hllj/quesmed huggingface dataset:
A doctor is enjoying a celebratory dinner out with his family when a call goes out for medical assistance as a person in the restaurant has just collapsed.

Which of the following best describes the duty of care of the doctor at this moment?

Options:
explanation: To win a claim for clinical negligence, the claimant must prove that a duty of care existed, that this duty was breached and that harm was caused by the breach. As there is no legal duty of care in this situation, the doctor is not at risk of a negligence claim. The doctor should still offer help though, but because there is a professional duty to do so.
name: The doctor should offer to help as he is at risk of a negligence claim if he does not
label: c
answer: no
explanation: GMC guidance states that doctors have a professional duty to offer assistance, taking into account their own safety, competence and availability of other options for care.
name: The doctor should not offer to help as there is no duty of care
label: e
answer: no
explanation: There is no Good Samaritan law in the UK, and therefore there is no legal duty of doctors to help injured or ill people in situations like this. If, for example, the doctor was a GP and the collapse happened inside the GP surgery when he was working, there would be a legal duty for the doctor to offer assistance.
name: The doctor should offer to help as there is a legal duty to do so
label: b
answer: no
explanation: Although there is indeed no Good Samaritan law in the UK, and therefore there is no legal duty of doctors to help injured or ill people, GMC guidance states that doctors have a professional duty to offer assistance.
name: The doctor should not offer to help, as there is no Good Samaritan law in place in the UK
label: d
answer: no
explanation: GMC guidance states that doctors have a professional duty to offer assistance, taking into account their own safety, competence and availability of other options for care. Failure to offer assistance in an emergency could prompt disciplinary action by the GMC.
name: The doctor should offer to help as there is a professional duty to do so
label: a
answer: yes

Correct answer: a
Which of the following statements about non-depolarising agents, such as atracurium and vecuronium, is true?

Options:
explanation: Depolarising muscle agents cause fasciculations (muscle twitching), just before paralysis occurs, as these agents work by depolarising the motor end plate.
name: They cause muscle fasciculations
label: c
answer: no
explanation: Non-depolarising agents are competitive antagonists of the nicotinic acetylcholine receptor, meaning that they block the receptor from letting in cations, so muscle relaxation is achieved. Depolarising agents are agonists of the receptor, causing receptor activation and cation influx.
name: They activate the nicotinic acetylcholine receptor, allowing cation influx
label: d
answer: no
explanation: Succinylcholine is a depolarising agent that causes muscle relaxation.
name: Succinylcholine is another non-depolarising agent that causes muscle relaxation
label: e
answer: no
explanation: As non-depolarising agents are competitive antagonists of the nicotinic acetylcholine receptor, an increase in acetylcholine will out-compete the drug for the receptor binding sites. Blocking the enzymes that break down acetylcholine allows this to occur.
name: Their action is reversed by acetylcholinesterases
label: a
answer: yes
explanation: Non-depolarising agents are competitive antagonists of the nicotinic acetylcholine receptor. They compete with acetylcholine for the orthosteric ligand binding site.
name: They bind to an allosteric site of the nicotinic acetylcholine receptors
label: b
answer: no

Correct answer: a
Which statement best describes the definition of the term ‘specificity’?

Options:
explanation: This is the definition of the statistical concept ‘number needed to treat’ (NNT). For example, if a drug has an NNT of 6, it means that 6 patients would have to be treated with the drug to prevent one additional detrimental outcome.
name: The number of patients over a given period that would need treatment to prevent a particular detrimental outcome
label: d
answer: no
explanation: This is the definition of positive predictive value, which is used in the evaluation of diagnostic tests. This can also be calculated from the sensitivity, specificity and prevalence of the condition.
name: The proportion of those who test positive for a disease that actually have the disease
label: c
answer: no
explanation: This is the definition of sensitivity, another measure used in the evaluation of diagnostic tests.
name: The probability that an individual with a disease will test positive for the disease
label: b
answer: no
explanation: This is the definition of the 95% confidence interval. For example, if the prevalence of a disease is measured as 0.9% (CI 0.73-1.08%), we can be 95% sure that the true value of the prevalence is between 0.73% and 1.08%.
name: The interval around an estimate in which there is 95% confidence that the true value lies
label: e
answer: no
explanation: This is the definition of specificity, which is a measure used to evaluate the suitability of diagnostic tests. Ideally, diagnostic tests should be highly sensitive and highly specific.
name: The probability that an individual without a disease will test negative for the disease
label: a
answer: yes

