• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.503-508
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• 2009

We investigated species composition and variation of benthic marine algae between 2003 and 2006 at Dokdo on the East Sea. The total number of benthic algae species identified was 96, which included 15 Chlorophyta, 30 Phaeophyta, 50 Rhodophyta and 1 Spermatophyta species. The representative species in this study were Ulva pertusa, Caulerpa okamurae, Codium adhaerens, C. frgile, Undaria pinnatifida, Ecklonia cava, Eisenia bicyclis, Dictyopteris undulata, Padina arborescens, Sargassum horneri, Hildenbrandtia rubra, Lithophyllum okamurae, Amphiroa dilatata, Corallina officinalis, C. pilulifera, Prionitis cornea, Grateloupia elliptica, Plocamium telgairiae, Chondrus ocellatus, Chondracanthus intermedia, Chondria crassicaulis, Polysiphonia morrowii, Melobesioidean algae and Phyllospadix sp. Wet weight biomass according to various depths ranged between 1,094.8 to $2,595.3\;g\;m^{-2}$ during the study period. Mean biomass at the investigated sites was greater in the 15m depth range than in the 5 and 10m depths. Vertical distribution was characterized by Ulva intestinalis, U. linza, Endarachne binghamiae, Bangia atropurpurea, Gloiopeltis furcata and Chondria crassicaulis at intertidal zone, Amphiroa dilatata, Corallina pilulifera, Gelidium amansii, Eisenia bicyclis and Ecklonia cava at 2m depth, Ecklonia cava, Eisenia bicyclis, Padina arborescens, Undaria pinnatifida and Sargasum horneri at 5m depth, Ecklonia cava, Sargassum horneri and Padina arborescens at 10m depth, Ecklonia cava, Myagropsis myagroides, Padina arborescens and Sargassum horneri at 15m depth. The R/P, C/P and (R+C)/P value were 1.67, 0.50 and 2.17, respectively.

• ALGAE
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• v.23 no.4
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• pp.317-326
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• 2008

Marine algal flora and community structure were investigated seasonally at three sites in Ilkwang Bay on the southern east coast of Korea from May 2007 to February 2008. Total 103 species including 10 of green algae, 17 of brown algae, 76 of red algae were collected and identified. Among these species, 21 species were found throughout the year. Ulva pertusa, Enteromorpha linza, Grateloupia lanceolata, Chondracanthus intermedia and Caulacanthus ustulatus were distributed dominantly in upper intertidal zone. By contrast, crustose coralline algae, Grateloupia spp., Chondracanthus tenellus, Prionitis cornea and Sargassum spp. occurred predominantly in middle intertidal zone. Grateloupia spp., Sargassum spp., Ecklonia cava and Ulva pertusa were dominant in lower intertidal zone. Annual mean biomass in wet weight was 478.3 g m$^{-2}$. Maximum biomass was recorded in site 1 (731.8 g m$^{-2}$), and minimum was recorded in site 3 (78.5 g m$^{-2}$). The R/P, C/P and (R + C)/P value reflecting flora characteristics were 4.47, 0.59 and 5.06, respectively. Two groups produced by cluster analysis, one including sites 1, 2 and the other including site 3, showed meaningful difference in similarity, each other. Site 3 showed the limited species composition due to inflow of fresh water and absence of solid substratum. However, there was no significant difference between site 1 and site 2. In conclusion, the number of marine algae species and biomass in Ilkwang Bay were markedly reduced comparing with the previous studies. These suggest that a solution for reconstruction of the poor marine algal vegetation is considerably demanded.

• Journal of Periodontal and Implant Science
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• v.50 no.6
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• pp.358-367
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• 2020

Purpose: The aim of this study was to investigate the efficacy and validity of subgingival bacterial sampling using a retraction cord, and to evaluate how well this sampling method reflected changes in periodontal conditions after periodontal therapy. Methods: Based on clinical examinations, 87 subjects were divided into a healthy group (n=40) and a periodontitis group (n=47). Clinical measurements were obtained from all subjects including periodontal probing depth (PD), bleeding on probing (BOP), clinical attachment loss (CAL), and the plaque index. Saliva and gingival crevicular fluid (GCF) as a subgingival bacterial sample were sampled before and 3 months after periodontal therapy. The salivary and subgingival bacterial samples were analyzed by reverse-transcription polymerase chain reaction to quantify the following 11 periodontal pathogens: Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythus (Tf), Treponema denticola (Td), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn), Pavimonas micra (Pm), Campylobacter rectus (Cr), Prevotella nigrescens (Pn), Eikenella corrodens (Ec), and Eubacterium nodatum (En). Results: Non-surgical periodontal therapy resulted in significant decreases in PD (P<0.01), CAL (P<0.01), and BOP (P<0.05) after 3 months. Four species (Pg, Tf, Pi, and Pm) were significantly more abundant in both types of samples in the periodontitis group than in the healthy group. After periodontal therapy, Cr was the only bacterium that showed a statistically significant decrease in saliva, whereas statistically significant decreases in Cr, Pg, and Pn were found in GCF. Conclusions: Salivary and subgingival bacterial sampling with a gingival retraction cord were found to be equivalent in terms of their accuracy for differentiating periodontitis, but GCF reflected changes in bacterial abundance after periodontal therapy more sensitively than saliva.

