Neurology Amboss Flashcards

Question

Warfarin in pregnancy

Answer 1

warfarin is known to cross the placenta, and its teratogenic effects are well documented, as seen in this neonate: nasal and midface hypoplasia; shortened limbs and digits; calcifications of the vertebral, humeral, and femoral epiphyses (stippled epiphysis); and, as shown by the MRI image, Dandy-Walker syndrome (superior displacement and hypoplasia of the superior vermis). Unfractioned heparin/low molecular weight heparin is better suited... but is not good for reducing thomboembolic events if there is a mechanical heart valve

Answer 2

Epidermis, adenohypohysis (from rathke pouch), lens of eye, epithelial lining of oral cavity, sensory organs of ear, olfactor epithelium, below pectinate line in anal canal, parotid, sweat, mammary gland

Answer 3

Obese, intellectual disability hypogonadism

Answer 4

ataxia, seizures, inappropriate laughter

Answer 5

day 24 and the posterior neuropore occurs at 28 days

Answer 6

Mechanically gated potassium (K+) channels on the tips of stereocilia open when stretched, causing K+ influx and depolarization, triggering voltage-gated calcium (Ca2+) channels to open. This Ca2+ influx into the hair cell causes release of excitatory neurotransmitters from synaptic vesicles, which diffuse through the perilymph to spiral ganglia neurites.

Answer 7

Age-related degeneration of the organ of Corti (or presbycusis) is a type of sensorineural hearing loss that is part of the normal aging process. It is the most common cause of sensorineural hearing loss in the elderly and manifests with gradually worsening high-frequency hearing loss. The cause of presbycusis is degeneration of the proximal hair cells of the organ of Corti (depicted in the drawing), which lie in the proximal portion of the basilar membrane (farthest from the helicotrema or apex and closest to the ossicles and oval window). This is the thinnest and least compliant portion of the basilar membrane and is responsible for sensing high-frequency sounds.

Answer 8

decreased production of collagen type 1 bone (skin tendon, dentin, fascia, cornea) Brittle bone disease, COL1A1, COL1A2, AD, multiple fractures bone deformities, blue sclerae, translucent connective tissue over chordial veins, tooth abnormalities, conductive hearing loss (OSSICLE damage) Glycosylation—glycosylation of pro-α-chain hydroxylysine residues and formation of procollagen via hydrogen and disulfide bonds (triple helix of 3 collagen α chains). LENS 4 letters type 4 collagen type 1 CORNY Type 2 HUMOURS (vitrious)

Answer 9

Cross-linking—reinforcement of many staggered tropocollagen molecules by covalent lysine-hydroxylysine cross-linkage (by copper-containing lysyl oxidase) to make collagen fibrils. Problems with cross-linking 􏰂Menkes disease. X-linked recessive connective tissue disease caused by impaired copper absorption and transport due to defective Menkes protein (ATP7A, vs ATP7B in Wilson disease). Low copper levels (vs high levels in Wilson disease). Leads to􏰄activity of lysyl oxidase (copper is a necessary cofactor)􏰂 defective collagen. Results in brittle, “kinky” hair, growth retardation, hypotonia,􏰃risk of cerebral aneurysms. MENKE IS IN THE HEAD hypotonia.... dead vibes... cerebral aneurysms, HAIR fucked, growth fucked like a dumbo

Answer 10

Arachnodactyly

Answer 11

would result in sensorineural hearing loss and potentially equilibrium disturbances. However, patients with cranial nerve VIII lesions have hearing loss in the high-frequency range and exhibit problems with speech discrimination.

Answer 12

result in sensorineural hearing loss, but would not result in vertigo. Presbycusis, age-related sensorineural hearing loss from hair cell degeneration, is usually symmetric and tends to affect high-frequency sound perception.

Answer 13

idiopathic disorder that usually affects people between the ages of 30 and 60 and involves episodes of vertigo that typically last for hours. Nystagmus is present during the vertiginous attacks, but would not be seen on exam of this patient who is not acutely symptomatic at presentation. Patients also have fluctuating difficulty hearing that often progresses to permanent, low-frequency sensorineural hearing loss in both ears. Aural fullness and tinnitus are also associated.

Answer 14

Rathke pouch, most common non glial brain tumor in children, mimodal age distribution, arise from epithelial nest

Answer 15

histidyl tRNA synthetase and most commonly found in patients with idiopathic inflammatory myopathies, specifically polymyositis. Weakness in proximal muscles GBS remember is antibodies is myelin and is ascending paralysis

Answer 16

antibodies against calcium channels in presynaptic nerve terminal. Proximal muscle weakness, decreased deep tendon reflexes, post tetanic potentiation (that is why it improves with movement)

Answer 17

Small diameter motor neurons that innervate the intrafusal muscle fiber within a muscle spindle. The motor neurons maintain intrafusal fiber tension during extrafusal muscle fiber contraction

Answer 18

constitute bulk of the contracting muscle belly. They produce the muscle tension

Answer 19

they initiate inverse stretch reflex, in which muscle contraction is inhibited during excessive stretch. These receptors are found in the tendon near the muscle tendon junction. When a weight lifter drops weight the muscle contraction is inhibited by this reflex.

Answer 20

Yes, and overuse of diuretics causes metabolic alkalosis