bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of extracellular vesicles in renal fibrosis
Authors: Jing H. , Tang S. , Lin S. , Liao M. , Chen H. , Zhou J. 
Published: May 2019

AbstractAs a particularly important mediator of intercellular communication, extracellular vesicles (EVs) have been proved to be extensively involved in various system diseases over the past two decades, including in renal diseases. As is well-known, renal fibrosis is the common pathological process of any ongoing renal disease or adaptive repair of kidney injury based on current knowledge. Although much work has been performed focusing on EVs in various renal diseases, the role of EVs in renal fibrosis has not been described in detail and summarized. In this review, we provide a brief overview of the definition, classification and biological process of EVs. Then, the potential mechanisms of EVs in renal fibrosis are illustrated. Lastly, recent advances in EVs and the implications of EVs for diagnosis and therapy in renal fibrosis disease are introduced. We look forward to a more comprehensive understanding of EVs in renal fibrosis, which could be a boon to patients with renal fibrosis disease.
Transient opening of trimeric prefusion RSV F proteins
Authors: Gilman Morgan S. A. , Furmanova-Hollenstein Polina , Pascual Gabriel , B. van ‘t Wout Angélique , Langedijk Johannes P. M. , McLellan Jason S. 
Published: May 2019

AbstractThe respiratory syncytial virus (RSV) F glycoprotein is a class I fusion protein that mediates viral entry and is a major target of neutralizing antibodies. Structures of prefusion forms of RSV F, as well as other class I fusion proteins, have revealed compact trimeric arrangements, yet whether these trimeric forms can transiently open remains unknown. Here, we perform structural and biochemical studies on a recently isolated antibody, CR9501, and demonstrate that it enhances the opening of prefusion-stabilized RSV F trimers. The 3.3 Å crystal structure of monomeric RSV F bound to CR9501, combined with analysis of over 25 previously determined RSV F structures, reveals a breathing motion of the prefusion conformation. We also demonstrate that full-length RSV F trimers transiently open and dissociate on the cell surface. Collectively, these findings have implications for the function of class I fusion proteins, as well as antibody prophylaxis and vaccine development for RSV.
Regeneration of severely damaged lungs using an interventional cross-circulation platform
Authors: Guenthart Brandon A. , O’Neill John D. , Kim Jinho , Queen Dawn , Chicotka Scott , Fung Kenmond , Simpson Michael , Donocoff Rachel , Salna Michael , Marboe Charles C. , Cunningham Katherine , Halligan Susan P. , Wobma Holly M. , Hozain Ahmed E. , Romanov Alexander , Vunjak-Novakovic Gordana , Bacchetta Matthew 
Published: May 2019

AbstractThe number of available donor organs limits lung transplantation, the only lifesaving therapy for the increasing population of patients with end-stage lung disease. A prevalent etiology of injury that renders lungs unacceptable for transplantation is gastric aspiration, a deleterious insult to the pulmonary epithelium. Currently, severely damaged donor lungs cannot be salvaged with existing devices or methods. Here we report the regeneration of severely damaged lungs repaired to meet transplantation criteria by utilizing an interventional cross-circulation platform in a clinically relevant swine model of gastric aspiration injury. Enabled by cross-circulation with a living swine, prolonged extracorporeal support of damaged lungs results in significant improvements in lung function, cellular regeneration, and the development of diagnostic tools for non-invasive organ evaluation and repair. We therefore propose that the use of an interventional cross-circulation platform could enable recovery of otherwise unsalvageable lungs and thus expand the donor organ pool.
Mortality causes universal changes in microbial community composition
Authors: Abreu Clare I. , Friedman Jonathan , Andersen Woltz Vilhelm L. , Gore Jeff 
Published: May 2019

AbstractAll organisms are sensitive to the abiotic environment, and a deteriorating environment can cause extinction. However, survival in a multispecies community depends upon interactions, and some species may even be favored by a harsh environment that impairs others, leading to potentially surprising community transitions as environments deteriorate. Here we combine theory and laboratory microcosms to predict how simple microbial communities will change under added mortality, controlled by varying dilution. We find that in a two-species coculture, increasing mortality favors the faster grower, confirming a theoretical prediction. Furthermore, if the slower grower dominates under low mortality, the outcome can reverse as mortality increases. We find that this tradeoff between growth and competitive ability is prevalent at low dilution, causing outcomes to shift dramatically as dilution increases, and that these two-species shifts propagate to simple multispecies communities. Our results argue that a bottom-up approach can provide insight into how communities change under stress.
Competition for nutrients and its role in controlling immune responses
Authors: Kedia-Mehta Nidhi , Finlay David K. 
Published: May 2019