• Journal of Korean Academy of Oral Health
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• v.41 no.4
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• pp.290-295
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• 2017

Objectives: Dental plaque emits red fluorescence under a visible blue light near the ultra-violet end of the light spectrum. The fluorescence characteristics of each microorganism have been reported in several studies. The aim of this study was to evaluate changes in red fluorescence of oral microorganisms that is affected by blood in the culture media. Methods: The gram-positive Actinomyces naeslundii (AN, KCTC 5525) and Lactobacillus casei (LC, KCTC 3109) and gram negative Prevotella intermedia (PI, KCTC 3692) that are known to emit red fluorescence were used in this study. Each bacterium was activated in broth and cultivated in different agar media at $37^{\circ}C$ for 7 days. Tryptic soy agar with hemin and vitamin $K_3$ (TSA), TSA with sheep blood (TSAB), basal medium mucin (BMM) medium, and BMM with sheep blood (BMMB) were used in this study. Fluorescence due to bacterial growth was observed under 405-nm wavelength blue light using the quantitative light-induced fluorescence-digital (QLF-D) device. The red, green, and blue fluorescence values of colonies were obtained using image-analysis software and the red to green ratio (R/G value) and red to total RGB ratio (R/RGB value) were calculated for quantitative comparison. Results: The QLF-D images of the AN, LC, and PI colonies showed red fluorescence in all media, but the fluorescence of all bacteria was reduced in TSA and BMM media, compared with in TSAB and BMMB media. Both the R/G and the R/RGB values of all bacteria were significantly reduced in growth media without blood (P<0.001). Conclusions: Based on this in vitro study, it can be concluded that red fluorescence of oral bacteria can be affected by growth components, especially blood. Blood-containing medium could be a significant factor influencing red fluorescence of oral bacteria. It can be further hypothesized that bleeding in the oral cavity can increase the red fluorescence of dental plaque.

• Restorative Dentistry and Endodontics
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• v.26 no.2
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• pp.141-152
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• 2001

Eliminating the infecting bacteria of the root canal system and preventing reinfection must be the main objectives of all endodontic works. None of commercially available root canal sealers have the properties of desirable tissue compatibility and strong antibacterial activity. The purpose of this study is to develope an ideal root canal sealer using commercially available polyphosphate (polyP), Calgon, which is known to be antibacterial and safe. For the study. resin type AH26, zinc oxide eugenol type Tubli Seal. Ca(OH)$_2$ type Apexit as base sealers for polyP (0~3%) and para formaldehyde containing N2 as a control base were selected. Specimens (3$\times$4mm) of the sealers were prepared in a 37$^{\circ}C$ incubator for 3 and 10 days and their antibacterial activity against streptococci and black pigmented anaerobic rods was observed using an agar diffusion method. The result were as follows: 1. Among 3 day old root canal sealers. N2 as a positive control showed the strongest antibacterial effect. followed by AH26. Tubli Seal and. Apexit which barely showed antibacterial activity against the test bacteria. In contrast. 10 day old AH26 showed a greater antibacterial activity than 10 day old N2. 2. All sealer specimens showed a greater antibacterial activity against black pigmented anaerobic rods than streptococci. Three day old ones appeared to be more antibacterial than 10 day old ones except for Apexit. 3. As compared to N2, 3 day old AH26 demonstrated a similar antibacterial activity against black pig mented anaerobic rods but to a lesser extent to streptococci. Ten day old AH26 showed a greater antibacterial activity against black pigmented anaerobic rods than 10 day old N2. 4. As compared to AH26. Tubli Seal generally revealed a lower antibacterial activity but it showed a greater antibacterial activity aginst S. gordonii Challis. 5. Enhancement of antibacterial activity by polyP was more clearly observed when it was added to Ca(OH)$^{\circ}C$ based root canal sealers. Tubli Seal and N2. 6. The addition of polyP enhanced the antibacterial activity of 3 day old AH26 against S. gordonii G9B (16%) and Challis (29%), and P. gingivalis 2561 (24%) only. Moreover, polyP failed to increase antibacterial activity of 10 day old AH26 against the test strains but P. gingivalis A7A1 28(13%). 7. The addition of polyP increased the antibacterial effect of 3 day old Tubli Seal on several test bacteria including s. mutans GS 5 (50%). s. gordonii G9B (47%) and Challis (122%). and all the test strains of P. gingivalis (13~35%) except for 9 14K 1. The addition of polyP to 10 day old Tubli Seal increased antibacterial activity of the root canal sealer against most test strains. 8. 3 day old Apexit failed to show antibacterial activity. if any very little against S. mutans GS 5 and Pr. intermedia ATCC 49046. However. polyP increased its antibacterial activity by 50 and 69%, respectively. Increase of antibacterial activity of 10 day old Apexit by polyP was more clearly observed than that of 3 day old one.

