Paclitaxel inhibits proliferation and promotes apoptosis through regulation ROS and endoplasmic reticulum stress in osteosarcoma cell

Li Ming,Yin Liming,Wu Lili,Zhu Yunsen,Wang Xi 대한독성 유전단백체 학회 2020 Molecular & cellular toxicology Vol.16 No.4

Background Paclitaxel is a chemotherapeutic drug for cancer, which is isolated from the Pacifc yew tree. However, and the molecular mechanism and the antitumor efects of paclitaxel on osteosarcoma cell remain to be explored. Objective The aim of our study was to explore the possible molecular mechanisms of apoptosis in osteosarcoma induced by paclitaxel. Results Paclitaxel can obviously decrease the proliferation of HOS-732 cells in a dose-dependent manner. Paclitaxel could induce the cell cycle arrest at the G2/M-phase and decreases the CDK5 and CCNE1 expression in HOS-732 cells. Paclitaxel promotes cell apoptosis in HOS-732 cells, which may be contacted to the decreasing of Bcl-2 protein expression. Further, the production of ROS in HOS-732 cells was remarkably increased with the increasing concentration of paclitaxel. Moreover, paclitaxel induces the ER-stress related gene and protein expression (GRP79, DDIT3 mRNA and GRP78, XBP-1 s, IRE1α protein expression) in osteosarcoma cells. Conclusion Paclitaxel can inhibit the proliferation of HOS-732 cells and increase ROS and ER-stress response to promote cell apoptosis, suggesting that paclitaxel may represent a new therapeutic option for the treatment and prevention osteosarcoma.

Design and Construction of Polyaniline/Reduced Graphene Oxide Three-Dimensional Dendritic Architecture on Interdigital Electrode for Sensitive Detection Nitrite

Li Li,Huan Liu,Boya Li,Yanan Guo,Liming Qing,Baohui Wang 한국고분자학회 2020 Macromolecular Research Vol.28 No.5

The polyaniline/reduced graphene oxide (PANI/RGO) modified interdigital electrode (IDE) has been successfully fabricated by in situ electrochemical reduction and electrochemical polymerization through cyclic voltammetry. The morphology and topography of PANI/RGO characterized by SEM and AFM display intercrosslinked dendritic structure in three dimensions, and it is favorable for the detection of nitrite due to its large surface area, which can provide the large electrocatalytic active surface and various diffusion paths for nitrite. Herein, the obtained PANI/ RGO/IDE was employed for the electrochemical monitoring platform of nitrite for the first time and the electrochemical performance of the as-developed sensor was investigated via cyclic voltammetry and chronoamperometry. At the optimum conditions, the PANI/RGO/IDE has a linear response in the range from 0.4 to 183.7 mM with a sensitivity of 457.4 μA mM-1 cm-2 and a detection limit of 0.1 μM. Moreover, the obtained PANI/RGO/IDE with excellent long-term stability and reproducibility also can be employed for practical application for the determination of nitrite in tap water, the results show that the recovery rate is desirable. It is expected that IDE can be employed as the substrate electrode decorated with various materials to construct highperformance electrochemical sensors.

Histone demethylase KDM4A plays an oncogenic role in nasopharyngeal carcinoma by promoting cell migration and invasion

Zhao Jingyi,Li Bingyan,Ren Yongxia,Liang Tiansong,Wang Juan,Zhai Suna,Zhang Xiqian,Zhou Pengcheng,Zhang Xiangxian,Pan Yuanyuan,Gao Fangfang,Zhang Sulan,Li Liming,Yang Yongqiang,Deng Xiaoyu,Li Xiaole,C 생화학분자생물학회 2021 Experimental and molecular medicine Vol.53 No.-

