• Title/Summary/Keyword: Low Dose

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Studies on the anti-infiammatiry activity and its mechanism of daidzein (Daidzein의 항염작용과 그 작용기전에 관한 연구 (II))

  • 허인회;이상준;김형춘
    • YAKHAK HOEJI
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    • v.31 no.3
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    • pp.164-172
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    • 1987
  • The anti-inflammatory mechanism of daidzein was investigated in rats and mice. Daidzein and 4'-methyldaidzein inhibited capillary permeability and lipid peroxidation. Daidzein inhibited growth of granuloma when it was administered into the carrageenin pouch at the low dose, while it acted contrarily at the high dose. Daidzein decreased the antiinflammatory effect in adrenalectomized rat, depleted ascorbic acid and cholesterol contents in adrenals, and increased corticosterone level in plasma, suggesting dadzein acts on the hypophysisadrenal system.

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Review of Clinical Cancer Research Methodology of Botanical Agents (한약 및 천연물의 항암 임상연구 방법론에 대한 고찰)

  • Oh, Hye Kyung;Lee, Jee Young;Ryu, Han Sung;Yoon, Seong Woo
    • Journal of Korean Traditional Oncology
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    • v.20 no.1
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    • pp.11-21
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    • 2015
  • Objectives : The cancer incidence and cancer burden is increasing. In addition, the use of botanical agents in cancer care is increasing. This article aims to review a research strategy for botanical agents. Methods : The clinical studies of anticancer botanical agents and the papers about clinical research methodology of botanical agents were reviewed. Results : In phase I study, safety confirmation, optimal dose determination and drug interaction study are important. Most botanical agents have low toxicity and some have non-monotone dose response. Therefore, dose-response curve must be evaluated separately from the dose-toxicity curve to determine optimal dose. Although anticancer botanical agents can't shrink tumor size rapidly, they do extend survival. So, in phase II study, response should be evaluated by the survival. Conclusions : Clinical research of botanical agents in cancer is different from traditional methods and strategies. Considering the characteristics of botanical agents and experimental mechanism is necessary in conducting botanical based clinical trials.

Safety classification for frequently-used herbal medicines inducing toxic metabolites (독성대사체를 생성하는 다빈도사용 한약재의 안전성등급화 - 천궁, 당귀, 감초, 숙지황을 중심으로 -)

  • Park, Yeong-Chul;Lee, Sundong
    • Journal of Society of Preventive Korean Medicine
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    • v.19 no.2
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    • pp.123-133
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    • 2015
  • The new formular for herbal medicine-safety classification in terms of evidence-based medicine was developed and applied to evaluate various herbal medicines in the previous study. This study is aimed to evaluate the frequently-used herbal medicines inducing toxic metabolites or reactive intermediates(RI), such as Ligusticum wallichii Franch, Angelica sinensis, Glycyrrhizae Radix, Rehmanniae Radix, based on 6 safety grades calculated from human equivalent dose(HED)-based MOS(margin of safety). HED-based MOS can be explained as the ratio of theoretical ALD(approximate lethal dose) of human as $LD_1$(lethal dose of 1%)/ clinical maximum dose as $ED_{99}$(Effective dose of 99%). The herbal medicine showing the ratio less than 1 belongs to Class 1, but the herbal medicine showing the ratio more than 500 belongs to Class 6 with the lowest toxicity. As a result, they were evaluated as class 2 for Angelica sinensis and Glycyrrhizae Radix, class 3 for Ligusticum wallichii Franch and Rehmanniae Radix. These resultant grades for 4 herbal medicines were lower than the grade expected under consideration that these herbal medicines are used very frequently in oriental clinics. These low grades would be due to their ingredients which is biotransformed to toxic metabolites.

