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991.
992.
Jianmei Luo Meiling Chi Hongyu Wang Huanhuan He Minghua Zhou 《Bioprocess and biosystems engineering》2013,36(12):1889-1896
A convenient and promising alternative to surface modification of carbon mesh anode was fulfilled by electrochemical oxidation in the electrolyte of nitric acid or ammonium nitrate at ambient temperature. It was confirmed that such an anode modification method was low cost and effective not only in improving the efficiency of power generation in microbial fuel cells (MFCs) for synthetic wastewater treatment, but also helping to reduce the period for MFCs start-up. The MFCs with anode modification in electrolyte of nitric acid performed the best, achieving a Coulombic efficiency enhancement of 71 %. As characterized, the electrochemical modification resulted in the decrease of the anode potential and internal resistance but the increase of current response and nitrogen-containing and oxygen-containing functional groups on the carbon surface, which might contribute to the enhancement on the performances of MFCs. 相似文献
993.
Haiyang He Zhirong Mou Wanling Li Lei Fei Yan Tang Ji Zhang Ping Yan Zhengqiong Chen Xia Yang Zigang Shen Jintao Li Yuzhang Wu 《Proteomics》2013,13(7):1121-1132
Rotavirus (RV) infection is the main cause of acute dehydrating diarrhea in infants and young children below 5 years old worldwide. RV infection causes a global shutoff of host proteins as many other viruses do. However, previous studies revealed that RV could selectively upregulated the expression of some host proteins that then played important roles in RV infection. To globally explor such host proteins that were upregulated in early human rotavirus (HRV) infection, proteomic methods were used and a total of ten upregulated host proteins were unambiguously identified. Cyclophilin A (CYPA), a peptidyl‐prolyl cis‐trans isomerase, was among these upregulated host proteins. Following infection, CYPA was recruited to the viroplasm and interacted with HRV structural protein VP2; CYPA reduced host susceptibility to HRV infection and inhibited replication of HRV by repressing the expression of viral proteins. Furthermore, we found that the increased expression of CYPA in enterocytes of small intestine correlated to the period when BALB/c mice became resistant to RV diarrhea. Together, we identified CYPA as a novel host restriction factor that confered protection against RV infection and might contribute to host susceptibility to RV diarrhea. 相似文献
994.
995.
目的:已经有研究证明肝再生磷酸酶3(PhosphataseofRegeneratingLiver-3,PRL-3)在消化道肿瘤的发生发展过程中起到重要作用,但其在膀胱癌中发挥何种作用尚不清楚,本次研究主要探寻PRL-3在膀胱癌细胞T24中作用,以求为膀胱癌的治疗提供新思路。方法:采用siRNA干涉的方法下调T24中PRL-3蛋白表达水平,通过westernblot方法检测干涉效果,绘制细胞生长曲线、构建裸鼠种植瘤模型,检测PRL-3下调对细胞体外及体内增殖的影响。结果:我们所设计的siRNA能够下调PRL-3在A498细胞中的表达(F=7.26,P〈0.05),细胞生长曲线显示下调PRL-3能够抑制细胞的增殖,这种作用从干涉后的第60h开始,随时间增加作用愈加明显(F≥8.35,P〈0.05);动物实验表明,siRNA下调PRL-3能够抑制T24细胞在活体内的增殖,从干涉后第21天开始这种作用开始体现出来(F≥10.46,P〈0.05),并且干涉组的肿瘤肿瘤明显低于两个对照组(F=13.63,P〈0.05)。结论:我们构建的siRNA能够在T24细胞中实现对PRL.3蛋白的下调,siRNA介导的PRL-3蛋白下调能够明显抑制T24细胞在活体外及活体内的增殖,这初步证明PRL-3在膀胱癌中发挥重要的作用。随着我们对PRL-3分子进一步深入的了解,揭示其发挥作用的具体机制,PRL-3很可能成为膀胱癌基因治疗的新靶点。 相似文献
996.
Jie Zhou Changtao Wang Zeyu Zhao Yanqin Wang Jiayu He Xing Tao Xiangang Luo 《Plasmonics (Norwell, Mass.)》2013,8(2):1073-1078
Ag tip–insulator–metal structure with bottom–up light illumination is proposed and theoretically analyzed. It shows that there is a strong plasmonic coupling between Ag tip and metallic surface. Different from oblique light illumination, this novel design possesses unique advantages of symmetrical hot spot profile and enlarged depth of focus at a sub-10-nm spatial resolution. Influences of tip size, insulator, and metallic layer thickness are studied. It is found that the metallic layer thickness greatly affects the plasmonic hot spot quality. Meanwhile, the thickness of photoresist plays a major role in controlling light spot size, indicating that much higher resolution can be achieved for the Ag tips with large curvature radius. 相似文献
997.
