Hi Ms Chew... i read up on some biochemical tests avaliable in my lab... so here they are:
The Indole Test
The organism is inoculated into tryptone broth. Indole positive bacteria such as Escherichia coli produce tryptophanase, an enzyme that cleaves tryptophan, producing indole and other products. When Kovac's reagent is added to a broth with indole in it, a dark pink color develops. The indole test must be read by 48 hours of incubation because the indole can be further degraded if prolonged incubation occurs. The acidic pH produced by Escherichia coli limits its growth.
The Citrate Test
The citrate test utilizes Simmon's citrate media to determine if a bacterium can grow utilizing citrate as its sole carbon and energy source. Simmon's media contains bromthymol blue, a pH indicator with a range of 6.0 to 7.6. Bromthymol blue is yellow at acidic pH's (around 6), and gradually changes to blue at more alkaline pH's (around 7.6). Uninoculated Simmon's citrate agar has a pH of 6.9, so it is an intermediate green color. Growth of bacteria in the media leads to development of a Prussian blue color (positive citrate). Enterobacter and Klebsiella are citrate positive while E.coli is negative.
Triple sugar Iron (TSI) - & Hydrogen sulfide production (H2S)
Examines fermentation of glucose, lactose, and sucrose and checks if hydrogen sulfide is produced in the process. A pH indicator will change the color of the media in response to fermentation. Where the color change occurs in the tube will indicate what sugar or sugars were fermented. The presence of a black color indicates that H2S was produced. To inoculate, use a needle to stab agar and then uses a loop to streak the top slated region.
SLANT COLOR:
Interpretation
RED
Does not ferment either lactose or sucrose
YELLOW
Ferments lactose and/or sucrose
BUTT COLOR/CONDITION:
Interpretation
RED
No fermentation of glucose
YELLOW
Some fermentation of glucose has occurred, acid has been produced
GAS FORMED
Seen as cracks in the agar, bubbles, or the entire slant may be pushed out of the tube.
BLACK
H2S has been produced
Motility test
This test can be used to check for the ability of bacteria to migrate away from a line of inoculation thanks to physical features like flagella. To perform this test, the bacterial sample is inoculated into motility media using a needle. Simply stab the media in as straight a line as possible and withdraw the needle very carefully to avoid destroying the straight line. After incubating the sample for 24-48 hours observations can be made. Check to see if the bacteria have migrated away from the original line of inoculation. If migration away from the line of inoculation is evident then you can conclude that the test organism is motile (positive test). Lack of migration away from the line of inoculation indicates a lack of motility (negative test result).
Oxidation - fermentation tests (OF test)
This biooxidation test is used to decide the oxidative or fermentative metabolism of a carbohydrate or its non-utilization.
A. OF Media (green colored)
Use for Gram-negative rods.
yellow = positive green or blue = negative
B. CTA Media (orange colored)
Use for Gram-positive cocci.
yellow = positive orange or red = negative
Nitrate test
This is a test used to detect the presence of nitrite. Some facultative bacteria convert nitrate to nitrite by removing an oxygen from nitrate using the enzyme nitratase.
Interpretation:
After incubation, the broth must be turbid. A clear broth indicates that your organism did not grow and cannot be tested. Add several drops of 2% acetic acid to the broth culture. Shake gently. A positive reaction is shown by production of a dark color.
Friday, August 31, 2007
Saturday, August 25, 2007
Name :Dorene Chen
Hello people, it's my turn to write blog again.
To date, I have been to biochemistry (done blog), haematology and serology department.
Serology
The tests I will be going through are:
1)AMC (Anti microsomal/thyroid peroxidase antibodies = same thing but different name)
2)ATG (Antibodies to ThyroGlobulin).
3)ANF slide (Anti nuclear Factor)
AMC/ ATG testing ( methods are the same so i join them together =D)
AMC/ATG testing tests for presence of autoimmune antibodies. It uses gelatin particles sensitized with human Thyroglobulin (Tg) or thyroid peroxidase (TPO) antigen for agglutination. serum containing specific antibodies will react with gelatin particle to form a smooth mat of agglutinated particles in the microtitration plate (aka "ELISA" plate) testing tests for
Autoimmune thyroid disease is autoimmune disease of the thyroid gland in which the patient's own immune system attacks his own thyroid. In patients suffering from this disease may secrete anti thyroglobulin and Anti microsomal antibodies against their own thyroid antigen (thyroglobulin, microsomal/thyroid peroxidase antigen are found in thyroid).
Thyroglobulin (Tg) is a protein found and produced by thyroid and T3, T4 are produced from this protein. T3, T4 are hormones that aids in transporting protein, controlling metabolism and they affect almost every process in the body.
Microsomal/ thyroid peroxidase (TPO) is an enzyme in thyroid that aids in the function of producing T3, T4 through oxidising iodide compounds in blood and to incorporate the oxidized iodide compounds into T3, T4.
Method (uses multi-well/microtitration plate aka "ELISA" plate):
Note: the picture above shows only the reagents to add in one row.
1)add 50µL of sample diulent to 1st well. Add 75 µL to 2nd-6th well.
2) add 10µL of positive control to first well. add 10 µL of sample to other row in the multiwell plate.
3) Do serial dilution by taking 25µL of suspension from 1st well into 2nd well. pipette and mix well. From 2nd well, pipette another 25 µL to 3rd. repeat until 6th well. discard away the 25µL from the 6th well.
4 ) Add 25µL unsensitized particles ( these particles will not cause any reaction, act as control) only to the 2nd well of the control.
5) Add 25 µL sensitized particles (these particles cause agglutination when antibodies is present) to the other well.
6) Incubate for 3 hours.
Hello people, it's my turn to write blog again.
To date, I have been to biochemistry (done blog), haematology and serology department.
Serology
The tests I will be going through are:
1)AMC (Anti microsomal/thyroid peroxidase antibodies = same thing but different name)
2)ATG (Antibodies to ThyroGlobulin).
3)ANF slide (Anti nuclear Factor)
AMC/ ATG testing ( methods are the same so i join them together =D)
AMC/ATG testing tests for presence of autoimmune antibodies. It uses gelatin particles sensitized with human Thyroglobulin (Tg) or thyroid peroxidase (TPO) antigen for agglutination. serum containing specific antibodies will react with gelatin particle to form a smooth mat of agglutinated particles in the microtitration plate (aka "ELISA" plate) testing tests for
Autoimmune thyroid disease is autoimmune disease of the thyroid gland in which the patient's own immune system attacks his own thyroid. In patients suffering from this disease may secrete anti thyroglobulin and Anti microsomal antibodies against their own thyroid antigen (thyroglobulin, microsomal/thyroid peroxidase antigen are found in thyroid).
