The elevation in the concentrations of prostate-specific antigen, or PSA, in blood after prostatectomy is the only available marker from monitoring relapse after surgery. This increase in PSA is sometimes called biochemical failure or biochemical relapse. PSA monitoring, however, cannot predict relapse at the time of surgery.

On the cover this month: Francis Crick's original sketch of the structure of DNA.

Drawn on a scrap of A4 paper, this image provided the first look at the doublehelix

structure of DNA. It is important to remember that 60 years ago there were

no software programs for drawing structures, and neither Francis Crick nor James

Watson had any artistic talent. Francis Crick asked his wife Odile, an

accomplished artist, to abandon her painting and illustrate her husband's work.

It was Odile's exquisite and iconic drawing of the double helix that was included

in their 1953 research study that was submitted to Nature. Not only that, it was

James Watson's sister Betty who typed the historic paper. It makes one wonder

how Crick and Watson would have fared without the help of two women, Odile

Crick and Betty Watson. Skipping ahead 60 years, this month's issue of Clinical

Chemistry contains what we believe is an important research study and

accompanying editorial describing maternal plasma DNA bisulfite sequencing for

noninvasive prenatal testing.

New diagnostics technologies such as microarrays, next generation, or massively parallel sequencing, are generating an unprecedented amount of data. This requires a sophisticated knowledge of bioinformatics for proper storage, analysis, and mining of these very large data sets.

The application of Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry or MALDI-TOF MS, to microbial identification is revolutionizing clinical microbiology, providing rapid identification with minimal sample preparation and potential cost savings.

And our guest today is Dr. Nader Rifai, Editor-in-Chief of Clinical Chemistry and Chair of the Clinical Chemistry Trainee Council, to announce the launch of a new program from AACC's Clinical Chemistry Trainee Council, the Question Bank. And Dr. Rifai, why was the Question Bank created?

The discovery phase of proteomics is critical in the identification of suitable markers for exploration and validation of promising new clinical tests. But can laboratories be certain if what they believe they are measuring is, in fact, what they actually measuring?

This is the October 2013 issue of Clinical Chemistry: Volume 59, Issue 10.

The analysis of circulating cell-free tumor DNA has considerable potential for the detention and monitoring of cancers. Substantial effort has been made to identify cancer associated genetic changes that might be suitable for use as new tumor markers. However, only a few of these genetic markers have been translated into clinical use.

The clinical microbiology laboratory is sometimes considered low-tech, particularly when compared to the high degree of automation found in the clinical chemistry laboratory. However, systems are emerging for the clinical microbiology laboratory with the potential to automate almost all areas of testing, including inoculation of primary culture plates, detection of growth on culture media, susceptibility testing, and extraction and detection of nucleic acids from clinical specimens.

For many taking a home pregnancy test can be upsetting, particularly if there is not complete confidence in the result. The November 2013 print issue of Clinical Chemistry published a paper from a group led by Dr. Ann Gronowski that reported false-negative results in point-of-care and over-the-counter qualitative hCG devices.