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Find video protocols related to scientific articles indexed in Pubmed.
Low-Dose Ionizing Radiation Induces Direct Activation of Nature Killer Cells and Provides a Novel Approach for Adoptive Cellular Immunotherapy.
Cancer Biother. Radiopharm.
PUBLISHED: 11-18-2014
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Abstract Recent evidence indicates that limited availability and cytotoxicity have restricted the development of natural killer (NK) cells in adoptive cellular immunotherapy (ACI). While it has been reported that low-dose ionizing radiation (LDIR) could enhance the immune response in animal studies, the influence of LDIR at the cellular level has been less well defined. In this study, the authors aim to investigate the direct effects of LDIR on NK cells and the potential mechanism, and explore the application of activation and expansion of NK cells by LDIR in ACI. The authors found that expansion and cytotoxicity of NK cells were markedly augmented by LDIR. The levels of IFN-? and TNF-? in the supernatants of cultured NK cells were significantly increased after LDIR. Additionally, the effect of the P38 inhibitor (SB203580) significantly decreased the expanded NK cell cytotoxicity, cytokine levels, and expression levels of FasL and perforin. These findings indicate that LDIR induces a direct expansion and activation of NK cells through possibly the P38-MAPK pathway, which provides a potential mechanism for stimulation of NK cells by LDIR and a novel but simplified approach for ACI.
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Binary electroosmotic-pump nanoflow gradient generator for miniaturized high performance liquid chromatography.
Anal. Chem.
PUBLISHED: 11-18-2014
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High performance liquid chromatography (HPLC) plays an important role in biotechnology, and a majority of chromatographic separations uses gradient elution. While gradient generators can be built in different formats, binary-pumps or quaternary-pumps are most frequently used for gradient generator constructions. We have recently developed a high-pressure electroosmotic pump (EOP); the pump can be manufactured at a cost of a few hundred dollars. However, it is challenging to use this pump to deliver a gradient eluent directly. In this study, we first improve the monolith preparation by applying a pressure to the monomer solution during polymerization. We assemble a binary EOP gradient generator and discuss the relationship between gradient profile and voltage applied on EOP. We demonstrate the feasibility of binary EOP gradient generator for generating smooth and reproducible nanoflow gradient. After integrating the gradient generator into a miniaturized HPLC, we use the HPLC for separating peptide mixtures from trypsin-digested proteins. The performance comparison between the above miniaturized HPLC and an Agilent 1200 HPLC exhibits comparable efficiencies, resolutions, and peak capacities.
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Association of Inpatient vs Outpatient Onset of ST-Elevation Myocardial Infarction With Treatment and Clinical Outcomes.
JAMA
PUBLISHED: 11-17-2014
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Reperfusion times for ST-elevation myocardial infarction (STEMI) occurring in outpatients have improved significantly, but quality improvement efforts have largely ignored STEMI occurring in hospitalized patients (inpatient-onset STEMI).
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Retinal Toxicity Induced by a Novel ?-secretase Inhibitor in the Sprague-Dawley Rat.
Toxicol Pathol
PUBLISHED: 11-02-2014
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?-Secretase 1 (BACE1) represents an attractive target for the treatment of Alzheimer's disease. In the course of development of a novel small molecule BACE1 inhibitor (AMG-8718), retinal thinning was observed in a 1-month toxicity study in the rat. To further understand the lesion, an investigational study was conducted whereby rats were treated daily with AMG-8718 for 1 month followed by a 2-month treatment-free phase. The earliest detectable change in the retina was an increase in autofluorescent granules in the retinal pigment epithelium (RPE) on day 5; however, there were no treatment-related light microscopic changes observed in the neuroretina and no changes observed by fundus autofluorescence or routine ophthalmoscopic examination after 28 days of dosing. Following 2 months of recovery, there was significant retinal thinning attributed to loss of photoreceptor nuclei from the outer nuclear layer. Electroretinographic changes were observed as early as day 14, before any microscopic evidence of photoreceptor loss. BACE1 knockout rats were generated and found to have normal retinal morphology indicating that the retinal toxicity induced by AMG-8718 was likely off-target. These results suggest that AMG-8718 impairs phagolysosomal function in the rat RPE, which leads to photoreceptor dysfunction and ultimately loss of photoreceptors.
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[Effect of economic structure adjustment on pollution emission: a case study of COD].
Huan Jing Ke Xue
PUBLISHED: 10-24-2014
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Economic structure adjustment is an important means to reduce the emissions of pollutants. For quantitative analysis of the effect of economic structure adjustment on the reduction of pollution emission, the country was divided into four sub-regions, eastern, northeastern, central and western, and the industry was divided into 39 sectors. Taking chemical oxygen demand (COD) as an example, the influences of regional structure and industry structure adjustment on total emission reduction and emission intensity were analyzed through building a model. The results showed that, in 2000-2010: (1) COD emissions in China were reduced from 1 445 x 10(4) t to 1 238 x 10(4) t, with a total emission of 14 950 x 10(4) t in 11 years, among which the emissions from eastern area occupied the largest proportion, accounting for 35.6%. (2) In the industrial COD emissions, emission from paper and paper products was the largest, accounting for 35.8% of the industrial COD emissions. (3) The economic structure changes in the four areas reduced the COD emissions by 420 x 10(4) t, resulting in a decrease of 1.29% in COD emission intensity. (4) Industrial internal structure changes reduced the COD emissions by 533 x 10(4) t, leading to a decrease of 3.1% in COD emission intensity. The research results have certain reference value in guiding the Chinese economic structure adjustment and achieving the targets of energy-saving and emission reduction.
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Orphan nuclear receptor TR3/Nur77 improves wound healing by upregulating the expression of integrin ?4.
FASEB J.
PUBLISHED: 10-19-2014
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Tissue repair/wound healing, in which angiogenesis plays an important role, is a critical step in many diseases including chronic wound, myocardial infarction, stroke, cancer, and inflammation. Recently, we were the first to report that orphan nuclear receptor TR3/Nur77 is a critical mediator of angiogenesis and its associated microvessel permeability. Tumor growth and angiogenesis induced by VEGF-A, histamine, and serotonin are almost completely inhibited in Nur77 knockout mice. However, it is not known whether TR3/Nur77 plays any roles in wound healing. In these studies, skin wound-healing assay was performed in 3 types of genetically modified mice having various Nur77 activities. We found that ectopic induction of Nur77 in endothelial cells of mice is sufficient to improve skin wound healing. Although skin wound healing in Nur77 knockout mice is comparable to the wild-type control mice, the process is significantly delayed in the EC-Nur77-DN mice, in which a dominant negative Nur77 mutant is inducibly and specifically expressed in mouse endothelial cells. By a loss-of-function assay, we elucidate a novel feed-forward signaling pathway, integrin ?4 ? PI3K ? Akt ? FAK, by which TR3 mediates HUVEC migration. Furthermore, TR3/Nur77 regulates the expression of integrin ?4 by targeting its promoter activity. In conclusion, expression of TR3/Nur77 improves wound healing by targeting integrin ?4. TR3/Nur77 is a potential candidate for proangiogenic therapy. The results further suggest that TR3/Nur77 is required for pathologic angiogenesis but not for developmental/physiologic angiogenesis and that Nur77 and its family members play a redundant role in normal skin wound healing.-Niu, G., Ye, T., Qin, L., Bourbon, P. M., Chang, C., Zhao, S., Li, Y., Zhou, L., Cui, P., Rabinovitz, I., Mercurio, A. M., Zhao, D., Zeng, H. Orphan nuclear receptor TR3/Nur77 improves wound healing by upregulating the expression of integrin ?4.
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Anisotropic growth-induced synthesis of dual-compartment janus mesoporous silica nanoparticles for bimodal triggered drugs delivery.
J. Am. Chem. Soc.
PUBLISHED: 10-07-2014
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Multifunctional dual-compartment Janus mesoporous silica nanocomposites of UCNP@SiO2@mSiO2&PMO (UCNP = upconversion nanoparticle, PMO = periodic mesoporous organosilica) containing core@shell@shell structured UCNP@SiO2@mSiO2 nanospheres and PMO single-crystal nanocubes have been successfully synthesized via a novel anisotropic island nucleation and growth approach with the ordered mesostructure. The asymmetric Janus nanocomposites show a very uniform size of ?300 nm and high surface area of ?1290 m(2)/g. Most importantly, the Janus nanocomposites possess the unique dual independent mesopores with different pore sizes (2.1 nm and 3.5-5.5 nm) and hydrophobicity/hydrophilicity for loading of multiple guests. The distinct chemical properties of the silica sources and the different mesostructures of the dual-compartments are the necessary prerequisites for the formation of the Janus nanostructure. With the assistance of the near-infrared (NIR) to ultraviolet/visible (UV-vis) optical properties of UCNPs and heat-sensitive phase change materials, the dual-compartment Janus mesoporous silica nanocomposites can be further applied into nanobiomedicine for heat and NIR light bimodal-triggered dual-drugs controllable release. It realizes significantly higher efficiency for cancer cell killing (more than 50%) compared to that of the single-triggered drugs delivery system (?25%).
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Light extraction of trapped optical modes in polymer light-emitting diodes with nanoimprinted double-pattern gratings.
