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Find video protocols related to scientific articles indexed in Pubmed.
Pedicle screw piercer with warning device - A technique to increase accuracy of pedicle screw placement: A cadaveric study.
Indian J Orthop
PUBLISHED: 11-19-2014
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Pedicle screw fixation has achieved significant popularity amongst spinal surgeons for both single and multilevel spinal fusion. Suboptimal placements of pedicle screws may lead to neurological and vascular complications. There have been many advances in techniques available for navigating through the pedicle; however, these techniques are not without drawbacks. The purpose of this study was to investigate the efficacy and feasibility of the pedicle piercer with warning device.
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Aligned TiO2 nanotube/nanoparticle heterostructures with enhanced electrochemical performance as three-dimensional anode for lithium-ion microbatteries.
Nanotechnology
PUBLISHED: 10-22-2014
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A novel TiO2 three-dimensional (3D) anode with an aligned TiO2 nanotube/nanoparticle heterostructure (TiO2 NTs/NPs) is developed by simply immersing as-anodized TiO2 NTs into water and further crystallizing the TiO2 NTs by post-annealing. The heterostructure, with its core in a tubular morphology and with both the outer and inner surface consisting of nanoparticles, is confirmed by FESEM and TEM. A reversible areal capacity of 0.126 mAh · cm(-2) is retained after 50 cycles for the TiO2 NTs/NPs heterostructure electrode, which is higher than that of the TiO2 NTs electrode (0.102 mAh · cm(-2) after 50 cycles). At the current densities of 0.02, 0.04, 0.06, 0.08, 0.10 and 0.20 mA · cm(-2), the areal capacities are 0.142, 0.127, 0.117, 0.110, 0.104 and 0.089 mAh · cm(-2), respectively, for the TiO2 NTs/NPs heterostructure electrode compared to the areal capacities of 0.123, 0.112, 0.105, 0.101, 0.094 and 0.083 mAh · cm(-2), respectively, for the the TiO2 NTs electrode. The enhanced electrochemical performance is attributed to the unique microstructure of the TiO2 NTs/NPs heterostructure electrode with the TiO2 NT core used as a straight pathway for electronic transport and with TiO2 NP offering enhanced surface areas for facile Li+ insertion/extraction. The results described here inspire a facile approach to fabricate a 3D anode with an enhanced electrochemical performance for lithium-ion microbattery applications.
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[Evaluation and indication of human epithelial growth factor receptor 2 status in breast carcinoma with amplified chromosome].
Beijing Da Xue Xue Bao
PUBLISHED: 10-22-2014
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To study the evaluation of human epithelial growth factor receptor 2 (HER2) status in breast carcinoma with amplified chromosome 17 centromere locus (CEP17) and clinical significance of CEP17 amplification.
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[Effects of se-riched soybean peptide on antioxidant function in rats of fatty liver caused by high-fat diet].
Zhongguo Ying Yong Sheng Li Xue Za Zhi
PUBLISHED: 10-22-2014
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To explore the effect of Se-riched soybean peptide(SSP) on antioxidant function in rats of fatty liver caused by high-fat diet.
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Tacrolimus Versus Cyclosporine as Primary Immunosuppressant After Renal Transplantation: A Meta-Analysis and Economics Evaluation.
Am J Ther
PUBLISHED: 10-10-2014
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Tacrolimus and cyclosporine are the major immunosuppressants for renal transplantation. Several studies have compared these 2 drugs, but the outcomes were not consistent. The aim of this study was to evaluate the efficacy, safety, and pharmacoeconomics of cyclosporine and tacrolimus in the treatment of renal transplantation and provide evidence for the selection of essential drugs. Trials were identified through a computerized literature search of PubMed, EMBASE, Cochrane Controlled Trials Register, Cochrane Renal Group Specialized Register of randomized controlled trials, and Chinese Biomedical database. Two independent reviewers assessed trials for eligibility and quality and then extracted data. Data were extracted for patient and graft mortality, acute rejection, and adverse events. Dichotomous outcomes were reported as relative risk with 95% confidence intervals. A decision tree model was populated with data from a literature review and used to estimate costs and quality-adjusted life years gained and incremental cost-effectiveness. Altogether, 6137 patients from 27 randomized controlled trials were included. The results of our analysis were that tacrolimus reduced the risks after renal transplantation of patient mortality, graft loss, acute rejection, and hypercholesterolemia. Nevertheless, tacrolimus increased the risk of new-onset diabetes. Pharmacoeconomic analysis showed that tacrolimus represented a more cost-effective treatment than does cyclosporine for the prevention of adverse events following renal transplant. Tacrolimus is an effective and safe immunosuppressive agent and it may be more cost-effective than cyclosporine for the primary prevention of graft rejection in renal transplant recipients. However, new-onset diabetes should be closely monitored during the medication period.
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Orbital Kondo effect in a parallel double quantum dot.
J Phys Condens Matter
PUBLISHED: 10-09-2014
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We construct a theoretical model to study the orbital Kondo effect in a parallel double quantum dot (DQD). Recently, pseudospin-resolved transport spectroscopy of the orbital Kondo effect in a DQD has been experimentally reported. The experiment revealed that when interdot tunneling is ignored, two and one Kondo peaks exist in the conductance-bias curve for pseudospin-non-resolved and pseudospin-resolved cases, respectively. Our theoretical studies reproduce this experimental result. We also investigate the case of all lead voltages being non-equal (the complete pseudospin-resolved case) and found that there are at most four Kondo peaks in the curve of the conductance versus the pseudospin splitting energy. When interdot tunneling is introduced, some new Kondo peaks and dips can emerge. Furthermore, the pseudospin transport and the pseudospin flipping current are also studied in the DQD system. Since the pseudospin transport is much easier to control and measure than the real spin transport, it can be used to study the physical phenomenon related to the spin transport.
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IL28B genetic variations are associated with treatment response of patients with chronic hepatitis C in Chinese Han population.
J Dig Dis
PUBLISHED: 09-30-2014
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This study aimed to investigate the association of interleukin 28B (IL28B) single nucleotide polymorphisms (SNPs) with sustained response (SVR) in Chinese Han patients with chronic hepatitis C (CHC) and to analysz the correlations between IL28B SNPs and their demographic, virological and clinical characteristics.
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A strategy to reduce the angular dependence of a dye-sensitized solar cell by coupling to a TiO2 nanotube photonic crystal.
Nanoscale
PUBLISHED: 09-24-2014
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Almost all types of solar cells suffer from a decreased power output when the incident light is tilted away from normal since the incident intensity generally follows a cosine law of the incident angle. Making use of the blue shift nature of the Bragg position of a TiO2 nanotube photonic crystal (NT PC) under oblique incidence, we demonstrate experimentally that the use of the NT PC can partially compensate the cosine power loss of a dye-sensitized solar cell (DSSC). The strategy used here is to purposely choose the Bragg position of the NT PC to be at the longer wavelength side of the dye absorption peak. When the incident light is tilted, the blue shift of the Bragg position results in more overlap with the dye absorption peak, generating a higher efficiency that partially compensates the reduced photon flux due to light inclination. Moreover, the unique structure of the vertically aligned TiO2 nanotubes contributes an additional scattering effect when the incident light is tilted. As a result, the power output of a DSSC coupled with the NT PC layer shows a much flatter angular dependence than a DSSC without the NT PC. At all the incident angles, the DSSC coupled with the NT PC layer also shows a higher power conversion efficiency than the one without. The concept of using NT PC to mitigate the angular dependence of DSSCs can be easily extended to many other optoelectronic devices that are irradiance sensitive.
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[Analysis of metabolic risk factors for developing nonalcoholic fatty liver in patients with type 2 diabetes mellitus].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 09-23-2014
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To compare and explore metabolic risk factors related to type 2 diabetes mellitus (T2DM) and the development of nonalcoholic fatty liver disease (NAFLD).
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Stable 4 V-class bicontinuous cathodes by hierarchically porous carbon coating on Li3V2(PO4)3 nanospheres.
Nanoscale
PUBLISHED: 09-20-2014
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A high performance, durable cathode material for lithium ion batteries is achieved by incorporating ?50 nm Li3V2(PO4)3/C core-shell nanospheres into a porous carbon framework. The Li3V2(PO4)3/C nanocomposite delivers an initial discharge capacity of 130 mA h g(-1), approaching its theoretical limit (133 mA h g(-1)). At a high current rate (10 C), the nanocomposite displays an impressive long cycle life and remarkable capacity retention (90% after 1200 cycles). Notably, the Coulombic efficiency is above 99% during the course of cycling. The remarkable power capability and cycle stability derived from our simple and scalable synthesis suggests that this 4 V-class material could be one of the most promising candidates for future batteries.
