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排序方式: 共有93条查询结果,搜索用时 140 毫秒
51.
Thilina U. Jayawardena K. K. Asanka Sanjeewa Hyo-Geun Lee D. P. Nagahawatta Hye-Won Yang Min-Cheol Kang You-Jin Jeon 《Marine drugs》2020,18(12)
Fucosterol is a phytosterol that is abundant in marine brown algae and is a renowned secondary metabolite. However, its ability to protect macrophages against particulate matter (PM) has not been clarified with regard to inflammation; thus, this study aimed to illustrate the above. Padina boryana, a brown algae that is widespread in Indo–Pacific waters, was applied in the isolation of fucosterol. Isolation was conducted using silica open columns, while identification was assisted with gas chromatography-mass spectroscopy (GC-MS) and NMR. Elevated levels of PM led the research objectives toward the implementation of it as a stimulant. Both inflammation and oxidative stress were caused due the fact of its effect. RAW 264.7 macrophages were used as a model system to evaluate the process. It was apparent that the increased NO production levels, due to the PM, were mediated through the inflammatory mediators, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and pro-inflammatory cytokines (i.e., interleukin-6 (IL-6), interleukin-1 (IL-1β) and tumor necrosis factor-α (TNF-α), including prostaglandin E2 (PGE2)). Further, investigations provided solid evidence regarding the involvement of NF-κB and mitogen-activated protein kinases (MAPKs) in the process. Oxidative stress/inflammation which are inseparable components of the cellular homeostasis were intersected through the Nrf2/HO-1 pathway. Conclusively, fucosterol is a potent protector against PM-induced inflammation in macrophages and hence be utilized as natural product secondary metabolite in a sustainable manner. 相似文献
52.
比较了常见编码标准,指出H.264更符合我国农业视频传输的要求,分析了H.264编码器和解码器的核心技术,总结了H.264的应用优势以及已经取得的成果。 相似文献
53.
通过猪链球菌2型分解代谢控制蛋白A(catabolite control protein A,ccpA)原核表达蛋白对巨噬细胞RAW264.7进行刺激,结果发现,猪链球菌2型ccpA蛋白可以调节巨噬细胞NO产生,另外该蛋白质可通过对iNOS、NF-κB、p38 和 ERK 1/2 MAPK等的调节,从而影响巨噬细胞RAW264.7对细胞因子IL-6、TNF-α和IFN-γ的分泌。该研究为类似蛋白质对免疫细胞NF-κB/MAPK等通路调节影响及细胞因子产生条件探索建立了基础。 相似文献
54.
试验旨在研究结核分枝杆菌Rv2626c蛋白对小鼠巨噬细胞RAW264.7细胞凋亡的影响。根据GenBank数据库中结核分枝杆菌Rv2626c基因序列设计引物,并以结核分枝杆菌国际标准株H37Rv cDNA为模板,PCR扩增Rv2626c基因并克隆至慢病毒表达载体pLEX-EGFP中,包装慢病毒并感染RAW264.7细胞,使用Western blotting和流式细胞仪技术检测Rv2626c蛋白表达水平和RAW264.7细胞凋亡率变化。结果显示,成功构建慢病毒表达载体pLEX-EGFP-Rv2626c;成功包装慢病毒并感染RAW264.7细胞;Rv2626c蛋白在RAW264.7细胞中高水平表达显著促进了细胞凋亡。本试验结果表明,在RAW264.7细胞中过表达结核分枝杆菌Rv2626c蛋白能显著性增加其凋亡水平。 相似文献
55.
