Medicine on Brink of Breathtaking Feats in Technology
It looks like an ordinary microchip, but it may have a life of its own. Someday, it could end up inside somebody’s brain.
Scientists from the National Institute of Mental Health are growing animal tissue on a silicon chip in the hope that the two eventually will connect and begin to interact. Sometime, probably well into the next century, microchips may be implanted in human brains, where they will link up with undamaged nerve cells and take over functions destroyed by injury or disease.
Other medical scientists are wrestling with an age-old question: Can human life be significantly prolonged?
Aging Process
Researchers on aging say that if cancer and heart ailments magically disappeared, the average American life span would increase by only about seven years. These scientists are trying to retard the aging process itself, extending the years of robust health toward 100. One theory is that aging is caused by the buildup of metabolism’s toxic byproducts and could be slowed by boosting the body’s protective enzymes.
A formula for extended youth may never be found. But by 2000, many of the human body’s remaining secrets will have been unlocked. New discoveries are occurring almost daily, especially in molecular biology--the study of the body’s functions at the basic genetic level. The advances will make today’s medicine look primitive.
Technology, some of it extremely costly to operate, will produce unprecedented tools for diagnosing and treating disease. New body scanners, especially the magnetic resonance imager, will produce photograph-like pictures that reveal far more than today’s CAT scanners, without using radiation.
Tiny pumps implanted in the body will take over for ailing organs, shooting out insulin for a malfunctioning pancreas, for example. Lasers will take over most work now done by scalpels, perhaps even making coronary bypass surgery obsolete.
Role of Robots
Robots will work alongside some surgeons. “For certain functions, robots will be more accurate than people, and they’ll take care of repetitive tasks too, such as suction and retraction,” says Dr. Donlin Long, chairman of neurosurgery at the Johns Hopkins University Medical School.
“Teleradiology” will convert future accident victims’ X-rays to digits and send them by telephone to specialists for instant analysis. Doctors will turn to computer terminals, not musty reference books, for guidance on symptoms, treatments and prescriptions. One futurist predicts that, within 50 years, many doctors will be replaced by technicians operating well-programmed computers.
Meanwhile, health specialists say, more physicians will cease being repairmen. By 2000, Americans may spend as much time and money on prevention of illness as on treatment and look to changes in life style, not technology, for their well-being.
“We have it within ourselves to control our cardiac destiny,” says Dr. Robert I. Levy of Columbia University. He believes that education about smoking and diet, especially cholesterol, will help bring heart disease down as the nation’s No. 1 cause of death within 15 to 20 years.
New Wave of Vaccines
A new generation of drugs will aim at preventing and curing disease rather than treating symptoms. Made more by biologists and computer scientists than chemists, these drugs will be cloned from the body’s own genes, hormones and enzymes and will mimic nature to cure ills. The next century also will see a new wave of vaccines to prevent such illnesses as chicken pox, malaria and hepatitis--and even tooth decay.
Viruses, which cause a range of illnesses, including the common cold, herpes and AIDS, will remain a challenge. Although researchers recently described for the first time the complex architecture of a human cold virus, they are a long way from developing a vaccine for virus-related diseases.
Areas of medical research with great significance for the future include:
- The Brain--”As heart disease and cancer become more treatable, the major American health problem over the next 50 years will be degenerative diseases of the brain,” says Dr. Richard Jed Wyatt, chief of neuropsychiatry at the National Institute of Mental Health. Some experts expect cases of Alzheimer’s disease, a type of dementia, to triple in the next 75 years as the population ages.
But an explosion of research on the brain, one of the last frontiers of medical science, will offer eventual cures for some of today’s most feared disorders. For example, a recent discovery that the brain has at least 50 and perhaps hundreds of neurotransmitters--chemicals that direct much of its function--probably will lead to new treatments or cures for Parkinson’s disease, epilepsy, schizophrenia, chronic pain and even Alzheimer’s.
‘Demystifying the Brain’
The workings of the mind, once thought to be intangible and invisible, will be traced with new scanners. “We’re in the process of demystifying the brain. By the year 2000, we may know exactly what is happening, say, in my brain while I’m talking to you,” says Dr. Katherine Bick, deputy director of the National Institute of Neurological and Communicative Disorders and Stroke.
Future drugs will literally refresh our memories. “Using certain drugs, we now can make animals remember better, and I believe that, before long, we’ll help humans with memory problems,” forecasts Dr. James L. McGaugh, director of the Center for the Neurobiology of Learning at the University of California, Irvine. Several U.S. drug manufacturers already are researching these “cognitive enhancers.”
One of the most ambitious areas of brain research is an effort to make a damaged brain “whole” through special surgery. Wyatt has found that rats suffering symptoms of Parkinson’s disease--a deficiency of a neurotransmitter that afflicts 500,000 Americans--can recover if affected brain tissue is surgically replaced by new cells. If the process works in rhesus monkeys, Wyatt believes, it eventually should work in humans. One scientist predicts that such transplants will be routine for some brain diseases by 2000, if ethical questions are resolved.
