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  • Question 1 - A 36-year-old woman is suspected to have a postpartum haemorrhage a few hours...

    Incorrect

    • A 36-year-old woman is suspected to have a postpartum haemorrhage a few hours after delivery. Conservative and medical measures fail to stop the bleeding, resulting in a loss of over 2000mls of blood. The woman is urgently taken to the operating room.

      During the procedure, the consultant obstetrician attempts to perform an internal iliac artery ligation. This artery is significant as it gives rise to several smaller vessels that supply nearby structures.

      Which of the following correctly identifies a pair of arteries that branch off the internal iliac artery?

      Your Answer: Inferior epigastric and cremasteric artery

      Correct Answer: Superior and inferior vesical arteries

      Explanation:

      The branches of the internal iliac artery can be easily remembered using the mnemonic I Love Going Places In My Very Own Soiled Underwear! These branches include the iliolumbar artery, lateral sacral artery, superior and inferior gluteal arteries, internal pudendal artery, inferior vesical (or uterine in females) artery, middle rectal artery, vaginal artery, obturator artery, and umbilical artery. On the other hand, the external iliac artery gives rise to the inferior epigastric, cremasteric, and deep circumflex arteries.

      Bladder Anatomy and Innervation

      The bladder is a three-sided pyramid-shaped organ located in the pelvic cavity. Its apex points towards the symphysis pubis, while the base lies anterior to the rectum or vagina. The bladder’s inferior aspect is retroperitoneal, while the superior aspect is covered by peritoneum. The trigone, the least mobile part of the bladder, contains the ureteric orifices and internal urethral orifice. The bladder’s blood supply comes from the superior and inferior vesical arteries, while venous drainage occurs through the vesicoprostatic or vesicouterine venous plexus. Lymphatic drainage occurs mainly to the external iliac and internal iliac nodes, with the obturator nodes also playing a role. The bladder is innervated by parasympathetic nerve fibers from the pelvic splanchnic nerves and sympathetic nerve fibers from L1 and L2 via the hypogastric nerve plexuses. The parasympathetic fibers cause detrusor muscle contraction, while the sympathetic fibers innervate the trigone muscle. The external urethral sphincter is under conscious control, and voiding occurs when the rate of neuronal firing to the detrusor muscle increases.

    • This question is part of the following fields:

      • Renal System
      50.3
      Seconds
  • Question 2 - A 28-year-old female, who is 5 months postpartum, presents with a 4-week history...

    Incorrect

    • A 28-year-old female, who is 5 months postpartum, presents with a 4-week history of weight loss, heat intolerance, tremor, palpitation and diarrhoea. Pregnancy and birth were uncomplicated. On further questioning, she admits having taken off-license weight loss medication bought from the internet 2 months ago. Past medical history and family history are insignificant. She does not smoke or drink alcohol.

      On physical examination, she has exophthalmos, brisk reflexes and fine tremor. Her vital signs were heart rate 100/minute, blood pressure 138/78 mmHg, temperature 36.6ºC. The thyroid gland was diffusely enlarged.

      Thyroid Stimulating Hormone (TSH) 0.01 mU/l
      Free thyroxine (T4) 25 pmol/l
      Total thyroxine (T4) 155 nmol/l

      What is the most likely diagnosis?

      Your Answer: De Quervain's thyroiditis

      Correct Answer: Graves' Disease

      Explanation:

      During the postnatal period, Graves’ disease may either present for the first time or worsen. Exophthalmos is a distinctive symptom of Graves’ disease that is not observed in other hyperthyroid conditions. Hypothyroidism is caused by Hashimoto’s thyroiditis. postpartum thyroiditis is characterized by initial hyperthyroidism after childbirth, followed by normal or occasionally reduced thyroid levels.

      During pregnancy, there is an increase in the levels of thyroxine-binding globulin (TBG), which causes an increase in the levels of total thyroxine. However, this does not affect the free thyroxine level. If left untreated, thyrotoxicosis can increase the risk of fetal loss, maternal heart failure, and premature labor. Graves’ disease is the most common cause of thyrotoxicosis during pregnancy, but transient gestational hyperthyroidism can also occur due to the activation of the TSH receptor by HCG. Propylthiouracil has traditionally been the antithyroid drug of choice, but it is associated with an increased risk of severe hepatic injury. Therefore, NICE Clinical Knowledge Summaries recommend using propylthiouracil in the first trimester and switching to carbimazole in the second trimester. Maternal free thyroxine levels should be kept in the upper third of the normal reference range to avoid fetal hypothyroidism. Thyrotropin receptor stimulating antibodies should be checked at 30-36 weeks gestation to determine the risk of neonatal thyroid problems. Block-and-replace regimes should not be used in pregnancy, and radioiodine therapy is contraindicated.

      On the other hand, thyroxine is safe during pregnancy, and serum thyroid-stimulating hormone should be measured in each trimester and 6-8 weeks postpartum. Women require an increased dose of thyroxine during pregnancy, up to 50% as early as 4-6 weeks of pregnancy. Breastfeeding is safe while on thyroxine. It is important to manage thyroid problems during pregnancy to ensure the health of both the mother and the baby.

    • This question is part of the following fields:

      • Endocrine System
      57.8
      Seconds
  • Question 3 - A 29-year-old man with a prolonged history of alcoholism is brought to the...

    Incorrect

    • A 29-year-old man with a prolonged history of alcoholism is brought to the emergency department after experiencing a prolonged seizure. Despite a thorough examination, no underlying causes of seizures are found. The attending consultant suspects that the seizure may be due to a deficiency in which vitamin, as a result of the patient's chronic alcohol consumption?

      Your Answer: Vitamin B3

      Correct Answer: Vitamin B6

      Explanation:

      The Importance of Vitamin B6 in the Body

      Vitamin B6 is a type of water-soluble vitamin that belongs to the B complex group. Once it enters the body, it is converted into pyridoxal phosphate (PLP), which acts as a cofactor for various biochemical reactions such as transamination, deamination, and decarboxylation. These reactions are essential for the proper functioning of the body.

      However, a deficiency in vitamin B6 can lead to various health problems such as peripheral neuropathy and sideroblastic anemia. One of the common causes of vitamin B6 deficiency is isoniazid therapy, which is used to treat tuberculosis. Therefore, it is important to ensure that the body receives an adequate amount of vitamin B6 to maintain optimal health.

    • This question is part of the following fields:

      • General Principles
      13
      Seconds
  • Question 4 - A 26-year-old patient is hospitalized for pneumonia and undergoes a rapid HIV screen,...

    Incorrect

    • A 26-year-old patient is hospitalized for pneumonia and undergoes a rapid HIV screen, which returns positive. Upon discharge, the patient is referred to an HIV clinic and prescribed a regimen of antiretroviral therapy, including raltegravir. What is the mechanism of action of this drug?

