Term
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Definition
Vit B 12, and is req for 2 ess rxns:
FA --> succinyl CoA & Homocysteine --> methionine |
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Term
| What can vit B12 deficiency lead to? |
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Definition
| Accumulation of unusual FA in the cell membrane, which may account for neurological defects. |
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Term
| Where has the most mutations within hemoglobin? |
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Definition
| Japan (due to radiation with the bombing) |
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Term
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Definition
-is a prosthetic group and binds O
-ferrous iron chelated in center
-type of porphyrin called: protoporphyrin IX |
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Term
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Definition
-5 membered rings: pyrrole rings
-held together via bridges (all sorts)
-Bridges give stability and color (deox blood bluer etc...) |
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Term
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Definition
| blue discoloration seen as a result of hypoxia (around lips, nails and other membranes) |
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Term
| Iron atom in the heme group... |
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Definition
| optional 6th bond that the oxygen makes to the iron atom and there is an AA (histamine, proximal and distal) who's N atom forms a 5th bond to the iron |
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Term
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Definition
Mjr Adult (HbA) alpha2/beta2: 97%
Minor Adult (HbB) alpha2/delta2: 2-3%
Fetal (HbF) alpha2/gamma2: 2-3 thrimester |
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Term
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Definition
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Term
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Definition
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Term
| P50 of normal hemoglobin is |
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Definition
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Term
| Sigmoidal curve means (with oxyhemoglobin dissociation curve) |
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Definition
| it's cooperative binding, allosteric molecule (hemoglobin) |
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Term
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Definition
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Term
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Definition
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Term
| P75 of normal hemoglobin is |
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Definition
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Term
| 2,3-Bisphosphoglycerate (BPG) |
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Definition
Negative allosteric effector
-Lowers O2 binding affinity
-Enhances unloading in tissues where the Pp is lower (esp the steep part of the curve)
-Present in RBC
- |
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Term
| BPG concentration in RBC------- during hypoxia |
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Definition
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Term
| When binding affinity lowers, and unloading of O2 occurs the curve... |
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Definition
| The curve shifts to the right |
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Term
| When tissues need O2, hemoglobin is in a form where it doesn't hold the O2 as tightly, in order to give it up to those tissues. |
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Definition
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Term
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Definition
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Term
| Free energy needed for 1st molecule of O2 to bind hemoglobin is high and the subsequent binding energies... |
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Definition
| lower b.c of increasing affinity |
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Term
| Binding of CO2 does what to O2 binding? |
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Definition
| Decreases the O2 affinity of hemoglobin, reversible, non-enzymatic |
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Term
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Definition
| physically dissolved in the plasma in the form of bicarbonate, released out of cell in exchange for a chloride ion (chloride shift) |
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Term
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Definition
| competitive antagonism. hemoglobin with CO has a cherry red color |
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Term
| First couple steps of heme synth take place in the |
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Definition
| mitochondria (main org in cell imp with heme synth) |
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Term
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Definition
| succinyl CoA and glycine are condensed into 5-aminoleculic acid which is transported into the cytosol |
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Term
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Definition
| the proportion of blood volume that is occupied by red blood cells |
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Term
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Definition
| too few RBC or a lower than normal RBC mass = diminished O2 carrying capacity |
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Term
| Anemia characterized via... |
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Definition
(1)
1. cell size and shape and heterogeneity
2. cell hemoglobin concentration
3. extent of circulation young RBC
(2)
1. inadequate pardon of RBC
2. increased destruction or loss |
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Term
| What is the pneumonic for DDx? |
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Definition
"Cannt miiss"
C- Congenital
A- Autoimmune/Allergic
N- Neoplastic/Cancer
N- Nutritional
T- Traumatic
M- Metabolic/Endocrine
I-Infectious
I- Iatrogenic (including medications)
S-Social/Substance
S-pSychological |
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Term
| Why is Fe a double edged sword? |
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Definition
-Req for many processes
-toxic in fee form b.c it generates free radicals |
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Term
| Dietary iron: what form does it exist in? |
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Definition
| is steric and must be converted from Fe3+ to Fe2+ so it can be transported across the duodenal enterocyte. Some is retained as ferritin as the major storage form of iron. Once it’s acroos the enterocyte, it is re-oxidized to fe3+ |
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Term
| Most Fe in the body is in |
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Definition
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Term
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Definition
