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21.
目的研究肺炎衣原体(Cpn)的培养及对RAW264.7细胞(人喉癌细胞)的感染。方法应用低速离心法在Hep-2细胞(小鼠巨噬细胞株)内培养Cpn,光镜及电镜下观察Cpn在Hep-2细胞内增殖情况。提取的Cpn感染RAW264.7细胞,Giemsa染色检测RAW264.7内Cpn感染情况。结果Cpn能在Hep-2细胞内增殖,提取的Cpn可感染RAW264.7细胞,并在RAW264.7细胞内形成包涵体。结论在Hep-2细胞内成功培养了Cpn;Cpn能感染RAW264.7细胞。  相似文献   
22.
目的考察不同PEG含量对mPEG-PLGA-mPEG(PELGE)纳米粒血浆蛋白吸附和巨噬细胞吞噬的影响。方法利用SDS-PAGE电泳技术,分析不同纳米粒的血浆蛋白吸附;以小鼠巨噬细胞RAW 264.7为模型,采用化学发光法分析不同纳米粒的吞噬情况。结果与结论PEG含量为5%~10%时,纳米粒吸附最少的血浆蛋白,而且被巨噬细胞吞噬也最少。由此,可设计出适合于静脉注射的、可生物降解的、长循环的药物载体。  相似文献   
23.
Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) has played a crucial role in various pathophysiological processes including inflammation and carcinogenesis. Therefore, the inhibitors of NO synthesis or iNOS gene expression have been considered as potential anti-inflammatory and cancer chemopreventive agents. In our continuous search for iNOS inhibitors from natural products we have evaluated indigenous Korean plant extracts using an assay for inhibition of nitric oxide formation on lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells. As a result, the methanolic stem extract of Actinodaphne lancifolia showed an inhibitory activity of NO production in a dose-dependent manner (IC50 = 2.5 microg/ml). Additional study demonstrated that the extract of Actinodaphne lancifolia significantly suppressed the iNOS protein and gene expression in a dose-dependent manner. These results suggest that Actinodaphne lancifolia could be a potential candidate for developing an iNOS inhibitor from natural products. Further elucidation of active principles for development of new cancer chemopreventive and/or anti-inflammatory agents could be warranted.  相似文献   
24.
《Toxicology in vitro》2010,24(4):1119-1125
Gasoline engine exhaust has been considered as a major source of air pollution in China. Due to lower cyto- and geno-toxicity effects of methanol engine exhaust, methanol is regarded as a potential substitute for gasoline. We have previously compared cyto- and geno-toxicities of gasoline engine exhaust with that of methanol engine exhaust in A549 cells (Zhang et al., 2007).To characterize the immunotoxic effects for gasoline and methanol engine exhausts in immune cell, in this study, we further compared effects of gasoline and methanol engine exhausts on immune function in RAW264.7 cell and rabbit alveolar macrophages. Results showed that both gasoline and methanol engine exhaust could evidently inhibit RAW264.7 cell proliferation, promote RAW264.7 cell apoptosis, decrease E-rosette formation rate and inhibit anti-tumor effects of alveolar macrophages, at the same time, these effects of gasoline engine exhaust were far stronger than those of methanol engine exhaust. In addition, gasoline engine exhaust could significantly inhibit activities of ADCC of alveolar macrophages, but methanol engine exhaust could not. These results suggested that both gasoline and methanol engine exhausts might be immunotoxic atmospheric pollutants, but some effects of gasoline engine exhaust on immunotoxicities may be far stronger than that of methanol engine exhaust.  相似文献   
25.

Aim of the study

To ascertain the effective constituents in Xiexin Decoction for anti-inflammation and the interactions of these constituents at the pharmacodynamic level.

Materials and Methods

Rats were administered oral Xiexin Decoction 1 h before intraperitoneal lipopolysaccharide. Nitric oxide production and Xiexin Decoction constituents in venous serum samples were quantified and the correlation between nitric oxide production and each constituent in serum was calculated. Raw264.7 cells were stimulated with lipopolysaccharide and one or more Xiexin Decoction constituents; cell viability and nitric oxide production was quantified.

