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Medical Decade as seen on The Frontiers Decade

q Is it harder to control the robot hands during remote-control surgery than to do the real thing? And how do you make the robotic hands?

A It is actually easier, because the computer in the surgical workstation can be used to magnify the motion of the robot hands, to make the motion more precise. The robotic hands are mechanical, with a series of cables and wheels to control it. There isn't any "hand" as you know it, but rather than the "hand" there is a "joint" where the different instruments can be installed and exchanged.
Richard M. Satava, MD
21st Century Medicine, April 1996

q Do you think it will ever be possible to replace a body part as delicate and as intricate as a brain or an eye.

A Maybe. Ten years ago, one would be skeptical about reconstructing in laboratory even a small patch of cardiac muscle, or a piece of cartilage or bone. The organs you mention are among the most complicated ones. We should revisit this subject in 5 or 10 years and see how much progress has been made. I am among those who think that there is a long way to the time we can make any of the human organs.
Gordana Vunjak Novakovic
Never Say Die, January 2000

q What are the prospects for the future simulation of a more natural walk for paralyzed individuals, and for new breakthroughs in the size and convenience of the hardware involved?

A The prospects for a more natural walk are excellent. The Department of Veterans Affairs is currently funding two projects with that goal. One provides feedback so that the computer knows what it has done and can make corrections. The other creates a more natural appearing walking system that will allow transfer of the technology to other medical centers.
Byron Marsolais, MD
21st Century Medicine, April 1996

q How are people who are infected with the malaria parasite cured? What medications are used in the treatment?

A They are cured by using drugs that eliminate the parasite from the body. There are many of these, but the situation has been compromised by the development of multiple drug resistance. This is especially the case in S.E. Asia where virtually none of the prophylactic (preventative) drugs work. Drugs such as chloroquine were cheap, had few side effects and were effective in both the treatment and prevention of malaria. In 1978 chloroquine resistance arrived in Africa and now it covers the whole continent. Unfortunately many of the alternatives are more expensive and have greater side-effects. Thus for the traveller from the West who can afford the right drugs it is not really a major problem, but for the rural poor of Africa it is. Some medications used are: Fansidar-sulphadoxine/pyremtehamine; Hafan-Halofantrine; Lariam-Mefloquine; Quinine. The last is the oldest and still the most widely effective. It was derived from the choncona tree in South America and was discovered by Jesuit monks. Its discovery was a powerful tool in their hands as it was kept secret and enabled them to effectively colonise malaria areas.
David LeSueur
Science Safari, November 1996

q Have any western pharmaceutical companies been working with the traditional South African healers to "discover" new drugs?

A Great interest and research is currently being done by both American and South African companies to discover new drugs. The potential to make a new discovery is fantastic, as our plant species diversity is very large. A lot of the work done is secretive, due to the high research costs and potential earnings. The work is further complicated by the fact that remedies are seldom single plants, but a concoction of a number of plants. The chemical compounds formed are complex and time consuming to break down.
Danny Lenferna
Science Safari, November 1996

q The people we saw on the show practicing Therapeutic Touch seem to really believe in what they're doing and can describe physical sensations pretty clearly. Do you really think that these people might have certain "powers," or are they all just faking it?

A I think that they were probably sincere about being able to feel something, but my experiment did not show evidence that the "human energy field" exists. When I was doing my test, I got the feeling that they were having a hard time feeling anything when they couldn't see my hand and were just guessing. To really know if they can feel something there, I need other people to repeat my experiment. If the results of their test come out the same, we will know that there is no such thing as a human energy field and these people are imagining or pretending. In Pennsylvania, there is a girl, 9-years-old, who is going to replicate my test. I do not believe that these people are feeling something. After you pretend for a while, you starting believing there is something there. Nurses are told by their instructors that there is good research (not so) for Therapeutic Touch, and they want to help their patients, so they want to believe TT is real. Dolores Krieger, the founder of TT, was in Denver recently, and I asked her for ten minutes of her time to take my test. She was a big "scaredy-nurse" and sent me a message that she didn't have time.
Emily Rosa
Beyond Science?, November 1997

q Is there any evidence that eating a calorie-restricted, highly nutritious diet actually reverses aging to some extent, or does it only retard the aging process from the time that you begin the diet? And is there any evidence this diet can reverse diseases, such as heart disease or diabetes?

A As far as reversing aging, the answser is both yes and no. Blood pressure and blood sugar, for example, tend to increase with age, and the diet will return those and many other values to those of a younger age. Same for the immune response. So in a limited sense, that's "reversal" of aging. But wrinkles, graying of hair, and other parameters will not be reversed, only slowed down in their advance. So I am very hesitant to claim anything like "reversal." While there is over 50 years of animal research, calorie restriction has not as yet been specifically tested for treatment of heart disease and diabetes in humans, but judging by what it does for the "risk factors" of those diseases, it should should strong therapeutic effects. In my view, nobody should be going for bypass cardiac surgery who has not FIRST been offered nutritional treatment of their condition. Then, those who can't or won't do it -- they go to the operating room. The others improve without surgery.
Roy Walford, MD
Never Say Die, January 2000

q Alan Alda asked what possible reason an organism would have to cause its own demise, and you said, essentially, nobody knows. I always thought that it would be beneficial for the old generation to get out of the way for the new one. Otherwise, the old guys would be around competing with the new guys, who hopefully have the better genes. Is this a completely wacko idea?

A I like your idea. Here is my favorite idea: In the presence of food and low population density, worms reproduce rapidly, producing 300 progeny in the first three days of adulthood. That's an amazing rate of compounding. (Imagine your 401k compounding at a rate of 300% every three days. Soon you would own everything (very soon).) For the worm, this is a strategy that converts whatever the worms are eating into more worms very rapidly. Now, I didn't say this on the TV show, but we know that the long-lived mutants are resistant to damage caused by oxygen (free radicals, which produce oxidative damage) and other environmental stresses. We also know that at least some genes, like a gene encoding the protein superoxide dismutatase (which prevents free radical damage) are expressed at very high levels in these long-lived worms. It seems to me that it would be energetically more expensive to produce such a "superworm". Therefore, a population that did this (used some of its food to make the worms more resilient than then need to be just to produce their 300 progeny) might lose out to one a population that converted every drop of food into more worms.
Cynthia Kenyon
Never Say Die, January 2000

q In your study tracking the physical and mental activities of older people, have found that any specific activities stand out as being particularly beneficial for keeping the mind and memory sharp?

A The mental activities that seem beneficial for maintenance of mental ability are things like: reading books, doing crossword puzzles, going to lectures and concerts. These activities make sense, if you think about it, they are most likely to be mentally challenging and present new information. Watching a lot of TV actually seems to put a person at risk for decline -- unless, of course, it is Scientific American Frontiers.
Marilyn Albert
Never Say Die, January 2000


Scientific American Frontiers
Fall 1990 to Spring 2000
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