Our most traumatic memories could be erased, thanks to the marine snail

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Our most traumatic memories could be erased, thanks to the marine snail

Alasdair Wilkins — Although the idea of erasing your memories may sound horrific, there may be nothing better for those dealing with severe trauma. Now we’re one step closer to making it a reality, with a little help from the tiny marine snail.

UCLA researcher David Glanzman led the study, which discovered that it’s possible to erase long-term memories in snails by inhibiting a specific protein kinase known as PKM. While researchers have previously made headway with memory-erasing drugs, this new work focuses on the actual neurons of the brain, potentially allowing far finer control over the memory erasure process. If the methods used here could be adapted to humans, Glanzman hopes it could be used to help treat severe post-traumatic stress disorder, drug addiction, and possible long-term memory disorders such as Alzheimer’s.

Glanzman explains how it all works:

“Almost all the processes that are involved in memory in the snail also have been shown to be involved in memory in the brains of mammals. We found that if we inhibit PKM in the marine snail, we will erase the memory for long-term sensitization. In addition, we can erase the long-term change at a single synapse that underlies long-term memory in the snail.”

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via Our most traumatic memories could be erased, thanks to the marine snail.

Many negative behaviors, I think, can be attributed to bad memories. You can reprogram your bad memories, because the way memory works, you only remember the last time you remembered something. You don’t remember the actual event. You rebuild your memories every time you remember them.

Reprogramming takes time … although if you do it in lucid dreams, you might reclaim the lost 1/3rd of your life as well as making your waking life better. I’d like to be able to get into my head and switch off a few things, make it as if they never happened. … with the option to switch them back on later.

Here’s how. Step 1: Start having lucid dreams. Step 2: Meditate and cultivate your objective observer. Step 3: Observe your dream as you dream. If fun stuff happens, enjoy it. If anything bad happens, take the opportunity to solve the problem. It’s your world in the dream, so create a solution and see how it feels.

Squids In Space–Seriously

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The last flight of the space shuttle Endeavor will be both manned and squidded.

The most famous science experiment on board, of course, will be the Alpha Magnetic Spectrometer, which will set up shop at the ISS to measure cosmic rays, dusting for the fingerprints of dark matter and antimatter. So that’s cool. But is it as cool as baby squid in space?

…why exactly would you want to put squids in space? I mean, besides the cool factor, what is there to be gained? I did a little more poking around, and, bless the internet, there’s a webpage on the project. It turns out that the particular species of squid to be shipped off-planet is our old friend the bobtail squid.

What makes this squid unique is its light organ, which glows at night and hides its shadow from prey lurking underneath. The light is powered by a particular bioluminescent bacteria (Vibrio fishceri) that the squid draws in from the surrounding water. Every day it expels the old bacteria and takes in a new batch. Newly born squid can’t produce the light, but within several hours they become bioluminescent as they take in the bacteria. This development gives scientists a close look at morphogenesis, which is the biological process that causes an organism to develop its shape—one of the fundamentals of development biology. The squid experiment came about when Ned [faculty sponsor] learned about the work of Dr. Jamie S. Foster at the University of Florida in Gainesville. Dr. Foster’s work is focused on what happens to this morphogenesis process under micro-gravity conditions.

A-ha! So the real question is morphogenesis under micro-gravity, or, what is the effect of gravity on how an organism makes its shape? And the squid/bacteria symbiosis happens to be a good model system to answer this question.

If you’re having a hard time making that connection, it’s because a critical piece of information was omitted from the otherwise excellent summary above. That is, when a newly born squid takes in the bacteria that it needs to produce light, those bacteria induce an serious physical restructuring of the squid’s body so that it can host them appropriately. The baby squid actually changes shape as a result of taking in bacteria.

Which is a pretty wild thing to study all by itself, on Earth, but when you decide to study it in space . . . whoa.

via Squids In Space–Seriously.

>Curse of the Pharaoh’s DNA

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Mummies found in King Tutankhamun’s tomb are at the centre of a dispute over DNA analysis.

Jo Marchant  – Some researchers claim to have analysed DNA from Egyptian mummies. Others say that’s impossible. Could new sequencing methods bridge the divide?

Cameras roll as ancient-DNA experts Carsten Pusch and Albert Zink scrutinize a row of coloured peaks on their computer screen. There is a dramatic pause. “My god!” whispers Pusch, the words muffled by his surgical mask. Then the two hug and shake hands, accompanied by the laughter and applause of their Egyptian colleagues. They have every right to be pleased with themselves. After months of painstaking work, they have finally completed their analysis of 3,300-year-old DNA from the mummy of King Tutankhamun.

