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Find video protocols related to scientific articles indexed in Pubmed.
Li3VO4 anchored graphene nanosheets for long-life and high-rate lithium-ion batteries.
Chem. Commun. (Camb.)
PUBLISHED: 11-20-2014
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Li3VO4 nanoparticles embedded in graphene nanosheets (Li3VO4@GNS) were obtained using a sol-gel method. The composite presents excellent high-rate performance with a stable capacity of 133 mA h g(-1) at 50 C and long-life performance with a capacity retention rate of 63.1% after 5000 cycles at 5 C.
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TCRklass: A New K-String-Based Algorithm for Human and Mouse TCR Repertoire Characterization.
J. Immunol.
PUBLISHED: 11-19-2014
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The next-generation sequencing technology has promoted the study on human TCR repertoire, which is essential for the adaptive immunity. To decipher the complexity of TCR repertoire, we developed an integrated pipeline, TCRklass, using K-string-based algorithm that has significantly improved the accuracy and performance over existing tools. We tested TCRklass using manually curated short read datasets in comparison with in silico datasets; it showed higher precision and recall rates on CDR3 identification. We applied TCRklass on large datasets of two human and three mouse TCR repertoires; it demonstrated higher reliability on CDR3 identification and much less biased V/J profiling, which are the two components contributing the diversity of the repertoire. Because of the sequencing cost, short paired-end reads generated by next-generation sequencing technology are and will remain the main source of data, and we believe that the TCRklass is a useful and reliable toolkit for TCR repertoire analysis.
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Novel radiotherapeutic bandage based on electrospun polyacrylonitrile containing holmium-166 iron garnet nanoparticles for the treatment of skin cancer.
ACS Appl Mater Interfaces
PUBLISHED: 11-15-2014
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It is currently estimated that one in every five Americans will develop skin cancer during their lifetime. Radiation therapy is used as a primary treatment for inoperable tumors and in patients that cannot or will not undergo surgery. Radioactive holmium-166 (166Ho) is a viable candidate for use against skin cancer. Non-radioactive holmium-165 (165Ho) iron garnet nanoparticles have been incorporated into a bandage, which, after neutron-activation to 166Ho, can be applied to a tumor lesion. The 165Ho iron garnet nanoparticles (165HoIG) were synthesized and introduced into poly-acrylonitrile (PAN) polymer solutions. The polymer solutions were then electrospun to produce flexible nonwoven bandages, which are stable to neutron-activation. The fiber mats were characterized using SEM, TEM, PXRD, FTIR, TGA and ICP-MS.
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A Prospective Study of Pain Control by a 2-Step Irradiance Schedule During Topical Photodynamic Therapy of Nonmelanoma Skin Cancer.
Dermatol Surg
PUBLISHED: 11-14-2014
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Topical photodynamic therapy (PDT) for selected nonmelanoma skin cancer using 5-aminolevulinic acid (ALA) or methyl aminolevulinate (MAL) has yielded high long-term complete response rates with very good cosmesis. Pain during light activation of the photosensitizer can be a serious adverse event. A 2-step irradiance protocol has previously been shown to minimize ALA-PDT pain.
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Enabling the 'host jump': structural determinants of receptor-binding specificity in influenza A viruses.
Nat. Rev. Microbiol.
PUBLISHED: 11-10-2014
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The recent emergence of the H7N9 avian influenza A virus and its ability to infect humans emphasize the epidemic and pandemic potential of these viruses. Interspecies transmission is the result of many factors, which ultimately lead to a change in the host tropism of the virus. One of the key factors involved is a shift in the receptor-binding specificity of the virus, which is mostly determined by mutations in the viral haemagglutinin (HA). In this Review, we discuss recent crystallographic studies that provide molecular insights into HA-host receptor interactions that have enabled several influenza A virus subtypes to 'jump' from avian to human hosts.
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Novel Avian-Origin Influenza A (H7N9) in Critically Ill Patients in China.
Crit. Care Med.
PUBLISHED: 11-04-2014
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In March 2013, human infection with a novel avian-origin reassortment influenza A (H7N9) virus was identified in China. A total of 26 cases were confirmed and treated in Jiangsu. All the patients had findings consistent with pneumonia and were admitted to an ICU, which pose a threat to human health. We aimed to provide the clinical features, treatment, and prognosis of the critically ill patients with H7N9 viral infection.
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In-plane epitaxial growth of silicon nanowires and junction formation on si(100) substrates.
Nano Lett.
PUBLISHED: 10-30-2014
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Growing self-assembled silicon nanowires (SiNWs) into precise locations represents a critical capability to scale up SiNW-based functionalities. We here report a novel epitaxy growth phenomenon and strategy to fabricate orderly arrays of self-aligned in-plane SiNWs on Si(100) substrates following exactly the underlying crystallographic orientations. We observe also a rich set of distinctive growth dynamics/modes that lead to remarkably different morphologies of epitaxially grown SiNWs/or grains under variant growth balance conditions. High-resolution transmission electron microscopy cross-section analysis confirms a coherent epitaxy (or partial epitaxy) interface between the in-plane SiNWs and the Si(100) substrate, while conductive atomic force microscopy characterization reveals that electrically rectifying p-n junctions are formed between the p-type doped in-plane SiNWs and the n-type c-Si(100) substrate. This in-plane epitaxy growth could provide an effective means to define nanoscale junction and doping profiles, providing a basis for exploring novel nanoelectronics.
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Intracellular NAMPT-NAD+-SIRT1 cascade improves post-ischaemic vascular repair by modulating Notch signalling in endothelial progenitors.
Cardiovasc. Res.
PUBLISHED: 10-25-2014
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Intracellular nicotinamide phosphoribosyltransferase (NAMPT) is the rate-limiting enzyme for nicotinamide adenine dinucleotide (NAD(+)) biosynthesis. This study investigated the role of NAMPT-mediated NAD(+) signalling in post-ischaemic vascular repair.
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[Methylation of Runx3 promoter in different breast lesions].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 10-21-2014
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To investigate the methylation status of Runx3 promoter and Runx3 expression in breast lesion tissues.
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Metastasis mechanism and gene/protein expression in gastric cancer with distant organs metastasis.
Bull Cancer
PUBLISHED: 10-09-2014
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Metastasis is the most fatal characteristics of malignancy tumor, which accounted for more than 90% of tumor-related mortality. Distant organ or tissue metastasis is a sign of poor prognosis in patients with gastric cancer. Tumor cells metastasis is a very complex process including tumor cell transformation, growth, angiogenesis, invasion, dissemination and survival in the circulation, and subsequent adhesion and colonization the secondary organ or tissue. The origin of tumor cell, genetic variation, the circulatory mode and the physiological structure of the metastatic organ determines the specific sites of distant metastasis. In theory, the metastatic lesion is originated from their primary tumor, so they should have the same molecular profile with the primary tumor. But this view has been confirmed to be wrong in various tumors, including gastric cancer. The gene expression of primary gastric cancer and its metastasis have differences, which may contribute to the early diagnosis and individualized treatment of metastasis. However, the heterogeneity of tumor cells is still unclear in different metastasis lesion of gastric cancer, which will be a major focus of future research. In this review, we discuss the basic principles of cancer metastasis, the unique physiological characteristics of the various metastasis organs and the expression of different functions of gene/protein in primary and metastasis of gastric cancer. In addition, we also discuss the diagnosis, prognosis and treatment in various organ metastasis of gastric cancer.
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Microbiota in the throat and risk factors of laryngeal carcinoma.
Appl. Environ. Microbiol.