Results

Xiexin Decoction significantly decreased nitric oxide production in vivo, which correlated well with rhein, baicalin, emodin and aloe-emodin. All the typical constituents of Xiexin Decoction, with the exception of physcione and chrysophanol, dose-dependently inhibited nitric oxide production in vitro. In an orthogonal designed in vitro study, rhein was the most powerful constituent, followed by baicalin then berberine and no synergy was found among these constituents.

Conclusions

Rhein was the most effective anti-inflammatory constituent in Xiexin Decoction followed by baicalin; no synergy was observed between rhein, baicalin and berberine at the pharmacodynamic level in vitro.  相似文献   
26.
Objective To compare the morphologic change and cytokines expression in RAW264.7 and Ana-1 stimulated by lipopolysaccharide(LPS). Methods RAW264.7 and Ana-1 were cultivated with various concentrations of LPS(0.1 mg/L, 1 mg/L, 10 mg/L, 100 mg/L). MTT was performed to evaluate the proliferation ability of cells. Two kinds of cells were cultivated with 1 mg/L. Then,the concentrations of TNF-α,IL-1β,IL-6,IL-10 in culture medium were detected by ELISA in different times(0 h,4 h,8 h,12 h,24 h). Results The survival rates of RAW264.7 and Ana-1 (162.05±28.14)% and (159.92±20.43)% were significantly higher in 1 mg/L group than those of other groups. When stimulated with 1 mg/L LPS, both RAW264.7 and Ana-1 expressed cytokines in time-dependent manner (increased first and decreased finally). The concentrations of TNF-α and IL-10 in RAW264.7 group were higher than those Ana-1 group in 4 h only. IL-1β and IL-6,however,were in higher concentrations in RAW264.7 group than Ana-1 group all the time. Conclusions When stimulated with 1 mg/L LPS, both RAW264.7 and Ana-1 have higher survival rate. RAW264.7 and Ana-1 have different ability in expressing cytokines after being stimulated by LPS. Therefore,RAW264.7 and Ana-1 have variant response to LPS slightly.  相似文献   
27.
目的 筛选赪桐乙酸乙酯部位及不同洗脱梯度二氯甲烷-甲醇部位对炎症反应的抑制作用最强的流份。 方法 使用MTT法确定壮药赪桐乙酸乙酯部位及不同洗脱梯度二氯甲烷-甲醇部位对RAW264.7细胞安全给药浓度范围,通过ELISA法测定赪桐乙酸乙酯部位及不同洗脱梯度二氯甲烷-甲醇部位对LPS诱导RAW264.7细胞分泌NO、TNF-a、IL-12、IL-6、IL-1β含量,筛选对炎症反应的抑制作用最强的流份。 结果 赪桐乙酸乙酯部位及流份在0.06~2.0 mg/ml浓度范围内,赪桐乙酸乙酯部位及流份对细胞活力的抑制作用逐渐增强,浓度在0.5 mg/ml以上具有明显的细胞毒性,在0.5 mg/ml以下对细胞活力具有增强作用。二氯甲烷-甲醇洗脱部位高剂量能抑制炎症因子IL-12、IL-6、TNF-a、IL-1β释放,对NO的分泌没有抑制作用。 结论 赪桐乙酸乙酯部位及不同洗脱梯度的二氯甲烷-甲醇部位抗炎机制是通过抑制NO、TNF-a、IL-12、IL-6、IL-1β炎症因子的分泌,二氯甲烷-甲醇(50:1)洗脱部位和二氯甲烷-甲醇(30:1)洗脱部位的抗炎能力较强。  相似文献   
28.
王松  王微  罗猛  赵修华  祖元刚  赵艳丽 《药学进展》2012,36(10):465-470
