nutrition Flashcards
(39 cards)
B vitamins?
Tigers Raid Nightly. Please Put Back Food Completely!
B1 = thiamine B2 = riboflavin B3 = niacin B5 = pantothenic acid B6 = pyridoxine B7 = biotin B9 = folate B12 = cobalamin
which B vitamins are stored in the liver?
folate (B9)
B12
vit A function?
visual pigment
epithelial cell differentiation –> specialized tissue
prevents squamous metaplasia
** tx: measles, AML-M3
night blindness, dry scaly skin, corneal degeneration, Bitot spots on conjunctiva, immunosuppression?
vit A deficiency
N/V/vertigo, blurred vision?
alopecia, dry skin, hepatic toxicity, pseudotumor?
vit A toxicity
** also a teratogen - cleft palate, cardiac; no isotretinoin for preggos!
thiamine function?
in TPP: pyruvate DH, a-KG dH, transketolase, branched-chain ketoacid DH
polyneuritis, symmetrical mm wasting?
dry beriberi (thiamine deficiency)
high-output cardiac failure, edema?
wet beriberi (thiamine deficiency)
how to dx thiamine deficiency?
administer B1, then measure RBC transketolase activity - if increases, B1 deficient
riboflavin function?
component of FAD and FMN - used in redox reactions
** succ DH in TCA
cheilosis and corneal vascularization?
riboflavin deficiency
niacin synthesis?
derived from tryptophan
needs B2 and B6 for synthesis
niacin function?
component of NAD and NADPH - redox reactions
** tx of dyslipidemia: increases HDL and lowers VLDL
glossitis, diarrhea, dementia, dermatitis?
niacin deficiency!
** causes: Hartnup (decreased trp absorption), malignant carcinoid (increased trp metabolism), INH (decreased B6)
facial flushing, hyperglycemia, hyperuricemia?
niacin excess
** prevent facial flushing with aspirin (caused by prostaglandin)
pantothenic acid function?
component of CoA and FA synthase
dermatitis, enteritis, alopecia, adrenal insufficiency?
pantothenic acid deficiency
pyridoxine function?
converted to PLP - transamination, decarboxylation, glycogen phosphorylase
synthesis of neurotransmitters, heme, niacin, cystathionine, histamine
convulsions, hyperirritability, peripheral neuropathy, sideroblastic anemia?
pyridoxine deficiency
biotin function?
cofactor for carboxylation: pyr carboxylase, AcCoA carboxylase, propCoA carboxylase
dermatitis, alopecia, enteritis caused by ABx or raw egg whites?
biotin deficiency (RARE)
folate function?
converted to THF - 1-carbon transfer and methylation
synthesis of DNA/RNA bases
absorbed in jejunum
small reserve in liver
macrocytic megaloblastic anemia, hypersegmented PMNs, glossitis, increased homocysteine with normal MMA?
folate deficiency
caused by phenytoin, sulfonamides, MTX
cobalamin function?
cofactor for homocystein methyltransferase and methylmalonyl-CoA mutase
synthesized only by microorganisms
LARGE pool in liver