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Cis-12-oxo-phytodienoic Acid stimulates rice defense response to a piercing-sucking insect.
Mol Plant
PUBLISHED: 09-19-2014
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The brown planthopper (BPH, Nilaparvata lugens) is a destructive, monophagous, piercing-sucking insect pest of rice. Previous studies indicated that jasmonic acid (JA) positively regulates rice defense against chewing insect pests but negatively regulates it against the piercing-sucking insect of BPH. We here demonstrated that overexpression of allene oxide cyclase (AOC) but not OPR3 (cis-12-oxo-phytodienoic acid (OPDA) reductase 3, an enzyme adjacent to AOC in the JA synthetic pathway) significantly increased rice resistance to BPH, mainly by reducing the feeding activity and survival rate. Further analysis revealed that plant response to BPH under AOC overexpression was independent of the JA pathway and that significantly higher OPDA levels stimulated rice resistance to BPH. Microarray analysis identified multiple candidate resistance-related genes under AOC overexpression. OPDA treatment stimulated the resistance of radish seedlings to green peach aphid Myzus persicae, another piercing-sucking insect. These results imply that rice resistance to chewing insects and to sucking insects can be enhanced simultaneously through AOC-mediated increases of JA and OPDA and provide direct evidence of the potential application of OPDA in stimulating plant defense responses to piercing-sucking insect pests in agriculture.
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Relationship Between Alcohol Consumption and Serum Lipid Profiles Among Middle-Aged Population in China: A Multiple-Center Cardiovascular Epidemiological Study.
Angiology
PUBLISHED: 09-04-2014
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We assessed the relationship between alcohol consumption and serum lipids in a middle-aged Chinese population. The overall prevalence of drinking among 10 154 participants was 34.07% in males and 3.61% in females. Heavy alcohol drinkers (? 30 g/d) tended to be older, smokers, hypertensive, do heavy physical activity, and have a lower body mass index. Levels of high-density lipoprotein cholesterol (HDL-C), apolipoprotein (apo) A1, low-density lipoprotein cholesterol-HDL-C ratio, and apo B-apo A1 ratio rose with increase in alcohol intake in males. An increase of 0.27 mmol/L in triglycerides and a decrease of 2.10 mg/dL in lipoprotein(a), Lp(a), were observed in male alcohol drinkers who consumed ?30 g alcohol/d compared with abstainers after controlling for all confounders. Levels of total cholesterol, HDL-C, and apo A1 increased with increase in alcohol intake in both genders and Lp(a) decreased with the increase in alcohol intake in males.
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Sodium fluoride induces apoptosis in the kidney of rats through caspase-mediated pathways and DNA damage.
J. Physiol. Biochem.
PUBLISHED: 08-27-2014
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Long-term excessive sodium fluoride (NaF) intake can cause many bone diseases and nonskeletal fluorosis. The kidneys are the primary organs involved in the excretion and retention of NaF. The objective of the present study was to determine the effects of NaF treatment on renal cell apoptosis, DNA damage, and the protein expression levels of cytosolic cytochrome C (Cyt C) and cleaved caspases 9, 8, and 3 in vivo. Male Sprague-Dawley rats were divided randomly into four groups (control, low fluoride, medium fluoride, and high fluoride) and administered 0, 50, 100, and 200 mg/L of NaF, respectively, via drinking water for 120 days. Histopathological changes in the kidneys were visualized using hematoxylin and eosin staining. Renal cell apoptosis was examined using flow cytometry, and renal cell DNA damage was detected using the comet assay. Cytosolic Cyt C and cleaved caspases 9, 8, and 3 protein expression levels were visualized using immunohistochemistry and Western blotting. The results showed that NaF treatment increased apoptosis and DNA damage. In addition, NaF treatment increased the protein expression levels of cytosolic Cyt C and cleaved caspases 9, 8, and 3. These results indicated that NaF induces apoptosis in the kidney of rats through caspase-mediated pathway, and DNA damage may be involved in this process.
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Persistent hepatitis C virus infections and hepatopathological manifestations in immune-competent humanized mice.
Cell Res.
PUBLISHED: 08-26-2014
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The majority of hepatitis C virus (HCV) infection develops chronic infection, which causes steatosis, cirrhosis and hepatocellular carcinoma. However, understanding HCV chronicity and pathogenesis is hampered by its narrow host range, mostly restricted to human and chimpanzee. Recent endeavour to infect a variety of humanized mice has not been able to achieve persistent HCV infection unless the essential innate immune responsive genes are knocked out. Nevertheless, such immune-compromised humanized mice still lacked HCV infection-induced hepatopathogenesis. Here we report that transgenic mice in ICR background harboring both human CD81 and occludin genes (C/O(Tg)) are permissive to HCV infection at a chronicity rate comparable to humans. In this mouse model, HCV accomplishes its replication cycle, leading to sustained viremia and infectivity for more than 12 months post infection with expected fibrotic and cirrhotic progression. Host factors favorable for HCV replication, and inadequate innate immune-response may contribute to the persistence. Lastly, NS3/4 protease inhibitor telaprevir can effectively inhibit de novo RNA synthesis and acute HCV infection of C/O(Tg) mice. Thus, chronic HCV infection with complete replication cycle and hepatopathologic manifestations is recapitulated, for the first time, in immune-competent mice. This model will open a new venue to study the mechanisms of chronic hepatitis C and develop better treatments.
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A comparative study on the levels of serum cytokines and cortisol among post-traumatic stress disorder patients of Li and Han ethnicities in Hainan.
Chin. Med. J.
PUBLISHED: 08-23-2014
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Post-traumatic stress disorder (PTSD) is a mental disorder with delayed or chronic onset caused by unusual, threatening, or disastrous psychological trauma, and it is an important manifestation of post-disaster mental and behavioral disorders. Studies have shown that IL-6 is a cytokine associated with PTSD occurrence. This study aimed to explore the role of cytokine and ethnicity in the pathogenesis of PTSD by examining levels of serum cytokines IL-2, IL-6, IL-8, TNF-?, and cortisol in PTSD patients of Li and Han ethnic groups.
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Feasible conversion of solid waste bauxite tailings into highly crystalline 4A zeolite with valuable application.
Waste Manag
PUBLISHED: 08-18-2014
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Bauxite tailings are a major type of solid wastes generated in the flotation process. The waste by-products caused significant environmental impact. To lessen this hazardous effect from poisonous mine tailings, a feasible and cost-effective solution was conceived and implemented. Our approach focused on reutilization of the bauxite tailings by converting it to 4A zeolite for reuse in diverse applications. Three steps were involved in the bauxite conversion: wet-chemistry, alkali fusion, and crystallization to remove impurities and to prepare porous 4A zeolite. It was found that the cubic 4A zeolite was single phase, in high purity, with high crystallinity and well-defined structure. Importantly, the 4A zeolite displayed maximum calcium ion exchange capacity averaged at 296mg CaCO3/g, comparable to commercially-available zeolite (310mg CaCO3/g) exchange capacity. Base on the optimal synthesis condition, the reaction yield of zeolite 4A from bauxite tailings achieved to about 38.43%, hence, this study will provide a new paradigm for remediation of bauxite tailings, further mitigating the environmental and health care concerns, particularly in the mainland of PR China.
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Methane-oxygen electrochemical coupling in an ionic liquid: a robust sensor for simultaneous quantification.
Analyst
PUBLISHED: 08-05-2014
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Current sensor devices for the detection of methane or natural gas emission are either expensive and have high power requirements or fail to provide a rapid response. This report describes an electrochemical methane sensor utilizing a non-volatile and conductive pyrrolidinium-based ionic liquid (IL) electrolyte and an innovative internal standard method for methane and oxygen dual-gas detection with high sensitivity, selectivity, and stability. At a platinum electrode in bis(trifluoromethylsulfonyl)imide (NTf2)-based ILs, methane is electro-oxidized to produce CO2 and water when an oxygen reduction process is included. The in situ generated CO2 arising from methane oxidation was shown to provide an excellent internal standard for quantification of the electrochemical oxygen sensor signal. The simultaneous quantification of both methane and oxygen in real time strengthens the reliability of the measurements by cross-validation of two ambient gases occurring within a single sample matrix and allows for the elimination of several types of random and systematic errors in the detection. We have also validated this IL-based methane sensor employing both conventional solid macroelectrodes and flexible microfabricated electrodes using single- and double-potential step chronoamperometry.
