74 results on '"Guang Wei Chen"'
Search Results
2. Dynamic analysis of lathe bed of woodworking CNC machining center based on the modeling of joint surface
- Author
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Yin-Kun Sun, Jun Hua, Yan-Na Li, Guang-Wei Chen, and Ming-Hui Liu
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Medicine ,Science - Abstract
Based on the finite element theory, a joint-plane modeling method is employed to connect the corresponding nodes at the joint surface of the woodworking computer numerical control (CNC) machining center bed with a 2-node 12-degree-of-freedom unit. A spatial element model is established, which can show the state of the nodes between joint surfaces when they are stretched, compressed, or twisted; and it can help build a woodworking CNC machining center on a finite element model of bed with the characteristics of the joint surface. The simulated analysis is performed on the model and is compared with the result of simulated analysis on the bed model that ignores the characteristics of the joint surface and modal experiment. The comparison verifies the effectiveness of the modeling method based on the characteristics of the joint surface. The weak link of the machine bed structure is analyzed and optimized. The natural frequency of the bed is improved by2.55% ~ 11.3%. The displacement is reduced by a maximum of 19.4%, and dynamic performance of the bed is improved.
- Published
- 2022
3. Research on Fault Diagnosis Method of Electric Submersible Plunger Pump Lifting Technology
- Author
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Kun Qian, Chun-long Sun, Qiang Li, Hong-liang Guo, Dong-zhi Zheng, Yun-long Zhao, Ji-nan Li, Feng-ying Wang, Xin Wei, Bao-zhong Zhang, Ying Zhang, and Guang-wei Chen
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- 2022
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4. [Antipyretic effect of active components of Mahuang Decoction and its correlation with pharmacokinetics in febrile rats]
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Guang-Wei, Chen, Yan-Fang, Tian, Hai-Tong, Wan, Jian-Zhen, Chen, and Yu, He
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Ephedra sinica ,Antipyretics ,Fever ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,Interleukin-1beta ,Animals ,Medicine, Chinese Traditional ,Drugs, Chinese Herbal ,Rats - Abstract
To investigate the antipyretic effect of active components of Mahuang Decoction in febrile rats, and explore its correlation with pharmacokinetics at different time points. The feverished rat models were induced by dry yeast, and intragastrically administered with the effective components of Mahuang Decoction with different orthogonal compatibility ratios. At different time points after administration, body temperature was measured; blood was taken from orbital vena plexus, and the contents of interleukin-6(IL-6), interleukin-1β(IL-1β), and tumor necrosis factor-α(TNF-α) in rat serum were determined with the kits. Combined with the pharmacokinetic data of the seven effective components in Mahuang Decoction, PK-PD(pharmacokinetics-pharmacodynamics) data fitting was conducted by using the analysis method of non-atrioventricular model, and then the pharmacodynamic parameters were calculated to determine the optimal binding model. The results showed that the effective components of Mahuang Decoction inhibited the release of heat-causing factors IL-6, IL-1β and TNF-α, and reduced the increase of body temperature. There was a significant lag between drug effect and blood drug concentration, which was consistent with Sigmoid-E_(max) model. The model fitting value showed a good correlation with mea-sured data, which could be used to evaluate and predict the correlation between PK and PD in Mahuang Decoction, and further applied to the multiple-indicator and multiple-effect study of PK-PD in other compound traditional Chinese medicines.
- Published
- 2020
5. Effects of shao-fu-zhu-yu-tang on motility of human sperm
- Author
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Ching-Chang Yang, Jung-Chou Chen, Guang-Wei Chen, Yi-shuan Chen, and J.G. Chung
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Spermatozoa -- Research ,Medicine, Chinese -- Dosage and administration ,Health - Published
- 2003
6. Modeling the Impact of Three Gorges Dam on the Cooling Energy Consumption of the Reservoir Cities
- Author
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Peter Davis, Waiching Tang, Guang Wei Chen, Yan Zhou, Shuo Chen, Min Wu, Yin Wang, Willy Sher, and Zhi Dan Qin
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Hydrology ,Consumption (economics) ,Weather data ,General Engineering ,Environmental engineering ,Environmental science ,Relative humidity ,Cooling energy ,Hydraulic machinery ,Three gorges - Abstract
While the Three George Dam might help in utilizing hydraulic power, historic weather data showed that the Three George Dam has a serious impact on the relative humidity for cities in the reservoir area. We conclude that the cooling energy consumption in Chongqing may have increased about 31 per cent, provided that the Three George Dam had not been constructed.
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- 2014
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7. A Cooling Vest for Construction Workers
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Waiching Tang, Joe Dong, Min Wu, Yin Wang, Andy Zhao, Guang Wei Chen, Willy Sher, Shuo Chen, Yan Zhou, and Zhi Dan Qin
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Engineering ,Architectural engineering ,business.industry ,General Engineering ,VEST ,skin and connective tissue diseases ,business ,Civil engineering ,Phase-change material ,Heat stress - Abstract
Construction workers are vulnerable to heat stress, and a number of heat-related injuries and deaths have been reported. This study thus introduces a phase change material (PCM) based cooling garment designed for construction workers. The PCM cooling garment will be effective in reducing the workers body temperature and can extend their maximum tolerable time on sites.
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- 2014
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8. Modelling Construction Dust Safety Distance
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Peter Davis, Waiching Tang, Min Wu, Guang Wei Chen, Zhi Dan Qin, Yin Wang, Yan Zhou, Willy Sher, and Shuo Chen
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Drill hole ,Solid gas ,Engineering ,Drill ,Mining engineering ,business.industry ,General Engineering ,Forensic engineering ,Drilling ,business - Abstract
Construction dust may lead to Silicosis, a disabling respiratory disease which severely threatens the life of construction workers. Therefore, it is important to predict and determine the safety area of dust generated by the construction process and the corresponding protective measures that must be adopted. In this paper, based on real site data, we modelled and simulated the pneumatic drill holes in rock drilling processes to analyze the dust distribution on construction sites. Our simulation results show that the dangerous distance from the pneumatic drill hole is 3.5m. Within the dangerous distance, the dust concentration ranged from 0.039 mg/m3to30mg/m3, and decreased as distance increases. Within the dangerous distance, dust alleviation technologies are strongly recommended and appropriate protective measures must be adopted by construction workers.
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- 2014
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9. The Design of Photoelectric Measuring System on Railway Track Parameters
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Guang Wei Chen
- Subjects
Engineering ,Brightness ,business.industry ,System of measurement ,Versine ,General Medicine ,Photoelectric effect ,Track (rail transport) ,Light source ,Trajectory ,Orbit (dynamics) ,Electronic engineering ,business ,Simulation - Abstract
Based on the analysis of the current railway track parameters measurement system, a digital system based on embedded processor is designed. The paper introduces the principle of the system , structure and methods. The system is still based on the deviation detection principle of three point method, using high brightness light source as a measurement point, in combination with linear CCD imaging features, completed the orbit measurement system of the digital processing, and through the network to complete the communication with PC. The photoelectric measuring system is realized in trajectory parameters of high accuracy and real time measurement; Also for the future development of tamping on railway cars plays a positive role.
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- 2013
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10. The Novel Approach 'One Drive for Multi-Plate ' in Lifting Garage System Design
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Guang Wei Chen
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Engineering ,business.industry ,Powertrain ,Systems design ,Point (geometry) ,General Medicine ,Fall protection ,business ,Simulation ,Automotive engineering - Abstract
Mechanical lifting garage is designed to achieve a variety of vehicles parked automatically and scientific storage storage facilities. Because the traditional design need one drives for each plate, it waste energy and increase the cost. This paper introduces the course of development of the lifting garage, status and various types of three-dimensional garage features. Then it takes two floors with five parking spaces lifting garage as an example, describing the working principle, the mechanical analysis, the main connection point of framework, and the driveline design. The design innovative use "one drive for multi-plate", reasonable design to achieve the lifting of the garage and pan. In addition, in order to ensure the safety of vehicles and personnel of the design also incorporates the gantry fall protection and other safety devices.
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- 2013
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11. The Effect of Reinforcement-Length of Carbon Fiber Reinforced Bonding Composites on Circular Tubes under Flexural Condition
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Guang Wei Chen, Li Chen, Ming Ma, Guo Li Zhang, and E Mei Di
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Materials science ,Flexural strength ,Bonding strength ,Composite number ,General Engineering ,Modulus ,Adhesive ,Composite material ,Reinforcement - Abstract
This paper presents an experimental investigation on flexural performance of carbon fiber reinforced bonding composite circular tubes with different length of reinforcing pieces. Four kinds of composites bonded tubes with different reinforcing pieces length 20mm, 30mm, 40mm and 50mm were carried out. The flexural strength and modulus of bonged composite samples tested were investigated. The experiment result indicates that the length of reinforcing pieces has some effects on the flexural performance of bonding composite circle tubes. The average flexural strengths of samples reinforced 20mm, reinforced 30mm, reinforced 40mm and reinforced 50mm are 41%, 45%, 49% and 51% of average flexural strength of boned samples without bonding, respectively. The bonding strength will improve when the length of reinforcing pieces increases. The modulus does not change when reinforcing length was greater or equal than 30mm. The main typical failure modes of tested specimens are adhesive cohesive failure and interlamination failure between prepreg and adhesive film.
