Статьи журнала - Saratov Medical Journal
Все статьи: 33
A novel approach to initial hearing assessment
Статья научная
Objective: justifying the possibility of using frequency-based hearing research via the web application ‘Automated System for Initial Hearing Assessment’. Materials and methods. The study was carried out at the Department of Otorhinolaryngology of the Samara State Medical University clinics in October 2019. It involved 91 patients 17 to 73 years old (average age 48±14.6 years). All study participants were divided into two age groups: Group I 17-59 years old), and Group II (over 60 years old). Patients were required to undergo two hearing assessment tests: using the Interacoustics AC-40 clinical audiometer and using our web application ‘Automated System for Initial Hearing Assessment’ (patent No. 2019664671). Results. The maximum difference in average hearing thresholds between pure-tone threshold audiometry and the web application in Group I was 3.3 dB at a frequency of 2 kHz on the right and 3.2 dB at frequencies of 2 and 4 kHz on the left; in Group II, it constituted 4.7 and 3.5 dB at 1 and 2 kHz, on the right, correspondingly, and 7.2 dB at 4 kHz on the left. The presented data were evaluated using the Cohen’s kappa coefficient, which confirmed high level of agreement between the results obtained using the clinical audiometer vs. our original web application. Conclusion. Based on the obtained results, a conclusion was made about the possibility of using the original web application for the initial hearing express assessment in general practice in conditions of limited availability of audiological care.
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Antimicrobial activity of toothpastes against early childhood caries
Статья научная
Objective: assessing antimicrobial activity of toothpastes with different ingredient composition recommended for infants and toddlers. Materials and Methods. The study object was dental plaque of children with decompensated form of caries under the age of 3 years old. Seven toothpastes with different composition designed for early childhood were studied. Identification of detected microorganisms was carried out via mass spectrometry. Antibacterial activity was determined by agar diffusion and serial dilution methods. Results. Toothpastes containing xylitol, lactic enzymes and ingredients of medicinal herbs exhibited the absence of a microbial growth inhibition zone. Fluoride toothpastes were active against all tested microorganisms, and the final fluoride inhibitory concentration was 0.00016-0.0025%, depending on the fluoride concentration in the toothpaste. Conclusion. The least pronounced antimicrobial activity was detected in complex toothpastes with lactic enzymes and ingredients of medicinal herbs, as well as in samples with xylitol. Simple toothpastes with organic and inorganic fluorine compounds demonstrated the best bactericidal effect.
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Статья научная
The objective of our study was to evaluate the cerebroprotective effect of xanthohumol (ХN) on experimental models of acute ischemic stroke in vivo and in vitro. Materials and methods. We used middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation (OGD) as in vivo and in vitro models. Our study subjects were Sprague-Dawley rats, which were randomly assigned to three groups: the control group and two MCAO groups with and without XN. The primary culture of cortical neurons was obtained from newborn rats. We employed the Bederson test and the corner test to evaluate neurological disorders. Results. The preliminary results indicated a possible cerebroprotective effect of XN in an ischemic stroke model. Conclusion. Preventive administration of XN before cerebral ischemia in an experiment can effectively reduce the volume of cerebral infarction and improve neurologic deficit 24 hours after MCAO.
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Change in brain electrical activity connectivity in migraine patients without aura
Статья научная
Objective: In this study, we consider how the structure of the brain EEG activity changes in patients with migraine, compared with virtually healthy volunteers without complaints of acute or chronic headache. Materials and Methods. The study of the connectivity of EEG activity was carried out on the basis of an objective assessment of pairwise synchronization between different recording channels, for which we used a method based on wavelet bicoherence. Results. Within the framework of the performed experimental study, we demonstrated an increased reactivity in the structure of connections in brain electrical activity of the patients experiencing a weak visual impact. Conclusion. A prospective study could determine the value of the described diagnostic procedure in support of the clinical decision on appropriate pharmacological and non-pharmacological prophylactic measures.
