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Find video protocols related to scientific articles indexed in Pubmed.
mReg2 inhibits nuclear entry of apoptosis-inducing factor in mouse insulinoma cells.
Growth Factors
PUBLISHED: 11-06-2014
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Abstract We have reported earlier that murine-regenerating gene mReg2 protects MIN6 mouse insulinoma cells from ER stress and caspase-mediated apoptosis. In apoptotic cells, DNA damage is induced by the nuclear translocation of mitochondrial apoptosis-inducing factor (AIF). Here we tested the hypothesis that mReg2 may regulate Scythe and/or hsp70 which influence the nuclear import of AIF. Treatment with thapsigargin (Tg) or doxorubicin induced an increase in nuclear AIF in MIN6 cells carrying the empty transfection vector (MIN6-VC) but not in cells overexpressing mReg2 (MIN6-mReg2). On one hand, nuclear Scythe was higher in the nucleus of MIN6-mReg2 compared with that in MIN6-VC cells. mReg2 did not alter the expression of AIF or Scythe. On the other hand, mReg2 induced the expression of hsp70 which is known to promote cytosolic retention of AIF. We conclude that mReg2 inhibits AIF-mediated apoptosis by promoting the nuclear presence of Scythe and inducing hsp70.
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Recent advances in asymmetric organocatalysis mediated by bifunctional amine-thioureas bearing multiple hydrogen-bonding donors.
Chem. Commun. (Camb.)
PUBLISHED: 11-04-2014
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Organocatalysis has proven to be one of the most rapidly developing and competitive research areas in asymmetric catalysis since 2000, and has become a third branch besides biocatalysis and transition metal catalysis. In this feature article, recent progress from our research group on asymmetric organocatalysis, focusing on fine-tunable amine-thiourea catalysis, is described. Design of novel bifunctional amine-thiourea organocatalysts based upon the synergistic activation strategy via multiple hydrogen bonds and their applications in asymmetric C-C, C-N, and C-S bond-forming reactions under mild conditions are discussed in detail. The most attractive feature of the newly designed fine-tunable amine-thiourea catalysts is the incorporation of multiple hydrogen bonding donors and stereogenic centers.
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Involvement of superoxide and nitric oxide in BRAF(V600E) inhibitor PLX4032-induced growth inhibition of melanoma cells.
Integr Biol (Camb)
PUBLISHED: 11-04-2014
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The BRAF(V600E) inhibitor PLX4032 (Vemurafenib) is an FDA-approved new drug for the treatment of metastatic melanomas, which specifically inhibits the RAS/MEK/ERK signaling pathway to control cell proliferation and adhesion. However, no study has been carried out to investigate the role of intracellular oxidative balance in PLX4032-induced tumor growth inhibition. Herein, for the first time, superoxide (O2?(-)) and nitric oxide (NO) generated from PLX4032-challenged melanoma cells were monitored using electrochemical sensors and conventional fluorescein staining techniques. Impacts of superoxide dismutase (SOD) and NG-monomethyl-l-arginine monoacetate (l-NMMA), a nitric oxide synthase inhibitor, were also examined to demonstrate the specificity of ROS/NO generation and its biological consequences. PLX4032 specifically triggers production of O2?(-) and NO from BRAF(V600E) mutant A375 cells. SOD and l-NMMA could abolish the PLX4032-induced increase in intracellular O2?(-) and NO production, thereby rescuing cell growth in BRAF mutant A375 cells (A375(BRAFV600E)). In addition, PLX4032 treatment could decrease the mitochondrial membrane potential in A375(BRAFV600E) cells. The results suggest that PLX4032 can selectively cause ROS production and depolarization of mitochondrial membranes, potentially initiating apoptosis and growth inhibition of PLX4032-sensitive cells. This work not only proposes a new mechanism for PLX4032-induced melanoma cell inhibition, but also highlights potential applications of electrochemical biosensors in cell biology and drug screening.
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Screw-Dislocation-Driven Growth of Two-Dimensional Few-Layer and Pyramid-like WSe2 by Sulfur-Assisted Chemical Vapor Deposition.
ACS Nano
PUBLISHED: 10-29-2014
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Two-dimensional (2D) layered tungsten diselenides (WSe2) material has recently drawn a lot of attention due to its unique optoelectronic properties and ambipolar transport behavior. However, direct chemical vapor deposition (CVD) synthesis of 2D WSe2 is not as straightforward as other 2D materials due to the low reactivity between reactants in WSe2 synthesis. In addition, the growth mechanism of WSe2 in such CVD process remains unclear. Here we report the observation of a screw-dislocation-driven (SDD) spiral growth of 2D WSe2 flakes and pyramid-like structures using a sulfur-assisted CVD method. Few-layer and pyramid-like WSe2 flakes instead of monolayer were synthesized by introducing a small amount of sulfur as a reducer to help the selenization of WO3, which is the precursor of tungsten. Clear observations of steps, helical fringes, and herringbone contours under atomic force microscope characterization reveal the existence of screw dislocations in the as-grown WSe2. The generation and propagation mechanisms of screw dislocations during the growth of WSe2 were discussed. Back-gated field-effect transistors were made on these 2D WSe2 materials, which show on/off current ratios of 10(6) and mobility up to 44 cm(2)/(V·s).
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5,10-Methylenetetrahydrofolate Reductase Polymorphisms and Colon Cancer Risk: a Meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-24-2014
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Previous studies investigating the association between 5,10-methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and colon cancer risk have generated conflicting results. The aim of our meta-analysis was to clarify the precise association. A systematic literature search was conducted to identify all relevant studies. Pooled odds ratio (ORs) with 95% confidence interval (CI) were used to estimate the strength of the association. In this meta-analysis, a total of 13 articles, involving 5,386 cases and 8,017 controls met the inclusion criteria. Overall, a significant association was found between colon cancer risk and the MTHFR C667 polymorphism (TT vs CC+CT: OR=0.79; 95%CI=0.65-0.96; p=0.017). Stratification by ethnicity revealed that MTHFRC667 was associated with colon cancer risk in the non-Asian group (TT vs CC+CT:OR=0.77, 95%CI=0.68-0.89, p=0.000; TT vs CC: OR=0.84, 95%CI=0.73-0.97, p=0.016). Stratification by source of control indicated that MTHFR C667 also correlated with colon cancer risk in the population-based subgroup (TT vs CC: OR=0.85, 95%CI=0.74-0.97, p=0.017; TT vs CC+CT: OR=0.78, 95%CI=0.68-0.89, p=0.000) and hospital-based subgroup (TT vs CC+CT: OR=0.65, 95%CI=0.49-0.86, p=0.003). However, risk was significantly increased for MTHFR A1298C polymorphisms and colon cancer risk in hospital-based studies (C vs A: OR=1.52, 95%CI=1.26-1.83, p=0.000; CC+AC vs AA: OR=1.93, 95%CI=1.47-2.49, p=0.000) but reduced in population-based studies (CC vs AA: OR=0.83, 95%CI=0.70-0.99, p=0.042). In conclusion, the results of our meta-analysis suggest that the MTHFR C667 polymorphism is associated with reduced colon cancer risk, especially for non-Asian populations.
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[Study on physiological trait changes in growth process of different varieties of Lonicera japonica].
Zhong Yao Cai
PUBLISHED: 10-23-2014
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To study the physiological trait changes in the growth process of different varieties of Lonicera japonica, and to explore the growth regularity.
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Two new compounds from Ganoderma lucidum.
J Asian Nat Prod Res
PUBLISHED: 10-09-2014
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Two pairs of new enantiomers, lucidulactones A and B (1 and 2), and two known compounds were isolated from Ganoderma lucidum. Their structures were determined by means of spectroscopic methods. The chiral HPLC was used to separate the ( - )- and (+)-antipodes of the new compounds.
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Electroacupuncture at Feishu (BL13) and Zusanli (ST36) down-regulates the expression of orexins and their receptors in rats with chronic obstructive pulmonary disease.
J Integr Med
PUBLISHED: 10-09-2014
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Inflammation and lung function decline are the main pathophysiological features of chronic obstructive pulmonary disease (COPD). Acupuncture can improve lung function in patients with COPD, but the underlying mechanisms are not well understood. Orexins (OXs), which are found in peripheral plasma, are neuropeptides that regulate respiration and their levels are related to COPD. Therefore, we hypothesized that acupuncture might alter OXs, reduce lung inflammation and improve lung function in COPD.
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Flexible and Stretchable Lithium-Ion Batteries and Supercapacitors Based on Electrically Conducting Carbon Nanotube Fiber Springs.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 09-23-2014
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The construction of lightweight, flexible and stretchable power systems for modern electronic devices without using elastic polymer substrates is critical but remains challenging. We have developed a new and general strategy to produce both freestanding, stretchable, and flexible supercapacitors and lithium-ion batteries with remarkable electrochemical properties by designing novel carbon nanotube fiber springs as electrodes. These springlike electrodes can be stretched by over 300?%. In addition, the supercapacitors and lithium-ion batteries have a flexible fiber shape that enables promising applications in electronic textiles.
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Differential gene expression pattern in hypothalamus of chickens during fasting-induced metabolic reprogramming: Functions of glucose and lipid metabolism in the feed intake of chickens.
Poult. Sci.
