A report of an individual infected with a second strain of HIV despite effective drug treatment following the first infection has researchers concerned. “For the first time, we’ve shown it is possible for an individual to become infected with two closely related strains of HIV,” says Bruce D. Walker, M.D., a researcher at Massachusetts General Hospital and Harvard Medical School. The findings underscore the challenges vaccine developers face in creating a broadly effective vaccine against HIV. The first HIV vaccines may not prevent infection altogether, but rather may prevent HIV from causing disease by limiting the virus’ ability to reproduce, explains Dr. Walker. This case shows that a hypothetical vaccine against one strain of HIV may not necessarily protect the vaccinee against other, closely related strains.
Many neurological diseases occur when specific groups of neurons die because of nerve damage, toxins, inflammation, or other factors. A new study suggests that activity of a single gene can stop neurons from dying regardless of what triggers this process. The findings could lead to new ways of treating neurodegenerative diseases.
This weekend I sank my teeth into some delicious beef ribs. But researchers at the Forsyth Institute say they’ve done one better ? they’ve sunk pork teeth into rat guts. The experiment involved taking seeded cells from immature teeth of six-month-old pigs and placing them in the intestines of rats (who no doubt were thrilled at the addition). Within 30 weeks, small tooth crowns made of enamel and dentin had formed. Within five years, the Forsythe team says, they hope to be able to harvest teeth of specific size and shape, and five years after that to regrow human teeth.