bluuebunny/crossref_metadata_2025 huggingface dataset:
BCAS2 is involved in alternative mRNA splicing in spermatogonia and the transition to meiosis
Authors: Liu Wenbo , Wang Fengchao , Xu Qianhua , Shi Junchao , Zhang Xiaoxin , Lu Xukun , Zhao Zhen-Ao , Gao Zheng , Ma Huaixiao , Duan Enkui , Gao Fei , Gao Shaorong , Yi Zhaohong , Li Lei
Published: January 2017

Breast cancer amplified sequence 2 (BCAS2) is involved in multiple biological processes, including pre-mRNA splicing. However, the physiological roles of BCAS2 are still largely unclear. Here we report that BCAS2 is specifically enriched in spermatogonia of mouse testes. Conditional disruption of Bcas2 in male germ cells impairs spermatogenesis and leads to male mouse infertility. Although the spermatogonia appear grossly normal, spermatocytes in meiosis prophase I and meiosis events (recombination and synapsis) are rarely observed in the BCAS2-depleted testis. In BCAS2 null testis, 245 genes are altered in alternative splicing forms; at least three spermatogenesis-related genes (Dazl, Ehmt2 and Hmga1) can be verified. In addition, disruption of Bcas2 results in a significant decrease of the full-length form and an increase of the short form (lacking exon 8) of DAZL protein. Altogether, our results suggest that BCAS2 regulates alternative splicing in spermatogonia and the transition to meiosis initiation, and male fertility.
Highly tensile-strained Ge/InAlAs nanocomposites
Authors: Jung Daehwan , Faucher Joseph , Mukherjee Samik , Akey Austin , Ironside Daniel J. , Cabral Matthew , Sang Xiahan , Lebeau James , Bank Seth R. , Buonassisi Tonio , Moutanabbir Oussama , Lee Minjoo Larry
Published: January 2017

Self-assembled nanocomposites have been extensively investigated due to the novel properties that can emerge when multiple material phases are combined. Growth of epitaxial nanocomposites using lattice-mismatched constituents also enables strain-engineering, which can be used to further enhance material properties. Here, we report self-assembled growth of highly tensile-strained Ge/In0.52Al0.48As (InAlAs) nanocomposites by using spontaneous phase separation. Transmission electron microscopy shows a high density of single-crystalline germanium nanostructures coherently embedded in InAlAs without extended defects, and Raman spectroscopy reveals a 3.8% biaxial tensile strain in the germanium nanostructures. We also show that the strain in the germanium nanostructures can be tuned to 5.3% by altering the lattice constant of the matrix material, illustrating the versatility of epitaxial nanocomposites for strain engineering. Photoluminescence and electroluminescence results are then discussed to illustrate the potential for realizing devices based on this nanocomposite material.
A tachykinin-like neuroendocrine signalling axis couples central serotonin action and nutrient sensing with peripheral lipid metabolism
Authors: Palamiuc Lavinia , Noble Tallie , Witham Emily , Ratanpal Harkaranveer , Vaughan Megan , Srinivasan Supriya
Published: January 2017

Serotonin, a central neuromodulator with ancient ties to feeding and metabolism, is a major driver of body fat loss. However, mechanisms by which central serotonin action leads to fat loss remain unknown. Here, we report that the FLP-7 neuropeptide and its cognate receptor, NPR-22, function as the ligand-receptor pair that defines the neuroendocrine axis of serotonergic body fat loss in Caenorhabditis elegans. FLP-7 is secreted as a neuroendocrine peptide in proportion to fluctuations in neural serotonin circuit functions, and its release is regulated from secretory neurons via the nutrient sensor AMPK. FLP-7 acts via the NPR-22/Tachykinin2 receptor in the intestine and drives fat loss via the adipocyte triglyceride lipase ATGL-1. Importantly, this ligand-receptor pair does not alter other serotonin-dependent behaviours including food intake. For global modulators such as serotonin, the use of distinct neuroendocrine peptides for each output may be one means to achieve phenotypic selectivity.
Unravelling raked linear dunes to explain the coexistence of bedforms in complex dunefields
Authors: Lü Ping , Narteau Clément , Dong Zhibao , Rozier Olivier , Courrech du Pont Sylvain
Published: January 2017

Raked linear dunes keep a constant orientation for considerable distances with a marked asymmetry between a periodic pattern of semi-crescentic structures on one side and a continuous slope on the other. Here we show that this shape is associated with a steady-state dune type arising from the coexistence of two dune growth mechanisms. Primary ridges elongate in the direction of the resultant sand flux. Semi-crescentic structures result from the development of superimposed dunes growing perpendicularly to the maximum gross bedform-normal transport. In the particular case of raked linear dunes, these two mechanisms produces primary and secondary ridges with similar height but with different orientations, which are oblique to each other. The raked pattern develops preferentially on the leeward side of the primary ridges according to the direction of propagation of the superimposed bedforms. As shown by numerical modelling, raked linear dunes occur where both these oblique orientations and dynamics are met.
Rapid trait evolution drives increased speed and variance in experimental range expansions
Authors: Weiss-Lehman Christopher , Hufbauer Ruth A , Melbourne Brett A
Published: January 2017

