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https://www.readbyqxmd.com/read/28214719/host-guest-interaction-of-3-hydroxyflavone-and-7-hydroxyflavone-with-cucurbit-7-uril-a-spectroscopic-and-calorimetric-approach
#1
Sayeed Ashique Ahmed, Banibrata Maity, Soma Seth Duley, Debabrata Seth
The modulation of photophysical behaviour of small organic molecules in the presence of macrocycles is one of the most interesting areas of research. In this work we reported the interaction of two biologically active molecules 3-hydroxyflavone and 7-hydroxyflavone with macrocyclic host cucurbit [7]uril in aqueous medium. To investigate the change of photophysical properties of these two flavones, we have used steady state absorption, fluorescence, time resolved fluorescence emission spectroscopy and isothermal titration calorimetric technique...
February 9, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28214676/chiral-aminoquinoline-based-fluorescent-ph-probe-with-large-stokes-shift-for-bioimaging
#2
Yong-Sheng Xie, Xin-Ling Zhang, Kun Xie, Yanmei Zhao, Huan Wu, Jidong Yang
The aminoquinoline derivatives, (R)- and (S)-2-phenyl-2-(quinolin-6-ylamino)ethan-1-ol (R-PEO and S-PEO), were synthesized by a tandem one-pot three-step CN coupling method where Smiles rearrangement was the key procedure. The selected compound R-PEO showed a significant fluorescence enhancement with a turn-on ratio over 98-fold and enabled the real time determination of proton concentration in acidic solution. The fluorescence intensity of R-PEO exhibited strong pH-dependent performance with a large Stokes shift (115nm) and responded linearly to minor pH change within the range of 3...
February 12, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28214542/several-hpept1-transported-drugs-are-substrates-of-the-e-coli-proton-coupled-oligopeptide-transporter-ydgr
#3
Bala K Prabhala, Nanda G Aduri, Mazhar Iqbal, Moazur Rahman, Michael Gajhede, Paul R Hansen, Osman Mirza
Proton-dependent oligopeptide transporters (POTs) are secondary active transporters found in all kingdoms of life. POTs utilize the proton electrochemical gradient for the uptake of nutrient dipeptides and tripeptides. The human POT hPepT1 is known to transport a number of drugs. As part of ongoing studies on substrate specificities of POTs from E. coli, our aim in this study was to investigate whether bacterial POTs could also transport these drugs. For this, we selected the common orally administered drugs sulpiride, bestatin, valacyclovir, ampicillin and oseltamivir, that are all transported by hPepT1...
February 15, 2017: Research in Microbiology
https://www.readbyqxmd.com/read/28214420/prevention-of-radiotherapy-induced-neurocognitive-dysfunction-in-survivors-of-paediatric-brain-tumours-the-potential-role-of-modern-imaging-and-radiotherapy-techniques
#4
REVIEW
Thankamma Ajithkumar, Stephen Price, Gail Horan, Amos Burke, Sarah Jefferies
Neurocognitive dysfunction is the leading cause of reduced quality of life in long-term survivors of paediatric brain tumours. Radiotherapy is one of the main contributors to neurocognitive sequelae. Current approaches for prevention and reduction of neurocognitive dysfunction include avoidance of radiotherapy in young children and reduction of the radiotherapy dose and volume of brain irradiated. Substantial advances have been made in brain imaging, especially with functional imaging and fibre tracking with the use of diffusion tensor imaging...
February 2017: Lancet Oncology
https://www.readbyqxmd.com/read/28214336/evidence-to-show-that-acetonitrile-is-sensitive-to-different-interactions-sites-of-ionic-liquids-as-unveiled-by-excess-spectroscopy
#5
Yu Zhou, Yan-Zhen Zheng, Tian Zhang, Geng Deng, Zhi-Wu Yu
By studying the interactions between an ionic liquid (IL), 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide ([Emim][Tf2N]) and a co-solvent acetonitrile, C≡N stretching vibration was found to be very sensitive to different interaction sites as unveiled by excess infrared spectroscopy. Four existing forms of acetonitrile molecules were identified and the detailed transformation process of the ionic liquid upon dilution was obtained. Such characteristic of nitrile group is discussed from the view point of its ability to form hydrogen bonds with proton donors...
