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Find video protocols related to scientific articles indexed in Pubmed.
Acetylation Preserves Retinal Ganglion Cell Structure and Function in a Chronic Model of Ocular Hypertension.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 11-01-2014
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Purpose: The current studies investigate if the histone deacetylase (HDAC) inhibitor, valproic acid (VPA), can limit retinal ganglion cell (RGC) degeneration in an ocular hypertensive rat model Methods: Intraocular pressure (IOP) was elevated unilaterally in Brown Norway rats by hypertonic saline injection. Rats received either vehicle or VPA (100 mg/kg) treatment for 28 days. RGC function and number was assessed by pattern electroretinogram (pERG) and retrograde FluoroGold-labeling. Western blotting and a fluorescence assay were used for determination of histone-H3 acetylation and HDAC activity, respectively, at 3-days, 1-week, and 2-week time points. Results: Hypertonic saline injections increased IOPs by 7-14 mmHg. In vehicle-treated animals, ocular hypertension resulted in a 29.1% and 39.4% decrease in pERG amplitudes at 2- and 4-weeks, respectively, and a 42.9% decrease in mean RGC density at 4-weeks. In comparison, VPA-treatment yielded significant amplitude preservation at 2- and 4-weeks, and showed significant RGC density preservation at 4-weeks. No significant difference in RGC densities or IOPs was measured between control eyes of vehicle- and VPA-treated rats. In ocular-hypertensive eyes, Class-I HDAC activity was significantly elevated within 1-week (13.3 ± 2.2%) and histone-H3 acetylation was significantly reduced within 2-weeks following the induction of ocular hypertension. Conclusions: Increase in HDAC activity is a relatively early retinal event induced by elevated IOP and suppressing HDAC activity can protected RGCs from ocular-hypertensive stress. Together these data provide a basis for developing HDAC inhibitors for the treatment of optic neuropathies.
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Injury-induced MRP8/MRP14 stimulates IP-10/CXCL10 in monocytes/macrophages.
FASEB J.
PUBLISHED: 10-25-2014
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Trauma/hemorrhagic shock is associated with morbidity and mortality due to dysregulated inflammation, which is driven in part by monocytes/macrophages stimulated by injury-induced release of damage-associated molecular pattern (DAMP) molecules. MRP8/MRP14 is an endogenous DAMP involved in various inflammatory diseases, though its mechanism of action is unclear. Circulating MRP8/MRP14 levels in human blunt trauma nonsurvivors were significantly lower than those of survivors (P < 0.001). Human monocytic THP-1 cells stimulated with MRP8/MRP14 expressed the chemokine IFN-? inducible protein 10 (IP-10)/CXCL10. Circulating IP-10 levels in human blunt trauma patients were correlated positively with MRP8/MRP14 levels (r = 0.396, P < 0.001), and were significantly lower in trauma nonsurvivors than in survivors (P < 0.001). We therefore sought to determine the mechanisms by which MRP8/MRP14 stimulates IP-10 in monocytes/macrophages, and found that induction of IP-10 by MRP8/MRP14 required Toll-like receptor 4 and TRIF but not MyD88. Full induction of IP-10 by MRP8/MRP14 required synergy between the transcription factors NF-?B and IFN regulatory factor 3 (IRF3). The receptor for IP-10 is CXCR3, and MRP8/MRP14-induced chemotaxis of CXCR3(+) cells was dependent on the production of IP-10 in monocytes/macrophages. Furthermore, in vivo study with a mouse trauma/hemorrhagic shock model showed that administration of neutralizing antibody against MRP8 prevented activation of NF-?B and IRF3 as well as IP-10 production. Thus, the current study identified a novel signaling mechanism that controls IP-10 expression in monocytes/macrophages by MRP8/MRP14, which may play an important role in injury-induced inflammation.-Wang, J., Vodovotz, Y., Fan, L., Li, Y., Liu, Z., Namas, R., Barclay, D., Zamora, R., Billiar, T. R., Wilson, M. A., Fan, J., Jiang, Y. Injury-induced MRP8/MRP14 stimulates IP-10/CXCL10 in monocytes/macrophages.
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[Helicobacter pylori infection and associated risk factors in Chengdu].
Sichuan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 10-25-2014
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OBJECTIVE : To investigate the prevalence of Helicobacter pylori (Hp) infection in Chengdu and its risk factors.
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High Current Density and Longtime Stable Field Electron Transfer from Large-Area Densely Arrayed Graphene Nanosheet-Carbon Nanotube Hybrids.
ACS Appl Mater Interfaces
PUBLISHED: 10-23-2014
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Achieving high current and longtime stable field emission from large area (larger than 1 mm(2)), densely arrayed emitters is of great importance in applications for vacuum electron sources. We report here the preparation of graphene nanosheet-carbon nanotube (GNS-CNT) hybrids by following a process of iron ion prebombardment on Si wafers, catalyst-free growth of GNSs on CNTs, and high-temperature annealing. Structural observations indicate that the iron ion prebombardment influences the growth of CNTs quite limitedly, and the self-assembled GNSs sparsely distributed on the tips of CNTs with their sharp edges unfolded outside. The field emission study indicates that the maximum emission current density (Jmax) is gradually promoted after these treatments, and the composition with GNSs is helpful for decreasing the operation fields of CNTs. An optimal Jmax up to 85.10 mA/cm(2) is achieved from a 4.65 mm(2) GNS-CNT sample, far larger than 7.41 mA/cm(2) for the as-grown CNTs. This great increase of Jmax is ascribed to the reinforced adhesion of GNS-CNT hybrids to substrates. We propose a rough calculation and find that this adhesion is promoted by 7.37 times after the three-step processing. We consider that both the ion prebombardment produced rough surface and the wrapping of CNT foot by catalyst residuals during thermal processing are responsible for this enhanced adhesion. Furthermore, the three-step prepared GNS-CNT hybrids present excellent field emission stability at high emission current densities (larger than 20 mA/cm(2)) after being perfectly aged.
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The Anti-apoptotic Effect of Polypeptide from Chlamys farreri (PCF) in UVB-Exposed HaCaT Cells Involves Inhibition of iNOS and TGF-?1.
Cell Biochem. Biophys.
PUBLISHED: 10-22-2014
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To investigate the molecular mechanisms of polypeptide from Chlamys farreri (PCF)'s anti-apoptotic effect, HaCaT cells were exposed to 20 mJ/CM(2) UVB, with or without pretreatment of TGF-?1 antagonist SB431542, inducible nitric oxide synthase (iNOS) inhibitor S-methylisothiourea sulfate (SMT), nitric oxide scavenger carboxy-PTIO, or 1.42, 2.84, and 5.69 mM PCF, or iNOS transfection (without UVB exposure). Apoptosis was confirmed with Hoechst 33258 staining; RT-PCR and western blot were used to determine the expression levels of iNOS and TGF-?1 signaling pathway. Both UVB exposure and iNOS transfection-induced apoptosis in UVB-exposed HaCat cells, while PCF, SB431542, SMT, and carboxy-PTIO all inhibited UVB-induced apoptosis. TGF-?1, Smad4, and Smad7 mRNA levels were all altered, similarly, iNOS, TGF-?1, and pSmad2/3 protein levels were all altered in UVB-exposed HaCaT cells. In pretreated cells, SB431542, SMT, carboxy-PTIO, and 1.42-5.69 mM PCF all inhibited UVB-induced apoptosis. Moreover, PCF treatment inhibited the expression levels of iNOS, TGF-?1, pSmad2/3, and Smad4, while increased the expression level of Smad7. SB431542 did not significantly alter iNOS expression, while SMT and carboxy-PTIO significantly altered TGF-?1 signaling level. The anti-apoptotic effect of PCF in UVB-exposed HaCaT cells involves the inhibition of iNOS expression and subsequently inhibition of TGF-?1 signaling pathway.
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Addition of optically pure H-phosphinate to ketones: selectivity, stereochemistry and mechanism.
Org. Biomol. Chem.
PUBLISHED: 10-20-2014
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Aromatic methyl ketones and cyclic asymmetric ketones underwent hydrophosphorylation with P-stereogenic H-P species in the presence of potassium carbonate to produce P,C-stereogenic tertiary ?-hydroxyl phosphinates in excellent yields with up to 99?:?1 dr. The diastereoselectivity was induced by a reversible conversion of less stable stereomer of product to that of a more stable one via an equilibrium, which was confirmed by aldehyde/ketone exchanging reaction. Toward the exchange, aliphatic or aldehyde carbonyl were more active than aromatic or ketone carbonyls, respectively. The stability difference between the two diastereomers was controlled by the sizes of substituents linking to phosphorus or ?-carbon.
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Neutrophils counteract autophagy-mediated anti-inflammatory mechanisms in alveolar macrophage: role in posthemorrhagic shock acute lung inflammation.
