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https://www.readbyqxmd.com/read/28214376/sensitive-quantification-of-coixol-a-potent-insulin-secretagogue-in-scoparia-dulcis-extract-using-high-performance-liquid-chromatography-combined-with-tandem-mass-spectrometry-and-uv-detection
#1
Arslan Ali, Faraz Ul Haq, Qamar Ul Arfeen, Khaga Raj Sharma, Achyut Adhikari, Syed Ghulam Musharraf
Diabetes is a major global health problem which requires new studies for its prevention and control. Scoparia dulcis, an herbal product, is widely used for treatment of diabetes. Recent studies demonstrate coixol as a potent and non-toxic insulin secretagogue from S. dulcis. This study focuses on developing two quantitative methods of coixol in Scoparia dulcis methanol-based extracts. Quantification of coixol was performed using high performance liquid chromatography-tandem mass spectrometry (method 1) and high performance liquid chromatography-ultraviolet detection (method 2) with limit of detection of 0...
February 18, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28214354/long-chain-unsaturated-fatty-acids-as-possible-important-metabolites-for-primary-angle-closure-glaucoma-based-on-targeted-metabolomic-analysis
#2
Shengzhong Rong, Yang Li, Yue Guan, Lili Zhu, Qiang Zhou, Mucong Gao, Hongzhi Pan, Lina Zou, Dong Chang
Primary angle-closure glaucoma (PACG) is a severe chronic neurodegenerative disease in Asia. Identification of important metabolites associated with PACG is crucial for early intervention and advancing knowledge of the disease mechanism. We applied gas chromatography-mass spectrometry (GC-MS) for targeted metabolomic analysis on serum samples from thirty-eight newly diagnosed PACG patients and forty-eight controls. Palmitoleic acid (PA), linoleic acid (LA), gamma-linolenic acid (GLA) and arachidonic acid (ARA) were identified as important metabolites associated with PACG...
February 18, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28214288/an-accelerator-mass-spectrometry-enabled-microtracer-study-to-evaluate-the-first-pass-effect-on-the-absorption-of-yh4808
#3
Anhye Kim, Byung-Yong Yu, Stephen R Dueker, Kwang-Hee Shin, Hwa Suk Kim, Hyungmi Ahn, Joo-Youn Cho, Kyung-Sang Yu, In-Jin Jang, Howard Lee
(14) C-labeled YH4808, a novel potassium-competitive acid blocker, was intravenously administered as a microtracer at 80 μg (11.8 kBq or 320 nCi) concomitantly with the non-radiolabeled oral drug at 200 mg to determine the absolute bioavailability and to assess the effect of pharmacogenomics on the oral absorption of YH4808. The absolute bioavailability was low and highly variable (mean, 10.1%; range, 2.3-19.3%), and M3 and M8, active metabolites of YH4808, were formed 22.6- and 38.5-fold higher after oral administration than intravenous administration, respectively...
February 18, 2017: Clinical Pharmacology and Therapeutics
https://www.readbyqxmd.com/read/28214264/identification-of-candidate-cerebrospinal-fluid-biomarkers-in-parkinsonism-using-quantitative-proteomics
#4
N K Magdalinou, A J Noyce, R Pinto, E Lindstrom, J Holmén-Larsson, M Holtta, K Blennow, H R Morris, T Skillbäck, T T Warner, A J Lees, I Pike, M Ward, H Zetterberg, J Gobom
INTRODUCTION: Neurodegenerative parkinsonian syndromes have significant clinical and pathological overlap, making early diagnosis difficult. Cerebrospinal fluid (CSF) biomarkers may aid the differentiation of these disorders, but other than α-synuclein and neurofilament light chain protein, which have limited diagnostic power, specific protein biomarkers remain elusive. OBJECTIVES: To study disease mechanisms and identify possible CSF diagnostic biomarkers through discovery proteomics, which discriminate parkinsonian syndromes from healthy controls...
January 31, 2017: Parkinsonism & related Disorders
https://www.readbyqxmd.com/read/28214238/high-prevalence-of-low-serum-biologically-active-testosterone-in%C3%A2-older-male-veterans
#5
Christine F Conover, Joshua F Yarrow, Timothy J Garrett, Fan Ye, Eoin P Quinlivan, Darryl F Cannady, Mark D Peterson, Stephen E Borst
OBJECTIVES: Assess the prevalence of hypogonadism in older male Veterans by comparing direct measurements of total testosterone (T) and bioavailable testosterone (BioT) versus indirect BioT values derived from existing and newly developed regression analyses. DESIGN: Cohort study. SETTING: Malcom Randall VA Medical Center, Gainesville, FL. PARTICIPANTS: Community-dwelling male Veterans aged 60 and older (n = 203). MEASUREMENTS: Total T, BioT, albumin, sex hormone-binding globulin (SHBG), and body mass index were evaluated...
