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Biological effects of radioactive ~9C-ion beams on cells

Chinese Science Bulletin 2005年第11期50卷 1070-1075页

作者： WEIZengquan LIQiang A.Kitagawa T.Kanai M.Kanazawa y.furusawa E.Urakabe XIEHongmei ZHOUGuangming InstituteofModernPhysics ChineseAcademyofSciencesLanzhou730000China InstituteofModernPhysics ChineseAcademyofSciencesLanzhou730000China//NationalInstituteofRadiologicalSciencesChiba263-8555JapanCorrespondenceshouldbeaddressedtoWeiZengquan NationalInstituteofRadiologicalSciences Chiba263-8555JapanCorrespondenceshouldbeaddressedtoWeiZengquan

The distinguishing feature and current technique progress of tumor treatment with heavy-ion beams is introduced in the paper. Additional superiority to tumor treatment from a radioactive ion beam (RIB) is emphatically discussed. The experimental research of the radioactive 9C-ion beams aimed at tumor treatment at Heavy Ion Medical Accelerator in Chiba (HIMAC), National Institute of Radiological Sciences (NIRS), Japan is described in detail, La-eluding production of the beams, optimization of parameters, distribution of depth dose, survival effect of cell and comparison of RBE between 9C- and 12C-beams. Results show that under 40 mm thick Beryllium target and 10 mm thick aluminum degrader at full (5%) momentum acceptance, the production rate and purity of the produced 9C-beams are 9.07×10-6 and 82.88% respectively with the primary 12C-beams of 430 MeV/u and 1.8×109 pps. A uniform irradiation field with homogeneity up to 89.6% inside central area 10 mm in diameter is obtained by using spot scanning. In this case, the dose rate at the entrance is 0.5 Gy/h. In survival experiment of cells, the average relative biological effectiveness (RBE) of 9C-beams is 5.28 and 2.93 for 12C-beams in the region around Bragg peak. The RBE of 9C-beams is 1.8 times higher than that of 12C-beams. It indicates that cell-killing efficiency of 9C-beams is stronger than that of 12C-beams. 9C-beams are more efficacious for tumor treatment than 12C-beams.

关键词：生物学放射性粒子束参数优化生存能力肿瘤细胞治疗方法

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Enhanced cell-killing effect induced by a radioactive ~9C-ion beam at the depths around its Bragg peak and its biophysical mechanisms

Enhanced cell-killing effect induced by a radioactive ~9C-io...

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第十次中国生物物理学术大会

作者： y.furusawa M.Kanazawa A.Kitagawa National Institute of Radiological Sciences Chiba 263-8555Japan National Institute of Radiological Sciences Chiba 263-8555Japan National Institute of Radiological Sciences Chiba 263-8555Japan

＜正＞To evaluate the potential importance of a radioactive 9C-ion beam, representing a double radiation source coming from the external beam itself and the delayed particles emitted internally, in cancer therapy, radiobiological experiments using human salivary gland cells （HSG） were performed in the secondary beam line （SBL） at the Heavy Ion Medical Accelerator in Chiba （HIMAC）, Japan, where HSG cell surviving fractions were measured with standard clonogenic assay. An enhanced cell-killing effect at the penetration depths around the Bragg peak of the β-delayed particle decay 9C-ion beam has been observed in comparison with a therapeutic C beam under the same conditions, and RBE values of the 9C beam were revealed to be higher than those of the comparative 12C beam by a factor of up to 1.87. This means that radioactive 9C-ion beam has a significant advantage, killing cancerous cells more efficiently, in tumor therapy once its intensity meets the requirement of radiotherapy.

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放射性离子束^(9)C的细胞生物学效应

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科学通报 2005年第5期50卷 416-421页

作者：卫增泉李强 A.Kitagawa T.Kanai M.Kanazawa y.furusawa E.Urakabe 颉红梅周光明中国科学院近代物理研究所兰州730000 日本放射医学综合研究所

首先介绍了重离子束治癌的特点及当前的技术进步, 着重讨论了放射性离子束(RIB)在肿瘤治疗上增添的优势, 详细叙述了在日本放射医学综合研究所(NIRS)重离子医用加速器(HIMAC)上旨在肿瘤治疗的放射性离子束 C 的实验研究, 包括束流产生... 详细信息