- Genetics--Gene by gene, scientists are mapping the human body. The number of identified genes is roughly doubling every two years, and, although the rates will slow, many of the significant ones will have been located by the turn of the century. Last year, for example, scientists found the gene that corresponds to the fatal Huntington’s disease.
About 3,500 illnesses have been linked to genetic defects, including many forms of mental retardation, and future scientists may be able to treat them. Beyond that, genetic mapping will help explain a broad range of biological functions, such as the process that causes chromosomes to rearrange themselves and trigger cancer, says one of the mappers, Dr. Frank Ruddle of Yale University.
Although ethical questions loom, the new knowledge should yield advances for future health care, among them genetic vaccines and drugs, prenatal screening and early warnings of predisposition to certain adult disease, even those caused by a combination of hereditary traits.
“Now, for instance, we have to tell the whole population to cut down on fats,” says Dr. Arno G. Motulsky, director of the Center for Inherited Diseases at the University of Washington, Seattle. “When we can detect genetic predisposition to heart disease, we’ll be able to target those people at risk, and the rest may be able to eat as much fat as they want.”
Genetic Drugs
Many future prescription drugs will be genetically based, creations of a “gene machine.” Now able to make a small gene in less than a day, the device can recreate genes already in existence or synthesize genes unknown to nature, says Dr. Leroy E. Hood of the California Institute of Technology in Pasadena.
If current animal studies succeed, 21st-Century doctors likely will practice “gene therapy,” inserting normal genes to correct mistakes in patients’ genetic makeup. In the next year or two, the first trial of human gene therapy will be conducted on ADA deficiency, a life-threatening enzyme shortage.
“If gene therapy works with ADA, any hereditary disease could theoretically be treated with gene therapy,” says Dr. W. French Anderson, chief of the National Heart, Lung and Blood Institute’s molecular hematology laboratory.
Eventually, the treatment could be simple: “A visiting nurse could cure sickle-cell anemia in a population with injections into the bloodstream,” Anderson says. Like tuberculosis and polio, most genetic disorders could be virtually banished.
Ethical concerns envelop gene therapy, especially the question of using it to change future offspring and “enhancement gene engineering”--insertion of a gene to improve a trait such as intelligence. But such tampering is unlikely, even in the distant future. “Personality and intelligence are the products of dozens of genes, along with environmental influences,” Anderson says. “Changing them is just too complicated.”
- Cancer--This complex disease will continue to kill and cripple us in the next century, but it will be more curable. The National Cancer Institute foresees that, if current research strategies succeed, cure rates should rise to an average of 75% by the year 2000, up from about 50% today.
Research is progressing in dozens of directions. Scientists now know that some cancers are triggered by oncogenes, normal genes that turn malignant. They are starting to attack cancer with cells called monoclonal antibodies. These single-purpose molecules, armed with radioactive isotopes or drugs, can seek out and destroy a tumor.
New Approach
Other pioneer treatments seek to exploit the body’s natural defenses against malignancies. Research on immune substances known as the tumor necrosis factor, which destroys cancerous cells while leaving normal cells intact, may lead to radical new approaches to cancer therapy.
Combinations of surgery, radiation and chemotherapy, commonly used today, will continue to be staples of future cancer treatment, the specialists say, but they will be more refined and humane. “One of the main advances over the next 15 years will be a better way to determine who will respond to chemotherapy and who won’t,” predicts Dr. Bruce A. Chabner of the National Cancer Institute.
By 2000, some cancers, especially breast and ovarian cancers, should be highly curable, but lung cancer will remain a major killer. And the AIDS ( acquired immune deficiency syndrome) virus, which can lead to malignancies, is a worrisome question mark in future cancer rates, Chabner says.
“We’ll go about controlling cancer one disease at a time,” he says. But there probably will be no general cure.
- Artificial organs--Like a repaired car, the human body of 2000 will be made up of replaceable parts. “There is no organ which won’t be replaced in the future,” says Dr. Pierre Galletti, who has developed artificial organs at Brown University.
Parts that will commonly be replaced in the future include heart, lungs, kidney, pancreas, blood vessels, ears and, possibly, eyes. Eventually, Galletti says, man-made parts will replace the liver and even sections of the brain and nervous system.
Tomorrow’s artificial organs will be made of more sophisticated materials than today’s. “Bioartificial organs,” hybrids of natural transplants and artificial parts, may help stop tissue rejection by encapsulating donor material in plastic. Mainly because of a donor shortage, natural-heart transplants will wane, says Dr. Willem J. Kolff of the University of Utah. Soon after 2000, he believes, thousands of Americans will live with miniaturized artificial hearts.
