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Tetsuya SAKASHITA | Cited by 1,590 | of Japan Atomic Energy Agency, Muramatsu (JAEA) | Read 366 publications | Contact Tetsuya SAKASHITA
- Introduction
- Materials and Methods
- Results and Discussion
- Acknowledgements
- Funding
Animals are exposed to radiation from natural and artificial sources, cosmic rays, and nuclear accidents. Radiation may affect essential functions and behaviors such as locomotion, feeding, learning and memory, and it is therefore necessary to understand the effects of radiation exposure on these aspects. Locomotory behavior is vital for securing f...
Strains and culture
C. elegans strain wild-type N2 and Escherichia coli strain HB101 were obtained from the Caenorhabditis Genetics Center. C. elegans hermaphrodites were grown at 20°C on a non-treated petri plate (IWAKI 60 mm/non-treated dish, AGC Techno Glass Co., Ltd, Shizuoka, Japan) containing 10 ml of nematode growth medium (NGM) spread with E. coli as food. Well-fed adult animals (~3 days after hatching) were used in all experiments.
Sample preparation immediately before irradiation
Before irradiation, an individual C. elegans was collected from the culture plate using a platina picker (WormStuff Worm Pick, Genesee Scientific Corporation, San Diego, CA, USA) and washed twice in drops of S basal buffer solution on a non-treated petri plate (Fig. 1A). Free motion of C. elegans during irradiation was inhibited using a PDMS microfluidic chip (Fig. 1B). The surface of the chip included five straight microfluidic channels (depth, 40 μm; width, 40, 50, 60, 70 or 80 μm...
Region-specific microbeam or whole-body broad-beam irradiation with high-linear energy transfer carbon ions
We investigated the effects of region-specific microbeam irradiation using carbon ion (12C5+) particles accelerated by an azimuthally varying field cyclotron installed at the Takasaki Ion Accelerators for Advanced Radiation Application (TIARA) facility of QST-Takasaki. We delivered region-specific microbeam irradiation using a collimating microbeam system (Fig. 2). The microfluidic chip enclosing an individual C. elegans placed on a custom-made aluminum frame (Fig. 1C) was located on the...
Establishment of method for region-specific irradiation of an animal without anesthesia
To examine the immediate effects of region-specific irradiation on locomotion in C. elegans, we developed a method that inhibited free motion only during irradiation, without the need for anesthesia. To achieve this, we used a behavior chip (PDMS microfluidic chip) to immobilize an animal, by placing it in a straight, close-fitting microfluidic channel in a chip (Fig. 1D). This allowed accurate targeting of region-specific irradiation to a limited area of the body, and observation of locomoti...
Region-specific irradiation had no significant effect on motility
We determined whether the observed radiation-induced reduction in motility was caused by irradiation to a specific region, e.g. the nerve ring responsible for information processing, or by irradiation of the muscle cells themselves. As a control experiment, we examined the effects of whole-body irradiation on C. elegans restrained in a microfluidic chip, and found that motility was significantly decreased immediately after whole-body irradiation with 500 Gy of carbon-ion broad beam (Fig. 4A)....
The authors thank Dr Shawn R. Lockery for kindly providing microfluidic chips and detailed information; Dr Katsuyoshi Takano for technical advice on treatment of microfluidic chips; and the Caenorhabditis Genetic Center at the University of Minnesota for providing strains of C. elegans and E. coli. We thank Dr Yasuko Mutou-Yoshihara, Dr Hiroko Iked...
This study was supported in part by MEXT KAKENHI Grant Number JP20115010 to M.S. and JSPS KAKENHI Grant Numbers JP24620013, JP15K11921, JP15H03950 to M.S.
- Michiyo Suzuki, Yuya Hattori, Tetsuya Sakashita, Yuichiro Yokota, Yasuhiko Kobayashi, Tomoo Funayama
- 2017
Jul 30, 2021 · In an interview with the Mainichi Shimbun, Tetsuya Sakashita, who is well-versed in public sector systems, and is an executive managing director at JIPDEC, a general incorporated foundation...
Abstract. The effects of heavy ion microbeams on muscle fibers isolated from mouse skeletal muscles were examined by electron microscopy. The plasma membranes of heavy ion beam-irradiated areas of muscle fibers showed irregular protrusions and invaginations.
- Mizuki Hino, Seiichi Wada, Yuki Tajika, Yoshihiro Morimura, Nobuyuki Hamada, Nobuyuki Hamada, Tomoo ...
- 2007
Sep 10, 2021 · Suzuki M., Sakashita T., Hattori Y., Yokota Y., Kobayashi Y., Funayama T. Development of ultra-thin chips for immobilization of Caenorhabditis elegans in microfluidic channels during irradiation and selection of buffer solution to prevent dehydration.
- Akira Yamasaki, Michiyo Suzuki, Tomoo Funayama, Takahito Moriwaki, Takahito Moriwaki, Tetsuya Sakash...
- 10.3390/ijms22189810
- 2021
- Int J Mol Sci. 2021 Sep; 22(18): 9810.
Tetsuya Sakashita was born in Gifu, Japan, on February 13, 1968. He received the Ph.D. degree in nuclear engineering from Nagoya University, Nagoya, Japan, in 1997. He was a Research Fellow with the Japan Science and Technology Agency from 1995 to 1998 and with the National Institute of Radiological Sciences from 1998 to 2003.
Sep 7, 2017 · Miyazawa Y, Sakashita T, Funayama T, et al.. Effects of locally targeted heavy-ion and laser microbeam on root hydrotropism in Arabidopsis thaliana. J Radiat Res 2008; 49:373–9. [Google Scholar]
