Introduction. Modifying iron oxide nanoparticles (Fe₂O₃ NPs) with silver enables new developments in medicine. It is also known that different temperature treatments of NPs lead to the formation of different crystalline phases of iron oxide, which ultimately influences cellular processes. The presence of promising developments in the field of medicine does not exclude the need to study the biosafety of these materials for the patient's body and medical personnel.The aim of the study was to investigate the cytotoxicity of three types of Fe₂O₃ NP samples ligated with silver in cell cultures.

Materials and methods. The study was conducted on MDCK and Vero cell cultures, which were exposed to silver-ligated NPs followed by stepwise annealing: Fe₂O₃ S0 NPs — without additional heat treatment; Fe₂O₃ S200 NPs — annealed at 200°C; Fe₂O₃ S500 NPs — at 500°C. The cytotoxicity of the NPs was assessed using monolayer morphological analysis and the MTT assay.

Results. The Fe₂O₃ S0 NP sample at a concentration of 200 μg/ml exhibited the greatest morphological changes, causing significant destruction of the cell monolayer in both cell types: a score of 3 on Vero cells and a score of 4 on MDCK cells. Fe₂O₃ S200 and Fe₂O₃ S500 NPs exhibited significantly lower toxicity and produced a noticeable morphological effect only at a concentration of 400 μg/ml. The MTT assay results for both cell lines demonstrated low to moderate toxicity of the studied NPs in the concentration range up to 200 μg/ml.

Conclusion. Thus, the firing temperature during the synthesis of Fe₂O₃ nanoparticles may be a key factor in the toxicity of the material, affecting its interaction with cell cultures. The discrepancies in the results of the MTT test and cell morphology are related to the specific nature of the tests and require further scientific research with the selection of protocols and analysis methods. 

Сontribution:
Fedotova O.S. — study concept and design, editing;
Tambovtseva E.A. — data processing, writing;
Davidenko A.M. — data processing;
Zakharova Yu.A., Ulitko M.V. — editing.
All authors — approved the final version of the article and are responsible for the integrity of all its parts.

Funding source. This study was not supported by any external sources of funding.

Conflict of interest. The authors declare no apparent or potential conflicts of interest related to the publication of this article.

Received: 07.07.2025 / Accepted: 24.07.2026 / Published: 10.08.2026

Introduction. In international practice, when studying the toxicity and hazards of xenobiotics (including pesticides), the laboratory conducting such research must have data on the historical monitoring of each effect being studied.

The purpose of this study is to create a database of historical control of biochemical parameters of rat blood serum obtained during sanitary and toxicological studies of active substances of pesticides with different chemical structures.

Materials and methods. In accordance with the planned goal, a database was created on 15 biochemical indicators of blood serum from control animals (rats) used in chronic sanitary and toxicological studies of twelve samples of active substances of pesticides of various chemical structures in dynamics after 1, 3, 6 and 12 months from the beginning of the study. The data is constantly updated. The studies were conducted in the testing biological laboratory of the Federal Scientific Center for Hygiene named after F.F. Erisman according to the guidelines R1.2.3156-13.

Results. In the studied blood serum samples of the control groups of animals, an increase in biochemical parameters such as enzyme activity was detected with age: lactate dehydrogenase by 9.84%; alanine aminotransferase by 7.05%, aspartate aminotransferase by 29.12% and a decrease in alpha-amylase activity by 11.4%, obtained 12 months after the start studies (at the age of 15 months in male rats) regarding the indicators obtained after a month of research at the age of 3 months in animals. The identified changes should be taken into account when studying the active ingredients of pesticides in chronic sanitary and toxicological studies.

Research limitations. This article published a database of historical control of biochemical indicators of blood serum in male rats. Physiological indicators data in male rats in similar studies will be presented in the following publications.

Conclusion. The obtained results will be used as control data, along with the accompanying control data obtained during sanitary and toxicological studies of pesticide active substances, in order to substantiate the maximum non-effective doses for establishing permissible daily doses and hygienic standards for the studied compounds in food products and environmental objects.

Ethics approval. The research was approved by the Ethics committee of the Federal Scientific Center for Hygiene named after F.F. Erisman (minutes of the meeting No. 10 dated 17.11.2016).

Contribution: Epishina T.M. — conducting research, collecting and statistically processing the obtained material, writing the text, and compiling the list of references.

Funding source. This study was not supported by any external sources of funding.

Conflict of interest. The author declares no apparent or potential conflicts of interest related to the publication of this article.

