21. Nutritional biochemistry Flashcards Preview

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Flashcards in 21. Nutritional biochemistry Deck (246):
1

What are the four proproteases secreted by the pancreas?

Tripsinogen
Chymotrypsin
Proelastase
Procarboxypeptidases

2

What are the active enzymes secreted by the pancreas?

Alpha-amylase
Lipases
Colipase
Phospholipases
Cholesterol esters
RNAase
DNAase

3

What is the key ion secreted by the pancreas?

HCO3-

4

What are the three stages of pancreatic secretion?

Cephalic
Gastric
Intestinal

5

What mediates pancreatic secretion in the cephalic phase?

Acetylcholine

6

What mediates pancreatic secretion in the gastric phase?

Acetylcholine
Gastrin

7

What mediates pancreatic secretion in the intestinal phase?

Cholecystokinin
Secretin

8

What is HCO3- secretion by pancreatic duct cells controlled by?

Acetylcholine
Secretin

9

What are the three types of lipase?

Lingual
Gastric
Pancreatic

10

Though lingual lipase and gastric lipase can act on their own, what does pancreatic lipase require for proper function?

Bile salts
Colipase

11

What are the three types of enzymes responsible for the digestion of fat?

Lipase (lingual, gastric, pancreatic)
Phospholipases
Cholesterol esterases

12

What components of fat can be taken up directly into an enterocyte?

Glycerol
Short chain fatty acids
Medium chain fatty acids

13

What components of fat are taken up in a mixed micelle?

Cholesterol
Lysophospholipids
Long chain fatty acids
Monoacylglycerols

14

What are the two main types of proteases?

Endopeptidases: cleaves in the center or proteins and peptides
Exopeptidates: cleaves from the N or C terminal ends of peptides and proteins

15

What is the endopeptidase in the stomach? What secretes it?

Pepsinogen--chief cells
**activated by acid and auto-activation

16

What synthesizes and secretes the endopeptidases of the duodenum and jejunum?

Alpha cells of the pancreas

17

How is the endopeptidase trysinogen activated?

Activated by epithelial enteropeptidase/enterokinase

18

What is chymorypsinogen and proelastase activated by?

Typsin

19

What are the two exopeptidases secreted into the duodenum?

Carboxypeptidases
Aminopeptidases

20

What synthesizes the exopeptidase carboxypeptidase vs aminopeptidase?

Carboxypeptidase: alpha cells of the pancreas
Aminopeptidase: intestinal epithelial cells

21

What are the three types of protein transporters found in the duodenum and jejunum?

Amino acid class specific
Dipeptide
Tripeptide

22

What are the two kinds of epithelial cell peptidases?

Tripeptidase
Dipeptidase

23

What enzyme digests carbs and is active in the oral cavity, early in the stomach?

Salivary alpha amylase

24

What enzyme disgests carbs and is acitve in the lumen of the duodenum?

Pancreatic alpha amylase

25

Where are the di and trisacchridases located?

Intestinal epithelial cell membranes (brush borders)

26

Where are carbohydrates absorbed?

Duodenum
Jejunum

27

What are the two transporters for the absorption of carbohydrates?

SGLT1
GLUT5

28

What are the sx of lactase deficiency? Cause?

Bloating and diarrhea due to the bacterial degradation of lactose (upon delivery to the large intestine undigested)

29

What gets removed in a typical RNY bypass of the small intestine?

Stomach
Duodenum
Part of the jejunum

30

What do calorie requirements depend on?

Energy expendature: BMR, thermal effect of food, physical activity

31

What are the two essential fatty acids?

Linoleic acid: w 3
Linolenic acid: w 6

32

What are the essential amino acids?

Arginine
Histidine
Isoleucine
Leucine
Lysine
Methionine
Phenylalanine
Threonine
Tryptophan
Valine

33

What has the highest calorie density of carbs, proteins, fat, alcohol

Fat 9kcal/gm
Alcohol 7 kcal/gm
Carbs 4kcal/gm
Proteins 4kcal/gm

34

What % of diet should carbs, proteins, and fat compose?

