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Find video protocols related to scientific articles indexed in Pubmed.
[Dynamic changes of intestinal 16S rDNA metagenome in 5 infants.]
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 11-20-2014
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To investigate the dynamic changes of intestinal 16S rDNA metagenome in healthy infants.
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Gelatin quantification by oxygen-18 labeling and liquid chromatography- high resolution mass spectrometry.
J. Agric. Food Chem.
PUBLISHED: 11-19-2014
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Combined with high-performance liquid chromatography (HPLC) and linear-ion trap/Orbitrap high-resolution mass spectrometry, trypsin catalyzed 16O-to-18O exchange was used to establish an accurate quantitative method for the bovine or porcine gelatin. The sophisticated modifications for these two mammalian gelatins were unambiguously identified by accurate mass and tandem mass spectrometry. Eighteen marker peptides were successfully identified for the bovine and porcine gelatin, respectively. The gelatins were subjected to 18O or 16O labeling in the presence of trypsin and mixed together in various ratios for quantification. All the 18O-labeled peptides were also confirmed by accurate mass and tandem mass spectrometry. The ten marker peptides with strongest signal were chosen to calculate the average ratios of 18O-labeled and 16O-labeled gelatin. The measured ratios of 18O-labeled and 16O-labeled peptides were very closed to the mixing ratios of 20:1, 5:1, 1:1 and 1:5 with low standard deviation values. The samples with mixing ratio of 1:1 18O-labeled and 16O-labeled peptides were determined to 1.00 and 0.99 with the standard deviation of 0.02 and 0.04 for bovine and porcine gelatins, respectively, indicating high accuracy of this method. Trypsin-catalyzed 18O labeling was proved to be an excellent internal calibrant for gelatins. When combined with HPLC and high resolution mass spectrometry, it is an accurate and sensitive quantitative method for gelatin in the food industry.
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Interactions between colloidal particles in the presence of an ultra-highly charged amphiphilic polyelectrolyte.
Langmuir
PUBLISHED: 11-15-2014
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A novel amphiphilic polyelectrolyte denoted as PAGC8 and a traditional amphiphilic polyelectrolyte denoted as PASC8 were prepared. PAGC8 consisted of gemini type surfactant segment based on 1, 3-bis (N, N-dimethyl-N-octylammonium)-2-propylacrylate dibromide, while PASC8 incorporated acryloyloxyethyl-N, N-dimethyl-N-dodecylammonium bromide as single chain surfactant units within its repeat unit structure. Turbidity, stability and zeta-potential measurements were performed in the presence of PAGC8 and PASC8, respectively, in order to evaluate their effectiveness in inducing solid/liquid separations. It was found that the maximum transmittance was observed before the zeta-potential values reached the isoelectric point, implying that not only charge neutralization but also charge-patch mechanism contributed to the separation process. Colloid probe atomic force microscopy technique was introduced to directly determine the interactions between surfaces in the presence of ultra-highly charged amphiphilic polyelectrolyte. Based on the AFM results, we have successfully interpreted the influence of the charge density of the polyelectrolytes on the phase stability. Electrostatic interaction played the dominant role in the flocculation processes, although both electrostatic interaction and hydrophobic effect provided contributions to the colloidal dispersions. The attractions upon surfaces approach in the case of PAGC8 were significantly larger than that of PASC8 due to the higher charge density. The strong peeling events upon retraction in the presence of PAGC8 implied that the hydrophobic effect was stronger than that of PASC8 which displayed the loose pulling events. A strong attraction was identi?ed at shorter separation distances for both systems. However, these interactions cannot be successfully described by the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory of colloid stability, due to the participation of charge-patch and strong hydrophobic effect. In order to account for the additional interactions, an extended DLVO empirical model was proposed to explain the non-DLVO forces in the systems. A reasonable physical model was also proposed to further describe the interactions between surfaces in the two amphiphilic polyelectrolyte systems.
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Protection of Murine Spermatogenesis Against Ionizing Radiation-Induced Testicular Injury by a Green Tea Polyphenol.
Biol. Reprod.
PUBLISHED: 11-15-2014
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Epigallocatechin-3-gallate (EGCG), a bioactive polyphenol in green tea, exerts anti-apoptotic activity and prevents tissue damage against different stimuli. Herein, we investigated the effects of EGCG treatment to simultaneously improve spermatogenesis following ionizing radiation (IR) (2 Gy). Mice were intraperitoneally injected with 50 mg/kg EGCG or vehicle ctrl 3 days prior to the irradiation and the treatment last intermittently for 24 days. Supplement with exogenous EGCG protected against short-term germ cell loss and attenuated IR-elicited testicular oxidative stress. Mechanistically, pro-survival effects of EGCG treatment upon IR stress were regulated, at least in part, via the mitogen-activated protein kinase/BCL2 family/caspase 3 pathway. Consistently, at Post-IR 21 days, histological analyses revealed tubule damage, desquamation of germ cells and impairment of caudal parameters in irradiated testis, which could be significantly improved by intermittent EGCG treatment. In addition, long-term EGCG application ameliorated the IR-induced blood--testicular barrier (BTB) permeability and suppressed testicular steroidogenesis, thus exerting a stimulatory effect on the spermatogenic recovery. Collectively, EGCG appeared to efficiently prevent germ cells from radiation-induced cell death via multiple mechanisms. Employment of this bioactive polyphenol should be an attractive strategy of fertility preservation in males exposed to conventional radiation therapy and warrants further investigation.
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Facile and Label-Free Detection of Lung Cancer Biomarker in Urine by Magnetically Assisted Surface-Enhanced Raman Scattering.
ACS Appl Mater Interfaces
PUBLISHED: 11-14-2014
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Adenosine plays a crucial role in the regulation of physiological activity in various tissues and organs. As adenosine is a possible biomarker for cancer, the determination of its level presents a demanding task for deeply monitoring progress of diseases. Through the synthesis of Fe3O4/Au/Ag nanocomposites weaved and stabilized by phytic acid and its salt, we develop a magnetically assisted surface enhanced Raman scattering (SERS) protocol to determine trace level adenosine in urine samples from both lung cancer patients and health human. The magnetic properties of the nanocomposites enable to realize the simple separation of targeted molecules from a complex matrix and the Au/Ag nanoparticles moieties act as the SERS platform. This label-free Fe3O4/Au/Ag-nanocomposites-based SERS protocol shows a good stability, reproducibility, time-efficiency (less than 20 min for one sample test) and huge sensitivity down to 10-10 M. The protocol also has high selectivity because SERS signal of adenosine provides the molecular fingerprint information as well as an azo coupling pretreatment is performed to remove the interference of urea. Furthermore, a SERS array is designed for on-site screening adenosine in urine samples in a massive way using a portable Raman. Such a magnetically assisted SERS method as a powerful alternative can be expected as a smart and promising tool for effective assessment of healthcare.
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Complete mitochondrial DNA sequence of Lepus tolai (Leporidae: Lepus).
Mitochondrial DNA
PUBLISHED: 11-13-2014
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Abstract In the present study, we determined the complete nucleotide sequence of the mitochondrial (mt) genome of tolai hare, Lepus tolai (Leporidae: Lepus) by using polymerase chain reaction (PCR) technique. The entire mtDNA sequence is 17,472 bp long and contains 13 protein-coding genes, two ribosomal RNA, 22 transfer RNA gens and one long non-coding region known as the control region.
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2-Deoxy-D-Glucose Enhances Anesthetic Effects in Mice.
Anesth. Analg.
PUBLISHED: 11-13-2014
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The mechanisms of general anesthesia by volatile drugs remain largely unknown. Mitochondrial dysfunction and reduction in energy levels have been suggested to be associated with general anesthesia status. 2-Deoxy-D-glucose (2-DG), an analog of glucose, inhibits hexokinase and reduces cellular levels of adenosine triphosphate (ATP). 3-Nitropropionic acid is another compound which can deplete ATP levels. In contrast, idebenone and L-carnitine could rescue deficits of energy. We therefore sought to determine whether 2-DG and/or 3-nitropropionic acid can enhance the anesthetic effects of isoflurane, and whether idebenone and L-carnitine can reverse the actions of 2-DG.
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Combination of 4-1BB Agonist and PD-1 Antagonist Promotes Anti-tumor Effector / Memory CD8 T cells in a Poorly Immunogenic Tumor Model.
Cancer Immunol Res
PUBLISHED: 11-13-2014
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Immunotherapies targeting Programmed death 1 (PD-1) co-inhibitory receptor have shown great promise for a subset of cancer patients. However, robust and safe combination therapies are still needed to bring the benefit of cancer immunotherapy to broader patient populations. In our effort to search for an optimal strategy of combinatorial immunotherapy, we have compared the anti-tumor activity of anti-4-1BB/anti-PD-1 combination with that of anti-PD-1/anti-LAG-3 combination in the poorly immunogenic B16F10 melanoma model. Pronounced tumor inhibition occurred only in animals receiving anti-PD-1 and anti-4-1BB concomitantly, while combining anti-PD-1 with anti-LAG-3 led to a modest degree of tumor suppression. The activity of anti-4-1BB/anti-PD-1 combination was dependent on IFN-? and CD8+ T cells. Both 4-1BB and PD-1 proteins were elevated on the surface of CD8+ T cells by anti-4-1BB/anti-PD-1 co-treatment. In the tumor microenvironment, an effective anti-tumor immune response was induced as indicated by increased CD8+/Treg ratio and the enrichment of genes such as CD3?, CD8?, IFN-? and Eomesodermin. In the spleen, the combination treatment shaped the immune system to an effector/memory phenotype and increased the overall activity of tumor-specific CD8+ CTLs, reflecting a long-lasting systemic anti-tumor response. Furthermore, combination treatment in C57BL/6 animals showed no additional safety signals, and only minimally increased severity of the known toxicity relative to 4-1BB agonist alone. Therefore, in the absence of any cancer vaccine, anti-4-1BB/anti-PD-1 combination therapy is sufficient to elicit a robust anti-tumor effector/memory T cell response in an aggressive tumor model and is therefore a candidate for combination trials in patients.
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Diagnostic and prognostic significance of suPAR in traumatic brain injury.
