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https://www.readbyqxmd.com/read/29168716/ozonation-for-the-removal-of-bisphenol-a
#1
Michael Emmanuel Mutseyekwa, Şifa Doğan, Saltuk Pirgalıoğlu
The mechanism of byproduct formation and oxidation pathway of bisphenol A (BPA) during ozonation process have been compared under acidic, neutral and alkaline conditions at an applied ozone dose of 5.3 mg·L(-1) min(-1). Alkaline conditions promoted the fastest removal and the pseudo first-order reaction rate constant was calculated as 0.15 min(-1). Complete removal under alkaline conditions (after 30 minutes of reaction time) was achieved with 1.59 mg ozone per mg BPA and 52% mineralization was achieved at 6...
November 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/29167413/occurrence-and-biological-activity-of-palmitoleic-acid-isomers-in-phagocytic-cells
#2
Alma M Astudillo, Clara Meana, Carlos Guijas, Laura Pereira, Patricia Lebrero, Maria A Balboa, Jesus Balsinde
Recent studies have highlighted the role of palmitoleic acid, cis-9-hexadecenoic acid (16:1n-7), as a lipid hormone that coordinates cross-talk between liver and adipose tissue, and exerts anti-inflammatory protective effects on hepatic steatosis and insulin signaling in murine models of metabolic disease. More recently, a palmitoleic acid isomer, cis-7-hexadecenoic acid (16:1n-9) that also possesses marked anti-inflammatory effects, has been described in human circulating monocytes and monocyte-derived macrophages...
November 21, 2017: Journal of Lipid Research
https://www.readbyqxmd.com/read/29167118/exercise-facilitates-early-recognition-of-cardiac-and-vascular-remodeling-in-chronic-thrombo-embolic-pulmonary-hypertension-in-a-novel-cteph-swine-model
#3
Kelly Stam, Richard W B van Duin, Andre Uitterdijk, Zongye Cai, Dirk J Duncker, Daphne Merkus
Chronic thrombo-embolic pulmonary hypertension (CTEPH) develops in 4% of patients after pulmonary embolism and is accompanied by an impaired exercise tolerance, which is ascribed to the increased right ventricular (RV) afterload and a ventilation/perfusion (V/Q) mismatch in the lungs. This study investigated changes in arterial PO2 and hemodynamics in response to graded treadmill exercise during development and progression of CTEPH in a swine model. Swine were chronically instrumented and received multiple pulmonary embolisms by (i) microsphere infusion (Spheres) over five weeks, (ii) endothelial dysfunction by administration of eNOS inhibitor L-N(ω)-Nitroarginine methyl ester (LNAME) during seven weeks, (iii) combined pulmonary embolisms and endothelial dysfunction (LNAME+Spheres), or (iv) served as sham-operated controls (Sham)...
November 22, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/29165495/electronic-structure-and-dynamics-of-torsion-locked-photoactive-yellow-protein-chromophores
#4
Alice Henley, Matus E Diveky, Anand M Patel, Michael A Parkes, James C Anderson, Helen H Fielding
The photocycle of photoactive yellow protein (PYP) begins with small-scale torsional motions of the chromophore leading to large-scale movements of the protein scaffold triggering a biological response. The role of single-bond torsional molecular motions of the chromophore in the initial steps of the PYP photocycle are not fully understood. Here, we employ anion photoelectron spectroscopy measurements and quantum chemistry calculations to investigate the electronic relaxation dynamics following photoexcitation of four model chromophores, para-coumaric acid, its methyl ester, and two analogues with aliphatic bridges hindering torsional motions around the single bonds adjacent to the alkene group...
November 22, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29164835/penile-erection-induced-by-scoparone-from-artemisia-capillaris-through-the-nitric-oxide-cyclic-guanosine-monophosphate-signaling-pathway
#5
Bo Ram Choi, Hye Kyung Kim, Jong Kwan Park
PURPOSE: The objective of this study was to evaluate the relaxant effect of scoparone from Artemisia capillaris on rabbit penile corpus cavernosum smooth muscle (PCCSM) and to elucidate the mechanism of action of scoparone for the treatment of erectile dysfunction (ED). MATERIALS AND METHODS: PCCSM that had been precontracted with phenylephrine was treated with 3 Artemisia herbs (A. princeps, A. capillaris, and A. iwayomogi) and 3 fractions (n-hexane, ethyl acetate, and n-butanol) with different concentrations (0...