Carbs 45-65%
Proteins 10-35%
Fat 20-35%

35

6 causes of malnutrition

Poverty
Ignorance
Chronic alcoholism
Acute and chronic illness
Self-imposed dietary restriction
Other: GI disease, malabsorption syndrome, drugs, TPN

36

A malnourished child has a weight of less than __% normal

80%

37

What are the two protein storing compartments?

Somatic protein: skeletal muscle stores
Visceral protein: visceral organ stores

38

What is marasmus?

Severe reduction in caloric intake leading to >60% reduction in body weight

39

What protein compartment is depleted in marasmus?

Somatic protein compartment

40

What is the presentation of marasmus?

Growth retardation and loss of muscle mass
Emaciated extremities
Anemia and immunodeficiency

41

What protein stores are lost in Kwashiorkor?

Visceral protein stores

42

What causes Kwashiorkor?

Protein deprivation is greater than caloric deprivation
Protein malabsorption
Chronic protein loss: protein losing enteropathies, nephrotic syndrome, chronic diarrhea

43

Is albumin abnormal in Kwashiorkor or masasmus?

Kwashiorkor: hypoalbuminemia

44

What is the clinical presentation of Kwashiorkor?

Alternating hypo and hyperpigmented zones with desquamination
Hair color and texture changes
Fatty liver
Immune deficiency, anemia

45

What are the patient populations that frequently show malnutrition?

Chronically ill
Hospitalized
Advanced cancer
AIDS

46

Four complications of malnutrition:

Infection
Impaired wound healing
Sepsis
Death after surgery

47

How is the BMI calculated

BMI = weight (kg) / height (m2)

48

What are the key limitations to using BMI?

High muscle mass
High bone mass
Ranges change for children and teens

49

Two measurements for the % body fat?

Skinfold
Impedance

50

What are the characteristics of metabolic syndrome?

Obesity
Insulin resistance
Hypertriglyceridemia
Low HDL
Hypertension

51

What are the characteristic of type II diabetes?

Elevated blood sugars
Non-insulin dependent
Insulin resistance

52

How is type II diabetes controlled?

Weight loss
Exercise
+/- medications

53

What are the key medical complications of obesity?

Metabolic syndrome
Type II diabetes
Cardiovascular morbidity
Cholelithiasis
Cancers
PE/DVT
Obstructive sleep apnea
Hypoventilation syndrome
Osteoarthritis
Steatosis

54

What are the 4 Fs of cholelithiasis?

Femal
Fertile
Forty
Fat

55

What are the estrogen dependent cancers that are associated with obesity?

Endometrial hyperplasia/carcinoma
Breast cancer

56

What are the estrogen independent cancers that are associated with obesity?

Colon cancer
Kidney cancer
Esophageal cancer

57

Why is PE/DVT associated with obesity?

Estrogen is a RF for thrombosis

58

What are the three hyperlipidemias that are associated with accelerated, premature atheroscleorosis of the coronary arteries

Familial hypercholesterolemia
Hypertriglyceridemia
Familial combined hyperlipidemia

59

What is the "Recommended Dietary Allowance" (RDA)?

Average daily level of intake sufficient to meet the nutrient requirements of nearly all (97-98%) of healthy individuals

60

What is the definition of adequate intake?

Established when evidence is insufficient to develop an RDA and is set as a level assumed to ensure nutritional adequacy

61

What is a tolerable upper intake level?

Maximum daily intake unlikely to cause adverse side effects

62

What are 'daily values' used for?

Food and dietary supplement labels to indicate the percent of the recommended daily amount of each nutrient that a serving provides

63

What are the two general types of water soluble vitamins

Non B-complex
B-complex

64

What is the non-B complex water soluble vitamin?

Ascorbate (Vitamin C)

65

What are the three types of B-complex, water soluble vitamins

Energy releasing
Hematopoietic/1C metabolism
Amino acid metabolism

66

What are the energy-releasing, B-complex, water soluble vitamins?

Thiamine (B1)
Riboflavin (B2)
Niacin (B3)
Pantothenic acid (B5)
Biotin (B7)

67

What are the hematopoietic/1C metabolism, B-complex, water soluble viatmins?

Folate (B9)
Vitamin B12 (cobalamin)

68

What is the amino acid metabolism, B-complex, water soluble vitamin?

Vitamin B6 (pyridoxine, pyridoxamine)

69

What are the fat soluble vitamins?

