BACKGROUND Centipedes have been used to treat tumors for hundreds of years in China.However,current studies focus on antimicrobial and anticoagulation agents rather than tumors.The molecular identities of antihepatoma...BACKGROUND Centipedes have been used to treat tumors for hundreds of years in China.However,current studies focus on antimicrobial and anticoagulation agents rather than tumors.The molecular identities of antihepatoma bioactive components in centipedes have not yet been extensively investigated.It is a challenge to isolate and characterize the effective components of centipedes due to limited peptide purification technologies for animal-derived medicines.AIM To purify,characterize,and synthesize the bioactive components with the strongest antihepatoma activity from centipedes and determine the antihepatoma mechanism.METHODS An antihepatoma peptide(scolopentide)was isolated and identified from the centipede scolopendra subspinipes mutilans using a combination of enzymatic hydrolysis,a Sephadex G-25 column,and two steps of high-performance liquid chromatography(HPLC).Additionally,the CCK8 assay was used to select the extracted fraction with the strongest antihepatoma activity.The molecular weight of the extracted scolopentide was characterized by quadrupole time of flight mass spectrometry(QTOF MS),and the sequence was matched by using the Mascot search engine.Based on the sequence and molecular weight,scolopentide was synthesized using solid-phase peptide synthesis methods.The synthetic scolopentide was confirmed by MS and HPLC.The antineoplastic effect of extracted scolopentide was confirmed by CCK8 assay and morphological changes again in vitro.The antihepatoma effect of synthetic scolopentide was assessed by the CCK8 assay and Hoechst staining in vitro and tumor volume and tumor weight in vivo.In the tumor xenograft experiments,qualified model mice(male 5-week-old BALB/c nude mice)were randomly divided into 2 groups(n=6):The scolopentide group(0.15 mL/d,via intraperitoneal injection of synthetic scolopentide,500 mg/kg/d)and the vehicle group(0.15 mL/d,via intraperitoneal injection of normal saline).The mice were euthanized by cervical dislocation after 14 d of continuous treatment.Mechanistically,flow cytometry was conducted to evaluate the apoptosis rate of HepG2 cells after treatment with extracted scolopentide in vitro.A Hoechst staining assay was also used to observe apoptosis in HepG2 cells after treatment with synthetic scolopentide in vitro.CCK8 assays and morphological changes were used to compare the cytotoxicity of synthetic scolopentide to liver cancer cells and normal liver cells in vitro.Molecular docking was performed to clarify whether scolopentide tightly bound to death receptor 4(DR4)and DR5.qRT-PCR was used to measure the mRNA expression of DR4,DR5,fas-associated death domain protein(FADD),Caspase-8,Caspase-3,cytochrome c(Cyto-C),B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),x-chromosome linked inhibitor-of-apoptosis protein and Cellular fas-associated death domain-like interleukin-1βconverting enzyme inhibitory protein in hepatocarcinoma subcutaneous xenograft tumors from mice.Western blot assays were used to measure the protein expression of DR4,DR5,FADD,Caspase-8,Caspase-3,and Cyto-C in the tumor tissues.The reactive oxygen species(ROS)of tumor tissues were tested.RESULTS In the process of purification,characterization and synthesis of scolopentide,the optimal enzymatic hydrolysis conditions(extract ratio:5.86%,IC_(50):0.310 mg/mL)were as follows:Trypsin at 0.1 g(300 U/g,centipede-trypsin ratio of 20:1),enzymolysis temperature of 46°C,and enzymolysis time of 4 h,which was superior to freeze-thawing with liquid nitrogen(IC_(50):3.07 mg/mL).A peptide with the strongest antihepatoma activity(scolopentide)was further purified through a Sephadex G-25 column(obtained A2)and two steps of HPLC(obtained B5 and C3).The molecular weight of the extracted scolopentide was 1018.997 Da,and the peptide sequence was RAQNHYCK,as characterized by QTOF MS and Mascot.Scolopentide was synthesized in vitro with a qualified molecular weight(1018.8 Da)and purity(98.014%),which was characterized by MS and HPLC.Extracted scolopentide still had an antineoplastic effect in vitro,which inhibited the proliferation of Eca-109(IC_(50):76.27μg/mL),HepG2(IC_(50):22.06μg/mL),and A549(IC_(50):35.13μg/mL)cells,especially HepG2 cells.Synthetic scolopentide inhibited the proliferation of HepG2 cells(treated 6,12,and 24 h)in a concentration-dependent manner in vitro,and the inhibitory effects were the strongest at 12 h(IC_(50):208.11μg/mL).Synthetic