bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tetrapeptidic Molecular Hydrogels: Self‐assembly and Co‐aggregation with Amyloid Fragment Aβ1‐40
Authors: Tena‐Solsona Marta , Miravet Juan F. , Escuder Beatriu 
Published: December 2013

AbstractA new family of isomeric tetrapeptides containing aromatic and polar amino acid residues that are able to form molecular hydrogels following a smooth change in pH is described. The hydrogels have been studied by spectroscopic and microscopic techniques showing that the peptide primary sequence has an enormous influence on the self‐assembly process. In particular, the formation of extended hydrophobic regions and the appearance of π‐stacking interactions have been revealed as the driving forces for aggregation. Moreover, the interaction of these compounds with amyloid peptidic fragment Aβ1‐40 has been studied and some of them have been shown to act as templates for the aggregation of this peptide into non‐β‐sheet fibrillar structures. These compounds could potentially be used for the capture of toxic, soluble amyloid oligomers.
A New Class of Dendritic Metallogels with Multiple Stimuli‐Responsiveness and as Templates for the In Situ Synthesis of Silver Nanoparticles
Authors: Liu Zhi‐Xiong , Feng Yu , Zhao Zhi‐Yong , Yan Zhi‐Chao , He Yan‐Mei , Luo Xu‐Jun , Liu Chen‐Yang , Fan Qing‐Hua 
Published: December 2013

AbstractA new class of poly(aryl ether) dendritic ligands containing a pyridine functionality at the focal point and the corresponding AgI complexes through metal–ligand coordination were designed, synthesized, and fully characterized. Compared with the dendritic ligands, the corresponding dendritic complexes exhibited much better gelation ability for various organic solvents at very low critical gelation concentrations. The gel–sol phase transition temperatures and morphologies could be finely tuned by binding silver ion to the ligand. A preliminary study revealed that multiple noncovalent interactions, such as AgI–pyridine coordination, solvophobic interaction, and π–π stacking, synergistically enable the formation of stable metallogels. Interestingly, these metallogels could intelligently respond to multiple external stimuli including temperature, chemicals, and shear stress, leading to gel–sol phase transitions. In addition, these dendritic metallogels were successfully applied as templates for the in situ formation and stabilization of silver nanoparticles without the use of any chemical reducing/stabilizing agents.
Pyrene‐Based Fluorescent Ambidextrous Gelators: Scaffolds for Mechanically Robust SWNT–Gel Nanocomposites
Authors: Mandal Deep , Kar Tanmoy , Das Prasanta Kumar 
Published: December 2013

AbstractWith the rapid progress in the development of supramolecular soft materials, examples of low‐molecular‐weight gelators (LMWGs) with the ability to immobilise both water and organic solvents by the same structural scaffold are very limited. In this paper, we report the development of pyrene‐containing peptide‐based ambidextrous gelators (AGs) with the ability to efficiently gelate both organic and aqueous solvents. The organo‐ and hydrogelation efficiencies of these gelators are in the range 0.7–1.1 % w/v in various organic solvents and 0.5–5 % w/v in water at certain acidic pH values (pH 2.0–4.0). Moreover, for the first time, AGs have been utilised to prepare single‐walled carbon‐nanotube (SWNT)‐included soft nanocomposites in both hydro‐ and organogel matrices. The influence of different non‐covalent interactions such as hydrogen bonding, hydrophobic, π–π and van der Waals interactions in self‐assembled gelation has been studied in detail by circular dichroism, FTIR, variable‐temperature NMR, 2D NOESY and luminescence spectroscopy. Interestingly, the presence of the pyrene moiety in the structure rendered these AGs intrinsically fluorescent, which was quenched upon successful integration of the SWNTs within the gel. The prepared hydro‐ and organogels along with their SWNT‐integrated nanocomposites are thermoreversible in nature. The supramolecular morphologies of the dried gels and SWNT–gel nanocomposites have been studied by transmission electron microscopy, fluorescence microscopy and polarising optical microscopy, which confirmed the presence of three‐dimensional self‐assembled fibrillar networks (SAFINs) as well as the integrated SWNTs. Importantly, rheological studies revealed that the inclusion of SWNTs within the ambidextrous gels improved the mechanical rigidity of the resulting soft nanocomposites up to 3.8‐fold relative to the native gels.
Towards Design Rules for Covalent Nanostructures on Metal Surfaces
Authors: Björk Jonas , Hanke Felix 
Published: December 2013

