a bold exploration of human anatomy
challenging centuries of accepted
beliefs a mysterious glow that pointed
the way to a startling new vision of the
world a miracle drug that saved the
lives of countless Allied soldiers the
killer behind an epidemic unmasked these
are among the greatest discoveries in
the history of Medicine
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each one a revolutionary breakthrough
that saved lives by pushing the
boundaries of knowledge by imagining the
unimaginable
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in ancient Greece the treatment of
disease was based more on philosophy
than in genuine understanding of human
anatomy surgical procedures were rare
and human dissection was not an accepted
practice as a result physicians had
little first-hand information about the
inside of the human body it wasn't until
the Renaissance that the science of
human anatomy was born a Belgian
physician Andres Vesalius shocked many
by deciding to investigate Anatomy by
dissecting human bodies bodies that he
was often forced to procure under cover
of night for medical students like
Mercedes who wanted to dissect they had
to just find bodies from outside of the
legal channels once the cells became a
professor at Padua
the person in charge of executions was
actually a friend of his so Vesalius
could even go in and observe the living
prisoners who are waiting execution and
say I want that one I want that one and
and then the person would be executed
according to dr. baile bill Vesalius was
determined to pass on the first-hand
knowledge that he had gained from his
skillful dissections by writing a book
on human anatomy the result was his de
human Accor porous fabrica on the
structure of the human body
first published in 1538 fabrica is
considered one of the greatest books in
medical literature it's regarded as one
of the greatest discoveries in medicine
because it contains the first accurate
description of the interior of the human
body this was the first major challenge
to the authority of the ancient Greek
physicians the book had a great sale
that must have been to a wealthy
literate public that went far beyond the
medical profession and the pictures are
very elaborately keyed in with the
written text so it just made knowledge
of human anatomy much more accessible
thanks to Vesalius the study of human
anatomy through dissection became an
essential component of medical training
and helped lead to our next great
discovery the human heart a muscle the
size of a fist beating more than a
hundred thousand times a day over 2
billion heartbeats by the time you turn
70 pumping more than five gallons of
blood a minute blood flows through the
body traveling a complex highway of
arteries and veins it's estimated that
if all the blood vessels in just one
human body were placed in a line they'd
reach some 60,000 miles more than twice
around the earth
but in the early part of the 17th
century how blood works in the body was
misunderstood the prevailing theory was
that it abdun flowed through the heart
by way of pores in the soft tissue among
those who believed in this theory was an
English physician named William Harvey
he was fascinated with the workings of
the heart the more he studied the
beating hearts of animals on his
dissecting table the more he realized
the accepted theory of blood flow
couldn't be right
quite explicitly says I began to think
whether the blood might have emotion as
it were in a circle and then he begins a
new paragraph and he says and this I
have to word found to be true in his
dissections harvey observed that the
heart had one-way valves that kept the
blood flowing in one direction some
valves let the blood in while others let
it out here was his great discovery the
heart he realized was pumping blood into
the arteries where it then circulated
through the veins coming full circle
back into the heart ready to start the
cycle all over again today it's obvious
that blood circulates in the human body
but in the 17th century William Harvey's
discovery was revolutionary this was
really striking at the very core of
traditional medical ideas and at the end
of his treatise Harvey says when I think
of the countless implications that this
will have for medicine I see a field of
almost unlimited possibilities Harvey's
discovery led to major advances in
anatomical research and surgery and
simple life-saving ones too
in operating rooms and trauma centers
around the world Surgical clamps are
used to stem the flow of blood and keep
a patient's circulation intact a simple
device but each one a reminder of
William Harvey's great discovery another
great discovery having to do with blood
occurred in Vienna in 1900 there was a
great enthusiasm throughout Europe for
transfusing blood and at first there
were claims that this had marvelous
therapeutic effects but this was
followed within months by reports of
people who died
why did some blood transfusions work and
others didn't
an Austrian physician named Karl
Landsteiner
was determined to find the answer he
makes blood samples from various
individuals and studied the effects in
some cases the samples mix safely but in
other combinations the blood clumped and
became sticky on closer examination
launched Steiner found that clumping
occurred when certain proteins called
antibodies in the recipients blood
bonded to other proteins called antigens
