AIM:To explore the potential of β-elemene as a radiosensitizer for gastric cancer cells and the underlying mechanisms.METHODS:SGC7901,MKN45,MKN28,N87,and AGS human gastric cancer cell lines were used to screen for ra...AIM:To explore the potential of β-elemene as a radiosensitizer for gastric cancer cells and the underlying mechanisms.METHODS:SGC7901,MKN45,MKN28,N87,and AGS human gastric cancer cell lines were used to screen for radioresistant gastric cancer cell lines. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium(MTT) assay was used to determine the effects of β-elemene and IPA-3 on cell viability in MKN45 and SGC7901 gastric cancer cell lines. A clonogenic survival assay and annexin V-FITC/PI apoptosis detection assay were used to evaluate cellular radiosensitivity and radiation-induced cell death,respectively. A proteomic method,isobaric tags for relative and absolute quantitation(i TRAQ),was employed to screen the proteins regulated by β-elemene pretreatment prior to ionizing radiation(IR) in SGC7901 gastric cancer cell line. IPA-3 was used as a specific small molecule inhibitor of p21-activated protein kinase 1(Pak1) to target Pak1 signaling. Protein levels of PAK1IP1(p21-activated protein kinase-interacting protein 1),total Pak1(t-Pak1),phospho-Pak1(T423),phospho-ERK1/2( Thr202/Tyr204),and cleaved caspase-3(17 k Da) were assessed by western blotting.RESULTS:MKN45 and SGC7901 gastric cancer cell lines were relatively more resistant to IR. β-elemene pretreatment decreased clonogenic survival following IR in MKN45 and SGC7901 gastric cancer cell lines. Additionally,β-elemene pretreatment prior to IR increased radiation-induced cell death compared with IR alone in MKN45(10.4% ± 0.9% vs 34.8% ± 2.8%,P < 0.05) and SGC7901(11.6% ± 0.9% vs 46.7% ± 5.2%,P < 0.05) human gastric cancer cell lines,respectively,consistent with the level of cleaved caspase-3(17 k Da). Through i TRAQ analysis and western blot validation,we found that β-elemene upregulated PAK1IP1 and downregulated phospho-Pak1(T423) and phosphoERK1/2 in SGC7901 gastric cancer cells. IR increased the level of phospho-Pak1(T423). Pretreatment with β-elemene decreased radiation-induced Pak1 and ERK1/2 phosphorylation. Inhibition of Pak1 using IPA-3 dec展开更多
The Lijiang 2.4-meter Telescope(LJT), the largest common-purpose optical telescope in China,has been available to the worldwide astronomical community since 2008. It is located at the Gaomeigu site,Lijiang Observatory...The Lijiang 2.4-meter Telescope(LJT), the largest common-purpose optical telescope in China,has been available to the worldwide astronomical community since 2008. It is located at the Gaomeigu site,Lijiang Observatory(LJO), in the southwest of China. The site has very good observational conditions.During its 10-year operation, several instruments have been equipped on the LJT. Astronomers can perform both photometric and spectral observations. The main scientific goals of LJT include recording photometric and spectral evolution of supernovae, reverberation mapping of active galactic nuclei, investigating the physical properties of binary stars and near-earth objects(comets and asteroids), and identification of exoplanets and all kinds of transients. Until now, the masses of 41 high accretion rate black holes have been measured, and more than 168 supernovae have been identified by the LJT. More than 190 papers related to the LJT have been published. In this paper, the general observation conditions of the Gaomeigu site is introduced at first. Then, the structure of the LJT is described in detail, including the optical, mechanical, motion and control system. The specification of all the instruments and some detailed parameters of the YFOSC is also presented. Finally, some important scientific results and future expectations are summarized.展开更多
“A Craftsman Must Sharpen His Tools to Do His Job,”said Confucius.Nuclear detection and readout techniques are the foundation of particle physics,nuclear physics,and particle astrophysics to reveal the nature of the...“A Craftsman Must Sharpen His Tools to Do His Job,”said Confucius.Nuclear detection and readout techniques are the foundation of particle physics,nuclear physics,and particle astrophysics to reveal the nature of the universe.Also,they are being increasingly used in other disciplines like nuclear power generation,life sciences,environmental sciences,medical sciences,etc.The article reviews the short history,recent development,and trend of nuclear detection and readout techniques,covering Semiconductor Detector,Gaseous Detector,Scintillation Detector,Cherenkov Detector,Transition Radiation Detector,and Readout Techniques.By explaining the principle and using examples,we hope to help the interested reader underst and this research field and bring exciting information to the community.展开更多
A prototype beam monitor was designed to provide tracking information for heavy-ion projectiles for the cool storage ring(CSR)external target experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL).High gr...A prototype beam monitor was designed to provide tracking information for heavy-ion projectiles for the cool storage ring(CSR)external target experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL).High granularity and direct charge sensing are the main features of this device.It measures the beam position in a two-dimensional(2D)plane transverse to the beam direction on an event-by-event basis.The current design consists of two field cages inside a single vessel that operates independently and has electrical drift fields in orthogonal directions.Preliminary tests of the prototype were performed using a^(241)Am a source.The results show that a spatial resolution of less than 40μm and a time resolution of less than 600 ns can be achieved.展开更多
基金Supported by National Nature Science Foundation of China,No.81172357