AbstractThe covalent molecular assembly on metal surfaces is explored, outlining the different types of applicable reactions. Density functional calculations for on‐surface reactions are shown to yield valuable insights into specific reaction mechanisms and trends across the periodic table. Finally, it is shown how design rules could be derived for nanostructures on metal surfaces.
Enhancing the Electrochemical Performance of the LiMn2O4 Hollow Microsphere Cathode with a LiNi0.5Mn1.5O4 Coated Layer
Authors: Liu Wei , Liu Jun , Chen Kunfeng , Ji Shaomin , Wan Yanling , Zhou Yichun , Xue Dongfeng , Hodgson Peter , Li Yuncang 
Published: December 2013

AbstractSpinel cathode materials consisting of LiMn2O4@LiNi0.5Mn1.5O4 hollow microspheres have been synthesized by a facile solution‐phase coating and subsequent solid‐phase lithiation route in an atmosphere of air. When used as the cathode of lithium‐ion batteries, the double‐shell LiMn2O4@LiNi0.5Mn1.5O4 hollow microspheres thus obtained show a high specific capacity of 120 mA h g−1 at 1 C rate, and excellent rate capability (90 mAhg−1 at 10 C) over the range of 3.5–5 V versus Li/Li+ with a retention of 95 % over 500 cycles.
PPh3⋅HBr‐DMSO Mediated Expedient Synthesis of γ‐Substituted β,γ‐Unsaturated α‐Ketomethylthioesters and α‐Bromo Enals: Application to the Synthesis of 2‐Methylsulfanyl‐3(2 H)‐furanones
Authors: Mal Kanchan , Sharma Abhinandan , Maulik Prakas R. , Das Indrajit 
Published: December 2013

AbstractAn efficient chemoselective general procedure for the synthesis of γ‐substituted β,γ‐unsaturated α‐ketomethylthioesters from α,β‐unsaturated ketones has been achieved through an unprecedented PPh3⋅HBr‐DMSO mediated oxidative bromination and Kornblum oxidation sequence. The newly developed reagent system serves admirably for the synthesis of α‐bromoenals from enals. Furthermore, AuCl3‐catalyzed efficient access to 3(2H)‐furanones from the above intermediates under extremely mild conditions are described.
Strong Intermolecular Exciton Couplings in Solid‐State Circular Dichroism of Aryl Benzyl Sulfoxides
Authors: Padula Daniele , Pietro Sebastiano Di , Capozzi Maria Annunziata M. , Cardellicchio Cosimo , Pescitelli Gennaro 
Published: December 2013

ABSTRACTA series of 13 enantiopure aryl benzyl sulfoxides (1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1i, 1j, 1k, 1l, 1m) with different substituents on the two aromatic rings has been previously analyzed by means of electronic circular dichroism (CD) spectroscopy. Most of these compounds are crystalline and their X‐ray structure is established. For almost one‐half of the series, CD spectra measured in the solid state were quite different from those in acetonitrile solution. We demonstrate that the difference is due to strong exciton couplings between molecules packed closely together in the crystal. The computational approach consists of time‐dependent density functional theory (TDDFT) calculations run on “dimers” composed of nearest neighbors found in the lattice. Solid‐state CD spectra are well reproduced by the average of all possible pairwise terms. The relation between the crystal space group and conformation, and the appearance of solid‐state CD spectra, is also discussed. Chirality 26:462–470, 2013. © 2013 Wiley Periodicals, Inc.
Adsorptive Pretreatment of Crude Glycerol Prior to Fermentation to 1,3‐Propanediole by Clostridium Diolis
Authors: Wiesen Sebastian , Tippkötter Nils , Muffler Kai , Suck Kirstin , Sohling Ulrich , Ruf Nils , Ulber Roland 
Published: December 2013