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- 2011
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12. The Effect of Bonding Length on the Flexural Performance of Carbon Fiber Epoxy Matrix Composite Tubes
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Guo Li Zhang, E Mei Di, Guang Wei Chen, Li Chen, and Ming Ma
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Materials science ,Flexural strength ,Composite number ,General Engineering ,Adhesive ,Epoxy matrix ,Composite material ,Elastic modulus - Abstract
This paper attempts to explore the influence to flexural performance of carbon fiber epoxy matrix composite circular tubes which were bonded in four different bonding Length with adhesive. Under the different bonding length, i.e. 20, 25, 35 and 40mm, the flexural performance of carbon fiber epoxy matrix composite circular tubes which were bonded were tested. It is shown that the bonding length affect the flexural properties of composite tubes. The flexural strength and elastic modulus of specimens CFRL50 increase about 18.11% and 36.95% respectively, compared to specimens CFRL20. The flexural properties of bonding composite tubes increased with the increasing length of reinforced pieces L2. Embedded bonding technology can provide a good bonding performance for composite circle tubes.
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- 2011
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13. Study on the Compression Properties of Epoxy Matrix Composites Reinforced by PES Warp-Knitted Spacer Fabric
- Author
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Guo Li Zhang, Guang Wei Chen, Fu Lei Huo, Jia Lu Li, and Li Chen
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Materials science ,Flexural strength ,Coating ,Composite number ,General Engineering ,engineering ,Epoxy matrix ,Resilience (materials science) ,Composite material ,engineering.material ,Compression (physics) ,Elastic modulus - Abstract
This research paper presents an experimental investigation on the compression and compressive resilience properties of warp-knitted spacer fabric composites with different resin content and different kinds of resin. By means of hand roller coating technology, four kinds of warp-knitted spacer fabric composites were made. The experiments were tested according to GB/T1453-2005 and ISO3386/2:1984. It is shown that the resin content and resin type seriously affect the compression and compressive resilience properties of warp-knitted spacer fabric composite. The data indicated that when the warp-knitted spacer fabric composite coated with the same kind of resin, with increasing resin content the elastic modulus added and the compressive resilience decreased. Having the same resin content, the compression properties of pacer fabric composite increase with the increase of flexural strength of resin; while the compressive resilience decrease.
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- 2011
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14. The Effect of Reinforcement Structure on the Modal Parameters for Sandwich Structure Composite Plate
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Jia Lu Li, Ya Nan Wang, Fu You Wang, Guang Wei Chen, Li Chen, and Guo Li Zhang
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Materials science ,Torsional vibration ,business.industry ,Composite number ,General Engineering ,Natural frequency ,Structural engineering ,Modal ,Composite plate ,Woven fabric ,Composite material ,business ,Sandwich-structured composite ,Dynamic testing - Abstract
In order to investigate the effect of different reinforcement structure on the dynamic characteristics of sandwich structure composite plates used for manufacturing the high speed reciprocating motion composite components, four kinds of paulownia wood sandwich composite test specimens with dimensions of 350×83.5×9.5mm was designed and made by hand lay-up performing and press molding technology. The woven and 2D braiding fabric prepreg were both selected as top face and inner face materials , respectively, and the carbon fiber woven fabric prepreg was chosen as inner part materials. According to the impulse response modal test method, a modal test system was established. It was found that this kind of sandwich structure composite plate has bigger natural frequency value, it’s minimum natural frequency was about 609.77Hz that could meet the requirement for high speed reciprocating motion parts. The dynamic test results shown that the natural frequency of F2BAF-IUC-CPW sample is higher t about 11.17% at least, selecting 2D integral braiding pipe fabric as top face and inner face reinforced materials could effectively improve the dynamic properties of sandwich composite rectangular plates. The modal experiments indicated that the modal shapes of sandwich composite plate specimen with four kind reinforcement structures were identical, it’s 1st modal shape, 2nd modal shape and 3rd modal shape presented torsional vibration shape, flexural vibration shape and torsional flexural vibration shape, separately, the modal shapes of sandwich composite plate specimen were not obviously affected by reinforcement structure.
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- 2011
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15. The Theoretical Prediction and Experimental Verification of Modal Parameters for Carbon Fiber Reinforced Composites with Sandwich Structure
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Jia Lu Li, Ya Nan Wang, Li Chen, Guo Li Zhang, Guang Wei Chen, and Fu You Wang
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Torsional vibration ,Materials science ,business.industry ,Composite number ,General Engineering ,Natural frequency ,Structural engineering ,Test method ,Finite element method ,Vibration ,Modal ,Woven fabric ,Composite material ,business - Abstract
A innovative structure of sandwich composite rectangular plate with dimensions of 350 ×83.5×9.5mm was designed, it was made of unidirectional prepreg of carbon fibre and woven fabric prepreg of carbon fiber as face materials and paulownia as core material by hand lay-up performing and press molding technology for investigating the dynamic performance such as natural frequency and modal shapes. Based on testing the in-plane and out-plane mechanical properties of composite samples reinforced by unidirectional carbon fibre and carbon fiber woven fabric, a ANSYS FEA dynamic modeling was developed. According to the impulse response modal test method, a modal test system was established. The natural frequency test results showed that the minimum natural frequency of sandwich composite rectangular plate is about 616.45Hz which is higher about 27.5% than that of aluminum rectangular plate reinforced by carbon. The modal experiment indicated that the 1st modal shape, 2nd modal shape, 3rd modal shape and 4th modal shape of the sandwich composite rectangular plate were torsional vibration, flexural vibration shape, torsional flexural vibration and double-flexural vibration separately. It was found the calculating precision of FEA dynamic predication was very high, the dynamic predicating results by FEA could provide fundamental data to the optimal design high speed reciprocating sandwich composite rectangular parts.
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- 2011
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16. Analysis of the Additional Twists on the Fiber Band in Compact Field of Compact Spinning
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Jianping Yang, Han Guang Liu, Ting Fu, Jun Wang, and Guang Wei Chen
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Motion analysis ,Engineering ,Suction ,Field (physics) ,business.industry ,General Engineering ,Yarn ,Optics ,visual_art ,visual_art.visual_art_medium ,Fiber ,Tube (container) ,business ,Spinning - Abstract
Based on the analysis of the motion of fiber band in compact field, a mathematic model is proposed in this article. The factors affecting the additional twists and final twists of the compact spun yarn, such as diameter of the fiber band in the compact field, tilting angle of suction slot in profile tube and spinning speed, were discussed in detail. The validity of the model was validated by experiments.
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- 2011
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17. The Effect of Splicing Shape and Interval Length on the Failure Mode of Laminated Composites under Tensile Condition
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Guang Wei Chen, Fu You Wang, Guo Li Zhang, Li Chen, and Jia Lu Li
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Materials science ,business.industry ,Glass fiber ,General Medicine ,Epoxy ,Structural engineering ,Molding (process) ,Woven fabric ,visual_art ,Ultimate tensile strength ,visual_art.visual_art_medium ,Fiber ,Slippage ,business ,Failure mode and effects analysis - Abstract
This paper presents an experimental investigation on the failure modes of glass fiber reinforced 2D woven fabric with ladder splicing laminate composites. On the basis of [0/0/+45/90/-45/90]s ply sequence, six kinds of laminated performs with different splicing interval lengths which were 4mm, 8mm, 12mm respectively and two different splicing shape which were ladder splicing and double vertical line splicing, and a kind of laminated perform with continuous laminates of 2D glass fiber woven fabric were made. By means of RTM molding technology, the technological parameters of RTM processing were designed as follows: injection temperature was 25°C, injection duration time was 180min and injection pressure was 0.4MPa, the epoxy resin based 2D glass fiber woven fabric RTM laminated specimen were prepared. According to the GB/T 1447-2005 and GB/T 1449-2005standard test method, the failure modes of 2D glass fiber woven fabric laminated RTM specimen were tested. Results show that the failure modes of laminate composites manifest as rapid damage in the form of line inlay mode and wedge shape mode at 4mm interval length condition, and accumulating failure in the form of inlay layer slippage - fiber pulled out mode and fiber fracture - splicing layer deboning mode at 12mm interval length. Otherwise, all fracture position of splicing laminates occurs at the site of splicing line because of the concentration of tensile stress.
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- 2010
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18. Design and Manufacture of Three Dimensional Integrated Braided Composite Tube with Flange
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Jia Lu Li and Guang Wei Chen
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Engineering ,Compressive strength ,Consolidation (soil) ,Transfer molding ,Braided composite ,business.industry ,Volume fraction ,Composite number ,Ultrasonic sensor ,General Medicine ,Structural engineering ,Flange ,business - Abstract
In this paper, the design and manufacture technology of three dimensional(3D) integrated braided composite tube with flange are researched, including: braiding technology of 3D braided preform of tube with flange, the determination of process parameters of resin transfer molding(RTM) for 3D braided composite tube with flange, and the design of mould for consolidation of composite tube with flange. The fiber volume fraction of this component is calculated. The quality of composite tube with flange is good analyzed by ultrasonic A-scan. The maximum compressive force borne by composite tube flange is 56.65 kN, which has met the need of usage of 38 kN. The research result will provide a good way for designing and manufacturing high performance 3D integrated braided composite components with irregular shape.
