Scientists turn living cell into laser

For the first time, scientists have created a laser using a living cell.

To make this biological marvel, the researchers used a single human kidney cell, a bit of jellyfish protein, a couple mirrors and blue light.

A typical laser has a “gain medium” — a material that amplifies light given off by another source — and an “optical cavity” — mirrors set up in a way that lines up the light waves.

When the outside source of light is trained on the gain medium its atoms become excited and release photons.

As the photons ricochet between the mirrors, passing through the gain medium over and over again, they stimulate other atoms to release more photons. While the photons would normally exit in random directions the way light comes out of a flashlight, the mirrors direct the wavelengths into one beam, forming a laser.

The experiment

In this case, the researchers made their gain medium out of the jellyfish protein — green fluorescent protein (GFP) — which is what makes jellyfish bioluminescent and is widely used in cell biology to label cells.

They then engineered human embryonic kidney cells to produce GFP, and placed one such cell between two mirrors. They trained an outside source of blue light on the cell, which then emitted a laser beam visible with the naked eye.

Quoting researcher Seok-Hyun Yun, an optical physicist at Harvard Medical School and Massachusetts General Hospital in Boston, this Nature News article reports,

The width of the laser beam is “tiny” and “fairly weak” in its brightness compared to traditional lasers … but “an order of magnitude” brighter than natural jellyfish fluorescence, with a “beautiful green” colour.

Surprisingly, the laser didn’t harm the cell in the process — quite a feat considering that even the earliest lasers could drill holes in razor blades.

The future of living lasers

A living laser could have numerous scientific applications, say Yun and co-author Malte Gather, who published their study in Nature Photonics.

Cell biologists could use living lasers to study the structure of cells. As seen in the photo, the cell produces light in an irregular pattern which scientists could study to determine the internal structure of the cell.

Living lasers could be useful in biotechnology and medicine, to create drugs that are activated by light or to treat disease by attacking cells deep within the body. But the main challenge to developing such internal applications is providing the initial outside source of light.

In a press release, Gather says,

“One of our long-term goals will be finding ways to bring optical communications and computing, currently done with inanimate electronic devices, into the realm of biotechnology. That could be particularly useful in projects requiring the interfacing of electronics with biological organisms. We also hope to be able to implant a structure equivalent to the mirrored chamber right into a cell, which would the next milestone in this research.”

Photo: Microscope image of a single-cell living laser in action. (Nature Photonics and Malte Gather, Wellman Center for Photomedicine, Mass. General Hospital.)

Personality Types - Longevity and the nature of the beast

A team led by Vincent Careau, a PhD student at University of Sherbrooke, gathered data on many aspects of dog biology published in disparate fields of study such as psychology, longevity, and veterinary research.

The information was well known in the respective research domains, yet they were never collated or put together. By doing so, the authors show that obedient breeds - on average - live longer than disobedient breeds. They also show that aggressive breeds have higher energy expenditure.

The late Don Thomas said, "It is hard to imagine how an aggressive personality could be adaptive if it lacked the energetic and metabolic machinery to back up the threats. Simply put, 100 pound weaklings don't kick sand in weight-lifters' faces and survive in nature."

This study contributes to the growing body of research revealing that personality is related to many crucial aspects of an animal's life - such as its energy needs, growth rate, age of first reproduction, and lifespan - and takes us a step closer to understanding the evolutionary causes and consequences of different personality types.

This study hints at the existence of underlying genetic linkages between personality, metabolism, and longevity -- meaning that selection for personality traits also invokes unintentional results on energetic and life history traits.

Link: http://www.journals.uchicago.edu

Gene therapy cures colour-blind monkeys - health - New Scientist

Gene therapy cures colour-blind monkeys - health - 16 September 2009 - New Scientist

Two colour-blind monkeys nicknamed Dalton and Sam have been "cured" through gene therapy.

The breakthrough could be a prelude to new gene treatments for human vision disorders that currently result in blindness. And because the treated monkeys were "middle aged", it challenges the assumption that gene therapies cannot work in adults because their brain connections are too set in their ways to change beneficially.

A human gene injected into the monkeys' eyes enabled them for the first time to produce Clong-wavelength opsin" the pigment sensitive to red and green light. "That gave them a retina like that of a normal person with full colour vision," says Jay Neitz at the University of Washington in Seattle.

The team used squirrel monkeys because the males are known to be colour-blind, whereas females have full colour vision. Males do have a full set of colour-sensing "cone" cells in their eyes, but they only make pigments for detecting blue and yellow light, making them blind to red and green.

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Artificial Intelligence and Genetic Engineering

An Robotic Invasion led by artificially intelligent machines. Consciousness in computer networks.

Hands across the AI Robotics Engineering Laboratory. Reach out to Intelligence in whatever form it may take!

Imagine a smartphone virus so smart that it can start mimicking you or worse, one that answers that pesky phonecall from your annoying friends. The one you always let go to voicemail and if you don't know who that annoying friend is, it's probably YOU!

You might think that such scenarios are laughably futuristic, but some of the world's leading artificial intelligence (AI) researchers are concerned enough about the potential impact of advances in AI that they have been discussing the risks over the past year. Now they have revealed their conclusions.

Until now, research in artificial intelligence has been mainly occupied by myriad basic challenges that have turned out to be very complex, such as teaching machines to distinguish between everyday objects. Human-level artificial intelligence or self-evolving machines were seen as long-term, abstract goals not yet ready for serious consideration.

Now, for the first time, a panel of 25 AI scientists, roboticists, and ethical and legal scholars has been convened to address these issues, under the auspices of the Association for the Advancement of Artificial Intelligence (AAAI) in Menlo Park, California. It looked at the feasibility and ramifications of seemingly far-fetched ideas, such as the possibility of the internet becoming self-aware.

The panel drew inspiration from the 1975 Asilomar Conference on Recombinant DNA in California, in which over 140 biologists, physicians, and lawyers considered the possibilities and dangers of the then emerging technology for creating DNA sequences that did not exist in nature.

Delegates at that conference foresaw that genetic engineering would become widespread, even though practical applications – such as growing genetically modified crops – had not yet been developed.

Genetic Disorders: Europe demands early testing of Children

CHILDREN should be tested for genetic disorders if their family history puts them at high risk, even if they don't show any symptoms, according to new Europe-wide guidelines.

Some European countries already have guidelines on testing children at risk of genetic disorders, but they disagree on when to carry out the tests. There is also the thorny issue of whether to test for disorders that can't be treated or prevented, says Pascal Borry of the Catholic University of Leuven (KUL) in Belgium, who helped write the new guidelines.

Now the European Society of Human Genetics is recommending immediate testing of children at increased risk of treatable conditions that appear in childhood, such as Duchenne muscular dystrophy and retinitis pigmentosa. Even if treatment is not an option, testing can be worthwhile as it may forewarn or reassure the family, but the child's interests must come first, says the society (European Journal of Genetics, DOI: 10.1038/ejhg.2009.26).

It also states that minors should be able to choose in the case of conditions that only occur later in life, such as inherited breast cancer, provided they understand the implications of the test. Such tests are particularly valuable if modifying lifestyle can lower the chance of getting the disease.