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Volume 32, Issue 3
Displaying 1-5 of 5 articles from this issue
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ALVARO A. MEJIA, TAKASHI NAKAMURA, MASATOSHI ITOH, JUN HATAZAWA, KIICH ...1991 Volume 32 Issue 3 Pages 243-261
Published: September 15, 1991
Released on J-STAGE: May 31, 2006
JOURNAL FREE ACCESSAbsorbed doses were estimated after intravenous administration of 18f-labeled radiopharmaceuticals in Positron Emission Tomography (PET) studies. These radiopharmaceuticals, [18f]-2-Fluoro-2-Deoxy-D-Glucose (FDG), 6-[189F]Fluoro-L-Dopa (FDOPA) and 18f-5-Fluorodeoxyuridine (FdUR), are used in clinical research at the Cyclotron and Radioisotope Center of Tohoku University. Radiopharmaceutical biokinetic values were measured in humans or extrapolated from animal experiments. Selective organ uptake and rapid clearance of activity from the blood were observed. High activity in the bladder contents of humans was found. Calculations were made by the MIRD method, modified to account for the differences in physique and organ mass between the Caucasian Reference Man and the Japanese one. The bladder wall receives the highest dose (more than 1.23 × 10-1 mGy/MBq) when any of these compounds are administered. Other organs receiving high doses are the heart, brain and kidneys from FDG; the kidneys and pancreas from FDOPA, and the kidneys and small intestine from FdUR. These organs received absorbed doses of more than 2.7 × 10-2 mGy/MBq. Effective dose equivalents of 2.4 × 10-2, 2.6 × 10-2 and 3.3 × 10-2 mSv/MBq were estimated in the intravenous administration of 18F-FDG, 18f-FDOPA and 18f-FdUR, respectively.View full abstractDownload PDF (661K) -
SENTARO TAKAHASHI, YOSHIHISA KUBOTA, HIROSHI SATO1991 Volume 32 Issue 3 Pages 262-266
Published: September 15, 1991
Released on J-STAGE: May 31, 2006
JOURNAL FREE ACCESSThe effect of external γ-irradiation on 59Fe release from alveolar macrophages (AMs) that had ingested 59Fe-iron hydroxide colloid was determined in C3H mice and Wistar rats with an in vitro assay system. The release of ''9Fe from AM was increased by irradiation in mice but not in rats. A significant increase in 59Fe release was seen in mouse AM cultured for 72 hrs after irradiation at a dose of more than 25 Gy; but, graded doses of γ-irradiation up to 100 Gy had no effect on 59Fe release from rat AMs. This difference between mice and rats may be attributable to the magnitude of death of or damage to AM because the survival of AMs assessed by vital staining with crystal violet decreased much more in mice than in rats.View full abstractDownload PDF (223K) -
Tritium Precipitation in European Cities and in Osaka, Japan Owing to the Chernobyl Nuclear AccidentTAEKO KOGA, HIROSHIGE MORISHIMA, TAKEO NIWA, HIROSHI KAWAI1991 Volume 32 Issue 3 Pages 267-276
Published: September 15, 1991
Released on J-STAGE: May 31, 2006
JOURNAL FREE ACCESSTritium precipitations in European cities and in Osaka, Japan were analyzed before and after the Chernobyl nuclear plant accident by the time series analysis code Census 11X11 developed by US Department of Commerce Bureau of the Census. Results of this analysis showed no significant tritium precipitation was produced by the accident although marked amounts of other radioactive nuclides were detected in Europe and Japan immediately after the accident.View full abstractDownload PDF (294K) -
NOBUKO MORI, RYOSUKE NISHIKAWA, MASAAKI OKUMOTO, KIYOSHI NISHIKAWA, SY ...1991 Volume 32 Issue 3 Pages 277-285
Published: September 15, 1991
Released on J-STAGE: May 31, 2006
JOURNAL FREE ACCESSThe susceptibility of thymocytes from STS/A to radiation-induced cell death was compared with that of thymocytes from BALB/cHeA. After in vitro exposure to 12 Gy X-ray, thymocytes were incubated at 37°C for 8 h and then cell mortality was assessed by 0.02% erythrosin B exclusion. Cell death took place from 2 h in the incubation period, reaching a maximum at 6 h for both strains. The dose-effect on cell death at 4 h of incubation was examined after 1-24 Gy of X-irradiation. An increase in cell death was detectable even at 1 Gy in both strains. The number of dead cells in BALB/cHeA gradually increased with doses of more than 1 Gy, finally to a maximum (approximately 60%) in the dose range of 8-12 Gy, whereas the maximum cell death in STS/A was approximately 40%. The difference between the strains at maximum cell death was significant (P<0.005). The difference in the radiosensitivity of thymocytes between the two strains could not be attributed to a difference in the composition of their subpopulations because flow cytometric analysis based on the expression of CD4 and CD8 showed no intrinsic difference in the thymocyte subpopulations of BALB/cHeA and STS/A.View full abstractDownload PDF (390K) -
OSAMU YAMAMOTO, TAEKO JO, MASANORI SUGIYAMA, TAKUJI ITOH1991 Volume 32 Issue 3 Pages 286-295
Published: September 15, 1991
Released on J-STAGE: May 31, 2006
JOURNAL FREE ACCESSRadioresistant E. coli TG1 harboring pUC 18 plasmid which was Ampicillin-resistant was exposed to 60Co gamma-rays or 3H beta-rays in saline to determine whether the relative biological effectiveness of 3H beta-rays is higher than one. After exposure to 60CO gamma-rays at a dose rate of 0.465 Gy/min, the D0 by colony formation was 145 Gy in the presence of Ampicillin in or absence from the agar medium; whereas, the D0 was calculated as 118 Gy with and without Ampicillin after exposure to 3H beta-rays at a dose rate of 0.431 Gy/min. The relative biological effectiveness established for 3H beta-rays to 60Co gamma-rays was 1.23. The reason for the higher effectiveness of 3H beta-rays as compared to the reference 60Co gamma-rays is discussed in terms of nascent 0 production.View full abstractDownload PDF (375K)
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