bluuebunny/crossref_metadata_2025_split huggingface dataset:
Creation of vortices by torque in multidimensional media with inhomogeneous defocusing nonlinearity
Authors: Driben Rodislav , Meier Torsten , Malomed Boris A. 
Published: March 2015

AbstractRecently, a new class of nonlinear systems was introduced, in which the self-trapping of fundamental and vortical localized modes in space of dimension D is supported by cubic self-repulsion with a strength growing as a function of the distance from the center, r, at any rate faster that rD. These systems support robust 2D and 3D modes which either do not exist or are unstable in other nonlinear systems. Here we demonstrate a possibility to create solitary vortices in this setting by applying a phase-imprinting torque to the ground state. Initially, a strong torque completely destroys the ground state. However, contrary to usual systems, where the destruction is irreversible, the present ones demonstrate a rapid restabilization and the creation of one or several shifted vortices orbiting the center. For the sake of comparison, we show analytically that, in the linear system with a 3D trapping potential, the action of a torque on the ground state is inefficient and creates only even-vorticity states with a small probability.
Selectivity control in Pt-catalyzed cinnamaldehyde hydrogenation
Authors: Durndell Lee J. , Parlett Christopher M. A. , Hondow Nicole S. , Isaacs Mark A. , Wilson Karen , Lee Adam F. 
Published: March 2015

AbstractChemoselectivity is a cornerstone of catalysis, permitting the targeted modification of specific functional groups within complex starting materials. Here we elucidate key structural and electronic factors controlling the liquid phase hydrogenation of cinnamaldehyde and related benzylic aldehydes over Pt nanoparticles. Mechanistic insight from kinetic mapping reveals cinnamaldehyde hydrogenation is structure-insensitive over metallic platinum, proceeding with a common Turnover Frequency independent of precursor, particle size or support architecture. In contrast, selectivity to the desired cinnamyl alcohol product is highly structure sensitive, with large nanoparticles and high hydrogen pressures favoring C = O over C = C hydrogenation, attributed to molecular surface crowding and suppression of sterically-demanding adsorption modes. In situ vibrational spectroscopies highlight the role of support polarity in enhancing C = O hydrogenation (through cinnamaldehyde reorientation), a general phenomenon extending to alkyl-substituted benzaldehydes. Tuning nanoparticle size and support polarity affords a flexible means to control the chemoselective hydrogenation of aromatic aldehydes.
HPIP is upregulated in colorectal cancer and regulates colorectal cancer cell proliferation, apoptosis and invasion
Authors: Feng Yingying , Xu Xiaojie , Zhang Yunjing , Ding Jianhua , Wang Yonggang , Zhang Xiaopeng , Wu Zhe , Kang Lei , Liang Yingchun , Zhou LiYing , Song Santai , Zhao Ke , Ye Qinong 
Published: March 2015

AbstractHematopoietic pre-B cell leukemia transcription factor (PBX)-interacting protein (HPIP) was shown to play a role in cancer development and progression. However, the role of HPIP in colorectal cancer (CRC) is unknown. Here, we report that HPIP is overexpressed in most of CRC patients and predicts poor clinical outcome in CRC. HPIP promotes CRC cell proliferation via activation of G1/S and G2/M checkpoint transitions, concomitant with a marked increase of the positive cell cycle regulators, including cyclin D1, cyclin A and cyclin B1. HPIP inhibits CRC cell apoptosis accompanied by the decreased levels of BAX and PIG3, the inducers of apoptosis and the increased level of the apoptosis inhibitor BCL2. HPIP blocks caspase-3-mediated cleavage of PARP, an important apoptosis marker. HPIP promotes CRC cell migration and invasion and regulates epithelial-mesenchymal transition (EMT), which plays a critical role in cancer cell migration and invasion. Activation of MAPK/ERK1/2 and PI3k/AKT pathways is required for HPIP modulation of CRC cell proliferation, migration and EMT. Moreover, HPIP knockdown suppresses colorectal tumor growth in nude mice. These data highlight the important role of HPIP in CRC cell proliferation and progression and suggest that HPIP may be a useful target for CRC therapy.
Parametric excitation of multiple resonant radiations from localized wavepackets
Authors: Conforti Matteo , Trillo Stefano , Mussot Arnaud , Kudlinski Alexandre 
Published: March 2015