PUBLISHED: 09-21-2014
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The compositions and abundance of the microbiota in the ecological niche of human throat and their possible relationship between the microbiota and laryngeal cancer are poorly understood. To obtain insight into this, we enrolled 27 laryngeal carcinoma patients and 28 subjects with vocal cord polyps as controls. For each subject, we simultaneously collected swab samples from the upper throat near epiglottis (site I) and tissue samples from the vestibulum laryngis to the subglottic region (site II). The microbiota of the throat were fully characterized by pyrosequencing of barcoded 16S rRNA genes. We found 14 phyla, 20 classes, 38 orders, 85 families, and 218 genera in the throat of enrolled subjects. The main phyla were Firmicutes (54.7%), Fusobacteria (14.8%), Bacteroidetes (12.7%), and Proteobacteria (10.6%). Streptococcus (37.3%), Fusobacterium (11.3%), and Prevotella (10.6%) were identified as the three most predominant genera in the throat. The relative abundances of 23 bacterial genera in the site I were significantly different compared with the site II (p < 0.05). The relative proportions of 12 genera largely varied between laryngeal cancer patients and control subjects (p < 0.05). Collectively, this study outlined the spatial structure of microbial communities in the human throat. The spatial structure of bacterial communities significantly varied in two anatomical sites of the throat. The bacterial profiles in the throat were strongly different between laryngeal cancer patients and control subjects, and several of these microorganisms may be related to laryngeal carcinoma.
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Genetic association study between INSULIN pathway related genes and high myopia in a Han Chinese population.
Mol. Biol. Rep.
PUBLISHED: 09-20-2014
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To investigate the association between insulin (INS) pathway related genes, including INS, insulin receptor (INSR), insulin receptor substrate 1 (IRS1), insulin-like growth factor 2 (IGF2), IGF2 receptor (IGF2R) and IGF binding protein 1 (IGFBP1), and high myopia (HM) in a Han Chinese population, we have genotyped 24 single nucleotide polymorphisms (SNPs) of these genes in this cohort by Sequenom MassARRAY method. The genotyping data was analyzed by ?(2) test and the linkage disequilibrium block structure was examined by Haploview software. SNPs in the INS-IGF2 region (rs2070762 and rs1003483), and the INSR gene (rs3745551 and rs2229429) showed significant association with HM (allelic P = 0.0085, 0.0494, 0.0171 and 0.0238, respectively). Under the model of risk genotype combination of INSR and IRS1, carrying the variant allele (A) of the IRS1 Gly972Arg SNP (rs1801278) further increased the risk among the rs2229429T allele carriers (odds ratio 6.865, 95 % confidence interval 1.533-30.745). None of the SNPs in the IGF2R and IGFBP1 genes were found to be significantly associated with HM. Genetic variants in the insulin signaling pathway genes may increase the susceptibility of high myopia in Han Chinese.
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Synthesis of phenanthrenes through copper-catalyzed cross-coupling of N-tosylhydrazones with terminal alkynes.
J. Org. Chem.
PUBLISHED: 09-03-2014
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A novel protocol for the synthesis of phenanthrenes through the copper-catalyzed reaction of aromatic tosylhydrazones with terminal alkynes is explored. The reaction proceeds via the formation of an allene intermediate and subsequent six-?-electron cyclization-isomerization, affording phenanthrene derivatives in good yields. The transformation can be performed in two ways: (1) with N-tosylhydrazones derived from [1,1'-biphenyl]-2-carbaldehydes and terminal alkynes as the starting materials and (2) with N-tosylhydrazones derived from aromatic aldehydes and 2-alkynyl biphenyls as the starting materials. This new phenanthrene synthesis uses readily available starting materials and a cheap copper catalyst and has a wide range of functional group compatibility.
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Neuronal representation of working memory in the medial prefrontal cortex of rats.
Mol Brain
PUBLISHED: 08-28-2014
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Working memory is a process for short-term active maintenance of information. Behavioral neurophysiological studies in monkeys have demonstrated that the dorsolateral prefrontal cortex (dlPFC) is a key cortical region for working memory. The medial prefrontal cortex (mPFC) in rats is a cortical area similar to the dlPFC in monkeys in terms of anatomical connections, and is also required for behavioral performance on working-memory tasks. However, it is still controversial regarding whether and how mPFC neurons encode working memory. In the present study, we trained rats on a two-choice spatial delayed alternation task in Y maze, a typical working memory task for rodents, and investigated neuronal activities in the mPFC when rats performed the task. Our results show that, (1) inactivation of the mPFC severely impaired the performance of rats on the task, consistent with previous studies showing the importance of the mPFC for working-memory tasks; (2) 93.7% mPFC cells (449 in 479) exhibited changes in spiking frequency that were temporally locked with the task events, some of which, including delay-related cells, were tuned by spatial information; (3) differential delay activities in individual mPFC cells appeared transiently and sequentially along the delay, especially during the early phase of the delay; (4) some mPFC cells showed no change in discharge frequency but exhibited differential synchronization in firing during the delay. The present results suggest that mPFC neurons in rats are involved in encoding working memory, via increasing firing frequency or synchronization.
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Structural Characterization by Cross-linking Reveals the Detailed Architecture of a Coatomer-related Heptameric Module from the Nuclear Pore Complex.
Mol. Cell Proteomics
PUBLISHED: 08-26-2014
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Most cellular processes are orchestrated by macromolecular complexes. However, structural elucidation of these endogenous complexes can be challenging because they frequently contain large numbers of proteins, are compositionally and morphologically heterogeneous, can be dynamic, and are often of low abundance in the cell. Here, we present a strategy for the structural characterization of such complexes that has at its center chemical cross-linking with mass spectrometric readout. In this strategy, we isolate the endogenous complexes using a highly optimized sample preparation protocol and generate a comprehensive, high-quality cross-linking dataset using two complementary cross-linking reagents. We then determine the structure of the complex using a refined integrative method that combines the cross-linking data with information generated from other sources, including electron microscopy, X-ray crystallography, and comparative protein structure modeling. We applied this integrative strategy to determine the structure of the native Nup84 complex, a stable hetero-heptameric assembly (?600 kDa), 16 copies of which form the outer rings of the 50-MDa nuclear pore complex (NPC) in budding yeast. The unprecedented detail of the Nup84 complex structure reveals previously unseen features in its pentameric structural hub and provides information on the conformational flexibility of the assembly. These additional details further support and augment the protocoatomer hypothesis, which proposes an evolutionary relationship between vesicle coating complexes and the NPC, and indicates a conserved mechanism by which the NPC is anchored in the nuclear envelope.
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Giant cell interstitial pneumonia: unusual lung disorder and an update.
Chin. Med. J.
PUBLISHED: 08-23-2014
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Giant cell interstitial pneumonia (GIP) was a rare form of pneumoconiosis, associated with exposure to hard metals, which had been reported mostly as isolated case reports. We described eight cases of GIP diagnosed in our hospital during the past seven years, with particular reference to new findings.
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Integrative structure-function mapping of the nucleoporin nup133 suggests a conserved mechanism for membrane anchoring of the nuclear pore complex.
Mol. Cell Proteomics
PUBLISHED: 08-19-2014
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The nuclear pore complex (NPC) is the sole passageway for the transport of macromolecules across the nuclear envelope. Nup133, a major component in the essential Y-shaped Nup84 complex, is a large scaffold protein of the NPC's outer ring structure. Here, we describe an integrative modeling approach that produces atomic models for multiple states of Saccharomyces cerevisiae (Sc) Nup133, based on the crystal structures of the sequence segments and their homologs, including the related Vanderwaltozyma polyspora (Vp) Nup133 residues 55 to 502 (VpNup133(55-502)) determined in this study, small angle X-ray scattering profiles for 18 constructs of ScNup133 and one construct of VpNup133, and 23 negative-stain electron microscopy class averages of ScNup133(2-1157). Using our integrative approach, we then computed a multi-state structural model of the full-length ScNup133 and validated it with mutational studies and 45 chemical cross-links determined via mass spectrometry. Finally, the model of ScNup133 allowed us to annotate a potential ArfGAP1 lipid packing sensor (ALPS) motif in Sc and VpNup133 and discuss its potential significance in the context of the whole NPC; we suggest that ALPS motifs are scattered throughout the NPC's scaffold in all eukaryotes and play a major role in the assembly and membrane anchoring of the NPC in the nuclear envelope. Our results are consistent with a common evolutionary origin of Nup133 with membrane coating complexes (the protocoatomer hypothesis); the presence of the ALPS motifs in coatomer-like nucleoporins suggests an ancestral mechanism for membrane recognition present in early membrane coating complexes.
