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  • Question 1 - Which of the following is NOT a common side effect of amiodarone: ...

    Correct

    • Which of the following is NOT a common side effect of amiodarone:

      Your Answer: Blue/green teeth discolouration

      Explanation:

      Common side effects of amiodarone include: Bradycardia, Nausea and vomiting, Thyroid disorders – hypothyroidism and hyperthyroidism, Persistent slate grey skin discoloration, Photosensitivity, Pulmonary toxicity (including pneumonitis and fibrosis), Hepatotoxicity, Corneal microdeposits (sometimes with night glare), Peripheral neuropathy and Sleep disorders.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      5.1
      Seconds
  • Question 2 - An elderly man presents with bilateral lower facial swelling around the mandible and...

    Correct

    • An elderly man presents with bilateral lower facial swelling around the mandible and upper neck. A CT scan of his neck was performed and the results were conclusive with Ludwig's angina.

      Which of the following spaces is most likely affected based on the case presented?

      Your Answer: Submandibular space

      Explanation:

      Ludwig’s angina is life-threatening cellulitis of the soft tissue involving the floor of the mouth and neck. It involves three compartments of the floor of the mouth: the sublingual, submental, and submandibular.

      Ludwig’s angina usually originates as a dental infection of the second or third mandibular molars. The infection begins in the subgingival pocket and spreads to the musculature of the floor of the mouth. It progresses below the mylohyoid line, indicating that it has moved to the sublingual space. As the roots of the second and third mandibular molars lie below this line, infection of these teeth will predispose to Ludwig’s angina. The infection spreads lingually rather than buccally because the lingual aspect of the tooth socket is thinner. It initially spreads to the sublingual space and progresses to the submandibular space.

      The disease is usually polymicrobial, involving oral flora, both aerobes, and anaerobes. The most common organisms are Staphylococcus, Streptococcus, Peptostreptococcus, Fusobacterium, Bacteroides, and Actinomyces.

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
      7.4
      Seconds
  • Question 3 - Regarding the trachea, which of the following statements is INCORRECT: ...

    Correct

    • Regarding the trachea, which of the following statements is INCORRECT:

      Your Answer: A cricothyrotomy involves making an opening in the neck inferior to the cricoid cartilage.

      Explanation:

      A cricothyrotomy involves making an opening in the median cricothyroid ligament (the medial part of the cricothyroid membrane), between the cricoid cartilage below and the thyroid cartilage above.

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
      12.2
      Seconds
  • Question 4 - A 57-year-old woman has presented with cough and shortness of breath. Her GP...

    Correct

    • A 57-year-old woman has presented with cough and shortness of breath. Her GP had done some blood tests recently and told her that she had a positive ANA result.

      Which of these statements is true about anti-nuclear antibodies (ANAs)? Select only ONE answer.

      Your Answer: The presence of ANAs in rheumatoid arthritis is suggestive of Felty’s syndrome

      Explanation:

      Anti-nuclear antibodies are auto-antibodies directed against a variety of nuclear antigens. There are different staining patterns and each pattern is suggestive of a different disorder.

      Speckled staining is suggestive of mixed connective tissue disease.

      Nucleolar staining is suggestive of scleroderma, while homogenous staining is suggestive of lupus.

      Anti-double stranded DNA is suggestive of SLE while anti-histone antibodies are suggestive of drug-induced lupus.

      ELISA testing is cheaper but not the most accurate means of testing for ANAs. Indirect immunofluorescence testing is the most accurate.

      The presence of ANAs in rheumatoid arthritis is suggestive of Felty’s syndrome. Felty’s syndrome is characterized by a combination of rheumatoid arthritis, splenomegaly and neutropenia.

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      18.8
      Seconds
  • Question 5 - A 40-year-old woman was rushed to the Emergency Department due to an anaphylactic...

