bluuebunny/crossref_metadata_2025_split huggingface dataset:
Piperazine Analogs of Naphthyridine‐3‐carboxamides and Indole‐2‐carboxamides: Novel 5‐HT3 Receptor Antagonists with Antidepressant‐Like Activity
Authors: Dhar Arghya K. , Mahesh Radhakrishnan , Jindal Ankur , Bhatt Shvetank 
Published: January 2015

AbstractSeries of piperazine analogs of naphthyridine‐3‐carboxamides and indole‐2‐carboxamides were designed using a ligand‐based approach with consideration of the pharmacophoric requirements for 5‐HT3 receptor antagonists. The title carboxamides were synthesized using appropriate synthetic routes. Initially, the 5‐HT3 receptor antagonistic activity of all the compounds was determined on isolated guinea pig ileum tissue against the 5‐HT3 agonist, 2‐methyl‐5‐hydroxytryptamine, which was denoted in the form of pA2 values. The structure–activity relationship regarding the influence of the aromatic part and basic moiety as features in the 5‐HT3 pharmacophore was derived. Among all the compounds screened, the piperazine derivatives of indole‐2‐carboxamide 13i and naphthyridine‐3‐carboxamide 8h exhibited prominent 5‐HT3 receptor antagonism with pA2 values of 7.5 and 7.3, respectively. Subsequent investigation of the antidepressant activities of selected compounds in the mouse forced swim test (FST) led to the identification of the piperazine analogs of indole‐2‐carboxamide 13i and naphthyridine‐3‐carboxamide 8h as the most promising compounds. Both 13i and 8h demonstrated significant reduction in the duration of immobility as compared to the control. Importantly, none of the tested compounds affected the baseline locomotion of mice at the tested dose levels.
A Ring‐Flippable Sugar as a Stimuli‐Responsive Component of Liposomes
Authors: Takeuchi Junji , Ohkubo Akihiro , Yuasa Hideya 
Published: January 2015

AbstractFor the development of a liposome that takes in and out a drug in response to stimuli, 2,4‐diaminoxylose (Xyl), which allows stimuli‐responsive conformational switches between 4C1 and 1C4, was incorporated into a lipid structure: Xyl derivatives with C8 and C16 methylene chains at the 1,3‐positions (C8Xyl and C16Xyl) were synthesized. 1H NMR spectroscopy indicates that the addition of Zn2+ and then H+ induces conformational switches from the chair (4C1) to the reverse chair (1C4) and 1C4‐to‐4C1, respectively, at Xyl; this leads to transformation of the lipids between linear and bent structures. Osmotic pressure and electron microscopy studies demonstrate that C8Xyl in water forms spherical solid aggregates (C8Xyl−Zn), which are converted into liposomes (C8Xyl+Zn) upon the addition of Zn2+, and C16Xyl forms liposomes regardless of the presence of Zn2+. The aggregates of C8Xyl±Zn incorporated a fluorophore and only C8Xyl+Zn released the content upon the addition of HCl. This study shows that Xyl could be a stimuli‐responsive component of a liposome.
Zur Orthotropie der physikalisch‐mechanischen Eigenschaften von Rotbuchenholz
Authors: Niemz Peter , Ozyhar Tomasz , Hering Stefan , Sonderegger Walter 
Published: January 2015

