• 구강회복응용과학지
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• 제17권3호
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• pp.199-204
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• 2001

This study was to investigate the reused possibility of zirconia reinforced glass-ceramic(IPS Empress Cosmo ceramic) with sprue button in the flexure strength and fracture toughness. 40 disk-shaped ceramic specimens (20 specimens: as-pressed material; 20 specimens: reused material) with approximately 1.7 mm thickness and 15 mm diameter were prepared by "lost wax" technique. The remnants(sprue buttons) were used for repressing. The surface treatments for the discs were gradually abraded with 320, 800, 1200, and 2000 grit SiC sandpaper. The specimens were evaluated their flexure strength with the biaxial flexure jig(ball-on-three balls) and their fracture toughness with Vickers Indentation-microfracture test. The Weibull moduli were calculated for biaxial flexural strength. The mean flexure strength and fracture toughness of each group were $122.2{\pm}18.3MPa$, $1.00{\pm}0.09MPa{\cdot}m^{0.5}$ (as-pressed ceramics), and $122.2{\pm}20.3MPa$, $1.01{\pm}0.10MPa{\cdot}m^{0.5}$ (reused ceramics). There were no significant differences in the strength and the fracture toughness between the as-pressed and the reused IPS Empress Cosmo ceramic (P>0.05). This implied zirconia reinforced glass-ceramic(IPS Empress Cosmo ceramic) could be used one more time by reusing of sprue button in the flexure strength and fracture toughness.

• 동의생리병리학회지
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• 제24권5호
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• pp.831-836
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• 2010

In addition to spice, black pepper (Piper nigrum Linne : PnL) has been used as herbal medicine because of its function in anti-oxidation, anti-inflammation, and anti-carcinogenesis. Recently, it has been reported that piperine, a component of PnL, inhibits adipocyte differentiation by repressing various adipogenic gene expressions. In this study, we determined whether piperine is a major constituent of PnL that confers the anti-adipogenic activity at whole genome level. Differentiation of 3T3-L1 pre-adipocytes was induced in presence of PnL extract or piperine. To compare genes that are regulated by PnL extract or piperine, we performed expression profiling using microarrays (Agilent Mouse 44k 4plex). RNA samples were labeled with Cy3 and Cy5, respectively. Labeled samples were hybridized to the microarrays. Results were filtered and cut off set p<0.05. Genes exhibiting significant differences in expression level were classified into Gene Ontology (GO)-based functional categories (http://www.geneontology.org) and KEGG (http://www.genome.jp/kegg/). Extract of PnL and its component piperine reduced lipid accumulation in 3T3-L1 cells during adipogenesis. Such anti-adipogenic activity appears to result from down-regulation of transcription factor genes involved in adipogenesis, and other genes involved in fatty acid synthesis, transport, triglyceride synthesis, and carbohydrate metabolism. These genome-wide studies lead to conclude that piperine, as a critical component of PnL, plays common role with PnL in anti-adipogenesis.

• Asian Pacific Journal of Cancer Prevention
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• 제16권6호
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• pp.2397-2402
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• 2015

Previous studies have shown that miR-454 plays an important role in a variety of biological processes in various human cancer cells. However, the underlying mechanisms of this microRNA in colorectal cancer (CRC) cells remain largely unknown. In the present study, we investigated the miR-454 role in CRC cell proliferation. We found that miR-454 expression is markedly upregulated in CRC tissues and CRC cells compared with the matched tumor adjacent tissues and the FHC normal colonic cell line. Ectopic expression of miR-454 promoted the proliferation and anchorage-independent growth of CRC cells, whereas inhibition of miR-454 reduced this effect. Bioinformatics analysis further revealed cylindromatosis (CYLD), a putative tumor suppressor as a potential target of miR-454. Data from luciferase reporter assays showed that miR-454 directly binds to the 3'-untranslated region (3'-UTR) of CYLD mRNA and repressed expression at both transcriptional and translational levels. In functional assays, CYLD-silenced in miR-454-in-transfected SW480 cells have positive effect to promote cell proliferation, suggesting that direct CYLD downregulation is required for miR-454-induced CRC cell proliferation. In sum, our data provide compelling evidence that miR-454 functions as an onco-miRNA, playing a crucial role in the promoting cell proliferation in CRC, and its oncogenic effect is mediated chiefly through direct suppression of CYLD expression.

