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991.
The interaction between vascular cells and macrophages is critical during vascular remodeling. Here we report that the scaffolding protein, ezrin-binding phosphoprotein 50 (EBP50), is a central regulator of macrophage and vascular smooth muscle cells (VSMC) function. EBP50 is up-regulated in intimal VSMC following endoluminal injury and promotes neointima formation. However, the mechanisms underlying these effects are not fully understood. Because of the fundamental role that inflammation plays in vascular diseases, we hypothesized that EBP50 mediates macrophage activation and the response of vessels to inflammation. Indeed, EBP50 expression increased in primary macrophages and VSMC, and in the aorta of mice, upon treatment with LPS or TNFα. This increase was nuclear factor-κB (NF-κB)-dependent. Conversely, activation of NF-κB was impaired in EBP50-null VSMC and macrophages. We found that inflammatory stimuli promote the formation of an EBP50-PKCζ complex at the cell membrane that induces NF-κB signaling. Macrophage activation and vascular inflammation after acute LPS treatment were reduced in EBP50-null cells and mice as compared with WT. Furthermore, macrophage recruitment to vascular lesions was significantly reduced in EBP50 knock-out mice. Thus, EBP50 and NF-κB participate in a feed-forward loop leading to increased macrophage activation and enhanced response of vascular cells to inflammation.  相似文献   
992.
The endosomal sorting complex required for transport (ESCRT) is highly conserved in eukaryotic cells and plays an essential role in the biogenesis of multivesicular bodies and cargo degradation to the plant vacuole or lysosomes. Although ESCRT components affect a variety of plant growth and development processes, their impact on leaf development is rarely reported. Here, we found that OsSNF7.2, an ESCRT-III component, controls leaf rolling in rice (Oryza sativa). The Ossnf7.2 mutant rolled leaf 17 (rl17) has adaxially rolled leaves due to the decreased number and size of the bulliform cells. OsSNF7.2 is expressed ubiquitously in all tissues, and its protein is localized in the endosomal compartments. OsSNF7.2 homologs, including OsSNF7, OsSNF7.3, and OsSNF7.4, can physically interact with OsSNF7.2, but their single mutation did not result in leaf rolling. Other ESCRT complex subunits, namely OsVPS20, OsVPS24, and OsBRO1, also interact with OsSNF7.2. Further assays revealed that OsSNF7.2 interacts with OsYUC8 and aids its vacuolar degradation. Both Osyuc8 and rl17 Osyuc8 showed rolled leaves, indicating that OsYUC8 and OsSNF7.2 function in the same pathway, conferring leaf development. This study reveals a new biological function for the ESCRT-III components, and provides new insights into the molecular mechanisms underlying leaf rolling.  相似文献   
993.
A novel series of benzodihydrofuran derivatives was developed as potent MEK inhibitors through scaffold hopping based on known clinical compounds. Further SAR exploration and optimization led to another benzofuran series with good oral bioavailability in rats. One of the compounds EBI-1051 (28d) demonstrated excellent in vivo efficacy in colo-205 tumor xenograft models in mouse and is suitable for pre-clinical development studies for the treatment of melanoma and MEK associated cancers. Compared to AZD6244, EBI-1051 showed superior potency in some cancer cell lines such as colon-205, A549 and MDA-MB-231.  相似文献   
994.
In this work, a hierarchically porous and ultrathick “breathable” wood‐based cathode for high‐performance Li‐O2 batteries is developed. The 3D carbon matrix obtained from the carbonized and activated wood (denoted as CA‐wood) serves as a superconductive current collector and an ideal porous host for accommodating catalysts. The ruthenium (Ru) nanoparticles are uniformly anchored on the porous wall of the aligned microchannels (denoted as CA‐wood/Ru). The aligned open microchannels inside the carbon matrix contribute to unimpeded oxygen gas diffusion. Moreover, the hierarchical pores on the microchannel walls can be facilely impregnated by electrolyte, forming a continuous supply of electrolyte. As a result, numerous ideal triphase active sites are formed where electrolyte, oxygen, and catalyst accumulate on the porous walls of microchannels. Benefiting from the numerous well‐balanced triple‐phase active sites, the assembled Li‐O2 battery with the CA‐wood/Ru cathode (thickness: ≈700 µm) shows a high specific area capacity of 8.58 mA h cm?2 at 0.1 mA cm?2. Moreover, the areal capacity can be further increased to 56.0 mA h cm?2 by using an ultrathick CA‐wood/Ru cathode with a thickness of ≈3.4 mm. The facile ultrathick wood‐based cathodes can be applied to other cathodes to achieve a super high areal capacity without sacrificing the electrochemical performance.  相似文献   
995.
