重离子束在微生物诱变育种及生物能源开发中的应用

作为一种新型的辐射诱变源, 重离子束在辐射诱变育种中的优越性已经显现。 在此基础上综述了重离子束用于微生物诱变育种的基本原理、 独特优点、 所取得的成果及研究进展, 并对其在新型生物能源开发中的潜力进行了展望。As a new radiation source, heavy ion beams have demonstrated the outstanding advantage in mutation breeding. Based on this background, the basic principal and unique peculiarity of heavy ion beams, the achievement and the progress in the research of microbial mutation breeding are reviewed in the paper. The potential application of heavy ion beams to new biological energy is also prospected.     

重离子束治疗肿瘤临床研究

文章综述了重离子束在物理学、生物学、临床治疗等方面的优势,以及在放射生物学方面的基础实验研究内容。分析总结了国内外重离子束辐照治疗肿瘤的临床研究结果。其中,日本已接受治疗了约6 000 名不同类型的肿瘤患者,并取得较高的局部控制率和生存率;德国在头颈部肿瘤临床治疗方面取得了巨大的成功;在兰州重离子研究装置(HIRFL) 肿瘤治疗终端上,中国科学院近代物理研究所联合甘肃省肿瘤医院及兰州军区总医院对肿瘤患者的重离子治疗已进入临床试验阶段。甘肃省肿瘤医院治疗结果显示:43 例患者通过影像学检查评价疗效,客观有效率(CR+PR)为71.4%,主要急性放射损伤为1-2 级皮肤反应(红斑形成和脱皮),发生率为61.9%,治疗1 个月后随访结果显示重离子束(12C6+)对深部肿瘤具有较好的局部控制作用,且无严重不良反应发生。This article reviews the advantages of heavy ion in physical, biological and clinical aspects, discusses the radio-biological basis of experiment research, and summarizes clinical results of heavy ion beam treatment on tumor at home and abroad. Japan has accepted and treated about 6000 cancer patients of different types with high local control rates and survival ones. Germany has achieved great success in head and neck tumor clinical treatment. Institute of Modern Physics, Chinese Academy of Sciences (IMP-CAS), Tumor Hospital of Gansu Province and Lanzhou General Hospital of PLA have begun clinical trial on heavy ion treatment of deep-seated tumors after the shallow-seated tumor therapy has been done at HIRFL (Heavy Ion Research Facility in Lanzhou). The treatment results of Tumor Hospital of Gansu Province show that the objective response rate (CR+PR) is 71.4% and the rate of 1-2 levels radiation injury to skin reactions (erythema and desquamation) is 61.9% when we evaluate the 43 patients by means of maging. The results of case follow-up after treatment in 1 month indicate that the deep-seated tumor therapy with heavy ion beam has high local control rates without severe adverse effect.     

重离子束适形放射治疗技术

重离子束适形放射治疗技术主要包括束流配送系统和治疗计划系统等 .前者是实现重离子束适形放射治疗的硬件设施 ,后者为适形治疗的软件支撑系统 ,两者缺一不可 .鉴于重离子束与物质相互作用在物理学及生物学效应上表现出的特殊性,重离子束治癌中特别引入了面向生物学效应的适形治疗和束流的正电子断层在线监控技术. The conformal radiotherapy techniques mainly include the two systems that are beam delivery and treatment planning. The formal is the hardware basis while the later is the software supplement for heavy ion conformal therapy, they are dependent on each other to realize the cancer conformal therapy with heavy ion beam. Because of the specificities of interaction between heavy ion and target on both physics and biological effects, the heavy ion cancer therapy especially involves...     

重离子束用于肿瘤放射治疗的基础理论

通过与低传能线密度辐射治疗对比分析建立了重离子束肿瘤放射治疗的基础理论,提出了一些提高重离子束放射治疗疗效和减少对正常组织损伤的技术措施,旨在为已开展的重离子治癌临床研究提供理论依据． The basic theory of tumor radiotherapy with heavy ion beam was introduced in contrast to low LET irradiation therapy. Some useful methods are also suggested to improve the curative effect of heavy ion therapy and to spare the normal tissue around the tumor.     