scolopentide also inhibited the tumor volume(Vehicle vs Scolopentide,P=0.0003)and weight(Vehicle vs Scolopentide,P=0.0022)in the tumor xenograft experiment.Mechanistically,flow cytometry suggested that the apoptosis ratios of HepG2 cells after treatment with extracted scolopentide were 5.01%(0μg/mL),12.13%(10μg/mL),16.52%(20μg/mL),and 23.20%(40μg/mL).Hoechst staining revealed apoptosis in HepG2 cells after treatment with synthetic scolopentide in vitro.The CCK8 assay and morphological changes indicated that synthetic scolopentide was cytotoxic and was significantly stronger in HepG2 cells than in L02 cells.Molecular docking suggested that scolopentide tightly bound to DR4 and DR5,and the binding free energies were-10.4 kcal/mol and-7.1 kcal/mol,respectively.In subcutaneous xenograft tumors from mice,quantitative real-time polymerase chain reaction and western blotting suggested that scolopentide activated DR4 and DR5 and induced apoptosis in SMMC-7721 Liver cancer cells by promoting the expression of FADD,caspase-8 and caspase-3 through a mitochondria-independent pathway.CONCLUSION Scolopentide,an antihepatoma peptide purified from centipedes,may inspire new antihepatoma agents.Scolopentide activates DR4 and DR5 and induces apoptosis in liver cancer cells through a mitochondria-independent pathway.展开更多
Nucleophosmin/B23 (NPM) is a universally expressed nucleolar phosphoprotein that participates in proliferation, apoptosis, ribosome assembly, and centrosome duplication; however, the role of NPM in cell cycle regulati...Nucleophosmin/B23 (NPM) is a universally expressed nucleolar phosphoprotein that participates in proliferation, apoptosis, ribosome assembly, and centrosome duplication; however, the role of NPM in cell cycle regulation is not well characterized. We investigated the mechanism by which NPM is involved in cell cycle regulation. NPM was knocked down using siRNA in HepG2 hepatoblastoma cells. NPM translocation following actinomycin D (ActD) treatment was investigated using immunofluorescent staining. Expression of NPM and other factors involved in cell cycle regulation was examined by Western blotting. Cell cycle distribution was measured using flow cytometry to detect 5-ethynyl-2′-deoxyuridine (EdU) incorporation. Cell proliferation was quantified by the MTT assay. Knockdown of NPM increased the percentage of HepG2 cells in S phase and led to decreased expression of P53 and P21Cip1/WAF1. S-phase arrest in HepG2 cells was significantly enhanced by ActD treatment. Furthermore, knockdown of NPM abrogated ActD-induced G2/M phase cell cycle arrest. Taken together, these data demonstrate that inhibition of NPM has a significant effect on the cell cycle.展开更多
Last year,the doubling of the A-share market was unmatched in global capital markets.Fu- eled by appreciation of the RMB,sectors like finance and real estate as well newly revitalized areas like non- ferrous metals,th...Last year,the doubling of the A-share market was unmatched in global capital markets.Fu- eled by appreciation of the RMB,sectors like finance and real estate as well newly revitalized areas like non- ferrous metals,the steel and chemical industries,drove market growth,creat- ing many millionaires in the process. In terms of pure performance,all of the 13 sectors classified by the CSRC had strong performance with growth展开更多
The National Development and Reform Commission of China (NDRC) released on August 27 a report on the first-half operation and the second-half expectation of the coal industry.The coal industry is predicted to have a c...The National Development and Reform Commission of China (NDRC) released on August 27 a report on the first-half operation and the second-half expectation of the coal industry.The coal industry is predicted to have a consecutive balance of sup- ply and demand this year with a less strained supply in the second half.展开更多
According to customs statistics, Chinese trade imports and exports totaled US$ 1,759.32 billion from January to October this year,representing an increase of 23.5 percent over the same period last year, and nearly equ...According to customs statistics, Chinese trade imports and exports totaled US$ 1,759.32 billion from January to October this year,representing an increase of 23.5 percent over the same period last year, and nearly equal to the total amount of imports and exports from all of last year.Exports were US$ 985.84展开更多
