The hyper-radiosensitivity effect of human hepatoma SMMC-7721 cells exposed to low dose gamma-rays and C-12 ions

Hypersensitive response of mammalian cells in cell killing to X- and gamma-rays has been reported at doses below 1 Gy. The purpose of this study was to examine the low dose sensitivity of human hepatoma SMMC-7721 cells irradiated with Co-60 gamma-rays and 50 MeV/u C-12 ions. Experiments using gamma-rays and charged particle irradiation were performed, particularly in the low dose range from 0 to 2 Gy. The survival effect of SMMC-7721 cells was measured by means of standard clonogenic assay in conjunction with a cell sorter. The result indicates SMMC-7721 cells showed hyper-radiosensitive response at low doses and increased radio-resistance at larger single doses for the carbon ions (LET = 45.2 keV/mu m) and the gamma-rays. However, the HRS/IRR effect caused by high-LET irradiation is different from that by low-LET radiation. This might possibly be due to the difference in the mode of energy deposition by particle beam and low-LET irradiation.

Evaluation of sex specificity on oxidative stress induced in lungs of mice irradiated by C-12(6+) ions

The aim of this work is to identify if there is sex specificity on C-12(6+) ion-induced oxidative damage in mouse lung at different time points. Kun-Ming mice were divided into two groups, each composed of six males and six females: control group and irradiation group with a single acute dose of 4 Gy. Animals were sacrificed at 2, 4 and 12 h respectively, there lungs were removed immediately, and the oxidative stress-related biomarkers were measured by Diagnostic Reagent Kits. The results showed that the relative activities of superoxide dismutase (4 h), catalase (2 h) and Se-dependent glutathione peroxidase (12 h) have significant changes (P < 0.05) between male groups and female groups, suggesting that the lungs of male mice are more sensitive to counteracting the oxidative challenge. Moreover, higher levels of malondiadehyde and lower contents of glutathione were also found in males, indicating that oxidative stress induced by C-12(6+) ion is pronounced in the lungs of males. We thought that these sex-responded differences may be attributed to the influence of sex hormones.

两种保护剂对C离子诱导小鼠急性肝损伤的应答；Response of Two Protective Agents to Acute Injury Induced by ~(12)C~(6+) Ions in Mouse Liver

比较了N-乙酰半胱氨酸(NAC)及乙酰左旋肉毒碱(ALCAR)对12C6+离子照射小鼠的损伤效应,并探讨了其可能的作用机制。利用4Gy剂量的12C6+离子束对预先给予NAC(100mg/kg)和ALCAR(100mg/kg)保护的昆明小鼠进行单次全身照射。随后检测肝组织中总抗氧化能力(TAC)、DNA单链断裂和细胞凋亡率。结果显示,与照射对照组相比,提前给予NAC和ALCAR均极显著地增强了肝组织的抗氧化能力(P<0.001),减轻了12C6+离子导致的肝组织中DNA断裂(P<0.001)和细胞凋亡(P<0.001)。此外,还发现ALCAR组抗重离子辐照损伤的能力显著地高于NAC组(P<0.05)。实验结果提示了NAC和ALCAR可通过抵御组织内的氧化胁迫,阻止DNA链的断裂和细胞的凋亡,实现对C离子辐照损伤的保护效应。而且ALCAR比NAC可能更适合成为有潜力、有希望的抗C重离子辐射药物。

阿佛曼链霉菌的~(12)C离子辐照效应及高产菌株选育；Research on Mutation Breeding of High-producing Strains from Streptomyces Avermitilis Irradiated by Ion Beam of ~(12)C~(6+)

选用12C6+离子辐照诱变阿维菌素B1a产生菌ZJAV-A1,研究其诱变效应。实验结果表明,12C6+离子辐照剂量50Gy时致死率97%,正突变率最高可达到34.2%。通过12C6+离子诱变处理,结合平板培养基及斜面培养基的正突变菌株筛选,最终获得一株稳定性良好,阿维菌素B1a组分产量稳定在4460—4588μg/ml之间,较出发菌株提高11.1%—14.7%的突变株ZJAV-Y1-203。

Early effects of low dose C-12(6+) ion or X-ray irradiation on human peripheral blood lymphocytes

