Term
| What 3 things should all adequate diets provide? |
|
Definition
1) energy (carbs, fats, protein)
2) aa & FA (essential & non-essential)
3) vitamins/minerals |
|
|
Term
|
Definition
|
|
Term
def
secondary malnutrition |
|
Definition
| deficiency due to inadequate absorption, impaired usage/storage, excess loss, increased need |
|
|
Term
|
Definition
| deficiency or inadequacy of any or all nutrients needed in an adequate diet |
|
|
Term
|
Definition
| act as co-enzymes or hormones in vital metabolic pathways |
|
|
Term
| What are the 2 categories of vitamins? |
|
Definition
|
|
Term
| What are the fat soluble vitamins? |
|
Definition
|
|
Term
| What are the water soluble vitamins? |
|
Definition
|
|
Term
| What is required for dietary absorption of FS vitamins? |
|
Definition
| effective pancreatic & biliary function for dietary absorption |
|
|
Term
| What usually causes FS vitamin deficiency? |
|
Definition
| disturbances of fat absorption |
|
|
Term
| What causes WS vitamin deficiency? |
|
Definition
| primary or seconday malnutrition |
|
|
Term
| Are FS or WS vitamins found to have higher body stores? |
|
Definition
|
|
Term
|
Definition
| carotene family, retinal group |
|
|
Term
| What are the 4 normal functions of Vit A? |
|
Definition
1) component of visual pigment rhodopsin: retinal
2) maintain specialized epithelial differentiation (affects transcription of genes thru interation with DNA)
3) effects metabolism, inc. FA
4) resistance to infection & stimulation of immune system |
|
|
Term
| What are the dietary sources of Vit A? |
|
Definition
1) animal-derived products (fish, eggs, milk - retinol)
2) leafy green/yellow vegetables (carotenoids, β-carotene) |
|
|
Term
| Where is 90% of Vit A stored in the body? |
|
Definition
|
|
Term
| What is the storage form of Vit A? |
|
Definition
|
|
Term
| What is the visual pigment form of Vit A? |
|
Definition
|
|
Term
|
Definition
1) nyctalopia (night blindness)
2) squamous metaplasia & keratinization
a) eye: xerophtalmia (dry eye), keratomalacia (corneal ulceration), corneal clouding
b) skin & other epithelia: follicular hyperkeratosis
3) susceptibility to inf. (esp. measles)
4) predisposition to neoplasia (via squamous metaplasia) |
|
|
Term
| What causes nyctalopia in Vit A deficiency? |
|
Definition
| decreased rhodopsin in retinal rods & cones |
|
|
Term
|
Definition
|
|
Term
| What is the normal function of Vit D? |
|
Definition
| maintain plasma calcium & phasphate levels for adequate bone mineralization |
|
|
Term
| What are the sources of Vit D? |
|
Definition
| dietary: meat, dairy, additives (D2)
conversion: via UV light to D3 |
|
|
Term
| Where does Vit D travel to, once absorbed the gut or converted via UV? |
|
Definition
| Blood (has D-binding protein transporter) => liver |
|
|
Term
| What metabolism of Vit D occurs in the liver? |
|
Definition
| hydroxylation via 25-hydroxylase => 25-OH-D |
|
|
Term
| Where does 25-OH-D go once leaving the liver? |
|
Definition
|
|
Term
| What metabolism of 25-OH-D occurs in the kidney? |
|
Definition
| hydroxylation by 1-hydroxylase => 1,25(OH)2D |
|
|
Term
| What is the active form of Vit D? |
|
Definition
|
|
Term
| How does 1,25(OH)2D facilitate calcium & phosphate aborption in sm. bowel? |
|
Definition
| activating synthesis of calcium-binding proteins |
|
|
Term
| What are the possible Vit D deficency causes? |
|
Definition
1) malnutrition
2) malabsorption
3) chronic underexposure to sunlight
4) chronic liver diesaes
5) chronic renal disease
6) induction of CYP450
7) defective hydroxylase enzymes |
|
|
Term
| What diease is seen in Vit D deficiency in children? |
|
Definition
|
|
Term
| What disease is seen in adults with Vit D deficency? |
|
Definition
|
|
Term
|
Definition
- bowing deformities of wt-bearing long bones & spine
- overgrowth of cartilage at apiphyseal plates & ribs (rachitic rosary)
