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Find video protocols related to scientific articles indexed in Pubmed.
Synthesis of Semiconducting Polymer Microparticles as Solid Ionophore with Abundant Complexing Sites for Long-life Pb(II) Sensors.
ACS Appl Mater Interfaces
PUBLISHED: 11-19-2014
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Intrinsically electrically semiconducting microparticles of semi-ladder poly(m-phenylenediamine-co-2-hydroxy-5-sulfonic aniline) structure containing abundant functional groups like -NH-, -N=, -NH2, -OH, -SO3H as complexation sites, were efficiently synthesized by chemical oxidative copolymerization of m-phenylenediamine and 2-hydroxy-5-sulfonic aniline. The obtained copolymers were found to be non-porous spherical microparticles that were able to achieve greater ?-conjugated structure, smaller particle aggregate size, and stronger interaction with Pb(II) ions than poly(m-phenylenediamine) containing only -NH-, -N=, and -NH2. A potentiometric Pb(II) sensor was fabricated based on the copolymer microparticles as a crucial solid ionophore component within plasticized PVC. The sensor exhibited a Nernstian response to Pb(II) ions over a wide concentration range, together with a fast response, a wide pH range capability, a long lifetime of up to 5 months, and good selectivity over a wide variety of other ions and redox species. The process for synthesizing the microparticles and fabricating the Pb(II)-sensor can be facilely scaled-up for use in the straightforward long-term on-line monitoring of Pb(II) ions in heavily polluted wastewaters. This study develops an understanding of the facile synthesis of conducting microparticles bearing many functional groups and their structures governing the potentiometric susceptibility towards interaction between Pb(II) ions and the microparticles for fabricating robust long-lived Pb(II)-sensor, signifying the potential suitability of such novel materials for inexpensive sensitive detection of Pb(II) ions.
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Polarization-insensitive liquid crystal microlens array with dual focal modes.
Opt Express
PUBLISHED: 11-18-2014
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We demonstrate a liquid crystal (LC) microlens array (MLA) fabricated by LCs possessing negative dielectric anisotropy, in conjunction with a cell with a three-electrode structure. The presented LC MLA is polarization-insensitive and can be operated in both concave and convex modes. The shortest focal length of the LC MLA is -2.54 and 2.22 mm in concave and convex mode, respectively. Disclination lines that are usually observed in conventional hole-patterned LC lens can also be avoided because of the vertical alignment treatment of LCs.
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Antipyretic and anti-asthmatic activities of traditional Chinese herb-pairs, Ephedra and Gypsum.
Chin J Integr Med
PUBLISHED: 11-16-2014
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Mahuang-Shigao herb-pair is a famous formula composed of Ephedra and Gypsum. The herb-pair is frequently used for treating cold symptoms and bronchial asthma in the clinical practice of Chinese medicine (CM). In the present study, we evaluated evidence for the benefit of combined use of Ephedra and Gypsum by analyzing the antipyretic and anti-asthmatic activities of Ephedra-Gypsum.
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Stitching graphene oxide sheets into a membrane at a liquid/liquid interface.
Chem. Commun. (Camb.)
PUBLISHED: 11-10-2014
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Layer-by-layer patterned GO membrane assembling at a liquid/liquid interface was realized using polyetheramine "stitching" molecules with an adjustable hydrophobicity and its thickness can be easily tuned from nanometer to micrometer by controlling reaction kinetics including reactant concentration, reaction time and reaction temperature.
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[Isolation of endophytic fungi from medicinal plant Brucea javanica and their microbial inhibition activity].
Zhong Yao Cai
PUBLISHED: 10-28-2014
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To isolate and identify endophytic fungi from Brucea javanica, and to detect the antimicrobial activity of these strains.
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[Analysis of alarm management and alarm information integration technology for ICU's medical device].
Zhongguo Yi Liao Qi Xie Za Zhi
PUBLISHED: 10-22-2014
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This paper analyzed current problems and challenges facing hospitals in alarm management both abroad and at home. Based on a survey conducted on alarm management in hospitals, plus an analysis on different kinds of data interfaces and data exchange protocols of the medical equipment used in ICUs, a solution of alarm management is put forwarded which is based on alarm information integration and processing. It aims at improving medical equipment alarm management and reducing relevant adverse events.
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Tea drinking and risk of pancreatic cancer.
Chin. Med. J.
PUBLISHED: 10-16-2014
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Epidemiologic studies have reported inconsistent results regarding tea consumption and the risk of pancreatic cancer. This study aimed to investigate whether tea consumption is related to the risk of pancreatic cancer.
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Rotenone Induction of Hydrogen Peroxide Inhibits mTOR-mediated S6K1 and 4E-BP1/eIF4E Pathways, Leading to Neuronal Apoptosis.
Toxicol. Sci.
PUBLISHED: 10-09-2014
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Rotenone, a common pesticide and inhibitor of mitochondrial complex I, induces loss of dopaminergic neurons and consequential aspects of Parkinson's disease (PD). However, the exact mechanism of rotenone neurotoxicity is not fully elucidated. Here, we show that rotenone induced reactive oxygen species (ROS), leading to apoptotic cell death in PC12 cells and primary neurons. Pretreatment with catalase (CAT), a hydrogen peroxide-scavenging enzyme, attenuated rotenone-induced ROS and neuronal apoptosis, implying hydrogen peroxide (H2O2) involved, which was further verified by imaging intracellular H2O2 using a peroxide-selective probe H2DCFDA. Using thenoyltrifluoroacetone (TTFA), antimycin A, or Mito-TEMPO, we further demonstrated rotenone-induced mitochondrial H2O2-dependent neuronal apoptosis. Rotenone dramatically inhibited mTOR-mediated phosphorylation of S6K1 and 4E-BP1, which was also attenuated by CAT in the neuronal cells. Of interest, ectopic expression of wild-type mTOR or constitutively active S6K1, or downregulation of 4E-BP1 partially prevented rotenone-induced H2O2 and cell apoptosis. Furthermore, we noticed that rotenone-induced H2O2 was linked to the activation of caspase-3 pathway. This was evidenced by the finding that pretreatment with CAT partially blocked rotenone-induced cleavages of caspase-3 and poly (ADP-ribose) polymerase. Of note, zVAD-fmk, a pan caspase inhibitor, only partially prevented rotenone-induced apoptosis in PC12 cells and primary neurons. Expression of mTOR-wt, S6K1-ca, or silencing 4E-BP1 potentiated zVAD-fmk protection against rotenone-induced apoptosis in the cells. The results indicate that rotenone induction of H2O2 inhibits mTOR-mediated S6K1 and 4E-BP1/eIF4E pathways, resulting in caspase-dependent and -independent apoptosis in neuronal cells. Our findings suggest that rotenone-induced neuronal loss in PD may be prevented by activating mTOR signaling and/or administering antioxidants.
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Pathways of cerebrospinal fluid outflow: a deeper understanding of resorption.
Neuroradiology
PUBLISHED: 10-08-2014
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Cerebrospinal fluid (CSF) absorption has long been held to predominantly entail drainage into the venous outflow system via the intracranial arachnoid granulations. Newer data suggest pathways involving spinal arachnoid granulations and lymphatic channels may also make substantial contributions to CSF outflow.
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A new learning algorithm for a fully connected neuro-fuzzy inference system.
IEEE Trans Neural Netw Learn Syst
PUBLISHED: 10-08-2014
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A traditional neuro-fuzzy system is transformed into an equivalent fully connected three layer neural network (NN), namely, the fully connected neuro-fuzzy inference systems (F-CONFIS). The F-CONFIS differs from traditional NNs by its dependent and repeated weights between input and hidden layers and can be considered as the variation of a kind of multilayer NN. Therefore, an efficient learning algorithm for the F-CONFIS to cope these repeated weights is derived. Furthermore, a dynamic learning rate is proposed for neuro-fuzzy systems via F-CONFIS where both premise (hidden) and consequent portions are considered. Several simulation results indicate that the proposed approach achieves much better accuracy and fast convergence.
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Oxidation of Microcystin-LR by Ferrate(VI): Kinetics, Degradation Pathways, and Toxicity Assessments.
Environ. Sci. Technol.
