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61.
Ying Yin Bailiang Xu Zhiyong Li Baohua Zhang 《World journal of microbiology & biotechnology》2013,29(3):441-446
(+)-Terrein is a fungal metabolite with multiple biological activities, especially with great value in medicine. However, the mass production of single configuration terrein is still a big challenge. In this study, the effects of acetic acid, sodium acetate, citric acid and sodium citrate on the (+)-terrein production by Aspergillus terreus strain PF26 derived from marine sponge Phakellia fusca were investigated. Sodium citrate was selected for fed-batch cultivation because it showed the best effect on (+)-terrein production among the four regulators tested. As a result, 5.38 g/L (+)-terrein production was achieved by feeding 10 mM sodium citrate on the 3rd day in shake flask, which was 33.8 % higher than the control and represented the highest yield of (+)-terrein. In a 7.5-L stirred bioreactor, 2.58 g/L of (+)-terrein production was achieved by the feeding of 10 mM sodium citrate on the 8th day. The results from this study lay a basis for the high-yield production of (+)-terrein by fermentation. 相似文献
62.
Kang Wang Shuling You Hesheng Hu Xiaolu Li Jie Yin Yugen Shi Lei Qi Pingjiang Li Yuepeng Zhao Suhua Yan 《Journal of cellular and molecular medicine》2022,26(10):2959
Sympathetic activation after myocardial infarction (MI) leads to ventricular arrhythmias (VAs), which can result in sudden cardiac death (SCD). The toll‐like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor‐kappa B (NF‐kB) axis within the hypothalamic paraventricular nucleus (PVN), a cardiac‐neural sympathetic nerve centre, plays an important role in causing VAs. An MI rat model and a PVN‐TLR4 knockdown model were constructed. The levels of protein were detected by Western blotting and immunofluorescence, and localizations were visualized by multiple immunofluorescence staining. Central and peripheral sympathetic activation was visualized by immunohistochemistry for c‐fos protein, renal sympathetic nerve activity (RSNA) measurement, heart rate variability (HRV) analysis and norepinephrine (NE) level detection in serum and myocardial tissue measured by ELISA. The arrhythmia scores were measured by programmed electrical stimulation (PES), and cardiac function was detected by the pressure–volume loop (P‐V loop). The levels of TLR4 and MyD88 and the nuclear translocation of NF‐kB within the PVN were increased after MI, while sympathetic activation and arrhythmia scores were increased and cardiac function was decreased. However, inhibition of TLR4 significantly reversed these conditions. PVN‐mediated sympathetic activation via the TLR4/MyD88/NF‐kB axis ultimately leads to the development of VAs after MI. 相似文献
63.
Long-term use of antibiotics has engendered a large number of resistant pathogens, which pose a serious threat to human health. Here, we investigated the mechanism of fusaricidin antibacterial activity toward Bacillus subtilis and characterized the pathways responsible for drug resistance. We found that σw, an extracytoplasmic function sigma factor, plays an important role in the resistance to fusaricidins during the initial 5 minutes of drug addition. Approximately 18 genes were induced more than 3-fold, of which 66.7% are known to be regulated by σw. Over the following 3 h, fusaricidins induced 194 genes more than three-fold, and most were associated with classes of antibiotic-responsive stimulons. Moreover, the fusaricidin treatment increased the catabolism of fatty and amino acids but strongly repressed glucose decomposition and gluconeogenesis. In summary, our data provide insight into the mechanism of fusaricidin activity, on which we based our suggested strategies for the development of novel antibiotic agents. 相似文献
64.
Jianli Liu Siqi Tian Mingyang Fu Yin He Hui Yu Xiangyu Cao Yiyang Cao Hanyuan Xu 《化学与生物多样性》2020,17(2)
Anthocyanins (AC) from Coreopsis tinctoria possesses strong antioxidant properties, while the effects of AC on cells damage induced by reactive oxygen species (ROS) in diabetes mellitus diseases progression have not been reported. The present study was carried out to evaluate the protective property of AC against cellular oxidative stress with an experimental model, H2O2‐exposed MIN6 cells. AC could reverse the decrease of cell viability induced by H2O2 and efficiently suppressed cellular ROS production and cell apoptosis. In addition, Real‐time PCR and Western blot analyses indicated that AC could protect MIN6 cells against oxidative injury through increasing the translocation of Nrf2 into nuclear, decreasing the phosphorylation level of p38 and up‐regulating the protein expression of antioxidant enzyme (SOD1, SOD2 and CAT). Thus, this study provides evidence to support the beneficial effect of AC in inhibiting MIN6 cells from H2O2‐induced oxidative injury. 相似文献
65.
66.
Zhongkai Hao Qi Chen Wenrui Dai Yinjuan Ren Yin Zhou Jinlin Yang Sijie Xie Yanbin Shen Jihong Wu Wei Chen Guo Qin Xu 《Liver Transplantation》2020,10(10)
Developing a titanium dioxide (TiO2)‐based anode with superior high‐rate capability and long‐term cycling stability is important for efficient energy storage. Herein, a simple one‐step approach for fabricating blue TiO2 nanoparticles with oxygen vacancies is reported. Oxygen vacancies can enlarge lattice spaces, lower charge transfer resistance, and provide more active sites in TiO2 lattices. As a result, this blue TiO2 electrode exhibits a highly reversible capacity of 50 mAh g?1 at 100 C (16 800 mA g?1) even after 10 000 cycles, which is attributable to the combination of surface capacitive process and remarkable diffusion‐controlled insertion revealed by the kinetic analysis. The strategy of employing oxygen‐deficient nanoparticles may be extended to the design of other robust semiconductor materials as electrodes for energy storage. 相似文献
67.
68.
植物的无机元素分布特征对植物生理过程具有重要的指标作用, 可揭示营养物质分布、代谢途径及毒理耐受性等多种生命过程。用微区XRF技术测试样品中无机元素的分布, 具有原位无损、可进行较大面积样品连续成像分析以及前处理过程简单等诸多优势。将微区XRF技术应用于植物样品不同器官的无机元素分布检测, 旨在探讨该技术在植物样品测试中的仪器参数选择、样品前处理方法和数据后处理手段等对测试结果的影响。为得到可靠的实验结果, 对不同含水量的器官进行不同的前处理, 并比较不同驻留时间、测试腔体真空与否等仪器条件对测试结果的影响, 同时对数据处理方法进行探索, 包括对获得的数据进行图像叠加及对不同元素浓度比例进行半定量分析。研究结果表明, 微区XRF技术测试植物样品中无机元素分布具有一定的技术优势。 相似文献
69.
Shen He Wu Shuyu Chen Xi Xu Bai Ma Dezun Zhao Yannan Zhuang Yan Chen Bing Hou Xianglin Li Jiayin Cao Yudong Fu Xianyong Tan Jun Yin Wen Li Juan Meng Li Shi Ya Xiao Zhifeng Jiang Xingjun Dai Jianwu 《中国科学:生命科学英文版》2020,63(12):1879-1886
Science China Life Sciences - Spinal cord injury (SCI), especially complete transected SCI, leads to loss of cells and extracellular matrix and functional impairments. In a previous study, we... 相似文献
70.
Lu Ligong Zhang Hui Zhan Meixiao Jiang Jun Yin Hua Dauphars Danielle J. Li Shi-You Li Yong He You-Wen 《中国科学:生命科学英文版》2020,63(12):1833-1849
Science China Life Sciences - The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected millions of people and caused tremendous morbidity and mortality worldwide.... 相似文献