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Volume 31 (1990)
- Issue 4 Pages 311-
- Issue 3 Pages 235-
- Issue 2 Pages 147-
- Issue 1 Pages 97-
Volume 31, Issue 4
Displaying 1-9 of 9 articles from this issue
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YOSHIKAZU INOUE, TETSUO IWAKURA1990 Volume 31 Issue 4 Pages 311-323
Published: December 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSPolished rice samples harvested in 1985 were collected from 25 prefectures throughout Japan. Concentrations of both tissue free water tritium (TFWT) and organically bound tritium (OBT) were determined.
Nearly uniform distribution of the TFWT and OBT concentrations was observed in Japan, taking into account a relatively large counting error. The average values for all Japanese polished rice were 2.69 ±0.74 Bq/L for the TFWT concentration, 2.01 ±0.78 Bq/L for the OBT concentration and 0.83 ±0.32 for the specific activity ratio.
The TFWT concentration was within the range of tritium concentration of the land water reported by other researchers. The specific activity ratio below unity also confirmed by analyses of the 4 Chinese polished rice samples suggests that OBT in the rice is not equilibrated with TFWT or HTO in the environment because of isotope discrimination.View full abstractDownload PDF (493K) -
YOICHI OGHISO, YUTAKA YAMADA, YOSHIMI SHIBATA1990 Volume 31 Issue 4 Pages 324-332
Published: December 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSM-CFC Radiosensitivity Survival Antigen Expression Heterogeneity MouseView full abstractDownload PDF (326K) -
TAKEO YAMAGUCHI, CHIDORI MURAISO, IKUKO FURUNO-FUKUSHI, ATSUSHI TSUBOI1990 Volume 31 Issue 4 Pages 333-339
Published: December 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSOne of the critical factors for dosimetry of beta-rays from tritiated water is the water content within the cell.
We estimated the cellular water concentration in cultured mammalian cells by measuring accurately the fraction of the extracellular water in the cell sample with [14C] inulin.
The net water content (ml·g-1) after correcting for the extra-cellular water fraction was 0.858 for HeLa (human), 0.833 for JTC12P3 (monkey), 0.829 for NRK (rat), 0.843 for C3H10T1/2 (mouse) and 0.846 for L5178Y (mouse) cells. The mean water content (± S.E.M.) in these 5 lines of cultured mammalian cells was 0.842 ± 0.005.View full abstractDownload PDF (261K) -
SURINDER P. SINGH, DAVID COHEN, NICK DYTLEWSKI, JANE HOULDSWORTH, MART ...1990 Volume 31 Issue 4 Pages 340-353
Published: December 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSWe describe here the use of the Van de Graaff accelerator as a source of high energy neutrons for biological irradiation. Single-stranded bacteriophage M13 DNA was chosen as the system to determine the relative biological effectiveness of monoenergetic neutrons. A Standard Neutron Irradiation Facility (SNIF) was established using a 3 MV Van de Graaff accelerator. The 2D (d, n)3He nuclear reaction was used to produce neutron fluxes of 3 × 108 cm-2 sec-1 yielding dose rates as high as 50 Gy h-1. A detailed description of the neutron source, neutron fluence measurement, dose calculation and calibration are included. Exposure of single-stranded bacteriophage M13 DNA to 90 Gy of neutrons reduced survival to 0.18% of the unirradiated value. 500 Gy of γ-rays were required for the same level of killing, and RBE was estimated at 6 based on Do values. Determination of the extent of DNA damage after exposure to cleavage using gel electrophoresis, gave RBE values of 6-8 which was very similar to that observed for bacteriophage survival. The facility described here provides a reproducible source of high energy monoenergetic neutrons and dose levels suitable for experiments designed to measure DNA damage and effects on DNA synthesis.View full abstractDownload PDF (615K) -
M. PRAKASH HANDE, P. UMA DEVI, G. C. JAGETIA1990 Volume 31 Issue 4 Pages 354-360
Published: December 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSPregnant Swiss albino mice were exposed to a single dose of 9 mGy or 50 mGy of 70 kVp X-rays on day 3.5 (preimplantation), 6.5 (early organogenesis) or 11.5 (late organogenesis) of gestation. The offspring were observed for any radiation induced changes in litter size at birth and sex ratio at 4 wks of age, and postnatal mortality and growth retardation up to 6 wks of age. Irradiation at the early organogenesis stage produced an increase in the postnatal death, statistically significant in the 50 mGy group. A significant increase in the number of retarded offspring and decrease in body weight were observed in the groups exposed at the early and late organogenesis periods. The results indicate that a single exposure to low energy low dose X-rays can be harmful to the growing embryos and the type and extent of the injury will depend on the stage of development as well as the dose of radiation.View full abstractDownload PDF (275K) -
