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Find video protocols related to scientific articles indexed in Pubmed.
Simultaneous Quantification of Protein Phosphorylation Sites using Liquid Chromatography-Tandem Mass Spectrometry-Based Targeted Proteomics: A Linear Algebra Approach for Isobaric Phosphopeptides.
J. Proteome Res.
PUBLISHED: 11-18-2014
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As one of the most studied post-translational modifications (PTM), protein phosphorylation plays an essential role in almost all cellular processes. Current methods are able to predict and determine thousands of phosphorylation sites, whereas stoichiometric quantification of these sites is still challenging. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS)-based targeted proteomics is emerging as a promising technique for site-specific quantification of protein phosphorylation using proteolytic peptides as surrogates of proteins. However, several issues may limit its application, one of which relates to the phosphopeptides with different phosphorylation sites and the same mass (i.e., isobaric phosphopeptides). While employment of site-specific product ions allows for these isobaric phosphopeptides to be distinguished and quantified, site-specific product ions are often absent or weak in tandem mass spectra. In this study, linear algebra algorithms were employed as an add-on to targeted proteomics to retrieve information on individual phosphopeptides from their common spectra. To achieve this simultaneous quantification, a LC-MS/MS-based targeted proteomics assay was first developed and validated for each phosphopeptide. Given the slope and intercept of calibration curves of phosphopeptides in each transition, linear algebraic equations were developed. Using a series of mock mixtures prepared with varying concentrations of each phosphopeptide, the reliability of the approach to quantify isobaric phosphopeptides containing multiple phosphorylation sites (?2) was discussed. Finally, we applied this approach to determine the phosphorylation stoichiometry of heat shock protein 27 (HSP27) at Ser78 and Ser82 in breast cancer cells and tissue samples.
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Chrysanthemyl diphosphate synthase operates in planta as a bifunctional enzyme with chrysanthemol synthase activity.
J. Biol. Chem.
PUBLISHED: 11-08-2014
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Chrysanthemyl diphosphate synthase (CDS) is the first pathway-specific enzyme in the biosynthesis of pyrethrins, the most widely used plant-derived pesticide. CDS catalyzes c1'-2-3 cyclopropanation reactions of two molecules of dimethylallyl diphosphate (DMAPP) to yield chrysanthemyl diphosphate (CPP). Three proteins are known to catalyze this cyclopropanation reaction of terpene precursors. Two of them, phytoene and squalene synthase, are bifunctional enzymes with both prenyltransferase and terpene synthase activity. CDS, the other member, was reported to perform only the prenyltransferase step. Here, we show that the NDXXD catalytic motif of CDS, under lower substrate conditions prevalent in plants, also catalyzes the next step converting CPP into chrysanthemol by hydrolyzing the diphosphate moiety. The enzymatic hydrolysis reaction followed conventional Michaelis-Menten kinetics, with a KM value for CPP of 196 ?M. For the chrysanthemol synthase activity, DMAPP competed with CPP as substrate. The DMAPP concentration required for half-maximal activity to produce chrysanthemol was ~100 ?M, and significant substrate inhibition was observed at elevated DMAPP concentrations. The N-terminal peptide of CDS was identified as a plastid targeting peptide. Transgenic tobacco plants overexpressing CDS emitted chrysanthemol at a rate of 0.12-0.16 ?g·h(-1)·g(-1) FW. We propose that CDS should be renamed a chrysanthemol synthase (CHS) utilizing DMAPP as substrate.
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Stimulation of the alpha 7 nicotinic acetylcholine receptor protects against neuroinflammation after tibia fracture and endotoxemia in mice.
Mol. Med.
PUBLISHED: 11-04-2014
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Surgery and critical illness often associate with cognitive decline. Surgical trauma or infection can independently lead to learning and memory impairments via similar, but not identical, cellular signaling of the innate immune system that promotes neuroinflammation. In this study we explored the putative synergism between aseptic orthopedic surgery and infection, the latter reproduced by postoperative lipopolysaccharide (LPS) administration. We observed that surgery and LPS augmented systemic inflammation up to postoperative day 3 and this was associated with further neuroinflammation (CD11b and CD68 immunoreactivity) in the hippocampus in mice compared to those received surgery or LPS alone. Administration of a selective alpha 7 subtype nicotinic acetylcholine receptor (?7 nAChR) agonist 2 hours after the LPS significantly improved neuroinflammation and hippocampal-dependent memory dysfunction. Modulation of nuclear factor-kappa B (NF?B) activation in monocytes and regulation of the oxidative stress response through nicotinamide adenine dinucleotide phosphate (NADPH) signaling appear to be key targets in modulating this response. Overall, these results suggest that it may be conceivable to limit and possibly prevent postoperative complications, including cognitive decline and/or infections, through stimulation of the cholinergic anti-inflammatory pathway.
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Diagnostic Errors in the Pediatric and Neonatal ICU: A Systematic Review.
Pediatr Crit Care Med
PUBLISHED: 10-21-2014
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Diagnostic errors lead to preventable hospital morbidity and mortality. ICU patients may be at particularly high risk for misdiagnosis. Little is known about misdiagnosis in pediatrics, including PICU and neonatal ICU. We sought to assess diagnostic errors in PICU and neonatal ICU settings by systematic review.
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NADPH Oxidase in the Renal Microvasculature Is a Primary Target for Blood Pressure-Lowering Effects by Inorganic Nitrate and Nitrite.
Hypertension
PUBLISHED: 10-15-2014
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Renal oxidative stress and nitric oxide (NO) deficiency are key events in hypertension. Stimulation of a nitrate-nitrite-NO pathway with dietary nitrate reduces blood pressure, but the mechanisms or target organ are not clear. We investigated the hypothesis that inorganic nitrate and nitrite attenuate reactivity of renal microcirculation and blood pressure responses to angiotensin II (ANG II) by modulating nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity and NO bioavailability. Nitrite in the physiological range (10(-7)-10(-5) mol/L) dilated isolated perfused renal afferent arterioles, which were associated with increased NO. Contractions to ANG II (34%) and simultaneous NO synthase inhibition (56%) were attenuated by nitrite (18% and 26%). In a model of oxidative stress (superoxide dismutase-1 knockouts), abnormal ANG II-mediated arteriolar contractions (90%) were normalized by nitrite (44%). Mechanistically, effects of nitrite were abolished by NO scavenger and xanthine oxidase inhibitor, but only partially attenuated by inhibiting soluble guanylyl cyclase. Inhibition of NADPH oxidase with apocynin attenuated ANG II-induced contractility (35%) similar to that of nitrite. In the presence of nitrite, no further effect of apocynin was observed, suggesting NADPH oxidase as a possible target. In preglomerular vascular smooth muscle cells and kidney cortex, nitrite reduced both basal and ANG II-induced NADPH oxidase activity. These effects of nitrite were also abolished by xanthine oxidase inhibition. Moreover, supplementation with dietary nitrate (10(-2) mol/L) reduced renal NADPH oxidase activity and attenuated ANG II-mediated arteriolar contractions and hypertension (99±2-146±2 mm Hg) compared with placebo (100±3-168±3 mm Hg). In conclusion, these novel findings position NADPH oxidase in the renal microvasculature as a prime target for blood pressure-lowering effects of inorganic nitrate and nitrite.
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Noninvasive Imaging of 3-dimensioal Myocardial Infarction from the Inverse Solution of Equivalent Current Density in Pathological Hearts.
IEEE Trans Biomed Eng
PUBLISHED: 09-24-2014
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We propose a new approach to non-invasively image the 3-dimensional myocardial infarction (MI) substrates based on equivalent current density (ECD) distribution that is estimated from the body surface potential maps (BSPMs) during S-T segment. The MI substrates were identified using a predefined threshold of ECD. Computer simulations were performed to assess the performance with respect to: 1) MI locations; 2) MI sizes; 3) measurement noise; 4) numbers of BSPM electrodes; and 5) volume conductor modeling errors. A total of 114 sites of transmural infarctions, 91 sites of epicardial infarctions, and 36 sites of endocardial infarctions were simulated. The simulation results show that: 1) Under 205 electrodes and 10 ?V noise, the averaged accuracies of imaging transmural MI are 83.4% for sensitivity, 82.2% for specificity, 65.0% for Dice's coefficient, and 6.5mm for distances between the centers of gravity (DCG). 2) For epicardial infarction, the averaged imaging accuracies are 81.6% for sensitivity, 75.8% for specificity, 45.3% for Dice's coefficient and 7.5mm for DCG; while for endocardial infarction, the imaging accuracies are 80.0% for sensitivity, 77.0% for specificity, 39.2% for Dice's coefficient, and 10.4mm for DCG. 3) A reasonably good imaging performance was obtained under higher noise levels, fewer BSPM electrodes, and mild volume conductor modeling errors. The present results suggest that this method has the potential to aid in the clinical identification of the MI substrates.
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Shell-Sheddable, pH-Sensitive Supramolecular Nanoparticles Based on Ortho Ester-Modified Cyclodextrin and Adamantyl PEG.
