bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental colitis in SIV-uninfected rhesus macaques recapitulates important features of pathogenic SIV infection
Authors: Hao Xing Pei , Lucero Carissa M. , Turkbey Baris , Bernardo Marcelino L. , Morcock David R. , Deleage Claire , Trubey Charles M. , Smedley Jeremy , Klatt Nichole R. , Giavedoni Luis D. , Kristoff Jan , Xu Amy , Del Prete Gregory Q. , Keele Brandon F. , Rao Srinivas S. , Alvord W. Gregory , Choyke Peter L. , Lifson Jeffrey D. , Brenchley Jason M. , Apetrei Cristian , Pandrea Ivona , Estes Jacob D. 
Published: August 2015

AbstractMucosal damage to the gastrointestinal (GI) tract with resulting microbial translocation is hypothesized to significantly contribute to the heightened and persistent chronic inflammation and immune activation characteristic to HIV infection. Here we employ a non-human primate model of chemically induced colitis in SIV-uninfected rhesus macaques that we developed using dextran sulfate sodium (DSS), to directly test this hypothesis. DSS treatment results in GI barrier damage with associated microbial translocation, inflammation and immune activation. The progression and severity of colitis are longitudinally monitored by a magnetic resonance imaging approach. DSS treatment of SIV-infected African green monkeys, a natural host species for SIV that does not manifest GI tract damage or chronic immune activation during infection, results in colitis with elevated levels of plasma SIV RNA, sCD14, LPS, CRP and mucosal CD4+ T-cell loss. Together these results support the hypothesis that GI tract damage leading to local and systemic microbial translocation, and associated immune activation, are important determinants of AIDS pathogenesis.
Adhesive curing through low-voltage activation
Authors: Ping Jianfeng , Gao Feng , Chen Jian Lin , Webster Richard D. , Steele Terry W. J. 
Published: August 2015

AbstractInstant curing adhesives typically fall within three categories, being activated by either light (photocuring), heat (thermocuring) or chemical means. These curing strategies limit applications to specific substrates and can only be activated under certain conditions. Here we present the development of an instant curing adhesive through low-voltage activation. The electrocuring adhesive is synthesized by grafting carbene precursors on polyamidoamine dendrimers and dissolving in aqueous solvents to form viscous gels. The electrocuring adhesives are activated at −2 V versus Ag/AgCl, allowing tunable crosslinking within the dendrimer matrix and on both electrode surfaces. As the applied voltage discontinued, crosslinking immediately terminated. Thus, crosslinking initiation and propagation are observed to be voltage and time dependent, enabling tuning of both material properties and adhesive strength. The electrocuring adhesive has immediate implications in manufacturing and development of implantable bioadhesives.
Stoichiometry for α-bungarotoxin block of α7 acetylcholine receptors
Authors: daCosta Corrie J. B. , Free Chris R. , Sine Steven M. 
Published: August 2015

Abstractα-Bungarotoxin (α-Btx) binds to the five agonist binding sites on the homopentameric α7-acetylcholine receptor, yet the number of bound α-Btx molecules required to prevent agonist-induced channel opening remains unknown. To determine the stoichiometry for α-Btx blockade, we generate receptors comprised of wild-type and α-Btx-resistant subunits, tag one of the subunit types with conductance mutations to report subunit stoichiometry, and following incubation with α-Btx, monitor opening of individual receptor channels with defined subunit stoichiometry. We find that a single α-Btx-sensitive subunit confers nearly maximal suppression of channel opening, despite four binding sites remaining unoccupied by α-Btx and accessible to the agonist. Given structural evidence that α-Btx locks the agonist binding site in an inactive conformation, we conclude that the dominant mechanism of antagonism is non-competitive, originating from conformational arrest of the binding sites, and that the five α7 subunits are interdependent and maintain conformational symmetry in the open channel state.
Sustaining dry surfaces under water
Authors: Jones Paul R. , Hao Xiuqing , Cruz-Chu Eduardo R. , Rykaczewski Konrad , Nandy Krishanu , Schutzius Thomas M. , Varanasi Kripa K. , Megaridis Constantine M. , Walther Jens H. , Koumoutsakos Petros , Espinosa Horacio D. , Patankar Neelesh A. 
Published: August 2015