Xiaodan Chen Liying Ni Xiaoting Fu Lei Wang Delin Duan Luqiang Huang Jiachao Xu Xin Gao 《Marine drugs》2021,19(8)
Seaweed of Saccharina japonica is the most abundantly cultured brown seaweed in the world, and has been consumed in the food industry due to its nutrition and the unique properties of its polysaccharides. In this study, fucoidan (LJNF3), purified from S. japonica, was found to be a novel sulfated galactofucan, with the monosaccharide of only fucose and galactose in a ratio of 79.22:20.78, and with an 11.36% content of sulfate groups. NMR spectroscopy showed that LJNF3 consists of (1→3)-α-l-fucopyranosyl-4-SO3 residues and (1→6)-β-d-galactopyranose units. The molecular mechanism of the anti-inflammatory effect in RAW264.7 demonstrated that LJNF3 reduced the production of nitric oxide (NO), and down-regulated the expression of MAPK (including p38, ENK and JNK) and NF-κB (including p65 and IKKα/IKKβ) signaling pathways. In a zebrafish experiment assay, LJNF3 showed a significantly protective effect, by reducing the cell death rate, inhibiting NO to 59.43%, and decreasing about 40% of reactive oxygen species. This study indicated that LJNF3, which only consisted of fucose and galactose, had the potential to be developed in the biomedical, food and cosmetic industries. 相似文献
56.
[目的]探讨山豆根多糖(SSP)对猪繁殖与呼吸综合征病毒(PRRSV)体外感染RAW264.7细胞存活率及分泌炎性因子水平的影响,为研发出治疗猪繁殖与呼吸综合征(PRRS)的新型兽药提供参考依据.[方法]以50、100、200和400 μg/mL SSP作用于PRRSV体外感染8h的RAW264.7细胞,通过MTT法评价SSP对PRRSV感染RAW264.7细胞存活率,ELISA检测SSP对PRRSV体外感染RAW264.7细胞培养上清液中的炎性因子TNF-α、IL-1β、IL-6、IL-8、IL-10和MCP-1.[结果]PRRSV感染RAW264.7细胞8h极显著降低了细胞存活率(P<0.01,下同),而200~400 μg/mL SSP能极显著升高PRRSV感染RAW264.7细胞存活率.PRRSV感染RAW264.7细胞8h可极显著升高细胞分泌TNF-α、IL-1β、IL-6、IL-8、IL-10和MCP-1水平,而SSP能有效降低PRRSV感染RAW264.7细胞分泌上述炎性因子水平,其中以200~400μg/mL SSP的抑制效果最佳.[结论]SSP通过提高炎症细胞存活率及抑制其分泌炎性因子水平,从而有效干预PRRSV感染免疫细胞的炎性反应. 相似文献
57.
JI Wen-jie HU Dao-chuan CHEN Xue-fen MA Yong-qiang LU Rui-yi ZHOU Xin WEI LU-qing 《园艺学报》2012,28(12):2261-2265
AIM: To establish stable knockdown of mineralocorticoid receptor (MR) expression through short hairpin RNA (shRNA)-mediated silencing in murine RAW 264.7 macrophages. METHODS: Stable MR silencing in RAW 264.7 cells was achieved by recombinant shRNA plasmid targeting murine MR gene via liposome-mediated transfection, followed by G418 selection. The efficacies of plasmid transfection and MR silencing in G418-resistant cells were verified by immunofluorescent microcopy and real-time PCR, respectively. Proliferative activity of MR-silencing cell line was analyzed by CCK-8 assay. Cell cycle and apoptosis were evaluated by flow cytometry. RESULTS: MR gene expression was down-regulated by 70% compared with the negative control (NC) plasmid transfection. In addition, MR-silencing cells exhibited lower proliferative activity compared with NC and wide type RAW 264.7 cells (P<0.05), along with reduced proliferation index of 31.0%±1.3% (P<0.05), compared with the wide type cells (37.2%±0.5%) and the NC cells (37.5%±1.6%). In resting state, the apoptotic rate in wide type, NC and MR-silencing cells were 2.18%±0.36%, 6.65%±0.81% and 7.70%±1.34%, respectively, and no statistical difference was observed between NC and MR-silencing cells (P>0.05). CONCLUSION: MR gene silencing inhibits the proliferation of RAW 264.7 macrophages, but has no obvious effect on the apoptosis of the resting state cells. 相似文献
58.