Received: 20.05.2025 / Accepted: 15.06.2025 / Published: 10.08.2026

Introduction. Starvation has significant effects on rodents in the wild, affecting their physiology, behavior, and survival. Food scarcity can lead to decreased fertility, reduced resistance to infections, altered neurotransmitter balance in the brain, and diminished physical endurance. Intermittent fasting affects the antioxidant defense system and the content of reactive oxygen species in the brain and may underlie the mechanisms of changes in the resistance of rodents to various influences, which is of great practical importance.

The aim of this study was to determine gender differences in the effects of intermittent fasting on the antioxidant system in Wistar rats.

Materials and Methods. The study used an intermittent fasting model, in which animals in the experimental group (n = 13) were given access to food for one hour daily for 4 days, while control animals (n = 13) were kept in ad libitum conditions. After the end of the intermittent fasting period, the animals were euthanized and blood was collected, followed by measurement of the parameters of the antioxidant defense system of the blood and blood plasma.

Results. Statistical analysis revealed no changes in total plasma antioxidant activity after intermittent fasting in either male or female rats. However, a significant increase in the level of ceruloplasmin in the blood of experimental animals was observed in both male (by 32,5%; p < 0,01) and female rats (by 18,5%; p < 0,05). Blood catalase activity did not change after intermittent fasting in male and female rats. The activity of superoxide dismutase (third isoform) contained in the blood plasma of animals changed significantly only in females after intermittent fasting (a decrease of 24%; p < 0,05).

Study limitations. The study aimed to investigate the biochemical parameters of rat blood during dietary changes and is of interest to specialists in the relevant field.

Conclusion. Thus, intermittent fasting for 4 days leads to a change in the state of the antioxidant defense system in rodents, and the change in the activity of superoxide dismutase (third isoform) is gender-specific. This change in the antioxidant status of animals may underlie the decrease in resistance to various negative influences during intermittent fasting.

Ethics approval. The study was approved by the Ethics Committee of the Disinfectology Institute of the Federal Scientific Center of Hygiene named after F.F. Erisman (No. 2¹, 06.05.2025), conducted in accordance with the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (ETS N 123), the Directive of the European Parliament and the Council of the European Union.

Contribution:
Baizhumanov A.A. — collection of materials; data processing, writing the text;
Abrashitov G.N. — collection of materials; data processing;
Khirazova E.E. — editing;
Komarov V.Yu. — editing.
All co-authors — approval of the final version of the article, responsibility for the integrity of all parts of the article.

Funding source. This study was not supported by any external sources of funding.

Conflict of interest. The authors declare no apparent or potential conflicts of interest related to the publication of this article.

Received: 07.07.2025 / Accepted: 24.07.2026 / Published: 10.08.2026

Introduction. In the wild, rodents do not have constant access to food and are forced to constantly search for it. These conditions are analogous to a feeding regimen known as "intermittent fasting". Studying cardiac function and electrocardiogram parameters under conditions of limited food access will allow us to investigate the features of autonomic nervous system functioning in rats under near-natural conditions

Materials and Methods. The study used an intermittent fasting model, in which animals in the experimental group (n=7) were given access to food for one hour daily for 4 days, while control animals (n=7) were kept ad libitum. After the end of the intermittent fasting period, ECG recording was performed to calculate heart rate variability indicators for 3 minutes in order to analyze the state of the sympathetic and parasympathetic circuits of the autonomic regulation of the heart.

Results. Statistical analysis revealed a decrease in AMO and SI parameters and an increase in SD and RMSSD parameters in male Wistar rats 24 hours after the end of intermittent fasting. This simultaneous change in these parameters indicates a weakening of the sympathetic regulation of cardiac function and activation of the parasympathetic circuit.

Study limitations. The study aims to elucidate the visceral functions and behavioral responses of rodents when changing their diet and is of interest to pest control specialists.

Conclusion. intermittent fasting for 4 days with feeding during the day in rats leads to an increase in tonic parasympathetic influences on the functioning of the heart.

Ethics approval. The study was approved by the Ethics Committee of the Disinfectology Institute of “FSCH named after F.F. Erisman” of Rospotrebnadzor" (№. 2¹, 06.05.2025), conducted in accordance with the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (ETS N 123), the Directive of the European Parliament and the Council of the European Union.

Contribution:
Manchenko D.M. — collection of materials; data processing, writing the text;
Glazova N.Yu. — collection of materials; data processing;
Khirazova E.E. — editing;
Komarov V.Yu. — editing.
All co-authors — approval of the final version of the article, responsibility for the integrity of all parts of the article.

Funding source. This study was not supported by any external sources of funding.

