• 대한소아치과학회지
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• 제25권4호
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• pp.691-703
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• 1998

Saliva is obviously potential medium to protect the dental caries by not only physical clearing effect, but aggregating action of protein with bacteria. Nevertheless, we still do not understand how the dental caries occur and what brings the individual difference in caries prevalence. In the regards of dental caries prevalence, we hypothesized that the composition of salivary protein might be different from caries susceptible group to caries resistant group. The purposes of this experiment were focused on the molecular analysis of salivary proteins from the subjects who were involved in multiple caries. Electrophoretic analysis was done on the whole saliva collected from the children with and without multiple caries. We found 86.2% of subjects with multiple caries has approximately 120 KDa protein band while 30.4% in the healthy subjects. And the concentration of the total protein on the subjects with multiple caries is significantly higher than that of the healthy group. However, it turned out that the difference of the salivary composition does not affect the bacterial adhesion to hydroxyapatite bead. With regards of enzymes in saliva, the activity of ${\alpha}-amylase$ and lactate dehydrogenase does not have any significant difference between both groups. However, the concentrations of $Na^+\;and\;Cl^-$ in saliva from multiple caries group is higher than that of the control group. Taken all together, it may be concluded that 120 KDa protein in saliva may be associated with the process of dental caries, also the high concentration of protein and $Na^+,\;Cl^-$ in saliva may be linked to dental caries development as a cofactors.

• International Journal of Oral Biology
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• 제41권1호
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• pp.17-23
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• 2016

Chronic/cyclic neutropenia, leukocyte adhesion deficiency syndrome, Papillon-$Lef{\grave{e}}vre$ syndrome, and $Ch{\grave{e}}diak$-Higashi syndrome are associated with severe periodontitis, suggesting the importance of neutrophils in the maintenance of periodontal health. Various Toll-like receptor (TLR) ligands are known to stimulate neutrophil function, including FcR-mediated phagocytosis. In the present study, the effect of TLR2 activation on the non-opsonic phagocytosis of oral bacteria and concomitant production of reactive oxygen species (ROS) by human neutrophils was evaluated. Neutrophils isolated from peripheral blood were incubated with Streptococcus sanguinis or Porphyromonas gingivalis in the presence of various concentrations of $Pam_3CSK_4$, a synthetic TLR2 ligand, and analyzed for phagocytosis and ROS production by flow cytometry and chemiluminescence, respectively. $Pam_3CSK_4$ significantly increased the phagocytosis of both bacterial species in a dose-dependent manner. However, the enhancing effect was greater for S. sanguinis than for P. gingivalis. $Pam_3CSK_4$ alone induced ROS production in neutrophils and also increased concomitant ROS production induced by bacteria. Interestingly, incubation with P. gingivalis and $Pam_3CSK_4$ decreased the amounts of ROS, as compared to $Pam_3CSK_4$ alone, indicating the possibility that P. gingivalis survives within neutrophils. However, neutrophils efficiently killed phagocytosed bacteria of both species despite the absence of $Pam_3CSK_4$. Although P. gingivalis is poorly phagocytosed even by the TLR2-activated neutrophils, TLR2 activation of neutrophils may help to reduce the colonization of P. gingivalis by efficiently eliminating S. sanguinis, an early colonizer, in subgingival biofilm.

• Environmental Engineering Research
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• 제20권2호
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• pp.141-148
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• 2015

The presence of phenols in treated palm oil mill effluent (POME) is an environmental concern due to their phytotoxicity and antimicrobial activity. In this study, phenol-degrading bacteria, Methylobacterium sp. NP3 and Acinetobacter sp. PK1 were immobilized on oil palm empty fruit bunches (EFBs) for removal of phenols in the treated POME. The bacterial exopolysaccharides (EPS) were responsible for cell adhesion to the EFBs during the immobilization process. These immobilized bacteria could effectively remove up to 5,000 mg/L phenol in a carbon free mineral medium (CFMM) with a greater degradation efficiency and rate than that with suspended bacteria. To increase the efficiency of the immobilized bacteria, three approaches, namely activation, acclimation, and combined activation and acclimation were applied. The most convenient and efficient strategy was found when the immobilized bacteria were activated in a CFMM containing phenol for 24 h before biotreatment of the treated POME. These activated immobilized bacteria were able to remove about 63.4% of 33 mg/L phenols in the treated POME, while non-activated and/or acclimated immobilized bacteria could degrade only 35.0%. The activated immobilized bacteria could be effectively reused for at least ten application cycles and stored for 4 weeks at $4^{\circ}C$ with the similar activities. In addition, the utilization of the abundant EFBs gives value-added to the palm oil mill wastes and is environmentally friendly thus making it is attractive for practical application.

