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BACKGROUND: The aim of this study was to assess the role of lipolysis of epicardial adipose tissue (EAT) in cardiac function after myocardial infarction (MI). METHODS: We used a rat model of MI with or without EAT removal to study the effects of EAT lipolysis on cardiovascular function. Echocardiography and cardiac catheterization were used to determine cardiac function, and infarct size and histopathology specimens were analyzed in postmortem sections. Inflammatory responses were evaluated via flow cytometry and Elisa analyses. RESULTS: We found that the lipolysis of EAT increased significantly after MI. Removal of the EAT after MI (MI-EAT) improved cardiac function by nearly 10% and decreased the infarct area by 6% when compared with rats retaining EAT after MI (MI+EAT). Furthermore, the removal of EAT reduced the number of CD45-positive leukocytes (50 vs. 34.8%) and increased the ratio of macrophage/leukocytes (56 vs. 75%) in the infarcted heart. Compared with the MI+EAT group, the concentration of tumor necrosis factor-alpha and interleukin 1beta were reduced in the MI-EAT group. CONCLUSION: Lipolysis of EAT increased significantly after MI. Removal of EAT improved cardiac function, in part, by weakening the inflammatory response.
Assuntos
Tecido Adiposo , Lipólise , Infarto do Miocárdio , Animais , Ecocardiografia , Pericárdio , Ratos , Ratos Sprague-DawleyRESUMO
A method to achieve stable radiation pressure acceleration (RPA) of heavy ions from laser-irradiated ultrathin foils is proposed, where a high-Z material coating in front is used. The coated high-Z material, acting as a moving electron repository, continuously replenishes the accelerating heavy ion foil with comoving electrons in the light-sail acceleration stage due to its successive ionization under laser fields with Gaussian temporal profile. As a result, the detrimental effects such as foil deformation and electron loss induced by the Rayleigh-Taylor-like and other instabilities in RPA are significantly offset and suppressed so that stable acceleration of heavy ions are maintained. Particle-in-cell simulations show that a monoenergetic Al^{13+} beam with peak energy 3.8 GeV and particle number 10^{10} (charge >20 nC) can be obtained at intensity 10^{22} W/cm^{2}.
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Although a number of studies have been conducted on the association between the peptidylarginine deiminase (PADI4) -94G/A polymorphism and rheumatoid arthritis (RA) in the Chinese population, the association remains elusive and controversial. To clarify the impact of the PADI4 -94G/A polymorphism on the risk of RA, a meta-analysis was performed in the Chinese population. Related studies were identified from databases such as, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform, Chinese National Knowledge Infrastructure (CNKI), and Chinese Biology Medicine (CBM) up to May 21, 2015. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of associations. A total of 10 studies with 2783 RA cases and 2887 controls were included in this meta-analysis. Overall, a significantly elevated risk of RA was associated with all variants of PADI4 -94G/A (A vs G: OR = 1.24, 95%CI = 1.15-1.34; AA + GA vs GG: OR = 1.45, 95%CI = 1.29-1.62; AA vs GG: OR = 1.49, 95%CI = 1.28-1.73; AA vs GG + GA: OR = 1.19, 95%CI = 1.04-1.35). Subgroup analyses stratified by geographic areas and source of controls revealed significant results in the population-based studies in North and South China. In conclusion, this meta-analysis showed that the PADI4 -94G/A variants may influence RA risk in the Chinese population. However, further studies with gene-gene and gene-environment interactions are required for definite conclusions.
Assuntos
Artrite Reumatoide/genética , Hidrolases/genética , Polimorfismo de Nucleotídeo Único/genética , Povo Asiático , China , Predisposição Genética para Doença/genética , Humanos , Proteína-Arginina Desiminase do Tipo 4 , Desiminases de Arginina em ProteínasRESUMO
The Cadmium (Cd)-polluted soils are is an increasing concern worldwide. Phytoextraction of Cd pollutants by high biomass plants, such as sweet sorghum, is considered an environmentally-friendly, cost-effective and sustainable strategy for remediating this problem. Nitrogen (N) is a macronutrient essential for plant growth, development and stress resistance. Nevertheless, how nitrate, as an important form of N, affects Cd uptake, translocation and accumulation in sweet sorghum is still unclear. In the present study, a series of nitrate levels (N1, 0.5 mm; N2, 2 mm; N3, 4 mm; N4, 8 mm and N5, 16 mm) with or without added 5 µm CdCl2 treatment in sweet sorghum was investigated hydroponically. The results indicate that Cd accumulation in the aboveground parts of sweet sorghum was enhanced by optimum nitrate supply, resulting from both increased dry weight and Cd concentration. Although root-to-shoot Cd translocation was not enhanced by increased nitrate, some Cd was transferred from cell walls to vacuoles in leaves. Intriguingly, expression levels of Cd uptake and transport genes, SbNramp1, SbNramp5 and SbHMA3, were not closely related to increased Cd as affected by nitrate supply. The expression of SbNRT1.1B in relation to nitrate transport showed an inverted 'U' shape with increasing nitrate levels under Cd stress, which was in agreement with trends in Cd concentration changes in aboveground tissues. Based on the aforementioned results, nitrate might regulate Cd uptake and accumulation through expression of SbNRT1.1B rather than SbNramp1, SbNramp5 or SbHMA3, the well-documented genes related to Cd uptake and transport in sweet sorghum.
