Photophysical properties and in vitro photocytotoxicity of disodium salt 2.4-di(alpha-methoxyethyl)-deuteroporphyrin-IX (Dimegine).

Photophysical and in vitro photocytotoxicity studies were performed for the photosensitizer Dimegine, a disodium salt 2.4-di(alpha-methoxyethyl)-deuteroporphyrin-IX with very low systemic toxicity. The singlet oxygen and luminescence quantum yield were ΦΔ = 0,65 ± 0,06, and Φƒ=0,11 ± 0,01 respectively, and were independent of the excitation wavelength. The photobleaching coefficients for Dimegine dissolved in phosphate buffer (pH 7.4), and DMEM medium at concentration 2 µM/l and in phosphate buffer (pH 7.0) at concentration 10 µM/l were 16·10-5, 9·10-5 and 2·10-5 respectively. In vitro cellular distribution and photocytotoxicity was studied in two human (U87 - primary glioblastoma and HT1376 - bladder cancer) and two rat cell lines (RG2 - glioma, and AY27 - bladder carcinoma). Fluorescence microscopy analysis shows primary Dimegine accumulation as small fluorescent inclusion bodies around the nuclei, suggesting an apoptotic over a necrotic cell death mechanism. The PDT efficacy was slightly higher for the rat cell lines over the human-derived cell lines, with LD50 values of 2,5 µM/l, 2.8 µM/l, 4.5 µM/l, 2.8 µM/l using 530 nm excitation wavelength for AY27, RG2, HT1376 and U87 respectively, and 1.8 µM/l, 2 µM/l, 5 µM/l, 2.4 µM/l using 625 nm excitation wavelength for AY27, RG2, HT1376 and U87 respectively. Comparison to literature data showed that Dimegine demonstrated improved phototherapeutic characteristics comparing to PpIX-mediated PDT.

[Actual nutrition and biochemical parameters of the food status of workers exposed to chlorobenzene]. / Fakticheskoe pitanie i biokhimicheskie parametry pishchevogo statusa rabochikh, kontaktiruiushchikh s khlorbenzolom.

Workers of two chemical plants exposed to chlorobenzene were examined for actual nutrition and effects of the treatment and prophylactic diet on the food status. Investigation of the actual nutrition has demonstrated that the energy value of the daily diets approaches the magnitudes established for the given occupational and age group whereas the daily distribution of food with respect to the caloric value and alimentary substances does not correspond to the hygienic standards. The treatment and prophylactic diets developed for the workers were also characterized by disproportion between the dietary components. As compared to the control group, the workers exposed to chlorobenzene demonstrated a lower content of total glutathione in blood plasma. The majority of the workers manifested ascorbic acid deficiency. In accordance with the study of the coefficients of the activation of erythrocytic enzymes, it may be concluded that the workers placed on the treatment and prophylactic diet are better provided with vitamins B1, B2 and B6 than the workers of the housing and communal services. Thirty percent of the workers showed vitamin B6 deficiency. This may have an adverse action on the resistance to industrial substances conjugating with glutathione. The rate of vitamin B1 deficiency was also fairly high, whereas in the workers of one of the plants the magnitude of the TDP-effect appeared higher than normal.