Posted on October 29, 2012  Comments (9)

Most of us want medical studies to provide clearer (more certain, more specific, more universal) indications than they actually provide. The conclusion of medical studies are often very clouded. Each person has a myriad of complex factors effecting how nutrition, activity and medication will affect us. Certain general conclusion can be drawn but it is very complex and difficult to universally state without various equivocations.

Advice For Diet Soda Lovers: Skip The Chips

I would like to know, with much greater certainty what nutritional and food related advice I need to consider when making my choices. To a significant degree I think there is going to be quite a bit of uncertainty (much more than we want) for at least the next 30 years (projecting far out into the future with any accuracy seems very difficult to me.

I am skeptical of purely correlational results. You can try to have similar subsets of people but that is actually hard and if you allow for similar groups and then let the choose something (like diet sodas or not) the chance of that actually being a significant choice that results in many other decisions being different between the subgroups seems a big risk (that makes accepting the correlation as evidence as risky). When you have a scientific explanation it makes the evidence much more compelling, but it is also easy to be taken in by explanations meant to fit the results of a study.

I can believe diet soda can do some bad things to your health. I believe if you are trying to reduce your weight by reducing calories drinking diet soda in place of sugary soda is a big help. I can believe drinking water instead of diet soda would be even better. I want caffeine and don’t like coffee. I have cut down drinking Mountain Dew to less than 2 a week. I have substituted diet soda over the last year. I am not sure that is the right choice, but it is the one I have made so far.

Related: Science Continues to Explore Causes of Weight Gain – Study Shows Weight Loss From Calorie Reduction Not Low Fat or Low Carb – Another Paper Questions Scientific Paper Accuracy – Contradictory Medical Studies

Posted on October 25, 2012  Comments (6)

There is another study showing the results of health studies often are proven false. Medical studies with striking results often prove false

The Stanford professor chose to publish this paper in a closed science publication. But previously he published openly on: Why Most Published Research Findings Are False.

Related: Majority of Clinical Trials Don’t Provide Meaningful Evidence – Statistical Errors in Medical Studies – Mistakes in Experimental Design and Interpretation – How to Deal with False Research Findings

Posted on October 17, 2012  Comments (2)

The Nobel Prize in Physiology or Medicine 2012 was awarded “for the discovery that mature cells can be reprogrammed to become pluripotent.” The prize goes jointly to Sir John B. Gurdon, Gurdon Institute in Cambridge, UK and Shinya Yamanaka, Kyoto University (he is also a senior investigator at the Gladstone Institutes in the USA).

The Nobel Prize recognizes two scientists who discovered that mature, specialised cells can be reprogrammed to become immature cells capable of developing into all tissues of the body. Their findings have revolutionised our understanding of how cells and organisms develop.

John B. Gurdon discovered (in 1962) that the specialisation of cells is reversible. In a classic experiment, he replaced the immature cell nucleus in an egg cell of a frog with the nucleus from a mature intestinal cell. This modified egg cell developed into a normal tadpole. The DNA of the mature cell still had all the information needed to develop all cells in the frog.

Shinya Yamanaka discovered more than 40 years later, in 2006, how intact mature cells in mice could be reprogrammed to become immature stem cells. Surprisingly, by introducing only a few genes, he could reprogram mature cells to become pluripotent stem cells, i.e. immature cells that are able to develop into all types of cells in the body.

These groundbreaking discoveries have completely changed our view of the development and cellular specialisation. We now understand that the mature cell does not have to be confined forever to its specialised state. Textbooks have been rewritten and new research fields have been established. By reprogramming human cells, scientists have created new opportunities to study diseases and develop methods for diagnosis and therapy.

All of us developed from fertilized egg cells. During the first days after conception, the embryo consists of immature cells, each of which is capable of developing into all the cell types that form the adult organism. Such cells are called pluripotent stem cells. With further development of the embryo, these cells give rise to nerve cells, muscle cells, liver cells and all other cell types – each of them specialised to carry out a specific task in the adult body. This journey from immature to specialised cell was previously considered to be unidirectional. It was thought that the cell changes in such a way during maturation that it would no longer be possible for it to return to an immature, pluripotent stage.

Related: 2011 Nobel Prize in Physiology or Medicine – Nobel Prize in Physiology or Medicine 2008 – 2012 Nobel Prize in Chemistry to Robert Lefkowitz and Brian Kobilka

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Posted on October 11, 2012  Comments (8)

The answer isn’t quite as simple as it seems. I find the wording in the video a bit confusing.

The point I believe, is that the sky is dark instead of light. But not that the brightness would be huge (so for example, you couldn’t necessarily read my book outside just by starlight). The light would be very faint, it is just that it would be lightish instead of blackish, due to the reasons explained (redshift etc.). At least that is my understanding.

Related: Why is it Colder at Higher Elevations? – Why Does the Moon Appear Larger on the Horizon? – Why is the Sky Blue? – Why Wasn’t the Earth Covered in Ice 4 Billion Years Ago – When the Sun was Dimmer

Posted on October 10, 2012  Comments (0)

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Chemistry for 2012 to

• Robert J. Lefkowitz, Howard Hughes Medical Institute and Duke University Medical Center, Durham, NC, USA
• and Brian K. Kobilka, Stanford University School of Medicine, Stanford, CA, USA

for studies of G-protein–coupled receptors.

