12 December 2008
Artificial heart
The invention:
The first successful artificial heart, the Jarvik-7, has
helped to keep patients suffering from otherwise terminal heart
disease alive while they await human heart transplants.
The people behind the invention:
Robert Jarvik (1946- ), the main inventor of the Jarvik-7
William Castle DeVries (1943- ), a surgeon at the University
of Utah in Salt Lake City
Barney Clark (1921-1983), a Seattle dentist, the first recipient of
the Jarvik-7
Early Success
The Jarvik-7 artificial heart was designed and produced by researchers
at the University of Utah in Salt Lake City; it is named for
the leader of the research team, Robert Jarvik. An air-driven pump
made of plastic and titanium, it is the size of a human heart. It is made
up of two hollow chambers of polyurethane and aluminum, each
containing a flexible plastic membrane. The heart is implanted in a
human being but must remain connected to an external air pump by
means of two plastic hoses. The hoses carry compressed air to the
heart, which then pumps the oxygenated blood through the pulmonary
artery to the lungs and through the aorta to the rest of the body.
The device is expensive, and initially the large, clumsy air compressor
had to be wheeled from room to room along with the patient.
The device was new in 1982, and that same year Barney Clark, a
dentist from Seattle, was diagnosed as having only hours to live.
His doctor, cardiac specialistWilliam Castle DeVries, proposed surgically
implanting the Jarvik-7 heart, and Clark and his wife agreed.
The Food and Drug Administration (FDA), which regulates the use
of medical devices, had already given DeVries and his coworkers
permission to implant up to seven Jarvik-7 hearts for permanent use.
The operation was performed on Clark, and at first it seemed quite
successful. Newspapers, radio, and television reported this medical
breakthrough: the first time a severely damaged heart had been re-placed by a totally artificial heart. It seemed DeVries had proved that an artificial heart could be almost as good as a human heart.
Soon after Clark’s surgery, DeVries went on to implant the device placed by a totally artificial heart.in several other patients with serious heart disease. For a time, all of them survived the surgery. As a result, DeVries was offered a position
at Humana Hospital in Louisville, Kentucky. Humana offered
to pay for the first one hundred implant operations
The Controversy Begins
In the three years after DeVries’s operation on Barney Clark,
however, doubts and criticism arose. Of the people who by then had
received the plastic and metal device as a permanent replacement
for their own diseased hearts, three had died (including Clark) and
four had suffered serious strokes. The FDAasked Humana Hospital
and Symbion (the company that manufactured the Jarvik-7) for
complete, detailed histories of the artificial-heart recipients.
It was determined that each of the patients who had died or been
disabled had suffered from infection. Life-threatening infection, or
“foreign-body response,” is a danger with the use of any artificial
organ. The Jarvik-7, with its metal valves, plastic body, and Velcro
attachments, seemed to draw bacteria like a magnet—and these
bacteria proved resistant to even the most powerful antibiotics.
By 1988, researchers had come to realize that severe infection was
almost inevitable if a patient used the Jarvik-7 for a long period of
time. As a result, experts recommended that the device be used for
no longer than thirty days.
Questions of values and morality also became part of the controversy
surrounding the artificial heart. Some people thought that it
was wrong to offer patients a device that would extend their lives
but leave them burdened with hardship and pain. At times DeVries
claimed that it was worth the price for patients to be able live another
year; at other times, he admitted that if he thought a patient
would have to spend the rest of his or her life in a hospital, he would
think twice before performing the implant.
There were also questions about “informed consent”—the patient’s
understanding that a medical procedure has a high risk of
failure and may leave the patient in misery even if it succeeds.
Getting truly informed consent from a dying patient is tricky, because,
understandably, the patient is probably willing to try anything.
The Jarvik-7 raised several questions in this regard:Was the ordeal worth the risk? Was the patient’s suffering justifiable? Who should make the decision for or against the surgery: the patient, the researchers, or a government agency?
Also there was the issue of cost. Should money be poured into expensive,
high-technology devices such as the Jarvik heart, or should
it be reserved for programs to help prevent heart disease in the first
place? Expenses for each of DeVries’s patients had amounted to
about one million dollars.
Humana’s and DeVries’s earnings were criticized in particular.
Once the first one hundred free Jarvik-7 implantations had been
performed, Humana Hospital could expect to make large amounts
of money on the surgery. By that time, Humana would have so
much expertise in the field that, though the surgical techniques
could not be patented, it was expected to have a practical monopoly.