Range expansions are central to two ecological issues reshaping patterns of global biodiversity: biological invasions and climate change. Traditional theory considers range expansion as the outcome of the demographic processes of birth, death and dispersal, while ignoring the evolutionary implications of such processes. Recent research suggests evolution could also play a critical role in determining expansion speed but controlled experiments are lacking. Here we use flour beetles (Tribolium castaneum) to show experimentally that mean expansion speed and stochastic variation in speed are both increased by rapid evolution of traits at the expansion edge. We find that higher dispersal ability and lower intrinsic growth rates evolve at the expansion edge compared with spatially nonevolving controls. Furthermore, evolution of these traits is variable, leading to enhanced variance in speed among replicate population expansions. Our results demonstrate that evolutionary processes must be considered alongside demographic ones to better understand and predict range expansions.
A generalized model for time-resolved luminescence of localized carriers and applications: Dispersive thermodynamics of localized carriers
Authors: Su Zhicheng , Xu Shijie
Published: January 2017

For excited carriers or electron-hole coupling pairs (excitons) in disordered crystals, they may localize and broadly distribute within energy space first, and then experience radiative recombination and thermal transfer (i.e., non-radiative recombination via multi-phonon process) processes till they eventually return to their ground states. It has been known for a very long time that the time dynamics of these elementary excitations is energy dependent or dispersive. However, theoretical treatments to the problem are notoriously difficult. Here, we develop an analytical generalized model for temperature dependent time-resolved luminescence, which is capable of giving a quantitative description of dispersive carrier dynamics in a wide temperature range. The two effective luminescence and nonradiative recombination lifetimes of localized elementary excitations were mathematically derived as
$${{\boldsymbol{\tau }}}_{{\boldsymbol{L}}}{\boldsymbol{=}}\frac{{{\boldsymbol{\tau }}}_{{\boldsymbol{r}}}}{{\bf{1}}{\boldsymbol{+}}\tfrac{{{\boldsymbol{\tau }}}_{{\boldsymbol{r}}}}{{{\boldsymbol{\tau }}}_{{\boldsymbol{t}}{\boldsymbol{r}}}}({\bf{1}}{\boldsymbol{-}}{{\boldsymbol{\gamma }}}_{{\boldsymbol{c}}}){{\boldsymbol{e}}}^{({\boldsymbol{E}}{\boldsymbol{-}}{{\boldsymbol{E}}}_{{\boldsymbol{a}}}){\boldsymbol{/}}{{\boldsymbol{k}}}_{{\boldsymbol{B}}}{\boldsymbol{T}}}}$$

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$${{\boldsymbol{\tau }}}_{{\boldsymbol{n}}{\boldsymbol{r}}}{\boldsymbol{=}}\frac{{{\boldsymbol{\tau }}}_{{\boldsymbol{t}}{\boldsymbol{r}}}}{({\bf{1}}{\boldsymbol{-}}{{\boldsymbol{\gamma }}}_{{\boldsymbol{c}}})}{{\boldsymbol{e}}}^{{\boldsymbol{-}}({\boldsymbol{E}}{\boldsymbol{-}}{{\boldsymbol{E}}}_{{\boldsymbol{a}}}){\boldsymbol{/}}{{\boldsymbol{k}}}_{{\boldsymbol{B}}}{\boldsymbol{T}}}$$

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, respectively. The model is successfully applied to quantitatively interpret the time-resolved luminescence data of several material systems, showing its universality and accuracy.
Analysis of carotenogenic genes promoters and WRKY transcription factors in response to salt stress in Dunaliella bardawil
Authors: Liang Ming-Hua , Jiang Jian-Guo
Published: January 2017

The unicellular alga Dunaliella bardawil is a highly salt-tolerant organism, capable of accumulating glycerol, glycine betaine and β-carotene under salt stress, and has been considered as an excellent model organism to investigate the molecular mechanisms of salt stress responses. In this study, several carotenogenic genes (DbCRTISO, DbZISO, DbLycE and DbChyB), DbBADH genes involved in glycine betaine synthesis and genes encoding probable WRKY transcription factors from D. bardawil were isolated, and promoters of DbCRTISO and DbChyB were cloned. The promoters of DbPSY, DbLycB, DbGGPS, DbCRTISO and DbChyB contained the salt-regulated element (SRE), GT1GMSCAM4, while the DbGGPS promoter has another SRE, DRECRTCOREAT. All promoters of the carotenogenic genes had light-regulated elements and W-box cis-acting elements. Most WRKY transcription factors can bind to the W-box, and play roles in abiotic stress. qRT-PCR analysis showed that salt stress up-regulated both carotenogenic genes and WRKY transcription factors. In contrast, the transcription levels of DbBADH showed minor changes. In D. bardawil, it appears that carotenoid over-accumulation allows for the long-term adaptation to salt stress, while the rapid modulation of glycine betaine biosynthesis provides an initial response.
Astrocyte-derived tissue Transglutaminase affects fibronectin deposition, but not aggregation, during cuprizone-induced demyelination
Authors: Espitia Pinzon Nathaly , Sanz-Morello Berta , Brevé John J. P. , Bol John G. J. M. , Drukarch Benjamin , Bauer Jan , Baron Wia , van Dam Anne-Marie
Published: January 2017

