1.1 A 22-year-old Librarian went to her family doctor as she noticed that her skin was becoming moist quite often. She was told by her colleagues that she should visit her doctor as her eyes seemed to have become more prominent and that she was losing weight. On examination her doctor noted that she had a slightly enlarged thyroid gland.
Blood tests showed the following:
TSH < 0.1 mU/L
fT4 33 pmol/l
fT3 8 pmol/l
The scan perform showed an enlarged gland. Autoantibodies to thyroid peroxidase and thyroglobulin were present in the serum in high titre.
Discuss the above case with possible diagnosis. [6]
1.2 Explain what is meant by negative feedback inhibition using thyroid hormone as an example. [6]
2. Write notes on:
2.1 Cortisol
2.2 Testosterone [10]
3. Explain the principle used in RAST technique. [5]
4. Assays in an Endocrinology Laboratory are subject to assay robustness. Heterophile antibodies and the ‘hook effect’ are just 2 examples that affect assays. Using a hormone as an example comment on these and discuss how they are overcome. [8]
5. hCG is now widely used as a tumour marker as well to check for pregnancy. Discuss the structure of the hormone and name the hormone to which it is similar.
Explain the various tests that are used for its detection.
[8]
6. Discuss congenital adrenal hyperplasia and the tests involved in its detection. [8]
7. What disease does the doctor suspect if there is elevated catecholeamines? Give special precautions (of the patient) prior to the test.
[5]
8. Describe 5 of the following immunochemical techniques:
8.1 Radial Immunodiffusion
8.2 Immunoelectrophoresis :
8.3 Isoelectric focusing (IEF)
8.4 Western blot
8.5 Laurell ‘Rocket’ immunoelectrophoresis
8.6 Immunonephelometry
[10]
9. What are the following acronyms (with regard to radioactivity)?
9.1 R
9.2 RAD
9.3 REM
[3]
10. Write short notes on waste disposal of radioactive material. [7]
Thursday, March 24, 2011
chempath tut5
1. Carol is a 28 – year – old woman, pregnant for the first time, presented at the emergency room in possible labour. She appeared anxious with a pregnancy of unknown duration. Her blood pressure was raised and appeared to gain weight in the last few weeks.
Results:
Blood: Sodium 135 mmol/l
Potassium 3.5 mmol/l
Chloride 100 mmol/l
CO2 25 mmol/l
Urea 2.8 mmol/l
Creatinine 74 umol/l
Urine: glucose + protein 3+
Amniotic fluid: L/S ratio 1.7 PG +
1.1 Judging from the results above, do they reflect a normal pregnancy?
1.2 Comment on the maturity of the foetus.
1.3 Briefly describe the testing for neural tube defect. [14]
2. There was much media speculation of meningitis in this country as many patients had
signs and symptoms of the condition and a few patients died from the illness.
2.1 Explain the collection of specimen of choice. [2]
2.2Discuss the various tubes taken and the reasons thereof. [4]
2.3 Name all the tests done in a Chemical Pathology lab for CSF analysis and
explain the significance of each test. [16]
4 3.1 In occult blood analysis discuss the interfering factors that give false
results. [2]
3.2 What are the limitations to the sensitivity and specificity of this assay? [2]
3.3 Explain the clinical usefulness of a faecal fat test. Note special requirements for the assay. [4]
3.4 Discuss the various methods employed for occult blood analysis. [6]
4.1 Certain requirements must be met for an enzyme to be suitable for EIA.
Discuss. [6]
4.2 Explain how immunonephelometry can be used to measure IgM. [6]
4.3 Differentiate between antigen and antibody detection using the sandwich technique. [6]
5. Dr Peter N is a pathologist who has completed the qualification as an endocrinologist. He wishes to leave the state hospital and open up a RIA laboratory. Name all the requirements that are necessary for this venture. [8]
Results:
Blood: Sodium 135 mmol/l
Potassium 3.5 mmol/l
Chloride 100 mmol/l
CO2 25 mmol/l
Urea 2.8 mmol/l
Creatinine 74 umol/l
Urine: glucose + protein 3+
Amniotic fluid: L/S ratio 1.7 PG +
1.1 Judging from the results above, do they reflect a normal pregnancy?
1.2 Comment on the maturity of the foetus.
1.3 Briefly describe the testing for neural tube defect. [14]
2. There was much media speculation of meningitis in this country as many patients had
signs and symptoms of the condition and a few patients died from the illness.
