bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three‐dimensional matrix stiffness and adhesive ligands affect cancer cell response to toxins
Authors: Zustiak Silviya Petrova , Dadhwal Smritee , Medina Carlos , Steczina Sonette , Chehreghanianzabi Yasaman , Ashraf Anisa , Asuri Prashanth 
Published: July 2015

ABSTRACTThere is an immediate need to develop highly predictive in vitro cell‐based assays that provide reliable information on cancer drug efficacy and toxicity. Development of biomaterial‐based three‐dimensional (3D) cell culture models as drug screening platforms has recently gained much scientific interest as 3D cultures of cancer cells have been shown to more adequately mimic the in vivo tumor conditions. Moreover, it has been recognized that the biophysical and biochemical properties of the 3D microenvironment can play key roles in regulating various cancer cell fates, including their response to chemicals. In this study, we employed alginate‐based scaffolds of varying mechanical stiffness and adhesive ligand presentation to further explore the role of 3D microenvironmental cues on glioblastoma cell response to cytotoxic compounds. Our experiments suggested the ability of both matrix stiffness and cell‐matrix adhesions to strongly influence cell responses to toxins. Cells were found to be more susceptible to the toxins when cultured in softer matrices that emulated the stiffness of brain tissue. Furthermore, the effect of matrix stiffness on differential cell responses to toxins was negated by the presence of the adhesive ligand RGD, but regained when integrin‐based cell‐matrix interactions were inhibited. This study therefore indicates that both 3D matrix stiffness and cell‐matrix adhesions are important parameters in the design of more predictive in vitro platforms for drug development and toxicity screening. Biotechnol. Bioeng. 2016;113: 443–452. © 2015 Wiley Periodicals, Inc.
Development of a core outcome set for research and audit studies in reconstructive breast surgery
Authors: Potter S , Holcombe C , Ward J A , Blazeby J M , Brookes S T , Cawthorn S J , Harcourt D , Macefield R , Warr R , Weiler-Mithoff E , Williamson P R , Wilson S 
Published: July 2015

AbstractBackgroundAppropriate outcome selection is essential if research is to guide decision-making and inform policy. Systematic reviews of the clinical, cosmetic and patient-reported outcomes of reconstructive breast surgery, however, have demonstrated marked heterogeneity, and results from individual studies cannot be compared or combined. Use of a core outcome set may improve the situation. The BRAVO study developed a core outcome set for reconstructive breast surgery.MethodsA long list of outcomes identified from systematic reviews and stakeholder interviews was used to inform a questionnaire survey. Key stakeholders defined as individuals involved in decision-making for reconstructive breast surgery, including patients, breast and plastic surgeons, specialist nurses and psychologists, were sampled purposively and sent the questionnaire (round 1). This asked them to rate the importance of each outcome on a 9-point Likert scale from 1 (not important) to 9 (extremely important). The proportion of respondents rating each item as very important (score 7–9) was calculated. This was fed back to participants in a second questionnaire (round 2). Respondents were asked to reprioritize outcomes based on the feedback received. Items considered very important after round 2 were discussed at consensus meetings, where the core outcome set was agreed.ResultsA total of 148 items were combined into 34 domains within six categories. Some 303 participants (51·4 per cent) (215 (49·5 per cent) of 434 patients; 88 (56·4 per cent) of 156 professionals) completed and returned the round 1 questionnaire, and 259 (85·5 per cent) reprioritized outcomes in round 2. Fifteen items were excluded based on questionnaire scores and 19 were carried forward to the consensus meetings, where a core outcome set containing 11 key outcomes was agreed.ConclusionThe BRAVO study has used robust consensus methodology to develop a core outcome set for reconstructive breast surgery. Widespread adoption by the reconstructive community will improve the quality of outcome assessment in effectiveness studies. Future work will evaluate how these key outcomes should best be measured.
Measurement of ceftazidime concentration in human plasma by ultra‐performance liquid chromatography–tandem mass spectrometry. Application to critically ill patients and patients with osteoarticular infections
Authors: Rigo‐Bonnin Raül , Cobo‐Sacristán Sara , Padullés Ariadna , Ribera Alba , Arbiol‐Roca Ariadna , Murillo Óscar , Sabater‐Riera Joan , Alía Pedro 
Published: July 2015