    Correct

    • A 40-year-old woman was rushed to the Emergency Department due to an anaphylactic reaction after being stung by a bee. She responded well to initial treatment but developed anaphylactic symptoms after 6 hours. Her symptoms were resolved after a further dose of adrenaline. Her family threatened legal action as they thought she had not received adequate treatment but withdrew their accusation after the attending physician explained that the woman had suffered a biphasic reaction.

      What is the approximate percentage of people who suffer this type of reaction?

      Your Answer: 20%

      Explanation:

      Anaphylactic reactions are Type 1 hypersensitivity reactions IgE-mediated and can be potentially life-threatening if not treated promptly. There are four well-recognized patterns of anaphylaxis:
      1) Uniphasic
      2) Biphasic
      3) Protracted
      4) Refractory

      Biphasic reactions occur in 20% of the population, although their mechanism is poorly understood. The symptoms of anaphylaxis recur within 4-6 hours, although they may also recur up to 72 hours later. All patients discharged from the hospital after an anaphylactic shock must:
      1) Be warned to return to the hospital immediately if symptoms recur
      2) Have a treatment plan in place
      3) Have a follow-up appointment
      4) Be considered for an adrenaline auto-injector
      5) Referred to an allergy clinic

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      8.9
      Seconds
  • Question 6 - Myocardial contractility is best correlated with the intracellular concentration of: ...

    Correct

    • Myocardial contractility is best correlated with the intracellular concentration of:

      Your Answer: Ca2+

      Explanation:

      Contractility of myocardial cells depends on the intracellular [Ca2+], which is regulated by Ca2+entry across the cell membrane during the plateau of the action potential and by Ca2+uptake into and release from the sarcoplasmic reticulum (SR).

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      8.2
      Seconds
  • Question 7 - Typically, granulomatous inflammation is associated with one of the following infections: ...

    Correct

    • Typically, granulomatous inflammation is associated with one of the following infections:

      Your Answer: Tuberculosis

      Explanation:

      Granulomatous inflammation is typically seen when an infective agent with a digestion-resistance capsule (e.g. Mycobacterium tuberculosis) or a piece of inert foreign material (such as suture or glass) is introduced into the tissue. A transient acute inflammatory response occurs and when this is ineffective in eradicating the stimulus, chronic inflammation occurs.

      Tuberculosis is the prototype of the granulomatous diseases, but sarcoidosis, cat-scratch disease, lymphogranuloma inguinale, leprosy, brucellosis, syphilis, some mycotic infections, berylliosis, reactions of irritant lipids, and some autoimmune diseases are also included

    • This question is part of the following fields:

      • Inflammatory Responses
      • Pathology
      3.5
      Seconds
  • Question 8 - The least likely feature expected to be seen in a lesion of the...

    Correct

    • The least likely feature expected to be seen in a lesion of the frontal lobe is which of the following?

      Your Answer: Loss of two-point discrimination

      Explanation:

      Lesions in different areas give rise to different symptoms.
      Lesions of the parietal lobe give rise to loss of two-point discrimination.
      Lesions to Broca’s area give rise to expressive dysphasia results from damage
      Lesions to the primary motor cortex give rise to contralateral weakness of the face and arm.
      Lesions to the prefrontal cortex give rise to personality change.
      Lesions to the frontal eye field give rise to conjugate eye deviation towards side of lesion.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      9.6
      Seconds
  • Question 9 - A patient who is a known case of rheumatoid arthritis presents to the...

    Correct

    • A patient who is a known case of rheumatoid arthritis presents to the clinic as his grandson was recently diagnosed with chickenpox. His grandson spent the weekend with her, and he was in close contact with him. He takes 50 mg of prednisolone once daily and has been for the past six months. There is no history of chickenpox.

      Out of the following, which is TRUE regarding the next plan of action for her care?

      Your Answer: She should receive prophylactic varicella-zoster Immunoglobulin (VZIG)

      Explanation:

      Varicella-zoster immunoglobulin (VZIG) is indicated for post exposure prevention and treatment of varicella. It is recommended as prophylaxis for high-risk patients with no known immunity (i.e. no known previous chickenpox) who have had a significant exposure to varicella-zoster (considered >4 hours close contact).

