1. The most likely cause for the consumptive coagulopathy found in thrombotic thrombocytopenic purpura (TTP) is [1]:

   A. Endothelial damage with exposure of tissue factor (Factor III)
   B. Formation of extremely large multimers of von Willebrand Factor
   C. Production of an abnormal integrin protein by platelets
   D. Synthesis of a pro-coagulant cytokine by activated T lymphocytes
   E. Spontaneous activation of Factor VII due to mutations in the protein coding region

2. The initiation of toxic shock syndrome by staphylococci and streptococci is related to [2]:

   A. The expression of lipopolysaccharide (LPS) on the bacterial surface
   B. Gram positive bacterial teichoic acids
   C. Bacterial superantigens which induce polyclonal T cell activation and cytokine release
   D. Direct stimulation of macrophages and dendritic cells to produce IL1ß
   E. Infiltration of the bone marrow and stimulation of early leukocyte precursors

3. Theophylline is believed to cause bronchodilation primarily through [3]:

   A. Interaction with adenosine receptors in the bronchial tree
   B. Inhibition of cyclic nucleotide phosphodiesterase
   C. Interaction with ß2-adrenergic receptors
   D. Inhibition of cholinergic bronchoconstrictive receptors
   E. Blockade of leukotriene synthesis

4. The pathogenesis of most cases of hypercalcemia of malignancy is [1]:

   A. Stimulation of parathyroid production of parathyroid hormone (PTH) by the neoplasm
   B. Enhancement of vitamin D metabolism
   C. Direct effects of the tumor on the catabolism of bone
   D. Stimulation of renal conversion of hydroxyvitamin D to dihydroxyvitamin D
   E. Production of parathyroid-hormone like peptide (PTHRP) by the neoplasm

5. The pathogenesis of congenital forms of the Long QT Syndrome is [5]:

   A. Interactions between macrolide drugs and certain antihistamines
   B. Inherited inactivating mutations in the magnesium channel
   C. Overdoses of Type III anti-arrhythmic agents
   D. Mutations that lead to increased Na+ channel or decreased K+ channel activities
   E. Mutations in the calcium transporter

6. An abnormal plasma sodium value is indicative of [6]:

   A. Hypovolemia
   B. A disorder of water homeostasis
   C. Hypervolemia
   D. Abnormal sodium-potassium ATPase activity
   E. Inadequate free water intake

7. Goodpasteur's (Pulmonary-Renal) Syndrome is caused by [7]:

   A. Production of abnormal light chain proteins by clonal pre-neoplastic B lymphocytes
   B. Antineutrophil cytoplasmic antibodies with perinuclear staining (pANCA)
   C. Antibodies against basement membrane type IV collagen
   D. Antibodies against hemidesmosomal proteins
   E. Oligoclonal activation of specific T lymphocytes by certain bacterial toxins

8. The induction of cardiac valvular disease in rheumatic fever is most likely due to [8]:

   A. Molecular mimicry of streptococcal M and other proteins and heart valve proteins leadingto formation of antibodies against cardiac tissue
   B. Polyclonal stimulation of B lymphocytes which produce large numbers of antibodies
   C. Direct stimulation of monocytes to become macrophages
   D. Bacteremia leading to endothelial release of IL1 and IL6 which are toxic to myocytes
   E. Direct toxic effects of streptococcal cell wall components on endomyocardium

9. The activity of all-trans retinoic acid in acute promyelocytic leukemia is due to [9]:

   A. Signalling through surface "death" receptors which inactivate cyclins
   B. Binding to the BCR-Abl fusion protein and induction of apoptosis in leukemic cells
   C. Stimulation of a T helper type 1 immune response against leukemic cells
   D. Suppression of differentiation of multipotent progenitor cells into leukemic cells
   E. Binding to the PML-RARa fusion protein and induction of apoptosis in leukemic cells

10. All of the following abnormalities have been observed in heart failure EXCEPT [10]:

    A. Reduced levels of circulating natriuretic peptides
    B. Increased circulating levels of angiotensin II
    C. Increased circulating levels of tumor necrosis factor alpha
    D. Elevated levels of aldosterone even in the presence of ACE inhibitor therapy
    E. Reduced sensitivity of cardiac cells to adrenergic stimulation

Answers

1. B
2. C
3. A
4. E
5. D
6. B
7. C
8. A
9. E
10. A