Larisa Mikhailovna Sosedova

Introduction. The prospect of using gadolinium nanoparticles to achieve high-contrast images when performing MRI with a significantly lower amount of the injected substance dictates the need for its comprehensive study. The high efficiency of nanoparticles can be achieved only due to an effective nanostabilizing matrix, a high–molecular compound of arabinogalactan isolated from Siberian larch wood. Materials and methods. Gadolinium nanocomposite encapsulated in a natural polymer matrix of arabinogalactan was administered per os for 10 days to adult mature male white rats (seventy two individuals) at a dose of 500 µg/kg body weight and 5000 µg/kg body weight, respectively. The examination took place in 2 stages – immediately after the end of the seed (early period) and 6 months after the end of exposure (remote period). A set of methods was used to assess the structural and functional state of the kidneys and liver, as well as determine the concentration of gadolinium in the above-mentioned organs.Results. The structural and functional features of the gadolinium nanocomposite effect on kidney tissue were expressed in a change in the area of the Shumlyansky–Bowman capsule, both in the early and in the long-term post-exposure period, however, these changes fit into the parameters of the physiological norm for this organ, while it was proved that the nanocomposite is able to penetrate into the liver and kidney tissue, remaining there in the remote post-contact period.Limitations. The use of one type of animal, a limited number of techniques used.Conclusion. The gadolinium nanoparticles, due to their specified physico-chemical characteristics and the almost complete absence of toxicity to target organs (kidneys, liver), are promising therapeutic and diagnostic drugs, which can later be used to create new-generation diagnostic drugs.Compliance with ethical standards. The work was carried out in accordance with the protocol of experimental research, the principles set out in the European Convention for the Protection of Vertebrate Animals Used for Experiments or Other Scientific Purposes ETS No. 123, GOST 33215–2014 “Guidelines for the care and care of laboratory animals. Rules of equipment of premises and organization of procedures”, Recommendations for euthanasia of experimental animals: Part 1, Part 2. Permission was obtained from the Local Ethics Committee to conduct research (Protocol No. 8 dated 12/15/2023).Contribution: Novikov M.A. – concept and design of research, data processing, editing, writing; Titov E.A. – concept and design of research editing; Pankova A.A. – collection of material and data processing; Lisetskaya L.G. – sample preparation of materials for concentration determination, recalculation of primary quantitative data; Sosedova L.M. – concept and research design, editing, and writing. All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.Using AI. To search for additional sources of literature, DeepSeek V4 artificial intelligence-based software was used (date of use – 03/19/2026).Conflict of interest. The authors declare no conflict of interest.Funding. The study was carried out within the framework of the state assignment of the East Siberian Institute of Medical and Environmental Research.Received: April 13, 2026 / Accepted: July 1, 2026 / Published: October 20, 2026

Introduction. Exposure to peat smoke is a significant environmental risk factor for public health. The period of puberty is characterized by increased vulnerability of the central nervous and reproductive systems to the toxic components of smoke, such as particulate matter (PM2.5) and carbon monoxide (CO). The aim of this study was to evaluate the remote effects of exposure to peat smoke on the central nervous system and reproductive system in white rats under conditions simulating real-world concentrations of PM2.5 and CO.Materials and Methods. Exposure to peat smoke was performed once for 4 hours during the pubertal period in white rats of both sexes. The mean concentrations of CO and PM2.5 in the exposure chambers were 29.3 ± 11.1 mg/m³ and 0.39 ± 0.61 mg/m³, respectively. Examination at adulthood included analysis of behavioral responses in the open field test, electroencephalography (EEG) recording, analysis of DNA fragmentation in blood cells, and histological analysis of brain tissue and testes.Results. A decrease in locomotor and exploratory activity was observed in exposed animals of both sexes. EEG changes were observed only in female white rats and were characterized by a statistically significant decrease in the mean amplitude of the β2 rhythm and an increase in the δ rhythm index compared with the control group. DNA damage in blood cells of exposed animals showed no statistically significant differences when compared with the control. Histological examination of the sensorimotor cortex of the brain and the testes revealed no abnormalities.Limitations. This study is limited to investigating the remote effect of a single exposure to peat smoke during puberty on the central nervous system and reproductive system of white rats.Conclusion. Exposure to peat smoke during puberty potentially contributes to the development of depressive-like behavior in adult white rats while preserving normal histological architecture of brain tissue. No gonadotoxic or genotoxic effects were observed.Compliance with ethical standards. the study was approved by the Local Ethics Committee (LEC) of the East