DeVries himself owned thousands of shares of stock in Symbion.
Many people wondered whether this was ethical.
Consequences
Given all the controversies, in December of 1985 a panel of experts
recommended that the FDAallow the experiment to continue,but only with careful monitoring. Meanwhile, cardiac transplantation was becoming easier and more common. By the end of 1985, almost twenty-six hundred patients in various countries had received human heart transplants, and 76 percent of these patients had survived
for at least four years. When the demand for donor hearts exceeded the supply, physicians turned to the Jarvik device and other artificial hearts to help see patients through the waiting period.
Experience with the Jarvik-7 made the world keenly aware of
how far medical science still is from making the implantable permanent
mechanical heart a reality. Nevertheless, the device was a
breakthrough in the relatively new field of artificial organs. Since
then, other artificial body parts have included heart valves, blood
vessels, and inner ears that help restore hearing to the deaf.
William C. DeVries
William Castle DeVries did not invent the artificial heart
himself; however, he did develop the procedure to implant it.
The first attempt took him seven and a half hours, and he
needed fourteen assistants. Asuccess, the surgery made DeVries
one of the most talked-about doctors in the world.
DeVries was born in Brooklyn,NewYork, in 1943. His father,
a Navy physician, was killed in action a few months later, and
his mother, a nurse, moved with her son to Utah. As a child
DeVries showed both considerable mechanical aptitude and
athletic prowess. He won an athletic scholarship to the University
of Utah, graduating with honors in 1966. He entered the
state medical school and there met Willem Kolff, a pioneer in
designing and testing artificial organs. Under Kolff’s guidance,
DeVries began performing experimental surgeries on animals
to test prototype mechanical hearts. He finished medical school
in 1970 and from 1971 until 1979 was an intern and then a resident
in surgery at the Duke University Medical Center in North
Carolina.
DeVries returned to the University of Utah as an assistant
professor of cardiovascular and thoracic surgery. In the meantime,
Robert K. Jarvik had devised the Jarvik-7 artificial heart.
DeVries experimented, implanting it in animals and cadavers
until, following approval from the Federal Drug Administration,
Barney Clark agreed to be the first test patient. He died 115
days after the surgery, having never left the hospital. Although
controversy arose over the ethics and cost of the procedure,
more artificial heart implantations followed, many by DeVries.
Long administrative delays getting patients approved for
surgery at Utah frustrated DeVries, so he moved to Humana
Hospital-Audubon in Louisville, Kentucky, in 1984 and then
took a professorship at the University of Louisville. In 1988 he
left experimentation for a traditional clinical practice. The FDA
withdrew its approval for the Jarvik-7 in 1990.
In 1999 DeVries retired from practice, but not from medicine.
The next year he joined the Army Reserve and began teaching
surgery at the Walter Reed Army Medical Center.
06 December 2008
Artificial blood
The invention:
Aperfluorocarbon emulsion that serves as a blood
plasma substitute in the treatment of human patients.
The person behind the invention:
Ryoichi Naito (1906-1982), a Japanese physician.
Blood Substitutes
The use of blood and blood products in humans is a very complicated
issue. Substances present in blood serve no specific purpose
and can be dangerous or deadly, especially when blood or blood
products are taken from one person and given to another. This fact,
combined with the necessity for long-term blood storage, a shortage
of donors, and some patients’ refusal to use blood for religious reasons,
brought about an intense search for a universal bloodlike substance.
The life-sustaining properties of blood (for example, oxygen transport)
can be entirely replaced by a synthetic mixture of known chemicals.
Fluorocarbons are compounds that consist of molecules containing
only fluorine and carbon atoms. These compounds are interesting
to physiologists because they are chemically and pharmacologically
inert and because they dissolve oxygen and other gases.
Studies of fluorocarbons as blood substitutes began in 1966,
when it was shown that a mouse breathing a fluorocarbon liquid
treated with oxygen could survive. Subsequent research involved
the use of fluorocarbons to play the role of red blood cells in transporting
oxygen. Encouraging results led to the total replacement of
blood in a rat, and the success of this experiment led in turn to trials
in other mammals, culminating in 1979 with the use of fluorocarbons
in humans.
