Enzymes (part two) Flashcards

1
Q

What are the 5 major liver enzymes

A
  1. Aspartate aminotransferase
  2. Alanine aminotrasferase
  3. Alkaline phosphatase
  4. Gamma-glutamyl transerase
  5. Cholinesterase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q
Aspartate Amiontransferase (AST) 
- Three biological sources
A
  1. Heart
  2. Skeletal Muscle
  3. Liver
    (4. Kidney)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q
Aspartate Amiontransferase (AST) 
- typical appearance, peak, and return to normal after myocardial infarction
A

Rises within 12 hours after onset of chest pain; peaks at 18-24 hours; normal within 4-5 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
Aspartate Amiontransferase (AST)
-Two liver diseases that give rise to the greatest elevations
A

Liver (hepatocellular) Disease

  1. Viral Hepatitis
  2. Liver carcinoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
Aspartate Amiontransferase (AST) 
- One muscular disease in which AST is elevated
A
  • Skelatal Muscle Disease (Muscular Dystrophy)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
Aspartate Amiontransferase (AST) 
-If hemolyzed specimens are unacceptable
A

UNACCEPTABLE

-due to high intracellular concentration of AST

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Principle biological source of ALT

A

Liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
alanine aminotransferase (ALT)
-relative use in the diagnosis of liver disease, compared to AST
A

useful in the diagnosis of acute and chronic liver disease; parallels the rise in AST activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
alanine aminotransferase (ALT)
-liver diseases in which it is elevated
A

ALT higher and persists longer than AST in hepatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
alanine aminotransferase (ALT)
-Hemolysis acceptibility?
A

NO HEMOLYSIS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
Alkaline Phosphatase (ALP) 
- four principal biological sources of total ALP
A

liver, bone, intestine, placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
Alkaline Phosphatase (ALP) 
- Hepatobiliary diseases in which ALP is increased
A

biliary obstruction, hepatitis, cirrhosis, infectious mono, and metastic carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
Alkaline Phosphatase (ALP)
- The hepatobiliary disease which gives rise to ALP's highest elevations
A

Biliary Obstruction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
Alkaline Phosphatase (ALP) 
- Bone diseases in which ALP is increased
A

Bone tumors, Paget’s Disease, Rickets, osteomalacia, hyperparathyroidism, and healing fractures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q
Alkaline Phosphatase (ALP)
- Two bone diseases which tie rise to ALP's highest elevations
A

Bone tumors and Paget’s Disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q
Alkaline Phosphatase (ALP) 
- If hemolyzed specimens are unacceptable
A

Gross hemolysis NOT acceptable (slight ok but must be documented)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q
Alkaline Phosphatase (ALP)
- Principle of the Bowers and McComb procedure using p-nitrophenylphosphate
A

reference method; kinetic method that uses pNPP as substrate and measures the rate of p-nitrophenoxide release in AMP buffer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which specific isoenzymes may be distinguished using the heat stability, urea denaturation, amino acid inhibition, and electrophoretic techniques

A

Alkaline Phosphatase (ALP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q
Alkaline Phosphatase (ALP)
- Why the reference range is higher in children than in adults
A

due to rapid bone growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

gamma-glutamyltransferase (GGT)

-two principle biological sources

A

primarily liver, also kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

gamma-glutamyltransferase (GGT)

-degree of elevation used in the differential diagnosis of hepatocellular VS biliary tract disease

A

Elevation up to 5X ULN in biliary tract disorders; lesser elevation (2-5X) in viral hepatitis or active cirrhosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

gamma-glutamyltransferase (GGT)

-clinical usefulness in the diagnosis and monitoring of chronic alcoholism

A

GGT is induced by alcohol and other drugs; used as a marker to check for abstinence from alcohol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

cholinesterase (ChE) in vivo reaction it catalyzes

A

Both enzymes hydrolyze choline esters to form choline and the corresponding fatty acid at the neuromuscular junction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Three clinical applications of measuring ChE activity

A

1 assess exposure to organophospahtes found in insecticides and nerve gas
2 check how patient will react to general anesthesia
3 assess presence of cirrhosis, hepatitis, liver carcinoma (due to decreased production)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Sources of AChE (acetylcholinesterase)

A

Red blood cells and central nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Sources of cholinesterase (ChE)

A

Liver, white matter of brain, serum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q
creatine kinase (CK)
-in vivo reaction it catalyzes
A

Catalysis for ATP formation and phosphorylation of creatine in energy production or usage

28
Q
Creatine Kinase (CK)
-three principle tissue sources
A

skeletal and cardiac muscle, brain

29
Q
Creatine Kinase (CK)
-dimeric composisition and sources of its three isoenzymesm
A

composed of two subunits (M and B); Isoenzymes formed: CK-MM, CK-MB, CK-BB

30
Q
Creatine Kinase (CK)
-typical apprearance, peak, and return to normal after a myocardial infarction
A

Rises 3-8 hours after the onset of chest pain (1st to rise)
Activity peaks at 10-36 hours
Levels return to normal in 3-4 Days

31
Q
Creatine Kinase (CK)
-one muscular disease that gives rise to CK's highest elevations
A

Duchenne’s Muscular Dystrophy (50X ULN)