Correct answer: a
ACE (Angiotensin-Converting Enzyme) inhibitors are medications widely used in the treatment of hypertension and chronic kidney disease.

Which statement best describes the mode of action of ACE inhibitors?

Options:
explanation: The liver’s role in the renin-angiotensin-aldosterone system is to release angiotensinogen, which is then converted to angiotensin I by renin. The next step in the system is catalysed by ACE, an enzyme found on the surface of vascular endothelial cells predominantly in the lung.
name: They prevent the conversion of angiotensin I to angiotensin II in the liver
label: e
answer: no
explanation: Angiotensinogen is converted to angiotensin I by plasma renin released by the kidney. Angiotensin I is then converted to angiotensin II by ACE, which is inhibited by ACE inhibitors.
name: They prevent the conversion of angiotensinogen to angiotensin I in the lung
label: b
answer: no
explanation: Although they may somewhat indirectly affect renin release from the kidney, due to the negative feedback control of the renin-angiotensin-aldosterone system, this is not the primary mode of action of ACE inhibitors.
name: They directly inhibit the release of renin from the kidney
label: d
answer: no
explanation: Angiotensin II acts to increase blood pressure by multiple methods, acting as an endocrine, autocrine and intracrine hormone. ACE inhibitors do not have any major effect on the direct actions of angiotensin II on blood vessels.
name: They prevent the direct action of angiotensin II on blood vessels, therefore limiting vasoconstriction
label: c
answer: no
explanation: ACE inhibitors work by inhibiting ACE (angiotensin-converting enzyme). This is an enzyme which converts angiotensin I to angiotensin II and is found on the surface of vascular endothelial cells, predominantly in the lung.
name: They prevent the conversion of angiotensin I to angiotensin II in the lung
label: a
answer: yes

Correct answer: a
Which of the following describes a major reason why it is difficult to assess cause and effect in a cross-sectional study?

Options:
explanation: A confounding factor is something that is associated with the exposure and outcome and can distort the apparent relationship between them. All observational studies, such as cross-sectional studies, are subject to influence by confounding factors, however there are ways to minimise their effect (e.g. by performing adjusted analysis using statistical models).
name: There is no way to minimise the effect of confounding factors
label: d
answer: no
explanation: This is the case with case-control studies, which involve the selection of a group of subjects with the disease and a group of controls without the disease, and a comparison of their past exposure (risk factor) status.
name: There is a potential for recall error, as the exposure is assessed retrospectively
label: c
answer: no
explanation: Cross-sectional studies involve taking a sample of participants from a population of interest, and measuring exposure and disease outcome together at a single point in time. They are primarily used to assess disease prevalence of disease and are occasionally used to assess associations between exposure and disease. As the exposure and disease status are measured at the same time, it is difficult to establish cause and effect, as it is unknown which came first.
name: The exposure and disease outcome are measured at the same point in time
label: a
answer: yes
explanation: This is the case in randomised control trials, which are used to formally test the efficacy and safety of an intervention. If participants are lost to follow-up, drop out of the trial or discontinue treatment, this can affect results, however, this is not the case in observational studies such as cross-sectional studies.
name: Deviations from protocol can have a large impact on results
label: e
answer: no
explanation: This may be the case in randomised control trials or cohort studies. Cross-sectional studies do not involve the following up of participants over time.
name: As participants need to be followed up over a period of time, some participants may be lost-to follow-up
label: b
answer: no

Correct answer: a
Which statement best describes a feature of the post-synaptic receptors found at the neuromuscular junction?