      The high-risk groups are:
      1. Neonates
      2. Pregnant women
      3. The immunocompromised (e.g. cancer, immunosuppressive therapies)
      4. Those on high dose steroids (children on more than 2 mg/kg/day for more than 14 days, or adults on 40 mg/day for more than a week)

      This patient is at high risk of developing adrenal insufficiency and may need a temporary increase in her steroid dose during infection or stress. It would be inappropriate to stop or wean down her dose of prednisolone and can cause side effects.

      Since he is on steroids without immunity for chickenpox, he is at risk of developing severe varicella infection, with possible complications including pneumonia, hepatitis and DIC.

      If he develops a varicella infection, he will need to be admitted and require a specialist review and intravenous Acyclovir.

    • This question is part of the following fields:

      • Immunological Products & Vaccines
      • Pharmacology
      14.6
      Seconds
  • Question 10 - A 55-year-old woman was complaining of headaches. On examination, the patient is found...

    Correct

    • A 55-year-old woman was complaining of headaches. On examination, the patient is found to have weakness on the left side of her body and her eyes are deviated towards the right hand side. These are signs of damage to which of the following areas?

      Your Answer: Frontal lobe

      Explanation:

      Some potential symptoms of frontal lobe damage can include loss of movement, either partial or complete, on the opposite side of the body.

      In the patient’s case, it is a result of motor cortex damage on the right side since her left side of the body is affected. The conjugate eye deviation symptom towards the side of the lesion is a result of damage to the frontal eye field.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      18.1
      Seconds
  • Question 11 - Regarding hepatitis A, which of the following statements is CORRECT: ...

    Correct

    • Regarding hepatitis A, which of the following statements is CORRECT:

      Your Answer: Anti-HAV IgM antibodies are diagnostic.

      Explanation:

      Anti-HAV IgM antibodies are diagnostic. Disease in children is more commonly asymptomatic, risk of symptomatic disease increases with age. Transmission is by the faecal-oral route. Faecal shedding has been demonstrated for 2 – 3 weeks before and about a week after, the onset of jaundice. Infection confers lifelong immunity.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      8.5
      Seconds
  • Question 12 - A 23-year-old man is discovered to have an infection from Helicobacter pylori.

    Which...

    Correct

    • A 23-year-old man is discovered to have an infection from Helicobacter pylori.

      Which of the following types of cancer is mostly associated with Helicobacter pylori infection?

      Your Answer: Gastric cancer

      Explanation:

      H. pylori is recognized as a major cause of type B gastritis, a chronic condition formerly associated primarily with stress and chemical irritants. In addition, the strong association between long-term H. pylori infection and gastric cancer has raised more questions regarding the clinical significance of this organism. There is speculation that long-term H. pylori infection resulting in chronic gastritis is an important risk factor for gastric carcinoma resulting in H. pylori being classified as a carcinogen.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      7
      Seconds
  • Question 13 - You evaluate a 80-year-old man who has a history of persistent heart failure...

    Correct

    • You evaluate a 80-year-old man who has a history of persistent heart failure and discover that he has generalised oedema.

      Which of the following claims regarding capillary hydrostatic pressure (P c) is false?

      Your Answer: P c increases along the length of the capillary, from arteriole to venule

      Explanation:

      The capillary hydrostatic pressure (Pc) is normally between 15 and 30 millimetres of mercury. Pc Decreases along the capillary’s length, mirroring the arteriolar and venule pressures proximally and distally.
      Pc is determined by the ratio of arteriolar resistance (RA) to venular resistance (RV).

      When the RA/RV ratio is high, the pressure drop across the capillary is modest, and Pcis is close to venule pressure.

      When the ratio of RA/RV is low, the pressure drop across the capillary is considerable, and Pcis is close to arteriolar pressure.

