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Find video protocols related to scientific articles indexed in Pubmed.
Comparison of waveguide properties and Raman spectroscopic visualization of C and O ion implantation on LaAlO3 crystals.
Appl Opt
PUBLISHED: 11-18-2014
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LaAlO3 crystals were implanted by C ions and O ions at an energy of 6.0 MeV with a fluence of 1.5×1015??ions/cm2. The profiles of the guided modes were measured through prism coupling and end-face coupling methods with a 633 nm laser source. A nonleaky waveguide structure in the TM mode was fabricated by O ion implantation after a proper annealing treatment. Characteristics of the implanted C and O ions were compared. Some changes of the full width at half of the maximum and intensity of the Raman spectra were observed between the waveguide and substrate regions in LaAlO3 crystals. Thus, the Raman spectra can be used to visualize any damage or defects in the LaAlO3 crystals during the implantation process.
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Dimer Involvement and Origin of Crossover in Nickel-Catalyzed Aldehyde-Alkyne Reductive Couplings.
J. Am. Chem. Soc.
PUBLISHED: 11-18-2014
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The mechanism of nickel(0)-catalyzed reductive cyclization of aldehydes and alkynes has been studied. Extensive double-labelling crossover studies have been conducted. While previous studies illustrated that phosphine- and N-heterocyclic carbene-derived catalysts exhibited differing behavior, the origin of these effects has now been evaluated in detail. Many variables including ligand class, sterics of the ligand and alkyne, temperature, and the ring size being formed in intramolecular versions all influence the extent of crossover observed. A computational evaluation of these effects suggests that dimerization of a key metallacyclic intermediate provides the origin of crossover. Protocols that proceed with crossover are typically less efficient than those without crossover given the thermodynamic stability and low reactivity of the dimeric metallacycles involved in crossover pathways.
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Allopurinol treatment improves renal function in patients with type 2 diabetes and asymptomatic hyperuricemia: a three years of randomized parallel-controlled study.
Clin. Endocrinol. (Oxf)
PUBLISHED: 11-18-2014
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To investigate the effects of long-term effective control of serum uric acid on renal function in patients with type 2 diabetes and asymptomatic hyperuricemia.
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Reduction-responsive core-shell-corona micelles based on triblock copolymer: novel synthetic strategy, characterization, and application as tumor microenvironment-responsive drug delivery system.
ACS Appl Mater Interfaces
PUBLISHED: 11-15-2014
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A facile and effective approach was established for fabricating core-shell-corona micelles by self-assembly of poly(ethylene glycol)-b-poly(acrylic acid-co-tert-butyl acrylate)-poly(?-caprolactone) (PEG43-b-P(AA30-co-tBA18)-b-PCL53) triblock copolymer, synthesized via combination of ROP, ATRP, click chemistry and hydrolyzation. The pre-nanovehicles with three different hydrolysis degrees from PEG43-b-PtBA48-b-PCL53 were developed to evaluate the drug loading capacity (DLC) and drug encapsulation efficiency (DEE). After crosslinking with disulfide bond to regulate the drug release kinetics, the spherical core-shell-corona micelles with average diameter of 52±4 nm were obtained in aqueous solution. The reduction-responsive crosslinked micelles showed a slow sustained release in normal physiological condition and a rapid release upon exposing to simulated tumor intracellular conditions. In addition, the cytotoxic analysis and HepG2 cell growth inhibition assays demonstrated their remarkable biocompatibility and similar excellent anticancer activity as the free DOX, which has also been revealed by the CLSM analysis. So the reduction-sensitive core-shell-corona micelles are expected to be promising tumor microenvironment-responsive nanovehicles for hydrophobic drugs by GSH triggering.
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New Insights into Thermal Decomposition of PAHs OxyRadicals.
J Phys Chem A
PUBLISHED: 11-12-2014
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Thermal decompositions of PAHs oxyradicals on various surface sites including five-membered ring, free-edge, zig-zag, and armchair have been systematically investigated by using ab initio density functional theory B3LYP/6-311+G(d,p) basis set. The calculation based on Hückel theory indicates that PAHs (3H-cydopenta[a]anthracene oxyradical) with oxyradicals on five-membered ring site have high chemical reactivity. The rate coefficients of PAHs oxyradicals decomposition were evaluated by using RRKM theory and solving the master equations in the temperature range of 1500-2500 K and the pressure range of 0.1-10 atm. The kinetic calculations revealed that the rate coefficients of PAHs oxyradicals decomposition are temperature, pressure and surface site dependent, and the oxyradical on five-membered ring is easier to be decomposed than that on six-membered ring. Four-membered rings were found in decomposition of five-membered ring, and a new reaction channel of PAHs evolution involving four-membered rings is recommended.
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Reactivity and Chemoselectivity of Allenes in Rh(I)-Catalyzed Intermolecular (5+2) Cycloadditions with Vinylcyclopropanes: Allene-Mediated Rhodacycle Formation Can Poison Rh(I)-Catalyzed Cycloadditions.
J. Am. Chem. Soc.
PUBLISHED: 11-08-2014
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Allenes are important 2? building blocks in organic synthesis and engage as 2-carbon components in many metal-catalyzed reactions. Wender and co-workers discovered that methyl substituents on the terminal allene double bond counter-intuitively change the reactivities of allenes in [Rh(CO)2Cl]2-catalyzed intermolecular (5+2) cycloadditions with vinylcyclopropanes (VCPs). More sterically encumbered allenes afford higher cycloadduct yields, and such effects are also observed in other Rh(I)-catalyzed intermolecular cycloadditions. Through density functional theory calculations (B3LYP and M06) and experiment, we explored this enigmatic reactivity and selectivity of allenes in [Rh(CO)2Cl]2-catalyzed intermolecular (5+2) cycloadditions with VCPs. The apparent low reactivity of terminally unsubstituted allenes is associated with a competing allene dimerization that irreversibly sequesters rhodium. With terminally substituted allenes, steric repulsion between the terminal substituents significantly increase the barrier of allene dimerization while the barrier of the (5+2) cycloaddition is not affected, and thus the cycloaddition prevails. Computation has also revealed the origin of chemoselectivity in (5+2) cycloadditions with allene-ynes. Although simple allene and acetylene have similar reaction barriers, intermolecular (5+2) cycloadditions of allene-ynes occur exclusively at the terminal allene double bond. The terminal double bond is more reactive due to the enhanced d-?(?) backdonation. At the same time, insertion of the internal double bond of an allene-yne has a higher barrier as it would break ? conjugation. Substituted alkynes are more difficult to insert compared with acetylene, because of the steric repulsion from the additional substituents. This leads to the greater reactivity of the allene double bond relative to the alkynyl group in allene-ynes.
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Hydrophobic-polymer-grafted graphene oxide nanosheets as an easily separable adsorbent for the removal of tetrabromobisphenol a.
Langmuir
PUBLISHED: 11-06-2014
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Hydrophobic polymer brushes have been grafted from graphene oxide nanosheets (GO) via the facile surface-initiated redox radical polymerization of tert-butyl acrylate (tBA) from the GO with cerium ammonium nitrate (CAN) as an oxidant. After the hydrophobic surface modification, the poly(tert-butyl acrylate) (PtBA)-grafted graphene oxide nanosheets (GO-PtBA) could still be dispersed in water because of the remaining oxygen-containing groups but deposited within 40 min. The feature makes it an easily separable adsorbent for environmental pollutants. For example, tetrabromobisphenol A (TBBPA) could be removed from aqueous solution via hydrogen bonds (between hydroxyl groups of TBBPA and hydroxyl and carboxyl groups of GO) and ?-? interactions (between the benzene ring of TBBPA and GO), with an adsorption capacity of 22.2 mg g(-1) at pH 7.0. The TBBPA-adsorbed GO-PtBA could be deposited completely within 30 min, and the adsorbed TBBPA could be easily desorbed with ethanol, demonstrating its good recyclability.
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[Expression of FOXC1 and its relationship with E-cadherin in nasopharyngeal carcinoma tissues].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 10-18-2014
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To investigate the significance and relationship between the expression of FOXC1 and clinicopathological features, and to explore its correlation with E-cadherin.
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[Metabolic pathway and metabolites of total diterpene acid isolated from Pseudolarix kaempferi].
Yao Xue Xue Bao
PUBLISHED: 10-18-2014
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The preliminary metabolic profile of total diterpene acid (TDA) isolated from Pseudolarix kaempferi was investigated by using in vivo and in vitro tests. Pseudolaric acid C2 (PC2) was identified as the predominant metabolite in plasma, urine, bile and feces after both oral and intravenous administrations to rats using HPLC-UV and HPLC-ESI/MS(n), and demethoxydeacetoxypseudolaric acid B (DDPB), a metabolite proposed to be the glucoside of PC2 (PC2G), as well as pseudolaric acid C (PC), pseudolaric acid A (PA), pseudolaric acid A O-beta-D glucopyranoside (PAG), pseudolaric acid B O-beta-D glucopyranoside (PBG) and deacetylpseudolaric acid A (DPA) originated from TDA could also be detected. It was demonstrated by tests that the metabolism of TDA is independent of intestinal microflora, and neither of pepsin and trypsin is in charge of metabolism of TDA, TDA is also stable in both pH environments of gastric tract and intestinal tract. The metabolites of TDA in whole blood in vitro incubation were found to be PC2, DDPB and PC2G, which demonstrated that the metabolic reaction of TDA in vivo is mainly occurred in blood and contributed to be the hydrolysis of plasma esterase to ester bond, as well as the glucosylation reaction. These results clarified the metabolic pathway of TDA for the first time, which is of great significance to the in vivo active form and acting mechanism research of P. kaempferi.
