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Find video protocols related to scientific articles indexed in Pubmed.
Simultaneous realization of two approaches to white light in single-component phosphors.
Opt Express
PUBLISHED: 11-18-2014
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A novel single-component warm white light-emitting Sr2Ca0.995MoO6: Sm3+ 0.005 phosphor was synthesized by solid-state reaction. The photoluminescence excitation spectra ranging from 300 to 450 nm and 460 to 500 nm broadly are observed. Direct full-color warm white light [(x, y) = 0.3221, 0.3525] was realized in this single-phase phosphor with exposure to 380 nm UV light. When this phosphor is pumped by 466 nm radiation we obtained yellow emission with an intense red component, suggesting that this material is also competitive as a blue-pumped yellow phosphor. Thus two approaches to white light are realized simultaneously in Sm3+ doped single-component phosphor for the first time. The quantum yield and the reliability of the as-synthesized phosphors for White LED applications were also investigated.
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[Effect of PD-1 deficiency on atherogenic immune responses].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 11-18-2014
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To explore the functional changes of T lymphocyte from PD-1(-/-) mice and the effects on atherogenic immune responses.
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AgNP-DNA@GQDs Hybrid: A New Approach for Sensitive Detection of H2O2 and Glucose via Simultaneous AgNP Etching and DNA Cleavage.
Anal. Chem.
PUBLISHED: 11-13-2014
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A growing body of evidence suggests that hydrogen peroxide (H2O2) plays an active role in the regulation of various physiological processes. Development of sensitive probes for H2O2 is an urgent work. In this study, we proposed a DNA-mediated silver nanoparticles and graphene quantum dots hybrid nanocomposite (AgNP-DNA@GQDs) for sensitive fluorescent detection of H2O2 and the sensing mechanism is based on the etching effect of H2O2 to AgNP and the cleavage of as-generated hydroxyl radicals (•OH) to DNA. The formation of AgNP-DNA@GQDs nanocomposite results in fluorescence quenching of GQDs by AgNP through the resonance energy transfer. Upon H2O2 addition, the energy transfer between AgNP and GQDs mediated by DNA was weakened and obvious fluorescence recovery of GQDs could be observed. It is worth noting that the reaction product •OH between H2O2 and AgNP could cleave the DNA-bridge and thus enhance the AgNP-DNA@GQDs disassembly to further achieve signal amplification. With optimal condition, the approach achieves lowest limit of detection values of 0.11 ?M. Moreover, this nanocomposite is further extended to the detection of glucose in human urine combining with glucose oxidase (GOx) for the oxidation of glucose and formation of H2O2. The glucose concentrations in human urine are detected with satisfactory recoveries of 94.6-98.8% which holds potential of ultrasensitive quantitative analysis of glucose and supply valuable information for diabetes mellitus research and clinical diagnosis.
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"Green" Synthesis of Unnatural Poly(Amino Acid)s with Zwitterionic Character and pH-Responsive Solution Behavior, Mediated by Linear-Dendritic Laccase Complexes.
Biomacromolecules
PUBLISHED: 10-28-2014
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This article describes the enzyme-catalyzed "green" synthesis of an unnatural poly(amino acid). dl-Tyrosine was polymerized under environmentally friendly conditions using linear-dendritic laccase complexes as initiators and water as solvent. The influence of the dendron generation in the linear-dendritic copolymers, the monomer concentration, and time and temperature on the polymer yields and molecular masses was investigated. Depending on the reaction conditions poly(tyrosine) with molecular mass (Mw) up to 82 kDa could be obtained in yields ranging between 45 and 69%. It was found that the linear-dendritic laccase complexes can induce further chain growth upon addition of fresh monomer to the preformed poly(tyrosine) in a fashion resembling the classic "living" polymerization. The structure of the poly(tyrosine) was investigated by NMR, FT-IR, and MALDI-TOF and it was discovered that the polymer chains consist of phenol repeating units linked together by C-C and C-O bonds randomly distributed along the backbone of the polymers. The materials formed are completely water-soluble and behave as typical poly(zwitterions) changing charge and size with the medium pH. DLS measurements reveal that the zeta potential of the polymers can vary between +15 mV at pH 1.2 with hydrodynamic diameter (Dh) = 6.7 nm to -35 mV at pH 11.8 and Dh = 10 nm. The isoelectric point was found at pH = 2.3-2.6, where Dh of the polymer is at the minimum (2.4 nm).
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A FeCl2-graphite sandwich composite with Cl doping in graphite layers: a new anode material for high-performance Li-ion batteries.
Nanoscale
PUBLISHED: 10-23-2014
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A composite with FeCl2 nanocrystals sandwiched between Cl-doped graphite layers has been created via a space-confined nanoreactor strategy. This composite can be used as a new type of anode material for Li-ion batteries, which exhibit high reversible capacity and superior rate capability with excellent cycle life.
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Prophylactic cranial irradiation for patients with small-cell lung cancer: a systematic review of the literature with meta-analysis.
BMC Cancer
PUBLISHED: 10-17-2014
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Small cell lung cancer (SCLC) accounts for about 13% of all lung cancer cases. Small cell lung cancer (SCLC) accounts for about 13% of all lung cancer cases. The purpose of the present article is to assess the role of prophylactic cranial irradiation (PCI) in small cell lung cancer (SCLC) by performing a systematic review of the randomized trials published in the literature.
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NLRP3 and downstream cytokine expression elevated in the monocytes of patients with coronary artery disease.
Arch Med Sci
PUBLISHED: 10-03-2014
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Pattern recognition receptor (PRR)-mediated signaling pathways have recently been elucidated to bridge the innate immune system and atherosclerosis. NLRP3 is among the family members of NOD-like receptors (NLRs), a type of PRRs. At present, most studies about the NLRP3 inflammasome focus on animal models and immune cells. Limited information is available regarding the role of NLRP3 in patients with coronary artery disease (CAD).
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Synthesis of iron oxide coated fluoridated HAp/Ln(3+) (Ln = Eu or Tb) nanocomposites for biological applications.
Chem. Commun. (Camb.)
PUBLISHED: 10-01-2014
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Fluorescent-magnetic iron oxide coated fluoridated HAp/Ln(3+) (Ln = Eu or Tb) nanocomposites were prepared. After transforming hydrophobic fluoridated HAp/Ln(3+) nanorods into hydrophilic ones, iron oxide particles were coated on their surface via thermal decomposition of Fe(acac)3. Fluorescent-magnetic nanocomposites developed in this study demonstrate excellent fluorescent-magnetic properties and prominent biocompatibility.
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PINBPA: Cytoscape app for network analysis of GWAS data.
Bioinformatics
PUBLISHED: 09-25-2014
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Protein interaction network-based pathway analysis (PINBPA) for genome-wide association studies (GWAS) has been developed as a Cytoscape app, to enable analysis of GWAS data in a network fashion. Users can easily import GWAS summary-level data, draw Manhattan plots, define blocks, prioritize genes with random walk with restart, detect enriched subnetworks and test the significance of subnetworks via a user-friendly interface.
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GPU-based skin texture synthesis for digital human model.
Biomed Mater Eng
PUBLISHED: 09-18-2014
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Skin synthesis is important for the actual appearance of digital human models. However, it is difficult to design a general algorithm to efficiently produce high quality results. This paper proposes a parallel texture synthesis method for large scale skin of digital human models. Two major procedures are included in this method, a parallel matching procedure and a multi-pass optimizing procedure. Compared with other methods, this algorithm is easy to use, requires only a small size of skin image as input, and generates an arbitrary size of skin texture with high quality. As demonstrated by experiments, the effectiveness of this skin texture synthesis method is confirmed.
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ent-Kaurane-based regio- and stereoselective inverse electron demand hetero-Diels-Alder reactions: synthesis of dihydropyran-fused diterpenoids.
Org. Biomol. Chem.
PUBLISHED: 09-17-2014
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A mild and concise approach for the construction of a 3,4-dihydro-2H-pyran ring integrated into the A-ring of the natural product oridonin using an optimized inverse electron demand hetero-Diels-Alder (IED HDA) reaction is reported herein. A self-dimerization of the exocyclic enone installed in the A-ring through a homo-HDA reaction was identified to exclusively give a dimeric ent-kaurane diterpenoid with the spirochroman core. Moreover, efficient cross-HDA cycloadditions of this enone with various vinyl ethers or vinyl sulfides, instead of its own homo-HDA dimerization, were achieved in a regio- and stereoselective manner, thus providing access to novel dihydropyran-fused diterpenoids as potential anticancer agents to overcome chemoresistance.
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Secreted frizzled?related protein 2 is epigenetically silenced and functions as a tumor suppressor in oral squamous cell carcinoma.
