• BMB Reports
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• v.30 no.3
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• pp.194-199
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• 1997

Previous studies have shown that the HD3 human enterocytic differentiated colon carcinoma cell lines having low $PKC{\beta}$ activity did not respond to diacylglycerol and basic FGF by growth and by activation of pp57 MAP kinase, but undifferentiated cell lines exhibiting high $PKC{\beta}$ activity did. To confirm a role of $PKC{\beta}$ in colonocyte mitogenesis, derivatives of HD3 cell line that stably overexpress a full-length of cDNA encoding the ${\beta}_1$ isoform of human PKC were generated. The abundance and activity of $PKC{\beta}$ in two of the these cell lines, PKC3 and PKC8 were much higher than those in the C1 control cell line that carries the vector lacking the $PKC{\beta}_1\;cDNA$ insert. Following exposure to diacylglycerol or basic FGF, proliferation of PKC3 and PKC8 cells increased about 50%; but this effect was not seen with the control C1 cells. Also, in contrast to the control cells, the $PKC{\beta}_1-overproducing$ cells displayed activation of pp57 MAP kinase when treated with diacylglycerol and basic FGF as undifferentiated cell lines did. These results provide direct evidence that $PKC{\beta}_1$ which plays a key role in mitogenic responses of colon carcinoma cells to diacylglycerol and basic FGF is down-regulated in enterocytic differentiation of colon cells.

• Preventive Nutrition and Food Science
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• v.10 no.2
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• pp.161-166
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• 2005

We investigated the effect of pycnogenol (PYC) supplementation on retarding the immune dysfunction of CS7BL/6 mice after murine AIDS (MAIDS) development. Dysfunction of T and B cell mitogenesis from primary cultured splenocytes has been observed with retrovirus infection and PYC supplementation partially recovered the dysfunction of T and B cells. There was an abnormal shift of cytokine pattern with retrovirns infection, which was designated by the decreased secretion of Th1 cytokines and increased secretion of Th2 cytokines. PYC supplementation increased IL-2 and $IFN-\gamma$ secretion and decreased IL-4, IL-6, and $TNF-\alpha$ secretion, but it was not sufficient enough to maintain the normal level of these cytokines. Hepatic vitamin E level was significantly decreased by retrovirns infection, in accordance with increased hepatic lipid peroxidation level, whereas PYC supplementation normalized the hepatic level of vitamin E and lipid peroxidation. This study suggests that PYC supplementation may partially help retard the incidence of symptoms during MAIDS.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.107-108
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• 2003

The epidermal growth factor (EGF) is an important signaling ligand for the mitogenesis of many cells. The EGF receptors use signaling molecule multicomplexes and dynamic protein networks for the transmission and amplification of the signals as well as for the regulation of the cellular responses. EGF signaling has been reported to be enhanced in various tumors by the overexpressed EGF receptor and/or the mediators such as phospholipase C-$\gamma$1(PLC$\gamma$1). (omitted)

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.193-193
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• 1996

Endothelin-1, which is a peptide originally isolated from cultured porcine aortic cell, has been found to play a crucial role in potentiating the vasoconstriction mitogenesis, and chemotaxis. In the present study, we examined the level of endothelin-1 in the brain, spinal cord and blood from rat with experimental allergic encephalomyelitis(EAE). At the peak stage of EAE(grade 3), endothelin-1 level in the spinal cord of rat with EAE increased two folds as compared with that of sham-treated rats, and subsequently decreased to the level of control at the recovery stage. In the endothelin-1 immunocytochemistry, endothelin-1 immunopositive cells and ED-1, macrophage marker immunopositive cells observed in the spinal cord of peak stage(grade 3). These Findings suggest that endothelin-1 play the important role in progression of EAE.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.288.3-289
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• 2003

Sphingolipid species are important second messengers due to their role in the mitogenesis, differentiation and apoptosis. We developed a new column liquid chromatography-triple quadrupole tandem mass spectrometry (LC-MS/MS) in combination with multiple reaction monitoring (MRM) method for the rapid, simultaneous and quantitative determination of unambiguous detecting sphingolipids in cell culture of human cancer cells (HL-60). (omitted)

• Journal of Aquaculture
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• v.13 no.4
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• pp.359-362
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• 2000