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Статья научная
The objective was to assess the effectiveness of the use of transcranial magnetic therapy in comprehensive non-drug recuperation of neonates with perinatal injury of the central nervous system. Materials and Methods. Our research involved 214 newborns with corrected age of 30 weeks of gestation and perinatal lesion of the central nervous system. Main group (n=79): neonates underwent standard pharmacotherapy in combination with comprehensive non-drug recuperation (which included dry immersion, music therapy and orolingual massage), and transcranial magnetic therapy. Comparison group (n=74): newborns underwent standard pharmacotherapy in combination with non-drug recuperation. Control group (n=61): infants received conventional pharmacotherapy. Results. In Main group, hyperexcitability syndrome was healed in 60% of infants, and autonomic visceral disorders were cured in 80% of children. CNS depression syndrome signs disappeared in 67% of neonates. A significant (p<0.05) decrease in the resistance index was noticed, along with reduction in elevated peripheral vascular resistance and expansion of physiological reflexes, especially of the oral automatism group. Odds ratio of normalization of oral reflexes by day 10 for Main group vs. Control group was 5.09 with 95% CI [1.8-13.8]; and for Main group vs. Comparison group, it was 3.0 with 95% CI [1.1-8.4]. Normalization of muscle tone and resistance index reduction by day 10 in Main group was observed 8 and 4 times more often, correspondingly, than in Control group. Odds ratios were 8.2 with 95% CI [1.8-16.3] and 4.05 with 95% CI [1.06-9.3], respectively. Conclusion. Non-drug recovery methods in combination with magnetic therapy generated the sedative effect; provided stimulation of respiratory movements and spontaneous motor activity; and contributed to restoring proper reflex action. Hence, they are recommended for inclusion in the perinatal CNS lesion therapy of neonates.
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Cognitive disorders in patients with chronic kidney disease in pre-dialysis period
Статья научная
Objective: to study the cognitive status of patients in the pre-dialysis period depending on the stage of chronic kidney disease (CKD) and the category of cardiovascular risk (CVR). Materials and Methods. We examined 98 patients with CKD in the pre-dialysis period (mean age 47.1±11.2 years). The patients were divided into three groups according to the criteria of CVR stratification. Group 1 consisted of 32 patients with a low or moderate CVR, and CKD stage C1 or C2; Group 2 included 34 patients with a high CVR and CKD stage C3a or C3b; Group 3 comprised 32 patients with a very high CVR and CKD stage C4. We used the SAGE test (Self-Administered Gerocognitive Examination) to evaluate cognitive functions. Results. Cognitive impairment (CI) was detected in 57% of the patients: 37.5% in Group 1, 44.1% in Group 2, and 90.5% in Group 3. Dementia was diagnosed in 19% of patients with CI. A correlation was found between the severity of CI, the degree of decrease in glomerular filtration rate, and the education level of CKD patients in the pre-dialysis period (p≤0.001). We established that the examined subjects with CKD were characterized by memory, constructive, spatial and logical thinking disorders. Conclusion. Chronic kidney disease is an independent risk factor for the development of CI. The latter progressed with both CKD stage and the patient’s CVR category, and was detected in 37.5% of patients with a low or moderate CVR, 44.1% of patients with a high CVR, and 90.5% of patients with a very high CVR.
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Статья научная
The objective of our study was to investigate the features of circulatory autonomic regulation in the patients with a coronary artery bypass graft surgery (CABG) or correction of a valvular heart disease (CVHD). Material and Methods. Our study enrolled 42 patients (including 12 women) aged 63 (57; 67), who underwent CABG; and 36 patients (including 16 women) aged 58 (47; 65), who underwent CVHD. Simultaneous 15-minute recordings of electrocardiograms and photoplethysmograms (PPG) were performed on all patients before and after the surgery. We assessed and analyzed statistical and frequency-related measures of heart rate variability (HRV) and index of synchronization (S) among low-frequency (LF) oscillations in HRV and PPG. Results. The values of most autonomic regulation indices in our study did not have statistically significant differences among the patients with CABG and CVHD at all stages of research. The exception was represented by the heart rate, which was higher before CVHD (p=0.013). Conclusion. In all patients with CABG, the values of HRV and S did not depend on the differences in their clinical statuses or performed cardiac surgical interventions.
