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Health&Science M ONDAY, SE P T E M BE R 11, 20 0 6 Moral opinion at odds with science Foes of premarital sex redirect focus from HIV. L ately, opponents of premarital sex have shifted focus from the threat of HIV to the sheer number of sexually transmitted infections and the way some of these come in many different strains. Take this passage from a letter recently printed in The Inquirer opposing the use of a vaccine to protect against two cancer-linked human papillomaviruses: “ … Yes, our daughters may reduce their rates of cervical cancer caused by just two of the more than 100 strains of HPV but they could contract some other sexually transmitted disease that will eventually kill them.” To some people, the fact there are 100 strains of HPV speaks to the danger of sex. To scientists, it suggests nothing of the sort, since most strains aren’t sexually transmitted. For them, the issue poses a scientific puzzle about the coevolution of humanity and our viruses. What we do know is that two strains of HPV cause 80 percent of cervical cancer cases. Because the vaccine protects against these, it’s expected to save lives. About 13 other strains can more rarely lead to the disease. So while it’s true the vaccine won’t offer perfect protection, it’s also the case that if you’re worried about all 100 HPV strains, even lifelong abstinence won’t shield you. You can be the most unsullied of virgins and still get an HPV from shaking hands with someone or walking barefoot. Some will cause ugly warts to form on various parts of your virginal body. Why do diseases divide up into different strains in the first place? One researcher who’s shed some light on this is matheSee HPV on C2 SECTION C The Philadelphia Inquirer B Harvesting Neurons From the Nose WWW.PHILLY.CO M Olfactory neurons are Unlike sensory cells elsewhere in the body, the cells in the nose are both easily removable and very similar to brain cells. Researchers are studying them for clues into mental illness. removed through the nostril. These cells are then dosed with various odors and drugs to see how they react. To date, scientists have found differences in cells of people with bipolar disorder and are studying other mental illnesses. Brain Neurons Olfactory bulb SOURCE: Monell Chemical Senses Center; University of Pennsylvania Olfactory neurons Olfactory epithelium ROBERT WEST / Inquirer Staff Artist Olfactory membrane Cilia The nose knows Olfactory neurons, local scientists have found, can reveal a lot about live brain cells and mental illness. And they’re easy to study. Inside HEALTH & SCIENCE Faces saved: Portraits of people whose lives have been improved by facial surgery. C2. Personal Health: F By Tom Avril INQUIRER STAFF WRITER or the millions of Americans who take drugs to treat mental illness, about the only way psychiatrists can tell whether the medications are working is through observation and asking patients how they feel. And even when doctors do find the right drugs, they can’t explain exactly why the meds are effective. It’s the glaring void at the heart of mental health treatment. No one, from the scientists developing drugs to those who prescribe them, is able to examine the diseased tissue: the cells of the human brain. Enter Nancy Rawson, a cell biologist at Monell Chemical Senses Cen- ter in Philadelphia. She does it through the nose. Working with colleagues at the University of Pennsylvania and Thomas Jefferson University, Rawson takes advantage of a scientific curiosity: The sensory cells in the nose, unlike those elsewhere in the body, are very similar to neurons in the brain, Rawson says. And they can be easily plucked out for study, a few hundred at a time, because they grow back. In recent years, researchers have developed several methods to probe the mind, from analysis of spinal fluid to imaging methods such as MRIs and PET scans. But looking at olfactory neurons — located high in the nose, directly connected to the See NOSE on C3 TOM GRALISH / Inquirer Staff Photographer Dr. Edmund Pribitkin harvests neurons from the upper nose of healthy volunteer Jerome Lennon at Thomas Jefferson University. All-terrain vehicles unhealthy for kids. C2. Earth once may have spun in more than one direction: Magnetic evidence points to the center of mass changing. ARTS & ENTERTAINMENT Live Arts/Philly Fringe: You’re invited to Lee Ann Etzold’s bizarre and funny dinner party, “P’s & Q’s.” C8. W hile studying pieces of 800 million-year-old limestone from Norway, scientists found the Earth may once have been seriously out of balance, they reported last month in the Geological Society of America Bulletin. Like little compasses frozen in time, magnetic grains embedded in successive layers of rock showed an apparent large movement of the North Pole over several million years. Philadelphia Museum of Art PUBLIC PROGRAMS But the scientists say it doesn’t seem that the pole and the Earth’s axis of rotation actually “moved.” The samples suggest that while continuing its regular daily rotation about the polar axis, the Earth may also have slowly spun a sixth of a turn in another direction at the same time. The big move could have been due to some sort of subsurface imbalance — an upwelling or downwelling in the Earth’s mantle that shifted the planet’s center of mass. If true, it is the most dramatic example yet of a phenomenon known as true polar wander, which has occurred to a much lesser degree at other periods in history. The spin shifted the continents to unfamiliar places. Australia was up above the equator, said Princeton University geologist Adam Maloof, who helped gather the rocks. Magnetic grains in rocks from a few million years later suggest that the imbalance subsided and the Earth returned to its original orientation. The Norwegian rocks were not consistent with other explanations for the alignment of the magnetic grains, such as continental drift, Maloof said. But their hypothesis will be tough to prove, since few rocks remain from back then. One of the few places with rocks from the correct period is Australia. So Maloof and company are going Down Under this summer. — Tom Avril Get Smart! ADVERTISEMENT For more information, visit philamuseum.org or call (215) 684-7580 BETO ALVAREZ / Inquirer Staff Artist Rocks suggest unbalanced past