bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phen‐DC3 Induces Refolding of Human Telomeric DNA into a Chair‐Type Antiparallel G‐Quadruplex through Ligand Intercalation
Authors: Ghosh Anirban , Trajkovski Marko , Teulade‐Fichou Marie‐Paule , Gabelica Valérie , Plavec Janez 
Published: August 2022

AbstractHuman telomeric G‐quadruplex DNA structures are attractive anticancer drug targets, but the target's polymorphism complicates the drug design: different ligands prefer different folds, and very few complexes have been solved at high resolution. Here we report that Phen‐DC3, one of the most prominent G‐quadruplex ligands in terms of high binding affinity and selectivity, causes dTAGGG(TTAGGG)3 to completely change its fold in KCl solution from a hybrid‐1 to an antiparallel chair‐type structure, wherein the ligand intercalates between a two‐quartet unit and a pseudo‐quartet, thereby ejecting one potassium ion. This unprecedented high‐resolution NMR structure shows for the first time a true ligand intercalation into an intramolecular G‐quadruplex.
Fast‐Scan Cyclic Voltammetry (FSCV) Reveals Behaviorally Evoked Dopamine Release by Sugar Feeding in the Adult Drosophila Mushroom Body
Authors: Shin Mimi , Venton B. Jill 
Published: August 2022

AbstractDrosophila melanogaster, the fruit fly, is an excellent model organism for studying dopaminergic mechanisms and simple behaviors, but methods to measure dopamine during behavior are needed. Here, we developed fast‐scan cyclic voltammetry (FSCV) to track in vivo dopamine during sugar feeding. First, we employed acetylcholine stimulation to evaluate the feasibility of in vivo measurements in an awake fly. Next, we tested sugar feeding by placing sucrose solution near the fly proboscis. In the mushroom body medial tip, 1 pmol acetylcholine and sugar feeding released 0.49±0.04 μM and 0.31±0.06 μM dopamine, respectively but sugar‐evoked release lasted longer than with acetylcholine. Administering the dopamine transporter inhibitor nisoxetine or D2 receptor antagonist flupentixol significantly increased sugar‐evoked dopamine. This study develops FSCV to measure behaviorally evoked release in fly, enabling Drosophila studies of neurochemical control of reward, learning, and memory behaviors.
Low‐Coordination Single Au Atoms on Ultrathin ZnIn2S4Nanosheets for Selective Photocatalytic CO2Reduction towards CH4
Authors: Si Shenghe , Shou Hongwei , Mao Yuyin , Bao Xiaolei , Zhai Guangyao , Song Kepeng , Wang Zeyan , Wang Peng , Liu Yuanyuan , Zheng Zhaoke , Dai Ying , Song Li , Huang Baibiao , Cheng Hefeng 
Published: August 2022

AbstractSelective CO2photoreduction to hydrocarbon fuels such as CH4is promising and sustainable for carbon‐neutral future. However, lack of proper binding strengths with reaction intermediates makes it still a challenge for photocatalytic CO2methanation with both high activity and selectivity. Here, low‐coordination single Au atoms (Au1‐S2) on ultrathin ZnIn2S4nanosheets was synthesized by a complex‐exchange route, enabling exceptional photocatalytic CO2reduction performance. Under visible light irradiation, Au1/ZnIn2S4catalyst exhibits a CH4yield of 275 μmol g−1 h−1with a selectivity as high as 77 %. As revealed by detailed characterizations and density functional theory calculations, Au1/ZnIn2S4with Au1‐S2structure not only display fast carrier transfer to underpin its superior activity, but also greatly reduce the energy barrier for protonation of *CO and stabilize the *CH3intermediate, thereby leading to the selective CH4generation from CO2photoreduction.
Synthesis of Square Planar Cu4Clusters
Authors: Osei Manasseh Kusi , Mirzaei Saber , Bogetti Xiaowei , Castro Edison , Rahman Mohammad Azizur , Saxena Sunil , Hernández Sánchez Raúl 
Published: August 2022

