The HDAC/HSP90 Inhibitor G570 Attenuated Blue Light-Induced Cell Migration in RPE Cells and Neovascularization in Mice through Decreased VEGF Production

Age-related macular degeneration (AMD) occurs due to an abnormality of retinal pigment epithelium (RPE) cells that leads to gradual degeneration of the macula. Currently, AMD drug pipelines are endowed with limited options, and anti-VEGF agents stand as the dominantly employed therapy. Despite the proven efficacy of such agents, the evidenced side effects associated with their use underscore the need to elucidate other mechanisms involved and identify additional molecular targets for the sake of therapy improvement. The previous literature provided us with a solid rationale to preliminarily explore the potential of selective HDAC6 and HSP90 inhibitors to treat wet AMD. Rather than furnishing single-target agents (either HDAC6 or HSP90 inhibitor), this study recruited scaffolds endowed with the ability to concomitantly modulate both targets (HDAC6 and HSP90) for exploration. This plan was anticipated to accomplish the important goal of extracting amplified benefits via dual inhibition (HDAC6/HSP90) in wet AMD. As a result, G570 (indoline-based hydroxamate), a dual selective HDAC6-HSP90 inhibitor exerting its effects at micromolar concentrations, was pinpointed in the present endeavor to attenuate blue light-induced cell migration and retinal neovascularization by inhibiting VEGF production. In addition to the identification of a potential chemical tool (G570), the outcome of this study validates the candidate HDAC6-HSP90 as a compelling target for the development of futuristic therapeutics for wet AMD.     

原位合成钴/还原氧化石墨烯纳米粒子催化氨硼烷制氢

采用简单的原位还原合成方法,利用具有温和还原性能的氨硼烷作为还原剂,在室温下一步还原氧化石墨烯和氯化钴混合溶液制备了还原氧化石墨烯负载钴纳米复合材料催化剂. 利用所制备的钴/还原氧化石墨烯催化剂催化氨硼烷水解制氢,发现钴/还原氧化石墨烯具有优异的催化性能. 相对于没有负载的钴纳米粒子以及采用硼氢化钠作为还原剂制备的钴/还原氧化石墨烯催化剂,采用氨硼烷还原制备的钴/还原氧化石墨烯催化剂表现出更加优越的催化性能. 动力学测试表明,钴/还原氧化石墨烯催化氨硼烷水解反应为零级反应,同时钴/还原氧化石墨烯催化剂催化氨硼烷水解反应的活化能为27.10 kJ·mol^-1,低于大部分已报道的其它催化剂,甚至一些贵金属催化剂的活化能. 钴/还原氧化石墨烯催化剂有着稳定的循环使用性,特别是其具有的磁性使得它能够直接从溶液中通过磁力回收,极具应用前景. 这种简单有效的合成方法有望推广到其它的金属-还原氧化石墨烯纳米复合材料体系.     

Photocatalytic reduction of carbon dioxide with water using InNbO4 catalyst with NiO and Co3O4 cocatalysts

InNbO₄ was prepared by the solid-state reaction method. Various cocatalysts were added on InNbO₄ by the incipient-wetness impregnation method. The effects of co-catalyst and pretreatment conditions on the photocatalytic activity of InNbO₄ for photoreduction of carbon dioxide were investigated. NiO–InNbO₄ and Co₃O₄–InNbO₄ were pretreated by reduction at 500 °C for 2 h and subsequent oxidation at 200 °C for 1 h. The catalysts were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectroscopy. The characterization results of NiO–InNbO₄ catalysts after pretreatment showed the presence of highly crystalline NiO and monoclinic Nb₂O₅. NiO–InNbO₄ with reduction–oxidation pretreatment exhibited the highest activity due to the presence of core–shell type Ni⁰ and NiO on the surface and the presence of a small amount of Nb₂O₅ as a promoter.     