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Comparative efficiency of various molecular genetic methods in diagnosing tuberculosis
Статья научная
Objective – to compare the efficacy of various molecular genetic methods for diagnosing tuberculosis and determining drug susceptibility to rifampicin (RIF). Materials and Methods. We conducted a retrospective study of the sputum analysis results on 1,992 patients with pulmonary tuberculosis treated at Saratov Oblast Clinical Tuberculosis (TB) Dispensary from 2014 through 2018. The following methods were used: real-time polymerase chain reaction (PCR), biological microarrays, automated Xpert® MTB/RIF technology. Statistical processing of the research results was carried out using the Bayes formula based on contingency tables (four-field table) and the χ2 test. When evaluating the significance of differences between relative values, we employed the critical significance level of 0.05. Results. In terms of etiological diagnosis of TB, higher diagnostic sensitivities of the real-time PCR and biological microarray methods (73.9% and 70.3%, correspondingly) were established, as compared with the Xpert® MTB/RIF method (34.2%) (p<0.001). The sensitivity of all methods depended on the massiveness of bacterial excretion and clinical form of TB. Conclusions: The Xpert MTB/RIF method exhibited lower diagnostic sensitivity in verifying the diagnosis of TB, whereas its operational characteristics in terms of determining RIF-resistance were sufficiently high (sensitivity at 89.7%, specificity at 89.1%, and efficacy at 89.4%), which was comparable with the characteristics of biological microarray method (93.9%, 71.8%, 82.9%; p=0.127, p<0.001, p=0.139, respectively).
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Статья научная
Objective: to identify the proportion of complications after suburethral implantation of polypropylene slings in women with stress urinary incontinence based on a seven-year experience. Material and Methods. We conducted the analysis of а seven-year experience in various implantation techniques of suburethral slings in 1260 women with stress urinary incontinence: inside-out and outside-in obturator sling fixation; suprapubic sling fixation and non-trocar mini-sling installment. Results. The highest incidence of complications was observed over the first two years after suburethral sling implantation was performed. Subsequently, the proportion of complications declined progressively to the lower limit values of 7-8% in the course of three last years. An incidence of early surgical complications among various suburethral sling implantation techniques had no statistically significant differences. However, after the suprapubic sling implantation, intraoperative and mesh-associated complications prevailed. Conclusion. Our study confirmed that suburethral sling implantation using suprapubic fixation method was associated with a higher incidence of complications and should have been performed exclusively for the target group of the patients, for whom safer surgical procedures were contraindicated.
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Статья научная
Objective: to study the effect of different pancreatic stump closure techniques and diameter of the main pancreatic duct on frequency and severity of acute postoperative pancreatitis after distal pancreatectomy. Material and Methods. Distal pancreatectomy was performed on 126 patients with neoplasms of body and/or tail of the pancreas. Patients were distributed among four groups based upon the pancreatic stump closure technique applied after distal pancreatectomy: group 1 (control) included the patients with isolated suturing of the main pancreatic duct in the pancreatic stump with its subsequent sealing by the gastrocolic omentum or hemostatic sponge; group 2 patients underwent isolated suturing of the main pancreatic duct in the pancreatic stump with its subsequent sealing with 2-octyl cyanoacrylate biological glue; group 3 patients had their pancreatic stump closure performed with endoscopic linear cutter stapler; group 4 was composed of the patients with external transduodenal transnasal drainage of enlarged (D>3 mm) main pancreatic duct in the pancreatic stump. Results. The occurrence of acute postoperative pancreatitis in the control group amounted to 45.8%, while, in groups 2, 3 and 4, the frequencies were 44.4, 9.7 and 15.0(%), correspondingly. Besides, the control group was characterized by declined occurrence of the moderately severe form of acute postoperative pancreatitis. Use of endoscopic linear cutter stapler and external transduodenal transnasal drainage of the enlarged main pancreatic duct caused lower acute postoperative pancreatitis frequency in the patients with main pancreatic duct in their pancreatic stumps below 5 mm in diameter. Conclusion. Use of proposed pancreatic stump closure techniques after distal pancreatectomy resulted in lower frequencies of occurrence and severity of acute postoperative pancreatitis.
