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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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Endoscopic nasobiliary drainage (ENBD) is a well established mode of biliary decompression. Although ENBD is certainly an uncomfortable procedure with the potential risk of spontaneous dislocation or removal of the drainage catheter by disoriented patients, it has several advantages over endoscopic biliary drainage (EBD) using an indwelling stent. The current indications for ENBD are: (i) temporary drainage to treat obstructive jaundice and cholangitis caused by malignant or benign biliary stricture; (ii) urgent drainage to treat suppurative cholangitis primarily caused by common bile duct stones; (iii) temporary drainage after stone removal in patients with suspected incomplete clearance and/or with cholangitis; and (iv) biliary leaks that occur primarily after surgery, as well as other indications. Different types of nasobiliary catheters are currently available that have been designed with various diameters, shapes, and materials. However, the current catheters are not considered by most endoscopists to be sufficient. Further improvements are needed to achieve better drainage and better maneuverability.  相似文献   
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One of the pyrimidine compounds, 2-piperadino-6-methyl-5-oxo-5,6-dihydro(7H)pyrrolo[3,4-d]pyrimidine (MS-818), has neurotropic effects in vitro. Therefore, we studied the effect of MS-818 on the regeneration of the peroneal nerve in C57BL/6J mice after a crush injury. Two test groups, which received a daily intraperitoneal injection of 5 mg/kg or 10 mg/kg MS-818, respectively, were compared with controls, which received daily intraperitoneal injections of physiological saline, over a 14-day period. The maximum foot-width ratio (crushed side/uncrushed side) was obtained on days 1, 8 and 14 after the crush injury, and the various morphometric parameters were evaluated at both 5 and 10 mm distal to the proximal portion of the crush site. The significant effects of MS-818 included a larger maximum foot width (P<0.04) and a greater number of unmyelinated axons per nerve at both levels (P<0.003) in both test groups than in controls. MS-818 had no significant effects on body weight, the increase of total transverse fascicular area after the crush injury, the total number of myelinated fibers with their size distributions, or the number of nuclei of Schwann cells and macrophages. Therefore, we conclude that MS-818 promotes axonal sprouting and elongation after a crush injury in mice.  相似文献   
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We report a 3-year-old girl with hereditary motor and sensory neuropathy type III with a decrease in unmyelinated fibers. There have been few reports of such cases. The present findings suggest the possibility that the primary lesion in this disease is in the axons. We consider that more attention should be paid to the changes in unmyelinated fibers and axons in further studies on this disease.  相似文献   
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We investigated the clinical background of patients at Shin-Kokura Hospital who showed a positive culture of pleural effusion during the period from January 1998 through December 2002. Microorganism cultures of the pleural effusions of 127 patients were performed in this 5-year period. Seventeen patients showed a positive microorganism culture from a pleural effusion, and 12 of these patients (70.6%) were 60 years old or more. Ten patients were diagnosed with thoracic empyema. Thirteen patients had an underlying disease such as malignancy (5 cases), diabetes mellitus (4 cases), etc. A purulent effusion and a high concentration of lactic dehydrogenase (LDH) in the pleural fluid were more frequently recognized in the positive-culture group. A total of 21 strains of microorganism were isolated from the 17 patients, including 10 strains of Gram-positive cocci, 6 strains of Gram-negative bacilli, 3 strains of anaerobes, 1 strain of mycobacterium (Mycobacterium tuberculosis), and 1 strain of fungus. Susceptibility to antimicrobial agents was generally good for most of the microorganisms isolated. Of the 17 patients, chest-tube drainage was performed in 13, and 6 needed a surgical operation. Twelve patients improved, but 5 died. In this study, thoracic empyema accounted for 58.8% of the 17 cases with a positive culture of pleural effusion. Of the 10 thoracic empyema patients, 5 patients needed surgical treatment in spite of adequate antimicrobial treatment and chest-tube drainage. Our data indicate that thoracic empyema is still difficult to treat, and thus adequate and rapid treatment is needed for any pleural infection.  相似文献   
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