AbstractTemplate‐assisted synthesis of well‐defined polynuclear clusters remains a challenge for [M4] square planar topologies. Herein, we present a tetraamine scaffoldRL(NH2)4, where L is a rigidified resorcin[4]arene, to direct the formation ofC4‐symmetricRL(NH)4Cu4clusters with Cu−Cu distances around 2.7 Å, suggesting metal‐metal direct interactions are operative since the sum of copper's van der Waals radii is 2.8 Å. DFT calculations display HOMO to HOMO‐3 residing all within a 0.1 eV gap. These four orbitals display significant electron density contribution from the Cu centers suggesting a delocalized electronic structure. The one‐electron oxidized [Cu4]+species was probed by variable temperature X‐band continuous wave‐electron paramagnetic resonance (CW‐EPR), which displays a multiline spectrum at room temperature. This work presents a novel synthetic strategy for [M4] clusters and a new platform to investigate activation of small molecules.
Self‐Assembly of Macrocyclic Triangles into Helicity‐Opposite Nanotwists by Competitive Planar over Point Chirality
Authors: Shang Weili , Zhu Xuefeng , Jiang Yuqian , Cui Jie , Liu Kaiang , Li Tiesheng , Liu Minghua 
Published: August 2022

AbstractWhile helix has elegant biomimetic structures and functionalities, it still remains a big question how the nanoscale helicity evolved from the molecular chiral building blocks across length scales. Herein, macrocyclic triangles composed of achiral edges and chiral vertices were rationally designed, in which the planar chirality emerged due to the restriction of edge rotation by intermolecular stackings and led to a unique chiral self‐assembly. In contrast to the solution systems where the chiroptical property is exclusively dominated by the point chiral vertices, the emerged planar chirality was found to control the chiral self‐assembly, resulting the nanotwist with the handedness determined by the planar chirality. Our work unveiled the self‐assembly behaviors of macrocyclic conformers for the first time and provided a deep understanding on the macrocyclic chirality evolution including the excited‐state chirality.
Differenzierte Peptid‐Multi‐Makrozyklisierungen an der Oberfläche eines helikalen Foldamer‐Templats
Authors: Dengler Sebastian , Douat Céline , Huc Ivan 
Published: August 2022

AbstractEs wurden hybride Sequenzen synthetisiert, die Peptide mit einer Reihe von Cystein‐Resten und aromatische Foldamer‐Helices mit mehreren Chloracetamid‐Funktionen an ihrer Oberfläche umfassen. Solche Produkte können im Prinzip zahlreiche makromultizyklische Thioetherbrücken bilden, indem sie alle Cys‐Reste und alle Chloracetamidfunktionen intramolekular verbinden. Wir zeigen indes, dass die reaktiven Stellen auf der strukturell definierten Helix an solchen Positionen platziert werden können, so dass das Peptid selektiv reagiert, um eine Reihe unterschiedlicher Makrozyklen innerhalb meist eines bevorzugten Produkts zu bilden. Die Reaktionen wurden mittels HPLC überprüft und die Produkte mit zwei, drei oder vier Makrozyklen wurden mittels LC–MS und NMR identifiziert. Die Reihe selektiver Makrozyklisierungen definiert eine Art Reaktionspfad, bei dem ansonsten identische Reaktionsstellen aufgrund ihrer genauen Positionierung im Raum nacheinander beteiligt sind. Die Reaktionspfade lassen sich weitgehend auf der Grundlage struktureller Überlegungen und der Annahme, dass sich kleinere Makrozyklen schneller bilden, vorhersagen.
Challenges and Opportunities in Electrocatalytic CO2Reduction to Chemicals and Fuels
Authors: She Xiaojie , Wang Yifei , Xu Hui , Chi Edman Tsang Shik , Ping Lau Shu 
Published: August 2022

