bluuebunny/crossref_metadata_2025_split huggingface dataset:
Histone proteolysis: A proposal for categorization into ‘clipping’ and ‘degradation’
Authors: Dhaenens Maarten , Glibert Pieter , Meert Paulien , Vossaert Liesbeth , Deforce Dieter 
Published: October 2014

We propose for the first time to divide histone proteolysis into “histone degradation” and the epigenetically connoted “histone clipping”. Our initial observation is that these two different classes are very hard to distinguish both experimentally and biologically, because they can both be mediated by the same enzymes. Since the first report decades ago, proteolysis has been found in a broad spectrum of eukaryotic organisms. However, the authors often not clearly distinguish or determine whether degradation or clipping was studied. Given the importance of histone modifications in epigenetic regulation we further elaborate on the different ways in which histone proteolysis could play a role in epigenetics. Finally, unanticipated histone proteolysis has probably left a mark on many studies of histones in the past. In conclusion, we emphasize the significance of reviving the study of histone proteolysis both from a biological and an experimental perspective.Also watch the Video Abstract.
Development of a cataluminescence sensor for detecting benzene based on magnesium silicate hollow spheres
Authors: Wang Yuhuai , Li Bo , Wang Qihui , Shou Zhouxiang 
Published: October 2014

AbstractA novel and sensitive gas sensor was developed for the determination of benzene based on its cataluminescence (CTL) by oxidation in air on the surface of hollow magnesium silicate spheres. Luminescence characteristics and optimum conditions were investigated. Results indicated that the as‐prepared magnesium silicate hollow spheres exhibited outstanding CTL properties such as stable intensity, high signal/noise values, and short response and recovery times. Under optimized conditions, benzene exhibited a broad linear range of 1–4500 ppm, with a correlation coefficient of 0.9946 and a limit of detection (signal‐to‐noise ratio (S/N) = 3) of 0.6 ppm, which was below the standard permitted concentration. The relative standard deviation (RSD) for 100 ppm benzene was 4.3% (n = 6). Furthermore, the gas sensor system showed outstanding selectivity for benzene compared with nine other common volatile organic compounds (VOCs). The proposed gas sensor showed good characteristics of high selectivity, fast response time and long lifetime, which suggested the promising application of magnesium silicate hollow spheres as a novel highly efficient CTL sensing material. The mechanism for the improved performance was also discussed based on the experimental results. Copyright © 2014 John Wiley & Sons, Ltd.
Expanding frontiers in plant transcriptomics in aid of functional genomics and molecular breeding
Authors: Agarwal Pinky , Parida Swarup K. , Mahto Arunima , Das Sweta , Mathew Iny Elizebeth , Malik Naveen , Tyagi Akhilesh K. 
Published: October 2014

AbstractThe transcript pool of a plant part, under any given condition, is a collection of mRNAs that will pave the way for a biochemical reaction of the plant to stimuli. Over the past decades, transcriptome study has advanced from Northern blotting to RNA sequencing (RNA‐seq), through other techniques, of which real‐time quantitative polymerase chain reaction (PCR) and microarray are the most significant ones. The questions being addressed by such studies have also matured from a solitary process to expression atlas and marker‐assisted genetic enhancement. Not only genes and their networks involved in various developmental processes of plant parts have been elucidated, but also stress tolerant genes have been highlighted. The transcriptome of a plant with altered expression of a target gene has given information about the downstream genes. Marker information has been used for breeding improved varieties. Fortunately, the data generated by transcriptome analysis has been made freely available for ample utilization and comparison. The review discusses this wide variety of transcriptome data being generated in plants, which includes developmental stages, abiotic and biotic stress, effect of altered gene expression, as well as comparative transcriptomics, with a special emphasis on microarray and RNA‐seq. Such data can be used to determine the regulatory gene networks, which can subsequently be utilized for generating improved plant varieties.
Value of CT–PET after neoadjuvant chemoradiation in the prediction of histological tumour regression, nodal status and survival in oesophageal adenocarcinoma
Authors: Elliott J A , O'Farrell N J , King S , Halpenny D , Malik V , Muldoon C , Johnston C , Reynolds J V 
Published: October 2014

Abstract

Background
The role of CT–PET after neoadjuvant chemoradiation (nCRT) for prediction of pathological response and oncological outcome in oesophageal and junctional adenocarcinoma (OAC) is unclear. The relationship between complete metabolic response (cMR), pathological complete response (pCR) and nodal status has not been clarified.

