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Find video protocols related to scientific articles indexed in Pubmed.
Synthesis and properties of greenish-blue-emitting iridium dendrimers with N-phenylcarbazole-based polyether dendrons by a post-dendronization route.
Dalton Trans
PUBLISHED: 11-20-2014
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A series of solution processible greenish-blue-emitting Ir dendrimers with polyether dendrons that consist of N-phenylcarbazole (NPC) are developed via a convenient post-dendronization method. It involves two steps: (i) the successful preparation of a reactive Ir core, namely m-HO-dfppyIr, only when the hydroxyl group is located at the meta position relative to the N atom in the C^N ligand so as to eliminate the possible resonance structure between enol and keto; and (ii) the subsequent functionalization with NPC-based polyether dendrons to afford the first, second and third generation Ir dendrimers (Ir-G1B, Ir-G2B and Ir-G3B) with ease and high yields over 60%. All these dendritic complexes possess good thermal stability with decomposition temperatures higher than 380 °C and glass transition temperatures higher than 200 °C. In addition, with the growing generation number, the intermolecular interactions between emissive Ir cores are expected to be effectively inhibited to avoid the luminescence quenching, which is confirmed from the blue-shifted emission peak and the enhanced lifetime of Ir-G3B in the solid state. As a result, on going from Ir-G1B to Ir-G3B, the maximum luminous efficiency rises upward from 4.7 to 9.2 cd A(-1) for nondoped electrophosphorescent devices. Further optimization by doping them into a dendritic H2 host leads to the improved luminous efficiencies as high as 20.0-25.2 cd A(-1).
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Resveratrol Attenuates Intermittent Hypoxia-Induced Macrophage Migration to Visceral White Adipose Tissue and Insulin Resistance in Male Mice.
Endocrinology
PUBLISHED: 11-19-2014
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Chronic intermittent hypoxia during sleep (IH), as occurs in sleep apnea, promotes systemic insulin resistance. Resveratrol (Resv) has been reported to ameliorate high-fat diet induced obesity, inflammation, and insulin resistance. To examine the effect of Resv on IH-induced metabolic dysfunction, male mice were subjected to IH or room air (RA) conditions for 8 weeks, and treated with either Resv or vehicle (Veh). Fasting plasma levels of glucose, insulin, and leptin were obtained, HOMA levels were calculated, and insulin sensitivity tests (phosphorylated AKT/total AKT) were performed in 2 visceral white adipose tissue (VWAT) depots (epididymal (Epi) and mesenteric (Mes)) along with FACS assessments for VWAT macrophages and phenotypes (M1 and M2). IH-Veh and IH-Resv mice showed initial reductions in food intake with later recovery, with resultant lower body weights after 8 weeks, but with IH-Resv showing better increases in body weight vs. IH-Veh. IH-Veh and IH-Resv mice exhibited lower fasting glucose levels, but only IH-Veh had increased HOMA vs. all 3 other groups. Leptin levels were preserved in IH-Veh but were significantly lower in IH-Resv. Reduced VWAT p-AKT/AKT responses to insulin emerged in both Mes and Epi in IH-Veh but normalized in IH-Resv. Increases total macrophage counts and in M1:M2 ratios occurred in IH-Veh Mes and Epi compared all other 3 groups. Thus, resveratrol ameliorates food intake and weight gain during IH exposures, and markedly attenuates VWAT inflammation and insulin resistance, thereby providing a potentially useful adjunctive therapy for metabolic morbidity in the context of sleep apnea.
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Multifunctional optical correlator for picosecond ultraviolet laser pulse measurement.
Appl Opt
PUBLISHED: 11-18-2014
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A compact multifunctional optical correlator system for pulse width measurement of ultrashort ultraviolet (UV) pulses has been designed and experimentally demonstrated. Both autocorrelation and cross-correlation functions are measured using a single nonlinear crystal, and the switching between two measurements requires no adjustment of phase matching and detector. The system can measure UV pulse widths from sub-picoseconds to 100 ps, and it involves no auxiliary pulse in the measurement. The measurement results on a burst-mode picosecond UV laser show a high-quality performance on speed, accuracy, resolution, and dynamic range. The proposed correlator can be applied to measure any ultrashort UV pulses produced through sum-frequency generation or second-harmonic generation.
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[Expressions of aquaporin-4, matrix metallo-proteinase-2 and matrix metallo-proteinase-14 in peritumor edematous zone of glioma and clinical implications].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 11-14-2014
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To distinguish the expressions of matrix metallo-poteinase and aquaporin in peritumor edematous zone and normal brain tissue for different pathological levels of glioma and explore the relationship of glioma cell invasiveness and brain edema.
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Substituent-Controlled Selective Synthesis of N-Acyl 2-Aminothiazoles by Intramolecular Zwitterion-Mediated C-N Bond Cleavage.
J. Org. Chem.
PUBLISHED: 11-12-2014
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The cleavage of C-N bonds is an interesting and challenging subject in modern organic synthesis. We have achieved the first zwitterion-controlled C-N bond cleavage in the MCR reaction among lithium alkynethiolates, bulky carbodiimides, and acid chlorides to construct N-acyl 2-aminothiazoles. This is a simple, highly efficient, and general method for the preparation of N-acyl 2-aminothiazoles with a broad range of substituents. The selective synthesis of N-acyl 2-aminothiazoles significantly depends on the steric hindrance of carbodiimides. The result is in striking contrast with our previous convergent reaction giving 5-acyl-2-iminothiazolines via 1,5-acyl migration. It is indeed interesting that the slight change of the substituents on the carbodiimides can completely switch the product structure. Experimental and theoretical results demonstrate the reason why the C-N bond cleavage in the present system is prior to the acyl migration. The intramolecular hydrogen relay via unprecedented Hofmann-type elimination is essential for this totally new zwitterion-controlled C-N bond cleavage.
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Facile Palladium-Catalyzed Hydrocarboxylation of Olefins without External CO Gas.
Org. Lett.
PUBLISHED: 11-07-2014
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An effective Pd-catalyzed hydrocarboxylation of olefins with phenyl formate and formic acid is described. A variety of carboxylic acids are obtained in good yields with high regioselectivities under operationally simple conditions without the use of toxic CO gas.
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Efficient synthesis of ?-extended phenazasilines for optical and electronic applications.
Chem. Commun. (Camb.)
PUBLISHED: 11-06-2014
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The rhodium-catalyzed synthesis of phenazasilines from readily achievable biarylhydrosilanes is presented. This highly efficient method offers opportunities for preparing ?-extended phenazasilines with enhanced optoelectronic properties for device applications in organic electronics.
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Vitreoscilla hemoglobin promotes Salecan production by Agrobacterium sp. ZX09.
J Zhejiang Univ Sci B
PUBLISHED: 11-05-2014
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Salecan is a novel exopolysaccharide produced by the strain Agrobacterium sp. ZX09, and it is composed of only glucose monomers. The unique chemical composition and excellent physicochemical properties make Salecan a promising material for applications in coagulation, lubrication, protection against acute liver injury, and alleviating constipation. In this study, we cloned the Vitreoscilla hemoglobin gene into a broad-host-range plasmid pCM158. Without antibiotic selection, there was negligible loss of the plasmid in the host Agrobacterium sp. ZX09 after one passage of cultivation. The expression of Vitreoscilla hemoglobin was demonstrated by carbon monoxide (CO) difference spectrum. The engineered strain Agrobacterium sp. ZX09 increased Salecan yield by 30%. The other physiological changes included its elevated respiration rate and cellular invertase activity.
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Chronic sleep fragmentation induces endothelial dysfunction and structural vascular changes in mice.
Sleep
PUBLISHED: 11-04-2014
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Sleep fragmentation (SF) is a common occurrence and constitutes a major characteristic of obstructive sleep apnea (OSA). SF has been implicated in multiple OSA-related morbidities, but it is unclear whether SF underlies any of the cardiovascular morbidities of OSA. We hypothesized that long-term SF exposures may lead to endothelial dysfunction and altered vessel wall structure.
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WDSPdb: a database for WD40-repeat proteins.
Nucleic Acids Res.
PUBLISHED: 10-29-2014
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WD40-repeat proteins, as one of the largest protein families, often serve as platforms to assemble functional complexes through the hotspot residues on their domain surfaces, and thus play vital roles in many biological processes. Consequently, it is highly required for researchers who study WD40 proteins and protein-protein interactions to obtain structural information of WD40 domains. Systematic identification of WD40-repeat proteins, including prediction of their secondary structures, tertiary structures and potential hotspot residues responsible for protein-protein interactions, may constitute a valuable resource upon this request. To achieve this goal, we developed a specialized database WDSPdb (http://wu.scbb.pkusz.edu.cn/wdsp/) to provide these details of WD40-repeat proteins based on our recently published method WDSP. The WDSPdb contains 63 211 WD40-repeat proteins identified from 3383 species, including most well-known model organisms. To better serve the community, we implemented a user-friendly interactive web interface to browse, search and download the secondary structures, 3D structure models and potential hotspot residues provided by WDSPdb.
