Vol 165, No 6 (2018)

The role of GABAergic inhibition in the regulation of activity of the parafacial respiratory group was studied on narcotized mature rats. Microinjections of GABA_A agonist muscimol into the parafacial respiratory group inhibited external respiration and bioelectrical activity of the diaphragmatic muscle resulting in diminished tidal volume and decreased respiration rate accompanied by prolonged inspiration, expiration, and intervals between the inspiratory bursts in the phrenic electromyogram. In contrast, microinjections of GABA_A antagonist bicuculline into this group stimulated respiration and markedly increased its volumetric parameters. In addition, blockade of GABA_A receptors affected the expiratory phase and interburst intervals in the phrenic electromyogram, but produced no effect on respiration rate. These findings attested to contribution of GABA_A-mediated inhibition into the performance of parafacial respiratory group. The study revealed different roles of GABA_A receptors in modulation of the mechanisms of respiration rate control in mature rats and formation of inspiratory motor outputs originating from the parafacial respiratory group.

Different levels of progressive convulsive readiness variously influence the dynamics of changes in heart rate variability parameters, inotropic and lusitropic reserves of the myocardium, which reflects the dependence of cardiac function on the level of convulsive readiness. Its increase is accompanied by a shift in autonomic balance towards potentiation of sympathetic influences on the heart, as well as a decrease in not only systolic, but also diastolic function, which reduces functional capacity of the heart and can lead to decompensation and prenosological state.

Study of the brain and serum of male Wistar rats with the metabolic stress model detected changed proteomic profiles of emotiogenic structures and an increase of cathepsin B activity. Antiapoptotic effect of coenzyme Q10, added to the ration, was detected. Differences in the adaptation response of animals with passive and active behavior under conditions of metabolic stress were detected.

We studied the effect of O-((((4-hydroxy-3,5-di(1,7,7-trimethylbicyclo[2.2.1]hept-exo-2-yl) benzyl)oxy)ethyl)-O-(2-hydroxyethyl)-(1→4)-α-D-glucan (D-HES, 80 mg/kg, intravenously) and reference preparation ethylmethylhydroxypyridine succinate (EMHP-S, 50 mg/kg, intravenously) on rat survival and neurological deficit in 24 h after transient global cerebral ischemia in Wistar rats. Intravenous administration of D-HES and EMHP-S significantly increased the number of survivors by 68 and 78%, respectively, in comparison with the control group. In groups treated with D-HES and EMHP-S, the number of animals with severe neurological deficit was significantly lower and the number of animals moderate or mild neurological deficit was significantly higher than in the control group.

fMRI markers of mild depression were revealed using standard emotional test. Patients with mild depression and healthy volunteers were asked to determine gender of subjects in photographs with different emotional expressions (neutral, surprise, disgust, confusion, anger, sadness, fear, and joy). The pattern of response to different emotions was universal in both groups and included the largest clusters in the occipital region, as well as a certain volume in the parietal lobes and posterior lateral frontal cortex. In depression group, a lack of activation in the middle cingulate gyrus (bilaterally) and in the postcentral and inferior parietal gyrus (left) in response to presentation of sad faces. For other emotion, no large clusters of intergroup contrasts significant at p<0.05 with FWE correction were revealed. The response of the middle cingulate gyrus and the left inferior parietal lobe can be considered as a potential diagnostic marker of depressive disorders and as the target for neurofeedback.

We studied circadian rhythms of activity of hepatoprotectors (Antral, Carsil, and glutargin) under conditions of acute paracetamol-induced hepatitis simulated in the morning, afternoon, evening, and at night (09.00, 15.00, 21.00, and 03.00). Antral and Carsil exhibited similar chronoprofiles with the maximum hepatoprotective activity at 09.00 and 21.00, while glutargin exhibited circadian pattern opposite and its activity was maximum at 15.00 and 03.00.

An immunochip for multiple parallel detection of specific serum IgG in serological screening for syphilis is based on the use of an extended array of Treponema pallidum recombinant proteins and includes traditionally used immunodominant antigens (Tp15, Tp17, Tp47, and TmpA) and new synthetic proteins (Tp0277, Tp0319, Tp0453, Tp0684, Tp0965, and Tp1038). The use of individual antigens has demonstrated high analytical value of Tp0277 (periplasmatic C-terminal protease), Tp0319 (cytoplasmic membrane-associated lipoprotein TmpC), and external membrane-associated protein Tp0453 with transporting function, all of them improving significantly the efficiency of screening for syphilis in comparison with the traditional array of antigens. Multiparametric analysis of the results obtained on the immunochip with the use of linear discriminant analysis confirmed the efficiency of extended array of T. pallidum diagnostic antigens. Due to proposed modification, the “positive” and “negative” sera are clearly differentiated: the serological study showed 94.1% sensitivity and 100% specificity.