      Your Answer: Prevents HIV from entering and infecting immune cells

      Correct Answer: Prevents viral genome from being inserted into host DNA

      Explanation:

      Integrase inhibitors, also known as ‘gravirs’, prevent the insertion of the viral genome into the DNA of the host cell by blocking the action of the enzyme integrase. Raltegravir is an example of an integrase inhibitor. The ‘gr’ in the names of these drugs may help to remember ‘inteGRase inhibitor’. This mode of action is different from nucleoside reverse transcriptase inhibitors (NRTIs), which act as chain-terminators to stop reverse transcription, non-nucleoside reverse transcriptase inhibitors (NNRTIs), which block the action of reverse transcriptase, and protease inhibitor drugs, which block the action of viral proteases. Entry inhibitor drugs, such as maraviroc and enfuvirtide, prevent HIV from entering cells by binding to CCR5 and GP41, respectively.

      Antiretroviral therapy (ART) is a treatment for HIV that involves a combination of at least three drugs. This combination typically includes two nucleoside reverse transcriptase inhibitors (NRTI) and either a protease inhibitor (PI) or a non-nucleoside reverse transcriptase inhibitor (NNRTI). ART reduces viral replication and the risk of viral resistance emerging. The 2015 BHIVA guidelines recommend that patients start ART as soon as they are diagnosed with HIV, rather than waiting until a particular CD4 count.

      Entry inhibitors, such as maraviroc and enfuvirtide, prevent HIV-1 from entering and infecting immune cells. Nucleoside analogue reverse transcriptase inhibitors (NRTI), such as zidovudine, abacavir, and tenofovir, can cause peripheral neuropathy and other side effects. Non-nucleoside reverse transcriptase inhibitors (NNRTI), such as nevirapine and efavirenz, can cause P450 enzyme interaction and rashes. Protease inhibitors (PI), such as indinavir and ritonavir, can cause diabetes, hyperlipidaemia, and other side effects. Integrase inhibitors, such as raltegravir and dolutegravir, block the action of integrase, a viral enzyme that inserts the viral genome into the DNA of the host cell.

    • This question is part of the following fields:

      • General Principles
      33.4
      Seconds
  • Question 5 - A randomised controlled trial compares two drugs used in the initial management of...

    Incorrect

    • A randomised controlled trial compares two drugs used in the initial management of hypertension in elderly patients. After being assigned to the randomised groups, a number of patients drop out due to adverse effects of the medication. How should the data be analysed?

      Your Answer: Remove patients who drop out from final data set

      Correct Answer: Include the patients who drop out in the final data set

      Explanation:

      Understanding Intention to Treat Analysis

      Intention to treat analysis is a statistical method used in randomized controlled trials. It involves analyzing all patients who were randomly assigned to a particular treatment group, regardless of whether they completed or received the treatment. This approach is used to avoid the effects of crossover and drop-out, which can affect the randomization of patients to treatment groups.

      In simpler terms, intention to treat analysis is a way of analyzing data from a clinical trial that ensures all patients are included in the analysis, regardless of whether they completed the treatment or not. This approach is important because it helps to avoid bias that may arise from patients dropping out of the study or switching to a different treatment group. By analyzing all patients as originally assigned, researchers can get a more accurate picture of the effectiveness of the treatment being studied.

    • This question is part of the following fields:

      • General Principles
      20.9
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  • Question 6 - A 48-year-old man is brought into the emergency department after attempting to take...

    Correct

    • A 48-year-old man is brought into the emergency department after attempting to take his own life. He was found at home with empty packets of paracetamol by his side. He is still conscious. A history is taken from him to evaluate his risk of future attempts.

      What is the most significant risk factor for a successful suicide?

      Your Answer: Addiction to opiates

      Explanation:

      Individuals with a history of alcohol or drug abuse and deliberate self harm, particularly males, should be considered at high risk for suicide.

      The risk of suicide in psychiatric patients is often stratified into high, medium, or low risk categories, but there is limited evidence on the positive predictive value of individual risk factors. A review in the BMJ concluded that these assessments may not be useful in guiding decision making, as 50% of suicides occur in patients deemed low risk. However, certain factors have been associated with an increased risk of suicide, such as male sex, history of deliberate self-harm, alcohol or drug misuse, mental illness, depression, schizophrenia, chronic disease, advancing age, unemployment or social isolation, and being unmarried, divorced, or widowed.

      If a patient has attempted suicide, there are additional factors that increase the risk of completed suicide in the future, such as efforts to avoid discovery, planning, leaving a written note, final acts such as sorting out finances, and using a violent method. On the other hand, there are protective factors that can reduce the risk of suicide, such as having family support, having children at home, and having a religious belief.

    • This question is part of the following fields:

      • Psychiatry
      14.8
      Seconds
  • Question 7 - Which one of the following statements relating to the pancreas is not true?...

    Correct

    • Which one of the following statements relating to the pancreas is not true?

      Your Answer: Cholecystokinin causes relaxation of the gallbladder

      Explanation:

      The contraction of the gallbladder is caused by CCK.

      The gallbladder is a sac made of fibromuscular tissue that can hold up to 50 ml of fluid. Its lining is made up of columnar epithelium. The gallbladder is located in close proximity to various organs, including the liver, transverse colon, and the first part of the duodenum. It is covered by peritoneum and is situated between the right lobe and quadrate lobe of the liver. The gallbladder receives its arterial supply from the cystic artery, which is a branch of the right hepatic artery. Its venous drainage is directly to the liver, and its lymphatic drainage is through Lund’s node. The gallbladder is innervated by both sympathetic and parasympathetic nerves. The common bile duct originates from the confluence of the cystic and common hepatic ducts and is located in the hepatobiliary triangle, which is bordered by the common hepatic duct, cystic duct, and the inferior edge of the liver. The cystic artery is also found within this triangle.

    • This question is part of the following fields:

      • Gastrointestinal System
      36.5
      Seconds
  • Question 8 - A 25-year-old woman presents for her first-trimester review at the antenatal clinic. She...

    Incorrect

    • A 25-year-old woman presents for her first-trimester review at the antenatal clinic. She reports feeling well with no specific concerns. Due to complications in her previous pregnancy, she undergoes several screening blood tests, including thyroid function testing. The results reveal a TSH level of 4.2 mIU/L (normal range: 0.4-4.0), thyroxine (T4) level of 220 nmol/L (normal range: 64-155), and free thyroxine (fT4) level of 15 pmol/L (normal range: 12.0-21.9). Despite having no symptoms of thyrotoxicosis and a normal physical examination, what thyroid-associated protein primarily causes these findings to occur?

      Your Answer: Thyroglobulin

      Correct Answer: Thyroid binding globulin

      Explanation:

      During pregnancy, thyroid function can be affected, leading to a range of conditions. However, in the case of a patient with a nodular goitre, antithyroid antibodies are not a likely cause. Thyroglobulin levels may increase slightly in the final trimester, but this is not the primary issue. Similarly, while TSH levels may be raised in pregnancy, this is a secondary effect caused by an increase in TBG.

