bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association of Knee Effusion Detected by Physical Examination With Bone Marrow Lesions: Cross‐Sectional and Longitudinal Analyses of a Population‐Based Cohort
Authors: Cibere Jolanda , Guermazi Ali , Nicolaou Savvas , Esdaile John M. , Thorne Anona , Singer Joel , Wong Hubert , Kopec Jacek A. , Sayre Eric C. 
Published: April 2018

ObjectiveTo determine the association of effusion detected by physical examination with the prevalence of bone marrow lesions (BMLs) on magnetic resonance imaging (MRI), and the incidence/progression of BMLs over 3 years in subjects with knee osteoarthritis.MethodsA population‐based cohort with knee pain (n = 255) was assessed for effusion on physical examination. On MRI, BMLs were graded 0–3 (none, mild, moderate, severe), and incidence/progression was defined as a worsening of the sum of BML scores over 6 surfaces by ≥1 grade. We analyzed the full cohort and a mild disease subsample with a Kellgren/Lawrence (K/L) grade <3. Cross‐sectional logistic and longitudinal exponential regression analyses were performed, adjusted for age, sex, body mass index (BMI) and pain. We calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for effusion detected by physical examination versus BMLs (prevalence and incidence/progression).ResultsThe weighted mean age was 56.7 years, the mean BMI was 26.5, 56.3% were women, 20.1% had effusion on physical examination, and 80.7% had a K/L grade <3. Effusion on physical examination was significantly associated with prevalent BMLs in the full cohort (odds ratio [OR] 6.10 [95% confidence interval (95% CI) 2.77–13.44]) and in the K/L grade <3 cohort (OR 6.88 [95% CI 2.76–17.15]). In the full cohort, sensitivity, specificity, PPV, and NPV were 34.6, 92.5, 79.9, and 62.1%, respectively, and in the K/L <3 cohort 31.7, 94.0, 75.5, and 70.1%, respectively. Longitudinally, effusion on physical examination was not significantly associated with BML incidence/progression in the full cohort (hazard ratio [HR] 1.83 [95% CI 0.95–3.52]) or in the K/L grade <3 cohort (HR 1.73 [95% CI 0.69–4.33]). In the two cohorts, sensitivity, specificity, PPV, and NPV were 32.0, 82.2, 42.2, and 74.9%, respectively, and 21.2, 85.6, 30.1, and 78.8% respectively.ConclusionBMLs on MRI can be predicted from physical examination effusion cross‐sectionally, with a high PPV of 79.9%. Assessment for knee effusion on physical examination is useful for determining potential candidates with BMLs before costly MRI screening for recruitment into clinical trials.
Quantitative Signal Intensity Alteration in Infrapatellar Fat Pad Predicts Incident Radiographic Osteoarthritis: The Osteoarthritis Initiative
Authors: Wang Kang , Ding Changhai , Hannon Michael J. , Chen Zhongshan , Kwoh C. Kent , Hunter David J. 
Published: April 2018

ObjectiveTo determine whether infrapatellar fat pad (IPFP) signal intensity measures are predictive of incident radiographic osteoarthritis (ROA) over 4 years in the Osteoarthritis Initiative study.MethodsCase knees (n = 355), as defined by incident ROA, were matched 1:1 with control knees, according to sex, age, and radiographic status. T2‐weighted magnetic resonance images were assessed at P0 (the visit when incident ROA was observed on a radiograph), P1 (1 year prior to P0), and baseline and used to assess IPFP signal intensity semiautomatically. Conditional logistic regression analyses were performed to assess the risk of incident ROA associated with IPFP signal intensity alteration, after adjustment for covariates.ResultsThe mean age of the participants was 60.2 years, and most (66.7%) were female and overweight (mean body mass index 28.3 kg/m2). Baseline IPFP measures including the mean value and standard deviation of IPFP signal intensity, the mean value and standard deviation of IPFP high signal intensity, median and upper quartile values of IPFP high signal intensity, and the clustering effect of high signal intensity were associated with incident knee ROA over 4 years. All P1 IPFP measures were associated with incident ROA after 12 months. All P0 IPFP signal intensity measures were associated with ROA.ConclusionThe quantitative segmentation of high signal intensity in the IPFP observed in our study confirms the findings of previous work based on semiquantitative assessment, suggesting the predictive validity of semiquantitative assessment of IPFP high signal intensity. The IPFP high signal intensity alteration could be an important imaging biomarker to predict the occurrence of ROA.
Unravelling the Mechanism of the Ru/C‐Catalysed Isohexide and Ether Isomerization by Hydrogen Isotope Exchange
Authors: Engel Rebecca V. , Niemeier Johannes , Fink Anja , Rose Marcus 
Published: April 2018