AbstractRough surfaces immersed under water remain practically dry if the liquid-solid contact is on roughness peaks, while the roughness valleys are filled with gas. Mechanisms that prevent water from invading the valleys are well studied. However, to remain practically dry under water, additional mechanisms need consideration. This is because trapped gas (e.g. air) in the roughness valleys can dissolve into the water pool, leading to invasion. Additionally, water vapor can also occupy the roughness valleys of immersed surfaces. If water vapor condenses, that too leads to invasion. These effects have not been investigated and are critically important to maintain surfaces dry under water. In this work, we identify the critical roughness scale, below which it is possible to sustain the vapor phase of water and/or trapped gases in roughness valleys – thus keeping the immersed surface dry. Theoretical predictions are consistent with molecular dynamics simulations and experiments.
Whole-genome sequencing reveals the effect of vaccination on the evolution of Bordetella pertussis
Authors: Xu Yinghua , Liu Bin , Gröndahl-Yli-Hannuksila Kirsi , Tan Yajun , Feng Lu , Kallonen Teemu , Wang Lichan , Peng Ding , He Qiushui , Wang Lei , Zhang Shumin 
Published: August 2015

AbstractHerd immunity can potentially induce a change of circulating viruses. However, it remains largely unknown that how bacterial pathogens adapt to vaccination. In this study, Bordetella pertussis, the causative agent of whooping cough, was selected as an example to explore possible effect of vaccination on the bacterial pathogen. We sequenced and analysed the complete genomes of 40 B. pertussis strains from Finland and China, as well as 11 previously sequenced strains from the Netherlands, where different vaccination strategies have been used over the past 50 years. The results showed that the molecular clock moved at different rates in these countries and in distinct periods, which suggested that evolution of the B. pertussis population was closely associated with the country vaccination coverage. Comparative whole-genome analyses indicated that evolution in this human-restricted pathogen was mainly characterised by ongoing genetic shift and gene loss. Furthermore, 116 SNPs were specifically detected in currently circulating ptxP3-containing strains. The finding might explain the successful emergence of this lineage and its spread worldwide. Collectively, our results suggest that the immune pressure of vaccination is one major driving force for the evolution of B. pertussis, which facilitates further exploration of the pathogenicity of B. pertussis.
Structural basis for the neutralization of MERS-CoV by a human monoclonal antibody MERS-27
Authors: Yu Xiaojuan , Zhang Senyan , Jiang Liwei , Cui Ye , Li Dongxia , Wang Dongli , Wang Nianshuang , Fu Lili , Shi Xuanlin , Li Ziqiang , Zhang Linqi , Wang Xinquan 
Published: August 2015

AbstractThe recently reported Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe respiratory illness in humans with an approximately 30% mortality rate. The envelope spike glycoprotein on the surface of MERS-CoV mediates receptor binding, membrane fusion and viral entry. We previously reported two human monoclonal antibodies that target the receptor binding domain (RBD) of the spike and exhibit strong neutralization activity against live and pesudotyped MERS-CoV infection. Here we determined the crystal structure of MERS-CoV RBD bound to the Fab fragment of MERS-27 antibody at 3.20 Å resolution. The MERS-27 epitope in the RBD overlaps with the binding site of the MERS-CoV receptor DPP4. Further biochemical, viral entry and neutralization analyses identified two critical residues in the RBD for both MERS-27 recognition and DPP4 binding. One of the residues, Trp535, was found to function as an anchor residue at the binding interface with MERS-27. Upon receptor binding, Trp535 interacts with the N-linked carbohydrate moiety of DPP4. Thus, MERS-27 inhibits MERS-CoV infection by directly blocking both protein-protein and protein-carbohydrate interactions between MERS-CoV RBD and DPP4. These results shed light on the molecular basis of MERS-27 neutralization and will assist in the optimization of MERS-27 as a tool to combat MERS-CoV infection.
Conjugates of γ-Carbolines and Phenothiazine as new selective inhibitors of butyrylcholinesterase and blockers of NMDA receptors for Alzheimer Disease
Authors: Makhaeva Galina F. , Lushchekina Sofya V. , Boltneva Natalia P. , Sokolov Vladimir B. , Grigoriev Vladimir V. , Serebryakova Olga G. , Vikhareva Ekaterina A. , Aksinenko Alexey Yu. , Barreto George E. , Aliev Gjumrakch , Bachurin Sergey O. 
Published: August 2015

