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04/17/2003
Reflections on a Milestone
If I’ve counted correctly, this is the 200th Bortrum column.
Surely, such a milestone warrants some degree of personal
satisfaction and reflection. I’ve often been asked how I come up
with topics for these columns. OK, more accurately, my wife
asked me last week, “What are you going to write about this
week?” I replied that I often don’t know the answer until I sit
down and start typing, as is the case with this column. If science
is a search for the truth, it’s also true that, when it comes to the
truly big questions, the quest for absolute answers is seldom
achieved. Some of the themes of past columns reflect this
continuing search for ultimate answers to big questions.
For example, we discussed possible answers to the left-
handedness of Nature in a recent column (2/7/2003). But it
remains to be shown whether this left-handedness arose from
outer space or from here on Earth. And, to bring the subject up
to date, why did it take all these years for a lefthander to win The
Masters? Even more perplexing, why was it Weir and not
Mickelson? And why did Tiger listen to his caddy and end up
having to hit a left-handed shot out of the woods? These
relatively simple questions illustrate the enormity of trying to
find absolute truth.
My first column (5/12/1999) was titled “NO, NO, NO”. It dealt
with Viagra and the role of nitric oxide, NO, in the erective
process. At that time, it was clear that NO is a very important
molecule in our bodies and not just in the area of enhancing male
sexual performance. NO is involved in the dilation of blood
vessels and in the regulation of blood flow to tissues. NO also
regulates the uptake and release of oxygen from hemoglobin,
thus controlling the supply of oxygen to mitochondria.
That first column was based on an article titled “Say Yes to NO”.
Naturally, I was curious when I saw a “perspective” by Guy
Brown in the February 7, 2003 issue of Science titled “NO Says
Yes to Mitochondria”. Mitochondria are the little compartments
in our body’s cells that take in food and oxygen and spit out a
chemical known as ATP. ATP furnishes the energy to drive our
bodily processes. In other words, mitochondria are the tiny
powerhouses that keep us alive and kicking.
The perspective was prompted by an article in the same issue of
Science by Enzo Nisoli and ten Italian colleagues. The article’s
title was more complicated but the bottom line is simple - NO
has now been found to stimulate the synthesis of new
mitochondria. This finding may not thrill you but hang in there,
especially if you’re like an estimated 65 percent of us Americans,
overweight or outright obese. Nisoli is associated with the
Center for Study and Research on Obesity at Luigi Sacco
Hospital in Milan. What’s the connection? If you’re talking
mitochondria, you’re talking about energy production and
balance. If you expend more energy than you consume, you lose
weight and vice versa. It’s the “vice versa” that’s the big
problem. If scientists can figure out how to regulate and channel
NO to the proper locations in our bodies, perhaps by means of a
new drug, we might be able to make progress against the obesity
epidemic. With obesity-related diseases taking an estimated
300,000 lives a year, I have the feeling I’ll be discussing more
about NO in future columns.
In only my third column (5/25/1999), I had the temerity to write
about dark matter, a subject totally beyond my comprehension.
However, nobody else seems to know what dark matter is and I
was emboldened to write in later columns about such things as
black holes and, weirdest of all, a new thing called dark energy.
Even Einstein, whose cosmological constant was equivalent to
dark energy, couldn’t accept the concept and discarded it as his
greatest mistake. But now it’s needed to explain why our
universe is expanding at an accelerating rate. To top it off, it was
just a few weeks ago (2/27/2003) that I wrote about NASA’s
WMAP mission, which showed that 73 percent of our universe is
dark energy. That mission also nailed down the age of the
universe.
Since the WMAP results were released, I’ve seen an article by
some British workers who point out that the WMAP mission
hasn’t solved everything. For example, it hasn’t pinned down
whether dark energy is so-called vacuum energy or something
theorists call “quintessence”. There’s no way I can deal with
either of these concepts but rest assured that, if I live so long, I’ll
be back with a column on them.
