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https://www.readbyqxmd.com/read/28109742/development-of-a-new-uplc-esi-ms-ms-method-for-the-determination-of-biopterin-and-neopterin-in-dried-blood-spot
#1
Silvia Santagata, Emanuele Di Carlo, Carla Carducci, Vincenzo Leuzzi, Antonio Angeloni, Claudia Carducci
BACKGROUND: (6R)-5,6,7,8-tetrahydrobiopterin (BH4) deficiencies are rare inherited defects of synthesis or regeneration of BH4. Due to the resulting hyperphenylalaninemia (HPA), some of them are detectedby newborn screening and require the assessment of the pattern of neopterin (Neo) and biopterin (Bio) excretion in urine to be confirmed. Aim of presentstudy was to develop a method for the measurement of these diagnostic biomarkers in dried blood spot (DBS). METHODS: After DBS extraction, samples were filtered and injected into the UPLC column coupled with atandem mass spectrometer working in positive electrospray ionization...
January 18, 2017: Clinica Chimica Acta; International Journal of Clinical Chemistry
https://www.readbyqxmd.com/read/28109297/effects-of-phenolic-constituents-of-daylily-flowers-on-corticosterone-and-glutamate-treated-pc12-cells
#2
Huan Tian, Fei-Fei Yang, Chun-Yu Liu, Xin-Min Liu, Rui-Le Pan, Qi Chang, Ze-Sheng Zhang, Yong-Hong Liao
BACKGROUND: Daylily flowers, the flower and bud parts of Hemerocallis citrina or H. fulva, are well known as Wang-You-Cao in Chinese, meaning forget-one's sadness plant. However, the major types of active constituents responsible for the neurological effects remain unclear. This study was to examine the protective effects of hydroalcoholic extract and fractions and to identify the active fractions. METHODS: The extract of daylily flowers was separated with AB-8 resin into different fractions containing non-phenolic compounds, phenolic acid derivatives and flavonoids as determined using UPLC-DAD chromatograms...
January 21, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28109283/ethanol-extracted-cameroonian-propolis-exerts-estrogenic-effects-and-alleviates-hot-flushes-in-ovariectomized-wistar-rats
#3
Stéphane Zingue, Chantal Beatrice Magne Nde, Thomas Michel, Derek Tantoh Ndinteh, Jules Tchatchou, Moïse Adamou, Xavier Fernandez, Fernand-Nestor Tchuenguem Fohouo, Colin Clyne, Dieudonné Njamen
BACKGROUND: Since the biological properties of propolis depend to the plants that can be found in a specific region, propolis from unexplored regions attracts the attention of scientists. Ethanolic extract of Cameroonian propolis (EEP) is used to treat various ailments including gynecological problems and amenorrhea. Since there were no scientific data to support the above claims, the present study was therefore undertaken to assess estrogenic properties of Cameroonian propolis. METHODS: To achieve our goal, the ability of EEP to induce MCF-7 cells proliferation in E-screen assay as well as to activate estrogen receptors α (ERα) and β (ERβ) in cell-based reporter gene assays using human embryonic kidney cells (HEK293T) transfected with ERs was tested...
January 21, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28108082/analysis-of-drugs-of-abuse-in-human-plasma-using-microextraction-by-packed-sorbents-and-ultra-high-performance-liquid-chromatography
#4
P Fernández, M González, M Regenjo, A M Ares, A M Fernández, R A Lorenzo, A M Carro
A miniaturized and simple method based on digitally programmed microextraction by packed sorbent (eVol(®)-MEPS) coupled to ultra-performance liquid chromatography (UPLC) has been developed for quantitative determination of three synthetic cathinones and seven conventional drugs of abuse and metabolites. The influence of several extraction parameters, such as washing and elution solvents were tested. In addition important variables affecting MEPS performance, namely sample volume, sorbent drying time, washing solvent volume, elution volume, number of extraction cycles, sorbent phase and pH, were evaluated using an asymmetrical screening design...
January 16, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28107992/designing-of-ordered-two-dimensional-gold-nanoparticles-film-for-cocaine-detection-in-human-urine-using-surface-enhanced-raman-spectroscopy
#5
Juan Meng, Xianghu Tang, Binbin Zhou, Qiwen Xie, Liangbao Yang
A novel and rapid method to detect cocaine in human urine has been developed by using self-assembly ordered two dimensional (2D) gold nanoparticles (GNPs) film as surface-enhanced Raman spectroscopy (SERS) substrates. In order to obtain high sensitivity, uniformity, and reproducibility of SERS platform, quasi-spherical, uniform GNPs were firstly synthesis using seed growth method, in which the GNPs have been functionalized with CTAB to form orderly close-packed GNPs film as SERS substrate. Importantly, the high-performance GNPs on solid substrates can produce a high yield of sub-10-nm gaps which can generate gigantic signals enhancement for analytes adsorbed GNPs surface...
