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Scientists are still trying to piece together why our hearing goes downhill with age, with the goal of trying to slow it or even reverse it. When it comes to the cocktail party problem, the dimmer switch is a piece of that story, though it's not clear just how big a factor.

I think it's a significant player, said Robert Frisina of the University of Rochester in New York, who is studying it. Frisina and colleagues published evidence in 2002 that the dimmer switch effectiveness declines with age. The drop-off showed up in middle-aged people (ages 38 to 52) and was even worse in people past age 62.

Chemicals that interfere with the male hormone system are so common — and so potentially damaging — that the government should stop studying them one by one and consider their combined effect, an expert panel said Thursday.

The Environmental Protection Agency typically studies the impact of these and other chemicals individually. But that approach may underestimate the effect of being exposed to many different chemicals with similar effects, says the University of Rochester School of Medicine and Dentistry's Deborah Cory-Slechta, chairwoman of the committee that wrote the report.

Congratulations to Ania Majewska, Ph.D. on being named a Kavli Fellow by the National Academy of Sciences (NAS). Each year the NAS conducts the Kavli Frontiers of Science Symposium with some 100 of the best and brightest of young American scientists attending to hear, discuss, and debate talks across a wide range of the natural sciences. Thus, many of the country's ablest scientists--those now rising to positions of leadership in their institutions and their professions--have gone through a seminar on the value and potential of interdisciplinary research. Attendees are selected from a pool of young researchers who have made significant contributions to science.

Not only is the University of Rochester the region's largest employer - it's also one of the best places in the nation for scientists to work, according to The Scientist magazine.

It's gratifying to be recognized for the research environment that we've worked hard to create, said Bradford C. Berk, M.D., Ph.D., CEO of the Medical Center. This is an institution founded on the principle of interdisciplinary collaboration. Our scientists' satisfaction plays an important role in the ultimate success of our research enterprise, and helps us truly achieve Medicine of the Highest Order.

Maiken Nedergaard, M.D., D.M.Sc., has been elected a member of the Royal Danish Academy of Sciences, the premier scientific society in Denmark. The society elects only six new members worldwide every other year.

Nedergaard has been a pioneer in brain research, demonstrating that brain cells known as astrocytes play a role in a host of human diseases. For decades, much of the attention of neuroscientists had been focused on brain cells known as neurons, which send electrical signals. Astrocytes were long considered cells whose primary function was to support the neurons.

Nedergaard has turned that notion on its head, showing that astrocytes themselves play an important role in epilepsy, spinal cord disease, migraine headaches, stroke, and Alzheimer's disease.

The GEBS summer scholars program is designed for Undergraduate students interested in the Ph.D. degree in the Biological or Biomedical Sciences and students with a potential interest in attending graduate school at the University of Rochester. Students choose from a list of mentors and fill out an application.

Xiaohai Wang, M.D., Ph.D., a former student in the Neuroscience Graduate Program, has received the Robert Doty Award of Excellence in recognition of outstanding dissertation research in neuroscience. He received his M.D. from China Medical University, Shenyang, Liaoning, China in 1999, and then worked as an instructor in the Department of Histology & Embryology at the same university until 2002 when he moved to the United States to begin Ph.D. studies in Neuroscience at New York Medical College.

Dr. Wang joined Dr. Maiken Nedergaard's laboratory for his thesis work. Dr. Wang's dissertation entitled Role of astrocytic Ca²⁺ signaling in response to sensory stimulation in vivo demonstrated that astrocytes can mediate slow sensory adaptation through Ca²⁺ dependent release of adenosine. During his tenure as a graduate student, Dr. Wang co-authored a very impressive nine publications with Dr. Nedergaard, including two first author papers in Nature Neuroscience and Nature Medicine. After graduation, he accepted a position as Senior Research Biologist at Merck Research Laboratories.

Dr. Robert Doty was a leading brain researcher who helped create what is now the world's largest organization of neuroscientists, the Society for Neuroscience. Dr. Doty had served the University of Rochester School of Medicine and Dentistry since 1961, a central figure to a team of people that has made the University an internationally recognized powerhouse in neuroscience.

How our brain controls our movements is a bit more complex and varied than scientists have previously recognized, according to research recently published in Science by a team of scientists and physicians at the University of Rochester Medical Center.

The team led by neurologist Marc Schieber, M.D., Ph.D., professor of Neurology and of Neurobiology & Anatomy, showed that at least occasionally, the brain is able to bypass the usual route of nerve fibers it uses for controlling hand and finger movements, using an alternate route to send its signals. Such flexibility in controlling movement has been suspected but not actually shown before.

