Medicine & Health
neurophilosophy | June 16, 2010THE dangers of obesity are very well known. Being overweight is associated with an increased risk of coronary heart disease and stroke, the two leading causes of death in the Western world. Gout is more common in overweight people, with the risk of developing the condition increasing in parallel with body weight. Obese people are twice as likely to develop type 2 diabetes as those who are not overweight, and being overweight is also associated with several types of cancer. The list goes on...
Less well known is the effect of obesity on the brain. In the past few years, however, it has…
edyong | March 11, 2010Not Exactly Pocket Science is a set of shorter write-ups on new stories with links to more detailed takes by the world's best journalists and bloggers. It is meant to complement the usual fare of detailed pieces that are typical for this blog.
Geneticist sequences own genome, finds genetic cause of his disease
If you've got an inherited disease and you want to find the genetic faults responsible, it certainly helps if you're a prominent geneticist. James Lupski (right) from the Baylor College of Medicine suffers from an incurable condition called Charcot-Marie-Tooth (CMT) disease, which…
edyong | March 7, 2010Sex might be fun but it's not without risks. As your partner exposes themselves to you, they also expose you to whatever bacteria, viruses or parasites they might be carrying. But some animals have a way around that. Ekaterina Litvinova has found that when male mice get a whiff of female odours, their immune systems prepare their airways for attack, increasing their resistance to flu viruses.
Litvinova worked with a group of mice that were exposed to bedding that had previously been soiled by females in the sexually receptive parts of their cycle. She compared them to a second more monastic…
edyong | March 5, 2010The Not Exactly Pocket Science experiment continues after the vast majority of people who commented liked the pilot post. I'm really enjoying this, for quite unexpected reasons. It's forcing me to flex writing muscles that usually don't get much of a workout. Writing short pieces means being far more economical with language and detail than usual. It means packing in as much information as possible while still keeping things readable. And it means blitz-reading papers and writing quickly without losing any accuracy.
One quick note before the good stuff: last time, a few people suggested that…
edyong | March 4, 2010We've all heard about "beer goggles", the mythical, invisible eyewear that makes everyone else seem incredibly attractive after a few pints too many. If only beer had the reverse effect, making the drinker seem irresistibly attractive. Well, the good news is that beer does actually do this. The bad news is that the ones who are attracted are malarial mosquitoes.
Anopheles gambiae (the mosquito that transmits malaria) tracks its victims by their smells. By wafting the aromas of humans over thousands of mosquitoes, Thierry Lefevre found that they find the body odour of beer drinkers to be…
edyong | March 3, 2010You are outnumbered by a factor of 10 to one, by forces you cannot see. Your body has around ten trillion cells, but it's also home to a hundred trillion bacteria. For every gene in your genome, there are 100 bacterial ones. Most of these are found the dark, dank environment of your bowel but their incredible diversity is being brought to the surface. Say hello to the gut metagenome.
Together with a team of international scientists, Junjie Qin and Ruiqiang Li from BGI-Shenzen had the unenviable task of studying the bacteria from the faeces of 124 Europeans. They used a formidable and…
edyong | February 15, 2010The social interactions that come naturally to most people are difficult for people with autism and Asperger syndrome. Simple matters like making eye contact, reading expressions and working out what someone else is thinking can be big challenges, even for "high-functioning" and intelligent individuals. Now, a preliminary study of 13 people suggests that some of these social difficulties could be temporarily relieved by inhaling a hormone called oxytocin.
The participants, who either had Asperger or high-functioning autism, experienced stronger feelings of trust, showed stronger social…
edyong | February 14, 2010
Millions of people in Latin America have been invade by a parasite - a trypanosome called Trypanosome cruzi. They are passed on through the bite of the blood-sucking assassin bug and they cause Chagas disease, a potentially fatal illness that affects the heart and digestive system. The infections are long-lasting; it can take decades for symptoms to show and a third of infected people eventually die from the disease. But T.cruzi does much more than invade our flesh and blood; it also infiltrates our genomes.
T.cruzi is unusual in that a massive proportion of its DNA, around 15-30%, lies…
edyong | December 31, 2009If you search for decent definitions of evolution, the chances are that you'll see genes mentioned somewhere. The American Heritage Dictionary talks about natural selection acting on "genetic variation", Wikipedia discusses "change in the genetic material of a population... through successive generations", and TalkOrigins talks about changes that are inherited "via the genetic material". But, as the Year of Darwin draws to a close, a new study suggests that all of these definitions are too narrow.
Jiali Li from the Scripps Institute in Florida has found that prions - the infectious proteins…
edyong | December 29, 2009Many of us have just spent the Christmas season with a persistent and irritating ringing noise in our ears. But now that the relatives have gone home for the year, it's worth remembering that a large proportion of the population suffers from a more persistent ringing sensation - tinnitus. It happens in the absence of noise, it's one of the most common symptoms of hearing disorders, and it's loud enough to affect the quality of life of around 1-3% of the population.
