Woman of 24 found to have no cerebellum in her brain
DON’T mind the gap. A woman has reached the age of 24 without anyone realising she was missing a large part of her brain. The case highlights just how adaptable the organ is. The discovery was made when the woman was admitted to the Chinese PLA General Hospital of Jinan Military Area Command in Shandong Province complaining of dizziness and nausea. She told doctors she’d had problems walking steadily for most of her life, and her mother reported that she hadn’t walked until she was 7 and that her speech only became intelligible at the age of 6. Doctors did a CAT scan and immediately identified the source of the problem – her entire cerebellum was missing (see scan, below left). The space where it should be was empty of tissue. Instead it was filled with cerebrospinal fluid, which cushions the brain and provides defence against disease. The cerebellum – sometimes known as the “little brain” – is located underneath the two hemispheres. It looks different from the rest of the brain because it consists of much smaller and more compact folds of tissue. It represents about 10 per cent of the brain’s total volume but contains 50 per cent of its neurons. Although it is not unheard of to have part of your brain missing, either congenitally or from surgery, the woman joins an elite club of just nine people who are known to have lived without their entire cerebellum. A detailed description of how the disorder affects a living adult is almost non-existent, say doctors from the Chinese hospital, because most people with the condition die at a young age and the problem is only discovered on autopsy (Brain, doi.org/vh7). (via Woman of 24 found to have no cerebellum in her brain - health - 10 September 2014 - New Scientist)
John Wilkins - Philosophy of Evolutionary Biology
The philosophy of biology is a subfield of philosophy of science, which deals with epistemological, metaphysical, and ethical issues in the biological and biomedical sciences. Although philosophers of science and philosophers generally have long been interested in biology (e.g., Aristotle, Descartes, and even Kant), philosophy of biology only emerged as an independent field of philosophy in the 1960s and 1970s. Philosophers of science then began paying increasing attention to biology, from the rise of Neodarwinism in the 1930s and 1940s to the discovery of the structure of DNA in 1953 to more recent advances in genetic engineering. Other key ideas include the reduction of all life processes to biochemical reactions, and the incorporation of psychology into a broader neuroscien
“When the internet arrived, it seemed to promise a liberation from the boredom of industrial society, a psychedelic jet-spray of information into every otherwise tedious corner of our lives. In fact, at its best, it is something else: a remarkable helper in the search for meaningful connections. But if the deep roots of boredom are in a lack of meaning, rather than a shortage of stimuli, and if there is a subtle, multilayered process by which information can give rise to meaning, then the constant flow of information to which we are becoming habituated cannot deliver on such a promise. At best, it allows us to distract ourselves with the potentially endless deferral of clicking from one link to another. Yet sooner or later we wash up downstream in some far corner of the web, wondering where the time went. The experience of being carried on these currents is quite different to the patient, unpredictable process that leads towards meaning.”
“Information is perhaps the rawest material in the process out of which we arrive at meaning: an undifferentiated stream of sense and nonsense in which we go fishing for facts. But the journey from information to meaning involves more than simply filtering the signal from the noise. It is an alchemical transformation, always surprising. It takes skill, time and effort, practice and patience. No matter how experienced we become, success cannot be guaranteed. In most human societies, there have been specialists in this skill, yet it can never be the monopoly of experts, for it is also a very basic, deeply human activity, essential to our survival. If boredom has become a sickness in modern societies, this is because the knack of finding meaning is harder to come by.”
First ban on shark and manta ray trade comes into force
All trade in five named species of sharks is to be regulated from now on, in a significant step forward for conservation.
Without a permit confirming that these sharks have been harvested legally and sustainably, the sale of their meat or fins will be banned. The regulation was agreed last year at a meeting of the Convention on International Trade in Endangered Species (Cites) in Thailand. The rules also apply to manta rays. Shark numbers have been under severe pressure in recent years as the numbers killed for their fins soared. Scientific estimates put the number at about 100m a year, with demand driven by the fin soup trade in Hong Kong and China. Campaigners have been seeking to stop the unregulated trade in sharks since the 1990s but it was only at the Cites meeting in Bangkok last year that they finally managed to achieve sufficient votes to drive through the ban. From Sunday, the oceanic whitetip, the porbeagle and three varieties of hammerhead will be elevated to Appendix II of the Cites code, which means that traders must have permits and certificates. Manta rays, valued for their gills which are used in Chinese medicine, will also be protected. The survival of all these species has been threatened by over fishing. (via BBC News - First ban on shark and manta ray trade comes into force)
Evolution’s Random Paths Lead to One Place
See on Scoop.it - The future of medicine and health
A massive statistical study suggests that the final evolutionary outcome — fitness — is predictable.
