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101.
A protein-free, isothermal, self-amplified nucleic acid sensing system which was a G-quadruplex integrated hybridization chain reaction (GQ-HCR) system was developed. The G-quadruplex was closed two-thirds in the loop and one-third in the stem of one of the GQ-HCR hairpin probes. In the absence of the target molecule, the GQ-HCR probes stayed as inactive meta-stable hairpin structures and the G-quadruplex was inert. Reversely, the GQ-HCR probes could be cross-opened to start a hybridization chain reaction and the closed G-quadruplex could be released to be free when the GQ-HCR probes came across the target molecule. The GQ-HCR nucleic acid sensing system could detect as low as 7.5nM ssDNA or RNA by the colorimetric method and 4nM ssDNA by the fluorometric method. Less than 10 copies of dsDNA template could also be detected when PCR was combined with the GQ-HCR system (PCR+GQ-HCR). Because of these advantages, the GQ-HCR system was also studied for application in visual chip detection to obtain a satisfactory repeatable and specific result. 相似文献
102.
越桔亚科植物化学成分研究进展 总被引:2,自引:0,他引:2
本文综述了近年来越桔亚科植物的研究进展。分别介绍了越桔属,红梅苔子属等化学成分研究的概况。 相似文献
103.
STIP overexpression confers oncogenic potential to human non‐small cell lung cancer cells by regulating cell cycle and apoptosis 下载免费PDF全文
Yani Tang Guobei Yan Xin Song Kuangpei Wu Zhen Li Chao Yang Tanggang Deng Yang Sun Xiaoxiao Hu Cai Yang Huarong Bai Hui Li Weihong Tan Mao Ye Jing Liu 《Journal of cellular and molecular medicine》2015,19(12):2806-2817
Sip1/tuftelin‐interacting protein (STIP), a multidomain nuclear protein, is a novel factor associated with the spliceosome, yet its role and molecular function in cancer remain unknown. In this study, we show, for the first time, that STIP is overexpressed in non‐small cell lung cancer (NSCLC) tissues compared to adjacent normal lung tissues. The depletion of endogenous STIP inhibited NSCLC cell proliferation in vitro and in vivo, caused cell cycle arrest and induced apoptosis. Cell cycle arrest at the G2/M phase was associated with the expression and activity of the cyclin B1‐CDK1 (cyclin‐dependent kinase 1) complex. We also provide evidence that STIP knockdown induced apoptosis by activating both caspase‐9 and caspase‐3 and by altering the Bcl‐2/Bax expression ratio. RNA sequencing data indicated that the MAPK mitogen‐activated protein kinases, Wnt, PI3K/AKT, and NF‐κB (nuclear factor kappa‐light‐chain‐enhancer of activated B cells) signalling pathways might be involved in STIP‐mediated tumour regulation. Collectively, these results suggest that STIP may be a novel potential diagnostic and therapeutic target for NSCLC. 相似文献
104.
Sprague-Dawley albino rats or Long-Evans pigmented rats were exposed during the dark phase of the daily light:dark cycle to various intensities of a sunlight-stimulating white fluorescent light (0.022, 0.044, 0.110, 0.220, 0.440 or 2.200 μW/cm2) for 30 min; pineal glands and trunk blood samples were then collected and assayed for melatonin by radioimmunoassay. Albino rats exposed to irradiances of 0.110 μW/cm2 or less had pineal melatonin levels that were not significantly different from those of unexposed animals; higher irradiances significantly (P < 0.001) reduced melatonin levels. In contrast, as little as 0.022 μW/cm2 significantly (P < 0.02) reduced pineal and serum melatonin levels in the pigmented rats. These results suggest that something other than the simple presence or absence of eye pigmentation is the critical factor in determining the sensitivity of the rat's pineal to retinal-mediated photic suppression of melatonin synthesis. 相似文献
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107.
