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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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The requirement for endoscopic access to a stricture is a major limitation of the endoscopic dilatation for the treatment of strictures in the gastrointestinal tract. We have developed the double‐balloon enteroscopy method that enables visualization of the entire small bowel. In addition, double‐balloon enteroscopy has a potential for the interventional therapy including dilatation of strictures. We present here a case of jejunal strictures in a 47‐year‐old woman with Crohn's disease successfully treated with a balloon catheter in combination with double‐balloon enteroscopy. Balloon dilation with double‐balloon enteroscopy is a promising method for the treatment of small bowel strictures in Crohn's disease.  相似文献   
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We used morphological, biochemical and immunohistochemical methods to assess the response of Müller cells after experimental lensectomy-vitrectomy in rabbits. We observed widened intercellular spaces between the Müller cells and nerve fibers of ganglion cells, and increased electron opacity in the Müller cells of eyes injected with silicone oil. No apparent morphological changes were detected in the Müller cells of air-injected eyes. The specific and total activities of Müller cell-marker enzymes (glucose 6-phosphatase and glutamine synthetase) showed an initial increase, followed by a decrease. Glial fibrillary acidic protein immunoreactivity was not found in the Müller cells of the normal rabbit retina but was exhibited after surgery. Our results showed that markers of Müller cells associated with glycogenolysis and/or gluconeogenesis, glutamate-glutamine cycle and cytoskeletal protein metabolism were affected by the experimental lensectomy-vitrectomy.  相似文献   
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PURPOSE: The association of BRCA2 polymorphisms at codon 372 [Asn (N)/His (H)]and codon 784 [Met (M)/Val (V)] with breast cancer risk was evaluated in Japanese women. In addition, the prognostic significance of these polymorphisms was studied in breast cancer patients. EXPERIMENTAL DESIGN: A case-control study was conducted to examine the association of the BRCA2 N/H372 polymorphism and M/V 784 polymorphism with breast cancer risk (cases = 149, controls = 154). The prognostic significance of these polymorphisms was evaluated in 139 patients with primary breast cancer. RESULTS: No significant association was observed between the N/H372 polymorphism and breast cancer risk. In contrast, a significant increase in breast cancer risk (odds ratio, 2.03; 95% confidence interval, 1.07-3.87) was observed in carriers of the variant allele (V784) of the M/V784 polymorphism as compared with noncarriers after adjustment for the classical risk factors, age, family history, parity, body mass index, and so forth. Among breast cancer patients, various clinicopathological parameters including menopausal status, tumor size, lymph node status, histological grade, and estrogen-receptor status were not significantly different between the carriers and noncarriers of the variant allele with regard to both N/H372 and M/V784 polymorphisms. The N/H 372 polymorphism was not significantly associated with patient prognosis. On the other hand, breast cancer patients carrying the variant allele of M/V784 polymorphism showed a significantly (P = 0.014) lower 3-year disease-free survival rate (63%) than noncarriers (92%). Multivariate analysis has revealed that the M/V784 polymorphism is a significant prognostic factor, being independent of the other conventional prognostic factors such as lymph node status and estrogen receptor status. CONCLUSION: These results suggest that the M/V784 polymorphism, but not the N/H372 polymorphism, would be useful in the selection of women at high risk for developing breast cancer and would also serve as a clinically useful prognostic factor in breast cancer patients.  相似文献   
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We previously proposed a quantitative approach to assess donor organs for cadaver renal transplantation. To improve on our original scoring system, we studied 34 324 patients who received cadaver renal transplants from adult donors between 1994 and 1999 and were reported to the UNOS Scientific Renal Transplant Registry. A scoring system was developed from five donor variables (age, 0-25 points; history of hypertension, 0-4; creatinine clearance before procurement, 0-4; cause of death, 0-3; HLA mismatch, 0-3) that showed a significant correlation with renal function and long-term graft survival. Cadaver kidneys were stratified by cumulative donor score: grade A, 0-9 points; grade B, 10-19; grade C, 20-29; and grade D, 30-39. The influence of donor score on renal function and graft survival was most severe above 20 points, designated 'marginal' kidneys. In summary, a donor scoring system developed from a large population database was useful in predicting outcome after cadaver renal transplantation. The improved system provides a quantitative approach to evaluation of marginal kidneys and may improve allocation of these organs in cadaver renal transplantation.  相似文献   
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We report a 52 year-old man presenting with an acute considerable hair loss induced by carbamazepine (CBZ). The remarkable scalp hair loss started within a week after CBZ administration. There was no evidence of dermatitis or allergic reaction, or other cause for the hair loss. The serum concentration of CBZ was 8.6 microg/ml (therapeutic range 8-12 microg/ml). CBZ was discontinued, and the hair loss stopped within several days with new hair growth. Medication-induced hair loss is an occasional adverse effect of many drugs used for neuropsychological diseases. CBZ also induces hair loss and its frequency was reported below 2%. Only a limited number of detailed case reports describing CBZ-induced hair loss were available, and we found these cases could divide into two groups with regard to a delay in starting hair loss after administration of CBZ. In one group, the hair loss started within a week suggesting anagen effluvium and in another it started after two or three months suggesting telogen effluvium. This finding suggests the causative mechanism of CBZ-induced hair loss is not unitary.  相似文献   
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OBJECTIVE: To evaluate the influence of the age at disease onset on the clinical symptoms, laboratory findings, treatment, and complications of microscopic polyangiitis (MPA). PATIENTS: From 1999 to 2001, we encountered 4 MPA patients with disease onset at age 65 or older (average 77.3, all were female: the elderly group). For comparison, 4 MPA patients with disease onset a 64 years or younger (average 44.7, two were male: the non-elderly group) were used. RESULTS: There was no statistically significant difference in clinical features between the two groups. All patients in the elderly group were referred to our hospital, because of fever of unknown origin or suspicion of connective tissue disease. The elderly group had a longer duration from the first admission to the start of treatment. Renal biopsies were done in all of the non-elderly group and one of the elderly group. The diagnosis of the other 3 patients of the elderly group was based on muscle or nerve biopsy, showing necrotizing vasculitis. At the time of diagnosis, antibodies to myeloperoidase (MPO-ANCA) were positive in 7 of 8 patients (87.5%). 2 patients of the non-elderly group were died of heart failure and hepatic failure by cyclophosphamide (CYC). The other 6 patients achieved substantial improvement. CONCLUSIONS: Muscle or nerve biopsy helped clinical management of elderly patients when renal biopsies could not be done. IVCY was relatively safe and effective treatment for MPA in elderly as well as non-elderly patients.  相似文献   
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