bluuebunny/crossref_metadata_2025 huggingface dataset:
Geomagnetic reversal rates following Palaeozoic superchrons have a fast restart mechanism
Authors: Hounslow Mark W.
Published: August 2016

Long intervals of single geomagnetic polarity (superchrons) reflect geodynamo processes, driven by core–mantle boundary interactions; however, it is not clear what initiates the start and end of superchrons, other than superchrons probably reflect lower heat flow across the core–mantle boundary compared with adjacent intervals. Here geomagnetic polarity timescales, with confidence intervals, are constructed before and following the reverse polarity Kiaman (Carboniferous–Permian) and Moyero (Ordovician) superchrons, providing a window into the geodynamo processes. Similar to the Cretaceous, asymmetry in reversal rates is seen in the Palaeozoic superchrons, but the higher reversal rates imply higher heatflow thresholds for entering the superchron state. Similar to the Cretaceous superchron, unusually long-duration chrons characterize the ∼10 Myr interval adjacent to the superchrons, indicating a transitional reversing state to the superchrons. This may relate to a weak pattern in the clustering of chron durations superimposed on the dominant random arrangement of chron durations.
Environmental DNA reveals that rivers are conveyer belts of biodiversity information
Authors: Deiner Kristy , Fronhofer Emanuel A. , Mächler Elvira , Walser Jean-Claude , Altermatt Florian
Published: August 2016

DNA sampled from the environment (eDNA) is a useful way to uncover biodiversity patterns. By combining a conceptual model and empirical data, we test whether eDNA transported in river networks can be used as an integrative way to assess eukaryotic biodiversity for broad spatial scales and across the land–water interface. Using an eDNA metabarcode approach, we detect 296 families of eukaryotes, spanning 19 phyla across the catchment of a river. We show for a subset of these families that eDNA samples overcome spatial autocorrelation biases associated with the classical community assessments by integrating biodiversity information over space. In addition, we demonstrate that many terrestrial species are detected; thus suggesting eDNA in river water also incorporates biodiversity information across terrestrial and aquatic biomes. Environmental DNA transported in river networks offers a novel and spatially integrated way to assess the total biodiversity for whole landscapes and will transform biodiversity data acquisition in ecology.
Temperature-driven massless Kane fermions in HgCdTe crystals
Authors: Teppe F. , Marcinkiewicz M. , Krishtopenko S. S. , Ruffenach S. , Consejo C. , Kadykov A. M. , Desrat W. , But D. , Knap W. , Ludwig J. , Moon S. , Smirnov D. , Orlita M. , Jiang Z. , Morozov S. V. , Gavrilenko V.I. , Mikhailov N. N. , Dvoretskii S. A.
Published: August 2016

It has recently been shown that electronic states in bulk gapless HgCdTe offer another realization of pseudo-relativistic three-dimensional particles in condensed matter systems. These single valley relativistic states, massless Kane fermions, cannot be described by any other relativistic particles. Furthermore, the HgCdTe band structure can be continuously tailored by modifying cadmium content or temperature. At critical concentration or temperature, the bandgap collapses as the system undergoes a semimetal-to-semiconductor topological phase transition between the inverted and normal alignments. Here, using far-infrared magneto-spectroscopy we explore the continuous evolution of band structure of bulk HgCdTe as temperature is tuned across the topological phase transition. We demonstrate that the rest mass of Kane fermions changes sign at critical temperature, whereas their velocity remains constant. The velocity universal value of (1.07±0.05) × 106 m s−1 remains valid in a broad range of temperatures and Cd concentrations, indicating a striking universality of the pseudo-relativistic description of the Kane fermions in HgCdTe.
Efficient ex vivo analysis of CD4+ T-cell responses using combinatorial HLA class II tetramer staining
Authors: Uchtenhagen Hannes , Rims Cliff , Blahnik Gabriele , Chow I-Ting , Kwok William W. , Buckner Jane H. , James Eddie A.
Published: August 2016

MHC tetramers are an essential tool for characterizing antigen-specific CD4+ T cells. However, their ex vivo analysis is limited by the large sample requirements. Here we demonstrate a combinatorial staining approach that allows simultaneous characterization of multiple specificities to address this challenge. As proof of principle, we analyse CD4+ T-cell responses to the seasonal influenza vaccine, establishing a frequency hierarchy and examining differences in memory and activation status, lineage commitment and cytokine expression. We also observe cross-reactivity between an established epitope and recent variant and provide a means for probing T-cell receptor cross-reactivity. Using cord blood samples, we correlate the adult frequency hierarchy with the naive precursor frequencies. Last, we use our combinatorial staining approach to demonstrate that rheumatoid arthritis patients on therapy can mount effective responses to influenza vaccination. Together, these results demonstrate the utility of combinatorial tetramer staining and suggest that this approach may have broad applicability in human health and disease.
Source identification and distribution reveals the potential of the geochemical Antarctic sea ice proxy IPSO25
Authors: Belt S. T. , Smik L. , Brown T. A. , Kim J.-H. , Rowland S. J. , Allen C. S. , Gal J.-K. , Shin K.-H. , Lee J. I. , Taylor K. W. R.
Published: August 2016

The presence of a di-unsaturated highly branched isoprenoid (HBI) lipid biomarker (diene II) in Southern Ocean sediments has previously been proposed as a proxy measure of palaeo Antarctic sea ice. Here we show that a source of diene II is the sympagic diatomBerkeleya adeliensisMedlin. Furthermore, the propensity forB. adeliensisto flourish in platelet ice is reflected by an offshore downward gradient in diene II concentration in >100 surface sediments from Antarctic coastal and near-coastal environments. Since platelet ice formation is strongly associated with super-cooled freshwater inflow, we further hypothesize that sedimentary diene II provides a potentially sensitive proxy indicator of landfast sea ice influenced by meltwater discharge from nearby glaciers and ice shelves, and re-examination of some previous diene II downcore records supports this hypothesis. The term IPSO25—Ice Proxy for the Southern Ocean with 25 carbon atoms—is proposed as a proxy name for diene II.
Unveiling the geography of historical patents in the United States from 1836 to 1975
Authors: Petralia Sergio , Balland Pierre-Alexandre , Rigby David L.
Published: August 2016

