• The Journal of Advanced Prosthodontics
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• 제6권3호
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• pp.207-214
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• 2014

PURPOSE. This study characterized the synthesis of a modified PMMA (Polymethyl methacrylate) denture acrylic loading platinum nanoparticles (PtN) and assessed its bacterial inhibitory efficacy to produce novel antimicrobial denture base material. MATERIALS AND METHODS. Polymerized PMMA denture acrylic disc ($20mm{\times}2mm$) specimens containing 0 (control), 10, 50, 100 and 200 mg/L of PtN were fabricated respectively. The obtained platinum-PMMA nanocomposite (PtNC) was characterized by TEM (transmission electron microscopy), SEM/EDX (scanning electron microscope/energy dispersive X-ray spectroscopy), thermogravimetric and atomic absorption spectrophotometer analysis. In antimicrobial assay, specimens were placed on the cell culture plate, and $100{\mu}L$ of microbial suspensions of S. mutans (Streptococcus mutans) and S. sobrinus (Streptococcus sobrinus) were inoculated then incubated at $37^{\circ}C$ for 24 hours. The bacterial attachment was tested by FACS (fluorescence-activated cell sorting) analysis after staining with fluorescent probe. RESULTS. PtN were successfully loaded and uniformly immobilized into PMMA denture acrylic with a proper thermal stability and similar surface morphology as compared to control. PtNC expressed significant bacterial anti-adherent effect rather than bactericidal effect above 50 mg/L PtN loaded when compared to pristine PMMA (P=.01) with no or extremely small amounts of Pt ion eluted. CONCLUSION. This is the first report on the synthesis and its antibacterial activity of Pt-PMMA nanocomposite. PMMA denture acrylic loading PtN could be a possible intrinsic antimicrobial denture material with proper mechanical characteristics, meeting those specified for denture bases. For clinical application, future studies including biocompatibility, color stability and warranting the long-term effect were still required.

• Tuberculosis and Respiratory Diseases
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• 제43권2호
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• pp.210-220
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• 1996

식세포인 호중구나 단핵세포는 생체외실험에 사용하기 위한 세포분리법인 플라스틱 표면부착만으로도 세포활성화가 일어나 이후의 실험결과에 영향을 주고 이 과정에 부착분자가 연관되어 있는 것으로 알려져 있다. 폐의 주된 면역세포인 폐포대식세포도 대부분 플라스틱 표면부착에 의해 세포를 분리하므로 사람의 폐포대식세포가 표면부착 자체에 의해 활성화되는지 알아보고 세포활성회에 부착분자와 같은 기전이 관여하는지 밝히기 위해 적어도 한 쪽 폐가 정상인 사람에서 기관지폐포세척술을 통해 얻은 폐포대식세포를 대상으로 표면 부착이 미치는 영향을 과산화수소 분비량 측정으로 분석하여 다음과 같은 결과를 얻었다. 1) 폐포대식세포는 플라스틱 표면에 부착되면 부착 자체에 의해 과산화수소 분비능이 증가하고 이런 상태에서는 PMA나 fMLP와 같은 추가적인 화학자극물질에 의해 과산화수소 분비가 증가되지 않았다. 2) 여러가지 표면중 A549세포단층에 부착될 경우에만 이후의 PMA와 fMLP자극 모두에 의해 과산회수소 분비가 증가하였다. 3) PMA는 세포 부착여부에 관계없이 과산화수소 분비를 자극하지만 fMLP는 폐포대식세포가 표면에 부착된 상태에서만 자극효과가 나타났고 이런 부착세포에서의 fMLP에 의한 과산회수소 분비 효과는 단백합성억제제인 cycloheximide, G단백차 단제인 일해독소와 $\beta_2$ integrin 부착분자에 대한 항체인 항CD18 단세포항체 3가지 모두의 의해 차단되었다. 이상의 결과로 사람의 폐포대식세포는 플라스틱 부착자체에 의해 활성화되므로 부착 이후의 자극물질에 대한 효과가 반감되지만 폐포상피세포와 같은 생물학적 표면에 부착될 경우에는 이후의 세포자극에 민감하게 반응한다는 것을 알 수 있었고, PMA는 세포 부착여부에 관계없이 세포를 자극하는 반면 fMLP는 세포 부착상태에서만 자극효과가 나타나며 이런 부착세포에서의 fMLP에 의한 산소유리기 자극효과는 G단백결합 수용체를 통한 새로운 단백합성 과정으로 이루워지면서 $\beta_2$ integrin을 통한 폐포대식세포와 폐포상피세포의 부착에 의존하는 것으로 사료된다.

