• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.1101-1103
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• 2005

최근 레이저 진단 및 치료의 동향, 즉 조직선택성을 갖는 레이저 치료와 새로운 광-조직 작용을 갖는 레이저 진단에 관하여 조사 발표하고, PDT 및 PDD의 새로운 연구발전 방향을 제시한다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.3
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• pp.234-238
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• 2002

Photodynamic therapy (PDT) is based on a photochemical reaction which is initiated by light activation of a photosensitizer. The photosensitizer accumulates more in tumor tissues than in normal tissues and is activated with specific wavelength of light, usually laser. The photochemical reaction produces highly reactive oxygen products causing cytotoxiciy and vascular shutdown to the tumor. The advantages of PDT are its relative selective tumor destruction and tissue healing by regeneration, which can maintain important structures with very good functional and esthetic results. Therefore, PDT is considered as an alternative modality for cancers of the head and neck. In this article, we will report three cases of photodynamic therapy for treatment of oral leukoplakia, squamous cell carcinoma, and basal cell carcinoma of head and neck. It was observed that premalignant and malignant lesions responded well to the photodynamic therapy with Aminolevulinic acid (ALA) and $Foscan^{(R)}$. Photodynamic therapy can be considered as a new treatment method for the premalignant and malignant tumors in Oral and Maxillofacial Surgery.

• Korean Journal of Bronchoesophagology
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• v.15 no.1
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• pp.60-63
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• 2009

The photodynamic therapy (PDT) is a new treatment modality of destroying malignant tumors and pre-malignant lesions based on the use of photodynamical damage to tumor cells under the photochemical reactions. But the clinical reports of photodynamic application on the benign tumor of the internal organs were extremely rare. So we decribed our experience of one case of benign tracheal tumor successfully treated by PDT.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.1
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• pp.6-10
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• 2015

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 $1{\times}10^5CFU/mL$ were prepared and then 2 fold serial diluted to $12.5{\mu}g/mL$ from $50{\mu}g/mL$ 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 $108J/cm^2$. 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 $12.5{\mu}g/mL$ with irradiation of 10 minutes. Also other Groups were killed to all kind of photosensitizers dose of $6.25{\mu}g/mL$ 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.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.2
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• pp.149-157
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• 2022

The aim of this study was to evaluate the effects of erythrosine-mediated photodynamic therapy (PDT) on Streptococcus mutans biofilm recovery by counting its colony-forming units (CFUs) and via confocal laser scanning microscopy analysis at different time points following PDT. In PDT, photosensitizer was an erythrosine. S. mutans ATCC25175 biofilms were irradiated using an LED curing light. Chlorhexidine (CHX) was used as positive control. After each antimicrobial treatment, samples were cultured to allow biofilm recovery. Viability was measured by calculating the CFU counts after treatment and after every 3 hours for up to 24 hours. Immediately after treatment, the PDT and CHX groups showed equally significant decreases in S. mutans CFU counts compared to the negative control. After 12 hours of reculture, the PDT group showed no significant difference in the decrease in CFU count compared to the negative control, whereas the CHX group showed significantly lower CFU counts throughout the 24-hour period. Erythrosine-mediated PDT can effectively inhibit S. mutans biofilm formation. However, biofilm recovery occurred earlier in the CHX group after PDT. This study provides insights into the clinical effectiveness of PDT in preventing dental caries.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.9 no.1
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• pp.35-41
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• 2023

Photodynamic therapy (PDT), in which a photosensitizer (PS), light, and molecular oxygen are essential components, is a non-invasive and highly effective cancer therapeutic method. However, PDT suffers from the penetration limit of light caused by attenuation and scattering of light through tissues constraining its use to skin and endoscopically accessible cancers. Cerenkov luminescence (CL) is defined as the light illuminated when charged particles move in a dielectric medium at a velocity greater than the phase velocity of light. It is known that medical radioisotopes in preclinical and clinical settings have enough energy to generate CL, and lately, CL has been exploited as an excitation source for PDT without external light illumination. This review introduces state of the art studies of radioisotope-based PDT for cancer, in which radioisotopes are utilized as a light source.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3023-3028
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• 2013

