• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.89-92
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• 2001

Aspergillus niger has been used as a host system to express many heterologous proteins. It has various advantages over other expression systems in that it is a small eukaryotic GRAS (Generally Recognized aS Safe) organism with a capacity of secreting large amount of foreign proteins. However, it has been known that the presence of an abundant protease is a limiting factor to express a heterologous protein. The proteases deficient mutants of A. niger were obtained using UV -mutagenesis. A total of 1 ${\times}$ $10^5$ spores were irradiated with 10-20% survival dose of UV, 600J/M2 at 280nm, and the resulting spores were screened on the casein -gelatin plates. Ten putative protease deficient mutants were further analyzed on the starch plates to differentiate the pro from the secretory mutant. An endogenous extracellular enzyme, glucose oxidase, was also examined to confirm that the mutant phenotype was due to the proteases deficiency rather than the mutation in the secretory pathway. The reduced proteolytic activity was measured using SDS-fibrin zymography gel, casein degradation assay, and bio-activity of a supplemented hGM -CSF (human Granulocyte-Macrophage Colony Stimulating Factor). Comparing with the wild type strain, less than 30 % of proteolytic activity was observed in the culture filtrate of the protease deficient mutant (pro -20) without any notable changes in cell growth and secretion.

• Plant Biotechnology Reports
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• 제2권3호
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• pp.199-206
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• 2008

We have developed an efficient system of assessing the ability of a gene silencing cassette to silence transcripts from recalcitrant or poorly studied plant species by using a model plant as a host for the gene of interest. Tobacco plants transgenic for Lachrymatory Factor Synthase (LFS) enzyme activity from onion were first produced by introducing a CaMV 35S-onion-lfs gene construct. These plants were then subjected to a second transformation with an RNAi construct directed against the lfs gene sequence. LFS enzyme activity assay showed that the transgenic plants, containing both the lfs gene and the RNAi construct, had significantly reduced LFS activity. This observation was supported by Western analysis for the LFS protein and further validated by quantitative RT-PCR analysis that demonstrated a significant reduction in the lfs transcript level in the dual transformants. In this work, we have demonstrated that the RNAi construct is a suitable candidate for the development of a non-lachrymatory onion. Our model plant RNAi system has wide-reaching applications for assessment and targeting of plant secondary pathway genes, from poorly studied or recalcitrant plant species, that are important in the pharmacological, food and process industries.

• Natural Product Sciences
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• 제17권1호
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• pp.26-32
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• 2011

Novel tyrosinase inhibitors are important for pigmentation in the skin. Following extraction of tyrosinase inhibitors from edible vegetables or fruits, we found that the Prunus persica flesh extract (PPFE) exhibited potential inhibitory activity for melanogenesis. PPFE showed tyrosinase inhibitory activity in an enzymatic assay and PPFE also significantly inhibited the melanin formation in cultured mouse melan-a cells. Moreover, real-time RT-PCR analysis revealed that the inhibition of melanin production by PPFE was closely related to marked suppression of mRNA expression of tyrosinase and tyrosinase-related protein-1 and -2 (TRP-1 and TRP-2) in melan-a cells. Further investigation found that the modulation of tyrosinase expression by PPFE was associated with the transcriptional regulation of the microphthalmia-associated transcription factor (MITF). PPFE inhibited the promoter activity of MITF and suppressed MITF mRNA expression in melan-a cells. These results indicate that PPFE down-regulates melanogenesis-associated gene expression through MITF-mediated transcriptional regulation and these events might be related to the hypopigmentary effects of PPFE.

• 한국조경학회지
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• 제19권3호
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• pp.87-97
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• 1991

The primary purpose of this study is to investigate factors and variables which have significant effects on user's satisfaction with recreational activities in Daeshin Natural Park, thereby establishing directions of development of urban parks. To test the causal models of this research, the data were gathered by self-administered questionnaires form 627 households in Pusan City which were selected by the multi-stage probability sampling method. The analysis of the data primarily consists of two-phase: The first analysis dealt exploratory factor analysis which identified major factors involved in satisfaction with recreational activities in Daeshin Natural Park and the second analysis tested the fit of the causal models of this research by employing LISREL methodology. The factor analysis identified that three factors are involved in satisfaction with recreational actitives. The three factors of satisfaction with recreational activities are facilities for health and phisical exercise, group recreational activity, maintenance activity. The second phase analysis tested the fit of the causal models for satisfaction with recreational activity to the data and identified statistically significant causal linkage among overall satisfaction with Daeshin Natural Park, other endogenous factors and exogenous variables.

• BMB Reports
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• 제34권1호
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• pp.66-72
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• 2001

To investigate the mechanism of adriamycin (ADM) resistance in the ADM resistant subline PC-14/ADM, we examined the expressions of p-glycoprotein (P-gp), topoisomerase I (Topo I) and II (Topo II), glutathione-S-transferases (GSTs), tissue transglutaminase (t-TG), epidermal growth factor receptor (EGFR), and E-cadherin and the activity of superoxide dismutase (SOD) in PC-14 and PC-14/ADM cells. There was no change in the cellular levels of P-gp, Topo I, Topo II, and the two isoforms of GSTs. However, SOD activity in PC-14/ADM cells was 2.38 fold higher than that in PC-14 cells. A marked induction of the t-TG expression was also observed in PC-14/ADM cells. In addition to those changes, expressions of EGFR and E-cadherin were down regulated in PC-14/ADM cells. Therefore, molecular modifications such as an increase in SOD activity, induction of the t-TG expression, and down regulation of EGFR and E-cadherin expressions may play important roles in PC-14/ADM cells during the development of ADM resistance.