Neurol India
PUBLISHED: 11-13-2014
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Soluble urokinase plasminogen activator receptor (suPAR) is a highly sensitive marker that reflects increased inflammation and is positively correlated with pro-inflammatory biomarkers. The aim of this prospective observational study was to explore the relationship between the plasma concentration of suPAR and traumatic brain injury (TBI).
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Synthesis, crystal structures and two-photon absorption properties of triphenylamine cyanoacetic acid derivative and its organooxotin complexes.
Dalton Trans
PUBLISHED: 11-12-2014
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Three novel organooxotin complexes (, and ) were synthesized by reaction of (2-cyano-3-(4-(diphenylamino)phenyl) acrylic acid) with n-Bu2SnO, Ph3Sn(OH) and nBu6Sn2O. The structures of the three complexes have been confirmed by single-crystal X-ray diffraction analysis. The metal complex features a ladder framework while and show discrete structures. The UV-vis absorption, single-photon excited fluorescence (SPEF) and two-photon excited fluorescence (2PEF) of the complexes have been systematically studied, suggesting that the three metal complexes have strong two-photon absorption (2PA) and large 2PA cross-sections. It is noteworthy that possesses an enhanced two-photon absorption, and exhibits larger 2PA cross-section per molecular weight compared to . Finally, high anti-tumor activity of these three metal complexes has also been identified.
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Overexpression and Potential Regulatory Role of IL-17F in Pathogenesis of Chronic Periodontitis.
Inflammation
PUBLISHED: 11-12-2014
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The objective of this study was to investigate the expression level, clinical significance, and possible regulating role of IL-17F in patients of chronic periodontitis. Periodontal local tissues were obtained from chronic periodontitis (CP) and healthy controls (HC) for real-time PCR (RT-PCR) detection with IL-17F and IL-17A messenger RNA (mRNA). Primary human gingival fibroblasts (HGF) were derived from patients receiving crown-lengthening procedures. Efficiency of small interfering RNA (siRNA) of IL-17R to HGF cells were assessed by Western blot and RT-PCR. Recombinant IL-17F and IL-17A were used to stimulate the HGF cells compared with the control group. Aspects of the nuclear factor-kappa B (NF-?B) and extracellular signal-regulated kinase (ERK) signaling pathways were examined by Western blot. Production of pro-inflammatory cytokines induced by IL-17F and IL-17A was detected by RT-PCR. Statistical analysis was analyzed by SPSS software. It showed significantly elevated levels of IL-17F and IL-17A mRNA in CP gingival tissues compared with HC group (P?
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Design of A Novel Sorbent to Enhance Reactive Adsorption of Hydrogen Sulfide.
ACS Appl Mater Interfaces
PUBLISHED: 11-11-2014
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A series of novel zinc oxide-silica composites with three-dimensionally ordered macropores (3DOM) structure were synthesized via colloidal crystal template method and used as sorbents for hydrogen sulfide (H2S) removal at room temperature for the first time. The performances of the prepared sorbents were evaluated by dynamic breakthrough testing. The materials were characterized before and after adsorption using scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that the composite with 3DOM structure exhibited remarkable desulfurization performance at room temperature and the enhancement of reactive adsorption of hydrogen sulfide was attributed to the unique structure features of 3DOM composites; high surface areas, nano-crystalline ZnO and the well-ordered interconnected macroporous with abundant mesopores. The introduction of silica could be conducive to support the 3DOM structure and the high dispersion of zinc oxide. Moisture in the H2S stream plays a crucial role in the removal process. The effects of Zn/Si ratio and the calcination temperature of 3DOM composites on H2S removal were studied. It demonstrated that the highest content of ZnO could reach up to 73 wt% and the optimum calcination temperature was 500C. The multiple adsorption/regeneration cycles showed that the 3DOM ZnO-SiO2 sorbent is stable and the sulfur capacity can still reach 67.4% of that of the fresh sorbent at the 5th cycle. These results indicate that 3DOM ZnO-SiO2 composites will be a promising sorbent for H2S removal at room temperature.
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Efficacy and Safety of Hybrid Therapy for Helicobacter pylori Infection: A Systematic Review and Meta-Analysis.
Helicobacter
PUBLISHED: 11-11-2014
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To assess the efficacy and safety of hybrid therapy compared to other pre-existing therapies and to new therapies.
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[Imaging study of paravertebral muscle degeneration in degenerative lumbar instability].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 11-06-2014
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To compare the paravertebral muscle (such as multifidus, erector spinae, psoas muscle) changes between the patients with degenerative lumbar instability and normal person by MRI and to observe the degeneration of paravertebral muscles. To analyze the relationship between paravertebral muscle degeneration and lumbar curvature of degenerative lumbar instability.
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The association of mannose-binding lectin genetic polymorphisms with the risk of rheumatoid arthritis: a meta-analysis.
J. Recept. Signal Transduct. Res.
PUBLISHED: 10-29-2014
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Abstract Objective: To better understand the risks of rheumatoid arthritis (RA) and certain subsets conferred by mannose-binding lectin (MBL2) polymorphisms in different races. Materials and methods: Eighteen articles (4810 cases and 4585 controls) were identified from the latest literature search carried out in May 2014 using PubMed, Web of Science, Wanfang Database (Chinese) and Chinese National Knowledge Infrastructure. Three single nucleotide polymorphisms of codon 52, 54 and 57, exonic and extended genotypic variance in MBL2 were synthesized. Results: Codon 54 mutation of MBL2 was unlikely to be a risk factor for RA in overall population, but turned out to be deleterious in East Asian (four studies with 523 cases and 647 controls, pooled OR:1.63, 95% CI: 1.23-2.17). Codon 54 mutation increased the risk of seropositive and erosive RA by 44% and 162%, respectively (three studies with 281 cases and 358 controls, 95% CI: 1.01-2.05; 3 studies with 180 cases and 499 controls, 95% CI: 1.77-3.88). Furthermore, those risks were relatively stronger when restricted in East Asian (two studies with 147 cases and 244 controls, pooled OR: 1.85, 95% CI: 1.19-2.87; 2 studies with 170 cases and 291 controls, pooled OR: 2.78, 95% CI: 1.85-4.20). No remarkable associations were detected regarding codon 52, 57, exon 1 and extended genotype of MBL2. Conclusions: Polymorphism of codon 54 in MBL2 may predispose to RA, especially seropositive or erosive RA, which East Asian appears to be more vulnerable.
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[Analysis on the ecosystem structure and function of lake taihu based on ecopath model].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 10-28-2014
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Based on the data of lake survey conducted during 2008-2009 and the published data of the trophic ecology of key species, the exploited freshwater ecosystem of Lake Taihu was described using Ecopath with Ecosim 6.1 with the aim of characterizing its functioning and structure. The model comprised 20 functional groups including primary producers, the main species of fishes, nonfish vertebrates, and detritus. Results showed that the functional groups were organized into four aggregated trophic levels with the highest levels corresponding to the top predators, culters. Two trophic pathways were found in Lake Taihu, the detrital pathway and grazing pathway. The detrital pathway dominated in the ecosystem. As a consequence of the low ecotrophic efficiency of primary producer and detritus (trophic level I ), the accumulating detrital sediments continually released waste nutrients back into the system, resulting in its internal pollution. Considering Odum and Ulanowicz's theory of ecosystem development, the ecosystem was placed on a low developmental stage with high net primary production (NPP), net primary production/total respiration (NPP/R) and lower connectance index (CI), system omnivory index (SOI), and Finn' s cycling index (FCI). The results of mixed trophic impacts and keystone species selection showed that the increasingly intensive fishing exerted a negative effect on the ecosystem, and the top-down effects of top predators were becoming much obviously reduced.
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Mechanistic Understanding of Translational Pharmacokinetic-Pharmacodynamic Relationships in Nonclinical Tumor Models: A Case Study of Orally Available Novel Inhibitors of Anaplastic Lymphoma Kinase.
Drug Metab. Dispos.
PUBLISHED: 10-27-2014
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The orally available novel small molecules, PF06463922 and PF06471402, are second-generation anaplastic lymphoma kinase (ALK) inhibitors targeted to both naive- and resistant-patients with non-small cell lung cancer (NSCLC) to the first-generation ALK inhibitor, crizotinib. The objectives of the present study were to characterize and compare pharmacokinetic-pharmacodynamic (PKPD) relationships of PF06463922 and PF06471402 for target modulation in tumor and antitumor efficacy in athymic mice implanted with H3122 NSCLC cells expressing a crizotinib-resistant EML4-ALK mutation (EML4-ALK(L1196M)). Furthermore, the PKPD relationships for these ALK inhibitors were evaluated and compared between oral administration and subcutaneous constant infusion, i.e., between different pharmacokinetic profiles. Oral and subcutaneous pharmacokinetic profiles of these ALK inhibitors were adequately described by a one-compartment pharmacokinetic model. An indirect response model extended with a modulator fit the time-courses of PF06463922- and PF06471402-mediated target modulation (i.e., ALK phosphorylation) with estimated unbound EC50,in vivo of 36 and 20 nM, respectively, for oral administration, and 100 and 69 nM, respectively, for subcutaneous infusion. A drug-disease model based on the turnover concept fit tumor growth curves inhibited by PF06463922 and PF06471402 with estimated unbound tumor stasis concentrations of 51 and 27 nM, respectively, for oral administration, and 116 and 70 nM, respectively, for subcutaneous infusion. Thus, the EC50,in vivo to EC60,in vivo estimates for ALK inhibition corresponded to the concentrations required tumor stasis in all cases, suggesting that the pharmacodynamic relationships of target modulation to antitumor efficacy were consistent among the ALK inhibitors, even when the pharmacokinetic profiles with different administration routes were considerably different.
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[Effects of fenofibrate on the growth and migration of ovarian cancer cells in vitro].
Sichuan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 10-25-2014
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To investigate the effects of fenofibrate, a lipid-lowering drug, on the growth and migration of human ovarian cancer cells SKOV3 in vitro.
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Zinc finger nucleases targeting the human papillomavirus E7 oncogene induce E7 disruption and a transformed phenotype in HPV 16/18-positive cervical cancer cells.
Clin. Cancer Res.