肿瘤细胞辐射敏感性相关蛋白研究进展

重点综述了Siah, HIF, NF-κB和DNA-PK蛋白与肿瘤细胞辐射敏感性关系的最新研究进展。 总结了中国科学院重离子束辐射生物医学重点实验室近几年来在BRCA1等肿瘤细胞辐射敏感性相关蛋白方面的研究工作。 简介了HLET C离子束治疗肿瘤的优点。 展望了此实验室借助兰州重离子研究装置(HIRFL)提供的C离子束研究肿瘤细胞辐射敏感性相关蛋白的目标和方向。 The research progress of tumor cells radiosensitivity associated protein Siah, HIF,NF-κB and DNA-PK are summarized and reviewed. The recent works of our laboratory on tumor cells radiosensitivity associated proteins such as BRCA1 are demonstrated. In the present review, we focused on discussions about the advantages of heavy ion therapy and its possible application in the research of radiosensitivity associated proteins. At the end of this review, we highlighted the future trend and potential targets in the study of tumor cells radiosensitivity associated proteins.     

Neutron dose measurement in carbon ion radiation therapy at HIRFL （IMP）

For radiation protection purposes, the neutron dose in carbon ion radiation therapy at the HIRFL （Heavy Ion Research Facility in Lanzhou） was investigated. The neutron dose from primary ^12C ions with a specific energy of 100 MeV/u delivered from SSC was roughly measured with a standard Anderson-Broun rem-meter using a polyethylene target at various distances. The result shows that a maximum neutron dose contribution of 19 mSv in a typically surface tumor treatment was obtained, which is less than 1% of the planed heavy ion dose and is in reasonable agreement with other reports. Also the T-ray dose was measured in this experiment using a thermo luminescent detector.     

C离子束放射治疗肿瘤的进展

重离子(C离子)用于肿瘤放射治疗具有物理学和生物学两方面的优势, 被誉为面向21世纪最佳放疗用射线。 综合论述了世界各国重离子束治癌的发展历史, 在日本国立放射医学综合研究所(NIRS)提供的临床试验数据基础上分析了C离子束治疗的适应症以及对正常组织的放射损伤。 此外, 通过分析潜在患者人数和治疗相关硬件与软件设备, 对C离子束治癌的运用前景做了初步评估。Heavy ions (carbon ions) were considered currently as the best radiation in radiotherapy for their two superiorities in the physical and biological properties. This paper firstly put the focus on the history of development of heavy ion radiotherapy in the world, then a comprehensive analysis of the indications and radiation damages of normal tissues in clinical trails of heavy ion therapy was made based on the published data by NIRS. Moreover, the prospect of using carbon ions in radiotherapy was estimated by analyzing the potential patients’ number, its related instruments and etc.     

Progresses of heavy-ion cancer therapy

The status of heavy-ion cancer therapy has been reviewed. The existing and constructing heavy-ion beam facilities for cancer therapy in the world are introduced. The first clinical trials of superficially placed tumor therapy at heavy ion research facility in Lanzhou (HIRFL) are presented.     

利用高能离子模拟研究反应堆结构材料中的辐照效应

简要介绍了载能粒子辐射损伤对反应堆结构材料性能的影响,阐述了载能粒子束特别是高能离子束开展模拟研究的优势,并举例说明了国内利用高能重离子模拟研究反应堆结构材料辐射效应取得的进展。实验结果和理论分析表明,载能离子特别是高能离子辐照非常适合用于模拟研究反应堆结构材料中由粒子辐射引起的材料微观结构和宏观性能变化,是模拟研究反应堆结构材料辐射效应的非常有效的手段。 Radiation damage in structural materials of fission/fusion reactors is mainly attributed to the evolution of intensive atom displacement damage induced by energetic particles （ n, α and/or fission fragments） and highrate helium doping by direct α particle bombardments and/or （n, α） reactions. It can cause severe degradation of reactor structural materials such as surface blistering, bulk void swelling, deformation, fatigue, embrittlement, stress erosion corrosion and so on that will significantly affect the operation safety of reactors. However, up to now, behavior of structural materials at the end of their service can hardly be fully tested in a real reactor. In the present paper, damage process in reactor structural materials is briefly introduced, then the advantages of energetic ion implantation/irradiation especially high-energy heavy ion irradiation are discussed, and several typical examples on simulation of radiation effects in reactor candidate structural materials using high-energy heavy ion irradiations are introduced. Experimental results and theoretical analysis suggested that irradiation with energetic particles especially high-energy heavy ions is a very useful technique for simulating the evolution of microstructures and macro-properties of reactor structural materials.     