目的:研究复方甘草酸苷片剂和注射剂对脂多糖诱导小鼠巨噬细胞RAW 264.7分泌炎症因子的调节作用。方法:采用脂多糖诱导的小鼠巨噬细胞RWA264.7,建立体外炎症模型。取复方甘草酸苷片剂和注射剂,制备供试药液。分别通过,MTT、Griess和双抗体夹心ABC-ELISA等实验,测定在不同浓度的供试药液作用下RAW264.7细胞活力以及经脂多糖诱导后的RAW264.7细胞的一氧化氮、肿瘤坏死因子TNF-α及白介素IL-1β、-6和-10等炎症因子分泌量的变化。结果:复方甘草酸苷的2种制剂药液在0~300μmol.L-1浓度范围内对RAW264.7细胞活力无影响。复方甘草酸苷注射剂药液在75、150和300μmol.L-1浓度下对经脂多糖处理的RAW264.7细胞的一氧化氮分泌抑制率分别为13.8%、40.4%和53.8%,并致细胞的TNF-α分泌量降低29.8%、41.5%和52.1%,IL-1β分泌量降低39.5%、55.6%和69.6%,IL-6分泌量降低18.3%、29.5%和39.1%,但IL-10分泌量却提高了8.2%、23.8%和30.8%;而复方甘草酸苷片药液在相同浓度下对同样细胞的一氧化氮分泌抑制率分别为9.8%、27.1%和37.8%,致细胞的TNF-α分泌量降低16.6%、37.0%和48.4%,IL-1β分泌量降低28.1%、47.9%和57.9%,IL-6分泌量降低13.5%、19.9%和28.2%,IL-10分泌量提高了3.9%、14.8%和23.4%。复方甘草酸苷的2种制剂对细胞分泌炎症因子的调节作用与阳性对照药地塞米松相似,其中注射剂的作用强于片剂。结论:复方甘草酸苷可剂量依赖性地显著抑制脂多糖诱导小鼠RAW 264.7细胞产生促炎因子一氧化氮、TNF-α及IL-1β和-6并促进抗炎因子IL-10的表达,这可能为其抗炎作用机制。  相似文献   
29.
X射线照射对RAW264·7细胞TNF-α和NF-κB表达的影响   总被引:1,自引:0,他引:1  
目的探讨X射线照射诱发小鼠巨噬细胞分泌TNF-α和NF-κB的规律。方法以8Gy X射线单次照射小鼠巨噬细胞系RAW264.7细胞,并于照后不同时间收集细胞培养上清液,采用ELISA法检测RAW264.7细胞TNF-α分泌水平;以8Gy X射线单次照射小鼠巨噬细胞系RAW264.7细胞,并于照后不同时间收集细胞并进行裂解,采用Western blot实验检测NF-кB(p65)的表达。结果 X射线照射能使小鼠巨噬细胞分泌TNF-α增加,在照射后34h达到一次分泌峰值;细胞核中NF-κB(p65)分布增多,并且随着时间的延长其核移位明显增多,照射后4h达到一次最高值。结论 X射线照射能诱发小鼠巨噬细胞TNF-α和NF-κB表达增强。  相似文献   
30.
Osteoclasts are the unique cell type capable of resorbing bone. The discovery of the TNF-ligand family member, RANKL, has allowed more reliable study of these important cells. The mouse monocytic cell line, RAW 264.7, has been shown to readily differentiate into osteoclasts upon exposure to recombinant RANKL. Unlike primary osteoclast precursors, there is no requirement for the addition of macrophage colony stimulating factor (M-CSF). However, to date, their differentiation has always been studied in the context of added foetal calf serum (FCS). FCS is a complex and largely undefined mixture of growth factors and matrix proteins, and varies between batches. For this reason, osteoclastogenesis would ideally be studied in the context of a defined, serum-free medium. RAW 264.7 cells were cultured in serum-replete α-MEM or serum-deprived medium (SDM) shown previously to support the growth of human osteoclasts in a co-culture with normal osteoblasts. In SDM, in the presence of recombinant RANKL, RAW 264.7 cells readily differentiated into tartrate resistant acid phosphatase (TRAP) positive multinucleated osteoclast-like cells, a process that was enhanced with the addition of 1α,25-dihydroxyvitamin D3 (1,25D). While the osteoclasts grown in SDM were smaller in size compared with those derived in serum-replete media, their resorptive capacity was significantly increased as indicated by a twofold increase in average resorption pit size. In conclusion, we describe a defined model for studying osteoclast differentiation and activity in the absence of serum, which will be ideal for studying the role of agonistic and antagonistic molecules in this process.  相似文献   
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