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In mythology, opening Pandora's Box released evil into the world instead, the Pandoravirus opens up a host of questions about the origins of life on Earth. Its discoverer, Jean-Michel Claverie at Aix-Marseille University in France , says: "We believe that those new Pandoraviruses have emerged from an ancestral cellular type that no longer exists."

Each virus is around 1 micrometre long and 0.5 micrometres across, and their respective genomes top out at 1.9 million and 2.5 million bases — making the viruses larger than many bacteria and even some eukaryotic cells. These viruses are more than mere record-breakers — they also hint at unknown parts of the tree of life. Just 7% of their genes match those in existing databases.

How did this odd cellular form turn into a virus? Chantal Abergel says it may have evolved as a survival strategy as modern cells took over. "On Earth it was winners and it was losers, and the losers could have escaped death by going through parasitism and then infect the winner," she says.

The method used to isolate theses viruses reminds me of an undergraduate virology experiment I used to carry out with students to isolate viruses from the environment.  Claverie and his team  scooped out sediment samples from the coast of Chile and a freshwater pond in Australia. They brought back the samples and placed them in a solution filled with antibiotics, to kill any bacteria that might have been along for the ride. Then they exposed the samples to their laboratory amoebas. "If they die, we suspect that there's something in there that killed them." he said. It worked - the infected amoebas spawned lots of Pandoraviruses.

The article appeared in the journal Science.

Microbes are everywhere and we are host to trillions -- many of them in our gut. These experiments illustrate how gut bacteria transplanted from mice that had received gastric bypass helped other mice lose weight too. Below is a summary of the research:

Obese people considering gastric bypass surgery to help trim their fat might one day have another option: swallowing a new supply of gut bacteria. A study in mice suggests that weight loss after bypass surgery is caused not by the operation itself, but at least in part by a change in the amounts of various species of microbes in the gut. A bypass operation separates off a small part of the stomach and connects that directly to the intestines. Recipients tend to feel less hungry, fill up more quickly and burn more calories at rest, and they often lose up to 75% of their excess fat. Counter-intuitively, this is thought to be caused by a change in metabolism, rather than by the reduced size of the stomach. Gut microbes are thought to be part of this picture. People who have had bypasses are known to experience changes in the selection of microbes in their guts. Fat people have been shown to host a different selection of gut bacteria from people who are obese, and transferring the gut bacteria of fat mice into thin ones can cause the thin mice to pack on extra weight. But no one knew whether the microbes in bypass patients changed because they got thin, or if the patients got thin because the microbes changed. To investigate, Lee Kaplan, director of the Obesity, Metabolism and Nutrition Institute at Massachusetts General Hospital in Boston, and his colleagues gave about a dozen obese mice bypass surgery. As expected, the mice lost about 29% of their body weight, and kept it off despite a high-fat diet. New conditions in their bodies — such as a change in bile acids — allowed a different set of gut bacteria to thrive. The results are promising for obesity treatments, but there are still hurdles to overcome. “You can’t just take a pill of the right bacteria and have them stick around,” says Seeley. If the gut’s environmental conditions don’t change, then the original microbes come back, he says. Kaplan says that the next steps are to isolate the four bacteria types that the study found to be at play and introduce them into obese mice or people. Antibiotic treatments might help the new bacteria to stick. “I believe it’s possible,” says Kaplan.

For the original article: click here

I watched this video some weeks ago and couldn't put it out of my mind, was it the slick infographics or the underlying message? The video was about the distribution of wealth in America, highlighting both the inequality and the difference between our perception of inequality and the actual numbers.

It would be interesting to do this on a global scale. History tells us that inequality in the distribution of wealth leads to social instability. Are we heading for a situation when the 99% have had enough?

Here is an absolutely amazing science video from NATURE

Scientists have come up with a way to make whole brains transparent, so they can be labelled with molecular markers and imaged using a light microscope. The technique, called CLARITY, enabled its creators to produce the detailed 3D visualisations you see in this video. It works in mouse brains and human brains; here the team use it to look into the brain of a 7-year-old boy who had autism.

Circular RNAs can act like molecular 'sponges' binding to and blocking tiny gene modulators called microRNAs. These circular RNA molecules comprise "a hidden parallel universe" of unexplored RNAs that control gene expression. Typical RNA-sequencing methods did not detect this molecules unless they had a molecular 'tail'.

Erik Sontheimer, a molecular biologist at Northwestern University in Evanston, Illinois said: “It’s yet another terrific example of an important RNA that has flown under the radar,” you just wonder when these surprises are going to stop.” Previous accounts of circular RNAs in plants and animals were generally dismissed as genetic accidents or experimental artefacts. Nikolaus Rajewsky, the lead author of one of the studies and a systems biologist at the Max Delbrück Center for Molecular Medicine in Berlin focused on a circular behemoth, some 1,500 nucleotides around, that is expressed in the brains of mice and humans. They found that it contains about 70 binding sites for a microRNA that can block gene expression linked to cancer and Parkinson’s disease.

Circular RNAs could also be sponges for microRNA from outside the cell, notes Rajewsky. Some have possible binding sites for viral microRNAs, which can subvert immune responses. He hypothesizes that circular RNA could even interact with RNA-binding proteins. “They are so abundant, there are probably a multitude of functional roles.”

This discovery goes further to illustrate that life is such a rich tapestry of interconnecting elements that it truly challenges our ability to fathom its complexity.

Reference: Nature vol: 494, pg 415 (28 February, 2013)

Elaine Hsiao talks about her work at Caltech on how the microbes in your gut affects your brain and your behaviour. She uncovered the role for the commensal microbiota (the gut microbes) in regulating autism-related behaviours and metabolism. She is currently studying the mechanisms by which microbes affect host production of neuroactive molecules (like serotonin) and how they influence health and disease. The microbial gut transplant with happy bacteria is a step closer!


Aubrey de Grey, a British researcher on aging, has drawn a roadmap of how we can defeat biological aging.

Normal metabolism leads to cell damage -- the goal of Gerontology is to prevent the damage before it happens. Geriatric medicine is about ameliorating the pathology of the damage.

cell-damage-1The focus of damage control is on the long-lived molecules. Also there is possible control of genes by the FOXO protein -- the activation of the latent ability of the cell for self-repair.

Cell-damage-2Using a mouse model some of the targets for damage control have been successful.


For more here is Aubrey ...

As Christmas approaches there will be a vast selection of mobile devices on offer to tempt the unsuspecting buyer, Therefore it might be useful to read the article from Business Insider entitled: 'The Future of Digital', at  http://read.bi/Rlnn5S

There are only two platforms, Android and iPad and only two smartphone players -- Apple and Samsung.

As far as apps go, there is only Apple.

When the printing press became available  it was first used for printing erotic novels, then 150 years later for scientific journals -- likewise with the Internet -- first pornography -- then democracy?

Using Internet technologies such as peer-to-peer sharing, wireless, software for social creation, and open-source development will enable new kinds of cooperative structures to flourish as a way of getting things done in business, science, as an alternative to centralized and institutional structures.

For more watch Clay Shirky's TED Talk.


How is your KLOUT? I am reminded of a saying attributed to Einstein although it was probably just a sign he had hanging in his office:

Not everything that counts can be counted, and not everything that can be counted counts.

KLOUT is a measure of your Twitter and Facebook activity and you can find your score by going to their website. I am proud to say that my score is low: about 20 -- if your score is >50, you should seriously think about "getting a life". Many of us have different presences on the web and KLOUT doesn't measure or aggregate these.

If you are really obsessed by KLOUT, you can buy Twitter followers….. and improve your score!