The Experts below are selected from a list of 26226 Experts worldwide ranked by ideXlab platform
Jennifer E. Ryder - One of the best experts on this subject based on the ideXlab platform.
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Photodynamic Therapy and Topical Aminolevulinic Acid
American Journal of Clinical Dermatology, 2003Co-Authors: Aditya K Gupta, Jennifer E. RyderAbstract:Photodynamic therapy is a non-invasive technique used in the treatment of skin diseases which has various advantages, one being the ability to localize treatment to the area being treated, which is common among most photosensitizers. Aminolevulinic Acid is a prodrug that is metabolized intracellularly to form the photosensitizing molecule protoporphyrin IX (PpIX). When PpIX is activated by light, cytotoxic reactive oxygen species and free radicals are generated. This phototoxic effect may cause malignant and non-malignant hyperproliferative tissue to be destroyed, to decrease in size, and to eventually disappear. The application of topical Aminolevulinic Acid 20% followed by the use of a blue light photodynamic therapy illuminator is indicated in the US for the treatment of non-hyperkeratotic actinic keratoses of the face or scalp. There are data suggesting that Aminolevulinic Acid/photodynamic therapy may also be beneficial in acne vulgaris, verrucae, psoriasis, mycosis fungoides, and human papillomavirus. This treatment modality has also proven effective in the management of skin cancer such as, Bowen disease and basal cell carcinoma. Further experience in the use of photodynamic therapy will help define its utility in the management of actinic keratosis and other dermatoses.
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Photodynamic therapy and topical Aminolevulinic Acid: an overview.
American journal of clinical dermatology, 2003Co-Authors: Aditya K Gupta, Jennifer E. RyderAbstract:Photodynamic therapy is a non-invasive technique used in the treatment of skin diseases which has various advantages, one being the ability to localize treatment to the area being treated, which is common among most photosensitizers. Aminolevulinic Acid is a prodrug that is metabolized intracellularly to form the photosensitizing molecule protoporphyrin IX (PpIX). When PpIX is activated by light, cytotoxic reactive oxygen species and free radicals are generated. This phototoxic effect may cause malignant and non-malignant hyperproliferative tissue to be destroyed, to decrease in size, and to eventually disappear. The application of topical Aminolevulinic Acid 20% followed by the use of a blue light photodynamic therapy illuminator is indicated in the US for the treatment of non-hyperkeratotic actinic keratoses of the face or scalp. There are data suggesting that Aminolevulinic Acid/photodynamic therapy may also be beneficial in acne vulgaris, verrucae, psoriasis, mycosis fungoides, and human papillomavirus. This treatment modality has also proven effective in the management of skin cancer such as, Bowen disease and basal cell carcinoma. Further experience in the use of photodynamic therapy will help define its utility in the management of actinic keratosis and other dermatoses.
Aditya K Gupta - One of the best experts on this subject based on the ideXlab platform.
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Photodynamic Therapy and Topical Aminolevulinic Acid
American Journal of Clinical Dermatology, 2003Co-Authors: Aditya K Gupta, Jennifer E. RyderAbstract:Photodynamic therapy is a non-invasive technique used in the treatment of skin diseases which has various advantages, one being the ability to localize treatment to the area being treated, which is common among most photosensitizers. Aminolevulinic Acid is a prodrug that is metabolized intracellularly to form the photosensitizing molecule protoporphyrin IX (PpIX). When PpIX is activated by light, cytotoxic reactive oxygen species and free radicals are generated. This phototoxic effect may cause malignant and non-malignant hyperproliferative tissue to be destroyed, to decrease in size, and to eventually disappear. The application of topical Aminolevulinic Acid 20% followed by the use of a blue light photodynamic therapy illuminator is indicated in the US for the treatment of non-hyperkeratotic actinic keratoses of the face or scalp. There are data suggesting that Aminolevulinic Acid/photodynamic therapy may also be beneficial in acne vulgaris, verrucae, psoriasis, mycosis fungoides, and human papillomavirus. This treatment modality has also proven effective in the management of skin cancer such as, Bowen disease and basal cell carcinoma. Further experience in the use of photodynamic therapy will help define its utility in the management of actinic keratosis and other dermatoses.