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miR-185 suppresses tumor proliferation by directly targeting E2F6 and DNMT1 and indirectly up-regulating BRCA1 in triple negative breast cancer.
Mol. Cancer Ther.
PUBLISHED: 10-17-2014
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Breast cancer is a major public health problem all over the world, and the current treatment strategies are not potent enough for some patients, especially those with triple-negative breast cancer (TNBC). Recent studies have demonstrated that microRNAs (miRNAs) play vital roles in the development of TNBC. In this study, we found that miR-185 was strongly downregulated in triple negative breast cancer tissues and cell lines and that its expression levels were associated with lymph node metastasis, clinical stage, overall survival and relapse-free survival in TNBC. We also found that ectopic expression of miR-185 inhibited TNBC cell proliferation in vitro and in vivo. We further identified that miR-185 directly targeted DNMT1 and E2F6, which resulted in a marked increase in the expression of BRCA1 at the mRNA and protein levels in TNBC. Our data suggest that miR-185 functions as a tumour suppressor in TNBC development. It is a promising prognostic biomarker and potential therapeutic target for TNBC.
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Complexation mechanism of cucurbit[6]uril with hexamethylene diammonium cations in saline solution.
Phys Chem Chem Phys
PUBLISHED: 10-15-2014
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Binding of cucurbit[6]uril (CB[6]) with the hexamethylene diammonium cation (HD(2+)) in the presence of sodium ions is elucidated at the atomic level. The most probable complex of CB[6] in saline solution is found to be CB[6]:Na(+). A two-stage binding process of CB[6]:Na(+) with HD(2+) is proposed.
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Liposome encapsulated Disulfiram inhibits NF?B pathway and targets breast cancer stem cells in vitro and in vivo.
Oncotarget
PUBLISHED: 10-04-2014
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Breast cancer stem cells (BCSCs) are pan-resistant to different anticancer agents and responsible for cancer relapse. Disulfiram (DS), an antialcoholism drug, targets CSCs and reverses pan-chemoresistance. The anticancer application of DS is limited by its very short half-life in the bloodstream. This prompted us to develop a liposome-encapsulated DS (Lipo-DS) and examine its anticancer effect and mechanisms in vitro and in vivo. The relationship between hypoxia and CSCs was examined by in vitro comparison of BC cells cultured in spheroid and hypoxic conditions. To determine the importance of NF?B activation in bridging hypoxia and CSC-related pan-resistance, the CSC characters and drug sensitivity in BC cell lines were observed in NF?B p65 transfected cell lines. The effect of Lipo-DS on the NF?B pathway, CSCs and chemosensitivity was investigated in vitro and in vivo. The spheroid cultured BC cells manifested CSC characteristics and pan-resistance to anticancer drugs. This was related to the hypoxic condition in the spheres. Hypoxia induced activation of NF?B and chemoresistance. Transfection of BC cells with NF?B p65 also induced CSC characters and pan-resistance. Lipo-DS blocked NF?B activation and specifically targeted CSCs in vitro. Lipo-DS also targeted the CSC population in vivo and showed very strong anticancer efficacy. Mice tolerated the treatment very well and no significant in vivo nonspecific toxicity was observed. Hypoxia induced NF?B activation is responsible for stemness and chemoresistance in BCSCs. Lipo-DS targets NF?B pathway and CSCs. Further study may translate DS into cancer therapeutics.
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[Ultrasmall superparamagnetic iron oxide-enhanced magnetic resonance angiography combined with inflammatory factors for detecting atherosclerotic plaques in rabbits].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 09-30-2014
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To investigate the feasibility of Ultrasmall superparamagnetic iron oxide-enhanced magnetic resonance angiography (USPIO-MRA) combined with interleukin-6 (IL-6) and IL-10 detection for detecting atherosclerotic plaques in rabbits.
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Mitochondrial DNA common deletion increases susceptibility to noise-induced hearing loss in a mimetic aging rat model.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-23-2014
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Noise-induced hearing loss (NIHL) is an important occupational health hazard. However, susceptibility to NIHL remains poorly understood. The present study was designed to investigate whether mitochondrial DNA common deletion (CD) increases the susceptibility of individuals to NIHL. A mimetic aging rat model harboring increased CD in the inner ear was established by chronic d-galactose administration, and the synergic effect of CD and noise on hearing sensitivity was assessed. We determined that although developed the same magnitude of temporary threshold shifts and hair cell loss, the d-galactose treated rats with increased CD in the inner ear exhibited a longer hearing recovery process and experienced higher permanent hearing threshold shifts at high frequencies than the saline-treated control rats. Greater supporting cell damage and stria vascularis ultrastructural changes were observed in d-galactose treated rats three weeks after recovery. The results suggested that the elevated CD in the inner ear could increase an individual's susceptibility to NIHL, which likely through a reduction in the self-repairing capability within the cochlea after acoustic injury.
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Proteinase 3-dependent caspase-3 cleavage modulates neutrophil death and inflammation.
J. Clin. Invest.
PUBLISHED: 09-02-2014
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Caspase-3-mediated spontaneous death in neutrophils is a prototype of programmed cell death and is critical for modulating physiopathological inflammatory responses; however, the underlying regulatory pathways remain ill defined. Here we determined that in aging neutrophils, the cleavage and activation of caspase-3 is independent of the canonical caspase-8- or caspase-9-mediated pathway. Instead, caspase-3 activation was mediated by serine protease proteinase 3 (PR3), which is present in the cytosol of aging neutrophils. Specifically, PR3 cleaved procaspase-3 at a site upstream of the canonical caspase-9 cleavage site. In mature neutrophils, PR3 was sequestered in granules and released during aging via lysosomal membrane permeabilization (LMP), leading to procaspase-3 cleavage and apoptosis. Pharmacological inhibition or knockdown of PR3 delayed neutrophil death in vitro and consistently delayed neutrophil death and augmented neutrophil accumulation at sites of inflammation in a murine model of peritonitis. Adoptive transfer of both WT and PR3-deficient neutrophils revealed that the delayed death of neutrophils lacking PR3 is due to an altered intrinsic apoptosis/survival pathway, rather than the inflammatory microenvironment. The presence of the suicide protease inhibitor SERPINB1 counterbalanced the protease activity of PR3 in aging neutrophils, and deletion of Serpinb1 accelerated neutrophil death. Taken together, our results reveal that PR3-mediated caspase-3 activation controls neutrophil spontaneous death.
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Icaritin ameliorates carbon tetrachloride-induced acute liver injury mainly because of the antioxidative function through estrogen-like effects.
In Vitro Cell. Dev. Biol. Anim.
PUBLISHED: 08-23-2014
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To investigate the effects of icaritin, an active ingredient extracted from Epimedium Sagittatum (Sieb. et Zucc.), on CCl4-induced liver injury and its possible mechanisms. Hepatocytes isolated from Sprague-Dawley male rats were treated with 3 mmol/L CCl4 for 24 h to induce acute liver cell injury, then icaritin (0.1, 1, 10, 100 ?mol/L, respectively) was administrated to the cells, and estrogen receptor antagonist ICI182,780 (1 ?mol/L) was co-treated with 10 ?mol/L icaritin. Biochemical parameters (alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA), and superoxide dismutase (SOD)) and cell apoptosis were detected to evaluate the injury degree. Protein expressions of Bax, Bcl-2, liver fatty acid-binding protein (L-FABP), and peroxisome proliferator-activated receptor-? (PPAR-?) as well as reactive oxygen species (ROS) generation were determined by western blot. Icaritin alleviated CCl4-induced liver cell injury in a concentration-dependent manner and 10 ?mol/L was the optimal concentration. Icaritin (10 ?mol/L) significantly reduced activities of ALT, AST in cell culture medium and MDA level of the impaired liver cells, but increased the intercellular SOD activity. The apoptotic rate of the impaired liver cells was also decreased by icaritin (10 ?mol/L) treatment. Icaritin might exert antioxidative and anti-apoptotic functions via estrogen-like effect, as the ratio of Bcl-2/Bax was significantly increased, while protein expressions of L-FABP and PPAR-? were markedly increased, and this function was blocked by the estrogen receptor antagonist ICI182,780 efficiently. Icaritin may be a promising drug candidate for acute liver injury benefiting from the antioxidative and anti-apoptotic functions via estrogen-like effect.
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Interaction Studies Between Indomethacin Nanocrystals and PEO/PPO Copolymer Stabilizers.
Pharm. Res.
PUBLISHED: 08-22-2014
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The lack of effective screening methods and systemic understanding of interaction mechanisms complicates the stabilizer selection process for nanocrystallization. This study focuses on the efficiency of stabilizers with various molecular compositions and structures to stabilize drug nanocrystals.
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Sympathetic denervation-induced MSC mobilization in distraction osteogenesis associates with inhibition of MSC migration and osteogenesis by norepinephrine/adrb3.
