• 대한약침학회지
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• 제19권4호
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• pp.312-318
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• 2016

Objectives: Bacterial resistant infections have become a global health challenge and threaten the society's health. Thus, an urgent need exists to find ways to combat resistant pathogens. One promising approach to overcoming bacterial resistance is the use of herbal products. Green tea catechins, the major green tea polyphenols, show antimicrobial activity against resistant pathogens. The present study aimed to investigate the effect of catechins, green tea extract, and methylxanthines in combination with gentamicin against standard and clinical isolates of Staphylococcus aureus (S. aureus) and the standard strain of Pseudomonas aeruginosa (P. aeruginosa). Methods: The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values of different agents against bacterial strains were determined. The interactions of green tea extract, epigallate catechin, epigallocatechin gallate, two types of methylxanthine, caffeine, and theophylline with gentamicin were studied in vitro by using a checkerboard method and calculating the fraction inhibitory concentration index (FICI). Results: The MICs of gentamicin against bacterial strains were in the range of $0.312-320{\mu}g/mL$. The MIC values of both types of catechins were $62.5-250{\mu}g/mL$. Green tea extract showed insufficient antibacterial activity when used alone. Methylxanthines had no intrinsic inhibitory activity against any of the bacterial strains tested. When green tea extract and catechins were combined with gentamicin, the MIC values of gentamicin against the standard strains and a clinical isolate were reduced, and synergistic activities were observed (FICI < 1). A combination of caffeine with gentamicin did not alter the MIC values of gentamicin. Conclusion: The results of the present study revealed that green tea extract and catechins potentiated the antimicrobial action of gentamicin against some clinical isolates of S. aureus and standard P. aeruginosa strains. Therefore, combinations of gentamicin with these natural compounds might be a promising approach to combat microbial resistance.

• Journal of Periodontal and Implant Science
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• 제34권1호
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• pp.195-204
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• 2004

A novel glucanhydrolase from Lipomyces starkeyi KSM 22 has been suggested as a promising anti-plaque agent because it has been shown to have additional amylase activity and mutanase activity besides dextranase activity and to strongly bind to hydroxyapatite. Mouthrinsing with Lipomyces starkeyi KSM 22 glucanhydrolase solution was comparable to 0.12% chlorhexidine mouthwash in inhibition of plaque accumulation and gingival inflammation and local side effects were less frequent and less intense in human experimental gingivitis. In this study, Lipomyces starkeyi KSM 22 glucanhydrolase mouthrinses (1 and 2 unit/ml) were compared with a control mouthrinse (commercial 0.01% benzethonium chloride mouthrinse, $Caregargle^{(R)}$, Hanmi Pharmaceuticals) in the ability to inhibit plaque formation. A 3-replicate clinical trial using 4-day plaque regrowth model was used. Fifteen volunteers were rendered plaque-free on the 1st day of each study period, ceased toothcleansing, and rinsed 2X daily with allocated mouthrinse thereafter. On day 5, plaque accumulation was scored and the washout periods was 9 days for the next trial. Lipomyces starkeyi KSM22 glucanhydrolase(1 unit and 2 unit)- containing mouthrinse resulted in Significantly lower plaque formation in plaque area and thickness, compared to the control mouthrinse. There was no significant difference in plaque inhibition between enzyme-mouthrinses at 2 different concentrations used. This glucanhydrolase- containing mouthwash resulted in significantly lower plaque area severity index score and tended to have lower plaque thickness severity index score than those of control mouthrinse. But there was no significant difference according to the enzyme concentration. From these results, Lipomyces starkeyi KSM 22 glucanhydrolase-containing benzethonium chloride mouthrinse has greater anti-plaque effect than the commercial mouthrinse alone. Therefore this glucanhydrolase preparation is a promising agent for new mouthwash formulation in the near future.

• 한국항만경제학회지
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• 제31권3호
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• pp.141-153
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• 2015

부산항의 수출이 우리나라 항만의 수출에서 차지하는 비중은 계속해서 감소하고 있는데, 이와 같은 항만의 위상변화는 해당 항만의 주요 수출시장과 수출품목에서 그 원인을 찾아볼 수 있다. 본고는 중국에 대한 부산항의 주요 10개 수출품목의 경쟁력이 어떻게 변화할 것인가를 밝히기 위해 시장비교우위(Market Comparative Advantage: MCA)지수를 도출하여 변화하는 행태를 분석함과 동시에 MCA지수를 대 중국 수출비중과 중국의 수입비중으로 분해한다. 부산항의 수출경쟁력은 MCA지수가 하락한 HS8703 품목을 제외한 9개 품목에서 상승하나, 이 중 7개 품목에서 중국의 수입비중이 감소함을 보인다. 그런데 중국의 수입비중이 줄어든다는 것은 시장비교우위지수가 상승하여도 수출증가를 낙관할 수 없다는 것을 의미한다. 중국의 수입비중이 감소하는 7개 품목에서 5개 품목은 대중 수출비중이 상승하나 2개 품목에서는 대중 수출비중도 함께 하락하여 MCA의 상승에도 불구하고 수출전망이 어둡다는 것을 보인다. 결국 HS3920, HS8708, HS8703과 같은 3개 품목에서만 수출경쟁력 향상이 수출전망을 밝게 한다는 것을 밝힌다. HS8708 품목이 부산항의 대중 수출에서 1위를 차지하는 품목이라는 점은 부산항의 대중 수출에 긍정적인 요소가 될 수 있으나, 10개 품목 중 3개 품목에서만 수출전망이 밝다는 것은 부산항의 대중 수출에 대해 전반적인 검토가 있어야 한다는 것을 보인다.

