bluuebunny/crossref_metadata_2025 huggingface dataset:
Polar Isotactic and Syndiotactic Polypropylenes by Organozirconium‐Catalyzed Masking‐Reagent‐Free Propylene and Amino–Olefin Copolymerization
Authors: Huang Minglu , Chen Jiazhen , Wang Binghao , Huang Wei , Chen Haibo , Gao Yanshan , Marks Tobin J.
Published: July 2020

Polar functionalized isotactic and syndiotactic polypropylenes (PPs) are synthesized by direct, masking‐reagent‐free propylene and amino–olefin (AO, CH2=CH(CH2)xNnPr2, x=2, 3, 6) copolymerizations using the activated precatalysts rac‐[Me2Si(indenyl)2]ZrMe2 and [Me2C(Cp)(fluorenyl)]ZrMe2, respectively. Polymerization activities at 25 °C are as high as 4208 and 535 kg/(mol h atm) with AO incorporation up to 4.0 mol % and 1.6 mol %, respectively. Remarkably, introducing the amino‐olefin comonomers significantly enhances stereoselection for both isotactic (mmmm: 59.5 %→91.0 %) and syndiotactic (rrrr: 66.3 %→81.3 %) products.
Suppressing Interfacial Charge Recombination in Electron‐Transport‐Layer‐Free Perovskite Solar Cells to Give an Efficiency Exceeding 21 %
Authors: Wu Wu‐Qiang , Liao Jin‐Feng , Zhong Jun‐Xing , Xu Yang‐Fan , Wang Lianzhou , Huang Jinsong
Published: July 2020

The performances of electron‐transport‐layer (ETL)‐free perovskite solar cells (PSCs) are still inferior to ETL‐containing devices. This is mainly due to severe interfacial charge recombination occurring at the transparent conducting oxide (TCO)/perovskite interface, where the photo‐injected electrons in the TCO can travel back to recombine with holes in the perovskite layer. Herein, we demonstrate for the first time that a non‐annealed, insulating, amorphous metal oxyhydroxide, atomic‐scale thin interlayer (ca. 3 nm) between the TCO and perovskite facilitates electron tunneling and suppresses the interfacial charge recombination. This largely reduced the interfacial charge recombination loss and achieved a record efficiency of 21.1 % for n‐i‐p structured ETL‐free PSCs, outperforming their ETL‐containing metal oxide counterparts (18.7 %), as well as narrowing the efficiency gap with high‐efficiency PSCs employing highly crystalline TiO2 ETLs.
Ammonia Oxidation Enhanced by Photopotential Generated by Plasmonic Excitation of a Bimetallic Electrocatalyst
Authors: Wang Jun , Heo Jaeyoung , Chen Changqiang , Wilson Andrew J. , Jain Prashant K.
Published: July 2020

We study how visible light influences the activity of an electrocatalyst composed of Au and Pt nanoparticles. The bimetallic composition imparts a dual functionality: the Pt component catalyzes the electrochemical oxidation of ammonia to liberate hydrogen and the Au component absorbs visible light by the excitation of localized surface plasmon resonances. Under visible‐light excitation, this catalyst exhibits enhanced electrochemical ammonia oxidation kinetics, outperforming previously reported electrochemical schemes. We trace the enhancement to a photochemical potential resulting from electron–hole carriers generated in the electrocatalyst by plasmonic excitation. The photopotential responsible for enhanced kinetics scales linearly with the light intensity—a general design principle for eliciting superlative photoelectrochemical performance from catalysts comprised of plasmonic metals or hybrids. We also determine a photochemical conversion coefficient.
PlatinER: A Highly Potent Anticancer Platinum(II) Complex that Induces Endoplasmic Reticulum Stress Driven Immunogenic Cell Death
Authors: Tham Max Jing Rui , Babak Maria V. , Ang Wee Han
Published: July 2020

Immunogenic cell death (ICD) is a rare immunostimulatory form of cell death that can improve the clinical outcomes of chemo‐immunotherapeutic combination regimens through the establishment of a long‐term cancer immunity. None of the clinically used DNA‐binding PtII complexes is considered a Type II ICD inducer. We generated a series of PtII‐carbene complexes by applying minor structural alterations to the scaffold of a Type II ICD inducer Pt‐NHC and compared their efficiency in triggering ICD‐related cellular responses and phagocytosis. We successfully identified PlatinER, a novel highly potent PtII candidate with superior ICD properties. Crucially, the magnitude of ICD‐associated phagocytosis induced upon exposure of cancer cells to Pt complexes was dependent on the levels of ER‐localized reactive oxygen species (ROS) generation, which underpins their mechanisms of action and provides a feasible approach for the design of more effective Type II ICD inducers.
Removal of Organic Micropollutants from Water by Macrocycle‐Containing Covalent Polymer Networks
Authors: Ji Xiaofan , Wang Hu , Wang Hongyu , Zhao Tian , Page Zachariah A. , Khashab Niveen M. , Sessler Jonathan L.
Published: July 2020

Access to clean drinking water is a recognized societal need that touches on the health and livelihood of millions of people worldwide. This is providing an incentive to develop new water‐treatment technologies. Traditional technologies, while widespread, are usually inefficient at removing organic pollutants from sewage or so‐called grey water. Macrocycle‐containing covalent polymer networks have begun to attract attention in the context of water treatment owing to the inherent stability provided by the polymer backbones and their ability to capture micropollutant guests as the result of tunable macrocycle‐based host–guest interactions. In this Minireview, we summarize recent advances (from 2016 to mid‐2020) involving the removal of organic micropollutants from water using macrocycle‐containing covalent polymer networks. An overview of future challenges within this subfield is also provided.
Surface Reconstruction of Ultrathin Palladium Nanosheets during Electrocatalytic CO2 Reduction
Authors: Zhao Yong , Tan Xin , Yang Wanfeng , Jia Chen , Chen Xianjue , Ren Wenhao , Smith Sean C. , Zhao Chuan
Published: July 2020