Vitamin A (retinol, carotenes)
Vitamin D (cholecalciferol)
Vitamin E (tocopherols)
Vitamin K (phylloquinones)

70

Where are most B vitamins absorbed? What is the exception?

Duodenum and jejunum
B12 absorbed in the ileum and mircobiota-produced biotin in the large intestine

71

What are the sources of most B-vitamins

Meats
Milk
Whole grains and fortified breads/cereals
Legumes
Nuts
Green leaky vegetables

72

What are the sources of vitamin B12

Meat
Shellfish
Fish
Eggs
Milk, cheese, yogurt
**not available in plant products

73

What vitamin is thiamine pyrophosphate dependent on?

Thiamine

74

What vitamin is flavin adenine dinucleotide dependent on?

Riboflavin

75

What vitamin is nicotinamide adenine dinucleotide dependent on?

Niacin

76

Where is thiamine (B1) absorbed?

Duodenum
Jejunum

77

How long does it take for thiamine (B1) storage to be depleted

14 days

78

What is the active from of thiamine (B1)?

Thiamine pyrophosphate

79

What are three key functions of thiamine (B1)?

1. Cofactor for pyruvate dehydrogenase (decarboxylation)
2. Cofactor in the pentose phosphate pathway
3. Maintains neural membranes and normal nerve conduction

80

What are dietary sources of thiamine (B1)

Pork
Whole grains and fortified breads/cereals
Legumes and nuts

81

Who commonly gets thiamine (B1) deficiency?

Alcoholics

82

What are the three clinical syndromes of thiamine (B1) deficiency

1. Polyneuropathy--dry beriberi
2. Dilated cardiomyopathy--wet beriberi
3. Wernicke-Korsakoff syndrome

83

What are two possible treatments for thiamine (B1) deficiency

Banana bag (IV Mg, K, thiamine, folate)
Oral supplementation

84

What is Wernicke-Korsakoff Syndrome?

Reversible encephalopathy with opthalmoplegia, confusion and disorientation, nystagmus, and ataxia
Cause: Thiamine (B1) deficiency

85

What is the chronic stage of Wernicke Korsakoff syndrome?

Korsakoff syndrome: irreversible memory disturbances and confabulation

86

What is seen in the brain with Wernicke-Korsakoff syndrome?

Periventricular and mammilary body hemorrhage and necrosis

87

Is thiamine (B1) toxic?

Non-toxic--excess excreted

88

What vitamin is panthothenic acid

B5

89

Where is panthothenic acid (B5) absorbed?

Duodenum

90

Storage of pantothenic acid

Excess excreted, very little stored

91

What is the active form of panthothenic acid (B5)

Coenzyme A

92

What is the function of pantothenic acid (B5)

Carbohydrate and fatty acid synthesis
**acyl carrier protein function

93

What are good sources of panthothenic acid?

Whole grains
Meats
Fish
Poultry

94

Panthothenic acid deficiency ? Toxicity

Very rare
non-toxic

95

What vitamin is riboflavin

B2

96

Where is riboflavin (B2) absorbed?

Duodenum
Jejunum

97

What are the active forms of riboflavin

Flavin mononucleotide (FMN)
Flavin adenine dinucleotide (FAD)

98

What is the function of riboflavin (B2)

Electron carrier: complex dehydrogenases, citric acid cycle to the electron transport chain

99

What are good sources of riboflavin?

Milk and milk products
Eggs
Meat
Fish
Whole grains and fortified breads/cereals
Nuts and legumes

100

Who gets riboflavin (B2) deficiency?

Rare, except in alcoholics

101

What are the s/s of riboflavin (B2) deficiency?

Cheilosis: scaling and fissures at the mouth corners
Angular stomatitis: inflammation at the corners of the mouth
Glossitis: inflammation of the tongue
Dermatitis

102

Toxicity of riboflavin (B2)

non-toxic, excreted

103

What vitamin is niacin?

B3

104

Where is niacin absorbed?

Duodenum
Jejunum

105

What are the active forms of niacin (B3)

NADPH/NADP+
NADH/NAD+

106

When is NADH generated? Function?

Generated during degradation of carbs, fats, amino acids, nucleic acids
Carried electrons from the TCA cycle to the electron transport chain

107

When is NADPH generated? Function?