AbstractThe global temperature increase must be limited to below 1.5 °C to alleviate the worst effects of climate change. Electrocatalytic CO2reduction (ECO2R) to generate chemicals and feedstocks is considered one of the most promising technologies to cut CO2emission at an industrial level. However, despite decades of studies, advances at the laboratory scale have not yet led to high industrial deployment rates. This Review discusses practical challenges in the industrial chain that hamper the scaling‐up deployment of the ECO2R technology. Faradaic efficiencies (FEs) of about 100 % and current densities above 200 mA cm−2have been achieved for the ECO2R to CO/HCOOH, and the stability of the electrolysis system has been prolonged to 2000 h. For ECO2R to C2H4, the maximum FE is over 80 %, and the highest current density has reached the A cm−2level. Thus, it is believed that ECO2R may have reached the stage for scale‐up. We aim to provide insights that can accelerate the development of the ECO2R technology.
Fiber‐spinning Asymmetric Assembly for Janus‐structured Bifunctional Nanofiber Films towards All‐Weather Smart Textile
Authors: Xie An‐Quan , Zhu Liangliang , Liang Yunzheng , Mao Jian , Liu Yijiang , Chen Su 
Published: August 2022

AbstractGiven health threat by global warming and increased energy consumption in regulating body temperature, it is an urgent need to construct smart temperature‐regulating materials. Herein, a novel fiber‐spinning asymmetric chemical assembly (FACA) method is proposed to construct nanofiber materials with asymmetric photothermal properties. The silver nanowires (AgNWs) and poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) with opposite thermal radiation are assembled on reduced graphene oxide (rGO) film, imparting AgNW/rGO/PVDF‐HFP film with Janus structure that can realize the AgNWs side consistently keeps temperature of ca. 11 °C lower than the side of PVDF‐HFP nanofiber regardless of the irradiation directions under 1 sun, suggesting the adjustable photothermal regulation. Such photothermally selective hybrid nanofiber film provides great potential as fabrics to achieve all‐weather smart clothes, promoting controllable and comprehensive utilization of solar energy.
Alterations of Gut Microbiome, Metabolome, and Lipidome in Takayasu Arteritis
Authors: Fan Luyun , Chen Junru , Pan Lili , Xin Xiaohong , Geng Bin , Yang Lirui , Wang Qian , Ma Wenjun , Lou Ying , Bian Jin , Cui Xiao , Li Jing , Wang Lu , Chen Zhenzhen , Wang Wenjie , Cui Changting , Li Shuangyue , Gao Qiannan , Song Qirui , Deng Yue , Fan Jiali , Yu Jiachen , Zhang Huimin , Li Yafeng , Cai Jun 
Published: August 2022

ObjectiveMounting evidence has linked microbiome and metabolome to systemic autoimmunity and cardiovascular diseases (CVDs). Takayasu arteritis (TAK) is a rare disease that shares features of immune‐related inflammatory diseases and CVDs, about which there is relatively limited information. This study was undertaken to characterize gut microbial dysbiosis and its crosstalk with phenotypes in TAK.MethodsTo address the discriminatory signatures, we performed shotgun sequencing of fecal metagenome across a discovery cohort (n = 97) and an independent validation cohort (n = 75) including TAK patients, healthy controls, and controls with Behçet's disease (BD). Interrogation of untargeted metabolomics and lipidomics profiling of plasma and fecal samples were also used to refine features mediating associations between microorganisms and TAK phenotypes.ResultsA combined model of bacterial species, including unclassified Escherichia, Veillonella parvula, Streptococcus parasanguinis, Dorea formicigenerans, Bifidobacterium adolescentis, Lachnospiraceae bacterium 7 1 58FAA, Escherichia coli, Streptococcus salivarius, Klebsiella pneumoniae, Bifidobacterium longum, and Lachnospiraceae Bacterium 5 1 63FAA, distinguished TAK patients from controls with areas under the curve (AUCs) of 87.8%, 85.9%, 81.1%, and 71.1% in training, test, and validation sets including healthy or BD controls, respectively. Diagnostic species were directly or indirectly (via metabolites or lipids) correlated with TAK phenotypes of vascular involvement, inflammation, discharge medication, and prognosis. External validation against publicly metagenomic studies (n = 184) on hypertension, atrial fibrillation, and healthy controls, confirmed the diagnostic accuracy of the model for TAK.ConclusionThis study first identifies the discriminatory gut microbes in TAK. Dysbiotic microbes are also linked to TAK phenotypes directly or indirectly via metabolic and lipid modules. Further explorations of the microbiome–metagenome interface in TAK subtype prediction and pathogenesis are suggested.
Risk of Arrhythmia Among New Users of Hydroxychloroquine in Rheumatoid Arthritis and Systemic Lupus Erythematosus: A Population‐Based Study
Authors: Hoque M. Rashedul , Lu Leo , Daftarian Narsis , Esdaile John M. , Xie Hui , Aviña‐Zubieta J. Antonio 
Published: August 2022