AbstractIn this article we show that the catalytic isomerization of isohexide sugar alcohols as well as their respective ethers can occur by a hydride‐based mechanism rather than a dehydrogenation/re‐hydrogenation. C−H bonds in α‐position to hydroxy and ether groups are activated using Ru/C as solid catalyst at temperatures as high as 160 °C and above. Hydrogen isotope exchange experiments proved that a full hydride exchange and isomerization is possible for isohexides but unexpectedly also for their methyl ethers. This is of great importance as it proves the co‐existence of the both mechanisms for reactions that were so far assumed to occur solely by a dehydrogenation/re‐hydrogenation. Hence, this co‐existence should be taken into account for kinetic investigations of such reaction systems especially in the conversion of biomass‐based chemicals under hydrogenation conditions.magnified image
Optimizing the pretransplant regimen for autologous stem cell transplantation in acute myelogenous leukemia: Better outcomes with busulfan and melphalan compared with busulfan and cyclophosphamide in high risk patients autografted in first complete remission: A study from the acute leukemia working party of the EBMT
Authors: Gorin Norbert Claude , Labopin Myriam , Blaise Didier , Dumas Pierre‐Yves , Pabst Thomas , Trisolini Silvia Maria , Arcese William , Houhou Mohamed , Mohty Mohamad , Nagler Arnon 
Published: April 2018

AbstractAutologous stem cell transplantation remains a clinical option to consolidate some adult patients with acute myelogenous leukemia (AML) in first complete remission (CR1). In a small cohort of patients, we have previously shown better outcomes following Busulfan and Melphalan (BUMEL) over Busulfan and Cyclophosphamide (BUCY). To identify the subpopulations that might get the highest benefit with BUMEL, we designed a larger study. All adult patients with primary AML and available cytogenetics, autografted from January 2000 to December 2016 in CR1, were included: 1137 patients received BUCY and 512 BUMEL. All factors differing in distribution between the 2 conditioning groups were introduced in multivariate analyzes. In a primary analysis, we found an interaction between conditioning and the poor risk group defined as poor cytogenetics and/or presence of the FLT3‐ITD mutation. During analysis of the poor risk group, 176 patients received BUCY and 62 BUMEL. BUMEL was associated with a lower RI at 5 years (53% versus 69%, HR: 0.52, P = .002), a better Leukaemia‐free survival (LFS) (42% versus 25%, HR: 0.54, P = .002) and a better OS (54% versus 36%, HR: 0.61, P = .02). During analysis of the non poor risk group, 961 patients received BUCY and 450 BUMEL. At 5 years, the RI was 50% and 47%, the LFS 45% and 48% and the OS 56% and 60% respectively, with no significant difference. We conclude that BUMEL is the preferable conditioning regimen for the poor risk leukemic patients, while in AML patients without poor risk cytogenetics or FLT3 both conditioning regimens are valid.
Four N,O‐Bidentate‐Chelated Ligand‐Tunable Copper(II) Complexes: Synthesis, Structural Characterization and Exceptional Catalytic Properties for Chan–Lam Coupling Reactions
Authors: Jia Xuefeng , Peng Pai , Cui Jing , Xin Nana , Huang Xianqiang 
Published: April 2018

