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https://www.readbyqxmd.com/read/28102932/antileukemic-action-of-novel-diamine-pt-ii-halogenido-complexes-comparison-of-the-representative-novel-pt-ii-with-corresponding-pt-iv-complex
#1
Sonja Misirlić Denčić, Jelena Poljarević, Andjelka M Isakovic, Ivanka Marković, Tibor J Sabo, Sanja Grgurić-Šipka
This study presents the synthesis, characterization and antitumor action of five new Pt(II) halogenido, chlorido and iodido, complexes with edda type of ligands. (S,S)-ethylendiamine-N,N'-di-2-(3-cyclohexyl)propanoic acid dihydrochloride and its methyl, ethyl and n-propyl esters, were prepared according to the previously reported procedure. All investigated complexes were characterized by IR, ESI-MS, ((1) H, (13) C and HMBC) NMR spectroscopy and elemental analysis. Their cytotoxic action was investigated in four human tumor cell lines: promyelocytic (HL-60) and lymphocytic (REH) leukemia, glioma (U251) and lung carcinoma (H460)...
January 19, 2017: Chemical Biology & Drug Design
https://www.readbyqxmd.com/read/28102914/nano-koosh-balls-of-mesoporous-mno2-improved-supercapacitor-performance-through-superior-ion-transport
#2
Aasheesh Srivastava, Qysar Maqbool, Chanderpratap Singh, Priyajit Jash, Amit Paul
Manganese dioxide nanomaterials with "Koosh-ball" like morphology (MnO2-KBs) as well as worm-like nanotubes (MnO2-NWs) were obtained by employing Tween 20 as the reducing-cum-structure-directing agent, and KMnO4 as a MnO2 precursor. While the MnO2-KBs were interconnected with each other through tubular extensions, MnO2-NWs were largely disconnected. Both MnO2-KBs and MnO2-NWs had large BET surface areas (>200 m2/g), and were thermally robust upto 300 ⁰C. The electrochemical studies revealed that the highest specific capacitance (Csp) obtained for MnO2-KBs was significantly higher (272 F/g) than that of MnO2-NWs (129 F/g)...
January 19, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28102856/the-impact-of-integrated-evaluation-of-hemodynamics-using-targeted-neonatal-echocardiography-with-indices-of-tissue-oxygenation-a-new-approach
#3
Y N Elsayed, R Amer, M M Seshia
OBJECTIVE: To study the impact of integrated evaluation of hemodynamics (IEH) using targeted neonatal echocardiography, together with regional tissue oxygenation, fractional oxygen extraction using near-infrared spectroscopy on the management of infants with compromised hemodynamics. STUDY DESIGN: Retrospective cohort comparison of two groups of infants with compromised hemodynamics. EPOCH 1: did not undergo IEH (January 2012 to March 2014); EPOCH 2: underwent IEH (April 2014 to December 2015)...
January 19, 2017: Journal of Perinatology: Official Journal of the California Perinatal Association
https://www.readbyqxmd.com/read/28102738/optimization-and-partial-characterization-of-intracellular-anticandidal-protein-from-aspergillus-giganteus-mtcc-8408-using-taguchi-doe
#4
Debashis Dutta, Mira Debnath Das
A new intracellular antifungal protein (afp) production with average molecular weight 24.3 kDa and yield of 0.65 ± 0.1 mg/gram dry cell weight (gdcw) of mycelia in submerged fermentation of Aspergillus giganteus MTCC 8408 was optimized. Taguchi's DOE (design of experiment) L27 orthogonal array (OA) was constructed using Qualitek-4 software with 8 most influensive factors namely, culture pH, temperature, slant age, inoculum volume, agitation and KH2PO4. Scanning electron microscopy (SEM) was used to correlate the effect of selected factors on fungal cell morphology and afp production...
January 19, 2017: Bioengineered
https://www.readbyqxmd.com/read/28102685/direct-assignment-of-the-threo-and-erythro-configurations-in-polyacetylene-glycosides-by-1-h-nmr-spectroscopy
#5
Kuo Xu, Peng-Fei Yang, Ya-Nan Yang, Zi-Ming Feng, Jian-Shuang Jiang, Pei-Cheng Zhang
An approach for discriminating the threo and erythro configurations of polyacetylene glycosides by (1)H NMR spectroscopy was developed. Using acetic acid-d4/D2O as the solvent, a relatively larger (3)JHH value (7.0 Hz) for the acyclic vicinal diol group was unambiguously assigned to the threo configuration, whereas the smaller value (3.5 Hz) was assigned to the erythro configuration. This convenient method requires no hydrolysis or derivatization and is suitable for micromolar concentrations of polyacetylene glycosides...