AbstractCeftazidime is an antibiotic belonging to the third generation of the cephalosporin family. It is indicated in the treatment of serious, simple or mixed bacterial infections, and its administration in continuous or intermittent infusion allows optimization of the concentration of antibiotic to keep it above the minimum inhibitory concentration. We developed and validated a chromatographic method by ultra‐performance liquid chromatography–tandem mass spectrometry to measure ceftazidime concentration in human plasma. Following extraction with acetonitrile and 1,2‐dichloroethane, the chromatographic separation was achieved using an Acquity ® UPLC ® BEHTM (2.1 × 100 mm i.d., 1.7 µm) reverse‐phase C18 column, with a water–acetonitrile linear gradient containing 0.1% formic acid at a 0.4 mL/min flow rate. Ceftazidime and its internal standard (cefotaxime) were detected by electrospray ionization mass spectrometry in positive ion multiple reaction monitoring mode using mass‐to‐charge transitions of 547.0 → 467.9/396.1 and 456.0 → 395.8/324.1, respectively. The limit of quantification was 0.58 mg/L and linearity was observed in the range 0.58–160 mg/L. Coefficients of variation and absolute relative biases were <9.8 and 8.4%. The mean recovery for ceftazidime was 74.4 ± 8.1%. Evaluation of the matrix effect showed ion enhancement, and no carry‐over was observed. The validated method could be applied to daily clinical laboratory practice to measure the concentration of ceftazidime in plasma. Copyright © 2015 John Wiley & Sons, Ltd.
LC‐MS/MS determination of 1‐O‐acetylbritannilactone in rat plasma and its application to a preclinical pharmacokinetic study
Authors: Li Huajun , Li Wei , Yu Min , Jiang Ligang 
Published: July 2015

AbstractA novel, rapid and sensitive LC‐MS/MS method for the determination of 1‐O‐Acetylbritannilactone (ABL), a sesquiterpene lactone abundant in Inula britannica, was developed and validated using heteroclitin D as internal standard. Separation was achieved on a reversed phase Hypersil Gold C18 column (50 × 4.6 mm, i.d., 3.0 µm) using isocratic elution with methanol–5 mM ammonium acetate buffer aqueous solution (80:20, v/v) at a flow rate of 0.4 mL/min. Calibration curve was linear (r > 0.99) in a concentration range of 1.60–800 ng/mL with the lower limit of quantification of 1.60 ng/mL. Intra‐ and inter‐day accuracy and precision were validated by relative error (RE) and relative standard deviation (RSD) values, respectively, which were both less than ±15%. The validated method has been successfully applied to a pharmacokinetic study of ABL in rats. The elimination half‐lives were 0.412 ± 0.068, 0.415 ± 0.092 and 0.453 ± 0.071 h after a single intravenous administration of 0.14, 0.42, and 1.26 mg/kg ABL, respectively. The area under the plasma concentration–time curve from time zero to the last quantifiable time point and from time zero to infinity and the plasma concentrations at 2 min were linearly related to the doses tested. Copyright © 2015 John Wiley & Sons, Ltd.
Diagnostic accuracy for major depression in multiple sclerosis using self‐report questionnaires
Authors: Fischer Anja , Fischer Marcus , Nicholls Robert A. , Lau Stephanie , Poettgen Jana , Patas Kostas , Heesen Christoph , Gold Stefan M. 
Published: July 2015

