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Find video protocols related to scientific articles indexed in Pubmed.
Molecular insight into nanoscale water films dewetting on modified silica surfaces.
Phys Chem Chem Phys
PUBLISHED: 11-20-2014
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In this work, molecular dynamics simulations are adopted to investigate the microscopic dewetting mechanism of nanoscale water films on methylated silica surfaces. The simulation results show that the dewetting process is divided into two stages: the appearance of dry patches and the quick contraction of the water film. First, the appearance of dry patches is due to the fluctuation in the film thickness originating from capillary wave instability. Second, for the fast contraction of water film, the unsaturated electrostatic and hydrogen bond interactions among water molecules are the driving forces, which induce the quick contraction of the water film. Finally, the effect of film thickness on water films dewetting is studied. Research results suggest that upon increasing the water film thickness from 6 to 8 Å, the final dewetting patterns experience separate droplets and striation-shaped structures, respectively. But upon further increasing the water film thickness, the water film is stable and there are no dry patches. The microscopic dewetting behaviors of water films on methylated silica surfaces discussed here are helpful in understanding many phenomena in scientific and industrial processes better.
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High-rate amorphous SnO2 nanomembrane anodes for Li-ion batteries with a long cycling life.
Nanoscale
PUBLISHED: 11-20-2014
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Amorphous SnO2 nanomembranes as anodes for lithium ion batteries demonstrate a long cycling life of 1000 cycles at 1600 mA g(-1) with a high reversible capacity of 854 mA h g(-1) and high rate capability up to 40 A g(-1). The superior performance is because of the structural features of the amorphous SnO2 nanomembranes. The nanoscale thickness provides considerably reduced diffusion paths for Li(+). The amorphous structure can accommodate the strain of lithiation/delithiation, especially during the initial lithiation. More importantly, the mechanical feature of deformation can buffer the strain of repeated lithiation/delithiation, thus putting off pulverization. In addition, the two-dimensional transport pathways in between nanomembranes make the pseudo-capacitance more prominent. The encouraging results demonstrate the significant potential of nanomembranes for high power batteries.
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Kinetics and interfacial thermodynamics of the pH-related sorption of tetrabromobisphenol A onto multi-walled carbon nanotubes.
ACS Appl Mater Interfaces
PUBLISHED: 11-18-2014
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Surface functionalization of multi-walled carbon nanotubes (MWCNTs) was performed using mixed acid and ethylenediamine. The materials were characterized by electron microscope, X-ray diffraction, Raman spectra, Fourier transform infrared, N2 adsorption-desorption and X-ray photoelectron spectroscopy. The pH-dependent sorption of tetrabromobisphenol A (TBBPA) onto raw and functionalized MWCNTs was investigated. A decrease in TBBPA uptake was found to be dependent on the adsorptive pKa in alkaline conditions. Two types of MWCNTs exhibited rapid binding kinetics for TBBPA sorption within 20 min. The kinetics of TBBPA sorption onto MWCNTs were analyzed using a pseudo-second-order model, an intra-particle diffusion model and Boyd model. The results showed that TBBPA sorption on MWCNTs and N-MWCNTs could be well described by the pseudo-second-order model, and the external diffusion (boundary layer diffusion) was the rate-limiting step. The extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory was applied to calculate interfacial free energies and to explain the sorption characteristics between the sorbent and solute. This analysis revealed that hydrophobic attractive interactions (i.e., interfacial AB interactions) were dominant in TBBPA sorption onto MWCNTs.
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Wavefront-correction for nearly diffraction-limited focusing of dual-color laser beams to high intensities.
Opt Express
PUBLISHED: 11-18-2014
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We demonstrate wavefront correction of terawatt-peak-power laser beams at two distinct and well-separated wavelengths. Simultaneous near diffraction-limited focusability is achieved for both the fundamental (800 nm) and second harmonic (400 nm) of Ti:sapphire-amplified laser light. By comparing the relative effectiveness of various correction loops, the optimal ones are found. Simultaneous correction of both beams of different color relies on the linear proportionality between their wavefront aberrations. This method can enable two-color experiments at relativistic intensities.
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[Clinical characteristics and prognosis comparison of Chinese non ST-segment elevation acute coronary syndrome patients in two different time periods].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 11-13-2014
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To compare the clinical characteristics, treatment methods and outcomes in Chinese non ST-segment elevation acute coronary syndrome (NSTE-ACS) patients from two large clinical trials in different time periods.
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Analysis of 90 cases of antithyroid drug-induced severe hepatotoxicity over 13 years in China.
Thyroid
PUBLISHED: 11-11-2014
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Background: Antithyroid drug (ATD)-induced severe hepatotoxicity is a rare but serious complication of ATD therapy. The characteristics of severe hepatotoxicity have been reported in only a small number of patients. Method: We studied 90 patients with ATD-induced severe hepatotoxicity presenting during a 13 year period (2000-2013) who were about to undergo nuclear medicine therapy with 131I from a sample of 8864 patients with hyperthyroidism, and we evaluated the outcomes. Results: The mean age of the patients with ATD-induced severe hepatotoxicity was 41.6±12.5 years (mean±SD), and the female to male ratio was 2.2:1. The methimazole (MMI) dose given at the onset was 19.1±7.4 mg/d. The propylthiouracil (PTU) dose given at the onset was 212.8±105.0 mg/d. ATD-induced severe hepatotoxicity occurred in 63.3%, 75.6%, and 81.1% of patients within 4, 8, and 12 weeks of the onset of ATD therapy, respectively. The types of severe hepatotoxicity did not differ between the MMI and PTU groups (p=0.188). The frequency of the cholestatic type in the MMI group (35.3%, 18/51) was higher than that in the PTU group (17.9%, 7/39), but these frequencies were not significantly different (p=0.069). The patients who took 131I received an average dose of 279.1±86.1 MBq (n=84). Therapy was successful in 60 of the 67 patients (89.6%). The success rate was equivalent (p=0.696) between the groups receiving MMI (91.7%, 33/36) and PTU (87.1%, 27/31). Conclusions: Severe hepatotoxicity tends to occur within the first three months after the onset of ATD therapy. The type of ATD-induced severe hepatotoxicity did not differ between the MMI and PTU groups. 131I therapy is an effective treatment approach for patients with ATD-induced severe hepatotoxicity.
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Isoflurane Protects the Myocardium Against Ischemic Injury via the Preservation of Mitochondrial Respiration and Its Supramolecular Organization.
Anesth. Analg.
PUBLISHED: 11-11-2014
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Isoflurane has been demonstrated to limit myocardial ischemic injury. This effect is hypothesized to be mediated in part via effects on mitochondria. We investigated the hypothesis that isoflurane maintains mitochondrial respiratory chain functionality, in turn limiting mitochondrial damage and mitochondrial membrane disintegration during myocardial ischemic injury.
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Molecular pathology analyses of two fatal human infections of avian influenza A(H7N9) virus.
J. Clin. Pathol.
PUBLISHED: 11-08-2014
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To investigate the histopathological manifestations of two fatal cases of H7N9 influenza A virus infection.
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Energy Storage in Ferroelectric Polymer Nanocomposites Filled with Core-shell Structured Polymer@BaTiO3 Nanoparticles: Understanding the Role of Polymer Shells in the Interfacial Regions.
ACS Appl Mater Interfaces
PUBLISHED: 11-04-2014
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Interfacial region plays a critical role in determining the electrical properties and energy storage density of dielectric polymer nanocomposites. However, we still know a little about the effects of electrical properties of the interfacial regions on the electrical properties and energy storage of dielectric polymer nanocomposites. In this work, three types of core-shell structured polymer@BaTiO3 nanoparticles with polymer shells having different electrical properties were used as fillers to prepare ferroelectric polymer nanocomposites. All the polymer@BaTiO3 nanoparticles were prepared by surface initiated RAFT polymerization and the polymer shells were controlled to have the same thickness. The morphology, crystal structure, frequency-dependent dielectric properties, breakdown strength, leakage currents, energy storage capability and energy storage efficiency of the polymer nanocomposites were investigated. On the other hand, the pure polymers having the same molecular structure with the shells of polymer@BaTiO3 nanoparticles were also prepared by RAFT polymerization and their electrical properties were provided. Our results show that, to achieve nanocomposites with high discharged energy density, the core-shell nanoparticles filler should simultaneously have high dielectric constant and low electrical conductivity. The breakdown strength of the nanocomposites is highly affected by the dielectric constant of the polymer shells and a low dielectric constant with a low electrical conductivity tends to result in high breakdown strength.
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The Diagnostic Utility of Combination of HMGA2 and IMP3 qRT-PCR Testing in Thyroid Neoplasms.
Appl. Immunohistochem. Mol. Morphol.
