2021, Maklygina, Y., Romanishkin, I., Skobeltsin, A., Farrakhova, D., Loschenov, V., Лощенов, Виктор Борисович

© 2021 by the authors. Licensee MDPI, Basel, Switzerland.In this work, a new approach was tested to assess the cellular composition of tissues by time-resolved methods of fluorescence analysis of exogenous and endogenous fluorophores. First of all, the differences in fluorescence kinetics of endogenous fluorophores (coenzymes NADH and FAD) in tumour and immunocompetent cells were determined. After that, differences in fluorescence kinetics of photosensitizer 5 ALA-induced protoporphyrin IX were established due to its different metabolism in cells of different phenotypes. Kinetics of photoluminescence of NADH and FAD coenzymes as well as photosensitizer were studied by means of two different methods: time-resolved spectroscopy based on a streak-camera and fibre optic neuroscopy, which served to perform process monitoring and regular fluorescence diagnosis of the probed region. Time-resolved fluorescence microscopy (FLIM) was used as a control technique. Time-resolved spectroscopic fluorescence lifetime analysis was performed on sexually mature female rats induced with glioma C6 brain tumour under in vivo conditions; thus, under conditions where the immune system actively intervenes in the process of oncogenesis. In this regard, the aim of the study was to recognize the cellular composition of the brain tumour tissue, namely the ratio of cancer and immunocompetent cells and their mutual localization. Understanding the role of the immune system thus provides new ways and approaches for further diagnosis and therapy, making tumour-associated immune cells a prime target for modern therapies.

2022, Barmin, R. A., Maksimova, E. A., Rudakovskaya, P. G., Gayer, A. V., Shirshin, E. A., Petrov, K. S., Terentyeva, D. A., Gusliakova, O. I., Sindeeva, O. A., Klimenko, O. A., Chuprov-Netochin, R. N., Solovev, A. A., Huang, G., Ryabova, A. V., Loschenov, V. B., Gorin, D. A., Лощенов, Виктор Борисович

2024, Romanishkin, I. D., Ospanov A., Savelieva, T. A., Shugai, S. V., Loschenov, V. B., Савельева, Татьяна Александровна, Лощенов, Виктор Борисович, Оспанов, Ануар

2020, Makarov, V. I., Lukyanets, E. A., Kiselyova, S. K., Loschenov, V. B., Лощенов, Виктор Борисович

© 2020 IEEE.The use of crystalline nanoparticles of aluminium phthalocyanine (AlPc) as nanophotosensitizers for phototheranostic is a promising direction, but due to insufficient study of their properties depending on the method of production, size, ratio of solvent concentrations, the use of these compounds is not widely developed yet.The investigations of size dependence, absorption and fluorescence of AlPc nanoparticles on various particle production conditions were carried out, and optimal conditions for obtaining the most effective samples of initial solutions for their testing on cancer and immune cells were found.

2020, Maklygina, Y. S., Romanishkin, I. D., Savelieva, T. A., Loschenov, V. B., Савельева, Татьяна Александровна, Лощенов, Виктор Борисович

Gliomas are one of the most common brain tumors occurring in children and adults. Gliomas are primary, diffusely infiltrating brain tumors. There are few effective therapies for these type of cancer, and patients with malignant glioma fare poorly, even after aggressive surgery, chemo- and radiotherapy.

2025, Salmin, V. V., Loschenov, V. B., Ochirova A. B., Bainaev-Mangilev N. P., Салмин, Владимир Валерьевич, Лощенов, Виктор Борисович

2021, Proydakova, V. Y., Romanishkin, I. D., Kuznetsov, S. V., Lukyanets, E. A., Pominova, D. V., Bogatova, A. S., Akhlyustina, E. V., Saveleva, T. A., Loschenov, V. B., Поминова, Дарья Вячеславовна, Ахлюстина, Екатерина Витальевна, Савельева, Татьяна Александровна, Лощенов, Виктор Борисович

