bluuebunny/crossref_metadata_2025_split huggingface dataset:
Piezo-catalysis for nondestructive tooth whitening
Authors: Wang Yang , Wen Xinrong , Jia Yanmin , Huang Ming , Wang Feifei , Zhang Xuehui , Bai Yunyang , Yuan Guoliang , Wang Yaojin 
Published: March 2020

AbstractThe increasing demand for a whiter smile has resulted in an increased popularity for tooth whitening procedures. The most classic hydrogen peroxide-based whitening agents are effective, but can lead to enamel demineralization, gingival irritation, or cytotoxicity. Furthermore, these techniques are excessively time-consuming. Here, we report a nondestructive, harmless and convenient tooth whitening strategy based on a piezo-catalysis effect realized by replacement of abrasives traditionally used in toothpaste with piezoelectric particles. Degradation of organic dyes via piezo-catalysis of BaTiO3 (BTO) nanoparticles was performed under ultrasonic vibration to simulate daily tooth brushing. Teeth stained with black tea, blueberry juice, wine or a combination thereof can be notably whitened by the poled BTO turbid liquid after vibration for 3 h. A similar treatment using unpoled or cubic BTO show negligible tooth whitening effect. Furthermore, the BTO nanoparticle-based piezo-catalysis tooth whitening procedure exhibits remarkably less damage to both enamel and biological cells.
Perivascular localization of macrophages in the intestinal mucosa is regulated by Nr4a1 and the microbiome
Authors: Honda Masaki , Surewaard Bas G. J. , Watanabe Mayuki , Hedrick Catherine C. , Lee Woo-Yong , Brown Kirsty , McCoy Kathy D. , Kubes Paul 
Published: March 2020

AbstractWhile the ontogeny and recruitment of the intestinal monocyte/macrophage lineage has been studied extensively, their precise localization and function has been overlooked. Here we show by imaging the murine small and large intestines in steady-state that intestinal CX3CR1+ macrophages form an interdigitated network intimately adherent to the entire mucosal lamina propria vasculature. The macrophages form contacts with each other, which are disrupted in the absence of microbiome, monocyte recruitment (Ccr2−/−), or monocyte conversion (Nr4a1−/−). In dysbiosis, gaps exist between the perivascular macrophages correlating with increased bacterial translocation from the lamina propria into the bloodstream. The recruitment of monocytes and conversion to macrophages during intestinal injury is also dependent upon CCR2, Nr4a1 and the microbiome. These findings demonstrate a relationship between microbiome and the maturation of lamina propria perivascular macrophages into a tight anatomical barrier that might function to prevent bacterial translocation. These cells are also critical for emergency vascular repair.
Slow-to-fast transition of giant creeping rockslides modulated by undrained loading in basal shear zones
Authors: Agliardi Federico , Scuderi Marco M. , Fusi Nicoletta , Collettini Cristiano 
Published: March 2020

AbstractGiant rockslides are widespread and sensitive to hydrological forcing, especially in climate change scenarios. They creep slowly for centuries and then can fail catastrophically posing major threats to society. However, the mechanisms regulating the slow-to-fast transition toward their catastrophic collapse remain elusive. We couple laboratory experiments on natural rockslide shear zone material and in situ observations to provide a scale-independent demonstration that short-term pore fluid pressure variations originate a full spectrum of creep styles, modulated by slip-induced undrained conditions. Shear zones respond to pore pressure increments by impulsive acceleration and dilatancy, causing spontaneous deceleration followed by sustained steady-rate creep. Increasing pore pressure results in high creep rates and eventual collapse. Laboratory experiments quantitatively capture the in situ behavior of giant rockslides and lay physically-based foundations to understand the collapse of giant rockslides.
A receptor for the complement regulator factor H increases transmission of trypanosomes to tsetse flies
Authors: Macleod Olivia J. S. , Bart Jean-Mathieu , MacGregor Paula , Peacock Lori , Savill Nicholas J. , Hester Svenja , Ravel Sophie , Sunter Jack D. , Trevor Camilla , Rust Steven , Vaughan Tristan J. , Minter Ralph , Mohammed Shabaz , Gibson Wendy , Taylor Martin C. , Higgins Matthew K. , Carrington Mark 
Published: March 2020