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- 2010
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19. Effects of Heating Period of Time on Tensile Property of Plain Woven Fabric/Epoxy Resin Laminated Composites at High Temperature
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Gui Fang He, Guang Wei Chen, and Jia Lu Li
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Materials science ,Period (periodic table) ,Woven fabric ,visual_art ,Resin composite ,Ultimate tensile strength ,visual_art.visual_art_medium ,Laminated composites ,General Medicine ,Epoxy ,Fiber ,Composite material - Abstract
The purpose of this paper is to investigate the tensile property of laminated epoxy resin composites reinforced by carbon fiber plain woven fabric with different heating period of time at relatively high temperature. For this purpose, the tensile tests of laminated resin composites are carried out at 150°C and 180°C with 15 minutes, 10 hours and 30 hours heating period of time, respectively. The reasons for the variations of tensile property of these composites with different heating period of time at 150°C and 180°C are analyzed. At 150°C and 180 °C,with heating period of time increasing the tensile strength of samples keep the same level. However at 180 °C the average tensile strength of samples is decreased by 14.95% compared with that at 150°C and the variation coefficient (CV) of tensile strengths at 180°C is much more than that at 150°C. These show that the tensile strength of resin laminated composites is sensitive at high temperature, although the tensile strength of resin laminated composites keeps the same level at same temperature with different heating period of time. The reason of the tensile strength of resin laminated composites decreased at high temperature is that resin has been damaged,which losing the adhesion of fiber and resin, so that these make resin and fiber can not bear the tensile load together. The research results will provide a basic reference for the application of plain woven fabric reinforced laminated resin composites with long using period of time at high temperature.
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- 2010
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20. Nanoparticle/Epoxy Nanocomposites: Impact, Flexural and Thermal Properties
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Jia Lu Li, Zhiwei Xu, Guang Wei Chen, and Lei Chen
- Subjects
Nanocomposite ,Materials science ,General Engineering ,Nanoparticle ,Izod impact strength test ,Epoxy ,Carbon nanotube ,Dynamic mechanical analysis ,law.invention ,Flexural strength ,law ,visual_art ,Thermal ,visual_art.visual_art_medium ,Composite material - Abstract
Nanocomposites based on epoxy which were reinforced by different nanoparticles were fabricated. Five types of nanoparticles (corresponding to multi-walled carbon nanotubes (MWNTs), nano-Al2O3, nano-TiO2 and nano-SiO2) were chosen and the weight content of the nanoparticles was 2wt.%. Impact, flexural and thermal-mechanical properties of the nanocomposites were investigated. Compared with neat epoxy, impact strength of systems which were reinforced by MWNTs and nano-TiO2 was increased by 60%. Concerned with the flexural properties, there was also an increase of about 10%~50% with the addition of the some nanoparticles such as MWNTs, nano-TiO2 and nano-SiO2. The heat resistance of the EP was not decreased by adding nanoparticles and the thermal properties of the systems were even improved with the addition of MWNTs.
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- 2010
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21. Effects of Heating Period of Time on Tensile Property of Three-Dimension and Five-Direction Braided/Epoxy Resin Composites at High Temperature
- Author
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Guang Wei Chen, Jia Lu Li, and Gui Fang He
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Materials science ,Period (periodic table) ,Resin composite ,Long period ,visual_art ,Ultimate tensile strength ,General Engineering ,visual_art.visual_art_medium ,Epoxy ,Composite material ,Reinforcement ,Tensile testing - Abstract
The tensile tests of 3-dimension and 5-direction braided/epoxy resin composites were carried out at 150°C and 180°C with 15 minutes, 10 hours and 30 hours heating period of time, respectively. The reasons for the variations of tensile property of these composites with different heating period of time at 150°C and 180°C were analyzed. At 150°C and 180 °C,with heating period of time increasing the tensile strength of samples keeps the same level. the average tensile strength of samples at 180 °C is decreased only 5.0% compared with that at 150°C. The variation coefficient (CV) of tensile strengths at 180°C is also close to that at 150°C. These show that the tensile strength of 3-dimension and 5-direction braided/resin composites has no great change under 180 °C. However the resin in samples tested at 180°C is damaged more seriously than that at 150°C. The reason of damaged resin no great effect on tensile strength is that at high temperature, 3-dimension and 5-direction braided reinforcement still keeps an integrated structure, which can recuperate the loss of tensile strength made by resin damage. So the structure of reinforcement plays an important role at the tensile property of 3-dimension and 5-direction braided/resin composites at high temperature. The results derived from this paper will provide a useful reference for the application of 3-dimension and 5-direction braided/epoxy resin composites at high temperature and over a relatively long period of time.
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- 2010
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22. Study on the Tensile Strength Loss Rate of Glass Fiber 2D Woven Fabric Reinforced Laminates with Ladder Splicing
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Guang Wei Chen, Guo Li Zhang, Qiang Zhou, Li Chen, and Fu You Wang
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Materials science ,business.industry ,Glass fiber ,General Medicine ,Structural engineering ,Epoxy ,Molding (decorative) ,Woven fabric ,visual_art ,Ultimate tensile strength ,RNA splicing ,visual_art.visual_art_medium ,business ,Injection pressure ,Loss rate - Abstract
This research paper presents an experimental investigation on the tensile strength loss rate of glass fiber reinforced 2D woven fabric with ladder splicing laminate composites. On the basis of three kinds of ply sequence, two series of laminates with different plies numbers were prepared through RTM molding technology, including ladder splicing(LS) laminates and continuous laminates (CL). And the RTM technological parameters of RTM processing were designed as follows: injection temperature was room temperature, injection duration time was 180min and injection pressure was 0.5MPa, the epoxy resin based 2D glass fiber woven fabric RTM laminated specimen were prepared. According to the GB/T 1447-2005 standard test method, the tensile tests of the 2D glass fiber woven fabric laminates were carried out. Results show that the tensile strength loss rate of ladder splicing laminates is 11.05%, 9.37%, 7.78% while the number of plies is 8, 10, 12 respectively. In other words, the tensile strength loss rate is reduced with the plies number increasing. In addition, because of the concentration of tensile stress, all fractures of ladder splicing laminates occur at the site of splicing line.
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- 2010
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23. Experimental Researches on Temperature-Dependent Tensile Properties of Laminated Resin Composites Reinforced by Plain Woven Fabric
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Gui Fang He, Jia Lu Li, and Guang Wei Chen
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Materials science ,Resin composite ,Woven fabric ,Composite number ,Ultimate tensile strength ,Biaxial tensile test ,Laminated composites ,General Medicine ,Fiber ,Composite material ,Tensile testing - Abstract
The purpose of this paper is to investigate the tensile property of laminated resin composites reinforced by carbon fiber plain woven fabric at relatively high temperature. For this purpose, the tensile tests of laminated resin composites are carried out at room temperature(20°C) and high temperature(150°C and 180°C). The effect rules of different temperature on the tensile property of these composites are discussed. The reasons for the variations of tensile property of these composites at different temperature are also analyzed. At 150 °C and 180 °C, the tensile strength of laminated composite decreased by 13.3% and 34.42% respectively, compared with that at room temperature, which shows that the tensile strength of resin laminated composites is sensitive at high temperature. The reason of the tensile strength of resin laminated composites declined at high temperature is that resin has been damaged and can not transfer tensile load, which makes resin and fiber can not bear the tensile load together at high temperature. The research results will provide a basic reference for the application of plain woven fabric reinforced resin laminated composites at room temperature to 180°C.
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- 2010
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24. Surface and Composite Interface of Carbon Fibre Modified by Pre-Irradiation
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Li Chen, Xiaoqing Wu, Zhiwei Xu, Liangsen Liu, and Guang Wei Chen
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Materials science ,Polymers and Plastics ,Composite number ,Carbon fibers ,Surface finish ,Epoxy ,Grafting ,Surface energy ,visual_art ,Ultimate tensile strength ,Materials Chemistry ,Ceramics and Composites ,visual_art.visual_art_medium ,Shear strength ,Composite material - Abstract
The γ-ray pre-irradiation induced method was employed to study the effect of chloroepoxypropane modification on the surface of carbon fibre (CF) and the interfacial properties of CF/epoxy. Systematic experimental work was conducted to determine the fibre surface topography, fibre surface energy, fibre tensile strength and interfacial adhesion of CF/epoxy before and after γ-ray pre-irradiation grafting. The roughness and surface energy were all found to increase significantly. The tensile strength of carbon fibres was improved marginally by γ-ray pre-irradiation. The surface modification of carbon fibres led to an improvement (at most 18.2%) of the interlaminar shear strength of CF/epoxy composites. The mechanisms of pre-irradiation of CF are proposed.
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- 2010
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25. Effects of Scutellariae Radix on gene expression in HEK 293 cells using cDNA microarray
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Li-Wei Lin, Nae-Jing Chen, Chia-Chang Hsieh, Guang-Wei Chen, Chia-Sheng Chen, and Ming-Tsuen Hsieh
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Pharmacology ,Genetics ,Regulation of gene expression ,Candidate gene ,Microarray ,Plant Extracts ,Reverse Transcriptase Polymerase Chain Reaction ,Gene Expression Profiling ,HEK 293 cells ,Anti-Inflammatory Agents ,Biology ,Interferon-Stimulated Gene Factor 3, gamma Subunit ,Cell biology ,Gene expression profiling ,Gene Expression Regulation ,Complementary DNA ,Drug Discovery ,Gene expression ,Cytokine Receptor gp130 ,Humans ,Gene ,Cells, Cultured ,Oligonucleotide Array Sequence Analysis ,Scutellaria baicalensis - Abstract
The aim of the present study was to elucidate the molecular mechanisms underlying the anti-inflammatory effect of Scutellaria Radix (SR). The complementary DNA (cDNA) microarray method was used to survey the effects of SR on the changes of gene expression profile in HEK293 cells. Based on differential expression, 66 genes were selected for further analysis from 9,600 candidate genes in the microarray; 23 genes were validated by RT-PCR. The broad spectrum of the differentially expressed genes, including those associated with inflammation, immune response, energy metabolism, as well as others, such as ISGF3G, IL6ST, CD98, ATP5G2, PHKG2, YB-1 and SLC7A4, indicate overall cellular response to SR treatment. Our results suggest that the anti-inflammatory effect of SR may be related to IL6ST down-expression, and over-expression of CD98. Moreover, SR-related improvement in immune response may be related to the ISGF3G over-expression.
