bluuebunny/crossref_metadata_2025_split huggingface dataset:
Total Synthesis of Macrocyclic Dysoxylactam A
Authors: Prabhakar Reddy D. , Yu Biao 
Published: July 2020

AbstractThe total synthesis of dysoxylactam A, a novel 17‐membered macrolactam with potent multi‐drug‐resistant reversing activities, has been achieved, starting from 4‐pentene‐1‐al in a longest linear sequence of 17 steps and 9.5% overall yield. The key transformations consist of iterative aldol and ring‐closing metathesis reactions for the construction of the stereochemically enriched polypropionate scaffold and the macrocycle, respectively.
The HPA Axis under Stress and Aging: Individual Vulnerability is Associated with Behavioral Patterns and Exposure Time
Authors: Goncharova Nadezhda D. 
Published: July 2020

AbstractWith aging, incidence of severe stress‐related diseases increases. However, mechanisms, underlying individual vulnerability to stress and age‐related diseases are not clear. The goal of this review is to analyze finding from the recent literature on age‐related characteristics of the hypothalamic‐pituitary‐adrenal (HPA) axis associated with stress reactivity in animals that show behavioral signs of anxiety and depression under mild stress, and in human patients with anxiety disorders and depression with emphasis on the impact of the circadian rhythm and the negative feedback mechanisms involved in the stress response. One can conclude that HPA axis reaction to psycho‐emotional stress, at least acute stress, increases in the aged individuals with anxiety and depression behavior. Elevated stress reactivity is associated with disruption of the circadian rhythm and the mineralocorticoid receptor‐mediated glucocorticoid negative feedback. The disordered function of the HPA axis in individuals with anxiety and depression behavior can contribute to aging‐related pathology.
Wide‐surface pore microfiltration membrane drastically improves sieving decay in TFF‐based perfusion cell culture and streamline chromatography integration for continuous bioprocessing
Authors: Pinto Nuno D. S. , Brower Mark 
Published: July 2020

AbstractAlthough several compelling benefits for bioprocess intensification have been reported, the need for a streamlined integration of perfusion cultures with capture chromatography still remains unmet. Here, a robust solution is established by conducting tangential flow filtration‐based perfusion with a wide‐surface pore microfiltration membrane. The resulting integrated continuous bioprocess demonstrated negligible retention of antibody, DNA, and host cell proteins in the bioreactor with average sieving coefficients of 98 ± 1%, 124 ± 28%, and 109 ± 27%, respectively. Further discussion regarding the potential membrane fouling mechanisms is also provided by comparing two membranes with different surface pore structures and the same hollow fiber length, total membrane area, and chemistry. A cake‐growth profile is reported for the narrower surface pore, 0.65‐µm nominal retention perfusion membrane with final antibody sieving coefficients ≤70%. Whereas the sieving coefficient remained ≥85% during 40 culture days for the wide‐surface pore, 0.2‐µm nominal retention rating membrane. The wide‐surface pore structure, confirmed by scanning electron microscopy imaging, minimizes the formation of biomass deposits on the membrane surface and drastically improves product sieving. This study not only offers a robust alternative for integrated continuous bioprocess by eliminating additional filtration steps while overcoming sieving decay, but also provides insight into membranes' fouling mechanism.
A novel TFG c.793C>G mutation in a Chinese pedigree with Charcot‐Marie‐Tooth disease 2
Authors: Wu Ding‐Wen , Li Yanfang , Yin Xinzhen , Zhang Baorong 
Published: July 2020