PUBLISHED: 09-19-2014
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Fasting-induced hypothalamic metabolic reprogramming is involved in regulating energy homeostasis and appetite in mammals, but this phenomenon remains unclear in poultry. In this study, the expression patterns of a panel of genes related to neuropeptides, glucose, and lipid metabolism enzymes in the hypothalamus of chickens during fasting and refeeding were characterized by microarray analysis and quantitative PCR. Results showed that 48 h of fasting upregulated (P < 0.05) the mRNA expressions of orexigenic neuropeptide Y and agouti-related protein but downregulated (P < 0.05) that of anorexigenic neuropeptide pro-opiomelanocortin; growth hormone-releasing hormone; islet amyloid polypeptide; thyroid-stimulating hormone, ?; and glycoprotein hormones, ? polypeptide. After 48 h of fasting, the mRNA expression of fatty acid ?-oxidation [peroxisome proliferator-activated receptor ? (PPAR?), carnitine palmitoyltransferase 1A, and forkhead box O1], energy sensor protein [sirtuin 1 (SIRT1) and forkhead box O1], and glycolysis inhibitor (pyruvate dehydrogenase kinase, isozyme 4) were enhanced, but that of fatty acid synthesis and transport associated genes (acetyl-CoA carboxylase ?, fatty acid synthase, apolipoprotein A-I, endothelial lipase, and fatty acid binding protein 7) were suppressed. Liver and muscle also demonstrated similar expression patterns of genes related to glucose and lipid metabolism with hypothalamus, except for that of acetyl-CoA carboxylase ?, acyl-CoA synthetase long-chain family member 4, and apolipoprotein A-I. The results of intracerebroventricular (ICV) injection experiments confirmed that ?-lipoic acid (ALA, pyruvate dehydrogenase kinase, isozyme 4 inhibitor, 0.10 ?mol) and NADH (SIRT1 inhibitor, 0.80 ?mol) significantly suppressed the appetite of chickens, whereas 2-deoxy-d-glucose (glycolytic inhibitor, 0.12 to 1.20 ?mol) and NAD(+) (SIRT1 activator, 0.08 to 0.80 ?mol) increased feed intake in chickens. The orexigenic effect of NAD(+) was also blocked by cotreatment with NADH. However, ICV injection of either GW7647 (PPAR? agonist) or GW6471 (PPAR? antagonist) showed no effects on feed intake. Results suggested that hypothalamic glycolysis (inhibited by ALA and promoted by 2-deoxy-d-glucose) and SIRT1 (inhibited by NADH and promoted by NAD(+)), not PPAR?, were probably involved in feed intake regulation in chickens.
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In vivo electrophysiological recording techniques for the study of neuropathic pain in rodent models.
Curr Protoc Pharmacol
PUBLISHED: 09-02-2014
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Neuropathic pain develops following nerve injury, and is a chronic pain syndrome that can persist long after repair of a wound or removal of the neurological insult. This condition remains poorly treated, not least because of a lack of mechanism-based therapeutics. Clinically, neuropathic pain is characterized by three major symptoms: thermal or mechanical allodynia (pain sensation in response to previously non-noxious stimuli); hyperalgesia (enhanced pain sensation to noxious stimulation); and spontaneous, ongoing pain. These clinical symptoms can be modeled in rodent neuropathic pain models using behavioral and electrophysiological readouts. This unit describes techniques designed to record pathophysiological electrical activity associated with neuropathic pain at the level of the periphery, in single fibers of primary sensory neurons, and from wide dynamic range (WDR) neurons of the dorsal horn of the spinal cord. These techniques can be employed in both naïve animals and in animal models of neuropathy to investigate fundamental mechanisms contributing to the neuropathic pain state and the site, mode, and mechanism of action of putative analgesics. Curr. Protoc. Pharmacol. 66:11.15.1-11.15.26. © 2014 by John Wiley & Sons, Inc.
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Phragmalin Limonoids from the Stem Barks of Chukrasia tabularis var. velutina.
Planta Med.
PUBLISHED: 08-25-2014
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Seven new phragmalin limonoids, chukvelutilides I-O (1-7), were isolated from the stem barks of Chukrasia tabularis var. velutina. Their structures were elucidated by extensive spectroscopic analysis. Among them, compound 1 showed moderate lethal activity against brine shrimp larvae, with an LC50 value of 84.1?µM.
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CTAG-containing cleavage site profiling to delineate Salmonella into natural clusters.
PLoS ONE
PUBLISHED: 08-19-2014
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The bacterial genus Salmonella contains thousands of serotypes that infect humans or other hosts, causing mild gastroenteritis to potentially fatal systemic infections in humans. Pathogenically distinct Salmonella serotypes have been classified as individual species or as serological variants of merely one or two species, causing considerable confusion in both research and clinical settings. This situation reflects a long unanswered question regarding whether the Salmonella serotypes exist as discrete genetic clusters (natural species) of organisms or as phenotypic (e.g. pathogenic) variants of a single (or two) natural species with a continuous spectrum of genetic divergence among them. Our recent work, based on genomic sequence divergence analysis, has demonstrated that genetic boundaries exist among Salmonella serotypes, circumscribing them into clear-cut genetic clusters of bacteria.
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Wnt5a is associated with the differentiation of bone marrow mesenchymal stem cells in vascular calcification by connecting with different receptors.
Mol Med Rep
PUBLISHED: 08-05-2014
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Vascular calcification significantly affects the health of the elderly. Increasing evidence proved that vascular calcification is an actively regulated osteogenic process. The osteochondrocytic differentiation of mesenchymal stem cells (MSCs) is a significant step of osteogenic processes. The Wnt pathways has been identified as contributing to the regulation of osteogenic mineralization during development and disease. However, it remains unknown whether these MSCs in the vascular calcification differentiate into normal vascular smooth muscle cells (VSMCs) in vivo in order to treat damaged vascular tissue or into calcified VSMCs to aggravate calcification correlated to the Wnt pathways. Thus, it is necessary to analyze the mechanisms of MSC differentiation in detail. In the present study a cell?cell co?culturing in vitro system was used to observe MSCs that directly interact with normal or calcified VSMCs during calcification and to investigate the gene expression of the Wnt pathways during the process. Direct co?cultures were established by seeding two different cell types, VSMCs or calcified VSMCs, or a mixture of both at ratios of 5,000:5,000 cells/1.7 cm2 onto either gelatin?coated 1.7?cm2 chamber slides for immunohistochemical analysis or gelatin?coated 75?cm2 tissue culture flasks for protein or RNA isolation. Osteoblastic differentiation was evaluated by examining the cell morphology and assessing the activity of alkaline phosphatase in the cell lysates by alkaline phosphatase staining. Additionally, the mRNA expression levels of the genes encoding for proteins involved in the Wnt signaling proteins, Wnt5A, LRP6, Ror2, c?Jun?N?terminal kinase and ??catenin, were assessed in each group. The present study demonstrated that Wnts are expressed in the progress of differentiation of MSCs during calcification. MSCs can differentiate into different cell phenotypes when there is direct cell?cell contact with VSMCs or calcified VSMCs, and the Wnt5a/Ror2 signaling pathway may be associated with the determination of differentiation of MSCs in this process.
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[Changes of IFN-gamma, IL-4 and T cells in Schistosoma japonicum-infected mice after praziquantel treatment].
Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi
PUBLISHED: 07-29-2014
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To investigate the serum levels of IFN-gamma and IL-4, and the dynamic changes of IFN-gamma-specific and IL-4-specific lymphocytes in mice with Schistosoma japonicum infection after treatment by praziquantel.
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Ultrasound promoted catalytic liquid-phase dehydrogenation of isopropanol for Isopropanol-Acetone-Hydrogen chemical heat pump.
Ultrason Sonochem
PUBLISHED: 07-28-2014
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The apparent kinetic of the ultrasound assisted liquid-phase dehydrogenation of isopropanol over Raney nickel catalyst was determined in the temperature range of 346-353K. Comparison of the effects of ultrasound and mechanical agitation on the isopropanol dehydrogenation was investigated. The ultrasound assisted dehydrogenation rate was significantly improved when relatively high power density was used. Moreover, the Isopropanol-Acetone-Hydrogen chemical heat pump (IAH-CHP) with ultrasound irradiation, in which the endothermic reaction is exposure to ultrasound, was proposed. A mathematical model was established to evaluate its energy performance in term of the coefficient of performance (COP) and the exergy efficiency, into which the apparent kinetic obtained in this work was incorporated. The operating performances between IAH-CHP with ultrasound and mechanical agitation were compared. The results indicated that the superiority of the IAH-CHP system with ultrasound was present even if more than 50% of the power of the ultrasound equipment was lost.
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The possible mechanism of Parkinson's disease progressive damage and the preventive effect of GM1 in the rat model induced by 6-hydroxydopamine.
Brain Res.
