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https://www.readbyqxmd.com/read/28428694/a-microarray-immunoassay-for-serum-thyrotropin-and-thyroglobulin-using-antibodies-immobilized-on-track-etched-membranes
#1
Bharti Jain, J Kumarasamy, Chandrakala Gholve, Savita Kulkarni, M G R Rajan
Serum thyroglobulin (Tg) and thyroid stimulating hormone (TSH) measurements have evolved as important analytes for monitoring the prognosis of patients with differentiated thyroid cancer, post-thyroidectomy. Individual analyte immunoassay is the current practice in clinical pathology, but the simultaneous assay for all relevant analytes for a given disease, can reduce assay costs, improve patient compliance and give the clinician more information for an unequivocal diagnosis. Microarray immunoassay (MI) can achieve this goal and, hence, we have developed and validated a immuno-radiometric MI for quantitation of serum TSH and Tg by using highly micro-porous polycarbonate (PC) track-etched membranes (TEM) to immobilize the monoclonal anti-TSH and polyclonal anti-Tg antibodies in ~1 mm diameter spots...
June 2017: Indian Journal of Clinical Biochemistry: IJCB
https://www.readbyqxmd.com/read/28426983/constraining-the-temporal-variations-of-ra-isotopes-and-rn-in-the-groundwater-end-member-implications-for-derived-sgd-estimates
#2
Marc Cerdà-Domènech, Valentí Rodellas, Albert Folch, Jordi Garcia-Orellana
Submarine groundwater discharge (SGD) has been recognized as an important supplier of chemical compounds to the ocean that may influence coastal geochemical cycles. Radium isotopes ((223)Ra, (224)Ra, (226)Ra,(228)Ra) and radon ((222)Rn) have been widely applied as tracers of SGD. Their application requires the appropriate characterization of both the concentrations of tracers in the discharging groundwater and their distribution in the coastal water column. This study evaluates the temporal evolution of Ra isotopes and (222)Rn concentrations in a dynamic subterranean estuary of a microtidal Mediterranean coastal aquifer that experiences large displacements of the fresh-saltwater interface as a necessary initial step in evaluating the influence of SGD in coastal waters...
April 17, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28424373/statins-pcsk9-inhibitors-and-cholesterol-homeostasis-a-view-from-within-the-hepatocyte
#3
EDITORIAL
Allan D Sniderman, Robert Scott Kiss, Thomas Reid, George Thanassoulis, Gerald F Watts
Statins and PCSK9 inhibitors dramatically lower plasma LDL levels and dramatically increase LDL receptor number within hepatocyte cell membranes. It seems self-evident that total clearance of LDL particles from plasma and total delivery of cholesterol to the liver must increase in consequence. However, based on the results of stable isotope tracer studies, this analysis demonstrates the contrary to be the case. Statins do not change the production rate of LDL particles. Accordingly, at steady state, the clearance rate cannot change...
May 1, 2017: Clinical Science (1979-)
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/28403606/halogenated-organic-compounds-identified-in-hydraulic-fracturing-wastewaters-using-ultrahigh-resolution-mass-spectrometry
#6
Jenna Lynn Luek, Philippe Schmitt-Kopplin, Paula J Mouser, William Tyler Petty, Susan D Richardson, Michael Gonsior
Large volumes of water return to the surface following hydraulic fracturing of deep shale formations to retrieve oil and natural gas. Current understanding of the specific organic constituents in these hydraulic fracturing wastewaters is limited to hydrocarbons and a fraction of known chemical additives. In this study, we analyzed hydraulic fracturing wastewater samples using ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) as a non-targeted technique to assign unambiguous molecular formulas to singly charged molecular ions...
April 12, 2017: Environmental Science & Technology
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
#7
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
#8
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/28393905/metabolomic-characterisation-of-the-effects-of-oncogenic-pik3ca-transformation-in-a-breast-epithelial-cell-line
#9
Chung-Ho E Lau, Gregory D Tredwell, James K Ellis, Eric W-F Lam, Hector C Keun
Somatic mutations in PIK3CA are frequently found in a number of human cancers, including breast cancer, altering cellular physiology and tumour sensitivity to chemotherapy. This renders PIK3CA an attractive molecular target for early detection and personalised therapy. Using (1)H Nuclear Magnetic Resonance spectroscopy (NMR) and Gas Chromatography - Mass Spectrometery (GC-MS) together with (13)C stable isotope-labelled glucose and glutamine as metabolic tracers, we probed the phenotypic changes in metabolism following a single copy knock-in of mutant PIK3CA (H1047R) in the MCF10A cell line, an important cell model for studying oncogenic transformation in breast tissues...