Siberian Institute of Medical and Environmental Research (Protocol of the LEC of the East-Siberian Institute of Medical and Ecological Research No. 7 of 12/15/2023), conducted in accordance with the European Convention for the Protection of Vertebrates Used for Experiments or Other Scientific Purposes (ETS N 123), directive of the European Parliament and the Council Of the European Union 2010/63/EC of 09/22/2010 on the protection of animals used for scientific purposes.Contribution: Vokina V.A. – concept and design of the study, conducting the experiment, processing, analyzing and interpreting data, reviewing publications on the topic of the article; writing and design of the article; Sosedova L.M. – research methodology, writing and formatting of the article, checking of critical content; Pankova A.A. – conducting the experiment, collecting and initially processing the material, statistical processing of data; Abramova V.A. – collecting and pre-processing the material, statistical processing of data, preparing illustrations; Titov E.A. – collecting and pre-processing the material, statistical processing of data, preparing illustrations; Novikov M.A. – collecting and pre-processing the material, statistical processing of data, preparing illustrations. All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.Conflict of interest. The authors declare no conflict of interest.Funding. The work was carried out according to the research plan within the framework of the state task.Received: April 13, 2026 / Revised: June 2, 2026 / Accepted: July 1, 2026 / Published: October 20, 2026

Introduction. Wildfire smoke (WFS) is a complex mixture of particulate matter (PM) and toxic gases. Nevertheless, the contribution of each fraction to the overall toxicity remains poorly understood. Peat smoke, characterized by prolonged smoldering and a specific chemical composition, is of particular interest.Materials and methods. Peat smoke extracts (PSE) were obtained by bubbling smoke through a DMEM culture medium, followed by separation into unfiltered (UF-PSE), containing PM and soluble gas components, and filtered (F-PSE), containing only water-soluble gases. The obtained extracts in dilutions of 1:3, 1:1, 3:1 and without dilution were used for exposure of 3T3-SV40 mouse fibroblast culture. Cytotoxicity was assessed using the dye exclusion method, cellular metabolic activity was assessed using the MTT assay, and fragmentation and whole-genome DNA methylation were assessed using the comet assay. The qualitative composition of volatile compounds in UF-PSE was determined using gas chromatography-mass spectrometry.Results. No statistically significant differences in cell viability, fragmentation, or whole-genome DNA methylation were detected between the experimental and control groups. However, a trend toward a dose-dependent decrease in viability and metabolic activity was noted under UF-PSE, which was absent for F-PSE. The level of whole-genome DNA methylation under UF-PSE exposure was 1.6 times higher than under F-PSE. Volatile aldehydes C1–C4, primarily acetaldehyde and formaldehyde, were identified in the chemical composition of UF-PSE. No other volatile organic compounds were detected.Limitations. The study is limited to the use of a single 24-hour exposure to F-PSE and UF-PSE on 3T3-SV40 with a qualitative chemical analysis of smoke components, a study of its cytotoxicity, genotoxicity, ability to introduce epigenetic changes and influence the metabolic activity of cells.Conclusion. Although there were no statistically significant differences, the identified trends indicate a possible contribution of PM to the cytotoxicity and epigenetic effects of peat smoke, which requires further study, including chronic exposure and its quantitative chemical analysis.Compliance with ethical standards. The study was approved by the local ethics committee of the East-Siberian Institute of Medical and Ecological Research (Protocol No.7 of 12/15/2023), conducted in accordance with the European Convention for the Protection of Vertebrate Animals Used for Experiments or for Other Scientific Purposes (ETS N 123), Directive 2010/63/EC of the European Parliament and the Council of 22.09.2010 on the protection of animals used for scientific purposes.Contribution: Abramova V.A. – concept and design of research, data collection and processing, statistical data processing, text writing, editing; Vasyuhina P.O. – data collection and processing; Alekseenko A.N. – concept and design of research, data collection and processing; Vokina V.A. – concept and design of research, data collection and processing; Sosedova L.M. – concept and design of research, editing. All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.Conflict of interest. The authors declare no conflict of interest.Funding. The study had no sponsorship.Received: April 8, 2026 / Accepted: June 18, 2026 / Published: September 28, 2026

