Washington University
A recently developed mouse model of brain tumors common in the genetic disorder neurofibromatosis 1 (NF1) successfully mimics the human condition and provides unique insight into tumor development, diagnosis and treatment, according to researchers at Washington University School of Medicine in St. Louis. After validating their animal model, the team made two important discoveries: New blood vessels and immune system cells may be essential to the initial formation of tumors and therefore may be promising drug targets; and brain images often used to determine the need for treatment may not actually be diagnostically informative.
Mice missing a specific protein from their brains react to stress differently. The genetically engineered mice develop an imbalance in a hormone involved in stress responses, and during stressful situations, they behave as if they are depressed. Genetic variations in the same protein may be a significant cause of human depression, according to researchers at Washington University School of Medicine in St. Louis.
Almost 60 years after it was conceived, Washington University orthopaedic surgeon Matthew B. Dobbs, MD, has revived a nonsurgical technique to correct talipes equinovarus, or clubfoot, a congenital foot deformity. By combining the venerable procedure with the latest genetic science and translational research, Dobbs aims to drastically improve treatment and perhaps eventually reduce the incidence of the malady.
Babies who never sleep on their stomachs don't learn behaviors that may lessen their risk of sudden infant death syndrome (SIDS), researchers at Washington University School of Medicine in St. Louis have found. Even so, the researchers caution that infants should always be placed on their backs to sleep. ''The first few times babies who usually sleep on their backs or sides shift to the prone (lying face down) position, they have a 19-fold increased risk of sudden death,'' says senior author Bradley T. Thach, M.D., a Washington University pediatrician at St. Louis Children's Hospital.
In a six-month study of elderly people, researchers at Washington University School of Medicine in St. Louis found that the hormone dehydroepiandrosterone (DHEA) significantly reduced abdominal fat and improved insulin action. This finding suggests that DHEA may be able to counter the increase in abdominal fat and accompanying increased risk for diabetes that very often occurs as we grow older.
The microorganisms that normally live in the gut can increase body fat, say researchers at Washington University School of Medicine in St. Louis. They found that gut microbes can open the ''gates'' fat uses to enter the body's fat cells. Using a two-pronged strategy, gut microbes first break down otherwise indigestible dietary components, effectively increasing the amount of calories we can harvest; then they promote fat storage from the harvested calories.
Severe calorie restriction prevents certain aging-related changes in the brain, including the accumulation of free radicals and impairments in coordination and strength, according to a mouse study at Washington University School of Medicine in St. Louis. However, the dietary changes did not seem to prevent mice from developing some cognitive deficits associated with age, such as declines in memory.
A minimally invasive approach to curing the most common heart rhythm abnormality, atrial fibrillation, takes half the time of the traditional surgical procedure but is equally effective, according to research at Washington University School of Medicine in St. Louis. ''Our findings show that this technique is much easier to perform but works just as well as the more invasive approach.''
To stick to cells in the respiratory tract and start an infection, the bacterium Haemophilus influenza has to secrete a glue-like protein. Researchers at Washington University School of Medicine in St. Louis report this week that a study of the valve that lets out the glue has produced some surprising information.
Millions of people with severe tinnitus currently have little hope for quick relief from the unrelenting ringing or buzzing noises the disorder produces. But scientists at Washington University School of Medicine in St. Louis suspect a drug already approved for seizure disorders and chronic nerve pain also can help silence the noises that plague tinnitus patients. The team is recruiting volunteers for the first large study of the potential treatment. ''All other medications currently used for this condition just work on the negative effects of tinnitus, like sleep disturbance and anxiety. But if this trial is successful, it could lead to a new type of treatment option.''
Removal of an immune system signaling protein prevents the development of a lupus-like condition in mice, researchers at Washington University School of Medicine in St. Louis and the National Institutes of Health have found. If additional studies in other animal models and humans confirm that SLAM-associated protein (SAP) is a primary contributor to lupus, it may be an ideal target for the development of new drug treatments, scientists said.
Liposuction is no substitute for dieting when it comes to preventing diabetes, hypertension and heart disease, according to researchers at Washington University School of Medicine in St. Louis.
Reporting in the June 17 issue of The New England Journal of Medicine, the Washington University team found that removing abdominal fat by using modern liposuction techniques did not provide the metabolic benefits normally associated with similar amounts of fat loss induced by dieting.
The idea that dying people hang on to life in order to celebrate one more birthday or holiday lacks any scientific basis, say scientists who reviewed two decades' worth of research. ''The studies published to date have not convincingly established that death can be postponed through force of will or hastened by the loss of the desire to live,'' say Judith A. Skala, R.N., Ph.D., and Kenneth E. Freedland, Ph.D., of Washington University School of Medicine.
A possibly important ally of the immune system that can help with the tricky task of separating friend from foe has been identified by scientists. Researchers showed that a protein known as H2-DM can keep immune system T cells from erroneously assaulting the body's own tissues. Distinguishing between foreign and native is one of the immune system's most important tasks; failure to make this distinction can lead the immune system to attack the body, causing autoimmune conditions like diabetes, lupus, arthritis and multiple sclerosis.
International research teams studying two distinct populations have found variants in a gene that may predispose people to type 2 diabetes, the most common form of the disease. "This is an outstanding example of how scientists are using the tools of modern biology to understand the causes of our nation's most common--and most devastating--diseases," said Dr. Elias A. Zerhouni, Director of the National Institutes of Health (NIH). "As researchers continue to build upon the foundation laid by the Human Genome Project, we can expect even swifter progress in our effort to understand, treat and eventually prevent many complex conditions such as diabetes, heart disease and mental illness."
