• 환경생물
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• 제31권3호
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• pp.189-191
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• 2013

Mycotoxins such as aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEA) are widespread contaminants of food and feedstuffs. It is very likely, that humans and animals are always exposed to mixtures of mycotoxins rather than to individual compounds. Therefore, risk assessments should consider mixture toxicity data. In the present study the combination of AFB1, OTA and ZEA was tested for genotoxicity in rat bone marrow and blood leukocytes after 15, 30 and 60 days treatment. The level of DNA damage was determined by the comet assay. The tail intensity and Olive tail moment in leukocytes and bone marrow cells were significantly higher than in controls. At the same time, the level of DNA damage in bone marrow cells was higher than in leukocytes. The data suggests that prolonged exposure to mycotoxins combination through food consumption can induce DNA damage contributing to the harmful effects in vivo.

• 셀메드
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• 제2권4호
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• pp.35.1-35.11
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• 2012

The homeopathic remedy Chelidonium majus 200C (Chel-200) is traditionally used by homeopathic practitioners in liver ailments arising out of hepatotoxicity. The present investigation was aimed at examining whether vitamin C (L-ascorbic acid or AA), used in both traditional and orthodox medicines, can show better effects when used in combination with Chel-200, in favorably modifying the toxicological effects induced by the chronic feeding of p-dimethylaminoazobenzene (p-DAB, initiator) and phenobarbital (PB, promoter) in mice for 7 days through 120 days to induce hepatotoxicity and liver tumors. Mice were euthanized at 7, 15, 30, 60, 90, and 120 days of carcinogen feeding to assess various cytogenetical, biochemical and histological changes occurring in them. In a placebo controlled study, Chel-200 or the respective placebo (Alcohol-200C or Alc, "vehicle" of homeopathic drug), was orally administered to toxicant-fed mice. Sub-groups of the mice receiving Chel-200 were also fed either AA or an Alc placebo and their individual and conjoint effects were studied against the respective controls, to evaluate if the combination therapy of Chel-200 with AA can be of additional help in the amelioration of the toxicities generated by the toxicants. The combined feeding of Chel-200 and AA appeared to reduce the cytotoxic and genotoxic effects significantly, when compared to either only the Chel-200 or AA fed group. A similar trend was also obtained in the results of scanning and transmission electron microscopic studies of the livers. Experiments in other mammalian models are warranted to confirm if these drugs in combination could be used in palliative care of human patients with liver diseases including cancer.

• Toxicological Research
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• 제35권2호
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• pp.137-154
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• 2019

Triclosan (TCS) is an antimicrobial compound used in consumer products. The purpose of current study was to examine toxicology and risk assessment of TCS based on available data. Acute toxicities of oral, transdermal and inhalation routes were low, and phototoxicity and neurotoxicity were not observed. Topical treatment of TCS to animal caused mild irritation. TCS did not induce reproductive and developmental toxicity in rodents. In addition, genotoxicity was not considered based on in vitro and in vivo tests of TCS. It is not classified as a carcinogen in international authorities such as International Agency for Research on Cancer (IARC). No-observed-adverse-effect level (NOAEL) was determined 12 mg/kg bw/day for TCS, based on haematoxicity and reduction of absolute and relative spleen weights in a 104-week oral toxicity study in rats. Percutaneous absorption rate was set as 14%, which was human skin absorption study reported by National Industrial Chemicals Notification and Assessment Scheme (NICNAS) (2009). The systemic exposure dosage (SED) of TCS has been derived by two scenarios depending on the cosmetics usage of Koreans. The first scenario is the combined use of representative cosmetics and oral care products. The second scenario is the combined use of rinse-off products of cleansing, deodorants, coloring products, and oral care products. SEDs have been calculated as 0.14337 mg/kg bw/day for the first scenario and 0.04733 mg/kg bw/day for the second scenario. As a result, margin of safety (MOS) for the first and second scenarios was estimated to 84 and 253.5, respectively. Based on these results, exposure of TCS contained in rinse-off products, deodorants, and coloring products would not pose a significant health risk when it is used up to 0.3%.

• Environmental Analysis Health and Toxicology
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• 제14권1_2호
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• pp.1-12
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• 1999

Recently, several new methods for the detection of genetic damages in vitro and in vivo based on molecular biological techniques were introduced according to the rapid progress in toxicology combined with cellular and molecular biology. Among these methods, mouse lymphoma thymidine kanase (tk) gene forward mutation assay, single cell gel electrophoresis (comet assay) and transgenic animal and cell line model as a target gene of lac I (Big Blue) and lac Z (Muta Mouse) gene mutation are newly introduced based on molecular toxicological approaches. The mouse lymphoma tk$\^$+/-/ gene assay (MOLY) using L5178Y tk$\^$+/-/ mouse lymphoma cell line is one of the mammalian forward mutation assays, and has many advantages and more sensitive than hprt assay. The target gene of MOLY is a heterozygous tk$\^$+/-/ gene located in 11 chromosome, so it is able to detect the wide range of genetic changes like point mutation, deletion, rearrangement, and mitotic recombination within tk gene or deletion of entire chromosome 11. The comet assay is a rapid, simple, visual and sensitive technique for measuring and analysing DNA breakages in mammalian cells, Also, transgenic animal and cell line models, which have exogenous DNA incorporated into their genome, carry recoverable shuttle vector containing reporter genes to assess endogenous effects or alteration in specific genes related to disease process, are powerful tools to study the mechanism of mutation in vivo and in vitro, respectively. Also in vivo acridine orange supravital staining micronucleus assay by using mouse peripheral reticulocytes was introduced as an alternative of bone marrow micronucleus assay. In this respect, there was an International workshop on genotoxicity procedure (IWGTP) supported by OECD and EMS (Environmental Mutagen Society) at Washington D. C. in March 25-26, 1999. The objective of IWGTP is to harmonize the testing procedures internationally, and to extend to finalization of OECD guideline, and to the agreement of new guidelines under the International Conference of Harmonization (ICH) for these methods mentioned above. Therefore, we introduce and review the principle, detailed procedure, and application of MOLY, comet assay, transgenic mutagenesis assay and supravital staining micronucleus assay.

