Clin. Chem. Exam 2
Which of the following methods for lipoprotein electrophoresis depends on charge and molecular size? Select one: a. Agarose b. Polyacrylamide gel c. Paper d. Cellulose acetate
B
Enzymatic methods for the determination of total cholesterol in serum utilize a cholesterol esterase and cholesterol oxidase method. In this method, cholesterol oxidase reacts specifically with: Select one: a. Fatty acids and cholesterol esters b. Cholesterol esters only c. Free cholesterol only d. Free cholesterol and cholesterol esters e. Free cholesterol and fatty acids
C
The plasma sample (sitting at 4°-6° C for 24 hours) from a person with hyperchylomicronemia (Fredrickson's type 1 hyperlipidemia) would appear: Select one: a. Cloudy with a creamy layer on top b. Cloudy throughout c. Clear with a creamy layer d. Orange e. Clear and yellow in color
C
What condition is associated with the following densitometry pattern? (GAMMA IS ABSENT IN THIS PATTERN) Select one: a. Monoclonal increase b. Inflammation c. Hypogammaglobulinemia d. Nephrotic syndrome e. Hepatic cirrhosis
C
Which of the following is considered a lipid? Select one: a. Chylomicrons b. Apolipoprotein E c. LDL d. Cholesterol e. HDL
D
A patient with a reduced number of LDL receptors on their hepatic cells will produce excess endogenous cholesterol. Select one: True False
TRUE
Short chain fatty acids pass through the intestine to portal circulation after digestion, due to their small size. Select one: True False
TRUE
Use of plasma in a protein electrophoresis will result in an additional fibrinogen peak. Select one: True False
TRUE
Gout is a pathologic condition characterized by the deposition in joints and other body tissues of: Select one: a. Uric acid b. Phosphorus c. Creatinine d. Urea e. Calcium
A
A patient's plasma is allowed to sit undisturbed at 2° to 6° C for a period of 24 hours. You notice that after the 24 hours that the plasma sample appears turbid throughout. This is most likely due to elevations in which of the following? Select one: a. VLDL b. Chylomicrons c. Total cholesterol d. IDL e. LDL
A
The abnormal metabolism of several of the amino acids has been linked with disorders classified as aminoacidopathies or inborn errors of metabolism. A screening technique used to differentiate between several different amino acids is: Select one: a. Microbiologic analysis b. Chemical analysis c. Chromatography d. Immunoelectrophoresis e. Electrophoresis
A
What is the most appropriate fasting procedure when a lipid study of triglycerides, total cholesterol, HDL, and LDL tests is ordered? Select one: a. 12 hours, nothing but water allowed b. 16 hours, water, smoking, coffee or tea only allowed c. 8 hours, nothing but water allowed d. 12 hours, light meals only e. 10 hours, water, smoking, coffee, tea (no sugar or cream) allowed
A
A commonly used method for the quantitation of serum total protein is the biuret procedure. The intensity of the color produced in the biuret reaction is dependant on: Select one: a. The molecular weight of the protein b. The number of peptide bonds c. Carbonate-free sodium hydroxide d. The acidity of the medium e. The nitrogen content of the protein
B
In a healthy individual the protein fraction with the greatest concentration in serum is: Select one: a. Gamma-globulin b. Albumin c. Alpha-1-globulin d. Alpha-2-globulin e. Beta-globulin
B
Oligoclonal bands are significant in the diagnosis of multiple sclerosis when: Select one: a. They are seen in both the serum and CSF b. They are seen in the CSF and not in the serum c. They are found in urine, serum and CSF d. They appear in both the albumin and globulin fractions of serum and the CSF e. At least five bands are seen in the CSF
B
Select the lipoprotein fraction that carries most of the endogenous triglycerides. Select one: a. Chylomicrons b. VLDL c. HDL d. LDL
B
The broad beta-lipoprotein that occurs in (Type III dislipidemia) familial dysbetalipoproteinemia consists of mainly: Select one: a. Chylomicrons b. IDL c. LDL d. VLDL e. HDL
B