Thyroglobulin (Tg) is a protein found and produced by thyroid and T3, T4 are produced from this protein. T3, T4 are hormones that aids in transporting protein, controlling metabolism and they affect almost every process in the body.
Microsomal/ thyroid peroxidase (TPO) is an enzyme in thyroid that aids in the function of producing T3, T4 through oxidising iodide compounds in blood and to incorporate the oxidized iodide compounds into T3, T4.
Method (uses multi-well/microtitration plate aka "ELISA" plate):
Note: the picture above shows only the reagents to add in one row.1)add 50µL of sample diulent to 1st well. Add 75 µL to 2nd-6th well.
2) add 10µL of positive control to first well. add 10 µL of sample to other row in the multiwell plate.
3) Do serial dilution by taking 25µL of suspension from 1st well into 2nd well. pipette and mix well. From 2nd well, pipette another 25 µL to 3rd. repeat until 6th well. discard away the 25µL from the 6th well.
4 ) Add 25µL unsensitized particles ( these particles will not cause any reaction, act as control) only to the 2nd well of the control.
5) Add 25 µL sensitized particles (these particles cause agglutination when antibodies is present) to the other well.
6) Incubate for 3 hours.
Positive result: Form large ring (dark purple color background with light purple ring shape in the center cause by agglutination). For very strong reaction, the dark purple color background disappears completely.
Negative result: Button shaped (Purple color throughout)
Friday, August 17, 2007
Name: Teng Cassandrea
Laboratory: Biochemistry
Neonatal serum bilirubin
o Breakdown of hemoglobin>>globin + heme
o Globin + iron >>re-utilized, leaving porphyrin portion of heme
o Breakdown of heme occurs in reticuloendothelial system
o Porphyrin ring opened up to form biliverdin
o Biliverdin>>reduced to bilirubin
o Bilirubin>>transported in plasma to liver>> conjugated with glucuronic acid
o Conjugated bilirubin>>further broken down in the intestines by intestinal bacteria>>urobilinogen
o Various reduction products of bilirubin may be absorbed from intestine>>returned to liver for re-excretion
o Any overload or blockage of this system raises levels of plasma total bilirubin
At least 80% of plasma bilirubin is unconjugated or indirect. When bilirubin in the blood is excessive, it deposits in the tissues, which causes jaundice. It may be caused by:
o Production of bilirubin more than the normal liver can excrete (e.g. hemolytic disease).
o Failure of the damaged liver to excrete the bilirubin produced in normal amounts (e.g. hepatitis).
o Obstruction of the excretory ducts in liver.
Neonatal physiological jaundice is common in newborns due to an immature fetal liver. The liver cannot conjugate all the bilirubin produced because of deficient enzymes. This jaundice however, disappears as the liver matures and enzymes function improves.
Upon receiving the patient samples, the samples are spun down so that the serum can be obtained for an accurate reading. The samples are that loaded into the REICHERT UNISTAT Bilirubinometer using a curvette. The readings are the recorded onto the request form and left to be verified.
G6PD screening test
o G6PD>>key enzyme in hexose monophosphate pathwayàrequired for formation of NADPH.
o NADPH>>essential for maintaining integrity of erythrocyte membrane
o G6PD deficiency may be the cause of hemolytic disease of newborn
o Drug-induced hemolytic anemia is most commonly associated with erythrocyte deficiency of G6PD.
o Deficiency is due to presence of G6PD enzyme that is present in young cells but rapidly disappears with cell aging.
o Disease is transmitted as an X-linked recessive.
o Full-expression occurs also in females who are homozygous for the gene; intermediate expression occurs in the heterozygous female carrier
o Fluorescent spot test is used to screen for G6PD deficiency
o NADPH produced in the reaction fluoresces under long-wave UV-light
o If there is a marked deficiency of G6PD or if this enzyme is lacking entirely, no fluorescence will be observed.
Samples for G6PD screening are usually cord blood for routine screening of newborn. The samples should always be received in EDTA tubes to prevent blood from clotting. Four types of control are used for this test; intermediate, blank, deficient and positive. The positive control is taken from the patient sample and is changed everyday. First, 100 microlitres of buffer is aliquoted into labeled tubes. This is followed by 5 microlitres of the patient’s blood. It is mixed left to incubate for 10 minutes. After the incubation, the samples are placed on filter paper and left to incubate for another 10 minutes. Over-incubating will cause false results; hence a timer must always be set. The filter paper is then read under the UV-light.
If the results are weak or negative, the test must be repeated and the sample must be checked for blood clots. If the blood is clotted, the nurse must be contacted to take a fresh sample of blood in an EDTA tube.
Urine FEME
o Kidneys maintain the internal environment by selectively excreting or retaining various substances accordingly to specific body needs
o They consist of a number of smaller functional units>>urinary tubules or nephrons
o Nephrons open to large collecting ducts, which open into a ureter.
o The two ureters run backward to open into a urinary bladder
o One of the main functions of the kidneys is the removal of waste products such as urea, uric acid, and creatinine from the body
o They also regulate volume and composition of body fluids and maintain correct osmolality, ion concentrations, and acid-base status of body
o First step in the production of urine is filtration of plasma passing through kidneys.
o Filtration occurs from glomerular capillaries into Bowman's capsule to form tubular fluid
o Glomerular filter prevents plasma proteins from passing into nephrons, but is permeable to all other plasma constituents (such as ions, glucose, amino acids, urea, etc)
o Thus filtration in the kidney is essentially non-selective — substances, which the body needs to retain, are filtered, as well as those substances, which need to be excreted.
o Urine analyzed to detect body disturbances>>endocrine or metabolic abnormalities, in which kidneys function normally but excrete abnormal amounts of abnormal amounts of metabolic end products specific for a particular disease.
o Analysis is also done to detect for intrinsic conditions that may adversely affect kidneys or urinary tract.
o Diseased kidneys cannot function normally in regulating volume and composition of body fluids, and in maintaining body homeostasis
o Consequently, substances normally retained by kidney or excreted in small amounts may appear in urine in large quantities, or substances normally excreted may be retained.