Compelling evidence has indicated the vital role of lysine-specific demethylase 4 A (KDM4A), hypoxia-inducible factor-1α (HIF1α) and the mechanistic target of rapamycin (mTOR) signaling pathway in nasopharyngeal carcinoma (NPC). Therefore, we aimed to investigate whether KDM4A affects NPC progression by regulating the HIF1α/DDIT4/mTOR signaling pathway. First, NPC and adjacent tissue samples were collected, and KDM4A protein expression was examined by immunohistochemistry. Then, the interactions among KDM4A, HIF1α and DDIT4 were assessed. Gain- and loss-of-function approaches were used to alter KDM4A, HIF1α and DDIT4 expression in NPC cells. The mechanism of KDM4A in NPC was evaluated both in vivo and in vitro via RT-qPCR, Western blot analysis, MTT assay, Transwell assay, flow cytometry and tumor formation experiments. KDM4A, HIF1α, and DDIT4 were highly expressed in NPC tissues and cells. Mechanistically, KDM4A inhibited the enrichment of histone H3 lysine 9 trimethylation (H3K9me3) in the HIF1α promoter region and thus inhibited the methylation of HIF1α to promote HIF1α expression, thus upregulating DDIT4 and activating the mTOR signaling pathway. Overexpression of KDM4A, HIF1α, or DDIT4 or activation of the mTOR signaling pathway promoted SUNE1 cell proliferation, migration, and invasion but inhibited apoptosis. KDM4A silencing blocked the mTOR signaling pathway by inhibiting the HIF1α/DDIT4 axis to inhibit the growth of SUNE1 cells in vivo. Collectively, KDM4A silencing could inhibit NPC progression by blocking the activation of the HIF1α/DDIT4/mTOR signaling pathway by increasing H3K9me3, highlighting a promising therapeutic target for NPC.

A Novel Vibration Model for Explanation of the Frequency Features in Multistage Wind Turbine Gearboxes Considering the Effects of Inter-stage Meshing Frequency Modulation

Yanyan Nie,Fangyi Li,Liming Wang,Jianfeng Li,Yanle Li,Mingshuai Sun,Mengyao Wang,Guoyan Li 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.1

As a kind of green energy, wind energy has become cost-competitive mainstream energy in the world. The gearbox is one of the most important and vulnerable components in the wind turbine (WT), which suffers a high failure rate and downtime. It is of great significance to the condition monitoring and fault diagnosis of the WT gearbox. However, in the multistage WT gearbox, the vibrations generated from different stages are coupled, which leads to a complex vibration spectral structure and brings difficulties in condition monitoring and fault diagnosis. Aiming to understand the vibration frequency features of multistage WT gearboxes, a novel phenomenological vibration model is established and the spectral structure is deduced by using the Fourier series analysis. In the vibration model, the phenomenon of inter-stage meshing frequency modulation (ISMFM) is considered, which is clearly proposed for the first time. The theoretical derivations are validated by both simulation and engineering tests using a 2.0 MW industrial WT gearbox. The results show that under healthy conditions, in addition to the meshing frequencies and their harmonics of each stage, there are also ISMFM sidebands in the vibration spectrum of the multistage WT gearbox, and the amplitude of the sidebands will change with the health status of the gearbox. The findings are not only applicable to the WT gearbox studied in this paper, but also to other similar multistage gearbox systems, which can provide a priori spectral structure for a multistage gear transmission system to assist its condition monitoring and fault diagnosis.

Testicular Characteristics and the Block to Spermatogenesis in Mature Hinny

Han, Hongmei,Wang, Aihong,Liu, Liming,Zhao, Gaoping,Su, Jie,Wang, Biao,Li, Yunxia,Zhang, Jindun,Wu, Baojiang,Sun, Wei,Hu, Shuxiang,Li, Shuyu,Zhao, Lixia,Li, Xihe Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.6