It is clear that technology is a key driver of economic growth. Much less clear is where new technologies are produced and how the geography of U.S. invention has changed over the last two hundred years. Patent data report the geography, history, and technological characteristics of invention. However, those data have only recently become available in digital form and at the present time there exists no comprehensive dataset on the geography of knowledge production in the United States prior to 1975. The database presented in this paper unveils the geography of historical patents granted by the United States Patent and Trademark Office (USPTO) from 1836 to 1975. This historical dataset, HistPat, is constructed using digitalized records of original patent documents that are publicly available. We describe a methodological procedure that allows recovery of geographical information on patents from the digital records. HistPat can be used in different disciplines ranging from geography, economics, history, network science, and science and technology studies. Additionally, it is easily merged with post-1975 USPTO digital patent data to extend it until today.
PEG-lipid micelles enable cholesterol efflux in Niemann-Pick Type C1 disease-based lysosomal storage disorder
Authors: Brown Anna , Patel Siddharth , Ward Carl , Lorenz Anna , Ortiz Mauren , DuRoss Allison , Wieghardt Fabian , Esch Amanda , Otten Elsje G. , Heiser Laura M. , Korolchuk Viktor I. , Sun Conroy , Sarkar Sovan , Sahay Gaurav
Published: August 2016

2-Hydroxy-propyl-β-cyclodextrin (HPβCD), a cholesterol scavenger, is currently undergoing Phase 2b/3 clinical trial for treatment of Niemann Pick Type C-1 (NPC1), a fatal neurodegenerative disorder that stems from abnormal cholesterol accumulation in the endo/lysosomes. Unfortunately, the extremely high doses of HPβCD required to prevent progressive neurodegeneration exacerbates ototoxicity, pulmonary toxicity and autophagy-based cellular defects. We present unexpected evidence that a poly (ethylene glycol) (PEG)-lipid conjugate enables cholesterol clearance from endo/lysosomes of Npc1 mutant (Npc1−/−) cells. Herein, we show that distearyl-phosphatidylethanolamine-PEG (DSPE-PEG), which forms 12-nm micelles above the critical micelle concentration, accumulates heavily inside cholesterol-rich late endosomes in Npc1−/− cells. This potentially results in cholesterol solubilization and leakage from lysosomes. High-throughput screening revealed that DSPE-PEG, in combination with HPβCD, acts synergistically to efflux cholesterol without significantly aggravating autophagy defects. These well-known excipients can be used as admixtures to treat NPC1 disorder. Increasing PEG chain lengths from 350 Da-30 kDa in DSPE-PEG micelles, or increasing DSPE-PEG content in an array of liposomes packaged with HPβCD, improved cholesterol egress, while Pluronic block copolymers capable of micelle formation showed slight effects at high concentrations. We postulate that PEG-lipid based nanocarriers can serve as bioactive drug delivery systems for effective treatment of lysosomal storage disorders.
DBG2OLC: Efficient Assembly of Large Genomes Using Long Erroneous Reads of the Third Generation Sequencing Technologies
Authors: Ye Chengxi , Hill Christopher M. , Wu Shigang , Ruan Jue , Ma Zhanshan
Published: August 2016

The highly anticipated transition from next generation sequencing (NGS) to third generation sequencing (3GS) has been difficult primarily due to high error rates and excessive sequencing cost. The high error rates make the assembly of long erroneous reads of large genomes challenging because existing software solutions are often overwhelmed by error correction tasks. Here we report a hybrid assembly approach that simultaneously utilizes NGS and 3GS data to address both issues. We gain advantages from three general and basic design principles: (i) Compact representation of the long reads leads to efficient alignments. (ii) Base-level errors can be skipped; structural errors need to be detected and corrected. (iii) Structurally correct 3GS reads are assembled and polished. In our implementation, preassembled NGS contigs are used to derive the compact representation of the long reads, motivating an algorithmic conversion from a de Bruijn graph to an overlap graph, the two major assembly paradigms. Moreover, since NGS and 3GS data can compensate for each other, our hybrid assembly approach reduces both of their sequencing requirements. Experiments show that our software is able to assemble mammalian-sized genomes orders of magnitude more quickly than existing methods without consuming a lot of memory, while saving about half of the sequencing cost.
Correction: Corrigendum: Shielding of the Geomagnetic Field Alters Actin Assembly and Inhibits Cell Motility in Human Neuroblastoma Cells
Authors: Mo Wei-Chuan , Zhang Zi-Jian , Wang Dong-Liang , Liu Ying , Bartlett Perry F. , He Rong-Qiao
Published: August 2016

Scientific Reports 6: Article number: 22624; published online: 31 March 2016; updated: 30 August 2016 In this Article, Figures 5e-j are omitted. The Figure legend is correct. The correct Figure 5 appears below as Figure 1.
Intricate Plasma-Scattered Images and Spectra of Focused Femtosecond Laser Pulses
Authors: Ooi C. H. Raymond , Talib Md. Ridzuan
Published: August 2016