Astrogliosis as seen in Multiple Sclerosis (MS) develops into astroglial scarring, which is beneficial because it seals off the site of central nervous system (CNS) damage. However, astroglial scarring also forms an obstacle that inhibits axon outgrowth and (re)myelination in brain lesions. This is possibly an important cause for incomplete remyelination in the CNS of early stage MS patients and for failure in remyelination when the disease progresses. In this study we address whether under demyelinating conditions in vivo, tissue Transglutaminase (TG2), a Ca2+ -dependent enzyme that catalyses posttranslational modification of proteins, contributes to extracellular matrix (ECM) deposition and/or aggregation. We used the cuprizone model for de- and remyelination. TG2 immunoreactivity and enzymatic activity time-dependently appeared in astrocytes and ECM, respectively, in the corpus callosum of cuprizone-treated mice. Enhanced presence of soluble monomeric and multimeric fibronectin was detected during demyelination, and fibronectin immunoreactivity was slightly decreased in cuprizone-treated TG2−/− mice. In vitro TG2 overexpression in astrocytes coincided with more, while knock-down of TG2 with less fibronectin production. TG2 contributes, at least partly, to fibronectin production, and may play a role in fibronectin deposition during cuprizone-induced demyelination. Our observations are of interest in understanding the functional implications of TG2 during astrogliosis.
Quantifying mating success of territorial males and sneakers in a bower-building cichlid fish
Authors: Magalhaes I. S. , Smith A. M. , Joyce D. A.
Published: January 2017

The strategies and traits males evolve to mate with females are incredible in their diversity. Theory on the evolution of secondary sexual characters suggests that evolving any costly trait or strategy will pay off and stabilise in the population if it is advantageous compared to the alternative less costly strategy, but quantifying the relative success of the two can be difficult. In Lake Malawi, Africa, there are >200 species of cichlid fish in which the males form leks and spend several weeks per year building sand-castle “bowers” several times their size. We tested the idea that a less costly “sneaking” strategy could be successful by quantifying the mating success of bower-holding versus non-bower-holding males. We PIT-tagged every fish in a semi-natural experimental set-up and placed tag-readers on the side of bowers to determine which fish held a bower. We then genotyped the eggs removed from females’ mouths to assign paternity of each egg. Broods were fathered by up to 3 different males. Although paternity was mostly assigned to males that held a bower, a small number of males who did not own a bower were more successful than some of those that did, indicating a role for an alternative strategy in these bower builders.
M2 macrophages or IL-33 treatment attenuate ongoing Mycobacterium tuberculosis infection
Authors: Piñeros A. R. , Campos L. W. , Fonseca D. M. , Bertolini T. B. , Gembre A. F. , Prado R. Q. , Alves-Filho J. C. , Ramos S. G. , Russo M. , Bonato V. L. D.
Published: January 2017

The protective effects of mycobacterial infections on lung allergy are well documented. However, the inverse relationship between tuberculosis and type 2 immunity is still elusive. Although type 1 immunity is essential to protection against Mycobacterium tuberculosis it might be also detrimental to the host due to the induction of extensive tissue damage. Here, we determined whether lung type 2 immunity induced by allergen sensitization and challenge could affect the outcome of M. tuberculosis infection. We used two different protocols in which sensitization and allergen challenge were performed before or after M. tuberculosis infection. We found an increased resistance to M. tuberculosis only when allergen exposure was given after, but not before infection. Infected mice exposed to allergen exhibited lower bacterial load and cellular infiltrates in the lungs. Enhanced resistance to infection after allergen challenge was associated with increased gene expression of alternatively activated macrophages (M2 macrophages) and IL-33 levels. Accordingly, either adoptive transfer of M2 macrophages or systemic IL-33 treatment was effective in attenuating M. tuberculosis infection. Notably, the enhanced resistance induced by allergen exposure was dependent on IL-33 receptor ST2. Our work indicates that IL-33 might be an alternative therapeutic treatment for severe tuberculosis.
Targeted delivery of an ADP-ribosylating bacterial toxin into cancer cells
Authors: Zahaf N.-I. , Lang A. E. , Kaiser L. , Fichter C. D. , Lassmann S. , McCluskey A. , Augspach A. , Aktories K. , Schmidt G.
Published: January 2017

The actin cytoskeleton is an attractive target for bacterial toxins. The ADP-ribosyltransferase TccC3 from the insect bacterial pathogenPhotorhabdus luminescencemodifies actin to force its aggregation. We intended to transport the catalytic part of this toxin preferentially into cancer cells using a toxin transporter (Protective antigen, PA) which was redirected to Epidermal Growth Factor Receptors (EGFR) or to human EGF receptors 2 (HER2), which are overexpressed in several cancer cells. Protective antigen of anthrax toxin forms a pore through which the two catalytic parts (lethal factor and edema factor) or other proteins can be transported into mammalian cells. Here, we used PA as a double mutant (N682A, D683A; mPA) which cannot bind to the two natural anthrax receptors. Each mutated monomer is fused either to EGF or to an affibody directed against the human EGF receptor 2 (HER2). We established a cellular model system composed of two cell lines representing HER2 overexpressing esophageal adenocarcinomas (EACs) and EGFR overexpressing esophageal squamous cell carcinomas (ESCCs). We studied the specificity and efficiency of the re-directed anthrax pore for transport of TccC3 toxin and establishedPhotorhabdus luminescenceTccC3 as a toxin suitable for the development of a targeted toxin selectively killing cancer cells.
Cornea organoids from human induced pluripotent stem cells
Authors: Foster James W. , Wahlin Karl , Adams Sheila M. , Birk David E. , Zack Donald J. , Chakravarti Shukti
Published: January 2017

