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USE of high-energy radiation such as gamma RAYS to sterilize an ARTICLE.

Use of high-energy radiation such as gamma rays to sterilize an article.

By FUMIGATION with FORMALDEHYDE.

By fumigation with formaldehyde.

It DISINFECTS and solidifies EGG and serum containing MEDIA such as U MEDIUM and LoelTiers serum slope.

It disinfects and solidifies egg and serum containing media such as U medium and LoelTiers serum slope.

PORCELAIN filters. Seitz (asbestos) filters. Sintered glass filters. MEMBRANE filters and HEP filters.

Porcelain filters. Seitz (asbestos) filters. Sintered glass filters. Membrane filters and HEP filters.

Ducking Is a process of INACTIVATION of Anthrax spores in animal products such as wool, HAIRS or bristles. It was INTRODUCED by Elmhirst Duckering, an enginer at wool factory. This is a live-step process. each lasting for 10 minutes and carried out at 40.5°c.

• immersion in 0.25-0.3% alkali
• immersion in SOAPY water
• immersion in 2% formaldehyde
• secondimmersion in 2% formaldehyde
• rinsinq in water

Ducking Is a process of inactivation of Anthrax spores in animal products such as wool, hairs or bristles. It was introduced by Elmhirst Duckering, an enginer at wool factory. This is a live-step process. each lasting for 10 minutes and carried out at 40.5°c.

Alkylation (hydrogen ATOM is replaced with an alkyl group) of protein. DNA. and RNA afFects bacterial metabolism and replication. EQ gas (8.5%) is often MIXED with stabilizers such as CO2 (91 5%) or HYDROCHLOROFLUOROCARBONS (HCFC). This requires high humidity (40-80%) and long exposure times (1-6 HRS).

Alkylation (hydrogen atom is replaced with an alkyl group) of protein. DNA. and RNA afFects bacterial metabolism and replication. EQ gas (8.5%) is often mixed with stabilizers such as CO2 (91 5%) or hydrochlorofluorocarbons (HCFC). This requires high humidity (40-80%) and long exposure times (1-6 hrs).

Glutaraldehyde or a COMBINATION of peracetic ACID and hydrogen peroxide can be used.

Glutaraldehyde or a combination of peracetic acid and hydrogen peroxide can be used.

GAMMA RAYS. ELECTRON beams and ETHYLENE oxide

Gamma rays. Electron beams and Ethylene oxide

By TREATING them with DISINFECTANT, BOILING or AUTOCLAVING and finally by incineration

By treating them with disinfectant, boiling or autoclaving and finally by incineration

SODIUM HYPOCHLORITE or CALCIUM hypochlorite

Sodium hypochlorite or Calcium hypochlorite

• Tincture Iodine - 2% of Iodine in 70% alcohol - lodophore - Povidone Iodine.
• NAME some antiseptics.
• Chlorhexidine. CHLOROXYLENOL. SPIRIT (70% alcohol), tincture of Iodine. H202.

These are the chemicals used for STERILIZATION. They are 2% Gluteraldehyde (cidex). ETHYLENE OXIDE (EO). Formaldehyde + steam and Beta — Propiolactone (BPL).

These are the chemicals used for sterilization. They are 2% Gluteraldehyde (cidex). Ethylene Oxide (EO). Formaldehyde + steam and Beta — Propiolactone (BPL).

The active ingredients include Chlorhexidine. TRICLOSAN. Thymol. Cetylpyridinium CHLORIDE, and ALCOHOL. The COMPOSITION varies across BRANDS.

The active ingredients include Chlorhexidine. Triclosan. Thymol. Cetylpyridinium Chloride, and alcohol. The composition varies across brands.

The active INGREDIENT of Dettol is CHLOROXYLENOL whereas Savlon contains a COMBINATION of Cetrimide and Chiorhexidine.

The active ingredient of Dettol is chloroxylenol whereas Savlon contains a combination of Cetrimide and Chiorhexidine.

Quaternary ammonium COMPOUNDS are positively charged POLYATOMIC ions, which CONCENTRATE at the CELL surface and ALTER the physical and chemical properties of the membrane, thus killing the cefl. Examples inlcude Benzalkonium chloride and Cetrimonium bromide.

Quaternary ammonium compounds are positively charged polyatomic ions, which concentrate at the cell surface and alter the physical and chemical properties of the membrane, thus killing the cefl. Examples inlcude Benzalkonium chloride and Cetrimonium bromide.

Antiseptics are MILD disinfectants that can be SAFELY USED on SKIN and mucous membranes.