AbstractPersistent pathogens have evolved to avoid elimination by the mammalian immune system including mechanisms to evade complement. Infections with African trypanosomes can persist for years and cause human and animal disease throughout sub-Saharan Africa. It is not known how trypanosomes limit the action of the alternative complement pathway. Here we identify an African trypanosome receptor for mammalian factor H, a negative regulator of the alternative pathway. Structural studies show how the receptor binds ligand, leaving inhibitory domains of factor H free to inactivate complement C3b deposited on the trypanosome surface. Receptor expression is highest in developmental stages transmitted to the tsetse fly vector and those exposed to blood meals in the tsetse gut. Receptor gene deletion reduced tsetse infection, identifying this receptor as a virulence factor for transmission. This demonstrates how a pathogen evolved a molecular mechanism to increase transmission to an insect vector by exploitation of a mammalian complement regulator.
Impact of the gut microbiota on the m6A epitranscriptome of mouse cecum and liver
Authors: Jabs Sabrina , Biton Anne , Bécavin Christophe , Nahori Marie-Anne , Ghozlane Amine , Pagliuso Alessandro , Spanò Giulia , Guérineau Vincent , Touboul David , Giai Gianetto Quentin , Chaze Thibault , Matondo Mariette , Dillies Marie-Agnès , Cossart Pascale 
Published: March 2020

AbstractThe intestinal microbiota modulates host physiology and gene expression via mechanisms that are not fully understood. Here we examine whether host epitranscriptomic marks are affected by the gut microbiota. We use methylated RNA-immunoprecipitation and sequencing (MeRIP-seq) to identify N6-methyladenosine (m6A) modifications in mRNA of mice carrying conventional, modified, or no microbiota. We find that variations in the gut microbiota correlate with m6A modifications in the cecum, and to a lesser extent in the liver, affecting pathways related to metabolism, inflammation and antimicrobial responses. We analyze expression levels of several known writer and eraser enzymes, and find that the methyltransferase Mettl16 is downregulated in absence of a microbiota, and one of its target mRNAs, encoding S-adenosylmethionine synthase Mat2a, is less methylated. We furthermore show thatAkkermansia muciniphilaandLactobacillus plantarumaffect specific m6A modifications in mono-associated mice. Our results highlight epitranscriptomic modifications as an additional level of interaction between commensal bacteria and their host.
Complex microparticle architectures from stimuli-responsive intrinsically disordered proteins
Authors: Roberts Stefan , Miao Vincent , Costa Simone , Simon Joseph , Kelly Garrett , Shah Tejank , Zauscher Stefan , Chilkoti Ashutosh 
Published: March 2020

AbstractThe controllable production of microparticles with complex geometries is useful for a variety of applications in materials science and bioengineering. The formation of intricate microarchitectures typically requires sophisticated fabrication techniques such as flow lithography or multiple-emulsion microfluidics. By harnessing the molecular interactions of a set of artificial intrinsically disordered proteins (IDPs), we have created complex microparticle geometries, including porous particles, core-shell and hollow shell structures, and a unique ‘fruits-on-a-vine’ arrangement, by exploiting the metastable region of the phase diagram of thermally responsive IDPs within microdroplets. Through multi-site unnatural amino acid (UAA) incorporation, these protein microparticles can also be photo-crosslinked and stably extracted to an all-aqueous environment. This work expands the functional utility of artificial IDPs as well as the available microarchitectures of this class of biocompatible IDPs, with potential applications in drug delivery and tissue engineering.
Electrical monitoring of photoisomerization of block copolymers intercalated into graphene sheets
Authors: Kim Semin , Le Thanh-Hai , Choi Yunseok , Lee Haney , Heo Eunseo , Lee Unhan , Kim Saerona , Chae Subin , Kim Yoong Ahm , Yoon Hyeonseok 
Published: March 2020