AbstractFour N,O‐bidentate chelating ligands [L1=N‐(4‐thiazolylmethyl)morpholine‐N‐oxide, L2=N‐(2‐pyridylmethyl)pyrrolidine‐N‐oxide, L3=N‐(4‐thiazolylmethyl)pyrrolidine‐N‐oxide, and L4=N‐(2‐pyridylmethyl)morpholine‐N‐oxide] were designed and synthesized. The treatment of N,O‐bidentate ligands with CuCl2 in ethanol at room temperature afforded four new copper complexes—[Cu(L1)2]Cl2 (I), [Cu(L2)2][CuCl4] (II), [Cu(L3)2Cl]2[CuCl2(H2O)2]Cl2⋅10 H2O (III) and [Cu(L4)2][Cu(L4)2(CH3OH)2][CuCl4]2 (IV)—which were fully characterized by single‐crystal X‐ray diffraction, IR spectroscopy and elemental analyses. Most interestingly, the single‐crystal X‐ray diffraction analyses revealed that the N,O‐bidentate ligands L1–L4 can tune the corresponding geometry configuration of copper atoms in complexes I–IV. The copper atoms in I and II showed four‐coordinated distorted square planar geometry, whereas the central copper atom in III adopted a distorted square pyramidal geometry. It should be noted that complex IV was constructed by a distorted square planar CuN2O2 unit, one octahedral CuN2O4 unit and two [CuCl4]2− anions. Importantly, these copper(II) complexes, especially complex IV, showed high catalytic activity in Chan–Lam coupling reactions of primary or secondary amines with arylboronic acid under mild conditions. Substrates with many functional groups were tolerated and the C–N coupling products were afforded in good to excellent yields (up to 96 % yield).
Iridium‐Catalyzed Direct Asymmetric Alkylation of Aniline Derivatives using 2‐Norbornene
Authors: Shirai Tomohiko , Okamoto Takakazu , Yamamoto Yasunori 
Published: April 2018

AbstractAn efficient and highly enantioselective direct alkylation process of acetanilides with 2‐norbornene using a bis(phosphoramidite) cationic Ir catalytic system (up to 99 % ee) has been reported. This methodology allows the facile preparation of enantiomerically enriched exo‐2‐(bicyclo[2.2.1]heptan‐2‐yl)anilines, which can be readily transformed into other functionalities.
Palladium‐Catalyzed para‐Selective Alkylation of Electron‐Deficient Arenes
Authors: Jiao Zhiwei , Lim Li Hui , Hirao Hajime , Zhou Jianrong Steve 
Published: April 2018

AbstractIntermolecular alkylations of electron‐deficient arenes proceed with good para selectivity. Palladium catalysts were used to generate nucleophilic alkyl radicals from alkyl halides, which then directly add onto the arenes. The arene scope and the site of alkylation are opposite to those of classical Friedel–Crafts alkylations, which prefer electron‐rich systems.
Phosphine‐Catalyzed Activation of Vinylcyclopropanes: Rearrangement of Vinylcyclopropylketones to Cycloheptenones
Authors: Wu Jun , Tang Yuhai , Wei Wen , Wu Yong , Li Yang , Zhang Junjie , Zheng Yuansuo , Xu Silong 
Published: April 2018

AbstractWe report a phosphine‐catalyzed activation of electron‐deficient vinylcyclopropanes (VCPs) to generate an ambident C5 synthon that is poised to undergo consecutive reactions. The utility of the activation is demonstrated in a phosphine‐catalyzed rearrangement of vinylcyclopropylketones to cycloheptenones in good yields with a broad substrate scope. Mechanistic investigations support a stepwise process comprising homoconjugate addition, water‐assisted proton transfer, and 7‐endo‐trig SN2′ ring closure.
Cyclic and Lasso Peptides: Sequence Determination, Topology Analysis, and Rotaxane Formation
Authors: Elashal Hader E. , Cohen Ryan D. , Elashal Heidi E. , Zong Chuhan , Link A. James , Raj Monika 
Published: April 2018

