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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 3
Displaying 1-7 of 7 articles from this issue
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NOBUO KUBOTA, TADASHI IKEGAMI, TAE IWASAWA, MASAE KAKEHI, KENGO MATSUI1990 Volume 31 Issue 3 Pages 235-245
Published: September 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSUsing plateau phase C3H 10T½ cells, we studied the effect of multiple-dose irradiation on the repair capacity of cells after further irradiation. Cells were irradiated with repeated doses of 2.5 Gy delivered two fractions per day at 6 to 7 hours interval. The cell survival after exposure to 1 to 9 fractions was lower above 5 fractions as compared to that predicted by calculating from single dose survival curve by assuming that cells retain their capacity to repair radiation damage after each fraction. Repair kinetics experiments showed that cells were less able to repair potentially lethal damage after test dose following multiple dose irradiations. There was, however, no difference in the ability to repair sublethal damage and potentially lethal damage sensitive to anisotonic treatment in preirradiated and untreated cells. Thus, it would appear that an enhancement of the lethal expression of potentially lethal damage of three types of damage may, at least in part, contribute to the difference between the cell survival curve after multiple fractions and that predicted by calculation.View full abstractDownload PDF (396K) -
YOSHIHISA KAWASE, SHINJI NAITO, MASAHIRO ITO, ICHIRO SEKINE, HIDEHARU ...1990 Volume 31 Issue 3 Pages 246-255
Published: September 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSLangerhans cells (LCs) are dendritic cells located in the epiderm is with antigen-presenting capacities. We performed a quantitative analysis of LC density in the anterior chest skin of 286 autopsy cases, including 31 cases treated with radiation therapy. Skin specimens were stained by immunoperoxidase technique (PAP method) with an anti-S-100 protein antiserum. S-100 positive LCs were counted for comparison between non-irradiated and irradiated cases. In this study we noted that, 1) The decline in density of the LCs was agerelated and dendritic processes were more prominent in younger groups. 2) The cases irradiated within one month before autopsy showed a reduction in LC density compared with age-matched controls. 3) The cases irradiated more than one month before autopsy demonstrated no consistent or definite tendency. It is suggested that ionizing irradiation as well as ultraviolet light may deplete the LC density in an acute phase. The possibility that radiation therapy alters immunological surveillance in the human skin is discussed.View full abstractDownload PDF (644K) -
MORIO YONEZAWA, ATSUHIKO TAKEDA, JUN MISONOH1990 Volume 31 Issue 3 Pages 256-262
Published: September 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSLow doses (2.5-15 cGy) of X-irradiation two months prior to a second exposure to a sublethal dose enhanced the survival rate in mice. Optimal and significant increase was observed with 5-10 cGy. Endogenous spleen colony counts (endo-CFUs) after 7 Gy increased by a factor of about 1.7 in mice pre-irradiated with 5-10 cGy, while the number of blood forming stem cells (CFUs) in the pre-irradiated group did not exceed that in the sham-irradiated control group at the period of the second exposure (two months after irradiation with 5 cGy). The low dose exposure seems to stimulate recovery of blood forming stem cells after the second irradiation and favors a decrease in the incidence of bone marrow death.View full abstractDownload PDF (251K) -
SENTARO TAKAHASHI, YOSHIHISA KUBOTA, HIROSHI SATO1990 Volume 31 Issue 3 Pages 263-269
Published: September 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSThe effect of external γ-irradiation on the digestive function of rat alveolar macrophages (AM) was studied by using the in vitro assay system, where the 59Fe release from AM engulfing 59Fe-iron hydroxide colloid was measured as an indicator of their digestive capability. Graded doses of γ-irradiation up to 100 Gy had no effect on the extracellular release of 59Fe in AM cultured at 4 and 37°C for 8-72 hrs postirradiation. When 10 mM Ca-DTPA was added to the culture medium, the 59Fe release was slightly depressed by irradiation at a dose of 30 Gy. It is apparent from these results that γ-irradiation had no effect on the 59Fe transfer between cell and medium, and little effect on the catabolism of 59Fe-colloid in rat AM.View full abstractDownload PDF (328K) -
ETSUKO KUMAGAI, RYUJI TANAKA, TAKASHI KUMAGAI, MITSUKAZU ONOMICHI, SHO ...1990 Volume 31 Issue 3 Pages 270-279
Published: September 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSChromosomal aberrations in the lymphocytes of radiation technologists (RT) were analyzed by the trypsin G-banding method to study the late effects of long-term exposure to low doses of radiation. Structural aberrations were identified in 384 (2.5%) of 15442 cells analyzed from 53 RT as compared to 177 (1.6%) of 11136 cells from 36 healthy controls. Stable aberrations were the most frequent in both groups and were either translocations or deletions. Unstable aberrations were mainly acentric fragments in both groups. The frequency of translocations and acentric fragments was significantly higher in the RT than in the controls and was highest in the RT over 50 years. The highest frequency observed in the >50 age group was attributed to the unknown for cumulative dose prior to introduction of film badges. Frequency of chromosomal aberrations correlated with the estimated dose from the film badges and years of experience of each RT based on the equation y=0.22+0.37D+4.35D2, where y is overall frequency of chromosomal aberrations and D is the estimated radiation dose in Sv.View full abstractDownload PDF (390K) -
NAOKI SADAMORI, MARIKO MINE, MAKOTO HORI, NAOKO FUJIWARA, OSAMU TAKAHA ...1990 Volume 31 Issue 3 Pages 280-287
Published: September 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSAmong a total of 65, 268 Nagasaki atomic bomb survivors recorded in the Scientific Data Center of Atomic Bomb Disaster, Nagasaki University School of Medicine, 140 cases with skin cancer were collected from 31 hospitals in Nagasaki City from 1961 through 1987. Subsequently, these cases of skin cancer in Nagasaki atomic bomb survivors were statistically analyzed in relation to the estimated distance from the hypocenter by age, sex, histology and latent period. The results were as follows: 1. A high correlation was observed between the incidence of skin cancer and the distance from the hypocenter. 2. The incidence of skin cancer in Nagasaki atomic bomb survivors now appears to be increasing in relation to exposure distance. 3. Among 140 cases, basal cell epithelioma was observed in 67 cases (47.9%) and squamous cell carcinoma in 43 cases (30.7%).View full abstractDownload PDF (346K) -
TAISEI NOMURA, YOUSUKE TAKAHAMA, TADASHI HONGYO, HIDENORI INOHARA, HIR ...1990 Volume 31 Issue 3 Pages 288-292
Published: September 15, 1990
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSIn severe combined immunodeficiency (scid) mice which are deficient in T and B cell functions, human yolk sac tumor (YST-2) grew rapidly to enormous sizes in all of the animals after both subcutaneous and intraperitoneal transplantation, while only half of the subcutaneous and none of the intraperitoneal transplants were accepted in usual athymic nude mice. Furthermore, transplanted tumors metastasized spontaneously to distant organs such as lung, liver, kidney, pancreas, and spleen in scid mice, while metastases were not found in athymic nude mice. Similar results were observed in scid mice and scid-nude (streaker) double mutant mice with human classic (typical) seminoma which has been neither transplantable nor metastatic in athymic nude mice. Thus, scid mice provide an invaluable experimental system to investigate the mechanism of metastasis which is the most important and life-threatening problem in cancer patients.View full abstractDownload PDF (294K)
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