• Korean Journal of Veterinary Research
• /
• v.44 no.3
• /
• pp.323-327
• /
• 2004

The purpose of the present experiment was to investigate the micronuclei(MN) frequency in cytokinesis-blocked(CB) cells after various doses of gamma-rays in pig (Landrace, male, 3-month-old) and so to contribute to the clarification of the question whether these species are suitable as a target organism in the test system. The frequencies of binucleated cells, and gamma-ray-induced MN in CB cells at several doses were measured in three donors. The peaks of binucleated lymphocyte formation(22%) were found at a concentration of 2% phytohaemagglutinin(PHA) and $4{\mu}g/ml$ Cytochalasin B(Cyt-B) in pig at 72 hours after incubation. Measurements performed after irradiation showed a dose-related increases in MN frequency in each of the donors studied. When analysed by linear-quadratic model the line of best fit was $y=0.0183D+0.0124D^2+0.0133$(y = number of MN/CB cells and D=irradiation dose in Gy). In conclusion, the results demonstrate that it appears feasible to use pig as target organisms in the micronucleus test to estimate the cytogenetic damage caused by ionizing radiations or, potentially, chemical compounds.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
• /
• 2003.10a
• /
• pp.152-152
• /
• 2003

As utilization of radiation in medicine, industry and biochemical research increases, the protection against radiation damage has become an important issue. Natural products such as herbal medicines are beginning to receive attention as modifiers on the radiation response. In the present study, the protective effect of a herb, Menthae Herba, against radiation-induced DNA damage was evaluated using alkaline single-cell gel electrophoresis (SCGE; comet assay) in the mouse peripheral blood Iymphocytes and the micronucleus formation test in the Chinese hamster ovary (CHO) cells. The tail moment, which was a marker of DNA damage in the SCGE, and the frequency of micronuclei was decreased in groups treated with Mentae Herba extract before exposure to 200 cGy of gamma-ray. We also confirmed its activities to scavenge DPPH and hydroxyl radicals. These experiments demonstrated that Menthae Herba was effective at reducing the radiation-induced damage of DNA and scavenging free radicals. It is plausible that scavenging of free radicals by Menthae Herba may have played an important role in providing the protection against the radiation-induced damage to the DNA. These results indicated that Menthae Herba might be a useful radioprotector and that radical scavenging appears to be one of the mechanisms of radiation protection.

• Korean journal of food and cookery science
• /
• v.16 no.6
• /
• pp.652-662
• /
• 2000

This study was performed to measure the mutagenicity of fish by cooking and storage. Mutagenicity of the fish extract was measured by Ames test(Salmonella typhimurium reversion assay with TA 100) in vitro and by micro-nucleus test in vivo. The fish samples screened in this study were white fish(Trichiurus, Croaker, Salted Croaker) and red fish(Saury pike, Mackerel, Yellowtail, Salmon). The number of revertants of red fish were significantly higher than that of white fish. And the mutagenicity of mackerel was higher than other red fish, so followed experiment was made by using the extract of mackerel. Mutagenicity of the samples cooked on microwave oven was the lowest, whereas there was no significant difference between the samples cooked on gas grill and the ones on electric grill. In the presence of S9 mixture, the methanol extract of mackerel showed 2∼4 times high values of mutagenicity in comparison with the extract without S9. The extract of mackerel cooked with various vegetable juices showed inhibitory effects on the mutagenicity in the order of green tea, ginger, and radish. Also, the number of revertants was increased in the stored samples. Mutagenicity of the samples stored in the refrigerator was higher than that of the freezer. In micronucleus test, the methanol extract treated with vegetable juice inhibited micro-nucleus formation in bone marrow by cyclophosphamide in the order of ginger, green tea, and radish. In TBA test, there was a tendency that TBA values were increased as the storage time increased. Also, the rancidity of sample were stored in the refrigerator was higher value than sample stored in the freezer. Samples cooked on microwave oven showed the highest value in rancidity. When the antioxidant effect of vegetable juice was measured by electron donating ability(EDA) of mackerel cooked with vegetable juice to DPPH, the samples treated with onion showed the highest value of EDA(%), and the samples treated with green tea, ginger and cabbage also showed the antioxidant effect.