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Spin-dependent electron transport in protein-like single-helical molecules.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-28-2014
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We report on a theoretical study of spin-dependent electron transport through single-helical molecules connected by two nonmagnetic electrodes, and explain the experiment of significant spin-selective phenomenon observed in ?-helical protein and the contradictory results between the protein and single-stranded DNA. Our results reveal that the ?-helical protein is an efficient spin filter and the spin polarization is robust against the disorder. These results are in excellent agreement with recent experiments [Mishra D, et al. (2013) Proc Natl Acad Sci USA 110(37):14872-14876; Göhler B, et al. (2011) Science 331(6019):894-897] and may facilitate engineering of chiral-based spintronic devices.
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[Variation characteristic in soil respiration of apple orchard and its biotic and abiotic influencing factors].
Huan Jing Ke Xue
PUBLISHED: 07-25-2014
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To evaluate the orchard variability of soil respiration and the response of soil respiration to its influencing factors is helpful for a deep understanding about the effects of converting cropland to apple orchard. A field experiment was conducted in the Changwu State Key Agro-Ecological Station. Soil respiration, soil temperature, soil moisture and roots biomasses were periodically measured in a mature apple orchard during 2011 and 2012. Soil respiration decreased as the distance from the trunk increased. The cumulative soil respiration in the 0.5 m-distance from the trunk was 20% and 31% higher than that in the 2 m-distance from the trunk, respectively in 2011 and 2012. The temperature sensitivity of soil respiration (Q10) was relatively lower in the 2 m-distance than that in the 0. 5 m-distance in both years. Soil temperature and soil moisture were slightly higher in the 2 m-distance, but there was no significant difference between the 2 m-distance and the 0. 5 m-distance. Soil respiration and soil temperature showed a significant exponential relationship, but there was no positive correlation between soil moisture and soil respiration. Soil temperature changes can explain seasonal variation of soil respiration well, but it could not explain its spatial variability. Root density was an important factor for the spatial variability of soil respiration and Q15. Variation of soil respiration coefficient was 23% -31%. Therefore, the distance from the trunk should be considered when estimating orchards soil respiration.
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Large-diameter titanium dioxide nanotube arrays as a scattering layer for high-efficiency dye-sensitized solar cell.
Nanoscale Res Lett
PUBLISHED: 07-20-2014
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Large-sized titanium dioxide (TiO2) nanotube arrays with an outer diameter of approximately 500 nm have been successfully synthesized by potentiostatic anodization at 180 V in a used electrolyte with the addition of 1.5 M lactic acid. It is found that the synthesized large-diameter TiO2 nanotube array shows a superior light scattering ability, which can be used as a light scattering layer to significantly enhance the efficiency of TiO2 nanoparticle-based dye-sensitized solar cells from 5.18% to 6.15%. The remarkable light scattering ability makes the large-diameter TiO2 nanotube array a promising candidate for light management in dye-sensitized solar cells (DSSCs).
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Human tRNA synthetase catalytic nulls with diverse functions.
Science
PUBLISHED: 07-19-2014
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Genetic efficiency in higher organisms depends on mechanisms to create multiple functions from single genes. To investigate this question for an enzyme family, we chose aminoacyl tRNA synthetases (AARSs). They are exceptional in their progressive and accretive proliferation of noncatalytic domains as the Tree of Life is ascended. Here we report discovery of a large number of natural catalytic nulls (CNs) for each human AARS. Splicing events retain noncatalytic domains while ablating the catalytic domain to create CNs with diverse functions. Each synthetase is converted into several new signaling proteins with biological activities "orthogonal" to that of the catalytic parent. We suggest that splice variants with nonenzymatic functions may be more general, as evidenced by recent findings of other catalytically inactive splice-variant enzymes.
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HBV preS2 transactivates FOXP3 expression in malignant hepatocytes.
Liver Int.
PUBLISHED: 07-11-2014
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Recent data reported the increased expression of forkhead box protein 3 (FOXP3), the well known master regulator of CD4(+) C25(+) regulatory T cells, in hepatocellular carcinoma (HCC) cells. However, the mechanisms remain unknown. We previously showed that preS2, one of important regulatory proteins encoded by HBV, triggers transactivation of hTERT in malignant hepatocytes. Here, we aimed to explore the role of preS2 in regulating FOXP3 expression in HCC.
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[Current prevalence rates of overweight, obesity, central obesity, and related cardiovascular risk factors that clustered among middle-aged population of China].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 07-11-2014
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To analyze the current prevalence rates of overweight, obesity, central obesity and the clustering of major cardiovascular risks among middle-aged population of China.
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Risk factors for depth of infiltration in the differentiated depressed early gastric carcinoma: a preliminary analysis.
Diagn Pathol
PUBLISHED: 05-26-2014
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To analyze the clinicopathologic factors associated with mucosal and submucosal infiltration in differentiated depressed early gastric cancer, and screening factors that can predict depth of infiltration before endoscopic treatment.
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Metformin may produce antidepressant effects through improvement of cognitive function among depressed patients with diabetes mellitus.
Clin. Exp. Pharmacol. Physiol.
PUBLISHED: 05-13-2014
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Diabetes mellitus and depressive disorders are both common chronic diseases that increase functional disability and social burden. Cognitive impairment is a potentially debilitating feature of depression. Previous evidence indicates that the antidiabetic drug metformin could be suitable for diabetic patients with cognitive impairment. However, there is no direct evidence from clinical studies that metformin treatment improves cognitive function in diabetic patients suffering from depression. In the present study, 58 participants diagnosed with depression and type 2 diabetes mellitus (T2DM) were recruited and divided into two groups, one treated with metformin and the other treated with placebo for 24 weeks. Cognitive function, depressive behaviour and diabetes improvement were evaluated. Chronic treatment with metformin for 24 weeks improved cognitive performance, as assessed by the Wechsler Memory Scale-Revised, in depressed patients with T2DM. In addition, metformin significantly improved depressive performance and changed the glucose metabolism in depressed patients with diabetes. Depressive symptoms were negatively correlated with cognitive performance in metformin-treated participants. Furthermore, associations were observed between the parameters of blood glucose metabolism and the depression phenotype. These findings suggest that chronic treatment with metformin has antidepressant behavioural effects and that improved cognitive function is involved in the therapeutic outcome of metformin. The results of the present study also raise the possibility that supplementary administration of antidiabetic medications may enhance the recovery of depression, comorbid with T2DM, through improvements in cognitive performance.
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Aperiodic TiO2 nanotube photonic crystal: full-visible-spectrum solar light harvesting in photovoltaic devices.
Sci Rep
PUBLISHED: 05-09-2014
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Bandgap engineering of a photonic crystal is highly desirable for photon management in photonic sensors and devices. Aperiodic photonic crystals (APCs) can provide unprecedented opportunities for much more versatile photon management, due to increased degrees of freedom in the design and the unique properties brought about by the aperiodic structures as compared to their periodic counterparts. However, many efforts still remain on conceptual approaches, practical achievements in APCs are rarely reported due to the difficulties in fabrication. Here, we report a simple but highly controllable current-pulse anodization process to design and fabricate TiO2 nanotube APCs. By coupling an APC into the photoanode of a dye-sensitized solar cell, we demonstrate the concept of using APC to achieve nearly full-visible-spectrum light harvesting, as evidenced by both experimental and simulated results. It is anticipated that this work will lead to more fruitful practical applications of APCs in high-efficiency photovoltaics, sensors and optoelectronic devices.
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A study of force distribution of loading stresses on implant-bone interface on short implant length using 3-dimensional finite element analysis.
Oral Surg Oral Med Oral Pathol Oral Radiol
PUBLISHED: 03-21-2014
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The purpose of this study is to evaluate the biomechanics of short dental implants.
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Nitrate removal by Fe0/Pd/Cu nano-composite in groundwater.
Environ Technol
PUBLISHED: 03-21-2014
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Nitrate pollution in groundwater shows a great threat to the safety of drinking water. Chemical reduction by zero-valent iron is being considered as a promising technique for nitrate removal from contaminated groundwater. In this paper, Fe0/Pd/Cu nano-composites were prepared by the liquid-phase reduction method, and batch experiments of nitrate reduction by the prepared Fe0/Pd/Cu nano-composites under various operating conditions were carried out. It has been found that nano-Fe0/Pd/Cu composites processed dual functions: catalytic reduction and chemical reduction. The introduction of Pd and Cu not only improved nitrate removal rate, but also reduced the generation of ammonia. Nitrate removal rate was affected by the amount of Fe0/Pd/Cu, initial nitrate concentration, solution pH, dissolved oxygen (DO), reaction temperature, the presence of anions, and organic pollutant. Moreover, nitrate reduction by Fe0/Pd/Cu composites followed the pseudo-first-order reaction kinetics. The removal rate of nitrate and total nitrogen were about 85% and 40.8%, respectively, under the reaction condition of Fe-6.0%Pd-3.0%Cu amount of 0.25 g/L, pH value of 7.1, DO of 0.42 mg/L, and initial nitrate concentration of 100 mg/L. Compared with the previous studies with Fe0 alone or Fe-Cu, nano-Fe-6%Pd-3%Cu composites showed a better selectivity to N2.