March 1, 2017: Talanta
https://www.readbyqxmd.com/read/28107780/myb12-and-myb22-play-essential-roles-in-proanthocyanidin-and-flavonol-synthesis-in-red-fleshed-apple-malus-sieversii-f-niedzwetzkyana
#6
Nan Wang, Haifeng Xu, Shenghui Jiang, Zongying Zhang, Ninglin Lu, Huarong Qiu, Changzhi Qu, Yicheng Wang, Shujing Wu, Xuesen Chen
Flavonoids are major polyphenol compounds in plant secondary metabolism. Compared with cultivated apples, wild red-fleshed apples (Malus sieversii f. niedzwetzkyana) are excellent resources because of their high flavonoid content. In this work, R6R6, R6R1 and R1R1 genotypes were identified in an F1 segregating population of M. sieversii f. niedzwetzkyana. Significant differences in flavonoid compositions and contents were detected among the three genotypes by UPLC-ESI-TOF/MS analysis. Furthermore, two putative flavonoid-related genes encoding R2R3-MYB transcription factors, designated MYB12 and MYB22, were cloned and characterized...
January 20, 2017: Plant Journal: for Cell and Molecular Biology
https://www.readbyqxmd.com/read/28106740/chemical-composition-and-antioxidant-properties-of-powders-obtained-from-different-plum-juice-formulations
#7
Anna Michalska, Aneta Wojdyło, Grzegorz P Łysiak, Adam Figiel
Among popular crops, plum (Prunus domestica L.) has received special attention due to its health-promoting properties. The seasonality of this fruit makes it impossible to consume it throughout the year, so new products in a powder form may offer an alternative to fresh consumption and may be used as high-quality natural food ingredients. A 100% plum (cultivar "Valor") juice was mixed with three different concentrations of maltodextrin or subjected to sugars removal by amberlite-XAD column, and dried using the freeze, spray, and vacuum (40, 60, and 80 °C) drying techniques...
January 17, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28102710/development-and-validation-of-a-uplc-ms-ms-method-for-simultaneous-determination-of-fotagliptin-and-its-two-major-metabolites-in-human-plasma-and-urine
#8
Zhenlei Wang, Ji Jiang, Pei Hu, Qian Zhao
AIM: Fotagliptin is a novel dipeptidyl peptidase IV inhibitor under clinical development for the treatment of Type II diabetes mellitus. The objective of this study was to develop and validate a specific and sensitive ultra-performance liquid chromatography (UPLC)-MS/MS method for simultaneous determination of fotagliptin and its two major metabolites in human plasma and urine. Methodology & results: After being pretreated using an automatized procedure, the plasma and urine samples were separated and detected using a UPLC-ESI-MS/MS method, which was validated following the international guidelines...
January 19, 2017: Bioanalysis
https://www.readbyqxmd.com/read/28098395/first-uhplc-ms-ms-method-coupled-with-automated-on-line-spe-for-quantification-both-of-tacrolimus-and-everolimus-in-peripheral-blood-mononuclear-cells-and-its-application-on-samples-from-co-treated-pediatric-patients
#9
Debora Pensi, Amedeo De Nicolò, Michele Pinon, Clarissa Pisciotta, Pier Luigi Calvo, Antonello Nonnato, Renato Romagnoli, Francesco Tandoi, Giovanni Di Perri, Antonio D'Avolio
Tacrolimus (TAC, FK-506) and everolimus (EVE, RAD001) are immunosuppressors used to treat pediatric patients undergoing liver transplantation. Their hematic TDM by liquid chromatography became standard practice. However, it does not always reflect concentrations at their active site. Our aim was to develop and validate a new method for the simultaneous TAC and EVE quantification into target cells: Peripheral-Blood-Mononuclear-Cells (PBMCs). PBMCs were collected using Cell-Preparation-Tubes; cells number and MCV were evaluated by an automatic cell counter...
January 18, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28097668/detection-and-pharmacokinetics-of-salmeterol-in-thoroughbred-horses-following-inhaled-administration
#10
S J Fenwick, P R Hincks, J P Scarth, M E Wieder, L L Hillyer, S W Paine
Salmeterol is a man-made beta-2-adrenergic receptor agonist used to relieve bronchospasm associated with inflammatory airway disease in horses. Whilst judicious use is appropriate in horses in training, they cannot race with clinically effective concentrations of medications under the British Horseracing Authority's Rules of Racing. Salmeterol must therefore be withdrawn prior to race day and pharmacokinetic (PK) studies used to establish formal detection time advice. Salmeterol xinafoate (Serevent Evohaler(®) ) was administered (0...