      During pregnancy, there is an increase in the levels of thyroxine-binding globulin (TBG), which causes an increase in the levels of total thyroxine. However, this does not affect the free thyroxine level. If left untreated, thyrotoxicosis can increase the risk of fetal loss, maternal heart failure, and premature labor. Graves’ disease is the most common cause of thyrotoxicosis during pregnancy, but transient gestational hyperthyroidism can also occur due to the activation of the TSH receptor by HCG. Propylthiouracil has traditionally been the antithyroid drug of choice, but it is associated with an increased risk of severe hepatic injury. Therefore, NICE Clinical Knowledge Summaries recommend using propylthiouracil in the first trimester and switching to carbimazole in the second trimester. Maternal free thyroxine levels should be kept in the upper third of the normal reference range to avoid fetal hypothyroidism. Thyrotropin receptor stimulating antibodies should be checked at 30-36 weeks gestation to determine the risk of neonatal thyroid problems. Block-and-replace regimes should not be used in pregnancy, and radioiodine therapy is contraindicated.

      On the other hand, thyroxine is safe during pregnancy, and serum thyroid-stimulating hormone should be measured in each trimester and 6-8 weeks postpartum. Women require an increased dose of thyroxine during pregnancy, up to 50% as early as 4-6 weeks of pregnancy. Breastfeeding is safe while on thyroxine. It is important to manage thyroid problems during pregnancy to ensure the health of both the mother and the baby.

    • This question is part of the following fields:

      • Endocrine System
      33.9
      Seconds
  • Question 9 - A 31-year-old woman is brought to the emergency department after collapsing at home,...

    Incorrect

    • A 31-year-old woman is brought to the emergency department after collapsing at home, witnessed by her partner while walking in the garden. She has a medical history of vascular Ehlers-Danlos syndrome. On examination, she is unresponsive with a Glasgow Coma Score of 3. A non-contrast CT head shows no pathology, but an MRI brain reveals a basilar artery dissection. What is the probable outcome of this patient's presentation?

      Your Answer: Wallenberg syndrome

      Correct Answer: Locked-in syndrome

      Explanation:

      The correct answer is locked-in syndrome, which is characterized by the paralysis of all voluntary muscles except for those controlling eye movements, while cognitive function remains preserved. Lesions in the basilar artery can cause quadriplegia and bulbar palsies as it supplies the pons, which transmits the corticospinal tracts.

      While brainstem lesions can cause Horner’s syndrome, it is typically caused by involvement of the hypothalamus, which is supplied by the circle of Willis. Therefore, Horner’s syndrome is not typically caused by basilar artery lesions.

      Medial medullary syndrome can be caused by lesions of the anterior spinal artery and is characterized by contralateral hemiplegia, altered sensorium, and deviation of the tongue toward the affected side.

      Wallenberg syndrome can be caused by lesions of the posterior inferior cerebellar artery (PICA) and presents with dysphagia, ataxia, vertigo, and contralateral deficits in temperature and pain sensation.

      Stroke can affect different parts of the brain depending on which artery is affected. If the anterior cerebral artery is affected, the person may experience weakness and loss of sensation on the opposite side of the body, with the lower extremities being more affected than the upper. If the middle cerebral artery is affected, the person may experience weakness and loss of sensation on the opposite side of the body, with the upper extremities being more affected than the lower. They may also experience vision loss and difficulty with language. If the posterior cerebral artery is affected, the person may experience vision loss and difficulty recognizing objects.

      Lacunar strokes are a type of stroke that are strongly associated with hypertension. They typically present with isolated weakness or loss of sensation on one side of the body, or weakness with difficulty coordinating movements. They often occur in the basal ganglia, thalamus, or internal capsule.

    • This question is part of the following fields:

      • Neurological System
      16.8
      Seconds
  • Question 10 - A nulliparous woman visits her obstetrician at 28 weeks of pregnancy. She has...

    Correct

    • A nulliparous woman visits her obstetrician at 28 weeks of pregnancy. She has a history of asthma and has noticed a deterioration in her asthma symptoms over the past few days. She is concerned that her asthma may affect her unborn child, as she has read online about the presence of extra antibodies in her blood due to asthma. Which immunoglobulin can be transmitted to her baby?

      Your Answer: IgG

      Explanation:

      The immunoglobulin that fixes complement and is able to pass to the fetal circulation is IgG. This immunoglobulin is produced by plasma cells and is present in all body fluids, being the most abundant in the body. IgG is the only immunoglobulin that can provide immunity to a fetus by crossing the placenta. It indirectly promotes phagocytosis through complement activation. To remember this, you can associate the letter G with gestation.

      On the other hand, IgA is the predominant immunoglobulin found in breast milk and in the secretions of digestive, respiratory, and urogenital tracts and systems. However, it does not transmit to the fetus during pregnancy.

      IgD does not pass into the fetal circulation and is poorly understood. It is found on naive B cells and is involved in B cell activation, which in turn activates mast cell release. Mast cells produce antimicrobial factors involved in immune defense.

      Finally, IgE is involved in asthma and allergic reactions, as well as in protecting against parasitic worms and other allergens. It acts by binding to the allergen, activating mast cells and basophils. However, it does not pass into the fetal circulation.

      Immunoglobulins, also known as antibodies, are proteins produced by the immune system to help fight off infections and diseases. There are five types of immunoglobulins found in the body, each with their own unique characteristics.

      IgG is the most abundant type of immunoglobulin in blood serum and plays a crucial role in enhancing phagocytosis of bacteria and viruses. It also fixes complement and can be passed to the fetal circulation.

      IgA is the most commonly produced immunoglobulin in the body and is found in the secretions of digestive, respiratory, and urogenital tracts and systems. It provides localized protection on mucous membranes and is transported across the interior of the cell via transcytosis.

      IgM is the first immunoglobulin to be secreted in response to an infection and fixes complement, but does not pass to the fetal circulation. It is also responsible for producing anti-A, B blood antibodies.

      IgD’s role in the immune system is largely unknown, but it is involved in the activation of B cells.

      IgE is the least abundant type of immunoglobulin in blood serum and is responsible for mediating type 1 hypersensitivity reactions. It provides immunity to parasites such as helminths and binds to Fc receptors found on the surface of mast cells and basophils.

    • This question is part of the following fields:

      • General Principles
      25.5
      Seconds
  • Question 11 - A 60-year-old patient visits the renal clinic after being diagnosed with stage 4...

    Incorrect

    • A 60-year-old patient visits the renal clinic after being diagnosed with stage 4 chronic kidney disease due to hypertension and diabetes. She inquires about the recommended diet for her condition.

      What dietary advice should be provided to the patient?

      Your Answer: High protein, low sodium

      Correct Answer: Low protein, phosphate, potassium and sodium

      Explanation:

      For individuals with chronic kidney disease, it is recommended to follow a diet that is low in protein, phosphate, potassium, and sodium. This is because protein can produce ammonia, which is not effectively excreted by the kidneys in CKD. Phosphate can combine with calcium to form kidney stones, while sodium can raise blood pressure and further damage the kidneys. Potassium is also not efficiently eliminated by failing kidneys and can lead to irregular heartbeats.

      Dietary Recommendations for Chronic Kidney Disease Patients

      Chronic kidney disease patients are recommended to follow a specific diet that is low in protein, phosphate, sodium, and potassium. This dietary advice is given to reduce the strain on the kidneys, as these substances are typically excreted by the kidneys. By limiting the intake of these nutrients, patients can help slow the progression of their kidney disease and manage their symptoms more effectively. It is important for patients to work closely with their healthcare provider or a registered dietitian to ensure they are meeting their nutritional needs while following these dietary restrictions. With proper guidance and adherence to this diet, patients with chronic kidney disease can improve their overall health and quality of life.

