Molecular Techniques & POCT

Question 1

assays that target nucleic acid instead of protein, are the

latest development in clinical laboratory testing.

Answer 1

Molecular techniques,

Question 2

requires the release of DNA or RNA from the cell

followed by its purification and quantitation.

Answer 2

Nucleic acid extraction

Question 3

is a short strand of DNA or RNA of a known sequence that

is well characterized and complementary for the base sequence on the test target.

Answer 3

nucleic acid probe

Question 4

based on the reversible complementary base

pairing of nucleotides.

Answer 4

principle of hybridization

Question 5

Southern blot
Northern blot
In situ hybridization
Restriction fragment length polymorphism

Answer 5

Probe Techniques-Unamplified:

Question 6

PCR
RT-PCR
Transcription based amplification systems
Transcription-mediated amplification
Nucleic acid sequence-based amplification
Strand displacement assay

Answer 6

Probe Techniques-Target Amplification

Question 7

Probe Techniques-Probe Amplification

Answer 7

Ligase chain reaction

Question 8

Probe Techniques-Signal Amplification

Answer 8

Branched DNA assay

Question 9

are the simplest types of solid

support hybridization assays.

Answer 9

Dot blot and sandwich hybridization assays

Question 10

clinical samples are applied
directly to a membrane surface. The membrane is heated to denature or separate
DNA strands, and then, labeled probes are added.

Answer 10

dot blot assay,

Question 11

modification of the dot blot procedure. It was
designed to overcome some of the background problems associated with the use
of unpurified samples.

Answer 11

Sandwich hybridization

Question 12

In this method, DNA is extracted from a sample using a
phenolic reagent and then enzymatically digested using restriction endonucleases
to produce DNA fragments.

Answer 12

Southern blot.

Question 13

is a technique that
evaluates differences in genomic DNA sequences. This technique can help
establish identity or nonidentity in forensic or paternity testing or to identify a
gene associated with a disease.

Answer 13

Restriction fragment length polymorphism (RFLP)

Question 14

RNA is extracted, digested, electrophoresed, blotted, and

finally probed.

Answer 14

Northern blot

Question 15

for the
detection of human papillomavirus (HPV) is a solution-phase hybridization
assay that uses an antibody specific for DNA/RNA hybrids to “capture” and
detect the hybrids that are formed during the solution hybridization of HPV
DNA in the sample with an unlabeled RNA probe.

Answer 15

Digene Hybrid Capture 2 assay

Question 16

In this type of
setting, both the target nucleic acid and the probe are free to interact in a reaction
mixture, resulting in increased sensitivity compared with that of solid support
hybridization.

Answer 16

solution hybridization

Question 17

is considered the “gold standard” for many molecular
applications from mutation detection to genotyping, but it requires proper
methodology and interpretation to prevent misinterpretation.

Answer 17

DNA sequencing

Question 18

is a relatively new technique for a short to moderate
sequence analysis that is based on the release of pyrophosphate during DNA
synthesis as each dNTP (deoxyribonucleotide triphosphate) is incorporated with
elongation of DNA.

Answer 18

Pyrosequencing

Question 19

are very small devices used to examine DNA, RNA, and

other substances.

Answer 19

Biochips/microarrays

Question 20

is an amplified
hybridization technique that enzymatically synthesizes millions of identical
copies of the target DNA to increase the analytic sensitivity.

Answer 20

PCR

Question 21

When the target is microbial RNA or mRNA, the RNA must be
enzymatically converted to DNA by reverse transcriptase; the product, cDNA,
can then be analyzed by PCR.

Answer 21

RT-PCR

Question 22

allows for direct measurement of amplicon accumulation during the exponential
phase of the reaction.

Answer 22

“Real-time” RT-PCR

Question 23

defined as the value at which the sample fluorescence crosses the threshold.

Answer 23

The threshold cycle (CT)

Question 24

A thermostable enzyme; 5’-3’ polymerase activity

Answer 24

Taq polymerase

Question 25

Needed for polymerase & nuclease activities of Taq polymerase

Answer 25

Magnesium salts

Question 26

is defined as the temperature at which 50% of the

DNA is double stranded and 50% is single stranded.

Answer 26

DNA
melting temperature (Tm)

Question 27

detects target RNA and

involves continuous isothermic cycles of reverse transcription.

