2,045 research outputs found

    Correlation between Myocardial Velocity Measured using Tissue Doppler Imaging in the Left Ventricular Lead-Implanted Segment and Response to Cardiac Resynchronization Therapy

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    OBJECTIVES: This study investigated whether tissue Doppler imaging parameters, especially the peak systolic velocity of the left ventricular lead-implanted segment (Ss), affect cardiac resynchronization therapy response. METHODS: In this case-control study, 110 enrolled patients were divided into cases (responder group, n=65) and controls (nonresponder group, n=45) based on whether their left ventricular end-systolic volume was reduced by X15% at 6 months after surgery. Preoperative clinical and echocardiographic data were collected. Multivariate logistic regression models were used to analyze the factors affecting the response to cardiac resynchronization therapy, and receiver operating characteristic curves were plotted to evaluate their diagnostic values. RESULTS: The proportion of patients with left bundle branch block in the case group was higher than that in the control group. The control group showed a higher left atrial volume index, E/A ratio and E/Em ratio but lower Ss than that of the case group. A multivariate regression analysis showed that left bundle branch block, Ss, and an E/Em ratio414 were independent risk factors affecting the response to cardiac resynchronization therapy. Ss=4.1 cm/s was the best diagnostic threshold according to the receiver operating characteristic curve. CONCLUSIONS: Ss is an important factor affecting the response to cardiac resynchronization therapy. Patients with heart failure associated with Sso4.1 cm/s have a higher risk of nonresponse

    Robust 3.7 V-Na2/3_{2/3}[Cu1/3_{1/3}Mn2/3_{2/3}]O2_2 Cathode for Na-ion Batteries

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    Na-ion batteries (NIBs), which are recognized as a next-generation alternative technology for energy storage, still suffer from commercialization constraints due to the lack of low-cost, high-performance cathode materials. Since our first discovery of Cu3+^{3+}/Cu2+^{2+} electrochemistry in 2014, numerous Cu-substituted/doped materials have been designed for NIBs. However for almost ten years, the potential of Cu3+^{3+}/Cu2+^{2+} electrochemistry has been grossly underappreciated and normally regarded as a semielectrochemically active redox. Here, we re-synthesized P2-Na2/3_{2/3}[Cu1/3_{1/3}Mn2/3_{2/3}]O2_2 and reinterpreted it as a high-voltage, cost-efficient, air-stable, long-life, and high-rate cathode material for NIBs, which demonstrates a high operating voltage of 3.7 V and a completely active Cu3+^{3+}/Cu2+^{2+} redox reaction. The 2.3 Ah cylindrical cells exhibit excellent cycling (93.1% capacity after 2000 cycles), high rate (97.2% capacity at 10C rate), good low-temperature performance (86.6% capacity at -30∘^\circC), and high safety, based on which, a 56 V-11.5 Ah battery pack for E-bikes is successfully constructed, exhibiting stable cycling (96.5% capacity at the 800th cycle) and a long driving distance (36 km, tester weight 65 kg). This work offers a commercially feasible cathode material for low-cost, high-voltage NIBs, paving the way for advanced NIBs in power and stationary energy storage applications.Comment: 15 pages, 3 figures, 1 tabl

    Suppression of lung cancer in murine model: treated by combination of recombinant human endostsatin adenovirus with low-dose cisplatin

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    <p>Abstract</p> <p>Background</p> <p>The sustained growth of tumors necessitates neovascularization. As one of the potent endogenous vascular inhibitors, endostatin has been widely used in antiangiogenesis therapy for tumor. Cisplatin is normally administered in chemotherapy for lung cancer but accompanied with serious side effects. In the current study, we investigated a novel chemo-antiangiogenesis therapeutic strategy to both improve toxic effects on lung cancer cells and reduce damages to normal cells in the anti-tumor therapy.</p> <p>Methods</p> <p>In vitro, we transduced LLC cells with Ad-hEndo and collected supernatants. Western blotting analysis of the supernatants revealed expression of endostatin. In vivo, to fully investigate the suppression effect on murine lung cancer of the combination therapy, we injected recombinant human endostatin adenovirus intratumorally plus a low dose of cisplatin intraperitoneally routinely. The tumor volume and survival time were observed. Angiogenesis was apparently inhibited within the tumor tissues and on the alginate beads. Assessment of apoptotic cells by the TUNEL assay was conducted in the tumor tissues.</p> <p>Results</p> <p>The combination treatment significantly suppressed the tumor growth and prolonged survival time of the murine LLC tumor model. This anti-tumor activity was associated with decreased microvessel density and increased apoptotic index of tumor cells.</p> <p>Conclusion</p> <p>According to the results in this study, recombinant human endostatin adenovirus in combination with a low dose of cisplatin demonstrated apparent synergistic anti-tumor activity without marked toxicity. Thus, these observations may provide a rational alternative for lung cancer treatment.</p

