Brs Biochem 16/23

Front 1

Set 16 Q: Because UV light is required for the synthesis of its active form, deficiency of this fat-soluble vitamin is more likely to be found in northern latitudes, resulting in increased susceptibility to bone fractures (osteomalacia)

Back 1

Vitamin D - with exposure to UV light, the skin converts 7-dehydrocholesterol to cholecalciferol, which is first converted to 25-OH vitamin D in the LIVER and then to active 1,25 (OH)2 which acts on the cells of the KIDNEY and intestine to increase reabsorption of calcium, required for proper bone remodeling

Front 2

Set 16 Q: This disorder results in a failure to properly mineralize the matrix of type I collagen found in bone, resulting in weak bone formation in children during development.

Back 2

Rickets - a deficiency of vitamin D during childhood results in softening of the occipital and parietal bones (craniotabes), excess deposition of collagen along the costochondral junction (rachitic rosary), with depression of the chest along the diaphragm (Harrison's groove), and bowing of the legs (genus valgus/varus)

Front 3

Set 16 Q: Dietary supplementation with this antioxidant free-radical scavenging vitamin is associated with a decreased risk of coronary artery disease and delayed development of cataracts.

Back 3

Vitamin E - rarely, deficiency of the most active form of vitamin E (alphatocopherol) may result in oxidative damage to red blood cells due to increased fragility, degeneration of axons in the posterior columns of the spinal cord, and dying back axonopathy of the cells in the dorsal root ganglion. ***Deficiency of Vit E may mimic Freidrick's Ataxia: ataxia, DCML degeneration and peripheral nerve degeneration. Can distinguish by presenc eof kyphosis and high plantar arches in Freidrick's.

Front 4

Set 16 Q: A deficiency of this fat-soluble vitamin results in hemorrhagic disease, since it is required for the glutamyl carboxylation of several clotting factors.

Back 4

Vitamin K - Vitamin K is synthesized by intestinal microorganisms and is required for the production of clotting factors II, VII, IX, and X - Typical patient: new born baby or someone on coumadin

Front 5

Set 16 Q: A deficiency of this mineral results in defects in the production of thyroid hormone, with the development of symptoms of hypothyroidism

Back 5

Iodine deficiency - iodine is required for the production of both forms of thyroid hormone, T3 and T4; a deficiency of iodine results in impaired metabolism with weight gain, cold intolerance, constipation and slowed mentation.

Front 6

Set 16 Q: Impaired production of this substance results in defects in the absorption of vitamin B12 from the digestive tract

Back 6

Intrinsic Factor - intrinsic factor is produced by the parietal cells of the stomach fundus, which may be lost in cases of autoimmune pernicious anemia or gastric resection, resulting in a secondary deficiency of Vitamin B12

Front 7

Set 16 Q: This essential mineral is a vital component in the synthesis of hemoglobin as well as other metallo-enzymes

Back 7

Iron - iron deficiency results in defective hemoglobin production, leading to the development of a hypochromic microcytic anemia. - Besides general anemia symptoms of fatigue, pallor, CHF... iron deficiency anemia also present with spoon nails and dysphagia (from esophageal webs)

Front 8

Set 16 Q: This nutritional disorder, more prevalent in the western world, is characterized by self-induced weight loss secondary to limited food intake

Back 8

Anorexia Nervosa - those frequently affected include young, affluent white women who, in spite of an emaciated appearance often claim to be "fat." It is partially a behavioral problem; those afflicted are obsessed with losing weight. This is in contrast with bulimia where patients partake of binges of overeating followed by self-induced vomiting to avoid gaining weight. Most common cause of death in bulimia is mallory-weiss tear (painful vs esophageal varices which are painless)

Front 9

Set 16 Q: This nutritional disorder commonly occurs in children in third world countries where the diet, which is adequate in calories, is low in protein

Back 9

Kwashiorkor - a deficiency of dietary protein causes a decrease in protein synthesis that eventually affects the regeneration of intestinal epithelial cells; thus the problem is exacerbated by malabsorption. See Hepatomegaly and a distended abdomen (ascites from lack of protein in blood). - Contrast to marasmus which results from a diet deficiency in both protein and calories.

Front 10

Set 16 Q: This lipid-soluble vitamin is required for growth and differentiation as well as the production of the light-absorbing protein phodopsin, essential in vision

Back 10

Vitamin A - deficiency results in night blindness, dry eyes leading to corneal damage, and urinary stones. - Vitamin A toxicity causes the development of dry pruritic skin, cirrhosis of the liver, alopecia, sore throat, and increased intracranial pressure (papilledema, head aches) as well as vomiting; it is associated with excess dietary consumption of B-carotene.