Nutrition Flashcards
Caisson’s Disease
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.
Anorexia
Distorted body image in anorexia -> dec. GnRH -> dec. FSH/LH -> amenorrhea + osteoporosis.
Bulimia
No weight necessarily. BINGE eating + vomiting. Metabolic alkalosis -> respiratory acidosis (leading to hypoxia) -> PVC’s –> R on P -> Vfib; Mallory-Weiss or Borhaeve.
Obesity
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
Fat-soluble vitamins
ADEK, more likely to stored in fat —> greater chance for toxicities.
Water-soluble vitamins
All co-factors for biochemical rxns.
Vitamin A
Important for growth in children! (FTT). Visual (-dopsins) -> nictolopia (night blindness). Prevents squamous metaplasia (e.g. eye cuboidal -> white spots of metaplasia –> keratomalacia).
Hypervitaminosis A
Big-game hunter eating bear livers. Cerebral edema. Papilledema -> HA (pseudotumor). Liver toxicity.
Vitamin D deficiency
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.
Parathyroid
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
Vit D + Parathyroid
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).
Vitamin D deficiency etios
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).
Vit D deficiency drugs
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
Hypervitaminosis D
Hypercalcemia -> hypercalcuria = stones
Vitamin E
Maintains CELL MEMBRANE by preventing lipid peroxidation (via phospholipase), neutralizes oxidized LDL (very atherogenic).
Deficient vitamin E
Very uncommon. CF patients w/ malabsorption of fat. (ADEK malabsorption). Hemolytic anemia (cell membrane). Posterior column disease, spinalcerebellar type diseases. Neuro + hemolytic.
Vitamin E toxicity
1100 U. Prevents of synthesis of vitamin K dependent coagulant factors (1972, C&S). Anti-coagulated and synergistic in activity with warfarin.
Vitamin K
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)
Vitamin K deficiency
Broad spectrum antibiotics. Poor diet. Newborn. Malabsorption. Hemorrhagic diathesis.
Vitamin C
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)
Excess Vitamin C
Renal stones. Increase in URIC acid and others. (Vit D also has stones when toxic).
Thiamine deficiency
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
Niacin deficiency
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.
Riboflavin
FAD, FMN. Glutathione reductase req. riboflavin.
Pyridoxine
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.
Pantothenic Acid
FA synthase. Acetyl CoA.
Biotin
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)
Chromium
Glucose tolerance factor. Helps insulin do its job.
Copper
Lysyl oxidase - cross-bridge for collagen fibers and elastic tissue. Weak collagen and weak elastin -> dissecting aortic aneurysm. Menkes.
Flouride toxicity
Calcification in tendon
Selenium
Glutathione peroxidase (requires Selenium). It’s an anti-oxidant b/c w/o it, glutathione cannot break down peroxidase.
Zinc deficiency
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.
Dietary fiber
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
Protein-restriction diet
For renal failure (prevent ammonia load), liver cirrhosis (bad urea cycle). Urease + bacteria make ammonia from urea in the colon.
