Rabies immunoglobulin is one of the most commonly used antiviral serum drugs. In the Russian Federation, more than 400,000 people are at risk of contracting rabies every year. In order to improve the drug safety when using heterologous immunoglobulin, it is advisable to introduce such a quality indicator as molecular size distribution. This indicator reflects the distribution of single immunoglobulin molecules, their dimers, aggregates, and fragments in the drug. The study of the content of these fractions in the drug using high-performance liquid chromatography is determined by the requirements of the XIV edition of the State Pharmacopoeia of the Russian Federation. The aim of the present study was to establish the conditions for high-performance liquid chromatography when determining the molecular size distribution of heterologous rabies immunoglobulin. A method for determining the indicator of molecular size distribution using a BioSep-SEC-s3000 (“Phenomenex Inc.”, USA) column and a Biologic Duoflow (“BioRad”, USA) chromatographic system is proposed. Commercial and experimental samples of rabies immunoglobulin obtained from horse blood serum were used. When studying chromatographic parameters (resolution between peaks, retention time, peak symmetry, etc.), analysis conditions in accordance with the pharmacopoeial requirements were selected. The resolution values were: between the peaks of monomers and dimers — 1.42; between the peaks of aggregates and monomers – 3.9, between the peaks of monomers and fragments – at least 4.46. The experiment showed the specificity and repeatability of the technique. Additionally, a high degree of purification of the studied commercial samples of rabies immunoglobulin was shown, which is characterized by the absence of fractions of aggregates and fragments. The results obtained allow us to conclude that the proposed method can be used using a BioSep-SEC-s3000 column and a Biologic Duoflow chromatographic system to control the quality of heterologous rabies immunoglobulin in terms of molecular size distribution.

This research was aimed at developing a biotechnology for obtaining a latex brucellosis antigenic diagnosticum based on polyacrolein microspheres. This diagnosticum is intended for detecting antibodies against brucellosis in a latex agglutination reaction in human blood sera. Optimal conditions for latex sensitization with the antigen in the ratio of 1:3 at 45°C for 3 h followed by blocking of active centers with 0.5% gelatin were determined. The developed preparation showed high efficiency, which confirmed its prospects for brucellosis diagnostics. The analytical sensitivity of the diagnosticum was not less than 1:2560, in the absence of cross-reactions with heterologous sera. The diagnostic characteristics of experimental series of the preparation in control testing showed a sensitivity of 80% and a specificity of 93.33%.

Chemoresistance is a key factor restricting the use of anticancer drugs in the treatment of non-small cell lung cancer. Data on the sensitivity of tumor cells in vitro to prescribed cytostatic drugs can facilitate the prediction of cell chemoresistance for selecting optimal drugs aimed at curbing the disease and suppressing tumor growth. It is known that methods for assessing the sensitivity of cells depend on their metabolic activity. In view of this, we conducted a preliminary experiment to assess the proliferative activity of cells, which allowed us to select the concentration of cells in the exponential growth phase and calibrate the method for cell cultures.

This work investigated the effect of low-intensity electromagnetic radiation of extremely high frequency (EMR EHF) on stress-induced changes in hematological parameters in rats. The isolated action of stress factors of varying intensity was shown to significantly change a number of hematological parameters of male rats, while their combined action with EMR EHF modifies the effects of isolated stress factors. Thus, under the conditions of hypokinetic stress (HS) relative to the control, the number of erythrocytes increased by 12.7% (p<0.05); under oxidative stress (OS), hematocrit values decreased by 19.0% (p<0.001); and under acute stress, the mean concentration of hemoglobin in erythrocytes increased by 22.6% (p<0.05). The effect of stress factors of various origins in combination with EMR EHF significantly changed the effects characteristic of isolated action of these stress factors. Thus, hypokinetic stress in combination with low-intensity electromagnetic radiation of extremely high frequency (HS-EHF) compared to HS reduced the number of erythrocytes by 11.0% (p<0.05) and the hemoglobin level by 11.2% (p<0.001), restoring these indices to the control level. The combined effect of OS-EHF neutralized the effect of hematocrit reduction in OS, although reducing the mean corpuscular volume and increased the mean corpuscular hemoglobin concentration by 24.3% (p<0.001) compared to the control. The number of leukocytes and lymphocytes decreased in OS and OS-EHF, while the combination of OS with EMR EHF weakened the stress-related damaging effect of OS.

