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Find video protocols related to scientific articles indexed in Pubmed.
Actively controlled super-resolution using graphene-based structure.
Opt Express
PUBLISHED: 11-18-2014
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A super-resolution (with ?/50 resolution ability at mid-infrared region) device that consists of a monolayer graphene sandwiched between two dielectric materials with two alternate chemical potentials in graphene (which can be obtained by alternately applying two biased voltages to graphene) is proposed and analyzed. When the subwavelength resolution is achieved, the graphene-based device can be viewed as an effective optical medium with alternate arrangement of positive and negative refractive indices. And the isofrequency dispersion curves of the effective optical medium have the hyperbolic form. Furthermore, the super-resolution at different desired frequencies can be reached by merely changing the chemical potentials of graphene. The proposed devices have potential applications in multi-functional material, real-time subwavelength imaging, and high-density optoelectronic components for using the abnormal diffraction feature.
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CMPD: cancer mutant proteome database.
Nucleic Acids Res.
PUBLISHED: 11-16-2014
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Whole-exome sequencing, which centres on the protein coding regions of disease/cancer associated genes, represents the most cost-effective method to-date for deciphering the association between genetic alterations and diseases. Large-scale whole exome/genome sequencing projects have been launched by various institutions, such as NCI, Broad Institute and TCGA, to provide a comprehensive catalogue of coding variants in diverse tissue samples and cell lines. Further functional and clinical interrogation of these sequence variations must rely on extensive cross-platforms integration of sequencing information and a proteome database that explicitly and comprehensively archives the corresponding mutated peptide sequences. While such data resource is a critical for the mass spectrometry-based proteomic analysis of exomic variants, no database is currently available for the collection of mutant protein sequences that correspond to recent large-scale genomic data. To address this issue and serve as bridge to integrate genomic and proteomics datasets, CMPD (http://cgbc.cgu.edu.tw/cmpd) collected over 2 millions genetic alterations, which not only facilitates the confirmation and examination of potential cancer biomarkers but also provides an invaluable resource for translational medicine research and opportunities to identify mutated proteins encoded by mutated genes.
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Highly Efficient Visible Light Photocatalytic Reduction of CO2 to Hydrocarbon Fuels by Cu-Nanoparticle Decorated Graphene Oxide.
Nano Lett.
PUBLISHED: 11-03-2014
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The production of renewable solar fuel through CO2 photoreduction, namely artificial photosynthesis, has gained tremendous attention in recent times due to the limited availability of fossil-fuel resources and global climate change caused by rising anthropogenic CO2 in the atmosphere. In this study, graphene oxide (GO) decorated with copper nanoparticles (Cu-NPs), hereafter referred to as Cu/GO, has been used to enhance photocatalytic CO2 reduction under visible-light. A rapid one-pot microwave process was used to prepare the Cu/GO hybrids with various Cu contents. The attributes of metallic copper nanoparticles (?4-5 nm in size) in the GO hybrid are shown to significantly enhance the photocatalytic activity of GO, primarily through the suppression of electron-hole pair recombination, further reduction of GO's bandgap, and modification of its work function. X-ray photoemission spectroscopy studies indicate a charge transfer from GO to Cu. A strong interaction is observed between the metal content of the Cu/GO hybrids and the rates of formation and selectivity of the products. A factor of greater than 60 times enhancement in CO2 to fuel catalytic efficiency has been demonstrated using Cu/GO-2 (10 wt % Cu) compared with that using pristine GO.
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A Preliminary Examination of Aerobic Exercise Effects on Resting EEG in Children With ADHD.
J Atten Disord
PUBLISHED: 11-01-2014
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This study attempted to determine whether the effects of physical exercise were reflected in the resting electroencephalographic (EEG) pattern of ADHD children.
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Structure and Ligand-Based Design of mTOR and PI3-Kinase Inhibitors Leading to the Clinical Candidates VS-5584 (SB2343) and SB2602.
J Chem Inf Model
PUBLISHED: 10-23-2014
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Phosphoinositide 3-kinases (PI3Ks) and the mammalian target of rapamycin (mTOR) act as critical effectors in a commonly deregulated cell signaling pathway in human cancers. The abnormal activation of the PI3K/mTOR pathway has been shown to play a role in initiation, progression, and metastasis of human tumors. Being one of the most frequently activated pathways in cancer, much effort has been directed toward inhibition of the PI3K/mTOR pathway as a novel oncology therapy. Previous work by a number of groups has revealed several selective PI3K and dual mTOR/PI3K inhibitors. However, there are few reports of therapeutic agents with a pan-PI3K/mTOR inhibitory profile within a narrow concentration range. We therefore initiated a drug discovery project with the aim of discovering dual mTOR/PI3K inhibitors which would equipotently inhibit the 4 isoforms of PI3K, ?, ?, ?, and ?, and mTOR a compelling profile for powerful blockage of the PI3K/mTOR pathway. A pharmacophore model was generated and used for designing a series of novel compounds, based on a purine scaffold, which potently inhibited mTOR and PI3Ks. These compounds contained a phenol headgroup essential for binding to the target proteins. Early efforts concentrated on finding replacements for the phenol as it was rapidly conjugated resulting in a short half-life in vivo. Compounds with a variety of headgroups were docked into the PI3K? and mTOR ATP-binding sites, and aminopyrimidine and aminopyrazine were found to make excellent phenol replacements. Further structure guided optimization of side chains in the 8- and 9-positions of the purine resulted in potent inhibitors with good PKDM properties. As the PI3 kinases play a role in insulin signaling, it is believed that targeting mTOR selectively may give the benefit of blocking the AKT-pathway while avoiding the potential side effects associated with PI3K inhibition. As a result we designed a further series of selective mTOR kinase inhibitors. The project was successfully concluded by progressing both a dual mTOR/PI3K inhibitor, SB2343, and a selective mTOR inhibitor, SB2602, into preclinical development. SB2343 has since entered phase 1 clinical development as VS-5584.
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Observation of valley-dependent beams in photonic graphene.
Opt Express
PUBLISHED: 10-17-2014
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Valley-dependent propagation of light in an artificial photonic hexagonal lattice, akin to electrons in graphene, is investigated in microwave regime. Both numerical and experimental results show that the valley degeneracy in the photonic graphene is broken when the frequency is away from the Dirac point. The peculiar anisotropic wave transport property due to distinct valleys is analyzed using the equifrequency contours. More interestingly, the valley-dependent self-collimation and beam splitting phenomena are experimentally demonstrated with the armchair and zigzag interfaces, respectively. Our results confirm that there are two inequivalent Dirac points that lead to two distinct valleys in photonic graphene, which could be used to control the flow of light and might be used to carry information in valley polarized beam splitter, collimator or guiding device.
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Silencing of miRNA-148a by hypermethylation activates the integrin-mediated signaling pathway in nasopharyngeal carcinoma.
Oncotarget
PUBLISHED: 10-04-2014
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MicroRNAs (miRNAs) play a pivotal role in carcinogenesis by suppressing oncogenes or tumor suppressor genes. Various studies have identified numerous miRNAs and their diverse targets; however, the consequences of dysregulated miRNAs in nasopharyngeal carcinoma (NPC) remain unclear. For this study, we found that miR-148a is downregulated through hypermethylation in NPC biopsies and NPC cell lines compared with adjacent normal and NP cells respectively. Promoter assays demonstrated that upstream stimulatory factor 1 (USF1) is a crucial transcription factor that activates miR-148a promoter activity. EMSA assays confirmed that purified USF1 binds better toward the unmethylated than the methylated CG-containing USF1 consensus probe. The ectopic expression of miR-148a inhibits cell migration in NPC cells through the suppression of integrin-mediated signaling by targeting VAV2, WASL and ROCK1. Biochemical and functional assays provided supporting evidence that these 3 genes are the downstream targets of miR-148a in NPC cells. Furthermore, immunohistochemical staining and Western blotting analysis revealed that the 3 oncogenic targets of miR-148a were overexpressed in NPC biopsies, suggesting that the inactivation of miR-148a caused by DNA methylation promotes NPC progression. Overall, our findings revealed that miR-148a can act as tumor suppressor miRNA and serve as a biomarker as well as a therapeutic target for NPC.
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Successful aging defined by health-related quality of life and its determinants in community-dwelling elders.
BMC Public Health
PUBLISHED: 09-18-2014
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Successful aging in old age is important. However, the determinants of successful aging vary across populations due to cultural differences, and only a limited number of studies have addressed these determinants in Taiwan population. This study aimed to evaluate successful aging via better physical and mental functions as well as to explore associated determinants in an elderly Taiwan population that had no impaired cognitive function.
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Full-depth epidermis tomography using a Mirau-based full-field optical coherence tomography.
