• KSBB Journal
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• v.22 no.5
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• pp.318-321
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• 2007

Photodynamic therapy (PDT) is a targeted-tumor treatment system using a photosensitizer, light and oxygen to treat malignant tumor. We have investigated the cytotoxicity of 4 types of phthalocyanine derivative (silver phthalocyanine, iron (III) phthalocyanine, copper (II) phthalocyanine, nickel (II) phthalocyanine) against lung and breast cancers based on photodynamic therapy. As a result, phthalocyanine derivatives indicated a higher anticancer activity on a breast cancer cell line. Among the tested phthalocyanines, silver phthalocyanine (AgPc) showed a lower cytotoxicity against a normal cell line. In addition AgPc gave a good color characteristic when it is solubilized in water. Finally AgPc was selected as a potential antitumor agent for breast cancer.

• Journal of Life Science
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• v.28 no.11
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• pp.1321-1331
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• 2018

The aim of this study was to separate the photosensitizer that induces apoptosis of U937 and SK-HEP-1 cells from Nostoc commune. Dried N. commune was extracted with $CH_2Cl_2/MeOH$ (1:1) to separate the photosensitizer using various chromatographic techniques. The isolated compound was identified as pheophytin a ($C_{55}H_{74}N_4O_5$) with a molecular weight of 870. Its photodynamic activities were assessed under different irradiation conditions (light and non-light) at the same concentration range of $1.15-23.0{\mu}M$. The apoptosis inducing activity in U937 or SK-HEP-1 cells appeared only in the light. The mechanisms underlying the pheophytin a-mediated photodynamic inhibition of cancer cells were further investigated by examining cell morphology changes, cytotoxicity, caspase-3/7 activity, fluorescence staining, flow cytometry analysis, and DNA fragmentation in these two cell lines. The positive control and the light irradiation group showed typical apoptotic responses, including morphological changes, cytotoxicity, caspase activity, nucleus shrinkage owing to chromatin condensation, DNA laddering, and the presence of apoptotic bodies. Cytotoxicity markedly increased in a dose-dependent manner after a 12 hr exposure. Caspase-3/7 activity was higher in U937 cells than in SK-HEP-1 cells. Apoptosis induction therefore appeared to be both concentration- and light-dependent. In conclusion, pheophytin a, isolated from the blue green alga N. commune, had a photodynamic apoptosis-inducing effect on U937 and SK-HEP-1 cells. The findings reported here can be used as basic data for the development of next-generation photosensitizers from N. commune.

• Journal of radiological science and technology
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• v.45 no.2
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• pp.165-170
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• 2022

Staphylococcus aureus is a major pathogen that causes clinical infections in humans and can also cause massively colonized in lesion skin, particularly in atopic dermatitis patients. This study investigated the effects of photodynamic inactivation with radachlorin and diode laser irradiation on the viability of S. aureus in vitro and assessed the effects of the dose of laser transmission. In the PDI group, 5 𝜇L of S. aureus suspension and 5 𝜇L of radachlorin were inoculated in a 55 mm petri dish (63.6 cm²). The samples were placed in a 37° incubator for 30 min and then irradiated with light (660 nm diode laser). After laser irradiation, the cells were stored for 24 h at 37° in an incubator with 5% CO2, and the number of colonies was counted. All CFU/mL of S. aureus were reduced by diode laser in the presence of radachlorin, with a killing rate of 87.9% at an energy dose of 9 J/cm². This study contribute to treat colonized with S. aureus in atopic dermatitis patients and wound infections by providing information on the optimal dose of laser transmission using PDI to eliminate S. aureus.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.6
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• pp.49-56
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• 2007

In this paper, the development of excitation light source is proposed for excitation light of the photodynamic therapy of cancer. Since the selection of the wavelength band of excitation light has an interrelation with fluorescence generation according to the selection of a photosensitizer. This study aims at designing and evaluating light source that can stably generate light with various kinds of wavelengths in order to make possible photodynamic diagnosis using a photosensitizer and diagnosis using auto-fluorescence. The light source device was a Xenon lamp and filter wheel, composed of an optical output control through iris and filters with several wavelength bands. It also makes the inducement of auto-fluorescence possible because it is designed to generate a wavelength band of 380-420nm, 430-480nm, 480-560nm. The transmission part of the light source was developed to enhance the efficiency of light transmission. To evaluate this light source device by KFDA#s technical reference, the characteristics of the light output and wavelength band were found.