November 21, 2017: World Journal of Men's Health
https://www.readbyqxmd.com/read/29160141/effects-of-mild-blast-traumatic-brain-injury-on-cerebral-vascular-histopathological-and-behavioral-outcomes-in-rats
#6
Uylissa A Rodriguez, Yaping Zeng, Donald James Deyo, Margaret O Parsley, Bridget E Hawkins, Donald S Prough, Douglas DeWitt
To determine the effects of mild blast-induced traumatic brain injury (bTBI), several groups of rats were subjected to blast injury or sham injury in a compressed air-driven shock tube. The effects of bTBI on relative cerebral perfusion (laser Doppler flowmetry, LDF), mean arterial blood pressure (MAP) cerebral vascular resistance were measured for two hrs post-bTBI. Dilator responses to reduced intravascular pressure were measured in isolated middle cerebral arterial (MCA) segments, ex vivo, 30 and 60 min post-bTBI...
November 21, 2017: Journal of Neurotrauma
https://www.readbyqxmd.com/read/29159730/uplc-elsd-analysis-of-algal-lipid-classes-and-derivatization-of-bound-and-free-fatty-acids-and-sterols-for-gc-ms-methods
#7
Tuulikki Seppänen-Laakso, Heli Nygren, Heiko Rischer
Constituents of microalgae and sample preparation for UPLC-ELSD and GC-MS analyses are described. Bound fatty acids from acylglycerols, alkylacylglycerols, galactosyldiacylglycerols, glycerophospholipids, and sterol esters are derivatized by using transesterification with sodium methoxide to form fatty acid methyl esters. Compounds containing free hydroxyl groups, either present originally or formed during previous step, like free fatty acids, sterols, α-tocopherol, phytol, and nonesterified alkoxyglycerols, are trimethylsilylated...
November 21, 2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/29155989/5-hydroxytryptamine-independent-antidepressant-actions-of-r-ketamine-in-a-chronic-social-defeat-stress-model
#8
Kai Zhang, Chao Dong, Yuko Fujita, Atsuhiro Fujita, Kenji Hashimoto
Background: Previous reports suggest that 5-hydroxytryptamine (5-HT) might play a role in the antidepressant actions of (R,S)-ketamine. However, its role in the antidepressant actions of (R)-ketamine, which is more potent than (S)-ketamine, is unknown. This study was conducted to examine whether 5-HT depletion affects the antidepressant actions of (R)-ketamine in a chronic social defeat stress (CSDS) model. Methods: An inhibitor of 5-HT synthesis, para-chlorophenylalanine methyl ester hydrochloride (PCPA; 300 mg/kg, twice daily for 3 consecutive days), or vehicle was administered to control and CSDS susceptible mice...
November 16, 2017: International Journal of Neuropsychopharmacology
https://www.readbyqxmd.com/read/29155489/priming-of-cowpea-volatile-emissions-with-defense-inducers-enhances-the-plant-s-attractiveness-to-parasitoids-when-attacked-by-caterpillars
#9
Islam S Sobhy, Toby J A Bruce, Ted C J Turlings
BACKGROUND: The manipulation of herbivore-induced volatile organic compounds (HI-VOCs) via the application of the inducers BTH [benzo (1,2,3) thiadiazole-7-carbothioic acid S-methyl ester] and Laminarin [β-1,3-glucan] is known to enhance the attractiveness of caterpillar-damaged cotton and maize plants to parasitoids. To test if this is also the case for legumes, we treated cowpea with these inducers and studied the effects on HI-VOC emissions and the attraction of three generalist endoparasitoids...
November 20, 2017: Pest Management Science
https://www.readbyqxmd.com/read/29155357/rifm-fragrance-ingredient-safety-assessment-cyclohexanecarboxylic-acid-1-4-dimethyl-methyl-ester-trans-cas-registry-number-23250-42-2
#10
A M Api, D Belsito, D Botelho, D Browne, M Bruze, G A Burton, J Buschmann, M L Dagli, M Date, W Dekant, C Deodhar, M Francis, A D Fryer, K Joshi, S L A Cava, A Lapczynski, D C Liebler, D O'brien, R Parakhia, A Patel, T M Penning, G Ritacco, J Romine, D Salvito, T W Schultz, I G Sipes, Y Thakkar, E H Theophilus, A K Tiethof, Y Tokura, S Tsang, J Wahler
No abstract text is available yet for this article.
November 16, 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/29154865/serrulatic-acid-diastereomers-identified-from-an-antibacterial-survey-of-eremophila
#11
Dane Lyddiard, Ben W Greatrex
In an age of growing antimicrobial resistance, new antibacterial agents are desperately needed. A rapid antibacterial and phytochemical survey was designed to screen for antibacterial leads in plants. The survey was applied to over 90 Australian native plants from the genus Eremophila, revealing Eremophila complanata and E. nivea×E. drummondii as active against Gram positive bacteria. Thin layer chromatography with bioautography, flash chromatography and nuclear magnetic resonance led to the isolation and identification of two diastereomeric serrulatic acids...
