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ABSTRACT: Polymeric micelles loaded with cis-diamminedichloroplatinum(II), CDDP, (cisplatin micelles) enable higher accumulation in solid tumors and lower toxicities compared with CDDP alone. The combined use of cisplatin micelles with radiation is expected to enhance therapeutic effects and reduce side effects. The kinetics of cisplatin micelle uptake, however, have not been fully understood. Particle Induced X-Ray Emission has been employed in this study to measure the time transients of platinum in Chinese Hamster ovary cells. The results show that the platinum content of cells treated with cisplatin micelles increased more slowly than with CDDP alone, suggesting that cellular uptake could be controlled using micelles. The CDDP released from micelles was predominantly incorporated into the cells by diffusion. The uptake characteristics were further analyzed using micelles with different collapse rates. The results and techniques used in this study will be useful for designing an optimum treatment plan combining platinum-containing polymeric micelles and radiation in clinical applications.
Journal of Radiation Research 12/2010; 52(2):193-8. · 1.68 Impact Factor
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Yasuhiko Kobayashi,
Tomoo Funayama,
Nobuyuki Hamada,
Tetsuya Sakashita,
Teruaki Konishi, Hitoshi Imaseki,
Keisuke Yasuda,
Masanori Hatashita,
Keiichi Takagi,
Satoshi Hatori,
Keiji Suzuki,
Motohiro Yamauchi,
Shunichi Yamashita,
Masanori Tomita,
Munetoshi Maeda,
Katsumi Kobayashi,
Noriko Usami,
Lijun Wu
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ABSTRACT: In order to study the radiobiological effects of low dose radiation, microbeam irradiation facilities have been developed in the world. This type of facilities now becomes an essential tool for studying bystander effects and relating signaling phenomena in cells or tissues. This review introduces you available microbeam facilities in Japan and in China, to promote radiobiology using microbeam probe and to encourage collaborative research between radiobiologists interested in using microbeam in Japan and in China.
Journal of Radiation Research 03/2009; 50 Suppl A:A29-47. · 1.68 Impact Factor
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ABSTRACT: Intestinal permeability has been suggested to be closely linked with the etiology or activity of Crohn's disease. However, current methods for measurement of intestinal permeability are too laborious for routine examination, as they require urine collection and/or use of radioisotopes. The present study was performed to develop a more convenient and safer method for assessing intestinal permeability using blood samples rather than urine. Rats with indomethacin-induced enteritis were orally administered Rb, Mn, and Zn as tracers. Intestinal permeability was determined by assaying the levels of Rb, Mn, and Zn in blood samples by particle-induced X-ray emission (PIXE). The distributions of Rb, Mn, and Zn in the small intestine after administration were analyzed by micro-PIXE. The conventional PIXE analysis showed that the levels of Rb and Zn in the blood in the enteritis group were correlated with the grade of enteritis. The micro-PIXE analysis showed that Rb, Mn, and Zn were translocated into the wall of the proximal small intestine 5 min after administration, and this effect was more conspicuous in the enteritis group than in controls. Analysis of blood or small intestine tissue samples using the PIXE allows determination of both intestinal permeability and the route of permeation.
Biological Trace Element Research 05/2004; 98(1):27-43. · 1.92 Impact Factor
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ABSTRACT: In March 1999, a HVEE Tandetron was installed in the Electrostatic Accelerator Building of National Institute of Radiological Sciences (NIRS) for particle induced X-ray emission (PIXE) analysis. The specifications of the Tandetron accelerator system operating at NIRS are as follows: the accelerating voltage is 0.4–1.7 MV, and the maximum beam current is 500 nA at 3.4 MeV. The accelerator facility incorporates three beam lines for conventional, in-air and microbeam PIXE analysis.The scanning microbeam PIXE analysis line is based around an Oxford Microbeams OM2000 nuclear microscope end stage. This system provides the ability of multi-elemental mapping over sample areas up to 2×2 mm area with spatial resolutions routinely at 1×1 μm. The scheduled operation of this facility started in April 2000 and is controlled by the Division of Technical Service and Development. The result of beam resolution tests carried out in 2001 are as follows: for scanning transmission ion microscopy, the estimated beam size is 100×200 nm, measured using a 2.6 MeV proton beam scanned over a 12.7 μm repeat distance copper grid. For PIXE operation at 50 pA beam current the estimated best spot size is 0.4×0.6 μm. The microbeam facility is being used for research into the elemental distribution of small biological samples such as biological cells and tissue.
