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Tc solution from 
Mo to be obtained by (
) reaction; A Preliminary study using inactive Re instead of TcTanase, Masakazu*; Fujisaki, Saburo*; Ota, Akio*; Shiina, Takayuki*; Yamabayashi, Hisamichi*; Takeuchi, Nobuhiro*; Tsuchiya, Kunihiko; Kimura, Akihiro; Suzuki, Yoshitaka; Ishida, Takuya; et al.
Radioisotopes, 65(5), p.237 - 245, 2016/05
no abstracts in English
Mo/
Tc production by neutron activation methodIshida, Takuya; Shiina, Takayuki*; Ota, Akio*; Kimura, Akihiro; Nishikata, Kaori; Shibata, Akira; Tanase, Masakazu*; Kobayashi, Masaaki*; Sano, Tadafumi*; Fujihara, Yasuyuki*; et al.
JAEA-Technology 2015-030, 42 Pages, 2015/11
JAEA-Technology-2015-030.pdf:4.82MB
The research and development (R&D) on the production of Mo/Tc by neutron activation method ((n, 
) method) using JMTR has been carried out in the Neutron Irradiation and Testing Reactor Center. The specific radioactivity of Mo by (n, ) method is extremely low compared with that by fission method ((n,f) method), and as a result, the radioactive concentration of the obtained Tc solution is also lowered. To solve the problem, we propose the solvent extraction with methyl ethyl ketone (MEK) for recovery of Tc from Mo produced by (n, ) method. We have developed the Mo/Tc separation/extraction/concentration devices and have carried out the performance tests for recovery of Tc from Mo produced by (n, ) method. In this paper, in order to establish an experimental system for Mo/Tc production, the R&D results of the system are summarized on the improvement of the devices for high-recovery rate of Tc, on the dissolution of the pellets, which is the high-density molybdenum trioxide (MoO
) pellets irradiated in Kyoto University Research Reactor (KUR), on the production of Tc, and on the inspection of the recovered Tc solutions.
Mo/Tc production by (n,) methodNishikata, Kaori; Kimura, Akihiro; Ishida, Takuya; Shiina, Takayuki*; Ota, Akio*; Tanase, Masakazu*; Tsuchiya, Kunihiko
JAEA-Technology 2014-034, 34 Pages, 2014/10
JAEA-Technology-2014-034.pdf:3.26MB
As a part of utilization expansion after the Japan Material Testing Reactor (JMTR) re-start, research and development (R&D) on the production of medical radioisotope Mo/Tc by (n, ) method using JMTR has been carried out in the Neutron Irradiation and Testing Reactor Center of the Japan Atomic Energy Agency. Mo is usually produced by fission method. On the other hand, Mo/Tc production by the (n, ) method has advantages for radioactive waste, cost reduction and non-proliferation. However, the specific radioactivity per unit volume by the (n, ) method is low compared with the fission method, and that is the weak point of the (n, ) method. This report summarizes the investigation of raw materials, the fabrication tests of high-density MoO pellets by the plasma sintering method for increasing of 
Mo contents and the characterization of sintered high-density MoO pellets.
Shiina, Takuya*; Watanabe, Ritsuko; Suzuki, Masao*; Yokoya, Akinari
Journal of Radiation Research, 55(Suppl.1), p.i15 - i16, 2014/03
Shiina, Takuya; Watanabe, Ritsuko; Shiraishi, Iyo; Suzuki, Masao*; Sugaya, Yuki; Fujii, Kentaro; Yokoya, Akinari
Radiation and Environmental Biophysics, 52(1), p.99 - 112, 2013/03
Times Cited Count：23 Percentile：63.72(Biology)Toyokawa, Takuya; Usami, Koji; Shiina, Hidenori; Onozawa, Atsushi
Proceedings of 49th Conference on Hot Laboratories and Remote Handling (HOTLAB 2012) (Internet), 6 Pages, 2012/09
Shiraishi, Iyo; Shiina, Takuya; Sugaya, Yuki; Shikazono, Naoya; Yokoya, Akinari
no journal, ,
no abstracts in English
Tc from irradiated High-density MoO Pellets SolutionShibata, Akira; Ishida, Takuya; Shiina, Takayuki*; Kobayashi, Masaaki*; Tanase, Masakazu*; Kato, Yoshiaki; Kimura, Akihiro; Ota, Akio*; Yamamoto, Asaki*; Morikawa, Yasumasa*; et al.
no journal, ,
Tc, a daughter nuclide of Mo, is commonly used as a radiopharmaceutical. In case of Japan, all of Mo are imported from foreign countries. R&D for domestic production of Mo by the (n, ) method has been being performed in JMTR from viewpoints of nuclear proliferation resistance and waste management. In this study, experiments of Mo/Tc production were performed to enhance recovery yields of Tc. High-density MoO pellets were irradiated in the Kyoto University Reactor (KUR). Solvent extraction method with MEK was used to extract Tc from Mo/Tc solution and the maximum recovery yields as high as 80% was achieved. Quality tests were performed, and impurities in Tc solution were evaluated and were efficiently low. It is concluded that Tc solution produced by this method is suitable for a raw material of radiopharmaceutical.