AbstractBei der Gewinnung von Fettsäuren aus Pflanzenölen, z. B. zur Herstellung von Biopolymeren, oder bei der Biodiesel‐ und Seifenproduktion, fällt Glycerin als Nebenprodukt an. Bei der Biokonversion dieses Rohstoffes zu 1,3‐Propandiol wird der Produktionsorganismus Clostridium diolis durch Verunreinigungen im Rohglycerin gehemmt. Als inhibierende Substanzen konnten freie Fettsäuren identifiziert werden. Mithilfe eines adsorptiven Aufarbeitungsverfahrens ist es gelungen, die Fettsäuren zu entfernen und die Konversionseffizienz zu 1,3‐Propandiol zu erhöhen.
A One‐pot Approach to Ethyl 1,4,5‐Triaryl‐1H‐pyrazole‐3‐carboxylates via an Improved Claisen Condensation‐Knorr Reaction Sequence
Authors: Zhai Jiaojiao , Gu Chunhui , Jiang Jianan , Zhang Shunli , Liao Daohua , Wang Lei , Zhu Dunru , Ji Yafei 
Published: December 2013

AbstractA one‐pot approach to ethyl 1,4,5‐triaryl‐1H‐pyrazole‐3‐carboxylates has been developed in moderate to high yields. The tert‐BuOLi‐mediated Claisen condensation of 1,2‐diarylethanones and ethyl oxalyl chloride efficiently provided the enolized lithium salts of ethyl 2,4‐dioxo‐3,4‐diarylbutanoates, which in situ reacted with arylhydrazine hydrochlorides via a hydrochloric acid‐promoted Knorr reaction to produce the exquisite triarylpyrazole‐3‐carboxylates. The procedure promises a convenient access to this highly crowded framework for drug discovery.
Resistant Hypertension Optimal Treatment Trial: A Randomized Controlled Trial
Authors:   The ReHOT Investigators
Published: December 2013

AbstractThe prevalence of resistant hypertension (ReHy) is not well established. Furthermore, diuretics, angiotensin‐converting enzyme inhibitors or angiotensin‐receptor blockers, and calcium channel blockers are largely used as the first 3‐drug combinations for treating ReHy. However, the fourth drug to be added to the triple regimen is still controversial and guided by empirical choices. We sought (1) to determine the prevalence of ReHy in patients with stage II hypertension; (2) to compare the effects of spironolactone vs clonidine, when added to the triple regimen; and (3) to evaluate the role of measuring sympathetic and renin‐angiotensin‐aldosterone activities in predicting blood pressure response to spironolactone or clonidine. The Resistant Hypertension Optimal Treatment (ReHOT) study (ClinicalTrials.gov NCT01643434) is a prospective, multicenter, randomized trial comprising 26 sites in Brazil. In step 1, 2000 patients will be treated according to hypertension guidelines for 12 weeks, to detect the prevalence of ReHy. Medical therapy adherence will be checked by pill count monitoring. In step 2, patients with confirmed ReHy will be randomized to an open label 3‐month treatment with spironolactone (titrating dose, 12.5–50 mg once daily) or clonidine (titrating dose, 0.1–0.3 mg twice daily). The primary endpoint is the effective control of blood pressure after a 12‐week randomized period of treatment. The ReHOT study will disseminate results about the prevalence of ReHy in stage II hypertension and the comparison of spironolactone vs clonidine for blood pressure control in patients with ReHy under 3‐drug standard regimen.
An open‐label, single‐arm, phase 2 trial of the polo‐like kinase inhibitor volasertib (BI 6727) in patients with locally advanced or metastatic urothelial cancer
Authors: Stadler Walter M. , Vaughn David J. , Sonpavde Guru , Vogelzang Nicholas J. , Tagawa Scott T. , Petrylak Daniel P. , Rosen Peter , Lin Chia‐Chi , Mahoney John , Modi Sanjiv , Lee Peter , Ernstoff Marc S. , Su Wu‐Chou , Spira Alexander , Pilz Korinna , Vinisko Richard , Schloss Charles , Fritsch Holger , Zhao Charles , Carducci Michael A. 
Published: December 2013