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First Genome Sequence of Potential Mycotoxin-Degrading Bacterium Devosia nanyangense DDB001.
Genome Announc
PUBLISHED: 10-25-2014
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Devosia sp. nov. DDB001, isolated from mycotoxin-contaminated soil, is a potential mycotoxin-degrading alphaproteobacterium. To our knowledge, this is the first draft genome announcement of a Devosia species.
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Anti-inflammatory Diterpenoids from the Root Bark of Acanthopanax gracilistylus.
J. Nat. Prod.
PUBLISHED: 10-23-2014
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Five new ent-pimarane (1-3, 7, and 8) and three new ent-kaurane diterpenoids (4-6) and a new oleanane triterpene acid (9), together with 22 known compounds, were isolated from the root bark of the medicinal herb Acanthopanax gracilistylus. The structures of 1-9 were established based on the interpretation of high-resolution MS and 1D- and 2D-NMR data. The absolute configurations of 7 and 11 were determined by single-crystal X-ray diffraction and electronic circular dichroism analysis. Compounds 7 and 8 represent rare naturally occurring structures based on the devinyl ent-pimarane skeleton. Compounds 3, 10, 14, 16, and 17 exhibited potent inhibitory effects on the release of interleukin-1? (IL-1?), interleukin-8 (IL-8), and tumor necrosis factor (TNF-?) in lipopolysaccharide-stimulated peripheral blood mononuclear cells.
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[Protection of hypothermic preserved isolated rat hearts by resveratrol and its underlying mechanism].
Zhongguo Ying Yong Sheng Li Xue Za Zhi
PUBLISHED: 10-22-2014
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To investigate whether resveratrol (RES) plays a protective role in hypothermic preserved isolated rat hearts and whether it is mediated by regulation of silent information regulator protein-1 (Sirt-1) expression.
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Porous hollow Co3O4 with rhombic dodecahedral structures for high-performance supercapacitors.
Nanoscale
PUBLISHED: 10-21-2014
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Porous hollow Co3O4 with rhombic dodecahedral structures were prepared by the calcination of ZIF-67 ([Co(mim)2; mim = 2-methylimidazolate]) rhombic dodecahedral microcrystals. A supercapacitor was successfully constructed by adopting the resulting porous hollow Co3O4 rhombic dodecahedral structure as the electrode material, which showed a large specific capacitance of 1100 F g(-1) and retained more than 95.1% of the specific capacitance after 6000 continuous charge-discharge cycles. The excellent capacitive properties and stability mark the porous hollow Co3O4 with the rhombic dodecahedral structure as one of the most promising electrode materials for high-performance supercapacitors.
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Yolk-Shell Nanostructured Fe3O4@NiSiO3 for Selective Affinity and Magnetic Separation of His-Tagged Proteins.
ACS Appl Mater Interfaces
PUBLISHED: 10-21-2014
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Recent developments of nanotechnology encourage novel materials for facile separations and purifications of recombinant proteins, which are of great importance in disease diagnoses and treatments. We find that Fe3O4@NiSiO3 with yolk-shell nanostructure can be used to specifically purify histidine-tagged (His-tagged) proteins from mixtures of lysed cells with a recyclable process. Each individual nanoparticle composes by a mesoporous nickel silicate shell and a magnetic Fe3O4 core in the hollow inner, which is featured by its great loading efficiency and rapid response toward magnetic fields. The abundant Ni(2+) cations on the shell provide docking sites for selective coordination of histidine and the reversible release is induced by excess imidazole solution. Because of the Fe3O4 cores, the separation, concentration, and recycling of the nanocomposites become feasible under the controls of magnets. These characteristics would be highly beneficial in nanoparticle-based biomedical applications for targeted-drug delivery and biosensors.
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Lack of family-based association between common variations in WNK1 and blood pressure level.
Med. Sci. Monit.
PUBLISHED: 10-17-2014
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WNK1 (With No-lysine Kinase 1) modulates numerous sodium transport-related ion channels involved in regulation of blood pressure. Several studies have indicated associations between the common variants of the WNK1 gene and hypertension or blood pressure levels. However, little data exists on Asian populations and normotensive or pre-hypertensive subjects. Our aim was to detect whether the common variations in the WNK1 gene are potential contributors to individual variations in blood pressure in a family-based sample.
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Human connectome module pattern detection using a new multi-graph MinMax cut model.
Med Image Comput Comput Assist Interv
PUBLISHED: 10-17-2014
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Many recent scientific efforts have been devoted to constructing the human connectome using Diffusion Tensor Imaging (DTI) data for understanding the large-scale brain networks that underlie higher-level cognition in human. However, suitable computational network analysis tools are still lacking in human connectome research. To address this problem, we propose a novel multi-graph min-max cut model to detect the consistent network modules from the brain connectivity networks of all studied subjects. A new multi-graph MinMax cut model is introduced to solve this challenging computational neuroscience problem and the efficient optimization algorithm is derived. In the identified connectome module patterns, each network module shows similar connectivity patterns in all subjects, which potentially associate to specific brain functions shared by all subjects. We validate our method by analyzing the weighted fiber connectivity networks. The promising empirical results demonstrate the effectiveness of our method.
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A novel multiplexed fluorescence polarisation immunoassay based on a recombinant bi-specific single-chain diabody for simultaneous detection of fluoroquinolones and sulfonamides in milk.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess
PUBLISHED: 10-14-2014
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Major research efforts are focusing on the development of simultaneous multiplexed immunoassays. In this study, a novel dual-binding fluorescence polarisation immunoassay (DB-FPIA) using a broad-specificity bi-specific single-chain diabody (scDb) and two fluorescent-labelled tracers (sulfamethoxypyridazine-fluorescein isothiocyanate (SMP-FITC) and sarafloxacin-Texas Red (SAR-TR)) with different excitation and emission wavelengths was developed for simultaneous and high-throughput detection of 19 fluoroquinolones (FQs) and 13 sulfonamides (SAs) at the maximum residue limits in milk samples. Recoveries for spiked milk samples were from 76.4% to 128.4%, with a relative standard deviation lower than 13.9%. The developed DB-FPIA was then applied to field samples, followed by confirmation by LC-MS/MS. All three instances in which FQs and SAs were present at concentrations near or above the assay limit of detection were identified as positive by the developed DB-FPIA, demonstrating that the method is suitable for rapid screening of FQs and SAs contamination. The novel methodology combines the advantage of the FPIA and the broad sensitivity of scDb and shows great promise for fast multi-analyte screening of low-molecular weight chemical residues in food samples.
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Metal-organic frameworks and ?-cyclodextrin-based composite electrode for simultaneous quantification of guanine and adenine in a lab-on-valve manifold.
Analyst
PUBLISHED: 10-10-2014
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In this work, a novel chemically modified electrode is constructed based on metal-organic frameworks and ?-cyclodextrin (Cu3(BTC)2/?-CD, BTC = benzene-1,3,5-tricarboxylate) composite material. The electrode was used for simultaneous determination of guanine and adenine in a sequential injection lab-on-valve format and exhibited sensitive responses to guanine and adenine oxidation due to the ?-? stacking interaction of Cu3(BTC)2 and the inclusion behavior of ?-CD. The analytical performance was assessed with respect to the supporting electrolyte and its pH, accumulation time and accumulation potential, and the fluid flow rates. Under optimal conditions, linear calibration ranges for both guanine and adenine were from 1.0 × 10(-7) to 1.0 × 10(-5) mol L(-1), and detection limits (S/N = 3) were found to be 5.2 × 10(-8) and 2.8 × 10(-8) mol L(-1), respectively. The proposed sensor showed advantages of high sensitivity, simple sample preparation protocol, enhanced throughput and good reproducibility. Finally, the practical application of the proposed sensor has been performed for the determination of guanine and adenine in real samples with satisfactory results.
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The Relationship Between Disability-Adjusted Life Years of Cataracts and Ambient Erythemal Ultraviolet Radiation in China.