Antiseptics are mild disinfectants that can be safely used on skin and mucous membranes.

PHENOL. LYSOL, FORMALDEHYDE. SODIUM HYPOCHLORITE.

Phenol. Lysol, Formaldehyde. Sodium hypochlorite.

By HIGH Elliciency PARTICULATE AIR (HEPA) FILTERS.

By High Elliciency Particulate Air (HEPA) filters.

By FILTRATION.

By filtration.

CULTURE MEDIA, GLOVES. COTTON and CLOTHES.

Culture media, gloVes. cotton and clothes.

GLASSWARE’s, metallic instruments LIKE scissors and forceps, swabs. POWDER. OILS and GREASE.

Glassware’s, metallic instruments like scissors and forceps, swabs. powder. oils and grease.

121°C for 15 minutes at 15 POUNDS per SQUARE inch of pressure

121°C for 15 minutes at 15 pounds per square inch of pressure

160°C for 60 MINUTES

160°C for 60 mInutes

The process of kdling all HYING forms including spores is called STERILIZATION and the process of killing of only the vegetative form of pathogenic BACTERIA as WELL as other microbes is DISINFECTION

The process of kdling all hying forms including spores is called sterilization and the process of killing of only the vegetative form of pathogenic bacteria as well as other microbes is disinfection

SOLUTION A(1) contains Toluidine BLUE, Malachite GREEN, Glacial acetic acid and Alcohol while solution 8(2) contains iodine and POTASSIUM iodide In distilled WATER.

Solution A(1) contains Toluidine blue, Malachite green, Glacial acetic acid and Alcohol while solution 8(2) contains iodine and potassium iodide In distilled water.

The bacdh are ARRANGED at angles to each other resembling ENGLISH letter V or L or CHINESE letter (cuneiform) pattern because the daughter cells doWt separate completely after CELL dMslon (binary rission).

The bacdh are arranged at angles to each other resembling English letter V or L or Chinese letter (cuneiform) pattern because the daughter cells doWt separate completely after cell dMslon (binary rission).

ALBERT’s stain. Neissers stain, Ponder’s stain and Pugh’s stain They can be demonstrated as retractile BODIES in wet MOUNT or SLIGHTLY more gram positive structures in Gram stain.

Albert’s stain. Neissers stain, Ponder’s stain and Pugh’s stain They can be demonstrated as retractile bodies in wet mount or slightly more gram positive structures in Gram stain.

Metachromatic granules are pol’ymetaphosphate reserves produced by Corynebacterium DIPHTHERIAE in nutritious medium. These granules are ALSO KNOWN as Babes Ernst granules. ‘blutin granules. Polar BODIES etc. They are called metachromatic granules because of they exhibit metachromasia.

a property where the granules appear in a colour different from that of the dye used When stained with polychrome methylene blue, they appear purple They are produced In ABUNDANCE In serum containing medium such as Loeffler’s serum slope.

Metachromatic granules are pol’ymetaphosphate reserves produced by Corynebacterium diphtheriae in nutritious medium. These granules are also known as Babes Ernst granules. ‘blutin granules. Polar bodies etc. They are called metachromatic granules because of they exhibit metachromasia.

a property where the granules appear in a colour different from that of the dye used When stained with polychrome methylene blue, they appear purple They are produced In abundance In serum containing medium such as Loeffler’s serum slope.

BEADED appearance is used to DESCRIBE the appearance of Mycobacterla when the cell doesn’t stain UNIFORMLY. showing stained and unstained regions. These forms are common in Mycobacterium tuberculosis while Mycobacterium bovis STAINS uniformly. Most saprophytic MYCOBACTERIA stain uniformly.

Beaded appearance is used to describe the appearance of Mycobacterla when the cell doesn’t stain uniformly. showing stained and unstained regions. These forms are common in Mycobacterium tuberculosis while Mycobacterium bovis stains uniformly. Most saprophytic Mycobacteria stain uniformly.

Sputum smears for Mycobacterla can be stained by fluorescent dyes such as Auramine and Rhodamlne as they have AFFINITY for mycolic ACID In their CELL walIs The fluorescent microscopy is useful in screening large number of specimens. Large AREA of smear can be quickly observed that too under high power dry objective.

Sputum smears for Mycobacterla can be stained by fluorescent dyes such as Auramine and Rhodamlne as they have affinity for mycolic acid In their cell walIs The fluorescent microscopy is useful in screening large number of specimens. Large area of smear can be quickly observed that too under high power dry objective.

