## 2 Materials and Methods
### Device and Procedure for Activating the WP  
For a clinical study of the WP activation method and evaluation of its effectiveness, a specialized device for dosed exposure to LTP discharges excited by a current with a frequency of 6.78 MHz was developed. The block diagram of the device, consisting of 6 functional elements, is shown in Figure 1. The scheme of the plasma device almost completely repeats the scheme of construction of commercial plasma electrosurgical devices. The scheme of the plasma device used is described in more detail in [28]. A feature of the HF generator (1) is the ability to briefly deliver high power required to initiate LTP discharges on a needle electrode in the electrolyte component of the biological tissue. The voltage generation unit (2) ensures the generation of short high voltage pulses on a low-resistance load. The output power generation unit (3) has 8 power levels set within 1.0-15.0 W with the ability to change the duty cycle from 1.0 to 10.0. The duty cycle parameters, in turn, are the pulse duration and the number of pulses in a burst. The dosing unit (4) allows the operator to select one of five exposure values within 0.5-5.0 s. Activation elements (5) ensure the inclusion of HF current with the exposure parameters set by the operator using a floor pedal or an activation button on the electrode holder. The applicator (6) is a holder of replaceable needle electrodes, which were Mesoram RLMOS 30G needles for mesotherapy and microinjections, 3.0 and 6.0 mm long and 0.3 mm in diameter, which were inserted to the full length into predesignated zones (slightly altered skin around the DU, granulating areas in the bottom of the wound). An electrically conductive plate with an area of 120.0 cm\({}^{2}\) was used as a neutral electrode, or the role of a neutral electrode was performed by external elements of the patient's circuit at a frequency of 6.78 MHz due to their electrical capacitance to the ground. The WP activation procedure was carried out by chipping along the border of pathological areas of integumentary tissues according to the previously described method [31]. The needle electrode was inserted into the tissue and high-frequency voltage was applied to it. The high-frequency current causes the evaporation of the interstitial (intracellular) fluid around the needle electrode, which leads to the appearance of a gaseous shell, consisting mainly of water vapor. A low-temperature, highly nonequilibrium plasma is ignited in the gaseous envelope according to the mechanism used in plasma electrosurgery. Figure 1: Functional block diagram of the device for activation of reparative processes. The plasma parameters are practically the same as those of the plasma used in plasma electrosurgery [32]. The temperature of the plasma-forming gas is not higher than 100 \({}^{\circ}\)C. The criterion for the ignition and combustion of plasma inside the tissue is the characteristic current instability due to plasma instabilities. The impact was carried out with an exposure of 1.0-3.0 s and an installed power of 5.0 \(\pm\) 1.5 W. The exposure parameters were set by the level of the installed output power, the duty cycle, and the duration of the exposure. The range of parameter values made it possible to choose the current and voltage values that ensure the optimal process of generating plasma discharges according to the criterion of the minimum destructive effect of a thermal nature. Experimental data show that the dosing of the impact energy at a frequency of 6.78 MHz in the range of real loads can be carried out with an error of no more than 9%, which ensures a sufficiently high repeatability of the results. The frequency of the WP activation procedure was as follows: the initial WP activation session, then every 3-4 days in addition to the standard treatment (sanation with antiseptics, dressings with polyethylene oxide-based ointment, etc.).