2.1 Explain the collection of specimen of choice. [2]
2.2Discuss the various tubes taken and the reasons thereof. [4]
2.3 Name all the tests done in a Chemical Pathology lab for CSF analysis and
explain the significance of each test. [16]
4 3.1 In occult blood analysis discuss the interfering factors that give false
results. [2]
3.2 What are the limitations to the sensitivity and specificity of this assay? [2]
3.3 Explain the clinical usefulness of a faecal fat test. Note special requirements for the assay. [4]
3.4 Discuss the various methods employed for occult blood analysis. [6]
4.1 Certain requirements must be met for an enzyme to be suitable for EIA.
Discuss. [6]
4.2 Explain how immunonephelometry can be used to measure IgM. [6]
4.3 Differentiate between antigen and antibody detection using the sandwich technique. [6]
5. Dr Peter N is a pathologist who has completed the qualification as an endocrinologist. He wishes to leave the state hospital and open up a RIA laboratory. Name all the requirements that are necessary for this venture. [8]
chempath tut4
1. Multiple choice: Choose the correct answer.
1.1 Characteristic X-rays are emitted during the nuclear reaction involving:
a. gamma decay
b. electron capture
c. positron decay
d. negatron decay
e. none of the above
1.2 In quantitative immunoassays the single most important factor responsible
for success or failure is:
a. affinity
b. titer
c. monoclonal property
d. antibody absorption
e. specificity
1.3 Which of the following compounds are often monitored by competitive
binding assays?
a. therapeutic drugs
b. protein hormones
c. estrogens
d. antibiotics
e. all of the above
1.4 Elevated T4 and T3 uptake together suggest the likelihood of :
a. hyperthyroidism
b. decreased TBG
c. hypothyroidism
d. decreased TSB
e. None of the above
1.5 TRH is secreted by the :
a. anterior pituitary
b. posterior pituitary
c. adrenal cortex
d. thyroid gland
e. hypothalamus
1.6 Steroid hormones are transported in blood :
a. Covalently bound to protein
b. Are free hormones
c. Non- covalently bound to specific proteins
d. In red blood cells
e. None of the above.
1.7 Which of the following describes the chemical characteristic of an antibody?
a. Carbohydrate
b. protein
c. lipid
d. electrolyte
e. ligand
1.8 Immunonephelometry is based upon the principle that :
a. antigen and antibody form small complexes in antibody excess
b. antigen and antibody form complexes in antigen excess
c. antigen and antibody react to form precipitin line
d. antigen and antibody form large complexes which precipitate
e. antigen and antibody form large lattice structures, which precipitate.
1.9 In double diffusion, immune precipitation reactions occur when two lines cross
each other: the reaction is one of:
a. antigen identity
b. identity
c. partial identity
d. non – identity
e. antibody identity
1.10 Which of the following factors affects antigenicity?
a. chemical nature
b. size
c. conformation
d. genetics
e. all are correct
[10]
2. Write an essay on the steps involved in the practical performance of RIA.
[12]
3. State whether the following statements are true or false. If false give an
explanation.
3.1 Steroid hormones are covalently bound to specific proteins and transported in blood.
3.2 When an antigen and antibody form small complexes in antigen excess, it is based on the principle of immunonephelometry.
3.3 Polyclonal antibodies are predominantly of the IgM type.
3.4 The posterior pituitary is also known as neurohypophysis
[6]
4. Certain requirements must be met for an enzyme to be suitable for EIA.
Discuss. [6]
5. Explain how immunonephelometry can be used to measure IgM. [6]
6. Explain what you would do if placed in the following situation:
Thembi is a patient whose blood sample was taken in the Endocrine clinic a month ago. She apparently phoned the clinic but was closed. Thus she called the laboratory for the result. You happen to answer the phone. You take her details and from the computer there was a TSH result of > 100 umol/l.