PUBLISHED: 10-02-2014
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The presence of the potent cyanotoxin, microcystin-LR (MC-LR), in drinking water sources poses a serious risk to public health. The kinetics of the reactivity of ferrate(VI) (Fe(VI)O4(2-), Fe(VI)) with MC-LR and model compounds (sorbic acid, sorbic alcohol, and glycine anhydride) are reported over a range of solution pH. The degradation of MC-LR followed second-order kinetics with the bimolecular rate constant (kMCLR+Fe(VI)) decreasing from 1.3 ± 0.1 × 10(2) M(-1) s(-1) at pH 7.5 to 8.1 ± 0.08 M(-1) s(-1) at pH 10.0. The specific rate constants for the individual ferrate species were determined and compared with a number of common chemical oxidants employed for water treatment. Detailed product studies using liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) indicated the oxidized products (OPs) were primarily the result of hydroxylation of the aromatic ring, double bond of the methyldehydroalanine (Mdha) amino acid residue, and diene functionality. Products studies also indicate fragmentation of the cyclic MC-LR structure occurs under the reaction conditions. The analysis of protein phosphatase (PP1) activity suggested that the degradation byproducts of MC-LR did not possess significant biological toxicity. Fe(VI) was effective for the degradation MC-LR in water containing carbonate ions and fulvic acid (FA) and in lake water samples, but higher Fe(VI) dosages would be needed to completely remove MC-LR in lake water compared to deionized water.
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Rational Design of Aggregation-Induced Emission Luminogen with Weak Electron Donor-Acceptor Interaction to Achieve Highly Efficient Undoped Bilayer OLEDs.
ACS Appl Mater Interfaces
PUBLISHED: 09-25-2014
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In this work, two tailored luminogens (TPE-NB and TPE-PNPB) consisting of tetraphenylethene (TPE), diphenylamino, and dimesitylboryl as a ?-conjugated linkage, electron donor, and electron acceptor, respectively, are synthesized and characterized. Their thermal stabilities, photophysical properties, solvachromism, fluorescence decays, electronic structures, electrochemical behaviors, and electroluminescence (EL) properties are investigated systematically, and the impacts of electron donor-acceptor (D-A) interaction on optoelectronic properties are discussed. Due to the presence of a TPE unit, both luminogens show aggregation-induced emission, but strong D-A interaction causes a decrease in emission efficiency and red-shifts in photoluminescence and EL emissions. The luminogen, TPE-PNPB, with a weak D-A interaction fluoresces strongly in solid film with a high fluorescence quantum yield of 94%. The trilayer OLED [ITO/NPB (60 nm)/TPE-PNPB (20 nm)/TPBi (40 nm)/LiF (1 nm)/Al (100 nm)] utilizing TPE-PNPB as a light emitter shows a peak luminance of 49?993 cd m(-2) and high EL efficiencies up to 15.7 cd A(-1), 12.9 lm W(-1), and 5.12%. The bilayer OLED [ITO/TPE-PNPB (80 nm)/TPBi (40 nm)/LiF (1 nm)/Al (100 nm)] adopting TPE-PNPB as a light emitter and hole transporter simultaneously affords even better EL efficiencies of 16.2 cd A(-1), 14.4 lm W(-1), and 5.35% in ambient air, revealing that TPE-PNPB is an eximious p-type light emitter.
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Magnetic-graphitic-nanocapsule templated diacetylene assembly and photopolymerization for sensing and multicoded anti-counterfeiting.
Nanoscale
PUBLISHED: 09-25-2014
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Molecular self-assembly, a process to design molecular entities to aggregate into desired structures, represents a promising bottom-up route towards precise construction of functional systems. Here we report a multifunctional, self-assembled system based on magnetic-graphitic-nanocapsule (MGN) templated diacetylene assembly and photopolymerization. The as-prepared assembly system maintains the unique color and fluorescence change properties of the polydiacetylene (PDA) polymers, while also pursues the superior Raman, NIR, magnetic and superconducting properties from the MGN template. Based on both fluorescence and magnetic resonance imaging (MRI) T2 relaxivity, the MGN@PDA system could efficiently monitor the pH variations which could be used as a pH sensor. The MGN@PDA system further demonstrates potential as unique ink for anti-counterfeiting applications. Reversible color change, strong and unique Raman scattering and fluorescence emission, sensitive NIR thermal response, and distinctive magnetic properties afford this assembly system with multicoded anti-counterfeiting capabilities.
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Alkyne-functionalized superstable graphitic silver nanoparticles for Raman imaging.
J. Am. Chem. Soc.
PUBLISHED: 09-23-2014
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Noble metals, especially gold, have been widely used in plasmon resonance applications. Although silver has a larger optical cross section and lower cost than gold, it has attracted much less attention because of its easy corrosion, thereby degrading plasmonic signals and limiting its applications. To circumvent this problem, we report the facile synthesis of superstable AgCu@graphene (ACG) nanoparticles (NPs). The growth of several layers of graphene onto the surface of AgCu alloy NPs effectively protects the Ag surface from contamination, even in the presence of hydrogen peroxide, hydrogen sulfide, and nitric acid. The ACG NPs have been utilized to enhance the unique Raman signals from the graphitic shell, making ACG an ideal candidate for cell labeling, rapid Raman imaging, and SERS detection. ACG is further functionalized with alkyne-polyethylene glycol, which has strong Raman vibrations in the Raman-silent region of the cell, leading to more accurate colocalization inside cells. In sum, this work provides a simple approach to fabricate corrosion-resistant, water-soluble, and graphene-protected AgCu NPs having a strong surface plasmon resonance effect suitable for sensing and imaging.
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Age-related differences in factors associated with the underuse of recommended medications in acute coronary syndrome patients at least one year after hospital discharge.
BMC Cardiovasc Disord
PUBLISHED: 09-19-2014
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Few studies have evaluated age-related predictors associated with the underuse of medications in patients with coronary heart disease (CHD). The objective of this study was to identify age-related differences in the factors associated with the underuse of recommended medications in patients diagnosed with acute coronary syndrome (ACS).
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Preparation and characterization of polyurethane/soluble eggshell membrane nanofibers.
Biomed Mater Eng
PUBLISHED: 09-18-2014
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Superfine Particles (SP) of soluble eggshell membrane and medical grade polyurethane (MPU) blend nanofibers were prepared by electrospinning different blend ratios of SP/MPU suspensions for regeneration of the natural fiber-like structure of the eggshell membrane. The addition of SP had no obvious effect on the electrospinning process of MPU nanofibers, and the SP were randomly dispersed in the MPU nanofibers with no agglomeration of SP when the amount of SP was less than 20 wt%. Although the average diameter of the blend nanofibers is approximately 30% larger than that of the pure MPU nanofibers, they exhibit excellent tensile strength and tensile resilience that are close to those for pure MPU nanofibers. In addition, the blend nanofibers become fully hydrophilic, and the water contact angle of the blend nanofibers decreases dramatically to 0°. Therefore, with the advantages of a collagen ingredient and good hydrophilicity, these blend nanofibers are suitable for applications such as facial masks, wound dressings, and pharmaceutical carrier materials.
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A Crown Ether Decorated Dibenzocoronene Tetracarboxdiimide Chromophore: Synthesis, Sensing, and Self-Organization.
Chem Asian J
PUBLISHED: 09-04-2014
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A macrocyclic dibenzocoronene tetracarboxdiimide containing two benzo-21-crown-7 groups has been synthesized. It shows liquid-crystalline behavior and selectively binds Pb(2+) or K(+) to form 1:2 complexes in solution. The complexation leads to a significant increase of fluorescence; the surface organization of discotic columnar structures, in the solid-state, can be controlled by selective ion binding.
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Fabrication of graphene-isolated-Au-nanocrystal nanostructures for multimodal cell imaging and photothermal-enhanced chemotherapy.
Sci Rep
PUBLISHED: 09-02-2014
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Using nanomaterials to develop multimodal systems has generated cutting-edge biomedical functions. Herein, we develop a simple chemical-vapor-deposition method to fabricate graphene-isolated-Au-nanocrystal (GIAN) nanostructures. A thin layer of graphene is precisely deposited on the surfaces of gold nanocrystals to enable unique capabilities. First, as surface-enhanced-Raman-scattering substrates, GIANs quench background fluorescence and reduce photocarbonization or photobleaching of analytes. Second, GIANs can be used for multimodal cell imaging by both Raman scattering and near-infrared (NIR) two-photon luminescence. Third, GIANs provide a platform for loading anticancer drugs such as doxorubicin (DOX) for therapy. Finally, their NIR absorption properties give GIANs photothermal therapeutic capability in combination with chemotherapy. Controlled release of DOX molecules from GIANs is achieved through NIR heating, significantly reducing the possibility of side effects in chemotherapy. The GIANs have high surface areas and stable thin shells, as well as unique optical and photothermal properties, making them promising nanostructures for biomedical applications.