Options:
explanation: The nicotinic acetylcholine receptors at the neuromuscular junction are ligand-gated ion channels, not G-protein coupled receptors. G-protein coupled receptors have a longer activation-to-effect time, which would not be useful at the neuromuscular junction, which needs to be able to respond quickly when activated.
name: Ligand binding causes a conformational change which activates an intracellular G-protein
label: b
answer: no
explanation: This is the structure of G-protein coupled receptors. Nicotinic acetylcholine receptors consist of 5 subunits, each with 4 transmembrane domains, surrounding a central pore.
name: They are monomeric receptors consisting of seven transmembrane domains
label: e
answer: no
explanation: Glutamate is the primary excitatory neurotransmitter in the central nervous system. The neuromuscular junction contains nicotinic receptors, which are activated by acetylcholine released from the presynaptic neuron.
name: They are activated by glutamate
label: c
answer: no
explanation: Nicotinic acetylcholine receptors are found in the neuromuscular junction and are ligand-gated ion channels. Following their activation by acetylcholine, the central channel opens, allowing sodium ions to enter the cell and potassium ions to exit the cell.
name: They are permeable to cations such as Na+ and K+
label: a
answer: yes
explanation: Suxamethonium is a nicotinic agonist- it activates the nicotinic receptors at the neuromuscular junction, not blocks them.
name: They are blocked by suxamethonium
label: d
answer: no

Correct answer: a
A 68-year-old man presents to his GP for his annual influenza vaccine.

Which of the following concepts is the single most likely explanation for why we have an annual influenza vaccination campaign?

Options:
explanation: Point mutations are single changes in the amino acid sequence of proteins through mutation. These changes are gradual over time, and would not cause influenza pandemics. It is important to remember that RNA viruses have a much higher error rate than DNA viruses because RNA polymerase has no proofreading activity.
TIP: you can remember R for rapid.
name: Point mutation
label: c
answer: no
explanation: Salicylic acid is the receptor on the host cell to which the influenza virus haemagglutinin (HA) protein binds to facilitate cellular entry. Mutations in salicylic acid proteins would not lead to influenza pandemics and would not require annual revaccination.
name: Salicylic acid mutation
label: d
answer: no
explanation: Antigenic drift is the natural evolution of viral strains due to selective pressure acting on point mutations. As the name suggests, this process is rather slow occurring, and would not produce a new strain of virus quickly to become a pandemic.
name: Antigenic drift
label: b
answer: no
explanation: Mutations in the influenza haemagglutinin (HA) protein lead to the process of antigenic drift. Antigenic drift is the natural evolution of viral strains due to selective pressure acting on point mutations. These mutations can occur in proteins such as haemagglutinin (HA) which bind to host salicylic acid receptors and facilitate viral entry.
name: Haemagglutinin mutation
label: e
answer: no
explanation: Viral genetic diversity can occur in numerous ways. Antigenic shift is the process by which two or more strains of the influenza virus recombine to produce a new, often more virulent subtype. This is the reason why the World Health Organisation predicts which strains of influenza will be virulent in the coming winter, and initiate target-group-specific annual vaccination campaigns.
name: Antigenic shift
label: a
answer: yes

Correct answer: a
A 10-day-old baby girl presents to ED with a fever, vomiting and a non-blanching rash. The team are concerned that this may be a presentation of bacterial meningitis.

Which of the following organisms is the most likely cause of this presentation?

Options:
explanation: *Staphylococcus aureus* is the leading cause of skin infections, not meningitis. Complications include bone and joint infections, pneumonia and sepsis.
name: *Staphylococcus aureus*
label: d
answer: no
explanation: Neisseria meningitidis is a Gram-negative diplococcus which is associated with meningitis in adults, not in neonates.
name: *Neisseria meningitidis*
label: b
answer: no
explanation: Meningitis refers to the inflammation of the meninges.