In his fourth-floor lab at Harvard University, Michael Desai has created hundreds of identical worlds in order to watch evolution at work. Each of his meticulously controlled environments is home to a separate strain of baker’s yeast. Every 12 hours, Desai’s robot assistants pluck out the fastest-growing yeast in each world — selecting the fittest to live on — and discard the rest. Desai then monitors the strains as they evolve over the course of 500 generations. His experiment, which other scientists say is unprecedented in scale, seeks to gain insight into a question that has long bedeviled biologists: If we could start the world over again, would life evolve the same way? Many biologists argue that it would not, that chance mutations early in the evolutionary journey of a species will profoundly influence its fate. “If you replay the tape of life, you might have one initial mutation that takes you in a totally different direction,” Desai said, paraphrasing an idea first put forth by the biologist Stephen Jay Gould in the 1980s. Desai’s yeast cells call this belief into question. According to results published in Science in June, all of Desai’s yeast varieties arrived at roughly the same evolutionary endpoint (as measured by their ability to grow under specific lab conditions) regardless of which precise genetic path each strain took. It’s as if 100 New York City taxis agreed to take separate highways in a race to the Pacific Ocean, and 50 hours later they all converged at the Santa Monica pier. The findings also suggest a disconnect between evolution at the genetic level and at the level of the whole organism. Genetic mutations occur mostly at random, yet the sum of these aimless changes somehow creates a predictable pattern. The distinction could prove valuable, as much genetics research has focused on the impact of mutations in individual genes. For example, researchers often ask how a single mutation might affect a microbe’s tolerance for toxins, or a human’s risk for a disease. But if Desai’s findings hold true in other organisms, they could suggest that it’s equally important to examine how large numbers of individual genetic changes work in concert over time. “There’s a kind of tension in evolutionary biology between thinking about individual genes and the potential for evolution to change the whole organism,” said Michael Travisano, a biologist at the University of Minnesota. “All of biology has been focused on the importance of individual genes for the last 30 years, but the big take-home message of this study is that’s not necessarily important.” (via Yeast Study Suggests Genetics Are Random but Evolution Is Not | Simons Foundation)
I wrote a story recently about a cool technique called optogenetics, developed by bioengineering professor Karl Deisseroth, MD, PhD. He won the Keio Prize in Medicine, and I thought it might be interesting to talk with some other neuroscientists at Stanford to get their take on the importance of the technology. You know something is truly groundbreaking when each and every person you interview uses the word “revolutionary” to describe it.
Optogenetics is a technique that allows scientists to use light to turn particular nerves on or off. In the process, they’re learning new things about how the brain works and about diseases and mental health conditions like Parkinson’s disease, addiction and depression.
In describing the award, the Keio Prize committee wrote:
By making optogenetics a reality and leading this new field, Dr. Deisseroth has made enormous contributions towards the fundamental understanding of brain functions in health and disease.
One of the things I found most interesting when writing the story came from a piece Deisseroth wrote several years ago in Scientific American in which he stressed the importance of basic research. Optogenetics would not have been a reality without discoveries made in the lowly algae that makes up pond scum.
“The more directed and targeted research becomes, the more likely we are to slow our progress, and the more certain it is that the distant and untraveled realms, where truly disruptive ideas can arise, will be utterly cut off from our common scientific journey,” Deisseroth wrote.
Deisseroth told me that we need to be funding basic, curiosity-driven research along with efforts to make those discoveries relevant. He said that kind of translation is part of the value of programs like Stanford Bio-X – an interdisciplinary institute founded in 1998 – which puts diverse faculty members side by side to enable that translation from basic science to medical discovery.
See on scopeblog.stanford.edu