Exam 5 Practice Questions

In what form must a drug be in order to elicit a pharmacologic response? A. Free B. Bound to albumin C. Bound to globulins D. Bound to fatty acids

A. Free

A patient's total cholesterol is 300 mg/dL, his HDL cholesterol is 50 mg/dL, and his triglyceride is 200 mg/dL. What is this patient's calculated LDL cholesterol? A. 200 B. 210 C. 290 D. 350

B. 210

Which of the following is a commonly encountered xanthine that could potentially interfere with the determination of theophylline? A. Nicotine B. Caffeine C. Amphetamine D. Procainamide

B. Caffeine

Identification of the urinary metabolite benzoylecgonine would be useful in determining exposure to which of the following drugs? A. Codeine B. Cocaine C. Amphetamine D. Propoxyphene

B. Cocaine

Which of the following drugs is used as an immunosuppressant in organ transplantation, especially in liver transplants? A. Methotrexate B. Amiodarone C. Tacrolimus D. Paroxetine

C. Tacrolimus

What is the approximate number of half-life periods required for a serum drug concentration to reach 97-99% of the steady state? A. 1-3 B. 2-4 C. 5-7 D. 7-9

C. 5-7

Which of the following serum components is able to alter the free drug level in plasma? A. Creatinine B. Urea C. Albumin D. Calcium

C. Albumin

The quantification of the high-density lipoprotein cholesterol level is thought to be significant in the risk assessment of what disease? A. Pancreatitis B. Cirrhosis C. Coronary artery disease D. Hyperlipidemia

C. Coronary artery disease

Enzymatic methods for the determination of total cholesterol in serum utilize a cholesterol oxidase-peroxidase method. In this method, cholesterol oxidase reacts specifically with what? A. Free cholesterol and cholesteryl ester B. Free cholesterol and fatty acid C. Free cholesterol only D. Cholesteryl ester only

C. Free cholesterol only

A mother brings her obese, 4-year-old child who is a known type 1 diabetic to the laboratory for a blood workup. She states that the boy has been fasting for the past 12 hours. After centrifugation the tech notes that the serum looks turbid. The specimen had the following results: blood glucose = 150 mg/dL, total cholesterol = 250 mg/dL, HDL cholesterol = 32 mg/dL, triglyceride = 395 mg/dL. What best explains these findings? The boy A. Is a low risk for coronary artery disease B. Is a good candidate for a 3-hour oral glucose tolerance test C. Has secondary hyperlipidemia due to the diabetes D. Was not fasting when the specimen was drawn

C. Has secondary hyperlipidemia due to the diabetes

Which of the following techniques can be used to quantify apolipoproteins? A. Spectrophotometric endpoint B. Ion-selective electrode C. Immunonephelometric assay D. Refractometry

C. Immunonephelometric assay

Which of the following is an example of an antiarrhythmic drug that has a metabolite with the same action? A. Quinidine B. Digoxin C. Procainamide D. Nortriptyline

C. Procainamide

In regard to drug distribution patterns, which of the following statements is false? A. Drug metabolism is slower in newborns than adults. B. Drug metabolism is more rapid for 6-year-old children than for adults. C. Renal clearance of drugs is faster in newborns than adults. D. Drug metabolism often changes during pubescence.

C. Renal clearance of drugs is faster in newborns than adults.

For what colorimetric determination is the Trinder reaction widely used? A. Acetaminophen B. Propoxyphene C. Salicylate D. Barbiturate

C. Salicylate

Which of the following classes of compounds has a sedative effect and as such is used to treat anxiety? A. Amphetamines B. Opiates C. Cannabinoids D. Benzodiazepines

D. Benzodiazepines

Anticoagulated whole blood is the preferred specimen in determining exposure to what compound? A. Methanol B. Mercury C. Acetaminophen D. Carbon monoxide

D. Carbon monoxide

Which of the following is an example of a phenothiazine drug? A. Cyclosporine B. Theophylline C. Phenytoin D. Chlorpromazine

D. Chlorpromazine

To detect barbiturate abuse when analyzing urine specimens, immunoassay is the method of choice for screening. The method of choice for confirmation is:

GC/MS

Currently the MOST common method for the confirmation of serum barbiturates is:

Gas-liquid chromatography, mass spectrometry

high levels of which lipoprotein class are associated with decreased risk of atherosclerosis?

HDL

Which of the following statements is correct? * there are several subfractions of...

HDL and LDL.

Which lipid abnormality is most closely linked to heart disease?

Hypercholesterolemia

In familial β dyslipoproteinemia (formerly type III hyperlipoproteinemia), which lipoprotein accumulates?

