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951.
952.
Hepatocellular carcinoma (HCC) is one of the most aggressive tumours with marked fibrosis. Mycophenolate mofetil (MMF) was well-established to have antitumour and anti-fibrotic properties. To overcome the poor bioavailability of MMF, this study constructed two MMF nanosystems, MMF-LA@DSPE-PEG and MMF-LA@PEG-PLA, by covalently conjugating linoleic acid (LA) to MMF and then loading the conjugate into polymer materials, PEG5k-PLA8k and DSPE- PEG2k, respectively. Hepatocellular carcinoma cell lines and C57BL/6 xenograft model were used to examine the anti-HCC efficacy of nanoparticles (NPs), whereas NIH-3T3 fibroblasts and highly-fibrotic HCC models were used to explore the anti-fibrotic efficacy. Administration of NPs dramatically inhibited the proliferation of HCC cells and fibroblasts in vitro. Animal experiments revealed that MMF-LA@DSPE-PEG achieved significantly higher anti-HCC efficacy than free MMF and MMF-LA@PEG-PLA both in C57BL/6 HCC model and highly-fibrotic HCC models. Immunohistochemistry further confirmed that MMF-LA@DSPE-PEG dramatically reduced cancer-associated fibroblast (CAF) density in tumours, as the expression levels of alpha-smooth muscle actin (α-SMA), fibroblast activation protein (FAP) and collagen IV were significantly downregulated. In addition, we found the presence of CAF strongly correlated with increased HCC recurrence risk after liver transplantation. MMF-LA@DSPE-PEG might act as a rational therapeutic strategy in treating HCC and preventing post-transplant HCC recurrence.  相似文献   
953.
Androgen receptor (AR) and its variants play vital roles in development and progression of prostate cancer. To clarify the mechanisms involved in the enhancement of their actions would be crucial for understanding the process in prostate cancer and castration-resistant prostate cancer transformation. Here, we provided the evidence to show that pre-mRNA processing factor 6 (PRPF6) acts as a key regulator for action of both AR full length (AR-FL) and AR variant 7 (AR-V7), thereby participating in the enhancement of AR-FL and AR-V7-induced transactivation in prostate cancer. In addition, PRPF6 is recruited to cis-regulatory elements in AR target genes and associates with JMJD1A to enhance AR-induced transactivation. PRPF6 also promotes expression of AR-FL and AR-V7. Moreover, PRPF6 depletion reduces tumor growth in prostate cancer-derived cell lines and results in significant suppression of xenograft tumors even under castration condition in mouse model. Furthermore, PRPF6 is obviously highly expressed in human prostate cancer samples. Collectively, our results suggest PRPF6 is involved in enhancement of oncogenic AR signaling, which support a previously unknown role of PRPF6 during progression of prostate cancer and castration-resistant prostate cancers.  相似文献   
954.
Prostate cancer (PC) is the most common carcinoma among men worldwide which results in 26% of leading causes of cancer-related death. However, the ideal and effective molecular marker remains elusive. CircRNA, initially observed in plant-infected viruses and Sendai virus in 1979, is generated from pre-mRNA back-splicing and comes in to play by adequate expression. The differential expression in prostate tissues compared with the control reveals the promising capacity in modulating processes including carcinogenesis and metastasis. However, the biological mechanisms of regulatory network in PC needs to systemically concluded. In this review, we enlightened the comprehensive studies on the definite mechanisms of circRNAs affecting tumor progression and metastasis. What''s more, we validated the potential clinical application of circRNAs serving as diagnostic and prognostic biomarker. The discussion and analysis in circRNAs will broaden our knowledge of the pathogenesis of PC and further optimize the current therapies against different condition.  相似文献   
955.
Lake Taihu in China has suffered serious harmful cyanobacterial blooms for decades. The algal blooms threaten the ecological sustainability, drinking water safety, and human health. Although the roles of abiotic factors (such as water temperature and nutrient loading) in promoting Microcystis blooms have been well studied, the importance of biotic factors (e.g. bacterial community) in promoting and meditating Microcystis blooms remains unclear. In this study, we investigated the ecological dynamics of bacterial community, the ratio of toxic Microcystis, as well as microcystin in Lake Taihu. High-throughput 16S rRNA sequencing and principal component analysis (PCA) revealed that the bacteria community compositions (BCCs) clustered into three groups, the partitioning of which corresponded to that of groups according to the toxic profiles (the ratio of toxic Microcystis to total Microcystis, and the microcystin concentrations) of the samples. Further Spearman's correlation network showed that the α-proteobacteria Phenylobacterium strongly positively correlated with the toxic profiles. Subsequent laboratory chemostats experiments demonstrated that three Phenylobacterium strains promoted the dominance of the toxic Microcystis aeruginosa PCC7806 when co-culturing with the non-toxic PCC7806 mcyB mutant. Taken together, our data suggested that the α-proteobacteria Phenylobacterium may play a vital role in the maintenance of toxic Microcystis dominance in Lake Taihu.  相似文献   
956.
