M5-PIGMENTS AND MINERALS; MOUNTING Flashcards
(155 cards)
1
Q
What is the process by which substances that absorb visible light and produce color are deposited in the body in normal or abnormal situations?
A
Pigmentation
2
Q
What are substances occurring in living matter that absorb visible light and can be seen without staining?
A
Pigments
3
Q
What are the three major categories of pigments?
A
Endogenous pigments
4
Q
Which pigments are produced within tissue to serve physiological functions or as by-products of metabolism?
A
Endogenous pigments
5
Q
Name the two groups of endogenous pigments.
A
Hematogenous (blood-derived) and Non-hematogenous (non blood-derived)
6
Q
Which pigment is an oxygen-containing conjugated protein found normally in red blood cells?
A
Hemoglobin
7
Q
What color does hemoglobin stain with eosin?
A
Pink/light red
8
Q
What color does hemoglobin stain with Heidenhain’s iron hematoxylin?
A
Black
9
Q
What color does hemoglobin stain with Mallory’s phosphotungstic acid hematoxylin?
A
Blue
10
Q
What is the most common hemoglobin derivative pigment?
A
Hemosiderin
11
Q
What color are hemosiderin granules?
A
Yellow to brown
12
Q
Where is hemosiderin commonly found?
A
Inside macrophages in liver
13
Q
Which pigment gives a positive reaction on PAS stain due to glycoproteins?
A
Hemosiderin
14
Q
What condition involves accumulation of iron in the liver without organ dysfunction?
A
Hemosiderosis
15
Q
What are “heart failure cells”?
A
Hemosiderin-laden macrophages seen in lungs
16
Q
What stain detects ferric ions combined with ferrocyanide producing a bright blue pigment?
A
Prussian blue stain
17
Q
What can remove hemosiderin from tissue sections?
A
10% sulfuric acid or dilute hydrochloric acid
18
Q
What is the difference between hemochromatosis and hemosiderosis?
A
Hemochromatosis involves excessive iron accumulation with organ dysfunction; hemosiderosis is iron accumulation without organ dysfunction
19
Q
Which pigment is an iron-free derivative of hemoglobin?
A
Hematoidin
20
Q
What color are hematoidin granules?
A
Yellowish or greenish
21
Q
In what pathological conditions is hematoidin found?
A
Infarcts
22
Q
Which pigment is hemoglobin minus the globin molecule?
A
Hematin
23
Q
Where is hematin commonly found?
A
Old blood clots
24
Q
What exogenous pigment is a black granule formed by malarial parasites?
A
Hemozoin
25
Where can hemozoin be seen?
Liver
26
Which method removes hemozoin from tissue?
Alcoholic picric acid method
27
What is the classic histochemical reaction used to detect iron in tissues?
Prussian blue stain
28
What are the components of the potassium ferrocyanide solution in Prussian blue stain?
Potassium ferrocyanide and hydrochloric acid
29
What is the role of hydrochloric acid in Prussian blue stain?
Unmask ferric iron
30
What is the optimal pH for Prussian blue stain?
1.5
31
What color does ferric iron stain in Lillie’s method?
Dark Prussian blue
32
What color does ferrous iron stain in Lillie’s method?
Dark Turnbull’s blue
33
What color is the background in Lillie’s method?
Light red
34
What color do hemosiderin and ferric salts stain in Perl's Prussian blue method?
Deep blue
35
What color do tissues and nuclei stain in Perl's Prussian blue method?
Red (counterstain)
36
What is the solution used in Gomori's Prussian blue stain for iron?
20% hydrochloric acid and 10% potassium ferricyanide
37
What counterstain is used in Gomori's Prussian blue stain?
Nuclear fast red
38
What color do iron pigments stain in Gomori's Prussian blue stain?
Bright blue
39
What reagent is used in Turnbull's blue stain for ferrous iron?
Potassium ferricyanide
40
What color does ferrous iron stain in Turnbull's blue stain?