Clinical Studies
The chemical selected for the clinical studies was Fluosol-DA,
produced by the Japanese Green Cross Corporation. Fluosol-DA
consists of a 20 percent emulsion of two perfluorocarbons (perfluorodecalin
and perfluorotripopylamine), emulsifiers, and salts
that are included to give the chemical some of the properties of
blood plasma. Fluosol-DA had been tested in monkeys, and it had
shown a rapid reversible uptake and release of oxygen, a reasonably
rapid excretion, no carcinogenicity or irreversible changes in the animals’
systems, and the recovery of blood components to normal
ranges within three weeks of administration.
The clinical studies were divided into three phases. The first
phase consisted of the administration of Fluosol-DA to normal human
volunteers. Twelve healthy volunteers were administered the
chemical, and the emulsion’s effects on blood pressure and composition
and on heart, liver, and kidney functions were monitored. No
adverse effects were found in any case. The first phase ended in
March, 1979, and based on its positive results, the second and third
phases were begun in April, 1979.
Twenty-four Japanese medical institutions were involved in the
next two phases. The reasons for the use of Fluosol-DA instead of
blood in the patients involved were various, and they included refusal
of transfusion for religious reasons, lack of compatible blood,
“bloodless” surgery for protection from risk of hepatitis, and treatment
of carbon monoxide intoxication.
Among the effects noticed by the patients were the following: a
small increase in blood pressure, with no corresponding effects on
respiration and body temperature; an increase in blood oxygen content;
bodily elimination of half the chemical within six to nineteen
hours, depending on the initial dose administered; no change in
red-cell count or hemoglobin content of blood; no change in wholeblood
coagulation time; and no significant blood-chemistry changes.
These results made the clinical trials a success and opened the door
for other, more extensive ones.
IMPACT
Perfluorocarbon emulsions were initially proposed as oxygencarrying
resuscitation fluids, or blood substitutes, and the results of
the pioneering studies show their success as such. Their success in
this area, however, led to advanced studies and expanded use of these compounds in many areas of clinical medicine and biomedical
research.
Perfluorocarbon emulsions are useful in cancer therapy, because
they increase the oxygenation of tumor cells and therefore sensitize
them to the effects of radiation or chemotherapy. Perfluorocarbons
can also be used as “contrasting agents” to facilitate magnetic resonance
imaging studies of various tissues; for example, the uptake of
particles of the emulsion by the cells of malignant tissues makes it
possible to locate tumors. Perfluorocarbons also have a high nitrogen
solubility and therefore can be used to alleviate the potentially
fatal effects of decompression sickness by “mopping up” nitrogen
gas bubbles from the circulation system. They can also be used to
preserve isolated organs and amputated extremities until they can
be reimplanted or reattached. In addition, the emulsions are used in
cell cultures to regulate gas supply and to improve cell growth and
productivity.
The biomedical applications of perfluorocarbon emulsions are
multidisciplinary, involving areas as diverse as tissue imaging, organ
preservation, cancer therapy, and cell culture. The successful
clinical trials opened the door for new applications of these
compounds, which rank among the most versatile compounds exploited
by humankind.
03 December 2008
Aqualung
The invention:
A device that allows divers to descend hundreds of
meters below the surface of the ocean by enabling them to carry
the oxygen they breathe with them.
The people behind the invention:
Jacques-Yves Cousteau (1910-1997), a French navy officer,
undersea explorer, inventor, and author.
Émile Gagnan, a French engineer who invented an automatic
air-regulating device.
The Limitations of Early Diving
Undersea dives have been made since ancient times for the purposes
of spying, recovering lost treasures from wrecks, and obtaining
natural treasures (such as pearls). Many attempts have been made
since then to prolong the amount of time divers could remain underwater.
The first device, described by the Greek philosopher Aristotle
in 335 b.c.e., was probably the ancestor of the modern snorkel. It was
a bent reed placed in the mouth, with one end above the water.
In addition to depth limitations set by the length of the reed,
pressure considerations also presented a problem. The pressure on
a diver’s body increases by about one-half pound per square centimeter
for every meter ventured below the surface. After descending
about 0.9 meter, inhaling surface air through a snorkel becomes difficult
because the human chest muscles are no longer strong enough
to inflate the chest. In order to breathe at or below this depth, a diver
must breathe air that has been pressurized; moreover, that pressure
must be able to vary as the diver descends or ascends.
Few changes were possible in the technology of diving until air
compressors were invented during the early nineteenth century.
Fresh, pressurized air could then be supplied to divers. At first, the
divers who used this method had to wear diving suits, complete
with fishbowl-like helmets. This “tethered” diving made divers relatively
immobile but allowed them to search for sunken treasure or
do other complex jobs at great depths.