In my sixth column (6/15/1999), I discussed how a reaction to
my smallpox shot, required to enter school in those days,
affected the entire course of my life. Today, a controversy rages
over the program to vaccinate health care and other emergency
responders against smallpox. Until recently, it had been my
assumption that my immunity was good for life but that seems
not to be the case. With vaccination a public issue, the race is on
to come up with vaccines for AIDS, West Nile virus, Lyme
disease and now SARS. Let’s hope I can write a column about a
success in some of these endeavors.
Although our editor, Brian Trumbore, is gung ho on sending a
manned mission to Mars, I’ve discussed (May 29, 2001) the
physiological and psychological challenges presented in such a
journey. In other columns, I’ve discussed other planets or
heavenly bodies, even Hedy Lamarr and her contribution to
secure communications. But Mars has always been the planet of
greatest interest as a possible habitat for extraterrestrial life. This
past December, in a Science online paper, Philip Christensen of
Arizona State University and Timothy Titus and Hugh Kieffer of
the U.S. Geological Survey reported that they had found a patch
of ice in the region of Mars’ South Pole. They came to this
conclusion from a study of Mars Odyssey and Viking spacecrafts
and from infrared measurements of the heat absorption and
radiation in daylight and at night.
The patch is about a half-mile wide and one hypothesis is that in
the Martian summer a covering of solid carbon dioxide, dry ice,
evaporates and exposes the water ice. There’s a chance that the
water ice patch is much more extensive than the exposed section,
hidden by the dry ice covering. Needless to say, this finding has
spurred serious thought about a future polar lander mission to dig
into this water ice.
Speaking of carbon dioxide, it can be deadly, as we discussed in
a column on February 20, 2001. Roughly 1800 people died from
exposure to carbon dioxide gas in incidents in Africa in which
carbon dioxide gas was emitted in huge bursts from “killer”
lakes. In these lakes, Lake Nyos and Lake Monoun,
underground springs containing carbon dioxide of volcanic
origin feed the lakes, building up water rich in carbon dioxide on
the bottoms of the lakes. When some sort of disturbance hits the
lake, it’s like opening a bottle of soda – the carbon dioxide is
spewed out in large amounts. Carbon dioxide is normally a
benign gas; we’re breathing gobs of it out even as we speak.
However, get too much in the air and we suffocate.
Two years ago, an attempt was made to alleviate the danger
posed by one of these lakes, Lake Nyos, by putting a pipe into
the lake in an attempt to vent the carbon dioxide from the bottom
of the lake. Now the results are in (article by Kevin Krajick,
Science, February 7 2003). While the level of carbon dioxide
has dropped about 6 percent, the venting is barely keeping up
with the introduction of new carbon dioxide from the
underground springs feeding the lake. At this rate, it will be
several decades before that lake is safe. In January of this year,
an effort began to put a number of pipes into Lake Monoun. If
enough of the anticipated money to fund the project materializes,
this lake should be safe in just a couple of years.
We’ve considered a number of interesting forms of animal life,
as well as experiments with animals that might benefit us
humans. Typically, these experiments have been done with
animals such as rats, mice or primates. With Christopher
Reeve’s spinal injury and his remarkable progress, experiments
indicating the possibility of nerve regeneration or reconnection in
lab animals are promising. In the December 13 2002 issue of
Science, Kenneth Poss and colleagues at Harvard Medical
School reported a shocking regenerative capacity in a fish.
Apparently, it has been known that zebrafish have the ability to
regenerate spinal cords, fins and retinas.
That’s pretty impressive but the Harvard researchers have carried
it even further. When we humans have a heart attack, scar tissue
forms over the damaged portion of the heart. The Harvard
researchers surgically removed parts of the hearts of zebrafish
and waited. The heart muscle was regenerated! Could the same
thing be achieved in humans? Stay tuned.
Allen F. Bortrum
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