J. Immunol.
PUBLISHED: 09-29-2014
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Acute lung injury (ALI) is a major component of multiple organ dysfunction syndrome after hemorrhagic shock (HS) resulting from major surgery and trauma. The increased susceptibility in HS patients to the development of ALI suggests not yet fully elucidated mechanisms that enhance proinflammatory responses and/or suppress anti-inflammatory responses in the lung. Alveolar macrophages (AM?) are at the center of the pathogenesis of ALI after HS. We have previously reported that HS-activated polymorphonuclear neutrophils (PMNs) interact with macrophages to influence inflammation progress. In this study, we explore a novel function of PMNs regulating AM? anti-inflammatory mechanisms involving autophagy. Using a mouse "two-hit" model of HS/resuscitation followed by intratracheal injection of muramyl dipeptide, we demonstrate that HS initiates high mobility group box 1/TLR4 signaling, which upregulates NOD2 expression in AM? and sensitizes them to subsequent NOD2 ligand muramyl dipeptide to augment lung inflammation. In addition, upregulated NOD2 signaling induces autophagy in AM?, which negatively regulates lung inflammation through feedback suppression of NOD2-RIP2 signaling and inflammasome activation. Importantly, we further demonstrate that HS-activated PMNs that migrate in alveoli counteract the anti-inflammatory effect of autophagy in AM?, possibly through NAD(P)H oxidase-mediated signaling to enhance I-?B kinase ? phosphorylation, NF-?B activation, and nucleotide-binding oligomerization domain protein 3 inflammasome activation, and therefore augment post-HS lung inflammation. These findings explore a previously unidentified complexity in the mechanisms of ALI, which involves cell-cell interaction and receptor cross talk.
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Sub-10 nm Au-Pt-Pd alloy trimetallic nanoparticles with a high oxidation-resistant property as efficient and durable VOC oxidation catalysts.
Chem. Commun. (Camb.)
PUBLISHED: 08-22-2014
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Sub-10 nm AuPtPd alloy trimetallic nanoparticles (TMNPs) with a high oxidation-resistant property were prepared by photo-deposition followed by a high temperature (700-900 °C) air annealing process.
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Surgical treatment of metachronous second primary lung cancer.
Ann. Thorac. Surg.
PUBLISHED: 08-16-2014
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Many studies have demonstrated that patients with metachronous second primary lung cancer (MSPLC) benefit from surgery. Owing to the lack of uniform criteria and prospective randomized trials, the extent of resection remains controversial, and prognostic factors are still not fully clear. The present study aimed to assess surgical treatment of MSPLC and identify prognostic factors of outcome.
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High-dose aspirin consumption contributes to decreased risk for pancreatic cancer in a systematic review and meta-analysis.
Pancreas
PUBLISHED: 08-16-2014
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The aim of this study was to analyze the association between aspirin intake and its effect for chemoprevention of pancreatic cancer incidence by using a meta-analysis method.
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Egg consumption is associated with increased risk of ovarian cancer: Evidence from a meta-analysis of observational studies.
Clin Nutr
PUBLISHED: 07-23-2014
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The findings of epidemiologic studies on the association between egg consumption and ovarian cancer risk remain conflicting. The aim of this meta-analysis was to investigate whether an association exists between egg intake and ovarian cancer risk in epidemiologic studies.
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Loss of PPM1A expression enhances invasion and the epithelial-to-mesenchymal transition in bladder cancer by activating the TGF-?/Smad signaling pathway.
Oncotarget
PUBLISHED: 07-16-2014
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The transforming growth factor-? (TGF-?) signaling pathway is believed to contribute to carcinoma development by increasing cell invasiveness and metastasis and inducing the epithelial-to-mesenchymal transition (EMT). Protein phosphatase PPM1A has been reported to dephosphorylate TGF-?-activated Smad2/3, thus inhibiting the TGF-? signaling pathway. In this study, we investigated the role of PPM1A in bladder cancer. PPM1A protein expression was analyzed in 145 bladder cancer specimens. The loss of PPM1A expression was predictive of poor survival and high muscle-invasiveness. PPM1A was more commonly deficient among muscle-invasive relapse samples compared to primary tumors in twenty paired bladder cancer tissues. Functional studies indicated that blockade of PPM1A through lentivirus-mediated RNA interference significantly promoted urinary bladder cancer (BCa) cell motility, the EMT in vitro and metastasis in vivo, and these effects were dependent on the TGF-?/Smad signaling pathway. The increase in p-Smad2/3 induced by TGF-?1 correlated with the degree of PPM1A depletion in BCa cells, which resulted in an altered expression profile of TGF-?-inducible genes. The correlations between PPM1A and biomarkers related to the TGF-? signaling pathway and tumor invasion were also detected in BCa samples. These results demonstrate that loss of PPM1A is associated with the development of tumor invasion in bladder cancer patients.
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Platinum nanoparticles supported on Ca(Mg)-zeolites for efficient room-temperature alcohol oxidation under aqueous conditions.
Chem. Commun. (Camb.)
PUBLISHED: 07-13-2014
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Platinum nanoparticles supported on Ca(Mg)-ZSM-5 is an efficient, highly selective and stable catalyst for room-temperature oxidation of alcohols in water. Based on in situ EPR measurement and the radical trapping technique, we propose that the generation of ?OH radicals by cleavage of the O-O bond in the H2O2 intermediate is the rate determining step, which participated in the abstraction of H from the ?-C-H bond of alcohol molecules to produce aldehydes/ketones.
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Electronic and vibrational properties of stable isomers of (SiO)n((0,±)) (n = 2-7) clusters.
J Phys Chem A
PUBLISHED: 06-17-2014
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First-principles calculations based on density functional theory have been performed to explore the stable configurations, electronic structures, and vibrational spectra of neutral and charged silicon monoxide clusters (SiO)n((0,±)) (n = 2-7), which could be used as precursors in the synthesis of silicon nanowires. Our theoretical calculations provide new results on characteristic electron affinity, ionization potential, and vibrational spectroscopy, guiding future experiments in the synthesis of high-quality silicon nanowires. Specifically, as the number of SiO units n increases, IR spectra of (SiO)n(±) and Raman spectra of (SiO)n(-) show an evident blue shift, and Raman spectra of (SiO)n demonstrate a red shift. Moreover, most of the neutral silicon monoxide clusters have strong IR intensities and weak Raman activities, while most of the anionic counterparts have relatively weak IR intensities and strong Raman activities. Some other energetically competitive isomers of some (SiO)n((0,±)) species were also studied for comparison.
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Homocysteine Promotes Intestinal Fibrosis in Rats with Trinitrobenzene Sulfonic Acid-Induced Colitis.
Dig. Dis. Sci.
PUBLISHED: 06-10-2014
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Previous studies have revealed significantly increased levels of plasma and mucosal homocysteine (Hcy) in patients with Crohn's disease (CD); however, whether Hcy is involved in intestinal fibrosis of CD remains unclear. This study aimed to investigate the effects of Hcy on intestinal fibrosis in TNBS/ethanol-induced colitis and to elucidate its potential mechanisms.
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Multifunctional RNA Processing Protein SRm160 Induces Apoptosis and Regulates Eye and Genital Development in Drosophila.
Genetics
PUBLISHED: 06-06-2014
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SRm160 is an SR-like protein implicated in multiple steps of RNA processing and nucleocytoplasmic export. Although its biochemical functions have been extensively described, its genetic interactions and potential participation in signaling pathways remain largely unknown, despite the fact that it is highly phosphorylated in both mammalian cells and Drosophila. To begin elucidating the functions of the protein in signaling and its potential role in developmental processes, we characterized mutant and overexpression SRm160 phenotypes in Drosophila and their interactions with the locus encoding the LAMMER protein kinase, Doa. SRm160 mutations are recessive lethal, while its overexpression generates phenotypes including roughened eyes and highly disorganized internal eye structure, which are due at least in part to aberrantly high levels of apoptosis. SRm160 is required for normal somatic sex determination, since its alleles strongly enhance a subtle sex transformation phenotype induced by Doa kinase alleles. Moreover, modification of SRm160 by DOA kinase appears to be necessary for its activity, since Doa alleles suppress phenotypes induced by SRm160 overexpression in the eye and enhance those in genital discs. Modification of SRm160 may occur through direct interaction because DOA kinase phosphorylates it in vitro. Remarkably, SRm160 protein was concentrated in the nuclei of precellular embryos but was very rapidly excluded from nuclei or degraded coincident with cellularization. Also of interest, transcripts are restricted almost exclusively to the developing nervous system in mature embryos.
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The IL-8/CXCR1 axis is associated with cancer stem cell-like properties and correlates with clinical prognosis in human pancreatic cancer cases.
Sci Rep
PUBLISHED: 05-01-2014
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CXCR1, a receptor for CXCL8/IL-8, has recently been demonstrated to be associated with cancer stem cell (CSC) populations in certain types of human cancers. However, the effect of CXCR1 on CSC and its prognostic value in human pancreatic cancer remain unknown. In this study, we evaluated the expression of CXCR1 in human pancreatic duct adenocarcinoma (PDAC) and found that positive CXCR1 expression correlated with lymph node metastasis (P = 0.017) and a poor survival rate (HR, 3.748; 95% CI, 1.822 to 7.712; P < 0.001) in patients with PDAC. In addition, we identified significant positive correlations between CXCR1 and CD44 (P = 0.002) and CD133 (P = 0.017). Further functional studies confirmed that IL-8 addition increased sphere formation, CSC populations, and cell invasion of pancreatic cancer cells and that these effects could be reversed by antagonizing CXCR1 with a CXCR1-specific antibody. Therefore, our study demonstrated that the IL-8/CXCR1 axis is associated with the CSC-like properties of pancratic cancer cells and prognosis in human pancreatic cancer. This suggested a way of targeting pancreatic CSCs by disrupting IL-8/CXCR1 axis.