• Journal of Food Hygiene and Safety
• /
• v.21 no.2
• /
• pp.107-112
• /
• 2006

Guh Sung Y.L.S-95 (GS95) is a kind of polyacidic solution, which contains acetic acid as a main component. We investigated in the present study tile genetic toxicity of GS95 according to the standard operation procedure from Korean Institute of Toxicology. In the Salmonella typhimurium reverse mutation assay using TA1535, TA1537, TA98 and TA100, GS95 did not induce mutation up to $5,000{\mu}g/plate$. GS95 did not induce chromosome aberration in Chinese hamster lung fibroblast in the concentration range between 1.25 and 5 mg/mL. In the rodent micronucleus assay, the frequency of micronucleated polychromatic erythrocyte in GS95 treated mice were not increased up to 5,000 mg/kg compared to the vehicle treated mice. Taken all these data together, GS95 was proven to be nongenotoxic in the concentration ranges tested.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.3
• /
• pp.1119-1123
• /
• 2014

Head and neck cancers (HNC) are extremely complex disease types and it is likely that chromosomal instability is involved in the genetic mechanisms of its genesis. However, there is little information regarding the background levels of chromosome instability in these patients. In this pilot study, we examined spontaneous chromosome instability in short-term lymphocyte cultures (72 hours) from 72 study subjects - 36 newly diagnosed HNC squamous cell carcinoma patients and 36 healthy ethnic controls. We estimated chromosome instability (CIN) using chromosomal aberration (CA) analysis and nuclear level anomalies using the Cytokinesis Block Micronucleus Cytome Assay (CBMN Cyt Assay). The proliferation rates in cultures of peripheral blood lymphocytes (PBL) were assessed by calculating the Cytokinesis Block Proliferation Index (CBPI). Our results showed a significantly higher mean level of spontaneous chromosome type aberrations (CSAs), chromatid type aberration (CTAs) dicentric chromosomes (DIC) and chromosome aneuploidy (CANE UP) in patients (CSAs, $0.0294{\pm}0.0038$; CTAs, $0.0925{\pm}0.0060$; DICs, $0.0213{\pm}0.0003$; and CANE UPs, $0.0308{\pm}0.0035$) compared to controls (CSAs, $0.0005{\pm}0.0003$; CTAs, $0.0058{\pm}0.0015$; DICs, $0.0005{\pm}0.0003$; and CANEUPs, $0.0052{\pm}0.0013$) where p<0.001l. Similarly, spontaneous nuclear anomalies showed significantly higher mean level of micronuclei (MNi), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) among cases (MNi, $0.01867{\pm}0.00108$; NPBs, $0.0156{\pm}0.00234$; NBUDs, $0.00658{\pm}0.00068$) compared with controls (MNi, $0.00027{\pm}0.00009$; NPBs, $0.00002{\pm}0.00002$; NBUDs, $0.00011{\pm}0.00007$).The evaluation of CBPI supported genomic instability in the peripheral blood lymphocytes showing a significantly lower proliferation rate in HNC patients ($1.525{\pm}0.005552$) compared to healthy subjects ($1.686{\pm}0.009520$) (p<0.0001). In conclusion, our preliminary results showed that visible spontaneous genomic instability and low rate proliferation in the cultured peripheral lymphocytes of solid tumors could be biomarkers to predict malignancy in early stages.