Featured in the Discovery Channel documentary King Tut Unwrapped last year and published in the Journal of the American Medical Association (JAMA)1, their analysis — of Tutankhamun and ten of his relatives — was the latest in a string of studies reporting the analysis of DNA from ancient Egyptian mummies. Apparently revealing the mummies’ family relationships as well as their afflictions, such as tuberculosis and malaria, the work seems to be providing unprecedented insight into the lives and health of ancient Egyptians and is ushering in a new era of ‘molecular Egyptology’. Except that half of the researchers in the field challenge every word of it.

Enter the world of ancient Egyptian DNA and you are asked to choose between two alternate realities: one in which DNA analysis is routine, and the other in which it is impossible. “The ancient-DNA field is split absolutely in half,” says Tom Gilbert, who heads two research groups at the Center for GeoGenetics in Copenhagen, one of the world’s foremost ancient-DNA labs.

Unable to resolve their differences, the two sides publish in different journals, attend different conferences and refer to each other as ‘believers’ and ‘sceptics’ — when, that is, they’re not simply ignoring each other. The Tutankhamun study reignited long-standing tensions between the two camps, with sceptics claiming that in this study, as in most others, the results can be explained by contamination. Next-generation sequencing techniques, however, may soon be able to resolve the split once and for all by making it easier to sequence ancient, degraded DNA. But for now, Zink says, “It’s like a religious thing. If our papers are reviewed by one of the other groups, you get revisions like ‘I don’t believe it’s possible’. It’s hard to argue with that.” …

The disagreement stems from the dawn of ancient-DNA research. In the 1980s, a young PhD student called Svante Pääbo worked behind his supervisor’s back at the University of Uppsala in Sweden to claim he had done what no one else had thought was possible: clone nuclear DNA from a 2,400-year-old Egyptian mummy². Soon researchers realized that they could use a new technique called polymerase chain reaction (PCR) to amplify tiny amounts of DNA from ancient samples. There was a burst of excitement as DNA was reported from a range of ancient sources, including insects preserved in amber and even an 80 million-year-old dinosaur³.

Then came the fall. It turned out that PCR, susceptible to contamination at the best of times, is particularly risky when working with tiny amounts of old, broken-up DNA. Just a trace of modern DNA — say from an archaeologist who had handled a sample — could scupper a result. The ‘dinosaur’ DNA belonged to a modern human, as did Pääbo’s pioneering clone. Once researchers began to adopt rigorous precautions⁴, including replicating results in independent labs, attempts to retrieve DNA from Egyptian mummies met with little success⁵.

That’s no surprise, say sceptics. DNA breaks up over time, at a rate that increases with temperature. After thousands of years in Egypt’s hot climate, they say, mummies are extremely unlikely to contain DNA fragments large enough to be amplified by PCR. “Preservation in most Egyptian mummies is clearly bad,” says Pääbo, now at the Max Planck Institute for Evolutionary Anthroplogy in Leipzig and a leader in the field. Ancient-DNA researcher Franco Rollo of the University of Camerino in Italy went so far as to test how long mummy DNA might survive. He checked a series of papyrus fragments of various ages, preserved in the similar conditions to the mummies. He estimated that DNA fragments large enough to be identified by PCR — around 90 base pairs long — would have vanished after only around 600 years⁶.

Yet all the while, rival researchers have published a steady stream of papers on DNA extracted from Egyptian mummies up to 5,000 years old. …
via Ancient DNA: Curse of the Pharaoh’s DNA : Nature News.

>How Bacteria Could Generate Radio waves

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Can bacteria generate radio waves?

On the face of it, this seems an unlikely proposition. Natural sources of radio waves include lightning, stars and pulsars while artificial sources include radar, mobile phones and computers. This is a diverse list. So it’s hard to see what these things might have in common with bacteria that could be responsible for making radio waves.

But today, Allan Widom at Northeastern University in Boston and a few pals, say they’ve worked out how it could be done.

They point out that many types of bacterial DNA take the form of circular loops. So they’ve modelled the behaviour of free electrons moving around such a small loop, pointing out that, as quantum objects, the electrons can take certain energy levels.

Widom and co calculate that the transition frequencies between these energy levels correspond to radio signals broadcast at 0.5, 1 and 1.5 kilohertz. And they point out that exactly this kind of signal has been measured in E Coli bacteria.

Let’s make one thing clear: this is a controversial area of science. The measurements of bacterial radio waves were published in 2009 by Luc Montagnier, who won the Nobel Prize for medicine in 2008 for the discovery of HIV. However, Montagnier is a controversial figure and it’s fair to say that his claims are not accepted by most mainstream biologists.