PUBLISHED: 10-31-2014
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The diagnosis of malignant thyroid tumors in some cytologic and histologic specimens remains challenging. High-mobility group A2 (HMGA2) expression and insulin-like growth factor II mRNA-binding protein-3 (IMP3) expression were evaluated by relative quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The aim of this study was to evaluate whether the combination of HMGA2 and IMP3 qRT-PCR was diagnostically useful in differentiating benign from malignant thyroid neoplasms. Fine-needle aspiration (FNA) specimens from 120 patients including 56 benign lesions and 64 carcinomas were used. The available 80 corresponding formalin-fixed paraffin-embedded (FFPE) thyroid tissues from 66 patients were also included in this study. HMGA2 and IMP3 expression levels were detected by qRT-PCR and reported as relative fold change after normalizing with a calibrator. The diagnostic utilities of HMGA2 and IMP3 qRT-PCR tests were evaluated individually and in combination. In FNA specimens, HMGA2 and IMP3 expression was consistently higher in thyroid malignancies compared with benign lesions in all subgroups except in Hürthle cell tumors. After exclusion of Hürthle cell tumors, the sensitivity was 90.2% for HMGA2, 88.2% for IMP3, and 98% for HMGA2+IMP3; the specificity was 97.1% for HMGA2, 79.4% for IMP3, and 79.4% for HMGA+IMP3. qRT-PCR data showed similar results in FFPE tissues: the sensitivity was 84.2% for HMGA2, 85.7% for IMP3, and 94.7% for HMGA2+IMP3; the specificity was 96.9% for HMGA2, 91.2% for IMP3, and 90.6% for HMGA2+IMP3. qRT-PCR data were concordant between FNA and FFPE samples for HMGA2 (97.4%) and IMP3 (96.9%). The results indicate that HMGA2 qRT-PCR with high specificity may be a useful ancillary technique to assist in the classification of difficult thyroid specimens, excluding Hürthle cell tumors. The HMGA2 and IMP3 qRT-PCR combination model with increased sensitivity and negative predictive value (96.4%) may be useful in screening thyroid cytology specimens.
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Exceptionally Stiff Two-Dimensional Molecular Crystal by Substrate-Confinement.
ACS Nano
PUBLISHED: 10-28-2014
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We demonstrated an approach to effectively apply in-plane pressures to molecular layers by utilizing the substrate confinement effect. The compressed crystal structure and mechanical behaviors of carbon monoxide (CO) monolayer subjected to the confinement of Cu(100) substrate were jointly investigated by low temperature scanning tunneling microscopy experiments and first-principles density functional theory calculations. By increasing molecular coverage, an exceptionally large Young's modulus of 33 GPa was derived for the constrained CO monolayer film. This extreme in-plane pressure leads to site-specific tilting geometries, polymeric-like electronic states, and vibrational behaviors of CO molecules in the compressed phases. These results provide an extended understanding of the physical and chemical properties of intermolecular interactions in this fundamental system.
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[Decolorization of chitin from Catharsius molossus discards].
Zhong Yao Cai
PUBLISHED: 10-28-2014
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Decolorization of crude chitin from Catharsius molossus was studied in order to prepare chitosan with white color and high viscosity.
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An Evolutionary Algorithm with Double-Level Archives for Multiobjective Optimization.
IEEE Trans Cybern
PUBLISHED: 10-25-2014
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Existing multiobjective evolutionary algorithms (MOEAs) tackle a multiobjective problem either as a whole or as several decomposed single-objective sub-problems. Though the problem decomposition approach generally converges faster through optimizing all the sub-problems simultaneously, there are two issues not fully addressed, i.e., distribution of solutions often depends on a priori problem decomposition, and the lack of population diversity among sub-problems. In this paper, a MOEA with double-level archives is developed. The algorithm takes advantages of both the multiobjective-problemlevel and the sub-problem-level approaches by introducing two types of archives, i.e., the global archive and the sub-archive. In each generation, self-reproduction with the global archive and cross-reproduction between the global archive and sub-archives both breed new individuals. The global archive and sub-archives communicate through cross-reproduction, and are updated using the reproduced individuals. Such a framework thus retains fast convergence, and at the same time handles solution distribution along Pareto front (PF) with scalability. To test the performance of the proposed algorithm, experiments are conducted on both the widely used benchmarks and a set of truly disconnected problems. The results verify that, compared with state-of-the-art MOEAs, the proposed algorithm offers competitive advantages in distance to the PF, solution coverage, and search speed.
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[Catheter aspiration alone or combined with thrombolysis in the treatment of superior mesenteric artery embolism].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 10-25-2014
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To investigate the efficacy of catheter aspiration or combined with thrombolysis in the treatment of superior mesenteric artery embolism(SMAE).
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Crystal Structure and Optical Properties of the [Ag62S12(SBu(t))32](2+) Nanocluster with a Complete Face-Centered Cubic Kernel.
J. Am. Chem. Soc.
PUBLISHED: 10-24-2014
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The crystal structure of the [Ag62S12(SBu(t))32](2+) nanocluster (denoted as NC-I) has been successfully determined, and it shows a complete face-centered-cubic (FCC) Ag14 core structure with a Ag48(SBu(t))32 shell configuration interconnected by 12 sulfide ions, which is similar to the [Ag62S13(SBu(t))32](4+) structure (denoted as NC-II for short) reported by Wang. Interestingly, NC-I exhibits prominent differences in the optical properties in comparison with the case of the NC-II nanocluster. We employed femtosecond transient absorption spectroscopy to further identify the differences between the two nanoclusters. The results show that the quenching of photoluminescence in NC-I in comparison to that of NC-II is caused by the free valence electrons, which dramatically change the ligand to metal charge transfer (LMCT, S 3p ? Ag 5s). To get further insight into these, we carried out time-dependent density functional theory (TDDFT) calculations on the electronic structure and optical absorption spectra of NC-I and NC-II. These findings offer a new insight into the structure and property evolution of silver cluster materials.
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[Treatment of combined hyperlipidemia patients by jiangzhi tongluo soft capsule combined atorvastatin calcium tablet: a clinical study].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 10-23-2014
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To evaluate the efficacy and safety of using Jiangzhi Tongluo Soft Capsule (JTSC) combined with Atorvastatin Calcium Tablet (ACT) or ACT alone in treatment of combined hyperlipidemia.
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Metal-free aminoamidiniumation employing N-iodosuccinimide: facile syntheses of bicyclic imidazolidiniums and cyclic vicinal diamines.
Chem. Commun. (Camb.)
PUBLISHED: 10-21-2014
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NIS-mediated aminoamidiniumation has been developed for the syntheses of bicyclic imidazolidinium salts, which could be readily converted into cyclic vicinal diamines.
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[Analysis of high risk factors for patient death and its clinical characteristics on pregnancy associated with pulmonary arterial hypertension].
Zhonghua Fu Chan Ke Za Zhi
PUBLISHED: 10-21-2014
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Study of pulmonary hypertension (PAH) during pregnancy has characteristics of the high risk factors for patient death and its clinical characteristics.
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Crystal structure of Au25(SePh)18 nanoclusters and insights into their electronic, optical and catalytic properties.
Nanoscale
PUBLISHED: 10-16-2014
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The crystal structure of selenolate-capped Au25(SePh)18(-) nanoclusters has been unambiguously determined for the first time, and provides a solid basis for a deeper understanding of the structure-property relationships. The selenolate-capped Au25 cluster shows noticeable differences from the previously reported Au25(SCH2CH2Ph)18(-) counterpart, albeit both share the icosahedral Au13 core and semi-ring Au2(SeR)3 or Au2(SR)3 motifs. Distinct differences in the electronic structure and optical, catalytic and electrochemical properties are revealed by the coupling experiments with density functional theory (TD-DFT) calculations. Overall, the successful determination of the Au25(SePh)18(-) structure removes any ambiguity about its structure, and comparison with the thiolated Au25 counterpart helps us to further understand how the ligands affect the properties of the nanocluster.
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Differential Evolution with an Evolution Path: A DEEP Evolutionary Algorithm.
IEEE Trans Cybern
PUBLISHED: 10-15-2014
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Utilizing cumulative correlation information already existing in an evolutionary process, this paper proposes a predictive approach to the reproduction mechanism of new individuals for differential evolution (DE) algorithms. DE uses a distributed model (DM) to generate new individuals, which is relatively explorative, whilst evolution strategy (ES) uses a centralized model (CM) to generate offspring, which through adaptation retains a convergence momentum. This paper adopts a key feature in the CM of a covariance matrix adaptation ES, the cumulatively learned evolution path (EP), to formulate a new evolutionary algorithm (EA) framework, termed DEEP, standing for DE with an EP. Without mechanistically combining two CM and DM based algorithms together, the DEEP framework offers advantages of both a DM and a CM and hence substantially enhances performance. Under this architecture, a self-adaptation mechanism can be built inherently in a DEEP algorithm, easing the task of predetermining algorithm control parameters. Two DEEP variants are developed and illustrated in the paper. Experiments on the CEC'13 test suites and two practical problems demonstrate that the DEEP algorithms offer promising results, compared with the original DEs and other relevant state-of-the-art EAs.
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Tumor hypoxia enhances Non-Small Cell Lung Cancer metastasis by selectively promoting macrophage M2 polarization through the activation of ERK signaling.