The'three most-wanted'goods,those seen as a symbol of wealth for Chinese families, has seen an evolution from specific products to general services with average values that first increased from RMB 100 to RMB ...The'three most-wanted'goods,those seen as a symbol of wealth for Chinese families, has seen an evolution from specific products to general services with average values that first increased from RMB 100 to RMB 10,000,and now have moved upwards of RMB 100,000.While this measure is not the most scientific,it reflects the great changes China has undergone,and also mirrors the transformation of Chinese lifestyle.展开更多
Aseries of events that occurred in October 2007,are rewrit- ing the history of China's en- ergy industry:November 3 an Energy Law Committee asked the public for suggestions on improvements;forty top experts came t...Aseries of events that occurred in October 2007,are rewrit- ing the history of China's en- ergy industry:November 3 an Energy Law Committee asked the public for suggestions on improvements;forty top experts came together to form the National Energy Expert Advisory Committee on November 6;and the National Oil Reserve Center(NORC)展开更多
The Office of the National Ener- gy Leading Group announced a draft of the upcoming energy law on December 3,2007,in an effort to collect feedback from the public and the media through the Internet up to the 1 of Febr...The Office of the National Ener- gy Leading Group announced a draft of the upcoming energy law on December 3,2007,in an effort to collect feedback from the public and the media through the Internet up to the 1 of February 2008.This marks the first time that the draft of a new energy law has been released to the public since research and study work began in 2006;the event also symbolizes a new phase for energy legislation.展开更多
2007 was an unusual year for China's stock market,as the in- dex climbed from 2675 points up to 6124 by the end of the year,setting new records again and again through- out 2007.What will happen to the stock marke...2007 was an unusual year for China's stock market,as the in- dex climbed from 2675 points up to 6124 by the end of the year,setting new records again and again through- out 2007.What will happen to the stock market in the coming 2008?Let's have a look at some of the main factors展开更多
In recent years,China's public finance put social construction high on the agenda and attaches more importance on livelihood insurance and improvement. The 2003-2007 public financial expendi- ture reflects a fact ...In recent years,China's public finance put social construction high on the agenda and attaches more importance on livelihood insurance and improvement. The 2003-2007 public financial expendi- ture reflects a fact that the government展开更多
The rapid growth of China's trade surplus is a reflection of its industrial advancement and growing competitiveness. In the last 5 years,China's foreign trade has been on the track of rapid development:import ...The rapid growth of China's trade surplus is a reflection of its industrial advancement and growing competitiveness. In the last 5 years,China's foreign trade has been on the track of rapid development:import and export volume increased from US$620.8 bil- lion in 2002 to US$2173.8 billion in 2007, boasting an annual growth rate of 28.5 percent;a rate which has marked the lon- gest period,fastest and most stable growth rate since the implementation of the reform and opening-up policy.China's economic rank in the world rose from 6th in 2002 to 3rd last year,and it currently ranks second in the world in terms of exports.展开更多
2007 was an unusual year for China's stock market, as the index climbed from 2675 points up to 6124 by the end of the year, setting new records again and again throughout 2007. What will happen to the stock ma... 2007 was an unusual year for China's stock market, as the index climbed from 2675 points up to 6124 by the end of the year, setting new records again and again throughout 2007. What will happen to the stock market in the coming 2008? Let's havea look at some of the main factors that will influence the stock market this year, perhaps we can find out if 2008 will be another memorable year full of surprises.……展开更多
As a serious snowstorm hit most of southern China,some heart-warming news on the capital markets came from the National Work Conference on Securities and Futures Supervision held on Janu- ary 16th and 17th.According t...As a serious snowstorm hit most of southern China,some heart-warming news on the capital markets came from the National Work Conference on Securities and Futures Supervision held on Janu- ary 16th and 17th.According to Shang Fulin,Chairman of the China Securi- ties Regulatory Commission(CSRC), securities regulators hope to open a new stock market in the first half of the year aimed at high-growth enterprises.'The Growth Enterprise Board has a chance to be launched after China's展开更多