Biomacromolecules
PUBLISHED: 09-02-2014
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We report a new type of pH-sensitive supramolecular aggregates which possess a programmable character of sequential dePEGylation and degradation. As a platform of designing and building multifunctional supramolecular nanoparticles, a family of 6-OH ortho ester-modified ?-cyclodextrin (?-CD) derivatives have been synthesized via the facile reaction between ?-CD and cyclic ketene acetals with different alkyl lengths. These asymmetric acid-labile ?-CD derivatives formed amphiphilic supramolecules with adamantane-modified PEG through host-guest interaction in polar solvents such as ethanol. The supramolecules can self-assemble in water to form acid-labile supramolecular aggregates. The results of TEM and light scattering measurements demonstrate that the size and morphology of the aggregates are influenced by the alkyl or PEG length and the host-guest feed ratio. By carefully balancing the alkyl and PEG lengths and adjusting the host-guest ratio, well-dispersed vesicles (50-100 nm) or sphere-like nanoparticles (200-500 nm) were obtained. Zeta potential measurements reveal that these supramolecular aggregates are capable of being surface-functionalized via dynamic host-guest interaction. The supramolecular aggregates were stable at pH 8.4 for at least 12 h as proven by the (1)H NMR and LLS measurements. However, rapid dePEGylation occurred at pH 7.4 due to the hydrolysis of the ortho ester linkages locating at the interface, which resulted in aggregation of the dePEGylated hydrophobic inner cores. Upon further decreasing the pH to 6.4, the hydrophobic cores were further degraded due to the acid-accelerated hydrolysis of the ortho esters. The incubation stability of the acid-labile supramolecular aggregates in neutral buffer could be improved by incorporating hydrophobic poly(?-caprolactone) into the core of the aggregates.
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Prolonged neuroinflammation after lipopolysaccharide exposure in aged rats.
PLoS ONE
PUBLISHED: 08-29-2014
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Inflammation is a hallmark of several disease states ranging from neurodegeneration to sepsis but is also implicated in physiological processes like ageing. Non-resolving inflammation and prolonged neuroinflammation are unclear processes implicated in several conditions, including ageing. In this study we studied the long-term effects of endotoxemia, as systemic lipopolysaccharide (LPS) injection, focusing on the role of astrocyte activation and cytokine release in the brain of aged rats. A single dose of LPS (2 mg/kg) or 0.9% saline was injected intraperitoneally in aged rats. Levels of pro-inflammatory cytokines (TNF? and IL-1?) and NF-?B p65 activation were measured systemically and in hippocampal tissue. Astrocytes and cytokines release in the CNS were detected via double immunofluorescence staining at different time-points up to day 30. Serum levels of TNF? and IL-1? were significantly increased acutely after 30 minutes (p<0.001) and up to 6 hours (p<0.001) following LPS-injection. Centrally, LPS-treated rats showed up-regulated mRNA expression and protein levels of pro-inflammatory cytokines in the hippocampus. These changes associated with astrogliosis in the hippocampus dentate gyrus (DG), IL-1? immunoreactivity and elevated NF-?B p65 expression up to day 30 post LPS exposure. Overall, these data demonstrate that LPS induces prolonged neuroinflammation and astrocyte activation in the hippocampus of aged rats. Hippocampal NF-?B p65 and excessive astrocytes-derived IL-1? release may play a pivotal role in regulating long-lasting neuroinflammation.
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Tunable fractional-order differentiator using an electrically tuned silicon-on-isolator Mach-Zehnder interferometer.
Opt Express
PUBLISHED: 08-05-2014
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We propose and experimentally demonstrate a tunable fractional order photonic differentiator using an on-chip electrically tuned Mach-Zehnder interferometer (MZI) structure. The phase shift at the resonant frequency of the MZI varies when applying different voltages, which can implement the fractional differentiation. Due to the large 3-dB bandwidth of the MZI, the differentiator is expected to have an operation bandwidth of several hundred GHz. The proposed fractional order differentiator is demonstrated experimentally. A Gaussian-like pulse with a bandwidth of about 200 GHz is temporally differentiated with a tunable order range from 0.83 to 1.03.
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An integrative framework for sensor-based measurement of teamwork in healthcare.
J Am Med Inform Assoc
PUBLISHED: 07-24-2014
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There is a strong link between teamwork and patient safety. Emerging evidence supports the efficacy of teamwork improvement interventions. However, the availability of reliable, valid, and practical measurement tools and strategies is commonly cited as a barrier to long-term sustainment and spread of these teamwork interventions. This article describes the potential value of sensor-based technology as a methodology to measure and evaluate teamwork in healthcare. The article summarizes the teamwork literature within healthcare, including team improvement interventions and measurement. Current applications of sensor-based measurement of teamwork are reviewed to assess the feasibility of employing this approach in healthcare. The article concludes with a discussion highlighting current application needs and gaps and relevant analytical techniques to overcome the challenges to implementation. Compelling studies exist documenting the feasibility of capturing a broad array of team input, process, and output variables with sensor-based methods. Implications of this research are summarized in a framework for development of multi-method team performance measurement systems. Sensor-based measurement within healthcare can unobtrusively capture information related to social networks, conversational patterns, physical activity, and an array of other meaningful information without having to directly observe or periodically survey clinicians. However, trust and privacy concerns present challenges that need to be overcome through engagement of end users in healthcare. Initial evidence exists to support the feasibility of sensor-based measurement to drive feedback and learning across individual, team, unit, and organizational levels. Future research is needed to refine methods, technologies, theory, and analytical strategies.
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Case-Only Designs for Exploring the Interaction Between FCRL4 Gene and Suspected Environmental Factors in Patients with Ankylosing Spondylitis.
Inflammation
PUBLISHED: 07-12-2014
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The aim of this study was to explore the interaction between FCRL4 gene and environmental factors in patients with ankylosing spondylitis. Two hundred ninety-seven ankylosing spondylitis (AS) Han Chinese patients were selected who were diagnosed at the Department of Rheumatology, First Affiliated Hospital, Anhui Medical University, in accordance with the modified New York criteria. The single nucleotide polymorphism (SNP) was genotyped by multiplex SNaPshot technique. The interaction between FCRL4 gene and ten environmental factors in AS patients was assessed by using a case-only study. The interaction between FCRL4 gene (rs2777963) and environmental factors was analyzed by chi-square test and logistic models. p values, odds ratio, and 95 % confidence intervals (CIs) were used for estimating the effects of interaction. Odds ratio (OR) for the interaction of gene ×?environment (G?×?E) between drinking group and non-drinking group was 2.61 [95 % CI (1.30, 5.23), p?=?0.007], with statistical significance. Within the cooking oil group, there also may be an interaction of G?×?E between main animal oil and main plant oil [OR?=?10.55, 95 % CI (5.55, 20.04), p?
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[Effects of platelet-derived growth factor on the function of smooth muscle cells from different orders of pulmonary artery].
Zhonghua Jie He He Hu Xi Za Zhi
PUBLISHED: 07-12-2014
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To explore the functional responses of normal rat pulmonary artery smooth muscle cells (PASMCs) from different orders of pulmonary artery to the platelet-derived growth factor (PDGF).
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Optimization of reaction conditions by RSM and structure characterization of sulfated locust bean gum.
Carbohydr Polym
PUBLISHED: 06-21-2014
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Sulfated derivatives of galactomannan from locust bean gum (LBG) with the degree of substitution (DS) of 0.34-1.07 were synthesized using chlorosulfonic acid/pyridine (CSA/Py) method. Box-Behnken design (BBD) of response surface methodology (RSM) was employed to optimize the reaction conditions. Results of FT-IR and X-ray photoelectron spectroscopy (XPS) indicated that SO3H groups were widely present in sulfated LBG (SLBG). (13)C NMR result revealed that sulfation had occurred and C-6 substitution was predominant in SLBG. All sulfated samples showed a decrease in Mw and more broad molar mass distribution in size exclusion chromatography combined with laser light scattering (SEC-LLS) analysis. Results of MW - [Formula: see text] showed a decrease in fractal dimension (df) value. Laser light scattering results also showed a conformation transition from a compact chain conformation of branched clusters to a random coil conformation of SLBG. Compared to LBG and SLBG with low DS and molecular weight, SLBG2 exhibited an internal structure of random coil with a DS of 1.07. DS and molecular weight had great influence on its conformation in aqueous solution. Our results confirmed that the degradation of polysaccharide and SO3H groups improved significantly the stiffness of the chains due to the electrostatic effect.
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Synthesis and characterization of phosphorylated galactomannan: the effect of DS on solution conformation and antioxidant activities.
Carbohydr Polym
PUBLISHED: 06-19-2014
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Phosphorylated derivatives of galactomannan from guar gum (GG) with the degree of substitution (DS) of 0.35-0.52 were synthesized using POCl3/pyridine. FT-IR, (13)C NMR and XPS results revealed that phosphorylation had occurred and C-6 substitution was predominant in phosphorylated guar gum (PGG). PGG showed an increase in Mw and more broad molar mass distribution in size exclusion chromatography (SEC) analysis. Higher reaction temperature (above 60 °C) resulted in a higher MW value in PGG. It might be due to the cross-linking of polysaccharide chains by POCl3 via di-ester which was also supported by monosaccharide composition result. Results of M(W) - (S(2))(z)(1/2) showed a decrease in fractal dimension (df) values. DS had greater influence on its conformation in aqueous solution. The introduction of -PO3H2 groups improved significantly the stiffness of the chains due to the electrostatic effect. Furthermore, antioxidant experiments revealed that high DS could enhance the scavenging activities of radicals of PGG in vitro.
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Molecular cloning and differential expression analysis of a squalene synthase gene from Dioscorea zingiberensis, an important pharmaceutical plant.
Mol. Biol. Rep.
