• Journal of Radiation Protection and Research
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• 제41권3호
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• pp.206-210
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• 2016

Background: Ionizing radiation causes cellular damage and death through the direct damage and/or indirectly the production of ROS, which induces oxidative stress. This study was designed to evaluate the in vivo radioprotective effects of a bio-active material coated fabric (BMCF) against ${\gamma}$-irradiation-induced cellular damage in Sprague-Dawley (SD) rats. Materials and Methods: Healthy male SD rats wore bio-active material coated (concentrations in 10% and 30%) fabric for 7 days after 3 Gy of ${\gamma}$-irradiation. Radioprotective effects were evaluated by performing various biochemical assays including spleen and thymus index, WBC count, hepatic damage marker enzymes [aspartate transaminase (AST) and alanine transaminase (ALT)] in plasma, liver antioxidant enzymes, and mitochondrial activity in muscle. Results and Discussions: Exposure to ${\gamma}$-irradiation resulted in hepatocellular and immune systemic damage. Gamma-irradiation induced decreases in antioxidant enzymes. However, wearing the BMCF-30% decreased significantly AST and ALT activities in plasma. Furthermore, wearing the BMCF-30% increased SOD (superoxide dismutase) and mitochondrial activity. Conclusion: These results suggest that wearing BMCF offers effective radioprotection against ${\gamma}$-irradiation-induced cellular damage in SD rats.

• 한국약용작물학회지
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• 제19권4호
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• pp.287-299
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• 2011

Pharmacological effects of Panax ginseng have been demonstrated in cardiovascular system, endocrine secretion and immune system, together with antitumor, anti-stress and anti-oxidant activities. Modern scientific data show protective effect of ginseng against bone marrow cell death, increased survival rate of experimental animals, recovery of hematopoietic injury, immunopotentiation, reduction of damaged intestinal epithelial cells, inhibition of mutagenesis and effective protection against testicular damages, caused by radiation exposure. And also, ginseng acts in indirect fashion to protect radical processes by inhibition of initiation of free radical processes and thus reduces the radiation damages. The research has made much progress, but still insufficient to fully uncover the action mechanism of ginseng components on the molecule level. This review provides the usefulness of natural product, showing no toxic effects, as an radioprotective agent. Furthermore, the further clinical trials on radioprotection of ginseng need to be highly done to clarify its scientific application. The effective components of ginseng has been known as ginsenosides. Considering that each of these ginsenosides has pharmacological effect, it seems likely that non-saponin components might have radioprotective effects superior to those of ginsenosides, suggesting its active ingredients to be non-saponin series. These results also show that the combined effects of saponin and non-saponin components play an important role in the radioprotective effects of ginseng.

• 대한수의학회지
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• 제56권1호
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• pp.29-35
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• 2016

When exposed to gamma-rays, hair follicular cells immediately go through apoptosis, which hampers their rapid differentiation essential for the regeneration of hair. Phloroglucinol (PG) is a phenolic compound of Ecklonia cava, brown algae abundant in Jeju island, Korea. Containing plentiful polyphenols, PG is known for its instructive effects by inhibiting apoptosis, scavenging oxygen radicals, and protecting cells against oxidative stress. In this study, we demonstrate that PG rescues radiosensitive hair follicular cells from gamma radiation-induced apoptosis and DNA damage. To identify protective capacity of PG on hair follicles, we irradiated with 8.5 Gy (1.5 Gy/min) of gamma-rays to the whole body of C57BL/6 mice at day 6 after depilation with or without PG. In mice exposed to radiation, the expression of proapoptotic molecule p53 was downregulated in the skin of PG treated group. On immunohistochemical observation of the skin, PG inhibited the immunoreactivity of p53 and cleaved caspase-3. PG treatment protected hair follicular cells from cell death due to gamma-radiation. Our results suggest that PG presents radioprotective effects by inhibiting apoptosis of radiosensitive hair follicular cells and can protect hair follicular cells from gamma-ray induced damage.

• Food Science and Biotechnology
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• 제17권4호
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• pp.718-722
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• 2008

Elaeocarpus sylvestris var. ellipticus (E.S.), which contains 1, 2, 3, 4, 6-penta-O-galloyl-beta-D-glucose (PGG), is reported to have the ability to scavenge oxygen radicals, thereby protecting rat neuronal cells from oxidative damage. The potential of an E.S. extract, which contains a rich PGG, to protect radiosensitive lymphocytes and intestinal crypt cells from radiation injury induced by a single whole-body irradiation (WBI) in vivo was investigated. Our results demonstrated that in immune cells, E.S. treatment decreased the percent of tail DNA, a parameter of DNA damage, compared with levels in untreated, irradiated controls. Furthermore, apoptosis was significantly decreased in lymphocytes and intestinal crypt cells of E.S.-treated mice compared with irradiated controls. These results suggest that the E.S. extract can strengthen the radioresistance of radiosensitive lymphocytes and crypt cells by preventing apoptosis. Therefore, it was concluded that E.S. extract has the radioprotective effects in vivo through an inhibition of apoptosis.

