bluuebunny/crossref_metadata_2025_split huggingface dataset:
Engineering surface hydrophobicity improves activity of Bacillus thermocatenulatus lipase 2 enzyme
Authors: Tang Ting , Yuan Chongli , Hwang Hyun‐Tae , Zhao Xuebing , Ramkrishna Doraiswami , Liu Dehua , Varma Arvind 
Published: June 2015

AbstractBacillus thermocatenulatus lipase 2 (BTL2) is a promising industrial enzyme used in biodiesel production. Although BTL2 has high thermostability and good resistance to organic solvents, the activity of BTL2 is suboptimal for industrial processes. To improve BTL2 activity, we engineered BTL2 lipase by modulating hydrophobicity of its lid domain. Through site‐directed mutagenesis, we constructed three mutants, namely Y225F+S232A, S232A+T236V and Q185L, to cover all uncharged hydrophilic amino acids within the lid domain. Activities of these mutants were characterized. Our findings suggest that one mutant (Y225F+S232A) showed ∼35% activity increase in catalyzing heterogeneous hydrolytic reactions relevant for industrial applications. A mathematical framework was established to account for different molecular events that contribute to the observed apparent catalytic activities. Increases in hydrophobicity of lid domains were associated with increased interfacial adsorption of lipases and lower molecular enzymatic activities. The measured apparent activities of lipases include contributions from both events. Lid hydrophobicity can thus result in different changes in lipase activities depending on the mutation site. Our work demonstrates the feasibility of increasing BTL2 activity by modulating the hydrophobicity of lid domains and provides some guidelines for further improving BTL2 activity.
Method for generation of peptide‐specific igy antibodies directed to Staphylococcus aureus extracellular fibrinogen binding protein epitope
Authors: Walczak Maciej , Grzywa Renata , Łupicka‐Słowik Agnieszka , Skoreński Marcin , Bobrek Kamila , Nowak Daria , Boivin Stephane , Brown Eric L. , Oleksyszyn Józef , Sieńczyk Marcin 
Published: June 2015

ABSTRACTThe IgY antibodies offer an attractive alternative to mammalian IgGs in research, diagnosis and medicine. The isolation of immunoglobulin Y from the egg yolks is efficient and economical, causing minimal suffering to animals. Here we present the methodology for the production of IgY antibodies specific to Staphylococcus aureus fibrinogen binding protein (Efb) and its peptidyl epitope (spanning residues 127–140). The Efb is an extracellular, adhesion protein which binds both human fibrinogen and complement C3 protein thus contributing to the high infectious potential of this pathogen. The selected epitope of Efb protein is responsible for the interaction with C3. The immunochemical characterization of both anti‐Efb and epitope‐specific IgY antibodies revealed their similar avidity, titer, and reactivity profile, although some differences in the hen's immune response to administered antigens is discussed. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 104: 552–559, 2015.
Case-mix analysis and variation in rates of non-surgical treatment of older women with operable breast cancer
Authors: Morgan J , Richards P , Ward S , Francis M , Lawrence G , Collins K , Reed M , Wyld L 
Published: June 2015

Abstract

Background
Non-surgical management of older women with oestrogen receptor (ER)-positive operable breast cancer is common in the UK, with up to 40 per cent of women aged over 70 years receiving primary endocrine therapy. Although this may be appropriate for frailer patients, for some it may result in treatment failure, contributing to the poor outcomes seen in this age group. Wide variation in the rates of non-operative management of breast cancer in older women exists across the UK. Case mix may explain some of this variation in practice.

Methods
Data from two UK regional cancer registries were analysed to determine whether variation in treatment observed between 2002 and 2010 at hospital and clinician level persisted after adjustment for case mix. Expected case mix-adjusted surgery rates were derived by logistic regression using the variables age, proxy Charlson co-morbidity score, deprivation quintile, method of cancer detection, tumour size, stage, grade and node status.

Results
Data on 17 129 women aged 70 years or more with ER-positive operable breast cancer were analysed. There was considerable variation in rates of surgery at both hospital and clinician level. Despite adjusting for case mix, this variation persisted at hospital level, although not at clinician level.

