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991.
Zeyu Wu Tingting Wang Yonghong Song Yang Lu Tianyun Chen Pengpeng Chen 《Journal of liposome research》2019,29(2):133-141
The purpose of this study was to optimize the preparation conditions of podophyllotoxin liposomes (PPT-Lips), and to investigate their effects on PC3 cells. PPT-Lips were prepared by using a thin-film dispersion method. In order to achieve maximum drug encapsulation efficiency (EE), the process and formulation variables were optimized by response surface methodology (RSM). The optimum preparation conditions were cholesterol to lecithin ratio of 3.6:40 (w/w), lipid to drug ratio of 15.8:1 (w/w), and the ultrasonic intensity of 35% (total power of 400?W). The experimental EE of PPT-Lips was 90.425%, which was consistent with the theoretically predicted value. The characterization studies showed that PPT-Lips were well-dispersible spherical particles with an average size of 106?nm and a zeta potential of –10.1?mV. A gradual and time-dependent pattern of PPT from liposomes was found in in vitro drug release with a cumulative release amount up to 70.3% in 24?h. Results of cell viability experiments on PC3 cells demonstrated that PPT-Lips exhibited more effective anticancer activity in comparison with free PPT. Therefore, PPT-Lips represent an efficient and promising drug delivery system for PPT. 相似文献
992.
Xiafen Wu Lidan Ye Bingmei Su Zehui Shao 《Bioscience, biotechnology, and biochemistry》2019,83(7):1263-1269
As a chiral precursor for the important anticoagulant Edoxaban, enantioselective synthesis of (S)-3-cyclohexene-1-carboxylic acid is of great significance. The complicated procedures and generation of massive solid waste discourage its chemical synthesis, and the alternative biocatalysis route calls for an enzyme capable of asymmetric hydrolysis of racemic methyl-3-cyclohexene-1-carboxylate. To this end, we engineered the E. coli esterase BioH for improved S-enantioselectivity via rational design. By combinatorial modulation of steric and aromatic interactions, a positive mutant Mu3 (L24A/W81A/L209A) with relatively high S-selectivity in hydrolyzing racemic methyl-3-cyclohexene-1-carboxylate was obtained, improving the enantiomeric excess from 32.3% (the wild type) to 70.9%. Molecular dynamics simulation was conducted for both (R)- or (S)- complexes of the wild type and Mu3 to provide hints for the mechanism behind the increased S-selectivity. Moreover, the reaction conditions of Mu3 in methyl-3-cyclohexene-1-carboxylate hydrolysis was optimized to improve the conversion rate to 2 folds. 相似文献
993.
994.
Qinglian Wu Xian Bao Wanqian Guo Bing Wang Yunxi Li Haichao Luo Huazhe Wang Nanqi Ren 《Biotechnology advances》2019,37(5):599-615
Alternative chemicals to diverse fossil-fuel-based products is urgently needed to mitigate the adverse impacts of fossil fuel depletion on human development. To this end, researchers have focused on the production of biochemical from readily available and affordable waste biomass. This is consistent with current guidelines for sustainable development and provides great advantages related to economy and environment. The search for suitable biochemical products is in progress worldwide. Therefore, this review recommends a biochemical (i.e., medium chain carboxylic acids (MCCAs)) utilizing an emerging biotechnological production platform called the chain elongation (CE) process. This work covers comprehensive introduction of the CE mechanism, functional microbes, available feedstock types and corresponding utilization strategies, major methods to enhance the performance of MCCAs production, and the challenges that need to be addressed for practical application. This work is expected to provide a thorough understanding of the CE technology, to guide and inspire researchers to solve existing problems in depth, and motivate large-scale MCCAs production. 相似文献
995.