ACS Appl Mater Interfaces
PUBLISHED: 10-03-2014
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Despite the rapid development of polymer light-emitting diodes (PLEDs), the overall device efficiency is still limited because ?80% of the generated light is trapped in a conventional device architecture by the high refractive index of organic materials and the optical confinement and internal reflection. The implementation of the energy dissipation compensation techniques is urgently required for further enhancement in the efficiency of PLEDs. Here, we demonstrate that incorporating the double-pattern Bragg gratings in the organic layers with soft nanoimprinting lithography can dramatically enhance the light extraction of trapped optical modes in PLEDs. The resulting efficiency is 1.35 times that of a conventional device with a flat architecture used as a comparison. The experimental and theoretical analyses indicate that the enhanced out-coupling efficiency is attributed to the combination of the ordinary Bragg scattering, the guided-mode resonance (GMR), surface plasmon polariton (SPP) modes, and the hybrid anticross coupling between GMR and SPP, leading to the extraordinary efficient photo flux that can transfer in direction of the leaky modes. We anticipate that our method provides a new pathway for precisely manipulating nanoscale optical fields and could enable the integration of different optical modes in PLEDs for the viable applications.
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Single-Junction Polymer Solar Cells Exceeding 10% Power Conversion Efficiency.
Adv. Mater. Weinheim
PUBLISHED: 10-01-2014
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A single-junction polymer solar cell with an efficiency of 10.1% is demonstrated by using deterministic aperiodic nanostructures for broadband light harvesting with optimum charge extraction. The performance enhancement is ascribed to the self-enhanced absorption due to collective effects, including the pattern-induced anti-reflection, light scattering as well as surface plasmonic resonance, together with a minimized recombination probability.
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Involvement of GABA Transporters in Atropine-Treated Myopic Retina As Revealed by iTRAQ Quantitative Proteomics.
J. Proteome Res.
PUBLISHED: 10-01-2014
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Atropine, a muscarinic antagonist, is known to inhibit myopia progression in several animal models and humans. However, the mode of action is not established yet. In this study, we compared quantitative iTRAQ proteomic analysis in the retinas collected from control and lens-induced myopic (LIM) mouse eyes treated with atropine. The myopic group received a (-15D) spectacle lens over the right eye on postnatal day 10 with or without atropine eye drops starting on postnatal day 24. Axial length was measured by optical low coherence interferometry (OLCI), AC-Master, and refraction was measured by automated infrared photorefractor at postnatal 24, 38, and 52 days. Retinal tissue samples were pooled from six eyes for each group. The experiments were repeated twice, and technical replicates were also performed for liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. MetaCore was used to perform protein profiling for pathway analysis. We identified a total of 3882 unique proteins with <1% FDR by analyzing the samples in replicates for two independent experiments. This is the largest number of mouse retina proteome reported to date. Thirty proteins were found to be up-regulated (ratio for myopia/control > global mean ratio + 1 standard deviation), and 28 proteins were down-regulated (ratio for myopia/control < global mean ratio - 1 standard deviation) in myopic eyes as compared with control retinas. Pathway analysis using MetaCore revealed regulation of ?-aminobutyric acid (GABA) levels in the myopic eyes. Detailed analysis of the quantitative proteomics data showed that the levels of GABA transporter 1 (GAT-1) were elevated in myopic retina and significantly reduced after atropine treatment. These results were further validated with immunohistochemistry and Western blot analysis. In conclusion, this study provides a comprehensive quantitative proteomic analysis of atropine-treated mouse retina and suggests the involvement of GABAergic signaling in the antimyopic effects of atropine in mouse eyes. The GABAergic transmission in the neural retina plays a pivotal role in the maintenance of axial eye growth in mammals.
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Obesity, islet cell autoimmunity and cardiovascular risk factors in youth at onset of type 1 autoimmune diabetes.
J. Clin. Endocrinol. Metab.
PUBLISHED: 09-25-2014
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The current increase in childhood Type 1 diabetes (T1D) and obesity has led to two conflicting hypotheses and conflicting reports regarding the effects of overweight on initiation and spreading of islet cell autoimmunity vs. earlier clinical manifestation of preexisting autoimmune ?-cell damage driven by excess weight.
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Influence of early zoledronic acid administration on bone marrow fat in ovariectomized rats.
Endocrinology
PUBLISHED: 09-22-2014
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Although the primary target cell of bisphosphonates is the osteoclast, increasing attention is being given to other effector cells influenced by bisphosphonates, such as osteoblasts and marrow adipocytes. Early zoledronic acid (ZA) treatment to ovariectomized (OVX) rats has been found to fully preserve bone microarchitecture over time. However, little is known regarding the influence of ZA on marrow adipogenesis. The purpose of this study was to monitor the ability of early administration of ZA in restoring marrow adiposity in an estrogen-deficient rat model. Thirty female Sprague-Dawley rats were randomly divided into SHAM-operated, OVX + vehicle, and OVX + ZA groups (n=10/group). Dual-energy X-ray absorptiometry and water/fat MRI were performed at baseline, 6 weeks and 12 weeks after treatment to assess bone mineral density (BMD) and marrow fat fraction. Serum biochemical markers, bone remodeling and marrow adipocyte parameters were analyzed using biochemistry, histomorphometry and histopathology, respectively. The expression levels of osteoblast, adipocyte and osteoclast-related genes in bone marrow were assessed using RT-PCR. The OVX rats showed marked bone loss, first detected at 12 weeks, but estrogen deficiency resulted in a remarked increase in marrow fat fraction, first detected at 6 weeks compared with the SHAM rats (all P < 0.001). Similarly, the OVX rats had a substantially larger percent adipocyte area (+163.0%), mean diameter (+29.5%), and higher density (+57.3%) relative to the SHAM rats. Bone histomorphometry, levels of osteoclast-related gene expression and a serum resorption marker confirmed that ZA significantly suppressed bone resorption activities. Furthermore, ZA treatment returned adipocyte-related gene expression and marrow adipocyte parameters toward SHAM levels. These data suggest that a single dose of early ZA treatment acts to reverse marrow adipogenesis occurring during estrogen deficiency, which may contribute to its capacity to reduce bone loss.
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Tin Sulfide @Reduced Graphene Oxide Nanocomposite for High Efficiency Dye-Sensitized Solar Cells.
ACS Appl Mater Interfaces
PUBLISHED: 09-19-2014
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A nanocomposite of SnS2 nanoparticles with reduced graphene oxide (SnS2@RGO) had been successfully synthesized as a substitute conventional Pt counter electrode (CE) in dye-sensitized solar cell (DSSC) system. The SnS2 nanoparticles were uniformly dispersed onto graphene sheets, which formed a nano-sized composite system. The effectiveness of this nanocomposite exhibited remarkable electro-catalytic property on reducing the triiodide, owning to synergetic effect of SnS2 nanoparticles dispersed on graphene sheet and the improved conductivity. Consequently, the DSSC equipped with SnS2@RGO nanocomposite CE achieved a power conversion efficiency (PCE) of 7.12%, which was higher than those of use SnS2 nanoparticles (5.58%) or graphene sheet alone (3.73%) as CEs, and also comparable to 6.79% obtained with pure Pt CE for a reference.
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Overexpression of PSF1 is correlated with poor prognosis in hepatocellular carcinoma patients.
Int. J. Biol. Markers
PUBLISHED: 09-05-2014
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PSF1 is a subunit of the GINS complex which is essential for establishment of DNA replication forks, and the progression of the replisome. Previous studies have shown a close relationship between PSF1 and cell cycle in the proliferation of immature cells as well as tumors. The purpose of this study was to measure PSF1 expression in hepatocellular carcinoma (HCC) tissues, and determine the effects of down-regulation of PSF1 expression on growth of cancer cells, the cell cycle, apoptosis and cell invasiveness.
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Synthesis of phenanthrenes through copper-catalyzed cross-coupling of N-tosylhydrazones with terminal alkynes.
J. Org. Chem.
PUBLISHED: 09-03-2014
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A novel protocol for the synthesis of phenanthrenes through the copper-catalyzed reaction of aromatic tosylhydrazones with terminal alkynes is explored. The reaction proceeds via the formation of an allene intermediate and subsequent six-?-electron cyclization-isomerization, affording phenanthrene derivatives in good yields. The transformation can be performed in two ways: (1) with N-tosylhydrazones derived from [1,1'-biphenyl]-2-carbaldehydes and terminal alkynes as the starting materials and (2) with N-tosylhydrazones derived from aromatic aldehydes and 2-alkynyl biphenyls as the starting materials. This new phenanthrene synthesis uses readily available starting materials and a cheap copper catalyst and has a wide range of functional group compatibility.
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Nonstructural proteins 2C and 3D are involved in autophagy as induced by the encephalomyocarditis virus.
Virol. J.
PUBLISHED: 09-01-2014
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Encephalomyocarditis virus (EMCV) can infect a variety of animal species and humans. Although the EMCV infection is known to induce autophagy to promote its replication in host cells, the viral proteins that are responsible for inducing autophagy are unknown.
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Implementation and evaluation of the chronic-disease self-management program among Chinese immigrant older adults in the U.S.
Geriatr Nurs
PUBLISHED: 08-22-2014
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This article describes the implementation and evaluation of the chronic-disease self-management (CDSM) program, developed by Stanford University, among Chinese older adults in a metro area of a large Southeastern City of the U.S. The method of Practical Participatory Evaluation through an academic-community partnership between university researchers and local Chinese communities was used to develop the program and assess its applicability in the population. Results suggested that language proficiency, communication, social network and culture of the population were the most influential factors for U.S. Chinese immigrants to attend the CDSM program. The program increased participants' knowledge, skills and confidence in CDSM, whereas its capability in addressing culture differences needed improvement. Knowledge learned in this project was instrumental in implementing similar projects among immigrants.
