반코마이신 내성 장구균에 대한 광에너지 요법의 효과

권필승 대한임상검사과학회 2011 대한임상검사과학회지(KJCLS) Vol.43 No.3

The aim of this study was to evaluate the effects of the photosensitizer photogem with light-emitting diode (LED) on vancomycin-resistant enterococci (VRE). Two VRE strains isolated from the feces of patients. that was identificated Enterococcus faecium (vanA) and Enterococcus gallinarum (vanC1) using traditional biochemical tests and confirmed VRE genotyping from using polymerase chain reaction. In addition, three strains were used Enterococcus. faecalis CDC-286 (vanA), E. faecalis CDC-583 (vanB) and E. gallinarum CDC-42 (vanC1). To examine the antimicrobial effect of photogem mediated photodynamic therapy (PDT) against, CFU quantification and Disk diffusion antimicrobial susceptibility test were evaluated. The effects of Photodynamic therapy was not associated with genotype. Photogem mediated PDT perfectly inhibited the colony formation of E. faecalis CDC-286. The number of viable bacteria decreased greatly after PDT application with photogem 50 µg/mL and energy density of 15 J/ ㎠. The diameter of inhibition zone was increased to after PDT more than before PDT. The case of vancomycin disc on E. faecalis CDC-583 and E. galinanum-Patient were changed from resistant to intermediate resistant, from intermediate resistant to susceptable. These results demonstrate that lethal photosensitization of VRE can be achieved using photogem plus 630 nm LED irradiation. .

병원성세균에 대한 5-Aminolevulinic Acid로 중재된 광역학치료의 항균효과

권필승 대한임상검사과학회 2022 대한임상검사과학회지(KJCLS) Vol.54 No.4

This study evaluates the improved effect of photodynamic therapy (PDT) by subjecting pathogenic bacteria to a combination of 630 nm light-emitting diode (LED) and 5-aminolevulinic acid (ALA). Bacterial suspensions of 1.5×104 cells/mL were diluted and exposed to ALA concentrations of 10, 5, 2.5, 1.25, and 0.625 mg/mL, incubated for 30 minutes, followed by irradiation with 630 nm LED (18 J/cm2). The non-irradiated P. aeruginosa group and the group administered only LED light averaged 415 and 245 colonies, respectively. Conversely, the PDT group showed an average of 109, 225, 297, and 285 colonies at concentrations of 10, 5, 2.5, and 1.25 mg/mL of ALA. Evaluating the effect on E. faecalis revealed an average of 8,750 and 8,000 colonies in the group that did not receive the control photosensitizer and the group exposed to light alone, respectively. However, an average of 0, 2350, 4825, and 7475 colonies at concentrations of 5, 2.5, 1.25, and 0.625 mg/mL ALA were determined for the PDT groups. In conclusion, better inhibitory effects were observed for E. faecalis than for P. aeruginosa. Moreover, our results validate the possibility of improved PDT efficacy using a combination of ALA and 630 nm LED.

형광화학센서를 이용한 살아있는 세포 내에서의 중금속이온검출

권필승,김진경,김종완,Kwon, Pil-Seung,Kim, Jin-Kyung,Kim, Jong-Wan 대한화학회 2010 대한화학회지 Vol.54 No.4