• Biomolecules & Therapeutics
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• 제11권2호
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• pp.85-90
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• 2003

Microtubule-binding molecules have been developed as anti-cancer agents to overcome the toxicities of current chemotherapeutics and also have potential for use as anti-angiogenic agents. In this work, we examined the effect of novel triazine compounds, Tubulyzines (microTUBUle LYsing triaZINE), derived from the orthogonal synthesis of a triazine library, on endothelial progenitor cell differentiation. When mononuclear cells isolated from human cord blood were cultured on fibronectin-coated plates for 7 days, all the Tubulyzine compounds A, B, and C (TA, TB, and TC) tested decreased the number of adherent cells in a dose-dependent manner in a coo. centration ranges of 2-5 to $80\mu\textrm{M}$. TA ($IC_{50}$=$20\mu\textrm{M}$) showed slightly more potent activity than TB and TC. Adherent cells treated with TA also exhibited a lower level of ability to ac-LDL uptake, with low ratios of positive cells out of total adherent cells, in a dose-dependent manner and weak expression of endothelial lineage markers, KDR, CD31, and vWF at $20\mu\textrm{M}$. Therefore, these results suggest that tubulyzine A (TA) can be effectively used for the inhibition of new vessel growth by inhibiting differentiation of endothelial progenitor cells.

• 한국동물위생학회지
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• 제35권2호
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• pp.105-109
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• 2012

Apoptosis is a host defense mechanism that the cell uses to limit production of infectious pathogens. Although many bacteria, viruses and parasites can induce apoptosis in infected cells, some pathogens usually exhibit the ability to suppress the induction of apoptosis in the infected cells. Sophisticated evasion strategies of obligate intracellular parasites, in particular prevention of host cell apoptosis, are necessary to ensure successful replication. To study the ability of Eimeria tenella in this regard, in vitro experiments were performed applying Madin-Darby bovine kidney (MDBK) cells as host cell. We have demonstrated that productive infection of adherent cell lines by E. tenella resulted in an anti-apototic effect. This phenomenon was confirmed using in situ terminal deoxynucleotidyl transferase-mediated (TdT) deoxyuridine triphosphates (dUTP)-fluorescein nick end labeling (TUNEL) assay to detect apoptosis. Therefore, E. tenella could complete its cycle of productive infection while inducing anti-apoptosis in the infected cells. This finding might have implications for the pathobiology of E. tenella and other Eimeria species.

• Biomolecules & Therapeutics
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• 제12권4호
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• pp.221-227
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• 2004

Nonsteroidal anti-inflammatory drugs (NSAIDs), particularly the highly selective cyclooxygenase (COX)-2 inhibitors have been shown to decrease the growth of tumor, in part, by inhibition of neovascularization. Recently, besides mature endothelial cells, endothelial progenitor cells (EPCs) have been shown to contribute neovascularization in angiogenic tissues. In this study, we addressed a question whether nimesulide, a selective COX-2 inhibitor, could affect differentiation of EPCs into adhesive endothelial cells in vitro. Total mononuclear cells were isolated from cord blood by Ficoll density gradient centrifugation, and then the cells were incubated with nimesulide or vehicle control for 7 days. The number of adherent and spindle-shaped cells decreased by nimesulide treatment in a concentration-dependent fashion at a concentration range of 5 - 200 ${\mu}M$. Moreover, the adherent cells double positive for DiI-ac-LDL uptake and lectin binding significantly decreased upon nimesulide treatment. There was no change of expression of CD31 between treatment and control groups, whereas slight reduction was detected upon treatment in expression of VE-cadherin, ICAM-1, vWF, ${\alpha}v$, and ${\alpha}5$. Nimesulide also reduced cell viability during first 3 days' culture and induced apoptosis in adherent EPCs, resulting in increased annexin-V-positive and propidium iodide-negative cells. Taken together, these results suggest that nimesulide could be applied for the inhibition of new vessel formation, in part, by inhibiting differentiation and survival of EPCs.

