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Find video protocols related to scientific articles indexed in Pubmed.
Endovascular embolization for managing anastomotic bleeding after stapled digestive tract anastomosis.
Acta Radiol
PUBLISHED: 11-20-2014
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Anastomotic bleeding is an infrequent but life-threatening complication after stapled digestive tract anastomosis. Endovascular embolization is one of the available treatments, but precise clinical outcomes are yet to be evaluated.
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Substituent Electronic Effects Govern Direct Intramolecular C-N Cyclization of N-(Biphenyl)pyridin-2-amines Induced by Hypervalent Iodine(III) Reagents.
J. Org. Chem.
PUBLISHED: 11-05-2014
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The hypervalent iodine(III) reagent-induced the direct intramolecular C-N cyclization of N-(biphenyl)pyridin-2-amines to 6-arylbenzimidazoles and N-pyridinyl-9H-carbazoles is presented. The substituent electronic effects governing the formation of benzimidazoles and carbazoles from the reaction of N-(biphenyl)pyridin-2-amines with hypervalent iodine(III) reagents is investigated. Radical trapping and UV-vis spectroscopic experiments on the detection of the cation radical are carried out. Rational mechanisms for these reactions are presented. The selective intramolecular C-N and C-O cyclization of N-(biphenyl)acetamides based on the substituent electronic effects is also presented.
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Serum YKL-40 is increased in patients with slow coronary flow.
Coron. Artery Dis.
PUBLISHED: 10-31-2014
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There is accumulating evidence that inflammation plays a major role in the development of the slow coronary flow (SCF) phenomenon. YKL-40 has been suggested to be a potential biomarker of inflammation. In this study, we aimed to study YKL-40 as it relates to SCF.
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One-step pyrolytic synthesis of nitrogen and sulfur dual-doped porous carbon with high catalytic activity and good accessibility to small biomolecules.
ACS Appl Mater Interfaces
PUBLISHED: 10-28-2014
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As one of promising catalysts that contain high density of active sites, N doped carbons have been extensively researched, while the reports for N, S dual-doped carbon materials are far less exhaustive. Herein, devoid of activation process and template, N, S dual-doped porous carbon (N-S-PC) was prepared for the first time via one-step pyrolysis of sodium citrate and cysteine. Possessing unique porous structure and large pore volume as well as good accessibility, N-S-PC demonstrates significantly improved electrocatalytic activity toward oxidation of ascorbic acid (AA), dopamine (DA), and uric acid (UA). In the coexisting system, the peak potential separation between AA and DA is up to 251 mV, which is much larger than for most of the other carbons. On the basis of large potential separation and high current response, selective and sensitive simultaneous determination of AA, DA, and UA was successfully accomplished by differential pulse voltammetry, displaying a linear response from 50 to 2000 ?M, from 0.1 to 50 ?M, and from 0.1 to 50 ?M with a detection limit (S/N = 3) of 0.78, 0.02, and 0.06 ?M. This work highlights the importance of N, S dual doping and hierarchical porous carbons for efficient catalysis.
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[Percutaneous vertebroplasty for treatment of painful osteoporotic vertebral compression fractures: a retrospective analysis of clinical efficacy].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 10-21-2014
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To evaluate the clinical efficacy and radiological changes in patients with painful osteoporotic vertebral compression fractures (OVCFs) after percutaneous vertebroplasty (PVP).
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Identifying progression related disease risk modules based on the human subcellular signaling networks.
Mol Biosyst
PUBLISHED: 10-16-2014
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Many studies have shown that the structure and dynamics of the human signaling network are disturbed in complex diseases such as coronary artery disease, and gene expression profiles can distinguish variations in diseases since they can accurately reflect the status of cells. Integration of subcellular localization and the human signaling network holds promise for providing insight into human diseases. In this study, we performed a novel algorithm to identify progression-related-disease-risk modules (PRDRMs) among patients of different disease states within eleven subcellular sub-networks from a human signaling network. The functional annotation and literature retrieval showed that the PRDRMs were strongly associated with disease pathogenesis. The results indicated that the PRDRM expression values as classification features had a good classification performance to distinguish patients of different disease states. Our approach compared with the method PageRank had a better classification performance. The identification of the PRDRMs in response to the dynamic gene expression change could facilitate our understanding of the pathological basis of complex diseases. Our strategy could provide new insights into the potential use of prognostic biomarkers and the effective guidance of clinical therapy from the human subcellular signaling network perspective.
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Nitrogen-rich graphene from small molecules as high performance anode material.
Nanotechnology
PUBLISHED: 09-27-2014
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Nitrogen-rich graphene sheets were successfully achieved via facile thermal condensation of glucose and dicyandiamide at different temperatures during which dicyandiamide acts both as nitrogen source and sacrifice template. Devoid of surfactants or poisonous organic solvents, this small-molecule synthetic approach is a simple and cost-effective way to obtain nitrogen-rich graphene sheets (NRGS) with high specific surface area and large pore volume. Shown to be a promising anode material, the NRGS displayed high reversible capacity, excellent rate capability, and superior cycle performance. The superior lithium-storage performance is ascribed to the unique features of NRGS, including a large quantity of defects due to the high nitrogen doping level, favorable lithium ion transportation channels by virtue of the large surface area, and ultrahigh pore volume, as well as the crumpled two-dimensional structure.
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cDNA-AFLP analysis reveals the adaptive responses of citrus to long-term boron-toxicity.
BMC Plant Biol.
PUBLISHED: 09-13-2014
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BackgroundBoron (B)-toxicity is an important disorder in agricultural regions across the world. Seedlings of `Sour pummelo¿ (Citrus grandis) and `Xuegan¿ (Citrus sinensis) were fertigated every other day until drip with 10 ¿M (control) or 400 ¿M (B-toxic) H3BO3 in a complete nutrient solution for 15 weeks. The aims of this study were to elucidate the adaptive mechanisms of citrus plants to B-toxicity and to identify B-tolerant genes.ResultsB-toxicity-induced changes in seedlings growth, leaf CO2 assimilation, pigments, total soluble protein, malondialdehyde (MDA) and phosphorus were less pronounced in C. sinensis than in C. grandis. B concentration was higher in B-toxic C. sinensis leaves than in B-toxic C. grandis ones. Here we successfully used cDNA-AFLP to isolate 67 up-regulated and 65 down-regulated transcript-derived fragments (TDFs) from B-toxic C. grandis leaves, whilst only 31 up-regulated and 37 down-regulated TDFs from B-toxic C. sinensis ones, demonstrating that gene expression is less affected in B-toxic C. sinensis leaves than in B-toxic C. grandis ones. These differentially expressed TDFs were related to signal transduction, carbohydrate and energy metabolism, nucleic acid metabolism, protein and amino acid metabolism, lipid metabolism, cell wall and cytoskeleton modification, stress responses and cell transport. The higher B-tolerance of C. sinensis might be related to the findings that B-toxic C. sinensis leaves had higher expression levels of genes involved in photosynthesis, which might contribute to the higher photosyntheis and light utilization and less excess light energy, and in reactive oxygen species (ROS) scavenging compared to B-toxic C. grandis leaves, thus preventing them from photo-oxidative damage. In addition, B-toxicity-induced alteration in the expression levels of genes encoding inorganic pyrophosphatase 1, AT4G01850 and methionine synthase differed between the two species, which might play a role in the B-tolerance of C. sinensis.Conclusions C. sinensis leaves could tolerate higher level of B than C. grandis ones, thus improving the B-tolerance of C. sinensis plants. Our findings reveal some novel mechanisms on the tolerance of plants to B-toxicity at the gene expression level.
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5,7,3',4'-Tetramethoxyflavone exhibits chondroprotective activity by targeting ?-catenin signaling in vivo and in vitro.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-01-2014
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Osteoarthritis (OA) is a progressive joint disorder, which remains the leading cause of chronic disability in aged people. This study is the first report which demonstrates the cartilage protective effect of 5,7,3',4'-tetramethoxyflavone (TMF) by decreasing the concentration of IL-1?, TNF-? and PGE2 in the knee synovial fluid in OA rat models in vivo. In vitro, after induced by PGE2, the apoptosis rate of chondrocytes was significantly increased. In addition, PGE2 increased the expression of cAMP/PKA signaling pathway in chondrocytes, stabilized and accumulated ?-catenin, and activated the expression of ?-catenin signaling pathway. These activities were counteracted by TMF dose-dependently. Collectively, TMF is a potential compound with chondroprotective activity by inhibiting both EP/cAMP/PKA signaling pathway and ?-catenin signaling pathway.
