Term
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Definition
| fish, seafood, eggs, meat, vegetable |
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Term
| Effects on Se dietary sources |
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Definition
| varies depending on where source is grown/raised, Se content in meat reflects Se supplement in diets |
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Term
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Definition
| inorganic and organic Se present in body |
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Term
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Definition
| selenite(SeO3 2-), selenate(SeO4 2-), selenide(HSe -) |
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Term
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Definition
| selenocysteine, selenomethionine |
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Term
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Definition
| selenoamino acids absorbed intact as high as 98%, inroganic forms absorbed ~85%, absorption is constant even in deficiency |
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Term
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Definition
| selenomethionine & methionine transported the same, none of the luminal & basolateral inorganic Se transporters have been described |
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Term
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Definition
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Term
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Definition
| concentrations: kidney > liver > RBCs > muscle > spleen > pancreas, muscle has largest Se mass |
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Term
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Definition
| US - 125mcg/L, China - 15mcg/L |
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Term
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Definition
| methylselenol major urinary form, urinary excretion important for homeostasis |
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Term
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Definition
| selenocysteine & selenomethionine catabolism releases inorganic HSe-, SeO3 & SeO4 reduced to HSe-, |
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Term
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Definition
| selenide undergoes enzymatic conversion to selenocysteine, it is then utilized for biosynthesis of selenoproteins |
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Term
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Definition
| functions of most unknown, those that have been characterized participate in antioxidant & anabolic processes |
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Term
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Definition
| GPX1 first discovered selenoprotein, accounts for >50% |
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Term
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Definition
| GPX1 reduces H2O2 utilizing GSH, selenocysteine component necessary for enzyme activity, also may function as a Se buffer |
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Term
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Definition
| plasma GPX, major form of Se in milk |
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Term
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Definition
| structural component of sperm |
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Term
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Definition
| family of 3 selenoenzymes, thyroxine5'-DI1 responsible for conversion of T4 to T3, Se deficiency decreases DI1 activity |
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Term
| Thioredoxin reductases (TRR) |
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Definition
| family of 3 enzymes, TRR1 may regulate intracellular redox state, facilitate transfer of electrons from NADH to thioredoxin, will reduce dehydroascorbate, ascorbate radical, and possibly vit E |
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Term
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Definition
| small selenoprotein found in muscle, implicated in white muscle disease, Prevention: supplementation in soil |
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Term
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Definition
| major plasma selenoprotein & major Se transport protein, accounts for 80% of plasma Se, produced in liver, up to 10 Se/molecule |
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Term
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Definition
| Se has been shown to correct liver necrosis caused by lack methionine, cysteine and vit E |
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Term
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Definition
| 2 main factors in etiology: low Se & viral infection, causes cardiomyopathy, has been nearly eradicated due to Se supplementation |
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Term
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Definition
| endemic dz of cartillage, Se supplementation does not cure, may involve iodine deficiency |
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Term
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Definition
| Se & I deficency contribute to etiology, characterized by enlarged thyroid & decreased intelligence, Se supplementation alone exacerbates dz |
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Term
| Se status assessment (intake) |
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Definition
| plasma/serum Se: reflects recent diet, RBC Se: past 120 days of diet |
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Term
| Se status assessment (functional) |
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Definition
| glutatione peroxidase activity |
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Term
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Definition
| Men&women: 55 mcg/d, Pregnancy: 59mcg/d, Lactation: 70 mcg/d, UL: 400 mcg/d |
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Term
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Definition
| inorganic and amino acid Se highly bioavailable and toxic in excess |
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Term
| Selenosis (chronic Se toxicity) |
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Definition
| commonly associated w/ changes in nail structure, loss of nails&hair, Continued ingestion leads to lesions of skin & nervous system, nausea, diarrhea, weakness, symptoms present w/ 3.2-6.7 mg/d |
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Term
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Definition
| caused by ingestion of gram quantities, GI and neurological disturbances, MI, renal failure, acute respiratory distress syndrome, No antidote for overdose |
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Term
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Definition
| no effect on squamous cell carcinoma, but decreased lung, prostate, and colon cancer incidents |
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Term
| Se & Vit E in prostate cancer |
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Definition
| Se/Vit E or both did not significantly decrease incident of prostate cancer in SELECT |
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