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Mechanomagnetochemical activation can increase the concentration of paramagnetic centers (free radicals) in the anticancer drug, for example, doxorubicin that enables to influence its magnetic properties under external electromagnetic field and improve its magnetic sensitivity and antitumor activity. The principles of design and operation of mechanomagnetic reactor for implementation of this technology which includes mechanomagnetochemical activation and electromagnetic radiation of the drug are described in the paper. The methods of vibration magnetometry, electron paramagnetic resonance spectroscopy and high-performance liquid chromatography were used for studying of doxorubicin mechanomagnetic activation effects. The studies have shown that a generator of sinusoidal electromagnetic wave, working chambers from caprolactam, fluoroplastic or organic materials with metal inserts and working bodies made from steel or agate depending on the required doxorubicin magnetic properties are expedient to use in the designed mechanomagnic reactor. Under influence of mechanomagnetochemical activation doxorubicin, which is diamagnetic, acquires the properties of paramagnetic without changing g-factors in the spectra of electron paramagnetic resonance. Mechanomagnetochemical activation of doxorubicin satisfies pharmacopoeia condi tions according to the results of liquid chromatography that points on perspective of this method using in technology of tumor therapy with nanosized structures and external electromagnetic radiation.

Excess body weight has been causally linked to an increased risk of different cancer types, including gastric cancer but the mechanisms underlying this relationship are not well understood. Superoxide generation rate, activity of complex I in electron transport chain of mitochondria, activity of matrix metalloproteinase (MMP-2 and 9) of adipose tissues (AT) of patients with gastric cancer in AT located adjacent to tumor (ATAT) and at a distance of 3 cm (ATD) are measured to follow the connection of the redox state with some of the microenvironment indicators (HIF-1α, CD68, Plin5), body mass index (BMI) and cancer metastasis. Superoxide generation rate in ATAT positively correlates with BMI (r = 0.59, p < 0.05) being 4 times higher than in control (p < 0.05). MMP-2, 9 activities in ATAT positively correlate with BMI (r = 0.67, p < 0.05) being 3.3-4.0 higher than in control (p < 0.05). In ATD a statistically significant increase of MMP-2 activity is found. In ATAT for the group of patients with distant metastasis (M1) the superoxide generation rate, MMP-2, 9 activities are about 2 times higher (p < 0.05) than in the subgroup without distant metastases (M0). M1 is also characterized by the increased values of HIF-1α+ (factor 1.25), CD68+ (factor 1.4) and Plin5+ (factor 2.1) compared to M0 category in tumor tissues (p < 0.05). The results can be used for better understanding the mechanism(s) of symbiosis of tumor and adipose tissues as well as serve as a basis for new therapeutic approaches., (Copyright © 2019 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.)