• Restorative Dentistry and Endodontics
• /
• 제31권1호
• /
• pp.36-49
• /
• 2006

본 연구의 목적은 기존 상용화된 근관 봉함재인 레진계 봉함재 (AH 26, AH Plus), 산화 아연 유지놀계 봉함재(Tubliseal EWT Pulp Canal Sealer EWT), 수산화 칼슘계 봉함재 (Sealapex), 기존의 인산삼칼슘계 봉함재(Sankin Apatite type I, II, III)와 새로이 개발된 인산칼슘계 근관 봉함재 (CAPSEAL I, CAPSEAL II)의 세포독성과 유전독성을 비교 평가하고자 하였다. MTT test를 통해 세포독성을 평가하였으며 미생물을 이용한 복귀돌연변이 시험 (Ames test)으로 유전독성을 평가하였다. 이 연구의 결과는 아래와 같다. 1. 즉시군이 24시간군에 비해 MTT assay에서 세포독성이 높게 나타났다 (p<0.001). 2. 즉시군에서 CAPSEAL I과 CAPSEAL II는 AH 26, AH Plus, Tubliseal EWT Pulp Canal Sealer EWT, Sealapex와 SARCS II 보다 낮은 세포독성을 보였다 (p<0.01). 3. 즉시군에서 AH 26은 TA98과 TA100에 각각 S9 fraction을 처리한 경우와 그렇지 않은 경우 모두 유전독성을 나타냈으며, AH Plus 또한 TA100에 S9 fraction을 처리한 경우와 그렇지 않은 경우 유전독성을 나타냈다. 4. 즉시군에서 Tubliseal EWT, Pulp Canal Sealer EWT Sealapex가 TA100균주에 S9 fraction을 처리하였을 때 유전독성 양성반응이 나타났으며, 그 외의 경우는 모두 음성반응을 나타냈다. 5. 24시간군에서는 SARCS II가 TA98균주에서 S9 fraction처리했을 때와 처리하지 않았을 때 모두 유전독성이 나타났고, AH 26은 TA98에 S9 fraction을 처리하였을 때 유전독성이 나타났다 그 외의 경우는 모두 음성반응을 보였다. 6. CAPSEAL I과 CAPSEAL II는 유전독성에서 모두 음성반응을 나타냈다. 7. CAPSEAL I과 CAPSEAL II 두 근관봉함재 간에는 세포독성실험과 유전독성실험에서 즉시군과 24시간군 모두에서 통계학적으로 유의할 만한 차이를 보이지 않았다.

• Toxicological Research
• /
• 제32권4호
• /
• pp.289-300
• /
• 2016

Non-genotoxic carcinogens are substances that induce tumorigenesis by non-mutagenic mechanisms and long term rodent bioassays are required to identify them. Recent studies have shown that transcription profiling can be applied to develop early identifiers for long term phenotypes. In this study, we used rat liver expression profiles from the NTP (National Toxicology Program, Research Triangle Park, USA) DrugMatrix Database to construct a gene classifier that can distinguish between non-genotoxic carcinogens and other chemicals. The model was based on short term exposure assays (3 days) and the training was limited to oxidative stressors, peroxisome proliferators and hormone modulators. Validation of the predictor was performed on independent toxicogenomic data (TG-GATEs, Toxicogenomics Project-Genomics Assisted Toxicity Evaluation System, Osaka, Japan). To build our model we performed Random Forests together with a recursive elimination algorithm (VarSelRF). Gene set enrichment analysis was employed for functional interpretation. A total of 770 microarrays comprising 96 different compounds were analyzed and a predictor of 54 genes was built. Prediction accuracy was 0.85 in the training set, 0.87 in the test set and increased with increasing concentration in the validation set: 0.6 at low dose, 0.7 at medium doses and 0.81 at high doses. Pathway analysis revealed gene prominence of cellular respiration, energy production and lipoprotein metabolism. The biggest target of toxicogenomics is accurately predict the toxicity of unknown drugs. In this analysis, we presented a classifier that can predict non-genotoxic carcinogenicity by using short term exposure assays. In this approach, dose level is critical when evaluating chemicals at early time points.