文摘AIM:To explore the potential of β-elemene as a radiosensitizer for gastric cancer cells and the underlying mechanisms.METHODS:SGC7901,MKN45,MKN28,N87,and AGS human gastric cancer cell lines were used to screen for radioresistant gastric cancer cell lines. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium(MTT) assay was used to determine the effects of β-elemene and IPA-3 on cell viability in MKN45 and SGC7901 gastric cancer cell lines. A clonogenic survival assay and annexin V-FITC/PI apoptosis detection assay were used to evaluate cellular radiosensitivity and radiation-induced cell death,respectively. A proteomic method,isobaric tags for relative and absolute quantitation(i TRAQ),was employed to screen the proteins regulated by β-elemene pretreatment prior to ionizing radiation(IR) in SGC7901 gastric cancer cell line. IPA-3 was used as a specific small molecule inhibitor of p21-activated protein kinase 1(Pak1) to target Pak1 signaling. Protein levels of PAK1IP1(p21-activated protein kinase-interacting protein 1),total Pak1(t-Pak1),phospho-Pak1(T423),phospho-ERK1/2( Thr202/Tyr204),and cleaved caspase-3(17 k Da) were assessed by western blotting.RESULTS:MKN45 and SGC7901 gastric cancer cell lines were relatively more resistant to IR. β-elemene pretreatment decreased clonogenic survival following IR in MKN45 and SGC7901 gastric cancer cell lines. Additionally,β-elemene pretreatment prior to IR increased radiation-induced cell death compared with IR alone in MKN45(10.4% ± 0.9% vs 34.8% ± 2.8%,P < 0.05) and SGC7901(11.6% ± 0.9% vs 46.7% ± 5.2%,P < 0.05) human gastric cancer cell lines,respectively,consistent with the level of cleaved caspase-3(17 k Da). Through i TRAQ analysis and western blot validation,we found that β-elemene upregulated PAK1IP1 and downregulated phospho-Pak1(T423) and phosphoERK1/2 in SGC7901 gastric cancer cells. IR increased the level of phospho-Pak1(T423). Pretreatment with β-elemene decreased radiation-induced Pak1 and ERK1/2 phosphorylation. Inhibition of Pak1 using IPA-3 dec
基金supported by the Joint Research Fund in Astronomy (U1631127, U1631129 and U1831204) under cooperative agreement between the National Natural Science Foundation of China (NSFC) and Chinese Academy of Sciences (CAS)the National Natural Science Foundation of China (NSFC) (11473068, 11603072 and 11573067)+1 种基金the National Key R&D Program of China (2018YFA0404603)supported by the Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences (CAS)
文摘The Lijiang 2.4-meter Telescope(LJT), the largest common-purpose optical telescope in China,has been available to the worldwide astronomical community since 2008. It is located at the Gaomeigu site,Lijiang Observatory(LJO), in the southwest of China. The site has very good observational conditions.During its 10-year operation, several instruments have been equipped on the LJT. Astronomers can perform both photometric and spectral observations. The main scientific goals of LJT include recording photometric and spectral evolution of supernovae, reverberation mapping of active galactic nuclei, investigating the physical properties of binary stars and near-earth objects(comets and asteroids), and identification of exoplanets and all kinds of transients. Until now, the masses of 41 high accretion rate black holes have been measured, and more than 168 supernovae have been identified by the LJT. More than 190 papers related to the LJT have been published. In this paper, the general observation conditions of the Gaomeigu site is introduced at first. Then, the structure of the LJT is described in detail, including the optical, mechanical, motion and control system. The specification of all the instruments and some detailed parameters of the YFOSC is also presented. Finally, some important scientific results and future expectations are summarized.
基金supported by the National Natural Science Foundation of China(No.12222512,U2032209,12075045,12335011,1875097,11975257,62074146,11975115,12205374,12305210,11975292,12005276,12005278,12375193,12227805,12235012,12375191,12005279)the National Key Research and Development Program of China(2021YFA1601300)+13 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB34000000)the CAS Pioneer Hundred Talent Programthe CAS“Light of West China”Programthe Natural Science Foundation of Liaoning Province(No.101300261)the Dalian Science and Technology Innovation Fund(2023JJ12GX013)the Special Projects of the Central Government in Guidance of Local Science and Technology Development(Research and development of three-dimensional prospecting technology based on Cosmic-ray muons)(YDZX20216200001297)the Science and Technology Planning Project of Gansu(20JR10RA645)the Lanzhou University Talent Cooperation Research Funds sponsored by both Lanzhou City(561121203)the Gansu provincial science and technology plan projects for talents(054000029)the Beijing Natural Science Foundation(No.1232033)the Beijing Hope Run Special Fund of Cancer Foundation of China(No.LC2021B23)the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030008)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(No.GJJSTD20210009)the Youth Innovation Promotion Association CAS(2021450)。
文摘“A Craftsman Must Sharpen His Tools to Do His Job,”said Confucius.Nuclear detection and readout techniques are the foundation of particle physics,nuclear physics,and particle astrophysics to reveal the nature of the universe.Also,they are being increasingly used in other disciplines like nuclear power generation,life sciences,environmental sciences,medical sciences,etc.The article reviews the short history,recent development,and trend of nuclear detection and readout techniques,covering Semiconductor Detector,Gaseous Detector,Scintillation Detector,Cherenkov Detector,Transition Radiation Detector,and Readout Techniques.By explaining the principle and using examples,we hope to help the interested reader underst and this research field and bring exciting information to the community.
基金supported by the National Natural Science Foundation of China (Nos. 11927901, U2032209, 12005046)
文摘A prototype beam monitor was designed to provide tracking information for heavy-ion projectiles for the cool storage ring(CSR)external target experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL).High granularity and direct charge sensing are the main features of this device.It measures the beam position in a two-dimensional(2D)plane transverse to the beam direction on an event-by-event basis.The current design consists of two field cages inside a single vessel that operates independently and has electrical drift fields in orthogonal directions.Preliminary tests of the prototype were performed using a^(241)Am a source.The results show that a spatial resolution of less than 40μm and a time resolution of less than 600 ns can be achieved.