• Restorative Dentistry and Endodontics
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• v.33 no.2
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• pp.141-147
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• 2008

This study was aimed to develop an instrument for real-time measurement of fluid conductance and to investigate the hydrodynamics of dentinal fluid. The instrument consisted of three parts; (1) a glass capillary and a photo sensor for detection of fluid movement, (2) a servo-motor, a lead screw and a ball nut for tracking of fluid movement, (3) a rotary encoder and software for data processing. To observe the blocking effect of dentinal fluid movement, oxalate gel and self-etch adhesive agent were used. BisBlock (Bisco) and Clearfil SE Bond (Kuraray) were applied to the occlusal dentin surface of extracted human teeth. Using this new device, the fluid movement was measured and compared between before and after each agent was applied. The instrument was able to measure dentinal fluid movement with a high resolution (0.196 nL) and the flow occurred with a rate of 0.84 to 15.2 nL/s before treatment. After BisBlock or Clearfil SE Bond was used, the fluid movement was decreased by 39.8 to 89.6%.

• Restorative Dentistry and Endodontics
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• v.36 no.4
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• pp.306-312
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• 2011

Objectives: This clinical study evaluated the effect of light activation on the whitening efficacy and safety of in-office bleaching system containing 15% hydrogen peroxide gel. Materials and Methods: Thirty-three volunteers were randomly treated with (n = 17, experimental group) or without light activation (n = 16, control group), using Zoom2 white gel (15% $H_2O_2$, Discus Dental) for a total treatment time of 45 min. Visual and instrumental color measurements were obtained using Vitapan Classical shade guide and Shadepilot (DeguDent) at screening test, after bleaching, and 1 month and 3 month after bleaching. Data were analyzed using t-test, repeated measure ANOVA, and chi-squared test. Results: Zoom2 white gel produced significant shade changes in both experimental and control group when pre-treatment shade was compared with that after bleaching. However, shade difference between two groups was not statistically significant (p > 0.05). Tooth shade relapse was not detected at 3 months after bleaching. The incidence of transient tooth sensitivity was 39.4%, with being no differences between two groups. Conclusions: The application of light activation with Zoom2 white gel system neither achieved additional whitening effects nor showed more detrimental influences.

• Journal of Chest Surgery
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• v.42 no.3
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• pp.371-374
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• 2009

A 36-year-old woman with a history of spontaneous abortion and photosensitivity was admitted to our hospital with periumbilical pain and lower extremity edema. The preoperative CT scan revealed massive inferior vena cava thrombus, which extended from the suprarenal portion of the vena cava to the hepatic vein. The laboratory data showed an elevated level of anticardiolipin antibody, which suggested the diagnosis of antiphospholipid syndrome. After medical management, she underwent an operation for removal of an vena cava thrombus by performing cavectomy and thrombectomy. After the operation, she has been taking oral anticoagulation and she is doing quite well at 9 months after her operation.

• Tuberculosis and Respiratory Diseases
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• v.57 no.4
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• pp.358-363
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• 2004

Background : Photodynamic therapy (PDT) involves the use of photosensitizing agents for treatment of malignant disease. PDT is approved by the U.S. Food and Drug Administration for the endobronchial microinvasive nonsmall cell lung cancer and for palliation in patients with obstructing tumors. We report our experience and results of PDT in lung cancer. Method : Ten patients with lung cancer who were diagnosed in Chosun university hospital by histologic confirm through bronchoscopy were included between August 2002 and May 2003. The photosensitizer (Photogem$^{(R)}$, Lomonosov institute of Fine Chemical, Russia/dose 2.0 mg/kg body weight) was injected 48 hours prior to the PDT session. For PDT with the photosensitizer (Photogem$^{(R)}$), Diode LASER system (Biolitec Inc., Germany, wavelength; 633nm) were used. PDTs were done at 48-72 hours after photogem injection. Follow up bronchoscopy and chest X-ray or thorax computerized tomography were done for evaluate PDT response. Results : 9 of 10 patients with endobronchial obstruction showed partial remission with bronchus opening after PDT. Direct reaction of the tumor to PDT was similar in despite of its localization. It was as follows; edema, hyperemia, in-situ bleeding, fibrin film occurrence. Any other complications such as sunburns of skin, inflammation within the PDT zone were not occurred by the end of the fourth week. Conclusion : In the advanced endobronchial disease, PDT has been shown to be useful in treating endobronchial tumors that are causing clinically significant dyspnea or are likely to progress and lead to further clinical complications, such as postobstructive pneumonia.