J Epidemiol
PUBLISHED: 09-30-2014
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Background: Cataracts are one of the major public health problems worldwide. Ultraviolet radiation (UVR) is one of the risk factors for cataract development. We analyzed the relationship between disability-adjusted life year (DALY) rates of cataracts and UVR exposure in China.Methods: DALY rates of cataracts and UVR exposure in 31 regions of China were calculated based on data from the Second China National Sample Survey on Disability and the United States' National Aeronautics and Space Administration database. The relationship between the DALY rates of cataracts and UVR was estimated by Spearman rank correlation analysis and linear regression analysis.Results: The elderly (?65 years) had higher DALY rates of cataracts than the whole population. The DALY rate of cataracts in the agricultural population was higher than that observed in the non-agricultural population. The DALY rates of cataracts were positively associated with UVR The DALY rates of cataracts in regions with higher UVR were higher than those in regions with lower UVR. An increase in the daily ambient erythemal UVR of 1000 J/m(2) was associated with an increase in the DALY rates of cataracts by 92 DALYs/100 000 (R(2) = 0.676) among the whole population, 34 DALYs/100 000 among the population <65 years old (R(2) = 0.423), 607 DALYs/100 000 among the population aged 65-74 years (R(2) = 0.617), and by 1342 DALYs/100 000 among the population ?75 years old (R(2) = 0.758).Conclusions: DALY rates of cataracts increased with increases in UVR exposure in 31 regions of China. Greater exposure to UVR increases the disease burden of cataracts in the whole population, especially in the elderly and among the agricultural population.
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[A virtual deformable mandible model used for reconstruction computer aided design of large mandibular defects].
Zhonghua Kou Qiang Yi Xue Za Zhi
PUBLISHED: 09-27-2014
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To establish a three- dimensional virtual deformable mandible model used for individual reconstruction design of large mandibular defect.
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Stepping in the direction of the fall: the next foot placement can be predicted from current upper body state in steady-state walking.
Biol. Lett.
PUBLISHED: 09-26-2014
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During human walking, perturbations to the upper body can be partly corrected by placing the foot appropriately on the next step. Here, we infer aspects of such foot placement dynamics using step-to-step variability over hundreds of steps of steady-state walking data. In particular, we infer dependence of the 'next' foot position on upper body state at different phases during the 'current' step. We show that a linear function of the hip position and velocity state (approximating the body center of mass state) during mid-stance explains over 80% of the next lateral foot position variance, consistent with (but not proving) lateral stabilization using foot placement. This linear function implies that a rightward pelvic deviation during a left stance results in a larger step width and smaller step length than average on the next foot placement. The absolute position on the treadmill does not add significant information about the next foot relative to current stance foot over that already available in the pelvis position and velocity. Such walking dynamics inference with steady-state data may allow diagnostics of stability and inform biomimetic exoskeleton or robot design.
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[Gene mining of sulfur-containing amino acid metabolic enzymes in soybean].
Yi Chuan
PUBLISHED: 09-25-2014
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The genes of sulfur-containing amino acid synthetases in soybean are essential for the synthesis of sulfur-containing amino acids. Gene mining of these enzymes is the basis for the molecular assistant breeding of high sulfur-containing amino acids in soybean. In this study, using software BioMercator2.1, 113 genes of sulfur-containing amino acid enzymes and 33 QTLs controlling the sulfur-containing amino acids content were mapped onto Consensus Map 4.0, which was integrated by genetic and physical maps of soybean. Sixteen candidate genes associated to the synthesis of sulfur-containing amino acids were screened based on the synteny between gene loci and QTLs, and the effect values of QTLs. Through a bioinformatic analysis of the copy number, SNP information, and expression profile of candidate genes, 12 related enzyme genes were identified and mapped on 8 linkage groups, such as D1a, M, A2, K, and G. The genes corresponding to QTL regions can explain 6%?38.5% genetic variation of sulfur-containing amino acids, and among them, the indirect effect values of 9 genes were more than 10%. These 12 genes were involved in sulfur-containing amino acid metabolism and were highly expressed in the cotyledons and flowers, showing an abundance of SNPs. These genes can be used as candidate genes for the development of functional markers, and it will lay a foundation for molecular design breeding in soybean.
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[Effect of matrine on NO and ADMA metabolism pathways in serum and tissues of mice with lipopolysaccharide-induced intestine tissue inflammation].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-24-2014
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To discuss the effect of matrine on nitric oxide (NO) and asymmetric methylarginine (ADMA) metabolism pathways in serum and tissues of mice with lipopolysaccharide (LPS) -induced intestine tissue inflammation.
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Transcriptomic changes during the pre-receptive to receptive transition in human endometrium detected by RNA-Seq.
J. Clin. Endocrinol. Metab.
PUBLISHED: 09-23-2014
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Context: Identifying novel molecular markers for assessing endometrial receptivity is necessary for understanding human implantation and may help in improving the clinical outcome of in vitro fertilization (IVF). Objective: We aimed to compare the gene expression profiles of the pre-receptive versus receptive phases of the natural cycle in human endometrial biopsies. Design: The design of this study was detecting the global gene expression profile of human endometrial receptivity by RNA-Seq. Setting: This study was conducted at a university reproductive center. Participants: Twelve women with normal menstrual cycles. Intervention: Study interventions included endometrial biopsies. Main Outcome Measures: The endometrial transcriptomes were determined by RNA-Seq, and the expression of selected differentially expressed genes (DEGs) was validated by quantitative RT-PCR. Results: A total of 2372 DEGs were identified by RNA-Seq. Of these genes, 1099 were up-regulated at LH+7 versus LH+2, whereas 1273 were down-regulated. Nineteen selected genes were confirmed by quantitative RT-PCR. We first demonstrated that metallothionein (MT) family members, MT1E, F, G, H, M, X, and 2A, and four novel transcripts, HAP1, ZCCHC12, MRAP2 and OVGP1, which were not previously linked to endometrial physiology, showed significant expression changes during implantation. Mineral absorption was the most enriched pathway for up-regulated genes, and cell cycle was enriched for down-regulated genes. Gene co-expression network analysis identified 5 core regulatory factors (GLI2, CDC25A, TLR9, MT1G and SLC5A1) that are involved in endometrial receptivity during implantation. Examination of the promoter regions of the DEGs identified AP2 and SP1 binding sites, suggesting a potential regulatory role in endometrial gene expression for these two transcription factors. Conclusions: This study provides the first RNA-Seq-based transcriptome comparison of pre-receptive and receptive human endometria. Many novel candidate genes, which have not been previously studied in human endometrium, may have functional significance during implantation and serve as molecular markers for endometrial receptivity.
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Neurotrophic Factor Artemin Promotes Invasiveness and Neurotrophic Function of Pancreatic Adenocarcinoma in Vivo and in Vitro.
Pancreas
PUBLISHED: 09-23-2014
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The aim of this study was to investigate the effect of the neurotrophic factor Artemin on neuroplasticity and perineural invasion of pancreatic adenocarcinoma.
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Two new anxiolytic phenanthrenes found in the medullae of Juncus effusus.
Nat Prod Commun
PUBLISHED: 09-20-2014
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Six phenanthrenes, 2-methoxy-7-hydroxy-1-methyl-5-vinyl phenanthrene (1), juncusin (2), dehydroeffusol (3), juncusol (4), effusol (5), and dehydroeffusal (6), were isolated from the medullae of Juncus effusus L. Compounds 1 and 2 were identified as being new structures, and both of them showed anxiolytic activity at dosages of 10 and 2.5 mg/kg, respectively.
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Requirement for ssbp2 in hematopoietic stem cell maintenance and stress response.
J. Immunol.
PUBLISHED: 09-19-2014
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Transcriptional mechanisms governing hematopoietic stem cell (HSC) quiescence, self-renewal, and differentiation are not fully understood. Sequence-specific ssDNA-binding protein 2 (SSBP2) is a candidate acute myelogenous leukemia (AML) suppressor gene located at chromosome 5q14. SSBP2 binds the transcriptional adaptor protein Lim domain-binding protein 1 (LDB1) and enhances LDB1 stability to regulate gene expression. Notably, Ldb1 is essential for HSC specification during early development and maintenance in adults. We previously reported shortened lifespan and greater susceptibility to B cell lymphomas and carcinomas in Ssbp2(-/-) mice. However, whether Ssbp2 plays a regulatory role in normal HSC function and leukemogenesis is unknown. In this study, we provide several lines of evidence to demonstrate a requirement for Ssbp2 in the function and transcriptional program of hematopoietic stem and progenitor cells (HSPCs) in vivo. We found that hematopoietic tissues were hypoplastic in Ssbp2(-/-) mice, and the frequency of lymphoid-primed multipotent progenitor cells in bone marrow was reduced. Other significant features of these mice were delayed recovery from 5-fluorouracil treatment and diminished multilineage reconstitution in lethally irradiated bone marrow recipients. Dramatic reduction of Notch1 transcripts and increased expression of transcripts encoding the transcription factor E2a and its downstream target Cdkn1a also distinguished Ssbp2(-/-) HSPCs from wild-type HSPCs. Finally, a tendency toward coordinated expression of SSBP2 and the AML suppressor NOTCH1 in a subset of the Cancer Genome Atlas AML cases suggested a role for SSBP2 in AML pathogenesis. Collectively, our results uncovered a critical regulatory function for SSBP2 in HSPC gene expression and function.
