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101.
102.
Jing Cui Kai Shan Qin Yang Yumin Qi Hongyan Qu Jiaqi Li Rong Wang Lingling Jia Wei Chen Ninghan Feng Yong Q. Chen 《Journal of cellular and molecular medicine》2021,25(12):5586-5601
Alternative polarization of macrophages regulates multiple biological processes. While M1-polarized macrophages generally mediate rapid immune responses, M2-polarized macrophages induce chronic and mild immune responses. In either case, polyunsaturated fatty acid (PUFA)-derived lipid mediators act as both products and regulators of macrophages. Prostaglandin E3 (PGE3) is an eicosanoid derived from eicosapentaenoic acid, which is converted by cyclooxygenase, followed by prostaglandin E synthase successively. We found that PGE3 played an anti-inflammatory role by inhibiting LPS and interferon-γ-induced M1 polarization and promoting interleukin-4-mediated M2 polarization (M2a). Further, we found that although PGE3 had no direct effect on the growth of prostate cancer cells in vitro, PGE3 could inhibit prostate cancer in vivo in a nude mouse model of neoplasia. Notably, we found that PGE3 significantly inhibited prostate cancer cell growth in a cancer cell-macrophage co-culture system. Experimental results showed that PGE3 inhibited the polarization of tumour-associated M2 macrophages (TAM), consequently producing indirect anti-tumour activity. Mechanistically, we identified that PGE3 regulated the expression and activation of protein kinase A, which is critical for macrophage polarization. In summary, this study indicates that PGE3 can selectively promote M2a polarization, while inhibiting M1 and TAM polarization, thus exerting an anti-inflammatory effect and anti-tumour effect in prostate cancer. 相似文献
103.
Xiu-Ping Zhang Qinjunjie Chen Qu Liu Yang Wang Fei Wang Zhi-Ming Zhao Guo-Dong Zhao Wan Yee Lau Yu-Zhen Gao Rong Liu 《Journal of cellular and molecular medicine》2021,25(12):5615-5627
Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with aggressive biological behaviour. Its rapid proliferation and tumour growth require reprogramming of glucose metabolism or the Warburg effect. However, the association between glycolysis-related genes with clinical features and prognosis of PDAC is still unknown. Here, we used the meta-analysis to correlate the hazard ratios (HR) of 106 glycolysis genes from MSigDB by the cox proportional hazards regression analysis in 6 clinical data sets of PDAC patients to form a training cohort, and a single group of PDAC patients from the TCGA, ICGC, Arrayexpress and GEO databases to form the validation cohort. Then, a glycolysis-related prognosis (GRP) score based on 29 glycolysis prognostic genes was established in 757 PDAC patients from the training composite cohort and validated in 267 ICGC-CA validation cohort (all P < .05). In addition, including PADC, the prognostic value was also confirmed in other 7 out of 30 pan-cancer cohorts. The GRP score was significantly related to specific metabolism pathways, immune genes and immune cells in the patients with PADC (all P < .05). Finally, by combining with immune cells, the GRP score also well-predicted the chemosensitivity of patients with PADC in the TCGA cohort (AUC = 0.709). In conclusion, this study developed a GRP score for patients with PDAC in predicting prognosis and chemosensitivity for PDAC. 相似文献
104.
Zhentao Yang Liang Zhang Hai Zhu Ke Zhou Hangxiang Wang Yuchen Wang Rong Su Danjing Guo Lin Zhou Xiao Xu Penghong Song Shusen Zheng Haiyang Xie 《Journal of cellular and molecular medicine》2021,25(7):3511-3523
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
105.
Senka Vidović Alena Tomšik Jelena Vladić Stela Jokić Krunoslav Aladić Kristian Pastor Igor Jerković 《化学与生物多样性》2021,18(4):e2100058
The aim of this study was to extract Allium ursinum L. for the first time by supercritical carbon dioxide (SC−CO2) as green sustainable method. The impact of temperature in the range from 40 to 60 °C and pressure between 150 and 400 bar on the quality of the obtained extracts and efficiency of the extraction was investigated. The highest extraction yield (3.43 %) was achieved by applying the extraction conditions of 400 bar and 60 °C. The analysis of the extracts was performed by gas chromatography and mass spectrometry (GC/MS). The most dominant sulfur-containing constituent of the extracts was allyl methyl trisulfide with the highest abundance at 350 bar and 50 °C. In addition, the presence of other pharmacologically potent sulfur compounds was recorded including S-methyl methanethiosulfinate, diallyl trisulfide, S-methyl methylthiosulfonate, and dimethyl trisulfide. Multivariate data analysis tool was utilized to investigate distributions of the identified compounds among the extracts obtained under various extraction conditions and yields. It was determined that the SC−CO2 extraction can by efficiently used for A. ursinum. 相似文献
106.
β-Carboline-Based pH Fluorescent Probe and Its Application for Monitoring Enzymatic Ester Hydrolysis
A novel pH-activatable fluorescent probe, 1-(propan-2-yl)-9H-pyrido[3,4-b]indole-3-carboxylic acid ( L-1 ), based on β-carboline derivatives, has been developed, which displays significant fluorescent response toward pH variation with high selectivity, good photo-stability and favorable pKa value. Moreover, L-1 can dynamically monitor the release of protons during ester hydrolysis reaction in consistent with enzymatic kinetics manner. 相似文献
107.