on the donors red blood cells for launch
Steiner this was the moment of discovery
he realized that not all human blood was
the same he determined that human blood
could be divided into four distinct
groups he called these blood groups a B
a B and O he realized that blood
transfusion could only be carried out
safely when people receive blood from
someone who shared the same blood group
the impact of launch Steiners discovery
was immediate within a few years blood
transfusions were being practiced around
the world saving countless lives by the
1950s accurate blood typing helped make
organ transplants possible
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today in the United States alone blood
transfusions are performed about once
every three seconds without them
it's estimated that four and a half
million Americans would die each year
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while the first great discoveries about
human anatomy enabled physicians to save
more lives there was little they could
do to reduce pain without anesthesia
surgery was a waking nightmare patients
were held down or lashed to a table
surgeons worked as quickly as possible
the sooner the torment was over the
better
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in 1811 one woman wrote of the ordeal
when the dreadful steel was plunged in
cutting through veins arteries flesh
nerves I needed no injunction not to
restrain my cries I began a scream that
lasted during the whole time so
excruciating was the agony surgery was a
last resort many people simply chose to
die rather than to have the surgeon cut
into them with his knife
according to dr. Hardin for centuries
various remedies were used to help ease
pain during surgery some like opium or
an extract from the Mandrake root were
narcotics by the 1840s several
individuals were on the trail of finding
a more effective and aesthetic in Boston
to dentists Horace Wells and William
Morton both of whom knew each other and
in Georgia a small-town doctor named
Crawford lon they experimented with two
chemicals thought to have the potential
for reducing pain nitrous oxide or
laughing gas and ether a liquid mix of
alcohol and sulfuric acid just who
discovered anaesthesia is still a matter
of debate
all three doctors claimed it
one of the first public demonstrations
of anesthesia occurred on October 16th
1846 William Morton had been
experimenting with ether for months
trying to find a dosage that would
enable a patient to undergo surgery
pain-free with a special device of his
own creation he convened a demonstration
before an audience of Boston surgeons
and medical students he administered
ether to a patient who was about to have
a tumor removed from his neck morton
waited the surgeon made the first
incision
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remarkably the patient did not cry out
after the surgery the patient reported
feeling nothing throughout the entire
operation and word quickly spread
surgical pain was conquered anesthesia
had been discovered despite the
discovery many people were reluctant to
use anesthesia some religions believe
that pain was to be tolerated not
relieved
especially during childbirth Queen
Victoria played a role in this in 1853
she was giving birth to Prince Leopold
and she asked for and was given
chloroform and found that it relieved
the pain of childbirth and shortly
thereafter women in general said I think
I'll have chloroform - it fits good
enough for the Queen it's good enough
for me
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it's also impossible to imagine life
without our next great discovery
imagine surgery without first being able
to see where to make the incision which
bone may be broken where the bullet may
be larger what pathological condition
may exist the ability to see inside the
human body without cutting it open was a
turning point in the history of Medicine
to find out more about it I paid a visit
to Betty Ann Holtzman kevlars a
professor of history at Yale University
the end of the 19th century people were
using electricity but they didn't
understand what it was this is a tube
which I believe is a copy of the one
made by the Siemens company which was
the one that would have been used by a
Rankine Renkin was German physicist
Vilhelm Renkin in 1895 he was
experimenting with a cathode ray tube an
evacuated glass cylinder a vacuum tube
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Renkin marveled at the glow created by
the Rays coming from the tube for one of
his experiments run cannon closed a tube
and black cardboard and darkened the
room then he turned on the tube
moments later something startled him
a photographic plate in his lab was
glowing so he realized that something
very unusual was going on and he knew
that the whatever the Ray that was
coming out of here was not a cathode ray
he also discovered that it didn't
respond to magnetism
he couldn't deflect it the way you could
cathode rays it was something altogether
new and he called it X for unknown like
in algebra absolutely Renkin had
accidentally discovered a radiation
unknown to science which he called
x-rays after having been rather
mysterious for several weeks he called
his wife down he said Bertha let me show
you what I'm doing because no one's
going to believe this and he had her put
her hand under the Ray and he took an
image of her hand while the image was a
