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https://www.readbyqxmd.com/read/29130161/detection-of-2-alkyl-4-quinolones-using-biosensors
#1
Matthew P Fletcher, Stephen P Diggle, Miguel Cámara, Paul Williams
2-Alkyl-4-quinolones (AQs) such as 2-heptyl-3-hydroxy-4-quinolone (PQS) and 2-heptyl-4-hydroxyquinoline (HHQ) are quorum-sensing signal molecules. Here we describe two methods for AQ detection and quantification that employ thin-layer chromatography (TLC) and microtiter plate assays in combination with a lux-based Pseudomonas aeruginosa AQ biosensor strain. For TLC detection, organic solvent extracts of bacterial cells or spent culture supernatants are chromatographed on TLC plates, which are then dried and overlaid with the AQ biosensor...
2018: Methods in Molecular Biology
https://www.readbyqxmd.com/read/29115023/secondary-queens-in-the-parthenogenetic-termite-cavitermes-tuberosus-develop-through-a-transitional-helper-stage
#2
Simon Hellemans, Denis Fournier, Robert Hanus, Yves Roisin
In termite species with asexual queen succession (AQS), parthenogenetically produced immatures mostly differentiate into secondary queens, called "neotenics." In order to elucidate the ontogenetic origin of neotenics in Cavitermes tuberosus (Termitidae: Termitinae), a neotropical termite with AQS, we investigated developmental pathways of offspring according to their sex and genetic origin using both morphometric and genetic tools. The caste system of C. tuberosus follows the classical pathway of Termitidae...
November 2017: Evolution & Development
https://www.readbyqxmd.com/read/29091715/antiquorum-sensing-antibiofilm-formation-and-cytotoxicity-activity-of-commonly-used-medicinal-plants-by-inhabitants-of-borabu-sub-county-nyamira-county-kenya
#3
Eric Omori Omwenga, Andreas Hensel, Susana Pereira, Alfred Anakalo Shitandi, Francisco M Goycoolea
Productions of various bacterial traits like production of virulence factors (e.g. toxins, enzymes), biofilm formation, luminescence among others, have been known to be controlled by quorum sensing (QS), a process that is dependent on chemical signals or autoinducers (AIs). Bacteria known to rely on such AIs are known to be virulent and tend to be resistant against various antimicrobial agents. Therefore, strategies aimed at the inhibition of QS pathways, are regarded as potential novel therapies in managing bacterial virulence hence reducing their ability to induce infections in humans...
2017: PloS One
https://www.readbyqxmd.com/read/29062001/combined-tddft-and-aim-insights-into-photoinduced-excited-state-intramolecular-proton-transfer-esipt-mechanism-in-hydroxyl-and-amino-anthraquinone-solution
#4
Daoyuan Zheng, Mingzhen Zhang, Guangjiu Zhao
Time-dependent density functional theory (TDDFT) and atoms in molecules (AIM) theory are combined to study the photoinduced excited state intramolecular proton transfer (ESIPT) dynamics for eight anthraquinones (AQs) derivatives in solution. The calculated absorption and emission spectra are consistent with the available experimental data, verifying the suitability of the theory selected. The systems with the excited-state exothermic proton transfer, such as 1-HAQ, 1,5-DHAQ and TFAQ, emit completely from transfer structure (T), while the reactions for those without ESIPT including 1,4-DHAQ and AAAQ appear to be endothermic...
October 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29042953/oral-colon-specific-drug-delivery-system-reduces-the-nephrotoxicity-of-rhubarb-anthraquinones-when-they-produce-purgative-efficacy
#5
Pei Liu, Hongwei Wei, Jinhua Chang, Guangxin Miao, Xigang Liu, Zhongsi Li, Liyan Liu, Xiangrong Zhang, Cuizhe Liu
Rhubarb is commonly used to treat constipation in China and anthraquinones (AQs) are the active components present in rhubarb. However, an increasing number of studies have reported that AQs induce nephrotoxicity. In the present study, rhubarb total free anthraquinones (RTFA) oral colon-specific drug delivery granules (RTFA-OCDD-GN) were prepared to determine whether RTFA-OCDD-GN could reduce the nephrotoxicity that occurs when AQs produce purgative efficacy. RTFA-OCDD-GN were prepared using pH-enzyme double-layer coating technology and the cumulative release rate of RTFA in RTFA-OCDD-GN was assessed...