PLoS ONE
PUBLISHED: 08-21-2014
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The sympathetic nervous system regulates bone formation and resorption under physiological conditions. However, it is still unclear how the sympathetic nerves affect stem cell migration and differentiation in bone regeneration. Distraction osteogenesis is an ideal model of bone regeneration due to its special nature as a self-engineering tissue. In this study, a rat model of mandibular distraction osteogenesis with transection of cervical sympathetic trunk was used to demonstrate that sympathetic denervation can deplete norepinephrine (NE) in distraction-induced bone callus, down-regulate ?3-adrenergic receptor (adrb3) in bone marrow mesenchymal stem cells (MSCs), and promote MSC migration from perivascular regions to bone-forming units. An in vitro Transwell assay was here used to demonstrate that NE can inhibit stroma-derived factor-1 (SDF-1)-induced MSC migration and expression of the migration-related gene matrix metalloproteinase-2 (MMP-2) and downregulate that of the anti-migration gene tissue inhibitor of metalloproteinase-3 (TIMP-3). Knockdown of adrb3 using siRNA abolishes inhibition of MSC migration. An in vitro osteogenic assay was used to show that NE can inhibit the formation of MSC bone nodules and expression of the osteogenic marker genes alkaline phosphatase (ALP), osteocalcin (OCN), and runt-related transcription factor-2 (RUNX2), but knockdown of adrb3 by siRNA can abolish such inhibition of the osteogenic differentiation of MSCs. It is here concluded that sympathetic denervation-induced MSC mobilization in rat mandibular distraction osteogenesis is associated with inhibition of MSC migration and osteogenic differentiation by NE/adrb3 in vitro. These findings may facilitate understanding of the relationship of MSC mobilization and sympathetic nervous system across a wide spectrum of tissue regeneration processes.
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Biocompatible graphene oxide nanoparticle-based drug delivery platform for tumor microenvironment-responsive triggered release of doxorubicin.
Langmuir
PUBLISHED: 08-20-2014
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A facile strategy was established to develop a drug delivery system (DDS) based on the graphene oxide nanoparticles (GON) with suitable size and shape to deliver drug effectively, by grafting the biocompatible PEGylated alginate (ALG-PEG) brushes onto the GON via the disulfide bridge bond. TEM analysis and drug-loading performance revealed that the 3-D nanoscaled, biocompatible, reduction-responsive nanocarriers (GON-Cy-ALG-PEG) were spherical in shape with diameters of 94.73 ± 9.56 nm. They possessed high doxorubicin (DOX)-loading capacity and excellent encapsulation efficiency, owing to their unique 3-D nanoscaled structure. They also had excellent stability in simulated physiological conditions and remarkable biocompatibility. Importantly, the in vitro release showed that the platform could not only prevent the leakage of the loaded DOX under physiological conditions but also detach the cytamine (Cy) modified PEGylated alginate (Cy-ALG-PEG) moieties, response to glutathione (GSH). Confocal microscopy and WST-1 assays provided clear evidence of the DOX-loaded GON-Cy-ALG-PEG endocytosis, whereas the drug-loaded nanocarriers exhibited high cytotoxicity to model cells. Furthermore, the cell apoptosis also was monitored via Flow cytometry. The results indicated that the DOX-loaded nanocarriers presented favorable efficiency of cell apoptosis. So these findings demonstrate that the accelerated release of the loaded DOX was realized in the presence of an elevated GSH that simulate the acidic endosomal compartments.
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Solvent Effects on Polymer Sorting of Carbon Nanotubes with Applications in Printed Electronics.
Small
PUBLISHED: 08-19-2014
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Regioregular poly(3-alkylthiophene) (P3AT) polymers have been previously reported for the selective, high-yield dispersion of semiconducting single-walled carbon nanotubes (SWCNTs) in toluene. Here, five alternative solvents are investigated, namely, tetrahydrofuran, decalin, tetralin, m-xylene, and o-xylene, for the dispersion of SWCNTs by poly(3-dodecylthiophene) P3DDT. The dispersion yield could be increased to over 40% using decalin or o-xylene as the solvents while maintaining high selectivity towards semiconducting SWCNTs. Molecular dynamics (MD) simulations in explicit solvents are used to explain the improved sorting yield. In addition, a general mechanism is proposed to explain the selective dispersion of semiconducting SWCNTs by conjugated polymers. The possibility to perform selective sorting of semiconducting SWCNTs using various solvents provides a greater diversity of semiconducting SWCNT ink properties, such as boiling point, viscosity, and surface tension as well as toxicity. The efficacy of these new semiconducting SWCNT inks is demonstrated by using the high boiling point and high viscosity solvent tetralin for inkjet-printed transistors, where solvent properties are more compatible with the inkjet printing head and improved droplet formation.
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[Effects of shading on endogenous hormones regulation in kernel development of summer maize in the field].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 08-19-2014
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Taking 3 maize hybrids, Zhenjie 2 (ZJ2), Denghai 605 (DH605) and Zhengdan 958 (ZD958) as test materials, the effects of shading on the physiological function of endogenous hormones during grain formation of summer maize were investigated in the field. The ambient sunshine treatment was used as the control (CK) and 3 shading treatments with a shading degree of 60% were designed in growth periods ranging from tasseling to maturity (S1), from jointing to tasseling stage (S2) and whole growing period (S3), respectively. Results showed that the total floret number, filament number and pollination floret number decreased after shading in comparison with CK, and aborted seeds increased accordingly. The kernels per ear showed an order of CK > S2 > S > S3, and those of S1, S2 and S3 were 18.9%, 43.7% and 80.8% lower than that of CK. The IAA, GA and ZR contents of normal grain in the shading treatments were lower than in CK, while the ABA content was opposite. The same hormone change with grain growth in all treatments presented a similar trend. Compared to normal grains, the maximum value of IAA content in aborted grains shifted from the 20th day to the 10th day after pollination, with less IAA accumulation and rapid reduction, and the contents of GA and ZR decreased significantly, while that of ABA was still high at the 20th day after pollination. Therefore, the effects of shading on hormone contents in grains might lead to grain abortion and yield reduction.
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Carbazole-based hole-transport materials for efficient solid-state dye-sensitized solar cells and perovskite solar cells.
Adv. Mater. Weinheim
PUBLISHED: 08-15-2014
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Two carbazole-based small molecule hole-transport materials (HTMs) are synthesized and investigated in solid-state dye-sensitized solar cells (ssDSCs) and perovskite solar cells (PSCs). The HTM X51-based devices exhibit high power conversion efficiencies (PCEs) of 6.0% and 9.8% in ssDSCs and PSCs, respectively. These results are superior or comparable to those of 5.5% and 10.2%, respectively, obtained for the analogous cells using the state-of-the-art HTM Spiro-OMeTAD.
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Pyrolysis characteristics and kinetic analysis of different dewatered sludge.
Bioresour. Technol.
PUBLISHED: 08-12-2014
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Pyrolysis behavior and kinetic properties of four different sludge, including raw sludge and three sludge respectively dewatered with FeCl3/CaO, FeCl3/CaO/coal and Fenton's reagent (Fe(2+)+H2O2)/CaO, were analyzed by using thermogravimetry coupled with Fourier transform infrared spectrometry (TG-FTIR). The results show that organics of raw sludge mainly decomposed at 378-676K, and the decomposition temperature of conditioned sludge was prolonged to 823K. Addition of coal and catalysis of CaO/ferric salt both promoted sludge pyrolysis, leading to more NH3, CH4 and CO productions. Compared with dry sludge, wet sludge pyrolysis was hard to finish completely, and the first peak of organics' decomposition appeared at higher temperature (about 573K). Additionally, the global reaction model was suited to determine kinetic parameters, which showed that dry sludge conditioned with more CaO addition had higher E values than those of dry raw sludge. Opposite results were obtained when sludge samples were wet.
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Xanthoceraside induces apoptosis in melanoma cells through the activation of caspases and the suppression of the IGF-1R/Raf/MEK/ERK signaling pathway.
J Med Food
PUBLISHED: 08-12-2014
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Xanthoceraside, a saponin extracted from the husks of Xanthoceras sorbifolia Bunge, suppresses inflammation and oxidative stress. However, the antitumor properties of xanthoceraside as well as its mechanism of action remain unclear. Therefore, we proposed to investigate its potential anticancer property. In this study, the viability of cells was measured by the MTT assay. Cell cycle and mitochondrial membrane potential were measured by flow cytometry, and the expressions of procaspase-9, procaspase-3, Cyto.c, Apaf-1, Bcl-2, Bcl-xL, Bad, p53, and IGF-1R/Raf/MEK/ERK were tested by Western blotting. Xanthoceraside significantly inhibited the proliferation of human melanoma A375.S2 cells in a concentration- and time-dependent manner but did not impair the viability of normal cells (peripheral blood mononuclear cells). Further analysis revealed that xanthoceraside induced apoptosis by activating caspase-3 and caspase-9 in a time-dependent manner through the mitochondrial pathway but did not activate caspase-8 in the cells. In addition, xanthoceraside inhibited the expression of the insulin-like growth factor-1 receptor (IGF-1R), which is an important prosurvival, antiapoptotic signaling growth factor receptor that is frequently overexpressed in cancer cells and used as a therapeutic target for multiple cancers. Interestingly, xanthoceraside also decreased the expression of Raf, p-MEK, and p-ERK, the downstream effectors of IGF-1R. Taken together, these findings indicate that xanthoceraside induces apoptosis through a mitochondria-mediated apoptotic pathway, which is induced by the downregulation of IGF-1R/Raf/MEK/ERK cascades in A375.S2 cells.