April 10, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28392500/metabolism-and-proteomics-of-large-and-small-dense-ldl-in-combined-hyperlipidemia-effects-of-rosuvastatin
#10
Nuntakorn Thongtang, Margaret R Diffenderfer, Esther M M Ooi, P Hugh R Barrett, Scott M Turner, Ngoc-Anh Le, W Virgil Brown, Ernst J Schaefer
Small dense LDL (sdLDL) has been reported to be more atherogenic than large buoyant LDL (lbLDL). We examined the metabolism and protein composition of sdLDL and lbLDL in six subjects with combined hyperlipidemia on placebo and rosuvastatin 40 mg/day. ApoB-100 kinetics in triglyceride rich lipoproteins (TRL), lbLDL (density [d] 1.019-1.044 g/ml), and sdLDL (d 1.044-1.063 g/ml) were determined in the fed state using stable isotope tracers, mass spectrometry, and compartmental modeling. Compared with placebo, rosuvastatin decreased LDL cholesterol and apoB-100 levels in TRL, lbLDL, and sdLDL by significantly increasing the fractional catabolic rate of apoB-100 (TRL +45%; lbLDL +131%; sdLDL +97%), without a change in production...
April 9, 2017: Journal of Lipid Research
https://www.readbyqxmd.com/read/28390703/evaluation-of-mercury-methylation-and-methylmercury-demethylation-rates-in-vegetated-and-non-vegetated-saltmarsh-sediments-from-two-portuguese-estuaries
#11
Rute Cesário, Holger Hintelmann, Ricardo Mendes, Kevin Eckey, Brian Dimock, Beatriz Araújo, Ana Maria Mota, João Canário
Neurotoxic methylmercury (MMHg) is formed from inorganic divalent mercury (Hg(2+)). However, it is poorly understood to what extent different mercury (Hg) pools contribute to existent MMHg levels. In this study, ambient concentrations of total Hg (THg) and MMHg as well as rates of methylation and demethylation were measured simultaneously in sediments with and without salt-marsh plant vegetation, which were collected in Guadiana and Tagus estuaries, Portugal. Concurrent processes of Hg methylation and MMHg demethylation were directly monitored and compared by spiking sediments cores with stable isotope tracers of (199)Hg(2+) and CH3(201)Hg(+) followed by gas chromatographic separation and isotope-specific detection using inductively coupled plasma mass spectrometry...
April 5, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28370540/use-of-13-c-and-phosphate-18-o-labeled-substrate-for-studying-phosphorus-and-carbon-cycling-in-soils-a-proof-of-concept
#12
Avner Gross, Alon Angert
RATIONALE: Stable isotopes tracers are commonly used to track the transformations of organic carbon (C) and nitrogen (N) in soils but have not been used to follow coupled cycles of phosphorus (P) and C because P has only one stable isotope. METHODS: A novel dually labeled substrate composed of a (13) C-labeled glucose backbone attached to a phosphate group with known δ(18) OP value was used to follow the fate of C and P derived from the same compound. The tracer was amended to soils from two natural Oak forests and the δ(13) C values of respired CO2 and the δ(18) OP values of soil bioavailable P were measured...
March 30, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28369860/broad-shifts-in-the-resource-use-of-a-commercially-harvested-fish-following-the-invasion-of-dreissenid-mussels
#13
Shannon A Fera, Michael D Rennie, Erin S Dunlop
Dreissenid mussels -NDASH-including the zebra (Dreissena polymorpha) and quagga (Dreissena rostiformus bugensis) mussel-NDASH- are invasive species known for their capacity to act as ecosystem engineers. They have caused significant changes in the many freshwater systems they have invaded by increasing water clarity, reducing primary productivity, and altering zooplankton and benthic invertebrate assemblages. What is less clear is how their ecosystem engineering effects manifest up the food web to impact higher trophic levels, including fish...
