Medicine & Health
edyong | November 1, 2008
In the heart of Bolivia, an Amazonian society is losing its traditional knowledge of the medicinal value of local plants, to the detriment of its children's health. The Tsimane' are a small seven thousand-strong population living in a lowland region of Bolivia, who possess tremendous knowledge about the plants they share their forest with.
Their botanical know-how trickles down through the generations and allows them to use the local plant-life for construction, tool-making, medicine and food. These plants account for over half of their household consumption of goods, while those…
edyong | October 23, 2008
The plague, or the Black Death, is caused by a microbe called Yersinia pestis. In the 14th century, this microscopic enemy killed off a third of Europe's population. While many people consign the plague to centuries past, this attitude is a complacent one. Outbreaks have happened in Asia and Africa over the last decade and the plague is now recognised as a re-emerging disease. In 1996, two drug-resistant strains of plague were isolated from Madagascar. One of these, was completely resistant to all the drugs that are used to control outbreaks.
Anyone interested in bacteria can attest to…
edyong | October 21, 2008
Fighting malaria with mosquitoes seems like an bizarrely ironic strategy but it's exactly what many scientists are trying to do. Malaria kills one to three million people every year, most of whom are children. Many strategies for controlling it naturally focus on ways of killing the mosquitoes that spread it, stopping them from biting humans, or getting rid of their breeding grounds.
But the mosquitoes themselves are not the real problem. They are merely carriers for the true cause of malaria - a parasite called Plasmodium. It suits neither mosquitoes nor humans to be infected with…
neurophilosophy | October 12, 2008The BBC has film footage of the legendary Bluegrass musician Eddie Adcock playing the banjo whilst having his brain operated on.
Adcock is suffering from essential tremor, a progressive neurological condition characterised by tremors in the arms which appear during voluntary movements and which are thought to occur as a result of degeneration of cerebellar Purkinje cells.
The film shows neurosurgeons at Vanderbilt University Medical Center in Nashville, Tennessee treating Adcock with deep brain stimulation (DBS), in which electrodes are implanted into the thalamus. Together with the…
edyong | October 9, 2008
Throughout the day, our skins are constantly sending out messages that we are completely oblivious to. The message is written in chemical form and it says, "Here I am. Come and get me". We neither see nor hear these signals but other creatures do, and they slither, crawl and swim our way in response.
These creatures are nematodes, a group of worms that are some of the most common animals on the planet. The vast majority of nematode species are parasites, and hundreds of species count humans among their potential hosts. In the developing countries of the tropics and sub-tropics, parasitic…
edyong | October 7, 2008
It is the instinct of every mother to protect their children as they grow up, shielding them from the dangers of the outside world. Right from birth, life can be a difficult experience. Within a few hours, the child is sent from a safe, warm, constantly-nourished cocoon into a bright, noisy and threatening world. This stressful transition poses a serious threat to the newborn's vulnerable and still-developing mind. But new research has shown that even in these first vital hours, mothers are already inadvertently protecting their children - by shutting down their brain cells.
In foetuses…
edyong | October 6, 2008
There is a widespread belief, that being overweight or obese is a question of failing willpower, fuelled in no small part by food, fitness and beauty industries. But if we look at the issue of obesity through a scientific spyglass, a very different picture emerges. Genes, for example, exert a large influence on our tendency to become obese often by influencing behaviour - a case of nature via nurture. But it's not just our own genes that are important.
In terms of processing food, humans are hardly self-sufficient. Our guts are the home of trillions of bacteria that help to break down…
neurophilosophy | October 1, 2008These X-rays show a knife plunged into the skull of a 16-year-old boy from southeast London. Fortunately, his injuries were nowhere near as serious as they might have been - according to a police officer quoted in The Times, "the blade was a kitchen knife and because of that it was flexible and went around the bone." He has, however, started walking with a limp, and his reaction times have slowed.
Related:
Unusual penetrating brain injuries
The incredible case of Phineas Gage
neurophilosophy | September 25, 2008Radiation therapy is a common treatment for adults and children who present with tumours in or close to the brain. In the last 20 years, advances in radiotherapy have significantly improved the prognosis for brain cancer patients. However, the resulting longer survival rates reveal that the therapy has deleterious effects on brain health - even at low doses, radiation leads to cognitive impairments in later life.
These impairments, which include attention deficits and learning disabilities, occur as a result of the effects of radiation on the hippocampus. This structure is known to be…
neurophilosophy | August 27, 2008The patient lies on the operating table, with the right side of his body raised slightly. The anaesthetist sterilizes his scalp and injects it with Nupercaine to produce analgesia - the patient will remain fully conscious throughout the procedure. Behind the surgical drapes, three large incisions are made in his scalp. A large flap of bone is then cut from his skull, and turned downward to expose the surface of his brain. The ultraviolet lights which illuminate the operating theatre and keep the air sterile are positioned in such a way that they do not shine directly upon the cortex.
Using an…
neurophilosophy | August 27, 2008At Bioephemera, Jessica has a fascinating post about depictions of madness in 15th-17th century art, during which time mental illness was popularly attributed to the presence of a "stone of madness" (or "stone of folly") in the head.