Oncotarget
PUBLISHED: 10-15-2014
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Hypoxia is a common phenomenon occurring in the majority of human tumors and has been proved to play an important role in tumor progression. However, it remains unclear that whether the action of hypoxia on macrophages is a main driving force of hypoxia-mediated aggressive tumor behaviors. In the present study, we observe that high density of M2 macrophages is associated with metastasis in adenocarcinoma Non-Small Cell Lung Cancer (NSCLC) patients. By applying the in vivo hypoxia model, the results suggest that intermittent hypoxia significantly promotes the metastasis of Lewis lung carcinoma (LLC), accompanied with more CD209+ macrophages infiltrated in primary tumor tissue. More intriguingly, by skewing macrophages polarization away from the M1- to a tumor-promoting M2-like phenotype, hypoxia and IL-6 cooperate to enhance the LLC metastasis both in vitro and in vivo. In addition, we also demonstrate that skewing of macrophage M2 polarization by hypoxia relies substantially on activation of ERK signaling. Collectively, these observations unveil a novel tumor hypoxia concept involving the macrophage phenotype shift and provide direct evidence for lung cancer intervention through modulating the phenotype of macrophages.
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Comparison of the tada formula with software slicer: precise and low-cost method for volume assessment of intracerebral hematoma.
Stroke
PUBLISHED: 10-14-2014
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The Tada (ABC/2) formula has been used widely for volume assessment of intracerebral hematoma. However, the formula is crude for irregularly shaped hematoma. We aimed to compare the accuracy of the ABC/2 formula with open source software Slicer.
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Comparative Gene Identification-58 (CGI-58) Promotes Autophagy as a Putative Lysophosphatidylglycerol Acyltransferase.
J. Biol. Chem.
PUBLISHED: 10-14-2014
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CGI-58 is a lipid droplet-associated protein when mutated causes Chanarin-Dorfman syndrome in humans, which is characterized by excessive storage of triglyceride (TAG) in various tissues. However, the molecular mechanisms underlying the defect remain elusive. CGI-58 was previously reported to catalyze the resynthesis of phosphatidic acid (PA) as a lysophosphatidic acid acyltransferase. In addition to TAG, PA is also used a substrate for the synthesis of various mitochondrial phospholipids. In this report, we investigated the propensity of CGI-58 in the remodeling of various phospholipids. We found that the recombinant CGI-58 overexpressed in mammalian cells or purified from Sf9 insect cells catalyzed efficiently the reacylation of lysophosphatidylglycerol to phosphatidylglycerol (PG), which requires acyl-CoA as the acyl donor. In contrast, the recombinant CGI-58 was devoid of acyltransferase activity towards other lysophospholipids. Accordingly, overexpression and knockdown of CGI-58 adversely affected the endogenous PG level in C2C12 cells. PG is a substrate for the synthesis of cardiolipin which is required for mitochondrial oxidative phosphorylation and mitophagy. Consequently, overexpression and knockdown of CGI-58 adversely affected autophagy and mitophagy in C2C12 cells. In support for a key role of CGI-58 in mitophagy, overexpression of CGI-58 significantly stimulated mitochondrial fission and translocation of PINK1 to mitochondria, key steps involved in mitophagy. Furthermore, overexpression of CGI-58 promoted mitophagic initiation through activation of AMPK and inhibition of mTORC1 signaling, the positive and negative regulators of autophagy, respectively. Together, these findings identified novel molecular mechanisms by which CGI-58 regulates lipid homeostasis, since defective autophagy is implicated in dyslipidemia and fatty liver diseases.
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Polypeptide-Functionalized NaYF4:Yb(3+),Er(3+) Nanoparticles: Red-Emission Biomarkers for High Quality Bioimaging Using a 915 nm Laser.
ACS Appl Mater Interfaces
PUBLISHED: 10-14-2014
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We prepared poly-l-aspartic acid (PASP) functionalized NaYF4:Yb(3+),Er(3+) upconversion nanoparticles (UCNP-PASP). These nanoparticles can give red upconversion emission under excitation at 915 nm, whose wavelength of emission and excitation is located in the optical window of biological tissue. Dynamic laser scatting and zeta potentials of UCNP-PASP were used to study their stabilities in different aqueous solution. To understand the mechanism of the red emission of UCNP-PASP, photoluminescence spectra of samples were recorded before and after modification with PASP, poly acrylic acid (PAA), and poly(ether imide) (PEI) ligands under excitation at 915 and 980 nm, respectively. The cytotoxicity of the UCNP-PASP was also examined on a A549 cell and KB cell by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay. Moreover, the PASP-functionalized UCNP was employed as a potential biomarker for in vitro and in vivo experiments of upconversion luminescence imaging.
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[Application of methylation-specific multiplex ligation-dependent probe amplification for the study of DNA methylation in placenta tissues].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 10-10-2014
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To study the feasibility of using methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) for the detection of DNA methylation in placenta tissue.
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Colivelin ameliorates amyloid ? peptide-induced impairments in spatial memory, synaptic plasticity, and calcium homeostasis in rats.
Hippocampus
PUBLISHED: 10-09-2014
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Amyloid ? peptide (A?) has been thought to be neurotoxic and responsible for the impairment of learning and memory in Alzheimer's disease (AD). Humanin (HN), a 24 amino acid polypeptide first identified from the unaffected occipital lobe of an AD patient, is believed to be neuroprotective against the AD-related neurotoxicity. In this study, we investigated the neuroprotective effects of Colivelin (CLN), a novel HN derivative, against A? by using behavioral test, in vivo electrophysiological recording, and intracellular calcium imaging. Our results showed that intrahippocampal injection of CLN (0.2 nmol) effectively prevented A?25-35 (4 nmol)-induced deficits in spatial learning and memory of rats in Morris water maze test; the suppression of in vivo hippocampal long term potentiation (LTP) by A?25-35 was nearly completely prevented by CLN; in addition, CLN pretreatment also effectively inhibited A?25-35-induced calcium overload in primary cultured hippocampal neurons. These results indicate that CLN has significant neuroprotective properties against A?, and CLN may holds great promise for the treatment and prevention of AD. © 2014 Wiley Periodicals, Inc.
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[Determination of plasma concentration of five phenolic acid by LC-MS/MS and study of pharmacokinetics in rats after Mailuoning injection].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-07-2014
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To establish a LC-MS/MS method for quantification of chlorogenic acid, caffeic acid, 3,4-DCQA, ferulic acid and cinnamic acid in rats plasma and study its pharmacokinetics after administration of Mailuoning injection at a single dose to rats. Plasma samples were acidified with hydrochloric acid and extracted with ethyl acetate. The analytes were determined by LC-MS-MS using a ZOBAX SB C18 column with a mobile phase of methanol-water (containing 2 mmol x L(-1) ammonium acetic) (60:40)at a flow rate of 0.5 mL x min(-1) and detected using ESI with negative ionization mode. Ions monitored in the multiple reaction monitoring (MRM) mode were m/z 353.1/191.0 [M-H]- for chlorogenic acid, m/z 178.9/134.9 [M-H]- for caffeic acid, m/z 515.2/353.0 [M-H]-for 3,4-DCQA, m/z 193.0/133.9 [M-H]-for ferulic acid, m/z 146.9/102.9 [M-H]- for cinnamic acid and m/z 246.0/125.8 [M-H]- for tinidazole (IS). After administration of Mailuoning injection at a single dose to eight Sprague-Dawley rats, the concentrations of chlorogenic acid, caffeic acid, 3,4-DCQA, ferulic acid and cinnamic acid in plasma were determined by LC-MS/MS method. The main pharmacokinetics parameters of measured data were caluculated by using DASver 1.0 software. The linear concentration ranges of the calibration curves for chlorogenic acid, caffeic acid, 3,4-DCQA and cinnamic acid were 2.006-1,027 microg x L(-1) (r = 0.999 6), 1.953-1,000 microg x L(-1) (r = 0.999 7), 28.51-1.459 x 10(4) microg x L(-1) (r = 0.998 9), 1.836-940.0, g x L(-1) (r = 0.997 7) and 4.780-2,447 microg x L(-1) (r = 0.998 6) respectively. The inner and inter-days relative standard deviations were both less than 5.0%, indicating legitimate precise and accuracy to the requirement of biological sample analysis. For chlorogenic acid, the pharmacokinetic parameter t1/2, AUC0-t, and CL were (49.78 +/- 12.81) min, (123.55 +/- 14.82) mg x min x L(-1) and (0.004 3 +/- 0.000 5) L x min(-1), respectively. For caffeic acid, the pharmacokinetic parameter t1/2, AUC0-t, and CL were (36.65 +/- 10.59) min, (91.67 +/- 11.77) mg x min L(-1) and (0.005 7 +/- 0.000 7) L x min(-1), respectively. For 3,4-DCQA, the pharmacokinetic parameter t1/2, AUC0-t, and CL were (50.08 +/- 13.78) min, (278.34 +/- 31.82) mg x min x L-1 and (0.001 6 +/- 0.000 2) L x min(-1), respectively. For ferulic acid, the pharmacokinetic parameter t1/2, AUC0-t, and CL were (51.39 +/- 15.52) min, (34.72 +/- 4.67) mg x min x L(-1) and (0.000 4 +/- 0.0001) L x min(-1), respectively. For cinnamic acid, the pharmacokinetic parameter t1/2, AUCo-t, and CL were (74.42 +/- 18.32) min, (34.63 +/- 4.82) mg x min x L(-1) and (0.007 7 +/- 0.001 1) L x min-', respectively. The assay method is proved to be sensitive, accurate and convenient. It can be applied to the pharmacokinetic study of chlorogenic acid, caffeic acid, 3,4-DCQA, ferulic acid and cinnamic acid.