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[MrgC receptor activation reverses chronic morphine-evoked alterations of glutamate transporters and nNOS in rats].
Sheng Li Xue Bao
PUBLISHED: 08-19-2014
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This study was aimed to investigate the mechanisms underlying the modulation effect of Mas-related gene (Mrg) C receptors (MrgC) on morphine tolerance. Saline, morphine (20 ?g), morphine plus bovine adrenal medulla 8-22 (BAM8-22, 1 nmol) or (Tyr(6))-2-MSH-6-12 (MSH, 5 nmol) were administered intrathecally in rats for 6 days. Pain-related molecules in the spinal cord and dorsal root ganglion (DRG) were examined using Western blot, immunocytochemistry and RT-PCR techniques. The results showed that intrathecal administration of the selective MrgC receptor agonists (BAM8-22 or MSH) remarkably attenuated or abolished chronic morphine-evoked reduction in glutamate transporters (GLAST, GLT-1 and EAAC1) in the spinal cord and increase in neuronal nitric oxide synthase (nNOS) in the spinal cord as well as DRG. In addition, MrgC receptor-like immunoreactivity (IR) was detected in superficial laminae of the spinal cord. Chronic morphine induced significant increases in MrgC receptor-IR in the spinal cord and MrgC receptor mRNA levels in DRG. These results suggest that the modulation of pro-nociceptive mediators in the spinal cord and DRG underlies the inhibition of morphine tolerance by MrgC receptor activation.
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Increased dissolution of disulfiram by dry milling with silica nanoparticles.
Drug Dev Ind Pharm
PUBLISHED: 08-18-2014
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Abstract The purpose of this study was to find a suitable method to increase the dissolution of disulfiram (DSF) which is easily decomposed. The dissolution of DSF within 1?h was significantly increased from 37% to >90% by co-milling with Aerosil® 200 pharm (Aerosil) and the increased dissolution remained stable during long-term storage while there was no significant degradation of DSF. By monitoring the changes in particle size of the grinding mixture, a mosaic DSF-in-Aerosil structure was demonstrated. The core size of the mosaic DSF/Aerosil system was 3.625?µm. The particle size of DSF was reduced from 20.75?µm to ?200?nm and the size of the mosaic DSF/Aerosil system (3.625?7.956?µm) increased on increasing the drug-loading content. Differential scanning calorimetry and X-ray powder diffraction analysis confirmed the largely amorphous state of DSF in the mosaic drug/carrier system. Fourier transform infrared spectroscopy confirmed the presence of hydrogen bonding between DSF and Aerosil. Scanning electron microscopy and transmission electron microscopy verified the DSF-in-Aerosil relationship in the particle size determination at different size levels. The possible mechanisms of dry milling included the hypothesis that during impact and collision, DSF particles melted into the surface of Aerosil turning them into an amorphous state or they became inlayed into the interspaces of the Aerosil structure with a much smaller size.
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High NR2F2 transcript level is associated with increased survival and its expression inhibits TGF-?-dependent epithelial-mesenchymal transition in breast cancer.
Breast Cancer Res. Treat.
PUBLISHED: 08-17-2014
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NR2F2, a member of nuclear receptor subfamily 2, was shown to be associated with cancer, but its role in breast malignancy remains unclear. In this study, we aimed to explore the function of NR2F2 in breast cancer. We browsed GEO and TCGA databases and used Kaplan-Meier survival analysis to explore the association between NR2F2 transcript level and patient survival in breast cancer. NR2F2 expression in breast cancer tissues was evaluated by immunohistochemistry staining. NR2F2-related functions and its role in Epithelial-Mesenchymal Transition (EMT) were predicted by Gene Set Enrichment Analysis (GSEA) and validated by in vitro assays with NR2F2 knockdown MDA-MB231 and MCF7 cells. We found high NR2F2 transcript level was correlated with favorable overall survival and distant metastasis-free survival. Positive rate of NR2F2 protein tended to be decreased with the progression of malignancy. Results of in vitro migration and invasion assays suggested NR2F2's potential in inhibiting invasiveness. NR2F2 was predicted to be negatively linked with EMT and TGF-?-pathway related genes, which was supported by observation of EMT-like morphology and changes in EMT-markers E-cadherin and Slug. Additionally, we found TGF-? inhibited the expression of NR2F2. GSEA also predicted that NR2F2 could be inversely associated with chemoresistance, which was verified by results of in vitro growth inhibition assays using chemotherapeutic agents. Our results demonstrated high NR2F2 transcript level was associated with favorable clinical outcome, which might be due to NR2F2's inhibitory effect on TGF-?-dependent EMT and its role in inhibiting chemoresistance.
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Plasmon-induced broadband fluorescence enhancement on Al-Ag bimetallic substrates.
Sci Rep
PUBLISHED: 08-11-2014
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Surface enhanced fluorescence (SEF) utilizes the local electromagnetic environment to enhance fluorescence from the analyte on the surface of a solid substrate with nanostructures. While the detection sensitivity of SEF is improved with the development of nano-techniques, detection of multiple analytes by SEF is still a challenge due to the compromise between the high enhancing efficiency and broad response bandwidth. In this article, a high-efficiency SEF substrate with broad response bandwidth is obtained by embedding silver in an aluminum film to produce additional bonding and anti-bonding hybridized states. The bimetallic film is fabricated by ion implantation and the ion energy and fluence are tailored to control subsurface location of the fabricated bimetallic nanostructures. The process circumvents the inherent limit of aluminum materials and extends the plasmon band of aluminum from deep UV to visible range. Fluorescence from different dyes excited by 310 nm to 555 nm is enhanced by up to 11 folds on the single bimetallic film and the result is theoretically confirmed by finite-difference time-domain simulations. This work demonstrates that bimetallic film can be used for optical detection of multiple analytes.
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Crosstalk mitigation in a free-space orbital angular momentum multiplexed communication link using 4×4 MIMO equalization.
Opt Lett
PUBLISHED: 08-01-2014
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We demonstrate crosstalk mitigation using 4×4 multiple-input-multiple-output (MIMO) equalization on an orbital angular momentum (OAM) multiplexed free-space data link with heterodyne detection. Four multiplexed OAM beams, each carrying a 20??Gbit/s quadrature phase-shift keying signal, propagate through weak turbulence. The turbulence induces inter-channel crosstalk among each beam and degrades the signal performance. Experimental results demonstrate that with the assistance of MIMO processing, the signal quality and the bit-error-rate (BER) performance can be improved. The power penalty can be reduced by >4??dB at a BER of 3.8×10-3.
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Characterization of the enterovirus 71 P1 polyprotein expressed in Pichia pastor is as a candidate vaccine.
Hum Vaccin Immunother
PUBLISHED: 07-23-2014
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Human enterovirus 71 (EV71) plays an important role in hand, foot, and mouth disease (HFMD), which recently caused the death of hundreds of children in the Asia-Pacific region. However, there are no specific treatments available for EV71 infections; thus, a safe and effective vaccine is needed urgently. In this study, we developed an effective and economical method for producing EV71 polyprotein (P1 protein) in Pichia pastoris. Furthermore, we evaluated the potential of P1 protein as a candidate vaccine against EV71 virus. The data revealed that P1 protein induced persistent high cross-neutralization antibodies for different EV71 subtypes, and elicited significant splenocyte proliferation. The high levels of interleukin-10(IL-10) and interferon-gamma (IFN-?) showed that P1 protein induced Th1 and Th2 immune responses. Interestingly, vaccinating female mice with the P1 protein conferred cross-protection against different EV71 subtypes to their neonatal offspring.Compared with heat-inactivated EV71, the P1 protein elicited improved humoral and cellular immune responses and showed good cross-protection with different EV71 subtypes. Therefore, the EV71-P1 protein produced by P. pastoris is a promising candidate vaccine against EV71.
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[Effects of electroacupuncture at "Fenglong" (ST 40) on formation of macrophage-derived foam cell and efflux of cholesterol in hyperlipidemia rats].
Zhongguo Zhen Jiu
PUBLISHED: 07-16-2014
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To explore action mechanism of electroacupuncture (EA) at "Fenglong" (ST 40) for treatment of hyperlipidemia.
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Letrozole versus clomiphene for infertility in the polycystic ovary syndrome.
N. Engl. J. Med.
PUBLISHED: 07-10-2014
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Clomiphene is the current first-line infertility treatment in women with the polycystic ovary syndrome, but aromatase inhibitors, including letrozole, might result in better pregnancy outcomes.
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Can Modulating Inflammatory Response Be a Good Strategy to Treat Neuropathic Pain?