AbstractAlzheimer disease is a multifactorial pathology and the development of new multitarget neuroprotective drugs is promising and attractive. We synthesized a group of original compounds, which combine in one molecule γ-carboline fragment of dimebon and phenothiazine core of methylene blue (MB) linked by 1-oxo- and 2-hydroxypropylene spacers. Inhibitory activity of the conjugates toward acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and structurally close to them carboxylesterase (CaE), as well their binding to NMDA-receptors were evaluated in vitro and in silico. These newly synthesized compounds showed significantly higher inhibitory activity toward BChE with IC50 values in submicromolar and micromolar range and exhibited selective inhibitory action against BChE over AChE and CaE. Kinetic studies for the 9 most active compounds indicated that majority of them were mixed-type BChE inhibitors. The main specific protein-ligand interaction is π-π stacking of phenothiazine ring with indole group of Trp82. These compounds emerge as promising safe multitarget ligands for the further development of a therapeutic approach against aging-related neurodegenerative disorders such as Alzheimer and/or other pathological conditions.
Vapor-Driven Propulsion of Catalytic Micromotors
Authors: Dong Renfeng , Li Jinxing , Rozen Isaac , Ezhilan Barath , Xu Tailin , Christianson Caleb , Gao Wei , Saintillan David , Ren Biye , Wang Joseph 
Published: August 2015

AbstractChemically-powered micromotors offer exciting opportunities in diverse fields, including therapeutic delivery, environmental remediation and nanoscale manufacturing. However, these nanovehicles require direct addition of high concentration of chemical fuel to the motor solution for their propulsion. We report the efficient vapor-powered propulsion of catalytic micromotors without direct addition of fuel to the micromotor solution. Diffusion of hydrazine vapor from the surrounding atmosphere into the sample solution is instead used to trigger rapid movement of iridium-gold Janus microsphere motors. Such operation creates a new type of remotely-triggered and powered catalytic micro/nanomotors that are responsive to their surrounding environment. This new propulsion mechanism is accompanied by unique phenomena, such as the distinct off-on response to the presence of fuel in the surrounding atmosphere and spatio-temporal dependence of the motor speed borne out of the concentration gradient evolution within the motor solution. The relationship between the motor speed and the variables affecting the fuel concentration distribution is examined using a theoretical model for hydrazine transport, which is in turn used to explain the observed phenomena. The vapor-powered catalytic micro/nanomotors offer new opportunities in gas sensing, threat detection and environmental monitoring and open the door for a new class of environmentally-triggered micromotors.
Insertion of N2 into the Channels of AFI Zeolite under High Pressure
Authors: Lv Hang , yao Mingguang , Li Quanjun , Liu Ran , Liu Bo , Yao Zhen , Liu Dedi , Liu Zhaodong , Liu Jing , Chen Zhiqiang , Zou Bo , Cui Tian , Liu Bingbing 
Published: August 2015

AbstractWe present an experimental study of a new hybrid material where nitrogen is encapsulated in the channels of porous zeolite AlPO4-5 (AFI) single crystals by a high-pressure method. The high-pressure behavior of nitrogen confined inside the AFI nano-channels is then investigated by Raman spectroscopy up to 44 GPa. Under pressure, the Raman modes of confined nitrogen show behaviors different from those of the bulk nitrogen. After the return to atmospheric pressure, it is demonstrated that non-gaseous nitrogen can be effectively stabilized by being confined inside the intact AFI sample. This result provides new insight into nitrogen capture and storage technologies.
Laser-wakefield accelerators as hard x-ray sources for 3D medical imaging of human bone
Authors: Cole J. M. , Wood J. C. , Lopes N. C. , Poder K. , Abel R. L. , Alatabi S. , Bryant J. S. J. , Jin A. , Kneip S. , Mecseki K. , Symes D. R. , Mangles S. P. D. , Najmudin Z. 
Published: August 2015

AbstractA bright μm-sized source of hard synchrotron x-rays (critical energy Ecrit > 30 keV) based on the betatron oscillations of laser wakefield accelerated electrons has been developed. The potential of this source for medical imaging was demonstrated by performing micro-computed tomography of a human femoral trabecular bone sample, allowing full 3D reconstruction to a resolution below 50 μm. The use of a 1 cm long wakefield accelerator means that the length of the beamline (excluding the laser) is dominated by the x-ray imaging distances rather than the electron acceleration distances. The source possesses high peak brightness, which allows each image to be recorded with a single exposure and reduces the time required for a full tomographic scan. These properties make this an interesting laboratory source for many tomographic imaging applications.
Virulence from vesicles: Novel mechanisms of host cell injury by Escherichia coli O104:H4 outbreak strain
Authors: Kunsmann Lisa , Rüter Christian , Bauwens Andreas , Greune Lilo , Glüder Malte , Kemper Björn , Fruth Angelika , Wai Sun Nyunt , He Xiaohua , Lloubes Roland , Schmidt M. Alexander , Dobrindt Ulrich , Mellmann Alexander , Karch Helge , Bielaszewska Martina 
Published: August 2015