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Photodynamic therapy and topical Aminolevulinic Acid: an overview.
American journal of clinical dermatology, 2003Co-Authors: Aditya K Gupta, Jennifer E. RyderAbstract:Photodynamic therapy is a non-invasive technique used in the treatment of skin diseases which has various advantages, one being the ability to localize treatment to the area being treated, which is common among most photosensitizers. Aminolevulinic Acid is a prodrug that is metabolized intracellularly to form the photosensitizing molecule protoporphyrin IX (PpIX). When PpIX is activated by light, cytotoxic reactive oxygen species and free radicals are generated. This phototoxic effect may cause malignant and non-malignant hyperproliferative tissue to be destroyed, to decrease in size, and to eventually disappear. The application of topical Aminolevulinic Acid 20% followed by the use of a blue light photodynamic therapy illuminator is indicated in the US for the treatment of non-hyperkeratotic actinic keratoses of the face or scalp. There are data suggesting that Aminolevulinic Acid/photodynamic therapy may also be beneficial in acne vulgaris, verrucae, psoriasis, mycosis fungoides, and human papillomavirus. This treatment modality has also proven effective in the management of skin cancer such as, Bowen disease and basal cell carcinoma. Further experience in the use of photodynamic therapy will help define its utility in the management of actinic keratosis and other dermatoses.
Yona Tadir - One of the best experts on this subject based on the ideXlab platform.
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Selective photosensitizer localization in the human endometrium after intrauterine application of 5-Aminolevulinic Acid
American journal of obstetrics and gynecology, 1996Co-Authors: Mathias K. Fehr, Pius Wyss, Bruce J. Tromberg, Tatiana B. Krasieva, Philip J. Disaia, Fritz Lin, Yona TadirAbstract:Abstract OBJECTIVE: Our purpose was twofold: to determine the distribution of the endogenous photosensitizer protoporphyrin IX in the uterus and to ascertain the time interval leading to maximal endometrial fluorescence after intrauterine instillation of 5-Aminolevulinic Acid. STUDY DESIGN: One milliliter of a 400 mg/ml 5-Aminolevulinic Acid - Hyskon solution was instilled into the uterine cavity of 27 women before hysterectomy. On frozen sections of uterine samples 5-Aminolevulinic Acid - induced fluorescence was measured with fluorescence microscopy. RESULTS: 5-Aminolevulinic Acid - induced fluorescence could first be detected in the superficial endometrial glands 75 minutes after drug injection. In the endometrial gland stumps fluorescence intensity peaked 4 to 8 hours after 5-Aminolevulinic Acid instillation and was >48 times higher than in the underlying myometrium. CONCLUSIONS: Fluorescence in the endometrial glands suggests that selective photodynamic destruction of the endometrium may be possible 4 to 8 hours after intrauterine 5-Aminolevulinic Acid instillation. (Am J Obstet Gynecol 1996;175:1253-9.)
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Photodynamic destruction of endometrial tissue with topical 5-Aminolevulinic Acid in rats and rabbits
American journal of obstetrics and gynecology, 1994Co-Authors: Pius Wyss, Bruce J. Tromberg, Tatiana B. Krasieva, M.t. Wyss, Michael J. Schell, Michael W. Berns, Yona TadirAbstract:Objective: The goal of this study was to determine the optimal parameters for photodynamic endometrial destruction with topically applied 5-Aminolevulinic Acid, a precursor for the endogenous synthesis of the fluorescent photosensitizer protoporphyrin IX. Study Design: 5-Aminolevulinic Acid pharmacokinetics were measured in rat and rabbit models by analyzing tissue frozen sections 3 to 12 hours after topical administration. Dose-response studies were conducted for 100 to 400 mg/ml 5-Aminolevulinic Acid. Photodynamic therapy was performed intraluminally, and tissue morphologic features were evaluated 3 and 7 days after treatment. Results: Peak fluorescence was observed 3 hours after topical administration. Glandular fluorescence significantly exceeded stromal and myometrial in all studies, particularly for 200 mg/ml 5-Aminolevulinic Acid. Histologic studies revealed persistent epithelial destruction with minimal regeneration. Conclusion: Topical 5-Aminolevulinic Acid photodynamic therapy can be used for highly effective, long-lasting destruction of endometrial epithelium. However, optical dosimetry can vary, particularly in the rabbit model, and this appears to have an impact on long-term reepithelialization.