세포내의 중금속이온의 형광검출은 유기분자화학과 세포생물학분야에서 높은 관심을 갖는다. 이 연구는 형광화학센서(FS)를 이용한 Hg$^{2+}$ 과 Zn$^{2+}$의 세포 내 검출을 목적으로 하였다. FS는 약한 형광을 나타내지만 Zn$^{2+}$와 결합 시에는 강한 방출 형광은 낸다. 2FS/Zn$^{2+}$의 형광증가는 FS-Hg$^{2+}$결합의 형성할 때 Hg$^{2+}$ 1당량만 추가에도 완전한 형광감소를 나타낼 수 있었다. 네가지의 세포주(LLC-MK2, Hela, HT29 and AMC-HN3)는 공촛점 현미경에 대한 형광이미지를 위하여 사용하였다. 세포생존능은 LLC-MK2 세포주에 FS, Zn$^{2+}$, FS-Zn$^{2+}$, Hg$^{2+}$의 처리 후에 평가하였다. FS의 세포독성능은 80%이상의 생존능을 보였다. 본 연구에서는 FS가 살아있는 세포내의 Hg$^{2+}$과 Zn$^{2+}$의 선택적 이미지를 검출할 수 있음을 보여주었다. The fluorescence detection of intracellular metal ions are high interest in the fields of organic molecular chemistry and cellular biology. This study was purposed to detection for mercury and zinc in the cell using fluorescent chemosensor (FS). FS exhibits a weak fluorescence, but emits strong fluorescence upon Zn$^{2+}$ complexation. The increased fluorescence of the 2FS/Zn$^{2+}$ can be quenched completely by addition of only 1 equiv of Hg$^{2+}$ with the formation of complex FS-Hg$^{2+}$. Four cell lines (LLC-MK2, Hela, HT29 and AMC-HN3) were used for fluorescence imaging by confocal microscope. The cell viability MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was evaluated after cell treatment of FS, Zn$^{2+}$, FS-Zn$^{2+}$, Hg$^{2+}$ on LLC-MK2 cell line. The cytotoxicity of FS was showed to viability over 80%. This study has shown that FS can be detected for selective imaging of Zn$^{2+}$ and Hg$^{2+}$ in living cells.

P-10 : In vitro activities of retapamulin and fusidic acid against Mupirocin-Resistant, Methicillin-Resistant Staphylococcus aureus from Clinical Samples

권필승,박석돈,김신무 대한임상병리사협회 2013 임상미생물검사학회 발표자료집 Vol.2013 No.-

Background: In vitro activities of retapamulin against mupirocin resistant, methicillin-resistant Staphylococcus aureus isolates in Korea is not well known. The aims of the study were to determine the activity of retapamulin and fusidic acid against mupirocin resistant, MRSA isolates from clinical specimens. Method: MRSA isolates were collected from three university hospitals in 2009-2010. Antimicrobial susceptibility was tested by the CLSI the agar dilution methods. femA, mecA and mupA genes were detected by PCR. Results: Overall 6.9% of 175 MRSA isolates were resistant to mupirocin, with prevalence ranging from 0% to 10% depending on hospitals. Two of nine, and one of three M-R isolates from hospital A, and hospital B, respectively, showed high-level mupirocin resistance. Antimicrobials with low MIC90 for both low-level (LL) and HL M-R isolates were vancomycin (1 ㎍/ml) and rifampin (0.5 ㎍/ml). All M-R isolates were resistant to ciprofloxacin, clindamycin, and erythromycin. Eight of nine, and one of three LL and HL M-R isolates were resistant to fusidic acid, respectively. PFGE analysis showed three HL M-R isolates belonged to three clusters with ~<90% similarity compared to LL M-R isolates. Discussion: Mupirocin resistance rate of MRSA varied from 0% to 10% depending on hospitals. HL mupirocin resistance was detected in two hospitals. All M-R isolates were susceptible to rifampin and vancomycin. Analysis of PFGE pattern suggested that majority of HL-resistant isolates were clonally not related.

