• Journal of Environmental Health Sciences
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• v.28 no.2
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• pp.71-80
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• 2002

To evaluate the skin toxicity of topical cyclohexane application (25mg/$\textrm{cm}^2$) was sequentially applied to the rat skin for four days. On the histopathological findings in the light micrographs, neutrophils and engulfed neutrophils are seen, and many cytoplasmic processes were appeared in proliferated layer whereas in the dermis area, increased numbers of fibroblast, accumulation of neutrophil and lipid droplets are demonstrated. On the other hand, applying the cyclohexane to the rat skin led to the remarkable rise of cutaneous xanthine oxidase activity and similar activities of superoxide dismutase and glutathione peroxidase and glutathione content and declined activity of glutathione S-transferase compared with control group. Especially the remarkably decreased activity of aniline hydroxylase (AH) was appeared in skin as little as scarcely determined. Furthermore, the applying the cyclohexane to skin led to the significantly increased activity of hepatic AH and alcohol dehydrogenase. These results indicate that oxygen free radical and intermediate metabolite of cyclohexane may be responsible for structural changes in skin by cyclohexane application to rat skin.

• Molecular & Cellular Toxicology
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• v.2 no.1
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• pp.54-59
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• 2006

The toxicity of cadmium on Caenorhabditis elegans was investigated to identify sensitive biomarkers for environmental monitoring and risk assessment. Stress-related gene expression were estimated as toxic endpoints Cadmium exposure led to an increase in the expression of most of the genes tested. The degree of increase was more significant in heat shock protein-16.1, metallothionein-2, cytochrome p450 family protein 35A2, glutathione S-transferase-4, superoxide dismutase-1, catalase-2, C. elegans p53-like protein-1, and apoptosis enhancer-1 than in other genes. The overall results indicate that the stress-related gene expressions of C. elegans have considerable potential as sensitive biomarkers for cadmium toxicity monitoring and risk assessment.

• International Journal of Stem Cells
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• v.17 no.2
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• pp.141-146
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• 2024

Recent advancements in organoid technology have led to a vigorous movement towards utilizing it as a substitute for animal experiments. Organoid technology offers versatile applications, particularly in toxicity testing of pharmaceuticals or chemical substances. However, for the practical use in toxicity testing, minimal guidance is required to ensure reliability and relevance. This paper aims to provide minimal guidelines for practical uses of kidney organoids derived from human pluripotent stem cells as a toxicity evaluation model in vitro.

• Food Science and Preservation
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• v.19 no.3
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• pp.451-454
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• 2012

Endosulfan is an organochlorine pesticide that is widely used throughout the world for higher agricultural production. Its extreme toxicity, however, has caused health and environment concerns that have led to an interest in detoxification. In this study, the radiolytic degradation of endosulfan was investigated. Endosulfan in methanol solution (100 ppm) was irradiated at 0, 10, 30, and 50 kGy, and subsequent changes in immune toxicity and degradation of endosulfan were observed. The concentration of endosulfan that was used in this experiment did not affect the cell proliferation. The irradiation of endosulfan decreased the production of NO, indicating a decrease in the immune toxicity of endosulfan by irradiation. The concentration of endosulfan was significantly reduced by irradiation in a dose-dependent manner. The results suggest that gamma irradiation can degrade endosulfan and can reduce its immune toxicity.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3419-3424
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• 2014

Background: Our aim was to conduct a meta-analysis to compare the efficacy and safety of pemetrexed and docetaxel for non-small cell lung cancer (NSCLC). Materials and Methods: We systematically searched the Cochrane Library, PubMed, Embase, China Biology Medicine Database for randomized controlled trials (RCTs) comparing the efficacy and toxicities of pemetrexed versus docetaxel as a treatment for advanced NSCLC. We limited the languages to English and Chinese. Two reviewers independently screened articles to identify eligible trials according to the inclusion and exclusion criteria and assessed the methodological quality of included trials, and then extracted data. The meta-analysis was performed using STATA12.0. Results: Six RCTs involving 1,414 patients were identified. We found that there was no statistically significant differences in overall response rate, survival time, progression-free survival, disease control rate, and 1-2yr survival rate (p>0.050) but it is worthy of mention that patients in the pemetrexed arms had significantly higher 3-yr survival rate (P=0.002). With regard to the grade 3 or 4 hematological toxicity, compared with docetaxel, pemetrexed led to lower rate of grade 3-4 febrile neutropenia, neutropenia, and leukocyts toxicity (p<0.001). There was no significant difference in anemia between the two arms (p=0.08). In addition, pemetrexed led to higher rate of grade 3-4 thrombocytopenia toxicity (p=0.03). As for the non-hematological toxicities, compared with docetaxel, pemetrexed group had lower rate of grade 3-4 diarrhea and alopecia. Conclusions: Pemetrexed was almost as effective as docetaxel in patients with advanced NSCLC. At the same time, pemetrexed might increase the 3-yr survival rate. As for safety, pemetrexed led to lower rate of grade 3-4 febrile neutropenia, neutropenia, leukocytes, diarrhea and alopecia toxicity. However, it was associated with a higher rate of grade 3-4 thrombocytopenia.

