A

Question 1

GLYCOLYSIS CLINICAL APPLICATION

Answer 1

Glycolysis rate up to 200x greater in cancer;
PET scan after intake of FDG (radioactive hexokinase substrate) used to detect cancer

Question 2

Low Protein intake, sufficient calorie intake.

Answer 2

KWASHIORKOR

Question 3

Energy deficiency malnutrition

Answer 3

MARASMUS

Question 4

Not enough fibre VS enough fibre.
Where is it found

Answer 4

Constipation, bowel cancer VS cholesterol reduction, reduced risk of diabetes
Cereal foods, bread, beans, fruit and veg

Question 5

vit A deficiency

Answer 5

Xerophthalmia: various eye problems.

Question 6

Vit D deficiency

Answer 6

Rickets, Poor bone development (bone deformities, classically bow legs)

Question 7

Vit E deficiency

Answer 7

Neurological abnormalities (vision, motor effects)

Question 8

Vit K deficiency

Answer 8

Defective blood clotting (VKDB(leeding))

Question 9

B1 (Thiamin) deficiency

Answer 9

Beriberi- neurological problems
(Used in link reaction)

Question 10

B12 deficiency

and Causes

Answer 10

Macrocytic anaemia
Dietary deficiency,
Pernicious anaemia ( lack intrinsic factor, replaces haptocorrin)
Diseased ileum (crohns etc.)
Chemical inactivation eg frequent anaesthetic gas
Parasite
Chelation of intrinsic factor by drugs

Question 11

Fructokinase missing

Answer 11

Essential fructosuria, fructose in urine, no clinical signs

Question 12

Aldolase missing

Answer 12

Fructose intolerance, f1p accumulates in liver, leading to liver damage, managed by removing fructose and sucrose from diet

Question 13

G6PDH deficiency

Answer 13

Can’t go through pentose phosphate pathway, this stops replenishment of NADPH, an important deoxidant. Leads to Heinz bodies and other oxidative damage. Because GSH (glutathione) can be replenished.

Question 14

Deficiency in phenylalanine hydroxylase

Answer 14

PKU (phenylketonuria),
Autosomal recessive genetic, accumulation of phenylalanine in tissue, plasma and urine. Phenylketones built up (phenylacetate and phenyllactate). Gives musty smell in sweat and urine. Has negative effect on brain leading to developmental problems and seizures.

Question 15

Cystathione beta-synthase deficiency

Answer 15

Homocystinuria, problem breaking down methionine, buildup of homocysteine, an intermediate, can be found in urine. Leads to connective tissue and neurological problems. Low methionine diet required, eg avoid milk, eggs, fish, cheese, meat.

Question 16

Vit b6

Answer 16

Makes amino transferase cofactor

Question 17

Galactosaemia

Answer 17

Deficiency of uridyl transferase or galactokinase
Leads to much higher concentrations of galactose or both galactose and galactose phosphate. Leads to oxidative stress as leads to other metabolic pathways such as to Galactitol. Causes cataracts in eyes, oxidation of thiolgroups.

Question 18

Formation of atherosclerotic plaque

Answer 18

LDL have long half life, this makes them more susceptible to oxidative damage. Oxidative damage causes them to be engulfed by foam cells, a type of macrophage. This leads to formation of a fatty streakbuildup in intima of vessels. This atherosclerosis can rupture, causing thrombosis in arteries. Leading to strokes or myocardial infarction.

Question 19

What is ideal total cholesterol
What is ideal non hdl cholesterol
What is ideal ldl cholesterol
Ideal hdl cholesterol
Cholesterol: HDL-C ratio
Triglycerides

Answer 19

=< 5 mmol
=< 4 mmol
=< 3 mmol
> 1 mmol men > 1.2 mmol women
Ratio above 6 high risk, lower the better
<2mmol in fasted sample

Question 20

How do statins work

Answer 20

They inhibit HMG-COA reductase, stopping formation of mevalonate, which later forms cholesterol.

Question 21

Myasthenia Gravis

Answer 21

Autoimmune disease
Antibodies block act receptors
Invaginations reduced
Ptosis- drooping eyelid

Question 22

Muscle atrophy mechanism

Answer 22

DISUSE- bed rest, sedentary behaviour, age, etc
SURGERY- denervation of muscle
DISEASE- muscular dystrophies

Question 23

Duchene muscular dystrophy

Answer 23

Belly sticks out bad balance shoulders back arms behind
X linked recessive
Most common dystrophy
Mutation of dystrophin gene
Rhabdomyolysis
Creatine kinase and myoglobin levels extremely high in blood
Sodium potassium phosphate uric acid also released
Adipose tissue replaces muscle

Question 24

Troponin assays

Answer 24

Cardiac muscle damage indicator (eg MI)

Question 25

Botulism toxin and Botox

Answer 25

Clostridium botulinum produces toxin, binds to ach receptors so muscles don’t contract

Question 26

Organophosphate poisoning

Answer 26

Inhibits ach esterase, which break down ach, stopping signal. Therefore stops relaxation

Question 27

Malignant hyperthermia

Answer 27

Anaesthetics- succinylcholine
Autosomal dominant inheritance - ryR1 gene
Males> females
Massive contractile fasciculation, muscle rigidity leading to excessive heat and metabolic acidosis
Hyperkalemia

Question 28

Follate deficiency and causes

Answer 28

Macrocytic megaloblastic Anaemia and symptoms
Muscle weakness
Depression
Diarrhoea reduced taste
Numbness and tingling in feet and hands

Poor diet
Increased require,ents (pregnancy increased erythropoisis severe skin disease)
Duodenum and jejunum disease eg coeliac and crohns
Alcoholism
Drugs
Liver disease or heart failure

Question 29

Osteogenesis imperfecta
(Brittle bone disease)

Answer 29

Mutation of COL1A gene
Incorrect collagen 1 fibres
Blue Sclera
Weak brittle bones
Flat or arched feet
Hearing loss
Shortened height

Question 30

Rickets/ osteomalacia

Answer 30

Vit D deficiency
Poor calcium mobilisation- ineffective mineralisation.
Weakened bone development
Soft bones
Bowed legs.
Surgery, stomach and intestine, kidney disease, no sunlight, certain drugs , eg phenytoin

Question 31

Osteoporosis

Answer 31

Loss of bone density,
Primary:
Type 1-
Post menopause - loss of oestrogen,
Increase osteoclast number
Smoking increased incidence
Type 2-
Older men and women
Loss of osteoblast function
Loss of both oestrogen and androgen

Secondary
Drug therapy- corticosteroids
Malnutrition, immobilisation, weightlessness
Metabolic bone diseases eg. Hyperparathyroidism, metastatic cancers

Question 32

Achondroplasia

Answer 32

Inherited mutation FGF3 receptor gene
FGF promotes collagen formation from cartilage.
Endochondrial ossification affected, intramembranous ossification not affected.
Therefore long bones can’t lengthen, short stature regular head and torso

Question 33

Cushing’s disease

Answer 33

ACTH- secreting pituitary tumour
High ACTH and Cortisol,
Low dose Dex suppression test, ACTH and Cortisol still high
High dose suppression test, ACTH and Cortisol low
Surgery/ radiotherapy,

Question 34

Cushing’s syndrome- Adrenal tumour

Answer 34

Cortisol - secreting adrenal adenoma
Low ACTH and high Cortisol,
Dex suppression test, Doesn’t affect cortisol
Surgery/ radiotherapy,