• 농약과학회지
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• 제2권3호
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• pp.1-20
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• 1998

Chlorsulfuron, one of sulfonylurea herbicides acts through inhibition of acetolactate syuthase (EC 4.1.3.18; ALS, also known as acetohydroxyacid synthase) in the branched-chain amino acid biosynthesis process. After chlorsulfuron-ALS interaction, many physiological and metabolic disruptions occur in plants. However, it is not clear how this chlorsulfuron-ALS interaction affects those physiological and metabolic processes and how this interaction leads subsequently to plant death. Several researchers suggested that the death of chlorsulfuron-treated plants might be due to a shortage of the branched-chain amino acids, an accumulation of toxic metabolites, and/or a depletion of photoassimilates. It remains as a mystery presently, however, if such changes result in the plant death. In this review, we discussed how the chlorsulfuran-ALS interaction leads to physiological and metabolic disruptions in plants.

• The Korean Journal of Physiology and Pharmacology
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• 제7권1호
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• pp.33-37
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• 2003

Oxidative damage to mitochondria is a critical mechanism in necrotic or apoptotic cell death induced by many kinds of toxic chemicals. Thioredoxin (Trx) family proteins are known to play protective roles in organisms under oxidative stress through redox reaction by using reducing equivalents of cysteines at a conserved active site, Cys-X-X-Cys. Whereas biological and physiological properties of Trx1 are well characterized, significance of mitochondrial thioredoxin (Trx2) is not well known. Therefore, we addressed physiological role of Trx2 in PC12 cells under oxidative stress. In PC12 cells, transiently overexpressed Trx2 significantly reduced cell death induced by hydrogen peroxide, whereas mutant Trx2, having serine residues instead of two cysteine residues at the active site did not. In addition, stably expressed Trx2 protected PC12 cells from serum deprivation. These results suggest that Trx2 may play defensive roles in PC12 cells by reducing oxidative stress to mitochondria.

• 동의생리병리학회지
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• 제23권1호
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• pp.199-205
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• 2009

It is unclear whether Fructus ligustri Lucidi (FLL) extract anti-proliferative effect in human glioma cells. The present study was therefore undertaken to examine the effect of FLL on cell viability and to determine the underlying mechanism in A172 human glioma cells. Cell viability and cell death were estimated by MTT assay and trypan blue exclusion assay, respectively. Apoptosis was measured by Annexin-V binding assay and cell cycle analysis. Activation of kinases and caspase-3 was estimated by Western blot analysis. FLL resulted in apoptotic cell death in a dose- and time-dependent manner. FLL-induced cell death was not associated with reactive oxygen species generation. Western blot analysis showed that FLL treatment caused down-regulation of PI3K/Akt pathway, but not ERK. The PI3K/Akt inhibitor LY984002 sensitized the FLL-induced cell death and overexpression of Akt prevented the cell death. FLL induced caspase-3 activation and the FLL-induced cell death was prevented by caspase inhibitors. These findings indicate that FLL results in a caspase-dependent cell death through a P13K/Akt pathway in human glioma cells. These data suggest that FLL may serve as a potential therapeutic agent for malignant human gliomas.

• 약학회지
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• 제45권4호
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• pp.426-430
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• 2001

Cells are eliminated in a variety of physiological settings by apoptosis, a genetically encoded process of cellular suicide. Bak, a member of the Bcl-2 protein family, accelerates apoptosis by an unknown mechanism. We have found a novel cDNA encoding a 101 amino acid protein possessing a Bak-like in our full-length cDNA bank. Bak-like shares the conserved domains BHI and 2 with other proapoptotic proteins but lacks the BH3 domain. Bak-like is expressed in a wide variety of tissues. Like Bak, Bak-like gene product primarily enhances apoptotic cell death following an appropriate stimulus.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.496-497
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• 2008

In this study, we present the computational analysis of cardiac arrhythmias that is the major cause of human sudden cardiac death. First, electric excitation and condution in one dimensional cardiac tissue model is solved and the results on condution block are represented. In two dimensional model, vortex daynamics in cardiac tissue is analyzed to delineate the breakup phenomenon inducing ventricular fibrillation. We also simulated a three dimenional heart model to see the vortex breakup and explained the mechanism in physiological aspect.

• 한국수정란이식학회지
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• 제13권2호
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• pp.179-190
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• 1998

Prolactin (PRL) surge in cycling rats at proestrous afternoon has previously been reported as an inducer of apoptotic cell death of luteal cells. This death-inducing action of PRL seeins unusual, because PRL can he categorized as a cell-survival factor, if other known physiological functions of PRL are taken into account. In this study, the apoptotic action of PRL was assessed in cultured cells prepared from rat luteal tissue and underlying molecular /cellular mechanism of PRL-induced luteolysis was analyzed. The latest crop of corpora lutea (CLs) were enucleated from rat ovaries at 18:00 h on the proestrous day before the next ovulation. Donor rats were pretreated with CB154, a dopamine agonist, in order to he exempted from the endogenous PRL surge. The harvested GLs were dispersed and cultured with or without PRL (2$\mu$g /ml) for 24 or 48 h. An addition of PRL to the culture medium changed the parameters indicative of cell death via apoptosis: a decrease in cell viability (MTT) and an increase in chromatin condensation. Most of the DNA breakdown in nuclei induced by PRL occurred in steroidogenic cells which were identified by 3$\beta$-HSD activity staining, and the number of 3$\beta$-HSD-positivecells were significantly decreased. Interestingly, most of the cells with an apoptotic nucleus adhered to one or more intact and seemingly non-steroidogenic cells. Because the expression of Fas has heen shown to be abundant in murine ovary, and Fas is known to have an exact physiological role in occurrence of apoptotic cell death, the membrane form-Fas ligand (rnFasL) was quantified in the cell lysate. An addition of PRL increased expression of mFasL. Moreover, an addition of concanavalin A (ConA), a T-cell specific activator, in place of PRL, enhanced the apoptotic parameters. Cumulatively, the apoptotic PRL action was addressed to cells unknown than steroidogenic lute~ cells. The most prohable candidate for the direct target cells is Tcells in the luteal tissue that can express mFasL in response to PRL.

