No 5 (2021)

Introduction. The neurotoxic effect is considered as one of the variants of the toxicity of many xenobiotics. Neurotoxic effects develop not only in poisoning, but also when exposed to biological (for example, pathogens of infectious diseases) and physical (for example, ionizing and non-ionizing radiation) factors.

Materials and methods. The subject of the analysis was the phenomenon of neurotoxicity. The information was obtained by studying the databases Scopus, Web of Science, PubMed, RSCI.

Results. The absence of a single definition of the concept of «neurotoxicant» is noted. In addition to chemicals, other factors have neurotoxicity: biological, physical. The mechanisms of neurodegeneration under the influence of neurotoxicants with different mechanisms of action are similar and include excitotoxicity, neuroinflammation, suppression of mitochondrial function, inhibition of neurogenesis and gliogenesis, oxidative stress, increased BBB permeability and apoptosis. The presented features allow us to speak about the universality of the phenomenon of «neurotoxicity».

Conclusion. When considering the phenomenon of «neurotoxicity», certain difficulties arise. A clear idea of the etiological factors of this phenomenon is not fully formulated. A comprehensive classification of neurotoxicants has not been created. At the same time, the processes of neurodegeneration are very similar in cases of poisoning with neurotoxicants with different mechanisms of action, which proves the universality of the phenomenon of «neurotoxicity.

Introduction. Nanocomposites synthesized by the “green chemistry” method do not contain toxic chemicals (reducing agents and organic solvents) as carriers and/or stabilizing shells. One of the representatives of this group of materials are nanocomposites based on silver, which are increasingly used in medical practice, veterinary medicine, and in some other fields.

Material and methods. The nanocomposite is Ag0 nanoparticles coated with a highly methoxylated pectin shell. The concentration of Ag0 nanoparticles in the hydrosol of the pectin-Ag nanocomposite is 1.65 mmol/l, and the pectin content is 7.5 mg/ml. The size of the synthesized pectin-Ag nanocomposite is ~20–30 nm, more than 90% of the particles have a diameter of less than 20 nm, the value of the ξ-potential is 45.3 ± 0.7 mV. Toxicological studies were carried out on outbred rats. The main goal of the research was to study the toxic effects of the pectin-Ag nanocomposite in a subchronic experiment (90 days). At the end of the experiment, a complex of behavioral and clinical and laboratory parameters was determined, which made it possible to assess the biological effect of the nanocomposite on animals. The research results were statistically processed.

Results. With subchronic intragastric administration of the pectin-Ag nanocomposite to laboratory animals (rats) for 3 months at doses of 50, 500, and 5000 mg/kg, it was found that the nanocomposite exhibits a dose-dependent general toxic effect with critical target organs - the liver and spleen and the main biochemical markers of toxicity effect - aminotransferase, alkaline phosphatase and lactate dehydrogenase.

Conclusion. Experimental studies have made it possible to substantiate the threshold doses of the hydrosol of the pectin-Ag nanocomposite for the intragastric route of intake.

Introduction. The aim of the work was development of enzyme immunoassay for detecting I and II types of shiga-like toxins and assessment of it diagnostic properties. 

Materials and methods. For the research, we used hybridomas producing monoclonal antibodies to shiga-like toxins of types I and II, obtained at the branch of the Federal State Budgetary Institution “48 Central Research Institute” of the Ministry of Defense of Russian Federation (Kirov); BALB/c mice; shiga-like toxins of types I and II. Hybridoma cells were cultured in culture flasks and in the peritoneal cavity of BALB/c mice. Monoclonal antibodies were isolated from ascitic fluids by precipitation with a saturated solution of ammonium sulfate, followed by purification by ion exchange chromatography. The obtained preparations of monoclonal antibodies were used to develop enzyme immunoassay for the detection of shiga-like toxins of types I and II. Specific components of enzyme immunoassay were freeze-dried in a protective environment.

Results. As a result of research, preparative quantities of monoclonal antibodies against I and II types of shiga-like toxins were obtained and purified; selection of monoclonal antibodies for sorption on the solid phase and for the synthesis of immunoperoxidase conjugates was carried out. 

Conclusion. Experimental enzyme immunoassay allowing to identify 1 ng/ml I and II types of shiga-like toxins in «sandwich»-ELISA was developed.

Introduction. Herbal medicines are unique therapeutic agents that represent multicomponent complexes of biologically active substances. They have low toxicity, a wide spectrum of therapeutic action with a minimum of side effects and a relatively low cost. Capparis spinosa L. has been widely used in traditional medicine for the treatment of various diseases and health conditions.

Material and methods. An assessment of the toxicometric parameters of Capparis spinosa L. seed’s oil was done by a single oral and dermal exposure, the average lethal doses have been calculated for both routes, sensitivity by sex has been studied. The local irritant, skin resorptive, effect on the mucous membranes of the eyes of experimental animals was investigated. Sensitizing activity was studied according to the complex sensitization scheme. Processing of the results was carried out by the method of variation statistics. Standard errors and other indicators were calculated using the Litchfield-Wilcoxon probabilistic analysis method modified by Prozorovsky. The difference in mean values was estimated using Student’s t-test.

Results. The acute toxicity of the oil was not expressed, death of animals was not observed. Average lethal dose for a single oral exposure was above 7000 mg/kg and dermal more than 3000 mg/kg. Sensitivity by sex in an acute experiment has not been established. The oil had a mild irritating effect on the mucous membranes of the eyes. It did not show skin-irritating, resorptive-toxic and sensitizing effects. 

Conclusion. Capparis spinosa L. seed’s oil belongs to the 4^th hazard class (low hazard) according to the hygienic classification and safety requirements of substances.

20 октября 2021 г. исполнилось 95 лет со дня рождения Заслуженного деятеля науки Российской Федерации, действительного члена Нью-Йоркской Академии наук, доктора медицинских наук, профессора Бориса Александровича Кацнельсона.