UPI NewsTrack Health and Science News

MicroRNAs regulate cancer stem cells

BOSTON, Dec. 13 (UPI) -- U.S. and Chinese researchers say they've discovered a key molecular switch belonging to a class of molecules called microRNAs that regulate cancer stem cells.

A report, published in the journal Cell, said the microRNAs push the stem cells to become more differentiated and less tumorigenic through their ability to switch off particular genes.

"People know that microRNAs are important regulators of cell differentiation, but nobody has shown that they regulate the critical properties of cancer stem cells, or any kind of stem cells," Judy Lieberman -- an investigator at the Immune Disease Institute and Harvard Medical School professor of pediatrics at Children's Hospital Boston -- said Thursday in a release.

The report said the findings suggest a novel way to target these cells to treat cancer with therapeutic RNAs, which are a new class of medicine under development for many diseases.

Scientists laud fuel economy bill

WASHINGTON, Dec. 13 (UPI) -- The U.S. Senate's passage of stricter vehicle fuel economy standards for the first time in three decades Thursday drew praise from a scientists' group.

The measure, passed on an 86-8 vote, also would require a significant increase in biofuel production, though the Senate couldn't come to terms on renewable energy standards and tax incentives. Still, the measure is expected to pass the House next week and be sent to President George W. Bush.

"We've turned a corner. Congress has finally taken action to cut America's oil dependence by giving the country more fuel efficient cars and trucks," said Michelle Robinson, director of Union of Concerned Scientists' Clean Vehicles Program. "Now the only thing standing between Americans and relief at the pump is the president's signature."

The legislation would require automakers to achieve a fleetwide average of at least 35 miles per gallon by 2020, up more than 10 mpg from the current level. The bill also would require the production of up to 36 billion gallons of renewable fuels by 2022, with 21 billion gallons coming from fuels releasing at least 50 percent less global warming pollution than gasoline. In addition,16 billion gallons of biofuels would have to come from cellulosic biofuels.

FDA panel moves Adiana permit forward

BEDFORD, Mass., Dec. 13 (UPI) -- A U.S. Food and Drug Advisory Panel has given pre-market approval to a female sterilization system that would provide permanent non-surgical birth control.

Hologic Inc. said the Adiana Transcervical Sterilization System provides women with a safe and effective permanent transcervical alternative to tubal ligation.

The FDA Obstetrics and Gynecology Devices Advisory Panel recommended approval of the device contingent upon several conditions, including long-term follow-up of current pivotal trial patients, a post-approval study of new patients and physicians, and more specific labeling recommendations, Hologic said Thursday in a release.

The FDA is not required to accept, but traditionally follows the recommendations of, its advisory panels.

The device -- which was tested on 645 women in the United States, Australia and Mexico -- was 98.9 percent effective at preventing pregnancy during the 12 month testing period, the company said.

Dust from China routinely appears in U.S.

SAN FRANCISCO, Dec. 13 (UPI) -- A U.S. researcher says dust from deserts in China and Mongolia is adding to the mix of air pollution in the United States.

Emily Fischer, a University of Washington doctoral student in atmospheric sciences, said dust from the Gobi and Taklimakan deserts is routinely present in the air over the western United States during spring months.

"We are interested in Asian dust that comes across the Pacific because particles can have an impact on health, as well as on visibility," Fischer said Thursday in a news release.

Fischer found that in years with large Asian dust storms there was an increase in particles of 2.5 microns or less in the air over the western United States. Particles that small can be inhaled more deeply into the lungs and so are a greater health concern.

The research is being presented this week at the annual meeting of the American Geophysical Union in San Francisco.

"The transport of dust across the Pacific is not a new phenomenon," Fischer said. "But we are just beginning to understand it and quantify it on a year-to-year basis instead of on a case-by-case basis.