Unit 6 Lipids

Card Set Information

Author:
vertopia
ID:
265797
Filename:
Unit 6 Lipids
Updated:
2014-03-18 17:15:01
Tags:
Exam3 Analytical Chemistry
Folders:

Description:
Unit 6 - Lipids
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user vertopia on FreezingBlue Flashcards. What would you like to do?


  1. Identify the major Apoproetein classes:
    • Class A - HDL, Chylomicrons.
    • Class B - VLDL, IDL, LDL
    • Class C - Chylomicrons
    • Class D – unknown function
    • Class E – probably receptor on HDL
    • and LDL.
    • There is also ApoLp(a).
  2. Proper patient preparation, specimen collection, and specimen storage procedures for lipid studies:
    Normal carbohydrate and lipid diet for 2 preceding weeks.  Fast for 12 hours before specimen collection. (...only endogenous lipids)

    Collect in Heparin Plasma for triglyceride assays.  Serum is acceptable but is known to trap a little TG.

    Collect in Na2EDTA plasma for Lipoprotein Electrophoresis.  

    Keep refrigerated and do not freeze.
  3. Normal values for Total Cholesterol for adults and children:
    • Adults
    • Optimal: <200 mg/dL
    • Borderline: 200 – 239 mg/dL
    • High Risk: >240 mg/dL
    •                                             
    • Children
    • Optimal: <170 mg/dL
    • Borderline: 170 – 199 mg/dL
    • High Risk: >200 mg/dL
  4. Normal values for Triglycerides:
    • Optimal: <150 mg/dL
    • Borderline: 150 – 199 mg/dL
    • High Risk: 200 – 499 mg/dL
    • Very High: ≥500 mg/dL
  5. Normal values for HDL cholesterol:
    • Optimal: >60 mg/dL
    • High Risk: <40 mg/dL
  6. Normal value for LDL/HDL cholesterol ratio:
    Average Risk 3.5
  7. Normal value for Total/HDL cholesterol ratio:
    Average Risk 5.0
  8. Normal value for L/S Ratio in amniotic fluid:
    • Mature >2.0 with PG+
    • Borderline 1.6 - 2.0 with PG+
    • Immature <1.6 with PG-
  9. What are the assay methods for Total Cholesterol?
    • Liebermann-Buchard
    • *Reaction of cholesterol as an alcohol with a strong acid under high heat.
    • *Reagents: Acetic Anhydride, Glacial Acetic Acid, strong Sulfuric Acid, and Sodium Sulfate.
    • *Forms: Green Chromagen.

    • Trinder Cholesterol Oxidase Method (similar to Glucose Oxidase)
    • 1. De-esterify cholesterol with Cholesterol Ester Hydrolase.
    • 2. Cholesterol Oxidase is used to form peroxide which is then used to form red chromophore.
    • Interferents at the oxidation step (bilirubin, ascorbic acid, hemoglobin).
  10. What are the assay methods for HDL Cholesterol Fractionation?
    • Precipitation Method: Same as Cholesterol Oxidase method, only LDL and VLDL must be precipitated out using:
    • 1. Heparin and MgCl2
    • 2. Dextrin Sulfate and Ca or Mg salt OR
    • 3. MgCl2 and Phosphotungstic Acid

    • Direct Method:
    • IgG antibodies against LDL, VLDL, and Chylomicrons.  
    • Cholesterol Oxidase will not react with lipoprotein-antibody complexes.
  11. How do you calculate the LDL cholesterol fractionation?
    LDL-C = Total Cholesterol - (HDL-C + TG/5)

    • Assumptions: 
    • Total Cholesterol = VLDL-C + LDL-C + HDL-C
    • VLDL-C = TG/5
  12. What are the assay methods for Serum Triglycerides?
    Glycerol Kinase Method