Most hinnies (female donkey${\times}$male horse) and mules (female horse${\times}$male donkey) are sterile with few reports of equine fertile hybrids. The main cause of this sterility is thought to be a meiotic block to spermatogenesis and oogenesis. This study compared the developmental features of the testes and a histological analyses of spermatogenesis in a male hinny with those of a normal, fertile stallion and Jack donkey. Hinny testes showed a thicker tunica albuginea, fewer blood vessels and more connective tissue in the testis parenchyma than those of the stallion and Jack donkey. Although the mean number of seminiferous tubules was significantly higher in stallion and hinny than Jack donkey (p<0.01), the mean proportion of seminiferous tubules was lower in the hinny (p<0.01) which resulted in a smaller diameter of seminiferous tubules. The mean number of spermatogonia and spermatocytes per unit area were significantly lower in hinny testis (p<0.01) and no spermatids or mature spermatozoa cells were found during immunofluorescent analyses. These results indicated that defects in seminiferous tubule development and structure occur in the testis of hinnies. Furthermore, most spermatogonia and spermatocytes cease development in synapsis during mid-meiosis of spermatocytes, which results in a block to spermatogenesis that prevents the formation of spermatids and matured spermatozoa during meiosis in male hinnies.

Aerodynamic performance analysis of partial admission dual row control stage at different working conditions

Liming Song,Jun Li,Kesong Wen 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.1

Aerodynamic performance of partial admission dual row control stage at the rated and off-designed operating conditions was numericallyinvestigated using three-dimensional Reynolds-averaged Navier-Stokes (RANS) and k -e turbulence model. The full scale computationalmodel includes the four nozzle boxes, full first and second row rotor blade, as well as two admission guided vanes with considerationof the rotor tip clearance and stator diaphragm gland. The numerical results of the mass flow rate, power output and aerodynamicefficiency of the dual row control stage at the rated and off-designed conditions are well in agreement with the experimental data. The obtained results at rated condition show that the blocking segmental arc of guided vane increased the exit pressure of the upstreamnozzle, which reduced the mass flow rate and changed the aerodynamic performance of the nozzle. The circumferential non-uniformityof aerodynamic parameters and partial admission losses increases with the decrease in the admission degree for the computed three operatingconditions. The analysis of axial steam velocity shows that the trailing shedding vortex and the complex flow vortex in flow passageshave a significant impact on the magnitude and direction of the axial steam velocity. Furthermore, the partial admission degreechanged the proportions of the power output of two rotor blade rows. The lower partial admission degree leads to a larger proportion ofthe power output of the first rotating blade row. The detailed flow pattern in the partial admissions dual row control stage at differentoperating conditions is also illustrated.

Noun Phrase Complexity in EFL Academic Writing : A Corpus-based Study of Postgraduate Academic Writing

Liming Liu,Lan Li 아시아영어교육학회 2016 The Journal of Asia TEFL Vol.13 No.1

Noun phrase (NP) centered structures are distinctive syntactic devices in academic discourse. The commonly employed subordination-based complexity measures cannot adequately capture the development of syntactic complexity of noun phrases expected of advanced student academic writing (Biber, Gray, & Poonpon, 2011). Following the call for more research in this area (e.g. Lu, 2011, p. 57), the current study compared noun phrase complexity in two corpora: one is a corpus of MA dissertations written by Chinese EFL students and the other comprises published research articles in applied linguistics journals. The study examined overall noun phrase complexity using an automatic syntactic complexity analyzer and specifically identified features of one aspect of NP complexity: NP postmodification. The quantitative results were further contextualized in a textual analysis of excerpts from the two corpora for demonstrating the significance of NP complexity to the establishment of discourse coherence. Results of the analyses showed significant underdevelopment of NP postmodification complexity in student writing relative to published texts, meanwhile explicating the circumstances under which the difference is meaningful. Implications of the findings for the teaching of EFL academic writing were also discussed.

