The use of carbon-ion radiotherapy(CIRT)is gradually increasing.Owing to the generation of high-energy secondary neutrons during CIRT,its use presents new challenges in radiation protection.Thus,secondary neutron dose...The use of carbon-ion radiotherapy(CIRT)is gradually increasing.Owing to the generation of high-energy secondary neutrons during CIRT,its use presents new challenges in radiation protection.Thus,secondary neutron dose distributions must be explored and evaluated under clinical scenarios based on different treatment configurations.However,neutron dose and energy spectrum measurements are often difficult.This can be primarily attributed to the inherent limitations of most neutron detectors,such as their unsuitability for spectral measurements and inaccurate responses to neutrons with energies above 20 MeV.Numerical calculation methods based on probabilistic statistical theory are fast and convenient for neutron dose evaluation.In this study,external secondary neutron doses at the heavy ion medical machine in Wuwei,which is equipped with a passive beam delivery system,were calculated using the Monte Carlo method.The dependence of neutron doses on various treatment parameters(incident carbon-ion beam energy,spatial location,field size,and spread-out Bragg peak(SOBP)width)was investigated.Furthermore,the feasibility of applying an analytical model to predict the ambient dose equivalent was verified.For the combination involving an energy of 400 MeV=u and SOBP width of 6 cm,the ambient dose equivalent per therapeutic dose(H=D)at the isocenter was 79.87 mSv=Gy:The H=D value decreased rapidly with increasing spatial distance and slightly with increasing aperture size and SOBP width.The H=D values derived from the Monte Carlo simulations were in good agreement with the results reported in the literature.The analytical model could be used to quickly predict the H=D value along the incidence direction of the beam with an error of less than 20%.Thus,our study contributes to the understanding of the relationship between neutron radiation and treatment configuration parameters,which establishes a basis for predicting non-therapeutic radiation doses in CIRT.展开更多
The Er3＋/yb3＋ co-doped phosphate （EYDP） glass waveguides operated at 1539 nm have been manufactured by using the implantation technique of carbon ions under the condition of 6.0 MeV energy and 5.0 × 10^13 ion...The Er3＋/yb3＋ co-doped phosphate （EYDP） glass waveguides operated at 1539 nm have been manufactured by using the implantation technique of carbon ions under the condition of 6.0 MeV energy and 5.0 × 10^13 ions/cm2 fluence in this work. The ion implantation process was computed by means of the stopping and range of ions in matter. The dark-mode spectrum at 1539 nm of the waveguide was recorded by the method of the prism coupling measurement. The microscopic image of the fabricated structure was photographed by an optical microscope. It is the first step for the application of the waveguides on the base of EYDP glasses in optical- integrated photonic devices at near-infrared band.展开更多
BACKGROUND Although the bystander effect and abscopal effect are familiar in medicine,they are relatively rare in clinical practice.Herein,we report the case of a patient who demonstrated an obvious bystander effect a...BACKGROUND Although the bystander effect and abscopal effect are familiar in medicine,they are relatively rare in clinical practice.Herein,we report the case of a patient who demonstrated an obvious bystander effect and abscopal effect response following carbon-ion irradiation for recurrent thymic carcinoma.CASE SUMMARY A 44-year-old female presented with shortness of breath.Eleven years prior,she was diagnosed with athymic tumor located in the anterosuperior mediastinum.She underwent extensive tumor resection,and the postoperative pathologic diagnosis was thymic carcinoma.She was administered 50 Gy/25 Fx of postoperative radiation.In 2019,she was diagnosed with a recurrence of thymic carcinoma,with multiple recurrent nodules and masses in the left thoracic chest and peritoneal cavity,the largest of which was in the diaphragm pleura proximal to the pericardium,with a size of 6.7 cm×5.3 cm×4.8 cm.She received carbonion radiotherapy.After carbon-ion radiotherapy treatment,the treated masses and the untreated masses were observed to have noticeably shrunk on the day of carbon-ion radiotherapy completion and on follow-up imaging.We followed the CARE Guidelines for consensus-based clinical case reporting guideline development and completed the CARE Checklist of information to report this case.CONCLUSION This report is the first of obvious abscopal and bystander effects following carbonion irradiation in a human patient,and further research is needed to better elucidate the mechanisms of bystander and abscopal effects.展开更多
