Brain & Behavior

Radiation, injections turn on immune system to attack brain tumor cells

Researchers are working to develop a non-surgical approach to brain cancer that uses radiation and the injection of specially cultured bone marrow cells into the tumor. The combination sets in motion a local and systemic immune response to kill surviving tumor cells. The novel approach has provided promising results in a study on rats, described in the March 3 issue of the Journal of Immunotherapy. Human trials are expected to begin within the year.

Alcohol researchers relate a genetic factor to anxiety in women

Researchers have identified a genetic factor that appears to influence anxiety in women. Combining DNA analysis, recordings of brain activity, and psychological tests, investigators at the National Institute on Alcohol Abuse and Alcoholism (NIAAA) found that Caucasian and American Indian women with the same gene variant had similarly high scores on tests that measure anxiety. These women also had similar electroencephelograms (EEG) — recordings of brain electrical activity as unique as an individual’s fingerprints — that showed characteristics of anxious temperament, further strengthening the association of this shared genetic factor with anxiety. The study appears in the current issue of the journal Psychiatric Genetics.

Screening test can help identify cancer survivors at risk for emotional distress

A relatively brief screening test can give caregivers a good indication of which cancer survivors are emotionally distressed and may benefit from further psychological evaluation, according to new research by a team of Dana-Farber Cancer Institute investigators. In a study in the March 1 issue of the Journal of Clinical Oncology, the researchers found that childhood cancer survivors whose screening scores indicated they were dissatisfied with their physical appearance, were in poor physical health, or had been treated with head radiation had an increased risk of experiencing psychological distress.

New Insights Revealed about Stresses Between Sliding Grains

Densely packed granular particles that inch past each other under tension interact in ways more complex and surprising than previously believed, two Duke University physicists have discovered. Their observations, described in the Thursday, February 27, 2003, issue of the research journal Nature, could provide new insight into such geophysical processes as the behavior of a slowly moving glacier or an active earthquake fault, said Robert Behringer, a Duke physics professor who is one of the Nature article’s authors. The physicists’ findings could also have implications for industrial problems, such as how the contents of a hopper holding granular materials such as grain or coal flow, he added.

Obese people experience delay in feeling full, study finds

Most people feel full about 10 minutes after they begin eating, but for those who are obese, it may take almost twice as long for their brains to get the message, according to researchers at the University of Florida’s Evelyn F. and William L. McKnight Brain Institute. Through innovative use of neuroimaging, UF scientists successfully pinpointed when the brain responds to changing hormone levels in the body that signal satiety. The finding raises the possibility that a delayed feeling of fullness or the inability to feel satisfied while eating could perpetuate obesity, making treatment difficult, they report in the February issue of Psychiatry Annals.

Xenon Shows Promise in Protecting Brain During Bypass Surgery

In studies using rats, researchers from Duke University Medical Center and the Imperial College, London, have found evidence that the chemically inert gas xenon can protect the brain from the neurological damage often associated with the use of the heart-lung machine during coronary artery bypass surgery. The researchers say that xenon appears to block receptors on nerve cells in the brain that can be “overstimulated” in response to the surgery. This overstimulation can lead to nerve cell damage or death.

Santillan Dies at Duke Hospital

Following a series of tests, doctors at Duke University Hospital determined that Jesica Santillan, 17, meets the criteria for the declaration of brain death. She was pronounced dead at 1:25 pm today (Feb. 22). “All of us at Duke University Hospital are deeply saddened by this,” said William Fulkerson, M.D., CEO of the hospital. “We want Jesica’s family and supporters to know that we share their loss and their grief. We very much regret these tragic circumstances.”

Pavlov?s Flies: Researchers Identify Fruit Fly Memory Mutants

By teaching fruit flies to avoid an odor and isolating mutant flies that can?t remember their lessons, researchers at Cold Spring Harbor Laboratory in New York have identified dozens of genes required for long-term memory. In the same study, using DNA chip technology, the scientists identified another large group of candidate memory genes that are either switched on or off in the fly brain during memory formation.

Scientists locate, characterize key hormone involved in appetite control

Researchers have identified a key hormone involved in appetite control and demonstrated its effect on the brain. Scientists have shown that the hormone, called ghrelin, activates specialized neurons in the hypothalamus involved in weight regulation. Researchers believe this information could be used to develop drugs aimed at stimulating appetite in patients who have undergone extreme weight loss due to illness, a condition known as cachexia. Conversely, drugs aimed at limiting production of the hormone might be developed to reduce appetite for those battling severe obesity.

Fly mutation suggests link to human brain disease

Greater insight into human brain disease may emerge from studies of a new genetic mutation that causes adult fruit flies to develop symptoms akin to Alzheimer’s disease. “This is the first fruit fly mutant to show some of the outward, physical manifestations common to certain major human neurodegenerative diseases,” said principal investigator Michael McKeown, a biology professor at Brown University. A research team found the mutation in a gene they named “blue cheese.”