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A survey of the dummy face and human face stimuli used in BCI paradigm.
J. Neurosci. Methods
PUBLISHED: 08-22-2014
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It was proved that the human face stimulus were superior to the flash only stimulus in BCI system. However, human face stimulus may lead to copyright infringement problems and was hard to be edited according to the requirement of the BCI study. Recently, it was reported that facial expression changes could be done by changing a curve in a dummy face which could obtain good performance when it was applied to visual-based P300 BCI systems. New METHOD: In this paper, four different paradigms were presented, which were called dummy face pattern, human face pattern, inverted dummy face pattern and inverted human face pattern, to evaluate the performance of the dummy faces stimuli compared with the human faces stimuli. Comparison with Existing Method(s): The key point that determined the value of dummy faces in BCI systems were whether dummy faces stimuli could obtain as good performance as human faces stimuli. Online and offline results of four different paradigms would have been obtained and comparatively analyzed.
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Molecular dynamic simulation of the self-assembly of DAP12-NKG2C activating immunoreceptor complex.
PLoS ONE
PUBLISHED: 08-22-2014
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The DAP12-NKG2C activating immunoreceptor complex is one of the multisubunit transmembrane protein complexes in which ligand-binding receptor chains assemble with dimeric signal-transducing modules through non-covalent associations in their transmembrane (TM) domains. In this work, both coarse grained and atomistic molecular dynamic simulation methods were applied to investigate the self-assembly dynamics of the transmembrane domains of the DAP12-NKG2C activating immunoreceptor complex. Through simulating the dynamics of DAP12-NKG2C TM heterotrimer and point mutations, we demonstrated that a five-polar-residue motif including: 2 Asps and 2 Thrs in DAP12 dimer, as well as 1 Lys in NKG2C TM plays an important role in the assembly structure of the DAP12-NKG2C TM heterotrimer. Furthermore, we provided clear evidences to exclude the possibility that another NKG2C could stably associate with the DAP12-NKG2C heterotrimer. Based on the simulation results, we proposed a revised model for the self-assembly of DAP12-NKG2C activating immunoreceptor complex, along with a plausible explanation for the association of only one NKG2C with a DAP12 dimer.
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Synthesis and optophysical properties of dimeric aza-BODIPY dyes with a push-pull benzodipyrrolidone core.
Chem. Commun. (Camb.)
PUBLISHED: 08-19-2014
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A series of benzodipyrrolidone-based dimeric aza-BODIPY dyes with a push-pull structure are synthesized. Single crystal X-ray diffraction demonstrates these extended aza-BODIPY dyes are planar. The resulting aza-BODIPY chromophores exhibit intense absorption in the 450-800 nm regions and possess lower-lying LUMO energy levels. Furthermore, the push-pull substituents on aza-BODIPYs core have a positive effect on their optophysical properties.
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Hierarchical Supramolecular Assembly of Sterically Demanding ?-Systems by Conjugation with Oligoprolines.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-15-2014
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Self-assembly from flexible worm-like threads via bundles of rigid fibers to nanosheets and nanotubes was achieved by covalent conjugation of perylene monoimide (PMI) chromophores with oligoprolines of increasing length. Whereas the chromophoric ?-system and the peptidic building block do not self-aggregate, the covalent conjugates furnish well-ordered supramolecular structures with a common wall/fiber thickness. Their morphology is controlled by the number of repeat units and can be tuned by seemingly subtle structural modifications.
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High delta-like ligand 4 (DLL4) is correlated with peritumoral brain edema and predicts poor prognosis in primary glioblastoma.
Medicine (Baltimore)
PUBLISHED: 08-15-2014
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Delta-like ligand 4 (DLL4), 1 of the 5 known Notch ligands, is involved in a variety of tumor initiation and progression, particularly in the process of tumor angiogenesis. However, the clinical and prognostic significance of DLL4 in glioblastoma have not been fully elucidated.Tumor tissues from 69 glioblastoma patients were analyzed using immunohistochemistry for DLL4 expression. Peritumoral brain edema (PTBE) on preoperative magnetic resonance imaging of these patients and the relationship with DLL4 expression were evaluated. The effect on prognosis was assessed by using the Kaplan-Meier survival and the Cox proportional hazard model.The results showed that elevated DLL4 expression was primarily distributed in the cytoplasm of tumor vascular endothelial cells and rarely detected in tumor cells. Univariate analysis indicated significant correlation of high DLL4 expression with shorter time to progression (TTP) (P?
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[Study on Dendrobium loddigesii Rolfes from different regions and harvest periods by FTIR].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 08-07-2014
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Infrared Spectroscopy (IR) integrated with two dimensional correlation infrared spectroscopy (2DCOS IR) was employed to rapidly discriminate Dendrobium loddigesii Rolfes (DR) from different regions and harvesting periods. The results showed that the IR peaks around 1 035, 1 051, 1 078, 1 156, 1 500, 1 511 and 1 736 cm-1had perceptible differences among DRs from different regions, indicating that different DRs containing remarkable different compositions and contents of polysaccharides, ketones and esters. 2DCOS IR spectra of DRs from Vietnam, Yunnan, Guangxi, Guizhou each had seven, eight, eight, nine auto peaks, respectively; furthermore, DRs from Guagnxi had the strongest peak in 1 220 cm-1, which was distinguish to those of other DRs (980 cm -1). In the IR spectra of DRs from different harvest seasons, the wave number of key peaks in (1 034 approximately1 023)cm- 1, the wave number of minor peaks in (1 6174)cm-1, as well as the presence of peaks in 1 078(1 076, 1 079)cm-1, showed obvious periodic changes with the seasons, which indicated the accumulation of polysaccharides and ketones from DRs displayed an evident periodic variability discipline. The application of FTIR in DRs could facilitate acquiring their growth conditions, composition and content changes, which would be significant in rational exploitations and utilizations of DR
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Effect of superfine grinding on the physico-chemical, morphological and thermogravimetric properties of Lentinus edodes mushroom powders.
J. Sci. Food Agric.
PUBLISHED: 08-05-2014
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Lentinus edodes is an edible mushroom commonly known as shiitake, which is the second most produced and consumed edible mushroom in the world and is an important nutrient source in the human diet. To fully use L. edodes, the mushrooms are occasionally ground into powder as a flavourful and functional food additive.
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Photoelectric covalent organic frameworks: converting open lattices into ordered donor-acceptor heterojunctions.
J. Am. Chem. Soc.
PUBLISHED: 07-01-2014
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Ordered one-dimensional open channels represent the typical porous structure of two-dimensional covalent organic frameworks (COFs). Here we report a general synthetic strategy for converting these open lattice structures into ordered donor-acceptor heterojunctions. A three-component topological design scheme was explored to prepare electron-donating intermediate COFs, which upon click reaction were transformed to photoelectric COFs with segregated donor-acceptor alignments, whereas electron-accepting buckyballs were spatially confined within the nanochannels via covalent anchoring on the channel walls. The donor-acceptor heterojunctions trigger photoinduced electron transfer and allow charge separation with radical species delocalized in the ?-arrays, whereas the charge separation efficiency was dependent on the buckyball content. This new donor-acceptor strategy explores both skeletons and pores of COFs for charge separation and photoenergy conversion.
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Metal nanoparticle-directed NiCo2O4 nanostructure growth on carbon nanofibers with high capacitance.
Chem. Commun. (Camb.)
PUBLISHED: 06-18-2014
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Metal nanoparticles (Ni, Co) decorated on an electrospun carbon nanofiber surface directed the growth of NiCo2O4 into nanorod and nanosheet morphologies. These metal nanoparticles served as a transition layer to strengthen the interface and promote charge transfer between carbon and NiCo2O4 to achieve a high capacitance of 781 F g(-1).
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Ultrafast Cr(VI) removal from polluted water by microwave synthesized iron oxide submicron wires.
Chem. Commun. (Camb.)
PUBLISHED: 06-13-2014
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Iron oxide submicron wires are successfully synthesized via a microwave irradiation method within a short period of 20 s. Upon reduction, this material shows orders of magnitude faster Cr(VI) removal rate than conventional adsorbents. A redox reaction based removal mechanism is revealed instead of adsorption.
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Differential DNA methylation patterns in endo-siRNAs mediated silencing of LINE-1 retrotransposons.
Methods Mol. Biol.
