Nokea
A patient with systemic lupus erythematosus (SLE) demonstrates a positive antinuclear antibody (ANA) test and elevated levels of anti-double-stranded DNA (anti-dsDNA) antibodies. Which of the following mechanisms is most likely responsible for the production of these autoantibodies?
- A. Loss of self-tolerance
- B. Failure of innate immunity
- C. Defective T cell activation
- D. Impaired phagocytosis
Correct Answer: A
Rationale: The development of autoantibodies such as antinuclear antibodies (ANA) and anti-double-stranded DNA (anti-dsDNA) antibodies in systemic lupus erythematosus (SLE) is primarily attributed to a loss of self-tolerance. Self-tolerance refers to the immune system's ability to recognize and differentiate self-antigens from foreign antigens. In individuals with SLE, there is a breakdown in immune tolerance mechanisms, leading to the production of autoantibodies against self-antigens like nuclear components (e.g., DNA, RNA, histones). This loss of self-tolerance results in the immune system targeting and attacking its tissues, leading to the systemic inflammation and tissue damage characteristic of SLE. The presence of elevated levels of ANA and anti-dsDNA antibodies in this patient suggests an autoimmune response against nuclear material, further supporting the role of self-tolerance breakdown in SLE
You may also like to solve these questions
Which of the following statements accurately describes the role of dendritic cells in the immune response?
- A. Dendritic cells directly kill infected cells and tumor cells.
- B. Dendritic cells produce antibodies against pathogens.
- C. Dendritic cells activate na(cid:239)ve T cells and initiate adaptive immune responses.
- D. Dendritic cells release histamine and other inflammatory mediators.
Correct Answer: C
Rationale: Dendritic cells play a critical role in initiating adaptive immune responses by capturing antigens from pathogens, migrating to lymphoid organs, and presenting these antigens to naïve T cells. This activation of naïve T cells by dendritic cells is essential for the adaptive immune system to generate specific immune responses against pathogens. Dendritic cells act as professional antigen-presenting cells, which are specialized to capture, process, and present antigens to T cells, thereby facilitating the activation of T cells and the coordination of adaptive immune responses, such as the production of specific antibodies and the generation of memory T cells.
A patient presents with gradual, painless visual field loss in both eyes, particularly in the peripheral vision. Tonometry reveals elevated intraocular pressure (IOP). Which of the following conditions is most likely responsible for this presentation?
- A. Open-angle glaucoma
- B. Closed-angle glaucoma
- C. Age-related macular degeneration
- D. Diabetic retinopathy
Correct Answer: A
Rationale: The patient presents with gradual, painless visual field loss in both eyes, particularly in the peripheral vision, which is characteristic of glaucoma. The elevated intraocular pressure (IOP) on tonometry further supports a diagnosis of glaucoma. Open-angle glaucoma is the most common type of glaucoma and typically presents insidiously with a slow progression of vision loss. In open-angle glaucoma, the drainage angle of the eye remains open but becomes less efficient over time, leading to increased intraocular pressure and optic nerve damage. This results in peripheral visual field loss. Closed-angle glaucoma, on the other hand, presents more acutely with sudden eye pain, redness, and blurred vision due to a sudden increase in intraocular pressure from a blocked drainage angle. Age-related macular degeneration and diabetic retinopathy typically do not present with elevated IOP or peripheral visual field loss.
Following a severe traumatic brain injury, a patient is experiencing alterations in consciousness characterized by periods of wakefulness but with no meaningful interaction with the environment. Which term best describes this state?
- A. Coma
- B. Vegetative state
- C. Minimally conscious state
- D. Locked-in syndrome
Correct Answer: B
Rationale: A vegetative state, now more commonly referred to as unresponsive wakefulness syndrome, describes a condition where the patient is awake but with no awareness of themselves or their surroundings. This state usually follows a severe brain injury, such as traumatic brain injury. Patients in a vegetative state may have sleep-wake cycles, open their eyes, and even exhibit reflex movements, but they do not demonstrate any meaningful interaction with the environment. Differentiating between coma and vegetative state is important, as coma implies a complete lack of consciousness, while patients in a vegetative state have preserved wakefulness without awareness. Minimally conscious state (choice C) refers to a condition where there are some minimal signs of awareness or purposeful interaction, making it a different state than the one described in the scenario. Locked-in syndrome (choice D) is a condition where the patient is conscious and aware but unable to move or communicate due to paralysis, which is not consistent
In conducting a study on sleep, Nurse Trining was asked which of the types of research will be used should it involve collecting numerical data which is most often under considerable control. Her answer should be _________.
- A. Ichnographic
- B. Qualitative
- C. Phenomenological
- D. Quantitative
Correct Answer: D
Rationale: Quantitative research is the type of research that involves collecting numerical data, which can be easily quantified and analyzed statistically. It is characterized by its structured methodology, objectivity, and the ability to control variables to a considerable extent. In the context of a study on sleep, where data related to sleep patterns, duration, quality, etc., need to be measured and analyzed in a systematic manner, quantitative research would be the most appropriate choice. This type of research allows for a more precise understanding of the relationships and patterns within the data, providing valuable insights into the sleep-related factors being studied.
A patient presents with a thyroid nodule and signs of compression such as difficulty swallowing and breathing. Fine-needle aspiration biopsy reveals malignant cells with nuclear features suggestive of papillary thyroid carcinoma. Which endocrine disorder is most likely responsible for these symptoms?
- A. Hashimoto's thyroiditis
- B. Graves' disease
- C. Diabetes mellitus
- D. Papillary thyroid carcinoma
Correct Answer: D
Rationale: Papillary thyroid carcinoma is a type of thyroid cancer that arises from follicular cells of the thyroid gland. It often presents as a thyroid nodule that can cause symptoms of compression due to its enlarging size. The compression symptoms, such as difficulty swallowing and breathing in this case, occur when the thyroid nodule becomes large enough to press on adjacent structures in the neck. Fine-needle aspiration biopsy can confirm the presence of malignant cells with nuclear features typical of papillary thyroid carcinoma, further supporting the diagnosis.