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https://www.readbyqxmd.com/read/28211337/enhanced-electrochemical-degradation-of-ibuprofen-in-aqueous-solution-by-ptru-alloy-catalyst
#1
Chiung-Fen Chang, Tsan-Yao Chen, Ching-Ju Monica Chin, Yu-Tsun Kuo
Electrochemical advanced oxidation processes (EAOPs) regarded as a green technology for aqueous ibuprofen treatment was investigated in this study. Multi-walled carbon nanotubes (MWCNTs), Pt nanoparticles (Pt NPs), and PtRu alloy, of which physicochemical properties were characterized by XRD and X-ray absorption spectroscopy, were used to synthesize three types of cheap and effective anodes based on commercial conductive glass. Furthermore, the operating parameters, such as the current densities, initial concentrations, and solution pH were also investigated...
February 6, 2017: Chemosphere
https://www.readbyqxmd.com/read/28208751/oxidative-stress-related-genetic-variants-may-modify-associations-of-phthalate-exposures-with-asthma
#2
I-Jen Wang, Wilfried J J Karmaus
Background: Phthalate exposure may increase the risk of asthma. Little is known about whether oxidative-stress related genes may alter this association. First, this motivated us to investigate whether genetic polymorphisms of the oxidative-stress related genes glutathione S-transferase Mu 1 (GSTM1), glutathione S-transferase pi 1 (GSTP1), superoxide dismutase 2 (SOD2), catalase (CAT), myeloperoxidase (MPO), and EPHX1 in children are associated with phthalate urine concentrations. Second, we addressed the question whether these genes may affect the influence of phthalates on asthma...
February 8, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28205294/simultaneous-determination-of-the-bioactive-components-in-rat-plasma-by-uplc-ms-ms-and-application-in-pharmacokinetic-studies-after-oral-administration-of-radix-scutellariae-extract
#3
Jin-Hua Tao, Jun Xu, Shu Jiang, Yong Ling, Dong-Geng Wang
A highly sensitive and rapid ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) has been developed and validated for simultaneous quantification of the four main bioactive compounds, i.e., baicalin, baicalein, wogonoside and wogonin in rat plasma after oral administration of Radix scutellariae extract. Clarithromycin was used as an internal standard (IS). Plasma samples were processed by protein precipitation with methanol. The separation was performed on an Acquity BEH C18 column (100 mm × 2...
February 16, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28204488/correction-to-simultaneous-screening-and-quantification-of-basic-neutral-and-acidic-drugs-in-blood-using-uplc-qtof-ms
#4
Sergei Bidny, Kim Gago, Phuong Chung, Desdemona Albertyn, Daniel Pasin
No abstract text is available yet for this article.
February 16, 2017: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/28203771/a-rapid-uplc-method-for-simultaneous-analysis-of-caffeine-and-13-index-polyphenols-in-black-tea
#5
Hai-Bo Pan, Dan Zhang, Bo Li, Yuan-Yuan Wu, You-Ying Tu
No abstract text is available yet for this article.
February 14, 2017: Journal of Chromatographic Science
https://www.readbyqxmd.com/read/28203476/development-of-a-novel-sensitive-selective-and-fast-methodology-to-determine-malondialdehyde-in-leaves-of-melon-plants-by-ultra-high-performance-liquid-chromatography-tandem-mass-spectrometry
#6
Melisa E Yonny, Ariel Rodríguez Torressi, Mónica A Nazareno, Soledad Cerutti
Early production of melon plant (Cucumis melo) is carried out using tunnels structures, where extreme temperatures lead to high reactive oxygen species production and, hence, oxidative stress. Malondialdehyde (MDA) is a recognized biomarker of the advanced oxidative status in a biological system. Thus a reliable, sensitive, simple, selective, and rapid separative strategy based on ultra-high-performance liquid chromatography coupled to positive electrospray-tandem mass spectrometry (UPLC-(+)ESI-MS/MS) was developed for the first time to measure MDA, without derivatization, in leaves of melon plants exposed to stress conditions...