AbstractZunehmend wird versucht, Laubholz im Bauwesen einzusetzen, um größere Mengen stofflich zu verwerten und gleichzeitig die im Vergleich zum Nadelholz verbesserten mechanischen Eigenschaften des Laubholzes konstruktiv zu nutzen. Für die teilweise dazu erforderlichen Berechnungen der Verformung von Platten oder auch von Spannungen in Brettschichtholz (z. B. Vorausberechnung von eventuellen Delaminierungen oder der Alterung von Klebverbindungen) ist die Kenntnis der richtungsabhängigen Kennwerte des Holzes in den Hauptachsen längs, radial und tangential erforderlich. Dies betrifft die elastischen Kennwerte (E‐Modul, Schubmodul, Querdehnzahl), die Festigkeiten (auf Zug, Druck, Biegung und Scherung) und auch die Kennwerte für den Feuchte‐ und Wärmetransport (Diffusionskoeffizient, Wärmeleitfähigkeit). Für alle Kennwerte ist zudem die Kenntnis der Abhängigkeit von der Holzfeuchte und der Zeit notwendig. Ausgewählte Parameter für die Richtungs‐ und Feuchteabhängigkeit bei Rotbuchenholz werden für E‐Modul, Schubmodul und Querdehnzahl sowie die Wärmeleitfähigkeit und die Diffusionskonstante vorgestellt. Die Ergebnisse fassen an der ETH Zürich, Arbeitsgruppe Holzphysik, durchgeführte Arbeiten zur Thematik zusammen.The orthotropic behaviour of the physical‐mechanical properties of European beech woodHardwood is tried to be increasingly established in building industry in order to realise a larger material output and to take at once into account the structural advantage of the improved mechanical properties of hardwood in comparison to softwood. For the partially required calculations therefore of stress and strain in boards and glued‐laminated timbers (for example prognosis of potential delamination and aging of glued joints), it is essential to know the directional specific values of wood in the directions longitudinal, radial and tangential. This concerns the elastic specific values (YOUNG's modulus, shear modulus, POISSON's ratio), the specific values of strength (tension, compression, bending, shear) and also these of mass and heat flux (diffusion coefficient, thermal conductivity). Additionally, it is necessary to know the dependencies from moisture and duration for all specific values. Selected parameters for European beech wood will be presented concerning the dependencies of YOUNG's modulus, shear modulus, POISSON's ratio, thermal conductivity and diffusion coefficient from direction and moisture. The results summarize investigations on this topic realised at the Wood Physics Group of ETH Zurich.
Inkjet‐bioprinted acrylated peptides and PEG hydrogel with human mesenchymal stem cells promote robust bone and cartilage formation with minimal printhead clogging
Authors: Gao Guifang , Yonezawa Tomo , Hubbell Karen , Dai Guohao , Cui Xiaofeng 
Published: January 2015

AbstractInkjet bioprinting is one of the most promising additive manufacturing approaches for tissue fabrication with the advantages of high speed, high resolution, and low cost. The limitation of this technology is the potential damage to the printed cells and frequent clogging of the printhead. Here we developed acrylated peptides and co‐printed with acrylated poly(ethylene glycol) (PEG) hydrogel with simultaneous photopolymerization. At the same time, the bone marrow‐derived human mesenchymal stem cells (hMSCs) were precisely printed during the scaffold fabrication process so the cells were delivered simultaneously with minimal UV exposure. The multiple steps of scaffold synthesis and cell encapsulation were successfully combined into one single step using bioprinting. The resulted peptide‐conjugated PEG scaffold demonstrated excellent biocompatibility, with a cell viability of 87.9 ± 5.3%. Nozzle clogging was minimized due to the low viscosity of the PEG polymer. With osteogenic and chondrogenic differentiation, the bioprinted bone and cartilage tissue demonstrated excellent mineral and cartilage matrix deposition, as well as significantly increased mechanical properties. Strikingly, the bioprinted PEG‐peptide scaffold dramatically inhibited hMSC hypertrophy during chondrogenic differentiation. Collectively, bioprinted PEG‐peptide scaffold and hMSCs significantly enhanced osteogenic and chondrogenic differentiation for robust bone and cartilage formation with minimal printhead clogging.
Production of curcuminoids from tyrosine by a metabolically engineered Escherichia coli using caffeic acid as an intermediate
Authors: Rodrigues Joana L. , Araújo Rafael G. , Prather Kristala L. J. , Kluskens Leon D. , Rodrigues Ligia R. 
Published: January 2015

