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Volume 17, Issue 3
Displaying 1-9 of 9 articles from this issue
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Y. SUZUKI, R. NAKAMURA, T. UEDA1976 Volume 17 Issue 3 Pages 115-126
Published: September 15, 1976
Released on J-STAGE: July 14, 2006
JOURNAL FREE ACCESSIn order to know factors which influence 60Co contamination of sargassoes in Urazoko Bay, where a nuclear power plant is located, correlations between the contaminations of the algae and of the marine environment were examined, based on field data observed since January 1971.
It was found that; [1] correlation between the 60Co concentration in sargassoes (YaigaepCi/kg raw weight) and distance from discharge outlet of the nuclear power plant to the sampling points (d km) was expressed by a function, Yaigae=C·exp(-kd), where C and k are constants, and k increased successively from 0.388 in Nov. 1971 to 1.200 in Nov. 1974, whereas C decreased from 120 to 27 during the same period. [2] 60Co content in the sargassoes seemed to be contributed dominantly by the dislodged 60Co from heavily contaminated sediment rather than freshly discharged 60Co from the power plant. The amount of dislodged 60Co was estimated from both the 60Co distribution in marine sediment in Urazoko Bay and results of a tracer experiment concerning the dislodgement of 60Co from marine sediment.View full abstractDownload PDF (354K) -
M. POLVERELLI, A. BONICEL, R. TEOULE1976 Volume 17 Issue 3 Pages 127-134
Published: September 15, 1976
Released on J-STAGE: July 14, 2006
JOURNAL FREE ACCESSThe radiolysis products resulting from the cleavage of the N-glycosidic linkage after gamma irradiation of cytosine 14C-2 labelled DNA of Escherichia coli were mainly cytosine and trans 5, 6-dihydroxy-5, 6 dihydro uracil. Relative percentages of these products were determined against doses and mechanism of release suggested.View full abstractDownload PDF (302K) -
KHALIL GHOLIPOUR KHALILI, KENJI TAKESHITA1976 Volume 17 Issue 3 Pages 135-141
Published: September 15, 1976
Released on J-STAGE: July 14, 2006
JOURNAL FREE ACCESSMouse leukemic cells (L5178Y) were used to determine the RBE values of high energy electron beams at various depth doses in a water phantom at 37°C. The RBE values of 10, 20 and 30 MeV electrons relative to 180 kV X-rays were 0.77, 0.83 and 0.86 at 100% depth dose, respectively.
The RBE values of 30 MeV electrons were 0.85 at 95%, near the surface, and 0.89 at 68% depth doses. At 18% depth dose, a 0.78 RBE value was detected.View full abstractDownload PDF (230K) -
HITOSHI MICHIBATA1976 Volume 17 Issue 3 Pages 142-153
Published: September 15, 1976
Released on J-STAGE: July 14, 2006
JOURNAL FREE ACCESSAdult males of the fish Oryzias latipes were irradiated with 0.5 or 1 kR of 137Cs-gamma-rays (100 R/min). From the viewpoint of the cell-population shift and cell differentiation, the radiation effects on the spermatogenesis in the testis were analyzed. Among the three types of spermatogonia, the first type, the spermatogonia As, were very resistant to radiation, judging from the survival of the cells, but the other types, the spermatogonia Ad and the spermatogonia B, were sensitive to radiation. The spermatogonia As began to proliferate after the degeneration and disappearance of the spermatogonia Ad following the irradiation. During the proliferation phase of the cells, some of the spermatogonia As were morphologically transformed into the spermatogonia Ad, which contributed to the repopulation of the spermatogenetic cells in the testis following the cell loss induced by radiation damage.View full abstractDownload PDF (493K) -
O. NIKAIDO, M. HORIKAWA1976 Volume 17 Issue 3 Pages 154-173
Published: September 15, 1976
Released on J-STAGE: July 14, 2006
JOURNAL FREE ACCESSThe factors in determining radiosensitivity of cultured mammalian cells were analysed by using two clones each having different radiosensitivities. The radiosensitive clones were isolated from HeLa S3 cells by the N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-treatment, X-irradiation (200R) and 5-bromodeoxyuridine (BUdR)-visible light method. On the other hand, the radioresistant clone was isolated by single X-irradiation (2000R) from MNNG-treated HeLa S3 cell population. The radiosensitivities expressed in Do and Dq values were 110 and 140 R in radiosensitive SM-1a clone and 180 and 230 R in radioresistant RM-1b clone respectively. The biological and biochemical characteristics of both clones such as the distribution of chromosome numbers, formation and rejoining of single strand breaks in DNA caused by X-irradiation, non-protein sulfhydryl (NPSH) and apparent total sulfhydryl (APSH) contents were measured. Among the characteristics analysed, different contents of NPSH in the cells were well correlated to their radiosensitivities among the original HeLa S3 cells, SM-1a and RM-1b clones. Additionally, it was found that the radioresistant L·P3 Co-3 cells isolated by Tsuboi et al. from the original mouse L·P3 cells by means of serial irradiation with 60Co γ-rays have more abundant NPSH than the original L·P3 cells. From these results, it can be concluded that the amount of NPSH play the main role in determining radiosensitivity in cultured mammalian cells.View full abstractDownload PDF (715K) -