Meningitis is a serious and notifiable disease. If meningitis is suspected, all patients must be transferred to the hospital urgently.

Neonates are exposed to Group B Streptococcus in the mother's vaginal canal upon birth and can develop meningitis. Symptoms include a high fever, headache, stiff neck, photophobia and seizures. Characteristically, but not always, meningitis presents with a non-blanching rash.
name: *Streptococcus agalactiae*
label: a
answer: yes
explanation: *Listeria monocytogenes* is an opportunistic pathogen which causes meningitis in immunocompromised and elderly patients, not in neonates.
name: *Listeria monocytogenes*
label: c
answer: no
explanation: Although poliovirus is a major cause of meningitis, the question is asking for a bacterial cause, so a virus would not be the appropriate answer. Other viruses which are associated with meningitis include HSV1, paramyxoviruses (mumps), and measles.
name: *Poliovirus*
label: e
answer: no

Correct answer: a
An 89-year-old man in a nursing home has just finished a course of co-amoxiclav following a recent community-acquired pneumonia. Shortly after this, he develops bouts of watery, bloody diarrhoea and painful abdominal cramps.

Which of the following organisms is the most likely cause of this patient's presentation?

Options:
explanation: Clostridium difficile (C. diff) is an opportunistic Gram-positive bacteria, which causes pseudomembranous colitis which is commonly seen in patients who have recently been on a course of broad-spectrum antibiotics (and thus have a brief immunocompromised state, allowing them to succumb to infection). Features of C. diff-associated colitis (inflammation of the colon) include watery (and sometimes bloody) diarrhoea and high fever leading to dehydration.
name: *Clostridium difficile*
label: a
answer: yes
explanation: Rotavirus is an enterovirus which is commonly acquired through contaminated water or food and is associated with diarrhoea which is not usually bloody and does not lead to systemic illness (i.e. fever). The symptoms described above (high fever and bloody diarrhoea) are more commonly associated with bacterial gastroenteritis.
name: *Rotavirus*
label: b
answer: no
explanation: People who acquire Campylobacter jejuni often present with diarrhoea (often bloody), fever and abdominal pain described above. Campylobacter jejuni infections are often acquired after ingesting undercooked meat and do not typically occur after a course of antibiotics.
name: *Campylobacter jejuni*
label: d
answer: no
explanation: Although polio is an enterovirus and spreads via the faecal-oral route, it is not associated with causing diarrhoea or symptoms of gastroenteritis. Often people with poliovirus infection report flu-like symptoms of sore throat, headaches and fatigue.
name: *Poliovirus*
label: c
answer: no
explanation: Helicobacter pylori is a common cause of stomach (peptic) ulcers and are not associated with symptoms of acute gastroenteritis described above.
name: *Helicobacter pylori*
label: e
answer: no

Correct answer: a
Which of the following options correctly matches the virus to its primary mode of transmission?

Options:
explanation: *Influenza* viruses are orthomyxoviruses which classically spread via respiratory aerosols, primarily through coughing and sneezing.
name: *Influenza* -- faecal-oral transmission
label: c
answer: no
explanation: Cytomegalovirus is a common cause of congenital malformations. It can be spread in utero through a transplacental route from the mother to the baby. Additionally, the virus can transmit through bodily fluids and sexual contact.
name: *Cytomegalovirus* (CMV) -- arthropod (insect) transmission
label: e
answer: no
explanation: Rabies is spread through direct contact, commonly via wounds acquired from animal bites. The virus enters axons through saliva and disseminates into the central nervous system. Rabies causes untreatable encephalitis, so immediate prophylaxis should be administered upon suspected exposure.
name: Rabies -- sexual transmission
label: d
answer: no
explanation: *Measles* is a negative single-stranded RNA virus spread via airborne transmission and enters the respiratory tract. Measles is one of the three viruses which constitute the MMR vaccine (measles, mumps and rubella).
name: *Measles* -- airborne transmission
label: a
answer: yes
explanation: *Poliovirus* is a single-stranded RNA virus which is transmitted through the faecal-oral route. The virus enters through the gut but disseminates into the central nervous system (CNS) through lymphatics.
name: *Poliovirus* -- blood-borne transmission
label: b
answer: no

Correct answer: a
A 63-year-old man presents to his GP with shortness of breath and swollen feet. He had a recent streptococcal pyogenes infection three weeks ago. Upon examination, a murmur is heard consistent with mitral valve regurgitation, thought to be a consequence of the infection.

