CRL Quiz 2 2006

1

Which one of the following statements about oxygen-derived free radicals is incorrect?


  They are produced by activation of leukocytes.

  They are detoxified by reactions involving glutathione.

  They do not survive for sufficient time to induce lung tissue injury.

  They are produced during phagocytosis of both infectious and non-infectious material.

  They may react with leukocyte peroxidases to form hypochlorite (bleach).

2

Antigen presentation to T cells on first exposure to an inhaled foreign antigen usually occurs in which one of the following sites?


  The lung epithelium.

  Lymph nodes draining the lung.

  Germinal centres in the airway mucosa.

  Bronchus associated lymphoid tissue.

  Blood in the airway microcirculation.

3

Which one of the following statements regarding chronic obstructive pulmonary disease (COPD) is correct?


  The vital capacity is normal or increased because of gas trapping.

  A reduced FEV1 confirms that there is airflow obstruction.

  There is an accelerated rate of decline of FEV1 with age in smokers.

  The FEV1 is not influenced by the person’s height.

  Plotting elastic recoil against maximal flow is often used to assess lung function in COPD.

4

Which one or more of the following statements regarding pneumonia is/are correct?


  Colonisation of the upper airway by relatively benign organisms is normal and is considered a defence mechanism.

  Respiratory mucosal secretory IgG plays a specific role in keeping the lower respiratory tract sterile.

  If only 1 and 3 are correct.

  In severe pneumonia PaCO2 can be elevated.

  If only 2 and 4 are correct.

  Diffusion impairment is the usual mechanism causing hypoxaemia in pneumonia. Answer A. If only 1, 2, and 3 are correct.

  If only 4 is correct.

  If all are correct.

5

Which one or more of the following statements about the pulmonary circulation is/are correct?


  In emphysema, there is a reduction in the volume of the pulmonary capillary bed.

  A reduction in the volume of the pulmonary capillary bed increases the likelihood of pulmonary arterial hypertension, especially during exercise.

  If only 1 and 3 are correct.

  Pulmonary arterial hypertension can arise from situations such as left to right shunts, where there is a long-standing increase in pulmonary blood flow.

  If only 2 and 4 are correct.

  Pulmonary arterial hypertension causes pulmonary oedema because of increased pulmonary capillary hydrostatic pressure. Answer A. If only 1, 2, and 3 are correct.

  If only 4 is correct.

  If all are correct.

6

Which one of the following is correct? TH2 cytokines are thought to be important in asthma because they:


  Enhance production of proinflammatory interferon gamma (IFNgamma), a TH1 cytokine.

  Promote eosinophilic inflammation, mast cell growth and mucus (goblet) cell growth.

  Prevent viral exacerbations.

  Synergise with inhaled corticosteroids.

  Synergise with inhaled beta-2 adrenoceptor agonists.

7

Which one or more of the following statements regarding the electrocardiogram (ECG) is/are correct?


  The ECG can indicate the left ventricular size.

  The ECG can indicate the rate of conduction through the atrioventricular node.

  If only 1 and 3 are correct

  The ECG can indicate the conduction through the bundle branches.

  If only 2 and 4 are correct

  The ECG can indicate the rhythm of the cardiac pacemaker. Answer A. If only 1, 2 and 3 are correct

  If only 4 is correct

  If all are correct

8

Which one or more of the following statements regarding cardiac myocyte contraction is/are correct?


  Contraction is activated by a rise in cell calcium.

  Calcium is stored in the sarcoplasmic reticulum for release during contraction.

  If only 1 and 3 are correct

  Increased intracellular calcium causes the interaction between myosin and actin.

  If only 2 and 4 are correct

  Hormones such as adrenaline will reduce intracellular calcium. Answer A. If only 1, 2 and 3 are correct

  If only 4 is correct

  If all are correct

9

Which one of the following is the best measure of cardiac contractility?


  Serum calcium level.

  Mean arterial blood pressure.

  Ejection fraction.

  Pulmonary artery wedge pressure.

  Cardiac output.

10

Which one or more of the following statements regarding autonomic control of cardiac contractility is/are correct?


  Parasympathetic nerves innervate the sino-atrial and atrio-ventricular nodes but there is little innervation of the cardiac muscle.

  Stimulation of muscarinic receptors slows the rate of firing of the sino-atrial node.

  If only 1 and 3 are correct

  β-adrenoceptor antagonists cause a greater reduction in heart rate during exercise compared to at rest.

  If only 2 and 4 are correct

  Atropine has little or no effect on heart rate at rest. Answer A. If only 1, 2 and 3 are correct

  If only 4 is correct

  If all are correct

11

Concerning individuals with the obstructive sleep apnoea syndrome (OSAS), which one or more of the following statements is/are correct?


  Apnoeas occur because of impaired diaphragmatic function.

  Upper airway resistance is increased during sleep.

  If only 1 and 3 are correct

  Apnoeas are worst in prone, non-rem sleep.

  If only 2 and 4 are correct

  Severe OSAS can cause daytime ventilatory failure. Answer A. If only 1, 2 and 3 are correct

  If only 4 is correct

  If all are correct

12

Which one of the following promotes bronchodilation of the lower airways?


  Hypertonic saline.

  Histamine.

  Methacholine.

  Sympathetic stimulation.

  Cool dry air.

13

A 70 year old man who has been smoking one packet of cigarettes per day for fifty years, has shortness of breath with minimal exertion. Spirometry show a forced expiratory ratio of 0.4 with an FEV1 40 % of the predicted mean. What is the most likely mechanism for his dyspnoea?


  Inflammation of alveolar walls.

  Hypoxaemia.

  Hypercapnia.

  Small airway closure during expiration.

  Eosinophils infiltration of the airways.

14

In a person with asthma who has wheeze and dyspnoea several times per week, when exercising, which of the following is likely to be found?


  Methacholine would reduce the FEV1 by less than 20 % from baseline.

  Reduced vital capacity and a normal forced expiratory ratio on spiromtery.

  Peak flows remaining stable over time.

  A reduction in the carbon monoxide transfer factor.

  An increase in FEV1 of more than 15 % following inhaled salbutamol.

15

Anti-arrhythmic drugs may act through which one or more of the following mechanisms?


  Antagonism of β-adrenoceptors.

  Blockade of sodium channels.

  If only 1 and 3 are correct

  Blockade of calcium channels.

  If only 2 and 4 are correct

  Blockade of chloride channels. Answer A. If only 1, 2 and 3 are correct

  If only 4 is correct

  If all are correct