hllj/quesmed huggingface dataset:
A 37-year-old male presents to the emergency department after a motorcycle accident which has caused the rupture of his spleen.

During a tissue bleed, the clotting cascade is initiated. This also involves local vasoconstriction to prevent blood loss.

Which of the following molecules is involved in this vasoconstriction?

Options:
explanation: Plasmin is an enzyme which breaks down fibrin mesh into fibrin fragments such as D-dimer.
name: Plasmin
label: b
answer: no
explanation: Thrombin is a factor in the clotting cascade. It activates receptors on platelets to increase platelet aggregation and the release of von Willebrand factor from endothelial cells. It also converts fibrinogen into fibrin.
name: Thrombin
label: d
answer: no
explanation: Thromboxane A2 (TXA2) is released by activated platelets to cause platelet aggregation and vasoconstriction through TXA2 receptors.
name: Thromboxane A2
label: a
answer: yes
explanation: Tissue plasminogen activator is an enzyme released from endothelial cells which converts the inactive soluble circulating protein plasminogen into a potent proteolytic enzyme called plasmin.
name: Tissue plasminogen activator (tPA)
label: e
answer: no
explanation: Fibrinogen is a plasma protein which is converted to fibrin (by thrombin) to stabilise blood clots.
name: Fibrinogen
label: c
answer: no

Correct answer: a
The cardiac cycle describes the flow of blood through the heart.

What best describes the stage in the cardiac cycle that begins with the S2 heart sound?

Options:
explanation: Action potentials from the sinoatrial node coordinate synchronous atrial contraction. This increases the pressure in the atria above that in the ventricles, causing the tricuspid and mitral valves to open and the active filling of the ventricles. An **S4** heart sound may be heard here if the atria are contracting against a stiff or hypertrophic ventricle. This is a pathological heart sound.
name: Atrial contraction
label: c
answer: no
explanation: Ventricular filling occurs just after ventricular relaxation. Relaxation of the ventricular walls increases the internal volume of the ventricle which decreases the pressure. Due to passive filling and atrial contraction, the pressure in the atria increases and blood flows down the pressure gradient, filling the ventricles with blood. At this stage, the aortic and pulmonary valves are already closed. The **S3** heart sound may be heard here which indicates vigorous refilling of the ventricles. This may be heard in younger individuals and may not be pathological.
name: Ventricular filling
label: e
answer: no
explanation: Ventricular ejection refers to the flow of blood from the ventricles into the aorta and pulmonary artery. During this stage, the aortic and pulmonary valves are **open**. No heart sounds are heard during this stage.
name: Ventricular ejection
label: d
answer: no
explanation: Once blood has been ejected from the ventricles into the aorta and pulmonary artery, the pressure in these vessels becomes higher than the pressure in the ventricles. This causes the aortic and pulmonary valves to close to prevent backflow of blood into the heart. The S2 heart sound indicates the **closure** of the aortic and pulmonary valves.
name: Ventricular relaxation
label: a
answer: yes
explanation: During ventricular contraction, there is a higher pressure in the ventricles compared to the atria. To prevent backflow of blood into the atria, the mitral and tricuspid valves close. This is indicated by the **S1** heart sound.
name: Ventricular contraction
label: b
answer: no

Correct answer: a
A 43-year-old female presents to her GP with unilateral leg pain and swelling. The overlying skin is red and warmer compared to the other limb. A Doppler ultrasound confirms a DVT and further testing shows she has a protein C deficiency.

Activated protein C acts on which factors in the clotting cascade pathway?

Options:
explanation: Protein C and Protein S inhibit factor Va but do not inhibit factor IIa (this is inhibited by antithrombin).
name: Factors IIa and Va
label: e
answer: no
explanation: Antithrombin acts to inhibit factors Xa and IIa (thrombin). It can also inhibit factors VIIa, IXa, XIa and XIIa.
name: Factors Xa and IIa
label: c
answer: no
explanation: Protein C and Protein S inhibit factor Va but do not inhibit factor X directly.
name: Factors Va and X
label: d
answer: no
explanation: Protein C & Protein S inhibit factor Va, but do not inhibit factor Xa (this is inhibited by antithrombin).
name: Factors Va and Xa
label: b
answer: no
explanation: Activated protein C triggers protein S to inhibit factors VIIIa and Va.
name: Factors VIIIa and Va
label: a
answer: yes

Correct answer: a
A 37-year-old female presents to the emergency department with increased episodes of lightheadedness and a few episodes of fainting. She has also experienced chest pain for 3 days now.

