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Objective:To explore the clinical value of 18F-fluoromisonidazole (FMISO) PET/CT hypoxia imaging in early response to heavy ion radiotherapy in patients with non-small cell lung cancer(NSCLC). Methods:From April 2018 to January 2021, the 18F-FMISO PET/CT images of 23 NSCLC patients (19 males, 4 females; age (64.9±10.3) years) who received heavy ion radiotherapy in Shanghai Proton and Heavy Ion Center were retrospectively analyzed. The evaluation parameters included tumor volume (TV), tumor to background ratio (TBR) before and after radiotherapy. Patients were divided into hypoxia group and non-hypoxia group with the baseline TBR value≥1.4 as hypoxia threshold. Wilcoxon signed rank test was used to compare the differences of TV and TBR before and after radiotherapy in 2 groups. Results:Of 23 NSCLC patients, 17 were hypoxia and 6 were non-hypoxia. Compared with the baseline, TV after the radiotherapy (59.44(22.86, 99.43) and 33.78(8.68, 54.44) cm 3; z=-3.05, P=0.002) and TBR after the radiotherapy (2.25(2.09, 2.82) and 1.42(1.24, 1.67); z=-3.39, P=0.001) of the hypoxia group were significantly lower, while TV (16.19(6.74, 36.52) and 8.59(4.38, 25.47) cm 3; z=-1.57, P=0.120) and TBR (1.19(1.05, 1.27) and 1.10 (0.97, 1.14); z=-1.89, P=0.060) of the non-hypoxia group decreased with no significant differences. Conclusions:Hypoxic NSCLC tumors are sensitive to heavy ion radiation. Compared with non-hypoxic tumors, hypoxic tumors respond more quickly, and a significant reduction in TV can be observed early after radiotherapy. Heavy ion radiation can significantly improve tumor hypoxia.
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Objective:To study and analyze the uncertainty of active breathing coordinator (ABC) technology for liver and lung cancer therapy using proton and heavy ion.Methods:Before each treatment, each patient received a verification radiograph through the supporting imaging frame in treatment room. 200 verification radiographs were taken for 20 lung cancer patients and 200 for 20 liver cancer patients. Ipiodol markers, which were fixed relative to the location of the tumor, were injected into the liver cancer patients. The position changes of ipiodol markers could reflect the position changes of liver tumors. Verification radiographs were registered with the vertebral body as the main target, and the change value of tumor location was recorded.Results:For liver cancer cases, the values of position change in the left and right, head and foot, and dorsal abdomendirection were (-0.05± 0.28) cm, (0.15±0.33) cm, (-0.12±0.27) cm, and (-0.03±0.13) cm, (-0.05±0.14) cm and (0.02±0.16) cmfor lung cancer cases, respectively ( P=0.280, <0.001, <0.001). For liver cancer cases, the dispersionin the left and right, head and foot, and dorsal abdomendirectionwas (0.20±0.09) cm, (0.25±0.06) cm, (0.19±0.09) cm, and (0.09±0.03) cm, (0.10±0.03) cm and (0.13±0.03) cm for lung cancer cases, respectively ( P<0.001, <0.001, 0.008). The proportion of tumor location changes of≤5 mm in three directions in liver and lung cancer patientswas (92%, 83%, 93%) vs. (99%, 99%, 100%)( P=0.030, 0.002, 0.007). Conclusion:The application of ABC technology in the proton heavy ion therapy of lung and liver cancer has good reproducibility, and the stability of ABC technology in the treatment of lung cancer is better than that of liver cancer.