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Pin1 is Overexpressed and Correlates with Poor Prognosis in Gastric Cancer.
Cell Biochem. Biophys.
PUBLISHED: 10-05-2014
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The prolyl isomerase Pin1, which isomerizes the p-Ser/Thr-Pro peptide bonds and effects conformational and functional changes of the bound proteins, has been identified as a regulator of phosphorylation signaling in several diseases including cancer. The aim of this study is to determine the expression status of Pin1 in gastric cancer, its relationship between clinicopathologic features and patients' outcome. The mRNA levels of Pin1 in human normal and gastric cancer tissues were analyzed using the datasets from the publicly available Oncomine database ( www.oncomine.org ). Pin1 protein levels in human gastric cancer cells and tissues were analyzed by Western blot and immunohistochemistry staining, respectively. The Pin1 protein expression levels and its clinicopathologic correlations were investigated using tumor tissue microarray including 182 cases of human gastric cancer samples with survival information. Pin1 mRNA expression was found to be overexpressed in gastric cancer by using several datasets of Oncomine database analyzing. Pin1 protein expression is higher in 10 gastric cancer cell lines than that in normal gastric epithelial cell line GES-1. Pin1 positive expression was observed in 109 of 182 (59.9 %) gastric cancer samples and in 55 of 182 (30.2 %) normal gastric tissues (P < 0.001). Correlation analysis showed that high expression of Pin1 was significantly associated with pT (P = 0.017), pN (P = 0.043), TNM staging (P = 0.027), Lauren's classification (P < 0.001), as well as shorter overall survival in gastric cancer patients (29 mos vs. 47 mos. P = 0.048). Moreover, Pin1 expression, pT, and differentiation were independent prognostic factors of gastric cancer in Cox regression analysis. Pin1 is overexpressed in gastric cancer and correlates with clinicopathologic features, which might predict poor prognosis of gastric cancer patients.
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Unusual, photo-induced self-assembly of azobenzene-containing amphiphiles.
Soft Matter
PUBLISHED: 10-04-2014
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Stimuli-responsive self-assembly is playing an increasingly important role in emerging applications, ranging from smart materials to biosensors. However, obtaining essential information for further development, such as molecular arrangement and interaction, is still experimentally challenging. A molecular-level understanding of the stimuli-responsive self-assembly is needed. Azobenzene-containing (azo-containing) amphiphiles organize into photo-responsive assemblies because of the cis-trans isomerization triggered by the irradiation of ultraviolet (UV) and visible light. In this study, we applied a coarse grained (CG) molecular dynamics (MD) simulation, with the necessary potential parameters fitted from theoretical calculation data, to study the photo-induced self-assembly of 4,4'-bis(hydroxymethyl)-azobenzene (AzoCO), a simple azo-containing amphiphile. An unusual "chaotic micelle" and "monolayer phase" were obtained with cis- and trans-AzoCO molecules, respectively. The structural information and formation mechanism were studied. The "chaotic micelle" possesses a chaotic but not a pure hydrophobic interior as commonly understood. Through comparative simulations, we found that the azo (-N[double bond, length as m-dash]N-) group of azobenzene plays a crucial role in the formation of the "chaotic micelle". The "monolayer phase" is arranged by abreast rod-like trans-AzoCO molecules; the axial symmetry of the trans-AzoCO molecule drives the formation of this structure. The novel "chaotic micelle" and "monolayer phase" have potential applications in nanotechnology and bioengineering. This work is expected to trigger further studies on stimuli-responsive phenomena and materials.
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Ultrafast Carrier Thermalization and Cooling Dynamics in Few-Layer MoS2.
ACS Nano
PUBLISHED: 10-02-2014
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Femtosecond optical pump-probe spectroscopy with 10 fs visible pulses is employed to elucidate the ultrafast carrier dynamics of few-layer MoS2. A nonthermal carrier distribution is observed immediately following the photoexcitation of the A and B excitonic transitions by the ultrashort, broadband laser pulse. Carrier thermalization occurs within 20 fs and proceeds via both carrier-carrier and carrier-phonon scattering, as evidenced by the observed dependence of the thermalization time on the carrier density and the sample temperature. The n(-0.37±0.03) scaling of the thermalization time with carrier density suggests that equilibration of the nonthermal carrier distribution occurs via non-Markovian quantum kinetics. Subsequent cooling of the hot Fermi-Dirac carrier distribution occurs on the ?0.6 ps time scale via carrier-phonon scattering. Temperature- and fluence-dependence studies reveal the involvement of hot phonons in the carrier cooling process. Nonadiabatic ab initio molecular dynamics simulations, which predict carrier-carrier and carrier-phonon scattering time scales of 40 fs and 0.5 ps, respectively, lend support to the assignment of the observed carrier dynamics.
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Diagnostic value of surfactant protein-a in severe acute pancreatitis-induced acute respiratory distress syndrome.
Med. Sci. Monit.
PUBLISHED: 09-27-2014
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The complexity of multiple-item criteria in acute respiratory distress syndrome (ARDS) often causes inconvenience for physicians in the management of patients with severe acute pancreatitis (SAP). We evaluated whether serum SP-A levels in the presence of diffuse alveolar damage (DAD) can be qualitatively assessed for diagnosis of SAP-induced ARDS.
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Iron pyrite thin film counter electrodes for dye-sensitized solar cells: high efficiency for iodine and cobalt redox electrolyte cells.
ACS Nano
PUBLISHED: 09-26-2014
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Iron pyrite has been the material of interest in the solar community due to its optical properties and abundance. However, the progress is marred due to the lack of control on the surface and intrinsic chemistry of pyrite. In this report, we show iron pyrite as an efficient counter electrode (CE) material alternative to the conventional Pt and poly(3,4-ethylenedioxythiophene (PEDOT) CEs in dye-sensitized solar cells (DSSCs). Pyrite film CEs prepared by spray pyrolysis are utilized in I3(-)/I(-) and Co(III)/Co(II) electrolyte-mediated DSSCs. From cyclic voltammetry and impedance spectroscopy studies, the catalytic activity is found to be comparable with that of Pt and PEDOT in I3(-)/I(-) and Co(III)/Co(II) electrolyte, respectively. With the I3(-)/I(-) electrolyte, photoconversion efficiency is found to be 8.0% for the pyrite CE and 7.5% for Pt, whereas with Co(III)/Co(II) redox DSSCs, efficiency is found to be the same for both pyrite and PEDOT (6.3%). The excellent performance of the pyrite CE in both the systems makes it a distinctive choice among the various CE materials studied.
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[Expression levels of co-inhibitory molecules CTLA-4, LAG-3, PD-1 and CD39 on CD4? T cells correlate with progression of non-small cell lung cancer].
Zhonghua Zhong Liu Za Zhi
PUBLISHED: 09-23-2014
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To detect the expression levels of co-inhibitory molecules, including CTLA-4, LAG-3, PD-1 and CD39, on CD4? T cells in peripheral blood or tumor tissues from NSCLC patients and to investigate their potential internal relationships with the progression of NSCLC.
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Cholesterol Esters (CE) Derived From Hepatic Sterol O-Acyltransferase 2 (SOAT2) Are Associated With More Atherosclerosis Than CE From Intestinal SOAT2.
Circ. Res.
PUBLISHED: 09-19-2014
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Cholesterol esters (CE), especially cholesterol oleate, generated by hepatic and intestinal sterol O-acyltransferase 2 (SOAT2) play a critical role in cholesterol homeostasis. However, it is unknown whether the contribution of intestine-derived CE from SOAT2 would have similar effects in promoting atherosclerosis progression as for liver-derived CE.
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Big data in chemical toxicity research: the use of high-throughput screening assays to identify potential toxicants.
Chem. Res. Toxicol.
PUBLISHED: 09-16-2014
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High-throughput screening (HTS) assays that measure the in vitro toxicity of environmental compounds have been widely applied as an alternative to in vivo animal tests of chemical toxicity. Current HTS studies provide the community with rich toxicology information that has the potential to be integrated into toxicity research. The available in vitro toxicity data is updated daily in structured formats (e.g., deposited into PubChem and other data-sharing web portals) or in an unstructured way (papers, laboratory reports, toxicity Web site updates, etc.). The information derived from the current toxicity data is so large and complex that it becomes difficult to process using available database management tools or traditional data processing applications. For this reason, it is necessary to develop a big data approach when conducting modern chemical toxicity research. In vitro data for a compound, obtained from meaningful bioassays, can be viewed as a response profile that gives detailed information about the compound's ability to affect relevant biological proteins/receptors. This information is critical for the evaluation of complex bioactivities (e.g., animal toxicities) and grows rapidly as big data in toxicology communities. This review focuses mainly on the existing structured in vitro data (e.g., PubChem data sets) as response profiles for compounds of environmental interest (e.g., potential human/animal toxicants). Potential modeling and mining tools to use the current big data pool in chemical toxicity research are also described.