o Structural elementsàRBCs, WBCs, epithelial cells from urinary tract, and cast from diseased kidneys may appear in the urine
o Crystals, bacteria, yeast, protein, nitrite, glucose, ketone bodies, urobilinogen and bilirubin can also be found in the urine
o Different types of crystals:
§ pH<7 Amorphous nitrate
§ pH>or= 7 Amorphous phosphate
§ Calcium oxalate
§ Uric acid
§ Triple phosphates
§ Ammonium nitrate
§ Di-calcium phosphate
§ Calcium carbonateCalcium sulphate
Laboratory: Biochemistry
Neonatal serum bilirubin
o Breakdown of hemoglobin>>globin + heme
o Globin + iron >>re-utilized, leaving porphyrin portion of heme
o Breakdown of heme occurs in reticuloendothelial system
o Porphyrin ring opened up to form biliverdin
o Biliverdin>>reduced to bilirubin
o Bilirubin>>transported in plasma to liver>> conjugated with glucuronic acid
o Conjugated bilirubin>>further broken down in the intestines by intestinal bacteria>>urobilinogen
o Various reduction products of bilirubin may be absorbed from intestine>>returned to liver for re-excretion
o Any overload or blockage of this system raises levels of plasma total bilirubin
At least 80% of plasma bilirubin is unconjugated or indirect. When bilirubin in the blood is excessive, it deposits in the tissues, which causes jaundice. It may be caused by:
o Production of bilirubin more than the normal liver can excrete (e.g. hemolytic disease).
o Failure of the damaged liver to excrete the bilirubin produced in normal amounts (e.g. hepatitis).
o Obstruction of the excretory ducts in liver.
Neonatal physiological jaundice is common in newborns due to an immature fetal liver. The liver cannot conjugate all the bilirubin produced because of deficient enzymes. This jaundice however, disappears as the liver matures and enzymes function improves.
Upon receiving the patient samples, the samples are spun down so that the serum can be obtained for an accurate reading. The samples are that loaded into the REICHERT UNISTAT Bilirubinometer using a curvette. The readings are the recorded onto the request form and left to be verified.
G6PD screening test
o G6PD>>key enzyme in hexose monophosphate pathwayàrequired for formation of NADPH.
o NADPH>>essential for maintaining integrity of erythrocyte membrane
o G6PD deficiency may be the cause of hemolytic disease of newborn
o Drug-induced hemolytic anemia is most commonly associated with erythrocyte deficiency of G6PD.
o Deficiency is due to presence of G6PD enzyme that is present in young cells but rapidly disappears with cell aging.
o Disease is transmitted as an X-linked recessive.
o Full-expression occurs also in females who are homozygous for the gene; intermediate expression occurs in the heterozygous female carrier
o Fluorescent spot test is used to screen for G6PD deficiency
o NADPH produced in the reaction fluoresces under long-wave UV-light
o If there is a marked deficiency of G6PD or if this enzyme is lacking entirely, no fluorescence will be observed.
Samples for G6PD screening are usually cord blood for routine screening of newborn. The samples should always be received in EDTA tubes to prevent blood from clotting. Four types of control are used for this test; intermediate, blank, deficient and positive. The positive control is taken from the patient sample and is changed everyday. First, 100 microlitres of buffer is aliquoted into labeled tubes. This is followed by 5 microlitres of the patient’s blood. It is mixed left to incubate for 10 minutes. After the incubation, the samples are placed on filter paper and left to incubate for another 10 minutes. Over-incubating will cause false results; hence a timer must always be set. The filter paper is then read under the UV-light.
If the results are weak or negative, the test must be repeated and the sample must be checked for blood clots. If the blood is clotted, the nurse must be contacted to take a fresh sample of blood in an EDTA tube.
Urine FEME
o Kidneys maintain the internal environment by selectively excreting or retaining various substances accordingly to specific body needs
o They consist of a number of smaller functional units>>urinary tubules or nephrons
o Nephrons open to large collecting ducts, which open into a ureter.
o The two ureters run backward to open into a urinary bladder
o One of the main functions of the kidneys is the removal of waste products such as urea, uric acid, and creatinine from the body
o They also regulate volume and composition of body fluids and maintain correct osmolality, ion concentrations, and acid-base status of body
o First step in the production of urine is filtration of plasma passing through kidneys.
o Filtration occurs from glomerular capillaries into Bowman's capsule to form tubular fluid
o Glomerular filter prevents plasma proteins from passing into nephrons, but is permeable to all other plasma constituents (such as ions, glucose, amino acids, urea, etc)
o Thus filtration in the kidney is essentially non-selective — substances, which the body needs to retain, are filtered, as well as those substances, which need to be excreted.
o Urine analyzed to detect body disturbances>>endocrine or metabolic abnormalities, in which kidneys function normally but excrete abnormal amounts of abnormal amounts of metabolic end products specific for a particular disease.
o Analysis is also done to detect for intrinsic conditions that may adversely affect kidneys or urinary tract.
o Diseased kidneys cannot function normally in regulating volume and composition of body fluids, and in maintaining body homeostasis
o Consequently, substances normally retained by kidney or excreted in small amounts may appear in urine in large quantities, or substances normally excreted may be retained.
o Structural elementsàRBCs, WBCs, epithelial cells from urinary tract, and cast from diseased kidneys may appear in the urine
o Crystals, bacteria, yeast, protein, nitrite, glucose, ketone bodies, urobilinogen and bilirubin can also be found in the urine
o Different types of crystals:
§ pH<7 Amorphous nitrate
§ pH>or= 7 Amorphous phosphate
§ Calcium oxalate
§ Uric acid
§ Triple phosphates
§ Ammonium nitrate
§ Di-calcium phosphate
§ Calcium carbonateCalcium sulphate
Saturday, August 11, 2007
Haematology
Hello everyone! I've been attached to the haematology department for the past 7 weeks. There is 1 test that I'll like to share with you'll.
D-dimer Test (coagulation test)
The specific degradation of fibrin(i.e. fibrinolysis) is the mechanism responding to fibrin formation. Plasmin is the fibrinolytic enzyme that degrades fibrin into D-dimer. Hence, its appearance in the plama indicates that the fibrinolytic system is working in response to coagulation activation.
Coagulation Activation Plasmin
Fibrinogen -------------->Fibrin------------>D-dimer
D-dimers are crossed-linked degradation products of fibrin. D-Dimers are often associated with deep venous thrombosis(DVT), disseminated intravascular coagulation(DIC) and embolisms.
Hence, D-dimer can serve as a screening test for DVT.
