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Find video protocols related to scientific articles indexed in Pubmed.
Quantitative Measurements of Vibration Amplitude Using a Contact-Mode Freestanding Triboelectric Nanogenerator.
ACS Nano
PUBLISHED: 11-12-2014
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A vibration sensor is usually designed to measure the vibration frequency but disregard the vibration amplitude, which is rather challenging to be quantified due to the requirement of linear response. Here, we show the application of triboelectric nanogenerator (TENG) as a self-powered tool for quantitative measurement of vibration amplitude based on an operation mode, the contact-mode freestanding triboelectric nanogenerator (CF-TENG). In this mode, the triboelectrically charged resonator can be agitated to vibrate between two stacked stationary electrodes. Under the working principle with a constant capacitance between two electrodes, the amplitudes of the electric signals are proportional to the vibration amplitude of the resonator (provided that the resonator plate is charged to saturation), which has been illuminated both theoretically and experimentally. Together with its capability in monitoring the vibration frequency, the CF-TENG appears as the triboelectrification-based active sensor that can give full quantitative information about a vibration. In addition, the CF-TENG is also demonstrated as a power source for electronic devices.
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[Epidemiological characteristics of typhoid fever and antibiotic susceptibility testing of Salmonella Typhi isolates in Guangxi, 1994-2013].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 11-08-2014
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Through analyzing the typhoid epidemics and to determine and monitor regional resistance characteristics of the shift of drug resistant profile on Salmonella (S.) Typhi, to understand the related epidemiological characteristics of typhoid fever and to provide evidence for the development of strategies, in Guangxi.
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[Study on HIV-1 related genetics and threshold on drug resistance in Dehong prefecture of Yunnan province in 2012].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 11-08-2014
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To study the HIV-1 genotypes and transmitted drug resistance (TDR) in Dehong prefecture of Yunnan province in 2012.
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Cell polarity protein CRB3 is an independent favorable prognostic factor for clear cell renal cell carcinoma.
Int. J. Oncol.
PUBLISHED: 09-16-2014
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Epithelial cells possess apical?basal polarity and loss of epithelial cell polarity contributes to tumorigenesis and cancer progression. The Crumbs (CRB) polarity protein plays a crucial role in epithelial polarity maintenance, apical membrane formation, and tissue morphogenesis. Although evidence is increasing on involvement of deregulated polarity proteins in cancers, little is currently known about the roles of the CRB (Drosophila), especially the roles of CRB3, a homolog of the CRB, in clear cell renal cell carcinoma (ccRCC). Studies have shown that CRB3 may act as a tumor suppressor in non?human mammalian cells; the study here was aimed to examine the expression status of CRB3 in ccRCC and the relationships between CRB3 expression and clinicopathologic parameters of ccRCC patients. Our results showed that CRB3 was weakly expressed in ccRCC tissues, but strongly expressed in adjacent normal kidney tissues. Patients with loss of CRB3 expression showed a significantly shorter overall survival (OS) than patients with positive CRB3 expression. Our results suggested that CRB3 may be an independent favorable prognostic factor for patients with ccRCC. We also found that overexpression of CRB3 restrained invasion and migration of 786?O cells and loss of CRB3 expression promoted invasion and migration of human embryonic kidney 293T (HEK 293T) cells. This finding may explain why the negative CRB3 expression was associated with poor prognosis in human ccRCC. Altogether, our data demonstrated that CRB3 may be used as a new independent favorable prognostic factor for human ccRCC.
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Loss of LKB1 disrupts breast epithelial cell polarity and promotes breast cancer metastasis and invasion.
J. Exp. Clin. Cancer Res.
PUBLISHED: 09-02-2014
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BackgroundLKB1, also known as STK11, is a master kinase that serves as an energy metabolic sensor and is involved in cell polarity regulation. Recent studies have indicated that LKB1 is related to breast tumorigenesis and breast cancer progression. However, little work has been done on the roles of LKB1 in cell polarity and epithelial-mesenchymal transition in breast cancer. In this study, we tried to prove that loss of LKB1 disrupts breast epithelial cell polarity and causes tumor metastasis and invasion.MethodsThe relationships of LKB1 expression to clinic-pathological parameters and epithelial markers E-cadherin and high-molecular-weight -cytokeratin (HMW-CK) were investigated in 80 clinical breast cancer tissue samples and their paired normal control breast tissue samples by using immunohistochemistry. Then, the LKB1 expressions in metastatic and non-metastatic breast cancer cell lines were compared. The roles of LKB1 in cell polarity and epithelial-mesenchymal transition in breast cancer were determined by using immunofluorescence, western blot assay, and cell migration and invasive assays. Finally, the non-transformed human breast cell line MCF-10A was cultured in three dimensions to further reveal the role of LKB1 in breast epithelial cell polarity maintenance.ResultsHistopathological analysis showed that LKB1 expression level was significantly negatively correlated with breast cancer TNM stage, and positively correlated with ER/PR status and expression levels of E-cadherin and HMW-CK. Immunofluorescence staining showed that LKB1 was co-localized with E-cadherin at adheren junctions. In vitro analysis revealed that loss of LKB1 expression enhanced migration, invasion and the acquisition of mesenchymal phenotype, while LKB1 overexpression in MDA-MB-435 s cells, which have a low basal level of LKB1 expression, promoted the acquisition of epithelial phenotype. Finally, it was found for the first time that endogenous LKB1 knockdown resulted in abnormal cell polarity in acini formed by non-transformed breast epithelial cells grown in 3D culture.ConclusionOur data indicated that low expression of LKB1 was significantly associated with established markers of unfavorable breast cancer prognosis, such as loss of ER/PR, E-cadherin and HMW-CK. Knockdown of endogenous LKB1 gave rise to dysregulation of cell polarity and invasive phenotype of breast cancer cells.
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In-line phase-contrast imaging based on Tsinghua Thomson scattering x-ray source.
Rev Sci Instrum
PUBLISHED: 09-01-2014
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Thomson scattering x-ray sources can produce ultrashort, energy tunable x-ray pulses characterized by high brightness, quasi-monochromatic, and high spatial coherence, which make it an ideal source for in-line phase-contrast imaging. We demonstrate the capacity of in-line phase-contrast imaging based on Tsinghua Thomson scattering X-ray source. Clear edge enhancement effect has been observed in the experiment.
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Rosuvastatin reduces ischemia-reperfusion injury in patients with acute coronary syndrome treated with percutaneous coronary intervention.
Clin Cardiol
PUBLISHED: 08-25-2014
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Statins reduce the incidence of cardiovascular events after percutaneous coronary intervention (PCI), but no clinical studies have investigated the role of statins in ischemia-reperfusion injury after PCI.
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Grating-structured freestanding triboelectric-layer nanogenerator for harvesting mechanical energy at 85% total conversion efficiency.
Adv. Mater. Weinheim
PUBLISHED: 08-25-2014
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A newly-designed triboelectric nanogenerator is demonstrated which is composed of a grating-segmented freestanding triboelectric layer and two groups of interdigitated electrodes with the same periodicity. The sliding motion of the grating units across the electrode fingers can be converted into multiple alternating currents through the external load due to the contact electrification and electrostatic induction. Working in non-contact mode, the device shows excellent stability and the total conversion efficiency can reach up to 85% at low operation frequency.
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A new library of arsine, stibine-stabilized N-heterocyclic carbene palladium complexes: synthesis, structures and activities in C-C and C-N coupling reactions.
Dalton Trans
PUBLISHED: 08-18-2014
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A series of new N-heterocyclic carbene palladium complexes bearing AsPh3 and SbPh3 functions PdCl2(IMes)(AsPh3) (1a), PdCl2(IMes)(SbPh3) (1b), PdCl2(IPr)(AsPh3) (1c), PdCl2(IPr)(SbPh3) (1d), PdCl2(SIMes)(AsPh3) (2a), PdCl2(SIMes)(SbPh3) (2b), PdCl2(SIPr)(AsPh3) (2c), and PdCl2(SIPr)(SbPh3) (2d) (IMes = N,N'-bis-(2,4,6-trimethylphenyl)imidazol-2-ylidene; IPr = N,N'-bis-(2,6-di(iso-propyl)phenyl)imidazol-2-ylidene; SIMes = N,N'-bis-(2,4,6-trimethylphenyl)imidazolidin-2-ylidene; SIPr = N,N'-bis-(2,6-di(iso-propyl)phenyl)imidazolidin-2-ylidene) was synthesized and fully characterized by (1)H NMR, (13)C NMR, and FT-IR spectroscopy, elemental analysis and single-crystal X-ray crystallography. The catalytic potential of these arsine and stibine-stabilized carbene palladium complexes for Pd-mediated transformations was investigated with various substrates in the Hiyama cross-coupling reactions and Buchwald-Hartwig aminations. The results demonstrate that these complexes show high catalytic activity and good tolerance to various chemical functions.