    • This question is part of the following fields:

      • Renal System
      25.4
      Seconds
  • Question 12 - A 9-year-old girl is brought to the emergency department with acute onset pain...

    Incorrect

    • A 9-year-old girl is brought to the emergency department with acute onset pain in her hands for the past 2 hours. She has a history of recurrent infections. Physical examination shows tender diffuse swelling of her hands bilaterally.

      Her blood tests show:
      Hb 85 g/L Male: (119-150)
      Female: (119-150)
      Platelets 250 * 109/L (150 - 400)
      WBC 6 * 109/L (4.0 - 11.0)
      Mean corpuscular volume (MCV) 90 fL (80-100)

      Peripheral smear examination shows numerous sickled red blood cells (RBC) and Howell-jolly bodies. Haemoglobin electrophoresis confirms sickle cell disease.

      Which of the following is a beneficial prophylactic drug for her?

      Your Answer: Erythropoietin

      Correct Answer: Hydroxyurea

      Explanation:

      Hydroxyurea is utilized in the prophylactic management of sickle cell anemia to prevent painful episodes by increasing the levels of HbF. The management of sickle cell disease involves two aspects: acute episodes and chronic management. Acute episodes are treated with adequate hydration and effective analgesia, while chronic management aims to prevent acute episodes and treat complications. Hydroxyurea has been proven to reduce the frequency of painful crises and the need for blood transfusions by increasing HbF levels, which has a higher affinity for oxygen than haemoglobin A. Acetaminophen is an analgesic that inhibits the cyclooxygenase enzyme and is only useful in mild pain cases. Methotrexate is a chemotherapeutic agent that has no role in sickle cell disease management.

      Managing Sickle-Cell Anaemia

      Sickle-cell anaemia is a genetic blood disorder that causes red blood cells to become misshapen and break down, leading to a range of complications. When a crisis occurs, management involves providing analgesia, rehydration, oxygen, and potentially antibiotics if there is evidence of infection. Blood transfusions may also be necessary, and in some cases, an exchange transfusion may be required if there are neurological complications.

      In the longer term, prophylactic management of sickle-cell anaemia involves the use of hydroxyurea, which increases the levels of HbF to prevent painful episodes. Additionally, it is recommended that sickle-cell patients receive the pneumococcal polysaccharide vaccine every five years to reduce the risk of infection. By implementing these management strategies, individuals with sickle-cell anaemia can better manage their condition and improve their quality of life.

    • This question is part of the following fields:

      • Haematology And Oncology
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      Seconds
  • Question 13 - What is the primary cell-cell interaction necessary for the development of granulomas? ...

    Incorrect

    • What is the primary cell-cell interaction necessary for the development of granulomas?

      Your Answer: NK cells and macrophages

      Correct Answer: Th1 CD4+ T cell and macrophages

      Explanation:

      The Formation of Granulomas

      Granulomas are formed when bacteria that cannot be killed are ingested by macrophages. These macrophages, which are filled with resistant bacteria such as Mycobacterium tuberculosis or Mycobacterium leprae, receive assistance from Th1 CD4+ T cells in the form of IFN-gamma. The macrophage then releases IL-12 to maintain its association with the T cell, and IFN-gamma helps activate the macrophage’s killing mechanisms. However, if this fails to clear the bacteria, the response moves to a more protective role. Fibroblasts seal off the area, forming a capsule that may become calcified. In TB infection, it is common for the macrophages within to undergo necrosis.

      FDC and B cells interact to produce high-affinity antibody, while NK cells and macrophages do not directly interact with any particular response. Th2 CD4+ T cells provide stimulatory signals to B cells for the production of antibody. Th2 CD4+ T cells and CD8+ T cells do not directly interact for any specific response. Th1 CD4+ cells are part of the antiviral response, along with CD8+ T cells.

    • This question is part of the following fields:

      • Clinical Sciences
      39.5
      Seconds
  • Question 14 - At which of the following anatomical locations does the common peroneal nerve bifurcate...

    Incorrect

    • At which of the following anatomical locations does the common peroneal nerve bifurcate into the superficial and deep peroneal nerves?

      Your Answer: Within the substance of tibialis anterior muscle

      Correct Answer: At the lateral aspect of the neck of the fibula

      Explanation:

      The point where the common peroneal nerve is most susceptible to injury is at the neck of the fibula, where it divides into two branches.

      The common peroneal nerve originates from the dorsal divisions of the sacral plexus, specifically from L4, L5, S1, and S2. This nerve provides sensation to the skin and fascia of the anterolateral surface of the leg and dorsum of the foot, as well as innervating the muscles of the anterior and peroneal compartments of the leg, extensor digitorum brevis, and the knee, ankle, and foot joints. It is located laterally within the sciatic nerve and passes through the lateral and proximal part of the popliteal fossa, under the cover of biceps femoris and its tendon, to reach the posterior aspect of the fibular head. The common peroneal nerve divides into the deep and superficial peroneal nerves at the point where it winds around the lateral surface of the neck of the fibula in the body of peroneus longus, approximately 2 cm distal to the apex of the head of the fibula. It is palpable posterior to the head of the fibula. The nerve has several branches, including the nerve to the short head of biceps, articular branch (knee), lateral cutaneous nerve of the calf, and superficial and deep peroneal nerves at the neck of the fibula.

    • This question is part of the following fields:

      • Neurological System
      32.6
      Seconds
  • Question 15 - A 16-year-old boy has been diagnosed with aplastic anaemia. He hails from a...

    Correct

    • A 16-year-old boy has been diagnosed with aplastic anaemia. He hails from a family of farmers and used to play hide and seek in the barns where pesticides and other chemicals were stored. He visited his GP complaining of fatigue, dyspnoea, and headaches. Further blood tests revealed a significant leucopenia. Aplastic anaemia is a condition where haematopoietic stem cells that produce immune cell precursors fail. Where in the body are these cells primarily located?

      Your Answer: Bone marrow

      Explanation:

      Aplastic anemia is a condition where there is a shortage of blood cells from all types of progenitor lines. It is most commonly seen in individuals between the ages of 15 to 25 and those over 60.

      The causes of aplastic anemia can be attributed to various factors such as infections (including Epstein-Barr), toxic exposure (such as benzene and radiation), idiopathic, and rarely hereditary.

      Haematopoietic stem cells in the bone marrow generate immune cells. These cells produce two main types of progenitors, myeloid and lymphoid progenitor cells, which give rise to all immune cells.

      Myeloid progenitor cells give rise to cells such as macrophages/monocytes, dendritic cells, neutrophils, eosinophils, basophils, and mast cells. On the other hand, lymphoid progenitor cells give rise to T cells, NK cells, B cells, and dendritic cells.