We theoretically investigate the plasmonic Fano resonance in a triangular nanoprism dimer. By adjusting the geometry parameters, we have observed a Fano line shape in the scattering spectra, which is induced by the competence of bonding and antibonding modes in the triangular nanoprism dimer. The Fano line shape can be well described by a theoretical model of two harmonic oscillators. A figure of merit value as high as 16.1 is achieved in the triangular nanoprism dimer, which is caused by the Fano resonance. The electric field at the corner of the triangular prisms is the highest among the circular cylinder dimer and square rod dimmers, which shows that the triangular prism dimer is more suitable for the detection of biomolecules. The triangular prism dimer may also used in plasmonic circuits. 相似文献
998.
In higher plants, cellulose is synthesized by cellulose synthase complexes, which contain multiple isoforms of cellulose synthases (CESAs). Among the total 10 CESA genes in Arabidopsis, recessive mutations at three of them cause the collapse of mature xylem cells in inflorescence stems of Arabidopsis (irx1cesa8, irx3cesa7 and irx5cesa4). These CESA genes are considered secondary cell wall CESAs. The others (the function CESA10 is still unknown) are thought to be specialized for cellulose synthesis in the primary cell wall. A split-ubiquitin membrane yeast two-hybrid system was used to assess interactions among four primary CESAs (CESA1, CESA2, CESA3, CESA6) and three secondary CESAs (CESA4, CESA7, CESA8). Our results showed that primary CESAs could physically interact with secondary CESAs in a limited fashion. Analysis of transgenic lines showed that CESA1 could partially rescue irx1cesa8 null mutants, resulting in complementation of the plant growth defect, collapsed xylem and cellulose content deficiency. These results suggest that mixed primary and secondary CESA complexes are functional using experimental set-ups. 相似文献
999.
Rui Zhang Zhigang Meng Tao Zhou Yong Deng Li Feng Yuan Wang Guoqing Sun Sandui Guo Maozhi Ren 《Plant signaling & behavior》2013,8(11)
FKBP12 encodes a prolyl isomerase and highly conserved in eukaryotic species. In yeasts and animals, FKBP12 can interact with rapamycin and FK506 to form rapamycin-FKBP12 and FK506-FKBP12 complex, respectively. In higher plants, FKBP12 protein lost its function to bind rapamycin and FK506. Early studies showed that yeast and human FKBP12 protein can restore the rapamycin sensitivity in Arabidopsis, but the used concentration is 100–1000 folds higher than that in yeast and animals. High concentration of drugs would increase the cost and cause the potential secondary effects on plant growth and development. Here we further discovered that BP12 plants generated in our previous study are hypersensitive to rapamycin at the concentration as low as that is effective in yeast and animals. It is surprising to observe that WT and BP12 plants are not sensitive to FK506 in normal growth condition. These findings advance the current understanding of rapamycin-TOR signaling in plants. 相似文献
1000.
Minghui Zhou Dongshu Du Keqing Zhao Chunquan Zheng 《Journal of molecular histology》2013,44(3):327-338
Although CD23-dependent transcytosis of IgE and IgE-derived immune complexes across respiratory epithelial cells is likely to play a pivotal role in the initiation and development of airway allergic inflammation, there is currently a lack of physiological support for this phenomena to suggest that the targeting of CD23 could be used as a means of therapeutic intervention. The present study was designed to detect the CD23 expression in the nasal mucosa of allergic rhinitis (AR) murine model by immunohistochemistry and western blotting, and to investigate whether intranasal anti-CD23 treatment could inhibit allergen-induced upper airway inflammation in the AR model. This is the first report to show that CD23 was constitutively expressed in murine nasal epithelial cells, and its expression was significantly up-regulated in the AR murine model. In vivo, the up-regulation of CD23 expression was correlated with increased serum IL-4 levels. Following intranasal anti-CD23 treatment, nasal symptoms were alleviated and histopathologic examination showed a significant decrease in eosinophilic infiltration. Meanwhile, ELISA analysis showed levels of serum leukotriene C4 (LTC4), eosinophil cation protein (ECP), ovalbumin (OVA)-specific IgE and IL-4 also significantly decreased, as were LTC4 and OVA-specific IgE in the nasal lavage fluid. Furthermore, Western blotting analysis showed that ECP expression in the nasal mucosa was down-regulated. Finally, flow cytometric analysis revealed anti-CD23 treatment inhibited Th2 cell responses. These results indicate that intranasal anti-CD23 treatment can reduce allergic responses in a murine model of allergic rhinitis. 相似文献