• Journal of Periodontal and Implant Science
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• v.33 no.3
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• pp.341-348
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• 2003

The purpose of this study was to determine the minimal inhibitory concentration (MIC) of cefuroxime axetil,　semisynthetic cefalosporin, for some putative periodotopathogens; F. nucleatum, A. actinomycetemcomitans P. intermedia and P. gingivalis. To investigate the efficacy of cefuroxime axetil, several antibiotics, amoxicillin, metronidazole, and ciprofoxacine, were used as control. The MIC was measured by Murray' s method. The MIC of cefuroxime axetil against some putative microbes, as a single use regimen, was relatively high in comparison with that of the other antibiotics used in this study. The MIC of cefuroxime axetil/metronidazole against some putative microbes, as a simultaneous regimen, was similar to that of the other antibiotics used in this study. The manimal level of cefuroxime concentration in gingival fluid was 9${\mu}$/ml at 36hr after the first dose. In conclusion, within the limited experiment, metronidazole/ cefuroxime axetil therapy of periodontitis may provide a therapeutic benefits in reducing the periodontopathogens.

• Journal of Periodontal and Implant Science
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• v.23 no.1
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• pp.145-158
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• 1993

The oral microbiota such as P. gingivalis, P. intermedia and A. actinomycetemcomitans play a primary role in the initiation and progression of the periodontal disease. The purpose of this study was to evaluate the antimicrobial effects and inhibitory effects of honokiol and magnolol on the bacterial collagenase activity, cytotoxicity and cytokine production of periodontopathic microorganisms. The antimicrobial activities of honokiol and magnolol was evaluted with minimum inhibition concentration. Honokiol was more active than magnolol, but less than chlorhexidine on antimicrobial activity. The inhibitory effects of magnolol and honokiol on the collagenolytic activity and cytotoxicity were evaluated using a Collagenokit CLN-100 and rapid colorimetric assay (MTT method) for cellular growth and survival of gingival fibroblast and periodontalligament cell and $[^3H]-thymidine$ incorporation for the gingival epithelial cell. The inhibitory effects on the collagenolytic activity was the highest in chlorhexidine, and the lowest in magnolol. Magnolol had the lowest cytotoxic effect and chlorhexidine had the highest. The inhibitory effects on cytokine production was evaluated using $interleukin-1{\beta}$ ELISA kit (Cistron Biotech.), IL-6, $TNF-{\alpha}$ ELISA kit (Genzyme) and inhibitory effects were higher than bacterial LPS and there is no difference among the honokiol, magnolol and chlorhexidine. From these results, the antimicrobial and antienzymatic activities of honokiol and magnolol were seemed to inhibit bacterial growth and enzyme activities with lesser cytotoxic activities. Therefore, it was suggested that honokiol and magnolol are very effective antimicrobial agents on periodontal pathogens.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.2
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• pp.1-12
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• 2017

This study aims to provide the basic habitat data for the alternative breeding sites of Family Ardeidae including Ardea cinerea, Egretta alba modesta, Egretta intermedia, Egretta garzetta, Bubulcus ibis and Nycticorax nyciticorax. Species numbers, flight directions for detecting foraging grounds and current vegetation structure were investigated nesting at Gunsan urban forest area. Data were collected over a period of 10 weeks, from 15 June - 31 August 2014. The total nest and population of Family Ardeida were 684 and 1,712 respectively. Percentage of birds observed flying in 8 major compass directions were as follows. 57.27% of all birds were observed flying northwest, 22.09% were observed flying south and 13.40% were flying north. For possible foraging areas, to the northwest, there are Geumgang river tidal flats, and to the south, paddy fields and streams within 2km. Flying directions by species (${\chi}^2=287.18$, P<.001, Cramer's V=0.12) and by seasons(${\chi}^2=839.94$, P<.001, Cramer's V=0.19) showed significant difference statistically. In relation between species and directions, 60.31% and 24.05% of Bubulcus ibis and 59.40% and 23.00% of Ardea cinerea were observed flying northwest and south respectively. Vegetation in the sites consist of an overstory of 3 to 7 species. At site 1, Pinus thunbergii was the dominant species and site 2, Chamaecyparis obtusa. Understory vegetation is composed of shrubs, saplings and small trees of Chamaecyparis obtusa, Quercus acutissima, Smilax china and Platycarya strobilacea. Egrets and herons usually nested at the dense population and canopy overlayed forest, and especially branches and leaves of smallwood with less than 10cm of breast height diameter were relatively severely damaged due to the nesting and excreta.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.141-150
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• 1998