PUBLISHED: 07-26-2014
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The progressive pathogenesis and prevention of Parkinson's disease (PD) remains unknown at present. Therefore, the present study aimed to investigate the possible progressive pathogenesis and prevention of PD. Our study investigated the content of glutamate, mitochondria calcium, calmodulin, malonaldehyde and trace elements in striatum, cerebral cortex and hippocampus tissues; and the expression of bcl-2, bax and neuronal nitric oxide synthase (nNOS) in substantia nigra and striatum; and the change of apomorphine induced rotation behavior; and the treatmental effect of monosialotetrahexosylganglioside (GM1) intraperitoneal administration for 14 days in a PD rat model induced by 6-hydroxydopamine. The results revealed that the content of glutamate significantly decreased, and that of mitochondria calcium, calmodulin, malonaldehyde and ferrum significantly increased in striatum, cerebral cortex and hippocampus tissues; the content of magnesium significantly decreased, and that of cuprum and zinc significantly increased in cerebral cortex; the expression of bcl-2 significantly decreased, and that of bax and nNOS significantly increased in substantia nigra and striatum in PD rat. GM1 can partially improve the apomorphine induced rotation behavior and changes of glutamate, mitochondria calcium, calmodulin content in striatum of PD rat. Data suggested that dysfunction of excitatory amino acids neurotransmitter, calcium homeostasis disorder, abnormal metabolism of oxygen free radicals, abnormal trace elements distribution and/or deposition and excessive apoptosis participated in the progressive process of PD, and that GM1 could partially prevent the progressive damage.
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Efficacy of taxane-based regimens in a first-line setting for recurrent and/or metastatic Chinese patients with esophageal cancer.
Asian Pac. J. Cancer Prev.
PUBLISHED: 07-22-2014
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To compare the efficacy of taxane-based regimens in the first line setting retrospectively in Chinese patients with recurrent and/or metastatic esophageal cancer.
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Electrochromic Fiber-Shaped Supercapacitors.
Adv. Mater. Weinheim
PUBLISHED: 07-18-2014
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An electrochromic fiber-shaped super-capacitor is developed by winding aligned carbon nanotube/polyaniline composite sheets on an elastic fiber. The fiber-shaped supercapacitors demonstrate rapid and reversible chromatic transitions under different working states, which can be directly observed by the naked eye. They are also stretchable and flexible, and are woven into textiles to display designed signals in addition to storing energy.
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Modeling metabolism and stage-specific growth of Plasmodium falciparum HB3 during the intraerythrocytic developmental cycle.
Mol Biosyst
PUBLISHED: 07-09-2014
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The human malaria parasite Plasmodium falciparum goes through a complex life cycle, including a roughly 48-hour-long intraerythrocytic developmental cycle (IDC) in human red blood cells. A better understanding of the metabolic processes required during the asexual blood-stage reproduction will enhance our basic knowledge of P. falciparum and help identify critical metabolic reactions and pathways associated with blood-stage malaria. We developed a metabolic network model that mechanistically links time-dependent gene expression, metabolism, and stage-specific growth, allowing us to predict the metabolic fluxes, the biomass production rates, and the timing of production of the different biomass components during the IDC. We predicted time- and stage-specific production of precursors and macromolecules for P. falciparum (strain HB3), allowing us to link specific metabolites to specific physiological functions. For example, we hypothesized that coenzyme A might be involved in late-IDC DNA replication and cell division. Moreover, the predicted ATP metabolism indicated that energy was mainly produced from glycolysis and utilized for non-metabolic processes. Finally, we used the model to classify the entire tricarboxylic acid cycle into segments, each with a distinct function, such as superoxide detoxification, glutamate/glutamine processing, and metabolism of fumarate as a byproduct of purine biosynthesis. By capturing the normal metabolic and growth progression in P. falciparum during the IDC, our model provides a starting point for further elucidation of strain-specific metabolic activity, host-parasite interactions, stress-induced metabolic responses, and metabolic responses to antimalarial drugs and drug candidates.
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Biodegradable polylactide microspheres enhance specific immune response induced by Hepatitis B surface antigen.
Hum Vaccin Immunother
PUBLISHED: 06-24-2014
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Hepatitis B (HB) infection caused by Hepatitis B virus (HBV) is the most common liver disease in the world. HB vaccine, when administered in conjunction with alum adjuvants, induces Th2 immunity that confers protection against HBV. However, currently available vaccine formulations and adjuvants do not elicit adequate Th1 and CTL responses that are important for prevention of maternal transmission of the virus. Microspheres synthesized from poly (D, L-lactide-co-glycolide) (PLGA) or poly (D, L-lactide) (PLA) polymers have been considered as promising tools for in vivo delivery of antigens and drugs. Here we describe PLA microspheres synthesized by premix membrane emulsification method and their application in formulating a new microsphere based HB vaccine. To evaluate the immunogenicity of this microsphere vaccine, BALB/c mice were immunized with microsphere vaccine and a series of immunological assays were conducted. Results of Enzyme-linked ImmunoSpot (ELISPOT) assays revealed that the number of interferon-gamma (IFN-?)-producing splenocytes and CD8(+) T cells increased significantly in the microsphere vaccine group. Microsphere vaccine group showed enhanced specific cell lysis when compared with HB surface antigen (HBsAg) only group in (51)Cr cytotoxicity assays. Moreover, microsphere vaccine elicited a comparable level of antibody production as that of HB vaccine administered with alum adjuvant. We show that phagocytosis of HBsAg by dendritic cells is more pronounced in microsphere vaccine group when compared with other control groups. These results clearly demonstrate the potential of using PLA microspheres as effective HB vaccine adjuvants for an enhanced Th1 immune response.
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GIL, a new c-di-GMP-binding protein domain involved in regulation of cellulose synthesis in enterobacteria.
Mol. Microbiol.
PUBLISHED: 06-11-2014
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In contrast to numerous enzymes involved in c-di-GMP synthesis and degradation in enterobacteria, only a handful of c-di-GMP receptors/effectors have been identified. In search of new c-di-GMP receptors, we screened the Escherichia coli?ASKA overexpression gene library using the Differential Radial Capillary Action of Ligand Assay (DRaCALA) with fluorescently and radioisotope-labelled c-di-GMP. We uncovered three new candidate c-di-GMP receptors in E. coli and characterized one of them, BcsE. The bcsE gene is encoded in cellulose synthase operons in representatives of Gammaproteobacteria and Betaproteobacteria. The purified BcsE proteins from E. coli, Salmonella enterica and Klebsiella pneumoniae bind c-di-GMP via the domain of unknown function, DUF2819, which is hereby designated GIL, GGDEF I-site like domain. The RxGD motif of the GIL domain is required for c-di-GMP binding, similar to the c-di-GMP-binding I-site of the diguanylate cyclase GGDEF domain. Thus, GIL is the second protein domain, after PilZ, dedicated to c-di-GMP-binding. We show that in S.?enterica, BcsE is not essential for cellulose synthesis but is required for maximal cellulose production, and that c-di-GMP binding is critical for BcsE function. It appears that cellulose production in enterobacteria is controlled by a two-tiered c-di-GMP-dependent system involving BcsE and the PilZ domain containing glycosyltransferase BcsA.
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Aligned epitaxial SnO2 nanowires on sapphire: growth and device applications.
Nano Lett.
PUBLISHED: 05-27-2014
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Semiconducting SnO2 nanowires have been used to demonstrate high-quality field-effect transistors, optically transparent devices, photodetectors, and gas sensors. However, controllable assembly of rutile SnO2 nanowires is necessary for scalable and practical device applications. Here, we demonstrate aligned, planar SnO2 nanowires grown on A-plane, M-plane, and R-plane sapphire substrates. These parallel nanowires can reach 100 ?m in length with sufficient density to be patterned photolithographically for field-effect transistors and sensor devices. As proof-of-concept, we show that transistors made this way can achieve on/off current ratios on the order of 10(6), mobilities around 71.68 cm(2)/V·s, and sufficiently high currents to drive external organic light-emitting diode displays. Furthermore, the aligned SnO2 nanowire devices are shown to be photosensitive to UV light with the capability to distinguish between 254 and 365 nm wavelengths. Their alignment is advantageous for polarized UV light detection; we have measured a polarization ratio of photoconductance (?) of 0.3. Lastly, we show that the nanowires can detect NO2 at a concentration of 0.2 ppb, making them a scalable, ultrasensitive gas sensing technology. Aligned SnO2 nanowires offer a straightforward method to fabricate scalable SnO2 nanodevices for a variety of future electronic applications.
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Self-healable electrically conducting wires for wearable microelectronics.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 05-09-2014
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Electrically conducting wires play a critical role in the advancement of modern electronics and in particular are an important key to the development of next-generation wearable microelectronics. However, the thin conducting wires can easily break during use, and the whole device fails to function as a result. Herein, a new family of high-performance conducting wires that can self-heal after breaking has been developed by wrapping sheets of aligned carbon nanotubes around polymer fibers. The aligned carbon nanotubes offer an effective strategy for the self-healing of the electric conductivity, whereas the polymer fiber recovers its mechanical strength. A self-healable wire-shaped supercapacitor fabricated from a wire electrode of this type maintained a high capacitance after breaking and self-healing.
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Free-standing LiNi0.5Mn1.5O4/carbon nanofiber network film as lightweight and high-power cathode for lithium ion batteries.