IDL

A drug that is administered through which of the following routes will reach peak level the quickest?

IV

To produce reliable results, when should blood specimens for lipid studies be drawn?

In the fasting state, about 9-12 hours after eating

A 46-year old known alcoholic with liver damage is brought in the ER unconscious. One would expect his lipid values to be affected in what way?

Increased

When a patient is suspected of intoxication, what would you expect the osmol gap to be?

Increased

Lipoprotein (a), or Lp(a), is significant when elevated in serum because it:

Is an independent risk factor for atherosclerosis

Albuterol is a fast-acting bronchodilator used acutely during asthma attacks. All of the reasons below explain why therapeutic drug monitoring (TDM) for albuterol is not available or common, EXCEPT?

It has a very narrow therapeutic window

Treatment recommendations for patients with coronary heart disease are based upon measurement of which analyte?

LDL cholesterol

How is valproic acid (Depakote) administered?

oral preparation

The study of drug disposition in the body - how and when drugs enter the circulation, how long they stay there, and how they are eliminated is called?

pharmacokinetics

Of the following anticonvulsant medications, which one does not rely soley on the liver to metabolize it for excretion?

phenobarbital - mostly metabolized by hepatocytes, but has significant filtration by the kidney

an antiepileptic (or anticonvulsant) used to control seizure disorders is:

phenytoin.

Which enzyme deficiency is most commonly associated with familial hypertriglyceridemia associated with fasting plasma chylomicrons (formerly type I hyperlipoproteinemia)?

post-heparin-activated lipoprotein lipase deficiency

Which of the folloing is the prodrug of phenobarbital?

primidone

phenobarbital is a metabolite of:

primidone

Which one of the following statements about lead poisoning is false?

serum lead level is a good inexpensive screening test for lead toxicity. - whole blood is the best for lead toxicity (serum levels fluctuate and do not remain positive for long)

Which of the following reagents is used in the direct HDL cholesterol method?

sulfated cyclodextrin

Which of the following is a bronchodilator used to treat a 39-year-old male asthmatic patient?

theophylline

a drug that relaxes the smooth muscles of the bronchial passages is:

theophylline

a high volume of distribution means that:

there is a greater amount of tissue distribution by the drug.

A person has a fasting triglyceride level of 240 mg/dL. The physician wishes to know the patient's non-HDL cholesterol level. What cholesterol fractions should be measured?

total cholesterol and HDL cholesterol

An EDTA blood sample is collected from a nonfasting person for a CBC. The physician collected the sample from the femoral vein because venipuncture from the arm was unsuccessful. He called the lab 15 minutes after the sample arrived and requested a lipid study including triglyceride, total cholesterol, HDL cholesterol, and LDL cholesterol. Which test results should be used to evaluate the patient's risk for coronary artery disease?

total cholesterol and HDL cholesterol (these are least affected by a recent meal)

Which of the following methods for HDL cholesterol is the reference method?

ultracentrifugation

a lipemic serum is separated and frozen at -20C for assay at a later date. one week later, prior to performing an assay for triglycerides, the specimen should be:

warmed to 37C and mixed thoroughly.

the term pharmacokinetics best describes:

what the body does to the drug.

What type of specimen is used for testing cyclosporine levels?

whole blood

testing for the diagnosis of lead poisoning should include:

whole blood lead.

Which type of lipoprotein transports the MAJORITY of cholesterol to cells for steroid hormone synthesis or cell membrane incorporation?

LDL

which lipoprotein carries ~70% of plasma cholesterol?

LDL

famililal hypercholesterolemia shows elevated:

LDL (defect in LDL receptors).

What is the correct calculation using the Friedewald calculation for LDL?

LDL = total cholesterol - HDL - triglycerides/5 VALID ONLY IF triglycerides are <400 mg/dL.

Which one of the following adipocyte products is an important messenger in metabolism, signaling the hypothalamus that there are changes in fat stores? - Leptin - Resistin - IL-6 - Angiotensin

Leptin Leptin signals the hypothalamus that there are changes in fat stores. Leptin is synthesized and released from adipose cells in response to adipose tissue changes. It reduces intracellular lipid levels in many types of body cells and thus improves insulin sensitivity. It is an appetite suppressant and inhibitor of fatty liver formation.

Which statement best describes small dense LDL particles that can occur in atherogenic dyslipidemia?

Small dense LDL molecules are more atherogenic because they can more easily move into the endothelium and vessel wall

which disease results from a familial absence of high density lipoprotein?