AbstractObjectiveMultiple sclerosis and major depressive disorder frequently co‐occur but depression often remains undiagnosed in this population. Self‐rated depression questionnaires are a good option where clinician‐based standardized diagnostics are not feasible. However, there is a paucity of data on diagnostic accuracy of self‐report measures for depression in multiple sclerosis (MS). Moreover, head‐to‐head comparisons of common questionnaires are largely lacking. This could be particularly relevant for high‐risk patients with depressive symptoms. Here, we compare the diagnostic accuracy of the Beck Depression Inventory (BDI) and 30‐item version of the Inventory of Depressive Symptomatology Self‐Rated (IDS‐SR30) for major depressive disorder (MSS) against diagnosis by a structured clinical interview.MethodsPatients reporting depressive symptoms completed the BDI, the IDS‐SR30 and underwent diagnostic assessment (Mini International Neuropsychiatric Interview, M.I.N.I.). Receiver‐Operating Characteristic analyses were performed, providing error estimates and false‐positive/negative rates of suggested thresholds.ResultsData from n = 31 MS patients were available. BDI and IDS‐SR30 total score were significantly correlated (r = 0.82). The IDS‐SR30total score, cognitive subscore, and BDI showed excellent to good accuracy (area under the curve (AUC) 0.86, 0.91, and 0.85, respectively).ConclusionBoth the IDS‐SR30 and the BDI are useful to quantify depressive symptoms showing good sensitivity and specificity. The IDS‐SR30 cognitive subscale may be useful as a screening tool and to quantify affective/cognitive depressive symptomatology.
A Bi‐enzymatic Convergent Cascade for ε‐Caprolactone Synthesis Employing 1,6‐Hexanediol as a ‘Double‐Smart Cosubstrate’
Authors: Bornadel Amin , Hatti‐Kaul Rajni , Hollmann Frank , Kara Selin 
Published: July 2015

AbstractA bi‐enzymatic cascade consisting of a Baeyer–Villiger monooxygenase and an alcohol dehydrogenase (ADH) was designed in a convergent fashion to utilise two molar equivalents of cyclohexanone (CHO) and one equivalent of 1,6‐hexanediol as a ‘double‐smart cosubstrate’ to produce ε‐caprolactone (ECL) with water as sole by‐product. The convergent enzymatic cascade reaction reported herein, is performed at ambient conditions in water, is self‐sufficient with respect to cofactor, and incorporates all starting materials into the desired product, ECL. Among different enzymes explored, the reaction catalysed by cyclohexanone monooxygenase from Acinetobacter sp. NCIMB 9871 coupled with ADH from Thermoanaerobacter ethanolicus showed the best results, reaching 91 % conversion of CHO after 24 h with a product titre of 2 g L−1. Scale‐up of the coupled system (50 mL) performed better than the small‐scale reactions and >99 % conversion of CHO and ECL concentration of 20 mM were achieved within 18 h.
Nanoporosity, Inclusion Chemistry, and Spin Crossover in Orthogonally Interlocked Two‐Dimensional Metal–Organic Frameworks
Authors: Romero‐Morcillo Tania , De la Pinta Noelia , Callejo Lorena M. , Piñeiro‐López Lucía , Muñoz M. Carmen , Madariaga Gotzon , Ferrer Sacramento , Breczewski Tomasz , Cortés Roberto , Real José A. 
Published: July 2015

Abstract[Fe(tvp)2(NCS)2] (1) (tvp=trans‐(4,4′‐vinylenedipyridine)) consists of two independent perpendicular stacks of mutually interpenetrated two‐dimensional grids. This uncommon supramolecular conformation defines square‐sectional nanochannels (diagonal≈2.2 nm) in which inclusion molecules are located. The guest‐loaded framework 1@guest displays complete thermal spin‐crossover (SCO) behavior with the characteristic temperature T1/2 dependent on the guest molecule, whereas the guest‐free species 1 is paramagnetic whatever the temperature. For the benzene–guest derivatives, the characteristic SCO temperature T1/2 decreases as the Hammet σp parameter increases. In general, the 1@guest series shows large entropy variations associated with the SCO and conformational changes of the interpenetrated grids that leads to a crystallographic‐phase transition when the guest is benzonitrile or acetonitrile/H2O.
Pincer‐Type Complexes for Catalytic (De)Hydrogenation and Transfer (De)Hydrogenation Reactions: Recent Progress
Authors: Werkmeister Svenja , Neumann Jacob , Junge Kathrin , Beller Matthias 
Published: July 2015