AbstractCurcuminoids are phenylpropanoids with high pharmaceutical potential. Herein, we report an engineered artificial pathway in Escherichia coli to produce natural curcuminoids through caffeic acid. Arabidopsis thaliana 4‐coumaroyl‐CoA ligase and Curcuma longa diketide‐CoA synthase (DCS) and curcumin synthase (CURS1) were used to produce curcuminoids and 70 mg/L of curcumin was obtained from ferulic acid. Bisdemethoxycurcumin and demethoxycurcumin were also produced, but in lower concentrations, by feeding p‐coumaric acid or a mixture of p‐coumaric acid and ferulic acid, respectively. Additionally, curcuminoids were produced from tyrosine through the caffeic acid pathway. To produce caffeic acid, tyrosine ammonia lyase from Rhodotorula glutinis and 4‐coumarate 3‐hydroxylase from Saccharothrix espanaensis were used. Caffeoyl‐CoA 3‐O‐methyltransferase from Medicago sativa was used to convert caffeoyl‐CoA to feruloyl‐CoA. Using caffeic acid, p‐coumaric acid or tyrosine as a substrate, 3.9, 0.3, and 0.2 mg/L of curcumin were produced, respectively. This is the first time DCS and CURS1 were used in vivo to produce curcuminoids and that curcumin was produced by feeding tyrosine. We have shown that curcumin can be produced using a pathway involvoing caffeic acid. This alternative pathway represents a step forward in the heterologous production of curcumin using E. coli.
Encapsulation of enzyme via one‐step template‐free formation of stable organic–inorganic capsules: A simple and efficient method for immobilizing enzyme with high activity and recyclability
Authors: Huang Renliang , Wu Mengyun , Goldman Mark J. , Li Zhi 
Published: January 2015

ABSTRACTEnzyme encapsulation is a simple, gentle, and general method for immobilizing enzyme, but it often suffers from one or more problems regarding enzyme loading efficiency, enzyme leakage, mechanical stability, and recyclability. Here we report a novel, simple, and efficient method for enzyme encapsulation to overcome these problems by forming stable organic–inorganic hybrid capsules. A new, facile, one‐step, and template‐free synthesis of organic–inorganic capsules in aqueous phase were developed based on PEI‐induced simultaneous interfacial self‐assembly of Fmoc‐FF and polycondensation of silicate. Addition of an aqueous solution of Fmoc‐FF and sodium silicate into an aqueous solution of PEI gave a new class of organic–inorganic hybrid capsules (FPSi) with multi‐layered structure in high yield. The capsules are mechanically stable due to the incorporation of inorganic silica. Direct encapsulation of enzyme such as epoxide hydrolase SpEH and BSA along with the formation of the organic–inorganic capsules gave high yield of enzyme‐containing capsules (∼1.2 mm in diameter), >90% enzyme loading efficiency, high specific enzyme loading (158 mg protein g−1 carrier), and low enzyme leakage (<3% after 48 h incubation). FPSi‐SpEH capsules catalyzed the hydrolysis of cyclohexene oxide to give (1R, 2R)‐cyclohexane‐1,2‐diol in high yield and concentration, with high specific activity (6.94 U mg−1 protein) and the same high enantioselectivity as the free enzyme. The immobilized SpEH demonstrated also excellent operational stability and recyclability: retaining 87% productivity after 20 cycles with a total reaction time of 80 h. The new enzyme encapsulation method is efficient, practical, and also better than other reported encapsulation methods. Biotechnol. Bioeng. 2015;112: 1092–1101. © 2015 Wiley Periodicals, Inc.
Synergetic Effects Leading to Coke‐Resistant NiCo Bimetallic Catalysts for Dry Reforming of Methane
Authors: Li Lidong , Anjum Dalaver H. , Zhu Haibo , Saih Youssef , Laveille Paco V. , D'Souza Lawrence , Basset Jean‐Marie 
Published: January 2015

AbstractA new dry reforming of methane catalyst comprised of NiCo bimetallic nanoparticles and a Mgx(Al)O support that exhibits high coke resistance and long‐term on‐stream stability is reported. The structural characterization by XRD, TEM, temperature‐programmed reduction, and BET analysis demonstrates that the excellent performance of this catalyst is ascribed to the synergy of various parameters, including metal‐nanoparticle size, metal–support interaction, catalyst structure, ensemble size, and alloy effects.
Fouling Resistance on Chemically Etched Hydrophobic Surfaces in Nucleate Pool Boiling
Authors: Hui Longfei , Liu Mingyan , Cai Yongwei , Lv Yan 
Published: January 2015