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Rhodium-Catalyzed NH Insertion of Pyridyl Carbenes Derived from Pyridotriazoles: A General and Efficient Approach to 2-Picolylamines and Imidazo[1,5-a]pyridines.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-18-2014
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A general and efficient NH insertion reaction of rhodium pyridyl carbenes derived from pyridotriazoles was developed. Various NH-containing compounds, including amides, anilines, enamines, and aliphatic amines, smoothly underwent the NH insertion reaction to afford 2-picolylamine derivatives. The developed transformation was further utilized in a facile one-pot synthesis of imidazo[1,5-a]pyridines.
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Two-dimensional quasi-freestanding molecular crystals for high-performance organic field-effect transistors.
Nat Commun
PUBLISHED: 08-18-2014
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Two-dimensional atomic crystals are extensively studied in recent years due to their exciting physics and device applications. However, a molecular counterpart, with scalable processability and competitive device performance, is still challenging. Here, we demonstrate that high-quality few-layer dioctylbenzothienobenzothiophene molecular crystals can be grown on graphene or boron nitride substrate via van der Waals epitaxy, with precisely controlled thickness down to monolayer, large-area single crystal, low process temperature and patterning capability. The crystalline layers are atomically smooth and effectively decoupled from the substrate due to weak van der Waals interactions, affording a pristine interface for high-performance organic transistors. As a result, monolayer dioctylbenzothienobenzothiophene molecular crystal field-effect transistors on boron nitride show record-high carrier mobility up to 10?cm(2)?V(-1)?s(-1) and aggressively scaled saturation voltage ~1?V. Our work unveils an exciting new class of two-dimensional molecular materials for electronic and optoelectronic applications.
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A pharmacogenetics-based warfarin maintenance dosing algorithm from Northern Chinese patients.
PLoS ONE
PUBLISHED: 08-15-2014
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Inconsistent associations with warfarin dose were observed in genetic variants except VKORC1 haplotype and CYP2C9*3 in Chinese people, and few studies on warfarin dose algorithm was performed in a large Chinese Han population lived in Northern China. Of 787 consenting patients with heart-valve replacements who were receiving long-term warfarin maintenance therapy, 20 related Single nucleotide polymorphisms were genotyped. Only VKORC1 and CYP2C9 SNPs were observed to be significantly associated with warfarin dose. In the derivation cohort (n?=?551), warfarin dose variability was influenced, in decreasing order, by VKORC1 rs7294 (27.3%), CYP2C9*3(7.0%), body surface area(4.2%), age(2.7%), target INR(1.4%), CYP4F2 rs2108622 (0.7%), amiodarone use(0.6%), diabetes mellitus(0.6%), and digoxin use(0.5%), which account for 45.1% of the warfarin dose variability. In the validation cohort (n?=?236), the actual maintenance dose was significantly correlated with predicted dose (r?=?0.609, P<0.001). Our algorithm could improve the personalized management of warfarin use in Northern Chinese patients.
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Tristetraprolin is involved in the glucocorticoid-mediated interleukin 8 repression.
Int. Immunopharmacol.
PUBLISHED: 08-08-2014
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Glucocorticoids have been widely used in various inflammatory disorders, and the transcriptional repression of inflammatory mediators has been considered to be the main mechanism of action. However, a previous study showed that dexamethasone inhibited interleukin 8 (IL-8) expression by promoting IL-8 mRNA decay, which implies a posttranscriptional regulation. Nevertheless, by which mechanism dexamethasone destabilized IL-8 mRNA was unclear. Another study indicated that an RNA-binding protein, tristetraprolin (TTP), could be induced by dexamethasone. TTP can bind to AU-rich elements (ARE) in the 3'-untranslated region of target mRNAs and promotes mRNA degradation. So, we speculated that dexamethasone destabilized IL-8 mRNA by upregulating TTP expression. Here, we report that dexamethasone reduced IL-8 expression through destabilizing IL-8 mRNA in human pulmonary microvascular endothelial cells (HPMECs). Dexamethasone stimulation increased TTP mRNA and protein levels. TTP silencing led to mRNA stabilization and protein upregulation of IL-8. These results provide the evidence that the glucocorticoid, in HPMECs, inhibits IL-8 expression through TTP at the posttranscriptional level.
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Molecular Architecture and Function of the SEA Complex, a Modulator of the TORC1 Pathway.
Mol. Cell Proteomics
PUBLISHED: 07-29-2014
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The TORC1 signaling pathway plays a major role in the control of cell growth and response to stress. Here we demonstrate that the SEA complex physically interacts with TORC1 and is an important regulator of its activity. During nitrogen starvation, deletions of SEA complex components lead to Tor1 kinase delocalization, defects in autophagy, and vacuolar fragmentation. TORC1 inactivation, via nitrogen deprivation or rapamycin treatment, changes cellular levels of SEA complex members. We used affinity purification and chemical cross-linking to generate the data for an integrative structure modeling approach, which produced a well-defined molecular architecture of the SEA complex and showed that the SEA complex comprises two regions that are structurally and functionally distinct. The SEA complex emerges as a platform that can coordinate both structural and enzymatic activities necessary for the effective functioning of the TORC1 pathway.
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Structural stability of E. coli trigger factor studied by synchrotron small-angle X-ray scattering.
Biophys. Chem.
PUBLISHED: 07-26-2014
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Solution small-angle X-ray scattering (SAXS) is an effective technique for quantitatively measuring the compactness and shape of proteins. We use SAXS to study the structural characteristics and unfolding transitions induced by urea for full length Escherichia coli trigger factor (TF) and a series of truncation mutants, obtaining and comparing the radiuses of gyration (Rg), the distance-distribution function (P(r) function) and integrated intensity of TF variants in native and unfolding states. The C-terminal 72-residue truncated mutant TF360 exhibited dramatic structural differences and reduced stability compared with the whole TF molecule, while the N-domain truncated mutant MC maintained its compact structure with reduced stability. These results indicate that the C-terminal region of TF plays an important role in the structural and conformational stabilities of the TF molecule, while the N-domain is relatively independent.
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Reconstitution of active human core Mediator complex reveals a critical role of the MED14 subunit.
Nat. Struct. Mol. Biol.
PUBLISHED: 07-24-2014
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The evolutionarily conserved Mediator complex is a critical coactivator for RNA polymerase II (Pol II)-mediated transcription. Here we report the reconstitution of a functional 15-subunit human core Mediator complex and its characterization by functional assays and chemical cross-linking coupled to MS (CX-MS). Whereas the reconstituted head and middle modules can stably associate, basal and coactivator functions are acquired only after incorporation of MED14 into the bimodular complex. This results from a dramatically enhanced ability of MED14-containing complexes to associate with Pol II. Altogether, our analyses identify MED14 as both an architectural and a functional backbone of the Mediator complex. We further establish a conditional requirement for metazoan-specific MED26 that becomes evident in the presence of heterologous nuclear factors. This general approach paves the way for systematic dissection of the multiple layers of functionality associated with the Mediator complex.
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Peptide-dependent conformational fluctuation determines the stability of the human leukocyte antigen class I complex.
J. Biol. Chem.
PUBLISHED: 07-15-2014
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In immune-mediated control of pathogens, human leukocyte antigen (HLA) class I presents various antigenic peptides to CD8(+) T-cells. Long-lived peptide presentation is important for efficient antigen-specific T-cell activation. Presentation time depends on the peptide sequence and the stability of the peptide-HLA complex (pHLA). However, the determinant of peptide-dependent pHLA stability remains elusive. Here, to reveal the pHLA stabilization mechanism, we examined the crystal structures of an HLA class I allomorph in complex with HIV-derived peptides and evaluated site-specific conformational fluctuations using NMR. Although the crystal structures of various pHLAs were almost identical independent of the peptides, fluctuation analyses identified a peptide-dependent minor state that would be more tightly packed toward the peptide. The minor population correlated well with the thermostability and cell surface presentation of pHLA, indicating that this newly identified minor state is important for stabilizing the pHLA and facilitating T-cell recognition.