Liu  Yue  Sun  Jiandong  Su  Yang  Lin  Jianmin  Lv  Chengyu  Mo  Kaien  Xu  Songhua  Wang  Shie 《Journal of molecular histology》2021,52(5):965-973
Journal of Molecular Histology - Preimplantation embryo development is characterized by drastic nuclear reprogramming and dynamic stage-specific gene expression. Key regulators of this earliest...  相似文献   
957.
Biomechanics and Modeling in Mechanobiology - The human lumbar facet capsule, with the facet capsular ligament (FCL) that forms its primary constituent, is a common source of lower back pain. Prior...  相似文献   
958.
Li  Zhenzi  Liu  Pan  Yuan  Yanan  Liang  Xiaoxiao  Lei  Jun  Zhu  Xiaobin  Zhang  Zuoqi  Cai  Lin 《Biomechanics and modeling in mechanobiology》2021,20(5):2013-2030
Biomechanics and Modeling in Mechanobiology - Osteoporosis (OP), a skeletal disease making bone mechanically deteriorate and easily fracture, is a global public health issue due to its high...  相似文献   
959.
中国建立国家公园的目的是保护自然生态系统的完整性和原真性, 促进生物多样性保护。国家公园的完整性和原真性评价是国家公园的布局规划、边界范围确定以及功能区划等研究的前提条件。为了评估国家公园自然生态系统完整性和原真性状态, 本文基于陆地自然生态系统的结构和功能, 通过指标筛选、专家咨询、指标量化和建立综合评价模型, 构建了陆地自然生态系统完整性与原真性的评价指标体系及其量化评价方法。该评价方法包括5个自然生态系统完整性指标、5个自然生态系统原真性指标和2个综合评价指标。以浙江省钱江源国家公园体制试点为例, 本文初步评估了其生态系统完整性与原真性状态, 并对评价结果进行了分级。按照本研究的评价方法, 钱江源国家公园体制试点的自然生态系统完整性评价结果为52.83%, 评价等级为较差; 自然生态系统原真性评价结果为87.06%, 评价等级为好。钱江源国家公园体制试点有待关注和提升的指标有保护区域完整性指数(27.00%)和旗舰种适宜生境完整性指数(53.04%)。最后, 本文结合研究区域评价结果对生态系统完整性和原真性领域应关注的问题进行了讨论。该自然生态系统完整性和原真性评价方法可提供一种评价指标覆盖较全面、数据易获取, 且评价结果易被决策者和管理者理解的评价思路。  相似文献   
960.
隆水蚤科以其丰富的个体数和多样性成为海洋水体生态系统中极为重要的小型桡足类, 但其分类学和多样性研究仍有较大不足, 其生态功能及在生态系统中的地位存在被低估的可能。为了提升对隆水蚤科的认识, 本文对国际隆水蚤科分类学和物种多样性研究进展、隆水蚤科的物种多样性研究难点和技术发展趋势、隆水蚤科的分布和生态等方面研究进行概述。19世纪末Giesbrecht创建隆水蚤科, 随后该科的新物种不断被发现和描述, 目前已描述115种。中国海仅记录到隆水蚤科物种11种, 相关生态学研究较薄弱。隆水蚤科由于个体小, 许多物种间具有高度的形态相似性, 并且包含很多姐妹种及种内分型, 因此许多研究将传统分类鉴定手段与分子生物学技术相结合, 以提高物种的发现和描述效率。随着研究的不断深入, 有关隆水蚤科物种的分布特征、食性特征、种群特征和行为学特征等均得到不同程度的关注, 这都将提高隆水蚤科研究的广度和深度。随着研究技术的迅速发展以及许多设备先进的科学考察船和载人潜水器被用于海洋研究, 从近海、边缘海到深远海研究的协同发展, 海洋生物样品资源不断丰富, 这将带动我国分类和多样性研究快速发展, 使隆水蚤科的分类学研究不断深入。  相似文献   
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