[2]
7. Draw a typical RIA graph for which a test like cortisol is plotted. [2]
8. Write short notes on waste disposal of radioactive material. [7]
9. What would the final dilution of serum be if 0.2ml was added to 39.8 ml of distilled water and then 1 ml of this was added to 7 mls of a reagent solution? [5]
10. Explain how you would prepare 40 ml of each of the following standards using a stock solution on 40g/l:
10.1 10 g/l
10.2 4 g/l [4]
1.1 Characteristic X-rays are emitted during the nuclear reaction involving:
a. gamma decay
b. electron capture
c. positron decay
d. negatron decay
e. none of the above
1.2 In quantitative immunoassays the single most important factor responsible
for success or failure is:
a. affinity
b. titer
c. monoclonal property
d. antibody absorption
e. specificity
1.3 Which of the following compounds are often monitored by competitive
binding assays?
a. therapeutic drugs
b. protein hormones
c. estrogens
d. antibiotics
e. all of the above
1.4 Elevated T4 and T3 uptake together suggest the likelihood of :
a. hyperthyroidism
b. decreased TBG
c. hypothyroidism
d. decreased TSB
e. None of the above
1.5 TRH is secreted by the :
a. anterior pituitary
b. posterior pituitary
c. adrenal cortex
d. thyroid gland
e. hypothalamus
1.6 Steroid hormones are transported in blood :
a. Covalently bound to protein
b. Are free hormones
c. Non- covalently bound to specific proteins
d. In red blood cells
e. None of the above.
1.7 Which of the following describes the chemical characteristic of an antibody?
a. Carbohydrate
b. protein
c. lipid
d. electrolyte
e. ligand
1.8 Immunonephelometry is based upon the principle that :
a. antigen and antibody form small complexes in antibody excess
b. antigen and antibody form complexes in antigen excess
c. antigen and antibody react to form precipitin line
d. antigen and antibody form large complexes which precipitate
e. antigen and antibody form large lattice structures, which precipitate.
1.9 In double diffusion, immune precipitation reactions occur when two lines cross
each other: the reaction is one of:
a. antigen identity
b. identity
c. partial identity
d. non – identity
e. antibody identity
1.10 Which of the following factors affects antigenicity?
a. chemical nature
b. size
c. conformation
d. genetics
e. all are correct
[10]
2. Write an essay on the steps involved in the practical performance of RIA.
[12]
3. State whether the following statements are true or false. If false give an
explanation.
3.1 Steroid hormones are covalently bound to specific proteins and transported in blood.
3.2 When an antigen and antibody form small complexes in antigen excess, it is based on the principle of immunonephelometry.
3.3 Polyclonal antibodies are predominantly of the IgM type.
3.4 The posterior pituitary is also known as neurohypophysis
[6]
4. Certain requirements must be met for an enzyme to be suitable for EIA.
Discuss. [6]
5. Explain how immunonephelometry can be used to measure IgM. [6]
6. Explain what you would do if placed in the following situation:
Thembi is a patient whose blood sample was taken in the Endocrine clinic a month ago. She apparently phoned the clinic but was closed. Thus she called the laboratory for the result. You happen to answer the phone. You take her details and from the computer there was a TSH result of > 100 umol/l.
[2]
7. Draw a typical RIA graph for which a test like cortisol is plotted. [2]
8. Write short notes on waste disposal of radioactive material. [7]
9. What would the final dilution of serum be if 0.2ml was added to 39.8 ml of distilled water and then 1 ml of this was added to 7 mls of a reagent solution? [5]
10. Explain how you would prepare 40 ml of each of the following standards using a stock solution on 40g/l:
10.1 10 g/l
10.2 4 g/l [4]
chempath tut3
1.1 Which of the following describes the chemical characteristic of an antibody?
a. carbohydrate
b. lipid
c. protein
d. electrolyte
e. ligand
1.2 Immunonephelometry is based upon the principle that :
a. antigen and antibody form complexes in antigen excess
b. antigen and antibody react to form precipitin line
c. antigen and antibody form small complexes in antibody excess
d. antigen and antibody form large complexes which precipitate
e. antigen and antibody form large lattice structures, which precipitate.
1.3 In double diffusion, immune precipitation reactions occur when two lines cross each other: the reaction is one of:
a. antigen identity
b. identity
c. partial identity
d. antibody identity
e. non – identity
1.4 Which of the following factors affects antigenicity?
a. chemical nature
b. size
c. conformation
d. genetics
e. all are correct
1.5 Laurell ‘ rocket’ immunoelectrophoresis requires :
a. agarose
b. purified antigen
c. ac power supply
d. agarose mixed with antibody
e. none are correct
Page 1 of 4
1.6 Which of the following compounds are not often monitored by competitive binding assays?
a. therapeutic drugs
b. protein hormones
c. estrogens
d. electrolytes
e. antibiotics
1.7 How much CaSO4 (Ca = 40; S = 32; O = 16) should be weighed to prepare one litre of a 0.5 M solution of CaSO4?:
a. 6.8 g
b. 13 g
c. 27.2 g
d. 34 g
e. 68 g
1.8 A tube contains the following:
Serum : 0.25 ml Saline : 0.75 ml Antigen : 1.0 ml
What is the serum dilution?
