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61.
Ran Liu Miao Yang Yanli Meng Juan Liao Jingyi Sheng Yuepu Pu Lihong Yin Sun Jung Kim 《PloS one》2013,8(10)
Recent studies have demonstrated the possible function of miR-139-5p in tumorigenesis. However, the exact mechanism of miR-139-5p in cancer remains unclear. In this study, the association of miR-139-5p expression with esophageal squamous cell carcinoma (ESCC) was evaluated in 106 pairs of esophageal cancer and adjacent non-cancerous tissue from ESCC patients. The tumor suppressive features of miR-139-5p were measured by evaluating cell proliferation and cell cycle state, migratory activity and invasion capability, as well as apoptosis. Luciferase reporter assay and Western blot analysis were performed to determine the target gene regulated by miR-139-5p. The mRNA level of NR5A2, the target gene of miR-139-5p, was determined in ESCC patients. Results showed that reduced miR-139-5p level was associated with lymph node metastases of ESCC. MiR-139-5p was investigated to induce cell cycle arrest in the G0/G1 phase and to suppress the invasive capability of esophageal carcinoma cells by targeting the 3′UTR of oncogenic NR5A2. Cyclin E1 and MMP9 were confirmed to participate in cell cycle arrest and invasive suppression induced by NR5A2, respectively. Pearson correlation analysis further confirmed the significantly negative correlation between miR-139-5p and NR5A2 expression. The results suggest that miR-139-5p exerts a growth- and invasiveness-suppressing function in human ESCCs, which demonstrates that miR-139-5p is a potential biomarker for early diagnosis and prognosis and is a therapeutic target for ESCC. 相似文献
62.
Solar Cells: Synergic Interface Optimization with Green Solvent Engineering in Mixed Perovskite Solar Cells (Adv. Energy Mater. 20/2017) 下载免费PDF全文
63.
Hai Hu Hong Li Feng Jiao Ting Han Meng Zhuo Jiujie Cui Yixue Li Liwei Wang 《Journal of hematology & oncology》2017,10(1):158
Background
Multiple primary cancers (MPC) have been identified as two or more cancers without any subordinate relationship that occur either simultaneously or metachronously in the same or different organs of an individual. Lynch syndrome is an autosomal dominant genetic disorder that increases the risk of many types of cancers. Lynch syndrome patients who suffer more than two cancers can also be considered as MPC; patients of this kind provide unique resources to learn how genetic mutation causes MPC in different tissues.Methods
We performed a whole genome sequencing on blood cells and two tumor samples of a Lynch syndrome patient who was diagnosed with five primary cancers. The mutational landscape of the tumors, including somatic point mutations and copy number alternations, was characterized. We also compared Lynch syndrome with sporadic cancers and proposed a model to illustrate the mutational process by which Lynch syndrome progresses to MPC.Results
We revealed a novel pathologic mutation on the MSH2 gene (G504 splicing) that associates with Lynch syndrome. Systematical comparison of the mutation landscape revealed that multiple cancers in the proband were evolutionarily independent. Integrative analysis showed that truncating mutations of DNA mismatch repair (MMR) genes were significantly enriched in the patient. A mutation progress model that included germline mutations of MMR genes, double hits of MMR system, mutations in tissue-specific driver genes, and rapid accumulation of additional passenger mutations was proposed to illustrate how MPC occurs in Lynch syndrome patients.Conclusion
Our findings demonstrate that both germline and somatic alterations are driving forces of carcinogenesis, which may resolve the carcinogenic theory of Lynch syndrome.64.
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66.
Repression of microRNA‐382 inhibits glomerular mesangial cell proliferation and extracellular matrix accumulation via FoxO1 in mice with diabetic nephropathy 下载免费PDF全文
67.
黑色素是一种广泛存在于动物、植物、细菌及真菌中的生物色素,具有多种生物功能及良好的生物活性。黑木耳以“黑”出名,其富含的黑色素具有广阔开发应用价值。本研究旨在评价黑木耳黑色素对急性肝损伤的改善作用。首先应用傅里叶红外光谱初步对提取的黑木耳黑色素进行鉴定,再通过DPPH自由基及羟基自由基清除实验证实提取的黑木耳黑色素体外抗氧化能力,并进一步以四氯化碳致小鼠急性肝损伤为模型,通过检测血清酶指标、肝功指标的变化及病理切片情况,来评价黑木耳黑色素体内抗氧化及保肝效果。结果表明,提取的黑木耳黑色素具有黑色素特征的官能团结构和良好的体外抗氧化能力,对DPPH自由基和羟基(OH)自由基清除的EC50分别为0.0887mg/mL、2.2030mg/mL;动物体内实验中,与模型组对比,给药组(黑木耳黑色素)的小鼠血清中ALT、AST含量显著降低(P<0.01),肝脏中MDA含量显著降低(P<0.01)和SOD活性显著升高(P<0.01),并且肝细胞病理状态明显改善。本文报道了黑木耳黑色素在体内能有效改善四氯化碳诱导的小鼠肝损伤,为黑木耳的功能产品开发提供了新思路和研究基础。 相似文献
68.
乳链球菌SB900胞壁肽聚糖的部分生物学活性 总被引:6,自引:0,他引:6
对乳链球菌(Streptococcuslactis)SB900胞壁肽聚糖(简称为LABPG)进行了分离纯化及化学成分分析,并测定了其部分生物学活性.结果表明,LABPG蛋白质含量为9.84%,NAG0.871μmol/mg,NAM1.14μmol/mg;氨基酸分析结果表明,Ala、Glu、Asp含量较高,分别为1.046、0.775、0.304μmol/mg。以小鼠为实验材料进行动物学实验,对LABPG的生物学活性测定结果表明,LANPG无毒、安全可靠;腹腔注射LABPG后,PMΦ数目增多,吞噬功能明显增强,血清溶菌酶活性增强;YC-花环实验表明,腹腔注射LABPG的小鼠PMΦ表面C3b受体活性增强,YC-花环形成率较高,统计学分析有显著差别。说明LABPG对于MΦ有一定的激活作用,可作为机体的免疫激活剂。 相似文献
69.
70.
Meng Xue Mu Fangfang Zhang Zeyu Wu Xinru Gao Tiantian Zhao Fenglan Xue Jianping Duan Yongbo Zhang Haijun 《Plant Cell, Tissue and Organ Culture》2021,146(3):473-482
Plant Cell, Tissue and Organ Culture (PCTOC) - Vitex negundo L. var. cannabifolia (Sieb. et Zucc.) Hand.-Mazz. is an important medicinal plant rich in bioactive compounds. In vitro tissue culture... 相似文献