We report on some interesting phenomena in the focusing and scattering of femtosecond laser pulses in free space that provide insights on intense laser plasma interactions. The scattered image in the far field is analyzed and the connection with the observed structure of the plasma at the focus is discussed. We explain the physical mechanisms behind the changes in the colorful and intricate image formed by scattering from the plasma for different compressions, as well as orientations of plano-convex lens. The laser power does not show significant effect on the images. The pulse repetition rate above 500 Hz can affect the image through slow dynamics The spectrum of each color in the image shows oscillatory peaks due to interference of delayed pulse that correlate with the plasma length. Spectral lines of atomic species are identified and new peaks are observed through the white light emitted by the plasma spot. We find that an Ar gas jet can brighten the white light of the plasma spot and produce high resolution spectral peaks. The intricate image is found to be extremely sensitive and this is useful for applications in sensing microscale objects.
Anisotropic engineered heart tissue made from laser-cut decellularized myocardium
Authors: Schwan Jonas , Kwaczala Andrea T. , Ryan Thomas J. , Bartulos Oscar , Ren Yongming , Sewanan Lorenzo R. , Morris Aaron H. , Jacoby Daniel L. , Qyang Yibing , Campbell Stuart G.
Published: August 2016

We have developed an engineered heart tissue (EHT) system that uses laser-cut sheets of decellularized myocardium as scaffolds. This material enables formation of thin muscle strips whose biomechanical characteristics are easily measured and manipulated. To create EHTs, sections of porcine myocardium were laser-cut into ribbon-like shapes, decellularized and mounted in specialized clips for seeding and culture. Scaffolds were first tested by seeding with neonatal rat ventricular myocytes. EHTs beat synchronously by day five and exhibited robust length-dependent activation by day 21. Fiber orientation within the scaffold affected peak twitch stress, demonstrating its ability to guide cells toward physiologic contractile anisotropy. Scaffold anisotropy also made it possible to probe cellular responses to stretch as a function of fiber angle. Stretch that was aligned with the fiber direction increased expression of brain natriuretic peptide, but off-axis stretches (causing fiber shear) did not. The method also produced robust EHTs from cardiomyocytes derived from human embryonic stem cells and induced pluripotent stem cells (hiPSC). hiPSC-EHTs achieved maximum peak stress of 6.5 mN/mm2 and twitch kinetics approaching reported values from adult human trabeculae. We conclude that laser-cut EHTs are a viable platform for novel mechanotransduction experiments and characterizing the biomechanical function of patient-derived cardiomyoctyes.
Expression and Functional Analysis of a Novel Group of Legume-specific WRKY and Exo70 Protein Variants from Soybean
Authors: Wang Ze , Li Panfeng , Yang Yan , Chi Yingjun , Fan Baofang , Chen Zhixiang
Published: August 2016

Legumes fix atmospheric nitrogen through symbiosis with microorganisms and contain special traits in nitrogen assimilation and associated processes. Recently, we have reported a novel WRKY-related protein (GmWRP1) and a new clade of Exo70 proteins (GmExo70J) from soybean with homologs found only in legumes. GmWRP1 and some of the GmExo70J proteins are localized to Golgi apparatus through a novel N-terminal transmembrane domain. Here, we report further analysis of expression and functions of the novel GmWRP1 and GmExo70J genes. Promoter-GUS analysis in Arabidopsis revealed distinct tissue-specific expression patterns of the GmExo70J genes not only in vegetative but also in reproductive organs including mature tissues, where expression of previously characterized Exo70 genes is usually absent. Furthermore, expression of some GmExo70J genes including GmExo70J1, GmExo70J6 and GmExo70J7 increases greatly in floral organ-supporting receptacles during the development and maturation of siliques, indicating a possible role in seed development. More importantly, suppression of GmWRP1, GmExo70J7, GmExo70J8 and GmExo70J9 expression in soybean using virus- or artificial microRNA-mediated gene silencing resulted in accelerated leaf senescence and reduced nodule formation. These results strongly suggest that legume-specific GmWRP1 and GmExo70J proteins play important roles not only in legume symbiosis but also in other processes critical for legume growth and development.
The antifungal plant defensin AtPDF2.3 from Arabidopsis thaliana blocks potassium channels
Authors: Vriens Kim , Peigneur Steve , De Coninck Barbara , Tytgat Jan , Cammue Bruno P. A. , Thevissen Karin
Published: August 2016

Scorpion toxins that block potassium channels and antimicrobial plant defensins share a common structural CSαβ-motif. These toxins contain a toxin signature (K-C4-X-N) in their amino acid sequence, and based on in silico analysis of 18 plant defensin sequences, we noted the presence of a toxin signature (K-C5-R-G) in the amino acid sequence of the Arabidopsis thaliana defensin AtPDF2.3. We found that recombinant (r)AtPDF2.3 blocks Kv1.2 and Kv1.6 potassium channels, akin to the interaction between scorpion toxins and potassium channels. Moreover, rAtPDF2.3[G36N], a variant with a KCXN toxin signature (K-C5-R-N), is more potent in blocking Kv1.2 and Kv1.6 channels than rAtPDF2.3, whereas rAtPDF2.3[K33A], devoid of the toxin signature, is characterized by reduced Kv channel blocking activity. These findings highlight the importance of the KCXN scorpion toxin signature in the plant defensin sequence for blocking potassium channels. In addition, we found that rAtPDF2.3 inhibits the growth of Saccharomyces cerevisiae and that pathways regulating potassium transport and/or homeostasis confer tolerance of this yeast to rAtPDF2.3, indicating a role for potassium homeostasis in the fungal defence response towards rAtPDF2.3. Nevertheless, no differences in antifungal potency were observed between the rAtPDF2.3 variants, suggesting that antifungal activity and Kv channel inhibitory function are not linked.
Presynaptic DLG regulates synaptic function through the localization of voltage-activated Ca2+ Channels
Authors: Astorga César , Jorquera Ramón A. , Ramírez Mauricio , Kohler Andrés , López Estefanía , Delgado Ricardo , Córdova Alex , Olguín Patricio , Sierralta Jimena
Published: August 2016