AbstractChemical etching, liquid phase deposition, and dipping techniques were utilized to fabricate highly hydrophobic micro‐ and nanoscale coating surfaces on stainless‐steel substrates. Heat transfer and fouling characteristics on these surfaces in pool boiling of deionized water and CaSO4 solution were studied. High roughness and hydrophobicity of coated surfaces were obtained on chemically etched substrates. Compared to the polished stainless‐steel surface, the chemically etched coating surface provided a three times enhanced nucleate boiling coefficient at high heat flux. Obvious decrease of CaSO4 fouling resistance was obtained on chemically etched surfaces due to the higher roughness and hydrophobicity before the fouling resistance reaches the asymptotic value. Slightly high asymptotic fouling resistance was observed compared with coating surfaces without chemical etching of substrates.
Nano‐/Microstructured Si/C Composite with High Tap Density as an Anode Material for Lithium‐Ion Batteries
Authors: Liu Jie , Zhang Qian , Wu Zhan‐Yu , Li Jun‐Tao , Huang Ling , Sun Shi‐Gang 
Published: January 2015

AbstractNanostructured Si materials are plagued by having a limited electrochemical performance and low tap density. Hence, we synthesized a nano‐/microstructured Si/C composite with Si nanoparticles uniformly embedded into a carbon matrix, which had a tap density 5.3 times higher than that of Si nanoparticles. The nano‐/microstructured Si/C composite shows a superior structural stability, which ensures a long cycle life with a capacity of 600 mAh g−1 after 1000 cycles at 420 mA g−1. Moreover, the carbon matrix can provide three‐dimensional electron‐transfer pathways for Si nanoparticles to improve the electronic conductivity. Therefore, the Si/C composite anode material also exhibits an outstanding rate capability, which can still deliver a capacity of 510 mAh g−1 at 5 C. Thus, the nano‐/microstructured Si/C composite with a high tap density possesses great potential in view of practical applications.
Precise Measurement of Long‐Range Heteronuclear Coupling Constants by a Novel Broadband Proton–Proton‐Decoupled CPMG‐HSQMBC Method
Authors: Timári István , Illyés Tünde Z. , Adams Ralph W. , Nilsson Mathias , Szilágyi László , Morris Gareth A. , Kövér Katalin E. 
Published: January 2015

AbstractA broadband proton–proton‐decoupled CPMG‐HSQMBC method for the precise and direct measurement of long‐range heteronuclear coupling constants is presented. The Zangger–Sterk‐based homodecoupling scheme reported herein efficiently removes unwanted proton–proton splittings from the heteronuclear multiplets, so that the desired heteronuclear couplings can be determined simply by measuring frequency differences between singlet maxima in the resulting spectra. The proposed pseudo‐1D/2D pulse sequences were tested on nucleotides, a metal complex incorporating P heterocycles, and diglycosyl (di)selenides, as well as on other carbohydrate derivatives, for the extraction of nJ(1H,31P), nJ(1H,77Se), and nJ(1H,13C) values, respectively.
Ring Opening of Donor–Acceptor Cyclopropanes with the Azide Ion: A Tool for Construction of N‐Heterocycles
Authors: Ivanov Konstantin L. , Villemson Elena V. , Budynina Ekaterina M. , Ivanova Olga A. , Trushkov Igor V. , Melnikov Mikhail Ya. 
Published: January 2015

