Synthesis, Characterization and pH-Responsive Self-Assembly Behavior of Amphiphilic Multiarm Star Triblock Copolymers Based on PCL, PDEAEMA, and PEG

You Qiang Yang,Wen Jing Lin,Li Juan Zhang,Cheng Zhi Cai,Wei Jiang,Xin Dong Guo,Yu Qian 한국고분자학회 2013 Macromolecular Research Vol.21 No.9

A series of amphiphilic 4- and 6-armed star triblock copolymers based on poly(ε-caprolactone) (PCL),poly(2-(diethylamino)ethyl methacrylate) (PDEAEMA), and poly(poly(ethylene glycol) methyl ether methacrylate)(PPEGMA) were designed and synthesized by a combination of ring opening polymerization (ROP) and continuous activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP). The continuous ARGET ATRP of DEAEMA and PEGMA was in situ monitored by react infrared spectroscopy (ReactIR) and showed good first-order kinetic characteristics. The molecular weights and chemical structures of the copolymers and their precursors were confirmed by gel permeation chromatography (GPC) and 1H NMR. The critical micelle concentration (CMC) values of the star copolymers in aqueous solution were extremely low (2.2-4.0 mg/L), depending on the architecture of the copolymers. The pH-responsive self-assembly behavior of the star copolymers in aqueous solution was investigated by a combination of dynamic light scattering (DLS), UV-vis spectrometry and scanning electron microscopy (SEM). When the pH values decreased from 10 to 3, no obvious fluctuation of the visible light transmittance of the micelle solutions was observed for lower polymer concentrations of 0.1 and 1 mg/mL, while sharp increase occurred at higher concentration of 10 mg/mL. The hydrodynamic diameters (Dh) of the micelle solutions appeared slight increase with the increase of concentration, and increased rapidly as the pH decreased from 10 to 4 followed by a slight decrease at pH 3. The effects of pH value on the zeta potentials exhibited almost the same tendency with the Dh. This may due to the fact that the protonation of tertiary amine groups in DEAEMA can induce the swelling of micelles. The PCL and PDEAEMA contents and the topological structures (4-or 6-arm) showed significant influences on the pH-sensitivity of the micelles. Overall, the results demonstrated that the structures and pH-sensitivity of these amphiphilic copolymers could be well-controlled and their self-assembled micelles are promising carriers for delivery of anticancer hydrophobic drugs.

Dihydroartemisinin inhibits HepG2.2.15 proliferation by inducing cellular senescence and autophagy

( Jiang Zou ),( Qiang Ma ),( Ru Sun ),( Jiajing Cai ),( Hebin Liao ),( Lei Xu ),( Jingruo Xia ),( Guangcheng Huang ),( Lihua Yao ),( Yan Cai ),( Xiaowu Zhong ),( Xiaolan Guo ) 생화학분자생물학회(구 한국생화학분자생물학회) 2019 BMB Reports Vol.52 No.8

Dihydroartemisinin (DHA) has been reported to possess anti-cancer activity against many cancers. However, the pharmacologic effect of DHA on HBV-positive hepatocellular carcinoma (HCC) remains unknown. Thus, the objective of the present study was to determine whether DHA could inhibit the proliferation of HepG2.2.15 cells and uncover the underlying mechanisms involved in the effect of DHA on HepG2.2.15 cells. We found that DHA effectively inhibited HepG2.2.15 HCC cell proliferation both in vivo and in vitro. DHA also reduced the migration and tumorigenicity capacity of HepG2.2.15 cells. Regarding the underlying mechanisms, results showed that DHA induced cellular senescence by up-regulating expression levels of proteins such as p-ATM, p-ATR, γ-H₂AX, P53, and P21 involved in DNA damage response. DHA also induced autophagy (green LC3 puncta gathered together and LC3II/LC3I ratio increased through AKT-mTOR pathway suppression). Results also revealed that DHA-induced autophagy was not linked to senescence or cell death. TPP1 (telomere shelterin) overexpression could not rescue DHA-induced anticancer activity (cell proliferation). Moreover, DHA down-regulated TPP1 expression. Gene knockdown of TPP1 caused similar phenotypes and mechanisms as DHA induced phenotypes and mechanisms in HepG2.2.15 cells. These results demonstrate that DHA might inhibit HepG2.2.15 cells proliferation through inducing cellular senescence and autophagy. [BMB Reports 2019; 52(8): 520-525]