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VdMsb regulates virulence and microsclerotia production in the fungal plant pathogen Verticillium dahliae.
Gene
PUBLISHED: 08-21-2014
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The vascular wilt fungus Verticillium dahliae infects the roots of cotton plants and can seriously diminish the yield and quality of this and other dicotyledons. However, the key genes involved in V. dahliae infection and pathogenesis in cotton remain unclear. Msb encodes a transmembrane mucin that is highly conserved in the MAPK signal pathway. Msb has been implicated previously in pathogenicity in various aerial plant fungi. In this study, V. dahliae Msb (VdMsb) was found to be required for fungal virulence and microsclerotia production. Strains lacking VdMsb exhibited reduced conidiation and microsclerotia formation. Compared with wild-type and gene-complemented strains, the invasive growth and adhesive capacity of VdMsb deletion mutants were significantly decreased. These results suggest that VdMsb plays a role in development and virulence in V. dahliae.
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The interaction of nonstructural protein 9 with retinoblastoma protein benefits the replication of genotype 2 porcine reproductive and respiratory syndrome virus in vitro.
Virology
PUBLISHED: 08-21-2014
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The nonstructural protein 9 (Nsp9) of porcine reproductive and respiratory syndrome virus (PRRSV) is a RNA-dependent RNA polymerase (RdRp) that plays a vital role in viral replication. This study first demonstrated that the Nsp9 of genotype 2 PRRSV interacted with cellular retinoblastoma protein (pRb), and Nsp9 co-localized with pRb in the cytoplasm of PRRSV-infected MARC-145 cells and pulmonary alveolar macrophages (PAMs). Next, the overexpression of truncated pRb was shown to inhibit the PRRSV replication and silencing the pRb gene could facilitate the PRRSV replication in MARC-145 cells. Finally, the pRb level was confirmed to be down-regulated in PRRSV-infected MARC-145 cells, and Nsp9 was shown to promote the pRb degradation by proteasome pathway. These findings indicate that the interaction of Nsp 9 with pRb benefits the replication of genotype 2 PRRSV in vitro, helping to understand the roles of Nsp9 in the replication and pathogenesis of PRRSV.
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Evaluation of up-converting phosphor technology-based lateral flow strips for rapid detection of Bacillus anthracis Spore, Brucella spp., and Yersinia pestis.
PLoS ONE
PUBLISHED: 08-21-2014
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Bacillus anthracis, Brucella spp., and Yersinia pestis are zoonotic pathogens and biowarfare- or bioterrorism-associated agents that must be detected rapidly on-site from various samples (e.g., viscera and powders). An up-converting phosphor technology-based lateral flow (UPT-LF) strip was developed as a point-of-care testing (POCT) to satisfy the requirements of first-level emergency response. We developed UPT-LF POCT to quantitatively detect the three pathogens within 15 min. Sample and operation-error tolerances of the assay were comprehensively evaluated. The sensitivity of UPT-LF assay to bacterial detection reached 10(4) cfu · mL(-1) (100 cfu/test), with a linear quantitative range of 4 to 6 orders of magnitude. Results revealed that the UPT-LF assay exhibited a high specificity with the absence of false-positive results even at 10(9) cfu · mL(-1) of non-specific bacterial contamination. The assay could tolerate samples with a wide pH range (2 to 12), high ion strengths (? 4 mol · L(-1) of NaCl), high viscosities (? 25 mg · mL(-1) of PEG20000 or ? 20% of glycerol), and high concentrations of bio-macromolecule (? 200 mg · mL(-1) of bovine serum albumin or ? 80 mg · mL(-1) of casein). The influence of various types of powders and viscera (fresh and decomposed) on the performance of UPT-LF assay was determined. The operational error of liquid measurement exhibited few effects on sensitivity and specificity. The developed UPT-LF POCT assay is applicable under field conditions with excellent tolerance to sample complexity and operational error.
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Comparison of the clinical and radiological outcomes following midvastus and medial parapatellar approaches for total knee arthroplasty: a meta-analysis.
Chin. Med. J.
PUBLISHED: 08-19-2014
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Controversy still exists regarding whether medial parapatellar approach (MP) or midvastus approach (MV) is preferable in total knee arthroplasty (TKA) up to now. The aim of this meta-analysis was to compare the clinical and radiological outcomes following the MV or MP for TKA.
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Melatonin attenuates hypoxic pulmonary hypertension by inhibiting the inflammation and the proliferation of pulmonary arterial smooth muscle cells.
J. Pineal Res.
PUBLISHED: 08-18-2014
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Hypoxia-induced inflammation and excessive proliferation of pulmonary artery smooth muscle cells (PASMCs) play important roles in the pathological process of hypoxic pulmonary hypertension (HPH). Melatonin possesses anti-inflammatory and antiproliferative properties. However, the effect of melatonin on HPH remains unclear. In this study, adult Sprague-Dawley rats were exposed to intermittent chronic hypoxia for 4 wk to mimic a severe HPH condition. Hemodynamic and pulmonary pathomorphology data showed that chronic hypoxia significantly increased right ventricular systolic pressures (RVSP), weight of the right ventricle/left ventricle plus septum (RV/LV+S) ratio, and median width of pulmonary arterioles. Melatonin attenuated the elevation of RVSP, RV/LV+S, and mitigated the pulmonary vascular structure remodeling. Melatonin also suppressed the hypoxia-induced high expression of proliferating cell nuclear antigen (PCNA), hypoxia-inducible factor-1? (HIF-1?), and nuclear factor-?B (NF-?B). In vitro, melatonin concentration-dependently inhibited the proliferation of PASMCs and the levels of phosphorylation of Akt and extracellular signal-regulated kinases1/2 (ERK1/2) caused by hypoxia. These results suggested that melatonin might potentially prevent HPH via anti-inflammatory and antiproliferative mechanisms.
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Effects of Denosumab, Alendronate, or Denosumab Following Alendronate on Bone Turnover, Calcium Homeostasis, Bone Mass and Bone Strength in Ovariectomized Cynomolgus Monkeys.
J. Bone Miner. Res.
PUBLISHED: 08-11-2014
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Postmenopausal osteoporosis is a chronic disease wherein increased bone remodeling reduces bone mass and bone strength. Antiresorptive agents including bisphosphonates are commonly used to mitigate bone loss and fracture risk. Osteoclast inhibition via denosumab (DMAb), a RANKL inhibitor, is a newer approach for reducing fracture risk in patients at increased risk for fracture. The safety of transitioning from bisphosphonate therapy (alendronate; ALN) to DMAb was examined in mature ovariectomized (OVX) cynomolgus monkeys (cynos). One day after OVX, cynos (7-10/group) were treated with vehicle (VEH, s.c.), ALN (50?µg/kg, i.v., twice monthly) or DMAb (25?mg/kg/month,?s.c.) for 12 months. Other animals received VEH or ALN for 6 months and then transitioned to 6 months of DMAb. DMAb caused significantly greater reductions in serum CTx than ALN, and transition from ALN to DMAb caused further reductions relative to continued ALN. DMAb and ALN decreased serum calcium (Ca), and transition from ALN to DMAb resulted in a lesser decline in Ca relative to DMAb or VEH-DMAb transition. Bone histomorphometry indicated significantly reduced trabecular and cortical remodeling with DMAb or ALN. Compared with ALN, DMAb caused greater reductions in osteoclast surface, eroded surface, cortical porosity and fluorochrome labeling, and transition from ALN to DMAb reduced these parameters relative to continued ALN. Bone mineral density increased in all active treatment groups relative to VEH controls. Destructive biomechanical testing revealed significantly greater vertebral strength in all three groups receiving DMAb, including those receiving DMAb after ALN, relative to VEH controls. Bone mass and strength remained highly correlated in all groups at all tested skeletal sites, consistent with normal bone quality. These data indicate that cynos transitioned from ALN to DMAb exhibited reduced bone resorption and cortical porosity, and increased BMD and bone strength, without deleterious effects on Ca homeostasis or bone quality. © 2014 American Society for Bone and Mineral Research.
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Bcl-2 family proteins are involved in the signal crosstalk between endoplasmic reticulum stress and mitochondrial dysfunction in tumor chemotherapy resistance.
Biomed Res Int
PUBLISHED: 08-10-2014
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Tumor cells overexpress antiapoptotic proteins of the Bcl-2 (B-cell leukemia/lymphoma-2) family, which can lead to both escape from cell death and resistance to chemotherapeutic drugs. Recent studies suggest that the endoplasmic reticulum (ER) can produce proapoptotic signals, amplifying the apoptotic signaling cascade. The crosstalk between mitochondria and ER plays a decisive role in many cellular events but especially in cell death. Bcl-2 family proteins located in the ER and mitochondria can influence not only the function of the two organelles but also the interaction between them. Therefore, the Bcl-2 family of proteins may also be involved in the mechanism of tumor chemotherapy resistance by influencing crosstalk between the ER and mitochondria. In this review we will briefly discuss evidence to support this concept.
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Highly biocompatible zwitterionic phospholipids coated upconversion nanoparticles for efficient bioimaging.
Anal. Chem.