Blue
41
What color do nuclei stain in Turnbull's blue stain?
Red
42
What pigment does Leuco Patent Blue V stain?
Hemoglobin peroxidase in RBCs and neutrophils
43
What color does hemoglobin peroxidase stain in Leuco Patent Blue V stain?
Dark blue
44
What color do nuclei stain in Leuco Patent Blue V stain?
Red
45
What are the components of the Leuco Patent Blue V stain solution?
Aqueous patent blue V
46
What pigments contain both conjugated and unconjugated bilirubin biliverdin and hematoidin?
Bile pigments
47
What color range do bile pigments and hematoidin exhibit?
Yellowish-brown to green
48
Which pigments appear yellow-brown in H&E staining and can be positive with swash ferricyanide?
Bile pigments and hematoidin
49
How can bile pigments be differentiated from lipofuscins?
Bile pigments are not autofluorescent and positive with small ferric ferricyanide lipofuscins show autofluorescence
50
What is the manifestation of excessive bilirubin accumulation?
Jaundice
51
What causes yellow coloration of the skin in jaundice?
Excessive bilirubin accumulation
52
What causes yellow coloration of the sclera in jaundice?
Ictericia
53
What is a common cause of jaundice in adults?
Liver damage
54
What is a common cause of jaundice in neonates?
ABO incompatibility or hemolytic anemia
55
Which technique converts bile pigments to green biliverdin and blue cholecyanin?
Modified Fouchet's technique
56
What is the counterstain used in Modified Fouchet's technique?
Van Gieson stain
57
What colors do bile pigments muscle and collagen stain in Modified Fouchet's technique?
Bile pigments emerald to blue muscle green-yellow collagen red
58
Which technique demonstrates bile pigments outside the liver by oxidizing bilirubin to blue-green biliverdin?
Gmelin technique
59
What is a limitation of the Gmelin technique?
Color is not permanent and results may be unreliable requiring repeated testing
60
Which method involves reduction of ferricyanide to ferrocyanide producing Prussian blue in the presence of ferric salts?
Schmorl's ferric ferricyanide method
61
What pigments stain dark blue in Schmorl's ferric ferricyanide method?
Bile lipofuscins melanin argentaffin cells chromaffin thyroid colloid
62
What color do nuclei stain in Schmorl's ferric ferricyanide method?
Red
63
What is the best fixative for Schmorl's ferric ferricyanide method?
10% buffered formalin
64
What counterstains are used in Schmorl's ferric ferricyanide method?
Neutral red nuclear fast red
65
What color is lipofuscin pigment?
Yellow-brown to reddish-brown
66
What process leads to the formation of lipofuscin?
Slow and progressive oxidation of lipids and lipoproteins
67
What is another name for lipofuscin?
Wear and tear pigment or brown atrophy
68
In which cells is lipofuscin commonly found?
Hepatocytes + cardiac muscle cells + adrenal cortex + brain + spinal cord + bone marrow + kidney
69
How is lipofuscin stained in frozen sections?
Oil soluble dyes
70
How is lipofuscin stained in paraffin embedded sections?
Basic fuchsin dyes
71
What color does lipofuscin stain in Gomori's aldehyde fuchsin technique?
Purple
72
What color is the background in Gomori's aldehyde fuchsin technique?
Yellow
73
In Mallory's fuchsin stain
what color does hemofuscin stain?
74
In Mallory's fuchsin stain
what color do nuclei stain?
75
Does hemosiderin stain in Mallory's fuchsin stain?
No it remains unstained
76
What pigment is brown or black and normally found in skin eyes and pigment-bearing neurons?
Melanin
77
What enzyme converts tyrosine to DOPA in melanin formation?
Tyrosinase
78
What granules package melanin?
Melanosomes
79
Is melanin soluble in strong alkali?
Yes
80
Does melanin react with iron or fat stains?