Curr. Pharm. Des.
PUBLISHED: 07-09-2014
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Neuronal injury not only results in severe alteration in the function of primary sensory neurons and their central projection pathway, but is also associated with a robust immune response at almost every level of the somatosensory system. Studies in animal studies suggest undoubtedly that bi-directional signalling between the immune system and the nervous system contribute to the development and maintenance of chronic neuropathic pain. Non-neuronal cells, including peripheral immune cells, CNS/PNS glial cells and endothelial cells play important roles in the neuroimmune interaction and subsequent persistent hypersensitivity. Various cytokines and chemokines have been identified as key signalling molecules in the crosstalk. However, majority evidence showing inflammation in neuropathic pain was generated from animal models at acute phase. Whether and to what extent inflammation or non-neuronal cells are involved at chronic stage of neuropathic pain needs to be further explored, and evidence of inflammation in chronic pain from human studies is still largely awaited. Therapeutic agents targeting inflammation provide an exciting prospect. Yet, considering the heterogeneous conditions presented in neuropathic pain, no matter the etiologies, or the pathophysiology during different stages of the disease; and the complexity of the immune response to the damage on the nervous system, it appears that finely tuned strategies of modulating inflammation are essential to warrant an effective treatment for neuropathic pain. We want to reduce pain; we also want to promote tissue repair and functional recovery.
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Adaptive optics compensation of multiple orbital angular momentum beams propagating through emulated atmospheric turbulence.
Opt Lett
PUBLISHED: 07-01-2014
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We propose an adaptive optics compensation scheme to simultaneously compensate multiple orbital angular momentum (OAM) beams propagating through atmospheric turbulence. A Gaussian beam on one polarization is used to probe the turbulence-induced wavefront distortions and derive the correction pattern for compensating the OAM beams on the orthogonal polarization. By using this scheme, we experimentally demonstrate simultaneous compensation of multiple OAM beams, each carrying a 100??Gbit/s data channel through emulated atmospheric turbulence. The experimental results indicate that the correction pattern obtained from the Gaussian probe beam could be used to simultaneously compensate multiple turbulence-distorted OAM beams with different orders. It is found that the turbulence-induced crosstalk effects on neighboring modes are efficiently reduced by 12.5 dB, and the system power penalty is improved by 11 dB after compensation.
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Stage-specific regulation of oligodendrocyte development by Wnt/?-catenin signaling.
J. Neurosci.
PUBLISHED: 06-21-2014
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Oligodendrocytes are myelin-forming glia that ensheath the axons of neurons in the CNS. Recent studies have revealed that Wnt/?-catenin signaling plays important roles in oligodendrocyte development and myelin formation. However, there are conflicting reports on the specific function of Wnt signaling components in oligodendrocyte specification and differentiation. In the present study, we demonstrate that activation of ?-catenin in neural progenitor cells before gliogenesis inhibits the generation of oligodendrocyte progenitors (OLPs) in mice. Once OLPs are formed, ?-catenin becomes necessary for oligodendrocyte differentiation. Disruption of ?-catenin signaling instead leads to a significant delay of oligodendrocyte maturation. These findings suggest that Wnt/?-catenin pathway regulates oligodendrocyte development in a stage-dependent manner.
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Estimating parameters and predicting membrane voltages with conductance-based neuron models.
Biol Cybern
PUBLISHED: 06-09-2014
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Recent results demonstrate techniques for fully quantitative, statistical inference of the dynamics of individual neurons under the Hodgkin-Huxley framework of voltage-gated conductances. Using a variational approximation, this approach has been successfully applied to simulated data from model neurons. Here, we use this method to analyze a population of real neurons recorded in a slice preparation of the zebra finch forebrain nucleus HVC. Our results demonstrate that using only 1,500 ms of voltage recorded while injecting a complex current waveform, we can estimate the values of 12 state variables and 72 parameters in a dynamical model, such that the model accurately predicts the responses of the neuron to novel injected currents. A less complex model produced consistently worse predictions, indicating that the additional currents contribute significantly to the dynamics of these neurons. Preliminary results indicate some differences in the channel complement of the models for different classes of HVC neurons, which accords with expectations from the biology. Whereas the model for each cell is incomplete (representing only the somatic compartment, and likely to be missing classes of channels that the real neurons possess), our approach opens the possibility to investigate in modeling the plausibility of additional classes of channels the cell might possess, thus improving the models over time. These results provide an important foundational basis for building biologically realistic network models, such as the one in HVC that contributes to the process of song production and developmental vocal learning in songbirds.
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The influence of monoamine oxidase variants on the risk of betel quid-associated oral and pharyngeal cancer.
ScientificWorldJournal
PUBLISHED: 06-05-2014
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Betel quid (BQ) and areca nut (AN) (major BQ ingredient) are group I human carcinogens illustrated by International Agency for Research on Cancer and are closely associated with an elevated risk of oral potentially malignant disorders (OPMDs) and cancers of the oral cavity and pharynx. The primary alkaloid of AN, arecoline, can be metabolized via the monoamine oxidase (MAO) gene by inducing reactive oxygen species (ROS). The aim of this study was to investigate whether the variants of the susceptible candidate MAO genes are associated with OPMDs and oral and pharyngeal cancer. A significant trend of MAO-A mRNA expression was found in in vitro studies. Using paired human tissues, we confirmed the significantly decreased expression of MAO-A and MAO-B in cancerous tissues when compared with adjacent noncancerous tissues. Moreover, we determined that MAO-A single nucleotide polymorphism variants are significantly linked with oral and pharyngeal cancer patients in comparison to OPMDs patients [rs5953210 risk G-allele, odds ratio = 1.76; 95% confidence interval = 1.02-3.01]. In conclusion, we suggested that susceptible MAO family variants associated with oral and pharyngeal cancer may be implicated in the modulation of MAO gene activity associated with ROS.
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A G-quadruplex-containing RNA activates fluorescence in a GFP-like fluorophore.
Nat. Chem. Biol.
PUBLISHED: 05-21-2014
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Spinach is an in vitro-selected RNA aptamer that binds a GFP-like ligand and activates its green fluorescence. Spinach is thus an RNA analog of GFP and has potentially widespread applications for in vivo labeling and imaging. We used antibody-assisted crystallography to determine the structures of Spinach both with and without bound fluorophore at 2.2-Å and 2.4-Å resolution, respectively. Spinach RNA has an elongated structure containing two helical domains separated by an internal bulge that folds into a G-quadruplex motif of unusual topology. The G-quadruplex motif and adjacent nucleotides comprise a partially preformed binding site for the fluorophore. The fluorophore binds in a planar conformation and makes extensive aromatic stacking and hydrogen bond interactions with the RNA. Our findings provide a foundation for structure-based engineering of new fluorophore-binding RNA aptamers.
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Synthesis and electrochemical properties of silicon nanosheets by DC arc discharge for lithium-ion batteries.
Nanoscale
PUBLISHED: 05-17-2014
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Two-dimensional (2D) ultrathin silicon nanosheets (Si NSs) were synthesized by DC arc discharge method and investigated as anode material for Li-ion batteries. The 2D ultrathin characteristics of Si NSs is confirmed by means of transmission electron microscopy (TEM) and atomic force microscopy (AFM). The average size of Si NSs is about 20 nm, with thickness less than 2.5 nm. The characteristic Raman peak of Si NSs is found to have an appreciable (20 nm) shift to low frequency, presumably due to the size effect. The synergistic effects of Ar(+) and H(+) lead to 2D growth of Si NSs under high temperature and energy. Electrochemical analyses reveal that Si NSs anode possesses stable cycling performance and fast diffusion of Li-ions with insertion/extraction processes. Such Si NSs might be a promising candidate for anode of Li-ion batteries.
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[Platelet derived growth factor receptor ? over-expression in endothelial progenitor cells promote reendothelialization after vascular injury].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 05-17-2014
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To observe the effect of platelet derived growth factor receptor ? (PDGFR-?) transfected endothelial progenitor cells (EPCs) on vascular regeneration.
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[Establishment of drug resistant cell line of MGC-803 and analysis of differential secretome].
Beijing Da Xue Xue Bao
PUBLISHED: 04-19-2014
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To identify chemoresistance-associated secretory proteins by proteomic approaches, and to provide the basis for selecting suitable chemotherapy in gastric cancer treatment.
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Label-free detection of blood plasma using silver nanoparticle based surface-enhanced Raman spectroscopy for esophageal cancer screening.