PUBLISHED: 08-07-2014
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The potential of upconversion nanoparticles (UCNPs) in various biomedical applications, including immunoassays, biomedical imaging, and molecular sensing, requires their surface derivatized to be hydrophilic and biocompatible. Here, a new family of compact zwitterionic ligand systems composed with functional phospholipids was designed and used for the surface modification of UCNPs. The zwitterionic UCNPs are hydrophilic, compact, and easily functionalized. It was proved that zwitterionic phospholipids could provide UCNPs with not only extended pH and salt stability but also little nonspecific interactions to positively and negatively charged proteins, low nonspecific adhesion in live-cell imaging process. Most notably, the efficient in vivo tumor imaging performance and long blood circulation half-life suggests the excellent biocompatibility for in vivo imaging of the zwitterionic UCNPs.
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Porcine reproductive and respiratory syndrome virus counteracts the porcine intrinsic virus restriction factors-IFITM1 and Tetherin in MARC-145 cells.
Virus Res.
PUBLISHED: 08-04-2014
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Porcine reproductive and respiratory syndrome virus (PRRSV) has been recognized to modulate the innate immune response of host. However, little is known about the effects of PRRSV infection on porcine intrinsic virus-restriction factors. This study presents the first demonstration that the nonstructural protein 3 (Nsp3) or envelope (E) protein of PRRSV interacted with porcine intrinsic virus-restriction factor IFITM1 or Tetherin. Next, in PRRSV-infected MARC-145 cells and the transfected cells with the IFITM1- or Tetherin-expressing plasmid, IFITM1 was shown to be mainly distributed perinuclear, and Tetherin was proposed to be partially removed away from cell surface. Moreover, the overexpression of IFITM1 and Tetherin were shown to have no obvious effects on the replication of PRRSV in MARC-145 cells. The Nsp3 of PRRSV was demonstrated to induce the proteasome-dependent degradation of IFITM1 upon PRRSV infection. These findings suggest that PRRSV might counteract the antiviral functions of IFITM1 and Tetherin by the interaction of the Nsp3 with IFITM1 and the E protein with Tetherin, providing a novel clue for exploring possible mechanisms associated with the evasion of PRRSV from immune recognition of host.
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Metal-free visible-light induced cross-dehydrogenative coupling of tertiary amines with diazo compounds.
Org. Lett.
PUBLISHED: 07-30-2014
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The first visible-light induced cross-dehydrogenative coupling between tertiary amines and diazo compounds is described. The reaction proceeds smoothly under mild and metal-free conditions by using air or O2 as the oxidant, affording various ?-amino-?-diazo adducts in moderate to good yields with broad substrate scopes. The resulting products were successfully employed for the synthesis of 4- or 5-ester N-aryl-2,3-dihydrobenzo[d]azepines with high regioselectivity simply switched by the selection of the transition metal catalysts.
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Epitaxial Seeded Growth of Rare-Earth Nanocrystals with Efficient 800?nm Near-Infrared to 1525?nm Short-Wavelength Infrared Downconversion Photoluminescence for In?Vivo Bioimaging.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 07-21-2014
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Novel ?-NaGdF4 /Na(Gd,Yb)F4 :Er/NaYF4 :Yb/NaNdF4 :Yb core/shell?1/shell?2/shell?3 (C/S1/S2/S3) multi-shell nanocrystals (NCs) have been synthesized and used as probes for in?vivo imaging. They can be excited by near-infrared (800?nm) radiation and emit short-wavelength infrared (SWIR, 1525?nm) radiation. Excitation at 800?nm falls into the "biological transparency window", which features low absorption by water and low heat generation and is considered to be the ideal excitation wavelength with the least impact on biological tissues. After coating with phospholipids, the water-soluble NCs showed good biocompatibility and low toxicity. With efficient SWIR emission at 1525?nm, the probe is detectable in tissues at depths of up to 18?mm with a low detection threshold concentration (5?nM for the stomach of nude mice and 100?nM for the stomach of SD rats). These results highlight the potential of the probe for the in?vivo monitoring of areas that are otherwise difficult to analyze.
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Differential regulation of orphan nuclear receptor TR3 transcript variants by novel vascular growth factor signaling pathways.
FASEB J.
PUBLISHED: 07-11-2014
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Angiogenesis is a hallmark of many diseases, including cancer, ischemic heart disease, inflammation, and others. It is well known that vascular endothelial growth factor (VEGF) is the most important angiogenic factor. Recently, we demonstrated that orphan nuclear receptor TR3 (mouse Nur77 and rat NGFI-B) plays critical roles in tumor growth and angiogenesis induced by VEGF-A in vitro and in vivo. However, the signaling pathways that mediate the expression of TR3 induced by VEGF are still not completely understood. Here we reported that 3 TR3 transcript variants (TR3-TVs) are expressed at differential levels, and regulated differentially in endothelial cells. While the expression of TR3-TV1 is relatively low, the expression of TR3-TV2 is up-regulated markedly, and the expression of TR3-TV3 is up-regulated moderately in endothelial cells induced by VEGF-A. The kinetics of the induction of these TR3-TVs is different. We also found that several signaling pathways, including calcium-PLC-PKC-PKD1 pathway, NF-?B pathway, and MAP kinase (ERK, p38, and JNK) pathways are important for VEGF-A-induced TR3-TV2 and TR3-TV3 mRNA induction. More important, we found that VEGF-A or VEGF-E, but not VEGF-B, nor placenta growth factor (PlGF), induces the phosphorylation of insulin-like growth factor-1 receptor (IGF-1R) and the interaction of VEGF receptor 2/kinase insert domain receptor (VEGFR2/KDR) with IGF-1R, which mediates the expression of TR3-TV2, but not TR3-TV3. Taking together, we demonstrate that TR3-TVs are differentially regulated by VEGF-A and identify a novel signaling pathway by which VEGF-A and VEGF-E, but neither VEGF-B, nor PlGF, induce the interaction of VEGFR2/KDR with IGF-1R, resulting in IGF-1R transactivation to induce the high level expression of TR3-TV2. Our data not only elucidate the signaling pathways by which TR3-TVs are regulated, but extend the molecular mechanism, by which VEGF-A-induced angiogenesis. These studies should permit the development of screening assays for compounds that inhibit VEGF signaling.
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CuI-catalyzed cross-coupling of terminal alkynes with dialkoxycarbenes: a general method for the synthesis of unsymmetrical propargylic acetals.
Org. Biomol. Chem.
PUBLISHED: 07-11-2014
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A general source of dialkoxycarbenes, 2,2-dialkoxy-5,5-dimethyl-?(3)-1,3,4-oxadiazolines, have been successfully employed as coupling partners in CuI-catalyzed cross-coupling reactions with terminal alkynes, which afforded various unsymmetrical propargylic acetals in good yields.
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[Heparin-binding hemagglutinin enhances Mycobacterium smegmatis infection by inhibiting autophagy in A549 cells].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 07-09-2014
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To construct recombinant Mycobacterium smegmatis (MS) expressing heparin-binding hemagglutinin (HBHA) (rMS-HBHA) and identify its impact on autophagy in the A549 cells.
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Inhibition of CRAC with a human anti-ORAI1 monoclonal antibody inhibits T-cell-derived cytokine production but fails to inhibit a T-cell-dependent antibody response in the cynomolgus monkey.
J Immunotoxicol
PUBLISHED: 07-04-2014
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Abstract ORAI1 is the pore-forming component of calcium release-activated calcium (CRAC) channels. CRAC channels are the primary route for calcium ion (Ca(2+)) entry into T-cells following antigen stimulation. This Ca(2+) entry induces proliferation and cytokine production through activation of calcineurin and the nuclear factor of activated T-cells (NFAT) transcription factor along with subsequent cytokine-related genes. It was hypothesized that the in vivo inhibition of T-cell function by blocking ORAI1 or calcineurin would lead to similar functional consequences. To test this hypothesis the activity of 2C1.1, a fully human anti-ORAI1 monoclonal antibody, and cyclosporin A (CsA) were tested in vivo for their suppressive effect on T-cell-derived cytokine production and a T-cell-dependent antibody response (TDAR) using sheep red blood cells (SRBC) in cynomolgus monkeys. Despite showing similar inhibition of ex vivo interleukin (IL)-2 production by stimulated T-cells, both molecules exhibited different pharmacologic effects on the SRBC antibody response. CsA blocked the development of SRBC-specific antibodies, while 2C1.1 failed to inhibit the antigen-specific antibody response. These surprising observations suggest that full inhibition of the CRAC channel is required to inhibit a functional immune response, consistent with findings from human patients with loss of function mutations in ORAI1.
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Nsp9 and Nsp10 contribute to the fatal virulence of highly pathogenic porcine reproductive and respiratory syndrome virus emerging in China.
PLoS Pathog.
