Vanderbilt University
Patients who undergo radiation for treatment of brain tumors may survive their cancer only to have lasting memory and learning deficiencies, the impact of which can be particularly devastating for children. Now, researchers have discovered that lithium, a drug commonly used to treat bipolar disorder and other mental illnesses, can protect the brain cells involved in learning and memory from radiation damage. While the work has been conducted in cell culture and animal studies thus far, clinical trials are expected to be conducted soon to test whether the drug can protect humans from cognitive deficits as a result of cranial radiation therapy.
Marijuana use may increase the risk of ectopic (tubal) pregnancies, researchers at Vanderbilt University Medical Center reported this week. The researchers studied CB1, a ''cannabinoid'' receptor that binds the main active chemical for marijuana, delta-9-tetrahydrocannabinol (THC). In pregnant mice that lacked the gene for the receptor, or in which the receptor was blocked, the embryo failed to go through the oviduct -- the tube leading from the ovaries to the uterus. The same thing happened in normal mice when the receptor was over-stimulated.
Babies as young as five months old make distinctions about categories of events that their parents do not, revealing new information about how language develops in humans. ''It's been shown in previous studies that adults actually categorize things differently based on what language they speak.... So, if language is influencing adults' thought, one of our questions was, what's going on with preverbal infants? Do children think before they speak?"
Bill Turner never knew that drinking a popular soda could adversely affect his recovery from a double-lung transplant. What ensued was a true medical mystery, leading to the identification of a new food and drug interaction. It took a team of medical sleuths at Vanderbilt University Medical Center to get to the bottom of what was causing the 35-year-old to have abnormal blood chemistries during a post-transplant check up.
Scientists have discovered the region of the brain responsible for the old adage, "out of sight, out of mind." The amount of information we can remember from a visual scene is extremely limited and the source of that limit may lie in the posterior parietal cortex, a region of the brain involved in visual short-term memory, researchers say. "Visual short-term memory is a key component of many perceptual and cognitive functions and is supported by a broad neural network, but it has a very limited storage capacity."
An international team of chemists has developed a new family of antioxidants that are up to 100 times more effective than Vitamin E. Antioxidants are molecules that can counteract the damaging effects of oxygen in tissues and other materials. So far, the new antioxidants have been tested "in vitro" ? in the test tube. But studies with biological molecules, such as cholesterol, suggest that the new compounds have properties that could make them suitable for dietary supplements. Shortly, Vanderbilt researchers expect to begin the lengthy process of determining how effective the new the compounds are in living animals and whether they have any harmful side effects.
Today, we know a little bit more about one of mankind's deadliest enemies, the mosquito. Scientists have taken an important step toward understanding the mosquito's sense of smell, an avenue of research that may lead to better ways to repel the deadly insect. In a joint effort, researchers at Vanderbilt and Yale universities have verified that the antennae of female Anopheles mosquitoes that prey on humans contain receptors that respond to one of the chemical compounds found in human sweat.
Investigatorshave identified a type of DNA damage caused by chronic inflammation as a potential risk factor for colorectal cancer. The findings, published this week in the early online edition of the website of the Proceedings of the National Academy of Science, shed more light on the role that inflammation might play in cancer and suggests that measurement of this type of DNA damage might be useful in assessment and management of a patient?s colorectal cancer risk.
Bigger and brighter isn't better, at least not when trying to view moving objects. That is the counter-intuitive result of a study performed by a team of Vanderbilt psychologists which sheds new light on one of the most sophisticated processes performed by the brain: identifying and tracking moving objects. "The bigger an object, the easier it is to see. But it is actually harder for people to determine the motion of objects larger than a tennis ball held at arms length than it is to gauge the motion of smaller objects," says Duje Tadin, first author of the paper on the study appearing in the July 17 issue of the journal Nature.
Tumor cells have evolved a crafty scheme for protecting themselves from the killing power of the host immune system; in part, they disable the immune response. New studies implicate a receptor for prostaglandin E2 (PGE2) in this phenomenon of tumor-induced immune suppression. The findings, published in the March 1 Journal of Clinical Investigation, suggest that drugs that block the PGE2 receptor, called EP2, might restore the immune system's tumor-killing capacity.
A team of scientists has shrunk tumors or delayed their growth in animal studies by using radiation to enable a drug to "zero in" and block the tumor blood vessels. The work, reported in the January issue of the journal Cancer Cell, is a model for what might be achieved in patients by using radiation to activate drug targets in tumors. "We can now use combinations of chemotherapy and radiation to improve the anti-cancer effect for many of our patients, but the side effects can be great," said Dr. Dennis Hallahan, chair of Radiation Oncology at Vanderbilt- Ingram. "With this approach, we hope we can ultimately deliver drugs directly and selectively to the tumor alone, and reduce side effects."
Forget the robot child in the movie ?AI.? Vanderbilt researchers Nilanjan Sarkar and Craig Smith have a less romantic but more practical idea in mind. ?We are not trying to give a robot emotions. We are trying to make robots that are sensitive to our emotions,? says Smith, associate professor of psychology and human development.
Their vision, which is to create a kind of robot Friday, a personal assistant who can accurately sense the moods of its human bosses and respond appropriately, is described in the article, ?Online Stress Detection using Psychophysiological Signals for Implicit Human-Robot Cooperation.? The article, which appears in the Dec. issue of the journal Robotica, also reports the initial steps that they have taken to make their vision a reality.
Physicians treating deadly liver tumors are finding success by injecting patients with radioactive microspheres that get trapped in the web of small blood vessels feeding a tumor and zap the cancerous cells. "The liver doesn't tolerate external beam radiation in sufficient doses to affect tumor without damaging the remaining good liver," said one physician researcher working on the treatment. "These spheres emit radiation for a short distance, less than a centimeter. If you can cluster radiation right around the tumor, the radiation exposure at the tumor site compared to normal liver is favorable."
An international research consortium has launched an approximately $100 million public-private effort to create the next generation map of the human genome. Called the International HapMap Project, the new venture is aimed at speeding the discovery of genes related to common illnesses such as asthma, cancer, diabetes and heart disease.
