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101.
目的:探讨长链非编码RNA(lncRNA)CASC11和原癌基因c-myc在结直肠癌中的表达及其与复发转移的相关性。方法:收集2016年2月至2018年7月河北省唐山市协和医院收治的90例结直肠癌患者的癌组织及癌旁组织标本,体外培养正常结肠上皮细胞株CCD841及结直肠癌细胞株SW480、SW620、HCT116、HT...  相似文献   
102.
用~H-Lcu参入的方法,观察到小鼠腹水型Tu—RNA能显著地抑制小鼠脾淋巴细胞的蛋白质合成。这种抑制效应无RNA来源的肿瘤特异性,但具有组织特异性。主要活性成分可能存在于RNasc酶解混合物的Scphadex G—100层析第二组分中。  相似文献   
103.
BackgroundIt is considered that circRNA can participate in regulating the occurrence and effects of ventricular arrhythmia (VA) through competing endogenous RNA (ceRNA) mechanism, regulating pre-mRNA and regulating parental gene expression. Therefore, we used animal modeling and high-throughput differential screening to screen out circRNA related to VA and study its possible mechanism of action on VA.MethodsThe rat model of myocardial ischemia VA was established. High-throughput screening of the differentiated circRNA was conducted and verified by real-time quantitative polymerase chain reaction (qRT-PCR) and Western blot. Lv-circRNA01724 lentivirus was constructed using molecular biology. Primary isolation of the rat cardiomyocytes, hypoxia modeling, Lv-circRNA01724 transfection, mode of action verification, and dual luciferase detection of circRNA01724 and miR-323-5p was performed.ResultsThrough qRT-PCR verification of circRNA01724, circRNA02230, circRNA02088, miR-323-5p, miR-330-5p, and miR-324-3p expressions, circRNA01724 was selected as the research object. Detection by Western blot showed significantly lower Cx43, ZO-1, and α-catenin expressions in rat myocardial tissue in the model group compared with the control group at 1, 7, 14, and 28 days old. On identification of the isolated primary rat cardiomyocytes by immunofluorescence, the α-SMA characteristic protein expression indicated that the isolation was successful. Verification of rat cardiomyocytes transfected with Lv-circRNA01724 suggested overexpression in cells. The miR-323-5p was also highly expressed in the rat cardiomyocyte hypoxia model following Lv-circRNA01724 transfection. Detection by flow cytometry showed that modeling of the transfected Lv-circRNA01724 had a significant increased apoptotic rate. Detection by Western blot showed that modeling of the transfected Lv-circRNA01724 cells had significantly decreased Cx43, ZO-1, and α-catenin compared with the model group.ConclusionsHigh-throughput screening of circRNA01724 can promote the apoptosis of hypoxic cardiomyocytes, which is related to the rat model of myocardial ischemia VA and may be a potential target for the treatment of VA.  相似文献   
104.
目的观察靶向封闭CapG基因对胰腺癌细胞株BxPC3运动侵袭能力的影响。方法设计并体外合成靶向CapG的小干扰RNA,将其转染到BxPC3细胞中,蛋白质印迹法检测转染前后细胞中CapG蛋白的表达,采用Transwell小室检测转染前后细胞运动侵袭能力的改变。结果CapGsiRNA能有效降低BxPC3细胞中CapG的表达,CapG在蛋白质水平的表达抑制率达80%左右。抑制BxPC3细胞中CapG的表达后,BxPC3细胞的运动侵袭能力明显下降,穿过人工基底膜的细胞数显著低于阴性对照组和空白对照组(P〈0.05)。结论封闭CapG表达能明显抑制胰腺癌细胞BxPC3在体外的运动侵袭能力。  相似文献   
105.
目的:检测lncRNA DNM3OS在喉鳞状细胞癌(laryngeal squamous cell carcinoma,LSCC)组织和LSCC细胞株中的表达及其临床意义,探讨其对LSCC TU177细胞体外增殖、迁移及侵袭的影响,并分析DNM3OS与EMT的关系.方法:从河北医科大学第四医院生物标本库选取2014年3...  相似文献   
106.
Thiamine pyrophosphate (TPP)-sensitive mRNA domains are the most prevalent riboswitches known. Despite intensive investigation, the complex ligand recognition and concomitant folding processes in the TPP riboswitch that culminate in the regulation of gene expression remain elusive. Here, we used single-molecule fluorescence resonance energy transfer imaging to probe the folding landscape of the TPP aptamer domain in the absence and presence of magnesium and TPP. To do so, distinct labeling patterns were used to sense the dynamics of the switch helix (P1) and the two sensor arms (P2/P3 and P4/P5) of the aptamer domain. The latter structural elements make interdomain tertiary contacts (L5/P3) that span a region immediately adjacent to the ligand-binding site. In each instance, conformational dynamics of the TPP riboswitch were influenced by ligand binding. The P1 switch helix, formed by the 5′ and 3′ ends of the aptamer domain, adopts a predominantly folded structure in the presence of Mg2+ alone. However, even at saturating concentrations of Mg2+ and TPP, the P1 helix, as well as distal regions surrounding the TPP-binding site, exhibit an unexpected degree of residual dynamics and disperse kinetic behaviors. Such plasticity results in a persistent exchange of the P3/P5 forearms between open and closed configurations that is likely to facilitate entry and exit of the TPP ligand. Correspondingly, we posit that such features of the TPP aptamer domain contribute directly to the mechanism of riboswitch-mediated translational regulation.  相似文献   
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108.
During 2011, 5 persons in the area of Lazio, Italy were infected with a monophyletic strain of hepatitis E virus that showed high sequence homology with isolates from swine in China. Detection of this genotype in Italy parallels findings in other countries in Europe, signaling the possible spread of strains new to Western countries.  相似文献   
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