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38 Cards in this Set
- Front
- Back
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Trace element that potentiates insulin action and results in glucose intolerance when deficient in the body. Biological role in glucose metabolism
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Chromium
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What is the mode of action of chromium in the body (hint: biochemistry)
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CrIII binds to transferrin in plasma
CrVI taken up by erythrocytes after absorption and reduced to CrIII within the cell. |
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Give two ways that chromium potentiates insulin action.
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1. directly by increase receptor # or affinity.
2. activation of other mediators such as insulin receptor kinase. |
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What are some signs of chromium deficiency in humans
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impaired glucose tolerance
elevated circulating insulin glucosuria elevated fasting blood glucose elevated serum triglecerides and cholesterol; encephalopathy, and neuropathy |
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what patient population is most at risk for chromium deficiency?
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Patients receiving long term total pareneral nutrition (TPN) if TPN fluids are not supplemented
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where is chromium absorbed in the body?
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GI tract
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What is the method of analysis used to evaluate chromium levels?
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GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROMETRY
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How is chromium excreted from the body?
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0.5ug chromium/L of urine
serum levels <0.5ug/L erythrocytes conc of 20 to 36 ug/L |
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A cofactor of oxidase enzymes, this trace element can be found 90%-95% on plasma bound to ceruloplasmin. Deficiency may result in inherited diseases such as wilsons and menkes
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copper
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Trace element that functions in energy productuin, iron metabolism, connective tissue formation, neurotransmetter metabolism
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copper
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bone density
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expressed in grams of minerals per area or volume of bone
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osteopenia
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the roentgenographic appearance of subnormally mineralized bone
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osteoid
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bone matrix
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parathyroid hormone
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regulates calcium levels in the blood
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phosphatonins
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class of phosphate regulating peptides that increase renal phosphorous excretion and inhibit 25-hydroxyvitamin D 1-alpha hydroxylase activity, reducing this causes intestinal phosphorous absorption
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cholecalciferol
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the parent vitamin D compound
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calcitonin
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hormone involved in calcium regulation
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calcidiol
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25-OHD produced when cholecalciferol is hydroxylated at the carbon-25-position in the liver
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cortical bone
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dense compact bone that provides structural support
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diaphysis
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shaft of long bone
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epiphysis
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end of long bone
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ionized calcium
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unbound divalent calcium ion that is biologically active
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metaphysis
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region in which the diaphysis and epiphysis converge
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n-telopeptides
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peptide fragments of the protein that link collagen fragments in bone
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osteoblasts
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cells that synthesize bone matrix
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osteocytes
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mature bone cells that have limited fxn and are encased in bone matrix, the composition of which they help to maintain
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osteolysis
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process of being able to resorb bone
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osteomalacia
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disorder in which bone contains normal amounts of osteoid but def. amounts of mineral
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osteoporosis
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generalized reduction in bone mass involving both mineral and osteoid
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rickets
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osteomalacia in childhood
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trabecular bone
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interlacing delicate spicules of bone that are predominantly involved in mineral homeostasis
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androgens and estrogens have what effect on bone formation? For thicker bone what does the body stimulate?
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increase bone formation and induce epiphyseal closure
androgen |
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Which hormone promotes epiphyseal growth ?
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growth hormone and IGF
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Nitrous oxide inhibits/stimulates osteoclasts.
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inhibits osteoclasts
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Leukotrienes inhibit/stimulate osteoclasts
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stimulate osteocasts
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with regards to parathyroid hormone (PTH) state whether increase or decrease in the following:
a. PTH is released in response to _a____ plasma calcium b. PTH ___ # and activity of osteoclasts c. PTH ____ calcium retention in kidney d. PTH _____ plasma Ca |
a. low plasma calcium
b. increases # and activity of osteoclasts c. increases calcium retention in kidneys d. increases plasma Ca |
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Hormone calcitriol (vitamin D) will cause:
inc/dec of : a. intestinal Ca absorption b. osteocalcin c.osteoclast activity |
a.increase intestinal Ca absorption
b. increase osteocalcin c.increase osteoclast activity |
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Calcitonin will inc/dec osteoclast activity
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calcitonin will decrease osteoclast activity
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