bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differences in Self-Recognition between Secreted Antibody and Membrane-Bound B Cell Antigen Receptor
Authors: Iype Joseena , Datta Moumita , Khadour Ahmad , Übelhart Rudolf , Nicolò Antonella , Rollenske Tim , Dühren-von Minden Marcus , Wardemann Hedda , Maity Palash C. , Jumaa Hassan 
Published: January 2019

Abstract
The random gene segment rearrangement during B cell development ensures Ab repertoire diversity. Because this process might generate autoreactive specificities, it has been proposed that stringent selection mechanisms prevent the development of autoreactive B cells. However, conventional assays to identify autoreactive B cells usually employ in vitro–generated Abs, which differ from membrane-bound BCRs. In this study, we used a cell-based assay to investigate the autoreactivity of membrane-bound BCRs derived from different B cell developmental stages of human peripheral blood. Contrasted to soluble Ab counterparts, only a few of the tested BCRs were autoreactive, although the cell-based assay sensitively detects feeble Ag recognition of a germline-reverted murine BCR that was selected after OVA immunization of mice, whereas conventional assays failed to do so. Together, these data suggest that proper identification of autoreactive B cells requires the membrane-bound BCR, as the soluble Ab may largely differ from its BCR counterpart in Ag binding.
Fc Sialylation Prolongs Serum Half-Life of Therapeutic Antibodies
Authors: Bas Mathilde , Terrier Aurélie , Jacque Emilie , Dehenne Aurélie , Pochet-Béghin Virginie , Beghin Cécile , Dezetter Anne-Sophie , Dupont Gilles , Engrand Anaïs , Beaufils Benjamin , Mondon Philippe , Fournier Nathalie , de Romeuf Christophe , Jorieux Sylvie , Fontayne Alexandre , Mars Lennart T. , Monnet Céline 
Published: January 2019

Abstract
The long serum t1/2 of IgGs is ensured by their interaction with the neonatal Fc receptor (FcRn), which salvages IgG from intracellular degradation. Fc glycosylation is thought not to influence FcRn binding and IgG longevity in vivo. In this article, we demonstrate that hypersialylation of asparagine 297 (N297) enhances IgG serum persistence. This polarized glycosylation is achieved using a novel Fc mutation, a glutamate residue deletion at position 294 (Del) that endows IgGs with an up to 9-fold increase in serum lifespan. The strongest impact was observed when the Del was combined with Fc mutations improving FcRn binding (Del-FcRn+). Enzymatic desialylation of a Del-FcRn+ mutant or its production in a cell line unable to hypersialylate reduced the in vivo serum t1/2 of the desialylated mutants to that of native FcRn+ mutants. Consequently, our study proves that sialylation of the N297 sugar moiety has a direct impact on human IgG serum persistence.
Abatacept Targets T Follicular Helper and Regulatory T Cells, Disrupting Molecular Pathways That Regulate Their Proliferation and Maintenance
Authors: Glatigny Simon , Höllbacher Barbara , Motley Samantha J. , Tan Cathy , Hundhausen Christian , Buckner Jane H. , Smilek Dawn , Khoury Samia J. , Ding Linna , Qin Tielin , Pardo Jorge , Nepom Gerald T. , Turka Laurence A. , Harris Kristina M. , Campbell Daniel J. , Bettelli Estelle 
Published: January 2019

Abstract
Abatacept is a CTLA-4-Ig fusion protein that binds to the costimulatory ligands CD80 and CD86 and blocks their interaction with the CD28 and CTLA-4 receptors expressed by T cells, therefore inhibiting T cell activation and function. Abatacept has shown clinical efficacy in treating some autoimmune diseases but has failed to show clinical benefit in other autoimmune conditions. The reasons for these disparate results are not clear and warrant further investigation of abatacept’s mode of action. Longitudinal specimens from the Immune Tolerance Network's A Cooperative Clinical Study of Abatacept in Multiple Sclerosis trial were used to examine the effects of abatacept treatment on the frequency and transcriptional profile of specific T cell populations in peripheral blood. We found that the relative abundance of CD4+ T follicular helper (Tfh) cells and regulatory T cells was selectively decreased in participants following abatacept treatment. Within both cell types, abatacept reduced the proportion of activated cells expressing CD38 and ICOS and was associated with decreased expression of genes that regulate cell-cycle and chromatin dynamics during cell proliferation, thereby linking changes in costimulatory signaling to impaired activation, proliferation, and decreased abundance. All cellular and molecular changes were reversed following termination of abatacept treatment. These data expand upon the mechanism of action of abatacept reported in other autoimmune diseases and identify new transcriptional targets of CD28-mediated costimulatory signaling in human regulatory T and Tfh cells, further informing on its potential use in diseases associated with dysregulated Tfh activity.
Campaign of Giants--The Battle for Petersburg
Authors: Greene A. Wilson , Gallagher Gary W. 
Published: January 2019