AbstractPincer complexes are becoming increasingly important for organometallic chemistry and organic synthesis. Since numerous applications for such catalysts have been developed in recent decades, this Minireview covers progress in their use as catalysts for (de)hydrogenation and transfer (de)hydrogenation reactions during the last four years. Aside from noble‐metal‐based pincer complexes, the corresponding base metal complexes are also highlighted and their applications summarized.
Syntheses, Spectroscopic, Electrochemical, and Third‐Order Nonlinear Optical Studies of a Hybrid Tris{ruthenium(alkynyl)/(2‐phenylpyridine)}iridium Complex
Authors: Zhao Huajian , Simpson Peter V. , Barlow Adam , Moxey Graeme J. , Morshedi Mahbod , Roy Nivya , Philip Reji , Zhang Chi , Cifuentes Marie P. , Humphrey Mark G. 
Published: July 2015

AbstractThe synthesis of fac‐[Ir{N,C1′‐(2,2′‐NC5H4C6H3‐5′‐CC‐1‐C6H2‐3,5‐Et2‐4‐CCC6H4‐4‐CCH)}3] (10), which bears pendant ethynyl groups, and its reaction with [RuCl(dppe)2]PF6 to afford the heterobimetallic complex fac‐[Ir{N,C1′‐(2,2′‐NC5H4C6H3‐5′‐CC‐1‐C6H2‐3,5‐Et2‐4‐CCC6H4‐4‐CC‐trans‐[RuCl(dppe)2])}3] (11) is described. Complex 10 is available from the two‐step formation of iodo‐functionalized fac‐tris[2‐(4‐iodophenyl)pyridine]iridium(III) (6), followed by ligand‐centered palladium‐catalyzed coupling and desilylation reactions. Structural studies of tetrakis[2‐(4‐iodophenyl)pyridine‐N,C1′](μ‐dichloro)diiridium 5, 6, fac‐[Ir{N,C1′‐(2,2′‐NC5H4C6H3‐5′‐CC‐1‐C6H2‐3,5‐Et2‐4‐CCH)}3] (8), and 10 confirm ligand‐centered derivatization of the tris(2‐phenylpyridine)iridium unit. Electrochemical studies reveal two (5) or one (6–10) Ir‐centered oxidations for which the potential is sensitive to functionalization at the phenylpyridine groups but relatively insensitive to more remote derivatization. Compound 11 undergoes sequential Ru‐centered and Ir‐centered oxidation, with the potential of the latter significantly more positive than that of Ir(N,C′‐NC5H4‐2‐C6H4‐2)3. Ligand‐centered π–π* transitions characteristic of the Ir(N,C′‐NC5H4‐2‐C6H4‐2)3 unit red‐shift and gain in intensity following the iodo and alkynyl incorporation. Spectroelectrochemical studies of 6, 7, 9, and 11 reveal the appearance in each case of new low‐energy LMCT bands following formal IrIII/IV oxidation preceded, in the case of 11, by the appearance of a low‐energy LMCT band associated with the formal RuII/III oxidation process. Emission maxima of 6–10 reveal a red‐shift upon alkynyl group introduction and arylalkynyl π‐system lengthening; this process is quenched upon incorporation of the ligated ruthenium moiety on proceeding to 11. Third‐order nonlinear optical studies of 11 were undertaken at the benchmark wavelengths of 800 nm (fs pulses) and 532 nm (ns pulses), the results from the former suggesting a dominant contribution from two‐photon absorption, and results from the latter being consistent with primarily excited‐state absorption.
Carboxylated, Fe‐Filled Multiwalled Carbon Nanotubes as Versatile Catalysts for O2 Reduction and H2 Evolution Reactions at Physiological pH
Authors: Bracamonte M. Victoria , Melchionna Michele , Stopin Antoine , Giulani Angela , Tavagnacco Claudio , Garcia Yann , Fornasiero Paolo , Bonifazi Davide , Prato Maurizio 
Published: July 2015