lot like this picture and she is reputed
to have said I have seen my own death
because in those days you only saw a
skeleton after someone had died the idea
of seeing part of the body on an image
of a living person was just beyond
anybody's imagination yeah
It was as if a secret door had been
opened revealing a hidden universe
Lincoln had discovered a powerful new
technology one that led to a revolution
in medical diagnostics
in the history of science the discovery
of x-rays is the only discovery that was
made when no one was looking for it it
was totally by chance but as important
once it was discovered it was accepted
by everyone in the world there was no
controversy within a week or two our
world had changed today the legacy of
renkins discovery can be found in the
powerful technologies that followed in
its wake from the cat scan that helps
diagnose what ails us - NASA's Chandra
x-ray telescope which astronomers are
using to detect x-rays from the farthest
reaches of space all from a discovery
that happened by accident
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some discoveries like x-rays seem to
come out of the blue while others like
our next great discovery develop over
time with one scientist contributing to
the work of another
Vienna 1846 a city of beauty and culture
but at the end General Hospital
there was the specter of death many of
the women who came here to give birth
were dying because child bed fever an
infection of the uterus
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when dr. ignite Semmelweis came to work
at the hospital he was alarmed at the
scope of the problem and intrigued by a
curious discrepancy they had two wards
in one the mothers were delivered by
physicians and in the other the mothers
had their babies delivered by midwives
samo vice noted that in the ward where
the physicians delivered babies seven
percent of the mothers died from what
was called child bed fever in the ward
where the midwives delivered only 2% of
the mothers died from child bed fever
and his poverty because physicians to
have more training they're supposed to
do better by their patients
Semmelweis was determined to find out
what was going on he noted that one of
the main things that physicians did that
midwives did not do was to conduct
autopsies on these mothers after they
died then they would go back and deliver
babies or examine mothers without
washing their hands just like an auto
mechanic who would finish up on one car
and then move to the next car without
washing his hands to get the grease off
and he didn't see any reason to have to
do this symma wondered if the doctors
were carrying some invisible matter on
their hands which they passed on to
their maternity patients causing them to
die to find out he conducted a test he
decided that he would have the student
positions under his control wash their
hands in a chlorine solution and
suddenly the percentage of maternal
deaths dropped to 1% that's lower than
the midwives
with this demonstration some of us
realized that infectious disease in this
case child bed fever has a single cause
if you eliminate the source of the
infection the disease does not occur but
in 1846 no one had made the connection
between bacteria and infections as a
result Cemil vices idea was ignored it
would take 10 more years before another
scientist would turn his attention to
germs his name Louis Pasteur
Pasteur had lost three of his five
children to typhoid fever which perhaps
explains why he was determined to find
the cause of infectious diseases
it was pastures work on behalf of the
beer and wine industry that put him on
the right track Pasteur was trying to
find out what was spoiling so much of
the country's wine production he
discovered that the spoiled wine was
contaminated by a microorganisms germs
and the germs were causing the wine to
sour but with a simple heat treatment he
showed that the germs could be killed
off and the wine saved the
pasteurization process was born
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so when it came to finding the cause of
infections and contagious disease
Pasteur knew where to look germs he said
cause specific diseases and he proved it
through a series of experiments and
demonstrations that led to his great
discovery germ theory the germ theory
literally marks the beginning of modern
medicine the germ theory has one central
idea that one microorganism causes one
disease in everybody our next great
discovery happened in the 18th century
when smallpox killed an estimated 40
million people around the world doctors
were unable to find the cause or
discover a cure
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but in a small English village talk of
how some locals were immune to smallpox
got the attention of a country doctor
named Edward Jenner it was said that
villagers who worked in the dairy
business were safe from smallpox because
they'd already been infected by cow pox
unrelated but less severe disease that
afflicted cattle cow pox victim suffered
fever and sores on their hands but
little else Jenner studied the
phenomenon and began to wonder if the
pus in the cow pox sores was somehow
responsible for protecting against
smallpox on May 14 1796 during an
outbreak of smallpox he decided to test
his theory Jenner withdrew puss from the
cow pox sores on the hands of a
dairymaid
then he visited another family in the