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Simultaneous measurements of cortisol and cortisone in urine and hair for the assessment of 11?-hydroxysteroid dehydrogenase activity among methadone maintenance treatment patients with LC-ESI-MS/MS.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 08-10-2014
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The activity of 11?-hydroxysteroid dehydrogenases (11?-HSD) is traditionally assessed using the ratio of cortisol to cortisone in urine or saliva. However, these biomarkers only reflect the local activity of 11?-HSD, and are easily affected by circadian variation of cortisol secretion. The shortcomings might be overcome by hair analysis. The present study aimed to develop an enhanced assay for simultaneous measurements of cortisol and cortisone in both hair and urine samples. The samples were collected from 29 patients under methadone maintenance treatment. The cortisol and cortisone were extracted either by solid phase extraction from a 20-mg milled hair sample after a 14-h incubation in 1ml of methanol, or by twice liquid-liquid extraction from a 20-fold diluted urine sample. The analyses were performed using high performance liquid chromatography tandem mass spectrometry with electrospray ionization in negative mode. Limits of detection and quantification were 0.5 and 1.25pg/mg for hair steroids and 0.2 and 0.5ng/ml for urinary steroids, respectively. The recoveries were more than 97%. The intra- and inter-day coefficients of variation were less than 10%. The ratios of cortisol to cortisone in hair and urine were both less than one, but did not correlate with each other. A possible reason for the lack of correlation was that the ratios in hair and urine might mostly reflect the activity of 11?-HSD type 2 in the eccrine sweat gland and in the kidney, respectively. Additionally, a significant correlation was observed between results obtained using external standard quantification and internal standard quantification.
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A long noncoding RNA protects the heart from pathological hypertrophy.
Nature
PUBLISHED: 08-10-2014
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The role of long noncoding RNA (lncRNA) in adult hearts is unknown; also unclear is how lncRNA modulates nucleosome remodelling. An estimated 70% of mouse genes undergo antisense transcription, including myosin heavy chain 7 (Myh7), which encodes molecular motor proteins for heart contraction. Here we identify a cluster of lncRNA transcripts from Myh7 loci and demonstrate a new lncRNA-chromatin mechanism for heart failure. In mice, these transcripts, which we named myosin heavy-chain-associated RNA transcripts (Myheart, or Mhrt), are cardiac-specific and abundant in adult hearts. Pathological stress activates the Brg1-Hdac-Parp chromatin repressor complex to inhibit Mhrt transcription in the heart. Such stress-induced Mhrt repression is essential for cardiomyopathy to develop: restoring Mhrt to the pre-stress level protects the heart from hypertrophy and failure. Mhrt antagonizes the function of Brg1, a chromatin-remodelling factor that is activated by stress to trigger aberrant gene expression and cardiac myopathy. Mhrt prevents Brg1 from recognizing its genomic DNA targets, thus inhibiting chromatin targeting and gene regulation by Brg1. It does so by binding to the helicase domain of Brg1, a domain that is crucial for tethering Brg1 to chromatinized DNA targets. Brg1 helicase has dual nucleic-acid-binding specificities: it is capable of binding lncRNA (Mhrt) and chromatinized--but not naked--DNA. This dual-binding feature of helicase enables a competitive inhibition mechanism by which Mhrt sequesters Brg1 from its genomic DNA targets to prevent chromatin remodelling. A Mhrt-Brg1 feedback circuit is thus crucial for heart function. Human MHRT also originates from MYH7 loci and is repressed in various types of myopathic hearts, suggesting a conserved lncRNA mechanism in human cardiomyopathy. Our studies identify a cardioprotective lncRNA, define a new targeting mechanism for ATP-dependent chromatin-remodelling factors, and establish a new paradigm for lncRNA-chromatin interaction.
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Study on decaying characteristics of activated sludge from a circular plug-flow reactor using response surface methodology.
Bioresour. Technol.
PUBLISHED: 08-09-2014
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Using pH values, temperature, and dissolved oxygen as the influencing factors, a decaying characteristics experiment of activated sludge was carried out by combining the LIVE/DEAD® Baclight technique with the 2,3,5-triphenyl tetrazolium chloride - dehydrogenase activity determination method. Using batch experiments, a response surface methodology was applied in the experimental design to determine the most important influential factor in the decay of activated sludge. The activated sludge mixed liquor for the experiment was generated in a laboratory-scale circular plug-flow reactor, which has already been approved for an invention patent. The analyzed results revealed that the most important influential factor in sludge activity decay is the pH, followed by temperature and then dissolved oxygen. After the decay experiment, 40.94-90.03% of sludge activity decay is caused by reduced cell activity, and the rest is due to cell death.
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Changes of Corneal Higher-Order Aberrations after Cataract Surgery.
Optom Vis Sci
PUBLISHED: 08-07-2014
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To demonstrate the time-dependent changes in corneal aberrations after cataract surgery and to analyze the effects of incision location on corneal aberrations.
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Preparation and Evaluation of Human-Murine Chimeric Antibody against Protective Antigen of Bacillus anthracis.
Int J Mol Sci
PUBLISHED: 08-06-2014
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The aim of this research is to develop a human/murine chimeric Fab antibody which neutralizes the anthrax toxin, protective antigen (PA). The chimeric Fab was constructed using variable regions of murine anti-PA monoclonal antibody in combination with constant regions of human IgG. The chimeric PA6-Fab was expressed in E. coli. BL21 and evaluated by ELISA and co-immunoprecipitation- mass spectra. The potency of PA6-Fab to neutralize LeTx was examined in J774A.1 cell viability in vitro and in Fisher 344 rats in vivo. The PA6-Fab did not have domain similarity corresponding to the current anti PA mAbs, but specifically bound to anthrax PA at an affinity of 1.76 nM, and was able to neutralize LeTx in vitro and protected 56.9% cells at 20 ?g/mL against anthrax LeTx. One hundred ?g PA6-Fab could neutralize 300 ?g LeTx in vivo. The PA6-Fab has potential as a therapeutic mAb for treatment of anthrax.
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Association between ubiquitin carboxy-terminal hydrolase-L1 S18Y variant and risk of Parkinson's disease: the impact of ethnicity and onset age.
Neurol. Sci.
PUBLISHED: 07-23-2014
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The Ubiquitin carboxy-terminal hydrolase-L1 (UCHL1) is a candidate risk gene for Parkinson' disease (PD), and a function SNP (rs5030732) in the coding region of this gene has been studied for the association with the disease extensively among worldwide populations, but the results were inconsistent and controversial. Here, to estimate the association between UCHL1 S18Y polymorphism and risk of PD in general population, we conducted a systematic meta-analysis by combining all available case-control subjects in Asian, European, and American populations, with a total of 7742 PD cases and 8850 healthy controls, and the pooled odds ratios (ORs) and 95 % confidence intervals (95 % CIs) for UCHL1 S18Y polymorphism and PD were calculated using the Mantel-Haenszel method with a fixed- or random-effects model. Subgroup analysis was also performed in different onset age-matched groups. Among high-quality studies, UCHL1 S18Y polymorphism was moderately associated with the risk of PD (allele contrasts, OR = 1.063, 95 % CI 1.008-1.122; p = 0.024; regressive genetic model, OR = 1.078, 95 % CI 1.005-1.157; p = 0.035). When stratifying for ethnicity, none association were observed in subgroups. Analysis of early-onset PD (EOPD) and late-onset PD (LOPD) revealed that the polymorphism was not associated with the risk of PD. In conclusion, our meta-analysis suggests that UCHL1 S18Y polymorphism is moderately associated with susceptibility to PD, and more studies are needed to confirm our conclusion.
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GLP-1 analog liraglutide enhances proinsulin processing in pancreatic ?-cells via a PKA-dependent pathway.
Endocrinology
PUBLISHED: 07-22-2014
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Hyperproinsulinemia has gained increasing attention in the development of type 2 diabetes. Clinical studies have demonstrated that glucagon-like peptide-1 (GLP-1)-based therapies significantly decrease plasma proinsulin/insulin ratio in patients with type 2 diabetes. However, the underlying mechanism remains unclear. Prohormone convertase (PC)-1/3 and PC2 are primarily responsible for processing proinsulin to insulin in pancreatic ?-cells. We have recently reported that Pax6 mutation down-regulated PC1/3 and PC2 expression, resulting in defective proinsulin processing in Pax6 heterozygous mutant (Pax6(m/+)) mice. In this study, we investigated whether and how liraglutide, a novel GLP-1 analog, modulated proinsulin processing. Our results showed that liraglutide significantly up-regulated PC1/3 expression and decreased the proinsulin to insulin ratio in both Pax6(m/+) and db/db diabetic mice. In the cultured mouse pancreatic ?-cell line, Min6, liraglutide stimulated PC1/3 and PC2 expression and lowered the proinsulin to insulin ratio in a dose- and time-dependent manner. Moreover, the beneficial effects of liraglutide on PC1/3 and PC2 expression and proinsulin processing were dependent on the GLP-1 receptor-mediated cAMP/protein kinase A signaling pathway. The same mechanism was recapitulated in isolated mouse islets. In conclusion, liraglutide enhanced PC1/3- and PC2-dependent proinsulin processing in pancreatic ?-cells through the activation of the GLP-1 receptor/cAMP/protein kinase A signaling pathway. Our study provides a new mechanism for improvement of pancreatic ?-cell function by the GLP-1-based therapy.
