Biochem: Nutrition

Question 1

Sx of vit A def?

Answer 1

night blindness, dry skin, xeropthalmia, keratomalacia, bitot spots, squamous metaplasia

Question 2

Sx of vit A tox?

Answer 2

arthralgias, fatigue, headaches, skin changes, sore throat, alopecia, teratogen, increased ICP

Question 3

In general, what can B complex deficiencies cause?

Answer 3

dermatitis, glossitis and diarrhea

Question 4

What can vitamin A be used to treat?

Answer 4

AML, measles

Question 5

What is thiamine found in? What does it assist in?

Answer 5

thiamine pyrophosphate (TPP), a cofactor for decarboxylation reactions

• pyruvate dehydrogenase
• a Ketoglutarate dehydrogenase
• transketolase
• branched chain amino acid dehydrogenase

Question 6

What happens with B1 def?

Answer 6

ATP depletion, woresened by glucose infusion

Wernicke Korsakoff and beriberi

Question 7

What is the triad of wernicke korsakoff?

Answer 7

confusion, opthalmoplegia, atasia (+confabulation, personality change, memory loss)

Question 8

What sx of wernicke korsakoff is often permanent?

Answer 8

memory loss

Question 9

What is B2 a cofactor for?

Answer 9

riboflavin
oxidation and reduction rxs (dehydrogenases)
is in FAD and FMN

Question 10

What is seen in B2 deficiency?

Answer 10

cheilosis, corneal vascularization glossitis

Question 11

What does B3 contribute to?

Answer 11

alt name-niacin

NAD+ & NADP+, for redox rxns

Question 12

How is B3 made?

Answer 12

from tryptophan

requires B6 and B2

Question 13

What is seen in B3 def?

Answer 13

glossitis, pellagra (can be caused by hartnup disease), malignant carcinoid syndrome, INH

Question 14

What are the sx of pellagra?

Answer 14

Diarrhea, dementia and dermatitis

Question 15

What is seen with excess niacin (B3)?

Answer 15

facial flushing

Question 16

What is B5 used for?

Answer 16

alt name-pantothenate

component of CoA and fatty acid synthase

Question 17

What is seen in B5 def?

Answer 17

dermatitis, enteritis, alopecia, adrenal insufficiency

Question 18

What is B6 used for?

Answer 18

converted to pyridoxal phosphate-cofactor in transamination/deamination, decarboxylation rxns, glycogen phosphorylase
for synthesis of cystathionin, heme, niacin, histamine and NTs (5-HT, Epi, NA, GABA)

Question 19

What is seen in B6 deficiency??

Answer 19

convulsions, hyperirritability, peripheralneuropathy

sideroblastic anemias

Question 20

What vitamins does isoniazid inhibit?

Answer 20

B6 and B3

pyridoxine and niacin

Question 21

What is biotin used for?

Answer 21

cofactor for carboxylation enzymes

• pyruvate carboxylase
• Acetyle CoA carboxylase
• propionyl CoA carboxylase

Question 22

What can cause B7 deficiency?

Answer 22

avidin in raw egg whites or abx use

Question 23

Sx of B7 deficiency?

Answer 23

dermatitis, alopecia, enteritis

Question 24

What is B9 used for?

Answer 24

converted to tetrahydrofolate-a coenzyme for 1-carbon transfer/methylation rxns
for synthesis of nitrogenous bases in DNA and RNA

Question 25

What is seen in B9 deficiency?

Answer 25

macrocytis megaloblastic anemia w/hypersegmented PMNs NO neurological sx NT defects

Question 26

what drugs can cause B9 deficiency?

Answer 26

phenytoin, sulfonamides, MTX

Question 27

What is B12 used for?

Answer 27

cofactor for hmocysteine methyltransferase and methylmalonyl coA mutase

Question 28

What is seen in B12 def?

Answer 28

macrocytic megaloblastic anemia, hypersegmented PMNs, neurologic sx (parasthesias, subacute combined degeneration)

Question 29

What lab values are seen in B12 def?

Answer 29

increased MMA | increased homocystiene

Question 30

What causes B12 def?

Answer 30

malabsorption, lack of intrinsick factor, crohns, diphyllobothrium latum

Question 31

What is SAM made of?

