Block 1 Diseases

Question 1

Amyloidosis

Answer 1

lysed amyloid plaques aggregate into beta-pleated sheets

Question 2

Alzheimer’s disease

Answer 2

neurotoxic accumulation of amyloid plaques

also neurofibrillary tangles from Tau proteins

Question 3

Prion diseases

Answer 3

including: Creutzfeldt-Jakob disease, scrapie, and bovine spongiform encephalopathy (mad cow)
infectious misfolded prion proteins copy themselves

Question 4

Hemophilia A (classic hemophelia)

Answer 4

absence or deficiency in Factor VIII

Question 5

Hemophilia B (Christmas disease)

Answer 5

absence or deficiency in Factor IX

Question 6

Von Willebrand disease

Answer 6

deficiency/defect in von Willebrand factor, a protein required for platelet adhesion
(3 types)
most common coagulopathy

Question 7

Hemophilia C

Answer 7

absence or deficiency in Factor XI

Question 8

Bernard-Soulier Syndrome

Answer 8

deficiency of GP Ib (receptor for von Willebrand factor)
characterized by giant platelets
inc. bleed time

Question 9

Glasmann’s Thrombastenia

Answer 9

lacks functional GP IIb/IIIa

platelets cannot bind to fibrinogen

Question 10

Sickle cell anemia (Hb S disease)

Answer 10

substritution of Val for Glu on beta-chain of Hb subunit
causes hemolytic anemia
heterozygous form has malarial advantage (RBC dies quickly)

Question 11

Hb C disease

Answer 11

substitution of Lys for Glu on beta-chain of Hb subunit

causes hemolytic anemia

Question 12

Hb SC disease

Answer 12

one beta-chain is Hb C and the other is Hb S

Question 13

Methemoglobinopathy (Hb M disease)

Answer 13

Fe (on alpha or beta-chain) oxidized to Fe3+ in heme group, making MetHb
Hb binds to H2O instead of O2
causes chocolate cyanosis
treated with methylene blue
binds to CN-, prevent poisoning with amyl nitrate

Question 14

Thalassemia

Answer 14

= category of disorders of unbalanced Hb chain synthesis

Question 15

Alpha-thalassemia

Answer 15

absent or decreased alpha-chain synthesis of Hb
1 defective- no symptoms
2 defective- mild symptoms
3 defective- severe hemolytic anemia (Hb Bart’s or Hb H only in newborns)
4 defective- Hb Bart’s or hydropsfetalis, leads to fetal death

Question 16

Beta-thalassemia

Answer 16

absent or decreased beta-chain synthesis
minor- not threatening
major- normal at birth, severe anemia in infancy, die in puberty
leads to hemosiderosis (iron overload)

Question 17

Emphysema (genetic)

Answer 17

causes damage to alveolar sacs
Missense mutation in alpha-1-antiproteinase (alpha-1 AT)
smoking oxidixes methionine in alpha-1 AT, cannot prevent neutrophil elastase from eating away at alveolar sacs

Question 18

Ehlers-Danlos Syndrome

Answer 18

defect in synthesis of collagen for skin (I and III) and fibrillar collagens (IV)
stretchy, thin, transparent skin and loose joints

Question 19

Osteogenesis imperfecta

Answer 19

brittle bone syndrome
substitutions of Gly in Type I collagen
characteristic blue sclera
OI tarda= decreased alpha-1 and alpha-2 chains
OI congenita= substitution of bulky amino acids for Gly in alpha-1 or alpha-2 chains, no tight packing

Question 20

Marfan’s Syndrome

Answer 20

mutation in fibrillin-1
tall, loose-jointed, heart murmurs
eye dislocation

Question 21

Myocardial infarction, identifying

Answer 21

determined by high levels of creatine kinase 2 (CK2) within 24 hours

Question 22

Cystic fibrosis

Answer 22

defect in chloride membrane transport by epithelial cells
retention of NaCl by cells in lungs, which pull water from airway
leads to extra salty sweat and dry, thick mucous

Question 23

Leber hereditary optic neuropathy (LHON)

Answer 23

blindness from mutation in complex I of electron transport chain
impairs NADH utilization for CoQ

Question 24

Chronic Progressive External Opthalmoplegia (CPEO)

Answer 24

progressive paralysis of extraocular muscles from deletions of mtDNA
Kearns-Sayre Syndrome= most severe case