• KSBB Journal
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• v.19 no.2
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• pp.118-124
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• 2004

Melanocytes synthesize melanin within discrete organelle termed melanosomes which are transferred to the surrounding keratinocytes and can be produced in varying sizes, numbers and densities. Skin whitening products have become increasingly popular in the past few years. The most successful natural skin whitening agents are: Arbutin, Vitamin C, Kojic acid, Mulberry, which are all tyrosinase inhibitors. In this work, melanoston, a melanogenesis inhibitor isolated from yeast was studied to understand its mechanism of melanogenesis inhibition. It was found that melanoston was not a tyrosinase inhibitor, while when melanoston was applied to the B16 melanoma cell culture media, the intracellular tyrosinase activity was decreased by more than 30％, When B16 melanoma was stimulated with ${\alpha}$-MSH, cell morphololgy was dramatically changed to have lots of dendrites on the cell membrane surface. On the other hand, B16 was treated with ${\alpha}$-MSH and melanoston, simultaneously, the change of cell morphology was not so great. This inhibition effect of melanoston was found to be related to the inhibition of intracellular activation and transportation of tyrosinase, which was observed by immunostaining of B16 melanoma using anti-tyrosinase antibody. From these results, melanoston was regarded as an inhibitor to the differentiation of melanoma cells.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1029-1034
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• 2000

A suitable method of sample treatments to minimize the analytical interferences was presented in order to determine bisphenols [bisphenol F (BPF), bisphenol A (BPA), bisphenol F diglycidyl ether (BFDGE), and bisphenol A diglycidyl ether (BADGE)] in various canned beverages coated with epoxy resin by the reversephase high performance liquid chromatography (RP-HPLC) equipped with a fluorescence detector and the gas chromatography with mass selective detection. The recovery test of bisphenols was performed using 1, 5, and 10 ${\mu}g/L$ bisphenols spiked beverages with the combined technique of the solid-phase extraction (SPE) and the liquid-phase extraction (LPE). Both BPA and BADGE showed quite adequate resolutions in HPLC-chromatograms. The recoveries of BPA obtained by LPE with diethyl ether were higher than those obtaind with methylene chloride on coffee, shikhye and fruit juice. For cola and tea, the recoveries of BPA obtaind by SPE were higher than those by LPE with diethyl ether. The recoveries of BADGE were less than those of BPA for all beverage samples treated by either SPE or LPE method. In survey of bisphenols for eighteen commercial canned beverage samples, BPA contents of coffee, cola, tea, shikhye, and fruit juice were in the range of $1.3{\sim}11.6,\;0.5{\sim}0.9,\;1.0{\sim}1.3,\;2.4{\sim}7.9$, and $3.0{\sim}3.4\;{\mu}g/L$, respectively, but there was no detection of BPA in beer sample.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.1 s.49
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• pp.25-33
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• 2005

Melanocytes synthesize melanin within discrete organelle termed melanosomes which are transferred to the surrounding keratinocytes and can be produced in varying sizes, numbers and densities. Skin whitening products have become increasingly popular in the past few years. The most successful natural skin whitening agents are: arbutin, vitamin C, kojic acid, and mulberry, which are all tyrosinase inhibitors. In this work, melanoston, a melanogenesis inhibitor isolated from yeast was studied to understand its mechanism of melanogenesis inhibition. It was found that melanoston was not a tyrosinase inhibitor, while when melanoston was applied to the B16 melanoma cell culture media, the intracellular tyrosinase activity was decreased by more than $30\%$. When B16 melanoma was stimulated with $\alpha$-MSH, cell morphololgy was dramatically changed to have lots of dendrites on the cell membrane surface. On the other hand, B16 was treated with $\alpha$-MSH and melanoston, simultaneously, the change of cell morphologv was not so great. This inhibitory effect of melanoston was found to be related to the inhibition of intracellar activation and transportation of tyrosinase, which was observed by irmmunostaining of B16 melanoma using anti-tyrosinase antibody. From these results, melanoston was regarded as an inhibitor to the differentiation of melanoma cells.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.477-484
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• 2019

