M2 Lab Methods

Question 1

what is procedure

Answer 1

handling specimen
lab processing and reporting
interpretation and use of info

Question 2

what do u do in lab analysis

Answer 2

isolate and identify organism

• sample
• timing
• handling
• request form

Question 3

how is a sample taken fro purulent infection (pus forming)

Answer 3

aspirate of pus - drain
prevent contamination
maintain anaerobes

Question 4

how to sample mucosal infections

Answer 4

yeast, swab and oral wash

herpes, lesions swab

Question 5

how to sample caries and per disease

Answer 5

complex pic involving mix of organisms

Question 6

how to do samples for culture

Answer 6

results = 2-5 days
streaked blood agar (aerobic/anaerobic)
colonies then indie cosines
antibiotic sensitivity

Question 7

what does culturing do

Answer 7

determine viability (aerobes Vs anaerobes)
component species
provides pure material (single colony)

Question 8

what is culturing sequence

Answer 8

primary inoculum
second streak
3rd streak
streak to single colonies

Question 9

what is general media

Answer 9

transport media
- sloppy agar, incl charcoal prevents desiccation and abs toxic agents

rich excess of nutrients

Question 10

what is enrichment media

Answer 10

addition of blood/serum/extracts will support growth of fastidious organisms
blood agar also - haemolytic profile determined

Question 11

what si selective media

Answer 11

presence of specific substance permits the growth of one organism over another

Question 12

what re some examples of selective media

Answer 12

mannitol salt agar

salmonela-shigella

Question 13

what is differential media

Answer 13

incroportio of chems produces visible changes in colonies that facilitate identification

Question 14

what are some examples of differentiate media

Answer 14

macconkay agar
- bile salts & crystal violet
eosin & methylene blue

Question 15

what can be used for identification

Answer 15

microscopy - single colony or pus sample

• pure culture
• shape, size, grouping
• structures
• staining

Question 16

what are the cocci structures

Answer 16

single
pair
cluster
chains

Question 17

what are the rod bacilli structure

Answer 17

single
chain
curved rod
spiral

Question 18

what is one species with many colony phenotypes

Answer 18

bacillus subtilis

Question 19

what is metabolic profiling

Answer 19

biochem characterisation

utilisation of carbon sources and amino acids

Question 20

what is exo enzyme production

Answer 20

catalase
coagulase
hydrolysis of lipid
urease

Question 21

whats urease

Answer 21

urea converted to ammonia & CO2

Question 22

what causes fermentation

Answer 22

lactose

Question 23

what are serological tests

Answer 23

host immune response to Ag by rising of Abs

Question 24

what are Ab specific to

Answer 24

microbe or single component

Question 25

what else does serological tests do

Answer 25

detects presence of sp IgM Ab to virus demo in vitro bu agglutination rapid detection of viruses serotype bac indeitifacton

Question 26

what are immunological techniques

Answer 26

``` difficult to identify pathogens artificially raised sp antibodies - agglutination reactions - DFA test - ELISA ```

Question 27

what is aggltination

Answer 27

antibody to antigen with latex bead - red blood cell | caring clot

Question 28

what is DFA fluorescence tect

Answer 28

one step - org expo to Ab with attached dye, organism bind toAb and be seen two step - similar to one step Ab at start not dye, instead secondary Ab dyed

Question 29

what is ELISA

Answer 29

enzyme linked immunosorbent assay

Question 30

how do u do ELISA

Answer 30

``` coat wells with antigen wash add antibody test wash add enzyme conjugate wash add chromogenic enzyme substrate and read colour change ```

Question 31

what are virulence test

Answer 31

virulence factor can be critical in pathogenesis (adhesion, toxin) in vitro antibody recognition, DNA hybridisation

Question 32

what is DNA technology

Answer 32

sp primers amplify sp peice dna | PCR

Question 33

what is MALDI-TOF

Answer 33

matrix assisted laser desorption ionisation time of fight

Question 34

what are the features of MALDI_TOF

Answer 34

powerful rapid precise cost effective

Question 35

what does madli tof do

Answer 35

gen series of ions from a sample dept on its constituents sep ions accord to mass detects proteins results in characteristic signature