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Objective:To understand the effects of proton and heavy ion radiotherapy on nutritional status in patients with malignant tumors and to analyze the influencing factors of adverse events.Methods:Patients with malignant tumors who received proton and heavy ion therapy between October 2016 and September 2021were retrospectively included. The demographic characteristics, clinical diagnosis, radiotherapy regimen, nutritional indicators and adverse events were collected. Paired t test was used to analyze the changes in nutritional status before and after treatment and logistic regression was used to analyze the influencing factors of adverse events. Results:A total of 2,390 patients were enrolled and were stratified into 4 groups according to different radiotherapy regimen, namely proton, heavy ion, proton + heavy ion and photon + heavy ion radiotherapies. The prevalence of nutritional risk were 17.5% and 27.8% at admission and discharge, respectively. The prevalence of nutritional risk at discharge were 73.9% ( χ2 = 237.149, P < 0.01) in patients who received photon + heavy ion radiotherapy and 30.8% ( χ2 = 36.925, P < 0.01) in those who received proton + heavy ion radiotherapy. The prevalence of critical weight loss at discharge was 14.1%, with the absolute weight loss of 4.84 kg ( t = 11.716, P < 0.01) and 1.52 kg ( t = 29.530, P < 0.01) in photon + heavy ion radiotherapy and proton + heavy ion radiotherapy groups, respectively. All groups showed significant changes in serum albumin (ALB) and total lymphocyte count (TLC). Specifically, photon + heavy ion and proton + heavy ion therapy had a greater effect on serum ALB and TLC, with a decrease of 2.88 g/L and 2.18 g/L for ALB as well as a decrease of (1.06×10 9) /L and (0.80×10 9) /L for TLC ( P < 0.01). Multivariate logistic regression analysis showed that nutritional risk at admission and concurrent chemotherapy were independent factors for adverse events of proton and heavy ion radiotherapy ( OR = 1.404, 95% CI: 1.039 to 1.898; OR = 2.370, 95% CI: 1.781 to 3.154). Compared with heavy ion radiotherapy, the other 3 groups had more adverse events (proton, OR = 3.982, 95% CI: 2.533 to 6.259; proton + heavy ion, OR = 4.995, 95% CI: 3.688 to 6.766; photon + heavy ion, OR = 7.716, 95% CI: 5.079 to 11.720). Conclusions:Patients receiving proton and heavy ion therapy showed poorer nutritional status. Photon + heavy ion therapy had the greatest impact on nutritional status. Nutritional risk at admission and concurrent chemotherapy were independent factors for adverse events in patients receiving proton and heavy ion therapy.
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In recent years, heavy ion beams have received great attention in the field of malignant tumor radiotherapy due to their radiation physics and biological characteristics. The high rate of local tumor control is one of its advantages, but the control rate of metastatic lesions is still crucial in the treatment of most malignant tumors. Clinical studies on the combined conventional radiotherapy and immunotherapy suggest that the combination of the two can not only control the primary lesions, but may also reduce or completely eliminate distant metastatic lesions. High linear energy transfer radiation, especially heavy ion beams, may have stronger potential in combined immunotherapy. Therefore, this article focuses on the basic research progress of heavy ion beams regulating anti-tumor immune effects and their combined application with immunotherapy.
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Objective:To investigate the expression changes at the transcriptional level in normal lung tissues of mice after exposure to heavy ion radiation for different durations at different doses, aiming to provide evidence for exploring sensitive genes of heavy ion radiation, heavy ion radiation effect and the damage mechanism.Methods:Experiments on the temporal kinetics: the whole thorax of mice was irradiated with 14.5Gy carbon-ions and the total RNA of lung tissue was extracted at 3days, 7days, 3 weeks and 24 weeks. In dose-dependent experiment, the total RNA of lung tissue was extracted at 1 week after irradiated with a growing thoracic dose of 0, 7.5, 10.5, 12.5, 14.5, 17.5 and 20Gy. Protein-to-protein interaction (PPI) analysis and gene-ontology biological process enrichment analysis were performed on significant differentially expressed genes (DEGs).Results:A clearly differential expression patterns were observed at 3-day (acute stage), 1-week (subacute stage), 3-week (inflammatory stage) and 24-week (fibrosis stage) following 14.5Gy carbon-ions irradiation. Among those, the 3-day time point was found to be the mostly different from the other time points, whereas the 7-day time point had the highest uniformity with the other time points. Cellular apoptosis was the main type of cell death in normal lung tissues following carbon-ions exposure. The interactive genes of Phlda3, GDF15, Mgmt and Bax were identified as the radiosensitive genes, and Phlda3 was the center ( R=0.76, P<0.001). Conclusion:The findings in this study provide transcriptional insights into the biological mechanism underlying normal lung tissue toxicity induced by carbon-ions.
