성장배지 혈액 유무가 구강미생물의 적색 형광 발현에 미치는 영향

정승화 ( Seung-hwa Jeong ),양용훈 ( Yong-hoon Yang ),이민아 ( Min-ah Lee ),김세연 ( Se-yeon Kim ),김지수 ( Ji-soo Kim ) 대한예방치과·구강보건학회 2017 大韓口腔保健學會誌 Vol.41 No.4

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℃ for 7 days. Tryptic soy agar with hemin and vitamin K₃ (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.

Porphyromonas gingivalis가 일부 구강미생물의 형광 발현에 미치는 영향

김세연 ( Se-yeon Kim ),우동협 ( Dong-hyeob Woo ),이민아 ( Min-ah Lee ),김지수 ( Ji-soo Kim ),이정하 ( Jung-ha Lee ),정승화 ( Seung-hwa Jeong ) 대한예방치과·구강보건학회 2017 大韓口腔保健學會誌 Vol.41 No.1

Objectives: Dental plaque is composed of 700 bacterial species. It is known that some oral microorganisms produce porphyrin, and thus, they emit red fluorescence when illuminated with blue light at a specific wavelength of <410 nm. Porphyromonas gingivalis belongs to the genus Porphyromonas , which is characterized by the production of porphyrin. The aim of this study was to evaluate red fluorescence emission of some oral microorganisms interacting with P. gingivalis. Methods: Five bacterial strains (P. gingivalis, Streptococcus mutans, Lactobacillus casei, Actinomyces naeslundii, and Fusobacterium nucleatum) were used for this study. Tryptic soy agar medium supplemented with hemin, vitamin K3, and sheep blood was used as a growth medium. The fluorescence emission of bacterial colonies was evaluated under 405 nm-wavelength blue light using a Quantitative Light-induced Fluorescence Digital (QLF-D) camera system. Each bacterium was cultured alone and cocultured in close proximity with P. gingivalis. The red/green (R/G) ratio of fluorescence image was calculated and the differences of R/G ratio according to each growth condition were compared using the Mann-Whitney test (P<0.05). Results: Single cultured S. mutans , L. casei and A. naeslundii colonies emitted red fluorescence (R/ G ratio=2.15±0.06, 4.31±0.17, 5.52±1.29, respectively). Fusobacterium nucleatum colonies emitted green fluorescence (R/G ratio=1.36±0.06). The R/G ratios of A. naeslundii and F. nucleatum were increased when P. gingivalis was co-cultured with each bacterium (P<0.05). In contrast, the R/G ratios of S. mutans and L. casei were decreased when P. gingivalis was co-cultured with each bacterium (P=0.002, 0.003). Conclusions: This study confirmed that P. gingivalis could affect the red fluorescence of other oral bacteria under 405 nm-wavelength blue light. Our findings concluded that P. gingivalis has an important role for red fluorescence emission of dental biofilm.

Fluorescence change of Fusobacterium nucleatum due to Porphyromonas gingivalis

이민아,강시묵,김세연,김지수,김진범,정승화 한국미생물학회 2018 The journal of microbiology Vol.56 No.9

The aim of this study was to measure changes in the fluorescence of Fusobacterium nucleatum interacting with Porphyromonas gingivalis for excitation with blue light at 405-nm. P. gingivalis was mono- and co-cultivated in close proximity with F. nucleatum. The fluorescence of the bacterial colonies was photographed using a QLF-D (Quantitative Light-induced Fluorescence-Digital) Biluminator camera system with a 405 nm light source and a specific filter. The red, green and blue intensities of fluorescence images were analyzed using the image analysis software. A fluorescence spectrometer was used to detect porphyrin synthesized by each bacterium. F. nucleatum, which emitted green fluorescence in single cultures, showed intense red fluorescence when it was grown in close proximity with P. gingivalis. F. nucleatum co-cultivated with P. gingivalis showed the same pattern of fluorescence peaks as for protoporphyrin IX in the red part of the spectrum. We conclude that the green fluorescence of F. nucleatum can change to red fluorescence in the presence of adjacent co-cultured with P. gingivalis, indicating that the fluorescence character of each bacterium might depend on the presence of other bacteria.

Comparison of Clinical Characteristics of Fluorescence in Quantitative Light-Induced Fluorescence Images according to the Maturation Level of Dental Plaque

