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Science
Friday > Archives
> 1998
> January
> January 2, 1998:
Hour One: Science News/Open Phones:
We're turning this hour over to you to talk about what's on your mind - plus a look at some new findings in biology and from the world of dreams!
So - have you made your New Year's Resolutions yet? Maybe you resolved to find out more about science. Maybe you just resolved to get your voice heard on a great radio program. Stay on top of those resolutions today as Ira opens the phones to hear what's on your mind.
Plus - we'll be taking a look at two new papers published in the journal Science this week. Both deal with ways to visualize information that ordinarily can't be seen by the human eye - gene transcription and brain activity. | What happens in the brain while we dream? A group of researchers at the National Institutes of Health and at the Walter Reed Army Institute of Research have been studying the brain activity of sleeping volunteers. They've learned that the part of the brain responsible for visual activity in dreams is completely separate from the parts of the brain that handle visual input during waking moments. |  | The researchers used a technique called positron emission tomography (PET) to map brain activity while their volunteers slept. They injected a small dose of short-lived radioactive material into the blood of the volunteers, and then used instruments that watched for the positrons given off by the material's decay. Parts of the brain that were more active used more blood - and so had higher concentrations of radioactive material and gave off more positrons. By looking for areas with high positron emissions during REM sleep, the team was able to locate the areas that appear to handle visualization in dreams. Their findings, the researchers say, may help explain why dreams can be so different from real life, from dreamers' heightened emotions to the bizarre nature of the dream world.
Another group of researchers, containing members from Aurora Biosciences, University of the Saarland, and the University of California at San Diego has improved on methods for seeing another elusive vision - the process of gene transcription in cells. The team reports that they have developed a way to watch in real time as single cells transcribe their DNA.
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First, they inserted a gene that codes for the production of a bacterial enzyme, beta lactamase, into the DNA of the cells that they wished to monitor. Then the team placed a color-changing, cell-permeable substrate into the cells. As the cell transcribed its genome, it produced the enzyme, causing the substrate to change color from blue to green.
While other such transcription tests, using enzymes called "reporters," already exist, the new method can be used on single cells and in cells without permeable membranes, thus making the technique more useful to researchers. The technique also works without killing the cells, a problem with some earlier methods. | 
Live human T-lymphocytes expressing a new
reporter gene stain blue, while nonexpressing
cells glow green. (click for larger version)
Copyright Gregor Zlokarnik (Aurora Biosciences Corp.)
and Roger Tsien (Howard Hughes Medical Institute and
University of California, San Diego). |
Guests:
Allen Braun
Acting Chief, Language Section
National Institute on Deafness and Other Communication Disorders
National Institutes of Health
Bethesda, MD
Tom Balkin
Walter Reed Army Institute of Research
Washington, DC
Roger Tsien
Professor, Pharmacology and Chemistry and Biochemistry
Investigator, Howard Hughes Medical Institute
University of California at San Diego
San Diego, CA
Books/Articles Discussed:
Related Links:
Behavioral
Biology at Walter Reed
PET Scan background
PET Scans of hearing
vs seeing
Aurora Biosciences
Pharmacology Department, UCSD
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