EAGLES EYE UPDATE

When working with Gram-positive bacteria in a laboratory setting, culture media plays a crucial role in their identification and study. Here's how Gram-positive bacteria interact with different types of culture media: General Principles: Nutrient Requirements :    * Like all bacteria, Gram-positive organisms need specific nutrients to grow. Culture media provides these essential elements, including carbon sources, nitrogen sources, vitamins, and minerals. Selective vs. Differential Media:    * Culture media can be either selective, differential, or both.    * Selective media inhibits the growth of certain bacteria while allowing others to grow. This is useful for isolating specific Gram-positive species from a mixed population.    * Differential media contains substances that allow different bacteria to be distinguished based on their metabolic reactions. This helps in identifying specific species. Examples of Culture Media and Gram-Po...

1. Eyepiece (Ocular lens) Located at the top of the microscope. Magnifies the image (usually 10× or 15×). The lens through which you look. 2. Objective lenses Attached to a rotating nosepiece. Provide different magnifications (commonly 4×, 10×, 40×, 100× oil immersion). Work with the eyepiece to enlarge the specimen. 3. Nosepiece (Revolving turret) Holds the objective lenses. Rotated to switch between magnifications. 4. Stage Flat platform where the slide is placed. Has stage clips or a mechanical stage to hold the slide steady. 5. Stage clips / Mechanical stage Keep the glass slide in position. The mechanical stage allows precise slide movement. 6. Condenser Located under the stage. Focuses and directs light onto the specimen for clarity. 7. Diaphragm (Iris diaphragm) Controls the amount of light passing through the condenser. Adjusts brightness and contrast. 8. Light source / Mirror Provides illumination (built-in lamp in modern microscopes, mirror in older types). Essent...

1. Objective To measure the glucose level in the blood at any random time of the day, regardless of the last meal, for screening and monitoring diabetes mellitus. 2. Principle The RBS test was based on the glucose oxidase-peroxidase (GOD-POD) method. Glucose in the sample was oxidized by glucose oxidase to gluconic acid and hydrogen peroxide. Hydrogen peroxide then reacted with a chromogen in the presence of peroxidase, producing a color change. The intensity of the color was proportional to the glucose concentration and was measured spectrophotometrically. 3. Materials Patient’s blood sample (capillary or venous) Glucometer with test strips (for bedside test) or spectrophotometer (for lab test) Glucose oxidase reagent kit Test tubes, pipettes 4. Procedure Bedside (Glucometer): 1. A finger prick was performed using a sterile lancet. 2. A drop of blood was placed on the glucose test strip. 3. The glucometer displayed the blood glucose concentration. Laboratory (GOD-POD meth...

1. Objective To assess kidney function and electrolyte balance by measuring sodium (Na⁺), potassium (K⁺), chloride (Cl⁻), urea, and creatinine in blood. 2. Principle Electrolytes (Na⁺, K⁺, Cl⁻) : Measured using ion-selective electrodes (ISE) that detect specific ions. Urea : Measured by the urease method, where urea is hydrolyzed to ammonia, which is then quantified. Creatinine : Commonly measured by the Jaffe’s reaction, where creatinine reacts with picric acid in alkaline solution to form a colored complex. 3. Materials Patient blood sample (serum or plasma) Centrifuge Ion-selective electrode analyzer Urea reagent (urease) Creatinine reagent (Jaffe’s solution) Test tubes, pipettes 4. Procedure (Laboratory) 1. Blood was collected and centrifuged to obtain serum. 2. Serum was analyzed for: Electrolytes using ion-selective electrode analyzer. Urea by enzymatic method. Creatinine by Jaffe’s method. 3. Results were compared to standard reference ranges. 5. Results (Normal Rang...

1. Objective The objective of the AFP test was to measure the level of alpha-fetoprotein in the blood to help detect certain liver diseases, cancers, and fetal abnormalities during pregnancy. 2. Principle The principle was based on immunoassay methods. AFP in the serum bound to specific antibodies, and the antigen–antibody reaction was measured quantitatively using enzyme-linked immunosorbent assay (ELISA), chemiluminescence, or other immunoassay techniques. 3. Materials Patient’s blood sample (serum) Collection tubes and centrifuge ELISA kit or automated immunoassay analyzer Reagents: coated microplates, conjugated antibodies, substrate solution, stop solution Micropipettes and tips 4. Procedure (ELISA method ) 1. Blood sample was collected and centrifuged to obtain serum. 2. Serum was added to microplate wells coated with anti-AFP antibodies. 3. After incubation, wells were washed to remove unbound substances. 4. Enzyme-conjugated secondary antibody was added, binding to ...