( Eun-ha Jung ),( Hye-young Oh ) 한국치위생과학회 2021 치위생과학회지 Vol.21 No.4

Background: Proper detection and management of dental plaque are essential for individual oral health. We aimed to evaluate the maturation level of dental plaque using a two-tone disclosing agent and to compare it with the fluorescence of dental plaque on the quantitative light-induced fluorescence (QLF) image to obtain primary data for the development of a new dental plaque scoring system. Methods: Twenty-eight subjects who consented to participate after understanding the purpose of the study were screened. The images of the anterior teeth were obtained using the QLF device. Subsequently, dental plaque was stained with a two-tone disclosing solution and a photograph was obtained with a digital single-lens reflex (DSLR) camera. The staining scores were assigned as follows: 0 for no staining, 1 for pink staining, and 2 for blue staining. The marked points on the DSLR images were selected for RGB color analysis. The relationship between dental plaque maturation and the red/green (R/G) ratio was evaluated using Spearman’s rank correlation. Additionally, different red fluorescence values according to dental plaque accumulation were assessed using one-way analysis of variance followed by Scheffe’s post-hoc test to identify statistically significant differences between the groups. Results: A comparison of the intensity of red fluorescence according to the maturation of the two-tone stained dental plaque confirmed that R/G ratio was higher in the QLF images with dental plaque maturation (p<0.001). Correlation analysis between the stained dental plaque and the red fluorescence intensity in the QLF image confirmed an excellent positive correlation (p<0.001). Conclusion: A new plaque scoring system can be developed based on the results of the present study. In addition, these study results may also help in dental plaque management in the clinical setting.

Red Fluorescent Donor-π-Acceptor Type Materials based on Chromene Moiety for Organic Light-Emitting Diodes

윤진영,Jeong Seob Lee,윤승수,김영관 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.6

Two red emitters, 2-(7-(4-(diphenylamino)styryl)-2-methyl-4H-chromen-4-ylidene)malonitrile (Red 1) and 2- (7-(julolidylvinyl)-2-methyl-4H-chromen-4-ylidene)malonitrile (Red 2) have been designed and synthesized for application as red-light emitters in organic light emitting diodes (OLEDs). In these red emitters, the julolidine and triphenyl moieties were introduced to the emitting core as electron donors, and the chromederived electron accepting groups such as 2-methyl-(4H-chromen-4-ylidene)malononitrile were connected to electron donating moieties by vinyl groups. To explore the electroluminescence properties of these materials, multilayered OLEDs using red materials (Red 1 and Red 2) as dopants in Alq3 host were fabricated. In particular, a device using Red 1 as the dopant material showed maximum luminous efficiencies and power efficiencies of 0.82 cd/A and 0.33 lm/W at 20 mA/cm2. Also, a device using Red 2 as a dopant material presented the CIEx,y coordinates of (0.67, 0.32) at 7.0 V.

Red Fluorescent Donor-π-Acceptor Type Materials based on Chromene Moiety for Organic Light-Emitting Diodes

Yoon, Jhin-Yeong,Lee, Jeong Seob,Yoon, Seung Soo,Kim, Young Kwan Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.6

Two red emitters, 2-(7-(4-(diphenylamino)styryl)-2-methyl-4H-chromen-4-ylidene)malonitrile (Red 1) and 2-(7-(julolidylvinyl)-2-methyl-4H-chromen-4-ylidene)malonitrile (Red 2) have been designed and synthesized for application as red-light emitters in organic light emitting diodes (OLEDs). In these red emitters, the julolidine and triphenyl moieties were introduced to the emitting core as electron donors, and the chrome-derived electron accepting groups such as 2-methyl-(4H-chromen-4-ylidene)malononitrile were connected to electron donating moieties by vinyl groups. To explore the electroluminescence properties of these materials, multilayered OLEDs using red materials (Red 1 and Red 2) as dopants in $Alq_3$ host were fabricated. In particular, a device using Red 1 as the dopant material showed maximum luminous efficiencies and power efficiencies of 0.82 cd/A and 0.33 lm/W at $20mA/cm^2$. Also, a device using Red 2 as a dopant material presented the CIEx,y coordinates of (0.67, 0.32) at 7.0 V.

Mitochondria-targetable red-emitting probe for real-time fluorescence monitoring of NAD(P)H in live cells

Joo, Jin Hui,Youn, Dayoung,Park, Sun Young,Shin, Dong-Sik,Lee, Min Hee Elsevier 2019 Dyes and pigments Vol.170 No.-

<P><B>Abstract</B></P> <P>We have developed a mitochondria-targetable and red-emitting probe (<B>1</B>) that allows for the quantitative analysis of mitochondrial NAD(P)H in live human cells. Probe <B>1</B> is non-fluorescent and gets reduced in the presence of NAD(P)H to emit a strong fluorescence. This probe is highly selective to NAD(P)H over various potential biological interferants such as redox species, metals, anions, and other biomolecules. In addition, confocal microscopic images revealed the predominant accumulation of probe <B>1</B> into the mitochondria of human breast cancer cells (MDA-MB-231), as evident from the red fluorescence in response to NAD(P)H activity in glucose-treated cells as NAD(P)H induction model <I>vs.</I> cyanide 4-(trifluoromethoxy)phenylhydrazone-treated cells as NAD(P)H depletion model. Probe <B>1</B> can be used to differentiate between cancer (MDA-MB-231) and normal cells (NIH-3T3) based on mapping mitochondrial NAD(P)H-dependent fluorescence intensity. Probe <B>1</B> will be useful for various applications, ranging from elucidation of biological pathways to pathological diagnosis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A mitochondria-targetable and red-emitting dicyanoisophorone was developed for imaging mitochondrial NAD(P)H. </LI> <LI> This probe is non-fluorescent and gets reduced in the presence of NAD(P)H to emit a strong fluorescence at 615 nm. </LI> <LI> The detection limit was estimated to be 1.2 μM of NADH. </LI> <LI> This probe accumulated into the mitochondria of cancer cells and displayed red fluorescence to NAD(P)H activity. </LI> <LI> The probe differentiated cancer and normal cells based on mapping mitochondrial NAD(P)H-dependent fluorescence intensity. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Clinical assessment of oral malodor using autofluorescence of tongue coating