Conclusion
This study demonstrates variation in selection criteria for older women for operative treatment of early breast cancer, indicating that some older women may be undertreated or overtreated, and may partly explain the inferior disease outcomes in this age group. It emphasizes the urgent need for evidence-based guidelines for treatment selection criteria in older women with breast cancer.
Simultaneous quantification of atenolol and chlorthalidone in human plasma by ultra‐performance liquid chromatography–tandem mass spectrometry
Authors: Shah Jaivik V. , Patel Daxesh P. , Shah Priyanka A. , Sanyal Mallika , Shrivastav Pranav S. 
Published: June 2015

AbstractA simple, sensitive and reproducible ultra‐performance liquid chromatography–tandem mass spectrometry method has been developed for the simultaneous determination of atenolol, a β‐adrenergic receptor‐blocker and chlorthalidone, a monosulfonamyl diuretic in human plasma, using atenolol‐d7 and chlorthalidone‐d4 as the internal standards (ISs). Following solid‐phase extraction on Phenomenex Strata‐X cartridges using 100 μL human plasma sample, the analytes and ISs were separated on an Acquity UPLC BEH C18 (50 mm × 2.1 mm, 1.7 µm) column using a mobile phase consisting of 0.1% formic acid–acetonitrile (25:75, v/v). A tandem mass spectrometer equipped with electrospray ionization was used as a detector in the positive ionization mode for both analytes. The linear concentration range was established as 0.50–500 ng/mL for atenolol and 0.25–150 ng/mL for chlorthalidone. Extraction recoveries were within 95–103% and ion suppression/enhancement, expressed as IS‐normalized matrix factors, ranged from 0.95 to 1.06 for both the analytes. Intra‐batch and inter‐batch precision (CV) and accuracy values were 2.37–5.91 and 96.1–103.2%, respectively. Stability of analytes in plasma was evaluated under different conditions, such as bench‐top, freeze–thaw, dry and wet extract and long‐term. The developed method was superior to the existing methods for the simultaneous determination of atenolol and chlorthalidone in human plasma with respect to the sensitivity, chromatographic analysis time and plasma volume for processing. Further, it was successfully applied to support a bioequivalence study of 50 mg atenolol + 12.5 mg chlorthalidone in 28 healthy Indian subjects. Copyright © 2015 John Wiley & Sons, Ltd.
Foldamers as Anticancer Therapeutics: Targeting Protein–Protein Interactions and the Cell Membrane
Authors: Fahs Sara , Patil‐Sen Yogita , Snape Timothy J. 
Published: June 2015

AbstractTargeting important protein–protein interactions involved in carcinogenesis or targeting the cell membrane of a cancer cell directly are just two of the ways in which foldamers (oligomeric molecules that fold into distinct shapes in solution) hold considerable potential in the treatment of cancer. From mimicking the local topography of the helical compound of interest by using covalently constrained foldamers to mimicking the topography of the natural helix such that the positions of key functional motifs are in an identical spatial orientation to match those presented by the original α‐helix, synthetic foldamers have been used to mimic the natural foldamers that interact with proteins or the cell membrane. These targeted approaches have become established over a timeframe of more than a decade, and they continue to be included in the assortment of cancer targets being studied and the arsenal of chemotherapy compounds in development. These approaches are reviewed herein.
Prenatal diagnosis of X‐linked adrenoleukodystrophy associated with isolated pericardial effusion
Authors: Traficante Giovanna , Biagiotti Roberto , Andreucci Elena , Di Tommaso Mariarosaria , Provenzano Aldesia , Cariati Ettore , Giglio Sabrina 
Published: June 2015

Key Clinical MessageThis is the first reported case of fetal pericardial effusion in association with X‐linked adrenoleukodystrophy and hypocortisolism from a nonautoimmune cause. Our hypothesis is that in experienced hands and after accurate genetic counseling, isolated pericardial effusion can constitute an indication for a severe metabolic disease.
A case of delayed hemothorax with an inferior phrenic artery injury detected and treated endovascularly
Authors: Yamanashi Keiji , Nakao Shota , Idoguchi Koji , Matsuoka Tetsuya 
Published: June 2015

Key Clinical MessageWe report the rare case of delayed hemothorax (DHX) with an inferior phrenic artery (IPA) injury due to blunt thoracic trauma. Our case suggests that DHX almost always occurs early after injury, and endovascular treatment is an effective procedure for traumatic hemothorax including DHX.
The Carbocation: A Forgotten Lewis Acid Catalyst
Authors: Naidu Veluru Ramesh , Ni Shengjun , Franzén Johan 
Published: June 2015