October 2017: Experimental and Therapeutic Medicine
https://www.readbyqxmd.com/read/28865375/dramatic-enhancement-of-organics-degradation-and-electricity-generation-via-strengthening-superoxide-radical-by-using-a-novel-3d-aqs-ppy-gf-cathode
#6
Yan Zhang, Jinhua Li, Jing Bai, Linsen Li, Ligang Xia, Shuai Chen, Baoxue Zhou
A dramatic enhancement of organics degradation and electricity generation has been achieved in a wastewater fuel cell (WFC) system via strengthening superoxide radical with radical chain reaction by using a novel 3D anthraquinone/polypyrrole modified graphite felt (AQS/PPy-GF) cathode. The AQS/PPy-GF was synthesized by one-pot electrochemical polymerization method and used to in-situ generate superoxide radical by reducing oxygen under self-imposed electric field. Results showed that methyl orange (MO) were effectively degraded in AQS/PPy-GF/Fe(2+) system with a high apparent rate constant (0...
November 15, 2017: Water Research
https://www.readbyqxmd.com/read/28800554/anthraquinone-2-sulfonate-immobilized-to-conductive-polypyrrole-hydrogel-as-a-bioanode-to-enhance-power-production-in-microbial-fuel-cell
#7
Xinhua Tang, How Yong Ng
In this study, anthraquinone-2-sulfonate (AQS), a redox mediator, was covalently bound to conductive polypyrrole hydrogel (CPH) via electrochemical reduction of the in-situ-generated AQS diazonium salts. The porous structure and hydrophilic surface of this CPH/AQS anode enhanced biofilm formation while the AQS bound on the CPH/AQS anode worked as a redox mediator. The CPH/AQS bioanode reduced the charge transfer resistance from 28.3Ω to 4.1Ω while increased the maximum power density from 762±37mW/m(2) to 1919±69mW/m(2), compared with the bare anode...
November 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28772219/poly-d-l-lactide-co-glycolide-nanoparticles-for-sustained-release-of-tacrolimus-in-rabbit-eyes
#8
Mohd Abul Kalam, Aws Alshamsan
Tacrolimus (TAC)-loaded Ploy-lactide-co-glycolide nanoparticles (PLGA-NPs) was developed by emulsification-diffusion method for topical ocular delivery in certain ocular conditions where therapeutic level of immunomodulator into eyes is required for sufficient duration. So, we optimized TAC-loaded PLGA-NPs with higher TAC payload. The mean particle-size and its distribution, polydispersity, zeta-potentials, morphology, drug encapsulation and loading capacity of NPs were analyzed. Transcorneal permeation through excised rabbit cornea revealed instant and controlled permeation of TAC from TAC-aqueous suspension (TAC-AqS) and from PLGA-NPs, respectively...
October 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28763730/fine-particulate-matter-and-cardiovascular-disease-comparison-of-assessment-methods-for-long-term-exposure
#9
COMPARATIVE STUDY
Laura A McGuinn, Cavin Ward-Caviness, Lucas M Neas, Alexandra Schneider, Qian Di, Alexandra Chudnovsky, Joel Schwartz, Petros Koutrakis, Armistead G Russell, Val Garcia, William E Kraus, Elizabeth R Hauser, Wayne Cascio, David Diaz-Sanchez, Robert B Devlin
BACKGROUND: Adverse cardiovascular events have been linked with PM2.5 exposure obtained primarily from air quality monitors, which rarely co-locate with participant residences. Modeled PM2.5 predictions at finer resolution may more accurately predict residential exposure; however few studies have compared results across different exposure assessment methods. METHODS: We utilized a cohort of 5679 patients who had undergone a cardiac catheterization between 2002-2009 and resided in NC...
November 2017: Environmental Research
https://www.readbyqxmd.com/read/28745519/an-optimized-protocol-for-anthraquinones-isolation-from-rhamnus-frangula-l
#10
Renato Sonchini Gonçalves, Expedito Leite Silva, Noboru Hioka, Celso Vataru Nakamura, Marcos Luciano Bruschi, Wilker Caetano
Different from works described in the literature, which use expansive analytical methods to separation of anthraquinones derivatives (AQs), this communication reported a simple and inexpensive methodology to get them. In this way, the expensive commercial AQs: Chrysophanol, physcione and emodine were extracted from plant material (Rhamnus frangula L.) and isolated by classical column chromatography technique under optimised binary mobile phase gradients (CHCl3 : AcOEt(a), a = 1 to 5%) in excellent yields.