One of the earliest depictions of this is found in the above painting, Hieronymous Bosch's The Cure of Folly (The Extraction of the Stone of Madness), and similar scenes were subsequently depicted by other Renaissance artists.
As Jessica explains, historians of art and medicine are in dispute about the underlying meaning of the paintings. Were they depictions…
neurophilosophy | August 26, 2008Former British Prime Minister Margaret Thatcher has dementia.
In her forthcoming book, which is serialized in the Mail on Sunday (a paper which, I hasten to add, I do not read), Carol Thatcher reveals that her mother's mental faculties have been in decline for the past 7 years:
When she learned Latin at school, she absorbed the vocabulary and declensions with her blotting-paper brain. It was a skill honed to perfection during her chemistry degree at Oxford, when scientific equations added yet another dimension to an already orderly mind.
...
Whereas previously you would never have had to…
neurophilosophy | August 24, 2008The BBC has produced an interesting series called Blood and Guts about the modern history of surgery and the first episode, which is about neurosurgery, is now available online at the BBC iPlayer website. (For those outside the U.K., it is also available as a torrent.)
Presented by surgeon Michael Mosley, the program begins with the pioneering work of Harvey Cushing, then continues with a discussion of Phineas Gage, the Yale physiologist Jose Delgado and the lobotomist Walter Freeman. Mosley also meets Howard Dully, who was lobotomized at the age of 12 by Freeman.
In one particularly…
neurophilosophy | August 22, 2008Stroke can be extremely debilitating, but if the damage is not too severe, and appropriate rehabilitation is administered, the brain can reorganize itself to compensate for the loss of function. This reorganization can occur because the brain remains 'plastic' throughout life; it leads to recovery, but can also have unexpected consequences.
Something very unexpected happened to Ken Walters, a 51-year-old former engineer from Lancashire, following his cerebrovascular accident. According to the Daily Mail, Walters suffered a "mild stroke" (possibly a transient ischaemic attack) in 2005, and…
neurophilosophy | August 22, 2008Harvey Cushing (1869-1939) is considered to be the father of modern neurological surgery. In the early part of the 20th century, he developed basic techniques and instruments for operating on the brain and, as a result, founded the discipline as a distinct surgical speciality. Before Cushing began his career, brain tumours were considered to be inoperable, and the mortality rate for any surgical procedure which involved opening the skull was around 90%. Early in his career, Cushing dramatically reduced the mortality rate for neurosurgery to less than 10%, and by the time of his retirement in…
neurophilosophy | August 22, 2008This advertisement for Ritalin comes from a 1966 issue of the Journal of the American Medical Association (JAMA). Ritalin, or methylphenidate, is widely - and controversially - prescribed to children with attention deficit hyperactivity disorder.
The drug is an amphetamine-like stimulant which blocks reuptake of the neurotransmitters dopamine and noradrenaline (norepinephrine) in the prefrontal cortex. This seems paradoxical given that it improves concentration and reduces impulsivity in hyperactive children, and exactly why it is an effective treatment for ADHD is still unclear.
In the…
edyong | August 18, 2008People in most parts of the world are living longer and longer, thanks to great leaps in medicine and sanitation over the last century. But these growing life expectancies bring with them a sense of unease. The biggest worry is the possibility that medical advances are artificially prolonging life with little regard for its quality. Old age, after all, brings with it an increased risk of chronic diseases such as cancer, as well as both physical and mental decline.
This is not just a moral question, but an economic one too. The "oldest-old" are the fastest growing demographic in Western…
edyong | August 17, 2008They say that memory declines as age marches on, but that only applies to neurons - the immune system has a very different sort of memory and it stays fresh till the end of life. To this day, people who survived the 1918 flu pandemic carry antibodies that can remember and neutralise the murderous strain.
The 1918 influenza virus was the most devastating infections of recent history and killed anywhere from 20 to 100 million people in the space of two years. Ironically, it seems that the virus killed via the immune system of those infected. It caused immune cells to unleash a torrent of…
edyong | August 16, 2008
Imagine reading the paper to find that a new wonder drug has been created that could save your life, if only you could afford it. Alternatively, put yourself in the shoes of the authorities that must decide not to offer powerful new drugs on the NHS because they simply aren't cost-effective enough. These situations are all too common-place and are often due to the extremely high costs of drug development. But a couple of years ago, scientists at Icon Genetics and Bayer Bioscience made an exciting step toward lowering these costs for some of the most promising new treatments.
The…
neurophilosophy | August 7, 2008The use of improvised explosive devices (IEDs, or roadside bombs) has led to an increase in the numbers of troops sustaining traumatic brain injury during military service in Afghanistan and Iraq. Such injuries are caused by the high pressure shock waves generated by the explosions, which cause rapid head movements, such that the brain is sheared and torn as it comes into contact with the inside of the skull.
Whereas conventional traumatic brain injuries caused by penetrative head wounds are easily diagnosed, those who sustain this kind of closed head injury often exhibit no external wounds…