Mol Med Rep
PUBLISHED: 09-05-2014
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The role of epigenetic inactivation of secreted frizzled?related protein 2 (SFRP2) and its functions in the development of oral squamous cell carcinoma (OSCC) remain to be elucidated. The present study demonstrated that SFRP2 mRNA was detected in 97.96% of tumor?adjacent normal tissues, while its expression was only detected in 16.33% of the tumor samples. In addition, the loss of SFRP2 expression was associated with hypermethylation of its promoter. As expected, the overexpression of SFRP2 in OSCC cell lines (Tca8113) suppressed cell proliferation and arrested the cell cycle in the G1 phase. Overexpression of SFRP2 also effectively repressed tumor growth in xenograft animals. Mechanistic investigations revealed that SFRP2 inhibited the development of OSCC in vitro and in vivo through an increase in the expression levels of glycogen synthase kinase?3? and a decrease in the expression level of cyclin D1, a direct read?out gene of active Wnt signaling. In addition, an increase in the expression of ??catenin was observed in the Tca8113/SFRP2 cells and in the animal models overexpressing SFRP2. Therefore, the results of the present study provide insight into the role of SFRP2 as a functional tumor suppressor in the development of OSCC through inhibition of the Wnt signaling pathway. Further studies on the precise mechanisms underlying the inhibition of Wnt signaling by SFRP2 and its association with ??catenin are required.
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Phenotypic and functional characterization of cytokine-induced killer cells derived from preterm and term infant cord blood.
Oncol. Rep.
PUBLISHED: 09-01-2014
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Cord blood has gradually become an important source for hematopoietic stem cell transplantation (HSCT) in the human, particularly in pediatric patients. Adoptive cellular immunotherapy of patients with hematologic malignancies after umbilical cord blood transplant is crucial. Cytokine?induced killer (CIK) cells derived from cord blood are a new type of antitumor immune effector cells in tumor prevention and treatment and have increasingly attracted the attention of researchers. On the other hand, it has been suggested that preterm infant cord blood retains an early differentiation phenotype suitable for immunotherapy. Therefore, we determined the phenotypic and functional characterization of CIK cells derived from preterm infant cord blood (PCB-CIK) compared with CIK cells from term infant cord blood (TCB-CIK). Twenty cord blood samples were collected and classified into two groups based on gestational age. Cord blood mononuclear cells (CBMCs) were isolated, cultured and induced to CIK cells in vitro. We used flow cytometry to detect cell surface markers, FlowJo software to analyze the proliferation profile and intracellular staining to test the secretion of cytokines. Finally, we evaluated the antitumor activity of CIK cells against K562 in vitro. Compared with TCB-CIK, PCB-CIK cells demonstrated faster proliferation and higher expression of activated cell surface markers. The secretion of IL-10 was lower in PCB-CIK cells while the expression of perforin and CD107a had no significant difference between the two cell groups. PCB-CIK cells exhibited a high proliferation rate while the cytotoxic activity had no difference between the PCB-CIK and TCB-CIK cells. Hence preterm infant cord blood may be a potential source for immunotherapy.
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Complete genomic sequence of the Vibrio alginolyticus lytic bacteriophage PVA1.
Arch. Virol.
PUBLISHED: 08-27-2014
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A novel Vibrio alginolyticus lytic bacteriophage was isolated from sewage samples obtained from a local aquatic market. Morphological analysis revealed that the phage, designated as PVA1, belonged to the family Podoviridae. The complete genomic sequence of phage PVA1 contained 41,529 bp with a G + C content of 43.7 % and 75 putative open reading frames. The genome was grouped into four modules, including phage structure, DNA packaging, DNA replication and regulation, and some additional functions. Further genomic comparison of the phage PVA1 with other known phages showed no significant similarities. Genes related to virulence and lysogeny were not detected in the phage genome. Our results suggest that phage PVA1 may be classified as a new Vibrio phage. We believe that these phage genomic sequence data will provide useful basic information for further molecular research on this Vibrio phage and its host as well for determining its infection/interaction mechanisms.
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Femtosecond time-resolved transient absorption spectroscopy of CH3NH3PbI3 perovskite films: evidence for passivation effect of PbI2.
J. Am. Chem. Soc.
PUBLISHED: 08-22-2014
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CH3NH3PbI3 perovskite layered films deposited on substrates with and without a titania support structure have been prepared and studied using time-resolved femtosecond transient absorption (fs-TA) spectroscopy in the visible light range (450-800 nm). The electron injection dynamics from the photoexcited perovskite layers to the neighboring film structures could be directly monitored via the transient bleaching dynamics of the perovskite at ?750 nm and thus systematically studied as a function of the layer-by-layer architecture. In addition, for the first time we could spectrally distinguish transient bleaching at ?750 nm from laser-induced fluorescence that occurs red-shifted at ?780 nm. We show that an additional bleach feature at ?510 nm appears when PbI2 is present in the perovskite film. The amplitudes of the PbI2 and perovskite TA peaks were compared to estimate relative amounts of PbI2 in the samples. Kinetic analysis reveals that perovskite films with less PbI2 show faster relaxation rates than those containing more PbI2. These fast dynamics are attributed to charge carrier trapping at perovskite grain boundaries, and the slower dynamics in samples containing PbI2 are due to a passivation effect, in line with other recently reported work.
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High temperature superconducting FeSe films on SrTiO3 substrates.
Sci Rep
PUBLISHED: 08-12-2014
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Interface enhanced superconductivity at two dimensional limit has become one of most intriguing research directions in condensed matter physics. Here, we report the superconducting properties of ultra-thin FeSe films with the thickness of one unit cell (1-UC) grown on conductive and insulating SrTiO3 (STO) substrates. For the 1-UC FeSe on conductive STO substrate (Nb-STO), the magnetization versus temperature (M-T) measurement shows a drop crossover around 85 K. For the FeSe films on insulating STO substrate, systematic transport measurements were carried out and the sheet resistance of FeSe films exhibits Arrhenius TAFF behavior with a crossover from a single-vortex pinning region to a collective creep region. More intriguing, sign reversal of Hall resistance with temperature is observed, demonstrating a crossover from hole conduction to electron conduction above TC in 1-UC FeSe films.
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Receptor usage and cell entry of bat coronavirus HKU4 provide insight into bat-to-human transmission of MERS coronavirus.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 08-11-2014
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Middle East respiratory syndrome coronavirus (MERS-CoV) currently spreads in humans and causes ? 36% fatality in infected patients. Believed to have originated from bats, MERS-CoV is genetically related to bat coronaviruses HKU4 and HKU5. To understand how bat coronaviruses transmit to humans, we investigated the receptor usage and cell entry activity of the virus-surface spike proteins of HKU4 and HKU5. We found that dipeptidyl peptidase 4 (DPP4), the receptor for MERS-CoV, is also the receptor for HKU4, but not HKU5. Despite sharing a common receptor, MERS-CoV and HKU4 spikes demonstrated functional differences. First, whereas MERS-CoV prefers human DPP4 over bat DPP4 as its receptor, HKU4 shows the opposite trend. Second, in the absence of exogenous proteases, both MERS-CoV and HKU4 spikes mediate pseudovirus entry into bat cells, whereas only MERS-CoV spike, but not HKU4 spike, mediates pseudovirus entry into human cells. Thus, MERS-CoV, but not HKU4, has adapted to use human DPP4 and human cellular proteases for efficient human cell entry, contributing to the enhanced pathogenesis of MERS-CoV in humans. These results establish DPP4 as a functional receptor for HKU4 and host cellular proteases as a host range determinant for HKU4. They also suggest that DPP4-recognizing bat coronaviruses threaten human health because of their spikes' capability to adapt to human cells for cross-species transmissions.
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The prognostic value of serum pregnancy-associated plasma protein A, S100 and high sensitivity C-reactive protein in acute ischemic stroke patients without heparin administration.
Clin. Biochem.
PUBLISHED: 08-10-2014
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The concerns regarding the pre-analytical bias caused by medicine treatments have been raised in the diagnosis and prognosis of ischemic stroke recently. The aim of this study was to examine the prognostic value of serum pregnancy-associated plasma protein A (PAPP-A), S100 and high sensitivity C-reactive protein (hs-CRP) in heparin-naïve patients of acute ischemic stroke.
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A flexible pinhole camera model for coherent nonuniform sampling.
IEEE Comput Graph Appl
PUBLISHED: 07-23-2014
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The flexible pinhole camera (FPC) allows flexible modulation of the sampling rate over the field of view. The FPC is defined by a viewpoint and a map specifying the sampling locations on the image plane. The map is constructed from known regions of interest with interactive and automatic approaches. The FPC provides inexpensive 3D projection that allows rendering complex datasets quickly, in feed-forward fashion, by projection followed by rasterization. The FPC supports many types of data, including image, height field, geometry, and volume data. The resulting image is a coherent nonuniform sampling (CoNUS) of the dataset that matches the local variation of the dataset's importance. CoNUS images have been successfully implemented for remote visualization, focus-plus-context visualization, and acceleration of expensive rendering effects such as surface geometric detail and specular reflection. A video explaining and demonstrating the FPC is at http://youtu.be/kvFe5XjOPNM.