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OBJECTIVE: Programmed cell death-ligand 1 (PD-L1) is expressed in tumor cells and has been shown to predict clinical outcomes of several types of malignancies. The aim of this study was to investigate the effects of carbon-ion (C-ion) beam irradiation on PD-L1 expression in human uterine cervical adeno/adenosquamous carcinoma (UCAA) cells and clinical samples and to identify the prognostic factors for outcomes after C-ion radiotherapy (CIRT).METHODS: The effects of C-ion irradiation on PD-L1 expression in human UCAA and cervical squamous cell carcinoma cells were examined by flow cytometry. We examined PD-L1 expression in UCAA biopsy specimens from 33 patients before CIRT started (pre-CIRT) and after 12 Gy (relative biological effectiveness [RBE]) irradiation (post-12Gy-C) in 4 fractions of CIRT to investigate the correlation between PD-L1 status and clinical outcomes.RESULTS: The PD-L1 expression was upregulated by C-ion beam in a dose-dependent manner in HeLa and SiHa cells through phosphorylated Chk1. The overall frequencies of pre-CIRT and post-12Gy-C PD-L1 positivity were 45% (15/33) and 67% (22/33), respectively. The post-12Gy-C PD-L1 expression was significantly elevated compared to the pre-CIRT PD-L1 expression. There was no significant relationship between the pre-CIRT PD-L1 status and clinical outcomes, such as local control (LC), progression-free survival (PFS), and overall survival (OS). However, the post-12Gy-C PD-L1 expression had better correlation with PFS, but not with LC and OS.CONCLUSION: CIRT can induce PD-L1 expression in UCAA and we propose that PD-L1 expression after starting CIRT may become as a predictive prognostic marker in CIRT for UCAA.
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Humans , B7-H1 Antigen , Biopsy , Carcinoma, Squamous Cell , Disease-Free Survival , Flow Cytometry , Heavy Ion Radiotherapy , Radiotherapy , Treatment Outcome , Uterine Cervical NeoplasmsABSTRACT
Compared with proton and photon, heavy ion radiotherapy has unique physical and biological advantages, which enables it to kill tumor tissues to the greatest degree and protect surrounding normal tissues as much as possible. Carbon ion is recognized as the most suitable heavy ion for radiotherapy at present. Carbon ion radiotherapy in chordoma, head and neck cancer, non-small cell lung cancer, prostate cancer, cervical cancer and other malignant tumor treatment advantages have been preliminarily reflected. Therefore, understanding the characteristics of carbon ion radiotherapy and its application in tumor therapy will help clinicians make better clinical decisions in the future.
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Carbon-ion beam (CIB) is a high-linear energy transfer (LET) radiation. CIB is featured with more superior physical dose distribution (i.e., Bragg Peak) as compared to photon beam. In addition, it induces more double-bond break thus has higher relative biological effectiveness (RBE) as compared to photon beam. The combined use of chemotherapy and conventional photon radiotherapy has been widely used in the treatment of tumors. Chemotherapy is used concurrently with photonradiotherapy due to its radiosensitization. However, the radiosensitization effect of chemotherapy used with carbon-ion radiotherapy is controversial. In this article, we reviewed the previous studies of biological effects of the combination of carbon ion radiotherapy and chemotherapy in basic biological studies (including cytological and animal experiments) and clinical outcomes, and elaborated the biological effects.
