miR-106a对小鼠卵巢癌移植瘤生长的影响研究

目的研究miR-106a对小鼠卵巢癌移植瘤生长的影响。方法选择SPF级BALB/c小鼠作为实验动物,将SKOV3卵巢癌细胞注入小鼠皮下以复制卵巢癌移植瘤模型,将模型小鼠随机分为空白对照组、阴性对照组、miR-106a抑制组,分别用不含抑制剂的转染试剂、含阴性对照抑制剂的转染试剂、含miR-106a抑制剂的转染试剂进行干预,干预前及干预后分别测定移植瘤体积以及移植瘤中PTEN信号通路分子的表达量。结果干预后10、20、30和40d时,空白对照组、阴性对照组、miR-106a抑制组之间瘤体体积的比较差异有统计学意义(P<0.05),每组内不同时间点的比较差异有统计学意义(P<0.05),组间与时间变化趋势的比较差异有统计学意义(P<0.05);干预后40d时,miR-106a抑制组小鼠肿瘤组织中PTEN的mRNA表达高于空白对照组和阴性对照组,PI3K、AKT、CyclinD1、Survivin、MMP-2、MMP-9、VEGF的mRNA表达低于空白对照组和阴性对照组。结论miR-106a对小鼠卵巢癌移植瘤的生长具有抑制作用,增强PTEN信号通路是miR-106a抑制肿瘤生长的分子机制。

Influence of multi-pass friction stir processing on microstructure and mechanical properties of 7B04-O Al alloy

Three-pass friction stir processing(FSP)with different moving distances of the stirring tool between the two successivepasses,50%diameter of the pin(traditional way)and50%diameter of the shoulder(novel way),was conducted on7B04-O Al alloy.The result shows that an improvement in the mechanical properties of the processed zone is accomplished due to grain and secondphase particles refinement.The hardness of the multi-pass FSP(M-FSP)sample is about HV40higher than that of the base metal.And the tensile strength of the M-FSP specimens is also significantly increased to about1.4times that of the base metal.Besides,theweak region of the processed zone is mainly dependent on the moving distance,where it is the previous pass stir zone in thetraditional way and the transitional zone in the novel way.Increasing the rotational speed narrows the weak region in the novel way,while it does not in the traditional way.

Experimental study on the inhibition effect of miR-106a inhibitor on tumor growth of ovarian cancer xenografts mice

Objective:To study the inhibition effect of miR-106 a inhibitor on tumor growth of ovarian cancer xenografts mice.Methods:BALB/c mice were selected as experimental animals,ovarian cancer SKOV-3 cells transfected with miR-106 a inhibitor and its negative control were inoculated subcutaneously,intratumoral injection of miR-106 a inhibitor and its negative control were continued after tumor formation,and they were enrolled as treatment group and model group,respectively.Tumor volume and weight as well as Ki-67 and programmed cell death 4(PDCD4) expression were determined;miR-106 a inhibitor and its negative control as well as miR-106 a mimic and its negative control were transfected into SKOV-3 cells,and expression of PDCD4 in cells was determined.Results:Tumor tissue volume and weight as well as mR NA expression and protein expression of Ki-67 in treatment group were significantly lower than those in the model group while m RNA expression and protein expression of PDCD4 were significantly higher than those in the model group;transfection of mi R-106 a mimic could decrease m RNA expression and protein expression of PDCD4 in SKOV-3 cells,and transfection of miR-106 a inhibitor could increase mR NA expression and protein expression of PDCD4 in SKOV-3 cells.Conclusions:Transfection of mi R-106 a inhibitor can inhibit the growth of tumor in ovarian cancer xenografts mice through increasing the expression of PDCD4.

Early Cretaceous deformation in the southern Tashkorgan region: Implications for the tectonic evolution of the northeastern Pamir

The Pamir Plateau comprises a series of crustal fragments that successively accreted to the Eurasian margin preceded the India-Asia collision,is an ideal place to study the Mesozoic tectonics.The authors investigate the southern Tashkorgan area,northeastern Pamir Plateau,where Mesozoic metamorphic and igneous rocks are exposed.New structural and biotite ^(40)Ar-^(39)Ar age data are presented.Two stages of intense deformation in the metamorphic rocks are identified,which are unconformably covered by the Early Cretaceous sediment.Two high-grade metamorphic rocks yielding 128.4±0.8 Ma and 144.5±0.9 Ma ^(40)Ar-^(39)Ar ages indicate that the samples experienced an Early Cretaceous cooling event.Combined with previous studies,it is proposed that the Early Cretaceous tectonic records in the southern Tashkorgan region are associated with Andean-style orogenesis.They are the results of the flat/low-angle subduction of the Neotethyan oceanic lithosphere.

Correlation of miR-451 expression with proliferation and apoptosis gene expression in ovarian cancer

Objective: To study the correlation of miR-451 expression with proliferation and apoptosis gene expression in ovarian cancer. Methods: The patients with ovarian cancer who underwent surgical resection in our hospital between March 2015 and February 2018 were selected, ovarian cancer lesions and adjacent lesions were collected, miRNA was isolated to determine the expression of miR-451, and mRNA was isolated to determine the mRNA expression of cyclin, proliferation genes and apoptosis genes. Results: The expression of miR-451 as well as the mRNA expression of Cyclin-dependent kinase inhibitor 1B (p27Kip1), BCL2-associated X protein (Bax), factor associated suicide (Fas), Fas ligand (FasL), cysteine aspartyl proteinase 3 (Caspase-3) and CCAAT/enhancer-binding protein homologous protein (CHOP) in ovarian cancer lesions was significantly lower than those in adjacent lesions while the mRNA expression of CyclinB1, CyclinD1, CyclinE, phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), β-catenin, matrix metalloproteinase 2 (MMP2) and matrix metalloproteinase 9 (MMP 9) were significantly higher than those in adjacent lesions;miR-451 in ovarian cancer was negatively correlated with CyclinB1, CyclinD1, CyclinE, PI3K, AKT, β-catenin, MMP2 and MMP9 mRNA expression, and positively correlated with p27Kip1, Bax, Fas, FasL, Caspase-3 and CHOP mRNA expression. Conclusion: The low expression of miR-451 in ovarian cancer is closely correlated with the high expression of positive cell cycle regulatory proteins and proliferation genes as well as the low expression of negative cell cycle regulatory proteins and apoptosis genes, and it may be the key factor to promote the growth of ovarian cancer.

Research progress in the use of bifidobacteria for the treatment of colorectal cancer

Colorectal cancer has high morbidity and mortality rates;therefore,developing new therapeutic drugs and methods for it is crucial.There is increasing evidence that intestinal flora plays a vital role in maintaining intestinal homeostasis and therefore,in the development of colorectal cancer.As such,therapeutic approaches using probiotics such as Bifidobacterium lactis to regulate intestinal flora are expected to represent a new treatment strategy for colorectal cancer.This article introduces and compares the development status of conventional therapies for colorectal cancer,primarily targeted therapy and immunotherapy,the relationship between intestinal flora and colorectal cancer,and the research and application of Bifidobacterium bifidum in colorectal cancer treatment to provide a reference for its clinical application.