The DLG-MAGUK subfamily of proteins plays a role on the recycling and clustering of glutamate receptors (GLUR) at the postsynaptic density. discs-large1 (dlg) is the only DLG-MAGUK gene in Drosophila and originates two main products, DLGA and DLGS97 which differ by the presence of an L27 domain. Combining electrophysiology, immunostaining and genetic manipulation at the pre and postsynaptic compartments we study the DLG contribution to the basal synaptic-function at the Drosophila larval neuromuscular junction. Our results reveal a specific function of DLGS97 in the regulation of the size of GLUR fields and their subunit composition. Strikingly the absence of any of DLG proteins at the presynaptic terminal disrupts the clustering and localization of the calcium channel DmCa1A subunit (Cacophony), decreases the action potential-evoked release probability and alters short-term plasticity. Our results show for the first time a crucial role of DLG proteins in the presynaptic function in vivo.
EF24 inhibits tumor growth and metastasis via suppressing NF-kappaB dependent pathways in human cholangiocarcinoma
Authors: Yin Da-long , Liang Ying-jian , Zheng Tong-sen , Song Rui-peng , Wang Jia-bei , Sun Bo-shi , Pan Shang-ha , Qu Lian-dong , Liu Jia-ren , Jiang Hong-chi , Liu Lian-xin
Published: August 2016

A synthetic monoketone analog of curcumin, termed 3, 5-bis (2-flurobenzylidene) piperidin-4-one (EF24), has been reported to inhibit the growth of a variety of cancer cells both in vitro and in vivo. However, whether EF24 has anticancer effects on cholangiocarcinoma (CCA) cells and the mechanisms remain to be investigated. The aim of our study was to evaluate the molecular mechanisms underlying the anticancer effects of EF24 on CCA tumor growth and metastasis. Cell proliferation, apoptosis, migration, invasion, tumorigenesis and metastasis were examined. EF24 exhibited time- and dose-dependent inhibitory effects on HuCCT-1, TFK-1 and HuH28 human CCA cell lines. EF24 inhibited CCA cell proliferation, migration, and induced G2/M phase arrest. EF24 induced cell apoptosis along with negative regulation of NF-κB- X-linked inhibitor of apoptosis protein (XIAP) signaling pathway. XIAP inhibition by lentivirus mediated RNA interference enhanced EF24-induced apoptosis, while XIAP overexpression reduced it in CCA cells. In vivo, EF24 significantly suppressed the growth of CCA tumor xenografts and tumor metastasis while displaying low toxicity levels. Our findings indicate that EF24 is a potent antitumor agent that inhibits tumor growth and metastasis by inhibiting NF-κB dependent signaling pathways. EF24 may represent a novel approach for CCA treatment.
Long noncoding RNA linc00598 regulates CCND2 transcription and modulates the G1 checkpoint
Authors: Jeong Oh-Seok , Chae Yun-Cheol , Jung Hyeonsoo , Park Soon Cheol , Cho Sung-Jin , Kook Hyun , Seo SangBeom
Published: August 2016

Data derived from genomic and transcriptomic analyses have revealed that long noncoding RNAs (lncRNAs) have important roles in the transcriptional regulation of various genes. Recent studies have identified the mechanism underlying this function. To date, a variety of noncoding transcripts have been reported to function in conjunction with epigenetic regulator proteins. In this study, we investigated the function of linc00598, which is transcribed by a genomic sequence on chromosome 13, downstream of FoxO1 and upstream of COG6. Microarray analysis showed that linc00598 regulates the transcription of specific target genes, including those for cell cycle regulators. We discovered that linc00598 regulates CCND2 transcription through modulation of the transcriptional regulatory effect of FoxO1 on the CCND2 promoter. Moreover, we observed that knockdown of linc00598 induced G0/G1 cell cycle arrest and inhibited proliferation. These data indicate that linc00598 plays an important role in cell cycle regulation and proliferation through its ability to regulate the transcription of CCND2.
Decreased demand for olfactory periglomerular cells impacts on neural precursor cell viability in the rostral migratory stream
Authors: Langenfurth Anika , Gu Song , Bautze Verena , Zhang Caiyi , Neumann Julia E. , Schüller Ulrich , Stock Kristin , Wolf Susanne A. , Maier Anna-Maria , Mastrella Giorgia , Pak Andrew , Cheng Hongwei , Kälin Roland E. , Holmbeck Kenn , Strotmann Jörg , Kettenmann Helmut , Glass Rainer
Published: August 2016

The subventricular zone (SVZ) provides a constant supply of new neurons to the olfactory bulb (OB). Different studies have investigated the role of olfactory sensory input to neural precursor cell (NPC) turnover in the SVZ but it was not addressed if a reduced demand specifically for periglomerular neurons impacts on NPC-traits in the rostral migratory stream (RMS). We here report that membrane type-1 matrix metalloproteinase (MT1-MMP) deficient mice have reduced complexity of the nasal turbinates, decreased sensory innervation of the OB, reduced numbers of olfactory glomeruli and reduced OB-size without alterations in SVZ neurogenesis. Large parts of the RMS were fully preserved in MT1-MMP-deficient mice, but we detected an increase in cell death-levels and a decrease in SVZ-derived neuroblasts in the distal RMS, as compared to controls. BrdU-tracking experiments showed that homing of NPCs specifically to the glomerular layer was reduced in MT1-MMP-deficient mice in contrast to controls while numbers of tracked cells remained equal in other OB-layers throughout all experimental groups. Altogether, our data show the demand for olfactory interneurons in the glomerular layer modulates cell turnover in the RMS, but has no impact on subventricular neurogenesis.
Phosphate enhance recovery from wastewater by mechanism analysis and optimization of struvite settleability in fluidized bed reactor
Authors: Fang Ci , Zhang Tao , Jiang Rongfeng , Ohtake Hisao
Published: August 2016