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- 2006
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26. Aloe-Emodin Induces Apoptosis in T24 Human Bladder Cancer Cells Through the p53 Dependent Apoptotic Pathway
- Author
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Tzu Wei Tan, Jaung Gung Lin, Guang Wei Chen, Se Tze Chouh, Jing Gung Chung, and Te-Mao Li
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Cyclin-dependent kinase 1 ,Programmed cell death ,Emodin ,biology ,Urology ,Anthraquinones ,Apoptosis ,Cell cycle ,Aloe emodin ,chemistry.chemical_compound ,Wee1 ,Urinary Bladder Neoplasms ,chemistry ,Tumor Cells, Cultured ,Cancer research ,medicine ,biology.protein ,Humans ,Propidium iodide ,Viability assay ,Enzyme Inhibitors ,Tumor Suppressor Protein p53 ,medicine.drug - Abstract
We investigated the anticancer effect of AE (1,8-dihydroy-3-[hydroxymethyl]-anthraquione) in the T24 human bladder cancer cell line (Food Industry Research and Development Institute, Hsinchu, Taiwan) by studying apoptosis regulation.AE, which is purified from aloe vera leaves, has been reported to have antitumor activity. Cell viability, cell cycle and apoptosis were determined by flow cytometric methods. Levels of cyclins, cyclin-dependent kinase 1 and other enzyme were examined by Western blotting methods.AE inhibited cell viability, and induced G2/M arrest and apoptosis in T24 cells. AE increased the levels of Wee1 and cdc25c, and may have led to inhibition of the levels of cyclin-dependent kinase 1 and cyclin B1, which cause G2/M arrest. AE induced p53 expression and was accompanied by the induction of p21 and caspase-3 activation, which was associated with apoptosis. In addition, AE was associated with a marked increase in Fas/APO1 receptor and Bax expression but it inhibited Bcl-2 expression.AE induced apoptosis in T24 cells is mediated through the activation of p53, p21, Fas/APO-1, Bax and caspase-3.
- Published
- 2006
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27. Non-invasive in Situ Simultaneous Measurement of Multi-parameter Mechanical Properties of Red Blood Cell Membrane
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Yao-Xiong Huang, Tao Ji, Mei Tu, Jing Li, Wen-Xin Chen, Xuan Mao, and Guang-Wei Chen
- Subjects
Materials science ,Flexural modulus ,Biophysics ,General Medicine ,Plasticity ,Biochemistry ,Viscoelasticity ,Cell membrane ,Membrane ,medicine.anatomical_structure ,medicine ,Osmotic pressure ,Adhesive ,Elasticity (economics) ,Biomedical engineering - Abstract
The purpose of this study was to develop a new dynamic image analyzing technique that will give us the ability to measure the viscoelastic parameters of individual living red blood cells non-invasively, in situ and in real time. With this technique, the bending modulus KC, the shear elasticity mu and their ratio were measured under different temperatures, oxygen partial pressures and osmotic pressures. The results not only show the effects of external conditions on mechanical properties of cell membranes including deformability, flexibility, adhesive ability and plasticity, but also demonstrate that the technique can be used to measure cell membrane parameters continuously under several physiological and pathological conditions.
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- 2005
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28. Diallyl disulfide (DADS) induced apoptosis undergo caspase-3 activity in human bladder cancer T24 cells
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Jing-Gung Chung, Guang Wei Chen, C. C. Sue, Chun Shu Yu, Ssu Ching Chen, and H. F. Lu
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Poly Adenosine Diphosphate Ribose ,Programmed cell death ,Cell Survival ,Blotting, Western ,Apoptosis ,Caspase 3 ,DNA Fragmentation ,Toxicology ,Amino Acid Chloromethyl Ketones ,chemistry.chemical_compound ,Cell Line, Tumor ,CDC2-CDC28 Kinases ,Humans ,Disulfides ,Viability assay ,Caspase ,Oligonucleotide Array Sequence Analysis ,biology ,Reverse Transcriptase Polymerase Chain Reaction ,Diallyl disulfide ,Cyclin-Dependent Kinase 2 ,Antibodies, Monoclonal ,DNA, Neoplasm ,Hydrogen Peroxide ,Trypan Blue ,General Medicine ,Cell cycle ,Flow Cytometry ,Antineoplastic Agents, Phytogenic ,Molecular biology ,Allyl Compounds ,Enzyme Activation ,Urinary Bladder Neoplasms ,Biochemistry ,chemistry ,Caspases ,Cancer cell ,biology.protein ,Indicators and Reagents ,Food Science - Abstract
Diallyl disulfide (DADS), one of the major components of garlic (Allium sativum), is well known to have chemopreventative activity against human cancer such as colon, lung and skin. But the exact mechanism of the action is still unclear. In this study, we investigated how DADS--induced cell cycle arrest and apoptosis in T24 human bladder cancer cells in vitro. Apoptosis induction, cell viability, cell cycle arrest, caspases-3, -9 activity and gene expression were measured to determine their variation by flow cytometric assay, western blot, and determination of caspase-3 activity, PCR and cDNA microarray. There are significant differences in cell death (decreased viable cells then increased the amounts of apoptosis) of T24 cells that were detected between DADS (5-75 microM) treated and untreated groups. A significant increase was found in apoptosis induction when cells were treated with DADS (50 microM) compared to without DADS treated groups. DADS also promoted caspase-3 activity after exposure for 1, 3, 6, 12, and 24 h, which led to induce apoptosis. DADS also increased the product of intracellular hydrogen peroxide. Furthermore, the DADS-induced apoptosis on T24 cells was blocked by the broad-spectrum caspase inhibitor, z-VAD-fmk and antioxidant (catalase). DADS also increased cyclin E and decreased CDK2 gene expression which may lead to the G2/M arrest of T24 cells.
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- 2004
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29. Effects of berberine on arylamine N-acetyltransferase activity in human bladder tumour cells
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C. B. Chu, T. F. Wang, M. F. Tsou, J. Y. Jan, Jing Gung Chung, L. T. Wu, Guang Wei Chen, Hsueh Fu Lu, Jia-Hsuan Lin, and C. C. Ho
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endocrine system ,Berberine ,Arylamine N-Acetyltransferase ,Toxicology ,Substrate Specificity ,chemistry.chemical_compound ,Tumor Cells, Cultured ,medicine ,4-Aminobenzoic acid ,Humans ,Enzyme Inhibitors ,Arylamine N-acetyltransferase activity ,Fluorenes ,Urinary bladder ,Arylamine N-acetyltransferase ,Chemistry ,Alkaloid ,fungi ,Biological activity ,General Medicine ,Molecular biology ,body regions ,Kinetics ,medicine.anatomical_structure ,Urinary Bladder Neoplasms ,Biochemistry ,Nat ,Carcinogens ,4-Aminobenzoic Acid ,Food Science - Abstract
Berberine was used to determine inhibition of arylamine N-acetyltransferase (NAT) activity in human bladder tumour cells. The NAT activity was measured by HPLC assaying for the amounts of N-acetyl-2-aminofluorene (AAF) and N-acetyl-p-aminobenzoic acid (N-Ac-PABA) and remaining 2-aminofluorene (AF) and p-aminobenzoic acid (PABA). Two assay systems were performed, one with cellular cytosols, the other with intact bladder tumour cell suspensions. The NAT activity in human bladder tumour cells was inhibited by berberine in a dose-dependent manner, that is, the higher the concentration of berberine, the higher the inhibition of NAT activity. The values of apparent Km and Vmax calculated from cytosol NAT and intact cells were also decreased by berberine. This report is the first demonstration to show berberine did affect human bladder tumour cell NAT activity.
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- 1999
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30. Effects of the garlic compounds diallyl sulphide and diallyl disulphide on arylamine N-acetyltransferase activity inKlebsiella pneumoniae
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Juang Geng Lin, Heng Chien Ho, Guang Wei Chen, and Jing Gung Chung
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chemistry.chemical_classification ,biology ,Arylamine N-acetyltransferase ,Chemistry ,Klebsiella pneumoniae ,Stereochemistry ,N-acetyltransferase ,Toxicology ,biology.organism_classification ,Enterobacteriaceae ,Molecular biology ,Enzyme ,Anticarcinogen ,Arylamine N-acetyltransferase activity ,Antibacterial agent - Abstract
Arylamine N-acetyltransferase (NAT) activities with 2-aminofluorene (2-AF) were determined in the bacterium Klebsiella pneumoniae. Cytosols or suspensions of K. pneumoniae with or without specific concentrations of diallyl sulphide (DAS) or diallyl disulphide (DADS) as co-treatment showed different percentages of 2-AF acetylation. The data indicated that there was decreased NAT activity associated with increased levels of DAS or DADS in K. pneumoniae. In growth studies on K. pneumoniae it was demonstrated that DAS or DADS elicited a dose-dependent bacteriocide effect on K. pneumoniae. For the cytosol examinations, the apparent values of Km and Vmax were 0.96+/-0.09 mM and 7.87+/-0.79 nmol min(-1) mg(-1) protein, respectively, for 2-AF. However, when DAS or DADS was added to the reaction mixtures, the apparent values of Km and Vmax were 0.16+/-0.04 mM and 0.99+/-0.16 nmol min(-1) mg(-1) protein with DAS, respectively, and 0.14+/-0.18 mM and 0.85+/-0.10 nmol min(-1) mg(-1) protein with DADS, respectively, for 2-AF. For the intact bacteria examination, the apparent values of Km and Vmax were 0.57+/-0.06 mM and 2.00+/-0.14 nmol min(-1) per 10x10(10) CFU, respectively, for 2-AF. However, when DAS or DADS was added to the reaction mixtures, the apparent of values of Km and Vmax were 0.41+/-0.04 mM and 1.30+/-0.10 nmol min(-1) per 10x10(10) CFU with DAS, respectively, and 0.34+/-0.04 mM and 1.08+/-0.08 nmol min(-1) per 10x10(10) CFU with DADS, respectively, for 2-AF. This report is the first demonstration to show that the garlic components DAS and DADS would affect K. pneumoniae growth and NAT activity.