• Toxicological Research
• /
• v.29 no.4
• /
• pp.263-278
• /
• 2013

The silkworm extract powder contain 1-deoxynojirimycin (DNJ), a potent ${\alpha}$-glycosidase inhibitor, has therapeutic potency against diabetes mellitus. Therefore, natural products containing DNJ from mulberry leaves and silkworm are consumed as health functional food. The present study was performed to evaluate the safety of the silkworm extract powder, a health food which containing the DNJ. The repeated toxicity studies and gentic toxicity studies of the silkworm extract powder were performed to obtain the data for new functional food approval in MFDS. The safety was evaluated by a single-dose oral toxicity study and a 90 day repeated-dose oral toxicity study in Sprague-Dawley rats. The silkworm extract powder was also evaluated for its mutagenic potential in a battery of genetic toxicity test: in vitro bacterial reverse mutation assay, in vitro chromosomal aberration test, and in vivo mouse bone marrow micronucleus assay. The results of the genetic toxicology assays were negative in all of the assays. The approximate lethal dose in single oral dose toxicity study was considered to be higher than 5000 mg/kg in rats. In the 90 day study, the dose levels were wet at 0, 500, 1000, 2000 mg/kg/day, and 10 animals/sex/dose were treated with oral gavage. The parameters that were monitored were clinical signs, body weights, food and water consumptions, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, organ weights, and histopathological examination. No adverse effects were observed after the 90 day administration of the silkworm extract powder. The No-Observed-Adverse-Effect-Level (NOAEL) of silkworm extract powder in the 90 day study was 2000 mg/kg/day in both sexes, and no target organ was identified.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.5
• /
• pp.921-927
• /
• 2001

This study was performed to investigated the effects on the cytotoxicity and antigenotoxicity of Cordyceps militaris extracts on the human cancer cell lines. The ethanol extract and five fractions which were hexane, chloroform, ethylacetate, butanol and aqueous were screened for crytotoxicity on human lung carcinoma(A549). human breast adenocarcinoma (MCF-7) human epitheloid carcinoma(HeLa), human fibrosarcoma(HT1080) human hepatocellular carcinoma(Hep3B), human gastric carcinoma(KATOIII) and chronic myelogenous leukemia(K562) cell by SRB and MTT assays. The results showed that growth inhibition rates of the human cancer cell in the presence of Cordyceps militaris were inhibited with increasing concentration of the extract. The ethanol extract from Cordyceps militaris had strong inhibitory effects in1 mg/mL treatment by SRB assay , showing 89.4%, 85.7%, 72.9% and 65.5% inhibition in HT1080, HeLa, Hep3B and A549, respectively. The treatment of 1 mg/mL hexane fraction by SRB assay had the strongest cytotoxicity with 97.0% on HT1080 followed by MCF-7(92.9%) and HeLA(90.3%). The inhibition ration on KATOIII by MTT assay was much higher in the butanol (83.7%) and aqueous (80.4%) than in the ethanol extract (61.5%) And also, K562 showed similar tendency with KATOIII. The effects of Cordyceps militaris extracts on the frequencies of micronucleated polychromatic erythrocytes (MNPCEs) induced by N-methyl-N-nitro-N-nitrosoguanidime(MNNG) were investigated in the bone-marrow cells of ICR male mice. The amount of 10, 20, 40 and 80 mg/kg of each extract were administered to animals immediately after injection of MNNG, and the exposure time was 36 hours. Significant reductions(p<0.05) with 39.7%, 52.7%, 71.4% and 83.9% were observed in the frequencies of MNPCE when 10, 20, 40 and 80 mg/kg of the hexane fraction of Coryceps militarus extracts were given to the mice.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.37 no.5
• /
• pp.415-420
• /
• 2011

Purpose: Calcium phosphate cement (CPC) is one of many useful materials for restoring tooth defects, periodontium and maxillofacial area. Chitosan is a biodegradable material that has been shown to promote the growth and differentiation of osteoblasts in culture. This study examined the interaction between odontoblasts and bio-calcium phosphate cement reinforced with chitosan. Materials and Methods: $5{\times}10^3$ odontoblastic cells were seeded into each well. Various concentrations of bio-calcium phosphate cement reinforced with chitosan (10, 20, 50, 100, 200, 500 ${\mu}g$/ml, 1, 2, 4 mg/ml) were diluted and added to the wells. The well was incubated for 24 h, 48 h and 72 h. After incubation, the number of cells was assessed to determine the cell viability. A cytokinesis-block micronucleus assay and chromosomal aberration test were carried out to estimate the extent of chromosomal abnormalities. Microscopic photographs and RT-PCR were performed to examine the adhesion potential of bio-calcium phosphate cement reinforced with chitosan. Results: Bio-CPC-reinforced chitosan did not show significant cytotoxicity. The number of damaged chromosomes in the cells treated with Bio-CPC-reinforced chitosan was similar to that in the control cells. There was no significant increase in the number of chromosomal aberrations in the Bio-CPC reinforced chitosan exposed cells. Microscopic photographs and RT-PCR confirmed the adhesive potential of bio-CPC reinforced chitosan to odontoblasts. Conclusion: Bio-CPC-reinforced chitosan did not affect the odontoblastic cell viability, and had no significant cytotoxic effect. Bio-CPC-reinforced chitosan showed adhesive potential to odontoblasts. These results are expected form the basis of future studies on the effectiveness of dental restorative materials in Bio-CPC reinforced with chitosan.

