopic granules of hell determined to make you breathe fresh air only in the short spaces between sneezes, and enjoy the increasingly beautiful world through watery eyes.
But help is at hand. Allergens in the air can cause misery for about a third of people in Western countries, but a new clinical trial suggests that injecting allergens directly into someone's lymph nodes can…
edyong | November 6, 2008Specific language impairment (SLI) is a language disorder that affects growing children, who find it inexplicably difficult to pick up the spoken language skills that their peers acquire so effortlessly. Autism is another (perhaps more familiar) developmental disorder and many autistic children also have problems in picking up normal speech and communication. These two conditions have a common theme of language difficulties running through them, but a new study reveals a deeper connection - both are linked to a gene called CNTNAP2.
The story of CNTNAP2 actually begins with another gene,…