-
Question 1
Incorrect
-
Tumour necrosis factor is a cytokine. What is its major function?
Your Answer: Chemotaxis of neutrophils,
Correct Answer: Promotion of inflammation
Explanation:Tumour necrosis factor (TNF) is a cytokine that has a wide variety of functions. It can cause cytolysis of certain tumour cell lines; it is involved in the induction of cachexia; it is a potent pyrogen, causing fever by direct action or by stimulation of interleukin-1 secretion; it can stimulate cell proliferation and induce cell differentiation under certain conditions.
-
This question is part of the following fields:
- Immunology
- Medicine
-
-
Question 2
Correct
-
A 47 year old woman presents with joint pains and a history of recurrent infections over the past few months. Labs reveal a positive rheumatoid factor and low white cell count. Given the likely diagnosis, which of the following features would be present in her case?
Your Answer: Splenomegaly
Explanation:Felty syndrome is a severe subtype of seropositive Rheumatoid arthritis. Clinical triad consists of arthritis, splenomegaly, and neutropenia (leads to an increased risk of recurrent bacterial infections). Other symptoms include skin ulcers of the lower limbs (indicating vasculitis), hepatomegaly, fever, and chest pain (indicating pleuritis or pericarditis). It is associated with increased risk of developing non-Hodgkin lymphoma.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 3
Correct
-
Which part of the cerebellum is primarily responsible for equilibrium and eye movements?
Your Answer: Vestibulocerebellum
Explanation:The vestibulocerebellum develops at the same time as the vestibular apparatus in the inner ear. Its regulates balance between agonist and antagonist muscle contractions of the spine, hips, and shoulders during rapid movements.
-
This question is part of the following fields:
- Medicine
- Neurology
-
-
Question 4
Correct
-
Presence of which of the following indicates a worse prognosis in rheumatoid arthritis?
Your Answer: Anti-CCP antibodies
Explanation:Rheumatoid arthritis is both common and chronic, with significant consequences for multiple organ systems. Anti-cyclic citrullinated peptide (anti-CCP) antibody testing is particularly useful in the diagnosis of rheumatoid arthritis, with high specificity, presence early in the disease process, and ability to identify patients who are likely to have severe disease and irreversible damage. However, its sensitivity is low, and a negative result does not exclude disease. Anti-CCP antibodies have not been found at a significant frequency in other diseases to date, and are more specific than rheumatoid factor for detecting rheumatoid arthritis. The other factors that are mentioned do not play a key prognostic role.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 5
Correct
-
In meiosis, the period of prophase 1 involves:
Your Answer: Replicated DNA condensing to form visible chromosomes
Explanation:Prophase 1 has been divided into five different stages (laptotene, zygotene, pachytene, diplotene and diakinesis). In prophase 1, chromosomes are going to condense to become visible, each chromosome will contain two chromatids that are joined at the centromere.
-
This question is part of the following fields:
- Genetics
- Medicine
-
-
Question 6
Correct
-
Which one of the following interventions has the least role in management of acne rosacea?
Your Answer: Low-dose topical corticosteroids
Explanation:Mild cases are often not treated at all, or are simply covered up with normal cosmetics and avoiding sun exposure. Therapy for the treatment of rosacea is not curative, and is best measured in terms of reduction in the amount of facial redness and inflammatory lesions. The two primary modalities of rosacea treatment are topical and oral antibiotic agents (including metronidazole and tetracyclines). Laser therapy may be appropriate for patients with prominent telangiectasia.
-
This question is part of the following fields:
- Dermatology
- Medicine
-
-
Question 7
Correct
-
What is the effect of catecholamines (i.e. increased heart rate) on the pressure volume loop?
Your Answer: Shifts the diastolic pressure curve upward and leftward
Explanation:Catecholamines have a positive ionotropic and chronotropic effect on the heart. The ventricles develop greater tension during systole resulting in an increase in the stroke volume. The increase in stroke volume results in a decrease in the end diastolic volume. This pushes the loop towards the left and upwards.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 8
Correct
-
A 24-year-old student is brought to A&E having ingested at least 20 tablets of paracetamol 8 hours earlier. She weighs 61kg. What should her immediate management consist of?