A surface reconstructing phenomenon is discovered on a defect‐rich ultrathin Pd nanosheet catalyst for aqueous CO2 electroreduction. The pristine nanosheets with dominant (111) facet sites are transformed into crumpled sheet‐like structures prevalent in electrocatalytically active (100) sites. The reconstruction increases the density of active sites and reduces the CO binding strength on Pd surfaces, remarkably promoting the CO2 reduction to CO. A high CO Faradaic efficiency of 93 % is achieved with a site‐specific activity of 6.6 mA cm−2 at a moderate overpotential of 590 mV on the reconstructed 50 nm Pd nanosheets. Experimental and theoretical studies suggest the CO intermediate as a key factor driving the structural transformation during CO2 reduction. This study highlights the dynamic nature of defective metal nanosheets under reaction conditions and suggests new opportunities in surface engineering of 2D metal nanostructures to tune their electrocatalytic performance.
Ferromagnetically Coupled S=1 Chains in Crystals of Verdazyl‐Nitronyl Nitroxide Diradicals
Authors: Tretyakov Evgeny V. , Zhivetyeva Svetlana I. , Petunin Pavel V. , Gorbunov Dmitry E. , Gritsan Nina P. , Bagryanskaya Irina Yu. , Bogomyakov Artem S. , Postnikov Pavel S. , Kazantsev Maxim S. , Trusova Marina E. , Shundrina Inna K. , Zaytseva Elena V. , Parkhomenko Dmitriy A. , Bagryanskaya Elena G. , Ovcharenko Victor I.
Published: July 2020

Thermally stable organic diradicals with a triplet ground state along with large singlet‐triplet energy gap have significant potential for advanced technological applications. A series of phenylene‐bridged diradicals with oxoverdazyl and nitronyl nitroxide units were synthesized via a palladium‐catalyzed cross‐coupling reaction of iodoverdazyls with a nitronyl nitroxide‐2‐ide gold(I) complex with high yields. The diradicals exhibit high stability and do not decompose in an inert atmosphere up to 180 °C. For the diradicals, both substantial AF (ΔEST≈−64 cm−1) and FM (ΔEST≥25 and 100 cm−1) intramolecular exchange interactions were observed. The sign of the exchange interaction is determined both by the bridging moiety (para‐ or meta‐phenylene) and by the type of oxoverdazyl block (C‐linked or N‐linked). Upon crystallization, diradicals with the triplet ground state form unique one‐dimensional exchange‐coupled chains with strong intra‐ and weak inter‐diradical ferromagnetic coupling.
Chemical Characterization of Sorbitan Tri‐Stearate Commercial Samples and Their Determination in Confectionery Fats by HPLC High‐Resolution Mass Spectrometry
Authors: Baiocchi Claudio , Magni Martina , Romaniello Francesco , Forte Emanuele , Fontana Mauro
Published: July 2020

Nominal sorbitan tristearate (E492) commercial samples are widely used generally as emulsifiers and particularly as anti‐bloom agents in confectionery products. In spite of this generalized use, their qualitative and quantitative evaluation is poorly documented in literature and the relative works go back to the last decades of last century. In the present work, a deep study by HPLC‐High Resolution Mass Spectrometry of qualitative composition of five E492 commercial samples was made up showing a very complex pattern of stearic and palmitic acid esters with the sorbitol anhydrides, sorbitan, and isosorbide. A clear distinction of sorbitan mono‐, di‐, tri‐, and tetra‐esters, of sorbitol penta‐ and hexa‐esters and isosorbide mono‐ and di‐esters was achieved. Contemporarily, difference in the qualitative pattern between E492 commercial samples coming from different suppliers was established. As a consequence, quantitative evaluation can be reliably obtained by using as calibration standard the same E492 present in real samples. The accuracy and recovery of the method were determined allowing in this way a reliable application to commercial confectionery products. The detailed knowledge of STS composition may be of great help to orient the synthesis conditions in order to modulate its properties as a function of various experimental necessities.
Clinical Issues—August 2020
Authors: Anderson Mary Alice
Published: July 2020

THIS MONTH

Pneumatic tourniquet education and documentation

Key words: pneumatic tourniquet, documentation, competency verification, tourniquet cuff.

Creating a safe environment for surgical patients with latex allergies or sensitivities

Key words: natural rubber latex, latex allergy, latex sensitivity, latex reaction, anaphylaxis.

Covering patients’ beards

Key words: facial hair, surgical site infection (SSI), beard, sterile field.

Informed consent requirements

Key words: informed consent, witness, legal representative, signature.

Promoting well‐being through mindfulness

Key words: conscious leadership, mindfulness, well‐being, work environment, positive focus.
A poly(L‐lactic acid) monofilament with high mechanical properties for application in biodegradable biliary stents
Authors: Tian Yuan , Zhang Jing , Cheng Jie , Wu Gensheng , Zhang Yi , Ni Zhonghua , Zhao Gutian
Published: July 2020

In this article, a poly(L‐lactic acid) (PLLA) monofilament with high mechanical properties which can be used to construct biodegradable biliary stents (BBS) is prepared. Compared with a commercial polydioxanone (PDO) suture, the PLLA monofilament has much higher Young's modulus. As a result, chronic outward force (COF) of the stent braided by PLLA monofilament is more than three times higher than that of the stent braided by PDO suture. Furthermore, by physicochemical indexes characterizations, it is acceptable that the PLLA monofilament has stable Young's modulus and higher elongation at break without brittle fracture risk during degradation in bile. In contrast, although PDO suture can also maintain Young's modulus well during degradation, its elongation at break is attenuated rapidly, which shows a high brittle fracture risk. These results indicate that PLLA monofilament is more suitable for constructing BBS with high COF, which are promising in treating more complex biliary strictures that need longer support time.
The crosslinking directing dynamic behavior of polymer latex under the investigation toward waterborne damping coatings
Authors: Li Yue , Guo Longhai , Ye Jun , He Lifan , Qiu Teng , Li Xiaoyu
Published: July 2020