• Journal of Radiation Protection and Research
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• 제7권1호
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• pp.11-16
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• 1982

Cysteamine(Mercaptoethylamine, MEA), S-2-Aminoethyl isothionronium Bromide HBr(AET) 및 S-2(2-Aminoethyl) Dihydrogen phosphorothioate(WR-638)들을 합성(合成)하고 이들 각각(各各) 또는 그들의 혼합물(混合物)의 $^{60}Co$ ${\gamma}$-선(線) 방사선(放射線)에 대(對)한 장해방호효과(障害防護效果)를 ICR생쥐를 사용(使用)하여 검토(檢討)하였다. 조사전(照射前) 15분(分)에 복강내(腹腔內)에 약제(藥劑)를 투여(投與)하고 그 효과(效果)를 검토(檢討)한바 MEA, AET 및 그들 혼합물(混合物)에 있어서는 약독작용(藥毒作用)이 관찰(觀察)되었으나 WR-638 및 AET와의 혼합물(混合物)에서는 약독작용(藥毒作用)이 경미(輕微)하거나 또는 거의 없었다. 시험(試驗)한 각각(各各)의 화합물(化合物) 및 그 혼합물(混合物)들은 $^{60}Co$ $\gamma$-선(線) 방사선(放射線)에 대(對)한 방호효과(防護效果)를 나타냈으며 AET와 WR-638의 혼합물(混合物)에 있어서는 부가(附加)된 방사선(放射線) 방호효과(防護效果)가 관찰(觀察)되었다.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2002년도 학술대회지
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• pp.385-391
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• 2002

Panax ginseng (family- Araliaceae) is a native plant of Korea and has been used for past several years among oriental people. To evaluate the radioprotective potential of P. ginseng on the formation of giant cells in the testis of Swiss albino mice, the animals were divided into four groups: -(I)-Only vehicle was administered. (II)P. ginseng treated group: -The animals received 10 mg/kg body weight P. ginseng root extract (in DDW) i.p. continuously for 30 days. (III) Irradiated group: -The animals were exposed to 8 Gy gamma radiation at the dose rate of 1.69 Gy/min at the distance of 80 ems. (IV) Combined treatment group: -Animals were given P. ginseng extract for four days and on fourth day they were irradiated to 8 Gy gamma radiation after 30 minute of extract administration. The animals of these three groups were autopsied on day 1,3, 7, 14 and 30 days. In ginseng treated group, active spermatogenesis was observed without any toxic effect. Histopathological studies of irradiated group (II) revealed reduction in germ cell count, loss of sperms and formation of multinucleated giant cells on day 7th. These giant cells were formed by round nuclei of early or late spermatids. In combination group (III), although germinal epithelium was still disorganized with loss of cells in few tubules, but no giant cell formation was observed. In order to know the mechanism of radioprotection of ginseng, LPO and GSH were estimated. It was observed that pretreated irradiated animals showed inhibition of LPO and increase in GSH. Thus the present study suggests ginseng protects male gonads. This may be attributed to the inhibition of LPO and increase synthesis of GSH byginseng.

• Archives of Pharmacal Research
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• 제22권2호
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• pp.99-107
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• 1999

A series of organosulfur compounds were synthesized with the aim of developing chemopreventive compounds active against hepatotoxicity and chemical carcinogesis. 2-(Allylthio) prazine (2-AP) was effective in inhibiting cytochrome P450 2E1-mediated catalytic activities and protein expression, and in inducing microsomal epoxide hydrolase and major glutathione S-transferases. 2-AP reduced the hepatotoxicity caused by toxicant sand elevated cellular GSH content. Development of skin tumors, pulmonary adenoma and aberrant crypt foci in colon by various chemical carcinogens was inhibited by 2-AP pretreatment. Anticarcinogenic effects of 2-AP at the stage of initiation of tumors were also observed in the aflatoxin B1 ($AFB_1$)-induced three-step medium-term hepatocarcinogenesis model. Reduction of $AFB_1$-DNA adduct by 2-AP appeared to result from the decreased formation of $AFB_1$-8,9-epoxide via suppression of cytochrome P450, while induction of GST 2-AP increases the excretion of glutathione-conjugated $AFB_1$ . 2-AP was a radioprotective agent effective against the lethal dose of total body irradiation and reduced radiation-induced injury in association with the elevation of detoxifying gene expression. 2-AP produces reactive oxygen species in vivo, which is not mediated with the thiol-dependent production of oxidants and that NF-KB activation is not involved in the induction of the detoxifying enzymes. the mechanism of chemoprotection by 2-AP may involve inhibition of the P450-mediated metabolic activation of chemical carcinogens and enhancement of electrophilic detoxification through induction of phase II detoxification enzymes which would facilitate the clearance of activated metabolites through conjugation reaction.