Biomed Opt Express
PUBLISHED: 09-01-2014
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With a Gaussian-like broadband light source from high brightness Ce(3+):YAG single-clad crystal fiber, a full-field optical coherence tomography using a home-designed Mirau objective realized high quality images of in vivo and excised skin tissues. With a 40 × silicone-oil-immersion Mirau objective, the achieved spatial resolutions in axial and lateral directions were 0.9 and 0.51 ?m, respectively. Such a high spatial resolution enables the separation of lamellar structure of the full epidermis in both the cross-sectional and en face planes. The number of layers of stratum corneum and its thickness were quantitatively measured. This label free and non-invasive optical probe could be useful for evaluating the water barrier of skin tissue in clinics. As a preliminary in vivo experiment, the blood vessel in dermis was also observed, and the flowing of the red blood cells and location of the melanocyte were traced.
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Evaluation of microvasculature at the auditory midbrain -the benefits of sectioning at a tangential angle.
Microsc. Res. Tech.
PUBLISHED: 08-24-2014
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Vascular remodeling in the brain occurs as a plastic change following neural over-activity. The auditory midbrain (or inferior colliculus, IC) is an ideal place to study sound-induced vascular changes because it is the brain's most vascularized structure and it is tonotopically organized. However, its micro-vascular pattern remains poorly understood. Since the IC is a sphere-like structure, the histological assessment of vasculature could depend on the angle of sectioning. Here, we studied the effects of cutting the IC at different angles on microvascular assessment, specifically: micro-vascular density and the shape of microvascular lumen. Photomicrographs were taken from 5 µm toluidine blue-stained histological sections obtained at two angles of sectioning: (a) the conventional coronal sectioning, and (b) a novel "tangential" sectioning (tangential to the dorso-medial surface of the IC). Results showed that the tangential sections, in comparison with the coronal sections, yielded (a) a higher count of micro-vascular density and (b) a higher proportion of round-shaped micro-vascular lumens. This discrepancy in results between two cut angles is likely related to the spatial pattern of blood vessels supplying the IC. We propose that the tangential sectioning should be adopted as standard for the accurate study of microvasculature in the IC. Microsc. Res. Tech., 2014. © 2014 Wiley Periodicals, Inc.
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Monolayer MoSe2 grown by chemical vapor deposition for fast photodetection.
ACS Nano
PUBLISHED: 08-07-2014
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Monolayer molybdenum disulfide (MoS2) has become a promising building block in optoelectronics for its high photosensitivity. However, sulfur vacancies and other defects significantly affect the electrical and optoelectronic properties of monolayer MoS2 devices. Here, highly crystalline molybdenum diselenide (MoSe2) monolayers have been successfully synthesized by the chemical vapor deposition (CVD) method. Low-temperature photoluminescence comparison for MoS2 and MoSe2 monolayers reveals that the MoSe2 monolayer shows a much weaker bound exciton peak; hence, the phototransistor based on MoSe2 presents a much faster response time (<25 ms) than the corresponding 30 s for the CVD MoS2 monolayer at room temperature in ambient conditions. The images obtained from transmission electron microscopy indicate that the MoSe exhibits fewer defects than MoS2. This work provides the fundamental understanding for the differences in optoelectronic behaviors between MoSe2 and MoS2 and is useful for guiding future designs in 2D material-based optoelectronic devices.
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Monolayer MoS2 heterojunction solar cells.
ACS Nano
PUBLISHED: 07-22-2014
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We realized photovoltaic operation in large-scale MoS2 monolayers by the formation of a type-II heterojunction with p-Si. The MoS2 monolayer introduces a built-in electric field near the interface between MoS2 and p-Si to help photogenerated carrier separation. Such a heterojunction photovoltaic device achieves a power conversion efficiency of 5.23%, which is the highest efficiency among all monolayer transition-metal dichalcogenide-based solar cells. The demonstrated results of monolayer MoS2/Si-based solar cells hold the promise for integration of 2D materials with commercially available Si-based electronics in highly efficient devices.
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Functionalized magnetic iron oxide (Fe3O4) nanoparticles for capturing gram-positive and gram-negative bacteria.
J Biomed Nanotechnol
PUBLISHED: 07-15-2014
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The development of nanotechnology in biology and medicine has raised the need for conjugation of nanoparticles (NPs) to biomolecules. In this study, magnetic and functionalized magnetic iron oxide nanoparticles were synthesized and used as affinity probes to capture Gram-positive/negative bacteria. The morphology and properties of the magnetic NPs were examined by transmission electron microscopy, Fourier transform infrared spectroscopy, and zeta potential measurements. Furthermore, this study investigated the interaction between functionalized magnetic nanoparticles and Gram positive/negative bacteria. The positively and negatively charged magnetic nanoparticles include functionalities of Fe3O4, SiO2, TiO2, ZrO2, poly ethyleneimine (PEI) and poly acrylic acid. Their capture efficiencies for bacteria were investigated based on factors such as zeta potential, concentration and pH value. PEI particles carry a positive charge over a range of pH values from 3 to 10, and the particles were found to be an excellent candidate for capturing bacteria over such pH range. Since the binding force is mainly electrostatic, the architecture and orientation of the functional groups on the NP surface are not critical. Finally the captured bacteria were analyzed using matrix-assisted laser desorption/ionization mass spectrometry. The minimum detection limit was 10(4) CFU/mL and the analysis time was reduced to be less than 1 hour. In addition, the detection limit could be reduced to an extremely low concentration of 50 CFU/mL when captured bacteria were cultivated.
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Tunable narrow-bandpass filter based on an asymmetric photonic bandgap structure with a dual-mode liquid crystal.
Opt Express
PUBLISHED: 07-01-2014
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A one-dimensional asymmetric photonic crystal with dual-frequency liquid crystal as a central defect layer was demonstrated. Such asymmetric structure was characterized by the dramatic increase in intensity of the electric field of light localized at the overlapped photonic bandgap edges, thereby enhancing the observed transmittance of the spectral windows originating from the defect layer. The defect layer was made of a dual-mode liquid crystal that exhibited not only electrical tunability and switchability but also optical bistability. Consequently, tunable and bistable defect modes can be realized in the photonic structure. This asymmetric photonic crystal structure is promising and should be further explored for photonic device applications.
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Scribble1/AP2 Complex Coordinates NMDA Receptor Endocytic Recycling.
Cell Rep
PUBLISHED: 06-18-2014
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The appropriate trafficking of glutamate receptors to synapses is crucial for basic synaptic function and synaptic plasticity. It is now accepted that NMDA receptors (NMDARs) internalize and are recycled at the plasma membrane but also exchange between synaptic and extrasynaptic pools; these NMDAR properties are also key to governing synaptic plasticity. Scribble1 is a large PDZ protein required for synaptogenesis and synaptic plasticity. Herein, we show that the level of Scribble1 is regulated in an activity-dependent manner and that Scribble1 controls the number of NMDARs at the plasma membrane. Notably, Scribble1 prevents GluN2A subunits from undergoing lysosomal trafficking and degradation by increasing their recycling to the plasma membrane following NMDAR activation. Finally, we show that a specific YxxR motif on Scribble1 controls these mechanisms through a direct interaction with AP2. Altogether, our findings define a molecular mechanism to control the levels of synaptic NMDARs via Scribble1 complex signaling.
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Cognitive and epilepsy outcomes after epilepsy surgery caused by focal cortical dysplasia in children: early intervention maybe better.
Childs Nerv Syst
PUBLISHED: 06-04-2014
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Focal cortical dysplasia (FCD) is a specific malformation of cortical development harboring intrinsic epileptogenicity, and most of the patients develop drug-resistant epilepsy in early childhood. The detrimental effects of early and frequent seizures on cognitive function in children are significant clinical issues. In this study, we evaluate the effects of early surgical intervention of FCD on epilepsy outcome and cognitive development.
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Dose-response Relationship between Exercise Duration and Cognition.
Med Sci Sports Exerc
PUBLISHED: 05-30-2014
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The study aimed to provide evidence-based recommendations for the prescription of a single session of exercise to improve cognitive performance. In particular, the purpose was to determine the dose-response relationship between exercise duration and cognitive performance for a moderate intensity session of aerobic exercise.
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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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Salivary auto-antibodies as noninvasive diagnostic markers of oral cavity squamous cell carcinoma.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 05-23-2014
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Oral cavity squamous cell carcinoma (OSCC) is one of the most common cancers worldwide, and its incidence is still increasing. Approximately 50% of patients with OSCC die within 5 years after diagnosis, mostly ascribed to the fact that the majority of patients present advanced stages of OSCC at the time of diagnosis.
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Effects of Physical Activity Intervention on Motor Proficiency and Physical Fitness in Children With ADHD: An Exploratory Study.
J Atten Disord
PUBLISHED: 05-16-2014
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This study explored how a 12-week simulated developmental horse-riding program (SDHRP) combined with fitness training influenced the motor proficiency and physical fitness of children with ADHD.
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Insertion sequence transposition determines imipenem resistance in Acinetobacter baumannii.
Microb. Drug Resist.