Lee, Eun-Song,Yim, Hyun-Kyung,Lee, Hyung-Suk,Choi, Jong-Hoon,Lee, Ji Hyun,Kim, Baek-Il Elsevier 2016 PHOTODIAGNOSIS AND PHOTODYNAMIC THERAPY Vol.13 No.-

<P><B>Abstract</B></P> <P><B>Objectives</B></P> <P>The aim of this study was to evaluate whether a new method using quantitative light-induced fluorescence-digital (QLF-D) was appropriate for the diagnosis of oral malodor by quantifying the fluorescence of tongue coating.</P> <P><B>Methods</B></P> <P>This study examined 103 healthy subjects who have an oral malodor as a main complaint. The levels of oral malodor were measured by organoleptic scores (OLS) and volatile sulfur compound (VSC) levels. The fluorescent tongue coating images captured by QLF-D were quantified as the integrated fluorescence score (IF score) by multiplying the intensity and area of fluorescence. The correlations between the fluorescence parameters and OLS as well as VSC levels and the diagnostic accuracy of the IF score were evaluated.</P> <P><B>Results</B></P> <P>The IF score of tongue coating showed a significant positive correlation with the OLS (<I>r</I> =0.54, <I>p</I> <0.01) and the VSC levels (<I>r</I> =0.49, <I>p</I> <0.01). This score was significantly differed with the level of oral malodor (<I>p</I> <0.001), and its AUC was 0.72 in identifying the patient with definite oral malodor (≥OLS 2).</P> <P><B>Conclusions</B></P> <P>A new method quantifying tongue coating fluorescence detected by QLF-D can be used to diagnose oral malodor and assess its severity in the clinical practice.</P> <P><B>Highlights</B></P> <P> <UL> <LI> QLF-D can visualize and detect tongue coating as red fluorescence. </LI> <LI> Tongue fluorescence detected by QLF-D is correlated to the severity of oral malodor. </LI> <LI> IF score can be used to evaluate oral malodor by quantifying tongue coating fluorescence. </LI> </UL> </P>

Single Amino Acid Replacement Transforms mCherry to a Far-red Fluorescent Protein

김예지,송경주,이화진,김도현,김진태,정민섭 한국생물공학회 2016 Biotechnology and Bioprocess Engineering Vol.21 No.6

Far-red fluorescent proteins are beneficial for imaging in mammals. Here, starting from mCherry, the most commonly used among the different types of red fluorescent proteins (RFP), not having a H-bond network in its original form, we sought to recover the hydrogen bond network in mCherry. By comparing the structure of wtGFP and mCherry, we focused on a few key residues involved in a proton wire, and discovered an I197T mutant that showed a more red-shifted fluorescence. The detailed optical and photo-switching properties of related engineered RFPs are described. This study will guide further development of monomeric far-red FPs.

Methyl Red: A Fluorescent Sensor for Hg2+ over Na+, K+, Ca2+, Mg2+, Zn2+, and Cd2+

Diganta Kumar Das,Priyanka Goswami,Champa Barman,Biva Das 대한환경공학회 2012 Environmental Engineering Research Vol.17 No.-

Methyl red (MR), a very well known acid base indicator (pKa = 5.2), shows fluorescence emission in the range 320 nm to 480 nm, with an emission maximum at 375 nm on excitation by photons at 310 nm. A fluorescent intensity titration of MR by Hg2+ ion, a well known toxic heavy metal ion, shows quenching of the fluorescent intensity of MR. The quenching continues till the concentration ratio between MR and Hg2+ ion becomes 1:1. Similar titration with a number of other metal ions, namely Na+, K+, Ca2+, Mg2+, Zn2+, and Cd2+, has very small effect on the fluorescent intensity of MR. Thus MR acts as a selective fluorescent sensor for Hg2+ ion by selective fluorescence quenching. The efficiency of fluorescence quenching value is found to be 8.0. The binding ratio and binding constant (β) between MR and Hg2+ ion are calculated from the fluorescence and UV/visible spectral data, and are found to be 1:1 and log β =4.68. The Hg:MR complex was found to be stable in the pH range 5.5 to 8.2.