BIO220 Lecture 7

Question 1

How is malaria spread?

Answer 1

Mosquitos

Question 2

Symptoms of malaria

Answer 2

fever, chills

Anemia (loss of RBC)

Question 3

Methods used to control malaria

Answer 3

1. Drugs in humans
2. Kill vector (mosquito)
3. Decrease contact b/t human and vector

Question 4

Malaria is caused by…

Answer 4

plasmodium

Question 5

What part of the body does plasmodium affect?

Answer 5

Liver -> gametocytes

Question 6

What drug was used to treat malaria in humans?

Answer 6

Quinine sulphate tablets

Used to make tonic (+sugar water)

Question 7

What happened to human drug treatment of malaria?

Answer 7

Resistance spread

Question 8

What are 2 ways to kill mosquitos?

Answer 8

1. Larval stage: remove water

2. Adult stage: pesticides

Question 9

Why is removing water good at combating mosquitoes?

Answer 9

Larval stage feed underwater

No water = no food

Question 10

Why is there treatment of mosquitoes in Toronto as well?

Answer 10

West Nile Disease

Question 11

What happened to pesticide treatment of mosquitoes?

Answer 11

During spraying (1968 - 1990), resistant alleles increased.
When spraying was stopped, resistant alleles also decreased.
Implications:
Some cost to the resistant allele

Question 12

What causes tuberculosis?

Answer 12

Bacteria

Question 13

What type of disease is tuberculosis?

Answer 13

Common, deadly

Question 14

Where does tuberculosis affect?

Answer 14

The lungs

Question 15

What affect did antibiotics have on tuberculosis new & relapsed cases?

Answer 15

21. 5% of relapsed patients became resistant to antibiotics (take it for longer)
22. 2% of new patients became resistant to antibiotics

Question 16

Resistance is closely correlated with…

Answer 16

drug use

Question 17

How fast does resistance happen?

Answer 17

Very fast! 1-5 years.

Question 18

What happened when Iceland decreased use of penicillin?

Answer 18

Resistant strains declined

Question 19

How does the use of antibiotics select for the resistant phenotype?

Answer 19

1. Separate resistant from non-resistant, and favour resistant
2. Mutation of non-resistant types to resistant types

Question 20

How are plasmids with resistant genes be transferred between unrelated bacteria?

Answer 20

Horizontal gene transfer

Conjugation between bacteria.

Question 21

Consequence of not using the word “evolution” in biomedical journals regarding antibiotic resistance

Answer 21

Public press also avoid use of the word -> less public awareness of the issue

Question 22

How is HIV transmitted?

Answer 22

homosexual sex

sex trades

Question 23

Which country is has the highest occurrence of HIV?

Answer 23

Africa

Question 24

How to decrease HIV?

Answer 24

Use condoms

Question 25

Why did the invention of a drug cause an increase in new HIV diagnosis?

Answer 25

People thought of it as a not-serious issue, and stopped being careful with safe sex

Question 26

What drug was used to treat HIV?

Answer 26

AZT

Question 27

How did AZT work?

Answer 27

Azide group replaces OH to prevent joining of next nucleotide during reverse transcriptase

Question 28

Has there been resistance to AZT?

Answer 28

Yes; altered biding site that detects and avoid picking AZT Frequency of resistant type increases as duration of drug use increases (happens independently in each patient)

Question 29

What does the azide group look like?

Answer 29

N3 instead of OH

Question 30

Why does HIV evolve so fast?

Answer 30

1. High mutation rate 2. Short generation time 3. Giant population

Question 31

Fast generation time =

Answer 31

Fast evolution

Question 32

How to get treat HIV given that the virus becomes resistant quickly?

Answer 32

HAART: highly active antiretroviral therapy | = Use a cocktail of different drugs

Question 33

HAART

Answer 33

Highly Active Anti-Retroviral Therapy

Question 34

What happened as a result of HAART?

Answer 34

Deaths from HIV went down

Question 35

Which strain of HIV is the one that makes us more sick?

Answer 35

HIV-1 (not HIV-2)

Question 36

What is the HIV-like virus found in monkeys?

Answer 36

SIV

Question 37

How was HIV transmitted to humans?

Answer 37

From chimps (SIV): 1. Keep them as pets 2. Eat them