PUBLISHED: 06-13-2014
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Analyzing differences in DNA methylation is a powerful tool for assessing the effect of endo-siRNAs expression in the human genome. Here, we present a simple genome-wide DNA methylation assay that allows for a precise quantitative analysis of differences in the promoter of human long interspersed nuclear element 1 (LINE-1 or L1) retrotransposons in response to endogenous and exogenous expression of endo-siRNAs. Using the DNA bisulfite modification sequencing, we have optimized the method to detect small changes in heterogeneously methylated L1 repeats at multiple regions across the genome. We also provide guidance for analysis of primary bisulfite sequencing data and interpretation of the methylation status using the Web-based bisulfite sequencing DNA methylation (BISMA) analysis. This refined and reproducible assay can be performed even using a small amount of genomic DNA and is suitable for the analysis of clinical tissue samples.
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Convergent heteroditopic cyclo[6]aramides as macrocyclic ion-pair receptors for constructing [2]pseudorotaxanes.
Chem. Commun. (Camb.)
PUBLISHED: 06-12-2014
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A strategy of using amide groups as the only functionality was developed to construct convergent heteroditopic cyclo[6]aramides that are able to strongly bind dibutylammonium chloride in chloroform (>10(5) M(-1)), leading to the formation of [2]pseudorotaxanes.
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Catalytic functionalization of tertiary alcohols to fully substituted carbon centres.
Org. Biomol. Chem.
PUBLISHED: 06-10-2014
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The catalytic nucleophilic substitution of tertiary alcohols using carbon or heteroatom based nucleophiles is a versatile methodology for the efficient, diverse and atom economical construction of fully substituted carbon centres, including both quaternary carbons and heteroatom substituted tetrasubstituted carbons, which only produces water as the by-product. This review summarizes the recent progress in this field, including the catalytic asymmetric studies and their application in the natural product synthesis, briefly discusses the reaction mechanism and challenges, and outlines synthetic opportunities that are still open.
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The complete mitochondrial genome of the Border Collie dog.
Mitochondrial DNA
PUBLISHED: 06-07-2014
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Abstract Border Collie dog is one of the famous breed of dog. In the present work we report the complete mitochondrial genome sequence of Border Collie dog for the first time. The total length of the mitogenome was 16,730?bp with the base composition of 31.6% for A, 28.7% for T, 25.5% for C, and 14.2% for G and an A-T (60.3%)-rich feature was detected. It harbored 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and one non-coding control region (D-loop region). The arrangement of all genes was identical to the typical mitochondrial genomes of dogs.
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Toward perylene dyes by the Hundsdiecker reaction.
Org. Lett.
PUBLISHED: 05-16-2014
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An efficient method to synthesize 3,4,9,10-tetrabromoperylenes is reported under optimized Hunsdiecker conditions. Various octasubstituted perylenes were obtained by reaction of 1,6,7,12-tetrachloro-3,4,9,10-tetrabromoperylene with phenol, trimethylsilyl chloride, cooper cyanide, or sulfur via metal-catalyzed couplings or nucleophilic substitutions. These new perylenes show completely different optical and redox properties, thus opening a facile way to develop new chromophophore structures.
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Inhibiting geranylgeranyltransferase i activity decreases spine density in central nervous system.
Hippocampus
PUBLISHED: 05-14-2014
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Geranylgeranyltransferase I (GGT), a protein prenyltransferase, is responsible for the posttranslational lipidation of Rho GTPases, such as Rac, Rho and Cdc42, all of which play an important role in neuronal synaptogenesis. We previously demonstrated that GGT promotes dendritic morphogenesis in cultured hippocampal neurons and cerebellar slices. We report here that inhibiting GGT activity decreases basal- and activity-dependent changes in spine density as well as in learning and memory ability of mice in vivo. We found that KCl- or bicuculline-induced dendritic spine density increases was abolished by specific GGT inhibitor GGTi-2147 treatment in cultured hippocampal neurons. GGTi-2147 lateral ventricular injection reduced GGT activity and membrane association of Rac and decreased the density of dendritic spines in the mouse hippocampus, frontal cortex and cerebellum. GGTi-2147 administration also impaired learning and memory ability of mice. More importantly, mice exposed to environmental enrichment (EE) showed increased spine density and learning and memory ability, which were significantly reversed by GGTi-2147 administration. These data demonstrate that inhibiting GGT activity prevents both basal- and activity-dependent changes in spine density in central nervous system both in vitro and in vivo. Manipulating GGT activity may be a promising strategy for the therapies of neurodevelopmental disorders, such as autism, depression and schizophrenia. © 2014 Wiley Periodicals, Inc.
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Flow-assisted 2D polymorph selection: stabilizing metastable monolayers at the liquid-solid interface.
J. Am. Chem. Soc.
PUBLISHED: 05-14-2014
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Controlling crystal polymorphism constitutes a formidable challenge in contemporary chemistry. Two-dimensional (2D) crystals often provide model systems to decipher the complications in 3D crystals. In this contribution, we explore a unique way of governing 2D polymorphism at the organic liquid-solid interface. We demonstrate that a directional solvent flow could be used to stabilize crystalline monolayers of a metastable polymorph. Furthermore, flow fields active within the applied flow generate millimeter-sized domains of either polymorph in a controlled and reproducible fashion.
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[Clinical characteristics of young patients with acute myocardial infarction].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 05-14-2014
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To analyze the clinical characteristics of young patients with acute myocardial infarction (AMI), discuss the key points of health education in young patients with AMI, enhance the understanding of patients, and improve the prognosis of AMI in the young patients.
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[Relationship between PMI and relative expression of myocardial various RNAs in rats died of different causes].
Fa Yi Xue Za Zhi
PUBLISHED: 05-09-2014
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To observe the changes of relative expression of myocardial various RNAs in rats died of different causes and their relationship with PMI.
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Co-crystal formation between poly(ethylene glycol) and a small molecular drug griseofulvin.
Chem. Commun. (Camb.)
PUBLISHED: 05-08-2014
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Most of the pharmaceutical co-crystals are formed between drug molecules and small molecular compounds. Here, we demonstrated that a small molecular drug griseofulvin and poly(ethylene glycol) can also form co-crystals.
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Quercetin attenuates doxorubicin cardiotoxicity by modulating Bmi-1 expression.
Br. J. Pharmacol.
PUBLISHED: 04-29-2014
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Doxorubicin-based chemotherapy induces cardiotoxicity, which limits its clinical application. We previously reported the protective effects of quercetin against doxorubicin-induced hepatotoxicity. In this study, we tested the effects of quercetin on the expression of Bmi-1, a protein regulating mitochondrial function and ROS generation, as a mechanism underlying quercetin-mediated protection against doxorubicin-induced cardiotoxicity.
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Kyphoplasty versus vertebroplasty for the treatment of malignant vertebral compression fractures caused by metastases: a retrospective study.
Chin. Med. J.
PUBLISHED: 04-26-2014
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There are few comparative studies regarding kyphoplasty (KP) and vertebroplasty (VP) for the treatment of painful vertebral compression fractures (VCF) in patients with cancer. The purpose of this study is to retrospectively compare KP with VP in pain improvement, cement leakage incidence, and the cost of treatment of malignant VCF.
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The Potential Roles of Cell Surface pHs in Bioactive Peptide Activation.
Chem Biol Drug Des
PUBLISHED: 04-16-2014
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Glycolytic metabolism of cells produces protons that are removed from the cytosol by transport proteins to create a pH difference between the adjacent bulk solution and the cell membrane surface. Therefore, tissue cells have distinct surface pHs because of varied glycocalyx and proton production capability. In this study, we proved the role of cell surface pH in peptide-cell interaction and peptide activation using lytic peptides with pH-dependent activity as probes. Properly, selected peptides could sense the specific pH zones on cells and thus demonstrated varied activity to tissue cells with different surface pHs. For a specific cell, the activity of pH-sensitive peptides changed accordingly as the cell surface pH was tuned up or down by proton channel regulators. Mechanistic studies revealed that cell surface pH directly affected peptide insertion into membranes by altering the secondary structure and aggregation status of membrane-bound pH-sensitive peptides. A pH-sensitive lytic peptide-designed based on the cell surface pH difference between a normal-cancer cell pair showed good selectivity to cancer cells. Therefore, cell surface pHs may present new opportunities to design therapeutic peptides with high cell specificity and selectivity.
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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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Situation-specific factors predicting nonadherence to methadone maintenance treatment: a cross-sectional study using the case-crossover design in Guangzhou, China.