Grinding, bloody, and ultimately decisive, the Petersburg Campaign was the Civil War's longest and among its most complex. Ulysses S. Grant and Robert E. Lee squared off for more than nine months in their struggle for Petersburg, the key to the Confederate capital at Richmond. Featuring some of the war's most notorious battles, the campaign played out against a backdrop of political drama and crucial fighting elsewhere, with massive costs for soldiers and civilians alike. After failing to bull his way into Petersburg, Grant concentrated on isolating the city from its communications with the rest of the surviving Confederacy, stretching Lee's defenses to the breaking point. When Lee's desperate breakout attempt failed in March 1865, Grant launched his final offensives that forced the Confederates to abandon the city on April 2, 1865. A week later, Lee surrendered at Appomattox Court House. Here A. Wilson Greene opens his sweeping new three-volume history of the Petersburg Campaign, taking readers from Grant's crossing of the James in mid-June 1864 to the fateful Battle of the Crater on July 30. Full of fresh insights drawn from military, political, and social history, A Campaign of Giants is destined to be the definitive account of the campaign. With new perspectives on operational and tactical choices by commanders, the experiences of common soldiers and civilians, and the significant role of the United States Colored Troops in the fighting, this book offers essential reading for all those interested in the history of the Civil War.
Strong reduction in diapause survival under warm and humid overwintering conditions in a temperate‐zone butterfly
Authors: Klockmann Michael , Fischer Klaus 
Published: January 2019

AbstractAnthropogenic climate change poses substantial challenges to biodiversity conservation. Effects of climate change on summer conditions and associated heat and desiccation stress have attracted much research interest, while the implications of changing winter conditions on hibernation have hitherto received fairly little attention. This is surprising as the latter may also strongly affect biodiversity. By investigating the effects of overwintering conditions on diapause and postdiapause survival in a temperate‐zone butterfly, we found that warmer and moister winter conditions substantially decreased survival rates. However, detrimental effects were restricted to survival during diapause and subsequent development and had no clear effects on butterfly performance. We suggest that overwintering survival is an important driver of vulnerability to climate change. Our study stresses the importance of collating more data on overwintering survival in species with different hibernation strategies to predict the impact of ongoing climate change on biodiversity.
Metallogels: Availability, Applicability, and Advanceability
Authors: Wu Huiqiong , Zheng Jun , Kjøniksen Anna‐Lena , Wang Wei , Zhang Yi , Ma Jianmin 
Published: January 2019

AbstractIntroducing metal components into gel matrices provides an effective strategy to develop soft materials with advantageous properties such as: optical activity, conductivity, magnetic response activity, self‐healing activity, catalytic activity, etc. In this context, a thorough overview of application‐oriented metallogels is provided. Considering that many well‐established metallogels start from serendipitous discoveries, insights into the structure–gelation relationship will offer a profound impact on the development of metallogels. Initially, design strategies for discovering new metallogels are discussed, then the advanced applications of metallogels are summarized. Finally, perspectives regarding the design of metallogels, the potential applications of metallogels and their derivative materials are briefly proposed.
Solvent‐Induced Self‐Assembly Strategy to Synthesize Well‐Defined Hierarchically Porous Polymers
Authors: Gao Tu‐Nan , Wang Tao , Wu Wei , Liu Yali , Huo Qisheng , Qiao Zhen‐An , Dai Sheng 
Published: January 2019