PUBLISHED: 05-15-2014
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This study employed genomewide analysis to investigate potential resistance mechanisms in Acinetobacter baumannii following imipenem exposure. Imipenem-selected mutants were generated from the imipenem-susceptible strain ATCC 17978 by multistep selection resistance. Antibiotic susceptibilities were examined, and the selected mutants originated from the ATCC 17978 strain were confirmed by pulsed-field gel electrophoresis. The genomic sequence of a resistant mutant was analyzed using a next-generation sequencing platform, and genetic recombination was further confirmed by PCR. The result showed that phenotypic resistance was observed with carbapenem upon exposure to various concentrations of imipenem. Genomewide analysis showed that ISAba1 transposition was initiated by imipenem exposure at concentrations up to 0.5?mg/L. Transposition of ISAba1 upstream of blaOXA-95 was detected in all the selected mutants. The expression of blaOXA-95 was further analyzed by quantitative PCR, and the results demonstrated that a 200-fold increase in gene expression was required for resistance to imipenem. This study concluded that imipenem exposure at a concentration of 0.5?mg/L mediated the transposition of ISAba1 upstream of the blaOXA-95 gene and resulted in the overexpression of blaOXA-95 gene, which may play a major role in the resistance to imipenem in A. baumannii.
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Transcriptome profiling in imipenem-selected Acinetobacter baumannii.
BMC Genomics
PUBLISHED: 05-11-2014
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Carbapenem-resistance in Acinetobacter baumannii has gradually become a global challenge. To identify the genes involved in carbapenem resistance in A. baumannii, the transcriptomic responses of the completely sequenced strain ATCC 17978 selected with 0.5 mg/L (IPM-2 m) and 2 mg/L (IPM-8 m) imipenem were investigated using RNA-sequencing to identify differences in the gene expression patterns.
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Matrix metalloproteinase 12 is induced by heterogeneous nuclear ribonucleoprotein K and promotes migration and invasion in nasopharyngeal carcinoma.
BMC Cancer
PUBLISHED: 05-06-2014
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Overexpression of heterogeneous nuclear ribonucleoprotein K (hnRNP K), a DNA/RNA binding protein, is associated with metastasis in nasopharyngeal carcinoma (NPC). However, the mechanisms underlying hnRNP K-mediated metastasis is unclear. The aim of the present study was to determine the role of matrix metalloproteinase (MMP) in hnRNP K-mediated metastasis in NPC.
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Effects of the mTOR inhibitor Rapamycin on Monocyte-Secreted Chemokines.
BMC Immunol.
PUBLISHED: 04-18-2014
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BackgroundMammalian target of rapamycin (mTOR) inhibitors, such as sirolimus and its derivative, everolimus, are potent immunosuppressive and antiproliferative drugs. Inflammatory diseases are characterized by immunological dysfunction, and monocyte recruitment underlies the mechanism of cell damage. Chemokines attract inflammatory cells to sites of inflammation. Interleukin-8 (IL-8/CXCL8); the monocyte chemoattractant protein-1 (MCP-1/CCL2); the regulated on activation, normal T cell expressed, presumably secreted protein (RANTES/CCL5); the macrophage inflammatory protein (MIP)-1¿ (CCL3); and MIP-1ß (CCL4) are involved in the pathogenesis of inflammation. However, whether mTOR inhibitors moderate the production of chemokines in monocytes remains unclear.MethodsA human monocyte cell line, THP-1, and primary monocytes obtained from human volunteers, were stimulated using lipopolysaccharide (LPS), and then treated with sirolimus. The expression of the MCP-1, RANTES, IL-8, MIP-1¿, MIP-1ß, and TNF-¿ proteins was measured using enzyme-linked immunosorbent assays, and intracellular signalling was examined using western blotting.ResultsSirolimus significantly suppressed the LPS-induced expression of MCP-1, IL-8, RANTES, MIP-1¿, and MIP-1ß in the THP-1 cells and human primary monocytes. The mitogen-activated protein kinase (MAPK) inhibitors that were examined suppressed the LPS-induced expression of MCP-1, IL-8, RANTES, MIP-1¿, and MIP-1ß. In addition, sirolimus suppressed the LPS-induced phosphorylation of p38 and p65 in the THP-1 and human primary monocytes.ConclusionSirolimus downregulates the expression of chemokines in monocytes, including MCP-1, RANTES, IL-8, MIP-1¿, and MIP-1ß, by inhibiting the NF-¿B-p65 and MAPK-p38 signalling pathways.
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Effect of acute exercise and cardiovascular fitness on cognitive function: An event-related cortical desynchronization study.
Psychophysiology
PUBLISHED: 04-17-2014
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This study aimed to clarify the effects of acute exercise and cardiovascular fitness on cognitive function using the Stroop test and event-related desynchronization (ERD) in an aged population. Old adults (63.10?±?2.89 years) were first assigned to either a high-fitness or a low-fitness group, and they were then subjected to an acute exercise treatment and a reading control treatment in a counterbalanced order. Alpha ERD was recorded during the Stroop test, which was administered after both treatments. Acute exercise improved cognitive performance regardless of the level of cognition, and old adults with higher fitness levels received greater benefits from acute exercise. Additionally, acute exercise, rather than overall fitness, elicited greater lower and upper alpha ERDs relative to the control condition. These findings indirectly suggest that the beneficial effects of acute exercise on cognitive performance may result from exercise-induced attentional control observed during frontal neural excitation.
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Plasmalemmal Vesicle Associated Protein (PLVAP) as a therapeutic target for treatment of hepatocellular carcinoma.
BMC Cancer
PUBLISHED: 04-16-2014
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Hepatocellular carcinoma (HCC) is a malignancy with poor survival outcome. New treatment options for the disease are needed. In this study, we identified and evaluated tumor vascular PLVAP as a therapeutic target for treatment of HCC.
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Secretome Profiling of Primary Cells Reveals That THBS2 Is a Salivary Biomarker of Oral Cavity Squamous Cell Carcinoma.
J. Proteome Res.
PUBLISHED: 04-16-2014
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Oral cavity squamous cell carcinoma (OSCC), which is a leading cause of cancer-related death worldwide, is frequently associated with poor prognosis and mortality. The discovery of body fluid-accessible biomarkers may help improve the detection of OSCC. In the present work, we established primary cell cultures derived from OSCC and adjacent noncancerous epithelium and performed comparative profiling of their secretomes. Using spectral counting-based label-free quantification, we found that 64 proteins were significantly higher in primary OSCC cells compared with primary adjacent noncancerous cells. We then retrieved the mRNA expression levels of these 64 proteins in oral cavity tumor and noncancerous tissues from public domain array-based transcriptome data sets and used this information to prioritize the biomarker candidates. We identified 19 candidates; among them, the protein levels of THBS2, UFD1L, and DNAJB11 were found to be elevated in OSCC tissues compared with adjacent noncancerous epithelia. Importantly, higher levels of THBS2 in OSCC tissues were associated with a higher overall pathological stage, positive perineural invasion, and a poorer prognosis. Moreover, the salivary levels of THBS2 in OSCC patients were elevated compared to those of noncancer controls. Our results collectively indicate that analysis of the primary cell secretome is a feasible strategy for biomarker identification, and that THBS2 is a potentially useful salivary marker for the detection of OSCC.
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Effects of an aquatic exercise program on inhibitory control in children with ADHD: a preliminary study.
Arch Clin Neuropsychol
PUBLISHED: 04-02-2014
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The purpose of this preliminary study was to examine whether an aquatic exercise intervention that involves both aerobic and coordinative exercises influences restraint inhibition in children with ADHD. Thirty participants were assigned to either an aquatic exercise or a wait-list control group. Participants were assessed by Go/Nogo Task and motor ability prior to and after an 8-week exercise intervention (twice per week, 90 min per session) or a control intervention. Significant improvements in accuracy associated with the Nogo stimulus and the coordination of motor skills were observed over time in the exercise group compared with the control group. Only main effects of group were found for reaction time and accuracy associated with the Go stimulus. These findings suggest that an exercise program that involves both quantitative and qualitative exercise characteristics facilitates the restraint inhibition component of behavioral inhibition in children with ADHD.
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Antrodia cinnamomea profoundly exalted the reversion of activated hepatic stellate cells by the alteration of cellular proteins.
Food Chem. Toxicol.
PUBLISHED: 03-24-2014
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The direct modulation of Antrodia cinnamomea (AC) on the prominent role of liver fibrosis-hepatic stellate cells (HSCs) in situ remains unclear. Firstly, the administration of A. cinnamomea mycelial extract (ACME) could improve liver morphology and histological changes including collagen formation and GPT activity in the liver of thioacetamide (TAA)-injured rats. The morphology and fatty acid restore of TAA-induced HSCs (THSCs) returned to the non-chemical induced HSCs (NHSCs) type as measured by immunofluorescence and Oil Red O staining. PPAR? was upregulated associated with the lowering of ?-SMA protein in NHSC-ACME. ACME inhibited the MMP-2 activity in NHSCs by gelatin Zymography. After LC-MS/MS, the cytoskeleton (tubulin, lamin A) and heat shock protein 8 in NHSC-ACME, and guanylate kinase, brain-specific kinase, SG-II and p55 proteins were downregulated in THSC-ACME. Whereas MHC class II, SMC6 protein, and phospholipase D were upregulated in NHSC-ACME. Furthermore, PKG-1 was downregulated in NHSC-ACME and upregulated in THSC-ACME. SG-II and p55 proteins were downregulated in NHSC-ACME and THSC-ACME by Western blotting. Taken together, the beneficial effect of A. cinnamomea on the induction of HSC cellular proteins is potentially applied as an alternative and complementary medicine for the prevention and amelioration of a liver injury.
