• Environmental Analysis Health and Toxicology
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• v.23 no.1
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• pp.47-51
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• 2008

The toxicity of environmental pollutants was measured between a image of the surface topography in HeLa cells using atomic force microscopy for the possibility of toxic effect measurement and environmental monitoring. A image of the surface topography by AFM were estimated as toxic endpoints. The surface topography by AFM was observed a change of the cell surface in the environmental pollutants, but the standard of the measurement requires for the dose-effect degree. The overall results indicate that the possibility of measurement using AFM were confirmed a dose-effect degree related toxic effects, but it requres correlation between more various biomarker and AFM's measurements if the possibility of the toxic effect measurement was established.

• Journal of Oriental Neuropsychiatry
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• v.10 no.1
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• pp.53-78
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• 1999

As the average life span have been lengthened and the rate of senile population have been raised, chronic degenerative diseases incident to aging has been increased rapidly and become a social problem. With this social background, recently, the facts that oxygen radicals(OR) have toxic effects on Central Nervous System and Peripheral Nervous System and cause neuropathy such as Parkinson's Disease, Alzheimer Disease have been turned out, and accordingly lots of studies on the mechanism of the toxic effects of OR on nerves, the diseases caused by OR and the approaches to curing the diseases have been made. The purpose of this study is to examine the toxic effects caused by Glucose Oxidase(GO) and the effects of herbal extracts such as Chilbokyeum(CBY), Chilbokyeumga Acori Rhizoma(CAR), Acori Rhizoma(AR) on the treatment of the toxic effects. For this purpose, experiments with the cultured cell from the cerebrums of new born mice were done. The results of these experiments were as follows. 1. GO, a oxygen radical, decreased the survival rate of the cultured cells on NR assay, MTT assay and amount of neurofilaments and increased the amount of total protein, lipid peroxidation and the amount of LDH. 2. CBY have efficacy of increasing the amount of neurofilaments and total protein and decreasing lipid peroxidation and the amount of LDH. 3. CAR have efficacy of increasing the amount of neurofilaments and total protein and decreasing lipid peroxidation and the amount of LDH. 4. AR have efficacy of increasing the amount of neurofilaments and total protein. From the above results, It is concluded that Chilbokyeumgamibang has marked efficacy as a treatment for the damages caused in the GO-mediated oxidative process. And Chilbokyeumgamibang is thought to have certain pharmacological effects on controlling over aging and treating Dementia. Further clinical study of this pharmacological effects of Chilbokyeumgamibang should be complemented.

• Industry Promotion Research
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• v.8 no.2
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• pp.67-80
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• 2023

This study analysis the effects of the relationship between LMX and affiliation-OCB, challenge-OCB which is voluntary behavior of organizational members. For this study, the effect of LMX on AOCB and COCB, as well as the mediating effect of AOCB behavior, the moderating role of toxic leadership, were analyzed. The results of studies are as follows. First, LMX had a positive effect on AOCB and COCB, respectively. Second, AOCB has a mediating-effect between LMX and COCB. and Third, toxic leadership confirmed the moderating-effect between LMX and AOCB, and finally the moderated-mediating-effect through AOCB in the relationship between LMX and COCB. Therefore, it was analyzed that the quality of the relationship between leader and member in the organization is an important factor in expanding the positive and voluntary behavior of members in the organization. In addition, since toxic leadership weakens positive and voluntary civic behavior for organizational members, it suggests the need for strategy to overcome toxic leadership for an efficient organization management.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.373-374
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• 2003

There were many studies on the effects of red tide dinoflagellates on shellfish populations (Nielsen and Stromgren, 1991; Lesser and Shumway, 1993; Luckenbach et al., 1993; Matsuyama et al., 1997; Li et al., 2001). However, these studies mainly focused on the toxic effects of dinoflagellates oui adults or juveniles. Interactions between dinoflagellates and bivalve larvae have not been understood comprehensively yet. (omitted)

• The Korea Journal of Herbology
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• v.20 no.4
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• pp.53-60
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• 2005

Objectives : This study was carried out to determine if Dendrobii Herba have protective effect against cell injury induced by various toxic agents in rat kidney slices. Water(DWe) and methanol(DMe) extracts were prepared for this experiment. Methods : Cell injury was estimated by measuring lactate dehydrogenase(LDH). Lipid peroxidation was examined by measuring malondialdehyde, a product of lipid peroxidation. Results : DMe prevented the LDH release by $CCl_4$, menadione, tert-butyl hydroperoxide and mercury treatment in vitro in kidney slices, but DWe prevented the LDH release by $CCl_4$ and mercury. DMe also prevented reduction in GSH and lipid peroxidation induced by $CCl_4$ and mercury. Conclusion : Thus, DMe may have more powerful efficacy on anti-oxidative effects when compared with DWe. And further studies have to be followed concerned with extraction of Dendrobii Herba and its change of effects.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7505-7513
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• 2014

Several toxic substances have been detected in plants which are responsible for animal and human diseases. Bracken fern (Pteridium aquilinum) is one example, widely distributed in many parts of the world. It is known to cause cancer in humans and other animals. In fact, man can be directly or indirectly exposed to the danger by consuming fern, contaminated water, milk, meat, and spore inhalation. Experimental studies have shown an association between bracken exposure and gastric cancer, and research has shown genotoxic and cytotoxic effects in vitro. This paper describes and reviews toxic, carcinogenic, genotoxic/cytotoxic, and immunomodulatory effects of bracken and included possible toxic agents. The chemistry of Ptaquiloside (PT) reactions is emphasized, along with bracken problems in livestock, possible pathways of exposure in man, and control for human health.