2017: Journal of Analytical Methods in Chemistry
https://www.readbyqxmd.com/read/28199916/isolation-of-four-phenolic-compounds-from-mangifera-indica-l-flowers-by-using-normal-phase-combined-with-elution-extrusion-two-step-high-speed-countercurrent-chromatography
#7
Nusrat Shaheen, Yanzhen Lu, Ping Geng, Qian Shao, Yun Wei
Two-step high speed countercurrent chromatography method, following normal phase and elution-extrusion mode of operation by using selected solvent systems, was introduced for phenolic compounds separation. Phenolic compounds including gallic acid, ethyl gallate, ethyl digallate and ellagic acid were separated from the ethanol extract of mango (Mangifera indica L.) flowers for the first time. In the first step, gallic acid of 3.7mg and ethyl gallate of 3.9mg with the purities of 98.87% and 99.55%, respectively, were isolated by using hexane-ethylacetate-methanol-water (4:6:4:6, v/v) in normal phase high speed countercurrent chromatography from 200mg of crude extract, while ethyl digallate and ellagic acid were collected in the form of mixture fraction...
January 15, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28197798/inhibition-of-proinflammatory-pathways-by-bioactive-fraction-of-tinospora-cordifolia
#8
Jenny Jacob, Bashi M Babu, Mohind C Mohan, A P Abhimannue, B Prakash Kumar
Tinospora cordifolia (Willd.) Miers ex Hook. f. & Thomson, a known immunomodulatory agent extensively used in ayurveda, has not been effectively validated for the mechanisms involved in immunomodulation and the identification of the active principles. The bioactive fraction of T. cordifolia (TBF) in methanol was used for nitric oxide (NO) radical scavenging activity, lipoxygenase (LOX) and cyclooxygenase (COX) dual inhibition and cytotoxicity studies. Production of the proinflammatory cytokines, tumour necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in dendritic cell (DC) suspensions treated with lipopolysaccharide (LPS) was also studied...
February 15, 2017: Inflammopharmacology
https://www.readbyqxmd.com/read/28197590/rats-urinary-metabolomes-reveal-the-potential-roles-of-functional-foods-and-exercise-in-obesity-management
#9
Mohamed A Farag, N M Ammar, T E Kholeif, N S Metwally, N M El-Sheikh, Ludger A Wessjohann, A Z Abdel-Hamid
The complexity of the metabolic changes in obese individuals still presents a challenge for the understanding of obesity-related metabolic disruptions and for obesity management. In this study, a gas chromatography mass spectrometry (GC-MS) based metabolomics approach targeting urine metabolism has been applied to assess the potential roles of functional foods and exercise for obesity management in rats. Male albino rats diagnosed as obese via histopathology and biochemical assays were administered functional foods in common use for obesity management including pomegranate, grapefruit, and red cabbage juice extracts in parallel with swimming exercise...
February 15, 2017: Food & Function
https://www.readbyqxmd.com/read/28195465/identification-and-relative-quantification-of-bioactive-peptides-sequentially-released-during-simulated-gastrointestinal-digestion-of-commercial-kefir
#10
Yufang Liu, Monika Pischetsrieder
Health-promoting effects of kefir may be partially caused by bioactive peptides. To evaluate their formation or degradation during gastrointestinal digestion, we monitored changes of the peptide profile in a model of oral (1), gastric (2) and small intestinal (3) digestion of kefir. MALDI-TOF-MS analyses revealed clearly different profiles between digests 2/3 and kefir/digest 1. Subsequent UPLC-ESI-MS/MS identified 92 peptides in total (25, 25, 43, and 30, partly overlapping in kefir and digests 1, 2, and 3, respectively), including 16 peptides with ascribed bioactivity...
February 14, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28194962/high-speed-quantitative-uplc-ms-analysis-of-multiple-amines-in-human-plasma-and-serum-via-precolumn-derivatization-with-6-aminoquinolyl-n-hydroxysuccinimidyl-carbamate-application-to-acetaminophen-induced-liver-failure
#11
Nicola Gray, Rabiya Zia, Adam King, Vishal C Patel, Julia Wendon, Mark J W McPhail, Muireann Coen, Robert S Plumb, Ian D Wilson, Jeremy K Nicholson
A targeted reversed-phase gradient UPLC-MS/MS assay has been developed for the quantification /monitoring of 66 amino acids and amino-containing compounds in human plasma and serum using precolumn derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AccQTag Ultra). Derivatization of the target amines required minimal sample preparation and resulted in analytes with excellent chromatographic and mass spectrometric detection properties. The resulting method, which requires only 10 μL of sample, provides the reproducible and robust separation of 66 analytes in 7...
