Anatomy
How would an abducens nerve palsy present?
Lateral rectus affected = inability to abduct the affected eye beyond the midline
List 3 effects of adrenaline in treating anaphylaxis
Increases heart rate
Increases myocardial contraction
Increases renin release
Induces bronchodilation
Vasoconstriction
What are the four classic subtypes of Hodgkin lymphoma?
Nodular sclerosis
Mixed cellularity
Lymphocyte-rich
Lymphocyte-depleted
List 4 signs of an allergic response
Urticaria
Oedema
Wheeze
Dyspnoea
Eczema
In Horner's syndrome, which structure is compressed with an apical lung tumour?
Sympathetic ganglion
MOA of chloroquine and quinine
Enters the food vacuole and inhibits haem polymerase = inhibits haem --> haemozoin conversion
Haem buildup is toxic for plasmodium and poisons it
List 4 causes of iron deficiency anaemia
Poor dietary intake of iron
Poor absorption of iron
Blood loss
Increased demand of iron
List 3 signs of severe dehydration in a 12 month old
Sunken fontanelle
Lethargy and weakness
Behavioural changes (e.g. decreased engagement)
Decreased urine output
Decreased skin turgor
Tachycardia
Tachypneoa
How would a trochlear nerve palsy present in a patient?
Superior oblique paralysis = inability to depress and twist eyes inward
MOA of allopurinol in the treatment of gout
Used prophylactically - inhibits enzyme xanthase oxidase = inhibits conversion of hypoxanthine to xanthine to uric acid
Hence reduces serum and urine levels of uric acid
List 3 causes of premature ventricular contractions
Localised areas of ischaemia
Calcification of vessels or muscles
Irritation of AV node, Purkinje fibres, or myocardium
Cardiac catheterisation
Plasma electrolyte imbalances
List 6 clinical signs of congestive heart failure
Swelling in ankles, legs, or abdomen
Tachycardia
Dyspnoea
Arrhythmia
Elevated JVP
Hepatomegaly
Cough / wheeze
Displaced apex beat
Right ventricular heave
What structures normally form the left border of the heart?
Left ventricle and left atrial appendage
MOA of ACE inhibitors in treatment of heart failure
ACE inhibitors inhibit conversion of angiotensin 1 --> angiotensin 2
Reduces: vasoconstriction, cardiac afterload, aldosterone secretion
Outcome: reduces sodium and water retention = reduced oedema = decreased central venous pressure and decreased vascular resistance
Outline the function of IL-2. What is the effect of calcineurin?
IL-2 is a pro-inflammatory cytokine which regulates lymphocyte activity by stimulating growth and differentiation.
Calcineurin upregulates IL-2 expression
List 4 signs of a severe malaria infection
Severe anaemia
Renal failure
Delirium
Hyperhaemoglobinuria
Normally, which vessel would the lesser saphenous vein drain into?
Popliteal vein
MOA of cyclosporine
Inhibits actions of calcineurin = reduces IL-2 production = reduces growth, activation, and differentiation of lymphocytes
How do mutations in CDKN2A, RAS / BRAF, and MC1R contribute to an increased risk of melanoma?
CDKN2A - cell cycle control: encodes for p14 / ARF, p15, and p16 tumour suppressors. p16 reinforces RB tumour suppressors to block cells passing through the cell cycle; ARF enhances p53 tumour suppressor activity
RAS / BRAF - pro-growth signalling pathways: increased signalling promotes cell growth and survival
MC1R - melanocortin receptor: mutation impairs production of melanin which is needed to block UVB radiation
List 5 CXR features of congestive heart failure
Alveolar oedema
Kerley B lines
Cardiomegaly
Dilated upper lobe vessels
Pleural effusion