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The paper presents steady-state and time-resolved experiments on photophysical processes associated with photodynamic inactivation of infections provided by nebulization of Radachlorin photosensitizer solution. As models of surfaces subjected to photodynamic inactivation we used glass, plant leaf, mushroom cap peel and superficial fascia of chicken and salmon skin flaps. The oxygen content in the photosensitizer solution was varied by blowing with atmospheric air and with pure oxygen. It was shown that singlet oxygen was generated efficiently in the aerosol jet and that its amount increased noticeably at higher oxygen concentrations. The kinetics of photosensitizer photobleaching on different surfaces were found to be significantly different with characteristic decay times varying from seconds for leaf and glass to minutes for fascial flaps. This observation was attributed to much faster oxygen depletion on rough crumbly surfaces of biological samples due to effective oxidation reactions occurred. The singlet oxygen generation and degradation times, and the relative quantum yield were determined on different surfaces by recording time-resolved phosphorescence at about 1270 nm under normoxic and hyperoxic conditions and analyzed on the basis of the set of master equations. The results obtained provide reference marks for choosing optimal irradiation durations for photodynamic inactivation of pathogenic infectious agents (bacteria, mycobacteria, fungi, viruses) on mucous membranes, including the tracheobronchial tree., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The investigation of in-vitro response of cell cultures derived from tumor material of individual patients with similar tumor localizations to photodynamic treatment is presented. Tumor types included in the research were renal cell carcinoma, melanoma and alveolar, synovial, lypo- and osteo- sarcomas. Long-term observations of treatment-induced morphological changes in cells were performed by means of digital holographic microscopy. A substantial variance in response of cells of individual patients with similar tumor types and localizations to photodynamic treatment with the same dose has been observed. These peculiarities are indicative of the demand to personalized protocols of photodynamic treatment. The elevated resistance of cells of some patients to treatment at high doses highlights potential limitations of photodynamic therapy for some patients. Digital holographic microscopy is shown to be an informative label-free noninvasive tool allowing for long-term monitoring of cell samples in vitro and providing quantitative information on necrosis rate and loss of cellular dry mass. The developed methodology can be generalized for analysis of cellular response to various therapies., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Introduction: Recently, the COVID-19 pandemic has spread globally, necessitating the development of new methods for its prevention and treatment. The purpose of this study was to evaluate the antiviral activity of photodynamic therapy (PDT) against SARS-CoV-2 in vitro., Methods: Vero E6 cells and SARS-CoV-2 isolated in Russia were used for PDT with methylene blue (MB) and Radachlorin. A continuous laser with wavelength λ = 662 nm in doses of 16 J/cm 2 and 40 J/cm 2 laser irradiation was used for PDT of a viral suspension and SARS-CoV-2-infected cells. The direct cytopathogenic effect of SARS-CoV-2 was evaluated via light microscopy to calculate the TCID 50 in the samples and perform statistical analysis., Results: Viral suspensions of SARS-CoV-2 that had a TCID 50 greater than 10 3 were inactivated by PDT in the presence of MB and Radachlorin. Vero E6 cells were protected from 10 4 TCID 50 of SARS-CoV-2 by PDT post infection. The range of protective concentrations was 1.0-10.0 μg/ml and 0.5-5.0 μg/ml for MB and Radachlorin, respectively. Additionally, it was found that MB and Radachlorin also possess significant antiviral activity even without PDT. The 50 % inhibitory concentration (IC 50 ) against 10 2 TCID 50 of SARS-CoV-2 was found to be 0.22 and 0.33 μg/mL with the addition of MB and Radachlorin, respectively, to cells concomitantly with virus, whereas in the case of applying the photosensitizers at 3.5 h post infection, the IC 50 was 0.6 and 2.0 μg/mL for MB and Radachlorin, respectively., Conclusion: PDT shows high antiviral activity against SARS-CoV-2 when combined with MB and Radachlorin in vitro., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Bronchoplastic surgical operations by means of invaginated method on 1 semicircle in lung malignant tumors were performed in 124 patients. Of them 116 patients (93,5%) had primary and 8 patients (6,5%) metastatic tumors. There were 94 men (75,8%) and 30 women (24,2%). The average age of patients was 56,4. The lesion of the right lung was observed in 78 patients (62,9%), of the left one in 46 patients (37,1%). Bronchoplastic lobectomies were performed in 98 patients (79%), bilobectomies - 17 patients (13,7%), segmentectomy - 4 patients (3.3%), isolated resections of bronchi - 5 patients (4,0%). All operations were radical. In all cases of lung cancer there was carried out extended inpsilateral lymph node dissection. Complications of different severity were observed in 24 patients (19,4%): pneumonia (4,8%), atelectasis (0,8%), insufficiency of bronchial sutures (3.2%), granulation stenosis of the bronchial anastomosis (1,6 %), chylothorax (0,8%), recurrent nerve palsy (2,4%), heart rhythm disorders (2,4%). Postoperative lethality was 4.8%.