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Multifunctional superhydrophobic surfaces templated from innately microstructured hydrogel matrix.
Nano Lett.
PUBLISHED: 06-30-2014
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Superhydrophobic surfaces are of immense scientific and technological interests for a broad range of applications. However, a major challenge remains in developing scalable methodologies that enable superhydrophobic coatings on versatile substrates with a combination of strong mechanical stability, optical transparency, and even stretchability. Herein, we developed a scalable methodology to versatile hydrophobic surfaces that combine with strong mechanical stability, optical transparency, and stretchability by using a self-assembled hydrogel as the template to in situ generate silica microstructures and subsequent silanization. The superhydrophobic coatings can be enabled on virtually any substrates via large-area deposition techniques like dip coating. Transparent surfaces with optical transmittance as high as 98% were obtained. Moreover, the coatings exhibit superior mechanical flexibility and robustness that it can sustain contact angles ? 160° even after 5000 cycles of mechanically stretching at 100% strain. The multifunctional surfaces can be used as screen filters and sponges for the oil/water separation that can selectively absorb oils up to 40× their weight.
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Gas sensors based on semiconducting nanowire field-effect transistors.
Sensors (Basel)
PUBLISHED: 06-29-2014
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One-dimensional semiconductor nanostructures are unique sensing materials for the fabrication of gas sensors. In this article, gas sensors based on semiconducting nanowire field-effect transistors (FETs) are comprehensively reviewed. Individual nanowires or nanowire network films are usually used as the active detecting channels. In these sensors, a third electrode, which serves as the gate, is used to tune the carrier concentration of the nanowires to realize better sensing performance, including sensitivity, selectivity and response time, etc. The FET parameters can be modulated by the presence of the target gases and their change relate closely to the type and concentration of the gas molecules. In addition, extra controls such as metal decoration, local heating and light irradiation can be combined with the gate electrode to tune the nanowire channel and realize more effective gas sensing. With the help of micro-fabrication techniques, these sensors can be integrated into smart systems. Finally, some challenges for the future investigation and application of nanowire field-effect gas sensors are discussed.
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CNOT7/hCAF1 is involved in ICAM-1 and IL-8 regulation by tristetraprolin.
Cell. Signal.
PUBLISHED: 06-25-2014
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Tristetraprolin (TTP) is an RNA-binding protein which can bind to the AU-rich elements (AREs) at the 3'-untranslated region (3'-UTR) of target mRNA and promote mRNA deadenylation and degradation. We have shown in a previous study that TTP regulates tumor necrosis factor-? (TNF-?)-induced expression of intercellular adhesion molecule-1 (ICAM-1) and interleukin-8 (IL-8), both of whose mRNAs have AREs in the 3'-UTR, in human pulmonary microvascular endothelial cells (HPMEC) through destabilizing target mRNAs, nevertheless, the mechanism by which TTP promotes mRNA decay remains unclear. Observations have indicated that TTP can interact with CAF1 (CNOT7/hCAF1 in human), a subunit of the CCR4-NOT complex with deadenylase activity. Another study illustrated that TTP can directly bind to CNOT1, the scaffold subunit of the CCR4-NOT complex. The present study showed that TTP bound to the AREs of ICAM-1 and IL-8 mRNAs and was coimmunoprecipitated with intracellular ICAM-1 and IL-8 mRNAs. TTP, CNOT7 and CNOT1 were coimmunoprecipitated in HPMEC. CNOT7 silencing stabilized ICAM-1 and IL-8 mRNAs and increased ICAM-1 and IL-8 production following TNF-? stimulation. These results, together with our previous study, suggest that CNOT7/hCAF1 is involved in ICAM-1 and IL-8 regulation by TTP in HPMEC.
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tRNA synthetase counteracts c-Myc to develop functional vasculature.
Elife
PUBLISHED: 06-19-2014
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Recent studies suggested an essential role for seryl-tRNA synthetase (SerRS) in vascular development. This role is specific to SerRS among all tRNA synthetases and is independent of its well-known aminoacylation function in protein synthesis. A unique nucleus-directing domain, added at the invertebrate-to-vertebrate transition, confers this novel non-translational activity of SerRS. Previous studies showed that SerRS, in some unknown way, controls VEGFA expression to prevent vascular over-expansion. Using in vitro, cell and animal experiments, we show here that SerRS intervenes by antagonizing c-Myc, the major transcription factor promoting VEGFA expression, through a tandem mechanism. First, by direct head-to-head competition, nuclear-localized SerRS blocks c-Myc from binding to the VEGFA promoter. Second, DNA-bound SerRS recruits the SIRT2 histone deacetylase to erase prior c-Myc-promoted histone acetylation. Thus, vertebrate SerRS and c-Myc is a pair of 'Yin-Yang' transcriptional regulator for proper development of a functional vasculature. Our results also discover an anti-angiogenic activity for SIRT2.DOI: http://dx.doi.org/10.7554/eLife.02349.001.
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Mst1 regulates glioma cell proliferation via the AKT/mTOR signaling pathway.
J. Neurooncol.
PUBLISHED: 06-05-2014
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Mammalian sterile 20-like 1 (Mst1), an upstream serine/threonine-specific protein kinase of the Hippo pathway, is reported to play important roles in tumor suppression and organ size regulation in mammals via regulating cell proliferation and survival. However, whether it is involved in the pathogenesis of malignant gliomas remains poorly understood. Therefore, in the present work, we examined the effect and mechanism of Mst1 on the proliferation and apoptosis of malignant glioma cells. The cell proliferation and growth of glioma cells were examined by EdU incorporation and CCK-8 assay. In addition, the cell apoptosis was assessed by flow cytometry. We found that down-regulation of Mst1 promoted glioma cell proliferation and growth, but inhibited the cell apoptosis. Consistent with this, over-expression of Mst1 inhibited glioma cell proliferation and growth. Interestingly, Mst1 did not affect the phosphorylation of YAP1, the key downstream molecule of Hippo pathway. However, Mst1 was found to bind to AKT in glioma cell and negatively regulated AKT and mTOR activity. Finally, the increased cell proliferation rate induced by Mst1 down-regulation was partially abolished by down-regulation of AKT1. Meanwhile, glioma cell growth inhibition induced by Mst1 over-expression was partially rescued by over-expression of AKT1. Taken together, these findings suggest that Mst1 regulates proliferation of glioma cells via AKT/mTOR signaling pathway.
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Superimposed epitopes restricted by the same HLA molecule drive distinct HIV-specific CD8+ T cell repertoires.
J. Immunol.
PUBLISHED: 06-04-2014
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Superimposed epitopes, in which a shorter epitope is embedded within a longer one, can be presented by the same HLA class I molecule. CD8(+) CTL responses against such epitopes and the contribution of this phenomenon to immune control are poorly characterized. In this study, we examined HLA-A*24:02-restricted CTLs specific for the superimposed HIV Nef epitopes RYPLTFGWCF (RF10) and RYPLTFGW (RW8). Unexpectedly, RF10-specific and RW8-specific CTLs from HIV-1-infected HLA-A*24:02+ individuals had no overlapping Ag reactivity or clonotypic compositions. Single-cell TCR sequence analyses demonstrated that RF10-specific T cells had a more diverse TCR repertoire than did RW8-specific T cells. Furthermore, RF10-specific CTLs presented a higher Ag sensitivity and HIV suppressive capacity compared with RW8-specific CTLs. Crystallographic analyses revealed important structural differences between RF10- and RW8-HLA-A*24:02 complexes as well, with featured and featureless conformations, respectively, providing an explanation for the induction of distinct T cell responses against these epitopes. The present study shows that a single viral sequence containing superimposed epitopes restricted by the same HLA molecule could elicit distinct CD8+ T cell responses, therefore enhancing the control of HIV replication. This study also showed that a featured epitope (e.g., RF10) could drive the induction of T cells with high TCR diversity and affinity.