A simplified procedure for the isolation and purification of 124-kDa phytochrome from etiolated Avena seedlings has been developed using the method of ammonium sulfate back-extraction. After hydroxyapatite chromatography of seedling tissue extracts, the pooled phytochrome was subjected to ammonium sulfate back-extraction instead of the usual application to an Affi-Gel Blue column. The resulting phytochrome had specific absorbance ratios (SAR = A666/A280) ranging from 0.85 to 0.95. Subsequent Bio-Gel filtration chromatography yielded highly pure 124-kDa phytochrome with SAR values ranging from 0.99 to 1.13. The absorption maxima of 124-kDa phytochrome were at 280, 379, and 666 nm for the red absorbing form of phytochrome (Pr) and at 280, 400 and 730 nm for the far-red absorbing form (Pfr). The A730/A673 ratio in Pfr was found to be 1.5 to 1.6. The mole fraction of Pfr under red light photoequilibrium was 0.88. No dark reversion was detected within 5 h at 3 degrees C. A photoreversible far-uv-circular dichroism was observable with all phytochrome preparations examined. Fluorescence and phosphorescence lifetimes were measured to further characterize the differences between the phytochromes prepared under different conditions. The Trp fluorescence and phosphorescence lifetimes of Pr and Pfr with the chromophore "X", probably polyphenolic in nature, were significantly shorter than those of phytochrome without the contaminant X. The short lifetime of the fluorescence of the Pr chromophore is attributable to X in the former.  相似文献   
996.
2000年研究了武夷山九曲溪水体的营养状态与原生动物群落结构关系。发现并非水越清洁PFU原生动物种类就越多,这要决定于水体的营养状况。当水体是贫营养时,水越清洁,PFU原生动物种类反而会越少。研究结果表明,即使在低营养水平的水体中,PFU法一样能准确反映人类活动对当地水环境的影响。  相似文献   
997.
Preclinical investigations and early clinical trials suggest that FLT3 inhibitors are a viable therapy for acute myeloid leukemia. However, early clinical data have been underwhelming due to incomplete inhibition of FLT3. We have developed 3-phenyl-1H-5-pyrazolylamine as an efficient template for kinase inhibitors. Structure–activity relationships led to the discovery of sulfonamide, carbamate and urea series of FLT3 inhibitors. Previous studies showed that the sulfonamide 4 and carbamate 5 series were potent and selective FLT3 inhibitors with good in vivo efficacy. Herein, we describe the urea series, which we found to be potent inhibitors of FLT3 and VEGFR2. Some inhibited growth of FLT3-mutated MOLM-13 cells more strongly than the FLT3 inhibitors sorafenib (2) and ABT-869 (3). In preliminary in vivo toxicity studies of the four most active compounds, 10f was found to be the least toxic. A further in vivo efficacy study demonstrated that 10f achieved complete tumor regression in a higher proportion of MOLM-13 xenograft mice than 4 and 5 (70% vs 10% and 40%). These results show that compound 10f possesses improved pharmacologic and selectivity profiles and could be more effective than previously disclosed FLT3 inhibitors in the treatment of acute myeloid leukemia.  相似文献   
998.
Abstract

Novel l-sangivamycin and toyocamycin analogues were synthesized and evaluated for Cdc2 protein kinase activity. Among the compounds tested, l-xylose derivative and l-arabinose derivative exhibited potent inhibitory activity against Cdc2 protein kinase with IC50 values of 3.7 and 1.6 μM, respectively.  相似文献   
999.
根据《国际藻类、菌物和植物命名法规》(深圳法规)规则9.2的精神,对我国25个蕨类植物名称的原白中指定的主模式标本错误做了更正,这些植物名称是粤里白、峨眉里白、云南姬蕨、阔基凤丫蕨、川西蹄盖蕨、无盖蹄盖蕨、贡山蹄盖蕨、哈巴蹄盖蕨、假轴果蹄盖蕨、大盖蹄盖蕨、金佛山蛾眉蕨、城口假冷蕨、墨脱红线蕨、镰羽复叶耳蕨、离脉柳叶蕨、弓羽柳叶蕨、木坪贯众、秦岭贯众、强壮鳞毛蕨、西天目鳞毛蕨、百山祖鳞毛蕨、离柄沙皮蕨、毛根蕨、长柄线蕨和长瓦韦。  相似文献   
1000.
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