Chapter 3: Biomedical Technologies
A Robust Economic Force
GPS is now a dual-use
technology with civilian uses
that rival its continuing military role.
President Clinton announced in 1996 that the U.S. government would continue
providing GPS signals to the world free of direct user fees, as a public good.
GPS has since developed into a multi-billion-dollar international industry,
creating thousands of new jobs while saving lives and bringing many other
benefits. The number of companies identifying themselves as providers of some
sort of GPS-related goods or services has grown from 109 firms in 1992 to 301
firms in 1997. Even though relatively few of these firms compete to provide the
core GPS technology, a large number of firms provide GPS-enhanced products and
value-added services. The technology has clearly carved out a crucial role for
itself in the global information infrastructure. The precise GPS timing signals
that help synchronize global information networks of fiber optics, coaxial
cable, copper wire, radio, and communication satellites have become essential
to daily commerce.
Like many of the other technologies covered in this report,
global positioning — in both its history and
its current uses –
draws on the breakthroughs in the Information Technology field; we highlight it
here mainly because of its amazing economic promise. The global GPS market,
currently estimated at more than
$2 billion per year, is projected to
expand to $30 billion annually before 2030. GPS receivers and transmitters may
soon be smaller than credit cards — and cheap enough for use in almost any
vehicle, cell phone, or pocket, for that matter. With every square yard on
Earth measured and labeled with an address, and with computerized databases
available that give latitude and longitude as well as addresses, it's
conceivable that no one will ever need to ask directions again.
The United States has seen amazing changes in biomedical
technologies over the past 100 years. We have come from the family
doctor's signature black bag in the first half of the century to the
powerful scanning equipment of the modern medical center; from surgical saws to
the lasers, endoscopes, and angioplasty of today's operating rooms; from
tens of thousands dying in influenza epidemics to hundreds of thousands of
seniors receiving their annual flu shots; and from an average life expectancy
of about 49 years to our present expectancy of 75 years.
Medicine saves lives and relieves suffering. It embodies for
many of us the greatest achievements of science and technology. The rapid
progress in medicine has come from life sciences — such as biology and
genetics — but also from physics, math, and many other fields of science
and engineering.
|
Hello... Is the Doctor In?
Dr. Jerri Nielsen was a part of the National Science
Foundation-funded research mission in Antarctica.
Millions of Americans received their first introduction
to telemedicine in the summer of 1999 by following the news story of Dr. Jerri
Nielsen, 47. Dr. Nielsen, who was serving at the U.S. Amundsen-Scott South Pole
research station, discovered a lump in her breast during a routine
self-examination. She conducted telephone consultations with doctors via
satellite. On their advice, medical supplies were air-dropped, with which Dr.
Nielsen treated herself for several months until warmer weather permitted her
to be airlifted out safely.
Less dramatic telemedicine occurs daily. Some doctors
regularly e-mail medical images such as CAT scans to colleagues for review. In
remote rural areas, telemedicine can mean the difference between life and
death. For example, a specialist at a North Carolina University Hospital was
able to diagnose a patient's hairline spinal fracture at a distance, using
telemedicine video imaging. The patient avoided paralysis because treatment was
done on-site without physically transporting the patient to the specialist, who
was located a great distance away.
As the practice of telemedicine spreads, doctors may be
speaking literally when they say, “Call me in the morning and let me know
if you feel better.” |
Contributions from Physical Sciences
For example, over
the past 25 years physicists have developed revolutionary imaging technologies
that have allowed us to see deeper and deeper into the materials and processes
of life itself. Doctors are now using non-invasive means of looking into the
human body to diagnose a wide variety of diseases — including cancer,
multiple sclerosis, Alzheimer's disease, stroke, heart failure, and
vascular disease. CAT (Computer-Assisted Tomography) scans combine X-rays with
computer technology to create cross-sectional images of the patient's
body, which are then assembled into a three-dimensional picture that displays
organs, bones, and tissues in great detail. Magnetic Resonance Imaging (MRI)
scanners use magnets and radio waves instead of X-rays to generate images that
provide an even better view of soft tissues, such as the brain or spinal cord.
Ultrasound images, produced by very-high-frequency sound waves, can help
doctors visualize a developing fetus, detect tumors and organ abnormalities,
and identify women at risk of developing osteoporosis. Imaging technologies
have also greatly helped in early detection of breast cancer, which claims the
lives of nearly 42,000 American women each year. The deeper and smaller we see,
the more we understand how life processes work on their most fundamental
level.
Mathematics and computer science have greatly contributed to
biomedicine through information technology. Much of today's imaging
technology relies on microprocessors and software. Computers are also making it
easier for researchers to collect, analyze, and share data in research and
in telemedicine, and to model biological systems to project likely outcomes
more accurately. It would be impossible for scientists to sequence the entire
human genome without the information processing power of supercomputers. And
information technologies have provided essential tools to collect and analyze
data for epidemiological research that helps us understand the
distribution
of disease and to develop clinical and public health interventions.
Improving the health of all Americans requires a broad
spectrum of basic research across all the scientific disciplines, often drawing
upon tools developed in the physical sciences. Here a laser is used to treat
eye disease, before (left) and after (right).