Her heart rate is measured as 140 beats per minute. An ECG is performed and shows an irregularly irregular rhythm with no discrete p waves. She is currently haemodynamically stable.

What should be used to treat her?

Options:
explanation: Sinoatrial and atrioventricular nodes do not depend on sodium channels for depolarisation. Therefore blocking sodium channels has no effect.
name: Sodium channel blockers
label: b
answer: no
explanation: The irregularly irregular rhythm coupled with the lightheadedness and chest pain points to the diagnosis of atrial fibrillation. As the onset of symptoms started more than 48 hours ago, rate control is the recommended treatment option. Examples of rate control agents include beta-blockers such as bisoprolol and calcium channel blockers such as verapamil.
name: Beta-blocker
label: a
answer: yes
explanation: Potassium channel blockers such as amiodarone are used for rhythm control. As the onset of symptoms started more than 48 hours ago, rate control is the recommended treatment option.
name: Potassium channel blockers
label: d
answer: no
explanation: This is used in patients who are haemodynamically unstable, including if they are in shock.
name: Synchronised DC cardioversion
label: e
answer: no
explanation: This medication is only used in sedentary patients.
name: Digoxin
label: c
answer: no

Correct answer: a
The heart can generate electrical activity and contraction without external input.

Which of the following best describes the molecules involved in generating an unstable resting potential in the sino-atrial node which leads to the initiation of pacemaker potentials and determines heart rate?

Options:
explanation: Ryanodine receptors are found in myocytes, particularly on the membrane of the sarcoplasmic reticulum. They increase intracellular calcium levels which activates the troponin-tropomyosin system to cause heart muscle contraction. They are not involved in pacemaker potentials.
name: Ryanodine receptors
label: d
answer: no
explanation: Potassium efflux through voltage-gated potassium channels causes repolarisation of the sino-atrial node, terminating the pacemaker potential before the next potential starts.
name: K+ channels
label: c
answer: no
explanation: Voltage-gated calcium channels are activated once the membrane potential reaches the threshold. The firing of the action potential is due to the influx of calcium which causes a faster depolarisation.
name: Calcium channels
label: b
answer: no
explanation: IP3 receptors mediate calcium release from the endoplasmic reticulum. They are not involved in pacemaker potentials.
name: IP3 receptors
label: e
answer: no
explanation: Pacemaker potentials start with the slow depolarisation of pacemaker cells in the sino-atrial node towards the membrane potential threshold. If (funny current) channels allow sodium influx into cardiomyocytes resulting in this slow depolarisation. Once the membrane reaches the membrane potential threshold, it can fire an action potential.
name: If channels
label: a
answer: yes

Correct answer: a
A 69-year-old gentleman presents to A&E with central crushing chest pain which radiates to his jaw. The man appears to be breathless and sweating profusely. Blood tests reveal a troponin of 150 ng/litre (normal <14 ng/L) and ECG shows ST elevation in leads V1-V4.


Which of the following statements is correct?

Options:
explanation: Troponin is raised in both STEMI and NSTEMI as there is myocardial necrosis (death of the tissue) in both. Death of the myocardium causes the release of troponin into the blood.
name: Troponin is raised in STEMI and normal in NSTEMI
label: b
answer: no
explanation: In a STEMI, there is total occlusion of a coronary artery. This causes full-thickness (transmural) infarction in the muscular territory of the affected coronary artery. In NSTEMI, there is partial occlusion of a coronary artery which only affects the areas furthest away from the coronary artery (i.e. the innermost part of the myocardium, known as the subendocardium).
name: STEMI refers to a transmural infarction whereas NSTEMI refers to a subendocardial infarction
label: a
answer: yes
explanation: Cardiac enzymes are raised in both STEMI and NSTEMI as myocardial necrosis causes the release of these enzymes into the blood. The degree of necrosis varies in NSTEMI and STEMI, but there is still a rise in cardiac enzymes in both.
name: Cardiac enzymes are elevated in STEMI but normal in NSTEMI
label: c
answer: no
explanation: Pain at rest occurs in NSTEMI, STEMI and **unstable angina**. Stable angina is characterised by exertional pain which is relieved by rest and glyceryl trinitrate (GTN).
name: Pain at rest occurs in NSTEMI, STEMI and stable angina
label: d
answer: no
explanation: ST depression may occur in NSTEMI, unstable and stable angina (on exertion). It can also be seen in leads V1 - V3 in posterior STEMI. ST segment changes can be a sign of myocardial ischaemia.
name: ST segment depression only occurs in NSTEMI
label: e
answer: no

Correct answer: a
A 69-year-old male presents to his general practitioner due to difficulty in emptying his bladder and waking in the middle of the night to urinate. The GP prescribes him tamsulosin.

