Term
| Two very good sources of zine |
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Definition
| red meats (especially organs) and seafood (especially oysters and mollusks) |
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Term
| two good plant sources of zinc |
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Definition
| whole grains (espeically bran and germ) and vegetables (especially leafy green) |
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Term
| Metalloenzymes as endogenous sources of zinc |
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Definition
| yes, carboxypeptidase is a metalloenzyme, and after its activity it's hydrolyzed and zinc is released |
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Term
| zinc absorption transport present on bursh border membrane |
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Definition
| Zrt and Irt-like protein (ZIP)4 is thought to be primary transporter |
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Term
| phytates, oxalates, and polyphenols effect on zinc absorption |
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Definition
phytates-found in plant food, bind zinc using O2, this zinc-phytate complex is large and poorly absorbed
oxalate-binds zinc and inhibits absorption
polyphenols-binds zinc and inhibits absorption |
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Term
| effect of nonheme iron on zinc absorption |
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Definition
| most commonly inhibited when amount of nonheme iron exceeds that of zinc; ingestion of nonheme iron w/ zinc from food does not have same effect |
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Term
| two proteins zinc binds to in enterocyte which AA in these proteins bind to zinc |
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Definition
| cysteien-rich intestinal protein (CRIP); metallothionein(when bound to zinc); cystein fxns in metal binding |
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Term
| transporter that transports zinc out of enterocyte into portal vein |
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Definition
| mainly bound loosley to albumin |
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Term
| protein responsible for transporting 60% of zinc in blood |
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Definition
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Term
| during infection zinc is preferentially taken up by liver and stored, how does this effect MO growth |
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Definition
| creates decreased in blood [zinc] (hypozincemia) and prevents MO in blood from using zinc for its own multiplication and growth |
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Term
| which two proteins provide zinc when intake is insufficient |
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Definition
| zinc-containing enzymes and metallothionein |
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Term
| metallothionein [] of which two cells decrease due to reduced dietary intake |
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Definition
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Term
| how zinc influences gene expression of thionein |
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Definition
| increased zinc causes increased thionein synthesis; metal regulatory elements (MREs) made of specific nucleotide sequences are found in the promoter region of the thionein gene, zinc may interact w/ MREs alone or thru metal transcription facter to induce thionein synthesis |
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Term
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Definition
| a decrease in thyroid hormones and BMR has been observed in subjects receiving a zinc restricted diet |
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Term
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Definition
| zinc is a compound of gustin, a protein involved in taste activity |
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Term
| zinc effect on membrane and cytoskeleton |
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Definition
| thought itself to stabilize phospholipids and thiol groups, prevent oxidation, and may stabilize membranes by promoting associations b/w membrane skeletal and cytoskeletal protiens; found bound to tubulin |
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Term
| zinc and membrane stability and enzymes |
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Definition
| may affect activity of alkaine phosphatase carbonic anhydrase and superoxide dismutase, which control sturctures and fxns of membranes |
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Term
| 3 primary routes of zinc excretion |
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Definition
1) GI tract (most lost in feces)
2) kidneys
3) skin (integument and sweat) |
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Term
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Definition
| men: 11 mg/day women: 8 mg/day pregnant and lactating need more |
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Term
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Definition
-growth retardation (cell division inadequate)
-skeletal abnormalities from imapaired dev. of epiphyseal cartilage
-defective collagen synthesis or cross-linking
-poor wound healin
-dermatits (espeically around orifices)
-delayed sexual maturation in children
-hyogeusia (blunting a sense of taste)
-alopecia
-impaired immune fxn
-impaired protein synthesis |
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Term
| what is commonly used method to assess zinc status |
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Definition
| serum zinc, with fasting [] <70 micro g/dL suggesting deficiency; interpretation must be made with caution, b/e [] are influenced by many factors unrelated to zinc depletion |
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