First Aid Biochem - Nutrition

Question 1

fat soluble vitamins

Answer 1

A,D,E,K
- toxicity with these vitamins is more common than with water-soluble vitamins due to accumulation of these vitamins in fat.

Question 2

water soluble vitamins

Answer 2

B1
B2
B3
B5
B6
B7
B9
B12
C

Question 3

B1

Answer 3

thiamine: TPP

Question 4

B2

Answer 4

riboflavin: FAD, FMN

Question 5

B3

Answer 5

niacin: NAD+

Question 6

B5

Answer 6

pantothenic acid: CoA

Question 7

B6

Answer 7

pyridoxine: PLP

Question 8

B7

Answer 8

biotin

Question 9

B9

Answer 9

folate

Question 10

B12

Answer 10

cobalamin

Question 11

C

Answer 11

ascorbic acid

Question 12

Storage of water soluble vitamins

Answer 12

all wash out from the body easily except for B12 and B9.
B12 - stored in lvier for about 3 - 4 years
B9 - stored in liver for about 3 - 4 months

Question 13

Vitamin A function

Answer 13

antioxidant, constituent of visual pigment, used in treatment of measles and AML subtype M3, essential for normal differentiation of epithelial into specialized tissue.
topically used for wrinkles and acne
found in liver and leafy vegetables

Question 14

Vitamin A deficiency

Answer 14

night blindness (nyctalopia), dry, scaly skin (xerosis cutis), corneal degeneration (keratomalacia)

Question 15

Vitamin A excess
acute toxicity
chronic toxicity

Answer 15

acute toxicity nausea, vomiting, vertigo, and blurred vision
chronic toxicity alopecia, dry skin, pseudotumor cerebri

teratogenic: cleft palate, cardiac abnormalities, negative pregnancy test and 2 forms of contraception required for acutane (isotretinoin) prescription.

Question 16

Vitamin B1 function

Answer 16

in thymine pyrophosphate (TPP) a cofactor for several dehydrogenase enzyme reactions

• pyruvate dehydrogenase (links glycolysis to the TCA cycle)
• alpha-ketoglutarate dehydrogenase (TCA cycle)
• transketolase HMP shunt
• branched-chain ketoacid dehyrdrogenase

Question 17

Vitamin B1 deficiency

Answer 17

impaired glucose breakdown (THIAMINE before IV glucose) –> ATP depletion
highly aerobic tissue affected first i.e brain and heart

Question 18

Wernicke-Korsakoff syndrome

Answer 18

- Thiamine B1 deficiency 
classic triad: 
confusion 
ophthalmoplegia 
ataxia 
\+ confabulation, personality change

Question 19

BeriBeri Syndrome

Answer 19

• Thiamine B1 deficiency
  Dry Beriberi - polyneuritis, symmetrical muscle wasting
  Wet beriberi - high-output cardiac failure, edema

Question 20

Vitamin B2 function

Answer 20

Riboflavin. component of flavins in FAD and FMN. Used as cofactors in redox reactions.

Question 21

Vitamin B2 deficiency

Answer 21

Riboflavin. Cheilosis (inflammation of the lips, scaling and fissures at the corners of the mouth), Corneal vascularitzation.
+ stomatitis, painful red tongue with sore throat.

Cheilosis and Corneal, the 2 C’s of B2.

Question 22

Vitamin B3 function

Answer 22

Niacin. constituent of NAD+, NADP+ used in redox reactions. Derived from tryptophan. Synthesis requires B2 and B6. Used in the treatment of dyslipidemia, lowers VLDL and raises HDL.

Question 23

Vitamin B3 deficiency

Answer 23

Niacin.
Glossitis.
Severe deficiency leads to pellagra, can be caused by:
- Hartnup disease (own card)
- malignant carcinoid (increased tryptophan metabolism)
- isoniazid (decreases vitamin B6)

Symptoms of pellagra:
- Diarrhea, Dementia (and hallucinations), Dermatitis(C3/C4 dermatome, broad collar rash)

Question 24

Hartnup Disease

Answer 24

autosomal recessive deficiency of neutral amino acid (i.e. tryptophan) transporters in the proximal renal tubular cells and on enterocytes
–> neutral amino acuduria
–> decrease tryptophan for conversion to niac in
–> pellagra like symptoms
Tx: is high protein diet and nictonic acid

Question 25

Vitamin B5 function

Answer 25

pantothenic acid. an essential component of coenzymeA.

Question 26

Vitamin B5 deficiency

Answer 26

dermatitis, enteritis, alopecia, adrenal insufficiency.

Question 27

Vitamin B6 function

Answer 27

pyridoxine. converted to PLP (pyridoxal phosphate), a cofactor used in transamination (i.e. ALT, AST), decarboxylation reactions, glycogen phosphorylase. Used in the synthesis of niacin and neurotransmitters including norepinephrine, epinephrine, serotonin, dopamine, GABA.