A Parametric and Accurate CAD Model of Flat End Mills Based on Its Grinding Operations

Liming Wang,Lin Kong,Jian-Feng Li,Zezhong Chen 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.10

End mills are widely used in CNC machining. However, the complex structures of end mills make it difficult to define the CAD model which determines the quality and performance of virtual cutting tests. This paper presents an accurate CAD model of end mill through analyzing kinematic models of grinding processes. Initially, a common parametric representation of grinding wheel is given. Base on the given wheel profile and the design parameters of cutters including the rake angle, core diameters and pitch angle, the representation of helix flute surface is first calculated using contact theory and also the formulation of rake angle and pitch angle are investigated. Next, four design parameters are used to control the shape of the gash which is formed via Boolean operation between the given wheel and end mill. Similarly, the peripheral edges and end edges are swept using grinding simulation. Finally, integrating all the above processes, a parametric CAD model of end mill is represented. The simulation results showed that the proposed CAD model could achieve 1e-3 mm and 2e-2 deg. in accuracy, which can be used to evaluate the grinding process or improve the future FEA analysis of end-mills.

Polymorphisms of Inflammatory Cytokine Genes and Risk for Intracranial Aneurysm: A Systematic Review and Meta-Analysis

Liming Hu,Bingyang Li,Xin Liao,Junxia Yan 연세대학교의과대학 2020 Yonsei medical journal Vol.61 No.5

Purpose: Inflammatory cytokines are thought to be involved in the pathogenesis of intracranial aneurysm (IA), although results among studies in the literature are inconsistent. This article sought to review studies on the associations among polymorphisms in inflammatory cytokine genes and IA risk and to provide recommendations for future research. Materials and Methods: A systematic search of PubMed, Embase, and Web of Science was conducted up to August 4, 2019. The associations between polymorphisms of inflammatory cytokine genes and IA risk were estimated by pooled odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses were performed according to race. Qualitative systematic review was conducted for variants that were studied in only one study. All analyses were performed using STATA 12.0. Results: 13 studies investigating the associations between polymorphisms in five inflammatory cytokine genes (TNF-α, IL-1α, IL-1β, IL6, and IL-12B) and IA were reviewed. Combined results showed that the A allele of TNF-α rs1800629 polymorphism has a protective effect against IA (dominant model: OR=0.65, 95% CI=0.47–0.89, p=0.007). No associations were identified between polymorphisms in IL-1α rs1800587, IL-1β rs16944, IL6 rs1800795 and rs1800796, or IL-12B rs3212227 and IA risk. Conclusion: This review demonstrated an association between TNF-α rs1800629 polymorphism and IA in Caucasians, illustrating the potentially important role of genes involved in inflammation in IA.

Model test and numerical simulation on the bearing mechanism of tunnel-type anchorage

Li, Yujie,Luo, Rong,Zhang, Qihua,Xiao, Guoqiang,Zhou, Liming,Zhang, Yuting Techno-Press 2017 Geomechanics & engineering Vol.12 No.1

The bearing mechanism of tunnel-type anchorage (TTA) for suspension bridges is studied. Model tests are conducted using different shapes of plug bodies, which are circular column shape and circular truncated cone shape. The results show that the plug body of the latter shape possesses much larger bearing capacity, namely 4.48 times at elastic deformation stage and 4.54 times at failure stage compared to the former shape. Numerical simulation is then conducted to understand the mechanical and structural responses of plug body and surrounding rock mass. The mechanical parameters of the surrounding rock mass are firstly back-analyzed based on the monitoring data. The calculation laws of deformation and equivalent plastic strain show that the numerical simulation results are rational and provide subsequent mechanism analysis with an established basis. Afterwards, the bearing mechanism of TTA is studied. It is concluded that the plug body of circular truncated cone shape is able to take advantage of the material strength of the surrounding rock mass, which greatly enhances its bearing capacity. The ultimate bearing capacity of TTA, therefore, is concluded to be determined by the material strength of surrounding rock mass. Finally, recommendations for TTA design are proposed and discussed.