bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: N‐Heterocyclic Carbenes Mediated Cyano‐Phosphorylation of Ketones.
Authors: He Lin , Zhang Jing , Fan Ye‐Cheng , Du Guang‐Fen , Zhang Jie , Dai Bin 
Published: February 2014

AbstractThe title reaction affords various different substituted cyanohydrin‐O‐phosphates under mild conditions and the reaction can be easily scaled‐up.
ChemInform Abstract: Functionalized Alkenylzinc Reagents Bearing Carbonyl Groups: Preparation by Direct Metal Insertion and Reaction with Electrophiles.
Authors: Saemann Christoph , Schade Matthias A. , Yamada Shigeyuki , Knochel Paul 
Published: February 2014

AbstractThe present protocol avoids the drawbacks of established procedures, namely low reaction temperatures and use of expensive alkenyl iodides.
ChemInform Abstract: Regioselective Silyl/Acetate Exchange of Disaccharides Yields Advanced Glycosyl Donor and Acceptor Precursors.
Authors: Hsieh Hsiao‐Wu , Schombs Matthew W. , Witschi Mark A. , Gervay‐Hague Jacquelyn 
Published: February 2014

AbstractAcid concentration, thermal conditions, and microwave assistance mediate the silyl/acetate exchange reaction.
ChemInform Abstract: Inhibitory Constituents from the Aerial Parts of Polygala tenuifolia on LPS‐Induced NO Production in BV2 Microglia Cells
Authors: Shi Tian‐Xing , Wang Shu , Zeng Ke‐Wu , Tu Peng‐Fei , Jiang Yong 
Published: February 2014

Abstractisolation, structure determination and evaluation of inhibitory effects of five new phenolic glycosides, tenuisides A—E (I)—(III), new megastigmane glycoside, tenuiside F (IV), and seventeen known compounds on NO production in LPS‐activated BV‐2 microglia cells
ChemInform Abstract: Novel Ring A Rearranged Isomers with γ‐Lactone from the Fruits of Aphanamixis grandifolia.
Authors: Wang Xiao‐Bing , Zhang Yao , Wang Jun‐Song , Gu Yu‐Cheng , Kong Ling‐Yi 
Published: February 2014

AbstractAphagranols A (I) and B (II) are isolated and their structure is determined using spectroscopic methods and confirmed by comparison to their acetylated derivative.
ChemInform Abstract: Sydowiols A—C (I): Mycobacterium tuberculosis Protein Tyrosine Phosphatase (PtpA) Inhibitors from an East China Sea Marine‐Derived fungus, Aspergillus sydowii.
Authors: Capon Robert J. , et al. et al. 
Published: February 2014

AbstractThe sydowiols A (Ia) and C (Ic) are identified as M.
ChemInform Abstract: Enantioselective Syntheses of FR901464 (Ib) and Spliceostatin A (Ia): Potent Inhibitors of Spliceosome.
Authors: Ghosh Arun K. , Chen Zhi‐Hua 
Published: February 2014

AbstractA short and improved synthesis of the title compounds is presented in 19 and 20 total steps, respectively.
ChemInform Abstract: Additional Cytotoxic Substances Isolated from the Sponge‐Derived Gymnascella dankaliensis.
Authors: Amagata Taro , Tanaka Makoto , Yamada Takeshi , Chen Yi‐Pei , Minoura Katsuhiko , Numata Atsushi 
Published: February 2014

AbstractDankastin C (I) shows potent cell growth inhibitory activity against the murine P388 cell line.
A β‐Lactone‐Based Antivirulence Drug Ameliorates Staphylococcus aureus Skin Infections in Mice
Authors: Weinandy Franziska , Lorenz‐Baath Katrin , Korotkov Vadim S. , Böttcher Thomas , Sethi Shneh , Chakraborty Trinad , Sieber Stephan A. 
Published: February 2014