As one of the most important and far-reaching focal points in people's lives,the Golden-Week holiday,is much more than a year 21-day vacation.How did the Golden Week take shape over the past few years,gradually at...As one of the most important and far-reaching focal points in people's lives,the Golden-Week holiday,is much more than a year 21-day vacation.How did the Golden Week take shape over the past few years,gradually attracting people's attention,and hav- ing an increasingly important impact in China each year?展开更多
As nearly everyone knows already, the state is going to rearrange the schedule of legal holidays.The four traditional Chinese festivals,inluding Mid-Autumn Day,Dragon Boat Festival, Tomb-Sweeping Day and Spring Festiv...As nearly everyone knows already, the state is going to rearrange the schedule of legal holidays.The four traditional Chinese festivals,inluding Mid-Autumn Day,Dragon Boat Festival, Tomb-Sweeping Day and Spring Festival Eve,will be made into legal holidays.As for the Golden Week system,should it be continued or canceled?The answer to this question can vary depending on who you talk to,public opinion has formed a gen-展开更多
Accompanied by the maturing of China-EU political relations beginning in the 1990s,China- EU economic and trade relations have de- veloped significantly each year.Now the EU has become China's largest trading part...Accompanied by the maturing of China-EU political relations beginning in the 1990s,China- EU economic and trade relations have de- veloped significantly each year.Now the EU has become China's largest trading partner,as well as China's largest technol- ogy provider and fourth largest invest-展开更多
基金Supported by the National Natural Science Foundation of China,No.U20A20408 and No.82074450Natural Science Foundation of Hunan Province,No.2020JJ4066 and No.2021JJ40405+1 种基金Key scientific research project of Hunan Education Department,No.21A0243Key project of academician workstation guidance project,No.21YSZQ007.
文摘BACKGROUND Centipedes have been used to treat tumors for hundreds of years in China.However,current studies focus on antimicrobial and anticoagulation agents rather than tumors.The molecular identities of antihepatoma bioactive components in centipedes have not yet been extensively investigated.It is a challenge to isolate and characterize the effective components of centipedes due to limited peptide purification technologies for animal-derived medicines.AIM To purify,characterize,and synthesize the bioactive components with the strongest antihepatoma activity from centipedes and determine the antihepatoma mechanism.METHODS An antihepatoma peptide(scolopentide)was isolated and identified from the centipede scolopendra subspinipes mutilans using a combination of enzymatic hydrolysis,a Sephadex G-25 column,and two steps of high-performance liquid chromatography(HPLC).Additionally,the CCK8 assay was used to select the extracted fraction with the strongest antihepatoma activity.The molecular weight of the extracted scolopentide was characterized by quadrupole time of flight mass spectrometry(QTOF MS),and the sequence was matched by using the Mascot search engine.Based on the sequence and molecular weight,scolopentide was synthesized using solid-phase peptide synthesis methods.The synthetic scolopentide was confirmed by MS and HPLC.The antineoplastic effect of extracted scolopentide was confirmed by CCK8 assay and morphological changes again in vitro.The antihepatoma effect of synthetic scolopentide was assessed by the CCK8 assay and Hoechst staining in vitro and tumor volume and tumor weight in vivo.In the tumor xenograft experiments,qualified model mice(male 5-week-old BALB/c nude mice)were randomly divided into 2 groups(n=6):The scolopentide group(0.15 mL/d,via intraperitoneal injection of synthetic scolopentide,500 mg/kg/d)and the vehicle group(0.15 mL/d,via intraperitoneal injection of normal saline).The mice were euthanized by cervical dislocation after 14 d of continuous treatment.Mechanistically,flow cytometry was conducted to evaluate the apoptosis rate of HepG2 cells after treatment with extracted scolopentide in vitro.A Hoechst staining assay was also used to observe apoptosis in HepG2 cells after treatment with synthetic scolopentide in vitro.CCK8 assays and morphological changes were used to compare the cytotoxicity of synthetic scolopentide to liver cancer cells and normal liver cells in vitro.Molecular docking was performed to clarify