a. 1:2
b. 1:4
c. 1:7
d. 1:8
e. 1:16
1.9 How many ml of concentrated HCl (specific gravity = 1.2 ; 30 purity) would be needed to prepare one litre of a 4 M solution
( atomic weight H = 1 Cl = 35 )?:
a. 72 ml
b. 86.4 ml
c. 144 ml
d. 200 ml
e. 400 ml
Page 2 of 4
1.10 A crystal scintillation detector is primarily used for detecting radionuclides emitting:
a. positrons
b. gamma rays
c. negatrons
d. X – rays
e. Ultraviolet light
1.11 125I is used as a label because:
a. it has high specific activity
b. it is a high energy emitter
c. it has a long half-life
d. all of the above
e. none of the above.
[11]
2. Write an essay on the steps involved in the practical performance of RIA. Give a full explanation on each step i.e. reasons where possible. [12]
3. Explain the principle used in RAST technique. [4]
4. Describe 5 of the following immunochemical techniques:
4.1 Radial Immunodiffusion
4.2 Immunoelectrophoresis :
4.3 Isoelectric focusing ( IEF )
4.4 Western blot
4.5 Laurell ‘Rocket’ immunoelectrophoresis
4.6 Immunonephelometry
[10]
Page 3 of 4
5. Explain all the requirements for labels in immunoassays. [5]
6. Draw a typical RIA graph for which a test like cortisol is plotted.
[2]
7. Discuss how the entry of radioactivity may be prevented. [6]
8. What are the following acronyms (with regard to radioactivity)?:
8.1 R
8.2 RAD
8.3 REM
[3]
9. Write short notes on waste disposal of radioactive material. [7]
a. carbohydrate
b. lipid
c. protein
d. electrolyte
e. ligand
1.2 Immunonephelometry is based upon the principle that :
a. antigen and antibody form complexes in antigen excess
b. antigen and antibody react to form precipitin line
c. antigen and antibody form small complexes in antibody excess
d. antigen and antibody form large complexes which precipitate
e. antigen and antibody form large lattice structures, which precipitate.
1.3 In double diffusion, immune precipitation reactions occur when two lines cross each other: the reaction is one of:
a. antigen identity
b. identity
c. partial identity
d. antibody identity
e. non – identity
1.4 Which of the following factors affects antigenicity?
a. chemical nature
b. size
c. conformation
d. genetics
e. all are correct
1.5 Laurell ‘ rocket’ immunoelectrophoresis requires :
a. agarose
b. purified antigen
c. ac power supply
d. agarose mixed with antibody
e. none are correct
Page 1 of 4
1.6 Which of the following compounds are not often monitored by competitive binding assays?
a. therapeutic drugs
b. protein hormones
c. estrogens
d. electrolytes
e. antibiotics
1.7 How much CaSO4 (Ca = 40; S = 32; O = 16) should be weighed to prepare one litre of a 0.5 M solution of CaSO4?:
a. 6.8 g
b. 13 g
c. 27.2 g
d. 34 g
e. 68 g
1.8 A tube contains the following:
Serum : 0.25 ml Saline : 0.75 ml Antigen : 1.0 ml
What is the serum dilution?
a. 1:2
b. 1:4
c. 1:7
d. 1:8
e. 1:16
1.9 How many ml of concentrated HCl (specific gravity = 1.2 ; 30 purity) would be needed to prepare one litre of a 4 M solution
( atomic weight H = 1 Cl = 35 )?:
a. 72 ml
b. 86.4 ml
c. 144 ml
d. 200 ml
e. 400 ml
Page 2 of 4
1.10 A crystal scintillation detector is primarily used for detecting radionuclides emitting:
a. positrons
b. gamma rays
c. negatrons
d. X – rays
e. Ultraviolet light
1.11 125I is used as a label because:
a. it has high specific activity
b. it is a high energy emitter
c. it has a long half-life
d. all of the above
e. none of the above.