Investigators at the University of Rochester Medical Center have uncovered a promising drug therapy that offers a ray of hope for children with Batten disease - a rare neurodegenerative disease that strikes seemingly healthy kids, progressively robs them of their abilities to see, reason and move, and ultimately kills them in their young twenties.

The study, highlighted in the January edition of Experimental Neurology, explains how investigators improved the motor skills of feeble mice that model the disease, helping them to better their scores on successive coordination tests. No treatment currently exists for these kids – nothing to halt the disease, or even to slow it down, said one of the study's authors, David Pearce, Ph.D., a nationally renowned Batten disease expert and Biochemistry professor at the University of Rochester. His team has published more than 50 studies on the disease's basic mechanisms.

A brain chemical that makes us sleepy also appears to play a central role in the success of deep brain stimulation to ease symptoms in patients with Parkinson's disease and other brain disorders. The surprising finding is outlined in a paper published online Dec. 23 in Nature Medicine.

The work shows that adenosine, a brain chemical most widely known as the cause of drowsiness, is central to the effect of deep brain stimulation, or DBS. The technique is used to treat people affected by Parkinson's disease and who have severe tremor, and it's also being tested in people who have severe depression or obsessive-compulsive disorder.

Patients typically are equipped with a "brain pacemaker," a small implanted device that delivers carefully choreographed electrical signals to a very precise point in the patient's brain. The procedure disrupts abnormal nerve signals and alleviates symptoms, but doctors have long debated exactly how the procedure works.

"Certainly the electrical effect of the stimulation on neurons is central to the effect of deep brain stimulation," said Maiken Nedergaard, M.D., Ph.D., the neuroscientist and professor in the Department of Neurosurgery who led the research team. "But we also found a very important role for adenosine, which is surprising."

The research by neuroscientists at the URMC was presented at the annual meeting of the Society for Neuroscience in San Diego Nov. 3-7. The work was highlighted as part of a press conference on potential environmental influences on Alzheimer's disease.

The team found that copper damages a molecule known as LRP (low-density lipoprotein receptor-related protein), a molecule that acts like an escort service in the brain, shuttling amyloid-beta out of the brain and into the body. The molecule's role in Alzheimer's was revealed more than a decade ago by another author of the work, Berislav Zlokovic, M.D., Ph.D., professor of Neurosurgery and Neurology and director of the Frank P. Smith Laboratory for Neuroscience and Neurosurgery Research. Zlokovic is widely recognized for demonstrating that blood vessels, blood flow, and the blood-brain barrier are central to the development of Alzheimer's disease.

In the experiment at the University of Rochester Medical Center, worms that are hermaphrodites (with characteristics of both females and males) went for the buttery smell, while the males - the other of the two sexes in these worms - opted for the scent of fresh vegetables. But when researchers tricked a few nerve cells in hermaphrodites into sensing that they were in a male worm, suddenly they too preferred the smell of fresh vegetables.

Geneticist Douglas Portman, Ph.D., and graduate student KyungHwa Lee ultimately hope to understand gender differences in diseases like autism, depression, and attention-deficit disorder. Many more boys than girls are diagnosed with ADD and autism, and many more girls than boys are diagnosed with depression. While proposed explanations abound, few scientists debate the notion that the brains of the sexes are in some ways fundamentally different.

Scientists at the University of Rochester Medical Center have received $1.37 million to continue their work looking at some of the earliest events that occur at the start of Alzheimer's disease - a condition that now generally goes undetected until the death of key brain cells has been underway for decades.

The team led by William Bowers, Ph.D., associate professor of Neurology and a scientist in the Center for Neural Development and Disease, is focusing on the role of inflammation in the evolution of the disease. Just as rheumatoid arthritis can ravage the body's joints because of the inflammation it causes, scientists are realizing that the same thing happens to the brain in patients with Alzheimer's disease. The brain can be under assault for decades as the body attempts to fend off some perceived threat.

Scientists are trying a plumber's approach to rid the brain of the amyloid buildup that plagues Alzheimer’s patients: Simply drain the toxic protein away.

That’s the method outlined in a paper published online August 12^th by Nature Medicine. A team of scientists from the University of Rochester Medical Center, led by neuroscientist Berislav Zlokovic, M.D., Ph.D., show how the body's natural way of ridding the body of the substance is flawed in people with the disease. Then the team demonstrated an experimental method in mice to fix the process, dramatically reducing the levels of the toxic protein in the brain and halting symptoms. The team is now working on developing a version of the protein that could be tested in people with the disease.