Latex polymers with precisely designed dynamic mechanical behavior are the key for waterborne damping coatings, which are widely desired in noise and vibration reduction with additional environmental benefits. In this work, we synthesized series of polymer latexes with various crosslinking agents (CA) and network distributions through the control on emulsion polymerization processes. We have revealed that the variation on crosslinking can significantly direct the latex behavior under dynamic conditions as well as its films. The variables involve the CA composition, the functionality, the crosslinking manner, the hydrophilic‐hydrophobic feature as well as the feeding method. Although all the latex films showed the damping peaks locating in the range from −10 to 70°C, their damping behaviors were quite different. Suggested by the empirical parameters of LA and TA, the product from sequential monomer feeding method tended to give good extensional damping performance. Especially when the crosslinking of diacetone acrylamide (DAAM)/adipic dihydrazide was applied, there was a linear increase on LA with the increasing dosage of DAAM from 0 to 10 mmol in the final monomer addition batch. Meanwhile, good constrained layer damping is expected on the products from the power monomer feeding method with the maximum CA dosage shown below 7.5 mmol. The best TA was achieved when the CA of divinylbenzene was used in the dosage of 5 mmol. These results would be valuable to be referenced in the engineering on organic damping materials toward modern industrial and vehicles applications.
Iodine‐loaded poly(silicic acid) gellan nanocomposite mucoadhesive film for antibacterial application
Authors: Sharma Rashmi , Pahwa Rimpy , Ahuja Munish
Published: July 2020

Iodine‐loaded poly(silicic acid) gellan nanocomposite film was fabricated and evaluated for antibacterial properties. Poly(silicic acid) nanoparticles were synthesized by condensation of silicic acid under alkaline conditions in the presence of polyvinyl pyrrolidone, phosphate ions, and molecular iodine. The nanoparticles were incorporated into gellan dispersion to prepare gellan nanocomposite film using the solvent casting method. The nanocomposite films were characterized by Fourier transformed infrared spectroscopy, thermogravimetric analysis, and X‐ray diffraction studies. The results of characterization studies indicated improved thermal stability and an increase in the degree of crystallinity. The scanning electron micrographs and energy dispersive X‐ray spectrum confirmed the uniform dispersion of silica and iodine in the nanocomposite films. The analysis of physical and mechanical properties revealed the enhanced tensile strength, moisture resistance, and higher folding endurance of poly(silicic acid) gellan nanocomposite films as compared to gellan film. Further, the iodine‐loaded poly(silicic acid) gellan nanocomposite films showed good antibacterial activity against Staphylococcus aureus and Escherichia coli and effective mucoadhesive strength. The results indicate that iodine‐loaded poly(silicic acid) gellan nanocomposite mucoadhesive film can be used for potential antibacterial applications in pharmaceuticals.
Trifunctional quinoxaline‐based maleimide and its polymer alloys with benzoxazine: Synthesis, characterization, and properties
Authors: Wang Hui , Dayo Abdul Qadeer , Wang Jun , Wang Jun‐yi , Liu Wen‐bin
Published: July 2020

Novel quinoxaline‐based trismaleimide (2,3‐di[3‐maleimido]phenyl‐6‐ maleimidoquinoxaline, namely TQMI) and its polymer alloys with 3‐phenyl‐3,4‐dihydro‐2H‐1,3‐benzoxazine (P‐a) were successfully prepared and characterized. Differential scanning calorimetry investigation of TQMI exhibited distinct double exothermic peaks, which implied that the curing behavior of different type of maleimide group was discrepant. The curing temperature of P‐a/TQMI prepolymers was lower than that of both neat TQMI and P‐a monomer. The temperatures at 5% (T5) and 10% (T10) weight loss and the char yield (Yc) of cured TQMI at 800°C reached 513°C, 524°C, and 63.5%, respectively, which were much higher than the record of traditional 4,4′‐bismaleimideodiphenylmethane (BMDPM) resin as well as most of other reported bismaleimide resins. Moreover, the addition of TQMI enhanced thermal stability, glass transition temperature (Tg), and limiting oxygen index of benzoxazine resin dramatically. Attractively, the Tg value of P‐a/TQMI copolymer at 30 wt% TQMI loadings was approximately 20°C higher than that of P‐a/BMDPM copolymer owing to the bulky quinoxaline group.
Transparent, methacrylate‐based polymer networks with controlled crosslinker ductility
Authors: Masser Kevin A. , Orlicki Joshua A. , Napadensky Eugene , Taylor Terrence , Harris Doug
Published: July 2020

A series of transparent methacrylate‐based crosslinked polymer networks are prepared in which the crosslinker length is controlled as a means to investigate the effects of network ductility on mechanical and ballistic properties. In each network the optical clarity of pure poly(methyl methacrylate) (PMMA) is retained, as well as a low value of haze. Both the glass transition temperature (Tg) and the tensile modulus of the networks are highly tunable, with network values both above and well below that of pure PMMA or the pure crosslinker network. The ballistic performance is likewise affected, with performance values of up to 400% greater than neat PMMA. We examine the effects of the crosslinker molecular weight on the impact performance, finding that, in these systems, the molecular weight between crosslinks is not a driving factor for the impact performance, and this may broadly translate to polymer networks in general. We find that improvements in ballistic performance can be realized at low molecular weight between crosslinks, provided the crosslinking agent is of sufficient ductility.
Reciprocally convex approach for cooperative tracking control of general network systems with fixed/switching topologies
Authors: Li Yanzhou , Wu Yuanqing , He Shenghuang
Published: July 2020

