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https://www.readbyqxmd.com/read/28549332/synthesis-and-characterization-of-fullerene-modified-znalti-ldo-in-photo-degradation-of-bisphenol-a-under-simulated-visible-light-irradiation
#1
Liting Ju, Pingxiao Wu, Xiaolin Lai, Shanshan Yang, Beini Gong, Meiqing Chen, Nengwu Zhu
In this study, ZnAlTi layered double hydroxide (ZnAlTi-LDH) combined with fullerene (C60) was fabricated by the urea method, and calcined under vacuum atmosphere to obtain nanocomposites of C60-modified ZnAlTi layered double oxide (ZnAlTi-LDO). The morphology, structure and composition of the nanocomposites were analyzed by Scanning Electron Microscopy, High-resolution transmission electron microscopy, X-ray diffraction patterns, Fourier transform infrared and specific surface area. The UV-vis diffuse reflectance spectra indicated that the incorporation of C60 expanded the absorption of ZnAlTi-LDO to visible-light region...
May 23, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28549242/identification-of-related-substances-in-tofacitinib-citrate-by-lc-ms-techniques-for-synthetic-process-optimization
#2
Xiao Wu, Xuefang Zeng, Lei Wang, Taijun Hang, Min Song
A specific LC-MS method was developed for separation, identification and characterization of the process-related substances and degradation products in tofacitinib citrate. The separation was achieved on a LiChrospher C18 column (250mm×4.6mm, 5μm) by linear gradient elution of 0.1% ammonium acetate solution (pH adjusted to 4.0 by formic acid) and acetonitrile at a flow rate of 1.0mL/min. Forced degradation studies were conducted under hydrolytic (acidic, basic), oxidative, photolytic and thermal stress conditions as described in ICH...
May 13, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28549184/coiled-coil-interactions-mediate-serine-integrase-directionality
#3
Kushol Gupta, Robert Sharp, Jimmy B Yuan, Huiguang Li, Gregory D Van Duyne
Serine integrases are bacteriophage enzymes that carry out site-specific integration and excision of their viral genomes. The integration reaction is highly directional; recombination between the phage attachment site attP and the host attachment site attB to form the hybrid sites attL and attR is essentially irreversible. In a recent model, extended coiled-coil (CC) domains in the integrase subunits are proposed to interact in a way that favors the attPxattB reaction but inhibits the attLxattR reaction. Here, we show for the Listeria innocua integrase (LI Int) system that the CC domain promotes self-interaction in isolated Int and when Int is bound to attachment sites...
May 26, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28549111/diabetic-db-db-mice-do-not-develop-heart-failure-upon-pressure-overload-a-longitudinal-in-vivo-pet-mri-and-mrs-study-on-cardiac-metabolic-structural-and-functional-adaptations
#4
Desiree Abdurrachim, Miranda Nabben, Verena Hoerr, Michael T Kuhlmann, Philipp Bovenkamp, Jolita Ciapaite, Ilvy M E Geraets, Will Coumans, Joost J F P Luiken, Jan F C Glatz, Michael Schäfers, Klaas Nicolay, Cornelius Faber, Sven Hermann, Jeanine J Prompers
Aim: Heart failure is associated with altered myocardial substrate metabolism and impaired cardiac energetics. Comorbidities like diabetes may influence the metabolic adaptations during heart failure development. We quantified to what extent changes in substrate preference, lipid accumulation, and energy status predict the longitudinal development of hypertrophy and failure in the non-diabetic and the diabetic heart. Methods and results: Transverse aortic constriction (TAC) was performed in non-diabetic ( db /+) and diabetic ( db/db ) mice to induce pressure overload...
May 26, 2017: Cardiovascular Research
https://www.readbyqxmd.com/read/28548989/imaging-adult-patients-with-fontan-circulation
#5
Salil Ginde, Benjamin H Goot, Peter C Frommelt
PURPOSE OF REVIEW: Survival after the Fontan procedure for palliation of single ventricle congenital heart disease has improved. However, adults with Fontan circulation are at risk for several complications including heart failure, thromboembolism, and protein-losing enteropathy. This review discusses the role of noninvasive imaging for surveillance and early detection of anatomic and functional abnormalities of the Fontan circulation that can impact the risk for Fontan failure over time...