The aim of this study was to estimate the acute effects of low dose C-12(6+) ions or X-ray radiation on human immune function. The human peripheral blood lymphocytes (HPBL) of seven healthy donors were exposed to 0.05 Gy C-12(6+) ions or X-ray radiation and cell responses were measured at 24 h after exposure. The cytotoxic activities of HPBL were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT); the percentages of T and NK cells subsets were detected by flow cytometry; mRNA expression of interleukin (IL)-2, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma were examined by real time quantitative RT-PCR (qRT-PCR); and these cytokines protein levels in supematant of cultured cells were assayed by enzyme-linked immunosorbent assays (ELISA). The results showed that the cytotoxic activity of HPBL, mRNA expression of IL-2, IFN-gamma and TNF-alpha in HPBL and their protein levels in supernatant were significantly increased at 24 h after exposure to 0.05 Gy C-12(6+) ions radiation and the effects were stronger than observed for X-ray exposure. However, there was no significant change in the percentage of T and NK cells subsets of HPBL. These results suggested that 0.05 Gy high linear energy transfer (LET) C-12(6+) radiation was a more effective approach to host immune enhancement than that of low LET X-ray. We conclude that cytokines production might be used as sensitive indicators of acute response to LDL (C) 2009 COSPAR. Published by Elsevier Ltd. All rights reserved.

80 MeV/u C-12离子诱变选育PHB高产菌株；A strain of high PHB output by mutagenesis of 80 MeV/u C-12 ions

用80MeV/u12C6+离子对一株积累聚β-羟基丁酸酯(PHB)的芽孢杆菌(BacillusP-9)进行诱变选育,最终获得PHB高产株菌G15,其PHB产量达2.93g/L,与出发菌株相比较,PHB积累量提高了1.5倍。研究结果表明,本试验辐照最佳剂量为15Gy。重离子辐照诱变育种效果显著,具有广阔的发展应用前景。

Measurement of the total reaction cross section for the mirror nuclei N-12 and B-12

The mirror nuclei N-12 and B-12 are separated by the Radioactive Ion Beam Line in Lanzhou (RIBLL) at HIRFL from the breakup of 78.6 MeV/u N-14 on a Be target. The total reaction cross-sections of N-12 at 34.9 MeV/u and B-12 at 54.4 MeV/u on a Si target have been measured by using the transmission method. Assuming N-12 consists of a C-11 core plus one halo proton, the excitation function of N-12 and B-12 on a Si target and a C target were calculated with the Glauber model. It can fit the experimental data very well. The characteristic halo structure for N-12 was found with a large diffusion of the protons density distribution.

Experimental Study on the Exotic Structure of N-12 in RIBLL

We measured the total reaction cross sections of N-12 in Si at 36.2 MeV/u. using Radioactive Ion Beam Line in Lanzhou (RIBLL) with a new method. The reaction target was installed at the intermediate focusing point T1 at RIBLL. This scheme allows us to identify particles before and after the reaction target unambiguously. The total reaction cross section (1760 +/- 78mb) of N-12 in Si is obtained. Assuming that N-12 consists of a core C-11 plus one halo proton, the excitation function of N-12 on the Si and C targets is calculated with the Glauber model and the Fermi-Fermi density distributions. It can fit the experimental data very well. A large diffusion of the protons density distribution supports the halo structure for N-12.

~(12)C与~(209)Bi反应中Au同位素的产额与Q_(gg)的关系；Q_(gg)-Yield Dependence of Au Isotopes in Interaction of 47 MeV/u ~(12)C With ~(209)Bi

用47MeV/u12C离子轰击天然铋靶,通过炮弹和靶核之间的核子转移反应产生Au同位素。使用放射化学方法从大量Bi和复杂反应产物中分离、纯化Au,并制备Au的γ射线测量源。使用HPGe探测器测量放射性Au同位素的γ活性。根据照射结束时Au同位素的活度和其他相关数据,确定每个Au同位素的产生截面。分析发现,缺中子Au同位素的产生截面与Qgg值之间不遵从指数依赖关系,这可用重离子碰撞中的次级过程加以解释。

~(12)C离子束辐照对酵母发酵能力的影响；Improved ethanol fermentation of a yeast mutant by C-12 ion beam irradiation

利用100MeV/u的12C6+离子束辐照酵母Saccharomyces cerevsiea YY,选育出一株高产突变菌株C03A,考察C03A发酵过程中不同温度、pH、糖汁浓度对发酵的影响。通过正交实验确定最佳发酵条件为:糖汁浓度24%、温度35℃、pH5.0。在10L发酵罐实验中,C03A发酵速率相对原始菌株高,36h发酵完全,比原始菌株缩短12h;发酵产酒率达到13.2%(V/V),比原始菌株高1.6%(V/V)。

~(12)C~(6+)离子束辐照紫苏干种子当代效应；Effects of Irradiation with ~(12)C~(6+) Ions on M1 Characters of Perilla frutescens(L.) Britt