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Acetylation: a lysine modification with neuroprotective effects in ischemic retinal degeneration.
Exp. Eye Res.
PUBLISHED: 04-28-2014
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Neuroretinal ischemic injury contributes to several degenerative diseases in the eye and the resulting pathogenic processes involving a series of necrotic and apoptotic events. This study investigates the time and extent of changes in acetylation, and whether this influences function and survival of neuroretinal cells following injury. Studies evaluated the time course of changes in histone deacetylase (HDAC) activity, histone-H3 acetylation and caspase-3 activation levels as well as retinal morphology and function (electroretinography) following ischemia. In addition, the effect of two HDAC inhibitors, trichostatin-A and valproic acid were also investigated. In normal eyes, retinal ischemia produced a significant increase in HDAC activity within 2 h that was followed by a corresponding significant decrease in protein acetylation by 4 h. Activated caspase-3 levels were significantly elevated by 24 h. Treatment with HDAC inhibitors blocked the early decrease in protein acetylation and activation of caspase-3. Retinal immunohistochemistry demonstrated that systemic administration of trichostatin-A or valproic acid, resulted in hyperacetylation of all retinal layers after systemic treatment. In addition, HDAC inhibitors provided a significant functional and structural neuroprotection at seven days following injury relative to vehicle-treated eyes. These results provide evidence that increases in HDAC activity is an early event following retinal ischemia, and are accompanied by corresponding decreases in acetylation in advance of caspase-3 activation. In addition to preserving acetylation status, the administration of HDAC inhibitors suppressed caspase activation and provided structural and functional neuroprotection in model of ischemic retinal injury. Taken together these data provide evidence that decrease in retinal acetylation status is a central event in ischemic retinal injury, and the hyperacetylation induced by HDAC inhibition can provide acute neuroprotection.
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Impact of cerebrovascular disease mortality on life expectancy in China.
Biomed. Environ. Sci.
PUBLISHED: 04-09-2014
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To evaluate the impact of cerebrovascular disease mortality on life expectancy (LE) in China in 2010 compared with 2005, and to identify the high-risk population (age, sex, and region) where cerebrovascular disease mortality has had a major impact on LE.
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Impact of cardiovascular disease deaths on life expectancy in Chinese population.
Biomed. Environ. Sci.
PUBLISHED: 04-09-2014
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We aimed to analyze the impact of cardiovascular disease (CVD) deaths on life expectancy (LE) in Chinese population and estimate the percentage reduction in CVD mortality needed to increase LE by 1 year from the current level, a national target of health improvement.
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Reduction of unnecessary right ventricular pacing by managed ventricular pacing and search AV+ algorithms in pacemaker patients: 12-month follow-up results of a randomized study.
Europace
PUBLISHED: 04-04-2014
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The present study was to assess the reduction of right ventricular pacing (RVP) by pacemaker algorithms of Managed Ventricular Pacing (MVP) and Search AV+ (SAV+) interval over a period of 12 months.
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Biomechanical investigation of thoracolumbar spine in different postures during ejection using a combined finite element and multi-body approach.
Int J Numer Method Biomed Eng
PUBLISHED: 04-03-2014
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The aim of this study is to investigate the dynamic response of a multi-segment model of the thoracolumbar spine and determine how the sitting posture affects the response under the impact of ejection. A nonlinear finite element model of the thoracolumbar-pelvis complex (T9-S1) was developed and validated. A multi-body dynamic model of a pilot was also constructed so an ejection seat restraint system could be incorporated into the finite element model. The distribution of trunk mass on each vertebra was also considered in the model. Dynamics analysis showed that ejection impact induced obvious axial compression and anterior flexion of the spine, which may contribute to spinal injuries. Compared with a normal posture, the relaxed posture led to an increase in stress on the cortical wall, endplate, and intradiscal pressure of 43%, 10%, 13%, respectively, and accordingly increased the risk of inducing spinal injuries. Copyright © 2014 John Wiley & Sons, Ltd.
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A mechanical model of the cornea considering the crimping morphology of collagen fibrils.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 04-03-2014
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To develop a mechanical model with which to investigate the relationship between the crimping morphology of collagen fibrils and the nonlinear mechanical behavior of the cornea.
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[A meta-analysis on the association between high-density lipoprotein particle subfractions and cardiovascular disease events].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 04-01-2014
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High-density lipoprotein cholesterol (HDL-C) has cardio-protective effects. However, results from clinical trials showed that improving HDL-C levels alone did not reduce the cardiovascular disease (CVD) events and different HDL particles (HDL-P) subfractions may relate to different CVD risk. In this meta-analysis, we reviewed prospective studies reported relationships of HDL-P subfractions with CVD risk.
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Prediction of globe rupture caused by primary blast: a finite element analysis.
Comput Methods Biomech Biomed Engin
PUBLISHED: 03-26-2014
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Although a human eye comprises less than 0.1% of the frontal body surface area, injuries to the eye are found to be disproportionally common in survivors of explosions. This study aimed to introduce a Lagrangian-Eulerian coupling model to predict globe rupture resulting from primary blast effect. A finite element model of a human eye was created using Lagrangian mesh. An explosive and its surrounding air domain were modelled using Eulerian mesh. Coupling the two models allowed simulating the blast wave generation, propagation and interaction with the eye. The results showed that the peak overpressures caused by blast wave on the corneal apex are 2080, 932.1 and 487.3 kPa for the victim distances of 0.75, 1.0 and 1.25 m, respectively. Higher stress occurred at the limbus, where the peaks for the three victim distances are 25.5, 14.1 and 6.4 MPa. The overpressure threshold of globe rupture was determined as 2000 kPa in a small-scale explosion. The findings would provide insights into the mechanism of primary blast-induced ocular injuries.
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Irradiation damage determined field emission of ion irradiated carbon nanotubes.
ACS Appl Mater Interfaces
PUBLISHED: 03-20-2014
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Figuring out the underlying relationship between the field emission (FE) properties and the ion irradiation induced structural change of carbon nanotubes (CNTs) is of great importance in developing high-performance field emitters. We report here the FE properties of Si and C ion irradiated CNTs with different irradiation doses. It is found that the FE performance of the ion irradiated CNTs ameliorates before and deteriorates after an irradiation-ion-species related dose. The improved FE properties are ascribed to the increased amount of defects, while the degraded FE performance is attributed to the great shape change of CNTs. These two structural changes are further characterized by a structural damage related parameter: dpa (displacement per atom), and the FE performance of the ion irradiated CNTs is surprisingly found to be mainly dependent on the dpa. The optimal dpa for FE of the ion irradiated CNTs is ?0.60. We ascribe this to the low irradiation doses and the low substrate temperature that make the ion irradiation play a more important role in producing defects rather than element doping. Furthermore, the ion irradiated CNTs exhibit excellent FE stability, showing promising prospects in practical applications.
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Zn/Mn-MOFs with `S-shaped' packing modes.
Acta Crystallogr C Struct Chem
PUBLISHED: 03-15-2014
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Two novel polymers exhibiting metal-organic frameworks (MOFs) have been synthesized by the combination of a metal ion with a benzene-1,3,5-tricarboxylate ligand (BTC) and 1,10-phenanthroline (phen) under hydrothermal conditions. The first compound, poly[[(?4-benzene-1,3,5-tricarboxylato-?(4)O:O':O'':O''')(?-hydroxido-?(2)O:O)bis(1,10-phenanthroline-?(2)N,N')dizinc(II)] 0.32-hydrate], {[Zn2(C9H3O6)(OH)(C12H8N2)2]·0.32H2O}n, denoted Zn-MOF, forms a two-dimensional network in which a binuclear Zn2 cluster serves as a 3-connecting node; the BTC trianion also acts as a 3-connecting centre. The overall topology is that of a 6(3) net. The phen ligands serve as appendages to the network and interdigitate with phen ligands belonging to adjacent parallel sheets. The second compound, poly[[(?6-benzene-1,3,5-tricarboxylato-?(7)O(1),O(1'):O(1):O(3):O(3'):O(5):O(5'))(?3-hydroxido-?(2)O:O:O)(1,10-phenanthroline-?(2)N,N')dimanganese(II)] 1.26-hydrate], {[Mn2(C9H3O6)(OH)(C12H8N2)]·1.26H2O}n, denoted Mn-MOF, exists as a three-dimensional network in which an Mn4 cluster serves as a 6-connecting unit, while the BTC trianion again plays the role of a 3-connecting centre. The overall topology is that of the rutile net. Phen ligands act as appendages to the network and form the `S-shaped' packing mode.
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A novel vaccine against Porcine circovirus type 2 (PCV2) and Streptococcus equi ssp. zooepidemicus (SEZ) co-infection.
Vet. Microbiol.