블렌딩 에센션오일의 항균효과 증진

권필승,김대중,박호,Kwon, Pil Seung,Kim, Dae-Jung,Park, Ho 대한임상검사과학회 2017 대한임상검사과학회지(KJCLS) Vol.49 No.3

Essential oil from herb is known to exert pharmacological effects on the human body. In this study we investigated the antibacterial activity of 4 essential oils (teetree, rosemary, melisa, and lavender), as well as the blended mixture oil of teetree, rosemary, and melisa (TRM) on three bacteria, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Antibacterial analysis was performed using the standard disk diffusion method, and minimum inhibition concentration was determined by the broth microdilution method with different concentrations of essential oils (0.5, 1, 2 and 3 mg/mL). After incubation at $37^{\circ}C$ for 24 h, the antibacterial activity was assessed by measuring the zone of growth inhibition surrounding the disks. Herb oil with the inhibition zones showed varied values ranging from6 to 25 mm. However, the components of herb oil of TRM are as highly active as the teetree oil against pathogens, generating large inhibition zones for both gram negative and positive bacteria (13~22 mm and 8 mm inhibition zones). In the analysis for MIC, TRM showed growth-inhibitory effects at 0.0625% for S. aureus and E. coli, and 1.25% for P. aeruginosa. This result demonstrated that the anti-microbial activity of TRM was greater than a single herb oil, including oxacillin, rosemary, and teetrea. As a single herb oil, both rosemary and teetrea also had an anti-microbial effect by itself, and we can expect that the blended oil mixture may exert a synergistic effect against multidrug resistant bacteria, suggesting its future application in natural preservative agents for health food and cosmetics.

여드름균에 대한 청색 발광다이오드와 포토프린과 라다클로린을 이용한 광역학치료의 항균효과

권필승 대한임상검사과학회 2015 대한임상검사과학회지(KJCLS) Vol.47 No.1

Photodynamic therapy (PDT) apply photosensitizers and light. The purpose of this study was to evaluate the in vitro efficacy of PDT using blue LED (light emitting diode) with photofrin and radachlorin for Propionibacterium acnes. The colony forming units method was used to assess the antibacterial activity. Suspension (1 mL) containing P. acnes at 1×105 CFU/mL were prepared and then 2 fold serial diluted to 12.5 g/mL from 50 g/mL concentration of photofrin and radachlorin. After 60 minutes incubation, light was irradiated for 10 to 30 minutes using the following light source of wavelength 460 nm, each energy density 36, 72 and 108 J/cm2. Bacterial growth was evaluated after 72 hours incubation in a Phenylethanol Blood Agar (PEBA) culture. In addition, flow cytometric analysis were performed to measure the live cell after PDT. Also transmission electron microscopy (TEM) was employed to evaluate the effect of pathogens by PDT. The PDT Group was perfectly killed to all kind of photosensitizers dose of 12.5 g/mL with irradiation of 10 minutes. Also other Groups were killed to all kind of photosensitizers dose of 6.25 g/mL with irradiation time of 20 and 30 minutes. The flow cytometry showed a lower number of viable bacteria in the PDT group compared to the control group. The images of the TEM results were showed in cytoplasmic membrane damage and partially deformed to cell morphologies. These results suggest that radachlorin and photofrin combine blue LED PDT can be effectively treated when was proved treatment for acnes therapy.