• Journal of Environmental Health Sciences
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• v.38 no.1
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• pp.1-7
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• 2012

Carbon nanotubes (CNTs) stand at the frontier of nanotechnology and are destined to stimulate the next industrial revolution. Rapid increase in their production and use in the technology industry have led to concerns over the effects of CNT on human health and the environment. The prominent use of CNTs in biomedical applications also increases the possibility of human exposure, while properties such as their high aspect ratio (fiber-like shape) and large surface area raise safety concerns for human health if exposure does occur. It is crucial to develop viable alternatives to in vivo tests in order to evaluate the toxicity of engineered CNTs and develop validated experimental models capable of identifying CNTs' toxic effects and predicting their level of toxicity in the human respiratory system. Human lung epithelial cells serve as a barrier at the interface between the surrounding air and lung tissues in response to exogenous particles such as air-pollutants, including CNTs. Monolayer culture of the key individual cell types has provided abundant fundamental information on the response of these cells to external perturbations. However, such systems are limited by the absence of cell-cell interactions and their dynamic nature, which are both present in vivo. In this review, we suggested two viable alternatives to in vivo tests to evaluate the health risk of human exposure to CNTs.

• Journal of Ginseng Research
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• v.27 no.4
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• pp.171-177
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• 2003

Previously we have reported that administration of Korean red ginseng water extract (KRG-WE) plays both preventive and therapeutic roles in testicular toxicity of guinea pigs exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Further study was carried out to verify the beneficial role of Korean red ginseng in TCDD-induced testicular toxicity with different animal species by different route of administration. Korean red ginseng crude saponin (KRG-CS) was prepared by Diaion HP-20 adsorption chromatography. One hundred twenty rats (Sprauge Dawley, 200${\pm}$10 g) were divided into 6 groups. The normal control group (NC) received vehicle (i.p.) and saline (p.o.). Predetermined dosage of TCDD (40 $\mu\textrm{g}$/kg b.w., i.p.) was administered to single TCDD-treated (TT) and test (CS) groups. KRG-CS was admin-istered (p.o.) at daily doses of 5 (CS5), 10 (CS10),20 (CS2O) and/or 40 mg/kg b.w. (CS40) for 5 weeks, starting 1 week before the TCDD-exposure. Body weight gain, organ weights, and sperm quality were investigated. Decrease in body weight gain induced by TCDD was greatly attenuated by KRG-CS in a dose-dependent manner. Testicular weight, sperm head counts and ratio of sperm with progressive movement in TT group decreased significantly but those parameters were improved by the treatment of KRG-CS in a dose-dependent manner. This result led us to conclude that crude saponin might be the active ingredient of Korean red ginseng that attenuates the testicular toxicity induced by TCDD.

• Journal of Forest and Environmental Science
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• v.26 no.3
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• pp.171-179
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• 2010

Effect of chromium (Cr) stress on antioxidant enzyme activities and malondialdehyde (MDA) content were investigated in leaves and roots of mangrove (italic (L.) Druce) seedlings. Cr toxicity effects were also assessed on young seedlings. The seedlings were grown in green house condition for three months in nutrient solution with 0, 0.5, 1, 1.5, 2, 2.5, and 3 mg $L^{-1}$ $CrCl_3$. This study showed that Cr led to the change of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) and activities at different concentrations. The activity of antioxidant enzymes in leaves of K. candel seedlings indicates that enzymes engaged in antioxidant defense in certain level especially in low concentration of Cr treatments. The activities of SOD and POD were activated by Cr in the root level, while CAT activity was inhibited. CAT activity decreased in response to high concentrations of Cr. In the present study indicated that SOD in root was active in scavenging the superoxide produced by Cr. Both in roots and leaves, an increase in malondialdehyde (MDA) content was observed with increase in metal concentration and exposure periods. Our finding indicated that the high concentration of excessive Cr supply may interfere with several metabolic processes of seedlings, causing toxicity to plants as exhibited by chlorosis, necrosis, photosynthetic impairing and finally, plant death.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.156-163
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• 2001

Vanadium has been known as environmental polluants resulted from the burning of fossil fuels in nature. It led to toxic responses by prooxidant activity, inducing free radicals and the accumulation in the tissues. Recently, there has been growing interest in an essential nutritional requirement of vandium and especially the treatment of diabetes. But because of its strong toxicity, thease chemicals have narrow safety margin. In order to reduce metal toxicity, and increase absorption and biological activities, metal ions such as selenium and chromium were uptaken in yeast cells. In this study, Vanadium yeast was prepared by uptaking vanadate in yeast cells. Vanadate induced hematological and biochemical changes in the experimental rat blood were inhibited by the treatments of vanadium yeast. Lipid peroxidation and catalase activity were significantly increased in kidney and liver after a single intraperitoneal injection of vanadate to rats. However, these observations were apparently reduced in the vanadium yeast treated group. Vanadium amount in blood, kidney and liver after a single intraperitoneal injection of vanadium yeast was significantly reduced than that of vanadate treated group. In conclusion, vanadium yeast uptaken vanadate in yeast cells could reduce toxic effects of vanadate.

• YAKHAK HOEJI
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• v.52 no.3
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• pp.212-218
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• 2008

Manganese is a naturally occurring element which is widespread in the environment. Also, manganese is an essential trace element and plays a key role in important biological reactions catalyzed by enzymes. However, exposure to high levels of manganese can cause toxicity in neurone and inhalation system, also damage in various tissues. We investigated the toxicity induced by manganese compound ($MnCl_2$) in cultured rat cardiomyocytes. Treatment of manganese to cultured cardiomyocyte led to cell death, reactive oxygen species (ROS) increase, and cytosolic caspase-3 activation. The ROS increase was related with the decreased level of glutathione. Expressions of ROS related genes such as heme oxygenase-1, thioredoxin reductase, and NADH quinone oxidase were significantly induced in manganese treated cells. These results suggest that manganese induce oxidative stress and apoptosis in cardiomyocytes, and may be the one of risk factors to cause heart dysfunction in vivo.