Term
What are the 3 major porphyrins? |
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Definition
uroporphyrin, coproporphyrin, protoporphyrin |
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Term
Where does heme synthesis occur? |
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Definition
in all cells; greatest in bone marrow and liver |
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Term
What is the rate limiting step in heme synthesis? |
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Definition
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Term
How is ALA synthetase regulated? |
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Definition
by heme- excess heme inhibits; deficit of heme stimulates |
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Term
A group of disorders that demonstrate a defect in the heme biosynthetic pathway, resulting in abnormal porphyrin metabolism and overproduction of heme precursors. |
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Definition
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Term
What are the 2 ways to classify porphyrias? |
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Definition
erythropoietic or hepatic; neurological or cutaneous |
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Term
Which type of porphyria is characterized by acute attacks of abdominal pain, constipation, neuromuscular signs, and psychotic behavior? |
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Definition
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Term
Which type of porphyria is characterized by photosensitivity and skin lesions without neurological signs or symptoms? |
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Definition
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Term
What are the 3 neurological porphyrias? |
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Definition
acute intermittent porphyria; variegate porphyria; coproporphyria |
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Term
What are the 3 cutaneous porphyrias? |
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Definition
congenital erythropoietic porphyria; protoporphyria; porphyria cutanea tarda |
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Term
What is the most common neurological porphyria? |
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Definition
acute intermittent porphyria |
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Term
What 2 compounds are seen in urine during acute attacks of neurological porphyrias? |
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Definition
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Term
Which neurological porphyria is distinguished from the others by increased excretion of protoporphyrin and coproporphyrin in feces? |
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Definition
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Term
What compounds are increased in cutaneous porphyrias? |
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Definition
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Term
What is the rarest and most severe cutaneous porphyria? |
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Definition
congenital erythropoietic porphyria |
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Term
Which porphyria is associated with erythrodontia? |
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Definition
congenital erythropoietic porphyria |
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Term
Which cutaneous porphyria is associated with increased PROTO and FEP in blood? |
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Definition
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Term
Which cutaneous porphyria usually is dormant until liver disfunction develops? |
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Definition
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Term
Watson-Schwartz is the name of a colorimetric method used to measure what? |
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Definition
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Term
Which is more specific for porphyria- ALA or PBG? |
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Definition
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Term
In lead poisoning, what happens to ALA? PBG? FEP? |
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Definition
increased ALA, normal PBG, increased FEP |
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Term
What sample should be used for blood lead and why? |
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Definition
whole blood because over 90% of lead is in erythrocytes |
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Term
Isolated elevated COPRO without other porphyrins elevated is associated with what disorder? |
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Definition
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Term
In iron deficiency, what happens to FEP? |
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Definition
increased- zinc replaces iron to form zinc protoporphyrin (FEP) |
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Term
What state does iron have to be in in order to be absorbed? |
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Definition
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Term
What is the transport protein for iron? |
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Definition
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Term
What is the major storage form of iron? |
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Definition
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Term
Where is most of the ferritin stored? |
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Definition
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Term
What kind of test is used to measure serum iron? |
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Definition
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Term
What kind of test is used to measure ferritin? |
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Definition
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Term
What is the single most reliable indicator of iron deficiency? |
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Definition
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Term
What is the effect of iron deficiency on TIBC? |
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Definition
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