Dexmedetomidine promotes the progression of hepatocellular carcinoma through hepatic stellate cell activation

Chen Peng,Luo Xiaojun,Dai Guanqi,Jiang Yuchuan,Luo Yue,Peng Shuang,Wang Hao,Xie Penghui,Qu Chen,Lin Wenyu,Hong Jian,Ning Xue,Li Aimin 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

Dexmedetomidine (DEX) is an anesthetic that is widely used in the clinic, and it has been reported to exhibit paradoxical effects in the progression of multiple solid tumors. In this study, we sought to explore the mechanism by which DEX regulates hepatocellular carcinoma (HCC) progression underlying liver fibrosis. We determined the effects of DEX on tumor progression in an orthotopic HCC mouse model of fibrotic liver. A coculture system and a subcutaneous xenograft model involving coimplantation of mouse hepatoma cells (H22) and primary activated hepatic stellate cells (aHSCs) were used to study the effects of DEX on HCC progression. We found that in the preclinical mouse model of liver fibrosis, DEX treatment significantly shortened median survival time and promoted tumor growth, intrahepatic metastasis and pulmonary metastasis. The DEX receptor (ADRA2A) was mainly expressed in aHSCs but was barely detected in HCC cells. DEX dramatically reinforced HCC malignant behaviors in the presence of aHSCs in both the coculture system and the coimplantation mouse model, but DEX alone exerted no significant effects on the malignancy of HCC. Mechanistically, DEX induced IL-6 secretion from aHSCs and promoted HCC progression via STAT3 activation. Our findings provide evidence that the clinical application of DEX may cause undesirable side effects in HCC patients with liver fibrosis.

The current situation of the levonorgestrel intrauterine system (LNG-IUS) in conservative treatment for patients with early-stage endometrial cancer and atypical hyperplasia

Xiaojun Chen 대한부인종양학회 2019 Journal of Gynecologic Oncology Vol.30 No.4

A Methodology for Task placement and Scheduling Based on Virtual Machines

( Xiaojun Chen ),( Jing Zhang ),( Junhuai Li ) 한국인터넷정보학회 2011 KSII Transactions on Internet and Information Syst Vol.5 No.9

Task placement and scheduling are traditionally studied in following aspects: resource utilization, application throughput, application execution latency and starvation, and recently, the studies are more on application scalability and application performance. A methodology for task placement and scheduling centered on tasks based on virtual machines is studied in this paper to improve the performances of systems and dynamic adaptability in applications development and deployment oriented parallel computing. For parallel applications with no real-time constraints, we describe a thought of feature model and make a formal description for four layers of task placement and scheduling. To place the tasks to different layers of virtual computing systems, we take the performances of four layers as the goal function in the model of task placement and scheduling. Furthermore, we take the personal preference, the application scalability for a designer in his (her) development and deployment, as the constraint of this model. The workflow of task placement and scheduling based on virtual machines has been discussed. Then, an algorithm TPVM is designed to work out the optimal scheme of the model, and an algorithm TEVM completes the execution of tasks in four layers. The experiments have been performed to validate the effectiveness of time estimated method and the feasibility and rationality of algorithms. It is seen from the experiments that our algorithms are better than other four algorithms in performance. The results show that the methodology presented in this paper has guiding significance to improve the efficiency of virtual computing systems.

The Research on the Distribution Network Reconfiguration and the Application of Immune Particle Swarm Optimization

Zucheng Huang,Lixia Chen,Wei Chen,Xiaojun Chen 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.11

With the rapid development of national economy, the demand for electricity is more intense. There is a new demand for the security, reliability and applicability of the power distribution system. The power distribution system is an important component of power systems. It plays an important role in connecting power production and users. Now the most important problem is nonlinear combinatorial optimization in large-scale mixed lines and how to reconfigure the distribution network. However, by deeply analyzing and studying immune particle swarm optimization, the mathematical model of distribution network reconfiguration is established. By coding the characteristics of closed-loop design and open-loop operation, it aims to reduce the consumption of network, balance the grid load, eliminate the current overload and achieve the ultimate goal of improving the power supply reliability.

Biosensors and chemosensors based on the optical responses of polydiacetylenes

Chen, Xiaoqiang,Zhou, Guodong,Peng, Xiaojun,Yoon, Juyoung The Royal Society of Chemistry 2012 Chemical Society reviews Vol.41 No.13

<P>Polydiacetylenes (PDAs), a family of conjugated polymers, have very unique electrical and optical properties. Upon environmental stimulation, such as by viruses, proteins, DNAs, metal ions, organic molecules <I>etc</I>., the blue PDAs can undergo a colorimetric transition from blue to red, which is accompanied by a fluorescence enhancement. Since the first report on polymerized diacetylene molecules as sensors of influenza virus, the development of efficient sensory systems based on PDAs continues to be of great interest. This <I>tutorial review</I> highlights the recent advances in bio- and chemo-sensors derived from polydiacetylenes.</P> <P>Graphic Abstract</P><P>In this review, the recent advances in the development of chemical and biological sensors based on the polydiacetylene platform are highlighted. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cs35055f'> </P>

One-step synthesis of methylmethacrylate from methacrolein over Keggin-type heteropoly compounds