Tangier disease

a 9 month old boy from israel has gradually lost the ability to sit up right, and develops seizures. he has an increased amount of a phospholipid called GM2-ganglioside in his neurons, and he lacks the enzyme hexosaminidase A in his leukocytes. these findings suggest:

Tay-sachs disease.

When collecting a urine specimen for workplace drug testing, which of the following situations may indicate that the specimen has been tampered with or adulterated?

the specific gravity is 1.001.

what drug is used to treat asthma and COPD in patients with nocturnal symptoms or problems with inhalers?

theophylline

The range between a drug's effective dose and its toxic dose is called?

therapeutic window

blood specimens for digoxin assays should be obtained between 8 hours or more after drug administration because:

tissue and serum levels need to reach equilibrium.

If the LDL cholesterol is to be calculated by the Friedwald formula, what are the 2 measurements that need to be carried out by the same procedure?

total cholesterol and HDL cholesterol

Lipemia in a fasting serum sample is most likely caused by an increase in serum levels of:

triglycerides

which lipid results would be expected to be falsely elevated on a serum specimen from a non-fasting patient?

triglycerides

blood was collected in a serum separator tube on a patient who has been fasting since midnight. the time of collection was 7 am. the lab test which should be recollected is:

triglycerides.

chylomicrons are mainly composed of:

triglycerides.

Which of the following is true of genotype screening in pharmacogenomics? -Genotype screening gives a better overall picture of drug metabolism than measuring metabolism with probe drugs. -Genotyping does not take into account drug interactions which can affect metabolism. -Genotyping typically involves measuring only one mutation site or polymorphism. -Genotyping has no known impact on drug metabolism.

-Genotyping does not take into account drug interactions which can affect metabolism.

Nortriptyline is the active metabolite of which of the following drugs? A. Amitriptyline B. Desipramine C. Imipramine D. Doxepin

A. Amitriptyline

Toxic levels of lithium can cause lethargy, apathy, muscle weakness up to and including seizures and coma. What is the toxic level of lithium?

1.5-2 mmol/L

What is the half-life of immunosuppressive drugs cyclosporine and tacrolimus?

10-12 hours

What is the half-life for aminoglycoside antibiotics in the blood?

2-3 hours

a drug has a half life of 6 hours. if a dose is given every 6 hours, a steady state drug level would usually be achieved in:

24-42 hours.

what is the half life of digoxin in plasma?

38 hours

Select the reagent needed in the coupling enzyme reaction used to generate a colored product in the cholesterol oxidase method for cholesterol.

4-aminoantipyrine

chemical composition of HDL cholesterol

5% trigs 15% cholesterol 50% protein

If a drug is given at intervals that are the same as its half-life, approximately how long will it take the drug to reach steady state?

5-7 half lives

the protein composition of HDL is what percentage by weight?

50%

When should a peak digoxin level be drawn?

8-10 hours after an oral dose (has a slow uptake into the tissues)

What is the HDL cholesterol cutpoint recommend by NCEP?

<40 mg/dL

Which of the following statements is true regarding cardiovascular disease and adipose tissue? -Obesity in metabolic syndrome contributes to the development of cardiovascular disease by increased synthesis and secretion of adiponectin -Increased synthesis and secretion of PAI-1 in metabolic syndrome contributes to cardiovascular disease by increasing blood pressure -A state of abnormal lipids and lipid levels found in metabolic syndrome contribute to the development of cardiovascular disease

A state of abnormal lipids and lipid levels found in metabolic syndrome contribute to the development of cardiovascular disease

Which of the following results would be the most consistent with high risk for coronary heart disease? A. 20 mg/dL HDL cholesterol and 250 mg/dL total cholesterol B. 45 mg/dL HDL cholesterol and 210 mg/dL total cholesterol C. 50 mg/dL HDL cholesterol and 180 mg/dL total cholesterol D. 55 mg/dL HDL cholesterol and 170 mg/dL total cholesterol

A. 20 mg/dL HDL cholesterol and 250 mg/dL total cholesterol

Which of the following may be described as a variant form of LDL, associated with increased risk of atherosclerotic cardiovascular disease? A. Lp(a) B. HDL C. ApoA-I D. ApoA-II

A. Lp(a)

Which of the following is an example of a long-acting barbiturate? A. Phenobarbital B. Amobarbital C. Secobarbital D. Pentobarbital

A. Phenobarbital

What is the recommended name for diphenylhydantoin? A. Phenytoin B. Nalorphine C. Primidone D. Carbamazepine

A. Phenytoin

Which of the following tests would be particularly useful in determining isopropanol exposure? A. Serum osmolality and urine acetone B. Urine osmolality and serum osmolality C. Urine acetone and urine osmolality D. Serum sodium and serum acetone