PUBLISHED: 03-07-2014
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To develop a vaccine against Porcine circovirus type 2 (PCV2) and Streptococcus equi ssp. zooepidemicus (SEZ) co-infection, the genes of porcine IL-18, capsid protein (Cap) of PCV2 and M-like protein (SzP) of SEZ were inserted into the swinepox virus (SPV) genome by homologous recombination. The recombinant swinepox virus rSPV-ICS was verified by PCR and indirect immunofluorescence assays. To evaluate the immunogenicity of rSPV-ICS, 28 PCV2 and SEZ seronegative Bama minipigs were immunized with rSPV-ICS (n=8), commercial PCV2 vaccine and SEZ vaccine (n=8) or wild type SPV (n=8). The results showed that SzP-specific antibody and PCV2 neutralizing antibody of the rSPV-ICS immunized group increased significantly compared to the wild type SPV treated group after vaccination and increased continuously over time. The levels of IL-4 and IFN-? in the rSPV-ICS immunized group were significantly higher than the other three groups, respectively. After been co-challenged with PCV2 and SEZ, 87.5% piglets in rSPV-ICS immunized group were survived. Significant reductions in gross lung lesion score, histopathological lung lesion score, and lymph node lesion score were noticed in the rSPV-ICS immunized group compared with the wtSPV treated group. The results suggested that the recombinant rSPV-ICS provided piglets with significant protection against PCV2-SEZ co-infection; thus, it offers proof-of-principle for the development of a vaccine for the prevention of these swine diseases.
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A new reaction between common compounds: lead oxide reacts with formaldehyde.
Chem. Commun. (Camb.)
PUBLISHED: 03-07-2014
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We show here a new reaction between lead(II) oxide and formaldehyde aqueous solution, which has been overlooked all along. The special structure of the new substance (PbCH2O2) and the DFT calculations suggest a diol-mechanism, which not only informs people about the corrosive nature of HCHO toward Pb and PbO, but also leads us to discover some new reactions between a variety of vicinal diol-type molecules and PbO. The reaction is further highlighted because of its potential application in detection and treatment of formaldehyde-containing wastewaters.
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Effect of Tran on virulence through regulating metabolism and stress tolerance of Streptococcus suis serotype 2.
Microbiol. Res.
PUBLISHED: 03-05-2014
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Streptococcus suis (SS) is an important zoonotic pathogen causing a variety of life-threatening infections in pigs and humans. Tran, a novel transcriptional regulator which was identified to be an infection-related factor in S. suis serotype 2 using suppression subtractive hybridization (SSH), has been reported by our group. In this study, a tran deletion mutant was constructed to compare with the wild-type ZY05719 in some biological characteristics. It is suggested that longer chains and relatively slower growth could be observed in tran deletion mutants. In order to identify gene transcription profiles, microarray analysis was performed. It indicated that the inactivation of Tran led to 130 differentially expressed genes spread throughout the genome. Among these, 21 genes were upregulated, and 109 genes were downregulated. Most of the differentially expressed genes were involved in bacterial metabolism, such as the phosphotransferase system (PTS), and heat shock proteins. In the case of glucose scarcity, the growth characteristics of tran deletion mutants were impacted significantly, meanwhile ?tran mutant was highly sensitive to environmental stresses. Moreover, cell adherence decreased by 22.2%, and virulence in zebrafish declined to more than five times in ?tran mutants. These data demonstrate the role of Tran in regulation in S. suis serotype 2, that is affect bacterial virulence by influencing bacterial metabolism and stress tolerance of external environment.
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Triggering unfolded protein response by 2-Deoxy-D-glucose inhibits porcine epidemic diarrhea virus propagation.
Antiviral Res.
PUBLISHED: 03-05-2014
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The unfolded protein response (UPR) is cyto-protective machinery elicited towards an influx of large amount of protein synthesis in the endoplasmic reticulum (ER). Extensive studies suggest that the UPR can also be activated during virus infection. In the present studies, we first evaluated if porcine epidemic diarrhea virus (PEDV) infection activated the UPR pathways. Electron microscopy analysis demonstrated the morphology changes of ER post-PEDV infection. Western blot and real-time PCR identified the differences of UPR genes in response to PEDV infection. The results suggested that PEDV infection induced UPR in Vero cells. Meanwhile, we silenced the expression of PKR-like ER kinase (PERK) by shRNA, we found that the knockdown of PERK increased virus loads in the cells, which was consistent with the result on 4-phenylbutyrate (4-PBA) treatment. We next determined whether 2-Deoxy-d-glucose (2-DG), an ER stress inducer, possessed antiviral activity against PEDV infection. Plaque formation assay, RT-PCR and Western blot analysis suggested that 2-DG might inhibit virus infection by affecting viral protein translation during the early stage of virus infection. Interestingly, we also found that 2-DG treatment could affect virus assembly, which is similar to previous studies on influenza virus. All these results support the therapeutic potential of using 2-DG or glucose/mannose analogs to induce the UPR to block virus replication.
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MiR-29b inhibits collagen maturation in hepatic stellate cells through down-regulating the expression of HSP47 and lysyl oxidase.
Biochem. Biophys. Res. Commun.
PUBLISHED: 02-27-2014
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Altered expression of miR-29b is implicated in the pathogenesis and progression of liver fibrosis. We and others previously demonstrated that miR-29b down-regulates the expression of several extracellular-matrix (ECM) genes including Col 1A1, Col 3A1 and Elastin via directly targeting their 3'-UTRs. However, whether or not miR-29b plays a role in the post-translational regulation of ECM biosynthesis has not been reported. Heat shock protein 47 (HSP47) and lysyl oxidase (LOX) are known to be essential for ECM maturation. In this study we have demonstrated that expression of HSP47 and LOX was significantly up-regulated in culture-activated primary rat hepatic stellate cells (HSCs), TGF-? stimulated LX-2 cells and liver tissue of CCl4-treated mice, which was accompanied by a decrease of miR-29b level. In addition, over-expression of miR-29b in LX-2 cells resulted in significant inhibition on HSP47 and LOX expression. Mechanistically, miR-29b inhibited the expression of a reporter gene that contains the respective full-length 3'-UTR from HSP47 and LOX gene, and this inhibitory effect was abolished by the deletion of a putative miR-29b targeting sequence from the 3'-UTRs. Transfection of LX-2 cells with miR-29b led to abnormal collagen structure as shown by electron-microscopy, presumably through down-regulation of the expression of molecules involved in ECM maturation including HSP47 and LOX. These results demonstrated that miR-29b is involved in regulating the post-translational processing of ECM and fibril formation.
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An ordered, extra-large mesoporous ceramic acid with strong Brönsted acid sites and excellent thermal/hydrothermal stability.
Chem. Commun. (Camb.)
PUBLISHED: 02-19-2014
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A thermal and hydrothermal stable mesoporous ceramic acid (mCA) was synthesized by uniform coating of a WZrO(x) layer onto the internal surface of extra-large mesoporous silica (EP-FDU-12). Its ordered mesoporous structure and strong Brönsted acid sites display excellent thermal (1000 °C, air, 5 h) and hydrothermal (water steam, 300 °C, 24 h) stability.
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Biofilm formation of Streptococcus equi ssp. zooepidemicus and comparative proteomic analysis of biofilm and planktonic cells.
Curr. Microbiol.
PUBLISHED: 02-08-2014
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Streptococcus equi ssp. zooepidemicus (SEZ) is responsible for a wide variety of infections in many species, including pigs, horses and humans. Biofilm formation is essential for pathogenesis, and the ability to resist antibiotic treatment results in difficult-to-treat and persistent infections. However, the ability of SEZ to form biofilms is unclear. Furthermore, the mechanisms underlying SEZ biofilm formation and their attributes are poorly understood. In this study, scanning electron microscopy (SEM) demonstrated that SEZ strain ATCC35246 formed biofilms comprising a thick, heterogeneous layer with clumps on the coverslips when incubated for 24 h. In addition, we used a two-dimensional gel electrophoresis (2-DE) based approach to characterize differentially expressed protein in SEZ biofilms compared with their planktonic counterparts. The results revealed the existence of 24 protein spots of varying intensities, 13 of which were upregulated and 11 were downregulated in the SEZ biofilm compared with the planktonic controls. Most of proteins expressed during biofilm formation were associated with metabolism, adhesion, and stress conditions. These observations contribute to our understanding of the SEZ biofilm lifestyle, which may lead to more effective measures to control persistent SEZ infections.
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Tumor suppressor microRNA-34a inhibits cell proliferation by targeting Notch1 in renal cell carcinoma.
Oncol Lett
PUBLISHED: 01-24-2014
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MicroRNA-34a (miR-34a) is a tumor suppressive microRNA, which induces G1 arrest, apoptosis and senescence by repressing the expression of multiple oncogenes. This study aimed to investigate the biological function and molecular mechanisms of miR-34a in human renal cell carcinoma (RCC) cells. Quantitative polymerase chain reaction (qPCR) revealed that miR-34a expression was significantly downregulated in eight of the 10 (80%) RCC tissues compared with adjacent normal tissues. In RCC cell lines, several other target genes of miR-34a were dysregulated at the mRNA level when the expression of miR-34a was elevated. In addition, western blot analysis and qPCR revealed that forced expression of miR-34a downregulated the expression of Notch1 at the protein and mRNA level. The Cell Counting Kit-8 identified that transient forced expression of miR-34a inhibited cell growth and resulted in cell cycle arrest, which was evaluated by flow cytometry. Our data demonstrated that miR-34a inhibits cell proliferation by downregulating Notch1 in RCC cell lines.
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The complete mitochondrial genome of Java warty pig (Sus verrucosus).
