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Volume 24 (1983)
- Issue 4 Pages 285-
- Issue 3 Pages 197-
- Issue 2 Pages 137-
- Issue 1 Pages 109-
Volume 24, Issue 4
Displaying 1-8 of 8 articles from this issue
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Y. TAKAGI, M. SHIKITA1983 Volume 24 Issue 4 Pages 285-290
Published: December 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSMitotic cells disappeared nearly completely within 60 min after the addition of 30 mM cysteamine in HeLa S-3 cell culture, while the control culture contained mitotic cells with the frequency of 3.4%. Inhibition of mitosis became gradually irreversible when the treatment was extended over 60 min, but cytolysis occurred much more slowly. Ethanolamine exhibited a similar but much less significant effect.View full abstractDownload PDF (256K) -
KIMIO TANAKA, NANAO KAMADA, TAKESHI OHKITA, ATSUSHI KURAMOTO1983 Volume 24 Issue 4 Pages 291-304
Published: December 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSThe distribution of breakpoints within chromosomes in lymphocytes of 39 healthy atomic bomb survivors who were heavily exposed were studied by means of G and Q-banding techniques. A total of 1, 414 breakpoints in 651 cells with structural chromosome aberrations were used for the present analyses. The results obtained were as follows: (1) In chromosomes #15, #18 and #22, the breaks were more frequently observed than expected. On the contrary, the number of breaks among chromosomes #1, #2 and X was less than expected. (2) A higher incidence of breakpoints according to the length of regions in 4q3, 5q3 and 14q3 and a lower incidence in regions around centromeres of large chromosomes were observed. (3) Distribution of breakpoints was 26.6% in the centromeric region, 30.8% in the middle region and 42.6% in the telomeric region. (4) Seventy-four percent of the breaks was observed in the negative bands. The present results clearly show that breakpoints in atomic bomb survivors were not randomly distributed interchromosomally as well as intrachromosomally. Detailed chromosome analyses have elucidated the biological significance of chromosome aberrations particularly in relation to the late effects among atomic bomb survivors.View full abstractDownload PDF (834K) -
HIROAKI WAKABAYASHI, SHOZO SUZUKI, AKIRA ITO1983 Volume 24 Issue 4 Pages 305-316
Published: December 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSRadiation biology and/or therapy research and development for a research reactor beam need specific RBEs of neutrons as well as of specific reactions. RBEs for reactor beams measured in situ condition are interesting because actual radiation effects on each biological system are different depending on detailed conditions of irradiation. A small powered research reactor (Fast Neutron Source Reactor: YAYOI) was examined here as a neutron beam source for obtaining survival curves in a manner usually done for cyclotron neutron source and 60Co gamma rays. Chinese Hamster Cells were chosen as a sample system for comparison among them.
With an assumption of independence among individual radiation (neutron and gamma ray) effects and with the nearly equal survival fraction relation for 60Co and reactor gamma, all the data taken for different radiation field were found to be fitted by a single curve with a set of Do and m value for the hit theory.View full abstractDownload PDF (298K) -
KIYOMI EGUCHI, SHINICHIRO SATOH, MAKIKO YAGUCHI, TETSUO INADA1983 Volume 24 Issue 4 Pages 317-325
Published: December 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSThe hyperthermic modification of radiation effect on cell inactivation should be important role for cancer therapy. This work has been done to obtain the DNA-scision and -repair relevant to the cell death and to recovery of clonogenesity after preirradiation heating at 42°C where heat effect on cell death has not been severe. Radiation inactivation of human melanoma cultured cells (HMV-I) has been synergetically enhanced by the preirradiation heating at 42°C. The DNA lesion has been detected by the alkaline elution method. The amount of initial lesion for cells heated before irradiation seemed to be less than those for X-ray alone irradiated cells. This result may be relevant to the crosslinking or aggregation introduced in DNA strand after the heat treatment. Recovery capacity of cell clonogenic damage after irradiation was considerably reduced by post-irradiation heat treatment. Time course of DNA damage repair after irradiation was similar to that of recovery of clonogenesity. These results indicate that mild hyperthermic treatment inhibit the repair of DNA damage caused by irradiation.View full abstractDownload PDF (345K) -
YASUYUKI MURAMATSU, DIRK CHRISTOFFERS, YOICHIRO OHMOMO1983 Volume 24 Issue 4 Pages 326-338
Published: December 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSUptake of iodide and iodate by komatsuna, Brassica Rapa var. pervidis, was studied using culture solution containing radioiodine as a tracer. After 24 hours'' exposure, accumulation of iodide in the plant was several times higher than that of iodate. The concentrations of both iodide and iodate in roots were much higher than those in shoots. It was estimated that high accumulation of iodide in roots was due to the adsorption of the element on the root surface. The plant of the earlier growth stage absorbed iodide selectively from the solution. On the contrary that of the older growth stage, more than 40 days after seeding, showed less absorption of the element.
