Research Notes

Alzheimer's: Type 3 Diabetes?

Is Alzheimer's disease a new form of diabetes? Medical School professors Suzanne de la Monte and Jack Wands believe it could be. Their research, published in the March issue of the Journal of Alzheimer's Disease, shows that insulin is not only produced in the pancreas, but also in the brain. They also show that reduced levels of insulin and its related proteins contribute to the progression of Alzheimer's, a degenerative brain disorder affecting 4.5 million Americans.

The provocative findings received international attention, including coverage on more than sixty-five U.S. TV stations and a front-page story in the Atlanta Journal-Constitution.

Science and Self-Censorship

Government bans and political pressure - think embryonic stem cell research and human cloning - constrain science. But scientists also censor themselves.

In a February paper in Science, Assistant Instructor in Dermatology Clifford Perlis and colleagues revealed results of forty-one interviews with geneticists, biologists, psychiatrists, and other researchers. The team found that fear of controversy over hot topics such as race and intelligence as well as fear of protests from animal rights groups are even more powerful forces than politics in suppressing science. Scientists reported shying away from exploring certain topics, experimenting with animals or publishing controversial results.

The Associated Press covered the research.

Intermetallic Mystery - Solved

Intermetallics could be the key to faster jets, more efficient steam turbines, and better car engine valves. But these heat-resistant, lightweight compounds have stumped scientists for decades. Why do so many break so easily? Professor of Engineering Sharvan Kumar cracked the code with colleagues from the Oak Ridge National Laboratory and UES Inc. The team used the world's most powerful electron microscope to see, for the first time, atomic details that may provide the answer for the most common class of intermetallics. Their results - which could open the door for new materials for commercial use - were published in Science in February.

Inner Workings of Exotic Eye Cells

Three years ago, neuroscientist David Berson made an astonishing announcement: Rods and cones aren't the only light-sensitive cells in the eye. In a January report in Nature, Berson and other Brown colleagues explained how these mysterious spidery cells, called intrinsically photosensitive retinal ganglion cells or ipRGCs, harness light energy.

A protein called melanopsin, the Brown team found, absorbs light and triggers a biochemical cascade that allows the cells to signal the brain about brightness. Through these signals, the ipRGCs set the body's master circadian clock. This circadian rhythm controls alertness, sleep, hormone production, body temperature and organ function.

Drug Target Found for Breast, Prostate Cancer

Medical School and Rhode Island Hospital researchers have found that STAT3, a cause of breast and prostate cancers, switches on in two ways. The team of cell biologists, led by Eugene Chin, discovered a new chemical modification that activates STAT3, a so-called signaling protein that, when unexpectedly and continuously activated, causes cancer cells to develop and move through the body. Drug makers can use the findings to try to inhibit this protein more effectively. The target is important: Breast and prostate cancer are the most commonly diagnosed cancers in the United States. The team published the results in Science in January.

Sea Skate Experiment Sheds Light on Human Cell Transport

An experiment using the red blood cells of skates - the flat, boneless fish - has netted a critical finding about how human cells work. Leon Goldstein, a professor of medical science, and University of Chicago researcher Mark Musch discovered how cellular "gates" are activated to disgorge excess water. The pair believes the molecular mechanisms that trigger this "release valve" are common to many cells and may provide clues for diabetes and cancer treatment.

These findings are published in the April issue of the American Journal of Physiology: Regulatory,Integrative and Comparative Physiology.

New applications for MEG technology

John Donoghue isn't the only Brown scientist at work on a mind-to-movement device. Jerome Sanes, a professor of neuroscience, is also trying to tap brain signals that control movement and use those signals to power prosthetics for amputees.

Sanes was recently awarded a $340,000 subcontract from Canadian medical device manufacturer VSM MedTech to investigate the possibility of whether magnetoencephalography (MEG) technology can provide brain signals clear enough to control devices such as artificial limbs.

How MEG works: Brain impulses generate magnetic fields, which are picked up by VSM MedTech's machine, which uses 275 superconducting sensors arrayed around the skull. Computer algorithms interpret the resulting signals, creating functional brain maps of movement.

Surgeons use MEG technology to locate the source of abnormal brain activity in people with epilepsy. Sanes will apply it in a new way. Working with Applied Math Professor Elie Bienenstock and neuroscience postdoc Richard Archibald, Sanes will try to capture and decode human MEG signals in real time. If the team succeeds, the signals might be used to move a prosthetic limb.

Although Donoghue's BrainGate system picks up signals directly from the brain through an implant, the system Sanes will work on wouldn't require surgery because it uses external sensors.

Compiled by Wendy Y. Lawton