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Design of a simultaneous target and location-activatable fluorescent probe for visualizing hydrogen sulfide in lysosomes.
Anal. Chem.
PUBLISHED: 07-14-2014
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Molecular tools capable of providing information on a target analyte in an organelle of interest are especially appreciated. Traditionally, organelle-targetable probes are designed by incorporating an organelle-specific guiding unit to target the probe molecules into the organelle. The imperfect targeting function of the guiding unit and nonspecific distribution of the analyte in cytosol and each organelle would lead to low spatiotemporal resolution and limited sensitivity. To solve this problem, we report herein a new approach for detection of a target analyte in a specific organelle by engineering a target and location dual-controlled molecular switch. For this proof-of-concept study, fluorescent detection of H2S in lysosomes was performed with a simultaneous H2S and proton-activatable probe based on the acidic environment of lysosomes. The new synthesized fluorescent sensor, "SulpHensor", which contains a spirolactam moiety to bind hydrogen protons and an azide group to react with H2S, displays highly sensitive and selective fluorescence response to H2S under lysosomal pH environment but is out of operation in neutral cytosol and other organelles. Fluorescence imaging shows that SulpHensor is membrane-permeable and suitable for visualization of both the exogenous and endogenous H2S in lysosomes of living cells. The good performance of our proposed approach for H2S sensing demonstrates that this strategy might open up new opportunities for the development of efficient subcellular molecular tools for bioanalytical and biomedical applications.
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Refolding and simultaneous purification of recombinant human proinsulin from inclusion bodies on protein-folding liquid-chromatography columns.
Biomed. Chromatogr.
PUBLISHED: 07-09-2014
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Protein-folding liquid chromatography (PFLC) is an effective and scalable method for protein renaturation with simultaneous purification. However, it has been a challenge to fully refold inclusion bodies in a PFLC column. In this work, refolding with simultaneous purification of recombinant human proinsulin (rhPI) from inclusion bodies from Escherichia coli were investigated using the surface of stationary phases in immobilized metal ion affinity chromatography (IMAC) and high-performance size-exclusion chromatography (HPSEC). The results indicated that both the ligand structure on the surface of the stationary phase and the composition of the mobile phase (elution buffer) influenced refolding of rhPI. Under optimized chromatographic conditions, the mass recoveries of IMAC column and HPSEC column were 77.8 and 56.8% with purifies of 97.6 and 93.7%, respectively. These results also indicated that the IMAC column fails to refold rhPI, and the HPSEC column enables efficient refolding of rhPI with a low-urea gradient-elution method. The refolded rhPI was characterized by circular dichroism spectroscopy. The molecular weight of the converted human insulin was further confirmed with SDS-18% PAGE, Matrix-Assisted Laser Desorption/ Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) and the biological activity assay by HP-RPLC. Copyright © 2014 John Wiley & Sons, Ltd.
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Identification of rice Di19 family reveals OsDi19-4 involved in drought resistance.
Plant Cell Rep.
PUBLISHED: 07-01-2014
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The OsDi19 proteins functioned as transcription factors and played crucial roles in response to abiotic stress. Overexpression of OsDi19 - 4 in rice increased drought tolerance by enhancing ROS-scavenging activity. Many transcription factors play crucial roles in plant responses to abiotic stress. Here, comprehensive sequence analysis suggested that the drought-induced 19 (Di19) gene family in rice genome contain seven members, and these proteins contained a well-conserved zinc-finger Di19 domain. Most OsDi19 proteins were mainly targeted to the nucleus and have transactivation activity in yeast. Yeast two-hybrid and bimolecular fluorescence complementation assays showed that most OsDi19 proteins could form protein dimers. Expression analysis demonstrated that the OsDi19 genes were differentially and abundantly expressed in vegetative tissues, but expressed little in reproductive tissues and some of the OsDi19 genes were markedly induced by abiotic stresses and hormones in qRT-PCR analysis and microarray data. Overexpression of one stress-responsive gene, OsDi19-4, in rice resulted in significantly increased tolerance to drought stress compared with the wild type plants. Moreover, obviously increased ROS-scavenging ability was detected in the OsDi19-4-overexpressing plants under normal and drought stress conditions. These results suggested that the increased stress tolerance of OsDi19-4-overexpressing plants may be attributable to the enhanced ROS-scavenging activity. Taken together, these studies provide a detailed overview of the rice Di19 gene family, and suggest that the OsDi19 family may play crucial roles in the plant response to abiotic stress.
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Clinical analysis of six cases of multiple myeloma first presenting with coagulopathy.
Blood Coagul. Fibrinolysis
PUBLISHED: 07-01-2014
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This is a retrospective study on six multiple myeloma patients with upfront coagulopathy and bleeding. A detailed description and analysis of clinical characteristics, coagulation factor deficiencies, treatments and outcome of those six multiple myeloma patients are presented. All six patients presented with significant bleeding. One patient was detected with single factor X deficiency and another with single factor VII (FVII) deficiency, whereas four other patients had complex factor deficiencies. The time from symptom presentation to diagnosis ranged from 3 to 10 months. After correct diagnosis and coagulation factor supplementation, those patients were treated with bortezomib/adriamycin/dexamethasone (PAD) or melphalan/dexamethasone/thalidomide (MTD) regimen. It took 29-71 days (median time 46 days) to completely correct coagulation factor deficiencies since the start of therapy for multiple myeloma. Multiple myeloma patients with acquired bleeding disorders may present with large, deep and multiple sites of haematoma or other types of significant bleeding, which may affect bone marrow examination in some of the cases. Patients may be easily misdiagnosed. The routine examinations of erythrocyte sedimentation rate, serum immunoglobulins and blood urine light chain are the key to diagnosis, hence requiring the treating physician to think broadly and look for traits suggesting myeloma as the underlying cause.
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L312, a novel PPAR? ligand with potent anti-diabetic activity by selective regulation.
Biochim. Biophys. Acta
PUBLISHED: 06-24-2014
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Selective PPAR? modulators (sPPAR?M) retains insulin sensitizing activity but with minimal side effects compared to traditional TZD agents, is thought as a promising strategy for development of safer insulin sensitizer.
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Protoplast: a more efficient system to study nucleo-cytoplasmic interactions.
Biochem. Biophys. Res. Commun.
PUBLISHED: 06-24-2014
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Agrobacterium tumefaciens-mediated genetic transformation is a powerful tool for plant research, but it can be labor-intensive and time-consuming. Here, we report a protoplast-based approach to study nucleo-cytoplasmic interactions, such as cytoplasmic male sterility/fertility restoration (CMS/Rf) and organellar RNA editing. To test the system, we transfected the fertility restorer gene Rf5, which is involved in the rice HL-CMS/Rf system, into rice protoplasts prepared from the HL-CMS line. As the Rf5 protein accumulated in the transformed protoplasts, the CMS-associated transcripts were endonucleolytically cleaved. There were much lower levels of the CMS-associated protein ORFH79 in the transfected protoplasts than in the mock-transfected protoplasts. Next, we used a dsRNA-mediated gene silencing approach to down-regulate the pentatricopeptide protein gene MPR25, which participates in RNA editing of the organellar transcript nad5. The editing efficiency of mitochondrial transcripts of nad5 at nucleotide 1580 was much lower in the transfected protoplasts than in the mock-transfected protoplasts. Together, these results show that protoplast is a simple and efficient system to study interactions between the nucleus and organelles.
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Sodium channels, cardiac arrhythmia, and therapeutic strategy.
Adv. Pharmacol.
PUBLISHED: 06-17-2014
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Cardiac sodium channels are transmembrane proteins distributed in atrial and ventricular myocytes and Purkinje fibers. A large and rapid Na(+) influx through these channels initiates action potential and thus excitation-contraction coupling of cardiac cells. Cardiac sodium channel is composed of a pore-forming ?-subunit and one or two accessory ?-subunits. The cardiac ?-subunit is encoded by gene SCN5A located on chromosome 3p21. There are four types of ?-subunits identified so far, and ?1 is the primary ?-subunit in cardiac Na(+) channels. The gene responsible for ?1 subunits is SCNB. The expression of ?-subunits together with ? subunits enhances the Na(+) current and modifies the channel activities. In addition, interactions of the cardiac Na(+) channel with other proteins may facilitate the channel activity and membrane expression of the channel. Over the past two decades, molecular genetic studies have identified the linkage of gene mutations of the Na(+) channel proteins and other regulatory proteins to many inherited arrhythmogenic diseases. The most common cardiac arrhythmogenic diseases associated with Na(+) channelopathies are long QT syndrome (LQT3) and Brugada syndromes (BrSs). This chapter intends to summarize the current understanding of the normal sodium-channel structure and function, the gene mutation-associated cardiac arrhythmias, and the current diagnosis and management of these diseases.
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Energy barrier at the N719-dye/CsSnI3 interface for photogenerated holes in dye-sensitized solar cells.