PUBLISHED: 10-23-2014
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Purpose: Cervical cancer is mainly caused by infections of high-risk human papillomavirus (HR-HPV). Persistent expression of HR-HPV oncogenes E6 and E7 is implicated in malignant transformation. The aim was to provide proof-of-concept data to support use of zinc finger nucleases (ZFNs) targeting HPV E7 to treat HPV-related cervical cancer. Experimental Design: We designed and constructed ZFNs that could specifically recognize and cleave HPV16/18 E7 DNA. We tested the cleavage efficiency of selected ZFN16-E7-S2 and ZFN18-E7-S2 by using single strand annealing (SSA) assay. Cell viability and colony formation assays were used to estimate the inhibition of cell growth that received treatments of ZFNs. Gene disruption of HPV E7 and downstream genes were examined by Western blotting. Cell apoptosis assay were used to test the specificity and efficiency of induction of HPV type-specific apoptosis. We also introduced xenograft formation assays to estimate the potential of inhibition of HPV-related disease. Results: We found ZFN16-E7-S2 and ZFN18-E7-S2 disrupted HPV E7 oncogenes in HPV16/18-positive cervical cancer cells. Both ZFNs effectively leaded to inhibition of type -specific cervical cancer cell growth, and specifically induced apoptosis of corresponding HPV16- and HPV18-positive cervical cancer cell lines. ZFN16-E7-S2 and ZFN18-E7-S2 also repressed xenograft formation in vivo. Conclusion: ZFNs targeted HPV16/18 E7 could effectively induce disruption of E7 oncogenes, lead to type-specific and efficient growth inhibition and apoptosis of HPV-positive cells. ZFNs targeted HPV16/18 E7 oncogenes could be used as novel therapeutic agents for the treatment of HPV-related cervical cancer.
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A Missense Mutation in HK1 Leads to Autosomal Dominant Retinitis Pigmentosa.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 10-16-2014
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Retinitis pigmentosa (RP) is a genetically heterogeneous disease with over 60 causative genes known to date. Nevertheless, approximately 40% of RP cases remain genetically unsolved, suggesting that many novel disease-causing genes are yet to be identified. In this study, we aimed to identify the causative mutation for a large autosomal dominant RP (adRP) family with negative results from known retinal disease gene screening.
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Direct regioselective phosphonation of heteroaryl N-oxides with H-phosphonates under metal and external oxidant free conditions.
Chem. Commun. (Camb.)
PUBLISHED: 10-11-2014
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A direct C-H/P-H functionalization of heteroaryl N-oxides with H-phosphonates is described. A wide variety of heteroaryl phosphonates were obtained in up to 92% yield in a chemo- and regioselective manner, under oxidant and metal free conditions. This procedure features practicality, high efficiency, environmental friendliness and atom economy.
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Coronary Computed Tomographic Angiography in Coronary Artery Bypass Grafts: Comparison Between Low-Concentration Iodixanol 270 and Iohexol 350.
J Comput Assist Tomogr
PUBLISHED: 10-10-2014
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The aim of this study was to evaluate the feasibility of low-concentration iso-osmolar Iodixanol 270 compared with Iohexol 350 in patients with coronary artery bypass grafts (CABGs) undergoing coronary computed tomographic angiography (CCTA).
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[Effects of resting days on live poultry markets in controlling the avian influenza pollution].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 10-09-2014
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To analyze the results of nine-round environmental specimen surveillance programs in five live poultry markets pre-, during and post the 'closing days' and to evaluate the effects of 'closing days' on live poultry markets regarding the control against avian influenza pollution.
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Simultaneous determination of five anthraquinones in a Chinese traditional preparation by RP-HPLC using an improved extraction procedure.
J Integr Med
PUBLISHED: 10-09-2014
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The stable quality of Chinese herbal medicines is a critical factor for their reliable clinical efficiency. An improved liquid-liquid extraction procedure and a liquid chromatographic method were developed to simultaneously analyze five anthraquinones (aloe-emodin, rhein, emodin, chrysophanol and physcion) in a Chinese traditional hospital preparation, Fuyankang mixture, in order to quantitatively control its quality in a more effective way.
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Effect of current density on the microstructure and corrosion resistance of microarc oxidized ZK60 magnesium alloy.
Biointerphases
PUBLISHED: 10-05-2014
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The application of magnesium alloys as biomaterials is limited by their poor corrosion behavior. Microarc oxidation (MAO) treatment was used to prepare ceramic coatings on ZK60 magnesium alloys in order to overcome the poor corrosion resistance. The process was conducted at different current densities (3.5 and 9.0?A/dm(2)), and the effect of current density on the process was studied. The microstructure, elemental distribution, and phase composition of the MAO coatings were characterized by scanning electron microscopy, energy-dispersive x-ray spectrometry, and x-ray diffraction, respectively. The increment of current density contributes to the increase of thickness. A new phase Mg2SiO4 was detected as the current density increased to 9.0?A/dm(2). A homogeneous distribution of micropores could be observed in the coating produced at 3.5?A/dm(2), while the surface morphology of the coating formed at 9.0?A/dm(2) was more rough and apparent microcracks could be observed. The coating obtained at 3.5?A/dm(2) possessed a better anticorrosion behavior.
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Effects of bacterial communities on biofuel-producing microalgae: stimulation, inhibition and harvesting.
Crit. Rev. Biotechnol.
PUBLISHED: 09-30-2014
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Abstract Despite the great interest in microalgae as a potential source of biofuel to substitute for fossil fuels, little information is available on the effects of bacterial symbionts in mass algal cultivation systems. The bacterial communities associated with microalgae are a crucial factor in the process of microalgal biomass and lipid production and may stimulate or inhibit growth of biofuel-producing microalgae. In addition, we discuss here the potential use of bacteria to harvest biofuel-producing microalgae. We propose that aggregation of microalgae by bacteria to achieve >90% reductions in volume followed by centrifugation could be an economic approach for harvesting of biofuel-producing microalgae. Our aims in this review are to promote understanding of the effects of bacterial communities on microalgae and draw attention to the importance of this topic in the microalgal biofuel field.
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Scrapie Infection in Experimental Rodents and SMB-S15 Cells Decreased the Brain Endogenous Levels and Activities of Sirt1.
J. Mol. Neurosci.
PUBLISHED: 09-28-2014
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Prion diseases are composed of a group of fatal neurodegenerative disorders resulting from misfolding of cellular prion (PrP(C)) into scrapie prion (PrP(Sc)). Sirt1, a class III histone deacetylase, has been reported to protect neuronal cells against PrP (106-126)-induced cell death. To address the potential role of Sirt1 during prion infection, the levels and enzyme activities of Sirt1 in the brains of scrapie-infected rodents, including hamsters infected with strain 263K, mice infected with strains 139A and ME7, and in prion infected SMB-S15 cells, were analyzed. Western blots revealed that endogenous Sirt1 levels were significantly decreased in all tested scrapie-infected models. Dynamic assays of brain Sirt1 levels in 263K-infected hamsters during incubation period showed a time-dependent decrease. The acetylating forms of Sirt1 target proteins, P53, PGC-1, and STAT3, markedly increased both in the brains of scrapie-infected rodents and in SMB-S15 cells, representing decreased Sirt1 activity. Immunofluorescent assays illustrated that Sirt1 predominately localized in cytosol of SMB-S15 cells but clearly distributed in nucleus of its normal partner cell line, SMB-PS. Moreover, accompanying with increase of Sirt1 level and decrease of acetyl-P53 level, treatments with Sirt1 activators SRT1720 and resveratrol in SMB-S15 cells significantly reduced PrP(Sc); at the same time, the cellular distribution of PrP proteins became normal, and the cell proliferating state was slightly improved. These data indicate that prion infection notably attenuates the Sirt1 activity in host cells. Sensitivity of the PrP(Sc) to Sirt1 activators highlights a potential role of Sirt1 in prion therapeutics.
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A Novel Targeted Learning Method for Quantitative Trait Loci Mapping.
Genetics
PUBLISHED: 09-27-2014
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We present a novel semiparametric method for quantitative trait loci (QTL) mapping in experimental crosses. Conventional genetic mapping methods typically assume parametric models with Gaussian errors and obtain parameter estimates through maximum likelihood estimation. In contrast with univariate regression and interval mapping methods, our model requires fewer assumptions and also accommodates various machine learning algorithms. Estimation is performed with targeted maximum likelihood learning methods. We demonstrate our semiparametric targeted learning approach in a simulation study and a well-studied barley dataset.
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Gold nanoparticles with tipped surface structures as substrates for single-particle surface-enhanced Raman spectroscopy: concave nanocubes, nanotrisoctahedra, and nanostars.
ACS Appl Mater Interfaces
PUBLISHED: 09-26-2014
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We demonstrate that Au nanoparticles with tipped surface structures, such as concave nanocubes, nanotrisoctahedra, and nanostars, possess size-dependent tunable plasmon resonances and intense near-field enhancements exploitable for single-particle surface-enhanced Raman spectroscopy (spSERS) under near-infrared excitation. We report a robust seed-mediated growth method for the selective fabrication of Au concave nanocubes, nanotrisoctahedra, and nanostars with fine-controlled particle sizes and narrow size distributions. Through tight control over particle sizes, the plasmon resonances of the nanoparticles can be fine-tuned over a broad spectral range with respect to the excitation laser, allowing us to systematically quantify the SERS enhancements on individual nanoparticles as a function of particle size for each particle geometry. Understanding of the geometry-dependent plasmonic characteristics and SERS activities of the nanoparticles is further enhanced by finite-difference time-domain (FDTD) calculations. Our results clearly show that strong SERS enhancements can be obtained and further optimized on individual Au nanoparticles with nanoengineered "hot spots" on their tipped surfaces when the plasmon resonances of the nanoparticles are tuned to the optimal spectral regions with respect to the excitation laser wavelength. Using tunable plasmonic nanoparticles with tipped surface structures as substrates for spSERS represents a highly promising and feasible approach to the optimization of SERS-based sensing and imaging applications.
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LIM and SH3 Protein 1 Induces TGF?-Mediated Epithelial-Mesenchymal Transition in Human Colorectal Cancer by Regulating S100A4 Expression.
Clin. Cancer Res.
