• Journal of Periodontal and Implant Science
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• 제23권1호
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• pp.109-126
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• 1993

Refractory periodontitis manifest progressive attachment loss in a rapid and unrelenting manner regardless of the type or frequency of therapy applied. The purpose of this study was ta evaluate the relation between the level of cytokines in GCF and periodontopathic microflora with disease activity of refractory periodontitis. Selection of patients with refractory periodontitis (7 males, 3 females) were made by long term clinical observation including conventional clinical history and parameters. Teeth that showed pocket depth greater than 6mm were selected as sample teeth. Subjects were examined at baseline and after 3 months. Prior to baseline test, individual acrylic stent was fabricated. Reference grooves were made on each sample tooth site. Pocket depth and attachment loss were measured by Florida Probe. Gingival index was measured at 4 sites each sample teeth. Disease activity was defined as attachment loss of ${\ge}$ 2.1mm, as determined by sequential probing and tolerance method. The pattern and amount of alveolar bone resorption was observed with quantitative digital subtraction image processing radiography. Morphological analysis of subgingival bacteria was taken by phase contrast microscopy. Predominant cultivable bacterial distribution and frequency were compared between disease-active and disease-inactive site using immunofluorescence microscopy and selective microbial culturing. Levels of $interleukin-l{\beta}$, 2, 4, 6 and $TNF-{\alpha}$ in GCF and blood serum sample were quantified by ELISA. In active sites, P. intermedia was significantly increased to compare with inactive site. $IL-1{\beta}$, IL-2, IL-6 and $TNF-{\alpha}$ in GCF were increased in active sites and IL-2 in serum was increased in active patients significantly. Alveolar bone loss in active site was correlated with $IL-1{\beta}$, IL-2 in GCF. And loss of attachment in active site was correlated with IL-2 in GCF. These results demonstrate that IL-2 in serum, $IL-1{\beta}$, IL-2, IL-6 and $TNF-{\alpha}$ in GCF, P, intermedia might be used as possible predictors of disease activity in refractory periodontitis before it is clinically expressed as attachment loss and quantitative alveolar bone change.

• 대한소아치과학회지
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• 제30권1호
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• pp.69-79
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• 2003

자가중합형 아크릴릭 레진에 polyp를 혼합하지 않은 대조군, 그리고 레진 분말에 대한 polyP(사슬길이 13과 18의 혼합물인 Calgon)의 무게비를 1%로 혼합한 polyP 1%군, 2% 혼합한 polyP 2%군 및 3% 혼합한 polyP 3%군으로 분류하여 경화시킨 후, 경화된 각각의 레진과 실험균주 S. mutans GS5, S. sobrinus 6715, S. gordonii G9B및 Challis, 그리고 P. gingivalis 2561과 Candida albicans ATCC90027을 대상으로 레진표면에 대한 미생물들의 부착의 정도, 성장 억제효과 및 접촉각의 변화를 관찰하여 그 결과로 미루어 아크릴릭 레진에 포함된 polyP는 구강 미생물에 대해 직접적으로 강한 항균 효과를 나타내지는 않는 것으로 판단되나 미생물의 부착 특히 우식원인균인 mutans streptococci의 부착을 방해하는 것으로 가늠되며, 이는 polyP의 첨가에 의한 아크릴릭 레진 표면에서 일어난 소수성의 변화가 일부 관여하는 것으로 여겨진다. PolyP가 혼합된 아크릴릭 레진의 장착은 일반적인 아크릴릭 레진으로 제작된 가철성 장치를 장착한 후 나타날 수 있는 우식 이환의 가능성을 감소시킬 수 있는 임상적 적용 가능성을 제시하였다고 여겨진다.

• 한국응용곤충학회지
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• 제29권4호
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• pp.252-256
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• 1990

담배거세미나방 핵다각체병바이러스를 white carbon 제제, molasses 제제 및 White carbon-molasses 혼합제등 3종의 바이러스살충제로 만들어 제제의 살포방법, 살포효과 및 잔류효과를 폿트 및 콩포장에서 살충효과를 비교하였다. 바이러스 살충채 살포는 콩잎 표면 살포시 약 5일, 이변 살포시 약 12일까지 60% 이상의 살충효과가 지속되었다. 폿트식재 콩잎을 이용한 바이러스살충제의 살포효과는 molasses 제제와 with carbon 제제에서 모두 97% 이상의 살충효과가 있었으나 molasses성분을 포함한 제제는 햇빛에 의해 일부 콩잎에 약해를 보였다. 바이러스살충제 살포 1 시간 후 빗물 처리에 의한 영향은 빗물 무처리와 큰 차이가 없이 90% 이상의 살충효과가 있었다. 야외 콩 포장에서 바이러스살충제의 살포효과는 3종의 제제 모두 90%이상의 살충율이었 며, 유기합성농약보다 7일 늦게 효과가 나타난 반면 2주 이상 효과가 지속되었다.

• Journal of Periodontal and Implant Science
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• 제33권2호
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• pp.247-257
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• 2003

The purpose of this study was to evaluate the difference of subgingival bacterial compositions between periodontally healthy and diseased sites. Subgingival plaque samples were obtained from 100 sites in 20 untreated adult periodontitis patients(experimental group), and 100 sites in healthy individuals(contro1 group). Before sampling, probing pocket depth(PPD) and clinical level of attachment(CAL), Plaque Index(PI), and Sulcus Bleeding Index(SBI) were recorded for each sampled sites. Microbial samples were collected from the bases of gingival sulci or periodontal pockets with sterile curettes. The samples were examined under darkfield microscope(${\times}$400). At least 150 bacteria were evaluated and categorized on the basis of bacterial morphology and motility, i.e. cocci, non-motile rods, motile rods, and spirochetes. In control group, subgingival microbial flora consisted of 73.7% of cocci, 20.0% of non-motile rods, 4.3% of motile rods, and 2.0% of spirochetes. The microbial samples from experimental group consisted of 51.5% of cocci, 19.4% of non-motile rods, 17.6% of motile rods, and 11.6% of spirochetes. The proportion of cocci was higher in control group than in experimental group. Proportions of motile rods and spirochetes were higher in experimental group than in control group. The proportion of nonmotile rods in experimental group and control group was not significantly different. Sulcus Bleeding Index and Plaque Index showed high correlation with the bacterial composition. These findings suggests that examination of subgingival bacterial proportion may serve as more sensitive mirror of the local periodontal status than clinical parameters.

• 상하수도학회지
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• 제18권5호
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• pp.649-655
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• 2004

The behavior of biological particles in DAF (dissolved air flotation) process was analyzed by employing PBT (Population balance theory). After decline growth phase of activated sludge, the value of the initial collision-attachment efficiency was increased over than 0.35 corresponding relatively high value in the whole life cycle of microorganism. For practical application of DAF as a solid separation process. It is desirable that microbial particles should be operated to perform high solid removal efficiency in biological wastewater treatment.

• International Journal of Oral Biology
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• 제35권4호
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• pp.197-202
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• 2010

Most oral microorganisms exist as biofilms which initiate formation via the attachment of an early colonizer to host proteins on the tooth surface. Fusobacterium nucleatum act as a bridge between early and late colonizers. Dental biofilms eventually comprise dental pathogens such as Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia. To evaluate the effects of mutual interactions between oral bacteria on the growth of biofilms, periodontopathogens were co-cultured with a $0.4\;{\mu}m$ barrier. Streptococcus gordonii inhibited the growth of F. nucleatum and periodontopathogens. However, F. nucleatum, P. gingivalis and T. denticola activated the growth of other bacteria. A co-culture system of early and late colonizers could be a useful tool to further understand bacterial interactions during the development of dental biofilm.

• 한국식품위생안전성학회지
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• 제28권3호
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• pp.272-278
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• 2013

본 연구는 polyvinyl chroride (PVC)와 stainless steel 표면에서 E. coli O157:H7의 부착, 바이오필름형성, 온 습도에 따른 생존율을 조사하고, E. coli O157:H7이 오염된 작업대 표면에서 상추로의 교차오염도 조사를 통하여 E. coli O157:H7에 오염된 작업대가 상추의 미생물학적 안전성에 미치는 영향을 평가하고자 수행하였다. 작업대 표면 재질인 PVC와 stainless steel에 E. coli O157:H7 배양액을 1시간 노출시켰을 때, PVC의 경우, stainless steel 보다 10배 정도 부착력이 높았으나, 6시간째는 두 재질간의 차이가 없었다. 또한, E. coli O157:H7의 바이오필름 형성은 TSB > 10% 상추추출액 > 1% 상추추출액 > phosphate buffer 순이었으며, 재질별로는 PVC에서 바이오필름형성능이 높은 것으로 나타났다. 온도 $20^{\circ}C$, $30^{\circ}C$, 습도 43%, 69%, 100%에서 각각 노출 시켰을 때, E. coli O157:H7은 온도 $30^{\circ}C$, 습도 43%, 69% 조건에서 12시간 내에 약 5.0 log CFU/coupon이 감소한데 반해, 상대습도 100%에서는 농도의 큰 변화 없이 5일 이상 생존이 지속되었다. 또한, 유기물이 작업대 표면에 존재 시, E. coli O157:H7의 감소 속도가 느렸다. E. coli O157:H7에 오염된 작업대에 상추를 접촉시키고 상추의 오염도를 조사한 결과, 상추 표면에 수분이 존재할 때 오염된 작업대 표면에서 E. coli O157:H7의 이동수준이 상추에 수분이 없을 때 보다 10배 이상 증가하는 것으로 나타났다. 따라서 E. coli O157:H7에 오염된 작업대는 상추의 안전성에 직접적인 영향을 미칠 수 있어 작업 후에 세척, 소독을 통하여 위생적으로 관리하는 것이 필요하다.

• 대한미생물학회지
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• 제34권5호
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• pp.435-443
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• 1999

Orientia tsutsugamushi is obligate intracellular bacterium that grows within the cytoplasm of the eukaryotic host cells. Therefore capability of the attachment, entry into the host cell and intracellular survival should be critical process for oriential infection. In this study we investigated the cellular invasion mechanism of Orientia tsutsugamushi and the role of transmembrane heparan sulfate proteoglycan, which binds diverse components at the cellular microenvironment and is implicated as host cell receptors for a variety of microbial pathogens. First of all Orientia tsutsugamushi can invade a wide range of nonprofessional phagocytic cells including fibroblast, epithelial cells and endothelial cells of various host species, including Band T lymphocytes. Thus, it was postulated that the attachment of O. tsutsugamushi requires the recognition of ubiquitous surface structures of many kinds of host cells. Treatments with heparan sulfate and heparin inhibited the infection of Orientia tsutsugamushi in dose-dependent manner for L cell, mouse fibroblast, whereas other glycosaminoglycans such as chondroitin sulfate had no effect. Collectively, these findings provide strong evidence that initial interaction with heparan sulfate proteoglycan is required for the oriential invasion into host cells.

• Environmental Engineering Research
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• 제15권2호
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• pp.71-78
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• 2010

To understand the effects of acclimation schemes on the formation of anode biofilms, different electrical performances are characterized in this study, with the roles of suspended and attached bacteria in single-chamber microbial fuel cells (MFCs). The results show that the generation of current in single-chamber MFCs is significantly affected by the development of a biofilm matrix on the anode surface containing abundant immobilized microorganisms. The long-term operation with suspended microorganisms was demonstrated to form a dense biofilm matrix that was able to reduce the activation loss in MFCs. Also, a Pt-coated anode was not favorable for the initial or long-term bacterial attachment due to its high hydrophobicity (contact angle = $124^{\circ}$), which promotes easy detachment of the biofilm from the anode surface. Maximum power ($655.0\;mW/m^2$) was obtained at a current density of $3,358.8\;mA/m^2$ in the MFCs with longer acclimation periods. It was found that a dense biofilm was able to enhance the charge transfer rates due to the complex development of a biofilm matrix anchoring the electrochemically active microorganisms together on the anode surface. Among the major components of the extracellular polymeric substance, carbohydrates ($85.7\;mg/m^2_{anode}$) and proteins ($81.0\;mg/m^2_{anode}$) in the dense anode biofilm accounted for 17 and 19%, respectively, which are greater than those in the sparse anode biofilm.

• Asian-Australasian Journal of Animal Sciences
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• 제5권2호
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• pp.323-327
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• 1992

An experiment was conducted to determine whether there were any apparent differences in the microbial population, colonization pattern and digestion of guinea grass in situ, between cattle and swamp buffalo. Percentage losses in dry matter (DM), nitrogen (N) and neutral detergent fibre (NDF) of guinea grass were significantly (p<0.01) higher when incubated in the rumen of buffalo than in cattle. Buffalo also showed significantly (p<0.05) faster degradation rates than cattle for each grass component (DM, N, DNF). Light microscopy and SEM examination of the incubated grass materials showed that there were no apparent differences in the pattern of bacterial and fungal invasion and colonization of the grass materials between cattle and buffalo. Attachment of bacteria and fungal zoospores on the grass fragments occurred at 15 min after rumen incubation. After 3 h of rumen incubation, dense population of bacteria was observed in the thin-walled mesophyll and parenchyma tissues, whereas root-like fungal rhizoids were observed in both thin-walled and thick-walled cells. By 6 h, eroded zones were apparent in the thin-walled tissues and in thick-walled tissues with profuse rhizoids. After 24. 48 and 72 h of rumen incubation, most thin-walled tissues were degraded leaving mostly the thick-walled tissues. The predominant bacteria were the curved rods resembling Butyrivibrio sp., the thick rods resembling Fibrobacter sp., the diplococcoids resumbling Ruminococcus sp. And spirochetes. Fungi were predominantly those with spherical or oval sporangia. Fusiform sporangia with acuminate apices which resembled Ruminomyces sp. Were of lesser occurrence. Few protozoa were found on the grass fragments at all incubation times.