A. Serum osmolality and urine acetone

Which of the following drugs is used as a bronchodilator? A. Theophylline B. Phenytoin C. Amikacin D. Clozapine

A. Theophylline

Which of the following lipid tests is least affected by the fasting status of the patient? A. Cholesterol B. Triglyceride C. Fatty acid D. Lipoprotein

A. cholesterol

A 46-year-old known alcoholic with liver damage is brought into the emergency department unconscious. In what way would you expect his plasma lipid values to be affected? A. Increased total cholesterol, triglyceride, LDL, and VLDL B. Increased total cholesterol and triglyceride, decreased LDL and VLDL C. Decreased total cholesterol, triglyceride, LDL, and VLDL D. Normal lipid metabolism, unaffected by the alcoholism

A. increased total cholesterol, triglyceride, LDL, and VLDL

A physician needs to prescribe a drug to a patient but the drug has a narrow therapeutic window. He is concerned about possible toxic effects. To assess the upper concentration of such a drug, which time for drawing the specimen do you think makes the most sense?

About 1 hour after an oral dose

Which of the following medications is known to cause Reye's Syndrome in children?

Acetylsalicylic acid (aspirin)

What do "direct" or homogenous methods for LDL cholesterol assay have in common?

All use a detergent to facilitate selective reactivity with reagent enzymes

Which of the following is a true statement about aminoglycoside antibiotics? -Aminoglycosides have a half-life of 1-2 hours and are metabolized by the liver. -Aminoglycosides are antibiotics used to treat only Gram-negative bacterial infections. -Aminoglycosides are antibiotics used to treat only Gram-positive bacterial infections. -Aminoglycosides can be toxic antibiotics that are used to treat bacterial infections when such bacteria are resistant to less-toxic antibiotics.

Aminoglycosides can be toxic antibiotics that are used to treat bacterial infections when such bacteria are resistant to less-toxic antibiotics.

Which medication would be prescribed for narcolepsy?

Amphetamine

Which of the following apolipoproteins contributes the greatest mass to the structure of high-density lipoprotein (HDL)? - Apo A - Apo B - Apo C - Apo G

Apo A Apo G des not exist

Which of the following mechanisms accounts for the elevated plasma level of β lipoproteins seen in familial hypercholesterolemia (formerly type II hyperlipoproteinemia)?

ApoB-100 receptor defect

What is the sedimentation nomenclature associated with alpha-lipoprotein? A. Very-low-density lipoproteins (VLDLs) B. High-density lipoproteins (HDLs) C. Low-density lipoproteins (LDLs) D. Chylomicrons

B. HDLs

An epileptic patient receiving phenytoin develops acute glomerulonephritis. What change, if any, would be expected in the patient's circulating drug level? A. Decrease in free drug B. Increase in free drug C. Increase in protein-bound drug D. No change in circulating drug level

B. Increase in free drug

Increased trough levels of aminoglycosides in the serum are often associated with toxic effects to which organ? A. Heart B. Kidney C. Pancreas D. Liver

B. Kidney

Which of the following is used in the treatment of manic depression? A. Potassium B. Lithium C. Calcium D. Chloride

B. Lithium

After absorption, codeine is rapidly metabolized to what compound? A. Phencyclidine B. Morphine C. Methadone D. Propoxyphene

B. Morphine

Heroin is synthesized from what drug? A. Diazepam B. Morphine C. Ecgonine D. Chlorpromazine

B. Morphine

What is the principle of the "direct" or "homogeneous" HDL cholesterol automated method, which requires no intervention by the laboratorian? The direct HDL method A. Quantifies only the cholesterol in HDL, whereas the precipitation HDL method quantifies the entire lipoprotein B. Utilizes polymers and detergents that make the HDL cholesterol soluble while keeping the other lipoproteins insoluble C. Uses a nonenzymatic method to measure cholesterol, whereas the other methods use enzymes to measure cholesterol D. Uses a column chromatography step to separate HDL from the other lipoproteins, whereas the other methods use a precipitation step

B. Utilizes polymers and detergents that make the HDL cholesterol soluble while keeping the other lipoproteins insoluble

Each lipoprotein fraction is composed of varying amounts of lipid and protein components. The beta-lipoprotein fraction consists primarily of which lipid? A. Fatty acid B. Cholesterol C. Phospholipid D. Triglyceride

B. cholesterol

What substance is the precursor to all steroid hormones? A. Fatty acid B. Cholesterol C. Triglyceride D. Phospholipid

B. cholesterol

Free drug levels can generally be determined by analyzing what body fluid? A. Whole blood B. Ultrafiltrate of plasma C. Urine D. Protein-free filtrate of plasma

B. ultrafiltrate of plasma

Cyclosporine and tacrolimus (both immunosuppressive drugs) have multiple therapeutic ranges, why?

