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https://www.readbyqxmd.com/read/28515163/assessment-of-nitric-oxide-production-in-mitochondrial-encephalomyopathy-lactic-acidosis-and-stroke-like-episodes-syndrome-with-the-use-of-a-stable-isotope-tracer-infusion-technique
#1
REVIEW
Ayman W El-Hattab, Farook Jahoor
Mitochondrial disorders result from dysfunctional mitochondria that are unable to generate sufficient energy to meet the needs of various organs. Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the most frequent maternally inherited mitochondrial disorders. There is growing evidence that nitric oxide (NO) deficiency occurs in MELAS syndrome and results in impaired blood perfusion that contributes significantly to several complications in this disease. NO is synthesized from arginine by NO synthase, which catalyzes the conversion of arginine to NO and citrulline...
May 17, 2017: Journal of Nutrition
https://www.readbyqxmd.com/read/28467082/novel-method-for-nitrogen-isotopic-analysis-of-soil-emitted-nitric-oxide
#2
Zhongjie Yu, Emily M Elliott
The global inventory of NOx (NOx = NO + NO2) emissions is poorly constrained, with a large portion of the uncertainty attributed to soil NO emissions that result from soil abiotic and microbial processes. While natural abundance stable N isotopes (δ(15)N) in various soil N-containing compounds have proven to be a robust tracer of soil N cycling, soil δ(15)N-NO is rarely quantified due to the measurement difficulties. Here, we present a new method that collects soil-emitted NO through NO conversion to NO2 in excess ozone (O3) and subsequent NO2 collection in a 20% triethanolamine (TEA) solution as nitrite and nitrate for δ(15)N analysis using the denitrifier method...
May 12, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28458168/a-rapid-method-for-estimation-of-pu-isotopes-in-urine-samples-using-high-volume-centrifuge
#3
Ranjeet Kumar, D D Rao, Rupali Dubla, J R Yadav
The conventional radio-analytical technique used for estimation of Pu-isotopes in urine samples involves anion exchange/TEVA column separation followed by alpha spectrometry. This sequence of analysis consumes nearly 3-4 days for completion. Many a times excreta analysis results are required urgently, particularly under repeat and incidental/emergency situations. Therefore, there is need to reduce the analysis time for the estimation of Pu-isotopes in bioassay samples. This paper gives the details of standardization of a rapid method for estimation of Pu-isotopes in urine samples using multi-purpose centrifuge, TEVA resin followed by alpha spectrometry...
April 20, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28424261/zinc-absorption-from-milk-is-affected-by-dilution-but-not-by-thermal-processing-and-milk-enhances-absorption-of-zinc-from-high-phytate-rice-in-young-dutch-women
#4
Elise F Talsma, Diego Moretti, Sou Chheng Ly, Renske Dekkers, Ellen Ghm van den Heuvel, Aditia Fitri, Esther Boelsma, Tjeerd Jan Stomph, Christophe Zeder, Alida Melse-Boonstra
Background: Milk has been suggested to increase zinc absorption. The effect of processing and the ability of milk to enhance zinc absorption from other foods has not been measured directly in humans.Objective: We aimed to assess zinc absorption from 1) milk undergoing various processing and preparatory steps and 2) from intrinsically labeled high-phytate rice consumed with milk or water.Methods: Two randomized crossover studies were conducted in healthy young women [age:18-25 y; body mass index (in kg/m(2)): 20-25]: 1) a milk study (n = 19) comparing the consumption of 800 mL full-fat ultra-high temperature (UHT) milk [heat-treated milk (HTM)], full-fat UHT milk diluted 1:1 with water [heat-treated milk and water (MW)], water, or unprocessed (raw) milk (UM), each extrinsically labeled with (67)Zn, and 2) a rice study (n = 18) comparing the consumption of 90 g intrinsically (67)Zn-labeled rice with 600 mL of water [rice and water (RW)] or full-fat UHT milk [rice and milk (RM)]...
April 19, 2017: Journal of Nutrition
https://www.readbyqxmd.com/read/28412769/applicability-of-geochemical-techniques-and-artificial-sweeteners-in-discriminating-the-anthropogenic-sources-of-chloride-in-shallow-groundwater-north-of-toronto-canada
#5
Esmaeil Khazaei, William Milne-Home
Elevated levels of chloride concentration due to anthropogenic activities including the road salts, septic effluent and agricultural sources are common in shallow groundwater of the recent glacial deposits north of Toronto, Ontario, Canada. Identifying suitable techniques for discriminating the source of the chloride concentration helps to better plan the protection of groundwater in the area. This paper examines the applicability of geochemical techniques with emphasis on Panno et al. (Ground Water 44: 176-187, 2006) and Mullaney et al...