利用兰州重离子研究装置(HIRFL)提供的12C6+离子束辐照紫苏干种子(辐照剂量为40,80和120Gy,剂量率4Gy/min),探讨了重离子束辐照对紫苏M1代的生物学效应。结果发现,经不同剂量的12C6+离子束辐照后,紫苏种子的发芽率、发芽势、存活率、株高、分枝数、单株产量和千粒重等生物学性状均发生了变化,其中发芽势、单株产量和千粒重随辐照剂量的提高而降低,且有明显的剂量效应关系,但发芽率、大田成活率、株高和分枝数却随辐照剂量的增大,呈现出明显的"抛物线"趋势;紫苏幼苗根尖细胞的微核率和染色体畸变率随辐照剂量增加呈线性增加关系。这表明:12C6+重离子束辐照紫苏种子,具有明显的当代损伤效应,在本试验剂量范围内,低剂量辐照对发芽率和成活率有促进作用。

~(12)C~(6+)高能重离子辐照大葱损伤及其分子生物学效应；Cytological Damage and Molecular Biology Effect of ~(12)C~(6+) Heavy Ions on Allium fistulosum L.

利用30,90,180Gy3种剂量的12C6+重离子束辐照大葱种子,研究其在细胞水平和农艺性状的诱变效应并进行RAPD分析。通过与M1代的研究结果比较后表明:经过不同剂量12C6+重离子照射后能有效地诱导大葱细胞形成微核和染色体畸变,这种诱变效应,在M2代仍然有所表现。M1代大葱结果期的株高、白长、花序直径和种子产量随辐照剂量增加产生明显差别,其中30Gy辐照组增幅最大。大葱总水溶性蛋白质和维生素C的含量在30Gy组中积累最多,在90Gy组有明显下降。与M1代一致,M2代中大葱染色体微核率及RAPD分析所得的DNA多态性比率仍然与辐照剂量呈正相关,但比率整体下降;说明高能量重离子辐照造成的DNA变异在M2代被修复和淘汰。

（一）兰州重离子加速器束流能量、能散测量（二）中能~(12)C + ~(64)Ni, ~(58)Ni碎裂反应的实验研究

本论文通过讨论选择了简单易行的弹性散射法来测量兰州重离子加速器流能量、能散，描述了整个实验的准备、进行及数据处理，并讨论、修正了所得的实验结果，得到了~(12)C束流能散为(2.74 ± 0.14) * 10~(-2)，能量经刻度为每核子46.4MeV/u。本工作还拟采用飞行时间法来测量束流能量的绝对值，以检验弹性散射法测得的能量值，而且已设计制作了用作起始探测器的微道板（MCP）零时探测器，上器进行了必要的高调试，用MCP零时探测器作为起始探测器，Si半导体探测器作为终止探测器，对于10MeV/uα粒子，得到了好于560ps的总时间分辩，完全可用于中能重离子实验探测

42 MeV/u~(12)C与~(115)In反应的靶余核

本实验使用放射化学方法测定了42 MeV/u (12)C与~(115)In相互作用靶余核的生成截面。借助高斯电荷分布的假设得到了靶余核的质量分布。将实验得到的质量分布与熔合碎裂模型和级联的两体衰变模型进行了比较。特别值得注意的是，使用统计的两体衰变模型Monte Carlo GEMINI程序计算第一次与实验结果符合得非常满意。同时计算结果也表明：在42MeV/u的轰击能量下，完全熔合对靶余核的产物仍然有很大的贡献。在同样的假设下，得到了靶余核的同位素分布。可以看到，同位素分布的宽度随靶余核原子序数的增加而增加，在此对利用中能重离子反应生成新的远离β稳定线的缺中子核素进行了讨论

46.7 MeV/u~(12)C轰击~(58)Ni、~(115)In、~(197)Au反应中粒子发射研究中子皮及中子分布弥散度对核势的影响

用能量密度公式及小液滴模型给出的费米密度分布，并引入中子皮及中子分布弥散度随中子过剩自由度增加而增加这一因素，计算了重离子反应在相互作用势及熔合位垒。熔合位垒的计算值和实验值符合很好，特别是在中重核区域，改善了以前的计算结果。详细研究了亲近势标度，发现用中子皮及中子分布弥散度的变化能较好地解释中子过剩自由度对新近势标度偏离的影响。本工作对奇异核结构与核反应性质的研究无疑是有用的。我们利用HIRFL提供的46.7MeV/u ~(12)C束轰击~(58)Ni、~(115)In、~(197)Au研究了反应中发射的α粒子角分布和能谱。从速度表象中洛仑兹不变截面等高图中明显看到发射α粒子的三个源。用这三个源的运动模型成功拟合了α粒子能谱，所提取的参数符合费米气体模型计算结果，并讨论了能谱及拟合参数对靶的依赖关系。认为快速源实质上来自弹核碎裂或类弹核碎裂