This study was performed to investigate the distribution of Yersiniae and correlation between Yersiniae and indicator organism by time and area in spring water located in northern part of Seoul. Samples collected from 46 spring waters located in four mountains(Dobong, Bukhan, Surak, Bulam) were inspected to detect Yersiniae and indicator organisms. And also there were examined bioserological characteristics and resistance of ahtibiotics of the isolated Yersiniae.The result were as follows. 1. The isolation rate of Yersiniae was 22% in February and 20% in April. The isolated species were 6 strains of Y. enterocolitica, 6 strains of Y. aldova, 4 strains of Y. intermedia and 43 strains of Y. pseudotuberculosis. The serotype of Y. pseudotuberculosis isolated from was all O:5 and biotype of Y. enterocolitica isolated from was all O:3. 2. The Geometric mean of standard plate count, coliform, and psychrotrophilic bacteria were 3.4 CFU/ml, 1.2 MPN/100 ml and 33.0 CFU/ml in February and 3.1 CFU/ml, 1.5 MPN/100 ml and 20.5 CFU/ml in April respectively. There was no significant difference by time and area but the indicator organisms were correlated significantly with each other (p<0.05). 3. Because detection of Yersiniae was not statistically associated with indicator organism, Yersiniae can be detected in the spring water approved microbiologically (p<0.05). 4. The Yersiniae isolated were resistant to Ampicillin, Colistin, Carbenicillin and Coilstin. All isolaed Y. enterocolitica were resistant to Ampicillin (100%). In the case of Y. pseudotuberculosis, only 1 of 3 isolated was resistant to Colistin but susceptible to other antibiotics.

• Journal of Periodontal and Implant Science
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• v.27 no.4
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• pp.723-737
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• 1997

본 연구의 목적은 조직유도재생술의 초기치유시에 구강양치액으로 사용되어지는 0.1% 클로르헥시딘과 0.2% 클로르헥시딘을 사용했을 경우, 양치액을 사용하지 않았을 경우의 세균감염 정도를 비교하는 것이다. 30명의 성인형 치주염에 이환되어진 사람을 대상으로 하였다. 초기치료(Scaling/Root planing/Oral hygiene instruction)를 시행한 후에 한 사람에 한 군데씩 선정하여 2급이나 3급의 치근이개부를 가지고 임상적으로 혹은 방사선학적으로 치간골내낭을 보이지 않는 치아에 통법에 따라 Gore-TexTM를 위치시켰다. 술후 5일간 항생제 (UnasynTM 375mg tablet p.o.tid)를 투여하고 차폐막을 제거할 때까지(4주 혹은 6주) 10명의 환자에게는 0.1% 클로르헥시딘을, 다른 10명의 환자에게는 0.2% 클로르헥시딘으로 구강양치를 하게 하고, 또 다른 10명의 환자에게는 구강양치액을 사용하지 않도록 하였다. 또 1주일에 한번씩 전문가구강위생술식을 실시하였다. 4주나 6주 후에 차폐막을 제거하고 주사전자현미경, 혐기성 세균배양을 이용하여 세균감염정도를 비교하였다. 1. 주사전자현미경으로 관찰시에 0.1% 클로르헥시딘을 사용했을 경우와 0.2% 클로르헥시딘을 사용했을 경우, 클로르헥시딘을 사용하지 않은 경우에 별 차이를 발견할 수 없었다. 2. 혐기성 세균배양시에 0.2% 클로르헥시딘을 사용했을 경우, 0.1%클로르헥시딘을 사용했을 경우보다 적은 수의 세균 수를 보였으나 통계적으로 유의할 만한 차이는 보이지 않았다. 클로르헥시딘을 사용하지 않은 경우에는 다른 두 경우에 비해 통계적으로 유의할 만한 차이를 보였다.(P<0.05) 3. Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia를 인지한 경우에는 세 경우 모두 비슷한 비율로 발견되었다.