May 2017: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/28402627/strategy-for-the-quantitation-of-a-protein-conjugate-via-hybrid-immunocapture-liquid-chromatography-with-sequential-hrms-and-srm-based-lc-ms-ms-analyses
#6
Yue Zhao, Guowen Liu, Xiling Yuan, Jinping Gan, Jon E Peterson, Jim X Shen
With the development of modern instrumentation and technologies, mass spectrometry based assays have played an important role in protein bioanalysis. We have developed a novel strategy by combining the "bottom-up" and "top-down" approaches using both high-resolution (HRMS) and selected reaction monitoring (SRM) based mass spectrometric detection to quantify a positron emission tomography (PET) detection tracer for an oncology marker. Monkey plasma samples were processed by immunocapture purification, followed by liquid chromatography (LC) with HRMS full scan analysis...
April 21, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28399577/drug-development-concepts-as-guides-for-optimizing-clinical-trials-of-supplemental-zinc-for-populations-at-risk-of-deficiency-or-diarrhea
#7
David H Alpers, Graeme P Young, Cuong D Tran, Elissa K Mortimer, Geetha L Gopalsamy, Nancy F Krebs, Mark J Manary, Balakrishnan S Ramakrishna, Henry J Binder, Ian L Brown, Leland V Miller
Studies on the efficacy of zinc supplementation for treatment or prevention of diarrhea have shown an inconsistent effect in populations at risk for zinc deficiency. Unlike drugs, which have no preexisting presence in the body, endogenous zinc must be assessed pharmacokinetically by isotope tracer studies. Although such methods have produced much data, very few studies have estimated the dose and the timing of dosing of zinc supplementation. This review examines drug kinetics used to establish the best dose, the timing of such doses, and the mechanism of action through pharmacodynamic markers and applies them, where possible, to zinc supplements...
March 1, 2017: Nutrition Reviews
https://www.readbyqxmd.com/read/28363095/microwave-assisted-solvothermal-synthesis-of-hierarchical-tio2-microspheres-for-efficient-electro-field-assisted-photocatalytic-removal-of-tributyltin-in-tannery-wastewater
#8
Yang Zhao, Zhiding Huang, Wenkai Chang, Chao Wei, Xugen Feng, Lin Ma, Xiaoxia Qi, Zenghe Li
Organotin compounds have been widely used in recent decades, however, the residential tributyltin (TBT) in environment has potential harmful effects on human health due to the disruption of endocrine system even at trace level. Herein, this work reports on an effective electro-field-assisted-photocatalytic technique for removal of TBT by applying an electric field to photocatalysis of as-prepared hierarchical TiO2 microspheres. The synthesis of catalytic materials is based on a self-assembly process induced by microwave-assisted solvothermal reaction...
July 2017: Chemosphere
https://www.readbyqxmd.com/read/28302981/studies-on-isotope-ratio-measurement-of-cl-by-inductively-coupled-plasma-triple-quad-mass-spectrometry
#9
Masaki Ohata, Yanbei Zhu, Naoko Nonose
Fundamental studies on isotope ratio measurement of Cl were carried out using inductively coupled plasma triple-quad mass spectrometry (ICP-MS/MS) and the analytical performance obtained was compared to that obtained by ICP sector field mass spectrometer (ICP-SFMS). Though the polyatomic ion interferences of (16)O(18)O(1)H and (36)Ar(1)H with respect to (35)Cl and (37)Cl, respectively, made a negative effect on the accuracy and the precision for isotope ratio measurements of Cl, the ICP-SFMS could eliminate these interferences by medium mass resolution mode (m/Δm = 4000) and achieved the isotope ratio measurements with 0...