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- 1999
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31. Effects of Aspirin on Arylamine N-Acetyltransferase Activity in Klebsiella Pneumoniae
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Jing Gung Chung, Jem Mi Lai, Wen Tsong Hsieh, Guang Wei Chen, Huei Yann Tsai, and Tzu Wei Tan
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Time Factors ,Arylamine N-Acetyltransferase ,Klebsiella pneumoniae ,Health, Toxicology and Mutagenesis ,Pharmacology ,Toxicology ,Microbiology ,Cytosol ,medicine ,Chromatography, High Pressure Liquid ,Arylamine N-acetyltransferase activity ,chemistry.chemical_classification ,Fluorenes ,Aspirin ,Chemical Health and Safety ,biology ,Arylamine N-acetyltransferase ,Public Health, Environmental and Occupational Health ,Acetylation ,General Medicine ,biology.organism_classification ,Enterobacteriaceae ,Enzyme ,chemistry ,Toxicity ,medicine.drug - Abstract
This study was designed to assess the effects of aspirin on arylamine N-acetyltransferase (NAT) activities in the bacterium Klebsiella pneumoniae using high performance liquid chromatography to measure the acetylation of 2-aminofluorene (2-AF) with or without aspirin. Cytosols or suspensions of K. pneumoniae with or without specific concentrations of aspirin co-treatment showed different percentages of 2-AF acetylation. The data indicated that there was decreased NAT activity associated with increased levels of aspirin in K. pneumoniae cytosols and in intact bacteria. For the cytosol examination, the apparent values of Km and Vmax decreased 0.59- and 0.58-fold after co-treated with 40 microM aspirin, respectively, for 2-AF. For the intact bacteria examination, the apparent values of Km and Vmax decreased 0.60- and 0.67-fold after co-treated with 40 microM aspirin, respectively, for 2-AF. This report is the first demonstration to show that aspirin can decrease N-acetyltransferase activity in the bacterium K. pneumoniae.
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- 1998
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32. ChemInform Abstract: Synthesis of Various Substituted Spiro- and Bicyclethiazolidine-2-thiones by a Multicomponent Reaction and Biological Evaluation in vitro
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Xiao-Juan Wang, Xiao Guo, Guang-Wei Chen, Hong-Min Liu, En Zhang, Lin-Lin Guo, and Haiwei Xu
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Chemistry ,Organic chemistry ,General Medicine ,Combinatorial chemistry ,In vitro ,Biological evaluation - Abstract
10 Title compounds of type (IV) and 8 of type (VI) and (VIII) are prepared and tested in vitro for their inhibitory effects on various human tumors.
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- 2011
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33. Stereoselective synthesis of desloratadine derivatives as antagonist of histamine
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Guang-Wei Chen, Haiwei Xu, De-Quan Yu, Gai-Zhi Liu, Ya-Na Wang, Hong-Min Liu, and Peng Wang
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Male ,Models, Molecular ,Histamine H1 Antagonists, Non-Sedating ,Spectrometry, Mass, Electrospray Ionization ,Spectrophotometry, Infrared ,Stereochemistry ,medicine.medical_treatment ,Clinical Biochemistry ,Rupatadine ,Guinea Pigs ,Pharmaceutical Science ,In Vitro Techniques ,Biochemistry ,chemistry.chemical_compound ,Drug Discovery ,medicine ,Animals ,Molecular Biology ,Butenolide ,chemistry.chemical_classification ,Desloratadine ,Chemistry ,Organic Chemistry ,Antagonist ,Stereoisomerism ,Loratadine ,Molecular Medicine ,Stereoselectivity ,Antihistamine ,Lactone ,Histamine ,medicine.drug - Abstract
A series of desloratadine derivatives were stereoselectively synthesized and evaluated for H 1 antihistamine activity. For the evaluation of H 1 antihistamine activity, the in vitro histamine-induced contraction of the guinea-pig ileum assay (HC) was used. The synthesized desloratadine derivatives 7 , 8 and 9 are structurally related to rupatadine and were generated by replacement of the 5-methyl-3-pyridine group of rupatadine with γ-alkylidene butenolide. Their H 1 antihistamine activities have shown a high dependence on the exact nature of the substituent in the lactone ring. Optimum structures 7 , 8a and 8g display potent activity inhibiting histamine-induced effects.
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- 2009
34. Involvement of reactive oxygen species and caspase-dependent pathway in berberine-induced cell cycle arrest and apoptosis in C6 rat glioma cells
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Kuang Chi Lai, Te Chun Hsia, Jen Jyh Lin, Hui Ju Lin, Yih Jing Tang, Jing Gung Chung, Jai Sing Yang, Ching Lung Liao, Ting Ching Chen, Tsan Hung Chiu, and Guang Wei Chen
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G2 Phase ,Cancer Research ,Programmed cell death ,Berberine ,Blotting, Western ,Apoptosis ,Endoplasmic Reticulum ,chemistry.chemical_compound ,Cell Line, Tumor ,Animals ,Enzyme Inhibitors ,Caspase ,bcl-2-Associated X Protein ,Membrane Potential, Mitochondrial ,biology ,Cytochrome c ,Cytochromes c ,Glioma ,Flow Cytometry ,Caspase Inhibitors ,Cell biology ,Mitochondria ,Rats ,Blot ,Oncology ,chemistry ,Proto-Oncogene Proteins c-bcl-2 ,Cell culture ,Caspases ,biology.protein ,DNA fragmentation ,Calcium ,Reactive Oxygen Species ,Cell Division ,DNA Damage - Abstract
The cytotoxicity of berberine on C6 rat glioma cells indicated that berberine induced morphological changes and caused cell death through G2/M arrest and apoptosis. While undergoing apoptosis, there was a remarkable accumulation of G2/M cells with the upregulatoin of Wee1 but it also inhibited cyclin B, CDK1 and Cdc25c that led to G2/M arrest. Along with cytotoxicity in C6 cells, several apoptotic events including mitochondrial cytochrome c release, activation of caspase-9, -3 and -8 and DNA fragmentation were induced. Berberine increased the levels of GADD153 and GRP 78 in C6 cells based on the examination of Western blotting and this is a major hallmark of endoplasmic reticulum (ER) stress. We also found that berberine promoted the production of reactive oxygen species and Ca2+ in C6 cells. Western blotting assay also showed that berberine inhibited the levels of anti-apoptotic protein Bcl-2 but increased the levels of pro-apoptotic protein Bax before leading to a decrease in the levels of mitochondrial membrane potential (DeltaPsim) followed by cytochrome c release that caused the activations of capase-9 and -3 for apoptotic occurrence. The caspase-8, -9 and -3 were activated by berberine in C6 cells based on the substrate solution (PhiPhiLux-G1D1, CaspaLux 8-L1D2, CaspaLux 9-M1D2 for caspase-3, -8 and -9, respectively) and analyzed by flow cytometer and each inhibitor of caspase-8, -9 and -3 led to increase the percentage of viable C6 cells after exposure to berberine. This finding was also confirmed by Western blot assay which showed that berberine promoted the active form of caspase-8, -9 and -3. These results demonstrate that the cytotoxicity of berberine in C6 rat glioma cells is attributable to apoptosis mainly through induced G2/M-arrested cells, in an ER-dependent manner, via a mitochondria-dependent caspase pathway regulated by Bax and Bcl-2.
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- 2009
35. The roles of endoplasmic reticulum stress and Ca2+ on rhein-induced apoptosis in A-549 human lung cancer cells
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Te-Chun, Hsia, Jai-Sing, Yang, Guang-Wei, Chen, Tsan-Hung, Chiu, Hsu-Feng, Lu, Mei-Due, Yang, Fu-Shun, Yu, Kuo-Ching, Liu, Kuang-Chi, Lai, Chin-Chung, Lin, and Jing-Gung, Chung
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Membrane Potential, Mitochondrial ,Lung Neoplasms ,Microscopy, Confocal ,Blotting, Western ,G1 Phase ,Cyclin-Dependent Kinase 4 ,Anthraquinones ,Apoptosis ,Cyclin-Dependent Kinase 6 ,Endoplasmic Reticulum ,Flow Cytometry ,Caspase Inhibitors ,Resting Phase, Cell Cycle ,Cell Line, Tumor ,Cyclins ,Humans ,Calcium ,Cyclin D3 ,Enzyme Inhibitors ,Reactive Oxygen Species ,Egtazic Acid ,Endoplasmic Reticulum Chaperone BiP ,Oligopeptides - Abstract
Although rhein has been shown to induce apoptosis in several cancer cell lines, the mechanism of action of rhein-induced cell cycle arrest and apoptosis at the molecular level is not well known. In this study, the mechanism of rhein action on A-549 human lung cancer cells was investigated. Rhein induced G0/G1 arrest through inhibition of cyclin D3, Cdk4 and Cdk6. The efficacious induction of apoptosis was observed at 50 microM for 12 h and up to 72 h as examined by a flow cytometric method. Flow cytometric analysis demonstrated that rhein increased the levels of GADD153 and GRP78, both hallmarks of endoplasmic reticulum stress, promoted ROS and Ca2+ production, induced the loss of mitochondrial membrane potential (delta psi(m)), promoted cytochrome c release from mitochondria, promoted capase-3 activation and led to apoptosis. Rhein also increased the levels of p53, p21 and Bax but reduced the level of Bcl-2. The Ca2+ chelator BAPTA was added to the cells before rhein treatment, thus blocking the Ca2+ production and inhibiting rhein-induced apoptosis in A-549 cells. Our data demonstrate that rhein induces apoptosis in A-549 cells via a Ca2+ -dependent mitochondrial pathway.