PUBLISHED: 06-17-2014
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Diosgenin is a steroid derived from cholesterol in plants and used as a typical initial intermediate for synthesis of numerous steroidal drugs in the world. Commercially, this compound is extracted mainly from the rhizomes or tubers of some Dioscorea species. Squalene synthase (SQS: EC 2.5.1.21) catalyzes the condensation of two molecules of farnesyl diphosphate to form squalene, the first committed step for biosynthesis of plant sterols including cholesterol, and is thought to play an important role in diosgenin biosynthesis. A full-length cDNA of a putative squalene synthase gene was cloned from D. zingiberensis and designated as DzSQS (Genbank Accession Number KC960673). DzSQS was contained an open reading frame of 1,230 bp encoding a polypeptide of 409 amino acids with a predicted molecular weight of 46 kDa and an isoelectric point of 6.2. The deduced amino acid sequence of DzSQS shared over 70 % sequence identity with those of SQSs from other plants. The truncated DzSQS in which 24 amino acids were deleted from the carboxy terminus was expressed in Escherichia coli, and the resultant bacterial crude extract was incubated with farnesyl diphosphate and NADPH. GC-MS analysis showed that squalene was detected in the in vitro reaction mixture. Quantitative real-time PCR analysis revealed that DzSQS was expressed from highest to lowest order in mature leaves, newly-formed rhizomes, young leaves, young stems, and two-year-old rhizomes of D. zingiberensis.
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Intraperitoneal chemotherapy for peritoneal carcinomatosis improves efficacy with acceptable safety: results of 200 cycles for 41 patients.
Hepatogastroenterology
PUBLISHED: 06-06-2014
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To investigate the efficacy and safety of intraperitoneal (IP) chemotherapy for peritoneal carcinomatosis (PC).
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Up-regulation of CNDP2 facilitates the proliferation of colon cancer.
BMC Gastroenterol
PUBLISHED: 05-14-2014
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Cytosolic nonspecific dipetidase (CN2) belongs to the family of M20 metallopeptidases. It was stated in previous articles that higher expression levels of CN2 were observed in renal cell carcinoma and breast cancer. Our study explored the correlation between CN2 and colon carcinogenesis.
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All-optical differential equation solver with constant-coefficient tunable based on a single microring resonator.
Sci Rep
PUBLISHED: 05-07-2014
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Photonic integrated circuits for photonic computing open up the possibility for the realization of ultrahigh-speed and ultra wide-band signal processing with compact size and low power consumption. Differential equations model and govern fundamental physical phenomena and engineering systems in virtually any field of science and engineering, such as temperature diffusion processes, physical problems of motion subject to acceleration inputs and frictional forces, and the response of different resistor-capacitor circuits, etc. In this study, we experimentally demonstrate a feasible integrated scheme to solve first-order linear ordinary differential equation with constant-coefficient tunable based on a single silicon microring resonator. Besides, we analyze the impact of the chirp and pulse-width of input signals on the computing deviation. This device can be compatible with the electronic technology (typically complementary metal-oxide semiconductor technology), which may motivate the development of integrated photonic circuits for optical computing.
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Development and validation of an ultra high performance liquid chromatography tandem mass spectrometry method for simultaneous determination of sulfonamides, quinolones and benzimidazoles in bovine milk.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 04-29-2014
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A simple, sensitive and reliable analytical method was developed for the simultaneous determination of 38 veterinary drugs (18 sulfonamides, 11 quinolones and 9 benzimidazoles) and 8 metabolites of benzimidazoles in bovine milk by ultra high performance liquid chromatography-positive electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS). Samples were extracted with acidified acetonitrile, cleaned up with Oasis(®) MCX cartridges, and analyzed by LC-MS/MS on an Acquity UPLC(®) BEH C18 column with gradient elution. The method allows such multi-analyte measurements within a 13min runtime while the specificity is ensured through the MRM acquisition mode. The method was validated according to the European Commission Decision 2002/657/EC determining specificity, decision limit (CC?), detection capability (CC?), recovery, precision, linearity and stability. For compounds which have MRLs in bovine milk, the CC? values fall into a range from 11 to 115?g/kg, and the CC? values fall within a range of 12-125?g/kg. For compounds which have not MRLs in bovine milk, the CC? values fall into a range from 0.01 to 0.08?g/kg, and the CC? values fall within a range of 0.02-0.11?g/kg. The mean recoveries of the 46 analytes were between 87 and 119%. The calculated RSD values of repeatability and within-laboratory reproducibility experiments were below 11% and 15% for the 46 compounds, respectively. The method was demonstrated to be suitable for the simultaneous determination of sulfonamides, quinolones and benzimidazoles in bovine milk.
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Simultaneous determination of amantadine, rimantadine and memantine in chicken muscle using multi-walled carbon nanotubes as a reversed-dispersive solid phase extraction sorbent.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 04-15-2014
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A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method using multi-walled carbon nanotubes (MWCNTs) as a reversed-dispersive solid phase extraction (r-dSPE) material combined with ultra-high liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was developed for the simultaneous determination of amantadine, rimantadine and memantine in chicken muscle. The satisfactory separation of isomers (rimantadine and memantine) was obtained on an Acquity BEH C18 column (2.1 mm × 100 mm, 1.7 ?m) after optimization of mobile phase composition, column temperature and flow rate. The method involved an acetonitrile-based sample preparation and a dSPE clean-up procedure with MWCNTs material. Variations in the type and amount of MWCNTs, the pH value of the extract, the extraction time for MWCNTs, and the type of eluent were used to determine the optimal parameters for increasing the sample throughput and the sensitivity. The samples were quantified using amantadine-D15, rimantadine-D4 and memantine-D6 as the internal standards. Under the optimized conditions, recoveries of 96.8-104.6% and the values of coefficient of variation (CV) of 3.8-6.4% were obtained for the three drugs in chicken muscle at three spiked levels (0.5, 1.0 and 1.5 ?g/kg), and the decision limits (CC?) and detection capabilities (CC?) were 0.15-0.20 ?g/kg and 0.20-0.25 ?g/kg, respectively. Positive results were obtained from local supermarket using this method, and the concentrations obtained from the newly developed method compared well to the previously reported method.
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Systematic analysis of the association between gut flora and obesity through high-throughput sequencing and bioinformatics approaches.
Biomed Res Int
PUBLISHED: 04-11-2014
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Eighty-one stool samples from Taiwanese were collected for analysis of the association between the gut flora and obesity. The supervised analysis showed that the most, abundant genera of bacteria in normal samples (from people with a body mass index (BMI) ? 24) were Bacteroides (27.7%), Prevotella (19.4%), Escherichia (12%), Phascolarctobacterium (3.9%), and Eubacterium (3.5%). The most abundant genera of bacteria in case samples (with a BMI ? 27) were Bacteroides (29%), Prevotella (21%), Escherichia (7.4%), Megamonas (5.1%), and Phascolarctobacterium (3.8%). A principal coordinate analysis (PCoA) demonstrated that normal samples were clustered more compactly than case samples. An unsupervised analysis demonstrated that bacterial communities in the gut were clustered into two main groups: N-like and OB-like groups. Remarkably, most normal samples (78%) were clustered in the N-like group, and most case samples (81%) were clustered in the OB-like group (Fisher's P??value = 1.61E - 07). The results showed that bacterial communities in the gut were highly associated with obesity. This is the first study in Taiwan to investigate the association between human gut flora and obesity, and the results provide new insights into the correlation of bacteria with the rising trend in obesity.
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Increased frequency of circulating follicular helper T cells in patients with ankylosing spondylitis.
Mod Rheumatol
PUBLISHED: 04-11-2014
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Objective. The relationship between circulating follicular helper T (Tfh) cells and ankylosing spondylitis (AS) remains unclear. The aims of our study were to measure the levels of circulating Tfh cells and several related parameters in patients with AS, and examine the correlation of these factors with disease activity. Methods. We designated CD4 + CXCR5 + ICOS+ T cells as circulating Tfh cells. The percentage of circulating Tfh cells was detected using flow cytometry. Plasma IL-21 and immunoglobulin (IgA, IgM, and IgG) levels were quantified using enzyme-linked immunosorbent assay in 60 AS patients and 60 healthy controls (HC). Results. The percentage of circulating Tfh cells was increased in AS patients compared with that in HC. As AS patients were divided into active and inactive groups, the percentage of circulating Tfh cells was significantly increased in active group compared with both inactive group and HC. Plasma IL-21 and immunoglobulin levels were elevated in AS patients, and the differences were significant except IgG. In addition, the percentage of circulating Tfh cells was positively correlated with Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and plasma IL-21 levels were positively correlated with plasma immunoglobulin levels. But neither circulating Tfh cells nor BASDAI was significantly correlated with plasma IL-21 and immunoglobulin levels in AS patients, with the exception of significant correlation between BASDAI and plasma IgM levels in active AS patients. Conclusion. Our study has shown the increased percentage of circulating Tfh cells correlated with disease activity, and the high plasma IL-21 levels were associated with high plasma immunoglobulin levels in patients with AS, indicating that the circulating Tfh cells may be associated with the development of AS.
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High-fluoride promoted phagocytosis-induced apoptosis in a matured ameloblast-like cell line.
Arch. Oral Biol.
PUBLISHED: 04-09-2014
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Endocytosis and phagocytosis are important physiologic activities occurring during ameloblast differentiation. We have previously found that excess fluoride inhibited ameloblasts endocytotic functions. Here, we hypothesized that increasing amounts of fluoride may affect ameloblast phagocytotic function during their differentiation. Using cell culture, we first induced maturation of the mouse ameloblast-like LS8 cells by treatment with exogenous retinoic acid (RA) and dexamethasone (DEX). We measured their phagocytotic activity by fluorescent microscopy using a live cell visualization station. We found that ameloblast-like LS8 cells matured with RA/DEX treatment and the increasing amounts of fluoride demonstrated the up-regulated expression of the phagocytotic marker proteins, LAMP1 and CD68. A connection between phagocytosis and apoptosis was confirmed by the increased number of phagocytotic vacuole-like structures and the heterochromatin margination phenomenon observed in the RA/DEX with NaF treatment group. The increase in albumin uptake by ameloblasts was confirmed using whole organ culture of incisor tooth germs. Here, in fluoride treated tooth germs, mature canonical ameloblasts showed greater amounts of albumin uptake, which was accompanied by decreased expression of the anti-apoptosis marker, Bcl-2 along with up-regulated expression of CD68. From these observations, we inferred that high doses of fluoride may cause apoptosis by increasing the phagocytosis of protein particles in mature-stage ameloblasts and loss of Bcl-2 signals might be involved in this process.