Xiaojun Guo,Chongpin Huang,Biaohua Chen 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.4

One-step synthesis of methylmethacrylate (MMA) using heteropoly compounds (HPCs) as catalysts was demonstrated by feeding a mixture of methacrolein (MAL), air, water, nitrogen and MeOH (methanol). The HPCs with different counter-ions, such as H1.7Cs1.5Cu0.25As0.1PMo11VO40 (CsPMo11VO40), H1.7La0.7Cu0.25As0.1PMo11VO40 (LaPMo11VO40) and H1.7K1.5Cu0.25As0.1PMo11VO40 (KPMo11VO40), were studied in oxidation of MAL, esterification of methacrylic acid (MAA) and one-step synthesis of MMA from MAL, respectively. The selectivity of MAA was up to 45.7% and MMA was 44.6% with 93.3% MAL conversion over CsPMo11VO40.

Molecular dynamics study of H4TTP crystal morphology

Chen Jing,Li Jun,Li Yongxiang,Liu Qiao'e,Zhang Xuan,Ruan Jian,Wang Xiaojun,Liu Wendong,Kim Chan Kyung 대한화학회 2022 Bulletin of the Korean Chemical Society Vol.43 No.7

To understand the role of dimethyl sulfoxide (DMSO) on the crystal growth morphology of 2,3,5,6-tetra(1H-tetrazol-5-yl)pyrazine (H4TTP), the vacuum morphology of H4TTP crystal was predicted by the Bravais–Friedel–Donnay–Harker (BFDH) and the attachment energy (AE) models. The growth morphology of H4TTP in DMSO solvent was predicted using a modified AE model. The results show that the main growth surfaces of H4TTP in vacuum are (1 0 0), (0 0 2), (0 1 1), and (1 1 0) surfaces. Among them, (1 0 0) surface is the most important growth surface. (0 0 2) surface is the roughest crystal surface, while (1 1 0) surface is the flattest. (1 1 0) surface grows rapidly, and (1 0 0) surface has the greatest morphological importance. The analysis of radial distribution function shows that (1 0 0) surface has the strongest hydrogen bonding interactions in the interface between H4TTP and DMSO solvent.

Calculation of cavitation evolution and associated turbulent kinetic energy transport around a NACA66 hydrofoil

Xiaojun Li,Bowen Li,Benxu Yu,Yun Ren,Bo Chen 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.3

The physical mechanism of flow unsteadiness is one of the key problems in cavitating flow. Significant efforts have been exerted to explain the cavitation-vortex interaction mechanism. As well, the process of kinetic energy transport during the evolution of unsteady cavitating flow must be elucidated. In this work, 2D calculations of cavitating flow around a NACA66 hydrofoil were performed based on the open source software OpenFOAM. The modified shear stress transport k-ω turbulence model, which considers curvature and turbulent eddy viscosity corrections, was employed to close the governing equations. The Schnerr-Sauer cavitation model was adopted to capture the cavitation phase change process. Numerical results showed reasonable consistency with the results of the experiments conducted by Leroux et al. (2004). The results showed that cavitation promotes turbulence intensity and flow unsteadiness around the hydrofoil. During the attached sheet cavity growth stage, high-value regions of turbulent kinetic energy are located substantially at the interface of the cavity, particularly at the rear portion of the cavity region. During the cloud cavity shed-off stage, the cavity begins to break off and the maximum value of turbulent kinetic energy is observed inside the shed cavity. Finally, the influence of cavitation on the turbulence intensity is illustrated using the turbulent kinetic energy transport equation, which shows that the pressure diffusion and turbulent transport terms dominate as cavitation occurs. In addition, cavitation promotes turbulence production and increases dissipation with fluid viscosity and flow unsteadiness. The viscous transport term only acts in the cavitation shedding stage under large-scale vortex shedding. Overall, these findings are of considerable interest in engineering applications.

Fluorescent and colorimetric probes for detection of thiols

Chen, Xiaoqiang,Zhou, Ying,Peng, Xiaojun,Yoon, Juyoung Royal Society of Chemistry 2010 Chemical Society reviews Vol.39 No.6

<P>Due to the biological importances of thiols, such as cysteine, homocysteine and glutathione, the development of optical probes for thiols has been an active research area in recent few years. This <I>critical review</I> focuses on the fluorescent or colorimetric sensors for thiols according to their unique mechanisms between sensors and thiols, including Michael addition, cyclization with aldehyde, cleavage of sulfonamide and sulfonate ester by thiols, cleavage of selenium–nitrogen bond by thiols, cleavage of disulfide by thiols, metal complexes-oxidation–reduction, metal complexes-displace coordination, nano-particles and others (110 references).</P> <P>Graphic Abstract</P><P>This review focuses on the fluorescent or colorimetric sensors for thiols according to their unique mechanisms between sensors and thiols. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b925092a'> </P>

GENERALIZED SCHWARZ LEMMAS FOR MEROMORPHIC FUNCTIONS

Xiaojun Huang,Ling Chen 대한수학회 2012 대한수학회보 Vol.49 No.2

In this paper, we prove an analog of the generalized Schwarz lemma for meromorphic functions. Our results improve the classical generalized Schwarz lemma.