village he inoculated a healthy
eight-year-old boy with the cow pox
virus confident in the outcome in the
days that followed the boy developed a
slight fever and some cow pox blisters
then recovered
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six weeks later Jenna returned this time
he inoculated the boy with small parts
then waited the moment of success or
failure was at hand
within days Jenner had his answer
the boy was completely healthy resistant
to smallpox vaccinations for smallpox
was revolutionary because it represented
people's attempt to intervene into the
disease process to prevent it up front
this is the first time a man-made
product had been used actively to
prevent disease before it occurred
fifty years after Jenner's discovery
louis pasteur pushed a concept of
vaccination even further developing
vaccines against rabies and humans and
anthrax and sheep and in the 20th
century Jonas Salk and Albert Sabin
independently developed vaccines against
polio and we owe it all to Jenner's
great discovery
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our next great discovery depended on the
contributions of researchers working
independently on the same problem over
many years throughout history scurvy was
a painful disease that inflicted sailors
with hemorrhaging and skin lesions
finally in 1747 a Scottish naval surgeon
named James Lind found a remedy he
discovered that scurvy could be
prevented by including citrus fruits in
a sailor's diet
another disease afflicting sailors was
berry-berry
a degenerative disease that attacks the
nerves heart and digestive system toward
the end of the 19th century a Dutch
physician named Christian Eichmann
traced its cause to diets that included
polished white rice
rather than unpolished brown rice while
both these discoveries indicated a link
between diseases and dietary
deficiencies it wasn't until the work of
British biochemist Frederick Cowell and
Hopkins that the connection became clear
Hopkins suspected that our bodies need
certain nutrients that can only be
acquired by eating certain foods to
prove his point he conducted a series of
experiments he fed mice a synthetic diet
consisting entirely of pure protein fats
carbohydrates and salts the mice became
sick and stopped growing but given a
small amount of milk the mice recovered
Hopkins had discovered what he called
accessory food factors which later came
to be known as vitamins
berry-berry it turned out was caused by
a deficiency in thiamine vitamin b1
which was lost in polished rice but
plentiful in the natural grain and
citrus prevented scurvy because it
contained ascorbic acid vitamin C
Hopkins discovery was a major shift in
our understanding of the importance of
nutrition vitamins are responsible for
so many of our body's normal functions
everything from fighting infection to
regulating metabolism it's hard to
imagine life without them just like our
next great discovery
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world war 1 more than ten million dead
many from the infection of their wounds
after the war were search intensified to
find safe methods of repelling the
bacterial invaders among those on the
case was Scottish physician Alexander
Fleming while studying Staphylococcus
bacteria Fleming noticed something
unusual growing in the culture dish a
mould penicillium notatum he saw that
the bacteria surrounding the mold had
died off which led him to speculate the
mold was producing a substance that was
lethal to the bacteria he named the
substance penicillin for the next
several years
Fleming tried extracting penicillin and
applying it to treat infections but he
was unsuccessful and eventually gave up
Fleming's work however proved invaluable
in 1935 scientists Howard Florey and
Ernst chain at Oxford University came
across a record of Fleming's curious but
incomplete work with penicillin and
decided to investigate this time they
successfully extracted and purified
penicillin and in 1940 they tested it
they injected eight mice with lethal
doses of the bacteria streptococcus then
they injected four of the mice with
penicillin within hours they beheld the
results the four mice not treated with
penicillin were dead but three of the
four that had been given penicillin were
alive from Fleming - Florian chain
the world's first antibiotic was born it
was a miracle drug it cured so many
diseases that had caused so much pain
and suffering strep throat rheumatic
fever scarlet fever syphilis and
gonorrhea it was things that we wouldn't
even think about today should kill you
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our next great discovery came to the
rescue in World War two
it provided soldiers with a drug to
fight dysentery while they fought in the
South Pacific eventually it also led to
a revolution in the chemo therapeutic
treatment of bacterial infection the
scientist who made it all happen was
pathologist Gerhardt doe mark in 1932
doe MOC was studying the potential
medical applications of some new
chemical dyes working with a newly
synthesized chemical dye called pronto
Sol democ injected it into some lab mice
that were infected with streptococci
bacteria the dye attached to the
bacteria just as doma had hoped but the
bacteria survived the dye it seemed
wasn't toxic enough then something
startling happened while the dye didn't
kill the bacteria it did inhibit their