AbstractSkin infections caused by Staphylococcus aureus are a major clinical concern, especially if they are caused by multi‐resistant strains. In these cases, a spread into deeper soft tissues or the bloodstream results in life‐threatening conditions that are difficult to treat by conventional antibiotics. Previous in vitro experiments with a small β‐lactone‐based molecule demonstrated that antibiotic‐sensitive and ‐resistant S. aureus strains are effectively disarmed in their virulence and corresponding pathogenicity. In this work, in vivo mouse studies show that this methodology is effective for the treatment of skin abscesses in mice. A single dose of the β‐lactone significantly decreased abscess size even when applied 6 h post‐infection. Although the molecule requires pharmacological optimization (improved stability, for example), this study emphasizes the potential value of antivirulence therapies.
Comparison of secondary and primary thyroid cancer in adolescents and young adults
Authors: Goldfarb Melanie , Freyer David R. 
Published: February 2014

BACKGROUNDThyroid cancer is one of the 5 most common malignancies in adolescent and young adult (AYA) patients (ages 15‐39 years) and may develop de novo or in patients previously treated for cancer. This study compared the tumor characteristics, treatment, and overall survival (OS) of secondary malignant neoplasm (SMN) versus primary thyroid cancer in AYA patients.METHODSAll cases of AYA thyroid cancer contained in the 1998 to 2010 American College of Surgeons National Cancer Database were divided into 2 cohorts according to primary or secondary occurrence. Comparisons using appropriate statistical methods were performed.RESULTSOf 41,062 cases, 1349 (3.3%) had experienced a prior malignancy. Compared with cases of primary thyroid cancer, SMNs were more likely multifocal (odds ratio [OR] = 1.173, 95% confidence interval [CI] = 1.049‐1.313) microcarcinomas < 1 cm (OR = 1.496, 95% CI = 1.327‐1.687) with tall/columnar cells (OR = 2.187, 95% CI = 0.534‐0.692), of white race (OR = 2.643, 95% CI = 1.310‐5.331) and age 35‐39 years (OR = 1.239, 95% CI = 1.093‐1.404) and less likely female (OR = 0.608, 95% CI = 0.534‐0.692), Hispanic (OR = 0.779, 95% CI = 0.642‐0.946) age 15‐19 years (OR = 0.624, 95% CI = 0.510‐0.763) or 25‐29 years (OR = 0.711, 95% CI = 0.604‐0.837), or less likely > 4 cm in size (OR = 0.610, 95% CI = 0.493‐0.758). There was a 6.63‐fold (95% CI = 4.97‐8.86, P < .001) relative risk of death for secondary versus primary thyroid cancers after adjusting for demographic, tumor, and thyroid treatment factors. Only Hispanic origin, tall/columnar cell histology, and distant metastases decreased OS for SMNs.CONCLUSIONSAYAs who develop thyroid cancer as a SMN have a significantly decreased OS compared to AYAs with primary thyroid cancer. Multiple demographic and tumor differences exist between these 2 cohorts. Whether the outcome disparity results from previous cancer treatment or differences in biology, environment, or access to care are areas needing further investigation. Cancer 2014;120:1155–1161. © 2014 American Cancer Society.
Cryogenic Colocalization Microscopy for Nanometer‐Distance Measurements
Authors: Weisenburger Siegfried , Jing Bo , Hänni Dominik , Reymond Luc , Schuler Benjamin , Renn Alois , Sandoghdar Vahid 
Published: February 2014

AbstractThe main limiting factor in spatial resolution of localization microscopy is the number of detected photons. Recently we showed that cryogenic measurements improve the photostability of fluorophores, giving access to Angstrom precision in localization of single molecules. Here, we extend this method to colocalize two fluorophores attached to well‐defined positions of a double‐stranded DNA. By measuring the separations of the fluorophore pairs prepared at different design positions, we verify the feasibility of cryogenic distance measurement with sub‐nanometer accuracy. We discuss the important challenges of our method as well as its potential for further improvement and various applications.
Dispersion Characteristics and Aggregation in Titanate Nanowire Colloids
Authors: Horváth Endre , Grebikova Lucie , Maroni Plinio , Szabó Tamás , Magrez Arnaud , Forró László , Szilagyi Istvan 
Published: February 2014