Glucose-6-phosphate dehydrogenase in the pentose phosphate pathway
Used in synthesis reactions for carbohydrates, fats, amino acids, and nucleic acids

108

What are good dietary sources of niacin (B3)

Meat
Fish
Milk
Eggs
Whole grains and fortified cereal/breads
Nuts and legumes

109

What is the name fore niacin or tryptophan deficiency?

Pellagra

110

Who gets pellagra (niacin or tryptophan deficiency)?

Alcoholics
People living in poverty

111

What are the three key sx of pellagra?

Dermatitis (when exposed to the sun)
Diarrhea
Dementia

112

What is the toxicity of niacin (B3) when given at pharmacological levels for hypercholesterolemia?

Flushing
Gastric irritation
Rashes

113

What vitamin is biotin?

B7

114

Where is biotin (B7) absorbed?

Duodenum
Jejunum

115

What is the active form of biotin (B7)?

Biotin bound to carboxylase

116

WHat is the function of biotin (B7)?

Carboxylase cofactor: pyruvate carboxylase and acetyl CoA carboxylase

117

What are dietary sources of biotin (B7)

Liver
Milk
Eggs
Fish
Peanuts
Chocolate
Whole grains
Legumes

118

Where in the body is biotin synthesized?

By intestinal bacteria

119

What can lead to biotin (B7) deficiency?

Rare, but more prevalent in the elderly
Can occur by binding of biotin to avidin in raw egg whites

120

What happens in a biotinidase deficiency?

Inability to convert dietary-derived biocytin to free biotin

121

What is the presentation of biotin deficiency in infants?

Poor growth
Neurological disorders

122

What is the presentation of biotin deficiency in infants and adults?

Dermatitis
Alopecia

123

Biotin toxicity?

None--excess is excreted

124

What vitamin is pyridoxine?

B6

125

Where is pyridoxine absorbed?

Jejunum and ileum

126

What is the active form of pyridoxine (B6)?

Pyridoxyl phosphate

127

What is the function of pyridoxyl phosphate?

Coenzyme involved in:
1. Amino acid degradation: aminotransferases, decarboxylases, serine hydroxymethyltransferase, aldolase
2. Glycogen degradation: glycogen phosphorylase
3. Porphyrin synthesis

128

Dietary sources of pyridoxine (B6)

Beans, nuts, leugmes
Meats
Eggs
Fish
Whole grains and fortified grains and cereals

129

Who gets pyridoxine (B6) deficiency?

Alcoholics
People with kidney failure
People on Isoniazid for tuberculosis

130

What are the sx of pyridoxine deficiency?

Cheilosis: scaling at the corners of the mouth
Angular stomatitis: inflammation at mouth corners
Glossitis: inflammation of the tongue
Dematitis
Peripheral neuropathy
Microcytic hypochromic anemia
Confusion and irritability

131

What is the toxicity of pyridoxine (B6)?

Peripheral sensory neuropathy

132

What are the two hematopoietic/1C metabolism vitamins?

Folate (B9)
Cobalamin(B12)

133

Where is folate (B9) absorbed?

Duodenum
Jejunum **
Ileum

134

What is the active form of folate (B9)?

Tetrahydrofolate

135

What is the function of folate (B9)

Carrier of 1C units for:
1. Purine synthesis
2. dTMP synthesis
3. Conversion of homocysteine to methionine for S-adenocylmethionine synthesis

136

Dietary sources of folate?

Beans and legumes
Citrus fruits
Dark, leafy green vegetables
Fortified grain and cereals
Meat

137

What are the 2 main causes of folate deficiency?

Inadequate intake
Antifolate treatment (methotrexate, 5-flurouracil)

138

What are the main sx of folate deficiency?

Megaloblastic anemia
Leukopenia
Fetal neural tube defects
Glossitis

139

What are the sx of spina bifida occulta, a neural tube defect that can occur with inadequate maternal folate intake?

Pain
Weakenss
Numbness in the legs and back

140

What is anencephaly?

Missing parts of the brain

141

How much supplementation of folate does the USPHS recommend?

400 ug dose daily

142

How is vitamin B12 (cobalamin) absorbed?

