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81.
探索了无血清培养基对RAW264.7细胞诱导破骨样细胞(osteoclast-like-cell,OCL)分化的影响。结果显示,无血清条件下,M-CSF+RANKL能够诱导RAW264.7细胞分化产生TRAP阳性OCL,F-actin及Hoechst33258染色观察到OCL骨架结构完整、核规则,具有骨吸收活性。这表明在无血清条件下RAW264.7细胞可诱导分化产生OCL,但其存活时间短,此外,M-CSF在其分化过程中具有不可替代的作用。  相似文献   
82.
旨在通过研究NF-κB、Nrf2/HO-1通路来揭示艾纳香油(Blumea balsamifera(L.)DC Oil,BBO)发挥抗炎效果的作用机制。本研究利用LPS诱导的RAW264.7巨噬细胞炎症模型,试验分为空白组、LPS模型组、BBO组(低、中、高剂量)、BBO阴性对照组,每组3个重复,采用Hoechst 33342和PI双染检测BBO对细胞凋亡的影响;采用ELISA和分光光度法检测BBO对LPS诱导巨噬细胞后分泌IL-1β、TNF-α、PGE2、LTB4、NO含量及iNOS活力的影响;采用RT-PCR检测BBO对TNF-αIL-1β的mRNA表达水平的影响;采用Western blotting检测BBO对NF-κB及Nrf2/HO-1信号通路关键蛋白水平的影响。结果显示,BBO在80 μg·mL-1剂量范围内可以扭转LPS导致的巨噬细胞形态变化及细胞凋亡发生;与LPS模型组相比,BBO 60~80 μg·mL-1剂量下可以极显著抑制LPS诱导的细胞炎性因子和炎症介质IL-1β、TNF-α、PGE2、LTB4、NO的分泌及iNOS活力(P<0.01),并极显著抑制LPS导致的细胞IL-1β、TNF-α mRNA表达(P<0.01);同时,BBO 60~80 μg·mL-1剂量下极显著下调LPS导致的COX-2、5-LOX、p-IKKα、p-P65、p-IκB-α、胞质Nrf2蛋白表达(P<0.01),极显著促进HO-1、核Nrf2蛋白表达(P<0.01),并呈现剂量依赖性关系。结果提示,艾纳香油有良好的抑制细胞炎性和抗凋亡效果,其可能通过抑制NF-p-IκBB通路中关键蛋白磷酸化和炎症因子的产生从而促进Nrf2/HO-1通路中主要抗炎基因表达最终发挥抗炎作用。  相似文献   
83.
This study was carried out to investigate the protective effects of chitosan nanoparticles (CNP) against hydrogen peroxide (H2O2)-induced oxidative damage in murine macrophages RAW264.7 cells. After 24 h pre-incubation with CNP (25–200 μg/mL) and chitosan (CS) (50–200 μg/mL, as controls), the viability loss in RAW264.7 cells induced by H2O2 (500 μM) for 12 h was markedly restored in a concentration-dependent manner as measured by MTT assay (P < 0.05) and decreased in cellular LDH release (P < 0.05). Moreover, CNP also exerted preventive effects on suppressing the production of lipid peroxidation such as malondialdehyde (MDA) (P < 0.05), restoring activities of endogenous antioxidant including superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) (P < 0.05), along with increasing total antioxidant capacity (T-AOC) (P < 0.05). In addition, pre-incubation of CNP with RAW264.7 cells for 24 h resulted in the increase of the gene expression level of endogenous antioxidant enzymes, such as MnSOD and GSH-Px (P < 0.05). At the same concentration, CNP significantly decreased LDH release and MDA (P < 0.05) as well as increased MnSOD, GSH-Px, and T-AOC activities (P < 0.05) as compared to CS. Taken together, our findings suggest that CNP can more effectively protect RAW264.7 cells against oxidative stress by H2O2 as compared to CS, which might be used as a potential natural compound-based antioxidant in the functional food and pharmaceutical industries.  相似文献   
84.
