doc therese Flashcards
1
Q
swabs collected in avian necropsy
A
tracheal and cloacal
2
Q
these should be checked after plucking the feathers
A
- trauma
- dog bites
- dermatitis
3
Q
what does opacity in the air sacs indicate
A
air sacculitis
4
Q
T/F: if there is fibrinous exudate in the coelom or air sacs, a swab should be placed into bacterial transport media
A
T
5
Q
T/F: bursa regresses as birds sexually mature
A
T
6
Q
T/F: fresh fecal or distal colon sample can be used to check for enteric parasites like coccidia
A
T
7
Q
what do exudates/plaques in the crop and esophagus indicate
A
Trichomonas/Candida infxn or hypovitaminosis A
8
Q
what does caseous exudate in the larynx and trachea indicate
A
ILT
9
Q
study of microscopic anatomy of cells and tissue
A
histology
10
Q
microscopic study of diseased tissue
A
histopath
11
Q
processing of tissue in such a manner as to enable microscopy/study of the tissue
A
histotech
12
Q
process by w/c constituents of cells are treated in a chemical so that they will withstand subsequent tx w/ various reagents w/ min. distortion or decomposition and keep the tissue in as life like manner as possible
A
fixation
13
Q
most common type of fixation
A
immersion (perfusion, freeze drying)
14
Q
fixatives that penetrate the cell to cross link proteins
A
- formaldehyde
- glutaraldehyde
15
Q
fixatives that dehydrate the cells and cause precipitation of proteins
A
- methanol
- ethanol
- acetone
16
Q
fixatives that cause changes in pH and hence denaturation of nucleic acids and salt formation
A
- acetic acid
- trichloroacetic acid
- zinc acetate
17
Q
examples of micro-anatomical fixatives
A
- formal saline
- formal calcium
- buffered neutral formalin
- Zenker’s fluid
- Bouin’s fluid
18
Q
examples of cytological nuclear fixatives
A
- Carnoy’s fluid
- Clarke’s fluid
- Fleming’s fluid
19
Q
examples of cytological cytoplasmic fixatives
A
- Champy’s fluid
- formal saline
- formal calcium
20
Q
examples of histochemical fixatives
A
- buffered neutral formalin
- cold acetone
- acid alcohol
21
Q
optimum size and thickness of sections
A
size: 2x2x0.3 cm
thickness: 3-4 cm
22
Q
it aims to embed the tissue in a solid medium firm enough to support the tissue and give it sufficient rigidity to enable thin sections to be cut and yet soft enough not to damage the knife or tissue
A
tissue processing
23
Q
stages of tissue processing
A
- dehydration - remove fixatives and water from tissue
- clearing - replacing dehydrating fluid w/ a fluid that is totally miscible w/ dehydrating fluid and embedding medium
- impregnation - replacing clearing agent w/ the embedding medium
- embedding
24
Q
T/F: hydrophilic agent is used in dehydration w/c attracts water from tissue
A
T
25
T/F: 75% is the 1st sol'n and used in increasing strengths
F - 70%
26
examples of hydrophilic agents used in dehydration
- ethanol (best)
- methanol
- methylated spirit
- isopropyl alcohol
27
main objective of clearing
transparent appearance of tissues
28
examples of clearing agents
- xylene (best)
- toluene
- chloroform
- citrus fruit oils
- cedar wood oil
29
it is the standard and preferred medium for embedding
paraffin wax
30
melting point of paraffin wax
52-56C
31
plastic point (solidification point)
10C below melting point
32
it is in pellet form and melts rapidly
paraplast
33
examples of alternative embedding media
- resin
- agar
- gelatin
- celloidin
34
precision instrument that cuts sections from the paraffin blocks, thin enough for examination under microscope
microtome
35
cellular components stained w/ basic dye (nucleus)
basophilic
35
cellular components stained w/ acidic dye (cytoplasm)
acidophilic
36
substance that forms a link b/w the tissue and stain to allow a staining rxn to take place
mordant (ex: ammonium and potassium alum for hematoxylin)
37
it is done to remove and clear the wax from the tissues
deparaffinization
38
possible results of inc deparaffinization
patches
39
it is necessary for the tissues to absorb the stain
hydration
40
T/F: most stains are aqueous or diluted in alcoholic sol'n
T
41
T/F: hydration is achieved using increasing strengths of alcohol
F - decreasing
42
it eliminates carrying over of 1 dye sol'n to the next
washing and rinsing
43
type of media that is used routinely for mounting to enable examination of tissue sections for any length of time
aqueous or resinous media
44
T/F: the use of cover slips and mounting ensures tissues are protected and preserved
T
45
most common stain applied for histological study and a.k.a. routine staining
H&E (hematoxylin and eosin stain)
46
in H&E, w/c is nuclear or cytoplasmic stain
hematoxylin - nuclear
eosin - cytoplasmic (counterstain)
47
types of hematoxylin
- Ehrlich's
- Mayer's
- Harris
- Mallory's
- Weigert's
48
interpretation of H&E
nuclei: blue
cytoplasm: pink/purplish pink
muscle fiber: deep red
RBCs: orange red
calcium: dark blue
mucin: grey blue
49
technique used to identify different cellular components w/ different colored dyes
differential staining
50
staining technique that is not used routinely
special stain
51
T/F: special stains are useful for identifying specific cellular components/FBs that are present in tissues
T
52