Hepatic epithelioid hemangioendothelioma(HEH)is a rare neoplasm of vascular origin with variable malignant potential.Because most patients with this condition have multiple bilobar lesions,liver transplantation is the...Hepatic epithelioid hemangioendothelioma(HEH)is a rare neoplasm of vascular origin with variable malignant potential.Because most patients with this condition have multiple bilobar lesions,liver transplantation is the standard treatment,and hepatectomy is much less frequently indicated.We describe a case of a 35-yearold woman with unresectable multiple bilobar HEH successfully treated by combination treatment with hepatectomy and carbon-ion radiotherapy.This case is very meaningful since it demonstrated the effectiveness of carbon-ion radiotherapy for HEH and the possibility of expanding the curative treatment options for multiple bilobar hepatic tumors.展开更多
In order to see whether carbon ion (C-ion) beams have a biological advantage over X-rays, studies were designed to examine the effects of C-ion beams on radiosensitivity in X-ray resistant cells. Clinically relevant X...In order to see whether carbon ion (C-ion) beams have a biological advantage over X-rays, studies were designed to examine the effects of C-ion beams on radiosensitivity in X-ray resistant cells. Clinically relevant X-ray resistant SAS-R cells derived from human tongue cancer SAS cells were used. The cells were exposed to X-rays or Spread-Out Bragg peak (SOBP) beam C-ions. Cell survival was measured using a modified high-density survival assay. Cell survival signaling and cell death signaling were analyzed using flow cytometry. The cells were labeled with putative cancer stem cell markers such as CD44 and CD326. SAS-R cells were 1.6 times more radioresistant than SAS cells after exposure to X-rays. Cell survival was similar in each cell line after exposure to C-ion beams. SAS-R cells displayed enhanced cell survival signaling when compared to SAS cells under normal conditions. On the other hand, the phosphorylation of AKT-related proteins decreased and polycaspase activities were enhanced when cells were irradiated with C-ion beams in both cell lines. More CD44 and CD326 positive cells were seen in SAS-R cells than in SAS cells. Moreover, the marker positive cell numbers significantly decreased after exposure to C-ion beams when compared to X-rays at iso-survival doses in SAS-R cells. C-ion beams efficiently induced cell killing in X-ray resistant cells which displayed activated cell survival signaling and contained more numerous cancer stem-like cells.展开更多
Intensity-modulated particle therapy(IMPT)with carbon ions is comparatively susceptible to various uncertainties caused by breathing motion,including range,setup,and target positioning uncertainties.To determine relat...Intensity-modulated particle therapy(IMPT)with carbon ions is comparatively susceptible to various uncertainties caused by breathing motion,including range,setup,and target positioning uncertainties.To determine relative biological effectiveness-weighted dose(RWD)distributions that are resilient to these uncertainties,the reference phase-based four-dimensional(4D)robust optimization(RP-4DRO)and each phase-based 4D robust optimization(EP-4DRO)method in carbon-ion IMPT treatment planning were evaluated and compared.Based on RWD distributions,4DRO methods were compared with 4D conventional optimization using planning target volume(PTV)margins(PTV-based optimization)to assess the effectiveness of the robust optimization methods.Carbon-ion IMPT treatment planning was conducted in a cohort of five lung cancer patients.The results indicated that the EP-4DRO method provided better robustness(P=0.080)and improved plan quality(P=0.225)for the clinical target volume(CTV)in the individual respiratory phase when compared with the PTV-based optimization.Compared with the PTV-based optimization,the RP-4DRO method ensured the robustness(P=0.022)of the dose distributions in the reference breathing phase,albeit with a slight sacrifice of the target coverage(P=0.450).Both 4DRO methods successfully maintained the doses delivered to the organs at risk(OARs)below tolerable levels,which were lower than the doses in the PTV-based optimization(P<0.05).Furthermore,the RP-4DRO method exhibited significantly superior performance when compared with the EP-4DRO method in enhancing overall OAR sparing in either the individual respiratory phase or reference respiratory phase(P<0.05).In general,both 4DRO methods outperformed the PTV-based optimization in terms of OAR sparing and robustness.展开更多
以12个东北粳稻(Oryza sativa subsp.japonica)品种为研究对象,探究碳离子束辐照处理后不同水稻品种的辐照敏感性差异以及差异较大品种间苗期生理指标的区别。实验结果表明碳离子束(0、80、160Gy,80 Me V·u^(-1))对不同水稻品种的...以12个东北粳稻(Oryza sativa subsp.japonica)品种为研究对象,探究碳离子束辐照处理后不同水稻品种的辐照敏感性差异以及差异较大品种间苗期生理指标的区别。实验结果表明碳离子束(0、80、160Gy,80 Me V·u^(-1))对不同水稻品种的萌发产生了不同程度的影响,其中辐照对‘通禾66’萌发影响最小,而对‘吉粳809’萌发影响最大。进一步研究表明,碳离子束辐照对‘吉粳809’根和芽的生长抑制作用更明显,此外,其H_(2)O_(2)、超氧阴离子(O_(2)^(-)·)和丙二醛(MDA)含量均明显高于‘通禾66’,而抗氧化酶活性及非酶抗氧化物含量低于‘通禾66’。综上所述,与‘通禾66’相比,‘吉粳809’对碳离子束辐照更敏感,而抗氧化系统在二者辐照敏感性差异中起着重要作用。展开更多
基金the National Natural Science Foundation of China(Nos.12005271 and 12005273)the National Key Research and Development Program of China(No.E022223Y)+1 种基金the Western Talent Program of Chinese Academy of Sciences(No.29Y86205)the Key Deployment Project of Chinese Academy of Sciences(No.KFZD-SW-222).