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A liquid chromatography-tandem mass spectrometry-based targeted proteomics assay for monitoring P-glycoprotein levels in human breast tissue.
Clin. Chim. Acta
PUBLISHED: 03-27-2014
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P-glycoprotein (P-gp) can efflux drugs from cancer cells, and its overexpression is commonly associated with multi-drug resistance (MDR). Thus, the accurate quantification of P-gp would help predict the response to chemotherapy and for prognosis of breast cancer patients.
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Association between KIR polymorphisms and ankylosing spondylitis in populations: A meta-analysis.
Mod Rheumatol
PUBLISHED: 03-27-2014
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Abstract Objectives. Published association studies of killer cell immunoglobulin-like receptors (KIRs) and ankylosing spondylitis (AS) in populations are inconsistent. The aim of this study is to determine whether the KIR polymorphisms confer susceptibility to AS in populations by conducting a meta-analysis. Methods. A computer search was carried out up to August 2013 for literature pertaining to AS and KIR polymorphisms. Publications addressing the association between the KIR polymorphisms and susceptibility to AS in populations were selected from the Pubmed, Elsevier Science Direct, China National Knowledge Infrastructure (CNKI) and Chinese Biomedical Literature Database (CBM) databases. The odds ratio (OR) with 95% confidence interval (95%CI) was calculated. Results. A total of 13 case-control studies in 9 articles were included in this meta-analysis. Meta-analysis results identified two positive associations of 2DS4 and 3DS1 with susceptibility to AS in populations. In subgroup analysis, there was a positive association between 2DS4 and susceptibility to AS in Asians, but not in Caucasians. And there were associations between 3DL1, 3DS1 and susceptibility to AS in Caucasians, but not in Asians. Results of subgroup analysis also showed that there were associations between 2DL5, 2DS4, 2DS5, 3DL1, 3DS1 and susceptibility to AS in HLA-B*27-positive patients and HLA-B*27-positive healthy controls. Conclusions. This meta-analysis confirms that 2DS4 and 3DS1 might be potential risk factors for AS in populations.
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Glucose-responsive hydrogels based on dynamic covalent chemistry and inclusion complexation.
Soft Matter
PUBLISHED: 03-21-2014
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A novel glucose-responsive hydrogel system based on dynamic covalent chemistry and inclusion complexation was described. Hydrogels are formed by simply mixing the solutions of three components: poly(ethylene oxide)-b-poly vinyl alcohol (PEO-b-PVA) diblock polymer, ?-cyclodextrin (?-CD) and phenylboronic acid (PBA)-terminated PEO crosslinker. Dynamic covalent bonds between PVA and PBA provide sugar-responsive crosslinking, and the inclusion complexation between PEO and ?-CD can promote hydrogel formation and enhance hydrogel stability. The ratios of the three components have a remarkable effect on the gelation time and the mechanical properties of the final gels. In rheological measurements, the hydrogels are demonstrated to possess solid-like behaviour and good structural recovery ability after yielding. The sugar-responsiveness of the hydrogels was examined by protein loading and release experiments, and the results indicate that this property is also dependent on the compositions of the gels; at a proper component ratio, a new glucose-responsive hydrogel system operating at physiological pH can be obtained. The combination of good biocompatibility of the three components and the easy preparation of hydrogels with tunable glucose-responsiveness may enable an alternative design of hydrogel systems that finds potential applications in biomedical and pharmaceutical fields, such as treatment of diabetes.
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XELIRI compared with FOLFIRI as a second-line treatment in patients with metastatic colorectal cancer.
Oncol Lett
PUBLISHED: 03-06-2014
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The aim of this study was to compare the efficacy, safety and survival rate of a treatment regimen comprising capecitabine plus irinotecan (XELIRI) to those of a standard regimen comprising leucovorin, fluorouracil and irinotecan (FOLFIRI), to determine the correlation among the inherited genetic variations in UGT1A1, UGT1A7 and UGT1A9. A total of 84 consecutive patients with histologically confirmed metastatic colorectal cancer (mCRC) were included in the study. All patients were treated with FOLFIRI or XELIRI. The median progression-free survival time was 4.4 months for FOLFIRI and 5.7 months for XELIRI (hazard ratio=1.35; 95% confidence interval, 0.83-2.21; P=0.22). When compared with FOLFIRI (6.34%), XELIRI was associated with lower rates of severe toxicity (3.29) (P=0.026) and similar disease control rates (69.57% for FOLFIRI and 61.11% for XELIRI; P=0.49). In total, 17 single nucleotide polymorphisms were identified, five of which revealed an association with grade 3/4 neutropenia, including UGT1A7*4; however, UGT1A1*28 and UGT1A1*6, which have been previously reported, were not significant. Additionally, H2 haplotypes, which include UGT1A9*22, and H5 and H7 haplotypes, which include UGT1A7*2, UGT1A7*3 and UGT1A7*4, were associated with a higher risk of severe neutropenia. In conclusion, XELIRI is an effective treatment regimen with acceptable response rates and tolerability for mCRC patients as a second-line treatment. Furthermore, inherited genetic variations in UGT1A1, UGT1A7 and UGT1A9 are associated with grade 3/4 neutropenia.
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EOLA1 protects lipopolysaccharide induced IL-6 production and apoptosis by regulation of MT2A in human umbilical vein endothelial cells.
Mol. Cell. Biochem.
PUBLISHED: 02-28-2014
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Endothelial cell (EC) injury or dysfunction is believed to be mediated at least in part by lipopolysaccharide (LPS). Recent studies have shown that LPS induces apoptosis in different types of endothelium, including HUVEC. Previously we used EOLA1 (endothelial-overexpressed LPS-associated factor 1) cDNA as a bait and performed a yeast two-hybrid screening of a human liver cDNA library and identified metallothionein 2a (MT2a) as the associated protein. EOLA1 protein plays a role as a signal transduction factor. But the mechanism of EOLA1 mediated the protection of cell production of IL-6 and apopotosis in HUVEC is not known. MT2a is expressed in many kinds of cells and plays a role in inflammation. In this study, we demonstrated that LPS could induce EOLA1 expression in time-dependent and apparently contributed to the inhibition of IL-6 production and apoptosis induced by LPS treatment. We also found that deletion of EOLA1 promoted IL-6 production and apoptosis in the treatment of LPS in HUVEC. Furthermore, we demonstrated that MT2a was activated by LPS, and played a key role in LPS-induced IL-6 expression in HUVEC. We further provided the evidence that EOLA1 functioned as a negative regulator for LPS response by regulation of MT2a. These findings suggest that EOLA1 may have an important regulatory role during EC inflammatory responses.
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Influence of a multifaceted intervention on central line days in intensive care units: results of a national multisite study.
Am J Infect Control
PUBLISHED: 02-15-2014
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Removing unnecessary central lines is a critical step in reducing risk of infection and was 1 focus of a national quality improvement collaborative. We examined if participating adult intensive care units (ICUs) reduced central line days during the project period compared with the period before implementation of the "On the CUSP: Stop BSI" program.
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An ovarian cancer model with positive ER: Reversion of ER antagonist resistance by Src blockade.
Oncol. Rep.
PUBLISHED: 02-14-2014
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Approximately 60% of ovarian cancers are positive for the estrogen receptor (ER); however, ER-targeted treatment is disappointing due to drug resistance as compared with breast cancer. In estrogen-sensitive cancers, estrogen activates Src to phosphorylate p27 promoting its degradation and increasing cell cycle progression. Since Src is frequently activated in ovarian cancers, we investigated whether combined Src and ER blockade by saracatinib and fulvestrant would circumvent anti-estrogen resistance. In 20 out of 40 enrolled patients with immunohistochemically ER-positive ovarian cancer, phosphorylated Src (p-Src) at the site of 416 tyrosine was expressed with a propensity for metastasis and a poorer disease-free survival (DFS) at 3 years following ER antagonist treatment. The effects of ER and Src blockade on cell cycle were assayed in estrogen receptor ? (ER?)-positive ovarian cancer. We observed that Src activity was fairly greater in anti-estrogen-resistant ovarian cancer cells than that in the anti-estrogen-sensitive cell line. Estrogen activated Src via ER-Src binding and ER translocation from cytoplasm to nucleus. Mitogenesis was mediated via ER?, not ER?. Combined saracatinib and fulvestrant increased p27 and inhibited cell cycle progression. Furthermore, dual therapy induced autophagy and inhibited ovarian cancer xenograft growth more effectively than monotherapy. Saracatinib facilitated the therapeutic effects of fulvestrant by antagonizing the estrogen-mediated Src activation. These are supportive of further preclinical assessment of combined fulvestrant and saracatinib in patients with ovarian cancer.
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HCC cells with high levels of Bcl-2 are resistant to ABT-737 via activation of the ROS-JNK-autophagy pathway.
Free Radic. Biol. Med.