The effects of combinations of plant‐derived molluscicides with piperonyl butoxide (PB) or ENT 8184 (MGK‐264) were studied on different enzyme activities and biogenic amine levels in the nervous tissue of Limnaea acuminata. 24‐h in vivo exposure of the nervous tissue of L acuminata to 40% and 80% of the 24‐h LC50 of the plant‐derived molluscicides Azadirachta indica oil, Allium sativum powder and oleoresin of Zingiber officinale rhizome and their active molluscicidal components azadirachtin, allicin and [6]‐gingerol, alone or in combination (1 + 5) with PB or ENT 8184, caused a significant reduction in the activity of acetylcholinesterase, lactic dehydrogenase, acid and alkaline phosphatases and sodium‐potassium ATPase. There was a significant increase in the activity of succinic dehydrogenase. In vivo exposure for 24 h to sub‐lethal concentrations of azadirachtin, allicin and [6]‐gingerol, singly and with PB or ENT 8184, significantly altered the dopamine and 5‐hydroxytryptamine levels in the nervous tissue of L acuminata. It is concluded that these active moieties singly or with PB or ENT 8184 adversely affect all known neurotransmission mechanisms in the snail, either separately or through a complex interaction between the different neurotransmitters. © 2000 Society of Chemical Industry  相似文献   
85.
Inflammation is a double-edged sword, as it can have both protective effects and harmful consequences, which, combined with oxidative stress (OS), can lead to the development of deathly chronic inflammatory conditions. Over the years, research has evidenced the potential of marine sponges as a source of effective anti-inflammatory therapeutic agents. Within this framework, the purpose of this study was to evaluate the antioxidant and the anti-inflammatory potential of the marine sponge Cliona celata. For this purpose, their organic extracts (C1–C5) and fractions were evaluated concerning their radical scavenging activity through 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and anti-inflammatory activity through a (lipopolysaccharides (LPS)-induced inflammation on RAW 264.7 cells) model. Compounds present in the two most active fractions (F5 and F13) of C4 were tentatively identified by gas chromatography coupled to mass spectrometry (GC-MS). Even though samples displayed low antioxidant activity, they presented a high anti-inflammatory capacity in the studied cellular inflammatory model when compared to the anti-inflammatory standard, dexamethasone. GC-MS analysis led to the identification of n-hexadecanoic acid, cis-9-hexadecenal, and 13-octadecenal in fraction F5, while two major compounds, octadecanoic acid and cholesterol, were identified in fraction F13. The developed studies demonstrated the high anti-inflammatory activity of the marine sponge C. celata extracts and fractions, highlighting its potential for further therapeutic applications.  相似文献   
86.
RAW264.7细胞为实验模型,探讨文蛤寡肽(MMO)在体外的免疫调节作用。实验设立空白对照组、阳性药物组(脂多糖,LPS)及低、中、高浓度MMO组,采用MTT比色法检测细胞活性,流式细胞仪检测细胞周期变化,H.E染色观察细胞形态变化,中性红吞噬实验检测细胞吞噬能力,免疫荧光标记法观察诱导型一氧化氮合酶(iNOS)的表达情况,硝酸根还原酶法和酶联免疫吸附法(ELISA)检测细胞培养上清液中一氧化氮、白介素-6(IL-6)和白介素-1β(IL-1β)的含量。结果显示,MMO能促进RAW264.7细胞的增殖和分化。当MMO浓度为250μg/mL时,增强细胞吞噬能力、增加细胞周期中G1/G0期和G2/M期细胞、诱导iNOS刺激NO释放、促进IL-6和IL-1β分泌效果最为显著,表现出与LPS对RAW264.7细胞相似的激活作用。研究表明,MMO具有促使RAW264.7细胞活化,增强非特异性免疫的潜力。  相似文献   
87.
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   
88.