AbstractPorous polymers with well‐orchestrated nanomorphologies are useful in many fields, but high surface area, hierarchical structure, and ordered pores are difficult to be satisfied in one polymer simultaneously. Herein, a solvent‐induced self‐assembly strategy to synthesize hierarchical porous polymers with tunable morphology, mesoporous structure, and microporous pore wall is reported. The poly(ethylene oxide)‐b‐polystyrene (PEO‐b‐PS) diblock copolymer micelles are cross‐linked via Friedel–Crafts reaction, which is a new way to anchor micelles into porous polymers with well‐defined structure. Varying the polarity of the solvent has a dramatic effect upon the oleophobic/oleophylic interaction, and the self‐assembly structure of PEO‐b‐PS can be tailored from aggregated nanoparticles to hollow spheres even mesoporous bulk. A morphological phase diagram is accomplished to systematically evaluate the influence of the composition of PEO‐b‐PS and the mixed solvent component on the pore structure and morphology of products. The hypercrosslinked hollow polymer spheres provide a confined microenvironment for the in situ reduction of K2PdCl4 to ultrasmall Pd nanoparticles, which exhibit excellent catalytic performance in solvent‐free catalytic oxidation of hydrocarbons and alcohols.
Alkali‐Metal‐Intercalated Percolation Network Regulates Self‐Assembled Electronic Aromatic Molecules
Authors: Hu Yong , Zhong Guohua , Guan Ying‐Shi , Lee Nam Hoon , Zhang Yuan , Li Yang , Mitchell Travis , Armstrong Jason N. , Benedict Jason , Hla Saw‐Wai , Ren Shenqiang 
Published: January 2019

AbstractIn the continuously growing field of correlated electronic molecular crystals, there is significant interest in addressing alkali‐metal‐intercalated aromatic hydrocarbons, in which the possibility of high‐temperature superconductivity emerges. However, searching for superconducting aromatic molecular crystals remains elusive due to their small shielding fraction volume. To exploit this potential, a design principle for percolation networks of technologically important film geometry is indispensable. Here the effect of potassium‐intercalation is shown on the percolation network in self‐assembled aromatic molecular crystals. It is demonstrated that one‐dimensional (1D) dipole pairs, induced by dipole interaction, regulate the conductivity, as well as the electronic and optical transitions, in alkali‐metal‐intercalated molecular electronic crystals. A solid‐solution growth methodology of aromatic molecular films with a broad range of stability is developed to uncover electronic and optical transitions of technological importance. The light‐induced electron interactions enhance the charge‐carrier itinerancy, leading to a switchable metal‐to‐insulator transition. This discovery opens a route for the development of aromatic molecular electronic solids and long‐term modulation of electronic efficacy in nanotechnologically important thin films.
Large‐Area, Optical Variable‐Color Metasurfaces Based on Pixelated Plasmonic Nanogratings
Authors: Wu Shangliang , Ye Yan , Duan Huigao , Gu Yu , Chen Linsen 
Published: January 2019

AbstractColor printing based on plasmonic nanostructures has attracted much attention due to its broad potential applications. It is still an open question regarding how to achieve large‐area plasmonic colors for practical use. In this study, large‐area plasmonic metasurfaces that incorporate a dielectric grating, an aluminum nanopatch array, and a silicon nitride layer are designed and fabricated. The asymmetric geometry of the metasurfaces produces a strong asymmetry‐induced color rendering effect, wherein different transmitted colors are observed in perpendicular planes with the same incident angle. Originating from surface plasmonic resonance and a guided mode resonance, a transmission efficiency of ≈60% is achieved. Furthermore, distinctive colors covering the entire visible range are generated by varying the grating period. Remarkably, large‐area colorful surfaces based on pixelated nanogratings with different periods can be fabricated using continuously variable spatial frequency photolithography. The experimental results coincide with simulations and show great potential for various applications such as large‐area color printing and anti‐counterfeiting certifications.
Ethnicity, educational attainment, and physical health of older adults in the United States
Authors: Assari Shervin 
Published: January 2019

AbstractObjectiveMinorities’ diminished returns theory suggests that socioeconomic status (SES) resources generate fewer health benefits for racial and ethnic minority groups, compared to the majority group. The current study aimed to compare Hispanic and non‐Hispanic white older adults for the association between educational attainment and poor physical self‐rated health (SRH).MethodsThe first wave of the University of Michigan National Poll on Healthy Aging (UM‐NPHA) included 1820 older adults who were 50‐80 years old and were either non‐Hispanic white (n = 1618) or Hispanic white (n = 202). The main independent variable of interest was educational attainment. The main dependent variable of interest was poor physical SRH. Gender, age, marital status, and employment status were covariates. Ethnicity was the focal effect modifier.ResultsOverall, higher level of educational attainment was associated with better physical SRH. A significant interaction was found between ethnicity and level of educational attainment, which was indicative of a smaller physical SRH gain due to high educational attainment for Hispanic white compared to non‐Hispanic white older adults. In ethnic‐specific models, we found evidence suggesting that high educational attainment reduced the odds of poor physical SRH for non‐Hispanic whites but not for Hispanic whites.ConclusionCompared to non‐Hispanic whites, Hispanic whites gain less physical SRH benefits from their educational attainment.
Boron‐Catalyzed Carbonate Functionality Transfer Reaction
Authors: Rao Santhosh , Ashwathappa Puneeth Kumar Someswara , Prabhu Kandikere Ramaiah 
Published: January 2019