• Annals of Occupational and Environmental Medicine
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• 제35권
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• pp.24.1-24.15
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• 2023

Background: The construction workers are vulnerable to fatigue due to high physical workload. This study aimed to investigate the relationship between overwork and heart rate in construction workers and propose a scheme to prevent overwork in advance. Methods: We measured the heart rates of construction workers at a construction site of a residential and commercial complex in Seoul from August to October 2021 and develop an index that monitors overwork in real-time. A total of 66 Korean workers participated in the study, wearing real-time heart rate monitoring equipment. The relative heart rate (RHR) was calculated using the minimum and maximum heart rates, and the maximum acceptable working time (MAWT) was estimated using RHR to calculate the workload. The overwork index (OI) was defined as the cumulative workload evaluated with the MAWT. An appropriate scenario line (PSL) was set as an index that can be compared to the OI to evaluate the degree of overwork in real-time. The excess overwork index (EOI) was evaluated in real-time during work performance using the difference between the OI and the PSL. The EOI value was used to perform receiver operating characteristic (ROC) curve analysis to find the optimal cut-off value for classification of overwork state. Results: Of the 60 participants analyzed, 28 (46.7%) were classified as the overwork group based on their RHR. ROC curve analysis showed that the EOI was a good predictor of overwork, with an area under the curve of 0.824. The optimal cut-off values ranged from 21.8% to 24.0% depending on the method used to determine the cut-off point. Conclusion: The EOI showed promising results as a predictive tool to assess overwork in real-time using heart rate monitoring and calculation through MAWT. Further research is needed to assess physical workload accurately and determine cut-off values across industries.

• 한국안전학회지
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• 제35권4호
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• pp.92-100
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• 2020

Along with the rapid development of industrial technology, the industrial structure has been continuously changed. Accordingly, safety technologies have been gradually developed to be applied into various industrial fields as well, not limited to a specific industry area. As a result, it became important to analyze and predict trends of safety technology development in order to establish technology strategies for industrial safety. In particular, since patents are easily accessible to gather the technology and business information, many studies have highlighted technology forecasting using patent information. Thus, this study proposes the patent analysis of monitoring trends of safety technologies of industry fields, taking into account both static and dynamic aspects through index and text analysis. First, patent documents containing safety-related keywords are collected from the WIPSON database for extracting technology information. Then, the development trends of safety technologies by industry fields are identified and analyzed through the analysis of indicators such as marketability, growth, and activation. The results of various indicator analyses of safety technologies are visualized to compare among industrial safety technologies for businesses and technology developers. Second, textmining algorithm is applied to identify trends of specific technology keywords of major industries extracted from patent index analysis. As a result, it is expected that the safety manager uses the patent analysis of safety technologies to provide safety technology information with safety-related companies and institutes. The extracted safety technologies are applicable to business practice and predict future promising technologies.

• Journal of Periodontal and Implant Science
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• 제44권2호
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• pp.71-78
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• 2014

Purpose: Host modulatory therapy has been proposed as a treatment for periodontal diseases. A class of herbal medicines, known to be immunomodulators, alters the activity of immune function through the regulation of informational molecules such as cytokines. In the current study, we tested the hypothesis that herbal immunomodulator drugs act as an adjuvant to scaling and root planing (SRP) in alleviating periodontal inflammation by improving clinical and biochemical parameters. Methods: Sixty healthy subjects (30 in each group) with moderate and severe chronic periodontitis were enrolled in a double-blind, placebo-controlled, double-masked randomised controlled trial. The control group was treated with SRP and a placebo, whereas the test group was treated with SRP followed by dietary supplementation of Septilin for 3 weeks. Periodontal clinical parameters and serum C-reactive protein (CRP) levels were evaluated for all patients at the baseline, 3 weeks, and 6 weeks. Results: Improved gingival index scores found in the test group as compared to the control group were found to be statistically significant only after 3 weeks (P<0.001). In contrast, the decrease in the sulcus bleeding index and pocket depth scores was statistically highly significant in the test group as compared to the control group after 3 weeks and 6 weeks (P<0.001). However, reduced clinical attachment level and CRP scores, as reflected in the test group as compared to the control group, were not found to be statistically significant after both 3 weeks (P>0.05) and 6 weeks (P>0.05). Conclusions: The results of this clinical-biochemical study suggest that dietary supplementation with herbal immunomodulatory agents may be a promising adjunct to SRP and may aid in improving periodontal treatment outcomes.