首先介绍了重离子束治癌的特点及当前的技术进步, 着重讨论了放射性离子束(RIB)在肿瘤治疗上增添的优势, 详细叙述了在日本放射医学综合研究所(NIRS)重离子医用加速器(HIMAC)上旨在肿瘤治疗的放射性离子束 C 的实验研究, 包括束流产生、参数优化、深度物理剂量分布、细胞辐照后的存 9活效应以及 C 和 C 束的相对生物效率(RBE)比较. 最终结果: 在40 mm 厚铍靶、10 mm 厚铝降能器、 9 125%动量接收度时, 采用 430 MeV/u、1.8×109 粒子/s 的初试束 C, 得到的 C 束的产生率为 9.07×10?6, 12 9纯度为 82.88%, 采用点扫描技术时, 在直径为 10 mm 的中心面积内, 可获得均匀度为 89.6%的辐照场,这时在入口处的剂量率为0.5Gy/h. 在Bragg峰附近范围内的细胞存活实验中, C束的平均RBE为5.28, 9而 C 束的平均 RBE 为 2.93, C 束的 RBE 要比 C 束的高1.8 倍, 这显示 C 束在 Bragg 峰附近范围内, 12 9 12 9对细胞的杀伤力要比 C 强, 在肿瘤治疗上会更有效.

关键词：细胞生物学放射性离子束肿瘤治疗方法细胞存活效应

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双重辐射源9C束流在其Bragg峰区对细胞致死效应增强的生物物理机制

双重辐射源9C束流在其Bragg峰区对细胞致死效应增强的生物物理机制

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第二届全国反应堆物理与核材料学术研讨会

作者：李强 y.furusawa M.Kanazawa 金晓东闫铮中国科学院近代物理研究所日本国立放射线医学综合研究所

相对重离子束治癌用12C束流而言,β缓发粒子衰变放射性9C束流在其Bragg峰区附近深度上对细胞的致死效应明显增强已经在我们先前的实验中被发现,9C 束流的相对生物学效应(RBE)较12C束流要大一倍以上,显示了放射性束9C应用于治癌的美好前...

相对重离子束治癌用12C束流而言,β缓发粒子衰变放射性9C束流在其Bragg峰区附近深度上对细胞的致死效应明显增强已经在我们先前的实验中被发现,9C 束流的相对生物学效应(RBE)较12C束流要大一倍以上,显示了放射性束9C应用于治癌的美好前景。本文旨在探讨造成这一重要实验现象的生物物理机理。首先,建立模型计算了用于实验时产生的9C束流的阻止沉积几率密度分布,模型考虑了初始束流的动量分布,束流随贯穿深度增加由核反应导致的离子通量衰减和能量损失岐离等效应。发现9C束流对细胞致死效应增强的区域出现在入射9C离子的阻止沉积区域。其次,以9C束流入射处剂量为1Gy为例,根据计算得到的入射9C离子阻止分布几率密度推导了9C束流在不同贯穿深度上的沉积离子密度,进而得到了不同深度上每细胞内平均沉积9C离子数;同时,由相近剂量平均传能线密度(LET)深度上9C和12C束流实验上测得的细胞存活率推导出了9C及12C束流在这些深度上导致的每细胞平均致死事件数。发现:在照射剂量相同时每细胞平均沉积9C离子数与9C及12C束流每细胞平均致死事件数之差竞相吻合。因此本文认为一个沉积9C离子足以造成该细胞死亡。考虑到由9C衰变而发射低能粒子的性质,9C离子细胞中沉积必定在该细胞中造成团簇损伤,因而本文结果又可作为辐射团簇损伤高效细胞致死的间接证据。

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Unraveling the mystery of enhanced cell-killing effect around the Bragg peak region of a double irradiation source^(9)C-ion beam

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Chinese Science Bulletin 2005年第22期50卷 2546-2551页

作者： LI Qiang y. furusawa M. Kanazawa A. Kitagawa Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China National Institute of Radiological Sciences Chiba 263-8555. Japan

An enhanced cell-killing effect at the penetra- tion depths around the Bragg peak of a β-delayed particle decay 9C-ion beam has been observed in our preceding ra- diobiological experiments in comparison with a therapeutic 12C beam under the same conditions, and RBE values of the 9C beam were revealed to be higher than those of the comparative 12C beam by a factor of up to 2. This study is aimed at investigating the biophysical mechanisms underlying the important experimental phenomenon. First of all, a model for calculating the stopping probability density of the experimentally applied 9C beam is worked out, where all determinants such as the initial momentum spread of the 9C beam, the fluence attenuation with penetration depth due to the projectile-target nuclear reaction and the energy strag- gling effect are taken into account. On the basis of the calcu- lated 9C-ion stopping distribution, it has been found that the area corresponding to the enhanced cell-killing effect of the 9C beam appears at the stopping region of the incident 9C ions. The stopping 9C-ion density in depth, then, is derived from the calculated probability density. Moreover, taking entrance dose 1 Gy for the 9C beam as an example, the aver- age stopping 9C-ion numbers per cell at various depths are deduced. Meanwhile, the mean lethal damage events induced by the 9C and comparative 12C beams at the depths with al- most equal dose-averaged LETs are derived from the meas- ured cell surviving fractions at these depths for the 9C and 12C beams. Under the condition of the same absorbed doses, there are indeed good agreements between the average stop- ping 9C-ion number pre cell and the difference of the mean lethal damage events between the 9C and 12C beams at the depths of similar dose-averaged LETs. It can be inferred that if a 9C ion comes to rest in a cell, the cell would undergo dy- ing. In view of the decay property of 9C nuclide, clustered damage would be caused in the cell by the emitted low-