April 2, 2017: Ecology
https://www.readbyqxmd.com/read/28369547/the-complex-character-of-photosynthesis-in-cucumber-fruit
#14
Xiaolei Sui, Nan Shan, Liping Hu, Cankui Zhang, Changqing Yu, Huazhong Ren, Robert Turgeon, Zhenxian Zhang
The surface area of a mature green cucumber (Cucumis sativa L.) fruit is comparable with that of a functional leaf, but the characteristics of fruit photosynthesis and its contribution to growth are poorly understood. Here, the photosynthetic properties of two genotypes of cucumber (dark green and light green fruits) were studied using a combination of electron microscopy, immunogold enzyme localization, chlorophyll fluorescence imaging, isotope tracer, and fruit darkening techniques. Chlorophyll content of the exocarp is similar to that of leaves, but there are no distinctive palisade and spongy tissues...
March 27, 2017: Journal of Experimental Botany
https://www.readbyqxmd.com/read/28368310/role-of-the-enterocyte-in-fructose-induced-hypertriglyceridaemia
#15
REVIEW
Simon Steenson, A Margot Umpleby, Julie A Lovegrove, Kim G Jackson, Barbara A Fielding
Dietary fructose has been linked to an increased post-prandial triglyceride (TG) level; which is an established independent risk factor for cardiovascular disease. Although much research has focused on the effects of fructose consumption on liver-derived very-low density lipoprotein (VLDL); emerging evidence also suggests that fructose may raise post-prandial TG levels by affecting the metabolism of enterocytes of the small intestine. Enterocytes have become well recognised for their ability to transiently store lipids following a meal and to thus control post-prandial TG levels according to the rate of chylomicron (CM) lipoprotein synthesis and secretion...
April 1, 2017: Nutrients
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
#16
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...
March 24, 2017: Chemosphere
https://www.readbyqxmd.com/read/28344366/mercury-in-feathers-and-blood-of-gulls-from-the-southern-baltic-coast-poland
#17
Emilia Szumiło-Pilarska, Lucyna Falkowska, Agnieszka Grajewska, Włodzimierz Meissner
Gulls were assessed as sentinels of contamination in the coastal zone of the Southern Baltic, research material being obtained from dead birds collected on Polish beaches and near fishing ports in 2009-2012. In feathers and blood of four gull species: herring gull (Larus argentatus), common gull (Larus canus), black-headed gull (Chroicocephalus ridibundus), and great black-backed gull (Larus marinus), concentration of total mercury (HgT) was assayed, taking into account the type of feathers, sex, and age. Stable isotopes (δ(15)N, δ(13)C) were used as tracers of trophic position in the food web...
2017: Water, Air, and Soil Pollution
https://www.readbyqxmd.com/read/28303165/modeling-framework-for-isotopic-labeling-of-heteronuclear-moieties
#18
Mark I Borkum, Patrick N Reardon, Ronald C Taylor, Nancy G Isern
BACKGROUND: Isotopic labeling is an analytic technique that is used to track the movement of isotopes through reaction networks. In general, the applicability of isotopic labeling techniques is limited to the investigation of reaction networks that consider homonuclear moieties, whose atoms are of one tracer element with two isotopes, distinguished by the presence of one additional neutron. RESULTS: This article presents a reformulation of the modeling framework for isotopic labeling, generalized to arbitrarily large, heteronuclear moieties, arbitrary numbers of isotopic tracer elements, and arbitrary numbers of isotopes per element, distinguished by arbitrary numbers of additional neutrons...
2017: Journal of Cheminformatics
https://www.readbyqxmd.com/read/28302981/studies-on-isotope-ratio-measurement-of-cl-by-inductively-coupled-plasma-triple-quad-mass-spectrometry
#19
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/28294174/docosahexaenoic-acid-enrichment-in-nafld-is-associated-with-improvements-in-hepatic-metabolism-and-hepatic-insulin-sensitivity-a-pilot-study
#20
L Hodson, L Bhatia, E Scorletti, D E Smith, N C Jackson, F Shojaee-Moradie, M Umpleby, P C Calder, C D Byrne
BACKGROUND/OBJECTIVE: Treatment of subjects with non-alcoholic fatty liver disease (NAFLD) with omega-3 polyunsaturated fatty acids (FAs) suggests high levels of docosahexaenoic acid (DHA) tissue enrichment decrease liver fat content. We assessed whether changes in erythrocyte DHA enrichment (as a surrogate marker of changes in tissue enrichment) were associated with alterations in hepatic de novo lipogenesis (DNL), postprandial FA partitioning and hepatic and peripheral insulin sensitivity in a sub-study of the WELCOME trial (Wessex Evaluation of fatty Liver and Cardiovascular markers in NAFLD (non-alcoholic fatty liver disease) with OMacor thErapy)...
March 15, 2017: European Journal of Clinical Nutrition
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