    Ambient air pollution in relation to diabetes and glucose-homoeostasis markers in China: a cross-sectional study with findings from the 33 Communities Chinese Health Study

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    Background: Health effects of air pollution on diabetes have been scarcely studied in developing countries. We aimed to explore the associations of long-term exposure to ambient particulate matter (PM) and gaseous pollutants with diabetes prevalence and glucose-homoeostasis markers in China. Methods: Between April 1 and Dec 31, 2009, we recruited a total of 15 477 participants aged 18–74 years using a random number generator and a four-staged, stratified and cluster sampling strategy from a large cross-sectional study (the 33 Communities Chinese Health Study) from three cities in Liaoning province, northeastern China. Fasting and 2 h insulin and glucose concentrations and the homoeostasis model assessment of insulin resistance index and β-cell function were used as glucose-homoeostasis markers. Diabetes was defined according to the American Diabetes Association's recommendations. We calculated exposure to air pollutants using data from monitoring stations (PM with an aerodynamic diameter of 10 μm or less [PM10], sulphur dioxide, nitrogen dioxide, and ozone) and a spatial statistical model (PM with an aerodynamic diameter of 1 μm or less [PM1] and 2·5 μm or less [PM2·5]). We used two-level logistic regression and linear regression analyses to assess associations between exposure and outcomes, controlling for confounders. Findings: All the studied pollutants were significantly associated with increased diabetes prevalence (eg, the adjusted odds ratios associated with an increase in IQR for PM1, PM2·5, and PM10 were 1·13, 95% CI 1·04–1·22; 1·14, 1·03–1·25; and 1·20, 1·12–1·28, respectively). These air pollutants were also associated with higher concentrations of fasting glucose (0·04–0·09 mmol/L), 2 h glucose (0·10–0·19 mmol/L), and 2 h insulin (0·70–2·74 μU/L). No association was observed for the remaining biomarkers. Stratified analyses indicated greater effects on the individuals who were younger (<50 years) or overweight or obese. Interpretation: Long-term exposure to air pollution was associated with increased risk of diabetes in a Chinese population, particularly in individuals who were younger or overweight or obese. Funding: The National Key Research and Development Program of China, the National Natural Science Foundation of China, the Fundamental Research Funds for the Central Universities, the Guangdong Province Natural Science Foundation, the Career Development Fellowship of Australian National Health and Medical Research Council, and the Early Career Fellowship of Australian National Health and Medical Research Council

    Local partitioning of the overturning circulation in the tropics and the connection to the Hadley and Walker circulations

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    Conceptually, it is useful to partition the three-dimensional tropical circulation into meridional and zonal components, namely, the Hadley and Walker circulations. The averaging involved in their definitions can introduce ambiguities. These problems can be circumvented by first partitioning the total vertical mass flux into components associated with overturning in the meridional and zonal directions, respectively, called here the local Hadley and local Walker circulations. Defining the local Hadley and local Walker circulations this way ensures the pair of two-dimensional overturning circulations can be added to give the original three-dimensional circulation, even when the averages are taken over limited domains. The method is applied to the vertical motion from the ERA-Interim reanalysis for the period 1979 to 2009. One important result is that the local Hadley circulation responds much more strongly to ENSO than the local Walker circulation, even though the local Walker circulation in the central Pacific weakens during El Niño years and strengthens and widens during La Niña years

    Enhanced heating rate of black carbon above planetary boundary layer over megacities in summertime

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    The fast development of a secondary aerosol layer was observed over megacities in eastern Asia during summertime. Within three hours, from midday to early afternoon, the contribution of secondary aerosols above the planetary boundary layer (PBL) increased by a factor of 3-5, and the coatings on the black carbon (BC) also increased and enhanced its absorption efficiency by 50%. This tended to result from the intensive actinic flux received above the PBL which promoted the photochemical reactions. The absorption of BC could be further amplified by the strong reflection of solar radiation over the cloud top across the PBL. This enhanced heating effect of BC introduced by combined processes (intensive solar radiation, secondary formation and cloud reflection) may considerably increase the temperature inversion above the PBL. This mechanism should be considered when evaluating the radiative impact of BC, especially for the polluted regions receiving strong solar radiation
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