Several types of scavenger receptors, including the Collectin-Placenta 1 (CL-P1) receptorthat is present in mammals, are molecules that are expressed on the surfaces of endothelial cells, macrophages and smooth muscle cells. These molecules are cell surface glycoproteins that can be conjugated to oxidized low density lipoprotein (oxLDL). Among these molecules, the effect of quercetin on CL-P1 activation has been confirmed. Quercetin is known as an antioxidant that stops oxidation because it acts to remove free radicals that are responsible for the oxidation reaction. In this study, fragments from the transcription start site of the mouse CL-P1 gene promoter to the -500th base were cloned using DNA polymerase. These fragments were then introduced into macrophage like RAW264.7 cells and fibroblast-like NIH3T3 cells to study the effect of quercetin on the CL-P1 gene expression. As a result, we found that bases ranging from -250 to -350 in the anterior part where gene expression starts are important for producing CL-P1 protein. Among them, the DNA mutation experiments we performed confirmed that the E2F binding sites are critical for producing the CL-P1 protein? In addition, when quercetin was added to the RAW264.7 culture medium, which was a culture of adherent cells, observedthe phenomenon of the cells falling off from the surface of the culture container.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.5
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• pp.712-720
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• 2022

In this study, we evaluated the production and photoreactivity of CDOM of two polar phytoplanktons - Phaeocystis antarctica and Phaeocystis pouchetii, in order to find out UV effects on phytoplanktons. In visible region, CDOM in media of both phytoplanktons under UV-R decreased during 48hrs incubation period. However, in UV region CDOM decreased 30 % in the media of P. antarctica, but increased 10% in media of P. pouchetii, compared to CDOM concentrations of control after 48 hr incubation. This result indicates that biota in polar environment would not well protected from UV-R harmful effect when P. antarctica is dominant because of loss of CDOM, but when P. pouchetii is dominant species, production of UV absorbing organic matter could play more efficiently for UV screening for marine biota. Also we confirmed that FDOM of humic substance (C-peak) produced by these phtoplanktons under UV-R stress were well matched with fluorescence characteristics of the UV-protecting compound, MAAs. This finding shows that Phaeocystis pouchetti with low photoreactivity would contribute to DOM pool of polar marine environment under stratification by global warming.

• Korean Journal of Animal Reproduction
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• v.24 no.4
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• pp.429-437
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• 2000

This study investigated the successful introduction of genes of erythropoietin (EPO) and enhanced green fluorescent protein (EGFP) in bovine embryos following nuclear transfer of bovine fetal fibroblasts (bFF), which were transfected by retrovirus vector system. Non-starved bFF were, transferred into perivitelline space of enucleated oocytes. The bFF-oocyte units were accomplished by cell to cell fusion and activated with calcium inophore and 6-dimethylaminopurine. Reconstructed embryos were co-cultured with bovine oviduct epithelial cells in CRlaa medium for 8 days. Out of 187 (EPO) and 210 (EGFP) bovine eggs reconstructed by nuclear transfer, 149 (EPO : 80.0%) and 158 (EGFP : 75.2%) embryos were cleaved, and among them 36 (EPO : 24.2%) and 35 (EGFP : 22.2%) embryos developed to the blastocyst stage. Of these blastocysts, 100% integration of EPO gene in 36 embryos was determined by PCR, and 100% expression of EGFP gene in 35 embryos was observed under the fluorescent microscope. This result indicates that bovine oocytes reconstructed by nuclear transfer of transfected bFF can successfully develop to the blastocyst stage. Furthermore, this novel procedure may be presumably an attractive method efficiently to produce the transgenic cattles.

• Korean Journal of Animal Reproduction
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• v.25 no.4
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• pp.305-315
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• 2001

In this study, the production of transgenic embryo was attempted by microinjection or round spermatid cultured with foreign DNA. At first, the expression of haploid spermatids specific gene, mTP1 in mouse and hPrm2 in hamster spermatids were investigated by RT-PCR method in testes of young mice and hamster testis. The specific gene expression first appeared at 18 days post partum (dpp) in mice spermatid and 20 dpp in hamster spermatid. Therefore, the round spermatids isolated from 17 dpp mice and 19 dpp hamster were used for the introduction of foreign EGFP gene into haploid round spermatids. For the introduction of EGFP gene haploid round spermatids suspended in medium including EGFP gene were treated with a different electric field strength at 0.11, 0.18 and 0.44 ㎸/cm. After electrical stimulation, viability of testicular sperm cells and 67.6%, 66.4% and 49.9%, in mice and 62.6%, 57.9% and 27% in hamster, respectively. These values were significantly lower than those of non-treated control groups 80.5% in mouse and 69.1% in hamster After 72 hrs culture, the highest expression rate of EGFP gene, 28.5% in mice and 32.1% in hamster were obtained from tile spermatogenic cells electroporated by the field strength or 0.18 ㎸/cm. Then, the ability of fertilization and embryonic development of haploid spermatids transfected with foreign EGFP gene were estimated by the microinjection of spermatids into hamster oocytes. The Irate pronuclear formation rate (77.5%) was lower than non-treated control (80%), and the cleavage rate of the treated group (58.8%) was lower than control (65%). To prove the foreign EGFP integration in hamster embryos, 2-cell stage hamster embryos were subjected to the observation under the fluorescence microscope, and the PCR analysis. As a result, about 44% of 2-cell embryos were showed the integration of EFGP gene into their genome. Therefore, These results suggest the possibility to produce transgenic hamsters by microinjection of haploid spermatid transfected with foreign DNA.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.519-526
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• 2023