Progressive collapse of steel-framed gravity buildings under parametric fires

Jian Jiang,Wenyu Cai,Guo-Qiang Li,Wei Chen,Jihong Ye 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.36 No.4

This paper investigates the progressive collapse behavior of 3D steel-framed gravity buildings under fires with a cooling phase. The effect of fire protections and bracing systems on whether, how, and when a gravity building collapses is studied. It is found that whether a building collapses or not depends on the duration of the heating phase, and it may withstand a “short-hot” fire, but collapses under a mild fire or a “long-cool” fire. The collapse time can be conservatively determined by the time when the temperature of steel columns reaches a critical temperature of 550 °C. It is also found that the application of a higher level of fire protection may prevent the collapse of a building, but may also lead to its collapse in the cooling phase due to the delayed temperature increment in the heated members. The tensile membrane action in a heated slab can be resisted by a tensile ring around its perimeter or by tensile yielding lines extended to the edge of the frame. It is recommended for practical design that hat bracing systems should be arranged on the whole top floor, and a combination of perimeter and internal vertical bracing systems be used to mitigate the fire-induced collapse of gravity buildings. It is also suggested that beam-to-column connections should be designed to resist high tensile forces (up to yielding force) during the cooling phase of a fire.

Overexpression of Cyclooxygenase-1 Correlates with Poor Prognosis in Renal Cell Carcinoma

Yu, Zu-Hu,Zhang, Qiang,Wang, Ya-Dong,Chen, Jing,Jiang, Zhi-Mao,Shi, Min,Guo, Xin,Qin, Jie,Cui, Guang-Hui,Cai, Zhi-Ming,Gui, Yao-Ting,Lai, Yong-Qing Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

The aim of this study was to evaluate expression of COX-1 in renal cell carcinoma (RCC) and its prognostic value. mRNA of COX-1 was detected in 42 paired RCC and adjacent normal tissues with quantitative realtime polymerase chain reaction (qRT-PCR). Expression of COX-1 was also evaluated in 196 RCC sections and 91 adjacent normal tissues with immunohistochemistry. Statistical analysis was performed to assess COX-1 expression in RCC and its prognostic significance. The results of qRT-PCR showed mRNA levels of COX-1 in RCC tissues to be significantly higher than that in adjacent normal tissues (p < 0.001). Immunohistochemical assays also revealed COX-1 to be overexpressed in RCC tissues (p < 0.001). Statistical analysis demonstrated high expression of COX-1 was correlated with tumour size (p = 0.002), pathological stage (p = 0.003), TNM stage (p = 0.003, 0.007, 0.027, respectively), and tumour recurrence (p < 0.001). Survival analysis indicated patients with high expression of COX-1 had shorter survival time (p < 0.001), and COX-1 was an independent predictor. This is the first study to reveal overexpression of COX-1 in RRC and point to use as a prognostic marker in affected patients.

중국 Zhangjiakou시에서의 집수면 연구

( K. F. Andrew Lo ),( Zhong Ke Wang ),( Qiang Guo Cai ) 빗물학회 2002 빗물모으기운동 국제워크샵 Vol.2 No.-

The 2518 A/G Polymorphism in the MCP-1 Gene and Cancer Risk: A Meta-analysis

Jia, Liu-Qun,Shen, Yong-Chun,Guo, Shu-Jin,Hu, Qian-Jing,Pang, Cai-Shuang,Wang, Tao,Chen, Lei,Wen, Fu-Qiang Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