Objective: Photodynamic therapy (PDT ) is a promising modality for the treatment of various tumors. In order to assist in optimizing treatment, we applied 5-ALA/PDT in combination with low-dose cisplatin to evaluate cytotoxicity in Hela cells. Methods: Antiproliferative effects of 5-ALA/PDT and cisplatin, alone and in combination, were assessed using MTT assay. To examine levels of apoptosis, Hela cells treated with 5-ALA/PDT, and combination treatment were assessed with Annexin-V/PI by flow cytometry. To investigate the molecular mechanisms underlying alterations in cell proliferation and apoptosis, Western blot analysis was conducted to determine the expression of p53, p21, Bax and Bcl-2 proteins. Results: MTT assays indicated that combination treatment obviously decreased the viability of Hela cells compared to individual drug treatment. In addition, it was confirmed that exposure of Hela cells to 5-ALA/PDT in combination with low-dose cisplatin resulted in more apoptosis in vitro. Synergistic anticancer activity was related to upregulation p53 expression and alteration in expression of p21, Bcl-2 and Bax. Conclusion: Our findings suggest that administration of 5-ALA/PDT in combination with the low-dose cisplatin may be an effective and feasible therapy for cervical cancer.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.1
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• pp.19-24
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• 2007

The aim of this study was to evaluate the bacterial effects of Moraxella catarrhalis in otitis media with effusion (OME) by photodynamic therapy (PDT). Bacterial suspensions (10000 CFU/mL) were prepared. The colony forming units (CFU) of Moraxella catarrhalis have been measured after an application of photogem plus 632 nm diode laser irradiation. One ml of the bacterial suspensions have been incubated in the dark for 3h with various concentrations of photogem ($0.625{\sim}5.0_{\mu}g/mL$) and then irradiated with 632 nm diode laser ($15J/cm^2$). After, the PDT Moraxella catarrhalis suspensions ($50{\mu}L$) were inoculated on chocolate agar plate and cultured in the dark at $37^{\circ}C$, 5% $CO_2$ condition for 18h. The colony forming units off the bacteria were measured. Also transmission electron microscopy (TEM) was employed to evaluate the effect of otitis media pathogens by PDT. The nucleus of Moraxella catarrhalis was stained using green fluorescent nucleic acid dye thiazole orange and the fluorescence intensity of the nucleus was measured by flow cytometry. The PDT was effective in killing Moraxella catarrhalis at the photogem dose of $5.0_{\mu}g/mL$, respectively, As assessed by flow cytometry analysis the fluorescence intensity of the nucleus got lower after PDT. TEM result appeared to able to cause damage to the bacterial membranes. On the basis of these findings, bacterial photodynamic therapy with photogem can be considered to be a promising new therapeutic approach for OME.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.169-174
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• 2011

The synthesis of new pyrazolyl and cyclopropyl derivatives of purpurin-18 methyl ester and purpurin-18-N-butylimide 1a, 1b, 2a, 2b and 8 is described. The new compounds were characterized by NMR, UV-vis spectroscopy and mass spectrometry. UV-vis spectra of the new compounds showed long wavelength absorption of ranges 692 - 708 nm ($\lambda_{max}$). Photodynamic effects of the chlorin derivatives 1a, 1b, 2a and 2b were investigated by WST-1 assay in A549 cells, and showed good photodynamic activities with high photocytotoxicity and low cytotoxicity in the dark. In comparison between pyrazolyl and cyclopropyl derivatives, purpurin-18 methyl ester compounds 1a and 1b showed comparable photocytotoxicity result of the cell viabilities, otherwise, pyrazolyl derivative of purpurin-18-N-butylimide 2a showed better cell viabilities than those of cyclopropyl derivative 2b. And cyclopropyl derivative of purpurin-18-N-butylimide 2b showed higher dark cytotoxicity than that of others.

• Journal of Photoscience
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• v.9 no.2
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• pp.512-514
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• 2002

S-aminolevulinic acid (ALA) is a new kind drug used in photodynamic therapy. ALA-PDT have successfully used in superficial malignancies and some skin diseases. Here the effects of ALA-PDT were studied on leukemia cells and hepatoma cells to explore the application on different kind cancers. It was found from the fluorescence emission spectra, that after ALA incubation the sensitizer - protoporphyrin IX (PpIX) was endogenously produced in both leukemia and hepatoma cells. The fluorescence images showed that the PpIX distribute in cytoplasm. However the efficiency of ALA photodynamic inactivation to two cell lines was different. The leukemia cells were more sensitive for ALA-PDT than hepatoma cells, revealing that the ALA-PDT effect is cell line dependent. However by using ALA-Hexyl ester (He-ALA) instead of ALA, the cell photo-inactivation was improved. The PDT efficiency of He-ALA was 10 times high than that of ALA, showing He-ALA is a very promising drug in ALA-PDT.