Y. UENO1976 Volume 17 Issue 3 Pages 174-181
Published: September 15, 1976
Released on J-STAGE: July 14, 2006
JOURNAL FREE ACCESSThe effect of intraperitoneal injection of N1-(2'-tetrahydrofuryl)-5-fluorouracil (FT-207) which is metabolized to 5-fluorouracil (5-FU) in vivo, on endogenous colony forming units in the spleen (endogenous CFU-s) was observed and compared with that of 5-FU. The 8×10-4 m eqv of FT-207 injected in mice 20 minutes before X-rays irradiation of 450 rads suppressed the endogenous CFU-s count to about 60% and about 5.5×10-5 m eqv of 5-FU had the same effect. The suppression of FT-207 continued over 120 minutes and increased gradually. The effect of 5-FU was strong shortly after the injection but faded out for 120 minutes. FT-207 had almost no effect on the recovery constant (Blair) of endogenous CFU-s for 3 days, whereas 5-FU reduced seriously, especially for the first 2 days. The differences in the effects of both compounds could not be explained on the base of the only differences in the metabolism of both compounds.View full abstractDownload PDF (330K) -
SHOZO SUZUKI1976 Volume 17 Issue 3 Pages 182-191
Published: September 15, 1976
Released on J-STAGE: July 14, 2006
JOURNAL FREE ACCESSIn order to clarify the sites in a cell which were susceptible to oxygen effect by radiation, its effect on the membrane permeability of sheep erythrocytes was investigated with 200 kVp X-rays and 6 MeV cyclotron neutrons in the presence and absence of oxygen. Radiation damage to membranes, irradiated at room temperature and stored for 20 hours at 4° and 37°C, was assessed from both the escape of K+ from the cells and the incorporation of Na+ into the cells. The values of OER (oxygen enhancement ratio) and RBE (relative biological effectivenss) for the damage by neutrons at 4°C were 1.0 and 3.1, respectively. The same value of OER was obtained by X-rays. No oxygen effect was also observed even at 37°C where the repair of damage to membranes existed.
These results are incompatible with the model that membranes are sites of type ‘O’ damage susceptible to oxygen effect.View full abstractDownload PDF (376K) -
H. JOSHIMA, M. KASHIMA, O. MATSUOKA1976 Volume 17 Issue 3 Pages 192-203
Published: September 15, 1976
Released on J-STAGE: July 14, 2006
JOURNAL FREE ACCESSThe changes in erythrocyte counts, hematocrit, hemoglobin, reticulocyte counts and erythrocyte survival following an intravenous injection of polymeric 239Pu at the does level of 15 μCi/kg, 10 μCi/kg and 5 μCi/kg were studied in CF # 1 male mice in order to investigate the possible pathogenesis of anemia produced by irradiation of polymeric plutonium. The administration of 15 μCi/kg and 10 μCi/kg of polymeric plutonium produced anemia but 5 μCi/kg had no significant effect. Studies with 51Cr labelled erythrocyte showed a moderate reduction in survival of erythrocyte following a single intravenous injection of polymeric plutonium. Not only the intracorpuscular effect but also extracorpuscular effect of polymeric plutonium was considered to lead to a reduction in erythrocyte survival, but no clear dose relationship could be observed between the reduction of survival and either intracorpuscular effect or extracorpuscular effect. Although the most important pathogenesis of anemia produced by polymeric plutonium is supposed to be a decreased erythropoiesis, it was believed that both qualitatively impaired erythropoiesis and abnormal erythrocyte destruction might also play some role in the occurrence of anemia.View full abstractDownload PDF (461K) -
T. KITABATAKE, T. SATO, S. TAKEUCHI1976 Volume 17 Issue 3 Pages 204-210
Published: September 15, 1976
Released on J-STAGE: July 14, 2006
JOURNAL FREE ACCESSFrequency of prenatal X-ray examination in 1, 701 parturient women was surveyed in 19 Japanese hospitals in 1974. Of 1, 701 women, 470 or 27.6% have received maternal X-ray examination during the pregnant period. There is no significant difference in frequency of prenatal X-rays between in the primipara and multipara. Chest examination was frequent in the 3rd to 6th month of gestation, while a pelvimetric study was performed mainly after the 10th month. About 82% of the fetal dose was contributed from a prenatal pelvimetric study. The fetus receives averagedly 202 mrad of radiation from the prenatal X-ray examinations. It is calculated that about 6.3 leukemias may be induced yearly by maternal X-ray. This corresponds to about 1% of leukemias in the same generation.View full abstractDownload PDF (234K)
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