February 7, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28194233/checkpoints-for-preliminary-identification-of-small-molecules-found-enriched-in-autophagosomes-and-activated-mast-cell-secretions-analyzed-by-comparative-uplc-ms-e
#12
Chad P Satori, Marzieh Ramezani, Joseph S Koopmeiners, Audrey F Meyer, Jose A Rodriguez-Navarro, Michelle M Kuhns, Thane H Taylor, Christy L Haynes, Joseph J Dalluge, Edgar A Arriaga
We report the use of ultra high performance liquid chromatography (UPLC) coupled with acquisition of low- and high-collision energy mass spectra (MS(e)) to explore small molecule compositions that are unique to either enriched-autophagosomes or secretions of chemically activated murine mast cells. Starting with thousands of features, each defined by a chromatographic retention time, m/z values and ion intensities, manual examination of the extracted ion chromatograms (XIC) of chemometrically selected features was essential to eliminate false positives, occurring at rates of 33, 14 and 37% in samples of three biological systems...
2017: Analytical Methods: Advancing Methods and Applications
https://www.readbyqxmd.com/read/28193401/multiresponse-optimization-of-a-uplc-method-for-the-simultaneous-determination-of-tryptophan-and-15-tryptophan-derived-compounds-using-a-box-behnken-design-with-a-desirability-function
#13
Widiastuti Setyaningsih, Irfan E Saputro, Ceferino A Carrera, Miguel Palma, Carmelo G Barroso
A Box-Behnken design was used in conjunction with multiresponse optimization based on the desirability function to carry out the simultaneous separation of tryptophan and 15 derivatives by Ultra Performance Liquid Chromatography. The gradient composition of the mobile phase and the flow rate were optimized with respect to the resolution of severely overlapping chromatographic peaks and the total run time. Two different stationary phases were evaluated (hybrid silica and a solid-core-based C18 column). The methods were validated and a suitable sensitivity was found for all compounds in the concentration range 1-100μgL(-1) (R(2)>0...
June 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28193047/accurate-direct-and-high-throughput-analyses-of-a-broad-spectrum-of-endogenously-generated-dna-base-modifications-with-isotope-dilution-two-dimensional-ultraperformance-liquid-chromatography-with-tandem-mass-spectrometry-possible-clinical-implication
#14
Daniel Gackowski, Marta Starczak, Ewelina Zarakowska, Martyna Modrzejewska, Anna Szpila, Zbigniew Banaszkiewicz, Ryszard Olinski
Our hereby presented methodology is suitable for reliable assessment of the most common unavoidable DNA modifications which arise as a product of fundamental metabolic processes. 8-Oxoguanine, one of the oxidatively modified DNA bases, is a typical biomarker of oxidative stress. A noncanonical base, uracil, may be also present in small quantities in DNA. A set of ten-eleven translocation (TET) proteins are involved in oxidation of 5-methylcytosine to 5-hydroxymethylcytosine which can be further oxidized to 5-formylcytosine and 5-carboxycytosine...
December 20, 2016: Analytical Chemistry
https://www.readbyqxmd.com/read/28192997/photolysis-of-antibiotics-under-simulated-sunlight-irradiation-identification-of-photoproducts-by-high-resolution-mass-spectrometry
#15
Rosa María Baena-Nogueras, Eduardo Gonzalez-Mazo, Pablo Antonio Lara-Martín
There is a growing concern on the widespread use of antibiotics and their presence in the aqueous environment. Their removal in the water column is mediated by different types of degradation processes for which the mechanisms are still unclear. This research is focused on characterizing the photodegradation kinetics and pathways of two largely employed antibiotics families: sulfonamides (9 SDs) and fluoroquinolones (6 FQs). Degradation percentages and rates were measured in pure water exposed to simulated natural sunlight at a constant irradiance value (500 W m-2) during all the experiments, and the main photoproducts formed were characterized through accurate mass measurement using ultra-performance liquid chromatography - quadrupole-time-of-flight - mass spectrometry (UPLC-QToF-MS)...
February 14, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28192976/quantification-of-influenza-neuraminidase-activity-by-ultra-high-performance-liquid-chromatography-and-isotope-dilution-mass-spectrometry
#16
Maria I Solano, Adrian R Woolfitt, Tracie L Williams, Carrie L Pierce, Larisa V Gubareva, Vasiliy Mishin, John Robert Barr
Mounting evidence suggests that neuraminidase's functionality extends beyond its classical role in influenza virus infection and that anti-neuraminidase antibodies offer protective immunity. Therefore, a renewed interest in development of neuraminidase (NA)-specific methods to characterize the glycoprotein and evaluate potential advantages for NA standardization in influenza vaccines has emerged. NA displays sialidase activity by cleaving off the terminal N-acetylneuraminic acid on α-2-3 or α-2-6 sialic acid containing receptors of host cells...
