二烯丙基二硫对12C6+离子束辐照损伤小鼠的保护作用研究

研究大蒜素重要活性成分二烯丙基二硫( Diallyl disulfide, 简称DADS) 对12C6+离子束辐照损伤小鼠的保护作用。利用4 Gy 剂量12C6+离子束对不同浓度DADS 预处理的雄性昆明小鼠进行单次全身照射。随后检测骨髓细胞微核率和肝组织中丙二醛(MDA) 含量、蛋白质总羰基含量、总抗氧化能力( TAOC)及谷丙转氨酶(ALT ) 活性。结果显示,与单纯照射组相比,低浓度DADS 预处理组骨髓细胞微核率和肝组织ALT 活性均显著降低(p<0.001),而肝组织T-AOC明显增强( p < 0.05 );中浓度DADS 预处理组肝组织中MDA 含量和蛋白质总羰基含量均显著减少( p < 0.05 )。结果提示,DADS通过抑制氧化应激,有效地保护了脂质、蛋白质和遗传物质免受12C6+离子束辐照引起的损伤。The radioprotective effect of Diallyl disulfide (DADS) on 12C6+ ion irradiation was studied. Pretreated with DADS of different concentration, male Kung-Ming mice were exposed to whole body irradiation with dosage of 4 Gy 12C6+ ion. The animals were sacrificed after irradiation. Then the bone marrow cells micronucleus rate, malondialdehyde (MDA) levels, content of protein carbonylation, total antioxidant capacity ( T-AOC) and alanine aminotransferase ( ALT ) activity were measured. As compared with those in irradiated group, the ratio of micronucleus cells in marrow and the hepatic ALT activity in the pretreatment group with low dose DADS decreased significantly ( p < 0.001 ). Similarly,the content of protein carbonylation and the levels of MDA droped dramatically in the group with middle dose DADS treatment ( p < 0.05 ). On the contrary, the hepatic T-AOC increased markedly in the group of pretreatment with low dose DADS ( p < 0.05 ). The results showed that DADS protect lipoid, protein and genetic material from 12C6+ ion irradiation by right of resisting oxidative stress.     

~(12)C~(6+)离子束辐照紫苏干种子当代效应

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。     

12C6+离子束辐照番茄种子当代效应

利用辐射能量为80 MeV/u 的12C6+重离子束辐照番茄种子, 辐照剂量分别为30, 60, 90, 120和160 Gy研究其对番茄M1代的生物学效应。结果表明, 随着辐照剂量的增大, 番茄的发芽率和成苗率降低, 且成苗率明显低于发芽率, 发现辐照损伤主要抑制了根的生长; MDA和脯氨酸含量变化的总体趋势为随着辐照剂量的增大先升后降再升高, 说明高剂量C离子辐照对生物膜造成更严重的损伤; APX活性随着辐照剂量的增大呈先升后降再升高的趋势, 表明APX在清除活性氧中起主要作用; POD和SOD活性的总体趋势是随着辐照剂量的增大而降低, 且明显低于对照组。综合分析表明, 12C6+重离子束辐照番茄种子, 对M1代具有明显的损伤效应, 高剂量辐照对番茄种子造成的损伤更大, 使酶的活性降低, 抑制植株生长。 To investigate the M1 biological effects of heavy ions irradiation on Lycopersicon esculentum Mill., its seeds were irradiated by 12C6+heavy ions (80 MeV/u) with the dosages of 30, 60, 90, 120 and 160 Gy respectively . The results showed that with doses increased gradually, germination rate and seedling rate of Lycopersicon esculentum Mill. were decreased, and the latter was lower than the former, mainly due to the inhibition of root growth. The irradiation increased the content of MDA and proline evidently, showing irradiation could damage biomembrane, and also decreased the activities of POD and SOD with distinct inhibition pattern. However, the low dose and high dose irradiation promoted APX activity, illustrating APX was induced to protect irradiation injury. In brief, exposure to 12C6+ heavy ions had obvious injury effects on the seeds of Lycopersicon esculentum Mill.. Heavy ions irradiation damaged biomembrane, inhibited activities of enzymes, and finally inhibited the growth of the first generation of these seeds.     