关键词：放射源细胞损伤离子分布致死因子离子束

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Continuous observation of twinning and dynamic recrystallization in ZM21 magnesium alloy tubes during locally heated dieless drawing

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Journal of Magnesium and Alloys 2022年第3期10卷 791-805页

作者： Peihua Du Shusaku furusawa Tsuyoshi Furushima Department of Mechanical and Biofunctional Systems Institute of Industrial ScienceThe University of Tokyo4-6-1KomabaMeguroTokyo 153-8505Japan

Compared to cold drawing,dieless drawing has shown great potential for manufacturing biodegradable Mg alloy microtubes due to the large reduction in area acquired in a single ***,owing to the local heating and local deformation,the deformation mechanism during dieless drawing is not clear,and thus causing difficulties in controlling the microstructure of dieless drawn *** the purpose of acquiring a desired *** this study the deformation mechanism of ZM21 Mg alloy tube was clarified by conducting continuous observation of the microstructural evolution during dieless *** results show that both SRX and DRX occurred during dieless *** occurred before the plastic deformation to soften dieless drawn *** increase of feeding speed,the deformation mechanism changed accordingly:(1) At the low-speed of 0.02 mm/s,the deformation mechanism was dominated by twin-slip sliding,during which {10-12} tension twins were generated inside grains to accommodate the plastic deformation by changing the crystal orientation.(2) At the intermediate-speed of 2 mm/s,a twin-DRX process related to {10-12} tension twin was observed,which was characterized by the generation of abundant {10-12} tension twins and the evolution of misorientation angle of {10-12} tension ***,the transformation from twin-DRX to CDRX can be observed at the late stage of plastic deformation,which was attributed to the inhomogeneous conditions of dieless drawing.(3) At the high-speed of 5 mm/s,a CDRX process was observed,during which grain boundary sliding and grain tilting were observed,in addition to the gradual rotation of *** results show that during dieless drawing,DRX is not only a temperature-dependent phenomenon,but also influenced by the variation of feeding speed.

关键词： Dieless drawing Inhomogeneous condition Twining Dynamic recrystallization Microstructure evolution Magnesium alloy Twinning

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Microstructure and performance of biodegradable magnesium alloy tubes fabricated by local-heating-assisted dieless drawing

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Journal of Magnesium and Alloys 2020年第3期8卷 614-623页

作者： Peihua Du Shusaku furusawa Tsuyoshi Furushima Department of Mechanical and Biofunctional Systems Institute of Industrial ScienceThe University of Tokyo4-6-1KomabaMeguroTokyo 153-8505

Magnesium(Mg)alloy stents are expected to be the next generation of stents because of good biocompatibility and *** with cold drawing,dieless drawing with local heating is an effective method for manufacturing the Mg alloy microtubes since a large reduction in area can be achieved in a single ***,the microstructure and properties of dieless drawn tubes have not been clarified,leading to the problems in practical application of dieless drawn *** this study,the microstructure and performance of dieless drawn tubes are *** results show that temperature and speed in the dieless drawing process are two factors in determining the grain size of dieless drawn tubes since decreasing the temperature or increasing the speed promotes the generation of fine-grained *** are also generated during the dieless drawing process,which 1)disintegrates grains leading to refinement and 2)causes Hall-Petch law effect on dieless drawn *** tests show that grain size is the main factor in determining the mechanical properties of dieless drawn tubes,namely,0.2%proof stress 135-180MPa,ultimate tensile strength(UTS)200-250MPa,and elongation 8-12%.In 0.9 wt%NaCl solution,localized corrosion is the key factor in initiating the corrosion of dieless drawn tubes,but refined grains and fewer twins can alleviate local *** results imply that dieless drawn tubes are promising in the clinical application of Mg alloy stents for cardiovascular disease.

