Kill or Cure
Medicine in the West: the rise of
science
Aims
• To introduce the idea and impact of laboratory
medicine.
• To see how the laboratory provided the
context for the development of bacteriology.
• To think about the role played by bacteriology
in the shift from ‘dirt to germs’ in theories of
disease causation.
• To explore the history of genetics and its
effects on modern medicine.
Part one
• The rise of laboratory medicine
Introduction to laboratory medicine
• From the latter half of the 18th C western medicine witnessed
fundamental changes. These were evident in medical theory: the
ways in which the workings of the body in health and disease were
understood.
• The spaces in which medical knowledge was developed and applied
also underwent transformation. Laboratory medicine sought to
explain the structure of the body at the cellular level and to
describe its function as a complex series of dynamic processes.
• The laboratory usurped the hospital as the locus of research, and
the laboratory scientist claimed a greater authority than the clinical
practitioner. The diagnosis of particular infectious diseases now
relied on tests on tissue samples performed at the lab bench, not
simply on the subjective analysis of patterns of symptoms.
• These changes that occurred were complex and interrelated. They
proceeded at various rates in different parts of the western world.
Learning from the laboratory
The rising sciences of life:
• Cell biology and pathology
( bacteriology and
parasitology)
• Physiological chemistry (
experimental physiology)
• Pharmacology
Nicholas Jewson, ‘The
disappearance of the sickman from medical
cosmology, 1770-1870’,
Sociology, (1976) 10; 22544.
Techniques:
• Microscopy
• Histology
• Vivisection
Tools:
• Microscope
• Sphygmograph
• Spirometer
• Thermometer
• Scales, etc.
c. 1850s, esp. Germany
Part two
• The ‘discovery’ of bacteria
Bacteriology
• Bacteriology is the study of bacteria.
• Roy Porter argues that the development of bacteriology in the
latter part of the 19th C brought one of medicine’s few true
revolutions.
• The general thinking behind bacteriology (that diseases is due
to tiny invasive beings) was not new (theories of contagion
maintained that disease entities were passed from the
infected party to others).
• However it was only in the 19th C that the rise of pathoanatomy led to the belief that specific parasites and bacteria
would be responsible for particular diseases.
Pasteur and Koch
Louis Pasteur 1822-1895, a
French chemist and biologist
who proved the germ theory of
disease and invented the
process of pasteurisation.
Robert Koch 1843-1910, a
German physician and
pioneering microbiologist. The
founder of modern bacteriology.
‘Magic bullets’
• A magic bullet is a perfect drug to cure a disease with no
danger of side effects. The term magic bullet was first used in
this sense by the German physician and scientist Paul Ehrlich
who received the Nobel Prize in Physiology or Medicine in
1908.
• Initially, Ehrlich invoked the notion of a magic bullet in
characterizing antibodies. He then reused the concept of a
magic bullet to apply to a chemical that binds to and
specifically kills microbes or tumor cells.
• Ehrlich's best known magic bullet was arsphenamine
(Salvarsan, or compound 606), the first effective treatment for
syphilis. At a meeting in 1910, Ehrlich and his colleagues
announced the remarkable effects of their treatment of
syphilis with this magic bullet.
Koch’s postulates
• The organism suspected of causing a particular
disease could be discovered in every instance of the
disease.
• When extracted from the body, the germ could be
grown in the laboratory and maintained for several
generations.
• When this culture was injected into animals, it
should induce the same disease observed in the
original source.
• The organism could then be retrieved from the
experimental animal and cultured again.
Part three
• From ‘dirt’ to ‘germs’
Miasma
Malaria, a disease
transmitted by
mosquitoes and still
widespread in many
tropical areas of the
world, was once
endemic in temperate
latitudes.
La Mal’aria, by A. Hebert, which hangs in the Musée d’Orsay, Paris, shows a
group of people in the Pontine marshes as a result of malaria. Prior to the late
19th C it was assumed that the disease emanated directly from evil-smelling
marshes – hence the name ‘mal’aria’, literally meaning ‘bad air’.
Cholera
John Snow, Broad Street Pump,
1855
John Snow (1813-1858) observed a correlation between the disease and where it
spread, and with the source of public water. In 1855, he published On the Mode of
Communication of Cholera. This treatise was a milestone in public health as it
correctly identified the fecal-oral route of human infection and offered powerful
arguments for the germ theory.
Bacteriology and the ‘grand
research institutes’
The Pasteur Institute, Paris, 1888. The institute was built in Paris in 1888 both to
honour the work of Louis Pasteur and to provide a base for his further research.
Bacteriology and disease control
• Firstly the discovery of the
identity of disease-causing
pathogens gave rise to hopes
that particular complaints
could be prevented and
treated by new vaccine
therapies.
Louis Pasteur and
the rabies cure, 1885
• Secondly bacteriology enabled
disease control through the
isolation of infected persons.