• 미생물학회지
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• 제37권1호
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• pp.85-91
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• 2001

생물학적 방법으로 토착 미생물에 의해 벤젠과 톨루엔을 효과적으로 분해할 수 있는 토양환경인자의 조건을 조사하기 위해 16가지의 서로 다른 환경의 미소환경(microcosm)을 제작하여 벤젠과 톨루엔 분해실험을 수행하였고, 아울러 분해과정에서 토착미생물의 분포변화를 조사하였다. 그 결과 실험 조건중 토양의 수분 포화도는 30%와 60%이면서 동시에 생물들이 흡착할 수 있는 미생물 흡착제로 활성탄을 1% 첨가한 미소환경(Case 6, Case 7)에서 벤젠과 톨루엔의 분해속도가 가장 빨랐다. 토착토양미생물의 분포변화를 조사한 결과 벤젠과 톨루엔의 분해가 가장 빨리 일어나는 Case 6 와 Case 7에서는 10일 배양 후 total culturable bacteria는 초기 세균 수에 비해 각각 488배와 308배가 증가하였다. 벤젠과 톨루엔 분해세균의 증가 역시 총 세균수가 증가하는 비율로 증가하여 초기 분포를 계속 유지하였고, 벤젠과 톨루엔을 첨가한 미소환경에서 분해 미생물 종의 변화는, 첨가 전 그람음성 세균이 반응 10일 후에는 그람양성 세균이 탈이 분리되었다.

• Journal of Microbiology and Biotechnology
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• 제21권3호
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• pp.284-292
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• 2011

An endocellulase-free multienzyme complex was produced by a thermophilic anaerobic bacterium, Thermoanaerobacterium thermosaccharolyticum strain NOI-1, when grown on xylan. The temperature and pH optima for growth were $60^{\circ}C$ and 6.0, respectively. The bacterial cells were found to adhere to insoluble xylan and Avicel. A scanning electron microscopy analysis showed the adhesion of xylan to the cells. An endocellulase-free multienzyme complex was isolated from the crude enzyme of strain NOI-1 by affinity purification on cellulose and Sephacryl S-300 gel filtration. The molecular mass of the multienzyme complex was estimated to be about 1,200 kDa. The multienzyme complex showed one protein on native PAGE, one xylanase on a native zymogram, 21 proteins on SDS-PAGE, and 5 xylanases on a SDS zymogram. The multienzyme complex consisted of xylanase, ${\beta}$-xylosidase, ${\alpha}$-L-arabinofuranosidase, ${\beta}$-glucosidase, and cellobiohydrolase. The multienzyme complex was effective in hydrolyzing xylan and corn hulls. This is the first report of an endocellulase-free multienzyme complex produced by a thermophilic anaerobic bacterium, T. thermosaccharolyticum strain NOI-1.

• International Journal of Oral Biology
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• 제42권1호
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• pp.25-31
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• 2017

Dental caries is the most common chronic disease in the dental field. Streptococcus mutans (S. mutans) is the most important bacteria in the formation of dental plaque and dental caries. In a previous study, we confirmed that the essential oil of Chrysanthemum boreale has antibacterial activity against S. mutans. Alpha-pinene is one of the major chemical components of Chrysanthemum boreale essential oil. In the present study, we investigated the inhibitory effects of ${\alpha}-pinene$ on cariogenic properties such as growth, acid production, biofilm formation, and bactericidal activity on S. mutans. Alpha-pinene at a concentration range of 0.25-0.5 mg/mL significantly inhibited the growth of S. mutans and acid production of S. mutans. Biofilm formation was significantly inhibited at > 0.0625 mg/mL ${\alpha}-pinene$, similar to the data from scanning electronic microscopy. Under confocal laser scanning microscopy, the bacterial viability was decreased by ${\alpha}-pinene$ in a dose-dependent manner. These results suggested that ${\alpha}-pinene$ may be a useful agent for inhibiting the cariogenic properties of S. mutans.

• 한국염색가공학회지
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• 제30권4호
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• pp.245-255
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• 2018

In this study, cotton fabrics were coated with $TiO_2$ nanoparticles using 3-mercaptopropyltrimethoxysilane(3-MPTMS), which is highly reactive to cotton fabrics, as a medium, and the characteristics, antimicrobial properties, and photodegradation properties of the fibers were measured. The manufacturing process is as follows. (1) 3-MPTMS was added to isopropanol, and $TiO_2$ colloid was added to the mixture to prepare a solution. (2) Cellulose fibers were immersed in the prepared $3-MPTMS/TiO_2$ solution, stirred for 90 minutes at $45^{\circ}C$ in a constant temperature water bath, and dried thereafter. In order to identify the morphology of the cellulose fibers coated with $TiO_2$ nanoparticles, the surface was observed with a scanning electron microscope(SEM), and SEM-EDS was measured to identify the adhesion of $TiO_2$ nanoparticles. The SEM images showed $TiO_2$ nanoparticle and 3-MPTMS coated layers on the fibers and it was identified that $TiO_2$ nanoparticles were attached to the cellulose fibers. The antimicrobial activity of $3-MPTMS/TiO_2$-treated cotton fabrics was measured using a bacterial reduction method. $3-MPTMS/TiO_2$ cellulose fibers which was irradiated by ultra violet light, showed antimicrobial activity against Escherichia coli(ATCC 43895) and Staphylococcus aureus(ATCCBAA-1707) unlike unirradiated fibers. The cellulose fibers were stained with methylene blue and the photodegradation performance of the stained fabrics was analyzed. The stained fabrics showed high degradation performance with photolytic reactions of $TiO_2$ nanoparticles.