Conflict of interest. The authors declare no apparent or potential conflicts of interest related to the publication of this article.

Received: 09.02.2026 / Accepted: 22.07.2026 / Published: 10.08.2026

Introduction. The problem of biodegradability and biodamage of building materials by rodents is a global economic problem and includes a large number of scientific and practical tasks related to ensuring the protection of raw materials, materials and other products from damage by rodents both during storage and during production, as well as during transportation and operation.

Materials and methods. Comparative studies were conducted on the impact of brown rats (Rattus norvegicus Berk., 1769) and house mice (Mus musculus L., 1758) on soundproofing and insulation materials and electrical cables in conditions of single and group housing.

Results. Differences in the effects of brown rats and house mice on insulating and soundproofing materials and electrical cables were identified. These differences lie in the way the rodents interact with these materials. House mice showed greater interest in insulating and soundproofing materials, primarily using them as nesting material, while brown rats preferred electrical cables.

Discussion. Differences in the effects of brown rats and house mice on soundproofing and insulation materials and electrical cables were identified. The study revealed significant behavioral differences between house mice and brown rats. Rats used insulation and soundproofing materials as bedding, while mice used them as nesting material. Rats caused more extensive and active damage to electrical cables than mice.

Limitations of the study. The research is aimed at a comparative analysis of the impact of rodents on insulating and soundproofing materials and electrical cables and is of interest to specialists in the field of disinfection, rodent control and other areas in which there is direct contact with rodents.

Conclusion. The search for and study of new materials that can withstand the damaging effects of rodents is an important area for ensuring the durability and safety of construction, industrial, and agricultural facilities in the face of increasing rodent pressure.

Ethics approval. The study was approved by the Ethics Committee of the Disinfectology Institute of the Federal Scientific Center of Hygiene named after F.F. Erisman (protocol No. 2¹, 06.05.2025), conducted in accordance with the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (ETS N 123), the Directive of the European Parliament and the Council of the European Union.

Contribution:
Gevorkyan I.S. — data processing, writing the text, concept and design of the study, editing, editing;
Kozlov A.A. — collection of materials;
Kurashova D.I. — collection of materials;
Sitnikova A.I. — collection of materials.
All co-authors — approval of the final version of the article, responsibility for the integrity of all parts of the article.

Funding source. This study was not supported by any external sources of funding.

Conflict of interest. The authors declare no apparent or potential conflicts of interest related to the publication of this article.

Received: 19.05.2025 / Accepted: 06.07.2025 / Published: 10.08.2026

When studying insect resistance to insecticides, it is important to use standard, susceptible laboratory cultures as a reference. Such a culture is the S-NIID housefly culture, reared in the insectary of the Institute of Disinfection for over 30 years. The S-NIID culture exhibits similar levels of insecticide sensitivity to other susceptible cultures maintained in scientific laboratories worldwide, such as SSS, WHO, Perm-S, and others. This retrospective study describes the resistance to housefly populations in Russia to active ingredients from various chemical groups. Data on housefly resistance to organochlorine and organophosphorus compounds, pyrethroids, neonicotinoids, and phenylpyrazoles applied topically are presented. A mosaic pattern of resistance development is confirmed, linked not to the geographic location of insect collection points, but to the history of insecticide use at specific sites. An increase in resistance to pyrethroids, phenylpyrazoles, and neonicotinoids, a decrease in resistance to organophosphorus compounds were observed in the European part of Russia. Resistance to acetamiprid, tolerance, and high resistance to pyrethroids and other compounds was observed in the Tyumen region. The dynamics of resistance levels reflect the intensity of application of a particular group of insecticides during a given time period.

Conclusion. Housefly populations resistant to a number of insecticides has been identified in various regions of Russia. Rotation of active ingredients based on their mechanisms of action on insects is recommended.

Study limitations. This study aims to retrospectively evaluate housefly resistance to insecticides and is of interest to specialists involved in disinfection and pest control.

Contributions:
Eremina O.Yu. — selection of literature and writing the first version of the article, approval of the final version of the article, responsibility for the integrity of all parts of the article;
Olifer V.V. — text editing, addition and approval of the final version of the article, responsibility for the integrity of all parts of the article.
All co-authors — conducted entomological and toxicological studies, wrote and edited the text, approved the final version of the article, and are responsible for the integrity of all parts of the article.

Funding source. This study was not supported by any external sources of funding.

Conflict of interest. The authors declare no apparent or potential conflicts of interest related to the publication of this article.

Received: 10.03.2026 / Accepted: 21.07.2026 / Published: 10.08.2026