AIDS Care
PUBLISHED: 04-15-2014
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Methadone maintenance treatment (MMT) is a key risk reduction measure for controlling HIV transmission among drug users. Studies using traditional methods exist to distinguish between drop outs and nondrop outs. However, many nondrop outs use MMT discontinuously and no study has identified situation-specific factors predicting their showing or not showing up. This study used a case-crossover design comparing situation-specific factors appearing on the last episode of attendance versus those of the last episode of nonattendance. A total of 133 participants were recruited from two MMT clinics in Guangzhou, China. Participants were asked separately whether various situation-specific factors existed in the last episodes of nonattendance and attendance of MMT. Matched odds ratios (ORs) based on conditional logistic regression analysis were presented. The results showed that the participants attended the MMT clinics on average for 25 days in the last month. Situation-specific factors significantly predicting nonattendance included: (1) physical and mental health status: in illness (OR = 33.0, P < 0.001), in a bad mood (OR = 7.5, P < 0.001), and occurrence of an unhappy event (OR = 18.0, P < 0.001); (2) other engagement: work engagement (OR = 40.0, P < 0.001), trip to other places (OR = 83.0, P < 0.001), and social activities (OR = 10.0, P = 0.012); (3) interpersonal relationship: conflicts with family (OR = 19.0, P = 0.004); and (4) structural situational factors: financial difficulty (OR = 19.0, P = 0.004) and worrying about police arrest (OR = 12.0, P = 0.003). Other factors such as interaction with drug users and heroin use were marginally significant, while reduced methadone dosage was nonsignificant. Interventions to improve MMT adherence need to consider situation-specific factors. Ancillary psychosocial services should be integrated with current MMT; MMT should also provide more flexible services to the clients. Furthermore, efforts should be taken to build up interdisciplinary teams and to connect with MMT in order to provide holistic harm reduction, rehabilitation, and health care.
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[County scale characteristics of CO2 emission's spatial-temporal evolution in the Beijing-Tianjin-Hebei Metropolitan Region].
Huan Jing Ke Xue
PUBLISHED: 04-12-2014
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CO2 emission spatial distribution is characterized by stages. The study on regional distribution characteristics and evolution can supply important evidence for CO2 emission reduction. Based on CO2 emission data of 128 county areas in the Beijing-Tianjin-Hebei Metropolitan Region (BTHMR) from 1990 to 2009, the spatial pattern and spatial dependence of CO2 emission were discussed by using cartogram and spatial autocorrelation analysis methods. The results show that the total emission of CO2 increased year by year. Average annual growth of CO2 emission after 2002 was 3.7 times higher than before. Different cities have different emission growth trends which can be categorized into three types. The spatial pattern of CO2 emission appeared to be the layered cluster. The Global Moran'I decreased from 1.44 in 1990 to 0.09 in 1998 and then increased slowly to 0.10 in 2009. The spatial distribution of high CO2 emission area changed from 'Double Centers' into 'Four Centers' and the spatial distribution of low CO2 emission area changed less. There were four different change types of local spatial autocorrelation: remaining unchanged or weakening in most regions, enhancing in some regions of Tangshan, transforming in some regions of Tianjin and Xuanhua county. Since the spatial pattern and autocorrelation in low/high CO2 emission area bear different evolution process, the local conditions and interactions with perimeter zones should be considered when formulating emission reduction plan. The discussion of spatial pattern and autocorrelation is very important for understanding spatial evolution pattern of CO2 emission and developing strategic emission reduction planning, and also provides a base for the study on low carbon development in metropolitan area.
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Emission of metals from pelletized and uncompressed biomass fuels combustion in rural household stoves in China.
Sci Rep
PUBLISHED: 04-08-2014
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Effort of reducing CO? emissions in developing countries may require an increasing utilization of biomass fuels. Biomass pellets seem well-suited for residential biomass markets. However, there is limited quantitative information on pollutant emissions from biomass pellets burning, especially those measured in real applications. In this study, biomass pellets and raw biomass fuels were burned in a pellet burner and a conventional stove respectively, in rural households, and metal emissions were determined. Results showed that the emission factors (EFs) ranged 3.20-5.57 (Pb), 5.20-7.58 (Cu), 0.11-0.23 (Cd), 12.67-39.00 (As), 0.59-1.31 mg/kg (Ni) for pellets, and 0.73-1.34 (Pb), 0.92-4.48 (Cu), 0.08-0.14 (Cd), 7.29-13.22 (As), 0.28-0.62 (Ni) mg/kg for raw biomass. For unit energy delivered to cooking vessels, the EFs ranged 0.42-0.77 (Pb), 0.79-1.16 (Cu), 0.01-0.03 (Cd), 1.93-5.09 (As), 0.08-0.19 mg/MJ (Ni) for pellets, and 0.30-0.56 (Pb), 0.41-1.86 (Cu), 0.04-0.06 (Cd), 3.25-5.49 (As), 0.12-0.26 (Ni) mg/MJ for raw biomass. This study found that moisture, volatile matter and modified combustion efficiency were the important factors affecting metal emissions. Comparisons of the mass-based and task-based EFs found that biomass pellets produced higher metal emissions than the same amount of raw biomass. However, metal emissions from pellets were not higher in terms of unit energy delivered.
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TGF-?1-induced expression of Id-1 is associated with tumor progression in gastric cancer.
Med. Oncol.
PUBLISHED: 04-02-2014
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Transforming growth factor ?1 (TGF-?1) and inhibitor of differentiation/DNA-binding 1 (Id-1) have been shown to be associated with aggressive metastatic behavior of cancer cells in many malignant tumors. However, their role in gastric cancer (GC) has not been established. In this study, we investigated the relationship between expression of Id-1 and TGF-?1 in GC as well as their association with GC progression. The immunohistochemical analysis of 71 human GC samples indicated that both Id-1 and TGF-?1 were markedly upregulated in tumor tissue compared with the adjacent tissue; in addition, a significant positive correlation was found between the expression levels of Id-1 and TGF-?1 by Pearson's correlation analysis. Furthermore, the investigation of the association of Id-1 and TGF-?1 with patient clinical characteristics revealed that Id-1 expression was significantly correlated with tumor differentiation, while TGF-?1 was associated with lymph node metastasis. The results were validated in vitro by using a GC cell line, AGS. The expression of Id-1 was upregulated at 24 and 48 h after the treatment with TGF-?1, whereas it did not affect the proliferation of cells. TGF-?1 also influenced the expression of N-cadherin and ?-catenin. Our results suggested that Id-1 and TGF-?1 played important roles in the progression of GC, in which Id-1 might act as a downstream mediator of TGF-?1 signaling through a regulatory mechanism involving N-cadherin and ?-catenin. The TGF-?1/Id-1 axis might serve as a future therapeutic target for GC.
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A vehicle detection algorithm based on deep belief network.
ScientificWorldJournal
PUBLISHED: 03-25-2014
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Vision based vehicle detection is a critical technology that plays an important role in not only vehicle active safety but also road video surveillance application. Traditional shallow model based vehicle detection algorithm still cannot meet the requirement of accurate vehicle detection in these applications. In this work, a novel deep learning based vehicle detection algorithm with 2D deep belief network (2D-DBN) is proposed. In the algorithm, the proposed 2D-DBN architecture uses second-order planes instead of first-order vector as input and uses bilinear projection for retaining discriminative information so as to determine the size of the deep architecture which enhances the success rate of vehicle detection. On-road experimental results demonstrate that the algorithm performs better than state-of-the-art vehicle detection algorithm in testing data sets.
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The efficacy and safety of docetaxel plus thalidomide vs. docetaxel alone in patients with androgen-independent prostate cancer: a systematic review.
Sci Rep
PUBLISHED: 03-19-2014
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The aim of this systematic review was taken to investigate the efficacy and safety of docetaxel plus thalidomide vs. docetaxel alone for treating androgen-independent prostate cancer (AIPC). Data were collected from different databases independently by three researchers according to the pre-defined inclusion and exclusion criteria. Total three studies were finally included, indicating that docetaxel plus thalidomide exhibited better survival prognosis and greater prostate-specific antigen (PSA) decline than docetaxel alone. There were no significant differences of hematologic toxicities in two regimens, while the frequency of non-hematologic toxicities was higher in patients with docetaxel plus thalidomide. Briefly, the available evidence indicates potential survival advantage in docetaxel plus thalidomide over docetaxel alone.