PUBLISHED: 02-09-2014
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The Bcl-2 inhibitor ABT-737 has shown promising antitumor efficacy in vivo and in vitro. However, some reports have demonstrated that HCC cells are resistant to ABT-737, and the corresponding molecular mechanisms of this resistance are not well known. In this study, we found that HCC cells with high levels of Bcl-2 were markedly resistant to ABT-737 compared to HCC cells with low levels of Bcl-2. In HCC cells with high levels of Bcl-2 (such as HepG2 cells), ABT-737 induced protective autophagy via the sequential triggering of reactive oxygen species (ROS) accumulation, short-term activation of JNK, enhanced phosphorylation of Bcl-2, and dissociation of Beclin 1 from the Bcl-2/Beclin 1 complex. Moreover, autophagy suppressed the overactivation of the ROS-JNK pathway and protected against apoptosis. In HCC cells with low levels of Bcl-2 (i.e., Huh7 cells), ABT-737 induced apoptosis via the sequential stimulation of ROS, sustained activation of JNK, enhanced translocation of Bax from the cytosol to the mitochondria, and release of cytochrome c. In sum, this study indicated that the activation of the ROS-JNK-autophagy pathway may be an important mechanism by which HCC cells with high levels of Bcl-2 are resistant to ABT-737.
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Impact of self-reported guideline compliance: Bloodstream infection prevention in a national collaborative.
Am J Infect Control
PUBLISHED: 02-08-2014
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We sought to examine self-reported compliance with 5 evidence-based central line-associated bloodstream infection (CLABSI) prevention practices and link compliance to CLABSI rates in a national patient safety collaborative.
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An investigation of heat shock protein 27 and P-glycoprotein mediated multi-drug resistance in breast cancer using liquid chromatography-tandem mass spectrometry-based targeted proteomics.
J Proteomics
PUBLISHED: 02-08-2014
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One missing puzzle piece to study heat shock protein 27 (HSP27) in P-glycoprotein (P-gp) mediated multi-drug resistance (MDR) was the amount of HSP27 and the extent of its phosphorylation in the biological context. Liquid chromatography-tandem mass spectrometry (LC/MS/MS)-based targeted proteomics allows researchers to monitor associated proteins and their modification simultaneously and quantitatively. In this study, a targeted proteomics assay was first developed and validated for the quantification of HSP27 and its phosphorylated forms. Using this assay, the level of HSP27 was determined in non-tumoral cells MCF-10A, parental drug-sensitive cancer cells MCF-7/WT and drug-resistant cancer cells MCF-7/ADR. A decrease of HSP27 expression was observed in P-gp overexpressed MCF-7/ADR cells. A quantitative time-course analysis of both HSP27 and P-gp in doxorubicin (DOX)-treated MCF-7/WT cells also implied that HSP27 may participate in the P-gp modulation. Furthermore, stoichiometry of site-specific HSP27 phosphorylation indicated that DOX treatment rapidly induced the HSP27 phosphorylation at Ser82. Moreover, conventional analytical methods were also performed for a comparison.
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Soluble A? oligomers are rapidly sequestered from brain ISF in vivo and bind GM1 ganglioside on cellular membranes.
Neuron
PUBLISHED: 02-07-2014
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Soluble A? oligomers contribute importantly to synaptotoxicity in Alzheimer's disease, but their dynamics in vivo remain unclear. Here, we found that soluble A? oligomers were sequestered from brain interstitial fluid onto brain membranes much more rapidly than nontoxic monomers and were recovered in part as bound to GM1 ganglioside on membranes. A? oligomers bound strongly to GM1 ganglioside, and blocking the sialic acid residue on GM1 decreased oligomer-mediated LTP impairment in mouse hippocampal slices. In a hAPP transgenic mouse model, substantial levels of GM1-bound A??? were recovered from brain membrane fractions. We also detected GM1-bound A? in human CSF, and its levels correlated with A???, suggesting its potential as a biomarker of A?-related membrane dysfunction. Together, these findings highlight a mechanism whereby hydrophobic A? oligomers become sequestered onto GM1 ganglioside and presumably other lipids on neuronal membranes, where they may induce progressive functional and structural changes.
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Infant 7-valent pneumococcal conjugate vaccine immunization alters young adulthood CD4(+)T cell subsets in allergic airway disease mouse model.
Vaccine
PUBLISHED: 02-06-2014
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7-Valent pneumococcal conjugate vaccine (PCV7) immunization in adulthood can inhibit allergic asthma in mouse model. The aim of this study is to investigate the effects of infant PCV7 immunization on young adulthood CD4(+)T cell subsets in a murine allergic airway disease (AAD) model. Our study indicated that infant PCV7 immunization can inhibit young adulthood airway inflammation and airway hyperresponsiveness (AHR) by inducing the production of Foxp3(+)Treg, Th1 cells and their cytokines IL-10 and IFN-?, inhibiting the production of Th2, Th17 cells and their cytokines IL-13 and IL-17A in BALB/c mice model. These results suggested that infant PCV7 immunization may serve as an effective measure to prevent young adulthood mice AAD.
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Overexpression of RAGE contributes to cigarette smoke-induced nitric oxide generation in COPD.
Lung
PUBLISHED: 01-31-2014
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Receptor for advanced glycation end products (RAGE), a multiple-ligands receptor, is implicated in chronic obstructive pulmonary disease (COPD). This study was designed to investigate the potential role of RAGE in nitric oxide (NO) generation, an endogenous marker of nitrosative stress in COPD.
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Decreased bone marrow stromal cells activity involves in unilateral anterior crossbite-induced early subchondral bone loss of temporomandibular joints.
Arch. Oral Biol.
PUBLISHED: 01-29-2014
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Subchondral bone loss in mandibular condyles was reported to be induced by experimentally created unilateral anterior crossbite (UAC) which altered the occlusal load distribution and hereafter the temporomandibular joint (TMJ) remodelling process. However, the initial cellular responses are poorly understood. In the present study, changes in osteoblast and osteoclast activities in TMJ subchondral bone were investigated using the rats treated with UAC.
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Hormone profiling and transcription analysis reveal a major role of ABA in tomato salt tolerance.
Plant Physiol. Biochem.
PUBLISHED: 01-25-2014
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The response and adaptation of plants to different environmental stresses are of great interest as they provide the key to understanding the mechanisms underlying stress tolerance. In this study, the changing patterns of four endogenous hormones and various physiological and biochemical parameters of both a salt-tolerant (LA2711) and a salt-sensitive (ZS-5) tomato cultivar were examined under salt stress and non-stress conditions. Additionally, the transcription of key genes in the abscisic acid (ABA) biosynthesis and metabolism were analyzed at different time points. The results indicated that gene expression responsible for ABA biosynthesis and metabolism coincided with the hormone level, and SlNCED1 and SlCYP707A3 may play major roles in the process. LA2711 performed superior to ZS-5 on various parameters, including seed germination, Na(+) compartmentation, selective absorption of K(+), and antioxidant enzymes activity. The difference in salt tolerance between the two genotypes could be attributed to the different levels of ABA due to differences in gene expression of key genes in ABA biosynthesis and metabolism. Although gibberellin, cytokinin and auxin were involved, our results indicated that ABA signaling plays a major role in tomato salt tolerance. As compared to ZS-5, LA2711 had a higher capability to selectively absorb and redistribute K(+) and a higher tolerance to Na(+) in young leaves, which may be the main physiological mechanisms of salt tolerance.
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Resolvin-D1 inhibits interleukin-8 and hydrogen peroxide production induced by cigarette smoke extract in 16HBE cells via attenuating NF-?B activation.
Chin. Med. J.
PUBLISHED: 01-24-2014
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Cigarette smoke induced airway inflammation plays a role in pathogenesis of airway inflammation. Resolvin-D1 derived from omega-3 polyunsaturated fatty acids is an endogenous anti-inflammatory and proresolving lipid mediator. Resolvin-D1 ameliorated inflammatory responses in lung injury, asthma, peritonitis and atherosclerosis. We investigated whether resolvin-D1 suppressed the productions of chemokines and oxidative stress induced by cigarette smoke extract (CSE) in vitro and its possible mechanism.
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Highly porous structure strategy to improve the SnO2 electrode performance for lithium-ion batteries.
Phys Chem Chem Phys
PUBLISHED: 01-23-2014
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SnO2 is a promising high-capacity anode material for lithium-ion batteries (LIBs), but it usually exhibits poor cycling stability due to its huge volume variation during the lithium uptake and release process. In this work, SnO2 nanofibers and nanotubes with highly porous (HPNFs, HPNTs) structure have been synthesized by a facile emulsion electrospinning and subsequent calcination process in air at 500 °C. Pores with a diameter range of 2-30 nm were distributed evenly on the surface of the nanofibers and nanotubes. The HPNFs and HPNTs manifested high capacities and excellent cycle performance as the anode electrode for LIBs, and they can deliver reversible capacities of 583 and 645 mA h g(-1) at a current density of 100 mA g(-1) after 50 cycles, respectively. When the current density is up to 5 A g(-1), the electrodes still exhibit a good retention, and the reversible capacities were about 370 and 432 mA h g(-1), which performs much better than the nanofibers and nanotubes without a porous structure. Our results demonstrated that this simple method could be extended for the synthesis of porous metal oxide nanotubes with high performances in the applications of lithium ion batteries and other fields.
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A liquid chromatography-tandem mass spectrometry-based targeted proteomics approach for the assessment of transferrin receptor levels in breast cancer.
Proteomics Clin Appl
PUBLISHED: 01-21-2014
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Overexpression of human transferrin receptor (TfR) has been described qualitatively in various cancers, including breast cancer. Since TfR is also expressed to some extent under normal physiological conditions, increase of specificity and reproducibility in TfR quantification could improve the early detection and prognostic evaluation of cancers.
