bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arthpyrone L, a New Pyridone Alkaloid from a Deep‐Sea Arthrinium sp., Inhibits Proliferation of MG63 Osteosarcoma Cells by Inducing G0/G1 Arrest and Apoptosis
Authors: Zhang Yuying , Li Mengru , Zhang Qianqian , Wang Zhaoyang , Li Xiuxiu , Bao Jie , Zhang Hua 
Published: January 2021

AbstractFractionation of the ethanol extract of a marine fungus, Arthrinium sp., afforded a new pyridone alkaloid (arthpyrone L (1)), the structure with absolute configuration of which was established by comprehensive spectroscopic analyses. In vitro cell viability assays revealed that compound 1 showed antiproliferative effects toward human A549 (lung), MG63, U2OS (bone), MCF‐7 and MDA‐MB‐231 (breast) cancer cells. MG63 cell lines were chosen for further biological evaluations and presented apoptosis and cell cycle arrest (G0/G1 phase) upon treatment of 1. Subsequent mechanism studies demonstrated that the growth inhibition of 1 against MG63 cells was via activation of caspase‐modulated apoptotic pathway and inhibition of PI3K/Akt pathway.
Bioactive Phytochemicals and Antioxidant Capacity of Wheatgrass Treated with Salicylic Acid under Organic Soil Cultivation
Authors: Islam Mohammad Zahirul , Park Buem‐Jun , Lee Young‐Tack 
Published: January 2021

AbstractThis study was undertaken to determine the influence of salicylic acid (SA) on the bioactive phytochemicals and antioxidant capacity of wheatgrass extract in the organic growing medium. Wheatgrass was cultivated in SA‐enriched organic growing medium, obtained from acetylsalicylic acid (aspirin) of various concentrations (0 [control], 0.25, 0.50, 1.00, and 2.00 mM) in a plant growth chamber by controlling atmosphere (20/15 °C, day/night), light (14/10 h, light/dark; light intensity 150 μmol m−2 s−1, using quantum dot light‐emitting diodes), and atmospheric moisture (60 %) for 10 d. The 0.25 mM SA‐treatment showed the highest impact on germination rate, wheatgrass length, weight, yield, and chlorophyll content. Levels of bioactive phytochemicals, mainly phenolic compounds, flavonoids, β‐carotene, and vitamin C, were the highest in the 1.00 mM SA‐treated wheatgrass extract. The DPPH radical and nitrite‐scavenging capacities were the highest in the 1.00 mM SA‐treated wheatgrass extract. The 0.50 mM SA‐treated wheatgrass extract showed the highest superoxide dismutase‐like capacity, whereas the 2.00 mM SA‐treated wheatgrass extract showed the highest anthocyanin content and ABTS radical‐scavenging capacity. Therefore, it might be suggested that the appropriate levels of SA‐treatment were between 0.5 and 1.0 mM to enhance the bioactive phytochemicals and antioxidant capacity of wheatgrass.
Phosphonic Analogs of Alanine as Acylpeptide Hydrolase Inhibitors
Authors: Walczak Maciej , Chryplewicz Agnieszka , Olewińska Sandra , Psurski Mateusz , Winiarski Łukasz , Torzyk Karolina , Oleksyszyn Józef , Sieńczyk Marcin 
Published: January 2021