• 한국안광학회지
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• 제21권2호
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• pp.109-117
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• 2016

목적: 본 연구에서는 소프트콘택트렌즈의 재질 특성과 착색 여부가 눈물 성분이 침착된 소프트콘택트렌즈의 포도상구균 흡착에 미치는 영향을 알아보았다. 방법: Etafilcon A, hilafilcon B, nelfilcon A 재질의 투명 소프트콘택트렌즈(이하 투명렌즈)와 써클 소프트콘택트렌즈(이하 써클렌즈)를 대상으로 하여 인공눈물에 침착시키기 전과 후의 흡착 균 수를 측정하였다. 또한, 전기영동법을 통해 인공눈물의 침착 경과시간에 따른 눈물단백질의 변성 정도를 측정하였다. 결과: 포도상구균의 흡착은 콘택트렌즈 재질에 따라 통계적으로 유의하게 차이가 있었다. 투명렌즈와 써클렌즈의 균 흡착 양상에 차이가 있어 etafilcon A 재질에서는 써클렌즈의 균 흡착량이 다소 많았지만, hilafilcon B 및 nelfilcon A 재질에서는 써클렌즈에 흡착된 균수가 각각 투명렌즈의 89.3%, 71.3%였다. 눈물단백질이 침착되었을 경우 흡착된 균의 수가 감소하였으며 감소 정도는 재질에 따라 차이가 있어 etafilcon A 재질 투명소프트콘택트렌즈에서 가장 감소 정도가 컸다. 이러한 눈물단백질의 항균효과는 눈물단백질이 소프트콘택트렌즈에 침착된 시간이 경과될수록 감소하였으며 침착된 라이소자임의 양 역시 감소하였다. 또한, 항균효과의 감소 및 라이소자임 양의 감소가 콘택트렌즈 재질 특성 및 착색여부에 따라 달라졌다. 결론: 본 연구를 통하여 소프트콘택트렌즈의 재질 및 착색여부에 의해 포도상구균의 흡착량이 달라지며, 착색여부보다 렌즈의 재질 특성이 균의 흡착에 많은 영향을 주는 것을 밝혔다. 또한 소프트콘택트렌즈에 침착된 항균단백질의 변성 정도가 렌즈 재질 및 착색여부에 따라 달라지며 이러한 결과가 균의 흡착량에 영향을 미친다는 것을 확인하였다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2008년도 Proceedings of the Convention
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• pp.103-115
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• 2008

Hemodynamic shear stress, the dragging force generated by blood flow, is known as an anti-atherogenic factor. We tested whether lysyl-tRNA synthetase (KRS) will be utilized as an agent controlling shear-sensing systems. KRS was previously known to be secreted as a pro-inflammatory agent. Here we found that KRS inhibited various shear-stimulated signaling pathways. We further found that KRS binds to detergent-resistant membrane (DRM), indicating that KRS binding molecules exist in DRM, specialized regions of the plasma membrane. DRM plays important roles in a variety of cellular processes and consists of gangliosides, signaling molecules and cytoskeletons. We then determined that KRS was colocalized with integrins ${\alpha}4$, ${\alpha}5$ and $av{\beta}3$. In addition, KRS was shown to be associated with sialic acid, existing at the end of gangliosides. Interestingly, the adherent effect of KRS was inhibited by pretreatment with sialic acid. Moreover, treatment of endothelial cells with neuraminidase appeared to inhibit both the KRS adhesion to endothelial cells and shear-stimulated signaling. In conclusion, KRS is likely to be utilized as a vascular regulator.

• Parasites, Hosts and Diseases
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• 제29권2호
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• pp.129-138
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• 1991