IF-B12 complex in the ileum

143

Storage of cobalamin (B12)

Liver
Storage lasts around 2 years

144

What are the only 2 biochemical rxns that require B12?

Methionine synthase
Methyl malonyl-conenzyme A mutase

145

What are good sources of B12?

Meat
Shellfish
Fish
Eggs
Milk and yogurt and cheese
**NOT PLANT PRODUCTS

146

What are some causes of vitamin B12 deficiency?

1. Impaired absorption: IF deficiency or ilieal resection
2. Increased requirement
3. Decreased intake (vegan)
4. Tapeworm (Diphyllobothrium)

147

What are the clinical s/s of B12 deficiency? (3)

1. Megaloblastic anemia (pernicious anemia)
2. Neural tube defects
3. Subacute combined neural degeneration: dorsal and lateral tract demyelination, parasthesias, spastic paraparesis, sensory ataxia

148

What are the three antioxidant vitamins?

Vitamin C
Vitamin E
Beta carotene (provitamin A)

149

What are the post-translational modificaiton vitamins?

Vitamin C
Vitamin K

150

Where is ascorbate absorbed?

Jejunum and ileum

151

What are the functions of ascorbate (vitamin C)

Antioxidant: reduces ROS
Cofactor of enzymes that reduce metal ions
Post-translational modification of proteins (collagens), lysyl and proyl hydroxylase
Synthesis of neurotransmitters and hormones

152

What are sources of ascorbic acid?

Fruits and vegetables
Highest in citrus fruits, strawberries, green peppers, broccoli, green leafy vegetables, tomatoes, potatoes

153

What happens with vitamin C defiency?

SCURVY
Impaired collagen formation: poor vessel support results in bleeding tendency, impaired wound healing, easy bruising, corkscrew hairs, and petechial hemorrhage

154

What are the fat-soluble vitamins?

Vitamin A (Retinol, Carotenes)
Vitamin D (Cholecalciferol)
Vitamin E (Tocopherols)
Vitamin K (Phylloquinones)

155

Where are fat soluble vitamins absorbed?

Duodenum
Jejunum

156

Where is vitamin D absorbed?

Duodenum and jejunum
ALSO the ileum

157

Where is vitamin K produced in the body?

Produced by microbiota in the large intestine

158

What vitamin is tocopherol?

Vitamin E

159

What is the most active form of vitamin E?

alpha-tocopherol

160

How is tocopherol (vitE) absorbed?

From micelles in the duo and jej

161

How is vitE, or tocopherol distributed in the body?

Chylomicrons

162

Where is tocopherol (vitE) stored?

Adipose tissue
Liver
Muscle

163

What is the function of vitamin E/tocopherol?

Antioxidant--scavengers free radicals

164

What are dietary sources of vitaminE/tocopherol?

Vegetable oils
Liver
Eggs

165

Incidence of vitamin E / tocopherol deficiency?

Uncommon, except for with malabsorption syndromes, TPN, and premature infants

166

What are the sx of tocopherol/vit E deficiency

Irritability
Edema
Hemolytic anemia

167

What is a pharmacological use of tocopherol/vitamin E

Alzheimer's disease progression inhibitor

168

What vitamin is phylloquinones?

Vitamin K

169

How is vitamin K absorbed?

From micelles into the duo, jej, ileum

170

How is vitamin K distributed in the body?

Chylomicrons

171

Where is vitamin K stored?

Liver

172

What is the active form of vitamin K?

Vitamin K1

173

What are the functions of vitamin K?

- Cofactor for vit K dependent gamma carboxylase (needed for factors II, VII, IX, X, S, C)
--> modified Gla residue binds Ca and localizes coagulation proteins on activated platelets

174

What are the dietary sources of vitamin K?

Green vegetables, spinach, kale
Peas
Cauliflower and cabbage
Synthesized by bacteria in the intestine

175

Though vitamin K deficiency is rare, what can cause it?

Warfarin tx
Malabsorption syndromes
Broad spectrum antibiotics (kills flora)
Lack of gut flora in neonates
Chronic liver disease

176

What are the sx of vitamin K deficiency?

Bleeding--defective clotting
->Easy bruising and hematomas
->Hemorrhagic disease of the newborn

177

What is seen in vitamin K toxicity?