May 25, 2017: Current Opinion in Cardiology
https://www.readbyqxmd.com/read/28548839/structural-distortions-and-charge-density-waves-in-iodine-chains-encapsulated-inside-carbon-nanotubes
#6
Hannu-Pekka Komsa, Ryosuke Senga, Kazutomo Suenaga, Arkady V Krasheninnikov
Atomic chains are perfect systems for getting fundamental insights into the electron dynamics and coupling between the electronic and ionic degrees of freedom in one dimensional metals. Depending on the band filling, they can exhibit Peierls instabilities (or charge density waves), where equally spaced chain of atoms with partially filled band is inherently unstable, exhibiting spontaneous distortion of the lattice that further leads to metal-insulator transition in the system. Here, using high-resolution scanning transmission electron microscopy, we directly image the atomic structures of a chain of iodine atoms confined inside carbon nanotubes...
May 26, 2017: Nano Letters
https://www.readbyqxmd.com/read/28548638/asymmetric-recognition-of-hiv-1-envelope-trimer-by-v1v2-loop-targeting-antibodies
#7
Haoqing Wang, Harry B Gristick, Louise Scharf, Anthony P West, Rachel P Galimidi, Michael S Seaman, Natalia T Freund, Michel C Nussenzweig, Pamela J Bjorkman
The HIV-1 envelope (Env) glycoprotein binds to host cell receptors to mediate membrane fusion. The prefusion Env trimer is stabilized by V1V2 loops that interact at the trimer apex. Broadly neutralizing antibodies (bNAbs) against V1V2 loops, exemplified by PG9, bind asymmetrically as a single Fab to the apex of the symmetric Env trimer using a protruding CDRH3 to penetrate the Env glycan shield. Here we characterized a distinct mode of V1V2 epitope recognition by the new bNAb BG1 in which two Fabs bind asymmetrically per Env trimer using a compact CDRH3...
May 26, 2017: ELife
https://www.readbyqxmd.com/read/28548163/crystal-structure-of-aquifex-aeolicus-gene-product-aq1627-a-putative-phosphoglucosamine-mutase-reveals-a-unique-c-terminal-end-to-end-disulfide-linkage
#8
Upasana Sridharan, Seiki Kuramitsu, Shigeyuki Yokoyama, Thirumananseri Kumarevel, Karthe Ponnuraj
The Aq1627 gene from Aquifex aeolicus, a hyperthermophilic bacterium has been cloned and overexpressed in Escherichia coli. The protein was purified to homogeneity and its X-ray crystal structure was determined to 1.3 Å resolution using multiple wavelength anomalous dispersion phasing. The structural and sequence analysis of Aq1627 is suggestive of a putative phosphoglucosamine mutase. The structural features of Aq1627 further indicate that it could belong to a new subclass of the phosphoglucosamine mutase family...
May 26, 2017: Molecular BioSystems
https://www.readbyqxmd.com/read/28548083/atomic-scale-age-resolution-of-planetary-events
#9
L F White, J R Darling, D E Moser, D A Reinhard, T J Prosa, D Bullen, D Olson, D J Larson, D Lawrence, I Martin
Resolving the timing of crustal processes and meteorite impact events is central to understanding the formation, evolution and habitability of planetary bodies. However, identifying multi-stage events from complex planetary materials is highly challenging at the length scales of current isotopic techniques. Here we show that accurate U-Pb isotopic analysis of nanoscale domains of baddeleyite can be achieved by atom probe tomography. Within individual crystals of highly shocked baddeleyite from the Sudbury impact structure, three discrete nanostructural domains have been isolated yielding average (206)Pb/(238)U ages of 2,436±94 Ma (protolith crystallization) from homogenous-Fe domains, 1,852±45 Ma (impact) from clustered-Fe domains and 1,412±56 Ma (tectonic metamorphism) from planar and subgrain boundary structures...
May 26, 2017: Nature Communications
https://www.readbyqxmd.com/read/28547827/digital-dissection-of-the-model-organism-xenopus-laevis-using-contrast-enhanced-computed-tomography
#10
Laura B Porro, Christopher T Richards
The African clawed frog, Xenopus laevis, is one of the most widely used model organisms in biological research. However, the most recent anatomical description of X. laevis was produced nearly a century ago. Compared with other anurans, pipid frogs - including X. laevis - exhibit numerous unusual morphological features; thus, anatomical descriptions of more 'typical' frogs do not detail many aspects of X. laevis skeletal and soft-tissue morphology. The relatively new method of using iodine-based agents to stain soft tissues prior to high-resolution X-ray imaging has several advantages over gross dissection, such as enabling dissection of very small and fragile specimens, and preserving the three-dimensional topology of anatomical structures...