ACS Nano
PUBLISHED: 04-28-2014
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Lightweight and high-power LiNi0.5Mn1.5O4/carbon nanofiber (CNF) network electrodes are developed as a high-voltage cathode for lithium ion batteries. The LiNi0.5Mn1.5O4/CNF network electrodes are free-standing and can be used as a cathode without using any binder, carbon black, or metal current collector, and hence the total weight of the electrode is highly reduced while keeping the same areal loading of active materials. Compared with conventional electrodes, the LiNi0.5Mn1.5O4/CNF network electrodes can yield up to 55% reduction in total weight and 2.2 times enhancement in the weight percentage of active material in the whole electrode. Moreover, the LiNi0.5Mn1.5O4/carbon nanofiber (CNF) network electrodes showed excellent current rate capability in the large-current test up to 20C (1C = 140 mAh/g), when the conventional electrodes showed almost no capacity at the same condition. Further analysis of polarization resistance confirmed the favorable conductivity from the CNF network compared with the conventional electrode structure. By reducing the weight, increasing the working voltage, and improving the large-current rate capability simultaneously, the LiNi0.5Mn1.5O4/CNF electrode structure can highly enhance the energy/power density of lithium ion batteries and thus holds great potential to be used with ultrathin, ultralight electronic devices as well as electric vehicles and hybrid electric vehicles.
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Expression of breast cancer resistance protein in peripheral T cell subsets from HIV?1?infected patients with antiretroviral therapy.
Mol Med Rep
PUBLISHED: 04-07-2014
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The aim of the present study was to investigate the expression of breast cancer resistance protein (BCRP) in peripheral T cell subsets of human immunodeficiency virus 1 (HIV?1)?infected patients, and to analyze the association between the levels of BCRP expression and disease progression in HIV?1 infection. Peripheral blood mononuclear cells (PBMCs) were obtained from HIV?1?infected patients (n=118), including 92 patients with antiretroviral therapy (ART) and 26 patients without a history of ART. Control samples from 30 healthy donors were also analyzed. The expression levels of BCRP in T cells were evaluated by flow cytometry. A high inter?individual variability was observed in CD4+ and CD8+ T cells in the HIV?1?infected patients and healthy donors; however, the analyzed expression levels of BCRP were significantly higher in the HIV?1?infected group with ART than those in the group with no history of ART (P<0.01). Furthermore, the frequency of BCRP?expressing T cells was inversely correlated with CD4+ and CD8+ T cell counts in HIV?1?infected patients with ART. The results suggested that BCRP expression varied among HIV?1?infected patients and healthy donors but was significantly higher in HIV?1 patients undergoing ART. In conclusion, the present study suggested that overexpression of BCRP may be involved in disease progression of the HIV?1 infection and may participate in drug resistance to ART, thus contributing to the failure of highly active ART in HIV?1 therapeutics.
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Attenuation of unfolded protein response and apoptosis by mReg2 induced GRP78 in mouse insulinoma cells.
FEBS Lett.
PUBLISHED: 04-07-2014
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Murine regenerating (mReg) genes have been implicated in preserving islet cell biology. Expanding on our previous work showing that overexpression of mReg2 protects MIN6 insulinoma cells against streptozotocin-induced apoptosis, we now demonstrate that mReg2 induces glucose-regulated peptide 78 (GRP78) expression via the Akt-mTORC1 axis and protects MIN6 cells against ER stress induced by thapsigargin and glucolipotoxicity. Activation of mTORC1 activity results from both mReg2-induced increased mTOR phosphorylation as well as increased expression of Raptor and G?L. Inhibition of Akt and mTORC1 blunted the ability of mReg2 to induce GRP78 and attenuate unfolded protein response (UPR). Knockdown of GRP78 sensitized the cells overexpressing mReg2 to UPR without affecting its ability to activate Akt-mTORC1 signaling. Induced expression of mReg2 may protect insulin producing cells from ER stress in diabetes.
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Antidiabetic and antioxidative effect of jiang tang xiao ke granule in high-fat diet and low-dose streptozotocin induced diabetic rats.
Evid Based Complement Alternat Med
PUBLISHED: 03-28-2014
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Diabetes mellitus (DM), a kind of metabolic disease, is increasing over the last four decades in the world. The purpose of this study was to investigate the effect of Jiang Tang Xiao Ke (JTXK) granule, a naturally occurring ingredient from Chinese herbal medicines, on serum glucose, lipids, and oxidative stress in DM rats induced by high-fat diet and streptozotocin. JTXK granule 9?g/kg (based on crude herb equivalent) and pioglitazone 1.5?mg/kg (as a positive control for comparison) were orally administrated to DM rats for 4 weeks. Results showed that administration of JTXK granule reduced serum glucose, total cholesterol, triglyceride, and low density lipoprotein levels (by 12%, 33%, 57%, and 44%, resp.) but increased high-density lipoprotein level by 69%, compared with the drug-untreated DM rats. Serum malondialdehyde and nitric oxide levels were lowered (by 34% and 52%, resp.) associated with the elevation in serum superoxide dismutase levels (by 60%) after JTXK granule treatment. In addition, JTXK granule suppressed serum alanine aminotransferase activity (up to 50%) and alleviated pathological changes of pancreas and liver tissues in DM rats. The beneficial changes of pioglitazone on biomarkers were also found in DM rats. These findings suggested that JTXK granule may be an alternative medicine for the management of DM.
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Expression of bcl-2 and p53 in induction of esophageal cancer cell apoptosis by ECRG2 in combination with cisplatin.
Asian Pac. J. Cancer Prev.
PUBLISHED: 03-11-2014
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To investigate the mechanisms of induction of apoptosis of esophageal cancer cells by esophageal cancer-related gene 2 (ECRG2) in combination with cisplatin (DDP).
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A twisted wire-shaped dual-function energy device for photoelectric conversion and electrochemical storage.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 03-10-2014
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A wire-shaped energy device that can perform photoelectric conversion and electrochemical storage was developed through a simple but effective twisting process. The energy wire exhibited a high energy conversion efficiency of 6.58?% and specific capacitance of 85.03??F?cm(-1) or 2.13?mF?cm(-2), and the two functions were alternately realized without sacrificing either performance.
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Protective Effects of Poly (butyl) Cyanoacrylate Nanoparticles Containing Vasoactive Intestinal Peptide Against 6-Hydroxydopamine-Induced Neurotoxicity In Vitro.
J. Mol. Neurosci.
PUBLISHED: 03-04-2014
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The present study investigated brain delivery system of vasoactive intestinal peptide (VIP) adsorbed on poly (butyl cyanoacrylate) nanoparticles coated with polysorbate 80 (P80-poly (butyl) cyanoacrylate (PBCA)-nanoparticles (NPs)) and the neuroprotective effects on the formulation in the model of 6-hydroxydopamine (6-OHDA)-induced Parkinsonian dysfunction in the human neuroblastoma cell line SH-SY5Y. Drug-loaded nanoparticles were prepared by emulsion polymerization method using VIP and PBCA and then stirring with polysorbate 80. The resulting nanoparticles possessed high entrapment efficiency and favorable stability against CaCl2 or fetal bovine serum (FBS)-induced aggregation. Use of fluorescein isothiocyanate (FITC)-conjugated polysorbate 80-PBCA nanoparticles in confocal microscopy revealed that nanoparticles are located inside, while the FITC solution could not penetrate into the cells. The blank nanoparticles showed no significant effects on cell viability, indicating that they had no role in protection; however, polysorbate 80-modified VIP-loading PBCA nanoparticles showed enhanced cell viability compared to free VIP in 6-OHDA-mimic cellular model of Parkinson's disease. In addition, the nanoparticles strikingly increased the anti-apoptosis activity and restored the loss of mitochondrial membrane potential (MMP) significantly after the treatment of 6-OHDA. These results demonstrated that the activity of VIP was enhanced by polysorbate 80-PBCA nanoparticles compared to control solutions, suggesting that PBCA nanoparticles coated with polysorbate 80 could be an effective carrier system for VIP.
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Oral administration of baicalin and geniposide induces regression of atherosclerosis via inhibiting dendritic cells in ApoE-knockout mice.
Int. Immunopharmacol.
PUBLISHED: 02-25-2014
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Atherosclerosis is a systemic inflammatory disease characterized by the accumulation of dendritic cells (DCs) and other types of immune cells in atherosclerotic plaque. In this study, baicalin and geniposide were isolated from Scutellaria baicalensis Georgi and Gardenia jasminoids Ellis, which are the plants used in traditional Chinese medicine to treat a variety of inflammatory diseases. We then investigated whether baicalin and geniposide could induce regression of atherosclerotic lesions in ApoE-/- mice fed a high cholesterol diet and used as a model of atherosclerosis. Following model induction, these mice were treated with baicalin (100mg/kg), geniposide (100mg/kg), and then a mixture containing baicalin (100mg/kg) and geniposide (100mg/kg) administered daily by gavage for a period of 12weeks. The combined administration of baicalin and geniposide significantly reduced atherosclerotic lesions, and modulated the phenotype of dendritic cells in bone marrow and atherosclerotic plaque. Geniposide lowered both plasma lipid levels and DC numbers, while baicalin administered either alone or in combination with geniposide did not decrease plasma lipids. Our results suggest that baicalin and geniposide may have immune-regulatory effects and prevent the formation of atherosclerotic lesions by decreasing the DC numbers, and inhibit DC maturation in bone marrow and infiltration into lesions.
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Lidocaine-induced ASC apoptosis (tumescent vs. local anesthesia).
Aesthetic Plast Surg
PUBLISHED: 02-24-2014
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The purpose for the present study was to determine which anesthetic method, local anesthesia versus tumescent, is superior for liposuction in terms of adipose-derived stem cell (ASC) survival in lipoaspirate; which component, lidocaine versus lidocaine with epinephrine, in anesthetic solutions could affect ASC survival; and which mechanism, necrosis versus apoptosis, is involved in lidocaine-induced ASC death.