PUBLISHED: 09-24-2014
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The expression of LIM and SH3 protein 1 (LASP1) was upregulated in colorectal cancer cases, thereby contributing to the aggressive phenotypes of colorectal cancer cells. However, we still cannot decipher the underlying molecular mechanism associated with colorectal cancer metastasis.
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[Effects of combined pollution of Cd, Cu and Pb on antioxidant enzyme activities of earthworm in soils].
Huan Jing Ke Xue
PUBLISHED: 09-24-2014
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Recently, soil heavy metal contamination becomes more and more serious in certain areas in China. Adverse effect caused by heavy metals in contaminated soils has been a wide concern for many years. In this study, a bioassay experiment with the earthworm (Eisenia foetida) was conducted to investigate the effects of compound application of Cd, Cu and Pb in soil on surperoxide dismutase (SOD), glutathione S-transferase (GST) and acid phosphatase (AP) activity in earthworms. Through a method of greenhouse soil experiment, this study utilized a uniform design method of three factors and six levels (Cd: 0-15 mg x kg(-1), Cu: 0-175 mg x kg(-1), Pb: 0-600 mg x kg(-1)) to research the physiological property and enrichment characteristics of earthworm in soils with Cd, Cu and Pb compound pollution. The activity of SOD, GST and AP were inhibited significantly under Cd, Cu and Pb compound pollution. And they were impacted by both time and heavy metal contents in the soil. Compared with the control sample, the activity of SOD increased by 7.4% -240.5% in the first eight days under the stress of heavy metals. But owing to the extremely severe stress, it was suppressed and descended by 19.4% -69.7%. Compared with the control sample, the activity of GST increased by 104.3% -217.3% in the first sixteen days under the stress of heavy metals. But owing to the extremely severe stress, it was suppressed and descended by 1.2% - 40.3%. The activity of AP changed over time in a trend of "increase, decrease, increase, decrease". Compared with the control sample, the activity of AP decreased by 9.2% -37.8% in the first eight days, then increased by 37.2% -117.2% in sixteenth days and decreased by 24.3% -34.0% to the last day. The analysis demonstrates that Pb and Cd-Cu-Pb is the dominant factor to the activity of SOD, while Cd and Cu were the dominant factors to the activity of GST and AP.
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Three dysregulated microRNAs in serum as novel biomarkers for gastric cancer screening.
Med. Oncol.
PUBLISHED: 09-23-2014
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Gastric cancer (GC) is one of the most threatening diseases. The symptoms of GC are complex and hard to detect, which also contribute to the poor prognosis of GC. Besides, the current diagnosis for GC is expensive and invasive. Thus, a fast, noninvasive biomarker is urgently needed for GC screening. MicroRNAs (miRNAs) are small noncoding RNAs, which are involved in a great variety of pathological processes, particularly carcinogenesis. MiRNAs are stable in gastric juice, plasma as well as serum, which facilitate it to be a promising biomarker for cancer. In this study, we selected three novel miRNAs, i.e., miR-233, miR-16, and miR-100, to investigate their potential diagnostic value in GC screening. A total of 50 GC patients and 47 healthy controls were involved in this study. Blood serum samples were collected; RNAs were extracted and normalized with U6 snRNA as the internal control; qRT-PCR was performed for relative expression of target miRNAs. Levels of miRNAs expression were compared by Student's t test for the comparison between two groups, and one-way ANOVA was used for multiple comparisons. The expression of miR-223, miR-16, and miR-100 was all significantly higher in GC patients than controls (all P < 0.001). All the tested miRNAs were manifested to be valuable biomarkers for GC. Relative expression of these miRNAs was significantly correlated with clinical characteristics of GC patients, such as TNM stage (P = 0.036 for miR-223; P < 0.001 for miR-100), metastatic status (P = 0.045 for miR-223; P = 0.031 for miR-16; P = 0.006 for miR-100), tumor size (P = 0.042 for miR-223; P = 0.031 for miR-16; P < 0.001 for miR-100), and differentiation grade (P = 0.036 for miR-223; P = 0.030 for miR-16; P = 0.034 for miR-100). However, in T classification, which considered both tumor size and direct extent of primary tumor, the difference in target miRNAs expression was not significant. In summary, we confirmed the diagnostic value of serum miR-223, miR-16, and miR-100 in GC. Significantly elevated expression of the three miRNAs was also observed in advanced GC patients, which suggested their availability in cancer staging.
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Magnetic/NIR-thermally responsive hybrid nanogels for optical temperature sensing, tumor cell imaging and triggered drug release.
Nanoscale
PUBLISHED: 09-23-2014
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The paper demonstrates a class of multifunctional core-shell hybrid nanogels with fluorescent and magnetic properties, which have been successfully developed for simultaneous optical temperature sensing, tumor cell imaging and magnetic/NIR-thermally responsive drug carriers. The as-synthesized hybrid nanogels were designed by coating bifunctional nanoparticles (BFNPs, fluorescent carbon dots embedded in the porous carbon shell and superparamagnetic iron oxide nanocrystals clustered in the core) with a thermo-responsive poly(N-isopropylacrylamide-co-acrylamide) [poly(NIPAM-AAm)]-based hydrogel as the shell. The BFNPs in hybrid nanogels not only demonstrate excellent photoluminescence (PL) and photostability due to the fluorescent carbon dots embedded in the porous carbon shell, but also has targeted drug accumulation potential and a magnetic-thermal conversion ability due to the superparamagnetic iron oxide nanocrystals clustered in the core. The thermo-responsive poly(NIPAM-AAm)-based gel shell can not only modify the physicochemical environment of the BFNPs core to manipulate the fluorescence intensity for sensing the variation of the environmental temperature, but also regulate the release rate of the loaded anticancer drug (curcumin) by varying the local temperature of environmental media. In addition, the carbon layer of BFNPs can adsorb and convert the NIR light to heat, leading to a promoted drug release under NIR irradiation and improving the therapeutic efficacy of drug-loaded hybrid nanogels. Furthermore, the superparamagnetic iron oxide nanocrystals in the core of BFNPs can trigger localized heating using an alternating magnetic field, leading to a phase change in the polymer gel to trigger the release of loaded drugs. Finally, the multifunctional hybrid nanogels can overcome cellular barriers to enter the intracellular region and light up the mouse melanoma B16F10 cells. The demonstrated hybrid nanogels would be an ideal system for the biomedical applications due to their excellent optical properties, magnetic properties, high drug loading capacity and responsive drug release behavior.
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Complete mitochondrial DNA sequence of Lepus sinensis (Leporidae: Lepus).
Mitochondrial DNA
PUBLISHED: 09-23-2014
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Abstract In the present study, we determined the complete nucleotide sequence of the mitochondrial (mt) genome of Chinese hare, Lepus sinensis (Leporidae: Lepus) by using polymerase chain reaction (PCR) technique. The entire mtDNA sequence is 17438 nucleotides long and contains 13 protein-coding genes, 2 ribosomal tRNA 22 transfer RNA gens and one long non-coding region known as the control region. The mt gene arrangement of L. sinensis is identical to those typical for vertebrates.
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Association of variants on ADIPOQ and AdipoR1 and the prognosis of gastric cancer patients after gastrectomy treatment.
Mol. Biol. Rep.
PUBLISHED: 09-20-2014
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Adiponectin is a protein hormone secreted exclusively by adipocytes and it is responsible for insulin sensitization in the human body. Deregulation of adiponectin and its downstream signaling pathway genes have been found to be involved in the gastric cancer carcinogenesis; however, whether the variants on adiponectin (ADIPOQ) and adiponectin receptor 1 (ADIPOR1) affect the prognosis of gastric cancer patients are still unknown. Here we have recruited 455 gastric cancer patients, who have received the gastrectomy treatment to evaluate the prognostic effects of variants on ADIPOQ (rs266729 and rs822395) and AdipoR1 (rs12733285 and rs1342387) for the gastric cancer patients. No significant association between the four variants and the overall survival of the gastric cancer patients was found. However, for those patients without a previous history of alcohol drinking, the rs266729 GG/CG genotype carriers showed a significantly decreased gastric cancer mortality compared to homogeneity CC patients (HR 0.74, 95 % CI 0.56-0.97; p = 0.032) after adjustment for variants age, sex, smoking status, tumor stage, tumor location and post-surgery chemotherapy. No significant association between the variant rs266729 genotypes and overall survival for the gastric cancer patients with an alcohol drinking habit. These data suggested that the variant rs266729 was an independent prognostic factor for the never drinking gastric cancer patients who received surgical treatment.
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Mycoplasma gallisepticum MGA_0676 is a membrane-associated cytotoxic nuclease with a staphylococcal nuclease region essential for nuclear translocation and apoptosis induction in chicken cells.
Appl. Microbiol. Biotechnol.
PUBLISHED: 09-18-2014
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Mycoplasma gallisepticum can infect a wide variety of birds including the commercial poultry. M. gallisepticum MGA_0676 is a putative lipoprotein, which is similar to bacterial thermostable nucleases. But the possible pathogenic effect of M. gallisepticum MGA_0676 has not been investigated so far. In the present study, we cloned the MGA_0676 gene after deletion of the amino-terminal signal sequence and mutagenesis of the Mycoplasma TGA tryptophan codons to TGG and expressed recombinant MGA_0676 protein in Escherichia coli. We identified and characterized MGA_0676 as a Ca(2+)-dependent cytotoxic nuclease of M. gallisepticum with a staphylococcal nuclease (SNc) region that displays the hallmarks of nucleases. Membrane protein immunoblot analysis and immunogold electron microscopy revealed that MGA_0676 locates on the membrane surface of M. gallisepticum. Furthermore, apoptosis assay using annexin V-FITC and propidium iodide (annexin V/PI) indicated that MGA_0676 played significant roles in apoptosis induction and pathological damages in chicken cells. Moreover, confocal microscopy showed that MGA_0676 localizes in the nuclei of host cells. Besides, after the SNc region was deleted, MGA_0676 lost its ability of nuclear localization, nuclease activity, and cytotoxicity, which revealed that the SNc region is essential for nuclear translocation and induction of apoptosis in chicken cells. The above results suggest that MGA_0676 is an important virulence factor in cellular pathology and may play a unique role in the life cycle events of M. gallisepticum.
