105 research outputs found

    Methyl 4-methyl­sulfonyl-2-nitro­benzoate

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    The title compound, C9H9NO6S, was prepared by the reaction of methanol and thionyl chloride with 4-methyl­sulfonyl-2-nitro­benzoic acid under mild conditions. The dihedral angle between the nitro group and benzene ring is 21.33 (19)° and that between the carboxyl­ate group and the benzene ring is 72.09 (17)°. The crystal structure is stabilized by weak inter­molecular bifurcated C—H⋯O inter­actions occurring in the (100) plane

    Ethyl N-[3-(N,N-dimethyl­carbamo­yl)pyridin-2-ylsulfon­yl]carbamate

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    In the mol­ecular structure of the title compound, C11H15N3O5S, the amide group is nearly perpendicular to the pyridine ring, making a dihedral angle of 86.30 (13)°. The terminal ethyl group is disordered over two sites of equal occupancy. Inter­molecular N—H⋯O hydrogen bonding is present in the crystal structure

    北沙参茎叶提取物对小鼠半数溶血值(HC50)的影响

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    Objective: To study the effect of Umbelliferae littoralis leaf extract on the Hemolytic Value (HC50) of mice, and to provide the basis for the development and utilization medicinal resources and edible resources. Methods: Prepare littoralis leaf water extract and alcohol extract, and set different dose treatment groups and blank control group, and continuously deliver American ginseng capsule for 15 days. Inject sRBC according to the weight on the tenth day. Take the blood serum from eyeball blood after 5 days. Put supernatant of 1ml and Dulbecco's reagent of 3ml in the test tube, and mix the 10% sRBC of 0.25ml and Dulbecco's reagent of 4ml together in another test tube, and measure absorbance at 540nm fine control (SA liquid) tubing as blank, HC50 value were calculated. Results: Different extracts of stems and littoralis leaf were given to the mice for 15 days, and hemolytic value of the mice in water extract 4.68g/kg dose group, alcohol extract 4.68g/kg dose group and American ginseng capsule group significantly increased while comparing with the blank control group (P<0.05). Conclusion: Littoralis Leaf plays an important role in regulating human immunity.目的  研究伞形科植物北沙参茎叶提取物对小鼠半数溶血值(HC50)的影响,为扩大药用资源和食用资源及开发利用提供依据。 方法  制备北沙参茎叶水提取物和醇提取物,设置给药组的不同剂量与空白对照组、西洋参胶囊组连续给药15天,第10天按体重注射 sRBC。5天后取眼球血分离血清。取上清液1ml和都氏试剂3ml于试管内,同时取10% sRBC 0.25ml,加都氏试剂至4ml,于另一支试管内充分混匀,于540nm处以对照(SA液)管作空白,测定吸光度值计算HC50。 结果  经口给予小鼠不同剂量的北沙参茎叶提取物15天,与对照组比较,水提取物4.68g/kg剂量组、醇提取物4.68g/kg剂量组、西洋参胶囊组小鼠半数溶血值明显升高(P<0.05)。 结论  北沙参茎叶具有调节体液免疫的作用

    Deformation and Failure Mechanism of the Lower Roadway in a Close-Range Residual Coal Pillar Area

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    The Tashan coal mine is selected as a case study to determine the deformation and damage mechanisms of the lower roadway in a close-range residual coal pillar area. Roof drilling peephole technology is applied to detect the damage to the roadway roof surrounding rock. A boundary invisibility equation is derived for the plastic zone of a circular hole based on the theory of a butterfly plastic zone in a non-uniform stress field in which the principal stress occurs at an arbitrary angle to the vertical. Maple mathematical drawing software is combined with FLAC3D numerical simulations to investigate the influence of the principal stress ratio and direction on the roadway plastic zone. The results indicate that the plastic zone of the roadway surrounding rock assumes a butterfly shape when the bidirectional stress ratio is large, and the direction of the butterfly-shaped failure of the roadway is related to the principal stress direction. Field test images are combined to show that the asymmetric damage pattern of the lower roadway in a close-range residual coal pillar area is influenced by the presence of the roadway in a non-uniform stress field in which the main stress direction is deflected

    Adaptation of a visualized loop-mediated isothermal amplification technique for field detection of Plasmodium vivax infection

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    <p>Abstract</p> <p>Background</p> <p>Loop-mediated isothermal amplification (LAMP) is a high performance method for detecting DNA and holds promise for use in the molecular detection of infectious pathogens, including <it>Plasmodium </it>spp. However, in most malaria-endemic areas, which are often resource-limited, current LAMP methods are not feasible for diagnosis due to difficulties in accurately interpreting results with problems of sensitive visualization of amplified products, and the risk of contamination resulting from the high quantity of amplified DNA produced. In this study, we establish a novel visualized LAMP method in a closed-tube system, and validate it for the diagnosis of malaria under simulated field conditions.</p> <p>Methods</p> <p>A visualized LAMP method was established by the addition of a microcrystalline wax-dye capsule containing the highly sensitive DNA fluorescence dye SYBR Green I to a normal LAMP reaction prior to the initiation of the reaction. A total of 89 blood samples were collected on filter paper and processed using a simple boiling method for DNA extraction, and then tested by the visualized LAMP method for <it>Plasmodium vivax </it>infection.</p> <p>Results</p> <p>The wax capsule remained intact during isothermal amplification, and released the DNA dye to the reaction mixture only when the temperature was raised to the melting point following amplification. Soon after cooling down, the solidified wax sealed the reaction mix at the bottom of the tube, thus minimizing the risk of aerosol contamination. Compared to microscopy, the sensitivity and specificity of LAMP were 98.3% (95% confidence interval (CI): 91.1-99.7%) and 100% (95% CI: 88.3-100%), and were in close agreement with a nested polymerase chain reaction method.</p> <p>Conclusions</p> <p>This novel, cheap and quick visualized LAMP method is feasible for malaria diagnosis in resource-limited field settings.</p