J Biomed Nanotechnol
PUBLISHED: 04-16-2014
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A surface-enhanced Raman spectroscopy (SERS) based on silver nanoparticle technology was applied to analyze and classify human blood plasma with the aim to develop a simple and label-free blood test for esophageal cancer detection. High quality SERS spectra in the range of 400-1800 cm(-1) can be acquired from 36 esophageal cancer patients and 50 healthy volunteers' blood plasma samples. Tentative assignments of the SERS bands indicated specific biomolecular changes associated with cancer transformation, including an increase in the relative amounts of nucleic acid and phenylalanine, a decrease in the percentage of saccharide and proteins contents in the cancer blood plasma compared to that of healthy subjects. Furthermore, both SVM and PCA-LDA diagnostic algorithm were employed to analyze and classify the obtained blood plasma SERS spectra between normal and cancer plasma with a high diagnostic accuracy (around 90%). This exploratory work demonstrates that the label-free plasma SERS analysis technique in conjunction with SVM and PCA-LDA diagnostic algorithms has great potential for improving esophageal cancer detection and screening.
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[Risk evaluation of schistosomiasis japonica input to potential endemic areas in Anhui province].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 04-10-2014
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To analyze the impact of water transfer project from the Yangtze River to the Huaihe River on schistisomiasis transmission, and to evaluate the risk of the disease input to the potential endemic area in Anhui Province, namely the Chaohu Lake region.
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Label-free blood plasma test based on surface-enhanced Raman scattering for tumor stages detection in nasopharyngeal cancer.
Sci Rep
PUBLISHED: 04-04-2014
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This study aims to evaluate the feasibility of a label-free nanobiosensor based on blood plasma surface-enhanced Raman spectroscopy (SERS) method for exploring variability of different tumor (T) stages in nasopharyngeal cancer (NPC). Au nanoparticles as the SERS-active nanostructures were directly mixed with human blood plasma to enhance the Raman scattering signals. High quality SERS spectra can be acquired from blood plasma samples belong to 60 healthy volunteers, 25 NPC patients with T1 stage and 75 NPC patients with T2-T4 stage. A diagnostic accuracy of 83.5% and 93.3%, respectively, can be achieved for classification between early T (T1) stage cancer and normal; and advanced T (T2-T4) stage cancer and normal blood groups. This exploratory study demonstrates that the nanobiosensor based on SERS technique in conjunction with PCA-LDA has great potential as a clinical complement for different T stages detection in nasopharyngeal cancer.
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Tunable orbital angular momentum mode filter based on optical geometric transformation.
Opt Lett
PUBLISHED: 04-03-2014
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We present a tunable mode filter for spatially multiplexed laser beams carrying orbital angular momentum (OAM). The filter comprises an optical geometric transformation-based OAM mode sorter and a spatial light modulator (SLM). The programmable SLM can selectively control the passing/blocking of each input OAM beam. We experimentally demonstrate tunable filtering of one or multiple OAM modes from four multiplexed input OAM modes with vortex charge of ?=-9, -4, +4, and +9. The measured output power suppression ratio of the propagated modes to the blocked modes exceeds 14.5 dB.
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Competitive Reaction Pathway for Site-Selective Conjugation of Raman Dyes to Hotspots on Gold Nanorods for Greatly Enhanced SERS Performance.
Small
PUBLISHED: 03-29-2014
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Common methods to prepare SERS (surface-enhanced Raman scattering) probes rely on random conjugation of Raman dyes onto metal nanostructures, but most of the Raman dyes are not located at Raman-intense electromagnetic hotspots thus not contributing to SERS enhancement substantially. Herein, a competitive reaction between transverse gold overgrowth and dye conjugation is described to achieve site selective conjugation of Raman dyes to the hotspots (ends) on gold nanorods (GNRs). The preferential overgrowth on the nanorod side surface creates a barrier to prevent the Raman dyes from binding to the side surface except the ends of the GNRs, where the highest SERS enhancement factors are expected. The SERS enhancement observed from this special structure is dozens of times larger than that from conjugates synthesized by conventional methods. This simple and powerful strategy to prepare SERS probes can be extended to different anisotropic metal nanostructures with electromagnetic hotspots and has immense potential in in-depth SERS-based biological imaging and single-molecule detection.
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High-capacity millimetre-wave communications with orbital angular momentum multiplexing.
Nat Commun
PUBLISHED: 03-17-2014
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One property of electromagnetic waves that has been recently explored is the ability to multiplex multiple beams, such that each beam has a unique helical phase front. The amount of phase front 'twisting' indicates the orbital angular momentum state number, and beams with different orbital angular momentum are orthogonal. Such orbital angular momentum based multiplexing can potentially increase the system capacity and spectral efficiency of millimetre-wave wireless communication links with a single aperture pair by transmitting multiple coaxial data streams. Here we demonstrate a 32-Gbit s(-1) millimetre-wave link over 2.5 metres with a spectral efficiency of ~16 bit s(-1) Hz(-1) using four independent orbital-angular momentum beams on each of two polarizations. All eight orbital angular momentum channels are recovered with bit-error rates below 3.8 × 10(-3). In addition, we demonstrate a millimetre-wave orbital angular momentum mode demultiplexer to demultiplex four orbital angular momentum channels with crosstalk less than -12.5 dB and show an 8-Gbit s(-1) link containing two orbital angular momentum beams on each of two polarizations.
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Mitochondrial pathology in osteoarthritic chondrocytes.
Curr Drug Targets
PUBLISHED: 03-02-2014
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Osteoarthritis (OA) is a chronic degenerative disease leading to aberrance of cartilage structures with unclear or multifactorial mechanisms. Recently, a great portion of research endeavor to explore the molecular mechanisms of OA in focusing on the mitochondrial pathology. Mitochondrial respiratory chain (MRC) produces reactive oxygen species (ROS), which in turn impair mtDNA integrity and link to cartilage degradation in OA. The fine-tuning between ROS and antioxidant within chondrocytes ensures cartilage homeostasis. With disturbance from pro-inflammatory cytokines, oxidative stress synergistically instigates cellular signaling and exacerbates mitochondrial pathology, which may affect several pathways implicated in OA cartilage degradation, including oxidative stress, increase of cytokine-induced chondrocytes inflammation and matrix catabolism, aging and senescence, obesity-related pathology, and cartilage matrix calcification. Unveiling the molecular mechanisms of mitochondrial function in OA pathogenesis and progression is essential for providing relevant therapeutic targets. These suggest that efficient protection and improvement of mitochondrial activity can be a therapeutic alternative for OA patients.
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Analysis on micro-regional characters of the resistance wires surface in electrical immersion heater by SEM/EDX.
Forensic Sci. Int.
PUBLISHED: 03-02-2014
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We present a novel method for identifying the conditions of electrical resistance wires before fire basing on micro-regional characters. The morphology and elemental compositions of resistance wires surface under normally used, misused and external heating conditions were respectively studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The results show that the normally used wire has a smooth surface and stable metal composition. While the resistance wire under misused condition for the certain time could be characterized as a coarse surface covered by compacted and silica-embedded oxide layer, and the proportion of elemental compositions of different metals is also changed with higher content of Al and lower content of Fe and Cr. The external heating condition has little influence on inside wires. The mechanism of changes formed under misused condition was explained. We demonstrate that this approach is practical and functional to aid fire investigators in determining the cause of related fires.
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Association of heme oxygenase-1 with the risk of polycystic ovary syndrome in non-obese women.
Hum. Reprod.
PUBLISHED: 02-28-2014
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Is circulating heme oxygenase-1 (HO-1) associated with the risk of polycystic ovary syndrome (PCOS)?
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Transcriptional landscape of the prenatal human brain.
Nature
PUBLISHED: 02-26-2014
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The anatomical and functional architecture of the human brain is mainly determined by prenatal transcriptional processes. We describe an anatomically comprehensive atlas of the mid-gestational human brain, including de novo reference atlases, in situ hybridization, ultra-high-resolution magnetic resonance imaging (MRI) and microarray analysis on highly discrete laser-microdissected brain regions. In developing cerebral cortex, transcriptional differences are found between different proliferative and post-mitotic layers, wherein laminar signatures reflect cellular composition and developmental processes. Cytoarchitectural differences between human and mouse have molecular correlates, including species differences in gene expression in subplate, although surprisingly we find minimal differences between the inner and outer subventricular zones even though the outer zone is expanded in humans. Both germinal and post-mitotic cortical layers exhibit fronto-temporal gradients, with particular enrichment in the frontal lobe. Finally, many neurodevelopmental disorder and human-evolution-related genes show patterned expression, potentially underlying unique features of human cortical formation. These data provide a rich, freely-accessible resource for understanding human brain development.