Answer 31

ATP and methionine

Question 32

What does SAM do?

Answer 32

donate methy units

Question 33

What doese regeneratin of methionine/SAM depend on?

Answer 33

B12 and folate

Question 34

What is SAM required for?

Answer 34

conversion of NE to Epi

Question 35

What does vit C do?

Answer 35

antioxidant facilatates Fe abs by keeping 2+ for hydroxylation of lysine & proline in collage synth needed to convert dopamine to NE (dopamine B hydroxylase)

Question 36

What is seen in Vit C def?

Answer 36

SCURVY swollen gums, bruisnig hemarthrosis, anemia, poor wound healing weakened immune response

Question 37

What is seen in Vit C tox?

Answer 37

N/V, diarrhea, fatigue, sleep issue | increased risk iron toxicity in predisposed

Question 38

What is the form of vit D stored?

Answer 38

25-OH D3

Question 39

What is an alternative name for active vit D?

Answer 39

calcitriol

Question 40

What is Vit D used for?

Answer 40

increasing intestinal absoprtion of calcium and phospase, increasing bone mineralization

Question 41

Vit D deficiency?

Answer 41

Rickets-kids, bone pain and deformity Osteomalacia-adults, bone pain, muscle weakness hypocalemic tetany, breast milk has decreased vit D (esp in dark skinned pts)

Question 42

What is seen in vit D tox?

Answer 42

hypercalcemia, hypercalciuria, loss of appetite, stupor | seen w/ sarcoidosis (increased activation of vit D by epitheliod MOs)

Question 43

What is another name for vit E?

Answer 43

a tocopherol

Question 44

What is vit Es job?

Answer 44

antioxidant-protects RBCs and membranes from free radical damage

Question 45

What is seen in Vit E deficiency?

Answer 45

fragility of erythrocytes/hemolytic anemia, muscle (esp proximal) muscle weakness, posterior column and spinocerebellar tract demyelination

Question 46

What is Vit K for?

Answer 46

catalyzes gammacarboxlation of gluatmic acid in blood clotting proteins, made by intestinal flora

Question 47

What is seen w vit K def?

Answer 47

neonatal hemorrhage w/prolonged PT and PTT but normal bleeding time can occur after broad spectrum abx

Question 48

What factors need vit K?

Answer 48

2, 7, 9, 10, protein C, protein S

Question 49

What is zinc needed for?

Answer 49

over 100 enzymes, essential for lactate dehydrogenase and carbonic anhydrase, needed for zinc fingers

Question 50

Zinc def sx?

Answer 50

delayed wound healing, hypogonadism, decreased adult hair, dysgeusia, anosmia, may predispose to alcoholic cirrhosis, impaired night vision, anorexia, diarrhea, growth retardation, decreased mental function, infertility

Question 51

What drug inhibits alcohol dehydrogenase?

Answer 51

fomepizole | antidote for methanol or ethylene glycol poisoning

Question 52

What drug inhibits acetaldehyde dehydrogenase?

Answer 52

disulfiram | enhances hangover sx

Question 53

What is the limiting reagent in alcohol metabolism?

Answer 53

NAD+

Question 54

what type of kinetics for EtOH met?

Answer 54

zero order

Question 55

Describe ethanol hypoglycemia

Answer 55

increased NADH:NAD+ ratio in the liver, diverts pyruvate to lactate & OAA to malate, inhibits gluconeogenesis and stimulates fatty acid synthesis leads to hypoglycemia and hepatic fatty change over production of lactate can lead to acidosis, depletion of OAA shuts down TCA, leads to ketone production

Question 56

What drugs have a disulfiram like reaction?

Answer 56

metronidazole certain cephalosporins procarbazine 1st gen sulfonylureas

Question 57

Sx of kwashiorkor

Answer 57

skin lesions, liver malfunction (fatty), small child w/swollen belly, edema, anemia protein lacking

Question 58

Sx of marasmus

Answer 58

tissue and muscle wasting, loss of subcut fat, variable edema

Question 59

What causes refeeding s/o?

Answer 59

overall ATP depletion | decreased serum Mg2+, PO4-, K+---arrhythmias and neurologic problems