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High-performance liquid chromatography assay with programmed flow elution for cisatracurium in human plasma: application to pharmacokinetics in infants and children.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-19-2014
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A high-performance liquid chromatography (HPLC) assay with fluorescence detection (FLD) for quantification of cisatracurium in human plasma was developed and fully validated. Liquid-liquid extraction was employed for sample preparation. The separation was carried out on a C18 column with ternary mobile phase composed of 30mmolL(-1) phosphate buffer (pH 3.0), acetonitrile and methanol (60:35:5, v/v/v). Verapamil was used as the internal standard. The isocratic elution with programmed flow rate was employed by setting at 0.8mLmin(-1) from 0 to 3.5min, 0.5mLmin(-1) from 3.5 to 6min, and 1.0mLmin(-1) from 6 to 10min. The fluorescence detection was performed at 236nm for excitation and 324nm for emission. The assay was linear from 50 to 2800ngmL(-1), with a detection limit of 12ngmL(-1). The correlation coefficient (r) for linear regression was 0.9997. The intra-day coefficients of variation (CVs) were less than 2.0%, and the inter-day CVs were less than 4.0%. The mean recoveries were in the range of 92.1-100.4%. The total HPLC run time was less than 10min. The developed HPLC method was fast, simple, sensitive, accurate and suitable for studying the pharmacokinetics of cisatracurium in infants and children after intravenous administration.
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Can cholesterol be used to distinguish pleural exudates from transudates? evidence from a bivariate meta-analysis.
BMC Pulm Med
PUBLISHED: 01-16-2014
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Many studies have investigated whether pleural cholesterol levels can aid in diagnosis of pleural exudates, and the results have varied considerably. To gain a more reliable answer to this question, we meta-analyzed the literature on using pleural cholesterol or the ratio of cholesterol in pleural fluid to cholesterol in serum (P/S cholesterol ratio) as diagnostic tests to help identify pleural exudates.
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Experimental observation of optical differentiation and optical Hilbert transformation using a single SOI microdisk chip.
Sci Rep
PUBLISHED: 01-14-2014
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Optical differentiation and optical Hilbert transformation play important roles in communications, computing, information processing and signal analysis in optical domain offering huge bandwidth. Meanwhile, silicon-based photonic integrated circuit is one of the most promising candidates for all-optical signal processing due to its intrinsic advantages of low power consumption, compact footprint, ultra-high speed and compatibility with electronic integrated circuits. In this study, we analyze the interrelation between first-order optical differentiation and optical Hilbert transformation and then experimentally demonstrate a feasible integrated scheme which can simultaneously function as first-order optical differentiation and optical Hilbert transformation based on a single microdisk resonator. This finding may motivate the development of integrated optical signal processors.
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Clinical detection of human probiotics and human pathogenic bacteria by using a novel high-throughput platform based on next generation sequencing.
J Clin Bioinforma
PUBLISHED: 01-13-2014
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The human body plays host to a vast array of bacteria, found in oral cavities, skin, gastrointestinal tract and the vagina. Some bacteria are harmful while others are beneficial to the host. Despite the availability of many methods to identify bacteria, most of them are only applicable to specific and cultivable bacteria and are also tedious. Based on high throughput sequencing technology, this work derives 16S rRNA sequences of bacteria and analyzes probiotics and pathogens species.
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Discovery of Tertiary Amine and Indole Derivatives as Potent ROR?t Inverse Agonists.
ACS Med Chem Lett
PUBLISHED: 01-09-2014
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A novel series of tertiary amines as retinoid-related orphan receptor gamma-t (ROR?t) inverse agonists was discovered through agonist/inverse agonist conversion. The level of ROR?t inhibition can be enhanced by modulating the conformational disruption of H12 in ROR?t LBD. Linker exploration and rational design led to the discovery of more potent indole-based ROR?t inverse agonists.
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Two new susceptibility loci 1q24.2 and 11p11.2 confer risk to severe acne.
Nat Commun
PUBLISHED: 01-09-2014
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Severe acne is a chronic inflammatory skin disorder characterized by widespread inflammatory lesions including nodules, cysts and potential scarring. Here we perform the first genome-wide association study of severe acne in a Chinese Han population comprising 1,056 cases and 1,056 controls using the Illumina HumanOmniZhongHua-8 BeadChip. In an independent cohort of 1,860 cases and 3,660 controls of Chinese Han, we replicate 101 SNPs of which 3 showed consistent association. We identify two new susceptibility loci at 11p11.2 (DDB2, rs747650, P(combined)=4.41 × 10?? and rs1060573, P(combined)=1.28 × 10??) and 1q24.2 (SELL, rs7531806, P(combined)=1.20 × 10??) that are involved in androgen metabolism, inflammation processes and scar formation in severe acne. These results point to new genetic susceptibility factors and suggest several new biological pathways related to severe acne.
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The effects of different crossing-linking conditions of genipin on type I collagen scaffolds: an in vitro evaluation.
Cell Tissue Bank
PUBLISHED: 01-07-2014
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The purpose of this paper is to analyze the properties of fabricating rat tail type I collagen scaffolds cross-linked with genipin under different conditions. The porous genipin cross-linked scaffolds are obtained through a two step freeze-drying process. To find out the optimal cross-link condition, we used different genipin concentrations and various cross-linked temperatures to prepare the scaffolds in this study. The morphologies of the scaffolds were characterized by scanning electron microscope, and the mechanical properties of the scaffolds were evaluated under dynamic compression. Additionally, the cross-linking degree was assessed by ninhydrin assay. To investigate the swelling ratio and the in vitro degradation of the collagen scaffold, the tests were also carried out by immersion of the scaffolds in a PBS solution or digestion in a type I collagenase respectively. The morphologies of the non-cross-linked scaffolds presented a lattice-like structure while the cross-linked ones displayed a sheet-like framework. The morphology of the genipin cross-linked scaffolds could be significantly changed by either increasing genipin concentration or the temperature. The swelling ratio of each cross-linked scaffold was much lower than that of the control (non-cross-linked).The ninhydrin assay demonstrated that the higher temperature and genipin concentration could obviously increase the cross-linking efficiency. The in vitro degradation studies indicated that genipin cross-linking can effectively elevate the biostability of the scaffolds. The biocompatibility and cytotoxicity of the scaffolds was evaluated by culturing rat chondrocytes on the scaffold in vitro and by MTT. The results of MTT and the fact that the chondrocytes adhered well to the scaffolds demonstrated that genipin cross-linked scaffolds possessed an excellent biocompatibility and low cytotoxicity. Based on these results, 0.3 % genipin concentrations and 37 °C cross-linked temperatures are recommended.
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Discovery of novel N-(5-(arylcarbonyl)thiazol-2-yl)amides and N-(5-(arylcarbonyl)thiophen-2-yl)amides as potent ROR?t inhibitors.
Bioorg. Med. Chem.
PUBLISHED: 01-07-2014
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Novel series of N-(5-(arylcarbonyl)thiazol-2-yl)amides and N-(5-(arylcarbonyl)thiophen-2-yl)amides were discovered as potent retinoic acid receptor-related orphan receptor-gamma-t (ROR?t) inhibitors. SAR studies of the ROR?t HTS hit 6a led to identification of thiazole ketone amide 8h and thiophene ketone amide 9g with high binding affinity and inhibitory activity of Th17 cell differentiation. Compound 8h showed in vivo efficacy in both mouse experimental autoimmune encephalomyelitis (EAE) and collagen induced arthritis (CIA) models via oral administration.
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MiR-21 inhibits c-Ski signaling to promote the proliferation of rat vascular smooth muscle cells.
Cell. Signal.
PUBLISHED: 01-07-2014
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Previously, we reported that the decrease of endogenous c-Ski expression is implicated in the progression of vascular smooth muscle cell (VSMC) proliferation after arterial injury. However, the molecular mechanism of the down-regulation of c-Ski is not clear. In this study, a potential miR-21 recognition element was identified in the 3'-untranslated region (UTR) of rat c-Ski mRNA. A reporter assay revealed that miR-21 could recognize the miR-21 recognition element of c-Ski mRNA. In A10 rat aortic smooth muscle cells, overexpression of miR-21 significantly inhibited the expression of c-Ski protein and promoted cell proliferation, which could be blocked by inhibition of miR-21 or overexpression of c-Ski. Further investigation demonstrated that the effect of miR-21 on VSMC proliferation resulted from negative regulation of c-Ski to suppress p38-p21/p27 signaling, the downstream pathway of c-Ski in VSMCs. These results indicate that c-Ski is a target gene of miR-21. miR-21 specifically binds to the 3'-untranslated region of c-Ski and negatively regulates c-Ski expression to diminish the protective effects of c-Ski and stimulate VSMC proliferation in the progression of arterial injury.
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Determinants of health-related quality of life worsening in patients with chronic obstructive pulmonary disease at one year.
Chin. Med. J.
PUBLISHED: 01-04-2014
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Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide and has been the leading cause of death in China. Patients with COPD have significant decrements in their health-related quality of life (HRQL). It is necessary to identify the factors involved in worsening HRQL in order to improve the HRQL of COPD patients. However, evidence from longitudinal studies is limited. The aim of the study was to evaluate the determinants of the deterioration of HRQL in patients with COPD.
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Effect of dietary physically effective fiber on ruminal fermentation and the fatty acid profile of milk in dairy goats.