Test Principle
D-Dimer test is a rapid latex agglutionation slide test that uses mouse monoclonal antibodies for semi-quantitative determination of D-dimer in the human plasma. The latex particles in the D-dimer reagent are coated with mouse anti-human D-dimer monoclonal antibodies. If the patient's plasma contains D-Dimes, it will cause agglutination when mixed with the latex particle suspension.
Test Procedure
1) The patient's plasma sample is checked against the name on the lab test request form.
-Neat Report-
2) 20uL of patient's plasma is pipetted into 1 circle on the black test card.
3) 20uL of D-dimer reagent is pipetted into the same circle on the test card.
4) The 2 drops on the test card are mixed using a mixing rod.
5) The test card is manually rotated for 2 mins in a manner such that the liquid swirls around the entire test circle.
6) When 2 min is up, check for agglutioination (i.e.bluish-white dots).
7) If no agglutination is observed, it is reported as D-dimer level<0.5ug/ml> -Semi Quantitative Determination-
1) 5 test circles are labelled as 1:2, 1:4, 1:8,1:16 and 1:32.
2) 20uL of D-dimer reagent is added to all the 5 test circles.
3) Similarly, 20ul of buffer is added to all the 5 test circles.
4) 20ul of patient's plasma is added to only the test circle labelled 1:2.
5) The patient's plasma is serially diluted with the buffer in the remaining test circles.
6) The reagent in the test circles are mixed using a mixing rod, in the following sequence, from 1:32 to 1:16 to 1:8 to 1:4 to 1:2.
7)The test card is manually rotated with 2 mins.
8) When 2 min is up, check for agglutination.
9) Plasma D-dimer levels are obtained by multiplying the dilution number by 0.5ug/ml. E.g. If 1:8 is the highest dilution that produces agglutination, the plasma D-dimer level=0.5ug/ml x8= 4ug/ml. Hence, plasma D-dimer level is reported as >4ug/ml.
Maybe this diagram cn help you'll to understand better..
Finally..That's the end of my post. Have fun reading it ahh.
Cheong Shu Hui
TG02
0503277F
D-dimer Test (coagulation test)
The specific degradation of fibrin(i.e. fibrinolysis) is the mechanism responding to fibrin formation. Plasmin is the fibrinolytic enzyme that degrades fibrin into D-dimer. Hence, its appearance in the plama indicates that the fibrinolytic system is working in response to coagulation activation.
Coagulation Activation Plasmin
Fibrinogen -------------->Fibrin------------>D-dimer
D-dimers are crossed-linked degradation products of fibrin. D-Dimers are often associated with deep venous thrombosis(DVT), disseminated intravascular coagulation(DIC) and embolisms.
Hence, D-dimer can serve as a screening test for DVT.
Test Principle
D-Dimer test is a rapid latex agglutionation slide test that uses mouse monoclonal antibodies for semi-quantitative determination of D-dimer in the human plasma. The latex particles in the D-dimer reagent are coated with mouse anti-human D-dimer monoclonal antibodies. If the patient's plasma contains D-Dimes, it will cause agglutination when mixed with the latex particle suspension.
Test Procedure
1) The patient's plasma sample is checked against the name on the lab test request form.
-Neat Report-
2) 20uL of patient's plasma is pipetted into 1 circle on the black test card.
3) 20uL of D-dimer reagent is pipetted into the same circle on the test card.
4) The 2 drops on the test card are mixed using a mixing rod.
5) The test card is manually rotated for 2 mins in a manner such that the liquid swirls around the entire test circle.
6) When 2 min is up, check for agglutioination (i.e.bluish-white dots).
7) If no agglutination is observed, it is reported as D-dimer level<0.5ug/ml>
If agglutination is observed, proceed to semi-quantitative determination of D-dimer using serial dilution.
1) 5 test circles are labelled as 1:2, 1:4, 1:8,1:16 and 1:32.
2) 20uL of D-dimer reagent is added to all the 5 test circles.
3) Similarly, 20ul of buffer is added to all the 5 test circles.
4) 20ul of patient's plasma is added to only the test circle labelled 1:2.
5) The patient's plasma is serially diluted with the buffer in the remaining test circles.
6) The reagent in the test circles are mixed using a mixing rod, in the following sequence, from 1:32 to 1:16 to 1:8 to 1:4 to 1:2.
7)The test card is manually rotated with 2 mins.
8) When 2 min is up, check for agglutination.
9) Plasma D-dimer levels are obtained by multiplying the dilution number by 0.5ug/ml. E.g. If 1:8 is the highest dilution that produces agglutination, the plasma D-dimer level=0.5ug/ml x8= 4ug/ml. Hence, plasma D-dimer level is reported as >4ug/ml.
Maybe this diagram cn help you'll to understand better..
Finally..That's the end of my post. Have fun reading it ahh.
Cheong Shu Hui
TG02
0503277F
Friday, August 10, 2007
(Sasi's) Q and A
Q1. Refer to Najib’s
Answer: The persistence of crystals in the urine can lead to inflammation of the mucus lining of the bladder and urethra. This can cause clinical signs identical to urinary tract infection, or the subsequent compromised state of the bladder mucosa lead to urinary infections. Chronic urinary crystals can also form bonds with one another, leading to the formation of stones within the bladder. Stone cause severe inflammation of urinary bladder, leading to blood in the urine, pain, and chronic infections. Kidney stones can obstruct the urinary passages and cause severe pain, and bleeding to the patient.Treatment of urinary crystals is accomplished through prescription diets that stablize the urine pH and eliminate dietary factors that lead to crystal formation. Small bladder stones can be treated by dissolution with the appropriate prescription diet like u had mentioned in your question. However, larger stones usually have to be removed surgically, and the patient has to placed on a good prescription diet to prevent their recurrence. Calcium oxylate stones cannot be dissolved with diet and have to be removed surgically. However, effective diets exist to prevent their recurrence. If the crystals do not pass out of the body naturally, the physician may use shock wave treatment. In this treatment, a shock wave focused on the stone from outside the body disintegrates it.