2017: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
https://www.readbyqxmd.com/read/28289709/imaging-mass-spectrometry-demonstrates-age-related-decline-in-human-adipose-plasticity
#10
Christelle Guillermier, Pouneh K Fazeli, Soomin Kim, Mingyue Lun, Jonah P Zuflacht, Jessica Milian, Hang Lee, Hugues Francois-Saint-Cyr, Francois Horreard, David Larson, Evan D Rosen, Richard T Lee, Claude P Lechene, Matthew L Steinhauser
Quantification of stable isotope tracers has revealed the dynamic state of living tissues. A new form of imaging mass spectrometry quantifies isotope ratios in domains much smaller than a cubic micron, enabling measurement of cell turnover and metabolism with stable isotope tracers at the single-cell level with a methodology we refer to as multi-isotope imaging mass spectrometry. In a first-in-human study, we utilize stable isotope tracers of DNA synthesis and de novo lipogenesis to prospectively measure cell birth and adipocyte lipid turnover...
March 9, 2017: JCI Insight
https://www.readbyqxmd.com/read/28285086/rapid-determination-of-radium-224-226-in-seawater-sample-by-alpha-spectrometry
#11
Lijuan Song, Yonggang Yang, Maoyi Luo, Yan Ma, Xiongxin Dai
A new radiochemical separation method has been developed for rapid determination of alpha-emitting radium isotopes in seawater samples. This method can be applied for the measurement of (226)Ra in seawater samples when (224)Ra is used as tracer for chemical recovery correction. Likewise, (226)Ra can also be added as tracer for the determination of (224)Ra in seawater sample. In the method, radium is first pre-concentrated with hydrous titanium oxide (HTiO) and is purified by combined anion/cation exchange column chromatographic separation...
May 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28255355/hybrid-imaging-labels-providing-the-link-between-mass-spectrometry-based-molecular-pathology-and-theranostics
#12
Tessa Buckle, Steffen van der Wal, Stijn J M van Malderen, Larissa Müller, Joeri Kuil, Vincent van Unen, Ruud J B Peters, Margaretha E M van Bemmel, Liam A McDonnell, Aldrik H Velders, Frits Koning, Frank Vanhaeke, Fijs W B van Leeuwen
BACKGROUND: Development of theranostic concepts that include inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS) imaging can be hindered by the lack of a direct comparison to more standardly used methods for in vitro and in vivo evaluation; e.g. fluorescence or nuclear medicine. In this study a bimodal (or rather, hybrid) tracer that contains both a fluorescent dye and a chelate was used to evaluate the existence of a direct link between mass spectrometry (MS) and in vitro and in vivo molecular imaging findings using fluorescence and radioisotopes...
2017: Theranostics
https://www.readbyqxmd.com/read/28249106/rapid-quantification-and-isotopic-analysis-of-dissolved-sulfur-species
#13
Derek A Smith, Alex L Sessions, Katherine S Dawson, Nathan Dalleska, Victoria J Orphan
RATIONALE: Dissolved sulfur species are of significant interest, both as important substrates for microbial activities and as key intermediaries in biogeochemical cycles. Species of intermediate oxidation state such as sulfite, thiosulfate, and thiols are of particular interest but are notoriously difficult to analyze, because of low concentrations and rapid oxidation during storage and analysis. METHODS: Dissolved sulfur species are reacted with monobromobimane which yields a fluorescent bimane derivative that is stable to oxidation...
May 15, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28213127/quantitation-of-lead-210-210-pb-using-lead-203-203-pb-as-a-massless-yield-tracer
#14
D May, A N Nelson, M K Schultz
Determination of Pb-210 ((210)Pb) in aqueous solution is a common radioanalytical challenge in environmental science. Widely used methods for undertaking these analyses (e.g., ASTM D7535) rely on the use of stable lead (Pb) as a yield tracer that takes into account losses of (210)Pb that inevitably occur during elemental/radiochemical separations of the procedures. Although effective, these methods introduce technical challenges that can be difficult to track and potentially introduce uncertainty that can be difficult to quantify...
May 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28196754/determination-of-groundwater-recharge-mechanism-in-the-deep-loessial-unsaturated-zone-by-environmental-tracers
#15
Zhi Li, Xi Chen, Wenzhao Liu, Bingcheng Si
Studying the groundwater recharge mechanism in regions with thick unsaturated zone can greatly improve our understanding of hydrological processes since these regions have complex groundwater processes. This study attempted to discuss the groundwater recharge in a region covered by loess over 130m deep in China's Loess Plateau. The water stable isotope, tritium and chloride in precipitation, groundwater and soil water were determined and used as inputs of mass balance methods. The tracer technique is found to be applicable and effective this region with thick unsaturated zone...