      Pcis closer to the venule pressure and thus more responsive to changes in venous pressure than arteriolar pressure when RA/RV is high.

      Pcis the major force behind fluid pushing out of the capillary bed and into the interstitium.
      It is also the most variable of the forces affecting fluid transport at the capillary, partly because sympathetic-mediated arteriolar vasoconstriction varies.

    • This question is part of the following fields:

      • Cardiovascular Physiology
      • Physiology
      28.7
      Seconds
  • Question 14 - A 30-year-old male with a known allergy to natural latex rubber presents with...

    Correct

    • A 30-year-old male with a known allergy to natural latex rubber presents with an allergic reaction to a food he has just eaten.

      Which ONE of these foods is most likely to cause an associated hypersensitivity in him?

      Your Answer: Banana

      Explanation:

      About one third of patients with allergy to natural latex rubber (NRL) have an associated allergy to some plant-derived foods. It is known as the latex-fruit syndrome and occurs commonly with consumption of fresh fruits. Banana and avocado are the most implicated fruits but it can also be seen with tomato, kiwi and chestnut.

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      10.2
      Seconds
  • Question 15 - Regarding ciprofloxacin, which of the following statements is INCORRECT: ...

    Correct

    • Regarding ciprofloxacin, which of the following statements is INCORRECT:

      Your Answer: Ciprofloxacin decreases plasma concentrations of theophylline.

      Explanation:

      Ciprofloxacin increases plasma concentrations of theophylline. There is an increased risk of convulsions when quinolones are given with NSAIDs or theophylline. There is an increased risk of tendon damage when quinolones are given with corticosteroids. Quinolones are known to increase the QT-interval and should not be taken with concomitantly with other drugs that are known to cause QT-interval prolongation. There is an increased risk of myopathy when erythromycin or clarithromycin are taken with simvastatin or atorvastatin.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      18.5
      Seconds
  • Question 16 - You are teaching a group of medical students about cardiovascular examination. You are...

    Correct

    • You are teaching a group of medical students about cardiovascular examination. You are discussing heart sounds and the cardiac cycle. Which of the following stages of the cardiac cycle occurs immediately after the aortic valve closes:

      Your Answer: Isovolumetric relaxation

      Explanation:

      Immediately after the closure of the semilunar valves, the ventricles rapidly relax and ventricular pressure decreases rapidly but the AV valves remain closed as initially the ventricular pressure is still greater than atrial pressure. This is isovolumetric relaxation. Atrial pressure continues to rise because of venous return, with the v wave of the JVP waveform peaking during this phase. Rapid flow of blood from the atria into the ventricles during the ventricular filling phase causes thethird heart sound, which is normal in children but, in adults, is associated with disease such as ventricular dilation.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      12.7
      Seconds
  • Question 17 - A 39-year-old woman's son with meningococcal meningitis was recently admitted to the Paediatric...

    Correct

    • A 39-year-old woman's son with meningococcal meningitis was recently admitted to the Paediatric Intensive Care Unit. She is currently 22 weeks pregnant and is concerned about the possibility of her also contracting the disease as she cared closely for her son during his admission.

      Which antibiotic would be the MOST appropriate choice for chemoprophylaxis in this case?

      Your Answer: Ciprofloxacin

      Explanation:

      Ciprofloxacin is recommended for use as meningococcal chemoprophylaxis in all age groups and in pregnancy, and is the most appropriate for this patient.

      However, rifampicin is the drug of choice for meningococcal chemoprophylaxis because it is licensed for chemoprophylaxis, but multiple doses are necessary and it is not readily available in community pharmacies. It also interacts with oral contraceptives.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      14.2
      Seconds
  • Question 18 - Which of these statements about the monospot test is true? ...

    Correct

    • Which of these statements about the monospot test is true?

      Your Answer: It can be positive in rubella

      Explanation:

      Infectious mononucleosis can be diagnosed using specific EBV antibodies and a variety of unrelated non-EBV heterophile antibodies.

