Past paper Flashcards
- Which of the following is not correct about insulin?
A. Rising blood glucose level leads to a rise in insulin secretion
B. It facilitates glycogen and triglyceride synthesis
C. Insulin infusion lowers plasma potassium concentration
D. The insulin receptor is a tyrosine-protein kinase
E. Diabetes patients with advanced diabetic nephropathy requires treatment by higher dosage of insulin
E
- Which of the following is NOT a mechanism of diabetic complications?
A. Protein glycation
B. Increased production of creatinine
C. Insulin resistance
D. Increased liver production of VLDL cholesterol
E. Excretion of albumin in urine
B
(creatinine production increases with increase muscle mass)
- Which of the following does not indicate the result of protein glycation?
A. Urine albumin
B. HbA1c
C. Fructosamine
D. Oxidized LDL
E. Plasma glucose
E
Glycation of glomerular basement membrane leads to loss of negative charges, causing microalbuminuria (30-300 mg/day) and DM nephropathy.
Glycation of apolipoproteins on LDL particles increases their atherogenicity, thus predisposing to atherosclerosis.
HbA1c is glycated hemoglobin used as a marker of mean glucose level over past 60 days.
Fructosamine, glycated albumin, 1,5-anhydroglucitol are other markers for DM, if HbA1c is inaccurate in some situations, e.g. splenectomy, hemolytic anemia.
Name 3 analytes that are included in a urine dipstick test that is most relevant to his management (HHS patient)
glucose, ketone, protein
Which of the following is recognised by TLR4
A. Bacterial DNA
B. G+ peptidoglycan
C. Flagellin
D. G- LPS
E. dsRNA
D
Suggest 2 biochemical Ix to differentiate different sources of ALP
GGT
isoenzyme electrophoresis
Biochemical test for vitamin D
calcidiol
Why PTH level increases in vitamin D insufficiency?
vitamin D normally suppresses PTH synthesis
The patient (DKA) was given IV fluid and insulin. Urine ketones became from negative to positive. Why?
Urine ketostix mainly detects acetoacetate but not β-hydroxybutyrate
↑ NADH/NAD ration in DKA –> stimulate conversion of acetoacetate into β-hydroxybutyrate –> cannot be detected by ketostix –> false negative
after insulin replacement –> NADH/NAD ratio is restored –> urine ketones turn positive
Explain the high urine myoglobin level in a road traffic accident victim
serious trauma –> rhabdomyolysis –> high plasma myoglobin concentration –> exceed reabsorptive threshold in kidneys –> overflow proteinuria –> high urine myoglobin
Calculate and comment on the protein excretion
( volume: 1.25L
protein: 6 g/L )
Protein excretion = 6 × 1.25 = 7.5 g
Protein excretion is higher than normal, as protein excretion = 7500 mg > 150 mg/day, indicating proteinuria
There is nephrotic syndrome as protein excretion = 7500 mg > 3500 mg/day
Which of the following is not helpful in investigating for neuroblastoma?
A. urine HVA (homovanillic acid)
B. urine VMA (vanillylmandelic acid)
C. urine dopamine
D. 5-HIAA (5-hydroxyindoleacetic acid)
E. tumour stage
D
Which of the following is not produced by carcinoid tumours?
A. Serotonin
B. Histamine
C. 5-hydroxytryptophan
D. Tryptophan
E. 5-hydroxyindoleacetic acid
D
Which of the following is NOT correct about the renin-angiotensin system?
A. Renin is produced by juxtaglomerular apparatus.
B. Angiotensin II stimulates aldosterone secretion.
C. Angiotensin converting enzyme (ACE) inhibitor is used to treat hypertension caused by renal artery stenosis.
D. Angiotensin converting enzyme (ACE) inhibitor is used to treat hypertension in diabetic patients.
E. Angiotensin converting enzyme (ACE) is produced by the lung.
C
Which of the following is incorrect concerning the metabolic screening using cord blood and heel prick blood sample?
A. Cord blood sample is collected immediately after birth
B. Cord blood sample is less invasive than dried blood spot sampling
C. Cord blood sample is commonly used in developed countries for newborn metabolic screening
D. Cord blood sample can screen for most inborn error of metabolism
E. Heel prick blood sample should be collected 24hr to 7 days afterwards
D
