## 3 Results and Their Discussion  
As a result of our studies of the processing of physiological solution by the cold plasma of the piezodischarge, we obtained the following dependencies of the increase in concentrations of the long-lived reactive oxygen and nitrogen forms (NO2\({}^{-}\), NO3\({}^{-}\), and H2O2) on processing time (Figures 3-5). The concentration of nitrites increases in short of cold-plasma treatment times and at times of -90 s, it reaches saturation, which is caused by their oxidation into nitrates. The concentration of HOCI in the studied solutions weakly depends on the processing time and does not exceed 5 \(\upmu\)M.  
Figure 4: Dependence of oxygen peroxide concentration in the physiological solution on the processing time by direct piezodischarge. The distance between the piezotransformer and the solution surface was 0.5 mm. The temperature of the surrounding medium was \(20\pm 2\)\({}^{\circ}\)C, and the air humidity was 70 \(\pm\) 3%. In detail, the experimental conditions are described in the Section 2. Figure 3: The dependence of nitrite concentration in the physiological solution on the time of processing by direct piezodischarge. The distance between the piezotransformer and the solution surface was 0.5 mm. The temperature of the surrounding medium was \(20\pm 2\)\({}^{\circ}\)C, and the air humidity was 70 \(\pm\) 3%. In detail, the experimental conditions are described in the Section 2. Neutral pH decreases to 4.53 already after 30 s of treatment and then remains at this value (Figure 6). A nonlinear decrease in pH indicates that the production of new compounds in the solution improves its buffer properties. In the studied time range for the processing of the physiological solution by direct piezodischarge, the vitality of myeloblastosis cells decreased, at maximum, to 88% (Figure 7), which not a clinically significant result, and it did not exhibit direct correlation with the processing time. The vitality of mononuclear leucocytes decreased proportionally to the processing time to 63%, at processing time of 90 s.  
Figure 5: Dependence of nitrate concentration in the physiological solution on the time of processing by direct piezodischarge. The distance between the piezotransformer and the solution surface was 0.5 mm. The temperature of the surrounding medium was 20 \(\pm\) 2 \({}^{\circ}\)C, and the air humidity was 70 \(\pm\) 3%. In detail, the experimental conditions are described in the Section 2. Figure 6: Changes in the pH of the physiological saline after exposure to piezoelectric direct discharge of variable duration. An asterisk * indicates a statistically significant difference (\(p<0.05\)) from the control. Apoptosis was recorded as the unique type of cell death in this experiment. At the same time, the results of the MTT test, which estimates the physiological activity of the cells, did not show a dependable difference of all points from the control. To construct the dependence shown in Figure 7, we only used the data obtained by the trypan blue dye, which shows cell vitality directly. Figure 8 shows the level of damage to the DNA at different processing times by the direct peiozodischarge of the physiological solution added to the nutritional medium. The selectivity of DNA damage of mononuclear leucocytes and mieloblastosis cells is seen when the processing time is 30 s. The maximum level of DNA damage of the mononuclear leucocytes is 51% at processing time of 90 s, and the maximum damage of mieloblastosis cells is 76% at a processing time of 30 s.  
Figure 8: Dependence of the level of damage to the DNA cells on the time of processing by the direct piezodischarge of the physiological solution added to the nutritional medium. The cells were kept in the RPMI nutritional medium with the addition of 10% fetal bovine serum, amphotericin, and gentamycinin, in a thermostat with increased CO2 concentration (5%) at temperature of 37 \({}^{\circ}\)C. In detail, the experimental conditions are described in the Section 2.