growth the spread of the infection was
stopped the mice recovered
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it's not clear when democ used pronto
salon a human patient but the new drug
achieved fame when it saved the life of
a boy seriously infected with
streptococci the patient's name Franklin
D Roosevelt jr. son of the President of
the United States
from that moment on doe March discovery
was a sensation because pronto soul
contained what was known as a
sulfanilamide molecular structure it was
called a sulfa drug the first of its
kind a synthetic chemical substance that
could cure and prevent bacterial
infection doma had opened the door to a
revolutionary new approach in the
treatment of disease the use of chemo
therapeutic drugs a discovery that would
go on to save tens of thousands of lives
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our next great discovery helps save the
lives of millions worldwide who were
afflicted with diabetes diabetes is a
disease that disrupts the body's
mechanism for processing sugar which can
lead to blindness kidney failure heart
disease even death for centuries
physicians studied diabetes searching in
vain for a cure finally in the late
1800s a breakthrough occurred it was
discovered that the bodies of diabetics
had something in common a group of cells
in the pancreas was always damaged these
cells produced a hormone that controlled
blood sugar that hormone was called
insulin
then in 1920 another breakthrough
Canadian surgeon Frederick Banting and a
graduate student named Charles best were
studying how insulin was produced in the
pancreas of dogs on a hunch
Banting took an extract from the insulin
producing cells of healthy dogs and
injected the extract into other dogs
already afflicted with diabetes the
results were astounding within a few
hours the blood sugar levels of the
diabetic dogs decreased significantly
now Banting and his team set their
sights on finding an animal whose
insulin bore a close resemblance to
human insulin they found a close match
in the insulin taken from cow fetuses
purified it for safe treatment then in
January 1922 conducted the first
clinical trial
Banting administered the insulin to a
fourteen-year-old boy dying of diabetes
and the boy made a dramatic recovery how
important was Banting's discovery why
not ask the estimated 13 million
Americans who rely on insulin to control
their diabetes every day
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cancer the second leading cause of death
in the United States intensive research
into its origins and development has
spawned remarkable scientific
breakthroughs perhaps none more
significant than our next great
discovery to find out about the
discovery I caught up with two Nobel
Prize winning cancer researchers Michael
Bishop and Harold Varmus
at the Memorial Sloan Kettering Cancer
Center in New York City Varmus and
Bishop first joined forces to research
cancer in the 1970s at the time there
were several prevailing theories about
the cause of the disease the malignant
cells complicated it's not just a cell
it can replicate indefinitely it's a
cell it can invade elicit new blood
vessels it has a very complex capability
one theory concerned the Rous sarcoma
virus a virus that caused cancer in
chickens when the virus attacked the
cells of a chicken it inserted its
genetic material into the hosts DNA
according to the theory the viral DNA
later became a cancer-causing agent
a second theory suggested that once the
Rous sarcoma virus inserted its genetic
material into the host cell the
cancer-causing genes didn't activate
themselves but remain dormant until
triggered by outside influences such as
harmful chemicals radiation or even
viral infections these cancer-causing
genes called Anki genes became the focus
of Varmus and bishops research the
fundamental question was does a human
cell does the human genome contains that
either are or are capable of becoming
uncle genes of the sort that are in a
virus tumor causing genes to are causing
genes cancer-causing genes right are
they in there or not so what did you
discover first we started with the
chicken because that's where this virus
came from is their gene and chickens and
then later is their gene and other birds
in mammals and humans related to the
cancer gene of the Rous sarcoma virus so
we did was to make a radioactive
molecule that could be used as a probe
for asking whether the oncogene of Rous
sarcoma virus resembled a normal gene
present in in the chromosomes of a
chicken and the answer was yes it was a
landmark discovery Varmus and Bishop
found that the cancer-causing gene was
already present in the DNA of normal
uninfected chicken cells even more
remarkable they found it in human DNA as
well proof that the seeds of cancer may
already be inside each of us at the
cellular level just waiting to be
activated how can one of our own genes
which we've we've had our lives caused
cancer when cells divide mistakes are
made they are more frequent if the cell
is stressed by cosmic rays cigarette
smoke cigarette smoke a good example it
is important also to recognize that when
cells divide they have to copy three
billion base pairs of DNA and anybody
who's ever tried to type something knows
that it's not easy to do that we have
spellcheck mechanisms that allow
detection of mistakes and repair those
mistakes but still things slip through
when you're doing things