• 한국지역지리학회지
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• 제20권4호
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• pp.425-443
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• 2014

본 논문은 두 가지 주제를 고찰하였다. 우선, 본 논문은 죽음이라는 현상을 실제적으로 이해하기 위해 국외 인문 지리학 영역에서 축적되어 온 연구 성과를 고찰하였다. 이 결과 1950년대부터 물질 경관의 외형 변화에 주목하는 죽음의 지리가 1990년대 무렵 경관 이면의 배경과 맥락에 주목하는 죽음경관 연구로 변동했음을 알 수 있었다. 둘째, 본 논문은 이 연구를 기반으로 하여 근대 이후 한국의 경우 어떠한 제도적 담론이 시민사회의 죽음경관의 배제와 포섭에 개입하였는지를 분석하고자 했다. 그 결과 국가가 기존 죽음경관인 묘지를 억제하기 위해 '여의도', '불법 호화 무연고묘지' 담론 같은 배제 의식을 생산해 왔음을 알 수 있었다. 또한, 화장, 납골, 산골(散骨) 시설 등의 도입을 촉진하기 위해 '통일신라', '선진국', '님비'를 핵심으로 하는 여러 담론을 생산해 왔음을 알 수 있었다. 결과적으로 이러한 담론의 발현 과정에서 특정한 사실들이 진실로 수용되고 그 이면의 모순들이 은폐되는 현상들을 포착하였다.

• Journal of Ginseng Research
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• 제33권1호
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• pp.1-7
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• 2009

우리 몸의 많은 기관을 비롯하여 장기들은 반복적이거나 혹은 급성 스트레스를 이겨내지 못하고 만성 스트레스로 이어질 경우 질병이 생기게 된다. 특히 강하고 지속적인 스트레스에 노출되면 뇌의 해마 수지상 세포(hippocampal dendrites)가 위축되거나 크기가 작아진다. 이렇게 스트레스로 인하여 증가된 글루코 코티코이드 호르몬은 뉴런 흥분제인 glutamate를 유도하거나 에너지 대사를 변형시켜 신경 독작용을 일으킨다. 이러한 연속적인 반응은 TNF-$\alpha$ convertase(TACE)를 활성화시켜 TNF-$\alpha$가 분비되도록 하여 전사 조절자인 NF-${\kappa}B$가 핵내로 전이되고 신경 손상을 일으키는 iNOS와 COX-2와 같은 효소를 유도한다. 이런 산화적 스트레스의 상위조절인자 TACE는 스트레스에 의한 여러 가지 염증성 질환 및 숙주방어에서 가장 중요한 조절자인 TNF-alpha를 수용체로부터 "유리(shedding)" 시키는 역할을 한다. 따라서 이런 신호 전달계를 자극하는 TACE의 발현 양과 이로 인한 지속적인 처리과정이 중요한 문제로 대두되고 있다. 특히 여러 스트레스 중에서 고정화 스트레스 및 신체적 구속 스트레스에 대한 연구는 뇌에서 산화물 생성을 증가시키지만 인삼이 뇌의 산화물질 생성에 어떤 영향을 미치는지 체계적인 연구가 진행된 바 없다. 따라서 염증을 매개하는 TNF-alpha의 생산에 중요한 역할을 하는 TACE의 발현 조절 및 TNF-alpha 신호전달을 연구함으로써 인삼의 항산화 기전을 분자 수준에서 규명할 수 있게 될 것으로 기대된다.

• 대한한방내과학회지
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• 제37권3호
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• pp.442-452
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• 2016

Objectives: This study was performed to investigate the anti-lipogenic effect and the mechanism of Jungmanbunso-hwan extract (JMBSH) on a cellular model of non-alcoholic fatty liver disease (NAFLD) caused by palmitate in HepG2 cells.Methods: The JMBSH was prepared, andHepG2 cells were treated with various concentrations of JMBSH in order to perform an MTT assay. The HepG2 cells were cultivated in palmitate-containing media with or without extract of JMBSH. The intracellular lipid content in the HepG2 cells was examined. The effects of JMBSH on sterol regulatory element-binding transcription factor-1c (SREBP-1c), acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), stearoyl-CoA desaturase-1 (SCD-1), and AMP-activated protein kinase (AMPK) activation in HepG2 cells were measured.Results: JMBSH did not reduce HepG2 cell viability under 1,000 μg/mL. JMBSH considerably decreased intracellular lipid accumulation caused by palmitate in HepG2 cells. JMBSH repressed expression of SREBP-1c, which mediates the induction of lipogenic genes (ACC, FAS, and SCD-1). JMBSH also activated AMPK, which plays animportant role in the regulation of hepatic lipid metabolism.Conclusions: This study suggested that JMBSH relieves hepatic steatosis by repressing SREBP-1c, which mediates the induction of lipogenic genes. The anti-lipogenic effect of JMBSH may also be related to the activation of AMPK. Therefore, JMBSH could potentially be applied to NAFLD treatment after further clinical studies.