• 한국물환경학회지
• /
• 제22권6호
• /
• pp.1123-1129
• /
• 2006

대부분의 polycyclic aromatic hydrocarbons (PAHs) 은 최우선 오염물질로 간주되어지고 있는 매우 유독한 물질이다. Pyrene은 PAHs들 중에서도 그 유독성은 가히 심각하다. 그리고 Pyrene과 다른 PAHs화합물들은 물에 잘 용해가 되지 않는 소수성 성질을 가지고 있어 화학적 또는 생물학적 분해가 용이하지 않다. 이러한 성질을 극복하기 위하여 본 연구에서는 Pyrene을 대표 물질로 하여 2 단계 오존처리를 하였다. 첫 단계에서 Pyrene을 무극성인 핵산 용매에 대량 (2000 mg/L) 으로 녹여 오존처리를 하였다. 이때 Pyrene은 극성 분자들, 즉 알콜과 알데하이드 그리고 에시드 기능기를 가지는 물질들로 변화되었으며 이 변화된 물질들을 다시 극성 용매, 물에 녹여 두 번째 오존처리를 하였다. 두 번째 오존 처리된 Pyrene의 부산물들과 중간생성물들은 생물학적 처리로 가능한지 연구되어지기 위해 $BOD_5$와 COD 그리고 E-coli toxicity tests가 이루어졌다. 그 결과 오존 처리된 Pyrene은 유독하지도 않았고 Pyrene의 부산물들과 중간생성물들은 생물학적 처리가 용이하여졌다. Gas chromatograph (GC) 분석을 통해 Pyrene의 부산물들과 중간생성물들을 밝혀내었다. 이 연구를 토대로 소수성 성질을 가지는 많은 방향족 물질들을 처리하기가 매우 용이해졌다.

• 한국식품위생안전성학회지
• /
• 제27권2호
• /
• pp.141-145
• /
• 2012

Zizyphi spinosi semen (Z. spinosi) has been used in traditional Chinese medicine for the treatment of rheumatoid arthritis and wounds. However, toxicity in high doses was often observed due to the presence of alkaloids. This study was conducted to investigate the potential genotoxicity of Z. spinosi in vitro and in vivo. This was examined by the Bacterial reverse mutation (Ames) test using Salmonella typhimurium TA98, TA100, TA1535, TA1537 and Escherichia coli WP2uvrA, Chromosomal aberration was investigated using Chinese hamster lung cells and the micronucleus test using mice. Z. Spinosi did not induce mutagenicity in the Ames test, and it did not produce chromosomal aberration in Chinese hamster lung cells with and without metabolic activation, nor in the micronucleated polychromatic erythrocytes in the bone marrow cells in mice. Based on these results, it is concluded that Z. spinosi does not have mutagenic potential under the conditions examined in each study.

• 한국미생물·생명공학회지
• /
• 제42권2호
• /
• pp.152-161
• /
• 2014

The in vitro antimicrobial potential of the unexplored Moringa oleifera seed coat (SC) was evaluated against some Gram-positive and Gram-negative bacteria and yeast pathogens. Antimicrobial studies with various solvent extracts indicated ethyl acetate to be the best extractant, which was used for the rest of the antimicrobial studies as it tested neither toxic nor mutagenic. Gram-positive bacteria including a methicillin resistant Staphylococcus aureus (MRSA) strain were more susceptible with a minimum inhibitory concentration (MIC) range of 0.03-0.04 mg/ml. The antimicrobial pharmacodynamics of the extract exhibited both concentration-dependent and time-dependent killing. Most of the test organisms exhibited a short post antibiotic effect (PAE) except Enterococcus faecalis, Staphylococcus aureus, and Klebsiella pneumoniae 1, which exhibited longer PAEs. Amongst the major phytoconstituents established, flavonoids, diterpenes, triterpenes and cardiac glycosides exhibited inhibitory properties against most of the test organisms. The identified active phytochemicals of the M. oleifera seed coat exhibited antimicrobial potential against a wide range of medically important pathogens including the multidrug-resistant bugs. Hence, the M. oleifera seed coat, which is usually regarded as an agri-residue, could be a source of potential candidates for the development of drugs or drug leads of broad spectrum that includes multidrug-resistant bugs, which are one of the greatest concerns of the $21^{st}$ century.