文摘The use of carbon-ion radiotherapy(CIRT)is gradually increasing.Owing to the generation of high-energy secondary neutrons during CIRT,its use presents new challenges in radiation protection.Thus,secondary neutron dose distributions must be explored and evaluated under clinical scenarios based on different treatment configurations.However,neutron dose and energy spectrum measurements are often difficult.This can be primarily attributed to the inherent limitations of most neutron detectors,such as their unsuitability for spectral measurements and inaccurate responses to neutrons with energies above 20 MeV.Numerical calculation methods based on probabilistic statistical theory are fast and convenient for neutron dose evaluation.In this study,external secondary neutron doses at the heavy ion medical machine in Wuwei,which is equipped with a passive beam delivery system,were calculated using the Monte Carlo method.The dependence of neutron doses on various treatment parameters(incident carbon-ion beam energy,spatial location,field size,and spread-out Bragg peak(SOBP)width)was investigated.Furthermore,the feasibility of applying an analytical model to predict the ambient dose equivalent was verified.For the combination involving an energy of 400 MeV=u and SOBP width of 6 cm,the ambient dose equivalent per therapeutic dose(H=D)at the isocenter was 79.87 mSv=Gy:The H=D value decreased rapidly with increasing spatial distance and slightly with increasing aperture size and SOBP width.The H=D values derived from the Monte Carlo simulations were in good agreement with the results reported in the literature.The analytical model could be used to quickly predict the H=D value along the incidence direction of the beam with an error of less than 20%.Thus,our study contributes to the understanding of the relationship between neutron radiation and treatment configuration parameters,which establishes a basis for predicting non-therapeutic radiation doses in CIRT.
文摘The Er3＋/yb3＋ co-doped phosphate （EYDP） glass waveguides operated at 1539 nm have been manufactured by using the implantation technique of carbon ions under the condition of 6.0 MeV energy and 5.0 × 10^13 ions/cm2 fluence in this work. The ion implantation process was computed by means of the stopping and range of ions in matter. The dark-mode spectrum at 1539 nm of the waveguide was recorded by the method of the prism coupling measurement. The microscopic image of the fabricated structure was photographed by an optical microscope. It is the first step for the application of the waveguides on the base of EYDP glasses in optical- integrated photonic devices at near-infrared band.
基金Supported by Key R&D Plan of Science and Technology Program of Gansu Province,China,No.19YF3FH001.
文摘BACKGROUND Although the bystander effect and abscopal effect are familiar in medicine,they are relatively rare in clinical practice.Herein,we report the case of a patient who demonstrated an obvious bystander effect and abscopal effect response following carbon-ion irradiation for recurrent thymic carcinoma.CASE SUMMARY A 44-year-old female presented with shortness of breath.Eleven years prior,she was diagnosed with athymic tumor located in the anterosuperior mediastinum.She underwent extensive tumor resection,and the postoperative pathologic diagnosis was thymic carcinoma.She was administered 50 Gy/25 Fx of postoperative radiation.In 2019,she was diagnosed with a recurrence of thymic carcinoma,with multiple recurrent nodules and masses in the left thoracic chest and peritoneal cavity,the largest of which was in the diaphragm pleura proximal to the pericardium,with a size of 6.7 cm×5.3 cm×4.8 cm.She received carbonion radiotherapy.After carbon-ion radiotherapy treatment,the treated masses and the untreated masses were observed to have noticeably shrunk on the day of carbon-ion radiotherapy completion and on follow-up imaging.We followed the CARE Guidelines for consensus-based clinical case reporting guideline development and completed the CARE Checklist of information to report this case.CONCLUSION This report is the first of obvious abscopal and bystander effects following carbonion irradiation in a human patient,and further research is needed to better elucidate the mechanisms of bystander and abscopal effects.
