For the complete stories on this research, click on the title of each summary.
Yale team finds tiny trigger for key chemical structure
Yale chemist Scott Miller and his team have developed a simple catalyst that triggers the creation of chemical structures with a difficult-to-make form of chirality, or handedness. Whether molecules are “right-handed” or “left-handed” impacts how they behave, such as in the case of thalidomide, a sedative prescribed in the 1950s that caused severe birth defects in part because it contained both right- and left-handed molecules. Now Miller has discovered an efficient catalyst comprised of a mere three amino acids that creates single-handed structures called atropisomers, a particular molecular architecture apparent in many biologically active substances, including the antibiotic vancomycin.
Prions, not plaques, cause memory loss in mice with Alzheimer’s
Common prion proteins — not the amyloid plaques usually associated with Alzheimer’s disease — seem to be the culprit in memory loss in mice with a form of the dementia, Yale researchers report in the journal Neuroscience. The findings support the thesis that the plaques themselves are not the cause of memory loss in Alzheimer’s disease, but are a side effect of the disease process. “Cellular prion protein is the essential mediator in Alzheimer’s that leads to memory dysfunction and reduced survival in mice,” says Stephen Strittmatter, the Vincent Coates Professor of Neurology, professor of neurobiology and senior author of the study.
Breast milk protein linked to poorer breast cancer survival
In a study that sheds light on why breast cancer may be deadlier for pre-menopausal women, a Yale School of Medicine team has linked breast cancer survival with levels of a transport protein that regulates milk production in mammary glands. The paper was published in the online early edition of the Proceedings of the National Academy of Sciences. A team led by Dr. John Wysolmerski, professor of endocrinology at Yale School of Medicine and a member of the Yale Medical Group and Yale Cancer Center, showed that high levels of this transport protein after lactation stops allow malignant cells to avoid cell death. Further, the researchers associated these high levels with poorer outcomes in breast cancer — larger tumors, more lymph node involvement, worse survival and more HER2-positive status. HER2 is a protein that indicates greater aggressiveness in breast cancer. HER2-positive tumors are more common among younger women.
Pervasive weight discrimination a serious health risk
Weight discrimination poses serious risks to the psychological and physical health of obese individuals and should be considered a social justice issue as well as a public health priority, according to a paper from the Rudd Center for Food Policy and Obesity at Yale. The paper appeared in the June issue of the American Journal of Public Health. Authors Rebecca M. Puhl, research scientist in psychology, and Chelsea A. Heuer, research associate, argue that despite decades of studies documenting weight stigma and discrimination toward obese people, these attitudes remain pervasive and their public health implications are still largely ignored. The authors challenge the notion that weight stereotypes and stigmatization motivate individuals to adopt healthier behaviors, citing evidence that they do just the opposite — increasing the risk of unhealthy eating behavior and the avoidance of physical activity. Despite five decades of scientific research documenting the consequences of weight stigma, no federal legislation exists to protect obese individuals from weight-based discrimination, and creating such legislation would improve their health, say Puhl and Heuer.
Heart failure deaths in hospitals drop but readmission rates rise
Heart failure patients are being discharged faster, but the incidence of out-of-hospital deaths and readmissions has increased, Yale School of Medicine researchers report in the Journal of the American Medical Association. The findings suggest that many patients are discharged before they are ready without the medical support they need to transition from hospital to home, according to lead author of the study Dr. Harlan M. Krumholz, the Harold H. Hines Jr. Professor of Medicine and Epidemiology and Public Health. Krumholz and his co-authors conducted an analysis of Medicare data from 1993 through 2006 of older patients hospitalized for heart failure. They found that during that time, the average length of stay decreased from 8.8 days to 6.3 days; in-hospital mortality decreased from 8.5% to 4.3%; and the 30-day mortality rate decreased by 2.1%. During this period, 30-day hospital readmission rates increased from 17.2% to 20.1%, and discharge to skilled nursing facilities increased from 13% to 19.9%. Krumholz said the current model of care for older heart failure patients might benefit from more attention to the care and outcomes in the early period after hospital discharge, and routine surveillance of how changes in practice affect patient outcomes.
Children can be taught to manage Tourette syndrometics
Yale School of Medicine researchers and their colleagues have used a non-medication behavioral intervention to reduce chronic tics in children and adolescents with Tourette syndrome (TS). The team found that a specialized form of behavior therapy called Comprehensive Behavioral Intervention for Tics (CBIT) reduced tics in a sample of 126 subjects. The results of the multi-site study, conducted by investigators at Yale and several other leading U.S. medical centers, are published in the May 19 issue of the Journal of the American Medical Association. TS has historically been treated with antipsychotic medications, which reduce tics, but have side effects that often limit their usefulness in children. In CBIT, children learn to recognize when a tic is about to occur and to engage in an alternative voluntary action until the unwanted sensation passes. Parents are taught ways to promote these management strategies in their children. “This is an important study because it expands the range of clinicians who can treat this condition — medication is no longer the only treatment,” says Lawrence Scahill, a professor at the Yale Child Study Center and the School of Nursing.