The cornea is the transparent outermost surface of the eye, consisting of a stratified epithelium, a collagenous stroma and an innermost single-cell layered endothelium and providing 2/3 of the refractive power of the eye. Multiple diseases of the cornea arise from genetic defects where the ultimate phenotype can be influenced by cross talk between the cell types and the extracellular matrix. Cell culture modeling of diseases can benefit from cornea organoids that include multiple corneal cell types and extracellular matrices. Here we present human iPS cell-derived organoids through sequential rounds of differentiation programs. These organoids share features of the developing cornea, harboring three distinct cell types with expression of key epithelial, stromal and endothelial cell markers. Cornea organoid cultures provide a powerful 3D model system for investigating corneal developmental processes and their disruptions in diseased conditions.
Prognostic Role of the Pretreatment C-Reactive Protein/Albumin Ratio in Solid Cancers: A Meta-Analysis
Authors: Li Nan , Tian Guang-Wei , Wang Ying , Zhang Hui , Wang Zi-hui , Li Guang
Published: January 2017

The C-reactive protein/albumin ratio (CAR) has been shown to play a significant prognostic role in several cancers. We aimed to comprehensively explore the potential role of the CAR as a prognostic indicator in solid cancers. In this meta-analysis, we collected data from 10 studies that examined the association between serum CAR and overall survival in patients with cancer. This meta-analysis included 4592 tumor patients. The eligible studies were found through the PubMed and Web of Science databases updated on 6 Oct 2016. The pooled hazard ratio (2.01, 95% CI: 1.58–2.56, p < 0.001) indicated that high CAR yielded worse survival in different cancers. Subgroup analyses showed a significant association between CAR and prognosis, regardless of the cutoff value, cutoff value selection, treatment method, country, sample size, stage and cancer type. This meta-analysis suggests that CAR may be a potential prognostic marker in solid cancers. However, further large prospective studies should be conducted to explore the critical role of CAR in survival of cancer patients.
Neutrophil gelatinase-associated lipocalin (NGAL) fails as an early predictor of contrast induced nephropathy in chronic kidney disease (ANTI-CI-AKI study)
Authors: Ribitsch Werner , Schilcher Gernot , Quehenberger Franz , Pilz Stefan , Portugaller Rupert H. , Truschnig-Wilders Martini , Zweiker Robert , Brodmann Marianne , Stiegler Philipp , Rosenkranz Alexander R. , Pickering John W. , Horina Joerg H.
Published: January 2017

The aim of the study was to evaluate the diagnostic accuracy of urinary neutrophil gelatinase- associated lipocalin (uNGAL) in patients with chronic kidney disease (CKD) as an early biomarker for contrast induced acute kidney injury (CI-AKI) and to investigate whether patients with an uNGAL increase might benefit from an additional intravenous volume expansion with regard to CI-AKI-incidence. We performed a prospective randomized controlled trial in 617 CKD-patients undergoing intra-arterial angiography. Urinary NGAL was measured the day before and 4–6hrs after angiography. In the event of a significant rise of uNGAL patients were randomized either into Group A, who received intravenous saline post procedure or Group B, who did not receive post-procedural i.v. fluids. Ten patients (1.62%) exhibited a significant rise of uNGAL after angiography and were randomized of whom one developed a CI-AKI. In the entire cohort the incidence of CI-AKI was 9.4% (58 patients) resulting in a specificity of 98.4% (95% CI: 97.0–99.3%) and a sensitivity of 1.72% (95% CI: 0.044–9.2%) of uNGAL for the diagnosis of CI-AKI. In this study uNGAL failed to predict CI-AKI and was an inadequate triage tool to guide an early intervention strategy to prevent CI-AKI. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01292317.
Highly Flexible and Transparent Ag Nanowire Electrode Encapsulated with Ultra-Thin Al2O3: Thermal, Ambient, and Mechanical Stabilities
Authors: Hwang Byungil , An Youngseo , Lee Hyangsook , Lee Eunha , Becker Stefan , Kim Yong-Hoon , Kim Hyoungsub
Published: January 2017

There is an increasing demand in the flexible electronics industry for highly robust flexible/transparent conductors that can withstand high temperatures and corrosive environments. In this work, outstanding thermal and ambient stability is demonstrated for a highly transparent Ag nanowire electrode with a low electrical resistivity, by encapsulating it with an ultra-thin Al2O3 film (around 5.3 nm) via low-temperature (100 °C) atomic layer deposition. The Al2O3-encapsulated Ag nanowire (Al2O3/Ag) electrodes are stable even after annealing at 380 °C for 100 min and maintain their electrical and optical properties. The Al2O3 encapsulation layer also effectively blocks the permeation of H2O molecules and thereby enhances the ambient stability to greater than 1,080 h in an atmosphere with a relative humidity of 85% at 85 °C. Results from the cyclic bending test of up to 500,000 cycles (under an effective strain of 2.5%) confirm that the Al2O3/Ag nanowire electrode has a superior mechanical reliability to that of the conventional indium tin oxide film electrode. Moreover, the Al2O3 encapsulation significantly improves the mechanical durability of the Ag nanowire electrode, as confirmed by performing wiping tests using isopropyl alcohol.
Discovering novel phenotypes with automatically inferred dynamic models: a partial melanocyte conversion in Xenopus
Authors: Lobo Daniel , Lobikin Maria , Levin Michael
Published: January 2017