AbstractA Lewis acid that has received negligible attention as a catalyst is the carbocation. The carbocation is isoelectronic to boron and owes its Lewis acidity to a low‐lying empty pC orbital. In terms of reactivity and stability carbocations are very versatile Lewis acids, from the extremely unstable methylium cation to the water‐stable tris(N,N‐dimethylaniline) methylium ion (crystal violet). Although the Lewis acid properties of carbocations have been extensively studied since the discovery of the tropolium ion more than 130 years ago there is only a handful examples on the application of carbocations as Lewis acid catalysts. Herein, the research on triarylmethylium (trityl)‐cation catalysis is summarized. In light of the reports the trityl ion emerges as a highly efficient and highly versatile Lewis acid catalyst capable of catalyzing different classes of reactions often with high selectivity and low catalyst loadings (for some reactions down to ppm levels).
Effect of Cobalt Particle Size on Acetone Steam Reforming
Authors: Sun Junming , Zhang He , Yu Ning , Davidson Stephen , Wang Yong 
Published: June 2015

AbstractCarbon‐supported cobalt nanoparticles with different particle sizes were synthesized and characterized by complementary characterization techniques such as X‐ray diffraction, N2 sorption, acetone temperature‐programmed desorption, transmission electron microscopy, and CO chemisorption. Using acetone steam reforming reaction as a probe reaction, we revealed a volcano‐shape curve of the intrinsic activity (turnover frequency of acetone) and the CO2 selectivity as a function of the cobalt particle size with the highest activity and selectivity observed at a particle size of approximately 12.8 nm. Our results indicate that the overall performance of acetone steam reforming is related to a combination of particle‐size‐dependent acetone decomposition, water dissociation, and the oxidation state of the cobalt nanoparticles.
Heterogeneous Catalyst of Mixed K Compounds/Ca‐Al‐Graphite Oxide for the Transesterification of Soybean Oil to Biodiesel
Authors: Sun Chuanjia , Qiu Fengxian , Yang Dongya , Ye Bin 
Published: June 2015

AbstractA novel heterogeneous solid base catalyst was prepared by loading of Ca‐Al‐graphite oxide with mixed potassium salts and applied in the transesterification of soybean oil with methanol to produce biodiesel. The catalysts were characterized by Hammett indicators, X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X‐ray spectrometry, and transmission electron microscopy. The effects of the methanol‐to‐oil molar ratio, catalyst amount, reaction temperature, stirring rate, and reaction time were investigated to optimize the transesterification reaction conditions. Moreover, the prepared catalyst retains its activity after being used for four cycles. In particular, the solid base catalyst can be effectively and easily separated from the reaction system, which may provide significant benefits for the development of an environmentally benign and continuous process for preparing biodiesel.
Design and Preparation of a Lithium‐rich Layered Oxide Cathode with a Mg‐Concentration‐Gradient Shell for Improved Rate Capability
Authors: Yu Ruizhi , Wang Gang , Wang Xianyou , Wang Di , Wen Weicheng , Shu Hongbo , Yang Xiukang 
Published: June 2015

AbstractA spherical core–shell lithium‐rich layered oxide material Li1.5Mn0.75Ni0.20Mg0.05O2+δ (CSLM) with a Mg‐concentration‐gradient shell is rationally designed and synthesized through a co‐precipitation method. The physicochemical and electrochemical properties of the CSLM cathode material are systematically investigated, and compared with the conventional Li1.5Mn0.75Ni0.25O2+δ (CL) cathode material. The electrochemical tests demonstrate that the CSLM cathode material exhibits better cycle stability and rate capability. The Li/CSLM cell delivers an excellent cycling performance with a capacity retention of 96.4 % after 100 cycles at 0.5 C. Moreover, at a high rate of 10 C, the Li/CSLM cell can still exhibit a high discharge capacity of 141.1 mAh g−1, as compared with 58.9 mAh g−1 for the Li/CL cell. Thus, lithium‐rich layered oxide material Li1.5Mn0.75Ni0.20Mg0.05O2+δ with a Mg‐concentration‐gradient shell is a promising cathode material for advanced lithium‐ion batteries.
The Structure and Conformation of (CH3)3CSNO
Authors: Canneva Antonela , Erben Mauricio F. , Romano Rosana M. , Vishnevskiy Yury V. , Reuter Christian G. , Mitzel Norbert W. , Della Védova Carlos O. 
Published: June 2015