AbstractA broadly applicable chemical cleavage methodology to facilitate MS/MS sequencing was developed for macrocyclic and lasso peptides, which hold promise as exciting new therapeutics. Existing methods such as Edman degradation, CNBr cleavage, and enzymatic digestion are either limited in scope or completely fail in cleavage of constrained nonribosomal peptides. Importantly, the new method was utilized for synthesizing a unique peptide‐based rotaxane (both cyclic and threaded) from the lasso peptide, benenodin‐1 ΔC5.
The Cooperative Effect of Both Molecular and Supramolecular Chirality on Cell Adhesion
Authors: Liu Jinying , Yuan Feng , Ma Xiaoyu , Auphedeous Dang‐i Y. , Zhao Changli , Liu Chuntai , Shen Changyu , Feng Chuanliang 
Published: April 2018

AbstractAlthough helical nanofibrous structures have great influence on cell adhesion, the role played by chiral molecules in these structures on cells behavior has usually been ignored. The chirality of helical nanofibers is inverted by the odd–even effect of methylene units from homochiral l‐phenylalanine derivative during assembly. An increase in cell adhesion on left‐handed nanofibers and weak influence of cell behaviors on right‐handed nanofibers are observed, even though both were derived from l‐phenylalanine derivatives. Weak and negative influences on cell behavior was also observed for left‐ and right‐handed nanofibers derived from d‐phenylalanine, respectively. The effect on cell adhesion of single chiral molecules and helical nanofibers may be mutually offset.
Breslow Intermediates from Aromatic N‐Heterocyclic Carbenes (Benzimidazolin‐2‐ylidenes, Thiazolin‐2‐ylidenes)
Authors: Paul Mathias , Sudkaow Panyapon , Wessels Alina , Schlörer Nils E. , Neudörfl Jörg‐M. , Berkessel Albrecht 
Published: April 2018

AbstractWe report the first generation and characterization of elusive Breslow intermediates derived from aromatic N‐heterocyclic carbenes (NHCs), namely benzimidazolin‐2‐ylidenes (NMR, X‐ray analysis) and thiazolin‐2‐ylidenes (NMR). In the former case, the diamino enols were generated by reaction of the free N,N‐bis(2,6‐diisopropylphenyl)‐ and N,N‐bis(mesityl)‐substituted benzimidazolin‐2‐ylidenes with aldehydes while the dimer of 3,4,5‐trimethylthiazolin‐2‐ylidene served as the starting material in the latter case. The unambiguous NMR identification of the first thiazolin‐2‐ylidene‐based Breslow intermediate rests on double 13C labeling of both the NHC and the aldehyde component. The acyl anion reactivity was confirmed by benzoin formation with excess aldehyde.
Preparation of Cyclobutene Acetals and Tricyclic Oxetanes through Photochemical Tandem and Cascade Reactions
Authors: Buendia Julien , Chang Zong , Eijsberg Hendrik , Guillot Régis , Frongia Angelo , Secci Francesco , Xie Juan , Robin Sylvie , Boddaert Thomas , Aitken David J. 
Published: April 2018

AbstractWe describe a photochemical reaction using two starting materials, a cyclopent‐2‐enone and an alkene, which are transformed in a controlled manner via the initial [2+2]‐photocycloaddition adducts into cyclobutene aldehydes (conveniently trapped as stable acetals) or unprecedented angular tricyclic 4:4:4 oxetane‐containing skeletons. These compounds are formed through tandem or triple cascade photochemical reaction processes, respectively. Small libraries of each compound class were prepared, thus suggesting that this photochemistry approach opens new opportunities for synthesis design and for widening molecular diversity.
Solvent‐Mediated Functionalization of Benzofuroxan on Electron‐Rich Ruthenium Complex Platform
Authors: Ghosh Prabir , Dey Sanchaita , Panda Sanjib , Lahiri Goutam Kumar 
Published: April 2018