Because both drugs have ranges dependent on the organ transplanted and the time after transplantation.

The term "lipid storage diseases" is used to denote a group of lipid disorders, the majority of which are inherited as autosomal recessive mutations. What is the cause of these diseases? A. Excessive dietary fat ingestion B. Excessive synthesis of chylomicrons C. A specific enzyme deficiency or nonfunctional enzyme form D. An inability of adipose tissue to store lipid materials

C. a specific enzyme deficiency or nonfunctional enzyme form

The turbid, or milky, appearance of serum after fat ingestion is termed postprandial lipemia, which is caused by the presence of what substance? A. Bilirubin B. Cholesterol C. Chylomicron D. Phospholipid

C. chylomicron

Exogenous triglycerides are transported in the plasma in what form? A. Phospholipids B. Cholesteryl esters C. Chylomicrons D. Free fatty acids

C. chylomicrons

Cholesterol ester is formed through the esterification of the alcohol cholesterol with what substance? A. Protein B. Triglyceride C. Fatty acid D. Digitonin

C. fatty acid

Name a commonly used precipitating reagent to separate HDL cholesterol from other lipoprotein cholesterol fractions. A. Zinc sulfate B. Trichloroacetic acid C. Heparin-manganese D. Isopropanol

C. heparin manganese

The VLDL fraction primarily transports what substance? A. Cholesterol B. Chylomicron C. Triglyceride D. Phospholipid

C. triglyceride

Which method is considered the candidate reference method for triglyceride measurement?

CDC modification of van Handel and Zilversmit

All of the following are therapeutic drugs used to treat cardiac disease, EXCEPT? -Carbamazepine -Digoxin -Procainamide -Quinidine

Carbamazepine

Tricyclic Antidepressants (TCAs) are used to treat insomnia, depression, extreme apathy, and loss of libido. All of the following are TCAs, EXCEPT? -Imipramine -Doxepin -Clozapine -Amitriptyline

Clozapine

What is the purpose of the saponification step used in the Abell-Kendall method for cholesterol measurement?

Convert cholesterol esters to free cholesterol

Acetaminophen is particularly toxic to what organ? A. Heart B. Kidney C. Spleen D. Liver

D. Liver

What is the active metabolite of the antiarrhythmic drug procainamide? A. Pronestyl B. Disopyramide C. PEMA D. NAPA

D. NAPA

Which of the following tests would most likely be included in a routine lipid profile? A. Total cholesterol, triglyceride, fatty acid, chylomicron B. Total cholesterol, triglyceride, HDL cholesterol, phospholipid C. Triglyceride, HDL cholesterol, LDL cholesterol, chylomicron D. Total cholesterol, triglyceride, HDL cholesterol, LDL cholesterol

D. Total cholesterol, triglyceride, HDL cholesterol, LDL cholesterol

A healthy, active 10-year-old boy with no prior history of illness comes to the lab after school for a routine chemistry screen in order to meet requirements for summer camp. After centrifugation, the serum looks cloudy. The specimen had the following results: blood glucose = 135 mg/dL, total cholesterol =195 mg/dL, triglyceride =185 mg/dL. What would be the most probable explanation for these findings? The boy A. Is at risk for coronary artery disease B. Has type 1 diabetes mellitus that is undiagnosed C. Has an inherited genetic disease causing a lipid imbalance D. Was most likely not fasting when the specimen was drawn

D. Was most likely not fasting when the specimen was drawn

The kinetic methods for quantifying serum triglyceride employ enzymatic hydrolysis. The hydrolysis of triglyceride may be accomplished by what enzyme? A. Amylase B. Leucine aminopeptidase C. Lactate dehydrogenase D. Lipase

D. lipase

Which of the following is most associated with the membrane structure of nerve tissue? A. Cholesterol B. Triglyceride C. Phospholipids D. Sphingolipids

D. sphingolipids

A patient's total cholesterol/HDL cholesterol ratio is 10.0. What level of risk for coronary heart disease does this result indicate? A. No risk B. Half average risk C. Average risk D. Twice average risk

D. twice average risk

Ninety-nine percent of lead absorbed in the body is taken up by what after absorption?