Since phosphorus, a non-renewable and non-substitutable resource, has become the principal contributor and limiting factor to water eutrophication, achieving phosphorus removal and recovery from wastewater is pretty essential. Even though struvite crystallization process has been widely used for phosphate (P) recovery in wastewater treatment, its application is hampered by difficulties controlling small particle size and crystal growth. This study was conducted to control the settleability of struvite by calculating and predicting the struvite-settling percentage (Ps), which is always affected by the initial concentration of P (CP), solution pH (pH), reaction time (t), reaction temperature (T), agitation rate (Ar) and inlet flow velocity (vf) of the fluidized bed reactor. The results showed that the settleability of struvite could be enhanced by increasing T and decreasing pH, Ar, or vf and would perform worse with overlong t or excessive CP. The dynamic variation process of the solution supersaturated index (SI) combined with the phase equilibrium theory and Ostwald ripening mechanism explained the above results sufficiently. The logistic model was chosen to predict the Ps under multi-factors, but the accuracy needs to be improved.
Exploring tight junction alteration using double fluorescent probe combination of lanthanide complex with gold nanoclusters
Authors: Wang Xinyi , Wang Na , Yuan Lan , Li Na , Wang Junxia , Yang Xiaoda
Published: August 2016

Tight junctions play a key role in restricting or regulating passage of liquids, ions and large solutes through various biological barriers by the paracellular route. Changes in paracellular permeation indicate alteration of the tight junction. However, it is very difficult to obtain the structural change information by measuring paracellular flux based on transepithelial electrical resistance or using fluorescein-labeled dextrans. Here we show that the BSA and GSH stabilized gold nanoclusters exhibit marginal cytotoxicity and pass through the MDCK monolayer exclusively through the paracellular pathway. We propose a double fluorescence probe strategy, the combination of a proven paracellular indicator (europium complex) with fluorescent gold nanoclusters. We calculate changes of structural parameters in tight junctions based on determination of the diffusion coefficients of the probes. Two different types of tight junction openers are used to validate our strategy. Results show that EDTA disrupts tight junction structures and induces large and smooth paracellular pore paths with an average radius of 17 nm, but vanadyl complexes induce paths with the radius of 6 nm. The work suggests that the double fluorescence probe strategy is a useful and convenient approach for in vitro investigation of tight junction structural alternations caused by pharmacological or pathological events.
Galectin-4 expression is down-regulated in response to autophagy during differentiation of rat trophoblast cells
Authors: Arikawa Tomohiro , Liao Shengjun , Shimada Hiroki , Inoue Tomoki , Sakata-Haga Hiromi , Nakamura Takanori , Hatta Toshihisa , Shoji Hiroki
Published: August 2016

Placental development and trophoblast invasion of the maternal endometrium establish the maternal-fetal interface, which is critical for the developing embryo and fetus. Herein we show that overexpression of Galectin-4 (Gal-4) during trophoblast differentiation inhibited the enlargement of Rcho-1 cells (a model for rat trophoblast differentiation) and promoted cell-cell adhesion, whereas trophoblast specific markers and MMP-9 activity were not affected. In the rat placenta, microtubule associated protein 1 light chain 3 alpha (LC3) protein, an autophagy marker, is highly expressed on the maternal side of the decidua where Gal-4 expression is weak. In vitro assays showed that the expression of trophoblast-specific differentiation markers was reduced by 3-Methyladenine (3-MA) and Bafilomycin A1, known as autophagy inhibitors, compared to control cells. Furthermore, Gal-4 expression in Rcho-1 cells, which is normally down-regulated during differentiation, was not attenuated in the presence of autophagy inhibitors, suggesting that autophagy is upstream of Gal-4 expression. We herein describe a possible mechanism by which autophagy regulates trophoblast differentiation via regulation of Gal-4 expression in order to establish the maternal-fetal interface.
Influence of tacrolimus metabolism rate on BKV infection after kidney transplantation
Authors: Thölking Gerold , Schmidt Christina , Koch Raphael , Schuette-Nuetgen Katharina , Pabst Dirk , Wolters Heiner , Kabar Iyad , Hüsing Anna , Pavenstädt Hermann , Reuter Stefan , Suwelack Barbara
Published: August 2016

Immunosuppression is the major risk factor for BK virus nephropathy (BKVN) after renal transplantation (RTx). As the individual tacrolimus (Tac) metabolism rate correlates with Tac side effects, we hypothesized that Tac metabolism might also influence the BKV infection risk. In this case-control study RTx patients with BK viremia within 4 years after RTx (BKV group) were compared with a BKV negative control group. The Tac metabolism rate expressed as the blood concentration normalized by the daily dose (C/D ratio) was applied to assess the Tac metabolism rate. BK viremia was detected in 86 patients after a median time of 6 (0–36) months after RTx. BKV positive patients showed lower Tac C/D ratios at 1, 3 and 6 months after RTx and were classified as fast Tac metabolizers. 8 of 86 patients with BK viremia had histologically proven BKN and a higher median maximum viral load than BKV patients without BKN (441,000 vs. 18,572 copies/mL). We conclude from our data that fast Tac metabolism (C/D ratio <1.05) is associated with BK viremia after RTx. Calculation of the Tac C/D ratio early after RTx, may assist transplant clinicians to identify patients at risk and to choose the optimal immunosuppressive regimen.
Time-dependent X-ray diffraction studies on urea/hen egg white lysozyme complexes reveal structural changes that indicate onset of denaturation
Authors: Raskar Tushar , Khavnekar Sagar , Hosur Madhusoodan
Published: August 2016