The cooperative tracking problem of general network systems with fixed/switching topology having a directed spanning tree is investigated in this paper. A distributed sampled‐data controller is preferentially designed for each follower to track the independent leader. By using tools from input‐delay and a reciprocally convex approach, some sufficient conditions ensuring the purpose of tracking are derived. Theoretical analysis is then extended to the case that the topologies of network systems are time‐varying. It is demonstrated that the cooperative tracking problem for network systems can be solved under some sufficient conditions. Through the above investigation, the cooperative tracking problem of general network systems with fixed/switching topology is solved. The capabilities of the proposed control algorithm are finally verified on our experimental platform.
Upconversion process in BaY2F8:Yb3+,Ho3+ phosphor for optical thermometry
Authors: Nair Govind B. , Sharma Ashwini K. , Dhoble S.J. , Swart H.C.
Published: July 2020

A BaY2F8:Yb3+,Ho3+ phosphor was synthesized using a simple precipitation method. The temperature‐sensing properties of BaY2F8:Yb3+,Ho3+ phosphor were investigated using the fluorescence intensity ratio (FIR) of the thermally coupled energy levels (5F4 and 5S2) of Ho3+. Energy transitions 5F4→5I8 and 5S2→5I8 gave rise to emission peaks at 538 nm and 549 nm, respectively. The areas under these two emission peaks were used to calculate the FIR. Temperature‐dependent upconversion luminescence was recorded in the temperature range 303–623 K using a 980 nm laser excitation source. The results suggested that the BaY2F8:Yb3+, Ho3+ phosphor has the potential to be used as a non‐contact optical temperature sensor.
In vivo interpretation of model predicted inhibition in acrylate pathway engineered Lactococcus lactis
Authors: Balasubramanian Sowmiya , Chandrasekran Priyadharshini , Yesudhas Anitha J. R. , Ganapathyraman Padmapriya , Eiteman Mark A. , Subramanian Ramalingam
Published: July 2020

To maximize the productivity of engineered metabolic pathway, in silico model is an established means to provide features of enzyme reaction dynamics. In our previous study, Escherichia coli engineered with acrylate pathway yielded low propionic acid titer. To understand the bottleneck behind this low productivity, a kinetic model was developed that incorporates the enzymatic reactions of the acrylate pathway. The resulting model was capable of simulating the fluxes reported under in vitro studies with good agreement, suggesting repression of propionyl‐CoA transferase (Pct) by carboxylate metabolites as the main limiting factor for propionate production. Furthermore, the predicted flux control coefficients of the pathway enzymes under steady state conditions revealed that the control of flux is shared between Pct and lactoyl‐CoA dehydratase. Increase in lactate concentration showed gradual decrease in flux control coefficients of Pct that in turn confirmed the control exerted by the carboxylate substrate. To interpret these in silico predictions under in vivo system, an organized study was conducted with a lactic acid bacteria strain engineered with acrylate pathway. Analysis reported a decreased product formation rate on attainment of inhibitory titer by suspected metabolites and supported the model.
Generation of highly selective monoclonal antibodies inhibiting a recalcitrant protease using decoy designs
Authors: Lee Ki Baek , Dunn Zachary S. , Lopez Tyler , Mustafa Zahid , Ge Xin
Published: July 2020

Matrix metalloproteinase‐12 (MMP‐12), also known as macrophage elastase, is a potent inflammatory mediator and therefore an important pharmacological target. Clinical trial failures of broad‐spectrum compound MMP inhibitors suggested that specificity is the key for a successful therapy. To provide the required selectivity, monoclonal antibody (mAb)‐based inhibitors are on the rise. However, poor production of active recombinant human MMP‐12 catalytic domain (cdMMP‐12) presented a technical hurdle for its inhibitory mAb development. We hypothesized that this problem could be solved by designing an expression‐optimized cdMMP‐12 mutant without structural disruptions at its reaction cleft and surrounding area, and thus isolated active‐site inhibitory mAbs could maintain their binding and inhibition functions toward wild‐type MMP‐12. We combined three advances in the field—PROSS algorithm for cdMMP‐12 mutant design, convex paratope antibody library construction, and functional selection for inhibitory mAbs. As a result, isolated Fab inhibitors showed nanomolar affinity and potency toward cdMMP‐12 with high selectivity and high proteolytic stability. Particularly, Fab LH11 targeted the reaction cleft of wild‐type cdMMP‐12 with 75 nM binding KD and 23 nM inhibition IC50. We expect that our methods can promote the development of mAbs inhibiting important proteases, many of which are recalcitrant to functional production.
Melflufen, a peptide‐conjugated alkylator, is an efficient anti‐neo‐plastic drug in breast cancer cell lines
Authors: Schepsky Alexander , Traustadottir Gunnhildur Asta , Joelsson Jon Petur , Ingthorsson Sævar , Kricker Jennifer , Bergthorsson Jon Thor , Asbjarnarson Arni , Gudjonsson Thorkell , Nupponen Nina , Slipicevic Ana , Lehmann Fredrik , Gudjonsson Thorarinn
Published: July 2020