November 14, 2017: Fitoterapia
https://www.readbyqxmd.com/read/29152797/oxidative-stress-does-not-influence-local-sweat-rate-during-high-intensity-exercise
#12
Robert D Meade, Naoto Fujii, Martin P Poirier, Pierre Boulay, Ronald J Sigal, Glen P Kenny
Nitric oxide (NO)-dependent sweating is diminished during high but not moderate intensity exercise. We evaluated whether this impairment stems from increased oxidative stress during high intensity exercise. On two separate days, 11 young (24 ± 4 years) males cycled in the heat (35°C) at a moderate (500 W; 52 ± 6%VO2peak ) or high (700 W; 71 ± 5%VO2peak ) rate of metabolic heat production. Each session included two 30-min exercise bouts separated by a 20-min recovery. Local sweat rate was monitored at four forearm skin sites continuously perfused via intradermal microdialysis with: (1) lactated Ringer's solution (Control), (2) 10 mm ascorbate (Ascorbate; non-selective antioxidant), (3) 10 mm N(G) -nitro-L -arginine methyl ester (L-NAME; NO synthase inhibitor), or (4) 10 mm Ascorbate + 10 mm L-NAME (Ascorbate + L-NAME)...
November 19, 2017: Experimental Physiology
https://www.readbyqxmd.com/read/29152050/consequences-of-depsipeptide-substitution-on-the-clpp-activation-activity-of-antibacterial-acyldepsipeptides
#13
Yangxiong Li, Nathan P Lavey, Jesse A Coker, Jessica E Knobbe, Dat C Truong, Hongtao Yu, Yu-Shan Lin, Susan L Nimmo, Adam S Duerfeldt
The acyldepsipeptide (ADEP) antibiotics operate through a clinically unexploited mechanism of action and thus have attracted attention from several antibacterial development groups. The ADEP scaffold is synthetically tractable, and deep-seated modifications have produced extremely potent antibacterial leads against Gram-positive pathogens. Although newly identified ADEP analogs demonstrate remarkable antibacterial activity against bacterial isolates and in mouse models of bacterial infections, stability issues pertaining to the depsipeptide core remain...
November 9, 2017: ACS Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/29150927/identification-of-proteins-drying-oils-waxes-and-resins-in-the-works-of-art-micro-samples-by-chromatographic-and-mass-spectrometric-techniques
#14
Bartłomiej Witkowski, Anna Duchnowicz, Monika Ganeczko, Agnieszka Laudy, Tomasz Gierczak, Magdalena Biesaga
Simplified method for simultaneous identification of proteins, drying oils, waxes and resins in the works-of-art samples was developed. Liquid chromatography with mass spectrometry and gas chromatography with mass spectrometry were used to identify natural materials most frequently encountered in historical paintings. Protein binders were extracted with ammonia and purified using miniaturized solid-phase microextraction (Omix tips) to efficiently suppress matrix interferences. Zwitterionic stationary phase was used for separation of sixteen underivatized amino acids analysis with hydrophilic interaction liquid chromatography that were subsequently quantified with liquid chromatography with mass spectrometry...
November 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29148774/the-atmospheric-oxidation-of-furan-and-methyl-substituted-furans-initiated-by-hydroxyl-radicals
#15
Yi Yuan, Xiaocan Zhao, Sainan Wang, Liming Wang
Atmospheric oxidation mechanism of furan and methyl furans (MFs) initiated by OH radicals is studied using high-level quantum chemistry and kinetic calculations. The reaction starts mainly with OH addition to C2/C5-position, forming highly chemically activated adduct radical R2*/R5*, which would either be stabilized by collision or promptly isomerize to R2B*/R5B* by breaking the C2-O/C5-O bond and then isomerize to other conformers of R2B/R5B by internal rotations. Under the atmospheric conditions, the ring-retaining radical R2/R5 would recombine with O2 and be converted to a 5-hydroxy-2-furanone compound and a compound containing epoxide, ester, and carbonyl functional groups, while the ring-opening radicals R2B/R5B would react with O2 and form unsaturated 1,4-dicarbonyl compounds...