Methods
Patients with locally advanced OAC selected to receive nCRT and surgery with curative intent, on the basis of staging that included CT–PET positivity, were included. Repeat scanning (PET2) with an identical protocol was performed 2–4 weeks after completion of nCRT (cisplatin and 5-fluorouracil plus 44 Gy radiation). Changes in [18F]fluorodeoxyglucose uptake, considered as either a maximum standardized uptake value (SUVmax) or a relative reduction (%ΔSUVmax), and PET-predicted nodal status following nCRT were compared with histopathological response, histological node positivity and survival.

Results
One hundred consecutive patients with PET-positive OAC were studied. Following nCRT, PET2 identified M1 disease in 2·0 per cent of patients. There were no significant associations between PET2 SUVmax or %ΔSUVmax with respect to primary tumour stage (ypT) (P = 0.216 and P = 0·975 respectively), tumour regression grade (P = 0·109 and P = 0·232), pCR (P = 0·633 and P = 0·870) or complete resection (R0) (P = 0·440 and P = 0·235). The sensitivity of PET2 for ypN was 10 per cent. %ΔSUVmax was not associated with disease-free or overall survival (P = 0·162 and P = 0·154 respectively). Of 46 patients with a cMR on PET2, 37 (80 per cent) had histological evidence of residual tumour in the resected specimen, and cMR was not associated with overall survival benefit (P = 0·478).

Conclusion
CT–PET following nCRT for OAC has poor prognostic and discriminatory value for clinical application.
Effect of neoadjuvant chemotherapy on resectability of stage III and IV hepatoblastoma
Authors: Venkatramani R , Stein J E , Sapra A , Genyk Y , Jhaveri V , Malogolowkin M , Mascarenhas L 
Published: October 2014

Abstract

Background
The potential for surgical resection of primary hepatoblastoma tumours was assessed at diagnosis, and after two and four cycles of neoadjuvant chemotherapy.

Methods
Available radiographic images for patients with stage III and IV hepatoblastoma diagnosed between 1991 and 2008 were reviewed. The extent of disease was determined at diagnosis using the PRETEXT staging system, and after two and four cycles of therapy by POST-TEXT staging. Tumour resectability based on radiographic studies was assessed independently by two surgeons with expertise in hepatic surgery who were blinded to treatment and clinical outcome.

Results
Radiographic images from 20 patients with hepatoblastoma were reviewed. Six of 20 tumours were downstaged after two cycles, and three additional tumours were downstaged following four cycles. All PRETEXT stage III and IV tumours were determined to be surgically unresectable at diagnosis. The number of tumours considered unresectable decreased from 16 of 20 at diagnosis to seven of 20 after two cycles, and to four of 20 after four cycles. Five of the seven tumours that were unresectable after two cycles, and all four tumours that were unresectable after four cycles would have qualified for liver transplant based on radiographic studies.

Conclusion
The majority of stage III and IV hepatoblastomas achieved radiographic resectability after two cycles of chemotherapy. There may be an opportunity for earlier surgical intervention and potential for a reduction in chemotherapy in a considerable number of patients.
Electropolymerized Polypyrrole Nanocoatings on Carbon Paper for Electrochemical Energy Storage
Authors: Wei Huige , Wang Yiran , Guo Jiang , Yan Xingru , O'Connor Ryan , Zhang Xin , Shen Nancy Z. , Weeks Brandon L. , Huang Xiaohua , Wei Suying , Guo Zhanhu 
Published: October 2014

AbstractA highly electrically conductive and uniform polymer film containing small, evenly sized particles was potentiodynamically electropolymerized at a slow scan rate of 50 mV s−1, as compared to the strongly agglomerated and low‐conducting films obtained at higher scan rates of 100 and 200 mV s−1. Cyclic voltammetry and galvanostatic charge–discharge experiments demonstrated a higher areal capacitance, energy density, and power density in the former material. The superior supercapacitive performance was studied by electrochemical impedance spectroscopy (EIS) and can be explained by both a higher electrical conductivity and a facilitated charge transfer in the redox reactions occurring in the former electrode. This work suggests the possibility of fabricating polypyrrole (PPy) pseudocapactive electrodes with high performance via a facile potentiodynamic synthesis at low scan rates. Meanwhile, it provides an alternative to introducing surface functionalities of conductive polymers onto the carbon paper.
Synthesis of Highly Substituted γ‐Butyrolactones by a Gold‐Catalyzed Cascade Reaction of Benzyl Esters
Authors: Blanco Jaimes Maria Camila , Ahrens Alexander , Pflästerer Daniel , Rudolph Matthias , Hashmi A. Stephen K. 
Published: October 2014