Melphalan flufenamide (hereinafter referred to as “melflufen”) is a peptide‐conjugated drug currently in phase 3 trials for the treatment of relapsed or refractory multiple myeloma. Due to its lipophilic nature, it readily enters cells, where it is converted to the known alkylator melphalan leading to enrichment of hydrophilic alkylator payloads. Here, we have analysed in vitro and in vivo the efficacy of melflufen on normal and cancerous breast epithelial lines. D492 is a normal‐derived nontumorigenic epithelial progenitor cell line whereas D492HER2 is a tumorigenic version of D492, overexpressing the HER2 oncogene. In addition we used triple negative breast cancer cell line MDA‐MB231. The tumorigenic D492HER2 and MDA‐MB231 cells were more sensitive than normal‐derived D492 cells when treated with melflufen. Compared to the commonly used anti‐cancer drug doxorubicin, melflufen was significantly more effective in reducing cell viability in vitro while it showed comparable effects in vivo. However, melflufen was more efficient in inhibiting metastasis of MDA‐MB231 cells. Melflufen induced DNA damage was confirmed by the expression of the DNA damage proteins ƴH2Ax and 53BP1. The effect of melflufen on D492HER2 was attenuated if cells were pretreated with the aminopeptidase inhibitor bestatin, which is consistent with previous reports demonstrating the importance of aminopeptidase CD13 in facilitating melflufen cleavage. Moreover, analysis of CD13high and CD13low subpopulations of D492HER2 cells and knockdown of CD13 showed that melflufen efficacy is mediated at least in part by CD13. Knockdown of LAP3 and DPP7 aminopeptidases led to similar efficacy reduction, suggesting that also other aminopeptidases may facilitate melflufen conversion. In summary, we have shown that melflufen is a highly efficient anti‐neoplastic agent in breast cancer cell lines and its efficacy is facilitated by aminopeptidases.
Human papillomavirus (HPV) in Chinese oropharyngeal squamous cell carcinoma (OPSCC): A strong predilection for the tonsil
Authors: Xu Tingting , Shen Chunying , Wei Ye , Hu Chaosu , Wang Yu , Xiang Jun , Sun Guo‐Hua , Su Fengtao , Wang Qifeng , Lu Xueguan
Published: July 2020

Objective

Compared with Occident's data, the incidence of Human papillomavirus (HPV)‐driven oropharyngeal squamous cell carcinomas (OPSCCs) had been reported as relatively low in Mainland China. The objective of this study was to report the integrated prevalence of HPV and Epstein‐Barr virus (EBV), and further evaluate the different behaviors of HPV‐positive and ‐negative OPSCCs in eastern China.

Methods

In a cohort of 170 nonmetastatic OPSCCs treated from January 2007 to July 2019, p16 protein expression, HPV genotypes, and Epstein‐Barr virus‐encoded RNA (EBER) were determined by immunohistochemistry (IHC) and in situ hybridization (ISH). The clinical and pathologic findings were further collected and analyzed to comprehensively reveal the behaviors of Chinese OPSCCs.

Results

Out of the 170 tumor tissues evaluated, 57.6% (98) samples had positive p16 expressions. A total of 65.1% (99/152) samples had positive HPV genotypes, besides HPV16 (92/152), HPV11, 18, 33, 53, and 58 were also detected. The positive rate of EBER was 7.2% (9/124), and the co‐infection rate of EBV/HPV was 4.0%. Related to the unequal distributions of p16 expression, HPV‐related tumors arisen from tonsillar and non‐tonsillar accounted for 68.8% (75/109) and 37.7% (23/61) of their cases, respectively (P < .001). With a median follow‐up time of 13.1 months, significant survival advantages of HPV‐related OSPCC were observed; 1‐year OS, PFS, RFS, and MFS were 83.2% vs 96.7% (P < .001), 71.6% vs 96.2% (P < .001), 77.7% vs 96.2% (P = .002), and 90.4% vs 100.0% (P = .024) in p16‐negative and ‐positive cases, respectively.

Conclusions

The relative percent of HPV‐positive OPSCCs in this study is close to the positive rate in many Western countries and a strong predilection was discovered for the tonsillar. The EBV infection and co‐infection of HPV/EBV were largely low. The prognosis of HPV‐positive OSPCCs was more favorable than its negative counterpart.
Acceptability of insects in animal feed: A survey of French consumers
Authors: Bazoche Pascale , Poret Sylvaine
Published: July 2020

Using insects as an alternative protein source is increasingly becoming part of the future food security equation. Westerners tend to be squeamish or phobic about insects; thus, before we can manage this kind of change in the human diet, we need to start by introducing this new protein source into the animal diet. This article investigates the French consumer acceptability of farmed trout fed insect meal instead of fish meal. From an online survey of 327 consumers, the present work set out to identify the determinants of acceptability and determine how information on the benefits of insect meal for fishery resources can change the acceptability. Our statistical analysis highlights three key factors shaping the acceptability of these novel insect‐fed products, namely, being informed, gender and food neophobia. Providing information on the negative effects of overfishing and on insect meal as a viable alternative to fishmeal in aquafeed can improve the acceptability of insects as fish feed. In all, 76% of informed participants would be ready to eat insect‐fed fish against only 64% of uninformed participants. Males appeared readier to eat insect‐fed fish, and the ‘Reluctants’ class, which represented 8% of our sample, was composed of 78% females. The ‘Fans’, which represented 41% of our sample, were more likely to be males and individuals with a lower than average food neophobia score.
Peptidyl Acyloxymethyl Ketones as Activity‐Based Probes for the Main Protease of SARS‐CoV‐2**
Authors: van de Plassche Merel A. T. , Barniol‐Xicota Marta , Verhelst Steven H. L.
Published: July 2020

The global pandemic caused by SARS‐CoV‐2 calls for the fast development of antiviral drugs against this particular coronavirus. Chemical tools to facilitate inhibitor discovery as well as detection of target engagement by hit or lead compounds from high‐throughput screens are therefore in urgent need. We here report novel, selective activity‐based probes that enable detection of the SARS‐CoV‐2 main protease. The probes are based on acyloxymethyl ketone reactive electrophiles combined with a peptide sequence including unnatural amino acids that targets the nonprimed site of the main protease substrate binding cleft. They are the first activity‐based probes for the main protease of coronaviruses and display target labeling within a human proteome without background. We expect that these reagents will be useful in the drug‐development pipeline, not only for the current SARS‐CoV‐2, but also for other coronaviruses.
VDAC oligomer pores: A mechanism in disease triggered by mtDNA release
Authors: Yan Jialong , Liu Wei , Feng Fen , Chen Linxi
Published: July 2020