Smears are graded depending on the number of bacilli SEEN

• 3-9 bacilli/entire smear: +
• 10 bacilli/entire smear ++
• 10 bacilli/in most OIL Immersion FIELDS: +++

Smears are graded depending on the number of bacilli seen

At LEAST 100 oIl Immersion fields must be viewed before declaring the smear as negative The sensitivity of smear Is LOW because It requires the presence of 104 bacillilml to be smear positive. If the number of bacilli is less than this, the chances of detecting them are less In such a case, the sample should be SUBJECTED to concentration techniques such as Petroff s method If the smear Es positive for AFB. it should be counted/graded Failure to DETECT any AFB does not RULE tuberculosis Grading of smears has prognostic value.

At least 100 oIl Immersion fields must be viewed before declaring the smear as negative The sensitivity of smear Is low because It requires the presence of 104 bacillilml to be smear positive. If the number of bacilli is less than this, the chances of detecting them are less In such a case, the sample should be subjected to concentration techniques such as Petroff s method If the smear Es positive for AFB. it should be counted/graded Failure to detect any AFB does not rule tuberculosis Grading of smears has prognostic value.

• A new SLIDE must be used for every specimen. because scratch MARKS may GIVE false positive.
• A uniform smear from thick portion of the sputum must be made.
• Staining jars should not be used to staining smear as there is risk to cross CONTAMINATION
• Fresh blotting PAPER must be used for each smear for drying the slide to prevent transfer from one slide to another.

For UNIFORM distribution of HEAT, or else the SLIDE MAY BREAK.

For uniform distribution of heat, or else the slide may break.

The two methods namely Kinyoun’s and Gabbetts dont involve heating of SLIDES, hence called cold methods. Heating is substituted by increased concentration of phenol and prolonging the duration of staining. Kinyoun’s METHOD is favoured for DETECTION of Cryptosporidium oocysts in fecal samples. Gabbetts method has decolourizer and counterstain in one SOLUTION.

The two methods namely Kinyoun’s and Gabbetts dont involve heating of slides, hence called cold methods. Heating is substituted by increased concentration of phenol and prolonging the duration of staining. Kinyoun’s method is favoured for detection of Cryptosporidium oocysts in fecal samples. Gabbetts method has decolourizer and counterstain in one solution.

• Mycobacterlum leprae - 5% H2S04
• Oocysts of Cryptosporidium. Isospora - 1 % H2S04
• Tissue sections CONTAINING Actinomyctes. NOCARDIA - 1 % H2S04
• Cultures of Nocardia - 0.5% H2S04
• BACTERIAL SPORES - 0.25-0.5% H2S04

3% HCI in 95% alcohol (methylated spirit). This is useful in dilrerentiating saprophytic Mycobacteria from pathogenic Mycobacteria Pathogenic Mycobacteria are both acid and alcohol fast but saprophytic Mycobacterla are only acid-fast Saprophytic Mycobacterla can get declourized by alcohol. 95% alcohol can be USED as a secondary decolorizer after decolourizing with acid Especially used in staining smears prepared from URINE that may CONTAIN Mycobacterium smegmatis.

3% HCI in 95% alcohol (methylated spirit). This is useful in dilrerentiating saprophytic Mycobacteria from pathogenic Mycobacteria Pathogenic Mycobacteria are both acid and alcohol fast but saprophytic Mycobacterla are only acid-fast Saprophytic Mycobacterla can get declourized by alcohol. 95% alcohol can be used as a secondary decolorizer after decolourizing with acid Especially used in staining smears prepared from urine that may contain Mycobacterium smegmatis.

• Primary stain: Strong Carbol Fuchsin (contain BASIC fuchsin and Phenol)
• Decolourizer 20% SULPHURIC acid
• Counterstain LoelTler’s METHYLENE blue or 1% Malachite GREEN, PICRIC acid for color-blind workers

The cell walls of Mycobacterla are made up of waxy substance, Mycolic acid that Is relatively Impermeable to ordinary stainIng techniques. But, by apphcation of heat and a mordant (phenol), the cell can be stained The purpose of HEATING is to soften the waxy material of the cell wall and ALLOW the STAIN to enter the cell. Basic fuchsin is more SOLUBLE in phenol and phenol is a better solvent for LIPIDS and waxes.