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Статья научная
The objective was to study the dose-dependent effects of glucagon-like peptide-1 receptor agonist, liraglutide, on microcirculation in white rats under the alloxan-induced insulin deficiency. Materials and Methods. Our study was carried out on 70 white rats, divided into four groups: 20 intact control animals; 20 animals of the comparison group with alloxan-induced diabetes; 10 animals with insulin deficiency, injected with liraglutide at a dose of 0.2 mg/kg per day (treatment group No. 1); and 20 animals with insulin deficiency treated with liraglutide at a dose of 0.4 mg/kg per day (treatment group No. 2). Diabetic status, skin perfusion of the posterior limb and mechanisms of blood flow modulation were assessed in all groups of animals. Results. It was established that administering liraglutide at a dose of 0.4 mg/kg per day allowed achieving complete normalization of carbohydrate metabolism in rats with alloxan-induced insulin deficiency, thereby more effectively improving the state of microcirculation, compared with a dose of 0.2 mg/kg per day. Conclusion. The efficacy of correcting the microcirculatory disorders with liraglutide correlates with correcting the carbohydrate metabolism in rats with insulin deficiency and depends on liraglutide dose. The dose-dependent effect is achieved by the endothelial mechanism of flow modulation in microcirculation. However, the restoration of the vascular tone neurogenic component is independent of liraglutide dose.
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Статья научная
Objective: to investigate etiological role of opportunistic microflora in the pathogenesis of implant-associated inflammation in patients after primary knee replacement and antibiotic resistance of major infectious agent groups. Material and Methods. We conducted the retrospective analysis of microbiological samples from 383 patients with postoperative implant-associated inflammation after the primary total knee arthroplasty. Results. Gram-positive cocci (63.5%) are the leading agents of implant-associated inflammation. We also noted an increase in the etiological role of coagulase-positive staphylococci. Among the Gram-negative group, Enterobacteriaceae and non-fermenting bacteria were major agents. We revealed high resistance of Staphylococcus spp. to antibiotics of various groups, among which oxazolidinones and glycylcyclines were the most active. Gram-negative bacteria exhibited high resistance to cephalosporine and macrolides, whereas carbapenems and fluoroquinolones worked best. Conclusion. Gram-negative Enterobacteriaceae, non-fermenters, and Gram-positive cocci are the most significant etiological factors in the pathogenesis of implant-associated inflammation in patients after primary total knee arthroplasty.
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Статья научная
Objective: to estimate biocompatibility of matrices manufactured from polycaprolactone (PCL) and mineralized by vaterite (CaCO3) via studying local and systemic manifestations of inflammatory reaction in subcutaneous implantation tests on white rats. Material and Methods. The experiment was conducted on 40 rats divided into four groups of equal sizes: control, comparison (rats with imitation of implantation), negative control (rats with implanted non-biocompatible matrices) and experimental group, comprised of animals with implanted PCL/CaCO3-matrices. Local inflammatory manifestations were analyzed by morphological investigation of implantation area tissues. Systemic inflammatory manifestations were estimated via TNF-α and interleukin-1β (IL-1) concentrations in blood serum by ELISA. Results. The changes in cellular population content demonstrated that, on day 21 after the implantation, the PCL/CaCO3-matrice was evenly colonized by fibroblast cells and afterwards vascularized. Such matrices did not cause intense inflammatory reaction observed in negative control animals. It was accompanied by systemic manifestations, such as statistically significant increase in TNF-α and IL-1 concentrations. Conclusion. Our data confirmed the biocompatibility of PLC/CaCO3-scaffolds, thus experimentally substantiating the potential for their use in tissue engineering.
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Статья научная
The objective of our study was to reveal the morphofunctional interactions between allografts and the recipient nervous system from the experimental model of the mimetic musculature reinnervation. Materials and Methods. The experiments were conducted on Chinchilla rabbits (n=36). All animals were subjected to the facial nerve transection. No other manipulations were performed in the Control Group (n=9). In Treatment Group 1 (n=12), an autograft fragment of the masseter muscle with a neurovascular bundle was attached to the denervated buccinator. In Treatment Group 2 (n=15), allogeneic biomaterials – specifically, Regeneration Stimulator and Vasculogenesis Stimulator, were inserted between specified muscles. The animals were removed from the experiment on days 10, 30, 60 and 180. Tissue pieces from the operation zone were analyzed using transmission electron microscopy. Results. It was established that compensatory and restorative processes in the Control Group and Treatment Group 1 end with scarring of the boundary zone and contracture of mimetic muscles. In Treatment Group 2, we observed revascularization of mimetic musculature, as well as axonal ingrowth into the buccinator and restoration of neuromuscular synapses. Conclusion. Allogeneic biomaterial transplantation creates adequate conditions for the restoration of the organ vascular bed and the innervation apparatus of denervated mimetic muscles. The results of our experiments could be regarded as an example of restoring the interlevel relations in the human body following the use of allogeneic biomaterials.