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Towards intrinsic charge transport in monolayer molybdenum disulfide by defect and interface engineering.
Nat Commun
PUBLISHED: 06-02-2014
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Molybdenum disulfide is considered as one of the most promising two-dimensional semiconductors for electronic and optoelectronic device applications. So far, the charge transport in monolayer molybdenum disulfide is dominated by extrinsic factors such as charged impurities, structural defects and traps, leading to much lower mobility than the intrinsic limit. Here we develop a facile low-temperature thiol chemistry route to repair the sulfur vacancies and improve the interface, resulting in significant reduction of the charged impurities and traps. High mobility >80?cm(2)?V(-1)?s(-1) is achieved in backgated monolayer molybdenum disulfide field-effect transistors at room temperature. Furthermore, we develop a theoretical model to quantitatively extract the key microscopic quantities that control the transistor performances, including the density of charged impurities, short-range defects and traps. Our combined experimental and theoretical study provides a clear path towards intrinsic charge transport in two-dimensional dichalcogenides for future high-performance device applications.
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Decision making after BRCA genetic testing. Down the road of transition.
Clin J Oncol Nurs
PUBLISHED: 05-29-2014
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The purpose of this study was to evaluate women who have completed hereditary cancer risk assessment and BRCA genetic testing to determine if they considered themselves prepared to proceed with decision making regarding cancer screening and prevention options. Levels of decisional conflict were explored, as was their preference for information delivery. The prospective, descriptive survey was conducted at a breast and clinical genetics clinic at a comprehensive cancer center in the northeastern United States. Twenty-seven female participants completed the Preparation for Decision Making scale, Decisional Conflict Scale, and a demographic questionnaire. Scores were consistent with high levels of preparation for decision making and low decisional conflict. The face-to-face approach was the preferred method for information delivery. Subgroup analysis demonstrated a difference in the measured objectives based on cancer status but not based on BRCA status. The current information delivery approach is meeting the decision-making needs of women considered to be at increased risk for hereditary breast and ovarian cancer.
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Enhanced age-dependent cerebrovascular dysfunction is mediated by adaptor protein p66Shc.
Int. J. Cardiol.
PUBLISHED: 05-22-2014
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Aging is an independent risk factor for cardiovascular and cerebrovascular disease. To date, little is known about the mechanisms of aging of cerebral arteries and whether the aging gene p66(Shc) is implicated in it. The present study was designed to assess age-induced vascular dysfunction in cerebral and systemic arteries of wild type (wt) and p66(Shc-/-) mice.
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Enhanced toxicity of cisplatin with chemosensitizer phenethyl isothiocyanate toward non-small cell lung cancer cells when delivered in liposomal nanoparticles.
Chem. Res. Toxicol.
PUBLISHED: 05-20-2014
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Naturally occurring phenethyl isothiocyanate (PEITC) was previously shown to sensitize human non-small cell lung cancer (NSCLC) cells to the platinum anticancer drug cisplatin (CDDP). Here, CDDP and PEITC were encapsulated in approximately 130 nm liposomes composed of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and L-?-phosphatidylglycerol (EPG). The liposomal formulation enhanced the toxicity of this doublet (1:2 molar ratio of CDDP/PEITC) toward NCI-H596 NSCLC cells; the percent survival of cells was 30.2±6.2% after treatment with the nanoparticle formulation, compared to 50.9±3.5% when administered together free. Thus, such a treatment modality could prove useful in the clinic for the treatment of NSCLC.
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N?-terminal acetylation for T cell recognition: molecular basis of MHC class I-restricted n?-acetylpeptide presentation.
J. Immunol.
PUBLISHED: 05-14-2014
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As one of the most common posttranslational modifications (PTMs) of eukaryotic proteins, N(?)-terminal acetylation (Nt-acetylation) generates a class of N(?)-acetylpeptides that are known to be presented by MHC class I at the cell surface. Although such PTM plays a pivotal role in adjusting proteolysis, the molecular basis for the presentation and T cell recognition of N(?)-acetylpeptides remains largely unknown. In this study, we determined a high-resolution crystallographic structure of HLA (HLA)-B*3901 complexed with an N(?)-acetylpeptide derived from natural cellular processing, also in comparison with the unmodified-peptide complex. Unlike the ?-amino-free P1 residues of unmodified peptide, of which the ?-amino group inserts into pocket A of the Ag-binding groove, the N(?)-linked acetyl of the acetylated P1-Ser protrudes out of the groove for T cell recognition. Moreover, the Nt-acetylation not only alters the conformation of the peptide but also switches the residues in the ?1-helix of HLA-B*3901, which may impact the T cell engagement. The thermostability measurements of complexes between N(?)-acetylpeptides and a series of MHC class I molecules derived from different species reveal reduced stability. Our findings provide the insight into the mode of N(?)-acetylpeptide-specific presentation by classical MHC class I molecules and shed light on the potential of acetylepitope-based immune intervene and vaccine development.
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Evaluation of MYOC, ACAN, HGF, and MET as candidate genes for high myopia in a Han Chinese population.
Genet Test Mol Biomarkers
PUBLISHED: 04-25-2014
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To investigate the association between high myopia (HM) and single nucleotide polymorphisms (SNPs) in the myocilin (MYOC), hepatocyte growth factor (HGF), hepatocyte growth factor receptor (MET), and aggrecan (ACAN) genes in a Han Chinese population.
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Oxidative Stress Diverts tRNA Synthetase to Nucleus for Protection against DNA Damage.
Mol. Cell
PUBLISHED: 04-18-2014
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Tyrosyl-tRNA synthetase (TyrRS) is known for its essential aminoacylation function in protein synthesis. Here we report a function for TyrRS in DNA damage protection. We found that oxidative stress, which often downregulates protein synthesis, induces TyrRS to rapidly translocate from the cytosol to the nucleus. We also found that angiogenin mediates or potentiates this stress-induced translocalization. The nuclear-localized TyrRS activates transcription factor E2F1 to upregulate the expression of DNA damage repair genes such as BRCA1 and RAD51. The activation is achieved through direct interaction of TyrRS with TRIM28 to sequester this vertebrate-specific epigenetic repressor and its associated HDAC1 from deacetylating and suppressing E2F1. Remarkably, overexpression of TyrRS strongly protects against UV-induced DNA double-strand breaks in zebrafish, whereas restricting TyrRS nuclear entry completely abolishes the protection. Therefore, oxidative stress triggers an essential cytoplasmic enzyme used for protein synthesis to translocate to the nucleus to protect against DNA damage.
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Telomerase gene mutations and telomere length shortening in patients with idiopathic pulmonary fibrosis in a Chinese population.
Respirology
PUBLISHED: 04-17-2014
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Idiopathic pulmonary fibrosis (IPF) is an age-related disease and the most common manifestation of telomere-mediated disorders.
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Analysis of influenza virus receptor specificity using glycan-functionalized gold nanoparticles.
ACS Nano
PUBLISHED: 04-15-2014
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Recent cases of human infection with avian influenza H5N1 and H7N9 viruses underscore an urgent need for techniques that can rapidly assess their potential threat to the humans. Determination of the receptor-binding property of influenza virus is crucial to direct viral control and prevention measures. Current methods to perform this analysis are dependent on immunoanalytical strategies that use unstable biological components and complex procedures. We have developed a facile colorimetric assay to determine the interaction of the viral hemagglutinin (HA) protein with host glycan receptors using glycan-functionalized gold nanoparticles (gGNPs). This method is based on the color and absorbance changes of gold probes when the solution is simply mixed with HAs or intact viruses. The resulting sensitivity and selectivity has enabled HA/virus binding to various glycan structures to be differentiated visually and rapidly. Using this system, we have screened, in parallel, the receptor specificity of eight representative human and avian viral HAs and three whole viruses including an emerging H7N9 strain. Our results reveal the detailed receptor-binding profiles of H7N9 virus and its HA and show that they effectively bind to human-type receptors. This gGNP-based assay represents a strategy that would be helpful for developing simple and sensitive systems to probe glycan-mediated biological processes.