Erythrocytes

All of the following statements are true regarding the hepatic system and drug metabolism, EXCEPT? -Changes in hepatic status will affect the concentration of circulating drugs eliminated. -Hepatic disease states characterized by a loss of functional tissue may result in slower rates of clearance. -Hepatic disease states characterized by a loss of functional tissue may result in a longer drug half-life. -Metabolism of acetaminophen by the MFO system is altered by alcohol and makes it less toxic.

Metabolism of acetaminophen by the MFO system is altered by alcohol and makes it less toxic.

When testing for ethanol, what is actually measured in the enzymatic reaction, that is proportional to ethanol concentration?

NADH

The pharmacogenetic profiling reveals a mutation in a CYP450 enzyme that causes increased enzyme activity. Which of the statements below is incorrect?

The CYP450 variants have no influence on drug metabolism.

SITUATION: A lipemic specimen collected from an adult after a 12-hour fast was assayed for total cholesterol, triglycerides, and HDL cholesterol using a direct HDL method. Following are the results: Total cholesterol = 220 mg/dL HDL cholesterol = 40 mg/dL Triglyceride = 420 mg/dL The physician requests an LDL cholesterol assay after receiving the results. How should the LDL cholesterol be determined?

Perform a direct LDL cholesterol assay. An accurate LDL cholesterol can be reported, if the direct (detergent) method for LDL cholesterol is employed. These methods are not subject to interference by triglycerides at a concentration below 700 mg/dL.

The study of how variations in the human genome affect a given individual's response to medications is called?

Pharmacogenetics

Of the following, which has the longest half-life? -Carbamazepine -Valproic acid -Phenytoin -Phenobarbital

Phenobarbital (half life 70-100 hours)

Which of the following drugs is listed as an anti-convulsants?

Tacrolimus

If a disease or disorder causes serum binding proteins (such as albumin) to decrease, what may occur if the dose of a highly protein-bound drug with a narrow therapeutic window is not adjusted?

The patient may experience toxic effects (high free drug fraction).

Which of the following lipid results would be expected to be FALSELY elevated on a serum specimen from a non-fasting patient?

Triglycerides

Regarding therapeutic drug monitoring, which of the following statements is correct when collecting a specimen for a trough level?

Trough level is tested on a blood sample that is collected immediately prior to when the next dose of the drug is given.

(T/F) drugs that are highly protein bound are good candidates for TDM, since changes in plasma binding proteins can affect drug levels.

True

An obese adult with premature arteriosclerosis is seen in the clinic. When her serum is tested no chylomicrons are present, LDL levels are normal, and VLDL levels are increased. There is an increase in triglycerides and slight increase in cholesterol. Lipoprotein electrophoresis reveals a heavy pre-beta band. She has no skin rash and uric acid is increased. This patient most likely has what type of hyperlipoproteinemia?

Type IV

Following ultracentrifugation of plasma, which fraction correlates with pre-β lipoprotein?

VLDL

which lipoprotein carries endogenous cholesterol?

VLDL

which lipoprotein carries most of the endogenous triglycerides?

VLDL

Upon development of a thin layer chromatogram for the drug analysis, all drug spots (including the standards) had migrated with the solvent front. The most probable cause for this would be:

incorrect aqueous to nonaqueous solvent mixture

How does Aspirin (salicylic acid) affect platelet function?

inhibiting cyclooxygenase

the term steady state refers to:

[drug] in the body is in equilibrium with drug administration and drug elimination.

what type of chemical is lithium?

a cationic metal

In therapeutic drug monitoring, a person who is classified as an ultrarapid metabolizer (UM) would need __________ of a drug metabolized by that enzyme.

a higher dose

a drug's effect is dose dependent until:

a maximum effect is reached. - a plateau is reached due to receptor saturation or transport process overload

which factor is not relevant to TDM of the aminoglycosides, antibiotics and vancomycin?

intestinal absorption

What compound is a crucial intermediary in the metabolism of triglyceride to form energy? -bile -acetyl-coenzyme A - acetoacetate - pyruvate

acetyl coenzyme A

which apoprotein is inversely related to risk of coronary heart disease?

apoprotein A-I

Which of the following is associated with Tangier disease?

apoprotein A-I deficiency

a salicylate level is performed to detect toxicity caused by ingestion of excess:

aspirin.

