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Schistosoma mansoni is a blood fluke parasite responsible for schistosomiasis. The best long‐term strategy to control schistosomiasis is through immunization combined with drug treatment. In this study, we cloned, expressed and purified SmTSP‐2 fused to the N‐ and C‐terminal halves of Sm29 and tested these chimeras as vaccine candidates using an adjuvant approved to be used in humans. The results demonstrated that vaccination with SmTSP‐2 fused to N‐ or C‐terminus of Sm29‐induced reduction in worm burden and liver pathology when compared to control animals. Additionally, we detected high levels of mouse‐specific IgG, IgG1 and IgG2a against both chimeras and significant amounts of IFN‐γ and TNF‐α and no IL‐4. Finally, studies with sera from patients resistant to infection and living in schistosomiasis endemic areas revealed high levels of specific IgG to both chimeras when compared to healthy individuals. In conclusion, SmTSP‐2/Sm29 chimeras tested here induced partial protection against infection and might be a potential vaccine candidate.  相似文献   
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目的 探讨不同浓度葡萄糖对小鼠海马神经元细胞系 HT-22细胞凋亡的作用及机制。方法 体外培养小鼠海马神经元 HT-22细胞,使用不同浓度的高糖培养液(25、35、45、55、65、75 mmol/L)分别作用细胞 24、48、72 h,以 25 mmol/L 糖浓度为对照组,其余组为实验组。采用 CCK-8 法检测各组细胞活力变化,筛选出最佳作用时间。HT-22细胞经不同浓度葡萄糖作用 48 h后,微板法检测细胞培养上清液中乳酸脱氢酶(LDH)释放率;光学显微镜观察细胞形态变化;流式细胞术检测各组细胞凋亡情况;蛋白免疫印迹法(Western blot)检测 Bcl-2、Bax蛋白表达量的变化。结果 CCK-8结果显示,高糖可抑制 HT-22细胞的活力,其抑制作用具有剂量和时间依赖性。高糖作用时间48 h时,细胞活力≥80%,可满足后续实验要求。随着葡萄糖浓度的增高,出现细胞数目减少,胞体变大,部分胞核溶解,突触断裂等改变,并且 LDH释放率及凋亡率也明显增高(P<0.05),Western blot结果显示凋亡蛋白 Bcl-2表达下降(P<0.05),Bax表达增高(P<0.05)。结论 高糖能显著抑制 HT-22细胞生长和活力,诱导细胞凋亡,其作用机制可能与 Bcl-2、Bax表达有关。  相似文献   
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The high mortality rates associated with cancer reflect the metastatic spread of tumor cells from the site of their origin. Metastasis, in fact, is the cause of 90% of cancer deaths. Therefore, considerable effort is being made to inhibit metastasis. In the present study, we screened ketotifen for anti-migratory and anti-invasive activities against MDA-MB-231 breast cancer and HT-1080 fibrosarcoma cancer cells. Cancer cell migration and invasion were measured using multi-well chambers. Additionally, western blots were used to examine the effects of ketotifen on the expressions of CDC42, Rho, Rac, and matrix metalloproteinase 9 (MMP-9). The results showed that ketotifen dose-dependently suppressed the migration and invasion of MDA-MB-231 and HT-1080 cells. Ketotifen also suppressed the expressions of CDC42, Rac, and Rho, which, significantly, are involved in MDA-MB-231 and HT-1080 cancer cell migration. Moreover, ketotifen suppressed the expression and activity of MMP-9, which is involved in degradation of the extracellular matrix leading to invasion. The overall data suggested that ketotifen suppresses the migration and invasion of MDA-MB-231 and HT-1080 cancer cells via inhibition of CDC42, Rac, Rho, and MMP-9 expression.  相似文献   
