bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Nanoscale Metal–Organic Framework to Mediate Photodynamic Therapy and Deliver CpG Oligodeoxynucleotides to Enhance Antigen Presentation and Cancer Immunotherapy
Authors: Ni Kaiyuan , Luo Taokun , Lan Guangxu , Culbert August , Song Yang , Wu Tong , Jiang Xiaomin , Lin Wenbin 
Published: October 2019

AbstractCheckpoint blockade immunotherapy (CBI) awakes a host innate immune system and reactivates cytotoxic T cells to elicit durable response in some cancer patients. Now, a cationic nanoscale metal–organic framework, W‐TBP, is used to facilitate tumor antigen presentation by enabling immunogenic photodynamic therapy (PDT) and promoting the maturation of dendritic cells (DCs). Comprised of dinuclear WVI secondary building units and photosensitizing 5,10,15,20‐tetra(p‐benzoato)porphyrin (TBP) ligands, cationic W‐TBP mediates PDT to release tumor associated antigens and delivers immunostimulatory CpG oligodeoxynucleotides to DCs. The enhanced antigen presentation synergizes with CBI to expand and reinvigorate cytotoxic T cells, leading to superb anticancer efficacy and robust abscopal effects with >97 % tumor regression in a bilateral breast cancer model.
Characterization of Radical SAM Adenosylhopane Synthase, HpnH, which Catalyzes the 5′‐Deoxyadenosyl Radical Addition to Diploptene in the Biosynthesis of C35 Bacteriohopanepolyols
Authors: Sato Shusuke , Kudo Fumitaka , Rohmer Michel , Eguchi Tadashi 
Published: October 2019

AbstractAdenosylhopane is a crucial intermediate in the biosynthesis of bacteriohopanepolyols, which are widespread prokaryotic membrane lipids. Herein, it is demonstrated that reconstituted HpnH, a putative radical S‐adenosyl‐l‐methionine (SAM) enzyme, commonly encoded in the hopanoid biosynthetic gene cluster, converts diploptene into adenosylhopane in the presence of SAM, flavodoxin, flavodoxin reductase, and NADPH. NMR spectra of the enzymatic reaction product were identical to those of synthetic (22R)‐adenosylhopane, indicating that HpnH catalyzes stereoselective C−C formation between C29 of diploptene and C5′ of 5′‐deoxyadenosine. Further, the HpnH reaction in D2O‐containing buffer revealed that a D atom was incorporated at the C22 position of adenosylhopane. Based on these results, we propose a radical addition reaction mechanism catalyzed by HpnH for the formation of the C35 bacteriohopane skeleton.
Elucidating the Electrocatalytic CO2 Reduction Reaction over a Model Single‐Atom Nickel Catalyst
Authors: Liu Song , Yang Hong Bin , Hung Sung‐Fu , Ding Jie , Cai Weizheng , Liu Linghui , Gao Jiajian , Li Xuning , Ren Xinyi , Kuang Zhichong , Huang Yanqiang , Zhang Tao , Liu Bin 
Published: October 2019

AbstractDesigning effective electrocatalysts for the carbon dioxide reduction reaction (CO2RR) is an appealing approach to tackling the challenges posed by rising CO2 levels and realizing a closed carbon cycle. However, fundamental understanding of the complicated CO2RR mechanism in CO2 electrocatalysis is still lacking because model systems are limited. We have designed a model nickel single‐atom catalyst (Ni SAC) with a uniform structure and well‐defined Ni‐N4 moiety on a conductive carbon support with which to explore the electrochemical CO2RR. Operando X‐ray absorption near‐edge structure spectroscopy, Raman spectroscopy, and near‐ambient X‐ray photoelectron spectroscopy, revealed that Ni+ in the Ni SAC was highly active for CO2 activation, and functioned as an authentic catalytically active site for the CO2RR. Furthermore, through combination with a kinetics study, the rate‐determining step of the CO2RR was determined to be *CO2−+H+→*COOH. This study tackles the four challenges faced by the CO2RR; namely, activity, selectivity, stability, and dynamics.
Zeolite‐Encaged Single‐Atom Rhodium Catalysts: Highly‐Efficient Hydrogen Generation and Shape‐Selective Tandem Hydrogenation of Nitroarenes
Authors: Sun Qiming , Wang Ning , Zhang Tianjun , Bai Risheng , Mayoral Alvaro , Zhang Peng , Zhang Qinghong , Terasaki Osamu , Yu Jihong 
Published: October 2019