Sci Rep
PUBLISHED: 06-16-2014
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This report is to address the question if black ?-polymorph of cesium tin tri-iodide (B-?-CsSnI3) can be used as a solid-state hole-transport material in the conventional DSSCs with the N719 dye to replace the liquid electrolyte as reported by I. Chung et al. on Nature 485, 486, (2012). Here we demonstrate rigorously that B-?-CsSnI3 is not energetically possible to collect photogenerated holes because of the large energy barrier at the interface of N719/B-?-CsSnI3. Therefore, it cannot serve as a hole-transporter for the conventional DSSCs although it is a good hole-conducting material. A solution-based method was employed to synthesize the B-?-CsSnI3 polycrystalline thin-films used for this work. These thin-films were then characterized by X-ray diffraction, Hall measurements, optical reflection, and photoluminescence (PL). Particularly, spatially resolved PL intensity images were taken after B-?-CsSnI3 was incorporated in the DSSC structure to insure the material integrity. The means of ultraviolet photoemission spectroscopy (UPS) was used to reveal why B-?-CsSnI3 could not act as the substitute of liquid electrolyte in the conventional DSSCs. For the completeness, other two related compounds, one is the yellow polymorph of CsSnI3 and other is Cs2SnI6 with tetravalent tin instead of double-valent tin in CsSnI3 were also investigated by UPS.
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Genetic variation of human respiratory syncytial virus among children with fever and respiratory symptoms in Shanghai, China, from 2009 to 2012.
Infect. Genet. Evol.
PUBLISHED: 06-14-2014
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Human respiratory syncytial virus (HRSV) of genus Pneumovirus is one of the most common pathogens causing severe acute lower respiratory tract infection in infants and children. No information on the genotype distribution of HRSV is available in East China (e.g. Shanghai). From August 2009 to December 2012, 2407 nasopharyngeal swabs were collected from outpatient children with fever and respiratory symptoms in Shanghai. HRSV infection was determined using a multiplex RT-PCR assay. The second hypervariable region (HVR2) of G protein gene of HRSV was amplified and sequenced from HRSV positive samples. Genotypes were characterized by phylogenetic analyses. Of 2407 nasopharyngeal samples, 184 (7.6%) were tested as HRSV positive. From 160 positive subjects with sufficient nasopharyngeal samples, 69 HVR2 sequences were obtained by RT-PCR and sequencing. Three HRSV epidemic seasons were observed from August 2009 to December 2012, and an extreme outbreak of HRSV occurred in the 2009-2010 epidemic season. A genotype shift of predominant HRSV strains from B group in the 2009-2010 epidemic season to group A in the subsequent epidemic seasons was observed. Ten HRSV genotypes, including four group A genotypes NA1, NA3, NA4, and ON1, and six group B genotypes BA9, BA10, SAB4, CB1, BAc, and BA?, were detected in Shanghai. Seven genotypes (NA1, BA9-10, SAB4, CB1, BAc and BA?) were found in the 2009-2010 epidemic season. The co-circulation of multiple genotypes was associated with the extreme outbreak of HRSV among children with fever and respiratory symptoms in the 2009-2010 epidemic season.
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Combination of Optical and Electrical Loss Analyses for a Si-Phthalocyanine Dye-Sensitized Solar Cell.
J Phys Chem B
PUBLISHED: 06-13-2014
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In order to promote the development of solar cells with varying types of sensitizers including dyes and quantum dots, it is crucial to establish a general experimental analysis that accounts for all important optical and electrical losses resulting from interfacial phenomena. All of these varying types of solar cells share common features where a mesoporous scaffold is used as a sensitizer loading support as well as an electron transport material, which may result in light scattering. The loss of efficiency at interfaces of the sensitizer, the mesoporous TiO2 nanoparticle films, the FTO conductive layer, and the supportive glass substrate should be considered in addition to the photoinduced electron transport properties within a cell. On the basis of optical parameters, one can obtain the internal quantum efficiency (IQE) of a solar cell, an important parameter that cannot be directly measured but must be derived from several key experiments. By integrating an optical loss model with an electrical loss model, many solar cell parameters could be characterized from electro-optical observables including reflectance, transmittance, and absorptance of the dye sensitizer, the electron injection efficiency, and the charge collection efficiency. In this work, an integrated electro-optical approach has been applied to SiPc (Pc 61) dye-sensitized solar cells for evaluating the parameters affecting the overall power conversion efficiency. The absorptance results of the Pc 61 dye-sensitized solar cell provide evidence that the adsorbed Pc 61 forms noninjection layers on TiO2 surfaces when the dye immersion time exceeds 120 min, resulting in shading light from the active layer rather than an increase in photoelectric current efficiency.
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Toward the development of the potential with angular distortion for halogen bond: a comparison of potential energy surfaces between halogen bond and hydrogen bond.
J Phys Chem A
PUBLISHED: 06-09-2014
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As noncovalent intermolecular interactions, hydrogen bond (HB) and halogen bond (XB) are attracting increasing attention. In this work, the potential energy surfaces (PESs) of hydrogen and halogen bonds are compared. Twelve halogen-bonded and three hydrogen-bonded models are scanned for analysis using the MP2 level of theory. This work indicates that potential energy surfaces of both HB and XB have angular distortion. The potential well of XB is narrower than that of HB. With the elongation of the bond length, the potential energy surfaces get flatter. The best fitting functions for angular distortion and the flattening character of angular terms are also combined into a modified Buckingham potential. The testing results show that the essential features of the PES, including angular distortion and flattening character, have been reproduced. These results provide a better understanding of halogen and hydrogen bonds and the optimization of halogen bond force fields.
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Electrically tuned magnetic order and magnetoresistance in a topological insulator.
Nat Commun
PUBLISHED: 06-08-2014
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The interplay between topological protection and broken time reversal symmetry in topological insulators may lead to highly unconventional magnetoresistance behaviour that can find unique applications in magnetic sensing and data storage. However, the magnetoresistance of topological insulators with spontaneously broken time reversal symmetry is still poorly understood. In this work, we investigate the transport properties of a ferromagnetic topological insulator thin film fabricated into a field effect transistor device. We observe a complex evolution of gate-tuned magnetoresistance, which is positive when the Fermi level lies close to the Dirac point but becomes negative at higher energies. This trend is opposite to that expected from the Berry phase picture, but is intimately correlated with the gate-tuned magnetic order. The underlying physics is the competition between the topology-induced weak antilocalization and magnetism-induced negative magnetoresistance. The simultaneous electrical control of magnetic order and magnetoresistance facilitates future topological insulator based spintronic devices.
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Matrix softness regulates plasticity of tumour-repopulating cells via H3K9 demethylation and Sox2 expression.
Nat Commun
PUBLISHED: 06-06-2014
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Tumour-repopulating cells (TRCs) are a self-renewing, tumorigenic subpopulation of cancer cells critical in cancer progression. However, the underlying mechanisms of how TRCs maintain their self-renewing capability remain elusive. Here we show that relatively undifferentiated melanoma TRCs exhibit plasticity in Cdc42-mediated mechanical stiffening, histone 3 lysine residue 9 (H3K9) methylation, Sox2 expression and self-renewal capability. In contrast to differentiated melanoma cells, TRCs have a low level of H3K9 methylation that is unresponsive to matrix stiffness or applied forces. Silencing H3K9 methyltransferase G9a or SUV39h1 elevates the self-renewal capability of differentiated melanoma cells in a Sox2-dependent manner. Mechanistically, H3K9 methylation at the Sox2 promoter region inhibits Sox2 expression that is essential in maintaining self-renewal and tumorigenicity of TRCs both in vitro and in vivo. Taken together, our data suggest that 3D soft-fibrin-matrix-mediated cell softening, H3K9 demethylation and Sox2 gene expression are essential in regulating TRC self-renewal.
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New method for the visual detection of human respiratory syncytial virus using reverse transcription loop-mediated amplification.
J. Virol. Methods
PUBLISHED: 05-28-2014
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Human respiratory syncytial virus (HRSV) is a seasonal respiratory pathogen that causes respiratory infection in children and the elderly. A new, reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay was developed for the rapid (within 1h), simultaneous detection of A and B group HRSV. Primers specific for groups A and B were designed to amplify the N and L genes of HRSV, respectively. A fluorescent dye, calcein, was used as an indicator for the endpoint visual detection and/or real-time amplification of HRSV RNA. The detection limit of the new method was 281.17 50% tissue culture infective doses (TCID50)/ml for HRSV A and 1.58 TCID50/ml for HRSV B. To evaluate the validity of this method, a comparison with RT-PCR was performed using 77 nasopharyngeal swabs as samples. Both RT-LAMP and RT-PCR detected HRSV in 38 HRSV samples, yielding a positive rate of 49%. Of the RT-LAMP positive samples, 36 (95%) were also positive by RT-PCR, while two were negative by RT-PCR. Among the 36 RT-LAMP and RT-PCR positive samples, 11 belonged to HRSV group A, while 25 belonged to group B. The results show that the new RT-LAMP is simple, rapid and well suited for HRSV diagnosis, especially in a limited-resource setting.