• Environmental Analysis Health and Toxicology
• /
• 제27권
• /
• pp.14.1-14.6
• /
• 2012

Objectives: The root barks of Periploca sepium Bge. (P. sepium) has been used in traditional Chinese medicine for healing wounds and treating rheumatoid arthritis. However, toxicity in high-doses was often diagnosed by the presence of many glycosides. The potential mutagenicity of P. sepium was investigated both in vitro and in vivo. Methods: This was examined by the bacterial reverse mutation (Ames) test using Escherichia coli WP2uvrA and Salmonella typhimurium strains, such as TA98, TA100, TA1535, and TA1537. Chromosomal aberrations were investigated using Chinese hamster lung cells, and the micronucleus test using mice. Results: P. sepium did not induce mutagenicity in the bacterial test or chromosomal aberrations in Chinese hamster lung cells, although metabolic activation and micronucleated polychromatic erythrocytes were seen in the mice bone marrow cells. Conclusions: Considering these results, it is suggested that P. sepium does not have mutagenic potential under the conditions examined in each study.

• Toxicological Research
• /
• 제33권4호
• /
• pp.299-304
• /
• 2017

Thallium and its compounds are a class of highly toxic chemicals that cause wide-ranging symptoms such as gastrointestinal disturbances; polyneuritis; encephalopathy; tachycardia; skin eruptions; hepatic, renal, cardiac, and neurological toxicities; and have mutagenic and genotoxic effects. The present research aimed to evaluate the efficacy of the chelating agents deferasirox (DFX) and deferiprone (L1) in reducing serum and tissue thallium levels after the administration of thallium (III), according to two different dosing regimens, to several groups of Wistar rats for 60 days. It was hypothesized that the two chelators might be more efficient as a combined therapy than as monotherapies in removing thallium (III) from the rats' organs. The chelators were administered orally as either single or combined therapies for a period of 14 days. Serum and tissue thallium (III) and iron concentrations were determined by flame atomic absorption spectroscopy. Serum and tissue thallium (III) levels were significantly reduced by combined therapy with DFX and L1. Additionally, iron concentrations returned to normal levels and symptoms of toxicity decreased.

• Journal of Microbiology and Biotechnology
• /
• 제29권10호
• /
• pp.1629-1635
• /
• 2019

Azo dyes are recalcitrant pollutants, which are toxic, carcinogenic, mutagenic and teratogenic, that constitute a significant burden to the environment. The decolorization and the mineralization efficiency of Remazol Brillant Orange 3R (RBO 3R) was studied using a probiotic consortium (Lactobacillus acidophilus and Lactobacillus plantarum). Biodegradation of RBO 3R (750 ppm) was investigated under shaking condition in Mineral Salt Medium (MSM) solution at pH 11.5 and temperature $25^{\circ}C$. The bio-decolorization process was further confirmed by FTIR and UV-Vis analysis. Under optimal conditions, the bacterial consortium was able to decolorize the dye completely (>99%) within 12 h. The color removal was 99.37% at 750 ppm. Muliplex PCR technique was used to detect the Lactobacillus genes. Using phytotoxicity, cytotoxicity, mutagenicity and biototoxicity endpoints, toxicological studies of RBO 3R before and after biodegradation were examined. A toxicity assay signaled that biodegradation led to detoxification of RBO 3R dye.