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100 Tbit/s free-space data link enabled by three-dimensional multiplexing of orbital angular momentum, polarization, and wavelength.
Opt Lett
PUBLISHED: 02-25-2014
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We investigate the orthogonality of orbital angular momentum (OAM) with other multiplexing domains and present a free-space data link that uniquely combines OAM-, polarization-, and wavelength-division multiplexing. Specifically, we demonstrate the multiplexing/demultiplexing of 1008 data channels carried on 12 OAM beams, 2 polarizations, and 42 wavelengths. Each channel is encoded with 100 Gbit/s quadrature phase-shift keying data, providing an aggregate capacity of 100.8 Tbit/s (12×2×42×100 Gbit/s).
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Acute effect of glucose on cerebral blood flow, blood oxygenation, and oxidative metabolism.
Hum Brain Mapp
PUBLISHED: 02-12-2014
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While it is known that specific nuclei of the brain, for example hypothalamus, contain glucose-sensing neurons thus their activity is affected by blood glucose level, the effect of glucose modulation on whole-brain metabolism is not completely understood. Several recent reports have elucidated the long-term impact of caloric restriction on the brain, showing that animals under caloric restriction had enhanced rate of tricarboxylic acid cycle (TCA) cycle flux accompanied by extended life span. However, acute effect of postprandial blood glucose increase has not been addressed in detail, partly due to a scarcity and complexity of measurement techniques. In this study, using a recently developed noninvasive MR technique, we measured dynamic changes in global cerebral metabolic rate of O2 (CMRO2 ) following a 50 g glucose ingestion (N?=?10). A time dependent decrease in CMRO2 was observed, which was accompanied by a reduction in oxygen extraction fraction (OEF) with unaltered cerebral blood flow (CBF). At 40 min post-ingestion, the amount of CMRO2 reduction was 7.8?±?1.6%. A control study without glucose ingestion was performed (N?=?10), which revealed no changes in CMRO2 , CBF, or OEF, suggesting that the observations in the glucose study was not due to subject drowsiness or fatigue after staying inside the scanner. These findings suggest that ingestion of glucose may alter the rate of cerebral metabolism of oxygen in an acute setting. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc.
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Reconfigurable 2 × 2 orbital angular momentum based optical switching of 50-Gbaud QPSK channels.
Opt Express
PUBLISHED: 02-12-2014
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We experimentally demonstrate a reconfigurable 2 × 2 switch for orbital angular momentum (OAM) multiplexed data-carrying optical beams. The switch can be configured to operate in either 'cross' or 'bar' state for each of the input OAM-multiplexed channels. The switching operation is demonstrated by operating the switch in five different configurations for the four OAM-multiplexed 50 Gbaud QPSK channels. An OSNR penalty < 2.5 dB is observed for the switched beams.
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A novel mutation of GATA4 (K319E) is responsible for familial atrial septal defect and pulmonary valve stenosis.
Gene
PUBLISHED: 02-06-2014
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Congenital heart disease (CHD) is the most common birth defect in humans, and the etiology of most CHD remains to be elusive. Atrial septal defect (ASD) makes up 30–40% of all adult CHDs and is thought to be genetically heterogeneous. Previous studies have demonstrated that mutations in transcription factors e.g. NKX2.5, GATA4, and TBX5 contribute to congenital ASD. In this study, we investigate a family of three generations with seven patients with ASD and pulmonary valve stenosis (PS). A novel GATA4 mutation, c.955ANG (p.K319E), was identified and co-segregated with the affected patients in this family. This mutation was predicted to be deleterious by three different bioinformatics programs (The polyphen2, SIFT and MutationTaster). Our finding expands the spectrum of GATA4 mutations and provides additional support that GATA4 plays important roles in cardiac development.
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Dimeric structure of pseudokinase RNase L bound to 2-5A reveals a basis for interferon-induced antiviral activity.
Mol. Cell
PUBLISHED: 01-28-2014
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RNase L is an ankyrin repeat domain-containing dual endoribonuclease-pseudokinase that is activated by unusual 2,'5'-oligoadenylate (2-5A) second messengers and which impedes viral infections in higher vertebrates. Despite its importance in interferon-regulated antiviral innate immunity, relatively little is known about its precise mechanism of action. Here we present a functional characterization of 2.5 Å and 3.25 Å X-ray crystal and small-angle X-ray scattering structures of RNase L bound to a natural 2-5A activator with and without ADP or the nonhydrolysable ATP mimetic AMP-PNP. These studies reveal how recognition of 2-5A through interactions with the ankyrin repeat domain and the pseudokinase domain, together with nucleotide binding, imposes a rigid intertwined dimer configuration that is essential for RNase catalytic and antiviral functions. The involvement of the pseudokinase domain of RNase L in 2-5A sensing, nucleotide binding, dimerization, and ribonuclease functions highlights the evolutionary adaptability of the eukaryotic protein kinase fold.
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Genetic evidence that Nkx2.2 and Pdgfra are major determinants of the timing of oligodendrocyte differentiation in the developing CNS.
Development
PUBLISHED: 01-23-2014
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In the central nervous system (CNS), oligodendrocyte maturation and axonal myelination occur on a predictable schedule, but the underlying timing mechanisms are largely unknown. In the present study, we demonstrate that Nkx2.2 homeodomain transcription factor is a key regulator for the timing of oligodendrocyte differentiation during development. Whereas induced expression of Nkx2.2 in early oligodendrocyte precursor cells (OPCs) causes precocious differentiation of oligodendrocytes, conditional ablation of Nkx2.2 temporally delays oligodendrocyte maturation. Moreover, Nkx2.2 can directly bind to the promoter of platelet-derived growth factor receptor alpha (Pdgfra) and repress its gene expression. Genetic ablation of Pdgfra mimics the effect of Nkx2.2 overexpression in accelerating OPC differentiation in the developing spinal cord. Together, our findings strongly suggest that Nkx2.2 functions as a major 'switch' to turn off Pdgfra signaling in OPCs and initiate the intrinsic program for oligodendrocyte differentiation.
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Rich soil carbon and nitrogen but low atmospheric greenhouse gas fluxes from North Sulawesi mangrove swamps in Indonesia.
Sci. Total Environ.
PUBLISHED: 01-16-2014
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The soil to atmosphere fluxes of greenhouse gases N2O, CH4 and CO2 and their relationships with soil characteristics were investigated in three tropical oceanic mangrove swamps (Teremaal, Likupang and Kema) in North Sulawesi, Indonesia. Mangrove soils in North Sulawesi were rich in organic carbon and nitrogen, but the greenhouse gas fluxes were low in these mangroves. The fluxes ranged -6.05-13.14 ?mol m(-2)h(-1), -0.35-0.61 ?mol m(-2)h(-1) and -1.34-3.88 mmol m(-2)h(-1) for N2O, CH4 and CO2, respectively. The differences in both N2O and CH4 fluxes among different mangrove swamps and among tidal positions in each mangrove swamp were insignificant. CO2 flux was influenced only by mangrove swamps and the value was higher in Kema mangrove. None of the measured soil parameters could explain the variation of CH4 fluxes among the sampling plots. N2O flux was negatively related to porewater salinity, while CO2 flux was negatively correlated with water content and organic carbon. This study suggested that the low gas emissions due to slow metabolisms would lead to the accumulations of organic matters in North Sulawesi mangrove swamps.
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Blood-nerve barrier dysfunction contributes to the generation of neuropathic pain and allows targeting of injured nerves for pain relief.
Pain
PUBLISHED: 01-15-2014
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The blood-nerve barrier (BNB) is a selectively permeable barrier that creates an immunologically and biochemically privileged space for peripheral axons and supporting cells. The breakdown of the BNB allows access of blood-borne (hematogenous) cells and molecules to the endoneurium to engage in the local inflammatory cascade. This process was examined in a mouse model of trauma-associated neuropathic pain. The impact of nerve injury-triggered opening of the BNB in the development of chronic pain behavior was investigated. Partial ligation of the sciatic nerve led to a long-lasting disruption of the BNB distal to the site of injury. Vascular endothelial growth factor (VEGF) was expressed by resident macrophages after nerve injury. Intraneural injection of VEGF decreased mechanical thresholds while opening the BNB. Serum from nerve-injured or lipopolysaccharide-treated animals elicited mechanical allodynia in naive animals, when allowed to bypass the BNB by intraneural injection. Intraneural injection of fibrinogen, a clotting protein in plasma that was found to deposit in the nerve after nerve injury, also produced a decrease in mechanical thresholds when introduced into naive nerves. These results demonstrate that blood-borne molecules may play a role in the generation of neuropathic pain, suggesting that pain may be driven from infection or injury, at a distance from the nervous system. Furthermore, the breakdown of the BNB in neuropathic conditions was exploited to permit the entry of analgesic molecules that typically cannot pass the BNB, such as ProToxin-II, a BNB-impermeable Nav1.7 inhibitor. Therapeutics utilizing this mechanism could have selective access to injured nerves over healthy tissues.