What is the mechanism of action of tamsulosin?

Options:
explanation: The inhibition of β3-adrenoreceptors causes contraction of the detrusor muscle. These would not help alleviate urinary symptoms.
name: β3 adrenergic receptor antagonist
label: d
answer: no
explanation: Activation of M3 receptors causes smooth muscle contraction in the bladder through the Gq receptor pathway. This would not alleviate urinary symptoms.
name: M3 muscarinic receptor agonist
label: c
answer: no
explanation: The stimulation of β3-adrenoreceptors causes relaxation of the detrusor muscle. An example of a β3 receptor agonist is mirabegron which is used to treat overactive bladder syndrome.
name: β3 adrenergic receptor agonist
label: e
answer: no
explanation: Tamsulosin is an alpha-1 adrenoceptor blocker. Blocking α1 receptors in the bladder causes detrusor muscle relaxation which improves urinary storage symptoms. This is used in conditions such as benign prostatic hyperplasia, which is what this gentleman is likely presenting with.
name: α1 receptor antagonist
label: a
answer: yes
explanation: This induces contraction of the internal urethral sphincter which prevents the flow of urine.
name: α1 receptor agonist
label: b
answer: no

Correct answer: a
A 73-year-old male presents to his GP with a 3-month history of shortness of breath which is worse on exertion and moderate leg swelling at the ankles.  When asked, he admits he has been finding it difficult to sleep flat and has to use a few pillows. He has a background history of aortic stenosis and hypertension and has a 30-pack-year history.

Which of the following heart failure medications only provide symptomatic relief?

Options:
explanation: ARB competitively bind to AT1 receptors on vascular smooth muscle preventing angiotensin II from binding and causing vasoconstriction. They have a mortality benefit in patients with heart failure.
name: Angiotensin receptor blockers (ARB)
label: e
answer: no
explanation: Beta-blockers work by decreasing preload and afterload and improving left ventricular function. They have a mortality benefit in patients with heart failure.
name: Beta-blocker
label: c
answer: no
explanation: ACE inhibitors decrease preload and afterload which increases cardiac output. ACE inhibitors do have a mortality benefit in heart failure and are strongly recommended as a first-line treatment.
name: ACE inhibitor
label: b
answer: no
explanation: These are potassium-sparing diuretics which promote sodium and water excretion. They also have a mortality benefit in patients with heart failure.
name: Aldosterone antagonists
label: d
answer: no
explanation: Loop diuretics, e.g. furosemide, are used for symptom management in heart failure. Loop diuretics promote diuresis by blocking sodium and chloride reabsorption. The overall effect of this is reduced shortness of breath and peripheral oedema.  There is not enough evidence to suggest that this improves survival.
name: Loop diuretics
label: a
answer: yes

Correct answer: a
A 40-year-old female presents to A&E with right upper quadrant pain, fever and vomiting. An ultrasound of the abdomen reveals an impacted stone in the neck of the gallbladder.

Which of the following is a factor involved in gallstone formation?

Options:
explanation: Nucleating factors such as mucin promote the crystallisation of cholesterol, which increases the risk of stones.
name: Low levels of nucleation
label: e
answer: no
explanation: Bacteria help in the formation of pigment stones by releasing lytic enzymes which can hydrolyse lecithin into fatty acids. This can bind to calcium to form brown mixed stones.
name: Chronic infection
label: a
answer: yes
explanation: Low levels of bile acids contribute to gallstone formation, for example, due to an ileal resection or malabsorptive conditions. A lower concentration of bile compared to cholesterol causes saturation of the bile and the formation of stones.
name: Increased amount of bile acids
label: b
answer: no
explanation: Gallbladder stasis promotes gallstone formation as impaired emptying results in a build-up of bile and an increased predisposition for stone formation. Gallbladder stasis may occur in pregnancy and diabetes.
name: Gallbladder hypermotility
label: d
answer: no
explanation: High cholesterol levels exceed the solubilising capacity of bile, causing the precipitation of bile into stones.
name: Low cholesterol
label: c
answer: no

Correct answer: a
A 62-year-old male attends his GP due to severe heartburn and epigastric pain. His symptoms are not relieved by ranitidine. Following a urea breath test, he is diagnosed as having *Helicobacter pylori*.