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Activation of AMPK and inactivation of Akt result in suppression of mTOR-mediated S6K1 and 4E-BP1 pathways leading to neuronal cell death in in vitro models of Parkinson's disease.
Cell. Signal.
PUBLISHED: 03-17-2014
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Parkinson's disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons. Dysregulation of mammalian target of rapamycin (mTOR) has been implicated in the pathogenesis of PD. However, the underlying mechanism is incompletely elucidated. Here, we show that PD mimetics (6-hydroxydopamine, N-methyl-4-phenylpyridine or rotenone) suppressed phosphorylation of mTOR, S6K1 and 4E-BP1, reduced cell viability, and activated caspase-3 and PARP in PC12 cells and primary neurons. Overexpression of wild-type mTOR or constitutively active S6K1, or downregulation of 4E-BP1 in PC12 cells partially prevented cell death in response to the PD toxins, revealing that mTOR-mediated S6K1 and 4E-BP1 pathways due to the PD toxins were inhibited, leading to neuronal cell death. Furthermore, we found that the inhibition of mTOR signaling contributing to neuronal cell death was attributed to suppression of Akt and activation of AMPK. This is supported by the findings that ectopic expression of constitutively active Akt or dominant negative AMPK?, or inhibition of AMPK? with compound C partially attenuated inhibition of phosphorylation of mTOR, S6K1 and 4E-BP1, activation of caspase-3, and neuronal cell death triggered by the PD toxins. The results indicate that PD stresses activate AMPK and inactivate Akt, causing neuronal cell death via inhibiting mTOR-mediated S6K1 and 4E-BP1 pathways. Our findings suggest that proper co-manipulation of AMPK/Akt/mTOR signaling may be a potential strategy for prevention and treatment of PD.
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Postmortem interval determination using 18S-rRNA and microRNA.
Sci. Justice
PUBLISHED: 02-20-2014
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The importance of determining postmortem interval (PMI) is crucial to criminal, civil and forensic cases. The precise estimation of PMI is a critical step in many death investigations. A technique exploiting the level of RNA, 18S rRNA and microRNA to estimate PMI was investigated. 18S-rRNA is a main ribosomal RNA presented as part of the ribosomal protein complex, while microRNA is a class of small non-coding single-stranded RNA, only 21-25 nucleotides, which has a strong conservation between different species. In this study, heart tissues were removed from adult rats at various postmortem intervals. An efficient extraction and detection protocol to analyze the level of 18S-rRNA and microRNA in postmortem tissue was carried out. The process consists of total RNA extraction, transcription and visualization by quantitative real time PCR. The result indicates a characteristic parabola relationship between postmortem period and Ct values for 18S-rRNA in dead rat hearts. The result indicates that the degradation pattern of tissue 18S-rRNA and microRNA is useful in the determination of the postmortem interval within seven days.
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Cytotoxic effect of icaritin and its mechanisms in inducing apoptosis in human burkitt lymphoma cell line.
Biomed Res Int
PUBLISHED: 02-16-2014
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Icaritin (ICT), a hydrolytic product of icariin from Epimedium genus, exhibits antitumor activities in several human solid-tumor and myeloid leukemia cells with extensive influence on various cell signal molecules, such as MAPKs being involved in cell proliferation and Bcl-2 participating in cell apoptosis. However, the effect of icaritin on Burkitt Lymphoma has not been elucidated. In the present study, we first screened the potential effect of icaritin on Burkitt lymphoma Raji and P3HR-1 cell lines and found that icaritin showed cytotoxicity in both cell lines. We further found that icaritin could significantly inhibit Raji cells proliferation with S-phase arrest of cell cycle and induced cell apoptosis accompanied by activation of caspase-8 and caspase-9 and cleavage of PARP. We also observed that icaritin was able to decrease Bcl-2 levels, thus shifting the Bcl-2/Bax ratio, and it could obviously reduce c-Myc, a specific molecular target in Burkitt lymphoma. Our findings demonstrated that icaritin showed cytotoxicity, inhibited cell growth, caused S arrest, and induced apoptosis in Burkitt lymphoma cells and provided a rationale for the further evaluation of icaritin for Burkitt lymphoma therapy.
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The combined treatment of amyloid-?1-42-stimulated bone marrow-derived dendritic cells plus splenocytes from young mice prevents the development of Alzheimer's disease in APPswe/PSENldE9 mice.
Neurobiol. Aging
PUBLISHED: 02-13-2014
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Anti-amyloid-? (A?) immunotherapy is a potential therapeutic strategy to reduce amyloid plaques and amyloid-associated pathologies in Alzheimer's disease (AD). Immune senescence with aging has also played a crucial role in AD pathogenesis and influences the effect of anti-A? immunotherapy. In this study, a combined treatment of A?1-42-bone marrow-derived dendritic cells (BMDCs) with intraperitoneal injection of splenocytes from young mice was designed as a novel immunotherapy for AD in APPswe/PSEN1de9 transgenic mice models. The results showed that the combined treatment not only elevated the level of anti-A? antibodies but also reduced amyloid plaques in brain and finally ameliorated deterioration of spatial learning and memory in AD mice. Additionally, the results revealed an increase of CD68 positive microglial cells in the vicinity of amyloid plaques in the mouse brain, which was responsible for the enhanced phagocytosis of A? plaques. In conclusion, the A?1-42-BMDCs plus splenocytes treatment improved the phagocytosis of microglia and prevented AD pathology more effectively. This combined immunotherapy provided a promising treatment in preventing the progression of AD in clinical studies in the near future.
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Percutaneous vertebroplasty performed with an 18-gauge needle for treatment of metastatic severe compression fracture of the cervical vertebral body.
J Vasc Interv Radiol
PUBLISHED: 02-10-2014
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Percutaneous vertebroplasty (PVP) is considered technically difficult in patients with severe vertebral body compression, especially in the cervical spine. In this study, PVP was successfully performed with the use of an 18-gauge angiographic needle in four patients with severe cervical compression fractures from metastatic disease. There were no complications, and relief of pain was immediate in all patients. This technique may be an alternative treatment for intractable pain secondary to severe cervical compression fractures.
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Special role of Foxp3 for the specifically altered microRNAs in Regulatory T cells of HCC patients.
BMC Cancer
PUBLISHED: 02-07-2014
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Regulatory T cells (Tregs) exhibit functional abnormalities in the context of hepatocellular carcinoma (HCC). The microRNAs (miRNAs) are identified as the key modulators in Tregs. This study was to explore whether the expression profiles of miRNAs of Tregs were different in HCC-activated Tregs and whether Foxp3 had special effects on them.
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Associations of methylmercury and inorganic mercury between human cord blood and maternal blood: a meta-analysis and its application.
Environ. Pollut.
PUBLISHED: 01-13-2014
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Considering the different ability of placental transfer, an assessment of the cord:maternal blood ratio for both methylmercury (MeHg) and inorganic mercury (IHg) is needed especially for interpreting the low-level prenatal exposure. In this study, we conducted a Monte Carlo-based meta-analysis to comprehensively estimate that ratio for MeHg (RMeHg) and IHg (RIHg). The obtained values followed log-normal distributions, with a mean (standard deviation) of 1.89 (0.98) and 1.01 (0.55) for RMeHg and RIHg, respectively. We also estimated the percentage of MeHg in the blood by means of THg in cord and maternal blood using the RMeHg and RIHg, and obtained a value very close to the measured one (relative deviation, -0.4%). In conclusion, the fetus is exposed to approximately twice as much MeHg and to the same level of IHg as in maternal blood; the introduced model provides a rough but reasonable estimate of the percentage of MeHg in the blood.
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Efficient soybean regeneration and Agrobacterium-mediated transformation using a whole cotyledonary node as an explant.
Biotechnol. Appl. Biochem.
PUBLISHED: 01-10-2014
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An optimized regeneration and Agrobacterium-mediated transformation protocol based on whole cotyledonary node explants was developed in soybean (Glycine max) cultivar Zhong Huang 13. Adding 6-benzylaminopurine (BAP) in a germinating medium could significantly increase regeneration efficiency; the optimal BAP concentration for shoot formation was 0.5 mg/L. The concentrations of plant growth regulators in a shoot induction medium were optimized by the orthogonal test [L9 (3(3) )]. The best combination for shoot regeneration was a medium of Murashige & Skoog salts with B5 vitamins (MSB) supplemented with 3.5 mg/L BAP, 0.2 mg/L indole-3-butyric acid (IBA), and 0.2 mg/L kinetin (KT). Under this favorable condition, one node could regenerate 28-30 shoots. Soybean whole cotyledonary nodes were transformed by inoculation with A. tumefaciens strain EHA105 harboring a vector pBI121 containing a ?-glucuronidase gene (gus). GUS assay, polymerase chain reaction, and Southern blot analysis indicated that the gus gene was transformed into soybean plants with 23.1% transformation efficiency. Transgenic plants could be obtained within 5-6 weeks, which was about 4 weeks less than that of a traditional single cotyledonary node method.
