Lecture 3 Notes Flashcards
Pathology
The study of disease
Etiology
The study of the cause of the a disease
Pathogensis
The development of a disease
Infection
Colonization of the body by pathogens
Disease
An abnormal state in which the body is not functioning normally
Transient microbiota
May be present for days, weeks or months
Normal microbiota
Permanently colonized the host
Symbiosis
Is the relationship between normal microbiota and the host
- both benefit (obligatory)
Lysozyme
An enzyme that catalyzes the destruction of the cell walls of certain bacteria
Propionibacterium
A bacterium that metabolizes carbohydrates
Staphylococcus
A bacterium of a genus that includes many pathogenic kinds that cause pus formation
Micrococcus
A spherical bacterium that is typically found on dead or decaying organic matter
Diphtheroid
Any bacterium of a genus that includes the diphtheria bacillus
- does not cause disease
Lactobacillus
A rod-shaped bacterium that produces lactic acid from the fermentation of carbohydrates
Bacteroides
Bacterium that is resistant to penicillin
Klebsiella
A bacterium that causes respiratory, urinary and wound infection
Microbial antagonism
Is a competition between microbes
What are 6 ways normal microbia protect the host?
- Competing for nutrients
- Producing substances harmful to invading microbes
- Affecting pH and available O2
- Occupying niches that pathogens might occupy
- Produces acid
- Produces bacteriocins
Bacteriocins
Chemicals produced by certain bacteria that suppresses other bacterial cell walls
Probiotics
Live microbes applied to or ingested into the body, intended to exert a beneficial effect
Nisin
A bacteriocin used a food preservatives
- eg) preserved milk in developing countries to prevent growth of bacteria
Bacteria
Unicellular organisms which a cell has no nucleus
- Eubacteria
Protozoa
Unicellular organisms which a cell a nucleus
- Eucaryota
What organisms are hard to develop a vaccine against?
Protozoa’s
Virus
Obligately intracellular parasite that cannot reproduce by itself
Prions
Proteins causing slow degenerative disease in animals and humans
What was the story of Kuru? (3)
- Brains were infected
- Eaten by other people
- This was a form of showing respect for those who had the disease
What was the % of death in Africa for: infections, nutrition, other, injuries, cardiovascular, cancer and respiratory? (7)
- Infection = 61%
- Nutrition = 10%
- Other = 7%
- Injuries = 7%
- Cardiovascular = 8%
- Cancer = 5%
- Respiratory = 2%
What was the % of death in America for: infections, nutrition, other, injuries, cardiovascular, cancer and respiratory? (7)
- Infection = 11%
- Nutrition = 4%
- Other = 18%
- Injuries = 10%
- Cardiovascular = 34%
- Cancer = 18%
- Respiratory = 5%
What is a big source of disease?
Bacteria
What percent of children have an infection in the first 10 years of their lives?
95%
Orthomyxovirus
Flu virus
What are Koch’s postulates? (4)
- The same pathogens must be present in every case of the disease
- The pathogens must be isolated from the diseased host and grown in pure culture
- The pathogen from the pure culture must cause the disease when it is inoculated into a healthy, susceptible laboratory animals
- The pathogens must be isolated from the inoculated animal and must be shown to be the original organism
What are the steps for Koch’s postulates? (7)
1) Microorganisms are isolated from a diseased or dead animal
2a) The microorganisms are grown in pure culture
2b) The microorganisms are identified
3) The microorganisms are injected into a healthy laboratory animal
4) Disease is reproduced in a laboratory animal
5a) The microorganisms are isolated from this animal and grown in pure culture
5b) Microorganisms are identified
What did they discover in Koch’s postulates?
That the microorganisms from the diseased host caused the same disease in the lab hosts
What is Koch’s postulates used for?
To prove the cause of an infectious disease