Which of the following is a virulence factor of *H pylori*?

Options:
explanation: This is an exotoxin which is secreted by *H pylori* that causes gastric mucosal injury.
name: Vacuolating toxin A (VacA)
label: a
answer: yes
explanation: This virulence factor is found in *Staphylococcus aureus* and *Clostridium perfringens*. It disrupts cell membranes.
name: Alpha toxin
label: e
answer: no
explanation: This is a virulence factor of influenza. It allows influenza to bind to host cell membranes to aid with infectivity.
name: Neuraminidase
label: b
answer: no
explanation: This is a virulence factor of *Staphylococcus aureus* and degrades hyaluronic acid between adjacent cells.
name: Hyaluronidase
label: d
answer: no
explanation: This is a virulence factor of influenza. It also allows influenza to bind to host cell membranes to aid with infectivity.
name: Haemagglutinin
label: c
answer: no

Correct answer: a
A 63-year-old male with a background history of diabetes and hypertension presents to Accident and Emergency with clamminess and palpitations. His ECG shows ST elevation in the lateral leads.

Which of the following is used in the immediate treatment of an ST elevated myocardial infarction?

Options:
explanation: This is used in long-term management if beta blockers are contraindicated (for example, in patients with asthma).
name: Calcium channel blockers
label: c
answer: no
explanation: This is used in long-term management. It is offered first-line alongside beta-blockers in patients with left ventricular dysfunction.
name: ACE inhibitors
label: d
answer: no
explanation: This is used in long-term management. They are offered first-line for at least 12 months after an MI.
name: Beta-blockers
label: b
answer: no
explanation: Streptokinase is a thrombolytic agent used to break down clots in myocardial infarction. It is offered to those who present within 12 hours of symptoms but are unable to undergo primary percutaneous coronary intervention (PCI).
name: Streptokinase
label: a
answer: yes
explanation: This is used in long-term management. This is a secondary prevention drug which reduces the risk of another MI occurring in the future by lowering cholesterol levels.
name: Statins
label: e
answer: no

Correct answer: a
Amino acids are broken down by transaminases into non-essential amino acids.

Which of the following is the correct reaction for the transamination of alanine?

Options:
explanation: Alanine does not react with oxaloacetate. Instead, the reaction between alanine and α-ketoglutarate forms glutamate which transfers its amino group to oxaloacetate.
name: Alanine + oxaloacetate ↔ pyruvate + aspartate
label: d
answer: no
explanation: Aspartate is not formed in the reaction between alanine and α-ketoglutarate.
name: Alanine + α-ketoglutarate ↔ pyruvate + aspartate
label: c
answer: no
explanation: Oxaloacetate is not formed in the reaction between alanine and α-ketoglutarate.
name: Alanine + α-ketoglutarate ↔ oxaloacetate + glutamate
label: e
answer: no
explanation: This is incorrect as glutamate transfers an amino group to oxaloacetate in the second transamination reaction. The reaction is as follows: Glutamate + oxaloacetate ↔ α-ketoglutarate + aspartate
name: Alanine + oxaloacetate ↔ pyruvate + glutamate
label: b
answer: no
explanation: The transamination of alanine (an amino acid) results in the transfer of an amino group to α-ketoglutarate, which is an amino-group acceptor, to produce glutamate, a new amino acid.
name: Alanine + α-ketoglutarate ↔ pyruvate + glutamate
label: a
answer: yes

Correct answer: a
Which of the following drugs is useful for decreasing colonic mass movement?

Options:
explanation: Lactulose works by increasing the volume of fluid in the lumen of the bowel via osmosis and causes peristalsis.
name: Lactulose
label: e
answer: no
explanation: This is used for treating infections,e.g. *Campylobacter jejuni*, that cause **diarrhoea**.
name: Erythromycin
label: d
answer: no
explanation: This is a stimulant laxative which stimulates peristalsis and therefore increases the motility of the large bowel.
name: Senna
label: b
answer: no
explanation: Loperamide is an opioid which can decrease intestinal motility and hence decrease the passage of faeces. This induces constipation.
name: Loperamide
label: a
answer: yes
explanation: This is a type of bulk-forming laxative. It contains fibre which uses water in the intestines to bulk the stool and improve its movement within the bowel. It does not affect intestinal motility.
name: Methylcellulose
label: c
answer: no

Correct answer: a
Which of the following is a feature of growth hormone excess?