Q2. Refer to Dorene's
Answer:
Common Causes of Urine Discolouration
Brown:
Pathologic causes: Bile pigments,myoglobin
Food and drug causes: Levodopa, metronidazole, nitrofurantoin, some antimalarial agents
Brownish-black:
Pathologic causes: Bile pigments, melanin, methaemoglobin
Food and drug causes: Cascara, levodopa, methyldopa, senna
Green or blue:
Pathologic causes: Pseudomonal UTI, biliverdin
Food and drug causes: Amitriptyline, indigo carmine, IV cimetidine,IV promethazine, methylene blue, triamterene
Orange:
Pathologic causes: Bile pigments
Food and drug causes: Phenothiazines, phenazopyridine
Red:
Pathologic causes: Haematuria, aemoglobinuria, myoglobinuria, porphyria
Food and drug causes: Beets, blackberries, rhubarb Phenolphthalein, rifampicin
Yellow:
Pathologic causes: Concentrated urine (orange to gold in dehydration)
Food and drug causes: Carrots, Cascara
(fyi) Turbidity: Cloudy urine may be due to excess phosphate crystals precipitating in alkaline urine, which is of no clinical significance. However, it can also be seen in pyuria secondary to infection, chyluria (usually secondary to filariasis), hyperuricosuria secondary to a diet high in purine-rich foods, lipiduria and hyperoxaluria. Dorene, hope the above information would have cleared your doubts and also the part on Turbidity.
Q3. Refer to Lizzie's
Answer:
Whenever a Myco test is done, we compare the results to the positive control results. Yes, there is sure a chance for a false positive result to occur if the wells were subjected to agitation.
- Basically, a definite compact button in center of well with a smooth round outer margin indicates a negative result. A definite large ring with firmly agglutinated particles spread within the ring indicates a postive result.
- A specimen showing (-) with Unsensitized particles (at 1:20 final dilution) but demonstrating (+) or more with Sensitized particles (at 1:40 final dilution) is interpreted as positive. The end antibody titre is determined as the final dilution giving a (+) pattern.
- Regardless of the reading of the reaction pattern with Unsensitized particles, a specimen showing (-) with Sensitized Particles (at 1:40 dilution) is interpreted as negative.
Answer: The persistence of crystals in the urine can lead to inflammation of the mucus lining of the bladder and urethra. This can cause clinical signs identical to urinary tract infection, or the subsequent compromised state of the bladder mucosa lead to urinary infections. Chronic urinary crystals can also form bonds with one another, leading to the formation of stones within the bladder. Stone cause severe inflammation of urinary bladder, leading to blood in the urine, pain, and chronic infections. Kidney stones can obstruct the urinary passages and cause severe pain, and bleeding to the patient.Treatment of urinary crystals is accomplished through prescription diets that stablize the urine pH and eliminate dietary factors that lead to crystal formation. Small bladder stones can be treated by dissolution with the appropriate prescription diet like u had mentioned in your question. However, larger stones usually have to be removed surgically, and the patient has to placed on a good prescription diet to prevent their recurrence. Calcium oxylate stones cannot be dissolved with diet and have to be removed surgically. However, effective diets exist to prevent their recurrence. If the crystals do not pass out of the body naturally, the physician may use shock wave treatment. In this treatment, a shock wave focused on the stone from outside the body disintegrates it.
Q2. Refer to Dorene's
Answer:
Common Causes of Urine Discolouration
Brown:
Pathologic causes: Bile pigments,myoglobin
Food and drug causes: Levodopa, metronidazole, nitrofurantoin, some antimalarial agents
Brownish-black:
Pathologic causes: Bile pigments, melanin, methaemoglobin
Food and drug causes: Cascara, levodopa, methyldopa, senna
Green or blue:
Pathologic causes: Pseudomonal UTI, biliverdin
Food and drug causes: Amitriptyline, indigo carmine, IV cimetidine,IV promethazine, methylene blue, triamterene
Orange:
Pathologic causes: Bile pigments
Food and drug causes: Phenothiazines, phenazopyridine
Red:
Pathologic causes: Haematuria, aemoglobinuria, myoglobinuria, porphyria
Food and drug causes: Beets, blackberries, rhubarb Phenolphthalein, rifampicin
Yellow:
Pathologic causes: Concentrated urine (orange to gold in dehydration)
Food and drug causes: Carrots, Cascara
(fyi) Turbidity: Cloudy urine may be due to excess phosphate crystals precipitating in alkaline urine, which is of no clinical significance. However, it can also be seen in pyuria secondary to infection, chyluria (usually secondary to filariasis), hyperuricosuria secondary to a diet high in purine-rich foods, lipiduria and hyperoxaluria. Dorene, hope the above information would have cleared your doubts and also the part on Turbidity.
Q3. Refer to Lizzie's
Answer:
Whenever a Myco test is done, we compare the results to the positive control results. Yes, there is sure a chance for a false positive result to occur if the wells were subjected to agitation.
- Basically, a definite compact button in center of well with a smooth round outer margin indicates a negative result. A definite large ring with firmly agglutinated particles spread within the ring indicates a postive result.
- A specimen showing (-) with Unsensitized particles (at 1:20 final dilution) but demonstrating (+) or more with Sensitized particles (at 1:40 final dilution) is interpreted as positive. The end antibody titre is determined as the final dilution giving a (+) pattern.
- Regardless of the reading of the reaction pattern with Unsensitized particles, a specimen showing (-) with Sensitized Particles (at 1:40 dilution) is interpreted as negative.
Q4. Refer to Sally's
Answer:
hemolytic anemia is a disorder characterized by the premature destruction of red blood cells (rbcs) by the body's natural defenses against invading organisms. Hence, an elevated level of agglutinin will result in the premature destruction of rbcs. Normally, the red blood cells have a life span of approximately 120 days before they are destroyed by the spleen. In individuals with hemolytic anemia, the red blood cells are destroyed prematurely and the rate of production of new cells in the bone marrow can no longer compensate for their loss. The severity of the anemia is determined by the length of time that the red blood cells survive and by the rate at which the bone marrow continues to create new red blood cell production.
(fyi) The immune hemolytic anemias are classified according to the optimal temperature at which the antibodies act to destroy red blood cells. As their names imply, cold antibody hemolytic anemia occurs at temperatures of approximately 0 to 10 degree celsius (temperatures colder than normal body temperature), while warm antibody hemolytic anemia (WAHA) occurs at temperatures of 37 degrees celsius or higher.
Q5. Refer to Jia Hao's
Answer: There are two common types of hCG tests. A qualitative hCG test detects if hCG is present in the blood. A quantitative hCG test (or beta hCG) measures the amount of hCG actually present in the blood. First of all, you have to understand the purposes of both the tests. A qualitative hCG test is done via the commercial test strips to detect if a woman is pregnant in the first place. Quantitative hCG test is done to guage roughly how long has it been since the woman got pregnant.