文摘Hepatic epithelioid hemangioendothelioma(HEH)is a rare neoplasm of vascular origin with variable malignant potential.Because most patients with this condition have multiple bilobar lesions,liver transplantation is the standard treatment,and hepatectomy is much less frequently indicated.We describe a case of a 35-yearold woman with unresectable multiple bilobar HEH successfully treated by combination treatment with hepatectomy and carbon-ion radiotherapy.This case is very meaningful since it demonstrated the effectiveness of carbon-ion radiotherapy for HEH and the possibility of expanding the curative treatment options for multiple bilobar hepatic tumors.
文摘In order to see whether carbon ion (C-ion) beams have a biological advantage over X-rays, studies were designed to examine the effects of C-ion beams on radiosensitivity in X-ray resistant cells. Clinically relevant X-ray resistant SAS-R cells derived from human tongue cancer SAS cells were used. The cells were exposed to X-rays or Spread-Out Bragg peak (SOBP) beam C-ions. Cell survival was measured using a modified high-density survival assay. Cell survival signaling and cell death signaling were analyzed using flow cytometry. The cells were labeled with putative cancer stem cell markers such as CD44 and CD326. SAS-R cells were 1.6 times more radioresistant than SAS cells after exposure to X-rays. Cell survival was similar in each cell line after exposure to C-ion beams. SAS-R cells displayed enhanced cell survival signaling when compared to SAS cells under normal conditions. On the other hand, the phosphorylation of AKT-related proteins decreased and polycaspase activities were enhanced when cells were irradiated with C-ion beams in both cell lines. More CD44 and CD326 positive cells were seen in SAS-R cells than in SAS cells. Moreover, the marker positive cell numbers significantly decreased after exposure to C-ion beams when compared to X-rays at iso-survival doses in SAS-R cells. C-ion beams efficiently induced cell killing in X-ray resistant cells which displayed activated cell survival signaling and contained more numerous cancer stem-like cells.
基金supported by National Key Research and Development Program of China(No.2022YFC2401503)National Natural Science Foundation of China(Nos.11875299,61631001,U1532264,and 12005271).
文摘Intensity-modulated particle therapy(IMPT)with carbon ions is comparatively susceptible to various uncertainties caused by breathing motion,including range,setup,and target positioning uncertainties.To determine relative biological effectiveness-weighted dose(RWD)distributions that are resilient to these uncertainties,the reference phase-based four-dimensional(4D)robust optimization(RP-4DRO)and each phase-based 4D robust optimization(EP-4DRO)method in carbon-ion IMPT treatment planning were evaluated and compared.Based on RWD distributions,4DRO methods were compared with 4D conventional optimization using planning target volume(PTV)margins(PTV-based optimization)to assess the effectiveness of the robust optimization methods.Carbon-ion IMPT treatment planning was conducted in a cohort of five lung cancer patients.The results indicated that the EP-4DRO method provided better robustness(P=0.080)and improved plan quality(P=0.225)for the clinical target volume(CTV)in the individual respiratory phase when compared with the PTV-based optimization.Compared with the PTV-based optimization,the RP-4DRO method ensured the robustness(P=0.022)of the dose distributions in the reference breathing phase,albeit with a slight sacrifice of the target coverage(P=0.450).Both 4DRO methods successfully maintained the doses delivered to the organs at risk(OARs)below tolerable levels,which were lower than the doses in the PTV-based optimization(P<0.05).Furthermore,the RP-4DRO method exhibited significantly superior performance when compared with the EP-4DRO method in enhancing overall OAR sparing in either the individual respiratory phase or reference respiratory phase(P<0.05).In general,both 4DRO methods outperformed the PTV-based optimization in terms of OAR sparing and robustness.
文摘以12个东北粳稻(Oryza sativa subsp.japonica)品种为研究对象,探究碳离子束辐照处理后不同水稻品种的辐照敏感性差异以及差异较大品种间苗期生理指标的区别。实验结果表明碳离子束(0、80、160Gy,80 Me V·u^(-1))对不同水稻品种的萌发产生了不同程度的影响,其中辐照对‘通禾66’萌发影响最小,而对‘吉粳809’萌发影响最大。进一步研究表明,碳离子束辐照对‘吉粳809’根和芽的生长抑制作用更明显,此外,其H_(2)O_(2)、超氧阴离子(O_(2)^(-)·)和丙二醛(MDA)含量均明显高于‘通禾66’,而抗氧化酶活性及非酶抗氧化物含量低于‘通禾66’。综上所述,与‘通禾66’相比,‘吉粳809’对碳离子束辐照更敏感,而抗氧化系统在二者辐照敏感性差异中起着重要作用。