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[Spectra modulated surface plasmon resonance sensor based on side polished multi-mode optical fiber].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 09-12-2014
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Surface plasmon resonance, which utilizes the resonance of optical evanescent wave with the metal surface plasmon wave, has been developed into a high sensitivity, rapid, label-less measurement method for chemical and biological analysis. In order to improve the spectral sensitivity in refractive index for a side polished fiber surface plasmon resonance sensor, the whole cladding layer and part of core of a multimode fiber was polished off. Additionally, an extra chrome layer with relatively high refractive index was coated on the polished zone before a gold film. The results showed that the sensor can measure the refractive index range from 1.333 to 1. 431 RIU, with the average spectral sensitivity of 4.11 x 10(3) nm RIU(-1), which is better than the reported results. Especially, in the refractive index range of 1. 417 1. 431 RIU, the sensitivity reaches to 1.09 x 10(4) nm RIU(-1). The minimum resolution of approximately 3.6 x 10(-5) RIU was estimated by a combination analysis with the sensor sensitivity and stability. The superiorities possessed by the proposed sensor in high sensitivity, wide detection range, small size and good stability and reproducibility, etc., make it a good candidate for food testing, environmental monitoring, biomedical testing and other related fields.
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Comparison of Three Luminescent Immunoassays for Hepatitis B Virus Surface Antigen Quantification during the Natural History of Chronic Hepatitis B Virus Infection.
Clin. Vaccine Immunol.
PUBLISHED: 09-10-2014
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Hepatitis B surface antigen (HBsAg) quantification has garnered attention because of its high predictive value in determining treatment responses. The HBsAg quantification assays, such as Architect and Elecsys, are commercially available, and more assays are in development. We aimed to compare the results of the Architect and Elecsys assays with those of a new assay, WTultra. The WTultra HBsAg assay is a sandwich chemiluminescent microplate enzyme immunoassay and provides an alternative choice which is more cost-effective and potentially applicable in developing or resource-constrained countries and areas. A total of 411 serum samples were collected from patients during various phases of chronic hepatitis B (CHB) infection. The samples were assessed using the three assays, and the results were compared and analyzed. The results for the Architect, Elecsys, and WTultra assays were well correlated according to the overall results for the samples (correlation coefficients, rArchitect versus WTultra = 0.936, rArchitect versus Elecsys = 0.952, and rWTultra versus Elecsys = 0.981) and the various infection phases (rArchitect versus WTultra ranging from 0.67 to 0.975, rArchitect versus Elecsys ranging from 0.695 to 0.982, and rWTultra versus Elecsys ranging from 0.877 to 0.99). Additionally, consistent results were observed according to genotype (genotype B: rArchitect versus WTultra = 0.976, rArchitect versus Elecsys = 0.978, and rWTultra versus Elecsys = 0.979; genotype C: rArchitect versus WTultra = 0.950, rArchitect versus Elecsys = 0.963, and rWTultra versus Elecsys = 0.981) and hepatitis B virus (HBV) DNA levels (rArchitect = 0.540, rWTultra = 0.553, and rElecsys = 0.580). In conclusion, the Elecsys and WTultra assays were well correlated with the Architect assay, irrespective of the CHB infection phase or genotype. All of these assays are reliable for HBsAg quantification.
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Effects of bioactive cements incorporating zinc-bioglass nanoparticles on odontogenic and angiogenic potential of human dental pulp cells.
J Biomater Appl
PUBLISHED: 09-10-2014
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The objective of this study was to investigate the effects of bioactive calcium phosphate cements (CPC, ?-tricalcium phosphate-based) incorporating zinc-bioglass (ZnBG) on the odontogenic differentiation and angiogenesis of human dental pulp cells (HDPCs).
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Fibroblast Growth Factor Receptor 4 (FGFR4) Deficiency Improves Insulin Resistance and Glucose Metabolism under Diet-induced Obesity Conditions.
J. Biol. Chem.
PUBLISHED: 09-09-2014
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The role of fibroblast growth factor receptor 4 (FGFR4) in regulating bile acid synthesis has been well defined; however, its reported role on glucose and energy metabolism remains unresolved. Here, we show that FGFR4 deficiency in mice leads to improvement in glucose metabolism, insulin sensitivity, and reduction in body weight under high fat conditions. Mechanism of action studies in FGFR4-deficient mice suggest that the effects are mediated in part by increased plasma levels of adiponectin and the endocrine FGF factors FGF21 and FGF15, the latter of which increase in response to an elevated bile acid pool. Direct actions of increased bile acids on bile acid receptors, and other potential indirect mechanisms, may also contribute to the observed metabolic changes. The results described herein suggest that FGFR4 antagonists alone, or in combination with other agents, could serve as a novel treatment for diabetes.
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Increased mRNA levels of apolipoprotein M and apolipoprotein AI in the placental tissues with fetal macrosomia.
Arch. Gynecol. Obstet.
PUBLISHED: 09-07-2014
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The present study examined mRNA levels of apolipoprotein M (apoM) and apolipoprotein AI (apoAI) in the term placental tissues obtained from 37 women with normal birth weight neonates and from 37 women with macrosomic neonates (birth body weight ?4,000 g), and further discussed possible clinical significance of these observations.
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miRNA-646 suppresses osteosarcoma cell metastasis by downregulating fibroblast growth factor 2 (FGF2).
Tumour Biol.
PUBLISHED: 09-05-2014
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MicroRNAs are short regulatory RNAs that play crucial roles in cancer development and progression. MicroRNA-646 (miR-646) is downregulated in many human cancers, and increasing evidence indicates that it functions as a tumor suppressor. However, the role of miR-646 in osteosarcoma remains unclear. Expression levels of miR-646 in osteosarcoma cell lines and patient tissues were evaluated by quantitative real-time PCR (qRT-PCR), and the clinicopathological significance of the resultant data was later analyzed. Next, we investigated the role of miR-646 to determine its potential roles on osteosarcoma cell proliferation, migration, and invasion in vitro. A luciferase reporter assay was conducted to confirm the target gene of miR-646, and the results were validated in the osteosarcoma cell line. In this study, we found that miR-646 was downregulated in osteosarcoma cell lines and osteosarcoma tissues compared with normal osteoblast cell line NHOst and paired adjacent nontumor tissue. We found that a lower expression of miR-646 was associated with metastasis. In osteosarcoma cells, overexpression of miR-646 inhibited cell proliferation, migration, and invasion. In contrast, downregulation of miR-646 expression promoted osteosarcoma cell proliferation, migration, and invasion. Next, we identified that the FGF2 gene is a novel direct target of miR-646 in osteosarcoma cells. Moreover, enforced expression of FGF2 partially reversed the inhibition of cell proliferation, migration, and invasion that was caused by miR-646. Our study demonstrated that miR-646 might be a tumor suppressor in osteosarcoma via the regulation of FGF2, which provided a potential prognostic biomarker and therapeutic target.
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Engineering a sensitive visual-tracking reporter system for real-time monitoring phosphorus deficiency in tobacco.
Plant Biotechnol. J.
PUBLISHED: 09-05-2014
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Plant phosphorus (P) diagnosis is widely used for monitoring P status and guiding P fertilizer application in field conditions. The common methods for predicting plant response to P are time- and labour-consuming chemical measurements of the extractable soil P and plant P concentrations. In this study, we successfully generated a visual reporter system in tobacco (Nicotiana tabacum L.) to monitor plant P status by expressing of a Purple gene (Pr) isolated from cauliflower (Brassica oleracea var botrytis) driven by the promoter (Pro) of OsPT6, a P-starvation-induced rice gene. The leaves of OsPT6pro::Pr (PT6pro::Pr) transgenic tobacco continuously turned into dark purple with the increase of duration and severity of P deficiency, and recovered rapidly to basal green colour upon resupply of P. The expression of several anthocyanin biosynthesis involving genes was strongly activated in the transgenic tobacco in comparison to wild type under P-deficient condition. Such additive purple colour was not detected by deficiencies of other major- and micronutrients or stresses of salt, drought and cold. There was an extremely high correlation between P concentration and anthocyanin accumulation in the transgenic tobacco leaves. Using a hyperspectral sensing technology, P concentration in the leaves of transgenic plants could be predicted by the reflectance spectra at 554 nm wavelength with approximately 0.16 as the threshold value of the P deficiency. Taken together, the colour-based visual reporter system could be specifically and readily used for monitoring the plant P status by naked eyes and accurately assessed by spectral reflectance.
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Carotid baroreceptor stimulation: a potential solution for resistant hypertension.
Interv Neurol
PUBLISHED: 09-05-2014
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Resistant hypertension indicates that the blood pressure cannot reach the target value despite standard drug treatment, which harbors an increased risk for cardiovascular diseases. The role of the carotid sinus in regulating blood pressure has long been observed; thereby, the idea that treating resistant hypertension by stimulating carotid baroreceptors emerged. Nevertheless, this idea has been abandoned for years due to technical limitations. Recently, with the evolutions in implantable electrical devices, expectations for treating resistant hypertension with baroreceptor stimulation have increased. Positive results from several multicenter clinical trials further captured the researchers' enthusiasm for more effective baroreceptor-stimulating devices. This study reviews the recent progress in baroreceptor stimulation as a treatment alternative for resistant hypertension.