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms - NUCL INSTRUM METH PHYS RES B. 01/2003; 210:42-47.
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ABSTRACT: We have developed the interlock and beam exposure control system of NIRS Neutron exposure Accelerator System for Biological Effects Experiments (NASBEE) The TANDETRON 2MV HC+5812, by HVEE, is adopted as the main body of system. The facility comprises both accelerator - based neutron and RI - based gamma exposure systems, where radiation control area and biological SPF control area are intermingled. The system has to control any access in view of both aspects of interlock. The major interlock in neutron exposure area is realized first by a FC that stops the beam before the accelerator tube, and then terminal voltage control. Radiation from neutron target must be shielded also before accessing to the area. The development system comprises three PLC's and PC. Three PLC's control interlock, exposure devices, and area-access, respectively, system makes exposure control and measurements easy. Further improvement for user-friendliness is expected in future.
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ABSTRACT: Synchrotron radiation X-ray fluorescence (SR-XRF) using high energy incident X-rays was combined with micro-PIXE to analyze the renal distribution of Rb and essential elements in immature rats. The Rb concentrations in the kidneys of newborn (1 week old) and young (3 weeks old) rats were 4.19 ± 0.71 and 4.13 ± 0.30 μg/g, respectively, similar to those of adult rats. Rubidium as well as Zn was detected more in the cortex than the medulla, while Fe was concentrated in the outermost areas of the medulla of newborn rats. The renal structures of young rats achieved adult zonation into the cortex, the outer medulla and the inner medulla. Rubidium was high in the outer stripe of the outer medulla. Further analysis at higher resolution revealed Rb in the proximal tubules in the innermost part of the cortex. These results indicated that Rb was distributed downstream of the proximal tubules. This profile was similar to that of potassium, an Rb congener.
19:39-45.
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ABSTRACT: We originally developed a preparation method for samples of automobile engine lubricating oil (liquid sample) specifically designed for in-air particle induced X-ray emission (PIXE) analysis with Helium ions. In the developed preparation method, target samples were fixed by making the oil sample sandwiches with 1% collodion solution based ethanol. With this analytical method, elements such as Al, Si, P, S, Cl, Ca and Zn can be detected from the oil samples, while Si, P, S, Ca and Zn were the elemental components of the oil additives.
18:47-53.
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ABSTRACT: For muti-elemental analysis, various standards are used to quantify the elements consists of environmental and biological samples. In this paper two different configuration standards, pressed powders and thin section standards, were assessed for their purpose as standards by conventional and micro-PIXE analysis. Homogeneity of manganese, iron, zinc (Zn), copper and yttrium added to pressed powder standard materials were validated and the relative standard deviation (RSD) of the X-ray intensity of the standards was <10% within the range, 62.5â250 µg/g. We established linear relationships between the metal concentration and the specific X-ray intensity of standards containing up to 250 µg/g of these metals. A homogenous distribution of Zn added to thin section standard materials was also confirmed by 10-µm-step scanning of the standard within the range, 50â250 µg/g (RSD ~ 10%). The calibration line between the X-ray intensity obtained from a 10-µm2 area and the metal concentration was acceptable
20:21-28.
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52:193-198.
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Hiroshi Yamaguchi,
Yukio Sato, Hitoshi Imaseki,
Nakahiro Yasuda,
Tsuyoshi Hamano,
Yoshiya Furusawa,
Masao Suzuki,
Takehiro Ishikawa,
Teiji Mori,
Kenichi Matsumoto,
Teruaki Konishi,
Masae Yukawa,
Fuminori Soga
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ABSTRACT: Selective irradiation by an ionizing particle of a targeted cell organelle may disclose such mechanisms as signal transactions among cell organelles and cell-to-cell communication in the processes toward an endpoint observed. Bystander effect, existence of which has been clearly evidenced by application of the particle microbeam to biological experiments suggests potential deviation from the conventional risk estimation at low particle fluence rates, such as in an environment of space radiation in the International Space Station. To promote these studies, we started the construction of a microbeam facility (named single-particle irradiation system to cell [SPICE]) by using our HVEE Tandem accelerator (3.4 MeV proton and 5.1 MeV 4He2+). For our primary goal, irradiation of a cell organelle with a single particle with a position resolution of 2 [mu]m in a reasonable irradiation time, special features are considered. Usage of a triplet Q magnet for focusing the beam to micrometer levels is an outstandin
1258:281-285.
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Journal of Radiation Research. 52(2):193-198.