• Journal of Ginseng Research
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• 제34권2호
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• pp.138-144
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• 2010

Ginseng (Panax ginseng C.A. Meyer) has been shown to have anti-stress effects in animal studies. However, most studies have only managed to detect altered levels of biomarkers or enzymes in blood or tissue, and the actual molecular mechanisms by which ginseng exerts these effects remain unknown. In this study, the anti-oxidative effect of Korean red ginseng (KRG) was examined in human SK-N-SH neuroblastoma cells. Incubation of SK-N-SH cells with the oxidative stressor hydrogen peroxide resulted in significant induction of cell death. In contrast, pre-treatment of cells with KRG decreased cell death significantly. To elucidate underlying mechanisms by which KRG inhibited cell death, the expression of apoptosis-related proteins was examined by Western blot analysis. KRG pre-treatment decreased the expression of the pro-apoptotic gene caspase-3, whereas it increased expression of the anti-apoptotic gene Bcl-2. Consistent with this, immunoblot analysis showed that pre-treatment of the SK-N-SH cells with KRG inhibited expression of the pro-inflammatory gene cyclooxygenase 2 (COX-2). RT-PCR analysis revealed that the repression of COX-2 expression by KRG pre-treatment occurred at the mRNA level. Taken together, our data indicate that KRG can protect against oxidative stress-induced neuronal cell death by repressing genes that mediate apoptosis and inflammation.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.811-819
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• 1999

The ${\beta}-CGTase$ gene of alkalophilic Bacillus firmus var. alkalophilus was cloned into E. coli using $pZErO^{TM}-2$ as a vector. The cloned gene encoded a total of 710 amino acid residues consisting of 674 amino acids of the matured protein and 36 amino acids of the signal peptide, including 20 amino acids from the lacZ gene in the vector. Although the cloned ${\beta}-CGTase$ gene did not contain the promoter and start codons, it was expressed by the lac promoter and lacZ start codon in the $pZErO^{TM}$ vector. A comparison was made with the amino acid sequence and ten other CGTases from Bacillus sp. Also, ten highly conserved regions, which are important amino acid residues in catalysis of CGTase, were identified. The lac promoter used for expression of the ${\beta}-CGTase$ gene was induced constitutively in recombinant E. coli even without IPTG possibly because of a lack of the lacI gene in both host and vector, repressing the lacZ gene in the lac operon. Its expression was catabolically repressed by glucose, however, its repression was reduced by soluble starch, mainly because of the extremely high increase of the cAMP level. ${\beta}-CGTase$ can be overproduced in the recombinant E. coli by maintaining intracellular cAMP levels mostly through the intermittent feeding of glucose during cultivation.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.835-840
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• 2013

Accumulating evidence has shown that microRNAs are involved in cancer development and progression. However, it remains unknown about the potential role of miR-19a in the pathogenesis of gastric cancer. Here, we report that suppressor of cytokine signaling 1 (SOCS1) is a novel target of miR-19a in gastric cancer cells and that miR-19a expression is inversely correlated with SOCS1 expression in gastric cancer cells and a subset of gastric cancer tissues. Ectopic expression of miR-19a dramatically promoted proliferation and tumorigenicity of gastric cancer cells both in vitro and in vivo. Moreover, we showed that silencing of SOCS1 promoted cell growth and colony formation resembling that of miR-19a overexpression, whereas re-introduction of SOCS1 (without the 3'-UTR) attenuated the pro-tumorigenic functions. Taken together, our findings suggest that the SOCS1 gene is a direct target of miR-19a, which functions as an oncogenic miRNA in gastric cancer by repressing the expression of tumor suppressor SOCS1.

• 동의생리병리학회지
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• 제25권3호
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• pp.459-465
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• 2011

The nuclear factor of activated T cells (NFAT) protein induces transcriptions of cytokine genes including IL-2 for T-cell activation. Normally activation of NFAT is important to induce immune responses but excessive NFAT activation provokes immunopathological reactions such as autoimmunity, transplant rejection, and inflammation. Thus, for the treatment of autoimmune diseases drugs repressing the activation of NFAT have been searched. In this study, immnunosuppressive effects of Rosa chinensis Jacq. extracts identified as a potent NFAT inhibitor from a natural product library were examined. NFAT reporter assay, MTS assay, real time PCR, IL-2 ELISA, MLR, and FACS (Fluorescent Activated Cell Sorting) were used to measure inhibitory immunocyte activities of Rosa chinensis Jacq. The variety of natural products have been screened and some were found to show inhibitory activities against the NFAT transcription factor. Among them, extract of Rosa chinensis Jacq. showed an strong inhibitory effect on the activation of NFAT without affecting cell viability. Levels of IL-2 transcripts as well as IL-2 protein were decreased with treatment of Rosa chinensis Jacq. extract. In addition, immunosuppressive activity of Rosa chinensis Jacq. extract was exhibited in the mixed leukocytes reaction. The increasement of CD4+CD25+ (Treg) immunocyte was also detected in the analysis using FACS after applying Rosa chinensis Jacq. extract. Immunosuppressive effects of the Rosa chinensis Jacq. extracts were clearly demonstrated in the present study. In addition, Rosa chinensis Jacq. extract also positively affected regulatory T cell induction. Further investigations in particular on purification of single substance responsible for the immunosuppressive effects from the extract and analysis on possible actions of the extract in interfering cell signaling and cytokine production will be needed.