      Heterophile antibodies:
      About 70-90% of patients with EBV infectious mononucleosis produce antibodies against an antigen produced in one species that react against antigens from other species called heterophile antibodies. False positives can be seen with rubella, hepatitis, SLE, malaria, toxoplasmosis, lymphoma and leukaemia.

      These antibodies can be detected by two main screening tests:
      The monospot test uses horse red blood cells. It agglutinates in the presence of heterophile antibodies.
      Paul-Bunnell test uses sheep red blood cells. The blood agglutinates in the presence of heterophile antibodies.

      EBV-specific antibodies:
      Patients can remain heterophile-negative after six weeks and are then considered to be heterophile-negative and should be tested for EBV-specific antibodies. EBV-specific antibodies test are helpful if a false positive heterophile antibody test is suspected.
      The indirect Coombs test is used to detect in-vitro antibody-antigen reactions. It is typically used in antenatal antibody screening and in preparation for blood transfusion.
      Heterophile antibody tests are generally not positive in the incubation period of infectious mononucleosis (4-6 weeks) before the onset of symptoms.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      6.3
      Seconds
  • Question 19 - A 67-year-old female presents with a history of morning stiffness and arthritis of...

    Correct

    • A 67-year-old female presents with a history of morning stiffness and arthritis of her hand joints. She is being investigated for rheumatoid arthritis.

      Which test is most sensitive and specific for this diagnosis?

      Your Answer: Anti-CCP

      Explanation:

      Anti-cyclic citrullinated peptide (anti-CCP) is an antibody present in 60-80% of rheumatoid arthritis patients. It is measured by enzyme-linked immunosorbent assay (ELISA). It may be present years before the onset of the disease and is associated with a more severe disease course.

      While most patients with anti-CCP antibodies are also positive for rheumatoid factor (RF), RF antibody is not specific for rheumatoid arthritis as it can occur in patients with other conditions such as infections and other autoimmune conditions.

      ESR, antinuclear antibodies(ANA) and Synovial fluid examination are not specific for rheumatoid arthritis.

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      35
      Seconds
  • Question 20 - A patient presents with a rash for dermatological examination. A large area of...

    Incorrect

    • A patient presents with a rash for dermatological examination. A large area of purplish discolouration of the skin that measures 2 cm in diameter and does not blanch when pressure is applied is seen .

      What is the best description of this rash that you have found on examination?

      Your Answer: Purpura

      Correct Answer: Ecchymoses

      Explanation:

      Ecchymosis are discolouration of the skin or mucous membranes caused by extravasation of blood. They are usually red or purple in colour and measure greater than 1 cm in diameter and do not blanch on applying pressure.

      A macule is a flat, well circumscribed area of discoloured skin less than 1 cm in diameter with no changes in the thickness or texture of the skin.

      Petechiae are discolouration of the skin measuring less than 3 mm in diameter

      Purpura are discolouration of the skin measuring between 0.3 cm and 1 cm in diameter.

      Erythema is redness of the skin or mucous membranes caused by hyperaemia of superficial capillaries caused by skin injury, infection or inflammation. Erythema blanches when pressure is applied whereas ecchymosis, purpura and petechiae do not.

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      61.8
      Seconds
  • Question 21 - When treating diabetic ketoacidosis (DKA), glucose should be given together with insulin as...

    Correct

    • When treating diabetic ketoacidosis (DKA), glucose should be given together with insulin as soon as the blood glucose concentration falls below 14 mmol/L in the form of:

      Your Answer: 10% glucose intravenous infusion at a rate of 125 mL/hour

      Explanation:

      In addition to the sodium chloride 0.9 percent infusion, glucose 10% should be given intravenously (into a large vein with a large-gauge needle) at a rate of 125 mL/hour once blood glucose concentration falls below 14 mmol/litre.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      27.1
      Seconds
  • Question 22 - Which of the following microbes attaches to host cells by its haemagglutinin antigen:...