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A new model for predicting non-sentinel lymph node status in Chinese sentinel lymph node positive breast cancer patients.
PLoS ONE
PUBLISHED: 08-11-2014
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Our goal is to validate the Memorial Sloan-Kettering Cancer Center (MSKCC) nomogram and Stanford Online Calculator (SOC) for predicting non-sentinel lymph node (NSLN) metastasis in Chinese patients, and develop a new model for better prediction of NSLN metastasis.
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N6-substituted adenosine analogues, a novel class of JAK2 inhibitors, potently block STAT3 signaling in human cancer cells.
Cancer Lett.
PUBLISHED: 08-11-2014
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The JAK2/STAT3 signaling pathway plays a critical role in oncogenesis and malignancy, which makes it a promising anticancer target. We report four N(6)-substituted adenosine analogues (AAs) as potential JAK2/STAT3 inhibitors identified through a STAT3-based high-throughput drug screening system. These AAs exhibited selective anti-cancer activity on human cancer cells and xenograft tumors with constitutively activated STAT3. They rapidly and potently suppressed constitutive and IL-6/IFN-?-induced JAK2/STAT3 signal activation. In addition, we finally proved that the STAT3 signal blockage by three of these AAs was dependent on specific JAK2 inhibition. These AAs may represent new targeted therapeutic agents for JAK2/STAT3 hyper-activated human cancers.
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Synthesis and structure-activity relationships of PI3K/mTOR dual inhibitors from a series of 2-amino-4-methylpyrido[2,3-d]pyrimidine derivatives.
Bioorg. Med. Chem. Lett.
PUBLISHED: 08-07-2014
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Inhibition of the phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway by PI3K/mTOR dual inhibitors provides a promising new approach to the treatment of cancers. In this Letter, we identified structurally novel and potent PI3K/mTOR dual inhibitors from a series of 2-amino-4-methylpyrido[2,3-d]pyrimidine derivatives. Their synthesis and structure-activity relationships are reported.
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Meta-analysis of the association between two neprilysin gene polymorphisms and Alzheimer's disease.
J. Neurol. Sci.
PUBLISHED: 08-07-2014
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The aim of this study is to evaluate the association between two neprilysin variants (rs989692 and rs3736187) and Alzheimer's disease (AD).
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Lymphatic-targeted cationic liposomes: a robust vaccine adjuvant for promoting long-term immunological memory.
Vaccine
PUBLISHED: 08-07-2014
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Although retaining antigens at the injection site (the so-called "depot effect") is an important strategy for vaccine development, increasing evidence showed that lymphatic-targeted vaccine delivery with liposomes could be a promising approach for improving vaccine efficacy. However, it remains unclear whether antigen depot or lymphatic targeting would benefit long-term immunological memory, a major determinant of vaccine efficacy. In the present study, OVA antigen was encapsulated with DOTAP cationic liposomes (LP) or DOTAP-PEG-mannose liposomes (LP-Man) to generate depot or lymphatic-targeted liposome vaccines, respectively. The result of in vivo imaging showed that LP mostly accumulated near the injection site, whereas LP-Man not only effectively accumulated in draining lymph nodes (LNs) and the spleen, but also enhanced the uptake by resident antigen-presenting cells. Although LP vaccines with depot effect induced anti-OVA IgG more potently than LP-Man vaccines did on day 40 after priming, they failed to mount an effective B-cell memory response upon OVA re-challenge after three months. In contrast, lymphatic-targeted LP-Man vaccines elicited sustained antibody production and robust recall responses three months after priming, suggesting lymphatic targeting rather than antigen depot promoted the establishment of long-term memory responses. The enhanced long-term immunological memory by LP-Man was attributed to vigorous germinal center responses as well as increased Tfh cells and central memory CD4(+) T cells in the secondary lymphoid organs. Hence, lymphatic-targeted vaccine delivery with LP-Man could be an effective strategy to promote long-lasting immunological memory.
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A folate-integrated magnetic polymer micelle for MRI and dual targeted drug delivery.
Nanoscale
PUBLISHED: 08-06-2014
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This paper devotes a novel micellar structure for cancer theranostics by incorporating magnetic and therapeutic functionalities into a natural sourced targeting polymer vehicle. Heparin-folic acid micelles taking advantage of both excellent loading capability and cancer targeting ability have been employed to simultaneously incorporate superparamagnetic iron oxide nanoparticles (SPIONs) and doxorubicin through an ultrasonication-assisted microemulsion method. In this system, folic acids not only take the responsibility of micelle construction, but also facilitate cellular uptake due to their specific reorganization by MCF-7 cells over-expressing folate receptors. The obtained micelles exhibit good colloidal stability, a high magnetic content, considerable drug loading and sustained in vitro drug release. These clustered SPIONs exhibited high r2 relaxivity (243.65 mM(-1) s(-1)) and further served as efficient probes for MR imaging. Notably, the transport efficiency of these micelles could be significantly improved under an external magnetic field, owing to their quick magnetic response. As a result, the as-proposed micelle shows great potential in multimodal theranostics, including active targeting, MRI diagnosis and drug delivery.
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Visible and near-infrared optical properties of a proton-implanted KTP waveguide.
Appl Opt
PUBLISHED: 08-05-2014
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In this work, the optical properties of potassium titanyl phosphate (KTP) waveguides in the visible and near-infrared region are reported. The KTP waveguides were fabricated using 550 keV proton implantation at room temperature, and the refractive index profiles of the implanted region in the visible and near-infrared region were reconstructed. The profiles of the guided modes were measured through the end-face coupling method with both 632.8 and 1539 nm laser sources and then compared with the simulation results using the beam propagation method. Optical transmission and Raman spectra in the original substrate and waveguide active region were measured to study microstructural changes. The propagation loss of the TM0-mode at 632.8 nm was also measured.
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Mice lacking Axl and Mer tyrosine kinase receptors are susceptible to experimental autoimmune orchitis induction.
Immunol. Cell Biol.
PUBLISHED: 07-31-2014
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The mammalian testis is an immunoprivileged organ where male germ cell autoantigens are immunologically ignored. Both systemic immune tolerance to autoantigens and local immunosuppressive milieu contribute to the testicular immune privilege. Testicular immunosuppression has been intensively studied, but information on systemic immune tolerance to autoantigens is lacking. In the present study, we aimed to determine the role of Axl and Mer receptor tyrosine kinases in maintaining the systemic tolerance to male germ cell antigens using the experimental autoimmune orchitis (EAO) model. Axl and Mer double-knockout (Axl(-/-)Mer(-/-)) mice developed evident EAO after a single immunization with germ cell homogenates emulsified with complete Freund's adjuvant. EAO was characterized by the accumulation of macrophages and T lymphocytes in the testis. Damage to the seminiferous epithelium was also observed. EAO induction was associated with pro-inflammatory cytokine upregulation in the testes, impaired permeability of the blood-testis barrier and generation of autoantibodies against germ cell antigens in Axl(-/-)Mer(-/-) mice. Immunization also induced mild EAO in Axl or Mer single-gene-knockout mice. By contrast, a single immunization failed to induce EAO in wild-type mice. The results indicate that Axl and Mer receptors cooperatively regulate the systemic immune tolerance to male germ cell antigens.Immunology and Cell Biology advance online publication, 18 November 2014; doi:10.1038/icb.2014.97.
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A filter paper-based microdevice for low-cost, rapid, and automated DNA extraction and amplification from diverse sample types.
Lab Chip
PUBLISHED: 07-30-2014
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A plastic microfluidic device that integrates a filter disc as a DNA capture phase was successfully developed for low-cost, rapid and automated DNA extraction and PCR amplification from various raw samples. The microdevice was constructed by sandwiching a piece of Fusion 5 filter, as well as a PDMS (polydimethylsiloxane) membrane, between two PMMA (poly(methyl methacrylate)) layers. An automated DNA extraction from 1 ?L of human whole blood can be finished on the chip in 7 minutes by sequentially aspirating NaOH, HCl, and water through the filter. The filter disc containing extracted DNA was then taken out directly for PCR. On-chip DNA purification from 0.25-1 ?L of human whole blood yielded 8.1-21.8 ng of DNA, higher than those obtained using QIAamp® DNA Micro kits. To realize DNA extraction from raw samples, an additional sample loading chamber containing a filter net with an 80 ?m mesh size was designed in front of the extraction chamber to accommodate sample materials. Real-world samples, including whole blood, dried blood stains on Whatman® 903 paper, dried blood stains on FTA™ cards, buccal swabs, saliva, and cigarette butts, can all be processed in the system in 8 minutes. In addition, multiplex amplification of 15 STR (short tandem repeat) loci and Sanger-based DNA sequencing of the 520 bp GJB2 gene were accomplished from the filters that contained extracted DNA from blood. To further prove the feasibility of integrating this extraction method with downstream analyses, "in situ" PCR amplifications were successfully performed in the DNA extraction chamber following DNA purification from blood and blood stains without DNA elution. Using a modified protocol to bond the PDMS and PMMA, our plastic PDMS devices withstood the PCR process without any leakage. This study represents a significant step towards the practical application of on-chip DNA extraction methods, as well as the development of fully integrated genetic analytical systems.
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Celastrol may have an anti-atherosclerosis effect in a rabbit experimental carotid atherosclerosis model.