AbstractThe highly virulent Escherichia coli O104:H4 that caused the large 2011 outbreak of diarrhoea and haemolytic uraemic syndrome secretes blended virulence factors of enterohaemorrhagic and enteroaggregative E. coli, but their secretion pathways are unknown. We demonstrate that the outbreak strain releases a cocktail of virulence factors via outer membrane vesicles (OMVs) shed during growth. The OMVs contain Shiga toxin (Stx) 2a, the major virulence factor of the strain, Shigella enterotoxin 1, H4 flagellin and O104 lipopolysaccharide. The OMVs bind to and are internalised by human intestinal epithelial cells via dynamin-dependent and Stx2a-independent endocytosis, deliver the OMV-associated virulence factors intracellularly and induce caspase-9-mediated apoptosis and interleukin-8 secretion. Stx2a is the key OMV component responsible for the cytotoxicity, whereas flagellin and lipopolysaccharide are the major interleukin-8 inducers. The OMVs represent novel ways for the E. coli O104:H4 outbreak strain to deliver pathogenic cargoes and injure host cells.
Seed bank characteristics of the Nymphoides peltata population in Lake Taihu
Authors: Huang Wei , Chen Qiuwen , Chen Kaining 
Published: August 2015

AbstractThe Nymphoides peltata (N. peltata) population has shown rapid expansion in Lake Taihu, China, in recent years. The core question is whether N. peltata seeds have contributed to the expansion. To address this, we randomly selected three N. peltata stands to investigate the seed bank characteristics of N. peltata in Lake Taihu. Results showed that N. peltata had high seed production, with a maximum seed yield of 1763 seeds per m2. Density of intact and fragmented seeds decreased rapidly with sediment depth. Few intact or fragmented seeds were distributed at depths greater than 4 cm in the sediment. Spatial distribution of the seed bank indicated that most seeds sank to the sediment within the N. peltata stands and few seeds took advantage of their floating ability. Seeds recovered from the sediment during April to June had a low germination rate and no seeds germinated during October to April. Cold exposure treatment increased the germination rate remarkably. No seedlings were found in the field from January 2012 to December 2012, indicating that few seeds were successfully established in the surveyed area. The results suggested that sexual reproduction had little direct contribution to the N. peltata expansion in this large shallow lake.
Systemic modeling myeloma-osteoclast interactions under normoxic/hypoxic condition using a novel computational approach
Authors: Ji Zhiwei , Wu Dan , Zhao Weiling , Peng Huiming , Zhao Shengjie , Huang Deshuang , Zhou Xiaobo 
Published: August 2015

AbstractInteraction of myeloma cells with osteoclasts (OC) can enhance tumor cell expansion through activation of complex signaling transduction networks. Both cells reside in the bone marrow, a hypoxic niche. How OC-myeloma interaction in a hypoxic environment affects myeloma cell growth and their response to drug treatment is poorly understood. In this study, we i) cultured myeloma cells in the presence/absence of OCs under normoxia and hypoxia conditions and did protein profiling analysis using reverse phase protein array; ii) computationally developed an Integer Linear Programming approach to infer OC-mediated myeloma cell-specific signaling pathways under normoxic and hypoxic conditions. Our modeling analysis indicated that in the presence OCs, (1) cell growth-associated signaling pathways, PI3K/AKT and MEK/ERK, were activated and apoptotic regulatory proteins, BAX and BIM, down-regulated under normoxic condition; (2) β1 Integrin/FAK signaling pathway was activated in myeloma cells under hypoxic condition. Simulation of drug treatment effects by perturbing the inferred cell-specific pathways showed that targeting myeloma cells with the combination of PI3K and integrin inhibitors potentially (1) inhibited cell proliferation by reducing the expression/activation of NF-κB, S6, c-Myc and c-Jun under normoxic condition; (2) blocked myeloma cell migration and invasion by reducing the expression of FAK and PKC under hypoxic condition.
ABCG2 transporter inhibitor restores the sensitivity of triple negative breast cancer cells to aminolevulinic acid-mediated photodynamic therapy
Authors: Palasuberniam Pratheeba , Yang Xue , Kraus Daniel , Jones Patrick , Myers Kenneth A. , Chen Bin 
Published: August 2015

