Pigments and Minerals Flashcards
What is the difference among artifactural, endogenous, and exogenous pigments?
Fixation pigments are artifactural. Exogenous pigments form outside of the body, and endogenous pigments form inside the body.
What does argyrophil mean?
Having an affinity for silver. The first part is from Latin for silver: argentum. The second part is from Greek and means attracted to.
Name some reducing agents for silver stains.
Bright light, Formaldehyde, Hydroquinone.
Name some silver stains for argyrophilic tissue components.
Both Grocott’s and Gomori’s Methenamine Silver (GMS), Von Kossa, Jones, Steiner & Steiner, Warthin Starry, Dieterle, Bielschowsky
What can happen if you don’t wear gloves when you perform a Von Kossa silver stain?
When you leave for the day and walk out into bright sunlight, the silver on your hands will get reduced to a brownish stain that will gross out the cashier at the supermarket.
What is different about the Fontana-Masson silver staining technique?
It stains tissue components that are argentaffin, meaning they have an affinity for silver AND can reduce it. There is no need for a reducing agent with this method.
What is the difference between argyrophil and argentaffin?
Both are tissue components that have an affinity for silver (the -phil and -affin suffixes tell us this), but only argentaffin tissue can reduce it.
Argentaffin tissue, such as melanin, can reduce the silver salts in the Fontana-Masson stain. What other stain can be reduced naturally by argentaffin tissue?
The Schmorl technique uses argentaffin tissue substances to reduce the ferric ions in the staining solution to ferrous ions that then combine with ferrocyanide to make ferrous ferrocyanide, or Turnball Blue.
What is the difference between Turnball Blue and Prussian Blue?
Prussian Blue stains ferric iron (prussian and ferric both contain the letter “i”), and Turnball Blue (slightly lighter in color) stains ferrous iron.
Would Nuclear Fast Red be a good counterstain for an iron stain?
Yes. Whether it’s Prussian Blue or Turnball Blue, Nuclear Fast Red should be an excellent counterstain.
Why do we perform a Prussian Blue stain?
To detect ferric iron in tissue. Too much iron stored in the body can lead to diabetes and organ failure.
What is another name for the Prussian Blue stain?
Perls or Perls Prussian Blue, after a German pathologist. Prussia was part of Germany. It is the blue of the Prussian Army, Piccaso’s Blue period, and blueprints. It was a Crayola crayon until the name was changed because school children didn’t know what Prussia was.
Why would we perform a Turnball Blue Iron stain.
To detect ferrous iron (which is toxic) in tissue.
Name 2 stains that detect melanin.
Fontana-Masson and Schmorl. Schmorl stain is shown.
How can you prove the dark staining in a Fontana-Masson is melanin?
By running a Melanin Bleach control along with a positive control.
This is Hall’s Bilirubin. What is staining green here, and what is the counterstain?
Bile. The counterstain is Van Giesen.