Richard J. Lilford - One of the best experts on this subject based on the ideXlab platform.
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Photosensitization of the endometrium with topical 5-Aminolevulinic Acid
American journal of obstetrics and gynecology, 1995Co-Authors: Michael J. Gannon, Nicholas Johnson, David J.h. Roberts, J. Andrew Holroyd, David I. Vernon, Stanley B. Brown, Richard J. LilfordAbstract:Photosensitization of the endometrium was attempted in vitro and in vivo by intrauterine administration of 5-Aminolevulinic Acid, which is converted to the photosensitizer protoporphyrin IX. Protoporphyrin IX was found in both functional and basal layers of the endometrial glands at concentrations nine and 10 times higher than myometrium in in vitro and in vivo experiments, respectively. Selective endometrial photosensitization is possible with topical 5-Aminolevulinic Acid, but it might not be distributed sufficiently evenly for use as a sensitizing agent in photodynamic ablation.
Pius Wyss - One of the best experts on this subject based on the ideXlab platform.
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Selective photosensitizer localization in the human endometrium after intrauterine application of 5-Aminolevulinic Acid
American journal of obstetrics and gynecology, 1996Co-Authors: Mathias K. Fehr, Pius Wyss, Bruce J. Tromberg, Tatiana B. Krasieva, Philip J. Disaia, Fritz Lin, Yona TadirAbstract:Abstract OBJECTIVE: Our purpose was twofold: to determine the distribution of the endogenous photosensitizer protoporphyrin IX in the uterus and to ascertain the time interval leading to maximal endometrial fluorescence after intrauterine instillation of 5-Aminolevulinic Acid. STUDY DESIGN: One milliliter of a 400 mg/ml 5-Aminolevulinic Acid - Hyskon solution was instilled into the uterine cavity of 27 women before hysterectomy. On frozen sections of uterine samples 5-Aminolevulinic Acid - induced fluorescence was measured with fluorescence microscopy. RESULTS: 5-Aminolevulinic Acid - induced fluorescence could first be detected in the superficial endometrial glands 75 minutes after drug injection. In the endometrial gland stumps fluorescence intensity peaked 4 to 8 hours after 5-Aminolevulinic Acid instillation and was >48 times higher than in the underlying myometrium. CONCLUSIONS: Fluorescence in the endometrial glands suggests that selective photodynamic destruction of the endometrium may be possible 4 to 8 hours after intrauterine 5-Aminolevulinic Acid instillation. (Am J Obstet Gynecol 1996;175:1253-9.)
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Photodynamic destruction of endometrial tissue with topical 5-Aminolevulinic Acid in rats and rabbits
American journal of obstetrics and gynecology, 1994Co-Authors: Pius Wyss, Bruce J. Tromberg, Tatiana B. Krasieva, M.t. Wyss, Michael J. Schell, Michael W. Berns, Yona TadirAbstract:Objective: The goal of this study was to determine the optimal parameters for photodynamic endometrial destruction with topically applied 5-Aminolevulinic Acid, a precursor for the endogenous synthesis of the fluorescent photosensitizer protoporphyrin IX. Study Design: 5-Aminolevulinic Acid pharmacokinetics were measured in rat and rabbit models by analyzing tissue frozen sections 3 to 12 hours after topical administration. Dose-response studies were conducted for 100 to 400 mg/ml 5-Aminolevulinic Acid. Photodynamic therapy was performed intraluminally, and tissue morphologic features were evaluated 3 and 7 days after treatment. Results: Peak fluorescence was observed 3 hours after topical administration. Glandular fluorescence significantly exceeded stromal and myometrial in all studies, particularly for 200 mg/ml 5-Aminolevulinic Acid. Histologic studies revealed persistent epithelial destruction with minimal regeneration. Conclusion: Topical 5-Aminolevulinic Acid photodynamic therapy can be used for highly effective, long-lasting destruction of endometrial epithelium. However, optical dosimetry can vary, particularly in the rabbit model, and this appears to have an impact on long-term reepithelialization.