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  1. The production of ketoacids in diabetic ketoacidosis is due primarily to [1]:
    A. Conversion of glucose to ketones and then ketoacids
    B. Increased lipolysis due to the very low levels of insulin and elevations in glucagon
    C. Elevated glucagon levels stimulate lipid breakdown
    D. Overproduction of cholecystekinin which stimulates fat breakdown
    E. Dehydration and hyperglycemia stimulate hepatic ketone and ketoacid synthesis
  2. All of the following concerning homocysteine (HC) are true EXCEPT [2]:
    A. HC has direct toxic effects on endothelium
    B. HC levels are directly correlated with systemic levels of atherosclerosis
    C. Reduction of HC levels with increased folate levels reduces vascular events
    D. Homozygous homocystinuria can be managed with betaine, a choline derivative
    E. Nitric oxide or vitamins C and E can block or reverse some of the effects of HC
  3. The most likely defect leading to the cytopenias in the myelodysplastic syndromes is [3]:
    A. Reduced rate of hematopoietic cell division
    B. Immune mediated destruction of multipotent progenitor cells
    C. Evolution an abnormal neutrophil lineage clone in the bone marrow
    D. Failed development of early erythroblasts due to mutations in cytokine receptor genes
    E. Increased apoptosis leading to enhanced cell destruction
  4. Which ONE of the following statements is true concerning T lymphocytes [4] ?
    A. T cells, like B cells, can develop in the bone marrow without additional structures
    B. CD4+ T helper cells are stimulated primarily by antigen associated with Class I histocompatibility proteins
    C. Like B cells, T cells require only one activation signal through the antigen receptor for stimulation
    D. T helper type 1 lymphocytes secrete primarily interferon gamma which activates killer cells and macrophages
    E. Antigen-presenting cells such as dendritic cells and macrophages are only required to present antigen to T cells in order to activate the T cells
  5. Hyperpigmentation is found in some cases of Cushing's Disease and in most cases of primary adrenal insufficiency. In these diseases, hyperpigmentation is caused by [5]:
    A. Overproduction of pro-opiomelanocortin by the pituitary gland
    B. Overproduction of melanocyte stimulating hormone by the hypothalamus
    C. Lack of feedback inhibition by cortisol on the hyopthalamus and pituitary
    D. Stimulatory effects of adrenal androgens on melanocytes in the skin
    E. Increased levels of corticotropin releasing hormone (CRH) by the hypothalamus
  6. Concerning vascular disease, all of the following are true EXCEPT [6]:
    A. Most endogenous vasodilators are pro-atherogenic
    B. Endothelin 1 is one of the most potent vasoconstrictors
    C. Endothelium are normally anti-atherogenic
    D. Platelet activation and binding in areas of injured endothelium is an early event in the formation of an atherosclerotic plaque
    E. Levels of systemic inflammation are correlated with progression of atherosclerosis
  7. Wilson's Disease is an autosomal recessive condition caused by [7]:
    A. Ingestion of toxic amounts of copper from paints and other sources
    B. Homozygous deletion of the gene for ceruloplasmin, the copper carrier protein
    C. Mutations in a gene which is involved in processing transporting ceruloplasmin-copper complex
    D. Mutations in the receptor for copper on liver cells and neurons
    E. Mutations in the copper transporter in the biliary tree leading to failed excretion
    1. Gene mapped to chr 13q14.3 cloned
    2. Gene called ATP7B involved in copper excretion
    3. Copper is bound to serum protein ceruloplasmin, and complex is excreted
    4. Gene is involved in processing and transporting ceruloplasmin complex [5]
    5. A large number of mutations have been descripted; 60% have most common His1069Gln
  8. The majority of syndromes characterized by elevated eosinophils involve [8]:
    A. Stimulation of mast cells
    B. Increased production of IL-5, usually by T lymphocytes
    C. Increase in circulating eosinophil chemotactic factor released by endothelia
    D. Clonal evolution of growth-factor independent eosinophils
    E. Release of IL4 and other cytokines by IgE dependent B lymphocytes
  9. All of the following are true concerning hereditary hemochromatosis EXCEPT [9]:
    A. The condition has been linked to mutations in the HFE protein
    B. HFE protein is found in highest concentrations in duodenal enterocytes involved in iron absorption and transport
    C. HFE protein binds to transferrin and can block transferrin-transferrin receptor binding
    D. Abnormalities in the apical membrane transporter protein DMT-1 have been found
    E. HFE protein is directly responsible for iron absorption from the duodenal lumen
  10. Concerning depression, all of the statements are true EXCEPT [10]
    A. Neurotransmitter receptor insensitivity or resistance likely plays a role in depression
    B. Abnormalities of both the serotonin and norepinephrine systems have been docemented
    C. SSRIs such as fluoxetine (Prozac®) and sertraline (Zoloft®) function primarily by blocking the uptake of serotonin once it has been released into the synaptic cleft
    D. Pharmacologic agents work rapidly in depression by restoring serotonin levels to normal
    E. "Remodelling" of neuronal pathways is believed to be required for the major actions of the antidepressants as well as for electroconvulsive therapy (ECT)

Answers navigator

  1. B
  2. C
  3. E
  4. D (T cells require at least two signals for activation.)
  5. A
  6. A
  7. C
  8. B
  9. E
  10. D