12C6+离子束辐照菘蓝干种子当代效应

利用兰州重离子研究装置(HIRFL) 提供的12C6+ 离子束辐照菘蓝干种子(辐照剂量为10,35,60,90 和140 Gy,剂量率20 Gy/min),探讨了重离子束辐照对菘蓝M1代的生物学效应。研究发现,不同剂量的12C6+ 离子束辐照后,菘蓝种子的发芽率、成苗率、株高、根长和根冠比等生物学性状以及对菘蓝中靛玉红和4(3H) 喹唑酮含量均发生了变化,其中株高和根长随辐照剂量的增加而降低;菘蓝叶和根中的4(3H) 喹唑酮和靛玉红的含量随辐照剂量增加呈马鞍形增加关系。这表明:12C6+ 重离子束辐照菘蓝种子具有明显的当代损伤效应, 并可显著提高菘蓝中靛玉红和4(3H) 喹唑酮的含量,其辐照适宜诱变剂量为35 Gy。To investigate the M1 biological effects of heavy ions on Isatis indigotica Fort, its dry seeds were irradiated by 12C6+ beam with the dose of 0, 10, 35, 60, 90 and 140 Gy respectively,at the rate of 20 Gy/min delivered by the Heavy Ion Research Facility in Lanzhou (HIRFL). The results showed that biological characters such as germinating rate, germinating potential, survival rate, plant height, root height and root-shoot ratio were changed after irradiation. Moreover, the plant height and root height decreased in a dos dependent manner. The indirubin and 4(3H) quinazolinone content of Isatis indigotica Fort was improved and exhibited obviously “saddle” trends with irradiation dose increasing.Data suggest that exposure with low-dose 12C6+ to seeds of Isatis indigotica Fort has obvious injury effects at the first generation, and the active ingredient content of Isatis indigotica Fort may be improved by carbon ion beamirradiation. It is concluded that the suitable irradiation dose of mutation breeding is 35 Gy for the seeds of Isatis indigotica Fort.     

轻中等质量核非对称裂变研究的新进展

介绍了轻中等质量核非对称裂变研究的新进展.通过对64,58Ni+12C和78,82,86Kr+12C反应复杂碎片的激发函数测量,发现流行的转动液滴模型和转动有限力程模型均不能复现实验的非对称裂变位垒数据.The excitation functions were measured for complex fragments with atomic number Z=4—25 emitted from the compound nuclei~(70,76)Se and~(90,94,98)Mo produced in the reactions~(64,58)Ni+~(12)C and~(78,82,86)Kr+~(12)C. The extracted mass asymmetric fission barriers have been compared with those calculated from macroscopic nuclear models.     

~(12)C~(6+)离子束与电子束辐照对薰衣草当代诱变效应的比较

采用100 MeV的~(12)C~(6+)离子束和1.2 MeV的电子束辐照薰衣草干种子,研究了2个品种的薰衣草干种子对不同辐射源的辐照生物学效应,以期找到薰衣草干种子的最佳诱变参数。结果表明:不论是薰衣草701还是702,经~(12)C~(6+)离子辐照后,其发芽率表现为先增大后减小的趋势;经电子束辐照后,发芽率随着剂量的升高而降低,电子束辐照后的发芽率要低于~(12)C~(6+)离子束。另外,2个品种的薰衣草经~(12)C~+离子辐照后,其胚轴胚根长度以及幼苗鲜重也较电子束辐照后的大。由此可知,重离子的辐照效果优于电子束的,有利于后期筛选出新的薰衣草突变株。     