However, one of the criticisms of the work was that there is no known mechanism by which bacteria can generate radio waves. That criticism may now no longer hold.

That means Widom and co may be able to kickstart more work in this area. It is well known that bacterial and other types of cells use electromagnetic waves at higher frequencies to communicate as well as to send and store energy. If cells can also generate radio waves, there’s no reason to think they wouldn’t exploit this avenue too.

via How Bacteria Could Generate Radio waves – Technology Review.

>Bacteria Grow Under 400,000 Times Earth’s Gravity

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Proving that you don’t have to be big to be tough, some microbes can survive gravity more than 400,000 times that felt on Earth, a new study says.

Most humans, by contrast, can tolerate forces equal to about three to five times Earth’s surface gravity (g) before losing consciousness.

The extreme “hypergravity” of 400,000 g is usually found only in cosmic environments, such as on very massive stars or in the shock waves of supernovas, said study leader Shigeru Deguchi, a biologist at the Japan Agency for Marine-Earth Science and Technology.

Deguchi and his team were able to replicate hypergravity on Earth using a machine called an ultracentrifuge.

The scientists rapidly spun four species of bacteria—including the common human gut microbe Escherichia coli—to create increasingly intense gravity conditions.

The bacteria clumped together into pellets as the gravity increased, but their forced closeness didn’t seem to deter growth: All four species multiplied normally under thousands to tens of thousands of times Earth’s gravity.

Two of the species—E. coli and Paracoccus denitrificans, a common soil bacteria—grew under the strain of 403,627 g. …

via Bacteria Grow Under 400,000 Times Earth’s Gravity.

>Factory Uses Robots To Grow Human Skin

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Scientists at the Fraunhofer Institute for Interfacial Engineering and Biotechnology in Germany oversee a skin-making process controlled by robots. They currently produce 5,000 penny-sized disks of tissue every month, at around $72 per unit. It is hoped that in the future there will be many similar factories, mass-producing skin at a low cost for use in clinical testing and transplants in humans.

With robots and computers controlling the process, this maintains a sterile and climate-controlled environment for the skin to be developed, reducing the risk of contamination. Successfully engineered tissue for humans has been achieved but it is very costly and labor-intensive. Using robots as automated manufacturers would reduce both the cost and the manpower needed, enabling the efficient production of tissue, cartilage and even entire organs.

via Factory Uses Robots To Grow Human Skin – PSFK.

>Lemming hordes perish in Swedish roadside ‘massacre’

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Hordes of lemmings have been spotted leaving the safety of the mountains to make their way down to more inhabited areas, falling victim to traffic and being preyed upon by other animals.“I must have seen a thousand just since Saturday. They are absolutely everywhere. They are swimming about in the lake close to our house, they jump on the ice floes, and they scurry around the outside of our house,“ said holiday-maker Magnus Lundberg, to the local Östersundsposten (ÖP) daily.

Road users are reportedly struggling to avoid the advancing lemming hordes with many of the small furry animals ending up as road kill in what has been described as a real massacre on the roads.

However, Sweden’s pets and wild animals alike stand to gain as the lemming-strewn roads present a veritable feast for hungry predators.

Favourable weather has created the conditions for 2011 to become what Swedes call “a real lemming year”.

According to Birger Hörnfeldt, of the department of wildlife, fish and environmental studies at the Swedish University of Agricultural Sciences in Umeå, these traditionally occur every 3-4 years.

But the last three decades have seen such unfavourable weather that the number of lemmings had diminished considerably. …
Lemmings have traditionally been believed to undertake the occasional mass exodus, sometimes to meet their death by following each other off a cliff.

However, today this kind of migration behaviour is believed by experts to be a myth based on lies or at least highly exaggerated.

According to Bengt Landström of the mountain unit at the County Administrative Board in Norrbotten, this may well be a record year for lemmings, but he does not believe in a bona fide ‘lemming exodus’, where the lemmings blindly follow one another to their death.

“No, that kind of lemming migration is just a fairy tale, a tall story,“ he told local paper Piteå Tidningen.

Unfortunately, exodus or no exodus, the move from the mountaintops often means that the little rodents go to their death.

If they are not hit by cars wild or domestic animals are very keen to get their paws on them.

“Our dogs are eating the lemmings while we are out walking. It is not much we can do about it. The dogs just bite down on them, throw them up in the air and then swallow them almost whole. They probably devour between five and ten a day,” Magnus Lundberg told ÖP.  …

via Lemming hordes perish in Swedish roadside ‘massacre’ – The Local.