AbstractThe gas‐phase molecular structure of (CH3)3CSNO was investigated by using electron diffraction, allowing the first experimental geometrical parameters for an S‐nitrosothiol species to be elucidated. Depending on the orientation of the SNO group, two conformers (anti and syn) are identified in the vapor of (CH3)3CSNO at room temperature, the syn conformer being less abundant. The conformational landscape is further scrutinized by using vibrational spectroscopy techniques, including gas‐phase and matrix‐isolation IR spectroscopy, resulting in a contribution of ca. 80:20 for the anti:syn abundance ratio, in good agreement with the computed value at the MP2(full)/cc‐pVTZ level of approximation. The UV/Vis and resonance Raman spectra also show the occurrence of the conformational equilibrium in the liquid phase, with a moderate post‐resonance Raman signature associated with the 350 nm electronic absorption.
A Tetraferrocenyl‐Resorcinarene Cavitand as a Redox‐Switchable Host of Ammonium Salts
Authors: Ruiz‐Botella Sheila , Vidossich Pietro , Ujaque Gregori , Vicent Cristian , Peris Eduardo 
Published: June 2015

AbstractTetraannulation of a resorcinarene‐octaamino cavitand with ferrocenecarboxaldehyde allows the preparation of a tetrabenzimidazole‐resorcinarene cavitand with four ferrocenyl moieties directly linked to the C2 atom of the imidazole units. Oxidation of the four ferrocenyl moieties produces important structural modifications of the molecule, as indicated by DFT calculations performed for the neutral and tetraoxidized forms of the cavitand. By means of 1H NMR spectroscopic analysis, the encapsulating properties of the new tetraferrocenyl‐resorcinarene cavitand toward a series of ammonium salts were evaluated, and a clear cutoff point in binding affinity with respect to size was observed. Cyclic voltammetric studies allowed us to estimate the relative association constants for the neutral and oxidized forms of the cavitand, thus indicating that the guest was bound to the neutral (reduced) state of the cavitand and was released from the oxidized form. These redox‐addressable conformational and binding properties of the resorcinarene‐tetraferrocenyl cavitand constitute all the necessary features of a redox‐switchable molecular gripper. By means of mass‐spectrometric analysis, we could unambiguously confirm the molar stoichiometry of the host–guest complex (1:1) and assess the strong guest encapsulation, as indicated by triggering the covalent coupling between host and guest in the gas phase.
Group 2 Catalysis for the Atom‐Efficient Synthesis of Imidazolidine and Thiazolidine Derivatives
Authors: Arrowsmith Merle , Hill Michael S. , Kociok‐Köhn Gabriele 
Published: June 2015

AbstractA wide variety of functionalised imidazolidine‐2‐ones and ‐thiones, 2‐imino‐imidazolidines and thiazolidine‐2‐thiones have been synthesised under very mild reaction conditions by using simple and cost‐effective alkaline earth bis(amide) precatalysts, [Ae{N(SiMe3)2}2(THF)2] (Ae=Mg, Ca, Sr). The reactions ensue with 100 % atom efficiency as one‐pot cascades from simple, commercially available terminal alkyne and heterocumulene reagents. The reactions take place through the initial assembly of propargylamidines, which are utilised in subsequent cyclisation reactions through addition of the isocyanate, isothiocyanate and, in one case, carbon disulfide reagents. This reactivity is deduced to take place through a well‐defined sequence of heterocumulene hydroacetylenation and alkyne hydroamidation steps, which are all mediated at the alkaline earth centre. The rate and regioselectivity of the cyclisation reactions are, thus, found to be heavily dependent upon the identity of the catalytic alkaline earth centre employed. Similarly, the selectivity of the reactions was observed to be profoundly affected by stereoelectronic variations in the individual substrates, albeit by a similar Group 2‐centred reaction mechanism in all cases studied.
Observation of Diastereomeric Interconversions of β‐Sulfinylsubporphyrins as Evidence for Bowl Inversion
Authors: Yoshida Kota , Osuka Atsuhiro 
Published: June 2015

AbstractB‐Methoxy β‐(4‐methoxyphenylsulfinyl)subporphyrin and B‐phenyl β‐(4‐methoxyphenylsulfinyl)subporphyrin were synthesized by oxidation of the corresponding β‐sulfanylsubporphyrins with m‐chloroperbenzoic acid and were separated into diastereomers, respectively. B‐Methoxy subporphyrin diastereomers were interconverted to each other in methanol or ethanol, whereas such interconversion was not observed for B‐phenyl subporphyrin diastereomers even at high temperature. Diastereomeric interconversions of B‐methoxy subporphyrins were dramatically accelerated by addition of trifluoroacetic acid. These results suggest that the diastereomeric interconversions of B‐methoxy subporphyrins, namely, their bowl inversions, proceed via a mechanism involving protonation‐induced generation of subporphyrin borenium cations followed by nucleophilic attacks by alcohols.
Chiral Iodine‐Catalyzed Dearomatizative Spirocyclization for the Enantioselective Construction of an All‐Carbon Stereogenic Center
Authors: Zhang Dong‐Yang , Xu Lue , Wu Hua , Gong Liu‐Zhu 
Published: June 2015