[11]
2. Write an essay on the steps involved in the practical performance of RIA. Give a full explanation on each step i.e. reasons where possible. [12]
3. Explain the principle used in RAST technique. [4]
4. Describe 5 of the following immunochemical techniques:
4.1 Radial Immunodiffusion
4.2 Immunoelectrophoresis :
4.3 Isoelectric focusing ( IEF )
4.4 Western blot
4.5 Laurell ‘Rocket’ immunoelectrophoresis
4.6 Immunonephelometry
[10]
Page 3 of 4
5. Explain all the requirements for labels in immunoassays. [5]
6. Draw a typical RIA graph for which a test like cortisol is plotted.
[2]
7. Discuss how the entry of radioactivity may be prevented. [6]
8. What are the following acronyms (with regard to radioactivity)?:
8.1 R
8.2 RAD
8.3 REM
[3]
9. Write short notes on waste disposal of radioactive material. [7]
chempath tut2
1.1 How many milliliters of concentrated HNO3 (sp gravity 1.42 g/ml; assay =
85%) are required to prepare 5 litres of 0.5 NO3? [5]
1.2 What amount of NaOH is required to obtain 100 mg of Na? [4]
2. Explain the following statements:
2.1 Foreign antigens and antisera may leave little permanent damage.
2.2 Labels must not be present in body fluids in high concentration.
2.3 The lab may required samples taken from animals.
2.4 The thyroid gland is one organ that is often neglected and is an essential in its numerous functions
2.5 A overproduction of VMA / HMA may be precipitated by tumors [5]
3. Discuss 4 of the listed techniques / assays that may be encountered in immunoassays. Provide full names.
3.1 ELISA
3.2 IRMA
3.3 EMIT
3.4 SLFIA
3.5 FPIA [10]
4. Using GH (Growth hormone) as an example explain the concept of competitive binding. Draw various diagrams to depict various levels of GH.
[15]
5. Discuss the concept of chemiluminescence. Explain the origin and how it may
be eliminated. [3]
6. If you were to establish a lab for RIA state all the necessary precautions you would take to ensure you would obtain the specified license to practice. [7]
7. Catherine is a librarian who went to her GP as she was not her usual self for a number of months. Her weight deteriorated and her eyes began bulging. On examination, her doctor observed that she had a slightly enlarged thyroid gland.
Blood tests showed the following:
TSH < 0.1 mU/L
fT4 33 pmol/l
fT3 12 pmol/l
7.1 Discuss the above case with possible diagnosis. [6]
7.2 Give the possible treatment [1]
8. Castor Semenya made the headlines last year and later the topic was very sensitive due to its very nature. Explain the concept from a molecular level and its implications. [6]
9.1 Differentiate between the drug chemical name, generic and trade name. Give an example [6]
9.2 Briefly explain all the factors which may affect drug level assays and interpretation [7]
85%) are required to prepare 5 litres of 0.5 NO3? [5]
1.2 What amount of NaOH is required to obtain 100 mg of Na? [4]
2. Explain the following statements:
2.1 Foreign antigens and antisera may leave little permanent damage.
2.2 Labels must not be present in body fluids in high concentration.
2.3 The lab may required samples taken from animals.
2.4 The thyroid gland is one organ that is often neglected and is an essential in its numerous functions
2.5 A overproduction of VMA / HMA may be precipitated by tumors [5]
3. Discuss 4 of the listed techniques / assays that may be encountered in immunoassays. Provide full names.
3.1 ELISA
3.2 IRMA
3.3 EMIT
3.4 SLFIA
3.5 FPIA [10]
4. Using GH (Growth hormone) as an example explain the concept of competitive binding. Draw various diagrams to depict various levels of GH.
[15]
5. Discuss the concept of chemiluminescence. Explain the origin and how it may
be eliminated. [3]
6. If you were to establish a lab for RIA state all the necessary precautions you would take to ensure you would obtain the specified license to practice. [7]
7. Catherine is a librarian who went to her GP as she was not her usual self for a number of months. Her weight deteriorated and her eyes began bulging. On examination, her doctor observed that she had a slightly enlarged thyroid gland.
Blood tests showed the following:
TSH < 0.1 mU/L
fT4 33 pmol/l
fT3 12 pmol/l
7.1 Discuss the above case with possible diagnosis. [6]
7.2 Give the possible treatment [1]
8. Castor Semenya made the headlines last year and later the topic was very sensitive due to its very nature. Explain the concept from a molecular level and its implications. [6]
9.1 Differentiate between the drug chemical name, generic and trade name. Give an example [6]
9.2 Briefly explain all the factors which may affect drug level assays and interpretation [7]
chempath tut1
1. Multiple choice: choose the correct answer; showing how you obtained
your answer.