The cell walls of Mycobacterla are made up of waxy substance, Mycolic acid that Is relatively Impermeable to ordinary stainIng techniques. But, by apphcation of heat and a mordant (phenol), the cell can be stained The purpose of heating is to soften the waxy material of the cell wall and allow the stain to enter the cell. Basic fuchsin is more soluble in phenol and phenol is a better solvent for lipids and waxes.

Ehrlich in 1882 discovered acid FASTNESS. The original method involved STAINING with aniline-gentian violet and decolourization with STRONG NITRIC acid.

It was later improved by Ziehl and Neelsen.

Ehrlich in 1882 discovered acid fastness. The original method involved staining with aniline-gentian violet and decolourization with strong nitric acid.

It was later improved by Ziehl and Neelsen.

Certain bacteria or their structures have the ability to retain the primary dye (strong carbol fuchsin) and resist clecolourization by weak MINERAL acids such as H2S04. HCI. Such bacteria or their structure are termed acid fast and this property is termed acid fastness. There are two types of acid fast staining, the hot METHOD and the COLD method. The hot method (Ziehl-Neelsen) involves heating the slide while the cold methods such as Kinyoun’s and Gabbett’s do not involve heating the slide.

Certain bacteria or their structures have the ability to retain the primary dye (strong carbol fuchsin) and resist clecolourization by weak mineral acids such as H2S04. HCI. Such bacteria or their structure are termed acid fast and this property is termed acid fastness. There are two types of acid fast staining, the hot method and the cold method. The hot method (Ziehl-Neelsen) involves heating the slide while the cold methods such as Kinyoun’s and Gabbett’s do not involve heating the slide.

• Kopeloll’ and Beerman’s (Primary STAIN: Methyl violet. decolourizer: acetone or alcohol-acetone mixture 1:1)
• JENSEN’s (Primary stain: Methyl violet, decolourizer: absolute alcohol. counterstain: NEUTRAL red)
• PRESTON and Morrell’s (Primary stain: crystal violet. decolourizer: iodine-acetone)
• A.igert’s (Primary stain: Carbol gentian violet. decolourizer: Aniline-xylol). This is used to stain tissue sections.

CANDIDA SPS

Candida sps

• Rapid presumptive DIAGNOSIS of diseases such as bacterial meningitis
• Selection of empirical ANTIBIOTICS based on Gram stain FINDING
• Selection of suitable culture media based on Gram stain finding
• Screening of quality of clinical specimens. such as sputum that should contain many pus cells and few epithelial cells
• COUNTING of bacteria
• Appreciation of morphology and types of bacteria in a clinical SPECIMEN 

DECOLOURIZATION is the most important step as this step differentiates between GRAM POSITIVE and Gram NEGATIVE bacteria. Over-decolourization can result in Gram positive bacteria appearing Gram negative and under-decolourization can result in Gram negative bacteria appearing Gram positive.

Decolourization is the most important step as this step differentiates between Gram positive and Gram negative bacteria. Over-decolourization can result in Gram positive bacteria appearing Gram negative and under-decolourization can result in Gram negative bacteria appearing Gram positive.

• When over-decolourized by either prolonged EXPOSURE to decolourizer or USING acetone ALONE.
• When cell wall gets damaged by exposure to LYSOZYME or cell wall acting antibiotics such as Penicillin.
• Old cultures, where cell wall is weakened or action of autolytic enzymes
• Those bacteria that are phagocytosed. where cell wall is acted UPON by lysosomal contents

• POSITIVE control: Staphylococci
• NEGATIVE control: E.coli. PUS CELLS

• Primary stain: Crystal violet. Methyl violet and GENTIAN violet
• Mordant: GRAMS IODINE, rarely Lugols iodine
• Decolorizer: Alcohol, acetone. acteone-alcohol mixture (1:1)
• Counterstain: Dilute carbol fuchsin. safranin, neutral RED. (Sandiford stain ROR Gonococcj

• Extremely SLENDER bacteria such as Treponema
• CELLS containing waxy SUBSTANCES impermeable to stain such as MYCOBACTERIA
• Minute intracellular bacteria such as Chlamydia and Rickettsia
• Cell organelles such as capsule. spore. flagella etc

It is the CYTOPLASM (ESPECIALLY the nucleic acid) that gets stained and not the cell WALL. PRESENCE of an intact cell wall is important for RETAINING Gram positivity. Cell wall deficient forms such as Mycoplasma and L forms are Gram negative.

It is the cytoplasm (especially the nucleic acid) that gets stained and not the cell wall. Presence of an intact cell wall is important for retaining Gram positivity. Cell wall deficient forms such as Mycoplasma and L forms are Gram negative.