Progress in regenerative medicine requires reverse-engineering cellular control networks to infer perturbations with desired systems-level outcomes. Such dynamic models allow phenotypic predictions for novel perturbations to be rapidly assessed in silico. Here, we analyzed a Xenopus model of conversion of melanocytes to a metastatic-like phenotype only previously observed in an all-or-none manner. Prior in vivo genetic and pharmacological experiments showed that individual animals either fully convert or remain normal, at some characteristic frequency after a given perturbation. We developed a Machine Learning method which inferred a model explaining this complex, stochastic all-or-none dataset. We then used this model to ask how a new phenotype could be generated: animals in which only some of the melanocytes converted. Systematically performing in silico perturbations, the model predicted that a combination of altanserin (5HTR2 inhibitor), reserpine (VMAT inhibitor), and VP16-XlCreb1 (constitutively active CREB) would break the all-or-none concordance. Remarkably, applying the predicted combination of three reagents in vivo revealed precisely the expected novel outcome, resulting in partial conversion of melanocytes within individuals. This work demonstrates the capability of automated analysis of dynamic models of signaling networks to discover novel phenotypes and predictively identify specific manipulations that can reach them.
Multilevel interaction of the DnaK/DnaJ(HSP70/HSP40) stress-responsive chaperone machine with the central metabolism
Authors: Anglès Fréderic , Castanié-Cornet Marie-Pierre , Slama Nawel , Dinclaux Mickael , Cirinesi Anne-Marie , Portais Jean-Charles , Létisse Fabien , Genevaux Pierre
Published: January 2017

Networks of molecular chaperones maintain cellular protein homeostasis by acting at nearly every step in the biogenesis of proteins and protein complexes. Herein, we demonstrate that the major chaperone DnaK/HSP70 of the model bacterium Escherichia coli is critical for the proper functioning of the central metabolism and for the cellular response to carbon nutrition changes, either directly or indirectly via the control of the heat-shock response. We identified carbon sources whose utilization was positively or negatively affected by DnaK and isolated several central metabolism genes (among other genes identified in this work) that compensate for the lack of DnaK and/or DnaK/Trigger Factor chaperone functions in vivo. Using carbon sources with specific entry points coupled to NMR analyses of real-time carbon assimilation, metabolic coproducts production and flux rearrangements, we demonstrate that DnaK significantly impacts the hierarchical order of carbon sources utilization, the excretion of main coproducts and the distribution of metabolic fluxes, thus revealing a multilevel interaction of DnaK with the central metabolism.
How white and black bodies are perceived depends on what emotion is expressed
Authors: Watson Rebecca , de Gelder Beatrice
Published: January 2017

Body language is a powerful indicator of others’ emotions in social interactions, with positive signals triggering approach and negative ones retreat and defensiveness. Intergroup and interracial factors can influence these interactions, sometimes leading to aggressive or even violent behaviour. Despite its obvious social relevance however, the interaction between body expression and race remains unexplored, with explanations of the impact of race being almost exclusively based on the role of race in face recognition. In the current fMRI study we scanned white European participants while they viewed affective (angry and happy) body postures of both same race (white) and other race (black) individuals. To assess the difference between implicit and explicit recognition participants performed either an explicit emotion categorisation task, or an irrelevant shape judgement task. Brain activity was modulated by race in a number of brain regions across both tasks. Race-related activity appeared to be task- as well as emotion- specific. Overall, the other-race effects appeared to be driven by positive emotions, while same-race effects were observed for negative emotions. A race specific effect was also observed in right amygdala reflecting increased activation for explicit recognition of angry white body expressions. Overall, these results provide the first clear evidence that race influences affective body perception.
Antimicrobial activity of ProRoot MTA in contact with blood
Authors: Farrugia C. , Baca P. , Camilleri J. , Arias Moliz M. T.
Published: January 2017

Dental materials based on Portland cement, which is used in the construction industry have gained popularity for clinical use due to their hydraulic properties, the interaction with tooth tissue and their antimicrobial properties. The antimicrobial properties are optimal in vitro. However in clinical use contact with blood may affect the antimicrobial properties. This study aims to assess whether antimicrobial properties of the Portland cement-based dental cements such as mineral trioxide aggregate (MTA) are also affected by contact with blood present in clinical situations. ProRoot MTA, a Portland cement-based dental cement was characterized following contact with water, or heparinized blood after 1 day and 7 days aging. The antimicrobial activity under the mentioned conditions was assessed using 3 antimicrobial tests: agar diffusion test, direct contact test and intratubular infection test. MTA in contact with blood was severely discoloured, exhibited an additional phosphorus peak in elemental analysis, no calcium hydroxide peaks and no areas of bacterial inhibition growth in the agar diffusion test were demonstrated. ProRoot MTA showed limited antimicrobial activity, in both the direct contact test and intratubular infection test. When aged in water ProRoot MTA showed higher antimicrobial activity than when aged in blood. Antimicrobial activity reduced significantly after 7 days. Further assessment is required to investigate behaviour in clinical situations.
Membrane-mediated action of the endocannabinoid anandamide on membrane proteins: implications for understanding the receptor-independent mechanism
Authors: Medeiros Djalma , Silva-Gonçalves Laíz da Costa , da Silva Annielle Mendes Brito , dos Santos Cabrera Marcia Perez , Arcisio-Miranda Manoel
Published: January 2017