Yinfeng Yang Weiwei Zhou Yaorong Chen Qian Wu 《Journal of biomolecular structure & dynamics》2019,37(13):3467-3481
Adenosine is a ubiquitous endogenous nucleoside that controls numerous physiological functions via interacting with its specific G-coupled receptors. Activation of adenosine receptors (AdoRs), particularly A2B AdoRs promotes the release of inflammatory cytokines; reduces vascular permeabilization and induces angiogenesis, thereby making A2B AdoR becomes a potentially pharmacological target for drug development. Presently, for investigating the structural determinants of 164 xanthine derivatives as A2B AdoR antagonists, we performed an in silico study integrating with 3D-QSAR, docking and molecular dynamics (MD) simulation. The obtained optimal model shows strong predictability (Q2?=?0.647, R2ncv?=?0.955, and R2pred?=?0.848). Additionally, to explore the binding mode of the ligand with A2B AdoR and to understand their binding mechanism, docking analysis, MD simulations (20?ns), and the calculation of binding free energy were also carried out. Finally, the structural determinants of these xanthine derivatives were identified and a total of 20 novel A2B AdoR antagonists with improved potency were computationally designed, and their synthetic feasibility and selectivity were also evaluated. The information derived from the present study offers a better appreciation for exploring the interaction mechanism of the ligand with A2B AdoR, which could be helpful for designing novel potent A2B AdoR antagonists.
Communicated by Ramaswamy H. Sarma 相似文献
996.
Chun-Yang Wu Zhao-Feng Zhou Bin Wang Zun-Ping Ke Zhong-Chun Ge Xian-Jin Zhang 《Journal of cellular biochemistry》2019,120(2):1643-1650
Atherosclerosis has been recognized as a chronic inflammatory disease, which can harden the vessel wall and narrow the arteries. MicroRNAs exhibit crucial roles in various diseases including atherosclerosis. However, so far, the role of miR-328 in atherosclerosis remains barely explored. Therefore, our study concentrated on the potential role of miR-328 in vascular endothelial cell injury during atherosclerosis. In our current study, we observed that oxidized low-density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cells (HUVECs) apoptosis and inhibited cell viability dose-dependently and time-dependently. In addition, indicated dosage of ox-LDL obviously triggered HUVECs inflammation and oxidative stress process. Then, it was found that miR-328 in HUVECs was reduced by ox-LDL. HUVECs apoptosis was greatly repressed and cell survival was significantly upregulated by overexpression of miR-328. Furthermore, mimics of miR-328 rescued cell inflammation and oxidative stress process induced by ox-LDL. Oppositely, inhibitors of miR-328 strongly promoted ox-LDL-induced endothelial cells injury in HUVECs. By using bioinformatics analysis, high-mobility group box-1 (HMGB1) was predicted as a downstream target of miR-328. HMGB1 has been reported to be involved in atherosclerosis development. The correlation between miR-328 and HMGB1 was validated in our current study. Taken these together, it was implied that miR-328 ameliorated ox-LDL-induced endothelial cells injury through targeting HMGB1 in atherosclerosis. 相似文献
997.
Xiao-Jun Chen Wen-Jun Wu Qi Zhou Jin-Ping Jie Xiong Chen Fang Wang Xiao-Hua Gong 《Journal of cellular biochemistry》2019,120(2):2159-2170
Despite the administration of exogenous insulin and other medications used to control many aspects of diabetes mellitus (DM), increased oxidative stress has been increasingly acknowledged in DM development and complications. Therefore, this study aims to investigate the role of advanced glycation end-products (AGEs) in oxidative stress (OS) of thyroid cells in patients with DM. Patients with DM with or without thyroid dysfunction (TD) were enrolled. Thyroid toxic damage was induced by adding AGE-modified bovine serum albumin (AGE-BSA) to normal human thyroid follicular epithelial cells. The cell viability, cell cycle, and cell apoptosis, as well as the content of reactive oxygen species (ROS), catalase (CAT), and malondialdehyde (MDA) in cells were measured. Thyroid hormones, T3, T4, FT3, and FT4 levels were measured by enzyme-linked immunosorbent assay. Receptor for advanced glycation end products (RAGE), sirtuin1 ( Sirt1), and NF-E2-related factor 2 ( Nrf2) expressions were detected, and the mitochondrial membrane potential was measured. We found increased AGEs in the serum of DM patients with TD. By increasing AGE-BSA concentration, cell viability; the thyroid hormones T3, T4, FT3, and FT4 levels; and mitochondrial membrane potential all significantly decreased. However, the increase in AGE-BSA concentration led to an increase in cell apoptosis, RAGE, and nuclear factor-κB expressions but produced the opposite effect on Sirt1, Nrf2, and heme oxygenase-1 expressions, as well as a decrease in antioxidant response element protein levels. The AGE-BSA increased ROS and MDA levels and reduced CAT level in normal human thyroid follicular epithelial cells on a dose independence basis. Our results demonstrated that AGEs-mediated direct increase of RAGE produced OS in thyroid cells of DM by inactivating the Sirt1/Nrf2 axis. 相似文献
998.