Comparison of total dose effects on SiGe heterojunction bipolar transistors induced by different swift heavy ion irradiation

The degradations in NPN silicon-germanium （SiGe） heterojunction bipolar transistors （HBTs） were fully studied in this work, by means of 25-MeV Si, 10-MeV C1, 20-MeV Br, and 10-MeV Br ion irradiation, respectively. Electrical parameters such as the base current （IB）, current gain （β）, neutral base recombination （NBR）, and Early voltage （VA） were investigated and used to evaluate the tolerance to heavy ion irradiation. Experimental results demonstrate that device degradations are indeed radiation-source-dependent, and the larger the ion nuclear energy loss is, the more the displacement damages are, and thereby the more serious the performance degradation is. The maximum degradation was observed in the transistors irradiated by 10-MeV Br. For 20-MeV and 10-MeV Br ion irradiation, an unexpected degradation in Ic was observed and Early voltage decreased with increasing ion fluence, and NBR appeared to slow down at high ion fluence. The degradations in SiGe HBTs were mainly attributed to the displacement damages created by heavy ion irradiation in the transistors. The underlying physical mechanisms are analyzed and investigated in detail.     

400 MeV/u碳离子打靶的屏蔽参数计算

为了给医用重离子加速器提供一种专用的快速计算屏蔽厚度或对蒙特卡罗模拟结果进行验证的方法。采用FLUKA程序完成了400 MeV/u碳离子打不同靶的屏蔽参数计算。首先研究了打厚靶(铁、水)产生的次级辐射场的角度分布及主要成分;接着给出了不同角度范围下周围剂量当量在屏蔽体中的衰减曲线,通过拟合数据进一步得到不同角度范围下的辐射源项值H₀和衰减长度λ₀;最后结合莆田市医用重离子加速器治疗室的屏蔽设计,介绍了此套屏蔽参数的使用方法,通过与蒙特卡罗模拟结果的对比,证明了这套屏蔽参数的可靠性。该参数可为同类医用重离子加速器的屏蔽设计提供可靠的参考数据。     

重离子束在医学治疗中的应用

重离子束治癌是重离子束在医疗领域中的一项典型的应用技术,文章从重离子束在物理学与生物学上的特点,描述了它对肿瘤治疗具有优越性,物理剂量深度分布在射程末端有一个能量沉积集中区,其深度和大小均可调节;在靶区的相对生物效率（RBE）高、氧增比（OER）低;射程歧离与横向散射小;利用正电子发射断层照相（PET）技术术可以实时在线监测;可以三维扫描进行适用形治疗,半致死损伤修复小;辐射敏感性不依赖细胞周期相,文章还介绍了这项技术的国内外进展,并对其未来进行了展望。     

辐照前处理木质纤维素的研究进展

本文对几种主要的辐照前处理木质纤维素方法的效果和特点进行较为全面的比较和总结,旨在阐述微波、紫外线、γ射线、X射线、电子束、离子束等方式辐照前处理木质纤维素对其结构改变的机理尤其重点探讨了重离子辐照前处理引起木质纤维素同质异形体（I_α → I_β）的转换机制。木质纤维素结晶度与酶消化率呈强相关性,重离子辐照前处理可使木质纤维素中木质素和半纤维素部分破坏,导致其相对结晶度增加,从而增强了纤维素酶与木质纤维素的可及度,提高了酶解产率。因而,通过适当剂量的重离子辐照前处理可以显著提高酶对木质纤维素的生物转化效率和还原糖的产量,这为辐照前处理提高木质纤维素的综合利用提供了理论指导。     

Neutron dose measurement in carbon ion radiation therapy at HIRFL (IMP)

For radiation protection purposes, the neutron dose in carbon ion radiation therapy at the HIRFL (Heavy Ion Research Facility in Lanzhou) was investigated. The neutron dose from primary 12C ions with a specific energy of 100 MeV/u delivered from SSC was roughly measured with a standard Anderson-Broun rem-meter using a polyethylene target at various distances. The result shows that a maximum neutron dose contribution of 19 mSv in a typically surface tumor treatment was obtained, which is less than 1% of the planed heavy ion dose and is in reasonable agreement with other reports. Also the γ-ray dose was measured in this experiment using a thermo luminescent detector.     