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Cancer therapy with accelerated proton or heavy ion beam is the most advanced radiotherapy technology, which is recognized by the international community at present. It is of great practical significance to study the medical proton and heavy ion accelerators and the radiotherapy technology, in order to promote the development of the advanced medical radiotherapy equipments and improve the quality of life of cancer patients in China. After a brief overview of cancer therapy with proton and heavy ion beam, this paper summarized and analyzed the application status of medical proton accelerators and medical heavy ion accelerators at home and abroad, and finally put forward the future development trends of medical proton and heavy ion accelerators and the radiotherapy technology, it can provide a reference for the progress and development strategies of the advanced radiotherapy equipments in China.
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Humans , China , Heavy Ions , Neoplasms , Therapeutics , Particle Accelerators , Proton Therapy , Protons , Quality of LifeABSTRACT
Compared with proton and photon,heavy ion radiotherapy has unique physical and biologi-cal advantages,which enables it to kill tumor tissues to the greatest degree and protect surrounding normal tissues as much as possible. Carbon ion is recognized as the most suitable heavy ion for radiotherapy at present. Carbon ion radiotherapy in chordoma,head and neck cancer,non-small cell lung cancer,prostate cancer,cer-vical cancer and other malignant tumor treatment advantages have been preliminarily reflected. Therefore, understanding the characteristics of carbon ion radiotherapy and its application in tumor therapy will help clini-cians make better clinical decisions in the future.
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Summary The study of heavy ion nuclear reactionis an important tool to observe and disentangle different and competing mechanisms, which may arise in the different energy regimes. In particular, at relatively low bombarding energy, it is quite interesting the comparison between pre-equilibrium and thermal emission of light charged particles from hot nuclear systems [1-6]. Indeed, the nuclear structure of the interacting partners can be strongly correlated to the dynamics, especially at energies close to the Coulomb barrier, and this effect emerges when some nucleons or clusters of nucleons are either emitted or captured. In particular, a major attention has been devoted, in the last years, to the possible observation of cluster structure effects in the competing nuclear reaction mechanisms, especially when fast processes are involved. At this purpose, the four reactions 16O+30Si at 111 MeV, 16O+30Si at 128 MeV, 18O+28Si at 126 MeV, 19F+27Al at 133 MeV have been measured to study the onset of pre-equilibrium in an energy range where, for central collisions, complete fusion is expected to be the predominant mode. Experimental data were collected using the GARFIELD + RCo array [7], fully equipped with digital electronics at the LegnaroNational Laboratories. The comparison between experimental data and different model predictions have been performed: in particular, both dynamical models based either on Stochastic Mean Field (TWINGO) or Anti-symmetrized Molecular Dynamics and fully statistical models (GEMINI++) have been considered. Simulated events are filtered through a software replica of the apparatus, to take into account all possible distortions of the experimental distributions due to the finite size of the apparatus.
Resumen El estudio de la reacción nuclear iónica pesada es una herramienta importante para observar y esclarecer los diferentes mecanismos que compiten entre sí, que pueden surgir en los diferentes regímenes energéticos. En particular, a una energía de bombardeo relativamente baja, es bastante interesante la comparación entre el preequilibrio y la emisión térmica de partículas ligeras cargadas por sistemas nucleares calientes [1-6]. De hecho, la estructura nuclear del grupo que interactúa puede estar fuertemente correlacionada con la dinámica, especialmente en energías cercanas a la barrera de Coulomb, y este efecto surge cuando se emiten o capturan algunos nucleones o grupos de nucleones. En particular, se ha dedicado una gran atención, en los últimos años, a la posible observación de los efectos de la estructura del agrupamiento en los mecanismos de reacción nuclear competitivos, especialmente cuando se trata de procesos rápidos. Para este propósito, las cuatro reacciones 16O + 30Si a 111 MeV, 16O + 30Si a 128 MeV, 18O + 28Si a 126 MeV, 19F + 27Al a 133 MeV se han medido para estudiar el inicio del preequilibrio en un rango de energía en el cual, para colisiones centrales, se espera que la fusión completa sea el modo predominante. Los datos experimentales se recogieron utilizando la matriz GARFIELD + RCo [7], totalmente equipada con electrónica digital en los Laboratorios Nacionales Legnaro. La comparación entre los datos experimentales y las diferentes predicciones de modelos se han llevado a cabo: en particular, se han considerado los modelos dinámicos basados en el Campo Medio Estocástico (TWINGO) o Dinámica Molecular Antisimétrica y modelos completamente estadísticos (GEMINI ++). Los eventos simulados se filtran a través de una réplica de software del aparato, para tener en cuenta todas las posibles distorsiones de las distribuciones experimentales debido al tamaño finito del aparato.