• Toxicological Research
• /
• v.20 no.4
• /
• pp.365-374
• /
• 2004

Inhalation toxicity, mutagenicity, and immunotoxicity tests were performed using a smoke generation system to investigate the safety of Herbrette, a tobacco substitute made with the leaves of Perilla frutescens. ICR mice were exposed to nicotine-free Herbrette smoke with concentrations of 0 (control), 4.08 $\pm$ 1.32 mg/$m^3$ (low dose), 7.72 $\pm$ 2.14 mg/$m^3$ (medium dose) and 12.83 $\pm$ 1.69 mg/$m^3$ (high dose) total particulate matters (TPM) for 4 weeks. When compared to the control group, the body weights, organ weights in the exposed groups did not show any significant differences. However, certain change of several serum chemical data and biochemical parameters were observed, however, the changes were within normal physiological ranges. Moreover, no changes in organ weight, and no gross/microscopic changes were observed between the exposed and control groups. Salmonella typhimurium reverse mutation, in vivo chromosomal aberration and micronucleus assays revealed that Herbrette did not induce mutagenicity. Upon evaluation of peripheral cellular immunity of mice through in vitro lymphocyte proliferation assay, no significant difference was observed in mean stimulation index between the exposed and control groups. Taken together, our results strongly suggest that Herbrette may not cause toxicity on mice under current condition.

• Journal of Environmental Health Sciences
• /
• v.37 no.6
• /
• pp.429-439
• /
• 2011

Objectives: Ethylene oxide (EtO) is classified as a human carcinogen, but EtO is still widely used to sterilize heat-sensitive materials in hospitals. Employees working around sterilizers are exposed to EtO after sterilization. The aim of the present study was to assess the exposure of EtO level, coupled with occupationally induced micronuclei from hospital workers. The influence of genetic polymorphisms of detoxifying genes (GSTT1 and GSTM1) and DNA repair genes (XRCC1 and XRCC3) on the frequencies of micronuclei in relation to exposure of EtO was also investigated. Methods: The study population was composed of 35 occupationally exposed workers to EtO, 18 student controls and 44 unexposed hospital controls in Korea. Exposure to EtO is measured by passive personal samplers. We analyzed the frequencies of micronuclei by performing cytokinesis-block micronucleus assay (CBMN assay) and GSTM1, GSTT1, XRCC1, and XRCC3 were also genotyped by performing polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: The frequencies of micronuclei in EtO exposure group, student controls and hospital controls were $18.00{\pm}7.73$, $10.47{\pm}7.96$ and $13.86{\pm}6.35$ respectively and their differences were statistically significant, but no significant differences according to the level of EtO were observed. There was a dose-response relationship between the frequencies of micronuclei and cumulative dose of EtO, but no significantly differences were observed. We also investigated the influence of genetic polymorphisms (GSTM1, GSTT1, XRCC1, and XRCC3) on the frequencies of micronuclei, but there were no differences in the frequencies of micronuclei by genetic polymorphisms. Conclusions: The frequencies of micronuclei in EtO exposure group was significantly higher than control groups. A dose-response relationship was found between the level of EtO exposure and the frequencies of micronuclei, but no statistically differences were observed. We also found that the frequencies of micronuclei were increased according to cumulative EtO level. There was no association of the genetic GSTM1, GSTT1, XRCC1, and XRCC3 state with the frequency of micronuclei induced by EtO exposure.