560D Flashcards
3 factors that can increase the likelihood of getting Iron Deficiency Anemia:
- Heavy menstruation
- Copper deficiency
- Celiac disease
Anemia of chronic disease can be caused from prolonged inflammation (IL-6, Cytokines, infection), which increases _____________ to sequester iron in tissues so germs can’t use the iron to reproduce.
Hepcidin (synthesized by the liver and controls iron homeostasis)
What are the four conditionally essential amino acids?
Arg, Gln, Gly, Tau
Mutations in the SN1-SN2 transporter can lead to elevations in what 3 AA?
Gln, Asn, His
The central energy pathways begin with digestion and assimilation of fats, carbohydrates, and proteins. Long-chain FA require the use of the _________________ shuttle to help them enter the mitochondrial for beta-oxidation.
Carnitine
Inhibition of CoQ10 synthesis from statin drugs, will typically reveal elevations in urinary ________________.
Hydroxymethylglutarate
When considering toxic exposures, through what barriers and routes of entry can lipophilic (fat loving) toxins be absorbed?
- GI tract
- Skin
- Lymphatics
- In Utero
Fat toxins enter thru GI SKIN LYMPH UTERO
One of the phthalate esters used in plastic wrap to cover foods can lead to decreased kidney function, increased cysts, increased peroxisome proliferation and even liver cancer in rats. This is a concern to humans because ________________ is used in plastic tubing for hemodialysis.
Di(2-ethylhexyl) phthalate (DEHP)
A client with diagnosed IDA comes to you because he eats meat-based protein and green leafy vegetables but his iron levels have not increased. What other nutrient is needed to properly absorb iron?
Vitamin C
It is important to differentiate IDA from Thalassemia because…
Blood transfusion in Thalassemia can lead to iron overload
Sideroblastic anemia is an X-linked condition where the enzyme called __________ is mutated, leading to excess iron in the RBC mitochondria.
Delta-aminolevulinic acid synthase (this is also the enzyme that controls the rate-limiting step in heme synthesis)
Glucose-6-Phosphate dehydrogenase is the enzyme that reduces (1) to (2) as part of the hexose monophosphate shunt pathway (pentose phosphate pathway). G6PD deficiency can lead to RBC hemolysis from oxidant stress because (2) is no longer available to help recycle glutathione.
- NADP+
2. NADPH
What symptoms of Iron Deficiency Anemia block hepcidin expression, leading to increased ferroportin and iron availability?
Hypoxia and Erythropoiesis
Methemoglobin differs from hemoglobin by its inability to bind to oxygen because:
The iron has been oxidized to Fe3+
It is important to simultaneously check vitamin B12 and folate levels because administration of folic acid can mask vitamin B12 deficiency, leading to neurological demyelination that is often irreparable. The 2 constituents that accumulate in B12 deficiency, one of which competitively inhibits FA biosynthesis leading to increased myelin sheath turnover/degradation are:
Methylmalonyl CoA and Homocysteine
A client with diagnosed pernicious anemia does not have the ability to produce intrinsic factor. What nutrient binds to intrinsic factor to be properly absorbed and where is it absorbed in the GI tract?
B12 binds to IF and is absorbed in the ileum
GI conjugase enzymes hydrolyze folate to the monoglutamate form. What cofactor is needed for this reaction?
Zinc
Vitamin B12 is composed of ___________________, which can have hydroxy-, methyl-, or deoxyadenosyl- groups attached to it.
Corrin ring with cobalt
The reabsorption of urobilinogens from the GI to the liver so they can be resecreted into the bile is called
the _________________.
Enterohepatic Urobilinogen cycle
How can porphyrias arise from a low caloric (low glucose) diet?
Because ALA synthase 1 will be upregulated to push heme biosynthesis (Glucose inhibits ALAS1, so it is automatically upregulated in the absence of glucose. This is why glucose is given IV to people with acute porphyrias and why it is important for people with porphyrias to avoid crash dieting and low-carb diets).
Obstruction of the bile duct from gallstones (called extrahepatic cholestasis) can cause symptoms of pale clay-colored stools and dark urine upon standing. This occurs because:
The liver regurgitates conjugated bilirubin into the blood and the decline of conjugated bilirubin entering the GI tract
Hyperbilirubinemia can lead to Jaundice, yellowing of the skin, nail beds and whites of the eyes. Acute hemolytic crises found in G6PD deficiency and Sickle Cell Anemia can cause hyperbilirubinemia and jaundice from an:
Increase in unconjugated and conjugated bilirubin
Which enzyme in the heme biosynthesis pathways contains zinc and is located in the cytosol?
Delta-ALA-Dehydratase (this enzyme converts 2 ALA into porphobilinogen and is very sensitive to heavy metals like lead because they replace the zinc)
How is a porphyrin different from a porphyrinogen?
Porphyrins are oxidized forms of porphyrinogens