Nutrition

Question 1

Caisson’s Disease

Answer 1

Every 30 ft, increase 1 atm. Nitrogen gasses dissolved in tissue. If come up too quickly, bubbles = bends to stop blood flow.; Tx=hyperbaric O2.

Question 2

Anorexia

Answer 2

Distorted body image in anorexia -> dec. GnRH -> dec. FSH/LH -> amenorrhea + osteoporosis.

Question 3

Bulimia

Answer 3

No weight necessarily. BINGE eating + vomiting. Metabolic alkalosis -> respiratory acidosis (leading to hypoxia) -> PVC’s –> R on P -> Vfib; Mallory-Weiss or Borhaeve.

Question 4

Obesity

Answer 4

BMI = kg/m2. Main complication = HTN (unclear mech) -> LV hypertrophy -> HF; gall bladder; cancers (lots of aromatization of 17-steroids -> estrogens; endometrial ca, breast ca; colon ca

Question 5

Fat-soluble vitamins

Answer 5

ADEK, more likely to stored in fat —> greater chance for toxicities.

Question 6

Water-soluble vitamins

Answer 6

All co-factors for biochemical rxns.

Question 7

Vitamin A

Answer 7

Important for growth in children! (FTT). Visual (-dopsins) -> nictolopia (night blindness). Prevents squamous metaplasia (e.g. eye cuboidal -> white spots of metaplasia –> keratomalacia).

Question 8

Hypervitaminosis A

Answer 8

Big-game hunter eating bear livers. Cerebral edema. Papilledema -> HA (pseudotumor). Liver toxicity.

Question 9

Vitamin D deficiency

Answer 9

Sunshine is most way to get it. Not in breast milk. Reabsorbs Ca+ and phosphate in jejunum and needs to be hydroxylzed TWICE (1st in liver for 25, 2nd in kidney for 1-alpha-hydroxylase). PTH is responsible for synthesis of 1 alpha-hyroxylase (proximal tubule). Main f(X) = mineralization of bone and cartilage.

Question 10

Parathyroid

Answer 10

Reabsorption of Ca2+ (DCT at thiazide area) via a channel. On thiazides, leaves channel open for calcium to go in -> hypercalcemia. Decreases reabsorption of Phosphate and Bicarbonate at the PCT. Helps Vitamin D get 2nd hydroxylation in kidney. Alpha-hydroxylase

Question 11

Vit D + Parathyroid

Answer 11

Vit D gets to Osteoblast –> Release of alkaline phosphatase -> mineralization of cartilage and bone. You would think parathyroid receptor for osteoclast. Instead, calcitonin into osteoclast –> inhibition of it to stop bone resorption. PTH acts on osteoblast to release IL-1 (= osteoclast-activating factor) -> osteoclast breaks down bone to maintain calcium levels. Sex hormones check IL-1 (estrogen or testosterone).

Question 12

Vitamin D deficiency etios

Answer 12

Etios - lack of sunshine, poor diet, liver disease (increased CYP450 will dec. vitamin D). Phenytoin + OCP = not working OCP. Gamma-glutamyl transferase - enzyme of SER (revved up by drugs) –> increased Gamma-glutamyl transferase (pick up alcoholic), RENAL disease is most common (therefore CKD patients get 1,25-OH Vit D).

Question 13

Vit D deficiency drugs

Answer 13

Rickets and osteomalacia. Rickets - craniotabes (soft skulls), rachitic rosaries (excess of ostoid). Pathologic fx’s. Type 1 = missing alpha-1 hydroxyls. Type 2 = missing the receptor for vitamin D

Question 14

Hypervitaminosis D

Answer 14

Hypercalcemia -> hypercalcuria = stones

Question 15

Vitamin E

Answer 15

Maintains CELL MEMBRANE by preventing lipid peroxidation (via phospholipase), neutralizes oxidized LDL (very atherogenic).

Question 16

Deficient vitamin E

Answer 16

Very uncommon. CF patients w/ malabsorption of fat. (ADEK malabsorption). Hemolytic anemia (cell membrane). Posterior column disease, spinalcerebellar type diseases. Neuro + hemolytic.

Question 17

Vitamin E toxicity

Answer 17

1100 U. Prevents of synthesis of vitamin K dependent coagulant factors (1972, C&S). Anti-coagulated and synergistic in activity with warfarin.