AbstractThe development of new electrocatalysts for the oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) at physiological pH is critical for several fields, including fuel cells and biological applications. Herein, the assembly of an electrode based on carboxyl‐functionalised hydrophilic multiwalled carbon nanotubes (MWCNTs) filled with Fe phases and their excellent performance as electrocatalysts for ORR and HER at physiological pH are reported. The encapsulated Fe dramatically enhances the catalytic activity, and the graphitic shells play a double role of efficiently mediating the electron transfer to O2 and H2O reactants and providing a cocoon that prevents uncontrolled Fe oxidation or leaching.
Comprehensive Study of the Organic‐Solvent‐Free CDI‐Mediated Acylation of Various Nucleophiles by Mechanochemistry
Authors: Métro Thomas‐Xavier , Bonnamour Julien , Reidon Thomas , Duprez Anthony , Sarpoulet Jordi , Martinez Jean , Lamaty Frédéric 
Published: July 2015

AbstractAcylation reactions are ubiquitous in the synthesis of natural products and biologically active compounds. Unfortunately, these reactions often require the use of large quantities of volatile and/or toxic solvents, either for the reaction, purification or isolation of the products. Herein we describe and discuss the possibility of completely eliminating the use of organic solvents for the synthesis, purification and isolation of products resulting from the acylation of amines and other nucleophiles. Thus, utilisation of N,N′‐carbonyldiimidazole (CDI) allows efficient coupling between carboxylic acids and various nucleophiles under solvent‐free mechanical agitation, and water‐assisted grinding enables both the purification and isolation of pure products. Critical parameters such as the physical state and water solubility of the products, milling material, type of agitation (vibratory or planetary) as well as contamination from wear are analysed and discussed. In addition, original organic‐solvent‐free conditions are proposed to overcome the limitations of this approach. The calculations of various green metrics are included, highlighting the particularly low environmental impact of this strategy.
Experimental Evidence on the Formation of Ethene through Carbocations in Methanol Conversion over H‐ZSM‐5 Zeolite
Authors: Wang Chao , Yi Xianfeng , Xu Jun , Qi Guodong , Gao Pan , Wang Weiyu , Chu Yueying , Wang Qiang , Feng Ningdong , Liu Xiaolong , Zheng Anmin , Deng Feng 
Published: July 2015

AbstractThe methanol to olefins conversion over zeolite catalysts is a commercialized process to produce light olefins like ethene and propene but its mechanism is not well understood. We herein investigated the formation of ethene in the methanol to olefins reaction over the H‐ZSM‐5 zeolite. Three types of ethylcyclopentenyl carbocations, that is, the 1‐methyl‐3‐ethylcyclopentenyl, the 1,4‐dimethyl‐3‐ethylcyclopentenyl, and the 1,5‐dimethyl‐3‐ethylcyclopentenyl cation were unambiguously identified under working conditions by both solid‐state and liquid‐state NMR spectroscopy as well as GC‐MS analysis. These carbocations were found to be well correlated to ethene and lower methylbenzenes (xylene and trimethylbenzene). An aromatics‐based paring route provides rationale for the transformation of lower methylbenzenes to ethene through ethylcyclopentenyl cations as the key hydrocarbon‐pool intermediates.
Recent Progress toward the Introduction of Functionalized Difluoromethylated Building Blocks onto C(sp2) and C(sp) Centers
Authors: Belhomme Marie‐Charlotte , Besset Tatiana , Poisson Thomas , Pannecoucke Xavier 
Published: July 2015

AbstractFluorine chemistry is a field undergoing tremendous expansion. Although much attention has been paid to the introduction of the fluorine atom and the CF3 group, less interest has been devoted to the introduction of functionalized fluorinated building blocks, in sharp contrast with the high versatility of the fluorinated products. In this Minireview, the most relevant methods for the introduction of difluoromethylated building blocks are summarized. Access to difluoromethylated arenes, alkenes, and alkynes is highlighted and special attention is paid to explanation of the reaction mechanism.
Cobalt‐Catalyzed Cross‐Coupling of 3‐ and 4‐Iodopiperidines with Grignard Reagents
Authors: Gonnard Laurine , Guérinot Amandine , Cossy Janine 
Published: July 2015