AbstractSingle‐atom catalysts are emerging as a new frontier in heterogeneous catalysis because of their maximum atom utilization efficiency, but they usually suffer from inferior stability. Herein, we synthesized single‐atom Rh catalysts embedded in MFI‐type zeolites under hydrothermal conditions and subsequent ligand‐protected direct H2 reduction. Cs‐corrected scanning transmission electron microscopy and extended X‐ray absorption analyses revealed that single Rh atoms were encapsulated within 5‐membered rings and stabilized by zeolite framework oxygen atoms. The resultant catalysts exhibited excellent H2 generation rates from ammonia borane (AB) hydrolysis, up to 699 min−1 at 298 K, representing the top level among heterogeneous catalysts for AB hydrolysis. The catalysts also showed superior catalytic performance in shape‐selective tandem hydrogenation of various nitroarenes by coupling with AB hydrolysis, giving >99 % yield of corresponding amine products.
Discriminative Detection of Biothiols by Electron Paramagnetic Resonance Spectroscopy using a Methanethiosulfonate Trityl Probe
Authors: Tan Xiaoli , Ji Kaiyun , Wang Xing , Yao Ru , Han Guifang , Villamena Frederick A. , Zweier Jay L. , Song Yuguang , Rockenbauer Antal , Liu Yangping 
Published: October 2019

AbstractBiothiols, such as glutathione (GSH), homocysteine (Hcy), and cysteine (Cys), coexist in biological systems with diverse biological roles. Thus, analytical techniques that can detect, quantify, and distinguish between multiple biothiols are desirable but challenging. Herein, we demonstrate the simultaneous detection and quantitation of multiple biothiols, including up to three different biothiols in a single sample, using electron paramagnetic resonance (EPR) spectroscopy and a trityl‐radical‐based probe (MTST). We term this technique EPR thiol‐trapping. MTST could trap thiols through its methanethiosulfonate group to form the corresponding disulfide conjugate with an EPR spectrum characteristic of the trapped thiol. MTST was used to investigate effects of l‐buthionine sulfoximine (BSO) and pyrrolidine dithiocarbamate (PDTC) on the efflux of GSH and Cys from HepG2 cells.
Development and Investigation of a NASICON‐Type High‐Voltage Cathode Material for High‐Power Sodium‐Ion Batteries
Authors: Chen Mingzhe , Hua Weibo , Xiao Jin , Cortie David , Guo Xiaodong , Wang Enhui , Gu Qinfen , Hu Zhe , Indris Sylvio , Wang Xiao‐Lin , Chou Shu‐Lei , Dou Shi‐Xue 
Published: October 2019

AbstractHerein, we introduce a 4.0 V class high‐voltage cathode material with a newly recognized sodium superionic conductor (NASICON)‐type structure with cubic symmetry (space group P213), Na3V(PO3)3N. We synthesize an N‐doped graphene oxide‐wrapped Na3V(PO3)3N composite with a uniform carbon coating layer, which shows excellent rate performance and outstanding cycling stability. Its air/water stability and all‐climate performance were carefully investigated. A near‐zero volume change (ca. 0.40 %) was observed for the first time based on in situ synchrotron X‐ray diffraction, and the in situ X‐ray absorption spectra revealed the V3.2+/V4.2+ redox reaction with high reversibility. Its 3D sodium diffusion pathways were demonstrated with distinctive low energy barriers. Our results indicate that this high‐voltage NASICON‐type Na3V(PO3)3N composite is a competitive cathode material for sodium‐ion batteries and will receive more attention and studies in the future.
Quantitative Particle Uptake by Cells as Analyzed by Different Methods
Authors: Ashraf Sumaira , Hassan Said Alaa , Hartmann Raimo , Assmann Marcus‐Alexander , Feliu Neus , Lenz Peter , Parak Wolfgang J. 
Published: October 2019