AbstractThe first enantioselective dearomatizative spirocyclization of 1‐hydroxy‐N‐aryl‐2‐naphthamide derivatives has been accomplished by chiral organoiodine catalysis to stereoselectively create an all‐carbon stereogenic center, providing a straightforward approach to access spirooxindole derivatives in good yields and with high to excellent levels of enantioselectivity. Chiral hypervalent phenyl‐λ3‐iodanes generated in situ from the oxidation of the chiral phenyl iodine actually participate in the asymmetric oxidative dearomatizative spirocyclization reaction.
Amide as Terminal Groups: Synthesis and Properties as New Tolane‐Type Liquid Crystals
Authors: Zhang Hong , Hong Fengying , Zhu Dezhao , Xia Zhengce , Wu Hongxiang , Wang Hui , Zeng Zhuo 
Published: June 2015

AbstractA series of novel tolane‐type liquid crystals with amide group as terminal group have been prepared. The terminal amide groups were modified, and the influence of these structural parameters on liquid crystal phases was investigated by polarizing optical microscope (POM) and differential scanning calorimetry (DSC). Three of these new compounds exhibit nematic phase, good thermal stabilities. In general, these liquid crystals with amide as end groups have high melting points and phase transition temperatures, which result from the hydrogen bonds. Based on theoretical calculations, these new molecules with strong electron donating amide as end group have narrower HOMO‐LUMO energy gap and higher dipole moment than tolane.
Epidermal growth factor receptor exon 20 insertions in advanced lung adenocarcinomas: Clinical outcomes and response to erlotinib
Authors: Naidoo Jarushka , Sima Camelia S. , Rodriguez Katherine , Busby Natalie , Nafa Khedoudja , Ladanyi Marc , Riely Gregory J. , Kris Mark G. , Arcila Maria E. , Yu Helena A. 
Published: June 2015

BACKGROUNDEpidermal growth factor receptor (EGFR) exon 20 insertions (exon20ins) represent approximately 10% of EGFR‐mutant lung adenocarcinomas, and are associated with resistance to EGFR tyrosine kinase inhibitors (TKIs). Clinical outcomes in comparison with patients with sensitizing EGFR mutations are not well established.METHODSPatients with stage IV lung adenocarcinomas with EGFR exon20ins were identified through routine molecular testing. Clinicopathologic data were collected. Overall survival (OS) was measured from the diagnosis of stage IV disease, and in patients treated with EGFR TKIs, the time to progression (TTP) on erlotinib was measured.RESULTSOne thousand eight hundred and eighty‐two patients with stage IV lung adenocarcinomas were identified: 46 patients had EGFR exon20ins (2%), and 258 patients had an EGFR exon 19 deletion (exon19del)/L858R point mutation (14%). Among 11 patients with lung adenocarcinomas with EGFR exon20ins who received erlotinib, 3 patients (27%) had a partial response (FQEA, 1; ASV, 1; and unknown variant, 1). TTP for patients with EGFR exon20ins and patients with EGFR exon19del/L858R on erlotinib were 3 and 12 months, respectively (P < .01). Responses to chemotherapy were similar for patients with lung adenocarcinomas with EGFR exon20ins and patients with lung adenocarcinomas with EGFR exon19del/L858R. Median OS from the diagnosis of stage IV disease for patients with EGFR exon20ins and patients with EGFR exon19del/L858R was 26 months (95% confidence interval, 19 months‐not reached n = 46) and 31 months (95% confidence interval, 28‐33 months; n = 258), respectively (P = .53).CONCLUSIONSThe majority of patients with advanced lung adenocarcinomas harboring EGFR exon20ins do not respond to EGFR TKI therapy. Standard chemotherapy should be used as first‐line therapy. These patients have an OS similar to that of patients with sensitizing EGFR mutations. Individuals with certain variants such as FQEA and ASV may respond to erlotinib. Cancer 2015;121:3212–3220. © 2015 American Cancer Society.