AbstractPhotosensitizer protoporphyrin IX (PpIX) fluorescence, intracellular localization and cell response to photodynamic therapy (PDT) were analyzed in MCF10A normal breast epithelial cells and a panel of human breast cancer cells including estrogen receptor (ER) positive, human epidermal growth factor receptor 2 (HER2) positive and triple negative breast cancer (TNBC) cells after treatment with PpIX precursor aminolevulinic acid (ALA). Although PpIX fluorescence was heterogeneous in different cells, TNBC cells showed significantly lower PpIX level than MCF10A and ER- or HER2-positive cells. PpIX fluorescence in TNBC cells also had much less mitochondrial localization than other cells. There was an inverse correlation between PpIX fluorescence and cell viability after PDT. Breast cancer cells with the highest PpIX fluorescence were the most sensitive to ALA-PDT and TNBC cells with the lowest PpIX level were resistant to PDT. Treatment of TNBC cells with ABCG2 transporter inhibitor Ko143 significantly increased ALA-PpIX fluorescence, enhanced PpIX mitochondrial accumulation and sensitized cancer cells to ALA-PDT. Ko143 treatment had little effect on PpIX production and ALA-PDT in normal and ER- or HER2-positive cells. These results demonstrate that enhanced ABCG2 activity renders TNBC cell resistance to ALA-PDT and inhibiting ABCG2 transporter is a promising approach for targeting TNBC with ALA-based modality.
Identification of miR-200a as a novel suppressor of connexin 43 in breast cancer cells
Authors: Ming Jia , Zhou Yan , Du Junze , Fan Shenghao , Pan Beibei , Wang Yinhuan , Fan Lingjun , Jiang Jun 
Published: August 2015

Both miRNAs (miRs) and connexin 43 (Cx43) were important regulators of the metastasis of breast cancer, whereas the miRs regulating Cx43 expression in breast cancer cells were still obscure. In the present study, we scanned and found miR-1, miR-206, miR-200a, miR-381, miR-23a/b and miR-186 were functional suppressors of human Cx43 mRNA and protein expression. Specially, we demonstrated that only miR-200a could directly target the 3′-untranslated region (3′-UTR) of human Cx43 gene. Functionally, overexpression of Cx43 in MCF cells potentiated the migration activity, whereas additional miR-200a treatment notably prevented this effect. Finally, we demonstrated that decreased levels of miR-200a and elevated expression of Cx43 in the metastatic breast cancer tissues compared with the primary ones. Thus, we are the first to identify miR-200a as a novel and direct suppressor of human Cx43, indicating that miR200a/Cx43 axis might be a useful diagnostic and therapeutic target of metastatic breast cancer.
New approach for optimal electricity planning and dispatching with hourly time-scale air quality and health considerations
Authors: Kerl Paul Y. , Zhang Wenxian , Moreno-Cruz Juan B. , Nenes Athanasios , Realff Matthew J. , Russell Armistead G. , Sokol Joel , Thomas Valerie M. 
Published: August 2015

Significance
The production of electricity from coal, natural gas, petroleum, and biomass releases air pollutants with significant impacts on ecosystems and human health. Pollutant exposure depends not only on the pollutant source emissions rate and the relative location of the power plant to population centers but also on temperature, wind velocity, and other atmospheric conditions, all of which vary by hour, day, and season. We have developed a method to evaluate fluctuating pollutant formation from source emissions, which we integrate within an electricity production model. In a case study of the state of Georgia from 2004 to 2011, we show how to reduce air pollutants and health impacts by shifting production among plants during a select number of hourly periods.
Neural microgenesis of personally familiar face recognition
Authors: Ramon Meike , Vizioli Luca , Liu-Shuang Joan , Rossion Bruno 
Published: August 2015

SignificanceWe addressed the open question of how the human brain recognizes personally familiar faces. A dynamic visual-stimulation paradigm revealed that familiar face recognition is achieved first and foremost in medial and anterior temporal regions of the extended face-processing system. These regions, including the amygdala, respond categorically to individual familiar faces. In contrast, activation in posterior core face-preferential regions is associated with the amount of visual information available, irrespective of familiarity. Through integration of core and extended face-processing systems, these observations provide a common framework for understanding the neural basis of familiar face recognition.