Which of the following options most closely describes the systemic complication he is experiencing?

Options:
explanation: Although post-streptococcal glomerulonephritis develops in the time frame described in the scenario (1-3 weeks), this is an incorrect answer as there is no mention of glomerulonephritis symptoms in the stem. Post-streptococcal glomerulonephritis is caused by immune complex deposition in the kidneys causing kidney damage. This leads to a loss of filtration ability and function.
name: Post-Streptococcal Glomerulonephritis
label: b
answer: no
explanation: Toxic Shock Syndrome is a serious and life-threatening complication of *Streptococcus pyogenes* infection caused by an immune 'overreaction' to the streptococcus pyrogenic exotoxins A and C.
name: Toxic Shock Syndrome
label: c
answer: no
explanation: Although post-streptococcal reactive arthritis is a complication of streptococcal pyogenes infection, it does not fit the stem description. Classically, in post-streptococcal reactive arthritis, numerous joints (polyarthritis) are affected, and the condition "fleets" between them.
name: Post-Streptococcal Reactive Arthritis
label: e
answer: no
explanation: Rheumatic fever is a complication of a *Streptococcus pyogenes* infection. It is caused by molecular mimicry when epitopes are shared between the host and the bacterium, namely the Streptococcal M protein. This leads to the immune system mistaking host tissues as 'foreign,' and causes immune cross-reactivity with cardiac myosin. The scenario describes a subsequent complication known as mitral valve regurgitation which presents with shortness of breath and oedema.

Tip: Remember, M for molecular mimicry!
name: Rheumatic fever
label: a
answer: yes
explanation: Scarlet fever is a complication of *Streptococcus pyogenes* infection. Scarlet fever would present with a fever, abdominal pain and vomiting, as well as a characteristic 'strawberry' tongue.
name: Scarlet Fever
label: d
answer: no

Correct answer: a
Which of the following laboratory techniques is the best confirmatory diagnostic investigation for Mycobacterium tuberculosis?

Options:
explanation: Tissue culture involves growing cells and inoculating them with infectious organisms to investigate organism growth. Although *Mycobacterium tuberculosis* culture is available, the process itself may take 4-8 weeks and thus is not used routinely for diagnostic purposes.
name: Tissue culture
label: c
answer: no
explanation: *Mycobacterium tuberculosis* is the causative organism of tuberculosis. They have a very thick lipid-rich wall, so Gram staining is not helpful for investigation. Thus, for direct microscopy, a special stain called the Ziehl-Neelsen stain is used to visualise the mycobacteria.
name: Ziehl Neelsen stain
label: a
answer: yes
explanation: Light microscopy is not sensitive enough for *Mycobacterium tuberculosis* visualisation. The preferred method is fluorescence microscopy, commonly done with auramine staining.
name: Light microscopy
label: e
answer: no
explanation: Plaque assays are an investigation used for counting viruses in a certain sample. A monolayer of cells is grown, and a set amount of sample is diluted. A plaque, which is an area of cell destruction becomes visible, and the concentration of virus particles in the original sample is inferred. *Mycobacterium tuberculosis* is not a virus, it is a bacteria.
name: Plaque assay
label: d
answer: no
explanation: Gram stain classifies bacteria by the colour they stain which reflects certain bacterial properties (differences in cell wall composition and embedded proteins). *Mycobacterium tuberculosis* is not truly Gram-positive or negative, and so this type of stain is not sensitive enough for this class of organism.
name: Gram stain
label: b
answer: no

Correct answer: a