• Biomedical Science Letters
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• v.14 no.4
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• pp.269-274
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• 2008

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common nosocomial pathogens. It is associated with hospitals is now being isolated in the community. The aim of this study was to evaluate the antibacterial effect of photodynamic therapy using Photogem and 630 nm LED on MRSA and methicillin-sensitive Staphylococcus aureus (MSSA). The broth cultured MRSA and MSSA incubated with various concentrations of Photogem (500,50,5 and $0.5{\mu}g/mL$) for 4 h. Then 630 nm LED was given at $9\;J/cm^2$, $20{\mu}l$ of the exposed bacteria solution was inoculated onto agar plate. Plates were incubated for 24 hand colonies were counted. The PDT group was effective in killing MRSA and MSSA at the Photogem dose of $50{\mu}g/mL$. But MSSA is more sensitive than MRSA in photodynamic effect. Other groups (light only, sensitizer only, or no treatment) observed no bacterial cell killing. These results raise the possibility of using PDT with or without antimicrobial drugs to eradicate MRSA and MSSA. In order to confirm this result, we need to further study bacterial death mechanism and in vivo study.

• Biomedical Science Letters
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• v.15 no.3
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• pp.233-239
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• 2009

The aim of this study was to evaluate the photodynamic effect of various photosensitizing agents against methicillin-resistant Staphylococcus aureus (MRSA). MRSA was exposed to light from a 632 urn diode laser (15 J/$cm^2$) in the presence of various photosensitizer, such as photofrin, photogem, radachlorine and ALA. In vivo study was performed using ICR mice. Twenty eight mice had a standard wound ($100\;mm^2$) created on the dorsum, and MRSA was inoculated into the wound region. The four groups were classified as follows: (1) the untreated control group (bacteria alone), (2) the bacteria plus light group (15 J/$cm^2$), (3) the bacteria plus photofrin group (kept in the dark), and (4) the photodynamic therapy (PDT) group (bacteria, photofrin, and light). After photofrin (dose 1 mg/kg) injection, the experimental group was irradiated with 632 urn diode laser (15 J/$cm^2$) for 30 minutes after In vitro results of PDT showed the complete killing of MRSA at the photofrin, radachlorine, and photogem However, ALA-PDT was ineffective on MRSA viability. In vivo results showed that photofrin has therapeutic effect on the wound infection. These results demonstrate that selective lethal photosensitization of MRSA can be achieved using phofrin, photogem and radachlorin. Thus, PDT can inactivate MRSA survival.

• Journal of Veterinary Clinics
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• v.31 no.1
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• pp.66-69
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• 2014

Photodynamic therapy (PDT) is an effective method for infectious disease, but as yet, no clinical trial on otitis externa has been conducted in animals. This report describes 4 cases of PDT treatment on severe otitis externa in canine. Four canines were treated with various concentrations of 5-aminolevulinic acid hydrochloride (5-ALA) and with various J (second ${\times}$ power) and irradiated by light-emitting diode light source at 635 nm, respectively. After the PDT applications, canines incubated in the dark for 5 or 6 hr. All patients showed clinical resolution of otitis externa after PDT treatment at the dose of 0.16~0.3 g ALA and J (54~162 $J/cm^2$). On the basis of these findings, PDT can be considered to be a new therapeutic approach to severe otitis externa in canine.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.3
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• pp.124-132
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• 2011

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 $50{\mu}g/mL$ and energy density of $15J/cm^2$. 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.

• 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.

• Biomedical Science Letters
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• v.17 no.1
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• pp.79-84
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• 2011

Photodynamic therapy consists of a photosensitizer, suitable light source and oxygen. The excitation of the photosensitizer at a cancer mass results in oxidation which would ultimately reduce the mass via apoptosis. Millimeter wave (MMW) therapy has also been known to be effective on cancer cell mass reduction, human cell regeneration and immunity enhancement among the Russian clinicians and scientists. In the present study, the two modalities were combined to achieve synergistic effects while reducing the administration dosage of the photosensitizer, photogem, thus minimizing the side effects. The CT-26 adenocarcinoma cell mass was implanted on mice and the tumors were exposed to a simple MMW irradiation or a combined treatment of MMW and PDT. The treatments continued for 4 weeks and the size of the tumor was measured continuously. The significant therapeutic result of MMW was not found during 4 weeks, preferably more cancer recurrence possibility after MMW irradiation was observed. The results of this study suggest that the combination of MMW irradiation and photodynamic treatment should not be recommended. The result of the MMW treatment alone, however, displayed suppressive effect on cancer cell proliferation for both in vitro and in vivo. The results of the present study suggest that the millimeter wave therapy deserves a further study.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.2981-2987
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• 2011

A comparative study of the photodynamic and antioxidant activities of methyl pheophorbide-a (MPa, 1) and its transition metal(II) complexes (2-5) is described. Four transition metal complexes (palladium(II): 2, zinc(II): 3, cobalt(II): 4 and copper(II): 5) of MPa were prepared by reaction between the corresponding transition metal and 1, respectively, and were characterized by $^1H$-NMR and UV-vis spectroscopic and mass spectrometric analyses. In vitro results show a photodynamic therapy (PDT) efficacy with A549 cells might be attributed to a heavy atom effect of the transition metal complexes of MPa. Among them, 4 and 5 showed higher photodynamic activity than that of 1 at the concentration of 5 ${\mu}M$ at 24 h incubation after photoirradiation. The images of morphological change for 2-5 show evidence for the PDT effect with A549 cells. And the all transition metal complexes of MPa showed higher antioxidant activity than that of MPa, in which 4 showed the highest antioxidant activity.

• Tuberculosis and Respiratory Diseases
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• v.67 no.4
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• pp.338-344
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• 2009

In photodynamic therapy, a chemical photosensitizer is activated by light of a specific wavelength., Photodynamic therapy has been combined with bronchoscopy in patients who are ineligible for surgical resection in order to treat patients with early central lung cancer. Here, we describe 3 patients with early central lung cancer who were treated effectively using photodynamic therapy. Our experience shows that this approach is a useful modality in the therapy of these types of tumors.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.124-129
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• 2011

The role of the ferric uptake regulator (Fur) of Helicobacter pylori in the oxidative stress was investigated in this study. A fur knockout mutant of H. pylori was constructed by replacing the fur gene with an aphA (kanamycin resistant marker) gene. Photodynamic therapy using methylene blue (MB) and 660 nm light was chosen to induce oxidative stress. The bactericidal effect of photodynamic therapy (PDT) was compared between wild type H. pylori and fur knockout mutant H. pylori. The degree of oxidative damage of DNA was confirmed using alkaline gel electrophoresis and an assay of 8-hydroxy-2-deoxyguanosine (8-OHdG). In control groups, the number of viable cells was maintained constantly during experiment. After PDT, the mutant H. pylori showed 10,000 times decreased viable cell number compared with wild type H. pylori. Depending on the exposure time of 660 nm light, the 3-fold increase in the concentration of 8-OHdG was observed in mutant H. pylori. The results of this study showed that H. pylori's Fur protein may play a role in oxidative stress induced by PDT.

• 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.