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A highly selective water-soluble optical probe for endogenous peroxynitrite.
Chem. Commun. (Camb.)
PUBLISHED: 07-19-2014
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A colorimetric and fluorescent probe C-Py-1 for ONOO(-) was prepared and it could exhibit high sensitivity and excellent selectivity toward ONOO(-) among reactive oxygen species (ROS) and reactive nitrogen species (RNS) with a rapid response time in 100% water solution. Meanwhile, C-Py-1 was successfully applied in the imaging of endogenous ONOO(-) in RAW264.7 cells.
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[Study on HIV viral load in plasma and drug resistance among AIDS patients receiving antiretroviral treatment in Dehong prefecture,Yunnan province].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 07-11-2014
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To understand HIV rival suppression and drug resistance (HIVDR) among AIDS patients who were receiving antiretroviral treatment (ART) in Dehong prefecture, Yunnan province.
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[Model design and stray light suppression technology of stray-light testing equipment for plane grating].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 07-11-2014
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Grating scatter is an important performance index for plane grating, and its measurement is a difficult problem for grating research field. In order to achieve stray-light of the instrument itself to be less than 10(-8) so that the grating scatter can be accurately measured, stray light in diffraction grating monochromators has been studied and an opto-mechanical model of measure instrument for plane grating is designed, which works in parallel light environment and based on the scalar diffraction theory and classical Fresnel-Kirchhoff diffraction theory. Main pathway of the instrumentation's stray light is calculated and analyzed by the simulation of stray-light testing equipment with ASAP software. Accordingly, four stray-light suppression structures including blocking rings, vanes, aperture stops and light traps are proposed to reduce instrument's scattered light and grating's multiple diffraction. Finally, contrast analysis of the instrumentation's stray light is made before and after adding stray-light suppression structures. Simulation and analysis results show that the max of instrument's stray light reduces from more than 10(-6) to less than 10(-8) after adding stray-light suppression structures and has met the stray-light testing equipment's design requirements whose goal is to realize accurate measurement greater than or equal to 10(-7) for grating scatter with grating's groove density changing from 300 to 3 600 gr x mm(-1). The research methods and results above will provide a theoretical basis for the research and development of the stray-light testing equipment for plane grating.
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Series of solvent-induced single-crystal to single-crystal transformations with different sizes of solvent molecules.
Inorg Chem
PUBLISHED: 07-01-2014
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A highly stable soft porous coordination polymer (PCP), namely [Cu3(TP)4(N3)2(DMF)2]·2H2O·2DMF (1), has been synthesized via an in situ synthesis of 4-tetrazole pyridine (TP) under solvothermal conditions (DMF = N,N'-dimethylformamide). Remarkably, the solvent molecules in 1 can be respectively exchanged with cyclohexane (C6H12), cyclopentane (C5H10), decahydronaphthalene (C10H18), 1,4-dioxane (C4H8O2), and tetrahydropyrane (C5H10O) in single-crystal to single-crystal (SCSC) manners to yield [Cu3(TP)4(N3)2(DMF)2]·3C6H12 (1a), [Cu3(TP)4(N3)2(DMF)2]·2C5H10 (1b), [Cu3(TP)4(N3)2(DMF)2]·H2O·C10H18 (1c), [Cu3(TP)4(N3)2(DMF)2]·C4H8O2 (1d), [Cu3(TP)4(N3)2]·3C4H8O2 (1e), and [Cu3(TP)4(N3)2]·2H2O·C5H10O (1f). Further, the occluded cyclohexane molecules in 1a can be removed by heating to give its porous guest-free form [Cu3(TP)4(N3)2(DMF)2] (1g). Particularly, in water, 1 can lose its coordinated N3(-) anions to generate [Cu(TP)2(H2O)4]·4H2O (1h). More interestingly, the soft PCP (1) demonstrates the guest selectivity for the cycloalkane solvents, namely cyclohexane, cyclopentane, and decahydronaphthalene, in SCSC manners for the first time, attributed to the synergy effect between the size and geometry of the solvent and the shape of the framework cavity. Moreover, the desolvated samples of 1e show the highly selective gas adsorption of CO2 over N2, indicating its potential application in the separation of the CO2/N2 mixture.
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Integrated transcriptomic and proteomic analysis of the bile stress response in a centenarian-originated probiotic Bifidobacterium longum BBMN68.
Mol. Cell Proteomics
PUBLISHED: 06-25-2014
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Bifidobacteria are natural inhabitants of the human gastrointestinal tract and well known for their health-promoting effects. Tolerance to bile stress is crucial for bifidobacteria to survive in the colon and to exert their beneficial actions. In this work, RNA-Seq transcriptomic analysis complemented with proteomic analysis was used to investigate the cellular response to bile in Bifidobacterium longum BBMN68. The transcript levels of 236 genes were significantly changed (? threefold, p < 0.001) and 44 proteins were differentially abundant (?1.6-fold, p < 0.01) in B. longum BBMN68 when exposed to 0.75 g l(-1) ox-bile. The hemolysin-like protein and bile efflux systems were significantly over produced, which might prevent bile adsorption and exclude bile, respectively. The cell membrane composition was modified probably by an increase of cyclopropane fatty acid and a decrease of transmembrane proteins, resulting in a cell membrane more impermeable to bile salts. Our hypothesis was later confirmed by surface hydrophobicity assay. The transcription of genes related to xylose utilization and bifid shunt were up-regulated, which increased the production of ATP and reducing equivalents to cope with bile-induced damages in a xylan-rich colon environment. Bile salts signal the B. longum BBMN68 to gut entrance and enhance the expression of esterase and sortase associated with adhesion and colonization in intestinal tract, which was supported by a fivefold increased adhesion ability to HT-29 cells by BBMN68 upon bile exposure. Notably, bacterial one-hybrid and EMSA assay revealed that the two-component system senX3-regX3 controlled the expression of pstS in bifidobacteria and the role of this target gene in bile resistance was further verified by heterologous expression in Lactococcus lactis. Taken altogether, this study established a model for global response mechanisms in B. longum to bile.
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Hybridizing triboelectrification and electromagnetic induction effects for high-efficient mechanical energy harvesting.
ACS Nano
PUBLISHED: 06-16-2014
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The recently introduced triboelectric nanogenerator (TENG) and the traditional electromagnetic induction generator (EMIG) are coherently integrated in one structure for energy harvesting and vibration sensing/isolation. The suspended structure is based on two oppositely oriented magnets that are enclosed by hollow cubes surrounded with coils, which oscillates in response to external disturbance and harvests mechanical energy simultaneously from triboelectrification and electromagnetic induction. It extends the previous definition of hybrid cell to harvest the same type of energy with multiple approaches. Both the sliding-mode TENG and contact-mode TENG can be achieved in the same structure. In order to make the TENG and EMIG work together, transformers are used to match the output impedance between these two power sources with very different characteristics. The maximum output power of 7.7 and 1.9 mW on the same load of 5 k? was obtained for the TENG and EMIG, respectively, after impedance matching. Benefiting from the rational design, the output signal from the TENG and the EMIG are in phase. They can be added up directly to get an output voltage of 4.6 V and an output current of 2.2 mA in parallel connection. A power management circuit was connected to the hybrid cell, and a regulated voltage of 3.3 V with constant current was achieved. For the first time, a logic operation was carried out on a half-adder circuit by using the hybrid cell working as both the power source and the input digit signals. We also demonstrated that the hybrid cell can serve as a vibration isolator. Further applications as vibration dampers, triggers, and sensors are all promising.
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Clinical experience of surgical intervention for severe acute pancreatitis.
Chin. Med. J.
PUBLISHED: 06-04-2014
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The controversy on the treatment strategy for severe acute pancreatitis (SAP) has never stopped for the past century. Even now surgical procedures play a decisive role in the treatment of SAP, especially in managing the related complications, but the rational indications, timing, and approaches of surgical intervention for SAP are still inconclusive.
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Mitochondria-targeted colorimetric and fluorescent probes for hypochlorite and their applications for in vivo imaging.
Chem. Commun. (Camb.)