No
81
What benign melanocytic proliferation increases melanin deposition?
Nevus (mole/nunal)
82
What malignant tumor produces abundant melanin pigments?
Melanoma
83
Which monoclonal antibodies are used to detect melanoma?
HMB-45 + Melan A + NSE
84
What enzyme histochemical method is most specific for melanin?
DOPA-oxidase
85
What color deposit does DOPA-oxidase produce?
Brownish black
86
Which silver method relies on melanin's argentaffin property?
Masson-Fontana silver method
87
What color does melanin stain in Masson-Fontana method?
Black
88
What cells are chromaffin cells?
Neuroendocrine cells in adrenal medulla releasing catecholamines
89
Which stain visualizes chromaffin cells?
Chromium salts
90
What is the principle of Schmorl’s method?
Melanin reduces ferric ions to ferrous ions which combine with ferricyanide to form Turnbull’s blue
91
What color does melanin stain in Schmorl’s method?
Blue (Turnbull’s blue)
92
What counterstain is used in Schmorl’s method?
Aluminum-nuclear fast red or similar
93
How can melanin pigments be removed?
Bleaching with potassium permanganate or oxalic acid solutions
94
What are endogenous minerals commonly found in the body?
Calcium + iron + copper
95
Where is calcium normally present?
Hydroxyapatite in bones and teeth
96
What conditions are associated with abnormal calcium deposits?
Atherosclerosis + hyperparathyroidism + nephrocalcinosis + sarcoidosis + tuberculosis + some tumors
97
What stain is used to detect calcium phosphate crystals?
Alizarin Red S
98
What color does Alizarin Red S stain calcified deposits?
Orange
99
What is the principle of Von Kossa’s method?
Silver substitutes calcium and is reduced to metallic silver marking calcium location
100
What stain is used to detect copper accumulation?
Rubeanic acid and rhodanine stains
101
What disease involves defective copper transport leading to accumulation?
Wilson’s disease
102
What stain is most sensitive and specific for copper?
Lindquist's modified rhodanine technique
103
What color does copper stain in Lindquist's rhodanine technique?
Red to orange-red
104
What counterstain is used with rhodanine copper stain?
Mayer or Lillie-Mayer hematoxylin
105
What color do nuclei stain in rhodanine copper stain?
Blue
106
What is the crystallized form of uric acid that circulates as a breakdown product of purine metabolism?
Monosodium urates
107
Where are monosodium urates commonly deposited in patients with gout?
Joints and kidneys
108
What colors can monosodium urate crystals vary from?
Colorless to brown depending on crystal thickness
109
What fixation method must be used to preserve monosodium urate crystals?
95% or absolute alcohol
110
What conditions are associated with pathologic deposition of monosodium urates?
Gout + poor kidney function + kidney stones + arthritis
111
What type of birefringence do monosodium urate crystals show under polarized light with a red compensator?
Negative yellow or blue birefringence
112
What disease results from deposition of calcium pyrophosphate crystals in joint cartilage and may mimic gout?
Chondrocalcinosis (pseudogout)
113
What type of birefringence do calcium pyrophosphate crystals exhibit?
Positive birefringence
114
What stain uses methenamine-silver solution to stain urate crystals black on a green background?
Gomori’s methenamine silver stain
115
What is used to remove unreduced silver in Gomori’s methenamine silver stain?
Sodium thiosulfate
116
What is the most common exogenous mineral found in lung tissues of urban dwellers and smokers?
Carbon
117
What is the name of the lung condition caused by carbon deposition?
Anthracosis or coalworker’s pneumoconiosis
118
What mineral is found as grayish birefringent crystals in lungs of stone grinders?
Silica
119
What special type of silica crystal is found in lungs of asbestos workers?
Asbestos
120
What tumor arises from serous membranes and is associated with ferruginous bodies?
Mesothelioma
121
What are ferruginous bodies?