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Activation of AMPK and inactivation of Akt result in suppression of mTOR-mediated S6K1 and 4E-BP1 pathways leading to neuronal cell death in in vitro models of Parkinson's disease.
Cell. Signal.
PUBLISHED: 03-17-2014
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Parkinson's disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons. Dysregulation of mammalian target of rapamycin (mTOR) has been implicated in the pathogenesis of PD. However, the underlying mechanism is incompletely elucidated. Here, we show that PD mimetics (6-hydroxydopamine, N-methyl-4-phenylpyridine or rotenone) suppressed phosphorylation of mTOR, S6K1 and 4E-BP1, reduced cell viability, and activated caspase-3 and PARP in PC12 cells and primary neurons. Overexpression of wild-type mTOR or constitutively active S6K1, or downregulation of 4E-BP1 in PC12 cells partially prevented cell death in response to the PD toxins, revealing that mTOR-mediated S6K1 and 4E-BP1 pathways due to the PD toxins were inhibited, leading to neuronal cell death. Furthermore, we found that the inhibition of mTOR signaling contributing to neuronal cell death was attributed to suppression of Akt and activation of AMPK. This is supported by the findings that ectopic expression of constitutively active Akt or dominant negative AMPK?, or inhibition of AMPK? with compound C partially attenuated inhibition of phosphorylation of mTOR, S6K1 and 4E-BP1, activation of caspase-3, and neuronal cell death triggered by the PD toxins. The results indicate that PD stresses activate AMPK and inactivate Akt, causing neuronal cell death via inhibiting mTOR-mediated S6K1 and 4E-BP1 pathways. Our findings suggest that proper co-manipulation of AMPK/Akt/mTOR signaling may be a potential strategy for prevention and treatment of PD.
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Identification and comparative analysis of the major chemical constituents in the extracts of single fuzi herb and fuzi-gancao herb-pair by UFLC-IT-TOF/MS.
Chin J Nat Med
PUBLISHED: 02-20-2014
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The aim of this work was to establish a specific and sensitive method to comprehensively investigate and compare chemical constituents of Fuzi-Gancao herb pair (FG), consisting of Aconitum carmichaelii Debeaux (Fuzi, Chinese) and Roast Radix Glycyrrhizae (Glycyrrhiza glabra L., Gancao, in Chinese) and Fuzi alone to explore the underlying interaction mechanism of FG.
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Environmental and Psycho-social Factors Related to Prostate Cancer Risk in the Chinese Population: a Case-control Study.
Biomed. Environ. Sci.
PUBLISHED: 02-18-2014
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To study the risk environmental and psycho-social factors associated to prostate cancer (PCa) in Chinese population.
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The MafA transcription factor becomes essential to islet ?-cells soon after birth.
Diabetes
PUBLISHED: 02-11-2014
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The large Maf transcription factors, MafA and MafB, are expressed with distinct spatial-temporal patterns in rodent islet cells. Analysis of Mafa(-/-) and pancreas-specific Mafa(?panc) deletion mutant mice demonstrated a primary role for MafA in adult ?-cell activity, different from the embryonic importance of MafB. Our interests here were to precisely define when MafA became functionally significant to ?-cells, to determine how this was affected by the brief period of postnatal MafB production, and to identify genes regulated by MafA during this period. We found that islet cell organization, ?-cell mass, and ?-cell function were influenced by 3 weeks of age in Mafa(?panc) mice and compromised earlier in Mafa(?panc);Mafb(+/-) mice. A combination of genome-wide microarray profiling, electron microscopy, and metabolic assays were used to reveal mechanisms of MafA control. For example, ?-cell replication was produced by actions on cyclin D2 regulation, while effects on granule docking affected first-phase insulin secretion. Moreover, notable differences in the genes regulated by embryonic MafB and postnatal MafA gene expression were found. These results not only clearly define why MafA is an essential transcriptional regulator of islet ?-cells, but also why cell maturation involves coordinated actions with MafB.
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The selective tRNA aminoacylation mechanism based on a single G•U pair.
Nature
PUBLISHED: 02-07-2014
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Ligation of tRNAs with their cognate amino acids, by aminoacyl-tRNA synthetases, establishes the genetic code. Throughout evolution, tRNA(Ala) selection by alanyl-tRNA synthetase (AlaRS) has depended predominantly on a single wobble base pair in the acceptor stem, G3•U70, mainly on the kcat level. Here we report the crystal structures of an archaeal AlaRS in complex with tRNA(Ala) with G3•U70 and its A3•U70 variant. AlaRS interacts with both the minor- and the major-groove sides of G3•U70, widening the major groove. The geometry difference between G3•U70 and A3•U70 is transmitted along the acceptor stem to the 3'-CCA region. Thus, the 3'-CCA region of tRNA(Ala) with G3•U70 is oriented to the reactive route that reaches the active site, whereas that of the A3•U70 variant is folded back into the non-reactive route. This novel mechanism enables the single wobble pair to dominantly determine the specificity of tRNA selection, by an approximate 100-fold difference in kcat.
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Vaccination with a HSV-2 UL24 mutant induces a protective immune response in murine and guinea pig vaginal infection models.
Vaccine
PUBLISHED: 01-24-2014
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The rational design and development of genetically attenuated HSV-2 mutant viruses represent an attractive approach for developing both prophylactic and therapeutic vaccines for genital herpes. Previously, HSV-2 UL24 was shown to be a virulence determinant in both murine and guinea pig vaginal infection models. An UL24-?gluc insertion mutant produced syncytial plaques and replicated to nearly wild type levels in tissue culture, but induced little or no pathological effects in recipient mice or guinea pigs following vaginal infection. Here we report that immunization of mice or guinea pigs with high or low doses of UL24-?gluc elicited a highly protective immune response. UL24-?gluc immunization via the vaginal or intramuscular routes was demonstrated to protect mice from a lethal vaginal challenge with wild type HSV-2. Moreover, antigen re-stimulated splenic lymphocytes harvested from immunized mice exhibited both HSV-2 specific CTL activity and IFN-? expression. Humoral anti-HSV-2 responses in serum were Th1-polarized (IgG2a>IgG1) and contained high-titer anti-HSV-2 neutralizing activity. Guinea pigs vaccinated subcutaneously with UL24-?gluc or the more virulent parental strain (186) were challenged with a heterologous HSV-2 strain (MS). Acute disease scores were nearly indistinguishable in guinea pigs immunized with either virus. Recurrent disease scores were reduced in UL24-?gluc immunized animals but not to the same extent as those immunized with strain 186. In addition, challenge virus was not detected in 75% of guinea pigs subcutaneously immunized with UL24-?gluc. In conclusion, disruption of the UL24 gene is a prime target for the development of a genetically attenuated live HSV-2 vaccine.
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Endoscopic submucosal dissection vs endoscopic mucosal resection for superficial esophageal cancer.
World J. Gastroenterol.
PUBLISHED: 01-19-2014
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To investigate the effectiveness of endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) in treating superficial esophageal cancer (SEC).
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Characteristics of selected indoor air pollutants from moxibustion.
J. Hazard. Mater.
PUBLISHED: 01-16-2014
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Concentrations and risk of monoaromatic hydrocarbons (MAHC), formaldehyde (HCHO), and polycyclic aromatic hydrocarbons (PAHs) in two moxibustion rooms were determined. The mean concentrations of MAHC, HCHO and PAHs were 535.2 ?g/m(3), 157.9 ?g/m(3) and 12.86?g/m(3), respectively, with notable health risks, indicating relatively serious pollution in indoor air due to the use of burning moxa. The indoor emissions of target pollutants from burning moxa in test chamber were also investigated. Toluene, benzene and xylene appeared to be dominant MAHCs, and naphthalene (NA) the dominant PAH, which were consistent with the pollution levels of the detected moxibustion rooms. The emission characteristics of smoky moxa and mild moxa were much in common and relatively close to that of tobacco; while that of smoke-free moxa showed a distinction. Though pollutants emission patterns varied within the three types of moxa, all of them had apparently higher emission intensities than other typical indoor sources, including tobacco. The results of this study can offer some references during the selection of moxa sticks and application of moxibustion.