12C6+ 离子束辐照对大鼠离体主动脉环内皮依赖性舒张功能的影响

利用兰州重离子研究装置(HIRFL) 提供的高能12C6+离子束(能量为300 MeV/u,剂量率为0.5 Gy/min) 辐照大鼠离体胸主动脉环,考察了12C6+离子束辐照对主动脉环内皮依赖性舒张功能的影响,并采用NBT 还原法测定血管环生成超氧阴离子(O2􀀀) 水平,加入外源性超氧化物歧化酶(SOD) 干预探讨了O2􀀀在内皮功能损伤中的作用。研究结果表明,2.0,4.0 和6.0 Gy 的12C6+离子束辐照大鼠胸主动脉环后,可致血管内皮依赖性舒张功能的剂量依赖性明显受损(P <0.01 vs control group),并可致血管环NBT 还原能力剂量依赖性增加(4.0 Gy 时,P <0.05;6.0 Gy 时,P <0.01 vs control group)。辐照前加入外源性SOD 对6.0 Gy 12C6+离子束辐照所致血管环NBT 还原能力升高有明显抑制作用(P <0.01),对血管环内皮依赖性舒张功能也有明显的保护作用(P<0.01),但辐照后10 min 加入外源性SOD,其保护作用明显不及前者。结论显示,12C6+ 离子束辐照大鼠胸主动脉环可致血管内皮功能受损,O2 清除剂SOD 对内皮功能受损有保护作用,说明O2􀀀介导了辐照所致内皮功能损伤。Heavy ion beam has many characteristics,and it is expected to be the most suitable radiation therapy technique for malignant tumor. It is lack of depth-understanding on the potential adverse reactions caused by using this technique, because heavy ion radiotherapy is applied to clinical for a short time. Studies have shown that the vascular injury plays a pivotal role in normal tissue damage induced in the conventional radiation therapy, but there was no research report on heavy ion beam irradiation-induced vascular injury. In the present study, the isolated aortic rings of rats were irradiated by 12C6+ ion beam (300 MeV/u, 0.5 Gy/min) delivered by HIRFL(Heavy Ion Research Facility in Lanzhou), the effects of 12C6+ ion beam irradiation on aortic rings with endothelium dependent diastolic function have been investigated.NBT reduction method was used for assaying the vascular ring formation of superoxide anion (O2􀀀) level, and the involvement of superoxide anion in endothelial function injury in rats was investigated through the intervention test of exogenous superoxide dismutase (SOD) on O2. The results showed that, the vascular endothelial dependent vasodilation was impaired significantly (P < 0:01 vs control group) by irradiation with 2.0, 4.0 and 6.0 Gy 12C6+ ion beam in a dosedependent manner, and the NBT reduction of vascular rings increased dose-dependently (P <0.05 at 4.0 Gy, P <0.01 at 6.0 Gy vs control group). Adding exogenous SOD before irradiation could significantly inhibit the increasing of NBT reduction (P<0.01), and also had protective effect on vascular endothelium dependent diastolic function (P<0.01), but 10 min after irradiation with exogenous SOD, its protective function was significantly less than before. Conclusion indicated that 12C6+ ion beam irradiation could cause endothelial function impaired, O2􀀀 scavenger SOD has a protective effect on endothelial dysfunction, suggesting that O2􀀀 mediates endothelial injury induced by heavy ion irradiation.     

12C6+离子辐照对4种农作物种子出苗率

以能量为80 MeV/u的12C6+离子为诱变源辐照油菜、 胡麻、 大葱和兵豆的干种子后, 研究了不同剂量处理对4种农作物M1和M2代种子出苗率及幼苗生长的影响。 实验结果表明: 重离子所导致的M1代生物学效应因不同的物种而表现出一定的差异, 适当剂量C离子辐照促进了油菜和胡麻M1代出苗率和幼苗的生长; 而不同剂量的C离子辐照抑制了大葱的出苗率和幼苗的生长; 兵豆3个剂量下的出苗率和对照相差很小, 但90 Gy辐照有利于其生长。 到了M2代, 4种作物辐照组的发芽率都低于各自的对照组; 30 Gy剂量下的油菜、 胡麻和兵豆长势最好; 大葱依然是对照的长势最好。 Crops of Brassica napus L., Linum usitatissmum L., Allium fistulosum L. and Lens culinaris Medic. were irradiated by 80 MeV/u 12C6+ ion beams with doses of 30, 90 and 180 Gy. The germination rates and heights of seedlings of M1 and M2 generation of these four plants were studied. The results indicated that germination rates and average heights of the B. napus and L. usitatissmum were improved by appropriate dose treatment, while great suppression was found in the irradiated groups of the A. fistulosum. As far as the L. Culinaris was concerned, little differences was observed on M1 germination rate, but the 90 Gy irradiation was favorable to growth of plant. The treatments with 30, 90 and 180 Gy were inferior to contrast one on M2 germination rate of the four species. Seedlings of M2 generation of the B. napus, L. sitatissmum and L. culinaris under 30 Gy grew better than the other groups, while the best performance of the A. fistulosum was shown by the control group.     

