A. A New Treatment
For Hip Osteonecrosis
Narrator: This is Science Today. A new technique
called osteoregeneration has been developed at UCLA
to treat hip osteonecrosis. Dr. Jay Lieberman, who
developed osteoregeneration, says osteonecrosis
- which affects about 20 thousand people each year
- literally means Abone death.
Lieberman: It's actually death of the bone
in the femoral head which makes a part of the hip
joint. We're not sure how the bone dies in certain
conditions but it is associated with certain risk
factors - trauma, fracture of the femoral neck or
dislocation of the hip, the use of steroids like
prednisone and then alcohol abuse.
Narrator: Lieberman uses an existing technique
that involves drilling a hole to remove dead bone
but then modifies it by inserting a capsule filled
with bio-morphogenetic protein, or BMP. This protein,
discovered in 1965 by UCLA's Dr. Marshall Urist,
stimulates cells to generate new bone.
Lieberman: We believe that the technique
is very promising because we believe it's a more
biological solution than we've had in the past of
just drilling the hole.
Narrator: For Science Today, I'm Larissa
Branin.
B. Getting Rid of Selenium Contamination
- Naturally
Narrator: This is Science Today. A safe
and effective way to detoxify selenium-contaminated
soil, water and sediment has been developed by a
University of California, Riverside laboratory.
William T. Frankenberger, Jr., a professor of soil
microbiology who runs the lab, says the process
utilizes bioremediation - in which natural microorganisms,
like bacteria or fungi, break down the contaminants.
Frankenberger, Jr.: We're trying to promote
their activity and growth to take up the selenium
and convert it into a gas so that we can dissipate
the selenium from a very concentrated area and basically
disperse it at a level which would be non-toxic.
Narrator: The microorganisms were stimulated
by pectin, a common ingredient found in plants.
In this case orange peels, which are loaded with
pectin, were used.
Frankenberger, Jr.: The fungi consumed the
orange peel and in doing so, they grow, proliferate
and they take up more selenium in the soil and water.
And in doing so, more selenium gas comes off.
Narrator: For Science Today, I'm Larissa
Branin.
C. Marijuana & Crack Cocaine Linked
To Risk of Lung Cancer
Narrator: This is Science Today. For the
first time, researchers have found that tobacco
is not the only smoked substance that can lead to
lung cancer. Dr. Sanford Barsky, a professor of
pathology at UCLA, found heavy smokers of marijuana
or crack cocaine display the same molecular, pre-cancerous
changes as those who smoke tobacco.
Barksy: Before this study, there was really
no evidence that marijuana or crack cocaine did
these things. But you have to remember that these
are heavy, habitual smokers of these drugs. It doesn't
follow that someone who occasionally smokes marijuana
or crack cocaine will have these findings.
Narrator: But the study did find that habitual
smokers of more than one substance had greater risk
of lung cancer than those smoking just tobacco alone.
Barsky: We didn't do this study to fuel
the controversy concerning the benefits or detriments
of marijuana or crack cocaine. It was motivated
because there's an increasing use of marijuana and
crack cocaine and we wanted to see the effects of
these substances on the lung. And also because we
now understand some of the molecular steps that
lead to lung cancer.
Narrator: For Science Today, I'm Larissa
Branin.
D. Getting The Most Out Of Our
Muscle
Narrator: This is Science Today. Muscle
atrophy refers to the shrinkage of muscle fiber
from lack of forceful exertion. Dr. Kenneth Baldwin
of the University of California, Irvine worked with
NASA to come up with an exercise routine to prevent
this from occurring in astronauts traveling through
space. Since muscle atrophy parallels the aging
process, Baldwin says their findings can also be
applied to the general public - especially those
over forty.
Baldwin: What we've learned over the years
is that we should be using more activity regimens
that are called high force, low frequency - as in
lifting against a very heavy object.
Narrator: But how does one know if they're
putting enough stress on their muscles?
Baldwin: One simple way is that if you are
lifting weights and you can basically generate about
ten contractions during one session and by the tenth
contraction you can hardly move that object, you
are pretty sure that that individual muscle group
is being adequately stressed.
Narrator: For Science Today, I'm Larissa
Branin.
E. Cracking An Age-Old Problem
Narrator: This is Science Today. On any
given sidewalk, you're more than likely to encounter
cracks in the pavement. These cracks develop when
fluids in the cement mix with silica in the concrete,
forming what's called an alkali- silica gel. Researcher
Bill Carey of the Los Alamos National Laboratory
says in time, this gel expands and causes cracks.
Carey: What we wanted to do was to study
this to learn the mechanisms and to propose solutions
to prevent this from happening either by changing
certain chemical aspects of cement in such a way
that gel would maybe not form or if it did form,
not be a swelling gel and cause cracks.
Narrator: The first step towards prevention
is detection, so Carey helped develop a quick, color-coded
stain test, which is safer than the standard test
that uses uranyl acetate.
Carey: Urunayl acetate is a heavy metal,
mildly radioactive and presents real disposal problems,
in addition it was sort of hard to work with because
you put the urunayl acetate solution on and then
you look at the surface under ultraviolet light.
Narrator: For Science Today, I'm Larissa
Branin.
