• 대한방사선기술학회지:방사선기술과학
• /
• 제25권2호
• /
• pp.77-82
• /
• 2002

이미 분화된 연골세포의 성숙과정에 미치는 X-선의 작용에 대해서는 잘 알려져 있다. 그러나 연골세포나 섬유아세포, 근육세포로 분화될 수 있는 미분화 간충직 세포의 분화과정에 미치는 X-선의 영향에 대해서는 잘 알려져 있지 않아, 본 연구에서는 초기 분화연구에 좋은 대상이 되는 계배 미분화 간충직세포를 이용하여 선량(1-10Gy)에 따라 연골세포 분화 과정에 X-선이 어떤 영향을 미치는가를 조사하였다. 연구결과 선량 의존적으로 연골세포분화가 억제됨을 alcian blue로 sulfated proteoglycan을 염색한 결과를 통해 알 수 있었다. 이는 X-선이 간충직세포와 같은 성숙 이전의 연골성 세포들에게는 모두 영향을 미침을 보여주는 것이다. 또한 이미 알려진 바와 같이 X-선은 분화된 연골세포의 성숙과정에 영향을 주기도 하지만 상기 연구를 통해서 간충직세포로부터 연골세포로 분화하는 과정을 억제시키기도 함을 보여줌으로써 간충직세포로부터 성숙된 연골세포로 되는 전과정에 X-선이 영향을 미친다는 사실과, 분화가 이루어지지 않은 세포일수록 X-선 조사의 영향을 크게 받음을 알 수 있다.

• 치과방사선
• /
• 제11권1호
• /
• pp.33-40
• /
• 1981

The author studied on the effects of x-irradiation to the development of digital malformation in gestation rats. The time-matings occured between 6 p.m. and 8 a.m. and females with copulation. plugs at 8 a.m. were isolated and properly marked for evidence of copulation. The lower abdomen of mothers were exposed to x-irradiation on the 11½th day of gestation, the critical period developing digital malformation, respectively 100, 150, 200, 250, 300 and 350 rads. At 18½th day of post-conception total 50 pregnant females were dissected and the incidence of digital malformations were obtained. Rat embryos on the 12, 13, 14, 15, 16th day of gestation irradiated by 250 rads were examined for morphogenesis of digital malformation. Digital radiating lines were examined in water and histologically by H-E stain. Supra vital stain samples by Nile-blue sulfate in 37℃ normal saline were prepared for the observation of cell necrosis regions and morphogenesis of digits. The results obtained were as follows; 1. By x-irradiation on 11th day of gestation, digital malformations of Ectrodactylia, Syndactylia Polydactylia and Hematodactylia were developed. Ectrodactylia showed the effective relationship to the amount of irradiation, however Syndactylia ans Polydactylia did not. 2. By x-irradiation, cell necrosis of digital germ was appeared markedly, but in 48 hours after irradiation was depressed to the periphery of digital germ and in 72hours after irradiation was disappeared. Digital radiating line showed marked stage of malformation in 48hours after irradiation and continued to show the same amount of physiological cell necrosis as the compared control group in 72hours. after irradiaion. But in the Syndactylia, physiological cell necrosis was not able to be recognized. 3. Ectrodactylia induced by x-irradiation was considered as the direct resoult of cell necrosis of digital origin, however, Polydactylia and Syndactylia were considered as the resoult of some effect in repair process of x-irradiation damages.

• 한국동물학회지
• /
• 제11권3호
• /
• pp.75-82
• /
• 1968

培養 HeLa 細胞의 酸素消費量과 Lysine 吸收에 미치는 X-線 照射의 영향을 측정하였다. 1. 200r의 X-線 照射는 酸素消費量에 아무러한 영향이 없다. 酸素消費量은 succinate, citrate, 및 $\\alpha$-ketoglutarate에 의하여 增大되며 X-線 照射群에서도 이 傾向은 同一하다. 2. 酸素消費量에 미치는 sodium azide 와 2,4-dinitrophenol 의 영향은 X-線 照射에 의하여 상당히 변화된다. 3. Lysine의 初期吸收率은 X-線 照射에 의하여 甚히 低下되며, 또한 飽和吸收量도 減少된다. 4. Glucose는 lysine의 吸收를 促進시키고, succinate는 아무러한 영향이 없으며 citrate와 $\\alpha$-ketoglutarate는 억제한다. X-線 照射는 이러한 傾向에 아무런 변화를 초래하지 않는다. 5. Lysine의 吸收에 미치는 sodium azide와 2,4-dinitrophenol의 영향은 酸素消費量에 미치는 이들의 영향과 判異하다. 이러한 傾向은 X-線 照射群에서도 대체로 동일하다.

• 식품과학과 산업
• /
• 제53권3호
• /
• pp.264-276
• /
• 2020

Ionizing radiation is one of the efficient non-thermal pasteurization methods. The US Food and Drug Administration (FDA) allows the use of ionizing radiation to a dose up to 10 kGy for controlling foodborne pathogens and extending the self-life of foods. Recently X-rays, generated on absorption of high energy electrons in an appropriate metal target, have been used commercially for sterilization purposes. X-rays have the advantages of higher penetration power than E-beams and absence of harmful radioactive sources, such as Cobalt-60 or Cesium-137 associated with gamma-rays. That is why it has continued to receive attention as an attractive alternative to gamma-ray or E-beam irradiation. In this article, the potential of X-ray irradiation for controlling foodborne pathogens in various food products and necessary pre-requisite knowledge for the introduction of X-ray irradiation to the Korean food industry will be provided.