>The Brain’s Time Sense

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… “brain time,” as Eagleman calls it, is intrinsically subjective. “Try this exercise,” he suggests in a recent essay. “Put this book down and go look in a mirror. Now move your eyes back and forth, so that you’re looking at your left eye, then at your right eye, then at your left eye again. When your eyes shift from one position to the other, they take time to move and land on the other location. But here’s the kicker: you never see your eyes move.” There’s no evidence of any gaps in your perception—no darkened stretches like bits of blank film—yet much of what you see has been edited out. Your brain has taken a complicated scene of eyes darting back and forth and recut it as a simple one: your eyes stare straight ahead. Where did the missing moments go?

The question raises a fundamental issue of consciousness: how much of what we perceive exists outside of us and how much is a product of our minds? Time is a dimension like any other, fixed and defined down to its tiniest increments: millennia to microseconds, aeons to quartz oscillations. Yet the data rarely matches our reality. The rapid eye movements in the mirror, known as saccades, aren’t the only things that get edited out. The jittery camera shake of everyday vision is similarly smoothed over, and our memories are often radically revised. What else are we missing? When Eagleman was a boy, his favorite joke had a turtle walking into a sheriff’s office. “I’ve just been attacked by three snails!” he shouts. “Tell me what happened,” the sheriff replies. The turtle shakes his head: “I don’t know, it all happened so fast.”

A few years ago, Eagleman thought back on his fall from the roof and decided that it posed an interesting research question. Why does time slow down when we fear for our lives? Does the brain shift gears for a few suspended seconds and perceive the world at half speed, or is some other mechanism at work?

via David Eagleman and Mysteries of the Brain : The New Yorker.

>’Immortal’ Animals Reveal Anti-Aging Secrets

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… The animals that can possibly achieve immortality under ideal conditions, such as sea squirts, certain corals, Hydra, and Turritopsis nutricula (the immortal jellyfish), often activate telomerase. Helen Nilsson Sköld of the Department of Marine Ecology, University of Gothenburg, and colleague Matthias Obst are studying sea squirts and starfish to learn more about how these marine creatures seem to ward off aging.

Out of the animal immortality A-list, sea squirts and starfish have genes that most closely resemble those of humans.

“Animals that clone themselves, in which part of an individual’s body is passed on to the next generations, have particularly interesting conditions related to remaining in good health to persist,” Sköld was quoted as saying in the press release. “This makes it useful to study these animals in order to understand mechanisms of aging in humans.”

“My research has shown that sea squirts rejuvenate themselves by activating the enzyme telomerase, and in this way extending their chromosomes and protecting their DNA,” she added. “They also have a special ability to discard ‘junk’ from their cells. Older parts of the animal are quite simply broken down, and are then partially recycled when new and healthy parts grow out from the adult bodies.”

Starfish are also amazingly immune to problems that affect

the rest of us. If they lose a body part, for example, many species can simply grow another one. Reproduction involves tearing apart their bodies, somewhat akin to growing a new plant from a broken off piece of a “mother plant.”

Eternal life, from an evolutionary standpoint, however, has a big drawback. Due to asexual reproduction, the species as a whole retains very low genetic variation. This means they could be particularly vulnerable to climate change and not enjoy immortality after all.

Scientists are therefore rushing to study such species, which may hold the secrets of increasing our own longevity. …

via ‘Immortal’ Animals Reveal Anti-Aging Secrets : Discovery News.

>Switzerland: Smelly corpse flower draws thousands

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Thousands of people are flocking to the northern Swiss city of Basel to see a giant, stinky flower bloom for the first time.

The amorphophallus titanum – known as corpse flower because it exudes a smell of rotting flesh – is the first to blossom in Switzerland in 75 years.

The Basel Botanical Gardens expects the 6.6ft (2m) plant to attract 10,000 people whilst in bloom.

The bloom is set to wilt late Saturday or Sunday.

Worldwide, there have been only 134 recorded blooms from artificial cultivation, according to AP news agency.

The flower first began to poke out of the soil in March, and in the past few days it had been growing at about six centimetres a day, according to Swissinfo news website.

Its mother plant last bloomed in the Frankfurt Palm Garden in 1992.

Originally native to the tropical rainforests on the Indonesian island of Sumatra, the plant requires a humid climate to grow and rarely blossoms, even in the wild.

The flower’s smell, said to be a cross between burnt sugar and rotting flesh, is designed to attract insects for pollination.

via BBC News – Switzerland: Smelly corpse flower draws thousands.