Introduction. The occupational safety system of firefighters involved in extinguishing forest fires focuses on injuries, burns, and acute intoxication, while the effect of smoke from forest fires on offspring and their development remains poorly understood. The development of methods for identifying biomarkers capable of predicting an unfavorable outcome for offspring is an important task of preventive medicine and occupational pathology.The study aims to evaluate the effect of peat fire smoke on the postnatal development of the offspring of exposed males.Materials and methods. The authors carried out the inhalation effect of peat smoke on male rats in inhalation chambers for 4 hours for five days. The CO content was 21(13;28) mg/m³, PM2.5 — 0.09(0.04;0.19) mg/m³. After mating with intact females, offspring were obtained in which survival, physical development, and sensorimotor parameters in the early postnatal period were studied.Results. The inhalation effect of peat smoke on male rats had no negative effect on their ability to reproduce. The mortality rate of offspring by the 21st day of life in the experimental group exceeded the level in the control group. In rat pups whose fathers were exposed to peat smoke, there was a delay in the timing of eruption of the lower incisors, eye opening, later maturation of sensory-motor reflexes and a decrease in locomotor activity. In general, the work substantiates the patterns of formation of long-term consequences of exposure to smoke from landscape fires, manifested by a decrease in survival, impaired development of sensory motor skills and the neurobiology of offspring behavior.Limitations. The study was performed on a rodent model (Wistar rats), which may limit the extrapolation of the results to other species and to humans. The study is limited to the study of physical development and sensorimotor reflexes in rats in the early postnatal period, born to mature adult males exposed to peat smoke, and does not take into account possible long-term effects. In this work, the coefficients of physical and harmonious development of offspring were not used and will be included in subsequent studies focused on a more detailed quantitative assessment of reproductive toxicity. It should also be considered that direct correlations with the human population require validation in clinical and epidemiological studies.Conclusions. Based on the revealed patterns, the researchers developed criteria for detecting the reproductive toxicity of smoke from landscape fires: increased mortality; impaired physical development (weight gain, late eruption of incisors); delayed maturation of sensorimotor reflexes; decreased muscle strength; decreased motor activity and increased stress levels. Broadcasting the results of the experimental study will make it possible to assess the risk of developmental disorders in young children among fire extinguishers. The consequences of postnatal disorders can be permanently fixed in ontogenesis and persist until puberty, burdening the process of learning and social integration and contributing to the development of increased anxiety and depression.Ethics. The study was conducted in accordance with the European Convention for the Protection of Vertebrate Animals Used for Experiments or Other Scientific Purposes (ETS No. 123), Directive 2010/63/EC of the European Parliament and of the Council of the European Union of 22.09.2010 on the protection of animals used for scientific purposes. The study was approved by the local Ethics Committee of the East-Siberian Institute of Medical and Ecological Research (Protocol No. 7 dated December 15, 2023).Contributions:Sosedova L.M. — research concept and design, literature review on the topic of the article, data analysis and interpretation, text writing, editing;Vokina V.E. — research concept and design, experiment, statistical data processing, data analysis and interpretation, literature review on the topic of the article;Pankova A.A. — conducting an experiment, collecting and primary processing of material, statistical data processing.Funding. The work was carried out according to the research plan within the Framework of the state assignment.Conflict of interest. The authors declare no conflict of interest.Received: 08.07.2026 / Accepted: 23.07.2026 / Published: 11.08.2026

Background . Restrictions on the use of gadolinium-containing radiocontrast agents due to the risk of acute and long-term complications drive the search for new, safer, and more effective gadolinium-based nanoparticle formulations. Aim . Comparative assessment of the magnetocontrast properties of a gadolinium nanocomposite and a gadolinium-based contrast agent. Methods. The dynamics of organ accumulation and visual MRI patterns were studied in 5 healthy female Wistar rats using a Siemens Avanto device with a magnetic field of 1.5 T. Anesthetized animals were placed in a ventral position within the head coil, after which a preliminary MRI scan was performed. A gadolinium nanocomposite solution and a reference agent (Omniscan®) were injected at equivalent gadolinium doses into the lateral tail vein or into the abdominal cavity, followed by repeat MRI scans with image acquisition every 2–3 minutes. The primary imaging areas were the abdominal cavity and retroperitoneal space, including the thoracic cavity. Results . Comparative analysis showed that gadolinium nanoparticles stabilized with arabinogalactan exhibit magnetocontrast properties, as evidenced by T1-weighted image enhancement of the liver parenchyma after intravenous administration and of the abdominal cavity after intraperitoneal administration. The magnetocontrast image of the kidneys and bladder was higher after Omniscan® administration than after gadolinium nanocomposite administration. However, the maximum contrast coefficient of the gadolinium nanocomposite in the liver parenchyma increased by 20 % compared to baseline. Omniscan® administration resulted in a 13 % increase in T1-weighted image intensity of the liver parenchyma.