AbstractThere is a large number of two‐dimensional static in vitro studies about the uptake of colloidal nano‐ and microparticles, which has been published in the last decade. In this Minireview, different methods used for such studies are summarized and critically discussed. Supplementary experimental data allow for a direct comparison of the different techniques. Emphasis is given on how quantitative parameters can be extracted from studies in which different experimental techniques have been used, with the goal of allowing better comparison.
Nanographenes: Ultrastable, Switchable, and Bright Probes for Super‐Resolution Microscopy
Authors: Liu Xiaomin , Chen Shih‐Ya , Chen Qiang , Yao Xuelin , Gelléri Márton , Ritz Sandra , Kumar Sachin , Cremer Christoph , Landfester Katharina , Müllen Klaus , Parekh Sapun H. , Narita Akimitsu , Bonn Mischa 
Published: October 2019

AbstractSuper‐resolution fluorescence microscopy has enabled important breakthroughs in biology and materials science. Implementations such as single‐molecule localization microscopy (SMLM) and minimal emission fluxes (MINFLUX) microscopy in the localization mode exploit fluorophores that blink, i.e., switch on and off, stochastically. Here, we introduce nanographenes, namely large polycyclic aromatic hydrocarbons that can also be regarded as atomically precise graphene quantum dots, as a new class of fluorophores for super‐resolution fluorescence microscopy. Nanographenes exhibit outstanding photophysical properties: intrinsic blinking even in air, excellent fluorescence recovery, and stability over several months. As a proof of concept for super‐resolution applications, we use nanographenes in SMLM to generate 3D super‐resolution images of silica nanocracks. Our findings open the door for the widespread application of nanographenes in super‐resolution fluorescence microscopy.
Ultrafast Condensation of Carbon Nitride on Electrodes with Exceptional Boosted Photocurrent and Electrochemiluminescence
Authors: Zhao Tingting , Zhou Qing , Lv Yanqin , Han Dan , Wu Kaiqing , Zhao Lufang , Shen Yanfei , Liu Songqin , Zhang Yuanjian 
Published: October 2019

AbstractSemiconducting polymeric carbon nitride (CN) has drawn wide attention ranging from photocatalysis to more recent biosensing owing to unique defect‐tolerated optoelectronic properties and being metal‐free, cheap, and highly stable. However, at the core of electrical–optical interconversion, the preparation of the CN photoelectrode is still challenging. Now, the growth of CN on electrodes is achieved simply by microwave‐assisted condensation in seconds. The ultrafast heating not only addressed the thermodynamic contradiction of precursor volatilization during polymerization but also led to strongly adhesive CN layer on electrodes with gradient carbon‐rich texture, greatly accelerating the electron–hole separation and mobility. Consequently, the CN photoelectrode exhibited a remarkable photocurrent and a record cathodic efficiency of electrochemiluminescence up to 7 times that of benchmark Ru(bpy)3Cl2in aqueous solution.
Bioassay of ferulic acid derivatives as influenza neuraminidase inhibitors
Authors: Cui Man‐Ying , Xiao Meng‐Wu , Xu Lv‐Jie , Chen Yun , Liu Ai‐Lin , Ye Jiao , Hu Ai‐Xi 
Published: October 2019