AbstractA cobalt‐catalyzed cross‐coupling between 3‐ and 4‐iodopiperidines and Grignard reagents is disclosed. The reaction is an efficient, cheap, chemoselective, and flexible way to functionalize piperidines. This coupling was used as the key step to realize a short synthesis of (±)‐preclamol. Some mechanistic investigations were conducted that highlight the formation of radical intermediates.
Bifunctional Indenyl‐Derived Receptors for Fluoride Chelation and Detection
Authors: Tirfoin Rémi , Abdalla Joseph A. B. , Aldridge Simon 
Published: July 2015

AbstractAnion receptors based on a [CpFe(indenyl)] scaffold offer the possibility for the incorporation of adjacent Lewis acidic functions onto a six‐membered carbocyclic framework, while at the same time retaining the colorimetric/electrochemical reporter mechanisms available to synthetically simpler ferrocene systems. Thus, [CpFe(indenyl)] systems featuring mutually ortho BMes2 and PPh2Me+ substituents (with either 4,5 or 5,6 regiochemistry) are accessible which are capable of cooperative fluoride ion fixation. Simultaneous binding at the borane and phosphonium centres can be established by spectroscopic, structural and computational approaches, and is responsible for the favourable thermodynamics associated with F− uptake. Thus, in contrast to simple BMes2 systems, the binding of fluoride is found to be more favourable than the uptake of cyanide (which interacts only with the borane Lewis acid). Moreover, in the case of a 4‐(MePh2P)‐5‐(Mes2B)‐7‐Me‐indenyl derivative, fluoride chelation is signalled not only by a large cathodic shift in the FeII/FeIII potential (>500 mV in THF), but also by a distinct colour change from green (for the free receptor) to maroon for the adduct.
A New Synthetic Route to Microporous Silica with Well‐Defined Pores by Replication of a Metal–Organic Framework
Authors: Kondo Atsushi , Hall Anthony Shoji , Mallouk Thomas E. , Maeda Kazuyuki 
Published: July 2015

AbstractMicroporous amorphous hydrophobic silica materials with well‐defined pores were synthesized by replication of the metal–organic framework (MOF) [Cu3(1,3,5‐benzenetricarboxylate)2] (HKUST‐1). The silica replicas were obtained by using tetramethoxysilane or tetraethoxysilane as silica precursors and have a micro–meso binary pore system. The BET surface area, the micropore volume, and the mesopore volume of the silica replica, obtained by means of hydrothermal treatment at 423 K with tetraethoxysilane, are 620 m2g−1, 0.18 mL g−1, and 0.55 mL g−1, respectively. Interestingly, the silica has micropores with a pore size of 0.55 nm that corresponds to the pore‐wall thickness of the template MOF. The silica replica is hydrophobic, as confirmed by adsorption analyses, although the replica has a certain amount of silanol groups. This hydrophobicity is due to the unique condensation environment of the silica precursors in the template MOF.
Synthesis and Characterization of Carbazole‐Linked Porphyrin Tweezers
Authors: Chang Yi , Michelin Clément , Bucher Léo , Desbois Nicolas , Gros Claude P. , Piant Sébastien , Bolze Frédéric , Fang Yuanyuan , Jiang Xiaoqin , Kadish Karl M. 
Published: July 2015

AbstractHerein the synthesis, spectroscopic characterization, two‐photon absorption and electrochemical properties of 3,6‐disubstituted carbazole tweezers is reported. A dimer resulting from a Glaser homocoupling was isolated during a Sonogashira coupling reaction between a diethynyl‐carbazole spacer and a 5‐bromo‐triarylporphyrin and the properties of this original compound were compared with the 3,6‐disubstituted carbazole bisporphyrin tweezers. The dyads reported herein present a two‐photon absorption maximum at 920 nm with two‐photon absorption cross‐section in the 1200 GM range. Despite a strong linear absorption in the Soret region and moderate fluorescence quantum yield, they both lead to a high brightness reaching 30 000 M−1 cm−1.