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Strain-induced pseudomagnetic fields in twisted graphene nanoribbons.
Phys. Rev. Lett.
PUBLISHED: 03-06-2014
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We present, for the first time, an atomic-level and quantitative study of a strain-induced pseudomagnetic field in graphene nanoribbons with widths of hundreds of nanometers. We show that twisting strongly affects the band structures of graphene nanoribbons with arbitrary chirality and generates well-defined pseudo-Landau levels, which mimics the quantization of massive Dirac fermions in a magnetic field up to 160 T. Electrons are localized either at ribbon edges forming the edge current or at the ribbon center forming the snake orbit current, both being valley polarized. Our result paves the way for the design of new graphene-based nanoelectronics.
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Prevalence and mapping of a plasmid encoding a type IV secretion system in Acinetobacter baumannii.
Genomics
PUBLISHED: 03-04-2014
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We investigated the prevalence of a type IV secretion system (T4SS)-bearing plasmid among clinical isolates of carbapenem-resistant Acinetobacter baumannii (CRAB) using plasmid replicon typing. The complete sequence of a T4SS-bearing plasmid, pAB_CC, isolated from A. baumannii TYTH-1 was determined, and a comparative analysis of the T4SS gene modules was performed. Of the 129 isolates studied, GR6 (repAci6) was the most common (45 of 96 isolates) and was strongly linked with the T4SS. A comparative analysis of the T4SS locus in seven plasmid genomes, including pAB_CC, pACICU2, pABKp1, pABTJ1, p1BJAB0714, p2BJAB0868, and p2ABTCDC0715, indicated that fourteen genes on these plasmids were highly conserved compared to those of the F plasmid. Additionally, the chromosomes in the seven representative isolates may be evolutionarily distinct from their intrinsic T4SS-bearing plasmids, suggesting that the two T4SS lineages emerged long before the appearance of EC II. These two lineages are now widespread in A. baumannii strains.
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Overexpression of BST2 is associated with nodal metastasis and poorer prognosis in oral cavity cancer.
Laryngoscope
PUBLISHED: 03-02-2014
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Bone marrow stromal cell antigen 2 (BST2) was one of the proteins that were found to be related to tumor metastasis in our previous proteomic study. Now we examine its clinical role on the oral cavity squamous cell carcinoma (OSCC).
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Efficient production of mutant phytase (phyA-7) derived from Selenomonas ruminantium using recombinant Escherichia coli in pilot scale.
J. Biosci. Bioeng.
PUBLISHED: 02-21-2014
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A mutant gene of rumen phytase (phyA-7) was cloned into pET23b(+) vector and expressed in the Escherichia coli BL21 under the control of the T7 promoter. The study of fermentation conditions includes the temperature impacts of mutant phytase expression, the effect of carbon supplements over induction stage, the inferences of acetic acid accumulation upon enzyme expression and the comparison of one-stage and two-stage operations in batch mode. The maximum value of phytase activity was reached 107.0 U mL(-1) at induction temperature of 30°C. Yeast extract supplement demonstrated a significant increase on both protein concentration and phytase activity. The acetic acid (2 g L(-1)) presented in the modified synthetic medium demonstrated a significant decrease on expressed phytase activity. A two-stage batch operation enhanced the level of phytase activity from 306 to 1204 U mL(-1) in the 20 L of fermentation scale. An overall 3.7-fold improvement in phytase yield (35,375.72-1,31,617.50 U g(-1) DCW) was achieved in the two-stage operation.
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Repairing the ventral root is sufficient for simultaneous motor and sensory recovery in multiple complete cervical root transection injuries.
Life Sci.
PUBLISHED: 02-10-2014
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In multiple cervical root transection injuries, motor and sensory recovery has been demonstrated after repairing both dorsal and ventral roots with autologous grafts applied to the dorsal and ventral aspects, respectively. However, in clinical situations, autologous grafts may not be sufficient to repair both roots in this situation. In this study, the authors evaluated whether repairing ventral root alone is sufficient for simultaneous sensory and motor function recovery.
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Whey protein improves exercise performance and biochemical profiles in trained mice.
Med Sci Sports Exerc
PUBLISHED: 02-08-2014
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The objective of this study is to verify the beneficial effects of whey protein (WP) supplementation on health promotion and enhance exercise performance in an aerobic-exercise training protocol.
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Association between C-reactive protein, corrected QT interval and presence of QT prolongation in hypertensive patients.
Kaohsiung J. Med. Sci.
PUBLISHED: 02-01-2014
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C-reactive protein (CRP) and corrected QT (QTc) interval are predictors of cardiovascular disease. Whether CRP is associated with QTc interval and QT prolongation is unknown in hypertensive patients. We recruited hypertensive patients from a cardiovascular clinic in a tertiary medical center in Taiwan. All received standard 12-lead electrocardiogram examination. QT prolongation was defined as QTc interval ? 440 ms in men or ? 450 ms in women. High-sensitive CRP kits were used for the measurement of the CRP levels. A total of 466 consecutive patients were finally enrolled. Mean age was 60.6 ± 12.0 years. CRP level was correlated with QTc interval (p < 0.001) and presence of QT prolongation (p = 0.014). Multivariate regression analysis showed that CRP level (p = 0.001), age (p = 0.004), sex (p < 0.001), height (p = 0.001), low-density lipoprotein (p = 0.041), and QRS interval (p < 0.001) were associated with QTc interval. Furthermore, CRP level [odds ratio (OR) = 1.203, 95% confidence interval (CI) = 1.027-1.410, p = 0.022], age (OR = 1.040, 95% CI = 1.010-1.071, p = 0.009), waist (OR = 1.033, 95% CI = 1.000-1.066, p = 0.047), triglyceride (OR = 0.993, 95% CI = 0.987-0.999, p = 0.021) and QRS interval (OR = 1.046, 95% CI = 1.028-1.065, p < 0.001) independently predicted the presence of QT prolongation. Because CRP is an independent predictor of QTc interval and presence of QT prolongation, it could be considered in the risk assessment for hypertensive patients.
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The Epstein-Barr virus-encoded microRNA MiR-BART9 promotes tumor metastasis by targeting E-cadherin in nasopharyngeal carcinoma.
PLoS Pathog.
PUBLISHED: 02-01-2014
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MicroRNAs (miRNAs) are a family of small RNA molecules that negatively regulate the expression of protein-coding genes and play critical roles in orchestrating diverse cellular processes. This regulatory mechanism is also exploited by viruses to direct their life cycle and evade the host immune system. Epstein-Barr virus (EBV) is an oncogenic virus that is closely associated with multiple human diseases, including nasopharyngeal carcinoma (NPC), which is a highly metastatic type of tumor and is frequently reported in South Asia. Several viral proteins have been found to promote the migration and invasiveness of NPC cells. However, not all tumor tissues express these viral oncoproteins, suggesting that other mechanisms may contribute to the aggressive behavior of NPC tumor cells. A previous sequencing study by our group revealed that the EBV miRNA miR-BART9 was expressed at high levels in all EBV-positive NPC tissues. In the present study, we used gain- and loss-of-function approaches to investigate the effect of miR-BART9 in EBV-negative and EBV-positive NPC cells. We discovered that miR-BART9 promotes the migration and invasiveness of cultured NPC cells. The promigratory activity observed in vitro was manifested as an enhanced metastatic ability in vivo. Computational analysis revealed that miR-BART9 may target E-cadherin, a membrane protein that is pivotal in preserving cell-cell junctions and the epithelial phenotype. Through biochemical assays and functional rescue analysis, we confirmed that miR-BART9 specifically inhibits E-cadherin to induce a mesenchymal-like phenotype and promote the migration of NPC cells. These results indicated that miR-BART9 is a prometastatic viral miRNA and suggested that high levels of miR-BART9 in EBV-positive NPC cells may contribute to the aggressiveness of tumor cells.
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Rapid detection of hepatitis B virus variants associated with lamivudine and adefovir resistance by multiplex ligation-dependent probe amplification combined with real-time PCR.
