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31.
B-cell receptor activation induces BIC/miR-155 expression through a conserved AP-1 element 总被引:3,自引:0,他引:3
Yin Q Wang X McBride J Fewell C Flemington E 《The Journal of biological chemistry》2008,283(5):2654-2662
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Jian-Ping Liu Xiang Zhai Ling-Ling Wang Hong-Ju Li Fang Xie Qi Lin Sheng-Xuan Xia 《Plasmonics (Norwell, Mass.)》2016,11(3):703-711
A graphene-based cylindrical hybrid surface plasmon polariton waveguide, composed of a silicon nanowire core surrounded by a silica layer and then a graphene layer, is investigated using the finite-difference time-domain method. The analytical solutions and the numerical simulation show that an ultra-small mode area and a large propagation length can be achieved with this waveguide. Utilizing the perturbation theory of coupled mode, we demonstrate that the six lowest-order coupling modes originate from the coupling of the three lowest-order single-waveguide modes, and the m?=?1 order yy-coupling mode possesses the maximum coupling length and the minimum crosstalk. This waveguide can be used for photonic integrated circuits in the mid-infrared range. 相似文献
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Liming Yan Yiqi Luo Rebecca A. Sherry Jesse E. Bell Xuhui Zhou Jianyang Xia 《Global Change Biology Bioenergy》2014,6(5):556-565
The efficiency of a terrestrial ecosystem to use rainfall in production is critical in regulating the ecological functions of the earth system under global change. However, it remains unclear how rain use efficiency (RUE) will be altered by changes in climate and human activities such as biofuel harvest. In this study, we used RUE data from a long‐term experiment in a tallgrass prairie to analyze the effects of warming and biofuel harvest (clipping). From 2000 to 2011, experimental warming enhanced RUE in most years, with larger positive effects in normal and wet than dry hydrological years. Clipping decreased RUE in dry and normal hydrological years, but had no impact on RUE in wet years. The observed RUE responses resulted from treatment‐induced changes in both biologically ineffective (i.e., runoff and soil evaporation) and effective (i.e., transpiration) parts of precipitation. For example, litter cover was increased in warming plots, but reduced by clipping, leading to negative and positive effects on runoff and soil evaporation, respectively. The dominance of C4 species, which usually have higher water use efficiency than C3 species, was enhanced by warming, but reduced by clipping. Moreover, RUE was positively correlated with ratios of rainfall in the late growing season (June–August), when the growth of C4 plants was most active, relative to that in the other seasons. Our results indicate that RUE is positively influenced by climate warming, but negatively affected by biofuel harvest in tallgrass prairie of the Great Plains. These findings highlight the important roles of plant community structure and temporal distribution of precipitation in regulating ecosystem RUE. 相似文献
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Natalia J. Martinez Ganesha Rai Adam Yasgar Wendy A. Lea Hongmao Sun Yuhong Wang Diane K. Luci Shyh-Ming Yang Kana Nishihara Shunichi Takeda Mohiuddin Irina Earnshaw Tetsuya Okada Kazutoshi Mori Kelli Wilson Gregory J. Riggins Menghang Xia Maurizio Grimaldi Ajit Jadhav David J. Maloney Anton Simeonov 《PloS one》2016,11(11)
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Wei Guo Wenfeng Liu Lingjian Zhu Yongqiang Zhang Pengfei Cheng Guoqiang Dong Chunlin Zhuang Jianzhong Yao Chunquan Sheng Zhenyuan Miao Wannian Zhang 《化学与生物多样性》2011,8(8):1539-1549
Homocamptothecin (hCPT) is an E‐ring modified camptothecin (CPT) analogue, which showed pronounced inhibitory activity of topoisomerase I. In search of novel hCPT‐type anticancer agents, two series of hCPT derivatives were synthesized and evaluated in vitro against three human tumor cell lines. The results indicated that the 10‐substituted hCPT derivatives had a considerably higher cytotoxic activity than the 12‐substituted ones. Among the 10‐substituted compounds, 8a, 8b, 9b , and 9i showed an equivalent or even more potent activity than the positive control drug topotecan against the lung cancer cell line A‐549. Moreover, the hCPT analogues 8a and 8b exhibited a higher topoisomerase I inhibitory activity than CPT at a concentration of 100 μM . 相似文献
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Jun Feng Lu Meng Qing Zhu Bao Cai Xie Xiao Chen Shi Huan Liu Rui Xin Zhang Bo Xia Jiang Wei Wu 《PLoS biology》2022,20(2)
Elevated circulating levels of growth differentiation factor 15 (GDF15) have been shown to reduce food intake and lower body weight through activation of hindbrain receptor glial-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL) in rodents and nonhuman primates, thus endogenous induction of this peptide holds promise for obesity treatment. Here, through in silico drug-screening methods, we found that small molecule Camptothecin (CPT), a previously identified drug with potential antitumor activity, is a GDF15 inducer. Oral CPT administration increases circulating GDF15 levels in diet-induced obese (DIO) mice and genetic ob/ob mice, with elevated Gdf15 expression predominantly in the liver through activation of integrated stress response. In line with GDF15’s anorectic effect, CPT suppresses food intake, thereby reducing body weight, blood glucose, and hepatic fat content in obese mice. Conversely, CPT loses these beneficial effects when Gdf15 is inhibited by a neutralizing antibody or AAV8-mediated liver-specific knockdown. Similarly, CPT failed to reduce food intake and body weight in GDF15’s specific receptor GFRAL-deficient mice despite high levels of GDF15. Together, these results indicate that CPT is a promising anti-obesity agent through activation of GDF15-GFRAL pathway.Elevated circulating levels of growth differentiation factor 15 (GDF15) have been shown to reduce food intake and lower body weight in rodents and nonhuman primates. This study reveals that the small molecule Camptothecin induces endogenous GDF15, suppressing food intake and reducing body weight in obese mice, suggesting a promising candidate for anti-obesity treatment. 相似文献
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