This summer the University of Rochester Medical Center boasts winners of two of the most prestigious awards available to young scientists - and the winners are from the same family.

Edward Brown, Ph.D., has been named a Pew Scholar in the Biomedical Sciences, and his spouse Ania Majewska, Ph.D., has received an award from the Alfred P. Sloan Foundation. Brown, one of just 20 scientists in the nation to be recognized by the Pew Charitable Trusts this year, will receive $240,000 toward his research, while Majewska will receive $45,000 to continue her work.

In the June 1^st issue of the Journal of Clinical Investigation, a team of scientists from the University of Rochester Medical Center shows that a key inflammatory regulator, a known villain when it comes to parsing out damage after a stroke and other brain injuries, seems to do the opposite in Alzheimer’s disease, protecting the brain and helping get rid of clumps of material known as plaques that are a hallmark of the disease.

Scientists have found evidence that the cox-2 inhibitor celecoxib, a common pain reliever used to treat arthritis, may offer a new way to reduce the risk of the most common cause of brain damage in babies born prematurely.

The work involves shoring up blood vessels in a part of the brain that in premature infants is extremely fragile and vulnerable to dangerous bleeding, which affects an estimated 12,000 children a year, leaving many permanently affected by cerebral palsy, mental retardation, and seizures.

The laboratory research was done primarily in a laboratory at New York Medical College led by neonatologist Praveen Ballabh, M.D. Ballabh's team worked with Rochester neuroscientists including Maiken Nedergaard, M.D., D.M.Sc., Steven Goldman, M.D., Ph.D., and Nanhong Lou, B.M.

A couple of weeks ago, Gary Paige, M.D., Ph.D., Chair of the Department of Neurobiology & Anatomy, was informed that Ania Majewska, Ph.D., an Assistant Professor who had recently joined the department, had won the Cajal Club Explorer Award. Receiving such a prestigious award is a cause for recognition and celebration. What make's this all the more special, however, is Ania's personal and professional story.

More than a dozen Rochester scientists seeking ways to reverse or lessen the effects of paralysis and other effects of spinal cord injury will begin new projects and continue promising research, thanks to motorists in New York State who push the gas medal a little too far.

Three research projects at the University of Rochester Medical Center are among the programs funded this year through the Spinal Cord Injury Research Program run by the New York State Department of Health. The program, created in 1998, uses fines paid by speeding motorists to fund research into spinal cord injury, whose number-one cause nationwide is motor vehicle accidents. In Rochester this year the grants are going to Roman Giger, Ph.D.; Maiken Nedergaard, M.D., Ph.D.; and Mark Noble, Ph.D.

By blowing gentle puffs of air onto a mouse's whiskers and watching how its brain reacts, scientists are discovering that a long-overlooked signaling system in the brain is crucial to our everyday activity.

The work is the latest in a growing body of evidence that star-shaped brain cells known as astrocytes aren't simply support cells but are stars of the brain in their own right, say researchers at the University of Rochester Medical Center who did the study. The work will be reported in a paper in the June issue of Nature Neuroscience and is now available online.

"Now people have to take astrocytes seriously," said Maiken Nedergaard, M.D., Ph.D., professor in the Department of Neurosurgery and a member of the Center for Aging and Developmental Biology, whose team did the research. In the past few years she has found that the cells, long thought to simply nourish other cells and clean up their wastes, are central to diseases like epilepsy, spinal cord injury, and maybe even Alzheimer's disease.

As part of a five-year, $3.5 million grant from the National Institutes of Health (NIH), researchers will look at whether a breakthrough therapy for Parkinson's disease can also treat the worst cases of obsessive compulsive disorder (OCD). A research team led out of the University of Rochester Medical Center will measure whether Deep Brain Stimulation (DBS) can reduce the rampant anxiety that keeps some OCD patients homebound.

DBS is one of the most promising areas of OCD research because early studies show that it may help many within the approximately 20 percent of OCD patients for whom neither psychological nor drug therapy works, said Suzanne Haber, Ph.D., a professor within the Department of Pharmacology and Physiology at the University of Rochester School of Medicine and Dentistry. Some patients have been able to venture out to work and school for the first time with DBS, said Haber, who is lead investigator for the grant.