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Microglial inflammation is identified as a key process associated with Parkinson's disease (PD) pathogenesis. Our previous study showed that miR‐29c‐3p (miR‐29c) exhibited anti‐inflammatory properties in PD animal and neuronal models. However, the specific role and regulatory mechanism of miR‐29c played in microglia are still unclear. In this study, lipopolysaccharide (LPS)‐stimulated BV‐2 cells were used to establish a cellular model of microglial activation for investigating PD. The results showed a decreased expression of miR‐29c in LPS‐induced BV‐2 cells. Over‐expression of miR‐29c suppressed LPS‐triggered Iba‐1 increment, pro‐inflammatory cytokine release, and NF‐кB and TXNIP/NLRP3 inflammasome activation. Silence of miR‐29c induced similar effects with LPS on microglial inflammation. In addition, we found that NFAT5 was negatively correlated with miR‐29c. Knockdown of NFAT5 blocked the aggravated inflammation in microglia treated by miR‐29c inhibitor. Thus, these findings suggest that miR‐29c modulates NLRP3 inflammasome to impair microglial inflammatory responses by targeting NFAT5, which represents a promising therapeutic target for PD.  相似文献   
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Ovarian cancer (OC) is one of the most aggressive female cancers in the world. OC trends to be diagnosed at an advanced stage with abdominal metastasis. Our study explored the biological function and underlying mechanism of lncRNA on OC cell proliferation and migration. The expression of turine up-regulated gene 1 (TUG1) in human OC tissues and cell lines was measured by qRT-PCR. OC cell proliferation, viability, migration, and invasion were measured by MTT assays, colony formation assays, and transwell assays in vitro. Furthermore, the nude mice xenograft model was established to determine the effects of TUG1 in vivo. The relationship between TUG1 and miR-29b-3p, as well as miR-29b-3p and MDM2 were identified using the luciferase reporter assays. We showed that the expression of TUG1 and MDM2 were significantly increased, but the expression of miR-29b-3p was remarkably decreased in OC tissues and cell lines. Knockdown of TUG1 strongly inhibited the ability of cell proliferation, colony formation, migration, and invasion in vitro. The relationship between TUG1 and miR-29b-3p, or miR-29b-3p and MDM2 were predicted by StarBase and miRanda online software. Besides, miR-29b-3p reversed the positive effect of TUG1 on the OC cell proliferation, migration, and invasion through inhibiting MDM2 expression and increasing p53 phosphorylation level. Moreover, knockdown of TUG1 suppressed tumor growth in vivo. Taken all together, this study shows that TUG1 plays a crucial oncogenic role and facilitates cell proliferation, migration, and invasion in OC through regulating miR-29b-3p/MDM2 axis.  相似文献   
90.
目的探讨不同类型肠易激综合征(IBS)患者血清微小RNA(miRNA)-144、miRNA-29a和miRNA-200a表达水平的相关性及临床意义,为IBS的病因学研究提供理论依据。方法采用病例抽样的方法选取2015年10月至2018年6月该院IBS患者110例,选取同期110例体检健康者为健康对照组。受试者采样前12 h低蛋白饮食,每位受试者取10 mL静脉血样本,静脉血3000 r/min离心后取上清。采用实时荧光定量反转录PCR测定受试者miRNA-144、miRNA-29a和miRNA-200a表达水平。结果混合型IBS的miRNA-144、miRNA-29a和miRNA-200a表达水平均显著高于其他3种亚型(P<0.05),不确定型IBS的miRNA-144、miRNA-29a和miRNA-200a表达水平均显著高于便秘型IBS及腹泻型IBS(P<0.05)。混合型、不确定型IBS患者的miRNA-144、miRNA-29a、miRNA-200a的表达水平两两之间均存在相关性且有统计学意义(P<0.05),但对于单纯腹泻或者便秘型IBS患者来说,仅miRNA-29a与miRNA-200a的表达水平存在统计学相关性(P<0.05)。结论混合型、不确定型IBS患者血清miRNA-144、miRNA-29a和miRNA-200a表达水平较其他2种亚型高,且血清miRNA-144、miRNA-29a和miRNA-200a表达两两之间具有显著相关性。  相似文献   
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