• 동의생리병리학회지
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• 제18권2호
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• pp.544-552
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• 2004

In oriental medicine, Radix Polygalae(RP) has been to treat tremors et al. But the mechanism how to decrease tremors was not known. The purpose of this study was to investigate the effect of RP on neurodegenerative disease. We used RP to execute the study of this defense mechanism on dopamine-induced cell death in human SH-SY5Y dopaminergic neuroblastoma cells. MTT assay was used to know the cytotoxicity of dopamine and the defense mechanism. As a result of this experiment, dopamine had cytotoxicity in human SH-SY5Y cells, but when it treated with RP, the cell survival rate increased. This suppressed the cell apoptosis, activation of caspase-3 protease, production of ROS, and repair of membrane potential change. In conclusion, RP has the protective effect on dopamine-induced cell death in human SH-SY5Y dopaminergic neuroblastoma cells, so this could be an effective agent on the neurodegenerative disease like Parkinsonism.

• 동의생리병리학회지
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• 제20권6호
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• pp.1548-1555
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• 2006

Bujeonghangam-tang(BHT) has been used as an anticancer agent in oriental medicine, but the mechanism by which it induces cell death in cancer cells is still unclear. To investigate cell death mechanism by BHT in cancer cells, the activities of apoptosis signaling pathway were tested in human neuroblastoma cell line LAN5. Viability of LAN5 cells was markedly decreased by treatment of the water extract of BHT in a dose-dependent manner. BHT induced cell death was confirmed as apoptosis characterized by chromatin condensation. We tested whether the water extract of BHT affects the anti-apoptotic protein such as Bcl-2 and Bcl-XL, and the pro-apoptotic protein such as Bax. Both Bcl-2 and Bcl-XL were gradually decreased but Bas was increased in a time-dependent manner after the addition of the water extract of BHT. Cleavage of Bid by activation of caspase-8 protease was also observed in LAN-5 cells by the treatment of the water extract of BHT. Taken together, these results suggest that the water extract of BHT exerts anti-cancer effects on human neuroblastoma LAN-5 cells by inducing the apoptotic death via down-regulation of anti-apoptotic proteins such as Bcl-2 and Bcl-XL, up-regulation of pro-apoptotic protein such as Bax, and activation of intrinsic caspase cascades.

• BMB Reports
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• 제38권3호
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• pp.314-319
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• 2005

Adenosine, as a ubiquitous metabolite, mediates many physiological functions via activation of plasma membrane receptors. Mechanisms of most of its physiological roles have been studied extensively, but research on adenosine-induced apoptosis (AIA) has only started recently. In this study we demonstrate that adenosine dose-dependently triggered apoptosis of cultured baby hamster kidney (BHK) cells. Adenosine-induced apoptotic cell death was characterized by DNA laddering, changes in nuclear chromatin morphology and phosphatidylserine staining. Apoptosis was also quantified by flow cytometry. Results suggest the involvement of adenosine $A_1$ and $A_3$ receptors as well as equilibrative nucleoside transporters in apoptosis induced by adenosine. These results indicate a receptor-transporter co-signaling mechanism in AIA in BHK cells. The involvement of $A_1$ and $A_3$ receptors also implies a possible apoptotic pathway mediated by G protein-coupled receptors.

• International Journal of Advanced Culture Technology
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• 제4권4호
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• pp.45-50
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• 2016

This is a humanistic study to trace phenomena logically the comprehensive therapeutic mechanism of the human body which is coded by the smart emotion of the rated signal conveyed by the Rated Sijo. The Gestalt, which is structured in the form of therapeutic metastasis conveyed by sentences, is intended to embody the principle of human response. So, this researcher explored the metastatic structure toward Gestalt of original human being through the passage of foreground and background by ergonomic and chemical structure. In the meantime, this researcher focused on revealing the structure of the field of existence by the symbol system in which the therapeutic mechanism of the human body is embodied. As a result, the basic framework of Gestalt literary therapy, which contributes to the improvement of the Quality of Life metaphorized as a mechanism of the symbol system by the metastasis of literary therapy or the electrical operation of the human body. As a result, the human body as a conductor through literature has turned out to be an original Gestalt structure pursued by literature. In addition, it was analyzed that the human body would accept signals such as emotions and Rated Emotions planted in the sentence, and synapse them into the human physiological psycho analytical symbol system. Therefore, it has been confirmed possibility that human existent environment and trauma are separated from the whole universe can push fully implement therapeutic techniques toward totalization by a combination of literary devices, especially appropriate electric signal combination of the Rated Sijo.