• Toxicological Research
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• 제22권1호
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• pp.39-45
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• 2006

As the antioxidant and free radical scavenger, glutathione (GSH) participates in the preservation of cellular redox status and defense against reactive oxygen species and xenobiotics. Glutamate-cysteine ligase (GCL; also known as ${\gamma}$-glutamylcysteine synthetase, EC 6.3.2.2) is the rate limiting enzyme in GSH synthesis. In the present study, the accurate method for determination of GCL activity in crude liver extracts was developed by measuring both ${\gamma}$-glutamylcysteine and GSH from cysteine in the presence of glutamate, glycine and an ATP-generating system. We added glycine to promote the conversion of ${\gamma}$-glutamylcysteine to GSH, and to minimize the possibility of ${\gamma}$-glutamylcysteine metabolism to cysteine and oxoproline by ${\gamma}$-glutamylcyclotransferase. We established optimal conditions and substrate concentrations for the enzyme assay, and verified that inhibition of GCL by GSH did not interfere with this assay. Therefore, this assay of hepatic GCL under optimal conditions could provide a more accurate measurement of this enzyme activity in the crude liver extracts.

• Toxicological Research
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• 제16권3호
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• pp.229-238
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• 2000

The purpose of reproductive toxicity studies is to evaluate all effects resulting from paternal or maternal exposure that interfere with conception, development, birth, and maturation of offspring. In 1966, the US Food and Drug Administration (US FDA) published guidelines for a three-segment study for drug testing to examine adverse effects on fertility and pregnancy. Three segments were proposed: Segment I, Study of Fertility and General Reproductive Performance, to provide information on breeding, fertility, nidation, parturition, neonatal effects and lactation: Segment II, Teratological study, to provide information on embryo toxicity and teratogenicity: and Segment III. perinatal and Postnatal Study, to provide information on late fetal development, labour and delivery, neonatal viability, and growth and lactation. The classic guideline is still used to this day with only monor modification throughout the world. In the present review, the principles and methods of reproductive toxicity studies are discussed with special attention given to scientific issues.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 춘계학술대회 논문집
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• pp.68-69
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• 2003

Tributyltin (TBT) used world-wide in antifouling paints for ships is a widespread environmental pollutant and cause reproductive organs atrophy in rodents. At low doses, antiproliferative modes of action have been shown to be involved, whereas at higher doses apoptosis seems to be the mechanism of toxicity in reproductive organs by TBT. (omitted)

• Toxicological Research
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• 제19권4호
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• pp.259-266
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• 2003

Although 'Cinnamon' has been widely used for the food and biophamacy in the world, it's toxicity was not screened completely. Major component of 'cinnamon' is CB-OH and CB-PH. CB-PH has been reported to have antimutagenic effect. To investigate the toxicity of 2-o-Benzoylcinnama-Idehyde (CB-PH), repeated dose (4 weeks) oral toxicity test performed in SD rats. Results of repeated dose oral toxicity tests for 4 weeks (CB-PH; 500, 1000, 2000 mg/kg/day) suggested that the CB-PH treated group showed no significant toxicological findings with body weights, organ weights, hematological and histopathological findings. Therefore, these data indicated that the maximum tolerated dose of CB-PH was 2000 mg above/kg/day in the rats.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.89-90
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• 2001

Kimchi is a traditional fermented vegetable food in Korea. There are about 187 varieties of Kimchi, depending on the ingredients and processing methods used, which are different in microbiological, nutritional, and biochemical characteristics. Much attention for Kimchi has been focused on health and life extension. Kimchi is fermented by the microorganisms which are originally present in the raw vegetable substances.(omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.123-124
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• 2001

DNA mutations undoubtedly contribute to the onset of some life style-related diseases including cancer. Rapid and reliable methods to detect DNA mutations and to isolate mutants should have a great impact on this field. Activated inflammatory leukocytes are considered to play some important roles in carcinogenesis by generating reactive oxygen species (ROS). The purpose of the present study is to examine the relationship between leukocyte activation by TPA and mutagenesis.(omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.126-126
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• 2001

Peroxynitrite (ONOO$^{-}$) is one of cytotoxic species produced by the reaction between superoxide(ㆍ $O_2$$^{-}$) and nitric oxide (NO). The aim of this study was to characterize ONOO$^{-}$ scavenging constituents from herbs. Methanolic extract derived from one hundred fifty nine herbs were screened out for their ONOO$^{-}$ scavenging activities. It was investigated that about 33 herbs was excellent scavengers of ONOO$^{-}$. The extracts exhibited dose-dependent ONOO$^{-}$ scavenging activities.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.15-16
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• 2001

GCP is a novel functional food obtained from the extracts of soybean isoflavone fermented with basidiomycetes mycelia. The enzyme reaction makes GCP containing high concentration of isoflavone aglycons, particularly for genistein and high content of polysaccharides. GCP exerts its anti-tumor activities by anti-angiogenesis and induction of apoptosis in cancer tissues and by enhancement of immune responses in immune system.(omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.19-19
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• 2001

Pomegranate (Punica granatum) is one of the worlds most ancient fruits, and also one of the most botanically isolated, comprising a single family (Punicae) with its rare relative, Punica protopunica, a species limited in occurrence to the island of Socotra off the coast of Yemen. Pomegranate, though, is extremely well known, flourishes in many parts of the world, is traditionally prized for its medicinal properties and widely regarded as Symbol: of fecundity, longevity, spirituality and Medicine.(omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.43-44
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• 2001

The increasing evidence for the involvement of food borne HAs in the aetiology of human cancer has stimulated intense efforts to identify dietary constituents which protect against these compounds. About 280 articles on this topic have been published in the last 20 years, most of them were antimutagenicity studies with indicator cells that require addition of exogenous activation mix. The experimental models do not adequately reflect protective mechanisms that are active in vivo and may give misleading results.(omitted)