Your body is a fine-tuned system of interactions between billions of cells. Each cell has tiny receptors that enable it to sense its environment, so it can adapt to new situtations. Robert Lefkowitz and Brian Kobilka are awarded the 2012 Nobel Prize in Chemistry for groundbreaking discoveries that reveal the inner workings of an important family of such receptors: G-protein–coupled receptors.

For a long time, it remained a mystery how cells could sense their environment. Scientists knew that hormones such as adrenalin had powerful effects: increasing blood pressure and making the heart beat faster. They suspected that cell surfaces contained some kind of recipient for hormones. But what these receptors actually consisted of and how they worked remained obscured for most of the 20th Century.

Lefkowitz started to use radioactivity in 1968 in order to trace cells’ receptors. He attached an iodine isotope to various hormones, and thanks to the radiation, he managed to unveil several receptors, among those a receptor for adrenalin: β-adrenergic receptor. His team of researchers extracted the receptor from its hiding place in the cell wall and gained an initial understanding of how it works.

The team achieved its next big step during the 1980s. The newly recruited Kobilka accepted the challenge to isolate the gene that codes for the β-adrenergic receptor from the gigantic human genome. His creative approach allowed him to attain his goal. When the researchers analyzed the gene, they discovered that the receptor was similar to one in the eye that captures light. They realized that there is a whole family of receptors that look alike and function in the same manner.

Today this family is referred to as G-protein–coupled receptors. About a thousand genes code for such receptors, for example, for light, flavour, odour, adrenalin, histamine, dopamine and serotonin. About half of all medications achieve their effect through G-protein–coupled receptors.

The studies by Lefkowitz and Kobilka are crucial for understanding how G-protein–coupled receptors function. Furthermore, in 2011, Kobilka achieved another break-through; he and his research team captured an image of the β-adrenergic receptor at the exact moment that it is activated by a hormone and sends a signal into the cell. This image is a molecular masterpiece – the result of decades of research.

Related: More details on the research – 2011 Nobel Prize in Chemistry – 2009 Nobel Prize in Chemistry: the Structure and Function of the Ribosome – The Nobel Prize in Chemistry 2008

Posted on October 9, 2012  Comments (6)

Quite a fun video. Frans de Waal shows us a task he gave Capuchin monkeys to see if they responded to a sense of fairness. See the rest of the talk.

Frans de Waal is a Dutch primatologist and ethologist. He is the Charles Howard Candler professor of Primate Behavior in the Emory University psychology department in Atlanta, Georgia. His research centers on primate social behavior, including conflict resolution, cooperation, inequity aversion, and food-sharing.

Related: Rats Show Empathy-driven Behavior – Capuchin Monkeys Using Stone Tools – Dolphin Delivers Deviously for Rewards – overpaid executives harm companies – Crow Using a Sequence of Three Tools

Posted on October 4, 2012  Comments (3)

Fish are hidden under the water so the unsustainable harvesting isn’t quite as obvious as the unsustainable government debt but they both are a result of us living beyond our sustainable production. You can live well by consuming past wealth and condemning your decedents to do without. That is the way we continue to live. Over-fishing a century ago was not as obviously dangerous as it is today. But we have witnessed many instances of overfishing devastating the fishing economy (when the fishing is unsustainable the inevitable result is collapse and elimination of the vast majority of the food and income that previous generations enjoyed).

The normal pattern has been to turn to more aggressive fishing methods and new technology to try and collect fish as over-fishing devastates yields. This, of course, further devastates the state of the resources and makes it so recovery will take much much longer (decades – or more).

New research shows the existing problems and the potential if we apply science and planning to manage fisheries effectively.

The over fishing problem is difficult because our nature is to ignore problems that are not immediate. But the costs of doing so are very large. If we don’t behave more wisely our children will pay the price. And, in fact, this problem is so acute now that those of us that expect to live a couple decades can expect to pay the price. In rich countries this will be tolerable, a bit less fish at much higher prices. In rich countries food prices are a minor expense compared to the billions of those not living in rich countries. They will suffer the most. As will those that have jobs directly dependent on fishing.

Related: Fishless Future – European Eels in Crisis After 95% Decline in Last 25 years – Let the Good Times Roll (using Credit) – SelFISHing – Running Out of Fish – The State of the Oceans is Not Good – Chinook Salmon Vanish Without a Trace

Posted on October 1, 2012  Comments (0)

2011 MacArthur Fellows

Elodie Ghedin (in video) is a biomedical researcher who is harnessing the power of genomic sequencing techniques to generate critical insights about human pathogens. A major focus of her work has been parasites that cause diseases endemic to tropical climates, such as leishmaniasis, sleeping sickness, Chagas disease, elephantiasis, and river blindness.

More scientists given the $500,000 award: Markus Greiner, Condensed Matter Physicist, Harvard University; Sarah Otto, Evolutionary Geneticist, University of British Columbia; Shwetak Patel, Sensor Technologist & Computer Scientist, University of Washington; Kevin Guskiewicz, Department of Exercise & Sport Science, University of North Carolina; Melanie Sanford, Organometallic Chemist, University of Michigan; Matthew Nock, Clinical Psychologist, Harvard University; Yukiko Yamashita, Developmental Biologist, University of Michigan; William Seeley, Neurologist, University of California, San Francisco.

Related: 2008 MacArthur Fellows – Presidential Early Career Awards for Scientists and Engineers – New Physics Prize Gives 9 Physicists $3 million Each – 2011 Nobel Prize in Chemistry