为探究Toll样受体(TLRs)介导的信号通路在马链球菌马亚种(S.equi)感染小鼠巨噬细胞RAW264.7中的作用,收集S.equi感染后不同时间点的RAW264.7细胞,提取总RNA并反转录成cDNA,利用实时荧光定量PCR技术检测细胞Toll样受体1、2、6(TLR1、TLR2、TLR6)、接头蛋白骨髓分化蛋白88(MyD88)及细胞因子IL-1、IL-6、IL-10、IL-12、TNF-αmRNA的表达情况。结果显示,S.equi感染RAW264.7细胞后6h时,TLR1、TLR2、TLR6与MyD88mRNA水平均较对照组没有显著差异(P>0.05);感染后12h时,TLR1、TLR2和TLR6mRNA表达量未出现明显上升(P>0.05),而MyD88mRNA水平极显著升高(P<0.01);感染后24h时,TLR1、TLR2和TLR6mRNA表达水平出现极显著升高(P<0.01),MyD88mRNA表达没有显著变化(P>0.05),且IL-10和IL-12mRNA水平与对照组相比极显著升高(P<0.01),IL-1、IL-6和TNF-αmRNA水平均极显著下降(P<0.01)。结果表明,TLRs介导的信号通路参与S.equi感染RAW264.7细胞的免疫应答反应。  相似文献   
89.
【目的】通过测定先天性免疫效应因子分泌水平的变化,研究鼠李糖乳杆菌(Lactobacillus rhamnosus)体外对巨噬细胞先天性免疫应答调节的影响。【方法】将培养好的鼠巨噬细胞系RAW264.7细胞分为4组,分别用PBS(CT组,对照组)、Escherichia coli K88(EC组)和Lactobacillus rhamnosus(LR组)处理12 h,以及先用Lactobacillus rhamnosus预处理1 h,再用Escherichia coli K88处理12 h(LR-EC组)。试验结束时,收集各组的细胞培养液,用ELISA检测TNF-α、IFN-γ、IL-1β、IL-6、IL-12、IL-8、IL-10,以及PGE2和 的含量。【结果】结果表明,CT组(对照组)可产生TNF-α、IFN-γ、IL-8和IL-10,几乎不产生IL-1β、IL-6和IL-12。与对照组相比,EC组TNF-α、IFN-γ、IL-8、IL-10及PGE2和 含量均极显著提高(P<0.01),且可大量产生IL-1β、IL-6和IL-12;LR组TNF-α、IFN-γ、IL-10及PGE2和 也极显著提高(P<0.01),IL-8显著增加(P<0.05),同样不产生IL-1β和IL-6,但可产生微量的IL-12(P<0.01);LR-EC组所有的促炎细胞因子(TNF-α、IFN-γ、IL-1β、IL-6、IL-12)、趋化因子IL-8和PGE2均极显著高于EC组(P<0.01),但IL-10和 含量都显著低于EC组(P<0.01)。【结论】在体外试验条件下,鼠李糖乳杆菌作为益生菌对生理状态下巨噬细胞先天性免疫应答的刺激作用远低于病原菌,不会产生炎症反应,但可极大增强受感染巨噬细胞的促炎免疫应答水平,且可能具有避免过度炎症反应的作用。  相似文献   
90.
The effect of single, binary, and tertiary combination of few plant derived molluscicides alone or in combination with synergist on different enzymes (acetylcholinesterase—AChE, lactic dehydrogenase—LDH, and acid/alkaline phosphatase—ACP/ALP in the nervous tissue of the freshwater snail Lymnaea acuminata were studied. Sublethal in vivo 24 h exposure to 40 and 80% of LC50 of Azadirachta indica oil (AI), oleoresin of Zingiber officinale (OL), Cedrus deodara oil (CD), Allium sativum (AS), and Polianthes tuberosa (PT) bulb powder singly, their binary combination of AI + OL, AS + CD, AS + PT, CD + OL, CD + PT, OL + PT, and tertiary combination of these binary combinations with the synergist piperonyl butoxide (PB) or MGK-264 significantly altered the activity of these enzymes. Tertiary combination with PB or MGK was very effective. Combination of CD + PT + MGK was more effective against AChE whereas, the combination of CD + OL + PB, CD + AS + PB, and CD + PT + PB were more effective against LDH, ACP, and ALP, respectively.  相似文献   
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