Shortened bleeding time
**no toxicity with food as a source of the vitK

178

What vitamin are cerotenes and retinoids?

Vitamin A

179

Where is vitamin A stored?

Liver stellate (ito) cells
Retinyl esters

180

What is the function of beta carotene?

Antioxidant
Vitamin A precursor

181

What is the major transport form of vitamin A?

Retinol

182

What form of vitamin A is important for vision?

11-cis retinal (retinaldehyde)

183

What form of vitamin A is involved in the regulation of retinoid responsive gene expression--epithelilal cells function, mucous cell function, immunity, reproduction

Retinoic acid (all-trans, 9-cis)

184

How is 11-cis-retinal involved in vision?

Binds rhodopsin in rods and to cone pigments in cones: difference in binding to the three cone pigments results in absorption of different wavelengths of light
Light converts 11-cis retinal to all-trans-retinal

185

What happens with the conversion of 11-cis to all-trans retinal by light?

-The GPCR transducin in the rod and cone membranes changes conformation and activates the G-protein, activating a phosphodiesterase
-Cleavage of cGMP closes cGMP coupled ion channel, signal to brain

186

What are good sources of beta carotene?

Green leafy vegetables
Intensely colored vegetables like carrots, sweet potatoes, and red peppers

187

What are good sources of rentinyl esters?

Eggs
Meat
Dairy products

188

When is vitamin A deficiency seen in the US?

Poor intake with serious viral infections
Malabsorption syndromes
Liver cirrhosis

189

What is the clinical presentation of vitamin A deficiency?

Impaired vision--night blindness
Squamous metaplasia--mucus and epithelial cells
Renal, urinary calculi
Predisposition to pulmonary infections, diarrhea

190

What are some of the consquences of squamous metaplasia with retinoic acid deficinecy?

Xerophthalmia, Xerosis
Bitot's spots (keritin debris)
Corneal ulceration, keratomalacia
FOllicular hyperheratitis

191

Toxicity of beta carotene?

Non-toxic, but yellow skin due to fat deposition
**sclera not yellow

192

Toxicity of retinol

Toxic at high levels: blurred vision, abdominal pain, peeling of the skin, hair loss, headache, dizziness, vomiting, bone pain and deformities
Death if levels are high enough

193

Toxicity of retinal?

Toxic at high levels, esp to the retina

194

Toxicity of retinoic acid

Toxic at levels used to treat acne: teratogenic and peeling of the skin

195

What vitamin is calciferol?

Vitamin D

196

What are the two dietary forms of vitamin D?

Animals: D3, cholecalciferol
Plants: D2, ergocalciferol

197

What form of vitamin D can be synthesized in the skin

D2

198

What is the active form of vitamin D?

1,25 dihydrovitamin D (cholecalciferal)

199

Absorption of vitamin D?

Micelles to epithelial cells
Duodenum, jejunum, ileum

200

Where is vitamin D stored?

Liver

201

WHat is the function of vitamin D?

Controls the expression of vitamin D responsive genes
Maintains normal calcium and phosphate levels
Controls: cell cycle arrest, apoptosis, immune suppression, anti-inf, differentiation

202

What is the effect of vitamin D when calcium or phosphate is low

Increases absorption in the intestines
Decreases excretion by the kidney
Increases release by the bones

203

Sources of vitamin D/calciferols

Cheese
Butter and margarine
Fortified milk
Fish
Fortified cereals
**sunlight

204

What causes vitamin D deficiency?

Inadequate sunlight/dietary deficiency
Decreases absorption
Metabolic errors
End organ resistance
Phosphate depletion

205

What is the result of vitamin D deficiency in children

Rickets:
- bowed legs
- frontal bossing
- pigeon breast

206

What is the result of vitamin D deficiency in adults

Osteomalcia:
- soft, painful, bendable
- osteoporosis: loss of bone density, fragile bone
- Dowager's humb

207

What are s/s of vitamin D toxicity?

Diarrhea
Dermatitis
Headache
Nausea
Anorexia
Calcification of soft tissue
Decalcificaiton of bones
Kidney stones

208

Where are ions absorbed?

Stomach
Entire intestine

209

What form is iron absorbed in?

Fe2+

210

How is iron stored?