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Molecular beam epitaxy growth and post-growth annealing of FeSe films on SrTiO3: a scanning tunneling microscopy study.
J Phys Condens Matter
PUBLISHED: 05-28-2014
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Low temperature scanning tunneling microscopy and spectroscopy are used to investigate the atomic and electronic structure evolution of FeSe films grown on SrTiO3 as a function of post-growth annealing. Single unit cell FeSe films are found to bond strongly with the underlying substrate, and become superconductive with diminishing chemical bond disorders at the interface via post-annealing. For thicker FeSe films, post-annealing removes excess Se in the films and leads to a transition from semiconductor into metallic behaviors. In double and multilayer films, strain-induced complex textures are observed and suggested to be the main cause for the absent superconductivity.
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Searching for an ideal vaccine candidate among different MERS coronavirus receptor-binding fragments-The importance of immunofocusing in subunit vaccine design.
Vaccine
PUBLISHED: 05-25-2014
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The newly emerged Middle East respiratory syndrome coronavirus (MERS-CoV) is currently spreading among humans, making development of effective MERS vaccines a high priority. A defined receptor-binding domain (RBD) in MERS-CoV spike protein can potentially serve as a subunit vaccine candidate against MERS-CoV infections. To identify an ideal vaccine candidate, we have constructed five different versions of RBD fragments, S350-588-Fc, S358-588-Fc, S367-588-Fc, S367-606-Fc, and S377-588-Fc (their names indicate their residue range in the spike protein and their C-terminal Fc tag), and further investigated their receptor binding affinity, antigenicity, immunogenicity, and neutralizing potential. The results showed that S377-588-Fc is among the RBD fragments that demonstrated the highest DPP4-binding affinity and induced the highest-titer IgG antibodies in mice. In addition, S377-588-Fc elicited higher-titer neutralizing antibodies than all the other RBD fragments in mice, and also induced high-titer neutralizing antibodies in immunized rabbits. Structural analysis suggests that S377-588-Fc contains the stably folded RBD structure, the full receptor-binding site, and major neutralizing epitopes, such that additional structures to this fragment introduce non-neutralizing epitopes and may also alter the tertiary structure of the RBD. Taken together, our data suggest that the RBD fragment encompassing spike residues 377-588 is a critical neutralizing receptor-binding fragment and an ideal candidate for development of effective MERS vaccines, and that adding non-neutralizing structures to this RBD fragment diminishes its neutralizing potential. Therefore, in viral vaccine design, it is important to identify the most stable and neutralizing viral RBD fragment, while eliminating unnecessary and non-neutralizing structures, as a means of "immunofocusing".
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[Outcomes of percutaneous coronary intervention for intermediate coronary artery disease guided by intravascular ultrasound or fractional flow reserve].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 05-23-2014
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To evaluate the long-term clinical outcomes of fractional flow reserve (FFR)-guided versus intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) for intermediate coronary lesions.
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The E3 ligase RNF34 is a novel negative regulator of the NOD1 pathway.
Cell. Physiol. Biochem.
PUBLISHED: 05-14-2014
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To identify the regulator of nucleotide-binding oligomerization domain-containing protein 1 (NOD1) and its regulatory function.
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Experimental observation of Dirac-like surface states and topological phase transition in Pb(1-x)Sn(x)Te(111) films.
Phys. Rev. Lett.
PUBLISHED: 05-05-2014
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The surface of a topological crystalline insulator (TCI) carries an even number of Dirac cones protected by crystalline symmetry. We epitaxially grew high-quality Pb(1-x)Sn(x)Te(111) films and investigated the TCI phase by in situ angle-resolved photoemission spectroscopy. Pb(1-x)Sn(x)Te(111) films undergo a topological phase transition from a trivial insulator to TCI via increasing the Sn/Pb ratio, accompanied by a crossover from n-type to p-type doping. In addition, a hybridization gap is opened in the surface states when the thickness of the film is reduced to the two-dimensional limit. The work demonstrates an approach to manipulating the topological properties of TCI, which is of importance for future fundamental research and applications based on TCI.
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Generation of organized germ layers from a single mouse embryonic stem cell.
Nat Commun
PUBLISHED: 04-29-2014
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Mammalian inner cell mass cells undergo lineage-specific differentiation into germ layers of endoderm, mesoderm and ectoderm during gastrulation. It has been a long-standing challenge in developmental biology to replicate these organized germ layer patterns in culture. Here we present a method of generating organized germ layers from a single mouse embryonic stem cell cultured in a soft fibrin matrix. Spatial organization of germ layers is regulated by cortical tension of the colony, matrix dimensionality and softness, and cell-cell adhesion. Remarkably, anchorage of the embryoid colony from the 3D matrix to collagen-1-coated 2D substrates of ~1?kPa results in self-organization of all three germ layers: ectoderm on the outside layer, mesoderm in the middle and endoderm at the centre of the colony, reminiscent of generalized gastrulating chordate embryos. These results suggest that mechanical forces via cell-matrix and cell-cell interactions are crucial in spatial organization of germ layers during mammalian gastrulation. This new in vitro method could be used to gain insights on the mechanisms responsible for the regulation of germ layer formation.
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A unique semiconductor-metal-graphene stack design to harness charge flow for photocatalysis.
Adv. Mater. Weinheim
PUBLISHED: 04-22-2014
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A novel semiconductor-metal-graphene stack design, which reduces interfacial defect density as well as provides channels for charge transport, has been demonstrated to harness the charge flow for efficient electron-hole separation. As a direct outcome, the designed hybrid structures exhibit significantly improved performance in photocatalytic hydrogen production from water.
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Seasonal and diurnal variation in particulate matter (PM10 and PM 2.5) at an urban site of Beijing: analyses from a 9-year study.
Environ Sci Pollut Res Int
PUBLISHED: 04-03-2014
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Air pollution has become a top environmental concern in China. In the present study, 9 years of PM10 and PM2.5 data from an urban monitoring station in Beijing was analyzed relative to other gaseous pollutants and several meteorological parameters. The levels and characteristics of particulate matters as well as the sources and factors affecting them were provided in the present study. During the 9-year observation period, PM10 and PM2.5 showed high levels, with annual mean values of 138.5?±?92.9 and 72.3?±?54.4 ?g/m(3), respectively. Slight decreasing trends of annual mean PM10 and PM2.5 were observed; autumn was the main season that contributed to the decrease in annual mean PM10 and PM2.5. Higher values for both PM fractions were generally observed in the spring and summer months, respectively, whereas lower values were found in the summer and spring months, respectively. Pronounced diurnal variations were found for PM10 and PM2.5, which both displayed a bimodal pattern with peaks between 7:00 and 8:00 a.m. as well as 7:00 and 11:00 p.m.; a minimum generally appeared at approximately noon. The seasonal and diurnal variations in particulate concentration are mostly dominated by the seasonal and diurnal variability of boundary layer and source emissions. A principal components analysis revealed that both the traffic-related emissions and combustion sources were major contributions to the particles; their contributions ranged between 35.5-75.1 %. Furthermore, a directional analysis shows a stronger association between particles and the southerly winds, the PM derived from sources south of Beijing, most likely secondary PM, significantly affects concentrations at the sampling site. To improve air quality in Beijing, mitigation measures including phasing out high energy-consuming industries and prioritize the use of clean energy sources should be designed to reduce emissions from both local and regional sources.
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Alagebrium (ALT-711) improves the anti-hypertensive efficacy of nifedipine in diabetic-hypertensive rats.
Hypertens. Res.
PUBLISHED: 03-23-2014
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Combining drugs with complementary mechanisms of action may contribute to improved hypertension control in diabetic patients. Advanced glycation end-product (AGE) breakers, a new class of candidate drugs targeting aging-related cardiovascular dysfunction, may be useful as novel adjuvant agents to improve the efficacy of diabetic hypertension (DH) treatment. This study evaluated the effects of alagebrium (ALT-711), an AGE breaker, combined with nifedipine, a Ca(2+) channel blocker, in a rat model of streptozotocin-induced DH. Compared with monotherapy, combination treatment significantly decreased systolic and diastolic blood pressure values, increased the pulse pressure, and decreased the coefficient of variation of the systolic blood pressure. Plasma biochemistry indicated that the concentrations of prostacyclin and nitric oxide were increased. Gene expression analysis showed significantly decreased prepro-endothelin-1expression in the aorta. These results reveal that alagebrium significantly improves the anti-hypertensive actions of nifedipine in a rat model of DH and suggest its potential use in the successful control of clinical DH.
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Discovery of potent anticancer agent HJC0416, an orally bioavailable small molecule inhibitor of signal transducer and activator of transcription 3 (STAT3).
