Case Unit 1 - Cholera and Ebola Flashcards
What is qualitative research?
Addressing questions about thoughts, opinion and behaviour
Generates non-numerical data
What is quantitative research?
Testing a hypothesis through measurement/data collection and statistical analysis
Can be observational or experimental
Why is statistics important?
Quantifies the confidence that your results can be applied to the whole population
What are Koch’s Postulates?
- Organism must be regularly associated with the disease
- Organism must be isolated and grown in culture
- Disease must be reproduced when culture introduced to healthy host
- Same organism must be re-isolated
What is a paradigm shift according to Kuhn?
A fundamental change in the basic concepts and experimental practices of a scientific discipline
What is PCR used for?
Creating many copies of a DNA sample
What ‘ingredients’ does a PCR reaction need?
Target DNA
Primers
DNA nucleotide bases
Taq Polymerase
Describe the PCR process
- Sample and primers mixed together
- Heated to 96 degrees to denature
- Cooled to 60 degrees allowing primers to anneal
- Heated to 72 degrees, DNA polymerase and nucleotides synthesise new DNA strand
- Repeat cycle approx. 30 times
What is qPCR used for?
Quantifying the amount of a specific DNA sequence or expression levels of specific mRNAs
How is the quantity of DNA measured?
Using fluorescent markers e.g. SYBR green
What could you use as a control?
Take DNA and do a separate PCR reaction with primers for a gene whose expression isn’t believed to change
Often GAPDH
Why can’t we compare the control gene to the test gene?
Different sets of primers
May not be equally efficient
What do we measure from qPCR?
Change (delta) in cycle number (ct)
Ct - large upstroke where fluorescence starts
Difference of 1 is double
Compare changes in signal - 2^-detladeltaCt
deltaCt = 1 and deltaCt=4, 2^3 = 8 fold increase