• 약학회지
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• 제55권2호
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• pp.81-90
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• 2011

Most antineoplastic agents are nonselective in their mechanism of action, affecting noncancerous as well as cancerous cells, and resulting in acute effects such as irritation of mucous membranes and chronic effects such as genotoxicity, teratogenicity, and carcinogenicity. Healthcare workers occupationally exposed to antineoplastic agents are at risk. The present study aimed to develop and apply methods to monitor occupational exposure to antineoplastic agents, using cyclophosphamide (CP) as the model compound. To monitor environmental and biological exposure, potentially contaminated surfaces were wiped and 24 hour urine samples were collected from workers. Liquid chromatography combined with tandem mass spectrometry was performed, with a limit of detection of 0.05 ng/ml. Measurable amounts of CP were detected on 92% of the sampled surfaces, with a geometric mean of 175.22 $ng/m^2$. Despite the environmental contamination of the model compound, CP was below the detection limit in all urine samples. If workplace contamination cannot be completely avoided, it is importance to reduce exposure to the lowest possible levels. To this aim, efforts to minimize occupational exposure along with biological and environmental monitoring are required. The standardized sampling techniques, and specific and sensitive analytical methods reported in this study may be helpful in assessing occupational exposure and devising strategies to reduce exposure.

• 환경생물
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• 제28권4호
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• pp.212-217
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• 2010

각종 유전독성학적 물질로 인한 생물체내의 영향을 평가해보기 위해 E. fetida를 대상으로 본 연구를 수행하였다. 염화수은에 대한 DNA 손상을 알아보는 실험에서는 노출 시간에 상관없이 노출 농도에 비례한 유전자의 손상이 나타났다. 방사선이 지렁이의 DNA 손상에 미치는 영향을 알아본 실험에서도 역시 방사선 총 선량의 증가에 따라 DNA 손상이 증가하는 경향을 보였다. 염화수은에 48시간 동안 노출시키고 방사선을 조사한 지렁이의 세포를 comet assay하면, 수은 단독 처리군이나 방사선 단독 처리군에 비해 DNA의 손상이 유의적으로 크게 나타났다. 염화수은과 방사선 모두에 복합처리 된 지렁이의 DNA 손상치는 각각 단독 처리한 지렁이의 DNA 손상치를 합한 값보다 크게 나타나 두 요인의 상승작용이 확인되었다. 본 연구를 통해 지렁이의 세포내에서 수은과 방사선이 야기하는 DNA 손상을 측정하고, 두 인자의 복합처리에 따른 유전독성 상승효과를 관찰할 수 있었다. 이는 중금속과 방사선의 복합적인 효과를 나타낸 기존의 여러 연구결과와도 비교가 가능한 연구라고 사료되며, 향후 이를 보완하고 더 정확한 평가를 위해 지렁이 세포 내에서의 스트레스 반응 측정이나 효소 활성 실험등을 추가로 수행하여야 할 것이라고 생각된다.

• 한국식품영양학회지
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• 제26권3호
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• pp.383-390
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• 2013

본 연구에서는 겨우살이 열수 추출물인 미슬로 C의 안전성을 검토하고자 유전 독성 및 실험동물을 이용한 안전성 검사를 실시하였다. 미슬로 C의 미생물 돌연변이 실험을 S. typhimurium의 히스티딘 요구성 균주와 E. coli의 트립토판 요구성 균주를 이용하여 대사 활성계 적용 및 비적용 하에서 복귀돌연변이 시험을 실시한 바, $5,000{\mu}g/plate$의 처리 농도까지 복귀돌연변이 집락은 나타나지 않았다. ICR 마우스에게 500, 1,000 및 2,000 mg/kg를 경구 투여하고, 골수세포를 수집하여 소핵을 측정한 결과, 정상마우스의 경우와 비교하여 유의한 소핵은 관찰되지 않았기에 미슬로 C는 유전독성을 유발하지 않는 것으로 판단되었다. 식품의약안전청의 의약품 등의 독성시험기준에 따라 암 수 SD 계열의 랫드에 시험물질을 0, 500, 1,000 및 2,000 mg/kg/day의 용량으로 1회 경구 투여한 후, 14일간의 체중 변화 및 사망률을 조사한 결과, 대조군과 비교하여 유의한 체중 변화는 없었으며, $LD_{50}$은 2,000 mg/kg 이상인 것으로 사료된다. 또한 0, 250, 500 및 1,000 mg/kg/day의 용량으로 13주간 반복 투여하면서 실험동물의 일반증상, 체중변화, 혈액 및 혈액생화학적 변화, 부검소견, 조직학적인 변화를 관찰하였다. 시험기간 중 암 수 모든 군에서 시험물질 투여에 기인한 일반적인 증상 변화는 관찰되지 않았고, 시험물질의 반복 투여로 인한 사망 마우스 역시 관찰되지 않았다. 따라서 미슬로 C를 13주간의 랫드에 대한 13주 반복 경구 투여 결과, 무독성량은 최소한 1,000 mg/kg 이하인 결과를 나타냈으며, 이 농도에서 독성을 유발하는 표적장기는 관찰되지 않았다.