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[Analysis of COL9A2 gene mutations in a Chinese Han population with pathological myopia].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 04-09-2014
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To analyze the mutation of COL9A2 gene and investigate the molecular pathogenesis of pathological myopia in a Han Chinese population.
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Prevalence and risk of viral infection in patients with acute exacerbation of chronic obstructive pulmonary disease: a meta-analysis.
Mol. Biol. Rep.
PUBLISHED: 03-21-2014
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Exacerbations of chronic obstructive pulmonary disease (COPD) lead to substantial morbidity and mortality. Viral infections could be an important cause of acute exacerbations of COPD (AECOPD) and only a few studies report the prevalence of respiratory viruses on this disease. We aimed to update the review on the prevalence of respiratory viral infection in patients with AECOPD with a meta-analysis. We reviewed the prevalence of respiratory viruses on this disease by searching PubMed systematically to identify primary studies published from Jan 1990 to March 2012. Studies met with seven criteria were extracted for meta-analysis. A total of 17 studies were eligible for the meta-analysis. Weighted overall prevalence of respiratory viruses in patients with AECOPD was 39.3% (95% CI 36.9-41.6) with a high degree of a heterogeneity (I (2) > 75%). In contrast, the rate in stable COPD patients from four studies was 13.6% (95% CI 9.0-18.2) without any apparent heterogeneity. Pooled risk ratio for respiratory viral infection was 4.1 (95% CI 2.0-8.5) for AECOPD as compared with stable COPD. Rhinovirus was the most common virus and with a weighted prevalence of 14.8% (95% CI 13.3-16.5). Respiratory viruses probably are important etiological agents in patients with AECOPD as compared with the stable COPD patients. This result would help to provide better strategies for management of AECOPD and health-care planning.
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Metastasis mechanism and gene/protein expression in gastric cancer with distant organs metastasis.
Bull Cancer
PUBLISHED: 03-21-2014
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Metastasis is the most fatal characteristics of malignancy tumor, which accounted for more than 90% of tumor-related mortality. Distant organ or tissue metastasis is a sign of poor prognosis in patients with gastric cancer. Tumor cells metastasis is a very complex process including tumor cell transformation, growth, angiogenesis, invasion, dissemination and survival in the circulation, and subsequent adhesion and colonization the secondary organ or tissue. The origin of tumor cell, genetic variation, the circulatory mode and the physiological structure of the metastatic organ determines the specific sites of distant metastasis. In theory, the metastatic lesion is originated from their primary tumor, so they should have the same molecular profile with the primary tumor. But this view has been confirmed to be wrong in various tumors, including gastric cancer. The gene expression of primary gastric cancer and its metastasis have differences, which may contribute to the early diagnosis and individualized treatment of metastasis. However, the heterogeneity of tumor cells is still unclear in different metastasis lesion of gastric cancer, which will be a major focus of future research. In this review, we discuss the basic principles of cancer metastasis, the unique physiological characteristics of the various metastasis organs and the expression of different functions of gene/protein in primary and metastasis of gastric cancer. In addition, we also discuss the diagnosis, prognosis and treatment in various organ metastasis of gastric cancer.
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Inorganic proton conducting electrolyte coupled oxide-based dendritic transistors for synaptic electronics.
Nanoscale
PUBLISHED: 03-20-2014
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Ionic/electronic hybrid devices with synaptic functions are considered to be the essential building blocks for neuromorphic systems and brain-inspired computing. Here, artificial synapses based on indium-zinc-oxide (IZO) transistors gated by nanogranular SiO2 proton-conducting electrolyte films are fabricated on glass substrates. Spike-timing dependent plasticity and paired-pulse facilitation are successfully mimicked in an individual bottom-gate transistor. Most importantly, dynamic logic and dendritic integration established by spatiotemporally correlated spikes are also mimicked in dendritic transistors with two in-plane gates as the presynaptic input terminals.
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Utilizing water characteristics and sediment nitrogen isotopic features to identify non-point nitrogen pollution sources at watershed scale in Liaoning Province, China.
Environ Sci Pollut Res Int
PUBLISHED: 02-25-2014
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Identifying nitrogen (N) pollution sources is the fundamental work of non-point source pollution load reduction from watersheds, but is hard due to complex N transport and transformation within spatially heterogenized huge areas. During September 2011, we measured water characteristics and sediment N stable isotope in four tributaries of the upper reach of the Hun River, an important water source of the Dahuofang Reservoir, a large drinking water source in Northeast China. Results showed that spatial changes in SO4 (2-) and Cl(-) contents in the tributaries were consisted with the changes in density of the population living along the tributaries. Sediment ?(15)N from all tributaries showed a downstream increasing trend in line with the land use change, which is characterized as more farmlands and more people around the outlet area of each tributary. Principal component analysis indicated the population density had a strong impact on N in these tributaries in the low-flow period. Tributaries and villages close to the Dahuofang Reservoir should be the major N load control objects in reduction of non-point source nitrogen load from the upper reach of the Hun River.
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Understanding light harvesting in radial junction amorphous silicon thin film solar cells.
Sci Rep
PUBLISHED: 02-25-2014
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The radial junction (RJ) architecture has proven beneficial for the design of a new generation of high performance thin film photovoltaics. We herein carry out a comprehensive modeling of the light in-coupling, propagation and absorption profile within RJ thin film cells based on an accurate set of material properties extracted from spectroscopic ellipsometry measurements. This has enabled us to understand and evaluate the impact of varying several key parameters on the light harvesting in radially formed thin film solar cells. We found that the resonance mode absorption and antenna-like light in-coupling behavior in the RJ cell cavity can lead to a unique absorption distribution in the absorber that is very different from the situation expected in a planar thin film cell, and that has to be taken into account in the design of high performance RJ thin film solar cells. When compared to the experimental EQE response of real RJ solar cells, this modeling also provides an insightful and powerful tool to resolve the wavelength-dependent contributions arising from individual RJ units and/or from strong light trapping due to the presence of the RJ cell array.
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A screening strategy for phenotypic detection of carbapenemase in the clinical laboratory.
Can. J. Microbiol.
PUBLISHED: 02-20-2014
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Nosocomial infections caused by carbapenemase-producing Enterobacteriaceae have emerged as an important challenge worldwide and represent a great limitation for antimicrobial therapy. Detection of carbapenemase in Enterobacteriaceae species also remains challenging. Although the modified Hodge test is recommended, it lacks specificity and is unable to distinguish between carbapenemase types. Here, we demonstrated a screening strategy for the phenotypic detection of carbapenemases among Enterobacteriaceae isolates in the clinical laboratory by using ethylenediaminetetraacetic acid and phenylboronic acid. This strategy displayed an overall 100% sensitivity and 98.6% specificity for carbapenemase detection in Enterobacteriaceae, which was superior to that of the modified Hodge test (98.0% sensitivity and 84.3% specificity), and it also discriminated the carbapenemase phenotypes of KPC-2, VIM-1, and OXA-48.
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Health-related quality of life outcomes after robot-assisted and open radical cystectomy using a validated bladder-specific instrument: a multi-institutional study.
Urology
PUBLISHED: 02-13-2014
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To evaluate health-related quality of life (HRQL) using validated bladder-specific Bladder Cancer Index (BCI) and European Organization for Research and Treatment of Cancer Body Image scale (BIS) between open radical cystectomy (ORC) and robot-assisted radical cystectomy (RARC).
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Tunable, ultralow-power switching in memristive devices enabled by a heterogeneous graphene-oxide interface.
Adv. Mater. Weinheim
PUBLISHED: 01-18-2014
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Memristive devices based on vertical heterostructures of graphene and TiOx show a significant power reduction that is up to ?10(3) times smaller than that of conventional structures. This power reduction arises as a result of a tunneling barrier at the interface. The barrier is tunable, opening up the possibility of engineering several key memory characteristics.