AbstractA carbene transfer reaction has been studied to understand the nature of the tris(pentafluorophenyl)borane stabilized donor‐acceptor carbene. For this, a carbonate (or dicarbonate) molecule has been employed resulting in an overall carbonate functionality transfer. The results show that the diazo‐derived carbenic carbon displays an electrophilic character. This also presents an opportunity to develop future carbene transfer reactions using a multitude of unconventional nucleophiles with the tris(pentafluorophenyl)borane catalyst.
Tumor‐Microenvironment‐Induced Degradation of Ultrathin Gadolinium Oxide Nanoscrolls for Magnetic‐Resonance‐Imaging‐Monitored, Activatable Cancer Chemotherapy
Authors: Wu Miaomiao , Xue Yumeng , Li Na , Zhao Hongyang , Lei Bo , Wang Min , Wang Jianwei , Luo Meng , Zhang Chao , Du Yaping , Yan Chunhua 
Published: January 2019

AbstractThe development of biodegradable inorganic nanoparticles with a tumor microenvironment‐activated therapeutic mode of action is urgently needed for precision cancer medicine. Herein, the synthesis of ultrathin lanthanide nanoscrolls (Gd2O3 NSs) is reported, which biodegrade upon encountering the tumor microenvironment. The Gd2O3 NSs showed highly controlled magnetic properties, which enabled their high‐resolution magnetic resonance imaging (MRI). Importantly, Gd2O3 NSs degrade in a pH‐responsive manner and selectively penetrate tumor tissue, enabling the targeted release of anti‐cancer drugs. Gd2O3 NSs can be efficiently loaded with an anti‐cancer drug (DOX, 80 %) and significantly inhibit tumor growth with negligible cellular and tissue toxicity both in vitro and in vivo. This study may provide a novel strategy to design tumor microenvironment‐responsive inorganic nanomaterials for biocompatible bioimaging and biodegradation‐enhanced cancer therapy.
Unraveling the Homologation Reaction Sequence of the Zeolite‐Catalyzed Ethanol‐to‐Hydrocarbons Process
Authors: Chowdhury Abhishek Dutta , Lucini Paioni Alessandra , Whiting Gareth T. , Fu Donglong , Baldus Marc , Weckhuysen Bert M. 
Published: January 2019

AbstractAlthough industrialized, the mechanism for catalytic upgrading of bioethanol over solid‐acid catalysts (that is, the ethanol‐to‐hydrocarbons (ETH) reaction) has not yet been fully resolved. Moreover, mechanistic understanding of the ETH reaction relies heavily on its well‐known “sister‐reaction” the methanol‐to‐hydrocarbons (MTH) process. However, the MTH process possesses a C1‐entity reactant and cannot, therefore, shed any light on the homologation reaction sequence. The reaction and deactivation mechanism of the zeolite H‐ZSM‐5‐catalyzed ETH process was elucidated using a combination of complementary solid‐state NMR and operando UV/Vis diffuse reflectance spectroscopy, coupled with on‐line mass spectrometry. This approach establishes the existence of a homologation reaction sequence through analysis of the pattern of the identified reactive and deactivated species. Furthermore, and in contrast to the MTH process, the deficiency of any olefinic‐hydrocarbon pool species (that is, the olefin cycle) during the ETH process is also noted.
Active‐Oxygen‐Enhanced Homogeneous Nucleation of Lithium Metal on Ultrathin Layered Double Hydroxide
Authors: Li Zhenhua , Liu Ke , Fan Kui , Yang Yusen , Shao Mingfei , Wei Min , Duan Xue 
Published: January 2019