Implantation of ovarian tissue allografts in outbred Wistar rats and inbred August rats against the background of induction of donor-specific tolerance was accompanied by an increase in liver content of mononuclear cells expressing LMP2 immune of proteasome subunit by day 37 after transplantation in comparison with day 0. Graft rejection, on the contrary, was associated with a decrease in the number of LMP2⁺ cells in the liver of rats of both lines during this period. The difference in the content of these cells and the graft take rate were higher in Wistar rats. The number of mononuclear cells expressing LMP7 immune proteasome subunit in the liver did not change in rats of both lines by day 37 in comparison with day 0. Thus, the level of immune proteasomes with LMP2 subunit in mononuclear cells of the liver is related to fine mechanisms of regulation of immune responses and their shift toward graft take or rejection.

We studied the reactions of spinal ganglion neurons accompanying regeneration of the skin wound complicated by S. aureus sp. infection. The appearance of neuron groups with different morphofunctional changes was noted: reversible dystrophic and compensatory reactions and irreversible degenerative changes. The proportion of small B neurons was higher than the proportion of large type A neurons at all terms of the experiment. Application of plateletrich plasma to the wound after preliminary hydroimpulsive treatment considerably reduced cell destruction and stimulated regenerative effects in neurons starting from day 7 of the experiment. Application of platelet-rich plasma without hydroimpulsive treatment decelerated wound regeneration and increased the number of destructively changed neurons even in comparison with spontaneous wound healing. Close correlations between protein synthesis markers and stages of the wound process and its characteristics were revealed.

We studied the efficiency of bubbling air as a method of detoxification of the blood plasma and its mixtures with plasma substitutes from CCl4. The efficiency of detoxification depended on the characteristics of the obtained foams: foam forming ability, frequency rate, dispersion, stability of a foam skeleton, syneresis, etc. A hardware-software complex for extracorporeal blood plasma detoxification was developed and the programs for the control and regulation of this process were tested. Physical and mathematical models of toxicant excretion from the body during extracorporal blood detoxification were proposed. Verification of the mathematical model demonstrates high correspondence between the theoretical and experimental data.

In depressed patients, changes in spontaneous brain activity, in particular, the strength of functional connectivity between different regions are observed. The data on changes in the synchrony of different regions of interest in the brain can serve as markers of depressive symptoms and as the targets for the corresponding therapy. The study involved 21 patients with mild depression and 21 healthy volunteers; by the time of second fMRI scanning, 15 and 19 subjects, respectively). The subjects underwent two 4-min sessions of resting state fMRI with 2-4 months interval between the recordings; on the basis of these data, functional connectivity between regions of interest was assessed. During the first session, depressed patients demonstrated more pronounced connection between the right frontal eye field and cerebellar area III. When the sample was restricted to subjects who underwent both fMRI sessions, depressed patients demonstrated closer relations of the right parietal operculum and cerebellar vermis area VIII. During the second recording, healthy subjects showed stronger connectivity between more than 20 frontal, temporal, and subcortical regions of interest and cerebellum area II. In healthy participants, brainstem functional interactions increased from the first to the second fMRI-recording. In depressed subjects a number of cortical areas split from left intraparietal sulcus, but the left temporal cortex became more intra-connected. The results confirm the differences in functional connectivity between depressed and healthy subjects. At the same time, attention should be paid to the variability of the data obtained.

Metabolism of a novel anxiolytic GML-1 (N-benzyl-N-methyl-1-phenylpyrrolo[1,2-a]pirazin-3-carboxamide) in rat blood plasma was studied by HPLC-mass spectrometry. Three biotransformation products with the corresponding molecular ions were detected. A conclusion was made that the main pathways of GML-1 metabolism are oxidative reactions yielding hydroxylated, methylated, and demethylated metabolites.

We studied immunogenicity of two recombinant proteins FR.9 and FR.11-3 created on the basis of fragments of the primary structure of N. meningitidis IgA1 protease with different molecular weights containing different sets of T and B epitopes. The proteins actively protect animals infected with live virulent culture of meningococci, serogroups A, B, and C. Analysis of CD4⁺, CD8⁺, and CD19⁺ lymphocyte populations in mouse blood showed predominant contribution of different cell populations to the formation of immune response to different proteins. Injection of FR.11-3 protein to animals did no affect the immunoregulatory index, hence, this protein can be used for creation of immunologically safe vaccine preparation.