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Association study of miR?149 rs2292832 and miR?608 rs4919510 and the risk of hepatocellular carcinoma in a large?scale population.
Mol Med Rep
PUBLISHED: 09-04-2014
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Polymorphisms in pre?microRNAs (miRNAs) or mature miRNAs may influence miRNA processing or target binding, thus contributing to tumorigenesis and cancer development. The present study aimed to evaluate whether miR?149 rs2292832 (C>T) and miR?608 rs4919510 (G>C) are associated with the risk and clinical characteristics of hepatocellular carcinoma (HCC) in a large?scale population. miR?149 rs2292832 and miR?608 rs4919510 were genotyped in a total of 993 patients with HCC and 992 unrelated healthy subjects by Sequenom MassARRAY. The results showed that, compared with the reference CC genotype, the TC+TT genotype of miR?149 was more highly associated with HCC [CC vs. TC+TT: Odds ratio (OR)=1.384, 95% confidence interval (CI)=1.013?1.892, P=0.041], and was also associated with an increased risk of hepatitis B virus (HBV)?associated HCC (CC vs. TC+TT: OR=1.453, 95% CI=1.034?2.042, P=0.031). However, no significant association between miRNA?608 rs4919510 and the risk of HCC/HBV?associated HCC was found. In addition, these two SNPs were shown not to be correlated with a range of clinical characteristics. The present study may provide an indicator for identification of the high risk of HCC in patients.
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A mesoporous "shell-in-shell" structured nanocatalyst with large surface area, enhanced synergy, and improved catalytic performance for Suzuki-Miyaura coupling reaction.
Chem. Commun. (Camb.)
PUBLISHED: 09-04-2014
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A novel mesoporous "shell-in-shell" structured nanocatalyst (@Pd/meso-TiO2/Pd@meso-SiO2) with large surface area, enhanced synergy, and improved catalytic performance is created for catalyzing Suzuki-Miyaura coupling and 4-nitrophenol reduction reactions.
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A composite cathode based on scandium doped titanate with enhanced electrocatalytic activity towards direct carbon dioxide electrolysis.
Phys Chem Chem Phys
PUBLISHED: 09-03-2014
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A composite cathode based on redox-stable La0.2Sr0.8TiO(3+?) (LSTO) can perform direct carbon dioxide electrolysis; however, the insufficient electro-catalytic activity limits the electrode performances and current efficiencies. In this work, catalytically active scandium is doped into LSTO to enhance the electro-catalytic activity for CO2 electrolysis. The structures, electronic conductivities and ionic conductivities of La0.2Sr0.8Ti(1-x)Sc(x)O (LSTS(x)O) (x = 0, 0.05, 0.1, 0.15 and 0.2) are systematically studied and further correlated with electrode performances. The ionic conductivities of single-phase LSTS(x)O (x = 0, 0.05, 0.1 and 0.15) remarkably improve versus the scandium doping contents though the electrical conductivities gradually change in an adverse trend. Electrochemical measurements demonstrate promising electrode polarisation of LSTS(x)O electrodes and increasing scandium doping contents accordingly improve electrode performances. The Faradic efficiencies of carbon dioxide electrolysis are enhanced by 20% with LSTS0.15O in contrast to bare LSTO electrodes in a solid oxide electrolyser at 800 °C.
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Probing the spatial and momentum distribution of confined surface states in a metal coordination network.
Chem. Commun. (Camb.)
PUBLISHED: 09-03-2014
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The Shockley surface state on Cu(111) reacts sensitively to the perturbation by molecular adsorbates on the surface. In the porous structure of a metal-coordinated molecular network on Cu(111), the surface state is confined to a series of discrete states. Energy and momentum of eigenstates in the pores are related to both the energy dispersion of the free surface state and the geometric and energetic details of the confining barrier formed by the molecular network. The penetration of the confined state into the barrier is found to be sensitive to the constituting architectural elements.
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[Successful management of massive gastrointestinal bleeding using recombinant factor VIIa in an elderly patient with respiratory and renal failure].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 09-02-2014
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Recombinant activated factor VII (rFVIIa) is a novel therapeutic agent for life-threatening massive gastrointestinal bleeding. We report a case of massive gastrointestinal bleeding in a 78-year-old female patient with respiratory and renal failure. After failure of management of the bleeding with routine pharmacotherapy, we gave the patient rFVIIa injection at the dose of 20 µg/kg and the bleeding was rapidly controlled. Adverse side effects of the drug were not observed in this patient.
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Architecture engineering toward highly active palladium integrated titanium dioxide yolk-double-shell nanoreactor for catalytic applications.
Nanoscale
PUBLISHED: 09-01-2014
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Rational design of the hierarchical architecture of a material with well controlled functionality is crucially important for improving its properties. In this paper, we present the general strategies for rationally designing and constructing three types of hierarchical Pd integrated TiO2 double-shell architectures, i.e. yolk-double-shell TiO2 architecture (Pd@TiO2/Pd@TiO2) with yolk-type Pd nanoparticles residing inside the central cavity of the hollow TiO2 structure; ultrafine Pd nanoparticles homogenously dispersed on both the external and internal surfaces of the inner TiO2 shell; and double-shell TiO2 architecture (@TiO2/Pd@TiO2) with Pd nanoparticles solely loaded on the external surface of the inner TiO2 shell, and double-shell TiO2 architecture (@TiO2@Pd@TiO2) with Pd nanoparticles dispersed in the interlayer space of double TiO2 shells, via newly developed Pd(2+) ion-diffusion and Pd sol impregnation methodologies. These architectures are well controlled in structure, size, morphology, and configuration with Pd nanoparticles existing in various locations. Owing to the variable synergistic effects arising from the location discrepancies of Pd nanoparticle in the architectures, they exhibit remarkable variations in catalytic activity. In particular, different from previously reported yolk-shell structures, the obtained yolk-double-shell Pd@TiO2/Pd@TiO2 architecture, which is revealed for the first time, possesses a uniform hierarchical structure, narrow size distribution, and good monodispersibility, and it creates two Pd-TiO2 interfaces on the external and internal surfaces of the inner TiO2 shell, leading to the strongest synergistic effect of Pd nanoparticles with TiO2 shell. Furthermore, the interlayer chamber between the double TiO2 shells connecting with the central cavity of the hollow TiO2 structure through the mesoporous TiO2 wall forms a nanoreactor for enriching the reactants and preventing the deletion of Pd nanoparticles during the reaction, thus greatly accelerating the reaction speed. Owing to its structural features, yolk-double-shell Pd@TiO2/Pd@TiO2 architecture exhibits extremely high catalytic performance on the Suzuki-Miyaura coupling reaction. The synthetic methodologies are robust for fabricating double-shell architectures with various configurations for applications such as in catalysis, drug delivery, and medicine release. The obtained double-shell architectures may be used as novel catalyst systems with highly efficient catalytic performance for other catalytic reactions.
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[Severe idiopathic pulmonary arterial hypertension in pregnancy: a review of 10 cases].
Zhonghua Fu Chan Ke Za Zhi
PUBLISHED: 08-30-2014
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To study the impact of severe idiopathic pulmonary arterial hypertension (IPAH) on pregnancy outcome and to investigate the effect of multidisciplinary approach during pregnancy on the pregnancy outcome in pregnant woman with severe IPAH.
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[Analysis of epidemiological characteristics of acute pesticide poisoning during 2007-2013 in Jinan, China].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 08-30-2014
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To investigate the epidemiological characteristics of acute pesticide poisoning in Jinan, China and to provide effective proposals for the prevention and control of pesticide poisoning.
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[Zero-profile implant for anterior cervical discectomy and fusion in treating single cervical disc herniation].
Zhongguo Gu Shang
PUBLISHED: 08-30-2014
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To explore the efficacy and safety of zero-profile implant for anterior cervical discectomy and fusion (ACDF) in treating single cervical disc herniation.
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Relationships of COX2 and MMP12 genetic polymorphisms with chronic obstructive pulmonary disease risk: a meta-analysis.
Mol. Biol. Rep.