      Aplastic anaemia is a condition characterized by a decrease in the number of blood cells due to a poorly functioning bone marrow. It is most commonly seen in individuals around the age of 30 and is marked by a reduction in red blood cells, white blood cells, and platelets. While lymphocytes may be relatively spared, the overall effect is a condition known as pancytopenia. In some cases, aplastic anaemia may be the first sign of acute lymphoblastic or myeloid leukaemia. A small number of patients may later develop paroxysmal nocturnal haemoglobinuria or myelodysplasia.

      The causes of aplastic anaemia can be idiopathic, meaning that they are unknown, or they can be linked to congenital conditions such as Fanconi anaemia or dyskeratosis congenita. Certain drugs, such as cytotoxics, chloramphenicol, sulphonamides, phenytoin, and gold, as well as toxins like benzene, can also cause aplastic anaemia. Infections such as parvovirus and hepatitis, as well as exposure to radiation, can also contribute to the development of this condition.

    • This question is part of the following fields:

      • Haematology And Oncology
      36.6
      Seconds
  • Question 16 - What is the virus being studied by the researchers that is fatal if...

    Incorrect

    • What is the virus being studied by the researchers that is fatal if contracted by pregnant women and affects erythrocyte progenitors and endothelial cells, leading to severe anaemia and potential heart failure, ultimately resulting in fetal loss or accumulation of fluid in the serous cavities of the fetus?

      Your Answer: Poxvirus

      Correct Answer: Parvovirus

      Explanation:

      Parvovirus B19 is the correct answer for the virus described in the vignette. This virus is the smallest DNA virus and the only single-stranded DNA virus. Infections during pregnancy can be fatal for the baby, as the virus suppresses fetal erythropoiesis, leading to severe anaemia and heart failure, ultimately resulting in hydrops fetalis. In children, infections cause erythema infectiosum or fifth disease, which presents with a characteristic ‘slapped cheek’ appearance.

      Ancylostoma duodenale is not the correct answer, as it is a roundworm/nematode, not a virus. Although infections with this parasite can cause microcytic anaemia as the worm sucks blood from the intestinal wall.

      Herpes simplex virus-1 (HSV-1) is also not the correct answer, as it is an enveloped, double-stranded virus, unlike parvovirus. Infections with HSV-1 cause gingivostomatitis, herpetic whitlow, and temporal lobe encephalitis. The virus can also remain latent in the trigeminal ganglia.

      Human herpesvirus-8 (HHV-8) is also not the correct answer, as it is an enveloped, double-stranded virus, unlike parvovirus. Infections with HHV-8 are mainly seen in patients with HIV/AIDS or post-transplant patients, causing a neoplasm of endothelial cells known as Kaposi sarcoma.

      Parvovirus B19: A Virus with Various Clinical Presentations

      Parvovirus B19 is a type of DNA virus that can cause different clinical presentations. One of the most common is erythema infectiosum, also known as fifth disease or slapped-cheek syndrome. This illness may manifest as a mild feverish condition or a noticeable rash that appears after a few days. The rash is characterized by rose-red cheeks, which is why it is called slapped-cheek syndrome. It may spread to other parts of the body but rarely involves the palms and soles. The rash usually peaks after a week and then fades, but it may recur for some months after exposure to triggers such as warm baths, sunlight, heat, or fever. Most children recover without specific treatment, and school exclusion is unnecessary as the child is no longer infectious once the rash emerges. However, in adults, the virus may cause acute arthritis.

      Aside from erythema infectiosum, parvovirus B19 can also present as asymptomatic, pancytopenia in immunosuppressed patients, or aplastic crises in sickle-cell disease. The virus suppresses erythropoiesis for about a week, so aplastic anemia is rare unless there is a chronic hemolytic anemia. In pregnant women, the virus can cross the placenta and cause severe anemia due to viral suppression of fetal erythropoiesis, which may lead to heart failure secondary to severe anemia and the accumulation of fluid in fetal serous cavities such as ascites, pleural and pericardial effusions. This condition is called hydrops fetalis and is treated with intrauterine blood transfusions.

      It is important to note that parvovirus B19 can affect an unborn baby in the first 20 weeks of pregnancy. If a woman is exposed early in pregnancy, she should seek prompt advice from her antenatal care provider as maternal IgM and IgG will need to be checked. The virus is spread by the respiratory route, and a person is infectious 3 to 5 days before the appearance of the rash. Children are no longer infectious once the rash appears, and there is no specific treatment. Therefore, school exclusion is unnecessary.

    • This question is part of the following fields:

      • General Principles
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  • Question 17 - Which interleukin is accountable for the growth of B cells? ...

    Correct

    • Which interleukin is accountable for the growth of B cells?

      Your Answer: IL-4

      Explanation:

      The proliferation and differentiation of B cells is attributed to IL-4. Macrophages produce IL-1, an acute inflammatory protein. T cell proliferation is encouraged by IL-2. Myeloid cells undergo proliferation and differentiation due to IL-3.

      Overview of Cytokines and Their Functions

      Cytokines are signaling molecules that play a crucial role in the immune system. Interleukins are a type of cytokine that are produced by various immune cells and have specific functions. IL-1, produced by macrophages, induces acute inflammation and fever. IL-2, produced by Th1 cells, stimulates the growth and differentiation of T cell responses. IL-3, produced by activated T helper cells, stimulates the differentiation and proliferation of myeloid progenitor cells. IL-4, produced by Th2 cells, stimulates the proliferation and differentiation of B cells. IL-5, also produced by Th2 cells, stimulates the production of eosinophils. IL-6, produced by macrophages and Th2 cells, stimulates the differentiation of B cells and induces fever. IL-8, produced by macrophages, promotes neutrophil chemotaxis. IL-10, produced by Th2 cells, inhibits Th1 cytokine production and is known as an anti-inflammatory cytokine. IL-12, produced by dendritic cells, macrophages, and B cells, activates NK cells and stimulates the differentiation of naive T cells into Th1 cells.

      In addition to interleukins, there are other cytokines with specific functions. Tumor necrosis factor-alpha, produced by macrophages, induces fever and promotes neutrophil chemotaxis. Interferon-gamma, produced by Th1 cells, activates macrophages. Understanding the functions of cytokines is important in developing treatments for various immune-related diseases.

    • This question is part of the following fields:

      • General Principles
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  • Question 18 - A 28-year-old woman with autosomal dominant polycystic kidney disease type 1 is seeking...

    Correct

    • A 28-year-old woman with autosomal dominant polycystic kidney disease type 1 is seeking guidance from her general practitioner regarding family planning. She recently lost her father to a subarachnoid haemorrhage, which prompted her to undergo genetic testing to confirm her diagnosis. Despite her desire to start a family with her husband, she is worried about the possibility of passing on the renal disease to her children. On which chromosome is the genetic defect for this condition most commonly found?

      Your Answer: Chromosome 16

      Explanation:

      The patient’s autosomal dominant polycystic kidney disease type 1 is not caused by a gene on chromosomes 13, 18, or 21. It is important to note that nondisjunction of these chromosomes can lead to other genetic disorders such as Patau syndrome, Edward’s syndrome, and Down’s syndrome. The chance of the patient passing on the autosomal dominant polycystic kidney disease type 1 to her children would depend on the inheritance pattern of the specific gene mutation causing the disease.

