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   1. Objective The objective of the Complement Fixation Test (CFT) was to detect the presence of specific antibodies or antigens in a patient's serum by observing complement-mediated lysis of indicator red blood cells. 2. Principle The test was based on the ability of antigen–antibody complexes to fix complement. If the patient's serum contained specific antibodies, they formed a complex with the added antigen and fixed the complement. When sheep red blood cells (SRBCs) coated with anti-sheep RBC antibodies were added, no hemolysis occurred, indicating a  positive  result. If there were no antibodies, the complement remained free and lysed the indicator SRBCs, indicating a  negative  result. 3. Materials Used Patient serum (heat-inactivated) Known antigen Complement (usually guinea pig complement) Sheep red blood cells (SRBCs) Hemolysin (anti-sheep RBC antibodies) Controls (positive and negative) Incubator and water bath 4. Procedure The patient's serum wa...

   1. Objective The objective of this test was to evaluate the functionality of platelets by measuring their ability to aggregate in response to various agonists. 2. Principle The test was based on the principle that platelets, when exposed to aggregating agents (agonists), clump together. This aggregation caused a change in light transmission through platelet-rich plasma (PRP), which was measured by an aggregometer. A functional platelet population exhibited a characteristic response to each agonist. 3. Materials Used Patient’s citrated blood Centrifuge Platelet aggregometer Aggregating agents: ADP, collagen, epinephrine, arachidonic acid, ristocetin Cuvettes and stir bars Pipettes 4. Procedure Blood was collected in a citrate tube and centrifuged at low speed to obtain PRP. The remaining blood was centrifuged at higher speed to prepare platelet-poor plasma (PPP) for use as a blank. PRP was added into a cuvette with a magnetic stir bar and placed in the aggregometer. A known ...

  1. Objective The objective of the test was to detect the presence of Vibrio cholerae, the bacterium responsible for cholera, in stool samples or rectal swabs, aiding in diagnosis and outbreak control. 2. Principle The test was based on isolating and identifying Vibrio cholerae using culture, microscopy, or rapid immunochromatographic test kits. Culture allowed confirmation, while rapid tests gave quicker preliminary results by detecting cholera antigen in stool. 3. Materials Depending on the method used: ✔ For Culture: • Fresh stool sample or rectal swab • Transport media (Cary-Blair) • Selective media (Thiosulfate Citrate Bile Salts Sucrose agar – TCBS) • Enrichment broth (Alkaline Peptone Water) • Microscope and staining reagents • Oxidase reagent • Biochemical test kits ✔ For Rapid Cholera Dipstick Test: • Stool sample • Cholera antigen rapid test cassette • Extraction buffer • Dropper • Timer Read more test 4. Procedure 🧪 A. Culture Method 1. Stool ...

   1. Objective The objective of this test was to detect the presence of HIV (Human Immunodeficiency Virus) antibodies or antigens in a patient's blood or serum to screen for HIV infection. 2. Principle The test was based on the detection of HIV-specific antibodies (IgG, IgM) and/or p24 antigen using Enzyme-Linked Immunosorbent Assay (ELISA), Rapid Immunochromatographic Tests, or Western Blot. In some advanced cases, nucleic acid testing (NAT) was used for early detection. 3. Materials Used HIV Rapid Test Kit (e.g., Determine, Uni-Gold, First Response) Patient's blood or serum sample Buffer solution Micropipette and tips Timer Biohazard disposal 4. Procedure A drop of patient’s whole blood or serum was placed on the test device sample pad. Two drops of buffer solution were added. The sample was allowed to migrate across the test strip by capillary action. Results were read after 15–20 minutes. Control and test lines were observed to interpret the result. 5. Result Positive: ...

   1. Objective The objective of the experiment was to count and analyze different types of cells in a given sample using flow cytometry based on light scatter and fluorescence properties. 2. Principle Flow cytometry was used to count and characterize cells as they passed individually through a laser beam. Cells were differentiated by their size (forward scatter), internal complexity (side scatter), and fluorescence intensity if stained with specific markers. Counting was achieved using volumetric analysis or by adding a known number of fluorescent counting beads. 3. Materials Used Flow cytometer (e.g., BD FACSCanto) Cell suspension (e.g., peripheral blood, cultured cells) Fluorescently labeled antibodies (e.g., CD45, CD3) Counting beads (optional) PBS (phosphate-buffered saline) FACS tubes Vortex mixer and pipettes 4. Procedure The cell suspension was prepared and filtered to remove clumps. Fluorescent antibodies were added to label specific cell populations. The samples were...

   1. Objective: To detect and identify unexpected antibodies in a patient’s serum that may react with red blood cell antigens, especially before transfusion. 2. Principle: Patient serum is mixed with reagent red cells of known antigen profiles. Agglutination indicates the presence of antibodies. Identification involves comparing reaction patterns with known antigen matrices. 3. Materials: Patient serum/plasma Screening and identification red cell panels LISS or saline Antiglobulin reagent (Coombs reagent) Test tubes or gel cards Centrifuge, incubator 4. Procedure: Mix patient serum with screening cells → incubate. Wash to remove unbound antibodies. Add antihuman globulin → check for agglutination. If positive, proceed to identification with an extended red cell panel. Compare agglutination pattern to known antigen profiles. 5. Result Interpretation: No agglutination : No detectable antibodies. Agglutination with specific cells : Suggests presence of particular antibody (e.g.,...