• Journal of Photoscience
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• v.2 no.1
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• pp.37-45
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• 1995

INTRODUCTION : Psoralens are planar tricyclic furocoumarins present in numerous plants and fungi found throughout the world.' Naturally occurring and synthesized psoralen derivatives(see Figure 1) are photosensitizers of UVA especially from 320 nm to 400 nm, a range at which cellular nucleic acids and proteins are weakly absorbing if any at all. Because of their skinphotosensitizing properties, these compounds have been used in the photochemotherapy of psoriasis and vitiligo. However, undesirable side effects such as carcinoma development in hairless mice as well as possible liver damage from the use of 8-methoxypsoralen(8-MOP) have been reported. The other photobiological effects include inactivation of DNA viruses, killing and mutagenesis of bacteria, inhibition of tumor transmitting capacity of various cells, and hyperpigmentation on human and guinea pig skin. PUVA(psoralen+UVA) photochemotherapy is in fact thousands of years old, having been used in Egypt and India since B.C. 1200-2000. Photochemotherapy for a common disfiguring disease, vitiligo, was practiced in the ancient world by physicians and herbalists who used boiled extracts of the fruits of certain umbelliferous plants, e.g. Ammi majus Linnaeus in Egypt or the leguminous plants, Psoralea corylifolia L. in India. It was first described by Kuske in 19388 that photosensitization of skin by plants was related to the presence of psoralen. He identified natural psoralens in plants as photosensitizers and isolated bergapten(5methoxypsoralen) from the oil of bergamot. The scientific interest in photosensitizing psoralens, however, has grown considerably after the introduction into clinics of the psoralen photochemotherapy for the treatment of psoriasis and of other skin (abbreviation)

• Journal of Oral Medicine and Pain
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• v.25 no.2
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• pp.159-165
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• 2000

Subsequent to an allogenic stem cell transplantation(ASCT) on patients with hematologic malignancy(AML, ALL, CML, multiple myeloma, lymphoma etc.), chronic GVHD(graft versus host disease), which is an immunological reaction, occurs. With treatment results from patients who were diagnosed with ALL(acute lymphocytic leukemia), undergone BMT(bone marrow transplantation) and showed oral and skin lesions due to GVHD, treatment of oral manifestations of leukemia and its general management were studied. 90% of patients with chronic GVHD show change in the oral mucosa causing oral manifestations such as leukoplakia, lichenoid change of the oral mucosa, mucosal atrophy, erythema, ulceration and xerostomia. In treating GVHD, extensive systemic immunosuppression cause bacterial, viral, fungal infection that are fatal, and even if the treatment is successful, the patient is already in a severe immunosuppressed state. Therefore, localized target therapy is preferred. In another words, topical application(rinse, cream, ointment etc.) of cyclosporin and steroid in treating oral chronic GVHD is highly recommended, and the use of PUVA(Psoralen Ultraviolet A) and thalidomide is reported to be effective. In treating such diseases, dental treatment to control pain and prevent secondary infection of oral manifestations is very important. To those patients with systemic diseases who show limited effect by general dental treatment, non-invasive treatment such as the dental laser, in addition to the use of drugs, may be necessary to actively treat pain and help the healing process. For greater results, new effective methods are to be developed for treatment.