Eur J Med Chem
PUBLISHED: 03-10-2014
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In a continuing effort to develop orally bioavailable small-molecule STAT3 inhibitors as potential therapeutic agents for human cancer, a series of novel diversified analogues based on our identified lead compound HJC0149 (1) (5-chloro-N-(1,1-dioxo-1H-1?(6)-benzo[b]thiophen-6-yl)-2-hydroxybenzamide, Eur. J. Med. Chem. 2013, 62, 498-507) have been rationally designed, synthesized, and pharmacologically evaluated. Molecular docking studies and biological characterization supported our earlier findings that the O-alkylamino-tethered side chain on the hydroxyl group is an effective and essential structural determinant for improving biological activities and druglike properties of these molecules. Compounds with such modifications exhibited potent antiproliferative effects against breast and pancreatic cancer cell lines with IC50 values from low micromolar to nanomolar range. Among them, the newly discovered STAT3 inhibitor 12 (HJC0416) displayed an intriguing anticancer profile both in vitro and in vivo (i.p. & p.o.). More importantly, HJC0416 is an orally bioavailable anticancer agent as a promising candidate for further development.
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One-step refolding and purification of recombinant human tumor necrosis factor-? (rhTNF-?) using ion-exchange chromatography.
Biomed. Chromatogr.
PUBLISHED: 03-02-2014
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Protein refolding is a key step for the production of recombinant proteins, especially at large scales, and usually their yields are very low. Chromatographic-based protein refolding techniques have proven to be superior to conventional dilution refolding methods. High refolding yield can be achieved using these methods compared with dilution refolding of proteins. In this work, recombinant human tumor necrosis factor-? (rhTNF-?) from inclusion bodies expressed in Escherichia coli was renatured with simultaneous purification by ion exchange chromatography with a DEAE Sepharose FF column. Several chromatographic parameters influencing the refolding yield of the denatured/reduced rhTNF-?, such as the urea concentration, pH value and concentration ratio of glutathione/oxidized glutathione in the mobile phase, were investigated in detail. Under optimal conditions, rhTNF-? can be renatured and purified simultaneously within 30 min by one step. Specific bioactivity of 2.18?×?10(8) IU/mg, purity of 95.2% and mass recovery of 76.8% of refolded rhTNF-? were achieved. Compared with the usual dilution method, the ion exchange chromatography method developed here is simple and more effective for rhTNF-? refolding in terms of specific bioactivity and mass recovery. Copyright © 2014 John Wiley & Sons, Ltd.
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Acetone-Butanol-Ethanol competitive sorption simulation from single, binary and ternary systems in a fixed-bed of KA-I resin.
Biotechnol. Prog.
PUBLISHED: 02-26-2014
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Separation of butanol based on sorption methodology from Acetone - Butanol - Ethanol (ABE) fermentation broth has advantages in terms of biocompatibility and stability, as well as economy, and therefore gains much attention. In this work a chromatographic column model based on the solid film linear driving force approach and the competitive Langmuir isotherm equations was used to predict the competitive sorption behaviors of ABE single, binary and ternary mixture. It was observed that the outlet concentration of weaker retained components exceeded the inlet concentration, which is an evidence of competitive adsorption. Butanol, the strongest retained component, could replace ethanol almost completely and also most of acetone. In the end of this work, the proposed model was validated by comparison of the experimental and predicted ABE ternary breakthrough curves using the real ABE fermentation broth as a feed solution. This article is protected by copyright. All rights reserved.
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Serum microRNA expression signatures identified from genome-wide microRNA profiling serve as novel noninvasive biomarkers for diagnosis and recurrence of bladder cancer.
Int. J. Cancer
PUBLISHED: 02-24-2014
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Recent advantages of serum microRNAs (miRNAs) open a new realm of possibilities for noninvasive diagnosis and prognosis of bladder cancer (BC). The aim of our study was to identify serum miRNA expression signatures in patients with BC and establish new models for the diagnosis of BC and recurrence prediction. We performed genome-wide serum miRNA analysis by Miseq sequencing followed by evaluations in the training and validation sets with reverse transcription quantitative real-time PCR assays from serum samples of 250 patients with BC and 240 controls. A six-miRNA panel (miR-152, miR-148b-3p, miR-3187-3p, miR-15b-5p, miR-27a-3p and miR-30a-5p) for the diagnosis of BC was finally developed by multivariate logistic regression model with an area under the receiver operating characteristic curve of 0.899. The corresponding sensitivities of this panel for Ta, T1 and T2-T4 were 90.00, 84.85 and 89.36%, significantly higher than those of urine cytology, which were 13.33, 30.30 and 44.68%, respectively (all at p?
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Dichotomy of the electronic structure and superconductivity between single-layer and double-layer FeSe/SrTiO3 films.
Nat Commun
PUBLISHED: 02-14-2014
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The latest discovery of possible high-temperature superconductivity in the single-layer FeSe film grown on a SrTiO3 substrate has generated much attention. Initial work found that, while the single-layer FeSe/SrTiO3 film exhibits a clear signature of superconductivity, the double-layer film shows an insulating behaviour. Such a marked layer-dependent difference is surprising and the underlying origin remains unclear. Here we report a comparative angle-resolved photoemission study between the single-layer and double-layer FeSe/SrTiO3 films annealed in vacuum. We find that, different from the single-layer FeSe/SrTiO3 film, the double-layer FeSe/SrTiO3 film is hard to get doped and remains in the semiconducting/insulating state under an extensive annealing condition. Such a behaviour originates from the much reduced doping efficiency in the bottom FeSe layer of the double-layer FeSe/SrTiO3 film from the FeSe-SrTiO3 interface. These observations provide key insights in understanding the doping mechanism and the origin of superconductivity in the FeSe/SrTiO3 films.
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Giant keratocystic odontogenic tumor of the maxillary sinus and zygoma: A case report.
Oncol Lett
PUBLISHED: 02-06-2014
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Keratocystic odontogenic tumors (KCOTs), formally known as odontogenic keratocysts, are benign developmental tumors that are found primarily in the mandibular molar region and ascending ramus. The disease is characterized by aggressive growth and a high recurrence rate following surgical treatment. The present study reports the rare case of a 25-year-old male with a giant KCOT involving the right zygoma, maxillary bone and maxillary sinus. The tumor was removed using a modified treatment of enucleation, grinding and cryotherapy. Recurrence has not been observed within the eight-month follow-up period. The present study discusses the clinical features and surgical management of this case.
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Persistent detection of avian influenza A/H7N9 virus among poultry in Huzhou City, China, in the summer of 2013.
Int. J. Infect. Dis.
PUBLISHED: 01-20-2014
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In eastern China, live poultry markets were successively re-opened in the summer of 2013 following their closure in April 2013. We detected influenza A/H7N9 RNA with positive rates from 4% to 22.2% among poultry samples in targeted markets in Huzhou City, China, from August 6 to September 24, 2013. Phylogenetic analyses of hemagglutinin and neuraminidase genes confirmed that the strain prevalent among poultry in Huzhou City in the summer of 2013 belonged to the same genotype as those capable of infecting humans. These results raise concern for a further outbreak of H7N9 in the cooler season.
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High expression of miR-21 in triple-negative breast cancers was correlated with a poor prognosis and promoted tumor cell in vitro proliferation.
Med. Oncol.
PUBLISHED: 01-06-2014
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The triple-negative breast cancer (TNBC), with a particularly poor prognosis, is increasingly recognized as heterogeneous in molecular signatures. MicroRNA expression profiles have been used for the classification and prognostication of breast cancer, numerous significantly upregulated microRNAs, i.e. miR-21, have been verified oncogenic in non-TNBCs. In present study, we determined the miR-21 levels in TNBC specimens, and TNBC cell levels in vitro, and then identified the role of miR-21 on tumor cell proliferation, apoptosis, and then identified PTEN as the possible target of the microRNA. It was shown that miR-21 expression is upregulated generally, and heterogeneous in TNBC specimens, posing a correlation with poor prognosis for TNBC patients. Further results demonstrated that the upregulated miR-21 promoted the tumor proliferation and inhibited cell apoptosis in vitro. And pro-apoptotic PTEN had been shown being targeted and downregulated. Therefore, our finding emphasized the oncogenic role of miR-21 in TNBC.
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Increase in nontuberculous mycobacteria isolated in shanghai, china: results from a population-based study.
PLoS ONE
PUBLISHED: 01-01-2014
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In China, the prevalence of nontuberculous mycobacteria (NTM) in isolates from mycobacterial culture-positive patients with pulmonary tuberculosis (TB) is largely unknown.
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Discovery and comparative profiling of microRNAs in representative monopodial bamboo (Phyllostachys edulis) and sympodial bamboo (Dendrocalamus latiflorus).
