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Flashcards in Vitamins Deck (45):
1

Vitamin A Use

Tx measles and AML: subtype APL (all trans retinoic acid)
Acne and wrinkles

2

Vitamin A deficiency

Night blindness
Dry scaly skin (xerosis cutis)
Corneal degeneration (keratomalacia)
Bitot spots (on conjunctiva)

3

Vitamin A excess

Acute: vertigo, blurred vision
Chronic: alopecia, hepatic toxicity, arthralgias, pseudo tumor cerebrum

4

Severe Vit A side effects

Teratogenic: negative pregnancy test and two forms of contraception before using isotretinoin

5

Fat soluble

Dissolves in fat: taken up by chylomicrons
More likely to be stored, greater chance of toxicity

6

Vitamin B1 Function

Thiamine
TPP used for: pyruvate dehydrogenase, alpha ketoglutarate dehydrogenase, transketolase
"ATP"

7

Vitamin B1 deficiency

Impaired glucose breakdown: (brain, heart affected first)
Wernicke-Korsakoff syndrome and beriberi (malnutrition and alcoholism)

8

Vitamin A Goljan

Big game hunter who has headaches

9

Wernicke-Korsakoff syndrome

Confusion, ophthalmoplegia, ataxia + confabulation
Damage to medial dorsal nucleus of thalamus and mammory bodies

10

Dry vs. wet beriberi

Dry: muscle wasting, foot drop
Wet: high output cardiac failure (biventricular dilation)

11

Diagnosis of B1 deficiency

Increased RBC transketolase activity following B1 administration

12

Vit B1 Goljan

Give IV thiamine before giving IV glucose in ER

13

Vitamin B2 function

Riboflavin: FMN
Redox reactions

14

Vit B2 deficiency

Cheilosis, corneal vascularization

15

Vitamin B3 function

Niacin
NAD/NADP

16

Vit B3 synthesis

Derived from TRYPTOPHAN
Need B2 and B6 (riboflavin and PLP)

17

Vit B3 use

Dyslipidemia: lower levels of VLDL and raises HDL
(Take Asa with niacin to prevent facial flushing: due to prostaglandins, not histamine)

18

Hartnup Disease

Autosomal recessive
Deficiency of neutral amino acid transporters in proximal renal tubular cells and on enterocytes
Decreased tryptophan-->pellagra like s/s.
Tx: high protein diet and nicotinic acid

19

Vit B3 deficiency

Glossitis
Pellagra: dermatitis (Broad collar rash), dementia and diarrhea
--hyperpigmentation of sun exposed limbs

20

Vit B5

Pantothenic acid
Component of Coenzyme A
Fatty acid synthase

21

Vitamin B6 function

Pyridoxine
Necessary for heme synthesis, transamination reactions and neurotransmitters (serotonin, epi, NorE, dopa, GABA)

22

Vit B6 deficiency

Convulsions, hyper-irritability, peripheral neuropathy
Inducible by ISONIAZID
Causes SIDEROBLASTIC ANEMIA

23

Vit B7

Biotin
Carboxylation enzymes

24

Vit B7 deficiency

Rare
Antibiotic use or raw egg white ingestion
Go Bald, dermatitis, enteritis

25

Vitamin B9

Folate
Converted to THF and used for 1 carbon methylation reactions
Synthesis of nitrogenous bases in DNA and RNA
Found in leafy green veggies
Absorbed in jejunum
Stored in liver

26

Vit B9 deficiency

Macrocytic, megaloblastic anemia
Hypersegmented neutrophils
Glossitis
No neuro s/s and NO elevation of methylmalonic acid
Increased homocysteine
MOST COMMON VIT DEFICIENCY IN THE US
May be drug induced: phenytoin, sulfonamides, methotrexate

27

Vit B12

Cobalamin
Cofactor for methionine synthase: transfer of methyl group onto homocysteine --> methionine
Found ONLY in animal products--vegans beware!

28

Vit B12 deficiency

Malabsorption: diphyllobothrium Latum, Sprue, enteritis
Lack of intrinsic factor: pernicious anemia, gastric bypass surgery
Absence of terminal ileum: surgical resection for Crohn's disease
insufficient intake: vegans

29

Vit B12 deficiency s/s

Macrocytic, megaloblastic anemia
Hypersegmented neutrophils
Paresthesias and SUBACUTE COMBINED DEGENERATION
Increased homocysteine and MMA

30

Vit C

Antioxidant
Hydroxylation of proline and lysine in collagen synthesis
Dopamine beta hydroxylase: concerts dopa to NorE

31

Vit C use

TX for methemoglobinemia : Fe3-->Fe2 (binds Oxygen, FERROUS)

32

Vit C deficiency

Scurvy: swollen gums, bruising, HEMARTHROSIS, peri follicular hemorrhages, corkscrew hair,
Weakened immune response

33

Vit C Goljan

old person on "tea and toast" diet will be deficient in Vit C

34

Vit C excess

N/v/d
Calcium palate nephrolithiasis -- STONES

35

Vit D

Increase intestinal absorption of calcium and phosphate, increased bone mineralization at low levels, increased bone resorption at higher levels

36

Vit D deficiency

Children: RICKETS, craniotabes-softening of skull bones
Adults: osteomalacia

Breastfed infants should receive ORAL Vit D

37

Vit D excess

Granulomatous disesae= SARCOID (increased activation of Vit D by epitheliod macrophages)
Hypercalcemia/uria = kidney stones!
Loss of appetite, stupor

38

Vit E

Tocopherol
Antioxidant (protects from free radical damage)
ENHANCES ANTICOAGULATION EFFECTS OF WARFARIN

39

Vit E deficiency

Hemolytic anemia, spinocerebellar tract demyelination-neuro presentation similar to Vit B12

40

Vit E toxicity

Prevents Vit K factor synthesis (if patient is also on warfarin, they become EXTREMELY ANTICOAGULATED!!)

41

Vit K

Cofactor for gamma carboxylate on of glutamic acid residues on various proteins required for blood clotting
Synthesized by intestinal flora
Necessary for protein C, S and factors 10, 9, 7, 2
Warfarin-Vit K antagonist

42

Vit K deficiency

Neonatal hemorrhage with increased PT and PTT, but NORMAL BLEEDING TIME
GIVE NEWBORNS VIT K INJECTIONS
May also occur after Ab use

43

Goljan Vit K

Rat poison = Vit K
Child gets into grandparent's warfarin= anticoagulated

44

Zinc function and deficiency

Transcription factor motifs
Delayed wound healing
Old person with abnormal taste and smell, acrodermatitis enteropathica (rash around eyes, mouth, nose and anus)

45

Vitamin A function

Retinal - antioxidant
Visual pigments
Differentiation of epithelial cells into specialized tissue