Wednesday, March 21, 2012

ENZYMOLOGY - ANSWERS TO QUESTIONS

MATCH COLUMN B,C,& D WITH COLUMN A.

COLUMN A

1.AST - Aspartate Amino Transferase
2.ALT - Alanine Amino Transferase
3.CPK - Creatine PhosphoKinase
4.ACP - Acid Phosphatase
5.ALP - Alkaline Phosphatase
6.GGT - Gamma Glutamyl Transferase
7.CHS - Cholinesterase
8.AMS - Amylase
9.LPS - Lipase
10.LDH - Lactate Dehydrogenase

COLUMN B

A. BESSEY, LOWRY BROCK
B. SZASZ
C. CHROMOGENIC
D. WACKER ET AL
E. REITMAN AND FRANKEL
F. ELLMAN
G. BENEDICTS
H. KING ARMSTRONG
I. TANZER AND GILVARG
J. CHERRY CRANDALL
K. NOT IN THE LIST

COLUMN C

A. 5-35 U/L
B. 8-40 U/L
C. 6,000-12,000 U/L
D. F= up to 25 U/L
E. 60-160 U/L
F. M=90-190 U/L
G. 0.5- 1.9 U/L
H. 35-90 U/L
I. F= UP TO 130 U/L
J. M = up to 130 U/L
K. NOT IN THE LIST

COLUMN D

A. M.I.
B. HEPATITIS
C. ALCOHOLIC CIRRHOSIS
D. PROSTATIC CANCER
E. MUSCULAR DYSTROPHY
F. PESTICIDE POISONING
G. ACUTE PANCREATITIS
H. CHRONIC PANCREATITIS
I. MYASTHENIA GRAVIS
J. OSTEOMALACIA
K. NOT IN THE LIST

ANSWERS WILL BE POSTED ON JUNE. SORRY FOR THE DELAY.

ANSWERS:

COLUMN A COLUMN B COLUMN C COLUMN D

1. AST - Aspartate Amino Transferase - E, B, A
2.ALT - Alanine Amino Transferase - E, A, B
3.CPK - Creatine PhosphoKinase - I, I, E
4.ACP - Acid Phosphatase - A, H,/ G, D
5.ALP - Alkaline Phosphatase - A, H,/ F, I, J
6.GGT - Gamma Glutamyl Transferase - B, D, C
7.CHS - Cholinesterase - F, C, F
8.AMS - Amylase - C, E, G
9.LPS - Lipase - J, K, H
10.LDH - Lactate Dehydrogenase - D, H, A, B



ANSWERS TO QUESTIONS FOR RESEARCH CC2 – EXPTS 7-11 - Clinical Enzymology

CLINICAL CHEMISTRY 2 – LABORATORY HANDOUT AY 2011-2012

EXPERIMENT NO. 7 - ACID PHOSPHATASE

1. Discuss the principle of the test.

ACP catalyzes the hydrolysis of Paranitrophenylphosphate, which is colorless, at an acidic pH, to paranitrophenol, which is colored yellow, at 450 to 470 nanometers.

2. Why do we utilize the mentioned wavelength for ACP?

To be able to get the maximum reading of ACP in the sample.

3. What is the ideal specimen for the determination?

Citrated blood is ideal, but for the determination performed in the lab, it is serum.

4. Name sources of errors for ACP test

Hemolyzed serum falsely increases values

Turbid and icteric serum need serum blanking for accuracy

Some reagents are photosensitive, exposure to light would decrease values

Prolonged or shortened incubation time would increase and decrease values respectively

Alkaline pH would decrease values

Altered temperatures could either increase or decrease values

EXPERIMENT NO. 8- ALKALINE PHOSPHATASE

1. Discuss the principle of the test.

ALP catalyzes the hydrolysis of Paranitrophenylphosphate, which is colorless, to paranitrophenol, which is colored yellow, at 405 nanometers.

2. Name differences between ALP and ACP

category

ALP

ACP

pH

Basic or alkaline

acidic

Best specimen

Heparinized plasma (Calbreath)

Serum citrated plasma (Calbreath)

Tissue source

Same as ACP except for prostate, more on bone clin. significance

Prostate, platelets, bone, liver, spleen, kidneys, erythrocytes

Diagnostic significance

Hepatobiliary and bone disorders

Prostatic carcinoma

3. What is the reason for diluting serum if the absorbance is higher than 0.25?

For more precise and accurate measurement of the concentration of the unknown.