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Pleiotropic function of the putative zinc-finger protein MoMsn2 in Magnaporthe oryzae.
Mol. Plant Microbe Interact.
PUBLISHED: 01-11-2014
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The mitogen-activated protein kinase MoOsm1-mediated osmoregulation pathway plays crucial roles in stress responses, asexual and sexual development, and pathogenicity in Magnaporthe oryzae. Utilizing an affinity purification approach, we identified the putative transcriptional activator MoMsn2 as a protein that interacts with MoOsm1 in vivo. Disruption of the MoMSN2 gene resulted in defects in aerial hyphal growth, conidial production, and infection of host plants. Quantitative reverse transcription-polymerase chain reaction analysis showed that the expression of several genes involved in conidiophore formation was reduced in ?Momsn2, suggesting that MoMsn2 might function as a transcriptional regulator of these genes. Subsequently, MoCos1 was identified as one of the MoMsn2 targets through yeast one-hybrid analysis in which MoMsn2 binds to the AGGGG and CCCCT motif of the MoCOS1 promoter region. Phenotypic characterization showed that MoMsn2 was required for appressorium formation and penetration and pathogenicity. Although the ?Momsn2 mutant was tolerant to the cell-wall stressor Calcofluor white, it was sensitive to common osmotic stressors. Further analysis suggests that MoMsn2 is involved in the regulation of the cell-wall biosynthesis pathway. Finally, transcriptome data revealed that MoMsn2 modulates numerous genes participating in conidiation, infection, cell-wall integrity, and stress response. Collectively, our results led to a model in which MoMsn2 mediates a series of downstream genes that control aerial hyphal growth, conidiogenesis, appressorium formation, cell-wall biosynthesis, and infection and that also offer potential targets for the development of new disease management strategies.
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Nonlinear dual reconstruction of SPECT activity and attenuation images.
PLoS ONE
PUBLISHED: 01-01-2014
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In single photon emission computed tomography (SPECT), accurate attenuation maps are needed to perform essential attenuation compensation for high quality radioactivity estimation. Formulating the SPECT activity and attenuation reconstruction tasks as coupled signal estimation and system parameter identification problems, where the activity distribution and the attenuation parameter are treated as random variables with known prior statistics, we present a nonlinear dual reconstruction scheme based on the unscented Kalman filtering (UKF) principles. In this effort, the dynamic changes of the organ radioactivity distribution are described through state space evolution equations, while the photon-counting SPECT projection data are measured through the observation equations. Activity distribution is then estimated with sub-optimal fixed attenuation parameters, followed by attenuation map reconstruction given these activity estimates. Such coupled estimation processes are iteratively repeated as necessary until convergence. The results obtained from Monte Carlo simulated data, physical phantom, and real SPECT scans demonstrate the improved performance of the proposed method both from visual inspection of the images and a quantitative evaluation, compared to the widely used EM-ML algorithms. The dual estimation framework has the potential to be useful for estimating the attenuation map from emission data only and thus benefit the radioactivity reconstruction.
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Immunoregulation effect of crude extract of C. elegans on allergic asthma.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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To explore effects of natural crude extract of C. elegans on treatment of asthma.
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Genomic evolution of 11 type strains within family Planctomycetaceae.
PLoS ONE
PUBLISHED: 01-01-2014
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The species in family Planctomycetaceae are ideal groups for investigating the origin of eukaryotes. Their cells are divided by a lipidic intracytoplasmic membrane and they share a number of eukaryote-like molecular characteristics. However, their genomic structures, potential abilities, and evolutionary status are still unknown. In this study, we searched for common protein families and a core genome/pan genome based on 11 sequenced species in family Planctomycetaceae. Then, we constructed phylogenetic tree based on their 832 common protein families. We also annotated the 11 genomes using the Clusters of Orthologous Groups database. Moreover, we predicted and reconstructed their core/pan metabolic pathways using the KEGG (Kyoto Encyclopedia of Genes and Genomes) orthology system. Subsequently, we identified genomic islands (GIs) and structural variations (SVs) among the five complete genomes and we specifically investigated the integration of two Planctomycetaceae plasmids in all 11 genomes. The results indicate that Planctomycetaceae species share diverse genomic variations and unique genomic characteristics, as well as have huge potential for human applications.
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[Prevalence of nutritional risk among in-patients with liver diseases in Beijing, China].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 12-17-2013
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To investigate the prevalence of nutritional risk and malnutrition among in-patients with liver diseases in Beijing, China, and to evaluate the relationship between nutritional risk and prognosis.
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Enhanced light harvesting in dye-sensitized solar cells coupled with titania nanotube photonic crystals: a theoretical study.
ACS Appl Mater Interfaces
PUBLISHED: 12-13-2013
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Herein we present a theoretical analysis on the optical properties and the photocurrent enhancement of nanotube-based dye-sensitized solar cells (DSSCs) coupled with a TiO2 nanotube (NT) photonic crystal (PC). It is found that the introduction of a TiO2 nanotube PC produces both Bragg mirror effect and Fabry-Perot cavity behavior, leading to a significant enhancement of light harvesting for photons in the photonic bandgap and at the two band edges. In addition, an increased amount of surface-anchored dye due to the larger surface area in the NT PC layer also causes absorption enhancement in the whole visible spectrum. The effects of structural parameters of the PC, such as the thickness of the PC layer, the axial lattice constant, the diameter of the nanotube, and light incident angle, on the optical properties and photocurrent magnification are thoroughly studied. The optimum structural parameters are proposed, which not only provide guidance but also offer further opportunities in the design and applications of TiO2 nanotube photonic crystals.
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Prevalence of Microalbuminuria Among Middle-Aged Population of China: A Multiple Center Cardiovascular Epidemiological Study.
Angiology
PUBLISHED: 12-05-2013
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We assessed the prevalence of microalbuminuria (MAU) and the relationships with other cardiovascular (CV) risk factors among a middle-aged Chinese population. Data from 10 313 participants were included in our cross-sectional survey. Microalbuminuria was defined as the urine albumin to creatinine ratio of 30:300 mg/g from a single-spot morning urine sample. Microalbuminuria was found to be common in males and females (15.04% vs 10.09%) aged 35 to 64 years in this Chinese general population, especially in those with obesity, hypertension, and diabetes. Multivariate analysis found that body mass index, triglyceride, high-sensitivity C-reactive protein, alcohol consumption, hypertension, and diabetes were independently associated with MAU. Microalbuminuria may be a useful indicator for risk of CV disease in general populations.
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[The optimal cut-off value of waist-to-height ratio for detecting severe central obesity and low body weightin adult Chinese population].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 11-29-2013
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To explore the optimal cut-off values of waist-to-height ratio (WHtR) for detecting the severe central obesity and low body weight in adult Chinese population.
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Whole-Genome Sequencing of Lactobacillus shenzhenensis Strain LY-73T.
Genome Announc
PUBLISHED: 11-23-2013
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Lactobacillus shenzhenensis strain LY-73(T) is a novel species which was first isolated from fermented goods. Here, we report the draft genome sequence of Lactobacillus shenzhenensis LY-73(T).
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Formaldehyde concentration and its influencing factors in residential homes after decoration at Hangzhou, China.
J Environ Sci (China)
PUBLISHED: 11-14-2013
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Air pollution surveys of formaldehyde (HCHO) were conducted in 2324 rooms decorated within one year in 2007-2009 in Hangzhou, China. The mean HCHO concentration (CHCHO) was 0.107 +/- 0.095 mg/m3, and 38.9% of samples exceeded the Chinese National Standard GB 50325-2010. Over the past 3 years, the C(HCHO) decreased with time (p < 0.05). Relationships of potential factors to indoor C(HCHO) were also evaluated. C(HCHO) was related to temperature (T), relative humidity (RH), time duration of the windows and doors being closed before sampling (DC), time duration from the end of decoration to sampling (DR) and source characteristics (d). A model to relate indoor C(HCHO) to these five factors (T, RH, DC, DR, d) was established based on 298 samples (R2 = 0.87). Various factors contributed to C(HCHO) in the following order: T, 43.7%; d, 31.0%; DC, 10.2%; DR, 8.0%; RH, 7.0%; specifically, meteorological conditions (i.e., RH plus T) accounted for 50.7%. The coefficient of T and RH, R(TH), was proposed to describe their combined influence on HCHO emission, which also had a linear relationship (R2 = 0.9387) with HCHO release in a simulation chamber test. In addition, experiments confirm that it is a synergistic action as T and RH accelerate the release of HCHO, and that is a significant factor influencing indoor HCHO pollution. These achievements could lead to reference values of measures for the efficient reduction of indoor HCHO pollution.