Background: The 2518 A/G polymorphism in the MCP-1 gene has been extensively studied for association swith cancer; however, results from replication studies have been inconsistent. The aim of this investigation was to determine links with risk of cancer by meta-analysis. Methods: We searched Pubmed, Embase, CNKI, Weipu and Wanfang databases, covering all case-control studies until March, 2013. Statistical analyses were performed using the Revman 5.0 software. Results: A total of 11 case-control studies met our inclusion criteria, including 1,422 cases and 2,237 controls. The results indicated that the MCP-1 2518 gene polymorphism had no association with cancer risk overall (GG vs.GA+ AA: OR = 0.89, 95%CI = 0.61-1.28, P = 0.52). However, in the subgroup analysis by ethnicity, a decrease of cancer risk was found in Asian populations (GG vs.GA+ AA: OR = 0.79, 95%CI = 0.63-0.99, P = 0.04). Conclusion: This meta-analysis suggested that the 2518A/G polymorphism of MCP-1 gene is associated with risk of cancer among Asian, but not in Caucasian populations.

Static Shape Adjustment and Actuator Layered Optimization for Planar Phased Array Satellite Antenna

Ji-Yang Zhou,Guang-Yu Lu,Guo-Ping CAI,Guang-Qiang Fang,Liang-Liang Lv,Jun-Wei Shi 한국항공우주학회 2019 International Journal of Aeronautical and Space Sc Vol.20 No.4

Shape accuracy is of great importance in space antennas, especially in large-scale planar phased array antenna. To maintain the performance of the planar phased array antenna, shape accuracy must be strictly controlled. This paper proposes an optimization method using diagonal cables as actuators to achieve the shape adjustment. As for shape control, actuator placement has a significant impact on the controlled shape accuracy. Misplaced actuators always lead to control problems, and the desired performance may not be achieved with any choice of control forces, so the actuator placement optimization is needed. The optimization problem is challenging because of the mixed discrete–continuous nature of design variables: the actuator placement corresponds to discrete variables and the control forces are continuous variables. A layered optimization method is proposed in this paper to solve the optimal actuator placement and the corresponding control forces. A genetic algorithm is applied in the outside layer to achieve the optimization of the actuator placement, and the quadratic programming method is used in the inside layer to get the corresponding optimal control forces. The proposed layered optimization method is successfully applied to the large-scale planar phased array antenna. Using this method, the influence of the number of actuators on the controlled shape accuracy is also studied.

Dynamic behavior analysis of push-the-bit rotary steerable bottom hole assembly

Zhi-chuan Guan,Heng Wang,Yu-cai Shi,Wei-qing Chen,Guo-shan Zhao,Jian-yun Wang,Guang-qiang Cao 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.4

Rotary steerable drilling technology is currently an advanced technology in the field of drilling engineering. A good understanding of dynamic behavior of rotary steerable system will benefit the drilling progress. Aimed at push-the-bit type of rotary steerable tool, finite element method was employed to model the rotary steerable bottom hole assembly (RSBHA) and establish the motion equation. Contact interaction between drill string and wellbore wall was analyzed and taken as the constraint condition in solving RSBHA motion equation. Force applied by steering pads was as the external force acting at the pads node. Then RSBHA motion state and bit lateral force were obtained by using Newmark method to solve the motion equation. A case was given and effects of influencing factors were analyzed. The results show that stick-slip phenomenon occurs under 60 r/min rotary speed condition and disappears when rotary speed rises to 90 r/min. Fully developed backward whirl comes into being at the near-bit stabilizer when rotary speed increases to 120 r/min. High weight on bit intensifies bit torsional vibration while larger pads’ steering force decreases the bit torsional vibration. Upper stabilizer plays a part in weakening RSBHA backward whirl under high rotary speed condition but reduces the inclination force. Time average of bit lateral force is mainly determined by pads’ steering force. Based on the results, corresponding suggestions were proposed to make the RSBHA be better used in the field applications.