PUBLISHED: 05-29-2014
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Two mitochondria-targeted real-time probes were presented, which could selectively respond to hypochlorite over other ROS. Meanwhile, the "off-on" probes could be successfully applied in the in vivo imaging of hypochlorite in living mice.
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Respiratory syncytial virus infection modulates interleukin?8 production in respiratory epithelial cells through a transcription factor?activator protein?1 signaling pathway.
Mol Med Rep
PUBLISHED: 05-28-2014
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Respiratory syncytial virus (RSV) is a leading cause of respiratory duct infection that can result in severe clinical symptoms, particularly among children under 3 years of age. In the current study, the effect of RSV on airway epithelial cell function and the potential signaling pathways involved were investigated. A549 human airway epithelial cells were infected with RSV at a multiplicity of infection of 1. After 24 h, interleukin (IL)?8 secretion in the cell supernatant was analyzed. A microarray assay of RSV?infected A549 cells was conducted in order to identify any potential pathways involved, and quantitative polymerase chain reaction was performed to examine mRNA expression levels in these pathways. Electrophoretic mobility shift assays of nuclear transcription factors were conducted for further verification. IL?8 levels increased significantly in the supernatant of RSV?infected A549 cells compared with levels in non?infected cells. Microarray data suggested the involvement of the Toll?like receptor 4 (TLR4) pathway, and mRNA expression levels of genes (MYD88, TRAM and TRIF) involved in this pathway were higher in infected cells. Enhanced synthesis of activator protein?1 (AP?1) was observed. RSV infection of A549 cells may promote IL?8 secretion. In conclusion, the results of the present study indicate that the TLR4 signaling pathway, in conjunction with MYD88, TRAM, TRIF and the transcription factor AP?1, may activate immune responses to RSV infection in airway epithelial cells.
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High-fat diet induces early-onset diabetes in heterozygous Pax6 mutant mice.
Diabetes Metab. Res. Rev.
PUBLISHED: 05-13-2014
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Type 2 diabetes is caused by interactions between genetic and environmental factors. Our previous studies reported that paired box?6 mutation heterozygosity (Pax6(m/+)) led to defective proinsulin processing and subsequent abnormal glucose metabolism in mice at 6 ?months of age. However, high-fat diet exposure could be an important incentive for diabetes development. In this study, we aimed to develop a novel diabetic model imitating human type 2 diabetes by exposing Pax6(m/+) mice to high-fat diet and to explore the underlying mechanism of diabetes in this model.
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Triboelectrification based motion sensor for human-machine interfacing.
ACS Appl Mater Interfaces
PUBLISHED: 05-12-2014
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We present triboelectrification based, flexible, reusable, and skin-friendly dry biopotential electrode arrays as motion sensors for tracking muscle motion and human-machine interfacing (HMI). The independently addressable, self-powered sensor arrays have been utilized to record the electric output signals as a mapping figure to accurately identify the degrees of freedom as well as directions and magnitude of muscle motions. A fast Fourier transform (FFT) technique was employed to analyse the frequency spectra of the obtained electric signals and thus to determine the motion angular velocities. Moreover, the motion sensor arrays produced a short-circuit current density up to 10.71 mA/m(2), and an open-circuit voltage as high as 42.6 V with a remarkable signal-to-noise ratio up to 1000, which enables the devices as sensors to accurately record and transform the motions of the human joints, such as elbow, knee, heel, and even fingers, and thus renders it a superior and unique invention in the field of HMI.
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Relationship between urinary nickel and methylation of p15, p16 in workers exposed to nickel.
J. Occup. Environ. Med.
PUBLISHED: 05-09-2014
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The purpose of this study was to investigate the relationship between urinary nickel and methylation of p15, p16 in workers exposed to nickel.
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Activation of glucagon-like peptide-1 receptor inhibits growth and promotes apoptosis of human pancreatic cancer cells in a cAMP-dependent manner.
Am. J. Physiol. Endocrinol. Metab.
PUBLISHED: 05-06-2014
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Glucagon-like peptide-1 (GLP-1) promotes pancreatic ?-cell regeneration through GLP-1 receptor (GLP-1R) activation. However, whether it promotes exocrine pancreas growth and thereby increases the risk of pancreatic cancer has been a topic of debate in recent years. Clinical data and animal studies published so far have been controversial. In the present study, we report that GLP-1R activation with liraglutide inhibited growth and promoted apoptosis in human pancreatic cancer cell lines in vitro and attenuated pancreatic tumor growth in a mouse xenograft model in vivo. These effects of liraglutide were mediated through activation of cAMP production and consequent inhibition of Akt and ERK1/2 signaling pathways in a GLP-1R-dependent manner. Moreover, we examined GLP-1R expression in human pancreatic cancer tissues and found that 43.3% of tumor tissues were GLP-1R-null. In the GLP-1R-positive tumor tissues (56.7%), the level of GLP-1R was lower compared with that in tumor-adjacent normal pancreatic tissues. Furthermore, the GLP-1R-positive tumors were significantly smaller than the GLP-1R-null tumors. Our study shows for the first time that GLP-1R activation has a cytoreductive effect on human pancreatic cancer cells in vitro and in vivo, which may help address safety concerns of GLP-1-based therapies in the context of human pancreatic cancer.
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[Video endoscopic inguinal lymphadenectomy via hypogastric/limb subcutaneous approach for early-stage vulvar cancer].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 04-12-2014
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To describe and compare video endoscopic inguinal lymphadenectomy via hypogastric and limb approach (VEIL-H vs VEIL-L) in patients with invasive vulvar cancer.
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Intracellular Na(+) overload causes oxidation of CaMKII and leads to Ca(2+) mishandling in isolated ventricular myocytes.
J. Mol. Cell. Cardiol.
PUBLISHED: 03-24-2014
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An increase of late Na(+) current (INaL) in cardiac myocytes can raise the cytosolic Na(+) concentration and is associated with activation of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and alterations of mitochondrial metabolism and Ca(2+) handling by sarcoplasmic reticulum (SR). We tested the hypothesis that augmentation of INaL can increase mitochondrial reactive oxygen species (ROS) production and oxidation of CaMKII, resulting in spontaneous SR Ca(2+) release and increased diastolic Ca(2+) in myocytes. Increases of INaL and/or of the cytosolic Na(+) concentration led to mitochondrial ROS production and oxidation of CaMKII to cause dysregulation of Ca(2+) handling in rabbit cardiac myocytes.
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Endovascular treatment for symptomatic iliac vein compression syndrome: a prospective consecutive series of 48 patients.
Ann Vasc Surg
PUBLISHED: 02-25-2014
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We sought to assess the prevalence of iliac vein compression syndrome (IVCS) in patients with unilateral left lower limb chronic venous disease and evaluate the feasibility and effectiveness of endovascular treatment for IVCS.
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Post-translational modifications of proliferating cell nuclear antigen: A key signal integrator for DNA damage response (Review).
Oncol Lett
PUBLISHED: 02-13-2014
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Previous studies have shown that the post-translational modifications of proliferating cell nuclear antigen (PCNA) may be crucial in influencing the cellular choice between different pathways, such as the cell cycle checkpoint, DNA repair or apoptosis pathways, in order to maintain genomic stability. DNA damage leads to replication stress and the subsequent induction of PCNA modification by small ubiquitin (Ub)-related modifiers and Ub, which has been identified to affect multiple biological processes of genomic DNA. Thus far, much has been learned concerning the behavior of modified PCNA as a key signal integrator in response to DNA damage. In humans and yeast, modified PCNA activates DNA damage bypass via an error-prone or error-free pathway to prevent the breakage of DNA replication forks, which may potentially induce double-strand breaks and subsequent chromosomal rearrangements. However, the exact mechanisms by which these pathways work and by what means the modified PCNA is involved in these processes remain elusive. Thus, the improved understanding of PCNA modification and its implications for DNA damage response may provide us with more insight into the mechanisms by which human cells regulate aberrant recombination events, and cancer initiation and development. The present review focuses on the post-translational modifications of PCNA and its important functions in mediating mammalian cellular response to different types of DNA damage.
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Recombinant tissue plasminogen activator for hemodynamically stable patients experiencing an acute pulmonary embolism: a meta-analysis.
Thromb. Res.
PUBLISHED: 01-22-2014
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The role of thrombolytic therapy for the initial treatment of hemodynamically stable patients experiencing an acute pulmonary embolism remains controversial.