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Evolved Quorum Sensing Regulator, LsrR, for Altered Switching Functions.
ACS Synth Biol
PUBLISHED: 10-10-2013
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In order to carry out innovative complex, multistep synthetic biology functions, members of a cell population often must communicate with one another to coordinate processes in a programmed manner. It therefore follows that native microbial communication systems are a conspicuous target for developing engineered populations and networks. Quorum sensing (QS) is a highly conserved mechanism of bacterial cell-cell communication and QS-based synthetic signal transduction pathways represent a new generation of biotechnology toolbox members. Specifically, the E. coli QS master regulator, LsrR, is uniquely positioned to actuate gene expression in response to a QS signal. In order to expand the use of LsrR in synthetic biology, two novel LsrR switches were generated through directed evolution: an "enhanced" repression and derepression eLsrR and a reversed repression/derepression function "activator" aLsrR. Protein modeling and docking studies are presented to gain insight into the QS signal binding to these two evolved proteins and their newly acquired functionality. We demonstrated the use of the aLsrR switch using a coculture system in which a QS signal, produced by one bacterial strain, is used to inhibit gene expression via aLsrR in a different strain. These first ever AI-2 controlled synthetic switches allow gene expression from the lsr promoter to be tuned simultaneously in two distinct cell populations. This work expands the tools available to create engineered microbial populations capable of carrying out complex functions necessary for the development of advanced synthetic products.
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Crystal structures of the LsrR proteins complexed with phospho-AI-2 and two signal-interrupting analogues reveal distinct mechanisms for ligand recognition.
J. Am. Chem. Soc.
PUBLISHED: 10-01-2013
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Quorum sensing (QS) is a cell-to-cell communication system responsible for a variety of bacterial phenotypes including virulence and biofilm formation. QS is mediated by small molecules, autoinducers (AIs), including AI-2 that is secreted by both Gram-positive and -negative microbes. LsrR is a key transcriptional regulator that governs the varied downstream processes by perceiving AI-2 signal, but its activation via autoinducer-binding remains poorly understood. Here, we provide detailed regulatory mechanism of LsrR from the crystal structures in complexes with the native signal (phospho-AI-2, D5P) and two quorum quenching antagonists (ribose-5-phosphate, R5P; phospho-isobutyl-AI-2, D8P). Interestingly, the bound D5P and D8P molecules are not the diketone forms but rather hydrated, and the hydrated moiety forms important H-bonds with the carboxylate of D243. The D5P-binding flipped out F124 of the binding pocket, and resulted in the disruption of the dimeric interface-1 by unfolding the ?7 segment. However, the same movement of F124 by the D8P-binding did not cause the unfolding of the ?7 segment. Although the LsrR-binding affinity of R5P (Kd, ?1 mM) is much lower than that of D5P and D8P (?2.0 and ?0.5 ?M), the ?-anomeric R5P molecule fits into the binding pocket without any structural perturbation, and thus stabilizes the LsrR tetramer. The binding of D5P, not D8P and R5P, disrupted the tetrameric structure and thus is able to activate LsrR. The detailed structural and mechanistic insights from this study could be useful for facilitating design of new antivirulence and antibiofilm agents based on LsrR.
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Universal scheme to generate metal-insulator transition in disordered systems.
J Phys Condens Matter
PUBLISHED: 09-18-2013
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We propose a scheme to generate metal-insulator transition in the random binary layer (RBL) model, which is constructed by randomly assigning two types of layers along the longitudinal direction. Based on a tight-binding Hamiltonian, the localization length is calculated for a variety of RBLs with different cross section geometries by using the transfer-matrix method. Both analytical and numerical results show that a band of extended states could appear in the quasi-one-dimensional RBLs and the systems behave as metals by properly tuning the model parameters, due to the existence of a completely ordered subband, leading to a metal-insulator transition in parameter space. Furthermore, the extended states are irrespective of the diagonal and off-diagonal disorder strengths. Our results can be generalized to two- and three-dimensional disordered systems with arbitrary layer structures, and may be realized in Bose-Einstein condensates.
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[Development of a rapid screening method for discovering neuroprotective components from traditional Chinese medicine].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 08-17-2013
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This study developed a method for rapid screening neuroprotective compounds with FDA (fluorescein diacetate) labeled SH-SYSY cells, which was injuried by Glu (L-glutamic acid). The cell viability was determined by fluorescence automatic mi-croscopy screening system. Then, neuroprotective components from Gegen Qinlian decoction were screened by the proposed method. The results demonstrated that 4 chemical components, C15, D06, D07 and E05 from Gegen Qinlian decoction, showed significantly neuroprotective effects. Furthermore, 8 compounds (i. e. daidzin, 3-methoxydaidzin, liquiritin apioside, 6-C-L-alpha-arabinopyranosyl-8-C-beta-D-glucopyranosyl chrysin, isoliquiritin apioside, baicalin, oroxylin-A-7-O-fP-D-glucuronide and wogonoside) were identified from these active components by LC-Q/TOF-MS technology (liquid chromatography quadrupole time of flight tandem mass spectrometry). These 8 compounds may be the potential neuroprotective substances in Gegen Qinlian decoction.
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[An approach to screen nephrotoxic components in traditional Chinese medicine based on fluorescent probe and HK-2 cells and its application].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 08-17-2013
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Using fluorescein diacetate labeled HK-2 cells, a fast method for screening nephrotoxic components in traditional Chinese medicines (TCMs) was proposed in this study. The methodology validation showed that the linearity, stability and accuracy of the proposed method were suitable for screening nephrotoxic components in vitro . This method was further applied on screen 352 components from 32 Chinese Pharmacopoeia-indexed toxic TCMs. The results indicated that 31 components from 14 toxic TCMs, including Badou, had significant toxicity on HK-2 cells, which suggested these components may cause nephrotoxicity. The components from the other 18 toxic TCMs had no significant toxicity on HK-2 cells.
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Association of depression with adverse cardiovascular events after percutaneous coronary intervention.
Coron. Artery Dis.
PUBLISHED: 08-14-2013
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The aim of this study was to investigate the impact of depression on the clinical outcomes of patients with coronary artery disease undergoing percutaneous coronary intervention (PCI).
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Celastrol prevents cadmium-induced neuronal cell death via targeting JNK and PTEN-Akt/mTOR network.
J. Neurochem.
PUBLISHED: 08-10-2013
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Cadmium (Cd), a toxic environmental contaminant, induces neurodegenerative diseases. Celastrol, a plant-derived triterpene, has shown neuroprotective effects in various disease models. However, little is known regarding the effect of celastrol on Cd-induced neurotoxicity. Here we show that celastrol protected against Cd-induced apoptotic cell death in neuronal cells. This is supported by the findings that celastrol strikingly attenuated Cd-induced viability reduction, morphological change, nuclear fragmentation and condensation, as well as activation of caspase-3 in neuronal cells. Concurrently, celastrol remarkably blocked Cd-induced phosphorylation of c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinases 1/2 (Erk1/2) and p38, in neuronal cells. Inhibition of JNK by SP600125 or overexpression of dominant negative c-Jun potentiated celastrol protection against Cd-induced cell death. Furthermore, pre-treatment with celastrol prevented Cd downregulation of phosphatase and tensin homologue deleted on chromosome 10 (PTEN) and activation of Akt/mammalian target of rapamycin (mTOR) signaling in neuronal cells. Overexpression of wild-type PTEN enhanced celastrol inhibition of Cd-activated Akt/mTOR signaling and cell death in neuronal cells. The findings indicate that celastrol prevents Cd-induced neuronal cell death via targeting JNK and PTEN-Akt/mTOR network. Our results strongly suggest that celastrol may be exploited for the prevention of Cd-induced neurodegenerative disorders. This article is protected by copyright. All rights reserved.
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Expression of cellular fibronectin mRNA in adult periodontitis and peri-implantitis: a real-time polymerase chain reaction study.