AbstractFour series of ferulic acid derivatives were designed, synthesized, and evaluated for their neuraminidase (NA) inhibitory activities against influenza virus H1N1 in vitro. The pharmacological results showed that the majority of the target compounds exhibited moderate influenza NA inhibitory activity, which was also better than that of ferulic acid. The two most potent compounds were 1m and 4a with IC50 values of 12.77 ± 0.47 and 12.96 ± 1.34 μg/ml, respectively. On the basis of the biological results, a preliminary structure–activity relationship (SAR) was derived and discussed. Besides, molecular docking was performed to study the possible interactions of compounds 1p, 2d, 3b, and 4a with the active site of NA. It was found that the 4‐OH‐3‐OMe group and the amide group (CON) of ferulic acid amide derivatives were two key pharmacophores for NA inhibitory activity. It is meaningful to further modify the natural product ferulic acid to improve its influenza NA inhibitory activity.
Differential profiles of response inhibition deficit between male children with autism spectrum disorders and schizophrenia
Authors: Shi Li‐juan , Zhou Han‐yu , Shen Yan‐mei , Wang Ya , Fang Yu‐min , He Yu‐qiong , Ou Jian‐jun , Luo Xue‐rong , Cheung Eric F. C. , Chan Raymond C. K. 
Published: October 2019

Autism spectrum disorders (ASD) and schizophrenia (SZ) are both associated with response inhibition impairment. However, the relative pattern of deficits in these two disorders remains unclear. Twenty‐three male children with ASD, 23 male children with SZ, and 32 typically developing male controls were recruited to complete a set of tasks measuring response inhibition in the visual, auditory, and verbal domains. We found that visual, auditory, and verbal response inhibitions were impaired in both children with ASD and children with SZ. Compared with typically developing controls, children with ASD made more commission errors whereas children with SZ responded much slower in the visual response inhibition task. Both clinical groups showed comparable impairment in verbal response inhibition, but children with SZ were more impaired in auditory response inhibition than children with ASD. These different patterns of response inhibition deficit between male children with ASD and SZ may help to differentiate between these two disorders and may be potential targets for intervention. Autism Res 2020, 13: 591–602. © 2019 International Society for Autism Research, Wiley Periodicals, Inc.Lay SummaryIn this study, we found that male children with autism spectrum disorder (ASD) made more commission errors whereas male children with schizophrenia (SZ) responded much slower in the visual response inhibition task. Both clinical groups exhibited comparable impairments in verbal response inhibition, but male children with SZ were more impaired in auditory response inhibition than male children with ASD. Our findings provide potential targets for intervention.
Preparative and Kinetic Analysis of β‐1,4‐ and β‐1,3‐Glucan Phosphorylases Informs Access to Human Milk Oligosaccharide Fragments and Analogues Thereof
Authors: Singh Ravindra Pal , Pergolizzi Giulia , Nepogodiev Sergey A. , de Andrade Peterson , Kuhaudomlarp Sakonwan , Field Robert A. 
Published: October 2019

AbstractThe enzymatic synthesis of oligosaccharides depends on the availability of suitable enzymes, which remains a limitation. Without recourse to enzyme engineering or evolution approaches, herein we demonstrate the ability of wild‐type cellodextrin phosphorylase (CDP: β‐1,4‐glucan linkage‐dependent) and laminaridextrin phosphorylase (Pro_7066: β‐1,3‐glucan linkage‐dependent) to tolerate a number of sugar‐1‐ phosphate substrates, albeit with reduced kinetic efficiency. In spite of catalytic efficiencies of <1 % of the natural reactions, we demonstrate the utility of given phosphorylase–sugar phosphate pairs to access new‐to‐nature fragments of human milk oligosaccharides, or analogues thereof, in multi‐milligram quantities.
Isoindoline‐Based Nitroxides as Bioresistant Spin Labels for Protein Labeling through Cysteines and Alkyne‐Bearing Noncanonical Amino Acids
Authors: Braun Theresa Sophie , Widder Pia , Osswald Uwe , Groß Lina , Williams Lara , Schmidt Moritz , Helmle Irina , Summerer Daniel , Drescher Malte 
Published: October 2019