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Anti-HMGB1 neutralizing antibody ameliorates neutrophilic airway inflammation by suppressing dendritic cell-mediated Th17 polarization.
Mediators Inflamm.
PUBLISHED: 01-17-2014
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We demonstrate that high mobility group box 1 protein (HMGB1) directs Th17 skewing by regulating dendritic cell (DC) function. First, our in vitro studies reveal that recombinant HMGB1 (rHMGB1) activates myeloid DCs to produce IL-23 in vitro, and rHMGB1-activated DCs prime naïve lymphocytes to produce the Th17 cytokine IL-17A. Second, we demonstrate that anti-HMGB1 neutralizing antibody attenuates HMGB1 expression, neutrophilic inflammation, airway hyperresponsiveness, and Th17-related cytokine secretion in vivo by using a murine model of neutrophilic asthma induced by ovalbumin (OVA) plus lipopolysaccharide (LPS). Furthermore, anti-HMGB1 neutralizing antibody decreases the number of Th17 cells in lung cells and suppresses the production of IL-23 by lung CD11C(+) APCs. Finally, we show that intranasal adoptive transfer of rHMGB1-activated DCs was sufficient to restore lung neutrophilic inflammation and the Th17 response in a DC-driven model of asthma, whereas the transfer of rHMGB1 plus anti-HMGB1-treated mDCs significantly reduced these inflammation phenotypes. These data suggest, for the first time, that HMGB1 drives the DC-polarized Th17-type response in allergic lung inflammation and that blocking HMGB1 may benefit the attenuation of neutrophilic airway inflammation in asthma.
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H7N9: a low pathogenic avian influenza A virus infecting humans.
Curr Opin Virol
PUBLISHED: 01-13-2014
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Human infections by the newly reassorted avian influenza A (H7N9) virus were reported for the first time in early 2013, and the virus was confirmed to be a low pathogenic avian influenza virus in poultry. Because continuously reported cases have been increasing since the summer of 2013, this novel virus poses a potential threat to public health in China and is attracting broad attention worldwide. In this review, we summarize and discuss the characteristics of the H7N9 virus revealed by the recent timely studies from the perspectives of epidemiology, host preference, clinical manifestations, immunopathogenesis, drug resistance, vaccine development, and burden of disease. This knowledge about the novel avian-origin H7N9 virus will provide a useful reference for clinical interventions of human infections and help to rapidly pave the way to develop an efficient and safe vaccine.
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The mechanism of the one-step synthesis of hollow-structured Li(3)VO(4) as an anode for lithium-ion batteries.
Chemistry
PUBLISHED: 01-10-2014
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In recent years, the controlled synthesis of inorganic micro- and nanostructures with hollow interiors has attracted considerable attention because of their widespread potential applications. A feasible method for synthesizing Li3 VO4 by a template-free, solution synthesis of single-crystalline microboxes with well-defined non-spherical morphologies has been reported. This study provides the useful information to produce other hollow structure materials to the broad audience of readers. The formation of hollow structure and the influence of raw materials have been presented. The thus-synthesized Li3 VO4 exhibited significantly improved conductivity, rate capability, and cycling life compared to commercial graphite, synthesized Li4 Ti5 O12 , and previously reported Li3 VO4 .
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Efficacy of combination therapy of triazole and echinocandin in treatment of invasive aspergillosis: a systematic review of animal and human studies.
J Thorac Dis
PUBLISHED: 01-06-2014
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The effectiveness of the combination therapy of triazole and echinocandin in treatment of invasive aspergillosis (IA) remains controversial. The objective of this systematic review was to assess the efficacy of combination therapy of triazole and echinocandin in treatment of IA.
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Construct validation of the key components of Fundamental Skills of Robotic Surgery (FSRS) curriculum--a multi-institution prospective study.
J Surg Educ
PUBLISHED: 01-02-2014
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Recent incorporation of simulation in surgical training necessitates developing validated platforms for training and assessment. A tool should fulfill the fundamental criteria of validation.
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Dual role of endothelial nitric oxide synthase in oxidized LDL-induced, p66Shc-mediated oxidative stress in cultured human endothelial cells.
PLoS ONE
PUBLISHED: 01-01-2014
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The aging gene p66Shc, is an important mediator of oxidative stress-induced vascular dysfunction and disease. In cultured human aortic endothelial cells (HAEC), p66Shc deletion increases endothelial nitric oxide synthase (eNOS) expression and nitric oxide (NO) bioavailability via protein kinase B. However, the putative role of the NO pathway on p66Shc activation remains unclear. This study was designed to elucidate the regulatory role of the eNOS/NO pathway on p66Shc activation.
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Vitamin D deficiency causes defective resistance to Aspergillus fumigatus in mice via aggravated and sustained inflammation.
PLoS ONE
PUBLISHED: 01-01-2014
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Vitamin D plays an important role in pulmonary resistance and immunity, and its deficiency has been linked to various respiratory infections. Little is known about the effect of vitamin D deficiency on host pulmonary defense to Aspergillus fumigatus (A. fumigatus).
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Genetic variants in PVRL2-TOMM40-APOE region are associated with human longevity in a Han Chinese population.
PLoS ONE
PUBLISHED: 01-01-2014
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Human longevity results from a number of factors, including genetic background, favorable environmental, social factors and chance. In this study, we aimed to elucidate the association of human longevity with genetic variations in several major candidate genes in a Han Chinese population.
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CARP is a potential tumor suppressor in gastric carcinoma and a single-nucleotide polymorphism in CARP gene might increase the risk of gastric carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
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The caspase-associated recruitment domain-containing protein (CARP) is expressed in almost all tissues. Recently, the tumor-suppressive function of CARP was discovered and attracted increasing attention. This study aimed to investigate the role of CARP in the carcinogenesis of human gastric carcinoma.
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Cardiac troponin I is abnormally expressed in non-small cell lung cancer tissues and human cancer cells.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Cardiac troponin I (cTnI) is the only sarcomeric protein identified to date that is expressed exclusively in cardiac muscle. Its expression in cancer tissues has not been reported. Herein, we examined cTnI expression in non-small cell lung cancer (NSCLC) tissues, human adenocarcinoma cells SPCA-1 (lung) and BGC 823 (gastric) by immunohistochemistry, western blot analysis and real-time PCR. Immunopositivity for cTnI was demonstrated in 69.4% (34/49) NSCLC tissues evaluated, and was strong intensity in 35.3% (6/17) lung squamous cell carcinoma cases. The non-cancer-bearing lung tissues except tuberculosis (9/9, 100%) showed negative staining for cTnI. Seven monoclonal antibodies (mAbs) against human cTnI were applied in immunofluorescence. The result showed that the staining pattern within SPCA-1 and BGC 823 was dependent on the epitope of the cTnI mAbs. The membrane and nucleus of cancer cells were stained by mAbs against N-terminal peptides of cTnI, and cytoplasm was stained by mAbs against the middle and C-terminal peptides of cTnI. A ~25 kD band was identified by anti-cTnI mAb in SPCA-1 and BGC 823 extracts by western blot, as well as in cardiomyocyte extracts. The cTnI mRNA expressions in SPCA-1 and BGC 823 cells were about ten thousand times less than that in cardiomyocytes. Our study shows for the first time that cTnI protein and mRNA were abnormally expressed in NSCLC tissues, SPCA-1 and BGC 823 cells. These findings challenge the conventional view of cTnI as a cardiac-specific protein, enabling the potential use of cTnI as a diagnostic marker or targeted therapy for cancer.
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Expert consensus on acute exacerbation of chronic obstructive pulmonary disease in the People's Republic of China.
Int J Chron Obstruct Pulmon Dis
PUBLISHED: 01-01-2014
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Chronic obstructive pulmonary disease (COPD) is a common disease that severely threatens human health. Acute exacerbation of COPD (AECOPD) is a major cause of disease progression and death, and causes huge medical expenditures. This consensus statement represents a description of clinical features of AECOPD in the People's Republic of China and a set of recommendations. It is intended to provide clinical guidelines for community physicians, pulmonologists and other health care providers for the prevention, diagnosis, and treatment of AECOPD.