Great analogy! Let’s use the relationship between husband and wife to explain antigen–antibody reaction in a simple way: 1. Antigen as the Husband (the stranger/problem-maker) The antigen is like a husband coming into the home with unique behaviors, features, or habits. He is foreign to the wife at first (like how antigens are foreign to the immune system). Each husband has unique qualities (just like antigens have specific structures called epitopes). 2. Antibody as the Wife (the recognizer/responder) The antibody is like the wife, who is able to recognize and bind specifically to her husband. Just as a wife is "designed" to know her husband uniquely, an antibody is highly specific to its antigen. She won’t confuse another man for her husband, the way antibodies don’t usually bind to unrelated antigens. 3. Specific Binding (Marriage Bond) The way the wife attaches herself emotionally and socially to her husband is like the lock-and-key fit between antigen and an...

Sperm malformation (also called teratozoospermia) means that a man’s sperm cells have abnormal shapes or structures. Normally, sperm should have an oval head, intact midpiece, and a long straight tail that allows it to swim effectively. When sperm are malformed, fertility can be reduced because they may not be able to swim properly or fertilize an egg. Types of sperm malformations Head abnormalities Large head / Small head – irregular size makes it difficult to penetrate the egg. Double head  – two heads attached, usually non-functional. Pinhead sperm – head too small, often lacking genetic material. Round head (globozoospermia ) – head lacks acrosome, so sperm cannot break into the egg. Amorphous head – irregular, misshaped head. Vacuoled head – head has empty spaces, affecting DNA quality. Midpiece abnormalities Thickened midpiece – may contain excess cytoplasm. Bent midpiece  – affects motility. Irregular mitochondria distribution * – lowers energy supply....

1. Objective The objective of the HbA1c test was to measure the average blood glucose concentration over the previous two to three months by detecting the proportion of glycated hemoglobin in a blood sample. This evaluation provided long-term glycemic control status for diabetic patients. 2. Principle The test was based on the principle that glucose in the bloodstream bound irreversibly to hemoglobin within red blood cells, forming glycosylated hemoglobin (HbA1c). Since red blood cells had an average lifespan of 120 days, the amount of HbA1c reflected the average blood glucose concentration over that period. Various analytical methods such as ion-exchange chromatography, immunoassay, or high-performance liquid chromatography (HPLC) were used to separate and quantify HbA1c. 3. Materials The materials that were used included: • Sterile syringes and vacutainer tubes (with EDTA anticoagulant) for blood collection • Microscopic slides and cover slips • Stains (as required for mi...

1. Objective The objective of the RVS test was to study the microscopic details of cells/tissues by using specific stains. The test aimed to enhance the contrast between different cellular components, making microscopic examination clearer and more informative. 2. Principle The principle of the test was based on the selective uptake of stains by various cell structures. Acidic dyes stained basic components (like cytoplasm), while basic dyes stained acidic components (like nucleus). This differential staining allowed the observer to distinguish between different parts of the cell under the microscope. 3. Materials The materials that were used included: • Prepared tissue or cell samples (smears/sections) • Microscope slides and cover slips • Stains (e.g., Hematoxylin, Eosin, Safranin, or specific dyes depending on sample) • Distilled water • Droppers and staining rack • Microscope 4. Procedure (Microscopic) 1. The specimen was fixed onto a clean glass slide. 2. The fixed samp...

1. Objective To assess kidney function by measuring levels of waste products and electrolytes in the blood, such as urea, creatinine, and uric acid. 2. Principle The test measures substances that are normally filtered by the kidneys. Elevated or decreased levels indicate impaired renal function. 3. Materials Patient’s blood sample (serum) Test tubes Centrifuge Biochemical analyzer Reagents for urea, creatinine, uric acid, electrolytes 4. Procedure 1. Collect venous blood sample. 2. Centrifuge to separate serum. 3. Load serum into the biochemical analyzer. 4. Add specific reagents for urea, creatinine, and uric acid estimation. 5. Analyzer provides quantitative results. 5. Result :   Normal Range Urea 32 mg/dL 10–40 mg/dL Creatinine 1.0 mg/dL 0.7–1.3 mg/dL Uric Acid 4.5 mg/dL 3.5–7.2 mg/dL Sodium 139 mmol/L 135–145 mmol/L Potassium 4.1 mmol/L 3.5–5.0 mmol/L 6. Uses Diagnosis of kidney diseases Monitoring patients with hypertension or diabetes Assessing renal damage in dr...