J. Clin. Microbiol.
PUBLISHED: 01-31-2014
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Drug-resistant mutations of hepatitis B virus (HBV) are the major obstacles to successful therapy for chronic hepatitis B infection. Although there are many methods for detecting the antiviral drug-resistant mutations of HBV, their applications are restricted because of their shortcomings, such as low sensitivity, the time required, and the high cost. For this study, a multiplex ligation-dependent probe real-time PCR (MLP-RT-PCR) method was developed to simultaneously detect lamivudine (LAM)- and adefovir (ADV)-resistant HBV mutants (those with the mutations rtM204V/I, rtA181V/T, and rtN236T). The new method combined the high-throughput nature of multiplex ligation-dependent probe amplification (MLPA) with the rapid and sensitive detection of real-time PCR. In this report, MLP-RT-PCR was evaluated by detecting drug-resistant mutants in 116 patients with chronic hepatitis B infection. By MLP-RT-PCR analysis, LAM-resistant mutations were detected in 41 patients (35.3%), ADV-resistant mutations were detected in 17 patients (14.7%), and LAM- and-ADV-resistant mutations were detected in 5 patients (4.3%). Based on the results of MLP-RT-PCR, the mutations rtM204V, rtM204I, rtA181T, rtA181V, and rtN236T were 95.7% (111/116 patients), 98.3% (114/116 patients), 99.1% (115/116 patients), 98.3% (114/116 patients), and 99.1% (115/116 patients) concordant, respectively, with those of direct sequencing. The MLP-RT-PCR assay was more sensitive than direct sequencing for detecting mutations with low frequencies. Four samples containing the low-frequency (<10%) mutants were identified by MLP-RT-PCR and further confirmed by clonal sequencing. MLP-RT-PCR is a rapid and sensitive method that enables the detection of multidrug-resistant HBV mutations in clinical practice.
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A direct and polymer-free method for transferring graphene grown by chemical vapor deposition to any substrate.
ACS Nano
PUBLISHED: 01-31-2014
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We demonstrate a polymer-free method that can routinely transfer relatively large-area graphene to any substrate with advanced electrical properties and superior atomic and chemical structures as compared to the graphene sheets transferred with conventional polymer-assisted methods. The graphene films that are transferred with polymer-free method show high electrical conductance and excellent optical transmittance. Raman spectroscopy and X-ray/ultraviolet photoelectron spectroscopy also confirm the presence of high quality graphene sheets with little contamination after transfer. Atom-resolved images can be obtained using scanning tunneling microscope on as-transferred graphene sheets without additional cleaning process. The mobility of the polymer-free graphene monolayer is as high as 63,000 cm(2) V(-1) s(-1), which is 50% higher than the similar sample transferred with the conventional method. More importantly, this method allows us to place graphene directly on top of devices made of soft materials, such as organic and polymeric thin films, which widens the applications of graphene in soft electronics.
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Tacrolimus suppresses atopic dermatitis-associated cytokines and chemokines in monocytes.
J Microbiol Immunol Infect
PUBLISHED: 01-15-2014
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Calcineurin inhibitors (CNIs) exhibit remarkable efficacy in atopic dermatitis (AD). Tacrolimus, one type of CNI, is prevalently used to treat AD. AD is a chronic inflammatory disease that exhibits predominant infiltration of T-helper type 2 (Th2) cell in the acute phase and a mixed Th1 and Th0 cell pattern in chronic lesions. Cytokines such as tumor necrosis factor-? (TNF-?), Th2-related chemokines [e.g., macrophage-derived chemokine (MDC)/CCL22 and I-309/CCL1], Th1-related chemokines [e.g., interferon ?-induced protein 10 (IP-10)/CXCL10], and neutrophil chemoattractant growth-related oncogene-? (GRO-?)/CXCL1 are involved in the pathogenesis of AD. However, whether tacrolimus modulates the expression of AD-associated cytokines and chemokines remains unknown. The intracellular mechanisms of tacrolimus are also unclear.
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Label-free and high-sensitive detection of human breast cancer cells by aptamer-based leaky surface acoustic wave biosensor array.
Biosens Bioelectron
PUBLISHED: 01-10-2014
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A label-free and high-sensitive sensing technology for tumor cell recognition and detection was developed based on a novel 2 × 3 model of leaky surface acoustic wave (LSAW) aptasensor array. In this methodology, every resonator crystal unit of the LSAW aptasensor array had an individual oscillator circuit to work without mutual interference, and could oscillate independently with the phase shift stability of ± 0.15° in air phase and ± 0.3° in liquid phase. The aptamer was firstly assembled to the gold electrode surface of 100 MHz LiTaO3 piezoelectric crystal, which could effectively captured target cells (MCF-7 cells) based on the specific interaction between aptamer and the overexpression of MUC1 protein on tumor cell surface. The aptamer-cell complexes increased the mass loading of LSAW aptasensor and led to phase shifts of LSAW. The plot of phase shift against the logarithm of concentration of MCF-7 cells was linear over the range from 1 × 10(2) cells mL(-1) to 1 × 10(7) cells mL(-1) with a correlation coefficient of 0.994. The detection limit as low as 32 cells mL(-1) was achieved for MCF-7 cells. The LSAW aptasensor also exhibited excellent specificity and stability. In addition, this aptasensor could be regenerated for ten times without irreversible loss of activity. Therefore, the LSAW aptasensor may offer a promising approach for tumor cell detection and have great potential in clinical applications.
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Comparison of height- and weight-adjusted sarcopenia in a Taiwanese metropolitan older population.
Geriatr Gerontol Int
PUBLISHED: 01-09-2014
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The present population-based, cross-sectional study was carried out in communities in Taichung, Taiwan, to identify the prevalence of and the factors associated with sarcopenia, using the diagnostic criteria of the European Working Group on Sarcopenia in Older People, which requires the presence of low muscle mass and low muscle function.
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Epigenetic regulation in allergic diseases and related studies.
Asia Pac Allergy
PUBLISHED: 01-08-2014
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Asthma, a chronic inflammatory disorder of the airway, has features of both heritability as well as environmental influences which can be introduced in utero exposures and modified through aging, and the features may attribute to epigenetic regulation. Epigenetic regulation explains the association between early prenatal maternal smoking and later asthma-related outcomes. Epigenetic marks (DNA methylation, modifications of histone tails or noncoding RNAs) work with other components of the cellular regulatory machinery to control the levels of expressed genes, and several allergy- and asthma-related genes have been found to be susceptible to epigenetic regulation, including genes important to T-effector pathways (IFN-?, interleukin [IL] 4, IL-13, IL-17) and T-regulatory pathways (FoxP3). Therefore, the mechanism by which epigenetic regulation contributes to allergic diseases is a critical issue. In the past most published experimental work, with few exceptions, has only comprised small observational studies and models in cell systems and animals. However, very recently exciting and elegant experimental studies and novel translational research works were published with new and advanced technologies investigating epigenetic mark on a genomic scale and comprehensive approaches to data analysis. Interestingly, a potential link between exposure to environmental pollutants and the occurrence of allergic diseases is revealed recently, particular in developed and industrialized countries, and endocrine disrupting chemicals (EDCs) as environmental hormone may play a key role. This review addresses the important question of how EDCs (nonylphenol, 4 octylphenol, and phthalates) influences on asthma-related gene expression via epigenetic regulation in immune cells, and how anti-asthmatic agents prohibit expression of inflammatory genes via epigenetic modification. The discovery and validation of epigenetic biomarkers linking exposure to allergic diseases might lead to better epigenotyping of risk, prognosis, treatment prediction, and development of novel therapies.
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Comparative Analysis of Human ?D-Crystallin Aggregation under Physiological and Low pH Conditions.
PLoS ONE
PUBLISHED: 01-01-2014
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Cataract, a major cause of visual impairment worldwide, is the opacification of the eye's crystalline lens due to aggregation of the crystallin proteins. The research reported here is aimed at investigating the aggregating behavior of ?-crystallin proteins in various incubation conditions. Thioflavin T binding assay, circular dichroism spectroscopy, 1-anilinonaphthalene-8-sulfonic acid fluorescence spectroscopy, intrinsic (tryptophan) fluorescence spectroscopy, light scattering, and electron microscopy were used for structural characterization. Molecular dynamics simulations and bioinformatics prediction were performed to gain insights into the ?D-crystallin mechanisms of fibrillogenesis. We first demonstrated that, except at pH 7.0 and 37°C, the aggregation of ?D-crystallin was observed to be augmented upon incubation, as revealed by turbidity measurements. Next, the types of aggregates (fibrillar or non-fibrillar aggregates) formed under different incubation conditions were identified. We found that, while a variety of non-fibrillar, granular species were detected in the sample incubated under pH 7.0, the fibrillogenesis of human ?D-crystallin could be induced by acidic pH (pH 2.0). In addition, circular dichroism spectroscopy, 1-anilinonaphthalene-8-sulfonic acid fluorescence spectroscopy, and intrinsic fluorescence spectroscopy were used to characterize the structural and conformational features in different incubation conditions. Our results suggested that incubation under acidic condition led to a considerable change in the secondary structure and an enhancement in solvent-exposure of the hydrophobic regions of human ?D-crystallin. Finally, molecular dynamics simulations and bioinformatics prediction were performed to better explain the differences between the structures and/or conformations of the human ?D-crystallin samples and to reveal potential key protein region involved in the varied aggregation behavior. Bioinformatics analyses revealed that the initiation of amyloid formation of human ?D-crystallin may be associated with a region within the C-terminal domain. We believe the results from this research may contribute to a better understanding of the possible mechanisms underlying the pathogenesis of senile nuclear cataract.