© 2021 Russian Photodynamic Association. All rights reserved.Today, photodynamic therapy is one of the most promising minimally invasive methods of treatment of various diseases, including cancer. The main limitation of this method is the insufficient penetration into the tissue of laser radiation used to activate photosensitizer molecules,which makes it difficult to carry out therapy in the treatment of large or deep-seated tumors. In this regard, there is a great interest in thedevelopment of new strategies for photodynamic therapy using infrared radiation for excitation, the wavelengths of which fall into the “transparencywindow” of biological tissues. In this work, it was proposed to use upconversion NaGdF4:Yb:Er nanoparticles (UCNP), which absorbinfrared excitation and serve as a donor that transfers energy to the photosensitizer. Photosens and phthalosens were chosen as the mostpromising photosensitizers for the study. The aim of this work was to study the energy transfer processes between upconversion nanoparticlesdoped with rare-earth ions and photosensitizer molecules. in order to excite photosensitizers with IR radiation and carry out photodynamictherapy of deep-seated neoplasms. Using spectroscopic and time-resolved methods, it has been demonstrated that there is an efficientenergy transfer between upconversion particles and photosensitizers phthalosens and photosens. The calculated efficiency of energy transferby the Foerster mechanism was 41% for the UCNP + photosens system and 69% for the UCNP + phthalosens system. It has been experimentallyand theoretically proved that there is a binding of photosensitizer molecules with UCNP by means of surfactants, leading to a reductionin the distance between them, due to which effective nonradiative energy transfer is realized. The generation of singlet oxygen by the phthalosensphotosensitizer upon excitation by means of energy transfer from UCNP, excited at 980 nm wavelength of, has been demonstrated.

2022, Kustov, D. M., Yakovlev, D. V., Moskalev, A. S., Kozlikina, E. I., Loshchenov, M. V., Kalyagina, N. A., Loschenov, V. B., Лощенов, Максим Викторович, Калягина, Нина Анатольевна, Лощенов, Виктор Борисович

Fluorescence visualization of pathologies is a popular form of endoscopic diagnostics in medicine. Interest in fluorescence optical visualization consists in providing information on the fluorescent signal spatial distribution by the photosensitizer fluorescence, which has a selective accumulation in tumor. Together with this, the determination of tissue saturation makes possible to assess the adequate of blood supply to anastomosis during surgical operation. © 2022 IEEE.

2021, Maklygina, Y., Romanishkin, I., Skobeltsin, A., Farrakhova, D., Loschenov, V., Лощенов, Виктор Борисович

© 2021 by the authors. Licensee MDPI, Basel, Switzerland.In this work, we tested a new approach to assess the presence of inflammatory process in the implant area using spectral methods and the technique of fiber fluorescence analysis of photosensitizers in nanoform. First of all, the spectral characteristics of the photosensitizer when interacting with the porous surface of the implant, based on hydroxyapatite under in vitro and in vivo conditions, were determined. Thus, it was shown that spectral characteristics of photosensitizers can be used for judgement on the process of inflammation in the implant area and thus on the local presence of the immunocompetent cells. The analysis was performed at a sufficient depth in the biotissue by using the near-infrared spectral region, as well as two different methods: fiber-based laser spectroscopy and fiber-optic neuroscopy, which served to monitor the process and regular fluorescence diagnosis of the studied area. Fluorescence spectroscopic analysis was performed on experimental animals in vivo, i.e., under conditions of active immune system intervention, as well as on cell cultures in vitro in order to judge the role of the immune system in the interaction with the implant in comparison. Thus, the aim of the study was to determine the relationship between the fluorescence signal of nanophotosensitizers in the near infrared spectral region and its parameters with the level of inflammation and the type of surface with which the photosensitizer interacts in the implant area. Thus, fiber-optic control opens up new approaches for further diagnosis and therapy in the implant area, making immune cells a prime target for advanced therapies.

2021, Meerovich, G., Romanishkin, I., Akhlyustina, E., Strakhovskaya, M., Kogan, E., Angelov, I., Loschenov, V., Borisova, E., Лощенов, Виктор Борисович

The result of photodynamic action significantly depends on the density of the light dose absorbed by the photosensitizer. The efficiency of using light to excite photosensitizer molecules and minimization of its loss plays an important role in ensuring the overall success of the process. When carrying out photodynamic treatment of thin sensitized layers (such as inactivation of surface pathogens or in vitro screening studies of photosensitizers), only a part of the light dose is absorbed in the layer, while a significant part is lost, especially at low concentrations of the photosensitizer. In this work, we evaluate the decrease in absorbed light dose depending on the extinction and concentration of the photosensitizer in a thin sensitized layer, the shape of its absorption spectrum, and the shape of the excitation light source spectrum. It was found out that a significant loss of the absorbed dose occurs upon excitation of photosensitizers, especially with low extinction, when using light sources with a broad emission spectrum. This loss must be taken into consideration when predicting the results of photodynamic exposure and optimizing its tactics. © 2021 Journal of Biomedical Photonics & Engineering. © J-BPE.