BACKGROUNDPolo‐like kinases (Plks) control multiple steps during the cell cycle, and Plk1 is overexpressed in urothelial cancer (UC). Volasertib (BI 6727), a Plk inhibitor, has demonstrated antitumor activity in several malignancies, including UC. In this phase 2 trial, the authors investigated volasertib as a second‐line treatment in advanced/metastatic UC.METHODSPatients who progressed within 2 years of 1 prior chemotherapy regimen received 300 mg volasertib on day 1 every 3 weeks. The dose was escalated to 350 mg in cycle 2 if volasertib was tolerated in cycle 1. The primary endpoint was tumor response, which was assessed every 6 weeks; secondary endpoints were progression‐free survival, overall survival, duration of response, safety, and pharmacokinetics.RESULTSFifty patients were enrolled, and the median patient age was 68.5 years (range, 52‐83 years). All patients had received prior platinum, 94% of patients had relapsed ≤2 years after prior therapy, 36% had liver metastases, and 54% had lung metastases. The median number of treatment cycles was 2 (range, 1‐27 treatment cycles), and 23 patients were dose escalated at cycle 2. Seven patients (14%) had a partial response, 13 (26%) had stable disease, and 30 (60%) progressed within 6 weeks. The median response duration was 41 weeks (range, 29.1‐77.3 weeks). The median progression‐free survival was 1.4 months, and the median overall survival was 8.5 months. The most frequent grade 3 and 4 adverse events were neutropenia (28%), thrombocytopenia (20%), and anemia (16%). No cumulative toxicity was observed.CONCLUSIONSVolasertib as second‐line treatment for advanced/metastatic UC had an acceptable safety profile but demonstrated insufficient antitumor activity for further evaluation as a monotherapy. Cancer 2014;120:976–982. © 2013 American Cancer Society.
Cervista HPV assays for fine‐needle aspiration specimens are a valid option for human papillomavirus testing in patients with oropharyngeal carcinoma
Authors: Guo Ming , Khanna Abha , Dhillon Jasreman , Patel Shobha J. , Feng Jie , Williams Michelle D. , Bell Diana M. , Gong Yun , Katz Ruth L. , Sturgis Erich M. , Staerkel Gregg A. 
Published: December 2013

BACKGROUNDThe objectives of this study were to evaluate the validity of Cervista human papillomavirus (HPV) assays in head and neck fine‐needle aspiration (FNA) specimens from patients with head and neck squamous carcinomas and to verify that the Cervista assay in FNA specimens is a valid option for determining HPV status in patients with oropharyngeal carcinomas.METHODSThe authors retrospectively retrieved 64 head and neck FNA specimens from patients who had head and neck squamous carcinoma. The specimens were tested for HPV types 16 and 18 (HPV16/18) and for high‐risk (HR) HPV DNA using the Cervista HPV16/18 and HPV HR assays, respectively. The results from those assays were compared with the results from polymerase chain reaction (PCR)‐based HPV assays in the same tissues and with the results from HPV in situ hybridization assays/p16 immunostaining in the corresponding primary tumors.RESULTSIn total, 64 FNA specimens were analyzed. The Cervista HPV16/18 and/or HPV HR assays were positive in 48 of 64 specimens (75%), and there was a predominance of HPV16 (42 of 48 specimens; 88%). In the 49 specimens that had PCR‐based test results, overall agreement with Cervista assay results was 96% (47 of 49 specimens; κ = 0.883). In the 49 specimens that had PCR‐based HPV16/18 genotyping results, overall agreement with the Cervista HPV16/18 results was 94% (46 of 49 specimens; κ = 0.847). In the 36 primary carcinoma specimens that had valid HPV in situ hybridization/p16 immunostaining results, overall agreement with the Cervista assay results was 92% (33 of 36 specimens; κ = 0.679).CONCLUSIONSCervista HPV16/18 and Cervista HPV HR testing of head and neck FNA specimens is a valid option for determining HPV16/18 status in patients with oropharyngeal carcinoma. Cancer (Cancer Cytopathol) 2014;122:96–103. © 2013 American Cancer Society.
Distribution of vesicular glutamate transporter 2 in auditory and song control brain regions in the adult zebra finch (Taeniopygia guttata)
Authors: Karim Mohammad Rabiul , Saito Shouichiro , Atoji Yasuro 
Published: December 2013

