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1.

Background

Photosensitizers used for photodynamic therapy (PDT) to treat dermatologic disease are metabolized into mainly protoporphyrin IX (PpIX), which has five absorption wavelength peaks: 410?nm, 510?nm, 545?nm, 580?nm, and 630?nm. Although only red light around 635?nm and blue light around 400?nm are used as light sources for PDT, the efficiency of PDT might be improved by using multiple wavelengths, including those that correspond to the other absorption peaks of PpIX. Furthermore, because the target disease often occurs on the face, a flexible-type light-source unit that can be fitted to the lesion without unnecessarily exposing the mucous membranes, e.g., the eyes, nostrils, and mouth, is preferred.

Objective

We investigated the efficacy of a flexible light-emitting diode (LED) unit that emits multiple wavelengths to improve PDT effects.

Methods

HaCaT cells were incubated with 5-ALA and subsequently irradiated with either a single wavelength or sequentially with two wavelengths. Cell viability and reactive oxygen species were analyzed. Nude mice were implanted with COLO679 cells by subcutaneous injection into the flank. 5-ALA was subcutaneously injected into the tumor. The tumor was irradiated with 50?J/cm2 (day 0) and assessed daily until day 21.

Results

The synergistic PDT effects of dual-wavelength irradiation and reactive oxygen species production were highest with the 405-nm and 505-nm wavelength combination. This dual wavelength combination was also the most effective in vivo.