PUBLISHED: 07-01-2014
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Atypical porcine reproductive and respiratory syndrome (PRRS), which is caused by the Chinese highly pathogenic PRRS virus (HP-PRRSV), has resulted in large economic loss to the swine industry since its outbreak in 2006. However, to date, the region(s) within the viral genome that are related to the fatal virulence of HP-PRRSV remain unknown. In the present study, we generated a series of full-length infectious cDNA clones with swapped coding regions between the highly pathogenic RvJXwn and low pathogenic RvHB-1/3.9. Next, the in vitro and in vivo replication and pathogenicity for piglets of the rescued chimeric viruses were systematically analyzed and compared with their backbone viruses. First, we swapped the regions including the 5'UTR+ORF1a, ORF1b, and structural proteins (SPs)-coding region between the two viruses and demonstrated that the nonstructural protein-coding region, ORF1b, is directly related to the fatal virulence and increased replication efficiency of HP-PRRSV both in vitro and in vivo. Furthermore, we substituted the nonstructural protein (Nsp) 9-, Nsp10-, Nsp11- and Nsp12-coding regions separately; or Nsp9- and Nsp10-coding regions together; or Nsp9-, Nsp10- and Nsp11-coding regions simultaneously between the two viruses. Our results indicated that the HP-PRRSV Nsp9- and Nsp10-coding regions together are closely related to the replication efficiency in vitro and in vivo and are related to the increased pathogenicity and fatal virulence for piglets. Our findings suggest that Nsp9 and Nsp10 together contribute to the fatal virulence of HP-PRRSV emerging in China, helping to elucidate the pathogenesis of this virus.
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Solid state molecular dynamic investigation of an inclusion ferroelectric: [(2,6-diisopropylanilinium)([18]crown-6)]BF?.
J. Am. Chem. Soc.
PUBLISHED: 06-30-2014
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Many order-disorder-type phase transitions in molecule-based ferroelectrics are related to changes of molecular dynamics. If the molecular motions do not involve reorientations of dipole moments, their ordering fails to contribute directly to spontaneous electric polarization. For understanding ferroelectric mechanisms in these systems, it is important to clarify how such molecular dynamics changes induce structurally symmetry-breaking phase transitions and thus the appearance of spontaneous electric polarization. Systematic characterization of an [18]crown-6 based host-guest inclusion compound, [(DIPA)([18]crown-6)]BF4 (DIPA = 2,6-diisopropylanilinium), shows it is an excellent ferroelectric with a large dielectric anomaly, significant pyroelectricity, and SHG response, and rectangular polarizaiton-electric field hysterisis loops. By the combination of variable-temperature single-crystal structural determination and solid-state NMR observation, it is found that the slowing down of the rotation of the [18]crown-6 molecule and the tumbling of the BF4 anion causes the symmetry breaking, while the spontaneous polarization is induced by the relative displacement between the cationic and anionic sublattices. This investigation will contribute to a deeper understanding of the structure-property relationship in the emerging molecular ferroelectrics.
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[The influence of ultraviolet irradiation on sandblasted and acid-etching surface adsorbing human fibronectin].
Zhonghua Kou Qiang Yi Xue Za Zhi
PUBLISHED: 06-28-2014
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To study the influence of ultraviolet (UV) irradiation on physical and chemical properties of sandblasted and acid-etched (SA) titanium surface and their ability to adsorb human fibronectin (HFn).
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Simultaneous analysis of polychlorinated biphenyls and organochlorine pesticides in seawater samples by membrane-assisted solvent extraction combined with gas chromatography-electron capture detector and gas chromatography-tandem mass spectrometry.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 06-20-2014
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A highly efficient and environment-friendly membrane-assisted solvent extraction system combined with gas chromatography-electron capture detector was applied in the simultaneous determination of 17 polychlorinated biphenyls and organochlorine pesticides in seawater samples. Variables affecting extraction efficiency, including extraction solvent used, stirring rate, extraction time, and temperature, were optimized extensively. Under optimal extraction conditions, recoveries between 76.9% and 104.6% in seawater samples were achieved, and relative standard deviation values below 10% were obtained. The limit of detection (signal-to-noise ratio=3) and limit of quantification (signal-to-noise ratio=10) of 17 polychlorinated biphenyls and organochlorine pesticides in seawater ranged from 0.14ngL(-1) to 0.36ngL(-1) and 0.46ngL(-1) to 1.19ngL(-1), respectively. Matrix effects on extraction efficiency were evaluated by comparing with the results obtained using tap water. The extraction effect of developed membrane-assisted solvent extraction method was further demonstrated by gas chromatography-tandem mass spectrometry which can provide structural information of the analytes for more accurate identification, and results identical to those produced by gas chromatography-electron capture detector were obtained. These findings demonstrate the applicability of the developed membrane-assisted solvent extraction determination method for coupling to gas chromatography-electron capture detector or tandem mass spectrometry for determining polychlorinated biphenyls and organochlorine pesticides in seawater samples.
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A rapid method for simultaneous determination of 52 marker compounds in Xiao-Qing-Long-Tang by ultra high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry†.
J Sep Sci
PUBLISHED: 06-18-2014
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Xiao-Qing-Long-Tang (XQLT) is a classical Chinese medicine formula. It is generally used for the treatment of common cold, bronchial asthma, and allergic rhinitis in Asia. In this study, a multicomponent quantification fingerprinting approach based on ultra high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry has been developed for the analysis of compounds in XQLT in 14.5 min. A total of 52 compounds were identified by co-chromatography of sample extract with authentic standards and comparing the retention time, UV spectra, molecular ions and characteristic fragment ions with those of authentic standards, or tentatively identified by MS(E) determination along with Mass Fragment software. Moreover, the method was validated for the simultaneous quantification of 16 components in XQLT commercial products. The method is practical for comprehensive standardization of XQLT and holistic comparison of its commercial products from different manufacturers.
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Risk factors for influenza A(H7N9) disease--China, 2013.
Clin. Infect. Dis.
PUBLISHED: 06-13-2014
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The majority of human cases of novel avian influenza A(H7N9), which emerged in China in spring 2013, include reported exposure to poultry. However, specific host and exposure risk factors for disease are unknown, yet critical to design prevention measures.
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Synthesis of 3-acylindoles by visible-light induced intramolecular oxidative cyclization of o-alkynylated N,N-dialkylamines.
Org. Lett.
PUBLISHED: 06-04-2014
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A visible-light photoredox synthesis of 3-acylindoles through intramolecular oxidative cyclization of o-alkynylated N,N-dialkylamines is developed. The reaction proceeds effectively under mild reaction conditions using air as the oxidant, and only water is generated as a side product. A plausible mechanism involving the addition of ?-amino alkyl radicals to alkynes, followed by C-O bond formation, is proposed.
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A C-terminal truncated mutation of licC attenuates the virulence of Streptococcus pneumoniae.
Res. Microbiol.
PUBLISHED: 05-15-2014
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LicC has been identified as a virulence factor of Streptococcus pneumoniae. However, its role in virulence is still not fully understood because deletion of licC is lethal for the bacterium. In this study, a mutant with 78-bp truncation at the C-terminus of licC was obtained from a signature-tagged mutagenesis (STM) library. The mutant was viable with a large reduction in enzymatic activity as CTP:phosphocholine cytidylyltransferase detected in vitro using a firefly luciferase assay. The mutation attenuated the adhesion and invasion of S. pneumoniae ST556 (serotype 19F) to epithelial cells by 72% and 80%, respectively, and increased the phagocytosis by macrophages for 16.5%, compared to the parental strain. When the mutation was introduced into the encapsulated D39 strain (serotype 2), it led to attenuated virulence in mouse models either by intranasal colonization or by intraperitoneal infection. In addition, the phosphocholine (PCho) on cell surface was decreased, and the choline binding proteins (CBPs) were impaired, which may explain the attenuated virulence of the mutant. These observations indicate that C-terminus of licC is accounted for the main activity of LicC in PCho metabolism and is essential for the virulence of S. pneumoniae, which provides a novel target for drug design against pneumococcal infection.
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Genomic organization and molecular characterization of porcine cytomegalovirus.
Virology
PUBLISHED: 05-07-2014
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A strain of the porcine cytomegalovirus (PCMV), which causes inclusion body rhinitis in newborn piglets, has been characterized with respect to its complete genome sequence. The virus genome is 128,367bp, containing 79 predicted open reading frames (ORFs). Of these ORFs, 69 have counterparts in human herpesvirus 6A (HHV-6A), 6B (HHV-6B) and 7 (HHV-7), and two ORFs are homologous to other members in the subfamily Betaherpesvirinae. Eight ORFs have no homologs in herpesvirus. Homologs had higher identity and possessed similar orientation and location as roseoloviruses. The PCMV genome is a DR-U-DR type, similar to HHV-6A, HHV-6B and HHV-7, but the PCMV DR is shorter and lacks predicted genes and telomere-like sequences. Phylogenetic analyses of several core genes indicate that PCMV could be clustered in a branch with roseoloviruses. We suggest that PCMV could be classified as a member of the genus Roseolovirus of the subfamily Betaherpesvirinae.
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Translocation of CIDEC in hepatocytes depends on fatty acids.
Genes Cells
PUBLISHED: 04-27-2014
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The CIDEC protein is located in lipid droplets (LDs) and the endoplasmic reticulum (ER) and is induced in fat deposition. However, the binding domain, the functional domain and the underlying mechanism of CIDEC in stimulating lipid accumulation remain unclear. Here, we investigated the subcellular localization and function of pig CIDEC and confirmed CIDEC promotes unilocular development of LDs, reduces the specific surface area (SSA) of LDs and stimulates lipid accumulation in HepG2 cells. By analyzing a series of CIDEC mutants, we showed the N-domain (1-173 amino acid) is involved in LD localization and the C-domain (174-238 amino acid) is necessary for LD fusion. Further analysis indicated that the 106-173 amino acid region includes an ER-binding domain. Moreover, CIDEC stayed in the ER under lipid-deficient conditions and translocated to LDs under fatty acid stimulation suggesting that localization of CIDEC in the ER is before the LD. Our data indicated additional fatty acids stimulated hepatic CIDEC expression and an increasing level of CIDEC induced hepatic LD fusion and lipid accumulation. Our work suggests that CIDEC protects LDs by decreasing the SSA of LDs and is involved in the regulation of hepatic lipid deposition.