Which one of the following statements about acetaminophen metabolism is false? It is metabolized in the kidney It is largely metabolized in the liver to glucuronide and sulfonate conjugates A small amount is metabolized via cytochrome oxidase to a reactive benzoquinoneimine intermediate The benzoquinoneimine intermediate becomes toxic to the liver once tissue glutathione becomes depleted

it is metabolized in the kidney - FALSE. * it is metabolized in the liver

Zinc protoporphyrin or free erythrocyte protoporphyrin measurements are useful to assess blood concentration of:

lead.

a 3 year old child was evaluated for abdominal pain and anorexia by a physician. CBC revealed a hemoglobin of 9.8 g/dL and basophilic stippling of the RBCs. the doctor should order further tests to check for poisoning from:

lead.

cocaine is metabolized to:

benzoylecgonine

Atherosclerosis is due to:

buildup of plaque.

Which medication is primarily used in the treatment of bipolar disorder?

lithium

a carbonate salt used to control manic-depressive disorder is:

lithium.

premature atherosclerosis can occur when which becomes elevated?

low density lipoproteins

transport of 60-75% of the plasma cholesterol is performed by:

low density lipoproteins

in familial hypercholesterolemia, the hallmark finding is an elevation of:

low density lipoproteins.

Which lipid does not serve as a source of fuel, but can be converted to steroid hormones?

cholesterol

As part of a hyperlipidemia screening program, the following results were obtained on a 25-year-old woman 6 hours after eating: triglycerides: 260 mg/dL cholesterol: 120 mg/dL What is the interpretation of the results?

cholesterol is normal, but trigs are elevated, which may be attributed to the recent meal

which lipoprotein carries exogenous cholesterol?

chylomicrons

a fasting serum sample from an asymptomatic 43 year old woman is examined visually and chemically with the following results: milky appearance of serum after overnight refrigeration: cream layer over turbid serum trigs: 2000 mg/dL cholesterol: 550 mg/dL this sample contains predominantly:

chylomicrons and VLDL.

turbidity in the serum suggests elevation of:

chylomicrons.

A 1-year old girl with a hyperlipoproteinemia and lipase deficiency has the following lipid profile: Cholesterol 300mg/dL LDL increased HDL decreased triglycerides 200mg/dL chylomicrons present A serum specimen from this patient that was refrigerated overnight would most likely be:

creamy layer over clear serum.

lithium therapy is widely used in the treatment of:

manic-depressive (bipolar) disorder.

Which type of dietary fatty acid is not associated with an increase in serum LDL cholesterol production?

monounsaturated cis fatty acids

reverse phase HPLC is being used in TDM. the term reverse phase implies that the column eluant is:

more polar than the stationary phase.

Free therapeutic drug levels are usually higher when serum protein concentrations are below normal. In Which of the following conditions would this most likely occur?

nephrotic syndrome

Which of the following conditions is most consistently associated with secondary hypercholesterolemia?

hypothyroidism

When should blood samples for trough drug levels be collected?

immediately before the next dose is given

Which of the following is the most common technique that is used by clinical laboratories for therapeutic drug monitoring?

immunoassay

chylomicrons are present in which of the following dyslipidemias?

deficiency in lipoprotein lipase activity

Which of the following drugs is used to treat congestive heart failure?

digoxin

which therapeutic drug increases the force of myocardial muscle contraction?

digoxin

A cardiac glycoside that is used in the treatment of congenital heart failure and arrhythmias by increasing the force and velocity of myocardial contraction is:

digoxin.

The function of the very low density lipoproteins (VLDL) is to transport:

endogenous triglycerides.

the function of the major lipid components of VLDL is to transport:

endogenous triglycerides.

Which of the following is a component of antifreeze that can cause severe renal tubular damage, along with similar effects of alcohol poisoning?

ethylene glycol

which of the following elevates carboxyhemoglobin? - nitrite poisoning - exposure to carbon monoxide - sulfa drug toxicity - sickle cell anemia

exposure to carbon monoxide

what disease is a rare familial dyslipidemia characterized by equally elevated serum cholesterol and trig levels due to accumulated remnant lipoproteins in apolipoprotein E2?

familial dysbetalipoproteinemia

which disease refers to individuals with very significantly elevated LDL?

familial hypercholesterolemia

The lecithin to sphingomyelin ratio (L/S) is used to assess:

fetal lung maturity. An L/S ratio above 2:1 indicates mature lung development, whereas a ratio below 1.5:1 indicates pulmonary immaturity. L/S ratio <2.0 indicates an increased risk of respiratory distress syndrome (RDS) at delivery. L/S ratio <1.5 indicates a very high risk of developing RDS.

Bioavailability of an oral drug refers to the:

fraction of the drug that is absorbed into systemic circulation.