Endocannabinoids are amphiphilic molecules that play crucial neurophysiological functions acting as lipid messengers. Antagonists and knockdown of the classical CB1 and CB2 cannabinoid receptors do not completely abolish many endocannabinoid activities, supporting the idea of a mechanism independent of receptors whose mode of action remains unclear. Here we combine gramicidin A (gA) single channel recordings and membrane capacitance measurements to investigate the lipid bilayer-modifying activity of endocannabinoids. Single channel recordings show that the incorporation of endocannabinoids into lipid bilayers reduces the free energy necessary for gramicidin channels to transit from the monomeric to the dimeric conformation. Membrane capacitance demonstrates that the endocannabinoid anandamide has limited effects on the overall structure of the lipid bilayers. Our results associated with the theory of membrane elastic deformation reveal that the action of endocannabinoids on membrane proteins can involve local adjustments of the lipid/protein hydrophobic interface. The current findings shed new light on the receptor-independent mode of action of endocannabinoids on membrane proteins, with important implications towards their neurobiological function.
Augmented laminography, a correlative 3D imaging method for revealing the inner structure of compressed fossils
Authors: Zuber Marcus , Laaß Michael , Hamann Elias , Kretschmer Sophie , Hauschke Norbert , van de Kamp Thomas , Baumbach Tilo , Koenig Thomas
Published: January 2017

Non-destructive imaging techniques can be extremely useful tools for the investigation and the assessment of palaeontological objects, as mechanical preparation of rare and valuable fossils is precluded in most cases. However, palaeontologists are often faced with the problem of choosing a method among a wide range of available techniques. In this case study, we employ x-ray computed tomography (CT) and computed laminography (CL) to study the first fossil xiphosuran from the Muschelkalk (Middle Triassic) of the Netherlands. The fossil is embedded in micritic limestone, with the taxonomically important dorsal shield invisible, and only the outline of its ventral part traceable. We demonstrate the complementarity of CT and CL which offers an excellent option to visualize characteristic diagnostic features. We introduceaugmented laminographyto correlate complementary information of the two methods in Fourier space, allowing to combine their advantages and finally providing increased anatomical information about the fossil. This method of augmented laminography enabled us to identify the xiphosuran as a representative of the genusLimulitella.
Gd-EOB-DTPA-enhanced MR relaxometry for the detection and staging of liver fibrosis
Authors: Haimerl Michael , Utpatel Kirsten , Verloh Niklas , Zeman Florian , Fellner Claudia , Nickel Dominik , Teufel Andreas , Fichtner-Feigl Stefan , Evert Matthias , Stroszczynski Christian , Wiggermann Philipp
Published: January 2017

Gd-EOB-DTPA, a liver-specific contrast agent with T1-shortening effects, is routinely used in clinical routine for detection and characterization of focal liver lesions and has recently received increasing attention as a tool for the quantitative analyses of liver function. We report the relationship between the extent of Gd-EOB-DTPA- induced T1 relaxation and the degree of liver fibrosis, which was assessed according to the METAVIR score. For the T1 relaxometry, a transverse 3D VIBE sequence with inline T1 calculation was acquired prior to and 20 minutes after Gd-EOB-DTPA administration. The reduction rates of the T1 relaxation time (rrT1) between the pre- and postcontrast images were calculated, and the optimal cutoff values for the fibrosis stages were determined with receiver operating characteristic (ROC) curve analyses. The rrT1 decreased with the severity of liver fibrosis and regression analysis revealed a significant correlation of the rrT1 with the stage of liver fibrosis (r = −0.906, p < 0.001). ROC analysis revealed sensitivities ≥78% and specificities ≥94% for the differentiation of different fibrosis stages. Gd-EOB-DTPA–enhanced T1 relaxometry is a reliable tool for both the detection of initial hepatic fibrosis and the staging of hepatic fibrosis.
Efficient single-pixel multispectral imaging via non-mechanical spatio-spectral modulation
Authors: Li Ziwei , Suo Jinli , Hu Xuemei , Deng Chao , Fan Jingtao , Dai Qionghai
Published: January 2017

Combining spectral imaging with compressive sensing (CS) enables efficient data acquisition by fully utilizing the intrinsic redundancies in natural images. Current compressive multispectral imagers, which are mostly based on array sensors (e.g, CCD or CMOS), suffer from limited spectral range and relatively low photon efficiency. To address these issues, this paper reports a multispectral imaging scheme with a single-pixel detector. Inspired by the spatial resolution redundancy of current spatial light modulators (SLMs) relative to the target reconstruction, we design an all-optical spectral splitting device to spatially split the light emitted from the object into several counterparts with different spectrums. Separated spectral channels are spatially modulated simultaneously with individual codes by an SLM. This no-moving-part modulation ensures a stable and fast system, and the spatial multiplexing ensures an efficient acquisition. A proof-of-concept setup is built and validated for 8-channel multispectral imaging within 420~720 nm wavelength range on both macro and micro objects, showing a potential for efficient multispectral imager in macroscopic and biomedical applications.
Astaxanthin protects against early burn-wound progression in rats by attenuating oxidative stress-induced inflammation and mitochondria-related apoptosis
Authors: Fang Quan , Guo Songxue , Zhou Hanlei , Han Rui , Wu Pan , Han Chunmao
Published: January 2017