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ABSTRACT: We originally developed a preparation method for samples of automobile engine lubricating oil (liquid sample) specifically designed for in-air particle induced X-ray emission (PIXE) analysis with Helium ions. In the developed preparation method, target samples were fixed by making the oil sample sandwiches with 1% collodion solution based ethanol. With this analytical method, elements such as Al, Si, P, S, Cl, Ca and Zn can be detected from the oil samples, while Si, P, S, Ca and Zn were the elemental components of the oil additives.
International Journal of PIXE. 18(1&2):47-53.
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Hiroshi Yamaguchi,
Yukio Sato, Hitoshi Imaseki,
Nakahiro Yasuda,
Tsuyoshi Hamano,
Yoshiya Furusawa,
Masao Suzuki,
Takehiro Ishikawa,
Teiji Mori,
Kenichi Matsumoto,
Teruaki Konishi,
Masae Yukawa,
Fuminori Soga
[show abstract]
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ABSTRACT: Selective irradiation by an ionizing particle of a targeted cell organelle may disclose such mechanisms as signal transactions among cell organelles and cell-to-cell communication in the processes toward an endpoint observed. Bystander effect, existence of which has been clearly evidenced by application of the particle microbeam to biological experiments suggests potential deviation from the conventional risk estimation at low particle fluence rates, such as in an environment of space radiation in the International Space Station. To promote these studies, we started the construction of a microbeam facility (named single-particle irradiation system to cell [SPICE]) by using our HVEE Tandem accelerator (3.4 MeV proton and 5.1 MeV 4He2+). For our primary goal, "irradiation of a cell organelle with a single particle with a position resolution of 2 [mu]m in a reasonable irradiation time," special features are considered. Usage of a triplet Q magnet for focusing the beam to micrometer levels is an outstanding feature compared to facilities of other institutes. Other features are almost similar to those of other institutes. Those are precise position control of a cell dish holder, design of the cell dish, data acquisition of the microscopic image of a cell organelle (cell nucleus), data processing, reliable particle detection, software and hardware to integrate all these related data, and a system to control and irradiate a targeted spot with an exactly determined number of particles.
International Congress Series. 1258:281-285.
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Masao Suzuki,
Yoshiya Furusawa,
Tomoo Funayama,
Noriko Usami,
Kana Fukamoto,
Yuichiro Yokota,
Nobuyuki Hamada,
Teruaki Konishi,
Chizuru Tsuruoka,
Nakahiro Yasuda,
Takahiro Ishikawa,
Cuihua Liu,
Hiroyuki Iso,
Masakazu Oikawa, Hitoshi Imaseki,
Katsumi Kobayashi,
Yasuhiko Kobayashi
Journal of Radiation Research. 50:A92.
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ABSTRACT: At the National Institute of Radiological Sciences (NIRS), we constructed a microbeam system in 2003, the single particle irradiation to cell, SPICE. From the beginning of 2005, we redesigned it to improve the stability of the optical alignment of the system, and obtained an reduction of the beam size proportional to the vertical dimension of the object slits. As a result, SPICE is now capable of producing a beam size of approximately 10 μm diameter, and the particle numbers controllable to an intensity as low as single particles per second, and therefore a single particle irradiation facility has been successfully implemented. Moreover, these conditions can be easily reproduced with a employing a routine procedure. We describe in detail the modifications of the beam line and results, demonstrating the improvements. In addition, results from our first biological experiments are shown.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms.
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ABSTRACT: Microbeam scanning-PIXE (micro-PIXE) analysis is a useful method for obtaining information of multi-elemental distribution in samples by two-dimensional images of sample surfaces such as mammalian cells, tissues, and other environmental monitoring species. In addition to elemental distribution information, quantitative analysis is in demand for further investigations of environmental and biomedical studies concerning heavy metals accumulated in terms of cells and sub-cellular organelles. To make quantitative analysis possible, a real-time beam monitoring system that gives a precise number of ions, and an output independent from a sample that enables one to keep a beam resolution of micrometer size is required. In this paper, we report on the development of beam current monitoring. The beam current was monitored using a ceramic channel electron multiplier (CEM) to detect secondary electrons induced from a 50 nm thick carbon film (10 μg/cm2). This carbon film was attached to a sample holder, which was set at the targeted sample position. The output value of the CEM was proportional to the Faraday cup installed just after the sample position. The beam resolution was measured using off-axis STIM by scanning a copper grid, and was estimated at 1.79 and 1.72 μm for the horizontal and vertical directions, respectively, sufficient for routine micro-PIXE analysis.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms.