AbstractAcylpeptide hydrolase is a serine protease, which, together with prolyl oligopeptidase, dipeptidyl peptidase IV and oligopeptidase B, belongs to the prolyl oligopeptidase family. Its primary function is associated with the removal of N‐acetylated amino acid residues from proteins and peptides. Although the N‐acylation occurs in 50–90 % of eukaryotic proteins, the precise functions of this modification remains unclear. Recent findings have indicated that acylpeptide hydrolase participates in various events including oxidized proteins degradation, amyloid β‐peptide cleavage, and response to DNA damage. Considering the protein degradation cycle cross‐talk between acylpeptide hydrolase and proteasome, inhibition of the first enzyme resulted in down‐regulation of the ubiquitin‐proteasome system and induction of cancer cell apoptosis. Acylpeptide hydrolase has been proposed as an interesting target for the development of new potential anticancer agents. Here, we present the synthesis of simple derivatives of (1‐aminoethyl)phosphonic acid diaryl esters, phosphonic analogs of alanine diversified at the N‐terminus and ester rings, as inhibitors of acylpeptide hydrolase and discuss the ability of the title compounds to induce apoptosis of U937 and MV‐4‐11 tumor cell lines.
RNA‐Cleaving DNA Thresholder Controlled by Concentrations of miRNA Cancer Marker
Authors: Gomes de Oliveira Andrey Giovanni , Dubovichenko Mikhail V. , ElDeeb Ahmed A. , Wanjohi Joseph , Zablotskaya Sofia , Kolpashchikov Dmitry M. 
Published: January 2021

AbstractOligonucleotide gene therapy (OGT) agents suppress specific mRNAs in cells and thus reduce the expression of targeted genes. The ability to unambiguously distinguish cancer from healthy cells can solve the low selectivity problem of OGT agents. Cancer RNA markers are expressed in both healthy and cancer cells with a higher expression level in cancer cells. We have designed a DNA‐based construct, named DNA thresholder (DTh) that cleaves targeted RNA only at high concentrations of cancer marker RNA and demonstrates low cleavage activity at low marker concentrations. The RNA‐cleaving activity can be adjusted within one order of magnitude of the cancer marker RNA concentration by simply redesigning DTh. Importantly, DTh recognizes cancer marker RNA, while cleaving targeted RNA; this offers a possibility to suppress vital genes exclusively in cancer cells, thus triggering their death. DTh is a prototype of computation‐inspired molecular device for controlling gene expression and cancer treatment.
Sirtuin 1 promotes autophagy and proliferation of endometrial cancer cells by reducing acetylation level of LC3
Authors: Huang Shuai , Li Ye , Sheng Guihua , Meng Qingwei , Hu Qian , Gao Xuexiao , Shang Zhiyuan , Lv Qiubo 
Published: January 2021

AbstractEndometrial cancer (EC) constitutes a common female genital tract tumor with a rising incidence rate. Sirtuin 1 (SIRT1) is a member of histone deacetylase, which extensively participates in the progression of aging, cell death, and tumorigenesis. This study explored the effect of SIRT1‐mediated LC3 acetylation on autophagy and proliferation of EC cells. SIRT1 expression in EC tissues and adjacent tissues, EC cell lines and normal human epithelial cells was detected. SIRT1 expression was elevated in EC cell lines and tissues. Knockdown of SIRT1 inhibited proliferation, migration, and invasion of EC cells. Then, EC cells were starved in serum‐free medium, and levels of autophagy‐related proteins were detected. Starvation induced autophagy of EC cells. The starvation‐treated EC cells showed an increased SIRT1 expression, a decreased LC3 acetylation level and an increased autophagy level. The proliferation and autophagy of EC cells under different treatments were evaluated. In EC cells transfected with overexpressing SIRT1, LC3 acetylation was inhibited and cell proliferation was promoted. Moreover, overexpressing SIRT1 facilitated growth and autophagy of transplanted tumors in nude mice. In conclusion, SIRT1 promoted autophagy and proliferation of EC cells by reducing acetylation level of LC3.
Development and validation of a prediction model for angiographic perforation during chronic total occlusion percutaneous coronary intervention: OPEN‐CLEAN perforation score
Authors: Hirai Taishi , Grantham James Aaron , Sapontis James , Nicholson William J. , Lombardi William , Karmpaliotis Dimitri , Moses Jeffrey , Nugent Karen , Gosch Kensey L. , Salisbury Adam C. ,   The OPEN CTO Study Group
Published: January 2021