为研究小刺猴头菌[Hericium caput-medusae(Bull.:Fr.)Pers]发酵浸膏多糖的抗氧化活性。以工厂化小刺猴头菌发酵浸膏为原料,采用透析法分级,DEAE sepharose fast flow柱层析纯化,分别获得粗多糖组分HFCP1和中性多糖HFCP1-1;通过PMP柱前衍生-高效液相色谱法和红外光谱法对单糖组成和结构进行分析,单糖组成均以葡萄糖和半乳糖为主。化学法检测多糖抗氧化活性,结果显示:HFCP1和HFCP1-1清除羟基自由基、超氧阴离子自由基、2,2′-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(2,2′-azinobis-3-ethylbenzthiazoline-6-sulphonate,ABTS+)和1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)的IC50值分别为7.66和6.77mg/mL、6.16和5.30mg/mL、0.63和0.85mg/mL、0.39和2.62mg/mL。以RAW264.7细胞建立H2O2诱导损伤模型,细胞抗氧化结果表明:HFCP1和HFCP1-1处理组与模型组相比均显著增强细胞活力(P0.05),浓度为100和200mg/L时MDA含量与模型组相比均显著下降(P0.05);HFCP1浓度为100和200mg/L时与模型组相比显著增加SOD和GSH-Px的活性(P0.05);HFCP1-1浓度为200mg/L时与模型组相比显著增加SOD活性(P0.05);也能增加GSH-Px的活性,但未达到显著水平(P0.05)。 相似文献
59.
Xing-Wei Xiang Rui Wang Li-Wen Yao Yu-Fang Zhou Pei-Long Sun Bin Zheng Yu-Feng Chen 《Marine drugs》2021,19(8)
Considerable literature has been published on polysaccharides, which play a critical role in regulating the pathogenesis of inflammation and immunity. In this essay, the anti-inflammatory effect of Mytilus coruscus polysaccharide (MP) on lipopolysaccharide-stimulated RAW264.7 cells and a dextran sulfate sodium (DSS)-induced ulcerative colitis model in mice was investigated. The results showed that MP effectively promoted the proliferation of RAW264.7 cells, ameliorated the excessive production of inflammatory cytokines (TNF-α, IL-6, and IL-10), and inhibited the activation of the NF-κB signaling pathway. For DSS-induced colitis in mice, MP can improve the clinical symptoms of colitis, inhibit the weight loss of mice, reduce the disease activity index, and have a positive effect on the shortening of the colon caused by DSS, meliorating intestinal barrier integrity and lowering inflammatory cytokines in serum. Moreover, MP makes a notable contribution to the richness and diversity of the intestinal microbial community, and also regulates the structural composition of the intestinal flora. Specifically, mice treated with MP showed a repaired Firmicutes/Bacteroidetes ratio and an increased abundance of some probiotics like Anaerotruncus, Lactobacillus, Desulfovibrio, Alistipe, Odoribacter, and Enterorhabdus in colon. These data suggest that the MP could be a promising dietary candidate for enhancing immunity and protecting against ulcerative colitis. 相似文献
60.
The effects of sub-lethal treatments (20 and 60% of 24-h LC(50)) with plant-derived molluscicides Annona squamosa, acetogenins, Argemone mexicana seed and protopine, in combination (1 + 5) with MGK-264 (ENT 8184) or piperonyl butoxide on the reproduction of Lymnaea acuminata has been studied. The plant-derived molluscicides and their active molluscicidal components, protopine and acetogenins, in combination with ENT 8184 or piperonyl butoxide caused a significant reduction in the fecundity, hatchability and survival of young snails. Combination of A squamosa seed powder with piperonyl butoxide was very effective as it caused a complete arrest of snail fecundity within 24 h of treatment. Removal of the snails to fresh water after the 96-h treatments caused a significant recovery in the fecundity of L acuminata. 相似文献