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Volume 28 (1987)
- Issue 4 Pages 233-
- Issue 3 Pages 191-
- Issue 2 Pages 141-
- Issue 1 Pages 109-
Volume 28, Issue 3
Displaying 1-5 of 5 articles from this issue
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GENSAKU OKADA, HIDEKI MITSUI, ICHIRO KANEKO1987 Volume 28 Issue 3 Pages 191-203
Published: September 15, 1987
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSThe effects of nicotinamide (NA) deficiency and added NA and 3-aminobenzamide (3AB) on the cytotoxicity and the induction of mutations in Chinese hamster V79-14 cells were investigated. In NA deficiency the addition of NA (up to 4 mM) and 3AB (up to 7.5 mM) was not cytotoxic. The presence of NA prior to exposure to mitomycin C (MMC) or γ-rays produced a dose-dependent increase in the relative cloning ability of DNA-damaged cells. The lethality of N-methyl-N''-nitro-N-nitrosoguanidine (MNNG) was significantly potentiated by pre-treatment with 5 mM 3AB, but no potentiation by 3AB was observed for MMC, ultraviolet (UV)-B light, or γ-rays.
Among cells pre-cultured in NA-free medium there were increased frequencies of mutations at both the hypoxanthineguanine phosphoribosyltransferase (HGPRT) and the adenine phosphoribosyltransferase (APRT) loci following DNA damage. The enhancing effect by NA deficiency was time-dependent. Incubation with NA prior to DNA damage produced a significant reduction in the frequency of mutations. The addition of 3AB to the nicotinamide adenine dinucleotide (NAD+)-depleted cell cultures before or after the DNA damage also strongly increased the frequency of induced mutations, with increasing concentrations of 3AB up to 5 mM, but the frequency was reduced at higher concentrations. The interaction between NA deficiency and the addition of 3AB appears to act synergistically on mutation induction. A correlation was observed between the potential of inhibiting poly (ADP-ribose) polymerase and the enhancement of mutation frequency.View full abstractDownload PDF (626K) -
HISAMASA JOSHIMA, SATORU MATSUSHITA, KUMIKO FUKUTSU, MASATOSHI KASHIMA1987 Volume 28 Issue 3 Pages 204-212
Published: September 15, 1987
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSTo derive parameters necessary for evaluating the possible hazards of tritium, retention of tritium in total and TCA-insoluble fractions of the femoral marrow and spleen of mice were observed after single intravenous injections of tritiated water and tritiated thymidine. Retention curves of tritium in TCA-insoluble fractions of the femoral marrow and spleen were resolved fairly well into two exponential components.
After injecting tritiated thymidine, most of the activity was detected in the TCA-insoluble fraction. Tritium in this fraction decreased with half-times of 2.2 days in the femoral marrow and 3.6 days in the spleen as the first component, and 23.9 days and 30.5 days, respectively, as the second component.
After tritiated water injections, the tritium incorporated into the TCA-insoluble fraction was quite small. Most of the activity was considered to be in the TCA-soluble fraction. Tritium in this fraction was estimated to decrease with half-times of 2.6 days in the femoral marrow and 2.3 days in the spleen as the first component, and 8.0 days and 8.2 days, respectively, as the second component. It is concluded that the retention curves of tritium in the bone marrow are similar to those in the spleen for tritiated water, but not for tritiated thymidine.View full abstractDownload PDF (404K) -
KIYOMI EGUCHI-KASAI, TOSHIFUMI KOSAKA, ICHIRO KANEKO, TAN TAKAHASHI, A ...1987 Volume 28 Issue 3 Pages 213-220
Published: September 15, 1987
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSDNA strand breaks were induced by N-ion beam (LET∞ = 530 keV/μm) in HMV-I cells, derived from a human malignant melanoma, and were studied using the alkaline elution method. The DNA strand breaks which were detected included single strand breaks, double strand breaks, and alkaline labile sites. The DNA strand breaks increased linearly with 60Co γ-ray doses. Most of these breaks were rejoined during post-irradiation incubation at 37°C; the remainder were considered non-repairable. Non-repairable DNA strand breaks increased quadratically with increases in 60Co γ-ray doses. However, DNA strand breaks increased nearly linearly with increases in doses of N-ions, even after post-irradiation incubation. These correlations of doses with non-repairable DNA strand breaks were similar to those of doses versus cell survival.View full abstractDownload PDF (301K) -
KAORI TATSUGAWA, NORI NAKAMURA, MASAYUKI HAKODA, MITOSHI AKIYAMA1987 Volume 28 Issue 3 Pages 221-226
Published: September 15, 1987
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSIn vitro culture conditions for colony formation of human fresh peripheral T-cells using PHA and recombinant Interleukin-2 are defined. Peripheral lymphocytes, from six individuals, were exposed to X or gamma rays in vitro, and dose-survival curves were obtained. The results showed typical sigmoid curves similar to those observed when other mammalian cells are exposed to radiation. The D10 (dose required to kill 90% of the cells) was found to be 3.0 to 3.5 Gy.View full abstractDownload PDF (249K) -
SENTARO TAKAHASHI, SHOKO ASAHO, YOSHIHISA KUBOTA, HIROSHI SATO, OSAMU ...1987 Volume 28 Issue 3 Pages 227-231
Published: September 15, 1987
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSIn this study, the transportability of ultrafine particles from the lung to the regional lymph nodes was investigated. 198Au-colloid particles with 0.02 μm count median diameter (CMD) and 133 BaSO4 particles with 0.39 μm CMD were instilled into rat lungs via intratracheal cannulas. Both the 198Au-colloid and the 133BaSO4 were distributed mainly to the posterior mediastinal lymph nodes. There were no significant differences between the quantities of the 198Au-colloid and 133BaS04 particles which reached the regional lymph nodes. This suggests that the mode of transporting ultrafine particles such as 198Au-colloid from the lung to regional lymph nodes is similar to that of particles in the micrometer size range.View full abstractDownload PDF (252K)
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