Diseases in ICPP

Question 1

Hereditary spherocytosis

Answer 1

Lattic structure of cytoskeleton more open as spectrum is depleted by half
Erythrocytes are circles instead of biconcave discs, don’t fit through capillaries and Hb leaves = lifelong anaemia

Question 2

Hereditary elliptocytosis

Answer 2

Spectrin is rugby shaped

Lattice weak and cells lysis - fragile = life long anaemia

Question 3

Devic’s disease

Answer 3

Breakdown of myelin sheath affects conduction of AP in optic and spinal cord nerves

Question 4

Charcot Marie Tooth disease

Answer 4

Loss of muscle tissue and touch sensation due to conduction of AP being affected

Question 5

Myasthenia gravis

Answer 5

Autoimmune disease targeting nAchr
Weakness that increases w exercise
Normal neuromuscular junction transmission but end plate potential fails to reach threshold

Question 6

Diagnosing myasthenia gravis

Answer 6

Edrophonium test = anti-AchE given by injection, Ach builds up and allows contraction - facial weakness will rapidly be relieved by this test

Question 7

Organophosphate poisoning

Answer 7

AchE inhibitor

Forms covalent and irreversible bond to enzyme so Ach builds up and constant AP

Question 8

Cholera toxin

Answer 8

CTx prevents termination of signalling by Gs preferring GPCRs = activation of downstream pathways
Takes away GTPases ability = no offswitch

Question 9

Pertussis toxin

Answer 9

Whooping cough
PTx covalently modifies a1 subunits so that they don’t GDP/GTP
Uncouples Gi preferring GPCRs from mediating signal transduction events

Question 10

Asthma

Answer 10

Caused by obstruction to airflow and bronchospasm