1. Objective The objective of the Complete Blood Count (CBC) test was to evaluate the overall health and detect a variety of disorders, such as anemia, infection, inflammation, and blood cancers, by measuring different components of blood. 2. Principle The test was based on the automated or manual quantification of blood cells (RBCs, WBCs, platelets) and the measurement of hemoglobin, hematocrit, and red cell indices using electrical impedance, light scattering, or microscopy. 3. Materials EDTA-anticoagulated whole blood sample Automated hematology analyzer Microscope (for manual differential) Hemocytometer (if manual counting required) Glass slides, cover slips, Wright’s or Giemsa stain Gloves and PPE 4. Procedure (Automated method) 1. A venous blood sample was collected in an EDTA tube. 2. The sample was loaded into the hematology analyzer. 3. The analyzer performed measurements using methods like impedance and flow cytometry. 4. A peripheral blood smear was prepared and ...

In microbiology, simple biochemical tests can instantly separate major groups of bacteria: Catalase Test Principle : Detects the enzyme catalase, which breaks down hydrogen peroxide (H202 -> H20 + 02). Positive result : Bubbling (oxygen release). Example : Staphylococcus spp. (positive) vs Streptococcus spp. X (negative)  Oxidase Test Principle : Detects cytochrome c oxidase enzyme in the bacterial electron transport chain. Positive result : Purple/blue color within seconds. Example: Pseudomonas, Neisseria (positive) vs  Enterobacteriaceae X (negative). Why it matters ? These tests are : . Rapid (results in seconds to minutes) • Useful for preliminary bacterial differentiation  Essential in clinical and diagnostic labs for quick decision-making. A single drop of reagent can guide the path toward correct identification & treatment

Please 🙏, at our various duty posts, let us be safety conscious. - Ensure the use of face masks 😷. - Use hand gloves regularly.  - Regular hand washing  - Keep social distance  - Fumigate your work area.  - Regular insecticide can help.  You will observe the rate at which labs are recording MP+ in the last couple of weeks. Vectors such as mosquitoes can cause diseases like dengue, chikungunya and malaria at home or when travelling. Take these simple measures to protect yourself and your family. 

1. Objective : The objective of the HIV test was to detect antibodies, antigens, or nucleic acids of the Human Immunodeficiency Virus in order to diagnose HIV infection and monitor its stage. 2. Principle : The principle of HIV testing varied depending on the method: ELISA (Enzyme-Linked Immunosorbent Assay ): It was based on the antigen-antibody reaction where HIV antigens coated on a microplate captured patient antibodies (if present), and a color change indicated positivity. Rapid Test (ICT – Immunochromatographic Test ): It relied on antigen-antibody binding producing a visible colored line on a strip. Western Blot : It detected specific HIV proteins using patient antibodies as confirmation. PCR (Polymerase Chain Reaction ): It detected HIV RNA/DNA in blood, useful in early infection or newborns. 3. Materials : Patient’s serum or plasma sample HIV test kit (ELISA plate / Rapid strip / PCR reagents) Micropipettes and tips Buffer solution ELISA reader (for ELISA method) C...

1. Objective The objective of the test was to determine the total iron-binding capacity of serum, which reflected the ability of transferrin to bind iron. 2. Principle The principle of the test was based on the fact that transferrin in serum bound iron. Excess iron was added to saturate all binding sites, and the unbound iron was removed. The concentration of iron that remained bound to transferrin was then measured. This value represented the total iron-binding capacity. 3. Materials The materials used were: • Patient serum sample • Iron reagent solution (ferric chloride or ferrous ammonium sulfate) • Buffer solution • Precipitating reagent to remove unbound iron • Color reagent (such as bathophenanthroline or ferrozine) • Spectrophotometer • Test tubes, pipettes, and centrifuge 4. Procedure (Microscopic/Analytical Steps) 1. Serum was collected from the patient. 2. Excess iron reagent was added to the serum to saturate transferrin binding sites. 3. A precipitating reagent ...

1. Objective The objective of the test was to measure the rate at which red blood cells settled at the bottom of a vertical tube over a specified period, helping to detect inflammation in the body. 2. Principle The test was based on the principle that red blood cells settle faster in the presence of increased plasma proteins, such as fibrinogen and immunoglobulins, which occur during inflammation. The distance the RBCs fell in a given time was measured and expressed in millimeters per hour (mm/hr). 3. Materials • Patient’s blood sample (mixed with anticoagulant) • Westergren or Wintrobe ESR tube • Anticoagulant (sodium citrate) • ESR stand • Timer • PPE (gloves, lab coat) 4. Procedure (Microscopic/Analytical) 1. Blood was collected by venipuncture and mixed with sodium citrate anticoagulant in a 4:1 ratio. 2. The mixture was drawn into a Westergren tube up to the zero mark. 3. The tube was placed vertically in an ESR stand. 4. The level of clear plasma at the top of the col...