酵母β-葡聚糖对C离子辐射损伤小鼠免疫系统的防护作用

用12C6+离子束对小鼠进行一次性全身辐照, 检测不同剂量的酵母β-葡聚糖对12C6+辐射损伤小鼠免疫系统的防护作用。 辐照后观察小鼠的体重、 毛色及行为变化, 照后第2天和第7天检测小鼠外周血中白细胞含量, 照后第8天检测小鼠胸腺和脾脏内SOD, GSH PX活性和MDA含量。 实验结果表明, 给予酵母β 葡聚糖能减缓辐照引起的小鼠体重急剧下降, 增加小鼠外周血中白细胞含量,不同程度地恢复胸腺和脾脏SOD和GSH PX活性, 降低胸腺和脾脏MDA含量。 表明酵母β-葡聚糖对12C6+引起的小鼠辐射损伤具有防护作用。 To detect Yeast β-glucan’s protective effect on mice’s immune system after C ion beam radiation, mice were used as the test model. We observed the weight, hair color and behavior of mice everyday within a 7 d period of time after irradiation. Meanwhile, the content of white blood cell, on the 2nd and 7th day after irradiation was detected. We detected the thymus and spleen SOD, GSH PX activity and MDA content of the mice on the 8th day. The results showed that yeast β glucan could reduce the rapid weight loss of mice, increase white blood cell content, increase thymus and spleen SOD, GSH PX activity, decrease MDA content of thymus and spleen. These results indicate that yeast β glucan can protect mice’s immune system against C ion beam radiation damage.     

~(12)C~(6+)高能重离子辐照大葱损伤及其分子生物学效应

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。     

~(12)C~(6 )离子辐照小鼠Lewis肿瘤的研究

研究了HIRFL提供的12C6 离子辐照C57BL/6J小鼠右后腿移植的Lewis肿瘤的生长延迟和碳离子辐照对Lewis肿瘤小鼠寿命的延长.结果表明,碳离子照射的小鼠肿瘤生长体积明显地小于对照的体积.在剂量相同、分次数辐照越多时,肿瘤生长就越缓慢,肿瘤抑制就越高.在辐照分次数相同时,不同剂量对受照肿瘤生长体积未产生差异.在4Gy×3,8Gy×3和12Gy×2组3种辐照剂量下,小鼠寿命的P值小于0.05;可知小鼠的寿命延长具有统计学意义.     

12C6＋离子辐照人胃癌细胞系BGC823的氧效应研究

氧效应; 碳离子; 人胃癌细胞系BGC823 ;兰州重离子加速器     

碳离子辐照对人肺癌细胞A549细胞周期进程的影响

选取对数生长期人肺癌细胞A549接受0—6.0 Gy 碳离子照射， 用克隆形成法检测细胞的存活率； 并于照射后12和24 h收集细胞， 用流式细胞术检测细胞周期各时相的细胞百分比， 观察不同剂量碳离子辐照对A549细胞周期进程的影响。 结果显示: 0—6.0 Gy 碳离子照射后细胞存活率显著下降； 照射后12 h细胞发生G0/G1期阻滞， 而照射后24 h， 1.0 Gy 照射组细胞在G0/G1期阻滞， 2.0—6.0 Gy 照射组细胞在G2/M期阻滞。 上述结果表明， 在A549细胞接受碳离子照射后的12 和24 h内， 1.0 Gy 照射可持续激活细胞G1期检查点， 而2.0—6.0 Gy 碳离子照射后其细胞周期进程是随时间变化的。 To investigate the effects of cell cycle progression of A549 cell induced by 12C6+ ion irradiation at different doses, the survival fractions of the A549 cells were determined by colony forming assay; cell cycles were analyzed by FACS at 12 h or 24 h after irradiation. The results showed that the percentage of survival in the A549 cells decreased with irradiation doses. Compared with control group， the percentage of the cells in G0/G1 phase significantly increased at 12 h after irradiation with different doses of 12C6+ ions. However， at 24 h after irradiation the percentage of the cells in G0/G1 phase significantly increased with 1.0 Gy 12C6+ ions， while the cells showed increasing percentage in G2/M phase with 2.0, 4.0 or 6.0 Gy 12C6+ ions. The results suggested that G1 cell cycle checkpoint was activated in 12—24 h after irradiation with 1.0 Gy 12C6+ ions， but after irradiation with 2.0—6.0 Gy 12C6+ ions， the cell cycle progression of the A549 cells changed with time.     