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DhhP, a cyclic di-AMP phosphodiesterase of Borrelia burgdorferi, is essential for cell growth and virulence.
Infect. Immun.
PUBLISHED: 02-24-2014
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Cyclic di-AMP (c-di-AMP) is a recently discovered second messenger in bacteria. Most of work on c-di-AMP signaling has been done in Gram-positive bacteria, firmicutes, and actinobacteria, where c-di-AMP signaling pathways affect potassium transport, cell wall structure, and antibiotic resistance. Little is known about c-di-AMP signaling in other bacteria. Borrelia burgdorferi, the causative agent of Lyme disease, is a spirochete that has a Gram-negative dual membrane. In this study, we demonstrated that B. burgdorferi BB0619, a DHH-DHHA1 domain protein (herein designated DhhP), functions as c-di-AMP phosphodiesterase. Recombinant DhhP hydrolyzed c-di-AMP to pApA in a Mn(2+)- or Mg(2+)-dependent manner. In contrast to c-di-AMP phosphodiesterases reported thus far, DhhP appears to be essential for B. burgdorferi growth both in vitro and in the mammalian host. Inactivation of the chromosomal dhhP gene could be achieved only in the presence of a plasmid-encoded inducible dhhP gene. The conditional dhhP mutant had a dramatic increase in intracellular c-di-AMP level in comparison to the isogenic wild-type strain. Unlike what has been observed in Gram-positive bacteria, elevated cellular c-di-AMP in B. burgdorferi did not result in an increased resistance to ?-lactamase antibiotics, suggesting that c-di-AMP's functions in spirochetes differ from those in Gram-positive bacteria. In addition, the dhhP mutant was defective in induction of the ?(S) factor, RpoS, and the RpoS-dependent outer membrane virulence factor OspC, which uncovers an important role of c-di-AMP in B. burgdorferi virulence.
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Elastic and wearable wire-shaped lithium-ion battery with high electrochemical performance.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 02-13-2014
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A stretchable wire-shaped lithium-ion battery is produced from two aligned multi-walled carbon nanotube/lithium oxide composite yarns as the anode and cathode without extra current collectors and binders. The two composite yarns can be well paired to obtain a safe battery with superior electrochemical properties, such as energy densities of 27?Wh?kg(-1) or 17.7?mWh?cm(-3) and power densities of 880?W?kg(-1) or 0.56?W?cm(-3), which are an order of magnitude higher than the densities reported for lithium thin-film batteries. These wire-shaped batteries are flexible and light, and 97?% of their capacity was maintained after 1000?bending cycles. They are also very elastic as they are based on a modified spring structure, and 84?% of the capacity was maintained after stretching for 200?cycles at a strain of 100?%. Furthermore, these novel wire-shaped batteries have been woven into lightweight, flexible, and stretchable battery textiles, which reveals possible large-scale applications.
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Reprint of "heated vegetable oils and cardiovascular disease risk factors".
Vascul. Pharmacol.
PUBLISHED: 02-08-2014
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Cardiovascular disease (CVD) is one of the leading major causes of morbidity and mortality worldwide. It may result from the interactions between multiple genetic and environmental factors including sedentary lifestyle and dietary habits. The quality of dietary oils and fats has been widely recognised to be inextricably linked to the pathogenesis of CVD. Vegetable oil is one of the essential dietary components in daily food consumption. However, the benefits of vegetable oil can be deteriorated by repeated heating that leads to lipid oxidation. The practice of using repeatedly heated cooking oil is not uncommon as it will reduce the cost of food preparation. Thermal oxidation yields new functional groups which may be potentially hazardous to cardiovascular health. Prolonged consumption of the repeatedly heated oil has been shown to increase blood pressure and total cholesterol, cause vascular inflammation as well as vascular changes which predispose to atherosclerosis. The harmful effect of heated oils is attributed to products generated from lipid oxidation during heating process. In view of the potential hazard of oxidation products, therefore this review article will provide an insight and awareness to the general public on the consumption of repeatedly heated oils which is detrimental to health.
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Heated vegetable oils and cardiovascular disease risk factors.
Vascul. Pharmacol.
PUBLISHED: 02-08-2014
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Cardiovascular disease (CVD) is one of the leading major causes of morbidity and mortality worldwide. It may result from the interactions between multiple genetic and environmental factors including sedentary lifestyle and dietary habits. The quality of dietary oils and fats has been widely recognised to be inextricably linked to the pathogenesis of CVD. Vegetable oil is one of the essential dietary components in daily food consumption. However, the benefits of vegetable oil can be deteriorated by repeated heating that leads to lipid oxidation. The practice of using repeatedly heated cooking oil is not uncommon as it will reduce the cost of food preparation. Thermal oxidation yields new functional groups which may be potentially hazardous to cardiovascular health. Prolonged consumption of the repeatedly heated oil has been shown to increase blood pressure and total cholesterol, cause vascular inflammation as well as vascular changes which predispose to atherosclerosis. The harmful effect of heated oils is attributed to products generated from lipid oxidation during heating process. In view of the potential hazard of oxidation products, therefore this review article will provide an insight and awareness to the general public on the consumption of repeatedly heated oils which is detrimental to health.
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Effect of ECRG2 in combination with cisplatin on the proliferation and apoptosis of EC9706 cells.
Exp Ther Med
PUBLISHED: 02-04-2014
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The aim of the present study was to explore the effect of esophageal cancer-related gene 2 (ECRG2) protein in combination with cisplatin (DDP) on the proliferation and apoptosis of esophageal cancer cells. A 3-(4, 5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT) assay was used to examine the effects of ECRG2 alone and ECRG2 in combination with DDP on the proliferation of EC9706 esophageal cancer cells. Hoechst 33258 staining was performed to analyze the effects of ECRG2 alone and ECRG2 in combination with DDP on apoptosis in the EC9706 cells. The expression levels of Bcl-2-associated X protein (Bax) mRNA and protein were determined by reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis, respectively. The results from the MTT assay revealed that ECRG2 inhibited the proliferation of EC9706 cells and that ECRG2 in combination with DDP had a greater inhibitory effect on cell proliferation. The antiproliferative effects were time- and concentration-dependent, within a certain range of concentrations. The Hoechst 33258 staining results demonstrated that the number of apoptotic cells following treatment with ECRG2 in combination with DDP for 24 h was higher than that following treatment with ECRG2 alone for the same duration. Western blot analysis and RT-PCR results revealed that the expression levels of Bax mRNA and protein were upregulated in cells treated with ECRG2 in combination with DDP compared with those in cells treated with ECRG2 alone. Thus, ECRG2 in combination with DDP had an enhanced inhibitory effect on EC9706 cell proliferation compared with that of ECRG2 alone, and an increased inductive effect on EC9706 cell apoptosis, possibly due to the upregulation of the expression of Bax.
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Echocardiographic diagnosis of sinus of Valsalva aneurysm: a 17-year (1995-2012) experience of 212 surgically treated patients from one single medical center in China.
Int. J. Cardiol.
PUBLISHED: 01-24-2014
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To evaluate the value of echocardiography in the diagnosis of different pathological patterns of sinus of Valsalva aneurysms (SVAs).
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Carbon nanotube and carbon nanorod-filled polyacrylonitrile electrospun stationary phase for ultrathin layer chromatography.
Anal. Chim. Acta
PUBLISHED: 01-23-2014
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The application of carbon nanotube or nanorod/polyacrylonitrile (PAN) composite electrospun nanofibrous stationary phase for ultrathin layer chromatography (UTLC) is described herein. Multi-walled carbon nanotubes (MWCNTs) and edge-plane carbon (EPC) nanorods were prepared and electrospun with the PAN polymer solution to form composite nanofibers for use as a UTLC stationary phase. The analysis of laser dyes demonstrated the feasibility of utilizing carbon nanoparticle-filled electrospun nanofibers as a UTLC stationary phase. The contribution of MWCNT or EPC in changing selectivity of the stationary phase was studied by comparing the chromatographic behavior among MWCNT-PAN plates, EPC-PAN plates and pure PAN plates. Carbon nanoparticles in the stationary phase were able to establish strong ?-? interactions with aromatic analytes. The separation of five polycyclic aromatic hydrocarbons (PAHs) demonstrated enhanced chromatographic performance of MWCNT-filled stationary phase by displaying substantially improved resolution and separation efficiency. Band broadening of the spots for MWCNT or EPC-filled UTLC stationary phases was also investigated and compared with that for pure PAN stationary phases. A 50% improvement in band dispersion was noted using the MWCNT based composite nanofibrous UTLC plates.
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Association of signaling transducers and activators of transcription 1 and systemic lupus erythematosus.
Autoimmunity
PUBLISHED: 01-20-2014
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Systemic lupus erythematosus (SLE) is complex autoimmune disease which involves various facets of the immune system. Signaling transducers and activators of transcription 1 (STAT1) belongs to the family of STAT transcription factors that mediate various biological responses. Recently, studies in both experimental animal models of lupus and patients with SLE have revealed expression and activation of STAT1 is closely associated with the pathogenesis of SLE. Moreover, increased production of interferons (IFNs) and aberrant activation of IFNs signaling, which is mechanistically linked to increased level of STAT1, are crucial for the development of SLE. Therefore, we will focus on the association of STAT1 and SLE based on recent understandings to render more information about the mechanisms of STAT1 might perform in. Hopefully, the information obtained will lead to a better understanding of the development and pathogenesis of systemic autoimmune diseases, as well as its clinical implications and therapeutic potential.