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The benefits of endurance exercise and Tai Chi Chuan for the task-switching aspect of executive function in older adults: an ERP study.
Front Aging Neurosci
PUBLISHED: 01-01-2014
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This study was designed to determine the relationship between physical activity and the task-switching aspect of executive function by investigating the modulating roles of age, modality of physical activity, and type of cognitive function using behavioral and event-related potential (ERP) assessments. Sixty-four participants were assigned to one of four groups based on age and history of physical activity: older adults performing endurance exercise (OEE), older adults practicing Tai Chi Chuan (OTC), older adults with a sedentary lifestyle (OSL), and young adults (YA). Study participants completed a task-switching task under homogeneous and heterogeneous conditions while ERPs were recorded. The results revealed that YA had shortest reaction times compared with the three older adults groups, with OSL exhibiting the longest reaction time. YA also exhibited shorter P3 latency than OSL. No differences were observed in P3 amplitude between YA, OEE, and OTC; however, all three groups had significantly larger P3 amplitude compared with OSL in both task conditions. In conclusion, age and participation in physical activity influence the relationship between physical activity and task-switching, and a positive relationship was observed regardless of the modality of physical activity and type of cognitive function. Our ERP findings support the model of the scaffolding theory of aging and cognition (STAC) and suggest that regular participation in endurance exercise and Tai Chi Chuan may have equivalent beneficial effects on cognition at the behavioral and neuroelectric levels.
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Acute aerobic exercise increases cortical activity during working memory: a functional MRI study in female college students.
PLoS ONE
PUBLISHED: 01-01-2014
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There is increasing evidence that acute aerobic exercise is associated with improved cognitive function. However, neural correlates of its cognitive plasticity remain largely unknown. The present study examined the effect of a session of acute aerobic exercise on working memory task-evoked brain activity as well as task performance. A within-subjects design with a counterbalanced order was employed. Fifteen young female participants (M?=?19.56, SD?=?0.81) were scanned using functional magnetic resonance imaging while performing a working memory task, the N-back task, both following an acute exercise session with 20 minutes of moderate intensity and a control rest session. Although an acute session of exercise did not improve behavioral performance, we observed that it had a significant impact on brain activity during the 2-back condition of the N-back task. Specifically, acute exercise induced increased brain activation in the right middle prefrontal gyrus, the right lingual gyrus, and the left fusiform gyrus as well as deactivations in the anterior cingulate cortexes, the left inferior frontal gyrus, and the right paracentral lobule. Despite the lack of an effect on behavioral measures, significant changes after acute exercise with activation of the prefrontal and occipital cortexes and deactivation of the anterior cingulate cortexes and left frontal hemisphere reflect the improvement of executive control processes, indicating that acute exercise could benefit working memory at a macro-neural level. In addition to its effects on reversing recent obesity and disease trends, our results provide substantial evidence highlighting the importance of promoting physical activity across the lifespan to prevent or reverse cognitive and neural decline.
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Physical activity and working memory in healthy older adults: an ERP study.
Psychophysiology
PUBLISHED: 12-06-2013
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This study examined the effects of physical activity on working memory in older adults using both behavioral and neuroelectric measures. Older adults were assigned to either a higher or lower physical activity group, and event-related potentials were recorded during assessments of a modified Sternberg task. The results indicated that older adults in the higher physical activity group exhibited shorter response times, independent of the working memory load. Enhanced P3 and N1 amplitudes and a decreased P3 latency were observed in the higher physical activity group. These findings suggested that physical activity facilitates working memory by allocating more attentional resources and increasing the efficiency of evaluating the stimulus during the retrieval phase as well as engaging more attentional resources for the early discriminative processes during the encoding phase of a working memory task.
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Aberrantly hypermethylated Homeobox A2 derepresses metalloproteinase-9 through TBP and promotes invasion in Nasopharyngeal carcinoma.
Oncotarget
PUBLISHED: 11-19-2013
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Nasopharyngeal carcinoma (NPC) is notorious for its high invasiveness and metastatic ability. In this study, we identified a differential hypermethylated transcription repressor, Homeobox A2 (HOXA2), which may render NPC cells invasive and metastatic. Aberrant hypermethylation of HOXA2 led to low RNA expression in NPC tumors and cells. Addition of methylation inhibitor 5Aza restored HOXA2 RNA expression in NPC cells. Methylated HOXA2 promoter reduces the binding affinity of the transcriptional co-activator p300, causing transcriptionalrepression of HOXA2. In NPC cells, re-expression of ectopic HOXA2 wascorrelated with decreased invasive ability and reduced metalloproteinase MMP-9 RNA and protein expression. Promoter, ChIP and DNA-pull down assays indicated that HOXA2 competes with the transcription activator, TATA-box binding protein (TBP) for a recognition sequence near the MMP-9 transcription start site, and suppresses MMP-9 transcription. Thus, HOXA2 acts as a suppressor or TBP-antagonist to inhibit MMP-9 expression; while methylation-mediated inactivation of HOXA2 in NPC derepresses MMP-9 production and increases invasion of NPC cells. In NPC plasma samples, increased plasma EBV copy number was correlated with increased in cell-free HOXA2 hypermethylation and elevated MMP-9 levels. Plasma EBV DNA and methylated cell-free HOXA2 can be used as biomarkers for monitoring NPC treatment.
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13% Efficiency Hybrid Organic/Silicon-Nanowire Heterojunction Solar Cell via Interface Engineering.
ACS Nano
PUBLISHED: 11-19-2013
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Interface carrier recombination currently hinders the performance of hybrid organic-silicon heterojunction solar cells for high-efficiency low-cost photovoltaics. Here, we introduce an intermediate 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC) layer into hybrid heterojunction solar cells based on silicon nanowires (SiNWs) and conjugate polymer poly(3,4-ethylenedioxy-thiophene):poly(styrenesulfonate) (PEDOT:PSS). The highest power conversion efficiency reaches a record 13.01%, which is largely ascribed to the modified organic surface morphology and suppressed saturation current that boost the open-circuit voltage and fill factor. We show that the insertion of TAPC increases the minority carrier lifetime because of an energy offset at the heterojunction interface. Furthermore, X-ray photoemission spectroscopy reveals that TAPC can effectively block the strong oxidation reaction occurring between PEDOT:PSS and silicon, which improves the device characteristics and assurances for reliability. These learnings point toward future directions for versatile interface engineering techniques for the attainment of highly efficient hybrid photovoltaics.
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High-efficiency small-molecule-based organic light emitting devices with solution processes and oxadiazole-based electron transport materials.
ACS Appl Mater Interfaces
PUBLISHED: 10-31-2013
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We demonstrate high-efficiency small-molecule-based white phosphorescent organic light emitting diodes (PHOLEDs) by single-active-layer solution-based processes with the current efficiency of 17.3 cdA(-1) and maximum luminous efficiency of 8.86 lmW(-1) at a current density of 1 mA cm(-2). The small-molecule based emitting layers are codoped with blue and orange phosphorescent dyes. We show that the presence of CsF/Al at cathodes not only improves electron transport in oxadiazole-containing electron transport layers (ETLs), but also facilitates electron injection through the reacted oxadiazole moiety to reduce interface resistance, which results in the enhancement of current efficiency. By selecting oxadiazole-based materials as ETLs with proper electron injection layer (EIL)/cathode structures, the brightness and efficiency of white PHOLEDs are significantly improved.
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Effects of Cardiorespiratory Fitness Enhancement on Deficits in Visuospatial Working Memory in Children with Developmental Coordination Disorder: A Cognitive Electrophysiological Study.
Arch Clin Neuropsychol
PUBLISHED: 10-29-2013
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The present study aimed to explore the effectiveness of chronic aerobic exercise intervention on the behavioral and neuroelectric performances of children with developmental coordination disorder (DCD) when carrying out a visuospatial working memory (VSWM) task. Twenty typically developing children and 40 children with DCD, equally divided into DCD-training and DCD nontraining groups, performed the cognitive task with concomitant event-related potential recording before and after 16 weeks of endurance training. Results indicated that the children with DCD displayed VSWM deficits with regard to behavioral performance (i.e., slower reaction time and low accuracy rate) and the neuroelectric indices (i.e., smaller P3 and pSW amplitudes) during the retrieval-process phase as reported in previous studies. However, after the exercise intervention, DCD-training group showed significantly higher accuracy rates and enhanced P3 amplitudes during the encoding and retrieval-process phases, compared with their pre-training performances. These findings suggest that increased cardiorespiratory fitness could effectively improve the performance of the VSWM task in children with DCD, by enabling the allocation of greater working memory resources related to encoding and retrieval.