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Quantitative assessment of global cerebral metabolic rate of oxygen (CMRO2) in neonates using MRI.
NMR Biomed
PUBLISHED: 01-07-2014
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The cerebral metabolic rate of oxygen (CMRO2) is the rate of oxygen consumption by the brain, and is thought to be a direct index of energy homeostasis and brain health. However, in vivo measurement of CMRO2 is challenging, in particular for the neonatal population, in whom conventional radiotracer methods are not applicable because of safety concerns. In this study, we propose a method to quantify global CMRO2 in neonates based on arteriovenous differences in oxygen content, and employ separate measurements of oxygenation and cerebral blood flow (CBF) parameters. Specifically, arterial and venous oxygenation levels were determined with pulse oximetry and the novel T2 relaxation under spin tagging (TRUST) MRI, respectively. Global CBF was measured with phase contrast (PC) flow velocity MRI. The proposed method was implemented on a standard 3-T MRI scanner without the need for any exogenous tracers, and the total scan duration was less than 5?min. We demonstrated the feasibility of this method in 12 healthy neonates within an age range of 35-42 gestational weeks. CMRO2 values were successfully obtained from 10 neonates. It was found that the average CMRO2 in this age range was 38.3?±?17.7?µmol/100?g/min and was positively correlated with age (p?=?0.007; slope, 5.2?µmol/100?g/min per week), although the highest CMRO2 value in this age range was still less than half of the adult level. Test-retest studies showed a coefficient of variation of 5.8?±?2.2% between repeated CMRO2 measurements. In addition, given the highly variable blood flow velocity within this age range, it is recommended that the TRUST labeling thickness and position should be determined on a subject-by-subject basis, and an automatic algorithm was developed for this purpose. Although this method provides a global CMRO2 measure only, the clinical significance of an energy consumption marker and the convenience of this technique may make it a useful tool in the functional assessment of the neonatal population.
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Integrated analysis of expression profiling data identifies three genes in correlation with poor prognosis of triple-negative breast cancer.
Int. J. Oncol.
PUBLISHED: 01-04-2014
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Triple-negative breast cancer (TNBC) shows more aggressive clinical behavior and poorer outcome than non-triple-negative breast cancer (NTNBC), and cannot be treated either via endocrine therapy or by Trastuzumab. For TNBC, chemotherapy is currently the mainstay of systemic medical treatment, the lack of more efficient options of treatment has been a problem in breast cancer prevention. In this study, we aimed to find genes related to prognosis in TNBC by bioinformatic analysis and to provide therapeutic candidates for TNBC treatment. We compared the differences in gene expression levels between cancer patients and healthy individuals across five breast cancer microarray databases to generate a gene cohort specifically upregulated in the NTNBC subtype, whose expression levels are ?2-fold higher in TNBC compared to NTNBC and healthy individuals. Another two databases with clinical information were applied for following Kaplan-Meier analysis, and high expression of BIRC5, CENPA and FAM64A in this cohort were found to be related to poor survival (OS, DMFS, DFS and RFS). This correlation was also seen in patients at early stages and grades. On the other hand, the outcome of patients with synchronous upregulation of these three genes was the worst, while those with synchronous low gene level was the best. In conclusion, BIRC5, CENPA and FAM64A are specifically upregulated in TNBC, and the high expression of these three genes is associated with poor breast cancer prognosis, suggesting their clinical implication as therapeutic targets in TNBC.
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Control of astrocyte progenitor specification, migration and maturation by nkx6.1 homeodomain transcription factor.
PLoS ONE
PUBLISHED: 01-01-2014
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Although astrocytes are the most abundant cell type in the central nervous system (CNS), little is known about their molecular specification and differentiation. It has previously been reported that transcription factor Nkx6.1 is expressed in neuroepithelial cells that give rise to astrocyte precursors in the ventral spinal cord. In the present study, we systematically investigated the function of Nkx6.1 in astrocyte development using both conventional and conditional Nkx6.1 mutant mice. At early postnatal stages, Nkx6.1 was expressed in a subpopulation of astrocytes in the ventral spinal cord. In the conventional Nkx6.1KO spinal cord, the initial specification of astrocyte progenitors was affected by the mutation, and subsequent migration and differentiation were disrupted in newborn mice. In addition, the development of VA2 subtype astrocytes was also inhibited in the white matter. Further studies with Nkx6.1 conditional mutants revealed significantly delayed differentiation and disorganized arrangement of fibrous astrocytes in the ventral white matter. Together, our studies indicate that Nkx6.1 plays a vital role in astrocyte specification and differentiation in the ventral spinal cord.
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Microstructure, length, and connection of limbic tracts in normal human brain development.
Front Aging Neurosci
PUBLISHED: 01-01-2014
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The cingulum and fornix play an important role in memory, attention, spatial orientation, and feeling functions. Both microstructure and length of these limbic tracts can be affected by mental disorders such as Alzheimer's disease, depression, autism, anxiety, and schizophrenia. To date, there has been little systematic characterization of their microstructure, length, and functional connectivity in normally developing brains. In this study, diffusion tensor imaging (DTI) and resting state functional MRI (rs-fMRI) data from 65 normally developing right-handed subjects from birth to young adulthood was acquired. After cingulate gyrus part of the cingulum (cgc), hippocampal part of the cingulum (cgh) and fornix (fx) were traced with DTI tractography, absolute and normalized tract lengths and DTI-derived metrics including fractional anisotropy, mean, axial, and radial diffusivity were measured for traced limbic tracts. Free water elimination (FWE) algorithm was adopted to improve accuracy of the measurements of DTI-derived metrics. The role of these limbic tracts in the functional network at birth and adulthood was explored. We found a logarithmic age-dependent trajectory for FWE-corrected DTI metric changes with fast increase of microstructural integrity from birth to 2?years old followed by a slow increase to 25?years old. Normalized tract length of cgc increases with age, while no significant relationship with age was found for normalized tract lengths of cgh and fx. Stronger microstructural integrity on the left side compared to that of the right side was found. With integrated DTI and rs-fMRI, the key connectional role of cgc and cgh in the default mode network was confirmed as early as birth. Systematic characterization of length and DTI metrics after FWE correction of limbic tracts offers insight into their morphological and microstructural developmental trajectories. These trajectories may serve as a normal reference for pediatric patients with mental disorders.
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Comparative transcriptomic characterization of the early development in Pacific white shrimp Litopenaeus vannamei.
PLoS ONE
PUBLISHED: 01-01-2014
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Penaeid shrimp has a distinctive metamorphosis stage during early development. Although morphological and biochemical studies about this ontogeny have been developed for decades, researches on gene expression level are still scarce. In this study, we have investigated the transcriptomes of five continuous developmental stages in Pacific white shrimp (Litopenaeus vannamei) with high throughput Illumina sequencing technology. The reads were assembled and clustered into 66,815 unigenes, of which 32,398 have putative homologues in nr database, 14,981 have been classified into diverse functional categories by Gene Ontology (GO) annotation and 26,257 have been associated with 255 pathways by KEGG pathway mapping. Meanwhile, the differentially expressed genes (DEGs) between adjacent developmental stages were identified and gene expression patterns were clustered. By GO term enrichment analysis, KEGG pathway enrichment analysis and functional gene profiling, the physiological changes during shrimp metamorphosis could be better understood, especially histogenesis, diet transition, muscle development and exoskeleton reconstruction. In conclusion, this is the first study that characterized the integrated transcriptomic profiles during early development of penaeid shrimp, and these findings will serve as significant references for shrimp developmental biology and aquaculture research.