1.1 What is the molarity of a solution that contains 18.7g of KCl in
500 ml?
A. 0.1
B. 0.5
C. 1.0
D. 5.0
1.2 How much 95% alcohol is required to prepare 5 L 70% alcohol?
A. 2.4 L
B 3.5 L
C. 3.7 L
D. 4.4 L
1.3. How many milliliters of concentrated H2SO4 are required to prepare 10L of 0.1 N H2SO4?
A. 1.84
B. 9.20
C. 27.5
D. 54.4
1.4 How many grams of Na0H are required to prepare 2500 mL of a 4 M solution?]
A. 40
B. 100
C. 160
D. 400
1.5 What is the relative centrifugal force of a centrifuge operating at 1500 rpm with a radius of 10 cm?
A. 625
B. 699
C. 252
D. 6988
1.6 Which of the following weighs the most?
A. 0.1 ng
B. 0.01 g
C. 1.0 mg
D. 1000 pg
1.7 What amount of NaCl is needed to obtain 50 mg Cl?
A. 19.6 mg
B. 30.3 mg
C. 50.0 mg
D. 82.4 mg [7 x 3 = 21]
2.1 Explain the term occult blood, with details of the type of specimen
required for analysis. [3]
2.2 Give 3 cases where one can get a positive result. [3]
2.3 Explain how one can obtain a false positive result. [1]
2.4 Name a type of occult blood test that may be obtained from suppliers / manufacturers. [1]
3. Discuss the assessment of foetal maturity and reasons why amniotic fluid is a choice of specimen for analysis. [5]
4. Differentiate between antigen and antibody detection using the sandwich technique. [6]
5. Dr Peter N is a Pathologist who has completed the qualification as an endocrinologist. He wishes to leave the state hospital and open up a RIA laboratory. Name all the requirements that are necessary for this venture. [8]
6. Draw a fully labelled diagram to illustrate a competitive binding assay. [5]
7. With the aid of separate diagrams show how standard curves are generated in a radioimmunoassay and also how patients’ results are obtained from the graph. [12]
8. Explain counting and maintaining consistency in RIA measurements. [6]
9. Describe 5 of the following immunochemical techniques:
9.1 Radial Immunodiffusion
9.2 Immunoelectrophoresis
9.3 Isoelectric focusing ( IEF )
9.4 Western blot
9.5 Laurell ‘Rocket’ immunoelectrophoresis
9.6 Immunonephelometry
[10]
Additional information:
Molar mass:
K 39 Cl 35.5 H 1 S 32 O 16 Na 23
H2SO4 (sp gr = 1.84g/mL; assay = 97%)
your answer.
1.1 What is the molarity of a solution that contains 18.7g of KCl in
500 ml?