    • End up with peroxide ⇒ Oxidized (colored) Dye
  13. Name the lipoprotein electrophoresis fractions with their associated classes using both the Fredrickson (electrophoresis) and the Svedberg (density) classifications:
    • Albumin- fastest - no name, FFA
    • Alpha-1 - alpha, HDL, phospholipids
    • Alpha-2 - pre-beta, VLDL, triglycerides
    • Alpha 2/Beta Bridge - floating beta, IDL, cholesterol and triglycerides
    • Beta - beta, LDL, cholesterol
    • Gamma - slowest - no name, Chylomicrons
  14. Describe Type I of the Frederickson Hyperlipoproteinemias including:
    - Serum Appearance
    - Elevated lipoproteins identified during electrophoresis
    - Relative amounts of Triglycerides, Cholesterol, and Chylomicrons.
    • AKA Deficiency in Lipoprotein Lipase Activity
    • Serum: Clear with creamy layer of CM on top.
    • Lipoprotein fraction: CM at point of application.
    • Triglycerides: Elevated but from the CM.
    • Cholesterol: normal to slightly increased.
    • Chylomicrons: Present.  Individual cannot clear this from their blood.
  15. Describe Type II-A of the Frederickson Hyperlipoproteinemias including:
    - Serum Appearance
    - Elevated lipoproteins identified during electrophoresis
    - Relative amounts of Triglycerides, Cholesterol, and Chylomicrons.
    • AKA Familial Hypercholesterolemia - common defect in LDL receptor gene leading to decreased ability to bind LDL and to internalize the LDL into cells.
    • Serum: Clear and unremarkable.
    • Lipoprotein fraction: Elevated Beta LP.
    • Triglycerides: Normal.
    • Cholesterol: Increased LDL with CHOL elevated.
    • Chylomicrons: None in fasting individual.
  16. Describe Type II-B of the Frederickson Hyperlipoproteinemias including:
    - Serum Appearance
    - Elevated lipoproteins identified during electrophoresis
    - Relative amounts of Triglycerides, Cholesterol, and Chylomicrons.
    • AKA Familial Combined Hyperlipidemia - common condition resulting in overproduction of small, dense atherogenic LDL and VLDL with unknown cause.
    • Serum: Clear to faintly turbid due to TG.
    • Lipoprotein fraction: Elevated Beta LP with slight elevation in Pre-Beta LP.
    • Triglycerides and Cholesterol: Elevated.
    • Chylomicrons: None in fasting individual.
  17. Describe Type III of the Frederickson Hyperlipoproteinemias including:
    - Serum Appearance
    - Elevated lipoproteins identified during electrophoresis
    - Relative amounts of Triglycerides, Cholesterol, and Chylomicrons.
    • AKA Dysbetalipoproteinemia - Genetic and rare. Abnormal lipoprotein (IDL).
    • Serum: Slightly turbid.  Possibly creamy CM on top.
    • Lipoprotein fraction: Famous floating Beta band due to production of abnormal lipoprotein IDL (AKA β-VLDL).
    • Triglycerides and Cholesterol: Elevated to about the same degree above the normal range.  Not uncommon for lipids to be 1,000 - 15,000 mg/dL.
    • Chylomicrons: May or may not be present, but patients have a hard time clearing these remnants.
    • It is essential to use Lipoprotein Electrophoresis to detect this HPL.
  18. Describe Type IV of the Frederickson Hyperlipoproteinemias including:
    - Serum Appearance
    - Elevated lipoproteins identified during electrophoresis
    - Relative amounts of Triglycerides, Cholesterol, and Chylomicrons.
    • AKA Hypertriglyceridemia - Most common of them all. Over production of large VLDL with abnormally high TG content while # of particles remains normal.
    • Serum: Turbid.
    • Lipoprotein fraction: Significant increase in Pre-Beta LP.
    • Triglycerides: Elevated.
    • Cholesterol: Normal to slightly elevated.
    • Chylomicrons: None.
  19. Describe Type V of the Frederickson Hyperlipoproteinemias including:
    - Serum Appearance
    - Elevated lipoproteins identified during electrophoresis
    - Relative amounts of Triglycerides, Cholesterol, and Chylomicrons.
    • Combination of Types I and IV - Deficiency of Lipoprotein Lipase and an increased production of VLDL
    • Serum: Turbid with creamy CM layer on top.
    • Lipoprotein fraction: Heavy band of CM at point of application and increase in Pre-Beta LP. (A non-fasting patient could also present this pattern.)
    • Triglycerides: Elevated at a 5:1 ratio above cholesterol.
    • Cholesterol: Elevated.
    • Chylomicrons: Present.
  20. Normal values ofr LDL Cholesterol for adults and children:
    • Adults
    • Optimal <100 mg/dL
    • Above Optimal 100 - 129 mg/dL
    • Borderline 130 - 159 mg/dL
    • High Risk 160 - 189 mg/dL
    • Very High >190 mg/dL

    • Children
    • Optimal <90 mg/dL
    • Above Optimal 90 - 109 mg/dL
    • Borderline 110-129 mg/dL
    • High Risk 130 - 149 mg/dL
    • Very High >150 mg/dL

What would you like to do?

Home > Flashcards > Print Preview