Banach空间中一类度量投影的判据及表达式

X为自反、严格凸Ｂａｎａｃｈ 空间,L为X中闭子空间,P：X→L为单值算子,该文给出P成为L上度量投影P_L的判据及P_L为线性算子的充分必要条件．在自反Ｂａｎａｃｈ空间中,利用对偶映射,给出超平面上（值）度量投影的表达式．对于自反、严格凸、光滑的Ｂａｎａｃｈ 空间中线性流形上的（单值）度量投影,利用广义右逆的表示,求出其表达式．在后继文章中将给出此表达式的应用．     

Effects of Preparation Parameters on the Characteristics of NiPxBY Nanomaterials

A series of NiP _x B _y nanomaterials were prepared by a chemical reduction method under various preparation parameters. Experiment results show that the different preparation parameters affected the morphology, particle size, surface area and the composition of the sample. However, they did not influence the electronic state of nickel. The type of solution showed significant influence on the properties of the sample, whereas, the type of nickel salt did not. The particle size of NiPB, NiB, and NiP were 10–30 nm. The NiP sample prepared in the aqueous solution had the largest particle size 50–150 nm. If the solvent was 50% ethanol in water, the surface area of the sample significantly increased nine fold for NiP and four fold for NiPB powders. In contrast, the surface area of NiB did not increase. The NiPB, NiB, and NiP powders had a spherical morphology if they were prepared with aqueous solution. The NiPB prepared in 50% ethanol solution showed floss morphology and had a very high surface area.     

Carbon Dioxide Reforming of Methane to Synthesis Gas Over Ni/MgO-Al2O3-AlPO4 Catalysts

Carbon dioxide reforming of methane to synthesis gas was studied over Ni/MgO-Al₂O₃-AlPO₄ catalysts. The conventional Ni/Al₂O₃ and Ni/MgO-Al₂O₃ catalysts were included for comparison. These catalysts were characterized by nitrogen adsorption and hydrogen chemisorption. The results show that Ni/MgO-Al₂O₃-AlPO₄ was more active than the other two catalysts especially at high reaction temperatures. MgO-Al₂O₃-AlPO₄ has a large pore diameter with a very uniform pore size distribution. It can overcome the pore diffusion effect under high temperature reaction conditions.     

溴元素发现史上的成功和遗憾及其历史意义

1826年,法国青年化学家巴拉尔宣布发现了溴元素.然而,同时期的德国化学家李比希、洛威等人面对相似的实验现象与溴元素的发现失之交臂.溴元素的发现使卤族基本成型,增强了科学家验证氟元素假说的信心,并促进了元素周期律的发现.同时,溴元素的发现过程彰显了批判精神和直觉思维对于科学发现的重要作用,说明了科学态度是从事科学研究的...     

Stimulated emission cross sections and temperature-dependent spectral shifts of neutral nitrogen-vacancy centers in diamonds

The neutral nitrogen-vacancy (NV⁰) defects in diamond are photostable color centers, suitable for a wide range of applications in science and engineering. However, the photophysical properties of the centers have not yet been fully characterized. This work measured the stimulated emission cross sections of NV⁰ in a single-crystal diamond by two-photon excitation of its matrix at 344 nm. From the measured photoluminescence spectrum and the fluorescence lifetime of 20 ± 1 ns, we determined a peak stimulated emission cross section of 1.43 ± 0.07 × 10⁻¹⁷ cm² at 650 nm for the NV⁰ centers. In addition, we have also examined the thermal shifts of the zero-phonon line of NV⁰ centers in nanoscale diamonds (~100 nm in diameter) over the temperature range of 30–120°C. A temperature measurement sensitivity of 0.2 K·Hz^−1/2 was achieved, which is about two-fold better than that of NV⁻, despite that the fluorescence intensity of NV⁰ is about six-fold lower than that of NV⁻ in the same nanoparticles. The result is attributed to the smaller electron–phonon coupling strength of the neutral center, compared with its negatively charged counterpart.