• Journal of Environmental Science International
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• v.4 no.2
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• pp.201-214
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• 1995

Design approach of upflow Anaerobic Sludge Blanket(UASB) process based on the biological kinetic parameters are known to be very difficult since the characteristics of the granular slut비e depends on the type of wastewater and size distribution of the granular sludge also depends on the upflow velocity in the UASB reactors. Furthermore, industrial wastewater containing toxic substances has been treated by UASB process without the clear knowledge of toxic effects on the granular slut형e. Hence, the present research was aimed on the intensive evaluation of biological kinetic parameters of the granular sludge in UASB reactor with and without toxic substance of 2, 4-dichlorophenol in order to present the basic design measures for UASB process design. The results could be summarized as follows. The biological kinetic parameters(k and Ks) considerably varied with the granular size of the sludge. Generally, 연e k and ks values of the granular sludge increased with the particle size of the granule. The biological kinetic parameters(k and Ks) of the granular sludge obtained from batch test were not applicable to design purpose of UASB process due to substrate diffusional limitation into the granular sludge in the completely mixed UASB reactors. The toxic effects on k and Ks greatly varied with the granular sixte. And as the toxicant concentration increased, the k value decreased while the Ks value increased. Inhibition constant(hi) for k with the toxicant of 2, 4-dichlorophenol varied from 0.5 to 2.3 depending on the granular sizes while the inhibition constant(Ki) for Ks varied from 20.7 to 80.1, showing the mixed inhibition.

• Journal of Microbiology
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• v.39 no.3
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• pp.206-212
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• 2001

Catechol and 4-chlorobenzoate (4CBA) which are produced from the biodegradation of a variety of aromatic and chloroaromatics have been recognized as toxic to living organisms. In this study, the toxic effects of catechol and 4-chlorobenzoate on gram-positive and -negative bacteria were examined in terms of survival, morphology, change in fatty acids and membrane protein composition. The survival rate of the organisms during treatment for 6 h was decreased, as the concentration of each aromatic was increased. Escherichia coli and Pseudomonas cells treated with catechol and 4CBA at concentrations causing a significant decrease in their viability, showed destructive openings in their cell envelopes. Bacills subtilis treated with the aromatics were reduced in cell size and Staphylococcus aureus cells displayed irregular rod shapes with wrinkled surfaces. The bacterial cells treated with 20 mM catechol showed increases in unsaturated fatty acids, but several saturated fatty acids were decreased. In the E. coli cells treated with 20 mM catechol, inner membrane proteins of 150 kDa and 105 kDa were decreased. But several kinds of the inner and outer membrane proteins were increased. In B. subtilis treated with 20 mM catechol, several kinds of proteins were increased or decreased in membrane proteins.

• Journal of Environmental Science International
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• v.20 no.10
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• pp.1221-1232
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• 2011

We investigated the toxic effects of difenoconazole on the development in the African clawed frog, Xenopus laevis. To test the toxic effects, frog embryo teratogenesis assays using Xenopus were performed. Embryos were exposed to various concentrations of difenoconazole (0-30 ${\mu}M$). $LC_{100}$ for difenoconazole was 30 ${\mu}M$, and the $LC_{50}$ determined by probit analysis was 27.19 ${\mu}M$. Exposure to difenoconazole concentrations ${\geq}$5 ${\mu}M$ resulted in 10 different types of severe external malformation. Histological examinations revealed dysplasia of the eye, heart, liver, somatic muscle, and swelling of the pronephric ducts. The tissue-specific toxic effects were investigated with an animal cap assay. Blood cells were normally induced at a high frequency by mSCF and activin A. However, the induction of blood cells was strongly inhibited by the addition of difenoconazole. Electron micrographs of tested embryos showed the degeneration of somatic muscle and the shrinkage of microvilli on pronephric duct. The gene expression of cultivated animal cap explants was investigated by reverse transcriptase-polymerase chain reaction (RT-PCR). It revealed that the expression of the blood-specific marker(${\beta}$-globin II) and muscle-specific marker (XMA) were more strongly inhibited than the neural-specific marker(XEn2) by the addition of difenoconazole.

• Journal of Environmental Science International
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• v.19 no.8
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• pp.1001-1012
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• 2010

We investigated the toxic effects of tebuconazole on development in the African clawed frog, Xenopus laevis. To test the toxic effects, frog embryo teratogenesis assays using Xenopus were performed. Embryos were exposed to various concentrations of tebuconazole($0-100\;{\mu}M$). $LC_{100}$ for tebuconazole was $100\;{\mu}M$, and the $LC_{50}$ determined by probit analysis was $82.35\;{\mu}M$. The exposure to tebuconazole concentrations ${\geq}40\;{\mu}M$ resulted in 11 different types of severe external malformations including gut dysplasia. Histological examinations revealed various dysplasia in the eye, heart, liver, intestine, somatic muscle, and in the pronephric ducts. The tissue-specific toxic effects were investigated with an animal cap assay. Blood cells are generally induced at a high frequency by the combination of mSCF and activin A, however, the induction of blood cells was strongly inhibited by the addition of tebuconazole. Electron micrographs of tested embryos showed many of multivesicular bodies and dysplasia of photo-receptive cell, however, the somatic muscle degeneration was not severe. The gene expression of cultivated animal cap explants was investigated by reverse transcriptase-polymerase chain reaction and revealed that expression of the blood-specific marker, $\beta$ globin II and muscle-specific marker, muscle actin were more strongly inhibited than the neural-specific marker, XEn2.