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The paper provides a review of domestic and foreign literature on photodynamic therapy, which is mainly used by oncologists in the treatment of adult patients and is little known to pediatric surgeons. The aim of this work is to describe the history of the formation, principles and mechanisms of photodynamic therapy, the main groups of photo sensitizers, areas of clinical application and prospects for wider use in pediatric surgery. Literature sources were searched in the databases in Russian eLibrary and English Medline and PubMed. The following keywords were specified for the search: photodynamic therapy, dysplasia, metaplasia, angiodysplasia, Barretts syndrome, children. 865 papers were found, of which 66 were fully consistent with the purpose of our study and were analyzed. The data presented in the review of the literature indicate the high efficiency of the method of photodynamic therapy in the treatment of a number of diseases, mostly in oncology. In addition, the work contains theoretical calculations and separate reports on the effectiveness of the method in the treatment of dysplasia of varying degrees in children. Taking into account the minimally invasiveness of the technique, the relative cheapness of photosensitizers and equipment for generating laser radiation, it is possible to create a basis for conducting research on the treatment of children with various dysplasias, epithelial metaplasia, and vascular malformations. Another promising direction is the development of technologies for the use of photodynamic methods for the treatment of severe forms of pyoinflammatory diseases in children. In childhood surgery, there are nosological forms of diseases where the method of photodynamic therapy has the prospect of effective use. Limitations on the scope of this article do not allow for a detailed analysis of the existing experience in the use of photodynamic therapy in children, which will need to be done in subsequent works.

The aim of the study is to develop a method for early diagnosis of intrauterine infection (IUI). A study of markers of inflammation in the venous blood of 60 pregnant women was conducted. The study was followed by a retrospective assessment of the outcomes of pregnancies and childbirth. Of these, 33 patients with a gestation period of more than 37 weeks (full-term pregnancy) and, accordingly, 27 patients from whom the blood sample was taken at a period of less than 37 weeks - patients with the threat of premature birth (PB). PB is the main factor contributing to the development of IUI. 27 patients were diagnosed with premature rupture of the membranes (PROM). Of these, 15 are with the threat of PB. 8 of them had a diagnosed IUI. In all cases of diagnosed PROM, including those with IUI, the concentration of nitrite and nontiolate nitroso compounds (NO2-+RNO) in the mother’s blood plasma was 2.3±1.2 µM, while normally it does not exceed 0.1 µM (p0.1). Since the concentration index (NO2-+RNO) increased in almost all cases of PREM, unlike all other clinical and biochemical indicators used in modern medicine, there is an obvious sense of its use for the current monitoring of the health of pregnant women. But it is still impossible to say unequivocally about the possibility of monitoring the fetal health by concentration (NO2-+RNO) in the mother’s blood.

The article presents an experimental evaluation of the use of double-exposure speckle photography with circular and annular apertures in experimental mechanics using the example of determining the modulus of elasticity in tension. The description of the process of registration of speckle photography and its subsequent processing is given. Based on the results of calculations of the finite element model of the sample, the areawhere the boundary conditions do not affect its tension is determined. A description is given of the procedure for processing speckle photographs to determine the modulus of elasticity and the error in its measurement with different apertures.

DNA repair (DNA damage) foci observed 24 h and later after irradiation are called “residual” in the literature. They are believed to be the repair sites for complex, potentially lethal DNA double strand breaks. However, the features of their post-radiation dose-dependent quantitative changes and their role in the processes of cell death and senescence are still insufficiently studied. For the first time in one work, a simultaneous study of the association of changes in the number of residual foci of key DNA damage response (DDR) proteins (γH2AX, pATM, 53BP1, p-p53), the proportion of caspase-3 positive, LC-3 II autophagic and SA-β-gal senescent cells was carried out 24–72 h after fibroblast irradiation with X-rays at doses of 1–10 Gy. It was shown that with an increase in time after irradiation from 24 h to 72 h, the number of residual foci and the proportion of caspase-3 positive cells decrease, while the proportion of senescent cells, on the contrary, increases. The highest number of autophagic cells was noted 48 h after irradiation. In general, the results obtained provide important information for understanding the dynamics of the development of a dose-dependent cellular response in populations of irradiated fibroblasts.

Introduction. Early malignant tumor detection programs have significantly increased the survival rate of breast cancer patients but the results of drug therapy for this pathology are not always highly effective. Recently discovered iron-dependent cell death, ferroptosis, makes it a promising therapeutic target to reduce the recurrence rates.Objective – to study the induction of ferroptosis in breast cancer cells MCF-7 by quinazoline derivatives synthesized at the Research Institute of Experimental Diagnostics and Therapy of Tumors of the N.N. Blokhin National Medical Research Center of Oncology, Ministry of Health of Russia and to evaluate its antitumor activity on transplanted breast carcinoma Ca-755.Materials and methods. Derivatives of 3-hydroxyquinazoline were obtained by chemical synthesis and have a purity of at least 95 %. In this study 2D cultivation of MCF7 cells, phase-contrast and fluorescence microscopy, and a model of experimental growth of breast carcinoma Ca-755 in female hybrids of immunocompetent mice F1 (C57Bl/6 × DBA/2) were used.Results. Five derivatives of 3-hydroxyquinazoline, analogues of erastine, were studied in this work. The ferroptotic cell death was identified by the level of lipid peroxidation at the concentrations of 1/3 and 1/5 IC50. The level of lipid peroxidation induced by compound 3 was comparable with the activity of erastin in MCF7 cells at both 1/3 and 1/5 of IC50, the activity of the other four quinazoline derivatives was 50–70 % of the activity of erastin. In in vivo experiments at a dose of 30 mg/kg the antitumor efficacy of the compound 3 was higher than that of erastin at the same dose.Conclusion. The data obtained suggest that quinazoline derivative 3 might be considered as a promissisng antitumor agent to treat breast cancer.