We studied the expression of Hif-1α, Nf-κb, and Vegf genes in the liver and serum levels of HIF-1α, erythropoietin, VEGF, TGF-β, 8-isoprostane, and corticosterone in Wistar rats with different resistance to hypoxia in 5 and 90 min after acute exposure to hypobaric hypoxia. In 5 min after hypoxic exposure, Hif-1α expression in the liver and serum levels of erythropoietin, VEGF, and TGF-β in high-resistant rats were higher than in low-resistant animals. In highresistant rats, the increment in expression of Nf-κb gene responsible for the control over the inflammatory processes was more pronounced than in low-resistant animals. In 90 min after hypoxic exposure, the serum levels of HIF-1α, erythropoietin, VEGF, and TGF-β returned to normal in high-resistant rats, while in low-resistant animals, an increase in 8-isoprostane and TGF-β concentrations was observed. The rats with different resistance to hypoxia were characterized by different changes in biomolecular parameters determining predilection to inflammatory diseases.

We performed comparative analysis of quantitative changes in the populations of bone marrow microenvironment cells in patients with chronic myeloid leukemia, multiple myeloma, and chronic lymphocytic leukemia in the debut, during response to chemotherapy, and during relapse/progression/loss of response. It was shown that in the active phase of hemoblastoses, the number of reticular cells and fibroblasts in trephine biopsy specimens was higher than in the phase of response to chemotherapy and than in the control group. In patients with relapse of multiple myeloma and loss of response in chronic myeloid leukemia, the percentage ratio of adipocytes in the bone marrow significantly (by 9-13-fold) increased. In addition, endotheliocytes appear in the active phase of all hemoblastoses in trephine biopsy specimens, while in the phase of response to chemotherapy and in the control group, these cells were absent. The revealed quantitative changes in bone marrow stromal cells can be taken into account during assessing the phase of hemoblastosis and effectiveness of chemotherapy.

We studied the effect of different concentrations of the allogeneic biotransplant on myocardial recovery. In Wistar rats, coronary artery was ligated and intramyocardial injection of 12 or 24 mg Alloplant biomaterial suspension was performed. Histological analysis was conducted on paraffin sections stained by Mallory. The index of the scar area was measured on preparations of transverse sections of the hearts. Allogeneic biomaterial produced cardioprotective and regenerative effect in the myocardium damaged by ischemia. After administration of Alloplant in a dose of 12 mg, the index of scar area decreased by 2.74 times; after doubling the Alloplant dose (24 mg), the index of scar area decreased by 26 times.

The expression of microRNA-17, microRNA-181a, and microRNA-519a in the villous tree in preeclampsia was analyzed using chromogenic in situ hybridization technique (CISH). It was found that in early-onset preeclampsia, the expression of microRNA-17 in the syncytiotrophoblast was higher (p<0.05) than in late preeclampsia, and the expression of microRNA-519a was higher (p<0.05) than in women with preterm birth at 26-31 weeks gestation. We revealed higher level of expression of microRNA-181a (p<0.05) in the cytoplasm of the syncytiotrophoblast of intermediate placental villi in the group with premature delivery in comparison with early preeclampsia. In full-term pregnancy, the expression of microRNA-181a in the vascular endothelium of placental villi was higher (p<0.02) than in women with premature deliveries. Analysis of the target genes associated with these microRNAs showed that damage to the trophoblast typical of preeclampsia, especially up to 34 weeks gestation, was accompanied by selective activation of genes participating in invasion and compensatory suppression of oncoprotective genes associated with the development of malignant neoplasms.

We performed a complex morphological analysis of atherosclerotic plaques obtained from 68 men with coronary atherosclerosis during coronary bypass surgery with endarterectomy. The expression of MMP-2 and MMP-9, collagen IV, CD31, CD34, factor VIII, and of smooth muscle cell actin was measured in the samples by morphometric and immunohistochemical methods. The expression of MMP-2 and MMP-9 as well as the intensity of neoangiogenesis estimated by the expression of CD31, CD34, and factor VIII in unstable plaques was significantly higher than in stable ones. Immunohistochemical analysis showed more intensive collagen IV expression in stable plaques. The observed differences in immunohistochemical phenotypes of stable and unstable atherosclerotic plaques reflect peculiarities of morphogenesis of atherosclerotic foci in the coronary arteries determining their further development.

We propose an original model of atypical extremely extensive liver resection applicable for studying of the mechanisms of early and late hepatic and extrahepatic postoperative complications. After median laparotomy and mobilization of the middle and left lobes of the liver, 2-4 mattress sutures were applied to each lobe paracavally and 1 mm proximal to the proposed line of resection, the lobe parenchyma was cut off, and electrocoagulation of the wound surface was performed; the removed part was equivalent to 80% of the liver weight. This model of liver resection was used to study the pathogenetic factors of circulatory insufficiency in the postoperative period.