AbstractBackgroundPerforation is the most frequent complication of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) and is associated with adverse events including mortality.MethodsAmong 1,000 consecutive patients enrolled in 12 center prospective CTO PCI study (OPEN CTO), all perforations were reviewed by the angiographic core‐lab. Eighty‐nine patients (8.9%) with angiographic perforation were compared to 911 patients without perforation. We sought to describe the clinical and angiographic predictors of angiographic perforation during CTO PCI and develop a risk prediction model.ResultsAmong eight clinically important candidate variables, independent risk factors for perforation included prior CABG (OR 2.0 [95% CI, 1.2–3.3], p < .01), occlusion length (OR 1.2 per 10 mm increase [95% CI, 1.1–1.3], p < .01), ejection fraction (OR 1.2 per 10% decrease [95% CI, 1.1–1.5], p < .01), age (OR 1.3 per 5 year increase [95%CI, 1.1–1.5], p < .01), and heavy calcification (OR 1.7 [95% CI, 1.0–2.7], p = .04). Three other potential candidate variables, glomerular filtration rate, proximal cap ambiguity, and target vessel, were not independently associated with perforation. The model was internally validated using bootstrapping methods. From the full model, a simplified perforation prediction score (OPEN‐CLEAN score: CABG, Length [occlusion], EF < 50%, Age, CalcificatioN) was developed, which discriminated the risk of angiographic perforation well (c‐statistics = 0.75) and demonstrated good calibration.ConclusionThis simple 5‐variable prediction score may help CTO operators to risk‐stratify patients for angiographic perforation using variables available prior to CTO PCI procedures.
Diagnosis of maternal Hodgkin lymphoma following abnormal findings at noninvasive prenatal screening test (NIPT): Report of two cases
Authors: Castellino Alessia , Elba Simona , Sorasio Roberto , Castellino Claudia , Bonferroni Margherita , Grasso Mariella , Grosso Enrico , Giacchello Rosalba , Signorile Anna Franca , Celeghini Ivana , Mattei Daniele , Mordini Nicola , Foglietta Myriam , Masturzo Bianca , Priotto Roberto , Zonta Andrea , Rapezzi Davide , Massaia Massimo 
Published: January 2021

AbstractAbnormal NIPT results, contrasting with normal fetus development, could disclose maternal malignancy, and this possibility should always be explained during pretest counseling. In this case, a complete diagnostic assessment is recommended and should be managed by a multidisciplinary team to define the best timing for diagnostic procedures, delivery, and treatment.
COVID‐19 pneumonia in a pediatric sickle cell patient requiring red blood cell exchange
Authors: Walker Shannon C. , Murphy Meghan L. , Hendricks Hope , Dulek Daniel E. , Volanakis Emmanuel J. , Borinstein Scott C. 
Published: January 2021

AbstractPatients with sickle cell disease are already at high risk for respiratory complications, which SARS‐CoV‐2 can rapidly worsen. The case emphasizes the importance of efficiently maximizing standard therapies in sickle cell patients with COVID‐19.
Floating aortic thrombus with celiac artery embolus presenting with chronic epigastric and right upper quadrant pain: A case report
Authors: Jahanshahi Fatemeh , Kalantar Motamedi Alireza 
Published: January 2021

AbstractArterial occlusion may be the cause of chronic pain, and vascular diagnostic procedures should be a part of the workup in patients with unexplained chronic visceral pain.
Influence of the MnO2 Phase on Oxygen Evolution Reaction Performance for Low‐Loading Iridium Electrocatalysts
Authors: Wang Zheyuan , Gao Wenluan , Xu Qingli , Ren Xiaona , Xu Shuang , Zhu Shuaikang , Niu Xiaopo , Li Xiaoxue , Zhao Rong , Han Yunxi , Li Guozhu , Wang Qingfa 
Published: January 2021

AbstractDeveloping high‐performance, low‐loading, Ir‐based electrocatalysts for the oxygen evolution reaction (OER) in acidic media is still a great challenge. Herein, we fabricated an iridium manganese catalyst with only 5 % iridium. The influence of the manganese dioxide phase states (α‐, β‐, γ‐ and δ‐MnO2) on the OER performance of IrO2/MnO2 catalysts was investigated. α‐MnO2, as the substrate, can generate smaller iridium particles and more high‐valence‐state iridium to promote OER performance. Therefore, the 5 % IrO2/α‐MnO2 electrocatalyst exhibits excellent electrocatalytic OER performance with a high mass activity of 216.67 A/gIr and 655.33 A/gIr at 1.53 V in acidic and alkaline media, respectively, significantly outperforming commercial IrO2.
Modulating Hydroxyl‐Rich Interfaces on Nickel–Copper Double Hydroxide Nanotyres to Pre‐activate Alkaline Ammonia Oxidation Reactivity
Authors: Yang Anzhou , Wang Jingchun , Su Keying , Lei Wu , Qiu Xiaoyu , Tang Yawen 
Published: January 2021