Burn-wound progression can occur in the initial or peri-burn area after a deep burn injury. The stasis zone has a higher risk of deterioration mediated by multiple factors but is also considered salvageable. Astaxanthin (ATX), which is extracted from some marine organisms, is a natural compound with a strong antioxidant effect that has been reported to attenuate organ injuries caused by traumatic injuries. Hence, we investigated the potential effects of ATX on preventing early burn-wound progression. A classic “comb” burn rat model was established in this study for histological and biological assessments, which revealed that ATX, particularly higher doses, alleviated histological deterioration in the stasis zone. Additionally, we observed dose-dependent improvements in oxidative stress and the release of inflammatory mediators after ATX treatment. Furthermore, ATX dose-dependently attenuated burn-induced apoptosis in the wound areas, and this effect was accompanied by increases in Akt and Bad phosphorylation and a downregulation of cytochrome C and caspase expression. In addition, the administration of Ly 294002 further verified the effect of ATX. In summary, we demonstrated that ATX protected against early burn-wound progression in a rat deep-burn model. This protection might be mediated by the attenuation of oxidative stress-induced inflammation and mitochondria-related apoptosis.
Ultrafast nonlinear optical properties of thin-solid DNA film and their application as a saturable absorber in femtosecond mode-locked fiber laser
Authors: Khazaeinezhad Reza , Hosseinzadeh Kassani Sahar , Paulson Bjorn , Jeong Hwanseong , Gwak Jiyoon , Rotermund Fabian , Yeom Dong-Il , Oh Kyunghwan
Published: January 2017

A new extraordinary application of deoxyribonucleic acid (DNA) thin-solid-film was experimentally explored in the field of ultrafast nonlinear photonics. Optical transmission was investigated in both linear and nonlinear regimes for two types of DNA thin-solid-films made from DNA in aqueous solution and DNA-cetyltrimethylammonium chloride (CTMA) in an organic solvent. Z-scan measurements revealed a high third-order nonlinearity with n2 exceeding 10−9 at a wavelength of 1570 nm, for a nonlinarity about five orders of magnitude larger than that of silica. We also demonstrated ultrafast saturable absorption (SA) with a modulation depth of 0.43%. DNA thin solid films were successfully deposited on a side-polished optical fiber, providing an efficient evanescent wave interaction. We built an organic-inorganic hybrid all-fiber ring laser using DNA film as an ultrafast SA and using Erbium-doped fiber as an efficient optical gain medium. Stable transform-limited femtosecond soliton pulses were generated with full width half maxima of 417 fs for DNA and 323 fs for DNA-CTMA thin-solid-film SAs. The average output power was 4.20 mW for DNA and 5.46 mW for DNA-CTMA. Detailed conditions for DNA solid film preparation, dispersion control in the laser cavity and subsequent characteristics of soliton pulses are discussed, to confirm unique nonlinear optical applications of DNA thin-solid-film.
Differentially expressed genes and canonical pathway expression in human atherosclerotic plaques – Tampere Vascular Study
Authors: Sulkava Miska , Raitoharju Emma , Levula Mari , Seppälä Ilkka , Lyytikäinen Leo-Pekka , Mennander Ari , Järvinen Otso , Zeitlin Rainer , Salenius Juha-Pekka , Illig Thomas , Klopp Norman , Mononen Nina , Laaksonen Reijo , Kähönen Mika , Oksala Niku , Lehtimäki Terho
Published: January 2017

Cardiovascular diseases due to atherosclerosis are the leading cause of death globally. We aimed to investigate the potentially altered gene and pathway expression in advanced peripheral atherosclerotic plaques in comparison to healthy control arteries. Gene expression analysis was performed (Illumina HumanHT-12 version 3 Expression BeadChip) for 68 advanced atherosclerotic plaques (15 aortic, 29 carotid and 24 femoral plaques) and 28 controls (left internal thoracic artery (LITA)) from Tampere Vascular Study. Dysregulation of individual genes was compared to healthy controls and between plaques from different arterial beds and Ingenuity pathway analysis was conducted on genes with a fold change (FC) > ±1.5 and false discovery rate (FDR) < 0.05. 787 genes were significantly differentially expressed in atherosclerotic plaques. The most up-regulated genes were osteopontin and multiple MMPs, and the most down-regulated were cell death-inducing DFFA-like effector C and A (CIDEC, CIDEA) and apolipoprotein D (FC > 20). 156 pathways were differentially expressed in atherosclerotic plaques, mostly inflammation-related, especially related with leukocyte trafficking and signaling. In artery specific plaque analysis 50.4% of canonical pathways and 41.2% GO terms differentially expressed were in common for all three arterial beds. Our results confirm the inflammatory nature of advanced atherosclerosis and show novel pathway differences between different arterial beds.
Modeling pre-metastatic lymphvascular niche in the mouse ear sponge assay
Authors: García-Caballero Melissa , Van de Velde Maureen , Blacher Silvia , Lambert Vincent , Balsat Cédric , Erpicum Charlotte , Durré Tania , Kridelka Frédéric , Noel Agnès
Published: January 2017

Lymphangiogenesis, the formation of new lymphatic vessels, occurs in primary tumors and in draining lymph nodes leading to pre-metastatic niche formation. Reliable in vivo models are becoming instrumental for investigating alterations occurring in lymph nodes before tumor cell arrival. In this study, we demonstrate that B16F10 melanoma cell encapsulation in a biomaterial, and implantation in the mouse ear, prevents their rapid lymphatic spread observed when cells are directly injected in the ear. Vascular remodeling in lymph nodes was detected two weeks after sponge implantation, while their colonization by tumor cells occurred two weeks later. In this model, a huge lymphangiogenic response was induced in primary tumors and in pre-metastatic and metastatic lymph nodes. In control lymph nodes, lymphatic vessels were confined to the cortex. In contrast, an enlargement and expansion of lymphatic vessels towards paracortical and medullar areas occurred in pre-metastatic lymph nodes. We designed an original computerized-assisted quantification method to examine the lymphatic vessel structure and the spatial distribution. This new reliable and accurate model is suitable for in vivo studies of lymphangiogenesis, holds promise for unraveling the mechanisms underlying lymphatic metastases and pre-metastatic niche formation in lymph nodes, and will provide new tools for drug testing.
Accessing the genomic information of unculturable oceanic picoeukaryotes by combining multiple single cells
Authors: Mangot Jean-François , Logares Ramiro , Sánchez Pablo , Latorre Fran , Seeleuthner Yoann , Mondy Samuel , Sieracki Michael E. , Jaillon Olivier , Wincker Patrick , Vargas Colomban de , Massana Ramon
Published: January 2017