Int J Clin Exp Med
PUBLISHED: 07-15-2014
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Celastrol may have an anti-atherosclerosis effect. This study aimed to investigate if celastrol had an anti-AS effect using a rabbit experimental carotid atherosclerosis model.
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Development of PEA-15 using a potent non-viral vector for therapeutic application in breast cancer.
Cancer Lett.
PUBLISHED: 07-14-2014
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Advanced breast cancer requires systemic treatment, therefore developing an efficient and safe strategy is urgently needed. To ensure the success of target therapy, we have developed a breast cancer-specific construct (T-VISA) composed of the human telomerase reverse transcriptase (hTERT; T) promoter and a versatile transgene amplification vector VISA (VP16-GAL4-WPRE integrated systemic amplifier) to target PEA-15 (Phosphoprotein enriched in astrocytes) in advanced breast tumors. PEA-15 contains a death effector domain that sequesters extracellular signal-regulated kinase (ERK) in cytoplasm, thereby inhibiting cell proliferation and inducing apoptosis. T-VISA-PEA-15 was found to be highly specific, selectively express PEA-15 in breast cancer cells, and induce cancer-cell killing in vitro and in vivo without affecting normal cells. Moreover, intravenously treatment with T-VISA-PEA-15 coupled with liposome nanoparticles attenuated tumor growth and prolonged survival in mice bearing advanced breast tumors. Importantly, there was virtually no severe toxicity when PEA-15 is expressed by our T-VISA system compared with cytomegalovirus (CMV) promoter. Thus, our findings demonstrate an effective cancer-targeted therapy that is worthy of development in clinical trials eradicating advanced breast cancer.
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HBV preS2 transactivates FOXP3 expression in malignant hepatocytes.
Liver Int.
PUBLISHED: 07-11-2014
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Recent data reported the increased expression of forkhead box protein 3 (FOXP3), the well known master regulator of CD4(+) C25(+) regulatory T cells, in hepatocellular carcinoma (HCC) cells. However, the mechanisms remain unknown. We previously showed that preS2, one of important regulatory proteins encoded by HBV, triggers transactivation of hTERT in malignant hepatocytes. Here, we aimed to explore the role of preS2 in regulating FOXP3 expression in HCC.
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Combined effects of Fenton peroxidation and CaO conditioning on sewage sludge thermal drying.
Chemosphere
PUBLISHED: 06-27-2014
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Joint application of Fenton's reagent and CaO can dramatically enhance sludge dewaterability, thus are also likely to affect subsequent thermal drying process. This study investigated the synergistic effects of the two conditioners on the thermal drying behavior of sewage sludge and the emission characteristics of main sulfur-/nitrogen-containing gases. According to the results, Fenton peroxidation combined with CaO conditioning efficiently promoted sludge heat transfer, reduced the amounts of both free and bound water, and created porous structure in solids to provide evaporation channels, thus producing significant positive effects on sludge drying performance. In this case, the required time for drying was shortened to one-third. Additionally, joint usage of Fenton's reagent and CaO did not increase the losses of organic matter during sludge drying process. Meanwhile, they facilitated the formation of sulfate and sulfonic acid/sulfone, leading to sulfur retention in dried sludge. Both of Fenton peroxidation and CaO conditioning promoted the oxidation, decomposition, and/or dissolution of protein and inorganic nitrogen in sludge pre-treatment. As a consequence, the emissions of sulfurous and nitrogenous gases from dewatered sludge drying were greatly suppressed. These indicate that combining Fenton peroxidation with CaO conditioning is a promising strategy to improve drying efficiency of sewage sludge and to control sulfur and nitrogen contaminants during sludge thermal drying process.
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Effects of benthic macrofauna bioturbation on the bacterial community composition in lake sediments.
Can. J. Microbiol.
PUBLISHED: 06-26-2014
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Benthic macrofauna are considered to be an important part of the lacustrine ecosystem, and bioturbation may greatly affect the biogeochemical processes and microbial activities in sediments. In the present study, the bacterial community composition in sediments inhabited by 3 different types of benthic macrofauna (Corbicula fluminea, Chironomidae larvae, and tubificid worms) in the shallow and eutrophic Lake Taihu was studied to investigate the different effects of bioturbation on the composition of these communities. Microcosms were constructed, and culture-independent methods, including terminal restriction fragment length polymorphism (T-RFLP) and clone library analysis, were performed to evaluate the bacterial communities. Analysis of similarities (ANOSIM) and multidimensional scaling (MDS) analysis of T-RFLP patterns demonstrated that differences in the bacterial community composition between the control and the macrofauna-inhabited sediments were not as great as expected, although the chemical properties of the sediments changed remarkably. Nevertheless, the dominant bacterial group in each type of macrofauna-inhabited sediment was different. Acidobacteria, Betaproteobacteria, and Deltaproteobacteria were the dominant bacterial groups in sediments inhabited by C. fluminea, tubificid worms, and Chironomidae larvae, respectively. The data obtained in this study are helpful for understanding the effects of bioturbation in a shallow, eutrophic lake.
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Optimization of Rutaecarpine as ABCA1 Up-Regulator for Treating Atherosclerosis.
ACS Med Chem Lett
PUBLISHED: 06-24-2014
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ATP-binding cassette transporter A1 (ABCA1) is a key transporter and receptor in promoting cholesterol efflux, and increasing the expression level of ABCA1 is antiatherogenic. In our previous study, rutaecarpine (RUT) was found to protect ApoE(-/-) mice from developing atherosclerosis through preferentially up-regulating ABCA1 expression. In the present work, a series of RUT derivatives were synthesized and examined as ABCA1 expression up-regulators. Compounds CD1, CD6, and BCD1-2 were found to possess the most potential activity as antiatherosclerotic agents among all compounds tested.
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Liver X receptor activation protects against inflammation and enhances autophagy in myocardium of neonatal mouse challenged by lipopolysaccharides.
Biosci. Biotechnol. Biochem.
PUBLISHED: 06-12-2014
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Liver X receptors (LXRs) has been emerged as negative regulators of cardiomyocytic inflammation. The cellular process of autophagy is believed to play a protective role in myocardium during the inflammatory status. In this study, we investigated the role of LXRs agonist TO901317 (TO) on lipopolysaccharides (LPS)-induced myocardial inflammation and autophagy. The results showed that TO pretreatment significantly reduced the LPS-induced infiltration of inflammatory cells, elevation of NF-?B protein, TNF-?, and IL-6 mRNA levels in the myocardium. Moreover, LPS stimulated autophagy in neonatal mice heart, and this effect was further enhanced by TO pretreatment as evidenced by increased LC3-II/GAPDH ratio increment. Furthermore, TUNEL assay revealed LPS stimulation also increased the number of apoptotic cells in the myocardium, and the increment was inhibited by TO pretreatment. Our findings suggested that attenuation of inflammation and apoptosis, and enhancement of autophagy by TO may contribute to the protection of myocardium under inflammatory condition.
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Association of Gestational Diabetes Mellitus (GDM) with subclinical atherosclerosis: a systemic review and meta-analysis.
BMC Cardiovasc Disord
PUBLISHED: 06-11-2014
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Gestational diabetes mellitus (GDM) is associated with an elevated risk of adverse health outcomes such as type 2 diabetes and cardiovascular diseases. Carotid intima-media thickness (cIMT) is increasingly used as a noninvasive marker for subclinical atherosclerosis. Whether there is a direct correlation between GDM and elevated cIMT is still controversial.
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p204-mediated innate antiviral responses in mouse adipose cells and their effects on cell functions.
Immunol. Cell Biol.
PUBLISHED: 06-09-2014
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Viruses can infect adipose tissues. However, innate antiviral responses in adipose cells and their effects on adipocyte function have not yet been intensively investigated. In this study, p204-initiated innate antiviral responses in mouse adipose cells were examined. Cytosolic DNA sensor p204 and its signaling adaptor stimulator of interferon (IFN) genes (STING) were constitutively expressed in primary preadipocytes. Synthetic herpes simplex viral DNA (HSV60), a p204 ligand, induced type I IFN expression by activating IFN regulatory factor 3. Major antiviral proteins, including IFN-stimulating gene 15, 2',5'-oligoadenylate synthetase and Mx GTPase 1, in preadipocytes were upregulated by HSV60. HSV60-triggered innate antiviral responses were significantly reduced by inhibition of p204 signaling with specific small interfering RNA targeting p204 or STING. HSV60 inhibited the differentiation of preadipocytes to mature adipocytes and enhanced the proliferation of adipose cells. Moreover, HSV60 induced innate antiviral responses in mature adipocytes and inhibited expressions of several adipokines, including leptin, adiponectin and resistin. These results indicated that p204 initiated innate antiviral responses in adipose cells, thereby modulating adipocyte function.Immunology and Cell Biology advance online publication, 7 October 2014; doi:10.1038/icb.2014.83.
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High-efficiency all-polymer solar cells based on a pair of crystalline low-bandgap polymers.
Adv. Mater. Weinheim
PUBLISHED: 06-03-2014
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All-polymer solar cells based on a pair of crystalline low-bandgap polymers (NT and N2200) are demonstrated to achieve a high short-circuit current density of 11.5 mA cm-2 and a power conversion efficiency of up to 5.0% under the standard AM1.5G spectrum with one sun intensity. The high performance of these NT:N2200-based cells can be attributed to the low optical bandgaps of the polymers and the reasonably high and balanced electron and hole mobilities of the NT:N2200 blends due to the crystalline nature of the two polymers.