AbstractEasily accessible benzylic esters of 3‐butynoic acids in a gold‐catalyzed cyclization/rearrangement cascade reaction provided 3‐propargyl γ‐butyrolactones with the alkene and the carbonyl group not being conjugated. Crossover experiments showed that the formation of the new CC bond is an intermolecular process. Initially propargylic–benzylic esters were used, but alkyl‐substituted benzylic esters worked equally well. In the case of the propargylic–benzylic products, a simple treatment of the products with aluminum oxide initiated a twofold tautomerization to the allenyl‐substituted γ‐butyrolactones with conjugation of the carbonyl group, the olefin, and the allene. The synthetic sequence can be conducted stepwise or as a one‐pot cascade reaction with similar yields. Even in the presence of the gold catalyst the new allene remains intact.
Supermolecular Columnar Liquid‐Crystalline Phosphorus Dendrimers Decorated with Sulfonamide Derivatives
Authors: Hincapié Cesar Augusto , Sebastián Rosa María , Barberá Joaquín , Serrano José Luis , Sierra Teresa , Majoral Jean‐Pierre , Caminade Anne‐Marie 
Published: October 2014

AbstractA series of supermolecular liquid crystals has been synthesized by combining phosphorus dendrimers of the zero, first, and fourth generations with sulfonamide derivatives, thus generating dendromesogens bearing 6, 12, and 96 mesogenic units on their surfaces. The relevant reactions could be monitored by 1H, 19F, and 31P{1H} NMR spectroscopies. The thermal and mesomorphic properties of the products have been studied by optical microscopy, differential scanning calorimetry, and X‐ray diffraction. All of the new macromolecules prepared in this work have been found to show mesomorphic properties over a wide temperature range; moreover, for all of the compounds, the columnar mesophases observed were maintained or vitrified at room temperature. On increasing the generation of these dendromesogens, mesophases appear at lower temperatures and remain stable over a wider temperature interval. In all cases, on the basis of X‐ray analysis, a cylindrical symmetry of the molecules can be proposed to promote the supramolecular columnar arrangement observed in the mesophases. In this type of model, the height of the dendrimer clearly increases with increasing dendrimer generation, whereas its cross‐ sectional area increases only slightly, probably due to compression of the highly hyperbranched structures as a consequence of their progressive steric constraints. The mesomorphic arrangement is governed by the peripheral sulfonamide units.
Geminally Diaurated Aryls Bridged by Semirigid Phosphine Pillars: Syntheses and Electronic Structure
Authors: Browne Amberle R. , Deligonul Nihal , Anderson Bryce L. , Rheingold Arnold L. , Gray Thomas G. 
Published: October 2014

AbstractGeminally diaurated μ2‐aryl complexes have been prepared where gold(I) centers were bridged by the semirigid diphosphine ligands bis(2‐diphenylphosphinophenyl)ether (DPEphos) and 4,6‐bis(diphenylphosphanyl)dibenzo[b,d]furan (DBFphos). Diaurated complexes were synthesized in ligand redistribution reactions of the corresponding di‐gold dichlorides with di‐gold diaryls (six of them new) and silver(I) salts. Diaurated complexes were isolated as salts of the minimally coordinating anions SbF6− and ReO4−. Efforts to prepare salts of the tetraarylborate [B(3,5‐(CF3)2C6H3)4]− led to transmetalation from boron, with crystallization of the fluorinated aryl complex. The new complexes were characterized by multinuclear NMR, absorption and emission spectroscopies, 77 K emission lifetimes, and by combustion analysis; three are crystallographically characterized. Structures of geminally diaurated aryl ligands are compared to those of mono‐aurated analogues. Both crystal structures and density‐functional theory calculations indicate slight but observable disruptions of aryl ligand aromaticity by geminal di‐gold binding. An intermolecular aurophilic interaction in one structurally authenticated complex was examined computationally.
Distribution of Butane in the Host Water Cage of Structure II Clathrate Hydrates
Authors: Takeya Satoshi , Fujihisa Hiroshi , Hachikubo Akihiro , Sakagami Hirotoshi , Gotoh Yoshito 
Published: October 2014