      Autosomal dominant polycystic kidney disease (ADPKD) is a commonly inherited kidney disease that affects 1 in 1,000 Caucasians. The disease is caused by mutations in two genes, PKD1 and PKD2, which produce polycystin-1 and polycystin-2 respectively. ADPKD type 1 accounts for 85% of cases, while ADPKD type 2 accounts for 15% of cases. ADPKD type 1 is caused by a mutation in the PKD1 gene on chromosome 16, while ADPKD type 2 is caused by a mutation in the PKD2 gene on chromosome 4. ADPKD type 1 tends to present with renal failure earlier than ADPKD type 2.

      To screen for ADPKD in relatives of affected individuals, an abdominal ultrasound is recommended. The diagnostic criteria for ultrasound include the presence of two cysts, either unilateral or bilateral, if the individual is under 30 years old. If the individual is between 30-59 years old, two cysts in both kidneys are required for diagnosis. If the individual is over 60 years old, four cysts in both kidneys are necessary for diagnosis.

      For some patients with ADPKD, tolvaptan, a vasopressin receptor 2 antagonist, may be an option to slow the progression of cyst development and renal insufficiency. However, NICE recommends tolvaptan only for adults with ADPKD who have chronic kidney disease stage 2 or 3 at the start of treatment, evidence of rapidly progressing disease, and if the company provides it with the agreed discount in the patient access scheme.

    • This question is part of the following fields:

      • Renal System
      17.7
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  • Question 19 - A 65-year-old man with a medical history of obesity, hypertension, type 2 diabetes...

    Incorrect

    • A 65-year-old man with a medical history of obesity, hypertension, type 2 diabetes mellitus, and ischaemic heart disease is hospitalized for SARS-CoV-2 infection. He is started on oxygen therapy and a 10-day course of oral dexamethasone. What is the most crucial monitoring strategy following the initiation of this medication?

      Your Answer: Daily lying and standing blood pressure measurement

      Correct Answer: Four times daily capillary blood glucose

      Explanation:

      Regular monitoring of capillary blood glucose is recommended when using corticosteroids as they can worsen diabetic control due to their anti-insulin effects. Dexamethasone, a corticosteroid with a high glucocorticoid effect, carries a high risk of hyperglycaemia in patients with or without diabetes. Monitoring blood sugars is essential for patients with diabetes who are started on glucocorticoids. Monitoring cardiac function, daily amylase levels, daily lying and standing blood pressure, and daily urea and electrolytes are not routinely recommended while on corticosteroids. However, these tests may be necessary if suggestive symptoms develop.

      Corticosteroids are commonly prescribed medications that can be taken orally or intravenously, or applied topically. They mimic the effects of natural steroids in the body and can be used to replace or supplement them. However, the use of corticosteroids is limited by their numerous side effects, which are more common with prolonged and systemic use. These side effects can affect various systems in the body, including the endocrine, musculoskeletal, gastrointestinal, ophthalmic, and psychiatric systems. Some of the most common side effects include impaired glucose regulation, weight gain, osteoporosis, and increased susceptibility to infections. Patients on long-term corticosteroids should have their doses adjusted during intercurrent illness, and the medication should not be abruptly withdrawn to avoid an Addisonian crisis. Gradual withdrawal is recommended for patients who have received high doses or prolonged treatment.

    • This question is part of the following fields:

      • Endocrine System
      18.9
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  • Question 20 - A juvenile with cystic fibrosis also experiences malabsorption. What are some potential conditions...

    Incorrect

    • A juvenile with cystic fibrosis also experiences malabsorption. What are some potential conditions and outcomes for this individual?

      Your Answer: Vitamin B12 deficiency and neuropathy

      Correct Answer: Vitamin A deficiency and night blindness

      Explanation:

      Patients with cystic fibrosis experience a decrease in lipase secretion due to impaired pancreatic exocrine function, leading to inadequate absorption of fat-soluble vitamins such as A, D, E, and K. One of the symptoms of vitamin A deficiency is night blindness. However, this scenario would not cause vitamin B12 deficiency or excess vitamin A. Vitamin D deficiency can result in osteomalacia, while vitamin K deficiency can lead to coagulopathy.

      Vitamin A, also known as retinol, is a type of fat soluble vitamin that plays several important roles in the body. One of its key functions is being converted into retinal, which is a crucial visual pigment. Additionally, vitamin A is essential for proper epithelial cell differentiation and acts as an antioxidant to protect cells from damage.

      When the body lacks sufficient vitamin A, it can lead to a condition known as night blindness. This is because retinal is necessary for the eyes to adjust to low light conditions, and a deficiency can impair this process. Therefore, it is important to ensure adequate intake of vitamin A through a balanced diet or supplements to maintain optimal health.

    • This question is part of the following fields:

      • General Principles
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  • Question 21 - A 27-year-old woman from a rural town in Central America delivers a baby...

    Incorrect

    • A 27-year-old woman from a rural town in Central America delivers a baby at 37 weeks' gestation without any antenatal care. She had fallen ill during early pregnancy after consuming undercooked meat and received treatment with antibiotics from a local doctor. The neonatologist sent the baby's serum for PCR analysis, which revealed the presence of Toxoplasmosis gondii DNA. What are the probable clinical manifestations in this newborn?

      Your Answer: Periventricular calcifications, chorioretinitis, sensorineural hearing loss

      Correct Answer: Chorioretinitis, intracranial calcifications, hydrocephalus

      Explanation:

      The presence of congenital toxoplasmosis was confirmed by the PCR test on the baby’s serum. This condition is characterized by the classic triad of chorioretinitis, intracranial calcifications, and hydrocephalus.

      In contrast, congenital rubella syndrome is identified by the triad of cataracts, cochlear defects, and cardiac defects. Meanwhile, maculopapular rashes on the hands and soles are indicative of congenital syphilis, while periventricular calcifications, chorioretinitis, and sensorineural hearing loss are associated with congenital CMV infection.

      Congenital Toxoplasmosis: Effects on Neurological and Ophthalmic Health

      Congenital toxoplasmosis is a condition that occurs when a pregnant woman passes the Toxoplasma gondii parasite to her unborn child. This can result in a range of health issues, particularly affecting the neurological and ophthalmic systems.

      Neurological damage is a common feature of congenital toxoplasmosis, with cerebral calcification and hydrocephalus being two potential outcomes. Cerebral calcification refers to the buildup of calcium deposits in the brain, which can lead to seizures, developmental delays, and other neurological problems. Hydrocephalus, on the other hand, is a condition in which there is an excess of cerebrospinal fluid in the brain, causing pressure and potentially leading to brain damage.

      In addition to neurological damage, congenital toxoplasmosis can also cause ophthalmic damage. Chorioretinitis, a condition in which the retina becomes inflamed, is a common outcome. This can lead to vision loss and other eye-related problems. Retinopathy and cataracts are also potential effects of congenital toxoplasmosis.

      Overall, congenital toxoplasmosis can have significant impacts on a child’s health, particularly in terms of neurological and ophthalmic function. Early detection and treatment are crucial for minimizing the potential long-term effects of this condition.