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The Miaoyao Fanggan Sachets regulate humoral immunity and cellular immunity in mice.
J Complement Integr Med
PUBLISHED: 09-17-2014
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Abstract Background: Although some studies in the southeast part of Guizhou Province have suggested that Miaoyao Fanggan Sachets (MFS) prevent influenza, little is known about its influence on immune systems. Influenza virus mainly infects immune-compromised individuals. The effects of MFS have mainly been recognized in clinical practice. However, there have been relatively few studies on its biological mechanism. Here we investigated whether MFS was able to affect the mucosal immunization and the activation of alveolar macrophages (AM), CD4+and CD8+ T-cells in vivo. Methods: Eighty Kunming male mice were treated with MFS continuously or intermittently with Yu-Ping-Feng powder (YPF-P) (positive control group) or with normal saline (NS) (control group) for 4 weeks, respectively. Mice treated with MFS were further divided into the continuous inhalation group (12 h daily/4 weeks) and the discontinuous inhalation group (1 h, three times a day for 4 weeks). Mice in both groups were placed under 0.5 m3 masks which had four ventilation holes (10×15 cm) containing 40 g MFS. Positive control mice were orally treated with YPF-P 0.2 mg/10 g/day once a day for 4 weeks. Control mice were orally treated with equal volumes of NS once a day for 4 weeks. MFS was replaced every 6 days. Administration of YPF-P was used as a positive control since it has been used as an established Traditional Chinese Medicine (TCM) treatment before. After 4 weeks, mice in all experimental groups were sacrificed. IgA and IgG1 in lung and blood serum were detected by Western blot and enzyme-linked immuno sorbent assay (ELISA). The expression of alveolar macrophages (AM) in mice was analyzed by immunochemistry test based on CD68+staining. Blood samples were collected in which CD4+and CD8+T-cells were analyzed by flow cytometry. Results: Mice continuously and intermittently inhaling MFS showed a moderate increase in IgA and IgG1 protein levels compared with mice in the control groups. There was also a slightly significant increase in the number of AM in the continuous inhalation group compared with mice in the control groups (p<0.05). Furthermore, compared with controls, there was also a slightly significant increase in the number and percentage of CD4+and CD8+T-cells in both the continuous inhalation group and the discontinuous inhalation group (p<0.05). Conclusions: MFS was able to up-regulate the protein levels of sIgA and IgG1. Meanwhile, MFS could activate AM, CD4+and CD8+T-cells in mice. Our data have, for the first time, demonstrated that the protection against influenza by MFS is partly through activation of the innate and adaptive cell-mediated immune responses, indicating MFS as a potential new immune-modulatory agent for respiratory tract infectious disease.
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[Clinical features of Bardet-Biedl syndrome with renal abnormalities as initial manifestations].
Zhonghua Er Ke Za Zhi
PUBLISHED: 09-17-2014
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To study the clinical characteristics and diagnostic methods of rare autosomal recessive inherited Bardet-Biedl syndrome in patients presented with renal abnormalities.
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TET2 mutations predict response to hypomethylating agents in myelodysplastic syndrome patients.
Blood
PUBLISHED: 09-15-2014
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Only a minority of myelodysplastic syndrome (MDS) patients respond to hypomethylating agents (HMAs), but strong predictors of response are unknown. We sequenced 40 recurrently mutated myeloid malignancy genes in tumor DNA from 213 MDS patients collected before treatment with azacitidine (AZA) or decitabine (DEC). Mutations were examined for association with response and overall survival. The overall response rate of 47% was not different between agents. Clonal TET2 mutations predicted response (odds ratio [OR] 1.99, P = .036) when subclones unlikely to be detected by Sanger sequencing (allele fraction <10%) were treated as wild-type (WT). Response rates were highest in the subset of TET2 mutant patients without clonal ASXL1 mutations (OR 3.65, P = .009). Mutations of TP53 (hazard ratio [HR] 2.01, P = .002) and PTPN11 (HR 3.26, P = .006) were associated with shorter overall survival but not drug response. Murine-competitive bone marrow transplantation followed by treatment with AZA demonstrated that Tet2-null cells have an engraftment advantage over Tet2-WT cells. AZA significantly decreased this advantage for Tet2-null cells (P = .002) but not Tet2-WT cells (P = .212). Overall, Tet2 loss appears to sensitize cells to treatment with AZA in vivo, and TET2 mutations can identify patients more likely to respond to HMAs.
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Chronic Cardiovascular Disease-Associated Gene Network Analysis in Human Umbilical Vein Endothelial Cells Exposed to 2,3,7,8-Tetrachlorodibenzo-p-dioxin.
Cardiovasc. Toxicol.
PUBLISHED: 09-14-2014
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The association of dioxin exposure with increased morbidity or mortality of chronic cardiovascular diseases (CVDs) has been established by many epidemiological studies. However, the precise global gene expression alterations caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the cardiovascular system need to be further elucidated. In this study, we profiled the gene expression of human umbilical vein endothelial cells (HUVECs) exposed to different concentrations of TCDD by high-throughput sequencing. Expression of 1,838 genes was changed significantly after TCDD stimulation. The FunDO analysis suggested that some CVDs were highly associated with TCDD treatment, including atherosclerosis, thromboangiitis obliterans, pulmonary arterial hypertension (PAH), and hypertension. KEGG pathway analysis showed that many genes in the signaling pathways of vascular smooth muscle contraction and apoptosis were altered distinctly. In addition, we revealed evidence regarding the gene network changes of chronic CVDs including atherosclerosis, thrombosis, myocardial infarction (MI), hypertension, and PAH in TCDD-exposed HUVECs. We found that gene expression of ?1-adrenoceptors (ADRB1), ?2-adrenoceptors (ADRB2), endothelin-converting enzyme 1 (ECE1), and endothelin-1 gene (EDN1) that are involved in the blood pressure regulation pathway decreased apparently under TCDD treatment. Moreover, the transcripts of interleukin 1 beta (IL-1?) and tumor necrosis factor ? (TNF?), which are related to atherosclerosis, were up-regulated by TCDD stimulation. In addition, the transcripts of Homo sapiens collagen, type IV, alpha 1 (COL4A1), and isoforms that trigger the MI pathway were up-regulated after TCDD exposure. Finally, we found enhanced platelet-derived growth factor (PDGF) and signal transducer and activator of transcription 5 (Stat5) expression with TCDD treatment in endothelial cells, which are involved in PAH induced by vascular injury.
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Gas-liquid interface-mediated room-temperature synthesis of "clean" PdNiP alloy nanoparticle networks with high catalytic activity for ethanol oxidation.
Chem. Commun. (Camb.)
PUBLISHED: 09-13-2014
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PdNiP alloy nanoparticle networks (PdNiP NN) were prepared by simultaneous reduction of PdCl2, NiCl2 and NaH2PO2 with NaBH4via a gas-liquid interface reaction at room temperature using N2 bubbles. PdNiP NN had markedly higher activity and durability for ethanol oxidation than PdNi nanoparticle networks and PdNiP grain aggregates.
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Fluorine-18-deoxyglucose positron emission tomography/computed tomography with Ki67 and GLUT-1 immunohistochemistry for evaluation of the radiosensitization effect of oleanolic acid on C6 rat gliomas.
Nucl Med Commun
PUBLISHED: 09-12-2014
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The aim of this study was to investigate the radiosensitization effect of oleanolic acid (OA) in an in-vivo C6 rat glioma model using fluorine-18-deoxyglucose PET/computed tomography (F-FDG PET/CT) and Ki67 and glucose transporter-1 (GLUT-1) immunohistochemistry (IHC) and evaluate the utility of F-FDG PET/CT in assessing early changes after radiotherapy.
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Effect of type-2 astrocytes on the viability of dorsal root ganglion neurons and length of neuronal processes.
Neural Regen Res
PUBLISHED: 09-11-2014
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The role of type-2 astrocytes in the repair of central nervous system injury remains poorly understood. In this study, using a relatively simple culture condition in vitro, type-2 astrocytes, differentiated from oligodendrocyte precursor cells by induction with bone morphogenetic protein-4, were co-cultured with dorsal root ganglion neurons. We examined the effects of type-2 astrocytes differentiated from oligodendrocyte precursor cells on the survival and growth of dorsal root ganglion neurons. Results demonstrated that the number of dorsal root ganglion neurons was higher following co-culture of oligodendrocyte precursor cells and type-2 astrocytes than when cultured alone, but lower than that of neurons co-cultured with type-1 astrocytes. The length of the longest process and the length of all processes of a single neuron were shortest in neurons cultured alone, followed by neurons co-cultured with type-2 astrocytes, then neurons co-cultured with oligodendrocyte precursor cells, and longest in neurons co-cultured with type-1 astrocytes. These results indicate that co-culture with type-2 astrocytes can increase neuronal survival rate and process length. However, compared with type-1 astrocytes and oligodendrocyte precursor cells, the promotion effects of type-2 astrocytes on the growth of dorsal root ganglion neurons were weaker.
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[Role of PI3K/Akt signaling in hydrogen sulfide-induced alteration in expression of collagen I and III in hepatic stellate cells].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 09-10-2014
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To investigate the role of the PI3K/Akt signaling pathway in hydrogen sulfide-induced alterations in expression of collagen I and collagen III in hepatic stellate cells.
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Univariate and multiple linear regression analyses for 23 single nucleotide polymorphisms in 14 genes predisposing to chronic glomerular diseases and IgA nephropathy in Han Chinese.
Saudi J Kidney Dis Transpl
PUBLISHED: 09-07-2014
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Immunoglobulin A nephropathy (IgAN) is a complex trait regulated by the interaction among multiple physiologic regulatory systems and probably involving numerous genes, which leads to inconsistent findings in genetic studies. One possibility of failure to replicate some single-locus results is that the underlying genetics of IgAN nephropathy is based on multiple genes with minor effects. To learn the association between 23 single nucleotide polymorphisms (SNPs) in 14 genes predisposing to chronic glomerular diseases and IgAN in Han males, the 23 SNPs genotypes of 21 Han males were detected and analyzed with a BaiO gene chip, and their associations were analyzed with univariate analysis and multiple linear regression analysis. Analysis showed that CTLA4 rs231726 and CR2 rs1048971 revealed a significant association with IgAN. These findings support the multi-gene nature of the etiology of IgAN and propose a potential gene-gene interactive model for future studies.
