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Meet the 2011 Nobel Laureates in Science

October 10, 2011 Leave a comment

Medicine

Bruce A. Beutler
Jules A. Hoffmann
Ralph M. Steinman

The Nobel Prize in Physiology or Medicine 2011 was divided, one half jointly to Bruce A. Beutler and Jules A. Hoffmann “for their discoveries concerning the activation of innate immunity” and the other half to Ralph M. Steinman “for his discovery of the dendritic cell and its role in adaptive immunity”.


Physics

Saul Perlmutter
Brian P Schmidt
Adam G Riess

The Nobel Prize in Physics 2011 was divided, one half awarded to Saul Perlmutter, the other half jointly to Brian P. Schmidt and Adam G. Riess “for the discovery of the accelerating expansion of the Universe through observations of distant supernovae”.


Chemistry

Dan Shechtman

The Nobel Prize in Chemistry 2011 was awarded to Dan Shechtman “for the discovery of quasicrystals”.

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New Machine Can Perform DNA Tests Within 3 Minutes

October 8, 2011 Leave a comment

“The Polymerase Chain Reaction, which amplifies specific DNA sequences out of mixtures (starting with as little as a single molecule), has revolutionized molecular biology, enabling DNA-based tests that once took months to be performed in an afternoon.

But even an afternoon is pretty slow for some purposes, such as diagnostic kits for infectious agents.

A team of impatient researchers at Lawrence Livermore National Lab has now managed to cut the time needed for a PCR reaction down from a few hours to less than three minutes.

PCR relies on a cyclical amplification process: high temperatures reset the DNA-copying reaction, lower ones let a new round of reactions start, and they proceed at an intermediate step.

The proteins that catalyze these reactions are actually very fast; the delay comes from the time neeed to shift the reactions between these temperatures.

Small machines called thermocyclers heat and chill metal blocks as quickly as they can, but it still takes minutes to get through a single cycle.

When a typical PCR reaction runs for 30 cycles, that can soak up a lot of time. This not only slows individual PCR reactions down, but also means that the thermocycler isn’t available for anyone else’s use.

The Livermore team tackled the heating and cooling very simply: their device has two reservoirs of water kept at the high and low temperatures needed during the cycle.

The water is pumped through a foamed copper block that contains the sample, enabling it to quickly equillibrate to the target temperature.

They also eliminated the time spent at the intermediate temperature, figuring the samples will pass through there long enough on their way between the two extremes.”

Brain Cells Injected into Pancreas May Cure Diabetes

October 7, 2011 1 comment

“Scientists in Japan have shown that implanting brain cells into a rat pancreas was a successful treatment for diabetes – rat diabetes.

In humans, the disease affects nearly 26 million people in the United States, 200 million worldwide. It costs us about $174 billion per year (that figure from 2007, it has likely increased), and in that same year it was the seventh leading cause of death. So if the the results could be repeated in humans, that would obviously be amazing.

In a press release, the scientists suggest that exactly that is their goal.

Tomoko Kuwabars and his colleagues at AIST Institute in Tsukuba, Japan, extracted neural stem cells from the hippocampus of rats, then injected them directly into the animals’ pancreases. The rats, which had been engineered to exhibit symptoms of diabetes, showed lower blood sugar levels (a good thing, since diabetes can dangerously increase blood sugar levels) after the brain cell injection. The scientists tested their theory that the neuronal cells were pumping out insulin by removing them, after which blood sugar levels went back up.”

Hiding From Magnets Behind a Cloak

September 24, 2011 Leave a comment

The magnetic cloak calls a truce on warring magnetic fields. On the left, the magnetic field of a lone cylinder-shaped magnet. In the middle, a second magnet, pointing the opposite way, disrupts its field. On the right, the second magnet's field is hidden in the cloak, which also allows the first magnet's field to extend as if the second weren't there at all. Credit: (illustration) J. Prat-Camps; A. Sanchez, C. Navau, D.-X. Chen/Autonomous U. of Barcelona

“The sneaky science of “cloaking” just keeps getting richer.

Physicists and engineers had already demonstrated rudimentary invisibility cloaks that can hide objects from light, sound, and water waves.

Now, they’ve devised an “antimagnet” cloak that can shield an object from a constant magnetic field without disturbing that field.

If realized, such a cloak could have medical applications, researchers say.

“This will take cloaking technology another step forward,” says John Pendry, a theorist at Imperial College London and co-inventor of the original cloaking idea, who was not involved in the present work.”

Driving Out Water to Find a Single Molecule

September 20, 2011 Leave a comment

“Imagine that you want to analyze someone’s blood for an incredibly rare molecule that is indicative of some disease. You get a few microliters of blood, and somewhere in that drop is the single molecule that you want to detect.

The chances of actually finding it are virtually nil, because single-molecule detection techniques generally rely on the molecule finding its way to some sensor surface or some other molecule that makes it even more visible…

What is required is some combination of techniques that retains single molecule sensitivity, but, at the same time, drives the molecule to the right place to be detected.

A very large group of Italian researchers have achieved just that by using a combination of hydrophobic surfaces and plasmonics to enhance the signal.”

Attack on a Single Cancer Cell Captured in 3D

September 15, 2011 Leave a comment

“That white blob on the left is one of the ninjas living inside your body, a Natural Killer blood cell. This photograph shows it attacking a cancerous cell (on the right) in unprecedented detail.

The image was captured in 3D by an Imperial College London research team lead by Professor Daniel Davis. They used a completely new technique developed with the help of physicists and the college’s Photonics Group: optical laser tweezers combined with a super-resolution microscope.

Before this technique, microscopes captured multiple bi-dimensional slices and scientists stacked them up to create a 3D image. The process was slow, limiting the speed of the action. Furthermore, the resulting detail and resolution was poor.”

Fluorescent Kitten May Help To Find AIDS Vaccine

September 12, 2011 Leave a comment

“This kitten may have the key to protect humans against HIV, the lentivirus that causes AIDS. He was genetically modified at the Mayo Clinic in Rochester, Minnesota. And yes, he glows in the dark.

His fluorescent fur and claws—which glow green in certain lighting—are not a side-effect of the gene that makes the cat resistant to the feline form of the HIV, known as the Feline Immunodeficiency Virus.

It’s caused by another gene that produces the Green Fluorescent Protein, which is naturally produced by the jellyfish Aequorea victoria.

The antiviral gene—which comes from a rhesus macaque—produces a less fun but much more useful protein, a restriction factor called TRIMCyp.

This protein can make T-cells—the blood cells that fight infections—resist viruses that cause AIDS in “a wide range of species”, according to Dr Laurence Tiley of the University of Cambridge.”