Introduction. Exposure to smoke from natural peat fires during the early postnatal period leads to the development of a wide range of pathological conditions, among which the long-term effects of smoke on the central nervous system (CNS) remain the least studied.Materials and methods. Inhalation exposure of newborn rats to peat smoke was carried out during critical periods of ontogenesis – from the 23rd to the 27th day of life. The CO concentration in the inhalation chambers was 21 (13; 28) mg/m³, and the PM2.5 concentration was 0.09 (0.04; 0.19) mg/m³. At 3 months of age, the functional state of the CNS was assessed in the rats. The examination included open field behavioral testing, EEG recording, and histological examination of the cerebral cortex.Results. Males exhibited a sharp reduction in time spent in the center of the arena and a decrease in the exploratory area, indicating suppression of the active-searching component of behavior. EEG results in males showed a decrease in EEG amplitude characteristics, primarily due to waves in the low-frequency range (delta and theta rhythms). In females, conversely, an increase in amplitude and index was observed, largely due to fast-wave beta rhythm activity. No changes in nervous tissue structure were detected.Limitations. This study is limited to adult sexually mature white rats exposed to peat smoke from 23rd to 27th postnatal day.Conclusion. Exposure to peat smoke in the early postnatal period leads to impairments in species-specific behavior and the amplitude-frequency properties of the total bioelectrical activity of the cerebral cortex in adult sexually mature rats. The most significant shifts in CNS impairment are observed in male white rats.Compliance with ethical standards. The study was approved by the Local Ethics Committee of the East-Siberian Institute of Medical and Ecological Research (Protocol No. 32 dated 01/10/2023) and was conducted in accordance with the European Convention for the Protection of Vertebrate Animals used for Experimental and Other Scientific Purposes (ETS No. 123) and Directive 2010/63/EU of the European Parliament and of the Council of the European Union of September 22, 2010 on the protection of animals used for scientific purposes.Contributions: Sosedova L.M. – study concept and design, literature review, manuscript writing; Vokina V.A. – study concept and design, experiment conduction, data processing, analysis and interpretation, literature review, manuscript writing; Pankova A.A. – experiment conduction, data collection and primary processing, statistical analysis; Titov E.A. – histological specimen preparation and processing, data processing, statistical analysis; Novikov M.A. – histological specimen preparation and processing, data processing, statistical analysis; Savchenkov M.F. – editing, approval of the final version of the manuscript, responsibility for the integrity of all parts of the manuscript. Conflict of interest. The authors declare no conflict of interest.Funding. The study had no sponsorship.Received: March 24, 2026 / Revised: May 18, 2026 / Accepted: June 18, 2026 / Published: July 31, 2026

Introduction. Improving the accuracy, effectiveness, and safety of magnetic contrast media for MRI diagnostics is an urgent task for both clinical medicine and researcher. Therefore, the introduction of new innovative drugs opens up additional opportunities for assessing the functional state of organs and tissues, significantly increasing the accuracy of diagnosis and the effectiveness of treatment.Materials and methods. The parameters of acute toxicity, species and sexual sensitivity to an innovative drug containing gadolinium nanoparticles stabilized with arabinogalactane (GD-AH) and a commercial drug for MRI studies, Gadodiamide (a reference drug), were