AbstractThe surface hydroxyl groups of NixCu1−x(OH)2 play a crucial role in governing their conversion efficiency into NixCu1−xOx(OH)2−x during the electro‐chemical pre‐activation process, thus affecting the integral ammonia oxidation reaction (AOR) reactivity. Herein, the rational design of hierarchical porous NiCu double hydroxide nanotyres (NiCu DHTs) was reported for the first time by considering hydroxyl‐rich interfaces to promote pre‐activation efficiency and intrinsic structural superiority (i.e., annulus, porosity) to accelerate AOR kinetics. A systematic investigation of the structure–function relationship was conducted by manipulating a series of NiCu DHs with tunable intercalations and morphologies. Remarkably, the NiCu DHTs exhibit superior AOR activity (onset potential of 1.31 V with 7.52 mA cm−2 at 1.5 V) and high ammonia sensitivity (detection limit of 9 μm), manifesting one of the best non‐noble metal AOR electrocatalysts and electro‐analytical electrodetectors. This work deepens the understanding of the crucial role of surface hydroxyl groups on determining the catalytic performance in alkaline medium.
Self‐Assembled Binaphthyl‐Bridged Amphiphilic AABB Phthalocyanines: Nanostructures for Efficient Antimicrobial Photodynamic Therapy
Authors: Revuelta‐Maza Miguel Ángel , de las Heras Elena , Agut Montserrat , Nonell Santi , Torres Tomás , de la Torre Gema 
Published: January 2021

AbstractHerein, the photodynamic activity of phthalocyanine (pc)‐assembled nanoparticles against bacterial strains is demonstrated. The photosensitizers (PS) studied in this work are two chiral ZnIIPcs (PS‐1 and PS‐2), with an AABB geometry (where A and B refer to differently substituted isoindole constituents). They contain differently functionalized, chiral binaphthyloxy‐linked A isoindole units, which determine the hydrophobicity of the system, and cationic methyl pyridinium moieties in the other two isoindoles to embody hydrophilicity. Both compounds have the ability to self‐assemble into nanoparticles in aqueous media and have proved efficient in the photo‐inactivation of Staphylococcus aureus and Escherichia coli, selected as models of Gram‐positive and Gram‐negative bacteria. The average size of the nanoparticles was determined by substitution at the binaphthyl core and, in turn, influences the toxicity of the PS. Thus, PS‐1, presenting a nonsubstituted binaphthyl core, forms larger nanoparticles with a larger cationic surface than the octyl‐functionalized PS‐2. Although both PSs present similar structure and photophysical features, the self‐assembled nanostructures of PS‐1 are more effective at killing both types of strain, showing an outstanding photo‐inactivation capacity with the Gram‐negative E. coli.
Cations and Anions of Dibenzo[a,e]pentalene and Reduction of a Dibenzo[a,e]pentalenophane
Authors: Hermann Mathias , Böttcher Tobias , Schorpp Marcel , Richert Sabine , Wassy Daniel , Krossing Ingo , Esser Birgit 
Published: January 2021