AbstractIntroductionMutations within TFG gene were recently reported to cause Charcot‐Marie‐Tooth disease 2 (CMT2). However, only few pedigrees were documented so far. Here, we reported a Chinese CMT2 pedigree with 8 affected cases and a novel TFG mutation.MethodsClinical evaluation and electrophysiological study were performed in all the affected individuals. Whole‐exome sequencing was conducted, followed by the Sanger sequencing and co‐segregation analysis to verify the variants.ResultsAll cases presented with a phenotype of CMT2, including slowly progressive symmetrical muscle atrophy and weakness predominantly in the distal limbs. Sensory loss in the distal limbs was present in the proband and his father. Age at onset ranged from 37 to 44 years, and was younger in male cases, compared with female cases. Nerve conduction study revealed normal motor nerve conduction velocity but decreased compound muscle action potential. Electromyography test revealed fibrillation potential and positive sharp waves. The creatine kinase activity was increased in all cases. After genetic investigations, we identified a novel TFG c.793C>G (p.Pro265Ala) mutation in the family. This mutation alters the conserved amino acid residue and is absent in 1000G, ExAC, dbSNP, EP6500, and 200 in‐house controls. It co‐segregated with the disease in the family.ConclusionsOur report provided additional evidence that the heterozygous TFG mutations were associated with CMT2.
Dual MGMT inactivation by promoter hypermethylation and loss of the long arm of chromosome 10 in glioblastoma
Authors: Richard Sophie , Tachon Gaëlle , Milin Serge , Wager Michel , Karayan‐Tapon Lucie 
Published: July 2020

AbstractBackgroundEpigenetic inactivation of O6‐methylguanine‐methyltransferase (MGMT) gene by methylation of its promoter is predictive of Temozolomid (TMZ) response in glioblastoma (GBM). MGMT is located on chromosome 10q26 and the loss of chromosome 10q is observed in 70% of GBMs. In this study, we assessed the hypothesis that the dual inactivation of MGMT, by hypermethylation of MGMT promoter and by loss the long arm of chromosome 10 (10q), may confer greater sensitivity to TMZ.MethodsA total of 149 tumor samples from patients diagnosed with GBM based on the WHO 2016 classification were included in this retrospective study between November 2016 and December 2018. Methylation status of MGMT promoter was evaluated by pyrosequencing and status of chromosome 10q was assessed by array comparative genomic hybridization.ResultsGlioblastoma patients with chromosome 10q loss associated with hypermethylation of MGMT promoter had significantly longer overall survival (OS) (P = .0024) and progression‐free survival (PFS) (P = .031). Indeed, median OS of patients with dual inactivation of MGMT was 21.5 months compared to 12 months and 8.1 months for groups with single MGMT inactivation by hypermethylation and by 10q loss, respectively. The group with no MGMT inactivation had 9.5 months OS. Moreover, all long‐term survivors with persistent response to TMZ treatment (OS ≥ 30 months) displayed dual inactivation of MGMT.ConclusionsOur data suggest that the molecular subgroup characterized by the dual inactivation of MGMT receives greater benefit from TMZ treatment. The results of our study may be of immediate clinical interest since chromosome 10q status and methylation of MGMT promoter are commonly determined in routine practice.
Organic defaults in online‐shopping: Immediate effects but no spillover to similar choices
Authors: Kuhn Sascha , Ihmels Max , Kutzner Florian 
Published: July 2020

AbstractChanging defaults—the preselection that becomes effective without active choice—is becoming a prominent policy tool, after having been proven to be effective in areas as varied as retirement savings, organ donation and product customization. Yet, little is known about how default effects spill over to subsequent similar behaviors. In an online shopping scenario, we found standard default effects on the share of organically produced products in the overall selection of products. These effects did not spill over to subsequent active shopping choices. This was true for defaults that were hard and easy to change (Exp. 1, N = 90), for immediate and delayed subsequent choices (Exp. 2, N = 106) and for self‐selected defaults (Exp. 3, N = 181). These findings suggest that the reach and scalability of default manipulations in policy making may be limited, but also speak against the possibility for negative spillover.
Bioimaging and Biodistribution of the Metal‐Ion‐Controlled Self‐Assembly of PYY3–36 Studied by SPECT/CT
Authors: Kalomoiri Panagiota , Rodríguez‐Rodríguez Cristina , Sørensen Kasper K. , Bergamo Marta , Saatchi Katayoun , Häfeli Urs O. , Jensen Knud J. 
Published: July 2020