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Determination of BmKCT-13, a chlorotoxin-like peptide, in rat plasma by LC-MS/MS: application to a preclinical pharmacokinetic study.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-14-2014
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A novel chlorotoxin-like toxin derived from Buthus martensii Karsch, namely BmKCT-13, is a potential candidate for glioma therapy and highly homologous to the chlorotoxin (CTX) derived from the venom of the scorpion Leiurus quinquestriatus. In this study, a simple, sensitive, and robust analytical method based on liquid chromatography-tandem mass spectrometry has been developed for the determination of BmKCT-13 in rat plasma using CTX as internal standard (IS). After sample preparation by protein precipitation with 0.1% formic acid in methanol, chromatography was performed on a Hanbon Dubhe C18 column (150 mm × 2.1 mm, 5 ?m, and 100 Å) using a gradient elution with 0.1% formic acid in water and methanol. Mass spectrometry involved positive electrospray ionization and multiple reaction monitoring of the transitions at m/z 780.2?69.9 for BmKCT-13 and m/z 800.2?69.7 for CTX. The method was linear over the concentration range 10-1000 ng/mL with a lower limit of quantification of 10 ng/mL. Intra- and inter-day precision (expressed as relative standard deviation, RSD) were ?8.1 and ?7.9%, respectively, with intra-and inter-day accuracy of 94.5-99.0%. Recoveries of BmKCT-13 and IS were more than 65% and matrix effects were not significant. Stability studies showed that BmKCT-13 was stable under a variety of storage conditions. The method was successfully applied to a pharmacokinetic study involving intravenous administration of BmKCT-13 to rats.
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Clinicopathologic characteristics of prefibrotic-early primary myelofibrosis in Chinese patients.
Hum. Pathol.
PUBLISHED: 01-11-2014
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The clinicopathologic features of patients with prefibrotic-early primary myelofibrosis (PEPMF) are still uncertain, and the characteristics of PEPMF in Asian patients are rarely reported. This study analyzed the clinicopathologic characteristics of 42 Chinese patients with PMF newly diagnosed according to the 2008 World Health Organization criteria. Some clinical and laboratory features of the patients differed significantly from those of the predominantly white patients in Western countries. Chinese patients with PEPMF were more often male (1.28:1) and younger, less likely to have higher median hemoglobin concentrations (126 g/L), less frequently had palpable spleens (35.7%), and had longer median times between prefibrotic-early and classical PEPMF (64 months). On bone marrow trephine sections, Chinese patients were more likely to have increased granulopoiesis (78.6%) and less frequently had balloon-like megakaryocytes (61.9%), giant and staghorn megakaryocytes (35.7%), or megakaryocytes with hyperchromatic and dysplastic nuclei (40.4%). In conclusion, some clinicopathologic characteristics of PEPMF in Chinese patients in China differ substantially from those seen in predominantly white patients in Western countries, and more clinicopathologic studies involving different ethnic populations and geographic regions of the world should help unfold the characteristics of this disease.
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Identification of potential serum proteomic biomarkers for clear cell renal cell carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
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To investigate discriminating protein patterns and serum biomarkers between clear cell renal cell carcinoma (ccRCC) patients and healthy controls, as well as between paired pre- and post-operative ccRCC patients.
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Crossover effects of estrogen receptor status on breast cancer-specific hazard rates by age and race.
PLoS ONE
PUBLISHED: 01-01-2014
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Previous studies found that the risk of breast cancer-related death is greater in estrogen receptor (ER)-negative disease than in ER-positive disease within 5 years of diagnosis, but greater for ER-positive disease than for ER-negative disease more than 5 years after diagnosis. This phenomenon is referred to as ER-positive and -negative crossover. Our aim was to evaluate this crossover by determining the timing of the hazard of breast cancer death by patient, clinical, and tumor factors.
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An optimized triple modality reporter for quantitative in vivo tumor imaging and therapy evaluation.
PLoS ONE
PUBLISHED: 01-01-2014
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We present an optimized triple modality reporter construct combining a far-red fluorescent protein (E2-Crimson), enhanced firefly luciferase enzyme (Luc2), and truncated wild type herpes simplex virus I thymidine kinase (wttk) that allows for sensitive, long-term tracking of tumor growth in vivo by fluorescence, bioluminescence, and positron emission tomography. Two human cancer cell lines (MDA-MB-231 breast cancer and HT-1080 fibrosarcoma cancer) were successfully transduced to express this triple modality reporter. Fluorescence and bioluminescence imaging of the triple modality reporter were used to accurately quantify the therapeutic responses of MDA-MB-231 tumors to the chemotherapeutic agent monomethyl auristatin E in vivo in athymic nude mice. Positive correlation was observed between the fluorescence and bioluminescence signals, and these signals were also positively correlated with the ex vivo tumor weights. This is the first reported use of both fluorescence and bioluminescence signals from a multi-modality reporter construct to measure drug efficacy in vivo.
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Transport of Oxidized Multi-Walled Carbon Nanotubes through Silica Based Porous Media: Influences of Aquatic Chemistry, Surface Chemistry, and Natural Organic Matter.
Environ. Sci. Technol.
PUBLISHED: 12-04-2013
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This paper provides results from studies of the transport of oxidized multi-walled carbon nanotubes (O-MWCNTs) of varying surface oxygen concentrations under a range of aquatic conditions and through uniform silica glass bead media. In the presence of Na(+), the required ionic strength (IS) for maximum particle attachment efficiency (i.e., the critical deposition concentration, or CDC) increased as the surface oxygen concentration of the O-MWCNTs or pH increased, following qualitative tenets of theories based on electrostatic interactions. In the presence of Ca(2+), CDC values were lower than those with Na(+) present, but were no longer sensitive to surface oxygen content, suggesting that Ca(2+) impacts the interactions between O-MWCNTs and glass beads by mechanisms other than electrostatic alone. The presence of Suwannee River natural organic matter (SRNOM) decreased the attachment efficiency of O-MWCNTs in the presence of either Na(+) or Ca(2+), but with more pronounced effects when Na(+) was present. Nevertheless, low concentrations of SRNOM (<4 mg/L of dissolved organic carbon) were sufficient to mobilize all O-MWCNTs studied at CaCl2 concentrations as high as 10 mM. Overall, this study reveals that NOM content, pH, and cation type show more importance than surface chemistry in affecting O-MWCNTs deposition during transport through silica-based porous media.
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Changes in pharmacokinetic profiles of acetaminophen and its glucuronide after pretreatment with combinations of N-acetylcysteine and either glycyrrhizin, silibinin or spironolactone in rat.
Xenobiotica
PUBLISHED: 11-19-2013
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Abstract 1. The present study was to investigate the effects of giving N-acetylcysteine (NAC) alone and in combination with either glycyrrhizin (GL), silibinin (SIB) or spironolactone (SL) on the plasma pharmacokinetic (PK) profiles, hepatic exposure, biliary excretion and urinary excretion of acetaminophen (APAP) and its major metabolite, acetaminophen glucuronide (AG). 2. Groups of rats (n?=?5) were pretreated with oral doses of either NAC, NAC?+?GL, NAC?+?SIB or NAC?+?SL on five occasions every 12?h. At 1?h, after the last dose, they received APAP (200?mg/kg) by intraperitoneal injection. Blood, bile, liver and urine samples were collected at various times after APAP injection and analyzed for APAP and AG by HPLC. NAC alone and NAC?+?SIB did not significantly change the PK profiles of APAP and AG. In contrast, NAC?+?GL decreased the biliary excretion of APAP and AG leading to accumulation of APAP in the liver and systemic circulation whereas NAC?+?SL [multidrug resistance associated 2 (Mrp2) inducer] increased the biliary excretion of AG and decreased the hepatic exposure to APAP and AG. 3. Our results suggest that Mrp2 inhibitor GL should be discouraged with NAC to treat APAP hepatotoxicity. Such PK drug-drug interactions should be considered in the treatment of APAP-induced liver injury.
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Hydrothermally formed functional niobium oxide doped tungsten nanorods.
Nanotechnology
PUBLISHED: 11-14-2013
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Nanorod forms of metal oxides are recognized as one of the most remarkable morphologies. Their structure and functionality have driven important advancements in a vast range of electronic devices and applications. In this work, we postulate a novel concept to explain how numerous localized surface states can be engineered into the bandgap of niobium oxide nanorods using tungsten. We discuss their contributions as local state surface charges for the modulation of a Schottky barrier height, the relative dielectric constant and their respective conduction mechanisms. Their effects on hydrogen gas molecule interaction mechanisms are also examined herein. We synthesized niobium tungsten oxide (Nb17W2O25) nanorods via a hydrothermal growth method and evaluated the Schottky barrier height, ideality factor, dielectric constant and trap energy level from the measured I-V versus temperature characteristics in the presence of air and hydrogen to show the validity of our postulations.
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Harvesting energy from the natural vibration of human walking.