AbstractInsulating polymers have received little attention in electronic applications. Here, we synthesize a photoresponsive, amphiphilic block copolymer (PEO-b-PVBO) and further control the chain growth of the block segment (PVBO) to obtain different degrees of polymerization (DPs). The benzylidene oxazolone moiety in PEO-b-PVBO facilitated chain-conformational changes due to photoisomerization under visible/ultraviolet (UV) light illumination. Intercalation of the photoresponsive but electrically insulating PEO-b-PVBO into graphene sheets enabled electrical monitoring of the conformational change of the block copolymer at the molecular level. The current change at the microampere level was proportional to the DP of PVBO, demonstrating that the PEO-b-PVBO-intercalated graphene nanohybrid (PGNH) can be used in UV sensors. Additionally, discrete signals at the nanoampere level were separated from the first derivative of the time-dependent current using the fast Fourier transform (FFT). Analysis of the harmonic frequencies using the FFT revealed that the PGNH afforded sawtooth-type current flow mediated by Coulomb blockade oscillation.
Cryptochrome-mediated blue-light signalling modulates UVR8 photoreceptor activity and contributes to UV-B tolerance in Arabidopsis
Authors: Tissot Nicolas , Ulm Roman 
Published: March 2020

AbstractUV-B constitutes a critical part of the sunlight reaching the earth surface. The homodimeric plant UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8) monomerizes in response to UV-B and induces photomorphogenic responses, including UV-B acclimation and tolerance. REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1 (RUP1) and RUP2 are negative feedback regulators that operate by facilitating UVR8 ground state reversion through re-dimerization. Here we show that RUP1 and RUP2 are transcriptionally induced by cryptochrome photoreceptors in response to blue light, which is dependent on the bZIP transcriptional regulator ELONGATED HYPOCOTYL 5 (HY5). Elevated RUP1 and RUP2 levels under blue light enhance UVR8 re-dimerization, thereby negatively regulating UVR8 signalling and providing photoreceptor pathway cross-regulation in a polychromatic light environment, as is the case in nature. We further show that cryptochrome 1, as well as the red-light photoreceptor phytochrome B, contribute to UV-B tolerance redundantly with UVR8. Thus, photoreceptors for both visible light and UV-B regulate UV-B tolerance through an intricate interplay allowing the integration of diverse sunlight signals.
FAM111A protects replication forks from protein obstacles via its trypsin-like domain
Authors: Kojima Yusuke , Machida Yuka , Palani Sowmiya , Caulfield Thomas R. , Radisky Evette S. , Kaufmann Scott H. , Machida Yuichi J. 
Published: March 2020

AbstractPersistent protein obstacles on genomic DNA, such as DNA-protein crosslinks (DPCs) and tight nucleoprotein complexes, can block replication forks. DPCs can be removed by the proteolytic activities of the metalloprotease SPRTN or the proteasome in a replication-coupled manner; however, additional proteolytic mechanisms may exist to cope with the diversity of protein obstacles. Here, we show that FAM111A, a PCNA-interacting protein, plays an important role in mitigating the effect of protein obstacles on replication forks. This function of FAM111A requires an intact trypsin-like protease domain, the PCNA interaction, and the DNA-binding domain that is necessary for protease activity in vivo. FAM111A, but not SPRTN, protects replication forks from stalling at poly(ADP-ribose) polymerase 1 (PARP1)-DNA complexes trapped by PARP inhibitors, thereby promoting cell survival after drug treatment. Altogether, our findings reveal a role of FAM111A in overcoming protein obstacles to replication forks, shedding light on cellular responses to anti-cancer therapies.
SSRP1-mediated histone H1 eviction promotes replication origin assembly and accelerated development
Authors: Falbo Lucia , Raspelli Erica , Romeo Francesco , Fiorani Simona , Pezzimenti Federica , Casagrande Francesca , Costa Ilaria , Parazzoli Dario , Costanzo Vincenzo 
Published: March 2020

AbstractIn several metazoans, the number of active replication origins in embryonic nuclei is higher than in somatic ones, ensuring rapid genome duplication during synchronous embryonic cell divisions. High replication origin density can be restored by somatic nuclear reprogramming. However, mechanisms underlying high replication origin density formation coupled to rapid cell cycles are poorly understood. Here, using Xenopus laevis, we show that SSRP1 stimulates replication origin assembly on somatic chromatin by promoting eviction of histone H1 through its N-terminal domain. Histone H1 removal derepresses ORC and MCM chromatin binding, allowing efficient replication origin assembly. SSRP1 protein decays at mid-blastula transition (MBT) when asynchronous somatic cell cycles start. Increasing levels of SSRP1 delay MBT and, surprisingly, accelerate post-MBT cell cycle speed and embryo development. These findings identify a major epigenetic mechanism regulating DNA replication and directly linking replication origin assembly, cell cycle duration and embryo development in vertebrates.
Lipidomic and biophysical homeostasis of mammalian membranes counteracts dietary lipid perturbations to maintain cellular fitness
Authors: Levental Kandice R. , Malmberg Eric , Symons Jessica L. , Fan Yang-Yi , Chapkin Robert S. , Ernst Robert , Levental Ilya 
Published: March 2020