AbstractThe controlled self‐assembly of peptide‐ and protein‐based pharmaceuticals is of central importance for their mode of action and tuning of their properties. Peptide YY3–36 (PYY3–36) is a 36‐residue peptide hormone that reduces food intake when peripherally administered. Herein, we describe the synthesis of a PYY3–36 analogue functionalized with a metal‐ion‐binding 2,2’‐bipyridine ligand that enables self‐assembly through metal complexation. Upon addition of CuII, the bipyridine‐modified PYY3–36 peptide binds stoichiometric quantities of metal ions in solution and contributes to the organization of higher‐order assemblies. In this study, we aimed to explore the size effect of the self‐assembly in vivo by using non‐invasive quantitative single‐photon emission computed tomography/computed tomography (SPECT/CT) imaging. For this purpose, bipyridine‐modified PYY3–36 was radiolabeled with a chelator holding 111InIII, followed by the addition of CuII to the bipyridine ligand. SPECT/CT imaging and biodistribution studies showed fast renal clearance and accumulation in the kidney cortex. The radiolabeled bipyridyl‐PYY3–36 conjugates with and without CuII presented a slightly slower excretion 1 h post injection compared to the unmodified‐PYY3–36, thus demonstrating that higher self‐assemblies of the peptide might have an effect on the pharmacokinetics.
Self‐Emergent Protocells Generated in an Aqueous Solution with Binary Macromolecules through Liquid‐Liquid Phase Separation
Authors: Sakuta Hiroki , Fujita Fumika , Hamada Tsutomu , Hayashi Masahito , Takiguchi Kingo , Tsumoto Kanta , Yoshikawa Kenichi 
Published: July 2020

AbstractRecently, liquid–liquid phase separation (LLPS) has attracted considerable attention among researchers in the life sciences as a plausible mechanism for the generation of microstructures inside cells. LLPS occurs through multiple nonspecific interactions and does not always require a lock‐and‐key interaction with a binary macromolecular solution. The remarkable features of LLPS include the non‐uniform localization and concentration of solutes, resulting in the ability to isolate certain chemical systems and thereby parallelize multiple chemical reactions within the limited space of a living cell. We report that, by using the macromolecules, poly(ethylene glycol) (PEG) and dextran, that exhibit LLPS in an aqueous solution, cell‐sized liposomes are spontaneously formed therein in the presence of phospholipids. In this system, LLPS is generated through the depletion effect of macromolecules. The results showed that cell‐like microdroplets entrapping DNA wrapped by a phospholipid layer emerge in a self‐organized manner.
Unresectable cutaneous metastatic tumor in the arm that underwent complete remission after radiotherapy
Authors: Oike Takahiro , Adachi Akiko , Shirai Katsuyuki , Ohno Tatsuya 
Published: July 2020

AbstractCutaneous metastasis of solid malignancies can cause severe disfigurement, which reduces quality of life (QOL). This case indicates potential utility of photon radiotherapy for this disease, leading to recovery of QOL.
Heterochiral DNA with Complementary Strands with α‐d and β‐d Configurations: Hydrogen‐Bonded and Silver‐Mediated Base Pairs with Impact of 7‐Deazapurines Replacing Purines
Authors: Chai Yingying , Guo Xiurong , Leonard Peter , Seela Frank 
Published: July 2020