ACS Nano
PUBLISHED: 11-06-2013
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The triboelectric nanogenerator (TENG), a unique technology for harvesting ambient mechanical energy based on the triboelectric effect, has been proven to be a cost-effective, simple, and robust approach for self-powered systems. However, a general challenge is that the output current is usually low. Here, we demonstrated a rationally designed TENG with integrated rhombic gridding, which greatly improved the total current output owing to the structurally multiplied unit cells connected in parallel. With the hybridization of both the contact-separation mode and sliding electrification mode among nanowire arrays and nanopores fabricated onto the surfaces of two contact plates, the newly designed TENG produces an open-circuit voltage up to 428 V, and a short-circuit current of 1.395 mA with the peak power density of 30.7 W/m(2). Relying on the TENG, a self-powered backpack was developed with a vibration-to-electric energy conversion efficiency up to 10.62(±1.19) %. And it was also demonstrated as a direct power source for instantaneously lighting 40 commercial light-emitting diodes by harvesting the vibration energy from natural human walking. The newly designed TENG can be a mobile power source for field engineers, explorers, and disaster-relief workers.
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Triboelectric Nanogenerator Built on Suspended 3D Spiral Structure as Vibration and Positioning Sensor and Wave Energy Harvester.
ACS Nano
PUBLISHED: 10-31-2013
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An unstable mechanical structure that can self-balance when perturbed is a superior choice for vibration energy harvesting and vibration detection. In this work, a suspended 3D spiral structure is integrated with a triboelectric nanogenerator (TENG) for energy harvesting and sensor applications. The newly designed vertical contact-separation mode TENG has a wide working bandwidth of 30 Hz in low-frequency range with a maximum output power density of 2.76 W/m(2) on a load of 6 M?. The position of an in-plane vibration source was identified by placing TENGs at multiple positions as multichannel, self-powered active sensors, and the location of the vibration source was determined with an error less than 6%. The magnitude of the vibration is also measured by the output voltage and current signal of the TENG. By integrating the TENG inside a buoy ball, wave energy harvesting at water surface has been demonstrated and used for lighting illumination light, which shows great potential applications in marine science and environmental/infrastructure monitoring.
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[Study on the role of western blot band profile for the detection of recent HIV infection].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 10-08-2013
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To obtain information on HIV disease progression through western blot (WB) band profile.
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Quantitative determination of ?-N-carboxymethyl-l-lysine in human plasma by liquid chromatography-tandem mass spectrometry.
J Pharm Biomed Anal
PUBLISHED: 09-24-2013
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?-N-carboxymethyl-l-lysine (CML) is a stable chemical modification of protein lysine residues resulting from glycation and oxidation reactions and a potential biomarker of oxidative stress caused by sugar and lipid oxidation. In this study, a rapid, simple and sensitive method based on liquid chromatography-tandem spectrometry (LC-MS/MS) for the determination of CML in human plasma has been developed and validated. Sample preparation involved protein precipitation using trichloroacetic acid after addition of deuterated CML as internal standard. Chromatography was performed on an amino column by gradient-elution with a mobile phase containing acetonitrile:ultrapure water (80:20, v/v). CML and CML-d2 were detected by multiple reaction monitoring mode with ion pairs 205.0/130.1 and 207.2/84.1 respectively. The assay was linear in the range 10-1000ng/mL with a lower limit of quantitation (LLOQ) of 10ng/mL and recovery >90%. Assay validation showed that inter- and intra-day precision and accuracy were satisfactory. The method was applied to compare plasma CML levels in healthy Chinese subjects and patients with diabetes and uremia. In healthy subjects CML concentration (mean±SD) was 16.6±7.8ng/mL. CML level in diabetic patients was not significantly different from healthy subjects whereas the level in patients with uremia was significantly higher than both healthy subjects and diabetic patients (P<0.001). The method will be useful to assess the value of CML as a biomarker of diabetic vascular complications resulting from elevated oxidative stress.
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Evaluation of reported prostate cancer risk-associated SNPs from genome-wide association studies of various racial populations in Chinese men.
Prostate
PUBLISHED: 09-09-2013
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Several genome-wide association studies (GWAS) of prostate cancer (PCa) have identified many single nucleotide polymorphisms (SNPs) that are significantly associated with PCa risk in various racial groups. The objective of this study is to evaluate which of these SNPs are associated with PCa risk in Chinese men and estimate their strength of association.
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Human skin based triboelectric nanogenerators for harvesting biomechanical energy and as self-powered active tactile sensor system.
ACS Nano
PUBLISHED: 09-05-2013
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We report human skin based triboelectric nanogenerators (TENG) that can either harvest biomechanical energy or be utilized as a self-powered tactile sensor system for touch pad technology. We constructed a TENG utilizing the contact/separation between an area of human skin and a polydimethylsiloxane (PDMS) film with a surface of micropyramid structures, which was attached to an ITO electrode that was grounded across a loading resistor. The fabricated TENG delivers an open-circuit voltage up to -1000 V, a short-circuit current density of 8 mA/m(2), and a power density of 500 mW/m(2) on a load of 100 M?, which can be used to directly drive tens of green light-emitting diodes. The working mechanism of the TENG is based on the charge transfer between the ITO electrode and ground via modulating the separation distance between the tribo-charged skin patch and PDMS film. Furthermore, the TENG has been used in designing an independently addressed matrix for tracking the location and pressure of human touch. The fabricated matrix has demonstrated its self-powered and high-resolution tactile sensing capabilities by recording the output voltage signals as a mapping figure, where the detection sensitivity of the pressure is about 0.29 ± 0.02 V/kPa and each pixel can have a size of 3 mm × 3 mm. The TENGs may have potential applications in human-machine interfacing, micro/nano-electromechanical systems, and touch pad technology.
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High-yield production of highly fluorinated graphene by direct heating fluorination of graphene-oxide.
ACS Appl Mater Interfaces
PUBLISHED: 08-23-2013
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By employing honeycomb GO with large surface area as the starting materials and using elemental fluorine, we developed a novel, straightforward topotactic route toward highly fluorinated graphene in really large quantities at low temperature. The value of F/C molar ratio approaches to 1.02. Few-layer fluorinated graphene sheets are obtained, among which the yield of monolayered FG sheet is about 10% and the number of layers is mainly in the range of 2-5. Variations in morphology and chemical structure of fluorinated graphene were explored, and some physical properties were reported.
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Epicardial calcineurin-NFAT signals through Smad2 to direct coronary smooth muscle cell and arterial wall development.
Cardiovasc. Res.
PUBLISHED: 08-14-2013
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Congenital coronary artery anomalies produce serious events that include syncope, arrhythmias, myocardial infarction, or sudden death. Studying the mechanism of coronary development will contribute to the understanding of the disease and help design new diagnostic or therapeutic strategies. Here, we characterized a new calcineurin-NFAT signalling which specifically functions in the epicardium to regulate the development of smooth muscle wall of the coronary arteries.
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Separation and enrichment of major quinolizidine type alkaloids from Sophora alopecuroides using macroporous resins.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 08-03-2013
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Matrine (MT), oxymatrine (OM) and sophoridine (SP) are three bioactive alkaloids in Sophora alopecuroides. In the present study, the chromatographic characteristics of six widely used macroporous resins, namely NKA, NKA-9, HPD-100, HPD-722, HPD-750, and AB-8, respectively, towards the separation and enrichment of the three alkaloids from the aqueous extract of S. alopecuroides are critically evaluated. The results indicated that AB-8 resin offered the best absorption and desorption capacity and its adsorption data fitted best to the Freundlich isotherm. Dynamic adsorption and desorption experiments on packed columns of AB-8 resin have been investigated for optimization of chromatographic parameters. The adsorption of the alkaloids on the resin was best achieved by 5 bed volume (BV) of sample solution of pH 10 with a flow rate of 2BV/h. The desorption of the compounds from the resin was effectively completed by using 5BV of 80% ethanol in water at a flow rate of 2BV/h. After one run of adsorption and desorption, the contents of MT, OM, and SP were increased from 9.30, 8.39 and 9.84% to 22.22, 21.44 and 28.02%, the recovery were 69.4, 78.3 and 72.6%, respectively. This method would provide useful information to the industrial production of the alkaloids from S. alopecuroides.
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Microemulsion-mediated solvothermal synthesis and photoluminescent properties of europium tungstate nanostructures.
J Nanosci Nanotechnol
PUBLISHED: 07-19-2013
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The controlled synthesis of Eu2(WO4)3 nanostructures with different morphologies, namely ellipsoidlike, rodlike, cubelike, rod-bundlelike, and mesoporous spindlike, has been successfully achieved by the cationic surfactant-CTAB (cetyltrimethylammoniumbromide)-microemulsion-mediated and anionic surfactant-SDS (sodium dodecyl sulfate)-microemulsion-mediated solvothermal method separately. Various comparison experiments showed that fundamental experimental parameters, such as the water content, reaction temperature and the type of surfactants played important roles in the morphological control of Eu2(WO4)3 nanostructures. The possible growth mechanisms of these nanocrystals were elucidated in detail.
