A Comparative Analysis of Two Commonly Used FDA-Approved Immunoassays for Fentanyl Detection.

Background: Given the opioid epidemic, fentanyl screening in urine has become increasingly important. Immunoassays remain the most common screening methodology due to the high throughput and ease of integration into automated chemistry systems. The fentanyl ARK II from Ark Diagnostics is a widely used immunoassay, while a novel fentanyl assay called FEN2 by Lin-Zhi has become available on the Roche platform.

Variable Delta-9-Tetrahydrocannabinol Pharmacokinetics and Pharmacodynamics After Cannabis Smoking in Regular Users.

Background: Despite its federally restricted status, cannabis is widely used medicinally and recreationally. The pharmacokinetics (PK) and central nervous system (CNS) effects of tetrahydrocannabinol (THC), the major psychoactive cannabinoid, are not well understood. The objective of this study was to develop a population PK model of inhaled THC, including sources of variability, and to conduct an exploratory analysis of potential exposure-response relationships.

Evaluating the performance of the Roche FEN2 fentanyl immunoassay and its clinical implementation: The role of LDT-based mass spectrometry testing.

Introduction: While laboratory-developed tests (LDTs) using liquid chromatography tandem mass spectrometry (LC-MS/MS) are widely employed to support the development of FDA-cleared drug immunoassays, their significance in the clinical implementation and evaluation of such assays is often overlooked. This paper reports on the important role of LC-MS/MS LDTs in demonstrating improved performance of the Roche FEN2 fentanyl immunoassay compared with the Thermo DRI fentanyl immunoassay.

Methods: The FEN2 assay was implemented according to the manufacturer's instructions and its performance was compared to the existing DRI assay using LC-MS/MS as a reference.

Digital Histological Study of Neocortical Grey and White Matter Tau Burden Across Tauopathies.

3R/4R-tau species are found in Alzheimer disease (AD) and ∼50% of Lewy body dementias at autopsy (LBD+tau); 4R-tau accumulations are found in progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Digital image analysis techniques can elucidate patterns of tau pathology more precisely than traditional methods but repeatability across centers is unclear. We calculated regional percentage areas occupied by tau pathological inclusions from the middle frontal cortex (MFC), superior temporal cortex (STC), and angular gyrus (ANG) from cases from the University of Pennsylvania and the University of California San Diego with AD, LBD+tau, PSP, or CBD (n = 150) using QuPath.

A User-Friendly Sample Preparation Alternative for Manual and Automated LC-MS/MS Quantification of Testosterone.

We describe an LC-MS/MS method for serum testosterone using a novel extraction media, AC Extraction Plate™ (AC Plate,Tecan Schweiz). The AC Plate principle is essentially that of a liquid-liquid extraction (LLE) but employs a stationary nonpolar phase coated on the wells of 96-well plates instead of a nonmiscible organic solvent for partitioning testosterone out of serum, leaving interfering substances behind. This low complexity sample preparation protocol has been validated for and used in production in our laboratory with both manual and automated liquid handling.

Qua-Alluding to the Past: A Case of Methaqualone Analog Ingestion.

Methaqualone, known previously under the brand name Quaalude, is a Schedule I sedative hypnotic drug that may cause neurotoxicity in overdose, characterized by somnolence, hyperreflexia and muscular hyperactivity. We present a case of a 21-year-old male who reportedly ingested methaqualone in addition to insufflation of street cocaine. He subsequently developed hypoxia, hyperreflexia, myoclonus, and altered mental status.

Transcriptional processing of an unnatural base pair by eukaryotic RNA polymerase II.

The development of unnatural base pairs (UBPs) has greatly increased the information storage capacity of DNA, allowing for transcription of unnatural RNA by the heterologously expressed T7 RNA polymerase (RNAP) in Escherichia coli. However, little is known about how UBPs are transcribed by cellular RNA polymerases. Here, we investigated how synthetic unnatural nucleotides, NaM and TPT3, are recognized by eukaryotic RNA polymerase II (Pol II) and found that Pol II is able to selectively recognize UBPs with high fidelity when dTPT3 is in the template strand and rNaMTP acts as the nucleotide substrate.

Genetic testing strategies in the newborn.