AbstractHeterochiral DNA with hydrogen‐bonded and silver‐mediated base pairs have been constructed using complementary strands with nucleosides with α‐d or β‐d configuration. Anomeric phosphoramidites were employed to assemble the oligonucleotides. According to the Tm values and thermodynamic data, the duplex stability of the heterochiral duplexes was similar to that of homochiral DNA, but mismatch discrimination was better in heterochiral DNA. Replacement of purines by 7‐deazapurines resulted in stable parallel duplexes, thereby confirming Watson–Crick‐type base pairing. When cytosine was facing cytosine, thymine or adenine residues, duplex DNA formed silver‐mediated base pairs in the presence of silver ions. Although the CD spectra of single strands with α‐d configuration display mirror‐like shapes to those with the β‐d configuration, the CD spectra of the hydrogen‐bonded duplexes and those with a limited number of silver pairs show a B‐type double helix almost indistinguishable from natural DNA. Nonmelting silver ion–DNA complexes with entirely different CD spectra were generated when the number of silver ions was equal to the number of base pairs.
Trifluoromethylation of [AuF3(SIMes)]: Preparation and Characterization of [Au(CF3)xF3−x(SIMes)] (x=1–3) Complexes
Authors: Winter Marlon , Limberg Niklas , Ellwanger Mathias A. , Pérez‐Bitrián Alberto , Sonnenberg Karsten , Steinhauer Simon , Riedel Sebastian 
Published: July 2020

AbstractTrifluoromethylation of [AuF3(SIMes)] with the Ruppert–Prakash reagent TMSCF3 in the presence of CsF yields the product series [Au(CF3)xF3−x(SIMes)] (x=1–3). The degree of trifluoromethylation is solvent dependent and the ratio of the species can be controlled by varying the stoichiometry of the reaction, as evidenced from the 19F NMR spectra of the corresponding reaction mixtures. The molecular structures in the solid state of trans‐[Au(CF3)F2(SIMes)] and [Au(CF3)3(SIMes)] are presented, together with a selective route for the synthesis of the latter complex. Correlation of the calculated SIMes affinity with the carbene carbon chemical shift in the 13C NMR spectrum reveals that trans‐[Au(CF3)F2(SIMes)] and [Au(CF3)3(SIMes)] nicely follow the trend in Lewis acidities of related organo gold(III) complexes. Furthermore, a new correlation between the Au−Ccarbene bond length of the molecular structure in the solid state and the chemical shift of the carbene carbon in the 13C NMR spectrum is presented.
Ce‐Doped Ordered Mesoporous Cobalt Ferrite Phosphides as Robust Catalysts for Water Oxidation
Authors: Huang Yarong , Li Menggang , Yang Weiwei , Yu Yongsheng , Hao Sue 
Published: July 2020

AbstractControllable synthesis and rational design of ordered nanostructures are crucial for their renewable energy applications. In this work, a mesoporous CoP/Fe2P doped with 5 % Ce by a simple nanocasting method is designed as a superior electrocatalyst for the oxygen evolution reaction (OER). The well‐designed composite delivers an efficient electrocatalytic activity with a low overpotential of 250 mV at 10 mA cm−2 and excellent long‐term stability with no degradation after 10 h of electrochemical OER test, superior to that of the state‐of‐the‐art RuO2 electrocatalyst in alkaline electrolyte. A comprehensive analysis demonstrates that the outstanding OER performance is due to the desirable combination of the highly exposed active centers in the Ce‐doped bimetallic phosphides, efficient mass transfer, and effective electron conduction owing to the hierarchically mesoporous hybridization. Furthermore, the synergistic effect between Ce and CoP/Fe2P accelerates the migration rate of electrons/ions and increases the electrochemical active area. This excellent OER performance observed by Ce doping of CoP/Fe2P makes them possible candidates toward OER in alkaline electrolytes.
Electrophilicity Scale of Activated Amides: 17O NMR and 15N NMR Chemical Shifts of Acyclic Twisted Amides in N−C(O) Cross‐Coupling
Authors: Ielo Laura , Pace Vittorio , Holzer Wolfgang , Rahman Md. Mahbubur , Meng Guangrong , Szostak Roman , Szostak Michal 
Published: July 2020