AbstractFundamental physical phenomena such as laser-induced ionization, driven quantum tunneling, Faraday waves, Bogoliubov quasiparticle excitations and the control of new states of matter rely on time-periodic driving of the system. A remarkable property of such driving is that it can induce the localized (bound) states to resonantly couple to the continuum. Therefore experiments that allow for enlightening and controlling the mechanisms underlying such coupling are of paramount importance. We implement such an experiment in a special optical fiber characterized by a dispersion oscillating along the propagation coordinate, which mimics “time”. The quasi-momentum associated with such periodic perturbation is responsible for the efficient coupling of energy from the localized wave-packets (solitons in anomalous dispersion and shock fronts in normal dispersion) sustained by the fiber nonlinearity, into free-running linear dispersive waves (continuum) at multiple resonant frequencies. Remarkably, the observed resonances can be explained by means of a unified approach, regardless of the fact that the localized state is a soliton-like pulse or a shock front.
Abnormal pairing of X and Y sex chromosomes during meiosis I in interspecific hybrids of Phodopus campbelli and P. sungorus
Authors: Ishishita Satoshi , Tsuboi Kazuma , Ohishi Namiko , Tsuchiya Kimiyuki , Matsuda Yoichi 
Published: March 2015

AbstractHybrid sterility plays an important role in the maintenance of species identity and promotion of speciation. Male interspecific hybrids from crosses between Campbell's dwarf hamster (Phodopus campbelli) and the Djungarian hamster (P. sungorus) exhibit sterility with abnormal spermatogenesis. However, the meiotic phenotype of these hybrids has not been well described. In the present work, we observed the accumulation of spermatocytes and apoptosis of spermatocyte-like cells in the testes of hybrids between P. campbelli females and P. sungorus males. In hybrid spermatocytes, a high frequency of asynapsis of X and Y chromosomes during the pachytene-like stage and dissociation of these chromosomes during metaphase I (MI) was observed. No autosomal univalency was observed during pachytene-like and MI stages in the hybrids; however, a low frequency of synapsis between autosomes and X or Y chromosomes, interlocking and partial synapsis between autosomal pairs and γ-H2AFX staining in autosomal chromatin was observed during the pachytene-like stage. Degenerated MI-like nuclei were frequently observed in the hybrids. Most of the spermatozoa in hybrid epididymides exhibited head malformation. These results indicate that the pairing of X and Y chromosomes is more adversely affected than that of autosomes in Phodopus hybrids.
Molecular-Orientation-Induced Rapid Roughening and Morphology Transition in Organic Semiconductor Thin-Film Growth
Authors: Yang Junliang , Yim Sanggyu , Jones Tim S. 
Published: March 2015

AbstractWe study the roughening process and morphology transition of organic semiconductor thin film induced by molecular orientation in the model of molecular semiconductor copper hexadecafluorophthalocyanine (F16CuPc) using both experiment and simulation. The growth behaviour of F16CuPc thin film with the thickness, D, on SiO2 substrate takes on two processes divided by a critical thickness: (1) D ≤ 40 nm, F16CuPc thin films are composed of uniform caterpillar-like crystals. The kinetic roughening is confirmed during this growth, which is successfully analyzed by Kardar-Parisi-Zhang (KPZ) model with scaling exponents α = 0.71 ± 0.12, β = 0.36 ± 0.03 and 1/z = 0.39 ± 0.12; (2) D > 40 nm, nanobelt crystals are formed gradually on the caterpillar-like crystal surface and the film growth shows anomalous growth behaviour. These new growth behaviours with two processes result from the gradual change of molecular orientation and the formation of grain boundaries, which conversely induce new molecular orientation, rapid roughening process and the formation of nanobelt crystals.
Glucocorticoid receptors in the locus coeruleus mediate sleep disorders caused by repeated corticosterone treatment
Authors: Wang Zi-Jun , Zhang Xue-Qiong , Cui Xiang-Yu , Cui Su-Ying , Yu Bin , Sheng Zhao-Fu , Li Sheng-Jie , Cao Qing , Huang Yuan-Li , Xu Ya-Ping , Zhang Yong-He 
Published: March 2015

