17 January 2007
Dust around nearby star resembles a skier's dream
Berkeley astronomers have found that the dust grains surrounding a nearby red dwarf star have a fluffiness comparable to that of powder snow.
This is the first definitive measurement of the porosity of dust outside our solar system, say the researchers. It advances our understanding of the era after the formation of planets, but before the remaining snowball-size rubble was ground into dust by collisions and blown out of the inner solar system.
"We believe that this porosity is primordial, and reflects the agglomeration process whereby interstellar grains first assembled to form macroscopic objects," says astronomy professor James Graham. He and Paul Kalas, an assistant adjunct professor of astronomy, discussed their findings on Jan. 7 at a meeting of the American Astronomical Society.
Peptide targets latent papilloma virus infections
While a newly marketed vaccine promises to reduce drastically human papilloma virus (HPV) infections, the major cause of cervical cancer, a new discovery by Berkeley researchers could someday help the millions of people already infected and at constant risk of genital warts and cancer.
One study found that 75 percent of sexually active men and women under 50 have, or have had, an HPV infection, while 10,000 women annually develop cervical cancer, more than 90 percent of which is caused by HPV. Four thousand women die of cervical cancer each year.
Once infected, it's difficult to rid oneself of the virus, which hides as latent DNA in cells of epithelial tissue, spreading as these cells divide.
The Berkeley team created a protein fragment, or peptide, that prevents the virus from hitching a ride on a cell's chromosomes as the cell divides. If such a peptide - or a drug that mimics its actions - works in the body, it would stop the virus from spreading or generating warts, which can progress to cancer.
"We're optimistic that this will work generally for many different genetic variants of human papilloma virus, though it's too early to say how many of the genotypes of this virus will respond," says Michael Botchan, professor of molecular and cell biology and a faculty affiliate of the Berkeley branch of the California Institute for Quantitative Biology. "The hope is to have one drug that works for all different human virus types."