- other deformities |
|
|
Term
|
Definition
- decreaed bone density on radiographs
- osteoid excess
- minimal deformity
- susceptibility to microfractures |
|
|
Term
|
Definition
| bone is mineralized, but composed of thinner trabeculae |
|
|
Term
|
Definition
| bone density loss => wt-bearing areas brittle & susceptible to fracture (esp. hips & vertebral bodies) |
|
|
Term
|
Definition
|
|
Term
|
Definition
| cofactor for carboxylation rxns important in blood clotting |
|
|
Term
| What are the sources of Vit K? |
|
Definition
dietary: green, leafy vegetables
other: intestinal bacteria synthesis |
|
|
Term
Function
carboxylase Vit K is a cofactor for |
|
Definition
| converts glutamyl residues to γ-carboxyglutamates (provides calcium-binding sites) |
|
|
Term
Effect
carboxylase + Vit K cofactor |
|
Definition
| Allows interaction b/w clotting factors II, VII, IX, X (prothrombin family) & phospholipid surface necessary to generate thrombin |
|
|
Term
| What inactive form of Vit K is formed after use? |
|
Definition
|
|
Term
| How is Vit K epoxide recycled to active Vit K? |
|
Definition
|
|
Term
| How does Warfarin affect the Vit K cycle? |
|
Definition
| inhibits recycling of Vit K epoxide |
|
|
Term
| Why are Vit K deficencies rare? |
|
Definition
1) efficient recycling
2) interstinal flora provide ongoing source |
|
|
Term
|
Definition
| bleeding diathesis (=> hematoma, hematuria, melena, eccymoses, gingival bleeding, etc) |
|
|
Term
| What can cause Vit K deficency? |
|
Definition
1) neonates - absence of gut flora
2) diffuse liver disease - fat malabsorption
3) Abx - destruction of normal flora
4) warfarin therapy - inhibition of hepatic reductase |
|
|
Term
|
Definition
|
|
Term
| What is the dietary source of Vit E? |
|
Definition
|
|
Term
|
Definition
| anti-oxidant: inhibit formation of oxygen radicals |
|
|
Term
|
Definition
| phenol-like aromatic head attached to saturated hydrocarbon tail (allows molecule to "sit" in membrane lipid layers) |
|
|
Term
| How does Vit E protect from oxidation by free radicals? |
|
Definition
| Vit E is readily oxidized (takes lipid membrane place => protection) |
|
|
Term
| Why is it important to protect membranes from lipid peroxidation? |
|
Definition
| it's an autocatalytic charin rxn => single oxidation could propagate throughout the membrane |
|
|
Term
| Why is Vit E deficency rare? |
|
Definition
|
|
Term
| When can Vit E deficency occur? |
|
Definition
1) severe fat malabsorption
2) premature infants => low levels at birth combined with oxidative stress s.a. oxygen therapy |
|
|
Term
|
Definition
1) spinocerebellar degeneration
2) hemolytic anemia (esp. newborns)
3) increased susceptibility to ischemic heart disease |
|
|
Term
| What are the general properites of water soluble vitamins? |
|
Definition
1) sm. organic molecules
2) required in sm. amounts
3) used in universal energy utilization pathways
4) limited body stores easily depleted
5) deficency => systemic syndrome |
|
|
Term
|
Definition
|
|
Term
| What are the sources of thiamine? |
|
Definition
1) widely in nature (not in refined foods)
2) low intracellular reserves (muscle, heart & brain) |
|
|
Term
|
Definition
rxns where aldehyde groups are transferred
1) ATP sunthesis
2) pentose phosphate pathway
3) maintenance of normal nerve membranes/conduction |
|
|
Term
| Where in the world is thiamine primary malnutrition of thiamine common? |
|
Definition
| underdeveloped countries where diet consiss of processsed food |
|
|
Term
| What is the main source of thiamine defiency? |
|
Definition
| chronic alcoholism - inadequate diet or tansketolast abnormality |
|
|
Term
| What in thiamine deficiency affects cerebral function? |
|
Definition
| impiared glucose metabloism |
|
|
Term
| What in thiamine deficency impairs myocardial function? |
|
Definition
|
|
Term