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Berberine attenuates axonal transport impairment and axonopathy induced by Calyculin A in N2a cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Berberine is a primary component of the most functional extracts of Coptidis rhizome used in traditional Chinese medicine for centuries. Recent reports indicate that Berberine has the potential to prevent and treat Alzheimer's disease (AD). The previous studies reported that Calyculin A (CA) impaired the axonal transport in neuroblastoma-2a (N2a) cells. Berberine attenuated tau hyperphosphorylation and cytotoxicity induced by CA. Our study aimed at investigating the effects of Berberine on the axonal transport impairment induced by CA in N2a cells. The results showed that Berberine could protect the cell from CA -induced toxicity in metabolism and viability, as well as hyperphosphorylation of tau and neurofilaments (NFs). Furthermore, Berberine could reverse CA-induced axonal transport impairment significantly. Berberine also partially reversed the phosphorylation of the catalytic subunit of PP-2A at Tyrosine 307, a crucial site negatively regulating the activity of PP-2A, and reduced the levels of malondialdehyde and the activity of superoxide dismutase, markers of oxidative stress, induced by CA. The present work for the first time demonstrates that Berberine may play a role in protecting against CA-induced axonal transport impairment by modulating the activity of PP-2A and oxidative stress. Our findings also suggest that Berberine may be a potential therapeutic drug for AD.
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[Study on biological characteristics of Cordyceps ramosa mycelia].
Zhong Yao Cai
PUBLISHED: 12-31-2013
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To study the biological characteristics of Cordyceps ramosa mycelia.
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Development of Human Brain Structural Networks Through Infancy and Childhood.
Cereb. Cortex
PUBLISHED: 12-17-2013
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During human brain development through infancy and childhood, microstructural and macrostructural changes take place to reshape the brains structural networks and better adapt them to sophisticated functional and cognitive requirements. However, structural topological configuration of the human brain during this specific development period is not well understood. In this study, diffusion magnetic resonance image (dMRI) of 25 neonates, 13 toddlers, and 25 preadolescents were acquired to characterize network dynamics at these 3 landmark cross-sectional ages during early childhood. dMRI tractography was used to construct human brain structural networks, and the underlying topological properties were quantified by graph-theory approaches. Modular organization and small-world attributes are evident at birth with several important topological metrics increasing monotonically during development. Most significant increases of regional nodes occur in the posterior cingulate cortex, which plays a pivotal role in the functional default mode network. Positive correlations exist between nodal efficiencies and fractional anisotropy of the white matter traced from these nodes, while correlation slopes vary among the brain regions. These results reveal substantial topological reorganization of human brain structural networks through infancy and childhood, which is likely to be the outcome of both heterogeneous strengthening of the major white matter tracts and pruning of other axonal fibers.
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Reconfigurable orbital angular momentum and polarization manipulation of 100??Gbit/s QPSK data channels.
Opt Lett
PUBLISHED: 12-11-2013
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We demonstrate reconfigurable orbital angular momentum (OAM) and polarization manipulation of OAM- and polarization-multiplexed 100??Gbit/s quadrature phase shift keying (QPSK) data channels. Each data channels OAM value and its polarization state can be arbitrarily changed by taking advantage of the unique wavefront profile of OAM beams using liquid crystal on silicon-based spatial light modulators. The manipulation operation introduces a power penalty of <1??dB for 100??Gbit/s QPSK signals.
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Atmospheric turbulence effects on the performance of a free space optical link employing orbital angular momentum multiplexing.
Opt Lett
PUBLISHED: 12-11-2013
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We experimentally investigate the performance of an orbital angular momentum (OAM) multiplexed free space optical (FSO) communication link through emulated atmospheric turbulence. The turbulence effects on the crosstalk and system power penalty of the FSO link are characterized. The experimental results show that the power of the transmitted OAM mode will tend to spread uniformly onto the neighboring mode in medium-to-strong turbulence, resulting in severe crosstalk at the receiver. The power penalty is found to exceed 10 dB in a weak-to-medium turbulence condition due to the turbulence-induced crosstalk and power fluctuation of the received signal.
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Liquid-crystal-on-silicon-based optical add/drop multiplexer for orbital-angular-momentum-multiplexed optical links.
Opt Lett
PUBLISHED: 11-28-2013
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We designed an optical add/drop multiplexer for orbital-angular-momentum (OAM)-multiplexed data links by taking advantage of the ring-shaped intensity profile of OAM beams. We demonstrated adding/dropping a single OAM beam from three multiplexed OAM beams using liquid-crystal-on-silicon-based diffraction optical elements. For multiplexed OAM beams carrying 100??Gbit/s quadrature phase-shift-keying data, a power penalty of <2??dB is observed to achieve a bit-error rate of 2.0×10-3 for each channel of the add/drop multiplexer.
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Reconfigurable switching of orbital-angular-momentum-based free-space data channels.
Opt Lett
PUBLISHED: 11-28-2013
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Light beams can carry orbital angular momentum (OAM) such that a helical phase front twists along the direction of propagation. OAM beams have been demonstrated in a wide variety of applications and have been found to offer a new orthogonal degree of freedom for multiplexing independent data streams for high-capacity point-to-point optical communications. However, to enable their efficient use in reconfigurable networks, approaches must be developed to manipulate OAM beams. We demonstrate OAM-based reconfigurable optical switching functions among multiple OAM beams. Selective data switching among three 100??Gb/s quadrature phase-shift keying OAM channels was achieved with a 2.1 dB optical signal-to-noise ratio penalty. The scheme of selective OAM-beam manipulation can be potentially cascaded to realize an arbitrary n×n switching function.
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Assessment of 64-row computed tomographic angiography for diagnosis and pretreatment planning in pulmonary sequestration.
Radiol Med
PUBLISHED: 11-15-2013
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This study was done to evaluate the clinical implications and results of a prospective protocol using 64-row computed tomographic angiography (CTA) for diagnosis and pre-treatment planning in pulmonary sequestration (PS).
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Rose-bengal-conjugated gold nanorods for in vivo photodynamic and photothermal oral cancer therapies.
Biomaterials
PUBLISHED: 11-01-2013
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Gold nanorods (GNRs) conjugated with rose bengal (RB) molecules exhibit efficient singlet oxygen generation when illuminated by 532 nm green light and high photothermal efficiency under 810 nm near-infrared (NIR) irradiation. In vitro experiments show that reactive oxygen species generated by green light and hyperthermia produced by NIR light constitute two different mechanisms for cancer cell death. The RB-GNRs also exhibit improved photodynamic efficacy by enhancing the uptake of RB by cancer cells. In vivo experiments are conducted on hamster cheek pouches to resemble the human oral cancer conditions more accurately to assess the therapeutic effectiveness. Compared to the single photodynamic therapy (PDT) or photothermal therapy (PTT), the RB-GNRs with combined PDT-PTT capabilities provide better therapeutic effects against oral cancer and have large potential in cancer treatment.
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Multicasting in a spatial division multiplexing system based on optical orbital angular momentum.
Opt Lett
PUBLISHED: 10-02-2013
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We report multicasting data from a single orbital angular momentum (OAM) spatial channel onto multiple OAM channels of equally spaced OAM charge numbers. The designed sliced phase patterns for multicasting are loaded on the spatial light modulator. By optimizing the design of the phase pattern, the power of multicasted OAM channels can be equalized. We experimentally demonstrate multicasting five and seven OAM channels from a single-input OAM channel carrying a 100??Gbit/s quadrature phase-shift keying (QPSK) data stream.
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Tanshinone IIA Exhibits Anticonvulsant Activity in Zebrafish and Mouse Seizure Models.
ACS Chem Neurosci
PUBLISHED: 09-06-2013
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Danshen or Chinese red sage (Salvia miltiorrhiza, Bunge) is used by traditional Chinese medicine (TCM) practitioners to treat neurological, cardiovascular, and cerebrovascular disorders and is included in some TCM formulations to control epileptic seizures. In this study, acetonic crude extracts of danshen inhibited pentylenetetrazol (PTZ)-induced seizure activity in zebrafish larvae. Subsequent zebrafish bioassay-guided fractionation of the extract resulted in the isolation of four major tanshinones, which suppressed PTZ-induced activity to varying degrees. One of the active tanshinones, tanshinone IIA, also reduced c-fos expression in the brains of PTZ-exposed zebrafish larvae. In rodent seizure models, tanshinone IIA showed anticonvulsive activity in the mouse 6-Hz psychomotor seizure test in a biphasic manner and modified seizure thresholds in a complex manner for the mouse i.v. PTZ seizure assay. Interestingly, tanshinone IIA is used as a prescription drug in China to address cerebral ischemia in patients. Here, we provide the first in vivo evidence demonstrating that tanshinone IIA has anticonvulsant properties as well.
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[Effect of manual cleaning and machine cleaning for dental handpiece].
Hua Xi Kou Qiang Yi Xue Za Zhi
PUBLISHED: 09-03-2013
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Comparing the dental handpiece s cleaning effect between manual cleaning and machine cleaning.
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Streptomyces coelicolor encodes a urate-responsive transcriptional regulator with homology to PecS from plant pathogens.