    Correct

    • Which of the following microbes attaches to host cells by its haemagglutinin antigen:

      Your Answer: Influenza virus

      Explanation:

      Hemagglutinin (HA) or Haemagglutinin (BE) is an antigenic glycoprotein found on the surface of the influenza viruses. It is responsible for binding the virus to the cell that is being infected. The name hemagglutinin comes from the protein’s ability to cause red blood cells (erythrocytes) to clump together (agglutinate) in vitro.

    • This question is part of the following fields:

      • Microbiology
      • Principles
      12.2
      Seconds
  • Question 23 - One of the benefits of wound healing through first intention is: ...

    Correct

    • One of the benefits of wound healing through first intention is:

      Your Answer: Minimisation of scar tissue formation

      Explanation:

      Primary wound healing, or healing by first intention, occurs within hours of repairing a full-thickness surgical incision. This surgical insult results in the mortality of a minimal number of cellular constituents. Healing by first intention can occur when the wound edges are opposed, the wound is clean and uninfected and there is minimal loss of cells and tissue i.e. surgical incision wound. The wound margins are joined by fibrin deposition, which is subsequently replaced by collagen and covered by epidermal growth.

    • This question is part of the following fields:

      • Pathology
      • Wound Healing
      60.3
      Seconds
  • Question 24 - Regarding V/Q mismatch, which of the following statements is CORRECT: ...

    Correct

    • Regarding V/Q mismatch, which of the following statements is CORRECT:

      Your Answer: In a true shunt, increasing inspired oxygen has no effect on improving hypoxaemia.

      Explanation:

      Both ventilation and perfusion increase towards the lung base, because of the effects of gravity, but the gravitational effects are greater on perfusion than ventilation and therefore there is a regional variation in V/Q ratio from lung apex (high V/Q) to lung base (low V/Q). In a pure shunt, there is normal perfusion but absent ventilation and the V/Q ratio = 0. In a true shunt increasing oxygen fraction has no effect because the oxygen-enriched air fails to reach the shunted blood. An increased A-a gradient is seen in V/Q mismatch.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      107.3
      Seconds
  • Question 25 - All of the muscles of the tongue (other than the palatoglossus) are innervated...

    Correct

    • All of the muscles of the tongue (other than the palatoglossus) are innervated by which of the following nerves:

      Your Answer: Hypoglossal nerve

      Explanation:

      All of the muscles of the tongue are innervated by the hypoglossal nerve, except for the palatoglossus, which is innervated by the vagus nerve.

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
      53.5
      Seconds
  • Question 26 - During anaerobic respiration, what is the net generation of ATP molecules: ...

    Incorrect

    • During anaerobic respiration, what is the net generation of ATP molecules:

      Your Answer: 4

      Correct Answer: 2

      Explanation:

      In anaerobic respiration, two ATP molecules are produced for every glucose molecule, as opposed to the 38 molecules of ATP produced in aerobic respiration.

    • This question is part of the following fields:

      • Basic Cellular
      • Physiology
      20.1
      Seconds
  • Question 27 - The following statements concerning lung compliance is true EXCEPT?
    ...

    Correct

    • The following statements concerning lung compliance is true EXCEPT?

      Your Answer: Lung compliance is described by the equation: C = ∆ P/ ∆V, where C = compliance, P = pressure, and V = volume

      Explanation:

      Lung compliance is the change in volume per unit change in distending pressure.

      It is calculated using the equation:
      Lung compliance = ΔV / ΔP
      Where:
      ΔV is the change in volume
      ΔP is the change in pleural pressure.

      Lung compliance is inversely proportional to stiffness and elastance.

      It comprises static (no airflow) and dynamic (during continuous breathing) components.

      It is the slope of the pressure-volume curve.

      Lung compliance describes the distensibility of the lungs and the chest wall.

    • This question is part of the following fields:

      • Physiology
      • Respiratory Physiology
      20.7
      Seconds
  • Question 28 - A 20-year-old boy took almost 25 tablets of paracetamol almost 4 hours ago....