PLoS ONE
PUBLISHED: 01-01-2014
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According to the growth pattern of bamboo, sympodial bamboo and monopodial bamboo are considered as two mainly kinds of bamboo. They have different phenotypes and different characteristics in developmental stage. Much attention had been paid on the study of bamboo cultivation, processing, physiology, biochemistry and molecular biology, which had made great progresses in the last decade, especially for the highlighted achievement of the bamboo genomics. However, there is no information available on concerning comparative profiling of miRNAs between sympodial bamboo and monopodial bamboo, which might play important roles in the regulation of bamboo development.
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Fine physical and genetic mapping of powdery mildew resistance gene MlIW172 originating from wild emmer (Triticum dicoccoides).
PLoS ONE
PUBLISHED: 01-01-2014
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Powdery mildew, caused by Blumeria graminis f. sp. tritici, is one of the most important wheat diseases in the world. In this study, a single dominant powdery mildew resistance gene MlIW172 was identified in the IW172 wild emmer accession and mapped to the distal region of chromosome arm 7AL (bin7AL-16-0.86-0.90) via molecular marker analysis. MlIW172 was closely linked with the RFLP probe Xpsr680-derived STS marker Xmag2185 and the EST markers BE405531 and BE637476. This suggested that MlIW172 might be allelic to the Pm1 locus or a new locus closely linked to Pm1. By screening genomic BAC library of durum wheat cv. Langdon and 7AL-specific BAC library of hexaploid wheat cv. Chinese Spring, and after analyzing genome scaffolds of Triticum urartu containing the marker sequences, additional markers were developed to construct a fine genetic linkage map on the MlIW172 locus region and to delineate the resistance gene within a 0.48 cM interval. Comparative genetics analyses using ESTs and RFLP probe sequences flanking the MlIW172 region against other grass species revealed a general co-linearity in this region with the orthologous genomic regions of rice chromosome 6, Brachypodium chromosome 1, and sorghum chromosome 10. However, orthologous resistance gene-like RGA sequences were only present in wheat and Brachypodium. The BAC contigs and sequence scaffolds that we have developed provide a framework for the physical mapping and map-based cloning of MlIW172.
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Preclinical studies of N?-O-toluyl-fluorouracil-loaded lipid-based nanosuspensions in H??-bearing mice.
Int J Nanomedicine
PUBLISHED: 01-01-2014
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N3-O-toluyl-fluorouracil (TFU) is a potential antitumor prodrug of 5-fluorouracil (5-FU), but its poor solubility has limited its use in clinic. This study aimed to improve the bioavailability of TFU by preparing TFU-loaded lipid-based nanosuspensions (TFU-LNS) and perform a preclinical evaluation.
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Branch-like Hierarchical Heterostructure (?-Fe2O3/TiO2): A Novel Sensing Material for Trimethylamine Gas Sensor.
ACS Appl Mater Interfaces
PUBLISHED: 11-27-2013
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A novel hierarchical heterostructure of ?-Fe2O3 nanorods/TiO2 nanofibers with branch-like nanostructures was fabricated using a simple two-step process called the electrospinning technique and hydrothermal process. A high density of ?-Fe2O3 nanorods (about 200 nm in diameter) was uniformly deposited on a TiO2 nanofibers backbone. The phase purity, morphology, and structure of hierarchical heterostructures are investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and energy-dispersive X-ray (EDX) analysis. The highly branched ?-Fe2O3/TiO2 heterostructures provided an extremely porous matrix and high specific surface area required for high-performance gas sensors. Different nanostructured ?-Fe2O3/TiO2 heterostructures are also investigated by controlling the volume ratio of the reactants. The ?-Fe2O3/TiO2 heterostructures with a proper mixture ratio of the reactants sensor exhibit obviously enhanced sensing characteristics, including higher sensing response, lower operating temperature, faster response speed, and better selectivity in comparison with other ones. Moreover, the ?-Fe2O3/TiO2 heterostructures sensor also exhibits excellent sensing performances compared with ?-Fe2O3 nanorods and TiO2 nanofibers sensors. Thus, the combination of TiO2 nanofibers backbone and ?-Fe2O3 nanorods uniformly decorated endows a fascinating sensing performance as a novel sensing material with high response and rapid responding and recovering speed.
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Translucent Radiosity: Efficiently Combining Diffuse Inter-reflection and Subsurface Scattering.
IEEE Trans Vis Comput Graph
PUBLISHED: 11-13-2013
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It is hard to efficiently model the light transport in scenes with translucent objects for interactive applications. The interreflection between objects and their environments and the subsurface scattering through the materials intertwine to produce visual effects like color bleeding, light glows, and soft shading. Monte-Carlo based approaches have demonstrated impressive results but are computationally expensive, and faster approaches model either only inter-reflection or only subsurface scattering. In this paper, we present a simple analytic model that combines diffuse inter-reflection and isotropic subsurface scattering. Our approach extends the classical work in radiosity by including a subsurface scattering matrix that operates in conjunction with the traditional form factor matrix. This subsurface scattering matrix can be constructed using analytic, measurement-based or simulation-based models and can capture both homogeneous and heterogeneous translucencies. Using a fast iterative solution to radiosity, we demonstrate scene relighting and dynamically varying object translucencies at near interactive rates.
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Occurrence and removal efficiency of six polycyclic aromatic hydrocarbons in different wastewater treatment plants.
Water Sci. Technol.
PUBLISHED: 11-05-2013
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Occurrence and removal efficiency of six polycyclic aromatic hydrocarbons (PAHs) (fluoranthene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene) in wastewater were monitored at different treatment processes in three wastewater treatment plants (WWTPs) by using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Chromatographic separation was performed on a Waters Acquity UPLC BEHC18 column (1.7 ?m, 2.1 mm × 50 mm). A 0.2 ?m precolumn filter was used to protect the analytical column. The result indicated that (1) the total concentrations of six PAHs were 427, 318, and 220 ng L(-1) in the influent of three wastewater treatment plants, respectively. Among six PAHs, the content of fluoranthene was the highest, accounting for 62-66% of total PAHs. (2) Throughout the wastewater treatment process, different treatment units exhibited different removal efficiencies for six PAHs. Biological treatment stage and aerated grit chamber appeared to be necessary for effective removal of six PAHs. The removal efficiencies of six PAHs were 73-83% at biological treatment units, and 24-56% at the aerated grit stage, respectively. The final sedimentation and disinfection for PAH removal was minor.
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Investigation of cell free BIRC5 mRNA as a serum diagnostic and prognostic biomarker for colorectal cancer.
J Surg Oncol
PUBLISHED: 10-24-2013
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BIRC5 (Survivin), a key member of inhibitor of apoptosis family, has been shown in colorectal cancer (CRC) tumorigenesis and progress. This study investigated the expression levels of cell free BIRC5 mRNA in serum of CRC and assess its diagnostic and prognostic potential.
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Orthorhombic KSc2F7:Yb/Er nanorods: controlled synthesis and strong red upconversion emission.
Nanoscale
PUBLISHED: 10-17-2013
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For the first time, we have synthesized orthorhombic phase KSc2F7:20%Yb/2%Er (KSc2F7:Yb/Er) nanorods and further studied the crystal structure and morphology evolution, as well as their upconversion (UC) properties under varying F(-) contents and reaction temperatures. Different from ?-NaYF4:20%Yb/2%Er (NaYF4:Yb/Er) nanorods that usually give strong green UC luminescence, strong red UC emission was observed in KSc2F7:Yb/Er nanorods under 980 nm laser excitation. Their UC mechanisms are further analyzed and compared. This study provides a novel type of rare earth nanorods with strong red UC emissions which have great potential in high resolution 3-dimensional bioimaging, color displays, solid-state lasers, and photocatalysis.
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Different expression patterns of growth factors in rat fetuses with spina bifida aperta after in utero mesenchymal stromal cell transplantation.
Cytotherapy
PUBLISHED: 10-07-2013
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In a previous study, we successfully devised a prenatal surgical approach and transplanted mesenchymal stromal cells (MSCs) to fetal rat spinal column to treat retinoic acid-induced neural tube defects in rat. Our results show that MSCs survived, migrated and differentiated into neural lineage cells. We intended to study various growth factor expressions in rat fetal spinal cords with spina bifida aperta after in utero MSC transplantation and the effect of in vivo growth factor introduction for prenatal spina bifida treatment.
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Gene-gene interaction network analysis of ovarian cancer using TCGA data.
J Ovarian Res
PUBLISHED: 09-27-2013
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The Cancer Genome Atlas (TCGA) Data portal provides a platform for researchers to search, download, and analysis data generated by TCGA. The objective of this study was to explore the molecular mechanism of ovarian cancer pathogenesis.
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Sevoflurane preconditioning attenuates myocardial ischemia/reperfusion injury via caveolin-3-dependent cyclooxygenase-2 inhibition.