Your Answer: Intravenous N-acetylcysteine
Explanation:Activated charcoal is useful if given within one hour of the paracetamol overdose. Liver function tests, INR and prothrombin time will be normal, as liver damage may not manifest until 24 hours or more after ingestion. The antidote of choice is intravenous N-acetylcysteine, which provides complete protection against toxicity if given within 10 hours of the overdose.
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 9
Incorrect
-
Activation of baroreceptor reflex involves:
Your Answer: Excitation of neurons in the rostral ventrolateral medulla (RVLM)
Correct Answer: Short term regulation of systemic blood pressure
Explanation:Baroreceptors are found in the heart and the blood vessels. They are the carotid sinus and the aortic arch receptors and respond to the minute to minute change in the blood pressure i.e. a change in the pulsatile pressure and not to a change in the mean arterial pressure. If the pulse pressure decreases, the rate of firing of the receptors decreases, stimulating an increase in the heart rate and blood pressure. Mechanisms that regulate the long term blood pressure control include the renin-angiotensin-aldosterone mechanism.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 10
Incorrect
-
A 25-year-old female presents to the emergency department with severe breathlessness and tinnitus. She is under treatment for asthma and depression with albuterol and amitriptyline respectively.On examination, she seems agitated with a BP of 100/44, a pulse rate of 112 bpm, a respiratory rate of 30 cycles/min, and a temperature of 37.8'C.An arterial blood gas performed reveals:pH: 7.48 (7.36 – 7.44)pO2: 11.2 kPa (11.3 – 12.6 kPa)pCO2: 1.9 kPa (4.7 – 6.0 kPa)Bicarbonate: 13 mmol/l (20 – 28 mmol/L)What is the most probable diagnosis?
Your Answer: Acute asthma exacerbation
Correct Answer: Salicylate poisoning
Explanation:The blood gas analysis provided above is suggestive of a mixed respiratory alkalosis and metabolic acidosis characteristic of salicylate overdose.Pathophysiology:The direct stimulation of the cerebral medulla causes hyperventilation and respiratory alkalosis.As it is metabolized, it causes an uncoupling of oxidative phosphorylation in the mitochondria. Lactate levels then increase due to the increase in anaerobic metabolism. This, along with a slight contribution from the salicylate metabolites result in metabolic acidosis.Tinnitus is characteristic and salicylate ototoxicity may produce deafness. Other neurological sequelae include encephalopathy and agitation, seizures and CNS depression and coma. Cardiovascular complications include tachycardia, hypotension, and dysrhythmias (VT, VF, and asystole).
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 11
Correct
-
A 64 year old woman who is of Asian descent and is diabetic (controlled by diet) presents with generalized body aches and difficulty rising from sitting for the last few months. Her blood glucose levels are in the normal range. Lab examination reveals normal blood cell count, low serum phosphate, calcium at the lower range, and raised alkaline phosphatase levels. Radiological examination shows which of the following?
Your Answer: Linear areas of low density
Explanation:Osteomalacia is a condition due to defective mineralization of osteoid. Occurs as a result of Vitamin D deficiency secondary to poor dietary intake and sun exposure, malabsorption e.g., inflammatory bowel disease and gastrointestinal bypass surgery. Radiological findings include reduced bone mineral density (a non specific finding), inability to radiologically distinguish vertebral body trabeculae (the film appears poor quality), looser pseudo fractures, fissures, or narrow radiolucent lines (these are the characteristic findings). Osteolytic or punched out lesions may be seen with multiple myeloma and bony metastases. Areas of sclerosis may be observed with conditions like osteosclerosis and Paget disease. A Brodie abscess is a subacute osteomyelitis, which may persist for years before progressing to a chronic, frank osteomyelitis.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 12
Correct
-
Following an action potential, cytosolic Ca2+ is increased. The binding of free Ca2+ to troponin C results in all of the following except:
Your Answer: Weakening of the troponin i interaction with actin
Explanation:At rest, troponin i is bound to actin and tropomyosin and covers the site where the myosin head interacts with actin. When Calcium enters into the muscle, it binds with troponin C and cause a structural change in troponin i which moves out of the myosin binding site and causes the cross bridges between the actin and myosin filaments to occur.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 13
Correct
-
A 68 year old man presents with acute symptoms of gout on his first metatarsophalangeal joint. Which option best explains the underlying mechanism of gout?