• Journal of Veterinary Science
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• 제19권6호
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• pp.808-816
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• 2018

Bacterial biofilms have been demonstrated to be closely related to clinical infections and contribute to drug resistance. Berberine, which is the main component of Coptis chinensis, has been reported to have efficient antibacterial activity. This study aimed to investigate the potential effect of a combination of berberine with ciprofloxacin (CIP) to inhibit Salmonella biofilm formation and its effect on expressions of related genes (rpoE, luxS, and ompR). The fractional inhibitory concentration (FIC) index of the combination of berberine with CIP is 0.75 showing a synergistic antibacterial effect. The biofilm's adhesion rate and growth curve showed that the multi-resistant Salmonella strain had the potential to form a biofilm relative to that of strain CVCC528, and the antibiofilm effects were in a dose-dependent manner. Biofilm microstructures were rarely observed at $1/2{\times}MIC/FIC$ concentrations (MIC, minimal inhibition concentration), and the combination had a stronger antibiofilm effect than each of the antimicrobial agents used alone at $1/4{\times}FIC$ concentration. LuxS, rpoE, and ompR mRNA expressions were significantly repressed (p< 0.01) at $1/2{\times}MIC/FIC$ concentrations, and the berberine and CIP combination repressed mRNA expressions more strongly at the $1/4{\times}FIC$ concentration. The results indicate that the combination of berberine and CIP has a synergistic effect and is effective in inhibiting Salmonella biofilm formation via repression of luxS, rpoE, and ompR mRNA expressions.

• 한국산학기술학회논문지
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• 제22권1호
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• pp.562-567
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• 2021

다양한 건축시설 및 생활제품에 적용하기 위한 기능성 항균강화유리개발을 위해 국산 소재들의 항균력을 조사하여, 특정농도에서 99% 이상의 항균력을 갖는 은, 구리, 아연으로 강화유리 시편을 제작하였다. 은, 구리, 아연을 Ethylene glycol + Glycerol로 분산시킨 시편의 항균력은 모두 99% 이상으로 측정되었고, Ethylene glycol과 Glycerol을 단독으로 사용했을 때는 항균력이 감소되었다. 표면분석기를 사용하여 세척에 의한 결합된 금속소재의 두께 변화를 측정한 결과, 물을 포함한 다양한 종류의 세제로 세척한 시편에서는 표면에 도포된 소재의 두께가 1% 미만으로 감소하였지만, 염기성 세제에서는 약 10%의 표면두께 감소가 확인되었다. 또한, 시편의 인체 안전성을 확인하기 위해, MTT 분석법을 통한 세포독성실험을 수행하였고, 항균물질들이 도포된 시편에서의 세포독성은 대조군과 비교하였을 때 거의 나타나지 않았다. 마지막으로, 시제품의 항균력이 99% 이상임을 Bacterial Live/dead kit을 이용하여 확인하였고, 공인인증기관의 필름밀착법으로 다시 한 번 시제품의 항균력을 검증하였다. 결국, 본 연구에서는 국산소재들의 항균력을 검증과 함께 이를 이용한 고기능성 항균효과 갖는 강화유리를 개발하였다.

• Journal of Periodontal and Implant Science
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• 제52권2호
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• pp.116-126
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• 2022

Purpose: This study evaluated the efficacy of treating periodontitis using subgingival nano-hydroxyapatite powder with an air abrasion device (NHAPA) combined with scaling and root planing (SRP). Methods: A total of 28 patients with stage III periodontitis (grade B) were included in this study, although 1 was lost during follow-up and 3 used antibiotics. The patients were divided into a test group and a control group. All patients first received whole-mouth SRP using hand instruments, and a split-mouth approach was used for the second treatment. In the test group, the teeth were treated with NHAPA for 15 seconds at 70% power per pocket. Subgingival plaque samples were obtained from the 2 deepest pockets at the test and control sites before treatment (baseline) and 3 months after treatment. The full-mouth plaque index (PI), gingival index (GI), papillary bleeding index (PBI), bleeding on probing (BOP), probing depth (PD) and clinical attachment level (CAL) were recorded at baseline and at 1- and 3-month post-treatment. Real-time polymerase chain reaction was used to determine the colonisation of Treponema denticola (Td), Porphyromonas gingivalis (Pg), and Aggregatibacter actinomycetemcomitans in the subgingival plaque. Results: From baseline to the first month, the test group showed significantly larger changes in BOP and CAL (43.705%±27.495% and 1.160±0.747 mm, respectively) than the control group (36.311%±27.599% and 0.947±0.635 mm, respectively). Periodontal parameters had improved in both groups at 3 months. The reductions of PI, GI, BOP, PD, and CAL in the test group at 3 months were greater and statistically significant. The total bacterial count and Td and Pg species had decreased significantly by the third month in both groups (P<0.05). Conclusions: Applying NHAPA in addition to SRP improves clinical periodontal parameters more than SRP alone. Subgingival NHAPA may encourage clot adhesion to tooth surfaces by increasing surface wettability.