Mitochondrial DNA
PUBLISHED: 01-21-2014
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Abstract In the present study, the complete mitochondrial genome sequence of the Java warty pig was reported for the first time. The total length of the mitogenome was 16,479?bp. It contained the typical structure, including 2 ribosomal RNA genes, 13 protein-coding genes, 22 transfer RNA genes and 1 non-coding control region (D-loop region) as that of most other pigs. The overall composition of the mitogenome was estimated to be 34.9% for A, 26.1% for T, 26.0% for C and 13.0% for G showing an A-T (61.0%)-rich feature. The mitochondrial genome analyzed here will provide new genetic resource to uncover pigs' evolution.
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A dual-targeting liposome conjugated with transferrin and arginine-glycine-aspartic acid peptide for glioma-targeting therapy.
Oncol Lett
PUBLISHED: 01-15-2014
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The treatment of a brain glioma remains one of the most difficult challenges in oncology. In the present study a delivery system was developed for targeted drug delivery across the blood-brain barrier (BBB) to the brain cancer cells. A cyclic arginine-glycine-aspartic acid (RGD) peptide and transferrin (TF) were utilized as targeting ligands. Cyclic RGD peptides are specific targeting ligands of cancer cells and TFs are ligands that specifically target the BBB and cancer cells. Liposome (LP) was used to conjugate the cyclic RGD and TFs to establish the brain glioma cascade delivery system (RGD/TF-LP). The LPs were prepared by the thin film hydration method and physicochemical characterization was conducted. In vitro cell uptake and three-dimensional tumor spheroid penetration studies demonstrated that the system could target endothelial and tumor cells, as well as penetrate the tumor cells to reach the core of the tumor spheroids. The results of the in vivo imaging further demonstrated that the RGD/TF-LP provided the highest brain distribution. As a result, the paclitaxel-loaded RGD/TF-LP presents the best antiproliferative activity against C6 cells and tumor spheroids. In conclusion, the RGD/TF-LP may precisely target brain glioma, which may be valuable for glioma imaging and therapy.
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Effects of laparoscopic adjustable gastric banding on weight loss, metabolism, and obesity-related comorbidities: 5-year results in China.
Obes Surg
PUBLISHED: 01-10-2014
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Despite some reports about the long-term metabolic outcomes after laparoscopic adjustable gastric banding (LAGB) in the Western populations, there are few reports on the Asian population whose body size and fat distribution are different. Therefore, this study was conducted to evaluate the medium-term effects of LAGB on weight loss and metabolic outcomes of obese patients with different body mass index (BMI) in China.
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Effect of acute, slightly increased intra-abdominal pressure on intestinal permeability and oxidative stress in a rat model.
PLoS ONE
PUBLISHED: 01-01-2014
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Intra-abdominal hypertension (IAH) is known as a common, serious complication in critically ill patients. Bacterial translocation and permeability changes are considered the pathophysiological bases for IAH-induced enterogenic endotoxemia and subsequent multiorgan failure. Nevertheless, the effects of slightly elevated intra-abdominal pressures (IAPs) on the intestinal mucosa and the associated mechanisms remain unclear.
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Systematic significance of leaf epidermal features in holcoglossum (orchidaceae).
PLoS ONE
PUBLISHED: 01-01-2014
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Determining the generic delimitations within Aeridinae has been a significant issue in the taxonomy of Orchidaceae, and Holcoglossum is a typical case. We investigated the phylogenetic utility of the morphological traits of leaf epidermis in the taxonomy of Holcoglossum s.l. by using light and scanning electron microscopy to analyze 38 samples representing 12 species of Holcoglossum, with five species from five closely related genera, such as Ascocentrum, Luisia, Papilionanthe, Rhynchostylis and Vanda. Our results indicated that Holcoglossum can be distinguished from the related genera based on cuticular wax characteristics, and the inclusion of Holcoglossum himalaicum in Holcoglossum is supported by the epidermis characteristics found by LM and SEM. The percentage of the tetracytic, brachyparacytic, and laterocytic stomata types as well as the stomata index and certain combinations of special wax types support infrageneric clades and phylogenetic relationships that have been inferred from molecular data. Laterocytic and polarcytic stomata are perhaps ecological adaptations to the strong winds and ample rains in the alpine region of the Hengduanshan Mountains.
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Comparison of leaf proteomes of cassava (Manihot esculenta Crantz) cultivar NZ199 diploid and autotetraploid genotypes.
PLoS ONE
PUBLISHED: 01-01-2014
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Cassava polyploid breeding has drastically improved our knowledge on increasing root yield and its significant tolerance to stresses. In polyploid cassava plants, increases in DNA content highly affect cell volumes and anatomical structures. However, the mechanism of this effect is poorly understood. The purpose of the present study was to compare and validate the changes between cassava cultivar NZ199 diploid and autotetraploid at proteomic levels. The results showed that leaf proteome of cassava cultivar NZ199 diploid was clearly differentiated from its autotetraploid genotype using 2-DE combined MS technique. Sixty-five differential protein spots were seen in 2-DE image of autotetraploid genotype in comparison with that of diploid. Fifty-two proteins were identified by MALDI-TOF-MS/MS, of which 47 were up-regulated and 5 were down-regulated in autotetraploid genotype compared with diploid genotype. The classified functions of 32 up-regulated proteins were associated with photosynthesis, defense system, hydrocyanic acid (HCN) metabolism, protein biosynthesis, chaperones, amino acid metabolism and signal transduction. The remarkable variation in photosynthetic activity, HCN content and resistance to salt stress between diploid and autotetraploid genotypes is closely linked with expression levels of proteomic profiles. The analysis of protein interaction networks indicated there are direct interactions between the 15 up-regulation proteins involved in the pathways described above. This work provides an insight into understanding the protein regulation mechanism of cassava polyploid genotype, and gives a clue to improve cassava polyploidy breeding in increasing photosynthesis and resistance efficiencies.
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[Clinical significance of glucocorticoid induction test in Chinese childhood acute lymphoblastic leukemia].
Zhonghua Er Ke Za Zhi
PUBLISHED: 11-26-2013
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Acute lymphoblastic leukemia (ALL) is the most common childhood cancer, while glucocorticoid (GC) is a critical component in multi-agent chemotherapy protocols currently used for the treatment of ALL. The purpose of this study was to investigate the relationship between the glucocorticoid induction test and the clinical features and the prognosis of Chinese childhood ALL.
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Electrospun hierarchical TiO2 nanorods with high porosity for efficient dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 09-05-2013
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Ultraporous anatase TiO2 nanorods with a composite structure of mesopores and macropores fabricated via a simple microemulsion electrospinning approach were first used as photoanode materials for high-efficiency dye-sensitized solar cells (DSSCs). The special multiscale porous structure was formed by using low-cost paraffin oil microemulsion droplets as the soft template, which can not only provide enhanced adsorption sites for dye molecules but also facilitate the electrolyte diffusion. The morphology, porosity, and photovoltaic and electron dynamic characteristics of the porous TiO2 nanorod based DSSCs were investigated in detail by scanning electron microscopy (SEM), N2 sorption measurements, current density-voltage (J-V) curves, UV-vis diffuse reflectance spectra, electrochemical impedance spectroscopy (EIS), intensity modulated photocurrent/photovoltage spectroscopy (IMPS/IMVS), and open-circuit voltage decay (OCVD) measurements. The results revealed that, although fewer amounts of dyes were anchored on the porous TiO2 nanorod films, they exhibited stronger light scattering ability, fast electrolyte diffusion, and extended electron lifetime compared to the commercial P25 nanoparticles. A power conversion efficiency of 6.07% was obtained for the porous TiO2 nanorod based DSSCs. Moreover, this value can be further improved to 8.53% when bilayer structured photoanode with porous TiO2 nanorods acting as the light scattering layer was constructed. This study demonstrated that the porous TiO2 nanorods can work as promising photoanode materials for DSSCs.
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Critical role of AKT protein in myeloma-induced osteoclast formation and osteolysis.
J. Biol. Chem.
PUBLISHED: 09-04-2013
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Abnormal osteoclast formation and osteolysis are the hallmarks of multiple myeloma (MM) bone disease, yet the underlying molecular mechanisms are incompletely understood. Here, we show that the AKT pathway was up-regulated in primary bone marrow monocytes (BMM) from patients with MM, which resulted in sustained high expression of the receptor activator of NF-?B (RANK) in osteoclast precursors. The up-regulation of RANK expression and osteoclast formation in the MM BMM cultures was blocked by AKT inhibition. Conditioned media from MM cell cultures activated AKT and increased RANK expression and osteoclast formation in BMM cultures. Inhibiting AKT in cultured MM cells decreased their growth and ability to promote osteoclast formation. Of clinical significance, systemic administration of the AKT inhibitor LY294002 blocked the formation of tumor tissues in the bone marrow cavity and essentially abolished the MM-induced osteoclast formation and osteolysis in SCID mice. The level of activating transcription factor 4 (ATF4) protein was up-regulated in the BMM cultures from multiple myeloma patients. Adenoviral overexpression of ATF4 activated RANK expression in osteoclast precursors. These results demonstrate a new role of AKT in the MM promotion of osteoclast formation and bone osteolysis through, at least in part, the ATF4-dependent up-regulation of RANK expression in osteoclast precursors.
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Hepatitis E virus genotype 4, Nanjing, China, 2001-2011.
Emerging Infect. Dis.