Your Answer: Decreased renal excretion of uric acid
Explanation:Primary gout is related more often to underexcretion of uric acid or overproduction.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 14
Incorrect
-
A 28 year old female presents to the rheumatology clinic for review. She has a history of adult onset Still's disease and complains of joint pains and persistent skin rash despite undergoing treatment with methotrexate and etanercept. On examination, an erythematous macular rash and active synovitis is noted. CRP is high (95 mg/dl). Which of the following interventions would be most appropriate?
Your Answer: Rituximab
Correct Answer: Anakinra
Explanation:Adult onset Still’s disease (AOSD) is an uncommon systemic inflammatory disease on the clinical spectrum of autoinflammatory disorders. Its presentation and clinical course may result in several well-differentiated phenotypes: from a systemic and highly symptomatic pattern to a chronic articular pattern. Overproduction of numerous pro-inflammatory cytokines is observed in AOSD. Anakinra, a human interleukin (IL)-1R antagonist, has recently been approved in the treatment of AOSD. Denosumab is a RANK ligand inhibitor used in the treatment of osteoporosis. Mepolizumab is used in the treatment of severe asthma with elevated eosinophils. There is some evidence to support the use of tocilizumab, an anti-IL6 monoclonal antibody in adult onset Still’s, but there is stronger data favouring the use of tocilizumab in the treatment of rheumatoid arthritis. Rituximab is usually reserved for patients who are unresponsive to anakinra.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 15
Correct
-
A 41 year old woman who has a history of SLE presents with a dry cough, dyspnoea and fever. She is being treated with a monthly dose of IV cyclophosphamide for Grade IV nephropathy. The last cyclophosphamide dose was 10 years ago. Lab investigations are as follows: WCC: 2.3 (lymphocyte count 0.7)Platelets: 81Hb: 10.5ESR: 56CRP: 43PO2: 7.2 kPa, PCO2: 3.6 kPa after walking out to the toilet.Chest X ray was unremarkable apart from some patchy pulmonary infiltration.What is the likely diagnosis?
Your Answer: Pneumocystis carinii pneumonia (PCP)
Explanation:Pneumocystis carinii pneumonia, is an opportunistic fungal lung infection occurring almost exclusively in immunocompromised individuals. In 50% of cases, PCP is the first manifestation of AIDS (acquired immune deficiency syndrome), but it may be caused by other immunodeficiency disorders. PCP should be suspected in patients with a history of progressive dyspnoea and a dry cough with resistance to standard antibiotic treatment. Signs that support this diagnosis include a CD4 count < 200/μL, an increased beta-D-glucan level, and diffuse bilateral infiltrates on chest x-ray. Management of PCP includes high-dose trimethoprim/sulfamethoxazole (TMP/SMX), treatment of the underlying immunodeficiency disorder, and steroids in the case of severe respiratory insufficiency. TB is less likely to be present in this case as ESR is relatively low and chest x-ray appeared normal.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 16
Correct
-
Which cell type functions as the critical bridge between innate and adaptive immune systems, by activating naïve T lymphocytes?
Your Answer: Dendritic cells
Explanation:Dendritic cells are antigen presenting cells. They express class II MHC and T cell co-stimulatory molecules. They bind antigens and present them to native T cells and in the process activate the specific T cell against that antigen.