AbstractChanges in cellular metabolism are associated with the activation of diverse immune subsets. These changes are fuelled by nutrients including glucose, amino acids and fatty acids, and are closely linked to immune cell fate and function. An emerging concept is that nutrients are not equally available to all immune cells, suggesting that the regulation of nutrient utility through competitive uptake and use is important for controlling immune responses. This review considers immune microenvironments where nutrients become limiting, the signalling alterations caused by insufficient nutrients, and the importance of nutrient availability in the regulation of immune responses.
Enhancing the performance of pure organic room-temperature phosphorescent luminophores
Authors: Kenry  , Chen Chengjian , Liu Bin 
Published: May 2019

AbstractOnce considered the exclusive property of metal complexes, the phenomenon of room-temperature phosphorescence (RTP) has been increasingly realized in pure organic luminophores recently. Using precise molecular design and synthetic approaches to modulate their weak spin–orbit coupling, highly active triplet excitons, and ultrafast deactivation, organic luminophores can be endowed with long-lived and bright RTP characteristics. This has sparked intense explorations into organic luminophores with enhanced RTP features for different applications. This Review discusses the fundamental mechanism of RTP in pure organic luminophores, followed by design principles, enhancement strategies, and formulation methods to achieve highly phosphorescent and long-lived organic RTP luminophores even in aqueous media. The current challenges and future directions of this field are also discussed in the summary and outlook.
Triplon band splitting and topologically protected edge states in the dimerized antiferromagnet
Authors: Nawa Kazuhiro , Tanaka Kimihiko , Kurita Nobuyuki , Sato Taku J. , Sugiyama Haruki , Uekusa Hidehiro , Ohira-Kawamura Seiko , Nakajima Kenji , Tanaka Hidekazu 
Published: May 2019

AbstractSearch for topological materials has been actively promoted in the field of condensed matter physics for their potential application in energy-efficient information transmission and processing. Recent studies have revealed that topologically invariant states, such as edge states in topological insulators, can emerge not only in a fermionic electron system but also in a bosonic system, enabling nondissipative propagation of quasiparticles. Here we report the topologically nontrivial triplon bands measured by inelastic neutron scattering on the spin-1/2 two-dimensional dimerized antiferromagnet Ba2CuSi2O6Cl2. The excitation spectrum exhibits two triplon bands that are clearly separated by a band gap due to a small alternation in interdimer exchange interaction, consistent with a refined crystal structure. By analytically modeling the triplon dispersion, we show that Ba2CuSi2O6Cl2 is the first bosonic realization of the coupled Su-Schrieffer-Heeger model, where the presence of topologically protected edge states is prompted by a bipartite nature of the lattice.
Ribosome biogenesis during cell cycle arrest fuels EMT in development and disease
Authors: Prakash Varsha , Carson Brittany B. , Feenstra Jennifer M. , Dass Randall A. , Sekyrova Petra , Hoshino Ayuko , Petersen Julian , Guo Yuan , Parks Matthew M. , Kurylo Chad M. , Batchelder Jake E. , Haller Kristian , Hashimoto Ayako , Rundqivst Helene , Condeelis John S. , Allis C. David , Drygin Denis , Nieto M. Angela , Andäng Michael , Percipalle Piergiorgio , Bergh Jonas , Adameyko Igor , Farrants Ann-Kristin Östlund , Hartman Johan , Lyden David , Pietras Kristian , Blanchard Scott C. , Vincent C. Theresa 
Published: May 2019