AbstractProper membrane physiology requires maintenance of biophysical properties, which must be buffered from external perturbations. While homeostatic adaptation of membrane fluidity to temperature variation is a ubiquitous feature of ectothermic organisms, such responsive membrane adaptation to external inputs has not been directly observed in mammals. Here, we report that challenging mammalian membranes by dietary lipids leads to robust lipidomic remodeling to preserve membrane physical properties. Specifically, exogenous polyunsaturated fatty acids are rapidly incorporated into membrane lipids, inducing a reduction in membrane packing. These effects are rapidly compensated both in culture and in vivo by lipidome-wide remodeling, most notably upregulation of saturated lipids and cholesterol, resulting in recovery of membrane packing and permeability. Abrogation of this response results in cytotoxicity when membrane homeostasis is challenged by dietary lipids. These results reveal an essential mammalian mechanism for membrane homeostasis wherein lipidome remodeling in response to dietary lipid inputs preserves functional membrane phenotypes.
Boron-mediated directed aromatic C–H hydroxylation
Authors: Lv Jiahang , Zhao Binlin , Yuan Yu , Han Ying , Shi Zhuangzhi 
Published: March 2020

AbstractTransition metal-catalysed C–H hydroxylation is one of the most notable advances in synthetic chemistry during the past few decades and it has been widely employed in the preparation of alcohols and phenols. The site-selective hydroxylation of aromatic C–H bonds under mild conditions, especially in the context of substituted (hetero)arenes with diverse functional groups, remains a challenge. Here, we report a general and mild chelation-assisted C–H hydroxylation of (hetero)arenes mediated by boron species without the use of any transition metals. Diverse (hetero)arenes bearing amide directing groups can be utilized for ortho C–H hydroxylation under mild reaction conditions and with broad functional group compatibility. Additionally, this transition metal-free strategy can be extended to synthesize C7 and C4-hydroxylated indoles. By utilizing the present method, the formal synthesis of several phenol intermediates to bioactive molecules is demonstrated.
The genetic architecture of breast papillary lesions as a predictor of progression to carcinoma
Authors: Kader Tanjina , Elder Kenneth , Zethoven Magnus , Semple Timothy , Hill Prue , Goode David L. , Thio Niko , Cheasley Dane , Rowley Simone M. , Byrne David J. , Pang Jia-Min , Miligy Islam M. , Green Andrew R. , Rakha Emad A. , Fox Stephen B. , Mann G. Bruce , Campbell Ian G. , Gorringe Kylie L. 
Published: March 2020

AbstractIntraductal papillomas (IDP) are challenging breast findings because of their variable risk of progression to malignancy. The molecular events driving IDP development and genomic features of malignant progression are poorly understood. In this study, genome-wide CNA and/or targeted mutation analysis was performed on 44 cases of IDP, of which 20 cases had coexisting ductal carcinoma in situ (DCIS), papillary DCIS or invasive ductal carcinoma (IDC). CNA were rare in pure IDP, but 69% carried an activatingPIK3CAmutation. Among the synchronous IDP cases, 55% (11/20) were clonally related to the synchronous DCIS and/or IDC, only one of which had papillary histology. In contrast to pure IDP,PIK3CAmutations were absent from clonal cases. CNAs in any of chromosomes 1, 16 or 11 were significantly enriched in clonal IDP lesions compared to pure and non-clonal IDP. The observation that 55% of IDP are clonal to DCIS/IDC indicates that IDP can be a direct precursor for breast carcinoma, not limited to the papillary type. The absence ofPIK3CAmutations and presence of CNAs in IDP could be used clinically to identify patients at high risk of progression to carcinoma.
Tuneable topological domain wall states in engineered atomic chains
Authors: Huda Md Nurul , Kezilebieke Shawulienu , Ojanen Teemu , Drost Robert , Liljeroth Peter 
Published: March 2020