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Статья научная
Objective: to conduct an experimental study on the properties of three different types of synthetic polyester matrices, to carry out their comparative assessment, and to identify the optimal carrier for the cultivation and transplantation of limbal stem cells while eliminating limbal insufficiency. Materials and methods. Transparency, mechanical properties (strength, relative elongation at break, and elastic modulus), biocompatibility with corneal cell cultures were assessed, and duration of matrix biodegradation in vivo were studied. Results. In the course of our study, the optical and mechanical properties of matrices, made of polylactide-glycolide (PLG), polylactide-caprolactone (PLC) and poly-E-caprolactone (PCL), were studied. It has been experimentally shown that limbal stem cells of humans and rabbits, as well as human corneal epithelial cells, adhered to the surface of all types of the studied matrices. During the cultivation process, they retained the typical structure of the actin cytoskeleton, along with the ability to proliferate and migrate. Differences in the interaction of different cell cultures with different types of carriers were revealed. The biodegradation time of 5 μm thick PLC matrices was about 30 days. Conclusion. Our results obtained implied the possibility of using 5 μm thick PLC matrices as a carrier for cultured limbal stem cells.
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Статья научная
Objective: to study the effect of the targeted delivery system of tannic acid (TA) in silver alginate microcapsules on the state of gum microvasculature in rats with intact periodontium vs. experimental periodontitis. Materials and Methods. The study was conducted on 90 white rats, distributed among six groups: the control group, two groups with intact periodontium and single application of gel with microcapsules loaded/not loaded with TA, experimental periodontitis group, and two groups of animals with periodontitis and repeated application of gel with microcapsules loaded/not loaded with TA. We assessed gingival perfusion and blood flow modulation mechanisms in rats via laser Doppler flowmetry. Results. Applying gel with silver microcapsules to an intact gum in rats caused 7.5% transient increase in perfusion and activation of microcirculation modulation. Loading microcapsules with TA reduced the severity of transient microcirculatory changes. Using gel with TA-loaded capsules in rats with periodontitis allowed achieving a more pronounced normalization of perfusion and mechanisms of microcirculation modulation vs. using gel containing microcapsules without active components. Conclusion. Loading alginate microcapsules with silver ions and TA yielded reduction of the irritating effect on gingival mucosa accompanied by an increase in the effectiveness of correcting microcirculatory disorders in periodontitis.
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Features of erythrocyte electrophoretic mobility in programmed hemodialysis patients
Статья научная
Objective: to analyze the electrophoretic properties of erythrocytes in patients receiving programmed hemodialysis treatment. Materials and Methods. The study included 100 patients with an established diagnosis of stage 5D chronic kidney disease, receiving programmed hemodialysis treatment. The control group included 17 healthy blood donors. The following indicators of erythrocyte electrophoretic activity were evaluated: oscillation amplitude, percentage of motile cells, ellipticity, and aggregation index. Results. Compared with the control group, we revealed significant changes in the amplitude of oscillations and the percentage of motile cells (p-0.001). No significant gender-dependent differences were observed (p-0.05). Statistically significant differences between young and senile age groups (p=0.048) were observed in the average oscillation amplitude, whereas ellipticity differed significantly in middle-aged vs. senile patients (p=0.040) and elderly vs. senile subjects (p=0.035). As for the effect of hemodialysis treatment duration, a reduction in the oscillation amplitude was observed when comparing maximum with minimum duration: less than 1 year (p=0.029) and 1 year (p=0.035). Aggregation index values were the highest in the groups with the minimum (p=0.044) and maximum (p=0.035) dialysis duration. Conclusion. In hemodialysis patients, the oscillation amplitude of erythrocytes was significantly reduced, with assumed tendency for further decrease associated with duration of hemodialysis treatment.