There have been many suggested treatments but none of them have become firmly established and most simply try to help people…
edyong | December 24, 2009This is an updated version of the first post I wrote this year. The scientists in question were looking at ways of recruiting bacteria in the fight against mosquito-borne diseases, such as dengue fever. They've just published new results that expand on their earlier experiments.
Mosquitoes are incredibly successful parasites and cause millions of human deaths every year through the infections they spread. But they are no match for the most successful parasite of all - a bacterium called Wolbachia. It infects around 60% of the world's insect species and it could be our newest recruit in the…
edyong | December 10, 2009This is Round Three of the NERS Stories of the Year Reader's Poll. In an attempt to find the most interesting posts on this blog over the last year (leave me the illusion that there were some), I'm doing a series of nine polls, each focused on a specific field of science. So far, we've had animal behaviour and palaeontology. Today, medicine.
Here's your selection:
Rapamycin - the Easter Island drug that extends lifespan of old mice
From Spanish to swine - how H1N1 kicked off a 91-year pandemic era
Fishing expedition reveals unexpected link between Alzheimer's and prion diseases
Genome…
edyong | December 2, 2009If I say the phrases 'anti-ageing' and 'nutritional balance' to you, you'd probably think of the pages of quack websites selling untested supplements than the pages of Nature. And yet this week's issue has a study that actually looks at these issues with scientific rigour. It shows that, at least for fruit flies, eating a diet with just the right balance of nutrients can lengthen life without the pesky drawback of producing fewer offspring.
Despite the claims of the cosmetic and nutritional industries, chemicals or techniques that slow the ageing process are few and far between. We're a long…
edyong | November 30, 2009This article is reposted from the old Wordpress incarnation of Not Exactly Rocket Science.
Attention-deficit hyperactivity disorder is the most common developmental disorder in children, affecting anywhere between 3-5% of the world's school-going population. As the name suggests, kids with ADHD are hyperactive and easily distracted; they are also forgetful and find it difficult to control their own impulses.
While some evidence has suggested that ADHD brains develop in fundamentally different ways to typical ones, other results have argued that they are just the result of a delay in the…
edyong | November 3, 2009A friend of mine recently got onto a train and found a group of four seats that were empty except for one woman who was sitting face down. She looked asleep and he looked forward to a quiet journey. As soon as he sat down, the woman lifted her head to reveal streaming, puffy eyes and started sneezing profusely. This happened a few weeks after swine flu first began to dominate the headlines but being English, he was bound to the socially awkward choice of staying in his seat for the sake of avoiding social awkwardness.
Many of us probably have similar stories. At a time when fears of a flu…
edyong | October 26, 2009The prospect of infections spreading from animals to humans has become all too real with the onset of the current swine flu pandemic, and the threat of a bird flu still looming. But infections can jump the other way too. Decades before the world's media were gripped with panic over bird flu, humans transferred a disease to chickens and it has since caused a poultry pandemic right under our noses.
The infection in question is a familiar one - Staphylococcus aureus, a common human bacterium that's behind everything from mild skin infections to life-threatening MRSA. It causes chicken…
edyong | October 20, 2009This is the story of a Turkish boy, who became the first person to have a genetic disorder diagnosed by thoroughly sequencing his genome. He is known only through his medical case notes as GIT 264-1 but for the purposes of this tale, I'm going to call Baby T.
At a mere five months of age, Baby T was brought to hospital dehydrated and in poor health. In some ways, this wasn't surprising. His parents were blood relatives and they had suffered through two miscarriages and the death of one premature baby. Baby T himself was born prematurely at 30 weeks.
Baby T's family history suggested that he…
neurophilosophy | October 16, 2009THINKING of and saying a word is something that most of us do effortlessly many times a day. This involves a number of steps - we must select the appropriate word, decide on the proper tense, and also pronounce it correctly. The neural computations underlying these tasks are highly complex, and whether the brain performs them all at the same time, or one after the other, has been a subject of debate.
This debate has now apparently been settled, by a team of American researchers who had the rare opportunity to investigate language processing in conscious epileptic patients undergoing surgery…
edyong | October 15, 2009The placebo effect - the phenomenon where fake medicines sometimes work if a patient believes that they should - is a boon to quacks the world over. Why it happens is still a medical mystery but thanks to a new study, we have confirmation that the spine is involved.
Frank Eippert from the University Medical Center Hamburg-Eppendorf used a technique caled functional magnetic resonance imaging (fMRI) to scan the backbones of volunteers as they experienced the placebo effect. Eippert heated the recruits' forearms to the point of pain and he gave them cream to soothe the sting. The creams were…
edyong | October 8, 2009Chronic fatigue syndrome (CFS) is a disease that afflicts people with extreme and debilitating tiredness that lasts for many years and isn't relieved by rest. Some estimates suggest that it affects up to 1% of the world's population. We don't know what causes it. Prostate cancer is one of the most common cancers in the world and kills around 221,000 people every year. Its causes too are largely unknown. What do these two diseases have in common? They have both been recently linked to a virus called XMRV (or xenotropic MulV-related virus in full).
This doesn't mean that you can 'catch' either…