By Barbara Hale
Public Information
College age men who said they weren't inclined to eat low-fat foods were more easily influenced by false content labels than fat-and calorie-conscious women in a recent study.
Fed a low-fat, low-calorie lunch that was falsely labeled "High Fat/High Calorie," the men reported less hunger and ate significantly fewer snacks later on than when they were fed the very same lunch correctly labeled "Low Fat/Low Calorie." The women, on the other hand, ate the same amount of snacks regardless of the labeling or actual fat and calorie content of their lunch.
Women rated the lunches labeled "Low Fat/Low Calorie" significantly higher in "liking" and "satisfaction" than the men did. Both men and women, however, rated lunches labeled "Low Fat/Low Calorie" less rich even when the food was actually full fat -- indicating that they really couldn't tell the difference.
"Even though we expected the fat and calorie conscious females to be more responsive to written and verbal cues, it was the males who paid attention to the labels," said study director S.E. Specter, assistant professor of nutrition.
Specter said one reason the men probably were more influenced by the labels is because paying attention to fat and calorie content was a new behavior for them.
Specter worked with doctoral student Julia A. Ello on the study, which involved 21 males and 22 females and was representative of the typical young male who's not interested in low fat/low calorie foods and the young women who are. The study was also the first of its type to involve foods normally eaten in which the calorie content was halved in the low-fat versus the visually-identical high-fat lunch.
Hunger reported in the afternoon did not differ for males, regardless of what they had for lunch. However, snack intakes for male but not female subjects were significantly higher after lunches labeled "Low Fat/Low Calorie," regardless of actual fat/calorie content.
"The data suggest that cognitive cues such as label information can influence subjective ratings, including 'liking,' 'satisfaction' and hunger, for both genders," Specter said. "Label information, at one meal, also influenced the male subjects to shift their subsequent snack intakes.
"Female subjects, however, ignored the cognitive cues in the label information as well as the physiological cues from the calorie content of the lunch which was twice as high in the high-fat version. The women appear to have been relying on visual cues, such as portion size, guided by a preconceived view of how much they thought they ought to be eating," he said.
While taking a giant leap toward solving one of the greatest mysteries of astronomy, NASA's Chandra X-ray Observatory also may have revealed the most distant objects ever seen in the Universe and discovered two puzzling new types of cosmic objects.
Not bad for being on the job only five months.
Chandra has resolved most of the X-ray background, a pervasive glow of X-rays throughout the universe, which was first discovered in the early days of space exploration. Before now, scientists have not been able to discern the origin of the hard, or high-energy, X-ray background, because until Chandra no telescope has had the technology to resolve it.
This and other discoveries have been made with Chandra's Advanced CCD Imaging Spectrometer (ACIS). The ACIS X-ray camera was conceived and developed for NASA by Penn State and the Massachusetts Institute of Technology under the leadership of Gordon Garmire, Evan Pugh professor of astronomy and astrophysics.
"This is a major discovery," said Alan Bunner, director of NASA's Structure and Evolution of the Universe science theme. "Since it was first observed 37 years ago, understanding the source of the X-ray background has been a Holy Grail of X-ray astronomy. Now, it is within reach."
"Chandra's sensitivity is 20 times better than achieved with the best previous X-ray telescopes," said Garmire. "This sensitivity, plus the superior spatial resolution of Chandra's mirrors, make Chandra the perfect tool for studying this faint X-ray source in its crowded field."
One-third of the sources are galaxies whose cores shine bright in X-rays, yet do not shine in visible light. There may be tens of millions of these "veiled galactic nuclei" in the universe, each likely harboring a massive black hole at its core.
A second new class of objects is assumed to be "ultra-faint galaxies." Richard Mushotzky of NASA's Goddard Space Flight Center said that these sources may emit little or no optical light, either because the dust around the galaxy blocks the light totally or because the optical light is eventually absorbed during its long journey across the universe.
In the latter scenario, Mushotzky said that these sources would be well over 14 billion light years away and thus the earliest, most distant objects ever identified.
Other discoveries made using Chandra include nearly a thousand faint X-ray-emitting stars in a single observation of young stars in the Orion Nebula. The discovery is the richest field of X-ray sources ever obtained in the history of X-ray astronomy.
"This Chandra image is a milestone in the field -- the first time X-ray astronomy has resolved individual massive stars still embedded in their natal cloud," said Garmire.
The discovery of such a wealth of X-ray stars in the closest massive star-forming region to Earth (only 1,500 light years away) is expected to have a profound impact on our understanding of star formation and evolution.
To follow Chandra's progress, visit Chandra's Web sites at http://chandra.nasa.gov/ and http://chandra.harvard.edu.
Researchers in the College of Medicine have identified a new gene that may help cancer patients. There are an estimated 60,000 to 100,000 genes in the human body.
"Opioid Growth Factor (OGF), also known as Met-enkephalin, is a naturally occurring peptide in the body that helps regulate cell growth," said principal investigator Ian Zagon, professor of neuroscience and anatomy. "What we have discovered during animal and human testing is that OGF slows the growth of a variety of human tumors and dramatically reduces the spread of cancer cells. When it slows things down enough, the body's own immune system can fight the cancer cells."
The information discovered by Zagon and his colleagues will be vital to designing more powerful and long lasting anti-tumor agents, and in understanding the origins of cancer.
"We know that OGF naturally occurs in the body, and it normally regulates cell replication. By giving patients OGF, we are really using the body's own natural mechanisms to fight cancer. This approach is an alternative to using toxic chemicals to kill cancer cells and often making the patient very sick," said Zagon.
Zagon and other physicians at Hershey Medical Center are currently administering OGF to patients with pancreatic cancer as part of a phase one clinical trial. The medical center is the only site where this trial is occurring.