July 26, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28729838/detection-of-emodin-derived-glutathione-adduct-in-normal-rats-administered-with-large-dosage-of-polygoni-multiflori-radix
#11
Li-Long Jiang, Dong-Sheng Zhao, Ya-Xi Fan, Qiong Yu, Ping Li, Hui-Jun Li
Polygoni Multiflori Radix (PMR) has been commonly used as a tonic in China for centuries. PMR-associated hepatotoxicity has been drawing increasingly more attention in recent years in parallel with its wide utilization. Anthraquinones (AQs) are recognized as the main hepatotoxic components in PMR. However, the exact underlying mechanism of AQs poisoning is still not fully understood. Herein, we proposed a hypothesis that metabolic activation of AQs such as emodin was involved in PMR-induced liver injury, AQs followed to generate the electrophilic reactive metabolites and subsequently formed covalent adduct with cellular nucleophiles in the liver to exert hepatotoxicity...
2017: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/28723923/on-the-mechanism-of-candida-tropicalis-biofilm-reduction-by-the-combined-action-of-naturally-occurring-anthraquinones-and-blue-light
#12
Juliana Marioni, Roger Bresolí-Obach, Montserrat Agut, Laura R Comini, José L Cabrera, María G Paraje, Santi Nonell, Susana C Núñez Montoya
The photoprocesses involved in the photo-induced Candida tropicalis biofilm reduction by two natural anthraquinones (AQs), rubiadin (1) and rubiadin-1-methyl ether (2), were examined. Production of singlet oxygen (1O2) and of superoxide radical anion (O2•-) was studied. Although it was not possible to detect the triplet state absorption of any AQs in biofilms, observation of 1O2 phosphorescence incubated with deuterated Phosphate Buffer Solution, indicated that this species is actually formed in biofilms...
2017: PloS One
https://www.readbyqxmd.com/read/28718968/the-design-of-the-mbt-g-adherence-and-quality-scale
#13
Espen J Folmo, Sigmund W Karterud, Kjetil Bremer, Kristoffer L Walther, Elfrida H Kvarstein, Geir A F Pedersen
Few group psychotherapy studies focus on therapists' interventions, and instruments that can measure group psychotherapy treatment fidelity are scarce. The aim of the present study was to evaluate the reliability of the Mentalization-based Group Therapy Adherence and Quality Scale (MBT-G-AQS), which is a 19-item scale developed to measure adherence and quality in mentalization-based group therapy (MBT-G). Eight MBT groups and eight psychodynamic groups (a total of 16 videotaped therapy sessions) were rated independently by five raters...
August 2017: Scandinavian Journal of Psychology
https://www.readbyqxmd.com/read/28685373/temperature-dependence-of-1-h-nmr-chemical-shifts-and-its-influence-on-estimated-metabolite-concentrations
#14
Felizitas C Wermter, Nico Mitschke, Christian Bock, Wolfgang Dreher
OBJECTIVES: Temperature dependent chemical shifts of important brain metabolites measured by localised (1)H MRS were investigated to test how the use of incorrect prior knowledge on chemical shifts impairs the quantification of metabolite concentrations. MATERIALS AND METHODS: Phantom measurements on solutions containing 11 metabolites were performed on a 7 T scanner between 1 and 43 °C. The temperature dependence of the chemical shift differences was fitted by a linear model...
July 6, 2017: Magma
https://www.readbyqxmd.com/read/28660582/single-step-capture-and-targeted-metabolomics-of-alkyl-quinolones-in-outer-membrane-vesicles-of-pseudomonas-aeruginosa
#15
Pallavi Lahiri, Dipankar Ghosh
Outer membrane vesicles (OMVs) are secreted by all Gram-ve pathogens. These nano-scale delivery vehicles contain discrete arrays of prokaryotic pathogenic determinants, including a family of low molecular weight (MW) lipidic quorum signaling alkyl-quinolones (AQs). These are synthesized from β-keto-fatty acids and function like primordial lipidic hormones, which regulate numerous pathogenic factors both inter-species and intra-species. Significantly, AQs can also directly exacerbate pathogenesis by cross-kingdom signaling with the host immune, metabolic, and other systems...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28570877/quinone-functionalized-activated-carbon-improves-the-reduction-of-congo-red-coupled-to-the-removal-of-p-cresol-in-a-uasb-reactor
#16
Luis H Alvarez, Iris C Arvizu, Refugio Bernardo García-Reyes, Claudia M Martinez, Daniel Olivo-Alanis, Yair A Del Angel
In this research was immobilized anthraquinone-2-sulfonate (AQS) on granular activated carbon (GAC) to evaluate its capacity to reduce congo red (CR) in batch reactor and continuous UASB reactors. The removal of p-cresol coupled to the reduction of CR was also evaluated. Results show that the immobilization of AQS on GAC (GAC-AQS) achieved 0.469mmol/g, improving 2.85-times the electron-transferring capacity compared to unmodified GAC. In batch, incubations with GAC-AQS achieved a rate of decolorization of 2...