AbstractRibosome biogenesis is a canonical hallmark of cell growth and proliferation. Here we show that execution of Epithelial-to-Mesenchymal Transition (EMT), a migratory cellular program associated with development and tumor metastasis, is fueled by upregulation of ribosome biogenesis during G1/S arrest. This unexpected EMT feature is independent of species and initiating signal, and is accompanied by release of the repressive nucleolar chromatin remodeling complex (NoRC) from rDNA, together with recruitment of the EMT-driving transcription factor Snai1 (Snail1), RNA Polymerase I (Pol I) and the Upstream Binding Factor (UBF). EMT-associated ribosome biogenesis is also coincident with increased nucleolar recruitment of Rictor, an essential component of the EMT-promoting mammalian target of rapamycin complex 2 (mTORC2). Inhibition of rRNA synthesis in vivo differentiates primary tumors to a benign, Estrogen Receptor-alpha (ERα) positive, Rictor-negative phenotype and reduces metastasis. These findings implicate the EMT-associated ribosome biogenesis program with cellular plasticity, de-differentiation, cancer progression and metastatic disease.
Enveloped viruses distinct from HBV induce dissemination of hepatitis D virus in vivo
Authors: Perez-Vargas Jimena , Amirache Fouzia , Boson Bertrand , Mialon Chloé , Freitas Natalia , Sureau Camille , Fusil Floriane , Cosset François-Loïc 
Published: May 2019

AbstractHepatitis D virus (HDV) doesn’t encode envelope proteins for packaging of its ribonucleoprotein (RNP) and typically relies on the surface glycoproteins (GPs) from hepatitis B virus (HBV) for virion assembly, envelopment and cellular transmission. HDV RNA genome can efficiently replicate in different tissues and species, raising the possibility that it evolved, and/or is still able to transmit, independently of HBV. Here we show that alternative, HBV-unrelated viruses can act as helper viruses for HDV. In vitro, envelope GPs from several virus genera, including vesiculovirus, flavivirus and hepacivirus, can package HDV RNPs, allowing efficient egress of HDV particles in the extracellular milieu of co-infected cells and subsequent entry into cells expressing the relevant receptors. Furthermore, HCV can propagate HDV infection in the liver of co-infected humanized mice for several months. Further work is necessary to evaluate whether HDV is currently transmitted by HBV-unrelated viruses in humans.
Tissue-specific (ts)CRISPR as an efficient strategy for in vivo screening in Drosophila
Authors: Meltzer Hagar , Marom Efrat , Alyagor Idan , Mayseless Oded , Berkun Victoria , Segal-Gilboa Netta , Unger Tamar , Luginbuhl David , Schuldiner Oren 
Published: May 2019

AbstractGene editing by CRISPR/Cas9 is commonly used to generate germline mutations or perform in vitro screens, but applicability for in vivo screening has so far been limited. Recently, it was shown that in Drosophila, Cas9 expression could be limited to a desired group of cells, allowing tissue-specific mutagenesis. Here, we thoroughly characterize tissue-specific (ts)CRISPR within the complex neuronal system of the Drosophila mushroom body. We report the generation of a library of gRNA-expressing plasmids and fly lines using optimized tools, which provides a valuable resource to the fly community. We demonstrate the application of our library in a large-scale in vivo screen, which reveals insights into developmental neuronal remodeling.
Superlattice by charged block copolymer self-assembly
Authors: Shim Jimin , Bates Frank S. , Lodge Timothy P. 
Published: May 2019

AbstractCharged block copolymers are of great interest due to their unique self-assembly and physicochemical properties. Understanding of the phase behavior of charged block copolymers, however, is still at a primitive stage. Here we report the discovery of an intriguing superlattice morphology from compositionally symmetric charged block copolymers, poly[(oligo(ethylene glycol) methyl ether methacrylate–co–oligo(ethylene glycol) propyl sodium sulfonate methacrylate)]–b–polystyrene (POEGMA–PS), achieved by systematic variation of the molecular structure in general, and the charge content in particular. POEGMA–PS self-assembles into a superlattice lamellar morphology, a previously unknown class of diblock nanostructures, but strikingly similar to oxygen-deficient perovskite derivatives, when the fraction of charged groups in the POEGMA block is about 5–25%. The charge fraction and the tethering of the ionic groups both play critical roles in driving the superlattice formation. This study highlights the accessibility of superlattice morphologies by introducing charges in a controlled manner.
Targeted removal of epigenetic barriers during transcriptional reprogramming
Authors: Baumann Valentin , Wiesbeck Maximilian , Breunig Christopher T. , Braun Julia M. , Köferle Anna , Ninkovic Jovica , Götz Magdalena , Stricker Stefan H. 
Published: May 2019

