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121

Only vitamins with excess problems.

Vit A, Vit B3, Vit C, Vit D

122

Deficient B5?

Dermatitis, enteritis, alopecia, adrenal insufficiency

123

B6 f(x) and name?

Pyridoxine. Pyridoxal phosphate used for transamination, decarbox, glycogen phosphorylase. Neurotransmitter synthesis.

124

Deficient B6?

Peripheral neuropathy, sideroblastic anemia. Cheilosis, glossitis, dermatitis. INH --> B6 deficiency symptoms b/c chemically similar to pyridoxine and competes in synthesis of neurotransmitters while also increasing urinary excretion.

125

B7 f(x) and name?

Biotin. Cofactor for 1C adding rxns (acetyl-Coa carboxylase, pyruvate carboxylase, propionyl carboxylase)

126

Deficient B7?

Abx or excessive ingestion of egg whites. Dermatitis, alopecia, enteritis.

127

B9 f(x) and name?

Folic acid. Converted to THF for base synthesis. Absorbed in jejunum. Leafy green veggies. Small pool in liver.

128

Deficient B9?

Macrocytic, megaloblastic anemia. Inhibits dTMP synthesis. Glossitis, no NEURO. Dx - inc. homocysteine and normal methylmalonic acid. Tx w/ folate and thymidine.

129

B12 f(x) and name?

Cobalamin. Homocysteine methyltransferase (methionine pathway) and methylmalonyl-CoA mutase co-factor. Large reserve in liver.

130

Deficient B12?

Macrocytic, megaloblastic anemia. Parasthesias, subacute combined degen due to abnl myelin. UMN signs (lateral corticospinal dmg). Inc homocysteine AND methylmalonic acid. Buildup of methylmalonic acid -> myelin synthesis abnormalities. Etios - vegan, malasorption, lank of intrinsic factor, absence of terminal ileum

131

Vit C f(x) and name?

Ascorbic acid. Antioxidant, iron absorption, hydroxylation of collagen residues, dopamine -> NE.

132

Excess Vit C?

N/v, d, fatigue, calcium oxalate nephrolithiasis.

133

Deficient Vit C?

Scurvy - collagen syntehsis defect. Swollen gums, brusing, anemia, poor wound healing, corkscrew hair

134

Vit D f(x) and name?

D2 - (ergocalciferol from plants). D3 (cholecalciferon from milk). 1,25 = active form. Intestinal absorption of Ca+ AND phosphate. Inc. bone mineralization.

135

Deficient Vit D?

Rickets - bone pains and deformity. Osteomalacia (bone pain and weakness in adults).

136

Excess Vit D?

Hypercalcemia, hypercalciuria, loss of appetite, stupor. Scene in sarcoidosis.

137

Vit E f(x) and name?

Tocopherol/tocotrienol. Antioxidant for ERYTHROCYTES and membranes.

138

Deficient Vit E?

Hemolytic anemia, acanthocytosis (spiked RBCs), muscle weakness, posterior column and spinocerebellar tract demyelination. (Similar to B12 def except NO megaloblastic anemia and hypersegmented neutrophils)

139

Vit K f(x) and name?

Cofactor for carboxylation for Glu for Klotting. (1972, Canada-Sweden).

140

Deficient Vit K?

Neonatal bleeding (inc. PT and aPTT). Injection (guts can't absorb b/c sterile intestine).

141

Deficient zinc?

Delayed wound healing, hypogonadism, dec. adult hair, dysgeusia (Taste distortion)

142

Ethanol metabolism?

Alcohol dehydrogenase (cytosol); Acetalaldehyde dehydrogenase (mitochondria) producing acetate.
Limiting reagent is NAD+. Zero-order. Increases NADH/NAD+ ratio in liver ---> lactic acidosis, fasting hypoglycemia, hepatosteatosis)

143

What drugs affect ethanol metabolism pathway?

Disulfiram -| acetylaldehyde dehydrogenase.
Fomepizole inhibits alcohol dehydrogenase. Antidote for methanol or ethylene glycol poisoning.

144

Kwashiokor?

Protein deficient MEAL -> Malnutrition, Edema, Anemia, Liver (large b/c of fatty change 2/2 dec. apolipoprotein to move out VLDL). Also ascites.

145

Marasmus?

Total calorie malnutritions -> MUSCLE wasting.

146

What metabolic pathways occur in the mitochondria?

FA oxidation, acetyl-CoA production, TCA, oxidative phosphorylation; Parts of heme synthesis, urea cycle, and gluconeogenesis.

147

What metabolic pathways occur in cytoplasm?

Glycolysis, FA synthesis, HMP shunt, protein, steroid, cholesterol synthesis. Parts of heme, urea cycle, gluconeogenesis.

148

Net ATP production w/ glucose?

32 w/ malate-asp shuttle (heart and liver). 30 net w/ gylcerol-3-phosphate shuttle (muscle). 2 net if anaerobic.

149

Enzyme responsible for first step of glycolysis?

Hexokinase (most tissues) - high affinity, basal, feedback inhibited by glucose-6-P.
Glucokinase (liver, beta cells) - faster response, insulin induced, inhibited by fructose-6-P, implicated in MODY

150

Key enzymatic step of glycolysis? Regulation?

Phosphofructokinase-1 (PFK-1). Fructose-6-P -> Fructose-1,6-bisP. Inhibited by ATP, citrate, phosphoenolpyruvate. Activated by AMP and fructose-2-6-BP