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Superlubricity of two-dimensional fluorographene/MoS2 heterostructure: a first-principles study.
Nanotechnology
PUBLISHED: 09-02-2014
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The atomic-scale friction of the fluorographene (FG)/MoS2 heterostructure is investigated using first-principles calculations. Due to the intrinsic lattice mismatch and formation of periodic Moiré patterns, the potential energy surface of the FG/MoS2 heterostructure is ultrasmooth and the interlayer shear strength is reduced by nearly two orders of magnitude, compared with both FG/FG and MoS2/MoS2 bilayers, entering the superlubricity regime. The size dependency of superlubricity is revealed as being based on the relationship between the emergence of Moiré patterns and the lattice mismatch ratio for heterostructures.
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Strong type 1, but impaired type 2, immune responses contribute to Orientia tsutsugamushi-induced pathology in mice.
PLoS Negl Trop Dis
PUBLISHED: 09-01-2014
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Scrub typhus is a neglected, but important, tropical disease, which puts one-third of the world's population at risk. The disease is caused by Orientia tsutsugamushi, an obligately intracellular Gram-negative bacterium. Dysregulation in immune responses is known to contribute to disease pathogenesis; however, the nature and molecular basis of immune alterations are poorly defined. This study made use of a newly developed murine model of severe scrub typhus and focused on innate regulators and vascular growth factors in O. tsutsugamushi-infected liver, lungs and spleen. We found no activation or even reduction in base-line expression for multiple molecules (IL-7, IL-4, IL-13, GATA3, ROR-?t, and CXCL12) at 2, 6 and 10 days post-infection. This selective impairment in type 2-related immune responses correlated with a significant activation of the genes for IL-1?, IL-6, IL-10, TNF-?, IFN-?, as well as CXCR3- and CXCR1-related chemokines in inflamed tissues. The elevated angiopoietin (Ang)-2 expression and Ang-2/Ang-1 ratios suggested excessive inflammation and the loss of endothelial integrity. These alterations, together with extensive recruitment of myeloperoxidase (MPO)-expressing neutrophils and the influx of CD3+ T cells, contributed to acute tissue damage and animal death. This is the first report of selective alterations in a panel of immune regulators during early O. tsutsugamushi infection in intravenously inoculated C57BL/6 mice. Our findings shed new light on the pathogenic mechanisms associated with severe scrub typhus and suggest potential targets for therapeutic investigation.
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Plasmon-driven surface catalysis in hybridized plasmonic gap modes.
Sci Rep
PUBLISHED: 08-28-2014
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Plasmon-driven surface catalytic (PDSC) reaction in Ag/Au nanoparticle monomer or dimer-film gaps are experimentally and theoretically investigated, using surface enhanced Raman scattering (SERS) and finite element method. The variation of SERS spectra in different nano gaps of nanoparticle-film systems indicated the PDSC reaction was largely depended on the number of nanoparticles. The higher Raman intensity of p,p'-dimercaptoazobenzene (DMAB) in dimer-film nanogap was because effective coupling of induced image charge on metal film in hybridized plasmonic gap mode, which was confirmed by the electric field distribution. Furthermore, the influence of material and wavelength was also studied to obtain the optimal experimental condition for best surface catalysis in hybridized plasmonic gap mode. Our studies in this common configuration of plasmonic nanostructure are of great significance not only in the field of catalysis on metal surface but also in other surface plasmon fields such as senor, photon detection, water splitting, etc.
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Production of polyhydroxyalkanoates (PHA) by bacterial consortium from excess sludge fermentation liquid at laboratory and pilot scales.
Bioresour. Technol.
PUBLISHED: 08-20-2014
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The generation of polyhydroxyalkanoates (PHA) from excess sludge fermentation liquid (SFL) was studied at lab and pilot scale. A PHA-accumulated bacterial consortium (S-150) was isolated from activated sludge using simulated SFL (S-SFL) contained high concentration volatile fatty acids (VFA) and nitrogen. The maximal PHA content accounted for 59.18% in S-SFL and dropped to 23.47% in actual SFL (L-SFL) of the dry cell weight (DCW) at lab scale. The pilot-scale integrated system comprised an anaerobic fermentation reactor (AFR), a ceramic membrane system (CMS) and a PHA production bio-reactor (PHAR). The PHA content from pilot-scale SFL (P-SFL) finally reached to 59.47% DCW with the maximal PHA yield coefficient (YP/S) of 0.17 g PHA/g COD. The results indicated that VFA-containing SFL was suitable for PHA production. The adverse impact of excess nitrogen and non-VFAs in SFL might be eliminated by pilot-scale domestication, which might resulted in community structure optimization and substrate selective ability improvement of S-150.
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The critical role of UDP-galactose-4-epimerase in osteoarthritis: modulating proteoglycans synthesis of the articular chondrocytes.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-19-2014
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UDP-galactose-4-epimerase (GALE) is a key enzyme catalyzing the interconversion of UDP-glucose and UDP-galactose, as well as UDP-N-acetylglucosamine and UDP-N-acetylgalactosamine, which are all precursors for the proteoglycans (PGs) synthesis. However, whether GALE is essential in cartilage homeostasis remains unknown. Therefore, we investigated the role of GALE in PGs synthesis of human articular chondrocytes, the GALE expression in OA, and the regulation of GALE expression by interleukin-1beta (IL-1?). Silencing GALE gene with specific siRNAs resulted in a markedly inhibition of PGs synthesis in human articular chondrocytes. GALE protein levels were also decreased in both human and rat OA cartilage, thus leading to losses of PGs contents. Moreover, GALE mRNA expression was stimulated by IL-1? in early phase, but suppressed in late phase, while the suppression of GALE expression induced by IL-1? was mainly mediated by stress-activated protein kinase/c-Jun N-terminal kinase pathway. These data indicated a critical role of GALE in maintaining cartilage homeostasis, and suggested that GALE inhibition might contribute to OA progress.
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Adipose triglyceride lipase regulates lipid metabolism in dairy goat mammary epithelial cells.
Gene
PUBLISHED: 08-18-2014
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Adipose triglyceride lipase (ATGL) catalyzes the initial step in the lipid lipolysis process, hydrolyzing triglyceride (TG) to produce diacylglycerol (DG) and free fatty acids (FFA). In addition, ATGL regulates lipid storage and release in adipocyte cells. However, its role in mammary gland tissue remains unclear. To assess the role of the ATGL gene in the goat mammary gland, this study analyzed the tissue distribution and expression of key genes together with lipid accumulation after knockdown of the ATGL gene. The mRNA of ATGL was highly expressed in subcutaneous adipose tissue, the lung and the mammary gland with a significant increase in expression during the lactation period compared with the dry period of the mammary gland. Knockdown of the ATGL gene in goat mammary epithelial cells (GMECs) using siRNA resulted in a significant decrease in both ATGL mRNA and protein levels. Silencing of the ATGL gene markedly increased lipid droplet accumulation and intracellular TG concentration (P<0.05), while it reduced FFA levels in GMECs (P<0.05). Additionally, the expression of HSL for lipolysis, FABP3 for fatty acid transport, PPAR? for fatty acid oxidation, ADFP, BTN1A1, and XDH for milk fat formation and secretion was down-regulated (P<0.05) after knockdown of the ATGL gene, with increased expression of CD36 for fatty acid uptake (P<0.05). In conclusion, these data suggest that the ATGL gene plays an important role in triglyceride lipolysis in GMECs and provides the first experimental evidence that ATGL may be involved in lipid metabolism during lactation.
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Joint production of biodiesel and bioethanol from filamentous oleaginous microalgae Tribonema sp.
Bioresour. Technol.
PUBLISHED: 07-31-2014
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Making full use of lipid and carbohydrate in microalgae for joint production of biodiesel and bioethanol may create a potential way to cut the high cost of single biofuel production from microalgae. Compared with conventional unicellular oleaginous microalgae, filamentous microalgae Tribonema sp. is richer in lipid and carbohydrate contents and lower protein content, thus, this study explores the suitability of Tribonema sp. as a substrate for joint production of biodiesel and bioethanol. Acid hydrolysis is the key step to saccharify wall cell into fermentable sugar and release lipid. Microalgae biomass (50g/L) was acid (3% H2SO4) hydrolyzed at 121°C for 45min to reach the maximum hydrolysis efficiency (81.48%). Subsequently, the lipid separated with hexane-ethanol from the hydrolysate was converted into microalgae biodiesel and the conversion rate was 98.47%. With yeast Saccharomyces cerevisiae, the maximum ethanol yield of 56.1% was reached from 14.5g/L glucose in hydrolysate.
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Exchange Protein Directly Activated by cAMP (EPAC1) Modulates Regulatory T Cell-Mediated Immune Suppression.
Biochem. J.
PUBLISHED: 07-29-2014
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The cyclic adenosine monophosphate (cAMP) signaling pathway plays an essential role in immune functions. In this study we examined the role of the cAMP/EPAC1 (exchange protein directly activated by cAMP) axis in regulatory T-cell (Treg)-mediated immune suppression using genetic and pharmacologic approaches. Genetic deletion of EPAC1 in Treg and effector T-cells (Teff) synergistically attenuated Treg-mediated suppression of Teff. Mechanistically, EPAC1 inhibition enhanced activation of the transcription factor STAT3 and up-regulated SMAD7 expression while down-regulating expression of SMAD4. Consequently, CD4+T-cells were desensitized to TGF-?1, a cytokine employed by Treg cells to exert a broad inhibitory function within the immune system. Furthermore, deletion of EPAC1 led to production of significant levels of OVA-IgG antibodies in a low dose oral tolerance mouse mode. These in vivo observations are consistent with the finding that EPAC1 plays an important role in Treg-mediated suppression. More importantly, pharmacological inhibition of EPAC1 using an EPAC specific inhibitor recapitulates the EPAC1 deletion phenotype both in vivo and in vitro. Our results show that EPAC1 boosts Treg-mediated suppression, and identify EPAC1 as a target with broad therapeutic potential since Treg cells are involved in numerous pathologies including autoimmunity, infections, and a wide range of cancers.