Question 28

Vitamin B6 deficiency

Answer 28

convulsions, hyperirritability, peirpheral neuropathy, deficiency is inducible by isoniazid and oral contraceptive, sideroblastic anemia due to impaired hemoglobin synthesis and iron excess.

Question 29

Vitamin B9 function

Answer 29

folate. converted to THF, a coenzyme for 1 carbon transfer/methylation reactions. IMPORTANT for the synthesis of nitrogenous bases in DNA and RNA. found in leafy green vegetables, absorbed in jejunum. 3-4 month reserve in the liver.

Question 30

Vitamin B9 deficiency signs/symptoms labs causes

Answer 30

folate. macrocytic megaloblastic anemia, hypersegmented PMNs, glossitis, NO NERUOLOGIC symptoms (this is in contrast to B12) Labs: increase homocysteine (normal methymalonic acid also in contrast to B12). MOST COMMON vitamin deficiency in the united states seen in alcoholism and pregnancy. Can be caused by certain drugs: phenytoin, sulfonamides, methotrexate.

Question 31

Vitamin B12

Answer 31

cobalamin.

Question 32

Vitamin B12 function

Answer 32

cobalamin. cofactor for methionine synthase (transfers CH3 groups as methylcobalamin) and methylmalonyl-CoA mutase. Found in animal products. Very large reserve pool in the liver. - Note anti-intrinsic factor antibodies are diagnostic for pernicious anemia.

Question 33

Vitamin B12 Deficiency signs/symptoms causes labs

Answer 33

macrocytic, megaloblastic anemia, parethesias, degeneration of dorsal column, lateral corticospinal tract, and spinocerebellar tracts. cobalamin. Deficiency is caused usually by malabsorption (sprue, enteritis), lack of intrinsic factor (pernicious anemia, gastric bypass surgery), absence of terminal ileum (i.e. after surgical resection for crohn disease), or insufficient intake (vegan). increased homocysteine and methylmalonic acid.

Question 34

Vitamin C function

Answer 34

ascorbic acid.

Question 35

Vitamin C function

Answer 35

ascorbic acid. antioxidant. also facilitates iron absorption by reducing it to Fe2+ state. it is necessary for hydroxylation of proline and lysine in collagen synthesis. necessary for dopamine b-hydroxylase which converts dopamine to NE.

Question 36

Vitamin C deficiency

Answer 36

Scurvy. Swollen gums, bruising, petechiae, hemarthrosis, anemia, poor wound healing, perifollicular and subperiosteal hemorrhages. "corkscrew hair". weakened immune response. Vitamin C causes sCurvy due to a Collagen synthesis defect.

Question 37

Vitamin D function | sources

Answer 37

D2 = ergocalciferol ingested in plants. D3 = cholecalciferol consumed in milk, formed in sun exposed skin (stratum basale) 25-OH D3 - storage form 1,25-OH D3 - calcitriol, active form - function: increases intestinal absorption of calcium and phosphate, increased bone mineralization at low levels, increased bone resorption at higher levels.

Question 38

Vitamin D deficiency

Answer 38

Rickets in children, bone pain deformity. Osteomalacia in adults (bone pain and muscle weakness) hypocalcemic tetany

Question 39

Vitamin D excess

Answer 39

hypercalcemia, hypercalciuria, loss of appetite, stupor. Seen in granulomatous disease (there is increased activation of Vitamin D by epitheliod macrophages).

Question 40

Vitamin E function

Answer 40

antioxidant. protects RBCs and membranes from free radical damage.

Question 41

Vitamin E deficiency

Answer 41

Hemolytic anemia, acanthocytosis, muscle weakness, posterior column and spinocerebellar tract demyelination. - Neurologic findings may be similar to B12, but there will not be associated megaloblastic anemia, hypersegmented neutrophils, or increased serum methymalonic acid.

Question 42

Vitamin K function

Answer 42

Cofactor for gamma-carboxylation of glutamic acid residues on various proteins required for blood clotting. Synthesized by intestinal flora. - necessary for maturation of the clotting factors 2,7,9,10 as well as protein C and protein S. Warfarin is a vitamin K antagonist.

Question 43

Vitamin K deficiency

Answer 43

Neonatal hemorrhage can present with increased PT and increased aPTT but normal bleeding time (neonates have sterile intestine and lack bacterial flora that make vitamin K, coagulation factors cannot mature). Hemorrhage from vitamin K deficiency can also occur after prolonged use of antibiotics. - NOTE vitamin K is not in breast milk. neonates are given vit K injection to prevent hemorrhage in newborn.

Question 44

Zinc function

Answer 44

an essential mineral for the activity of >100 enzymes.

Question 45

Zinc deficiency

Answer 45

delayed wound healing, hypogonadism, decrease adult hair (axillary, facial, pubic), dysgeusia, anosmia, acrodermatitis enteropathica

Question 46

Kwashiorkor cause presentation

Answer 46

protein malnutrition resulting in skin lesions. edema (due to decreased plasma oncotic pressure), liver malfunction (fatty changes due to decresed apolipoprotein syntehsis). clinical picture is small child with swollen abdomen.