PUBLISHED: 08-23-2013
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During 2001-2011, hepatitis E virus (HEV) was found in the blood of patients in Nanjing, China. All HEV-positive patients had virus genotype 4; subgenotype 4a was predominant. The effective population of HEV in Nanjing increased in ?1980 and continued until ?2003 when it plateaued.
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[Cnb1 involved in cytokinesis in Schizosaccharomyces pombe].
Yi Chuan
PUBLISHED: 08-20-2013
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Serine/Threonine-specific calcineurin (CN) is highly conserved in eukaryotes, which plays an important role in transcriptional regulation. In Schizosaccharomyces pombe, CN exists as a heterodimer composed by catalytic subunit Ppb1 and regulatory subunit Cnb1. Deletion of cnb1+ reduced the growth rate of cells, and caused a chained phenotype, and had delay in cytokinesis. In cytokinesis, Cnb1 could form CN complex with Ppb1 and could colocalize and constrict with the contractile ring at division plane. Tubulin could cross the septum in cnb1? strain, suggesting that the septum is not fully matured. These results suggest Cnb1 might be involved in maturation of septum. The signals of septins in cnb1? strain were also analyzed. Septins include Spn1, Spn2, Spn3, and Spn4. Septins help to guide hydrolytic enzymes for septum degrada-tion. Eighty percent of cnb1? cells lacked the signals of Spn2 or Spn3 at septum, and twenty percent of cnb1? cells lacked the signals of Spn1 or Spn4 at septum. The reduction of the septin signals was not due to impaired transcription of septins, since the protein levels of septins in the cnb1? cells were not decreased. These results imply that Cnb1 might regulate the stability of septin ring in a transcription-independent manner. In general, our study showed that Cnb1 contributes to the maturation of septum and the stability of septin ring and is important in the cytokinesis.
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[Progress of research on microRNAs of parasites].
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 07-31-2013
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microRNAs (miRNAs) are small molecules of non-coding RNA, a class size of about 21-25 nt widespread in eukaryotes, resulting from single-stranded RNA precursors with the size of 70-90 bases of a hairpin structure generated after dicer enzyme processing. They play an important role in eukaryotic gene regulation, widely involved in cell proliferation, differentiation, development, metabolism, apoptosis and other physiological activities. miRNA extensively involved in the physiological and metabolic processes of the parasite development process, but the key miRNA relevant to parasite invasion of a host still lacks reports. This paper summarizes the miRNA analytical methods and the progress on its researches in parasitology.
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[Prevalence and risk factors of atherosclerotic renal artery stenosis].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 07-18-2013
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To explore the prevalence and risk factors of atherosclerotic renal artery stenosis (ARAS) in patients undergoing coronary angiography.
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[An evaluation of the impact of cerebrovascular disease deaths on life expectancy in China].
Zhonghua Nei Ke Za Zhi
PUBLISHED: 07-17-2013
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To evaluate the impact of cerebrovascular death on the life expectancy of Chinese residents in recent years and explore the difference in the subgroups.
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Identification of differentially-expressed genes potentially implicated in drought response in pitaya (Hylocereus undatus) by suppression subtractive hybridization and cDNA microarray analysis.
Gene
PUBLISHED: 07-11-2013
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Drought is one of the most severe threats to the growth, development and yield of plant. In order to unravel the molecular basis underlying the high tolerance of pitaya (Hylocereus undatus) to drought stress, suppression subtractive hybridization (SSH) and cDNA microarray approaches were firstly combined to identify the potential important or novel genes involved in the plant responses to drought stress. The forward (drought over drought-free) and reverse (drought-free over drought) suppression subtractive cDNA libraries were constructed using in vitro shoots of cultivar Zihonglong exposed to drought stress and drought-free (control). A total of 2112 clones, among which half were from either forward or reverse SSH library, were randomly picked up to construct a pitaya cDNA microarray. Microarray analysis was carried out to verify the expression fluctuations of this set of clones upon drought treatment compared with the controls. A total of 309 expressed sequence tags (ESTs), 153 from forward library and 156 from reverse library, were obtained, and 138 unique ESTs were identified after sequencing by clustering and blast analyses, which included genes that had been previously reported as responsive to water stress as well as some functionally unknown genes. Thirty six genes were mapped to 47 KEGG pathways, including carbohydrate metabolism, lipid metabolism, energy metabolism, nucleotide metabolism, and amino acid metabolism of pitaya. Expression analysis of the selected ESTs by reverse transcriptase polymerase chain reaction (RT-PCR) corroborated the results of differential screening. Moreover, time-course expression patterns of these selected ESTs further confirmed that they were closely responsive to drought treatment. Among the differentially expressed genes (DEGs), many are related to stress tolerances including drought tolerance. Thereby, the mechanism of drought tolerance of this pitaya genotype is a very complex physiological and biochemical process, in which multiple metabolism pathways and many genes were implicated. The data gained herein provide an insight into the mechanism underlying the drought stress tolerance of pitaya, as well as may facilitate the screening of candidate genes for drought tolerance.
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[Effects of imidazolium chloride ionic liquids on the acute toxicity and weight of earthworm].
Huan Jing Ke Xue
PUBLISHED: 06-27-2013
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Standard contact filter paper test of OECD and artificial soil test were used to study the acute lethal effect of three imidazolium chloride ionic liquids, 1-butyl- 3-methylimidazolium chloride ([Bmim] Cl), 1-hexyl- 3-methylimidazolium chloride ([Hmim] Cl), and 1-octyl- 3-methylimidazolium chloride ([Omim] Cl) on earthworm (Eisenia fetida), and the weight of the earthworms was measured after subtle exposure. The 24 h-LC50 values of [Bmim] Cl, [Hmim] Cl and [Omim] Cl using the contact filter paper method were 109.60, 50.38 and 7.94 microg x cm(-2), respectively. The 48 h-LC50 values were 98.52, 39.14 and 3.61 microg x cm(-2), respectively. Using the artificial soil method, the 7 d-LC50 values of [Bmim] Cl, [Hmim] Cl and [Omim] Cl were 447.78, 245.56 and 180.51 mg x kg(-1), respectively, and the 14 d-LC50 values were 288.42, 179.75, 150.35 mg x kg(-1), respectively. There were differences in poisoning symptoms of the three ionic liquids on earthworms. The growth of Eisenia fetida was inhibited and declined with increasing ionic liquid concentration. The toxicity of ionic liquids on Eisenia fetida increased with the length of carbon chain.
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TLR4 Signaling augments monocyte chemotaxis by regulating G protein-coupled receptor kinase 2 translocation.
J. Immunol.
PUBLISHED: 06-14-2013
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Monocytes are critical effector cells of the innate immune system that protect the host by migrating to inflammatory sites, differentiating to macrophages and dendritic cells, eliciting immune responses, and killing pathogenic microbes. MCP-1, also known as CCL2, plays an important role in monocyte activation and migration. The chemotactic function of MCP-1 is mediated by binding to the CCR2 receptor, a member of the G protein-coupled receptor (GPCR) family. Desensitization of GPCR chemokine receptors is an important regulator of the intensity and duration of chemokine stimulation. GPCR kinases (GRKs) induce GPCR phosphorylation, and this leads to GPCR desensitization. Regulation of subcellular localization of GRKs is considered an important early regulatory mechanism of GRK function and subsequent GPCR desensitization. Chemokines and LPS are both present during Gram-negative bacterial infection, and LPS often synergistically exaggerates leukocyte migration in response to chemokines. In this study, we investigated the role and mechanism of LPS-TLR4 signaling on the regulation of monocyte chemotaxis. We demonstrate that LPS augments MCP-1-induced monocyte migration. We also show that LPS, through p38 MAPK signaling, induces phosphorylation of GRK2 at serine 670, which, in turn, suppresses GRK2 translocation to the membrane, thereby preventing GRK2-initiated internalization and desensitization of CCR2 in response to MCP-1. This results in enhanced monocyte migration. These findings reveal a novel function for TLR4 signaling in promoting innate immune cell migration.
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Microfluidic chip-based analytical system for rapid screening of photocatalysts.
Talanta
PUBLISHED: 06-06-2013
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A simple and efficient microfluidic chip-based analytical system for rapid screening of photocatalysts was developed. The catalyst screening system consisted of a microchip with multiple channels for parallel reactions, a UV light source, and a CCD camera-based photometric detection system for monitoring the photocatalytic reaction. A novel microfluidic introduction method for loading particle samples into chip microchannels was established using dry sample powders and wedge-structure channel design. With this method, multiple different photocatalyst samples could be quickly introduced into the microchip with good reproducibility without the need of additional pumps or valves. We applied the present system in the rapid screening of doping TiO2 photocatalysts in terms of their activity for methylene blue (MB) degradation under UV light irradiation. Ten parallel photocatalyst screening reactions were achieved within 15 min in the multi-channel chip. We also examined nine element doped TiO2 materials to investigate the doping effects of different elements on TiO2. Compared with conventional systems, the photocatalyst consumption (0.1mg) in the present system was significantly reduced at least 100 times. High reaction rate in chip microreactors was obtained with an increase of two orders of magnitude over bulk reactors. The miniaturization of the photocatalytic reaction on the microchip significantly improves the reaction rates, reduces the sample and reagent consumptions, and increases the throughput of screening for multiple catalyst samples in parallel. The present work provides a novel application for microfluidic chip-based analytical systems, as well as a rapid, highly-efficient and low-consumption method for screening of photocatalysts.