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New uses for old drugs: the tale of artemisinin derivatives in the elimination of schistosomiasis japonica in China.
Molecules
PUBLISHED: 07-29-2014
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Artemisinin (qinghaosu), extracted from the Chinese herb Artemisia annua L. in 1972, and its three major derivatives--artemether, artesunate and dihydroartemisinin--were firstly identified as antimalarials and found active against all species of the malaria parasite. Since the early 1980s, artemisinin and its derivatives have been found efficacious against Schistosoma spp., notably larval parasites, and artemisinin derivatives have played a critical role in the prevention and treatment of human schistosomiasis in China. Currently, China is moving towards the progress of schistosomiasis elimination. However, the potential development of praziquantel resistance may pose a great threat to the progress of elimination of schistosomiasis japonica in China. Fortunately, these three major artemisinin derivatives also exhibit actions against adult parasites, and reduced sensitivity to artemether, artesunate and dihydroartemisinin has been detected in praziquantel-resistant S. japonicum. In this review, we describe the application of artemisinin derivatives in the prevention and treatment of schistosomiasis japonica in China, so as to provide tools for the global agenda of schistosomiasis elimination. In addition to antimalarial and antischistosomal actions, they also show activities against other parasites and multiple cancers. Artemisinin derivatives, as old drugs identified firstly as antimalarials, continue to create new stories.
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The Role of Kif4A in Doxorubicin-Induced Apoptosis in Breast Cancer Cells.
Mol. Cells
PUBLISHED: 07-28-2014
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This study was to investigate the mechanism and role of Kif4A in doxorubicin-induced apoptosis in breast cancer. Using two human breast cancer cell lines MCF-7 (with wild-type p53) and MDA-MB-231 (with mutant p53), we quantitated the expression levels of kinesin super-family protein 4A (Kif4A) and poly (ADP-ribose) Polymerase-1 (PARP-1) by Western blot after doxorubicin treatment and examined the apoptosis by flow cytometry after treatment with doxorubicin and PARP-1 inhibitor, 3-Aminobenzamide (3-ABA). Our results showed that doxorubicin treatment could induce the apoptosis of MCF-7 and MDA-MB-231 cells, the down-regulation of Kif4A and upregulation of poly(ADP-ribose) (PAR). The activity of PARP-1 or PARP-1 activation was significantly elevated by doxorubicin treatment in dose- and time-dependent manners (P < 0.05), while doxorubicin treatment only slightly elevated the level of cleaved fragments of PARP-1 (P > 0.05). We further demonstrated that overexpression of Kif4A could reduce the level of PAR and significantly increase apoptosis. The effect of doxorubicin on apoptosis was more profound in MCF-7 cells compared with MDA-MB-231 cells (P < 0.05). Taken together, our results suggest that the novel role of Kif4A in doxorubicin-induced apoptosis in breast cancer cells is achieved by inhibiting the activity of PARP-1.
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Smoking, MATRICS consensus cognitive battery and P50 sensory gating in a Han Chinese population.
Drug Alcohol Depend
PUBLISHED: 07-21-2014
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The effects of smoking on cognitive performance have long been studied, with mixed results. P50 sensory gating has been used as endophenotype for studying nicotinic systems genetics, and P50 gating deficits have been reported to be a sensitive biomarker for cognitive impairment in schizophrenia. This study examined the inter-relationship between P50 suppression, cognitive function, and smoking in a healthy Han Chinese population, which has not been reported before.
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Effects of background electrolytes and ionic strength on enrichment of Cd(II) ions with magnetic graphene oxide-supported sulfanilic acid.
J Colloid Interface Sci
PUBLISHED: 07-11-2014
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To elucidate the influence mechanisms of background electrolytes and ionic strength on Cd(II) removal, the adsorption of Cd(II) onto magnetic graphene oxide-supported sulfanilic acid (MGO-SA) in aqueous solutions containing different types and concentrations of background electrolytes was studied. The results indicate that Cd(II) adsorption was strongly dependent on pH and could be strongly affected by background electrolytes and ionic strength. The Cd(II) removal was decreased with the presence of background electrolyte cations (Na(+), K(+), Ca(2+), Mg(2+), Mn(2+), Zn(2+), and Ni(2+)), and the divalent cations exerted more obvious influences on the Cd(II) uptake than the monovalent cations at pH 6. Both Cl(-) and NO3(-) had negative effects on Cd(II) adsorption because they can form water-soluble metal-anion complexes with Cd(II) ions. The presence of 0.01molL(-1) Na3PO4 reduced the removal percentage of Cd(II) at pH<5 but extremely enhanced the Cd(II) removal when the pH>5. The Cd(II) adsorption was sensitive to changes in the concentration of NaCl, NaNO3, NaClO4, and Na3PO4. Besides, the adsorption isotherm of Cd(II) onto MGO-SA could be well described by the Freundlich model and was also influenced by the type of background electrolyte ions and the ionic strength.
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Tumor suppressor miR-1 restrains epithelial-mesenchymal transition and metastasis of colorectal carcinoma via the MAPK and PI3K/AKT pathway.
J Transl Med
PUBLISHED: 07-11-2014
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Aberrant expression of miR-1 has been implicated in various cancers. However, the mechanisms underlying the role of miR-1 in CRC progression still have not been clarified clearly. Here, we showed the decreased expression of miR-1 in colorectal carcinoma (CRC) tissues and cell lines. Ectopic introduction of miR-1 suppressed cell proliferation and migration, whereas miR-1 inhibitor performed contrary functions in CRC cells. Stable overexpression of miR-1 was sufficient to inhibit tumor growth and homing capacity in vivo. Proteomic analysis revealed that miR-1 modulated the expression of key cellular molecules and involved in the MAPK and PI3K/AKT pathways by inhibiting phosphorylation of ERK and AKT. Meanwhile, miR-1 also reversed epithelial¿mesenchymal transition (EMT), which played a pivotal role in the initiation of metastasis. Further studies found that miR-1 can target the 3' untranslated region (3'UTR) of LIM and SH3 protein 1 (LASP1) mRNA and suppress the expression of LASP1, identified as a CRC-associated protein. In contrast to the phenotypes induced by miR-1 restoration, LASP1-induced cell proliferation and migration partly rescued miR-1-mediated biological behaviors. Our results illustrated that miR-1 play a critical role in CRC progression, which suggests its potential role in the molecular therapy of cancer.
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Benzene solubility in ionic liquids: working toward an understanding of liquid clathrate formation.
Chemistry
PUBLISHED: 07-04-2014
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The solubility of benzene in 15 imidazolium, pyrrolidinium, pyridinium, and piperidinium ionic liquids has been determined; the resulting, benzene-saturated ionic liquid solutions, also known as liquid clathrates, were examined with (1) H and (19) F nuclear magnetic resonance spectroscopy to try and understand the molecular interactions that control liquid clathrate formation. The results suggest that benzene interacts primarily with the cation of the ionic liquid, and that liquid clathrate formation (and benzene solubility) is controlled by the strength of the cation-anion interactions, that is, the stronger the cation-anion interaction, the lower the benzene solubility. Other factors that were determined to be important in the final amount of benzene in any given liquid clathrate phase included attractive interactions between the anion and benzene (when significant), and larger steric or free volume demands of the ions, both of which lead to greater benzene solubility.
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Separation of polycarbonate and acrylonitrile-butadiene-styrene waste plastics by froth flotation combined with ammonia pretreatment.
Waste Manag
PUBLISHED: 07-04-2014
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The objective of this research is flotation separation of polycarbonate (PC) and acrylonitrile-butadiene-styrene (ABS) waste plastics combined with ammonia pretreatment. The PC and ABS plastics show similar hydrophobicity, and ammonia treatment changes selectively floatability of PC plastic while ABS is insensitive to ammonia treatment. The contact angle measurement indicates the dropping of flotation recovery of PC is ascribed to a decline of contact angle. X-ray photoelectron spectroscopy demonstrates reactions occur on PC surface, which makes PC surface more hydrophilic. Separation of PC and ABS waste plastics was conducted based on the flotation behavior of single plastic. At different temperatures, PC and ABS mixtures were separated efficiently through froth flotation with ammonia pretreatment for different time (13min at 23°C, 18min at 18°C and 30min at 23°C). For both PC and ABS, the purity and recovery is more than 95.31% and 95.35%, respectively; the purity of PC and ABS is up to 99.72% and 99.23%, respectively. PC and ABS mixtures with different particle sizes were separated effectively, implying that ammonia treatment possesses superior applicability.
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Molecularly Imprinted Photonic Polymers as Sensing Elements for the Creation of Cross-Reactive Sensor Arrays.
Chemistry
PUBLISHED: 06-24-2014
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By combining molecular imprinting and colloidal crystal templating, molecularly imprinted inverse-opal photonic polymers (MIPPs) acting as sensing elements have been exploited to create sensor arrays for the first time. With this new strategy, abundant sensing elements with differential sensing abilities were easily accessible. Because of the unique hierarchical porous structure integrated in each sensing element, high sensitivity and selectivity, fast response and self-reporting (label-free) detection could be simultaneously achieved. All these fascinating features indicate that MIPPs are ideal sensing elements for creating sensor arrays. By integrating the individual sensing elements on a substrate, the formed array chip delivers better portability and high-throughput capability. As a demonstration, six kinds of contaminants were selected as analytes. The detection and discrimination of these analytes and even their mixtures in a wide range of concentrations, particularly trace amounts of analyte against a high background of other components, could be achieved, indicating the powerful capability of MIPPs-based sensor array for sensing. These results suggest that the described strategy opens a new route for sensor array creation and should find important applications in a wide range of areas.
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Prenatal xenobiotic exposure and intrauterine hypothalamus-pituitary-adrenal axis programming alteration.