February 14, 2017: Journal of the American Medical Directors Association
https://www.readbyqxmd.com/read/28213886/dysregulation-of-metabolic-pathways-in-a-mouse-model-of-allergic-asthma
#6
Kevin D Quinn, Michaela Schedel, Yasmeen Nkrumah-Elie, Anthony Joetham, Michael Armstrong, Charmion Cruickshank-Quinn, Richard Reisdorph, Erwin W Gelfand, Nichole Reisdorph
BACKGROUND: Asthma is a complex lung disease resulting from the interplay of genetic and environmental factors. To understand the molecular changes that occur during the development of allergic asthma without genetic and environmental confounders, an experimental model of allergic asthma in mice was used. Our goals were to (1) identify changes at the small molecule level due to allergen exposure, (2) determine perturbed pathways due to disease, and (3) determine whether small molecule changes correlate with lung function...
February 18, 2017: Allergy
https://www.readbyqxmd.com/read/28213728/fourier-transform-ion-cyclotron-resonance-mass-spectrometry-at-the-cyclotron-frequency
#7
Konstantin O Nagornov, Anton N Kozhinov, Yury O Tsybin
The phenomenon of ion cyclotron resonance allows for determining mass-to-charge ratio, m/z, of an ensemble of ions by means of measurements of their cyclotron frequency, ω c . In Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), the ω c quantity is usually unavailable for direct measurements: the resonant state is located close to the reduced cyclotron frequency (ω+), whereas the ω c and the corresponding m/z values may be calculated via theoretical derivation from an experimental estimate of the ω+ quantity...
February 17, 2017: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/28213708/removal-mechanisms-for-extremely-high-level-fluoroquinolone-antibiotics-in-pharmaceutical-wastewater-treatment-plants
#8
Xinyan Guo, Zheng Yan, Yi Zhang, Xiangji Kong, Deyang Kong, Zhengjun Shan, Na Wang
Pharmaceutical wastewater treatment plants (PWWTPs) receive industrial effluents from the plant that contain extremely high levels of antibiotics and are regarded as one of the major sources of antibiotics in the environment. Two PWWTPs have been selected in Zhejiang Province, China, to assess the removal mechanisms of fluoroquinolone antibiotics (FQs). PWWTP A uses activated sludge with biocarriers in a moving bed biofilm reactor in anoxic and aerobic units, and PWWTP B uses biological units under anaerobic, aerobic, and anoxic conditions...
February 17, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28213610/prebiotic-inulin-type-fructans-induce-specific-changes-in-the-human-gut-microbiota
#9
Doris Vandeputte, Gwen Falony, Sara Vieira-Silva, Jun Wang, Manuela Sailer, Stephan Theis, Kristin Verbeke, Jeroen Raes
OBJECTIVE: Contrary to the long-standing prerequisite of inducing selective (ie, bifidogenic) effects, recent findings suggest that prebiotic interventions lead to ecosystem-wide microbiota shifts. Yet, a comprehensive characterisation of this process is still lacking. Here, we apply 16S rDNA microbiota profiling and matching (gas chromatography mass spectrometry) metabolomics to assess the consequences of inulin fermentation both on the composition of the colon bacterial ecosystem and faecal metabolites profiles...
February 17, 2017: Gut
https://www.readbyqxmd.com/read/28213406/mitochondria-regulated-formation-of-endothelial-extracellular-vesicles-shifts-the-mediator-of-flow-induced-vasodilation
#10
Julie K Freed, Matthew J Durand, Brian Robert Hoffmann, John C Densmore, Andrew S Greene, David D Gutterman
In order to examine the effect of endothelial-derived extracellular vesicles (eEVs) on the mechanism of flow-induced dilation (FID) composition, formation, and functional effects on the mechanism of FID were examined from two different eEV subtypes, one produced from ceramide, the other from plasminogen-activator inhibitor 1 (PAI-1). Using videomicroscopy, internal diameter changes in response to increases in flow were measured in human adipose resistance arteries acutely exposed (30min) to eEVs derived from cultured endothelial cells exposed to ceramide or PAI-1...
