Clue against Flu
A goal in fighting influenza is a universal vaccine, one that works on many strains of the pathogen [see “Beating the Flu in a Single Shot”; Scientific American, June 2008]. But the virus’s outer coat, consisting mainly of proteins called hemagglutinin and neuraminidase, frequently mutate, forcing the reformulation of vaccines every season. Two studies report the discovery of human antibodies that target an area on hemagglutinin that does not change much. (In contrast, current drugs, such as Tamiflu, aim for neuraminidase.) In tests, one of the antibodies protected mice from lethal doses of avian flu (H5N1) and other strains. Large amounts were needed, however, so any human treatment could be expensive. The papers were published in the March Nature Structural and Molecular Biology and online February 26 by Science Express.
The mass extinction at the end of the Permian period 250 million years ago wiped out at least 90 percent of all ocean species and 70 percent of land vertebrates [see “The Mother of Mass Extinctions”; Scientific American, July 1996]. New findings suggest the deadly event on land might have occurred separately from the one in the oceans.
Paleontologist Robert Gastaldo of Colby College and his colleagues investigated ancient sedimentary rock at South Africa’s Karoo Basin. Previous expeditions there had identified a distinct boundary between the Permian and the Triassic, which came right after. Dubbed the “lifeless zone,” this sediment lies over fossils of extinct reptiles and has been the primary evidence of the end-Permian extinction’s rapid effects on land.
But now Gastaldo’s team has discovered that some of the sediment lies roughly eight meters below the Permian-Triassic boundary—and at some places it lies below those fossils, meaning it was deposited well before the catastrophe was thought to have happened on land. The change in timing suggests that the land and marine extinctions could have had different triggers. Culprits that could have altered the climate and oceans in a deadly way include sustained volcanism and continental drift. Dig into the March Geology for more.
—Charles Q. Choi
Legal Side Effects
Drug companies have been left wide open for lawsuits by a March 4 U.S. Supreme Court decision allowing juries to award damages for harmful side effects, even if the drug had proper, FDA-approved warning labels. This ruling, against Wyeth Pharmaceuticals, may encourage more settlements, such as those for Merck’s painkiller Vioxx, which triggered heart attacks in some patients [see “Doubt Is Their Product”; Scientific American, June 2005]. It could also provide impetus for new legislation to permit lawsuits against medical device makers, which the court shielded from suits last year.
As expected, President Barack Obama signed an executive order on March 9 lifting a ban on stem cell research imposed by the Bush administration in 2001. That restriction had limited scientists who received federal funding to 21 lines of embryonic stem cells, possibly hampering efforts to transform the cells into therapies [see “The Future of Stem Cells”; Scientific American, July 2005]. Now investigators can use hundreds of new lines, and some of the $10 billion in the economic stimulus package for health care research will likely flow into embryonic stem cell work. The Department of Health and Human Services will issue ethical and reporting guidelines this summer.