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Xianzhi Meng, YUnqiao Pu, Chang Geun Yoo, Mi Li, Garima Bali, Doh-Yeon Park, Erica Gjersing, Mark Davis, Muchero Wellington, Gerald Tuskan, Timothy Tschaplinski, Arthur Jonas Ragauskas
In an effort to better understand and overcome biomass recalcitrance, six natural poplar variants were selected as the feedstock. Compositional analysis and physicochemical characterizations of these poplars were performed using different analytical techniques and the correlations between these physicochemical properties and enzymatic hydrolysis yield were investigated. Gel permeation chromatography (GPC) and 13C NMR were used to determine the degree of polymerization (DP) and crystallinity index (CrI) of cellulose, and the results along with the sugar release study indicated that cellulose DP likely played a more important role in enzymatic hydrolysis...
November 23, 2016: ChemSusChem
Pierre G Carlier, Benjamin Marty, Olivier Scheidegger, Paulo Loureiro de Sousa, Pierre-Yves Baudin, Eduard Snezhko, Dmitry Vlodavets
Recent years have seen tremendous progress towards therapy of many previously incurable neuromuscular diseases. This new context has acted as a driving force for the development of novel non-invasive outcome measures. These can be organized in three main categories: functional tools, fluid biomarkers and imagery. In the latest category, nuclear magnetic resonance imaging (NMRI) offers a considerable range of possibilities for the characterization of skeletal muscle composition, function and metabolism. Nowadays, three NMR outcome measures are frequently integrated in clinical research protocols...
March 3, 2016: Journal of Neuromuscular Diseases
Mario L Naitana, Sara Nardis, Giuseppe Pomarico, Michele Raggio, Fabrizio Caroleo, Daniel O Cicero, Sara Lentini, Luca Prodi, Damiano Genovese, Saisameera Mitta, Anna Sgarlata, Massimo Fanfoni, Luca Persichetti, Roberto Paolesse
The synthesis, spectroscopic, and optical properties of the water-soluble phosphorus complex of a 2-sulfonato-10-(4-sulfonatophenyl)-5,15-dimesitylcorrole have been investigated. The compound was prepared by adopting a novel strategy for the corrole sulfonation, leading to the regioselective isomer in an almost quantitative yield. The phosphorus coordination has a key role in determining the corrole substitution pattern, limiting the formation of poly-substituted species, which affected the reaction of the corrole free base...
October 27, 2016: Chemistry: a European Journal
Elisa Fabbri, Chee W Chia, Richard G Spencer, Kenneth W Fishbein, David A Reiter, Donnie Cameron, Ariel C Zane, Zenobia A Moore, Marta Gonzalez-Freire, Marco Zoli, Stephanie A Studenski, Rita R Kalyani, Josephine M Egan, Luigi Ferrucci
Whether individuals with insulin resistance but without criteria for diabetes exhibit reduced mitochondrial oxidative capacity is unclear; addressing this question could guide research for new therapeutics. We investigated 248 non-diabetic participants from the Baltimore Longitudinal Study of Aging (BLSA) to determine whether impaired mitochondrial capacity is associated with prediabetes, insulin resistance, duration and severity of hyperglycemia exposure. Mitochondrial capacity was assessed as post-exercise phosphocreatine recovery time constant (τPCr) by (31)P-magnetic resonance spectroscopy, with higher τPCr reflecting reduced capacity...
October 13, 2016: Diabetes
William Lorne McClennan, Stephanie Alyssa Rufh, Justin Alexander MacDonald Lummiss, Deryn Elizabeth Fogg
Sterically accessible Lewis donors are shown to accelerate decomposition during catalysis, for a broad range of Grubbs-class metathesis catalysts. These include benzylidene derivatives RuCl2(NHC)(PCy3)(=CHPh) (Ru-2: NHC = H2IMes, a; IMes, b; H2IPr, c; IPr, d; H2ITol, e) and indenylidene complexes RuCl2(NHC)(PCy3)(=C15H10) (NHC = H2IMes, Ru-2f; IMes, Ru-2g). All of these precatalysts form methylidene complex RuCl2(NHC)(=CH2) Ru-3 as the active species in metathesis of terminal olefins, and generate RuCl2(NHC)(PCy3)(=CH2) Ru-4 as the catalyst resting state...