AbstractTitanate nanowires (TiONWs) are synthesized through the hydrothermal method and characterized in acidic aqueous dispersions by using electrophoresis, dynamic light scattering, and atomic force microscopy. The TiONWs have a rodlike shape with an average length of about 600 nm and a thickness of 35 nm. They are positively charged under the conditions used. Their surface charge properties and aggregation are investigated in the presence of oppositely charged poly(styrene sulfonate) (PSS) polyelectrolyte. Charge neutralization followed by a subsequent charge reversal process is observed, which is attributed to the adsorption of PSS. The colloids are unstable near the charge neutralization point and stable at lower and higher PSS doses, in good qualitative agreement with the theory developed by Derjaguin, Landau, Verwey, and Overbeek (DLVO). The nanowires prefer to align along the walls, leading to “spaghetti‐like” oriented aggregates. The aggregation processes of bare and PSS‐coated TiONWs are monitored at different concentrations of an inert electrolyte; slow aggregation is found at low salt levels, whereas aggregation is rapid beyond the critical coagulation concentration, as predicted by the DLVO theory, which describes the colloid stability of the TiONWs adequately in all the systems investigated. Coating of the nanowires with the polyelectrolyte leads to a critical coagulation concentration 75 times higher than that of the bare titanates, indicating the enormous stabilizing effect of PSS.
Experimental and Theoretical Characterization of 5,10‐Diminoporphodimethenes: Dearomatized Porphyrinoids from Palladium‐Catalyzed Hydrazinations of 5,10‐Diarylporphyrins
Authors: Bašić Bruno , Locos Oliver B. , Rintoul Llew , Kan Jinglan , Jiang Jianzhuang , Arnold Dennis P. 
Published: February 2014

AbstractA new dearomatized porphyrinoid, 5,10‐diiminoporphodimethene (5,10‐DIPD), has been prepared by palladium‐catalyzed hydrazination of 5,10‐dibromo‐15,20‐bis(3,5‐di‐tert‐butylphenyl)porphyrin and its nickel(II) complex, by using ethyl and 4‐methoxybenzyl carbazates. The oxidative dearomatization of the porphyrin ring occurs in high yield. Further oxidation with 2,3‐dichloro‐5,6‐dicyanobenzoquinone forms the corresponding 5,10‐bis(azocarboxylates), thereby restoring the porphyrin aromaticity. The UV/visible spectra of the NiIIDIPDs exhibit remarkable redshifts of the lowest‐energy bands to 780 nm, and differential pulse voltammetry reveals a contracted electrochemical HOMO–LUMO gap of 1.44 V. Density functional theory (DFT) was used to calculate the optimized geometries and frontier molecular orbitals of model 5,10‐DIPDNi7cand 5,10‐bis(azocarboxylate)Ni8c. The conformations of the carbamate groups and the configurations of the CNZ unit were considered in conjunction with the NOESY spectra, to generate the global minimum geometry and two other structures with slightly higher energies. In the absence of solution data regarding conformations, ten possible local minimum conformations were considered forNi8c. Partition of the porphyrin macrocycle into tri‐ and monopyrrole fragments inNi7cand the inclusion of terminal conjugating functional groups generate unique frontier molecular orbital distributions and a HOMO–LUMO transition with a strong element of charge transfer from the monopyrrole ring. Time‐dependent DFT calculations were performed for the three lowest‐energy structures ofNi7candNi8c, and weighting according to their energies allowed the prediction of the electronic spectra. The calculations reproduce the lower‐energy regions of the spectra and the overall forms of the spectra with high accuracy, but agreement is not as good in the Soret region below 450 nm.
Isomerism of Cycloserine and Its Protonated Form
Authors: Fraschetti Caterina , Filippi Antonello , Borocci Stefano , Steinmetz Vincent , Speranza Maurizio 
Published: February 2014