AbstractStress induced constant increase of cortisol level may lead to sleep disorder, but the mechanism remains unclear. Here we described a novel model to investigate stress mimicked sleep disorders induced by repetitive administration of corticosterone (CORT). After 7 days treatment of CORT, rats showed significant sleep disturbance, meanwhile, the glucocorticoid receptor (GR) level was notably lowered in locus coeruleus (LC). We further discovered the activation of noradrenergic neuron in LC, the suppression of GABAergic neuron in ventrolateral preoptic area (VLPO), the remarkable elevation of norepinephrine in LC, VLPO and hypothalamus, as well as increase of tyrosine hydroxylase in LC and decrease of glutamic acid decarboxylase in VLPO after CORT treatment. Microinjection of GR antagonist RU486 into LC reversed the CORT-induced sleep changes. These results suggest that GR in LC may play a key role in stress-related sleep disorders and support the hypothesis that repeated CORT treatment may decrease GR levels and induce the activation of noradrenergic neurons in LC, consequently inhibit GABAergic neurons in VLPO and result in sleep disorders. Our findings provide novel insights into the effect of stress-inducing agent CORT on sleep and GRs' role in sleep regulation.
Structure and function of a Clostridium difficile sortase enzyme
Authors: Chambers Christopher J. , Roberts April K. , Shone Clifford C. , Acharya K. Ravi 
Published: March 2015

AbstractSortase enzymes are responsible for covalent anchoring of specific proteins to the peptidoglycan of the cell wall of gram-positive bacteria. In some gram-positive bacteria (e.g. Staphylococcus aureus), sortases have been found to be essential for pathogenesis and their inhibitors are under development as potential novel therapeutics. Here we provide the first report on the structural characterisation of the C. difficile sortase. An active site mutant was crystallised and its structure determined to 2.55 Å by X-ray diffraction to provide structural insight into its catalytic mechanism. In order to elucidate the role of the sortase in the cell wall biogenesis, a C. difficile sortase knockout strain was constructed by intron mutagenesis. Characterisation of this mutant led to the discovery that the putative adhesin CD0386 is anchored to the peptidoglycan of C. difficile by the sortase SrtB and that an SPKTG peptide motif is involved in the transpeptidation reaction with the C. difficile peptidoglycan. In an animal model for C. difficile infection, the SrtB mutant caused disease at a similar rate of onset as the wild type strain. In conclusion, our detailed study shows that the SrtB enzyme from C. difficile does not play an essential role in pathogenesis.
Sex differences in mania phenotype and ethanol consumption in the lateral hypothalamic kindled rat model
Authors: Abulseoud O A , Gawad N A , Mohamed K , Vadnie C , Camsari U M , Karpyak V , Frye M A , Choi D-S 
Published: March 2015

AbstractSex differences have been observed in mania phenotypes in humans. However the mechanisms underlying this difference are poorly understood. Activating the lateral hypothalamus is implicated in manic-like behaviors in rodents. Using newly established lateral hypothalamus kindled (LHK) rat mania model, we investigated sex differences of manic-like behaviors and its correlation with voluntary ethanol intake. We stimulated the lateral hypothalamus bilaterally in the male and female Wistar rats over five consecutive days. We recorded and quantified kindling-induced behaviors for each individual animal. We also assessed ethanol consumption using a two-bottle choice ethanol drinking as well as circadian locomotor activity counts daily throughout the experiment. We found notable sex differences in several aspects of manic-like behaviors during kindling. Males exhibited a significantly increased locomotor activity during the light phase, and reduced rest interval. On the other hand, females displayed significantly higher ethanol consumption and more frequent rearing behavior. However, no sex differences were present in the duration of sexual, feeding or grooming behaviors or in dark-phase activity counts. The excessive alcohol intake in LHK female rats is reminiscent of clinically reported sex differences in bipolar patients while the other phenotypic sex differences such as rearing and locomotor activity are less clearly described in clinical studies. Overall, our results lend further evidence for the validity of the LHK rat as a useful model to study brain region-specific molecular changes during mania and its correlation with alcohol use disorders.
Spatial distribution and temporal evolution of DRONPA-fused SNAP25 clusters in adrenal chromaffin cells
Authors: Antoku Yasuko , Dedecker Peter , Pinheiro Paulo S. , Vosch Tom , Sørensen Jakob Balslev 
Published: March 2015

Abstract
Sub-diffraction imaging of plasma membrane localized proteins, such as the SNARE (SolubleNSFAttachment Protein Receptor) proteins involved in exocytosis, in fixed cells have resulted in images with high spatial resolution, at the expense of dynamical information. Here, we have imaged localized fluorescence bursts of DRONPA-fused SNAP-25 molecules in live chromaffin cells by Total Internal Reflection Fluorescence (TIRF) imaging. We find that this method allows tracking protein cluster dynamics over relatively long times (∼20 min.), partly due to the diffusion into the TIRF field of fresh molecules, making possible the simultaneous identification of cluster size, location and temporal evolution. The results indicate that the DRONPA-fused SNAP-25 clusters display rich dynamics, going from staying constant to disappearing and reappearing in specific cluster domains within minutes.
T-cell receptor α enhancer is inactivated in αβ T lymphocytes
Authors: del Blanco Beatriz , Angulo Úrsula , Krangel Michael S. , Hernández-Munain Cristina 
Published: March 2015