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Cell-laden photocrosslinked GelMA-DexMA copolymer hydrogels with tunable mechanical properties for tissue engineering.
J Mater Sci Mater Med
PUBLISHED: 04-25-2014
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To effectively repair or replace damaged tissues, it is necessary to design three dimensional (3D) extracellular matrix (ECM) mimicking scaffolds with tunable biomechanical properties close to the desired tissue application. In the present work, gelatin methacrylate (GelMA) and dextran glycidyl methacrylate (DexMA) with tunable mechanical and biological properties were utilized to prepared novel bicomponent polymeric hydrogels by cross-linking polymerization using photoinitiation. We controlled the degree of substitution (DS) of glycidyl methacrylate in DexMA so that they could obtain relevant mechanical properties. The results indicated that copolymer hydrogels demonstrated a lower swelling ratio and higher compressive modulus as compared to the GelMA. Moreover, all of the hydrogels exhibited a honeycomb-like architecture, the pore sizes decreased as DS increased, and NIH-3T3 fibroblasts encapsulated in these hydrogels all exhibited excellent viability. These characteristics suggest a class of photocrosslinkable, tunable mechanically copolymer hydrogels that may find potential application in tissue engineering and regenerative medicine applications.
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Combination of percutaneous radiofrequency ablation with transarterial chemoembolization for hepatocellular carcinoma: observation of clinical effects.
Chin. J. Cancer Res.
PUBLISHED: 04-02-2014
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To observe the clinical effect of radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) for advanced hepatocellular carcinoma (HCC).
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Functional selectivity of GPCR signaling in animals.
Curr. Opin. Cell Biol.
PUBLISHED: 04-01-2014
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At one time, G protein-coupled receptors were envisioned to simply relay either inhibitory or stimulatory binary signals through engaging particular G proteins. These receptors are now viewed as complex, multidimensional triggers of a variety of potential signaling cascades. This review will showcase current attempts to elucidate biased signaling and functional selectivity in tissues and organs as well as in the whole animal. In addition, it will emphasize the challenges that are inherent in attributing bias in a living system as well as offer opinions as to the manner in which these problems may be approached.
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The amino acid at residue 155 in nonstructural protein 4 of porcine reproductive and respiratory syndrome virus contributes to its inhibitory effect for interferon-? transcription in vitro.
Virus Res.
PUBLISHED: 02-25-2014
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Type I interferons (IFNs), predominantly IFN-? and ?, play important roles in both innate and adaptive immune responses against viral infections. Porcine reproductive and respiratory syndrome virus (PRRSV) has been recognized to be able to down-regulate the IFN response during in vivo and in vitro infection. In this study, we first analyzed inhibitory effect of each NSP of low pathogenic PRRSV HB-1/3.9 on IFN-? transcription in MARC-145 cells, and the results showed that the IFN-? promoter activation could be suppressed by NSP1?, NSP2, NSP1?, NSP3, NSP4, NSP5 and NSP11. We next confirmed that the inhibitory effect of NSP4 was mainly mediated through suppressing NF-?B activation, whereas not hindering NF-?B phosphorylation and nuclear translocation, and nuclear-localized NSP4 was responsible for inhibiting IFN-? activation. We further found that the NSP4 of different pathogenic PRRSV strains exhibited differential inhibitory effect on IFN-?, NF-?B, and IRF3 transcription, and the NSP4 of highly pathogenic (HP)-PRRSV could display more strong inhibitory effect. Finally, we determined that the amino acid at residue 155 in NSP4 contributed to its inhibitory effect for IFN-? transcription in vitro by altering its subcellular distribution. Our findings suggest that the nucleus-localized NSP4 of PRRSV participates in the modulation of the host type I IFNs system, and also provide novel insight for understanding the pathogenesis of the Chinese HP-PRRSV.
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Computer-aided codon-pairs deoptimization of the major envelope GP5 gene attenuates porcine reproductive and respiratory syndrome virus.
Virology
PUBLISHED: 02-08-2014
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Synthetic attenuated virus engineering (SAVE) is an emerging technology that enables rapid attenuation of viruses. In this study, by using SAVE we demonstrated rapid attenuation of an arterivirus, porcine reproductive and respiratory syndrome virus (PRRSV). The major envelope GP5 gene of PRRSV was codon-pair deoptimized aided by a computer algorithm. The codon-pair deoptimized virus, designated as SAVE5 with a deoptimized GP5 gene, was successfully rescued in vitro. The SAVE5 virus replicated at a lower level in vitro with a significant decrease of GP5 protein expression compared to the wild-type PRRSV VR2385 virus. Pigs experimentally infected with the SAVE5 virus had significantly lower viremia level up to 14 days post-infection as well as significantly reduced gross and histological lung lesions when compared to wild-type PRRSV VR2385 virus-infected pigs, indicating the attenuation of the SAVE5 virus. This study proved the feasibility of rapidly attenuating PRRSV by SAVE.
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Severe sepsis: Low expression of the renin-angiotensin system is associated with poor prognosis.
Exp Ther Med
PUBLISHED: 01-24-2014
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Severe sepsis has a high fatality rate, but no clinical indices for prognosis have been established. In recent years, the renin-angiotensin system (RAS) has received considerable attention. However, clinical data on RAS are inconsistent. Therefore, the aim of the present study was to assess the significance of RAS in the prognosis of sepsis. Blood samples were collected from patients, who met the diagnostic criteria of severe sepsis, on day 1 (D1) and 3 (D3). For each sample, the levels of angiotensin II (AngII), angiotensin-converting enzyme (ACE) and additional indices were measured. Patients were monitored for 28 days. On the D1 of inclusion, the average Acute Physiology and Chronic Health Evaluation II (APACHE II) score was 22.2 and the Sepsis-related Organ Failure Assessment (SOFA) score was 6.1. Logistic regression analysis revealed that mortality-associated variables included the APACHE II score on D1, the SOFA score on D1, high lactic acid levels on D3 and low AngII and ACE levels on D1 and D3. AngII levels (<86.1 ng/ml) on D1 had a sensitivity of 88.2% and specificity of 77.3% for predicting mortality. ACE levels (<39.2 ng/ml) on D1 had a sensitivity of 88.2% and specificity of 72.7% for predicting mortality. These two indices were better than the APACHE II and SOFA scores. Therefore, low expression levels of AngII and ACE are valuable in predicting the mortality of patients with severe sepsis.
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Massive and painful ascites as a presenting manifestation of systemic lupus erythematosus flare: a case report and literature review.
Rev Med Chil
PUBLISHED: 01-20-2014
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Lupus peritonitis (LP) is extremely rare. Acute LP is characterized by rapid onset of ascites and severe abdominal pain, in addition to other well-recognized clinical features of a general systemic lupus erythematosus (SLE) fare. Ascites associated with acute LP has been rarely reported as the prominent feature of a SLE fare. We report a 39-year-old woman who developed massive, painful ascites as the presenting manifestation of a SLE fare. Diagnostic workup ruled out the possibility of hepatic, cardiovascular, infectious, or malignant diseases, and confirmed the presence of a SLE fare. The patient was treated with methyl prednisolone and hydroxychloroquine resulting in dramatic improvement of her condition. During ambulatory follow up, she has remained asymptomatic up to the moment of this writing. Adrenal steroids and hydrocychloroquine may be useful for the management of SLE fares in patients with massive, painful ascites due to acute LP.
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Gut microbe analysis between hyperthyroid and healthy individuals.
Curr. Microbiol.
PUBLISHED: 01-07-2014
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Clinicians have long recognized that thyroid hormones have some effects on the gastrointestinal tract. This study aimed to investigate the gut microbiota in hyperthyroid and assess whether there are alterations in the diversity and similarity of gut microbiota in the hyperthyroid when compared with healthy individuals. PCR-denaturing gradient gel electrophoresis (DGGE) with universal primers targeting V3 region of the 16S rRNA gene was employed to characterize the overall intestinal microbiota composition, and some excised gel bands were cloned for sequencing. Enterobacteriaceae, Enterococcus, Bifidobacterium, Clostridium, and Lactobacillus genus were also enumerated by quantitative real-time PCR. A significant difference between hyperthyroid and healthy groups ((*) P < 0.05) was shown in DGGE profiles. And real-time PCR showed obvious decrease of Bifidobacterium and Lactobacillus ((*) P < 0.05), and increase of Enterococcus ((*) P < 0.05) in the hyperthyroid group. This study shows the characterization of gut microbiota in hyperthyroid.
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Impacts of Diffuse Radiation on Light Use Efficiency across Terrestrial Ecosystems Based on Eddy Covariance Observation in China.