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Enhanced normal-direction excitation and emission of dual-emitting quantum dots on a cascaded photonic crystal surface.
Nanoscale
PUBLISHED: 09-19-2014
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Large normal-direction excitation and emission of dual-emitting quantum dots (QDs) are essential for practical application of QD sensors based on the ratiometric fluorescence response. We have numerically demonstrated an all-dielectric four-layer cascaded photonic crystal (CPC) structure (alternating TiO2 and SiO2/SU8 layers with two dimensional nanoscale patterns in each layer) which is capable of providing normal-direction high Q-factor leaky modes at excitation wavelengths of QDs and two low Q-factor leaky modes coinciding with the two emission peaks of a dual-emitting QD. Normal-direction excitation and far-field emission of the dual-emitting QDs are enhanced significantly when QDs are distributed on/in the top TiO2 layer of the CPC structure, especially in the spatial distribution areas of the resonant leaky modes. QDs can be positioned differently depending on the applications. Positioning QDs on the top TiO2 layer will improve the signal-to-noise ratios of QD biomedical/chemical/temperature sensors, while embedding QDs in the top TiO2 layer will increase the light extraction from the QD light emitting device, making our CPC a versatile optical coupling structure. Our CPC-QD structure is experimentally feasible and robust against the parameter perturbation in real fabrication.
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Inhibiting the Th17/IL-17A-Related Inflammatory Responses With Digoxin Confers Protection Against Experimental Abdominal Aortic Aneurysm.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 09-18-2014
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T helper 17 cells and interleukin-17A have been implicated in the progression of abdominal aortic aneurysm (AAA). Retinoic acid-related orphan receptor gamma thymus, the master transcription factor of T helper 17 cell differentiation, is selectively antagonized by digoxin. However, the effect of antagonizing retinoic acid-related orphan receptor gamma thymus on AAA has not been investigated.
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Hybrid balloon valvuloplasty through the ascending aorta via median sternotomy in infants with severe congenital valvular aortic stenosis: feasibility of a new method†
Eur J Cardiothorac Surg
PUBLISHED: 09-18-2014
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To evaluate a novel hybrid balloon valvuloplasty procedure for severe congenital valvular aortic stenosis in low-weight infants, performed through the ascending aorta via median sternotomy.
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Alkali and alkaline earth metallic (AAEM) species leaching and Cu(II) sorption by biochar.
Chemosphere
PUBLISHED: 09-03-2014
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Alkali and alkaline earth metallic (AAEM) species water leaching and Cu(II) sorption by biochar prepared from two invasive plants, Spartina alterniflora (SA) and water hyacinth (WH), were explored in this work. Significant amounts of Na and K can be released (maximum leaching for Na 59.0mgg(-1) and K 79.9mgg(-1)) from SA and WH biochar when they are exposed to contact with water. Cu(II) removal by biochar is highly related with pyrolysis temperature and environmental pH with 600-700°C and pH of 6 showing best performance (29.4 and 28.2mgg(-1) for SA and WH biochar). Cu(II) sorption exerts negligible influence on Na/K/Mg leaching but clearly promotes the release of Ca. Biochars from these two plant species provide multiple benefits, including nutrient release (K), heavy metal immobilization as well as promoting the aggregation of soil particles (Ca) for soil amelioration. AAEM and Cu(II) equilibrium concentrations in sorption were analyzed by positive matrix factorization (PMF) to examine the factors underlying the leaching and sorption behavior of biochar. The identified factors can provide insightful understanding on experimental phenomena.
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Like or dislike? Affective preference modulates neural response to others' gains and losses.
PLoS ONE
PUBLISHED: 08-29-2014
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Previous studies have demonstrated that the brain responds differentially to others' gains and losses relative to one's own, moderated by social context factors such as competition and interpersonal relationships. In the current study, we tested the hypothesis that the neural response to others' outcomes could be modulated by a short-term induced affective preference. We engaged 17 men and 18 women in a social-exchange game, in which two confederates played fairly or unfairly. Both men and women rated the fair player as likable and the unfair players as unlikable. Afterwards, ERPs were recorded while participants observed each confederates playing a gambling game individually. This study examines feedback related negativity (FRN), an ERP component sensitive to negative feedback. ANOVA showed a significant interaction in which females but not males displayed stronger FRNs when observing likable players' outcomes compared to unlikable ones'. However, males did not respond differently under either circumstance. These findings suggest that, at least in females, the neural response is influenced by a short-term induced affective preference.
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Long noncoding RNA HOTAIR involvement in cancer.
Tumour Biol.
PUBLISHED: 08-29-2014
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Evidences have been provided that long noncoding RNAs (lncRNAs) act as key molecules in epigenetic regulation and are involved in the development process of cancer in recent studies. HOX transcript antisense RNA (HOTAIR), a long intergenic noncoding RNA (lincRNA), functions as a molecular scaffold to link and target two histone modification complexes PRC2 and LSD1, then reprograms chromatin states by couples histone H3K27 methylation and H3K4 demethylation for epigenetic gene silencing to promote cancer metastasis. HOTAIR, regarded as an oncogene, is pervasively overexpressed in most solid cancers and correlated with tumor invasion, progression, metastasis, and poor prognosis, and HOTAIR has been proven to play a critical role in most biological process of cancer and would be a potential new target in cancer therapy.
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Complete genome sequence of Bifidobacterium animalis RH, a probiotic bacterium producing exopolysaccharides.
J. Biotechnol.
PUBLISHED: 08-25-2014
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Bifidobacterium animalis RH is a probiotic bacterium producing exopolysaccharides, which was isolated from the feces of Bama centenarians in Guangxi, China. The genome consists of one chromosome (1,931,057bp) with no plasmid. The genomic sequence indicated that this strain includes a gene cluster involved in exopolysaccharides (EPS) biosynthesis. Genome sequencing information provides the basis for analysis of molecular mechanisms responsible for regulation of production of EPS.
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Proteomic investigation into betulinic acid-induced apoptosis of human cervical cancer HeLa cells.
PLoS ONE
PUBLISHED: 08-22-2014
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Betulinic acid is a pentacyclic triterpenoid that exhibits anticancer functions in human cancer cells. This study provides evidence that betulinic acid is highly effective against the human cervical cancer cell line HeLa by inducing dose- and time-dependent apoptosis. The apoptotic process was further investigated using a proteomics approach to reveal protein expression changes in HeLa cells following betulinic acid treatment. Proteomic analysis revealed that there were six up- and thirty down-regulated proteins in betulinic acid-induced HeLa cells, and these proteins were then subjected to functional pathway analysis using multiple analysis software. UDP-glucose 6-dehydrogenase, 6-phosphogluconate dehydrogenase decarboxylating, chain A Horf6-a novel human peroxidase enzyme that involved in redox process, was found to be down-regulated during the apoptosis process of the oxidative stress response pathway. Consistent with our results at the protein level, an increase in intracellular reactive oxygen species was observed in betulinic acid-treated cells. The proteins glucose-regulated protein and cargo-selection protein TIP47, which are involved in the endoplasmic reticulum pathway, were up-regulated by betulinic acid treatment. Meanwhile, 14-3-3 family proteins, including 14-3-3? and 14-3-3?, were down-regulated in response to betulinic acid treatment, which is consistent with the decrease in expression of the target genes 14-3-3? and 14-3-3?. Furthermore, it was found that the antiapoptotic bcl-2 gene was down-regulated while the proapoptotic bax gene was up-regulated after betulinic acid treatment in HeLa cells. These results suggest that betulinic acid induces apoptosis of HeLa cells by triggering both the endoplasmic reticulum pathway and the ROS-mediated mitochondrial pathway.
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The Sch9 kinase regulates conidium size, stress responses, and pathogenesis in Fusarium graminearum.
