Term
| Recommended macronutrient distribution of diet |
|
Definition
30% fat
15% proetin
55% carbohydrates |
|
|
Term
size of RBC's in folate or B12 deficiency:
Why? |
|
Definition
Large RBC's
Cells can not divide due to decreased purines/pyramidines |
|
|
Term
size of RBC's in iron deficiency?
Why? |
|
Definition
smaller
-there is no shortage of DNA as there is in folate and B12 deficiency induced anemia so cells can still divide with less hemoglobin |
|
|
Term
|
Definition
| chronic relatively mild protein energy deficiency |
|
|
Term
| Wasting, two types and what the main difference between them |
|
Definition
- acute protein energy malnutrition, more severe
- Marasmus - marked loss of subcutaneous fat and skeletal msucle (low weight for height)
- Kwashiorkor: wastin with edema and impaired renal function
|
|
|
Term
Two essential fatty acids
what are the symtpoms of deficiency? |
|
Definition
linoleic (18:2, n-6,9)
(all cis)
linoleic acid (18:3, n-,3,6,9)
(all cis)
Deficiency:reduced growth rates, scaly dermatitis with increased loss of water, male and female infertility, depressed inflammatory responses, kidney abnormalities, abnormal liver mitochondira. |
|
|
Term
Dietary fiber
Is it an energy source?
Which is implicated in decreasing cholesterol?
What are the three mechanims by which this is possible? |
|
Definition
- no
- soluble, as opposed to insoluble
1) act as bile acid sequestering agent
2) reduce rate of insulin rise by slowing CHO absorption thereby slowing cholesterol synthesis
3) stimulate production of short chain fatty acids which are absorbed by portal circulation and inhibit cholesterol synthesis |
|
|
Term
Vitamin A
Functions:
Deficiency symptoms:
Toxicity symptoms: |
|
Definition
Functions: retinoic acid is essential for cellular growth and differentiation
Required for vision
Deficiency symptoms: Night blindness, stages of xerophthalmia immune dysfunction and poor growth
Toxicity: Nausea, vomiting, bright red gingiva |
|
|
Term
Mechanism for Vitamin A in
1) vision
2) cellular proliferation/differentiation |
|
Definition
1) 11-cis-reintal binds with opsin in rods or related proteins in cones of retina
- photoexcited rhodopsin activates G-protein that leads to closing of iron channel and hyperpolarization of rod membrane -> initiation of nerve impulses
2) Retinoic acid binds retinoic acid receptor which allows transcription of retinoic acid response element. In it's absence, this gene is not transcribed. |
|
|
Term
|
Definition
-UV causes cholesterol conversion to vitamin D3
-Vitamin D3 binds D3 binding protein, which is taken up by the liver and converted to 25-hydroxy D3
-25-OH D3 is taken up by kidney where alpha-1hydroxylase converts it to it's active form:
1,25-(OH2) D3 |
|
|
Term
What is the active form of Vitamin D?
What is the primary circulating form? |
|
Definition
active form: 1,25-(OH2) D3
Main circulating form: 25-(OH) D3 |
|
|
Term
Vitamin D fucntions
Vitamin D deficiency symptoms
|
|
Definition
- maintain serum calcium and phosphus concentrations
increase calbindin and Ca2+ transporters
- deficiency symptoms: rickets in children (bone pain, muscle weakness, opacity of bone) and osteomalacia in adults |
|
|
Term
| Three mechanisms of Vitamin D deficiency? |
|
Definition
1) endogenous
2) dietary intake
3) increase bone Ca2+ deposition |
|
|
Term
|
Definition
| antioxidant regulated by liver, potent peroxyl radical scavenger, protects PUFA in phospholipids of cell membranes |
|
|
Term
|
Definition
| cofactor for membrane bound carboxylase system involved in poststranslationalcarboxylation of non-coagulation-related proteins, including bone associated proteins, osteocalcin and matrix Gla protein. |
|
|
Term
Niacin function
Deficiency symptoms |
|
Definition
- coenzymes for redox reactions, ATP synthesis and ADP ribose transfer reactions
- dietary tryptophan metabolized to NAD
-Pellegra:
Diarrhea, Dermatitis, Dermatosis, Death |
|
|
Term
|
Definition
| - autosomal recessive disorder characterized by impaired synthesis of niacin from tyrptophan resulting in pellagra like symptoms |
|
|
Term
| four folate associated enzymes |
|
Definition
1) Thymidine synthetase
2) Methionine synthase (homocystein methyltransferase)
3) Methyline THF reductase
4) dihydrofolate reductase |
|
|
Term
|
Definition
megaloblastic anemia - large, undividing red blood cells
weakness, dyspnea, sore tongue, irritability, forgetfulness, anorexia, headach, concurrent B12 deficiency |
|
|
Term
B12 deficiency
What enzyme inhibition causes the methyltrap, leading to an elevation of what? |
|
Definition
- Main sx: pernicious anemia - neuropathy
- methionine synthase leading to impaired DNA synthesis and megaloblasitc anemia
- methyl-THF |
|
|
Term
| what is elevated in the urine due to B12 deficiency? |
|
Definition
|
|