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Objective To compare the application values and setup errors between vacuum bag plus body mask and customized alpha cradle duringproton and carbon therapy using Siemens 6D robotic couch in prostate cancer patients.Methods Nineteen patients received vacuum bag plus body mask setup were allocated into the vacuum bag group andl9 patients with alpha cradle were assigned into the alpha cradle group.Orthogonal X-ray portals were performed to verify the treatment position before beam delivery in every fraction.The couch correction between the portal and reference DRR through manual image registration was recorded as setup errors in 6 directions including the lateral,supine-inferior,anterior-posterior,yaws,roll and pitch,respectively.Two-tail t-test was used to analyze the setup error data from each direction between two groups.Results In total,452 and 436 sets of data errors were collected from the vacuum bag and alpha cradle groups.The average setup errors and standard deviation in the vacuum bag and alpha cradle groups in the lateral,supine-inferior,anterior-posterior,yaws,roll and pitch directions were (0.63±0.48) cm vs.(0.33±0.24) cm (P=0.000),(0.40±0.3) cm vs.(0.31±0.25) cm (P=0.000),(0.69±0.61) cm vs.(0.82±0.69) cm (P=0.006),0.65°±0.47°vs 0.32°±0.25°(P=0.000),1.05°±0.95°vs 1.16°±0.94° (P=0.100) and 0.67°±0.56°vs 0.40°±0.36° (P=0.000),respectively.The maximum setup errors were detected in the pitch direction for both groups.Conclusions During the proton and carbon therapy using Siemens 6D robotic couch,two setup methods using vacuum bag plus body mask and customized alpha cradle should be selected according to the individual conditions of patients.A customized foot fixer should be utilized to reduce the uncertainty in the femoral head region.
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Objective To assess the occupational exposure doses received by the physicians in clinical practice at Shanghai Proton and Heavy Ion Center ( SPHIC ) . Methods A total of 40 patients treated from September to November in 2016, including 20 proton cases and 20 carbon cases at SPHIC, were selected using simple random sampling method. Particle type, total particle number and prescribed doses were recorded for all the cases. The dose rates in the control room were measured by using a photon and neutron personal radiation detector during patient treatment. The dose rates around the surface of the patient's tumor 1 min after completion of beam delivery and the dose rates about 30 cm to the tumor surface (where a physician stands) were also measured during unfixing and assisting the patients. Finally, the dose rates surrounding the fixtures, couch, robotic arm and window of BAMS were measured. The factors affecting the occupational exposure of physician were analyzed and the annual dose equivalent was assessed for physicians in SPHIC. Results Proton and heavy ion released nearly all energy in the tumor for Bragg peak advantage, so there was no induced radioactivity in the treatment room. However, the tumor became the main induced radioactivity source to the occupational exposure dose to physicians in clinical practices. The dose rate around the surface of the patient's tumor 1 min after completion of beam delivery was (20. 68 ± 21. 91) μSv/h, which was the highest in the working places of physicians, thus regarded as the main source. A significant positive correlation (r=0. 828, P<0. 05) was shown between dose rates and total number of particles delivered for the treatment. The dose rate measured in the control room was (0. 08 ± 0. 01 )μSv/h, and the dose rate measured surrounding the fixtures, couch, robotic arm and BAMS window was ( 0. 09 ± 0. 01 )μSv/h. No neutron was detected. The dose rate about 30 cm to the tumor surface ( where physicians stand) was ( 2. 03 ± 2. 84 ) μSv/h during unfixing and assisting the patients. The average annual dose to physicians was about 0. 508 mSv. Conclusions The average annual dose to physicians was at a low level in SPHIC
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Malignant Melanoma derived from melanocytes,characterized by early metastasis and high mortality,is the most aggressive malignancy among the skin cancers,and also found in mucous membranes,eyes and other parts of the choroid.It is traditionally considered to be radio-resistant to conventional radiotherapy.However,the emergence of heavy ion radiotherapy has drastically improved the treatment effect of the melanoma.Because of the inverted depth-dose distribution,the energy of heavy ions is precisely deposited in the tumor site,so as to protect the surrounding normal tissues.Heavy ions provide higher biological effectiveness and a lower oxygen effect compared with photons.So,it is an advanced radiotherapy method in the 21st century.In this review,we summarized the biological effects researches and clinical applications of heavy ions in the treatment of malignant melanoma,hopefully providing a reliable reference for future standardized heavy ion treatment of malignant melanoma.