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6507-6512
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• 2015

Background: Vaspin and Retinol binding protein-4 (RBP4) are new adipokines mainly produced by adipose tissue. Considering that medullary thyroid carcinoma (MTC) is a malignant neuroendocrine tumor, and to date the relationship between serum levels of vaspin and RBP4 with MTC has not been studied, in this matched case-control study we evaluated their possible significance to this tumor type. Materials and Methods: A total of 45 patients with MTC (21 males and 24 females) and 45 healthy persons as a control group (24 males and 21 females) were selected. The two groups were matched for age, sex and body mass index. Serum Vaspin and RBP4 levels were measured by enzyme-linked immunosorbent assay (ELISA) methods in both groups. Also, weight and height were measured and body mass index was calculated too. Results: In total, patients with MTC had significantly higher serum vaspin levels compared to the controls (0.52ng/ml vs. 0.45ng/ml, P=0.0241). However, no significant difference was found in serum RBP4 concentrations between the patients with MTC and the controls ($15.2{\pm}2.55{\mu}g/ml$ versus $15.1{\pm}3.34{\mu}g/ml$, p>0.05). Conclusions: The results of this study demonstrated that serum RBP4 levels in MTC patients are not significantly different from those found in healthy individuals and did not correlate with MTC. On the other hand, higher levels of serum vaspin are associated with an increased risk of MTC. Thus Vaspin may be a novel and promising biomarker for diagnosis or confirmation of MTC in conjunction other specific tumor markers.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.5855-5860
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• 2013

Phytochemicals are among the natural chemopreventive agents with most potential for delaying, blocking or reversing the initiation and promotional events of carcinogenesis. They therefore offer cancer treatment strategies to reduce cancer related death. One such promising chemopreventive agent which has attracted considerable attention is sulforaphane (SFN), which exhibits anti-cancer, anti-diabetic, and anti-microbial properties. The present study was undertaken to assess effect of SFN alone and in combination with a chemotherapeutic agent, gemcitabine, on the proliferative potential of MCF-7 cells by cell viability assay and authenticated the results by nuclear morphological examination. Further we analyzed the modulation of expression of Bcl-2 and COX-2 on treatment of these cells with SFN by RT-PCR. SFN showed cytotoxic effects on MCF-7 cells in a dose- and time-dependent manner via an apoptotic mode of cell death. In addition, a combinational treatment of SFN and gemcitabine on MCF-7 cells resulted in growth inhibition in a synergistic manner with a combination index (CI)<1. Notably, SFN was found to significantly downregulate the expression of Bcl-2, an anti-apoptotic gene, and COX-2, a gene involved in inflammation, in a time-dependent manner. These results indicate that SFN induces apoptosis and anti-inflammatory effects on MCF-7 cells via downregulation of Bcl-2 and COX-2 respectively. The combination of SFN and gemcitabine may potentiate the efficacy of gemcitabine and minimize the toxicity to normal cells. Taken together, SFN may be a potent anti-cancer agent for breast cancer treatment.

• 한국균학회지
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• 제43권2호
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• pp.92-98
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• 2015

대표적인 담수습지인 경상남도 창원시 주남저수지와 동판저수지에서 우점하는 수생식물종인 자라풀 및 생이가래를 채집하였다. 주남저수지의 자생식물 뿌리에서 19균주와 동판저수지의 자생식물 뿌리에서 9균주를 순수분리 하였다. 이들 내생균류들의 internal transcribed spacer (ITS) 영역 염기서열을 분석하여 계통수를 작성한 결과 분리된 28균주는 주남저수지의 경우 11속, 동판저수지의 경우 5속에 속하는 것으로 확인되었으며, 두 습지에서 모두 13속의 내생균류가 분리되었다. 이들 중 담수습지별로 공통적으로 분리된 균주는 Fusarium, Phoma 및Talaromyces속으로 확인되었다. 담수습지 및 식물종별 내생균류의 다양성을 분석하였을 때 각각 상이한 지수를 보였으며, 그들 중 환경생태학적으로 중요한 위치를 차지하는 생이가래가 높은 지수를 나타내었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.76-76
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• 2008

The resonance properties due to the surface plasmon(SP) excitation of metal nanoparticles make the nanocomposite films promising for various applications such as optical switching devices. In spite of the well-known ultra-sensitive operation of optical switches based on a guided wave, the application of nanocomposite film(NC) has inherent limitation originating from the excessive optical loss related with the surface plasmon resonance(SPR). In this study, we addressed this problem and present the experimental and theoretical analysis on the pump-probe optical switching in prism-coupled Au(1 vol.%):$SiO_2$ nanocomposite waveguide film. The guided mode was successfully generated using a near infrared probe beam of 1550 nm and modulated with an external pump beam of 532 nm close to the SPR wavelength. We extend our approach to ultra-fast operation using a pulsed laser with 5 ns pulse width. To improve the switching speed through the reduction in thermal loading effect accompanied by the resonant absorption of pump beam light, we adopted a metallic film as a coupling layer instead of low-index dielectric layer between the high-index SF10 prism and NC slab waveguide. We observed great enhancement in switching speed for the case of using metallic coupling layer, and founded a distinct difference in origin of optical nonlinearities induced during switching operation using cw and ns laser.