Nokea
What is a hallmark of Type IV hypersensitivity?
- A. It is immediate and IgE-mediated
- B. It is delayed and T cell-mediated
- C. It involves immune complexes
- D. It stimulates mast cells to release histamine
Correct Answer: B
Rationale: The correct answer is B because Type IV hypersensitivity reactions are delayed and T cell-mediated. Upon exposure to an antigen, sensitized T cells, specifically CD4+ T cells, release cytokines that recruit and activate macrophages and other effector cells, leading to tissue damage. Choice A is incorrect because Type I hypersensitivity reactions are immediate and IgE-mediated. Choice C is incorrect because immune complex-mediated hypersensitivity reactions are typically associated with Type III hypersensitivity. Choice D is incorrect because histamine release by mast cells is characteristic of Type I hypersensitivity reactions, not Type IV.
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A patient who has received a kidney transplant has been admitted to the medical unit with acute rejection and is receiving IV cyclosporine (Sandimmune) and methylprednisolone (Solu-Medrol). Which staff member is best to assign to care for this patient?
- A. An RN who floated to the medical unit from the coronary care unit for the day.
- B. An RN with 3 years of experience in the operating room who is orienting to the medical unit.
- C. An RN who has worked on the medical unit for 5 years and is working a double shift today.
- D. A new graduate RN who needs experience with IV medication administration.
Correct Answer: C
Rationale: An experienced RN who is familiar with the medical unit and its protocols is the best choice for caring for a patient with acute rejection. This patient requires close monitoring and skilled care which an experienced RN can provide. The other options involve RNs who may not be as familiar with the unit or are less experienced.
Tropism is a phenomenon by which
- A. plants response to stimulation
- B. reducing lateral branching
- C. Affected by the length of the day and night
- D. All above
Correct Answer: A
Rationale: The correct answer is A: plants response to stimulation. Tropism refers to the growth or movement of an organism in response to a stimulus. Plants exhibit tropisms such as phototropism (response to light) and geotropism (response to gravity). This choice accurately defines the phenomenon.
Choice B is incorrect because reducing lateral branching is not a defining characteristic of tropism.
Choice C is incorrect because the length of day and night does not directly relate to tropism.
Choice D is incorrect because not all options listed are characteristics of tropism.
Which cell type is a sentinel in the tissues and part of the innate immune system?
- A. T lymphocytes
- B. Dendritic cells
- C. B lymphocytes
- D. Plasma cells
Correct Answer: B
Rationale: The correct answer is B: Dendritic cells. Dendritic cells are sentinel cells in tissues that detect pathogens and activate the immune response. They are crucial in initiating adaptive immune responses by presenting antigens to T cells. T lymphocytes (A) are involved in adaptive immunity, not innate immunity. B lymphocytes (C) mature into plasma cells (D) which produce antibodies, but they are not sentinel cells in tissues like dendritic cells.
What type of cells do natural killer (NK) cells target?
- A. Bacterial cells
- B. Virus-infected and cancerous cells
- C. Plasma cells
- D. Self-antigens
Correct Answer: B
Rationale: Natural killer (NK) cells target virus-infected and cancerous cells because they have the ability to recognize abnormal cells through activating receptors. These cells can identify changes in surface markers associated with viral infection or cancer, leading to their destruction. NK cells do not target bacterial cells (choice A), plasma cells (choice C), or self-antigens (choice D) as these are not typically recognized as threats by the immune system. NK cells play a crucial role in immune surveillance against abnormal cells, making choice B the correct answer.
The physician plans to prescribe trastuzumab (Herceptin) for the patient with breast cancer. What testing will the physician order before prescribing this medication?
- A. HER2 protein levels
- B. BRCA2 gene mutation
- C. BRCA1 gene mutation
- D. Stage II cancer identification
Correct Answer: A
Rationale: Trastuzumab targets HER2-positive breast cancers, so HER2 protein level testing is essential to determine eligibility.