Ferritin and hemosiderin
In the liver, spleen, and bone marrow

211

Sources of iron

Meats
Fish
Shellfish
Lentils
Beans
Seeds
Tofu
Spinach

212

Function of iron

In heme as part of hemoglobin or myoglobin
Iron sulfer complexes in the TCA cycle, ETC
Enzyme cofactor

213

What is the most common nutritional deficiency?

Iron deficiency

214

Causes of iron deficiency

Inadequate diet, milk fed infants
Impaired absorption
Blood loss--GI and menstrual

215

What are the sx of iron defiicency?

Hypochromic, microcytic anemia
Impaired cognition and work capacity
Immune deficiency

216

What is the toxicity of iron?

Hemochromatosis
Abnormal deposition in the liver, pancreas, heart, and skin

217

Where is zinc absorbed?

Jejunum

218

What are sources of zinc?

Oysters and other shellfish
Meat
Plants

219

What are the functions of zinc

Component of enzymes involved in metabolism (oxidases, metalloproteinases)
Gene expression--Zn finger protein
Spermatogenesis
Skin maintenance and wound healing

220

Though incidence of zinc deficiency is rare, in what cases is it relatively common?

Diabetes mellitus
Malabsorption syndromes and chronic diarrhea
Renal disease and dialysis
IV feeding
Major burn patients
Inborn error of zinc absorption

221

What are the sx of zinc deficiency?

Rash
Anorexia
Diarrhea
Growth retardation
Depressed wound healing and immune response
Infertility due to inhibition of testosterone syn

222

What happens in zinc toxicity?

Inhibits copper absorption, leading to a copper deficiency

223

Where is iodine absorbed?

Stomach

224

What are sources of iodine?

Salt water fish and shellfish
Iodized NaCl

225

What is the main function of iodine?

Component of thyroid hormones

226

What are the sx of iodine deficiency?

Goiter
Cretinism: children with dwarfism, retardation, bone deformation, subnormal BMR)
Myxedema: adults with dry skin, swelling of the skin around nose and lips, mental deterioration, subnormal BMR

227

What ate sx of iodine tox?

Goiter
Thyrotoxicosis

228

Where is copper absorbed?

Stomach
Duodenum

229

What are the sources of copper?

Liver
Shellfish
Chocolate
Nuts
Seeds

230

Functions of copper

1. Oxidation rxns including e- transport: cyt C oxidase, tyrosinase
2. Neurotransmitter reg: dopamine beta oxidase
3. Antioxidants: superoxide dismutase
4. Collagen crosslinking enzymes: lysyl oxidase
5. Development of vascular and skeleton structures and the CNS

231

Though copper deficiency is rare, when do you see it?

Malnutrition
Excess zinc intake
Dialysis patients
Genetic diseases like Menke's syndrome

232

What are the sx of copper def?

Microcytic hypochromic anemia
Muscle weakness
Neurologic defects
Abnormal collagen crosslinks leading to bleeding
Neutropenia

233

When do you get copper toxicity?

Genetic disease--WD

234

What are the sx of copper tox?

Neurological defects
Kaiser Fleischer rings

235

Where is fluoride absorbed?

Stomach

236

What are the sources of fluoride?

Water (natural or supplemented)
Toothpaste

237

Functions of fluoride

Required by teeth

238

What happens with fluoride deficiency?

Dental caries

239

When does fluorine tox occur?

Kids eating fluorinated toothpaste

240

What are the sx of fluoride tox?

Mottled tooth enamel

241

Where is selenium absorbed?

Duo

242

Sources of selenium

Plants grown in selenium containing soil
Fish and shellfish

243

What are the functions of selenium

Component of glutathione peroxidase
Antioxidant with vitamin E
Regulates thyroid hormone action

244

Effects of selenium def

Myopathy
Cardiomyopathy (kids)

245

Selenium tox

Hair and hail damage
Tooth decay
Neuropathy
Liver cirrhosis
Depression

246

Name the ion:
1. oxygen transport and e metabolism
2. wound healing, spermatogenesis
3. antiox, e transport, collagen x linking, devo
4. dental health
5. antiox, thyroid hormone function

1. iron
2. zinc
3. iodine
4. copper
5. fluoride
6. selenium