PUBLISHED: 08-28-2014
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We performed the present meta-analysis in an attempt to confirm the correlation of genetic polymorphisms in the COX2 and MMP12 genes with the susceptibility to chronic obstructive pulmonary disease (COPD). We searched English database such as PubMed, CISCOM, CINAHL, Web of Science, Google Scholar and several Chinese database for meta-analysis. There were no specific language restrictions. Two investigators systematically extracted relevant data within those included studies. Crude ORs with its corresponding 95 % CI were calculated. STATA 12.0 software was adopted for statistical analysis. The impact of COX2 and MMP12 genetic polymorphisms on the pathogenesis of COPD was investigated in the current study with a total of 10 case-control studies, which includes 1,751 COPD patients and 2,472 healthy subjects. Four common polymorphisms, including rs689466 G > A and rs20417 G > C in the COX2 gene, rs652438 A > G and rs2276109 A > G were evaluated in the MMP12 gene. Pooled OR of the present studies and results showed that the frequency of COX2 rs20417 polymorphism was prevalent in COPD patients than those of healthy subjects (C allele vs. G allele OR = 1.33, 95 % CI 1.06-1.67, P = 0.014; GC + CC vs. GG OR = 1.86, 95 % CI 1.07-3.24, P = 0.029; respectively). However, we found no significant correlation between COX2 rs689466 polymorphism and the risk of COPD (all P > 0.05). Furthermore, our meta-analysis illustrated that individuals with MMP12 rs652438 polymorphism had significantly increased risk of developing COPD (G allele vs. A allele OR = 1.62, 95 % CI 1.08-2.42, P = 0.020; AG + GG vs. AA OR = 2.14, 95 % CI 1.12-4.09, P = 0.021; respectively). Nevertheless, no positive relation was detected between MMP12 rs2276109 variant and the risk of COPD. Our meta-analysis indicates that COX2 and MMP12 genetic polymorphisms may be strongly implicated in the development of COPD, especially for the COX2 rs20417 and MMP12 rs652438 polymorphisms. Thus, COX2 and MMP12 genetic polymorphisms could potentially be utilized as helpful biomarkers for early diagnosis of COPD.
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Preparation of Cross-Linked Enzyme Aggregates of Trehalose Synthase via Co-aggregation with Polyethyleneimine.
Appl. Biochem. Biotechnol.
PUBLISHED: 08-28-2014
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Trehalose synthase (TreS) from Meiothermus ruber was co-aggregated with polyethyleneimine (PEI) and precipitated with polyethylene glycol (PEG), followed by cross-linking with glutaraldehyde to obtain TreS-polyethyleneimine cross-linked enzyme aggregates (termed as CLEAs-PEI-PEG). The TreS solution at 0.5 mg mL(-1) protein concentration, with PEI at a mass ratio of 1:0.8 (enzyme/PEI, w/w) and 25 % (w/v) PEG concentration were found to be most adequate for the co-aggregation of TreS. CLEAs-PEI-PEG was most active with glutaraldehyde at a mass ratio of 1:0.5 (enzyme/glutaraldehyde, w/w) to cross-link the co-aggregates. The CLEAs-PEI-PEG prepared in this work had an optimum pH of 6.5 and optimum temperature of 60 °C. For lower concentrations of enzyme, using PEI could enhance the cross-linking efficiency of TreS. The thermal stability and pH tolerance of CLEAs-PEI-PEG were significantly improved. Scanning electron microscopy revealed that the main structure of CLEAs-PEI-PEG showed scaffolding morphology which was constituted by structured ball-like particles with a size of 1-2.5 ?m in diameter.
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Raman spectroscopy for in-line and off-line quantification of poorly soluble drugs in strip films.
Int J Pharm
PUBLISHED: 08-27-2014
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Raman spectroscopy was used as a process analytical technology (PAT) tool for in-line measurement of active pharmaceutical ingredient (API) content during continuous manufacturing of strip films containing nanoparticles of poorly water-soluble APIs. Fenofibrate and naproxen were used as model APIs, whose concentrations ranged from 3% to 26% (w/w) in the model calibration. For both in-line and off-line measurements, calibration models employed partial least square (PLS) analysis, yielding correlation coefficients (R(2)) greater than 0.9946 and root mean squared error of calibration (RMSEC) of about 0.44%, indicating the validity and accuracy of the calibration. The robustness of Raman spectroscopy as a PAT tool was established by considering three processing parameters after substrate interference correction: sensing location, substrate speed and film thickness. Calibration models for each API were validated using a separate batch of strip films by predicting the API concentrations to within ±1.3%. Principal component analysis (PCA) was used to explain the interactions between processing variables and calibration models, which suggest that besides API concentration, film thickness could also be monitored using Raman spectroscopy. The results demonstrate the potential of Raman spectroscopy as an effective PAT tool for novel strip film manufacturing process, facilitating detection of drug form and concentration in real-time.
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Development of an enzyme-linked immunospot assay for determination of rotavirus infectivity.
J. Virol. Methods
PUBLISHED: 08-27-2014
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Conventional rotavirus infectivity assays are time consuming, labor intensive, and with low sample throughput. To overcome these problems, a 96-well microplate enzyme-linked immunospot assay (Elispot) was developed for the measurement of rotavirus infectious titers. The infected MA104 cells were stained with a horseradish peroxidase-conjugated anti-VP6 monoclonal antibody followed by detection with an ELISPOT analyzer. A linear relationship was found between spot number and input of rotavirus dose in SA11 and 10 rotavirus isolates of different genotypes. The propagation of rotavirus SA11 in MA104 cells was monitored, and the neutralizing activity of serum samples and monoclonal antibodies was determined. The 50% neutralizing titer (NT50) of serum and 50% inhibitory concentration (IC50) of monoclonal antibodies were correlated well with the results determined by ELISA-based neutralization assay. In conclusion, a rapid and semi-automated procedure to determine rotavirus infectivity was developed, which will be useful to study the infectivity and the neutralizing epitopes of rotavirus.
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Dispersion interaction stabilizes sterically hindered double fullerenes.
Chemistry
PUBLISHED: 08-27-2014
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By state-of-the-art quantum chemical methods, we show that for bulky functional groups like cyclohexane, [20]fullerene, dodecahedrane, and C60 , the attractive dispersion interaction can have a greater impact on stereochemistry than the repulsive steric effect, making the compact isomer the more stable one. In particular, for the double C60 adduct of pentacene 1, the syn isomer should be the main product instead of the anti one inferred in the original synthesis experiment (Y. Murata et?al., J. Org. Chem.- 1999, 64, 3483). With and without dispersion interactions taken into account, the Gibbs energy difference ?G(syn-anti) is -6.36 and +1.15?kcal?mol(-1) , respectively. This study reminds us that dispersion interactions as well as electrostatic or hyperconjugation effects, etc. can lead to some unusual stereochemical phenomena.
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Prognostic value of epidermal growth factor receptor mutations in resected non-small cell lung cancer: a systematic review with meta-analysis.
PLoS ONE
PUBLISHED: 08-27-2014
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The prognostic value of epidermal growth factor receptor (EGFR) mutations in resected non-small cell lung cancer (NSCLC) remains controversial. We performed a systematic review with meta-analysis to assess its role.
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An aptamer targets HBV core protein and suppresses HBV replication in HepG2.2.15 cells.
Int. J. Mol. Med.
PUBLISHED: 08-19-2014
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Hepatitis B virus (HBV)-related hepatitis is a major health concern worldwide. As current anti-HBV therapies are limited, it is essential to develop new strategies. Aptamer, a newly developed adaptive molecule (single-strand DNA or RNA also known as nucleotide antibody), is a new strategy for clinical diagnosis and therapy due to its high affinity and specificity. In the present study, by systematic evolution of ligand by exponential enrichment (SELEX), aptamers were screened against the core protein of HBV (HBc) from a random ssDNA library. Quantitative PCR (qPCR) results showed that the binding proportions of the SELEX-enriched aptamer pools were increased with the SELEX rounds, until round seven. Thus, the pool of round seven was cloned. Following the sequence analysis of a total of 90 clones by Macaw software, five aptamer candidates were selected and their affinity to HBc was tested by dot blot. Apt.No.28, which had sequence replicates in the clones, was shown to have a high affinity. Furthermore, by agarose gel electrophoresis-capillary transfer-blotting and qPCR, Apt.No.28 was shown to inhibit the assembly of the nucleocapsid, reducing extracellular HBV DNA whose synthesis relied on the formation of the nucleocapsid, indicating its role in suppressing HBV replication. The results provided a new ideal targeting molecule and may facilitate the strategy for targeted therapy as well as drug development of HBV-related diseases.
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Quantum Hamiltonian identification from measurement time traces.
Phys. Rev. Lett.
PUBLISHED: 08-18-2014
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Precise identification of parameters governing quantum processes is a critical task for quantum information and communication technologies. In this Letter, we consider a setting where system evolution is determined by a parametrized Hamiltonian, and the task is to estimate these parameters from temporal records of a restricted set of system observables (time traces). Based on the notion of system realization from linear systems theory, we develop a constructive algorithm that provides estimates of the unknown parameters directly from these time traces. We illustrate the algorithm and its robustness to measurement noise by applying it to a one-dimensional spin chain model with variable couplings.
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Increased performance of a tubular microbial fuel cell with a rotating carbon-brush anode.
Biosens Bioelectron
PUBLISHED: 08-17-2014
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A novel method was proposed to improve the power output of microbial fuel cells (MFCs) by rotating the carbon-brush anode. The MFC with a rotating anode produced a peak power density of 210±3 W/m(3) and a maximum current density of 945±43 A/m(3), 1.4 and 2.7 times higher than those of the non-rotating case, respectively. The difference of the electrochemical impedance spectroscopy and cyclic voltammetry before and after anode rotation clearly suggested that the mass transfer to the spiral space was enhanced by the rotating anode. Furthermore, Tafel plots analysis also revealed that the rotating anode can improve the electrochemical activity of the biofilm.