May 26, 2017: Journal of Anatomy
https://www.readbyqxmd.com/read/28547317/pelvic-pain-in-the-middle-of-the-night-use-of-mri-for-evaluation-of-pediatric-female-pathology-in-the-emergent-setting
#11
Rama S Ayyala, Asef Khwaja, Sudha A Anupindi
Acute pelvic pain in pediatric female patients is a common cause of emergency room visits. Imaging plays a crucial role in the clinical evaluation of these patients. Pelvic pain in female children can result from various pathologies. Ultrasound is the preferred first line imaging study; however, magnetic resonance imaging (MRI) is a helpful adjunct after hours, as it is available 24/7 in many institutions. Advantages of MRI include superior delineation of anatomy and higher tissue contrast resolution, particularly of the small pelvic structures...
May 25, 2017: Emergency Radiology
https://www.readbyqxmd.com/read/28547116/groove-binding-of-vanillin-and-ethyl-vanillin-to-calf-thymus-dna
#12
Kaixin Xia, Guowen Zhang, Song Li, Deming Gong
Vanillin (VAN) and ethyl vanillin (EVA) are widely used food additives as flavor enhancers, but may have a potential security risk. In this study, the properties of binding of VAN or EVA with calf thymus DNA (ctDNA) were characterized by multi-spectroscopic methods, multivariate curve resolution-alternating least-squares (MCR-ALS) algorithm and molecular simulation. The concentration profiles for the components (VAN or EVA, ctDNA and VAN-ctDNA or EVA-ctDNA complex) by the MCR-ALS analysis showed that VAN or EVA interacted with ctDNA and formed VAN-ctDNA or EVA-ctDNA complex...
May 25, 2017: Journal of Fluorescence
https://www.readbyqxmd.com/read/28546533/comparison-of-accuracy-between-fsl-s-first-and-freesurfer-for-caudate-nucleus-and-putamen-segmentation
#13
Gabor Perlaki, Reka Horvath, Szilvia Anett Nagy, Peter Bogner, Tamas Doczi, Jozsef Janszky, Gergely Orsi
Although several methods have been developed to automatically delineate subcortical gray matter structures from MR images, the accuracy of these algorithms has not been comprehensively examined. Most of earlier studies focused primarily on the hippocampus. Here, we assessed the accuracy of two widely used non-commercial programs (FSL-FIRST and Freesurfer) for segmenting the caudate and putamen. T1-weighted 1 mm(3) isotropic resolution MR images were acquired for thirty healthy subjects (15 females). Caudate nucleus and putamen were segmented manually by two independent observers and automatically by FIRST and Freesurfer (v4...
May 25, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28546025/molecular-and-functional-characterization-of-a-glycosylated-galactose-binding-lectin-from-mytilus-californianus
#14
Efrén García-Maldonado, Patricia Cano-Sánchez, Alejandra Hernández-Santoyo
Lectins play crucial roles for innate immune responses in invertebrates by recognizing and eliminating pathogens. In this study, a lectin from the mussel Mytilus californianus (MCL) was identified and characterized. The lectin was purified by affinity chromatography in α-lactose-agarose resin showing an experimental molecular weight of 18000 Da as determined by SDS-PAGE and MALDI-TOF mass spectrometry. It was specific for binding d-galactose and N-Acetyl-d-galactosamine that contained carbohydrate moieties that were also inhibited by melibiose and raffinose...
May 22, 2017: Fish & Shellfish Immunology
https://www.readbyqxmd.com/read/28545305/clostridium-difficile-toxins-a-and-b-receptors-pores-and-translocation-into-cells
#15
Kathleen E Orrell, Zhifen Zhang, Seiji N Sugiman-Marangos, Roman A Melnyk
The most potent toxins secreted by pathogenic bacteria contain enzymatic moieties that must reach the cytosol of target cells to exert their full toxicity. Toxins such as anthrax, diphtheria, and botulinum toxin all use three well-defined functional domains to intoxicate cells: a receptor-binding moiety that triggers endocytosis into acidified vesicles by binding to a specific host-cell receptor, a translocation domain that forms pores across the endosomal membrane in response to acidic pH, and an enzyme that translocates through these pores to catalytically inactivate an essential host cytosolic substrate...