Maternal caffeine consumption has irreversible effects on reproductive parameters and fertility in male offspring rats

  • Dorostghoal, Mehran;Majd, Naeem Erfani;Nooraei, Parvaneh
    • Clinical and Experimental Reproductive Medicine
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    • v.39 no.4
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    • pp.144-152
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    • 2012
  • Objective: Concerns are growing about the decrease in male reproductive health. Caffeine is one of the popular nutrients that has been implicated as a risk factor for infertility. In the present study, we examined whether in utero and lactational exposure to caffeine affects the reproductive function of the offspring of rats. Methods: Pregnant rats received caffeine via drinking water during gestation (26 and 45 mg/kg) and lactation (25 and 35 mg/kg). Body and reproductive organ weight, seminiferous tubule diameter, germinal epithelium height, sperm parameters, fertility rate, number of implantations, and testosterone level of the offspring were assessed from birth to adulthood. Results: Significant dose-related decreases were observed in the body and reproductive organ weight, seminiferous tubule diameter, and germinal epithelium height of the offspring. Sperm density had declined significantly in offspring of the low-dose and high-dose groups, by 8.81% and 19.97%, respectively, by postnatal day 150. The number of viable fetuses had decreased significantly in females mated with male offspring of the high-dose group at postnatal days 60, 90, 120, and 150. There were also significant reductions in testosterone levels of high-dose group offspring from birth to postnatal day 150. Conclusion: It is concluded that maternal caffeine consumption impairs gonadal development and has long-term adverse effects on the reproductive efficiency of male offspring rats.

THE ANALYSIS ON SPACE RADIATION ENVIRONMENT AND EFFECT OF THE KOMPSAT-2 SPACECRAFT(I): TOTAL IONIZING DOSE EFFECT (아리랑 2호의 방사능 환경 및 영향에 관한 분석(I)- TOTAL IONIZING DOSE 영향 중심으로 -)

  • 백명진;김학정
    • Journal of Astronomy and Space Sciences
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    • v.18 no.2
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    • pp.153-162
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    • 2001
  • In this paper, space radiation environment and total ionizing dose(TID) effect have been analyzed for the KOMPSAT-2 operational orbit. It has been revealed that the trapped protons are concentrated in the SAA(South Atlantic Anomaly) area and that the trapped protons and electrons, and solar protons are main factors affecting TID. It turned out that low energy Particles can be effectively blocked by aluminum shielding thickness, but high energy Particles can not be effectively blocked by increasing aluminum shielding thickness. KOMPSAT-2 total radiation dose which is accumulated continuously to spacecraft electronics has been expressed as the function of aluminum thickness. These values ran be used as the criteria for the selection of electronic parts and shielding thinkness of the KOMPSAT-2 structure or electronic box.

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Storge Stability of Barleys Irradiated by Gamma-Ray (감마선 조사에 보리의 저장 안전성)

  • 김미라;손인숙
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.5
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    • pp.1076-1081
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    • 1999
  • Physicochemical, microbiological, and sensory properties of barleys irradiated by gamma ray at 1.2kGy, 10.1kGy, or 30.5kGy were investigated every 40 days during the storage at 25℃ and 50% relative humidity. Moisture content of the irradiated barleys decreased but crude lipid content increased during the storage. TBA values increased in proportion to the irradiation dose and to the storage period. In Hunter's color, L, a, and b values of 30.5kGy dose irradiated barleys were higher than those of the non irradiated barleys right after irradiation and this trend continued during the storage. Numbers of mesophilic and psychrophilic bacteria in the non irradiated barleys and 1.2kGy dose irradiated barleys were higher than those in the barleys irradiated at 10.1kGy and 30.5kGy during the storage. Numbers of yeasts and molds in the irradiated and non irradiated barleys were low and they did not greatly increase during the storage. In sensory evaluation, acidic odor of the barleys was strong at the 10.1kGy and 30.5 kGy dose irradiation but barley odor and humid odor were not significantly different among the groups depending upon the radiation dose and storage period.

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Effects of Low-Dose Gamma Irradiation on Physicochemical Properties and Formation of Resistant Starch of Corn Starch (저선량 감마선 조사가 옥수수 녹말의 이화학 성질 및 저항전분 생성에 미치는 영향)

  • Kim, Sung-Kon;Kim, Jeong-Hee;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
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    • v.38 no.3
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    • pp.378-384
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    • 2006
  • Intrinsic viscosity of starch irradiated with Co-60 (0.25-9.1 kGy) significantly decreased, and swelling power and solubility measured at $80^{\circ}C$ linearly increased with increasing irradiated dose. Radiation treatment up to 1 kGy increased amylose content of starch. Water-binding capacity increased rapidly up to 3 kGy. Peak viscosity of irradiated starches by Rapid visco Analyser and Visco/amylo/Graph indicated that the decrease in peak viscosity was dose-dependent. Gamma irradiation showed no effect on endothermic temperatures of irradiated starches, but decreased endothermic enthalpy with increasing dose level. Viscosity of starch autoclaved at $120^{\circ}C$ and air-dried significantly decreased with increasing irradiation dose. Resistant starch content slightly decreased upon irradiation.

