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Steven Soldin. An accomplished violinist. A world traveler. A collector of fine art. A lover of literature, ballet, and music. And yes, a renowned clinical chemist in 3 areas — therapeutic drug monitoring, pediatrics, and endocrinology. Born in Johannesburg, his career has spanned from teaching poor South Africans towards a high school diploma to his current post as a senior scientist in the department of laboratory medicine at the National Institutes of Health. In this month's Inspiring Minds feature, readers have the opportunity to learn about this special person for whom "the arts and sciences dance together.

In a 2009 study in Clinical Chemistry, Dr. Erna Lenters and Dr. Robbert Slingerland evaluated eight different points of care instruments measuring hemoglobin A1c and came to the conclusion that six of the eight did not meet generally accepted analytical performance criteria.

MicroRNAs measured in blood samples are promising, minimally invasive biomarker candidates that have recently been the target of many case control studies. However, the influence of age and gender is confounding variables and MicroRNAs remain largely unknown.

The cover of the September 2014 issue of Clinical Chemistry tells it all: one million downloads! That's the number of Clinical Chemistry podcasts that have been downloaded since the feature was initiated in 2009. It's a relatively new feature in the 60 years of publication of the journal, and the word podcast itself is only been in the vernacular for about 10 years.

Analysis of circulating RNA in the plasma of pregnant women can be a powerful tool for noninvasive prenatal testing and research. However, unbiased and high throughput detection of circulating RNA in plasma is a technical challenge.

This is the September 2014 issue of Clinical Chemistry, Volume 60, Issue 9.

Performing measurements that are comparable over time and location and across assays is essential for insuring appropriate clinical and public health practice. One step toward achieving this goal is using assays that are traceable to a higher-order reference measurement system or harmonized by using internationally recognized procedures.

Analysis of Human Chorionic Gonadotropin or hCG is usually associated with monitoring or detecting pregnancy. It is also a protein tumor marker for some cancers. In males, hCG stimulates testosterone production and has the potential to be abused by athletes in an attempt to enhance performance in sports.

There are few scientific papers that do not include the use of the P value to evaluate the statistical significance of results. However, use of this statistic may be misleading, as noted by a recent paper by Regina Nuzzo in the journal Nature. That paper served as a basis for commentary with additional examples by Drs. Jim Boyd and Tom Annesley in the July 2014 issue of Clinical Chemistry.

Model of Human Hemoglobin. Imagine the days when theses and dissertations were required to be written in Latin. In his 1825 Commentatio de vera materiae sanguini purpureum colorem impertientis natura, Johann Friederich Engelhart proposed the molecular mass of hemoglobin to be an astonishingly large 16000 Daltons per iron. No respectable scientist of the time believed that molecules could be that large. We now know that hemoglobin has a mass of ~64000 Daltons, is the major oxygen-carrying component of blood, and can bind with glucose to form glycated hemoglobin (most commonly measured as Hb A1c). Because Hb A1c is routinely measured for diagnosing diabetes and prediabetes, as well as monitoring mean glycemia, it is important that Hb A1c results be reliable. But how well do existing Hb A1c assays perform? This month's issue of Clinical Chemistry contains the results from 2 studies of Hb A1c assay performance, plus an accompanying editorial that discusses both of the studies.

Chronic kidney disease is an important risk factor for cardiovascular morbidity and mortality. This risk is all the more important for patients undergoing hemodialysis. In the presence of clinical signs of an acute myocardial infarction, the universal definition includes the finding of a serum cardiac troponin concentration above the 99 percentile as defined by healthy individuals, together with time dependant changes in serum and troponin concentrations. But in contrast to individuals with normal kidney function the troponin concentrations in patients with chronic kidney disease, but no myocardial infarction, may already be at concentrations higher than the 99 percentile of a healthy population.

Central nervous system infections, including diseases like meningitis and encephalitis, are important public heath concerns across the globe, as they occur commonly and/or associated with high rates of mortality and morbidity. Measurement of biomarkers provide objective indicators of normal function or pathology, and can present information that may assist diagnosis, assessment of health condition, and evaluation of treatment safety and efficacy.

Early detection of acute myocardial infarction is crucial for deciding the course of treatment to preserve and prevent further damage to the myocardial tissue. During the last several years there has been a burgeoning interest in circulating microRNAs as potential novel biomarkers for acute myocardial infarction.

The universal definition of myocardial infarction requires both an increase in cardiac troponin concentrations and changes in values over serial measurements. However, exact criteria regarding the magnitude of change in troponin remain elusive. In the June 2014 issue of Clinical Chemistry, two studies on biological variation of serum troponins helped shed further light on the kinetics of this important cardiac marker.!

On the cover this month: "Chicago" Neon Sign. Each year the July cover highlights the location of the AACC's Annual Meeting and Clinical Lab Expo. It does not take much effort to identify this year's host city. The Chicago Theatre, built in 1921, was originally known as the Balaban and Katz Chicago Theatre. The preeminent theatre for nearly 50 years, this ornate but obsolete movie house closed in 1985. But it did not die. After a meticulous renovation, this 3600-seat, 7-story high icon with its 29-rank Wurlitzer theatre pipe organ regained prominence and is as popular today as it was nearly 100 years ago. Of course, there is more to Chicago than this one theatre. There are dozens of art galleries, 26 miles of lakefront, and the Magnificent Mile. But most importantly, this year Chicago is the home of cutting-edge science and the world's largest Clinical Lab Expo, which will provide you with all you need to make informed decisions about the future of your laboratory. See you in Chicago!