| What 2 myocardial syndromes are seen in thiamine deficency? |
|
Definition
Dry Beri-beri
Wet Beri-beri |
|
|
Term
| What 2 cerebral syndromes are seen in thiamine deficency? |
|
Definition
| Wenicke & Korsakoff's syndromes |
|
|
Term
|
Definition
| myocardial failure with edema & vasodilation |
|
|
Term
|
Definition
peripheral neuropathy affecting lower extremities more than upper
affects motor, senory & reflex function |
|
|
Term
|
Definition
|
|
Term
Sx
Wernicke's encephalopathy |
|
Definition
eye movement abnormalities (nystagmus, ophthalmoplegia)
dysarthria
confusion
ataxia |
|
|
Term
|
Definition
retrograde amnesia
anterograde amnesia
confabulation |
|
|
Term
| What is the pathology of Wernicke & Korsakoff? |
|
Definition
| acute hemorrhagic necrosis of mammillary bodies & periventricular gray matter => atrophy |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| Why are deficencies of riboflavin, pyridoxine, & niacin rare? |
|
Definition
| widely present in common food sources |
|
|
Term
|
Definition
| Co-factor in energy pathways (FMN, FAD) |
|
|
Term
|
Definition
cofactor in transamination/decarboxylation rxns
needed for neurotranmitter systhsis and other synthetic pathways |
|
|
Term
|
Definition
| Co-factor in energy pathways (NAD/NADP) |
|
|
Term
| How do B2, B3, & B6 deficiencies manifest? |
|
Definition
| In organs with rapid turnover/active metabolism => abnormalities |
|
|
Term
Sx
B2, B3, B6 Deficiencies |
|
Definition
Epithelium (dermatitis, glossitis)
Bone marrow (anemia)
neural tissues (neuropathy, dementia) |
|
|
Term
|
Definition
| clinical syndrome of dermatitis, diarrhea, dementia from niacin deficency |
|
|
Term
| What is the first & most chariacteristic Sx of riboflavin deficency? |
|
Definition
| cheilosis (cracks & fissures @ edge of mouth) |
|
|
Term
|
Definition
|
|
Term
| What are the sources of Vit C? |
|
Definition
dietary: fresh leafy vegetables, tomatoes, citrus fruit
body store: depleted in 30-40 d without intake |
|
|
Term
|
Definition
1) anti-oxidant/free radical scavenger
2) biosynthesis
3) immune function
4) collagen cross-linking |
|
|
Term
| What happens to excess Vit C intake? |
|
Definition
|
|
Term
| What disease is seen in Vit C deficency? |
|
Definition
|
|
Term
|
Definition
1) bleeding tendency
2) slow/inadequate wound healing
3) children: skeletal changes (Moeller-Barlow disease: compare to rickets)
4) dermatologic change & frequent gingival/periodontal inf. |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
Function
B12 as a cofactor |
|
Definition
| 1) help enzyme generate FH4 (THF) from it's methylated form
2) aids conversion of methylmalonyl CoA ro succinyl CoA |
|
|
Term
| What is THF a co-enzyme for? |
|
Definition
| thymidylate synthetase (required for DNA precursor generation) |
|
|
Term
| What happens to THF in B12 deficency? |
|
Definition
| trapped in methylated form => THF deficency |
|
|
Term
| What happens when the succinyl pathway is interrupted by B12 deficency? |
|
Definition
| accumulation of methylmalonate & propionate => abnormal FA formation => membrane damage |
|
|
Term
| What is the Vit B12 source |
|
Definition
|
|
Term
| Why are primary B12 decfiencies rare (except in vegans/macrobiotic diets)? |
|
Definition
| storage reserves last for years |
|
|
Term
| What is the main source of B12 defiency? |
|
Definition
| malabsorption since the B12 absorption pathway is complex |
|
|
Term
|
Definition
| autoimmune diease resulting from production of auto-Ab to IF or gastric parietal cells (they synthesize & secrete IF) |
|
|
Term
|
Definition
| chronic inflammation of gastric lining epithelium => gastric gland atrophy, achlorhydria & intential metaplasia w/ atrophic glossitis |
|
|
Term
| What is the source of folate? |
|
Definition
| green vegetables, fruit, animal proteins |
|
|
Term
What type of folate decifency is common?
