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991.
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为丰富海洋真菌的化学多样性,发现海洋真菌活性代谢产物,对海洋沉积物来源真菌Arthriniumsp.UJNMF0008的化学成分及其生物活性进行研究,采用硅胶柱色谱、凝胶柱色谱、反向柱色谱和高效液相色谱等方法从海洋沉积物来源真菌Arthriniumsp.UJNMF0008的发酵提取物中分离到5个化合物,通过核磁共振、质谱等方法,结合文献对照,鉴定了化合物的结构分别为arthoneF(1)、arthoneG(2)、sydoxanthoneC(3)、(3R,4R)-cis-4-hydroxymellein(4)和2-(2′S-hydroxypropyl)-5-methyl-7-hydroxychromone(5),其中化合物1和2是新化合物,化合物3首次从该属真菌中分离到。活性测试显示,化合物1~5在50μmoL/L的测试浓度下均没有表现出明显的抗氧自由基活性、抗菌活性以及NO释放抑制活性。 相似文献
994.
The grand jackknife clam Solen grandis is a commercially important mollusk species, but has been suffering from severe population decline due to over-exploitation and habitat destruction in China. To promote a conservation program for this species, it is necessary to evaluate its genetic diversity and population genetics. In this study, 10 novel polymorphic microsatellite makers were developed and characterized from the S. grandis through high throughput sequencing. The number of alleles at each locus ranged from 10 to 34 with an average of 20.8 alleles per locus. The observed and expected heterozygosities varied from 0.433 to 1.000 and from 0.696 to 0.976, with an average of 0.793 and 0.884, respectively. The polymorphism information content (PIC) value ranged from 0.633 (Sg43838) to 0.958 (Sg3754), with an average of 0.858. The cross-species amplification transferability of 10 loci to three closely related species ranged from 4.17 to 62.5%. These microsatellite loci will be useful for further investigation of population structure and conversation genetics of this species. 相似文献
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Yueming Zhang Wenrui Zhang Lina Tao Jinghui Zhai Huan Gao Yanqing Song Xiaoyu Qu 《Journal of biochemical and molecular toxicology》2019,33(9)
Isoniazid (INH) is one of the most commonly used antituberculosis drugs, but its clinical applications have been limited by severe hepatic toxicity. Quercetin (Que), a natural flavonoid, has been proved to have many medicinal properties. This study aimed to clarify the possible protective effects of Que against INH‐induced hepatotoxicity using HepG2 cells. Our results indicated that Que significantly increased cell viability, superoxide dismutase, and GSH levels, while decreased alanine aminotransferase/aspartate aminotransferase levels. Besides, Que significantly abrogated INH‐induced cell apoptosis by upregulating the expression levels of Bcl‐2 and decreasing the levels of Bax, cleaved caspase‐3, and cleaved caspase‐9. Furthermore, Que obviously reversed the inhibition of INH on Sirtuin 1 (SIRT1) expression and extracellular signal‐regulated kinase (ERK) phosphorylation. Next, the SIRT1 inhibitor EX527 blocked the enhancement of Que upon ERK phosphorylation. Notably, EX527 partially abolished the beneficial effects of Que. In brief, our results provided the first evidence that Que protected against INH‐induced HepG2 cells by regulating the SIRT1/ERK pathway. 相似文献
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Dongmei Mao Hong Li Lei Zhang Jian Xu Chunyan Yu Qi Zhang 《Journal of biochemical and molecular toxicology》2019,33(12)
Ankylosing spondylitis (AS) is a high disability and greatly destructive disease. In this study, we preliminarily studied the function and mechanism of bilobalide (BIL) on interleukin (IL)‐17‐induced inflammatory injury in ATDC5 cells. CCK‐8 and migration assays were used to detect the functions of IL‐7, BIL, and microRNA (miR)‐125a on cell viability and migration. The miR‐125a level was changed by transfection, and tested by real‐time quantitative polymerase chain reaction. Additionally, Western blot tested the levels of inflammatory factors (IL‐6 and tumor necrosis factor‐α), matrix metalloproteinases (MMPs), and pathway‐related proteins. Moreover, the enzyme‐linked immunosorbent assay also was used to detect inflammatory factor levels. IL‐7 was used to construct an inflammatory injury model in ATDC5 cells. Based on this, BIL inhibited IL‐17‐induced cell viability, migration, and expressions of inflammatory factors and MMPs. Furthermore, we found BIL negatively regulated miR‐125a, and the miR‐125a mimic could partly reverse the effects of BIL on IL‐17‐injury. Finally, we showed that BIL inhibited the c‐Jun N‐terminal kinase (JNK) and nuclear factor kappa B (NF‐κB) pathways, and the miR‐125a mimic had the opposite effect. BIL inhibited IL‐17‐induced inflammatory injury in ATDC5 cells by downregulation of miR‐125a via JNK and NF‐κB signaling pathways. 相似文献