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- 2009
36. Emodin induces apoptosis of human tongue squamous cancer SCC-4 cells through reactive oxygen species and mitochondria-dependent pathways
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Shuw-Yuan, Lin, Wan-Wen, Lai, Chin-Chin, Ho, Fu-Shun, Yu, Guang-Wei, Chen, Jai-Sing, Yang, Kuo-Ching, Liu, Meng-Liang, Lin, Ping-Ping, Wu, Ming-Jen, Fan, and Jing-Gung, Chung
- Subjects
Cyclin-Dependent Kinase Inhibitor p21 ,G2 Phase ,Membrane Potential, Mitochondrial ,Emodin ,Caspase 3 ,Apoptosis ,Cyclin B ,Protein Serine-Threonine Kinases ,Caspase 9 ,Cyclin-Dependent Kinases ,Mitochondria ,Tongue Neoplasms ,Checkpoint Kinase 2 ,CDC2 Protein Kinase ,Carcinoma, Squamous Cell ,Humans ,Calcium ,Cyclin B1 ,Reactive Oxygen Species ,Endoplasmic Reticulum Chaperone BiP ,Cell Division ,DNA Damage - Abstract
Emodin was isolated from Rheum palmatum L. and exhibits an anticancer effect on human cancer cell lines, however, the molecular mechanisms of emodin-mediated apoptosis in human tongue cancer cells have not been fully investigated. In this study, treatment of human tongue cancer SCC-4 cells with various concentrations of emodin led to G2/M arrest through promoted p21 and Chk2 expression but inhibited cyclin B1 and cdc2; it also induced apoptosis through the pronounced release of cytochrome c from mitochondria and activations of caspase-9 and caspase-3. These events were accompanied by the generation of reactive oxygen species (ROS), disruption of mitochondrial membrane potential (delta psi(m)) and a decrease in the ratio of mitochondrial Bcl-2 and Bax content; emodin also promoted the levels of GADD153 and GRP78. The free radical scavenger N-acetylcysteine and caspase inhibitors markedly blocked emodin-induced apoptosis. Taken together, these findings suggest that emodin mediated oxidative injury (DNA damage) based on ROS production and ER stress based on the levels of GADD153 and GRP78 that acts as an early and upstream change in the cell death cascade to caspase- and mitochondria-dependent signaling pathways, triggers mitochondrial dysfunction from Bcl-2 and Bax modulation, mitochondrial cytochrome c release and caspase activation, consequently leading to apoptosis in SCC-4 cells.
- Published
- 2009
37. Inhibition of lipopolysaccharide-induced interleukin-1beta and tumor necrosis factor-alpha production by menthone through nuclear factor-kappaB signaling pathway in HaCat cells
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Hui-Man, Cheng, Chien-Yun, Hsiang, Guang-Wei, Chen, Shih-Lu, Wu, Jaw-Chyun, Chen, Chih-Yang, Huang, Da-Tian, Bau, and Tin-Yun, Ho
- Subjects
Keratinocytes ,Lipopolysaccharides ,Tumor Necrosis Factor-alpha ,Interleukin-1beta ,Anti-Inflammatory Agents ,NF-kappa B ,Hydrogen Peroxide ,Ceramides ,beta-Transducin Repeat-Containing Proteins ,Cell Line ,Menthol ,Okadaic Acid ,Humans ,Tetradecanoylphorbol Acetate ,I-kappa B Proteins ,Medicine, Chinese Traditional ,Signal Transduction - Abstract
Menthone, the Chinese old remedy extracted from genus Mentha, has been widely used as a cooling agent, a counterirritant for pain relief, and for the treatment of pruritus. However, its detail mechanisms for interfering inflammatory reaction remain unknown. In this study, we found that menthone can suppress the lipopolysaccharide (LPS)-induced proinflammatory cytokines, interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), as well as nuclear factor kappaB (NF-kappaB) activity induced by LPS and other inflammatory agents, including 12-O-tetradecanoylphorbol-13-acetate, hydrogen peroxide, okadaic acid, and ceramide. Furthermore, our data also demonstrated that the translocation of NF-kappaB activated by LPS into the nucleus was suppressed by menthone, and I-kappaB and beta-transducin repeat containing protein (beta-TrCP) were both involved in this suppression. To sum up, this study has provided molecular evidence for menthone effect on the LPS-induced cytokine production, NF-kappaB activation, and the involvement of I-kappaB and beta-TrCP.
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- 2008
38. Growth inhibition and apoptosis induction by tanshinone IIA in human colon adenocarcinoma cells
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Ming-Huan Chan, Chin-Cheng Su, Jung-Cheng Kang, and Guang-Wei Chen
- Subjects
Programmed cell death ,BALB 3T3 Cells ,Colorectal cancer ,Pharmaceutical Science ,Adenocarcinoma ,Analytical Chemistry ,chemistry.chemical_compound ,Mice ,Cell Line, Tumor ,Drug Discovery ,medicine ,Animals ,Humans ,Caspase ,Cell Proliferation ,Pharmacology ,TUNEL assay ,biology ,Cell growth ,Organic Chemistry ,Phenanthrenes ,medicine.disease ,Complementary and alternative medicine ,Biochemistry ,chemistry ,Apoptosis ,Abietanes ,Colonic Neoplasms ,biology.protein ,Cancer research ,Molecular Medicine ,Growth inhibition - Abstract
Tanshinone IIA is the most abundant diterpene quinone in Danshen, Salviae miltiorrhizae Radix, a widely prescribed traditional herbal medicine that is used to treat cardiovascular and inflammatory diseases. Recently, tanshinone IIA was demonstrated to induce cell death and apoptosis in a variety of tumors. However, the effect of tanshinone IIA on human colon cancer cells is not clearly understood yet. In this study, the antigrowth and apoptosis-eliciting effects of tanshinone IIA, as well as its cellular mechanisms of actions, were investigated in Colo-205 human colon cancer cells. Tanshinone IIA reduced cell growth in a concentration-dependent manner, inducing apoptosis accompanied by an increase in TUNEL staining and by an increased percentage of cells in the sub-G1 fraction. The expression of p53 and p21 and mitochondrial cytochrome c release were increased in tanshinone IIA-treated cells. In addition, the expression of Fas proteins was up-regulated by tanshinone IIA. Tanshinone IIA-induced catalytic activation of caspases was confirmed by cleavage of caspase-8 and caspase-3. These findings suggest that tanshinone IIA induces apoptosis in Colo-205 cells through both mitochondrial-mediated intrinsic and Fas-mediated extrinsic caspase cell-death pathways. Accordingly, the chemotherapeutic potential of tanshinone IIA for colon cancer warrants further study.
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- 2008
39. Crude extracts of Solanum lyratum induced cytotoxicity and apoptosis in a human colon adenocarcinoma cell line (colo 205)
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Shu-Chun, Hsu, Jih-Hung, Lu, Chao-Lin, Kuo, Jai-Sing, Yang, Meng-Wei, Lin, Guang-Wei, Chen, Chin-Cheng, Su, Hsu-Fung, Lu, and Jing-Gung, Chung
- Subjects
Membrane Potential, Mitochondrial ,Dose-Response Relationship, Drug ,Cell Survival ,Plant Extracts ,Cell Line, Tumor ,Colonic Neoplasms ,Drug Evaluation, Preclinical ,Humans ,Apoptosis ,DNA Fragmentation ,Adenocarcinoma ,Reactive Oxygen Species ,Solanum - Abstract
The effects of the crude extract of Solanum lyratum (SLE) on human colon cancer colo 205 cells were investigated. The cell viability, morphological changes of the cells, cell cycle arrest, apoptosis, reactive oxygen species (ROS), mitochondrial membrane potential (deltapsi(m)) and cell cycle- and apoptosis-associated protein levels and gene expressions were examined in colo 205 cells after exposure to various concentrations of SLE for different time periods. The results indicated that SLE decreased the percentage of viable colo 205 cells accompanied by morphological changes. The most effective concentration of SLE was 300 pg/ml (SLE 300) and this concentration was used for further investigations. SLE induced S-phase arrest and apoptosis (sub-G1) in the colo 205 cells and those effects were dose- and time-dependent. DAPI staining and DNA gel electrophoresis confirmed that SLE induced apoptosis in colo 205 cells. Flow cytometric analysis also showed that SLE 300 promoted ROS production and decreased the deltapsi(m). Western blotting analysis indicated that SLE 300 increased Bax levels and decreased Bcl-2 levels, which caused the loss of deltapsi(m) followed by cytochrome c release and caspase-9 and -3 activation, finally leading to apoptosis. SLE 300 also promoted p53 and p27, but decreased the levels of cyclin B1 thus causing S-phase arrest. The gene expression associated with those proteins was also confirmed by PCR methods. The findings show that SLE might be used as a colon cancer therapeutic agent in the future.