Mitotic gynogenesis was induced in the far eastern catfish, Silurus asotus using UV-irradiated heterospecific sperm and cold shock treatment. Eggs were activated with the sperm of mud loach, Misgurnus mizolepis which has been irradiated with UV at dose of 9,000 ergs/$mm^2$. To determine the optimum duration required to prevent the first cleavage, a cold shock at 4$^{\circ}C$ with duration of 20, 30 or 40 min was applied to the eggs 50 min after activation. To induce diploidization of mitogenesis, the most effective protocol was to apply cold shock to 50-min old (after activation) eggs at 4$^{\Circ}C$ for 30min.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.42-47
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• 1999

Phorbol ester, growth factors activities are mediated by unclear transcription factors, the c-Fos and c-Jun, which can regulate transcriptional activation through specific DNA sites and by forming the transcription factor AP-l, which usually mediates cell proliferation and differentiation signals. We explored effects of Pini Folium extract (API-l) on AP-l activity. Western blot analysis confirmed that API-l decreased levels of c-Fos or c-Jun protein induced by the tumor promoter Phorbol 12-myristate 13-acetate (PMA; 200 nM). Transient transfection assays with a c-fos promoter reporter construct showed that API-l decreased transcription activity by ore than 50~60%. However, treatment of API-l activity studied further. The main substances were fractionated into dichloromethane layer. Futhermore, API-l extract repressed the [$^3H$]-thymidine uptake in C6 glioma cells, indicating that this extract could be included in a new type of modulator in the mitogenesis.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.337.2-337.2
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• 2002

Conjugated linoleic acid (CLA) is a potent inhibitor of mammary carcinogenesis. Cancer cells produce various angiogenic factors which stimulate host vascular endothelial cell mitogenesis and chemotaxis for their growth and metastasis. Basic fibroblast growth factor (bFGF) is a potent angiogenic factor that is expressed in many tumors. In this study. we found that CLA decreased bFGF-induced endothelial cell proliferation and DNA synthesis in a dose-dependent manner. However, CLA did not inhibit endothelial cell migration. Furthermore CLA showed a potent inhibitory effect on embryonic vasculogenesis and bF GF-induced angiogenesis in vivo. Collectively. these results suggest that CLA selectively inhibis the active proliferating endothelial edll induced by bFGF. which may explain its anti-carcinogenix properties in vivo.

• Toxicological Research
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• v.14 no.2
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• pp.163-169
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• 1998

Fluoride (F), over a narrow concentration range, increases bone formation. Aluminum (Ai) too is biphasic in its action on bone, being mitogenic at very low levels and inhibitory at higher levels. Both F and Al are present in finished drinking water where the chemical interaction of these two agents is well characterized. F and AI, given individually, accumulate preferentially in bone. In addition. in vivo studies have shown that F causes the co-accumulation of Al in bone. Thus, it was necessary to determine the interactive effect of these two agents on bone mitogenesis. Calvaria were obtained from neonatal CD-1 mice and cultured with various concentrations of F (0.05~19 ppm) as NaF, Al (2 ppb~2 ppm) as $AlCl_3$ , or F and Al for 3 days at $37^{\circ}C$ on a rotating roller drum. Alkaline phosphatase activity in calvaria and $\beta$-glucuronidase activity in culture medium were determined as a measures of bone turnover. Alkaline phosphatase activity in calvaria was significantly increased by F (0.05~2 ppm) treatment and $\beta$-glucuronidase activity was slightly increased in the culture medium of calvaria treated with 0.3 ppm Al. The combination of 19 ppm F and 0.3 ppm Al increased alkaline phosphatase activity in calvaria, but did not affect $\beta$-glucuronidase activity, suggesting the interactive effect of fluoride and aluminum on bone turnover.

• Natural Product Sciences
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• v.16 no.4
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• pp.291-294
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• 2010

In obesity, adipocytes undergo abnormal growth characterized by increased cell numbers and differentiation. Thus, inhibition of mitogenesis of preadipocytes and their differentiation to adipocytes would be beneficial for the prevention and progression of obesity. In the present study, we attempted to evaluate antiadipogenic activity of adlay (Coix seed, the seed of Coix lacryma-jobi L. var. ma-yuen Stapf) employing preadipocytes cell line, 3T3-L1 as an in vitro assay system. Because several varieties of adlay are in use in Korea, anti-adipogenic activity of three varieties of adlay such as Sang-Gang, Jo-Hyun and Yulmu-Ilho was evaluated. All the three varieties of adlay showed significant inhibitory activity on adipocyte differentiation as assessed by measuring fat accumulation using Oil Red O staining. Adlay, however, showed little effects on adipocyte proliferation. Further studies with interval treatment demonstrated that adlay exerted inhibitory activity on adipocyte differentiation via acting on early stage of adipogenesis. Taken together, adlay might be useful in the prevention of obesity.