Nokea
The 'major histocompatibility complex' (MHC) proteins involved in antigen presentation to T cells were first noted during studies of:
- A. Innate immunity
- B. Allergy
- C. Transplantation
- D. Autoimmunity
Correct Answer: C
Rationale: The correct answer is C: Transplantation. MHC proteins play a crucial role in transplant rejection by presenting antigens to T cells, initiating an immune response against foreign tissues. This discovery was significant in understanding transplant immunology. Choices A, B, and D are incorrect because innate immunity involves nonspecific defense mechanisms, allergies are mediated by IgE antibodies, and autoimmunity involves the immune system attacking self-antigens, none of which directly relate to the discovery of MHC proteins in transplantation studies.
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The nurse is admitting a patient to the clinical unit from surgery. Being alert to potential fluid volume alterations, what assessment data will be important for the nurse to monitor to identify early changes in the patient’s postoperative fluid volume (select all that apply)?
- A. Intake and output
- B. Skin turgor
- C. Lung sounds
- D. Respiratory rate
Correct Answer: A
Rationale: Monitoring intake/output, skin turgor, lung sounds, and respiratory rate helps detect dehydration, edema, or fluid overload early after surgery.
Which of the following statement is incorrect
- A. Antigens in tissues can reach regional LN via afferent lymphatic vessels
- B. Migrating dendritic cells that have collected antigens in tissues enter the draining LN via HEV
- C. During an infection fever and other inflammatory signals induce increased blood flow to draining LN and increased chances for lymphocytes to migrate from blood into LN
- D. The thoracic duct returns most of the circulating lymphocytes back to blood
Correct Answer: B
Rationale: The correct answer is B because migrating dendritic cells do not enter the draining lymph node (LN) via high endothelial venules (HEV); instead, they enter through afferent lymphatic vessels. HEVs are specialized post-capillary venules in LN where lymphocytes enter from the bloodstream. Dendritic cells, carrying antigens from tissues, travel via afferent lymphatic vessels to reach the LN where they present antigens to lymphocytes. Option A is correct as antigens in tissues reach LN via afferent lymphatic vessels. Option C is correct as infection-induced signals can increase blood flow to LN, facilitating lymphocyte migration. Option D is incorrect because the thoracic duct returns lymph back to the bloodstream, not specifically lymphocytes.
What is the primary role of Helper T cells in the immune response?
- A. Killing infected host cells
- B. Producing antibodies
- C. Secreting cytokines to activate other immune cells
- D. Suppressing immune responses
Correct Answer: C
Rationale: Helper T cells primarily secrete cytokines to activate other immune cells. This is crucial for coordinating and amplifying the immune response. They do not kill infected host cells (A), as that is the role of cytotoxic T cells. Producing antibodies (B) is the function of B cells. Suppressing immune responses (D) is the role of regulatory T cells, not Helper T cells.
Which of the following is a clinical feature of Grave's disease?
- A. Pulmonary fibrosis
- B. Exophthalmos and goiter
- C. Skin vasculitis
- D. Eczematous reaction
Correct Answer: B
Rationale: The correct answer is B: Exophthalmos and goiter. In Grave's disease, there is an overproduction of thyroid hormones leading to hyperthyroidism. Exophthalmos (bulging eyes) and goiter (enlarged thyroid gland) are classic clinical features due to autoimmune stimulation of thyroid-stimulating hormone receptors. Pulmonary fibrosis (A) is not typically associated with Grave's disease. Skin vasculitis (C) and eczematous reaction (D) are also not commonly seen in Grave's disease.
The three antibiotic-resistant bacteria that are of most current concern in North America are ____________________, ____________________, and ____________________.
- A. Methicillin-resistant Staphylococcus aureus (MRSA)
- B. Carbapenem-resistant Enterobacteriaceae (CRE)
- C. Vancomycin-resistant Enterococcus (VRE)
- D. All of the above
Correct Answer: D
Rationale: The correct answer is all of the above. MRSA, CRE, and VRE are among the most concerning antibiotic-resistant bacteria in North America due to their prevalence and difficulty in treatment.