In my experience at the lab, the manual testing method using the commercial strip is sensitive enough a method to see if the woman is pregnant. This is done at the Microbiolody Lab. On the other hand, at the Serology lab, we carry out the quantitative hCG test (or beta hCG) whichmeasures the amount of hCG actually present in the blood using the Immunolite Analyzer. For that, we do use the patients' serum for testing. This, like I mentioned, is used to roughly guage how long has the woman been pregnant.
(fyi) hCG levels during pregnancy:
hCG levels in weeks from LMP (gestational age) :
3 weeks LMP: 5 - 50 mIU/ml
4 weeks LMP: 5 - 426 mIU/ml
5 weeks LMP: 18 - 7,340 mIU/ml
6 weeks LMP: 1,080 - 56,500 mIU/ml
7 - 8 weeks LMP: 7, 650 - 229,000 mIU/ml
9 - 12 weeks LMP: 25,700 - 288,000 mIU/ml
13 - 16 weeks LMP: 13,300 - 254,000 mIU/ml
17 - 24 weeks LMP: 4,060 - 165,400 mIU/ml
25 - 40 weeks LMP: 3,640 - 117,000 mIU/ml
Non-pregnant females: <5.0>
- These numbers are just a guideline-- every woman’s level of hCG can rise differently. It is not necessarily the level that matters but rather the change in the level.
- In about 85% of normal pregnancies, the hCG level will double every 48 - 72 hours. As you get further along in pregnancy and the hCG level gets higher, the time it takes to double can increase to about every 96 hours.
- A single hCG reading is not enough information for most diagnoses. When there is a question regarding the health of the pregnancy, multiple testings of hCG done a couple of days apart give a more accurate assessment of the situation.
Q6. Refer to Vino's
Answer:
Upon the reasearch I have done, IgM type antibodies are stated as the most common type of cold agglutinin. However, there was this another antibody I came across named the Donath Landsteiner antibody. The Donath Landsteiner antibody is an IgG autoantibody that binds to red cells in the cold and fixes complement. Lysis occurs when cells are warmed to 37°C. Presence of the antibody is diagnostic for paroxysmal cold haemoglobinuria.
Specimen is collected into 2 plain tubes, one at 37°C and one at 4°C since cold agglutinins cause red blood cells to clump only at temperatures lower than 37 degree celsius. Supernatant serum examined for evidence of red cell lysis, comparing a tube incubated at 4°C then 37°C with a tube maintained at 37°C. No lysis in either tube indicates a negative result.
Q7. Refer to Royston's
Answer: Actually, as mentioned by my Lab personnel, controls not tallying is a rare occurrence as both the positive and negative controls are commercially prepared by manufacturers who have already run internal Qc for those controls before marketing them. However, in the event whereby the controls results do not tally with the previous day's, the controls will be run again. A different pair of positive and negative controls would be run this time. If despite that, the controls do not tally with the previous day's, the analyzer has to be calibrated again. Calibration refers to the process of determining the performance parameters of an artifact, instrument, or system by comparing it with measurement standards. Calibration assures that a device or system will produce results which meet or exceed some defined criteria with a specified degree of confidence. For example, my lab personnel from the microbiology lab mentioned that the photometer of the urine analyzer is blanked and restarted in the calibration process.
Hope Ive answered your questions. Feel free to clarify any more doubts of yours pertaining to my answers especially. Thank you once again for reading my posts! :)
Sasi
0503804g
Tg02
Monday, August 6, 2007
Cytogenetics
Unstimulated BM/ bone core/ leukaemic blood culture setup
Purpose: To establish haematopoietic cell cultures grown in culture flasks for cytogenetic analysis of haematological disorders.
BM is ideal specimen for chromosome studies in leukaemia. When BM aspirate is unsuccessful or is a dry tap, bone core or leukaemic blood may be used instead.
Blood may be taken in a sodium heparinized vacutainer .
Overnight culture set up (24- hour culture set up)
1.For marrow collected in sodium heparin vacutainer tube, pipette half the amount of BM aspirate into the Direct harvest Medium for direct harvest.
2.Obtain the recent FBC result from haematological lab and record in the BM culture worksheet.
3.Use the WBC as a guide to determine the number of drops of BM into the culture media.
4.Thaw one flask of complete RPMI 1640 culture media in a 37oC water bath for 20 mins
5.Place the specimen tube in bucket (a container to hold the tubes during centrifugation), screw tight the lid cover and centrifuge at 1500 rpm for 10 mins
6.Pipette the buffy coat out of specimen tube with a sterile 3 ml plastic transfer pipette into a sterile centrifuge tube.
**Buffy Coat > it is a layer of white cells which can be used to determine the cell lineage pathway
7.Sometimes, in order to assess the cellularity of the BM specimen (to determine the number of drops of buffy coat into the centrifuge tube). Smear and staining is also done and observes under the microscope (similar to our BBANK smear and stain). If there are more white cells we call it hyperplastic and low WBCs, we call it as hypoplastic. In case of hyperplastic, we only use ½ or 1 drop of the buffy coat ( > 1 drop will result in increased growth cells leading to insufficient space for growth). Hypoplastic BM, we will add about 3-4 drops.
8.After which, the buffy coat is then transferred to a RPMI 1640 culture media and placed in the CO2 incubator for overnight.
**For the steps are similar for 48-, 72- hour culture too. Interleukins are added before placing the culture flasks into the CO2 incubator.
LMQA
1.Safety of all lab staff is very important especially when handling the samples
2.It is also very important to maintain the temperature of refrigerator, incubator, freezer and other lab equipment as all these will have an effect on the sample.
3.All equipment is calibrated everyday early in the morning and is recorded. All QC forms are reviewed periodically by QC officer to ensure the equipment functions and perform according to specification
4.QC forms must be used for recording the performance check and maintenance on each piece of equipment
5.All documented QC forms are filled
Purpose: To establish haematopoietic cell cultures grown in culture flasks for cytogenetic analysis of haematological disorders.
BM is ideal specimen for chromosome studies in leukaemia. When BM aspirate is unsuccessful or is a dry tap, bone core or leukaemic blood may be used instead.
Blood may be taken in a sodium heparinized vacutainer .
Overnight culture set up (24- hour culture set up)
1.For marrow collected in sodium heparin vacutainer tube, pipette half the amount of BM aspirate into the Direct harvest Medium for direct harvest.
2.Obtain the recent FBC result from haematological lab and record in the BM culture worksheet.
3.Use the WBC as a guide to determine the number of drops of BM into the culture media.
