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91.
绝经后骨质疏松症(PMO)是一种多基因调控的遗传性疾病。雌激素受体β亚型基因是骨质疏松症的重要侯选基因。此文采用病例对照设计(78名股骨颈PMO病人和122名对照以及108名腰椎PMO病人和92名对照)研究中国人(汉族)雌激素受体β基因(ESR2)第5内含子CA重复序列多态性与PMO的相关性。以CA重复序列平均数22次为界将重复序列基因分为短基因(<22)和长基因(≥22),分别以S和L表示。股骨颈及腰椎(L2-4)部位,病例组中LL基因型和L等位基因者频率显著高于对照组(P<0.01),SL、LL及SL LL基因型者较SS基因型者患PMO风险显著增高(P<0.05);调整年龄、绝经时间、绝经年龄及体质指数后,Logistic回归分析显示ESR2(CA)n多态性仍然与股骨颈(OR4.923,95%CI1.986~12.203,P=0.001)及L2-4(OR2.267,95%CI1.121~4.598,P=0.023)PMO显著相关。结果显示:ESR2基因CA重复序列多态性与股骨颈和L2-4部位PMO独立关联,L等位基因显性影响PMO的发病风险。 相似文献
92.
Two new tetralones, pyrolones A (1) and B (2), and a new flavonol glycoside, 2'-O-(4-hydroxybenzoyl)hyperin (3), were isolated from Pyrola calliantha (whole plant), together with six structurally related compounds, including 2'-O-galloylhyperin (4), hyperin (5), formononetin (6), quercetin 3-O-alpha-L-arabinopyranoside (7), quercetin 3-O-alpha-L-arabinofuranoside (8), and kaempferol 3-O-beta-D-galactopyranoside (9). The structures and absolute configurations of the new compounds were elucidated on the basis of spectroscopic (UV, ORD, CD, NMR) and mass-spectrometric (HR-ESI-MS) analyses. 相似文献
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94.
环状RNA(circular RNA, circRNA)作为竞争性内源RNA(competitive endogenous RNA, ceRNA)在细胞分化调控中发挥着重要作用。本研究旨在对猪环状RNA IGF1R(circular RNA insulin-like growth factor 1 receptor, circIGF1R)进行鉴定及分析,探明其表达规律,构建猪circIGF1R相关的ceRNA调控网络,并探究其异位表达对小鼠间充质干细胞(C3H10T1/2)成脂分化的调控作用。通过正反向引物PCR、Sanger测序、RNase R酶消化检测和qRT-PCR验证circIGF1R是胰岛素样生长因子1受体(insulin-like growth factor 1 receptor, IGF1R)第二外显子形成的circRNA,它在猪各组织中均有表达,且其表达量在脂肪组织中随日龄增加呈上升趋势;使用miRDB、TargetScan和miRWalk在线软件预测circIGF1R靶基因,运用RNAhybrid软件进行结合位点预测,使用DAVID生物信息功能分析软件对候选靶基因进行GO和KEGG富集分析,运用Cytoscape软件构建ceRNA网络,基于基因表达相关性和预测的靶标关系,绘制了GO和KEGG富集分析及构建了ceRNA网络;双荧光素酶报告基因分析证明circIGF1R及FABP4可与ssc (Sus scrofa chromosome) -miR-133a-5p结合;成功构建circIGF1R过表达载体,在间充质干细胞C3H10T1/2中异位表达,过表达circIGF1R后关键成脂调控因子CEBPα、CEBPβ、FABP4和PPARγ极显著升高(P<0.01),脂滴数量显著增加。本研究结果证明,circIGF1R在猪脂肪组织中存在,并且可能通过ceRNA机制正调控C3H10T1/2细胞成脂分化,为进一步研究circIGF1R调控猪前体肌内脂肪细胞成脂分化奠定理论基础。 相似文献
95.