• Journal of Photoscience
• /
• 제9권2호
• /
• pp.209-212
• /
• 2002

Cutaneous hyperpigmentation is a well-known consequence of both acute and chronic X-irradiation, although the molecular mechanisms involved are not well understood. Recently, protein kinase C-$\beta$ (PKC-$\beta$) was shown to activate tyrosinase, a key and the rate-limiting enzyme in melanogenesis [1]. In this study, we have investigated its role in mediating ionizing radiation-induced pigmentation by exposing cultured human melanocytes to X-irradiation. Increased tyrosinase activity after the 4 Gys exposure was observed within 48 hrs and total melanin content doubled after 7 days. Interestingly, tyrosinase mRNA level was not affected by X-irradiation. However, there was a 2-3 fold increase in PKC-$\beta$ mRNA after 48 hours of irradiation, coinciding with the increase in tyrosinase activity. This induction was not due to non-specific heat generated during the irradiation because when melanocytes were incubated at 4$0^{\circ}C$, there was no induction of PKC-$\beta$ mRNA. Taken together, these data suggest that X-irradiation induces cutaneous hyperpigmentation, at least in part, by up-regulating the level of PKC-$\beta$.

• Nuclear Engineering and Technology
• /
• 제56권1호
• /
• pp.114-122
• /
• 2024

Irradiation-induced defects and the precipitates in the wrapper material of the Indian Fast Breeder Test Reactor (FBTR), SS 316 are analyzed using the synchrotron source-based Angle Dispersive X-Ray Diffraction (ADXRD) technique with X-rays of energy 17.185 keV (wavelength ~0.72146 Å). The differences and similarities in the high displacement damage samples as a function of dpa (displacement per atom) and dpa rate in the range of 2.9 × 10^-7- 9 × 10^-7 dpa/s are studied. Ferrite and M₂₃C₆ are commonly observed in the present set of high displacement damage 40-74 dpa SS 316 samples irradiated at temperatures in the range of 400-483 ℃. Also, the dislocation density has increased as a function of the irradiation dose. The X-ray diffraction peak profile parameters quantified such as peak shift and asymmetry show that the irradiation-induced defects are sensitive to the dpa rate-irradiation temperature combinations. The increase in yield strength as a function of displacement damage is also correlated to the dislocation density.

• The Korean Journal of Physiology
• /
• 제5권2호
• /
• pp.55-62
• /
• 1971

In an attempt to better understand the effects of whole body X-irradiation on the levels of non-protein sulfhydryl (NP-SH), non-protein disulfide (NP-SS) and oxygen consumption rate $(QO_2)$ of the mouse duodenum, and to clarify the possible radioprotective action of reduced glutathione (GSH), a whole body X-irradiation of 1,000r was given to albino mouse either singularly or immediately after injecting GSH intraperitoneally to mouse 1 mg per gm of body weight. NP-SH was measured by Ellman's method, NP-SS was measured by the electrolytic reduction method described by Dohan and Woodward, and $(QO_2)$ by the Warburg's standard manometric method. The experiment was performed at 1, 6, 12 and 24 hours post-irradiation, and the comparison was made with the control. The results thus obtained are summarized as follows: 1) Comparing with the intrinsic NP-SH level of $3.31{\pm}0.27{\mu}\;mol/gm$ wet weight in the duodenum of the normal mouse, either whale body X-irradiation or injection of GSH alone produced no significant change in NP-SH from the normal. However, when GSH was injected prior to X-irradiation, markedly elevated NP-SH levels were observed throughout the entire experiment with the highest value of $4.70{\pm}0.10$ at 6 experimental hours. 2) The normal value of NP-SS in the mouse duodenum was $1.57{\pm}0.17{\mu}\;mol/gm$ wet weight, while in the group where injection of GSH and X-irradiation were combined, NP-SS increased to $2.36{\pm}0.33$ at 12 hours and $2.15{\pm}0.53$ at 24 hours, showing the intermediate value between the GSH injection group and X·irradiation group. 3) The normal value of $(QO_2)$ was $4.16{\pm}0.73{\mu}l\;O_2/hr./gm$ D.W., and no noticeable change was observed comparing with the GSH injection group. However, in the group where X·irradiation alone was given, $(QO_2)$ of the duodenum increased significantly throughout the entire experiment with the highest value of $6.35{\pm}1.07$ at 6 experimental hours. When GSH was injected before X-irradiation was given, the levels of $(QO_2)$ were in the middle of the GSH injection group and X-irradiation group. 4) The above results suggest that GSH may be effective as a radioprotector in terms of NP-SH, NP-SS and $(QO_2)$ of the mouse duodenum.