| via regulating how much we store, which is done by hepcidin produced in the liver, it inhibits release of Fe into the bloodstream & NO regulated or efficient mech for excreting Fe from body exists. |
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Term
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Definition
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Term
| HOw do we measure how much Fe is in the body and being transported? |
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Definition
-Serum Fe (circulation bound to transferring)
-TIBC (Total Iron Binding Capacity)
-% Sat
-Serum Ferritin (indirect measure of total body iron stores and not specific - a lot of things can jack up ferritin levels)
- RBC protoporphyrin levels (precursor of heme, accumulates when heme synth is impaired) |
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Term
| In normal physiological states what is our serum Fe? |
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Definition
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Term
| TIBC, what will it do when we have an Fe deficiency? |
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Definition
| elevates b.c it wants to bind more b.c there is a deficiency (via increasing transport capacity) and then serum Fe goes low and the % sat goes low |
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Term
| What are the other 2 things that can cause low serum ferritin? |
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Definition
-severe hypothyroidism
-scurvy (ascorbic acid def) |
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Term
| Ferrous Sulfate-oral prep of choice for Fe def |
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Definition
b.c cheep and effective! can get over the counter for
< 10 dollars/bottle
-prep of choice for replacement therapy |
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Term
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Definition
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Term
| Iron Dextran Injection (iron prep option) |
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Definition
IM, IV
-SE: Nausea and epigastric pain
-Tx for overdose: lavage with PO4 solution, chelating agent: deferoxamine-injection (can be lethal) |
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Term
| Management of Fe deficiency: |
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Definition
-Adequate nutrition
-Iron supplement (oral with Vit C preferred)
-Find and stop bleeding |
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Term
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Definition
| Uneven dist of RNA and Hemoglobin |
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Term
| Marrow response to (case 2) RBC loss |
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Definition
-dramatic capacity to increase RBC pardon: 6-10 x (FINISH)
increase in reticulocytes (young RBC) they are larger than mature, and MCV is generally elevated in hemolytic anemias |
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Term
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Definition
1. Decreased Production
2. Decreased survival: (bleeding, hemolysis [RBC destruction] via mechanical or autoimmune) |
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Term
| How to determine which mech anemia it is? |
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Definition
measure proportion of young RBC (reticulocytes)
high retic: decreased survival (responding appropriately to anemia)
low retic: decreased production |
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Term
| Coombs Test: detecting Ab to RBC |
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Definition
| -directly Ab bound to RBC surface components) or -Indirect (Ab circulating in serum reactive with RBC surface component) |
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Term
Autoimmune hemolysis can be
Warm:
Cold |
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Definition
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Term
| THE 2 kinds of Macrocytic RBC |
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Definition
1. Round macrocytes (usually not due to decreased production, but rather autoimmune)
2. oval macrocytes (WATCH OUT) look for probe with DNA syth in the bone marrow |
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Term
| T/F Neurologic symptoms of B12 def can present in patients with normal MVC and Hemoglobin levels? |
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Definition
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Term
| Major Folate form in plasma (mehtyl-tetrahydrofolate) must be converted into tetrahydrafolate (substrate for 1 C donor) |
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Definition
| THAT is what B12 does (enables body to convert folate into form it needs to use in the 1 C reaction) |
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Term
| Folic Acid Def caused by: |
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Definition
-Inadequate intake: unbalanced diet
-(increased req)...
-Pregnancy, infancy, malignancy, increased heatopoiesis [chronic heolytic anemias], chronic exfoliative skin disorders, hemodialysis |
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Term
| T/F B12 def appears before folate def |
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Definition
FALSE
-folate def tends to appear faster b.c it doesn't stay around as long as B12 (fewer stores) |
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Term
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Definition
-inadequate uptake (vegan)
-Malabsorption
(FNISH) |
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Term
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Definition
-cyanocobalamin injection preferred prep (IM or SC)
-Clincal uses: NON toxic
-Tx of VIT B12 def:
-Megaloblastic anemia |
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Term
| Anemia of chronic disease: |
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Definition
-body Fe stores are normal
-transport of Fe is decreased
-Activated RES shortens RBC half life |
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Term
| The Coombs test can be helpful in the Dx of sickle cell anemia T/F |
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Definition
| FALSE (even though it's a hemolytic anemia) can be used to rule it out b.c it should be (-) |
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Term
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Definition
| from inherited mutations in or near coding region os globin genes |
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Term
| Structural Hemoglobinopathies: |
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Definition
1. alteration in ext hydrophilic AA or contact point AA--> decreased Hgb solubility, decreased RBC deformability (sickle cell)
2. alteration in interior hydrophobic AA
3. (FIISH) |
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Term
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Definition
-GU
-PAIN in hands and feet
-CV-Pulmonary
etc... |
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Term
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Definition
| one copy of normal beta globin gene on chromosome 11 and one copy of abnormal betas (s) gene |
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