-
This question is part of the following fields:
- Immunology
- Medicine
-
-
Question 17
Correct
-
Which of the following isoforms of Nitric oxide synthase (NOS) is found in endothelial cells?
Your Answer: Nos 3
Explanation:There are only 3 isoforms:NOS 1: found in nervous systemNOS 2: in macrophages and other immune cellsNOS 3: In endothelial cells
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 18
Incorrect
-
Regarding Gene Knockout Mouse Models, all are true except:
Your Answer: RFLP analysis is slow and cumbersome and is now largely obsolete
Correct Answer: In knockout mouse models a gene is turned on through targeted mutation
Explanation:In knockout mouse models, a gene is not turned on but rather turned off or “knocked out” through targeted mutation. This involves disrupting or deleting the gene to study the effects of its loss of function. Knockout models are crucial for understanding the roles of specific genes, particularly those with unknown functions.
The other statements are true:
- Knockout models are important in studying the roles of sequenced genes with unknown function.
- RFLP (Restriction Fragment Length Polymorphisms) can be subcategorized as SLP (single locus probe) and MLP (multi locus probe).
- RFLP analysis is slow and cumbersome and is now largely obsolete, having been replaced by more efficient techniques.
- Sequence changes involved in RFLP can be analyzed more quickly by PCR (Polymerase Chain Reaction).
-
This question is part of the following fields:
- Genetics
- Medicine
-
-
Question 19
Correct
-
Which of the following has the shortest duration:
Your Answer: Atrial systole
Explanation:Atrial systole: 0.1s
Atrial diastole: around 0.4s
Ventricular diastole: 0.4-0.53s
Ventricular systole: 0.27s
PR interval: 0.12-0.2 s
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 20
Correct
-
Which of the following enzymes are involved in Phase I drug metabolism?
Your Answer: Alcohol dehydrogenase
Explanation:Drug metabolism can be broadly classified into:Phase I (functionalization) reactions: also termed non-synthetic reactions, they include oxidation, reduction, hydrolysis, cyclization and de-cyclization. The most common and vital reactions are oxidation reactions. (Of the given enzymes only Alcohol dehydrogenase is involved in phase I drug metabolism. Succinate dehydrogenase, is a vital enzyme involved in the Kreb’s cycle and the mitochondrial electron transport chain). They are mainly catalysed by Cytochrome P-450 enzyme.Phase II (conjugation) reactions: occur following phase I reactions, they include reactions: glucuronidation and sulphate conjugation, etc. They are mostly catalysed by UDP-glucuronosyltransferase enzyme. Other phase II enzymes include: sulfotransferases, N-acetyltransferases, glutathione S-transferases and methyltransferases.
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 21
Correct
-
The superior orbital fissure is the site of entry/exit for which of the following group of nerves?
Your Answer: CN III, IV, V1, VI
Explanation:The superior and inferior divisions of oculomotor nerve (III), trochlear nerve (IV), lacrimal, frontal and nasociliary branches of ophthalmic V1 and the abducens nerve (VI)
-
This question is part of the following fields:
- Medicine
- Neurology
-
-
Question 22
Correct
-
Which of the following drug can cause galactorrhoea?
Your Answer: Metoclopramide
Explanation:Metoclopramide causes extrapyramidal effects (especially in children and young adults), hyperprolactinaemia, and occasionally tardive dyskinesia on prolonged administration. Also reported are drowsiness, restlessness, diarrhoea, depression, neuroleptic malignant syndrome, rashes, pruritus, oedema.
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 23
Incorrect
-
The main efferent input of the posterior pituitary gland comes from:
Your Answer: Sympathetic and parasympathetic stimulation from the hypothalamus
Correct Answer: Paracrine hormones secreted from the hypothalamus via axons.
Explanation:The posterior pituitary or neurohypophysis consists of a collection of axonal projections emerging from the hypothalamus. It releases hormones directly from these axonal endings into circulation; these hormones are oxytocin and vasopressin.