J. Dairy Sci.
PUBLISHED: 01-02-2014
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The objective of this experiment was to characterize the relationship among rumen fermentation variables, milk fatty acid profile, and dietary physically effective neutral detergent fiber (peNDF) content in a study that controlled for the potential confounding effects of dissimilar dry matter intake among treatments. Ten multiparous Xinong Saanen dairy goats were divided into 2 groups with 2 ruminally cannulated goats per group. Goats in each group were assigned to 1 of 2 dietary treatments (high and low peNDF) according to a 2×2 crossover design with 2 periods. The peNDF content of alfalfa hay (proportion of neutral detergent fiber retained on an 8.0-mm screen) was 42.1% for the high-peNDF and 14.5% for the low-peNDF group. To ensure similar dry matter intake, each morning the amount of alfalfa hay consumed on the prior day by the high-peNDF group was determined (amount offered minus morning refusals), and this was the amount of hay offered to the low-peNDF group that day. Each adaptation period consisted of 21d, followed by a 9-d sampling period. Dry matter intake and milk production and composition were similar between treatments. Milk energy efficiency increased with low dietary peNDF. Duration of pH below 5.60 was longer for goats fed the low-peNDF ration compared with the high-peNDF ration (4.08 vs. 0.41h/d); however, mean rumen pH (6.05 vs. 6.13) was not different between treatments. Reducing dietary peNDF increased rumen total volatile fatty acids (114.6 vs. 95.1mM) and decreased chewing time (404 vs. 673min/d), but did not affect the ratios of acetate, propionate, and butyrate. The relative abundance of Fibrobacter succinogenes and Ruminococcus flavefaciens increased with reduced dietary peNDF, but Ruminococcus albus proportions were not influenced by treatment. Reducing dietary peNDF decreased the proportion of iso C14:0, iso C15:0, and trans-11 C18:1 in milk fat, whereas the iso C17:0 and trans-10 C18:1 increased. This study demonstrated that low dietary peNDF in dairy goats increases rumen volatile fatty acids, reduces chewing time, and is correlated to the amount of F. succinogenes and R. flavefaciens.
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Bacterial communities in semen from men of infertile couples: metagenomic sequencing reveals relationships of seminal microbiota to semen quality.
PLoS ONE
PUBLISHED: 01-01-2014
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Some previous studies have identified bacteria in semen as being a potential factor in male infertility. However, only few types of bacteria were taken into consideration while using PCR-based or culturing methods. Here we present an analysis approach using next-generation sequencing technology and bioinformatics analysis to investigate the associations between bacterial communities and semen quality. Ninety-six semen samples collected were examined for bacterial communities, measuring seven clinical criteria for semen quality (semen volume, sperm concentration, motility, Kruger's strict morphology, antisperm antibody (IgA), Atypical, and leukocytes). Computer-assisted semen analysis (CASA) was also performed. Results showed that the most abundant genera among all samples were Lactobacillus (19.9%), Pseudomonas (9.85%), Prevotella (8.51%) and Gardnerella (4.21%). The proportion of Lactobacillus and Gardnerella was significantly higher in the normal samples, while that of Prevotella was significantly higher in the low quality samples. Unsupervised clustering analysis demonstrated that the seminal bacterial communities were clustered into three main groups: Lactobacillus, Pseudomonas, and Prevotella predominant group. Remarkably, most normal samples (80.6%) were clustered in Lactobacillus predominant group. The analysis results showed seminal bacteria community types were highly associated with semen health. Lactobacillus might not only be a potential probiotic for semen quality maintenance, but also might be helpful in countering the negative influence of Prevotella and Pseudomonas. In this study, we investigated whole seminal bacterial communities and provided the most comprehensive analysis of the association between bacterial community and semen quality. The study significantly contributes to the current understanding of the etiology of male fertility.
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Diagnostic value of survivin for malignant pleural effusion: a clinical study and meta-analysis.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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To investigate the diagnostic accuracy of survivin for malignant pleural effusion (MPE).
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c-Ski inhibits autophagy of vascular smooth muscle cells induced by oxLDL and PDGF.
PLoS ONE
PUBLISHED: 01-01-2014
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Autophagy is increasingly being recognized as a critical determinant of vascular smooth muscle cell (VSMC) biology. Previously, we have demonstrated that c-Ski inhibits VSMC proliferation stimulated by transforming growth factor ? (TGF-?), but it is not clear whether c-Ski has the similar protective role against other vascular injury factors and whether regulation of autophagy is involved in its protective effects on VSMC. Accordingly, in this study, rat aortic A10 VSMCs were treated with 40 µg/ml oxidized low-density lipoprotein (oxLDL) or 20 ng/ml platelet-derived growth factor (PDGF), both of which were autophagy inducers and closely related to the abnormal proliferation of VSMCs. Overexpression of c-Ski in A10 cells significantly suppressed the oxLDL- and PDGF- induced autophagy. This action of c-Ski resulted in inhibiting the cell proliferation, the decrease of contractile phenotype marker ?-SMA expression while the increase of synthetic phenotype marker osteopontin expression stimulated by oxLDL or PDGF. Inversely, knockdown of c-Ski by RNAi enhanced the stimulatory effects of oxLDL or PDGF on A10 cell growth and phenotype transition. And further investigation found that inhibition of AKT phosphorylation to downregulate proliferating cell nuclear antigen (PCNA) expression, was involved in the regulation of autophagy and associated functions by c-Ski in the oxLDL- and PDGF-stimulated VSMCs. Collectively, c-Ski may play an important role in inhibiting autophagy to protect VSMCs against some harsh stress including oxLDL and PDGF.
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Nuclear export of L-periaxin, mediated by its nuclear export signal in the PDZ domain.
PLoS ONE
PUBLISHED: 01-01-2014
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Myelinating Schwann cells specifically express L-periaxin (L-PRX) in the mammalian peripheral nervous system. Several loss-of-function mutations in periaxin have been described and linked to autosomal recessive Dejerine Sottas neuropathy and to demyelinating Charcot-Marie-Tooth disease. The localization of L-periaxin is developmentally regulated in the nucleus and the plasma membrane of Schwann cells. In this study, L-periaxin, which contains a PDZ domain, a nuclear localization signal (NLS) domain, a repeat domain, and an acidic domain, was localized in the cytoplasm of RSC96 cells. By contrast, a mutant L-periaxin with a deleted PDZ domain was localized mainly in the nucleus of RSC96 cells. After a nuclear cyclin A1, which is localized exclusively in the nucleus, was fused with the PDZ domain, cyclinA1was found in the cytoplasm of RSC96 cells. Treatment with leptomycin B (LMB), a specific inhibitor of nuclear export mediated by leucine-rich nuclear export signal (NES), also causes nuclear accumulation of wild-type L-periaxin. Double leucine mutation (L83, 85Q) in the putative NES in the PDZ domain prevented L-periaxin nuclear export and induced nuclear accumulation. These results suggested that the localization of L-periaxin in the cytoplasm is supported by NES in the PDZ domain.
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Diagnostic performance of lung ultrasound in the diagnosis of pneumonia: a bivariate meta-analysis.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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Pneumonia is a common disease with both high morbidity and mortality, the diagnosis of pneumonia remains a clinical challenge. Many studies have been conducted to identify the usefulness of lung ultrasound for the diagnosis of pneumonia, but with inconsistent and inconclusive results. The present study aimed to establish the overall diagnostic accuracy of lung ultrasound in diagnosing pneumonia.
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ICAM-1 +469 A/G polymorphism and cancer risk: a meta-analysis involving 9375 subjects.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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The ICAM-1 +469 A/G polymorphism has been implicated in susceptibility to cancer, but the results were inconclusive. The present meta-analysis aimed to investigate the association between the ICAM-1 +469 A/G polymorphism and cancer risk.
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The photoconversion of gamma-hexachlorocyclohexane under UV irradiation in water, snow and ice.
Water Sci. Technol.
PUBLISHED: 12-17-2013
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The photochemistry of organic pollutants has received increasing attention in ice and snow. In this work, the photoconversion of gamma-hexachlorocyclohexane (?-HCH) under UV irradiation was investigated in water, snow and ice. The photoconversion rate, products and mechanisms were inspected, and the effect of inorganic ions (NO2(-), NO3(-), HCO3(-) and Fe(2+)) was discussed. The results showed that ?-HCH could be photoconverted in water, snow and ice, with the photoconversion rate being fastest in snow, and slowest in ice. All photoconversion could be described by the first-order kinetics model. In water, snow and ice, the common photoproducts of ?-HCH were alpha-hexachlorocyclohexane (?-HCH) and pentachlorocyclohexene. ?-HCH was generated by a change in the bonding of a chlorine atom in ?-HCH; pentachlorocyclohexene was generated by the removal of a molecule of chlorine hydride from a molecule of ?-HCH. Different concentrations of NO2(-), NO3(-) and HCO3(-) all inhibited the photoconversion of ?-HCH, and the inhibition effect decreased with increasing concentrations of NO2(-) and NO3(-), but increased with the increasing concentrations of HCO3(-). Different concentrations of Fe(2+) promoted the photoconversion of ?-HCH in water and ice, but had little effect in snow.
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Eliminating central line-associated bloodstream infections: a national patient safety imperative.
Infect Control Hosp Epidemiol
PUBLISHED: 11-26-2013
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Background.?Several studies demonstrating that central line-associated bloodstream infections (CLABSIs) are preventable prompted a national initiative to reduce the incidence of these infections. Methods.?We conducted a collaborative cohort study to evaluate the impact of the national "On the CUSP: Stop BSI" program on CLABSI rates among participating adult intensive care units (ICUs). The program goal was to achieve a unit-level mean CLABSI rate of less than 1 case per 1,000 catheter-days using standardized definitions from the National Healthcare Safety Network. Multilevel Poisson regression modeling compared infection rates before, during, and up to 18 months after the intervention was implemented. Results.?A total of 1,071 ICUs from 44 states, the District of Columbia, and Puerto Rico, reporting 27,153 ICU-months and 4,454,324 catheter-days of data, were included in the analysis. The overall mean CLABSI rate significantly decreased from 1.96 cases per 1,000 catheter-days at baseline to 1.15 at 16-18 months after implementation. CLABSI rates decreased during all observation periods compared with baseline, with adjusted incidence rate ratios steadily decreasing to 0.57 (95% confidence intervals, 0.50-0.65) at 16-18 months after implementation. Conclusion.?Coincident with the implementation of the national "On the CUSP: Stop BSI" program was a significant and sustained decrease in CLABSIs among a large and diverse cohort of ICUs, demonstrating an overall 43% decrease and suggesting the majority of ICUs in the United States can achieve additional reductions in CLABSI rates.
