UPI NewsTrack Health and Science News

NASA to inspect Haitian quake fault lines

PASADENA, Calif., Jan. 27 (UPI) -- NASA says it has added several science overflights of earthquake faults in Haiti and the Dominican Republic to a previously scheduled airborne radar project.

The space agency's Uninhabited Aerial Vehicle Synthetic Aperture Radar, or UAVSAR, left NASA's Dryden Flight Research Center in California Monday aboard a modified NASA Gulfstream III aircraft.

The three-week overflight of the island of Hispaniola will involve the use of the L-band wavelength radar developed by NASA's Jet Propulsion Laboratory to study the structure of tropical forests, monitor volcanic deformation and examine Mayan archaeological sites.

After the Jan. 12 Haitian earthquake, NASA managers said they added science objectives that will allow UAVSAR's observational capabilities to study geologic processes.

"UAVSAR will allow us to image deformations of Earth's surface and other changes associated with post-Haiti earthquake geologic processes such as aftershocks … and the potential for landslides," said the laboratory's Paul Lundgren, the principal investigator for the Hispaniola overflights.

NASA said flight plans call for multiple observations through early to mid-February.

HIV infection or medications age brain

ST. LOUIS, Jan. 27 (UPI) -- Human immunodeficiency virus infection or its treatments age the brain prematurely, U.S. researchers found.

Dr. Beau Ances of Washington University School of Medicine in St. Louis and colleagues at the University of California-San Diego reported brain blood flow of patients infected with HIV resembled the brains of uninfected people 15-20 years older.

"Brain blood flow levels decline naturally as we age, but HIV, the medications we use to control it or some combination of the two appear to be accelerating this process independent of aging," Ances said in a statement.

Ances and colleagues used magnetic resonance imaging scanners and a technique known as arterial spin labeling to examine a group of 26 patients with HIV and a group of 25 uninfected controls comparable in mean age range and education.

In addition to finding the brain blood flow values significantly reduced in subjects with HIV versus the uninfected controls, the researchers determined the brains of those in the HIV infected group needed to work harder to get an assigned task done. The researchers also reported reduced brain blood flow even among young, recently infected patients with HIV.

The findings are published in the Journal of Infectious Diseases.

Study: X-rays can form crystals

EVANSTON, Ill., Jan. 27 (UPI) -- U.S. scientists say they've discovered X-rays can trigger the formation of a new type of crystal -- charged cylindrical filaments.

The Northwestern University researchers said the filaments are ordered like a bundle of pencils experiencing a repulsive force, which is unknown to occur in crystals.

The findings, said the scientists, expand scientific knowledge of crystals and might lead to the use of X-rays to control the structure of materials or to develop novel biomedical therapies.

"This is a very intriguing and astonishing result," Professor Samuel Stupp, the paper's senior author, said. "The filaments are charged so one would expect them to repel each other, not to organize into a crystal. Even though they are repelling each other, we believe the hundreds of thousands of filaments in the bundles are trapped within a network and form a crystal to become more stable."

The research is reported in the journal Science.

Atrial fibrillation outcomes studied

MAYWOOD, Ill., Jan. 27 (UPI) -- A U.S. study suggests catheter ablation, in which energy is emitted from a catheter to eliminate the source of an irregular heartbeat, is a preferred therapy.

The scientists involved in the multi-center randomized study led by Dr. David Wilber of Loyola University Medical Center said there were significantly better outcomes in catheter ablation patients with paroxysmal atrial fibrillation -- intermittent cardiac rhythm disturbance -- who had not responded previously to anti-arrhythmic drug therapy.

Atrial fibrillation patients have an increased long-term risk of stroke and heart failure, the scientists said.

Wilber and his colleagues conducted a study to compare catheter ablation with anti-arrhythmic drug therapy. The study was conducted at 19 hospitals and included 167 patients.

The researchers found that at the end of the 9-month evaluation, 66 percent of patients in the catheter ablation group remained free from protocol-defined treatment failure compared to 16 percent of patients treated with anti-arrhythmic drug therapy.

"Similarly, 70 percent of patients treated by catheter ablation remained free of symptomatic recurrent atrial arrhythmia versus 19 percent of patients treated with (drug therapy)," Wilber said. "In addition, 63 percent of patients treated by catheter ablation were free of any recurrent atrial arrhythmia versus 17 percent of patients treated with ADT,"

The study appears in the Journal of the American Medical Association.