A hypoxia-activated NO donor for the treatment of myocardial hypoxia injury

As present NO donor drugs cannot localize to release NO at the hypoxic site, along with the short half-life and bidirectional regulation of NO, they are unable to overcome low bioavailability and side effects in the treatment of myocardial hypoxia injury. In this study, we designed and prepared a novel hypoxia-activated NO donor (Hano) by hybridization of a known NO donor compound (Nno) with a hypoxia-activated group. Hano and isosorbide dinitrate were compared in terms of NO release and anti-myocardial hypoxia injury. Furthermore, the effects of Hano and Nno on releasing NO, dilating blood vessels, and preventing myocardial hypoxia injury were studied and compared in smooth muscle cells, cardiomyocytes and mice. The results showed that the NO release by Hano increased either in smooth muscle cells or in myocardial cells under hypoxia conditions. Significantly, Hano was found capable of dilating blood vessels and attenuating hypoxia injury both in vitro and in vivo, and has great potential as a hypoxia-activated NO donor drug to treat hypoxic heart diseases.

A novel HAP-type NO donor was found to release NO under hypoxia locally. It dilates blood vessels in smooth muscle cells and attenuates myocardial hypoxia injury in cardiomyocytes.     

高效液相色谱-蒸发光散射检测法直接检测20种未衍生基本氨基酸

应用国产蒸发光散射检测器(ELSD),建立了一种采用反相高效液相色谱-蒸发光散射检测器(RHPLC-ELSD)直接测定20种未衍生基本氨基酸的分析方法,并将其用于氨基酸注射液中氨基酸含量的测定。采用BISCHOFFTM　C18 AQ PLUS色谱柱(250 mm×4.6 mm, 5 μm)分离,以甲醇-0.2%七氟丁酸溶液(含0.1%三氟乙酸)为流动相进行梯度洗脱,流速0.8 mL/min,ELSD飘移管温度40 ℃,载气流量2.5 L/min,对20种基本氨基酸进行分离检测。氨基酸的质量浓度在30～300 mg/L范围内,其峰面积的对数值与进样质量的对数值呈良好的线性关系;氨基酸的检出限(信噪比(S/N)＞3)介于24 ～100 ng之间,样品加标回收率为90.6%～106.0%。结果表明,该系统及方法操作简便快速、准确可靠,无需依靠专门的氨基酸分析仪或衍生处理氨基酸即可直接测定氨基酸注射液中氨基酸含量,为药品、食品及化工生产等领域混合氨基酸样品的直接检测提供了参考。     

The in situ investigation of the polyaniline-derived N-doped carbon with the interdigitated array electrodes towards the oxygen reduction reaction

Journal of Solid State Electrochemistry - Nowadays, tremendous effort has been made in searching clean, high-efficient and sustainable energy, and related energy conversion methods. Oxygen...     

Identification of prototypes from Ligustri Lucidi Fructus in rat plasma based on a data-dependent acquisition and multicomponent pharmacokinetic study

The identification and quantization of traditional Chinese medicine (TCM) are a challenge for researchers and industry. Using untargeted analytical methods, the in vivo detection and identification of TCM compounds are difficult because of the significant interference of endogenous substances. Fortunately, the ongoing development of new analytical technologies, especially Q-Orbitrap–MS, offers some solutions. Our team developed a holistic MS method, combining untargeted data-dependent MS² (dd-MS²) modes to extensively identify TCM prototypes in vivo. The method was successfully applied to the analysis of Ligustri Lucidi Fructus (LLF). LLF is a widely used TCM with a remarkable nourishing effect on the liver and kidney. In the study, we aimed to identify the prototypes in rat plasma after oral administration of LLF extract. Following separation on an HSS T₃ column, LLF extract and rat plasma were performed in untargeted dd-MS² mode. Forty-seven compounds were characterized in rats plasma as prototypes of LLF extract. Furthermore, seven major prototypes were chosen as pharmacokinetic markers to investigate LLF's pharmacokinetic properties. The results provides comprehensive determination of compounds in LLF both in vitro and in vivo, which is important for quality control, pharmacology studies and clinical use of LLF.     

Mössbauer study of the effect of potassium on iron oxide catalysts

One kind of catalyst used for dehydrogenation of ethylbenzene to styrene was investigated by⁵⁷Fe Mössbauer spectroscopy. The results show that the area ratioS _B /S _A of two Mössbauer subspectra of Fe_3-vO₄ produced after catalytic reaction depends on the amounts of potassium added to the catalysts. A tentative conclusion is that the effect of potassium in iron oxide catalysts could be related to the reduction of Fe³⁺ to Fe²⁺.     

EXISTENCE OF WEAK SOLUTIONS TO A p-LAPLACIAN PROBLEM INVOLVING DIRICHLET BOUNDARY CONDITION

In this paper, by virtue of Leray-Lions theorem, we are mainly concerned with the existence of weak solutions to a Dirichlet boundary value problem with the p-Laplacian operator.     

Effect of spatial refractive-index nonuniformities existed in a large-scale rapid growth KDP crystal on third-harmonic conversion

Effect of spatial refractive-index nonuniformities existed in a large-scale rapid growth KDP crystal (a type I frequency doubler at the wavelength of 1053 nm) on third-harmonic conversion is studied. Spatial refractive-index nonuniformities due to imperfections in the crystal structure which prohibit the attainment of phase matching at all locations in the crystal are measured with the orthogonal polarization interferometry technique. And a third-harmonic conversion experiment is conducted on a large-scale facility to investigate the influence of refractive-index nonuniformities on conversion efficiency and third-harmonic beam nearfield. According to the experimental results, refractive-index nonuniformities in this large-scale rapid growth KDP doubler do not reduce the third-harmonic conversion efficiency, but affect the third-harmonic beam nearfield.     

Network analyses for transmission characteristics of several kinds of curve-shaped groove waveguides

In this paper, the several kinds of the novel curve-shaped groove guides including the whole elliptic-, whole cosine- and hyperbolic-groove guides as the new millimeter wave transmission lines are presented. The dispersion, cut-off and band characteristics of the dominant mode for the several kinds of the curve-shaped groove guides are analysed by using the equivalent network method with transverse resonance. The obtained results have important values in their theoretical studies and actual applications of the curve-shaped groove waveguides.