Conclusion

We could therefore conclude that dual-wavelength PDT is an efficient strategy for improving the therapeutic effects of PDT. Using a flexible LED unit is expected to achieve more uniform irradiation of uneven areas.  相似文献   
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We evaluated the therapeutic efficacy of miconazole (MCZ, Florid-F inj.), a new antifungal agent for parenteral use, in deep-seated fungal infections of respiratory tract system. A daily dose of 400-1,800 mg of MCZ was given intravenously for 12-38 days (mean: 23.4 days) to 7 patients: 2 patients with pulmonary aspergillosis, 1 patient with bronchial aspergillosis, 1 patient with pulmonary candidiasis and 3 patients with candidemia. One additional patient with pulmonary aspergillosis received three instillations of 20 mg of MCZ into the thoracic cavity. The clinical effects were excellent in 1, good in 4 and poor in 3 patients. The efficacy rate was 100% in 5 cases with respiratory fungal infections but 3 cases with candidemia did not respond well to the treatment. Four strains each of Aspergillus sp. and Candida sp. were identified as causative organisms. Seven of the 8 strains were eradicated by administration of MCZ. Side effects observed were irritation and heat in a leg in 1 patient, hyperlipoidemia in 2 patients and eosinophilia in 1 patient. The adverse reactions disappeared after the completion of the therapy. From the above results, we conclude that MCZ is one of the most useful antifungal agents for parenteral use as a first choice on deep-seated fungal infections in the respiratory tract.  相似文献   
4.
The underlying mechanism involved in the interaction between neutrophil elastase inhibitors and tachykinins has not been elucidated. In this study we have examined the effects of sivelestat, a neutrophil elastase inhibitor, on the in vitro responses of airways from lipopolysaccharide (LPS)-untreated or -treated guinea-pigs to substance P. Substance P (0.01-30 micromol/l) produced concentration-dependent contractions of both tracheal and bronchial ring preparations of LPS-untreated or -treated guinea-pigs. Responsiveness to substance P in these isolated airway preparations was augmented by either epithelium removal or LPS treatment. In epithelium-intact tracheal ring preparations isolated from LPS-untreated guinea-pigs, sivelestat (100 micromol/l) significantly inhibited substance P-induced contractions. The inhibitory action was markedly attenuated by pretreatment with L-NAME (100 micromol/l) or indomethacin (2 micromol/l), and was almost undetected following removal of the epithelium. On the other hand, in bronchial ring preparations isolated from LPS-untreated guinea-pigs, sivelestat had only a very slight effect on substance P-induced contraction of the epithelium-intact preparation, whereas sivelestat greatly inhibited contraction in epithelium-removed bronchial ring preparations. In LPS-treated guinea-pigs, whether the epithelium was intact or not, sivelestat significantly inhibited the substance P-induced contraction of bronchial ring preparations. Pretreatment with L-NAME (100 micromol/l) or indomethacin (2 micromol/l) did not affect the inhibitory effect of sivelestat in bronchial ring preparations. In conclusion, epithelium removal or LPS treatment induced hyperreactivity to substance P in the guinea-pig airway. Sivelestat caused epithelium-, nitric oxide- and prostaglandin-dependent inhibition of the substance P-induced contraction of isolated guinea-pig tracheal ring preparations. In contrast, the inhibitory effect of sivelestat on substance P-induced contraction of guinea-pig bronchial ring preparations is mediated by epithelium-, nitric oxide- and prostaglandin-independent mechanisms. Sivelestat may be effective in reducing the airway hyperresponsiveness to tachykinins induced by epithelial injury as occurs in LPS-mediated inflammatory lung diseases.  相似文献   
5.
PURPOSE: This study evaluated the bone volume, height, and width that can be obtained in alveolar ridge augmentation using titanium mesh and autogenous bone particles in patients with cleft lip/palate. PATIENTS AND METHODS: Subjects were 15 patients with cleft lip/palate requiring tertiary bone graft for implant therapy. Computed tomography (CT) scans were taken before removing the mesh, from 1 to 21 months after bone grafting. Forty-three reconstructed images corresponding to the positions for implant placement were selected for this study. The percent defect filled with bone (%BONE), defined as the percentage of newly formed bone in the space created by the mesh, was measured for image analyses. In linear analyses, 4 parameters were used: increased bone height (IBH), percent increased bone height (%IBH), increased bone width (IBW), and percent increased bone width (%IBW). Factors influencing the quantitative data and the clinical courses of placed implants were also explored. RESULTS: The average %BONE was 91.1%. IBH averaged 4.4 mm, whereas %IBH averaged 88.5%. IBW averaged 4.6 mm, whereas %IBW averaged 86.4%. Little correlation was present between the quantitative data and patient age, or time interval. A significant correlation was identified between the data for span of the grafted area and %BONE (correlation coefficient value = -0.36). However, the diminishing rate was very low. No implants were lost postoperatively. CONCLUSIONS: Alveolar ridge augmentation with titanium mesh and autogenous bone particles from the anterior iliac crest has very high predictability as a preimplant procedure in patients with cleft lip/palate.  相似文献   
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A 72-year-old fisherman who was positive for the HCV antibody developed an annular, erythematous, infiltrated lesions on sun-exposed areas. The lesions were diagnosed as annular elastolytic giant cell granuloma both clinically and histologically. Topical corticosteroid and cryotherapy with liquid nitrogen for several months failed to improve the lesions. We then started dapsone, a known anti-oxidant, at 50 mg/day. A month later, the margins of the erythematous lesions faded, and the infiltration gradually decreased. No recurrence has been observed for one year after the start of the therapy. Anti-oxidative therapy appears to be effective for annular elastolytic giant cell granuloma and could be an alternate therapy for refractory granulomatous disease.  相似文献   
9.
Since somatostatin is a local hormone controlling gastric acid secretion and gastrin release, quantitative histopological distribution of the G-cells and D-cells in the canine whole stomach was investigated by the specific immunoperoxidase staining technique. The G-cells were identified only in the pyloric antrum and the estimated total number of G-cells was 15.5 X 10(6) cells. Most of the D-cells were also found in the pyloric antrum but a few were found scattered diffusely throughout body and fundus of the stomach. The estimated total number of D-cells was 11 X 10(6) cells in the pyloric antrum and 4 X 10(6) cells in the corpus and fundus. The G-/D-cell ratio in the antrum was 1.4:1. The number of G-cells as well as D-cells per unit mucosal surface area was significantly higher on the greater curvature and the proximal part of the antrum than on other areas of the antrum. Thus, the pattern of distribution in G-cells was similar to that of D-cells and there was a highly significant correlation between G- and D-cells per unit mucosal surface area. It would appear that under normal conditions, the number of G- and D-cells in the antrum are in good balance and may play an important role in the control mechanisms related to gastric secretion.  相似文献   
10.
To clarify the genetic aberrations involved in the development and progression of hepatitis C virus-associated hepatocellular carcinoma (HCV-HCC), we investigated DNA copy number aberrations (DCNAs) in 19 surgically resected HCCs by conventional CGH and array CGH. Conventional CGH revealed that increases of DNA copy number were frequent at 1q (79% of the cases), 8q (37%), 6p (32%), and 10p (32%) and that decreases were frequent at 17p (79%), 16q (58%), 4q (53%), 13q (42%), 10q (37%), 1p (32%), and 8p (32%). In general, genes that showed DCNAs by array CGH were usually located in chromosomal regions with DCNAs detected by conventional CGH analysis. Increases in copy numbers of the LAMC2, TGFB2, and AKT3 genes (located on 1q) and decreases in copy numbers of FGR/SRC2 and CYLD (located on 1p and 16q, respectively) were observed in more than 30% of tumors, including small, well-differentiated carcinomas. These findings suggest that these genes are associated with the development of HCV-HCC. Increases of MOS, MYC, EXT1, and PTK2 (located on 8q) were detected exclusively in moderately and poorly differentiated tumors, suggesting that these alterations contribute to tumor progression. In conclusion, chromosomal and array CGH technologies allow identification of genes involved in the development and progression of HCV-HCC.  相似文献   
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