MD Exam 2

Question 1

Detection system in MD should have three qualities

Answer 1

Sensitivity, specificity, simplicity

Question 2

Sensitivity

Answer 2

the test must be able to detect very small amounts of target even in the presence of other molecules

Question 3

Specificity:

Answer 3

the test yields a positive result for the target molecule only

Question 4

Simplicity:

Answer 4

the test must be able to run efficiently and inexpensively on a routine basis

Question 5

Regulation Organization and Agents

Answer 5

CLIA
FDA
CMS
CAP
JCAHO
COLA

Question 6

Clinical validation: Accuracy

Answer 6

a

Question 7

Clinical validation: Precision

Answer 7

a

Question 8

Clinical validation: analytic sensitivity

Answer 8

a

Question 9

Clinical validation: Analytical specificity

Answer 9

a

Question 10

Clinical validation: Diagnostic specificity

Question 11

What do we use to lyze cells for NA isolation and analysis?

Answer 11

Detergent SDS, Tween 20

Question 12

What methods do we use for assessment of quality and quantity?

Answer 12

UV Spectrophotometry (O.D 260-280) and fluorescent dyes

Question 13

OD260=

Answer 13

1.0 ~50 ug/ml of dsDNA or 4- ug/mL of RNA or ssDNA

Question 14

After you isolate the DNA you can do direct detection of NA w/

Answer 14

1. Restriction endonuclease enzyme digestion
2. Gel electrophoresis and ETBr Stain
3. Restriction Fragment Length Polymorphism (RFLP)

Question 15

Restriction Endonucleases (RE) are found only in

Answer 15

microorganisms

Question 16

RE’s are homodimers that recognize

Answer 16

symmetric dsDNA (palindromes)

Question 17

Palindromes:

Answer 17

Read the same in both directions
Recognize specific sequences of 4, 5, or 6 nucleotides
Cut by breaking phosphodiester bonds in both strands
Cut DNA into smaller pieces

Question 18

Gel electrophoresis separates molecules on the basis of __________ by:

Answer 18

their charge and size; retard the passage of molecules according to their size and shape

Question 19

How do (-) and (+) particles move in gel electro

Answer 19

The negatively charged particles move toward the positive electrode while the positive charged particles move toward the negative electrode

Question 20

What are the two types of gels?

Answer 20

Agarose and acrylamide

Question 21

HB^S produces

Answer 21

sickled cell RBC

Question 22

Homozygotes for HBs are anemic. What is the lost site?

Answer 22

Mst II

Question 23

Blotting/Hybridization Techniques uses

Answer 23

specific probes that are labelled specific sequences of DNA can be identified

Question 24

To recognize RNA, which blotting method do we use?

Answer 24

Northern blot (using DNA or RNA probes)

Question 25

To recognize DNA, which blotting method do we use?

Answer 25

Southern (using DNA or RNA probes)

Question 26

To recognize protein, which blotting method do we use?

Answer 26

Western (antibody)

Question 27

Probes are

Answer 27

ssDNA that will base pair with a complementary sequence of either RNA or DNA

Question 28

ID of target detected/identified by labeling probes with:

Answer 28

Radioactive (P32) label Chemiluminescent compound Fluorescent compound Enzymatic label (alkaline phosphatase/horseradish peroxidase with substrates to get color reaction done)

Question 29

ID of target detected/identified by labeling probes with:

Answer 29

Radioactive (P32) label Chemiluminescent compound Fluorescent compound Enzymatic label (alkaline phosphatase/horseradish peroxidase with substrates to get color reaction done)

Question 30

Allele Specific Oligonucleotide Probes (ASO’s) must have

Answer 30

2 probes (1 for each allele)

Question 30

Allele Specific Oligonucleotide Probes (ASO’s) must have

Answer 30

2 probes (1 for each allele; 1 normal, one mutant)

Question 31

ASO is used for detection of Cystic fibrosis with what two probes?

Answer 31

AsOn = WT ASOx = mutant cystic fibrosis gene (loss of phenylalanine 508)

Question 32

Hybrid capture assays uses antibody capture assay to detect/capture

Answer 32

hybrid (DNA/RNA) molecules

Question 33

Hybrid capture assay i used to detect

Answer 33

HPV

Question 34

Each PCR cycle increases the number of strand by multiples of

Answer 34

2 or 2^n

Question 35

Taq polymerase is isolated from bacterium

Answer 35

T. aquaticus

Question 36

RT-PCR is done for

Answer 36

RNA viruses to convert into DNA

Question 37

NASBA and TMA are more used in clinical settings because

Answer 37

they belong to isothermal PCR and they begin with RNA molecules

Question 38

Signal amplification is not a target PCR, it targets

Answer 38

signals with bDNA branched DNA probes

Question 39

Signal amplification quantifies

Answer 39

HIV-1, HCV RNA

Question 40

Gold standard of molecular?

Answer 40

DNA sequencing

Question 41

Sanger sequencing requires

Answer 41

ssDNA template, DNA primer, DNA polymerase, labeled nucleotides and modified nucleotides to terminate DNA elongation

Question 42

ddNTPs will

Answer 42

prevent addition of further nucleotides

Question 43

FISH is used for cytogenetics by detecting

Answer 43

large fragment of DNA and chromosomal abnormalities