Measurement of the total reaction cross section for the mirror nuclei ~(12)N and ~(12)B

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

结晶紫内酯开环机理的￣（13）CNMR研究

报道了结晶紫内酯开环机理研究。通过测定开环前后及平衡混合物的￣（１３）ＣＮＭＲ谱，对结晶紫内酯开环形成的正碳离子结构及影响正碳离子稳定性因素进行了分析。利用开环前后及平衡体系的化学位移数据求得了平衡混合物中内酯态和正碳离子之间的平衡常数．对不同条件下结晶紫内酯开、闭环机制进行了讨论。     

Fusion, resonances and scattering in12C+12C reaction

The variation of fusion cross-section (σJ_fus) with energy in the¹²C+¹²C collision is linked to the underlying resonance phenomenon through the behavior of reaction cross-section (σ) of which σ_fus is taken as a part. The calculation of σ_fus is done through an energy-dependent imaginary potential in the optical model potential (OMP). Through dispersion relation, such an imaginary potential gives rise to energy-dependent real potential which is incorporated in the OMP. In our calculation, a form of potential for the nuclear part which has a soft repulsive in-built core is introduced based on similar works done earlier. The calculated results of σ_fus are used to explain the oscillatory structure, astrophysical S-factor and the decreasing trend at higher energies of the experimental σ_fus data in the case of¹²C+¹²C system with remarkable success. The potential used for fusion calculation is tested for fitting elastic scattering data at some energies and is found good in forward angles. Further improvement of the fitting of these data is obtained by incorporating a coupling potential in the surface region. About twenty resonances are observed in our calculation in the specific partial waves and some of them are found close to the experimentally identified resonances in¹²C+¹²C reaction. Thus, we provide an integrated and comprehensive analysis of fusion, resonance and scattering data in the best studied case of¹²C+¹²C reaction within the framework of optical potential model.     

内质网应激对碳离子辐照宫颈癌HeLa 细胞的影响

利用不同剂量的碳离子辐照二硫苏糖醇(2.5 mmol/L) 预处理的HeLa 细胞,探讨了内质网应激反应对碳离子辐照宫颈癌HeLa 细胞的影响。实验发现:与单独辐照组相比,二硫苏糖醇联合碳离子辐照后细胞的存活率下降,而凋亡率增加;二硫苏糖醇联合碳离子辐照加重了碳离子辐照引起的细胞周期阻滞;且联合辐照组的自噬被明显激活。结果表明,持续的内质网应激可改变宫颈癌HeLa 细胞对碳离子辐照反应,且二硫苏糖醇可能通过影响HeLa 细胞的自噬性细胞死亡通路发挥作用。To investigate the effect of endoplasmic reticulum stress on HeLa cells to 12C6+ ion irradiation,HeLa cells were pretreated with 2.5 mmol/L dithiothreitol and irradiated by 12C6+ ions with different doses.The results showed that, compared with IR alone, dithiothreitol combined with carbon ion irradiation caused HeLa cell survival decreased, and the apoptosis increased. Moreover, dithiothreitol and carbon ion radiation combination treatment led to a significant increase of G2/M phase, and autophagy was activated obviously in combination treatment group. The results imply that continuous endoplasmic reticulum stress can change the response of HeLa cells to 12C6+ irradiation, and dithiothreitol may affect HeLa cells through the autophagy cell death pathway.