Mo/Tc production using irradiated MoO pelletsNishikata, Kaori; Kimura, Akihiro; Shiina, Takayuki*; Yamamoto, Asaki*; Ishida, Takuya; Ota, Akio*; Tanase, Masakazu*; Takeuchi, Nobuhiro*; Morikawa, Yasumasa*; Kobayashi, Masaaki*; et al.
no journal, ,
JP, 2011-173260 Patent publication (In Japanese)
no abstracts in English
Shiina, Takuya; Shiraishi, Iyo; Sugaya, Yuki; Watanabe, Ritsuko; Suzuki, Masao*; Yokoya, Akinari
no journal, ,
no abstracts in English
Sugaya, Yuki; Shiina, Takuya; Shiraishi, Iyo; Fujii, Kentaro; Yokoya, Akinari
no journal, ,
no abstracts in English
Shiina, Akira; Yamashita, Takuya; Watanabe, Toshio; Imai, Yoshiyuki*; Ono, Koichi*
no journal, ,
no abstracts in English
Shiina, Takuya; Sugaya, Yuki; Shiraishi, Iyo; Watanabe, Ritsuko; Yokoya, Akinari
no journal, ,
Many studies using synthetic AP clusters reported that AP clusters retard base excision repair processes. Sutherland et al. (2002) showed that AP clusters are induced efficiently in human cells by low LET X-irradiation with the similar yields with those for the pyrimidine or purine base lesion clusters. There, however, has been very little knowledge of AP sites and AP clusters induced by high LET radiation. In order to clarify the relation between track structure of C ions or X-rays and the induction processes of an AP or AP clusters, we measure the yield of AP sites visualized by the treatment of irradiated pUC18 plasmid DNA with the AP endoclease (Nfo), which converts an AP site to detectable single strand break. Several scavenging capacities of the samples are tested to estimate the effect of indirect action of diffusible OH radicals. These experimental data will be discussed with theoretical radiation track structure in the respect of repair susceptibility of the AP cluster.
Sugaya, Yuki; Shiraishi, Iyo; Shiina, Takuya; Fujii, Kentaro; Yokoya, Akinari
no journal, ,
no abstracts in English
Tc from Mo produced by (n,) methodTanase, Masakazu*; Shiina, Takayuki*; Ota, Akio*; Fujisaki, Saburo*; Kawauchi, Yukimasa*; Kimura, Akihiro; Nishikata, Kaori; Yonekawa, Minoru; Ishida, Takuya; Kato, Yoshiaki; et al.
no journal, ,
Preliminary studies for obtaining Tc from, (n,)Mo produced in JMTR has been carried out, as a part of the industrial use expansion after JMTR will re-start. In order to obtain high specific-volume of Tc, a method was proposed for extracting Tc with MEK, followed by purification and concentration with acidic and basic alumina. In this study, preliminary tests, aiming construction of production system, were carried out using Re instead of Tc because Re and Tc are homologous elements. The average recovery yield of Re was very high to be 98%. Based on the result, an apparatus for Tc production was assembled.
Shiina, Takuya; Sugaya, Yuki; Shiraishi, Iyo; Watanabe, Ritsuko; Suzuki, Masao*; Yokoya, Akinari
no journal, ,
no abstracts in English
Sugaya, Yuki; Shiina, Takuya; Shiraishi, Iyo; Fujii, Kentaro; Yokoya, Akinari
no journal, ,
no abstracts in English
Watanabe, Ritsuko; Shiina, Takuya*; Yokoya, Akinari
no journal, ,
This study aims to examine and develop the production models of base damage in order to obtain the detail of the spectrum of initial DNA damage consisting of strand breaks and base lesions. Monte Carlo track structure code for ions TRACION and the DBREAK code system were used for the simulation for irradiation by photons and ions. The number and configuration of lesions on the DNA segment within a few tens base pairs length were estimated. In the presentation, the tested results will be compared with some available experimental data and examine. The detail of the positional distribution of damages which may be related to the inhibition of repair processing will be presented. In addition, the obtained DNA damage spectrum will be discussed related to not only LET but also microdosimetric quantities as specific energy or linear energy.
Sugaya, Yuki; Shiina, Takuya; Shiraishi, Iyo; Fujii, Kentaro; Yokoya, Akinari
no journal, ,
In this study, we aim to reveal the role of direct ionization at the energy region of oxygen K-edge in the selective DNA damage. We measure the yields of single strand breaks (SSBs), base lesions, and AP sites produced in thin film of pUC18 plasmid DNA by irradiation of several soft X-rays which excite a1s electron to anti-bonding energy states or a vacuum level. The yields of base lesions and AP sites are determined by post-irradiation-treatment of the DNA with enzymatic probes, which excise (Nth and Fpg for pyrimidine and purine base lesion, respectively, and Nfo for AP site) and convert the lesions into detectable SSBs. The obtained data will be compared with our previous data obtained by soft X-ray irradiation around carbon and nitrogen K-edge region.
Shiraishi, Iyo; Shiina, Takuya; Sugaya, Yuki; Shikazono, Naoya; Yokoya, Akinari
no journal, ,
