We compared the Phototoxicity effect of the cancer cells and normal cells by PDT (photodynamic therapy) used a laser diode as an optical source. It was investigated the accumulation of Talaporfin in cancer cells after incubation in solution and confirmed Talaporfin can kill cancer cells selectively by photo-irradiation. In the experiment, the WFB (rat fetus fibroblast) as normal cells and W31 as cancer cells were used. W31 is the malignant transformed cell from WFB. Fluorescence image was measured from cancer cells incubated in Talaporfin solution with a fluorescence microscope. It was found that the fluorescence peak of Talaporfin in cell has red-shifted and the lifetime which measured by streak-camera was slightly increased as compared to Telaporfin solution. The reason is the Talaporfin combined the bio-molecules in the cancer cell and the emission situation is changed. The measurement of the optical absorbance of Telaporfin in the cell, it confirmed that the Talaporfin could be accumulated in cancer cells more than in normal cells. Furthermore, the viability of the cells was assessed by use Trypan Blue Stain after PDT. It was clarified that Talaporfin could be accumulated in cancer cells more than in normal cells and lead to selective cancer cell death.

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Objective Photodynamic therapy (PDT) using 5-aminolevulinic acid (5-ALA) is a new therapeutic modality for malignant glioma. This study is designed to evaluate acute morphological and histological changes of glioma cells after 5-ALA mediated PDT using fluorescence microscopy and three dimensional spheroid models.
Methods Monolayer cultures and spheroids (small and large sizes) of C6 (rat glioma cell line) and U251MG (human glioma cell line) cells were co-incubated for 4 hours with 5-ALA (100μg/ml) and irradiated using a diode laser (635±5 nm, 5-100 mW/cm², total light dose 2.5-50 J/cm²). Growth kinetics of the spheroids were followed for 7 days after PDT and morphological changes were assessed by phase-contrast microscopy. In addition to hematoxylin-eosin (H.E.) and the terminal deoxynucleotidyl transferase-mediated dUTP-FITC nick end-labeling, various fluorescent dyes including Calcein AM, Ethidium homodimer (ethD-1), Annexin V-FITC, Propidium iodide (PI) and Hoechst33342, were used to clarify the mechanism of cell death after PDT.
Results Although PDT spheroids of both cell lines showed growth inhibition during the first few days, resumption of spheroid growth on day 3 after irradiation was observed in most spheroids. H.E staining showed cells with condensed chromatin within the superficial layer of the PDT spheroids. In the PDT groups, monolayer cells in the irradiated area were negative for Calcein AM and clearly positive for EthD-1. In C6 PDT spheroids, the outer layer of the spheroid was negative for Calcein AM and positive for EthD-1. In monolayer cells, cells in the irradiation area in PDT groups were positive for PI and negative for Hoechst33342.
Conclusion Light and fluorescence microscopic findings suggested necrotic cell death as an anti-tumor effect in the acute phase after PDT. These findings were observed in both C6 and U-251MG monolayer culture cell and spheroids. Although various total light doses resulted in significant differences in the growth rate of spheroids after PDT, resumption of spheroid growth occurred in most spheroids.

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The biomacromolecules damage through photosensitized reaction is important process of photodynamic therapy. In this study, the photosensitized reaction of diethyleneglycoxyP(V)tetraphenylporphyrin (DEP(V)TPP), a cationic porphyrin, was examined. The study of near-infrared emission measurements demonstrated the photosensitized singlet oxygen (¹O₂) generation by DEP(V)TPP (quantum yield: 0.41 in ethanol). The UV-Vis absorption and circular dichroism spectra measurements showed that DEP(V)TPP forms 2:1 binding complex with human serum albumin (HSA). The fluorescence quenching of DEP(V)TPP by HSA showed the electron transfer (ET) from amino acid residue of HSA to photoexcited DEP(V)TPP. These results suggest that DEP(V)TPP has ability to damage protein through dual mechanisms, ¹O₂ generation and ET. Photoexcited DEP(V)TPP decreased the fluorescence intensity of the tryptophan moiety of HSA, indicating the decomposition of amino acid of HSA. The tryptophan oxidation by photoexcited DEP(V)TPP was partially inhibited by sodium azide, a strong quencher of ¹O₂, but a high concentration of sodium azide could not completely inhibit this amino acid oxidation. These findings suggest the partial contribution of ET to protein photodamage by DEP(V)TPP. Since the ET mechanism does not absolutely require oxygen, DEP(V)TPP can act in the condition of lower oxygen concentration. In conclusion, DEP(V)TPP binds to HSA and induces photo-oxidation of amino acid via both mechanisms, oxygen-independent ET and ¹O₂ generation.