Yale team discovers new molecular scissors that cut the tiniest genes
A team of Yale scientists has discovered a previously unknown type of molecular scissors that can tailor micro-RNAs, tiny snippets of genetic material that play a key role in regulating many of life’s functions. The team also found that the absence of these molecular scissors, or the micro-RNAs they create, could trigger anemia in mice and in zebrafish. Their report appears online in the May 6 issue of Science Express. The findings provide a new method to discover new families of micro-RNAs that influence many different types of biological activity, says Antonio J. Giraldez, the Lois and Franklin H. Top Jr. Yale Scholar in the genetics department of the Yale School of Medicine.
Gender and family status have powerful effect on surgical career choices
Gender, marital status and children appear to play a powerful role in influencing the careers of surgical residents, according to a new survey by researchers at Yale School of Medicine. The study appears in the May issue of Archives of Surgery, a publication of the American Medical Association. More than 55% of those surveyed believed that a surgeon must receive specialty training in order to be successful, but far fewer women than men felt that way. In addition, far fewer married residents than single ones felt that specialization was necessary, as did far fewer of those who already had children. The more children a resident had, in fact, the less likely he or she was to believe that specialty training is the key to success as a surgeon, notes lead author Dr. Julie Ann Sosa, associate professor of endocrine surgery and surgical oncology.
Childhood asthma found to negatively affect adult health
Children with asthma are more likely to develop a range of health and social problems as they enter into adulthood, new research by the Yale School of Public Health has found. The study is published in this month’s issue of the Journal of Health Economics.
Researchers found significant long-term consequences for children who suffer from the chronic breathing condition, including an increased likelihood of adult obesity and increased absenteeism from either school or work. “The long-term health effects of childhood asthma appear to be as severe as those associated with other major childhood health conditions such as ADHD or low birth-weight,” says lead author Jason M. Fletcher.
Poll: American opinion on climate change warms up
After a recent dip, the American public is becoming more concerned about global warming again. A national survey by researchers at the Yale Project on Climate Change Communication (YPCCC) found that, since January, public belief that global warming is happening rose four points, to 61%, while belief that it is caused mostly by human activities rose three points, to 50%. Research scientist Anthony Leiserowitz of the YPCCC credits the rebound in public opinion with signs of economic recovery and fading memories about climate change science scandals and unusually cold winter weather.
Astronomers witness a star being born
Yale astronomers have glimpsed what could be the youngest known star at the very moment it is being born. Not yet fully developed into a true star, the object is in the earliest stages of formation and is located in the Perseus star-forming region, about 800 light years away within our Milky Way galaxy. Postdoctoral associate Xuepeng Chen and Héctor Arce, assistant professor of astronomy, think the object is in between the prestellar phase, when a particularly dense region of gas and dust first begins to clump together, and the protostar phase, when gravity has pulled enough material together to form a dense, hot core out of the surrounding envelope.
Scientists create 3D models of whole mouse organs
Yale engineers have for the first time created 3D models of whole intact mouse organs, a feat they accomplished using fluorescence microscopy. Combining an imaging technique called multiphoton microscopy with “optical clearing,” which uses a solution that renders tissue transparent, the researchers were able to scan the organs and create high-resolution images of the brain, small intestine, large intestine, kidney, lung and testicles. They then created 3D models of the complete organs — a feat that, until now, was only possible by slicing the organs into thin sections or destroying them in the process, and which could improve the way doctors study patient biopsies.
In the bacterial world, genetic messengers work close to home
In a fundamental shift in the view of how bacteria proliferate and survive, Yale scientists have discovered that most of the genetic action within bacteria takes place close to home. Since bacteria lack internal compartments such as a nucleus, scientists had long assumed that the workings of messenger RNA, which translate the genetic information contained within DNA into proteins, occurred randomly throughout the entire cell. Christine Jacobs-Wagner, the Maxine F. Singer Professor of Molecular, Cellular and Developmental Biology, and her team identified many different mRNAs within bacteria as well as precisely where in the cell this genetic activity was taking place, and found that messenger RNAs are not nomads at all, but homebodies staying close to the genes from which they arise. The findings could have implications for understanding human disease.
A mountain bird’s survival guide to climate change
Yale researchers have found that mountain birds’ risk of extinction due to global warming is greatest for species that occupy a narrow range of altitude, and that their vertical distribution better predicts this risk than the temperature change they experience. Walter Jetz, associate professor of ecology and evolutionary biology, and postdoctoral associate Frank La Sorte studied 1,000 species of birds living in high-elevation environments, which respond to warming temperatures by shifting to higher and cooler elevations. They discovered that if they live in isolated places and are unable to relocate, a full third of mountain bird species will be severely threatened by global warming.