The use of recombination chambers at radiation therapy facilities

The paper presents an overview of the applications of recombination chambers for dosimetric measurements at radiotherapy facilities. The chambers were used at electron, proton and heavy ion accelerators, in the beam and in the vicinity of the accelerators at very different dose rates. The examples of measurements discussed in the paper include: the determination of the absorbed dose and radiation quality parameters of a 170 MeV proton beam and BNCT (boron neutron capture therapy) beam, neutron dose measurements at a phantom surface outside the beam of a 15 MV electron medical accelerator, determination of ambient dose equivalent, H1 (10) outside the irradiated phantom in the proton therapy treatment room at JINR (Dubna, Russia), and at working places outside the shielding of the heavy ion therapy facility at GSI (Darmstadt, Germany).     

Measurement of the decay and time-resolved spectra of the emission from σ-excitons in KBr in the nanosecond range,produced by heavy-ion irradiation

While energetic heavy ions are currently in increasing use in solid state physics, radiation chemistry and biology, there is still little experimental information regarding the primary physicochemical processes. These high LET (linear energy transfer) ion particles injected into condensed matter produce short life-intermediates such as excited states, ions, and radicals, at high density along the track. The density effect of these intermediates may cause damage-formation and chemical reaction to yield different results compared with low LET radiation (γ, X-ray) or photo-irradiation. Electronically excited states, among the above intermediates, are thought to be especially important precursors. Measurements of the decay and time-resolved spectra of the emission are expected to give useful information regarding the radiation action of heavy ions. The measurements were done using a KBr single crystal at 4.2 K. We reported previously [1] that heavy ion irradiated KBr results in an extraordinarily large ratio of σ-emission to π-emission 2 intensity (～ 5 times larger than in the X- or electron-irradiation). This large ratio is, as was ascertained previously, not due to apparent processes such as temperature increase of a track but to intrinsic processes which will be discussed here.     

Angular distribution of Cherenkov radiation from relativistic heavy ions taking into account deceleration in the radiator

Numerical methods are used to study the dependence of the structure and the width of the angular distribution of Vavilov-Cherenkov radiation with a fixed wavelength in the vicinity of the Cherenkov cone on the radiator parameters (thickness and refractive index), as well as on the parameters of the relativistic heavy ion beam (charge and initial energy). The deceleration of relativistic heavy ions in the radiator, which decreases the velocity of ions, modifies the condition of structural interference of the waves emitted from various segments of the trajectory; as a result, a complex distribution of Vavilov-Cherenkov radiation appears. The main quantity is the stopping power of a thin layer of the radiator (average loss of the ion energy), which is calculated by the Bethe-Bloch formula and using the SRIM code package. A simple formula is obtained to estimate the angular distribution width of Cherenkov radiation (with a fixed wavelength) from relativistic heavy ions taking into account the deceleration in the radiator. The measurement of this width can provide direct information on the charge of the ion that passes through the radiator, which extends the potentialities of Cherenkov detectors. The isotopic effect (dependence of the angular distribution of Vavilov-Cherenkov radiation on the ion mass) is also considered.     

Reactive scattering damage to DNA components by hyperthermal secondary ions

We have observed reactive scattering damage to fundamental DNA building blocks by the type of hyperthermal secondary ions that are produced along heavy ion tracks in biological media. Reactions include carbon abstraction by N+, and hydrogen abstraction by O- and N+, at collision energies down to 1 eV. Our results show that localized reactive scattering by hyperthermal secondary fragments can lead to important physicochemical damage to DNA in cells irradiated by heavy ions. This suggests a fundamentally different picture of nascent DNA damage induced by heavy ion tracks, compared to conventional (x or gamma) radiation tracks.     

Lunar soil as shielding against space radiation

We have measured the radiation transport and dose reduction properties of lunar soil with respect to selected heavy ion beams with charges and energies comparable to some components of the galactic cosmic radiation (GCR), using soil samples returned by the Apollo missions and several types of synthetic soil glasses and lunar soil simulants. The suitability for shielding studies of synthetic soil and soil simulants as surrogates for lunar soil was established, and the energy deposition as a function of depth for a particular heavy ion beam passing through a new type of lunar highland simulant was measured. A fragmentation and energy loss model was used to extend the results over a range of heavy ion charges and energies, including protons at solar particle event (SPE) energies. The measurements and model calculations indicate that a modest amount of lunar soil affords substantial protection against primary GCR nuclei and SPE, with only modest residual dose from surviving charged fragments of the heavy beams.