February 18, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28214281/patient-characterization-and-usage-trends-of-proton-beam-therapy-for-localized-prostate-cancer-in-the-united-states-a-study-of-the-national-cancer-database
#6
Arya Amini, David Raben, E David Crawford, Thomas W Flaig, Elizabeth R Kessler, Elaine T Lam, Paul Maroni, Thomas J Pugh
PURPOSE: To evaluate usage trends and identify factors associated with proton beam therapy (PBT) compared to alternative forms of external beam radiation therapy (RT) (EBRT) for localized prostate cancer. PATIENTS AND METHODS: The National Cancer Database was queried for men with localized (N0, M0) prostate cancer diagnosed between 2004 and 2013, treated with EBRT, with available data on EBRT modality (photon vs. PBT). Binary multiple logistic regression identified variables associated with EBRT modality...
February 14, 2017: Urologic Oncology
https://www.readbyqxmd.com/read/28214150/self-efficacy-for-deprescribing-a-survey-for-health-care-professionals-using-evidence-based-deprescribing-guidelines
#7
Barbara Farrell, Lisa Richardson, Lalitha Raman-Wilms, David de Launay, Mhd Wasem Alsabbagh, James Conklin
BACKGROUND: Although polypharmacy is associated with significant morbidity, deprescribing can be challenging. In particular, clinicians express difficulty with their ability to deprescribe (i.e. reduce or stop medications that are potentially inappropriate). Evidence-based deprescribing guidelines are designed to help clinicians take action on reducing or stopping medications that may be causing more harm than benefit. OBJECTIVES: Determine if implementation of evidence-based guidelines increases self-efficacy for deprescribing proton pump inhibitor (PPI), benzodiazepine receptor agonist (BZRA) and antipsychotic (AP) drug classes...
January 28, 2017: Research in Social & Administrative Pharmacy: RSAP
https://www.readbyqxmd.com/read/28213877/improved-control-of-hypertension-following-laparoscopic-fundoplication-for-gastroesophageal-reflux-disease
#8
Zhiwei Hu, Meiping Chen, Jimin Wu, Qing Song, Chao Yan, Xing Du, Zhonggao Wang
This study aims to determine whether successful laparoscopic fundoplication for gastroesophageal reflux disease (GERD) can improve the control of hypertension. We conducted an observational study of GERD patients with hypertension. The esophageal and gastroesophageal symptoms of these patients were successfully treated with laparoscopic fundoplication, as measured by the reduced GERD symptoms and proton pump inhibitor consumption. A hypertension control scale was used to classify the use of antihypertensive medications and the quality of blood pressure control before and after anti-reflux surgery...
February 17, 2017: Frontiers of Medicine
https://www.readbyqxmd.com/read/28213527/advancing-viral-rna-structure-prediction-measuring-the-thermodynamics-of-pyrimidine-rich-internal-loops
#9
Andy Phan, Katherine Mailey, Jessica Sakai, Xiaobo Gu, Susan J Schroeder
Accurate thermodynamic parameters improve RNA structure predictions and thus accelerate understanding of RNA function and the identification of RNA drug binding sites. Many viral RNA structures, such as internal ribosome entry sites, have internal loops and bulges that are potential drug target sites. Current models used to predict internal loops are biased towards small, symmetric purine loops, and thus poorly predict asymmetric, pyrimidine-rich loops with more than 6 nucleotides that occur frequently in viral RNA...
February 17, 2017: RNA
https://www.readbyqxmd.com/read/28213258/p-aminothiophenol-coated-cdse-zns-quantum-dots-as-a-turn-on-fluorescent-probe-for-ph-detection-in-aqueous-media
#10
Dong Li, Hu Xu, Dan Li, Yuhong Wang
Since controlling hydrogen ion concentration (i.e. pH) is fairly important in various fields, developing a facile pH detection method is highly desired. Owing to the superior optical properties, semiconductor quantum dots (QDs) have been developed as a promising alternative for organic fluorophores in fluorescence analysis. In this study, a hydrophilic p-aminothiophenol (pATP) capped CdSe/ZnS QDs (denoted as pATP-QDs) as a selective "turn-on" fluorescence probe for pH in aqueous media is reported. The pATP-QDs probe easily obtained via ligand exchange are characterized by various analytic techniques including ultraviolet-visible, fourier transform infrared, fluorescence, time-resolved fluorescence spectroscopies, and transmission electron microscope etc...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28213048/low-field-single-sided-nmr-for-one-shot-1d-mapping-application-to-membranes
#11
Patrick Judeinstein, Filippo Ferdeghini, Rodrigo Oliveira-Silva, Jean-Marc Zanotti, Dimitrios Sakellariou
Many single-sided permanent magnet NMR systems have been proposed over the years allowing for 1D proton-density profiling, diffusion measurements and relaxometry. In this manuscript we make use of a recently published unilateral magnet for low-field NMR exhibiting an extremely uniform magnetic field gradient with moderate strength and cylindrical symmetry, allowing for a well-defined sweet spot. Combined with a goniometer, our system is used to characterize precisely the uniformity of its gradient and to achieve micrometric precision 1D profiling, as well as spatially localized relaxometry and diffusometry on thick (∼150μm) membrane samples...