New findings that long-overlooked brain cells play an important role in regulating blood flow in the brain call into question one of the basic assumptions underlying today's most sophisticated brain imaging techniques and could open a new frontier when it comes to understanding Alzheimer's disease.

In a paper to appear in the February issue of Nature Neuroscience and now available on-line, scientists at the University of Rochester Medical Center demonstrate that star-shaped brain cells known as astrocytes play a direct role in controlling blood flow in the brain, a crucial process that allows parts of the brain to burst into activity when needed. The finding is intriguing for a disease like Alzheimer's, which has long been considered a disease of brain cells known as neurons, and certainly not astrocytes.

"For many years, astrocytes have been considered mainly as housekeeping cells that help nourish and maintain a healthy environment for neurons. But it's turning out that astrocytes may play a central role in many human diseases," said neuroscientist Maiken Nedergaard, M.D., Ph.D., who has produced a string of publications fingering astrocytes in diseases like epilepsy and spinal cord injury.

Star-shaped brain cells that are often overlooked by doctors and scientists as mere support cells appear to play a key role in the development of epilepsy, researchers say in a study published on-line August 14 in Nature Medicine. It's one of the first times scientists have produced firm evidence implicating the cells, known as astrocytes, in a common human disease.

Scientists found that astrocytes can serve as ground zero in the brain, setting off a harmful cascade of electrical activity in the brain by sending out a brain chemical that triggers other brain cells to fire out of control.

While it's impossible to tell at this early stage what effect the finding will have on treatment, the investigators at the University of Rochester Medical Center are hopeful the results will give doctors and pharmaceutical firms a new target in efforts to treat and prevent the disease.

"This opens up a new vista in efforts to treat epilepsy. It might be possible to treat epilepsy not by depressing or slowing brain function, as many of the current medications do, but by targeting brain cells that have been completely overlooked," says Maiken Nedergaard, M.D., Ph.D., professor in the Department of Neurosurgery and a researcher in the Center for Aging and Developmental Biology, who led the research. "We are hopeful that someday, this will be very beneficial to patients."

ATP, the vital energy source that keeps our body's cells alive, runs amok at the site of a spinal cord injury, pouring into the area around the wound and killing the cells that normally allow us to move, scientists report in the cover story of the August issue of Nature Medicine.

The finding that ATP is a culprit in causing the devastating damage of spinal cord injury is unexpected. Doctors have known that initial trauma to the spinal cord is exacerbated by a cascade of molecular events over the first few hours that permanently worsen the paralysis for patients. But the finding that high levels of ATP kill healthy cells in nearby regions of the spinal cord that were otherwise uninjured is surprising and marks one of the first times that high levels of ATP have been identified as a cause of injury in the body.

While the work opens up a promising new avenue of study, the work is years away from possible application in patients, cautions Maiken Nedergaard, M.D., Ph.D., the researcher who led the study. In addition, the research offers promise mainly to people who have just suffered a spinal cord injury, not for patients whose injury is more than a day old. Just as clot-busting agents can help patients who have had a stroke or heart attack who get to an emergency room within a few hours, so a compound that could stem the damage from ATP might help patients who have had a spinal cord injury and are treated immediately.

A tiny section of the brain that is ravaged by Alzheimer's disease is more important for our ability to orient ourselves than scientists have long thought, helping to explain why people with the disease become lost so easily. The findings by neuroscientists at the University of Rochester Medical Center are reported in the March 29 issue of Science.

Neurologist Charles Duffy, M.D., Ph.D., previously discovered that a small section of brain tissue slightly above and behind the ear - known as the medial superior temporal area (MST) - acts much like a compass, instantly updating your mental image of your body's movements through space. In new research, Duffy and graduate student Michael Froehler show that the MST acts not only as a compass but also as a sort of biological global positioning system, providing a mental map to help us understand exactly where we are in the world and how we got there.

Doctors have added to the evidence that patients with Alzheimer's disease lose their way not simply because their memory is failing but because they are subject to a unique form of brain damage that causes symptoms doctors call "motion blindness." Some of the new data comes from driving tests of a small number of patients, where researchers have linked the condition to the loss of one specific driving skill: the ability to stay in one's lane while driving.

While it's obvious that people with Alzheimer's disease are losing their memory, that's only part of the reason why they become lost, says neurologist Charles Duffy, M.D., Ph.D., who leads the research team at the University of Rochester Medical Center. These patients also lose their ability to perceive their own motion. That's ultimately what puts them at much greater risk than others of becoming lost.