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Wenjuan Ding Fangfang Wang Qingwen Li Yaxin Xue Zhitong Dong Danmei Tian Mei Chen Youwei Zhang Kui Hong Jinshan Tang 《化学与生物多样性》2021,18(7):e2100229
Marine derived fungus has gained increasing ground in the discovery of novel lead compounds with potent biological activities including anti-inflammation. Here, we first report the characterization of one new sorbicillinoid ( 1 ) and fourteen known compounds ( 2 – 15 ) from the ethyl acetate (AcOEt) extract of a cultured mangrove derived fungus Penicillium sp. DM815 by UV, IR, HR ESI-Q-TOF MS, and NMR spectra. We then evaluated the anti-inflammatory effects of eleven sorbicillinoids ( 1 – 11 ) using cultured macrophage RAW264.7 cells. The results show that compound 9 , and to a lesser degree compound 5 , significantly inhibited the Gram-negative bacteria lipopolysaccharide (LPS)-induced upregulation of the inducible nitric oxide synthase (iNOS). Consistently, compounds 5 and 9 significantly reduced the level of nitric oxide (NO), the product of iNOS, induced by LPS. We further show that these two compounds dose-dependently inhibited LPS-triggered iNOS expression and NO production, but had no effect on proliferation of RAW264.7 cells in the presence of LPS. In conclusion, our study identifies novel and known sorbicillinoids as potent anti-inflammatory agents, holding the promise of developing novel anti-inflammation treatment in the future. 相似文献
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Shu Xian Yan Zhang Li Wang Fang Yao Jinli Ding Yanqing Wang Xiao Yang Fangfang Dai Tailang Yin Yanxiang Cheng 《Journal of cellular and molecular medicine》2021,25(8):3885-3897
The INO80 complex, a SWI/SNF family chromatin remodeler, has regulatory effects on ESC self-renewal, somatic cell reprogramming and blastocyst development. However, the role of INO80 in regulating trophoblast cells and recurrent miscarriage (RM) remains elusive. To investigate the in vivo effects of Ino80 in embryo development, we disrupted Ino80 in C57 mice, which resulted in embryonic lethality. Silencing of Ino80 led to decreased survival capacity, migration and invasion of trophoblasts. Furthermore, RNA high-throughput sequencing (RNA-seq) revealed that Ino80 silencing closely resembled the gene expression changes in RM tissues. To investigate the mechanisms for these results, RNA-seq combined with high-throughput sequencing (ChIP-seq) was used in trophoblast cells, and it showed that Ino80 physically occupies promoter regions to affect the expression of invasion-associated genes. Last, Western blotting analyses and immunofluorescence staining revealed that the content of INO80 was reduced in RM patients compared to in healthy controls. This study indicates that INO80 has a specific regulatory effect on the viability, migration and invasion of trophoblast cells. Combined with its regulation of the expression of invasion-associated genes, it has been proposed that epigenetic regulation plays an important role in the occurrence of RM, potentially informing RM therapeutic strategies. 相似文献
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粤北南岭大宝山矿流域山水林田湖草修复阻力与优先级分析 总被引:1,自引:0,他引:1
遵循“防源、控流、治汇”理念,以粤北南岭大宝山矿区作为风险源,以所在流域为研究区,分析研究区主要阻力因素,采用最小累积阻力模型建立区域生态阻力面;利用Jenks自然断点法,分析生态修复优先级,提出分区治理重点和对策。研究结果表明:研究区综合阻力系数处于9-32之间,各评价指标的阻力面空间分布格局相似,其阻力值呈现出东南部大,西北部小的空间格局;长期的矿业开采污染了流域生态环境,且距离矿区越近的区域生态修复的优先性越高。将研究区分为4个优先级区,各区修复优先性依次为Ⅰ区 > Ⅱ区 > Ⅲ区 > Ⅳ区。Ⅰ区重点在于治水,提高pH、降低重金属有效态含量和增加地表植被覆盖度。Ⅱ区重点在于河流治理与治土,确保污染减排,增强拦泥库的废水调节。Ⅲ区、Ⅳ区核心在治土,逐步改善土壤条件。研究结果为修复项目在时空尺度上落地和科学治理提供科学依据。 相似文献
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作为生态系统稳定性维持的一个重要因素,火对泥炭地优势植物泥炭藓(Sphagnum)孢子库的影响尚不清楚.以采自长白山区泥炭地的泥炭土和3种泥炭藓的成熟孢子为实验材料,室内模拟火烧,以此设置不同温度水平(20、40、60或100℃,持续0.5、1、2、4或10 min),对泥炭藓孢子进行热激处理,经萌发实验后,研究火烧高温对孢子萌发率的影响.结果显示,火烧期间各层土温随深度而递减,表层泥炭可达300℃的极端高温,而1 cm深温度仅为70℃,体现出泥炭土良好的热缓冲性;40℃的热激可使锈色泥炭藓(S.fuscum)与中位泥炭藓(S.magellanicum)孢子萌发率提高20%与50%;60℃的热激使尖叶泥炭藓(S.capillifolium)孢子的萌发率提高1倍;100℃热激对3种泥炭藓孢子萌发则有强烈的抑制作用.研究表明,泥炭藓孢子耐受高温的能力有限,但土壤中的孢子凭借泥炭的良好热缓冲性,可以躲避火烧高温造成的致命伤害,适度的热激甚至能提高其萌发力,对其在火后的建植及种群的长存可能有重要意义. 相似文献
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