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Hepatitis E virus infection in farmed rabbits and swine in the Eastern Chinese city Lianyungang: showing no potential interspecies transmission.
J. Med. Virol.
PUBLISHED: 05-30-2014
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Rabbit HEV isolated recently from farmed rabbits in China has been shown experimentally to be able to infect both cynomolgus macaques and pigs. The purpose of the present study was to investigate the extent to which cross-species transmission of rabbit HEV in farm settings is a significant factor in the spread of this zoonotic infection. Rabbit and swine feces were collected from the same area in Eastern China (Lianyungang City) and analyzed by RT-PCR. Partial genome sequencing of a 365?bp region of ORF2 from the HEV positive rabbit samples revealed that they had 92-99% sequence identity with rabbit strains (rbIM163-c1 and rbIM004) isolated from Inner Mongolia. Similarly, sequencing of a 765?bp region of ORF2 of HEV positive swine samples showed 96-98% sequence identity with genotype 4d isolates collected from patients in the Yantai and Nanjing regions of China. By contrast, the sequence identity between the rabbit and swine isolates was only 73-75%, with no molecular biological evidence of interspecies transmission having occurred. It is concluded that whilst interspecies infection with rabbit HEV can be achieved experimentally, in the field it is not a significant factor in zoonotic disease transmission at least in the area of China where this study was undertaken.
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Long-term risk of late and very late stent thrombosis in patients treated with everolimus against paclitaxel-eluting stents: an updated meta-analysis.
Coron. Artery Dis.
PUBLISHED: 05-14-2014
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Everolimus-eluting stent (EES) reduces the risk of late and very late stent thrombosis (ST) in a number of randomized controlled trials (RCTs). However, the benefits have been variable.
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The prognostic utility and the association of serum light chains (free and total) and absolute lymphocyte count in patients with newly diagnosed diffuse large B-cell lymphoma.
Leuk. Res.
PUBLISHED: 05-06-2014
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In this study, serum free and total light chains (sFLC/sTLC) were measured in 108 serum samples of therapy-naïve patients with DLBCL. Clinicopathologic data and survival outcomes were analyzed according to the results of sFLC/sTLC measurements. Moreover, the association of sFLC/sTLC with absolute monocyte count (AMC) and absolute lymphocyte count (ALC) was evaluated. Elevated sFLC and abnormal ?/? ratio was present in 42.6% (51/108) and 4.6% (5/108) of patients, respectively. sTLC was successfully measured in 107 serum samples, abnormal sTLC and abnormal ?/? ratio was found in 28.0% (30/107) and 26.2% (28/107) of patients, respectively. Patients with elevated sFLC more frequently displayed adverse clinical characteristics, including age (P=0.001), B symptoms (P=0.022), low ALC (P=0.024) and hyperglobulinemia (P=0.012). Patients with elevated sFLC had an inferior overall survival (OS) (P=0.012) and tended to have shorter progression-free survival (PFS) (P=0.061) compared to patients with normal sFLC. Abnormal sTLC or abnormal sTLC ratio showed no significant association with clinical outcomes, with exception of abnormal concurrent ? and ?. Only association of sFLC and ALC with survival remained significant after adjusting for the International Prognostic Index (IPI). The measurement of sFLC and ALC at diagnosis might be useful for the prognostic stratification of patients and sTLC measurement was of little prognostic utility in DLBCL.
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Inhibitory mechanisms in single negative priming from ignored and briefly flashed primes: The key role of the inter-stimulus interval.
Conscious Cogn
PUBLISHED: 05-06-2014
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The influence of interstimulus intervals (ISIs) on priming effects was investigated using a single-prime negative priming (NP) paradigm. In all experiments, a brief (16ms), centrally displayed prime (a Chinese character, to be ignored) appeared, followed by a pattern mask and then a centrally displayed target (another semantically related or unrelated Chinese character); the task required semantic categorization (animate/inanimate) of the target. An ISI could occur either between prime and mask (Experiments 1 and 5) or between mask and target (Experiments 2-4). The results revealed NP when a 470ms ISI occurred between prime and mask (Experiments 1 and 5) and when a 700ms ISI occurred between mask and target (Experiments 3 and 4). In contrast, when a long prime-target SOA was maintained but the mask-target ISI was shortened, NP disappeared (Experiment 4). The results indicated that a persisting mask/distractor (without ISI) located in the same position as the following target interfered with the buildup of inhibition, but an ISI between prime and mask or mask and target eliminated this interference, and that inhibition processes induced by an ignore instruction were implemented faster with an ISI placed between prime and mask than with an ISI placed between mask and target.
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Research on key factors and their interaction effects of electromagnetic force of high-speed solenoid valve.
ScientificWorldJournal
PUBLISHED: 05-03-2014
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Analysis consisting of numerical simulations along with lab experiments of interaction effects between key parameters on the electromagnetic force based on response surface methodology (RSM) has been also proposed to optimize the design of high-speed solenoid valve (HSV) and improve its performance. Numerical simulation model of HSV has been developed in Ansoft Maxwell environment and its accuracy has been validated through lab experiments. Effect of change of core structure, coil structure, armature structure, working air gap, and drive current on the electromagnetic force of HSV has been analyzed through simulation model and influence rules of various parameters on the electromagnetic force have been established. The response surface model of the electromagnetic force has been utilized to analyze the interaction effect between major parameters. It has been concluded that six interaction factors including working air gap with armature radius, drive current with armature thickness, coil turns with side pole radius, armature thickness with its radius, armature thickness with side pole radius, and armature radius with side pole radius have significant influence on the electromagnetic force. Optimal match values between coil turns and side pole radius; armature thickness and side pole radius; and armature radius and side pole radius have also been determined.
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Versatile on-demand droplet generation for controlled encapsulation.
Biomicrofluidics
PUBLISHED: 05-01-2014
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We present a droplet-based microfluidic system for performing bioassays requiring controlled analyte encapsulation by employing highly flexible on-demand droplet generation. On-demand droplet generation and encapsulation are achieved pneumatically using a microdispensing pump connected to a constant pressure source. The system generates single droplets to the collection route only when the pump is actuated with a designated pressure level and produces two-phase parallel flow to the waste route during the stand-by state. We analyzed the effect of actuation pressure on the stability and size of droplets and optimized conditions for generation of stable droplets over a wide pressure range. By increasing the duration of pump actuation, we could either trigger a short train of identical size droplets or generate a single larger droplet. We also investigated the methodology to control droplet contents by fine-tuning flow rates or implementing a resistance bridge between the pump and main channels. We demonstrated the integrated chip for on-demand mixing between two aqueous phases in droplets and on-demand encapsulation of Escherichia coli cells. Our unique on-demand feature for selective encapsulation is particularly appropriate for bioassays with extremely dilute samples, such as pathogens in a clinical sample, since it can significantly reduce the number of empty droplets that impede droplet collection and subsequent data analysis.
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Pancreaticogastrostomy versus pancreaticojejunostomy reconstruction after pancreaticoduodenectomy: a meta-analysis of randomized controlled trials.
Surg. Today
PUBLISHED: 04-30-2014
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We conducted this meta-analysis to establish whether pancreaticogastrostomy (PG) or pancreaticojejunostomy (PJ) is the better method of reconstruction for reducing the risk of postoperative pancreatic fistula (POPF).
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Clinical features, survival and prognostic factors of primary testicular diffuse large B-cell lymphoma.
Chin. J. Cancer Res.
PUBLISHED: 04-24-2014
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To assess the clinical features, survival and prognostic factors of primary testicular diffuse large B-cell lymphoma (DLBCL).
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miR-22 as a prognostic factor targets glucose transporter protein type 1 in breast cancer.
Cancer Lett.
PUBLISHED: 04-21-2014
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It has been reported that miR-22 plays an important role and may be a promising therapeutic target in cancer. In this study, we found that GLUT1 is a direct target of miR-22. The ectopic expression of miR-22 inhibited breast cancer cell proliferation and invasion by targeting GLUT1. A reverse correlation between the expression of miR-22 and GLUT1 was observed in breast cancer tissue samples. Furthermore, miR-22 was significantly correlated with the TNM stage, local relapse, distant metastasis, and survival of breast cancer patients. Our data suggest that miR-22 functions as a tumor suppressor and is a promising prognostic biomarker in breast cancer.
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The latest progress in research on triple negative breast cancer (TNBC): risk factors, possible therapeutic targets and prognostic markers.
J Thorac Dis
PUBLISHED: 04-14-2014
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Triple negative breast cancer (TNBC) is one type of breast cancer (BC), which is defined as negative for estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (Her2). Its origins and development seem to be elusive. And for now, drugs like tamoxifen or trastuzumab which specifically apply to ER, PR or Her2 positive BC seem unforeseeable in TNBC clinical treatment. Due to its extreme malignancy, high recurrence rate and poor prognosis, a lot of work on the research of TNBC is needed. This review aims to summarize the latest findings in TNBC in risk factors, possible therapeutic targets and possible prognostic makers.
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Comparative analyses of C4 and C3 photosynthesis in developing leaves of maize and rice.
Nat. Biotechnol.
