Pigments (Wk 10)

Question 1

___________ forms a dark green chelate in the presence of copper

Answer 1

Rubeanic acid

Question 2

Appearance of asbestos in lung tissue?

Answer 2

Brown, beaded dumbbell appearance

Question 3

What is a nevus

Answer 3

Benign lesion

Question 4

Von Kossa’s - how are visible deposits formed?

Answer 4

• Treat tissues w/ silver nitrate

- Light source reduces silver to visible deposit

Question 5

2 artifact pigments

Answer 5

Formalin

Mercury

Question 6

Colour and location of bile

Answer 6

Yellow-brown

Liver

Question 7

Where is chromaffin pigment normally found?

Answer 7

Adrenal medulla

Question 8

Demonstrated by Turnbull’s Blue stain

Answer 8

Ferrous iron

Question 9

Melanin immunohistochemical marker

Answer 9

S100

Question 10

2 methods that demonstrate calcium

Answer 10

Von Kossa (indirect)
Alizarin Red (direct, but also stains Mg)

Question 11

3 categories of pigments

Answer 11

• Endogenous
• Artifact
• Exogenous + minerals

Question 12

Can be removed w/ iodine and then sodium thiosulphate

Answer 12

Mercury artifact

Question 13

3 non-hematogenous pigments

Answer 13

Melanin
Lipofuscin
Chromaffin

Question 14

What coats asbestos

Answer 14

Proteins + hemosiderin

Question 15

Colour and location of hemosiderin

Answer 15

Yellow-brown

Intracellular (macrophages), sites of hemorrhage

Question 16

Substances which occur in living matter and absorb visible light

Answer 16

Pigments

Question 17

This amino acid is acted on by an enzyme to be converted to melanin

Answer 17

Tyrosine

Question 18

How is melanosis coli demonstrated

Answer 18

Methods that demonstrate lipofuscin

Question 19

What reduces ammoniacal silver in Masson-Fontana method?

Answer 19

Melanin

Question 20

Typical locations of lipofuscin

Answer 20

Liver
Heart
Brain

Question 21

2 possible sources of INTERFERENCE causing weak bonds in Congo Red

Answer 21

• Salt

- Alkalinity

Question 22

How is hemoglobin demonstrated?

Answer 22

Diamino benzidine + H2O2
OR
Leuco patent blue

Question 23

Main difference in the components of Perl’s vs Turnbull’s stain?

Answer 23

Perl’s - ferrOcyanide

Turnbull’s - ferrIcyanide

Question 24

Brown pigment sometimes in macrophages in colon (misc. pigment)

Answer 24

Melanosis coli

Question 25

Endogenous pigments can be further subdivided into these 3 categories

Answer 25

Hematogenous Non-hematogenous Endogenous minerals

Question 26

_________ forms a red product w/ copper

Answer 26

Rhodanine

Question 27

Amyloid tissue must be cut at this thickness

Answer 27

6-10 microns

Question 28

3 exogenous pigments/minerals

Answer 28

Tattoo pigment Carbon Asbestos

Question 29

Why isn't formalin required in MF stain?

Answer 29

argentaffin method = no external reducing agent required

Question 30

Stain that demonstrates hemosiderin

Answer 30

Perl's Prussian Blue

Question 31

Tyrosine -> _______ -> melanmin

Answer 31

DOPA

Question 32

2 components of Fouchet's

Answer 32

Trichloroacetic acid | Ferric chloride

Question 33

2 other argentaffin substances (not melanin) that may also stain in the MF method

Answer 33

Chromaffin | Lipofuscin

Question 34

Weak amyloid staining may be due to these 3 factors

Answer 34

- Prolonged formalin fixation - Old control sections - Old reagents

Question 35

What do calcium deposits in tissue represent?

Answer 35

Previous inflammation or injury

Question 36

3 endogenous mineral pigments

Answer 36

Calcium Copper Urates

Question 37

Stain that demonstrates bile and how

Answer 37

Fouchet's Oxidizes bilirubin to green biliverdin

Question 38

Method for demonstrating melanin that involves ferric ions

Answer 38

Schmorl's

Question 39

How to demonstrate asbestos?

Answer 39

Perl's stain of asbestos - shows hemosiderin coating the asbestos

Question 40

2 components of Turnbull's blue

Answer 40

Acid | Potassium ferricyanide

Question 41

2 methods that demonstrate copper

Answer 41

``` Rubeanic acid (green) Rhodanine (red) ```

Question 42

Which stain is this? Melanin reduces ferric to ferrous ions and then combines with ferricyanide

Answer 42

Schmorl's

Question 43

AKA "wear and tear" pigment

Answer 43

Lipofuscin (results from breakdown of lipids)

Question 44

Masson-Fontana counterstain

Answer 44

Neutral red

Question 45

2 components of working iron reagent in Perl's Prussian blue

Answer 45

1:1 ratio HCl + potassium ferrOcyanide