SignificanceTheTcraenhancer (Eα) is essential during thymocyte development forTcragermline transcription, Vα-to-Jα rearrangement, and the generation of αβ T-lymphocytes. It has been assumed that Eα displays constitutive activity to drive the expression of rearrangedTcragenes in mature T cells. We show that Eα is dramatically inhibited in peripheral T-lymphocytes and is not reactivated in the context of antigen-mediated stimulation or T helper differentiation. We conclude that the major function of Eα is to coordinate the formation of a chromatin hub that drives germline transcription and primaryTcrarearrangements in DP thymocytes. Our results also imply the existence of an Eα-independent molecular mechanism that directs transcription of the rearrangedTcralocus in αβ T cells.
Structural mechanisms of DNA binding and unwinding in bacterial RecQ helicases
Authors: Manthei Kelly A. , Hill Morgan C. , Burke Jordan E. , Butcher Samuel E. , Keck James L. 
Published: March 2015

Significance
RecQ DNA helicases catalyze critical genome maintenance reactions in nearly all organisms. This study describes the crystal structure of a bacterial RecQ helicase bound in a productive complex with DNA. Together with biochemical experiments, the structure reveals a conserved coupling mechanism that links DNA binding to ATP hydrolysis in RecQ enzymes. These findings also help explain how structural dynamics could facilitate RecQ’s noted ability to process diverse DNA substrates. A model explaining the physical basis for RecQ substrate binding and unwinding is proposed.
Phosphorylation of ORF1p is required for L1 retrotransposition
Authors: Cook Pamela R. , Jones Charles E. , Furano Anthony V. 
Published: March 2015

Significance
All organisms contain transposable DNA elements (TEs) that can be seriously deleterious. The dominant TE in mammals, the L1 (LINE-1) retrotransposon, has generated approximately 40% of the genome. L1 encodes two proteins, ORF1p and ORF2p, that are required for L1 retrotransposition. We show here that phosphorylation of ORF1p is required for this process. These results significantly advance our understanding of retrotransposition and indicate that L1 activity is integrated with, and thus potentially can perturb, host cellular signaling pathways. Thus, the effects of L1 may extend well beyond those of genome alteration as is currently thought.
Human RECQ1 helicase-driven DNA unwinding, annealing, and branch migration: Insights from DNA complex structures
Authors: Pike Ashley C. W. , Gomathinayagam Shivasankari , Swuec Paolo , Berti Matteo , Zhang Ying , Schnecke Christina , Marino Francesca , von Delft Frank , Renault Ludovic , Costa Alessandro , Gileadi Opher , Vindigni Alessandro 
Published: March 2015

Significance
RecQ DNA helicases are critical enzymes for the maintenance of genome integrity. Here, we determined the first DNA complex structures, to our knowledge, of the human RECQ1 helicase. These structures provide new insight into the RecQ helicase mechanism of DNA tracking, strand separation, strand annealing, and Holliday junction (HJ) branch migration. We identified a surface region in the winged-helix domain of RECQ1 that is important for both dsDNA recognition and HJ resolution, and we used a combination of biochemical, analytical ultracentrifugation, and EM experiments to begin elucidating the molecular basis of the distinct HJ resolution activities of human RecQ helicases.
Cross-talk between PKA-Cβ and p65 mediates synergistic induction of PDE4B by roflumilast and NTHi
Authors: Susuki-Miyata Seiko , Miyata Masanori , Lee Byung-Cheol , Xu Haidong , Kai Hirofumi , Yan Chen , Li Jian-Dong 
Published: March 2015

SignificanceChronic obstructive pulmonary disease (COPD) is the fourth-leading cause of death worldwide. Roflumilast has been approved for COPD. However, its efficacy has been hampered by the development of tolerance, and the underlying mechanism remains unknown but may be attributed to phosphodiesterase (PDE) 4B up-regulation. Here we found that PDE4B2 is synergistically up-regulated by inflammatory stimuli (e.g. bacteria) and cAMP-elevating agents (e.g. roflumilast) via cross-talk between protein kinase A catalytic subunit β and NF-κB p65 in a cAMP-dependent manner. Up-regulated PDE4B2 contributes to the induction of certain key chemokines in both enzymatic activity-dependent and activity-independent manners. Our findings may explain, at least in part, the development of tolerance and help develop new therapeutics to improve efficacy of roflumilast.
A viral regulator of glycoprotein complexes contributes to human cytomegalovirus cell tropism
Authors: Li Gang , Nguyen Christopher C. , Ryckman Brent J. , Britt William J. , Kamil Jeremy P. 
Published: March 2015