    • This question is part of the following fields:

      • General Principles
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  • Question 22 - A 25-year-old graduate student is brought to the emergency department after he refused...

    Incorrect

    • A 25-year-old graduate student is brought to the emergency department after he refused to leave his apartment for the past three weeks. His roommate tried to convince him but he has been insisting that the government is monitoring his every move. In the emergency department, he refused to cooperate with the attending doctor but later agrees to talk to one of the nurses. He says that the government has implanted a device into his brain so that they can wirelessly control his thoughts and actions. He has been feeling that way for the past 10 months but during the last three weeks, he refused to leave his apartment as he believes the government agents are watching him through his computer. What is the primary neurotransmitter affected in this patient's condition?

      Your Answer: Nucleus accumbens

      Correct Answer: Ventral tegmentum

      Explanation:

      The individual exhibited indications of psychosis, including delusions and auditory hallucinations, which have persisted for over six months, indicating a potential diagnosis of schizophrenia. The patient’s delusion involved a steadfast belief that their brain could be manipulated wirelessly, which is considered a delusion due to its inconsistency with the individual’s cultural, social, and educational background. Schizophrenia primarily affects the neurotransmitter dopamine, which is synthesized in the brain’s primary source.

      Understanding Dopamine: Its Production, Effects, and Role in Diseases

      Dopamine is a neurotransmitter that is produced in the substantia nigra pars compacta, a region in the brain that is responsible for movement control. It plays a crucial role in regulating various bodily functions, including movement, motivation, and reward. Dopamine is also associated with feelings of pleasure and satisfaction, which is why it is often referred to as the feel-good neurotransmitter.

      However, dopamine levels can be affected by certain diseases. For instance, patients with schizophrenia have increased levels of dopamine, which can lead to symptoms such as hallucinations and delusions. On the other hand, patients with Parkinson’s disease have depleted levels of dopamine in the substantia nigra, which can cause movement problems such as tremors and rigidity.

      Aside from its effects on the brain, dopamine also has an impact on the kidneys. It causes renal vasodilation, which means that it widens the blood vessels in the kidneys, leading to increased blood flow and improved kidney function.

      In summary, dopamine is a vital neurotransmitter that affects various bodily functions. Its production and effects are closely linked to certain diseases, and understanding its role can help in the development of treatments for these conditions.

    • This question is part of the following fields:

      • General Principles
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  • Question 23 - Which Korotkoff sound indicates that the diastolic pressure has been reached during blood...

    Incorrect

    • Which Korotkoff sound indicates that the diastolic pressure has been reached during blood pressure measurement?

      Your Answer: Fourth

      Correct Answer: Fifth

      Explanation:

      Korotkoff Sounds

      Korotkoff sounds are the sounds heard when taking blood pressure readings. There are five phases of Korotkoff sounds, each indicating different stages of blood pressure. The first phase is a tapping sound, which indicates the systolic pressure. The second phase is a swooshing sound or murmurs. The third phase is a crisp tapping sound, while the fourth phase is a muffled, blowing sound. The fifth and final phase is silence.

      Older textbooks used to state that the fourth Korotkoff sound indicate diastolic pressure, but now the fifth sound is used preferentially. To take a blood pressure reading, the cuff is inflated and then slowly reduced. The first tapping sound heard is the systolic pressure. The cuff is then further deflated until silence is heard, which indicates the diastolic pressure. Korotkoff sounds is important for accurate blood pressure readings and proper diagnosis and treatment of hypertension.

    • This question is part of the following fields:

      • Clinical Sciences
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  • Question 24 - A woman falls onto her neck and examination elicits signs of lateral medullary...

    Incorrect

    • A woman falls onto her neck and examination elicits signs of lateral medullary syndrome. Which description provides the correct findings?

      Your Answer: Ipsilateral loss of light tough proprioception and contra lateral loss of pain and temperature

      Correct Answer: Ipsilateral loss of pain and temperature in the face with dysphagia and ataxia and contra lateral loss in the body

      Explanation:

      The lateral medullary syndrome is characterized by damage to the structures in the lateral medulla, which is supplied by the posterior inferior cerebellar artery. This can result in various examination findings, including ataxia from damage to the inferior cerebellar peduncle, dysphagia from damage to the nucleus ambiguus, and ipsilateral loss of pain and temperature from the face due to damage to the spinal trigeminal nucleus. Additionally, there may be contralateral loss of pain and temperature in the body from damage to the lateral spinothalamic tract.

      In contrast, Brown-Sequard syndrome, which results from cord hemisection, is characterized by ipsilateral loss of light touch proprioception and contralateral loss of pain and temperature. Pontine stroke may present with hypertonia and contralateral neglect, while the triad of gait disturbance, urinary incontinence, and dementia is seen in normal pressure hydrocephalus. Medial medullary syndrome may present with ipsilateral tongue deviation, contralateral limb weakness, and contralateral loss of proprioception.

      Understanding Lateral Medullary Syndrome

      Lateral medullary syndrome, also referred to as Wallenberg’s syndrome, is a condition that arises when the posterior inferior cerebellar artery becomes blocked. This condition is characterized by a range of symptoms that affect both the cerebellum and brainstem. Cerebellar features of the syndrome include ataxia and nystagmus, while brainstem features include dysphagia, facial numbness, and cranial nerve palsy such as Horner’s. Additionally, patients may experience contralateral limb sensory loss. Understanding the symptoms of lateral medullary syndrome is crucial for prompt diagnosis and treatment.

    • This question is part of the following fields:

      • Neurological System
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  • Question 25 - A patient is being treated for a pneumonia. She is given 200 mg...

    Correct

    • A patient is being treated for a pneumonia. She is given 200 mg of an antibiotic. The concentration of the drug in her bloodstream is measured at 5 mg/L.

      What is the volume of distribution of this drug?

      Your Answer: 40 L

      Explanation:

      Volume of Distribution

      The volume of distribution is a measure of the volume required to achieve a specific concentration of a drug in the plasma. For instance, if 200 mg of a drug is administered and the concentration in the plasma is 5 mg/L, this is equivalent to dissolving the drug in 40 L of fluid. However, the volume of distribution varies depending on the drug’s properties, such as its affinity for proteins or fats. In general, a volume of distribution that is ten times greater than the average total plasma volume suggests that the drug is primarily bound to tissues or fat rather than being freely available in the plasma. This information is crucial when determining the appropriate loading doses for certain medications, particularly those used to treat epilepsy. To summarize, the volume of distribution is essential for optimizing drug dosing and ensuring effective treatment.

    • This question is part of the following fields:

      • Pharmacology
      15.5
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  • Question 26 - A 28-year-old surgical trainee (ST) is conducting a research study in orthopedics to...

    Incorrect

    • A 28-year-old surgical trainee (ST) is conducting a research study in orthopedics to investigate the effectiveness of a new pain relief medication compared to a placebo. The ST wants to ensure that the study has enough power to detect a significant difference between the two groups if one truly exists.

      What is the statistical parameter that the ST is attempting to optimize in the design of the study?