• Imaging Science in Dentistry
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• 제53권1호
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• pp.69-75
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• 2023

Purpose: Maxillofacial trauma predominantly affects young adults between 20 and 40 years of age. Although radioprotection is a legal requirement, the significant potential of dose reduction in computed tomography (CT) is still underused in the clinical routine. The objective of this study was to evaluate whether maxillofacial fractures can be reliably detected and classified using ultra-low-dose CT. Materials and Methods: CT images of 123 clinical cases with maxillofacial fractures were classified by two readers using the AOCOIAC software and compared with the corresponding results from post-treatment images. In group 1, consisting of 97 patients with isolated facial trauma, pre-treatment CT images at different dose levels (volumetric computed tomography dose index: ultra-low dose, 2.6 mGy; low dose, <10 mGy; and regular dose, <20 mGy) were compared with post-treatment cone-beam computed tomography (CBCT). In group 2, consisting of 31 patients with complex midface fractures, pre-treatment shock room CT images were compared with post-treatment CT at different dose levels or CBCT. All images were presented in random order and classified by 2 readers blinded to the clinical results. All cases with an unequal classification were re-evaluated. Results: In both groups, ultra-low-dose CT had no clinically relevant effect on fracture classification. Fourteen cases in group 2 showed minor differences in the classification code, which were no longer obvious after comparing the images directly to each other. Conclusion: Ultra-low-dose CT images allowed the correct diagnosis and classification of maxillofacial fractures. These results might lead to a substantial reconsideration of current reference dose levels.

• Journal of Radiation Protection and Research
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• 제48권2호
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• pp.84-89
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• 2023

Background: Food consumption is one of the most important routes for radionuclide intake for the public; therefore, there is the need to have a comprehensive understanding of the amount of radioactivity in food products. Consumption of radionuclide-contaminated food could increase potential health risks associated with exposure to radiation such as cancers. The present study aims to determine radioactivity levels in some food products (milk, rice, sugar, and wheat flour) consumed in Mali and to evaluate the radiological effect on the public health from these radionuclides. Materials and Methods: The health impact due to ingestion of radionuclides from these foods was evaluated by the determination of activity concentration of radionuclides ²³⁸U, ²³²Th, ⁴⁰K, and ¹³⁷Cs using gamma spectrometry system with high-purity germanium detector and radiological hazards index in 16 samples collected in some markets, mall, and shops of Bamako-Mali. Results and Discussion: The average activity concentrations were 9.8±0.6 Bq/kg for ²³⁸U, 8.7±0.5 Bq/kg for ²³²Th, 162.9±7.9 Bq/kg for ⁴⁰K, and 0.0035±0.0005 Bq/kg for ¹³⁷Cs. The mean values of radiological hazard parameters such as annual committed effective dose, internal hazard index, and risk assessment from this work were within the dose criteria limits given by international organizations (International Commission on Radiological Protection and United Nations Scientific Committee on the Effects of Atomic Radiation) and national standards. Conclusion: The results show low public exposure to radioactivity and associated radiological impact on public health. Nevertheless, this study stipulates vital data for future research and regulatory authorities in Mali.

• Journal of Radiation Protection and Research
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• 제47권4호
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• pp.181-194
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• 2022

Internal dosimetry is a discipline which brings together a set of knowledge, tools and procedures for calculating the dose received after incorporation of radionuclides into the body. Several steps are necessary to calculate the committed effective dose (CED) for workers or members of the public. Each step uses the best available knowledge in the field of radionuclide biokinetics, energy deposition in organs and tissues, the efficiency of radiation to cause a stochastic effect, or in the contributions of individual organs and tissues to overall detriment from radiation. In all these fields, knowledge is abundant and supported by many works initiated several decades ago. That makes the CED a very robust quantity, representing exposure for reference persons in reference situation of exposure and to be used for optimization and assessment of compliance with dose limits. However, the CED suffers from certain limitations, accepted by the International Commission on Radiological Protection (ICRP) for reasons of simplification. Some of its limitations deserve to be overcome and the ICRP is continuously working on this. Beyond the efforts to make the CED an even more reliable and precise tool, there is an increasing demand for personalized dosimetry, particularly in the medical field. To respond to this demand, currently available tools in dosimetry can be adjusted. However, this would require coupling these efforts with a better assessment of the individual risk, which would then have to consider the physiology of the persons concerned but also their lifestyle and medical history. Dosimetry and risk assessment are closely linked and can only be developed in parallel. This paper presents the state of the art of internal dosimetry knowledge and the limitations to be overcome both to make the CED more precise and to develop other dosimetric quantities, which would make it possible to better approximate the individual dose.