Influence of stable iodine content on the uptake of radioiodine was also examined. The transfer rate of radioactive iodide to roots decreased remarkably with increasing amount of stable iodide in the culture solution, whereas that to shoots remained relatively constant indicating that the element content in shoots increased almost proportionally with the increasing concentration of stable iodine in the solution.
A significant amount of iodate in the culture solution was transformed to iodide in the presence of plant. The dominant chemical form of iodine in the plant was thought to be iodide.View full abstractDownload PDF (510K) -
KUNIO SHINOHARA, YOSHIO INOUE, KAZUO YAMAMOTO1983 Volume 24 Issue 4 Pages 339-344
Published: December 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSHeLa cells were allowed to become attached to a membrane filter and then irradiated with UV radiation at 254 nm. The viability of the cells was lower than that of cells which were irradiated on a plastic Petri dish. This decrease in viability was observed not only when the cells were in direct contact with the membrane filter, but also when the membrane filter was placed outside the Petri dish containing the HeLa cells which allowed the transmission of UV. Experiments with T4 phage in suspension strongly suggest that this decrease in viability is due to the reflection of 254 nm radiation by the membrane filter.View full abstractDownload PDF (249K) -
TAKEHIKO TSUCHIYA, TOSHIYUKI NORIMURA, MIEKO OKAMOTO1983 Volume 24 Issue 4 Pages 345-355
Published: December 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSThe immunological activity of the host after tumor irradiation was investigated in in vivo and in vitro system. The spleen cells from tumor irradiated mice inhibited growth of tumor in mice which were inoculated tumor cells together with these spleen cells. These spleen cells also inhibited the colony formation, and tumor growth in in vitro system. The cytostatic activity of spleen cells against tumor cells was enhanced after local tumor irradiation. It was also shown that enhancement of specific anti-tumor cell-mediated immunity of spleen cells in host occurred 7 or more days following local irradiation to tumor and continued for several weeks.View full abstractDownload PDF (363K) -
TOYO OKUI, YOSHISADA FUJIWARA1983 Volume 24 Issue 4 Pages 356-363
Published: December 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSOptimally activated aflatoxin B1 (AFB1), 3-amino-l, 4-dimethyl and 3-amino-l-methyl-5H-pyrido[4, 3-b]indoles (Trp P-1 and Trp P-2) exerted more lethal effects on xeroderma pigmentosum (XP) complementation group G cells than on normal human ells. XP group G cells exhibited deficiency in unscheduled DNA synthesis and in accumulation of arabinofuranosyl cytosine/hydroxyurea-induced single strand breaks after treatment with the three agents. Thus, Trp P-1 or Trp P-2 damage can be repaired mainly by nucleotide excision repair, as found with AFB1 damage. Activated AFB1 induced more sister chromatid exchanges (SCEs) in XP group G cells than in normal cells, while such a differential response to SCE was not observed with activated Trp P-1 and Trp P-2.View full abstractDownload PDF (371K)
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