AbstractA general method for ring opening of various donor–acceptor cyclopropanes with the azide ion through an SN2‐like reaction has been developed. This highly regioselective and stereospecific process proceeds through nucleophilic attack on the more‐substituted C2 atom of a cyclopropane with complete inversion of configuration at this center. Results of DFT calculations support the SN2 mechanism and demonstrate good qualitative correlation between the relative experimental reactivity of cyclopropanes and the calculated energy barriers. The reaction provides a straightforward approach to a variety of polyfunctional azides in up to 91 % yield. The high synthetic utility of these azides and the possibilities of their involvement in diversity‐oriented synthesis were demonstrated by the developed multipath strategy of their transformations into five‐, six‐, and seven‐membered N‐heterocycles, as well as complex annulated compounds, including natural products and medicines such as (−)‐nicotine and atorvastatin.
Fabrication of Highly Stable Glyco‐Gold Nanoparticles and Development of a Glyco‐Gold Nanoparticle‐Based Oriented Immobilized Antibody Microarray for Lectin (GOAL) Assay
Authors: Huang Li‐De , Adak Avijit K. , Yu Ching‐Ching , Hsiao Wei‐Chen , Lin Hong‐Jyune , Chen Mu‐Lin , Lin Chun‐Cheng 
Published: January 2015

AbstractThe design of high‐affinity lectin ligands is critical for enhancing the inherently weak binding affinities of monomeric carbohydrates to their binding proteins. Glyco‐gold nanoparticles (glyco‐AuNPs) are promising multivalent glycan displays that can confer significantly improved functional affinity of glyco‐AuNPs to proteins. Here, AuNPs are functionalized with several different carbohydrates to profile lectin affinities. We demonstrate that AuNPs functionalized with mixed thiolated ligands comprising glycan (70 mol %) and an amphiphilic linker (30 mol %) provide long‐term stability in solutions containing high concentrations of salts and proteins, with no evidence of nonspecific protein adsorption. These highly stable glyco‐AuNPs enable the detection of model plant lectins such as Concanavalin A, wheat germ agglutinin, and Ricinus communis Agglutinin 120, at subnanomolar and low picomolar levels through UV/Vis spectrophotometry and dynamic light scattering, respectively. Moreover, we develop in situ glyco‐AuNPs‐based agglutination on an oriented immobilized antibody microarray, which permits highly sensitive lectin sensing with the naked eye. In addition, this microarray is capable of detecting lectins presented individually, in other environmental settings, or in a mixture of samples. These results indicate that glyconanoparticles represent a versatile and highly sensitive method for detecting and probing the binding of glycan to proteins, with significant implications for the construction of a variety of platforms for the development of glyconanoparticle‐based biosensors.
ChemInform Abstract: Synthesis of 6‐Amino‐2,4‐dihydropyrano[2,3‐c]pyrazol‐5‐carbonitriles Catalyzed by Silica‐Supported Tetramethylguanidine under Solvent‐Free Conditions.
Authors: Atar Amol B. , Kim Jong Tae , Lim Kwon Taek , Jeong Yeon Tae 
Published: January 2015

AbstractThe title compounds are obtained by an efficient and environmentally benign four‐component, one‐pot cyclocondensation reaction of ethyl acetoacetate, hydrazine hydrate, aldehydes, and malononitriles.
Loss of ATRX and DAXX expression identifies poor prognosis for smooth muscle tumours of uncertain malignant potential and early stage uterine leiomyosarcoma
Authors: Slatter Tania L. , Hsia Howard , Samaranayaka Ari , Sykes Peter , Clow William (Bill) , Devenish Celia J. , Sutton Tim , Royds Janice A. , PC Philip , Cheung Annie N. , Hung Noelyn Anne 
Published: January 2015