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Ultrathin BaTiO3 nanowires with high aspect ratio: a simple one-step hydrothermal synthesis and their strong microwave absorption.
ACS Appl Mater Interfaces
PUBLISHED: 07-16-2013
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In this paper, we report the facile synthesis of ultrathin barium titanate (BaTiO3) nanowires with gram-level yield via a simple one-step hydrothermal treatment. Our BaTiO3 nanowires have unique features: single crystalline, uniform size distribution and ultra high aspect ratio. The synergistic effects including both Ostwald ripening and cation exchange reaction are responsible for the growth of the ultrathin BaTiO3 nanowires. The microwave absorption capability of the ultrathin BaTiO3 nanowires is improved compared to that of BaTiO3 nanotorus,1 with a maximum reflection loss as high as -24.6 dB at 9.04 GHz and an absorption bandwidth of 2.4 GHz (<-10 dB). Our method has some novel advantages: simple, facile, low cost and high synthesis yield, which might be developed to prepare other ferroelectric nanostructures. The strong microwave absorption property of the ultrathin BaTiO3 nanowires indicates that these nanowires could be used as promising materials for microwave-absorption and stealth camouflage techniques.
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Predictive value of the surface-enhanced resonance Raman scattering-based MTT assay: a rapid and ultrasensitive method for cell viability in situ.
Anal. Chem.
PUBLISHED: 07-15-2013
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SERRS (surface-enhanced resonance Raman scattering) has been used to develop and optimize a novel and quantitative MTT assay for living cell viability. This highly sensitive method derives from two factors for formazan signal enhancing: the addition of Au nanoparticles and the resonance effect by 632.8 nm of excitation. The results show that the background elements, such as excessive MTT residues, serum, and the drug, did not interfere with the detection of formazan. Moreover, the detection limit of formazan is as low as 1 ng/mL. With the use of this method to quantify metabolically viable cells, dose-response curves of treated and untreated cells with the drug were constructed on the human lung cancer cell A549. The results also show that the Raman signal generated is dependent on the degree of activation of the cells. In comparison to the traditional method, the main advantages of this method are its rapidity (30 min), high-selectivity, high-precision, and cost-effectiveness (0.1 mg/mL MTT) without time-consuming steps and any modifying or labeling procedure. This work reports on an improved research tool that may help researchers apply this method for in situ cell assays.
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[Role of ubiquitin ligase Ring2 in DNA damage induced by benzo[a]pyrene].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 06-28-2013
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To investigate the role of ubiquitin ligase Ring2 in the DNA damage induced by benzo[a]pyrene (B[a]P).
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In Vivo Efficacy of HD0471953: A Novel GPR119 Agonist for the Treatment of Type 2 Diabetes Mellitus.
J Diabetes Res
PUBLISHED: 06-25-2013
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G-protein coupled receptor 119 (GPR119) has emerged as a promising new target for the treatment of type 2 diabetes mellitus. The expression of GPR119 on the pancreatic B cells and intestinal L cells provides a unique opportunity for a single drug to promote insulin and GLP-1 secretion. In this study, we identified a novel small molecule GPR119 agonist, HD0471953, from our large library of synthetic compounds based on its ability to anti-hyperglycemic effects on T2DM murine models. We have tested the acute efficacy of HD0471953 by the oral glucose tolerance test (OGTT) with normal C57BL/6J mice. Then, chronic administrations of HD0471953 were performed to evaluate the efficacy on various diabetic rodent models. Single administration of HD0471953 showed improved glycemic control with a dose-dependent manner in OGTT with normal mice, and the insulin and GLP-1 were also increased. To identify chronic efficacy, we have observed a decline of blood glucose and fasting insulin in a dose-dependent manner of 10, 20, and 50?mpk in db/db mice. The results suggest that HD0471953 may be a potentially promising anti-hyperglycemic agent for the treatment of patients with type 2 diabetes mellitus.
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Characteristics of novel hair-based biomarker for the activity assessment of 11?-hydroxysteroid dehydrogenase.
Clin. Chim. Acta
PUBLISHED: 06-24-2013
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The ratio of hair cortisol to cortisone (R(hcc)) would be a potential biomarker to assess long-term activity of 11?-hydroxysteroid dehydrogenase (11?-HSD). Hair cortisol concentration in human varied with positions of hair segments in hair shaft, head locations of hair sampling and treatment methods of hair samples. However, currently unknown is whether these factors influence the determination of R(hcc) value.
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HspA1A facilitates DNA repair in human bronchial epithelial cells exposed to Benzo[a]pyrene and interacts with casein kinase 2.
Cell Stress Chaperones
PUBLISHED: 06-05-2013
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Benzo[a]pyrene (BaP) is a ubiquitously distributed environmental pollutant that induces deoxyribonucleic acid (DNA) damage. The inducible heat shock protein (HspA1A) can function as a molecular chaperone; however, its role in DNA repair remains largely unknown. In the present study, human bronchial epithelial cells (16HBE) stably transfected with plasmids carrying HspA1A gene or shRNAs against HspA1A were treated with BaP. DNA damage levels of the cells were evaluated by comet assay. Results suggest that HspA1A could protect cells against DNA damage and facilitate the decrease of DNA damage levels during the first 2 h of DNA repair. DNA repair capacity (DRC) of Benzo(a)pyrene diol epoxide (BPDE)-DNA adducts was evaluated by host cell reactivation assay in the stable 16HBE cells transfected with luciferase reporter vector PCMVluc pretreated with BPDE. Compared with control cells, cells overexpressing HspA1A showed higher DRC (p?
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Novel GPR119 agonist HD0471042 attenuated type 2 diabetes mellitus.
Arch. Pharm. Res.
PUBLISHED: 05-30-2013
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In type 2 diabetes mellitus (T2DM) patients, the gradual loss of pancreatic ?-cell function is a characteristic feature of disease progression that is associated with sustained hyperglycemia. Recently, G protein-coupled receptor 119 (GPR119) has been identified as a promising anti-diabetic therapeutic target. It is predominantly expressed in pancreatic ?-cells, directly promotes glucose stimulated insulin secretion and indirectly increases glucagon-like peptide 1 (GLP-1) levels reducing appetite and food intake. Activation of GPR119 leads to insulin release in ?-cells by increasing intracellular cAMP. Here, we identified a novel structural class of small-molecule GPR119 agonists, HD0471042, consisting of substituted a 3-isopropyl-1,2,4-oxadiazol-piperidine derivative with promising potential for the treatment of T2DM. The GPR119 agonist, HD0471042 increased intracellular cAMP levels in stably human GPR119 expressing CHO cell lines and HIT-T15 cell lines, hamster ?-cell line expressing endogenously GPR119. HD0471042, significantly elevated insulin release in INS-1 cells of rat pancreatic ?-cell line. In in vivo experiments, a single dose of HD0471042 improved glucose tolerance. Insulin and GLP-1 level were increased in a dose-dependent manner. Treatment with HD0471042 for 6 weeks in diet induced obesity mice and for 4 weeks in ob/ob and db/db mice improved glycemic control and also reduced weight gain in a dose-dependent manner. These data demonstrate that the novel GPR119 agonist, HD0471042, not only effectively controlled glucose levels, but also had an anti-obesity effect, a feature observed with GLP-1. We therefore suggest that HD0471042 represents a new type of anti-diabetes agent with anti-obesity potential for the effective treatment of type 2 diabetes.
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Differential microRNA expression in renal cell carcinoma.
Oncol Lett
PUBLISHED: 05-14-2013
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The present study aimed to detect microRNA expression levels in the tissues and sera of patients with clear cell renal cell carcinoma (ccRCC). The association of microRNA expression with ccRCC clinical pathology was analyzed, and the potential of the microRNAs as ccRCC serum markers and the significance of their expression in the clinical diagnosis, staging, prognosis and selection of new therapeutic targets for ccRCC were discussed. Specific microRNAs were selected according to the associated literature. TaqMan quantitative polymerase chain reaction (qPCR) technology was used to determine the expression levels of selected microRNAs. miR-34a, miR-224 and miR-21 were upregulated, whereas miR-141, miR-149 and miR-429 were downregulated in the ccRCC tissues (P<0.01). The expression of miR-221 and miR-211 was not significant in the ccRCC tissues (P>0.05). miR-34a, miR-21 and miR-224 were upregulated and miR-141 was downregulated in the sera of patients with ccRCC (P<0.01), while the expression of miR-149 and miR-429 was not significant (P>0.05). The serum miR-21 expression levels were significantly correlated with the clinical staging of the patients with ccRCC (P<0.05). miR-34a, miR-21 and miR-224 are upregulated in the tissues and sera of patients with ccRCC, whereas miR-141 is downregulated. miR-21 and miR-141 are associated with ccRCC and are, thus, potential ccRCC serum markers.