AbstractDibenzo[a,e]pentalene (DBP) is a non‐alternant conjugated hydrocarbon with antiaromatic character and ambipolar electrochemical behavior. Upon both reduction and oxidation, it becomes aromatic. We herein study the chemical oxidation and reduction of a planar DBP derivative and a bent DBP‐phane. The molecular structures of its planar dication, cation radical and anion radical in the solid state demonstrate the gained aromaticity through bond length equalization, which is supported by nucleus independent chemical shift‐calculations. EPR spectra on the cation radical confirm the spin delocalization over the DBP framework. A similar delocalization was not possible in the reduced bent DBP‐phane, which stabilized itself by proton abstraction from a solvent molecule upon reduction. This is the first report on structures of a DBP cation radical and dication in the solid state and of a reduced bent DBP derivative. Our study provides valuable insight into the charged species of DBP for its application as semiconductor.
The Effect of Auxiliary Nitrogenated Linkers on the Design of New Cadmium‐Based Coordination Polymers as Sensors for the Detection of Explosive Materials
Authors: Aguirre‐Díaz Lina M. , Echeverri Marcelo , Paredes‐Gil Katherine , Snejko Natalia , Gómez‐Lor Berta , Gutiérrez‐Puebla Enrique , Monge M. Ángeles 
Published: January 2021

AbstractThree new cadmium‐based coordination polymers, denoted [Cd(hfipbb)(4,4’‐bipy)] (CdPF‐1), [Cd(hfipbb)(2,2’‐bipy)] (CdPF‐2), and [Cd(hfipbb)(1,10‐phen)] (CdPF‐3), have been hydrothermally synthesized by using the well‐known V‐shaped organic linker 4,4’‐(hexafluoroisopropylidene)bis(benzoic acid) (H2hfipbb), together with different nitrogenated auxiliary linkers. Considering the d10 configuration of the transition metal selected, the luminescent properties for these CdPF‐n materials were explored, finding that materials CdPF‐2 and CdPF‐3 act as excellent sensors in the detection of explosive nitro aromatic compounds. The photoluminescence properties of CdPF‐2 and CdPF‐3 revealed that significant and sensitive fluorescence quenching was observed toward NP (nitrophenol) for CdPF‐2 and PA (picric acid) for CdPF‐3 in MeOH suspensions.
Proton Switch in the Secondary Coordination Sphere to Control Catalytic Events at the Metal Center: Biomimetic Oxo Transfer Chemistry of Nickel Amidate Complex
Authors: Kim Soohyung , Jeong Ha Young , Kim Seonghan , Kim Hongsik , Lee Sojeong , Cho Jaeheung , Kim Cheal , Lee Dongwhan 
Published: January 2021

AbstractHigh‐valent metal‐oxo species are key intermediates for the oxygen atom transfer step in the catalytic cycles of many metalloenzymes. While the redox‐active metal centers of such enzymes are typically supported by anionic amino acid side chains or porphyrin rings, peptide backbones might function as strong electron‐donating ligands to stabilize high oxidation states. To test the feasibility of this idea in synthetic settings, we have prepared a nickel(II) complex of new amido multidentate ligand. The mononuclear nickel complex of this N5 ligand catalyzes epoxidation reactions of a wide range of olefins by using mCPBA as a terminal oxidant. Notably, a remarkably high catalytic efficiency and selectivity were observed for terminal olefin substrates. We found that protonation of the secondary coordination sphere serves as the entry point to the catalytic cycle, in which high‐valent nickel species is subsequently formed to carry out oxo‐transfer reactions. A conceptually parallel process might allow metalloenzymes to control the catalytic cycle in the primary coordination sphere by using proton switch in the secondary coordination sphere.
Real‐Time Analysis of Polyphenol–Protein Interactions by Surface Plasmon Resonance Using Surface‐Bound Polyphenols
Authors: Delannoy López Daniela Mélanie , Tran Dong Tien , Viault Guillaume , Dairi Sofiane , Peixoto Philippe Alexandre , Capello Yoan , Minder Laëtitia , Pouységu Laurent , Génot Elisabeth , Di Primo Carmelo , Deffieux Denis , Quideau Stéphane 
Published: January 2021