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Modeling RAS Phenotype in Colorectal Cancer Uncovers Novel Molecular Traits of RAS Dependency and Improves Prediction of Response to Targeted Agents in Patients.
Clin. Cancer Res.
PUBLISHED: 10-29-2013
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KRAS wild-type status is an imperfect predictor of sensitivity to anti-EGF receptor (EGFR) monoclonal antibodies in colorectal cancer, motivating efforts to identify novel molecular aberrations driving RAS. This study aimed to build a quantitative readout of RAS pathway activity to (i) uncover molecular surrogates of RAS activity specific to colorectal cancer, (ii) improve the prediction of cetuximab response in patients, and (iii) suggest new treatment strategies.EXPERIMENTAL DESIGN: A model of RAS pathway activity was trained in a large colorectal cancer dataset and validated in three independent colorectal cancer patient datasets. Novel molecular traits were inferred from The Cancer Genome Atlas colorectal cancer data. The ability of the RAS model to predict resistance to cetuximab was tested in mouse xenografts and three independent patient cohorts. Drug sensitivity correlations between our model and large cell line compendiums were performed.RESULTS: The performance of the RAS model was remarkably robust across three validation datasets. (i) Our model confirmed the heterogeneity of the RAS phenotype in KRAS wild-type patients, and suggests novel molecular traits driving its phenotype (e.g., MED12 loss, FBXW7 mutation, MAP2K4 mutation). (ii) It improved the prediction of response and progression-free survival (HR, 2.0; P < 0.01) to cetuximab compared with KRAS mutation (xenograft and patient cohorts). (iii) Our model consistently predicted sensitivity to MAP-ERK kinase (MEK) inhibitors (P < 0.01) in two cell panel screens.CONCLUSIONS: Modeling the RAS phenotype in colorectal cancer allows for the robust interrogation of RAS pathway activity across cell lines, xenografts, and patient cohorts. It demonstrates clinical utility in predicting response to anti-EGFR agents and MEK inhibitors. Clin Cancer Res; 1-8. ©2013 AACR.
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Neuropsychological functions and quality of life in survived patients with intracranial germ cell tumors after treatment.
Neuro-oncology
PUBLISHED: 10-06-2013
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The notable survival chances of intracranial germ cell tumors (icGCTs) lead to a rising concern over long-term neurocognitive outcome. Yet, prior evidence related to this issue fails to provide a comprehensive examination of the effects of tumor location and radiotherapy. We attempt to explore their impacts on the neuropsychological functions and life quality in children with icGCT after multimodality treatments.
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Executive function during acute exercise: the role of exercise intensity.
J Sport Exerc Psychol
PUBLISHED: 08-23-2013
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This study was designed to examine the modulation of executive functions during acute exercise and to determine whether exercise intensity moderates this relationship. Eighty college-aged adults were recruited and randomly assigned into one of the four following groups: control, 30%, 50%, and 80% heart rate reserve. The Wisconsin Card Sorting Test (WCST) was administered during each intervention. The results indicated that the majority of the WCST performances were impaired in the high exercise intensity group relative to those of the other three groups, whereas similar performance rates were maintained in the low- and moderate-intensity groups. These findings suggest that transient hypofrontality occurs during high-intensity exercise, but not during low- and moderate-intensity exercises. Future research aimed at employing the dual-mode theory, and applying the reticular-activating hypofrontality model is recommended to further the current knowledge.
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Development and validation of a novel leaky surface acoustic wave immunosensor array for label-free and high-sensitive detection of cyclosporin A in whole-blood samples.
Biosens Bioelectron
PUBLISHED: 08-05-2013
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This manuscript described a novel 2×3 model of leaky surface acoustic wave (LSAW) immunosensor array for label-free and high-sensitive detection of Cyclosporin A (CsA) in whole-blood samples. In this technique, every resonator crystal unit of the LSAW immunosensor array had an individual oscillator circuit to work without mutual interference. The LSAW immunosensor was first immobilized with protein A from Staphylococcus aureus and monoclonal anti-CsA antibody on the gold electrode surface of 100MHz LiTaO3 piezoelectric crystals, which then captured the CsA. The CsA increased the mass loading of LSAW immunosensor and leaded to phase shifts of LSAW. Consequently, under optimal conditions, the designed LSAW immunosensor exhibited a detection limit of 0.89ng/mL, quantification limit of 2.96ng/mL, and wide dynamic linear range from 1ng/mL to 1000ng/mL for CsA detection. Application of the LSAW immunosensor array to clinical sample revealed that consistency and comparability between LSAW immunosensor and the enzyme multiplied immunoassay method were good. Moreover, the immunosensor could be regenerated for ten times without appreciable loss of activity. Therefore, the self-designed LSAW immunosensor array provided a rapid, accurate, label-free, easy handling, and dynamic real-time method for the detection of immunosuppressive drugs in clinical laboratory.
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Low-molecular-mass secretome profiling identifies C-C motif chemokine 5 as a potential plasma biomarker and therapeutic target for nasopharyngeal carcinoma.
J Proteomics
PUBLISHED: 07-07-2013
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Cancer cell secretome profiling has been shown to be a promising strategy for identifying potential body fluid-accessible cancer biomarkers and therapeutic targets. However, very few reports have investigated low-molecular-mass (LMr) proteins (<15kDa) in the cancer cell secretome. In the present study, we applied tricine-SDS-gel-assisted fractionation in conjunction with LC-MS/MS to systemically identify LMr proteins in the secretomes of three nasopharyngeal carcinoma (NPC) cell lines. We examined two NPC tissue transcriptome datasets to identify LMr genes/proteins that are highly upregulated in NPC tissues and also secreted/released from NPC cells, obtaining 35 candidates. We verified the overexpression of four targets (LSM2, SUMO1, RPL22, and CCL5) in NPC tissues by immunohistochemistry and demonstrated elevated plasma levels of two targets (S100A2 and CCL5) in NPC patients by ELISA. Notably, plasma CCL5 showed good power (AUC 0.801) for discriminating NPC patients from healthy controls. Additionally, functional assays revealed that CCL5 promoted migration of NPC cells, an effect that was effectively blocked by CCL5-neutralizing antibodies and maraviroc, a CCL5 receptor antagonist. Collectively, our data indicate the feasibility of the tricine-SDS-gel/LC-MS/MS approach for efficient identification of LMr proteins from cancer cell secretomes, and suggest that CCL5 is a potential plasma biomarker and therapeutic target for NPC.
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Interface-induced topological insulator transition in GaAs/Ge/GaAs quantum wells.
Phys. Rev. Lett.
PUBLISHED: 07-03-2013
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We demonstrate theoretically that interface engineering can drive germanium, one of the most commonly used semiconductors, into a topological insulating phase. Utilizing giant electric fields generated by charge accumulation at GaAs/Ge/GaAs opposite semiconductor interfaces and band folding, the new design can reduce the sizable gap in Ge and induce large spin-orbit interaction, which leads to a topological insulator transition. Our work provides a new method to realize topological insulators in commonly used semiconductors and suggests a promising approach to integrate it in well-developed semiconductor electronic devices.
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Effect of taxane-based neoadjuvant chemotherapy on fibroglandular tissue volume and percent breast density in the contralateral normal breast evaluated by 3T MR.
NMR Biomed
PUBLISHED: 07-01-2013
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The aim of this study was to evaluate the change of breast density in the normal breast of patients receiving neoadjuvant chemotherapy (NAC). Forty-four breast cancer patients were studied. MRI acquisition was performed before treatment (baseline), and 4 and 12 weeks after treatment. A computer-algorithm-based program was used to segment breast tissue and calculate breast volume (BV), fibroglandular tissue volume (FV), and percent density (PD) (the ratio of FV over BV × 100%). The reduction of FV and PD after treatment was compared with baseline using paired t-tests with a Bonferroni-Holm correction. The association of density reduction with age was analyzed. FV and PD after NAC showed significant decreases compared with the baseline. FV was 110.0 ml (67.2, 189.8) (geometric mean (interquartile range)) at baseline, 104.3 ml (66.6, 164.4) after 4 weeks (p < 0.0001), and 94.7 ml (60.2, 144.4) after 12 weeks (comparison with baseline, p < 0.0001; comparison with 4 weeks, p = 0.016). PD was 11.2% (6.4, 22.4) at baseline, 10.6% (6.6, 20.3) after 4 weeks (p < 0.0001), and 9.7% (6.2, 17.9) after 12 weeks (comparison with baseline, p = 0.0001; comparison with 4 weeks, p = 0.018). Younger patients tended to show a higher density reduction, but overall correlation with age was only moderate (r = 0.28 for FV, p = 0.07, and r = 0.52 for PD, p = 0.0003). Our study showed that breast density measured from MR images acquired at 3T MR can be accurately quantified using a robust computer-aided algorithm based on non-parametric non-uniformity normalization (N3) and an adaptive fuzzy C-means algorithm. Similar to doxorubicin and cyclophosphamide regimens, the taxane-based NAC regimen also caused density atrophy in the normal breast and showed reduction in FV and PD. The effect of breast density reduction was age related and duration related. Copyright © 2013 John Wiley & Sons, Ltd.