Why? |
|
Definition
secondary due to increased requirement resulting from increased DNA synthesis
1) pregnancy
2) infancy
3) hemolytic anemias
(or B12 deficency => B9 deficency) |
|
|
Term
| What drugs can inhibit folate absorption? |
|
Definition
Oral contrsceptives
Phenytoin |
|
|
Term
| What drugs can inhibit folate metabolism? |
|
Definition
|
|
Term
| What causes megaloblastic anemia? |
|
Definition
| insufficent B12/folate due to impaired DNA synthesis |
|
|
Term
| What happens to hematopoiesis in megaloblastic anemia? |
|
Definition
| nuclear-cytoplasmic dystrophy wtih immature nuclei lagging behind maturation => clinically ineffective hematopieosis |
|
|
Term
| What happens to RBCs & neutrophils in megaloblastic anemia? |
|
Definition
1) enlarged ovioid RBCs
2) hypersegmented neutrophils |
|
|
Term
def
subacute combined degeneration |
|
Definition
| Severe B12 deficency where myelin degeneration develops in posterior & lateral funiculi of SC |
|
|
Term
Sx
Subacute combined degeneration |
|
Definition
spastic paraparesis
sensory loss
painful paresethsias (itching, burning) |
|
|
Term
| What can happen in severe B12 deficency when treated with folate? |
|
Definition
anemia response
no neurological response |
|
|
Term
|
Definition
| minerals occuring at concentration <1 mg/gm |
|
|
Term
| What 3 things in the body is iron essential to the function of? |
|
Definition
1) hemoglobin
2) myoglobin
3) enzymes
~ 75% of all body iron is in these processes |
|
|
Term
| Why is iron absorption & storage availability tightly regulated? |
|
Definition
1) potential cellular toxicity
2) sequestered from pathogenic orgs
3) limited ability to dispose of increased stores |
|
|
Term
| What is the storage form of iron that's immediately accessible? |
|
Definition
|
|
Term
|
Definition
| iron aggregates without protein shell stored in lysosomes |
|
|
Term
| Where is iron absorption controlled? |
|
Definition
|
|
Term
| What does the liver secrete to inhibit the transfer of iron from mucosal cells to the plasma? |
|
Definition
|
|
Term
| How much of dietary iron is actually absorbed per day? |
|
Definition
|
|
Term
| What mediates iron transport in the blood? |
|
Definition
| transferrin => delivers to RBC precursors |
|
|
Term
| What happens to unused iron stores not transferred to the blood? |
|
Definition
|
|
Term
def
total iron binding capacity |
|
Definition
| potential serum iron level if all transferrin binding sites are completely occupied (usually ~1/3 TIBC) |
|
|
Term
| What can cause iron deficency? |
|
Definition
1) inadequate diet
2) infants/children (increased need, low dietary content)
3) chronic blood loss
4) impaired absorption |
|
|
Term
| What happens in iron deficency due to decreased heme synthesis? |
|
Definition
| microcytic-hypochromatic anemia |
|
|
Term
| What occurs in iron deficency due to decreased iron containing enzymes? |
|
Definition
1) nail changes
2) atrophic glossitis
3) esophageal webs |
|
|
Term
| What is Plummer-Vinson syndrome in iron deficency? |
|
Definition
| atrophic glossitis + esophageal webs + anemia |
|
|
Term
|
Definition
1) decreased serum ferritin
2) decreased bone marrow hemosiderin on biopsy
3) increased TIBC (due to increased transferrin)
4) decreased transferrin saturation |
|
|
Term
|
Definition
|
|
Term
|
Definition
| anemia & collagen defects |
|
|
Term
|
Definition
| chronic pain, cardiac disease |
|
|
Term
|
Definition
| susceptibility to tooth decay |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| How does iodine deficency cause goiter? |
|
Definition
| iodine deficency + inadequate production of thyroid hormone => TSH secretion => enlargement |
|
|
Term
|
Definition
impaired neurological development(cretinism)
myxedema (diffuse edema with slowing of mental/physical function) |
|
|
Term
| What can cause hypothyroidism besides iodine deficency? |
|
Definition
| disturbance in thyroid, pituitary, or hypothalamous |
|
|
Term
| What vitamins can be toxic? |
|
Definition
|
|
Term
|
Definition
1) teraogenesis
2) hepatic dysfunction
3) increased ICP (children)
4) if consume too many vegetables with β-carotene => non-toxic yellow skin |
|
|
Term
|
Definition
|
|
Term
|
Definition
| hypercalciruia => nephrolithiasis & metastatic calcifications |
|
|
Term
| What can cause iron toxicity? |
|
Definition
Diet
Increased RBS turnover
genetic disease
repeated blood transfusions |
|
|
Term
|
Definition
hemosiderosis (localized or systemic)
hemochromatosis (acquired or inherited) |
|
|
Term
| Where is protein-energy malnutrition seen? |
|
Definition
famine/war-torn areas
severely ill |
|
|
Term
| What are the 2 primary forms of protein-energy malnutrition? |
|
Definition
1) marasmus
2) kwashiorkor |
|
|
Term
| What are the 2 components of body protein? |
|
Definition
1) somatic (skeletal muscle)
2) visceral (organ stores) |
|
|
Term
What comparentment of preotein is depleted in marasmus?