Colors of butterfly wing yield clues to light-altering structures
At the very heart of some of the most brilliantly colored butterfly wings lie bizarre structures, a multidisciplinary team of Yale researchers has found. The crystal nanostructures that ultimately give butterflies their color are called gyroids — “mind-bendingly weird” three-dimensional curving structures that selectively scatter light, explains Richard Prum, the William Robertson Coe Professor of Ornithology, Ecology and Evolutionary Biology. The structures intrigue the team’s scientists and engineers, who are now studying ways to use them to harness the power of light. In particular, photonic engineers are using gyroid shapes to try to create more efficient solar cells and, by mimicking nature, may be able to produce more efficient optical devices as well.
Yale researchers awarded $3.5 million to study hepatitis C
Anna Marie Pyle, the William Edward Bilbert Professor of Molecular Bioiphysics, and Brett Lindenbach, assistant professor of microbial pathogenesis, have received a $3.5 million grant from the National Institutes of Health to study hepatitis C, a deadly virus that attacks the liver and afflicts about 170 million people worldwide, including nearly 2% of the U.S. population. Current treatments for the disease are poorly tolerated and effective in only a minority of patients. The researchers will use the money to study the molecular underpinnings of hepatitis C, dissecting the critical features of viral replication in the hopes of laying the groundwork for a new generation of therapies.
Electrical fields influence brain activity
Most scientists think electrical fields in the brain are the by-products of neuronal activity. Now David McCormick, the Dorys McConnell Duberg Professor of Neurobiology, and Flavio Frohlich have shown that electrical fields can actually influence the activity of brain cells. The researchers introduced slow oscillation signals into brain tissue and found that they created a kind of feedback loop, with changes in the electrical field guiding neural activity, which in turn strengthened the electrical field. The finding helps explain why techniques that influence electrical fields, such as deep brain stimulation, are effective in treating various neurological disorders, and could lead to better treatment for epilepsy, depression and other neural dysfunctional states.
Sweeping changes recommended for American diet
In the face of soaring obesity rates in the U.S., a national dietary advisory committee of 13 national experts, including Rafael Pérez-Escamilla, professor of epidemiology and public health, recommends sweeping changes to the American diet, including a reduction in overall calorie consumption, a reduction in sodium and added sugars, and an increase in seafood and plant-based foods. Federal nutrition guidelines are updated every five years and influence existing food assistance programs such as school lunches and food stamp and industry regulation.
Americans support laws to prohibit weight discrimination
American adults are in favor of legislation to prohibit weight discrimination, particularly in the workplace, according to a new study. Researchers from Yale’s Rudd Center for Food Policy and Obesity found considerable public support for workplace laws to prevent employers from refusing to hire, denying promotions to, assigning lower wages to, or terminating qualified obese employees based on their weight.
Licensed characters on food packaging affect kids’ taste preferences
Children significantly prefer the taste of junk foods branded with licensed cartoon characters on the packaging compared with the same foods without characters, finds a new study from Yale’s Rudd Center for Food Policy and Obesity. Results indicated that children were significantly more likely to prefer the taste of the low-nutrient, high-energy foods such as graham crackers and gummy fruit snacks when a licensed cartoon character appeared on the package. The study also found that children were significantly more likely to choose any of the licensed character-branded food items for snacks than those in packages without characters.
$5 million grant to study genetic origins of brain tumors
Elizabeth B. Claus, professor of epidemiology and public health, will head a new $5 million study funded by the National Institutes of Health to identify genes associated with meningioma, the most frequently reported primary intracranial tumor in the United States, which affects thousands of people each year. The study will enroll thousands of people in an attempt to pinpoint the genetic origins of meningioma tumors, which form in the tissue that covers the brain and spinal cord, called the meninges. The tumors can grow to a very large size, causing seizures, loss of vision and weakness in limbs.
For Type 1 diabetics, pump therapy is better than daily injections
A year-long clinical trial by Yale University and other institutions showed that treatment with sensor-augmented insulin pumps, which include a system of continuous glucose monitoring, leads to significantly greater control of type 1 diabetes than a daily regimen of multiple insulin injections. Improved glycemic control can reduce the complications associated with type 1 diabetes, but maintaining that control is challenging, particularly for children. According to William Tamborlane, professor and section chief of pediatrics (endocrinology),”Combining insulin pumps and continuous glucose monitoring can help patients safely reach their goal of glycemic control, while minimizing the risk of severe hypoglycemia and weight gain.”
Studies highlight need for comprehensive HIV approach in Malaysian prisons
Two studies by Yale and the University of Malaya highlight the multitude of problems faced by HIV-infected prisoners in Malaysia, where 6% of the prison population suffers from the disease. Frederick L. Altice, professor of internal medicine, examined the association between HIV infection, mental illness and substance abuse among prison inmates and found that a public health approach that simultaneously addresses all three conditions is needed in both the correctional and community settings in order to provide adequate care for patients and to help prevent them from returning to prison. In the second study, a team also led by Altice examined the community re-entry challenges faced by HIV-infected prisoners in Malaysia, and recommended targeted interventions such as effective drug treatment, HIV care and public awareness campaigns.