AbstractAn unprecedented reactivity profile of biochemically relevant R‐benzofuroxan (R=H, Me, Cl), with high structural diversity and molecular complexity on a selective {Ru(acac)2} (acac=acetylacetonate) platform, in conjugation with EtOH solvent mediation, is revealed. This led to the development of monomeric [RuIII(acac)2(L1R)] (1 a–1 c; L1R=2‐nitrosoanilido derivatives) and dimeric [{RuII(acac)2}2(L2R)] (2 a–2 b; L2R=(1E,2E)‐N1,N2‐bis(2‐nitrosophenyl)ethane‐1,2‐diimine derivatives) complexes in one pot with a change in the metal redox conditions. The functionalization of benzofuroxan in 1 and 2 implied in situ reduction of N=O to NH− in the former and solvent‐assisted multiple N−C coupling in the latter. The aforesaid transformation processes were authenticated through structural elucidation of representative complexes, and evaluated by their spectroscopic/electrochemical features, along with C2D5OD labeling and monitoring of the impact of substituents (R) in the benzofuroxan framework on the product distribution process. The noninnocent potential of newly developed L1 and L2 in 1 and 2, respectively, was also probed by spectroelectrochemistry in combination with DFT calculations.
The profiling and identification of chemical components, prototypes and metabolites of Run‐zao‐zhi‐yang capsule in rat plasma, urine and bile by an UPLC‐Q‐TOF/MSE‐based high‐throughput strategy
Authors: Lin Shan , Yue Xinyi , Ouyang Danwei , Li Quan , Yang Peiming 
Published: April 2018

AbstractRun‐zao‐zhi‐yang (RZZY) capsule, a traditional Chinese medicine formula, is popularly used for the treatment of dermatitis and eczema. However, few studies have been carried out on RZZY and its metabolites. In this study, we developed a three‐step strategy to rapidly characterize the chemical constituents and metabolites of RZZY using ultra‐high‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry. A total of 41 chemical components were characterized from RZZY. Among these, there are 11 flavonoids, six alkaloids, six stilbene glycosides, five anthraquinones and 13 other compounds. In addition, 18 prototypes and 35 metabolites were detected in rat plasma, urine and bile. This study offers an applicable approach for high‐throughput profiling and identification of chemical components and metabolites derived from traditional Chinese medicine formula in vivo, and also provides essential data for exploring bioactive ingredients and action mechanisms of RZZY.
Construction of a Holliday Junction in Small Circular DNA Molecules for Stable Motifs and Two‐Dimensional Lattices
Authors: Guo Xin , Wang Xue‐Mei , Wei Shuai , Xiao Shou‐Jun 
Published: April 2018

AbstractDesign rules for DNA nanotechnology have been mostly learnt from using linear single‐stranded (ss) DNA as the source material. For example, the core structure of a typical DAO (double crossover, antiparallel, odd half‐turns) tile for assembling 2D lattices is constructed from only two linear ss‐oligonucleotide scaffold strands, similar to two ropes making a square knot. Herein, a new type of coupled DAO (cDAO) tile and 2D lattices of small circular ss‐oligonucleotides as scaffold strands and linear ss‐oligonucleotides as staple strands are reported. A cDAO tile of cDAO‐c64nt (c64nt: circular 64 nucleotides), shaped as a solid parallelogram, is constructed with a Holliday junction (HJ) at the center and two HJs at both poles of a c64nt; similarly, cDAO‐c84nt, shaped as a crossed quadrilateral composed of two congruent triangles, is formed with a HJ at the center and four three‐way junctions at the corners of a c84nt. Perfect 2D lattices were assembled from cDAO tiles: infinite nanostructures of nanoribbons, nanotubes, and nanorings, and finite nanostructures. The structural relationship between the visible lattices imaged by AFM and the corresponding invisible secondary and tertiary molecular structures of HJs, inclination angle of hydrogen bonds against the double‐helix axis, and the chirality of the tile can be interpreted very well. This work could shed new light on DNA nanotechnology with unique circular tiles.
CFD Simulation of a Drowning‐out Crystallizer for Hexanitrohexaazaisowurtzitane
Authors: Oh Dong-Hoon , Jung Woo-Young , Jun Rak-Young , Lee Chang-Ha , Oh Min , Kim Kwang-Joo 
Published: April 2018