      Your Answer: Confidence interval

      Correct Answer: Power

      Explanation:

      Significance tests are used to determine the likelihood of a null hypothesis being true. The null hypothesis states that two treatments are equally effective, while the alternative hypothesis suggests that there is a difference between the two treatments. The p value is the probability of obtaining a result by chance that is at least as extreme as the observed result, assuming the null hypothesis is true. Two types of errors can occur during significance testing: type I, where the null hypothesis is rejected when it is true, and type II, where the null hypothesis is accepted when it is false. The power of a study is the probability of correctly rejecting the null hypothesis when it is false, and it can be increased by increasing the sample size.

    • This question is part of the following fields:

      • General Principles
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  • Question 27 - What is the name of the intercellular junctional mechanism that allows cells to...

    Correct

    • What is the name of the intercellular junctional mechanism that allows cells to be electrically connected?

      Your Answer: Gap junction

      Explanation:

      Cell Junctions: Types and Functions

      Gap junctions are found where two adjacent cell membranes meet, allowing for electrical communication between cells. Desmosomes are specialized proteins that help cells stick together, particularly in epithelial tissue. Tight junctions prevent water and solutes from leaking out of cells. Zonula adherens junctions are cell junctions that connect to the actin cytoskeleton. These different types of cell junctions play important roles in maintaining the structure and function of tissues in the body.

    • This question is part of the following fields:

      • Clinical Sciences
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  • Question 28 - A 23-year-old man gets into a brawl outside a nightclub and is stabbed...

    Correct

    • A 23-year-old man gets into a brawl outside a nightclub and is stabbed in the back, on the left side, about 3 cm below the 12th rib in the mid scapular line. Which structure is most likely to be injured first as a result of this incident?

      Your Answer: Left kidney

      Explanation:

      The most probable structure to be injured is the left kidney, which is situated in this area. The left adrenal and ureter are unlikely to be injured alone, while the spleen is located higher up.

      Anatomical Planes and Levels in the Human Body

      The human body can be divided into different planes and levels to aid in anatomical study and medical procedures. One such plane is the transpyloric plane, which runs horizontally through the body of L1 and intersects with various organs such as the pylorus of the stomach, left kidney hilum, and duodenojejunal flexure. Another way to identify planes is by using common level landmarks, such as the inferior mesenteric artery at L3 or the formation of the IVC at L5.

      In addition to planes and levels, there are also diaphragm apertures located at specific levels in the body. These include the vena cava at T8, the esophagus at T10, and the aortic hiatus at T12. By understanding these planes, levels, and apertures, medical professionals can better navigate the human body during procedures and accurately diagnose and treat various conditions.

    • This question is part of the following fields:

      • Neurological System
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  • Question 29 - A 32-year-old woman is brought to the emergency department by her partner after...

    Incorrect

    • A 32-year-old woman is brought to the emergency department by her partner after an altercation. She is discovered unconscious in their bedroom with multiple packets of aspirin nearby. Medical intervention is initiated.

      What is the underlying cause of this aspirin overdose?

      Your Answer: Decreased NAPQI production

      Correct Answer: Decreased ATP production

      Explanation:

      An overdose of aspirin is likely to be intentional and can result in a decrease in ATP production by inhibiting the electron transport chain in mitochondria. Aspirin and paracetamol are easily accessible medications that are commonly used. Inhibition of the electron transport chain in mitochondria due to aspirin overdose leads to a decrease in ATP production, increased oxygen consumption, increased carbon dioxide levels, and increased heat generation.

      Emergency medical treatment for aspirin overdose may include activated charcoal (if given within 1 hour of overdose), sodium bicarbonate (to enhance aspirin urinary excretion by making urine alkaline), and haemodialysis.

      The answer ‘Central nervous system depression’ is incorrect as it is the underlying mechanism in benzodiazepine overdose.

      The answer ‘Decreased NAPQI production’ is incorrect as NAPQI is the toxic metabolite produced in paracetamol overdose, and decreased levels of NAPQI are actually beneficial.

      The answer ‘Increased ATP production’ is incorrect as an aspirin overdose causes uncoupling of the electron transport chain, leading to a decrease in ATP production in the mitochondria.

      Salicylate overdose can cause a combination of respiratory alkalosis and metabolic acidosis. The respiratory center is initially stimulated, leading to hyperventilation and respiratory alkalosis. However, the direct acid effects of salicylates, combined with acute renal failure, can later cause metabolic acidosis. In children, metabolic acidosis tends to be more prominent. Other symptoms of salicylate overdose include tinnitus, lethargy, sweating, pyrexia, nausea/vomiting, hyperglycemia and hypoglycemia, seizures, and coma.

      The treatment for salicylate overdose involves general measures such as airway, breathing, and circulation support, as well as administering activated charcoal. Urinary alkalinization with intravenous sodium bicarbonate can help eliminate aspirin in the urine. In severe cases, hemodialysis may be necessary. Indications for hemodialysis include a serum concentration of over 700 mg/L, metabolic acidosis that is resistant to treatment, acute renal failure, pulmonary edema, seizures, and coma.

      Salicylates can also cause the uncoupling of oxidative phosphorylation, which leads to decreased adenosine triphosphate production, increased oxygen consumption, and increased carbon dioxide and heat production. It is important to recognize the symptoms of salicylate overdose and seek prompt medical attention to prevent serious complications.

    • This question is part of the following fields:

      • General Principles
      15.6
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  • Question 30 - A 35-year-old woman presents to her GP with a two-month history of tingling...

    Incorrect

    • A 35-year-old woman presents to her GP with a two-month history of tingling and numbness in her thumb, index and middle finger that wakes her up at night. During the examination, the GP instructs the patient to flex her wrist for 60 seconds and the patient reports that this reproduces the symptoms. What is the term for this test?

      Your Answer: Tinel's test

      Correct Answer: Phalen's test

      Explanation:

      Carpal tunnel syndrome is a condition that occurs when the median nerve in the carpal tunnel is compressed. This can cause pain and pins and needles sensations in the thumb, index, and middle fingers. In some cases, the symptoms may even travel up the arm. Patients may shake their hand to alleviate the discomfort, especially at night. During an examination, weakness in thumb abduction and wasting of the thenar eminence may be observed. Tapping on the affected area may also cause paraesthesia, and flexing the wrist can trigger symptoms.

      There are several potential causes of carpal tunnel syndrome, including idiopathic factors, pregnancy, oedema, lunate fractures, and rheumatoid arthritis. Electrophysiology tests may reveal prolongation of the action potential in both motor and sensory nerves. Treatment options may include a six-week trial of conservative measures such as wrist splints at night or corticosteroid injections. If symptoms persist or are severe, surgical decompression may be necessary, which involves dividing the flexor retinaculum.

    • This question is part of the following fields:

      • Musculoskeletal System And Skin
      12.4
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SESSION STATS - PERFORMANCE PER SPECIALTY

Renal System (1/3) 33%
Endocrine System (0/3) 0%
General Principles (2/11) 18%
Psychiatry (1/1) 100%
Gastrointestinal System (1/1) 100%
Neurological System (1/4) 25%
Haematology And Oncology (1/2) 50%
Clinical Sciences (1/3) 33%
Pharmacology (1/1) 100%
Musculoskeletal System And Skin (0/1) 0%
Passmed