Temporal binding of urea to lysozyme was examined using X-ray diffraction of single crystals of urea/lysozyme complexes prepared by soaking native lysozyme crystals in solutions containing 9 M urea. Four different soak times of 2, 4, 7 and 10 hours were used. The five crystal structures (including the native lysozyme), refined to 1.6 Å resolution, reveal that as the soaking time increased, more and more first-shell water molecules are replaced by urea. The number of hydrogen bonds between urea and the protein is similar to that between protein and water molecules replaced by urea. However, the number of van der Waals contacts to protein from urea is almost double that between the protein and the replaced water. The hydrogen bonding and van der Waals interactions are initially greater with the backbone and later with side chains of charged residues. Urea altered the water-water hydrogen bond network both by replacing water solvating hydrophobic residues and by shortening the first-shell intra-water hydrogen bonds by 0.2 Å. These interaction data suggest that urea uses both ‘direct’ and ‘indirect’ mechanisms to unfold lysozyme. Specific structural changes constitute the first steps in lysozyme unfolding by urea.
Circulating intestine-derived exosomal miR-328 in plasma, a possible biomarker for estimating BCRP function in the human intestines
Authors: Gotanda Keisuke , Hirota Takeshi , Saito Jumpei , Fukae Masato , Egashira Yu , Izumi Noritomo , Deguchi Mariko , Kimura Miyuki , Matsuki Shunji , Irie Shin , Ieiri Ichiro
Published: August 2016

A variant in the breast cancer resistance protein (BCRP) gene, 421C> A is a useful biomarker for describing large inter-individual differences in the pharmacokinetics of sulfasalazine (SASP), a BCRP substrate. However, large intra-genotypic variability still exists in spite of the incorporation of this variant into the pharmacokinetics of SASP. Since miR-328 negatively regulates BCRP expression in human tissues, we hypothesized that exosomal miR-328 in plasma, which leaks from the intestines, is a possible biomarker for estimating BCRP activity in the human intestines. We established an immunoprecipitation-based quantitative method for circulating intestine-derived miR-328 in plasma using an anti-glycoprotein A33 antibody. A clinical study was conducted with an open-label, non-randomized and single-arm design involving 33 healthy participants. Intestine-derived exosomal miR-328 levels positively correlated (P < 0.05) with SASP AUC0-48, suggesting that subjects with high miR-328 levels have low intestinal BCRP activity, resulting in the high AUC of SASP. Circulating intestine-derived exosomal miR-328 in plasma has potential as a possible biomarker for estimating BCRP function in the human intestines.
Crystal Structure of Major Envelope Protein VP24 from White Spot Syndrome Virus
Authors: Sun Lifang , Su Yintao , Zhao Yanhe , Fu Zheng-qing , Wu Yunkun
Published: August 2016

White spot syndrome virus (WSSV) is one of the major and most serious pathogen in the shrimp industry. As one of the most abundant envelope protein, VP24 acts as a core protein interacting with other structure proteins and plays an important role in virus assembly and infection. Here, we have presented the crystal structure of VP24 from WSSV. In the structure, VP24 consists of a nine-stranded β–barrel fold with mostly antiparallel β-strands and the loops extending out the β–barrel at both N-terminus and C-terminus, which is distinct to those of the other two major envelope proteins VP28 and VP26. Structural comparison of VP24 with VP26 and VP28 reveals opposite electrostatic surface potential properties of them. These structural differences could provide insight into their differential functional mechanisms and roles for virus assembly and infection. Moreover, the structure reveals a trimeric assembly, suggesting a likely natural conformation of VP24 in viral envelope. Therefore, in addition to confirming the evolutionary relationship among the three abundant envelope proteins of WSSV, our structural studies also facilitate a better understanding of the molecular mechanism underlying special roles of VP24 in WSSV assembly and infection.
Broad Spectrum Anti-Influenza Agents by Inhibiting Self-Association of Matrix Protein 1
Authors: Mosier Philip D. , Chiang Meng-Jung , Lin Zhengshi , Gao Yamei , Althufairi Bashayer , Zhou Qibing , Musayev Faik , Safo Martin K. , Xie Hang , Desai Umesh R.
Published: August 2016

The matrix protein 1 (M1) of influenza A virus (IAV) exists as a three-dimensional oligomeric structure in mature virions with high sequence conservation across different IAV subtypes, which makes it a potential broad spectrum antiviral target. We hypothesized that impairing self-association of M1 through a small molecule ‘wedge’, which avidly binds to an M1-M1 interface, would result in a completely new class of anti-influenza agents. To establish this proof-of-principle, we performed virtual screening on a library of >70,000 commercially available small molecules that resulted in several plausible ‘wedges’. Biophysical studies showed that the best molecule bound the M1 protein potently and weakened M1-M1 self-association. Most importantly, the agent reduced the thickness of the M1 layer in mature virions and inhibited in ovo propagation of multiple IAV strains including H1N1, pandemic H1N1, H3N2 and H5N1, which supports the “wedge” hypothesis. These results demonstrate that M1 is a promising druggable target for the discovery of a completely new line of broad spectrum anti-IAV agents.
Introducing Mg-4Zn-3Gd-1Ca/ZnO nanocomposite with compressive strengths matching/exceeding that of mild steel
Authors: Chen Y. , Tekumalla S. , Guo Y. B. , Gupta M.
Published: August 2016

