Novel indanone derivatives as potential imaging probes for β-amyloid plaques in the brain

Molecular imaging probes to detect senile plaques (SPs) might help the early diagnosis of Alzheimer's disease (AD). In this study, a novel series of indanone derivatives were synthesized and characterized. In in vitro binding studies, compound 2e exhibited a K(i) value of 16 nM with a human AD brain homogenate. Although they displayed relatively low affinities for 2i and 2j--with K(i) values of 99 and 237 nM, respectively--the SPs in AD brain sections were positively stained by 2j. A method for in situ micro-autoradiography of AD brain was developed in this study and showed clear labeling of SPs by [(125)I]2i and [(125)I]2j. Both [(125)I]2i and [(125)I]2j had suitable lipophilicities and displayed high initial uptake and rapid clearance from the mouse brains. Furthermore, [(125)I]2i and [(125)I]2j were more stable in human brain homogenates than in mouse brain homogenates. These data suggest that such indanone derivatives might represent potential amyloid imaging agents for the detection of SPs in AD.     

毫米波辐照下大鼠皮肤温度场及血液灌注率影响研究

根据Pennes方程和毫米波在动物皮肤内的传播特性,建立了在33.5 GHz毫米波同辐照强度下的大鼠皮肤的非稳态多层传热模型. 在二维柱坐标下进行离散计算,得到了长时间辐照条件下不同皮肤深度的温度变化规律,并将理论结果与实验数据进行了比较. 在284 mW/cm2和853 mW/cm2辐照强度下,理论结果和实验结果基本一致; 在474 mW/cm2和664 mW/cm2辐照强度下,有一定的误差,但误差仍不超过1 ℃,验证了该理论模型的准确性.分析了实际趋肤深度内的温度分布,发现毫米波引起的生物热效应的最高温度点并非在皮肤表面,而是皮下某点,其与表面辐照中心点的温差可超过1 ℃.进一步分析了血液灌注率对温度场的影响,发现在讨论的温度范围内,血液灌注率的变化对毫米波辐照下的皮肤表面温度场的影响较小.     

Excitation-induced tunable luminescent properties of polyhedral CaMoO4 microcrystallites

Journal of Materials Science: Materials in Electronics - Polyhedral CaMoO4 microcrystallites with excitation-induced tunable luminescent characteristics were successfully synthesized by a...     

First-Principles Study on Structural,Electronic, and Magnetic Properties of 3d Transition-Metal Nanowires Encapsulated Inside GaN Nanotubes

We have performed the first-principles calculations on the structural, electronic, and magnetic properties of 3d transition-metal nanowires (TMNW₄s), Fe₄, Co₄, and Ni₄, encapsulated inside GaN nanotubes (GaNNTs). The results show that, all three types of the TMNW₄ encapsulated inside the narrower (6,6) and broader (8,8) GaNNTs are both exothermic. The spin polarization and magnetic moment of the TMNW₄@(8,8) systems are larger than those of the TMNW₄@(6,6) systems due to more weak restriction of the broader (8,8) GaNNT, but those of these two combined systems are smaller than those of the corresponding freestanding TMNW₄. Our results reveal that either the TMNW₄@(6,6) or TMNW₄@(8,8) systems have high spin polarization and magnetic moment and stably exist in atmosphere for long time and thus can be expected to have potential applications in building nanodevices.