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Baicalin and geniposide attenuate atherosclerosis involving lipids regulation and immunoregulation in ApoE-/- mice.
Eur. J. Pharmacol.
PUBLISHED: 01-17-2014
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Baicalin and geniposide, which are respectively isolated from Scutellariae radix and Gardenia jasminoides, have been known to exhibit a number of pharmacological effects, including anti-inflammatory and anti-oxidant. Here, we primarily aimed to observe the protective effects of these two Chinese herbs on inhibiting the development of atherosclerosis in apolipoprotein E knockout mice via lipids regulation and immunoregulation. After the ApoE-/- mice with high-cholesterol diet had received 12-weeks? oral administration of either baicalin or geniposide (100 mg/kg), atherosclerotic plaque areas in aorta were measured and exhibited a prominent decrease in the treated mice. We then assayed serum lipids levels, serum Treg-cell-associated cytokines (TGF-?1 and IL-10) and the frequency of splenic Treg cells. We found that geniposide notably decreased serum TC and LDL-c. Both baicalin and geniposide treated mice showed much more splenic Treg cells and the correlated cytokines (TGF-?1 and IL-10). Foxp3, as the marker of Treg cell, was detected in atherosclerotic lesions, and we found that Foxp3 expression at both mRNA and protein levels was up-regulated in addition to increased Foxp3 positive Treg cells detected by immunohistochemistry in baicalin or geniposide treated mice. In conclusion, baicalin and geniposide up-regulated the expression of foxp3, promoted the number and function of Treg cells and ameliorated the atherosclerotic lesions progression partly through lipids regulation and immunoregulation.
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miR-21 and miR-375 microRNAs as candidate diagnostic biomarkers in squamous cell carcinoma of the larynx: association with patient survival.
Am J Transl Res
PUBLISHED: 01-01-2014
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The dismal outcome of laryngeal squamous cell carcinoma (SCC) patients highlights the need for novel prognostic biomarkers. The involvement of microRNAs in cancer and their potential as biomarkers of diagnosis and prognosis are becoming increasingly appreciated. We sought to identify microRNAs that exhibit altered expression in laryngeal SCC and to determine whether microRNA (miRNA) expression is predictive of disease progression and/or patient survival. The expression of two miRNAs, miR-21 and miR-375, was evaluated using total RNA isolated from freshly-frozen primary tumors and non-cancerous laryngeal squamous epithelial tissues and quantitative real-time polymerase chain reaction (qRT-PCR) analysis. We further analyzed the association between the expression of miRNAs and the clinicopathological features. A marked difference in the microRNA expression pattern was observed between tumors and non-cancerous tissue. MiR-21 and miR-375 were expressed at higher and lower levels, respectively, in the laryngeal SCC samples, compared to the normal samples (p < 0.01 and p < 0.001, respectively). There was no correlation between characteristics such as age, sex, clinical stage, and alcohol use, and the expression level of mir-21. The relative expression of mir-375 in laryngeal SCC was shown to be associated with localization of the tumor in these patients (p = 0.037) and with alcohol use (p < 0.05). Patients with high miR-21 or low miR-375 expression in tumor tissues had poorer prognoses compared to patients with lower miR-21 or higher miR-375 expression. Furthermore, the miR-21/miR-375 expression ratio was highly sensitive (0.94) and specific (0.94) for disease prediction. These data suggest that the pattern of microRNA expression in primary laryngeal SCC tissues is reflective of the disease status and that miR-21 and miR-375 expression levels, in particular, may serve as potential biomarkers with applications in the clinical setting.
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Sequential administration of carbon nanotubes and near-infrared radiation for the treatment of gliomas.
Front Oncol
PUBLISHED: 01-01-2014
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The objective was to use carbon nanotubes (CNT) coupled with near-infrared radiation (NIR) to induce hyperthermia as a novel non-ionizing radiation treatment for primary brain tumors, glioblastoma multiforme (GBM). In this study, we report the therapeutic potential of hyperthermia-induced thermal ablation using the sequential administration of carbon nanotubes (CNT) and NIR. In vitro studies were performed using glioma tumor cell lines (U251, U87, LN229, T98G). Glioma cells were incubated with CNTs for 24?h followed by exposure to NIR for 10?min. Glioma cells preferentially internalized CNTs, which upon NIR exposure, generated heat, causing necrotic cell death. There were minimal effects to normal cells, which correlate to their minimal uptake of CNTs. Furthermore, this protocol caused cell death to glioma cancer stem cells, and drug-resistant as well as drug-sensitive glioma cells. This sequential hyperthermia therapy was effective in vivo in the rodent tumor model resulting in tumor shrinkage and no recurrence after only one treatment. In conclusion, this sequence of selective CNT administration followed by NIR activation provides a new approach to the treatment of glioma, particularly drug-resistant gliomas.
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Association between hypertension and periodontitis: possible mechanisms.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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This review is to examine the current literatures on the relationship between periodontitis and hypertension as well as to explore the possible biological pathways underlying the linkage between these health conditions. Hypertension is one of the major risk factors for cardiovascular diseases. Oxidative stress and endothelial dysfunction are among the critical components in the development of hypertension. Inflammation has received much attention recently and may contribute to a pivotal role in hypertension. Periodontitis, a chronic low-grade inflammation of gingival tissue, has been linked to endothelial dysfunction, with blood pressure elevation and increased mortality risk in hypertensive patients. Inflammatory biomarkers are increased in hypertensive patients with periodontitis. Over the years, various researches have been performed to evaluate the involvement of periodontitis in the initiation and progression of hypertension. Many cross-sectional studies documented an association between hypertension and periodontitis. However, more well-designed prospective population trials need to be carried out to ascertain the role of periodontitis in hypertension.
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Aberrant activation of the WNT/?-catenin signaling pathway in lupus nephritis.
PLoS ONE
PUBLISHED: 01-01-2014
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The canonical WNT pathway has been implicated as playing important roles in the pathogenesis of a variety of kidney diseases. Recently, WNT pathway activity was reported to be elevated in the renal tissue of a lupus mouse model. This study aimed to evaluate the potential role of the WNT pathway in the pathogenesis of human lupus nephritis.
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Solution Ionic Strength Engineering As a Generic Strategy to Coat Graphene Oxide (GO) on Various Functional Particles and Its Application in High-Performance Lithium-Sulfur (Li-S) Batteries.
Nano Lett.
PUBLISHED: 12-30-2013
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A generic and facile method of coating graphene oxide (GO) on particles is reported, with sulfur/GO core-shell particles demonstrated as an example for lithium-sulfur (Li-S) battery application with superior performance. Particles of different diameters (ranging from 100 nm to 10 ?m), geometries, and compositions (sulfur, silicon, and carbon) are successfully wrapped up by GO, by engineering the ionic strength in solutions. Importantly, our method does not involve any chemical reaction between GO and the wrapped particles, and therefore, it can be extended to vast kinds of functional particles. The applications of sulfur/GO core-shell particles as Li-S battery cathode materials are further investigated, and the results show that sulfur/GO exhibit significant improvements over bare sulfur particles without coating. Galvanic charge-discharge test using GO/sulfur particles shows a specific capacity of 800 mAh/g is retained after 1000 cycles at 1 A/g current rate if only the mass of sulfur is taken into calculation, and 400 mAh/g if the total mass of sulfur/GO is considered. Most importantly, the capacity decay over 1000 cycles is less than 0.02% per cycle. The coating method developed in this study is facile, robust, and versatile and is expected to have wide range of applications in improving the properties of particle materials.
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Large-Scale Fabrication, 3D Tomography, and Lithium-Ion Battery Application of Porous Silicon.
Nano Lett.
PUBLISHED: 12-24-2013
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Recently, silicon-based lithium-ion battery anodes have shown encouraging results, as they can offer high capacities and long cyclic lifetimes. The applications of this technology are largely impeded by the complicated and expensive approaches in producing Si with desired nanostructures. We report a cost-efficient method to produce nanoporous Si particles from metallurgical Si through ball-milling and inexpensive stain-etching. The porosity of porous Si is derived from particles three-dimensional reconstructions by scanning transmission electron microscopy (STEM) tomography, which shows the particles highly porous structure when etched under proper conditions. Nanoporous Si anodes with a reversible capacity of 2900 mAh/g was attained at a charging rate of 400 mA/g, and a stable capacity above 1100 mAh/g was retained for extended 600 cycles tested at 2000 mA/g. The synthetic route is low-cost and scalable for mass production, promising Si as a potential anode material for the next-generation lithium-ion batteries with enhanced capacity and energy density.
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[Applications of acupuncture in relieving AIDS-related symptoms].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 11-16-2013
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AIDS is a serious threat to human health and has become a global public health problem. Highly active antiretroviral therapy (HAART) can effectively reduce AIDS mortality rate, but has limitations in improving the patients symptoms and improve quality of life. The literatures about the therapeutic effect of acupuncture and moxibustion on HIV/AIDS were reviewed. The symptoms of HIV/AIDS and the procedures of treatments were analyzed. The acupuncture intervention on HIV/AIDS was investigated. It showed that the acupuncture intervention may markedly improve the condition of HIV/AIDS. From a clinical point of view, we discussed the acupuncture treatment of AIDS-related symptoms, effectiveness and safety evaluation. It may contribute to build a comprehensive treatment system in which acupuncture is dominated for HIV/AIDS.
