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https://www.readbyqxmd.com/read/28215026/separation-of-peptides-on-superficially-porous-particle-based-macrocyclic-glycopeptide-liquid-chromatography-stationary-phases-consideration-of-fast-separations
#1
Rasangi M Wimalasinghe, Zachary S Breitbach, Jauh T Lee, Daniel W Armstrong
Macrocyclic glycopeptide based liquid chromatography stationary phases are known for their highly selective peptide separations. Fast and ultrafast (t R < 1 min) high-efficiency separations were achieved with superficially porous particle (SPP)-based stationary phases. Separations of pharmaceutically important classes of peptides such as enkephalins and bradykinins have been achieved in less than 5 min in isocratic elution modes. Selectivity for peptides structurally similar to one another was increased with use of teicoplanin-based stationary phases compared with commercial C18 stationary phases...
February 18, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28214939/selective-determination-of-sulfonamides-from-environmental-water-based-on-magnetic-surface-molecularly-imprinting-technology
#2
Yang Xu, Qi Zhao, Liyan Jiang, Zhengqiang Li, Yanhua Chen, Lan Ding
In the study, a simple and selective method based on magnetic separation technology is presented for the extraction of sulfonamides (SAs) from environmental water, followed by liquid chromatography-tandem mass spectrometry. In this method, magnetic surface molecularly imprinted polymers (Fe3O4@SiO2@MIPs) with super-paramagnetic property and high selectivity toward SAs were developed as magnetic adsorbents. The Fe3O4@SiO2@MIPs were then applied to the selective extraction of SAs from environmental water. The extraction and enrichment were accomplished simultaneously in a single step by simply stirring the mixture of adsorbents and water samples...
February 18, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28214830/hyper-elongation-in-colorectal-cancer-tissue-cerotic-acid-is-a-potential-novel-serum-metabolic-marker-of-colorectal-malignancies
#3
Adriana Mika, Jaroslaw Kobiela, Aleksandra Czumaj, Michał Chmielewski, Piotr Stepnowski, Tomasz Sledzinski
BACKGROUNDS/AIMS: Colorectal cancer (CRC) cells show some alterations of lipid metabolism. Elongation of fatty acids (FA) has not been studied in CRC tissues thus far. The aim of this study was to verify if CRC specimens and normal colon mucosa differ in terms of their levels of very long-chain FAs, a product of FA elongation. Moreover, the expression of elongase genes has been studied in normal tissue and CRC. Finally, we searched for some specific products of FA elongation in serum of CRC patients...
February 8, 2017: Cellular Physiology and Biochemistry
https://www.readbyqxmd.com/read/28214755/identification-of-a-new-tert-leucinate-class-synthetic-cannabinoid-in-powder-and-spice-like-herbal-incenses-methyl-2-1-5-fluoropentyl-indole-3-carbonyl-amino-3-3-dimethyl-butanoate-5f-mdmb-pica
#4
Martijn D P Risseeuw, Peter Blanckaert, Vera Coopman, Stijn Van Quekelberghe, Serge Van Calenbergh, Jan Cordonnier
A brown powder and different product packages of "spice-like" herbal incenses were analyzed using a systematic identification approach based on liquid chromatography with diode array detector (HPLC-PDA) and gas chromatography mass spectrometry (GC-MS) with computer based library search against spectral libraries. However, the most predominant compound in the methanolic sample solutions could not be identified. In order to elucidate the chemical structure, a more extensive analysis of the material was initiated using liquid chromatography mass spectrometry (LC-MS), electrospray high resolution mass spectrometry (ESI-HRMS) and (1)H, (13)C and (19)F nuclear magnetic resonance spectroscopy (NMR), which allowed the identification and characterization of the major compound as methyl 2-[[1-(5-fluoropentyl)indole-3-carbonyl]amino]-3,3-dimethyl-butanoate (5F-MDMB-PICA)...
February 4, 2017: Forensic Science International
https://www.readbyqxmd.com/read/28214687/gastroprotective-effect-and-mechanism-of-action-of-croton-rhamnifolioides-essential-oil-in-mice
#5
Cinara Soares Vidal, Anita Oliveira Brito Pereira Bezerra Martins, Andressa de Alencar Silva, Maria Rayane Correia de Oliveira, Jaime Ribeiro-Filho, Thaís Rodrigues de Albuquerque, Henrique Douglas Melo Coutinho, Jackson Roberto Guedes da Silva Almeida, Lucindo Jose Quintans, Irwin Rose Alencar de Menezes
BACKGROUND: Croton rhamnifolioides Pax is a plant species that have been used in the folk medicine to treat ulcers, inflammations and hypertension. However, despite the relevant data obtained from ethnopharmacological studies, the pharmacological properties endorsing the efficacy of this plant to treat ulcer remain to be elucidated. HYPOTHESIS/PURPOSE: The present study aimed to characterize the chemical profile and evaluate the gastroprotective activity of the essential oil obtained from C...
February 16, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
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
#6
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
#7
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
#8
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
#9
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
#10
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
#11
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
#12
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
#13
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
#14
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
#15
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
#16
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
#17
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
#18
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
#19
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
#20
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
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