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| 6653030935 | Vitamin B12 | Found exclusively in foods of animal origin due to microbial synthesis or prior ingestion of the vitamin | 0 | |
| 6653138930 | Vitamin B12 structure | corrin ring with cobalt incorporated into the center | 1 | |
| 6653147551 | Three coenzyme forms of vitamin B12 | Methyl, hydroxyl, and deoxyadenosyl-cobalmin | 2 | |
| 6653155483 | Cyanocobalamin | form of vitamin B12 used in supplements and fortified foods | 3 | |
| 6653161010 | Methyl and deoxyadenosyl-cobalamin | the two biologically active forms of vitamin B12; all forms are readily converted into these biologically active forms | 4 | |
| 6653179516 | Impaired Vitamin B12 bioavailability | an excess intake of vitamin C > 500 mg/day | 5 | |
| 6653187701 | Haptocorrin | a glycoprotein that binds free b12 and is secreted by salivary glands and swallowed with food; also called R-protein and transcobalmin I (TC-1) | 6 | |
| 6653205153 | B12 gastric digestion | released from protein ingested via the action of HCl and pepsin in the gastric secretions | 7 | |
| 6653219278 | B12 complex intestinal digestion | Transcobalamin I (TC1) complex travels into the small intestine where pancreatic proteases hydrolyze haptocorrin or R protein and free B12 is released | 8 | |
| 6653233385 | Intrinsic factor | A glycoprotein produced by gastric parietal cells and forms complex with B12 in the duodenum; moves to ileum | 9 | |
| 6653252802 | Cubulin | intrinsic factor receptor in the ileum where IF-B12 complex is absorbed; on GI epithelial cells | 10 | |
| 6653261519 | TC-II | Vitamin B12 transporter protein after intestinal absorption; enters portal circulation, taken up first by liver, then bone marrow and erythrocytes | 11 | |
| 6653273149 | Vitamin B12 storage | unlike other water-soluble vitamin, b12 can be stored in the liver | 12 | |
| 6653283929 | B12 secretion | Vitamin B12 is secreted into the bile so most is reabsorbed via enterohepatic circulation | 13 | |
| 6653295436 | Those at risk for B12 deficiency | Pancreatic insufficiency interferes with release of free b12, impaired HCl production, elderly, H2 antagonists or PPIs, removal of a portion of stomach, ileal resection, chronic malabsorption syndromes | 14 | |
| 6653310211 | Methylcobalamin | cofactor for methionine synthetase which converts homocysteine to methionine | 15 | |
| 6653315550 | Methyl trap | when b12 is lacking, 5-methyl-THF becomes trapped in its inactive form | 16 | |
| 6653325201 | Deoxyadenosyl-cobalamin | form of vitamin B12 required for the conversion of methylmalonyl coenzyme A to succinyl coenzyme A Also required for the degradation of certain amino acids and odd chain fatty acids | 17 | |
| 6653344066 | RDA for B12 ages 14 and up | 2.4 micrograms | 18 | |
| 6653348518 | Food sources of Vitamin B12 | Fortified cereals, meat, fish, poultry, eggs | 19 | |
| 6653373566 | Signs of B12 deficiency | cognitive decline, cardiovascular disease, bone fractures, megaloblastic anemia with macrocytosis, neutrophil hypersegmentation, bone marrow changes, leukopenia, thrombocytopenia; glossitis, constipation, diarrhea; hand and feet paresthesia, decline of vibration and/or position sense, unsteadiness, confusion, depression, mental slowness, poor memory; delusions and overt psychosis | 20 | |
| 6653395783 | B12 toxicity | no toxicity known | 21 | |
| 6653398934 | Normal B12 | 24.4-100 ng/dL serum B12 | 22 | |
| 6653411528 | B12 deficiency: in general | hematologic, GI, and neurological manifestations | 23 | |
| 6653413109 | B12 deficiency in aging | cognitive decline, cardiovascular disease, and bone fractures | 24 | |
| 6653417964 | B12 deficiency in malabsorption | Gastrectomy, gastric bypass, ileal resection, Crohn's disease; also in vegetarian populations; reduced HCl production; overgrowth of H.pylori | 25 | |
| 6653429635 | Stage I Vitamin B12 deficiency | low serum vitamin B12 | 26 | |
| 6653435524 | Stage II Vitamin B12 deficiency | Low cell stores of vitamin B12 | 27 | |
| 6653436952 | Stage III vitamin B12 deficiency | A biochemical deficiency | 28 | |
| 6653439300 | Stage IV vitamin B12 deficiency | A clinically apparent deficiency | 29 | |
| 6653445145 | Serum holotranscobalamin II | earliest indicator of a compromise in b12 status | 30 | |
| 6653452863 | When B12 levels are normal in deficiency | serum vitamin b12 can remain normal at the expense of cellular stores | 31 | |
| 6653459214 | Serum methylmalonic acid (MMA) and serum homocysteine | these levels are elevated in greater than 90% of individuals with B12 deficiency | 32 | |
| 6653464387 | Serum B12 | procedure of choice for determining b12 status | 33 | |
| 6653471091 | Treatment for B12 deficiency | 100 or 1000-mcg IM injections at 1 month intervals until corrected; more frequently in symptomatic B12 deficiency | 34 | |
| 6653505202 | Vitamin B12 recommendation for vegetarians | standard MVI | 35 | |