Ling Li Tanggang Deng Lin Zhang Yanpeng Wang Yangyang Zhou Yan Liu Hui Li Jing Dai Yuan Yang Neng Ling Huimin Liu Jing Liu Lanqin Cao Min Xu Mao Ye 《International journal of biological sciences》2022,18(6):2568
Breast cancer ranks as the most frequently diagnosed cancer among women worldwide. Elevated cytoplasmic p21 levels are often found in breast cancer tissues and related to a poor prognosis. However, the underlying mechanisms that lead to the stabilization of cytoplasmic p21 protein, which normally has a very short half-life, remain obscure. In this study, we found that there was a strong correlation between p21 and USP11 in the cytoplasm of breast cancer tissues and cells. Furthermore, we revealed that ERK1/2 phosphorylated USP11 at the Ser905 site, which promoted the cytoplasmic localization of USP11. In the cytoplasm, USP11 colocalized and interacted with p21. As a result, USP11 catalyzed the removal of polyubiquitin chains bound to cytoplasmic p21 and resulted in its stabilization. Functionally, USP11-mediated stabilization of cytoplasmic p21 induced breast cancer cell proliferation in vitro and in vivo. Our findings provide the first evidence that ubiquitinated p21 in the cytoplasm can be recycled through USP11-mediated deubiquitination, and we identified the USP11-p21 axis in the cytoplasm as a potential therapeutic target for breast cancer control. 相似文献
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109.
Ling Deng Jie Chen Xiao Rong Zhong Ting Luo Yan Ping Wang Hui Fen Huang Li-Juan Yin Yan Qiu Hong Bu Qing Lv Hong Zheng 《PloS one》2015,10(3)
Background
Abnormal activation of PI3K/AKT/mTOR (PAM) pathway, caused by PIK3CA mutation, KRAS mutation, PTEN loss, or AKT1 mutation, is one of the most frequent signaling abnormalities in breast carcinoma. However, distribution and frequencies of mutations in PAM pathway are unclear in breast cancer patients from the mainland of China and the correlation between these mutations and breast cancer outcome remains to be identified.Methods
A total of 288 patients with invasive ductal breast cancer were recruited in this study. Mutations in PIK3CA (exons 4, 9 and 20), KRAS (exon 2) and AKT1 (exon 3) were detected using Sanger sequencing. PTEN loss was measured by immunohistochemistry assay. Correlations between these genetic aberrations and clinicopathological features were analyzed.Results
The frequencies of PIK3CA mutation, KRAS mutation, AKT1 mutation and PTEN loss were 15.6%, 1.8%, 4.4% and 35.3%, respectively. However, except for PTEN loss, which was tied to estrogen receptor (ER) status, these alterations were not associated with other clinicopathological features. Survival analysis demonstrated that PIK3CA mutation, PTEN loss and PAM pathway activation were not associated with disease-free survival (DFS). Subgroup analysis of patients with ER positive tumors revealed that PIK3CA mutation more strongly reduced DFS compared to wild-type PIK3CA (76.2% vs. 54.2%; P = 0.011). PIK3CA mutation was also an independent factor for bad prognosis in ER positive patients.Conclusions
AKT1, KRAS and PIK3CA mutations and PTEN loss all exist in women with breast cancer in the mainland China. PIK3CA mutation may contribute to the poor outcome of ER positive breast carcinomas, providing evidence for the combination of PI3K/AKT/mTOR inhibitors and endocrine therapy. 相似文献110.
Liyuan Tian Xiaojie Wu Yanli Lin Zhuguo Liu Fuyin Xiong Zhengbin Han Yanrong Zhou Qiangcheng Zeng Yumin Wang Jixian Deng Hongxing Chen 《Molecular reproduction and development》2009,76(7):656-664
Members of the super‐class of zinc finger proteins are key regulators in early embryogenesis. Utilizing in silico mining of EST Databases for pre‐implantation Embryo‐Specific Zinc Finger Protein Genes, we characterized a novel zygotic mouse gene—tripartite motif family‐like 1 (TRIML1), which expresses in embryo before implantation. Knocking down of TRIML1 resulted in the fewer cell number of blastocysts and failture to give rise to neonates after embryo transfer. The binding partner of TRIML1, Ubiquitin‐specific protease 5 (USP5), was identified by yeast two‐hybrid screening assay. The interaction was confirmed by GST pull‐down and coimmunoprecipitation analysis. The role of TRIML1 in ubiquitin pathway during the development stage of mouse blastocyst was further discussed. Mol. Reprod. Dev. 76: 656–664, 2009. © 2009 Wiley‐Liss, Inc. 相似文献