Present study explored immunostimulatory effects of Astragalus membranaceus and Zanthoxylum schinifolium 1:1 (w:w) mixture (AZM-1:1) in Raw264.7 cells, mouse macrophage derived cells. Treatment with 100-400 ㎍/mL of AZM-1:1 in Raw264.7 cells significantly increased nitric oxide production in parallel with inducible nitric oxide synthase mRNA expression without affecting cytotoxicity. In addition, AZM-1:1 dose-dependently increased prostaglandin E₂ production in conditioned medium along with cyclooxygenase-2 mRNA induction. Moreover, AZM-1:1 induces the transcription of tumor necrosis factor-α, interleukin-1β, interleukin-6, and monocyte chemoattractant protein-1. Immunoblot analyses revealed that AZM-1:1 significantly increased the phosphorylation of mitogen-activated protein kinases, provoked phosphorylation-mediated degradation of inhibitory-κBα, and phosphorylated p65. Furthermore, treatment with AZM-1:1 promoted phagocytosis of Escherichia coli particle labeled with green fluorescence. Taken together, AZM-1:1 may be a promising nutraceutical for stimulation the innate immune system, including macrophages.

• Radiation Oncology Journal
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• v.12 no.1
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• pp.27-31
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• 1994

There are a number of reports suggesting that there may be a correlation between the clinical response to radiotherapy in various tumors and the clonogenic survival of cell lines derived from these tumors following exposure to 2 Gy(SF2). Authors conducted this study to determine SF2 for cells in primary culture from surgical specimens. The tumor tissues with squamous cell carcinoma of uterine cervix and head and neck were obtained. The tumor tissues were disaggregated to single cells by incubating with collagenase type w for 2 hours with constant stirring. Single cell suspensions were inoculated in four 24-well plates precoated with cell adhesive matrix. After 24 hours of incubation at 37$ ^{\circ}C $, rows of four wells were then irradiated, consisting of control set and five other sets each receiving doses of 1,2,3,4, and 6 Gy. After incubation for a total of 13 days, the cultures were stained with crystal violet and survival at each dose was determined by quantitative image analysis system, To determine whether cell growth was of epithelial origin, immunocytochemical staining with a mixture of cytokeratin and epithelial monoclonal antibodies were performed on cell cultures. During the period of this study, we received 5 squamous cell carcinoma specimens of head and neck and 20 of uterine cervical carcinoma. Of these, 15 yielded enough cells for radiosensitivity testing. This resulted an overall success rate of 60$ \% $. The mean SF2 value for 15 tumours was 0.55$\pm$0.17 ranging from 0.20 to 0.79. These results indicate that there is a broad range of sensitivities to radiation in same histologic type. So with a large patient population, we plan to determine whether a different SF2 value is associated with tumours that are controlled with radiotherapy than those that are not.

• Clinical and Experimental Pediatrics
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• v.49 no.9
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• pp.977-982
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• 2006

Purpose : There has been an increasing amount of literature concerning the association between Mycoplasma pneumoniae and asthma pathogenesis. Interleukin(IL)-6 stimulates the differentiation of monocytes, and can promote Th2 differentiation and simultaneously inhibit Th1 polarization. IL-8 is a potent chemoattractant and, it has been suggested, has a role in asthma pathogenesis. Nitric oxide (NO) synthesized by airway epithelium may be important in the regulation of airway inflammation and reactivity. Vascular endothelial growth factor(VEGF) has been reported to be a mediator of airway remodeling in asthma. We investigated the effects of M. pneumoniae on IL-6, IL-8, NO and VEGF production in human respiratory epithelial cells. Methods : A549 cells were cultured and inoculated with M. pneumoniae at a dose of 20 cfu/cell. After infection, the presence of M. pneumoniae in epithelial cell cultures was monitored by immunofluorescence and confirmed by polymerase chain reaction(PCR) detection. IL-6, IL-8 and VEGF were determined by an enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction. NO was measured using the standard Griess reaction. Results : In A549 cells, M. pneumoniaeinduced IL-6, IL-8, NO and VEGF release in time-dependent manners. It also induced mRNA expression of IL-6, IL-8 and VEGF in similar manners. Conclusion : These observations suggest that M. pneumoniae might have a role in the pathogenesis of the allergic inflammation of bronchial asthma.