Int J Oral Sci
PUBLISHED: 06-26-2013
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Cellular fibronectin (cFn) is a type of bioactive non-collagen glycoprotein regarded as the main substance used to maintain periodontal attachment. The content of cFn in some specific sites can reflect the progress of periodontitis or peri-implantitis. This study aims to evaluate the expression of cFn messenger RNA (mRNA) in tissues of adult periodontitis and peri-implantitis by real-time fluorescent quantitative polymerase chain reaction (PCR) and to determine its clinical significance. A total of 30 patients were divided into three groups of 10: healthy, adult periodontitis and peri-implantitis. Periodontal tissue biopsies (1 mm×1 mm×1 mm) from each patient were frozen in liquid nitrogen. Total RNA was extracted from these tissues, and the content, purity and integrity were detected. Specific primers were designed according to the sequence, and the mRNA expression levels of cellular fibronectin were detected by real-time PCR. The purity and integrity of the extracted total RNA were both high, and the specificity of amplified genes was very high with no other pollution. The mRNA expression of cFn in the adult periodontitis group (1.526±0.441) was lower than that in the healthy group (3.253±0.736). However, the mRNA expression of cFn in the peri-implantitis group (3.965±0.537) was significantly higher than that in the healthy group. The difference revealed that although both processes were destructive inflammatory reactions in the periodontium, the pathomechanisms were different and the variation started from the transcription level of the cFn gene.
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Chemical inhibition of prometastatic lysyl-tRNA synthetase-laminin receptor interaction.
Nat. Chem. Biol.
PUBLISHED: 06-18-2013
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Lysyl-tRNA synthetase (KRS), a protein synthesis enzyme in the cytosol, relocates to the plasma membrane after a laminin signal and stabilizes a 67-kDa laminin receptor (67LR) that is implicated in cancer metastasis; however, its potential as an antimetastatic therapeutic target has not been explored. We found that the small compound BC-K-YH16899, which binds KRS, impinged on the interaction of KRS with 67LR and suppressed metastasis in three different mouse models. The compound inhibited the KRS-67LR interaction in two ways. First, it directly blocked the association between KRS and 67LR. Second, it suppressed the dynamic movement of the N-terminal extension of KRS and reduced membrane localization of KRS. However, it did not affect the catalytic activity of KRS. Our results suggest that specific modulation of a cancer-related KRS-67LR interaction may offer a way to control metastasis while avoiding the toxicities associated with inhibition of the normal functions of KRS.
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N-O tethered carbenoid cyclopropanation facilitates the synthesis of a functionalized cyclopropyl-fused pyrrolidine.
J. Org. Chem.
PUBLISHED: 06-05-2013
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We report a facile approach to a cyclopropyl-fused pyrrolidine, which contains four stereogenic centers, by employing the N-O tethered carbenoid methodology. The synthesis was facilitated by the development of a direct Mitsunobu reaction of alcohols with N-alkyl-N-hydroxyl amides to give diazo precursors, which upon intramolecular cyclopropanation yielded a library of N-O containing cyclopropyl-fused bicyclic intermediates. Elaboration of the N-O moiety of one member of this library resulted in the formation of the desired pyrrolidine ring demonstrating the potential of this methodology for making cyclopropyl-fused heterocycles.
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Small molecule inhibitors of AI-2 signaling in bacteria: state-of-the-art and future perspectives for anti-quorum sensing agents.
Int J Mol Sci
PUBLISHED: 06-03-2013
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Bacteria respond to different small molecules that are produced by other neighboring bacteria. These molecules, called autoinducers, are classified as intraspecies (i.e., molecules produced and perceived by the same bacterial species) or interspecies (molecules that are produced and sensed between different bacterial species). AI-2 has been proposed as an interspecies autoinducer and has been shown to regulate different bacterial physiology as well as affect virulence factor production and biofilm formation in some bacteria, including bacteria of clinical relevance. Several groups have embarked on the development of small molecules that could be used to perturb AI-2 signaling in bacteria, with the ultimate goal that these molecules could be used to inhibit bacterial virulence and biofilm formation. Additionally, these molecules have the potential to be used in synthetic biology applications whereby these small molecules are used as inputs to switch on and off AI-2 receptors. In this review, we highlight the state-of-the-art in the development of small molecules that perturb AI-2 signaling in bacteria and offer our perspective on the future development and applications of these classes of molecules.
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Exome sequencing identifies a significant variant in methionyl-tRNA synthetase (MARS) in a family with late-onset CMT2.
J. Neurol. Neurosurg. Psychiatr.
PUBLISHED: 06-01-2013
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Charcot-Marie-Tooth (CMT) disease is a genetically heterogeneous condition with >50 genes now being identified. Thanks to new technological developments, namely, exome sequencing, the ability to identify additional rare genes in CMT has been drastically improved. Here we present data suggesting that MARS is a very rare novel cause of late-onset CMT2. This is supported by strong functional and evolutionary evidence, yet the absence of additional unrelated cases warrant future studies to substantiate this conclusion.
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Comparative analysis of proteomic profiles between endometrial caruncular and intercaruncular areas in ewes during the peri-implantation period.
J Anim Sci Biotechnol
PUBLISHED: 05-16-2013
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The endometrium of sheep consists of plenty of raised aglandular areas called caruncular (C), and intensely glandular intercaruncular areas (IC). In order to better understand the endometrium involved mechanisms of implantation, we used LC-MS/MS technique to profile the proteome of ovine endometrial C areas and IC areas separately during the peri-implantation period, and then compared the proteomic profiles between these two areas. We successfully detected 1740 and 1813 proteins in C areas and IC areas respectively. By comparing the proteome of these two areas, we found 170 differentially expressed proteins (DEPs) (P < 0.05), functional bioinformatics analysis showed these DEPs were mainly involved in growth and remodeling of endometrial tissue, cell adhesion and protein transport, and so on. Our study, for the first time, provided a proteomic reference for elucidating the differences between C and IC areas, as an integrated function unit respectively, during the peri-implantation period. The results could help us to better understand the implantation in the ewes. In addition, we established a relatively detailed protein database of ovine endometrium, which provide a unique reference for further studies.
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[Effects of experimentally created unilateral anterior crossbite prosthesis on the expression of parathyroid hormone-related peptide and parathyroid hormone receptor-1 in mandibular condylar cartilage of rat].
Hua Xi Kou Qiang Yi Xue Za Zhi
PUBLISHED: 05-14-2013
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To study the effects of experimentally created unilateral anterior crossbite prosthesis on the expression of parathyroid hormone-related peptide (PTHrP) and parathyroid hormone receptor-1 (PTH1R) in mandibular condylar cartilage of SD rat.
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[Preliminary study of HCT-CI score system for prognosis prediction in elderly patients with acute myeloid leukemia after chemotherapy].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 04-20-2013
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To investigate the value of the HCT-CI score in chemotherapy risk assessment and prognosis of elderly patients with acute myeloid leukemia (AML).
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Inactivation of specific ? cell transcription factors in type 2 diabetes.
J. Clin. Invest.
PUBLISHED: 03-29-2013
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Type 2 diabetes (T2DM) commonly arises from islet ? cell failure and insulin resistance. Here, we examined the sensitivity of key islet-enriched transcription factors to oxidative stress, a condition associated with ? cell dysfunction in both type 1 diabetes (T1DM) and T2DM. Hydrogen peroxide treatment of ? cell lines induced cytoplasmic translocation of MAFA and NKX6.1. In parallel, the ability of nuclear PDX1 to bind endogenous target gene promoters was also dramatically reduced, whereas the activity of other key ? cell transcriptional regulators was unaffected. MAFA levels were reduced, followed by a reduction in NKX6.1 upon development of hyperglycemia in db/db mice, a T2DM model. Transgenic expression of the glutathione peroxidase-1 antioxidant enzyme (GPX1) in db/db islet ? cells restored nuclear MAFA, nuclear NKX6.1, and ? cell function in vivo. Notably, the selective decrease in MAFA, NKX6.1, and PDX1 expression was found in human T2DM islets. MAFB, a MAFA-related transcription factor expressed in human ? cells, was also severely compromised. We propose that MAFA, MAFB, NKX6.1, and PDX1 activity provides a gauge of islet ? cell function, with loss of MAFA (and/or MAFB) representing an early indicator of ? cell inactivity and the subsequent deficit of more impactful NKX6.1 (and/or PDX1) resulting in overt dysfunction associated with T2DM.
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Hepatitis B virus core protein enhances human telomerase reverse transcriptase expression and hepatocellular carcinoma cell proliferation in a c-Ets2-dependent manner.
Int. J. Biochem. Cell Biol.