AbstractHexanitrohexaazaisowurtzitane (HNIW) is widely used for explosives, filling warheads, and solid propellants due to its high energy density and no halogen content. A pilot‐scale drowning‐out crystallizer is suggested to produce ε‐form HNIW and computational fluid dynamics simulation (CFD) was carried out. Acetone and isopropyl alcohols served as solvent and antisolvent, respectively. Population balance with quadratic method of moment was employed for the prediction of crystal size distribution and the results were compared with experimental data. The driving force of antisolvent crystallization includes impeller speed, ratio of antisolvent to solvent, and feed flow rate. A case study with various operating conditions was performed to identify the influence of such driving forces on crystal mean diameter. The aim was a scale‐up of the antisolvent crystallization process based on experimental results and CFD simulation.
Mesoporous MFI Zeolite with a 2D Square Structure Directed by Surfactants with an Azobenzene Tail Group
Authors: Shen Xuefeng , Mao Wenting , Ma Yanhang , Peng Honggen , Xu Dongdong , Wu Peng , Han Lu , Che Shunai 
Published: April 2018

AbstractMesoporous MFI zeolites (MMZs) have been constructed by using the surfactant‐containing azobenzene segment in the hydrophobic tail. The cylindrical π–π stacking of azeobenzene groups is considered to be the key factor to form the ordered mesostructure through cooperative structural matching and the rearrangement of MFI frameworks. The mesostructure has been tuned from a disordered hierarchical arrangement into an ordered 2D square p4mm structure by changing the length of the alkyl chain between the diquaternary ammonium head group and azobenzene group. The geometric matching between the MFI zeolitic framework and the alkyl chain length plays an important role in the construction of the crystallographically correlated mesostructure with 2D square ordering. A combination of X‐ray diffraction patterns and electron microscopy studies provides visible evidence for the mesostructural transformation from a short‐range hexagonal or lamellar ordering to 2D square mesostructure.
(2R,5S)‐Theaspirane Identified as the Kairomone for the Banana Weevil, Cosmopolites sordidus, from Attractive Senesced Leaves of the Host Banana, Musa spp.
Authors: Abagale Samson A. , Woodcock Christine M. , Hooper Antony M. , Caulfield John C. , Withall David , Chamberlain Keith , Acquaah Samuel O. , Van Emden Helmut , Braimah Haruna , Pickett John A. , Birkett Michael A. 
Published: April 2018

AbstractThe principal active component produced by highly attractive senesced host banana leaves, Musa spp., for the banana weevil, Cosmopolites sordidus, is shown by coupled gas chromatography‐electroantennography (GC‐EAG), coupled GC‐mass spectrometry (GC‐MS), chemical synthesis and coupled enantioselective (chiral) GC‐EAG to be (2R,5S)‐theaspirane. In laboratory behaviour tests, the synthetic compound is as attractive as natural host leaf material and presents a new opportunity for pest control.
Homogeneous Palladium‐Catalyzed Transfer Hydrogenolysis of Benzylic Alcohols Using Formic Acid as Reductant
Authors: Ciszek Benjamin , Fleischer Ivana 
Published: April 2018

AbstractWe report the first homogeneous palladium‐based transfer hydrogenolysis of benzylic alcohols using an in situ formed palladium‐phosphine complex and formic acid as reducing agent. The reaction requires a catalyst loading as low as only 1 mol % of palladium and just a slight excess of reductant to obtain the deoxygenated alkylarenes in good to excellent yields. Besides demonstrating the broad applicability for primary, secondary and tertiary benzylic alcohols, a reaction intermediate could be identified. Additionally, it could be shown that partial oxidation of the applied phosphine ligand was beneficial for the course of the reaction, presumably by stabilizing the active catalyst. Reaction profiles and catalyst poisoning experiments were used to characterize the catalyst, the results of which indicate a homogeneous metal complex as the active species.