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[Intervention of immune 1 combined HAART on immune function in patients with HIV/AIDS reconstruction].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 11-16-2013
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To observe the effect of combination of Immune 1 and HAART on the CD4+ T cell count and its immune reconstitution rate.
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[Correlation study of HIV/AIDS abnormal immune activation and disease progression].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 11-16-2013
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To learn the levels of immune function and immune activation of HIV/AIDS patients in China and find the correlation between the immune activation and CD4+ T lymphocyte and disease progression. And discuss the relevance of immune activation with HIV/AIDS pathogenesis.
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Highly diastereoselective DABCO-catalyzed [3 + 3]-cycloaddition of 1,4-dithiane-2,5-diol with azomethine imines.
Org. Lett.
PUBLISHED: 10-24-2013
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An effective diastereoselective [3 + 3] cycloaddition of 1,4-dithiane-2,5-diol with azomethine imines catalyzed by DABCO is described. A variety of highly functionalized six-membered dinitrogen-fused heterocycles can be obtained in good yield with excellent diastereoselectivity, which was controlled by anomeric effect.
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Core-Sheath Carbon Nanostructured Fibers for Efficient Wire-Shaped Dye-Sensitized Solar Cells.
Adv. Mater. Weinheim
PUBLISHED: 10-22-2013
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A novel core-sheath carbon nanostructured fiber is created with high tensile strength, electrical conductivity, and electrocatalytic activity. In particular, the designed ribbon-like nanostructure on the outer surface favors the attachment and impregnation of a second functional phase that is critical for electronic devices. As a demonstration, novel wire-shaped dye-sensitized solar cells are produced with high energy conversion efficiencies up to 6.83%.
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A genetic role for macrophage migration inhibitory factor (MIF) in adult-onset Stills disease.
Arthritis Res. Ther.
PUBLISHED: 10-17-2013
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Adult-onset stills disease (AOSD) is a rare systemic inflammatory disorder in which abnormalities in inflammatory cytokines production appear to play a pathophysiological role. Our previous work has reported increased expression of macrophage migration inhibitory factor (MIF) and revealed its correlation with disease severity and activity in AOSD. A -173 G/C single nucleotide polymorphism (SNP) (rs755622) and a -794 CATT5-8 repeat (rs5844572) in the MIF promoter have been reported. In this study, we sought to explore the relationship between functional MIF promoter polymorphisms and MIF expression in AOSD.
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[Analysis of the protein expression and gene amplification of HER2 in gastric carcer].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 09-25-2013
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To explore the clinical significance of protein expression and gene amplification of HER2 in gastric cancer.
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E2F1: a potential therapeutic target for systematic lupus erythematosus.
Rheumatol. Int.
PUBLISHED: 09-14-2013
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E2F1 is a transcriptional activator, which binds to DNA, and regulates the expression of genes involved in the cell cycle progression. Many elegant studies have revealed that E2F1 plays a crucial role in regulating the apoptosis process of DC and T cells. In addition, the pathogenesis of SLE involves marked immune dysfunction, and in particular, the function of immunosuppressive elements of the immune system is impaired, including regulatory T cell function and DC. Thus, therapeutic agents targeting E2F1 might result in important innovative therapies for SLE.
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The effect of lipoaspirates cryopreservation on adipose-derived stem cells.
Aesthet Surg J
PUBLISHED: 08-21-2013
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Autologous fat grafting has gained popularity, particularly with the discovery of adipose-derived stem cells (ADSC). The possibility of freezing lipoaspirates (LA) for later use has intriguing clinical potential. However, the effect of LA cryopreservation on ADSC is unclear.
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Expression levels of P-glycoprotein in peripheral blood CD8+ T lymphocytes from HIV-1-infected patients on antiretroviral therapy.
Int. J. Mol. Med.
PUBLISHED: 08-09-2013
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In this study, we aimed to measure P-glycoprotein (P-gp) expression in CD8+ T lymphocytes of HIV-1-infected patients, to investigate how P-gp levels are affected by antiretroviral therapy (ART) in HIV-1 infection, and to assess the value of using P-gp expression to predict virologic response to ART. Peripheral blood mononuclear cells (PBMCs) were obtained from a cohort of HIV-1?infected patients in China: 140 patients on ART, and 49 ART-naïve patients. We also enrolled 24 healthy blood donors as the controls. The expression levels of P-gp in CD8+ T cells of HIV-1-infected patients were evaluated by quantitative reverse transcription PCR, ELISA and flow cytometry. A high inter-individual variability was observed in the CD8+ T cells of both HIV-1-infected patients and healthy donors; however, the expression levels of P-gp were significantly higher in the HIV-1-infected group on ART compared to the ART-naïve group. The relative proportion of P-gp+CD8+ T cells inversely correlated with the blood CD4+ T cell count in the HIV-1?infected patients on ART (r=-0.3343, P=0.0375). Groups of both good and poor responders showed significantly elevated levels of P-gp+CD8+ T cells. The percentage of P-gp+CD8+ T cells appeared to provide a sensitive estimate of the virologic response to ART compared to the CD4+ T cell count. Our results suggest that P-gp expression varies among HIV-1?infected patients, but is significantly higher in HIV-1?infected patients on ART. The overexpression of P-gp is involved in ART initiation during HIV-1 infection, and P-gp+CD8+ T cells may be an additional criterion for the evaluation of the antiretroviral response to ART.
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Organocatalytic asymmetric sulfa-Michael addition of thiols to ?,?-unsaturated hexafluoroisopropyl esters: expeditious access to (R)-thiazesim.
Org. Lett.
PUBLISHED: 06-17-2013
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A highly efficient organocatalytic asymmetric SMA reaction of hexafluoroisopropyl ?,?-unsaturated esters has been developed. Introducing electron-withdrawing hexafluoroisopropyl ester is crucial to enhancing the electrophilicity of unsaturated esters as SMA acceptors. The catalytic system performs well over a broad scope of ?,?-unsaturated esters and diversified thiols and provides facile access to (R)-thiazesim in a one-pot protocol.
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Interleukin-21 up-regulates interleukin-21R expression and interferon gamma production by CD8+ cells in SHIV-infected macaques.
Exp. Biol. Med. (Maywood)
PUBLISHED: 06-14-2013
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Interleukin-21 (IL-21) is produced primarily by CD4+ T cells and regulates immunity against human/simian immunodeficiency virus (HIV/SIV) infection. Activated CD8+ cells and their secreted interferon-gamma (IFN-?) are crucial for the control of acute HIV/SIV infection. However, whether IL-21 can regulate IFN-? production by CD8+ cells remains controversial. Rhesus macaques (RMs, n = 8) were infected with SHIV and the levels of plasma IL-21, IFN-? and the frequency of peripheral blood activated T cells were measured longitudinally. Following infection with SHIV, the levels of plasma IL-21 and IFN-? increased, peaked at 17 days postinfection and declined later. Furthermore, IL-21 induced IL-21 receptor (IL-21R) and IFN-?, perforin, but not granmyze B, expression in CD8+ cells from four selected SHIV-infected RMs. The regulatory effect of IL-21 on CD8+ cell function appeared to be associated with increased levels of STAT3, but not STAT5, phosphorylation in CD8+ cells from SHIV-infected RMs. In parallel, treatment with soluble IL-21R/Fc, an inhibitor of IL-21-induced activation of JAK1/3 and STAT3, abrogated IL-21-induced STAT3 activation and IFN-? production in CD8+ cells from SHIV-infected RMs in vitro. Our data indicated that IL-21 was a positive regulator of IFN-?-secreting CD8+ cells and increased the STAT3 phosphorylation, regulating T-cell immunity against acute SHIV infection in RMs. Our findings may provide a new basis for the development of immunotherapies for the control of SHIV/HIV infection.
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Characterization and ectopic expression of a populus hydroxyacid hydroxycinnamoyltransferase.
Mol Plant
PUBLISHED: 05-24-2013
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Cutinized and suberized cell walls in plants constitute physiologically important environment interfaces. They act as barriers limiting the loss of water and nutrients and protecting against radiation and invasion of pathogens. The roles of cutin- and suberin polyesters are often attributed to their dominant aliphatic components, but the contribution of aromatic composition to their physiological function remains unclear. By functionally screening a subset of Populus trichocarpa BAHD/HXXXD acyltransferases, we identified a hydroxycinnamoyltransferase that shows specific transacylation activity on ?-hydroxyacids using both feruloyl- and p-coumaroyl- CoA as the acyl donors. We named this enzyme P. trichocarpa hydroxyacid/fatty alcohol hydroxycinnamoyltransferase 1 (PtFHT1). The ectopic expression of the PtFHT1 gene in Arabidopsis increased the incorporation of ferulate in root and seed suberins and in leaf cutin, but not that of p-coumarate, while the aliphatic load in both suberin and cutin polyesters essentially remained unaffected. The overaccumulation of ferulate in lipophilic polyester significantly increased the tolerance of transgenic plants to salt stress treatment; under sub-lethal conditions of salt stress, the ratios of their seed germination and seedling establishment were 50% higher than those of wild-type plants. Our study suggests that, although aromatics are the minor component of polyesters, they play important role in the sealing function of lipidic polymers in planta.