ObjectivesWe assessed the association between hydroxychloroquine (HCQ) initiation and risk of arrhythmia among patients with incident rheumatoid arthritis (RA) or with incident systemic lupus erythematosus (SLE).MethodsAll patients with incident RA or SLE and no arrhythmic events, not receiving antiarrhythmic medications, and not receiving HCQ prior to the index date of disease in British Columbia, Canada, between January 1996 and December 2014 were identified from administrative databases. We identified patients who were dispensed HCQ prescriptions (HCQ initiators) or were not dispensed HCQ prescriptions (HCQ noninitiators) during each study year; groups were matched 1:1 by propensity scores using baseline confounders on demographics, comorbidities, medications, and health care utilization. Outcomes were any new arrhythmias, atrial fibrillation, abnormal electrocardiograms, including long QT syndrome and conduction disorder, and other unspecified arrhythmias during follow‐up. We used cause‐specific Cox proportional hazards models with death as a competing event to assess the association between HCQ initiation and the outcomes.ResultsWe identified 11,518 propensity score–matched patients with RA or SLE in each group. Over the mean follow‐up of 8 years, there were 1,610 and 1,646 incident arrhythmias in the HCQ initiator group and the noninitiator group, respectively, with crude incidence rates of arrhythmia of 17.5 and 18.1 in 1,000 persons per year, respectively. The adjusted cause‐specific hazard ratio (cHR) for patients who received HCQ was 0.96 (95% confidence interval [95% CI] 0.89–1.03) compared with HCQ noninitiators, and the cHRs for patients who took HCQ and had arrhythmia subtypes of atrial fibrillation, abnormal electrocardiograms, and other unspecified arrhythmias were 0.93 (95% CI 0.83–1.04), 0.98 (95% CI 0.87–1.11), and 0.95 (95% CI 0.84–1.07), respectively.ConclusionRisk of any type of arrhythmia was not increased among new users of HCQ.
Enhanced Electrochemiluminescence of A Macrocyclic Tetradentate Chelate Pt(II) Molecule through Its Collisional Interactions with the Electrode
Authors: He Shuijian , Wang Xiang , Xiang Guiming , Lac Kevin , Wang Changshui , Wang Suning , Ding Zhifeng 
Published: August 2022

AbstractA macrocyclic tetradentate chelate Pt(II) molecule (Pt1) served as an excellent luminophore in electrochemiluminescence (ECL) processes. The blue ECL of Pt1/S2O82− coreactant system in N,N’‐dimethylformamide was found to be 46 times higher than that of the Ru(bpy)2+/S2O82− system or 30 times higher than that of the 9,10‐diphenylanthracene/S2O82− system. The unprecedented high ECL quantum efficiencies were caused by the cyclic generation of monomer excited states through collisional interactions of Pt1 molecules with the electrode at an elevated frequency. The ECL is tunable from bright blue to pure white by simply changing the solvent from N,N’‐dimethylformamide to dichloromethane. The white ECL of Pt(II) molecule was reported for the first time and the mechanism was proposed to be the simultaneous emissions from the monomer excited state (blue) and excimer (red).
Survival prediction by Bayesian network modeling for pseudomyxoma peritonei after cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy
Authors: Zhao Xin , Li Xinbao , Lin Yulin , Ma Ru , Zhang Ying , Xu Dazhao , Li Yan 
Published: August 2022