| 6653506282 | Normal serum MMA | 0.08 to 0.56 micromol/L | 36 | |
| 6653508804 | Normal homecysteine level | 5-15 micromol/L | 37 | |
| 6664713913 | Thiamine | consists of a central carbon to which a nitrogen-containing ring and sulfur-containing ring are attatched |  | 38 |
| 6664732996 | Biologically active coenzyme of thiamin | Thiamin pyrophosphate (TPP) also known as thiamin diphosphate | 39 | |
| 6664750196 | Thiamine digestion | before absorption, intestinal phosphatases hydrolyze the phosphates, leaving the free version | 40 | |
| 6664767302 | Thiamine absorption | Mainly absorbed in the proximal small intestine, especially the jejunum, via a carrier mediated process. Absorption is passive with high intakes | 41 | |
| 6664796813 | Most common cause of impaired thiamine absorption | Alcohol abuse | 42 | |
| 6664802074 | Blood thiamine | Bound to albumin in the blood; majority of thiamine present in red bloods cells existing as TDP | 43 | |
| 6664825119 | Key biological functions of thiamine | Energy transformation, synthesis of pentoses and NADPH, and membrane and nerve conduction | 44 | |
| 6664847563 | Magnesium-coordinated activity of thiamine | TDP is a conenzyme for the oxidative decarboxylation of alpha-keto acids (pyruvate and alpha-ketoglutarate) which are involved in carbohydrate metaboism | 45 | |
| 6664881722 | Transketolase | thiamine is a cofactor for this enzyme in the pentose phosphate pathway | 46 | |
| 6664897154 | Thiamine: major causes of deficiency | Patients with recurrent vomiting, gastric surgery, alcoholism, or those with increased demand with marginal nutritional status; refeeding syndrome, dialysis, hyperemesis gravidarum, long-term PN | 47 | |
| 6664921934 | Time for thiamine deficiency to occur | A deficiency can occur within 14 days without adequate intake or increased demand | 48 | |
| 6664934154 | Standard prophylactic dose of thiamin | 5-20 mg/d parenteral thiamine. Wider ranges between 50-300 mg/d (IV, IM, or oral) have been advocated | 49 | |
| 6664967509 | Wernicke's encephalopathy: triad of symptoms | ocular abnormalities, gait ataxia, mental status changes | 50 | |
| 6664984041 | Deficiency develops rapidly | Thiamine is usually first nutritional deficiency noted when food intake is limited or when absorption is impaired with alcohol abuse because deficiency develops rapidly | 51 | |
| 6664998385 | Body stores of thiamine | 30 mg | 52 | |
| 6665009286 | Untreated thiamine deficiency | Results in fatal lactic acidosis | 53 | |
| 6665016667 | Bariatric Beriberi | acute postgastric reduction surgery neuropathy; occurs alongside b12 deficiency | 54 | |
| 6665026182 | Thiamine lab assay | Erythrocyte transketolase activity with and without the in vivo addition of TDP | 55 | |
| 6665032076 | Normal transketolase | 0-15%: acceptable thiamine status | 56 | |
| 6665039569 | Low transketolase | stimulation of 16-24 % marginally deficient | 57 | |
| 6665047526 | Deficient transketolase | stimulation greater > 25 % indicates high risk of deficiency | 58 | |
| 6665052617 | Thiamine whole blood | values < 1.7 mcg/dL denote deficiency | 59 | |
| 6781167839 | Cheilosis | Riboflavin, B6, Iron, ? zinc |  | 60 |
| 6781172144 | seborrheic dermatitis | Riboflavin (face and scrotum); B6 |  | 61 |
| 6781178127 | Glossitis | Riboflavin, B6, iron |  | 62 |
| 6783248044 | Form of B6 in animal products | Pyridoxal (PL) and pyridoxial phosphate (PLP) | 63 | |
| 6783250671 | Form of B6 in plants (more stable form) | Pyridoxine | 64 | |
| 6783256926 | What extrahepatic tissue contains the most PLP? | Muscle, 75-80% | 65 | |
| 6783259330 | What is the excreted form of vitamin B6? | 4-pyridoxic acid | 66 | |
| 6783262278 | Plasma B6 | 60% of B6 is present as PLP bound to albumin for transport AND hemoglobin in the enterocyte | 67 | |
| 6783266891 | b6 enzymatic reactions | protein, amino acid, and lipid metabolism; gluconeogenesis; steroid receptor binding; central nervous center development; neurotransmitter synthesis, heme biosynthesis; normal immune function | 68 | |
| 6783279033 | B6 deficiency post intestinal transplant | neuropmyopathic disorder associated with progressive muscle weakness and gait disturbances; PLP deficiency | 69 | |
| 6783283506 | Lhermite sign | related to low B6 intake; affects the spinal cord | 70 | |
| 6783287302 | B6 intake associated with negative effects | prolonged intake > 300 mg/day | 71 | |
| 6783289739 | UL for B6 19 years and older | 100 mg/day | 72 | |
| 6783294142 | RDA B6 14-50 years of age | 1.3 mg/day | 73 | |
| 6783295321 | RDA > 50 years of age b6 | 1.7 men; 1.5 females mg/d | 74 | |
| 6783340294 | Function of Biotin | Functions as cofactor for four carboxylase enzymes in mammalian systems (transports carbon dioxide to various substrates) | 75 | |
| 6783351386 | Biotin is a cofactor for which carboxylases | acetyl-coenzyme A carboxylase, pyruvate carboxylase, propionyl-CoA carboxylase and 3 methlycrotonyl-ClA carbyoxylase | 76 |