This work introduces Mg-4Zn-3Gd-1Ca/2ZnO (wt.%) nanocomposite fabricated using the technique of disintegrated melt deposition and extrusion. Addition of ZnO nanoparticles enhanced the compressive strengths of alloy by ~100 MPa. Nanocomposite samples display high strength and good ductility: 0.2% compressive yield stress of 355 MPa, ultimate compressive stress of 703 MPa and compressive failure strain of 10.6%. The significant enhancement of compressive yield stress is mainly attributed to the grain refinement by adding nanoparticles. The strength levels exceed that of commercial magnesium alloys (i.e. WE43, WE54, ZK60 and ME21) and mild steels (i.e. S275 and S355), making Mg-4Zn-3Gd-1Ca/2ZnO a very promising material for multiple engineering and biomedical applications.
PdCo/Pd-Hexacyanocobaltate Hybrid Nanoflowers: Cyanogel-Bridged One-Pot Synthesis and Their Enhanced Catalytic Performance
Authors: Liu Zhen-Yuan , Fu Geng-Tao , Zhang Lu , Yang Xiao-Yu , Liu Zhen-Qi , Sun Dong-Mei , Xu Lin , Tang Ya-Wen
Published: August 2016

Elaborate architectural manipulation of nanohybrids with multi-components into controllable 3D hierarchical structures is of great significance for both fundamental scientific interest and realization of various functionalities, yet remains a great challenge because different materials with distinct physical/chemical properties could hardly be incorporated simultaneously into the synthesis process. Here, we develop a novel one-pot cyanogel-bridged synthetic approach for the generation of 3D flower-like metal/Prussian blue analogue nanohybrids, namely PdCo/Pd-hexacyanocobaltate for the first time. The judicious introduction of polyethylene glycol (PEG) and the formation of cyanogel are prerequisite for the successful fabrication of such fascinating hierarchical nanostructures. Due to the unique 3D hierarchical structure and the synergistic effect between hybrid components, the as-prepared hybrid nanoflowers exhibit a remarkable catalytic activity and durability toward the reduction of Rhodamine B (RhB) by NaBH4. We expect that the obtained hybrid nanoflowers may hold great promises in water remediation field and beyond. Furthermore, the facile synthetic strategy presented here for synthesizing functional hybrid materials can be extendable for the synthesis of various functional hybrid nanomaterials owing to its versatility and feasibility.
Discharging a Li-S battery with ultra-high sulphur content cathode using a redox mediator
Authors: Kim Kwi Ryong , Lee Kug-Seung , Ahn Chi-Yeong , Yu Seung-Ho , Sung Yung-Eun
Published: August 2016

Lithium-sulphur batteries are under intense research due to the high specific capacity and low cost. However, several problems limit their commercialization. One of them is the insulating nature of sulphur, which necessitates a large amount of conductive agent and binder in the cathode, reducing the effective sulphur load as well as the energy density. Here we introduce a redox mediator, cobaltocene, which acts as an electron transfer agent between the conductive surface and the polysulphides in the electrolyte. We confirmed that cobaltocene could effectively convert polysulphides to Li2S using scanning electron microscope, X-ray absorption near-edge structure and in-situ X-ray diffraction studies. This redox mediator enabled excellent electrochemical performance in a cathode with ultra-high sulphur content (80 wt%). It delivered 400 mAh g−1cathode capacity after 50 cycles, which is equivalent to 800 mAh g−1S in a typical cathode with 50 wt% sulphur. Furthermore, the volumetric capacity was also dramatically improved.
Broadband terahertz metamaterial absorber based on sectional asymmetric structures
Authors: Gong Cheng , Zhan Mingzhou , Yang Jing , Wang Zhigang , Liu Haitao , Zhao Yuejin , Liu Weiwei
Published: August 2016

We suggest and demonstrate the concept and design of sectional asymmetric structures which can manipulate the metamaterial absorber’s working bandwidth with maintaining the other inherent advantages. As an example, a broadband terahertz perfect absorber is designed to confirm its effectiveness. The absorber’s each cell integrates four sectional asymmetric rings and the entire structure composed of Au and Si3N4 is only 1.9 μm thick. The simulation results show the bandwidth with absorptivity being larger than 90% is extended by about 2.8 times comparing with the conventional square ring absorber. The composable small cell, ultra-thin and broadband absorption with polarization and incident angle insensitivity will make the absorber suitable for the applications of focal plane array terahertz imaging.
Functionalized chitosan electrospun nanofiber for effective removal of trace arsenate from water
Authors: Min Ling-Li , Zhong Lu-Bin , Zheng Yu-Ming , Liu Qing , Yuan Zhi-Huan , Yang Li-Ming
Published: August 2016

An environment-friendly iron functionalized chitosan elctrospun nanofiber (ICS-ENF) was synthesized for trace arsenate removal from water. The ICS-ENF was fabricated by electrospinning a mixture of chitosan, PEO and Fe3+ followed by crosslinking with ammonia vapor. The physicochemical properties of ICS-ENF were characterized by FESEM, TEM-EDX and XRD. The ICS-ENF was found to be highly effective for As(V) adsorption at neutral pH. The As(V) adsorption occurred rapidly and achieved equilibrium within 100 min, which was well fitted by pseudo-second-order kinetics model. The As(V) adsorption decreased with increased ionic strength, suggesting an outer-sphere complexation of As(V) on ICS-ENF. Freundlich model well described the adsorption isotherm and the maximum adsorption capacity was up to 11.2 mg/g at pH 7.2. Coexisting anions of chloride and sulfate showed negligible influence on As(V) removal, but phosphate and silicate significantly reduced As(V) adsorption by competing for adsorption sites. FTIR and XPS analysis demonstrated –NH, –OH and C–O were responsible for As(V) uptake. ICS-ENF was easily regenerated using 0.003 M NaOH and the removal rate remained above 98% after ten successively adsorption-desorption recycles. This study extends the potential applicability of electrospun nanofibers for water purification and provides a promising approach for As(V) removal from water.
Pushing up the magnetisation values for iron oxide nanoparticles via zinc doping: X-ray studies on the particle's sub-nano structure of different synthesis routes
Authors: Szczerba Wojciech , Żukrowski Jan , Przybylski Marek , Sikora Marcin , Safonova Olga , Shmeliov Aleksey , Nicolosi Valeria , Schneider Michael , Granath Tim , Oppmann Maximilian , Straßer Marion , Mandel Karl
Published: August 2016