PUBLISHED: 04-12-2014
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C4 and C3 photosynthesis differ in the efficiency with which they consume water and nitrogen. Engineering traits of the more efficient C4 photosynthesis into C3 crops could substantially increase crop yields in hot, arid conditions. To identify differences between C4 and C3 photosynthetic mechanisms, we profiled metabolites and gene expression in the developing leaves of Zea mays (maize), a C4 plant, and Oryza sativa (rice), a C3 plant, using a statistical method named the unified developmental model (UDM). Candidate cis-regulatory elements and transcription factors that might regulate photosynthesis were identified, together with differences between C4 and C3 nitrogen and carbon metabolism. The UDM algorithms could be applied to analyze and compare development in other species. These data sets together with community viewers to access and mine them provide a resource for photosynthetic research that will inform efforts to engineer improvements in carbon fixation in economically valuable grass crops.
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Development of a liquid chromatography-mass spectrometry method for determination of agrimol B in rat plasma: application to preclinical pharmacokinetics.
Biomed. Chromatogr.
PUBLISHED: 03-30-2014
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A sensitive and accurate liquid chromatography coupled with mass spectrometry (LC-MS) method was developed for the determination of agrimol B, a main active ingredient isolated from Agrimonia pilosa Ledeb., in rat plasma. Chromatographic separation was achieved on a Zorbax CN column (150?×?4.6?mm, 5?µm), with isocratic elution consisting of acetonitrile and water (15:85, v/v) at a flow rate of 0.6?mL/min. Agrimol B and dryocrassin ABBA, an internal standard (IS), were analyzed by selected ion monitoring at m/z transitions of 681.3 and 819.4, respectively. This assay exhibited a good linearity with a correlation coefficient >0.99 and showed no endogenous interference with the analyte and IS. The limit of quantification of agrimol B was 8.025?ng/mL with acceptable precision and accuracy. The method was successfully applied in the pharmacokinetic study of agrimol B in rats after intravenous (1?mg/kg) and oral (2, 5 and 10?mg/kg) doses of agrimol B. The absolute bioavailability of agrimol B was 16.4-18.0% in rat. Our study clarifies the pharmacokinetic behavior of agrimol B in animals. Copyright © 2014 John Wiley & Sons, Ltd.
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Identification of candidate genes JcARF19 and JcIAA9 associated with seed size traits in Jatropha.
Funct. Integr. Genomics
PUBLISHED: 03-23-2014
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Jatropha curcas is a new promising bioenergy crop due to the high oil content in its seeds that can be converted into biodiesel. Seed size, a major determinant of Jatropha oil yield, is a target trait for Jatropha breeding. Due to the vital roles of phytohormone auxin in controlling seed and fruit development, we screened key genes in auxin pathway including ARF and IAA families and downstream effectors to identify candidate genes controlling seed size in Jatropha. As a result, JcARF19 was mapped in the major quantitative trait locus (QTL) region and significantly associated with seed length. By using expression QTL (eQTL) analysis to link variants with functional candidate genes, we provided evidences that seed traits were affected by the interaction of JcARF19 and JcIAA9. ARF19 and IAA9, involved in auxin signal transduction, were conserved in higher plants. These data including the single-nucleotide polymorphisms (SNPs) in the two genes could lead to utilization of the genes by integrating favored alleles into elite varieties through marker-assisted selection.
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Phase I clinical trial of pegylated liposomal mitoxantrone plm60-s: pharmacokinetics, toxicity and preliminary efficacy.
Cancer Chemother. Pharmacol.
PUBLISHED: 03-22-2014
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Plm60-s is a pegylated liposomal mitoxantrone formulation, in which mitoxantrone was loaded into small unilamellar vesicles (~60 nm) made from solid lipid membrane. This two-arm, dose-escalating phase I study was designed to determine safety and pharmacokinetics of plm60-s, and to compare with those of conventional mitoxantrone injection (c-MI).
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Differential efficacy of subtalar fusion with three operative approaches.
J Orthop Surg Res
PUBLISHED: 03-21-2014
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BackgroundThere are many existing operative approaches for subtalar fusion; however, no optional strategy of operative approach has been developed yet. This study aimed to analyze the differential clinical efficacy of subtalar fusion with three operative approaches.MethodsThe clinical data of 102 patients from April 2008 to April 2012 were analyzed prospectively. These patients were divided into three groups with the random number table: group A, group B, and group C. The following parameters were compared among three groups: effective exposure area and exposure time of subtalar joint, intraoperative bleeding volume, postoperative complications, fusion time, fusion rate, AOFAS score and VAS score before and after operation.ResultsIn the exposure area score, there was no statistically significant difference between group A and group C (P >0.05) ,but with a statistically significant difference between group A/C and group B (P <0.05). In exposure time and intraoperative bleeding volume, there was no statistically significant difference between group A and group B (P >0.05) but with a statistically significant difference between group A/B and group C (P <0.05). In three groups, there was a statistically significant difference in both AOFAS score and VAS score before operation and at 6 months/12 months/last visit after operation (P <0.05). The incidence of complications in the three groups was 8.8%, 12.5% and 19.4%. No statistically significant differences in fusion rate and fusion time were observed among the three groups (P >0.05).ConclusionThree operative approaches have different indications, All the three operative approaches do not influence the fusion rate and fusion time of subtalar joint. The lateral tarsal sinus approach is inferior to the posterior-lateral L approach and the approach from the inferior tip of fibula to the basilar part of the fourth metatarsal bone in the exposure area, while the lateral tarsal sinus approach and the approach from the inferior tip of fibula to the basilar part of the fourth metatarsal bone are superior to the posterior-lateral L approach in the exposure time, intraoperative bleeding volume, and incidence of complications.Level of evidenceTherapeutic, level III.
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A bioorthogonal small-molecule-switch system for controlling protein function in live cells.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 03-19-2014
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Chemically induced dimerization (CID) has proven to be a powerful tool for modulating protein interactions. However, the traditional dimerizer rapamycin has limitations in certain in?vivo applications because of its slow reversibility and its affinity for endogenous proteins. Described herein is a bioorthogonal system for rapidly reversible CID. A novel dimerizer with synthetic ligand of FKBP' (SLF') linked to trimethoprim (TMP). The SLF' moiety binds to the F36V mutant of FK506-binding protein (FKBP) and the TMP moiety binds to E. coli dihydrofolate reductase (eDHFR). SLF'-TMP-induced heterodimerization of FKBP(F36V) and eDHFR with a dissociation constant of 0.12??M. Addition of TMP alone was sufficient to rapidly disrupt this heterodimerization. Two examples are presented to demonstrate that this system is an invaluable tool, which can be widely used to rapidly and reversibly control protein function in vivo.
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Reduced nucleic ZHX2 involves in oncogenic activation of glypican 3 in human hepatocellular carcinoma.
Int. J. Biochem. Cell Biol.
PUBLISHED: 03-16-2014
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Glypican 3 (GPC3) has been paid particular attention owing to its potential as diagnosis marker for hepatocellular carcinoma (HCC). Identifying the mechanisms regulating the reactivation of GPC3 in HCC appears to be clinically meaningful. Previous study identified zinc-fingers and homeoboxes 2 (ZHX2) as transcriptional factor responsible for postnatal repression of GPC3 in mice. Here, in this study, we provided the first evidence that down regulated ZHX2 is responsible for GPC3 reactivation in HCC. First, inverse correlation of ZHX2 with GPC3 expression was shown in cultured liver cell lines. Second, ZHX2 overexpression significantly decreased GPC3 expression, while ZHX2 knockdown effectively increased GPC3 level in different HCC cell lines. Consistently, dual luciferase and ChIP assay showed that ZHX2 dose-dependently suppressed GPC3 promoter activity by binding with the core promoter. More importantly, immunohistochemical staining demonstrated the inverse correlation between nuclear ZHX2 with GPC3 expression in HCC tissues. Further in vitro analysis showed that nuclear translocation was crucial for ZHX2 mediated repression on GPC3 transcription. Taken together, our results prove that ZHX2 suppresses GPC3 transcription by binding with its core promoter and reduced nucleic ZHX2 expression may be involved in GPC3 reactivation in HCC.
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Lactobacillus plantarum NDC 75017 alleviates the learning and memory ability in aging rats by reducing mitochondrial dysfunction.
Exp Ther Med
PUBLISHED: 03-11-2014
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The aim of the present study was to investigate the protective effect of Lactobacillus plantarum NDC 75017 on D-galactose (D-gal)-induced mitochondrial dysfunction in the rat cerebral cortex. Fifty rats were randomly divided into five groups (n=10 in each group). The rats in the aging model group were subcutaneously injected with 100 mg/kg D-gal and those in the protective groups were additionally orally administered L. plantarum NDC 75017 at doses of 1×10(8), 1×10(9) or 1×10(10) CFU/100 mg body weight/day, respectively. The control rats were administrated an equal volume of the vehicle. Following continuous treatment for seven weeks, the learning and memory abilities and mitochondrial ultrastructure, function and adenosine triphosphate (ATP) levels were examined. The results showed that the learning and memory abilities and mitochondrial levels of ATP were significantly decreased in the D-gal-induced aging model group compared with those in the control group (P<0.01). In addition, marked changes in the mitochondrial functions and ultrastructure were observed between the groups. Seven weeks of L. plantarum NDC 75017 and D-gal coadministration significantly improved the learning and memory abilities of the rats compared with the D-gal-induced aging model group. Furthermore, the combination regime significantly improved the mitochondrial ultrastructure and functions, including the mitochondrial respiratory chain, mitochondrial membrane potential and mitochondrial permeability transition. The results revealed that the L. plantarum NDC 75017 was able to alleviate learning and memory injuries in aging rats by reducing the mitochondrial dysfunction induced by D-gal.