Significance
The entry of a virus into a cell is a fundamental step during infection. In certain herpesviruses, including Epstein–Barr virus, human herpesvirus 6, and human cytomegalovirus (HCMV), a viral glycoprotein complex, gH/gL, plays key roles in entry and is found in two different forms on virions. The relative abundance of the two different types of gH/gL complexes is influenced by the type of cell from which the virus is produced and influences the tropism of the virus for different cell types. We have identified a viral glycoprotein, UL148, that influences the cell tropism of HCMV virions by regulating the relative amounts of these two gH/gL complexes. Our findings have implications for understanding how herpesviruses navigate through host tissues.
Leader emergence through interpersonal neural synchronization
Authors: Jiang Jing , Chen Chuansheng , Dai Bohan , Shi Guang , Ding Guosheng , Liu Li , Lu Chunming 
Published: March 2015

SignificanceGreat leaders are often great communicators. However, little is known about the neural basis of leader–follower communication. Only recently have neuroscientists been able to examine interpersonal neural synchronization (INS) between leaders and followers during social interactions. Here, we show that INS is significantly higher between leaders and followers than between followers and followers, suggesting that leaders emerge by synchronizing their brain activity with that of the followers. Moreover, the quality rather than frequency of the leaders’ communications makes a significant contribution to the increase of INS. This result supports the “quality of communication” hypothesis in leader emergence. Finally, our results show that leadership can be predicted shortly after the onset of a task based on INS as well as communication behaviors.
Non-native plants add to the British flora without negative consequences for native diversity
Authors: Thomas Chris D. , Palmer G. 
Published: March 2015

Significance
Non-native plants dominate global lists of invasive (harmful) species, yet plants introduced to Britain are both less widespread than native species and not increasing any more than native plants, and changes to native and non-native plant diversity are positively associated. The hypothesis that competitive exclusion will eventually enable introduced plants to drive native species extinct receives no support, according to analysis of extensive British data. A more parsimonious explanation is that both native and introduced plants are responding predominantly to other drivers of environmental change. The negative effects of non-native plants on British biodiversity have been exaggerated, and may also have been exaggerated in other parts of the world.
Area burned in the western United States is unaffected by recent mountain pine beetle outbreaks
Authors: Hart Sarah J. , Schoennagel Tania , Veblen Thomas T. , Chapman Teresa B. 
Published: March 2015

SignificanceAcross western North America, abundant susceptible pine hosts and a suitable climate during the early 21st century have promoted widespread mountain pine beetle (MPB) outbreaks, leading to concern that dead fuels may increase wildfire risk. The assumption that outbreaks raise fire risk is driving far-reaching policy decisions involving expenditures of hundreds of millions of dollars. Contrary to the expectation that an MPB outbreak increases fire risk, spatial overlay analysis shows no effect of outbreaks on subsequent area burned during years of extreme burning across the West. These results refute the assumption that increased bark beetle activity has increased area burned; therefore, policy discussions should focus on societal adaptation to the effects of the underlying drivers: warmer temperatures and increased drought.
cGAS-mediated stabilization of IFI16 promotes innate signaling during herpes simplex virus infection
Authors: Orzalli Megan H. , Broekema Nicole M. , Diner Benjamin A. , Hancks Dustin C. , Elde Nels C. , Cristea Ileana M. , Knipe David M. 
Published: March 2015

Significance
Interferon γ-inducible protein 16 (IFI16) and cGMP-AMP synthase (cGAS) have both been proposed to directly detect herpesviral DNA in herpes simplex virus (HSV)-infected cells and initiate interferon regulatory factor-3 signaling, but it has been unclear how two DNA sensors could both be required. Both are required in human fibroblasts for detection of HSV and transfected DNAs. We found evidence that IFI16 plays a direct role in HSV DNA sensing, whereas cGAS produces low amounts of cGAMP and promotes the stability of IFI16. Our results demonstrate a new function for cGAS in the maintenance of normal levels of IFI16 and provide an explanation for the multiple proposed DNA sensors.