Toxicology
PUBLISHED: 06-24-2014
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The hypothalamic-pituitary-adrenal (HPA) axis is one of the most important neuroendocrine axes and plays an important role in stress defense responses before and after birth. Prenatal exposure to xenobiotics, including environmental toxins (such as smoke, sulfur dioxide and carbon monoxide), drugs (such as synthetic glucocorticoids), and foods and beverage categories (such as ethanol and caffeine), affects fetal development indirectly by changing the maternal status or damaging the placenta. Certain xenobiotics (such as caffeine, ethanol and dexamethasone) may also affect the fetus directly by crossing the placenta into the fetus due to their lipophilic properties and lower molecular weights. All of these factors probably result in intrauterine programming alteration of the HPA axis, which showed a low basal activity but hypersensitivity to chronic stress. These alterations will, therefore, increase the susceptibility to adult neuropsychiatric (such as depression and schizophrenia) and metabolic diseases (such as hypertension, diabetes and non-alcoholic fatty liver disease). The "over-exposure of fetuses to maternal glucocorticoids" may be the main initiation factor by which the fetal HPA axis programming is altered. Meantime, xenobiotics can directly induce abnormal epigenetic modifications and expression on the important fetal genes (such as hippocampal glucocorticoid receptor, adrenal steroidogenic acute regulatory protein, et al) or damage by in situ oxidative metabolism of fetal adrenals, which may also be contributed to the programming alteration of fetal HPA axis.
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Recombinant expression of glpK and glpD genes improves the accumulation of shikimic acid in E. coli grown on glycerol.
World J. Microbiol. Biotechnol.
PUBLISHED: 06-22-2014
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Shikimic acid (SA) is an industrially important chiral compound used in diverse commercial applications, and the insufficient supply by isolation from plants and expensive chemical synthesis of SA has increased the importance of developing strategies for SA synthesis. In our previous studies, glycerol was observed to be an effective carbon source for SA accumulation in E. coli DHPYAAS-T7, where the PTS operon (ptsHIcrr) and aroL and aroK genes were inactivated, and the tktA, glk, aroE, aroF (fbr) , and aroB genes were overexpressed. For further investigation of the effects of glycerol aerobic fermentation on SA accumulation in E. coli BL21(DE3), the glpD, glpK genes and tktA, glk, aroE, aroF (fbr) , aroB genes were overexpressed simultaneously. The results indicated that SA production was increased 5.6-fold, while the yield was increased 5.3-fold over that of parental strain in shake flasks. It is demonstrated that the aerobic fermentation of glycerol associated with glpD and glpK gene overexpression increased glycerol flux, resulting in higher SA accumulation in E. coli BL21(DE3)-P-DK.
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Visible-light driven degradation of ibuprofen using abundant metal-loaded BiVO4 photocatalysts.
Chemosphere
PUBLISHED: 06-16-2014
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An efficient method for the degradation of ibuprofen as an aqueous contaminant was developed under visible-light irradiation with as-prepared bismuth vanadate (BiVO4) catalysts. The metal-loaded catalysts Cu-BiVO4 and Ag-BiVO4 were synthesized using a hydrothermal process and then a wet-impregnation method. All of the materials were fully characterized by X-ray diffraction, scanning electron microscopy, UV-vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy and BET surface area. The results indicated that all of the prepared samples had monoclinic scheelite structures. In the metal-loaded catalysts, silver existed as a mixture of Ag and Ag2O on the surface of the catalysts. However, copper existed as Cu2O and CuO. Additionally, the band gap values of BiVO4, Ag-BiVO4, and Cu-BiVO4 were 2.38, 2.31, and 2.30eV, respectively. Compared to the BiVO4 catalyst, the metal-loaded BiVO4 catalysts showed superior photocatalytic properties for the degradation of ibuprofen.
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The inhibitory effect of angiotensin II on BKCa channels in podocytes via oxidative stress.
Mol. Cell. Biochem.
PUBLISHED: 06-13-2014
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Angiotensin II (Ang II) is an important active substance of the renin-angiotensin system (RAS). The present study has confirmed that abnormalities of Ang II may be related with cerebrovascular diseases, endocrine diseases, cardiovascular diseases, liver diseases, such as: cerebral hypoxia, diabetes, obesity, atrial fibrillation, and liver cirrhosis. However, understanding effects of Ang II on podocytes is not enough. This study was to investigate the effects of oxidative stress on the large conductance, Ca(2+)-activated K(+) channels (BKCa). Results from the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay showed that Ang II induced podocyte death in a concentration-dependent manner. The measurement of superoxide dismutase (SOD) generation demonstrated that Ang II decreased the total SOD of cellular levels. Meaningfully, pretreatment of a type of ROS scavenger formulations named N-(mercaptopropionyl)-glycine (N-MPG) could inhibit podocyte apoptosis induced by Ang II. Meanwhile, patch-clamp technique was used in this study to detect the effects of Ang II on currents of BKCa channel in podocytes. The results indicated that Ang II inhibited the current amplitude of BKCa channel and decreased the slope of I-V curve. Ang II also made the activation curves of BKCa channel shift to the left. These results may provide a theoretical basis for potential treatment of chronic glomerular disease in the future.
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Sensitive point-of-care monitoring of cardiac biomarker myoglobin using aptamer and ubiquitous personal glucose meter.
Biosens Bioelectron
PUBLISHED: 06-13-2014
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Myoglobin (Myo), which is one of the early markers to increase after acute myocardial infarction (AMI), plays a major role in urgent diagnosis of cardiovascular diseases. Hence, monitoring of Myo in point-of-care is fundamental. Here, a novel assay for sensitive and selective detection of Myo was introduced using a personal glucose meter (PGM) as readout. In the presence of Myo, the anti-Myo antibody immobilized on the surface of polystyrene microplate could capture the target Myo. Then the selected aptamer against Myo, which was obtained using our screening process, was conjugated with invertase, and such aptamer-invertase conjugates bound to the immobilized Myo due to the Myo/aptamer interaction. Subsequently, the resulting "antibody-Myo-aptamer sandwich" complex containing invertase conjugates hydrolyzed sucrose into glucose, thus establishing direct correlation between the Myo concentration and the amount of glucose measured by PGM. By employing the enzyme amplification, as low as 50pM Myo could be detected. This assay also showed high selectivity for Myo and was successfully used for Myo detection in serum samples. This work may provide a simple but reliable tool for early diagnosis of AMI in the world, especially in developing countries.
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Function of Global Regulator CodY in Bacillus thuringiensis BMB171 by Comparative Proteomic Analysis.
J. Microbiol. Biotechnol.
PUBLISHED: 06-12-2014
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CodY is a highly conserved protein in low G+C Gram-positive bacteria that regulates genes involved in sporulation and stationary-phase adaptation. Bacillus thuringiensis is a Gram-positive bacterium that forms spores and parasporal crystals during the stationary phase. To our knowledge, the regulatory mechanism of CodY in B. thuringiensis is unknown. To study the function of CodY protein in B. thuringiensis, BMB171codY- was constructed in a BMB171 strain. Shuttle vector containing ORF of cry1Ac10 was transformed into BMB171 and BMB171codY- called BMB171cry1Ac and BMB171codY-cry1Ac, respectively. Some morphological and physiological changes of codY mutant BMB171codY-cry1Ac were observed. A comparative proteomic analysis was conducted for both BMB171codY-cry1Ac and BMB171cry1Ac through two-dimensional gel electrophoresis and MALDI-TOF-MS/MS analysis. The results showed that the proteins regulated by CodY are involved in microbial metabolism, including branched chain amino acids metabolism, carbohydrate metabolism, fatty acid metabolism, and energy metabolism. Furthermore, we found CodY is involved in sporulation, biosynthesis of poly-?-hydroxybutyrate, growth, genetic competence, and translation. According to the analysis of differentially expressed proteins, and physiological characterization of the codY mutant, we performed bacterial one-hybrid and electrophoretic mobility shift assay experiments and confirmed the direct regulation of genes by CodY, specifically those involved in metabolism of branched chain amino acids, ribosomal recycling factor FRR, and the late competence protein ComER. Our data establish the foundation for in-depth study of regulation of CodY in B. thuringiensis, and also offer a potential biocatalyst for functions of CodY in other bacteria.
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Radiosynthesis and biological evaluation of a novel enoyl-ACP reductase inhibitor for Staphylococcus aureus.
Eur J Med Chem
PUBLISHED: 06-11-2014
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The pharmacokinetics (PK) and pharmacodynamics (PD) of PT119, a potent Staphylococcus aureus enoyl-ACP reductase (saFabI) inhibitor with a Ki value of 0.01 nM and a residence time of 750 min on the enzyme target, has been evaluated in mice. PT119 was found to have promising antibacterial activity in two different S. aureus infection models: it caused a 3 log reduction in the CFU's in a mouse thigh muscle infection model and increased the survival rate from 0% to 50% in a mouse systemic infection model. PT119 was then radiolabeled with carbon-11 to evaluate its biodistribution and PK in both healthy and S. aureus infected mice using positron emission tomography (PET). The biodistribution of [(11)C]PT119 and/or its labeled metabolites did not differ significantly between the healthy group and the infected group, and PT119 was found to distribute equally between serum and tissue during the ?1 h of analysis permitted by the carbon-11 half life. This approach provides important data for PK/PD modeling and is the first step in identifying radiotracers that can non-invasively image bacterial infection in vivo.
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Distinct temperature sensitivity of soil carbon decomposition in forest organic layer and mineral soil.
Sci Rep
PUBLISHED: 06-05-2014
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The roles of substrate availability and quality in determining temperature sensitivity (Q10) of soil carbon (C) decomposition are still unclear, which limits our ability to predict how soil C storage and cycling would respond to climate change. Here we determined Q10 in surface organic layer and subsurface mineral soil along an elevation gradient in a temperate forest ecosystem. Q10 was calculated by comparing the times required to respire a given amount of soil C at 15 and 25°C in a 350-day incubation. Results indicated that Q10 of the organic layer was 0.22-0.71 (absolute difference) higher than Q10 of the mineral soil. Q10 in both the organic layer (2.5-3.4) and the mineral soil (2.1-2.8) increased with decreasing substrate quality during the incubation. This enhancement of Q10 over incubation time in both layers suggested that Q10 of more labile C was lower than that of more recalcitrant C, consistent with the Arrhenius kinetics. No clear trend of Q10 was found along the elevation gradient. Because the soil organic C pool of the organic layer in temperate forests is large, its higher temperature sensitivity highlights its importance in C cycling under global warming.
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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.