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A.
Mild Concussions in Children May Not Be So Mild
Narrator:
This is Science Today. A UCLA study suggests mild
concussions in children may impair the ability of
the child's brain to develop to its full potential.
Dr. David Hovda, director of the UCLA Brain Injury
Research Center, worked with young rats and found
while they recovered well from mild concussions,
they could not enhance their learning capacity,
which is known as plasticity.
Hovda:
And we think that this is because that following
concussive brain injury, the biomechanics of the
injury actually produce a series of neurochemical
and metabolic events in the brain that compromises
the brain's capacity to enhance its plasticity due
to a unique exposure to an enriched environment.
Narrator:
Hovda says his research suggests that potentially
these young brains may need to be treated a little
differently than the adult's central nervous system
when it's injured.
Hovda:
Because the consequences of the reduction in capacity
for plasticity may be much greater.
Narrator:
For Science Today, I'm Larissa Branin.
B.
A Study Finds We're a Sleep Deprived Nation
Narrator:
This is Science Today. According to the National Sleep
Foundation, almost two-thirds of Americans are sleep
deprived. And yet, Dr. Chris Gillin, of the University
of California, San Diego conducted studies suggesting
the brain may have an adaptive resource to make up
for sleep deprivation. Still, Gillin says a lack of
sleep should not be taken lightly.
Gillin: Performance drops when
people are sleep deprived. They're at increased risk
of automobile accidents and it certainly has been
implicated in some very serious disasters. For example,
the Three Mile Island nuclear disaster occurred in
the middle of the night and it was thought that sleep
deprived employees made some human errors that resulted
in that.
Narrator: Gillin and his colleagues
found that the sleepier a person was, the greater
the activation in a part of the brain that controls
judgment and working memory.
Gillin:
This was
unexpected to us, but it does suggest that the brain
does have compensatory mechanisms and it's not just
a simple sleep deprivation effect. It's probably really
related to the task that the subject is performing
and to a number of other variables, such as how well
they're performing or how sleepy they are.
Narrator:
For
Science Today, I'm Larissa Branin.
C.
StarLink: The Controversial Biotech Corn Variety
Narrator:
This is Science Today. Nearly eighty U.S. seed companies
have found corn seed contaminated with traces of a
biotech variety known as StarLink, which had been
associated with an earlier nationwide recall of taco
shells. Norman Ellstrand of the University of California,
Riverside, is an expert in the field of trangenics.
Ellstrand:
Now, how did the StarLink gene get into the traditionally
bred corn? It's possible that the seeds were mixed,
it's possible that there was contamination in the
equipment that was used to evaluate this, but it's
also possible that hybridization between StarLink
that was being grown by thousands of acres occurred
with traditionally improved crops.
Narrator:
The FDA approved of StarLink only for animal consumption
because there's question about its potential to cause
allergies in humans. But Ellstrand says there's no
reason for great alarm.
Ellstrand:
The StarLink protein is probably not one that's
going to cause a lot of problems, but it sets a bad
precedent for our ability to keep track of genes.
Narrator:
For Science Today, I'm Larissa Branin.
D.
Some Fascinating Facts About Spiders
Narrator:
This is Science Today. An single spider can spin more
than one kind of silk for all different purposes.
There's one silk that just covers eggs and another
that makes the typical wagon wheel-type web to catch
prey. Even within that one wagon wheel web, there
are different kinds of silks that make up the structure.
Cheryl Hayashi, an associate professor of biology
at the University of California, Riverside, studies
spider silk proteins.
Hayashi:
One of the other really cool things about spiders
and their ability to make silk is that as that spider
is reeling down - it's not as if inside the spider
it has a spool of spider silk in there. When you see
it dropping down that way, what you're seeing is,
what's happening in real time is liquid protein is
being turned into a thread at the rate you're seeing
that spider drop.
Narrator:
Hayashi says there's great interest in making synthetic
spider silks to produce eco-friendly superfibers.
Hayashi:
Think of something like nylon. That requires petroleum-based
chemicals and some pretty harsh industrial processes
that turn the soup into a nylon thread…and spiders
are doing it in your house. They're probably doing
it right now!
Narrator:
For Science Today, I'm Larissa Branin.
E.
The Advantages of Colon Cancer Screening
Narrator:
This is Science Today. Each year, about 55 thousand
people will die from colon cancer, making it the second-highest
cause of death from cancer in the nation. And yet,
if detected early, colon cancer can usually be treated
successfully. But Dr. Charles Theuer, of the University
of California, Irvine, says there's a certain stigma
associated with getting screened for colon cancer.
Theuer:
Educated people that know all the pros and cons,
know it's very safe and it can save your life, still
say, "Oh - I just don't want to do it."
So we've got to somehow get the stigma to the other
side - we've got to make it a stigma not to have it
done and right now we're not at that point.
Narrator:
Theuer says one of the big advantages of colon cancer
screening is the fact that polyps, which are sometimes
a precursor to cancer, can also be removed during
the procedure.
Theuer:
Which
is a real advantage in colon cancer screening that
you don't see for instance in breast cancer screening.
There, we're looking for cancers - early stage. In
colon cancer, we're looking for early stage cancers,
but what we really can do is get rid of the polyps
that become cancers before there's any chance of the
patient having a problem.
Narrator:
For
Science Today, I'm Larissa Branin.
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