May 19, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28547992/spatial-and-temporal-variations-in-characteristic-ratios-of-elemental-carbon-to-carbon-monoxide-and-nitrogen-oxides-across-the-united-states
#17
Aishwarya Raman, Avelino F Arellano
A ratio-based method is used to characterize anthropogenic elemental carbon (ECa) using in situ measurements and emissions of carbon monoxide (CO) and nitrogen oxides (NOx). We use long-term records of ground-based measurements from the U.S. Environmental Protection Agency (EPA) Air Quality System and Interagency Monitoring of Protected Visual Environments to assess the patterns in anthropogenic combustion ratios (ΔECa/ΔCO and ΔECa/ΔNOx) across the U.S. Petroleum Administration for Defense Districts (PADD) regions for the years 2000-2015...
June 12, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28411241/2-alkylquinolone-alkaloid-biosynthesis-in-the-medicinal-plant-evodia-rutaecarpa-involves-collaboration-of-two-novel-type-iii-polyketide-synthases
#18
Takashi Matsui, Takeshi Kodama, Takahiro Mori, Tetsuhiro Tadakoshi, Hiroshi Noguchi, Ikuro Abe, Hiroyuki Morita
2-Alkylquinolone (2AQ) alkaloids are pharmaceutically and biologically important natural products produced by both bacteria and plants, with a wide range of biological effects, including antibacterial, cytotoxic, anticholinesterase, and quorum-sensing signaling activities. These diverse activities and 2AQ occurrence in vastly different phyla have raised much interest in the biosynthesis pathways leading to their production. Previous studies in plants have suggested that type III polyketide synthases (PKSs) might be involved in 2AQ biosynthesis, but this hypothesis is untested...
June 2, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28287261/three-dimensional-encapsulation-of-saccharomyces-cerevisiae-in-silicate-matrices-creates-distinct-metabolic-states-as-revealed-by-gene-chip-analysis
#19
Zeeshan Fazal, Jennifer Pelowitz, Patrick E Johnson, Jason C Harper, C Jeffrey Brinker, Eric Jakobsson
In order to design hybrid cellular/synthetic devices such as sensors and vaccines, it is important to understand how the metabolic state of living cells changes upon physical confinement within three-dimensional (3D) matrices. We analyze the gene expression patterns of stationary phase Saccharomyces cerevisiae (S. cerevisiae) cells encapsulated within three distinct nanostructured silica matrices and relate those patterns to known naturally occurring metabolic states. Silica encapsulation methods employed were lipid-templated mesophase silica thin films formed by cell-directed assembly (CDA), lipid-templated mesophase silica particles formed by spray drying (SD), and glycerol-doped silica gel monoliths prepared from an aqueous silicate (AqS+g) precursor solution...
April 25, 2017: ACS Nano
https://www.readbyqxmd.com/read/28281327/asexual-queen-succession-mediates-an-accelerated-colony-life-cycle-in-the-termite-silvestritermes-minutus
#20
R Fougeyrollas, J Křivánek, V Roy, K Dolejšová, S Frechault, Y Roisin, R Hanus, D Sillam-Dussès
Mixed modes of reproduction, combining sexual processes with thelytokous parthenogenesis, occur in all major clades of social insects. In several species of termites, queens maximize their genetic input into nondispersing replacement queens through parthenogenesis, while maintaining genetically diverse sterile offspring and dispersing reproductives via sexual reproduction. This so-called asexual queen succession (AQS) has multiple independent origins and its presumed advantages are diverse as well, ranging from multiplication of colony reproductive potential to extension of its lifespan beyond that of the foundress...
June 2017: Molecular Ecology
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