Another development from the physical sciences, the laser, has
made the scalpel unnecessary in many kinds
of surgery. Laser surgery
reduces pain and trauma for the patient, speeds healing — thereby
shortening costly hospital stays — and improves the accuracy of certain
surgical procedures. Most notably, eye surgery has been revolutionized by this
new technology. Precision lasers have been used to halt, and in some cases
reverse, diabetic retinopathy, a dangerous complication of diabetes and the
leading cause of new cases of blindness in adults. Lasers can also be used to
repair small tears in the retina, preventing retinal detachment, and also to
provide follow-up treatment to patients after cataract surgery. Most recently,
ophthalmologists have begun to use lasers to correct nearsightedness, in a
procedure called LASIK (laser in situ keratomileusis). Not only is laser eye
surgery effective, but it is fast and relatively painless.
|
A Powerful New Prevention Tool
The vaccine against Hemophilus influenza type b (Hib)
meningitis provides the means to completely eliminate this disease from the
United States within the next few years. This turnaround is largely a result of
basic scientific research in molecular biology. For years this disease struck
15,000 to 20,000 U.S. children each year — almost as many as polio at its
peak. It killed 10 percent and left one-third deaf and another one-third
mentally retarded, making it this country's leading cause of acquired
mental retardation. Fortunately, two NIH scientists made a discovery about how
to make infants' bodies fight the disease, a discovery that led to the
development of a safe and effective vaccine. The vaccine, routinely
administered to babies only two months old, is saving more than $350 million
per year in avoided infections, and the incidence of Hib has declined by 95
percent since 1988. With greater use of the vaccine across the country, we have
the hope of completely eliminating Hib meningitis. |
Contributions from Life Sciences
Of course, the
biomedical revolution also sprang from fundamental advances in our knowledge of
the life sciences, particularly knowledge of genetics. Between 1665, when
Robert Hooke first observed cells, and the middle of this century, researchers
learned that heredity is controlled by genes, that genes are located on
chromosomes, and that genes are made from deoxyribonucleic acid (DNA). In 1953,
Watson and Crick discovered that the structure of DNA, which is common to all
life on Earth, is a double helix. That breakthrough swiftly cascaded into new
techniques that allow researchers and clinicians to control biological
processes in very precise ways.
Today industrial-scale production of insulin for diabetics is
possible because scientists learned how to cut and paste the human insulin into
bacteria that can produce large quantities of the substance inexpensively. Gene
transfer techniques are also used to produce antibodies that can attack
cancerous tumors directly or deliver lethal doses of drugs to tumors without
damaging surrounding tissue. Many of today's vaccines — which save $6
to $16 in medical costs for every dollar spent on production — come from
genetic engineering.
Knowledge of genetics will be further extended by the Human
Genome Project, an ambitious international effort to determine the complete
human DNA sequence, funded by the National Institutes of Health, the Department
of Energy, and the United Kingdom's Wellcome Trust. A map of the human
genome published in October 1998 contains over 30,000 genes, almost twice as
many genes as the map published in 1996. The work of the Human Genome Project
has led to development of tests that doctors are already using for screening
and diagnosing disease.
The HGP includes an important new research component that
focuses on the ethical, legal, and social implications (ELSI) of genetic
research. This program will help ensure that developments in genome science and
technology take account of values such as privacy and affordable health care.
The ELSI program also will serve as a model for other technological initiatives
that raise concerns about established cultural norms even as they offer
tremendous advantages.
|
Healthy Hearts--Right From the Start
Over the past two decades, medical science has managed
to reduce deaths from stroke by 59 percent and deaths from heart attack by 53
percent. One major reason for this success has been the development of drugs
that combat hypertension. A concentrated research effort that combined the
efforts of the Federal government, pharmaceutical companies, voluntary health
agencies, and private foundations contributed to this feat. Although these
decreases in deaths are encouraging, we still don't know enough about how
hypertension works. Preventing this condition is still an elusive goal.
In addition to modern drug therapy for heart disease
patients, medical scientists consistently advise careful eating habits, since
diet can contribute to the risk of cardiovascular disease. The long-established
eating habits of adults can be extremely resistant to change. But it may be
possible to teach younger Americans to eat more nutritious foods. A study
supported by the National Heart, Lung, and Blood Institute at the National
Institutes of Health suggests that an intensive school and family-based
intervention program can have lasting effects.
More than 5,000 grade-school students from nearly 100
ethnically and racially diverse elementary schools
in California,
Louisiana, Minnesota, and Texas participated in the original CATCH (Child and
Adolescent Trial for Cardiovascular Health) Study between 1991 and 1994. The
children learned to read labels; to select “Go,” “Slow,”
and “Whoa!” foods; and to prepare healthy snacks. They ate
heart-healthy school lunches, participated in more moderate to vigorous
activities in PE classes, and engaged their families in entertaining activities
and games promoting healthy eating and exercise behaviors.
In a follow-up study, researchers found that the
students who received the health promotion intervention in grades three through
five maintained a diet significantly lower in total fat and saturated fat and
continued to
pursue more vigorous physical activity levels than did
students in the control groups. These results suggest that schools can be an
important place to help young people establish habits that may help prevent the
early onset of
cardiovascular disease — the leading cause of death
among Americans. |
|