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Objective: To design an online pure water analysis system based on the proton and heavy ion accelerator (IONTRIS system) in Shanghai proton and heavy ion center (SPHIC), and to evaluate its application effect by operating data statistics. Methods: The system used the control system of Siemens S7-300 PLC to collect online data from sensors of pure water system. Analyzing the operation rules and setting the limiting value of alarm, and using WINCC software to develop monitoring and analysis system of central computer so as to real-time operate online data. The application effect of the system was evaluated by comparing the cost of one month consumables between before and after the system was applied. Results: After the system was applied, the real-time monitoring of pure water system was realized, and the efficiency of the consumables was enhanced. Conclusion: The application of the pure water analysis system has a good effect on the operation efficiency of the pure water system.
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Objective To explore the influence of Guiqiyiyuan Ointment on the expressions of caspase-3 and caspase-9 in the lung and kidney of the rats damaged by heavy ion (12C6+) radiation-induced bystander effect.Methods The Wistar male rats were equally and randomly divided into seven groups,normal control group (NCG),radiation alone group (RAG) and Chinese medicine group (CMG),with the latter two groups being redivided into 6,12 and 24h groups according to the executing time.The Chinese medicine groups were given Guiqiyiyuan Ointment by gavage for two weeks in advance.The normal control group and the radiation alone groups were given the equal normal saline.Afterwards,the right lung of the rats in the radiation alone groups and Chinese medicine groups were radiated by 2Gy 12C6+ ion once.The rats in normal control group were not radiated.All groups of rats were executed 6,12,and 24h after radiation.The protein and mRNA expressions of caspase-3 and caspase-9 in the right lung,left lung and left kidney were examined with immunohistochemistry and Q-PCR.Results Compared with the normal control group,the mRNA expressions of caspase-3 and caspase-9 in the right lung,left lung and left kidney in the radiation alone groups obviously increased 6 and 24h after radiation.While the protein expressions of caspase-3 and caspase-9 in the radiation alone group obviously increased only 24h after radiation (P＜0.01).Compared with the radiation alone groups,the expressions of protein and mRNA ofcaspase-3 and caspase-9 were obviously down-regulated in the Chinese medicine groups (P＜0.01).Conclusion By controlling the up-regulation of the expression ofcaspase-3 and caspase-9,Guiqiyiyuan Ointment can prevent the lung and kidney cell apoptosis and alleviate the damage caused by heavy ion radiation-induced bystander effect in vivo.
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ABSTRACT Screening promising L. thermophiles with high productivity, high efficiency and strong adaptability are very important in lactic acid industry. For this purpose, 80MeV/u carbon ions were applied to irradiate L. thermophiles. After high-throughput screening, a mutant, named SRZ50, was obtained. Different carbon sources or nitrogen sources were provided to investigate carbon or nitrogen source utilization between mutant SRZ50 and wild type, and different fermentation periods were also chose to study fermentation characteristic between mutant SRZ50 and wild type. The results showed that mutant SRZ50 exhibited the enhanced L-(+)-lactic acid production from wild type. When glucose or fructose was the sole carbon source, the L(+)-lactic acid production by mutant SRZ50 was both the highest, respectively, 23.16 ± 0.72 g/L or 23.24 ± 0.66 g/L, which had a significant increase from that of wild type (P<0.01), following obvious increase in biomass (P<0.05). When yeast powder was the sole nitrogen source, it can promote mutant SRZ50 to accumulate the highest L-(+)-lactic acid accumulation, which also had a significant increase from that of wild type (P<0.01). Under different fermentation periods, it was obtained that mutant SRZ50 all exhibited significant increase in L-(+)-lactic acid accumulation from wild type. In conclusion, a mutant strain with improved production profiles for L-(+)-lactic acid, was obtained, indicating that heavy ions can be an efficient tool to improve metabolic product accumulations in microbes.