Intensity-Modulated Radiotherapy versus Three-Dimensional Conformal Radiotherapy in Definitive Chemoradiotherapy for Cervical Esophageal Squamous Cell Carcinoma: Comparison of Survival Outcomes and Toxicities

Nai-Bin Chen,Bo Qiu,Jun Zhang,Meng-Yun Qiang,Yu-Jia Zhu,Bin Wang,Jin-Yu Guo,Ling-Zhi Cai,Shao-Min Huang,Meng-Zhong Liu,Qun Li,Yong-Hong Hu,Qi-Wen Li,Hui Liu 대한암학회 2020 Cancer Research and Treatment Vol.52 No.1

Purpose The purpose of this study was to compare the survival and toxicities in cervical esophageal squamous cell carcinoma (CESCC) treated by concurrent chemoradiothrapy with either three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) techniques. Materials and Methods A total of 112 consecutive CESCC patients were retrospectively reviewed. 3D-CRT and IMRT groups had been analyzed by propensity score matching method, with sex, age, Karnofsky performance status, induction chemotherapy, and tumor stage well matched. The Kaplan- Meier method and Cox proportional hazards model were used for overall survival (OS) and progression-free survival (PFS). Toxicities were compared between two groups by Fisher exact test. Results With a median follow-up time of 34.9 months, the 3-year OS (p=0.927) and PFS (p=0.859) rate was 49.6% and 45.8% in 3D-CRT group, compared with 54.4% and 42.8% in IMRT group. The rates of grade ! 3 esophagitis, grade ! 2 pneumonitis, esophageal stricture, and hemorrhage were comparable between two groups, while the rate of tracheostomy dependence was much higher in IMRT group than 3D-CRT group (14.3% vs.1.8%, p=0.032). Radiotherapy technique (hazard ratio [HR], 0.09; 95% confidence interval [CI], 0.01 to 0.79) and pretreatment hoarseness (HR, 0.12; 95% CI 0.02 to 0.70) were independently prognostic of tracheostomy dependence. Conclusion No survival benefits had been observed while comparing IMRT versus 3D-CRT in CESCC patients. IMRT with fraction dose escalation and pretreatment hoarseness were considered to be associated with a higher risk for tracheostomy dependence. Radiation dose escalation beyond 60 Gy should be taken into account carefully when using IMRT with hypofractionated regimen.

Green Tea Consumption May Be Associated with Cardiovascular Disease Risk and Nonalcoholic Fatty Liver Disease in Type 2 Diabetics: A Cross-Sectional Study in Southeast China

Huan-Huan Yang,Hui Zhou,Wan-Zhan Zhu,Cai-Long Chen,Guo-Chong Chen,Lu-Gang Yu,Li-qiang Qin 한국식품영양과학회 2020 Journal of medicinal food Vol.23 No.10

Dietary factors play a crucial role in the management of type 2 diabetes mellitus (T2DM) by reducing cardiovascular disease (CVD) risk. Therefore, we aimed to examine the associations between habitual green tea consumption and risk factors of CVD among T2DM patients. A total of 1013 patients with T2DM were included in a community-based cross-sectional study. Data on dietary habits, including tea consumption, were collected using a food frequency questionnaire. A multivariable logistic regression model was used to analyze the associations. In men, as compared with nongreen tea drinkers, odds ratios (ORs) (95% confidence interval [CI]) of nonalcoholic fatty liver disease (NAFLD) were 2.06 (95% CI, 1.20–3.55) for those with green tea consumption of once per day and 2.45 (95% CI, 1.31–4.58) for more than or equal to twice per day (P-trend = .004); ORs (95% CI) of general obesity were 2.19 (95% CI, 1.02–4.68) and 2.70 (95% CI, 1.18–6.21), respectively (P-trend = .021); whereas no such association was found in women. Sensitivity analysis according to self-awareness of their T2DM status revealed that the positive association between green tea consumption and general obesity was not reliable. Higher intake of green tea was still positively associated with NAFLD, but it only persisted in participants aged ≥52 years or the lower dietary quality subgroup in further analyses. Our findings suggest that tea consumption was associated with an increased risk of NAFLD among male T2DM patients aged 52 years or older, and those with lower dietary quality, which needs to be confirmed in future prospective studies.