AbstractMaster transcription factors have the ability to direct and reverse cellular identities, and consequently their genes must be subject to particular transcriptional control. However, it is unclear which molecular processes are responsible for impeding their activation and safeguarding cellular identities. Here we show that the targeting of dCas9-VP64 to the promoter of the master transcription factor Sox1 results in strong transcript and protein up-regulation in neural progenitor cells (NPCs). This gene activation restores lost neuronal differentiation potential, which substantiates the role of Sox1 as a master transcription factor. However, despite efficient transactivator binding, major proportions of progenitor cells are unresponsive to the transactivating stimulus. By combining the transactivation domain with epigenome editing we find that among a series of euchromatic processes, the removal of DNA methylation (by dCas9-Tet1) has the highest potential to increase the proportion of cells activating foreign master transcription factors and thus breaking down cell identity barriers.
CD200R deletion promotes a neutrophil niche for Francisella tularensis and increases infectious burden and mortality
Authors: Casulli J. , Fife M. E. , Houston S. A. , Rossi S. , Dow J. , Williamson E. D. , Clark G. C , Hussell T. , D’Elia R. V. , Travis M. A 
Published: May 2019

AbstractPulmonary immune control is crucial for protection against pathogens. Here we identify a pathway that promotes host responses during pulmonary bacterial infection; the expression of CD200 receptor (CD200R), which is known to dampen pulmonary immune responses, promotes effective clearance of the lethal intracellular bacteriumFrancisella tularensis. We show that depletion of CD200R in mice increases in vitro and in vivo infectious burden. In vivo, CD200R deficiency leads to enhanced bacterial burden in neutrophils, suggesting CD200R normally limits the neutrophil niche for infection. Indeed, depletion of this neutrophil niche in CD200R−/−mice restoresF. tularensisinfection to levels seen in wild-type mice. Mechanistically, CD200R-deficient neutrophils display significantly reduced reactive oxygen species production (ROS), suggesting that CD200R-mediated ROS production in neutrophils is necessary for limitingF. tularensiscolonisation and proliferation. Overall, our data show that CD200R promotes the antimicrobial properties of neutrophils and may represent a novel antibacterial therapeutic target.
Covalent organic framework membranes through a mixed-dimensional assembly for molecular separations
Authors: Yang Hao , Yang Leixin , Wang Hongjian , Xu Ziang , Zhao Yumeng , Luo Yi , Nasir Nayab , Song Yimeng , Wu Hong , Pan Fusheng , Jiang Zhongyi 
Published: May 2019

AbstractCovalent organic frameworks (COFs) hold great promise in molecular separations owing to their robust, ordered and tunable porous network structures. Currently, the pore size of COFs is usually much larger than most small molecules. Meanwhile, the weak interlamellar interaction between COF nanosheets impedes the preparation of defect-free membranes. Herein, we report a series of COF membranes through a mixed-dimensional assembly of 2D COF nanosheets and 1D cellulose nanofibers (CNFs). The pore size of 0.45–1.0 nm is acquired from the sheltering effect of CNFs, rendering membranes precise molecular sieving ability, besides the multiple interactions between COFs and CNFs elevate membrane stability. Accordingly, the membranes exhibit a flux of 8.53 kg m−2h−1with a separation factor of 3876 for n-butanol dehydration, and high permeance of 42.8 L m−2h−1bar−1with a rejection of 96.8% for Na2SO4removal. Our mixed-dimensional design may inspire the fabrication and application of COF membranes.
A colloidal quantum dot infrared photodetector and its use for intraband detection
Authors: Livache Clément , Martinez Bertille , Goubet Nicolas , Gréboval Charlie , Qu Junling , Chu Audrey , Royer Sébastien , Ithurria Sandrine , Silly Mathieu G. , Dubertret Benoit , Lhuillier Emmanuel 
Published: May 2019