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- 2008
40. Berberine induced down-regulation of matrix metalloproteinase-1, -2 and -9 in human gastric cancer cells (SNU-5) in vitro
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Jing-Pin, Lin, Jai-Sing, Yang, Chih-Chung, Wu, Song-Shei, Lin, Wen-Tsong, Hsieh, Meng-Liang, Lin, Fu-Shun, Yu, Chun-Shu, Yu, Guang-Wei, Chen, Yung-Hsien, Chang, and Jing-Gung, Chung
- Subjects
Berberine ,Dose-Response Relationship, Drug ,Cell Survival ,Statistics as Topic ,Down-Regulation ,In Vitro Techniques ,Gene Expression Regulation, Enzymologic ,Gene Expression Regulation, Neoplastic ,Matrix Metalloproteinase 9 ,Stomach Neoplasms ,Cell Line, Tumor ,Humans ,Matrix Metalloproteinase 2 ,RNA, Messenger ,Matrix Metalloproteinase 1 - Abstract
Berberine, a yellow benzylisoquinoline alkaloid, is a constituent of Coptis chines and is commonly used in Chinese herbal medicine for patients with gastrointestinal disorders. The pharmacological effects of berberine include anti-inflammation, antidiarrhetic, antimalarial, and even antimicrobial activities. However, its mechanism of action on the cell migration of human gastric cancer SNU-5 cells is not fully understood. The effects of berberine on the percentage of viable cells were examined first and it was found that berberine induced dose-dependent inhibition in human gastric cancer SNU-5 cells. The effect of berberine on the levels of reactive oxygen species (ROS) and matrix metalloproteinase-1, -2, -7 and -9 was then examined using Western blotting and the results showed that berberine induced ROS production for up to 6 hours of incubation. It was also found that berberine induced downregulation of MMP-1 -2, and -9 but did not affect the level of MMP-7. The mRNA levels of MMPs in SNU-5 cells after treatment with berberine for 24 hours were investigated using a polymerase chain reaction and the results showed that berberine inhibited the gene expression of MMP-1, -2 and -9 in human SNU-5 cells but it did not affect MMP-7. In conclusion, berberine appears to exert its anticancer properties by inducing ROS production and prevention of cell migration via inhibition of the gene expression of MMP-1, -2 and -9 in human gastric cancer SNU-5 cancer cells.
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- 2008
41. The role of mitochondria in bee venom-induced apoptosis in human breast cancer MCF7 cells
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Siu-Wan, Ip, Shin-Shin, Liao, Shuw-Yuan, Lin, Jing-Pin, Lin, Jai-Sing, Yang, Meng-Liang, Lin, Guang-Wei, Chen, Hsu-Feng, Lu, Meng-Wei, Lin, Sang-Mi, Han, and Jing-Gung, Chung
- Subjects
Membrane Potential, Mitochondrial ,Time Factors ,Dose-Response Relationship, Drug ,Apoptosis ,Breast Neoplasms ,Cytochrome c Group ,Models, Biological ,Caspase 9 ,Mitochondria ,Bee Venoms ,Proto-Oncogene Proteins c-bcl-2 ,Cell Line, Tumor ,Humans ,Female ,Poly(ADP-ribose) Polymerases ,Reactive Oxygen Species ,bcl-2-Associated X Protein - Abstract
Our previous studies have shown that bee venom (BV) can induce apoptosis in human cervical cancer Ca Ski cells, but it can also affect human breast cancer cells, though its molecular mechanisms are not precisely known. In this study, the molecular mechanisms of apoptosis induced by BV in human breast cancer MCF7 cells were investigated. BV induced morphological changes (examined by phase-contrast microscopy) and inhibited the proliferation (examined by MTT assay) of MCF7 cells; both effects occurred in a dose- and time-dependent manner. Flow cytometric analysis demonstrated that BV induced the production of reactive oxygen species (ROS) and dysfunction of the mitochondrial membrane potential (Azm), and led to cytochrome c release, an increase in the levels of caspase-9 and Poly (ADP-ribose) polymerase (PARP) and then apoptosis. It also showed that BV induced S-phase arrest in MCF7 cells which may occur through the promotion of p53, p21, p27 and the exhibition of Cdk2. Western blotting demonstrated that BV reduced Bcl-2 and increased Bax protein levels which may have caused the changes of delta psi m. BV treatment led to ROS production up to but after treatment led to a decrease in the levels of ROS, which may be associated with the observations of BVaffecting glutathion S-transferase (GST), Zn-superoxide dismutase (Zn-SOD), Cu/Zn-superoxide dismutase (Cu/Zn-SOD) and catalase. The Comet assay also showed that BV induced DNA damage while DAPI staining also confirmed that BV induced apoptosis in examined MCF7 cells. Our results also showed that BV increased the levels of AIF and EndoG in MCF7 cells. In conclusion, our data demonstrated that BV induced apoptosis via a mitochondria-dependent pathway based on the changes of delta psi m, AIF and EndoG release in MCF7 cells.
- Published
- 2008
42. Gypenosides induced G0/G1 arrest via inhibition of cyclin E and induction of apoptosis via activation of caspases-3 and -9 in human lung cancer A-549 cells
- Author
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Hsu-Feng, Lu, Yi-Shan, Chen, Jai-Sing, Yang, Jung-Chou, Chen, Kung-Wen, Lu, Tsan-Hung, Chiu, Kuo-Ching, Liu, Chin-Chung, Yeh, Guang-Wei, Chen, Hui-Ju, Lin, and Jing-Gung, Chung
- Subjects
Lung Neoplasms ,Dose-Response Relationship, Drug ,Caspase 3 ,Plant Extracts ,G1 Phase ,Apoptosis ,Models, Biological ,Resting Phase, Cell Cycle ,Caspase 9 ,Gynostemma ,Up-Regulation ,Enzyme Activation ,Proto-Oncogene Proteins c-bcl-2 ,Cell Line, Tumor ,Cyclin E ,Humans ,Tumor Suppressor Protein p53 ,bcl-2-Associated X Protein - Abstract
Gynostemma pentaphyllum Makino is known in Asia for its effect on the treatment of hepatitis and cardiovascular diseases. Gypenosides (Gyp) are the major components extracted from Gynostemma pentaphyllum Makino. However, the molecular mechanism underlying the Gyp-induced cell cycle arrest and apoptotic process is unclear. In this study, the chemopreventive role of Gyp in human lung cancer (A549) cells in vitro was evaluated by studying the regulation of the cell cycle and apoptosis. Gyp induced GO/G1 arrest and apoptosis in the human lung cancer A549 cells. Investigation of the cyclin-dependent protein kinase inhibitors by Western blotting showed that p16, p21, p27 and p53 proteins were increased with the increasing time of incubation with Gyp in the A549 cells. This increase may be the major factor by which Gyp caused GO/G1 arrest in the examined cells. Flow cytometric assay and gel electrophoresis of DNA fragmentation also confirmed that Gyp induced apoptosis in the A549 cells. Our data demonstrated that Gyp-induced apoptotic cell death was accompanied by up-regulation of Bax, caspase-3 and caspase-9, but down-regulation of the Bcl-2 levels. Taken together, Gyp appears to exert its anticancer properties by inducing GO/GI-phase arrest and apoptosis via activation of caspase-3 in human lung A549 cancer cells.
- Published
- 2008
43. [Development of traditional Chinese medicine in Taiwan before 1960s]
- Author
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Guang-wei, Chen, Pei-chi, Chou, and Jaung-geng, Lin
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Taiwan ,Humans ,Medicine, Chinese Traditional - Abstract
It is important for people to view the early development of traditional Chinese medicine in Taiwan from a historical perspective as the World Health Organization (WHO) has already confirmed that traditional Chinese medicine is a great contribution to human civilization. In this article, we will introduce the early development of traditional Chinese medicine in Taiwan chronologically.
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- 2007
44. Curcumin-induced apoptosis of human colon cancer colo 205 cells through the production of ROS, Ca2+ and the activation of caspase-3
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Chin-Cheng, Su, Jaung-Geng, Lin, Te-Mao, Li, Jing-Gung, Chung, Jai-Sing, Yang, Siu-Wan, Ip, Wen-Chuan, Lin, and Guang-Wei, Chen
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Enzyme Activation ,Curcumin ,Caspase 3 ,Cell Line, Tumor ,Humans ,Apoptosis ,Calcium ,Comet Assay ,Flow Cytometry ,Reactive Oxygen Species - Abstract
Curcumin (diferuloylmethane), the yellow pigment in turmeric (Curcuma longa), is known to inhibit proliferation of cancer cells by arresting them at various phases of the cell cycle and to induce apoptosis in tumor cells. Curcumin-induced apoptosis mainly involves the activation of caspase-3 and mitochondria-mediated pathway in various cancer cells of different tissue origin. In the present study, the induction of apoptosis and cytotoxicity by curcumin in colon cancer colo 205 cells was investigated by using flow cytometry. The results demonstrated that curcumin induced cytotoxicity and apoptosis dose- and time-depedently. Curcumin induced the production of reactive oxygen species (ROS) and Ca+2, decreased the levels of mitochondria membrane potential and induced caspase-3 activity. Curcumin also promoted the expression of Bax, cytochrome C, p53 and p21 but inhibited the expression of Bcl-2. These observations suggest that curcumin may have a possible therapeutic potential in colon cancer patients.