NAOKI KUNUGITA, SEITARO DOHI, HISAO YAMAMOTO, TOSHIYUKI NORIMURA, TAKE ...1990 Volume 31 Issue 4 Pages 361-374
Published: December 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSThis study was undertaken to determine whether or not the administration of diuretics and excess water after tritium exposure would have any positive reducing effect not only on the retention of tritium but also on the radiation damage of hematopoietic tissue in mice. When mice were treated with diuretics and excess water for a few days after injection of tritiated water (HTO), radioactivity within the body fluid and tissues was reduced, and the number of CFU-s, clonability of splenic T cells and proliferative activity assayed by Con-A blastogenesis were increased in comparison with those in the controls. When the mice were injected with a large dose of HTO (811 MBq/mouse) to assay survival, no mice treated with diuretic and excess water died 80 days after injection, while 80% of the controls died during the first month. The final committed dose in the mice treated early with diuretics was calculated to be 60% of that in the controls. These results suggest that treatment with diuretics and excess water is useful for practical purposes when a human is accidentally exposed to tritium.View full abstractDownload PDF (566K) -
YUTAKA HAYASHI, ITARU YAMAGUCHI, MISAO KOBAYASHI, TAKASHI SHIMIZU, KAZ ...1990 Volume 31 Issue 4 Pages 375-388
Published: December 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSSubcutaneous administration of Z-100 twice a week starting immediately after supralethal whole-body irradiation of mice produced a prolongation of survival time. The effect of Z-100 on the hematopoietic system was thought to have contributed to the prolongation and was thus investigated. A single subcutaneous dose of Z-100 immediately after irradiation inhibited reduction of the total number of nucleated cells in the femoral bone marrow of the treated mice, although the inhibition was not by promotion of the proliferation of specific cells but by promotion of the recovery of multiple cell lines. Treatment with Z-100 promoted colony formation in the spleen of the treated mice and CFU-S formation in the femoral bone marrow, indicating that the drug accelerated the recovery of hematopoietic stem cells. The recovery of CFU-C count was also promoted by Z-100, which suggested that the drug has a restoring effect on the recovery of granulocytic and macrophagic precursor cells. Furthermore, Z-100 produed a greater increase in the CSF activity in the serum of irradiated mice, leading to the presumption that CSF induced by Z-100 was greatly involved in promoting the recovery of the above-mentioned hematopoietic stem cells.
We conclude that Z-100 prolonged survival time of irradiated mice by promoting recovery of hematopoietis of the mice.View full abstractDownload PDF (547K) -
NOBUKO MORI, YASUHIKO TAKAMORI1990 Volume 31 Issue 4 Pages 389-395
Published: December 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSSplit-dose X-irradiation efficiently induced Thy-l-positive thymic lymphomas (80%) in intact NFS mice within 12 months after irradiation. A high incidence (67%) of nonthymic lymphomas and leukemias was observed in the thymectomized NFS mice. Development of nonthymic lymphomas and leukemias in these mice started about 2 months later than that of thymic lymphomas and increased significantly 10 months onward after the last irradiation, when the development of thymic lymphomas in intact mice had already come to an end. These nonthymic lymphomas and leukemias involved predominantly the spleen and the mesenteric lymph nodes. Twelve out of 18 lymphomas and leukemias were examined immunocytologically. All of these tumors except one were diagnosed as lymphomas including one plasmacytoma. One case was diagnosed as myelomonocytic leukemia because the leukemic cells were highly positive for nonspecific esterase and negative for chrolacetate esterase. All lymphomas tested were negative for thy-1.2, and five of them expressed surface immunoglobulins. From these results, nonthymic lymphomas developed in thymectomized and X-irradiated NFS mice were classified as B-cell lymphomas probably including non-T/non-B cell lymphomas.
Present findings demonstrated that a low incidence of nonthymic lymphomas in intact NFS mice exposed to split-dose X-irradiation should be ascribed to a longer latency since most of the mice died of thymic lymphomas prior to the development of overt nonthymic lymphomas.View full abstractDownload PDF (295K) -
Katsuko SARUHASHI1990 Volume 31 Issue 4 Pages 397-399
Published: December 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSDownload PDF (129K)
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