What is the end product of purine catabolism in man? Select one: a. Urea b. Uric acid c. Creatinine d. Allantoin e. Ammonia
B
A copper transport protein that migrates as an alpha-2-globulin is: Select one: a. Transferrin b. Haptoglobin c. Ceruloplasmin d. Erythocuprein e. Fibrinogen
C
A patient presents to his physician for a lipid profile. The following results are received: HDL = 50 mg/dL Total cholesterol = 300 mg/dL Triglycerides = 200 mg/dL The calculated LDL cholesterol is: Select one: a. 290 mg/dL b. 200 mg/dL c. 210 mg/dL d. 350 mg/dL e. 90 mg/dL
C
As part of a lipoprotein phenotyping, it is necessary to perform total cholesterol and triglyceride determinations, as well as lipoprotein electrophoresis. The test results obtained from such studies were • Triglyceride, 340 mg/dL (reference range, <150 mg/dL) • Total cholesterol, 180 mg/dL (reference range, <200 mg/dL) • Pre-beta-lipoprotein fraction increased • Beta-lipoprotein fraction normal • No chylomicrons present • Serum appearance turbid The best explanation for these results would be that the patient exhibits a phenotype indicative of: Select one: a. Type IIb Hyperlipoproteinemia (Familial combined hyperlipidemia) b. Type III Hyperlipoproteinemia (Familail dysbetalipoproteinemia) c. Type IV Hyperlipoproteinemia (Hyperprebetalipoproteinemia or familial hypertriglyceridemia) d. Type V Hyperlipoproteinemia (mixed hyperlipoproteinemia) e. Type I Hyperlipoproteinemia (Familial hyperchylomicronemia)
C
Which of the following apoproteins is responsible for receptor binding for IDL and the chylomicron remnant produced in fat transport? Select one: a. Apo B b. Apo B100 c. Apo E d. Apo A1 e. Apo C
C
Which of the following best describes the order of mobility of lipoproteins electrophoresed on cellulose acetate or agarose at pH 8.6? Select one: a. (-) pre-β, β, α, chylomicrons (+) b. (-) chylomicrons, pre-β, β, α(+) c. (-) chylomicrons, β, pre-β, α (+) d. (-) α, β, pre-β, chylomicrons (+) e. (-) β, pre-β, α, chylomicrons (+)
C
Which of the following lipoproteins is the smallest of all the lipoproteins and is composed of 50% protein? Select one: a. Triglycerides b. Chylomicrons c. HDL d. None of the above e. LDL
C
Which of the following lipoproteins migrates close to the cathode in agarose gel, carries cholesterol to the peripheral tissues, and has an attached Apo-B100? Select one: a. Lp(a) b. Chylomicrons c. LDL d. HDL e. VLDL
C
Which of the following statements regarding serum urea is true? Select one: a. High urea levels can likely cause coma or death b. Levels are independent of diet c. BUN is elevated in prerenal azotemia as well as renal failure d. Build up in the body can lead to a painful condition called gout e. High BUN levels are associated with liver failure or damage
C
Question text Which of the following correctly estimates the VLDL cholesterol in the Friedewald calculation of LDL? Select one: a. Total Cholesterol + HDL b. Total cholesterol ÷ 5 c. Total cholesterol x 0.25 d. Triglycerides ÷ 5 e. Total cholesterol - HDL
D
(SORRY...THIS IS A LONG ONE) A 28-year-old female reports to her physician for a routine examination. She has always been quite healthy, is currently taking no medications, and has a normal blood pressure. Laboratory results are found below: ANALYTE RESULT REFERENCE RANGE Glucose: 95 mg/dL Fasting: <100 mg/dL Total cholesterol 195 mg/dL <200 mg/dL Triglycerides 75 mg/dL <150 mg/dL HDL 48 mg/dL >40 mg/dL LDL 98 mg/dL <100 mg/dL BUN 29 mg/dL 7-20 mg/dL Creatinine 1.0 mg/dL 0.8-1.2 mg/dL BUN/Creatinine 29:1 10:1 to 20:1 Her clinical history and laboratory results most closely indicate which of the following conditions? Select one: a. Diabetes b. Hyperbetalipoproteinemia c. Renal disease d. Prerenal condition e. Hypertriglyceridemia
D
Creatinine, a waste product excreted in the urine, is formed from the catabolism of: Select one: a. Albumin b. Urea c. Glucose d. Creatine e. Lipids
D
Following ultracentrifugation of plasma, which fraction correlates with pre-β lipoprotein? Select one: a. Lpa b. HDL c. LDL d. VLDL e. Chylomicrons
D