PLoS ONE
PUBLISHED: 01-01-2014
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Ecosystem light use efficiency (LUE) is a key factor of production models for gross primary production (GPP) predictions. Previous studies revealed that ecosystem LUE could be significantly enhanced by an increase on diffuse radiation. Under large spatial heterogeneity and increasing annual diffuse radiation in China, eddy covariance flux data at 6 sites across different ecosystems from 2003 to 2007 were used to investigate the impacts of diffuse radiation indicated by the cloudiness index (CI) on ecosystem LUE in grassland and forest ecosystems. Our results showed that the ecosystem LUE at the six sites was significantly correlated with the cloudiness variation (0.24?R2?0.85), especially at the Changbaishan temperate forest ecosystem (R2?=?0.85). Meanwhile, the CI values appeared more frequently between 0.8 and 1.0 in two subtropical forest ecosystems (Qianyanzhou and Dinghushan) and were much larger than those in temperate ecosystems. Besides, cloudiness thresholds which were favorable for enhancing ecosystem carbon sequestration existed at the three forest sites, respectively. Our research confirmed that the ecosystem LUE at the six sites in China was positively responsive to the diffuse radiation, and the cloudiness index could be used as an environmental regulator for LUE modeling in regional GPP prediction.
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Interactome profile of the host cellular proteins and the nonstructural protein 2 of porcine reproductive and respiratory syndrome virus.
PLoS ONE
PUBLISHED: 01-01-2014
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The nonstructural protein 2 (NSP2) is considered to be one of crucial viral proteins in the replication and pathogenesis of porcine reproductive and respiratory syndrome virus (PRRSV). In the present study, the host cellular proteins that interact with the NSP2 of PRRSV were immunoprecipitated with anti-Myc antibody from the MARC-145 cells infected by a recombinant PRRSV with 3xMyc tag insertion in its NSP2-coding region, and then 285 cellular proteins interacting with NSP2 were identified by LC-MS/MS. The Gene Ontology and enriched KEGG Pathway bioinformatics analyses indicated that the identified proteins could be assigned to different subcellular locations and functional classes. Functional analysis of the interactome profile highlighted cellular pathways associated with infectious disease, translation, immune system, nervous system and signal transduction. Two interested cellular proteins-BCL2-associated athanogene 6 (BAG6) and apoptosis-inducing factor 1 (AIF1) which may involve in transporting of NSP2 to Endoplasmic reticulum (ER) or PRRSV-driven apoptosis were validated by Western blot. The interactome data between PRRSV NSP2 and cellular proteins contribute to the understanding of the roles of NSP2 in the replication and pathogenesis of PRRSV, and also provide novel cellular target proteins for elucidating the associated molecular mechanisms of the interaction of host cellular proteins with viral proteins in regulating the viral replication.
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High-efficiency broadband meta-hologram with polarization-controlled dual images.
Nano Lett.
PUBLISHED: 12-18-2013
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Holograms - the optical devices to reconstruct pre-designed images - show many applications in our daily life. However, applications of hologram are still limited by the constituent materials, and therefore their working range is trapped at a particular electromagnetic region. In recent years, the metasurfaces, an array of sub-wavelength antenna with varying sizes, show the abilities to manipulate the phase of incident electromagnetic wave from visible to microwave frequencies. Here, we present a reflective-type and high-efficiency meta-hologram fabricated by metasurface for visible wavelength. Using gold cross nano-antennas as building blocks to construct our meta-hologram devices with thickness ~ ?/4, the reconstructed images of meta-hologram show polarization-controlled dual images with high contrast, functioning for both coherent and incoherent light sources within a broad spectral range and under a wide range of incidence angles. The flexibility demonstrated here for our meta-hologram paves the road to a wide range of applications related to holographic images at arbitrary electromagnetic wave region.
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Behavior of acid etching on titanium: topography, hydrophility and hydrogen concentration.
Biomed Mater
PUBLISHED: 12-16-2013
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Since acid etching is easily controlled and effective, it has become one of the most common methods of surface modification. However, the behavior of etching is seldom discussed. In this study, different surfaces of titanium were prepared by changing the etching temperature and time. Surface topography, roughness, contact angles, surface crystalline structure, hydrogen concentration and mechanical properties were observed. As a result, surface topography and roughness were more proportional to etching temperature; however, diffusion of hydrogen and tensile strength are more time-related to titanium hydride formation on the surface. Titanium becomes more hydrophilic after etching even though the micropits were not formed after etching. More and deeper cracks were found on the specimens with more hydrogen diffusion. Therefore, higher temperature and shorter time are an effective way to get a uniform surface and decrease the diffusion of hydrogen to prevent hydrogen embrittlement.
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IL-17A Produced by Neutrophils Protects against Pneumonic Plague through Orchestrating IFN-?-Activated Macrophage Programming.
J. Immunol.
PUBLISHED: 12-13-2013
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Innate immune cells, including neutrophils and macrophages, are critically involved in host antimicrobial defense responses. Intrinsic regulatory mechanisms controlling neutrophil and macrophage activities are poorly defined. In this study, we found that IL-17A, a natural signal factor, could provide protection against early pneumonic plague inflammation by coordinating the functions of neutrophils and programming of macrophages. The IL-17A level is promptly increased during the initial infection. Importantly, abrogation of IL-17A or IL-17AR significantly aggravated the infection, but mIL-17A treatment could significantly alleviate inflammatory injury, revealing that IL-17A is a critical requirement for early protection of infection. We also demonstrated that IL-17A was predominantly produced by CD11b(+)Ly6G(+) neutrophils. Although IL-17A could not significantly affect the antimicrobial responses of neutrophils, it could target the proinflammatory macrophage (M1) programming and potentiate the M1s defense against pneumonic plague. Mechanistically, IFN-? treatment or IFN-?-activated M1 macrophage transfer could significantly mitigate the aggravated infection of IL-17A(-/-) mice. Finally, we showed that IL-17A and IFN-? could synergistically promote macrophage anti-infection immunity. Thus, our findings identify a previously unrecognized function of IL-17A as an intrinsic regulator in coordinating neutrophil and macrophage antimicrobial activity to provide protection against acute pneumonic plague.
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Dihydroartemisinin induces apoptosis of cervical cancer cells via upregulation of RKIP and downregulation of bcl-2.
Cancer Biol. Ther.
PUBLISHED: 12-11-2013
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Treatment of recurrent and metastatic cervical cancer remains a challenge, especially in developing countries, which lack efficient screening programs. In recent years, artemisinin and its derivatives, such as dihydroartemisinin (DHA), which were traditionally used as anti-malarial agent, have been shown to inhibit tumor growth with low toxicity to normal cells. In this study, we investigated mechanisms underlying the anti-tumor effect of DHA in cervical cancer. We evaluated the role of DHA on the expression of bcl-2 and Raf kinase inhibitor protein (RKIP), which is a suppressor of metastasis. The MTT assay was used to compare the proliferation of untreated and DHA-treated Hela and Caski cervical cancer cells. Flow cytometry was used to determine the percentage of cells at each stage of the cell cycle in untreated and DHA-treated cells. We used RT-PCR and western blots to determine the expression of bcl-2 and RKIP mRNA and proteins. We evaluated the effect of DHA treatment in nude mice bearing Hela or Caski tumors. DHA-treated cells showed a time- and dose-dependent inhibition of proliferation and a significant increase in apoptosis. The expression of RKIP was significantly upregulated and the expression of bcl-2 was significantly downregulated in DHA-treated cells compared with control cells. DHA treatment caused (1) a significant inhibition of tumor growth and (2) a significant increase in the apoptotic index in nude mice bearing Hela or Caski tumors. Our data suggest that DHA inhibits cervical cancer growth via upregulation of RKIP and downregulation of bcl-2.
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[Expressions of CD133 and CD44 in gastric adenocarcinoma and their relationship with E-cadherin expression].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 11-26-2013
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To explore the expression of CD133 and CD44 in the primary gastric adenocarcinoma (GAC) and their relationship with the expression of E-cadherin.
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hSETD1A regulates Wnt target genes and controls tumor growth of colorectal cancer cells.
Cancer Res.
PUBLISHED: 11-18-2013
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hSETD1A is a member of the trithorax (TrxG) family of histone methyltransferases (HMTs) that methylate H3K4 at promoters of active genes. Although misregulation of MLL family proteins has been associated with acute leukemia, the role of hSETD1A in cancer remains unknown. In this study, we report that hSETD1A and its associated H3K4me3 are up-regulated in human colorectal cancer (CRC) cells and patients. Depletion of hSETD1A inhibited CRC cell growth, colony formation, and tumor engraftment. Genome-wide expression profiling of CRC cells reveals that approximately 50% of Wnt/?-catenin target genes are affected by the hSETD1A knockdown (KD) suggesting that hSETD1A regulates a subset of canonical Wnt-signaling target genes. We further demonstrate that hSETD1A is recruited to promoters of those Wnt-signaling target genes through its interaction with ?-catenin, a master regulator of the Wnt-signaling pathway. The recruitment of the hSETD1A HMT complex confers promoter-associated H3K4me3 that leads to assembly of transcription preinitiation complex (PIC) and transcriptional activation. Furthermore, the expression levels of hSETD1A are positively correlated with H3K4me3 enrichment at the promoters of Wnt/?-catenin target genes and the aberrant activation of these genes in human CRC. These results provide new biologic and mechanistic insights into the cooperative role of hSETD1A and ?-catenin in regulation of Wnt target genes as well as in CRC cell growth in vitro and in vivo.
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Mode-expansion theory for inhomogeneous meta-surfaces.