AbstractElectron paramagnetic resonance (EPR) spectroscopy in combination with site‐directed spin labeling (SDSL) is a powerful tool in protein structural research. Nitroxides are highly suitable spin labeling reagents, but suffer from limited stability, particularly in the cellular environment. Herein we present the synthesis of a maleimide‐ and an azide‐modified tetraethyl‐shielded isoindoline‐based nitroxide (M‐ and Az‐TEIO) for labeling of cysteines or the noncanonical amino acid para‐ethynyl‐l‐phenylalanine (pENF). We demonstrate the high stability of TEIO site‐specifically attached to the protein thioredoxin (TRX) against reduction in prokaryotic and eukaryotic environments, and conduct double electron–electron resonance (DEER) measurements. We further generate a rotamer library for the new residue pENF‐Az‐TEIO that affords a distance distribution that is in agreement with the measured distribution.
A Genetically Encoded Diazirine Analogue for RNA–Protein Photo‐crosslinking
Authors: Dziuba Dmytro , Hoffmann Jan‐Erik , Hentze Matthias W. , Schultz Carsten 
Published: October 2019

AbstractUltraviolent crosslinking is a key experimental step in the numerous protocols that have been developed for capturing and dissecting RNA–protein interactions in living cells. UV crosslinking covalently stalls dynamic interactions between RNAs and the directly contacting RNA‐binding proteins and enables stringent denaturing downstream purification conditions needed for the enrichment and biochemical analysis of RNA–protein complexes. Despite its popularity, conventional 254 nm UV crosslinking possesses a set of intrinsic drawbacks, with the low photochemical efficiency being the central caveat. Here we show that genetically encoded photoreactive unnatural amino acids bearing a dialkyl diazirine photoreactive group can address this problem. Using the human iron regulatory protein 1 (IRP1) as a model RNA‐binding protein, we show that the photoreactive amino acids can be introduced into the protein without diminishing its RNA‐binding properties. A sevenfold increase in the crosslinking efficiency compared to conventional 254 nm UV crosslinking was achieved using the diazirine‐based unnatural amino acid DiAzKs. This finding opens an avenue for new applications of the unnatural amino acids in studying RNA–protein interactions.
Ascorbate Oxidase Mimetic Activity of Copper(II) Oxide Nanoparticles
Authors: He Shao‐Bin , Hu Ai‐Ling , Zhuang Quan‐Quan , Peng Hua‐Ping , Deng Hao‐Hua , Chen Wei , Hong Guo‐Lin 
Published: October 2019

AbstractAlthough oxidase mimetic nanozymes have been widely investigated, specific biological molecules have rarely been explored as substrates, particularly in the case of ascorbate oxidase (AAO) mimetic nanozymes. Herein, we demonstrate for the first time that copper(II) oxide nanoparticles (CuO NPs) catalyze the oxidation of ascorbic acid (AA) by dissolved O2 (as a green oxidant) to form dehydroascorbic acid (DHAA), thus functioning as a new kind of AAO mimic. Under neutral conditions, the Michaelis–Menten constant of CuO NPs (0.1302 mm) is similar to that of AAO (0.0840 mm). Furthermore, the robustness of CuO NPs is greater than that of AAO, thus making them suitable for applications under various conditions. As a demonstration, a fluorescence AA sensor based on the AAO mimetic activity of CuO NPs was developed. To obtain a fluorescent product, o‐phenylenediamine (OPDA) was used to react with the DHAA produced by the oxidation of AA catalyzed by CuO NPs. The developed sensor was cost‐effective and easy to fabricate and exhibited high selectivity/sensitivity with a wide linear range (1.25×10−6 to 1.125×10−4 m) and a low detection limit (3.2×10−8 m). The results are expected to aid in expanding the applicability of oxidase mimetic nanozymes in a variety of fields such as biology, medicine, and detection science.
Photoelectrochemical CO2 Reduction to Formate with the Sacrificial Reagent Free System of Semiconductor Photocatalysts and Formate Dehydrogenase
Authors: Ishibashi Tomoya , Higashi Masanobu , Ikeda Shigeru , Amao Yutaka 
Published: October 2019