ABSTRACTThe songbird brain has a system of interconnected nuclei that are specialized for singing and song learning. Wada et al. (2004; J. Comp. Neurol. 476:44–64) found a unique distribution of the mRNAs for glutamate receptor subunits in the song control brain areas of songbirds. In conjunction with data from electrophysiological studies, these finding indicate a role for the glutamatergic neurons and circuits in the song system. This study examines vesicular glutamate transporter 2 (VGLUT2) mRNA and protein expression in the zebra finch brain, particularly in auditory areas and song nuclei. In situ hybridization assays for VGLUT2 mRNA revealed high levels of expression in the ascending auditory nuclei (magnocellular, angular, and laminar nuclei; dorsal part of the lateral mesencephalic nucleus; ovoidal nucleus), high or moderate levels of expression in the telencephalic auditory areas (cudomedial mesopallium, field L, caudomedial nidopallium), and expression in the song nuclei (HVC, lateral magnocellular nucleus of the anterior nidopallium, robust nucleus of the arcopallium), where levels of expression were greater than in the surrounding brain subdivisions. Area X did not show expression of VGLUT2 mRNA. Nuclei in the descending motor pathway (dorsomedial nucleus of the intercollicular complex, retroambigual nucleus, tracheosyringeal motor nucleus of the hypoglossal nerve) expressed VGLUT2 mRNA. The target nuclei of VGLUT2 mRNA‐expressing nuclei showed immunoreactivity for VGLUT2 as well as hybridization signals for the mRNA of glutamate receptor subunits. The present findings demonstrate the origins and targets of glutamatergic neurons and indicate a central role for glutamatergic circuits in the auditory and song systems in songbirds. J. Comp. Neurol. 522:2129–2151, 2014. © 2013 Wiley Periodicals, Inc.
Fluorescent Nanodiamonds with Bioorthogonally Reactive Protein‐Resistant Polymeric Coatings
Authors: Rehor Ivan , Mackova Hana , Filippov Sergey K. , Kucka Jan , Proks Vladimir , Slegerova Jitka , Turner Stuart , Van Tendeloo Gustaaf , Ledvina Miroslav , Hruby Martin , Cigler Petr 
Published: December 2013

AbstractThe novel synthesis of a polymeric interface grown from the surface of bright fluorescent nanodiamonds is reported. The polymer enables bioorthogonal attachment of various molecules by click chemistry; the particles are resistant to nonspecific protein adsorption and show outstanding colloidal stability in buffers and biological media. The coating fully preserves the unique optical properties of the nitrogen‐vacancy centers that are crucial for bioimaging and sensoric applications.
Vagal regulation and internalizing psychopathology among adolescents exposed to childhood adversity
Authors: McLaughlin Katie A. , Alves Sonia , Sheridan Margaret A. 
Published: December 2013

ABSTRACTChildhood adversity (CA) is strongly associated with youth psychopathology. Identifying factors that reduce vulnerability following CA is critical for developing preventive interventions. Vagal tone and vagal reactivity following psychosocial stressors might influence psychopathology among youths exposed to CA. We acquired heart period and impedance cardiography data to calculate respiratory sinus arrhythmia (RSA) and preejection period (PEP) from 157 adolescents aged 13–17 years at rest and during the Trier Social Stress Test (TSST). Internalizing and externalizing symptoms and multiple forms of CA were assessed. Resting RSA and RSA reactivity interacted with CA in predicting internalizing but not externalizing psychopathology; CA was unassociated with internalizing problems in adolescents with high resting RSA and RSA reactivity. No interactions were observed with PEP. High resting RSA predicted greater vagal rebound and accelerated heart rate recovery following the TSST, highlighting one potential mechanism underlying low internalizing symptoms following CA among youths with high vagal tone. © 2013 Wiley Periodicals, Inc. Dev Psychobiol 56: 1036–1051, 2014.
The Chemiexcitation of the Chemiluminescence of Lophine Peroxide Anions via a Partially Cyclic Transition State
Authors: Lu Gonghao , Wada Jun , Kimoto Takashi , Iga Hiroshi , Nishigawa Hideki , Kimura Masaru , Hu Zhizhi 
Published: December 2013