A recent study suggests that voltage‐dependent anion channel (VDAC) oligomer pores promote mitochondrial outer membrane permeabilization and allow mitochondrial DNA (mtDNA) to be released into the cytosol in live cells. It challenges the notion that only occurs in apoptotic cells via BAX/BAK macropores. Cytosolic mtDNA activates cyclic GMP–AMP synthase (cGAS)–stimulator of IFN gene (STING) pathway and triggers type I interferon (IFN) response thereafter, which ultimately causes systemic lupus erythematosus. Mechanistically, mtDNA can interact with three positively charged residues (Lys12, Arg15, and Lys20) at the N‐terminus of VDAC1, thereby strengthening VDAC1 oligomerization and facilitating mtDNA release. In addition, there are other pathways that can mediate mtDNA release, such as BAX/BAK macropores and virus‐derived pores. The mtDNA released into the cytosol also triggers type I IFN response via the generally accepted cGAS–STING–TANK‐binding kinase 1–IFN regulatory factor 3 axis. Collectively, VDAC oligomer pores provide us an attractive direction for us to understand mtDNA release‐related diseases.
TRIM31 inhibits NLRP3 inflammasome and pyroptosis of retinal pigment epithelial cells through ubiquitination of NLRP3
Authors: Huang Peirong , Liu Wenjia , Chen Jieqiong , Hu Yifan , Wang Yuwei , Sun Junran , Feng Jingyang
Published: July 2020

NOD‐like receptor protein 3 (NLRP3) is associated with age‐related macular degeneration (AMD). Retinal pigment epithelial (RPE) cells serve as the immune defense of macula, and their dysfunction causes clinically relevant changes in AMD. In the present study, oxidized low‐density lipoprotein (ox‐LDL) activated the NLRP3 inflammasome in human RPE cell line ARPE‐19. Our data showed that the expression of NLRP3, interleukin‐1β (IL‐1β), and caspase‐1 and the release of IL‐1β in ARPE‐19 cells were substantially increased by ox‐LDL, whereas the addition of NLRP3 inhibitor INF39 dose‐dependently reversed the effect of ox‐LDL. Overexpression of tripartite motif‐containing protein 31 (TRIM31) also suppressed the effect of ox‐LDL in ARPE‐19 cells. TRIM31 knockdown had similar effects with ox‐LDL but INF39 could block the effect of TRIM31 knockdown. Moreover, TRIM31 could interact with NLRP3 in ARPE‐19 cells. Overexpression of TRIM31 increased NLRP3 ubiquitination. In conclusion, the results propose that TRIM31 could enhance NLRP3 ubiquitination, therefore inhibiting NLRP3 inflammasome and pyroptosis in human RPE cells.
Interleukin‐25 regulates matrix metalloproteinase‐2 and ‐9 expression in periodontal fibroblast cells through ERK and P38MAPK pathways
Authors: Pan Suxun , Zhang Zhen , Li Chengzhang , Yang Dong
Published: July 2020

Interleukin‐25 (IL‐25) has been recognized as a new member of the IL‐17 family and implicated in various inflammatory pathology. We aimed to investigate the effects of IL‐25 on the expression of matrix metalloproteinase‐2 (MMP‐2), MMP‐8, and MMP‐9 in periodontal fibroblast cells (PFCs), cell migration, cytoskeleton F‐actin, and to explore the involved extracellular‐regulated protein kinases (ERKs), P38 mitogen‐activated protein kinase (P38MAPK) signaling pathways, and IL‐17 receptor. To evaluate the expression of MMP‐2, MMP‐8, MMP‐9, and F‐actin, PFCs were treated by various doses of IL‐25 (0, 20, 50, 100, and 500 ng/ml). Protein expression of extracellular metalloproteinase inducer (EMMPRIN) was also evaluated by western blot. Cell scratches experiment was performed to test the cell migration ability. ERK, P38MAPK, and Jun N‐terminal kinase signal pathways and related expression of P‐ERK and P‐P38MAPK were examined after treatment of different doses of IL‐25 and after treatment of inhibitors of ERK and P38MAPK. Immunofluorescence of MMP‐2, MMP‐9, and F‐actin were evaluated after inhibitor treatment. IL‐17RB small interfering RNA was used to examine the receptor of IL‐25. IL‐25 increased the protein expression of MMP‐2 and MMP‐9. MMP‐8 and EMMPRIN expressions were not regulated by IL‐25 in PFCs. Positive IF staining extended strongly from the central part to the whole cell. IL‐25 mediated MMP‐2, MMP‐9, F‐actin expressions and cell migration were regulated by P38MAPK and ERK pathways, and IL‐17RB. SB203580 and U0126 blocked the effects of IL‐25 through the inhibition of ERK, P38MAPK, P‐ERK, and P‐P38MAPK. The data indicate that IL‐25 could regulate cell migration, MMP‐2, and MMP‐9 expression, but not MMP‐8 expression, in PFCs. Moreover, the regulation effects were involved in ERK and P38MAPK pathways, and receptor IL‐17RB.
Peroxiredoxin of Arthrospira platensis derived short molecule YT12 influences antioxidant and anticancer activity
Authors: Sannasimuthu Anbazahan , Ramani Madhura , Pasupuleti Mukesh , Saraswathi Nambiappan T. , Arasu Mariadhas Valan , Al‐Dhabi Naif Abdulla , Arshad Aziz , Mala Kanchana , Arockiaraj Jesu
Published: July 2020