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- 2007
45. Wogonin inhibits WEHI‐3 leukemia cells in Blab/C mice In Vivo
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Guang-Wei Chen, Chin-Cheng Su, Jing Gung Chung, and Nou-Ying Tang
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Leukemia ,chemistry.chemical_compound ,Wogonin ,chemistry ,In vivo ,Genetics ,medicine ,Cancer research ,medicine.disease ,Molecular Biology ,Biochemistry ,Biotechnology - Published
- 2007
- Full Text
- View/download PDF
46. Differential gene expression in hemodialysis patients with 'cold' zheng
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Guang-Wei Chen, Chia-Sheng Chen, Chia-Chang Hsieh, Ming-Tsuen Hsieh, Wen-Huang Peng, and Li-Wei Lin
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Male ,Gene Expression Profiling ,Serum albumin ,GNG11 ,General Medicine ,Biology ,Middle Aged ,Molecular biology ,Reverse transcriptase ,Gene expression profiling ,Real-time polymerase chain reaction ,Complementary and alternative medicine ,Renal Dialysis ,Complementary DNA ,Gene expression ,biology.protein ,Humans ,Kidney Failure, Chronic ,Female ,Medicine, Chinese Traditional ,Gene ,Aged - Abstract
The aim of the present study was to search for the differential gene expression and measure the serum level of a number of biochemical parameters in the cold Zheng (CZ) and non-cold Zheng (NCZ) in patients receiving hemodialysis. Hemodialysis (HD) patients were randomly selected from the CZ and NCZ groups. The between-group differences in gene expression were assessed using complementary DNA (cDNA) microarray. Differential gene expression was further validated by real-time reverse transcriptase polymerase chain reaction (RT-PCR). Our results demonstrated that the up-regulation of the inflammation-associated genes, ALOX5AP, S100A8 and S100A12, down-regulation of the genes related to immunity (DEFA4), metabolism (GNG11, PYGB, PRKAR2B), and growth/proliferation (HSF2, DDR2, TK1) were found in the CZ group. Furthermore, the CZ HD patients had significantly lower serum albumin levels compared with their NCZ counterparts (3.31 ± 0.08 g/dL versus 4.18 ± 0.12 g/dL ). It appears reasonable to conclude that up-regulated inflammatory-gene expression (ALOX5AP, S100A8 and S100A12) may play an important role in CZ HD patients.
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- 2006
47. Curcumin inhibits cell migration of human colon cancer colo 205 cells through the inhibition of nuclear factor kappa B /p65 and down-regulates cyclooxygenase-2 and matrix metalloproteinase-2 expressions
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Chin-Cheng, Su, Guang-Wei, Chen, Jaung-Geng, Lin, Lii-Tzu, Wu, and Jing-Gung, Chung
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Isoenzymes ,Curcumin ,Cell Movement ,Cyclooxygenase 2 ,Blotting, Western ,Colonic Neoplasms ,Cyclooxygenase 1 ,Transcription Factor RelA ,Down-Regulation ,Humans ,Matrix Metalloproteinase 2 ,Antineoplastic Agents ,RNA, Messenger - Abstract
Curcumin (diferuloylmethane) is a chemical derived from several Curcuma species (turmeric), possessing anti-inflammatory and antioxidant properties and which, thus, may be a potential anticancer drug. However, its mechanism of action is not fully understood. Our previous studies had shown that curcumin induced cytotoxicity, cell cycle arrest and apoptosis in human colon cancer colo 205 cells. In this study, curcumin affected the levels of NF-kappaB/ p65 in a time-dependent manner but did not affect NF-kappaB/ p50, based on Western blotting methods. In vitro experiments revealed that curcumin inhibited Cox-2 levels, but promoted those of Cox-1 in colo 205 cells. Curcumin also inhibited MMP-2 levels and promoted MMP-9 levels, but did not affect MMP-7 levels, based on Western blotting assays. These effects were also confirmed by cDNA microarray. Remarkably, curcumin not only exerted its effect on the protein levels of NF-kappaB, Cox-1 and -2, MMP-2 and -7, but also directly inhibited their mRNA levels. Curcumin was also found to significantly repress the in vitro invasion of colo 205 cells.
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- 2006
48. Down-regulation of cyclin B1 and up-regulation of Wee1 by berberine promotes entry of leukemia cells into the G2/M-phase of the cell cycle
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Chin-Chung, Lin, Shuw-Yun, Lin, Jing-Gung, Chung, Jing-Pin, Lin, Guang-Wei, Chen, and Shung-Te, Kao
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G2 Phase ,Berberine ,Blotting, Western ,Down-Regulation ,Nuclear Proteins ,Cell Cycle Proteins ,HL-60 Cells ,Cyclin B ,Protein-Tyrosine Kinases ,Flow Cytometry ,Up-Regulation ,14-3-3 Proteins ,Leukemia, Myeloid ,Cell Line, Tumor ,CDC2 Protein Kinase ,Cyclin E ,Animals ,Humans ,cdc25 Phosphatases ,Cyclin B1 ,Cell Division - Abstract
Berberine has a wide range of biological actions that suggest it may be of use in cancer prevention. It was previously reported that berberine induced cell cycle arrest, not only at the G0/G1-phase, but also at the G2/M-phase in a dose-dependent manner. However, the mechanism of berberine-induced G2/M-phase arrest in leukemia cells is not fully understood. In the present study, the effects of the naturally occurring berberine (the major constituent of Coptis chinensis) on the cell cycle, as well as on CDK1, cyclin B1, 14-3-3sigma, Wee1 and Cdc25c expressions, were investigated in the human promyelocytic leukemia HL-60 cells and in the murine myelomonocytic leukemia WEHI-3 cells. The flow cytometry assays indicated that berberine induced G2/M-phase arrest in both examined cell lines. The berberine-induced G2/M-phase arrest in both examined cell lines was accompanied by increased levels of Wee1 and 14-3-3sigma, but decreased levels of Cdc25c, CDK1 and cyclin B1. However, CDK2 expression was not affected as revealed by Western blotting assay. Berberine induced G2/M arrest in both the examined cells via the inhibition of cyclin B1 and the promotion of Wee1.
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- 2006
49. Diallyl disulfide inhibits WEHI-3 leukemia cells in vivo
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Jai-Sing, Yang, Lai-Fong, Kok, Yu-Hsuan, Lin, Tzu-Ching, Kuo, Jiun-Long, Yang, Chin-Chung, Lin, Guang-Wei, Chen, Wen-Wen, Huang, Heng-Chien, Ho, and Jing-Gung, Chung
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Allyl Compounds ,Male ,Mice ,Mice, Inbred BALB C ,Liver ,Leukemia, Myeloid ,Cell Line, Tumor ,Animals ,Antineoplastic Agents ,Cell Growth Processes ,Disulfides ,Organ Size ,Spleen - Abstract
Enhanced garlic (Allium sativum) consumption is closely related to reduced cancer incidence, as shown in epidemiological studies. Diallyl disulfide (DADS), a component of garlic, inhibits the proliferation of human blood, colon, lung and skin cancer cells. Although DADS had been reported to induce apoptosis in human leukemia HL-60 cells, there are no reports regarding whether or not it affects leukemia cells in vivo. Therefore, the present study is focused on the in vivo effects of DADS on WEHI-3 leukemia cells. The effects of DADS on murine WEHI-3 cells were initially examined, and the results indicated that DADS induced cytotoxicity and that this effect was dose-dependent. The effects of DADS on WEHI-3 in BALBIc mice were also examined, and the results indicated that DADS decreased the percentage of MAC-3 marker, indicating that differentiation of the precursor of macrophage and T cells was inhibited. The weights of liver and spleen were also measured, and the results indicated that DADS decreased the weight of these organs. An important characteristic of WEHI-3 leukemia is the enlarged spleen in mice after i.p. injection of WEHI-3 cells. Based on pathological examination, the function of DADS was observed in the liver and spleen of mice previously injected with WEHI-3 cells. Apparently, DADS affects WEHI-3 cells both in vitro and in vivo.
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- 2006
50. Crude extract of garlic induced caspase-3 gene expression leading to apoptosis in human colon cancer cells
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Chin-Cheng, Su, Guang-Wei, Chen, Tzu-Wei, Tan, Jaung-Gung, Lin, and Jing-Gung, Chung
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Caspase 3 ,Plant Extracts ,Blotting, Western ,Nucleic Acid Hybridization ,Apoptosis ,Adenocarcinoma ,Flow Cytometry ,Gene Expression Regulation, Enzymologic ,Membrane Potentials ,Mitochondria ,Gene Expression Regulation, Neoplastic ,Caspases ,Colonic Neoplasms ,Tumor Cells, Cultured ,Humans ,Garlic ,Oligonucleotide Array Sequence Analysis - Abstract
Garlic (Allium sativum) is a popular spice, a remedy for a variety of ailments and is also known for its medicinal uses as an antibiotic, antithrombotic and antineoplastic agent. Epidemiological and animal studies have shown that garlic consumption reduces the incidence of cancer e.g. in the stomach, colon, breast and cervix. The aim of this study was to investigate whether garlic extract has any influence on caspase-3 activity and gene expression and on the signal induction of apoptosis in vitro. As an assay system, the flow cytometry assay, Western blotting and cDNA microarray were applied in human colon cancer colo 205 cells. Our results indicated that garlic extract, when administered to the colo 205 cell cultures, reduced the percetange of viable cells, induced apoptosis, increased the levels of Bax, cytochrome c and caspase-3, but decreased the level of Bcl-2. The results also showed that raw extract of garlic decreased the mitochondrial membrane potential and increased the caspase-3 activity and gene expression. We conclude that crude extract of garlic can induce apoptosis in colo 205 cells through caspase -3 activity, by means of a mitochondrial-dependent mechanism.
- Published
- 2006
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