4.Thaw one flask of complete RPMI 1640 culture media in a 37oC water bath for 20 mins
5.Place the specimen tube in bucket (a container to hold the tubes during centrifugation), screw tight the lid cover and centrifuge at 1500 rpm for 10 mins
6.Pipette the buffy coat out of specimen tube with a sterile 3 ml plastic transfer pipette into a sterile centrifuge tube.
**Buffy Coat > it is a layer of white cells which can be used to determine the cell lineage pathway
7.Sometimes, in order to assess the cellularity of the BM specimen (to determine the number of drops of buffy coat into the centrifuge tube). Smear and staining is also done and observes under the microscope (similar to our BBANK smear and stain). If there are more white cells we call it hyperplastic and low WBCs, we call it as hypoplastic. In case of hyperplastic, we only use ½ or 1 drop of the buffy coat ( > 1 drop will result in increased growth cells leading to insufficient space for growth). Hypoplastic BM, we will add about 3-4 drops.
8.After which, the buffy coat is then transferred to a RPMI 1640 culture media and placed in the CO2 incubator for overnight.
**For the steps are similar for 48-, 72- hour culture too. Interleukins are added before placing the culture flasks into the CO2 incubator.
LMQA
1.Safety of all lab staff is very important especially when handling the samples
2.It is also very important to maintain the temperature of refrigerator, incubator, freezer and other lab equipment as all these will have an effect on the sample.
3.All equipment is calibrated everyday early in the morning and is recorded. All QC forms are reviewed periodically by QC officer to ensure the equipment functions and perform according to specification
4.QC forms must be used for recording the performance check and maintenance on each piece of equipment
5.All documented QC forms are filled
Vinodhini
TGO2
Sunday, August 5, 2007
CYTOGENETICS ( BONE MARROW)
Hi Guys!!! This is already the sixth week of our attachment and here i am to tell you and share with you ppl abt my experience in CYTOGENETICS lab. Til today, i am enjoying myself working in this lab. There are three different stations in cytogenetics lab. One is prenatal (lab) where you will handle amniotic fluid samples, bone marrow (lab) where you will get to know more about haematological diseases and finally FISH which is actually aneuploidy screening of prenatal specimen. Currently i am under BM in short for bone marrow lab. I have lots to say but I will be covering the basics of cytogenetics, procedures, etc.
What is Cytogenetics?
Cytogenetics is the study of chromosome strucutre, pathology, function and behaviour. Chromsomes are best studied at mitotic or meiotic metaphase. Studies such as FISH methods may utilize interphase cells.
The type of sample and culture techniques used in our lab:
Basically we receive bone marrow, bone core and sometimes perpheral blood for chromosome analysis. We receive both local and regional samples. For local cases (the day you collect the bBM from the patient and the day you receive the sample is the same date) we have to perfom two different cultures. One is Direct Harvest and the other one is either one of these, 24-, 48-, 72- hour culture with or without mitogen (growth factors) depending on the diagnosis of the disease. As for Regional cases (if the date of collection of specimen is different from the date we receive is different) we can only set up only one or two (24-, 48-, 72- hour) cultures but not Direct Harvest. The reason for this will be explained shortly!
What is Direct Harvest and 24-, 48-, 72-hour culture??
Direct harvest: This is done to capture only spontaneously dividing cells (both abnormal and normal ones) upon arrival of the sample.
Culture: Cells are cultured for the study of non-spontaneouls dividing components or cells. The type of culture (whether it is 24-, 48-or 72- hour) depends on the diagnosis of the disease. E.g in my lab we usually perform 24-hour culture (also known as unstimulated culture due to the absence of mitogen = growth factor) for myeloid disorders one such example would be acute myeloid leukaemia (AML). As for lymphoid disorders, we will usually do a 48-hour culture with Interleukin-2 (which is actually a growth factor) and this is known as stimulated culture due to the addition of interleukin. One e.g. of lymphoid disorder would be Acute lymphoblastic leukaemia( ALL). As for 72-hour culture, we will usually do this for Myeloma cases (disease) as the cells will grow very slowly. Interleukin-6 is added for Myeloma cases. As you guys know the interleukins are produced in the body and these are required for certain abnormal clones or cells to grow (in the body itself). This is the reason why we add interleukins (to provide in vivo environment).
What i am trying to say is some abnormal cells or clones will grow under different conditions. Certain cells gorw very rapidly and this can be captured only in Direct Harvest culture. However, there are also cells that grow very slowly (1 to 3 days) and in order to capture these cells after you cultured them ( providing the in vivo environment for the cells to grow).
The procedures and the purpose of these procedures:
1) Harvesting: The first step in most harvest procedure is to arrest cells in the stage in which they must be in for standard cytogenetic analysis: Metaphase or prometaphase. In order to arrest cells under metaphase stage we have to add Colcemide. Colcemide will stop all the cells at metaphase stage for analysis. The effect of colcemid is to prevent spindle fiber formation, which would normally pull the sister chromatids to opposite poles for incorporation into two daughter cells. It also causes the chromosomes to condense, a process which is accentuated by increasing the time of exposure and concentration.
2) Hypotonic treatment: The second major step in harvesting is treament with a hypotonic saline solution to increase the cell volume so that the chromosome can find or have sufficient space to spread out ( to get beautiful metaphase to analysis) *i will try to get photos to show you ppl wat i mean by "beautiful metaphase"*
*Note: the above two solutions are prepared in our lab and both solutions can be found in one tube *
3) Fixation: The third constant feature of chromosome harvesting is the fixation of the cells. This process removes water from the cells and preserves them, hardening membranes and chromatin and in some way, preaparing the chromosome for banding (staining) procedure.
Fixative used: 3:1 methanol acetic acid. Fixative will cause the cells to be stronger ( harden the cell membrane). Cells are then kept in the fridge for slide making. During the fixative process, red cells present in the sample are also removed thus giving us a clear suspension. Basically fixation strengthens the cells and also gives a clear suspension for slide making. ( Fixation = washing of cells)
4) Slide Making: Once cells have been well fixed, they are then dropped onto glass slides and dried using specific condotions for optimal chromosome spreading and morphology.
**Theory of air drying: As the fixative evaporates, the layer of fixative becomes thinner and the meniscus pushes down on the top of the cell, enlarging the area of the cell and pressing the metaphase between the upper and lower membranes, spreading them out. We want the chromsomes to spread so that suring analysis we wont get chromsomes that are clumped together thus not allowing us to analyse them clearly.