AbstractA comprehensive ab initio investigation has been performed on the structure and stability of the isomers of cycloserine and its protonated forms in the unsolvated state. Many conformers of cycloserine in the ketonic (K), enolic (E4 and E2), and zwitterionic (Z7 and Z2) forms have been characterized. Enols E2 are only a few kilocalories per mole less stable than the K isomers. Enols E4, as well as Z7 and Z2 zwitterions, are several tens of kilocalories per mole less stable than K. All the above isomeric structures exhibit pronounced isoxazolidine ring puckering, which generates very rich conformeric landscapes. The relative stability of the conformers of K, E2, and E4 responds essentially to a complex balance between the attractive and repulsive electrostatic interactions among their functional groups. The preferred site of protonation of cycloserine in the gas phase has been also investigated computationally and experimentally by IR multiphoton dissociation (IRMPD) spectroscopy. The most basic center of cycloserine is the N(7) nitrogen atom (proton affinity (PA)=215.3 kcal mol−1). Another important basic site is the O(6) oxygen atom (PA=213.0 kcal mol−1). Their most populated conformers have been identified by IRMPD spectroscopy. Their predominance responds to the electrostatic interactions among the functional groups of the protonated molecule.
Synthesis of Zn‐doped talc in hydrothermal atmosphere
Authors: Catalano M. , Belluso E. , Miriello D. , Barrese E. , Bloise A. 
Published: February 2014

Zn‐doped talc were synthesized under hydrothermal conditions at constant reaction time and pressure of 160 hours and 2 kbar respectively, at three different temperatures (300, 500 and 650 °C) with pH‐values of 5 and 7. The starting materials and run products were characterized by X‐ray powder diffraction (XRPD), scanning electron microscopy with annexed energy‐dispersive spectrometry (SEM‐EDS), differential scanning calorimetry thermogravimetric analysis (DSC‐TG) and Fourier transform infrared (FT‐IR). The results showed that the temperature, pH‐value of the reaction mixture and amount of zinc in the starting mixture affected the growth of the Zn‐doped talc. When synthesized at low temperature talc presents low crystallinity, flawed morphology but higher content in zinc in its lattice. A thermal treatment at, or above 500 °C allowed a significant flaw reduction in talc morphology, a higher crystallinity and a lower content in dopant. When large amounts of Zn were present in the starting mixtures, Zn‐doped talc grew small in size and poorly shaped. The effect of Zn doping on some chemical/physical characteristics of the synthesized talc was also discussed.
Amine‐Functionalized Amino Acid‐based Ionic Liquids as Efficient and High‐Capacity Absorbents for CO2
Authors: Saravanamurugan Shunmugavel , Kunov‐Kruse Andreas J. , Fehrmann Rasmus , Riisager Anders 
Published: February 2014

AbstractIonic liquids (ILs) comprised of ammonium cations and anions of naturally occurring amino acids containing an additional amine group (e.g., lysine, histidine, asparagine, and glutamine) were examined as high‐capacity absorbents for CO2. An absorption capacity of 2.1 mol CO2 per mol of IL (3.5 mol CO2 per kg IL, 13.1 wt % CO2) was measured for [N66614][Lys] at ambient temperature and about 1 mol CO2 per mol of IL at 80 °C (under 1 bar of CO2). This demonstrated that desorption is possible under CO2‐rich conditions by temperature‐swing absorption; three consecutive sorption cycles were performed with the IL. The mechanistic and kinetic study of the absorption process was further substantiated by NMR spectroscopy and in situ attenuated total reflectance FTIR for [N66614][Lys] and the homologous phosphonium‐based IL [P66614][Lys]. This study revealed that carbamic acid was formed with CO2 in both ILs by chemisorption; however, the amino acid–carboxyl groups on the anion played an important—but different—catalytic role for the sorption kinetics in the two ILs. The origin of the cationic effect is speculated to be correlated with the strength of the ion interactions in the two ILs.
In search of antiaging modalities: Evaluation of mTOR‐ and ROS/DNA damage‐signaling by cytometry
Authors: Darzynkiewicz Zbigniew , Zhao Hong , Halicka H. Dorota , Li Jiangwei , Lee Yong‐Syu , Hsieh Tze‐Chen , Wu Joseph M. 
Published: February 2014

