Merck Research Laboratories, Merck & Co., Inc., Kenilworth, NJ, USA.
Published: June 2016
AI Article Synopsis
Article Abstract
Aim: A traditional oral fatty acid challenge assesses absorption of triacylglycerol (TG) into the periphery through the intestines, but cannot distinguish the composition or source of fatty acid in the TG. Stable isotope-labeled tracers combined with LC-MRM can be used to identify and distinguish TG synthesized with dietary and stored fatty acids.
Results: Concentrations of three abundant TGs (52:2, 54:3 and 54:4) were monitored for incorporation of one or two (2)H11-oleate molecules per TG. This method was subjected to routine assay validation and meets typical requirements for an assay to be used to support clinical studies.
Conclusion: Calculations for the fractional appearance rate of TG in plasma are presented along with the intracellular enterocyte precursor pool for 12 study participants.
Mass spectrometry (MS) is the only instrumental analytical technology that utilizes unique properties of matter, that is, its mass () and electrical charge (). In the magnetic and/or electric fields of mass spectrometers, electrically charged native or chemically modified (millions) endogenous and (thousands) exogenous substances, the analytes, are separated according to their characteristic mass-to-charge ratio (/) values. Mass spectrometers coupled to gas chromatographs (GC) or liquid chromatographs (LC), the so-called hyphenated techniques, i.
L-arginine: glycine amidinotransferase (AGAT) gained academic interest as the rate-limiting enzyme in creatine biosynthesis and its role in the regulation of creatine homeostasis. Of clinical relevance is the diagnosis of patients with AGAT deficiency but also the potential role of AGAT as therapeutic target for the treatment of another creatine deficiency syndrome, guanidinoacetate N-methyltransferase (GAMT) deficiency. Applying a stable isotope-labeled substrate method, we utilized ARG 15N (ARG-δ2) and GLY 13C15N (GLY-δ3) to determine the rate of 1,2-13C,15N guanidinoacetate (GAA-δ5) formation to assess AGAT activity in various mouse tissue samples and human-derived cells.
CAS Key Laboratory of Urban Pollutant Conversion, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Electronic address:
Bacteria play a crucial role in biodegradation of recalcitrant endocrine-disrupting compounds (EDCs), such as bisphenol A (BPA). However, in-situ identification of BPA-degrading bacteria remains technically challenging. Herein, we employed a conventional plating isolation (PI) and a new single cell Raman spectroscopy coupled with stable isotope probing (Raman-SIP) approach to enrich and identify BPA-degrading bacteria from activated sludge (AS).
CKD is frequently diagnosed only after a significant progression. GFR is the most common indicator of kidney function but is limited in detecting early CKD cases and distinguishing glomerular, tubular, and global CKD. Aiming to provide a glomeruli specific biomarker assay, we developed a peptide immunoaffinity targeted mass spectrometry method for the quantitation of three podocyte specific proteins in human urine: nephrin, podocalyxin, and podocin.
HAB Monitoring & Reference Branch, Stressor Detection and Impacts Division, National Centers for Coastal Ocean Science, NOAA National Ocean Service, 331 Fort Johnson Road, Charleston, SC, 29412, USA.
Background: Microcystins (MCs) and nodularins (NODs) produced by cyanobacteria occur in ambient freshwaters and across the freshwater-marine continuum, and pose health threats through drinking and recreational waters, as well as food resources. Approximately 300 MC and NOD toxins have been published, but less than 15 of them are commercially available as toxin standards. Our aim herein was to rapidly identify and quantify all toxin congeners, including those without standards, in water samples even at low abundance by reversed-phase solid phase extraction (SPE)-liquid chromatography-tandem mass spectrometry (LC-MS/MS) to provide insights into toxin levels and potential toxicity.