A. 0.1
B. 0.5
C. 1.0
D. 5.0
1.2 How much 95% alcohol is required to prepare 5 L 70% alcohol?
A. 2.4 L
B 3.5 L
C. 3.7 L
D. 4.4 L
1.3. How many milliliters of concentrated H2SO4 are required to prepare 10L of 0.1 N H2SO4?
A. 1.84
B. 9.20
C. 27.5
D. 54.4
1.4 How many grams of Na0H are required to prepare 2500 mL of a 4 M solution?]
A. 40
B. 100
C. 160
D. 400
1.5 What is the relative centrifugal force of a centrifuge operating at 1500 rpm with a radius of 10 cm?
A. 625
B. 699
C. 252
D. 6988
1.6 Which of the following weighs the most?
A. 0.1 ng
B. 0.01 g
C. 1.0 mg
D. 1000 pg
1.7 What amount of NaCl is needed to obtain 50 mg Cl?
A. 19.6 mg
B. 30.3 mg
C. 50.0 mg
D. 82.4 mg [7 x 3 = 21]
2.1 Explain the term occult blood, with details of the type of specimen
required for analysis. [3]
2.2 Give 3 cases where one can get a positive result. [3]
2.3 Explain how one can obtain a false positive result. [1]
2.4 Name a type of occult blood test that may be obtained from suppliers / manufacturers. [1]
3. Discuss the assessment of foetal maturity and reasons why amniotic fluid is a choice of specimen for analysis. [5]
4. Differentiate between antigen and antibody detection using the sandwich technique. [6]
5. Dr Peter N is a Pathologist who has completed the qualification as an endocrinologist. He wishes to leave the state hospital and open up a RIA laboratory. Name all the requirements that are necessary for this venture. [8]
6. Draw a fully labelled diagram to illustrate a competitive binding assay. [5]
7. With the aid of separate diagrams show how standard curves are generated in a radioimmunoassay and also how patients’ results are obtained from the graph. [12]
8. Explain counting and maintaining consistency in RIA measurements. [6]
9. Describe 5 of the following immunochemical techniques:
9.1 Radial Immunodiffusion
9.2 Immunoelectrophoresis
9.3 Isoelectric focusing ( IEF )
9.4 Western blot
9.5 Laurell ‘Rocket’ immunoelectrophoresis
9.6 Immunonephelometry
[10]
Additional information:
Molar mass:
K 39 Cl 35.5 H 1 S 32 O 16 Na 23
H2SO4 (sp gr = 1.84g/mL; assay = 97%)
Tuesday, March 22, 2011
stormy clot
This is one of the tests done to identify Clostridium perfringens. A litmus milk is used. Litmus milk is a light purple liquid aliquoted in a bijou bottle. Prior to us for THIS test, sterile rusty nails are put into it. Sterile so that it is not contaminated. Rusty nails so that an anaerobic atmosphere is created. Remember that Clostridium is an aerotolerant anaerobe, i.e. it will not die on exposure to oxygen.
Inoculate the litmus milk with the test organism. Incubate anaerobically at 37 degrees for 18-24 hours. You can use a candle jar.
After incubation, examine for the presence of a stormy clot. I will first describe how the stormy clot is formed, and then describe its appearance.
Lactose in the milk is fermented. Acid and gas are produced. This acid causes coagulation of the casein. Casein combines with the gas to produce the distinctive and characteristic stormy clot.
A stormy clot is the production of whitish cloud like coagulation at the top of the litmus milk. Below that is the paler litmus milk. It is almost like the clouds we see at dusk, large white cumulonimbus clouds above a very pretty pale blue sky.
Inoculate the litmus milk with the test organism. Incubate anaerobically at 37 degrees for 18-24 hours. You can use a candle jar.
After incubation, examine for the presence of a stormy clot. I will first describe how the stormy clot is formed, and then describe its appearance.
Lactose in the milk is fermented. Acid and gas are produced. This acid causes coagulation of the casein. Casein combines with the gas to produce the distinctive and characteristic stormy clot.
A stormy clot is the production of whitish cloud like coagulation at the top of the litmus milk. Below that is the paler litmus milk. It is almost like the clouds we see at dusk, large white cumulonimbus clouds above a very pretty pale blue sky.
comments on micro3 practical test one
I can't decide if I am amused or upset about the stuff you did in your prac test. These are some comments I noted:
Many organisms can grow on SAB. You cannot assume that if there is growth, that it is definitely a yeast
Biochemical tests that you set up must tie in with what you observed in your Gram stain
I have asked repeatedly that you do not describe the colour of the colonies or organisms. It is either Gram positive or negative, or LF or NLF
You need to interpret the results of the biochemical tests as being either positive or negative. At this stage of your studies, you should not be saying/describing the colours seen
MSA cannot be positive or negative. You need to state mannitol fermentation or no mannitol fermentation
LF on MacConkey are large glossy mucoid colonies
Escherichia coli 0157H7 can only be determined by serotyping the E coli. It is not determined by putting up sugars
CTA sugars are not used for GNB identification.
Above all else, please listen to me in lectures, during practical sessions, etc. I am not wasting your time by telling you stuff.
Many organisms can grow on SAB. You cannot assume that if there is growth, that it is definitely a yeast
Biochemical tests that you set up must tie in with what you observed in your Gram stain
I have asked repeatedly that you do not describe the colour of the colonies or organisms. It is either Gram positive or negative, or LF or NLF
You need to interpret the results of the biochemical tests as being either positive or negative. At this stage of your studies, you should not be saying/describing the colours seen
MSA cannot be positive or negative. You need to state mannitol fermentation or no mannitol fermentation
LF on MacConkey are large glossy mucoid colonies
Escherichia coli 0157H7 can only be determined by serotyping the E coli. It is not determined by putting up sugars
CTA sugars are not used for GNB identification.
Above all else, please listen to me in lectures, during practical sessions, etc. I am not wasting your time by telling you stuff.
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