Demographic and socioeconomic trends in DNA banking utilization in the USA.

Demographic and clinical information from de-identified individuals utilizing a single DNA banking service over a 22-year period was assessed using descriptive statistics. The socioeconomic characteristics of the study population were estimated using a zip code-level analysis of US Census data and compared to national US Metrics for 2016. Samples from 4,874 individuals were deposited to a single commercial DNA bank from 1997 to 2019.

A validated surrogate analyte LC-MS/MS assay for quantitation of endogenous kynurenine and tryptophan in human plasma.

Aim: Indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) catalyze the initial and rate-controlling step of tryptophan metabolism through the kynurenine pathway, which plays an important role in mediating immune response. Accurate measurement of tryptophan and kynurenine is critical for monitoring the activity of IDO/TDO. Experimental: Surrogate analytes ([15N2]-Tryptophan and [13C6]-Kynurenine) were used for preparation of calibration standard and quality control.

Development of a multi-matrix LC-MS/MS method for urea quantitation and its application in human respiratory disease studies.

In human respiratory disease studies, liquid samples such as nasal secretion (NS), lung epithelial lining fluid (ELF), or upper airway mucosal lining fluid (MLF) are frequently collected, but their volumes often remain unknown. The lack of volume information makes it hard to estimate the actual concentration of recovered active pharmaceutical ingredient or biomarkers. Urea has been proposed to serve as a sample volume marker because it can freely diffuse through most body compartments and is less affected by disease states.

Validation and determination of taselisib, a β-sparing phosphoinositide 3-kinase (PI3K) inhibitor, in human plasma by LC-MS/MS.

A liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method for the determination of taselisib (GDC-0032, RO5537381) concentrations in human plasma has been developed and validated to support bioanalysis of clinical samples. Solid phase extraction (SPE) was used to extract plasma samples (50μL) and the resulting samples were analyzed using reversed phase chromatography and mass spectrometry coupled with an atmospheric pressure chemical ionization interface. The mass analysis of taselisib was performed using multiple reaction monitoring transitions in positive ionization mode.