PLoS ONE
PUBLISHED: 08-21-2014
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Fusarium head blight caused by Fusarium graminearum is an important disease of wheat and barley worldwide. In a previous study on functional characterization of the F. graminearum kinome, one protein kinase gene important for virulence is orthologous to SCH9 that is functionally related to the cAMP-PKA and TOR pathways in the budding yeast. In this study, we further characterized the functions of FgSCH9 in F. graminearum and its ortholog in Magnaporthe oryzae. The ?Fgsch9 mutant was slightly reduced in growth rate but significantly reduced in conidiation, DON production, and virulence on wheat heads and corn silks. It had increased tolerance to elevated temperatures but became hypersensitive to oxidative, hyperosmotic, cell wall, and membrane stresses. The ?Fgsch9 deletion also had conidium morphology defects and produced smaller conidia. These results suggest that FgSCH9 is important for stress responses, DON production, conidiogenesis, and pathogenesis in F. graminearum. In the rice blast fungus Magnaporthe oryzae, the ?Mosch9 mutant also was defective in conidiogenesis and pathogenesis. Interestingly, it also produced smaller conidia and appressoria. Taken together, our data indicate that the SCH9 kinase gene may have a conserved role in regulating conidium size and plant infection in phytopathogenic ascomycetes.
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[Effect of UCP2-siRNA on inflammatory response of cardiomyocytes induced by septic serum].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 08-21-2014
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To study the effect of uncoupling protein 2 (UCP2)-siRNA on the inflammatory response of rat cardiomyocytes (H9C2) induced by septic serum and to investigate the possible role of UCP2 in the development of septic cardiomyopathy.
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Silver-catalysed direct amination of unactivated C-H bonds of functionalized molecules.
Nat Commun
PUBLISHED: 08-20-2014
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Carbon-nitrogen bond formation from inert C-H bonds is an ideal organic transformation and a highly desirable method for the synthesis of N-containing molecules due to its high efficiency and atom economy. In this report, we develop a general reaction to achieve an unprecedented selective intramolecular amination of unactivated C-H bond in the absence of complex directing groups. Functionalized heterocyclic products are built up from readily available linear amines through simple and reliable silver catalysis, representing a new silver-based C-H functionalization. This method displays preference for primary sp(3) C-H bonds and exhibits distinct chemo- and regioselectivity compared to existing methods of direct amination (Hofmann-Löffler-Freytag reaction and nitrene insertion). The study highlights the manipulation of unfunctionalized groups in organic molecules to furnish complex structural units in the natural and bioactive molecules.
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Long-term ultrasound biomicroscopy observation of position changes of a copolymer posterior chamber phakic intraocular lens.
J Cataract Refract Surg
PUBLISHED: 08-20-2014
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To evaluate longitudinal changes in Implantable Collamer Lens phakic intraocular lens (pIOL) position after implantation.
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IL-6/STAT3 promotes regeneration of airway ciliated cells from basal stem cells.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 08-18-2014
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The pseudostratified airway epithelium of the lung contains a balanced proportion of multiciliated and secretory luminal cells that are maintained and regenerated by a population of basal stem cells. However, little is known about how these processes are modulated in vivo, and about the potential role of cytokine signaling between stem and progenitor cells and their niche. Using a clonal 3D organoid assay, we found that IL-6 stimulated, and Stat3 inhibitors reduced, the generation of ciliated vs. secretory cells from basal cells. Gain-of-function and loss-of-function studies with cultured mouse and human basal cells suggest that IL-6/Stat3 signaling promotes ciliogenesis at multiple levels, including increases in multicilin gene and forkhead box protein J1 expression and inhibition of the Notch pathway. To test the role of IL-6 in vivo genetically, we followed the regeneration of mouse tracheal epithelium after ablation of luminal cells by inhaled SO2. Stat3 is activated in basal cells and their daughters early in the repair process, correlating with an increase in Il-6 expression in platelet-derived growth factor receptor alpha(+) mesenchymal cells in the stroma. Conditional deletion in basal cells of suppressor of cytokine signaling 3, encoding a negative regulator of the Stat3 pathway, results in an increase in multiciliated cells at the expense of secretory and basal cells. By contrast, Il-6 null mice regenerate fewer ciliated cells and an increased number of secretory cells after injury. The results support a model in which IL-6, produced in the reparative niche, functions to enhance the differentiation of basal cells, and thereby acts as a "friend" to promote airway repair rather than a "foe."
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Up-Regulation of c-Fos Associated with Neuronal Apoptosis Following Intracerebral Hemorrhage.
Cell. Mol. Neurobiol.
PUBLISHED: 08-17-2014
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The proto-oncogene c-Fos is an important member of the activating protein 1 (AP-1) transcription complex involved in major cellular functions such as transformation, proliferation, differentiation, and apoptosis. The expression of c-Fos is very tightly regulated and responses rapidly and transiently to a plethora of apoptotic stimuli. However, it is still unclear how c-Fos functions on neuronal activities following intracerebral hemorrhage (ICH). In the present studies, we uncovered that the up-regulation of c-Fos is related to neuronal apoptosis following ICH probably via FasL/Fas apoptotic pathway. From the results of Western blot and immunohistochemistry, we obtained that c-Fos is significantly up-regulated surrounding the hematoma following ICH and co-locates with active caspase-3 in the neurons. Besides, electrophoretic mobility shift assay exhibits high AP-1 DNA-binding activities in ICH groups due to the increase of c-Fos expression. In addition, there are concomitant up-regulation of Fas ligand (FasL), which is the target protein of AP-1, Fas, active caspase-8, and active caspase-3 in vivo and in vitro studies. What is more, our in vitro study showed that using c-Fos-specific RNA interference in primary cortical neurons, the expression of FasL and active caspase-3 are suppressed. Thus, our results indicated that c-Fos might exert its pro-apoptotic function on neuronal apoptosis following ICH.
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SOX2 promotes tumorigenicity and inhibits the differentiation of I-type neuroblastoma cells.
Int. J. Oncol.
PUBLISHED: 08-09-2014
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SOX2 is a transcription factor associated with the pluripotency, proliferative potential, and self-renewing properties observed with embryonic stem cells and germ cells. SOX2 expression has been reported in several cancers and is implicated in tumorigenesis. We previously found that SOX2 expression was correlated to the clinical stage of neuroblastoma. Recently, we found that SOX2 overexpression occurs in I-type neuroblastoma cells (BE(2)-C cells). To elucidate the tumorigenic function of SOX2, we established a SOX2 overexpressed BE(2)-C cell line. SOX2 overexpressed cells showed higher tumorigenicity than control cells and exhibited decreased expression levels of marker proteins of N- or S-type cells after agent-induced differetiation. By contrast, in cells where SOX2 mRNA expression was knocked down by gene-specific siRNA, tumorigenicty was significantly decreased and the expression levels of marker proteins of N- or S-type cells were upregulated. In conclusion, our findings indicate an important function for SOX2 in promoting tumorigenicity of I-type neuroblastoma cells and in inhibiting their differentiation, suggesting that SOX2 might be a potential therapeutic target in neuroblastoma.
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Gait characteristic analysis and identification based on the iPhone's accelerometer and gyrometer.
Sensors (Basel)
PUBLISHED: 08-07-2014
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Gait identification is a valuable approach to identify humans at a distance. In this paper, gait characteristics are analyzed based on an iPhone's accelerometer and gyrometer,and a new approach is proposed for gait identification. Specifically, gait datasets are collected by the triaxial accelerometer and gyrometer embedded in an iPhone. Then, the datasets are processed to extract gait characteristic parameters which include gait frequency, symmetry coefficient, dynamic range and similarity coefficient of characteristic curves. Finally, a weighted voting scheme dependent upon the gait characteristic parameters is proposed forgait identification. Four experiments are implemented to validate the proposed scheme. The attitude and acceleration solutions are verified by simulation. Then the gait characteristics are analyzed by comparing two sets of actual data, and the performance of the weighted voting identification scheme is verified by 40 datasets of 10 subjects.
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The expression of epithelial-mesenchymal transition-related proteins in biliary epithelial cells is associated with liver fibrosis in biliary atresia.
Pediatr. Res.
PUBLISHED: 08-05-2014
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BackgroundThe epithelial-mesenchymal transition (EMT) has been implicated as a key mechanism in the pathogenesis of liver fibrosis. The miR-200 family has been shown to inhibit EMT.MethodsLiver fibrosis levels were assessed with Masson's trichrome staining of liver samples obtained from biliary atresia (BA) patients.The expressions of cytokeratin-7 (CK-7) and alpha-smooth muscle actin (a-SMA) in the liver sections were detected by immunohistochemical and immunofluorescent staining. EMTs were induced by transforming growth factor (TGF)-?1 in human biliary epithelial cells (BECs) in vitro.ResultsWe showed that the EMT-related proteins CK-7 and a-SMA co-localised to the intrahepatic BECs in the liver sections of patients with BA. The level of a-SMA expression was related to liver fibrosis stage in BA. EMT in primary human intrahepatic BECs was induced by TGF-?1 in vitro. miR-200b is one member of the miR-200 family and significantly inhibited TGF-?1-mediated EMT in BECs.ConclusionTogether, these data suggest that the occurrence of EMT in BECs might contribute to BA fibrosis. miR-200b significantly affects the development and progression of TGF-?1-dependent EMT and fibrosis in vitro.Pediatric Research (2014); doi:10.1038/pr.2014.181.