February 17, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/28213336/linking-the-mobilization-of-dissolved-organic-matter-in-catchments-and-its-removal-in-drinking-water-treatment-to-its-molecular-characteristics
#11
Julia Raeke, Oliver J Lechtenfeld, Jörg Tittel, Marieke R Oosterwoud, Katrin Bornmann, Thorsten Reemtsma
Drinking water reservoirs in the Northern Hemisphere are largely affected by the decadal-long increase in riverine dissolved organic carbon (DOC) concentrations. The removal of DOC in drinking water treatment is costly and predictions are needed to link DOC removal efficiency to its mobilization in catchments, both of which are determined by the molecular composition. To study the effect of hydrological events and land use on the molecular characteristics of dissolved organic matter (DOM), 36 samples from three different catchment areas in the German low mountain ranges, with DOC concentrations ranging from 3 to 32 mg L(-1), were examined...
February 8, 2017: Water Research
https://www.readbyqxmd.com/read/28213295/determination-of-imm-h004-a-novel-neuroprotective-agent-in-rat-plasma-and-brain-tissue-by-liquid-chromatography-tandem-mass-spectrometry
#12
Ziqian Zhang, Xiangmeng Wu, Manman Zhao, Yakun Yang, Yan Wang, Jinping Hu, Baolian Wang, Li Sheng, Yan Li
A rapid and sensitive liquid chromatography-tandem mass spectrometry method for determination of IMM-H004, a novel neuroprotective agent, in rat plasma and brain was developed. Plasma and brain tissue homogenate samples containing IMM-H004 and propranolol (internal standard, IS) were prepared by using a direct protein precipitation of acetonitrile. Separation was carried out in Zorbax SB-C18 column at a flow rate of 0.3mL/min utilizing acetonitrile/water as mobile phases which contain 0.5% formic acid (v/v)...
February 6, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28213261/a-method-for-the-analysis-of-sugars-in-biological-systems-using-reductive-amination-in-combination-with-hydrophilic-interaction-chromatography-and-high-resolution-mass-spectrometry
#13
Sami Bawazeer, Ali Muhsen Ali, Aliyah Alhawiti, Abedawn Khalaf, Colin Gibson, Jonans Tusiimire, David G Watson
Separation of sugar isomers extracted from biological samples is challenging because of their natural occurrence as alpha and beta anomers and, in the case of hexoses, in their pyranose and furanose forms. A reductive amination method was developed for the tagging of sugars with the aim of it becoming part of a metabolomics work flow. The best separation of the common hexoses (glucose, fructose, mannose and galactose) was achieved when (2)H5-aniline was used as the tagging reagent in combination with separation on a ZICHILIC column...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28213245/one-pot-synthesis-of-gold-carbon-dots-nanocomposite-and-its-application-for-cytosensing-of-metals-for-cancer-cells
#14
Hani Nasser Abdelhamid, Abuo Talib, Hui-Fen Wu
Cytosensing of biological transition metals is paramount important for cancer research. One-pot synthesis of the nanocomposite of carbon dots (CDs) and gold nanoparticles (AuNPs) is reported and has been applied for metal cytosensing. The nanocomposite (GCDs) is synthesized using citric acid (CA) and L-cysteine as precursors in the presence of chloroauric acid. The synthesis procedure exhibits many advantages including simple one step, green approach (solvent free method) and requires cheap chemical precursors...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28213243/multi-residue-analysis-of-36-priority-and-emerging-pollutants-in-marine-echinoderms-holothuria-tubulosa-and-marine-sediments-by-solid-liquid-extraction-followed-by-dispersive-solid-phase-extraction-and-liquid-chromatography-tandem-mass-spectrometry-analysis
#15
J Martín, A Zafra-Gómez, F Hidalgo, A J Ibáñez-Yuste, E Alonso, J L Vilchez
Marine echinoderms are filter-feeding invertebrates widely distributed along the coasts, and which are therefore extensively exposed to anthropogenic xenobiotics. They can serve as good sentinels for monitoring a large variety of contaminants in marine ecosystems. In this context, a multi-residue analytical method has been validated and applied to Holothuria tubulosa specimens and marine sediments for the determination of 36 organic compounds, which belong to some of the most problematic groups of emerging and priority pollutants (perfluoroalkyl compounds, estrogens, parabens, benzophenones, plasticizers, surfactants, brominated flame retardants and alkylphenols)...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28213240/sensitive-and-precise-monitoring-of-phosphatidylethanol-in-human-blood-as-a-biomarker-for-alcohol-intake-by-ultrasound-assisted-dispersive-liquid-liquid-microextraction-combined-with-liquid-chromatography-tandem-mass-spectrometry