关键词： Dieless drawing Magnesium alloy tube Microstructure Mechanical properties Corrosion properties

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Gene expression of CCL8 and CXCL10 in peripheral blood leukocytes during early pregnancy in cows

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Journal of Animal Science and Biotechnology 2018年第4期9卷 813-823页

作者： Ryosuke Sakumoto Kosuke Iga Ken-Go Hayashi Shiori Fujii Hiroko Kanahara Misa Hosoe Tadashi furusawa Division of Animal Breeding and Reproduction Research Institute of Livestock and Grassland Science National Agriculture and Food Research Organization (NARO) Division of Livestock and Forage Research Tohoku Agricultural Research CenterNARO Division of Animal Sciences Institute of Agrobiological SciencesNARO

Background: The aim of the present study was to evaluate CCL8 and CXCL10 expression and its regulatory mechanism in peripheral blood leukocytes(PBLs) at the time of maternal recognition in cows. Blood samples were collected on 14, 15, 16, 17 and 18 d after artificial insemination(AI). Based on the day of return of estrus, cows were divided into three groups, pregnant(n = 5), early embryonic mortality(EEM; n = 5) and late embryonic mortality(LEM; n = 5). The gene expression levels in PBLs were assessed with quantitative real-time reverse transcription ***: The expression of CCL8 and CXCL10 mRNA in PBLs gradually increased from 14 to 18 d of pregnant cows and significant differences were observed on 18 d(P yxovirus-resistance gene(MX) 1 and MX2 mRNA expression in PBLs increased from 14 to 18 d which was significant on 18 d of pregnant cows as well as in LEM cows(P y pregnancy-related substances or not, expression level was assessed after exposure to interferon-τ(IFNT) and CCL16. Monocytes, granulocytes and lymphocytes were obtained using density-gradient centrifugation and flow cytometry. The addition of IFNT(100 ng/mL) and CCL16(100 ng/mL) to cultured PBLs increased the expression of CCL8 and CXCL10 mRNA(P y IFNT and CCL16(P y pregnancy. Since IFNT stimulated CCL8 and CXCL10 expression in cultured PBLs, the increase of CCL8 and CXCL10 might be pregnancy-dependent *** expression of both CCL8 and CXCL10 in PBLs was stimulated by CCL16 as wel as IFNT, suggesting a chemokine interaction that at least includes CCL8, CXCL10 and CCL16, and m

关键词： CCL8 Cow CXCL10 Leukocytes Pregnancy

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Implications of double-stranded DNA structure for development, cancer and evolution

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Open Journal of Genetics 2011年第3期1卷 78-87页

作者： Mitsuru furusawa 不详

Genomes consist of DNA and the genetic information is encoded in a linear form of DNA. According to the central dogma of molecular biology, the genetic information is transcribed into mRNA, and mRNA translated into a polypeptide. Gene expression should be precisely regulated in order to create progeny. Unlike RNA, DNA has double-stranded structure. Is there any specific biological reason why DNA has evolved to possess double-stranded structure? In this presentation, biological implications of the double-stranded structure of the DNA molecule will be reviewed. In eukaryotes, it has been reported that cells might have the machinery that distinguishes one DNA-strand from the other, and that the strand-recognition mechanism might control development, cancer and evolution. Three prominent models concerning biological implications of replication of double-stranded DNA will be discussed: 1) Klar’s “somatic strand-specific imprinting and selective chromatid segregation model” for differential gene regulation, 2) Cairns’ “immortal strand inheritance model” for cancer prohibition, and 3) the “disparity mutagenesis model” for the acceleration of evolution proposed by the present author.

关键词： Blast Graph Theory Redundant Sequences CD-HIT

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Organic Solvent-Free and Simple Method for Determining Cyromazine and Its Metabolite, Melamine, in Cow’s Milk

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Journal of Analytical Sciences, Methods and Instrumentation 2012年第2期2卷 68-73页

作者： Naoto furusawa Graduate School of Human Life Science Osaka City University Osaka Japan

This paper described an organic solvent-free, rapid, simple, and space-saving method of sample preparation followed by HPLC coupled photo-diode array (PDA) detector for simultaneous quantification of cyromazine (CyR) and its decy-cropropylated metabolite, melamine (MEL), in milk. The HPLC-PDA was performed on an Inertsil? HILIC column with an isocratic aqueous mobile phase. Analytes were extracted from the sample using water, and purified by Mono-Spin?-C18, a centrifugal monolithic silica spin mini-columns, and quantified within 20 min. The method, performed under 100% aqueous conditions, obtained average recoveries for CyR and MEL in the range of 93.2% - 99.1% with relative standard deviations ≤ 2.8%. The quantitation limits were 8.5 ng/mL for CyR and 10 ng/mL for MEL, respectively. No organic solvents were used at any stage of the analysis.

关键词： Cyromazine Melamine HPLC-PDA Milk: Organic Solvent-free

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