AbstractTo understand host–guest interactions of hydrocarbon clathrate hydrates, we investigated the crystal structure of simple and binary clathrate hydrates including butane (n‐C4H10 or iso‐C4H10) as the guest. Powder X‐ray diffraction (PXRD) analysis using the information on the conformation of C4H10 molecules obtained by molecular dynamics (MD) simulations was performed. It was shown that the guest n‐C4H10 molecule tends to change to the gauche conformation within host water cages. Any distortion of the large 51264 cage and empty 512 cage for the simple iso‐C4H10 hydrate was not detected, and it was revealed that dynamic disorder of iso‐C4H10 and gauche‐nC4H10 were spherically extended within the large 51264 cages. It was indicated that structural isomers of hydrocarbon molecules with different van der Waals diameters are enclathrated within water cages in the same way owing to conformational change and dynamic disorder of the molecules. Furthermore, these results show that the method reported herein is applicable to structure analysis of other host–guest materials including guest molecules that could change molecular conformations.
Mechanistic Study of the Titanocene(III)‐Catalyzed Radical Arylation of Epoxides
Authors: Gansäuer Andreas , von Laufenberg Daniel , Kube Christian , Dahmen Tobias , Michelmann Antonius , Behlendorf Maike , Sure Rebecca , Seddiqzai Meriam , Grimme Stefan , Sadasivam Dhandapani V. , Fianu Godfred D. , Flowers II Robert A. 
Published: October 2014

AbstractAn atom‐economical and catalytic arylation of epoxide‐derived radicals is described. The key step of the catalytic system is a sequential electron and proton transfer for the rearomatization of the radical σ‐complex and catalyst regeneration. Kinetic, computational, spectroscopic, and cyclovoltammetric investigations highlight the key issues of the reaction mechanism and catalyst stabilization by collidine hydrochloride. Studies employing radicophiles rule out the participation of cations as reactive intermediates.
Absolute Asymmetric Synthesis in Enantioselective Autocatalytic Reaction Networks: Theoretical Games, Speculations on Chemical Evolution and Perhaps a Synthetic Option
Authors: Ribó Josep M. , Blanco Celia , Crusats Joaquim , El‐Hachemi Zoubir , Hochberg David , Moyano Albert 
Published: October 2014

AbstractThe Soai reaction and the Viedma deracemization of racemic conglomerate crystal mixtures are experimental pieces of evidence of the ability of enantioselective autocatalytic coupled networks to yield absolute asymmetric synthesis. Thermodynamically open systems or systems with non‐uniform energy distributions may lead to chiral final states and, in systems able to come into thermodynamic equilibrium with their surroundings, to kinetically controlled absolute asymmetric synthesis. The understanding of network parameters and of the thermodynamic scenarios that may lead to spontaneous mirror symmetry breaking (SMSB) could assist in the development of new methods for asymmetric synthesis and enantioselective polymerizations (e.g., replicators), and to frame reasonable speculations on the origin of biological homochirality.
MnO2‐Modified Persistent Luminescence Nanoparticles for Detection and Imaging of Glutathione in Living Cells and In Vivo
Authors: Li Na , Diao Wei , Han Yaoyao , Pan Wei , Zhang Tingting , Tang Bo 
Published: October 2014

AbstractPersistent luminescence nanoparticles (PLNPs) hold great promise for the detection and imaging of biomolecules. Herein, we have demonstrated a novel nanoprobe, based on the manganese dioxide (MnO2)‐modified PLNPs, that can detect and image glutathione in living cells and in vivo. The persistent luminescence of the PLNPs can be efficiently quenched by the MnO2 nanosheets. In the presence of glutathione (GSH), MnO2 was reduced to Mn2+ and the luminescence of PLNPs can be restored. The persistent luminescence property can allow detection and imaging without external excitation and avoid the background noise originating from the in situ excitation. This strategy can offer a promising platform for detection and imaging of reactive species in living cells or in vivo.
Alkylation of Pyridines at Their 4‐Positions with Styrenes plus Yttrium Reagent or Benzyl Grignard Reagents
Authors: Mizumori Tomoya , Hata Takeshi , Urabe Hirokazu 
Published: October 2014

AbstractA new regioselective alkylation of pyridines at their 4‐position was achieved with styrenes in the presence of yttrium trichloride, BuLi, and diisobutylaluminium hydride (DIBAL‐H) in THF. Alternatively, similar products were more simply prepared from pyridines and benzyl Grignard reagents. These reactions are not only a useful preparation of 4‐substituted pyridines but are also complementary to other relevant reactions usually giving 2‐substituted pyridines.
Low‐Temperature Topochemical Transformation of Bi13Pt3I7 into the New Layered Honeycomb Metal Bi12Pt3I5
Authors: Kaiser Martin , Rasche Bertold , Isaeva Anna , Ruck Michael 
Published: October 2014