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Статья научная
Objective: to determine the features of intercellular interaction of platelets with neutrophils expressing adhesion molecules in psoriasis patients. Material and Methods. The study included 82 patients 20-60 years of age with a plaque psoriasis or pustular psoriasis. As a control group, 50 virtually healthy individuals 20-60 years old were examined. The study of the adhesion molecules spectrum on neutrophils was carried out on a Beckman Coulter FC-500 flow cytometer (USA) using monoclonal antibodies. The platelet-neutrophil aggregates were determined sensu the method by Yu.A. Vitkovsky et al. (2006). Results. In patients with psoriasis, compared with the control group, few intercellular contacts of neutrophils with platelets were revealed. Low values of platelet-neutrophil aggregates with 3, 4, and 5 lobes in the nucleus were observed. The formation of aggregates statistically significantly correlated with the expression of LFA-1 and PECAM-1 adhesion molecules by mature neutrophils. Conclusion. Low rates of intercellular interaction of platelets with three-, four-, and five-lobed neutrophils in psoriasis were indicative of their augmented migration from the peripheral blood to the epidermis. The adhesion molecules LFA-1 and PECAM-1 play a key role in the migration of platelet-neutrophil aggregates.
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Functional prognosis of acute ischemic stroke patients from their neuropsychological features
Статья научная
The objective was to evaluate the relationship between the patient neuropsychological condition and recovery of his/her motor activity disorder due to acute cerebrovascular accident. Materials and Methods. The study involved 103 patients with ischemic stroke in the pools of middle and anterior cerebral arteries. We carried out clinical and neurological assessments of the patient condition, and conducted neuropsychological testing via Beck Hopelessness Scale (BHS), Montreal Cognitive Assessment (MоCA), SF-36, and Visual Analog Scale (VAS). The examination was performed on three occasions: during the acute phase of cerebral circulatory disorders, after two weeks and within the range of 24-36 months. After the long-term follow-up, all patients were distributed among two groups: with a favorable outcome and with unfavorable outcome. We attempted to identify the most typical values of above-mentioned scales for each group. Results. The general physical health (GPhH) indicators based on the results of SF-36 (p=0.007), BHS (p=0.003 and 0.002), and VAS (p=0.025), collected after acute ischemic stroke, were prognostically significant. In both groups, the most important indicators for the stroke prognosis were MоCA (p=0.038), BHS (p=0.009) and SF-36 (GPH) (p=0.002), regardless of the stroke phase. Conclusion. The connection between the patient neuropsychological condition and restoring the motor functions after the stroke was revealed. The investigated questionnaires can be included in the multivariate forecast model of the stroke prognosis among other criteria for the outcome of this disease.
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Impact of bone marrow allotransplantation on functional state of mast cells in lymph nodes
Статья научная
Objective: to analyze the functional state of mast cells (MC) after bone marrow allotransplantation at the early stages of the experiment. Materials and Methods. The experiments were carried out on 40 outbred male mice, which were divided into 3 groups: Group 1 with intact animals (n=10); Group 2 with control animals injected with 0.85% sodium chloride solution (n=10); Group 3 with experimental animals (n=30) injected into their tail vein with a cell suspension from another mouse under ether anesthesia. The state of mast cells was evaluated by the method of staining with polychrome toluidine blue sensu P.G. Unna. Results. Forty minutes after the introduction of foreign bone marrow in the medulla, metachromatic MC were found near the vessels, and their proportion (60%) prevailed over orthochromatic MC (40%). MC were most often located in groups, especially near the vessels, in contact with each other. The morphometric parameters of MC were changing (diameter, 8.00-17.00 μm 6.00-12.00 μm vs in intact MC). Two hours after the experiment, in accordance with the degree of heparin sulfation, metachromatic mast cells were predominantly detected (92%), and extensively degranulated MC predominated (61%), p<0.05. The size of MC was changing (diameter: 3.00-9.00 μm; distance between cells: 29.00-53.00 μm). One-way analysis of variance established that there was a significant effect of the experiment duration on the change in the proportion of MC with metachromatic staining. Conclusion. An introduction of bone marrow transplant significantly changes the functional profile of mast cells.
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