The dependence of adaptive and compensatory reactions of the kidneys on the sensitivity of β2-adrenoreceptors was studied in a rat model of unilateral ureteral obstruction. The kidney morphology was examined after 24, 48, and 72 hours of obstruction or 30 days after its termination in rats with different adrenoreactivity. In hyperreactive rats, destruction of the tubules, reduced proportion of blood vessels, and leukocyte infiltration of the interstitium were predominant. However, vacuole dystrophy of the tubular epithelium and hemostasis in the medullary vessels prevailed in hyporeactive rats. Following 30 days after 72 h of obstruction, changes in the kidneys of hyper- and hyporeactive rats were more distinct than in normoreactive ones. Thus, the response of the kidneys to ureteral obstruction depends on the β2-adrenoreceptor sensitivity. Importantly both increased and decreased adrenoreactivity deteriorates the recovery.

In this work, we conduct a comparative morphological study of the diversity of glial cells in the tissues and organs of the mediastinum of newborn rats using immunohistochemical markers. In rats aged 1 day, the innervation of the organs of the cardiovascular, digestive, and respiratory systems was studied in frontal sections through the cardiopulmonary complex (using the neural immunohistochemical protein marker PGP 9.5 and glial markers GFAP and S100β). In the mediastinal organs (SRDS), two type of glia — astrocyte-like cells and neurolemmocytes — were revealed. Astrocyte-like cells are similar to the glia of the CNS, neurolemmocytes or Schwann cells are similar to the glia of the PNS. Some were found in the neuropil of the Aurbach's ganglionic plexus of the enteric nervous system of the esophagus, and others were detected in the ganglia, microganglia, in the large trunks, and bundles of the nerve plexuses of the parasympathetic and sympathetic divisions of the somatic and autonomic nervous system. Among the neurolemmocytes in the SRDS, the following populations were identified: myelin-forming Schwann cells, neurolemmocytes of unmyelinated nerve fibers, neurolemmocytes of the Remak fascicles of the main terminal synaptic plexus, as well as satellite or capsule cells of neurocytes of the intramural ganglia. According to the modern knowledge, glia plays an important role in the functioning of vital organs in the norm, as well as in the preservation of the integrity of neural structures in pathology. Therefore, the results obtained are important for biomedical research on the development of new therapies aimed at changing the functional status of glial cells.

Irradiation of malignant neoplasms of the liver and abdominal organs can lead to the development of radiation hepatitis and liver failure. In addition, the acute inflammatory response stimulates collagenogenesis, which causes radiation-induced fibrosis. It appears promising to study the protective properties of ascorbic acid, which is a proven antioxidant capable of reducing the degree of radiation-induced liver fibrosis. In this study, we aim to assess the degree of radiation-induced liver fibrosis both in a model of chronic radiation hepatitis and against the background of administration of ascorbic acid. Wistar rats (n=40) were divided into four experimental groups: I – control (n=10); II – electron irradiation (n=10); III – administration of ascorbic acid before electron irradiation (n=10); IV – administration of ascorbic acid (n=10). Animals of all groups (I–IV) were removed from the experiment three months after the last fraction. A histological examination of liver fragments and histochemical staining according to Masson were performed. When performing histochemical staining of liver fragments according to Masson in the third month of the experiment, it was found that the area of collagen and reticular fibers stained with aniline blue practically retained control values in the group of pre-irradiation administration of ascorbic acid. For comparison, in the group of electron irradiation, a proliferation of the fibrous component was noted against the background of radiation hepatitis signs. Pre-irradiation administration of ascorbic acid slows down the development and decrease the severity of radiation-induced liver fibrosis three months after fractional local irradiation with electrons at a total dose of 30 Gy (in a model of radiation hepatitis).

The spleen is an organ of the immune system that is involved in the B-cell immune response. In certain areas of the spleen, naive and mature B lymphocytes are localized. Upon a decrease in B cells in the bloodstream, the spleen replenishes their number. In this organ, antibodies are formed, which are an important link in the humoral immune response. The conducted experiment revealed that a single administration of ethyl carbamate causes changes in both the lungs and the spleen. An analysis of histological sections showed that, six months after the receipt of ethyl carbamate, the spleen showed signs of white pulp involution, along with a decrease in the number of CD21⁺ cells. This indicates an inhibition of the B-cell immune response and a probable decrease in the humoral immune response.