    Preparations and Electrochemical Properties of BC/CoNi2S4@PPy Flexible Composites for Supercapacitors

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    本文采用溶剂热、原位聚合和真空抽滤相结合的方法制备了用于超级电容器的细菌纤维素/镍钴硫化物/聚吡咯(BC/CoNi2S4@PPy)柔性电极材料,通过X射线衍射、场发射扫描电镜、红外光谱、氮气吸脱附、拉伸强度和接触角表征了材料的形貌结构、组成、机械性能和亲水性,并采用循环伏安法和恒电流充放电测试了复合材料的电化学性能。结果表明,表面含氧官能团丰富的BC纤维网络结构对氧化还原活性物质CoNi2S4的生长和导电聚合物PPy的分布具有引导作用,CoNi2S4均匀分布在BC网络中,且PPy均匀包覆在BC纤维和CoNi2S4纳米球表面构成具有丰富孔隙结构的三维导电网络,使得该复合材料具有较好的机械性(抗拉强度达28.0±0.1 MPa)、亲水性(对6 mol·L-1 KOH的瞬间接触角为43.6°)及良好的导电性。该电极材料在1 A·g-1下比电容高达2670 F·g-1,充放电循环10000次后比电容的保持率为82.73%,且经1000次反复弯曲后电化学性能保持不变。此外,将其与活性炭组成的非对称超级电容器,在1 A·g-1下比电容为1428 F·g-1,最高能量密度和功率密度分别达49.8 Wh·kg-1和741.8 W·kg-1。Flexible supercapacitor is one of the most promising energy storage devices for portable and wearable electronic products due to its advantages of high power density, fast charging and long cycle life. Therefore, self-supporting flexible electrode materials with high performance have attained more and more attention both in academia and in industry recently. In this work, using bacterial cellulose (BC) as a flexible substrate, the bacterial cellulose/nickel-cobalt sulfide@polypyrrole (BC/CoNi2S4@PPy) flexible composites with three-dimensional porous network and good conductivity were prepared by a combined solvothermal-in-situ polymerization-vacuum filtration method. The samples were characterized by X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectrometry, N2 physisorption, tensile strength and contact angle measurements. Their electrochemical performances were tested by cyclic voltammetry, galvanostatic charge/discharge testing and electrochemical impedance spectroscopy. The results show that the three-dimensional porous network of BC fibers with rich oxygen-containing surface groups play a guiding role in the growth of the redox active material CoNi2S4 and the distribution of conductive polymer PPy, resulting in uniformly distributed CoNi2S4 nanospheres in the network of BC fibers, both coated evenly with a layer of conductive PPy. The resulting BC/CoNi2S4@PPy composites, a three-dimensional conductive network with high porosity, displayed good mechanical property (tensile strength up to 28.0±0.1 MPa), hydrophilicity (the instantaneous contact angle in 6 mol·L-1 KOH is 43.6°), as well as excellent electrochemical performance. The specific capacitance of the flexible BC/CoNi2S4@PPy was 2670 F·g-1 at 1 A·g-1 in a three-electrode system, and retained 82.7% after 10000 charge and discharge cycles. In addition, the electrochemical performance remained unchanged after 1000 times of repeated bending. In an asymmetric supercapacitor composed of BC/CoNi2S4@PPy and activated carbon, the area specific capacitance was 1428 F·g-1 at 1 A·g-1. The asymmetric supercapacitor achieved the maximum energy density of 49.8 Wh·kg-1 and power density of 741.8 W·kg-1.国家重点基础研究发展计划项目(2014CB239702);国家自然科学基金项目(21676082)通讯作者:周静红E-mail:[email protected]:Jing-HongZhouE-mail:[email protected]华东理工大学化工学院,上海 200237School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, Chin

    Neuroprotectants attenuate hypobaric hypoxia-induced brain injuries in cynomolgus monkeys

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    Hypobaric hypoxia (HH) exposure can cause serious brain injury as well as life-threatening cerebral edema in severe cases. Previous studies on the mechanisms of HH-induced brain injury have been conducted primarily using non-primate animal models that are genetically distant to humans, thus hindering the development of disease treatment. Here, we report that cynomolgus monkeys (Macaca fascicularis) exposed to acute HH developed human-like HH syndrome involving severe brain injury and abnormal behavior. Transcriptome profiling of white blood cells and brain tissue from monkeys exposed to increasing altitude revealed the central role of the HIF-1 and other novel signaling pathways, such as the vitamin D receptor (VDR) signaling pathway, in co-regulating HH-induced inflammation processes. We also observed profound transcriptomic alterations in brains after exposure to acute HH, including the activation of angiogenesis and impairment of aerobic respiration and protein folding processes, which likely underlie the pathological effects of HH-induced brain injury. Administration of progesterone (PROG) and steroid neuroprotectant 5α-androst-3β,5,6β-triol (TRIOL) significantly attenuated brain injuries and rescued the transcriptomic changes induced by acute HH. Functional investigation of the affected genes suggested that these two neuroprotectants protect the brain by targeting different pathways, with PROG enhancing erythropoiesis and TRIOL suppressing glutamate-induced excitotoxicity. Thus, this study advances our understanding of the pathology induced by acute HH and provides potential compounds for the development of neuroprotectant drugs for therapeutic treatment
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