포토프린을 이용한 황색포도알균과 표피포도알균에 대한 광역학 치료의 항균효과

권필승(Pil-Seung Kwon) 한국콘텐츠학회 2013 한국콘텐츠학회논문지 Vol.13 No.2

광역학 치료는 미생물의 감염을 포함한 다양한 질병을 위한 대안치료로 권장된다. 이 연구의 목적은 포도알균속에 대한 직접제작한 630 nm 발광다이오드와 포토프린을 사용하여 광역학 치료의 항균효과를 평가하고자 하였다. 포토프린을 이용한 광역학 치료는 황색포도알균과 표피포도알균에 대한 항균효과를 집락형성수 정량법과 세균 생육능은 유세포분석기를 이용하여 시험하였다. 황색포도알균과 표피포도알균의 집락형성수 결과는 포토프린 50 ㎍/㎖와 630 nm 발광다이오드로 에너지밀도 18 J/㎠ 조건으로 광역학 치료 적용 후 각각 평균 1 cfu/ml와 평균16 cfu/ml이다. 추가로 광역학 치료 후 황색포도알균과 표피포도알균을 유세포분석기로 세포의 크기와 형광강도를 측정하였다. 황색포도알균과 표피포도알균의 세포크기는 광역학 치료 후 평균 8.96% 5.55%씩 각각 증가하였고, 세균의 죽은세포는 각각 39%와 61%로 증가하였다. 이 결과로 포토프린을 이용한 광역학 치료는 항균치료의 방법으로 효과적인 방법이 될 수 있음을 제의한다. Photodynamic therapy(PDT) has been recommended as an alternative therapy for various diseases including microbial infection. The aim of the present study is to evaluate the antimicrobial effect of PDT using a photofrin and home made 630 nm Light emitting diode(LED) against Staphylococci. To examine the antimicrobial effect of photofrin-mediated PDT against Staphylococcus aureus and Staphylococcus epidermidis colony forming units(CFU) quantification, and bacterial viability using flow cytometry were formed. The CFU quantification results of S. aureus and S. epidermidis were 1 cfu/ml and 16 cfu/ml of average, respectively, after PDT application with photofrin of 50 ㎍/㎖ and 630 nm LED and energy density of 18 J/㎠. In addition, S. aureus and S. epidermidis isolates yielded forward-scatter (FSC) and fluorescence intensity (FI) differences on flow cytometry (FCM) after PDT. S. aureus and S. epidermidis cell size(FSC) increased 8.96% and 5.55% respectively, after PDT. Also the numbers of dead cell of S. aureus and S. epidermidis were a 39% and 61% incerased. These results suggest that photofrinmediated PDT can be an effective alternative treatment for antibacterial therapy.

금식 여부에 따른 혈당치 분포와 당뇨병 선별을 위한 혈당조절지표의 평가

권필승 ( Pil Seung Kwon ),임인수 ( Insoo Rheem ) 대한임상검사과학회 2016 대한임상검사과학회지(KJCLS) Vol.48 No.4

This study analyzed the distribution of the blood glucose level according to the fasting status. Moreover, a relationship was analyzed between fasting blood glucose level and glycemic control indicators. A total of 707 outpatients, who visited Dankook University Hospital, were included and classified into either the fasting group and the non-fasting group. The mean blood glucose level of each group was calculated and analyzed by sex, age, and clinic. In addition, blood glucose, HbA1c, fructosamine, and 1,5-AG were measured in 153 fasting health check-up patients, and the correlation between the blood glucose level and glycemic control indicators was evaluated. Blood glucose averages between the two groups (non-fasting 111.9 vs. fasting 103.6 mg/dL) were different (p<0.05); and the mean difference was lower in women (4.8 mg/dL) than in men (12.2 mg/dL). A significant difference of the median glucose values among the age groups was only observed in the non-fasting group (Kruskal-Wallis test, p<0.01), and not in the fasting group. A 1,5-Anhydroglucitol was estimated to be significantly correlated with the fast blood glucose level in the range of the criteria of impaired fasting glucose (IFG). We presented an assessment of the distribution of blood glucose level in accordance with the fasting status among outpatients, and estimated that 1,5-anhydroglucitol was well correlated with the fasting blood glucose than fructosamine and HbA1c, through the analysis of results of health screening subjects. It is suggested that the use of glycemic indicators that reflect short-term blood glucose control can be used together with the blood glucose measurement in the screening of diabetes mellitus.

