• Title/Summary/Keyword: environmental induction

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Induction of Apoptosis by Aloe Vera Extract in Human Hepatocellular Carcinoma HepG2 Cells (알로에 베라 추출물에 의한 사람 간암 세포주 HepG2의 Apoptosis 유도)

  • Kim, Il-Rang;Kwon, Hoon-Jeong
    • Toxicological Research
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    • v.22 no.4
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    • pp.329-332
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    • 2006
  • Ethanolic extract of Aloe vera (Aloe barbadensis Miller) was examined for the cellular toxicity on HepG2 human hepatocellular carcinoma cells. Treatment with Aloe vera extract resulted in DNA fragmentation but not LDH release, suggesting an apoptosis instead of necrosis. Aloe vera induced cytotoxicity was mediated by decrease in ATP levels, whereas GSH depletion, increase in intracellular $Ca^{2+}$, or activation of caspase-3/7 could not be observed with statistical significance. No activation of caspase-3/7 suggests the possibility of caspase-independent apoptosis. Taken together, our results show that Aloe vera extract induce HepG2 apoptosis by ATP depletion-related impairment of mitochondria, which is caspase-independent.

Measurement of the Torque for Driving Cam Shaft in Real Engine Environments (실 엔진 상태 캠 구동 토크 측정)

  • Kang, Seung-Pyo;Kauh, S.Ken;Ha, Kyoung-Pyo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.31 no.3 s.258
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    • pp.242-247
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    • 2007
  • Energy savings and environmental protection policies have been the general trend in the engine design. The friction power loss associated with the cam mechanism has become important. But it is difficult to measure the torque of rotating valvetrain in real engine environment because most of conventional torque meters are axial type. The objective of this paper is to develop new equipment which can be installed in a rotating camshaft. It uses strain gages to measure the elastic deformation of torque sensor which replaces the cam sprocket. It includes telemetry to transmit torque data via Bluetooth and induction power system to provide adequate power to rotating torque meter. The developed torque meter has good linearity and thermostability. It was installed in a real engine, and successfully measured the valvetrain torque.

SUPPRESSION OF HUMAN PROSTATE CANCER CELL GROWTH BY $\beta$-LAPACHONE VIA INHIBITION OF pRB PHOSPHORYLATION AND INDUCTION OF Cdk INHIBITOR $p21^{WAF1/CIP1}$

  • Park, Yung-Hyun;Kang, Ho-Sung;Yoo, Mi-Ae
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.150-150
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    • 2001
  • $\beta$ -lapachone, the product of a tree (Tabebuia avellanedae) from South America, is known to exhibit various pharmacologic properties, the mechanisms of which are poorly understood. The aim of the present study was to further elucidate the possible mechanisms by which $\beta$-lapachone exerts its anti-proliferative action in cultured human prostate cancer cells.(omitted)

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EFFECT OF BETAINE OR TAURINE PRETREATMENT ON LIPOPOLYSACCHARIDE-INDUCED HEPATOTOXICITY IN RATS

  • Kim, Sang K.;Young S. Jung;Yu R. Chae;Kim, Young C.
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.165-165
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    • 2001
  • The effects of betaine or taurine on hepatotoxicity induced by lipopolysaccharide (LPS) were examined in adult male SD rats. Rats were provided with drinking water containing either 1 % betaine or taurine for 2 weeks prior to challenge with LPS (5 mg/kg, iv). Supplement of betaine or taurine protected the animals from induction of LPS hepatotoxicity as measured by changes in aspartate aminotrassferase (AST), alanine aminotransferase (ALT) activities and total bilirubin levels in serum, and hepatic glutathione contents.(omitted)

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GCP (GENISTEIN CONCENTRATED POLYSACCHARIDE): A SOYBEAN ISOFLAVONE DIETARY SUPPLEMENT FERMENTED BY BASIDIOMYCETES WITH ANTI CARCINOGENIC ACTIVITIES: THEIR MOLECULAR MECHANISMS AND CHEMOPREVENTIVE POTENTIAL

  • Lan Yuan;Takehito Miura;Mayumi Yoshida;Chihiro Wagatsuma;Hajime Fujii;Tomomi Mukoda;Sun, Bu-Xiang;Kenichi Kosuna
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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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)

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EFFECTS OF THE SOY ISOFLAVONE GENISTEIN ON COX-2 EXPRESSION AND ACTIVATION OF ERKl/2 INDUCED BY PHORBOL ESTER AND TNF-$\alpha$ IN HUMAN BREAST EPITHELIAL CELL LINE (MCF10A)