January 19, 2017: Organic Letters
https://www.readbyqxmd.com/read/28102680/ionicity-of-protic-ionic-liquid-quantitative-measurement-by-spectroscopic-methods
#6
Minming Shen, Yuyang Zhang, Kaizhou Chen, Siying Che, Jia Yao, Haoran Li
The ionicity value, which is a key property of protic ionic liquids, was obtained by the attenuated total reflection Fourier transform infrared spectroscopy and nuclear magnetic resonance respectively for a protic ionic liquid: n-propylammonium acetate. The method of potentiometric titration is found not suitable for such kind of ionic liquid as the ∆pKa of the compositing acid and base is relatively small. In the IR spectrum, molecular species can be directly observed in the range 1200-1800 cm-1, and the ratio of ionic and molecular species can be quantitatively calculated by the area of characteristic absorption peaks calibrated by standard curve from NaAc/HAc solutions...
January 19, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28102675/mechanistic-elucidation-of-zirconium-catalyzed-direct-amidation
#7
Helena Lundberg, Fredrik Tinnis, Jiji Zhang, Andrés G Algarra, Fahmi Himo, Hans Adolfsson
The mechanism of the zirconium-catalyzed condensation of carboxylic acids and amines for direct formation of amides was studied using kinetics, NMR-spectroscopy and DFT-calculations. The reaction is found to be first order with respect to catalyst and has a positive rate dependence on amine concentration and a negative rate dependence on carboxylic acid concentration. Kinetic experiments using Reaction Progress Kinetic Analysis (RPKA) protocols demonstrate that inhibition of the catalyst by the amide product can be avoided using a high amine concentration...
January 19, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28102674/2d-ir-spectroscopy-shows-that-optimised-dna-minor-groove-binding-of-hoechst33258-follows-an-induced-fit-model
#8
Lennart A I Ramakers, Gordon Hithell, John J May, Gregory M Greetham, Paul M Donaldson, Michael Towrie, Anthony W Parker, Glenn A Burley, Neil T Hunt
The induced fit binding model describes a conformational change occurring when a small molecule binds to its biomacromolecular target. The result is enhanced non-covalent interactions between ligand and biomolecule. Induced fit is well-established for small molecule-protein interactions, but its relevance to small molecule-DNA binding is less clear. We investigate the molecular determinants of Hoechst33258 binding to its preferred A-tract sequence relative to a sub-optimal alternating A-T sequence. Results from 2-dimensional infrared spectroscopy, which is sensitive to H-bonding and molecular structure changes, show that Hoechst33258 binding results in loss of minor groove spine of hydration in both sequences, but an additional perturbation of the base propeller twists occurs in the A-tract binding region...
January 19, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28102665/cosolute-and-crowding-effects-on-a-side-by-side-protein-dimer
#9
Alex J Guseman, Gary J Pielak
The effects of small (~102 Da) and larger (>103 Da) cosolutes on protein stability are broadly understood: excluding volume stabilizes proteins, and chemical interactions are stabilizing when repulsive, but destabilizing when attractive. Proteins, however, rarely work alone. Here, we investigate the effects of small and larger cosolutes on the equilibrium stability of the simplest defined protein-protein interactions, the side-by-side homodimer formed by the A34F variant of the 56-residue B1 domain of protein G...
January 19, 2017: Biochemistry
https://www.readbyqxmd.com/read/28102565/development-of-novel-sers-probe-for-selective-screening-of-healthy-prostate-from-malignant-prostate-cancer-cells-using-zn-ii
#10
Paresh Chandra Ray, Avijit Pramanik, Suhash Reddy Chavva, Bhanu Priya Viraka Nellore, Kelli May, Tejus Matthew, Stacy Jones, Aruna Vangara
Even in 21st century, prostate cancer remains the second leading cause of cancer death for men. Since normal prostate gland contains the most Zn(II) and there are huge differences in Zn(II) content between the healthy and malignant prostate cancer cells, mobile zinc can be used as a biomarker for prostate cancer prediction. Current article reports the design of novel and highly efficient surface enhanced Raman spectroscopy (SERS) probe using p-(imidazole)azo) benzenethiol attached gold nanoparticle as a Raman reporter, which has the capability to identify prostate cancer cells based on Zn(II) sensing...
