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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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Factors associated with levels of physical activity at work and during leisure time were analyzed among 577 subjects who had been selected as population controls for a case-control study by random selection from telephone directories. The intensity of physical activity at work was inversely associated with body mass index, the proportion of professionals & managers, consumption of western style breakfast, coffee, butter/margarine, and whisky; and positively associated with rice intake. Frequency of physical activities during leisure time was positively associated with consumption of vegetables, fruits, mushrooms, milk, cheese and coffee, and moderation in eating; and inversely associated with rice intake and the prevalence of gastrointestinal symptoms and medication. The association of physical activity with these factors should be considered in studying its relationship to disease risk.  相似文献   
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We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM.  相似文献   
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Thyroid function tests were studied in 105 severely disabled children. Fifty-four cases (53%) showed following abnormalities. Serum TSH concentration was increased in 2 cases. Both serum T4 and T3 levels were decreased in 18 cases (17%). Only the serum T4 level was decreased in 25 cases (24%). Only the serum T3 level was decreased in 10 cases (9.5%). Two patients showed primary hypothyroidism. Two patients (monozygotic twins) were suspected to have subclinical hypothalamic-pituitary hypothyroidism caused by septo-optic-dysplasia. Abnormal thyroid functions were caused by anticonvulsants in most patients. The serum T4 level was correlated with the number of anticonvulsants, but not correlated with motor performance (daily activity) or feeding function. Four patients who had low T4 level or low T4 and T3 levels were received L-thyroxine supplementation, but no clinical improvement was observed. The serum TSH concentration was decreased and the TRH test showed hyporeaction in all of these cases. The low T3 level and normal T4 level were not related to anticonvulsant administration. Two of these patients were in poor nutritional condition, resulting in so called low T3 syndrome.  相似文献   
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Two distinct regions required for both contact hemolysis and entry into LLC-MK2 cells were cloned into Escherichia coli from the Shigella sonnei form I plasmid, pSS120. The first region was cloned into an E. coli HB101 strain containing noninvasive Tn1 insertion mutants of the form I plasmid, and expression of ipa (invasion plasmid antigen) gene products was restored. The plasmid carrying the first region was then transformed into E. coli lacking the form I plasmid, and additional DNA fragments from the form I plasmid were cloned into the same recipient on compatible vectors. Five of these double transformants were found to be positive for contact hemolysis activity. Restriction analysis of these five clones indicated that the previously reported ipa locus and the invA locus were present on the second plasmid region. Only the strains carrying both of these regions were active in contact hemolysis and cell invasion assays. Several proteins, including the a, b, c, and d proteins encoded by the ipa genes, were detected in the double transformants by Western blot (immunoblot) analysis with serum of a monkey convalescing from shigellosis. A positive regulator was suggested to exist in the first region, since the amounts of most of these proteins were simultaneously increased in the presence of this region. Subcloning and nucleotide sequencing indicated that this positive regulator gene was virF. Product analysis of the virF gene with minicells showed that two peptides (30 and 21 kilodaltons) were synthesized and that at least the 30-kilodalton protein was essential for regulation of the ipa genes.  相似文献   
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