• 한국식품영양과학회지
• /
• 제36권8호
• /
• pp.960-964
• /
• 2007

천연생리활성물질 소재로서 파고지 추출물의 안전성을 검증하기 위하여 렛트에 대한 단회 경구투여 독성 평가와 복귀돌연변이평가를 실시하였다. 파고지 에탄올 추출분말 2 g/kg, 5 mL를 암${\cdot}$수 각각 5마리씩 경구 투여한 후 14일 동안의 일반증상, 체중변화 및 부검시의 육안적 소견을 관찰한 결과, 사망례, 일반증상 및 체중변화는 관찰되지 않았고 부검결과에서도 특이할 만한 육안적 이상소견은 관찰되지 않아, 파고지 추출물은 $LD_{50}$값이 렛트 체중 kg당 2g 이상이며 단회 경구 투여에 대한 독성을 가지는 않는 것으로 평가되었다. 파고지 추출분말의 복귀돌연변이 유발성 여부는, 히스티딘 요구성 Salmonella Typhimurium TA98, TA100, TA1535, TA1537 균주 및 트립토판 요구성 Escherichia coli WP2uvrA(pKM101) 균주를 이용하여 S9 mix 첨가 여부에 따라 실험하였다. 용량설정시험 결과, S9 mix 첨가 여부에 관계없이 사용한 모든 시험균주에서 생육저해가 관찰되었다. 시험물질의 석출은 S9 mix 첨가 여부와 상관없이 사용한 모든 시험균주의 1,250, 2,500 및 5,000 ${\mu}g/plate$에서 관찰되었지만 콜로니 계수에는 영향이 없었다. 따라서, 본 시험의　용량은 S9 mix 미첨가 TA100, TA1537 균주 및 S9 mix 첨가 RA1535 균주의 경우에는 생육저해가 관찰된 625 ${\mu}g/plate$를, S9 mix 첨가 여부에 관계없이 TA98 균주 및 S9 mix 첨가TA100, TA1537, WP2uvrA(pKM101) 균주의 경우에는 생육저해가 관찰된 1,250 ${\mu}g/plate$를, S9 mix 미첨가의 TA1535 및 WP2uvrA(pKM101) 균주의 경우에는 2,500 ${\mu}g/plate$를 최고용량으로 하였고, 그 이하 공비 2로 최고용량을 포함한 5용량의 시험물질군과 음성대조군 및 양성대조군으로 하여 실험을 실시하였다. 그 결과, 모든 시험균주에서 시험물질에 의한 복귀변이 콜로니수는 S9 mix의 첨가 여부에 관계없이 용량의존적으로 증가되지 않았으며, 음성대조군과 비교하여 2배 이상의 증가를 보이지 않았다. 시험물질에 의한 균주의 생육저해는 S9 mix첨가 여부에 관계없이 사용한 모든 시험균주의 최고용량에서 관찰되었다. 시험물질의 석출은 S9 mix 첨가 여부에 관계없이 1,250 및 2,500 ${\mu}g/plate$에서 관찰되었지만 콜로니 계수에는 영향이 없는 것으로 나타났다.

• Molecular & Cellular Toxicology
• /
• 제1권3호
• /
• pp.172-178
• /
• 2005

[ $21{\alpha}$ ]- and ${\beta}$-Methylmelianodiol were isolated as the inhibitor of IL-5 bioactivity from Poncirus tripoliata. To develope as an anti-septic drug, the genotoxicity of $21{\alpha}\;-and\;{\beta}-methylmelianodiol$ was subjected to high throughput toxicity screening (HTTS) because they revealed strong IL-5 inhibitory activity and limitation of quantity. Mouse lymphoma thymidine kinase ($tk^{+/-}$) gene assay (MOLY), single cell gel electrophoresis (Comet) assay in mammalian cells and Ames reverse mutation assay in bacterial system were used as simplified, inexpensive, short-term in vitro screening tests in our laboratory. These compounds are not mutagenic in S. typhimurium TA98 and TA100 strains both in the presence and absence of metabolic activation. Before performing the comet assay, $IC_{20}$ of $21{\alpha}-methylmelianodiol$ was determined the concentration of $25.51\;{\mu}g/mL\;and\;21.99\;{\mu}g/mL$ with and without S-9, respectively. Also $21{\beta}-methylmelianodiol$ was determined the concentration of $24.15\;{\mu}g/mL\;and\;\;22.46\;{\mu}g/mL$ with and without S-9, respectively. In the comet assay, DNA damage was not observed both $21{\alpha}-methylmelianodiol\;and\;21{\beta}-methylmelianodiol$ in mouse lymphoma cell line. Also, the mutant frequencies in the treated cultures were similar to the vehicle controls, and none of $21{\alpha}\;-and\;{\beta}-methylmelianodiol$ with and without S-9 doses induced a mutant frequency over. twice the background. It is suggests that $21{\alpha}\;-and\;{\beta}-methylmelianodiol$ are non-mutagenic in MOLY assay. The results of this battery of assays indicate that $21{\alpha}\;-and\;{\beta}-methylmelianodiol$ have no genotoxic potential in bacterial or mammalian cell systems. Therefore, we suggest that $21{\alpha}\;-and\;{\beta}-methylmelianodiol$, as the optimal candidates with both no genotoxic potential and IL-5 inhibitory effects must be chosen.