Nokea
You give an intradermal injection of allergen to a patient who is undergoing skin testing for allergies. A few minutes later,the patient complains about feeling anxious short of breath and dizzy. You notice that the patient has reddened blotches on the face and arms. All of these therapies are available on your emergency cart. Which action should you take first?
- A. Start oxygen at 4 L/min using a nasal cannula.
- B. Obtain IV access with a large-bore IV catheter.
- C. Administer epinephrine (Adrenalin) 0.3 mL subcutaneously.
- D. Give albuterol (Proventil) with a nebulizer.
Correct Answer: C
Rationale: The patient is showing signs of anaphylaxis,a life-threatening allergic reaction. The first priority is to administer epinephrine which acts quickly to reverse the symptoms by constricting blood vessels relaxing airway muscles and increasing heart rate. Oxygen and IV access are important but secondary to the immediate administration of epinephrine. Albuterol may be used for bronchospasm but is not the first-line treatment for anaphylaxis.
You may also like to solve these questions
What is NOT true about innate immunity?
- A. Innate cells are immediately active, do not need clonal amplification or differentiation
- B. Innate cells can respond better and faster at a second encounter with the same pathogen
- C. Innate receptors recognizing pathogens do not have a fine specificity but rather recognize structures broadly found in different microbes
- D. Innate receptors can also recognize modified-self
Correct Answer: B
Rationale: The correct answer is B because innate immune cells do not respond better and faster at a second encounter with the same pathogen. This is a characteristic of adaptive immunity, not innate immunity. During a second encounter, adaptive immune cells produce a faster and stronger response due to memory cells formed during the initial exposure. In contrast, innate immune cells do not have memory cells and their response remains the same upon repeated encounters. Choice A is correct as innate cells are immediately active and do not require clonal amplification or differentiation. Choice C is correct as innate receptors recognize broad structures on pathogens. Choice D is correct as innate receptors can recognize modified-self, such as in autoimmune diseases.
A naïve lymphocyte:
- A. Does not yet express antigen receptors
- B. Is not yet considered mature
- C. Has not yet been activated by antigen
- D. Is found only in primary lymphoid tissues
Correct Answer: C
Rationale: Step-by-step rationale:
1. Naïve lymphocytes have antigen receptors but have not been activated by antigen.
2. Activation is necessary for their differentiation into effector cells.
3. Naïve lymphocytes are considered mature as they have completed development.
4. They circulate in secondary lymphoid tissues, not just primary lymphoid tissues.
Summary:
Choice C is correct because naïve lymphocytes have antigen receptors but have not been activated by antigen. Choices A, B, and D are incorrect because naïve lymphocytes do express antigen receptors, are considered mature, and can be found in both primary and secondary lymphoid tissues.
Which of the following statements is incorrect?
- A. BLASTX searches protein databases
- B. BLASTX use translated nucleotide as the query sequence
- C. Both TBLASTX and TBLASTN translate query into 6 reading frames
- D. BLASTN searches protein databases
Correct Answer: D
Rationale: The correct answer is D because BLASTN searches nucleotide databases, not protein databases. BLASTN uses a nucleotide sequence as the query to find similar sequences in nucleotide databases. This is different from BLASTX, which searches protein databases using translated nucleotide sequences (answer A is correct). TBLASTX and TBLASTN translate the query sequence into six reading frames to search for similarities in both nucleotide and protein databases (answer C is correct). BLASTN is specifically designed for nucleotide sequence searches, making statement D incorrect.
Which molecule released by NK cells is responsible for inducing apoptosis?
- A. Perforin
- B. Granzyme
- C. Cytokines
- D. Antibodies
Correct Answer: B
Rationale: The correct answer is B: Granzyme. Granzyme is the molecule released by NK cells that induces apoptosis in target cells. It enters the target cell through perforin, which creates pores in the target cell membrane. Cytokines are signaling molecules released by various immune cells but do not directly induce apoptosis. Antibodies are produced by B cells and do not induce apoptosis. Perforin aids in the delivery of granzyme but is not responsible for inducing apoptosis itself. Therefore, Granzyme is the correct choice for inducing apoptosis by NK cells.
Neutrophils cannot
- A. Produce ROS
- B. Produce Defensins
- C. Produce NETs
- D. Present antigens to T cells
Correct Answer: D
Rationale: Neutrophils lack the ability to present antigens to T cells due to their short lifespan and absence of major histocompatibility complex (MHC) class II molecules. This process requires MHC class II presentation, which is typically done by antigen-presenting cells such as dendritic cells, macrophages, and B cells. Neutrophils primarily function in phagocytosis, releasing reactive oxygen species (ROS), defensins, and neutrophil extracellular traps (NETs) to combat pathogens. Thus, the correct answer is D. Other choices are incorrect because neutrophils are capable of producing ROS (A), defensins (B), and NETs (C).