• Radiation Oncology Journal
• /
• 제18권2호
• /
• pp.133-137
• /
• 2000

목적 : 베타카로틴과 방사선조사의 병용효과에 관한 평가를 목적으로, 베타카로틴을 병용한 경우 방사선조사 단독의 경우 보다 세포독성의 차이는 어떠하며, 또한 쥐 섬유육종에서 두 군간의 종양성장의 지연 정도에 어떠한 차이가 있는가를 관찰하고자 본 연구를 시행하였다. 대상 및 방법 : 2$\%$ 베타카로틴 유제를 2 mg/ml 으로 만든 다음 단계적으로 희석하여 사용하였으며, 섬유육종세포와 태생 5~6주의 C3H/N의 실험쥐를 이용하였다. 방사선조사는 6 MV 선형가속기를 이용하였고, 세포내 독성은 쥐 섬유육종세포의 생존을 감소시키는 능력으로 평가하였으며, 베타카로틴 2 mgfml을 방사선조사 1시간 전 섬유육종세 포주에 접촉시켰다. 종양성장 지연 실험을 위하여 베타카로틴과 방사선조사 병용군(n=6)과 방사선조사 단독군(n=5)으로 분류하였으며, 베타카로틴 20 mg/kg을 방사선조사 30분전 섬유육종이 접종된 쥐의 복강내 일회 주사하였고, 방사선조사량은 20 Gy를 주었다. 종양용적은 장경$\times$장경$\times$장경/(mm$^{3}$) 공식을 사용하였으며, 2$\~$3일 마다 측정하였다. 결과 : 섬유육종세포에 베타카로틴 0.002, 0.02, 0.2, 2 mg/ml 농도액을 1시간 동안 접촉 후 얻은 각각 생존분율은 0.69$\pm$0.07, 0.59$\pm$0.08, 0.08$\pm$0.008 및 0.02$\pm$0.006이었다. 그리고 방사선조사 1시간 전 섬유육종세포에 베타카로틴 2mg/ml을 접촉한 후 조사량 2, 4, 6 및 8 Gy에서 얻은 각각의 생존분율은 0.13$\pm$0.05, 0.03$\pm$0.005, 0.01$\pm$0.002 및 0.009$\pm$0.0008이었으며 방사선조사 단독군의 경우 동일 조사량에서 얻은 생존분율은 각각 0.66$\pm$0.05, 0.40$\pm$0.04, 0.11$\pm$0.01 및 0.03$\pm$0.006으로 나타났다(P<0.05). 종양성장의 지연정도를 나타내는 실험에서 섬유육종을 쥐에 접종한 후 종양의 용적이 1,000 mm$^{}$ 에 달하는 기간은 베타카로틴 병용군과 방사선조사 단독군에서 각각 18일과 19일로 나타났다(p>0.05). 결론 :쥐 섬유육종세포에 베타카로틴을 접촉한 경우 세포독성이 나타났으며, 베타카로틴 농도 증가에 따라 세포 독성도 증가하였다. 그리고 쥐 섬유육종세포의 세포독성은 베타카로틴 병용군에서 방사선조사 단독군의 경우 보다 부가적으로 증가하였으며, 두 군간에 통계학적으로 현저한 차이를 보였다. 그러나 쥐 섬유육종 성장 지연정도에 있어서 베타카로틴 병용군과 방사선조사 단독군간의 통계학적으로 뚜렷한 차이는 없었다.

• 한국세라믹학회지
• /
• 제21권4호
• /
• pp.373-381
• /
• 1984

The coloration of the $Nd_2O_3$ contained $R_2O-BaO-SrO-ZrO_2-SiO_2$ glass added the various amount of $CeO_2$ $MnO_2$, $Fe_2O_3$ and $As_2O_3$ alone or together by the irradiation of X-ray irradiation,. The glasses added $CeO_2$ in proportion to amount were more effective on preventing coloration by X-ray irradiation but the addition of $MnO_2$ produced different color according to the amount of addition. The addition of the $Fe_2O_3$, $TiO_2$ and $As_2O_3$ did not give much effects to the transmission changes of $Nd_2O_3$ contained glass by X-ray irradiation but the glass added $CeO_2$ , $Fe_2O_3$, $TiO_2$ together was most effective to prevent coloration and transmisson changes.

• 대한의생명과학회지
• /
• 제12권4호
• /
• pp.427-433
• /
• 2006

We investigated the effect of propolis on the activity of antioxidant enzymes in rat liver exposed by X-ray irradiation. The dosage of propolis showed the effect of lowering the concentration of superoxide anion in irradiated rat liver, suggesting that propolis has a significant role to remove superoxide anion as an antioxidant and/or by activating the antioxidant enzyme. The activities of superoxide dismutase (SOD) and glutathione reductase (GR), disturbed by X-ray irradiation, were restored in 30 days to normal status in the group which dosed propolis before X-ray irradiation. Interestingly, catalase (CAT) and glutathione peroxidase (GPOX) activities were highly increased with feeding propolis to rat compared to untreated group, whereas glutathione s-transferase (GST) activity was little affected. Taken together, it suggests that the propolis has a protective role in the rat liver cells against X-ray irradiation by increasing and recovering the activities of antioxidant enzymes.