a chemical that could allow people with degenerative blindness to see again.

WASHINGTON: In a major advance in the field of vision restoration, scientists claimed to have discovered a chemical that could allow people with degenerative blindness to see again.

A team of University of California in collaboration with researchers at the University of Munich and University of Washington are working on an improved compound that temporarily restores some vision to blind mice. The compound called 'AAQ' is less invasive than implanting light-sensitive electronic chips in the eye.

The approach could eventually help those with retinitis pigmentosa, a genetic disease that is the most common inherited form of blindness, as well as age-related macular degeneration, the most common cause of acquired blindness in the developed world. In both diseases, the light sensitive cells in the retina, the rods and cones, die, leaving the eye without functional photoreceptors.

The chemical AAQ acts by making the remaining, normally "blind" cells in the retina sensitive to light, said lead researcher Richard Kramer, UC Berkeley professor of molecular and cell biology.

AAQ is a photoswitch that binds to protein ion channels on the surface of retinal cells.

When switched on by light, AAQ alters the flow of ions through the channels and activates these neurons in the same way rods and cones are activated by light.

"This is similar to the way local anesthetics work: they embed themselves in ion channels and stick around for a long time, so that you stay numb for a long time," Kramer said. "Our molecule is different in that it's light sensitive , so you can turn it on and off and turn on or off neural activity," said Kramer.

Because the chemical eventually wears off, it may offer a safer alternative to other experimental approaches for restoring sight, such as gene or stem cell therapies, which permanently change the retina . "This is a major advance in the field of vision restoration ," said co-author Russell Van Gelder, from the University of Washington. PTI

Now, a cancer drug to flush out dormant HIV

WASHINGTON: A drug used to treat certain types of cancer is able to dislodge hidden virus in patients receiving treatment for HIV, researchers have claimed.

University of North Carolina at Chapel Hill in a study found the existence of persistent reservoirs of dormant HIV in the immune system that are not attacked by anti-AIDS drugs, believed to be a major reason why infection re-emerges once patients stop taking their medication. The disruption of these reservoirs is critical to finding a cure for AIDS.

Researchers at UNC, working in collaboration with scientists from the Harvard School of Public Health, National Cancer Institute and the University of California undertook a series of experiments designed to evaluate the potential of the drug vorinostat . Vorinosta is a deacetylase inhibitor that is used to treat some types of lymphoma, to activate and disrupt the dormant virus.

Laboratory experiments measuring active HIV levels in CD4+T cells, which are specialized white blood cells that the virus uses to replicate, showed that vorinostat unmasked the hidden virus in these cells. Subsequently, vorinostat was administered to eight HIV-infected men who were medically stable on antiretroviral therapy and the levels of active HIV virus were measured and compared to the levels prior to administration.

Scientists discover solar system, parallels our own

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2 hours ago  •  Sid Perkins - The Washington Post

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Scientists have discovered a distant solar system very much like our own, in which the orbits of all known planets lie in nearly the same plane and are aligned with the star's rotation.
In recent years, astronomers have discovered a flurry of solar systems filled with exotic planets such as massive "hot Jupiters" that orbit close to their parent star, and rocky "super Earths" between one and 10 times the size of our planet. Some of these exoplanet systems have been discovered through wobbles of the star due to gravitational interactions with the orbiting planets; others betrayed their presence when planets regularly passed in front of, or transited, their parent star, temporarily blocking some of the light streaming toward telescopes here.
Earlier this year, using data gathered by NASA's Kepler spacecraft (which is designed to monitor thousands of stars for hints of transiting planets), scientists discovered three planets circling a star dubbed Kepler-30, which is about the size and mass of our sun. One planet, with a diameter about four times that of Earth, orbits the star every 29 days; the other two, each with a diameter at least 10 times that of Earth, orbit the star every 60 days and 143 days, respectively. Further analysis revealed a huge, dark starspot on Kepler-30, similar to the sunspots that blemish the face of our sun.
By tracking the spot, researchers determined that the star rotates once every 16 days or so. That's about half the time our sun needs to rotate, which suggests that Kepler-30 is a relatively young, very active star --and that, in turn, helps explain why its starspot is so large and so persistent, says team leader Roberto Sanchis-Ojeda, an astrophysicist at the Massachusetts Institute of Technology in Cambridge.
Now, detailed analyses of the variations in light reaching Kepler's sensors over a 30-month period reveal that the three known planets not only pass in front of the star as seen from Earth, but they repeatedly pass in front of the dark spot on Kepler-30's surface. This reveals critical information about the distant solar system, Sanchis-Ojeda and his colleagues suggest: The planets' orbits are aligned within a few degrees of one another, and the planes of those orbits are closely aligned with the rotational plane of the parent star, a remarkable parallel to our solar system, the team reports Wednesday in Nature.
"For the first time, we can probe a system of planets that looks like our own," says Sanchis-Ojeda.
Although the Kepler-30 system isn't the only one known to have planets orbiting in closely aligned planes, it is the first for which scientists have also determined the plane in which the parent star rotates.
"There are relatively few solar systems like ours," says Drake Deming, an astronomer at the University of Maryland, College Park. "Every time we find one more, that's a big increase."
The team's analytical technique could be used to find more solar systems like ours, Deming says. Many of the stars in Earth's neighborhood are small stars called red dwarfs. Standard planet-detection methods don't work well with red dwarfs because they're cool and emit relatively little light, mostly in red and infrared wavelengths at which Kepler and other planet-observing sensors now in use aren't efficient.
But these stars are also very active and often have large starspots, so if spaceborne instruments specifically designed to scan for transiting planets around such stars were launched, the results could shed new light on how common planetary systems similar to our own might be. "We don't really understand how such systems form around cool stars," Deming notes.