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Inhibition of HDAC2 protects the retina from ischemic injury.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 05-23-2013
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Protein acetylation is an essential mechanism in regulating transcriptional and inflammatory events. Studies have shown that nonselective histone deacetylase (HDAC) inhibitors can protect the retina from ischemic injury in rats. However, the role of specific HDAC isoforms in retinal degenerative processes remains obscure. The purpose of this study was to investigate the role of HDAC2 isoform in a mouse model of ischemic retinal injury.
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Anti-fibrotic effect of thymoquinone on hepatic stellate cells.
Phytomedicine
PUBLISHED: 05-06-2013
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Hepatic stellate cells (HSCs) are the major cell type involved in the production of extracellular matrix in liver. After liver injury, HSCs undergo transdifferentiation process from quiescent state to activated state, which plays an important role in liver fibrosis. Previous studies have shown that thymoquinone (TQ) might have protective effect against liver fibrosis in animal models; however, the underlying mechanism of action is not fully understood. The aim of this study is to examine whether TQ has any direct effect on HSCs. Our results showed that pretreatment of mice with TQ has protective effect against CCl4-induced liver injury compared to control group (untreated), which is consistent with previous studies. Moreover, our in vivo study showed that COL1A1 and ?-SMA mRNA levels were significantly downregulated by TQ treatment. Similarly, in vitro study confirmed that TQ downregulated COL1A1, COL3A1 and ?-SMA mRNA levels in activated rat HSCs and LX2 cells, an immortalized human hepatic stellate cell line. Pretreatment with TQ also inhibited the LPS-induced proinflammatory response in LX2 cells as demonstrated by reduced mRNA expression of IL-6 and MCP-1. Mechanistically, inactivation of NF-?B pathway is likely to play a role in the TQ-mediated inhibition of proinflammatory response in HSCs. Finally, we have shown that TQ inhibited the culture-triggered transdifferentiation of freshly isolated rat HSCs as shown by significant downregulation of mRNA expression of several fibrosis-related genes. In conclusion, our study suggests that TQ has a direct effect on HSCs, which may contribute to its overall antifibrotic effect.
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High-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine and carboplatin chemotherapy in locally advanced non-small-cell lung cancer: a feasibility study.
Radiat Oncol
PUBLISHED: 05-05-2013
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Increasing the radiotherapy dose can result in improved local control for non-small-cell lung cancer (NSCLC) and can thereby improve survival. Accelerated hypofractionated radiotherapy can expose tumors to a high dose of radiation in a short period of time, but the optimal treatment regimen remains unclear. The purpose of this study was to evaluate the feasibility of utilizing high-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine (NVB) and carboplatin (CBP) chemotherapy for the treatment of local advanced NSCLC.
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The preliminary exploration of 64-slice volume computed tomography in the accurate measurement of pleural effusion.
Acta Radiol
PUBLISHED: 04-30-2013
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Using computed tomography (CT) to rapidly and accurately quantify pleural effusion volume benefits medical and scientific research. However, the precise volume of pleural effusions still involves many challenges and currently does not have a recognized accurate measuring.
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Ordered, extra-large mesopores with highly loaded gold nanoparticles: a new sintering- and coking-resistant catalyst system.
Chem. Commun. (Camb.)
PUBLISHED: 04-26-2013
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Ordered, extra-large mesopores with highly loaded gold nanoparticles (AuNPs) exhibits unique sintering- and coking-resistant properties in gas-phase, cyclohexanol selective aerobic oxidation.
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Overexpression of RING box protein-1 (RBX1) associated with poor prognosis of non-muscle-invasive bladder transitional cell carcinoma.
J Surg Oncol
PUBLISHED: 04-23-2013
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RING box protein-1 (RBX1) is a key subunit of the ubiquitin E3 ligase Skp1/Cullin1/Rbx1/F-box protein complex. Altered expression RBX1 is shown to associate with tumorigenesis and tumor progression. This study detected RBX1 expression for association with clinical significance (such as clinicopathological data and survival of the patients) in non-muscle-invasive bladder transitional cell carcinoma (NMIBC).
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Caspase 1 activation is protective against hepatocyte cell death by up-regulating beclin 1 protein and mitochondrial autophagy in the setting of redox stress.
J. Biol. Chem.
PUBLISHED: 04-15-2013
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Caspase 1 activation can be induced by oxidative stress, which leads to the release of the proinflammatory cytokines IL1? and IL18 in myeloid cells and a potentially damaging inflammatory response. However, little is known about the role of caspase 1 in non-immune cells, such as hepatocytes, that express and activate the inflammasome but do not produce a significant amount of IL1?/IL18. Here we demonstrate that caspase 1 activation protects against cell death after redox stress induced by hypoxia/reoxygenation in hepatocytes. Mechanistically, we show that caspase 1 reduces mitochondrial respiration and reactive oxygen species by increasing mitochondrial autophagy and subsequent clearance of mitochondria in hepatocytes after hypoxia/reoxygenation. Caspase 1 increases autophagic flux through up-regulating autophagy initiator beclin 1 during redox stress and is an important cell survival factor in hepatocytes. We find that during hemorrhagic shock with resuscitation, an in vivo mouse model associated with severe hepatic redox stress, caspase 1 activation is also protective against liver injury and excessive oxidative stress through the up-regulation of beclin 1. Our findings suggest an alternative role for caspase 1 activation in promoting adaptive responses to oxidative stress and, more specifically, in limiting reactive oxygen species production and damage in cells and tissues where IL1?/IL18 are not highly expressed.
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Inhibitory deficit in semantic conflict in obsessive-compulsive disorder: an event-related potential study.
Neurosci. Lett.
PUBLISHED: 04-12-2013
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The present study examines the inhibitory function of patients with obsessive-compulsive disorder (OCD) involved in semantic conflict using event-related potentials (ERPs). EPRs were recorded in a group of 18 medicine-free OCD patients and 18 normal controls using a modified Stroop paradigm in which the participants were asked to make a judgment of congruent or incongruent stimuli. The reaction time to color-word incongruent stimuli in the OCD group was significantly longer than the reaction time to congruent stimuli. In the OCD group, a significant negativity shift was discovered in P350 amplitude and N450 amplitude in response to incongruent stimuli, a shift not present in the control group. The amplitude of difference waveform was significantly higher for OCD than for control subjects. The findings probably revealed an inhibitory deficit in patients with OCD when performing semantic conflict tasks. The results suggest that this type of inhibitory deficit may be the cause of increased Stroop effects in patients with OCD, and one of contributors to the pathophysiology of OCD.
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Hemorrhagic shock augments Nlrp3 inflammasome activation in the lung through impaired pyrin induction.
J. Immunol.
PUBLISHED: 04-12-2013
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Hemorrhagic shock (HS) promotes the development of systemic inflammatory response syndrome and organ injury by activating and priming the innate immune system for an exaggerated inflammatory response through, as of yet, unclear mechanisms. IL-1? also plays an important role in the development of post-HS systemic inflammatory response syndrome and active IL-1? production is tightly controlled by the inflammasome. Pyrin, a protein of 781 aa with pyrin domain at the N-terminal, negatively regulates inflammasome activation through interaction with nucleotide-binding oligomerization domain-like receptor protein (NLRP). Expression of pyrin can be induced by LPS and cytokines, and IL-10 is a known potent inducer of pyrin expression in macrophages. In the current study, we tested the hypothesis that HS downregulates IL-10 and therefore decreases pyrin expression to promote inflammasome activation and subsequent IL-1? processing and secretion in the lungs. Our results show that LPS, while activating Nlrp3 inflammasome in the lungs, also induced pyrin expression, which in turn suppressed inflammasome activation. More importantly, LPS-mediated upregulation of IL-10 enhanced pyrin expression, which serves, particularly in later phases, as a potent negative-feedback mechanism regulating inflammasome activation. However, HS-mediated suppression of IL-10 expression in alveolar macrophages attenuated the upregulation of pyrin in alveolar macrophages and lung endothelial cells and thereby significantly enhanced inflammasome activation and IL-1? secretion in the lungs. This study demonstrates a novel mechanism by which HS suppresses negative-feedback regulation of Nlrp3 inflammasome to enhance IL-1? secretion in response to subsequent LPS challenge and so primes for inflammation.
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ATF4 promotes bone angiogenesis by increasing VEGF expression and release in the bone environment.