January 19, 2017: Chemistry, An Asian Journal
https://www.readbyqxmd.com/read/28102402/brillouin-flow-cytometry-for-label-free-mechanical-phenotyping-of-the-nucleus
#11
Jitao Zhang, Xuefei A Nou, Hanyoup Kim, Giuliano Scarcelli
The mechanical properties of the nucleus are closely related to many cellular functions; thus, measuring nuclear mechanical properties is crucial to our understanding of cell biomechanics and could lead to intrinsic biophysical contrast mechanisms to classify cells. Although many technologies have been developed to characterize cell stiffness, they generally require contact with the cell and thus cannot provide direct information on nuclear mechanical properties. In this work, we developed a flow cytometry technique based on an all-optical measurement to measure nuclear mechanical properties by integrating Brillouin spectroscopy with microfluidics...
January 19, 2017: Lab on a Chip
https://www.readbyqxmd.com/read/28102389/the-decomposition-of-benzenesulfonyl-azide-a-matrix-isolation-and-computational-study
#12
Guohai Deng, Xuelin Dong, Qifan Liu, Dingqing Li, Hongmin Li, Qiao Sun, Xiaoqing Zeng
The thermal-decomposition and photo-decomposition of benzenesulfonyl azide, PhS(O)2N3, have been studied by combining matrix-isolation IR spectroscopy and quantum chemical calculations. Upon flash vacuum pyrolysis at 800 K, the azide splits off molecular nitrogen and exclusively furnishes phenylnitrene (PhN) and SO2 in the gas phase. In contrast, the azide favors stepwise photodecomposition in solid Ar and Ne matrices at 2.8 K. Specifically, the UV laser photolysis (193 and 266 nm) of PhS(O)2N3 results in the formation of the key nitrene intermediate PhS(O)2N in the triplet ground state, which undergoes pseudo-Curtius rearrangement into N-sulfonyl imine PhNSO2 under subsequent visible light irradiation (380-450 nm)...
January 19, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28102388/crystal-structure-of-ba2-la0-727ba0-182m0-091-mo6-m-nb-sb-bi-symmetry-nuance-identified-in-photoluminescence-and-ir-spectroscopy-studies
#13
Rohan Phatak, Santosh K Gupta, Priya Maheshwari, Amitabh Das, Sanjay K Sali
A one-third lanthanum deficiency was created in Ba2LaM(5+)O6 compounds (LaM compounds) to form Ba2La2/3M(5+)O5.5 compounds (La2/3M compounds) for M = Nb, Sb, and Bi. The compounds were prepared by a gel-combustion method using citric acid as a fuel. All the compounds were characterized by powder X-ray diffraction (XRD). The XRD analysis showed that the space group of the La2/3M compounds remains the same for the Bi and Sb samples when compared to the reported LaM compounds, except for the Nb sample. La2/3Nb and La2/3Sb adopt a rhombohedral structure with the space group R3[combining macron], whereas La2/3Bi adopts a monoclinic structure with the space group I2/m...
January 19, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28102372/structure-transport-and-photoconductance-of-pbs-quantum-dot-monolayers-functionalized-with-a-copper-phthalocyanine-derivative
#14
A André, C Theurer, J Lauth, S Maiti, M Hodas, M Samadi Khoshkhoo, S Kinge, A J Meixner, F Schreiber, L D A Siebbeles, K Braun, M Scheele
We simultaneously surface-functionalize PbS nanocrystals with Cu 4,4',4'',4'''-tetraaminophthalocyanine and assemble this hybrid material into macroscopic monolayers. Electron microscopy and X-ray scattering reveal a granular mesocrystalline structure with strong coherence between the atomic lattice and the superlattice of nanocrystals within each domain. Terahertz spectroscopy and field-effect transistor measurements indicate efficient coupling of holes throughout the hybrid thin film, in conjunction with a pronounced photoresponse...