Answer 27

self-sustained sequence replication or

transcription-based amplification system (TAS)

Question 28

The principle of the reaction was a two-
step process that involved generation of cDNA from the target RNA followed by reverse transcription of the cDNA template into multiple copies of RNA.

Answer 28

Transcription-based amplification

Question 29

One set of
primers incorporates a specific restriction enzyme site that is later attacked by an

endonuclease. The resulting “nick” created in only one strand by the restriction
enzyme allows for displacement of the amplified strands that then, in turn, serve
as targets for further amplification and nick digestion.

Answer 29

Strand displacement amplification (SDA)

Question 30

is a probe amplification technique
that uses two pairs of labeled probes that are complementary for two, short-target
DNA sequences in close proximity.

Answer 30

ligase chain reaction (LCR)

Question 31

are designed to increase the signal strength by

increasing the concentration of the label.

Answer 31

Signal Amplification

Question 32

are useful in identifying microorganisms in a patient

specimen or confirming an organism isolated in culture.

Answer 32

Nucleic acid probes

Question 33

defined as “those analytical patient-testing
activities provided within the institution, but performed outside the physical
facilities of the clinical laboratories.”

Answer 33

Point-of-care testing (POCT)

Question 34

“near-patient testing,”
“extra-laboratory analyses,”
“ancillary testing,” 
“bedside testing,”
“physician's office testing,”
“alternative site
testing.”

Answer 34

POCT

Question 35

The major advantage of POCT

Answer 35

faster delivery of results.

Question 36

CLIA certificate: Issued to a laboratory to perform only waived tests

Answer 36

Certificate of Waiver

Question 37

CLIA certificate: Issued to a laboratory that enables the entity to conduct moderate- or high-complexity lab testing or both

Answer 37

Certificate of Registration

Question 38

CLIA certificate: Issued to a lab in which a physician, midlevel practitioner, or dentist performs no tests other than the microscopy procedures

Answer 38

Certificate for PPMPs

Question 39

CLIA certificate: Issued to a lab after an inspection that finds the lab to be in compliance with all applicable CLIA reqs

Answer 39

Certificate of Compliance

Question 40

CLIA certificate: Issued to a lab on the basis of the lab’s accreditation by an accreditation organization approved by the Health Care Finance Admin

Answer 40

Certificate of Accreditation

Question 41

3 categories in POCT complexity

Answer 41

Waived tests
Moderate-complexity tests
High complexity tests

Question 42

of tests defined by CLIA, such as
dipstick tests, urine pregnancy tests, and blood glucose monitoring devices,
which are subject to the lowest level of regulation and are cleared by the FDA
for home uses.

Answer 42

Waived tests

Question 43

4th category of POCT: These tests
involve the use of a microscope, limited to bright-field or phase-contrast
microscopy. Generally, the specimens are labile and cannot survive transport to a
clinical laboratory.

Answer 43

provider-performed microscopy procedures,

or PPMPs

Question 44

TRUE/FALSE: There are usually no QC materials available for PPMP;
however, the individual performing PPMP endures the certification process and
participates in proficiency testing.

Answer 44

TRUE

Question 45

scientific

oversight of the POCT

Answer 45

technical consultant

Question 46

required to provide

clinical and medical advice.

Answer 46

clinical consultant

Question 47

monitors day-to-day
activities of testing personnel, and it is the responsibility of the ____ to
coordinate POC patient testing and facilitate compliance with procedures and
policies and regulatory requirements.

Answer 47

POCT coordinator (POCC)

Question 48

ensures the
electronics of the device are performing as expected or, if a manual test, the
integrity of the specific test system.

Answer 48

Internal QC

Question 49

onboard QC, internal checks, electronic QC, or intelligent QC

Answer 49

Internal QC

Question 50

The greatest source of error in POCT

Answer 50

Preanalytical error

Question 51

Preventing postanalytic errors in reporting can be achieved more reliably
with _______.

Answer 51

connectivity

Question 52

Reflectance
Electrochemistry, electrical impedance
Light scattering/optical motion
Immunoturbidimetry
Lateral flow, flow-through, or solid phase immunoassays
Spectrophotometry, multiwavelength spectrophotometry
Fluorescence, time-resolved fluorescence
Polymerase chain reaction

Answer 52

analytical principles

used in a laboratory have also been implemented in POCT devices

Question 53

If QC has not
been performed as required and is unsatisfactory, the instrument does not allow
patient testing until corrective action has taken place.

Answer 53

QC lockout