October 13, 2016: Journal of the American Chemical Society
Hannah Dengel, Crispin Lichtenberg
The synthetic access to cationic bismuth compounds based on simple, monodentate, synthetically useful amido ligands, [Bi(NR2 )2 (L)n ](+) , has been investigated (R=Me, iPr, Ph; L=neutral ligand). With [BPh4 ](-) as a counteranion, the formation of contact ion pairs and subsequent phenyl transfer from B to Bi is observed. An intermediate of this reaction, [Bi(NMe2 )2 (HNMe2 )(BPh4 )] (1), could be isolated and fully characterized. The use of a fluorinated tetraarylborate as a counteranion leads to more stable cationic bismuth amides...
October 12, 2016: Chemistry: a European Journal
Fernando López Ortiz, Jesús García López, Maria Casimiro, María José Iglesias
The structure of the dianion (SP,RC)-10 formed in the diastereoselective N,Cortho dilithiation of the phosphinimidic amide (RC)-Ph2P(=NCO2Me)NHCH(Me)Ph 5 (dr of 95:5) with tert-butyllithium in THF has been elucidated using multinuclear magnetic resonance methods including 2D 7Li,nX-HMQC (nX = 15N, 31P) correlations. (SP,RC)-10 consists of a monomer in which C,N and N,O chelation of the lithium cations generate a system containing a five- and a six-membered metallacycle, respectively, sharing a P-N bond and with the lithium atoms connected through the NCO moiety of the phosphazenyl group...
October 7, 2016: Journal of Organic Chemistry
Juho Roukala, Simon Orr, John V Hanna, Juha Vaara, Alexander V Ivanov, Oleg N Antzutkin, Perttu Lantto
Polycrystalline bis(dialkyldithiophosphato)Pt(II) complexes of the form Pt{S2P(OR)2}2 (R = ethyl, iso-propyl, iso-butyl, sec-butyl or cyclo-hexyl group) were studied using solid-state 31P and 195Pt NMR spectroscopy to determine the influence of the alkyl substituents to the structure of the central chromophore. Measured anisotropic chemical shift (CS) parameters for 31P and 195Pt tensors afford more detailed chemical and structural information as compared to isotropic NMR parameters, such as chemical shifts and J-couplings, alone...
September 30, 2016: Journal of Physical Chemistry. A
Veronique Deschodt-Arsac, Laurent Arsac, Julie Magat, Jerome Naulin, Bruno Quesson, Pierre Dos Santos
INTRODUCTION: Gradual alterations in cardiac energy balance, as assessed by the myocardial PCr/ATP-ratio, are frequently associated with the development of cardiac disease. Despite great interest for the follow-up of myocardial PCr and ATP content, cardiac MR-spectroscopy in rat models in vivo is challenged by sensitivity issues and cross-contamination from other organs. METHODS: Here we combined MR-Imaging and MR-Spectroscopy (Bruker BioSpec 9.4T) to follow-up for the first time in vivo the cardiac energy balance in the SHR, a genetic rat model of cardiac hypertrophy known to develop early disturbances in cytosolic calcium dynamics...
2016: PloS One
Masha M Rosenberg, Alfred G Redfield, Mary F Roberts, Lizbeth Hedstrom
Guanosine-5'-monophosphate reductase (GMPR) catalyzes the reduction of GMP to IMP and ammonia with concomitant oxidation of NADPH. Here we investigated the structure and dynamics of enzyme-bound substrates and cofactors by measuring (31)P relaxation rates over a large magnetic field range using high resolution field cycling NMR relaxometry. Surprisingly, these experiments reveal differences in the low field relaxation profiles for the monophosphate of GMP compared with IMP in their respective NADP(+) complexes...
