Virus may offer cancer insight
Updated 5:04 pm, Tuesday, December 18, 2012
Virus may offer cancer insight
UC Davis researchers believe they have discovered a new virus that may cause rare brain tumors in raccoons, and could help scientists better understand how viruses cause cancer in animals and humans.
The UC Davis team performed necropsies on 10 raccoons with brain tumors, which are very unusual in the animals. The team found a new virus in the tumors of all of the raccoons, nine of which lived in Marin County.
The new virus has since been named raccoon polyomavirus.
Viruses are known to cause several types of cancer in humans, including cervical cancer. Polyomaviruses, a type of small, DNA-based virus that can produce multiple tumors, can cause cancer in laboratory conditions, but it's unclear whether they cause cancer in natural environments in humans, because cancer takes so long to develop in people.
The raccoons, which have life spans of two or three years, may help scientists understand how polyomaviruses spread, how they may cause cancer and whether they can jump from species to species.
A paper on the new virus was published Dec. 12 in the journal Emerging Infectious Diseases.
Scientists focus on flawed protein
Two scientists at Gladstone Institutes in San Francisco are arguing that new emphasis needs to be placed on studying a misshaped protein that plays a major role in developing Alzheimer's disease - and could be the key to finally finding a way to treat it.
In a paper published this month in the journal Neuron, the scientists describe how the protein called apoE4 sets up a cascade of events that help lead to Alzheimer's. There are two other types of the apo protein - the others are called apoE2 and apoE3.
But apoE4 is the only one associated with Alzheimer's, and the scientists believe it has to do with an odd fold in the protein, which disrupts apoE4's ability to repair damaged neurons, as well as remove buildup of plaques in the brain.
Much of the research into treating Alzheimer's has focused on ways to remove the plaque buildup. But the Gladstone scientists believe that targeting the apoE4 protein, and finding a way to alter its shape so it's similar to the E2 and E3 proteins, may be more useful in treating the disease.
- Erin Allday
New finding about babies, faces
A new study from Stanford could explain why babies seem so enraptured by people's faces.
The study found that infants' visual systems are able to recognize faces at almost the same level as adults as early as four months old, well before they are able to decipher other images.
Researchers measured brain activity in adults and infants as they were shown various images, including faces and physical objects like phones or food. When shown faces, infants had similar brain activity responses as adults, although their responses were not as developed as those of adults.
But when shown everyday objects, infants used a different part of the brain that is associated with a more basic part of the visual system. That could explain why they do not process those objects as well as adults.
The study was published online this month in the Journal of Vision.
Possible way to measure suffering
Computer algorithms have the potential to offer clinicians some objective measure of their patients' pain, Stanford researchers are finding.
In a new study, the researchers performed MRIs on 47 people with lower back pain and 47 people without the pain and used a computer algorithm to read the scans. The algorithm predicted which person had back pain with 76 percent accuracy.
The study found that differences exist in the brains of people with and without lower back pain, which supports prior research that has shown the brains of people with chronic pain undergo changes.
Lower back pain may be associated with changes in the pain-processing parts of the brain, the study suggested.
Chronic lower back pain limits more Americans younger than 45 than any other condition. Overall, lower back pain affected 3.9 percent of Americans in 1992, but afflicted 10.2 percent in 2006.
The study was published online this week in Cerebral Cortex.
- Drew Joseph
Report sees rise in youth usage
Smokeless tobacco products have dramatically risen in popularity over the past decade in California, especially among youth, according to a report released last week by the state's Department of Public Health.
At the same time, overall sales of non-cigarette tobacco products rose to $210.9 million in 2011 from $77.1 million in 2001. Among high school students, the prevalence of such products rose to nearly 4 percent in 2010 from about 3 percent in 2004.
One especially popular smokeless-tobacco product is snus, which a user packs into his or her upper lip for a nicotine buzz. The number of places in California that sell snus significantly grew in three years, from less than 1 percent in 2008 to nearly 40 percent in 2011.
Public health officials said they were worried about these emerging trends. Still, fewer teens smoke in California than almost anywhere else in the country. Smoking rates among high school students dropped by more than one-third between 2000 and 2010.
- Stephanie M. Lee
Overuse by gynecologists found
A standard part of a gynecologic checkup is the pelvic exam. But that exam is frequently performed for medically unjustified reasons, according to a new UCSF study.
In a nationwide survey of 521 physicians specializing in obstetrics and/or gynecology, nearly all said they routinely conduct the exam in women who didn't have symptoms of gynecologic problems.
In addition, nearly half erroneously believe the pelvic exam is very important in screening for ovarian cancer. But long-standing medical guidelines discourage using the exam for this purpose.
And 87 percent said they'd perform the exam on healthy 18-year-olds, even though the American Congress of Obstetricians and Gynecologists recently recommended the exam not begin routinely until patients are 21.
So why do physicians do the exam anyway? Many said it's because patients have come to expect it. The UCSF team said their study, which appears online in the American Journal of Obstetrics and Gynecology, shows a need to educate doctors about the appropriateness of the exam.
- Stephanie M. Lee