AbstractObjectivesTo establish a survival prognostic model for pseudomyxoma peritonei (PMP) treated with cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) based on Bayesian network (BN).Methods453 PMP patients were included from the database at our center. The dataset was divided into a training set to establish BN model and a testing set to perform internal validation at a ratio of 8:2. From the training set, univariate and multivariate analyses were performed to identify independent prognostic factors for BN model construction. The confusion matrix, receiver operating characteristic (ROC) curve and the area under curve (AUC) were used to evaluate the performance of the BN model.ResultsThe univariate and multivariate analyses identified 7 independent prognostic factors: gender, previous operation history, histological grading, lymphatic metastasis, peritoneal cancer index, completeness of cytoreduction and splenectomy (all p < 0.05). Based on independent factors, the BN model of training set was established. After internal validation, the accuracy and AUC of the BN model were 70.3% and 73.5%, respectively.ConclusionThe BN model provides a reasonable level of predictive performance for PMP patients undergoing CRS + HIPEC.
Valeridoids G – Q, Eleven seco‐Iridoids from Valeriana jatamansi and Their Bioactivites
Authors: Quan Li‐Qiu , Wang Yun , Tang Jian‐Xian , Zhou Yan , Liao Cai‐Cen , Liu Dan , Zhao Xu‐Dong , Li Rong‐Tao , Li Hong‐Mei 
Published: August 2022

AbstractEleven new seco‐iridoids, valeridoids G‐Q (1–6 and 8–12), along with four known products, 9‐epi‐valtral C (7), desacylbaldrinal (13), 11‐methoxyviburtinal (14) and baldrinal (15), were obtained from Valeriana jatamansi. Among them, the new compounds were identified by their NMR, HR‐ESI‐MS spectroscopic data and ECD calculation. Moreover, valeridoid N and O were a pair of C3 epimers, whose ether bonds between C‐1 and C‐3 opened, and new ether bonds formed between C‐3 and C‐6. Valeridoid Q belonged to the C‐1 degradation of seco‐iridoids. As a result, 9‐epi‐valtral C displayed significant inhibition on Streptococcus agalactiae, Staphylococcus aureus, Staphylococcus argenteus, Shigella flexneri and Klebsiella pneumoniae, and valeridoid Q exhibited the most significant inhibition against Salmonella enteritidis. 9‐Epi‐valtral C and baldrinal selectively inhibited the growth of human glioma stem cells. Valeridoid Q exhibited significant anti‐influenza activity, while valeridoid O inhibited nitric oxide production.
SARS‐CoV‐2 Papain‐Like Protease: Structure, Function and Inhibition
Authors: Ullrich Sven , Nitsche Christoph 
Published: August 2022

AbstractEmerging variants of SARS‐CoV‐2 and potential novel epidemic coronaviruses underline the importance of investigating various viral proteins as potential drug targets. The papain‐like protease of coronaviruses has been less explored than other viral proteins; however, its substantive role in viral replication and impact on the host immune response make it a suitable target to study. This review article focuses on the structure and function of the papain‐like protease (PLpro) of SARS‐CoV‐2, including variants of concern, and compares it to those of other coronaviruses, such as SARS‐CoV‐1 and MERS‐CoV. The protease's recognition motif is mirrored in ubiquitin and ISG15, which are involved in the antiviral immune response. Inhibitors, including GRL0617 derivatives, and their prospects as potential future antiviral agents are also discussed.
Towards Non‐stick Silk: Tuning the Hydrophobicity of Silk Fibroin Protein
Authors: Fountain Julia N. , Hawker Morgan J. , Hartle Lauren , Wu Junqi , Montanari Vittorio , Sahoo Jugal Kishore , Davis Luke M. , Kaplan David L. , Kumar Krishna 
Published: August 2022

