Set 19 Flashcards
What disorders can cause cotton-wool spots on the retina?
Cotton wool spots are pale areas of various sizes that look like cotton - infarcts of the nerve fiber layer of the retina
Main causes: Chronic HTN and diabetic retinopathy
Also: AIDS, Lupus, some Vasculitis (temporal arteritis, Wegener granulomatosis, Polyarteritis nodosum)
Which cardiac valve is most commonly involved in infective endocarditis and acute rheumatic fever?
Mitral valve (vs. Tricuspid valve in IV drug users)
Name the syndromes below that are common causes of anovulation.
Cushing syndrome
Amenorrhea + hirsutism + obesity
Cushing syndrome: Cushing syndrome
Amenorrhea + hirsutism + obesity: PCOS
What neurotransmitters in the brain are affected in each of the following disorders? Are the levels increased or decreased?
Schizophrenia
Increased dopamine
What neurotransmitters in the brain are affected in each of the following disorders? Are the levels increased or decreased?
Parkinson disease
Decreased dopamine, increased 5-HT, increased ACh
What neurotransmitters in the brain are affected in each of the following disorders? Are the levels increased or decreased?
Alzheimer disease
Decreased ACh
What neurotransmitters in the brain are affected in each of the following disorders? Are the levels increased or decreased?
Huntington disease
Decreased GABA, decreased ACh and increased dopamine
What neurotransmitters in the brain are affected in each of the following disorders? Are the levels increased or decreased?
Anxiety
Increased NE, decreased GABA, decreased 5-HT
What neurotransmitters in the brain are affected in each of the following disorders? Are the levels increased or decreased?
Depression
Decreased NE, DA, and 5-HT
What is the underlying cause of DiGeorge syndrome? What are the manifestations of DiGeorge syndrome?
22q11 deletion - aberrent development of the 3rd and 4th pharyngeal pouches (absent thymus and parathyroids)
CATCH: Cleft palate, Abnormal facies, Thymic aplasia —> T cell deficiency (recurrent viral and fungal infections), Cardiac defects, Hypocalcemia secondary to parathyroid aplasia (tetany)
A type 2 diabetic with a HgbA1c of 10% presents to your clinic with many complaints. You are concerned about the effect of the patient’s long-term hyperglycemia. What diabetic complications can be attributed to sorbitol-induced osmotic damage? What enzyme converts glucose to sorbitol?
Sorbitol is the alcohol counterpart of glucose and is converted via aldose reductase. It is an alternative method of trapping glucose in the cell. Some tissues (liver, ovaries and seminal vesicles) also have sorbitol dehydrogenase that can further convert sorbitol to fructose. Tissues without a sufficient amount of this enzyme (schwann cells, retina, kidney, lens) are at risk for intracellular sorbitol accumulation causing osmotic damage (cataracts, retinopathy, and peripheral neuropathy seen with chronic hyperglycemic in diabetes).
What efferent fibers carry input from the brain that influences the outer hair cells (OHCs) of the cochlea in much the same way that gamma motor neurons influence muscle spindles? What is the result of this input? What is the result of damaging the OHCs (as with antibiotics such as gentamicin and streptomycin)?
Olivocochlear bundles (superior olive to cochlea) Result is contraction of outer hair cells and stiffening of basilar membrane in cochlea which will sensitize inner hair cells to a particular frequency (can listen for and discriminate sounds when there is other background noise) Damage gives wide deflection of basilar membrane —> causes hearing loss
What is type II (β) error?
Stating that there is not an effect or difference when one exists (null hypothesis is not rejected when it is in fact false). Also known as a false negative (B = blind to a difference). B is the probability of making a type II error.
A child in India is brought to the doctor with symptoms of muscle weakness, malaise, headache, fever, and hyporeflexia. For the past few weeks he had been swimming in a waterway known to contain sewage. You think this boy has contracted a pathogen via the fecal-oral route. What area of the body is this pathogen attacking to give the neurologic symptoms seen?
Destruction of cells in anterior horn of spinal cord (LMN death) - polio virus
What are the risk factors for osteosarcoma?
Paget disease of the bone Bone infarcts Radiation Familial retinoblastoma Li-Fraumeni syndrome (germline p53 mutation) Male sex, 10-20 years