PUBLISHED: 03-10-2013
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Hepatitis B virus core protein can regulate viral replication and host gene expression. However, it is unclear whether and how hepatitis B virus core protein regulates hepatocellular carcinoma cell proliferation. Induction of hepatitis B virus core protein over-expression significantly enhanced the proliferation of hepatocellular carcinoma cells, while knockdown of hepatitis B virus core protein expression inhibited the proliferation of hepatocellular carcinoma cells. Altered hepatitis B virus core protein expression significantly changed the growth of implanted hepatocellular carcinoma in vivo. Microarray analysis indicated that hepatitis B virus core protein up-regulated human telomerase reverse transcriptase expression, which was further validated by over-expression and knockdown assays in vitro. Furthermore, knockdown of human telomerase reverse transcriptase expression mitigated the hepatitis B virus core protein-enhanced hepatocellular carcinoma cell proliferation and clone formation in vitro. Luciferase assays indicated that hepatitis B virus core protein enhanced the promoter activity of human telomerase reverse transcriptase, which was dependent on the binding of c-Ets2 to the promoter region between -192 and -187. In addition, hepatitis B virus core protein enhanced human telomerase reverse transcriptase transcription in HepG2 cells, but not in the c-Ets2-silencing HepG2 cells. Moreover, hepatitis B virus core protein promoted c-Ets2 nuclear translocation. Finally, significantly higher levels of human telomerase reverse transcriptase expression and nuclear c-Ets2 accumulation were detected in hepatitis B virus core protein-positive hepatocellular carcinoma samples. Our findings demonstrate that hepatitis B virus core protein promotes hepatocellular carcinoma cell proliferation by up-regulating the c-Ets2-dependent expression of human telomerase reverse transcriptase.
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Distal-less regulates eyespot patterns and melanization in Bicyclus butterflies.
J. Exp. Zool. B Mol. Dev. Evol.
PUBLISHED: 03-09-2013
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Butterfly eyespots represent novel complex traits that display substantial diversity in number and size within and across species. Correlative gene expression studies have implicated a large suite of transcription factors, including Distal-less (Dll), Engrailed (En), and Spalt (Sal), in eyespot development in butterflies, but direct evidence testing the function of any of these proteins is still missing. Here we show that the characteristic two-eyespot pattern of wildtype Bicyclus anynana forewings is correlated with dynamic progression of Dll, En, and Sal expression in larval wings from four spots to two spots, whereas no such decline in gene expression ensues in a four-eyespot mutant. We then conduct transgenic experiments testing whether over-expression of any of these genes in a wild-type genetic background is sufficient to induce eyespot differentiation in these pre-patterned wing compartments. We also produce a Dll-RNAi transgenic line to test how Dll down-regulation affects eyespot development. Finally we test how ectopic expression of these genes during the pupal stages of development alters adults color patters. We show that over-expressing Dll in larvae is sufficient to induce the differentiation of additional eyespots and increase the size of eyespots, whereas down-regulating Dll leads to a decrease in eyespot size. Furthermore, ectopic expression of Dll in the early pupal wing led to the appearance of ectopic patches of black scales. We conclude that Dll is a positive regulator of focal differentiation and eyespot signaling and that this gene is also a possible selector gene for scale melanization in butterflies.
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hsBAFF promotes proliferation and survival in cultured B lymphocytes via calcium signaling activation of mTOR pathway.
Cytokine
PUBLISHED: 02-27-2013
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B-cell activating factor of the TNF family (BAFF, also called BLyS, TALL-1, THANK, or zTNF4) has revealed its critical function in B lymphocyte proliferation and survival, as well as the pathogenesis of autoimmune disease. However, the molecular mechanisms of excess BAFF-extended aggressive B lymphocytes have not been completely defined. Here we show that excessive hsBAFF-elevated [Ca(2+)]i activated mammalian target of rapamycin (mTOR) signaling pathway, leading to proliferation and survival in B lymphocytes. This is supported by the findings that intracellular Ca(2+) chelator (BAPTA/AM) or mTOR inhibitor (rapamycin) abolished the events. Sequentially, we observed that preventing [Ca(2+)]i elevation using EGTA or 2-APB dramatically inhibited hsBAFF activation of mTOR signaling, as well as cell growth and survival, suggesting that hsBAFF-induced extracellular Ca(2+) influx and ER Ca(2+) release elevates [Ca(2+)]i contributing to B lymphocyte proliferation and survival via activation of mTOR signaling. Further, we noticed that pretreatment with BAPTA/AM, EGTA or 2-APB blocked hsBAFF-increased phosphorylation of calcium/calmodulin-dependent protein kinase II (CaMKII), and inhibiting CaMKII with KN93 attenuated hsBAFF-activated mTOR signaling, as well as cell growth and survival, revealing that the effects of hsBAFF-elevated [Ca(2+)]i on mTOR signaling as well as proliferation and survival in B lymphocytes is through stimulating phosphorylation of CaMKII. The results indicate that hsBAFF activates mTOR pathway triggering B lymphocyte proliferation and survival by calcium signaling. Our findings suggest that manipulation of intracellular Ca(2+) level or CaMKII and mTOR activity may be exploited for the prevention of excessive BAFF-induced aggressive B lymphocyte disorders and autoimmune diseases.
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Essential nontranslational functions of tRNA synthetases.
Nat. Chem. Biol.
PUBLISHED: 02-19-2013
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Nontranslational functions of vertebrate aminoacyl tRNA synthetases (aaRSs), which catalyze the production of aminoacyl-tRNAs for protein synthesis, have recently been discovered. Although these new functions were thought to be moonlighting activities, many are as critical for cellular homeostasis as their activity in translation. New roles have been associated with their cytoplasmic forms as well as with nuclear and secreted extracellular forms that affect pathways for cardiovascular development and the immune response and mTOR, IFN-? and p53 signaling. The associations of aaRSs with autoimmune disorders, cancers and neurological disorders further highlight nontranslational functions of these proteins. New architecture elaborations of the aaRSs accompany their functional expansion in higher organisms and have been associated with the nontranslational functions for several aaRSs. Although a general understanding of how these functions developed is limited, the expropriation of aaRSs for essential nontranslational functions may have been initiated by co-opting the amino acid-binding site for another purpose.
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Dysregulated expression of T cell immunoglobulin and mucin domain 3 is associated with the disease severity and the outcome of patients with spontaneous intracerebral hemorrhage.
Clin. Biochem.
PUBLISHED: 02-01-2013
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We aimed to investigate the expression of T cell immunoglobulin and mucin domain 3 (Tim-3) on peripheral blood cells in spontaneous intracerebral hemorrhage (ICH) patients and to analyze its clinical significance.
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Shared and distinct functions of two Gti1/Pac2 family proteins in growth, morphogenesis and pathogenicity of Magnaporthe oryzae.
Environ. Microbiol.
PUBLISHED: 01-29-2013
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Gti1/Pac2 are conserved family proteins that regulate morphogenic transition in yeasts such as Schizosaccharomyces pombe and Candida albicans, and they also control toxin production and pathogenicity in filamentous fungus Fusarium graminearum. To test the functions of Gti1/Pac2 paralogues MoGti1 and MoPac2 in the rice blast fungus Magnaporthe oryzae, we generated respective ?Mogti1 and ?Mopac2 mutant strains. We found that MoGti1 and MoPac2 exhibit shared and distinct roles in hyphal growth, conidiation, sexual reproduction, stress responses, surface hydrophobility, invasive hyphal growth and pathogenicity. Consistent with the putative conserved function of MoGti1, we showed that MoGti1-GFP is localized to the nucleus, whereas MoPac2-GFP is mainly found in the cytoplasm. In addition, we provided evidence that the nuclear localization of MoGti1 could be subject to regulation by MoPmk1 mitogen-activated protein kinase. Moreover, we found that the reduced pathogenicity in the ?Mopac2 mutant corresponds with an increased expression of plant defence genes, including PR1a, AOS2, LOX1, PAD4, and CHT1. Taken together, our studies provide a comprehensive analysis of two similar but distinct Gti1/Pac2 family proteins in M.?oryzae, which underlines the important yet conserved functions of these family proteins in plant pathogenic fungi.
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Facile optimization for chromatographic separation of liquiritin and liquiritigenin.
J Chromatogr A
PUBLISHED: 01-17-2013
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A reversed phase chromatographic system, composed of a stationary phase of C18 silica gel (ODS, 20?m) and a mobile phase of ethanol/water, was used to separate liquiritin and liquiritigenin in the raw material of flavonoids. The linear adsorption isotherm and the equilibrium-dispersive model were adopted to approximatively describe the chromatographic separation behaviors of liquiritin and liquiritigenin in the raw material under different column temperatures, ethanol contents and flow rates of the mobile phase, sample concentrations and feeding times. Combined with orthogonal design, the ED model was used to optimize the chromatographic separating conditions, the corresponding experimental result with a good agreement was obtained and the overload separation was realized.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.