Circulation
PUBLISHED: 09-14-2013
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The inhaled anesthetic sevoflurane has been demonstrated to protect against myocardial ischemia/reperfusion (MI/R) injury via mechanisms involving AMP-activated protein kinase (AMPK) and caveolin-3 (Cav-3). However, the relative contributions of AMPK and Cav-3 to sevoflurane preconditioning (SF-PreCon)-mediated cardioprotection and their precise underlying mechanisms of action remain incompletely understood.
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Ferric chloride-Graphite Intercalation Compounds as Anode Materials for Li-ion Batteries.
ChemSusChem
PUBLISHED: 08-16-2013
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Ferric chloride-graphite intercalation compounds (FeCl3 -GICs) with stage?1 and stage?2 structures were synthesized by reacting FeCl3 and expanded graphite (EG) in air in a stainless-steel autoclave. As rechargeable Li-ion batteries, these FeCl3 -GICs exhibit high capacity, excellent cycling stability, and superior rate capability, which could be attributed to their unique intercalation features. This work may enable new possibilities for the fabrication of Li-ion batteries.
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Investigation of volatile organic metabolites in lung cancer pleural effusions by solid-phase microextraction and gas chromatography/mass spectrometry.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 08-15-2013
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Headspace solid-phase microextraction (HS-SPME) combined with gas chromatography/mass spectrometry (GC/MS) method was applied for the investigation of low molecular weight volatile organic metabolites (VOMs) in pleural effusion samples. Three important HS-SPME experimental parameters that influence extraction efficiency (fiber coating, extraction time and temperature of sampling) were optimized by a univariate optimization design. The highest extraction efficiency was obtained when sampling was performed at 50°C for 10min under agitation using a carboxen/polydimethylsiloxane (CAR/PDMS) fiber. A total of 36 volatile metabolites belonging to nine distinct chemical classes were identified in 40 pleural effusion samples (20 malignant effusions from lung cancer patients and 20 benign effusions from inflammatory patients). Ketones, alcohols, and benzene derivatives were the main chemical classes for the metabolomic profile of malignant effusions. The average peak areas of ketones and alcohols were much higher in malignant group compared to benign group. Together with phenols, they exhibit significant differences (P<0.05) between the two groups. Particularly, the average peak areas of cyclohexanone and 2-ethyl-1-hexanol in malignant effusions were significantly higher than those in benign ones. Furthermore, of the 36 identified metabolites, 5 compounds including cyclohexanone and 2-ethyl-1-hexanol were found to be statistically different (Students t-test, P<0.05) between the two groups by statistical analysis based on the peak areas of all identified metabolites. Among them, cyclohexanone and 2-ethyl-1-hexanol might be considered as candidate biomarkers of lung cancer to differentiate malignant from benign effusions. The results show that HS-SPME-GC/MS is a simple, rapid, sensitive and solvent-free method for the determination of VOMs in pleural effusion samples. Pleural effusion is a valuable sample source for observation of changes in VOMs for differentiation between lung cancer patients and inflammatory individuals.
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Characterization of six missense mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) gene in Chinese children with hypophosphatasia.
Cell. Physiol. Biochem.
PUBLISHED: 08-12-2013
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Hypophosphatasia, a rare inherited disease characterized by defective mineralization of bone and teeth, is caused by various mutations in the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP) gene. Our aim was to determine the mutations on TNSALP gene in three Chinese children diagnosed as having hypophosphatasia.
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Association between Cyclin D1 polymorphism and oral cancer susceptibility: a meta-analysis.
Tumour Biol.
PUBLISHED: 07-24-2013
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Data from several case-control studies on the relation between the Cyclin D1 (CCND1) G870A polymorphism and oral cancer susceptibility implicated conflicting conclusions. Thus, a meta-analysis was performed to derive a more precise evaluation of the association. We searched PubMed and Embase for related studies that had been published in English and eight available studies were finally included in the meta-analysis. Odd ratios (ORs) and 95 % confidence intervals (CIs) were calculated for each study. Our meta-analysis suggested that CCND1 G870A polymorphism was not associated with oral cancer risk (OR AA vs. GG?=?1.08, 95 % CI?=?0.90-1.30, P heterogeneity?=?0.175; OR AA + GA vs. GG?=?1.02, 95 % CI?=?0.91-1.14, P heterogeneity?=?0.781; OR AA vs. GA + GG?=?1.16, 95 % CI?=?0.98-1.36, P heterogeneity?=?0.107; OR A vs. G?=?1.05 95 % CI?=?0.96-1.15, P heterogeneity?=?0.211; OR GA vs. GG?=?0.94, 95 % CI?=?0.82-1.08, P heterogeneity?=?0.935). However, in the subgroup analysis by ethnicity, possible significance among Asian groups was indicated in two genetic models (OR AA vs. GA + GG?=?1.27, 95 % CI?=?1.05-1.54, P heterogeneity?=?0.572; OR allele A vs. allele G?=?1.11, 95 % CI?=?1.00-1.24, P heterogeneity?=?0.211). Taken together, the meta-analysis revealed that CCND1 G870A polymorphism might be correlated with the susceptibility of oral cancer in Asians.
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AML1/ETO triggers epigenetic activation of EGR1 inducing apoptosis in t(8;21) acute myeloid leukemia.
FEBS J.
PUBLISHED: 07-15-2013
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t(8;21)(q22;q22) is the most common chromosomal translocation in acute myeloid leukemia (AML), and it gives rise to AML1/ETO (+) type AML,which has a relatively favorable prognosis. However, the molecular mechanism related to a favorable prognosis in AML1/ETO (+) AML is still not fully understood. Our results show that the AML1/ETO fusion protein triggered the activation of the early growth responsive gene l (EGR1) by binding at AML1-binding sites on the EGR1 promoter and, subsequently, recruited acetyltransferase P300, which is known to acetylate histones. However, the AML1/ETO fusion protein could not recruit DNMTs and HDACs; therefore, EGR1 expression was affected by histone acetylation but not by DNA methylation. Both transcription and translation of EGR1 were higher in AML1/ETO (+) AML cell lines than in AML1/ETO (-) AML cell lines, due to acetylation. Further, when AML1/ETO (+) AML cell lines were treated with C646 (P300 inhibitor) and TSA (HDAC inhibitor), EGR1 expression significantly decreased and increased, respectively. In addition, treatment with 5-Aza (methyltransferase inhibitor) did not cause any significant change in EGR1 expression. Overexpression of EGR1 inhibited cell proliferation and promoted apoptosis, and EGR1 knockout promoted cell proliferation. Thus, EGR1 could be a novel prognostic factor for favorable outcome in AML1/ETO (+) AML. The results of our study may explain the molecular mechanisms underlying the favorable prognosis in AML1/ETO (+) AML. This article is protected by copyright. All rights reserved.
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The role of NEFL in cell growth and invasion in head and neck squamous cell carcinoma cell lines.
J. Oral Pathol. Med.
PUBLISHED: 07-09-2013
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The neurofilament light polypeptide (NEFL) gene located on chromosome 8q21 is associated with the cancer of several organs and is regarded as a potential tumor suppressor gene. However, the role of the NEFL protein has not yet been studied in cancer cells. Although evidence suggests that there is a correlation between NEFL expression and cancer, studies regarding the role of the NEFL protein have been mostly limited to neurological diseases, such as Charcot-Marie-Tooths disease (CMT). Most of these studies have not explored the role of NEFL in cancer cell apoptosis and/or invasion. In this study, NEFL expression was manipulated, and apoptosis and invasion were compared in head and neck squamous cell carcinoma cell lines. The results show that the expression of NEFL induces cancer cell apoptosis and inhibits invasion in these cell lines, suggesting that NEFL may play a role in cancer cell apoptosis and invasion.
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Transmissible gastroenteritis virus infection induces cell cycle arrest at S and G2/M phases via p53-dependent pathway.
Virus Res.
PUBLISHED: 06-23-2013
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p53 signaling pathway plays an important role in the regulation of cell cycle. Our previous studies have demonstrated that TGEV infection induces the activation of p53 signaling pathway. In this study we investigated the effects of TGEV infection on the cell cycle of host cells and the roles of p53 activation in this process. The results showed that TGEV infection induced cell cycle arrest at S and G2/M phases in both asynchronous and synchronized PK-15 and ST cells, while UV-inactivated TGEV lost the ability of induction of cell cycle arrest. TGEV infection promoted p21 accumulation, down-regulated cell cycle-regulatory proteins cyclins B1, cdc2, cdk2 and PCNA. Further studies showed that inhibition of p53 signaling could attenuate the TGEV-induced S- and G2/M-phase arrest by reversing the expression of p21 and corresponding cyclin/cdk. In addition, TGEV infection of the cells synchronized in various stages of cell cycle showed that viral genomic RNA and subgenomic RNA, and virus titer were higher in the cells released from S-phase- or G2/M phase-synchronized cells than that in the cells released from the G0/G1 phase-synchronized or asynchronous cells after 18h p.i. Taken together, our data suggested that TGEV infection induced S and G2/M phase arrest in host cells, which might provide a favorable condition for viral replication.
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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.