为揭示城镇化进程中生境破碎化对鸟类多样性及分布格局的影响, 本研究于2017-2019年每年的4-8月使用样线法对贵州花溪大学城26块破碎化林地(面积介于0.3-290.4 ha)中的鸟类群落进行了10次调查。共记录到鸟类78种, 隶属于11目37科。其中, 东洋界物种数占56.4%, 古北界物种数占32.1%, 广布种占11.5%; 有中国特有种1种。剔除高空飞行、非森林鸟类及偶然出现物种后, 不同斑块中的鸟类物种数介于12-55之间, 平均每个斑块有23.2 ± 10.5种。线性回归分析显示, 鸟类物种丰富度与林地斑块的面积有显著相关性, 斑块面积越小, 鸟类物种丰富度越低; 斑块隔离度对物种丰富度没有显著影响。基于物种多度分布矩阵的WNODF (weighted nestedness metric based on overlap and decreasing fill)嵌套分析显示, 不同斑块中鸟类群落呈现出反嵌套结构。小斑块中鸟类物种丰富度较低可能与植物丰富度较低、食物资源稀缺和繁育条件不足有关, 但短距离的隔离对鸟类迁入或扩散影响有限。环境过滤效应、种间竞争或优先效应可能导致不同斑块间存在较大的物种组成差异, 从而导致反嵌套格局。因此, 本研究建议在城市规划建设中应注重维持栖息地的完整性, 对不同面积大小的破碎化斑块都应加以保护。 相似文献
108.
Rong Xu Yu-Hui Chen Ju-Fei Xia Ting-Xiao Zeng Yong-He Li Jia-Ying Zhu 《Journal of Asia》2021,24(2):1-6
Nutrient metabolism is crucial for the survival of insects through the diapause. However, little is known about the metabolic mechanism of prolonged diapause. The sawfly, Cephalcia chuxiongica (Hymenoptera: Pamphiliidae), is a notorious defoliator of pine trees in southwest China. One of the distinguishing biological characteristics of this pest is the prolonged diapause of about 1.5 years. In this study, the body lipid, carbohydrate (total body sugar, glycogen, trehalose, and glucose), protein, and glycerol contents were measured in diapausing larvae of C. chuxiongica. The results showed that the changes of biochemical composition in C. chuxiongica are associated with the diapause initiation, maintenance, and termination phases. During the initiation phase, trehalose, glucose, and glycerol increased significantly, but glycogen decreased sharply. In general, the lipid, carbohydrate, and glycerol levels decreased gradually across the maintenance phase. At termination phase, the contents of glycogen and lipid persistently decreased, while an increase of trehalose, glucose, and glycerol contents were detected. The protein level was significantly higher at maintenance phase than at initiation and termination phases. It was also found that elevation of trehalose, glucose, and glycerol contents occurred in winter. These implies that the metabolites with altered levels in diapausing larvae of C. chuxiongica are responsible for maintaining a prolonged development and overwintering. 相似文献
109.
[目的]扩增西伯利亚蝗Gomphocerus sibiricus抗菌肽(attacin)基因,并对其进行生物信息学分析,同时分析西伯利亚蝗不同组织中抗菌肽基因的差异表达.[方法]基于RACE技术从西伯利亚蝗中克隆得到抗菌肽,利用生物信息学软件对西伯利亚蝗抗菌肽的一级结构、二级结构、三级结构、系统进化和亚细胞定位进行分析.采用实时荧光定量PCR技术检测了西伯利亚蝗抗菌肽基因在马氏管、中肠、后肠、脂肪体和唾液腺中的相对表达量.[结果]克隆获得的抗菌肽基因的开放阅读框为282 bp,编码93个氨基酸,其编码蛋白预测理论分子量为9.98 ku,等电点为9.26.抗菌肽氨基酸序列中存在信号肽序列.基因定量分析显示,抗菌肽基因在西伯利亚蝗的中肠中表达量最高.[结论]attacin在西伯利亚蝗成虫不同组织中差异表达,提示其消化道在防御病原微生物的入侵中起着重要的作用. 相似文献
110.
X.L. Hu K.Y. Tong X.J. Wei W. Rong E.A. Susanto S.K. Ho 《Journal of electromyography and kinesiology》2013,23(5):1065-1074
Loss of hand function and finger dexterity are main disabilities in the upper limb after stroke. An electromyography (EMG)-driven hand robot had been developed for post-stroke rehabilitation training. The effectiveness of the hand robot assisted whole upper limb training was investigated on persons with chronic stroke (n = 10) in this work. All subjects attended a 20-session training (3–5 times/week) by using the hand robot to practice object grasp/release and arm transportation tasks. Significant motor improvements were observed in the Fugl-Meyer hand/wrist and shoulder/elbow scores (p < 0.05), and also in the Action Research Arm Test and Wolf Motor Function Test (p < 0.05). Significant reduction in spasticity of the fingers as was measured by the Modified Ashworth Score (p < 0.05). The training improved the muscle co-ordination between the antagonist muscle pair (flexor digitorum (FD) and extensor digitorum (ED)), associated with a significant reduction in the ED EMG level (p < 0.05) and a significant decrease of ED and FD co-contraction during the training (p < 0.05); the excessive muscle activities in the biceps brachii were also reduced significantly after the training (p < 0.05). 相似文献