November 17, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/29148362/pseudomonas-floridensis-sp-nov-a-bacterial-pathogen-isolated-from-tomato
#16
Sujan Timilsina, Gerald V Minsavage, James Preston, Eric A Newberry, Matthews L Paret, Erica M Goss, Jeffrey B Jones, Gary E Vallad
An unusual fluorescent pseudomonad was isolated from tomato exhibiting leaf spot symptoms similar to bacterial speck. Strains were fluorescent, oxidase- and arginine-dihydrolase-negative, elicited a hypersensitive reaction on tobacco and produced a soft rot on potato slices. However, the strains produced an unusual yellow, mucoid growth on media containing 5 % sucrose that is not typical of levan. Based on multilocus sequence analysis using 16S rRNA, gap1, gltA, gyrB and rpoD, these strains formed a distinct phylogenetic group in the genus Pseudomonas and were most closely related to Pseudomonas viridiflava within the Pseudomonassyringae complex...
November 17, 2017: International Journal of Systematic and Evolutionary Microbiology
https://www.readbyqxmd.com/read/29147516/a-new-route-to-n-aromatic-heterocycles-from-the-hydrogenation-of-diesters-in-the-presence-of-anilines
#17
Yiping Shi, Paul C J Kamer, David J Cole-Hamilton, Michelle Harvie, Emma F Baxter, Kate J C Lim, Peter Pogorzelec
The hydrogenation of dicarboxylic acids and their esters in the presence of anilines provides a new synthesis of heterocycles. [Ru(acac)3] and 1,1,1-tris(diphenylphosphinomethyl)ethane (triphos) gave good to excellent yields of the cyclic amines at 220 °C. When aqueous ammonia was used with dimethyl 1,6-hexadienoic acid, ε-caprolactam was obtained in good yield. A side reaction involving alkylation of the amine by methanol was suppressed by using diesters derived from longer chain and branched alcohols. Hydrogenation of optically pure diesters (dimethyl (R)-2-methylbutanedioate and dimethyl (S)-2-methylbutanedioate) with aniline afforded racemic 3-methyl-1-phenylpyrrolidine in 78% yield...
October 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/29144385/preparation-and-characterization-of-cellulose-triacetate-as-support-for-lecitase-ultra-immobilization
#18
Francielle Batista da Silva, Wilson Galvão de Morais Júnior, Cleuzilene Vieira da Silva, Andressa Tironi Vieira, Antônio Carlos Ferreira Batista, Anízio Márcio de Faria, Rosana Maria Nascimento Assunção
The use of polymers as supports for enzyme immobilization is a strategy that enables to remove the enzymes from a chemical reaction and improve their efficiency in catalytic processes. In this work, cellulose triacetate (CTA) was used for physical adsorption of phospholipase Lecitase ultra (LU). CTA is more hydrophobic than cellulose, shows good performance in the lipases immobilization being a good candidate for immobilization of phospholipases. We investigated the immobilization of LU in CTA, the stability of the immobilized enzyme (CTA-LU) and the performance of CTA-LU using soybean oil as a substrate...
November 16, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29143841/ionic-liquids-as-stationary-phases-for-fatty-acid-analysis-by-gas-chromatography
#19
REVIEW
C Fanali, G Micalizzi, P Dugo, L Mondello
The present paper provides an overview of the application of ionic liquid (IL) columns for GC analysis of fatty acid methyl esters (FAMEs). Although their separation can be carried out utilizing GC columns containing polar stationary phases, some ILs have been employed as stationary phases, either commercial or laboratory made, in GC analysis. Monodimensional and bidimensional GC methods have been optimized in order to achieve the best separation especially considering the geometric and positional isomers of unsaturated fatty acids...
November 16, 2017: Analyst
https://www.readbyqxmd.com/read/29143535/cytotoxic-triterpene-saponins-from-the-mangrove-aegiceras-corniculatum
#20
Le Ba Vinh, Nguyen Thi Minh Nguyet, Seo Young Yang, Jang Hoon Kim, Nguyen Van Thanh, Nguyen Xuan Cuong, Nguyen Hoai Nam, Chau Van Minh, Inkyu Hwang, Young Ho Kim
Using various chromatographic separations, sixteen compounds, including one new triterpene saponin named aegicoroside A (1), were isolated from the leaves of the Vietnamese mangrove Aegiceras corniculatum. Their structures were determined by spectroscopic methods such as 1D and 2D NMR and HR-ESI-MS. The cytotoxic activities of the isolated compounds against MCF7 (breast), HCT116 (colon), B16F10 (melanoma), and A549 (adenocarcinoma) cancer cell lines were also evaluated. Strong cytotoxicity was observed for sakurasosaponin (2) against all four cancer cell lines and for sakurasosaponin methyl ester (3) against MCF7, A549, and HCT116 cell lines with IC50 values ranging from 2...
November 16, 2017: Natural Product Research
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