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Effects of PGF2? on the expression of uterine activation proteins in pregnant human myometrial cells from upper and lower segment.
J. Clin. Endocrinol. Metab.
PUBLISHED: 05-15-2013
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The lower and upper segments of the uterus may play different roles in the process of parturition. The switch from pregnancy to delivery involves changes in expression of uterine activation proteins (UAPs). Prostaglandin (PG) F2? has multiple and complex roles in the birth process in addition to its vital contractile role.
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Effects of alendronate on the Notch1?RBP?J? signaling pathway in the osteogenic differentiation and mineralization of vascular smooth muscle cells.
Mol Med Rep
PUBLISHED: 04-03-2013
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Cardiovascular disease and osteoporosis are major causes of mortality in the elderly. Alendronate, a bisphosphonate, is widely used in the treatment of osteoporosis and may be used to inhibit vascular calcification. However, its mechanisms are not completely understood. The present study aimed to explore novel signaling mechanisms behind the action of alendronate in the osteoblastic differentiation of rat aortic vascular smooth muscle cells (VSMCs). The osteoblastic differentiation of VSMCs was induced by an osteogenic medium. Using von Kossa staining and direct cellular calcium content determination, mineralization was found to be significantly increased in VSMCs induced with osteogenic medium, consistent with an enhanced alkaline phosphatase activity. Osteoblastic differentiation in VSMCs was significantly reduced by the action of alendronate in a dose?dependent manner. In addition, the expression of Notch1 and RBP?J? was significantly upregulated in VSMCs cultured with osteogenic medium at the mRNA and protein levels. The effects of Notch1?RBP?J? were inhibited by treatment with alendronate in a dose?dependent manner. In summary, results of the current study indicate that alendronate inhibits vascular calcification through downregulation of the Notch1?RBP?J? signaling pathway.
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Pharmacodynamic effects of a D-amino acid oxidase inhibitor indicate a spinal site of action in rat models of neuropathic pain.
J. Pharmacol. Exp. Ther.
PUBLISHED: 03-21-2013
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Inhibition of d-amino acid oxidase (DAAO) activity is a potential target for the treatment of chronic pain. Here we characterized the effects of systemic administration of the DAAO inhibitor 4H-furo[3,2-b]pyrrole-5-carboxylic acid (SUN) in rat models of neuropathic and inflammatory pain. Oral administration of SUN dose dependently attenuated tactile allodynia induced by ligation of the L5 spinal nerve (SNL) and similarly reversed thermal hyperalgesia produced by chronic constriction injury. In addition, SUN was efficacious against complete Freunds adjuvant-induced thermal hyperalgesia. In these models, maximal reversal of pain-related behaviors corresponded with maximum rates of increase in brain and plasma d-serine concentrations, indicative of full inhibition of DAAO activity. To investigate the possible site(s) of action, we recorded spontaneous nerve activity and mechanically evoked responses of central spinal cord dorsal horn neurons and compared these with spontaneous activity of peripheral dorsal root filaments in anesthetized SNL model animals. Oral SUN reduced spontaneous activity in both central and peripheral recordings at doses and pretreatment times that corresponded to reduced mechanical allodynia in behavioral experiments. After intravenous administration of SUN, the onset of action for this central effect was rapid (maximal effects within 30 minutes), but was abolished by severing afferent inputs to the dorsal horn. Overall, these results indicate that inhibition of DAAO in peripheral afferent spinal circuits reduced spontaneous neuronal activity to attenuate pain-related behaviors in rat models of neuropathic and inflammatory pain.
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Integration of the second messenger c-di-GMP into the chemotactic signaling pathway.
MBio
PUBLISHED: 03-21-2013
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Elevated intracellular levels of the bacterial second messenger c-di-GMP are known to suppress motility and promote sessility. Bacterial chemotaxis guides motile cells in gradients of attractants and repellents over broad concentration ranges, thus allowing bacteria to quickly adapt to changes in their surroundings. Here, we describe a chemotaxis receptor that enhances, as opposed to suppresses, motility in response to temporary increases in intracellular c-di-GMP. Azospirillum brasilenses preferred metabolism is adapted to microaerophily, and these motile cells quickly navigate to zones of low oxygen concentration by aerotaxis. We observed that changes in oxygen concentration result in rapid changes in intracellular c-di-GMP levels. The aerotaxis and chemotaxis receptor, Tlp1, binds c-di-GMP via its C-terminal PilZ domain and promotes persistent motility by increasing swimming velocity and decreasing swimming reversal frequency, which helps A. brasilense reach low-oxygen zones. If c-di-GMP levels remain high for extended periods, A. brasilense forms nonmotile clumps or biofilms on abiotic surfaces. These results suggest that association of increased c-di-GMP levels with sessility is correct on a long-term scale, while in the short-term c-di-GMP may actually promote, as opposed to suppress, motility. Our data suggest that sensing c-di-GMP by Tlp1 functions similar to methylation-based adaptation. Numerous chemotaxis receptors contain C-terminal PilZ domains or other sensory domains, suggesting that intracellular c-di-GMP as well as additional stimuli can be used to modulate adaptation of bacterial chemotaxis receptors.
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Effect of Immune No. 2 on the immune reconstitution in patients with HIV/AIDS after highly active antiretroviral treatment: a randomized double blind placebo controlled clinical trial.
Chin J Integr Med
PUBLISHED: 03-15-2013
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To observe the Immune No. 2 (2) on the immune reconstitution in patients with human immunodeficiency virus or acquired immune deficiency syndrome (HIV/AIDS) after highly active antiretroviral therapy (HAART).
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Rational engineering of plasticity residues of sesquiterpene synthases from Artemisia annua: product specificity and catalytic efficiency.
Biochem. J.
PUBLISHED: 02-27-2013
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Most TPSs (terpene synthases) contain plasticity residues that are responsible for diversified terpene products and functional evolution, which provide a potential for improving catalytic efficiency. Artemisinin, a sesquiterpene lactone from Artemisia annua L., is widely used for malaria treatment and progress has been made in engineering the production of artemisinin or its precursors. In the present paper, we report a new sesquiterpene synthase from A. annua, AaBOS (A. annua ?-bisabolol synthase), which has high sequence identity with AaADS (A. annua amorpha-4,11-diene synthase), a key enzyme in artemisinin biosynthesis. Comparative analysis of the two enzymes by domain-swapping and structure-based mutagenesis led to the identification of several plasticity residues, whose alteration changed the product profile of AaBOS to include ?-humulene as the major product. To elucidate the underlying mechanisms, we solved the crystal structures of AaBOS and a ?-humulene-producing AaBOS mutant (termed AaBOS-M2). Among the plasticity residues, position 399, located in the substrate-binding pocket, is crucial for both enzymes. In AaBOS, substitution of threonine for leucine (AaBOSL339T) is required for ?-humulene production; whereas in AaADS, replacing the threonine residue with serine (AaADST399S) resulted in a substantial increase in the activity of amorpha-4,11-diene production, probably as a result of accelerated product release. The present study demonstrates that substitution of plasticity residues has potential for improving catalytic efficiency of the enzyme.
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Analysis for apoptosis and necrosis on adipocytes, stromal vascular fraction, and adipose-derived stem cells in human lipoaspirates after liposuction.
Plast. Reconstr. Surg.
PUBLISHED: 02-26-2013
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Adipose-derived stem cells have become the most studied adult stem cells. The authors examined the apoptosis and necrosis rates for adipocyte, stromal vascular fraction, and adipose-derived stem cells in fresh human lipoaspirates.
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c-di-GMP signaling regulates E. coli O157:H7 adhesion to colonic epithelium.
Vet. Microbiol.
PUBLISHED: 02-23-2013
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Escherichia coli O157:H7 is an important foodborne pathogen that causes serious illness in humans at low infectious doses. The main source of infections is beef or greens contaminated with E. coli O157:H7 shed by cattle. Here we investigated the role of c-di-GMP-dependent signal transduction in cattle gut colonization of E. coli O157:H7. To manipulate intracellular c-di-GMP levels, we introduced into E. coli O157:H7 a c-di-GMP specific phosphodiesterase (PDE). Liquid chromatography tandem mass spectrometry analysis confirmed that in E. coli O157:H7, over-expression of PDE decreased c-di-GMP level. Consistent with the altered c-di-GMP level, PDE overexpression resulted in decreased biofilm formation in E. coli O157:H7. Furthermore, this diminished c-di-GMP levels reduced adhesion of E. coli O157:H7 to both cultured HT-29 cells and cattle colon explants. Consistently, mRNA levels of genes involved in adhesion were down-regulated including genes encoding E. coli common pili, long polar fimbriae 1, hemorrhagic coli pilus, as well as intimin and tir. We further observed decreased curli fimbriae synthesis in the strain with decreased c-di-GMP levels, which was supported by the reduction in the transcription of curli large subunit gene csgA and the curli expression regulator gene csgD. Genes for enterocyte effacement encoded regulator (Ler) and type III secretion system effectors, EspA and EspB, were also down-regulated. Collectively, data indicated that c-di-GMP signaling positively regulates E. coli O157:H7 intestinal epithelial cell and tissue colonization and expression of associated adhesion factors.
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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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