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Nickel nanoparticle decorated graphene for highly selective isolation of polyhistidine-tagged proteins.
Nanotechnology
PUBLISHED: 11-22-2013
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Nickel nanoparticle decorated graphene (GP-Ni) is prepared by one-pot hydrothermal reduction of graphene oxide and nickel cations by hydrazine hydrate in the presence of poly(sodium-p-styrenesulfonate) (PSS). The GP-Ni hybrid is characterized by XRD, TEM, SEM, XPS, Raman and FT-IR spectra, demonstrating the formation of poly-dispersed nickel nanoparticles with an average size of 83 nm attached on the surface of graphene sheets. The GP-Ni hybrid exhibits ferromagnetic behavior with a magnetization saturation of 31.1 emu g(-1) at 10?000 Oersted (Oe). The GP-Ni also possesses favorable stability in aqueous medium and rapid magnetic response to an external magnetic field. These make it a novel magnetic adsorbent for the separation/isolation of His6-tagged recombinant proteins from a complex sample matrix (cell lysate). The targeted protein species is captured onto the surface of the GP-Ni hybrid via specific metal affinity force between polyhistidine groups and nickel nanoparticles. The SDS-PAGE assay indicates highly selective separation of His6-tagged Smt A from cell lysate. The GP-Ni hybrid displays favorable performance on the separation/isolation of His6-tagged recombinant proteins with respect to the commercial NTA-Ni(2+) column.
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Electrochemical Properties of Nanostructured Copper Hydroxysulfate Mineral Brochantite upon Reaction with Lithium.
Nano Lett.
PUBLISHED: 11-18-2013
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Cu-containing conversion electrodes have received much study as high capacity electrodes for lithium-ion batteries, but many suffer from poor reversibility. The electrochemical properties of the copper hydroxysulfate compound, Cu4(OH)6SO4, more commonly known as the mineral brochantite and as a patina constituent on the Statue of Liberty, were investigated. Nanostructured brochantite was synthesized using precipitation and microwave-assisted hydrothermal reactions and evaluated in half-cells with Li metal counter electrodes. Reversible capacities >400 mAh/g corresponding to the 2 electron reduction of Cu(2+) and discharge potential of 1.8 V versus Li/Li(+) were observed in brochantite with a nanoplate morphology. Detailed characterization using X-ray diffraction, scanning and transmission electron microscopy, and X-ray photoelectron spectroscopy was performed to better understand the conversion process.
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[The value of changes in end-tidal carbon dioxide pressure induced by passive leg raising test in predicting fluid responsiveness in mechanically ventilated patients with septic shock].
Zhonghua Nei Ke Za Zhi
PUBLISHED: 11-09-2013
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To test whether the changes of partial end-tidal carbon dioxide pressure (PETCO2) during passive leg raising (PLR) predict fluid responsiveness in mechanically ventilated patients with septic shock.
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Permethrin resistance variation and susceptible reference line isolation in a field population of the mosquito, Culex quinquefasciatus (Diptera: Culicidae).
Insect Sci.
PUBLISHED: 10-22-2013
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This study examines the genetic variations and mechanisms involved in the development of permethrin resistance in individual mosquitoes from a field population of Culex quinquefasciatus, HAmCq(G0) , and characterizes susceptible reference lines of mosquitoes with a similar genetic background to the field HAmCq(G0) strain. Six upregulated cytochrome P450 genes, CYP9M10, CYP9J34, CYP6P14, CYP9J40, CYP6AA7, and CYP4C52v1, previously identified as being upregulated in the larvae of resistant HAmCq(G8) mosquitoes were examined in the larvae of 3 strains (susceptible S-Lab, parental HAmCq(G0) and permethrin-selected highly resistant HAmCq(G8) ) and 8 HAmCq(G0) single-egg raft colonies, covering a range of levels of susceptibility/resistance to permethrin and exhibiting different variations in the expression of A and/or T alleles at the L-to-F kdr locus of the sodium channel. The 2 lines with the lowest tolerance to permethrin and bearing solely the susceptible A allele at the L-to-F kdr locus of the sodium channels, from colonies Cx_SERC5 and Cx_SERC8, showed lower or similar levels of all 6 of the P450 genes tested compared with the S-Lab strain, suggesting that these 2 lines could be used as the reference mosquitoes in future studies characterizing insecticide resistance in HAmCq mosquitoes. This study also provides a detailed investigation of the mechanisms involved in insecticide resistance in individuals within a population: individuals with elevated levels of resistance to permethrin all displayed one or more potential resistance mechanisms-either elevated levels of P450 gene expression, or L-to-F mutations in the sodium channel, or both.
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Building a business case for colorectal surgery quality improvement.
Dis. Colon Rectum
PUBLISHED: 10-10-2013
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Improving surgical quality is a priority, but building a business case for the efforts could be challenging. Bridging the gap between the clinicians and hospital leaders is the first step to align quality and financial priorities within health care.
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An Evaluation of Ventilator-Associated Pneumonia Process Measure Sampling Strategies in a Surgical ICU.
Am J Med Qual
PUBLISHED: 09-23-2013
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Ventilator-associated pneumonia (VAP) is common, lethal, and expensive. Little is known about optimal strategies to evaluate process measures for VAP prevention. The authors conducted a prospective study of different sampling strategies for evaluating head of bed (HOB) elevation and oral care. There was no significant difference between morning and evening shift HOB elevation compliance rates (P = .47). If oral care was performed at least once during a 12-hour shift, there was an 87% probability that it also was performed at least twice. If oral care was performed at least twice during a 12-hour shift, then there was a 93% probability that chlorhexidine oral care was performed at least once. The results of this study suggest that sampling HOB elevation twice as compared with once daily is unlikely to change the estimate of performance, oral care need not be frequently sampled, and high oral care compliance may predict chlorhexidine oral care compliance.
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Rapamycin regulates connective tissue growth factor expression of lung epithelial cells via phosphoinositide 3-kinase.
Exp. Biol. Med. (Maywood)
PUBLISHED: 08-28-2013
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The pathogenesis of idiopathic pulmonary fibrosis (IPF) remains largely unknown. It is believed that IPF is mainly driven by activated alveolar epithelial cells that have a compromised migration capacity, and that also produce substances (such as connective tissue growth factor, CTGF) that contribute to fibroblast activation and matrix protein accumulation. Because the mechanisms regulating these processes are unclear, the aim of this study was to determine the role of rapamycin in regulating epithelial cell migration and CTGF expression. Transformed epithelial cell line A549 and normal human pulmonary alveolar or bronchial epithelial cells were cultured in regular medium or medium containing rapamycin. Real time reverse transcriptase polymerase chain reaction was employed to determine CTGF mRNA expression. Western blotting and an enzyme-linked immunosorbent assay were used for detecting CTGF protein. Wound healing and migration assays were used to determine the cell migration potential. Transforming growth factor (TGF)-? type I receptor (T?RI) inhibitor, SB431542 and phosphoinositide 3-kinase (PI3K) inhibitor, LY294002 were used to determine rapamycins mechanism of action. It was found that treatment of A549 and normal human alveolar or bronchial epithelial cells with rapamycin significantly promoted basal or TGF-?1 induced CTGF expression. LY294002, not SB431542 attenuated the promotional effect of rapamycin on CTGF expression. Cell mobility was not affected by rapamycin in wound healing and migration assays. These data suggest rapamycin has a profibrotic effect in vitro and underscore the potential of combined therapeutic approach with PI3K and mammalian target of rapamycin inhibitors for the treatment of animal or human lung fibrosis.
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Role of microRNA-27a in myoblast differentiation.
Cell Biol. Int.
PUBLISHED: 07-17-2013
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MicroRNAs (miRNAs) are a class of endogenous non-coding RNAs that are critically involved in roles in various aspects of skeletal myogenesis. microRNA miR-27a promotes myoblast proliferation by targeting myostatin, a critical inhibitor of skeletal muscle development, but its mode of action in myoblast differentiation remains unclear. We have found that expression of miR-27a and myostatin were upregulated and downregulated, respectively, during myoblast differentiation. Overexpression of miR-27a increased the number of myosin heavy chain (MHC)-positive cells and upregulated mRNA and protein of MyoD and myogenin. These findings indicate that miR-27a plays a role in enhancing myoblast differentiation.
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Investigation of maternal environmental exposures in association with self-reported preterm birth.
Reprod. Toxicol.
PUBLISHED: 07-16-2013
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Identification of maternal environmental factors influencing preterm birth risks is important to understand the reasons for the increase in prematurity since 1990. Here, we utilized a health survey, the US National Health and Nutrition Examination Survey (NHANES) to search for personal environmental factors associated with preterm birth. 201 urine and blood markers of environmental factors, such as allergens, pollutants, and nutrients were assayed in mothers (range of N: 49 to 724) who answered questions about any children born preterm (delivery <37 weeks). We screened each of the 201 factors for association with any child born preterm adjusting by age, race/ethnicity, education, and household income. We attempted to verify the top finding, urinary bisphenol A, in an independent study of pregnant women attending Lucile Packard Childrens Hospital. We conclude that the association between maternal urinary levels of bisphenol A and preterm birth should be evaluated in a larger epidemiological investigation.
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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.