AbstractThe development of safe lithium‐metal anodes is crucial for the next‐generation rechargeable batteries. To stabilize Li metal anodes, pre‐planting Li nucleation seeds on lithiophilic substrates is an efficient strategy to regulate initial nucleation process of Li metal. Now, activated ultrathin layered double hydroxide (U‐LDHs) are reported as a promising lithiophilic 2D material to realize the uniform deposition of Li metal. The experimental studies and DFT calculations reveal that the active oxygen on U‐LDHs provides abundant atomic‐scale active sites for Li homogeneous nucleation and plating. Moreover, the lithiophilic properties of active oxygen is also related to its coordination environments. This work opens up an opportunity to more accurate regulation and understanding of Li nucleation from atomic‐scale based on 2D ultrathin materials.
Dual Gold/Silver Catalysis Involving Alkynylgold(III) Intermediates Formed by Oxidative Addition and Silver‐Catalyzed C−H Activation for the Direct Alkynylation of Cyclopropenes
Authors: Yang Yangyang , Antoni Patrick , Zimmer Marc , Sekine Kohei , Mulks Florian F. , Hu Long , Zhang Lumin , Rudolph Matthias , Rominger Frank , Hashmi A. Stephen K. 
Published: January 2019

AbstractWhile gold‐mediated synergistic catalytic processes involving transmetalations with other metals are well understood, AuI/AuIII cycles in these reactions are rarely reported. Herein a gold‐catalyzed direct alkynylation of cyclopropenes is enabled by two operating catalytic cycles, an oxidative catalytic cycle involving an alkynyl AuIII complex formed by oxidative addition and one involving a silver‐mediated C−H activation.
Extending the Lifetime of Native GTP‐Bound Ras for Site‐Resolved NMR Measurements: Quantifying the Allosteric Dynamics
Authors: Chen Xiaomin , Yao Haijie , Wang Hui , Mao Yunyun , Liu Dan , Long Dong 
Published: January 2019

AbstractCharacterization of native GTP‐bound Ras is important for an appreciation of its cellular signaling and for the design of inhibitors, which however has been depressed by its intrinsic instability. Herein, an effective approach for extending the lifetime of Ras⋅GTP samples by exploiting the active role of Son of Sevenless (Sos) is demonstrated that sustains the activated state of Ras. This approach, combined with a postprocessing method that suppresses residual Ras⋅GDP signals, is applied to the site‐resolved NMR measurement of the allosteric dynamics of Ras⋅GTP. The observed network of concerted motions well covers the recently identified allosteric inhibitor‐binding pockets, but the motions are more confined than those of Ras⋅GppNHp, advocating the use of native GTP for development of allosteric inhibitors. The Sos‐based approach is anticipated to generally facilitate experiments on active Ras when native GTP is preferred.
Secondary‐Ion Mass Spectrometry Images Cardiolipins and Phosphatidylethanolamines at the Subcellular Level
Authors: Tian Hua , Sparvero Louis J. , Blenkinsopp Paul , Amoscato Andrew A. , Watkins Simon C. , Bayır Hülya , Kagan Valerian E. , Winograd Nicholas 
Published: January 2019

AbstractMillions of diverse molecules constituting the lipidome act as important signals within cells. Of these, cardiolipin (CL) and phosphatidylethanolamine (PE) participate in apoptosis and ferroptosis, respectively. Their subcellular distribution is largely unknown. Imaging mass spectrometry is capable of deciphering the spatial distribution of multiple lipids at subcellular levels. Here we report the development of a unique 70 keV gas‐cluster ion beam that consists of (CO2)n+(n>10 000) projectiles. Coupled with direct current beam buncher‐time‐of‐flight secondary‐ion mass spectrometry, it is optimized for sensitivity towards high‐mass species (up to m/z 3000) at high spatial resolution (1 μm). In combination with immunohistochemistry, phospholipids, including PE and CL, have been assessed in subcellular compartments of mouse hippocampal neuronal cells and rat brain tissue.
Site‐Resolved Cu2O Catalysis in the Oxidation of CO
Authors: Zhang Zhenhua , Wu Hong , Yu Zongyou , Song Rui , Qian Kun , Chen Xuanye , Tian Jie , Zhang Wenhua , Huang Weixin 
Published: January 2019

AbstractThe identification of the contribution of different surface sites to the catalytic activity of a catalyst nanoparticle is one of the most challenging issues in the fundamental studies of heterogeneous catalysis. We herein demonstrate an effective strategy of using a series of uniform cubic Cu2O nanocrystals with different sizes to identify the intrinsic activity and contributions of face and edge sites in the catalysis of CO oxidation by a combination of reaction kinetics analysis and DFT calculations. Cu2O nanocrystals undergo in situ surface oxidation forming CuO thin films during CO oxidation. As the average size of the cubic Cu2O nanocrystals decreases from 1029 nm to 34 nm, the dominant active sites contributing to the catalytic activity switch from face sites to edge sites. These results reveal the interplay between the intrinsic catalytic activity and the density of individual types of surface sites on a catalyst nanoparticle in determining their contributions to the catalytic activity.