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Observation and selective destruction of biological tissues, due to use of photochemical reaction sensitised with photosensitive dyes, are applied in modern method of tumor diagnosis and treatment as well as destruction of atheromatous plaques and restenosis prevention. This method, called photodynamic method (PDT), has been developed for recent 30 years in USA, Canada, Japan, and China and in majority of European countries. It has many advantages that distinguish it from among other currently used diagnostic and therapeutic methods. Both, the applied photosensitizers and photodynamic effect influence on active biological compounds present in an organism, mainly on enzymatic proteins, hormones, and particular elements of immunological system. The PDT method can be used not only for in situ tumor treatment but also for the treatment in metastasis state. It was thought previously that direct activity of cytotoxic radicals and singlet oxygen causes tissues necrosis. At present, additional investigations are performed on destruction mechanisms, i.e., occlusion of blood vessels and lymphatic vessels and PDT influence on immunological system revealing in cytokines release.
In Poland, the technology of new class of photosensitizer - diaminoacid derivatives of protoporphyrin PP(AA)2Arg2 as well as the basic half-product - hemis of very high purity has been developed and activities for their industrial production have been performed. In vitro investigations on quantum luminescence yield and singlet oxygen quantum yield of the obtained preparations were made. These compounds do not show toxic properties and they are neither mutagenic nor teratogenic. Three aminoacid protoporphyrine derivatives were chosen for industrial scale production, i.e., PP(Ala)2Arg2, PP(Ser)2Arg2, PP(Plu)2Arg2 that were efficient for the largest number of tumors investigated on cell lines. A preparation being the mixture of these derivatives is called Sensyphyrine. In the first stage of Sensyphyrine examinations in surgery, otolaryngology, and teracosurgery clinics over 100 patients were investigated.
During the years 1999-2001, the technologies of Polish photosensitizer and dermatological preparation have been developed. This photosensitizer - IX(PPIX) protoporphyrine is 5-aminoavulenic acid (ALA) of pharmaceutic purity (99.5%) and the final form of dermatological preparation is in form of a cream (FOTOACID). The obtained preparation and designed diagnostic systems and therapeutic sources enabled us to carry out initial investigations on animals and next clinical in 400 patients.
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