Opt Express
PUBLISHED: 11-13-2013
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Modeling meta-surfaces as thin metamaterial layers with continuously varying bulk parameters, we employed a rigorous mode-expansion theory to study the scattering properties of such systems. We found that a meta-surface with a linear reflection-phase profile could redirect an impinging light to a non-specular channel with nearly 100% efficiency, and a meta-surface with a parabolic reflection-phase profile could focus incident plane wave to a point image. Under certain approximations, our theory reduces to the local response model (LRM) established for such problems previously, but our full theory has overcome the energy non-conservation problems suffered by the LRM. Microwave experiments were performed on realistic samples to verify the key theoretical predictions, which match well with full-wave simulations.
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Use of national pneumonia surveillance to describe influenza A(H7N9) virus epidemiology, China, 2004-2013.
Emerging Infect. Dis.
PUBLISHED: 11-12-2013
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In mainland China, most avian influenza A(H7N9) cases in the spring of 2013 were reported through the pneumonia of unknown etiology (PUE) surveillance system. To understand the role of possible underreporting and surveillance bias in assessing the epidemiology of subtype H7N9 cases and the effect of live-poultry market closures, we examined all PUE cases reported from 2004 through May 3, 2013. Historically, the PUE system was underused, reporting was inconsistent, and PUE reporting was biased toward A(H7N9)-affected provinces, with sparse data from unaffected provinces; however, we found no evidence that the older ages of persons with A(H7N9) resulted from surveillance bias. The absolute number and the proportion of PUE cases confirmed to be A(H7N9) declined after live-poultry market closures (p<0.001), indicating that market closures might have positively affected outbreak control. In China, PUE surveillance needs to be improved.
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Development of functionally selective, small molecule agonists at kappa opioid receptors.
J. Biol. Chem.
PUBLISHED: 11-01-2013
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The kappa opioid receptor (KOR) is widely expressed in the CNS and can serve as a means to modulate pain perception, stress responses, and affective reward states. Therefore, the KOR has become a prominent drug discovery target toward treating pain, depression, and drug addiction. Agonists at KOR can promote G protein coupling and ?arrestin2 recruitment as well as multiple downstream signaling pathways, including ERK1/2 MAPK activation. It has been suggested that the physiological effects of KOR activation result from different signaling cascades, with analgesia being G protein-mediated and dysphoria being mediated through ?arrestin2 recruitment. Dysphoria associated with KOR activation limits the therapeutic potential in the use of KOR agonists as analgesics; therefore, it may be beneficial to develop KOR agonists that are biased toward G protein coupling and away from ?arrestin2 recruitment. Here, we describe two classes of biased KOR agonists that potently activate G protein coupling but weakly recruit ?arrestin2. These potent and functionally selective small molecule compounds may prove to be useful tools for refining the therapeutic potential of KOR-directed signaling in vivo.
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Activation of farnesoid X receptor induces RECK expression in mouse liver.
Biochem. Biophys. Res. Commun.
PUBLISHED: 10-31-2013
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Farnesoid X receptor (FXR) belongs to the ligand-activated nuclear receptor superfamily, and functions as a transcription factor regulating the transcription of numerous genes involved in bile acid homeostasis, lipoprotein and glucose metabolism. In the present study, we identified RECK, a membrane-anchored inhibitor of matrix metalloproteinases, as a novel target gene of FXR in mouse liver. We found that FXR agonist substantially augmented hepatic RECK mRNA and protein expression in vivo and in vitro. FXR regulated the transcription of RECK through directly binding to FXR response element located within intron 1 of the mouse RECK gene. Moreover, FXR agonist reversed the down-regulation of RECK in the livers from mice fed a methionine and choline deficient diet. In summary, our data suggest that RECK is a novel transcriptional target of FXR in mouse liver, and provide clues to better understanding the function of FXR in liver.
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Universal immunogenicity validation and assessment during early biotherapeutic development to support a green laboratory.
Bioanalysis
PUBLISHED: 10-22-2013
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Immunogenicity support during nonclinical biotherapeutic development can be resource intensive if supported by conventional methodologies. A universal indirect species-specific immunoassay can eliminate the need for biotherapeutic-specific anti-drug antibody immunoassays without compromising quality. By implementing the Rs of sustainability (reduce, reuse, rethink), conservation of resources and greener laboratory practices were achieved in this study.
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Hollow, spherical nitrogen-rich porous carbon shells obtained from a porous organic framework for the supercapacitor.
ACS Appl Mater Interfaces
PUBLISHED: 10-08-2013
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Hollow, spherical nitrogen-rich porous carbon shells were prepared as supercapacitor electrode materials through the carbonization of structure-controlled porous organic frameworks at high temperature. The structure and electrochemical properties of the resulting carbonized materials were systematically characterized. Experimental results revealed that the nitrogen-rich hollow carbon spheres obtained at 800 °C were a kind of amorphous carbon with micropores on the shell frame and with specific surface areas as high as 525 m2 g(-1). The prepared porous carbon possessed a specific capacitance of 230 F g(-1) at a current density of 0.5 A g(-1) and could retain ?98% of the initial capacitance after 1500 successive charge-discharge cycles. Electrochemical impedance spectroscopy indicated that the material has a small equivalent series resistance (0.62 ?). All of these values demonstrated that the prepared porous carbon is a promising supercapacitor material. The proposed method represents a simple approach towards the preparation of unique structures of nitrogen-containing porous carbon that exhibit the advantages of having a simple preparation process, a wide availability of precursors, flexible control of the structure, and an easier adjustment of the amount of heteroatoms.
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Influence of hydrophilic amino acids and GC-content on expression of recombinant proteins used in vaccines against foot-and-mouth disease virus in Escherichia coli.
Biotechnol. Lett.
PUBLISHED: 10-01-2013
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Epitope-based protein expression in Escherichia coli can be improved by adjusting its amino acid composition and encoding genes. To that end, we analyzed 24 recombinant epitope proteins (rEPs) that carry multiple epitopes derived from VP1 protein of foot-and-mouth disease virus. High level expression of the rEPs was attributed to a high content of Arg, Asn, Asp and Thr, a low content of Gln, Pro and Lys, a high content of hydrophilic amino acids and a higher isoelectric point value resulting from abundant Arg. It is also attributed to the appropriate guanine and cytosine content in the encoding genes. The data provide a reference for adjusting the amino acid composition in designing epitope-based proteins used in vaccines and for adjusting the synonymous codons to improve their expressions in E. coli.
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Nd(3+) Sensitized Up/Down Converting Dual-Mode Nanomaterials for Efficient In-vitro and In-vivo Bioimaging Excited at 800?nm.
Sci Rep
PUBLISHED: 10-01-2013
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Core/shell1/shell2/shell3 structured NaGdF4:Nd/NaYF4/NaGdF4:Nd,Yb,Er/NaYF4 nanocrystals were well designed and synthesized, each of the parts assume respective role and work together to achieve dual-mode upconverting (UC) and downconverting (DC) luminescence upon the low heat effect 800-nm excitation. Nd(3+), Yb(3+), Er(3+) tri-doped NaGdF4:Nd,Yb,Er UC layer [NIR (800?nm)-to-Visible (540?nm)] with a constitutional efficient 800?nm excitable property were achieved for the in-vitro bioimaging with low auto-fluorescence and photo-damage effects. Moreover, typical NIR (800?nm)-to-NIR (860-895?nm) DC luminescence of Nd(3+) has also been realized with this designed nanostructure. Due to the low heat effect, high penetration depth of the excitation and the high efficiency of the DC luminescence, the in-vivo high contrast DC imaging of a whole body nude mouse was achieved. We believe that such dual-mode luminescence NCs will open the door to engineering the excitation and emission wavelengths of NCs and will provide a new tool for a wide variety of applications in the fields of bioanalysis and biomedical.
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[Expressions of CD133 and CD82/KAI1 in bladder urothelial carcinoma and their correlation with vasculogenic mimicry].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 09-27-2013
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To explore the expressions of CD133 and CD82/KAI1 in bladder urothelial carcinoma, their association with the clinicopathological factors and their roles in vasculogenic mimicry (VM) in the tumor.
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[Source profile of volatile carbonyl compounds in wastewater treatment plant of an oil refinery].
Huan Jing Ke Xue
PUBLISHED: 09-14-2013
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An observation was conducted at the wastewater treatment plant in a refinery in Guangdong province, using the PFPH-GC/MS method to analyze the composition and the concentration of volatile carbonyl compounds. The emission characteristics and the atmospheric chemical reactivity of these compounds were also studied. The results showed that 20 kinds of carbonyl compounds were detected with a concentration range of 0 to 68.80 microg x m(-3). The mean value of total concentration in all processing unit was (253.02 +/- 124.5) microg x m(-3). Background corrected concentrations showed that for each of the 6 treatment units of the plant, over 90% of the volatile carbonyl emissions were contributed by 14 of the 20 volatile carbonyl compounds, among which aldehyde was the most abundant with an average concentration of (44.74 +/- 20.89) microg x m(-3), followed by 2-butanone and acetaldehyde with average concentrations of (30.47 +/- 12.94) microg x m(-3) and (23.51 +/- 14.57) microg x m(-3), respectively. Several molecular markers were identified based on the analysis of the chemical activities and atmospheric lifetimes of the 20 carbonyl compounds. Finally, a source profile was established for the plant.
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Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-12-2013
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Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase C? (PLC?) signaling pathway with either a specific PLC? inhibitor or knockdown PLC? reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression.
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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.