Experiments were performed on five batches of Wistar inbred rats with Walker-256 carcinoma receiving sole (PDT, MAK) or combined therapy (PDT+MAK−A; PDT+MAK−B); the control batch (HBSS) consisted of animals with untreated tumors. The results were as follows: (a) the sole treatment (PDT, MAK) gave survival rates between 37.7 and 47.5 %, the "combined" therapy in five doses increased significantly (70.8 %) the survival rate of tumor bearing rats as well as the rate of complete regression (82.1%). The cell-mediated immunity test and histopathological and as well as the electron microscopy observation were in full agreement with the results above. Summing up, this results demonstrate that "combined" photodynamic therapy with intra and peritumoral MAK infusion stimulated cell - mediated antitumoral activity, increased survival rates and reduces incidence of Walker-256 carcinoma in rat model.
Phototherapy has been around in clinical practice for more than 5,000 years, but has not shown consistent clinical results or attracted continuous real attention until the last 5 decades, since just before the ‘birth’ of the laser. Although phototherapy can be construed to mean therapy delivered with any kind of light, including lasers, intense pulsed light (IPL) systems, various incandescent and arc lamps and most recently, light-emitting diodes (LEDs), a gradual consensus has formed that ‘phototherapy’ means the treatment of a disease or condition with the delivery of athermal and atraumatic levels of photon energy. This rules out IPL systems and laser systems specifically designed for so called nonablative skin rejuvenation, but does not however rule out surgical lasers used in a defocused mode so that the incident power density or irradiance is well below the photodestructive cellular survival threshold. Phototherapy with the new generation of quasimonochromatic LEDs with much greater and more stable output power compared with their earlier generations, is currently attracting a great deal of attention, and indeed controversy, in clinical practice for skin conditions such as acne, skin rejuvenation and wound healing. Pain attenuation has also been reported with a near infrared LED source. It has become evident from the literature that LED therapy works best when two or more wavelengths are combined in a sequential manner, not simultaneously, in a photobiologically appropriate manner for the target cells and tissues. Perhaps an even greater potential for LED therapy exists in its being incorporated into our conventional clinical practice as an adjunctive treatment to improve our already good results, particularly when the cost-effectiveness of these systems is considered. Some of the mechanisms by which this athermal and atraumatic light source can beneficially affect targeted tissues have already been elucidated, but much more work awaits before we can unlock the full scientific potential behind the good clinical results. There is no doubt that LED therapy has arrived, but its impact remains to be maximized.
The cascade system of biological integrity with an emphasis on low level laser therapy (LLLT) is poorly understood. A clinical study was made to assess pain attenuation with LLLT in connection with serum prostaglandin (PG)E2 levels. Seventy six women with periarthritis scapulohumeralis, mean age of 61.4 years, were exposed to a diode semiconductor laser unit with an output power of one watt and wavelength of 830 nm. Irradiation was administered for 3 minutes daily or on alternate days, for a total of 10 times. The therapy proved effective in 64 cases or 84.2%. There was no significant correlation between age and length of condition and the effectiveness of LLLT. The relevant pain-scoring system with a visual analog scale (VAS), 30.0±2.0 after irradiation in the clinically affected group, was significantly lower than 80.3±2.5 before irradiation in the same group and also lower than 64.2±6.3 after irradiation in the group unaffected by this therapy. In the affected group PGE2 levels were 5.4±0.3 after irradiation, which were significantly lower than 7.2±0.5 before irradiation. In the unaffected group, however, there was no significant difference between PGE2 levels before and after irradiation. Substantial change in PGE2 levels showed a significant difference by group. The result suggests that LLLT can often alleviate nociceptive pain associated with the decline of serum PGE2 levels.