February 8, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28213021/comparing-ptr-ms-profile-of-milk-inoculated-with-pure-or-mixed-cultures-of-spoilage-bacteria
#12
Mohammad Alothman, Karen A Lusk, Patrick Silcock, Phil J Bremer
The volatile organic compounds (VOCs) associated with UHT milk (n=8) inoculated with either pure inoculums of Pseudomonas fluorescens (two strains tested) or Chryseobacterium sp., or with mixed cultures of 2 or all 3 of the bacterial strains, and held at 4.5 °C for up to 26 days was measured using proton transfer reaction - mass spectrometry (PTR-MS). The VOCs evolved included a range of carbonyl compounds, alcohols, esters, and acids and had significant qualitative and quantitative differences between the inoculums...
June 2017: Food Microbiology
https://www.readbyqxmd.com/read/28212755/stimulating-central-carbon-metabolism-to-re-sensitize-pseudomonas-aeruginosa-to-aminoglycosides
#13
Dorival Martins, Dao Nguyen
In this issue of Cell Chemical Biology, Meylan et al. (2017) examine how stimulation of central carbon metabolism of Pseudomonas aeruginosa modulates aminoglycoside lethality in tolerant bacteria. They identify fumarate as a tobramycin potentiator that stimulates proton motive force-dependent drug uptake and increases respiration-dependent killing.
February 16, 2017: Cell Chemical Biology
https://www.readbyqxmd.com/read/28212705/detection-of-dna-damage-by-space-radiation-in-human-fibroblasts-flown-on-the-international-space-station
#14
Tao Lu, Ye Zhang, Michael Wong, Alan Feiveson, Ramona Gaza, Nicholas Stoffle, Huichen Wang, Bobby Wilson, Larry Rohde, Louis Stodieck, Fathi Karouia, Honglu Wu
Although charged particles in space have been detected with radiation detectors on board spacecraft since the discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation is challenging due to the low dose and low dose rate nature of the radiation environment, and due to the difficulty in distinguishing the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in their lymphocytes and early onset of cataracts, are attributed primarily to their exposure to space radiation...
February 2017: Life Sciences in Space Research
https://www.readbyqxmd.com/read/28212316/succinimide-formation-from-an-ngr-containing-cyclic-peptide-computational-evidence-for-catalytic-roles-of-phosphate-buffer-and-the-arginine-side-chain
#15
Ryota Kirikoshi, Noriyoshi Manabe, Ohgi Takahashi
The Asn-Gly-Arg (NGR) motif and its deamidation product isoAsp-Gly-Arg (isoDGR) have recently attracted considerable attention as tumor-targeting ligands. Because an NGR-containing peptide and the corresponding isoDGR-containing peptide target different receptors, the spontaneous NGR deamidation can be used in dual targeting strategies. It is well known that the Asn deamidation proceeds via a succinimide derivative. In the present study, we computationally investigated the mechanism of succinimide formation from a cyclic peptide, c[CH₂CO-NGRC]-NH₂, which has recently been shown to undergo rapid deamidation in a phosphate buffer...
