UNLABELLED Quantitative nuclear renography has numerous potential sources of error. We previously reported the initial development of a computer software module for comprehensively addressing the issue of quality control (QC) in the analysis of radionuclide renal images. The objective of this study was to prospectively test the QC software. METHODS The QC software works in conjunction with st...

BACKGROUND Recent US practice guidelines and laboratory regulations for quality control (QC) emphasize the development of QC plans and the application of risk management principles. The US Clinical Laboratory Improvement Amendments (CLIA) now includes an option to comply with QC regulations by developing an individualized QC plan (IQCP) based on a risk assessment of the total testing process. T...

Brains of Alzheimer's disease (AD) patients are characterized in part by the formation of high molecular weight aggregates of amyloid-β (Aβ) peptides, which interfere with neuronal function and provoke neuronal cell death. The pyroglutamate (pGlu) modification of Aβ was demonstrated to be catalyzed by the enzyme glutaminyl cyclase (QC) and to enhance pathogenicity and neurotoxicity. Here, we ad...

Glutaminyl cyclases (QCs) from mammals and Drosophila are zinc-dependent enzymes that catalyze N-terminal pyroglutamate formation of numerous proteins and peptides. These enzymes have been found to be critical for the oviposition and embryogenesis of ticks, implying that they are possible physiological targets for tick control. Here, 1.10-1.15 Å resolution structures of a metal-independent QC f...

From the prescription to the delivery of a radiotherapy treatment, a team of professionals from a number of disciplines is involved. In this way significant potential for errors leading to an accidental exposure becomes apparent. Comprehensive quality assurance/quality control (QA/QC) program to minimize such errors is, therefore, required. One aspect of QA/QC program is quality control of the ...

Embedded within the meristem of all Angiosperm roots is a population of slowly dividing cells designated the quiescent center (QC). In maize roots the QC can constitute upwards of 800-1200 cells, most of which spend an extended period of time (180-200 hours) in the G(1) phase of the cell cycle. How the QC forms and is maintained is not known. Here we report that cells of the QC are characterize...

This study aimed to evaluate in silico models based on quantum chemical (QC) descriptors derived using the electronegativity equalization method (EEM) and to assess the use of QC properties to predict chemical metabolism by human UDP-glucuronosyltransferase (UGT) isoforms. Various EEM-derived QC molecular descriptors were calculated for known UGT substrates and nonsubstrates. Classification mod...

Abbreviations: LLOQ: Lower Limit of Quantification; QC: Quality Control; LQC: Low QC; MQC: Middle QC; HQC: High QC; SPE: Solid Phase Extraction; MRM: Multiple Reaction Monitoring; CV: Coefficient of Variation; RE: Relative Error; QqTOF: Quadrupole-QuadrupoleTime-Of-Flight; FDA: Food and Drug Administration; EMA: European Medicines Agency; XIC: Extracted-Ion Chromatogram; AUC: Area under the Cur...

OBJECTIVE We compared variations among Canadian provinces in rheumatoid arthritis (RA) initiating anti-tumor necrosis factor (TNF) therapy. METHODS Data were obtained from the Optimization of Humira trial (OH) and from the Ontario Biologics Research Initiative (OBRI). Baseline characteristics were compared between regions: Ontario (ON), Quebec (QC), and other provinces (OTH). We compared Onta...