AbstractWavefunction engineering using intraband transition is the most versatile strategy for the design of infrared devices. To date, this strategy is nevertheless limited to epitaxially grown semiconductors, which lead to prohibitive costs for many applications. Meanwhile, colloidal nanocrystals have gained a high level of maturity from a material perspective and now achieve a broad spectral tunability. Here, we demonstrate that the energy landscape of quantum well and quantum dot infrared photodetectors can be mimicked from a mixture of mercury selenide and mercury telluride nanocrystals. This metamaterial combines intraband absorption with enhanced transport properties (i.e. low dark current, fast time response and large thermal activation energy). We also integrate this material into a photodiode with the highest infrared detection performances reported for an intraband-based nanocrystal device. This work demonstrates that the concept of wavefunction engineering at the device scale can now be applied for the design of complex colloidal nanocrystal-based devices.
Direct observation of atomic-scale fracture path within ceramic grain boundary core
Authors: Kondo Shun , Ishihara Akihito , Tochigi Eita , Shibata Naoya , Ikuhara Yuichi 
Published: May 2019

AbstractIn fracture processes, grain boundaries behave as preferential paths for crack propagation. These grain boundary fractures proceed by the atomic-bond rupture within the grain boundary cores, and thus grain boundary structures have crucial influence on the fracture properties. However, the relationship between grain boundary structures and atomic fracture processes has been a matter of conjecture, especially in the case of dopant-segregated grain boundaries which have complicated local structures and chemistries. Here, we determine the atomic-bond breaking path within a dopant-segregated Al2O3 grain boundary core, via atomic-scale observations of the as-fractured surface and the crack tip introduced by in situ nanoindentation experiments inside a transmission electron microscope. Our observations show that the atomic fracture path is selected to produce less coordination-deficient oxygen polyhedra of dopant cations, which is rationalised using first-principles calculations. The present findings indicate that the atomic coordination geometry at the grain boundary core affects the fracture processes.
High-mobility, trap-free charge transport in conjugated polymer diodes
Authors: Nikolka Mark , Broch Katharina , Armitage John , Hanifi David , Nowack Peer J. , Venkateshvaran Deepak , Sadhanala Aditya , Saska Jan , Mascal Mark , Jung Seok-Heon , Lee Jin‐Kyun , McCulloch Iain , Salleo Alberto , Sirringhaus Henning 
Published: May 2019

AbstractCharge transport in conjugated polymer semiconductors has traditionally been thought to be limited to a low-mobility regime by pronounced energetic disorder. Much progress has recently been made in advancing carrier mobilities in field-effect transistors through developing low-disorder conjugated polymers. However, in diodes these polymers have to date not shown much improved mobilities, presumably reflecting the fact that in diodes lower carrier concentrations are available to fill up residual tail states in the density of states. Here, we show that the bulk charge transport in low-disorder polymers is limited by water-induced trap states and that their concentration can be dramatically reduced through incorporating small molecular additives into the polymer film. Upon incorporation of the additives we achieve space-charge limited current characteristics that resemble molecular single crystals such as rubrene with high, trap-free SCLC mobilities up to 0.2 cm2/Vs and a width of the residual tail state distribution comparable to kBT.
A microbiota-generated bile salt induces biofilm formation in Clostridium difficile
Authors: Dubois Thomas , Tremblay Yannick D. N. , Hamiot Audrey , Martin-Verstraete Isabelle , Deschamps Julien , Monot Marc , Briandet Romain , Dupuy Bruno 
Published: May 2019

AbstractClostridium difficile is a major cause of nosocomial infections. Bacterial persistence in the gut is responsible for infection relapse; sporulation and other unidentified mechanisms contribute to this process. Intestinal bile salts cholate and deoxycholate stimulate spore germination, while deoxycholate kills vegetative cells. Here, we report that sub-lethal concentrations of deoxycholate stimulate biofilm formation, which protects C. difficile from antimicrobial compounds. The biofilm matrix is composed of extracellular DNA and proteinaceous factors that promote biofilm stability. Transcriptomic analysis indicates that deoxycholate induces metabolic pathways and cell envelope reorganization, and represses toxin and spore production. In support of the transcriptomic analysis, we show that global metabolic regulators and an uncharacterized lipoprotein contribute to deoxycholate-induced biofilm formation. Finally, Clostridium scindens enhances biofilm formation of C. difficile by converting cholate into deoxycholate. Together, our results suggest that deoxycholate is an intestinal signal that induces C. difficile persistence and may increase the risk of relapse.