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19 Cards in this Set
- Front
- Back
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eumelanin
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from ellipsoidal melanosomes
dark brown or black. more in mammals |
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pheomelanin
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more sulfur.
from spherical melanosomes yellow/red (found in hairs) |
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How are melanosomes degraded?
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in keratinocytes by lysosomal acid hydrolases.
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MSH
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increases cAMP which increases tyrosinase in the melanosomes.
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Melasma
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estrogen increases MSH
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what two drugs block tyrosinase?
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hydroquinone and azelaic acid
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sacral spot
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benign if widespread. on upper buttocks.
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widespread sacral/mongolian spots are called...
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dermal melanocytosis
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ephelides
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a freckle.
increase # of melanosomes. a localized and exxag response to UV light. |
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lentigo
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liver spots.
increase # of melanocytes in the basal layer. |
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oculocutaneous albinism
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melanocytes present but tyrosinase deficient.
do hair bulb test to dx |
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nevus depigmentosus
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disorder of melanosome aggregation and transfer
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idiopathic guttate hypomelanosis
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drop-like and due to sun exposure.
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vitiligo
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margins are hyperpigmented
tx with psoralens |
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chemical leukoderma
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similar to vitiligo
destruction (chemically) of melanocytes |
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piebaldism
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patchy loss of melanocytes and melanin.
heterochromic irises, deafness, mental retardation. |
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vogt-koyanagi harada
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virus causes it. in adults.
uveitis, vitiligo, alopecia... |
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dihydroxyacetone
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a stain
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psoralens
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used with PUVA.
increases melanocyte numbers, size of melanosomes, tyrosinase activity, and transfer of melanin to keratinocytes. |