32
Q
Creatine Kinase (CK)
-cerebral diseases in which CK is elevated
A

Cerebral vascular accident (CVA), stroke, cerebral ischemia

33
Q
Creatine Kinase (CK)
-principle of the Oliver and Rosalki method
A

Analytical procedure for total CK; Increase in absorbance as NADP is oxidized is measured at 340 nm

34
Q

Lipase (LPS)

-principle biological source

A

Pancreas

35
Q

Lipase (LPS)

-two diseases in which LPS is elevated

A

Acute pancreatitis and chronic pancreatitis

36
Q

Lipase (LPS)

-a comparison between the usefulness of LPS and AMS measurements in the diagnosis of pancreatitis

A

levels parallel AMS appearance, but LPS is more specific than AMS

37
Q

Lipase (LPS)

-principles of the turbidimetric/nephelometric procedures

A

Olive oil emulsion is hydrolyzed by LPS, causing a DECREASE in turbidimetry

38
Q

Lipase (LPS)

-principle of coupled enzymatic analytical procedure

A

LPS hydrolyzes fatty acids to form free glycerol which is quantitated colorimetrically

39
Q

Clinical usefulness of performing acid phosphatase (ACP) measurements

A

used to diagnose diseases of the prostate; can also do a prostatic acid phosphatase (PAP) and PSA

40
Q

Glucose-6-phosphate dehydrogenase (G-6-PD)

-biological sources

A

RED BLOOD CELLS, adrenal cortex, lymph nodes, thymus, spleen

41
Q

Glucose-6-phosphate dehydrogenase (G-6-PD)

-disease state associated with LOW levels of G-6-PD

A

hemolytic anemia

42
Q

four major coenzymes used in electron transfer reactions commonly employed in enzyme assays in the lab, including specific wavelength for measurement

A

NAD, NADH, NADP, NADPH; wavelength 340

43
Q

Clinically significant enzymes/lab findings

-myocardial infarction

A

I CK, I CKMB, I AST, I LD

44
Q

Clinically significant enzymes/lab findings

-liver (hepatocellular) disease

A

AST and ALT

45
Q

Clinically significant enzymes/lab findings

-Liver (hepatobiliary) disease

A

ALP and GGT

46
Q

Clinically significant enzymes/lab findings

-bone disease

A

ALP

47
Q

Clinically significant enzymes/lab findings

-brain disease

A

CK-BB, CK

48
Q

Clinically significant enzymes/lab findings

-prostate cancer and hypertrophy

A

ACP

49
Q

Clinically significant enzymes/lab findings

-acute and chronic pancreatitis

A

LPS AMS

50
Q

Clinically significant enzymes/lab findings

-muscle disease and muscular dystrophy

A

CK-MM CK ALS

51
Q
Lactate Dehydronase (LD)
- seven principle biological sources
A

Ubiquitous!

  1. Brain
  2. RBCs
  3. WBCs
  4. Kidney
  5. Liver
  6. Lung
  7. Cardiac
  8. Skeletal muscle
52
Q
Lactate Dehydronase (LD)
-after myocardial infarction
A
  • 10X increase above UNL
  • increase 8-18 hours after onset of chest pain
  • peaks 48-72 hours
  • returns normal 6-10 days
  • ELP shows LD1 > LD 2 or “flipped pattern”
53
Q
Lactate Dehydronase (LD)
-liver disease which it is elevated
A

Hepatobiliary disease

54
Q
Lactate Dehydronase (LD)
- liver disease that gives rise to the greatest elevation
A

Metastatic cancer

55
Q
Lactate Dehydronase (LD)
- two types of anemia where it is elevated
A

Megaloblastic anemia

Pernicious anemia

56
Q
Lactate Dehydronase (LD)
-hemolysis acceptable?
A

Acceptable, but make a comment. Hemolysis increases LD in vivo, and in vitro.

57
Q

Aldolase (ALS)

- three principle biological sources

A
  • skeletal
  • muscle
  • brain
58
Q

Aldolase (ALS)

-one disease state where it is elevated

A

Skeletal muscle diseases, such as muscular dystrophy

59
Q

Amylase (AMS)

- two principle biological sources

A
  1. Pancreas
  2. Salivary glands
  3. Macroamylase
60
Q

Amylase (AMS)

- clinical significance of macroamylase

A

AMS bound to IgG or IgA, causing an increase in total AMS without apparent disease

61
Q

Amylase (AMS)

- clinical significance of measurements in diagnosis of acute pancreatitis, chronic pancreatitis, and mumps

A

???

62
Q

Amylase (AMS)

- what method measures amount of sugars formed from hydrolytic activity of AMS

A

Saccharogenic

63
Q

Amylase (AMS)

- what method uses dye-labeled starch substrates; as AMS hydrolyzes the starch, an increase in color is quantified

A

Chromilytic

64
Q

Amylase (AMS)

-method that measures decrease in starch substrate concentration as AMS works on starch.

A

Amyloclastic Assays

65
Q

Amylase (AMS)

-method that is a glucose coupled reaction and a hexokinase coupled reaction

A

Enzymatic Assays