thuja large-scale so why is this a great
discovery that difference between the
gene and the virus and the gene in the
cell exemplifies the fundamental way
people were trying to think about cancer
and we now do think about cancer that
small changes in particular genes and
ourselves can convert cells from
controlled regular growth and other
behavior to the behavior of a malignant
cell and this really was the first
direct illustration of that sort of
thing is modern cancer research a result
of your discovery it's a fundamental
platform on which almost all molecular
approaches to cancer is built and indeed
you know someone now runs a cancer
hospital what's exciting for me at the
moment is seeing how understanding of
cancer at the molecular and genetic
level is influencing the way in which we
treat a lot of our patients why is it
important looking for this kind of gene
is vital in Diagnostics now it's vital
in in prediction of how cancers are
going to behave and above all else it's
vital because it's provided these
targets for truly specific therapy that
we simply didn't have before
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the city of Chicago population about
three million the same number of people
who are dying each year from AIDS
one of the worst epidemics in modern
history
the first clues about the disease
emerged in the early 1980s researchers
in the United States reported that a
rising number of patients were dying
from rare infections and cancers blood
samples revealed that the patients had
extremely low levels of cd4 T
lymphocytes white blood cells vital to
the body's immune system in 1982 the
Centers for Disease Control and
Prevention gave the disease a name AIDS
acquired immune deficiency syndrome two
researchers took up the case Luc
montagnier
at the institut pasteur in Paris and
Robert Gallo at the National Cancer
Institute outside Washington DC both
share credit for the breakthrough
discovery that eventually uncovered the
cause of AIDS HIV human immunodeficiency
virus what is different about human
immunodeficiency virus from another
virus like like the flu or something
firstly I the virus doesn't give
evidence of disease for years let's take
an average seven years seven years
second problem that was rather unique by
the time a person presented themselves
with AIDS and said you know I'm sick I'm
hearing to go in the hospital they had a
myriad of other infections what was the
cause how do you demonstrate which one
of these is the cause of the disease in
most cases a virus exists for one
purpose to infect a host cell and
reproduce typically it attaches itself
to the host then releases its genetic
information into the cell
this enables the virus to take over the
cells normal functions redirecting them
to produce new virus particles these
particles are then released to attack
more cells HIV is not a conventional
virus it belongs to the family of
viruses are the category of viruses that
scientists call retroviruses how our
retrovirus is different just like the
virus classes that include polio or
virus classes that clewd influenza
retroviruses are another type of virus
what's unique about a retrovirus is that
and what we might say is a cynic wanna
know of a definition of a retrovirus is
its genetic information in the form of
RNA is converted into DNA but it's what
happens to DNA that gives us our problem
is that the DNA gets incorporated into
our genes the DNA of the virus becomes
part of us as the T helper cells
reproduce they're reproducing with the
virus exactly the retrovirus DNA is
actually exactly forever before I never
get over it you'll have cells harboring
the genetic information for the virus
sometimes making a virus others silent
quiet perhaps hidden but only later to
pop out and reproduce virus again that
means very rapidly upon infection we're
establishing an infection that's likely
to be lifelong that's what that's the
crux of the issue for me a cure for HIV
remains elusive but the discovery that
HIV is a retrovirus and that HIV causes
AIDS has led to breakthroughs in the
fight against the disease and beyond
what has changed in medicine since the
discovery of retroviruses or more
specifically the discovery of this virus
aids has been the lead ship in showing
that antiviral drug therapy is possible
in general it was thought because
viruses usurp the cell our cells for how
they reproduce themselves that would be
nearly impossible to target them
effectively without poisoning a person
badly you're saying that nobody was
investing and if I may
English biotics AIDS has opened the door
to antiviral research and the
pharmaceutical companies and
universities broadly across the world
AIDS has also had positive spin-offs
sociologically I witnessed firsthand a
difference between developing and
developed nations you can't just drop
the drugs on the beach and run home it
requires training on how to use the
drugs and we have that relationship with
several African countries now so this is
an irony that this horrible disease is
actually bringing people together I
think so thanks to the discoveries that
we've just seen the world has changed
from germ theory to uncovering the
origins of cancer these breakthroughs
have altered the course of history
saving countless lives and pushing the
boundaries of our medical knowledge to
where we are today ready for the next
breakthrough the next great discovery