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Coordinated control of slip ratio for wheeled mobile robots climbing loose sloped terrain.
ScientificWorldJournal
PUBLISHED: 07-25-2014
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A challenging problem faced by wheeled mobile robots (WMRs) such as planetary rovers traversing loose sloped terrain is the inevitable longitudinal slip suffered by the wheels, which often leads to their deviation from the predetermined trajectory, reduced drive efficiency, and possible failures. This study investigates this problem using terramechanics analysis of the wheel-soil interaction. First, a slope-based wheel-soil interaction terramechanics model is built, and an online slip coordinated algorithm is designed based on the goal of optimal drive efficiency. An equation of state is established using the coordinated slip as the desired input and the actual slip as a state variable. To improve the robustness and adaptability of the control system, an adaptive neural network is designed. Analytical results and those of a simulation using Vortex demonstrate the significantly improved mobile performance of the WMR using the proposed control system.
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Traditional Chinese medicine for stable angina pectoris via TCM pattern differentiation and TCM mechanism: study protocol of a randomized controlled trial.
Trials
PUBLISHED: 07-24-2014
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Stable angina pectoris is experienced as trans-sternal or retro-sternal pressure or pain that may radiate to the left arm, neck or back. Although available evidence relating to its effectiveness and mechanism are weak, traditional Chinese medicine is used as an alternative therapy for stable angina pectoris. We report a protocol of a randomized controlled trial using traditional Chinese medicine to investigate the effectiveness, mechanism and safety for patients with stable angina pectoris.
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Antidepressant-like effects of Chaihu-Shugan-San via SAPK/JNK signal transduction in rat models of depression.
Pharmacogn Mag
PUBLISHED: 07-24-2014
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Chaihu-Shugan-San (CHSGS), a traditional Chinese medicinal herbal formula, registered in Jingyue Quanshu, has been indicated that oral administration of the extract from it can remit depressive disorder. C-Jun amino-terminal kinase (JNK/SAPK) signal transduction plays a key role in the apoptosis of nerve cells, be reported closely correlated with depression. This study was designed to investigate CHSGS antidepressant-like effects in rat models of depression and probe its possible mechanism.
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Selective capture of transcribed sequences in the functional gene analysis of microbial pathogens.
Appl. Microbiol. Biotechnol.
PUBLISHED: 07-22-2014
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Selective capture of transcribed sequences (SCOTS) is an effective method to identify bacterial genes differentially expressed during different biological processes, including pathogenic interactions with a host species. The method can be used to elucidate molecular mechanisms driving and maintaining such interactions. The method is a powerful genetic tool that overcomes limitations found in other methods, by working with small amounts of mRNA and allowing for the separation of bacterial cDNA from host cDNA. It has been increasingly used in the discovery of genes involved in the bacterium-host interaction. In this review, we briefly introduce the SCOTS method, outline the technical advances offered in the method, and focus on the method's applications in several microbial pathogens.
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Human urine-derived stem cells in combination with polycaprolactone/gelatin nanofibrous membranes enhance wound healing by promoting angiogenesis.
J Transl Med
PUBLISHED: 07-22-2014
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BackgroundDespite advancements in wound healing techniques and devices, new treatments are needed to improve therapeutic outcomes. This study aimed to evaluate the potential use of a new biomaterial engineered from human urine-derived stem cells (USCs) and polycaprolactone/gelatin (PCL/GT) for wound healing.MethodsUSCs were isolated from healthy individuals. To fabricate PCL/GT composite meshes, twin-nozzle electrospinning were used to spin the PCL and gelatin solutions in normal organic solvents. The morphologies and hydrophilicity properties of PCL/GT membranes were investigated. After USCs were seeded onto a PCL/GT, cell adhesion, morphology, proliferation, and cytotoxicity were examined. Then, USCs were seeded on a PCL/GT blend nanofibrous membrane and transplanted into rabbit full-thickness skin defects for wound repair. Finally, the effect of USCs condition medium on proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs) were performed in vitro.ResultsUSCs were successfully isolated from urine samples and expressed specific mesenchymal stem cells markers and could differentiate into osteoblasts, adipocytes, and chondrocytes. PCL/GT membrane has suitable mechanical properties similar with skin tissue and has good biocompatibility. USCs-PCL/GT significantly enhanced the healing of full-thickness skin wounds in rabbits compared to wounds treated with PCL/GT membrane alone or untreated wounds. USCs-PCL/GT-treated wounds closed much faster, with increased re-epithelialization, collagen formation, and angiogenesis. Moreover, USCs could secrete VEGF and TGF-ß1, and USC-conditioned medium enhanced the migration, proliferation, and tube formation of endothelial cells.ConclusionUSCs in combination with PCL/GT significantly prompted the healing of full-thickness skin wounds in rabbits. USCs based therapy provides a novel strategy for accelerating wound closure and promoting angiogenesis.
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Factors associated with spontaneous clearance of hepatitis C virus in Chinese population.
Biomed Res Int
PUBLISHED: 07-16-2014
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Hepatitis C virus (HCV) infections spontaneously clear in approximately 15-45% of infected individuals. Factors which influence spontaneous HCV clearance remain to be identified. The purpose of the present study was to identify variables associated with spontaneous HCV clearance in a referred population of Chinese patients. The prevalence of host, viral, and environmental factors known to influence the outcome of HCV infections was compared in 92 HCV spontaneous clearance subjects and 318 HCV persistent infection subjects. Univariate and multivariate analyses were performed to identify those factors associated with spontaneous HCV clearance. In univariate analysis, female gender, a history of icteric hepatitis, serologic evidence of concurrent HBV infection, and rs12979860 CC genotype were positively associated with spontaneous HCV clearance, while alcohol consumption was negatively associated with clearance. In multivariate analysis, female gender, a history of icteric hepatitis, concurrent HBV infection, and rs12979860 CC genotype remained independent variables associated with spontaneous HCV clearance. Spontaneous HCV clearance is more likely to occur in females, subjects with a history of icteric hepatitis, HBV coinfections, and those with the rs12979860 CC genotype.
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Improving abiotic reducing ability of hydrothermal biochar by low temperature oxidation under air.
Bioresour. Technol.
PUBLISHED: 07-14-2014
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Oxidized hydrothermal biochar was prepared by hydrothermal carbonization of Spartina alterniflora biomass (240°C for 4h) and subsequent oxidization (240°C for 10min) under air. Oxidized hydrochar achieved a Fe(III) reducing capacity of 2.15mmol/g at pH 2.0 with 120h, which is 1.2 times higher than un-oxidized hydrochar. Low temperature oxidization increases the contents of carboxyl and carbonyl groups on hydrochar surface. It is supposed that carboxyl groups provide bonding sites for soluble Fe species and carbonyl groups are responsible for Fe(3+) reduction. A Fenton-like process was established with Fe(2+) replaced by oxidized hydrochar and tested for methylene blue (MB) decoloration. Oxidized hydrochar achieved a MB decolorization (200mg/L, pH 7.0) rate of 99.21% within 3h and demonstrates prominent prevail over H2O2 absent control test. This study reveals low temperature oxidization is an effective way to improve and restore abiotic reducing ability of hydrochar.
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Adaptive Amphiphilic Dendrimer-Based Nanoassemblies as Robust and Versatile siRNA Delivery Systems.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 07-08-2014
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siRNA delivery remains a major challenge in RNAi-based therapy. Here, we report for the first time that an amphiphilic dendrimer is able to self-assemble into adaptive supramolecular assemblies upon interaction with siRNA, and effectively delivers siRNAs to various cell lines, including human primary and stem cells, thereby outperforming the currently available nonviral vectors. In addition, this amphiphilic dendrimer is able to harness the advantageous features of both polymer and lipid vectors and hence promotes effective siRNA delivery. Our study demonstrates for the first time that dendrimer-based adaptive supramolecular assemblies represent novel and versatile means for functional siRNA delivery, heralding a new age of dendrimer-based self-assembled drug delivery in biomedical applications.
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Apolipoprotein e mutation and double filtration plasmapheresis therapy on a new chinese patient with lipoprotein glomerulopathy.