AbstractA selection of bioactive polyphenols of different structural classes, such as the ellagitannins vescalagin and vescalin, the flavanoids catechin, epicatechin, epigallocatechin gallate (EGCG), and procyanidin B2, and the stilbenoids resveratrol and piceatannol, were chemically modified to bear a biotin unit for enabling their immobilization on streptavidin‐coated sensor chips. These sensor chips were used to evaluate in real time by surface plasmon resonance (SPR) the interactions of three different surface‐bound polyphenolic ligands per sensor chip with various protein analytes, including human DNA topoisomerase IIα, flavonoid leucoanthocyanidin dioxygenase, B‐cell lymphoma 2 apoptosis regulator protein, and bovine serum albumin. The types and levels of SPR responses unveiled major differences in the association, or lack thereof, and dissociation between a given protein analyte and different polyphenolic ligands. Thus, this multi‐analysis SPR technique is a valuable methodology to rapidly screen and qualitatively compare various polyphenol–protein interactions.
Computational Insights into Different Mechanisms for Ag‐, Cu‐, and Pd‐Catalyzed Cyclopropanation of Alkenes and Sulfonyl Hydrazones
Authors: Wu Yong , Cao Shanshan , Douair Iskander , Maron Laurent , Bi Xihe 
Published: January 2021

AbstractThe [2+1] cycloaddition reaction of a metal carbene with an alkene can produce important cyclopropane products for synthetic intermediates, materials, and pharmaceutical applications. However, this reaction is often accompanied by side reactions, such as coupling and self‐coupling, so that the yield of the cyclopropanation product of non‐silver transition‐metal carbenes and hindered alkenes is generally lower than 50 %. To solve this problem, the addition of a low concentration of diazo compound (decomposition of sulfonyl hydrazones) to alkenes catalyzed by either CuOAc or PdCl2 was studied, but side reactions could still not be avoided. Interestingly, however, the yield of cyclopropanation products for such hindered alkenes were as high as 99 % with AgOTf as a catalyst. To explain this unexpected phenomenon, reaction pathways have been computed for four different catalysts by using DFT. By combining the results of these calculations with those obtained experimentally, it can be concluded that the efficiency of the silver catalyst is due to the barrierless concerted cycloaddition step and the kinetic inhibition of side reactions by a high concentration of alkene.
C−N Axial Chiral Hypervalent Iodine Reagents: Catalytic Stereoselective α‐Oxytosylation of Ketones
Authors: Alharbi Haifa , Elsherbini Mohamed , Qurban Jihan , Wirth Thomas 
Published: January 2021

AbstractA simple synthesis of a library of novel C−N axially chiral iodoarenes is achieved in a three‐step synthesis from commercially available aniline derivatives. C−N axial chiral iodine reagents are rarely investigated in the hypervalent iodine arena. The potential of the novel chiral iodoarenes as organocatalysts for stereoselective oxidative transformations is assessed using the well explored, but challenging stereoselective α‐oxytosylation of ketones. All investigated reagents catalyse the stereoselective oxidation of propiophenone to the corresponding chiral α‐oxytosylated products with good stereochemical control. Using the optimised reaction conditions a wide range of products was obtained in generally good to excellent yields and with good enantioselectivities.
Small Figure‐Eight Luminophores: Double‐Twisted Tethered Cyclic Binaphthyls Boost Circularly Polarized Luminescence
Authors: Nojima Yuki , Hasegawa Masashi , Hara Nobuyuki , Imai Yoshitane , Mazaki Yasuhiro 
Published: January 2021

AbstractDouble‐twisted cyclic binaphthyls, in which two naphthalenes are tethered by ‐O(CH2)nO‐ linkage (n=1–3), have been synthesized. X‐ray analyses and DFT calculations revealed a tightly constrained stereogenic figure‐eight geometry. Tethering of two naphthalenes by short linkage forces a small dihedral angle, and the cyclic binaphthyls with short tether (n=1, 2) exhibit remarkable boosting of the glum value (1.0–1.6×10−2) in circularly polarized luminescence (CPL) and unusual glum/gabs ratios (0.93–1.3). These experimental high |glum| values are in accord with the results of excited state TD‐DFT calculations, which show transannular interactions and that consequent extensive delocalization occurs throughout the figure‐eight π‐core. As a result, the present figure‐eight luminophore promote the elongation of the magnetic transition dipole moment that results in significant increases in glum values.