A blood specimen is received in the laboratory for a PCR assay to detect cytomegalovirus (a DNA virus) on a Wednesday night. The PCR assay will not be performed until the next Monday morning. How should this specimen be stored to maintain the integrity of the nucleic acid prior to analysis?
What is Centrifuge to remove RBCs and store at -20o
100
Which of the following controls defines the lower limit of detection of a molecular target?
What is sensitivity
100
Whole blood was sent to the laboratory for viral load determination of HIV (an RNA virus). It was received on a Saturday morning, and the technologist working in the receiving section of the laboratory put the tube in the refrigerator at 2o-8oC. The molecular technologist came on Monday morning and collected the specimens that had been sent to the laboratory over the weekend. How should this sample be handled on Monday morning?
What is Call the nursing unit to ask that the blood be redrawn.
100
Controls run in a capillary gel electrophoresis instrument have been consistently not acceptable. It seems that the laser is not functioning properly and needs to be replaced. Which of the following is the correct course of action for the technologist in charge of this piece of equipment?
What is request a service visit from the manufacturer's technical support team who can replace the old laser with a new laser.
100
The sequence of amino acids in a protein constitutes which level of protein structure?
What is primary
200
An outbreak of Salmonella has occurred in the community. Molecular-based assays need to be performed in order to determine if all the Salmonella isolated at hospital X are related to each other and part of the outbreak. Laboratory technologists have accumulated 10 different cultures growing Salmonella and suspect that there may be more isolated in the next few days. The supervisor has asked that the molecular-based assays be performed on as many of the isolates as possible. How should these organisms be handled until the molecular-based assays can be performed in about 3 days?
What is Isolate DNA from all organisms and store at -20oC
200
Which of the following controls can distinguish between a true-negative in a nucleic acid amplification assay from a false-negative in which amplification failed in the specimen?
What is amplification
200
A technologist in a tissue bank who performed HLA typing by DNA analysis was asked to bank all DNA extracted from specimens received in the laboratory so as to maintain the highest quality of nucleic acid for the longest period. How should the DNA be stored to satisfy this request?
What is Freeze-dried at 22o-25oC
200
A woman calls and asks that the results of her husband's HIV viral load assay be faxed to her. She gives the technologist her husband's name and medical record number along with the date the specimen was collected and her fax number. She states that she is calling for her husband and has his approval. Which of the following is the correct course of action for the technologist?
What is Tell the woman that her husband can get his test results from his physician.
200
The chemical nature of alanine, leucine, phenylalanine, and tryptophan is described as:
What is nonpolar
300
A quantitative method was performed 100 times, and results from 99 of the 100 runs were in agreement with each other. This method has 99%:
What is precision
300
The temperature in a refrigerator that is used to store patient specimens and reagents should be checked how often?
What is daily
300
An assay that detects an analyte associated with a particular disease only in patients who have that disease and not in patients who do not have the disease has which of the following?
What is clinical specificity
300
An automated pipetting device has stopped working. Which of the following describes the best course of action for the technologist using this pipet?
What is Change or charge the batteries.
300
DNA replication proceeds with the new daughter strand synthesized in the following orientation:
What is 5' to 3'
400
The ability of a molecular-based assay to detect only the analyte and not other targets is called which of the following?
What is Analytic Specificity
400
The delivery of accurate voltage and current by an electrophoresis power supply should be checked how often?
What is Yearly
400
Which of the following does not have to be documented in a procedure description that is written according to CLSI guidelines?
What is Credentials of technologist performing the assay
400
In order to depurinate DNA after electrophoresis, the gel should be soaked in which of the following?
What is HCl
400
In the lactose operon, which of the following configurations would result in gene expression?
What is Promoter +, Operator +, Repressor -, no inducer present
500
Which of the following organizations has established standards used by laboratory professionals when developing, implementing, and performing molecular-based laboratory tests?
What is CLSI
500
Which of the following organizations provides oversight and governs the use the radioactive materials in the clinical laboratory?
What is nuclear regulatory commission
500
Credentials of technologist performing the assay
What is proficiency
500
hich of the following is not a method of transferring DNA from a gel to a membrane substrate?
What is Ionic
500
Which of the following is the binding site for the repressor protein of the lactose operon?