vitamins

Question 1

functions of vitamin A

Answer 1

antioxidant
specialized epithelium
vision

Question 2

vit A used in the treatment of (2)

Answer 2

measles

AML M3

Question 3

symptoms of vit A deficiency

Answer 3

first- night blindness

also corneal ulcerations, dry skin

Question 4

symptoms of vit A excess (4)

Answer 4

increased ICP/pseudotumor
bone/joint pain
hair loss
hepatitis

Question 5

teratogenic effects of excess vitamin A

Answer 5

cleft palate, cardiac abnormalities

Question 6

vitamin B1

Answer 6

thiamine

Question 7

TPP is a cofactor for (4)

Answer 7

pyruvate dehydrogenase complex
a-ketoglutarate dehydrogenase complex
transketolase
branched-chain amino acid dehydrogenase

Question 8

thiamine deficiency

Answer 8

impaired glucose metabolism, results in beriberi and WK

Question 9

dry beriberi

Answer 9

peripheral neuropathy, muscle wasting

Question 10

wet beriberi

Answer 10

high output heart failure

edema

Question 11

areas of brain damaged in WK

Answer 11

MD of thalamus

mammillary bodies

Question 12

treatment of hypoglycemia in alcoholic patients

Answer 12

always give thiamine first, giving glucose without thiamine in a thiamine deficient patient can precipitate wernike’s

Question 13

vitamin B2

Answer 13

riboflavin

Question 14

reactions that riboflavin is involved in

Answer 14

oxidation/reduction

Question 15

FMN

Answer 15

NADH dehydrogenase (complex I)

Question 16

FAD

Answer 16

succinate dehydrogenase (complex II)

Question 17

riboflavin deficiency

Answer 17

cheilosis, corneal vascularization

Question 18

population that is at increased risk for riboflavin deficiency

Answer 18

neonates getting phototherapy (B2 degraded)

Question 19

vitamin B3

Answer 19

niacin

Question 20

amino acid from which niacin is derived, cofactor

Answer 20

tryptophan

B6 cofactor

Question 21

niacin deficiency

Answer 21

pellagra- diarrhea, dermatitis, dementia

Question 22

2 diseases that can cause niacin deficiency

Answer 22

hartnup disease (decreased tryptophan absorption) and carcinoid syndrome (increased tryptophan consumption for serotonin synthesis)

Question 23

vitamin B5

Answer 23

pantothenate

Question 24

B5 is a part of

Answer 24

CoA for acyl transfers and FA synthase

Question 25

unique symptom of B5 deficiency

Answer 25

adrenal insufficiency (due to decreased FA synthase activity)

Question 26

vitamin B6

Answer 26

pyridoxine

Question 27

3 general reactions B6 is needed for

Answer 27

amino acid synthesis heme synthesis transamination

Question 28

B6 deficiency (3)

Answer 28

peripheral neuropathy - dec NTs sideroblastic anemia - dec heme convulsions- dec GABA

Question 29

vitamin B7

Answer 29

biotin

Question 30

type of reaction that requires biotin

Answer 30

carboxylation (adding 1C)

Question 31

biotin deficiency

Answer 31

rare, related to raw egg white ingestion (avidin)- dermatitis, alopecia

Question 32

vitamin B9

Answer 32

folic acid

Question 33

main use of B9

Answer 33

purine/thymine synthesis- 1C transfers

Question 34

folate deficiency (2)

Answer 34

megaloblastic anemia no neuropathy *most common bit def in USA

Question 35

deficiency in pregnancy

Answer 35

neural tube defects

Question 36

b12 is a cofactor for (2)

Answer 36

- homocysteine methyltransferase (homocysteine --> methionine) - methylmalonyl-CoA mutase (methylmalonyl-coa --> succinyl-CoA)

Question 37

b12 deficiency symptom classes (2)

Answer 37

- megaloblastic anemia | - peripheral neruopathy

Question 38

why does B12 def cause megaloblastic anemia?

Answer 38

decreased homocysteine methyltransferase activity leads to decreased conversion of homocysteine to methionine = decreased THF = decreased dTMP pyrimidines

Question 39

why does B12 deficiency cause peripheral neuropathy?

Answer 39

increased methylmalonyl-CoA leads to defects in myelin

Question 40

schilling test

Answer 40

determine etiology of B12 deficiency, test B12 in urine (decreased B12 in urine indicates decreased absorption)

Question 41

infection that can cause B12 deficiency

Answer 41

diphyllobothrium latum

Question 42

general causes of B12 deficiency (3)

Answer 42

malabsorption lack of IF terminal ileum disease

Question 43

what is SAM?

Answer 43

product of methionine + ATP

Question 44

what is the role of SAM?

Answer 44

transfers methyl units

Question 45

what reaction is dependent on SAM?

Answer 45

conversion of norepinephrine to epinephrine

Question 46

role of vitamin C in collagen synthesis

Answer 46

cofactor for the hydroxylation of lysine and proline residues

Question 47

excess vitamin C increases the risk of toxicity from what metal? why?

Answer 47

iron toxicity, because it C puts iron in 2+ state making it more readily absorbed

Question 48

sites of hydroxylation for vitamin D

Answer 48

liver 25-OH | kidney- 1-OH

Question 49

why is hypercalcemia seen in sarcoidosis?

Answer 49

activated macrophages in granulomas increase vitamin D activation

Question 50

another name for vitamin E

Answer 50

a-tocopherol

Question 51

main role of vit E

Answer 51

antioxidant

Question 52

vit E deficiency

Answer 52

hemolysis and posterior column/spinocerebellar tract degeneration (mimics B12 but low MCV)

Question 53

role of vit K

Answer 53

catalyzes gamma carboxylation of clotting factors 2, 7, 9, 10, proteins C and S

Question 54

patients at risk for it K deficiency

Answer 54

neonates (no flora) | long term abx (depleted flora)

Question 55

what can decrease vit K in breast milk

Answer 55

antibiotics taken by mother, especially cephalosporins

Question 56

symptoms of zinc deficiency (4)

Answer 56

rash around face, mouth delayed wound healing abnormal sense of smell infertility in males