Kidney Blood Press. Res.
PUBLISHED: 07-04-2014
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Lipoprotein glomerulopathy (LPG) is a rare hereditary disease. In this study, we investigated the apoE mutation and the role of double filtration plasmapheresis therapy (DFPP) on a new Chinese patient with LPG.
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Enhanced Glioma Targeting and Penetration by Dual-Targeting Liposome Co-modified with T7 and TAT.
J Pharm Sci
PUBLISHED: 07-02-2014
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The development of a drug delivery strategy that can not only cross the blood-brain barrier (BBB) rapidly, but also target the glioma and reach the core of glioma is essential and important for glioma treatment. To achieve this goal, we established a dual-targeting liposomal system modified with TAT (AYGRKKRRQRRR) and T7 (HAIYPRH), in which the specific ligand T7 could target BBB and brain glioma tumor and the nonspecific ligand TAT could enhance the effect of passing through BBB, and elevate the penetration into the tumor. The dual-targeting effects were evaluated by both in vitro and in vivo experiments. To identify the targeting effect, in vitro cellular uptake and BBB model were performed. Tumor spheroid penetration was performed to evaluate the penetration characteristics of the dual-targeting liposomes. In vivo pharmacokinetic studies were utilized to evaluate the influence of T7 and TAT peptides on the behavior of nanoparticle drug delivery system, and tissue distribution was further utilized to evaluate the glioma-targeting efficiency of the dual-targeting liposomes. 103:3891-3901, 2014.
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Lithium stimulates human bone marrow derived mesenchymal stem cell proliferation through GSK-3?-dependent ?-catenin/Wnt pathway activation.
FEBS J.
PUBLISHED: 07-02-2014
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Mesenchymal stem cells (MSCs) are multipotent cells that have been widely used in cell based transplantation therapy. The use of MSCs requires in vitro expansion in order to fulfill their regenerative capacity. Therefore the proliferative ability of MSCs is one of the key factors which determine MSC therapeutic efficacy. In the present study, we showed for the first time that lithium, a well-known antidepressant, reversibly promoted the proliferation of human bone marrow derived MSCs in vitro. MSCs treated with 5 mm lithium proliferated more rapidly than untreated cells without undergoing apoptosis. Lithium increased the proportion of cells in S phase as well as cyclin D1 expression. Mechanistic studies revealed that these effects were dependent upon the activation of the glycogen synthase kinase 3? (GSK-3?) mediated canonical Wnt pathway. Lithium induced Ser9 phosphorylation, which results in the inhibition of GSK-3? activity, ?-catenin accumulation and Wnt pathway activation. Utilizing a specific GSK-3? inhibitor SB216763 or siRNA-mediated inhibition of GSK-3? produced effects similar to those induced by lithium. In contrast, either quercetin, an inhibitor of the ?-catenin/TCF pathway, or siRNA-mediated knockdown of ?-catenin abolished the proliferative effect of lithium, suggesting that lithium stimulates MSC proliferation via the GSK-3?-dependent ?-catenin/Wnt pathway. Collectively, these studies elucidate a novel role of lithium, which may not only provide a simple and effective way to strengthen MSC transplantation therapy efficacy but also shed light on lithium's clinical application for the treatment of certain disorders resulting from ?-catenin/Wnt pathway suppression.
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A monoclonal antibody based enzyme-linked immunosorbent assay for detection of phenylethanolamine A in tissue of swine.
Food Chem
PUBLISHED: 07-01-2014
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Phenylethanolamine A (PEA) is a phenethanolamine member of the family of ?-adrenergic agonists compounds illegally used as feed additives for growth promotion. In this study, PEA was covalently linked to carrier protein cationized bovine serum albumin (cBSA) and egg albumin (OVA). A monoclonal antibody specific for PEA was produced and characteristics of monoclonal antibody (McAb) were studied. Based on the McAb, an enzyme-linked immunosorbent assay (ELISA) for detection of PEA was developed, which showed an IC50 value of 6.25 ng mL(-1) and a detection limit of 0.19 ng mL(-1). The average recovery of PEA from spiked samples was 103.4%, which demonstrated that the matrices of meat where PEA may be found do not interfere with the assay.
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Transcriptional profiling and dynamical regulation analysis identify potential kernel target genes of SCYL1-BP1 in HEK293T cells.
Mol. Cells
PUBLISHED: 06-30-2014
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SCYL1-BP1 is thought to function in the p53 pathway through Mdm2 and hPirh2, and mutations in SCYL1-BP1 are associated with premature aging syndromes such as Geroderma Osteodysplasticum; however, these mechanisms are unclear. Here, we report significant alterations in miRNA expression levels when SCYL1-BP1 expression was inhibited by RNA interference in HEK293T cells. We functionally characterized the effects of potential kernel miRNA-target genes by miRNA-target network and protein-protein interaction network analysis. Importantly, we showed the diminished SCYL1-BP1 dramatically reduced the expression levels of EEA1, BMPR2 and BRCA2 in HEK293T cells. Thus, we infer that SCYL1-BP1 plays a critical function in HEK293T cell development and directly regulates miRNA-target genes, including, but not limited to, EEA1, BMPR2, and BRCA2, suggesting a new strategy for investigating the molecular mechanism of SCYL1-BP1.
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Phenotype and expression profile analysis of Staphylococcus aureus biofilms and planktonic cells in response to licochalcone A.
Appl. Microbiol. Biotechnol.
PUBLISHED: 06-23-2014
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Staphylococcus aureus is one of the most important pathogens in humans and animals. The formation of biofilm by S. aureus is considered an important mechanism of antimicrobial resistance. Therefore, finding effective drugs against the biofilm produced by S. aureus has been a high priority. Licochalcone A (LAA), a natural plant product, was reported to have antibacterial activities and showed good activity against all 21 tested strains of S. aureus biofilm and planktonic cells. To detect the possible molecular mechanism of LAA against S. aureus biofilm or planktonic cells, Affymetrix GeneChips were used to determine the global comparative transcription of S. aureus biofilm and planktonic cells triggered by treatment with sub-bactericidal and sub-inhibitory concentrations of LAA, respectively. LAA significantly altered (greater than a 2- or less than -2-fold change) the expression of 693 genes in planktonic cells and 817 genes in biofilm. The levels of genes encoding autolysis-associated proteins, cell wall proteins, pathogenic factors, protein synthesis genes, and enzymes involved in capsule synthesis were significantly altered in LAA-treated S. aureus. Furthermore, some differences observed in the microarray analysis were verified by real-time RT-PCR. To our knowledge, this is the first observation of phenotype and expression profiles of S. aureus biofilm and planktonic cells in response to LAA treatment.
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Antimicrobial activity of the imipenem/rifampicin combination against clinical isolates of Acinetobacter baumannii grown in planktonic and biofilm cultures.
World J. Microbiol. Biotechnol.
PUBLISHED: 06-18-2014
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To investigate the antimicrobial activity of imipenem and rifampicin alone and in combination against clinical isolates of Acinetobacter baumannii grown in planktonic and biofilm cultures. Minimum inhibitory concentrations were determined for each isolate grown in suspension and in biofilm using a microbroth dilution method. Chequerboard assays and the agar disk diffusion assay were used to determine synergistic, indifferent or antagonistic interactions between imipenem and rifampicin. We used the tissue culture plate method for A. baumannii biofilm formation to measure the percentage of biofilm inhibition and the amount of extracellular DNA after the treatment. To understand the synergistic mechanisms, we conducted hydroxyl radical formation assays. The results were verified by confocal laser scanning microscopy. Imipenem and rifampicin showed effective antimicrobial activity against suspensions and biofilm cultures of A. baumannii, respectively. Synergistic antimicrobial effects between imipenem and rifampicin were observed in 13 and 17 of the 20 clinical isolates when in suspension and in biofilms, respectively. Imipenem and rifampicin alone and in combination generated hydroxyl radicals, which are highly reactive oxygen forms and the major components of bactericidal agents. Furthermore, treatment with imipenem and rifampicin individually or in combination has obvious antibiofilm effects. The synergistic activity of imipenem and rifampicin against clinical isolates of A. baumannii (in suspension and in biofilms) was observed in vitro. Therefore, we conclude that imipenem combined with rifampicin has the potential to be used as a combinatorial therapy for the treatment of infectious diseases caused by A. baumannii.
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Relationship between occupational stress and burnout among Chinese teachers: a cross-sectional survey in Liaoning, China.
Int Arch Occup Environ Health
PUBLISHED: 06-17-2014
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Teaching has been reported to be one of the most stressful occupations in the world. Few studies have been conducted to explore the effects of occupational stress on burnout among teachers in developing countries. This study aimed to explore the relationship between occupational stress and burnout among teachers in primary and secondary schools in the Liaoning Province of China.