January 19, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28102368/novel-electron-phonon-relaxation-pathway-in-graphite-revealed-by-time-resolved-raman-scattering-and-angle-resolved-photoemission-spectroscopy
#15
Jhih-An Yang, Stephen Parham, Daniel Dessau, Dmitry Reznik
Time dynamics of photoexcited electron-hole pairs is important for a number of technologies, in particular solar cells. We combined ultrafast pump-probe Raman scattering and photoemission to directly follow electron-hole excitations as well as the G-phonon in graphite after an excitation by an intense laser pulse. This phonon is known to couple relatively strongly to electrons. Cross-correlating effective electronic and phonon temperatures places new constraints on model-based fits. The accepted two-temperature model predicts that G-phonon population should start to increase as soon as excited electron-hole pairs are created and that the rate of increase should not depend strongly on the pump fluence...
January 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28102335/erratum-measuring-the-complex-optical-conductivity-of-graphene-by-fabry-p%C3%A3-rot-reflectance-spectroscopy
#16
Behnood G Ghamsari, Jacob Tosado, Mahito Yamamoto, Michael S Fuhrer, Steven M Anlage
No abstract text is available yet for this article.
January 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28102320/polarization-conversion-in-plasmonic-nanoantennas-for-metasurfaces-using-structural-asymmetry-and-mode-hybridization
#17
Peter R Wiecha, Leo-Jay Black, Yudong Wang, Vincent Paillard, Christian Girard, Otto L Muskens, Arnaud Arbouet
Polarization control using single plasmonic nanoantennas is of interest for subwavelength optical components in nano-optical circuits and metasurfaces. Here, we investigate the role of two mechanisms for polarization conversion by plasmonic antennas: Structural asymmetry and plasmon hybridization through strong coupling. As a model system we investigate L-shaped antennas consisting of two orthogonal nanorods which lengths and coupling strength can be independently controlled. An analytical model based on field susceptibilities is developed to extract key parameters and to address the influence of antenna morphology and excitation wavelength on polarization conversion efficiency and scattering intensities...
January 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28102317/time-resolved-neutron-scattering-provides-new-insight-into-protein-substrate-processing-by-a-aaa-unfoldase
#18
Ziad Ibrahim, Anne Martel, Martine Moulin, Henry S Kim, Michael Härtlein, Bruno Franzetti, Frank Gabel
We present a combination of small-angle neutron scattering, deuterium labelling and contrast variation, temperature activation and fluorescence spectroscopy as a novel approach to obtain time-resolved, structural data individually from macromolecular complexes and their substrates during active biochemical reactions. The approach allowed us to monitor the mechanical unfolding of a green fluorescent protein model substrate by the archaeal AAA+ PAN unfoldase on the sub-minute time scale. Concomitant with the unfolding of its substrate, the PAN complex underwent an energy-dependent transition from a relaxed to a contracted conformation, followed by a slower expansion to its initial state at the end of the reaction...
January 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28102312/correlations-of-charge-neutrality-level-with-electronic-structure-and-p-d-hybridization
#19
Arkaprava Das, Subodh K Gautam, D K Shukla, Fouran Singh
The formation of charge neutrality level (CNL) in highly conducting Cadmium oxide (CdO) thin films is demonstarted by the observed variation in the band gap upon annealing and doping. It may be explained by the observation that Tin (Sn) doping breaks the perfect periodicity of CdO cubic crystal structure and creates virtual gap states (ViGS). The level of local CNL resides at the branch point of ViGS, making the energy at which native defect's character changes from predominantly donor-like below CNL to predominantly acceptor-like above the CNL and a schematic band diagram is developed to substantiate the same...
January 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28102296/surface-reconstructions-and-related-local-properties-of-a-bifeo3-thin-film
#20
L Jin, P X Xu, Y Zeng, L Lu, J Barthel, T Schulthess, R E Dunin-Borkowski, H Wang, C L Jia
Coupling between lattice and order parameters, such as polarization in ferroelectrics and/or polarity in polar structures, has a strong impact on surface relaxation and reconstruction. However, up to now, surface structures that involve the termination of both matrix polarization and polar atomic planes have received little attention, particularly on the atomic scale. Here, we study surface structures on a BiFeO3 thin film using atomic-resolution scanning transmission electron microscopy and spectroscopy. Two types of surface structure are found, depending on the polarization of the underlying ferroelectric domain...
January 19, 2017: Scientific Reports
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