Patients after transplantation of allogeneic stem cells are monitored periodically for reactivation of

Correct Answer: B

Rationale: The correct answer is B: CMV. Patients after allogeneic stem cell transplantation are monitored for CMV reactivation due to its potential to cause severe complications in immunocompromised individuals. CMV can lead to organ damage and even mortality in these patients. Monitoring for CMV reactivation allows for early detection and prompt intervention. Incorrect Choices: A: HAV - Hepatitis A virus reactivation is not commonly monitored in post-transplant patients. C: Rubella virus - Rubella is not a common concern for reactivation in this patient population. D: Measles virus - Measles reactivation is not typically monitored in these patients.

Correct Answer: B

Rationale: The correct answer is B: CMV. Patients after allogeneic stem cell transplantation are monitored for CMV reactivation due to its potential to cause severe complications in immunocompromised individuals. CMV can lead to organ damage and even mortality in these patients. Monitoring for CMV reactivation allows for early detection and prompt intervention. Incorrect Choices: A: HAV - Hepatitis A virus reactivation is not commonly monitored in post-transplant patients. C: Rubella virus - Rubella is not a common concern for reactivation in this patient population. D: Measles virus - Measles reactivation is not typically monitored in these patients.

Correct Answer: D

Rationale: The correct answer is D: Relenza and Tamiflu. Both Relenza and Tamiflu are anti-influenza drugs that target the neuraminidase enzyme of the influenza virus, thereby inhibiting its replication and spread. Maxi Grip (A) is not an anti-influenza drug, Theraflu (B) contains different active ingredients, and Amantadine and Rimantadine (C) target a different viral protein, M2 ion channel. Therefore, choices A, B, and C are incorrect as they do not specifically target neuraminidase for influenza treatment.

Correct Answer: A

Rationale: The correct answer is A: Streptococcus pneumoniae. This bacterium is a Gram-positive cocci that often appear in pairs and can have a capsule. It is a common cause of sore throat and fever, known as streptococcal pharyngitis. Staphylococcus aureus (B) is a Gram-positive cocci but does not typically form pairs. Neisseria meningitidis (C) is a Gram-negative diplococcus and is more associated with meningitis. Klebsiella pneumoniae (D) is a Gram-negative rod and not typically associated with sore throat and fever.

Correct Answer: C

Rationale: Chitin is a polysaccharide found in the cell walls of fungi. Bacteria have cell walls made of peptidoglycan, not chitin. Viruses do not have cell walls as they are acellular entities. Therefore, the correct answer is A: fungi.

Correct Answer: A

Rationale: The correct answer is A: Mycobacterium tuberculosis. This bacterium is known for causing tuberculosis, as it specifically infects the lungs and can lead to serious respiratory issues. Mycobacterium leprae (Choice B) causes leprosy, not tuberculosis. Escherichia coli (Choice C) is a common bacteria found in the intestines and is not associated with tuberculosis. Streptococcus pneumoniae (Choice D) causes pneumonia, but not tuberculosis. Therefore, the correct choice is A because Mycobacterium tuberculosis is the specific bacterium responsible for causing tuberculosis.

Correct Answer: C

Rationale: The correct answer is C: Endospore. Endospores are dormant, tough, and non-reproductive structures formed by certain bacteria as a response to unfavorable conditions. They help bacteria survive harsh environments such as extreme temperatures, desiccation, and exposure to harmful chemicals. The other choices, Flagella (A), Capsule (B), and Pili (D), do not directly contribute to bacterial survival in adverse conditions. Flagella aid in bacterial movement, capsules provide protection from immune system attacks, and pili are involved in attachment to surfaces or other cells. Endospores are specifically designed for survival during unfavorable conditions, making them the correct choice in this scenario.

Correct Answer: B

Rationale: The correct answer is B because endotoxins are part of the outer membrane of gram-negative bacteria. When these bacteria undergo cell lysis, the endotoxins are released, causing harmful effects. This process does not occur during bacterial replication (choice A), antibody production (choice C), or formation of spores (choice D). Bacterial replication involves the creation of new bacterial cells, not the release of endotoxins. Antibody production is the immune response to pathogens, not the direct cause of endotoxin release. Spores are dormant structures formed by some bacteria, which are not directly related to the release of endotoxins.

Correct Answer: A

Rationale: The correct answer is A: Aspergillosis and candidiasis. Galactomannan is a polysaccharide found in Aspergillus cell walls and is detected in patients with invasive aspergillosis. Free mannan is a polysaccharide found in Candida cell walls and is detected in patients with candidiasis. Therefore, detection of galactomannan and free mannan is specific for diagnosing Aspergillosis and candidiasis. Choices B, C, and D are incorrect as HIV infection, syphilis, and leptospirosis do not involve the detection of galactomannan or free mannan for diagnosis.