Genetic disorders presenting in the neonatal period can have a significant impact on morbidity and mortality. Early diagnosis can facilitate timely prognostic counseling to families and possibility of precision care, which could improve outcome. As availability of diagnostic testing expands, the required knowledge base of the neonatologist must also expand to include proper application and understanding of genetic testing modalities, especially where availability of clinical genetics consultation is limited.

Metatranscriptomic identification of polyamine-transforming bacterioplankton in the Gulf of Mexico.

The importance of short-chained aliphatic polyamines (PAs) to bacterioplankton-mediated carbon and nitrogen cycles has been repeatedly proposed. However, bacterial taxa and genes involved in the transformations of different PA compounds and their potential spatial variations remain unclear. This study collected surface bacterioplankton from nearshore, offshore, and open ocean stations in the Gulf of Mexico and examined how metatranscriptomes responded to additions of three single PA model compounds (i.

Proteomic screening of plasma identifies potential noninvasive biomarkers associated with significant/advanced fibrosis in patients with nonalcoholic fatty liver disease.

Noninvasive biomarkers are clinically useful for evaluating liver fibrosis stage in patients with nonalcoholic fatty liver disease (NAFLD). The aim of the present study was to compare plasma proteins in patients with early nonalcoholic steatohepatitis (NASH) (F0-F1) versus NASH with significant/advanced fibrosis (F2-F4) to determine whether candidate proteins could be used as potential noninvasive biomarkers. Nineteen biopsy-proven NAFLD patients including ten early NASH patients and nine NASH patients with significant/advanced fibrosis were enrolled in the present study.

Annotation of Variant Data from High-Throughput DNA Sequencing from Tumor Specimens: Filtering Strategies to Identify Driver Mutations.

The use of next-generation sequencing technologies has enabled the analysis of a wide spectrum of somatic mutations in tumors. This analysis can be carried out using various strategies including the use of small panels of focused, clinically actionable genes, large panels of cancer-related genes, whole exomes, and the entire genome. One of the main goals in these analyses is to identify key mutations in these tumors that drive the oncogenic process.

Bioinformatics Basics for High-Throughput Hybridization-Based Targeted DNA Sequencing from FFPE-Derived Tumor Specimens: From Reads to Variants.

The use of next-generation sequencing and hybridization-based capture for target enrichment have enabled the interrogation of coding regions of several clinically significant cancer genes in tumor specimens using both targeted panels of a few to hundreds of genes, to whole-exome panels encompassing coding regions of all genes in the genome. Next-generation sequencing (NGS) technologies produce millions of relatively short segments of sequences or reads that require bioinformatics tools to map reads back to a reference genome using various read alignment tools, as well as to determine differences between single bases (single nucleotide variants or SNVs) or multiple bases (insertions and deletions or indels) between the aligned reads and the reference genome to call variants. In addition to single nucleotide changes or small insertions and deletions, high copy gains and losses can also be gleaned from NGS data to call gene amplifications and deletions.

Library Preparation Using FFPE-Derived Tumor DNA for High-Throughput Hybridization-Based Targeted or Exome Sequencing.

The use of next generation sequencing (NGS) to profile tumor genomes for the presence of diagnostic, prognostic, or therapeutically targetable variants is revolutionizing the practice of oncology and is increasingly utilized in clinical laboratory settings. Beginning with the isolation of DNA of sufficient quality and quantity from a tumor specimen, the creation of a library of genomic fragments representing the portion of the genome of interest, ranging from a few genes to the entire exome, is the first step required in the sequencing process. Fixed tumor tissue in the form of a tissue block is the most commonly encountered specimen for analysis in a clinical setting.

Validation of a liquid chromatography-tandem mass spectrometry method for analyzing cannabinoids in oral fluid.

A liquid chromatography tandem mass spectrometry method was developed for quantifying ten cannabinoids in oral fluid (OF). This method utilizes OF collected by the Quantisal™ device and concurrently quantifies cannabinol (CBN), cannabidiol (CBD), Δ-tetrahydrocannabinol (THC), 11-hydroxy-Δ-THC (11-OH-THC), 11-nor-9-carboxy-Δ-THC (THC-COOH), 11-nor-9-carboxy-Δ-THC glucuronide (THC-COOH-gluc), Δ-THC glucuronide (THC-gluc), cannabigerol (CBG), tetrahydrocannabiverin (THCV), and Δ-tetrahydrocannabinolic acid A (THCA-A). Solid phase extraction was optimized using Oasis Prime HLB 30 mg 96-well plates.