February 16, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28212052/proton-density-fat-fraction-measurements-at-1-5-and-3-t-hepatic-mr-imaging-same-day-agreement-among-readers-and-across-two-imager-manufacturers
#16
Suraj D Serai, Jonathan R Dillman, Andrew T Trout
Purpose To determine the agreement of proton density fat fraction (PDFF) measurements obtained with hepatic magnetic resonance (MR) imaging among readers, imager manufacturers, and field strengths. Materials and Methods This HIPAA-compliant study was approved by the institutional review board. After providing informed consent, 24 adult volunteers underwent imaging with one 1.5-T MR unit (Ingenia; Philips Healthcare, Best, the Netherlands) and two different 3.0-T units (750 W [GE Healthcare, Waukesha, Wis] and Ingenia) on the same day to estimate hepatic PDFF...
February 24, 2017: Radiology
https://www.readbyqxmd.com/read/28212047/multimaterial-decomposition-algorithm-for-the-quantification-of-liver-fat-content-by-using-fast-kilovolt-peak-switching-dual-energy-ct-clinical-evaluation
#17
Tomoko Hyodo, Norihisa Yada, Masatoshi Hori, Osamu Maenishi, Peter Lamb, Kosuke Sasaki, Minori Onoda, Masatoshi Kudo, Teruhito Mochizuki, Takamichi Murakami
Purpose To assess the clinical accuracy and reproducibility of liver fat quantification with the multimaterial decomposition (MMD) algorithm, comparing the performance of MMD with that of magnetic resonance (MR) spectroscopy by using liver biopsy as the reference standard. Materials and Methods This prospective study was approved by the institutional ethics committee, and patients provided written informed consent. Thirty-three patients suspected of having hepatic steatosis underwent non-contrast material-enhanced and triple-phase dynamic contrast-enhanced dual-energy computed tomography (CT) (80 and 140 kVp) and single-voxel proton MR spectroscopy within 30 days before liver biopsy...
February 17, 2017: Radiology
https://www.readbyqxmd.com/read/28212040/synthesis-and-speciation-dependent-properties-of-a-multimetallic-model-complex-of-nisod-that-exhibits-unique-hydrogen-bonding
#18
Ramsey A Steiner, Stephen P Dzul, Timothy L Stemmler, Todd C Harrop
The complex Na3[{Ni(II)(nmp)}3S3BTA(alk))] (1) (nmp(2-) = deprotonated form of N-(2-mercaptoethyl)picolinamide; H3S3BTA(alk) = N(1),N(3),N(5)-tris(2-mercaptoethyl)benzene-1,3,5-tricarboxamide, where H = dissociable protons), supported by the thiolate-benzenetricarboxamide scaffold (S3BTA(alk)), has been synthesized as a trimetallic model of nickel-containing superoxide dismutase (NiSOD). X-ray absorption spectroscopy (XAS) and (1)H NMR measurements on 1 indicate that the Ni(II) centers are square-planar with N2S2 coordination, and Ni-N and Ni-S distances of 1...
February 17, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28212031/bond-activation-and-hydrogen-evolution-from-water-through-reactions-with-m3s4-m-mo-w-and-w3s3-anionic-clusters
#19
Corrine A Kumar, Arjun Saha, Krishnan Raghavachari
Transition metal sulfides (TMS) are being investigated with increased frequency because of their ability to efficiently catalyze the hydrogen evolution reaction. We have studied the trimetallic TMS cluster ions, Mo3S4(-), W3S4(-), and W3S3(-), and probed their efficiency for bond activation and hydrogen evolution from water. These clusters have geometries that are related to the edge sites on bulk MoS2 surfaces that are known to play a role in hydrogen evolution. Using density functional theory, the electronic structures of these clusters and their chemical reactivity with water have been investigated...
February 17, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28211935/the-vertical-location-of-%C3%AE-tocopherol-in-phosphatidylcholine-membranes-is-not-altered-as-a-function-of-the-degree-of-unsaturation-of-the-fatty-acyl-chains
#20
Alessio Ausili, Ana M de Godos, Alejandro Torrecillas, Francisco J Aranda, Senena Corbalán-García, Juan C Gómez-Fernández
α-Tocopherol is a natural preservative that prevents free radical chain oxidations in biomembranes. We have studied the location of α-tocopherol in model membranes formed by different unsaturated phosphatidylcholines, namely 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine (PLPC), 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (PAPC) and 1-palmitoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (PDPC). Small angle X-ray diffraction revealed that α-tocopherol was well mixed with all the phospholipids...
February 17, 2017: Physical Chemistry Chemical Physics: PCCP
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