AbstractUterine smooth muscle tumours of uncertain malignant potential (STUMP) are diagnostically and clinically challenging. The alternative lengthening of telomeres (ALT) telomere maintenance mechanism is associated with poor survival in soft tissue leiomyosarcoma. Time to first recurrence and survival were known for 18 STUMP and 43 leiomyosarcomata (LMS). These were screened for ALT telomere maintenance by the presence of ALT‐associated PML bodies (APBs) and for changes associated with the ALT phenotype, namely aberrant p53 expression, isocitrate dehydrogenase 1 mutation (R132H substitution) expression, mutant ATRX (αthalassemia/mental retardation syndrome X‐linked) expression and mutant DAXX (death‐domain‐associated protein) expression by immunohistochemistry (IHC). Overexpression of p16INK4A was examined immunohistologically in a subset of cases. Many of the tumours associated with death or recurrence demonstrated APBs commensurate with ALT telomere maintenance. However, all uterine STUMP (4/4), and vaginal STUMP (2/2) patients, and almost all LMS patients (88.4%, 23/26, including 90% (9/10) of stage 1 LMS cases), who had died of disease or who had recurrent disease, displayed loss of ATRX or DAXX expression. Loss of ATRX or DAXX expression identified poor prognosis (95% CI 2.1 to 40.8, p < 0.003), in the LMS group. Thus, loss of ATRX or DAXX expression in uterine smooth muscle tumours identifies a clinically aggressive molecular subtype of early stage LMS and when histopathological features are problematic such as in STUMP. As ATRX and DAXX IHC is readily performed in diagnostic laboratories these are potentially useful for routine histopathological classification and management.
Teenage acne and cancer risk in US women: A prospective cohort study
Authors: Zhang Mingfeng , Qureshi Abrar A. , Fortner Renée T. , Hankinson Susan E. , Wei Qingyi , Wang Li‐E , Eliassen A. Heather , Willett Walter C. , Hunter David J. , Han Jiali 
Published: January 2015

BACKGROUNDAcne reflects hormone imbalance and is a key component of several systemic diseases. We hypothesized that diagnosis of acne as a teenager might predict subsequent risk of hormone‐related cancers.METHODSWe followed 99,128 female nurses in the Nurses' Health Study II cohort for 20 years (1989‐2009) and used Cox proportional hazards models to estimate the hazard ratios (HRs) of 8 specific cancers (breast, thyroid, colorectal, ovarian, cervical, and endometrial cancers, melanoma, and non‐Hodgkin lymphoma) for women with a history of severe teenage acne.RESULTSAfter thoroughly adjusting for the previously known risk factors for each cancer, we found that among women with a history of severe teenage acne, the relative risk increased, with a multivariable‐adjusted HR of 1.44 (95% confidence interval [CI], 1.03‐2.01) for melanoma. We replicated this association in an independent melanoma case‐control study of 930 cases and 1026 controls (multivariable‐adjusted odds ratio, 1.27; 95% CI, 1.03‐1.56). We also found that in both studies the individuals with teenage acne were more likely to have moles (52.7% vs 50.1%, P < .001 in the cohort study; and 55.2% vs 45.1%, P = .004 in the case‐control study).CONCLUSIONSOur findings suggest that a history of teenage acne might be a novel risk factor for melanoma independent from the known factors, which supports a need for continued investigation of these relationships. Cancer 2015;121:1681–1687. © 2015 American Cancer Society.
The colorectal cancer mortality‐to‐incidence ratio as an indicator of global cancer screening and care
Authors: Sunkara Vasu , Hébert James R. 
Published: January 2015

BACKGROUNDDisparities in cancer screening, incidence, treatment, and survival are worsening globally. The mortality‐to‐incidence ratio (MIR) has been used previously to evaluate such disparities.METHODSThe MIR for colorectal cancer is calculated for all Organisation for Economic Cooperation and Development (OECD) countries using the 2012 GLOBOCAN incidence and mortality statistics. Health system rankings were obtained from the World Health Organization. Two linear regression models were fit with the MIR as the dependent variable and health system ranking as the independent variable; one included all countries and one model had the “divergents” removed.RESULTSThe regression model for all countries explained 24% of the total variance in the MIR. Nine countries were found to have regression‐calculated MIRs that differed from the actual MIR by >20%. Countries with lower‐than‐expected MIRs were found to have strong national health systems characterized by formal colorectal cancer screening programs. Conversely, countries with higher‐than‐expected MIRs lack screening programs. When these divergent points were removed from the data set, the recalculated regression model explained 60% of the total variance in the MIR.CONCLUSIONSThe MIR proved useful for identifying disparities in cancer screening and treatment internationally. It has potential as an indicator of the long‐term success of cancer surveillance programs and may be extended to other cancer types for these purposes. Cancer 2015;121:1563–1569. © 2015 American Cancer Society.