Xuegang Wang Tao Wang Chenxi Chen Zhun Wu Peide Bai Shouchun Li Bin Chen Rongfu Liu Kaiyan Zhang Wei Li Yuedong Chen Jinchun Xing 《Journal of cellular biochemistry》2019,120(2):1492-1502
Exosomal microRNAs (miRNAs) are suggested to reflect molecular changes occurring in their cells of origin and are potential indicators in the early detection of cancers. This study aimed to determine whether certain exosomal miRNAs from tumor tissue can be used as noninvasive biomarkers for clear cell renal cell carcinoma (ccRCC). Based on ccRCC miRNA expression profiles and the literature, we selected six miRNAs (miR-210, miR-224, miR-452, miR-155, miR-21, and miR-34a) and analyzed their expression in tissues, sera, and serum exosomes through quantitative real-time polymerase chain reaction in hypoxia-induced (with CoCl2) renal cell lines. miR-210, miR-224, miR-452, miR-155, and miR-21 were upregulated in tumor tissues compared with normal tissues. Serum miR-210 and miR-155 levels were higher in patients with ccRCC than in healthy controls (HCs). Furthermore, only exosomal miR-210 was significantly upregulated in patients with ccRCC than in HCs. Moreover, receiver operating characteristic (ROC) curve analysis revealed an area under the ROC curve of 0.8779 (95% confidence interval, 0.7987-0.9571) and a sensitivity and specificity of 82.5% and 80.0%, respectively. Moreover, exosomal miR-210 was upregulated at an advanced stage, and Fuhrman grade and metastasis decreased significantly one month after surgery. Acute hypoxia exposure activates miR-210 and release of exosomes with upregulated miR-210 in both normal and tumor RCC cell lines and interferes with vacuole membrane protein 1 mRNA expression, especially in the metastatic ccRCC cell line. In conclusion, Serum exosomal miR-210 originating from tumor tissue has potential as a novel noninvasive biomarker for the detection and prognosis of ccRCC. 相似文献
999.
Yongcun Liu Junli Li Feng Li Meng Li Yuan Shao Liping Wu 《Journal of cellular biochemistry》2019,120(4):6120-6126
Small nucleolar RNA host gene 15 (SNHG15) has been suggested to be overexpressed, and function as an oncogenic long noncoding RNA (lncRNA) in various types of human malignancies. However, the expression status and function of SNHG15 were still unknown in thyroid cancer. In our study, we assessed the expression status and clinical value in thyroid cancer samples, and explored the effect of SNHG15 on thyroid cancer cell proliferation, migration, and invasion. In results, SNHG15 expression was downregulated in thyroid cancer tissues and cells, and correlated with age, pathology classification, clinical stage, tumor size, distant metastasis, and disease-free survival. The in vitro studies suggested SNHG15 overexpression suppressed cell proliferation, migration, and invasion in thyroid cancer. In summary, SNHG15 serves as tumor suppressive role in thyroid cancer. 相似文献