Question 18

Vitamin K

Answer 18

Most of it is synthesized by COLONIC bacteria (anaerobes). Which is why we give Vit K to babies (isn’t in breast milk); to prevent hemorrhagic disease of the newborn. Usu. after 5 days, make their own b/c colonized. Made as K2 by bacteria. Converted to K1 (via Epoxide reductase - EPOXI glue). K1 gamma-carboxylates the Vit-K dept coagulation factors -> ACTIVATES them. They are the ones that need to be bound to Ca2+ to form a clot. The glutamic acid get carboxylated, allowing Ca2+ to bind those factors -> clot. Warfarin inhibits epoxide reductase (prevents K2 -> K1)

Question 19

Vitamin K deficiency

Answer 19

Broad spectrum antibiotics. Poor diet. Newborn. Malabsorption. Hemorrhagic diathesis.

Question 20

Vitamin C

Answer 20

Hydroxylates proline and lysine (Golgi apparatus) of collagen. Unstable blood vessels -> bleeding gums (lose you’re teeth); hemarthrosis. Perifollicular hemorrhage (red ring around the follicle). Corckscrew hairs. Glossitis. Cheilosis. (Ancillary tx for methhemoglobinemia)

Question 21

Excess Vitamin C

Answer 21

Renal stones. Increase in URIC acid and others. (Vit D also has stones when toxic).

Question 22

Thiamine deficiency

Answer 22

Thiamine is cofactor for Pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, alpha-ketoacid dehydrogenase, transketolase (Pentose shunt). ATP depletion. Dry beriberi = peripheral neuropathy (ATP needed for myelin), nystagmus. Wet beriberi = cardiomyopathy (biventricular; different from alcoholic cardiomyopathy). Most common cause is EtOH. *D5 -> glucose is used with thiamine -> subclinical thiamine deficiency -> neurological problem. Therefore should give in IV thiamine

Question 23

Niacin deficiency

Answer 23

Pellagra - Diarrhea, dermatitis (hyperpigmentation in sun-exposed areas), dementia. All the redox reactions w/ NADH. Tryptophan can be used to make niacin and serotonin. Nicotinic acid is least expensive lipid lowering drug (SE = flushing!) for familial combined hyperlipidemia.

Question 24

Riboflavin

Answer 24

FAD, FMN. Glutathione reductase req. riboflavin.

Question 25

Pyridoxine

Answer 25

Succinyl CoA + Glycine -(ALA synthase, B6)-> 1st step for HEME. Cytochrome system. Transaminase reactions (alanine is most abundant substrate in fasting state; from muscle; gluconeogenesis). Alanine -> pyruvate. Aspartate -> oxaloacetate. Neurotransmitter synthesis. Most common cause of deficiency = INH.

Question 26

Pantothenic Acid

Answer 26

FA synthase. Acetyl CoA.

Question 27

Biotin

Answer 27

Pyruvate carboxylase. 20 raw eggs/day -> binding of biotin. Rash and go bald. Fasting hypoglycemia (bad gluconeo), lactic acidosis (b/c pyruvate forced into lactate)

Question 28

Chromium

Answer 28

Glucose tolerance factor. Helps insulin do its job.

Question 29

Copper

Answer 29

Lysyl oxidase - cross-bridge for collagen fibers and elastic tissue. Weak collagen and weak elastin -> dissecting aortic aneurysm. Menkes.

Question 30

Flouride toxicity

Answer 30

Calcification in tendon

Question 31

Selenium

Answer 31

Glutathione peroxidase (requires Selenium). It’s an anti-oxidant b/c w/o it, glutathione cannot break down peroxidase.

Question 32

Zinc deficiency

Answer 32

Older person with dysgeusia = abnormal taste. Anosmia (can’t smell). Collagenase (req. Zn) -> breaks down Collagen III -> Collagen I. Therefore POOR wound healing = rash on face. Diabetics are Zn deficient.

Question 33

Dietary fiber

Answer 33

Insoluble and soluble. Soluble lowers cholesterol. Insoluble fiber sucks up water and bad things (lithocolic acid) into the interior of the colon for less contact

Question 34

Protein-restriction diet

Answer 34

For renal failure (prevent ammonia load), liver cirrhosis (bad urea cycle). Urease + bacteria make ammonia from urea in the colon.