AbstractThis review presents the evidence in support of the IGF‐1/mTOR/S6K1 signaling as the primary factor contributing to aging and cellular senescence. Reviewed are also specific interactions between mTOR/S6K1 and ROS‐DNA damage signaling pathways. Outlined are critical sites along these pathways, including autophagy, as targets for potential antiaging (gero‐suppressive) and/or chemopreventive agents. Presented are applications of flow‐ and laser scanning‐ cytometry utilizing phospho‐specific Abs, to monitor activation along these pathways in response to the reported antiaging drugs rapamycin, metformin, berberine, resveratrol, vitamin D3, 2‐deoxyglucose, and acetylsalicylic acid. Specifically, effectiveness of these agents to attenuate the level of constitutive mTOR signaling was tested by cytometry and confirmed by Western blotting through measuring phosphorylation of the mTOR‐downstream targets including ribosomal protein S6. The ratiometric analysis of phosphorylated to total protein along the mTOR pathway offers a useful parameter reporting the effects of gero‐suppressive agents. In parallel, their ability to suppress the level of constitutive DNA damage signaling induced by endogenous ROS was measured. While the primary target of each of these agents may be different the data obtained on several human cancer cell lines, WI‐38 fibroblasts and normal lymphocytes suggest common downstream mechanism in which the decline in mTOR/S6K1 signaling and translation rate is coupled with a reduction of oxidative phosphorylation and ROS that leads to decreased oxidative DNA damage. The combined assessment of constitutive γH2AX expression, mitochondrial activity (ROS, ΔΨm), and mTOR signaling provides an adequate gamut of cell responses to test effectiveness of gero‐suppressive agents. Described is also an in vitro model of induction of cellular senescence by persistent replication stress, its quantitative analysis by laser scanning cytometry, and application to detect the property of the studied agents to attenuate the induction of senescence. Discussed is cytometric analysis of cell size and heterogeneity of size as a potential biomarker used to asses gero‐suppressive agents and longevity. © 2014 International Society for Advancement of Cytometry
Effect of the Mediterranean diet on heart failure biomarkers: a randomized sample from the PREDIMED trial
Authors: Fitó Montserrat , Estruch Ramón , Salas‐Salvadó Jordi , Martínez‐Gonzalez Miguel Angel , Arós Fernando , Vila Joan , Corella Dolores , Díaz Oscar , Sáez Guillermo , de la Torre Rafael , Mitjavila María‐Teresa , Muñoz Miguel Angel , Lamuela‐Raventós Rosa‐María , Ruiz‐Gutierrez Valentina , Fiol Miquel , Gómez‐Gracia Enrique , Lapetra José , Ros Emilio , Serra‐Majem Lluis , Covas María‐Isabel ,   on behalf of the PREDIMED Study Investigators
Published: February 2014

AimsScarce data are available on the effect of the traditional Mediterranean diet (TMD) on heart failure biomarkers. We assessed the effect of TMD on biomarkers related to heart failure in a high cardiovascular disease risk population.Methods and ResultsA total of 930 subjects at high cardiovascular risk (420 men and 510 women) were recruited in the framework of a multicentre, randomized, controlled, parallel‐group clinical trial directed at testing the efficacy of the TMD on the primary prevention of cardiovascular disease (The PREDIMED Study). Participants were assigned to a low‐fat diet (control, n = 310) or one of two TMDs [TMD + virgin olive oil (VOO) or TMD + nuts]. Depending on group assignment, participants received free provision of extra‐virgin olive oil, mixed nuts, or small non‐food gifts. After 1 year of intervention, both TMDs decreased plasma N‐terminal pro‐brain natriuretic peptide, with changes reaching significance vs. control group (P < 0.05). Oxidized low‐density lipoprotein decreased in both TMD groups (P < 0.05), the decrease in TMD + VOO group reaching significance vs. changes in control group (P = 0.003). Changes in lipoprotein(a) after TMD + VOO were less than those in the control group (P = 0.046) in which an increase (P = 0.035) was observed. No changes were observed in urinary albumin or albumin/creatinine ratio.ConclusionsIndividuals at high risk of cardiovascular disease (CVD) who improved their diet toward a TMD pattern reduced their N‐terminal pro‐brain natriuretic peptide compared with those assigned to a low‐fat diet. The same was found for in vivo oxidized low‐density lipoprotein and lipoprotein(a) plasma concentrations after the TMD + VOO diet. From our results TMD could be a useful tool to mitigate against risk factors for heart failure. From our results TMD could modify markers of heart failure towards a more protective mode.
CO Substitution Reactions of Diiron Complexes [{(μ‐SCH2)2X}Fe2(CO)6] and [{(μ‐SeCH2)2X}Fe2(CO)6] (X = O, CH2) with Ph2PCl/Me3NO to Give Ph2PCl‐, Ph2PNMe2‐, and Ph2PP(=O)Ph2‐Substituted Complexes Related to [FeFe] Hydrogenases
Authors: Song Li‐Cheng , Cao Meng , Du Zong‐Qiang , Feng Zhan‐Heng , Ma Zhen , Song Hai‐Bin 
Published: February 2014