Comparison of four clinically validated testosterone LC-MS/MS assays: Harmonization is an attainable goal.

Introduction: Immunoassays and liquid chromatography-tandem mass spectrometry assays are commonly employed in clinical laboratories for measurement of total testosterone in serum. Results obtained from either of these methodologies compare poorly due to differences in calibration and/or inadvertent detection of interfering substances by the immunoassays. Standardization efforts are underway, but recent studies indicate that accuracy remains an issue.

Multicenter assessment of a hemoglobin A1c point-of-care device for diagnosis of diabetes mellitus.

Objective: A multisite investigation compared the analytical performance of a point-of-care (POC) HbA1c device with multiple commonly used HbA1c laboratory methods and an NGSP (National Glycohemoglobin Standardization Program) reference method.

Research Design And Methods: The Afinion AS100 POC device analyzed HbA1c using 618 EDTA whole blood excess patient specimens with clinically indicated HbA1c testing. Results were compared to measurements across five clinical laboratories and the NGSP reference method.

Liquid Chromatography-Mass Spectrometry Education for Clinical Laboratory Scientists.

This article describes the need for, stratifies the complexity of, and proposes detailed lists of training competencies for diagnostic laboratory personnel using quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) for patient care. Although quantitative LC-MS/MS is evolving toward greater automation with less need for technical expertise, gaps remain in resources for training and assessment.

Reproducibility assessment for a broad spectrum drug screening method from urine using liquid chromatography time-of-flight mass spectrometry.

During the reproducibility validation for a time-of-flight (TOF) high-resolution mass spectrometry (HRMS) method set up to detect 61 drugs of abuse commonly encountered in the toxicology laboratory, it was noticed that, a number of compounds were not identified correctly during the between run analysis; the most difficult compounds to identify were norpropoxyphene, morphine, norbuprenorphine, nortriptyline, EDDP and tramadol. In subsequent patient comparison studies, screening a panel of 338 analytes, the TOF-HRMS method correctly identified 211 analytes over two runs, but did not identify 127. A total of 11 false positive results were identified by manual review of the data to be the result of confirmation ion signal-to-noise ratio(s) < 3, although one false positive that was difficult to resolve (i.

Interpretation of Pain Management Testing Results Using Case Examples.

Background: Because of the increasing volume of opiate-related overdoses, clinical testing of urine for drugs and related compounds in pain management clinics has become increasingly important. Interpreting findings of drugs present in urine specimens requires knowledge of pharmacokinetics, metabolism, drug purity, and cutoff concentrations used to report a positive result.

Content: This case-based mini-review provides examples of how to interpret immunoassay and quantitative confirmatory urine drug-testing results.

Automated Sample Preparation Enables LC-MS/MS as a Routine Diagnostic Analysis for Serum Testosterone.

Background: The advantage of LC-MS/MS for analyzing serum testosterone in female, pediatric, and hypogonadal male patient samples is well accepted (J Clin Endocrinol Metab 2010;95:4542-8). However, many clinical laboratories still use testosterone immunoassays because of the technical challenges of LC-MS/MS (Clin Chem 2010;56:1234-44). Although LC-MS/MS has been shown to have better accuracy and specificity than immunoassay, better reproducibility has been more elusive because of the complexities of sample preparation (Clin Chem 2008;54:1290-7; Rev Endocr Metab Disord 2013;14:185-205).

Near death from a novel synthetic opioid labeled U-47700: emergence of a new opioid class.

Background: In the last decade there has been a worldwide surge in the recreational abuse of novel psychoactive substances, particularly amphetamine derivatives and synthetic cannabinoids. Synthetic opioids such as AH-7921, MT-45, and U-47700, with structures distinct from those ever used therapeutically or described recreationally, have also recently emerged.

Case Details: We report a patient who suffered respiratory failure and depressed level of consciousness after recreationally using a novel synthetic opioid labeled U-47700.