    Incorrect

    • A 20-year-old boy took almost 25 tablets of paracetamol almost 4 hours ago. The boy is healthy and has no known comorbid or drug history.

      Out of the following metabolic pathways, which one is primarily responsible for the toxic effects of paracetamol?

      Your Answer: Glucuronidation

      Correct Answer: N-hydroxylation

      Explanation:

      Paracetamol is predominantly metabolized in the liver by three main metabolic pathways:
      1. Glucuronidation (45-55%)
      2. Sulphate conjugation (30-35%)
      3. N-hydroxylation via the hepatic cytochrome P450 enzyme system (10-15%)

      Cytochrome P450 enzymes catalyse the oxidation of acetaminophen to the reactive metabolite N-acetyl-p-benzoquinoneimine (NAPQI). NAPQI primarily contributes to the toxic effects of acetaminophen. NAPQI is an intermediate metabolite that is further metabolized by fast conjugation with glutathione. The conjugated metabolite is then excreted in the urine as mercapturic acid. High doses of acetaminophen (overdoses) can lead to hepatic necrosis due to depleting glutathione and high binding levels of reactive metabolite (NAPQI) to important parts of liver cells.

    • This question is part of the following fields:

      • CNS Pharmacology
      • Pharmacology
      56.2
      Seconds
  • Question 29 - Which of the following is the most common cause of megaloblastic anaemia: ...

    Correct

    • Which of the following is the most common cause of megaloblastic anaemia:

      Your Answer: Vitamin B12 deficiency

      Explanation:

      Megaloblastic anemia results from inhibition of DNA synthesis during red blood cell production. When DNA synthesis is impaired, the cell cycle cannot progress from the growth stage to the mitosis stage. This leads to continuing cell growth without division, which presents as macrocytosis, with an increase in mean corpuscular volume (MCV). The defect in red cell DNA synthesis is most often due to hypovitaminosis, specifically vitamin B12 deficiency or folate deficiency.
      Folate is an essential vitamin found in most foods, especially liver, green vegetables and yeast. The normal daily diet contains 200 – 250 μg, of which about 50% is absorbed. Daily adult requirements are about 100 μg. Absorption of folate is principally from the duodenum and jejunum. Stores of folate are normally only adequate for 4 months and so features of deficiency may be apparent after this time.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      14.1
      Seconds
  • Question 30 - A 72 year old man is brought to ED by ambulance with sudden...

    Correct

    • A 72 year old man is brought to ED by ambulance with sudden onset chest pain, palpitations and shortness of breath. His HR is 160 bpm and BP 90/65. ECG demonstrates new-onset fast atrial fibrillation. Which of the following is the first-line treatment option in this case:

      Your Answer: Synchronised DC cardioversion

      Explanation:

      All patients with adverse features suggesting life-threatening haemodynamic instability (shock, syncope, heart failure, myocardial ischaemia) caused by new onset atrial fibrillation should undergo emergency electrical cardioversion with synchronised DC shock without delaying to achieve anticoagulation.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      28.5
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Cardiovascular (4/4) 100%
Pharmacology (5/6) 83%
Anatomy (5/5) 100%
Head And Neck (3/3) 100%
General Pathology (4/5) 80%
Pathology (7/8) 88%
Physiology (5/6) 83%
Inflammatory Responses (1/1) 100%
Central Nervous System (2/2) 100%
Immunological Products & Vaccines (1/1) 100%
Microbiology (5/5) 100%
Pathogens (1/1) 100%
Specific Pathogen Groups (3/3) 100%
Cardiovascular Physiology (1/1) 100%
Infections (1/1) 100%
Endocrine (1/1) 100%
Principles (1/1) 100%
Wound Healing (1/1) 100%
Respiratory (1/1) 100%
Basic Cellular (0/1) 0%
Respiratory Physiology (1/1) 100%
CNS Pharmacology (0/1) 0%
Haematology (1/1) 100%
Passmed