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Objective:To research the prevention and emergency optimization of shutdown fault of cooling water system of proton and heavy ion accelerator, and elucidate their application effect through analyzed the fault of cooling water system of accelerator (IONTRIS) in SPHIC.Methods: Through analyzed the reasons of shutdown faults, the predictive diagnosis and reconstruction scheme of shutdown fault were implemented. The voltage compensator was installed for preventing the voltage fluctuation of external power grid. And the detection method of mechanical vibration was used to prevent fault of water pump. The emergency constant pressure facility and rapid switching system of fault were designed and installed to prevent fault of constant pressure facility. At the same time, the emergency system of preventing leakage was designed and installed to reduce the risk of water leakage.Results: After the optimal emergency scheme was implemented, the ability of fault emergency of cooling water system of proton and heavy ion accelerator were enhanced and improved.Conclusion: The design and operation of large medical facilities need to fully consider the requirements for security and redundancy and scheme for faults diagnosis and emergency.
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Objective To discuss the protective effects ofGuiqi YiyuanOintment on damages caused by heavy ion radiation induced bystander effects; To explore the possible mechanism.Methods Totally 42 Wistar male rats were randomly divided into blank control group, pure radiation group andGuiqi Yiyuan Ointment group. TheGuiqi Yiyuan Ointment group was givenGuiqi Yiyuan Ointment by gavage for two weeks in advance. Later the right lungs of the rats in the pure radiation group andGuiqi Yiyuan Ointment group were radiated once by 2 Gy12C6+, while the blank control group received no radiation. 6, 12, 24 h after radiation all groups of rats were executed. Peripheral hemogram and the levels of IL-6, TGF-β1 and IL-1β in serum of the rats were examined. The changes of lung tissue pathology morphology in the rats were observed by HE staining.Results Compared with the blank control group, the contents of IL-6, TGF-β1 and IL-1β in serum of the pure radiation group increased obviously at 12 h after radiation (P<0.01), and the amount of leukocyte, erythrocyte, blood platelet and hemoglobin distinctly declined at 12 h after radiation (P<0.01); HE staining showed that the alveolar wall was thickened at 24 h after radiation, and there were exudate and inflammatory cell infiltration in the alveolar cavity. Compare with the pure radiation group at 12 h after radiation, the levels of IL-6, TGF-β1 and IL-1β inGuiqi Yiyuan Ointment group decreased significantly at 12 h after radiation (P<0.01). Indexes of blood routine significantly increased (P<0.01), and the pathological changes of lung tissue in rats improved (P<0.01). ConclusionGuiqi Yiyuan Ointment can protect damages caused by heavy ion radiation induced bystander effects.
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Objective To study the temperature control method of the cooling water system for Siemens medical proton and heavy-ion synchrotron.Methods The return water temperature was used as the input variable of the control program,temperature prediction method was applied to controlling valve opening,and the capacity of water tank at backwater-side was increased to enhance temperature buffer capability.Results The optimized system adapted itself to multi loading conditions of the synchrotron,which achieved 2 ℃ peak elimination in case of return water at 32 ℃ or less to limit the input water temperature within (27±1) ℃.The failure rate of temperature deviation was decreased from 64％ to 8％.Conclusion The optimized cooling water system with three-layer structure fulfills the requirements of Siemens proton heavy-ion synchrotron operation.