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Photodynamic therapy (PDT) using 5-ALA has been generally accepted as one of the therapies to superficial malignant skin tumors. However, costly excimer-dye laser frequently used to PDT so far in Japan is not practical to use in dermatology clinic. In this study, we evaluated the effectiveness of ALA-mediated PDT using Super Lizer^TM (Tokyo Iken, Tokyo, Japan) equipped with band-pass filter to 17 patients with superficial malignant skin tumors (12 cases of actinic keratosis and 5 cases of Bowen′s disease).
Among them, 9 cases(7 cases of actinic keratosis and 2 cases of Bowen′s disease) were successfully treated completely and other 8 cases (5 cases of actinic keratosis and 3 cases of Bowen′s disease) showed partial remission after single or repeated PDT. Taken together, Super Lizer^TM which is easy to handle and move, less expensive compared to excimer-dye laser would be useful machine for PDT in dermatology.

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Over the last 4 decades, several laser technologies have been introduced to challenge the traditional standard urological procedures. The improvement in laser technology has apparently led to the development of promising minimally invasive treatment options in certain area of urological practice, such as lithotripsy and prostatectomy. Those techniques, which could stand the test of time, remained as modern gold standard procedures. Herein is reviewed the characteristics and assessment of several procedures based on laser technology in urological practice.

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Laser has a sufficiently strong power even though the delivery system is narrow. The Ho:YAG laser can be used as safe and effective energy source with excise knowledgment of the laser wavelength. The Ho:YAG laser has very wide application as it is versatile laser that can be employed for both soft and hard tissues because of its wavelength. The Ho:YAG laser is the most powerful and efficient energy source of lithotriptor for urolithiasis.
The applications of Ho:YAG laser in stone treatment are described in this paper.

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Holmium Laser Enucleation of the prostate (HoLEP) was first introduced by Gilling et al. in 1998. Outcomes have been as good as traditional methods with fewer side effects and shorter recovery times. HoLEP will become an excellent surgical option for BPH patients.

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Transurethral resection of the prostate (TURP) is the established and standard surgical treatment for surgical procedure for lower urinary tract obstruction due to benign prostatic hyperplasia (BPH). In recent years, various technical innovations have been made, seeking surgical procedures that are technically easier to perform for urologists and less invasive to patients as we enter an aging society. We investigated the safety and efficacy of Photoselective Vaporization of the Prostate (PVP), new minimally invasive laser treatment for BPH. 97 patients underwent Photoselective Vaporization of the Prostate (PVP) using 80 W Potassium-titanyl-phosphate (KTP) laser. KTP laser vaporization was performed successfully in all 97 patients. There was minimal blood loss and none of patients need blood transfusion. No major complication occurred intraoperatively or postoperatively. Improvement in micturition status was observed immediately after PVP and was maintained over a period of 12 months. Postoperative side effect was mild, and included transient dysuria. Photoselective Vaporization of the Prostate (PVP) using 80 W KTP laser for benign prostatic hyperplasia (BPH) proved to be an effective and safe procedure for our patient including those treated with oral anticoagulants. While describing our experience and clinical results, the efficacy and the possibilities of PVP by the newest literature are discussed.

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TURP is a gold standard in various treatments for benign prostatic hyperplasia. However, this procedure would not be perfectly less invasive because some complications such as bleeding have not been solved.
Laser prostate ablation has been recently developed to eliminate these problems. Laser diode ablation using EVOLVE SLV^TM was first reported in 2007. We reported regarding the first clinical trial of laser prostate ablation in Japan.
Five cases underwent laser ablation using EVOLVE SLVT^TM with full agreement to clinical trial. All cases have experienced urinary retention. Very few bleeding was observed during operations. Urethral catheter could be removed within 24 hours in four cases. The improvement of IPSS and QOL score has been kept in three months after operation, although maximum urine flow was less than 10 ml/sec in four cases.
Laser prostate ablation using EVOLE SLV^TM was done safely in 5 cases. This procedure would be an important alternative in the treatment of benign prostate hyperplasia, although the evaluation of long term follow-up would be required.

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