Pico-sized eukaryotes play key roles in the functioning of marine ecosystems, but we still have a limited knowledge on their ecology and evolution. The MAST-4 lineage is of particular interest, since it is widespread in surface oceans, presents ecotypic differentiation and has defied culturing efforts so far. Single cell genomics (SCG) are promising tools to retrieve genomic information from these uncultured organisms. However, SCG are based on whole genome amplification, which normally introduces amplification biases that limit the amount of genomic data retrieved from a single cell. Here, we increase the recovery of genomic information from two MAST-4 lineages by co-assembling short reads from multiple Single Amplified Genomes (SAGs) belonging to evolutionary closely related cells. We found that complementary genomic information is retrieved from different SAGs, generating co-assembly that features >74% of genome recovery, against about 20% when assembled individually. Even though this approach is not aimed at generating high-quality draft genomes, it allows accessing to the genomic information of microbes that would otherwise remain unreachable. Since most of the picoeukaryotes still remain uncultured, our work serves as a proof-of-concept that can be applied to other taxa in order to extract genomic data and address new ecological and evolutionary questions.
A Circular Polarizer with Beamforming Feature Based on Frequency Selective Surfaces
Authors: Yin Jia Yuan , Wan Xiang , Ren Jian , Cui Tie Jun
Published: January 2017

We propose a circular polarizer with beamforming features based on frequency selective surface (FSS), in which a modified anchor-shaped unit cell is used to reach the circular polarizer function. The beamforming characteristic is realized by a particular design of the unit-phase distribution, which is obtained by varying the scale of the unit cell. Instead of using plane waves, a horn antenna is designed to feed the phase-variant FSS. The proposed two-layer FSS is fabricated and measured to verify the design. The measured results show that the proposed structure can convert the linearly polarized waves to circularly polarized waves. Compared with the feeding horn antenna, the transmitted beam of the FSS-added horn is 14.43° broader in one direction, while 3.77° narrower in the orthogonal direction. To our best knowledge, this is the first time to realize circular polarizer with beamforming as the extra function based on FSS, which is promising in satellite and communication systems for potential applications due to its simple design and good performance.
Oridonin Triggers Chaperon-mediated Proteasomal Degradation of BCR-ABL in Leukemia
Authors: Huang Huilin , Weng Hengyou , Dong Bowen , Zhao Panpan , Zhou Hui , Qu Lianghu
Published: January 2017

Inducing degradation of oncoproteins by small molecule compounds has the potential to avoid drug resistance and therefore deserves to be exploited for new therapies. Oridonin is a natural compound with promising antitumor efficacy that can trigger the degradation of oncoproteins; however, the direct cellular targets and underlying mechanisms remain unclear. Here we report that oridonin depletes BCR-ABL through chaperon-mediated proteasomal degradation in leukemia. Mechanistically, oridonin poses oxidative stress in cancer cells and directly binds to cysteines of HSF1, leading to the activation of this master regulator of the chaperone system. The resulting induction of HSP70 and ubiquitin proteins and the enhanced binding to CHIP E3 ligase hence target BCR-ABL for ubiquitin-proteasome degradation. Both wild-type and mutant forms of BCR-ABL can be efficiently degraded by oridonin, supporting its efficacy observed in cultured cells as well as mouse tumor xenograft assays with either imatinib-sensitive or -resistant cells. Collectively, our results identify a novel mechanism by which oridonin induces rapid degradation of BCR-ABL as well as a novel pharmaceutical activator of HSF1 that represents a promising treatment for leukemia.
Effects of Single-Dose Prucalopride on Intestinal Hypomotility in Horses: Preliminary Observations
Authors: Laus Fulvio , Fratini Margherita , Paggi Emanuele , Faillace Vanessa , Spaterna Andrea , Tesei Beniamino , Fettucciari Katia , Bassotti Gabrio
Published: January 2017

Abnormalities of gastrointestinal motility are often a challenge in horses; however, the use of prokinetic drugs in such conditions must be firmly established yet. For this reason we carried out a preliminary study on the effects of prucalopride on intestinal motor activity of horses with gut hypomotility. The effect of prucalopride per os by oral dose syringe (2 mg/100 kg body weight) was assessed by abdominal ultrasound (evaluating duodenal, cecal, and colonic motor activity) in six horses with gut hypomotility. After administration of prucalopride, a significant increase of contractile activity was found in the duodenum at 30 minutes (p = 0.0005), 60 minutes (p = 0.01) and 90 minutes (p = 0.01), whereas in the cecum and in the left colon the increase was only present at 60 minutes (p = 0.03, and p = 0.02, respectively). No changes from baseline heart and respiratory rate or behavior side effects were observed after administration of the drug and throughout the observation period. Prucalopride may be a useful adjunct to the therapeutic armamentary for treating hypomotile upper gut conditions of horses. Dosing information is however needed to establish its actual clinical efficacy and its proper effects on the large bowel in these animals.