Scientist think they've found HIV weakness
HOUSTON, July 16 (UPI) -- HIV researchers at the University of Texas Medical School in Houston said they think they've found the chink in armor of the virus linked to AIDS.
The vulnerable spot is hidden in a protein essential for the Human Immunodeficiency Virus, the virus that causes Acquired Immune Deficiency Syndrome, to attach to host cells, the university said in a release.
An HIV vaccine doesn't exist because HIV is a mutating virus.
The scientists said they are focusing on a stretch of amino acids on HIV's envelope protein gp120.
"Unlike the changeable regions of its envelope, HIV needs at least one region that must remain constant to attach to cells. If this region changes, HIV cannot infect cells," said Sudhir Paul, a pathology professor at the UT Medical School.
Paul's group engineered antibodies with enzymatic activity, called abzymes, that can attack the virus's weakness.
"The abzymes recognize essentially all of the diverse HIV forms found across the world. This solves the problem of HIV changeability," Paul said. "The next step is to confirm our theory in human clinical trials."
The theory was in a recent issue of Autoimmunity Reviews and will be presented during the International AIDS Conference Aug. 3-8 in Mexico City.
Unmanned flights give peek at melting ice
WASHINGTON, July 16 (UPI) -- Aircraft flying over Greenland will offer a view of the melting Greenland Ice Sheet and its potential for raising the global sea level, U.S. scientists said.
The two unmanned Manta planes will help scientists determine whether the ice sheet's melt rate will accelerate, Betsy Weatherhead of National Oceanic and Atmospheric Administration's Earth System Research Laboratory said in a news release.
A view of the region from 500-1,000 feet above the ice can provide fine-scale measurements of the water and surface of the glaciers, said Weatherhead, a scientist for the Arctic test bed of NOAA's Unmanned Aircraft Systems program. The Mantas can provide that view, cruising at low altitudes over little-known terrain without endangering humans.
The Greenland Ice Sheet is shrinking at a rate of 40-50 cubic miles annually, a pace that's accelerating, NOAA said. Better observations could help explain the role of short-lived surface lakes and why the edges of the ice sheet are melting so fast.
"We're concerned that as temperatures rise, more heat will cause more melting, more melting will create bigger lakes, and the rate of ice loss will accelerate," said NOAA's John Adler, the project manager.
The unmanned flights will last three weeks.
Eggs of water-bound fleas get around
LEUVEN , Belgium, July 16 (UPI) -- Scientists in Belgium say they've figured out how water fleas, unable to survive outside water, disperse eggs among ponds -- they hitchhike.
Frank Van de Meutter and colleagues of the Catholic University of Leuven in Belgium said pond-dwelling insects call backswimmers provide the Daphnia water fleas' eggs with a ride as they flit among ponds, New Scientist reported Wednesday.
Researchers put backswimmers in a bucket of water with 1,000 eggs then allowed them to take flight, caught them and examined them for the presence of eggs.
Of 45 backswimmers caught, researchers found 30 had eggs attached. Researchers found the insects' hairy abdomens allowed eggs to attach, explaining how the Daphnia catch a ride from pond to pond.
"Even after the backswimmers were rather roughly caught with a bucket, Daphnia eggs remained attached to the body, especially on the hairy keel at the underside of the abdomen and on the haired parts of the legs," says Van de Meutter.
Scientist study genetic variants and HIV
SAN ANTONIO, July 16 (UPI) -- A genetic variation that once may have protected people of African descent from HIV now may increase their susceptibility to the virus, U.S. scientists said.
The variation is one of the first genetic risk factors for HIV identified only in people of African descent, spotlighting how genetics play a role in susceptibility to Human Immunodeficiency Virus, the virus that causes AIDS, the University of Texas Health Science Center at San Antonio said Wednesday in a news release.
In a population of 1,266 HIV-positive U.S. military personnel and 2,000 non-infected healthy personnel, researchers studied the gene that expresses Duffy antigen receptor, a molecule on the surface of red blood cells where the malaria species Plasmodium vivax attaches.
"Duffy antigen influences levels of inflammatory and anti-HIV blood factors called chemokines," said Dr. Weijing He, first author of the paper published in Cell Host & Microbe. "Other as-yet undefined host factors likely exert population-specific effects on HIV-AIDS, such that individuals of European or African descent are likely to have distinct host factors that affect their respective susceptibilities to HIV and AIDS."
The majority of people in sub-Sahara Africa don't express Duffy on their red blood cells, said senior lead author Robin Weiss of University College London.
"This is one of the first genetic factors particularly common in Africans that has been shown to confer more susceptibility to HIV," Weiss said.