May 15, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28195703/mass-spectrometric-determination-of-uranium-and-thorium-in-high-radiopurity-polymers-using-ultra-low-background-electroformed-copper-crucibles-for-dry-ashing
#16
Isaac J Arnquist, Eric J Hoppe, Mary Bliss, Jay W Grate
A rapid new method for determining the U and Th mass concentrations in high radiopurity plastics is described, consisting of (1) dry ashing the plastic sample and tracers in low mass crucibles made of ultra low background electroformed copper (ULB EF-Cu) foil cut and folded into boats, (2) dissolving both the ash and the boat in acid, (3) performing a column separation to remove copper, and (4) determining the elements of interest by isotope dilution mass spectrometry. This method was demonstrated on both unfluorinated and fluorinated plastics, demonstrating high tracer recoveries and detection limits to pg/g (i...
February 24, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28192957/integrated-extraction-chromatographic-separation-of-the-lithophile-elements-involved-in-long-lived-radiogenic-isotope-systems-rb-sr-u-th-pb-sm-nd-la-ce-and-lu-hf-useful-in-geochemical-and-environmental-sciences
#17
Christian Pin, Abdelmouhcine Gannoun
A fast and efficient sample preparation method in view of isotope ratio measurements is described, allowing the separation of 11 elements involved, either as "parent" or as "daughter" isotopes, in six radiogenic isotope systems used as chronometers and tracers in earth, planetary, and environmental sciences. The protocol is based on small extraction chromatographic columns, used either alone or in tandem, through which a single nitric acid solution is passed, without any intervening evaporation step. The columns use commercially available extraction resins (Sr resin, TRU resin, Ln resin, RE resin, and again Ln resin for isolating Sr and Pb, LREE then La-Ce-Nd-Sm, Lu(Yb), and Hf, Th, and U, respectively) along with an additional, in-house prepared resin for separating Rb...
February 9, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28168704/positron-emission-tomography-with-additional-%C3%AE-ray-detectors-for-multiple-tracer-imaging
#18
Tomonori Fukuchi, Takashi Okauchi, Mika Shigeta, Seiichi Yamamoto, Yasuyoshi Watanabe, Shuichi Enomoto
PURPOSE: Positron emission tomography (PET) is a useful imaging modality that quantifies the physiological distributions of radiolabeled tracers in vivo in humans and animals. However, this technique is unsuitable for multiple-tracer imaging because the annihilation photons used for PET imaging have a fixed energy regardless of the selection of the radionuclide tracer. This study developed a multi-isotope PET (MI-PET) system and evaluated its imaging performance. METHODS: Our MI-PET system is composed of a PET system and additional γ-ray detectors...
February 7, 2017: Medical Physics
https://www.readbyqxmd.com/read/28161269/the-simultaneous-uptake-of-dietary-and-waterborne-cd-in-gastrointestinal-tracts-of-marine-yellowstripe-goby-mugilogobius-chulae
#19
Zhiqiang Guo, Na Gao, Yun Wu, Li Zhang
Aquatic animals under waterborne metal exposure are also very likely exposed to elevated dietary metals. This study quantified the simultaneous uptake of dietary and waterborne Cd in gastrointestinal tracts (GT) of marine yellowstripe goby using a dual stable isotope tracer method. The Cd spiked diet (10-100 μg g(-1), (111)Cd as tracers) were fed to the fish as a single meal, and then the fish were exposed to waterborne Cd (0-500 μg L(-1), (113)Cd as tracers) for 48 h, during which the time-course uptake of Cd in the stomach and intestine was determined...
April 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28158972/midcor-an-r-program-for-deciphering-mass-interferences-in-mass-spectra-of-metabolites-enriched-in-stable-isotopes
#20
Vitaly A Selivanov, Adrián Benito, Anibal Miranda, Esther Aguilar, Ibrahim Halil Polat, Josep J Centelles, Anusha Jayaraman, Paul W N Lee, Silvia Marin, Marta Cascante
BACKGROUND: Tracing stable isotopes, such as (13)C using various mass spectrometry (MS) methods provides a valuable information necessary for the study of biochemical processes in cells. However, extracting such information requires special care, such as a correction for naturally occurring isotopes, or overlapping mass spectra of various components of the cell culture medium. Developing a method for a correction of overlapping peaks is the primary objective of this study. RESULTS: Our computer program-MIDcor (free at https://github...
February 3, 2017: BMC Bioinformatics
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