• 한국미생물·생명공학회지
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• 제33권4호
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• pp.322-326
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• 2005

IgE-dependent histamine-releasing factor (HRF) is found extracellularly to regulate the degranulation process of histamine in mast cells and basophils and known to play a predominant role in the pathogenesis of chronic allergic disease. HRF has been also identified in the intracellular region of the cell. Previously, we reported that HRF interacts with the 3rd cytoplasmic domain of the alpha subunit of Na,K-ATPase and inhibits Na,K-ATPase activity. Since it is known that estroaen activates the sarcolemmal Na,K-ATPase, we tested whether estrogen recovers the Na,K-ATPase activity repressed by HRF. In this study, we showed that estrogen activates Na,K-ATPase repressed by HRF. RT-PCR and western blot analysis showed that estrogen doesn't reduce the expression level of HRF in HeLa cell, suggesting that this recovery effects of estrogen probably occur via indirect mechanism on HRF and Na,K-ATPase.

• 한방안이비인후피부과학회지
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• 제22권2호
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• pp.104-117
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• 2009

Objective : Melanin is one of the most important facor in skin color. Melanin protects human skin from ultraviolet radiation otherwise it causes melanin pigmentation. So this experiment is carried out for test whether Scutellaria baicalensis Georgi(SBG) inhibits melanin synthesis and tyrosinase activity in mouse B16 melanoma cells. Method : The melanin synthesis inhibition effects of SBG were examined by in vitro melanin production assay. We assessed inhibitory effects of SBG on melanin contents from B16F1 melanoma cell, on tyrosinase activity(cell and cell free system), effect of SBG on the expression tyrosinase, Microphthalmia-associated Transcription Factor(MITF), Extracellular signal-regulated Kinase(ERK). Result : SBG inhibited melanin synthesis induced $\alpha$-MSH($\alpha$-Melanin Stimulating Hormone) in B16F1. SBG inhibited tyrosinase activity and expression. And SBG down-regulates MITF and stimulated ERK activation in B16F1. Conclusion : According to above results, SBG was improved its suppression effect to the inhibition of melanin synthesis, tyrosinase activation, and tyrosinase promotor activation. So SBG is considered to be used for an strong source of skin whitening effect.

• Journal of Oral Medicine and Pain
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• 제33권2호
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• pp.105-110
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• 2008

Baicalin은 Scutellaria baicalensis에서 분리되는 flavonoid의 일종으로, 다양한 생물학적 활성을 나타내는 물질로 알려져 있다. Baicalin은 항균, 항염증, 진통작용을 나타내며, nuclear factor-kappaB의 활성을 억제한다고 보고되었다. 최근에 다양한 flavonoid 들이 골조직 대사에 관여함이 밝혀졌으며, 본 연구에서는 baicalin이 골조직의 주요세포인 조골세포의 생성 및 활성에 미치는 영향을 관찰하기 위하여, 세포증식율, 세포생존율, 염기성 인산분해효소 활성 및 osteoprotegerin 생성량의 변화를 관찰하였다. 그 결과 baicalin은 조골세포의 세포 증식과 생존율에는 영향을 미치지 못하였으나, 염기성 인산분해효소의 활성과 osteoprotegerin의 생성량을 증가시켰다. 따라서 baicalin은 골조직에서 조절물질로 역할을 할 것으로 예견된다.

• 대한가정학회지
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• 제45권6호
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• pp.89-100
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• 2007

The objective of this study was to analyze children's maladjustment behavior as related to sex, temperament, and the mother's maternal attitudes, and to characterize the relative influence of these variables on the maladjustment behavior of 3-5 year old children in early child education centers. The subjects were recruited from Gwangju City, and included 217 mothers, and the teachers of their children. Statistical analyses were conducted using SPSSWIN(12.0) for Cronbach's alpha, t-test, one-way ANOVA, Pearson's correlation, and multiple regression analysis. The major findings are as follows; 1. Statistically significant differences existed in the maternal overprotective attitude group with regard to anxiety and withdrawal behaviors. 2. Boys evidenced more aggression, inattention, impulse, and anxiety behaviors than did girls. 3. The activity and adaptation factors of temperaments were significantly different. Increasing activity was associated with increasing aggressive behavior. Increasing adaptation was associated with higher levels of distraction. 4. In terms of maladjustment behaviors in the aggregate, the sex of the children appeared to be the most salient influencing factor, and the activity factor of children's temperament also exerted a significant influence, explaining 13% of maladjustment behavior.

• Archives of Pharmacal Research
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• 제28권5호
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• pp.573-581
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• 2005

Flavonoids, a group of low molecular weight phenylbenzopyrones, have various pharmacological properties including antioxidant activity, anticancer, and immunomodulatory effects. In the present study, lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate/phytohemagglutinin (PMA/PHA) were used as stimulants for RAW 264.7 macrophages and human peripheral blood mononuclear cell (hPBMC), and tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-2 productions were measured. In addition, flavonoids were examined for their effects on LPS-induced NO production in RAW 264.7 macrophages. The results showed that all compounds were not strongly cytotoxic at the tested concentrations on hPBMC and RAW 264.7 macrophages. On immunomodulatory properties, catechin, epigallocatechin (EGC), naringenin, and fisetin repressed NO production and TNF-${\alpha}$ secretion. Furthermore, catechin, epigallocatechin gallate (EGCG), epicatechin (EC), luteolin, chrysin, quercetin, and galangin increased IL-2 secretion while EGC, apigenin, and fisetin inhibited the secretion. These results indicated that flavonoids have the capacity to modulate the immune response and have a potential anti-inflammatory activity. There was no obvious structure-activity relationship regard to the chemical composition of the flavonoids and their cell biological effects.