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Cigarette Smoking Promotes Inflammation in Patients with COPD by Affecting the Polarization and Survival of Th/Tregs through Up-Regulation of Muscarinic Receptor 3 and 5 Expression.
PLoS ONE
PUBLISHED: 01-01-2014
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CD4+ T cells in the lung are involved in the pathogenesis of chronic obstructive pulmonary disease (COPD), although CD4+ T cell subsets and the direct effect of smoking on these cells, especially the expression of MRs, have not been comprehensively examined.
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Treg/IL-17 Ratio and Treg Differentiation in Patients with COPD.
PLoS ONE
PUBLISHED: 01-01-2014
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Chronic obstructive pulmonary disease (COPD) is characterized by chronic pulmonary and systematic inflammation. An abnormal adaptive immune response leads to an imbalance between pro- and anti-inflammatory processes. T-helper (Th), T-cytotoxic (Tc) and T-regulatory (Treg) cells may play important roles in immune and inflammatory responses. This study was conducted to clarify the changes and imbalance of cytokines and T lymphocyte subsets in patients with COPD, especially during acute exacerbations (AECOPD).
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Serum amyloid A and clusterin as potential predictive biomarkers for severe hand, foot and mouth disease by 2D-DIGE proteomics analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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Hand, foot, and mouth disease (HFMD) affects more than one million children, is responsible for several hundred child deaths every year in China and is the cause of widespread concerns in society. Only a small fraction of HFMD cases will develop further into severe HFMD with neurologic complications. A timely and accurate diagnosis of severe HFMD is essential for assessing the risk of progression and planning the appropriate treatment. Human serum can reflect the physiological or pathological states, which is expected to be an excellent source of disease-specific biomarkers. In the present study, a comparative serological proteome analysis between severe HFMD patients and healthy controls was performed via a two-dimensional difference gel electrophoresis (2D-DIGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) strategy. Fifteen proteins were identified as differentially expressed in the sera of the severe HFMD patients compared with the controls. The identified proteins were classified into different groups according to their molecular functions, biological processes, protein classes and physiological pathways by bioinformatics analysis. The up-regulations of two identified proteins, serum amyloid A (SAA) and clusterin (CLU), were confirmed in the sera of the HFMD patients by ELISA assay. This study not only increases our background knowledge about and scientific insight into the mechanisms of HFMD, but also reveals novel potential biomarkers for the clinical diagnosis of severe HFMD.
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STAT3 serine 727 phosphorylation influences clinical outcome in glioblastoma.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Besides STAT3 tyrosine 705 phosphorylation (pTyr705-STAT3), phosphorylation of STAT3 at serine 727 (pSer727-STAT3) is shown to contribute to tumorigenesis and be closely related with resistance to radiotherapy and chemotherapy in glioma, but there is currently no study regarding its relevance to prognosis in glioblastoma (GBM). Here, the expression of phosphorylated STAT3 was detected in tumor specimens from 88 patients with newly diagnosed GBM by immunohistochemistry, the Kaplan-Meier survival curve and COX proportional hazards regression model were applied to estimate its influences on progression-free survival (PFS) and overall survival (OS). Immunohistochemical assay showed elevated expression of pSer727-STAT3 in GBM compared with normal brain tissue. Univariate analysis indicated significant correlations of high percentage of pSer727-STAT3 positive tumor cells with shorter PFS (P = 0.006) and OS (P = 0.002). In multivariate analysis, high pSer727-STAT3 expression was demonstrated as an independent unfavorable prognostic indicator for PFS (HR 1.830, P = 0.022) and OS (HR 1.797, P = 0.040). And patients with high expression of both pTyr705-STAT3 and pSer727-STAT3 had a poorer prognosis compared with the remainder (P < 0.005). In conclusion, the high proportion of pSer727-STAT3 positive neoplastic cells in GBM is an independent unfavorable prognostic factor, and increased expression of both pTyr705-STAT3 and pSer727-STAT3 is predictive of poorer clinical outcome, thereby adding to the growing evidence that STAT3 inhibition may be a potential therapeutic strategy in glioblastoma.
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[Identification of the polymorphs of clopidogrel bisulfate based on the steric morphology parameters of crystals].
Yao Xue Xue Bao
PUBLISHED: 12-24-2013
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The crystal form of solid substance had intrinsic correlation with its three dimensional crystal morphology. Based on the characterization of the three dimensional crystal morphology of clopidogrel bisulfate, this research is to establish a model based on the three dimensional morphological parameters. The granular samples composed of polymorphs of clopidogrel bisulfate and microcrystalline cellulose (MCC) were scanned by synchrotron radiation X-ray microscopic CT technology (SR-microCT) and the three dimensional structural models for which were constructed. Seven groups of three dimensional morphological parameters were calculated. Finally, the mathematical model was established with the multi-layer perception (MLP) artificial neutral network methods to identify and predict the polymorphs of clopidogrel bisulfate. The success rate of the model prediction for the polymorphs of clopidogrel bisulfate was 92.7% and the area under the ROC curve was 96.2%. The polymorphs of drugs could be identified and predicted through the numerical description of the three dimensional morphology. The volume, number of the vertices and the surface area were the major determinants for the identification of the polymorphs of clopidogrel bisulfate.
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Green emitting photoproducts from terrylene diimide after red illumination.
J. Am. Chem. Soc.
PUBLISHED: 12-10-2013
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The spectral properties of emissive photoproducts, formed upon 633 nm irradiation of a terrylene diimide dye, were investigated. Ensemble and single-molecule level experiments were conducted by immobilizing the TDI dye molecules in a polystyrene film. In the bulk experiments, green emission could be observed from the photobleached areas (photobleached with 633 nm light) when excited with 480 or 514 nm light. Similar phenomena were also observed at the single-molecule level. On the basis of the single-molecule experiments, a conversion efficiency of about 5% was estimated for the formation of emissive spectrally blue-shifted photoproducts. These green emissive photoproducts have spectral properties that resemble those of lower rylene homologues, e.g. perylene diimide or perylene monoimide. Our results indicate that the formation of blue-shifted emissive photoproducts can have implications for analyzing single-molecule FRET experiments or multiple color-labeled fluorescent systems.
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[Study on distribution characteristics and potential ecological risk of soil heavy metals in the Yellow River beach region in Kaifeng City].
Huan Jing Ke Xue
PUBLISHED: 12-03-2013
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The distributions, soil environment status and potential ecological risk of heavy metals were studied in beach soil of returning the cropland into Yellow River beach region in Kaifeng by the Nemerows and Håkansons methods. The results showed that (1) as Among the average contents of the five heavy metals Pb, Cr, Hg, As and Cd, the highest was the average content of Cr, and the lowest was the average content of Pb and Hg. In addition to Hg, the coefficients of variation of other heavy metals were relatively small, indicating that the content of heavy metals was quite different at different sites, and to some extent, relecting that Hg, As and Pb were the major elements polluting the soil, among which, Pb pollution was the pollution with universality. There was little difference in the contents of Cr and Cd from village to village the coefficient of variation was small, and the contents were below the national standard level. (2) There was significant difference in the spatial distribution of soil heavy metal elements in the upper, the middle and lower sections of the study area. The upper section was clean, the middle section was slightly polluted, and the lower section was enriched with pollutants. (3) The distribution of heavy metals in the beach region inside and outside the levees of Yellow River was closely related to the distribution of the residential regions. In the upper section of the beach region (southwest), the population was large and the contents of heavy metals were high. The contents of heavy metals were lower in the near river zone than outside the levees of Yellow River. And the heavy metal contents in the middle and lower section were higher than those outside the levees of Yellow River, while the lower section (northwest) showed a tendency of pollution enrichment. (4) In the view of the average individual potential ecological risk index of heavy metals (E(r)i), the potential ecological risk of Hg reached intense levels, and the potential ecological risk of Pbs contribution to the integrated risk was 50.5%, which was the heavy metal with highest ecological risks. Cd and Pb had a moderate ecological risk, while As and Cr had minor ecological risk. Ecological hazards of heavy metals ranked in the ascending order of Hg > Pb > As > Cd > Cr. (5) The ecological hazard of the heavy metals was ranked in the order Hg > Cd > As > Pb > Cr. Based on the potential ecological risk level corresponding to the RI values, it was shown that there was moderate potential ecological risks of heavy metals in the Yellow River beach region in Kaifeng.