February 6, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28192719/hplc-ms-ms-method-for-the-simultaneous-quantification-of-desmethylmebeverine-acid-mebeverine-acid-and-mebeverine-alcohol-in-human-plasma-along-with-its-application-to-a-pharmacokinetics-study
#17
Natalia E Moskaleva, Pavel A Baranov, Natalia V Mesonzhnik, Svetlana A Appolonova
A new simple, rapid and sensitive high pressure liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed and validated for simultaneous analysis of mebeverine metabolites as: mebeverine alcohol (MAL), mebeverine acid (MAC) and desmethylmebeverine acid (DMAC) in human plasma. Sample preparation was performed by protein precipitation following the separation of analytes using an Acquity UPLC BEN C8 column 1.7 mm 2.1×50mm (Waters, USA). (2)H5-desmethylmebeverine acid ((2)H5-DMAC) was used as the internal standard (IS)...
February 6, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28191971/cultures-of-the-marine-bacterium-pseudovibrio-denitrificans-ab134-produce-bromotyrosine-derived-alkaloids-previously-only-isolated-from-marine-sponges
#18
Karen J Nicacio, Laura P Ióca, Adriana M Fróes, Luciana Leomil, Luciana R Appolinario, Christiane C Thompson, Fabiano L Thompson, Antonio G Ferreira, David E Williams, Raymond J Andersen, Alessandra S Eustaquio, Roberto G S Berlinck
Herein we report the isolation and spectroscopic identification of fistularin-3 (1), 11-hydroxyaerothionin (2), and verongidoic acid (3), as well as the UPLC-HRMS detection of aerothionin (4), homopurpuroceratic acid B (5), purealidin L (6), and aplysinamisine II (7), from cultures of the marine bacterium Pseudovibrio denitrificans Ab134, isolated from tissues of the marine sponge Arenosclera brasiliensis. These results unambiguously demonstrate for the first time that bromotyrosine-derived alkaloids that were previously isolated only from Verongida sponges can be biosynthesized by a marine bacterium...
February 13, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28191951/rearranged-terpenoids-from-the-marine-sponge-darwinella-cf-oxeata-and-its-predator-the-nudibranch-felimida-grahami
#19
Maria Camila A Ramirez, David E Williams, Juliana R Gubiani, Lizbeth L L Parra, Mario F C Santos, Daiane D Ferreira, Juliana T Mesquita, Andre G Tempone, Antonio G Ferreira, Vinícius Padula, Eduardo Hajdu, Raymond J Andersen, Roberto G S Berlinck
Marine sponges are a rich source of terpenoids with rearranged spongian carbon skeletons. Investigation of extracts from the sponge Darwinella cf. oxeata yielded four new rearranged diterpenoids, oxeatine (2) and oxeatamides H-J (3-5), as well as the known metabolites oxeatamide A (6), oxeatamide A methyl ester (7), and membranolide (1). Oxeatine (2) has a new heterocyclic skeleton, while oxeatamide J (5) has an N-methyl urea group included in a γ-lactam moiety. UPLC-QTOF analysis of the extract obtained from the mantle of the nudibranch Felimida grahami indicated the presence of 1 and 4...
February 13, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28191939/phytochemical-profiles-of-new-red-fleshed-apple-varieties-compared-with-traditional-and-new-white-fleshed-varieties
#20
David Bars-Cortina, Alba Macià, Ignasi Iglesias, Maria Paz Romero, Maria José Motilva
This study is an exhaustive chemical characterization of the phenolic compounds, triterpenes, and organic and ascorbic acids in red-fleshed apple varieties obtained by different breeding programs and using five traditional and new white-fleshed apple cultivars as reference. To carry out these analyses, solid-liquid extraction (SLE) and ultraperformance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) were used. The results showed that the red-fleshed apples contained, in either the flesh or peel, higher amounts of phenolic acids (chlorogenic acid), anthocyanins (cyanidin-3-O-galactoside), dihydrochalcones (phloretin xylosyl glucoside), and organic acids (malic acid) but a lower amount of flavan-3-ols than the white-fleshed apples...
February 13, 2017: Journal of Agricultural and Food Chemistry
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