  • Chung, Myung-Hoon;Kim, Jung-Hwan;Lee, Seung-Sei;Keum, Joo-Seob;Surh, Young-Joon
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.135-136
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    • 2001
  • Genistein has been shown to exert propective effects against chemically induced carcinogenesis in animals as well as malignant transformation in cultured cells, but molecular mechanisms of its chemopreventive or chemoprotective activities remain largely unresolved. In the present sturdy, we have investigated the effects of genistein on induction of cyclooxygenase-2 (COX-2) that plays an important role in the pathophysiology of carcinogenesis as well as in cellular response to inflammatory stimuli.(omitted)

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INHIBITORY EFFECTS OF RED GINSENG EXTRACT ON PRENEOPLASTIC NODULE FORMATION IN THE RAT LIVER OBSERVED BY RAPID BIOASSAY OF CARCINOGENESIS

  • Kim, Yun-Bae;Lee, Yong-Soon
    • Toxicological Research
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    • v.4 no.2
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    • pp.159-179
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    • 1988
  • This study was carried out to investigate the inhibitory effects of red ginseng extract on preneoplastic nodule formation in the rat liver using a rapid bioassay of hepatocarcinogenesis. Wistar male rats in test groups were fed diets containing 3.0, 0.3 or 003% of red genseng extract for 6 weeks after 2 week of dosing with diethylnitrosamine (DEAN, 200 mg/kg B.W., I.P.) or saline solution. The rats in the control groups were treated with DENA or saline alone. Three weeks after the beginning of the experiment, the two-thirds partial hepatectomy was performed on all animals. The inhibitory effects were investigated by measuring the number, total area and size of hyperplastic nodules enhanced by the 2/3 partial hepatectomy following induction with DENA. The results obtained were summarized as follows: 1. In general, the body weight gains of the rats fed diets containing red ginseng extract were higher than those of other groups.

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CHEMOPREVENTIVE EFFECTS IN MOUSE SKIN CARCINOGENESIS AND INDUCTION OF APOPTOSIS IN HUMAN PROMYELOCYTIC LEUKEMIA(HL-60) CELLS BY XANTHORRHIZOL

  • Kim, Heui-og;Chung, Won-Yoon;Park, Min-Ah;Kim, Mi-Jeong;Park, Jae-Hee;Park, Kwang-Kyun
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.141-142
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    • 2001
  • Curcuma xanthorrhiza Roxb(Zingiberaceae) has been traditionally used in Indonesia for dietry and medicinal purposes. Xanthorrhizol is a sesquiterpenoid isolated from C. xanthorrhiza that has been known to possess anti-inflammatory and anticarcinogenic defects.(omitted)

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CELL CYCLE ARREST AND INDUCTION OF APOPTOSIS BY NOVEL CDK INHIBITOR IS ASSOCIATED WITH $p161^{NK4A}$ UP-REGULATION IN HUMAN PROMYELOCYTIC LEUKEMIA CELLS

  • Park, Bu-Young;Kim, Min-Kyoung;Kim, Hak-Yup;Cho, Youl-Hee;Lee, Chul-Hoon
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.151-152
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    • 2001
  • MCS-5A, novel Cdk inhibitor, has been reported that it has exerted cell cycle arrest action and apoptotic effect to the human promyelocytic leukemias cell. The purpose of this study is to verify these effects of MCS-5A on human promyelocytic leukemia (HL-60) cells and to clarify the action of mechanism on MCS-5A-inducing apoptosis.(omitted)

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Evaluation of Adverse Drug Properties with Cryopreserved Human Hepatocytes and the Integrated Discrete Multiple Organ Co-culture (IdMOCTM) System

  • Li, Albert P.
    • Toxicological Research
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    • v.31 no.2
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    • pp.137-149
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    • 2015
  • Human hepatocytes, with complete hepatic metabolizing enzymes, transporters and cofactors, represent the gold standard for in vitro evaluation of drug metabolism, drug-drug interactions, and hepatotoxicity. Successful cryopreservation of human hepatocytes enables this experimental system to be used routinely. The use of human hepatocytes to evaluate two major adverse drug properties: drug-drug interactions and hepatotoxicity, are summarized in this review. The application of human hepatocytes in metabolism-based drug-drug interaction includes metabolite profiling, pathway identification, P450 inhibition, P450 induction, and uptake and efflux transporter inhibition. The application of human hepatocytes in toxicity evaluation includes in vitro hepatotoxicity and metabolism-based drug toxicity determination. A novel system, the Integrated Discrete Multiple Organ Co-culture (IdMOC) which allows the evaluation of nonhepatic toxicity in the presence of hepatic metabolism, is described.