Exam Flashcards

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Answer: bcl-2 activation

Bcl-2 is an anti-apoptotic protein whose activation or overexpression inhibits programmed cell death. This prolonged cell survival is a hallmark of many cancers, particularly follicular lymphoma, where a t(14;18) translocation leads to BCL2 overexpression. Therefore, bcl-2 activation contributes to oncogenesis by preventing the natural elimination of abnormal cells.

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Answer: Complement (C6-C8) components

Deficiencies in the terminal complement components (C5-C9), particularly C6, C7, or C8, impair the formation of the membrane attack complex (MAC). The MAC is crucial for lysing Gram-negative bacteria, especially Neisseria species. Therefore, individuals with these deficiencies are at increased risk for recurrent Neisseria infections, such as meningococcal meningitis or gonococcal infections.

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Answer: Rathke’s pouch

Rathke's pouch is an ectodermal invagination from the roof of the primitive oral cavity that gives rise to the anterior pituitary gland (adenohypophysis). Craniopharyngiomas are tumors that arise from remnants of Rathke's pouch. These tumors are typically suprasellar and can cause symptoms due to compression of surrounding structures like the optic chiasm or hypothalamus, often leading to endocrine dysfunction.

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Answer: 12 hours

Without specific context, 12 hours is a common interval in medicine. It often represents the dosing frequency for medications taken twice daily (BID) to maintain therapeutic levels. It can also be relevant for monitoring certain physiological parameters or for the half-life of specific substances in the body.

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Answer: Hepatitis B virus (HBV)

Hepatitis B virus (HBV) is a well-established risk factor for hepatocellular carcinoma (HCC). Chronic HBV infection leads to persistent inflammation, hepatocyte damage, and regeneration, which increases the risk of genetic mutations and malignant transformation. The viral DNA can also integrate into the host genome, further contributing to oncogenesis.

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Answer: Delirium

Delirium is an acute, fluctuating disturbance in attention and cognition, often accompanied by altered consciousness. It is typically caused by an underlying medical condition, substance intoxication, or withdrawal. Key features include its sudden onset, fluctuating course, and often reversible nature once the underlying cause is addressed.

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Answer: Pheochromocytoma

Pheochromocytoma is a tumor of the adrenal medulla that secretes excessive amounts of catecholamines (epinephrine and norepinephrine). This leads to classic symptoms such as episodic hypertension, palpitations, headaches, and sweating. It is important to diagnose and treat pheochromocytoma due to the risk of hypertensive crises and cardiovascular complications.

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Answer: Caudate nucleus

Huntington's disease is a neurodegenerative disorder characterized by progressive motor, cognitive, and psychiatric symptoms. Pathologically, it is associated with selective atrophy of the caudate nucleus and putamen (components of the striatum). This neuronal loss, particularly in the caudate, leads to the characteristic choreiform movements seen in the disease.

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Answer: Type II pneumocytes

Type II pneumocytes are cuboidal cells found in the alveolar walls. Their primary functions include producing and secreting surfactant, which reduces surface tension in the alveoli and prevents their collapse. They also serve as progenitor cells, capable of proliferating and differentiating into Type I pneumocytes to repair damaged alveolar lining.

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Answer: Alzheimer disease

Alzheimer disease is the most common cause of dementia, characterized by progressive memory loss and cognitive decline. Pathologically, it involves the accumulation of amyloid plaques and neurofibrillary tangles (tau protein) in the brain, leading to neuronal dysfunction and death. It typically presents with insidious onset and gradual progression of symptoms.

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Answer: Drug-induced lupus

Drug-induced lupus erythematosus (DILE) is a lupus-like syndrome caused by certain medications, such as procainamide, hydralazine, and isoniazid. It typically presents with arthralgias, myalgias, and serositis, but rarely involves renal or CNS manifestations. A key laboratory finding is the presence of anti-histone antibodies, and symptoms usually resolve upon discontinuation of the offending drug.

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Answer: Aortic dissection

Aortic dissection is a life-threatening condition where a tear in the intima allows blood to enter the media, creating a false lumen. It typically presents with sudden onset of severe, 'tearing' or 'ripping' chest or back pain that may radiate. Risk factors include hypertension and connective tissue disorders like Marfan syndrome.

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Answer: Vagus

The vagus nerve (Cranial Nerve X) is a mixed nerve with extensive parasympathetic innervation to the thoracic and abdominal viscera. It plays a crucial role in regulating heart rate, digestion, and respiratory function. Its motor component innervates muscles of the pharynx and larynx, important for swallowing and speech.

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Answer: Sarcoidosis

Sarcoidosis is a multisystem granulomatous disease of unknown etiology, characterized by the formation of non-caseating granulomas in various organs. It most commonly affects the lungs and lymph nodes, but can also involve the skin, eyes, liver, and heart. Clinical presentation varies widely depending on the organs involved.

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Answer: Dorsal column

The dorsal columns (fasciculus gracilis and fasciculus cuneatus) are ascending sensory tracts in the spinal cord. They are responsible for transmitting fine touch, vibration, and proprioception from the ipsilateral side of the body. Damage to the dorsal columns, as seen in conditions like tabes dorsalis or vitamin B12 deficiency, leads to impaired sensation in these modalities.

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Answer: "Doctor, you must be wrong."

This question likely refers to Kübler-Ross's stages of grief. 'Doctor, you must be wrong' represents the stage of denial, which is typically the first reaction to receiving a devastating diagnosis. In this stage, individuals struggle to accept the reality of their situation.

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Answer: Colchicine

Colchicine is an anti-inflammatory agent primarily used for the acute treatment and prophylaxis of gout. It works by inhibiting microtubule polymerization, thereby disrupting neutrophil migration and activity in inflamed joints. This reduces the inflammatory response to uric acid crystals.

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Answer: vitamin A deficiency

Vitamin A deficiency is a common cause of night blindness (nyctalopia) and xerophthalmia (dry eyes). Vitamin A is crucial for the formation of rhodopsin, a photopigment in the rod cells of the retina, which is essential for vision in low light conditions. Severe deficiency can lead to permanent blindness.

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Answer: Vibratory sense from the ipsilateral arm

This question likely refers to the sensory deficits associated with a specific lesion, possibly a spinal cord lesion affecting the dorsal columns. The dorsal columns carry vibratory sense and proprioception from the ipsilateral side of the body. Therefore, a lesion affecting the dorsal column at a cervical level would impair vibratory sense from the ipsilateral arm.

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Answer: Left atrium

The left atrium receives oxygenated blood from the pulmonary veins and pumps it into the left ventricle. In mitral stenosis, the mitral valve opening is narrowed, impeding blood flow from the left atrium to the left ventricle. This leads to increased pressure and dilation of the left atrium, which can cause symptoms like dyspnea and predispose to atrial fibrillation.