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Perceptual and motor contributions to the negative compatibility effect.
Acta Psychol (Amst)
PUBLISHED: 02-24-2014
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The current study focused on contributions to the negative compatibility effect (NCE) from object-updating at the perceptual level and self-inhibition (i.e., automatic motor inhibition) at the response (motor) level. We hypothesized that contributions to the NCE from these two levels were moderated by the strength of stimulus and reaction (S-R) link: object-updating should have greater impact on the NCE with weak S-R links, but both object-updating and self-inhibition should impact on the NCE when the S-R links became strong. To test this hypothesis, in two experiments we used a novel type of stimuli and manipulated mask relevance (relevant versus irrelevant mask) and prime/target compatibility. Participants performed two tasks over three successive days. Results showed that under equivalent masking effectiveness between the two conditions of mask, a significant NCE was observed only in the relevant mask condition when the S-R links were weak, but both close to equal NCE sizes were observed in the two mask conditions when the S-R links were acquired through practice. The results indicated that perceptual and motor contributions to the NCE were moderated by the strength of S-R links, if the strength of the links was too weak to trigger the following inhibition, the NCE primarily originated from object-updating at the perceptual level; if the strength of the links was reinforced by practice, which exceeded the inhibitory threshold, the NCE originated from both object-updating and self-inhibition, but the latter was primarily responsible.
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Novel biocompatible pH-stimuli responsive superparamagnetic hybrid hollow microspheres as tumor-specific drug delivery system.
Colloids Surf B Biointerfaces
PUBLISHED: 02-17-2014
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Novel biocompatible pH-stimuli responsive superparamagnetic hybrid hollow microspheres have been designed via the layer-by-layer (LbL) self-assembly technique via the electrostatic interaction between the poly(ethylene glycol) grafted chitosan (CS-g-PEG) as polycation and the citrate modified ferroferric oxide nanoparticles (Fe3O4-CA) as hybrid anion onto the uniform polystyrene sulfonate (PSS) microsphere templates. The well-defined hybrid hollow microspheres ((CS-g-PEG/Fe3O4-CA)4/CS-g-PEG) were obtained after etching the templates by washing with DMF. They possessed superparamagnetic characteristics with a saturation magnetization of 37.23emu/g, and exhibited excellent stability in high ion-strength media and pH dependent DOX release. Their unique structure and outstanding performance make them potential platform for tumor-specific delivery in the tumor diagnostic and therapy.
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The second dorsal metacarpal artery chain-link flap: an anatomical study and a case report.
Surg Radiol Anat
PUBLISHED: 01-22-2014
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The purpose of this study was to discuss the distribution characteristics and the anatomical angioarchitecture of cutaneous branches arising from the second dorsal metacarpal artery for the repair of small tissue defects in the hand or fingers using the second dorsal metacarpal artery chain-link flap.
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Easily manageable prognostic factors in 152 Chinese elderly acute myeloid leukemia patients: a single-center retrospective study.
J Biomed Res
PUBLISHED: 01-11-2014
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We retrospectively investigated the prognostic factors of acute myeloid leukemia (AML) in 152 Chinese patients with de novo AML who were older than 60 years of age and who received treatment at our hospital. Log-rank test showed that 6 parameters including older age, higher white blood cell (WBC) counts, lactate dehydrogenase (LDH) and bone marrow (BM) blasts at diagnosis, unfavorable risk cytogenetics, and non-mutated CEBP? were significant adverse prognostic factors of overall survival (OS) for elderly AML patients (P ?=? 0.0013, 0.0358, 0.0132, 0.0242, 0.0236 and 0.0130, respectively). Moreover, older age and higher LDH were significant adverse predictors for relapse-free survival (RFS) (P ?=? 0.0447 and 0.0470, respectively). Univariate analysis revealed similar results for OS to those of the log-rank test and only higher LDH at diagnosis was a significant adverse predictor for RFS (P ?=? 0.028, HR: 1.979, 95%CI: 1.075-3.644). In multivariate analysis, we identified 2 trends towards independent prognostic factors for OS, including BM blasts at diagnosis (P ?=? 0.057, HR: 1.676, 95%CI: 0.984-2.854) and mutation status of CEBP? (P ?=? 0.064, HR: 4.173, 95%CI: 0.918-18.966). Our data indicated that older age, gender and a previous history of hematologic diseases resulted in lower complete remission rate (P ?=? 0.012, 0.051 and 0.086, respectively). We further developed an easy scoring system for predicting prognosis and response to induction therapy in older AML patients. Patients who had lower scores showed significantly longer OS and RFS (P ?=? 0.0006 and 0.1001, respectively) and higher CR rate (P ?=? 0.014). Our research is limited by its retrospective nature and the results from our study need to be further validated by prospective randomized clinical trials.
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Diallyl Disulfide Suppresses SRC/Ras/ERK Signaling-Mediated Proliferation and Metastasis in Human Breast Cancer by Up-Regulating miR-34a.
PLoS ONE
PUBLISHED: 01-01-2014
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Diallyl disulfide (DADS) is one of the major volatile components of garlic oil. DADS has various biological properties, including anticancer, antiangiogenic, and antioxidant effects. However, the anticancer mechanisms of DADS in human breast cancer have not been elucidated, particularly in vivo. In this study, we demonstrated that the expression of miR-34a was up-regulated in DADS-treated MDA-MB-231 cells. miR-34a not only inhibited breast cancer growth but also enhanced the antitumor effect of DADS, both in vitro and in vivo. Furthermore, Src was identified as a target of miR-34a, with miR-34a inhibiting SRC expression and consequently triggering the suppression of the SRC/Ras/ERK pathway. These results suggest that DADS could be a promising anticancer agent for breast cancer. miR-34a may also demonstrate a potential gene therapy agent that could enhance the antitumor effects of DADS.
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Advanced oxidation of hypophosphite and phosphite using a UV/H2O2 process.
Environ Technol
PUBLISHED: 12-20-2013
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The oxidation of hypophosphite and phosphite in an aqueous solution by an ultraviolet (UV)/H2O2 process was studied in this work. The reactions were performed in a lab-scale batch photoreactor. The effect of different parameters such as H2O2 dosage, H2O2 feeding mode and the initial pH of the solution on the oxidation efficiency of the process was investigated. The results indicated that the UV/H2O2 process could effectively oxidize hypophosphite and phosphite in both synthesized and real wastewater. However, neither H2O2 nor UV alone was able to appreciably oxidize the hypophosphite or phosphite. The best way of feeding H2O2 was found to be continuous feeding, which maximized the reaction rate. It was also found that the process presented a wide range of applicable initial pH (5-11). When treating real rinse-wastewater, which was obtained from the electroless nickel plating industry, both hypophosphite and phosphite were completely oxidized within 60 min, and by extending by another 30 min, over 90% of the chemical oxygen demand removal was obtained. Without any additional catalyst, the UV/H2O2 process can oxidize hypophosphite and phosphite to easily removable phosphate. It is really a powerful and environmentally friendly treatment method for the wastewater containing hypophosphite and phosphite.
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Palladium-Catalyzed Meta-Selective C-H Bond Activation with a Nitrile-Containing Template: Computational Study on Mechanism and Origins of Selectivity.
J. Am. Chem. Soc.
PUBLISHED: 12-17-2013
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Density functional theory investigations have elucidated the mechanism and origins of meta-regioselectivity of Pd(II)-catalyzed C-H olefinations of toluene derivatives that employ a nitrile-containing template. The reaction proceeds through four major steps: C-H activation, alkene insertion, ?-hydride elimination, and reductive elimination. The C-H activation step, which proceeds via a concerted metalation-deprotonation (CMD) pathway, is found to be the rate- and regioselectivity-determining step. For the crucial C-H activation, four possible active catalytic species-monomeric Pd(OAc)2, dimeric Pd2(OAc)4, heterodimeric PdAg(OAc)3, and trimeric Pd3(OAc)6-have been investigated. The computations indicated that the C-H activation with the nitrile-containing template occurs via a Pd-Ag heterodimeric transition state. The nitrile directing group coordinates with Ag while the Pd is placed adjacent to the meta-C-H bond in the transition state, leading to the observed high meta-selectivity. The Pd2(OAc)4 dimeric mechanism also leads to the meta-C-H activation product but with higher activation energies than the Pd-Ag heterodimeric mechanism. The Pd monomeric and trimeric mechanisms require much higher activation free energies and are predicted to give ortho products. Structural and distortion energy analysis of the transition states revealed significant effects of distortions of the template on mechanism and regioselectivity, which provided hints for further developments of new templates.
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Spectral modulation of high-order harmonic generation from prealigned CO2 molecules.
Opt Lett
PUBLISHED: 12-11-2013
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We demonstrate experimentally that prealigned molecules produce observable spectral redshift or blueshift on the high-order harmonic generation. We distinguish two effects of molecular alignment on the phase modulation of the harmonics; one is from the gradient of alignment degree and the other is the plasma density varied by the molecular alignment. The finding provides an insight on the spectral distribution of molecular harmonics and a method of fine-tuning the harmonic spectrum.
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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.