-
This question is part of the following fields:
- Endocrinology
- Medicine
-
-
Question 24
Correct
-
The hyperpolarization phase of pacemaker cells is dominated by ____ current.
Your Answer: K+
Explanation:The hyperpolarization phase is a continuation of the repolarization phase but the membrane potential dips below the resting membrane potential. This results due to the fact that the K+ channels take a longer time to close than the Na+ channels. Hence efflux of the K+ will result in hyperpolarization.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 25
Correct
-
A 49 year old female presents to the clinic complaining of pain in her left elbow that is localized to the left lateral epicondyle. She has spent the weekend painting her house. A diagnosis of lateral epicondylitis is suspected. The pain would characteristically worsen on which of the following movements?
Your Answer: Resisted wrist extension with the elbow extended
Explanation:Lateral epicondylitis (tennis elbow) is an overuse injury of the hand and finger extensor tendons that originate in the lateral humeral epicondyle that occurs following repeated or excessive pronation/supination and extension of the wrist (e.g., in racquet sports). Clinical features include pain and tenderness over the lateral epicondyle and along extensor muscles, thickening of the tendons. The examiner holds the patient’s hand with the thumb placed over the lateral epicondyle – The patient makes a fist, supinates the forearm, deviates radially, and extends the fist against the examiner’s resistance which results in pain over the lateral epicondyle. Conservative treatment includes rest, physiotherapy and orthotic braces. If this fails corticosteroids and lidocaine injections are employed. Surgery is indicated in patients with persistent symptoms despite 6 months of conservative treatment. Excision of abnormal tendon tissue; longitudinal incisions (tenotomies) in scarred and fibrotic areas to promote healing.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 26
Incorrect
-
Which of the following is a method for measurement of cardiac output?
Your Answer: Starling method
Correct Answer: Indicator dilution method
Explanation:There are two methods of calculating the cardiac output in humans other than doppler with echocardiography: The direct Fick’s method and the indicator dilution method. In the indicator dilution technique, a known amount of a substance such as a dye or, more commonly, a radioactive isotope is injected into an arm vein and the concentration of the indicator in serial samples of arterial blood is determined. The output of the heart is equal to the amount of indicator injected divided by its average concentration in arterial blood after a single circulation through the heart.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 27
Correct
-
Conjugation of proteins to which polypeptide marks them for degradation?
Your Answer: Ubiquitin
Explanation:Ubiquitin is a small regulatory protein that affects proteins in many ways: it can mark them for degradation via the proteasome, alter their cellular location, affect their activity, and promote or prevent protein interactions. Ubiquitination involves three main steps: activation, conjugation, and ligation,
-
This question is part of the following fields:
- Medicine
- Metabolism
-
-
Question 28
Correct
-
Question 29
Incorrect
-
Which one of the following is most likely to be seen in a patient with multiple endocrine neoplasia (MEN) type I?
Your Answer: Pheochromocytoma
Correct Answer: Insulinoma
Explanation:Multiple endocrine neoplasia type 1 (MEN-1 syndrome) or Wermer’s syndrome is part of a group of disorders, the multiple endocrine neoplasias, that affect the endocrine system through development of neoplastic lesions in the ‘three P’s’:Parathyroid (>90%): hyperparathyroidism due to parathyroid hyperplasiaPituitary (15-42%)Pancreas (60-70%, e.g. insulinoma, gastrinoma)
-
This question is part of the following fields:
- Endocrinology
- Medicine
-
-
Question 30
Correct
-
Where is the carotid sinus located?
Your Answer: After the bifurcation of the carotid artery, on the internal carotid
Explanation:The carotid sinus is a small dilation in the internal carotid artery just above its bifurcation into the external and internal carotid branch. Baroreceptors are present at this dilation.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
00
Correct
00
Incorrect
00
:
00
:
0
00
Session Time
00
:
00
Average Question Time (
Mins)