Time filter

Source Type

Truro, United Kingdom

Blake E.,Clinical Photobiology | Curnow A.,Clinical Photobiology
Photochemistry and Photobiology | Year: 2010

Photodynamic therapy (PDT) with the pro-drugs 5-aminolevulinic acid (ALA) or methyl aminolevulinate (MAL) utilizes the combined interaction of a photosensitizer, light and molecular oxygen to ablate tumor tissue. To potentially increase accumulation of the photosensitizer, protoporphyrin IX (PpIX), within tumor cells an iron chelator can be employed. This study analyzed the effects of ALA/MAL-induced PDT combined with the iron chelator 1, 2-diethyl-3-hydroxypyridin-4-one hydrochloride (CP94) on the accumulation of PpIX in human glioma cells in vitro. Cells were incubated for 0, 3 and 6 h with various concentrations of ALA/MAL with or without CP94 and the resulting accumulations of PpIX, which naturally fluoresces, were quantified prior to and following light irradiation. In addition, counts of viable cells were recorded. The use of CP94 in combination with ALA/MAL produced significant enhancements of PpIX fluorescence in human glioma cells. At the highest concentrations of each prodrug, CP94 enhanced PpIX fluorescence significantly at 3 h for ALA and by more than 50% at 6 h for MAL. Cells subsequently treated with ALA/MAL-induced PDT in combination with CP94 produced the greatest cytotoxicity. It is therefore concluded that with further study CP94 may be a useful adjuvant to photodiagnosis and/or PpIX-induced PDT treatment of glioma. © 2010 The Authors. Journal Compilation. The American Society of Photobiology. Source

Campbell S.M.,Clinical Photobiology | Tyrrell J.,Clinical Photobiology | Marshall R.,Clinical Photobiology | Curnow A.,Clinical Photobiology
Photodiagnosis and Photodynamic Therapy | Year: 2010

Background: Patients with localised scleroderma receiving aminolevulinic acid (ALA)/methyl aminolevulinic acid (MAL)-photodynamic therapy (PDT) were noted to show a reduction in skin tightness, suggesting that this therapy reduces skin sclerosis [1]. Karrer and colleagues treated patients with 5-ALA-PDT once or twice weekly for 3-6 months and in all patients the therapy was reported to be highly effective for sclerotic plaques.In view of the potential benefit of PDT in reducing skin sclerosis, the following study looks at the possible clinical and histological effects of topical PDT on the mechanism of scarring, looking particularly at hypertrophic scars. Methods: Patients with long standing hypertrophic scars were treated with MAL-PDT on two occasions at week apart, and repeated for 3 sessions at 6-weekly intervals. PDT effect was studied by means of fluorescence imaging throughout the treatment and biopsies were taken prior to and 6 weeks post-treatment to observe histological changes. Results and conclusions: Six weeks following the treatment the scarred areas had significantly softened and become more flexible clinically and histologically there had been a significant increase in elastin fibres.This suggests that ALA/MAL-PDT may be a useful treatment or adjuvant therapy in the treatment of scarring. © 2010 Elsevier B.V. Source

Discover hidden collaborations