Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

cellular pathology year 2 > Lecture 2 - staining > Flashcards

Lecture 2 - staining Flashcards

1
Q

why do we stain tissue

A

allows you to visualise its ultrastructure with more clarity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

whats another word for direct staining

A

histological staining

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what does staining actually do

A

colours an active component of the tissue

Direct interaction between a dye or a staining solution and the tissue e.g. Gomori trichome blue for skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

whats another word for indirect staining

A

histochemical staining

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what happenes in indirect staining

A

chemical reaction

links dye to tissue

link called mordant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what does the chemical reation of indirect staining allow

A

localisation of specific substance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what does immunohistochemical staining rely on

A

antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

is Immunohistochemical staining direct or indirect

A

both

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does Immunohistochemical staining allow

A

visualisation of specific molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is indirect staining in terms of antibodies

A

primary antibody that is unconjugated and then a secondary antibody that is conjugated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is direct staining in terms of antibodies

A

primary antibody that is fluorescently conjugated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how many steps is indirect immunohistochemistry

A

2 steps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

how many steps is immunofluorescence

A

1 step

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

factors that affect staining

A

quality of fixation

choice of fixative

time for stain

pH of staining

tissue thickness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what happens if there is an overfix

A

may go in too much

blown apart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what happens if the wrong fix is used

A

wont see what you want to

17
Q

what are the most common stains

A
  • H and E stain in histopathology
  • Gram stain in microbiology
  • Romanowsky in haematology
18
Q

what is haematoxylin and eosin

A

haemotoxylin - basic dye, carries positive charge

eosin - acidic dye, carries negative charge

19
Q

what are basophilic and acidophilic

A

basophilic - acidic elements in tissue attracted to basic dyes

acidophilic - basic elements in tissue attracted to acidic dyes

20
Q

what does haemotoxylin bind to

A

structures like DNA

21
Q

what does eosin bind to

A

non DNA structures including proteins

22
Q

what does nuclei attract

A

haemotoxylin

stains dark blue

23
Q

what do cytoplasm, collagen and muscle attract

A

eosin

stains magenta

24
Q

what are the two types of staining

A

progressive

regressive

25
Q

what is differentiation of staining

A

removal of excess stain

makes sure colour is retained only by wanted structures

usually does with acidic alcohol

26
Q

whats the difference between muscle and connective tissue staining

A

muscle - deep pink

connective tissue - pale pink

27
Q

what happens when the section of tissue isn’t cut evenly

A

staining will be uneven

better to use thin section of tissue

patches of stains

28
Q

what is chattering

A

creates uneven parallel lines in the image following staining

dye not applied enough

29
Q

can computer algortihsm remove chattering

A

yes, but unclear and distorted image is produced

30
Q

why is non-specific staining a problem

A

stain can sometimes stick to non-tissue elements on slide

stain can bind elements of broken tissue generating an artificial signal

31
Q

how can you avoid non-specific staining

A

positive control -> perform staining on a well characterised tissue

negative control -> tissue processed in the same way without the dyes

32
Q

how is non specific staining controlled in the lab

A

Every section of the lab has quality control logs as part of standard operating procedures (SOPS)

External quality control lab participates in National External Quality Assurance Scheme

Sends samples for testing once a month

33
Q

what do histopathologists do

A

Provides written report on surgical biopsy and cytology specimens

Provides direct consultations on cases

Contributes to equipment selection and technical
methods

Supports and contributes to postgraduate teaching

cellular pathology year 2 (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions