• 한국산학기술학회논문지
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• 제12권11호
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• pp.4951-4958
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• 2011

본 연구에서는 전 세계적으로 표준화된 전통적 항균제 감수성 검사방법인 CLSI(C linical and Laboratory Standards Institute)디스크 확산법과 디스크 확산법을 이용 해 MIC를 측정할 수 있도록 새롭게 고안된 E-test 방법과 최근 도입된 미량 액체 배지 희석법을 이용한 항균제 감수성 검사 자동화 장비인 MicroScan MICroSTR EP plus panel를 이용한 MIC 측정방법들의 일치도를 비교하여 MicroScan MICroS TREP plus panel 검사방법의 유용성을 관찰하고자 하였다. 대상균주는 2009년 2월부터 8월까지 6개월 동안 대전의 한 대학병원 임상환자에서 분리된 폐렴사슬알균 53균주와 알파용혈 사슬알균 51균주를 대상으로 하였으며 항 균제는 cefotaxime, chloramphenicol, clindamycin, erythromycin, levofloxacin, penicillin, tetracycline, trimethoprim/sulfamethoxazole, vancomycin 등 9가지 항균제를 평가 대상으로 하였다. 폐렴사슬알균 뿐만 아니라 알파용혈 사슬균에 대해서도 비교분석을 하였고 그 결과 알파용혈 사슬균에 대해 높은 일치율이 관찰되어 임상미생물 검사실에서 신속 정확한 최소발율 억제농도를 측정하는데 많은 도움이 되리라 생각된다.

• Molecules and Cells
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• 제27권2호
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• pp.149-157
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• 2009

In both gram-positive and several gram-negative bacteria, the transcription of dnaK and groE operons is negatively regulated by HrcA; however, the mechanism modulating HrcA protein activity upon thermal stress remains elusive. Here, we demonstrate that HrcA is modulated via reduction and oligomerization in vitro. Native-PAGE analysis was used to reveal the oligomeric structure of HrcA. The oligomeric HrcA structure became monomeric following treatment with the reducing agent dithothreitol, and this process was reversed by treatment with hydrogen peroxide. Moreover, the mutant HrcA C118S exhibited reduced binding to CIRCE elements and became less oligomerized, suggesting that cysteine residue 118 is important for CIRCE element binding as well as oligomerization. Conversely, HrcA mutant C280S exhibited increased oligomerization. An HrcA double mutant (C118S, C280S) was monomeric and exhibited a level of oligomerization and CIRCE binding similar to wild type HrcA, suggesting that cysteine residues 118 and 280 may function as checks to one another during oligomer formation. Biochemical fractionation of E. coli cells overexpressing HrcA revealed the presence of HrcA in the membrane fraction. Together, these results suggest that the two HrcA cysteine residues at positions 118 and 280 function as reduction sensors in the membrane and mediate oligomerization upon stress.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.240-240
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• 1996

Staphylococcus aureus, Klebsiella pneumoniae, Enterobacter cloacae, Proteus mirabilis 및 Pseudomonas aeruginosa에 의한 mouse 복강내감염증에 대하여 DA-1131은 IPM/CS와 MEPM/CS에 비하여 현저히 우수한 치료효과를 나타내었다. 백혈구감소 mouse에서의 P. aeruginosa에 의한 복강내감염증에 대하여도 DA-1131은 IPM/CS와 MEPM 및 MEPM/CS보다 동등 이상의 우수한 치료효과를 나타내었다. K. pneumoniae를 감염균으로 한 mouse 호흡기감염 후 생존율 평가 시험에서 DA-1131 투여 mouse는 IPM/CS 및 MEPM/CS에 비하여 현저히 우수한 생존율을 나타내었고, 동시에 MEPM/CS와 유사한 폐내 생균수의 감소 pattern이 확인되었으며, IPM/CS에 비하여 균의 재증식을 억제하는 효과가 우수하였다. P. mirabilis에 의한 mouse 요로감염증에서는 DA-1131 투여군의 신장내 생균수감소는 MEPM/CS와 동등한 수준인 것으로 나타났으나 IPM/CS에 비하여는 매우 우수하였다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.239-239
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• 1996

DA-1131은 Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Proteus mirabilis, Proteus vulgaris 및 Pseudomonas aeruginosa 의 시험균주에 대하여 1-4의 MBC/MIC 비를 나타내었으며, 약물첨가에 의한 세균증식억제 과도 매우 우수하였으므로 광범위의 강력한 살균력을 나타내는 것으로 확인되었다. DA-1131의 PAE는 S. aureus Smith에 대하여는 1.28시간, K. pneumoniae 1에 대하여는 0.65시간, P. aeruginosa 93에 대하여는 1.90시간으로 나타나, MIC 이하의 낮은 농도에서도 세균에 대한 생육저해 효과가 관찰되었으며, 이러한 현상은 E. coli K-12에 DA-1131을 1/4 MIC(0.0125 $\mu\textrm{g}$/$m\ell$) 농도로 작용시켰을 때 균의 팽화와 신장 및 구형화가 동시에 일어나는 등 균형태변화를 초래하는 효과와 큰 상관성을 나타내었다. 또한, DA-1131은 감염방어효 에 매우 큰 영향을 끼치는 mouse macrophage와 매우 우수한 협력적살균작용을 나타내어 E. coli K-12 생세포는 1/16 MIC 이상의 DA-1131 공존하에서 쉽게 식균소화(phagocytosis) 되었다.

• Food Science and Biotechnology
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• 제14권2호
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• pp.196-199
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• 2005

Antimicrobial activity of persimmon leaf tea methanol extracts on Klebsiella pneumoniae and Staphylococcus aureus was examined through paper disk diffusion bioassay. K. pneumoniae and S. aureus showed 87.64 and 99.35% growth inhibitions by addition of steamed tea methanol extracts (10 mg/ml), respectively. The number of microorganisms in rice cakes was significantly reduced when leaf tea powder was added during production of rice cakes. Addition of 1% steamed leaf teas to rice cakes decreased the number of microorganisms by over 50%, and over 70% reduction was observed when final 2% (dried weight w/w) steamed leaf tea was added, whereas no significant effect was observed over 2%. These results indicate that different microorganisms were detected from persimmon leaf and rice cake, and persimmon leaf can inhibit normal microbial growth in rice cake.

• 미생물학회지
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• 제17권1호
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• pp.1-15
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• 1979

Mycoplasma pneumoniae strain CL-s attached to broth-covered surfaces was examined sequentially during growth from single cells for morphologic and ultrastructural changes using several different electron microscopic techniques. Changes in morphology revealed both round and spindle shapes and observation of cell transitions suggested some type of morphological cycle. The round to-ovoid cells observed in the early stages of growth appeared to be viable, and morphologically and ultrastructurally different from the spherical fors which were produced during the latter stage of growth. The spindle segments were detected appeared to be structurally the same as the terminal cored structure seen in thin sections and may be a growing point or an attachment site of the cell. A tubular structure was observed in the core of the terminal structure and a microtubule-like element appeared to bridge between some spindle segments. A matrix sunstance was observed around single cells as well in the intercellular space of the colonies prepared by critical point metrical triple-layered cytoplasmic mermbranes, surfaces, of which appeared to be structurally different each other, were observed in young cells, whereas symmetrical and thicker membranes were seen in older cells. Small bodies were found in 4d or older cultures and did not appear to contain any internal structures or an easily detectable unit membrane.

• BMB Reports
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• 제35권5호
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• pp.482-487
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• 2002

Early activation of human peripheral blood polymorphonuclear neutrophils is characterized by their morphological changes from spherical to polarized shapes. The endotoxins from enteric pathogens (S. dysenteriae type 1, V. cholerae Inaba 569B, S. typhimurium, and K. pneumoniae) were assessed by their ability to induce morphological polarization of the neutrophils as measures of early activation. Phagocytic activity, adhesion, chemokinetic locomotion, and nitroblue tetrazolium (NBT) dye-reduction ability measured the later activation of the cells. Neutrophils showed distinct morphological polarization in suspension over a wide range of concentrations of these endotoxins when were compared with those that were induced by the standard chemotactic factor, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP). It was discovered that all of the endotoxins induced locomotor responses in neutrophils in suspension that were dose- and time-dependent. The optimum concentration for the endotoxins of S. dysenteriae, V. cholerae, and K. pneumoniae was 1 mg/ml in which 71, 69, and 66% of the neutrophils were polarized. However, the S. typhimurium dose was 2 mg/ml in which 50% of the cells responded. Neutrophils that were stimulated with endotoxins also showed increased random locomotion (p<0.005) through cellulose nitrate filters, but an enhanced adhesion of the cells to glass surfaces (p<0.03). These are important functions of these cells to reach and phagocytose damaged cells, as well as invading microorganisms. Interestingly, the endotoxins had a highly-significant inhibitory effect upon the proportions of neutrophils phagocytosing opsonized yeast (p<0.01) with a small number of yeast that were engulfed by the cells (p<0.02). Further, endotoxin-treated cells showed an enhanced ability to reduce NBT dye (p<0.03). Therefore, we concluded that endotoxins of enteric pathogens are neutrophil chemotactic factors.

• 대한의생명과학회지
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• 제14권4호
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• pp.257-261
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• 2008

Cellular phones are the most used electronic device everyday in modern life and are always in contact with our hands, Although many studies have revealed microorganisms living on our hands, there are only a few reports on the research about products or places which are in contact with our hands. Therefore, the purpose of this study is to verify microorganisms living in cellular phones. Microorganisms were scraped from cellular phones of students and professors from the clinical laboratory science department in Daegu Health College, and cultured at Brain Heart Infusion agar and MacConkey agar following API kit to identify them. The average colony number was $1.5{\times}10^2$ on BHI agar and $40{\times}10$ on MacConkey agar. There was no difference according to gender. In Gram stain result, Gram(+) Cocci showed the highest frequency. Also in BHI agar plates, Micrococcus spp and Acinetobacter baumannii identified with high frequency. Moreover, S. aureus, which is very well known as strong food poisoning bacteria, was isolated. Klebsiella pneumonia ssp pneumonia was isolated with the highest frequency from the MacConkey agar or S-S agar plate. From these results show, there are as many different microorganisms from cellular phones as from our hands. This is the first report isolating strong food poisoning bacteria in cellular phones. Since infection in hospitals have been an important issue to be aware of, it is equally necessary to investigate cell phones and products which hospital workers touch with their hands.

• KSBB Journal
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• 제15권2호
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• pp.162-166
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• 2000

도라지에 H2O, ethanol, ethyl ether와 petroleum ether를 용매로 하여 추출한 시료를 기관지질환 유발세균(S. aureus, C. diphtheriae, Mycobacterium sp. F. nucleatum, A. funicatus, K. pneumoniae, S. pyogenes N. gonorrhoeae)에 투여한 결과 ethyl ether, petroleum ether, H2O와 ethanol의 순으로 항균력이 우수하다는 것이 판명되었다. 특히, ethyl ether에 의한 도라지 추출물의 항균력이 80%이상 뛰어난 효과를 나타내었다. 우수한 항균력을 가지는 도라지 추출물의 농도는 30mg부터 30%이상의 억제작용을 보였으며 70mg에서 70%이상의 세포 성장이 저해되는 현상을 관찰하였다. 기관지 질환 유발세균에 대한 도라지의 효과는 대조구에 비해 70%이상의 탁월한 항균효과가 있는 것으로 확인되었다.

• 대한미생물학회지
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• 제19권1호
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• pp.41-48
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• 1984

The present study was undertaken to elucidate the antibacterial spectrum of L. casei phage type $J_1$ strain isolated from a fermented milk product against pathogenic enteric bacteria. Growth inhibitory effects and minimum inhibitory concentration(MIC) of culture supernatants of L. casei grown in MRS broth were measured by both plate culture method and microplate broth dilution technique against Salmonella typhi, Salmonella typhimurium, Shigella flexneri, Shigella dysenteriae, enterpathogenic E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. The results are summarized as follows: 1. The MRS broth culture of L. casei gave a similar extent of growth inhibitory effects against S. typhi, S. typhimurium, S. flexneri, S. dysenteriae, E. coli, K. pneumoniae and P. aeruginosa, respectively. 2. The inhibitory effects of L. casei culture were observed either in whole broth culture or in culture supernatant, but neither the bacterial suspension nor the neutralized culture supernatant showed such as antibacterial activities. 3. The MIC titres of the culture supernatants were ${\log_2}5$ to ${\log_2}6$, whereas those of the neutralized culture supernatant dropped markdely to ${\log_2}2$ to ${\log_2}3$. These results indicated that major portion of growth inhibitory effects of MRS broth culture of L. casei against enteric bacterial pathogens was possibly due to the acids produced, and minor portion to other antibacterial substances.