AbstractTopological modes in one- and two-dimensional systems have been proposed for numerous applications utilizing their exotic electronic responses. The 1D, zero-energy, topologically protected end modes can be realized in structures implementing the Su–Schrieffer–Heeger (SSH) model. While the edge modes in the SSH model are at exactly the mid-gap energy, other paradigmatic 1D models such as trimer and coupled dimer chains have non-zero energy boundary states. However, these structures have not been realized in an atomically tuneable system that would allow explicit control of the edge modes. Here, we demonstrate atomically controlled trimer and coupled dimer chains realized using chlorine vacancies in the c(2 × 2) adsorption layer on Cu(100). This system allows wide tuneability of the domain wall modes that we experimentally demonstrate using low-temperature scanning tunneling microscopy (STM).
An optimized purified inactivated Zika vaccine provides sustained immunogenicity and protection in cynomolgus macaques
Authors: Lecouturier Valérie , Pavot Vincent , Berry Catherine , Donadieu Arnaud , de Montfort Aymeric , Boudet Florence , Rokbi Bachra , Jackson Nicolas , Heinrichs Jon 
Published: March 2020

AbstractThe recent spread of Zika virus (ZIKV) through the Americas and Caribbean and its devastating consequences for pregnant women and their babies have driven the search for a safe and efficacious ZIKV vaccine. Among the vaccine candidates, a first-generation ZIKV purified inactivated vaccine (ZPIV), adjuvanted with aluminum hydroxide, developed by the Walter Reed Army Institute of Research (WRAIR), has elicited high seroconversion rates in participants in three phase-I clinical trials. In collaboration with the WRAIR, Sanofi Pasteur (SP) optimized the production scale, culture and purification conditions, and increased the regulatory compliance, both of which are critical for clinical development and licensure of this vaccine. Using a clinical batch of the first-generation ZPIV as a benchmark, we report that different doses of the optimized vaccine (ZPIV-SP) elicited sustained neutralizing antibodies, specific T- and memory B-cells, and provided complete protection against a ZIKV challenge in cynomolgus macaques. These data provide evidence that the ZPIV-SP vaccine performs at least as well as the ZPIV vaccine, and provide support for continued development in the event of future ZIKV outbreaks.
BCG and BCGΔBCG1419c protect type 2 diabetic mice against tuberculosis via different participation of T and B lymphocytes, dendritic cells and pro-inflammatory cytokines
Authors: Segura-Cerda Cristian Alfredo , Marquina-Castillo Brenda , Lozano-Ordaz Vasti , Mata-Espinosa Dulce , Barrios-Payán Jorge Alberto , López-Torres Manuel O. , Aceves-Sánchez Michel de Jesús , Bielefeldt-Ohmann Helle , Hernández-Pando Rogelio , Flores-Valdez Mario Alberto 
Published: March 2020

AbstractComorbidity between Tuberculosis (TB) and type 2 diabetes (T2D) is one of the greatest contributors to the spread ofMycobacterium tuberculosis (M. tuberculosis)in low- and middle-income countries. T2D compromises key steps of immune responses againstM. tuberculosisand it might affect the protection afforded by vaccine candidates against TB. We compared the protection and immune response afforded by the BCGΔBCG1419c vaccine candidate versus that of wild-type BCG in mice with T2D. Vaccination with both BCGΔBCG1419c, BCG or infection withM. tuberculosisreduced weight loss, hyperglycemia, and insulin resistance during T2D progression, suggesting that metabolic changes affecting these parameters were affected by mycobacteria. For control of acute TB, and compared with non-vaccinated controls, BCG showed a dominant T CD4+response whereas BCGΔBCG1419c showed a dominant T CD8+/B lymphocyte response. Moreover, BCG maintained an increased response in lung cells via IFN-γ, TNF-α, and IL-4, while BCGΔBCG1419c increased IFN-γ but reduced IL-4 production. As for chronic TB, and compared with non-vaccinated controls, both BCG strains had a predominant presence of T CD4+lymphocytes. In counterpart, BCGΔBCG1419c led to increased presence of dendritic cells and an increased production of IL-1 β. Overall, while BCG effectively reduced pneumonia in acute infection, it failed to reduce it in chronic infection, whereas we hypothesize that increased production of IL-1 β induced by BCGΔBCG1419c contributed to reduced pneumonia and alveolitis in chronic TB. Our results show that BCG and BCGΔBCG1419c protect T2D mice against TB via different participation of T and B lymphocytes, dendritic cells, and pro-inflammatory cytokines.