January 17, 2017: Journal of Veterinary Pharmacology and Therapeutics
https://www.readbyqxmd.com/read/28092839/effect-and-mechanism-of-sorbus-pohuashanensis-hante-hedl-flavonoids-protect-against-arsenic-trioxide-induced-cardiotoxicity
#11
Xiaojin Yu, Zhenyu Wang, Zunpeng Shu, Zhengqing Li, Yuan Ning, Keli Yun, Haina Bai, Ruihai Liu, Wenli Liu
The cardiotoxicity of arsenic trioxide (ATO) limits its clinical application in cancer treatment. Evidences suggest that sorbus has antioxidant activity and its consumption has been linked with improved cardioprotection. In this study, we investigated the cardio-protective effect and mechanisms of Sorbus pohuashanensis (Hante) Hedl. flavonoids (SPF) against ATO in BALB/c mice and H9c2 cells. Eleven major flavonoids were confirmed by ultra-performance liquid chromatography electrospray ionization quadrupole time of flight mass spectrometry (UPLC-ESI-Q-TOF-MS)...
January 13, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28089753/simultaneous-quantitation-of-sphingoid-bases-by-uplc-esi-ms-ms-with-identical-13-c-encoded-internal-standards
#12
M Mirzaian, P Wisse, M J Ferraz, A R A Marques, P Gaspar, S V Oussoren, K Kytidou, J D C Codée, G van der Marel, H S Overkleeft, J M Aerts
Free sphingoid bases (lysosphingolipids) of primary storage sphingolipids are increased in tissues and plasma of several sphingolipidoses. As shown earlier by us, sphingoid bases can be accurately quantified using UPLC-ESI-MS/MS, particularly in combination with identical (13)C-encoded internal standards. The feasibility of simultaneous quantitation of sphingoid bases in plasma specimens spiked with a mixture of such standards is here described. The sensitivity and linearity of detection is excellent for all examined sphingoid bases (sphingosine, sphinganine, hexosyl-sphingosine (glucosylsphingosine), hexosyl2-sphingosine (lactosylsphingosine), hexosyl3-sphingosine (globotriaosylsphingosine), phosphorylcholine-sphingosine) in the relevant concentration range and the measurements show very acceptable intra- and inter-assay variation (<10% average)...
January 12, 2017: Clinica Chimica Acta; International Journal of Clinical Chemistry
https://www.readbyqxmd.com/read/28088737/the-hemostatic-effect-study-of-cirsium-setosum-on-regulating-%C3%AE-1-ars-via-mediating-norepinephrine-synthesis-by-enzyme-catalysis
#13
Nianwei Chang, Yanmei Li, Mengge Zhou, Jie Gao, Yuanyuan Hou, Min Jiang, Gang Bai
BACKGROUND: Cirsium setosum (CS) is the aboveground part of Cephalanoplos segetum Kitam. Although it has been used as a hemostatic treatment for thousands of years and is still in use today, the mechanism of CS on regulating ARs is still not clear. PURPOSE: In this study, we aimed to clarify the mechanism of CS on regulating ARs. METHODS: We developed a simple method based on UPLC/Q-TOF MS combined adrenergic receptor dual-luciferase reporter assay systems for the rapid determination of active constituents in CS...
January 12, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28088663/development-and-validation-of-a-sensitive-and-fast-uplc-ms-ms-method-for-simultaneous-determination-of-seven-bioactive-compounds-in-rat-plasma-after-oral-administration-of-guizhi-gancao-decoction
#14
Bin Ji, Limeng Zhuo, Bin Yang, Yang Wang, Lin Li, Miao Yu, Yunli Zhao, Zhiguo Yu
Rapid, sensitive, selective and accurate UPLC-MS/MS method was developed and fully validated for simultaneous determination of cinnamaldehyde, cinnamic acid, 2-methoxy cinnamic acid, glycyrrhizic acid, glycyrrhetinic acid, liquiritigenin and isoliquiritin in rat plasma after oral administration of Guizhi-gancao decoction. Plasma samples were processed with a simple protein precipitation technique using acetonitrile, followed by chromatographic separation using a Thermo Hypersil GOLD C18 column. A 11.0min linear gradient elution was used at a flow rate of 0...
January 9, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28088110/highly-sensitive-detection-of-cysteine-over-glutathione-and-homo-cysteine-new-insight-into-the-michael-addition-of-mercapto-group-to-maleimide
#15
Zhaoyang Chen, Qian Sun, Yuhua Yao, Xiaoxiang Fan, Weibing Zhang, Junhong Qian
A fluorescence "off-on" probe CMP for thiols was designed with coumarin as the fluorophore and maleimide as the receptor. The fluorescence of the coumarin was quenched through photoinduced electron transfer (PET) from the fluorophore to maleimide group. The Michael addition of the mercapto group toward maleimide formed a thioether with relatively weak fluorescence. The intramolecular nucleophilic substitution of amino group in cysteine (Cys) to alkylthio produced a much stronger fluorescent amino adduct, which was supported by UPLC-MS and NMR titration...
