UPI NewsTrack Health and Science News

New algorithm charts fruit fly genetics

PITTSBURGH, June 29 (UPI) -- U.S. scientists say they've created a new algorithm that reveals how genetic networks in the fruit fly, Drosophila melanogaster, evolve.

Scientists have known the relationships between fruit fly genes change over time, but existing experimental approaches can't capture the details of those changes as they occur, the researchers said. The new algorithm, developed by Carnegie Mellon University scientists, incorporates machine learning techniques that enable researchers to figure out how the rewiring of the networks takes place as the insect develops.

"Many problems in biological, social and engineering systems require us to understand the interconnections between genes, people or other entities, but directly observing the evolution of these interconnections has often been impossible because of experimental or computational limitations," said Associate Professor Eric Xing. "Researchers typically could identify only a static 'average' network within each system over a period of time, but had no way to capture time-specific 'snapshots' of the actual rewiring network topology at consecutive clock-ticks within the period.

"Our new method exploits the information sharing between the evolving networks, and makes it possible to uncover interconnections that exist for a short moment in time," Xing said. "These findings help us to understand how these networks evolve over time, respond to stimuli and sometimes become dysfunctional."

The research that included Amr Ahmed appeared online in last week's early edition of the Proceedings of the National Academy of Sciences.

Gastrin's role in stomach cancer defined

NEW YORK, June 29 (UPI) -- U.S. scientists say they've determined both an overabundance and a lack of the hormone gastrin play key rolls in bacterial-induced stomach cancer.

More than 50 percent of the world's population is infected with Helicobacter pylori, which is strongly linked to the development of gastric ulcers and stomach cancer, researchers said.

Helicobacter infection results in increased expression of gastrin, a hormone that stimulates secretion of gastric acid, However, the role of gastrin in cancer development remains unclear, scientists said. High levels of gastrin lead to the development of stomach cancer, but an absence of gastrin has been shown to increase the numbers of tumors in the gastric antrum, the lower section of the stomach.

To reconcile that apparent disparity, a group led by Dr. Timothy Wang at the Columbia University Medical Center examined the contribution of Helicobacter infection to gastric cancer in animal models.

The researchers said they found Helicobacter infection in mice with high levels of gastrin resulted in cancer in the main body of the stomach, whereas infection in gastrin-deficient mice developed cancer in a different part of the stomach, the gastric antrum.

Gastrin, the scientists said, therefore, plays a key role in the development of Helicobacter-induced stomach cancer, but may have distinct effects on carcinogenesis in different parts of the stomach.

The research is reported in the July issue of The American Journal of Pathology.

NASA plans electronic von Braun collection

WASHINGTON, June 29 (UPI) -- The U.S. space agency says it's seeking ideas about how to analyze and catalog an electronic, searchable Wernher von Braun database.

NASA is soliciting comment from the public, academia and industry on how to create the database on the eve of the 40th anniversary of the historic first moon landing in 1969.

Von Braun was the first director of NASA's Marshall Space Flight Center in Huntsville, Ala., and a key figure in the development of the Saturn V rocket and NASA's Apollo program.

"NASA has a full collection of "Weekly Notes" von Braun wrote during the 1960s and 1970s," the space agency said. "These notes were used to track programmatic and institutional issues at Marshall, and are considered by many historians to be a valuable source of data."

Space agency officials say they are looking for concepts that will provide an innovative resource for agency engineers and scientists, as well as researchers in academia and industry.

More information and the request for information is available at http://www.nasa.gov/directorates/somd/home/von_Braun_RFI.html.

Ebola infection blocked in cell experiment

GALVESTON, Texas, June 29 (UPI) -- University of Texas scientists say they have blocked Ebola infections in cell culture experiments, an achievement that may lead to a therapy for the disease.

The researchers at the university's Medical Branch said they discovered two biochemical pathways the Ebola virus relies on to infect cells. Using substances that block the activation of those pathways, the scientists prevented Ebola infection in the cell cultures.

Associate Professor Robert Davey, lead author of the study, said the team used new computational and analytical techniques to focus more on the host cell than the virus.

"The premise for this work is that the virus is essentially nothing without a cell," said Davey. "It needs to rely on many cell proteins and factors for it to replicate. The idea is that if we can suppress the expression of those cell proteins for just a short time, we can then stop the disease in its tracks."

The study is detailed in the journal Drug Discovery Research.