Phototoxicity studies of LB20304a (LB20304a의 광독성시험)

  • Kim, Bae-Hwan;Lee, Sang-Koo;Yoon, Byong-Ill
    • Korean Journal of Veterinary Pathology
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    • v.1 no.1
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    • pp.40-45
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    • 1997
  • The phototoxic potentials of LB20304a a new quinolone compound being developed by LG Chemical Ltd, and reference compounds (Ciprofloxacin; CPFX, Enoxacin; ENX and Lomefloxacin; LFLX) were compared in a murine model. in addition photostability of these compunds was studied after irradiation with long-wave UV light(UVA, 0, 0.3 1 or 3 Joule/$Cm^2$) When hairless mice(9 to 11 weeks old 19-26g) were orally administered with different dose levels of test compunds and exposed to UVA(40J/$cm^2$) inflammatory reactions were observed in a dose dependent manner. Among the compounds tested, LB20304a demonstrated the least phototoxic effects and showed no inflammatroy lesions at a dose level of 100mg.kg (Low dose). ENX and LFLX demonstrated much greater phototoxic reactions while CPFX showed similar or slightly greater phototoxic reactions compared to LB20304a. Similar to the in-vivo results the solutions of LB20304a and CPFX irradiated with UVA demonstrated reduced spectral changes compared to those of ENX and LFLX. In conclusion these data suggest that phototoxic potencies of the quinolones tested were; LFLX > ENX > CPFX $\geq$ LB20304a. No phototoxic dose of LB20304a in mice was 100 mg/kg.

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Safety Assessment of Nuclear Waste Incineration Process by Estimating Radiation Dose of Workers and Residential Individuals (원자력폐기물 소각공정에서의 작업자 및 인근주민의 피폭선량에 따른 안전성 평가)

  • 서용칠
    • Journal of the Korean Society of Safety
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    • v.8 no.4
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    • pp.165-174
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    • 1993
  • For the safety assessment of the demonstration-scale incineration plant for treating the combustible radioactive wastes, radiation doses of a worker and a residential individual were estimated. The demonstration plant showed a good performance of trial-burn tests using non-radioactive tracers with resulting In high mass reduction of around 40 times and very low emmission of dusts through a stack, which promised a high decontamination factor in an order of 10$^{7}$ . Based on the result s obtained from the trial-burns in the process, the estimation of radiation dose for workers and general publics near the plant was made using dose pathway calculation theories. The parametric values for calculation were selected from design and operational results of the process and from more conservative conditions In reference data. The estimated annual doses for workers and residential indivisuals were 3.07 $\times$ 10$^{-4}$ and 4.35 X 10$^{-8}$ $\mu$Sv/y, respectively, which were high enough to operate the process when comparing with the allowable dose limit in the regulation. The dose calculation models were quite applicable with showing an excellent safety for the process.

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Preliminary Evaluation of Radiological Impact for Domestic On-road Transportation of Decommissioning Waste of Kori Unit 1

  • Dho, Ho-Seog;Seo, Myung-Hwan;Kim, Rin-Ah;Kim, Tae-Man;Cho, Chun-Hyung
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.4
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    • pp.537-548
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    • 2020
  • Currently, radioactive waste for disposal has been restricted to low and intermediate level radioactive waste generated during operation of nuclear power plants, and these radioactive wastes were managed and disposed of the 200 L and 320 L of steel drums. However, it is expected that it will be difficult to manage a large amount of decommissioning waste of the Kori unit 1 with the existing drums and transportation containers. Accordingly, the KORAD is currently developing various and large-sized containers for packaging, transportation, and disposal of decommissioning waste. In this study, the radiation exposure doses of workers and the public were evaluated using RADTRAN computational analysis code in case of the domestic on-road transportation of new package and transportation containers under development. The results were compared with the domestic annual dose limit. In addition, the sensitivity of the expected exposure dose according to the change in the leakage rate of radionuclides in the waste packaging was evaluated. As a result of the evaluation, it was confirmed that the exposure dose under normal and accident condition was less than the domestic annual exposure dose limit. However, in the case of a number of loading and unloading operations, working systems should be prepared to reduce the exposure of workers.