While isolation was not new,
bacteriological tests gave
authorities accurate knowledge of
the identity and presence of
disease.
London Open Air Sanatorium for Tuberculosis, c.1907
Sanitary reform and public health
Max von Pettenkofer (1818-1901). Pettenkofer’s name is
most familiar in connection with his work in practical
hygiene, as an apostle of good water, fresh air and proper
sewage disposal. His attention was drawn to this subject by
the unhealthy condition in Munich in the 19th century.
Part four
• From ‘germs’ to ‘genes’
Founding fathers
Gregor Johann Mendel (1822-1884). A scientist and
Augustinian friar. Published ‘Experiments in Plant
Hybridization’ in1865. The ‘founder’ of the modern science
of genetics. He discovered the basic principles of heredity
through experiments breeding plants. He showed that
some traits such as height or flower color do not appear
blended in their offspring. His work also demonstrated that
variations in traits were caused by variations in inheritable
factors.
Charles Robert Darwin (1809-1882). An English naturalist and
geologist, best known for his contributions to evolutionary
theory. Published the Origin of Species in 1859. The rise of
Darwinism also led to the advancement of eugenics. Darwin had
concluded his explanations of evolution by arguing that the
greatest step humans could make in their own history would
occur when they realized that they were not completely guided
by instinct. Rather, humans, through selective reproduction, had
the ability to control their own future evolution.
Mendel’s heirs
• The word gene was first used in 1909 by the
Danish botanist Wilhelm Johannsen to describe
the Mendelian units of heredity.
• The American geneticist Thomas Hunt Morgan
studied the segregation of mutations in the fruit
fly. Morgan used mutations to move beyond the
laws that managed heredity to examine the
specific mechanisms—the genes themselves—
that carry out the process. By finding and
breeding hundreds of visible mutants, including
those with variations in body color and wing
shape, he created chromosome maps that
showed where on each of the fruit fly’s 4
chromosomes certain genes lay.
• The fact that genetic linkage corresponded to
physical locations on chromosomes was shown
later, in 1929, by Barbara McClintock, in her
cytogenetic studies on maize.
Illustration from Morgan’s,
A Critique of the Theory of
Evolution (1916)
DNA
One of Watson and Crick’s
original models for the
structure of DNA.
James Watson and Francis Crick, 1959
• In the 1950s, at the Cavendish Laboratories in Cambridge, England, scientists developed
X-ray crystallography, a technology that made it possible to interpret the threedimensional structure of a crystallized molecule.
• It allowed Maurice Wilkins and Rosalind Franklin to take "snapshots" of DNA that were
used in 1953 by James Watson and Francis Crick to build their now-famous model: DNA
was shaped like a spiral staircase, or double helix.
• Their discovery of the actual physical structure of DNA finally created a consensus among
geneticists that genes were real.
The age of molecular genetics
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1970 - Arber and Smith - First restriction enzyme, Hind II, is isolated
1970 - Baltimore and Temin - Discovery of reverse transcriptase
1972 - Berg - First recombinant DNA molecule is constructed
1973 - Boyer and Cohen - First functional recombinant E. coli cell produced
1977 - Sanger and Gilbert - DNA sequencing techniques are described
1977 - Sharp and Roberts - Introns discovered
1978 - Botstein - RFLPs launch the era of molecular mapping of linkage groups
1980 - Sanger Group - First genome is sequenced, the bacteriophage ΦX174 of E. coli
1983 - Mullis - PCR technique is discovered
1986 - Hood, Smith, Hunkapiller and Hunkapiller - First automated DNA sequencer
1990 - US Government - Human Genome Project launched
1995 - Celera - First bacterial genome (H. influenza) is sequenced
1996 - Yeast Genome Consortium/ First eukaryotic genome (yeast) sequenced
2000 - Arabidopsis Genome Initiative - First flowering plant genome (Arabidopsis
thaliana) is sequenced
2001 - The human genome sequence is published
The new eugenics?
• Medical genetics
encompasses a wide
range of health
concerns, from
genetic screening and
counseling to fetal
gene manipulation
and the treatment of
adults suffering from
hereditary disorders.
• Applications of the
Human Genome
Project are often
referred to as “Brave
New World” genetics
or the “new eugenics”.
Conclusions
• The advent of bacteriology was transformative in
understanding of diseases.
• However the extent to which bacteriological science led to the
decline in epidemic disease is harder to assess.
• New germ practices were used alongside old sanitary reforms.
• The transformation of genetic medicine from a marginal field
in the 1950’s to a core activity of biomedicine was a major
development in modern science.
• The past two decades we have witnessed an increase and
more intense focus on the genetic and biological basis for
disease.
• However at least the 18th C scientists, doctors and patients
had tried to establish links between heredity and disease.