Wu Yuru Chen Jiehao Wei Wenyan Miao Yujia Liang Chao Wu Jianing Huang Xiaoli Yin Lizi Geng Yi Chen Defang Ouyang Ping 《International microbiology》2022,25(3):605-613
International Microbiology - Aeromonas hydrophila is a common pathogen in fish that has caused severe economic losses in aquaculture worldwide. With the emergence of bacterial resistance, it is... 相似文献
96.
Peng-Fei Zhang Fei Wang Jing Wu Yin Wu Wei Huang Dong Liu Xiao-Yong Huang Xue-Mei Zhang Ai-Wu Ke 《Journal of cellular physiology》2019,234(3):2788-2794
Dysregulation of long noncoding RNAs (lncRNAs) plays important roles in carcinogenesis and tumor progression, including hepatocellular carcinoma (HCC). Small nucleolar RNA host gene 3 (SNHG3) has been considered as an lncRNA to be associated with a poor prognosis in patients with HCC. Here, we reported that SNHG3 expression was significantly higher in the highly metastatic HCC (HCCLM3) cells compared with the lowly metastatic HCC cells (Hep3B and PLC/PRF/5). Furthermore, forced expression of SNHG3 promoted cell invasion, epithelial-mesenchymal transition (EMT), and sorafenib resistance in HCC. Moreover, SNHG3 overexpression induced HCC cells EMT via miR-128/CD151 cascade activation. Clinically, our data revealed that increased SNHG3 expression is correlated with poor HCC survival outcomes and sorafenib response. These data suggest that SNHG3 may be a novel therapeutic target and a biomarker for predicting response to sorafenib treatment of HCC. 相似文献
97.
Ting Yi Min Liu Xueyan Li Xueqing Liu Yubin Ding Junlin He Hanting Xu Rufei Gao Xinyi Mu Yanqing Geng Yingxiong Wang Xuemei Chen 《Journal of cellular physiology》2019,234(7):11119-11129
Benzo(a)pyrene (BaP) is an endocrine-disrupting pollutant present in various aspects of daily life, and studies have demonstrated that BaP exerts reproductive toxicity. We previously showed that BaP damages endometrial morphology and decreases the number of implantation sites in early pregnant mice, but the mechanisms underlying these effects remain unclear. The endometrial function is crucial for implantation, which is associated with endometrial cell apoptosis. In this study, we focused on the effect of BaP on endometrial cell apoptosis and the role of WNT signaling during this process. Pregnant mice were gavaged with corn oil (control group) or 0.2 mg·kg−1·day −1 BaP (treatment group) from Days 1 to 6 of pregnancy. BaP impaired endometrial function by decreasing the expression of HOXA10 and BMP2, two markers of receptivity and decidualization. WNT5A and β-catenin were activated in the BaP group. BaP affected the expression of apoptosis-related proteins and inhibited the apoptosis of endometrial stromal cells. In vitro, human endometrial stromal cells (HESCs) were treated with different concentrations of BaP (dimethyl sulfoxide (DMSO); 5, 10 µM). WNT5A and β-catenin were also upregulated in the BaP treatment group. HESC apoptosis was restrained by BaP. Inhibiting WNT5A by SFRP5 partially restored the effect of BaP on apoptosis. In summary, these results suggested that BaP exposure during early pregnancy activates WNT5A/β-catenin signaling pathway, which inhibits the endometrial cell apoptosis and potentially destroys endometrial function. 相似文献
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99.
He Pei Wu Long-Fei Bing Peng-Fei Xia Wei Wang Lan Xie Fang-Fei Lu Xin Lei Shu-Feng Deng Fei-Yan 《Molecular and cellular biochemistry》2019,450(1-2):135-147
Molecular and Cellular Biochemistry - The immune responses, involved in recognition of cancer-specific antigens, are of particular interest as this may provide major leads towards developing new... 相似文献
100.
Li Yanman Qu Ying Wang Yang Bai Xue Tian Geng Liu Zhirou Li Yonghua Zhang Kaiming 《Molecular biology reports》2019,46(6):6027-6037
Molecular Biology Reports - Begonia semperflorens (B. semperflorens), belonging to the family Begoniaceae, has now been widely cultivated worldwide and is famous for its ornamental plants with... 相似文献