AbstractDiiron carbonyl complex [{(μ‐SCH2)2O}Fe2(CO)6] (A) reacted with Ph2PCl and Me3NO in MeCN at room temperature to give the expected and unexpected Ph2PCl‐, Ph2PNMe2‐, and Ph2PP(=O)Ph2‐substituted complexes [{(μ‐SCH2)2O}Fe2(CO)5L] [1, L = Ph2PCl; 2, L = Ph2PNMe2; 3, L = Ph2PP(=O)Ph2], whereas complex [{(μ‐SCH2)2CH2}Fe2(CO)6] (B) reacted with Ph2PCl and Me3NO under similar conditions to afford only the unexpected complexes [{(μ‐SCH2)2CH2}Fe2(CO)5L] [4, L = Ph2PNMe2; 5, L = Ph2PP(=O)Ph2]. Similarly, complex [{(μ‐SeCH2)2O}Fe2(CO)6] (C) reacted with Ph2PCl and Me3NO in MeCN at room temperature to give the unexpected complexes [{(μ‐SeCH2)2O}Fe2(CO)5L] [6, L = Ph2PNMe2; 7, L = Ph2PP(=O)Ph2], and the corresponding unexpected complexes [{(μ‐SeCH2)2CH2}Fe2(CO)5L] [8, L = Ph2PNMe2; 9, L = Ph2PP(=O)Ph2] were produced by the reaction of complex [{(μ‐SeCH2)2CH2}Fe2(CO)6] (D) with Ph2PCl and Me3NO under similar conditions. The structures of 1–9 were characterized by elemental analysis and spectroscopy, and for 1–5 and 7–9 by X‐ray crystallography. Possible pathways for the formation of the functionalized phosphine‐substituted complexes 1–9 have been suggested. Complexes 1–9 can be regarded as models for [FeFe] hydrogenases as their structures are similar to the active site of [FeFe] hydrogenases, and some have been found to be catalysts for proton reduction to hydrogen in the presence of HOAc.
A Novel L‐Cysteine Electrochemical Sensor Using Sulfonated Graphene‐poly(3,4‐Ethylenedioxythiophene) Composite Film Decorated with Gold Nanoparticles
Authors: Wang Xiaoqiang , Wen Yangping , Lu Limin , Xu Jingkun , Zhang Long , Yao Yuanyuan , He Haohua 
Published: February 2014

AbstractBy exploiting the electrostatic interaction between positively charged 3,4‐ethylenedioxythiophene cation radicals and negatively charged sulfonated graphene (SG) sheets, we prepared a poly(3,4‐ethylenedioxythiophene)‐sulfonated graphene (SG‐PEDOT) composite film by a one‐step electrochemical process. The composite was further decorated with gold nanoparticles (AuNPs) and employed as an electrode material for the detection of L‐cysteine (Cys). The SG‐PEDOT composite film is shown to provide a rough surface for the electrodeposition of AuNPs and to improve substrate accessibility and interaction with Cys. Moreover, the AuNPs‐decorated composite exhibits better electrocatalytic performance than that of a SG‐PEDOT composite only. Under optimum experimental conditions, the amperometric current of the sensor is linearly related to the concentration of Cys in the 0.1 to 382 µM range, and the detection limit is 0.02 µM (at S/N=3). The modified electrode displays favorable selectivity, good stability and high reproducibility. The method was successfully applied to the detection of Cys in spiked human urine.