The Development of Scuba Diving
The invention of scuba gear gave divers more freedom to
move about and made them less dependent on heavy equipment.
(“Scuba” stands for self-contained underwater breathing apparatus.)
Its development occurred in several stages. In 1880, Henry
Fleuss of England developed an outfit that used a belt containing
pure oxygen. Belt and diver were connected, and the diver breathed
the oxygen over and over. Aversion of this system was used by the
U.S. Navy in World War II spying efforts. Nevertheless, it had serious
drawbacks: Pure oxygen was toxic to divers at depths greater
than 9 meters, and divers could carry only enough oxygen for relatively
short dives. It did have an advantage for spies, namely, that
the oxygen—breathed over and over in a closed system—did not
reach the surface in the form of telltale bubbles.
The next stage of scuba development occurred with the design
of metal tanks that were able to hold highly compressed air.
This enabled divers to use air rather than the potentially toxic
pure oxygen. More important, being hooked up to a greater supply
of air meant that divers could stay under water longer. Initially,
the main problem with the system was that the air flowed continuously
through a mask that covered the diver’s entire face. This process
wasted air, and the scuba divers expelled a continual stream
of air bubbles that made spying difficult. The solution, according to
Axel Madsen’s Cousteau (1986), was “a valve that would allow inhaling
and exhaling through the same mouthpiece.”
Jacques-Yves Cousteau’s father was an executive for Air Liquide—
France’s main producer of industrial gases. He was able to direct
Cousteau to Émile Gagnan, an engineer at thecompany’s Paris laboratory
who had been developing an automatic gas shutoff valve for Air
Liquide. This valve became the Cousteau-Gagnan regulator, a breathing
device that fed air to the diver at just the right pressure whenever
he or she inhaled.With this valve—and funding from Air Liquide—Cousteau and
Gagnan set out to design what would become the Aqualung. The
first Aqualungs could be used at depths of up to 68.5 meters. During
testing, however, the dangers of Aqualung diving became apparent.
For example, unless divers ascended and descended in slow stages,
it was likely that they would get “the bends” (decompression sickness),
the feared disease of earlier, tethered deep-sea divers. Another
problem was that, below 42.6 meters, divers encountered nitrogen
narcosis. (This can lead to impaired judgment that may cause
fatal actions, including removing a mouthpiece or developing an
overpowering desire to continue diving downward, to dangerous
depths.)Cousteau believed that the Aqualung had tremendous military
potential. DuringWorldWar II, he traveled to London soon after the
Normandy invasion, hoping to persuade the Allied Powers of its
usefulness. He was not successful. So Cousteau returned to Paris
and convinced France’s new government to use Aqualungs to locate
and neutralize underwater mines laid along the French coast by
the German navy. Cousteau was commissioned to combine minesweeping
with the study of the physiology of scuba diving. Further
research revealed that the use of helium-oxygen mixtures increased
to 76 meters the depth to which a scuba diver could go without suffering
nitrogen narcosis.
Impact
One way to describe the effects of the development of the Aqualung
is to summarize Cousteau’s continued efforts to the present. In
1946, he and Philippe Tailliez established the Undersea Research
Group of Toulon to study diving techniques and various aspects of
life in the oceans. They studied marine life in the Red Sea from 1951
to 1952. From 1952 to 1956, they engaged in an expedition supported
by the National Geographic Society. By that time, the Research
Group had developed many techniques that enabled them to
identify life-forms and conditions at great depths.
Throughout their undersea studies, Cousteau and his coworkers
continued to develop better techniques for scuba diving, for recording
observations by means of still and television photography, and
for collecting plant and animal specimens. In addition, Cousteau
participated (with Swiss physicist Auguste Piccard) in the construction
of the deep-submergence research vehicle, or bathyscaphe. In
the 1960’s, he directed a program called Conshelf, which tested a
human’s ability to live in a specially built underwater habitat. He
also wrote and produced films on underwater exploration that attracted,
entertained, and educated millions of people.
Cousteau has won numerous medals and scientific distinctions.
These include the Gold Medal of the National Geographic Society
(1963), the United Nations International Environment Prize (1977),
membership in the American and Indian academies of science (1968
and 1978, respectively), and honorary doctor of science degrees
from the University of California, Berkeley (1970), Harvard University
(1979), and Rensselaer Polytechnical Institute (1979).