J. Bacteriol.
PUBLISHED: 08-30-2013
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Many transcriptional regulators control gene activity by responding to specific ligands. Members of the multiple-antibiotic resistance regulator (MarR) family of transcriptional regulators feature prominently in this regard, and they frequently function as repressors in the absence of their cognate ligands. Plant pathogens such as Dickeya dadantii encode a MarR homolog named PecS that controls expression of a gene encoding the efflux pump PecM in addition to other virulence genes. We report here that the soil bacterium Streptomyces coelicolor also encodes a PecS homolog (SCO2647) that regulates a pecM gene (SCO2646). S. coelicolor PecS, which exists as a homodimer, binds the intergenic region between pecS and pecM genes with high affinity. Several potential PecS binding sites were found in this intergenic region. The binding of PecS to its target DNA can be efficiently attenuated by the ligand urate, which also quenches the intrinsic fluorescence of PecS, indicating a direct interaction between urate and PecS. In vivo measurement of gene expression showed that activity of pecS and pecM genes is significantly elevated after exposure of S. coelicolor cultures to urate. These results indicate that S. coelicolor PecS responds to the ligand urate by attenuated DNA binding in vitro and upregulation of gene activity in vivo. Since production of urate is associated with generation of reactive oxygen species by xanthine dehydrogenase, we propose that PecS functions under conditions of oxidative stress.
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High level of serum AMBP is associated with poor response to paclitaxel-capecitabine chemotherapy in advanced gastric cancer patients.
Med. Oncol.
PUBLISHED: 08-23-2013
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Gastric cancer is one of the most common human cancers and ranks the second in the global cancer-related mortality. The clinical outcome of patients with advanced gastric cancer (AGC) is markedly dependent on their response to the chemotherapy. Paclitaxel plus capecitabine, as a first-line regimen, is widely administrated in AGC patients, but more than a half of the patients have a poor response, possibly due to their resistance to the treatment. Therefore, it is important to identify potential responders to improve the efficacy of the chemotherapy. In the present study, we used an isobaric tag approach for relative and absolute quantification combined with ESI-QUAD-TOF/MS to identify potential predictive biomarkers for the chemotherapy. We found 211 serum proteins, and confirmed 17 candidates that were differentially present in the progression of disease (PD) group and the partial response (PR) group to the treatment of paclitaxel plus capecitabine. In further validation of the 17 candidates in the set of 12 PD and 12 PR AGC patients, we identified a higher level of AMBP (Alpha-1-Microglobulin/Bikunin Precursor) in the sera of PD patients than of the PR patients assayed by ELISA (9.13 ± 0.45 vs. 8.11 ± 0.26 ?g/mL, p = 0.06) and by the Western blotting (relative gray value 396.4 ± 39.1 vs. 275.0 ± 34.76, p = 0.03), respectively. The receiver operating characteristics curve showed 75% sensitivity and 75% specificity of AMBP in AGC patients treated with the chemotherapy. Our data indicated that the high level of serum AMBP could predict the poor response of the AGC patients treated with the paclitaxel-capecitabine chemotherapy, which could be used as a potential biomarker to identify patients who would benefit from this chemotherapeutic regimen.
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Paralysis following stereotactic spinal irradiation in pigs suggests a tolerance constraint for single-session irradiation of the spinal nerve.
Radiother Oncol
PUBLISHED: 08-14-2013
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Paralysis observed during a study of vertebral bone tolerance to single-session irradiation led to further study of the dose-related incidence of motor peripheral neuropathy.
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Studies on the flavone glycosides from Fructus Kochiae.
J Asian Nat Prod Res
PUBLISHED: 08-06-2013
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A series of flavone glycosides were isolated from Fructus Kochiae for the first time, including two new flavone glycosides. The structures were established by interpretation of their spectroscopic data. Two new flavone glycosides are quercetin 3-O-?-d-apiofuranosyl-(1 ? 2)-?-d-galactopyranosyl-7-O-?-d-glucopyranoside (1) and quercetin 3-O-?-l-rhamnopyranosyl-(1 ? 6)-?-d-galactopyranosyl-7-O-?-d-sophoroside (2). The others are quercetin 7-O-?-d-glucopyranoside (3), quercetin 3-O-?-d-apiofuranosyl-(1 ? 2)-?-d-galactopyranoside (4), quercetin 3-O-?-d-galactopyranosyl-7-O-?-d-glucopyranoside (5), and quercetin 7-O-?-d-sophoroside (6).
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Paper-based plasmonic platform for sensitive, noninvasive, and rapid cancer screening.
Biosens Bioelectron
PUBLISHED: 07-31-2013
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Surface-enhanced Raman scattering (SERS) fingerprints of individual molecules offer the possibility of multiplexing as well as cancer screening. A highly sensitive, noninvasive, and rapid cancer screening platform encompassing exfoliative cytology and paper-based SERS technology is described. The SERS substrate which consists of plasmonic gold nanorods (GNRs) adsorbed on a piece of filter paper forms the flexible and three-dimensional heterogeneous scaffold for cancer screening. Different and reproducible SERS spectra are obtained from normal and cancerous cells due to specific biomolecular changes in cancerous cells. A diagnostic algorithm based on the ratio of the spectra values is adopted to distinguish between cells exfoliated from 20 normal and cancerous tissues, and a high sensitivity of 100% and specificity of 100% are achieved by I1600/1440 (peak ratio of signals at 1600-1440cm(-1)) and I1440/1340 (1440-1340cm(-1)), which is better than I1600/1340 (1600-1340cm(-1)) with a sensitivity of 70% and specificity of 60%. The combination of exfoliative cytology and paper-based plasmonic technology enables highly sensitive, rapid, and non-invasive cancer screening and has large clinical potential.
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Discrimination and simultaneous determination of hydroquinone and catechol by tunable polymerization of imidazolium-based ionic liquid on multi-walled carbon nanotube surfaces.
Anal. Chim. Acta
PUBLISHED: 07-26-2013
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Tunable polymerization of ionic liquid on the surfaces of multi-walled carbon nanotubes (MWCNTs) was achieved by a mild thermal-initiation-free radical reaction of 3-ethy-1-vinylimidazolium tetrafluoroborate in the presence of MWCNTs. Successful modification of polymeric ionic liquid (PIL) on MWCNTs surfaces (PIL-MWCNTs) was demonstrated by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and X-ray photoelectron spectroscopy. The resulting PIL-MWCNTs possessed unique features of high dispersity in aqueous solution and tunable thickness of PIL layer, due to positive imidazole groups along PIL chains and controllable ionic liquid polymerization by tuning the ratio of precursor. Based on cation-? interaction between the positive imidazole groups on PIL-MWCNTs surface and hydroquinone (HQ) or catechol (CC), excellent discrimination ability toward HQ and CC and improved simultaneous detection performance were achieved. The linear range for HQ and CC were 1.0×10(-6) to 5.0×10(-4)M and 1.0×10(-6) to 4.0×10(-4)M, respectively. The detection limit for HQ was 4.0×10(-7)M and for CC 1.7×10(-7)M (S/N=3), correspondingly.
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[Effects of electroacupuncture stimulation of "Fenglong" (ST 40) on expression of liver ATP-binding cassette transporter A 1 mRNA and protein in rats with hyperlipidemia].
Zhen Ci Yan Jiu
PUBLISHED: 07-04-2013
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To observe the effect of electroacupuncture (EA) at "Fenglong" (ST 40) on blood lipid levels and hepatic ATP binding cassette transporter A 1(ABCA 1) mRNA and protein expression in hyperlipidemia rats, so as to study its mechanism underlying improvement of HLP.
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The Ginger-shaped Asteroid 4179 Toutatis: New Observations from a Successful Flyby of Change-2.
Sci Rep
PUBLISHED: 07-03-2013
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On 13 December 2012, Change-2 conducted a successful flyby of the near-Earth asteroid 4179 Toutatis at a closest distance of 770 ± 120 meters from the asteroids surface. The highest-resolution image, with a resolution of better than 3 meters, reveals new discoveries on the asteroid, e.g., a giant basin at the big end, a sharply perpendicular silhouette near the neck region, and direct evidence of boulders and regolith, which suggests that Toutatis may bear a rubble-pile structure. Toutatis maximum physical length and width are (4.75 × 1.95?km) ±10%, respectively, and the direction of the +z axis is estimated to be (250 ± 5°, 63 ± 5°) with respect to the J2000 ecliptic coordinate system. The bifurcated configuration is indicative of a contact binary origin for Toutatis, which is composed of two lobes (head and body). Change-2 observations have significantly improved our understanding of the characteristics, formation, and evolution of asteroids in general.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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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.