After slide making, the slides are then stained using the Wrights and Giemsa stain. This is known as GTG banding. the G bands by trypsin using Giemsa and WRight's stain. Giemsa/Trypsin banding invloves the treatment with a proteolyitc enzymes trpysin and subsequent staining with a combination of Romanowsjy dye (Giemsa and Wright's stain). Dark bands generally replicate their DNA in late S phsase, contain A + T rich DNA, appear to contain relatively few active genes and differ from light ands in terms of protein composition. THe G bands by this technique allows the identification of individual chromosomes and structural rearrangements.
After staining, the slided are then covered with the coverslip (using DPX) and dried for about 30 mins and the slides are ready for microscopic analysis.
Guys there is more to tell you but i dun want to bombard you guys with so much of info.. I try to summarize as much as i can. So if there is anything u are not sure abt please feel free to ask me.. As for the photos i will try to put them up asap so that u will noe wat am trying to say about metaphase chromosomes etc etc.. Alrite?? And sorry if this is too long!!! I try to shorten but i couldn. I think i have to do another posting to tok about LMQA. I will do it asap ok! SOrry for the late posting too!!
Have great week ahead ppl!
Vinodhini
TGO2
0503171A
What is Cytogenetics?
Cytogenetics is the study of chromosome strucutre, pathology, function and behaviour. Chromsomes are best studied at mitotic or meiotic metaphase. Studies such as FISH methods may utilize interphase cells.
The type of sample and culture techniques used in our lab:
Basically we receive bone marrow, bone core and sometimes perpheral blood for chromosome analysis. We receive both local and regional samples. For local cases (the day you collect the bBM from the patient and the day you receive the sample is the same date) we have to perfom two different cultures. One is Direct Harvest and the other one is either one of these, 24-, 48-, 72- hour culture with or without mitogen (growth factors) depending on the diagnosis of the disease. As for Regional cases (if the date of collection of specimen is different from the date we receive is different) we can only set up only one or two (24-, 48-, 72- hour) cultures but not Direct Harvest. The reason for this will be explained shortly!
What is Direct Harvest and 24-, 48-, 72-hour culture??
Direct harvest: This is done to capture only spontaneously dividing cells (both abnormal and normal ones) upon arrival of the sample.
Culture: Cells are cultured for the study of non-spontaneouls dividing components or cells. The type of culture (whether it is 24-, 48-or 72- hour) depends on the diagnosis of the disease. E.g in my lab we usually perform 24-hour culture (also known as unstimulated culture due to the absence of mitogen = growth factor) for myeloid disorders one such example would be acute myeloid leukaemia (AML). As for lymphoid disorders, we will usually do a 48-hour culture with Interleukin-2 (which is actually a growth factor) and this is known as stimulated culture due to the addition of interleukin. One e.g. of lymphoid disorder would be Acute lymphoblastic leukaemia( ALL). As for 72-hour culture, we will usually do this for Myeloma cases (disease) as the cells will grow very slowly. Interleukin-6 is added for Myeloma cases. As you guys know the interleukins are produced in the body and these are required for certain abnormal clones or cells to grow (in the body itself). This is the reason why we add interleukins (to provide in vivo environment).
What i am trying to say is some abnormal cells or clones will grow under different conditions. Certain cells gorw very rapidly and this can be captured only in Direct Harvest culture. However, there are also cells that grow very slowly (1 to 3 days) and in order to capture these cells after you cultured them ( providing the in vivo environment for the cells to grow).
The procedures and the purpose of these procedures:
1) Harvesting: The first step in most harvest procedure is to arrest cells in the stage in which they must be in for standard cytogenetic analysis: Metaphase or prometaphase. In order to arrest cells under metaphase stage we have to add Colcemide. Colcemide will stop all the cells at metaphase stage for analysis. The effect of colcemid is to prevent spindle fiber formation, which would normally pull the sister chromatids to opposite poles for incorporation into two daughter cells. It also causes the chromosomes to condense, a process which is accentuated by increasing the time of exposure and concentration.
2) Hypotonic treatment: The second major step in harvesting is treament with a hypotonic saline solution to increase the cell volume so that the chromosome can find or have sufficient space to spread out ( to get beautiful metaphase to analysis) *i will try to get photos to show you ppl wat i mean by "beautiful metaphase"*
*Note: the above two solutions are prepared in our lab and both solutions can be found in one tube *
3) Fixation: The third constant feature of chromosome harvesting is the fixation of the cells. This process removes water from the cells and preserves them, hardening membranes and chromatin and in some way, preaparing the chromosome for banding (staining) procedure.
Fixative used: 3:1 methanol acetic acid. Fixative will cause the cells to be stronger ( harden the cell membrane). Cells are then kept in the fridge for slide making. During the fixative process, red cells present in the sample are also removed thus giving us a clear suspension. Basically fixation strengthens the cells and also gives a clear suspension for slide making. ( Fixation = washing of cells)
4) Slide Making: Once cells have been well fixed, they are then dropped onto glass slides and dried using specific condotions for optimal chromosome spreading and morphology.
**Theory of air drying: As the fixative evaporates, the layer of fixative becomes thinner and the meniscus pushes down on the top of the cell, enlarging the area of the cell and pressing the metaphase between the upper and lower membranes, spreading them out. We want the chromsomes to spread so that suring analysis we wont get chromsomes that are clumped together thus not allowing us to analyse them clearly.
After slide making, the slides are then stained using the Wrights and Giemsa stain. This is known as GTG banding. the G bands by trypsin using Giemsa and WRight's stain. Giemsa/Trypsin banding invloves the treatment with a proteolyitc enzymes trpysin and subsequent staining with a combination of Romanowsjy dye (Giemsa and Wright's stain). Dark bands generally replicate their DNA in late S phsase, contain A + T rich DNA, appear to contain relatively few active genes and differ from light ands in terms of protein composition. THe G bands by this technique allows the identification of individual chromosomes and structural rearrangements.
After staining, the slided are then covered with the coverslip (using DPX) and dried for about 30 mins and the slides are ready for microscopic analysis.
Guys there is more to tell you but i dun want to bombard you guys with so much of info.. I try to summarize as much as i can. So if there is anything u are not sure abt please feel free to ask me.. As for the photos i will try to put them up asap so that u will noe wat am trying to say about metaphase chromosomes etc etc.. Alrite?? And sorry if this is too long!!! I try to shorten but i couldn. I think i have to do another posting to tok about LMQA. I will do it asap ok! SOrry for the late posting too!!
Have great week ahead ppl!
Vinodhini
TGO2
0503171A
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