Assuntos
Cádmio/metabolismo , Nitratos/metabolismo , Poluentes do Solo/metabolismo , Sorghum/metabolismo , Biodegradação Ambiental , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Raízes de Plantas/metabolismoRESUMO
We show a new resonance acceleration scheme for generating ultradense relativistic electron bunches in helical motions and hence emitting brilliant vortical γ-ray pulses in the quantum electrodynamic (QED) regime of circularly-polarized (CP) laser-plasma interactions. Here the combined effects of the radiation reaction recoil force and the self-generated magnetic fields result in not only trapping of a great amount of electrons in laser-produced plasma channel, but also significant broadening of the resonance bandwidth between laser frequency and that of electron betatron oscillation in the channel, which eventually leads to formation of the ultradense electron bunch under resonant helical motion in CP laser fields. Three-dimensional PIC simulations show that a brilliant γ-ray pulse with unprecedented power of 6.7 PW and peak brightness of 1025 photons/s/mm2/mrad2/0.1% BW (at 15 MeV) is emitted at laser intensity of 1.9 × 1023 W/cm2.
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The dynamics of magnetic reconnection (MR) in the high-energy-density (HED) regime, where the plasma inflow is strongly driven and the thermal pressure is larger than the magnetic pressure (ß>1), is reexamined theoretically and by particle-in-cell simulations. Interactions of two colliding laser-produced plasma bubbles with self-generated poloidal magnetic fields of, respectively, antiparallel and parallel field lines are considered. Through comparison, it is found that the quadrupole magnetic field, bipolar poloidal electric field, plasma heating, and even the out-of-plane electric field can appear in both cases due to the mere plasma bubble collision, which may not be individually recognized as evidences of MR in the HED regime separately. The Lorentz-invariant scalar quantity D(e) ≃ γ(e)j · (E + v(e) × B) (γ(e) = [1-(v(e)/c)(2)](-1/2)) in the electron dissipation region is proposed as the key sign of MR occurrence in this regime.
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A scheme for enhanced quantum electrodynamics (QED) production of electron-positron-pair plasmas is proposed that uses two ultraintense lasers irradiating a thin solid foil from opposite sides. In the scheme, under a proper matching condition, in addition to the skin-depth emission of γ-ray photons and Breit-Wheeler creation of pairs on each side of the foil, a large number of high-energy electrons and photons from one side can propagate through it and interact with the laser on the other side, leading to much enhanced γ-ray emission and pair production. More importantly, the created pairs can be collected later and confined to the center by opposite laser radiation pressures when the foil becomes transparent, resulting in the formation of unprecedentedly overdense and high-energy pair plasmas. Two-dimensional QED particle-in-cell simulations show that electron-positron-pair plasmas with overcritical density 10(22) cm(-3) and a high energy of 100s of MeV are obtained with 10 PW lasers at intensities 10(23) W/cm(2), which are of key significance for laboratory astrophysics studies.
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The intermediate in the preparation of 1,3,7, 10-tetrahydroxybenzo[b]naphtho[2,3-d]furan-6,11-dione (2), 2-chloro-5,8-dimethoxy-3-(3,5-dimethoxyphenoxy)-1,4-naphthoquinone (8h), and corresponding hydroxyl, methoxyl, and acetoxyl analogues was found to possess interesting inhibitory activities in a number of cytotoxic test systems. Activities were also noticed in some 5, 8-dihydroxy-1,4-naphthoquinone derivatives. A structure-activity discussion of compounds of this series is presented. The newly uncovered biological activity of 2-chloro-3-(substituted phenoxyl)-1, 4-naphthoquinones and 2,3-bis(substituted phenoxy)-1, 4-naphthoquinones may suggest an approach for the development of new classes of antineoplastic agents.