The article summarizes the results of the plenary session of the international network conference “Regional development: new challenges for engineering education – SYNERGY-2021”, held at Kazan National Research Technological University from October 19 to 20, 2021. The forum which brought together representatives of universities and industrial enterprises of Russia and abroad was devoted to the issue of training engineers for the petrochemical industry. Among the participants were representatives of international societies for engineering education, ten national research universities and seven supporting universities of PJSC Gazprom, state authorities and industrial enterprises of Tatarstan. It was possible to observe the work of the plenary session in real time via the Internet in all the supporting universities of Gazprom. The event was organized by the Ministry of Science and Higher Education of the Russian Federation, the International Society for Engineering Pedagogy (IGIP), the Association of Engineering Education of Russia (AIOR), as well as the Ministry of Industry and Trade of the Republic of Tatarstan and Kazan National Research Technological University. Gazprom PJSC became the general sponsor. In total, the conference gathered more than 450 participants (380 online and 85 in person) from 40 universities in Russia, the USA, Great Britain, Germany, Portugal, Finland, Poland, Kazakhstan, Belarus, Armenia, Latvia, and Estonia. Representatives of 7 industrial enterprises spoke, 77 reports were made.

The overall effect of senescence on cancer progression and cancer cell resistance to X-ray radiation (IR) is still not fully understood and remains controversial. How to induce tumor cell senescence and which senescent cell characteristics will ensure the safest therapeutic strategy for cancer treatment are under extensive investigation. While the evidence for passage number-related effects on malignant primary cells or cell lines is compelling, much less is known about how the changes affect safety and Senescence-Associated Secretory Phenotype (SASP), both of which are needed for the senescence cell-based vaccine to be effective against cancer. The present study aimed to investigate the effects of repeated passaging on the biological (self-renewal capacity and radioresistance) and functional (senescence) characteristics of the different populations of short- and long-term passaging glioblastoma multiforme (GBM) cells responding to senescence-inducing DNA-damaging IR stress. For this purpose, we compared radiobiological effects of X-ray exposure on two isogenic human U87 cell lines: U87L, minimally cultured cells (3 years of continuous culturing after obtaining from the ATCC). U87L cells displayed IR dose-related changes in the signs of IR stress-induced premature senescence. These included an increase in the proportion of senescence-associated β-galactosidase (SA-β-Gal)-positive cells, and concomitant decrease in the proportion of Ki67-positive cells and metabolically active cells. However, reproductive survival of irradiated short-term cultured U87L cells was higher compared to long-term cultured U87H cells, as the clonogenic activity results demonstrated. In contrast, the irradiated long-term cultured U87H cells possessed dose-related increases in the proportion of multinucleated giant cancer cells (MGCCs), while demonstrating higher radiosensitivity (lower self-renewal) and a significantly reduced fraction of DNA-replicating cells compared to short-term cultured U87L cells. Conditioned culture medium from U87H cells induced a significant rise of SA-β-Gal staining in U87L cells in a paracrine manner suggesting inherent SASP. Our data suggested that low-dose irradiated long-term cultured GBM cells might be a safer candidate for a recently proposed senescence cell-based vaccine against cancer.

We performed a comparative study of the colony-forming ability and the number of residual foci of DNA repair proteins in cultured human lung fibroblasts (MRC-5 cell line) after exposure to subpicosecond beams of accelerated electrons with an energy of 3.6 MeV and quasi-continuous radiation (accelerated electrons with an energy of 4 MeV and X-rays). The yield of damages causing reproductive cell death after pulsed subpicosecond radiation exposure was higher by ~1.8 times than after quasi-continuous radiation exposure. The quantitative yield of residual γH2AX foci (phosphorylated H2AX histone, a protein marker of DNA double breaks) in cells irradiated with subpicosecond beams of accelerated electrons was shown to be ~2.0- 2.5-fold higher than in cells irradiated with quasi-continuous beams of accelerated electrons.

In a relatively isolated system of avian embryo, the metabolism of NO, a component of the dinitrosyl iron complexes (DNIC), the main NO donor in most tissues, depends on the ligands that make up the complex. This fact corroborates the earlier hypothesis that these ligands perform a regulatory function in NO metabolism. It is also shown that nitrite injected into the embryo is not oxidized to nitrate like NO in DNIC, but is accumulated outside the amniotic sac. Normally, nitrite is present in an embryo in trace amounts. These facts suggest that NO in the embryo is transferred from the donor molecule to a target in the embryo tissues further transformed with minimum oxidation to nitrite.

A convenient pathway to a new series of α-CF

An efficient way to access highly functionalized proline derivatives was developed based on a Cu(I)-catalyzed reaction between CF3-substituted allenynes and tosylazide, which involved a cascade of [3 + 2]-cycloaddition/ketenimine and a rearrangement/Alder-ene cyclization to afford the new proline framework with a high diastereoselectivity.