whether scolopentide tightly bound to death receptor 4(DR4)and DR5.qRT-PCR was used to measure the mRNA expression of DR4,DR5,fas-associated death domain protein(FADD),Caspase-8,Caspase-3,cytochrome c(Cyto-C),B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),x-chromosome linked inhibitor-of-apoptosis protein and Cellular fas-associated death domain-like interleukin-1βconverting enzyme inhibitory protein in hepatocarcinoma subcutaneous xenograft tumors from mice.Western blot assays were used to measure the protein expression of DR4,DR5,FADD,Caspase-8,Caspase-3,and Cyto-C in the tumor tissues.The reactive oxygen species(ROS)of tumor tissues were tested.RESULTS In the process of purification,characterization and synthesis of scolopentide,the optimal enzymatic hydrolysis conditions(extract ratio:5.86%,IC_(50):0.310 mg/mL)were as follows:Trypsin at 0.1 g(300 U/g,centipede-trypsin ratio of 20:1),enzymolysis temperature of 46°C,and enzymolysis time of 4 h,which was superior to freeze-thawing with liquid nitrogen(IC_(50):3.07 mg/mL).A peptide with the strongest antihepatoma activity(scolopentide)was further purified through a Sephadex G-25 column(obtained A2)and two steps of HPLC(obtained B5 and C3).The molecular weight of the extracted scolopentide was 1018.997 Da,and the peptide sequence was RAQNHYCK,as characterized by QTOF MS and Mascot.Scolopentide was synthesized in vitro with a qualified molecular weight(1018.8 Da)and purity(98.014%),which was characterized by MS and HPLC.Extracted scolopentide still had an antineoplastic effect in vitro,which inhibited the proliferation of Eca-109(IC_(50):76.27μg/mL),HepG2(IC_(50):22.06μg/mL),and A549(IC_(50):35.13μg/mL)cells,especially HepG2 cells.Synthetic scolopentide inhibited the proliferation of HepG2 cells(treated 6,12,and 24 h)in a concentration-dependent manner in vitro,and the inhibitory effects were the strongest at 12 h(IC_(50):208.11μg/mL).Synthetic scolopentide also inhibited the tumor volume(Vehicle vs Scolopentide,P=0.0003)and weight(Vehicle vs Scolopentide,P=0.0022)in the tumor xenograft experiment.Mechanistically,flow cytometry suggested that the apoptosis ratios of HepG2 cells after treatment with extracted scolopentide were 5.01%(0μg/mL),12.13%(10μg/mL),16.52%(20μg/mL),and 23.20%(40μg/mL).Hoechst staining revealed apoptosis in HepG2 cells after treatment with synthetic scolopentide in vitro.The CCK8 assay and morphological changes indicated that synthetic scolopentide was cytotoxic and was significantly stronger in HepG2 cells than in L02 cells.Molecular docking suggested that scolopentide tightly bound to DR4 and DR5,and the binding free energies were-10.4 kcal/mol and-7.1 kcal/mol,respectively.In subcutaneous xenograft tumors from mice,quantitative real-time polymerase chain reaction and western blotting suggested that scolopentide activated DR4 and DR5 and induced apoptosis in SMMC-7721 Liver cancer cells by promoting the expression of FADD,caspase-8 and caspase-3 through a mitochondria-independent pathway.CONCLUSION Scolopentide,an antihepatoma peptide purified from centipedes,may inspire new antihepatoma agents.Scolopentide activates DR4 and DR5 and induces apoptosis in liver cancer cells through a mitochondria-independent pathway.
基金supported by grants from theNational Natural Science Foundation of China (No.81172345 and No. 30973506)the National High Technology Research and Development Program of China (863 Program) (2006AA02A404 to Y-X.Z.)
文摘Nucleophosmin/B23 (NPM) is a universally expressed nucleolar phosphoprotein that participates in proliferation, apoptosis, ribosome assembly, and centrosome duplication; however, the role of NPM in cell cycle regulation is not well characterized. We investigated the mechanism by which NPM is involved in cell cycle regulation. NPM was knocked down using siRNA in HepG2 hepatoblastoma cells. NPM translocation following actinomycin D (ActD) treatment was investigated using immunofluorescent staining. Expression of NPM and other factors involved in cell cycle regulation was examined by Western blotting. Cell cycle distribution was measured using flow cytometry to detect 5-ethynyl-2′-deoxyuridine (EdU) incorporation. Cell proliferation was quantified by the MTT assay. Knockdown of NPM increased the percentage of HepG2 cells in S phase and led to decreased expression of P53 and P21Cip1/WAF1. S-phase arrest in HepG2 cells was significantly enhanced by ActD treatment. Furthermore, knockdown of NPM abrogated ActD-induced G2/M phase cell cycle arrest. Taken together, these data demonstrate that inhibition of NPM has a significant effect on the cell cycle.