- special stain that is used to highlight the difference b/w collagen and other connective tissue such as muscle tissue
- used to identify the characteristic arrangement of fibers in different types of tumors
Van Gieson stain
53
Van Gieson stain is a mixture of what, causing collagen to become __________ and surrounding muscle tissues and blood cells to become ____________
- mix of picric acid and acid fuchsin
- RED (collagen)
- YELLOW (muscle tissues and blood cells)
54
- an acidophilic metachromatic dye that is attracted to nucleic acids (DNA and RNA)
- commonly used to identify mast cells granules, mucins, and cartilage
toluidine blue
55
toluidine blue makes nucleic acids stain ____________ and mucins and cartilage stain _____________
- nucleic acids (BLUE)
- mucins and cartilage (PURPLE)
56
a mix of 3 dyes used to differentiate muscles, collagen fibers, fibrin, and RBCs in connective tissue
Masson's trichrome stain (nuclear stain)
57
how to interpret Masson's trichrome stain
- nuclei (BLACK)
- cytoplasm, muscle, RBCs (RED)
- collagen (blue/green)
58
stains for glycogen and is used to identify mucoid substances and presence of fungi
PAS (Periodic acid Schiff)
59
interpretation of PAS
- PAS-positive material (MAGENTA)
- nuclei (BLUE)
60
lists of cryo-based methods that are low-temp ultrastructural immunocytochemical techniques
- cryofixation
- cryo-substitution
- cryo-embedding
61
sections that are used for rapid microscopic analysis (histo, histopath) and diagnosis of a specimen
crysosection
62
T/F: rapid diagnosis can help guide extraoperative patient care
F - intra
63
T/F: cryo-based methods are typically used in oncologic surgx
T
64
why perform cryo-based methods
- provide quick gross or microscopic diagnostics
- identify an unknown pathologic process
- determine dx extent/margin
- detect metastases
- simply identify a tissue
- process tissue to give prognosis
- confirm the presence of diseased tissue on permanent sections for diagnosis
65
why not to perform cryo-based methods
- no immediate ramifications for decision-making
- tissue is required for permanent processing
- frozen sections are known to exhibit severe artifacts that make appropriate interpretation difficult
- tissue is severely calcified and ossified
- possibility of major infxn (HIV, hepa B/C, TB)
66
material in cryo methods used for cold/rapid freezing and strong grip on blocks
chucks
67
ideal cutting thickness for sectioning and trimming
sectioning - 4-7 microns
trimming - 20-40 microns
68
a research and diagnostic technique that uses specific binding of Ab to an Ag to detect and localize specific Ags in cells and tissue in formalin fixed, paraffin embedded tissue
IHC (immunohistochemistry)
69
T/F: IHC uses light microscopy
T
70
IHC is widely used to aid in classifying __________
tumor/neoplasm
71
IHC flowchart
1. deparaffinization
2. rehydration
3. Ag retrieval
4. blocking
5. primary Ab
6. secondary Ab
7. chromogen application
8. counterstain
72
involves the pre-tx of tissue to retrieve Ags masked by fixation and make them more accessible to Ab binding
Ag retrieval
73
monoclonal or polyclonal, is titrated to optimize contrast b/w positively staining tissue and nonspecific bg staining, w/ the highest primary Ab dilution to prevent waste
primary Ab
74
Ab that targets a single epitope, tend to be more specific
monoclonal Ab
75
Ab that can bind many different epitopes, tend to be more sensitive
polyclonal Ab
76
recommended Ab concentration for initial titration
1-5 ug/mL
77
physical methods used to retrieve Ags
1. heat (microwave, pressure cooker, autoclave, water bath)
- most commonly used and provides good tissue morphology
2. ultz
- minimize protein changes caused by fixation
78
chemical methods used to retrieve Ags
1. enzyme digestion
- for epitopes w/c may lose antigenicity w/ heat and may destroy epitopes and tissue morphology
2. denaturant (formic acid, urea)
- formic acid for prion and neurofilament protein
3. detergent (Triton X-100, SDS)
- minimize contamination of sections
4. oxidizing (hydrogen peroxide)
- for some drugs such as bleomycin, daunomycin, pepleomycin
79
used to visualize the Ag-Ab rxn
secondary Ab
80
type of secondary Ab method where primary Ab is labeled and applied to the tissue in a quick one step process but this is not commonly used due to lack of signal amplification and thus the requirement for a higher concentration of Ab as well as the need to label each primary Ab
direct method
81
type of secondary Ab method where secondary Ab is labeled, allowing for signal amplification and use w/ many different primary Ab (horseradish peroxidases [HRP] or alkaline phosphatase [AP] w/c produces a colored product after incubatios w/ a chromogenic substrate such as diaminobenzidine [DAB])
indirect method
82
T/F: quality control is essential, and each run should include both positive and negative controls
T
83
bg staining can be caused by:
1. nonspecific Ab binding
- common in polyclonal Ab
2. endogenous peroxidase activity
- more problematic in tissues w/ a high concentration of hematopoietic components (bone marrow)
84
nonspecific Ab binding can be reduced by
preincubating the secondary Ab w/ normal serum from the same species or w/ a commercially available universal blocking agent (ex: goat serum)