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Synthesis of a cu2+-selective probe derived from rhodamine and its application in cell imaging.
Sensors (Basel)
PUBLISHED: 08-15-2014
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A new fluorescent probe P based on rhodamine for Cu2+ was synthesized and characterized. The new probe P showed high selectivity to Cu2+ over other tested metal ions. With optimal conditions, the proposed probe P worked in a wide linear range of 1.0 × 10-6-1.0 × 10-5 M with a detection limit of 3.3 × 10-7 M Cu2+ in ethanol-water solution (9:1, v:v, 20 mM HEPES, pH 7.0). Furthermore, it has been used for imaging of Cu2+ in living cells with satisfying results.
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A hybrid dielectrophoretic and hydrophoretic microchip for particle sorting using integrated pre-focusing and sorting steps.
Electrophoresis
PUBLISHED: 08-13-2014
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This work explores dielectrophoresis (DEP)-active hydrophoresis in sorting particles and cells. The device consists of pre-focusing region and sorting region with great potential to be integrated into advanced lab-on-a-chip bioanalysis devices. Particles or cells can be focused in the pre-focusing region and then sorted in the sorting region. The DEP-active hydrophoretic sorting is not only based on size but also on dielectric properties of the particles or cells of interest without any labelling. A mixture of 3 ?m and 10 ?m particles were sorted and collected from corresponding outlets with high separation efficiency. According to the different dielectric property of viable and nonviable Chinese Hamster Ovary (CHO) cells at the medium conductivity of 0.03 S/m, the viable CHO cells were focused well and sorted from cell sample with a high purity. This article is protected by copyright. All rights reserved.
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Association between a variant in microRNA-646 and the susceptibility to hepatocellular carcinoma in a large-scale population.
ScientificWorldJournal
PUBLISHED: 08-07-2014
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Single-nucleotide polymorphisms in microRNAs play important roles in oncogenesis and cancer development. Objective. We aim to explore whether miR-646 rs6513497 is associated with the risk of hepatocellular carcinoma.
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Diallyl disulfide induces G2/M arrest and promotes apoptosis through the p53/p21 and MEK-ERK pathways in human esophageal squamous cell carcinoma.
Oncol. Rep.
PUBLISHED: 07-25-2014
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Esophageal squamous cell carcinoma (ESCC) is an aggressive tumor with high incidence and mortality worldwide. Diallyl disulfide (DADS) is a natural organosulfur compound, isolated from garlic. In this study, MTT assay showed that DADS significantly reduced cell viability in a dose- and time-dependent manner in ESCC cells, with lower toxicity in normal liver cells. Cell cycle analysis revealed that DADS made G2/M phase arrest. Molecular analysis suggested that this cell cycle arrest was likely made by the decrease of cyclin B1, cdc2, p-cdc2, cdc25c in concomitance with activation of the p53/p21 pathway. Apoptosis was detected by Annexin V/PI staining. The molecule markers showed that DADS induced apoptosis through activating caspases, altering the Bax/Bcl-2 balance and suppressing the MEK-ERK pathway. Our data indicated that DADS has the potential to be an effective and safe anticancer agent for ESCC therapy in the near future.
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MiR99a modulates MMP7 and MMP13 to regulate invasiveness of Kaposi's sarcoma.
Tumour Biol.
PUBLISHED: 07-19-2014
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Matrix metalloproteinases (MMPs) and microRNAs (miRNAs) are associated with Kaposi's sarcoma (KS) tumorigenesis. To date, the molecular basis underlying crosstalk of MMPs and miRNAs in KS remains unexplored. From the resected KS samples, we detected significant correlation of miRNA99a (miR99a), with MMP7 and MMP13, but not with MMP9. To define whether a causal link exists, we used a human KS line, SLK, to study the molecular basis of miR99a and activation of MMP7, MMP9, and MMP13. We found that overexpression of miR99a in SLK cells decreased MMP7 and MMP13, but not MMP9. Similarly, MiR99a inhibition in SLK cells activated MMP7 and MMP13, but did not affect expression of MMP9. These data suggest that MMP7 and MMP13 seem to be regulated by miR99a, while MMP9 seems to be regulated in a miR99a-independent manner. Inhibition of PI3k/Akt signaling pathway significantly abolished the effect of miR99a-knockdown on MMP7, but not MMP13 activation, while inhibition of ERK/MAPK signaling pathway significantly abolished the effect of miR99a-knockdown on MMP13, but not MMP7 activation. Taken together, our data suggest that miR99a inhibits MMP7 and MMP13 through PI3k/Akt and ERK/MAPK signaling pathway, respectively, in KS. Thus, miR99a, MMP7, and MMP13 appear to be promising therapeutic targets for preventing the metastasis of KS.
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Silica vesicles as nanocarriers and adjuvants for generating both antibody and T-cell mediated immune resposes to Bovine Viral Diarrhoea Virus E2 protein.
Biomaterials
PUBLISHED: 07-17-2014
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Bovine Viral Diarrhoea Virus (BVDV) is widely distributed in cattle industries and causes significant economic losses worldwide annually. A limiting factor in the development of subunit vaccines for BVDV is the need to elicit both antibody and T-cell-mediated immunity as well as addressing the toxicity of adjuvants. In this study, we have prepared novel silica vesicles (SV) as the new generation antigen carriers and adjuvants. With small particle size of 50 nm, thin wall (~6 nm), large cavity (~40 nm) and large entrance size (5.9 nm for SV-100 and 16 nm for SV-140), the SV showed high loading capacity (? 250 ?g/mg) and controlled release of codon-optimised E2 (oE2) protein, a major immunogenic determinant of BVDV. The in vivo functionality of the system was validated in mice immunisation trials comparing oE2 plus Quil A (50 ?g of oE2 plus 10 ?g of Quil A, a conventional adjuvant) to the oE2/SV-140 (50 ?g of oE2 adsorbed to 250 ?g of SV-140) or oE2/SV-140 together with 10 ?g of Quil A. Compared to the oE2 plus Quil A, which generated BVDV specific antibody responses at a titre of 10(4), the oE2/SV-140 group induced a 10 times higher antibody response. In addition, the cell-mediated response, which is essential to recognise and eliminate the invading pathogens, was also found to be higher [1954-2628 spot forming units (SFU)/million cells] in mice immunised with oE2/SV-140 in comparison to oE2 plus Quil A (512-1369 SFU/million cells). Our study has demonstrated that SV can be used as the next-generation nanocarriers and adjuvants for enhanced veterinary vaccine delivery.
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Uncovering a Glycosyltransferase Provides Insights into the Glycosylation Step during Macrolactin and Bacillaene Biosynthesis.
Chembiochem
PUBLISHED: 07-16-2014
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Macrolactins (MLNs) have unique structural patterns containing a 24-membered ring lactone and diverse bioactivities. The MLN skeleton is biosynthesized via a trans-acyl transferase (AT) type I polyketide synthase (PKS) pathway, but the tailoring steps are still unknown. Herein, we report the identification of a glycosyltransferase (GT) gene bmmGT1, which is located at different locus from the MLN gene cluster in the genome of marine-derived Bacillus marinus B-9987, and its functional characterization as an MLN GT, thus affording five novel MLNs analogues. Surprisingly, this GT is also capable of catalyzing the glycosylation of bacillaenes (BAEs), which are the prototypes of trans-AT polyketides, thus suggesting broad substrate flexibility. These results provide the first significant insights into the glycosylation step in MLN and BAE biosynthetic pathways.
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In situ formation of oxygen vacancy in perovskite Sr0.95Ti0.8Nb0.1M0.1O3 (M = Mn, Cr) toward efficient carbon dioxide electrolysis.
Sci Rep
PUBLISHED: 07-11-2014
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In this work, redox-active Mn or Cr is introduced to the B site of redox stable perovskite Sr0.95Ti0.9Nb0.1O3.00 to create oxygen vacancies in situ after reduction for high-temperature CO2 electrolysis. Combined analysis using X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric analysis confirms the change of the chemical formula from oxidized Sr0.95Ti0.9Nb0.1O3.00 to reduced Sr0.95Ti0.9Nb0.1O2.90 for the bare sample. By contrast, a significant concentration of oxygen vacancy is additionally formed in situ for Mn- or Cr-doped samples by reducing the oxidized Sr0.95Ti0.8Nb0.1M0.1O3.00 (M = Mn, Cr) to Sr0.95Ti0.8Nb0.1M0.1O2.85. The ionic conductivities of the Mn- and Cr-doped titanate improve by approximately 2 times higher than bare titanate in an oxidizing atmosphere and 3-6 times higher in a reducing atmosphere at intermediate temperatures. A remarkable chemical accommodation of CO2 molecules is achieved on the surface of the reduced and doped titanate, and the chemical desorption temperature reaches a common carbonate decomposition temperature. The electrical properties of the cathode materials are investigated and correlated with the electrochemical performance of the composite electrodes. Direct CO2 electrolysis at composite cathodes is investigated in solid-oxide electrolyzers. The electrode polarizations and current efficiencies are observed to be significantly improved with the Mn- or Cr-doped titanate cathodes.
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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.