May 26, 2017: Critical Reviews in Biochemistry and Molecular Biology
https://www.readbyqxmd.com/read/28544744/structural-basis-for-copper-oxygen-mediated-c-h-bond-activation-by-the-formylglycine-generating-enzyme
#16
Marcel Meury, Matthias Knop, Florian P Seebeck
The formylglycine-generating enzyme (FGE) is a unique copper-protein that catalyzes oxygen-dependent C-H activation. We describe 1.66 Å- and 1.28 Å-resolution crystal structures of FGE from Thermomonospora curvata in complex with either Ag (I) or Cd (II) providing definitive evidence for a high-affinity metal-binding site in this enzyme. The structures reveal a bis-cysteine linear coordination of the monovalent metal, and tetrahedral coordination of the bivalent metal. Similar coordinational change may occur in the active enzyme as a result of Cu (I)/(II) redox cycling...
May 22, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28544670/the-clinical-significance-of-esophagogastric-junction-outflow-obstruction-and-hypercontractile-esophagus-in-high-resolution-esophageal-manometry
#17
D Schupack, D A Katzka, D M Geno, K Ravi
BACKGROUND: Although major manometric abnormalities, the significance of esophagogastric junction outflow obstruction (EGJOO) and hypercontractile esophagus (HE) is poorly understood. We sought to determine long term outcomes for EGJOO and HE. METHODS: High-resolution impedance manometry (HRIM) studies conducted from 5/30/2012 to 8/1/2014 consistent with EGJOO and HE and normal studies from 5/30/12 to 11/1/12 were identified. Standardized follow up was conducted with a phone survey utilizing the impact dysphagia questionnaire (IDQ-10)...
May 23, 2017: Neurogastroenterology and Motility: the Official Journal of the European Gastrointestinal Motility Society
https://www.readbyqxmd.com/read/28544582/evaluation-by-medical-students-of-the-educational-value-of-multi-material-and-multi-colored-three-dimensional-printed-models-of-the-upper-limb-for-anatomical-education
#18
Sreenivasulu Reddy Mogali, Wai Yee Yeong, Heang Kuan Joel Tan, Gerald Jit Shen Tan, Peter H Abrahams, Nabil Zary, Naomi Low-Beer, Michael Alan Ferenczi
For centuries, cadaveric material has been the cornerstone of anatomical education. For reasons of changes in curriculum emphasis, cost, availability, expertise, and ethical concerns, several medical schools have replaced wet cadaveric specimens with plastinated prosections, plastic models, imaging, and digital models. Discussions about the qualities and limitations of these alternative teaching resources are on-going. We hypothesize that three-dimensional printed (3DP) models can replace or indeed enhance existing resources for anatomical education...
May 19, 2017: Anatomical Sciences Education
https://www.readbyqxmd.com/read/28544388/healing-effect-of-controlled-anti-electromigration-on-conventional-and-high-tc-superconducting-nanowires
#19
Xavier D A Baumans, Joseph Lombardo, Jérémy Brisbois, Gorky Shaw, Vyacheslav S Zharinov, Ge He, Heshan Yu, Jie Yuan, Beiyi Zhu, Kui Jin, Roman B G Kramer, Joris Van de Vondel, Alejandro V Silhanek
The electromigration process has the potential capability to move atoms one by one when properly controlled. It is therefore an appealing tool to tune the cross section of monoatomic compounds with ultimate resolution or, in the case of polyatomic compounds, to change the stoichiometry with the same atomic precision. As demonstrated here, a combination of electromigration and anti-electromigration can be used to reversibly displace atoms with a high degree of control. This enables a fine adjustment of the superconducting properties of Al weak links, whereas in Nb the diffusion of atoms leads to a more irreversible process...
May 19, 2017: Small
https://www.readbyqxmd.com/read/28544357/classification-of-esophageal-motor-findings-in-gastro-esophageal-reflux-disease-conclusions-from-an-international-consensus-group
#20
REVIEW
C P Gyawali, S Roman, A J Bredenoord, M Fox, J Keller, J E Pandolfino, D Sifrim, R Tatum, R Yadlapati, E Savarino
BACKGROUND: High-resolution manometry (HRM) has resulted in new revelations regarding the pathophysiology of gastro-esophageal reflux disease (GERD). The impact of new HRM motor paradigms on reflux burden needs further definition, leading to a modern approach to motor testing in GERD. METHODS: Focused literature searches were conducted, evaluating pathophysiology of GERD with emphasis on HRM. The results were discussed with an international group of experts to develop a consensus on the role of HRM in GERD...
May 24, 2017: Neurogastroenterology and Motility: the Official Journal of the European Gastrointestinal Motility Society
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