evaluated using the intragastric route of administration in outbred rats of both sexes at a dose of 2000 mg/kg body weight (b.w.). Additionally, acute toxicity assessment for the innovative drug GD-AG was performed with intraperitoneal administration in mice at doses of 2000 and 300 mg/kg b.w.Results. Intragastric administration of Gadodiamide and the innovative Gd-AG nanocomposite to rats of both sexes caused neither the death of animals nor changes in internal organs during macroscopic examination. Intraperitoneal administration of 2000 mg/kg b.w. GD-AG to mice resulted in 100% death. A dose of 300 mg/kg b.w. did not cause death, but macroscopic changes in internal organs were observed.Limitations. The study is limited to studying the acute toxicity parameters of an innovative drug containing gadolinium nanoparticles stabilized with arabinogalactane (GD-AG) and a commercial drug for MRI studies, Gadodiamide.Conclusion. According to the toxicometric parameters of acute toxicity, the average lethal doses for intragastric administration of the commercial drug Gadodiamide and the innovative nanocomposite Gd-AG to rats do not differ from each other and are definted as >2000 mg/kg b.w., which characterizes them as substances with a low risk of acute toxicity (hazard class V). The average lethal dose for the intraperitoneal route of administration of Gd-AG nanocomposite is in the range of 300 mg/kg b.w. < LD50 < 2000 mg/kg b.w., which belongs to the IV class of acute toxicity according to the classification of K.K.Sidorov and is defined as a substance with low toxicity.Compliance with ethical standards. The study was approved by the local Ethics Committee of the FSBSI VSIMEI (Protocol No. 8 dated 12/15/2023), conducted in accordance with the European Convention for the Protection of Vertebrate Animals Used for Experiments or Other Scientific Purposes (ETS N 123), Directive of the European Parliament and of the Council of the European Union 2010/63/EC dated 09/22/2010 on the protection of animals used for scientific purposes.Contribution: Sosedova L.M. – research concept and design, statistical data processing, text writing, editing; Novikov M.A. – data collection and processing, statistical data processing, text writing; Titov E.A. – literary study, data collection and processing, statistical data processing; Pankova A.A. – data collection and processing, statistical data processing; Vokina V.A. – data collection and processing, statistical data processing, text writing; Konkova T.V. – data collection and processing, synthesis of nanocomposite, statistical data processing; Sukhov B.G. – research concept and design, editing. All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.Conflict of interest. The authors declare no conflict of interest.Funding. The study had no sponsorship.Received: July 8, 2025 / Accepted: October 15, 2025 / Published: April 17, 2026

We studied the effect of peat smoke intoxication in pregnant rats on the early postnatal development of the second-generation offspring. The smoke was inhaled on days 14-18 of pregnancy. The first-generation offspring at puberty (3 months) was mated to produce the second-generation offspring in the following 3 variants: females exposed to prenatal smoke and intact males (experiment 1), males exposed to prenatal smoke and intact females (experiment 2), and males and females exposed to prenatal smoke (experiment 3); intact females and males comprised the control group. In the second-generation offspring, physical development, body weight gain dynamics, rate of maturation of sensorimotor reflexes, and parameters of open-field behavior were assessed. The results showed that exposure to peat smoke in pregnant rats reduced survival rates and impaired physical development in the second-generation offspring.