Which of the following enzymes is common to all enzymatic methods for triglyceride measurement?

glycerol kinase - all enzymatic trig methods require lipase to hydrolyze trigs, and glycerol kinase to phosphorylate glycerol

Cholesterol esterase is used in enzymatic assays to:

hydrolyze fatty acids bound to the third carbon atom of cholesterol

Select the order of mobility of lipoproteins electrophoresed on cellulose acetate or agarose at pH 8.6.

- Chylomicrons →β→pre-β→α +

When considering therapeutic drug monitoring (TDM), what is the definition of bioavailability?

the fraction of the administered dose that eventually reaches its site of action

Which of the following factors would least affect an orally-administered drug's absorption and/or distribution in the body?

the position of the patient when the drug is taken

what is the purpose of the saponification step in the Abell-Kendall method for total cholesterol?

- convert cholesterol esters to free cholesterol - removes FFAs from CEs

familial dysbetalipoproteinemia

- increased levels of VLDL remnants and chylomicron remnants - deficiency in apoE

ß-hydroxybutyric acid is formed as the result of an accumulation of which of the following?

Acetyl Co-A Acetyl-CoA plays a major role in the metabolism of carbohydrate, lipid, and protein metabolism. It provides the acetyl group to the Krebs cycle to be oxidized for energy production. During extended starvation periods or when there is a defect in carbohydrate metabolism, such as in diabetes mellitus, the body uses lipids (fatty acids) as the main source of energy production. Prolonged usage of fatty acids for energy production will create an excess of acetyl-Co-A. This excess of acetyl-CoA is diverted to a separate pathway in the mitochondria of liver hepatocytes. Here, acetoacetic acid, ß-hydroxybutyric acid, and acetone are produced from the breakdown of acetyl-CoA. These three compounds are known as ketone bodies.

Which lipid test is LEAST affected by the fasting status of the patient?

Cholesterol. Cholesterol levels do not fluctuate as triglycerides, fatty acids, lipoproteins, and chylomicrons do after an individual eats a meal. This is the reason that patients are told to fast; the laboratory needs a fasting sample to determine a lipid profile or panel which includes the latter four components.

Which lipoprotein will form a creamy layer at the top of stored, non-fasting plasma specimens?

Chylomicrons

Which type of lipoprotein is the least dense?

Chylomicrons

What is the major active metabolite of the anticonvulsant drug primidone? A. Phenytoin B. Acetazolamide C. NAPA D. Phenobarbital

D. Phenobarbital

Which of the following statements is true regarding cardiovascular disease and adipose tissue? -Inflammatory cytokines, synthesized and released by adipose tissue, contribute to the development of cardiovascular disease. -Increased synthesis and secretion of PAI-1 in metabolic syndrome contributes to cardiovascular disease by increasing blood pressure. -Obesity in metabolic syndrome contributes to the development of cardiovascular disease by increased synthesis and secretion of adiponectin. -There is no correlation between the amount of adipose tissue and cardiovascular disease.

Inflammatory cytokines, synthesized and released by adipose tissue, contribute to the development of cardiovascular disease.

the drug procainamide is prescribed to treat cardiac arrhythmia. what biologically active liver metabolite of procainamide is often measured simultaneously?

N-acetyl procainamide (NAPA)

Which of the following statements regarding peak level in therapeutic drug monitoring is true?

Peak level is assessed by collecting a blood sample after a dose of the drug is given (at a specified time).

Fetal lung maturity can be determined from amniotic fluid because the surfactant is PRIMARILY composed of:

Phosphatidylcholine and other phospholipids

What are apolipoproteins?

Proteins that are on the surface of lipoprotein molecules that bind enzymes or transport specific proteins and direct lipoproteins to their sites of metabolism.

Below are the laboratory results on a 20-year-old overweight male. His waist circumference is 41 inches and blood pressure is 105/70. Fasting Blood Glucose: 130 mg/dL Triglycerides: 190 mg/dL HDL: 50 mg/dL The National Heart, Lung, and Blood Institute (NHLBI) and American Heart Association (AHA) have created a set of parameters to define the presence of metabolic syndrome. Does this patient meet the criteria for metabolic syndrome diagnosis?

Yes

the most consistent analytical error involved in the routine determination of HDL cholesterol is caused by:

a small concentration of apoB- containing lipoproteins after precipitation.

which enzyme is common to all enzymatic methods for triglyceride measurement?

glycerokinase

the substance that is measured to estimate the serum concentration of triglycerides by most methods is:

glycerol.

the reason carbon monoxide is so toxic is because it:

has 200 times the affinity of oxygen for hemoglobin binding sites.

What type of anticoagulant is generally suitable for TDM analysis?

heparin

which method for quantification of HDL is most suited for clinical lab use?

homogenous