Fibers coated with protein-iron-calcium matrix with barbell shape
122
What causes artifact pigments in tissue sections?
Improper fixation + poor dehydration + improper reagents + poor microtome sectioning
123
What common solution removes excess stains in sections?
Acid alcohol
124
What do formaldehyde deposits look like?
Fine dark-brown or black crystal-like precipitates
125
What causes formaldehyde pigment formation?
Breakdown of laked hemoglobin when formalin buffer is exhausted and tissue becomes acidic
126
Are formaldehyde deposits birefringent?
Yes under polarized light
127
How can formalin pigment be prevented?
Use neutral buffered formalin instead of plain formalin
128
What solutions can remove formalin pigment?
1.8% picric acid in absolute alcohol + alcohol-ammonia solution + hydrogen peroxide + acetone + ammonium hydroxide + alkylphenol ethoxylate
129
What do mercuric chloride deposits look like?
Large irregular black precipitate clumps
130
How do mercuric chloride deposits appear under polarized light?
White
131
Which fixatives contain mercuric chloride?
B5 + Heidenhain’s Susa + Helly’s + Zenker’s fluid
132
How are mercuric chloride deposits removed?
Saturated alcoholic iodine during dehydration followed by bleaching with weak sodium thiosulfate
133
What do osmium tetroxide deposits look like?
Black deposits on tissue
134
How are osmium tetroxide deposits removed?
Hydrogen peroxide and 70% alcohol or 0.5% potassium permanganate
135
What do chrome deposits look like?
Fine brown or black granules in chromate-fixed tissues
136
How are chrome deposits removed?
Washing with acid alcohol
137
How can chrome deposits be prevented?
Washing tissue in running tap water before dehydration
138
What is the usual location for tattoo pigments?
Skin
139
What other purposes can tattoo pigments serve besides skin decoration?
Marking anatomic or surgical landmarks and aiding tissue during gross dissection and embedding
140
What pigment is usually introduced by talc from gloves during tattooing?
Starch or talcum powder
141
Which stains are starch or talcum powder positive with?
PAS and GMS
142
What unique configuration does starch or talcum powder show under polarized light?
Maltese cross
143
What dyes does starch or talcum powder have affinity for?
Auramine O and rhodamine B
144
What color does starch or talcum powder fluoresce under fluorescence microscopy?
Yellow
145
What is the purpose of adhesives in mounting histologic sections?
To make sections stick well to slides especially during exposure to acids and alkalis
146
Name a commonly used adhesive for mounting sections?
Mayer’s egg albumin
147
What is a disadvantage of Mayer’s egg albumin?
Retains some stain causing dirty background
148
List other adhesives used besides Mayer’s egg albumin
Dried albumin + Gelatin (1%) + Gelatin-formaldehyde mixture + Poly-L-Lysine + APES (3-aminopropyltriethoxysilane)
149
What is the function of mounting medium?
Bonds specimen + slide + and coverslip with a clear durable film + preserves slides + prevents image distortion
150
What are characteristics of a good mounting medium?
Colorless + transparent + miscible with xylene and toluene + does not dry non-stick or harden quickly + protects section from damage and chemical changes + resistant to contamination + does not cause tissue shrinkage or leach stain + compatible with adhesives + sets without crystallizing cracking or shrinking
151
Name some aqueous mounting media
Water + Glycerin + Farrant’s Medium + Apathy’s Medium + Brun’s Fluid
152
Name some resinous mounting media
Canada Balsam + DPX (Dibutyl Phthalate and Xylene) + XAM + Clarite
153
What is Canada Balsam?
Natural resin from Canadian tree Abus Balsamea + transparent + colorless oleoresin + adheres firmly to glass + sets hard without granulation
154
What is cover slipping?
Placing a thin piece of plastic or glass over tissue section to protect it and improve optical quality
155
What is ringing?
Sealing margins of coverslip to prevent fluid escape + evaporation + and to fix coverslip in place