Options:
explanation: Excess growth hormone causes excess insulin secretion.
name: Normal insulin levels
label: d
answer: no
explanation: Growth hormone excess increases gluconeogenesis which raises glucose levels.
name: Low glucose levels
label: c
answer: no
explanation: Growth hormone excess increases lipolysis raising free fatty acid levels.
name: Low free fatty acids
label: b
answer: no
explanation: Excess growth hormone causes excess insulin secretion. This decreases the number of insulin receptors and decreases their affinity for insulin which causes impaired glucose tolerance.
name: Impaired glucose tolerance
label: a
answer: yes
explanation: Excess growth hormone causes local insulin-like growth factor (IGF-1) overproduction. This acts on connective tissues and causes overgrowth. This causes hyperhidrosis (excess sweating).
name: Decreased sweating
label: e
answer: no

Correct answer: a
Which of the following statements on acute liver failure and acute liver injury is correct?

Options:
explanation: Acute liver failure is characterised by coagulopathy (INR> 1.5) and altered levels of consciousness due to hepatic encephalopathy. Acute liver injury is the initial trigger due to a primary liver aetiology and therefore does not present with encephalopathy.
name: Acute liver failure results in hepatic encephalopathy whilst acute liver injury does not
label: a
answer: yes
explanation: The most common cause of drug-induced liver injury and failure is paracetamol.
name: The most common cause of drug-induced acute liver injury and failure is amiodarone
label: d
answer: no
explanation: Acute liver injury and acute liver failure **both** cause an increase in hepatocellular (AST, ALT) and cholestatic (ALP, GGT) enzymes.
name: Acute liver injury results in increased ALT and AST but normal ALP whilst acute liver failure has raised AST, ALT and ALP
label: b
answer: no
explanation: Coagulopathy indicated by an INR >1.5 is a characteristic feature of acute liver failure and can also occur in acute liver injury.
name: Coagulopathy does not occur in acute liver failure but occurs in acute liver injury
label: c
answer: no
explanation: Patients should be treated with N-acetyl cysteine if ingestion of paracetamol is over 8 hours.
name: Patients should be treated with activated charcoal if ingestion of paracetamol is over 8 hours
label: e
answer: no

Correct answer: a
A 60-year-old male presents to his GP after noticing a new lesion on his cheek. On closer inspection, you notice a raised, flesh-coloured nodule approximately 4mm in diameter. You notice a pearly rolled edge and an ulceration in the centre of the lesion, with multiple small telangiectasia on the surface of the nodule.

Which of the following is the most likely diagnosis?

Options:
explanation: These are premalignant skins lesions that often precede the development of squamous cell carcinomas. Actinic keratosis present as lesions with surrounding erythema and a rough or warty surface. They are often described as incredibly itchy lesions on sun exposed areas of skin.
name: Actinic Keratosis
label: b
answer: no
explanation: These often appear as irregular red nodules with a scaly or crusty surface and irregular and raised margins. Unlike basal cell carcinomas, they can cause pain and bleeding and grow more quickly, over weeks to months.
name: Squamous cell carcinoma
label: e
answer: no
explanation: These often have a ‘stuck on’ appearance. They can range in colour from light to black. The lesion described in this question is more likely to be a basal cell carcinoma.
name: Seborrheic Keratosis
label: d
answer: no
explanation: This is a typical description of a basal cell carcinoma. Basal cell carcinomas usually present with the following three features: a pearly rolled edge, central ulceration and fine telangiectasias. They do not commonly present with any pain or bleeding. They are slow-growing and are more likely to appear on sun exposed areas of skin.
name: Basal cell carcinoma
label: a
answer: yes
explanation: Features of melanomas can be recognised using the ABCDE approach, which stands for: Asymmetrical lesion, Border irregularity, Colour variation, Diameter more than 6mm and Evolution over time. Melanomas can also be itchy or bleed and often grow more quickly than basal cell carcinomas.
name: Malignant melanoma
label: c
answer: no

Correct answer: a