In a serum protein electrophoresis, when a barbital buffer of pH 8.6 is employed, the protein fraction that migrates the fastest toward the anode is: Select one: a. Alpha-2-globulin b. Alpha-1-globulin c. Gamma-globulin d. Albumin e. Beta-globulin
D
There are five immunoglobulin classes: IgG, IgA, IgM, IgD & IgE. These immunoglobulins migrate electrophoretically with: Select one: a. Alpha-2-globulins b. Beta-globulins c. Albumin d. Gamma-globulins e. Alpha-1-globulins
D
Which of the following conditions is characterized by a sweet odor on breath, skin and in urine of young infants due to accumulated ketoacids in blood, urine and CSF? It must be detected early to avoid serious brain damage or death and controlled by carefully restricting dietary proteins. Select one: a. Multiple Myeloma b. Cystinuria c. Wilson's disease d. Maple Syrup Urine Disease e. Type I Hyperlipidemia (hyperchylomicronemia)
D
A glycoprotein that binds with hemoglobin to facilitate the removal of hemoglobin by the reticuloendothelial system is: Select one: a. Ceruloplasmin b. C-reactive protein c. Alpha-1-antitrypsin d. Fibrinogen e. Haptoglobin
E
A number of compounds in human serum contain nitrogen. Some of these substances are protein in nature, whereas others are nonprotein-nitrogen compounds. What is the compound that comprises the majority of nonprotein-nitrogen fractions in serum? Select one: a. Creatinine b. Creatine c. Uric acid d. Ammonia e. Urea
E
A precaution that should be exercised in the collection, handling, and use of a specimen for ammonia analysis is: Select one: a. Avoiding a traumatic venipuncture b. Collecting blood in an EDTA or heparin evacuated tube c. Placing the specimen on wet ice immediately d. Avoiding cigarette smoking in the 8 hours prior to collection of the sample e. All of the above
E
A protein that is normally produced by the fetus but found in increased amounts in the amniotic fluid in cases of spina bifida is known as: Select one: a. Alpha-1-antitrypsin b. Hemopexin c. Alpha-2-macroglobulin d. Haptoglobulin e. Alpha-1-fetoprotrein
E
In serum protein electrophoresis, when a buffer solution at pH 8.6 is used, the proteins will: Select one: a. Migrate toward the cathode b. Have a net positive charge c. Be neutrally charged d. Remain stationary e. Have a net negative charge
E
In the enzymatic method of triglyceride measurement, triglycerides are broken down by bacterial lipase into its key components: fatty acids and glycerol, which can then be measured. However, free glycerol in a specimen may cause an erroneous elevation of results of approximately 10 - 20%. How can this error be prevented? Select one: a. None of the above b. Ultrafiltration of the sample to remove excess fats c. Adjusting the pH of the specimen before testing d. This error will not occur if the patient is fasting e. Running a glycerol blank to correct for free glycerol in the sample
E
The red complex developed in the Jaffe method to determine creatinine measurements is a result of the complexing of creatinine with which of the following? Select one: a. Horseradish peroxidase b. Sodium hydroxide c. Sulfuric acid d. Diacetyl monoxide e. Alkaline picrate
E
Which enzyme is used in the detection step for the enzymatic method for both triglyceride and cholesterol measurement? Select one: a. Glycerol phosphate oxidase b. Glycerol phosphate dehydrogenase c. Glycerol kinase d. Pyruvate kinase e. Horseradish peroxidase
E
Which of the following blood samples would serve best to assay lipoproteins because this anticoagulant acts to preserve lipoproteins? Select one: a. Fluoride plasma sample b. Lithium heparin plasma sample c. Sodium heparin plasma sample d. Citrate plasma sample e. EDTA plasma sample
E
A patient with high levels of albumin would be more likely to have edema (water in the tissues) due to increased colloid osmotic pressure. Select one: True False
FALSE
All proteins are made in the liver. Select one: True False
FALSE
The red-orange complex formed by the Jaffe reaction should be read at a wavelength of 340 nm. Select one: True False
FALSE