AbstractThe structure and properties of amides are of tremendous interest in organic synthesis and biochemistry. Traditional amides are planar and the carbonyl group non‐electrophilic due to nN→π*C=O conjugation. In this study, we report electrophilicity scale by exploiting 17O NMR and 15N NMR chemical shifts of acyclic twisted and destabilized acyclic amides that have recently received major attention as precursors in N‐C(O) cross‐coupling by selective oxidative addition as well as precursors in electrophilic activation of N‐C(O) bonds. Most crucially, we demonstrate that acyclic twisted amides feature electrophilicity of the carbonyl group that ranges between that of acid anhydrides and acid chlorides. Furthermore, a wide range of electrophilic amides is possible with gradually varying carbonyl electrophilicity by steric and electronic tuning of amide bond properties. Overall, the study quantifies for the first time that steric and electronic destabilization of the amide bond in common acyclic amides renders the amide bond as electrophilic as acid anhydrides and chlorides. These findings should have major implications on the fundamental properties of amide bonds.
Structural Transformation of the 2‐(p‐Aminophenyl)‐1‐hydroxyinden‐3‐ylmethyl Chromophore as a Photoremovable Protecting Group
Authors: Sasaki Miyu , Tran Bao Nguyen Linh , Yabumoto Sohshi , Nakagawa Tatsuo , Abe Manabu 
Published: July 2020

AbstractPhotoremovable protecting groups (PPGs) have attracted much attention not only in the field of organic synthesis but also in biology and materials science because of the spatiotemporally controlled release of various functional molecules upon photolysis. In this study, a new PPG, the 2‐(p‐aminophenyl)‐1‐hydroxyinden‐3‐ylmethyl (pAPHi) chromophore, is designed and synthesized for the efficient and fast release of functional molecules with high conversion yields. The photolysis of caged benzoic acid with the pAPHi chromophore in dimethyl sulfoxide released benzoic acid in 96 % yield, with a decomposition quantum yield of 13 %. A high quantum yield of 51 % was observed with the clean formation of benzoic acid (94 % yield) in methanol. Transient absorption spectroscopic analyses clarified the generation of an intermediate carbocation as well as its reactivity.
Charge‐Transfer Kinetics of The Solid‐Electrolyte Interphase on Li4Ti5O12Thin‐Film Electrodes
Authors: Nasara Ralph Nicolai , Ma Wen , Kondo Yasuyuki , Miyazaki Kohei , Miyahara Yuto , Fukutsuka Tomokazu , Lin Che‐an , Lin Shih‐kang , Abe Takeshi 
Published: July 2020

AbstractCharge‐transfer kinetics between electrodes and electrolytes critically determines the performance of lithium‐ion batteries (LIBs). Lithium titanate defect spinel (Li4Ti5O12, LTO) is a safe and durable anode material, but its relatively low energy density limits the range of applications. Utilizing the low potential region of LTO is a straightforward strategy for increasing energy density. However, the electrochemical characteristics of LTO at low potentials and the properties of the solid‐electrolyte interphase (SEI) on LTO are not well understood. Here, we investigate the charge‐transfer kinetics of the SEI formed between model LTO thin‐film electrodes and organic electrolytes with distinct solvation ability using AC impedance spectroscopy whereas their stability was assessed by cyclic voltammetry of ferrocene. With the SEI film on LTO, the Li+desolvation was rate‐determining step but with larger activation energies, which showed a strong dependence on the solvation ability of electrolyte. The activation energies of desolvation for the fluoroethylene carbonate+dimethyl carbonate‐ and ethylene carbonate+diethyl carbonate‐based systems increased from 35 and 55 to 44 and 67 kJ mol−1, respectively, and that for the propylene carbonate‐based system did not noticeably change at around 67 kJ mol−1. In addition, the SEI passivation of LTO was much slower than that of graphite, and the rate also strongly depended on the solvation ability of the electrolyte. Understanding the surface properties of LTO at low potentials opens the door for high‐energy‐density LTO‐based LIBs.
Aromatic Ester‐Functionalized Ionic Liquid for Highly Efficient CO2 Electrochemical Reduction to Oxalic Acid
Authors: Yang Yingliang , Gao Hongshuai , Feng Jiaqi , Zeng Shaojuan , Liu Lei , Liu Licheng , Ren Baozeng , Li Tao , Zhang Suojiang , Zhang Xiangping 
Published: July 2020