October 28, 2016: Journal of Biological Chemistry
Ling Gao, Weina Cui, Pengyuan Zhang, Albert Jang, Wuqiang Zhu, Jianyi Zhang
Utilizing a fast 31P magnetic resonance spectroscopy (MRS) 2-dimensional chemical shift imaging (2D-CSI) method, this study examined the heterogeneity of creatine kinase (CK) forward flux rate of hearts with postinfarction left ventricular (LV) remodeling. Immunosuppressed Yorkshire pigs were assigned to 4 groups: 1) A sham-operated normal group (SHAM, n = 6); 2) A 60 minutes distal left anterior descending coronary artery ligation and reperfusion (MI, n = 6); 3) Open patch group; ligation injury plus open fibrin patch over the site of injury (Patch, n = 6); and 4) Cell group, hiPSCs-cardiomyocytes, -endothelial cells, and -smooth muscle cells (2 million, each) were injected into the injured myocardium pass through a fibrin patch (Cell+Patch, n = 5)...
2016: PloS One
David G Harper, J Eric Jensen, Caitlin Ravichandran, Roy H Perlis, Maurizio Fava, Perry F Renshaw, Dan V Iosifescu
Brain bioenergetic abnormalities have been observed frequently in adults with major depressive disorder (MDD); however, results have been inconsistent regarding whether decreased or increased metabolism was observed. Phosphorus-31 magnetic resonance spectroscopy (31P MRS) allows for the quantification of bioenergetic molecules, containing high-energy phosphates, over the whole brain as well as measuring the differences between gray matter and white matter. We recruited 50 subjects with a current diagnosis of MDD, not currently treated with psychotropic medication, between ages of 18 and 65 (mean±SD age: 43...
October 5, 2016: Neuropsychopharmacology: Official Publication of the American College of Neuropsychopharmacology
Jian-She Zhu, Nicole E McCormick, Shannon C Timmons, David L Jakeman
Eight fluorinated isosteric α-d-glucopyranosyl 1-phosphate (Glc 1P) analogues have been synthesized. A promiscuity investigation of the thymidylyltransferase Cps2L and the guanidylyltansferase GDP-ManPP with these analogues showed that all were accepted by either enzyme, with the exception of 1,6-diphosphate 6. Kinetic parameters were determined for these analogues using a continuous coupled assay. These data demonstrated the broad substrate promiscuity of Cps2L, with kcat/Km changes for monofluoro substitution at C-2, C-4, and C-6 and difluoro substitution at C-2 within two orders of magnitude...
October 7, 2016: Journal of Organic Chemistry
Ryoichi Matsui, Noriyuki Uchida, Masataka Ohtani, Kuniyo Yamada, Arisu Shigeta, Izuru Kawamura, Takuzo Aida, Yasuhiro Ishida
Five novel surfactants were prepared by modifying the three hydroxy groups of sodium cholate with triethylene glycol chains endcapped with an amide (SC-C1 , SC-(n) C4 , and SC-(n) C5 ) or a carbamoyl group (SC-O(n) C4 and SC-O(t) C4 ). The phase behavior of aqueous mixtures of these surfactants with 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine (DMPC) was systematically studied by (31) P NMR spectroscopy. The surfactants endcapped with carbamate groups (SC-O(n) C4 and SC-O(t) C4 ) formed magnetically alignable bicelles over unprecedentedly wide ranges of conditions, in terms of temperature (from 21-23 to >90 °C), lipid/surfactant ratio (from 5 to 8), total lipid content (5-20 wt %), and lipid type [DMPC, 1,2-dilauroyl-sn-glycero-3-phosphatidylcholine (DLPC), or 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC)]...
December 5, 2016: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
Yuchi Liu, Xunbai Mei, Jielei Li, Nicola Lai, Xin Yu
The study aims to characterize age-associated changes in skeletal muscle bioenergetics by evaluating the response to ischemia-reperfusion in the skeletal muscle of the Goto-Kakizaki (GK) rats, a rat model of non-obese type 2 diabetes (T2D). (31)P magnetic resonance spectroscopy (MRS) and blood oxygen level-dependent (BOLD) MRI was performed on the hindlimb of young (12 weeks) and adult (20 weeks) GK and Wistar (control) rats. (31)P-MRS and BOLD-MRI data were acquired continuously during an ischemia and reperfusion protocol to quantify changes in phosphate metabolites and muscle oxygenation...