4. Why do we have to adjust the spectrophotometer to zero when we read unknown solutions?

To read out errors caused by the spectrophotometer and the reagent.

5. What is the best sample for this determination?

Unhemolyzed, clear, non-icteric, non-lipemic serum

EXPERIMENT NO. 9 – LACTATE DEGYDROGENASE DETERMINATION

1. Discuss the principle of the test.

LDH in the serum catalyzes the oxidation reduction of lactate to pyruvate, which is measured spectrophotometrically.

2. Give the reasons why serum LD determination cannot be refrigerated.

Because LD isoenzymes are thermolabile and are unstable at refrigerated temperatures. They would not be able to react accurately.

3. Why should there be timed intervals in the addition of 0.1N HCL?

So that the acid could react properly with the LDH in the sample.

4. Why should the incubation period be done exactly in 5 minutes?

Because incomplete reaction would occur if it is less than 5 minutes and more products would be formed when prolonged more than 5 minutes. This is at specified temperature and conditions.

5. Name sources of errors in this determination.

Hemolyzed serum increases result 100-150 X

Turbid, lipemic and icteric serum needs serum blanking for accuracy

Refrigerated blood samples lowers values

Prolonged or shortened incubation time at specified conditions could increase or decrease values respectively

Altered temperatures could either increase nor decrease values

EXPERIMENT NO. 10 – ALANINE AMINOTRANSFERASE DETERMINATION

1. Discuss the principle of the method.

ALT in the serum catalyzes the transfer of an amino acid group to a keto acid group to form pyruvate and L-glutamate. This is measured spectrophotometrically at 505-535 nanometers.

2. Aside from sodium hydroxide, what reagent could also be used to alkalinize the solution?

Potassium hydroxide

3. Why should the distilled water used in dissolving your NaOH pellets be CO2 free?

Because carbon dioxide can affect the transfer of the amino group to the keto acid group due to its carbon content. The carbon atom may act as an acceptor molecule in the reaction. This would falsely decrease your values.

4. Why do we use a semi-log graphing paper in plotting your calibration curve?

Because the it is simpler to use since the graphing paper will find the logarithms of the values beforehand.

EXPERIMENT NO. 11 – ASPARTATE AMINOTRANSFERASE DETERMINATION

1. State the principle of the test.

AST in the serum catalyzes the transfer of an amino acid group to a keto acid group to form oxaloacetate and L-glutamate. This is measured spectrophotometrically at 505-535 nanometers.

2. Name sources of error in this method.

Hemolyzed serum will increase values 10-15 X

Turbid, lipemic and icteric serum needs serum blanking for accuracy

Altered temperatures could either increase nor decrease values

Prolonged or shortened incubation time at specified conditions could increase or decrease values respectively

3. What is the purpose of allowing the reagents to come to room temperature.

The purpose is to allow the reagents to inactivate the reagents so that they could react properly.

4. Differentiate AST from ALT. Cite specific differences.

CRITERIA

AST

ALT

Substrate

L-aspartate & alpha-ketoglutarate

L-alanine & alpha-ketoglutarate

Old name

SGOT

SGPT

One of the end products

oxaloacetate

Pyruvate

Amount in inside serum

10-15 times

5-8 times

Major clinical significance

heart

Liver




5. What is the component of the SGOT substrate?

L -aspartate and alpha-ketoglutarate



Thursday, March 1, 2012

Electrolytes Quiz in Clinical Chemistry

I.MULTIPLE CHOICE( 1 pt. each)

Select the BEST answer by shading the box that corresponds to the letter of your choice in the answer sheet provided.

Choices for numbers 1 - 10: A. Sodium B. Chloride C. A and B D. NOTA

1. Diphenylcarbazone
2. Mercuric nitrate
3. Mercuric thioncyanate
4. Filtrate reagent consisting of uranyl acetate and magnesium acetate
5. Sodium chloride
6. Diluted acetic acid
7. Ferric nitrate
8. Ptoassium ferocyanide
9. Nitric acid
10. Potassium ferrocyanide

ANSWERS TO BE POSTED LATER.

SEARCH ENGINE

Google
 

COPYRIGHT

Except for the outside links, printing and copying of the articles contained herein should cite this site as the source. For commercial purposes, the permission of the author should be sought first. You can leave a comment in any of the posts. Thank you.