AbstractElectrochemical reduction of CO2 into valuable chemicals is a significant route to utilize CO2 resources. Among various electroreduction products, oxalic acid (H2C2O4) is an important chemical for pharmaceuticals, rare earth extraction, and metal processing. Here, an aprotic aromatic ester‐functionalized ionic liquid (IL), 4‐(methoxycarbonyl) phenol tetraethylammonium ([TEA][4‐MF‐PhO]), was designed as an electrolyte for CO2 electroreduction into oxalic acid. It exhibited a large oxalic acid partial current density of 9.03 mA cm−2 with a faradaic efficiency (FE) of 86 % at −2.6 V (vs. Ag/Ag+), and the oxalic acid formation rate was as high as 168.4 μmol cm−2 h−1, which is the highest reported value to date. Moreover, the results of density functional theory calculations demonstrated that CO2 was efficiently activated to a −COOH intermediate by bis‐active sites of the aromatic ester anion via the formation of a [4‐MF‐PhO‐COOH]− adduct, which finally dimerized into oxalic acid.
Coupling 0D and 1D Carbons for Electrochemical Hydrogen Production Promoted by a Percolation Mechanism
Authors: Dou Zhi , Du Na , Liu Xue , Wu Qiuhua , Wu Qiong , Fu Yang , Zhang Guolin , Ma Tianyi 
Published: July 2020

AbstractDeveloping hydrogen evolution reaction (HER) electrocatalysts with high activity, durability and moderate price is essential for sustainable hydrogen energy utilization. Here, the facile coupling of carbon dots (CDs, 0D carbon materials) and carbon fibres (CFs, 1D carbon materials) for enhanced electrochemical hydrogen production was demonstrated. Electrochemical tests revealed that the CD/CF catalysts showed outstanding catalytic activity with a small overpotential of 280 mV at the current density of 10 mA cm−2, a small Tafel slope of 87 mV dec−1 and prominent durability. Percolation theory was for the first time introduced to interpret the catalytic mechanism of the CD/CF catalysts. The special morphology assembled by the 0D carbons constituted the percolating clusters and promoted electron transport throughout the 1D carbons. The strategy and theory can be adapted to general electrocatalytic applications for achieving and interpreting precise tuning on highly efficient electron transfer in electrocatalysts.
Trimetallic MOF‐74 Films Grown on Ni Foam as Bifunctional Electrocatalysts for Overall Water Splitting
Authors: Zhou Weide , Xue Ziqian , Liu Qinglin , Li Yinle , Hu Jianqiang , Li Guangqin 
Published: July 2020

AbstractDeveloping earth‐abundant and high‐performance electrocatalysts for water splitting has long been a vital research in energy conversion field. Herein, we report the preparation of a series of trimetallic uniform MnxFeyNi‐MOF‐74 films in‐situ grown on nickel foam, which can be utilized as bifunctional electrocatalysts towards overall water splitting in alkaline media. The introduction of Mn can simultaneously regulate the morphology of MOF‐74 to form uniform film and modulate electronic structure of Fe to form more Fe(II)−O−Fe(III) motifs, which is conducive to the exposure of active sites and stabilizing high‐valent metal sites. The optimized Mn0.52Fe0.71Ni‐MOF‐74 film electrode showed excellent electrocatalytic performance, affording a current density of 10 mA ⋅ cm−2 at an overpotential of 99 mV for HER and 100 mA ⋅ cm−2 at an overpotential of 267 mV for OER, respectively. Assembled as an electrolyser, Mn0.52Fe0.71Ni‐MOF‐74 film electrode exhibited excellent performance towards overall water splitting, with ultralow overpotential of 245 and 462 mV to achieve current density of 10 and 100 mA ⋅ cm−2, respectively. This work provides a new view to develop multi‐metal MOF‐based electrocatalysts.