30 November 2008
Apple II computer
The invention:
The first commercially available, preassembled
personal computer, the Apple II helped move computers out of
the workplace and into the home.
The people behind the invention:
Stephen Wozniak (1950- ), cofounder of Apple and designer
of the Apple II computer
Steven Jobs (1955-2011 ), cofounder of Apple
Regis McKenna (1939- ), owner of the Silicon Valley public
relations and advertising company that handled the Apple
account
Chris Espinosa (1961- ), the high school student who wrote
the BASIC program shipped with the Apple II
Randy Wigginton (1960- ), a high school student and Apple
software programmer
27 November 2008
Antibacterial drugs
Mechanisms of genetic resistance to antimicrobial agents:
Bacteria have developed, or will develop, genetic resistance to all known antimicrobial agents that are now in the marketplace. The five main mechanisms that bacteria use to resist antibacterial drugs are shown in the figure.
a | The site of action (enzyme, ribosome or cell-wall precursor) can be altered. For example, acquiring a plasmid or transposon that codes for a resistant dihydrofolate reductase confers trimethoprim resistance to bacteria52.
b | The inhibited steps can be by-passed.
c | Bacteria can reduce the intracellular concentration of the antimicrobial agent, either by reducing membrane permeability, for example, as shown by Pseudomonas aeruginosa53, or by active efflux of the agent54.
d | They can inactivate the drug. For example, some bacteria produce beta-lactamase, which destroys the penicillin beta-lactam ring50, 51 .
e | The target enzyme can be overproduced by the bacteria.
The invention:
Sulfonamides and other drugs that have proved effective
in combating many previously untreatable bacterial diseases.
The people behind the invention:
Gerhard Domagk (1895-1964), a German physician who was
awarded the 1939 Nobel Prize in Physiology or Medicine
Paul Ehrlich (1854-1915), a German chemist and bacteriologist
who was the cowinner of the 1908 Nobel Prize in Physiology
or Medicine.
The Search for Magic Bullets
Although quinine had been used to treat malaria long before the
twentieth century, Paul Ehrlich, who discovered a large number of
useful drugs, is usually considered the father of modern chemotherapy.
Ehrlich was familiar with the technique of using dyes to stain
microorganisms in order to make them visible under a microscope,
and he suspected that some of these dyes might be used to poison
the microorganisms responsible for certain diseases without hurting
the patient. Ehrlich thus began to search for dyes that could act
as “magic bullets” that would destroy microorganisms and cure
diseases. From 1906 to 1910, Ehrlich tested numerous compounds
that had been developed by the German dye industry. He eventually
found that a number of complex trypan dyes would inhibit the
protozoans that caused African sleeping sickness.
Ehrlich and his coworkers also synthesized hundreds of organic
compounds that contained arsenic. In 1910, he found that one of
these compounds, salvarsan, was useful in curing syphilis, a sexually
transmitted disease caused by the bacterium Treponema. This
was an important discovery, because syphilis killed thousands of
people each year. Salvarsan, however, was often toxic to patients,
because it had to be taken in large doses for as long as two years to
effect a cure. Ehrlich thus searched for and found a less toxic arsenic
compound, neosalvarsan, which replaced salvarsan in 1912.
In 1915, tartar emetic (a compound containing the metal antimony)
was found to be useful in treating kala-azar, which was
caused by a protozoan. Kala-azar affected millions of people in Africa,
India, and Asia, causing much suffering and many deaths each
year. Two years later, it was discovered that injection of tartar emetic
into the blood of persons suffering from bilharziasis killed the
flatworms infecting the bladder, liver, and spleen. In 1920, suramin,
a colorless compound developed from trypan red, was introduced
to treat African sleeping sickness. It was much less toxic to the patient
than any of the drugs Ehrlich had developed, and a single dose
would give protection for more than a month. From the dye methylene
blue, chemists made mepacrine, a drug that was effective
against the protozoans that cause malaria. This chemical was introduced
in 1933 and used duringWorldWar II; its principal drawback
was that it could cause a patient’s skin to become yellow.
Well Worth the Effort
Gerhard Domagk had been trained in medicine, but he turned to
research in an attempt to discover chemicals that would inhibit or
kill microorganisms. In 1927, he became director of experimental
pathology and bacteriology at the Elberfeld laboratories of the German
chemical firm I. G. Farbenindustrie. Ehrlich’s discovery that
trypan dyes selectively poisoned microorganisms suggested to Domagk
that he look for antimicrobials in a new group of chemicals
known as azo dyes. A number of these dyes were synthesized
from sulfonamides and purified by Fritz Mietzsch and Josef Klarer.
