Etiology Chapter 1

John Snow

(1813-1858) -Determined the mode of cholera transmission in London

Florence Nightingale

(1820-1910)- Nurse who implimented cleanliness and other antiseptic techniques during the Crimean War -Went on to found the Nightingale School for Nurses

Prokaryotes

-Bacteria and Archaea -Unicellular and lack nuclei -Reproduces asexually (make clones)

Biochemistry

-Field sparked by Buchner -The study of metabolism

Buchner's Experiments

-Showed that fermentation does not require living cells -Demonstrated the presence of enzymes

The Classical Golden Age of Microbiology

1854-1914

Miasma (pollution)

Considered a poisonous vapor that caused cholera and other diseases

Disease

Disrupting homoestasis

Redi's Experiment

Found that if flies were prevented from landing on meat, it did not produce maggots

Soho, London

In 1854 it was the hot spot for Cholera (Broad Street)

In 1859

Louis Pasteur discredited the idea of spontaneous generation

Postulate 3

Microorganisms from the pure culture are inoculated into a healthy, susceptible animal. The disease is reproduced.

Epidemic

More than the expected number of cases at that particular time

Algae

Multicellular photosynthetic organisms

Molds

Typically multicellular organisms that grow as long filaments

Bioremediation

Use of living bacteria, fungi, and algae to detoxifying polluted enviroments

Fungal Pathogens

ex. Cryptococcus neoformans -AIDS patient

Bacterial Pathogens

ex. Escherichia coli or Entamoeba coli - 1-3 micrometer

Linus Pauling

proposed in 1965 that gene sequences could provide a means of understanding evolutionary relationships and processes, establishing taxonomic categories that more closely reflect these relationships, and identifying the existence of microbes that have never been cultured

Antoni van Leeuwenkhoek

-Began making and using simple microscope -Often made a new microscope for each specimen -Examined water and visualized tiny animals, fungi, algae, and single-celled protozoa: "animalcules"

Problems with the postulates

-Can be infected and not show symptoms (have pathogen, but no disease) -Mutations -Ethics -Cause could be 2+ organisms

Ignaz Semmelweis

-Determined the source of blood poisoning of women in childbirth (Puerperal Fever) -Handwashing

Joseph Lister

-Developed the practice of antisepsis chemical disinfection of external living surfaces -Spraying and surgical incisions wounds with phenol

Robert Koch

-Formalized standards to identify germs with infectious diseases -Postulates became the standard for linking a specific organism to a specific disease

Eukaryotes

-Fungi, Protozoa, Multicellular organisms -Have a nucleus -Membrane-bound organelles

Immunology

-Jenner began the field of immunology -The study of the body's specific defenses against pathogens

Louis Pasteur

-Proposes that germs cause infectious disease -Pasteurization -Proposed germ theory in 1862 -Experiment involved swan neck flask

Pathogen

A biological agent that causes disease or illness in its host

Gene Therapy

A process that involves inserting a missing gene or repairing a defective one in human cells

Taxonomic system

A system for naming plants and animals and grouping similar organisms together

Yeast

Are unicellular and typically oval to round

Cholera

Bacteria (Vibro cholerae)

Redi's Experiment

Found that if flies were prevented from landing on meat, it did not produce maggots -Scientist began to doubt Aristotle's theory

Gram-negative cell

Generally, a prokaryotic cell having a wall composed of a thin layer of wall material, an external membrane, and a periplasmic space between; appears pink after the Gram staining procedures

Germ Theory of Disease

In 1857 that microorganisms are also responsible for disease

Spontaneous Generation

In the 1600's many people thought life generated spontaneously from putrid and decaying materials

Variolation

Involved exposing individuals to dried smallpox specimens

Recombinant DNA Technology

Is DNA composed of genes from more than one organism

Gram-positive cell

Prokaryotic cell having a thick wall; in bacteria, composed of a thick layer of peptidoglycan containing teichoic acids; Gram-positive cells retain the cyrstal violet dye used in the Gram staining procedure, appearing purple

Metabolism

Refers to the sum of all chemical reactions within an organism

Pure Culture

Robert Koch- by adding gelatin to his broth RK was able to grow bacterial colonies in a Petri dish

Infection Control and Epidemiology

Snow's study was the foundation for two branches of microbiology

Needham's Experiments

Stated that there must be a "life force" because he heatedthe vials to kill everything, but yet they were still cloudy

Ehrlich's Experiments

Suggested that chemicals could be used to kill microorganisms deferentially

Gram Stain

Technique for staining microbial samples by applying a series of dyes that leave some microbes purple and other pink (Developed by Christian Gram in 1884)

Postulate 4

The identical microorganisms are isolated and recultivated from the tissue specimens of the experimental animal

Postulate 2

The microorganism are isolated from the tissues of a dead animal, and a pure culture is prepared

Postulate 1

The same microorganism are present in every case of the disease

Etiology

The study of causation or origination of a disease or medical condition

Genome

The total genetic information of an organism

Protozoan Pathogens

ex. Leishmania -proto "first" & zoan "animal" -single cell organism

Multicellular Pathogens

ex. Liver fluke, ascaris and hookworms

Viral Pathogens

ex. West Nile Virus -40-60 nanometers

Molecular Biology

Combines aspects of biochemistry, cell biology, and genetics to explain cell function at the molecular level

Spallanzani's Experiment

Contradicted Needham's experiments. His flask stayed clear after being heated for an hour...he concluded 3 things -Needham failed to heat his vials sufficiently -Microorganisms exist in the air -Spontaneous generation is false

Edward Jenner

Developed vaccination, inoculating individuals with cowpox

Carl Woese

Discovered that significant differents in nucleic acid sequence among organisms clearly reveal the cells belong to one of three major groups: bacteria, archaea or eukaryotes

Chemotherapy

Ehrlich's discoveries began the branch of medical microbiology