January 7, 2017: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/28088026/current-ambient-concentrations-of-ozone-in-panama-modulate-the-leaf-chemistry-of-the-tropical-tree-ficus-insipida
#16
Gerald F Schneider, Alexander W Cheesman, Klaus Winter, Benjamin L Turner, Stephen Sitch, Thomas A Kursar
Tropospheric ozone (O3) is a major air pollutant and greenhouse gas, affecting carbon dynamics, ecological interactions, and agricultural productivity across continents and biomes. Elevated [O3] has been documented in tropical evergreen forests, the epicenters of terrestrial primary productivity and plant-consumer interactions. However, the effects of O3 on vegetation have not previously been studied in these forests. In this study, we quantified ambient O3 in a region shared by forests and urban/commercial zones in Panama and found levels two to three times greater than in remote tropical sites...
December 27, 2016: Chemosphere
https://www.readbyqxmd.com/read/28074362/the-determination-and-fate-of-disinfection-by-products-from-ozonation-chlorination-of-fulvic-acid
#17
Xin Zhong, Chongwei Cui, Shuili Yu
Ozonation of fulvic acid (FA) can result in diverse intermediate oxidation by-products, significantly affecting disinfection by-product (DBP) formation following chlorination. The objective of this study was to provide insight into ozone reaction intermediates and reveal the possible formation pathway of DBPs from ozonation of FA due to the formation of intermediate oxidation by-products. Aldehydes, aromatic acids, short-chain acids, chloroform, and dichloroacetic acid were detected at various ozone dosage additions...
January 10, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28073545/a-validated-uplc-ms-ms-method-for-the-surveillance-of-ten-aquatic-biotoxins-in-european-brackish-and-freshwater-systems
#18
Brett Greer, Sara E McNamee, Bas Boots, Lucia Cimarelli, Delphine Guillebault, Karim Helmi, Stefania Marcheggiani, Stefan Panaiotov, Ulrich Breitenbach, Reyhan Akçaalan, Linda K Medlin, Katrin Kittler, Christopher T Elliott, Katrina Campbell
Over the past few decades, there has been an increased frequency and duration of cyanobacterial Harmful Algal Blooms (HABs) in freshwater systems globally. These can produce secondary metabolites called cyanotoxins, many of which are hepatotoxins, raising concerns about repeated exposure through ingestion of contaminated drinking water or food or through recreational activities such as bathing/swimming. An ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) multi-toxin method has been developed and validated for freshwater cyanotoxins; microcystins-LR, -YR, -RR, -LA, -LY and -LF, nodularin, cylindrospermopsin, anatoxin-a and the marine diatom toxin domoic acid...
May 2016: Harmful Algae
https://www.readbyqxmd.com/read/28069691/rapid-and-sensitive-determination-of-major-active-ingredients-and-toxic-components-in-ginkgobiloba-leaves-extract-egb-761-by-a-validated-uplc-ms-ms-method
#19
Yao Wang, Yuan Liu, Qi Wu, Xin Yao, Zongqi Cheng
An accurate, precise and sensitive ultra-performance liquid chromatography tandem mass spectrometric (UPLC-MS-MS) method was developed for the determination of flavonoids, terpene lactones, together with ginkgolic acids in Ginkgo biloba leaves extract (EGb 761). This is the first report of the simultaneous analysis of major active ingredients and toxic components in EGb 761 using UPLC-MS-MS. This analysis afforded good linearity, precision, repeatability and accuracy. In addition, the content of those major bioactive components in EGb 761 prepared by different manufacturers of China was determined to establish the effectiveness of the method...
January 8, 2017: Journal of Chromatographic Science
https://www.readbyqxmd.com/read/28069121/investigating-the-inhibitory-activity-and-mechanism-differences-between-norartocarpetin-and-luteolin-for-tyrosinase-a-combinatory-kinetic-study-and-computational-simulation-analysis
#20
Long Zhang, Xin Zhao, Guan-Jun Tao, Jie Chen, Zong-Ping Zheng
Flavonoids are an important type of natural tyrosinase inhibitor, but their inhibitory activity and mechanism against tyrosinase are very different because of their different structures. In this study, the inhibitory activity and mechanism differences between norartocarpetin and luteolin for tyrosinase were investigated by a combination of kinetic studies and computational simulations. The kinetic analysis showed that norartocarpetin reversibly inhibited tyrosinase in a competitive manner, whereas luteolin caused reversible noncompetitive inhibition...
May 15, 2017: Food Chemistry
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