AbstractOrdered single‐crystals of the metallic subiodide Bi13Pt3I7 were grown and treated with n‐butyllithium. At 45 °C, complete pseudomorphosis to Bi12Pt3I5 was achieved within two days. The new compound is air‐stable and contains the same ${{{\hfill 2\atop \hfill \infty }}}$[(PtBi8/2)3I]n+ honeycomb nets and iodide layers as the starting material Bi13Pt3I7, but does not include ${{{\hfill 1\atop \hfill \infty }}}$[BiI2I4/2]− iodidobismuthate strands. Electron microscopy and X‐ray diffraction studies of solid intermediates visualize the process of the topochemical crystal‐to‐crystal transformation. In the electronic band structures of Bi13Pt3I7 and Bi12Pt3I5, the vicinities of the Fermi levels are dominated by the intermetallic fragments. Upon the transformation of Bi13Pt3I7 into Bi12Pt3I5, the intermetallic part is oxidized and the Fermi level is lowered by 0.16 eV. Whereas in Bi13Pt3I7 the intermetallic layers do not interact across the iodidobismuthate spacers (two‐dimensional metal), they couple in Bi12Pt3I5 and form a three‐dimensional metal.
Fourfold Diels–Alder Reaction of Tetraethynylsilane
Authors: Geyer Florian L. , Rode Alexander , Bunz Uwe H. F. 
Published: October 2014

AbstractA series of ethynylated silanes, including tetraethynylsilane, was treated with tetraphenylcyclopentadienone at 300 °C under microwave irradiation to give the aromatized Diels–Alder adducts as sterically encumbered mini‐dendrimers with up to 20 benzene rings. The sterically most congested adducts display red‐shifted emission through intramolecular π–π interactions in the excited state.
Metallogels Derived from Silver Coordination Polymers of C3‐Symmetric Tris(pyridylamide) Tripodal Ligands: Synthesis of Ag Nanoparticles and Catalysis
Authors: Paul Mithun , Sarkar Koushik , Dastidar Parthasarathi 
Published: October 2014

AbstractBy applying a recently developed crystal engineering rationale, four C3 symmetric tris(pyridylamide) ligands namely 1,3,5‐tris(nicotinamidomethyl)‐2,4,6‐triethylbenzene, 1,3,5‐tris(isonicotinamidomethyl)‐2,4,6‐triethylbenzene, 1,3,5‐tris(nicotinamidomethyl)‐2,4,6‐trimethylbenzene, and 1,3,5‐tris(isonicotinamidomethyl)‐2,4,6‐trimethylbenzene, which contain potential hydrogen‐bonding sites, were designed and synthesized for generating AgI coordination polymers and coordination‐polymer‐based gels. The coordination polymers thus obtained were characterized by single‐crystal X‐ray diffraction. The silver metallogels were characterized by transmission electron microscopy (TEM) and dynamic rheology. Upon exposure to visible light, these silver metallogels produced silver nanoparticles (AgNPs), which were characterized by TEM, powder X‐ray diffraction, energy dispersive X‐ray and X‐ray photoelectron spectroscopy. These NPs were found to be effectively catalyzed the reduction of 4‐nitrophenolate to 4‐aminophenolate without the use of any exogenous reducing agent.
Cyclodextrin‐Based Size‐Complementary [3]Rotaxanes: Selective Synthesis and Specific Dissociation
Authors: Akae Yosuke , Koyama Yasuhito , Kuwata Shigeki , Takata Toshikazu 
Published: October 2014

Abstractα‐Cyclodextrin (CD)‐based size‐complementary [3]rotaxanes with alkylene axles were prepared in one‐pot by end‐capping reactions with aryl isocyanates in water. The selective formation of [3]rotaxane with a head‐to‐head regularity was indicated by the X‐ray structural analyses. Thermal degradation of the [3]rotaxanes bearing appropriate end groups proceeded by stepwise dissociation to yield not only the original components but also [2]rotaxanes. From the kinetic profiles of the deslippage, it turned out that the maximum yield of [2]rotaxane was estimated to be 94 %. Thermodynamic studies and NOESY analyses of such rotaxanes revealed that [2]rotaxanes are specially stabilized, and that the dissociation capability of the [3]rotaxanes to the components can be adjusted by controlling the structure of the end groups, direction of the CD groups, and length of the alkylene axle.