kwashiorkor? |
|
Definition
|
|
Term
|
Definition
| deficency of protein AND energy (calories) |
|
|
Term
| What 2 mechanisms are used by the body to compensate for severe caloric restriction in marasmus? |
|
Definition
1) gradual metabolism of fat & muscle mass
2) dramatic reduction of energy utilization by reducing cellular ion pumps |
|
|
Term
| What is the main Sx in marasmus? |
|
Definition
|
|
Term
|
Definition
Atrophy of muscle mass & depletion of fat stores
Low metabolic activity
Growth rate decline
Mental & emotional impairment |
|
|
Term
| When is marasmus well compensated? |
|
Definition
|
|
Term
|
Definition
| Diet adequate in calories but deficent in protein => deficit in endogenous protein synthesis |
|
|
Term
|
Definition
edema
heptaomegaly
mental changes
hypermetabloic state
oxidative cellular damage
anemia
depigmentation of hair & skin (scaly/brittle) |
|
|
Term
| What causes edema in Kawshiorkor? |
|
Definition
| decreased plasma oncotic pressure |
|
|
Term
| What causes hepatomegaly? |
|
Definition
| fatty liver deposits due to inability to synthesize lipid carrier proteins |
|
|
Term
| Why is the hypermetabolic state of kwashiorkor maladaptive? |
|
Definition
| exacerbates already low fuel stores |
|
|
Term
| What causes oxidative cellular damage in kwashiorkor? |
|
Definition
imbalance in free radical producton/disposal exacerbated by:
1) inf.
2) sm. bowel bacterial overgrowth
3) selective deficency in antioxidant nutrients |
|
|
Term
| In which protein-energy malnutrition syndrome, which one do you see loss of appetite? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| When can patients develop cachexia? |
|
Definition
| terminal condition of chronic disease |
|
|
Term
| When can patients develop a kwashiorkor-like condition? |
|
Definition
| "line-fed" patients with inadequate protein intake |
|
|
Term
|
Definition
| excess accumulation of fat representing an imbalance b/w energy intake & expenditure |
|
|
Term
|
Definition
| central/upper accumulation |
|
|
Term
|
Definition
| peripheral/lower accumulation |
|
|
Term
| What happens to fat in obesity? |
|
Definition
| hypertrophy & hyperplasia |
|
|
Term
| What accounts for energy expenditure? |
|
Definition
70% - basal metabolic rate (BMR)
15% - thermic effect of food
15% - physical activity |
|
|
Term
| What are some medical conditions linked to obesity? |
|
Definition
medical school (lmao jk)
HTN
T2DM
metabolic syndrome
CVD
cancer
others |
|
|
Term
|
Definition
| abberant eating practices leading to disease or disability |
|
|
Term
|
Definition
|
|
Term
|
Definition
| binging followed by excessive means to reduce caloric intake (purging, excessive exercise) |
|
|
Term
|
Definition
disordered eating
amenorrhea
loss of bone density |
|
|
Term
|
Definition
|
|
Term
|
Definition
| underfeeding children to prevent future obesity, CVD, etc |
|
|
Term
| What complications are seen in AN? |
|
Definition
protein-energy malnutrition
anemia
depression |
|
|
Term
| What complications are seen in BN? |
|
Definition
demineralization of teeth
electrolyte imbalance
esophagus/stomach damage |
|
|
Term
def
iatrogenic nutritional disease |
|
Definition
| physician-induced malnutrition induced by therapeutic drugs |
|
|
Term
| What patients in the hospital must nutrition be monitored? |
|
Definition
1) Certain medical diseases
a) with medically relavent nutritional aspects
b) with substantial excretory loss of nutrients
c) with therapeutic intervention that induces malnutrition
2) ill/surgical patients (due to increased metabolism) |
|
|