Domagk found that many of these dyes protected mice infected
with the bacteria Streptococcus pyogenes. In 1932, he discovered that
one of these dyes was much more effective than any tested previously.
This red azo dye containing a sulfonamide was named prontosil
rubrum.
From 1932 to 1935, Domagk began a rigorous testing program to
determine the effectiveness and dangers of prontosil use at different
doses in animals. Since all chemicals injected into animals or humans
are potentially dangerous, Domagk determined the doses that
harmed or killed. In addition, he worked out the lowest doses that
would eliminate the pathogen. The firm supplied samples of the drug to physicians to carry out clinical trials on humans. (Animal
experimentation can give only an indication of which chemicals
might be useful in humans and which doses are required.)
Domagk thus learned which doses were effective and safe. This
knowledge saved his daughter’s life. One day while knitting, Domagk’s
daughter punctured her finger with a needle and was infected
with a virulent bacteria, which quickly multiplied and spread
from the wound into neighboring tissues. In an attempt to alleviate
the swelling, the infected area was lanced and allowed to drain, but
this did not stop the infection from spreading. The child became
critically ill with developing septicemia, or blood poisoning.
In those days, more than 75 percent of those who acquired blood
infections died. Domagk realized that the chances for his daughter’s
survival were poor. In desperation, he obtained some of the powdered
prontosil that had worked so well on infected animals. He extrapolated
from his animal experiments how much to give his
daughter so that the bacteria would be killed but his daughter
would not be poisoned. Within hours of the first treatment, her fever
dropped, and she recovered completely after repeated doses of
prontosil.
Impact
Directly and indirectly, Ehrlich’s and Domagk’s work served to
usher in a new medical age. Prior to the discovery that prontosil
could be use to treat bacterial infection and the subsequent development
of a series of sulfonamides, or “sulfa drugs,” there was no
chemical defense against this type of disease; as a result, illnesses
such as streptococcal infection, gonorrhea, and pneumonia held terrors
of which they have largely been shorn.Asmall injury could easily
lead to death.
By following the clues presented by the synthetic sulfa drugs and
how they worked to destroy bacteria, other scientists were able to
develop an even more powerful type of drug, the antibiotic. When
the American bacteriologist Rene Dubos discovered that natural organisms
could also be used to fight bacteria, interest was renewed in
an earlier discovery by the Scottish bacteriologist Sir Alexander: the
development of penicillin.
Antibiotics such as penicillin and streptomycin have become
some of the most important tools in fighting disease. Antibiotics
have replaced sulfa drugs for most uses, in part because they cause
fewer side effects, but sulfa drugs are still used for a handful of purposes.
Together, sulfonamides and antibiotics have offered the possibility
of a cure to millions of people who previously would have
had little chance of survival.
23 November 2008
Amniocentesis
19 November 2008
Ammonia
17 November 2008
Alkaline storage battery
The invention:
The nickel-iron alkaline battery was a lightweight,
inexpensive portable power source for vehicles with electric motors.
The people behind the invention:
Thomas Alva Edison (1847-1931), American chemist, inventor,
and industrialist
Henry Ford (1863-1947), American inventor and industrialist
Charles F. Kettering (1876-1958), American engineer and
inventor
15 November 2008
Airplane
The invention:
The first heavier-than-air craft to fly, the airplane
revolutionized transportation and symbolized the technological
advances of the twentieth century.
The people behind the invention:
Wilbur Wright (1867-1912), an American inventor
Orville Wright (1871-1948), an American inventor
Octave Chanute (1832-1910), a French-born American civil
engineer
14 November 2008
Abortion pill
The invention:
RU-486 was the first commercially available drug that prevented fertilized eggs from implanting themselves in the walls of women’s uteruses.
The people behind the invention:
Étienne-Émile Baulieu (1926- ), a French biochemist and endocrinologist Georges Teutsch, a French chemist
Alain Bélanger a French chemist
Daniel Philibert, a French physicist and pharmacologist
RU-486 was the first commercially available drug that prevented fertilized eggs from implanting themselves in the walls of women’s uteruses.
The people behind the invention:
Étienne-Émile Baulieu (1926- ), a French biochemist and endocrinologist Georges Teutsch, a French chemist
Alain Bélanger a French chemist
Daniel Philibert, a French physicist and pharmacologist
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