Introduction. In recent decades, wildfires have become more frequent and intense in many fire-prone areas. However, the mechanisms of smoke cytotoxicity at the cellular level are poorly understood. The study of peat smoke extract (PSE) cytotoxicity in fibroblasts is an important model for studying the acute and chronic effects of smoke exposure.Materials and methods. The cytotoxicity of peat smoke was assessed in a series of in vitro experiments using PSE in 8 dilutions (12.5, 25, 37.5, 50, 62.5, 75, 87.5 and 100%) on 3T3-SV forty mouse embryonic fibroblasts. The cytotoxic effect was assessed after 24-hour incubation by determining the concentration of lactate dehydrogenase (LDH) in the culture medium and performing the MTT test; a morphological assessment of the cells was given.Results. The results of the study indicate that PSE primarily leads to a decrease in the metabolic activity in fibroblasts, as evidenced by a lower value of the mean inhibitory concentration (IC50) (53.6%) calculated by the MTT test. When assessing the cytotoxic effect of PSE in the LDH test, a sharp decrease in cell viability was observed at its concentration above 62.5%, the IC50 value in this test was 57.7%.Limitations. The study is limited to the investigation of the cytotoxicity of PSE on the 3T3-SV 40 cell culture using morphological assessment, MTT test and determination of LDH concentration.Conclusion. As a result of the conducted studies, an assessment of the impact of peat smoke on fibroblasts in vitro was carried out, with the help of which a primary toxicological characteristic of PSE was given.Compliance with ethical standards. The study was approved by the local ethics committee of the East-Siberian Institute of Medical and Ecological Research (Protocol No.7 of 12/15/2023), conducted in accordance with the European Convention for the Protection of Vertebrate Animals Used for Experiments or for Other Scientific Purposes (ETS N 123), Directive 2010/63/EC of the European Parliament and the Council of 09/22/2010 on the protection of animals used for scientific purposes.Contribution: Abramova V.A. – concept and design of research, data collection and processing, statistical data processing, text writing, editing; Vokina V.A. – concept and design of research, data collection and processing, statistical data processing, text writing; Sosedova L.M. – concept and design of research, editing. All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.Conflict of interest. The authors declare no conflict of interest.Funding. The work was carried out according to the research plan within the framework of the state task.Received: July 20, 2025 / Revised: October 3, 2025 / Accepted: October 15, 2025 / Published: December 19, 2025

Introduction. A promising direction of nanotoxicology is the study of the effect of gadolinium nanoparticles on the body, which is possible using high-molecular compounds, for example, Siberian larch arabinogalactan, which has a stabilizing effect on nanoparticles.Materials and methods. As part of experimental studies, subacute (within 10 days) intragastric effects were carried out on outbred sexually mature male white rats (sixty four individuals) of gadolinium nanocomposite encapsulated in a natural polymer matrix of arabinogalactan at a dose of 500 µg/kg body weight and 5000 µg/kg body weight, respectively. The examination took place in 2 stages: immediately after the end of the seed (early period) and 6 months after the end of the exposure (long-term period). The work used a set of studies aimed at determining gonadotoxicity – histological examination of the tissues of the spermatogenic epithelium, morphometrically determined the general indicator of functional activity of the testes – the index of spermatogenesis.Results. Based on the conducted experimental studies, there has been established gonadotoxic effect of gadolinium nanoparticles on the reproductive system in male rats, expressed in the destruction of the germinal epithelium of the seminal tubules with a violation of the normal process of spermatogenesis with the administration of both doses of the studied nanocomposite, while in the long term the indicators do not return to normal. Also gadolinium nanoparticles have been established to be able to penetrate the hemato-testicular barrier, accumulating in testicular tissues.Limitations. The number of animals and the set of techniques is sufficient to study the effects of gadolinium nanoparticles encapsulated in the polysaccharide arabinogalactan on the structural and functional state of testicular tissue. Conclusion. With subacute exposure to gadolinium nanoparticles encapsulated in an arabinogalactan matrix, there has been established their gonadotoxic effect on the male reproductive system, expressed by structural and functional changes in testicular tissue.Compliance with ethical standards. The work was carried out in accordance with the protocol of experimental research, the principles set out in the European Convention for the Protection of Vertebrate Animals Used for Experiments or Other Scientific Purposes ETS No. 123, GOST 33215-2014 “Guidelines for the care and care of laboratory animals. Rules of equipment of premises and organization of procedures”, Recommendations for euthanasia of experimental animals: Part 1, Part 2. Permission was obtained from the Local Ethics Committee to conduct research (Protocol No. 8 dated 12/15/2023). Contribution: Novikov M.A. – concept and design of research, data processing, editing, writing text; Titov E.A. – concept and design of research, editing; Pankova A.A. – collection of material and data processing; Lisetskaya L.G. – data processing; Sosedova L.M. – concept and design of research, editing, writing text. All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.Acknowledgment. The team of authors would like to thank Yu.Y. Titova, Head of the Laboratory of functional nanomaterials of the Federal Research Center “A.E. Favorsky Irkutsk Institute of Chemistry’, the Siberian Branch of the Russian Academy of Sciences for her help in conducting research to determine the dimensional characteristics of gadolinium nanoparticles.Conflict of interest. The authors declare no conflict of interest.Funding. The study was carried out within the framework of the state assignment of the East Siberian Institute of Medical and Environmental Research.Received: September 12, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025