J. Bone Miner. Res.
PUBLISHED: 03-18-2013
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Activating transcription factor 4 (ATF4) is a critical transcription factor for bone remodeling; however, its role in bone angiogenesis has not been established. Here we show that ablation of the Atf4 gene expression in mice severely impaired skeletal vasculature and reduced microvascular density of the bone associated with dramatically decreased expression of hypoxia-inducible factor 1? (HIF-1?) and vascular endothelial growth factor (VEGF) in osteoblasts located on bone surfaces. Results from in vivo studies revealed that hypoxia/reoxygenation induction of HIF-1? and VEGF expression leading to bone angiogenesis, a key adaptive response to hypoxic conditions, was severely compromised in mice lacking the Atf4 gene. Loss of ATF4 completely prevented endothelial sprouting from embryonic metatarsals, which was restored by addition of recombinant human VEGF protein. In vitro studies revealed that ATF4 promotion of HIF-1? and VEGF expression in osteoblasts was highly dependent upon the presence of hypoxia. ATF4 interacted with HIF-1? in hypoxic osteoblasts, and loss of ATF4 increased HIF-1? ubiquitination and reduced its protein stability without affecting HIF-1? mRNA stability and protein translation. Loss of ATF4 increased the binding of HIF-1? to prolyl hydroxylases, the enzymes that hydroxylate HIF-1a protein and promote its proteasomal degradation via the pVHL pathway. Furthermore, parathyroid hormone-related protein (PTHrP) and receptor activator of NF-?B ligand (RANKL), both well-known activators of osteoclasts, increased release of VEGF from the bone matrix and promoted angiogenesis through the protein kinase C- and ATF4-dependent activation of osteoclast differentiation and bone resorption. Thus, ATF4 is a new key regulator of the HIF/VEGF axis in osteoblasts in response to hypoxia and of VEGF release from bone matrix, two critical steps for bone angiogenesis.
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Splicing proofreading at 5 splice sites by ATPase Prp28p.
Nucleic Acids Res.
PUBLISHED: 03-05-2013
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Fidelity and efficiency of pre-mRNA splicing are critical for generating functional mRNAs, but how such accuracy in 5 splice site (SS) selection is attained is not fully clear. Through a series of yeast genetic screens, we isolated alleles of prp28 that improve splicing of suboptimal 5SS substrates, demonstrating that WT-Prp28p proofreads, and consequently rejects, poor 5SS. Prp28p is thought to facilitate the disruption of 5SS-U1 snRNA pairing to allow for 5SS-U6 snRNA pairing in the catalytic spliceosome; unexpectedly, 5SS proofreading by Prp28p is dependent on competition with the stability of the 5SS:U6 duplex, but not the 5SS:U1 duplex. E404K, the strongest prp28 allele containing a mutation located in the linker region between adenosine triphosphatase (ATPase) subdomains, exhibited lower RNA-binding activity and enhanced splicing of suboptimal substrates before first-step catalysis, suggesting that decreased Prp28p activity allows longer time for suboptimal 5SS substrates to pair with U6 snRNA and thereby reduces splicing fidelity. Residue E404 is critical for providing high splicing activity, demonstrated here in both yeast and Drosophila cells. Thus, the subdomain linker in Prp28p plays important roles both in splicing efficiency across species and in proofreading of 5SS.
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A novel molecularly imprinted polymer of the specific ionic liquid monomer for selective separation of synephrine from methanol-water media.
Food Chem
PUBLISHED: 02-04-2013
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A novel molecularly imprinted polymer (MIP) using the specific ionic liquid (i.e. 1-vinyl-3-carboxymethylimidazolium bromide, 1-vinyl-3-carboxyethylimidazolium bromide, 1-viny-3-carboxybutylimidazolium bromide, or 1-vinyl-3-carboxypentylimidazolium bromide) as functional monomer was prepared via precipitation polymerization, which can be used to selectively separate synephrine (SYN) from methanol-water media. Ionic liquids are facile to be designed with varying the cation or anion, which enables the specific ionic liquid to be effectively designed to be a functional monomer for the preparation of MIP. The MIP showed a good selectivity and high adsorption capacity for SYN in methanol-water media. The adsorption process could be described by the pseudo-first-order model, which meant that the adsorption kinetics described a diffusion-controlled process. The equilibrium data fitted well to the Freundlich model, indicating multilayer adsorption. Finally, the MIP were successfully applied as sorbent to selectively enrich and separate SYN from the extracts of Aurantii Fructus Immaturus with a relatively high recovery (80-90%).
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Graft-versus-host disease is enhanced by selective CD73 blockade in mice.
PLoS ONE
PUBLISHED: 02-04-2013
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CD73 functions as an ecto-5-nucleotidase to produce extracellular adenosine that has anti-inflammatory and immunosuppressive activity. We here demonstrate that CD73 helps control graft-versus-host disease (GVHD) in mouse models. Survival of wild-type (WT) recipients of either allogeneic donor naïve CD73 knock-out (KO) or WT T cells was similar suggesting that donor naïve T cell CD73 did not contribute to GVHD. By contrast, donor CD73 KO CD4(+)CD25(+) regulatory T cells (Treg) had significantly impaired ability to mitigate GVHD mortality compared to WT Treg, suggesting that CD73 on Treg is critical for GVHD protection. However, compared to donor CD73, recipient CD73 is more effective in limiting GVHD. Pharmacological blockade of A2A receptor exacerbated GVHD in WT recipients, but not in CD73 KO recipients, suggesting that A2 receptor signaling is primarily implicated in CD73-mediated GVHD protection. Moreover, pharmacological blockade of CD73 enzymatic activity induced stronger alloreactive T cell activity, worsened GVHD and enhanced the graft-versus-leukemia (GVL) effect. These findings suggest that both donor and recipient CD73 protects against GVHD but also limits GVL effects. Thus, either enhancing or blocking CD73 activity has great potential clinical application in allogeneic bone marrow transplants.
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Greater scaffold permeability promotes growth of osteoblastic cells in a perfused bioreactor.
J Tissue Eng Regen Med
PUBLISHED: 01-26-2013
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Pore size and porosity have been widely acknowledged as important structural factors in tissue-engineered scaffolds. In fact, scaffolds with similar pore size and porosity can provide important and varied permeability due to different pore shape, interconnectivity and tortuosity. However, the effects of scaffold permeability on seeded cells remains largely unknown during tissue regeneration in vitro. In this study, we measured the Darcy permeability (K) of tri-calcium phosphate scaffolds by distributed them into three groups: Low, Medium and High. As a result, the effects of scaffold permeability on cell proliferation, cellular activity and growth in the inner pores were investigated in perfused and static cultures in vitro. Results demonstrated that higher permeable scaffolds exhibited superior performance during bone regeneration in vitro and the advantages of higher scaffold permeability were amplified in perfused culture. Based on these findings, scaffold permeability should be considered in future scaffold fabrications. Copyright © 2013 John Wiley & Sons, Ltd.
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Understanding the high photocatalytic activity of (B, Ag)-codoped TiO2 under solar-light irradiation with XPS, solid-state NMR, and DFT calculations.
J. Am. Chem. Soc.
PUBLISHED: 01-22-2013
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The origin of the exceptionally high activity of (B, Ag)-codoped TiO(2) catalysts under solar-light irradiation has been investigated by XPS and (11)B solid-state NMR spectroscopy in conjunction with density functional theory (DFT) calculations. XPS experimental results demonstrated that a portion of the dopant Ag (Ag(3+)) ions were implanted into the crystalline lattice of (B, Ag)-codoped TiO(2) and were in close proximity to the interstitial B (B(int.)) sites, forming [B(int.)-O-Ag] structural units. In situ XPS experiments were employed to follow the evolution of the chemical states of the B and Ag dopants during UV-vis irradiation. It was found that the [B(int.)-O-Ag] units could trap the photoinduced electron to form a unique intermediate structure in the (B, Ag)-codoped TiO(2) during the irradiation, which is responsible for the photoinduced shifts of the B 1s and Ag 3d peaks observed in the in situ XPS spectra. Solid-state NMR experiments including (11)B triple-quantum and double-quantum magic angle spinning (MAS) NMR revealed that up to six different boron species were present in the catalysts and only the tricoordinated interstitial boron (T*) species was in close proximity to the substitutional Ag species, leading to formation of [T*-O-Ag] structural units. Furthermore, as demonstrated by DFT calculations, the [T*-O-Ag] structural units were responsible for trapping the photoinduced electrons, which prolongs the life of the photoinduced charge carriers and eventually leads to a remarkable enhancement in the photocatalytic activity. All these unprecedented findings are expected to be crucial for understanding the roles of B and Ag dopants and their synergistic effect in numerous titania-mediated photocatalytic reactions.
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atf4 promotes ?-catenin expression and osteoblastic differentiation of bone marrow mesenchymal stem cells.
Int. J. Biol. Sci.
PUBLISHED: 01-17-2013
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Bone marrow mesenchymal stem cells (MSCs) can differentiate into multiple cell types including osteoblasts. How this differentiation process is controlled, however, is not completely understood. Here we show that activating transcription factor 4 (ATF4) plays a critical role in promoting bone marrow MSC differentiation towards the osteoblast lineage. Ablation of the Atf4 gene blocked the formation of osteoprogenitors and inhibited osteoblast differentiation without affecting the expansion and formation of MSCs in bone marrow cultures. Loss of ATF4 dramatically reduced the level of ?-catenin protein in MSCs in vitro and in osteoblasts/osteoprogenitors located on trabecular and calvarial surfaces. Loss of ATF4 did not decrease the expression of major canonical Wnt/?-catenin signaling components such as Wnt3a, Wnt7b, Wnt10b, Lrp5, and Lrp6 in MSCs. Furthermore, shRNA knockdown of ATF4 expression decreased the level of ?-catenin protein in MC-4 preosteoblasts. In contrast, overexpression of ATF4 increased ?-catenin protein levels in MC-4 cells. Finally, ATF4 and ?-catenin formed a protein-protein complex in COS-7 cells coexpressing both factors or in MC-4 preosteoblastic cells. This study establishes a new role of ATF4 in controlling the ?-catenin protein levels and MSC differentiation towards the osteoblast lineage.
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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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