#16
Siming Wang, Ruiyue Yang, Fusui Ji, Hongxia Li, Jun Dong, Wenxiang Chen
Phosphatidylethanol (PEth) is a special phospholipid that is only formed in the presence of ethanol, and therefore, serves as a promising biomarker for alcohol intake. In this study, a simple, rapid and precise method based on LC-MS/MS combined with ultrasound-assisted dispersive liquid-liquid microextraction was developed and validated for the measurements of PEth (16:0/18:1, 16:0/18:2, 16:0/16:0, and 18:1/18:1) in human blood. The influences of several variables for sample extraction and MS detection were carefully investigated...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28213239/new-urea-modified-paper-substrate-for-enhanced-analytical-performance-of-negative-ion-mode-paper-spray-mass-spectrometry
#17
Jingjing Liu, Yan He, Shuo Chen, Ming Ma, Shouzuo Yao, Bo Chen
Electrospray ionization mass spectrometry (ESI-MS) analysis in the negative ion mode is adversely affected by ionization suppression caused by electrical discharge and the presence of salts. Paper spray mass spectrometry (PS-MS) also suffers from the above phenomenon, being built on principles similar to those of ESI. Herein, we report the use of a paper substrate modified by 1-[3-(trimethoxysilyl)propyl]urea to improve the sensitivity of quantitative PS-MS analysis in the negative ion mode. The obtained results demonstrated that the urea modified paper substrate can effectively bind anions and highly polar compounds in the sample solution, decreasing competitive ionization in the negative ion mode of PS-MS and significantly reducing the signal intensity of Cl(-) adducts...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28213231/stable-isotope-labeling-assisted-liquid-chromatography-tandem-mass-spectrometry-for-the-analysis-of-perfluorinated-carboxylic-acids-in-serum-samples
#18
Shijuan Zhang, Zhongyin Ji, Zhiwei Sun, Mingshuang Li, Cuncun Sheng, Mingbo Yue, Yanxin Yu, Guang Chen, Jinmao You
A new stable isotope labeling (SIL) reagent pair, 10-methyl-acridone-2-sulfonohydrazide (MASH) and its deuterated counterpart d3-MASH was synthesized and successfully applied to the analysis of perfluorinated carboxylic acids (PFCAs) in serum samples. The limits of detection (LODs) were in the range of 0.07-0.42μg/L, and the limits of quantitation (LOQs) were in the range of 0.25-1.38μg/L. Besides ionization enhancing effect, MASH also showed excellent fluorescence property. Therefore, the mass spectrometer operation cost was greatly lowered by carrying out parameter optimization experiments on HPLC which is easier to operate and maintain...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28213229/fast-method-to-quantify-pahs-in-contaminated-soils-by-direct-thermodesorption-using-analytical-pyrolysis
#19
C Biache, C Lorgeoux, A Saada, S Colombano, P Faure
A method for polycyclic aromatic hydrocarbon (PAH) quantification, based on pyrolysis at 450°C combined with gas chromatography coupled with mass spectrometry and flame ionization detection (Py-GC-MS/FID), was developed and compared to a conventional PAH quantification method using accelerated solvent extraction and GC-MS analyses. The PAH contents of three coking plant soils, one gas plant soil, two wood-treating facility soils and one certified reference material (CRM - BCR 524) were determined using both methods...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28213213/titanium-iv-ion-modified-covalent-organic-frameworks-for-specific-enrichment-of-phosphopeptides
#20
Heping Wang, Fenglong Jiao, Fangyuan Gao, Yayao Lv, Qiong Wu, Yan Zhao, Yehua Shen, Yangjun Zhang, Xiaohong Qian
To date, plenty of new alternative materials for phosphopeptides enrichment prior to mass spectrometry (MS) analysis appear, especially immobilized metal ion affinity chromatography (IMAC) materials. The variable combinations with different metal ions, chelating ligands and solid supports offer full of optionality for IMAC. However, further improvement was predicted by the tedious and complex synthetic process. In this work, a novel covalent organic framework (COF)-based IMAC material (denoted TpPa-2-Ti(4+)) was prepared simply by direct immobilizing Ti (IV) into TpPa-2 COFs without any extra chelating ligands...
May 1, 2017: Talanta
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