자유생활 담수 섬모충류의 일종인 Tetrahymenn Pyriformis는 비특이적으로 복강 대식세포를 활성화하여 미생물 살멸효과가 있음이 밝혀졌으나 한국에서 순수분리 배양된 GL주(주)에 대한 평가는 시행된 바 없어 본 섬모충의 추출액을 ICR 마우스 복강 내로 주사하여 복강 대식세포를 활성화한 다음 실험실 내에서 표적 기생 원충인 Toxoplasma gondii (RH 주)를 접촉시켜 시간별로 Togoplasma 살멸 효과를 보아 대식세포의 환성도를 평가하였던 바 다음과 같은 결론을 얻었다. 표적 기생 원충으로서 살아있는 Toxoplasma 영양형을 주입하였을 경우, 대식세포 활성제 처리 실험군은 물론 대조군에서도 모두 처리 1분 이내에 Toxoplasma가 숙주세포내로 침입 내지 탐식되었으며 이때 탐식지수 범위는 15∼51%였다. 대조군에서는 배양 시간에 따라 100개의 대식세포당 총 탐식 표적 기생충 수가 증가하였으나 활성제 처리군에서는 배양 20시간에 그 수가 모두 줄었고 Tetrahymena 처리군에서는 총 표적 기생충 수가 14, 탐식지수 10%로서 가장 왕성한 대식세포 활성도를 나타내었다. 화학 함성 활성제로서는 dimethyldioctadecylammonium bromide (DDA)가 Tetrakymena와 대차 없는 대식세포 활성효과를 보였다. 표적 기생 편충으로서 열처리 Tonxplasma 영양형을 주입하였을 경우, 대조군을 포함한 모든 실험군에서 처리 1분 이내에 역시 Toxoplasma 가 숙주 세포에 의해 탐식되었으며 탐식지수 범위는 8∼25%여서 살아있는 영양형을 처리하였을 때보다 낮은 범위를 보였다. 이때 Tetrakymena 처리군에서는 탐식지수 4%, 대식세포 100개당 표적 세포 총수가 4로서 Texoplasma 추출액 처리군과 함께 가장 우수한 활성제로 평가되었으며 화학합성 활성제로서는 DDA, dextran sulfate, complete Freund's adjutant 순으로 환성 효과가 높았다 이상의 결과로 보아 T. pyriformis (GL 주)는 화학합성 활성제보다 우수한 Toxoplasma 살멸 효과를 나타내었고, 실험실 내에서 대량 무균 배양될 수 있어 앞으로 대식세포 활성제로서, 나아가 Toxopzasma 감염 억제제로서 널리 이용될 가능성이 있을 것으로 생각되었다.

• Journal of Periodontal and Implant Science
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• 제32권3호
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• pp.665-683
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• 2002

A novel glucanhydrolase from a mutant of Lipomyces starkeyi KSM 22 has additional amylase activity besides mutanolytic activity and has been suggested as promising anti-plaque agent. It has been shown effective in hydrolysis of mutan, reduction of mutan formation by Streptococcus mutans and removal pre-formed sucrose-dependent adherent microbial film and has been strongly bound to hydroxyapatitie. These in vitro properties of Lipomyces starkeyi KSM 22 glucanhydrolase are desirable for its application as a dental plaque control agent. In human experimental gingivitis　model and 6 month clinical trial, mouthrinsing with Lipomyces　starkeyi KSM 22 dextranase was comparable to 0.12% chlorhexidine mouthwash in inhibition of plaque accumulation and gingival inflammation and local side effect was negligible. This study was aimed to evaluate the cytotoxic effect of Lipomyces starkeyi KSM 22 glucanhydrolase on human gingival fibroblasts. Primary culture of human gingival fibroblasts at the 4th to 6th passages were used. Glucanhydrolase solution was made from lyophilized glucanhydrolase powder from a mutant of Lipomyces stakeyi KSM 22 solved in PBS and added to DMEM medium to the final concentration of 0.5, 1, and 2 unit. Cells were exposed to glucanhydrolase solution or 0.1 % chlorhexidine and the cells cultured in DMEM with 10% FBS and 1% antibiotics as control. After exposure, the morphological change, cell attachment, and cell activity by MTT assay were evaluated in 0.5, 1.5, 3, 6, 24 hours after treatment. The cell proliferation and cell activity was also evaluated at 2 and 7 days after 1 minute exposure, twice a day. The cell morphology was similar between the Lipomyces smkeyi KSM 22 glucanhydrolase groups and control group during the incubation periods, while most fibroblasts remained as round cell regardless of incubation time in the chlorhexidine group. The numbers of the attached cells in the glucanhydrolase groups were comparable to that of control and significantly higher than the chlorhexidine group. The numbers of the proliferated cells in the glucanhydrolase groups at 7 days of incubation were comparable to the control group and higher than the chlorhexidine group. The cell activity in glucanhydrolase groups paralleled with the increased cell number by attachment and proliferation. According to these results, Lipomyces starkeyj KSM 22 glucanhydrolase has little harmful effect on attachment and proliferation of human gingival fibroblasts, in contrast to 0.1% chlorhexidine which was cytotoxic to human gingival fibroblasts. Therefore this glucanhydrolase preparation is considered as a safe and promising agent for new mouthwash formula in the near future.