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71.
Liao  Xiaodan  Zhao  Zhongpu  Li  Hui  Wu  Bo  Huo  Jiawei  Li  Lei  Li  Xue  Cao  Xinran  Xia  Min  Wang  Chunru  Bai  Chunli 《中国科学:生命科学英文版》2022,65(6):1146-1156

Ulcerative colitis (UC) is a long-term, recurrent inflammatory bowel disease for which no effective cure is yet available in the clinical setting. Repairing the barrier dysfunction of the colon and reducing intestinal inflammation are considered key objectives to cure UC. Here we demonstrate a novel therapeutic strategy based on a C60 fullerene suspension (C60FS) to treat dinitrobenzene sulfonic acid-induced UC in an animal model. C60FS can repair the barrier dysfunction of UC and effectively promote the healing of ulcers; it also manifests better treatment effects compared with mesalazine enema. C60FS can reduce the numbers of basophils in the blood of UC rats and mast cells in the colorectal tissue, thereby effectively alleviating inflammation. The expression of H1R, H4R, and VEGFR2 receptors in colorectal tissues is inhibited by C60FS, and the levels of histamine and prostaglandin in the rat blood are reduced. This work presents a reliable strategy based on fullerene to cure UC and provides a novel guide for UC treatment.

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72.
A new taxoid metabolite with a new substitution pattern was isolated from the methanol extract of the seeds of Taxus mairei, and its structure was established as 5alpha,15-dihydroxy-7beta,9alpha-diacetoxy-11(15-->1)abeo-taxa-4(20),11-dien-13-one (1) on the basis of spectral analysis including (1)H- and (13)C-NMR, HMQC, HMBC, NOESY, and confirmed by HR-FAB mass spectrometry.  相似文献   
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More and more documents have proved that the abnormal expression of long noncoding RNAs (lncRNAs) are correlated with the initiation and progression of colorectal cancer (CRC). lncRNA FOXD3-AS1 has been reported in glioma for its oncogenic property. According to the survival analysis of The Cancer Genome Atlas database, FOXD3-AS1 upregulation implied lower survival rate of patients with CRC. Quantitative real-time polymerase chain reaction showed the overexpression of FOXD3-AS1 in both CRC tissues and cells. The Kaplan–Meier method demonstrated the prognostic value of FOXD3-AS1 for patients with CRC. To explore the effect of FOXD3-AS1 on CRC progression, loss-of-function experiments were carried out, whose results indicated that knockdown of FOXD3-AS1 suppressed cell proliferation, migration, and invasion, inhibited cell cycle and promoted cell apoptosis in vitro. In vivo experiments affirmed that FOXD3-AS1 affected tumor growth. FOXD3-AS1 expression was enriched in the cytoplasm of CRC cells. Mechanism experiments revealed that FOXD3-AS1 served as a competing endogenous RNA to upregulate SIRT1 by sponging miR-135a-5p. In addition, SIRT1 silencing also restrained cell proliferation and motility. Rescue assays revealed the biological function of FOXD3-AS1/miR-135a-5p/SIRT1 axis in CRC progression. In conclusion, FOXD3-AS1 promotes CRC progression by regulating miR-135a-5p/SIRT1 axis, shedding lights on the way to CRC treatments.  相似文献   
76.
Accumulating studies have implicated that microRNAs (miRNAs) are involved in the pathogenesis of colorectal cancer (CRC). However, the role of miR-548c-5p, a novel identified miRNA in malignancies, in colorectal carcinogenesis remains largely unknown. The present study is aimed to investigate the effect and molecular mechanism of miR-548c-5p in CRC by a sequence of cellular experiments. miR-548c-5p was significantly downregulated, whereas phosphoglycerate kinase 1 (PGK1), a key enzyme for glycolysis, was obviously upregulated in peripheral blood mononuclear cells and cancer tissues from patients with CRC. Besides, miR-548c-5p and PGK1 were negatively associated with each other. The luciferase reporter assay revealed that PGK1 was a targeted gene of miR-548c-5p. Moreover, the proliferation and generation of inflammatory cytokines (TNF-α and IL-6) were significantly inhibited in miR-548c-5p-overexpressed SW480 CRC cells stimulated by lipopolysaccharide (LPS). Accordingly, miR-548c-5p may serve as a cancer suppressor in CRC by targeting PGK1.  相似文献   
77.
Zhao  Beiyu  Liu  Peng  Wei  Meng  Li  Yanbo  Liu  Jie  Ma  Louyan  Shang  Suhang  Jiang  Yu  Huo  Kang  Wang  Jin  Qu  Qiumin 《Neurochemical research》2019,44(4):859-873

Amyloid-β (Aβ) plays an important role in Alzheimer’s disease (AD) pathogenesis, and growing evidence has shown that poor sleep quality is one of the risk factors for AD, but the mechanisms of sleep deprivation leading to AD have still not been fully demonstrated. In the present study, we used wild-type (WT) rats to determine the effects of chronic sleep restriction (CSR) on Aβ accumulation. We found that CSR-21d rats had learning and memory functional decline in the Morris water maze (MWM) test. Meanwhile, Aβ42 deposition in the hippocampus and the prefrontal cortex was high after a 21-day sleep restriction. Moreover, compared with the control rats, CSR rats had increased expression of β-site APP-cleaving enzyme 1 (BACE1) and sAPPβ and decreased sAPPα levels in both the hippocampus and the prefrontal cortex, and the BACE1 level was positively correlated with the Aβ42 level. Additionally, in CSR-21d rats, low-density lipoprotein receptor-related protein 1 (LRP-1) levels were low, while receptor of advanced glycation end products (RAGE) levels were high in the hippocampus and the prefrontal cortex, and these transporters were significantly correlated with Aβ42 levels. In addition, CSR-21d rats had decreased plasma Aβ42 levels and soluble LRP1 (sLRP1) levels compared with the control rats. Altogether, this study demonstrated that 21 days of CSR could lead to brain Aβ accumulation in WT rats. The underlying mechanisms may be related to increased Aβ production via upregulation of the BACE1 pathway and disrupted Aβ clearance affecting brain and peripheral Aβ transport.