AbstractEfficient sacrificial reagent free (and no external bias) photoelectrochemical CO2 reduction to formate with a hybrid system consisting of semiconductor‐based photocatalytic TiO2 nanoparticles, methylviologen (MV) as an electron carrier, and biocatalytic formate dehydrogenase (FDH) was investigated. To develop the sacrificial reagent free photoelectrochemical cell for the CO2 reduction to formate, the photoanode based on TiO2 film and cathode based on the carbon fabric paper (CFP) were separated into two compartments using a proton‐permeable Nafion film to prevent gas diffusion. When the anode was irradiated with Xenon lamp (>300 nm), MV reduction and CO2 reduction to formate with FDH on the cathode side proceeded in this system. For MV reduction with photoelectrochemical cell, MV was reduced using TiO2 film at each pH (6, 7 and 8) without bias, the reduction of MV did not progressed at pH 6. In contrast, MV reduction was progressed at pH 7 or 8. For CO2 reduction to formate in the presence FDH on the cathode side with photoelectrochemical cell, the rate of formate production was estimated to be 31.9 nmol h−1 at pH 8 under continuous irradiation without bias. Moreover, the rates of formate production at pH 7 and 8 were estimated to be 56.5 and 168.8 nmol h−1, respectively under continuous irradiation with bias (0.4 V vs. cathode). By using this system, we have succeeded in constructing CO2 reduction to formate using water as an electron donor, which does not require a sacrificial reagent.
Iron‐Electrocatalyzed C−H Arylations: Mechanistic Insights into Oxidation‐Induced Reductive Elimination for Ferraelectrocatalysis
Authors: Zhu Cuiju , Stangier Maximilian , Oliveira João C. A. , Massignan Leonardo , Ackermann Lutz 
Published: October 2019

AbstractDespite major advances, organometallic C−H transformations are dominated by precious 5d and 4d transition metals, such as iridium, palladium and rhodium. In contrast, the unique potential of less toxic Earth‐abundant 3d metals has been underexplored. While iron is the most naturally abundant transition metal, its use in oxidative, organometallic C−H activation has faced major limitations due to the need for superstoichiometric amounts of corrosive, cost‐intensive DCIB as the sacrificial oxidant. To fully address these restrictions, we describe herein the unprecedented merger of electrosynthesis with iron‐catalyzed C−H activation through oxidation‐induced reductive elimination. Thus, ferra‐ and manganaelectro‐catalyzed C−H arylations were accomplished at mild reaction temperatures with ample scope by the action of sustainable iron catalysts, employing electricity as a benign oxidant.
Controlled Synthesis of Ni‐Doped MoS2 Hybrid Electrode for Synergistically Enhanced Water‐Splitting Process
Authors: Wang Ying , Sun Wenming , Ling Xiaofei , Shi Xiangkai , Li Lanlan , Deng Yida , An Cuihua , Han Xiaopeng 
Published: October 2019

AbstractThe development of high‐efficiency, low‐cost, and earth‐abundant electrocatalysts for overall water splitting remains a challenge. In this work, Ni‐modified MoS2 hybrid catalysts are grown on carbon cloth (Ni‐Mo‐S@CC) through a one‐step hydrothermal treatment. The optimized Ni‐Mo‐S@CC catalyst shows excellent hydrogen evolution reaction (HER) activity with a low overpotential of 168 mV at a current density of 10 mA cm−2 in 1.0 m KOH, which is lower than those of Ni‐Mo‐S@CC (1:1), Ni‐Mo‐S@CC (3:1), and pure MoS2. Significantly, the Ni‐Mo‐S@CC hybrid catalyst also displays outstanding oxygen evolution reaction (OER) activity with a low overpotential of 320 mV at a current density of 10 mA cm−2, and remarkable long‐term stability for 30 h at a constant current density of 10 mA cm−2. Experimental results and theoretical analysis based on density functional theory demonstrate that the excellent electrocatalytic performance can be attributed mainly to the remarkable conductivity, abundant active sites, and synergistic effect of the Ni‐doped MoS2. This work sheds light on a unique strategy for the design of high‐performance and stable electrocatalysts for water‐splitting electrolyzers.