文摘Last year,the doubling of the A-share market was unmatched in global capital markets.Fu- eled by appreciation of the RMB,sectors like finance and real estate as well newly revitalized areas like non- ferrous metals,the steel and chemical industries,drove market growth,creat- ing many millionaires in the process. In terms of pure performance,all of the 13 sectors classified by the CSRC had strong performance with growth
文摘The National Development and Reform Commission of China (NDRC) released on August 27 a report on the first-half operation and the second-half expectation of the coal industry.The coal industry is predicted to have a consecutive balance of sup- ply and demand this year with a less strained supply in the second half.
文摘According to customs statistics, Chinese trade imports and exports totaled US$ 1,759.32 billion from January to October this year,representing an increase of 23.5 percent over the same period last year, and nearly equal to the total amount of imports and exports from all of last year.Exports were US$ 985.84
文摘The'three most-wanted'goods,those seen as a symbol of wealth for Chinese families, has seen an evolution from specific products to general services with average values that first increased from RMB 100 to RMB 10,000,and now have moved upwards of RMB 100,000.While this measure is not the most scientific,it reflects the great changes China has undergone,and also mirrors the transformation of Chinese lifestyle.
文摘Aseries of events that occurred in October 2007,are rewrit- ing the history of China's en- ergy industry:November 3 an Energy Law Committee asked the public for suggestions on improvements;forty top experts came together to form the National Energy Expert Advisory Committee on November 6;and the National Oil Reserve Center(NORC)
文摘The Office of the National Ener- gy Leading Group announced a draft of the upcoming energy law on December 3,2007,in an effort to collect feedback from the public and the media through the Internet up to the 1 of February 2008.This marks the first time that the draft of a new energy law has been released to the public since research and study work began in 2006;the event also symbolizes a new phase for energy legislation.
文摘2007 was an unusual year for China's stock market,as the in- dex climbed from 2675 points up to 6124 by the end of the year,setting new records again and again through- out 2007.What will happen to the stock market in the coming 2008?Let's have a look at some of the main factors
文摘In recent years,China's public finance put social construction high on the agenda and attaches more importance on livelihood insurance and improvement. The 2003-2007 public financial expendi- ture reflects a fact that the government
文摘The rapid growth of China's trade surplus is a reflection of its industrial advancement and growing competitiveness. In the last 5 years,China's foreign trade has been on the track of rapid development:import and export volume increased from US$620.8 bil- lion in 2002 to US$2173.8 billion in 2007, boasting an annual growth rate of 28.5 percent;a rate which has marked the lon- gest period,fastest and most stable growth rate since the implementation of the reform and opening-up policy.China's economic rank in the world rose from 6th in 2002 to 3rd last year,and it currently ranks second in the world in terms of exports.
文摘 2007 was an unusual year for China's stock market, as the index climbed from 2675 points up to 6124 by the end of the year, setting new records again and again throughout 2007. What will happen to the stock market in the coming 2008? Let's havea look at some of the main factors that will influence the stock market this year, perhaps we can find out if 2008 will be another memorable year full of surprises.……
文摘As a serious snowstorm hit most of southern China,some heart-warming news on the capital markets came from the National Work Conference on Securities and Futures Supervision held on Janu- ary 16th and 17th.According to Shang Fulin,Chairman of the China Securi- ties Regulatory Commission(CSRC), securities regulators hope to open a new stock market in the first half of the year aimed at high-growth enterprises.'The Growth Enterprise Board has a chance to be launched after China's
文摘As one of the most important and far-reaching focal points in people's lives,the Golden-Week holiday,is much more than a year 21-day vacation.How did the Golden Week take shape over the past few years,gradually attracting people's attention,and hav- ing an increasingly important impact in China each year?
文摘As nearly everyone knows already, the state is going to rearrange the schedule of legal holidays.The four traditional Chinese festivals,inluding Mid-Autumn Day,Dragon Boat Festival, Tomb-Sweeping Day and Spring Festival Eve,will be made into legal holidays.As for the Golden Week system,should it be continued or canceled?The answer to this question can vary depending on who you talk to,public opinion has formed a gen-
文摘Accompanied by the maturing of China-EU political relations beginning in the 1990s,China- EU economic and trade relations have de- veloped significantly each year.Now the EU has become China's largest trading partner,as well as China's largest technol- ogy provider and fourth largest invest-