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78.
Laryngocarcinoma is the most common head and neck cancer and has a high incidence and mortality, causing about 83 000 deaths per year worldwide. Our research aimed to investigate the possible role of long noncoding RNA (lncRNA) taurine upregulated gene 1 (TUG1) in laryngocarcinoma development. The messenger RNA (mRNA) levels of TUG1 in tumor tissues and control (plasma) samples of laryngocarcinoma patients as well as in laryngocarcinoma cells were detected. The influences of TUG1 suppression on cell biological processes (viability, apoptosis, migration, and invasion) and cytoskeleton rearrangement in laryngocarcinoma cells were tested. Moreover, we investigated the regulatory interaction between TUG1 and miR-145-5p, and identified the target gene of miR-145-5p. The association between TUG1 and the protein expressions of RhoA/rho associated coiled-coil containing protein kinase (ROCK)/matrix metalloproteinases (MMPs) pathway-associated factors were detected. TUG1 was found to be highly expressed in tumor tissues and plasma samples of laryngocarcinoma patients as well as in laryngocarcinoma cells. Suppression of TUG1 decreased laryngocarcinoma cell viability, increased apoptosis, and suppression migration, invasion, and cytoskeleton rearrangement. Moreover, TUG1 negatively regulated miR-145-5p. TUG1 regulated tumor growth (viability and apoptosis) and metastasis through miR-145-5p. Furthermore, ROCK1 was targeted by miR-145-5p, and miR-145-5p/ROCK1 partner was involved in the process of tumor growth and metastasis. Finally, we found that TUG1 functioned on laryngocarcinoma by activating RhoA/ROCK/MMPs pathway. Our study reveals that lncRNA TUG1 is upregulated in laryngocarcinoma and may be involved in the process of laryngocarcinoma through miR-145-5p downregulation and activating the RhoA/ROCK/MMPs signals.  相似文献   
79.
Malignant glioma is a severe type of brain tumor with a grim prognosis. The occurrence of resistance compromises the efficacy of chemotherapy for glioma. Long noncoding RNA growth arrest-specific 5 (GAS5) has recently become an attractive target for cancer therapy by regulating cell growth, invasion, and migration. Nevertheless, its role in glioma chemoresistance remains elusive. In the current study, the expression of GAS5 was decreased in glioma cell lines, and lower levels of GAS5 were observed in U138 and LN18 glioma cells that had low sensitivity to cisplatin. Functional assay confirmed that knockdown of GAS5 enhanced cell resistance to cisplatin in U87 cells, which had a relatively high expression of GAS5. Conversely, elevation of GAS5 increased cell sensitivity to cisplatin in U138 cells that had a relatively low expression of GAS5. Mechanistically, cisplatin exposure evoked excessive autophagy concomitant with an increase in autophagy-related LC3II expression and a decrease in autophagy substrate p62 expression, which was reversely muted after GAS5 overexpression. In addition, GAS5 restored cisplatin-inhibited mammalian target of rapamycin (mTOR) activation. Preconditioning with mTOR antagonist rapamycin engendered not only mTOR inhibition but also abrogated GAS5-mediated depression in cisplatin-evoked autophagy. Notably, blocking the mTOR pathway also attenuated GAS5-increased sensitivity to cisplatin in U138 cells. Cumulatively, these findings indicate that GAS5 may blunt the resistance of glioma cells to cisplatin by suppressing excessive autophagy through the activation of mTOR signaling, implying a promising therapeutic strategy against chemoresistance in glioma.  相似文献   
80.
现有主流猕猴桃品种的遗传背景相对单一,亲本来源地理分布狭窄,亲缘关系不清晰。为充分利用杂种优势,该研究以广西植物研究所猕猴桃种质资源圃收集的53个猕猴桃品种(品系)叶片为材料,使用SCoT分子标记进行遗传多样性分析。结果表明:(1)10条引物在53份猕猴桃供试材料中共扩增出110条条带,各引物扩增的条带在8~15条之间,引物平均扩增条带数为11条;其中多态性条带101条,引物平均扩增多态性条带数为10.1条,多态性比例为91.81%。(2)聚类分析显示猕猴桃品种(品系)没有按类型、倍性或选育地等形成明显有规律的聚类关系。但相对来说,同一杂交后代个体之间的亲缘关系比亲本与后代个体之间的亲缘关系更近;芽变品种与原品种并没有表现出特别近的遗传距离,说明芽变材料的突变可能在基因组或染色体层面发生了较大范围的重组、复制或丢失;‘楚红’‘桂红’‘湘吉红’和‘龙藏红’4个红肉品种与‘红阳’亲缘关系明显较远,说明其可能由不同亲本衍生而来;初步验证了‘桂海四号’可能为‘Hort16A’亲本之一的推测。  相似文献   
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