장내세균 5종의 Endotoxin 정량 비교

권필승 ( Pil Seung Kwon ) 대한임상검사과학회 2016 대한임상검사과학회지(KJCLS) Vol.48 No.2

세균내독소는 lipopolysaccharide (LPS)라고 불리우며, 그람음성 세균의 세포벽에 존재하는 물질로 어느 생체재료나 액체에 존재할 수 있다. 세균내독소가 혈액으로 침투되면 발열 및 염증을 유발시킨다. 본 연구에서는 장내 그람음성세균인 Escherichia coli O157:H7, Klebsiella oxytoca, Salmonella Typhi, Shigella sonnei, Morganella morganii의 LPS 양을 비교하려 하였다. 각 세균은 배양한 후 1.5×108 CFU/mL 농도로 희석하여 동일한 농도로 하였으며 실험의 정당성을 위하여 LAL시약의 표시감도확인시험을 진행하였다. 10 fold dilution 후 1차 시험을 하여 각 균의 반응end point를 확인하고 바로 윗단계 희석배수 사이에서 2 fold dilution하여 균의 최종 반응 end point를 확인하였다. 결과적으로 E. coli O157은 75∼37.5 CFU/mL, K. oxytoca는 37.5∼18.75 CFU/mL, M. morganii와 S. Typhi는 3.75∼1.875 CFU/mL, S. sonnei는 7.5∼3.75 CFU/mL에서 0.015 EU/mL 이상의 endotoxin이 검출되었다. 최종적으로 억제인자에 대한 확인시험을 진행하여 결과값을 보증하였다. 본 연구를 통하여 세균내독소에 대한 추가적인 연구가 지속되기를 기원한다. Endotoxin, also known as lipopolysaccharide (LPS) produced by the cell wall of gram negative bacteria can be present in any liquid or on any biomaterial. Endotoxin in blood can cause fever and inflammation. In this study, we compared bacterial endotoxin using Escherichia coli O157:H7, Klebsiella oxytoca, Salmonella Typhi, Shigella sonnei and Morganella morganii. Bacteria were cultured for use in the experiment, and diluted to 1.5×108 CFU/mL. A check marked sensitivity confirmatory test of the Limulus amebocyte lysate (LAL) reagent was performed to examine the validity. The end point reaction to each bacteria sample was confirmed with 10 fold dilution and then the final reaction end point was confirmed by 2 fold dilution between the dilution step and the upper dilution step. According to the results, in detection of endotoxins in more than 0.015 EU/mL, E. coli O157 was 75∼37.5 CFU/mL, K. oxytoca 37.5∼18.75 CFU/mL, M. morganii and S. Typhi 3.75∼1.875 CFU/mL, and S. sonnei 7.5∼3.75 CFU/mL. The resulting value was finally ensured by a confirmation test for the inhibitory factor. Based on this study, conduct of further research on bacterial endotoxin is encouraged.

라다클로린으로 매개된 광역학치료에 의한 백색 캔디다 바이오필름의 비활성

권필승 ( Pil Seung Kwon ) 대한임상검사과학회 2015 대한임상검사과학회지(KJCLS) Vol.47 No.4

The purpose of this study was to evaluate the in-vitro efficacy of PDT using red light emitting diode (LED) with Radachlorin for biofilm inhibition of clinical Candida albicans isolates. The suspensions containing C. albicans at 9×10(8)CFU/mL were prepared on yeast nitrogen base containing 5% glucose. The biofilm formation was grown for 3 h after seeding suspensions each 100 ul on a 96-well plate and then supernatant was discarded. Each well was treated with 0.39 μg/mL from 50 μg/mL concentrations of Radachlorin on adherent biofilm. After a 30-minute incubation, light was irradiated for 30, 60, or 90 minutes using the following light source of wavelength 630 nm LED, at energy densities of 14, 29, and 43 J/cm2. Afterwards, all supernatant was removed and dried. Adherent cells were stained with safranin O and dried. The cell viability was measured using a microplate reader at 490 nm. Also, a fluorescent signal on C. albicans was observed by saturation of a photosensitizer. In conclusion, a significant inhibition of 72.5% was observed to C. albicans on biofilm at the Radachlorin dose of 50 μg/mL with 630 nm LED. The Photosensitizer (Radachlorin) was adequate at 30 minuttes for C. albicans. Overall, the results showed that inhibition of biofilm formation was Radachlorine dose-dependent. The results suggest that PDT, using Radachlorin with 630 nm LED, is able to decrease biofilm formation of C. albicans.