Microbiological Stains (Wk 13) Flashcards
Why is the Wade-Fite stain necessary when ZN exists
Demonstrates M. leprae which is acid-fast but NOT acid/alcohol-fast
Proteoglycan layer of bacterial cell walls is known as?
Peptidoglycan
How to identify cytomegalovirus?
CMV-infected cells have large nuclei w/ basophilic inclusions
What is used for prions decontamination
1M NaOH
What is used to for differentiation in ZN stain?
Acid/alcohol
2 stains that can demonstrate hepatitis
Shikata’s orcein
Phloxine tartrazine
Primary stain in Ziehl-Neelson?
Carbol fuchsin
Aside from Mycobacteria, ZN can also stain what 2 types of bacteria?
Actinomyces and Nocardia
3 components of carbol fuchsin?
Basic fuchsin
Alcohol
Phenol
Type of silver used in Grocott’s
Methenamine silver
2 specialized argyrophil methods to demonstrate Spirochetes
Warthin-Starry
Dieterle’s
Grocott’s is an ______ reaction (type of silver rxn) and is performed at ___degC
argentaffin
60degC
Gram positives have a thicker ________ layer than Gram negatives
peptidogylcan
Demonstrates hepatitis, somewhat specific for HepB surface antigen
Shikata’s orcein
This component in Mycobacteria help them retain ZN stain, but is also responsible for preventing them from staining with Gram’s
mycolic acid
2 stains that will demonstrate Helicobacter
Giemsa
Dieterle’s
2 components of Twort’s (counterstain for Gram’s)
Safranin (cationic), stains Gram neg bacteria
Fast green (anionic), stains tissue
M. leprae is localized to _______
nerves
Grocott - what is used to remove excess chromic acid
Sodium bisulfite
What part of fungi get stained by the Grocott methenamine silver method
carbohydrates in the fungal capsule
What are the 2 cationic dyes in Gram’s
Crystal violet, safranin
Used to correct pH in Grocott’s
Borax
Counterstain in Grocott’s
Fast green
Used to diagnose herpes virus
Tzanck smear
Tissues are deparaffinized with __________ for the Wade-Fite stain
peanut oil/xylene
Why is heat not required in ZN
Phenol drives stain into the bacteria
Typical counterstain for ZN?
Methylene blue
This component of the ZN stain is responsible for driving the primary stain into the bacteria
phenol
Spirochetes stain: _________ is used to reduce silver to a visible deposit
hydroquinone
Tzanck smear for herpes is stained with?
Giemsa
What is the tissue stain in Gram’s counterstain
Fast green (anionic)
Reagent used for differentiation in Wade-Fite?
Sulfuric acid
Oxidizing agent in Grocott and why it’s used
Chromic acid - very strong oxidizing agent
OVER-oxidizes glycogen + neutral glycoproteins