We study how only slightly different synthesis approaches towards zinc doped iron oxide nanoparticles strongly influences the resulting structure and magnetisation.
Bifunctional aryloxyphosphoramidate prodrugs of 2′-C-Me-uridine: synthesis and anti-HCV activity
Authors: Maiti Munmun , Gao Ling-Jie , Huang Chunsheng , Ptak Roger G. , Murray Michael G. , De Jonghe Steven , Herdewijn Piet
Published: August 2016

A series of l-glutamic acid, l-serine, l-threonine and l-tyrosine containing aryloxyphosphoramidate prodrugs of 2′-C-Me-uridine displayed very potent activity against HCV.
Racemic and enantioselective metal-catalyzed synthesis of SF5-containing diarylmethanols
Authors: Desroches Justine , Tremblay Ariane , Paquin Jean-François
Published: August 2016

The first racemic and enantioselective metal-catalyzed addition of arylboronic acids to 4- and 3-(pentafluorosulfur)benzaldehydes is reported.
An analysis of the experimental and theoretical charge density distributions of the piroxicam–saccharin co-crystal and its constituents
Authors: Du Jonathan J. , Váradi Linda , Williams Peter A. , Groundwater Paul W. , Overgaard Jacob , Platts James A. , Hibbs David E.
Published: August 2016

Experimental and theoretical charge density of piroxicam, saccharin and their 1 : 1 co-crystal have been determined using high-resolution X-ray diffraction, multipole refinement and DFT calculations
n-Bu4NI/TBHP-catalyzed C–N bond formation via cross-dehydrogenative coupling of 1H-1,2,4-triazoles (N–H) and methylarenes (Csp3–H)
Authors: Abebe Habtamu , Vidavalur Siddaiah , Battula Venkateswara Rao
Published: August 2016

An efficient n-Bu4NI/TBHP-catalyzed protocol for C–N bond formation via cross-dehydrogenative coupling of 1H-1,2,4-triazoles (N–H) and methylarenes (Csp3–H) has been developed under metal free conditions.
Coordinated frequency control from offshore wind power plants connected to multi terminal DC system considering wind speed variation
Authors: Sakamuri Jayachandra N. , Altin Müfit , Hansen Anca D. , Cutululis Nicolaos A.
Published: August 2016

A coordinated fast primary frequency control scheme from offshore wind power plants (OWPPs) integrated to a three terminal high voltage DC (HVDC) system is proposed in this study. The impact of wind speed variation on the OWPP active power output and thus on the AC grid frequency and DC grid voltage is analysed. The removal of active power support from OWPP after the frequency control action may result in second frequency (and DC voltage) dips. Three different methods to mitigate these secondary effects are proposed, such as, (i) Varying the droop gains of the HVDC converter (ii) Releasing the active power support from OWPP with a ramp rate limiter and (iii) An alternative method for the wind turbine overloading considering rotor speed. The effectiveness of the proposed control scheme is demonstrated on a wind power plant integrated into a three terminal HVDC system developed in DIgSILIENT PowerFactory. The results show that the proposed coordinated frequency control method performs effectively at different wind speeds and minimises the secondary effects on frequency and DC voltage.
Facile synthesis of water‐dispersible magnetite nanorings from surfactant‐free hematite nanorings
Authors: Zhang Yifan , Liu Xiaoli , Peng Erwin , Li Galong , Xiao Wen , Zhang Huan , Yu Baozhi , Wu Jianpeng , Luo Yane , Fan Haiming
Published: August 2016

Surfactant‐free α‐Fe2O3 nanorings (NRs) were directly converted into water‐dispersible Fe3O4NRs through a simple and straightforward approach. In this process, uniform α‐Fe2O3NRs obtained through hydrothermal synthesis method are firstly thermally reduced to hydrophobic Fe3O4NRs in the presence of hydrophobic oleic acid surfactant and non‐polar trioctylamine solvent (under a flow of 5% H2/95% Ar). Subsequently, oxidative cleavage of oleic acid capping agent using sodium periodate oxidising agent is imparted to yield water‐dispersible Fe3O4NRs. As compared with the traditional solid‐state reduction in tube furnace, the obtained Fe3O4NRs using solution‐based reduction process can retain its original uniform ring shape with good crystallinity and well‐defined magnetic vortex domain. Moreover, with the presence of azelaic acid on the surface of hydrophilic Fe3O4NRs, antibody or drugs can be easily conjugated, which further boost its potential theranostics application. This work provides a convenient approach to convert surfactant‐free nanoparticle (NP) powders into water‐dispersible NPs colloidal solutions for various biomedical applications.
Fabrication of large‐area ordered array of gold nanoparticles on c‐Si substrate and its characterisation through reflectance spectra
Authors: Meena Karishma , Kumar Hanish , Goswami Arjyajyoti , Aravindan Sivanandam , Rao Paruchuri Venkateshwara
Published: August 2016

Ordered arrays of substrate supported gold nanodots are fabricated on c‐Si as substrate. Electron beam lithography followed by DC sputter coating was used for the fabrication of ordered gold nanodots over a 1 × 1 cm2 area on c‐Si substrate. The fabricated ordered arrays of gold nanodots were characterised through the reflectance spectra. Reduction of 60.67% in reflectance was exhibited by ordered gold nanodots when compared with bare c‐Si. For comparison, a random gold nanoparticle array of approximately same particle size was fabricated and the reflectance was compared with the ordered array. It was found that the reflectance of ordered array is 52.27% less than that of random array. This route is suitable for fabrication of large area ordered gold nanodots which has applications in photovoltaic industry.