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High-resolution functional annotation of human transcriptome: predicting isoform functions by a novel multiple instance-based label propagation method.
Nucleic Acids Res.
PUBLISHED: 12-25-2013
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Alternative transcript processing is an important mechanism for generating functional diversity in genes. However, little is known about the precise functions of individual isoforms. In fact, proteins (translated from transcript isoforms), not genes, are the function carriers. By integrating multiple human RNA-seq data sets, we carried out the first systematic prediction of isoform functions, enabling high-resolution functional annotation of human transcriptome. Unlike gene function prediction, isoform function prediction faces a unique challenge: the lack of the training data-all known functional annotations are at the gene level. To address this challenge, we modelled the gene-isoform relationships as multiple instance data and developed a novel label propagation method to predict functions. Our method achieved an average area under the receiver operating characteristic curve of 0.67 and assigned functions to 15 572 isoforms. Interestingly, we observed that different functions have different sensitivities to alternative isoform processing, and that the function diversity of isoforms from the same gene is positively correlated with their tissue expression diversity. Finally, we surveyed the literature to validate our predictions for a number of apoptotic genes. Strikingly, for the famous TP53 gene, we not only accurately identified the apoptosis regulation function of its five isoforms, but also correctly predicted the precise direction of the regulation.
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[Fractal characteristics of capillary finger flow for NAPLs infiltrated in porous media].
Huan Jing Ke Xue
PUBLISHED: 12-25-2013
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Non-aqueous phase liquids (NAPLs) like petroleum hydrocarbons and chlorinated solvents have resulted in contamination of soils and ground water, which aroused widespread concern. Its quite important to delineate pollution area for remediation according to different soil types with pollutants properties in consideration. In this paper, a two-dimension visual sand box apparatus was constructed, with four typical NAPLs selected for infiltration experiments conducted in initially dry porous media. The main driving force was identified and fingering patterns were compared. The fractal dimension was used to give quantitative description. The present work indicates that the main driving force was capillary forces and the mechanism was the capillary fingering. The fingers varied from skeletal patterns to fleshy patterns and the infiltration area increased when the capillary number and the bond number decreased for NAPLs with the same level of viscosity. The high viscous force resulted in larger finger width and infiltration area. The same change between fluids happened in finer media. Fractal dimensions were positively correlated with the finger width and infiltration area, which is helpful in the pollution area characterization.
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Multiple Rice miRNAs Are Involved in Immunity against the Blast Fungus Magnaporthe oryzae.
Plant Physiol.
PUBLISHED: 12-13-2013
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MicroRNAs (miRNAs) are indispensable regulators for development and defense in eukaryotes. However, the miRNA species have not been explored for rice immunity against the blast fungus Magnaporthe oryzae, the most devastating fungal pathogen in rice production worldwide. Here, by deep sequencing small RNA (sRNA) libraries from susceptible and resistant lines at normal conditions and upon M. orzyzae infection, we identified a group of known rice miRNAs that were differentially expressed upon M. oryzae infection. They were further classified into three classes based on their expression patterns in the susceptible line LTH (Lijiangxin Tuan Hegu, Oryza sativa L. japonica) and in the resistant line IRBLkm-Ts that contains a single resistance gene locus Pikm within LTH background. RNA-blotting assay on nine of them confirmed sequencing results. Real-time reverse transcription (RT) PCR assay showed the expressions of a part of target genes were negatively correlated with the expressions of miRNAs. Moreover, transgenic rice plants over-expressing miR160a and miR398b displayed enhanced resistance to M. oryzae as demonstrated by decreased fungal growth, increased H2O2 accumulation at the infection site and up-regulated expression of defense-related genes. Taken together, our data indicate that miRNAs are involved in rice immunity against M. oryzae and over-expression of miR160a or miR398b can enhance rice resistance to the disease.
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Crystal Structure of the Interferon Gamma Receptor Alpha Chain from Chicken Reveals an Undetected Extra Helix Compared with the Human Counterparts.
J. Interferon Cytokine Res.
PUBLISHED: 11-27-2013
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Interferon gamma (IFN-?) is an important cytokine that induces antiviral, antiproliferative, and immunomodulatory effects on target cells, and is also crucial in the early defense against intracellular parasites, such as Listeria monocytogenes and Toxoplasma gondii. The biological activity of IFN-? relies upon the formation of a complex with its 2 receptors, the interferon gamma alpha chain (IFNGR1) and beta chain (IFNGR2), which are type II cytokine receptors. Structural models of ligand-receptor interaction and complex structure of chicken IFNs with their receptors have remained elusive. Here we report the first structure of Gallus gallus (chicken) IFNGR1 (chIFNGR1) at 2.0 Å by molecule replacement according to the structure of selenomethionine substituted chIFNGR1. The structural comparison reveals its structural similarities with other class II cytokine receptors, despite divergent primary sequences. We further investigate the ligand-receptor interaction properties of chicken IFN-? (chIFN-?) and chIFNGR1 using size-exclusion chromatography and surface plasmon resonance techniques. These data aid in the understanding of the interaction of chicken (avian) IFN-? with its receptors and its signal transduction.
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Mitogen-activated protein kinase-activated protein kinase 2 regulates tumor necrosis factor-induced interleukin-6 expression via human antigen R.
Chin. Med. J.
PUBLISHED: 11-19-2013
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Human antigen R (HuR) is a ubiquitously expressed member of the ELAV family, and has relatively high cytoplasmic abundance in lung tissue regenerating after injury. In this study, we investigated whether mitogen-activated protein kinase (MAPK)-activated protein kinase 2 (MK2) and HuR participate in the tumor necrosis factor (TNF)-induced expression of interleukin-6 (IL-6).
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Intramolecular Transannulation of Alkynyl Triazoles via Alkyne-Carbene Metathesis Step: Access to Fused Pyrroles.
Org. Lett.
PUBLISHED: 10-04-2013
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An intramolecular Rh-catalyzed transannulation reaction of alkynyl triazoles has been developed. This method allows efficient construction of various 5,5-fused pyrroles, including tetrahydropyrrolo and spiro systems. The method demonstrates excellent functional group compatibility. A rhodium carbene-alkyne metathesis mechanism is proposed for this transformation.
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Hollow structured Li3VO4 wrapped with graphene nanosheets in situ prepared by a one-pot template-free method as an anode for lithium-ion batteries.
Nano Lett.
PUBLISHED: 09-20-2013
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To explore good anode materials of high safety, high reversible capacity, good cycling, and excellent rate capability, a Li3VO4 microbox with wall thickness of 40 nm was prepared by a one-pot and template-free in situ hydrothermal method. In addition, its composite with graphene nanosheets of about six layers of graphene was achieved. Both of them, especially the Li3VO4/graphene nanosheets composite, show superior electrochemical performance to the formerly reported vanadium-based anode materials. The composite shows a reversible capacity of 223 mAh g(-1) even at 20C (1C = 400 mAh g(-1)). After 500 cycles at 10C there is no evident capacity fading.
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Memory and learning behaviors mimicked in nanogranular SiO2-based proton conductor gated oxide-based synaptic transistors.
Nanoscale
PUBLISHED: 09-17-2013
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In neuroscience, signal processing, memory and learning function are established in the brain by modifying ionic fluxes in neurons and synapses. Emulation of memory and learning behaviors of biological systems by nanoscale ionic/electronic devices is highly desirable for building neuromorphic systems or even artificial neural networks. Here, novel artificial synapses based on junctionless oxide-based protonic/electronic hybrid transistors gated by nanogranular phosphorus-doped SiO2-based proton-conducting films are fabricated on glass substrates by a room-temperature process. Short-term memory (STM) and long-term memory (LTM) are mimicked by tuning the pulse gate voltage amplitude. The LTM process in such an artificial synapse is due to the proton-related interfacial electrochemical reaction. Our results are highly desirable for building future neuromorphic systems or even artificial networks via electronic elements.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.