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Analysis of the microbial community in moderately acidic drainage from the Yanahara pyrite mine in Japan.
Biosci. Biotechnol. Biochem.
PUBLISHED: 06-17-2014
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Acid rock drainage (ARD) originating from the Yasumi-ishi tunnel near the main tunnel of the Yanahara mine in Japan was characterized to be moderately acidic (pH 4.1) and contained iron at a low concentration (51?mg/L). The composition of the microbial community was determined by sequence analysis of 16S rRNA genes using PCR and denaturing gradient gel electrophoresis. The analysis of the obtained sequences showed their similarity to clones recently detected in other moderately acidic mine drainages. Uncultured bacteria related to Ferrovum- and Gallionella-like clones were dominant in the microbial community. Analyses using specific primers for acidophilic iron- or sulfur-oxidizing bacteria, Acidithiobacillus ferrooxidans, Leptospirillum spp., Acidithiobacillus caldus, Acidithiobacillus thiooxidans, and Sulfobacillus spp. revealed the absence of these bacteria in the microbial community in ARD from the Yasumi-ishi tunnel. Clones affiliated with a member of the order Thermoplasmatales were detected as the dominant archaea in the ARD microbial population.
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Catalytic asymmetric construction of 3,3'-spirooxindoles fused with seven-membered rings by enantioselective tandem reactions.
Chemistry
PUBLISHED: 06-07-2014
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The first catalytic asymmetric construction of a spirooxindole scaffold incorporated with a seven-membered benzodiazepine moiety has been established by a three-component (isatin, 1,2-phenylenediamine, cyclohexane-1,3-dione) tandem reaction catalyzed by a chiral phosphoric acid. Structurally complex spirobenzodiazepine oxindoles with one quaternary stereogenic center are obtained in high yield with excellent enantioselectivity (up to 99?% yield, enantiomeric ratio>99.5:0.5). This approach takes advantage of organocatalytic asymmetric tandem reactions to efficiently construct the structurally rigid spirobenzodiazepine oxindole architecture with high enantiopurity in a single transformation, which involves a cascade enamine-imine formation/intramolecular Mannich reaction sequence.
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Endoplasmic reticulum stress is involved in the connection between inflammation and autophagy in type 2 diabetes.
Gen. Comp. Endocrinol.
PUBLISHED: 05-31-2014
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Type 2 diabetes is a chronic inflammatory disease. A number of studies have clearly demonstrated that cytokines such as interleukin 1? (IL1?) contribute to pancreatic inflammation, leading to impaired glucose homeostasis and diabetic disease. There are findings which suggest that islet ?-cells can secrete cytokines and cause inflammatory responses. In this process, thioredoxin-interacting protein (TXNIP) is induced by endoplasmic reticulum (ER) stress, which further demonstrates a potential role for ER stress in innate immunity via activation of the NOD-like receptor (NLRP) 3/caspase1 inflammasome and in diabetes pathogenesis via the release of cytokines. Recent developments have also revealed a crucial role for the autophagy pathway during ER stress and inflammation. Autophagy is an intracellular catabolic system that not only plays a crucial role in maintaining the normal islet architecture and intracellular insulin content but also represents a form of programmed cell death. In this review, we focus on the roles of autophagy, inflammation, and ER stress in type 2 diabetes but, above all, on the connections among these factors.
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An Adenosine A1 Agonist 2-Chloro-N6 Cyclopentyladenosine Inhibits the Angiotensin II-Induced Cardiomyocyte Hypertrophy through the Calcineurin Pathway.
Cardiology
PUBLISHED: 05-30-2014
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The aim of this investigation was to study the underlying mechanism of an adenosine A1 receptor agonist 2-chloro-N6 cyclopentyladenosine (CCPA) inhibiting cardiomyocyte hypertrophy induced by angiotensin II (AngII).
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Adsorption of molybdate on molybdate-imprinted chitosan/triethanolamine gel beads.
Carbohydr Polym
PUBLISHED: 05-28-2014
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Mo (VI)-imprinted chitosan (CTS)/triethanolamine (TEA) gel beads (Mo (VI)-ICTGBs) (ICTGBs=imprinted chitosan triethanolamine gel beads) were prepared by using ion-imprinted technology, in which TEA and molybdate solution were used in coagulation bath. The spectrum of FT-IR implies that bonding are formed between TEA and the primary hydroxyl of CTS, and ion gel reaction happen between CTS and molybdate; XRD patterns also prove the change among CTS, TEA and molybdate. SEM images and N2 adsorption show that the surface area increases obviously after eluting Mo (VI) ions. The adsorption isotherm of Mo (VI)-ICTGBs imply that the adsorption process is according with Freundlich model. Adsorption kinetics suggests that the pseudo-second order adsorption mechanism is predominant for this adsorbent system of Mo (VI)-ICTGBs. The Mo (VI)-ICTGBs show high adsorption capacity and good selectivity for Mo (VI) anions in the coexistence system at pH=6.0. The Mo (VI)-ICTGBs have a good application prospect, because it is with a simple and rapid technique and good durance.
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The association between blood lipid and phlegm turbidity syndrome of angina pectoris: a systematic review and meta-analysis.
Complement Ther Med
PUBLISHED: 05-27-2014
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A series of case-control studies have been conducted to investigate the association between blood lipid and phlegm turbidity syndrome of angina pectoris, but produced inconsistent results.
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Bursin-like peptide (BLP) enhances H9N2 influenza vaccine induced humoral and cell mediated immune responses.
Cell. Immunol.
PUBLISHED: 05-26-2014
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Vaccination with H9N2 avian influenza whole-inactivated virus (WIV) has been shown to be ineffective at eliciting sufficient humoral and cellular immunity against H9N2 avian influenza virus. This study assessed the effects of a synthetic Bursin-like epitope peptide (BLP) as adjuvant for H9N2 WIV in mice. Titers HI and avian influenza virus neutralizing antibodies, subtypes of HA antibodies, T helper (Th) cytokine levels, cytotoxic T-lymphocyte activities and changes in spleen T-cell subsets and natural killer cells were determined. We found that BLP induced a balance between IgG1 and IgG2a secretion levels. WIV antigen alone induced mainly Th1 cytokines secretion, whereas BLP showed increased secretion of Th1 and Th2 cytokines, including interleukin (IL)-2, interferon-? (IFN-?) and IL-4, but not IL-10, and may be resembles a Th0 like response. BLP significantly promoted growth and expansion of natural killer cells and of CD4(+) and CD8(+) T-cell subsets in the spleen. Meanwhile, BLP induced a better cytotoxic T-lymphocyte response to H9N2 virus. Furthermore, virus challenge experiments confirmed that BLP contributed to inhibition replication of the virus from mouse lungs. Taken together, these findings suggest that BLP may be an effective adjuvant for H9N2 avian influenza vaccine.
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MEP Pathway-mediated isopentenol production in metabolically engineered Escherichia coli.
Microb. Cell Fact.
PUBLISHED: 05-19-2014
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BackgroundIsopentenols, such as prenol and isoprenol, are promising advanced biofuels because of their higher energy densities and better combustion efficiencies compared with ethanol. Microbial production of isopentenols has been developed recently via metabolically engineered E. coli. However, current yields remain low and the underlying pathways require systematic optimization.ResultsIn this study, we targeted the E. coli native 2-methyl-(D)-erythritol-4-phosphate (MEP) pathway and its upstream glycolysis pathway for the optimization of isopentenol production. Two codon optimized genes, nudF and yhfR from Bacillus subtilis, were synthesized and expressed in E. coli W3110 to confer the isopentenol production of the strain. Two key enzymes (IspG and Dxs) were then overexpressed to optimize the E. coli native MEP pathway, which led to a significant increase (3.3-fold) in isopentenol production. Subsequently, the glycolysis pathway was tuned to enhance the precursor and NADPH supplies for the MEP pathway by activating the pentose phosphate pathway (PPP) and Entner-Doudoroff pathway (ED), which resulted in additional 1.9 folds of increase in isopentenol production. A 5 L-scale batch cultivation experiment was finally implemented, showing a total of 61.9 mg L¿1 isopentenol production from 20 g L¿1 of glucose.ConclusionThe isopentenol production was successfully increased through multi-step optimization of the MEP and its upstream glycolysis pathways. It demonstrated that the total fluxes and their balance of the precursors of the MEP pathway are of critical importance in isopentenol production. In the future, an elucidation of the contribution of PPP and ED to MEP is needed for further optimization of isopentenol production.
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