This study demonstrates both the antioxidant and anticancer potential of the novel short molecule YT12 derived from peroxiredoxin (Prx) of spirulina, Arthrospira platensis (Ap). ApPrx showed significant reduction in reactive oxygen species (ROS) against hydrogen peroxide (H2O2) stress. The complementary DNA sequence of ApPrx contained 706 nucleotides and its coding region possessed 546 nucleotides between position 115 and 660. Real‐time quantitative reverse transcription polymerase chain reaction analysis confirmed the messenger RNA expression of ApPrx due to H2O2 exposure in spirulina cells at regular intervals, in which the highest expression was noticed on Day 20. Cytotoxicity assay was performed using human peripheral blood mononuclear cells, and revealed that at 10 μM, the YT12 did not exhibit any notable toxicity. Furthermore, ROS scavenging activity of YT12 was performed using DCF‐DA assay, in which YT12 scavenged a significant amount of ROS at 25 μM in H2O2‐treated blood leukocytes. The intracellular ROS in human colon adenocarcinoma cells (HT‐29) was regulated by oxidative stress, where the YT12 scavenges ROS in HT‐29 cells at 12.5 μM. Findings show that YT12 peptide has anticancer activity, when treated against HT‐29 cells. Through the MTT assay, YT12 showed vital cytotoxicity against HT‐29 cells. These finding suggested that YT12 is a potent antioxidant molecule which defends ROS against oxidative stress and plays a role in redox balance.
Effect of simulated microgravity conditions of hindlimb unloading on mice hematopoietic and mesenchymal stromal cells
Authors: Dai Shiyun , Kong Fanxuan , Liu Chao , Xiao Fengjun , Dong Xiwen , Zhang Yikun , Wang Hua
Published: July 2020

Conditions in space, such as microgravity, may affect the hematopoietic and bone marrow‐derived mesenchymal stromal cells (BM‐MSCs) of astronauts. However, to date, few detailed phenotype change data about the different type of hematopoietic cells have reported. In this study, C57BL/6 mice were randomly divided into two groups: a control group (control) and a hindlimb suspension group (treated). After four weeks of hindlimb suspension, we found that this simulated microgravity (sµg) condition could increase the percentage of monocytes and macrophages and decrease the percentage of B lymphocytes and mature red cells in bone marrow. The percentage of B lymphocytes in the spleen and the red blood cell count in peripheral blood also decreased, consistent with the response of bone marrow. The cytoskeleton in the BM‐MSCs was disrupted. The expression levels of hematopoietic‐related genes, such as fms‐like tyrosine kinase‐3 ligand, granulocyte‐macrophage colony stimulating factor, interleukin‐3, and adipogenic differentiation associated genes, leptin and proliferator‐activated receptor γ type 2, were upregulated under sµg conditions. These results indicated that simulating microgravity can affect the phenotype of certain types of hematopoietic cells and the morphology and gene expression pattern of BM‐MSCs.
Temperature‐Dependent Nanopolyhedron Carbon‐Decorated Sb for High‐Performance Lithium‐Ion Batteries
Authors: Han Qigang , Zhang Xu , Li Xiang , Li Yao , Zhang Wenqiang , Sheng Yalan
Published: July 2020

On the basis of its high theoretical capacity (660 mAh ⋅ g−1) and flat voltage platform, Sb has been considered as a potential anode material for lithium‐ion batteries. However, the large volume changes during the charge/discharge process result in a poor cycling stability and a terrible rate capability, which hinder the further practical application. Herein, metal organic frameworks derived from carbon can be endowed with tunable morphology by pyrolysis of the Sb2O3@ZIF‐8 precursor at different temperatures. Temperature‐dependent carbon matrixes with nano polyhedron are more profitable to relive the volume expansion by heterogeneous nucleation and growth on the surface of Sb. The as‐prepared Sb@C composite can deliver a high reversible capacity of 598.6 mAh ⋅ g−1 at a current density of 100 mA ⋅ g−1 after 100 cycles, which accounts for 91 % of the theoretical capacity of bare Sb. In addition, a reversible capacity of 223 mAh ⋅ g−1 can be maintained even at a current density of 2000 mA ⋅ g−1. The excellent electrochemical characteristics of the Sb@C composites can be attributed to the synergistic effects between Sb and the external carbon matrixes.
Dodecahedral Au/Pt Nanobowls as Robust Plasmonic Electrocatalysts for Methanol Oxidation under Visible‐Light Illumination
Authors: Xu Xiaoxiao , Fang Caihong , Bi Ting , Cui Zhiqing , Zhao Guili , Jiang Xiaomin , Hu Jinwu
Published: July 2020

Plasmonic nanostructures with large absorption areas under resonant excitation have been utilized extensively in photon‐assisted applications. In this work, dodecahedral Au nanobowls were first prepared by an easy and template‐free method only through the introduction of H2PtCl6 and I− during the growth procedure. The Au nanobowls show electron‐field enhancement due to the high curvature of the bowl edge, the open region, and dodecahedral morphology. Au/Pt nanobowls, which couple plasmonic Au and catalytic Pt, were then constructed as plasmonic electrocatalysts for methanol oxidation. The mass activity reached 497.6 mA mg−1 under visible‐light illumination, which is 1.9 times that measured in the dark. Simultaneously, the electrocatalytic stability is also greatly improved under light excitation. The enhanced properties of the plasmonic Au/Pt electrocatalysts are ascribed to the synergistic effect of the plasmon‐enhanced photothermal and hot‐carrier effects on the basis of experimental investigations. This work thus offers an effective methodology to construct efficient plasmonic electrocatalysts for fuel cells.
In Situ Synthesis of Manganese Oxide as an Oxygen‐Evolving Catalyst: A New Strategy
Authors: Abdi Zahra , Bagheri Robabeh , Reza Mohammadi Mohammad , Song Zhenlun , Görlin Mikaela , Dau Holger , Najafpour Mohammad Mahdi
Published: July 2020