AbstractIt was shown that acyclic intermediates play a role in the chemiexcitation of the chemiluminescence (CL) of lophine peroxides in addition to the dioxetane intermediates. Because the CL efficiencies of position‐isomers (R)‐9 and (R)‐10, which theoretically give the common dioxetane intermediate, were different, the different CL efficiencies are attributable to the CL mechanism involving a partially cyclic transition structure at the chemiexcitation step.
Planetary dune analogues: a special issue on integrating models, remote sensing and field data
Authors: Bishop Mark A. 
Published: December 2013

ABSTRACTThis article reports on the Special Issue of Earth Surface Processes and Landforms dedicated to planetary dune analogues and the advances that have been made through the integration of remote sensing and terrestrial field data to better model and understand aeolian systems. The 11 articles presented demonstrate a spectrum of analytical techniques that are employed to investigate ripples, dunes, draa and ergs across a variety of spatial and temporal scales. Nine of the papers involve innovative research about aeolian bedforms and processes, while the final two papers are examples of how vast quantities of data may be organized and scrutinized using a GIScience approach. Based on these 11 papers and the many abstracts archived in a series of three planetary dunes workshops at the Lunar Planetary Institute (http://www.lpi.usra.edu/publications/abstracts.shtml; LPI Contributions 1403, 1552, and 1673) it is evident that there exists diverse and complementary approaches to the comparative study of landforms and processes for terrestrial and extra‐terrestrial aeolian landscapes that is driven by a vibrant international community of scientists and educators that engage in the cross‐fertilization of ideas. Copyright © 2014 John Wiley & Sons, Ltd.
Omega‐3 fatty acid biomarkers and subsequent depressive symptoms
Authors: Persons Jane E. , Robinson Jennifer G. , Ammann Eric M. , Coryell William H. , Espeland Mark A. , Harris William S. , Manson JoAnn E. , Fiedorowicz Jess G. 
Published: December 2013

ObjectiveWe sought to determine the relationship between the omega‐3 fatty acid content of red blood cell membranes (RBC), in particular docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), and baseline and new‐onset depressive symptoms in post‐menopausal women. We secondarily sought to characterize the association between dietary omega‐3 fatty acid intake and depressive symptomatology.MethodsStudy participants included 7086 members of the Women's Health Initiative Memory Study (aged 63–81 years) who had an assessment of RBC omega‐3 fatty acid concentrations at the baseline screening visit. Depressive symptoms at baseline and follow‐up were characterized using the Burnam eight‐item scale for depressive disorders (Center for Epidemiologic Studies Depression Scale/Diagnostic Interview Schedule short form) and secondarily additionally inferred by antidepressant medication use.ResultsIn multivariable‐adjusted models, our primary exposure, RBC DHA + EPA, was not related to depressive symptoms by any measure at baseline or follow‐up, nor were RBC total omega‐3, DHA, or EPA (all p > 0.2). In contrast, dietary intake of omega‐3 was positively associated with depressive symptoms at baseline (adjusted odds ratio 1.082, 95% confidence interval 1.004–1.166; p = 0.04 for dietary DHA + EPA and Burnam score ≥0.06), although this generally did not persist at follow‐up.ConclusionNo relationship between RBC omega‐3 levels and subsequent depressive symptoms was evident, and associations between dietary omega‐3 and depressive symptoms were variable. Biomarkers of omega‐3 status do not appear to be related to risk of new depression in post‐menopausal women. Copyright © 2013 John Wiley & Sons, Ltd.