AbstractSilk fibroin protein is a biomaterial with excellent biocompatibility and low immunogenicity. These properties have catapulted the material as a leader for extensive use in stents, catheters, and wound dressings. Modulation of hydrophobicity of silk fibroin protein to further expand the scope and utility however has been elusive. We report that installing perfluorocarbon chains on the surface of silk fibroin transforms this water‐soluble protein into a remarkably hydrophobic polymer that can be solvent‐cast. A clear relationship emerged between fluorine content of the modified silk and film hydrophobicity. Water contact angles of the most decorated silk fibroin protein exceeded that of Teflon®. We further show that water uptake in prefabricated silk bars is dramatically reduced, extending their lifetimes, and maintaining mechanical integrity. These results highlight the power of chemistry under moderate conditions to install unnatural groups onto the silk fibroin surface and will enable further exploration into applications of this versatile biomaterial.
Extending the Structure‐Activity Relationship of Disorazole C1: Exchanging the Oxazole Ring by Thiazole and Influence of Chiral Centers within the Disorazole Core on Cytotoxicity
Authors: Lizzadro Luca , Spieß Oliver , Collisi Wera , Stadler Marc , Schinzer Dieter 
Published: August 2022

AbstractThe synthesis of novel disorazole C1 analogues is described and their biological activity as cytotoxic compounds is reported. Based on our convergent entry to the disorazole core we present a flexible and robust strategy to construct a variety of interesting new analogues. In particular, two regions of the molecules were examined for structural modification: 1. Replacement of the heterocyclic moiety by an exchange of the oxazole ring by a thiazole; and 2. Evaluation of the influence of the absolute configuration of the chiral centers of the molecule. Predicated on our flexible strategy we were able to construct all analogues in an efficient way and could perform an exciting SAR (structure‐activity‐relationship) study to obtain insight in the cytotoxic activity influenced by the chiral centers of the disorazole core.
Leishmania amazonensis from distinct clinical forms/hosts has polymorphisms in Lipophosphoglycans, displays variations in immunomodulatory properties and, susceptibility to antileishmanial drugs
Authors: Rêgo Felipe D. , Cardoso Camila d. A. , Moreira Paulo Otávio L. , Nogueira Paula M. , Araújo Márcio S. , Borges Valéria Matos , Laurenti Márcia D. , Bartholomeu Daniella C. , Reis Alexandre B. , Monte‐Neto Rubens L. d. , Soares Rodrigo P. 
Published: August 2022

AbstractLipophosphoglycan (LPG), the major Leishmania glycoconjugate, induces pro‐inflammatory/immunosuppressive innate immune responses. Here, we evaluated functional/biochemical LPG properties from six Leishmania amazonensis strains from different hosts/clinical forms. LPGs from three strains (GV02, BA276, and LV79) had higher pro‐inflammatory profiles for most of the mediators, including tumor necrosis factor alpha and interleukin 6. For this reason, glycoconjugates from all strains were biochemically characterized and had polymorphisms in their repeat units. They consisted of three types: type I, repeat units devoid of side chains; type II, containing galactosylated side chains; and type III, containing glucosylated side chains. No relationship was observed between LPG type and the pro‐inflammatory properties. Finally, to evaluate the susceptibility against antileishmanial agents, two strains with high (GV02, BA276) and one with low (BA336) pro‐inflammatory activity were selected for chemotherapeutic tests in THP‐1 cells. All analyzed strains were susceptible to amphotericin B (AmB) but displayed various responses against miltefosine (MIL) and glucantime (GLU). The GV02 strain (canine visceral leishmaniasis) had the highest IC50 for MIL (3.34 μM), whereas diffuse leishmaniasis strains (BA276 and BA336) had a higher IC50 for GLU (6.87–12.19 mM). The highest IC50 against MIL shown by the GV02 strain has an impact on clinical management. Miltefosine is the only drug approved for dog treatment in Brazil. Further studies into drug susceptibility of L. amazonensis strains are warranted, especially in areas where dog infection by this species overlaps with those caused by Leishmania infantum.