All studies on oxygen‐evolution reaction by Mn oxides in the presence of cerium(IV) ammonium nitrate (CAN) have been so far carried out by synthesizing Mn oxides in the first step. And then, followed by the investigation of the Mn oxides in the presence of oxidants for oxygen‐evolution reaction (OER). This paper presents a case study of a new and promising strategy for in situ catalyst synthesis by the adding MnII to either CAN or KMnO4/CAN solution, resulting in the formation of Mn‐based catalysts for OER. The catalysts were characterized by scanning electron microscopy, energy‐dispersive spectroscopy, transmission electron microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, X‐ray absorption spectroscopy, and X‐ray photoelectron spectroscopy. Both compounds contained nano‐sized particles that catalyzed OER in the presence of CAN. The turnover frequencies for both catalysts were 0.02 (mmol
/molMn⋅s).
Water Formation in Non‐Hydrolytic Sol–Gel Routes: Selective Synthesis of Tetragonal and Monoclinic Mesoporous Zirconia as a Case Study
Authors: Wang Yanhui , Bouchneb Maroua , Mighri Rimeh , Alauzun Johan G. , Mutin P. Hubert
Published: July 2020

Several non‐hydrolytic sol–gel syntheses involving different precursors, oxygen donors, and conditions have been screened aiming to selectively produce mesoporous t‐ZrO2 or m‐ZrO2 with significant specific surface areas. The in situ water formation was systematically investigated by Karl Fisher titration of the syneresis liquids. XRD and nitrogen physisorption were employed to characterize the structure and texture of the ZrO2 samples. Significant amounts of water were found in several cases, notably in the reactions of Zr(OnPr)4 with ketones (acetone, 2‐pentanone, acetophenone), and of ZrCl4 with alcohols (benzyl alcohol, ethanol) or acetone. Conversely, the reactions of Zr(OnPr)4 with acetic anhydride or benzyl alcohol at moderate temperature (200 °C) and of ZrCl4 with diisopropyl ether appear strictly non‐hydrolytic. Although reaction time and reaction temperature were also important parameters, the presence of water played a crucial role on the structure of the final zirconia: t‐ZrO2 is favored in strictly non‐hydrolytic routes, while m‐ZrO2 is favored in the presence of significant amounts of water. 1H and 13C NMR analysis of the syneresis liquids allowed us to identify the main reactions responsible for the formation of water and of the oxide network. The morphology of the most interesting ZrO2 samples was further investigated by electron microscopy (SEM, TEM).
The Combination of Cross‐Hyperconjugation and σ‐Conjugation in 2,5‐Oligosilanyl Substituted Siloles
Authors: Pöcheim Alexander , Özpınar Gül Altınbaş , Müller Thomas , Baumgartner Judith , Marschner Christoph
Published: July 2020

Reaction of a 2,5‐dilithiated silole with excess dichlorodimethylsilane gives the respective 2,5‐bis(chlorodimethylsilyl) substituted silole. This compound can be converted to 2,5‐bis(oligosilanyl) substituted siloles by addition of a suitable oligosilanide. In the UV spectra of the thus obtained compounds the lowest energy absorptions are bathochromically shifted compared to the absorptions of the two constituents, namely the 2,5‐disilyl substituted silole and a trisilane. The bathochromic shift is interpreted as being caused by a mixed σ‐conjugation/cross‐hyperconjugation. This assumption is supported by TD‐DFT calculations, which show a significant contribution from Si−Si bonds to the HOMO of the molecule.
A Journey from Thermally Tunable Synthesis to Spectroscopy of Phenylmethanimine in Gas Phase and Solution
Authors: Melli Alessio , Potenti Simone , Melosso Mattia , Herbers Sven , Spada Lorenzo , Gualandi Andrea , Lengsfeld Kevin G. , Dore Luca , Buschmann Philipp , Cozzi Pier Giorgio , Grabow Jens‐Uwe , Barone Vincenzo , Puzzarini Cristina
Published: July 2020

Phenylmethanimine is an aromatic imine with a twofold relevance in chemistry: organic synthesis and astrochemistry. To tackle both aspects, a multidisciplinary strategy has been exploited and a new, easily accessible synthetic approach to generate stable imine‐intermediates in the gas phase and in solution has been introduced. The combination of this formation pathway, based on the thermal decomposition of hydrobenzamide, with a state‐of‐the‐art computational characterization of phenylmethanimine laid the foundation for its first laboratory observation by means of rotational electric resonance spectroscopy. Both E and Z isomers have been accurately characterized, thus providing a reliable basis to guide future astronomical observations. A further characterization has been carried out by nuclear magnetic resonance spectroscopy, showing the feasibility of this synthetic approach in solution. The temperature dependence as well as possible mechanisms of the thermolysis process have been examined.
Photoredox‐Mediated Hydrogen Isotope Exchange Reactions of Amino‐Acids, Peptides, and Peptide‐Derived Drugs
Authors: Legros Fabien , Fernandez‐Rodriguez Patricia , Mishra Anurag , Weck Remo , Bauer Armin , Sandvoss Martin , Ruf Sven , Méndez María , Mora‐Radó Helena , Rackelmann Nils , Pöverlein Christoph , Derdau Volker
Published: July 2020

Hydrogen isotopically labelled compounds are essential diagnostic tools in drug research and development, as they provide vital information about the biological metabolism of drug candidates and their metabolites. Herein we report a photoredox‐initiated hydrogen atom transfer (HAT) protocol which efficiently and selectively introduces deuterium or tritium at C(sp3)−H bonds, utilizing heavy water (D2O or T2O) as the hydrogen isotope source, and a guanidine base. This protocol has been successfully applied to the incorporation of deuterium in several amino acids (lysine, glycine and proline) and small peptides. Finally, the method has been applied to tritium, because tritium‐labelled peptides are essential for application in biological experiments, such as ligand‐binding assays, or absorption, distribution, metabolism, and excretion (ADME) studies.