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Motor ability and inhibitory processes in children with ADHD: a neuroelectric study.
J Sport Exerc Psychol
PUBLISHED: 06-27-2013
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The purpose of the current study was to examine the relationship between motor ability and response inhibition using behavioral and electrophysiological indices in children with ADHD. A total of 32 participants were recruited and underwent a motor ability assessment by administering the Basic Motor Ability Test-Revised (BMAT) as well as the Go/No-Go task and event-related potential (ERP) measurements at the same time. The results indicated that the BMAT scores were positively associated with the behavioral and ERP measures. Specifically, the BMAT average score was associated with a faster reaction time and higher accuracy, whereas higher BMAT subset scores predicted a shorter P3 latency in the Go condition. Although the association between the BMAT average score and the No-Go accuracy was limited, higher BMAT average and subset scores predicted a shorter N2 and P3 latency and a larger P3 amplitude in the No-Go condition. These findings suggest that motor abilities may play roles that benefit the cognitive performance of ADHD children.
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Leukemia inhibitory factor promotes nasopharyngeal carcinoma progression and radioresistance.
J. Clin. Invest.
PUBLISHED: 04-04-2013
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Radioresistance of EBV-associated nasopharyngeal carcinoma (NPC) is associated with poor prognosis for patients with this form of cancer. Here, we found that NPC patients had increased serum levels of leukemia inhibitory factor (LIF) and that higher LIF levels correlated with local tumor recurrence. Furthermore, in vitro studies with NPC cells and in vivo xenograft mouse studies demonstrated that LIF critically contributes to NPC tumor growth and radioresistance. Using these model systems, we found that LIF treatment activated the mTORC1/p70S6K signaling pathway, enhanced tumor growth, inhibited DNA damage responses, and enhanced radioresistance. Treatment with either soluble LIF receptor (sLIFR), a LIF antagonist, or the mTOR inhibitor rapamycin reversed LIF-mediated effects, resulting in growth arrest and increased sensitivity to ? irradiation. Immunohistochemical (IHC) analyses of human NPC biopsies revealed that LIF and LIFR were overexpressed in tumor cells and that LIF expression correlated with the presence of the activated p-p70S6K. Finally, we found that the EBV-encoded protein latent membrane protein 1 (LMP1) enhances LIF production. Together, our findings indicate that LIF promotes NPC tumorigenesis and suggest that serum LIF levels may predict local recurrence and radiosensitivity in NPC patients.
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Serum levels of chemokine (C-X-C motif) ligand 9 (CXCL9) are associated with tumor progression and treatment outcome in patients with oral cavity squamous cell carcinoma.
Oral Oncol.
PUBLISHED: 03-28-2013
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The aim of this cohort study was to examine the role of chemokine (C-X-C motif) ligand 9 (CXCL9) on oral cavity squamous cell carcinoma (OSCC).
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Prognostic implications of post-therapy (18)F-FDG PET in patients with locoregionally advanced nasopharyngeal carcinoma treated with chemoradiotherapy.
Ann Nucl Med
PUBLISHED: 03-16-2013
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Reliable prognostic factors that serve as a guide to follow-up of patients with locoregionally advanced nasopharyngeal carcinoma (NPC) have not yet been identified. We sought to investigate the prognostic implications of post-therapy PET in patients with NPC treated with chemoradiotherapy.
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Exercise mode and executive function in older adults: an ERP study of task-switching.
Brain Cogn
PUBLISHED: 03-08-2013
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The purpose of this study was to investigate the relationship between exercise mode and executive function and its effect on behavior and neuroelectric activity. Forty-eight older adults were classified into open-skill, closed-skill, and irregular exercise groups based on their experience of exercise participation. Executive function was measured via a task-switching paradigm, in which the behavioral indices and event-related potentials elicited by task-switching were assessed. The results revealed that the exercise groups, regardless of the exercise mode, exhibited faster reaction times in both global and local switches than the irregular exercise group, regardless of the within-task conditions. Similarly, larger P3 amplitudes were observed in both exercise groups compared to the irregular exercise group. Moreover, additional facilitation effects of open-skill exercises on global switch costs were observed, whereas no differences in local switch costs were found among the three groups. The results replicate previous studies that have reported generally improved executive function after participation in exercises; additionally, they extend the current knowledge by indicating that these cognitive improvements in specific aspects of executive function could also be obtained from open-skill exercises.
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Lentivirus-mediated RNA interference targeting the H19 gene inhibits cell proliferation and apoptosis in human choriocarcinoma cell line JAR.
BMC Cell Biol.
PUBLISHED: 03-05-2013
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H19 is a paternally imprinted gene that has been shown to be highly expressed in the trophoblast tissue. Results from previous studies have initiated a debate as to whether noncoding RNA H19 acts as a tumor suppressor or as a tumor promotor in trophoblast tissue. In the present study, we developed lentiviral vectors expressing H19-specific small interfering RNA (siRNA) to specifically block the expression of H19 in the human choriocarcinoma cell line JAR. Using this approach, we investigated the impact of the H19 gene on the proliferation, invasion and apoptosis of JAR cells. Moreover, we examined the effect of H19 knockdown on the expression of insulin-like growth factor 2 (IGF2), hairy and enhancer of split homologue-1 (HES-1) and dual-specific phosphatase 5 (DUSP5) genes.
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Highly sensitive ammonia sensor with organic vertical nanojunctions for noninvasive detection of hepatic injury.
Anal. Chem.
PUBLISHED: 03-05-2013
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We successfully demonstrate the first solid-state sensor to have reliable responses to breath ammonia of rat. For thioacetamide (TAA)-induced hepatopathy rats, we observe that the proposed sensor can detect liver that undergoes acute-moderate hepatopathy with a p-value less than 0.05. The proposed sensor is an organic diode with vertical nanojunctions produced by using low-cost colloidal lithography. Its simple structure and low production cost facilitates the development of point-of-care technology. We also anticipate that the study is a starting point for investigating sophisticated breath-ammonia-related disease models.
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Pretreatment interleukin-6 serum levels are associated with patient survival for oral cavity squamous cell carcinoma.
Otolaryngol Head Neck Surg
PUBLISHED: 02-20-2013
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This study aims to determine the role of serum interleukin-6 concentration for oral cavity squamous cell carcinomas.
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Molecular aspects of Dravet syndrome patients in Taiwan.
Clin. Chim. Acta
PUBLISHED: 02-10-2013
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Dravet syndrome (DS) is a rare form of intractable epilepsy. Children with DS often start having seizures in infancy, and gradually develop other seizure types. Several studies have demonstrated that certain gene mutations and submicroscopic copy number variations (CNV) in DS patients are strongly associated with intractable epilepsy. In this study, directed DNA sequencing and microarray technology were used to investigate genomic variations in DS patients.
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Clinical scenario of EBV DNA follow-up in patients of treated localized nasopharyngeal carcinoma.
Oral Oncol.
PUBLISHED: 02-08-2013
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In this study, we investigated the usefulness and limitations of EBV-DNA follow-up in patients who had treated localized nasopharyngeal carcinoma.
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High density unaggregated Au nanoparticles on ZnO nanorod arrays function as efficient and recyclable photocatalysts for environmental purification.
Small
PUBLISHED: 02-07-2013
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Photodegradation of organic pollutants in aqueous solution is a promising method for environmental purification. Photocatalysts capable of promoting this reaction are often composed of noble metal nanoparticles deposited on a semiconductor. Unfortunately, the separation of these semiconductor-metal nanopowders from the treated water is very difficult and energy consumptive, so their usefulness in practical applications is limited. Here, a precisely controlled synthesis of a large-scale and highly efficient photocatalyst composed of monolayered Au nanoparticles (AuNPs) chemically bound to vertically aligned ZnO nanorod arrays (ZNA) through a bifunctional surface molecular linker is demonstrated. Thioctic acid with sufficient steric stabilization is used as a molecular linker. High density unaggregated AuNPs bonding on entire surfaces of ZNA are successfully prepared on a conductive film/substrate, allowing easy recovery and reuse of the photocatalysts. Surprisingly, the ZNA-AuNPs heterostructures exhibit a photodegradation rate 8.1 times higher than that recorded for the bare ZNA under UV irradiation. High density AuNPs, dispersed perfectly on the ZNA surfaces, significantly improve the separation of the photogenerated electron-hole pairs, enlarge the reaction space, and consequently enhance the photocatalytic property for degradation of chemical pollutants. Photoelectron, photoluminescence and photoconductive measurements confirm the discussion on the charge carrier separation and photocatalytic experimental data. The demonstrated higher photodegradation rates demonstrated indicate that the ZNA-AuNPs heterostructures are candidates for the next-generation photocatalysts, replacing the conventional slurry photocatalysts.
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What is Visualize?

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

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

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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.