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An unusual porous metal-organic framework that demonstrates the highly efficient exchange of metal ions and the reversible adsorption of iodine.
Chem Asian J
PUBLISHED: 05-02-2013
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An exceedingly rare porous metal-organic framework that is based on cadmium ions and multi carboxylate ligands, namely, Na(0.25)[(CH3)2NH2](1.75)[Cd(L)2]·x solvent (1, H2L=2-hydroxymethyl-4,6-bi(2-methoxyl-4-(2-1-carboxyl)-ethlene)-1,3,5-mesitylene), has been successfully synthesized under solvothermal conditions. Compound 1 exhibits a 2D network that is constructed from left- and right-handed helical chains. Furthermore, neighboring 2D layers are stacked to give a porous motif. Strikingly, compound 1 exhibits the highly efficient exchange of metal ions from the main framework components whilst maintaining the structural integrity and the crystallinity of the network. In addition, Compound 1 also shows outstanding performance in the reversible adsorption of iodine.
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Induction of immune response and prevention of alveolar bone loss with recombinant Porphyromonas gingivalis peptidylarginine deiminase.
Arch. Oral Biol.
PUBLISHED: 04-22-2013
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Treatments for periodontitis are not absolutely perfect, and a vaccine against Porphyromonas gingivalis (P. gingivalis) could become a valuable adjunct therapy for periodontitis.
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Silica-based cerium (III) chloride nanoparticles prevent the fructose-induced glycation of ?-crystallin and H2O 2-induced oxidative stress in human lens epithelial cells.
Arch. Pharm. Res.
PUBLISHED: 03-27-2013
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This study aimed to investigate whether silica-cerium (III) chloride (CeCl3) nanoparticles could inhibit the formation of advanced glycation end-products (AGEs) and reduce oxidative stress. Silica-CeCl3 nanoparticles were synthesised by adsorption and embedment with micro-silica materials, forming uniform nanoparticles with a diameter of approximately 130 nm. Chaperone activity assays and AGEs formation assays, and intracellular reactive assays were adopted in this study to evaluate CeCl3 nanoparticles effect. UV-visible spectrometry showed that silica-CeCl3 nanoparticles at low concentrations rapidly formed tentatively stable conjugations with ?-crystallin, greatly enhancing the chaperone activity of ?-crystallin. Moreover, silica-CeCl3 nanoparticles markedly inhibited the fructose-induced glycation of ?-crystallin, showing an advantage over the control drugs aminoguanidine and carnosine. Silica-CeCl3 nanoparticles also reduced intracellular reactive oxygen species production and restored glutathione levels in H2O2-treated human lens epithelial cells. These findings suggest that silica-CeCl3 may be used as a novel agent for the prevention of cataractogenesis.
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A model of chlorophyll a fluorescence induction kinetics with explicit description of structural constraints of individual photosystem II units.
Photosyn. Res.
PUBLISHED: 02-27-2013
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Chlorophyll a fluorescence induction (FI) kinetics, in the microseconds to the second range, reflects the overall performance of the photosynthetic apparatus. In this paper, we have developed a novel FI model, using a rule-based kinetic Monte Carlo method, which incorporates not only structural and kinetic information on PSII, but also a simplified photosystem I. This model has allowed us to successfully simulate the FI under normal or different treatment conditions, i.e., with different levels of measuring light, under 3-(3,4-dichlorophenyl)-1,1-dimethylurea treatment, under 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone treatment, and under methyl viologen treatment. Further, using this model, we have systematically studied the mechanistic basis and factors influencing the FI kinetics. The results of our simulations suggest that (1) the J step is caused by the two-electron gate at the Q B site; (2) the I step is caused by the rate limitation of the plastoquinol re-oxidation in the plastoquinone pool. This new model provides a framework for exploring impacts of modifying not only kinetic but also structural parameters on the FI kinetics.
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Controllable syntheses of porous metal-organic frameworks: encapsulation of Ln(III) cations for tunable luminescence and small drug molecules for efficient delivery.
Chemistry
PUBLISHED: 01-15-2013
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Two porous metal-organic frameworks (MOFs), [Zn3 (L)(H2 O)2 ]?3?DMF?7?H2 O (MOF-1) and [(CH3 )2 NH2 ]6 [Ni3 (L)2 (H2 O)6 ]?3?DMF?15?H2 O (MOF-2), were synthesized solvothermally (H6 L=1,2,3,4,5,6-hexakis(3-carboxyphenyloxymethylene)benzene). In MOF-1, neighboring Zn(II) trimers are linked by the backbones of L ligands to form a fascinating 3D six-connected framework with the point symbol (4(12) .6(3) ) (4(12) .6(3) ). In MOF-2, eight L ligands bridge six Ni(II) atoms to generate a rhombic-dodecahedral [Ni6 L8 ] cage. Each cage is surrounded by eight adjacent ones through sharing of carboxylate groups to yield an unusual 3D porous framework. Encapsulation of Ln(III) cations for tunable luminescence and small drug molecules for efficient delivery were investigated in detail for MOF-1.
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Epigenetic Regulation of ?A-crystallin in High Myopia-Induced Dark Nuclear Cataract.
PLoS ONE
PUBLISHED: 01-01-2013
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To assess the etiology of early-onset dark nucleus in high-myopic patients and its relationship with the epigenetic regulation of ?A-crystallin (CRYAA).
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Association of the ephreceptor tyrosinekinase-type A2 (EPHA2) gene polymorphism rs3754334 with age-related cataract risk: a meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2013
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Recent clinical studies have assessed the association of various polymorphisms on the ephreceptor tyrosinekinase-type A2 (EPHA2) with the risk for age-related cataract in populations of different ethnic/racial backgrounds, but inconsistent results have been obtained.
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Insulin-producing cells derived from human embryonic stem cells: comparison of definitive endoderm- and nestin-positive progenitor-based differentiation strategies.
PLoS ONE
PUBLISHED: 01-01-2013
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Human embryonic stem cells (hESCs) are pluripotent and capable of undergoing multilineage differentiation into highly specialized cells including pancreatic islet cells. Thus, they represent a novel alternative source for targeted therapies and regenerative medicine for diabetes. Significant progress has been made in differentiating hESCs toward pancreatic lineages. One approach is based on the similarities of pancreatic ? cell and neuroepithelial development. Nestin-positive cells are selected as pancreatic ? cell precursors and further differentiated to secrete insulin. The other approach is based on our knowledge of developmental biology in which the differentiation protocol sequentially reproduces the individual steps that are known in normal ? cell ontogenesis during fetal pancreatic development. In the present study, the hESC cell line PKU1.1 was induced to differentiate into insulin-producing cells (IPCs) using both protocols. The differentiation process was dynamically investigated and the similarities and differences between both strategies were explored. Our results show that IPCs can be successfully induced with both differentiation strategies. The resulting IPCs from both protocols shared many similar features with pancreatic islet cells, but not mature, functional ? cells. However, these differently-derived IPC cell types displayed specific morphologies and different expression levels of pancreatic islet development-related markers. These data not only broaden our outlook on hESC differentiation into IPCs, but also extend the full potential of these processes for regenerative medicine in diabetes.
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Overexpressed DNA polymerase iota regulated by JNK/c-Jun contributes to hypermutagenesis in bladder cancer.
PLoS ONE
PUBLISHED: 01-01-2013
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Human DNA polymerase iota (pol ?) possesses high error-prone DNA replication features and performs translesion DNA synthesis. It may be specialized and strictly regulated in normal mammalian cells. Dysregulation of pol ? may contribute to the acquisition of a mutator phenotype. However, there are few reports describing the transcription regulatory mechanism of pol ?, and there is controversy regarding its role in carcinogenesis. In this study, we performed the deletion and point-mutation experiment, EMSA, ChIP, RNA interference and western blot assay to prove that c-Jun activated by c-Jun N-terminal kinase (JNK) regulates the transcription of pol ? in normal and cancer cells. Xeroderma pigmentosum group C protein (XPC) and ataxia-telangiectasia mutated related protein (ATR) promote early JNK activation in response to DNA damage and consequently enhance the expression of pol ?, indicating that the novel role of JNK signal pathway is involved in DNA damage response. Furthermore, associated with elevated c-Jun activity, the overexpression of pol ? is positively correlated with the clinical tumor grade in 97 bladder cancer samples and may contribute to the hypermutagenesis. The overexpressed pol ?-involved mutagenesis is dependent on JNK/c-Jun pathway in bladder cancer cells identifying by the special mutation spectra. Our results support the conclusion that dysregulation of pol ? by JNK/c-Jun is involved in carcinogenesis and offer a novel understanding of the role of pol ? or c-Jun in mutagenesis.
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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.