August 2016: Physiological Reports
Paula Sabater, Fabiola Zapata, Antonio Caballero, Néstor de la Visitación, Ibon Alkorta, José Elguero, Pedro Molina
Two-armed imidazolium-based anion receptors have been prepared. The central 2,7-disubstituted naphthalene ring features two photoactive anthracene end-capped side arms with central 2-bromoimidazolium or hydrogen-bonding imidazolium receptors. Combined emission and (1)H and (31)P NMR studies carried out in the presence of a wide variety of anions reveal that only HP2O7(3-), H2PO4(-), SO4(2-), and F(-) anions promoted noticeable changes. The halogen receptor 6(2+)·2PF6(-) acts as a selective fluorescent molecular sensor for H2PO4(-) anions, since only this anion promotes the appearance of the anthracene excimer emission band, whereas it remains unchanged in the presence of the other tested anions...
September 2, 2016: Journal of Organic Chemistry
Hongkun Zhang, Miaojun Xu, Bin Li
A novel phosphorus-containing compound diphenyl-(2,5-dihydroxyphenyl)-phosphine oxide defined as DPDHPPO was synthesized and used as flame retardant and curing agent for epoxy resins (EP). The chemical structure was well characterized by Fourier transform infrared (FTIR) spectroscopy, 1H, 13C and 31P nuclear magnetic resonance. The flame retardant properties, combusting performances and thermal degradation behaviors of the cured epoxy resins were investigated by limiting oxygen index (LOI), vertical burning tests (UL-94), cone calorimeter and thermogravimetric analysis (TGA) tests...
March 2016: Journal of Nanoscience and Nanotechnology
Tommaso Azzarito, Luana Lugini, Enrico Pierluigi Spugnini, Rossella Canese, Alessio Gugliotta, Stefano Fidanza, Stefano Fais
Tumor extracellular acidity is a hallmark of malignant cancers. Thus, in this study we evaluated the effects of the oral administration of a commercially available water alkalizer (Basenpulver®) (BP) on tumor growth in a syngenic melanoma mouse model. The alkalizer was administered daily by oral gavage starting one week after tumor implantation in CB57/BL mice. Tumors were calipered and their acidity measured by in vivo MRI guided 31P MRS. Furthermore, urine pH was monitored for potential metabolic alkalosis...
2016: PloS One
Christian Totland, Willy Nerdal, Signe Steinkopf
Coplanar and noncoplanar polychlorinated biphenyls (PCBs) are known to have different routes and degree of toxicity. Here, the effects of noncoplanar PCB 52 and coplanar PCB 77 present at 2 mol % in a model system consisting of POPC liposomes (50% hydrated) are investigated by solid-state (13)C and (31)P NMR at 298 K. Both PCBs intercalate horizontally in the outer part of the bilayer, near the segments of the acyl chain close to the glycerol group. Despite similar membrane locations, the coplanar PCB 77 shows little effect on the bilayer properties overall, except for the four nearest neighboring lipids, while the effect of PCB 52 is more dramatic...
August 2, 2016: Environmental Science & Technology
Brice Tiret, Emmanuel Brouillet, Julien Valette
With the increased spectral resolution made possible at high fields, a second, smaller inorganic phosphate resonance can be resolved on (31)P magnetic resonance spectra in the rat brain. Saturation transfer was used to estimate de novo adenosine triphosphate synthesis reaction rate. While the main inorganic phosphate pool is used by adenosine triphosphate synthase, the second pool is inactive for this reaction. Accounting for this new pool may not only help us understand (31)P magnetic resonance spectroscopy metabolic profiles better but also better quantify adenosine triphosphate synthesis...
September 2016: Journal of Cerebral Blood Flow and Metabolism
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