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Novel TiO2/PEGDA Hybrid Hydrogel Prepared in Situ on Tumor Cells for Effective Photodynamic Therapy.
ACS Appl Mater Interfaces
PUBLISHED: 11-22-2013
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A novel inorganic/organic hybrid hydrogel system containing titanium dioxide (TiO2)/poly(ethylene glycol) double acrylates (PEGDA) was prepared by in situ photopolymerization on tumor cells for photodynamic therapy (PDT). TiO2 nanorods with diameter of ?5 nm and length of ?25 nm in this system presented dual functions, as effective photosensitizers for PDT and initiators for causing the in situ formation of hydrogel, under near-infrared (NIR) irradiation. The hybrid hydrogel retained the TiO2 around tumor cell to form a drug-loaded hydrogel shell. This resulted in a high concentration of singlet oxygen ((1)O2) under NIR irradiation, which induced apoptosis of tumor cell. Also, the hydrogel could reduce the side effects by preventing TiO2 from migrating to normal tissue. Furthermore, the TiO2 nanorods in this hydrogel shell were photochemically recyclable and could be reused in regular treatment. The outcomes of this study provide a new way to exploit multifunction of inorganic semiconductor nanomaterials for a variety of biomedical applications.
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Metal-free, single-polymer device exhibits resistive memory effect.
ACS Nano
PUBLISHED: 11-14-2013
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All-polymer, write-once-read-many times resistive memory devices have been fabricated on flexible substrates using a single polymer, poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). Spin-cast or inkjet-printed films of solvent-modified PEDOT:PSS are used as electrodes, while the unmodified or as-is PEDOT:PSS is used as the semiconducting active layer. The all-polymer devices exhibit an irreversible but stable transition from a low resistance state (ON) to a high resistance state (OFF) at low voltages caused by an electric-field-induced morphological rearrangement of PEDOT and PSS at the electrode interface. However, in the metal-PEDOT:PSS-metal devices, we have shown a metal filament formation switching the device from an initial high resistance state (OFF) to the low resistance state (ON). The all-PEDOT:PSS memory device has low write voltages (<3 V), high ON/OFF ratio (>10(3)), good retention characteristics (>10?000 s), and stability in ambient storage (>3 months).
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CXCR7 Upregulation Is Required for Early Endothelial Progenitor Cell-Mediated Endothelial Repair in Patients With Hypertension.
Hypertension
PUBLISHED: 11-04-2013
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Dysfunction of early endothelial progenitor cells (EPCs) is responsible for impaired endothelial repair capacity after arterial injury in patients with hypertension. Here, we hypothesized that diminished signaling of CXC chemokine receptor 7 (CXCR7) contributes to the reduced EPC functions, and enhanced CXCR7 expression restores the capacities of EPCs from hypertensive patients. CXCR7 expression of EPCs from hypertensive patients was significantly reduced when compared with that from healthy subjects. Meanwhile, the phosphorylation of p38 mitogen-activated protein kinase, a downstream signaling of CXCR7, was elevated, which increased cleaved caspase-3 level of EPCs. CXCR7 gene transfer augmented CXCR7 expression and decreased the phosphorylation of p38 mitogen-activated protein kinase, which was paralleled to EPC functional upregulation of in vitro adhesion, antiapoptosis activities, and in vivo re-endothelialization capacity in a nude mouse model of carotid artery injury. The enhanced in vitro and in vivo functions of EPCs were markedly inhibited by neutralizing monoclonal antibody against CXCR7, which was blocked by p38 mitogen-activated protein kinase inhibitor SB203580. Downregulation of cleaved caspase-3 level induced by CXCR7 gene transfer or SB203580 pretreatment improved EPC functions. Furthermore, we found that lercanidipine, a dihydropyridine calcium channel antagonist, enhanced CXCR7 expression and facilitated in vitro and in vivo functions of EPCs. Our study demonstrated for the first time that diminished CXCR7 signal at least partially contributes to the reduced in vitro functions and in vivo re-endothelialization capacity of EPCs from hypertensive patients. Upregulation of CXCR7 expression induced by gene transfer or lercanidipine treatment may be a novel therapeutic target for increased endothelial repair capacity in hypertension.
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Site-Specific Imaging of Elemental Steps in Dehydration of Diols on TiO2(110).
ACS Nano
PUBLISHED: 10-22-2013
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Scanning tunneling microscopy is employed to follow elemental steps in conversion of ethylene glycol and 1,3-propylene glycol on partially reduced TiO2(110) as a function of temperature. Mechanistic details about the observed processes are corroborated by density functional theory calculations. The use of these two diol reactants allows us to compare and contrast the chemistries of two functionally similar molecules with different steric constraints, thereby allowing us to understand how molecular geometry may influence the observed chemical reactivity. We find that both glycols initially adsorb on Ti sites, where a dynamic equilibrium between molecularly bound and deprotonated species is observed. As the diols start to diffuse along the Ti rows above 230 K, they irreversibly dissociate upon encountering bridging oxygen vacancies. Surprisingly, two dissociation pathways, one via O-H and the other via C-O bond scission, are observed. Theoretical calculations suggest that the differences in the C-O/O-H bond breaking processes are the result of steric factors enforced upon the diols by the second Ti-bound OH group. Above ?400 K, a new stable intermediate centered on the bridging oxygen (Ob) row is observed. Combined experimental and theoretical evidence shows that this intermediate is most likely a new dioxo species. Further annealing leads to sequential C-Ob bond cleavage and alkene desorption above ?500 K. Simulations demonstrate that the sequential C-Ob bond breaking process follows a homolytic diradical pathway, with the first C-Ob bond breaking event accompanied with a nonadiabatic electron transfer within the TiO2(110) substrate.
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Expression of Cx43-related microRNAs in patients with tetralogy of Fallot.
World J Pediatr
PUBLISHED: 10-21-2013
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Abnormal expression of connexin 43 (Cx43) has been reported to play an important role in the development of conotrunccal anomalies. However, less is known about the underlying reason for its abnormal expression. MicroRNAs (miRNAs), as an important part of gene expression regulation, have been implicated in some cardiac diseases. This study aimed to investigate the expression of Cx43 and its related miRNAs in patients with tetralogy of Fallot (TOF), and illustrate the potential role of abnormal miRNAs regulation to Cx43 expression in the pathology of TOF.
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BAFF activates Erk1/2 promoting cell proliferation and survival by Ca(2+)-CaMKII-dependent inhibition of PP2A in normal and neoplastic B-lymphoid cells.
Biochem. Pharmacol.
PUBLISHED: 10-12-2013
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B-cell activating factor (BAFF) is involved in not only the physiology of normal B cells, but also the pathophysiology of aggressive B cells related to malignant and autoimmune diseases. However, how excessive BAFF promotes aggressive B-cell proliferation and survival is not well understood. Here we show that excessive human soluble BAFF (hsBAFF) enhanced cell proliferation and survival in normal and B-lymphoid (Raji) cells, which was associated with suppression of PP2A, resulting in activation of Erk1/2. This is supported by the findings that pretreatment with U0126 or PD98059, expression of dominant negative MKK1, or overexpression of PP2A prevented hsBAFF-induced activation of Erk1/2 and cell proliferation/viability in the cells. It appears that hsBAFF-mediated PP2A-Erk1/2 pathway and B-cell proliferation/viability was Ca(2+)-dependent, as pretreatment with BAPTA/AM, EGTA or 2-APB significantly attenuated these events. Furthermore, we found that inhibiting CaMKII with KN93 or silencing CaMKII also attenuated hsBAFF-mediated PP2A-Erk1/2 signaling and B-cell proliferation/viability. The results indicate that BAFF activates Erk1/2, in part through Ca(2+)-CaMKII-dependent inhibition of PP2A, increasing cell proliferation/viability in normal and neoplastic B-lymphoid cells. Our data suggest that inhibitors of CaMKII and Erk1/2, activator of PP2A or manipulation of intracellular Ca(2+) may be exploited for prevention of excessive BAFF-induced aggressive B-cell malignancies and autoimmune diseases.
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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.

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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.