There are summarized the foreign and domestic references of recent years devoted to methodology and the efficiency of the use of intraluminal high-dose radiation brachytherapy in patients with lesions of the central bronchi and trachea caused by primary and metastatic malignant tumors. It is presented own experience of applying this method in 207 patients. It is showed that in some patients to ensure the delivery of the radiation source to the area of interest it is advisable to perform firstly endotraheobronhial surgery with recanalization of the lumen of the respiratory pathways. The best is the use of intraluminal brachytherapy with high dose radiation. Palliative intraluminal irradiation of inoperable patients allowed achieving a good immediate results (65-95%), a significant reduction of the main symptoms--hemoptoe (87-95%), dyspnea (75-90%), obstructive pneumonia phenomena (50-85%), and significantly increasing survival median from 1-3 to 9-14 months. Following performance of chemoradiotherapy permitted increasing the survival median up to 15-20 months. The number of complications of intraluminal high-dose radiation brachytherapy was small, usually--pulmonary hemorrhage (2-7%) more likely developing when using large fractions--more than 10 g for 1 session.

The study includes data on 54 patients with pleural malignant lesions (39 with metastatic pleural malignant tumors and 15 with pleural malignant mesothelioma) received treatment using a multimodal approach: maximum cytoreduction, intraoperative photodynamic therapy and hyperthermic chemoperfusion of pleural cavity. A control group of patients with malignant pleural mesothelioma consisted of 21 patients who had undergone only conservative treatment. It was found out that the use two-thoracotomy surgical approach had advantages over standard thoracotomy across IV intercostal space. The use of multimodal treatment was accompanied by relatively low (1.85%) postoperative mortality on the background of a relatively high number (79.6%) of postoperative complications, easily cured in the early postoperative period. The use of multimodal therapy in treatment for metastatic pleural malignant lesions was accompanied by a median of disease-free survival of 11 months and a median of overall survival of 23 months. The proposed multimodal treatment compared with conservative methods of therapy improved disease-free (12 months vs. 7.5 months) and overall (18.8 months vs. 10.2 months) survival. Thus the use of a multimodal approach in treatment for pleural malignant lesions is relatively safe but requires further study.

There are presented results of photodynamic therapy (PDT) for patients with chemo- and radioresistant intradermal metastases of breast cancer using the matrix light-emitting diodes apparatus. To all patients prior to irradiation there was performed fluorescence diagnostics to assess the accumulation of the photosensitizer of chlorine series and photobleaching during PDT. The size of the irradiation area was 400 sm, the total dose of irradiation was 250J/cm2. PDT was accompanied by mild pain, which was stopped by administration of non-narcotic analgesics. Complete regression of intradermal lesions was registered in 2 of 4 cases, partial response was observed in 1 patient and the progression of the process in 1 case.